Mehmet Ziya Z Firat
Akdeniz University, Department of Animal Science, Faculty Member
The aim of the study was to examine whether the TGF-beta1 T(861-20)-C gene polymorphism might be useful in identifying individuals with increased susceptibility to postmenopausal bone loss within the Turkish women population. T(861-20)-C... more
The aim of the study was to examine whether the TGF-beta1 T(861-20)-C gene polymorphism might be useful in identifying individuals with increased susceptibility to postmenopausal bone loss within the Turkish women population. T(861-20)-C polymorphism was genotyped in 616 postmenopausal women selected from the Turkish population: 311 postmenopausal osteoporotic women (OP) aged 45-65 years (mean age 58 years) and a control group (CG) of 305 postmenopausal women in the same age range (mean age 53 years) with normal bone mineral density. We have not found any significant differences in the frequency of the individual genotypes between the osteoporotic and control groups. The distribution of the T(861-20)-C genotypes was for Lumbar spine, CC, 74.0% in OP, 75.1% in CG; TC, 24.1% in OP, 23.9% in CG; TT, 1.9% in OP, 1.0% in CG; and for femoral neck, CC, 76.8% in OP, 72.8% in CG; TC, 22.1% in OP, 25.5% in CG; TT 1.1% in OP, 1.7% in CG. T(861-20)-C polymorphism was not found to be associated with bone mineral density in postmenopausal Turkish women. It was argued that this will be a pioneering study for the future research and therapies.
The aim of this study is to determine the relationship between fear of childbirth and anxiety levels of Turkish population. 49.4% of the pregnant women were nulliparous, and 50.6% were multiparous. 41.1% of them have clinical level of... more
The aim of this study is to determine the relationship between fear of childbirth and anxiety levels of Turkish population. 49.4%
of the pregnant women were nulliparous, and 50.6% were multiparous. 41.1% of them have clinical level of fear of childbirth. As
a result of correlation analysis, a significant relationship was determined between fear of childbirth and anxiety (r= 0.42, p<0.01).
According to the findings, fear of childbirth was positive and moderate correlated with anxiety. Fear of childbirth is a major
problem during pregnancy. Anxiety and fear of childbirth must be handled carefully by health care professionals.
of the pregnant women were nulliparous, and 50.6% were multiparous. 41.1% of them have clinical level of fear of childbirth. As
a result of correlation analysis, a significant relationship was determined between fear of childbirth and anxiety (r= 0.42, p<0.01).
According to the findings, fear of childbirth was positive and moderate correlated with anxiety. Fear of childbirth is a major
problem during pregnancy. Anxiety and fear of childbirth must be handled carefully by health care professionals.
Mediterranean countries have noticeable affect on the world wine exportation. Among these countries France, Greece and Turkey are selected for this study because of different wine market, trade systems and wine policies they have. In this... more
Mediterranean countries have noticeable affect on the world wine exportation. Among
these countries France, Greece and Turkey are selected for this study because of different wine
market, trade systems and wine policies they have. In this study, cointegration analysis was
conducted for real wine export prices and real exchange rates for France, Greece and Turkey. The
long term relationships between real exchange rates and real wine export values were explored by
using cointegration analysis. Annual data from 1970 to 2003 was used for this analysis and the
data sets were found to be integrated of the same order. It was also found that they move together
in the long run by Johansen Cointegration Test. Then, Error Correction Model (ECM) was applied to
search any short term relations and impacts of exchange rate variations on wine exports. French
and Greek monetary policies affect their wine export volume by the years. Therefore, any
depreciation of local currency in dollar terms will lead to increase of exports vice versa. On the
other hand, Turkish wine real export value and real exchange rate were found not cointegrated.
Since, there was not any cointegrated vector, any exchange rate volatility do not influence Turkish
real export wine value. Subsequently, the reasons of wine market failures in these countries and
pursued policies were discussed.
these countries France, Greece and Turkey are selected for this study because of different wine
market, trade systems and wine policies they have. In this study, cointegration analysis was
conducted for real wine export prices and real exchange rates for France, Greece and Turkey. The
long term relationships between real exchange rates and real wine export values were explored by
using cointegration analysis. Annual data from 1970 to 2003 was used for this analysis and the
data sets were found to be integrated of the same order. It was also found that they move together
in the long run by Johansen Cointegration Test. Then, Error Correction Model (ECM) was applied to
search any short term relations and impacts of exchange rate variations on wine exports. French
and Greek monetary policies affect their wine export volume by the years. Therefore, any
depreciation of local currency in dollar terms will lead to increase of exports vice versa. On the
other hand, Turkish wine real export value and real exchange rate were found not cointegrated.
Since, there was not any cointegrated vector, any exchange rate volatility do not influence Turkish
real export wine value. Subsequently, the reasons of wine market failures in these countries and
pursued policies were discussed.
Fitting non-linear models to the milk yield records of dairy cows is of particular importance for both breeding and management purposes as they provide a summary of the pattern of milk production with a few parameters that are... more
Fitting non-linear models to the milk yield records of dairy cows is of particular importance
for both breeding and management purposes as they provide a summary of the pattern of milk
production with a few parameters that are biologically interpretable in animal science. In this
study, hierarchical modeling of the test day milk yield data collected on monthly interval was
considered and the non-linear three parameter Wood’s incomplete gamma function was used
to obtain the lactation curves of 200 Holstein cows. Bayesian approach was utilized in
estimation of model parameters. Some characteristics of lactation such as persistency, peak
time and peak yield were also derived as well as total milk yield for each cow.
for both breeding and management purposes as they provide a summary of the pattern of milk
production with a few parameters that are biologically interpretable in animal science. In this
study, hierarchical modeling of the test day milk yield data collected on monthly interval was
considered and the non-linear three parameter Wood’s incomplete gamma function was used
to obtain the lactation curves of 200 Holstein cows. Bayesian approach was utilized in
estimation of model parameters. Some characteristics of lactation such as persistency, peak
time and peak yield were also derived as well as total milk yield for each cow.
The aim of this study was to estimate the heritability for some growth traits of Japanese quail through the estimation of variance components by Bayesian methodology. For this purpose, 340 progenies of 34 sires were used. Live weight... more
The aim of this study was to estimate the heritability for some
growth traits of Japanese quail through the estimation of variance
components by Bayesian methodology. For this purpose, 340 progenies
of 34 sires were used. Live weight (LW42) and absolute and relative
growth rates at 42 days of age (AGR42 and RGR42, respectively)
were submitted to single-trait analysis under a sire model. A software
(package MCMCglmm) was used for the estimations, and a single chain
with 65,000 rounds was run for each trait with a thinning interval of
50. Burn-in was set at 15,000 and inferences were built on posterior
samples of 1,000 draws for each trait. All marginal posterior densities
were unimodal and marginal posterior distributions of sire variance
are slightly skewed to the right. The results of the analyses showed
high, moderate, and low heritability of LW42, AGR42, and RGR42,
respectively.
growth traits of Japanese quail through the estimation of variance
components by Bayesian methodology. For this purpose, 340 progenies
of 34 sires were used. Live weight (LW42) and absolute and relative
growth rates at 42 days of age (AGR42 and RGR42, respectively)
were submitted to single-trait analysis under a sire model. A software
(package MCMCglmm) was used for the estimations, and a single chain
with 65,000 rounds was run for each trait with a thinning interval of
50. Burn-in was set at 15,000 and inferences were built on posterior
samples of 1,000 draws for each trait. All marginal posterior densities
were unimodal and marginal posterior distributions of sire variance
are slightly skewed to the right. The results of the analyses showed
high, moderate, and low heritability of LW42, AGR42, and RGR42,
respectively.
In this study, an application algorithm has been introduced to explore structural optimisation for gear pump housing. In the study, experimental and theoretical (analytical and numerical) methods are utilised. A commercial external spur... more
In this study, an application algorithm has been introduced to explore structural
optimisation for gear pump housing. In the study, experimental and theoretical
(analytical and numerical) methods are utilised. A commercial external spur
gear pump which has 17.1 Lmin−1 volumetric flow rate with maximum
pressure capacity of 250 bar has been considered for an application case study.
In the experimental section of the study, four pressure sensors (emitters)
were placed with angle intervals of 45◦, 90 ◦ , 135◦, and 180◦ on the pump’s
housing to measure operating pressure values at specific pressure regions of the
housing from inlet to outlet. According to experimental results of the pressure
measurements, a response surface analysis (RSA) was carried out and then
an estimation model (empirical equation), which could be used to calculate
pressure values at any specific region of the housing, was obtained. According
to the RSA results gained, it appears that the estimation model has 99.9% R2
value which can be used for adequately predicting accurate pressures at any
region of the housing. Subsequently, this estimation model has been adapted for
commercial finite elementmethod (FEM)-based engineering software and from
which stress distributions on the housing were simulated three dimensionally.
FEM-based simulation outputs showed that there were no failure signatures
on the pump housing. As the main conclusion of the study, it is seen that an
estimation model gives an adequate approach to predict pressure values at any
specific pressure region of the pump housing and, especially, stress distribution
results has highlighted that a structural optimisation study may be suitable for
the pump housing.
optimisation for gear pump housing. In the study, experimental and theoretical
(analytical and numerical) methods are utilised. A commercial external spur
gear pump which has 17.1 Lmin−1 volumetric flow rate with maximum
pressure capacity of 250 bar has been considered for an application case study.
In the experimental section of the study, four pressure sensors (emitters)
were placed with angle intervals of 45◦, 90 ◦ , 135◦, and 180◦ on the pump’s
housing to measure operating pressure values at specific pressure regions of the
housing from inlet to outlet. According to experimental results of the pressure
measurements, a response surface analysis (RSA) was carried out and then
an estimation model (empirical equation), which could be used to calculate
pressure values at any specific region of the housing, was obtained. According
to the RSA results gained, it appears that the estimation model has 99.9% R2
value which can be used for adequately predicting accurate pressures at any
region of the housing. Subsequently, this estimation model has been adapted for
commercial finite elementmethod (FEM)-based engineering software and from
which stress distributions on the housing were simulated three dimensionally.
FEM-based simulation outputs showed that there were no failure signatures
on the pump housing. As the main conclusion of the study, it is seen that an
estimation model gives an adequate approach to predict pressure values at any
specific pressure region of the pump housing and, especially, stress distribution
results has highlighted that a structural optimisation study may be suitable for
the pump housing.
Purpose: To translate and test the psychometric properties of the Turkish version of the Infertility Self-Efficacy Scale–Short Form (TISE-SF). Methods: The convenience sample consisted of 120 infertile women. A psychometric research... more
Purpose: To translate and test the psychometric properties of the Turkish version of the Infertility Self-Efficacy Scale–Short
Form (TISE-SF). Methods: The convenience sample consisted of 120 infertile women. A psychometric research design
was used with content and construct validity and reliability. Results: Cronbach’s alpha of .78 showed moderate reliability,
whereas item–total correlations ranged from .30 to .54. Factor analysis extracted a single component, explaining 40.3% of the
variance. Kendall W showed agreement with each expert regarding the appropriateness of the items, confirming the content
validity of the translated TISE-SF. Conclusion: The results supported the construct validity and reliability of the TISE-SF for
measuring infertility self-efficacy in a population of Turkish women. Implications: Evaluating infertile women’s perception of
self-efficacy with the TISE-SF may be useful in clinical studies in Turkey. TISE-SF can be used by professionals as a counseling
tool to help guide women in managing their treatments at infertility centers.
Form (TISE-SF). Methods: The convenience sample consisted of 120 infertile women. A psychometric research design
was used with content and construct validity and reliability. Results: Cronbach’s alpha of .78 showed moderate reliability,
whereas item–total correlations ranged from .30 to .54. Factor analysis extracted a single component, explaining 40.3% of the
variance. Kendall W showed agreement with each expert regarding the appropriateness of the items, confirming the content
validity of the translated TISE-SF. Conclusion: The results supported the construct validity and reliability of the TISE-SF for
measuring infertility self-efficacy in a population of Turkish women. Implications: Evaluating infertile women’s perception of
self-efficacy with the TISE-SF may be useful in clinical studies in Turkey. TISE-SF can be used by professionals as a counseling
tool to help guide women in managing their treatments at infertility centers.
The goal of selection studies in broilers is to obtain genetically superior chicks in terms of major economic traits, which are mainly growth rate, meat yield, and feed conversion ratio. Multiple selection schedules for growth and... more
The goal of selection studies in broilers
is to obtain genetically superior chicks in terms of
major economic traits, which are mainly growth rate,
meat yield, and feed conversion ratio. Multiple selection
schedules for growth and reproduction are used
in selection programs within commercial broiler dam
lines. Modern genetic improvement methods have not
been applied in experimental quail lines. The current
research was conducted to estimate heritabilities
and genetic correlations for growth and reproduction
traits in a Japanese quail flock. The Gompertz equation
was used to determine growth curve parameters.
The Gibbs sampling under a multi-trait animal model
was applied to estimate the heritabilities and genetic
correlations for these traits. A total of 948 quail were
used with complete pedigree information to estimate
the genetic parameters. Heritability estimates of BW,
absolute and relative growth rates at 5 wk of age (AGR
and RGR), β0 and β2 parameters, and age at point of
inflection (IPT) of Gompertz growth curve, total egg
number (EN) from the day of first lay to 24 wk of
age were moderate to high, with values ranging from
0.25 to 0.40. A low heritability (0.07) for fertility (FR)
and a strong genetic correlation (0.83) between FR and
EN were estimated in our study. Body weight exhibited
negative genetic correlation with EN, FR, RGR, and
IPT. This genetic antagonism among the mentioned
traits may be overcome using modern poultry breeding
methods such as selection using multi-trait best linear
unbiased prediction and crossbreeding.
is to obtain genetically superior chicks in terms of
major economic traits, which are mainly growth rate,
meat yield, and feed conversion ratio. Multiple selection
schedules for growth and reproduction are used
in selection programs within commercial broiler dam
lines. Modern genetic improvement methods have not
been applied in experimental quail lines. The current
research was conducted to estimate heritabilities
and genetic correlations for growth and reproduction
traits in a Japanese quail flock. The Gompertz equation
was used to determine growth curve parameters.
The Gibbs sampling under a multi-trait animal model
was applied to estimate the heritabilities and genetic
correlations for these traits. A total of 948 quail were
used with complete pedigree information to estimate
the genetic parameters. Heritability estimates of BW,
absolute and relative growth rates at 5 wk of age (AGR
and RGR), β0 and β2 parameters, and age at point of
inflection (IPT) of Gompertz growth curve, total egg
number (EN) from the day of first lay to 24 wk of
age were moderate to high, with values ranging from
0.25 to 0.40. A low heritability (0.07) for fertility (FR)
and a strong genetic correlation (0.83) between FR and
EN were estimated in our study. Body weight exhibited
negative genetic correlation with EN, FR, RGR, and
IPT. This genetic antagonism among the mentioned
traits may be overcome using modern poultry breeding
methods such as selection using multi-trait best linear
unbiased prediction and crossbreeding.
The aim of this study is to model the test day milk yields via time series methodology and to determine the number of test days which provide the most accurate forecasts. For this purpose, 10700 test day records belonging to 1070 dairy... more
The aim of this study is to model the test day milk yields via time series methodology and to determine the number of test days which provide the most accurate forecasts. For this purpose, 10700 test day records belonging to 1070 dairy cattle were used. Data were divided into two groups of 5350 records in each. One set of observations was used to model parameters, while the remaining was used for evaluating the forecast power of the model and for determining the number of test day records which provide the most accurate forecasts. ARIMA(2,0,0)(1,1,1)10 model was determined to be suitable and it was used to obtain the forecast values. The expression of the model using estimated parameter values is (1-B10)1yt = [(1-0.99129B10)/(1-0.36889B-0.06934B2)(1-0.08352B10)]at. Statistically significant and high correlations were determined between the actual and forecast values. The results indicated that the time series approach can be useful for prediction of milk yields.
The aim of this study was to examine the use of a nonlinear mixed modeling approach to growth studies of Japanese quail. Weekly BW measurements of 89 female and 89 male quail were used in the study. A well-known logistic growth function... more
The aim of this study was to examine the
use of a nonlinear mixed modeling approach to growth
studies of Japanese quail. Weekly BW measurements
of 89 female and 89 male quail were used in the study.
A well-known logistic growth function was used in the
analysis. The function was expanded to include a sex
effect and random bird effects in β0 and β2 parameters.
Analyses were performed via SAS 9.2 software. The performance
of 3 models, a fixed effects model (model 1)
including only sex effect, a mixed effects model (model
2) including sex effect in β0 and β2 parameters and random
bird effect in β0, and a mixed effects model (model
3) including sex and random bird effects in β0 and β2 parameters, was compared. The minimized value of −2
times the log-likelihood, Akaike information criterion,
corrected version of Akaike information criterion, and
Schwarz information criterion values indicated a better
fit of model 3 relative to other competitive models.
Furthermore, the error variance reduction in model 2
and model 3 compared with model 1 was 60 and 65%,
respectively, indicating the better fit of the mixed effect
models. Significant differences between sexes were
also determined in β0 and β2 parameters, in which the
males, on average, had lower β0 and higher β2 parameters
than females.
use of a nonlinear mixed modeling approach to growth
studies of Japanese quail. Weekly BW measurements
of 89 female and 89 male quail were used in the study.
A well-known logistic growth function was used in the
analysis. The function was expanded to include a sex
effect and random bird effects in β0 and β2 parameters.
Analyses were performed via SAS 9.2 software. The performance
of 3 models, a fixed effects model (model 1)
including only sex effect, a mixed effects model (model
2) including sex effect in β0 and β2 parameters and random
bird effect in β0, and a mixed effects model (model
3) including sex and random bird effects in β0 and β2 parameters, was compared. The minimized value of −2
times the log-likelihood, Akaike information criterion,
corrected version of Akaike information criterion, and
Schwarz information criterion values indicated a better
fit of model 3 relative to other competitive models.
Furthermore, the error variance reduction in model 2
and model 3 compared with model 1 was 60 and 65%,
respectively, indicating the better fit of the mixed effect
models. Significant differences between sexes were
also determined in β0 and β2 parameters, in which the
males, on average, had lower β0 and higher β2 parameters
than females.
The aim of this study was to evaluate the genetic parameters of several breast meat quality traits and their genetic relationships with some slaughter traits [BW, breast yield (BRY), and abdominal fat yield (AFY)]. In total, 1,093... more
The aim of this study was to evaluate the
genetic parameters of several breast meat quality traits
and their genetic relationships with some slaughter
traits [BW, breast yield (BRY), and abdominal fat yield
(AFY)]. In total, 1,093 pedigreed quail were slaughtered
at 35 d of age to measure BRY, AFY, and breast meat
quality traits [ultimate pH (pHU), Commission Internationale
d’Eclairage color parameters (L*, lightness;
a*, redness; and b*, yellowness), thawing and cooking
loss (TL and CL, respectively), and Warner-Bratzler
shear value (WB)]. The average pHU, L*, a*, and b*
were determined to be 5.94, 43.09, 19.24, and 7.74, respectively.
In addition, a very high WB average (7.75
kg) indicated the firmness of breast meat. High heritabilities
were estimated for BW, BRY, and AFY (0.51,
0.49, and 0.35). Genetic correlations of BW between
BRY and AFY were found to be high (0.32 and 0.58). On the other hand, the moderate negative relationship
between BRY and AFY (−0.24) implies that selection
for breast yield should not increase abdominal fat. The
pHU was found to be the most heritable trait (0.64),
whereas the other meat quality traits showed heritabilities
in the range of 0.39 to 0.48. Contrary to chickens,
the genetic correlation between pHU and L* was
low. The pHU exhibited a negative and high correlation
with BW and AFY, whereas L* showed a positive but
smaller relationship with these traits. Moreover, pHU
exhibited high negative correlations (−0.43 and −0.62)
with TL and WB, whereas L* showed a moderate relationship
(0.24) with CL. This genetic study confirmed
that the multi-trait selection could be used to improve
meat quality traits. Further, the ultimate pH of breast
meat is a relevant selection criterion due to its strong
relationships with either water-holding capacity and
texture or low abdominal fatness.
genetic parameters of several breast meat quality traits
and their genetic relationships with some slaughter
traits [BW, breast yield (BRY), and abdominal fat yield
(AFY)]. In total, 1,093 pedigreed quail were slaughtered
at 35 d of age to measure BRY, AFY, and breast meat
quality traits [ultimate pH (pHU), Commission Internationale
d’Eclairage color parameters (L*, lightness;
a*, redness; and b*, yellowness), thawing and cooking
loss (TL and CL, respectively), and Warner-Bratzler
shear value (WB)]. The average pHU, L*, a*, and b*
were determined to be 5.94, 43.09, 19.24, and 7.74, respectively.
In addition, a very high WB average (7.75
kg) indicated the firmness of breast meat. High heritabilities
were estimated for BW, BRY, and AFY (0.51,
0.49, and 0.35). Genetic correlations of BW between
BRY and AFY were found to be high (0.32 and 0.58). On the other hand, the moderate negative relationship
between BRY and AFY (−0.24) implies that selection
for breast yield should not increase abdominal fat. The
pHU was found to be the most heritable trait (0.64),
whereas the other meat quality traits showed heritabilities
in the range of 0.39 to 0.48. Contrary to chickens,
the genetic correlation between pHU and L* was
low. The pHU exhibited a negative and high correlation
with BW and AFY, whereas L* showed a positive but
smaller relationship with these traits. Moreover, pHU
exhibited high negative correlations (−0.43 and −0.62)
with TL and WB, whereas L* showed a moderate relationship
(0.24) with CL. This genetic study confirmed
that the multi-trait selection could be used to improve
meat quality traits. Further, the ultimate pH of breast
meat is a relevant selection criterion due to its strong
relationships with either water-holding capacity and
texture or low abdominal fatness.
In this study, long-term egg production was monitored in a Japanese quail flock, which had not undergone any genetic improvement, for 52 wk as of the age of sexual maturity. The study aimed to detect some traits with respect to egg... more
In this study, long-term egg production
was monitored in a Japanese quail flock, which had not
undergone any genetic improvement, for 52 wk as of the
age of sexual maturity. The study aimed to detect some
traits with respect to egg production, to determine the
cumulative hen-housed egg numbers, and to compare
goodness of fit of different nonlinear models for the
percentage of hen-day egg production. The mean age
at first egg was 38.9 d and the age at 50% egg production
was 45.3 d. The quail reached peak production at
15 wk of age (wk 9 of egg production period) when the
percentage of hen-day egg production was found to be
94%. The cumulative hen-housed egg number for 52
wk as of the age of sexual maturity was 253.08. The
monomolecular function, a nonsigmoid model, was used in the nonlinear regression analysis of the cumulative
egg numbers. Parameters a, b, and c of the monomolecular
model were estimated to be 461.70, 473.31, and
0.065, respectively. Gamma, McNally, Adams-Bell, and
modified compartmental models, widely used in hens
previously, were used in the nonlinear regression analysis
of the percentages of hen-day egg production. The
goodness of fit for these models was compared using
the values of pseudo-R2, Akaike’s information criterion,
and Bayesian information criterion. It was determined
that all the models are adequate but that the Adams-
Bell model displayed a slightly better fit for the percentage
of hen-day egg production in Japanese quail
than others.
was monitored in a Japanese quail flock, which had not
undergone any genetic improvement, for 52 wk as of the
age of sexual maturity. The study aimed to detect some
traits with respect to egg production, to determine the
cumulative hen-housed egg numbers, and to compare
goodness of fit of different nonlinear models for the
percentage of hen-day egg production. The mean age
at first egg was 38.9 d and the age at 50% egg production
was 45.3 d. The quail reached peak production at
15 wk of age (wk 9 of egg production period) when the
percentage of hen-day egg production was found to be
94%. The cumulative hen-housed egg number for 52
wk as of the age of sexual maturity was 253.08. The
monomolecular function, a nonsigmoid model, was used in the nonlinear regression analysis of the cumulative
egg numbers. Parameters a, b, and c of the monomolecular
model were estimated to be 461.70, 473.31, and
0.065, respectively. Gamma, McNally, Adams-Bell, and
modified compartmental models, widely used in hens
previously, were used in the nonlinear regression analysis
of the percentages of hen-day egg production. The
goodness of fit for these models was compared using
the values of pseudo-R2, Akaike’s information criterion,
and Bayesian information criterion. It was determined
that all the models are adequate but that the Adams-
Bell model displayed a slightly better fit for the percentage
of hen-day egg production in Japanese quail
than others.
The propose of this study is to investigate the factor structures of the W-DEQ, originally developed on UK and Swedish women, were confirmed in Turkish samples, and to obtain a new modified factor structure appropriate to Turkish culture.... more
The propose of this study is to investigate the factor
structures of the W-DEQ, originally developed on UK and Swedish
women, were confirmed in Turkish samples, and to obtain a new
modified factor structure appropriate to Turkish culture. Statistical
analyses of the data obtained were performed using SPSS© for
Windows version 13.0 and the SAS statistical software Version
9.1. Both confirmatory and exploratory factor analysis of W-DEQ
were performed in the study. Factor analysis yielded four factors
related to hope, fear, lack of positive anticipation and riskiness.
The alpha estimates of the total W-DEQ score were somewhat
higher, being 0.92 for the parous and 0.90 for the nulliparous
sample. These are well above the accepted limit of 0.70 and
indicate excellent levels of internal reliability, thus showing that
the questions were appropriate to the Turkish culture and useful
scale for the evaluation of fear of childbirth in Turkish pregnants.
structures of the W-DEQ, originally developed on UK and Swedish
women, were confirmed in Turkish samples, and to obtain a new
modified factor structure appropriate to Turkish culture. Statistical
analyses of the data obtained were performed using SPSS© for
Windows version 13.0 and the SAS statistical software Version
9.1. Both confirmatory and exploratory factor analysis of W-DEQ
were performed in the study. Factor analysis yielded four factors
related to hope, fear, lack of positive anticipation and riskiness.
The alpha estimates of the total W-DEQ score were somewhat
higher, being 0.92 for the parous and 0.90 for the nulliparous
sample. These are well above the accepted limit of 0.70 and
indicate excellent levels of internal reliability, thus showing that
the questions were appropriate to the Turkish culture and useful
scale for the evaluation of fear of childbirth in Turkish pregnants.
This methodological study was planned to translate the Wijma Delivery Expectancy/ Experience Questionnaire (W-DEQ) into Turkish and to investigate its reliability for both nulliparous and parous women in Turkish population. A total of 660... more
This methodological study was planned to translate the Wijma Delivery Expectancy/
Experience Questionnaire (W-DEQ) into Turkish and to investigate its reliability for
both nulliparous and parous women in Turkish population. A total of 660 healthy
women with normal pregnancies at gestational ages of between 28 and 40 weeks were
recruited. The internal consistency reliability (Cronbach’s a) was used for determining
the reliability of the W-DEQ. Construct validity was also determined utilizing the
known-groups method. In this study, independent sample t-tests were used to compare
the nulliparous and parous groups differing in known fear status. In order to test the
construct of the W-DEQ, Beck Anxiety Inventory, Depression Anxiety and Stress Scale
and Brief Measure of Worry Severity scales were chosen as these scales are expected to
correlate with the W-DEQ. Analysis of the construct validity of the W-DEQ version A
using Pearson’s correlation coefficients was performed for both nulliparous and parous
women separately. All the scales in both groups showed a statistically significant
correlation with the W-DEQ. The alpha coefficient (0.89) is well above the 0.70
criterion for internal consistency reliability. Turkish form of Wijma Delivery
Expectancy/Experience Questionnaire Version A was fixed as reliable and valid means
to measure the level of fear of childbirth among Turkish pregnants.
Experience Questionnaire (W-DEQ) into Turkish and to investigate its reliability for
both nulliparous and parous women in Turkish population. A total of 660 healthy
women with normal pregnancies at gestational ages of between 28 and 40 weeks were
recruited. The internal consistency reliability (Cronbach’s a) was used for determining
the reliability of the W-DEQ. Construct validity was also determined utilizing the
known-groups method. In this study, independent sample t-tests were used to compare
the nulliparous and parous groups differing in known fear status. In order to test the
construct of the W-DEQ, Beck Anxiety Inventory, Depression Anxiety and Stress Scale
and Brief Measure of Worry Severity scales were chosen as these scales are expected to
correlate with the W-DEQ. Analysis of the construct validity of the W-DEQ version A
using Pearson’s correlation coefficients was performed for both nulliparous and parous
women separately. All the scales in both groups showed a statistically significant
correlation with the W-DEQ. The alpha coefficient (0.89) is well above the 0.70
criterion for internal consistency reliability. Turkish form of Wijma Delivery
Expectancy/Experience Questionnaire Version A was fixed as reliable and valid means
to measure the level of fear of childbirth among Turkish pregnants.
The selection index is a linear weighted combination of observed measurements constructed so as to maximize genetic gain. The study is focused on the construction of optimum selection methods using analysis of variance, maximum likelihood... more
The selection index is a linear weighted combination of observed measurements constructed so as to maximize
genetic gain. The study is focused on the construction of optimum selection methods using analysis of variance, maximum likelihood
and restricted maximum likelihood methods in a balanced univariate half-sib sire model. Data sets are simulated employing the
Monte Carlo simulation method. Information on candidates themselves and their relatives are incorporated into a selection index. The
conventional theory of selection index using analysis of variance method is compared with the likelihood based ones. Both ANOVA
and likelihood based methods give similar results of selection responses due to setting the heritability estimates from ANOVA to
zero if it is negative. It is found that the predicted response is more sensitive to the heritability and phenotypic variance estimates
than the achieved response.
genetic gain. The study is focused on the construction of optimum selection methods using analysis of variance, maximum likelihood
and restricted maximum likelihood methods in a balanced univariate half-sib sire model. Data sets are simulated employing the
Monte Carlo simulation method. Information on candidates themselves and their relatives are incorporated into a selection index. The
conventional theory of selection index using analysis of variance method is compared with the likelihood based ones. Both ANOVA
and likelihood based methods give similar results of selection responses due to setting the heritability estimates from ANOVA to
zero if it is negative. It is found that the predicted response is more sensitive to the heritability and phenotypic variance estimates
than the achieved response.
Multilevel modeling is considerably useful way to analyze hierarchical data sets. The main purpose of this paper is to apply multilevel analysis in animal science and also show that this modeling technique is appropriate to analyze this... more
Multilevel modeling is considerably useful way to analyze hierarchical data sets. The main
purpose of this paper is to apply multilevel analysis in animal science and also show that
this modeling technique is appropriate to analyze this kind of data. Thus multilevel modeling
technique is used to analyze the milk yield data which has hierarchical structures,
sires nested within cows. As a result of the analysis done in this paper, it is obvious that
multilevel modeling is needed to use for analyzing this data. This illustrates that it is a convenient
way to use multilevel analysis for the data which obtained from animals when the
data have hierarchies.
purpose of this paper is to apply multilevel analysis in animal science and also show that
this modeling technique is appropriate to analyze this kind of data. Thus multilevel modeling
technique is used to analyze the milk yield data which has hierarchical structures,
sires nested within cows. As a result of the analysis done in this paper, it is obvious that
multilevel modeling is needed to use for analyzing this data. This illustrates that it is a convenient
way to use multilevel analysis for the data which obtained from animals when the
data have hierarchies.
It is believed that there is an association between the weather and rheumatic symptoms. We aimed to investigate what kind of association is present and what are the factors which determine the nature of this association. Fifty-six... more
It is believed that there is an association
between the weather and rheumatic symptoms. We aimed
to investigate what kind of association is present and what
are the factors which determine the nature of this association.
Fifty-six subjects with rheumatic disease (31 RA, 15
SpA, 10 OA) who live in Antalya were followed between
December 2005 and July 2006. Patients were asked to fill
diaries which contain questions regarding the symptoms of
their rheumatic diseases everyday. In every monthly visit,
disease activity measurement, laboratory assessment and
Beck depression inventory assessment were recorded. The
symptomatic and psychological measurements were matched
with the meteorological data of Antalya Regional
Directorate of Meteorological Service of Turkish State.
Correlation of symptoms with weather variables was
investigated. Contributory effect of weather and of psychologic
factors on symptom scores were evaluated by
stepwise multiple regression analysis. Eighty-four percent
of subjects belive in an association between weather and
rheumatism, while 57% claimed to have ability to forecast
weather. The maximum correlation coefficient between
weather and arthritis symptoms was -0.451 and the maximum
contribution of weather on symptoms was 17.1%.
Arthritis symptoms were significantly contributed by Beck
depression score. The belief about presence of weather–
arthritis association was found to be stronger than its statistical
power. Our results did not prove or rule out the
presence of weather–rheumatism association. As long as
the scientific attempts result in failure, the intuitive support
in favour of the presence of weather–arthritis association
will go on forever.
between the weather and rheumatic symptoms. We aimed
to investigate what kind of association is present and what
are the factors which determine the nature of this association.
Fifty-six subjects with rheumatic disease (31 RA, 15
SpA, 10 OA) who live in Antalya were followed between
December 2005 and July 2006. Patients were asked to fill
diaries which contain questions regarding the symptoms of
their rheumatic diseases everyday. In every monthly visit,
disease activity measurement, laboratory assessment and
Beck depression inventory assessment were recorded. The
symptomatic and psychological measurements were matched
with the meteorological data of Antalya Regional
Directorate of Meteorological Service of Turkish State.
Correlation of symptoms with weather variables was
investigated. Contributory effect of weather and of psychologic
factors on symptom scores were evaluated by
stepwise multiple regression analysis. Eighty-four percent
of subjects belive in an association between weather and
rheumatism, while 57% claimed to have ability to forecast
weather. The maximum correlation coefficient between
weather and arthritis symptoms was -0.451 and the maximum
contribution of weather on symptoms was 17.1%.
Arthritis symptoms were significantly contributed by Beck
depression score. The belief about presence of weather–
arthritis association was found to be stronger than its statistical
power. Our results did not prove or rule out the
presence of weather–rheumatism association. As long as
the scientific attempts result in failure, the intuitive support
in favour of the presence of weather–arthritis association
will go on forever.
Capsule The presence of Krueper’s Nuthatches can be predicted by variables describing topography, vegetation structure and tree species, and knowledge of these can be used to determine sites for conservation action. Aim To analyse the... more
Capsule The presence of Krueper’s Nuthatches can be predicted by variables describing topography,
vegetation structure and tree species, and knowledge of these can be used to determine sites for
conservation action.
Aim To analyse the relationships between habitat suitability, as characterized by the presence or absence
of Krueper’s Nuthatches, and different predictor variables of forest and landscape diversity by building
a logistic regression model.
Methods We investigated the influence of 11 environmental variables on the occurrence of Krueper’s
Nuthatches. Logistic regression, a particular case of GLM with binomial error distribution, was used to
identify vegetation and topographical variables that provide an explanation for the presence/absence of
Krueper’s Nuthatches in the study region of South Anatolia, Turkey.
Results Tree height, and north and southeast directions of slope were positively correlated with the
probability of occurrence of Krueper’s Nuthatches. Altitude, the presence of Red Pine and Syrian Fir trees,
the presence/absence of bushes, and southwest direction of slope were all negatively associated with the
occurrence of Krueper’s Nuthatches.
Conclusion The constructed habitat model could be used to predict locations suitable for the creation of
reservoirs for the conservation of Krueper’s Nuthatches in this region of southern Turkey.
vegetation structure and tree species, and knowledge of these can be used to determine sites for
conservation action.
Aim To analyse the relationships between habitat suitability, as characterized by the presence or absence
of Krueper’s Nuthatches, and different predictor variables of forest and landscape diversity by building
a logistic regression model.
Methods We investigated the influence of 11 environmental variables on the occurrence of Krueper’s
Nuthatches. Logistic regression, a particular case of GLM with binomial error distribution, was used to
identify vegetation and topographical variables that provide an explanation for the presence/absence of
Krueper’s Nuthatches in the study region of South Anatolia, Turkey.
Results Tree height, and north and southeast directions of slope were positively correlated with the
probability of occurrence of Krueper’s Nuthatches. Altitude, the presence of Red Pine and Syrian Fir trees,
the presence/absence of bushes, and southwest direction of slope were all negatively associated with the
occurrence of Krueper’s Nuthatches.
Conclusion The constructed habitat model could be used to predict locations suitable for the creation of
reservoirs for the conservation of Krueper’s Nuthatches in this region of southern Turkey.
Bu çalışmada yumurta verimi yönünde ıslah çalışması yapılması düşünülen bir Japon bıldırcını sürüsünde yumurta verimi ile ilgili bazı özellikler için varyans unsurları farklı yöntemlerle tahmin edilmiştir. Araştırmada bıldırcınlarda... more
Bu çalışmada yumurta verimi yönünde ıslah çalışması yapılması düşünülen bir Japon bıldırcını sürüsünde yumurta verimi ile
ilgili bazı özellikler için varyans unsurları farklı yöntemlerle tahmin edilmiştir. Araştırmada bıldırcınlarda ölçülen eşeysel olgunluk
yaşı (EOY), eşeysel olgunluk ağırlığı (EOA), yumurta ağırlığı (YA) ve kısmi yumurta verimi (YV) özellikleri kullanılmıştır. Bu özellikler
için varyans-kovaryans unsurları REML (restricted maximum likelihood), Gibbs örneklemesi, ML (maximum likelihood) ve MIVQUE
(minimum variance quadratic unbiased estimation) yöntemleri ile tahmin edilmiş ve çok özellikli genetik parametre tahminleri
gerçekleştirilmiştir. En küçük hata varyansı Gibbs örneklemesi ile tahmin edilmiş, sözü edilen yöntemin en sapmasız sonuçları
verdiği saptanmıştır. Dört yöntem ile elde edilen varyans-kovaryans matrisleri karışık model eşitliklerinde kullanılarak bıldırcınlara
ait BLUP değerleri tahmin edilmiştir. Kalıtım dereceleri, EOA özelliği için 0.28-0.38 aralığında, EOY özelliği için 0.18-0.21 aralığında,
YA özelliği için 0.36-0.43 aralığında, YV özelliği için 0.38-0.43 aralığında tahmin edilmiştir. En yüksek pozitif genetik korelasyon
dört tahmin yönteminde de EOY ile YA özellikleri arasında tahmin edilmiştir. Farklı varyans-kovaryans matrisleri kullanılarak elde
edilen BLUP değerleri arasındaki Spearman sıra korelasyon değerleri EOY için 0.90-0.99, EOA için 0.96-0.99, YA için 0.97-0.99, YV
için 0.96-0.99 aralıklarında bulunmuştur. Söz konusu özellikler için damızlık değer tahmininde Gibbs örneklemesi yönteminden
elde edilen varyans-kovaryans unsurlarının karışık model eşitliklerinde kullanılması uygun bulunmuştur.
ilgili bazı özellikler için varyans unsurları farklı yöntemlerle tahmin edilmiştir. Araştırmada bıldırcınlarda ölçülen eşeysel olgunluk
yaşı (EOY), eşeysel olgunluk ağırlığı (EOA), yumurta ağırlığı (YA) ve kısmi yumurta verimi (YV) özellikleri kullanılmıştır. Bu özellikler
için varyans-kovaryans unsurları REML (restricted maximum likelihood), Gibbs örneklemesi, ML (maximum likelihood) ve MIVQUE
(minimum variance quadratic unbiased estimation) yöntemleri ile tahmin edilmiş ve çok özellikli genetik parametre tahminleri
gerçekleştirilmiştir. En küçük hata varyansı Gibbs örneklemesi ile tahmin edilmiş, sözü edilen yöntemin en sapmasız sonuçları
verdiği saptanmıştır. Dört yöntem ile elde edilen varyans-kovaryans matrisleri karışık model eşitliklerinde kullanılarak bıldırcınlara
ait BLUP değerleri tahmin edilmiştir. Kalıtım dereceleri, EOA özelliği için 0.28-0.38 aralığında, EOY özelliği için 0.18-0.21 aralığında,
YA özelliği için 0.36-0.43 aralığında, YV özelliği için 0.38-0.43 aralığında tahmin edilmiştir. En yüksek pozitif genetik korelasyon
dört tahmin yönteminde de EOY ile YA özellikleri arasında tahmin edilmiştir. Farklı varyans-kovaryans matrisleri kullanılarak elde
edilen BLUP değerleri arasındaki Spearman sıra korelasyon değerleri EOY için 0.90-0.99, EOA için 0.96-0.99, YA için 0.97-0.99, YV
için 0.96-0.99 aralıklarında bulunmuştur. Söz konusu özellikler için damızlık değer tahmininde Gibbs örneklemesi yönteminden
elde edilen varyans-kovaryans unsurlarının karışık model eşitliklerinde kullanılması uygun bulunmuştur.
Purpose The purpose of this study was to test the reliability and validity of the Turkish version of the CQOLC in Turkey. Methods The 35-item English version of the CQOLC was translated into Turkish following the standard translation... more
Purpose The purpose of this study was to test the reliability
and validity of the Turkish version of the CQOLC in
Turkey.
Methods The 35-item English version of the CQOLC was
translated into Turkish following the standard translation
methodology. The questionnaire was administered to 237
caregivers of patients with cancer. Confirmatory and
exploratory factor analyses (CFA and EFA) were carried
out using principal component analysis with varimax
rotation and Kaiser Normalization to test its construct
validity. We used Cronbach’s alpha to examine the
CQOLC’s reliability (internal consistency).
Results The CFA did not confirm the original factor
model. The EFA yielded a 25-item measure with a fourfactor
solution with different labels for three of the four
original scales (shown in parentheses): Psychological
Distress (Burden), Disruption in Daily Life (Disruptiveness),
Caregiving Responsibility (Positive Adaptation), and
Financial Concerns (Financial Concerns). Cronbach’s
alpha for the total scale was 0.88 and subscale alpha
coefficients ranged from 0.73 to 0.83. Conclusions The results indicate some differences in the
factor structures of the CQOLC scale between Turkish and
American samples but provided preliminary support for the
Turkish version of the CQOLC as a reliable and valid
measure of the quality of life of Turkish cancer caregivers.
and validity of the Turkish version of the CQOLC in
Turkey.
Methods The 35-item English version of the CQOLC was
translated into Turkish following the standard translation
methodology. The questionnaire was administered to 237
caregivers of patients with cancer. Confirmatory and
exploratory factor analyses (CFA and EFA) were carried
out using principal component analysis with varimax
rotation and Kaiser Normalization to test its construct
validity. We used Cronbach’s alpha to examine the
CQOLC’s reliability (internal consistency).
Results The CFA did not confirm the original factor
model. The EFA yielded a 25-item measure with a fourfactor
solution with different labels for three of the four
original scales (shown in parentheses): Psychological
Distress (Burden), Disruption in Daily Life (Disruptiveness),
Caregiving Responsibility (Positive Adaptation), and
Financial Concerns (Financial Concerns). Cronbach’s
alpha for the total scale was 0.88 and subscale alpha
coefficients ranged from 0.73 to 0.83. Conclusions The results indicate some differences in the
factor structures of the CQOLC scale between Turkish and
American samples but provided preliminary support for the
Turkish version of the CQOLC as a reliable and valid
measure of the quality of life of Turkish cancer caregivers.
Objective: The aim of the present study was to evaluate the relations between T−786C and Glu298Asp polymorphisms of the endothelial nitric oxide synthase (eNOS) gene andBMDin postmenopausal Turkish women. Methods: The T−786C and Glu298Asp... more
Objective: The aim of the present study was to evaluate the relations between T−786C and Glu298Asp
polymorphisms of the endothelial nitric oxide synthase (eNOS) gene andBMDin postmenopausal Turkish
women.
Methods: The T−786C and Glu298Asp polymorphisms were genotyped by PCR-RFLP method in 311 postmenopausal
osteoporotic women (OP) and in 305 age-matched postmenopausal females (CG) with
normal BMD.
Results: None of the SNPs of the eNOS gene was significantly associated with BMD at the lumbar spine,
femoral neck, Ward’s triangle and femoral trochanter in the combined group. Mean BMD values were
therefore found to be similar across the genotypes in postmenopausal Turkish women. However, there
was a significant association between the T−786C polymorphism andBMDvalues at the lumbar spine in the
normal control group (P = 0.005), and at the femoral trochanter in the osteoporotic patients (P = 0.046). The
mean value of the lumbar spineBMDin the normal controlswas significantly higher inwomenwith the TC
genotype of the T−786C polymorphism than inwomen with the TT genotype (P = 0.0012).Women with the
CC genotype of the T−786C polymorphism in the osteoporotic patients had significantly higher BMD value
at the femoral trochanter than those with the TC (P = 0.018) and TT genotypes (P = 0.024). Frequencies
of the TC heterozygotes for T−786C polymorphism were significantly higher among osteoporotic subjects
than normal controls. Also, the CC and TT genotype frequencies of control groupwere significantly higher
than those of the osteoporotic group at the femoral neck.
Conclusions:We conclude that, although the biological role of the nitric oxide synthases iswell established,
our study does not suggest that eNOS gene polymorphisms, T−786C and Glu298Asp, aremajor contributors
to adult bone mineral density in the postmenopausal Turkish women.
polymorphisms of the endothelial nitric oxide synthase (eNOS) gene andBMDin postmenopausal Turkish
women.
Methods: The T−786C and Glu298Asp polymorphisms were genotyped by PCR-RFLP method in 311 postmenopausal
osteoporotic women (OP) and in 305 age-matched postmenopausal females (CG) with
normal BMD.
Results: None of the SNPs of the eNOS gene was significantly associated with BMD at the lumbar spine,
femoral neck, Ward’s triangle and femoral trochanter in the combined group. Mean BMD values were
therefore found to be similar across the genotypes in postmenopausal Turkish women. However, there
was a significant association between the T−786C polymorphism andBMDvalues at the lumbar spine in the
normal control group (P = 0.005), and at the femoral trochanter in the osteoporotic patients (P = 0.046). The
mean value of the lumbar spineBMDin the normal controlswas significantly higher inwomenwith the TC
genotype of the T−786C polymorphism than inwomen with the TT genotype (P = 0.0012).Women with the
CC genotype of the T−786C polymorphism in the osteoporotic patients had significantly higher BMD value
at the femoral trochanter than those with the TC (P = 0.018) and TT genotypes (P = 0.024). Frequencies
of the TC heterozygotes for T−786C polymorphism were significantly higher among osteoporotic subjects
than normal controls. Also, the CC and TT genotype frequencies of control groupwere significantly higher
than those of the osteoporotic group at the femoral neck.
Conclusions:We conclude that, although the biological role of the nitric oxide synthases iswell established,
our study does not suggest that eNOS gene polymorphisms, T−786C and Glu298Asp, aremajor contributors
to adult bone mineral density in the postmenopausal Turkish women.
1. The effect of intermittent partial surface wetting on body and surface temperature were investigated at 62 and 20 weeks of age in domestic laying hens of ATABEY (white) and ATAK (brown) strains. 2. The number of control and treatment... more
1. The effect of intermittent partial surface wetting on body and surface temperature were
investigated at 62 and 20 weeks of age in domestic laying hens of ATABEY (white) and ATAK (brown)
strains.
2. The number of control and treatment birds was 96, half of which were 62 weeks of age and the
remainder 20-week-old birds.
3. Sprinkling was done on the head, head appendages, neck and dorsal surface by releasing 10 ml/
bird in a sprinkling session. The control birds were not sprinkled at any time.
4. The first measurement was carried out immediately before sprinkling, the second just after
sprinkling, and measurements were then repeated every 5 min until the end of the 20th min.
5. Partial surface sprinkle cooling had a positive effect in relieving the birds of heat stress.
The treatment birds had lower core body, head and dorsal surface temperatures than the control birds.
6. The treatment effect on egg production was significant in young birds but not in the older ones.
investigated at 62 and 20 weeks of age in domestic laying hens of ATABEY (white) and ATAK (brown)
strains.
2. The number of control and treatment birds was 96, half of which were 62 weeks of age and the
remainder 20-week-old birds.
3. Sprinkling was done on the head, head appendages, neck and dorsal surface by releasing 10 ml/
bird in a sprinkling session. The control birds were not sprinkled at any time.
4. The first measurement was carried out immediately before sprinkling, the second just after
sprinkling, and measurements were then repeated every 5 min until the end of the 20th min.
5. Partial surface sprinkle cooling had a positive effect in relieving the birds of heat stress.
The treatment birds had lower core body, head and dorsal surface temperatures than the control birds.
6. The treatment effect on egg production was significant in young birds but not in the older ones.
Aim. This study is a report of an investigation of the psychometric properties of the Turkish version of the Menstrual Attitude Questionnaire. Background. Cultural, social and family environments influence women’s beliefs about and... more
Aim. This study is a report of an investigation of the psychometric properties of the
Turkish version of the Menstrual Attitude Questionnaire.
Background. Cultural, social and family environments influence women’s beliefs
about and attitudes towards menstruation. Awareness of these beliefs and/or attitudes
and their cultural origins is necessary to understand women and their reactions
to menstruation when offering health care. Although the Menstrual Attitude
Questionnaire has been used in several studies, the psychometric properties of the
Turkish version have not been investigated.
Methods. Confirmatory factor analyses were carried out with two different samples
– high school (n = 650) and undergraduate university students (n = 569) – in Turkey
in the spring semester of 2006. Exploratory factor analyses were then used to
modify the factor structure.
Results. Confirmatory factor analysis did not confirm the factor model reported in
the United States of America. However, compared with British and Indian samples,
Turkish attitudes showed better fit than both British and Indian samples with
comparative fit index values of 0Æ776 and 0Æ797 for the high school and university
samples respectively. Finally, exploratory factor analysis yielded a 28-item measure
for the high school sample and 31-item measure for the university sample, with a
5-factor solution. Reliability estimates of both scales were satisfactory, being 0Æ73
for the high school and 0Æ79 for the university sample.
Conclusion. The modified 5-factor Menstrual Attitude Questionnaire could be a
useful tool for assessing menstrual attitudes among Turkish high school and university
students. The overall score permits comparison with results from earlier
studies using the original instrument.
Turkish version of the Menstrual Attitude Questionnaire.
Background. Cultural, social and family environments influence women’s beliefs
about and attitudes towards menstruation. Awareness of these beliefs and/or attitudes
and their cultural origins is necessary to understand women and their reactions
to menstruation when offering health care. Although the Menstrual Attitude
Questionnaire has been used in several studies, the psychometric properties of the
Turkish version have not been investigated.
Methods. Confirmatory factor analyses were carried out with two different samples
– high school (n = 650) and undergraduate university students (n = 569) – in Turkey
in the spring semester of 2006. Exploratory factor analyses were then used to
modify the factor structure.
Results. Confirmatory factor analysis did not confirm the factor model reported in
the United States of America. However, compared with British and Indian samples,
Turkish attitudes showed better fit than both British and Indian samples with
comparative fit index values of 0Æ776 and 0Æ797 for the high school and university
samples respectively. Finally, exploratory factor analysis yielded a 28-item measure
for the high school sample and 31-item measure for the university sample, with a
5-factor solution. Reliability estimates of both scales were satisfactory, being 0Æ73
for the high school and 0Æ79 for the university sample.
Conclusion. The modified 5-factor Menstrual Attitude Questionnaire could be a
useful tool for assessing menstrual attitudes among Turkish high school and university
students. The overall score permits comparison with results from earlier
studies using the original instrument.
Objective: The ob jec ti ve of this study is to eva lu a te the va li dity and re li a bi lity of the Mens tru al At ti tu de Qu es - ti on na i re (MAQ) de ve lo ped by Bro oks-Gunn and Rub le (1980) in Tur key. Material and Met hods:... more
Objective: The ob jec ti ve of this study is to eva lu a te the va li dity and re li a bi lity of the Mens tru al At ti tu de Qu es -
ti on na i re (MAQ) de ve lo ped by Bro oks-Gunn and Rub le (1980) in Tur key. Material and Met hods: This is a met ho do lo gi cal
study. Writ ten con sent was ob ta i ned from the ow ner of the sca le, the ins ti tu ti on and oral con sent was ob ta i ned from stu dents.
The study samp le was com po sed of 534 fe ma le stu dents at Ak de niz Uni ver sity. The da ta we re col lec ted using the 33-item
MAQ. The MAQ ha ve fi ve fac tors. The fac tors and the num ber of items are: 1) mens tru a ti on as a de bi li ta ting event (12 items),
2) mens tru a ti on as a bot her so me event (6 items), 3) mens tru a ti on as a na tu ral event (5 items), 4) an ti ci pa ti on and pre dic ti on
of the on set of mens tru a ti on (5 items), and 5) de ni al of any ef fects of mens tru a ti on (7 items). The MAQ is a li kert type sca le
and has seven ra ting sca les. The in ter nal con sis tency co ef fi ci ent of the ori gi nal sca le was chan ged bet we en .95 and.97. Percen
ta ge, item to to tal sco re cor re la ti on, Cron bach alp ha co ef fi ci ent, test-re test and Va ri max Ro ta ti on Fac tor Analy sis met hods
we re used in the analy sis of the da ta. Re sults: The sca le was trans la ted in to Tur kish and re-trans la ted in to Eng lish by
spe ci a lists. For the con tent va li dity, opi ni ons of se ven ex perts we re ob ta i ned and the sco res of the ex perts fo und to be consis
tent with each ot her (W: .190, p= .084). The test-re test re li a bi lity co ef fi ci ents we re fo und to be sta tis ti cally sig ni fi cant
(p=.000). The in ter nal con sis tency re li a bi lity co ef fi ci ent was 0.79 for the to tal MAQ and va ri ed bet we en 0.44 and 0.73 for the
subs ca les. As a re sult of the item analy sis, five items cor re la ti on co ef fi ci ents we re fo und be low .20. Furt her analy sis sho wed
that exc lu ding the se items did not ha ve any sig ni fi cant ef fect on in ter nal con sis tency re li a bi lity co ef fi ci ent of MAQ’ and we -
re de ci ded to be kept in the sca le. Ac cor ding to con fir ma tory fac tor analy sis, the struc tu re of Tur kish ver si on of MAQ was
fo und in gre at re semb lan ce with the ori gi nal MAQ ex cept pla ce ment of the subs ca les. Whi le thre e items to ok part in dif fe -
rent subs ca les, two items with fac tor lo a dings ra ted be low .40 we re exc lu ded from the sca le. The item num ber of Tur kish versi
on of MAQ has go ne down to 31. Conc lu si on: In this study the MAQ was fo und to be a va lid and re li ab le to ol for me a su ring
Tur kish uni ver sity stu dents' at ti tu des abo ut mens tru a ti on. It is re com men ded that in fu tu re stu di es the MAQ be ad mi nis te -
red in gro ups with dif fe rent gen der and so ci o de mog rap hic cha rac te ris tics to test its va li dity and re li a bi lity in the se gro ups.
ti on na i re (MAQ) de ve lo ped by Bro oks-Gunn and Rub le (1980) in Tur key. Material and Met hods: This is a met ho do lo gi cal
study. Writ ten con sent was ob ta i ned from the ow ner of the sca le, the ins ti tu ti on and oral con sent was ob ta i ned from stu dents.
The study samp le was com po sed of 534 fe ma le stu dents at Ak de niz Uni ver sity. The da ta we re col lec ted using the 33-item
MAQ. The MAQ ha ve fi ve fac tors. The fac tors and the num ber of items are: 1) mens tru a ti on as a de bi li ta ting event (12 items),
2) mens tru a ti on as a bot her so me event (6 items), 3) mens tru a ti on as a na tu ral event (5 items), 4) an ti ci pa ti on and pre dic ti on
of the on set of mens tru a ti on (5 items), and 5) de ni al of any ef fects of mens tru a ti on (7 items). The MAQ is a li kert type sca le
and has seven ra ting sca les. The in ter nal con sis tency co ef fi ci ent of the ori gi nal sca le was chan ged bet we en .95 and.97. Percen
ta ge, item to to tal sco re cor re la ti on, Cron bach alp ha co ef fi ci ent, test-re test and Va ri max Ro ta ti on Fac tor Analy sis met hods
we re used in the analy sis of the da ta. Re sults: The sca le was trans la ted in to Tur kish and re-trans la ted in to Eng lish by
spe ci a lists. For the con tent va li dity, opi ni ons of se ven ex perts we re ob ta i ned and the sco res of the ex perts fo und to be consis
tent with each ot her (W: .190, p= .084). The test-re test re li a bi lity co ef fi ci ents we re fo und to be sta tis ti cally sig ni fi cant
(p=.000). The in ter nal con sis tency re li a bi lity co ef fi ci ent was 0.79 for the to tal MAQ and va ri ed bet we en 0.44 and 0.73 for the
subs ca les. As a re sult of the item analy sis, five items cor re la ti on co ef fi ci ents we re fo und be low .20. Furt her analy sis sho wed
that exc lu ding the se items did not ha ve any sig ni fi cant ef fect on in ter nal con sis tency re li a bi lity co ef fi ci ent of MAQ’ and we -
re de ci ded to be kept in the sca le. Ac cor ding to con fir ma tory fac tor analy sis, the struc tu re of Tur kish ver si on of MAQ was
fo und in gre at re semb lan ce with the ori gi nal MAQ ex cept pla ce ment of the subs ca les. Whi le thre e items to ok part in dif fe -
rent subs ca les, two items with fac tor lo a dings ra ted be low .40 we re exc lu ded from the sca le. The item num ber of Tur kish versi
on of MAQ has go ne down to 31. Conc lu si on: In this study the MAQ was fo und to be a va lid and re li ab le to ol for me a su ring
Tur kish uni ver sity stu dents' at ti tu des abo ut mens tru a ti on. It is re com men ded that in fu tu re stu di es the MAQ be ad mi nis te -
red in gro ups with dif fe rent gen der and so ci o de mog rap hic cha rac te ris tics to test its va li dity and re li a bi lity in the se gro ups.
This study investigated the efficacy of surface wetting at different thermal conditions on core body, head, and dorsal surface temperatures in laying hens. Hens were sprinkled on the head and dorsal surface by releasing a sprinkling... more
This study investigated the efficacy of
surface wetting at different thermal conditions on core
body, head, and dorsal surface temperatures in laying
hens. Hens were sprinkled on the head and dorsal surface
by releasing a sprinkling dosage of 10 mL·bird−1.
The first measurement was taken presprinkling, and the
second was taken immediately postsprinkling and then
repeated every 5 min for 20 min. The cooling water
needs for intermittent partial surface wetting to relieve
acute heat stress in the laying hens were quantified for
48 domestic laying hens under 4 experimental thermal
conditions. The hens were kept at 4 thermal conditions
at average dry-bulb temperatures of 31.30 ± 0.03, 33.20
± 0.08, 36.01 ± 0.12, and 40.24 ± 0.08°C; RH of 67.68
± 0.37, 51.78 ± 1.98, 24.59 ± 0.90, and 16.12 ± 1.55%;
and air velocities of 0.09 ± 0.00, 0.07 ± 0.00, 0.08 ± 0.00, and 0.09 ± 0.00 m·s−1, respectively. The differences
in core body, head, and dorsal surface temperatures
among the 4 thermal groups were 0.15, 0.18, 0.23,
and 0.22°C for core body temperature; 1.63, 1.44, 2.51,
and 0.97°C for core head temperature; and 1.23, 1.37,
1.41, and 0.64°C for core dorsal temperature at thermal
conditions 1, 2, 3, and 4, respectively. There were
significant differences in core body, head, and dorsal
surface temperatures among the 4 thermal condition
groups. It was concluded that the spraying interval was
directly proportional to the product of the vapor pressure
deficit and the thermal resistance of convective
mass transfer of the wetted hens, because there were
no significant differences in the air velocity among the
4 thermal condition groups and the air velocity was
very low.
surface wetting at different thermal conditions on core
body, head, and dorsal surface temperatures in laying
hens. Hens were sprinkled on the head and dorsal surface
by releasing a sprinkling dosage of 10 mL·bird−1.
The first measurement was taken presprinkling, and the
second was taken immediately postsprinkling and then
repeated every 5 min for 20 min. The cooling water
needs for intermittent partial surface wetting to relieve
acute heat stress in the laying hens were quantified for
48 domestic laying hens under 4 experimental thermal
conditions. The hens were kept at 4 thermal conditions
at average dry-bulb temperatures of 31.30 ± 0.03, 33.20
± 0.08, 36.01 ± 0.12, and 40.24 ± 0.08°C; RH of 67.68
± 0.37, 51.78 ± 1.98, 24.59 ± 0.90, and 16.12 ± 1.55%;
and air velocities of 0.09 ± 0.00, 0.07 ± 0.00, 0.08 ± 0.00, and 0.09 ± 0.00 m·s−1, respectively. The differences
in core body, head, and dorsal surface temperatures
among the 4 thermal groups were 0.15, 0.18, 0.23,
and 0.22°C for core body temperature; 1.63, 1.44, 2.51,
and 0.97°C for core head temperature; and 1.23, 1.37,
1.41, and 0.64°C for core dorsal temperature at thermal
conditions 1, 2, 3, and 4, respectively. There were
significant differences in core body, head, and dorsal
surface temperatures among the 4 thermal condition
groups. It was concluded that the spraying interval was
directly proportional to the product of the vapor pressure
deficit and the thermal resistance of convective
mass transfer of the wetted hens, because there were
no significant differences in the air velocity among the
4 thermal condition groups and the air velocity was
very low.
A linkage disequilibrium-based method for fine mapping quantitative trait loci (QTL) has been described that uses similarity between individuals’ marker haplotypes to determine if QTL alleles are identical by descent (IBD) to model... more
A linkage disequilibrium-based method for fine mapping quantitative trait loci (QTL) has been described
that uses similarity between individuals’ marker haplotypes to determine if QTL alleles are identical by
descent (IBD) to model covariances among individuals’ QTL alleles for a mixed linear model. Mapping
accuracy with this method was found to be sensitive to the number of linked markers that was included in the
haplotype when fitting the model at a putative position of the QTL. The objective of this study was to
determine the optimal haplotype structure for this IBD-based method for fine mapping a QTL in a
previously identified QTL region. Haplotypes consisting of 1, 2, 4, 6, or all 10 available markers were fit as a
‘‘sliding window’’ across the QTL region under ideal and nonideal simulated population conditions. It was
found that using haplotypes of 4 or 6 markers as a sliding ‘‘window’’ resulted in the greatest mapping accuracy
under nearly all conditions, although the true IBD state at a putative QTL position was most accurately
predicted by IBD probabilities obtained using all markers. Using 4 or 6 markers resulted in greater
discrimination of IBD probabilities between positions while maintaining sufficient accuracy of IBD
probabilities to detect the QTL. Fitting IBD probabilities on the basis of a single marker resulted in the worst
mapping accuracy under all conditions because it resulted in poor accuracy of IBD probabilities. In conclusion,
for fine mapping using IBD methods, marker information must be used in a manner that results in
sensitivity of IBD probabilities to the putative position of the QTL while maintaining sufficient accuracy of
IBD probabilities to detect the QTL. Contrary to expectation, use of haplotypes of 4–6markers to derive IBD
probabilities, rather than all available markers, best fits these criteria. Thus for populations similar to those
simulated here, optimal mapping accuracy for this IBD-based fine-mapping method is obtained with a
haplotype structure including a subset of all available markers.
that uses similarity between individuals’ marker haplotypes to determine if QTL alleles are identical by
descent (IBD) to model covariances among individuals’ QTL alleles for a mixed linear model. Mapping
accuracy with this method was found to be sensitive to the number of linked markers that was included in the
haplotype when fitting the model at a putative position of the QTL. The objective of this study was to
determine the optimal haplotype structure for this IBD-based method for fine mapping a QTL in a
previously identified QTL region. Haplotypes consisting of 1, 2, 4, 6, or all 10 available markers were fit as a
‘‘sliding window’’ across the QTL region under ideal and nonideal simulated population conditions. It was
found that using haplotypes of 4 or 6 markers as a sliding ‘‘window’’ resulted in the greatest mapping accuracy
under nearly all conditions, although the true IBD state at a putative QTL position was most accurately
predicted by IBD probabilities obtained using all markers. Using 4 or 6 markers resulted in greater
discrimination of IBD probabilities between positions while maintaining sufficient accuracy of IBD
probabilities to detect the QTL. Fitting IBD probabilities on the basis of a single marker resulted in the worst
mapping accuracy under all conditions because it resulted in poor accuracy of IBD probabilities. In conclusion,
for fine mapping using IBD methods, marker information must be used in a manner that results in
sensitivity of IBD probabilities to the putative position of the QTL while maintaining sufficient accuracy of
IBD probabilities to detect the QTL. Contrary to expectation, use of haplotypes of 4–6markers to derive IBD
probabilities, rather than all available markers, best fits these criteria. Thus for populations similar to those
simulated here, optimal mapping accuracy for this IBD-based fine-mapping method is obtained with a
haplotype structure including a subset of all available markers.
In this research, it was aimed to determine estimation of heritabilities for liveweights and liveweight gains by different methods in Japanese Quail. In the study, the 90 sires, 293 dams and 1788 offsprings were used. Estimated... more
In this research, it was aimed to determine estimation of heritabilities for liveweights and liveweight gains by
different methods in Japanese Quail. In the study, the 90 sires, 293 dams and 1788 offsprings were used. Estimated
heritabilites were found to be high and moderate level with ANOVA, ML and REML methods. The estimated
heritabilites of three methods were similar.
different methods in Japanese Quail. In the study, the 90 sires, 293 dams and 1788 offsprings were used. Estimated
heritabilites were found to be high and moderate level with ANOVA, ML and REML methods. The estimated
heritabilites of three methods were similar.
A new approach was developed to fine map a biallelic QTL using linkage disequilibrium (LD). It uses the probability that a maternal (paternal) QTL allele of each individual is the mutant QTL allele, conditional on the pedigree and marker... more
A new approach was developed to fine map a biallelic QTL using linkage
disequilibrium (LD). It uses the probability that a maternal (paternal)
QTL allele of each individual is the mutant QTL allele, conditional on
the pedigree and marker information. These probabilities were derived
recursively from the haplotype-specific mutant QTL allele frequencies
in the founders. As the haplotypes of founders are not known, their probabilities were estimated by MCMC methods. This model has fewer
parameters than the usual model, because it relates the means and covariances
of the QTL gametic values to the QTL allele effect and their
frequencies. Consequently, this approach is expected to be more acccurate.
To overcome the computing difficulties in exact calculation of
IBD probabilities, an MCMC method was used to derive approximate
conditional probabilities of inheriting maternal and paternal QTL alleles.
A residual maximum likelihood method (REML) was implemented
to map the QTL, using a Newton-Raphson algorithm. The QTL position,
QTL effect, haplotype-specific mutant QTL allele frequencies and
polygenic and residual variance components were jointly estimated for
each interval. The derivatives of the residual likelihood were obtained
by automated differentiation. A simulated population was analyzed to
compare the ability of this technique to fine map a QTL with two others
methods. In the first method, identity by descent QTL covariances
are used to model LD and cosegregation of the alleles at linked loci.
In the second, identity by descent QTL covariances are used only to
model the cosegregation of the alleles, and LD is modeled by including
the marker haplotypes as fixed effects in the model. LD was simulated
by introducing a mutation at the QTL followed by 100 generations of
random mating. Different genetic designs were simulated, under linkage
and linkage disequilibrium and with various QTL effects, to obtain
power and accuracy of the parameter estimates.
disequilibrium (LD). It uses the probability that a maternal (paternal)
QTL allele of each individual is the mutant QTL allele, conditional on
the pedigree and marker information. These probabilities were derived
recursively from the haplotype-specific mutant QTL allele frequencies
in the founders. As the haplotypes of founders are not known, their probabilities were estimated by MCMC methods. This model has fewer
parameters than the usual model, because it relates the means and covariances
of the QTL gametic values to the QTL allele effect and their
frequencies. Consequently, this approach is expected to be more acccurate.
To overcome the computing difficulties in exact calculation of
IBD probabilities, an MCMC method was used to derive approximate
conditional probabilities of inheriting maternal and paternal QTL alleles.
A residual maximum likelihood method (REML) was implemented
to map the QTL, using a Newton-Raphson algorithm. The QTL position,
QTL effect, haplotype-specific mutant QTL allele frequencies and
polygenic and residual variance components were jointly estimated for
each interval. The derivatives of the residual likelihood were obtained
by automated differentiation. A simulated population was analyzed to
compare the ability of this technique to fine map a QTL with two others
methods. In the first method, identity by descent QTL covariances
are used to model LD and cosegregation of the alleles at linked loci.
In the second, identity by descent QTL covariances are used only to
model the cosegregation of the alleles, and LD is modeled by including
the marker haplotypes as fixed effects in the model. LD was simulated
by introducing a mutation at the QTL followed by 100 generations of
random mating. Different genetic designs were simulated, under linkage
and linkage disequilibrium and with various QTL effects, to obtain
power and accuracy of the parameter estimates.
The present study was conducted to investigate the effects of probiotics on the live weight, live weight gain, feed consumption, feed efficiency and health condition of calves. Nineteen Holstein calves, divided into 2 similiar groups in... more
The present study was conducted to investigate the effects of probiotics on the live weight, live weight gain, feed
consumption, feed efficiency and health condition of calves. Nineteen Holstein calves, divided into 2 similiar groups in terms of age,
sex and live weight, were used in the trial. The first group of calves were given a probiotic at 20 g/day during the first 2 weeks
and 40 g/day in the following weeks, via milk during the first 3 months and later on via drinking water. The other group received
no probiotic. Both groups were started in the second week on the same concentrate and good quality alfalfa hay ad libitum, in
addition to milk. The probiotic used was a commercial preparation containing Saccharomyces cerevisiae, Lactobacillus acidophilus,
Bifidobacterium bifidum, Streptococcus termophilus and Aspergillus niger. Live weight at the end of the experiment, average daily
live weight gain, average daily concentrate and (concentrate + hay) intake, feed efficiency ratio calculated as (concentrate + hay) /
live weight gain for the no probiotic and probiotic groups were 145.80 ± 2.28 and 152.00 ± 3.97 kg, 631.6 ± 14.7 and 681.6
± 15.5 g; 1.727 ± 0.05 and 1.705 ± 0.06 kg; 2.403 ± 0.067 and 2.309 ± 0.071 kg; 3.80 ± 0.07 and 3.38 ± 0.08, respectively.
No significant differences were observed between the groups, except for the daily live weight gain (P < 0.05) and feed efficiency
ratio (P < 0.01). Diarrhea was observed in the control group, while there were no health problems in the probiotic group.
consumption, feed efficiency and health condition of calves. Nineteen Holstein calves, divided into 2 similiar groups in terms of age,
sex and live weight, were used in the trial. The first group of calves were given a probiotic at 20 g/day during the first 2 weeks
and 40 g/day in the following weeks, via milk during the first 3 months and later on via drinking water. The other group received
no probiotic. Both groups were started in the second week on the same concentrate and good quality alfalfa hay ad libitum, in
addition to milk. The probiotic used was a commercial preparation containing Saccharomyces cerevisiae, Lactobacillus acidophilus,
Bifidobacterium bifidum, Streptococcus termophilus and Aspergillus niger. Live weight at the end of the experiment, average daily
live weight gain, average daily concentrate and (concentrate + hay) intake, feed efficiency ratio calculated as (concentrate + hay) /
live weight gain for the no probiotic and probiotic groups were 145.80 ± 2.28 and 152.00 ± 3.97 kg, 631.6 ± 14.7 and 681.6
± 15.5 g; 1.727 ± 0.05 and 1.705 ± 0.06 kg; 2.403 ± 0.067 and 2.309 ± 0.071 kg; 3.80 ± 0.07 and 3.38 ± 0.08, respectively.
No significant differences were observed between the groups, except for the daily live weight gain (P < 0.05) and feed efficiency
ratio (P < 0.01). Diarrhea was observed in the control group, while there were no health problems in the probiotic group.
In this research, it was aimed to determine the variance components of live weights by different methods in New Zeland White Rabbits. In the study, 16 sires, 68 dams and offsprings obtained from these sires and dams were used in the first... more
In this research, it was aimed to determine the variance components of live weights by different methods in New Zeland White Rabbits. In the study, 16 sires, 68 dams and offsprings obtained from these sires and dams were used in the first generation. Second generation was obtained by choosing 22 sires and 84 dams from the first generation offsprings. The variance components and heritabilities of live weight from weaning to 90th days were estimated by using ANOVA, ML and REML methods in two generations. Estimated heritabilites were found to be low and middle level. In addition, heritabilities estimated from dam variance components were higher than those estimated from sire variance components for all ages.
In this study, genetic diversity for agro-morphological traits in 52 landraces of sesame (Sesamum indicum L.) originated from Turkey was estimated through multivariate analysis. Populations evaluated for time to flowering, branching,... more
In this study, genetic diversity for agro-morphological traits in 52 landraces of sesame (Sesamum indicum L.)
originated from Turkey was estimated through multivariate analysis. Populations evaluated for time to flowering,
branching, capsule number per axil, carpel number per capsule, seed coat colour, capsule pubescence, capsule order,
plant height to first capsule, plant height, number of seeds per capsule, number of capsules on main stem, total
number of capsules per plant and 100 seed weight. This data set was reduced to 6 significant principle components
(PCs) that cumulatively explained 79% of the variance. The 6 retained PC scores were used as input for hierarchical
cluster analysis (Ward’s minumum variance). The populations were clustered in 4 different major groups according
to their similarity levels. In cluster analysis most of the populations of the South, Southeast and West regions tended
to cluster as outliers outside their region of adaptation. However, the distribution of Nortwest region populations was
according to their geographic origin. This study can help breeders better understand the genetic structure of Turkish
sesame populations which can be used for parental selection.
originated from Turkey was estimated through multivariate analysis. Populations evaluated for time to flowering,
branching, capsule number per axil, carpel number per capsule, seed coat colour, capsule pubescence, capsule order,
plant height to first capsule, plant height, number of seeds per capsule, number of capsules on main stem, total
number of capsules per plant and 100 seed weight. This data set was reduced to 6 significant principle components
(PCs) that cumulatively explained 79% of the variance. The 6 retained PC scores were used as input for hierarchical
cluster analysis (Ward’s minumum variance). The populations were clustered in 4 different major groups according
to their similarity levels. In cluster analysis most of the populations of the South, Southeast and West regions tended
to cluster as outliers outside their region of adaptation. However, the distribution of Nortwest region populations was
according to their geographic origin. This study can help breeders better understand the genetic structure of Turkish
sesame populations which can be used for parental selection.
In this study, whole blood potassium and haemoglobin (Hb) polymorphism were investigated in the Hair goats raised in the Antalya province. The separation of erythrocyte haemoglobin types was carried out using horizontal starch-gel... more
In this study, whole blood potassium and haemoglobin (Hb) polymorphism were investigated in the Hair goats raised in
the Antalya province. The separation of erythrocyte haemoglobin types was carried out using horizontal starch-gel electrophoresis
and the determination of the potassium level was done using an atomic absorption spectrometer in randomly chosen whole blood
samples of 188 Hair goats. The gene frequency for the higher potassium (KH) was 0.985±0.038. As a result of this research, two
haemoglobin gene alleles (HbA, HbB) were determined. The estimation of HbA allele gene frequency was 0.785±0.021. The Hair
goat population investigated in this study was not in equilibrium in terms of haemoglobin locus.
the Antalya province. The separation of erythrocyte haemoglobin types was carried out using horizontal starch-gel electrophoresis
and the determination of the potassium level was done using an atomic absorption spectrometer in randomly chosen whole blood
samples of 188 Hair goats. The gene frequency for the higher potassium (KH) was 0.985±0.038. As a result of this research, two
haemoglobin gene alleles (HbA, HbB) were determined. The estimation of HbA allele gene frequency was 0.785±0.021. The Hair
goat population investigated in this study was not in equilibrium in terms of haemoglobin locus.
Most animal breeding experiments are based on more than one economically important trait measured in each individual. In the statistical analysis of the resulting data, traits recorded in the same individuals are often considered one at a... more
Most animal breeding experiments are based on more than one economically important trait measured in each individual.
In the statistical analysis of the resulting data, traits recorded in the same individuals are often considered one at a time. Usually we
are interested, however, not only in the mode of inheritance of a particular trait but also in its relationships with other traits.
Multivariate analyses are required to make inferences about genetic and phenotypic correlations between traits, but point estimates
of such parameters can be poor even when breeding data on hundreds of animals are used. Bayesian methods exclude variance
matrices which are not within the parameter space, and make use of all the information on parameters in the likelihood function
and prior distribution, rather than just providing point estimates. In this study, a balanced one-way multiple-trait sire model
representing half-sib families is investigated using a Gibbs sampling approach with two different prior specifications. Inverse Wishart
distributions for the two variance matrices and a uniform distribution for the mean vector are used as priors. The results of Gibbs
sampling are compared with estimates of the parameters obtained from the analysis of variance method. It is shown that a Bayesian
analysis using a Gibbs sampling algorithm provides an estimate of the complete marginal posterior distribution of each unknown
parameter and also gives point estimates which are within the parameter space, in contrast to conventional procedures.
In the statistical analysis of the resulting data, traits recorded in the same individuals are often considered one at a time. Usually we
are interested, however, not only in the mode of inheritance of a particular trait but also in its relationships with other traits.
Multivariate analyses are required to make inferences about genetic and phenotypic correlations between traits, but point estimates
of such parameters can be poor even when breeding data on hundreds of animals are used. Bayesian methods exclude variance
matrices which are not within the parameter space, and make use of all the information on parameters in the likelihood function
and prior distribution, rather than just providing point estimates. In this study, a balanced one-way multiple-trait sire model
representing half-sib families is investigated using a Gibbs sampling approach with two different prior specifications. Inverse Wishart
distributions for the two variance matrices and a uniform distribution for the mean vector are used as priors. The results of Gibbs
sampling are compared with estimates of the parameters obtained from the analysis of variance method. It is shown that a Bayesian
analysis using a Gibbs sampling algorithm provides an estimate of the complete marginal posterior distribution of each unknown
parameter and also gives point estimates which are within the parameter space, in contrast to conventional procedures.
The main environmental effects in a mixed model are comparison or contemporary group effects or more precisely herdyear- month of calving subclass effects. The controversial subject of much discussion about the choice between treating... more
The main environmental effects in a mixed model are comparison or contemporary group effects or more precisely herdyear-
month of calving subclass effects. The controversial subject of much discussion about the choice between treating contemporary
group effects as fixed or as random has not still been settled in dairy cow evaluation. However, these effects are usually treated as
fixed since nonrandom associations between sires and herds may lead to biased predictions if herd-year-month effects are accounted
for as random. On the other hand, treating herd-year-month effects as random would increase the effective number of daughters
or the information with which an animal is being evaluated, and as a result of this, prediction error variance decreases. The main
purpose of this paper is to demonstrate the implementation of the Gibbs sampler with data on test day milk yields of dairy cows in
an unbalanced mixed half-sib sire model assuming random herd-year-month effects. An analysis of this kind employing the Gibbs
sampler with a very large data set containing records on 23.873 cows and 689 sires is carried out for the first time. Posterior
expectations of genetic and phenotypic parameters and functions of them are obtained from test day milk yields. The results of this
study are then compared with those of the previous study using the same data set but assuming fixed her-year-month effects.
month of calving subclass effects. The controversial subject of much discussion about the choice between treating contemporary
group effects as fixed or as random has not still been settled in dairy cow evaluation. However, these effects are usually treated as
fixed since nonrandom associations between sires and herds may lead to biased predictions if herd-year-month effects are accounted
for as random. On the other hand, treating herd-year-month effects as random would increase the effective number of daughters
or the information with which an animal is being evaluated, and as a result of this, prediction error variance decreases. The main
purpose of this paper is to demonstrate the implementation of the Gibbs sampler with data on test day milk yields of dairy cows in
an unbalanced mixed half-sib sire model assuming random herd-year-month effects. An analysis of this kind employing the Gibbs
sampler with a very large data set containing records on 23.873 cows and 689 sires is carried out for the first time. Posterior
expectations of genetic and phenotypic parameters and functions of them are obtained from test day milk yields. The results of this
study are then compared with those of the previous study using the same data set but assuming fixed her-year-month effects.
In biology, the objective of research scientists is to gain an understanding of biological relationships through experimentation. Statistical analyses are an essential part of biological research. Statistical methods used in biological... more
In biology, the objective of research scientists is to gain an understanding of biological relationships
through experimentation. Statistical analyses are an essential part of biological research.
Statistical methods used in biological research range from the very simple to the extremely complex.
Consequently, caution should be taken when selecting an appropriate statistical method. Data obtained
from plant-cell and tissue-culture studies can generally be placed into one of two or more groups. In
other words, a dependent variable consists of placing an observation into a category. The purpose of
this paper was to present statistical methods suitable for the analysis of binomial data obtained from
plant-tissue culture. First, there is an explanation of how the generalized linear models are obtained
and then an analysis of somatic-embryo germination data together with an interpretation of the
results.
through experimentation. Statistical analyses are an essential part of biological research.
Statistical methods used in biological research range from the very simple to the extremely complex.
Consequently, caution should be taken when selecting an appropriate statistical method. Data obtained
from plant-cell and tissue-culture studies can generally be placed into one of two or more groups. In
other words, a dependent variable consists of placing an observation into a category. The purpose of
this paper was to present statistical methods suitable for the analysis of binomial data obtained from
plant-tissue culture. First, there is an explanation of how the generalized linear models are obtained
and then an analysis of somatic-embryo germination data together with an interpretation of the
results.
The vec operator of a matrix X consists of stacking columns of X one under another in a single vector. The vech operator of a square matrix X is obtained in the same way that vecX is defined, but it starts each column at its diagonal... more
The vec operator of a matrix X consists of stacking columns of X one under another in a single vector. The vech operator
of a square matrix X is obtained in the same way that vecX is defined, but it starts each column at its diagonal element. The objective
of this paper is to describe vec and vech operators and apply them to a multivariate mixed sire model.
of a square matrix X is obtained in the same way that vecX is defined, but it starts each column at its diagonal element. The objective
of this paper is to describe vec and vech operators and apply them to a multivariate mixed sire model.
Estimates and posterior distributions of genetic and phenotypic variance matrices for test day milk records are obtained for 23 873 British Holstein-Friesian heifers, the progeny of 40 proven and 649 unproven sires, using restricted... more
Estimates and posterior distributions of genetic and phenotypic
variance matrices for test day milk records are obtained for 23 873
British Holstein-Friesian heifers, the progeny of 40 proven and 649
unproven sires, using restricted maximum likelihood (REML) and
Gibbs sampling methods with two different prior specifications in a
multivariate sire model. Results from the two methods are then
compared. The REML estimates and posterior expectations of
heritability and individual test day records range from 0.28 to 0.42.
Generally, heritabilities for test day records are lowest at the start and
highest in the second half of the lactation. Estimates of genetic
correlations between test day milk yields range from 0.59 to 0.99,
whilst those of phenotypic correlations are between 0.30 and 0.76, the
correlations being highest for adjacent tests. Bayesian inferences are
more informative, but require much more computer time.
variance matrices for test day milk records are obtained for 23 873
British Holstein-Friesian heifers, the progeny of 40 proven and 649
unproven sires, using restricted maximum likelihood (REML) and
Gibbs sampling methods with two different prior specifications in a
multivariate sire model. Results from the two methods are then
compared. The REML estimates and posterior expectations of
heritability and individual test day records range from 0.28 to 0.42.
Generally, heritabilities for test day records are lowest at the start and
highest in the second half of the lactation. Estimates of genetic
correlations between test day milk yields range from 0.59 to 0.99,
whilst those of phenotypic correlations are between 0.30 and 0.76, the
correlations being highest for adjacent tests. Bayesian inferences are
more informative, but require much more computer time.
Estimates of posterior distributions of genetic and phenotypic parameters and functions of them for individual test day milk yield are obtained for 28 873 British Holstein-Friesian heifers, the progeny of 40 proven and 649 unproven sires,... more
Estimates of posterior distributions of genetic and phenotypic
parameters and functions of them for individual test day milk yield
are obtained for 28 873 British Holstein-Friesian heifers, the progeny
of 40 proven and 649 unproven sires, using restricted maximum
likelihood (REML) and Gibbs sampling methods with a univariate
sire model. Results from the two methods are then compared. It is
found that the posterior expectations and REML estimates of the
parameters are fairly similar. The marginal posterior expectation and
REML estimate of heritability for lactation milk yield are 0.49 and
0.50, respectively. Heritability estimates for individual test day records
range from 0.27 to 0.40, whilst the posterior expectations are between
0.28 and 0.42. Generally, heritabilities for test day records were lowest
at the start and highest in the second half of the lactation. Gibbs
sampling requires substantially more computing than REML
estimation, but provides a more informative analysis.
parameters and functions of them for individual test day milk yield
are obtained for 28 873 British Holstein-Friesian heifers, the progeny
of 40 proven and 649 unproven sires, using restricted maximum
likelihood (REML) and Gibbs sampling methods with a univariate
sire model. Results from the two methods are then compared. It is
found that the posterior expectations and REML estimates of the
parameters are fairly similar. The marginal posterior expectation and
REML estimate of heritability for lactation milk yield are 0.49 and
0.50, respectively. Heritability estimates for individual test day records
range from 0.27 to 0.40, whilst the posterior expectations are between
0.28 and 0.42. Generally, heritabilities for test day records were lowest
at the start and highest in the second half of the lactation. Gibbs
sampling requires substantially more computing than REML
estimation, but provides a more informative analysis.
Markov chain Monte-Carlo methods are increasingly being applied to make inferences about the marginal posterior distributions of parameters in quantitative genetic models. This paper considers the application of one such method, Gibbs... more
Markov chain Monte-Carlo methods are increasingly being applied to make
inferences about the marginal posterior distributions of parameters in quantitative genetic
models. This paper considers the application of one such method, Gibbs sampling, to
Bayesian inferences about parameters in a normal mixed linear model when a restriction
is imposed on the relative values of the variance components. Two prior distributions
are proposed which incorporate this restriction. For one of them, the adaptive rejection
sampling technique is used to sample from the conditional posterior distribution of
a variance ratio. Simulated data from a balanced sire model are used to compare
different implementations of the Gibbs sampler and also inferences based on the two prior
distributions. Marginal posterior distributions of the parameters are illustrated. Numerical
results suggest that it is not necessary to discard any iterates, and that similar inferences
are made using the two prior specifications.
inferences about the marginal posterior distributions of parameters in quantitative genetic
models. This paper considers the application of one such method, Gibbs sampling, to
Bayesian inferences about parameters in a normal mixed linear model when a restriction
is imposed on the relative values of the variance components. Two prior distributions
are proposed which incorporate this restriction. For one of them, the adaptive rejection
sampling technique is used to sample from the conditional posterior distribution of
a variance ratio. Simulated data from a balanced sire model are used to compare
different implementations of the Gibbs sampler and also inferences based on the two prior
distributions. Marginal posterior distributions of the parameters are illustrated. Numerical
results suggest that it is not necessary to discard any iterates, and that similar inferences
are made using the two prior specifications.