direct selection
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Increasing productivity through continued animal genetic improvement is a crucial part of implementing sustainable livestock intensification programs. In Zebu cattle, the lack of sexual precocity is one of the main obstacles to improving beef production efficiency. Puberty-related traits are complex, but large-scale data sets from different “omics” have provided information on specific genes and biological processes with major effects on the expression of such traits, which can greatly increase animal genetic evaluation. In addition, genetic parameter estimates and genomic predictions involving sexual precocity indicator traits and productive, reproductive, and feed-efficiency related traits highlighted the feasibility and importance of direct selection for anticipating heifer reproductive life. Indeed, the case study of selection for sexual precocity in Nellore breeding programs presented here show that, in 12 years of selection for female early precocity and improved management practices, the phenotypic means of age at first calving showed a strong decreasing trend, changing from nearly 34 to less than 28 months, with a genetic trend of almost −2 days/year. In this period, the percentage of early pregnancy in the herds changed from around 10% to more than 60%, showing that the genetic improvement of heifer’s sexual precocity allows optimizing the productive cycle by reducing the number of unproductive animals in the herd. It has a direct impact on sustainability by better use of resources. Genomic selection breeding programs accounting for genotype by environment interaction represent promising tools for accelerating genetic progress for sexual precocity in tropical beef cattle.

The relevance of the work is due to the need to adapt the methods of the theory of optimal control to modern technical capabilities. The complexity of optimization of control systems by variational methods led to the creation of the N–i switching method. It is characterized by the simplicity of the mathematical apparatus, however, certain methodological aspects encourage research aimed at improving this method with a focus on software implementation. The purpose of this study is to develop the mathematical apparatus of the N–i switching method by developing a technique for correcting the settings of cascade structure relay systems for speed control of electric drives, based on the use of empirically obtained data. To achieve this goal, the following tasks were solved in the work: the parameters of the mathematical model of the electric drive were calculated, on which a series of numerical experiments were performed under the conditions of varying the calculated amplitude of the voltage of the power converter, which made it possible to reveal a stable pattern of changes in the speed of the system depending on the coefficient of the calculated voltage; built a calibration diagram, which is designed to determine the correction factor in the entire range of speed control. The revealed regularity is based on the indirect influence of the varied parameters on the conditions of controllers switching, the moments of occurrence and the nature of their sliding modes. The result of the work is a method for correcting the parameters of relay controllers, which brings the duration of the speed control of the electric drive closer to the empirically set optimal value. Its implementation does not require the involvement of large additional resources and provides an improvement in the quality of transient processes. The empirical component of the proposed optimization method consists not in the direct selection of one of the key parameters of the system, but in the preliminary refinement of the initial data, which is effective within the used synthesis method. The prospect of this study is an analytical solution to the problem of determining the correction coefficient, which will contribute to the practical application of the proposed optimization algorithm.

ABSTRACT Castor bean (Ricinus communis L.) is a plant native to Africa that presents important socioeconomic value for many countries, and has been the subject of breeding programs. In this context, the objective of this work was to identify genotypes with potential for improvement, focused on lowering plant height, using 19 hybrids and eight parents of R. communis. The study was developed at the experimental area of the Federal University of Recôncavo da Bahia in Cruz das Almas, BA, Brazil. The experiment was conducted in 2017 using a randomized block design with three replications, consisting of eight parents and 19 hybrids resulting from hybridization of these parents, grown with spacing of 3 meters between rows and 1 meter between plants. The characters stem diameter (SD), primary raceme insertion height (PRI), number of stem internodes (NSI), mean stem internode length (SIL), plant height (PH), number of harvested racemes (NHR), primary raceme length (PRL), and effective raceme length (ERL) were evaluated by analyzing the genetic parameters of variances and correlation between them. Five (H17, H2, H11, H13, and H6) of the 19 hybrids evaluated have potential to decrease PH of castor bean plants, presenting heights below 1.07 m. Direct selection for plant height is the most indicated for this purpose due to the high heritability of the character. However, the characters SD, PRI, and SIL stood out by assisting in indirect selection to decrease plant height because they can be early measured and present high heritability and strong correlation with PH.

Background: Setaria italica is an essential crop in the developing world and yield levels are low. To improve the yield, the utilization of diverse germplasm in a breeding program is vital. Methods: The present study aimed to characterize 50 genotypes in the first year and out of 50, 10 genotypes in the second year using multivariant traits. Wide variation was observed in both the qualitative and quantitative characteristics. Analysis of variance revealed the presence of significant differences for most symptoms. Higher estimates of GCV were followed for grain yields, followed by panicle lengths and organic outcomes. Higher estimates of PCV were observed for plant height and leaf length, followed by leaf width. Low GCV and PCV were recorded as leaf length, 50% flowering in days. PCV study indicated direct selection based on characters, panicle weight, test weight and strawweight showed a high and positive effect on grain yield per plant in both rainy and summer season indicating the proper relationship between these characters with grain yield per plant, which helps indirect selection for these traits thus in improving the grain yield per plant. Variability in foxtail millet germplasm allows plant breeders to effectively select specific donor lines for genetic improvement of foxtail millet. Result: Best 5 genotypes were found to be: Kangni-7 greater than Kangni-1 greater than Kangni-6 greater than Kangni-5 greater than Kangni-4.

Foeniculum vulgare Mill. (commonly known as fennel) is used in the pharmaceutical, cosmetic, and food industries. Fennel widely used as a digestive, carminative, galactagogue and diuretic and in treating gastrointestinal and respiratory disorders. Improving low heritability traits such as essential oil yield (EOY%) and trans-anethole yield (TAY%) of fennel by direct selection does not result in rapid gains of EOY% and TAY%. Identification of high-heritable traits and using efficient modeling methods can be a beneficial approach to overcome this limitation and help breeders select the most advantageous traits in medicinal plant breeding programs. The present study aims to compare the performance of the artificial neural network (ANN) and multilinear regression (MLR) to predict the EOY% and TAY% of fennel populations. Stepwise regression (SWR) was used to assess the effect of various input variables. Based on SWR, nine traits—number of days to 50% flowering (NDF50%), number of days to maturity (NDM), final plant height (FPH), number of internodes (NI), number of umbels (NU), seed yield per square meter (SY/m2), number of seeds per plant (NS/P), number of seeds per umbel (NS/U) and 1000-seed weight (TSW)—were chosen as input variables. The network with Sigmoid Axon transfer function and two hidden layers was selected as the final ANN model for the prediction of EOY%, and the TanhAxon function with one hidden layer was used for the prediction of TAY%. The results revealed that the ANN method could predict the EOY% and TAY% with more accuracy and efficiency (R2 of EOY% = 0.929, R2 of TAY% = 0.777, RMSE of EOY% = 0.544, RMSE of TAY% = 0.264, MAE of EOY% = 0.385 and MAE of TAY% = 0.352) compared with the MLR model (R2 of EOY% = 0.553, R2 of TAY% = 0.467, RMSE of EOY% = 0.819, RMSE of TAY% = 0.448, MAE of EOY% = 0.624 and MAE of TAY% = 0.452). Based on the sensitivity analysis, SY/m2, NDF50% and NS/P were the most important traits to predict EOY% as well as SY/m2, NS/U and NDM to predict of TAY%. The results demonstrate the potential of ANNs as a promising tool to predict the EOY% and TAY% of fennel, and they can be used in future fennel breeding programs.

<p>Children diagnosed with Autism Spectrum Disorder (ASD) who fail to develop functional speech are candidates for augmentative and alternative communication (AAC) systems. One of the primary intentions of AAC is to provide an alternative method of communicating in the absence of speech (Mirenda, 2003). In order to select the most beneficial AAC system for a user, in regards to the ease of acquisition and successfully communicating with AAC systems, it is considered important to undertake research comparing various AAC systems and to assess users’ preferences for using one system over another. Empirical evidence from previous studies comparing AAC indicates that users often learn to use AAC systems with varying degrees of proficiency and at various acquisition rates. Additionally, assessing users’ preferences for different AAC systems has been shown to influence acquisition rates and long term maintenance of AAC systems and is suggested to be an important component when carrying out AAC intervention.  In the present study a tangible symbol (TS) communication system was compared, in terms of acquisition rates and preference, with Picture Exchange (PE) and an additional direct selection (DS) method of gaining access to desired stimuli in two young boys with ASD. Two male participants diagnosed with ASD were taught via systematic instructional procedures to request/gain access to the continuation of preferred cartoon movies by using TS, PE, and DS. Additionally, preference assessments were implemented during intervention and follow-up phases to determine whether the participants showed a preference for using one of these three requesting/access methods over the other two, and whether any such preferences remained stable throughout follow-up sessions. Results indicated that both participants successfully learned to request each of the six cartoon movies using each of the three methods. Specifically, acquisition rates for TS and PE were comparable across both participants, and overall both participants preferred to request using the TS. During intervention sessions, one participant preferred to use DS, however this preference changed during follow-up where he chose to use TS more overall. These data suggest that TS is a viable AAC option for children with ASD who do not speak, and can be learned to a high proficiency after receiving systematic teaching procedures as used in the present study.</p>

<p>Children diagnosed with Autism Spectrum Disorder (ASD) who fail to develop functional speech are candidates for augmentative and alternative communication (AAC) systems. One of the primary intentions of AAC is to provide an alternative method of communicating in the absence of speech (Mirenda, 2003). In order to select the most beneficial AAC system for a user, in regards to the ease of acquisition and successfully communicating with AAC systems, it is considered important to undertake research comparing various AAC systems and to assess users’ preferences for using one system over another. Empirical evidence from previous studies comparing AAC indicates that users often learn to use AAC systems with varying degrees of proficiency and at various acquisition rates. Additionally, assessing users’ preferences for different AAC systems has been shown to influence acquisition rates and long term maintenance of AAC systems and is suggested to be an important component when carrying out AAC intervention.  In the present study a tangible symbol (TS) communication system was compared, in terms of acquisition rates and preference, with Picture Exchange (PE) and an additional direct selection (DS) method of gaining access to desired stimuli in two young boys with ASD. Two male participants diagnosed with ASD were taught via systematic instructional procedures to request/gain access to the continuation of preferred cartoon movies by using TS, PE, and DS. Additionally, preference assessments were implemented during intervention and follow-up phases to determine whether the participants showed a preference for using one of these three requesting/access methods over the other two, and whether any such preferences remained stable throughout follow-up sessions. Results indicated that both participants successfully learned to request each of the six cartoon movies using each of the three methods. Specifically, acquisition rates for TS and PE were comparable across both participants, and overall both participants preferred to request using the TS. During intervention sessions, one participant preferred to use DS, however this preference changed during follow-up where he chose to use TS more overall. These data suggest that TS is a viable AAC option for children with ASD who do not speak, and can be learned to a high proficiency after receiving systematic teaching procedures as used in the present study.</p>

<p class="042abstractstekst">Information on phenotypic variation helps to breed better varieties. Forty-nine bread wheat genotypes were evaluated in simple lattice design at Jamma and Geregera to determine the extent of variation and association among 11 traits. Analysis of variance showed significant differences (<em>p </em>&lt; 0.01) among the genotypes for all traits, indicating the presence of adequate variability. Maximum values of genotypic coefficients of variation were recorded for spike length (8.66 %), number of productive tillers (8.4 %), number of grains per spike (6.4 %) and thousand-seed mass (6.15 %); this also shows the presence of substantial variability for these traits. Genetic parameters of the study revealed that days to heading, plant height, spike length, number of grains per spike and thousand-seed mass had moderate to high heritability and genetic advance as percent of the mean. Therefore, direct selection could be practiced to improve bread wheat for these traits. Moreover, selection of early-cycle lines which can escape the negative effects of climate change will be possible. Grain yield had strong and significant positive correlation with thousand-seed mass (r_g= 0.395**), biological yield (r_gv= 0.617**) and harvest index (r_g= 0.731**); selection based on these traits will be most effective in future bread wheat yield improvement programs as they also exerted strong positive direct effects on grain yield.</p>

India is a nation which has got huge scope for modernization. The pace of increasing modernization in India coupled with its ever increasing human population is posing a very serious impact on environment mainly due to global warming. Abrupt rainfall conditions coupled with drought conditions prevailing during the Kharif season often hampers paddy transplantation in eastern parts of India. It results in late harvesting of paddy which in turn leads to late sowing of mustard crop in the fields during Rabi season. Hence, the need of the hour is to develop Indian mustard varieties having high yield potential as well as suitable for late sown conditions in Eastern India. An investigation was carried out to study the genetic variability, correlation and path analysis of ten quantitative traits in 33 genotypes of Indian mustard procured from diverse agro-climatic zones of the country. Analyses of variance were found to be highly significant for all the characters studied. Genotypic Coefficient of Variability as well as Phenotypic Coefficient of Variability were found high for number of primary branches, number of secondary branches, number of siliqua and seed yield per plot. High heritability coupled with higher genetic advance was found for plant height, number of siliqua per plant and seed yield per plot suggesting due importance of these traits for selection in breeding program.The phenotypic and genotypic correlation studies revealed that seed yield per plot exhibited significant positive correlation with plant height, number of primary branches per plant, number of secondary branches per plant, number of siliqua per plant, siliqua length, seeds per siliqua and 1000 seed-weight. Path coefficient analysis revealed that seed yield per plot, days to maturity, plant height, number of primary branch, number of secondary branch, number of siliqua per plant had positive direct effect on seed yield per plot suggesting that direct selection for these triats can be practiced for yield improvement in Indian mustard.

This article is devoted to issues of interaction of stakeholders of construction enterprises. First of all, the peculiarities of the construction industry are defined, which form additional requirements for the development of an integrated system for assessing interaction with stakeholders. Second, approaches to the formation of a register of potential stakeholders have been identified. A template for analysis has been developed, and individual examples are grouped by interaction directions. The methodology of identifying potential stakeholders by means of a three-level process of applying different versions of expert assessment methods in order to minimize their negative factor – subjectivity, is proposed. Methods of direct selection of experts and algorithms of their assessment are defined. Proposals to rank stakeholders according to their priority and potential result from their interaction with the construction enterprise have been developed. According to the integral assessment, ways of controlling the processes of interaction with stakeholders of different ranking levels are proposed, recommendations for building a further strategy for managing these processes are given. A system of modeling interaction between construction enterprises and stakeholders to ensure planning, organization, monitoring, and control processes in optimistic, realistic, and pessimistic scenarios has been created. Recommendations for further use of the methodology of integral assessment of the interaction of stakeholders of construction enterprises in practice are given.