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Background: In epidemiological studies, samples are often collected long before disease onset or outcome assessment. Understanding the long-term stability of biomarkers measured in these samples is crucial. We estimated within-person stability over 10 years of metabolites and metabolite features (N=5938) in the Nurses' Health Study (NHS): The primary dataset included 1880 women with 1184 repeated samples donated 10 years apart while the secondary dataset included 1456 women with 488 repeated samples donated 10 years apart. Methods: We quantified plasma metabolomics using two liquid chromatography mass spectrometry platforms (lipids and polar metabolites) at the Broad Institute (Cambridge, MA). Intra-class correlations were used to estimate long-term stability (10 years) of metabolites and were calculated as the proportion of the total variability (within-person + between-person) attributable to between-person variability. Within-person variability was estimated among participants who donated two blood samples approximately 10 years apart while between-person variability was estimated among all participants. Results: In the primary dataset, the median ICC was 0.43 (1st quartile [Q1]: 0.36; 3rd quartile [Q3]: 0.50) among known metabolites and 0.41 (Q1: 0.34; Q3: 0.48) among unknown metabolite features. The most stable (median ICCs: 0.54-0.57) metabolite classes were nucleosides, nucleotides and analogues, phosphatidylcholine plasmalogens, diglycerides, and cholesteryl esters. The least stable (median ICCs: 0.26-0.36) metabolite classes were lysophosphatidylethanolamines, lysophosphatidylcholines and steroid and steroid derivatives. Results in the secondary dataset were similar (Spearman correlation=0.87) to corresponding results in the primary dataset. Conclusion: Within-person stability over 10 years is reasonable for lipid, lipid-related, and polar metabolites, and varies by metabolite class. Additional studies are required to estimate within-person stability over 10 years of other metabolites groups.

Cassava provides food security for millions of people worldwide. In Cote dIvoire, it is the second most important food crop. The objective of this study is to evaluate the structure and genetic variability of certain qualitative traits in targeted cassava landracesin order to identify the most widespread cassava landraces. Thus, prospecting missions were carried out in different regions of Cote dIvoire to characterize cassavalandraces, from which 180 cassava landrace accessions were characterized using14 morphological markers. Multiple Correspondence Analysis (MCA) showed that among the 14 markers, 10 were relevant fordescribing the total variability within accessions. In addition, the Hierarchical Ascending Classification (HAC) grouped the Ivorianlandraces into five homogeneous groups and also revealed that this morphological diversity is not structured according to the landracesgeographical origin. The study highlighted 131 distinct cultivars among the 180 accessions characterized. Moreover, of the 131 distinct cultivars, four were the most widespread. These are the local cultivars: Yace, Six mois, Blêbou and Trogla. Thus, the study has definitively shown that breeders have a wide choice of parents for developing improved cassava cultivars adapted fromthe populations found in Cote dIvoire.

Abstract The aim of this research was select the best combination of contrasting parents to develop a mapping population for drought tolerance, based on phenotypic and genotypic data. Phenotyping was conducted in a greenhouse during 16 days at vegetative stage under well-watered (WW) and water-deficit (WD) conditions. Traits evaluated were: gain of leaf area (GLA), total water use (TWU), net assimilation rate (NAR), water use efficiency (WUE) and transpiration rate (TR) response to vapor pressure deficit (VPD) (slope and breakpoint). Genotyping was performed with 127 SSR markers and a cluster analyses was conducted. An important interaction was observed for NAR, WUE and breakpoint in the VPD response. Under WD conditions, all genotypes showed lower GLA and TWU, whereas NAR and WUE increased its values. All genotypes showed reduction of the slope and breakpoint in high VPD response on WD. PCA analysis explains the 80% of the total variability. PC1 discriminated HA89 and R419 due to a lower slope and higher breakpoint, while PC2 separated by water treatment based on the WUE and TWU values. Nighty nine SSR marker were amplified detecting 262 alleles. Cluster analyzes showed two main groups, one including HAR4 and B59 and the other one including five remaining genotypes. According to these results, only R419xHA64 and HA89xHAR4 had a greater genetic distance (1.08), besides a high polymorphism level between ILs (about 60%). Therefore, we conclude that these would be the best combination of contrasting parents to develop mapping populations for drought tolerance in sunflower.

 The result of the Principal Component Analysis of southwest and northeast monsoon rainfall on the southern India plateau have been discussed. Monsoon rainfall data of five meteorological sub-divisions, i.e., Coastal Andhra Pradesh, Rayalseema, Tamilnadu, Interior parts of South Karnataka & Kerala, for a period of 33 years (1960-92), have been utilized. The results indicate that the rainfall of Coastal Andhra Pradesh and Rayalseema has maximum impact on first principal component of southwest monsoon rainfall of five meteorological sub-divisions. The study of only first principal component is sufficient in order to understand the 49% of total variability of southwest monsoon rainfall. Analysis of first three principal components is important to understand 85% of total variability of the rainfall of this season.   On the first principal component of northeast monsoon rainfall of aforesaid five meteorological sub-divisions the impact of the rainfall of Kerala and south interior Karnataka has been found maximum. In order to understand the 56% of total variability the analysis of first principal component is sufficient.   The special negative relation is found between northeast monsoon rainfall on the Coastal Andhra Pradesh and southwest monsoon rainfall of previous year on this very sub-division and Rayalseema. The principal components of southwest monsoon rainfall may prove useful for forecasting the northeast monsoon rainfall of southern Indian plateau.  

AbstractEpidemic outbreaks are extreme events that become more frequent and severe, associated with large social and real costs. It is therefore important to assess whether countries are prepared to manage epidemiological risks. We use a fully data-driven approach to measure epidemiological susceptibility risk at the country level using time-varying information. We apply both principal component analysis (PCA) and dynamic factor model (DFM) to deal with the presence of strong cross-section dependence in the data. We conduct extensive in-sample model evaluations of 168 countries covering 17 indicators for the 2010–2019 period. The results show that the robust PCA method accounts for about 90% of total variability, whilst the DFM accounts for about 76% of the total variability. Our index could therefore provide the basis for developing risk assessments of epidemiological risk contagion. It could be also used by organizations to assess likely real consequences of epidemics with useful managerial implications.

Abstract We examined short-term fluctuations of subjective age with data obtained from 123 young-old (Mage = 67.19 years) and 47 old-old adults (Mage = 86.59 years) who reported their momentary subjective age six times a day over seven consecutive days as they were going about their everyday lives. Participants felt younger on a large majority of occasions, and 25% of the total variability in subjective age could be attributed to within-person variation. Those with younger trait subjective ages exhibited larger moment-to-moment variation, while chronological age did not impact variability. Furthermore, we investigated relationships between within-day fluctuations of subjective age and daily cortisol fluctuations. Our findings extend the literature on subjective age by showing that how old people feel can vary on a momentary basis, that state and trait components of subjective age are related, and that fluctuations in subjective age are related to biomarkers of stress.

People with type 1 diabetes (T1D) are more likely to have depression than the general population and their prognosis is worse. Unfortunately, the characteristics of persons with T1D lead to inadequate screening for depression in this population. To aid in the detection of depression in this population, this study was undertaken to develop a depressive symptoms assessment instrument specific to patients with T1D and to examine its psychometric properties. A total of 207 people with T1D participated in this study. The reliability of the new scale was assessed using Cronbach’s alpha and the Spearman-Brown split-half coefficient. The Depression Inventory for type 1 Diabetes (DID-1), composed of 45 items on a Likert scale (1–7), shows high internal and temporal consistency, as well as adequate concurrent, convergent and discriminant validity. Factor analysis identified 7 factors (Symptoms of depression, Diminished interest, Hopelessness and dissatisfaction, Guilt, Fear, frustration and irritability, Defenselessness, and Interference in daily life) that explained 61.612% of the total variability. The cut-off score for diagnosis was set at 155 points. It was concluded that the DID-1 scale is a reliable, valid and useful tool for the assessment of depressive symptoms, eliminating the bias of other nonspecific diabetes scales.

The problem of criteria for distinguishing colonies from similar socio-demographic structures (mainly in terms of nesting density) is highly relevant and has remained in the focus of attention of ornithologists for a long time. The synchronization of reproduction in a colony is one of the criteria which require special development. Based on particular works (1972–2005), I present synchronization of the reproduction of gulls in colonies of different sizes. In contrast to previous studies, this paper uses a specially developed Index of Synchronization of Bird Breeding (Isr) to study this phenomenon, making it relatively easy to determine its level. The index distinguishes between different species of birds of this group: 75.7% (white-winged black tern) and 97.6% (black-headed gull) of the total variability of synchronization of breeding birds in colonies. Frequent failure of nesting attempts often causes repeated (compensatory) reproduction, which in the case of a mass manifestation significantly reduces the synchronization of the nesting period in colonies and thus significantly reduces this indicator. It is proved that a higher synchronization of reproduction characterizes small colonies (up to 50 nests). In all species of gulls, the beginning of reproduction in different colonies differs in terms of the appearance of the first eggs by 1–10 days and at the beginning of mass egg-laying – by 1–18 days. To the same extent, they differ in the timing of the hatching of eggs. In small colonies, the total egg-laying period is shorter by 34.9–49.7% compared to larger colonies. My observations show that large colonies are formed by the nesting of several small colonies on one plot. This phenomenon is noticeable during periods of mass re-nesting of birds after a high loss of nests (up to 69.5% or more) because of severe flooding. Differences in the breeding periods of colonies that differ in size appear when several small colonies with different breeding periods of birds are combined into one larger colony. This phenomenon is well detected in the formation of several sub-colonies and in the differences in the timing of reproduction of different parts of a large colony.

Abstract The main task of the investigation was to study the interrelations and to single out the sustainable clusters which reflect the content of different chemical substances in fruit, but have a tendency of slight correlation between each other. All these should become a base for definition of combination of fruits and berries containing a balanced set of useful compounds. It will help to make a composition of special food production. More than 170 fruit varieties of 13 fruit and berry like crops (apple, pear, apricot, plum, cherry, strawberry, black currant, red currant, viburnum, sea-buckhorn, honeysuckle) were studied for chemical indices content in their fruits and berries. The composition of chemical substances was chosen takng into account the specific features of all the investigated crops (dietary fiber, ascorbic acid, malic acid, citric acid, glucose, fructose, sucrose, Na, K, Ca, Mg, Fe, Cu, Zn). In order to study the correlation of the substances in the content, the principal component analysis was applied. As a result of the research, five clusters of the interrelated characters were singled out, these ones were linked to the first 5 the most important principal components. These components account for 78.23% of total variability of traits. The first component which accounts for 25.46% of total variability of traits is closely correlated with dietary fiber and organic acids content. The second component which accounts for 18.20% of total variability is closely connected with Ca, Fe, Zn content. The third component is correlated with Na, K, fructose and glucose contents.

Abstract. Sofiyanti N, Sari AK, Iriani D, Mutrofin R, Taufiq I, Juliantari E, Pranata S. 2021. Morphological and anatomical study of four Pyrrosia (Polypodiaeae) species from Rumbai forest, Riau Province, Indonesia. Biodiversitas 22: 4905-4914. Pyrrosia is one of genera in Polypodiaceae that is commonly distributed at Riau Forest, Indonesia. However, the detailed morphological characteristics and anatomical study of Pyrrosia in this region is scanty. This study was aimed to characterize the morphology and anatomy of four Pyrrosia species (P. angustata, P. lanceolata, P. nipoboloides and P. piloselloides) from Rumbai Forest, Riau Province. All of the specimens were collected in the field. Morphological characters were examined in detail. Anatomical preparation was conducted using the paraffin method. The specimens were then observed and photographed using a light microscope. Principal Component Analysis had been carried out using a total of 52 morphological and anatomical characters. The result showed the morphological variation among the species, especially on the shape of sterile lamina and sori characteristics. Anatomically, the examined species showed variations in outline shape in the transverse section of rhizomes and stipes, schelerenchymatous sheath and strand, as well as number of meristele. The PCA results showed that only three characters (shape of sterile laminae, base of sterile laminae, and upper surface color of sterile laminae) have eigenvalue over 1.00 and together these explain 100% of the total variability of the data. The anatomical data in this study is reported for the first time on Pyrrosia from Riau province.