analysis of variation
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MAUSAM ◽  
2021 ◽  
Vol 47 (3) ◽  
pp. 259-268
Author(s):  
Y.E. A. RAJ

The thermodynamic structure of the atmosphere over coastal Tamilnadu during the northeast monsoon season has been studied in detail based on the daily 0000 UTC upper air data between 1000  and 500 hPa levels of Madras for October-January for the l0 year period 1976-77 to 1985-86. Normal upper  air soundings have been computed for dry and wet spells of northeast monsoon and for the brief period of southwest monsoon prior to northeast monsoon onset. The moisture flux crossing  Madras and the liquid  water content over Madras have been computed for various categories of monsoon activity. It has been shown that the onset of easterlies over Madras is accompanied by a cooling of 1C of the atmosphere over Madras at all levels upto 500 hPa. An east to west moisture flux of 21.1 x 108 metric tons per day across one degree wall over Madras has been found to cross coast during typical wet spell of northeast monsoon. The moisture flux crossing coast for good northeast monsoon and also the normal flux computed for the period of study compared fairly well with the moisture flux crossing west coast during southwest monsoon obtained in various other studies. The energy of an air column over coastal Tamilnadu was found to decrease subsequent to the onset of northeast monsoon. Analysis of variation of liquid water content revealed that even during deficit rainfall years there was considereable amount of low level moisture in  the atmosphere. Neither during dryspells of northeast monsoon nor after its retreat was there any clear sign of spreading of continental air mass over coastal Tamilnadu.  


Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2546
Author(s):  
José Javier Martín-Gómez ◽  
Diego Gutiérrez del Pozo ◽  
Ángel Tocino ◽  
Emilio Cervantes

Seed shape in species of the Cactaceae is described by comparison with geometric models. Three new groups of models are presented, two for symmetric seeds, and a third group for asymmetric seeds. The first two groups correspond, respectively, to superellipses and the combined equations of two semi-ellipses. The third group contains models derived from the representation of polar equations of Archimedean spirals that define the shape of asymmetric seeds in genera of different subfamilies. Some of the new models are geometric curves, while others are composed with a part resulting from the average silhouettes of seeds. The application of models to seed shape quantification permits the analysis of variation in seed populations, as well as the comparison of shape between species. The embryos of the Cactaceae are of the peripheral type, strongly curved and in contact with the inner surface of the seed coat. A relationship is found between seed elongation and the models, in which the genera with elongated seeds are represented by models with longer trajectories of the spiral. The analysis of seed shape opens new opportunities for taxonomy and allows quantification of seed shape in species of the Cactaceae.


Genetics ◽  
2021 ◽  
Author(s):  
Julie M Cridland ◽  
Alex C Majane ◽  
Li Zhao ◽  
David J Begun

Abstract Early work on de novo gene discovery in Drosophila was consistent with the idea that many such genes have male-biased patterns of expression, including a large number expressed in the testis. However, there has been little formal analysis of variation in the abundance and properties of de novo genes expressed in different tissues. Here we investigate the population biology of recently evolved de novo genes expressed in the D. melanogaster accessory gland, a somatic male tissue that plays an important role in male and female fertility and the post mating response of females, using the same collection of inbred lines used previously to identify testis-expressed de novo genes, thus allowing for direct cross tissue comparisons of these genes in two tissues of male reproduction. Using RNA-seq data we identify candidate de novo genes located in annotated intergenic and intronic sequence and determine the properties of these genes including chromosomal location, expression, abundance, and coding capacity. Generally, we find major differences between the tissues in terms of gene abundance and expression, though other properties such as transcript length and chromosomal distribution are more similar. We also explore differences between regulatory mechanisms of de novo genes in the two tissues and how such differences may interact with selection to produce differences in D. melanogaster de novo genes expressed in the two tissues.


Nutrients ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 3656
Author(s):  
Fokhrul Hossain ◽  
Samarpan Majumder ◽  
Justin David ◽  
Bruce A. Bunnell ◽  
Lucio Miele

Triple-negative breast cancer (TNBC) is an aggressive, molecularly heterogeneous subtype of breast cancer. Obesity is associated with increased incidence and worse prognosis in TNBC through various potential mechanisms. Recent evidence suggests that the gut microbiome plays a central role in the progression of cancer, and that imbalances or dysbiosis in the population of commensal microbiota can lead to inflammation and contribute to tumor progression. Obesity is characterized by low-grade inflammation, and gut dysbiosis is associated with obesity, chronic inflammation, and failure of cancer immunotherapy. However, the debate on what constitutes a “healthy” gut microbiome is ongoing, and the connection among the gut microbiome, obesity, and TNBC has not yet been addressed. This study aims to characterize the role of obesity in modulating the gut microbiome in a syngeneic mouse model of TNBC. 16S rRNA sequencing and metagenomic analyses were performed to analyze and annotate genus and taxonomic profiles. Our results suggest that obesity decreases alpha diversity in the gut microbiome. Metagenomic analysis revealed that obesity was the only significant factor explaining the similarity of the bacterial communities according to their taxonomic profiles. In contrast to the analysis of taxonomic profiles, the analysis of variation of functional profiles suggested that obesity status, tumor presence, and the obesity–tumor interaction were significant in explaining the variation of profiles, with obesity having the strongest correlation. The presence of tumor modified the profiles to a greater extent in obese than in lean animals. Further research is warranted to understand the impact of the gut microbiome on TNBC progression and immunotherapy.


2021 ◽  
Vol 20 (3) ◽  
pp. 16
Author(s):  
P. H. P. França ◽  
L.R.R. Da Silva

In this work, the effect on heat generation at the chip-machine tool interface was studied by varying the diameter of internal grooves of a tool for the turning process. This tool is modified with internal channels that circulate water as a coolant through a closed system. As an output parameter, the maximum cutting temperature at the chip-tool interface was studied. The input parameters were the thermal flux present at the chip-tool interface and the diameter of the internal channels present in the cutting tool. All the analysis of variation of the internal channels of the tools and also of the thermal flow exerted on the chip-tool interface were carried out using the finite element method by the Ansys® Workbench 19.2 software. The main one was that the variation in the diameter of the tool's internal grooves does not expressly impact the machining specifications.


2021 ◽  
Author(s):  
Chathurani Ranathunge ◽  
Melody Chimahusky ◽  
Mark E Welch

Microsatellites have long been considered non-functional, neutrally evolving regions of the genome. Recent findings suggest that they can function as drivers of rapid adaptive evolution. Previous work on common sunflower identified 479 transcribed microsatellites where allele length significantly correlates with gene expression (eSTRs) in a stepwise manner. Here, a population genetic approach is used to test whether eSTR allele length variation is under selection. Genotypic variation among and within populations at 13 eSTRs was compared with that at 19 anonymous microsatellites in 672 individuals from 17 natural populations of sunflower from across a cline running from Saskatchewan to Oklahoma. Expected heterozygosity, allelic richness, and allelic diversity were significantly lower at eSTRs, a pattern consistent with higher relative rates of purifying selection. Further, an analysis of variation in microsatellite allele lengths (lnRV), and heterozygosities (lnRH), indicate recent selective sweeps at the eSTRs. Mean microsatellite allele lengths at four eSTRs within populations are significantly correlated with latitude consistent with the predictions of the tuning knob model which predicts stepwise relationships between microsatellite allele length and phenotypes. This finding suggests that shorter or longer alleles at eSTRs may be favored in climatic extremes. Collectively, our results imply that eSTRs are likely under selection and that they may be playing a role in facilitating local adaptation across a well-defined cline in the common sunflower.


Languages ◽  
2021 ◽  
Vol 6 (3) ◽  
pp. 126
Author(s):  
Catherine E. Travis ◽  
Rena Torres Cacoullos

Are semantic classes of verbs genuine or do they merely mask idiosyncrasies of frequent verbs? Here, we examine the interplay between semantic classes and frequent verb-form combinations, providing new evidence from variation patterns in spontaneous speech that linguistic categories are centered on high frequency members to which other members are similar. We offer an account of the well-known favoring effect of cognition verbs on Spanish subject pronoun expression by considering the role of high-frequency verbs (e.g., creer ‘think’ and saber ‘know’) and particular expressions ((yo) creo ‘I think’, (yo) no sé ‘I don’t know’). Analysis of variation in nearly 3000 tokens of unexpressed and pronominal subjects in conversational data replicates well-established predictors, but highlights that the cognition verb effect is really one of 1sg cognition verbs. In addition, particular expressions stand out for their high frequency relative to their component parts (for (yo) creo, proportion of lexical type, and proportion of pronoun). Further analysis of 1sg verbs with frequent expressions as fixed effects reveals shared patterns with other cognition verbs, including an association with non-coreferential contexts. Thus, classes can be identified by variation constraints and contextual distributions that are shared among class members and are measurably different from those of the more general variable structure. Cognition verbs in variable Spanish subject expression form a class anchored in lexically particular constructions.


2021 ◽  
Vol 22 (13) ◽  
pp. 7073
Author(s):  
Arie Yehuda Curzon ◽  
Andrey Shirak ◽  
Ayana Benet-Perlberg ◽  
Alon Naor ◽  
Shay Israel Low-Tanne ◽  
...  

Oreochromis fishes exhibit variability of sex-determination (SD) genes whose characterization contributes to understanding of the sex differentiation network, and to effective tilapia farming, which requires all-male culture. However, O. niloticus (On) amh is the only master-key regulator (MKR) of SD that has been mapped (XY/XX SD-system on LG23). In O. aureus (Oa), LG3 controls a WZ/ZZ SD-system that has recently been delimited to 9.2 Mbp, with an embedded interval rich with female-specific variation, harboring two paics genes and banf2. Developing genetic markers within this interval and using a hybrid Oa stock that demonstrates no recombination repression in LG3, we mapped the critical SD region to 235 Kbp on the orthologous On physical map (p < 1.5 × 10−26). DNA-seq assembly and peak-proportion analysis of variation based on Sanger chromatograms allowed the characterization of copy-number variation (CNV) of banf2. Oa males had three exons capable of encoding 90-amino-acid polypeptides, yet in Oa females, we found an extra copy with an 89-amino-acid polypeptide and three non-conservative amino acid substitutions, designated as banf2w. CNV analysis suggested the existence of two to five copies of banf2 in diploidic Cichlidae. Disrupting the Hardy–Weinberg equilibrium (p < 4.2 × 10−3), banf2w was concordant with female determination in Oa and in three cichlids with LG3 WZ/ZZ SD-systems (O. tanganicae, O. hornorum and Pelmatolapia mariae). Furthermore, exclusive RNA-seq expression in Oa females strengthened the candidacy of banf2w as the long-sought LG3 SD MKR. As banf genes mediate nuclear assembly, chromatin organization, gene expression and gonad development, banf2w may play a fundamental role inducing female nucleus formation that is essential for WZ/ZZ SD.


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