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BackgroundOne hypothesis for the function of sleep is that it serves as a mechanism to conserve energy. Recent studies have suggested that increased sleep can be an adaptive mechanism to improve survival under food deprivation in Drosophila melanogaster. To test the generality of this hypothesis, we compared sleep and its plastic response to starvation in a temperate and tropical population of Drosophila melanogaster.ResultsWe found that flies from the temperate population were more starvation resistant, and hypothesized that they would engage in behaviors that are considered to conserve energy, including increased sleep and reduced movement. Surprisingly, temperate flies slept less and moved more when they were awake compared to tropical flies, both under fed and starved conditions, therefore sleep did not correlate with population-level differences in starvation resistance. In contrast, total sleep and percent change in sleep when starved were strongly positively correlated with starvation resistance within the tropical population, but not within the temperate population. Thus, we observe unexpectedly complex relationships between starvation and sleep that vary both within and across populations. These observations falsify the simple hypothesis of a straightforward relationship between sleep and energy conservation. We also tested the hypothesis that starvation is correlated with metabolic phenotypes by investigating stored lipid and carbohydrate levels, and found that stored metabolites partially contributed towards variation starvation resistance.ConclusionsOur findings demonstrate that the function of sleep under starvation can rapidly evolve on short timescales and raise new questions about the physiological correlates of sleep and the extent to which variation in sleep is shaped by natural selection.

Transcriptomes may evolve by multiple mechanisms, including the evolution of novel genes, the evolution of transcript abundance, and the evolution of cell, tissue, or organ expression patterns. Here, we focus on the last of these mechanisms in an investigation of tissue and organ shifts in gene expression in Drosophila melanogaster. In contrast to most investigations of expression evolution, we seek to provide a framework for understanding the mechanisms of novel expression patterns on a short population genetic timescale. To do so, we generated population samples of D. melanogaster transcriptomes from five tissues: accessory gland, testis, larval salivary gland, female head, and first-instar larva. We combined these data with comparable data from two outgroups to characterize gains and losses of expression, both polymorphic and fixed, in D. melanogaster We observed a large number of gain- or loss-of-expression phenotypes, most of which were polymorphic within D. melanogaster Several polymorphic, novel expression phenotypes were strongly influenced by segregating cis-acting variants. In support of previous literature on the evolution of novelties functioning in male reproduction, we observed many more novel expression phenotypes in the testis and accessory gland than in other tissues. Additionally, genes showing novel expression phenotypes tend to exhibit greater tissue-specific expression. Finally, in addition to qualitatively novel expression phenotypes, we identified genes exhibiting major quantitative expression divergence in the D. melanogaster lineage.

We investigate simultaneous effects of finite system size and global charge conservation on thermal fluctuations in the vicinity of a critical point. For that we consider a finite interacting system, which exchanges particles with a finite reservoir (thermostat), comprising a statistical ensemble that is distinct from the common canonical and grand canonical ensembles. As a particular example the van der Waals model is used. The global charge conservation effects strongly influence the cumulants of particle number distribution when the system size is comparable to that of the reservoir. If the system size is large enough to capture all the physics associated with the interactions, the global charge conservation effects can be accurately described and corrected for analytically, within a recently developed subensemble acceptance method. The finite size effects start to play a significant role when the correlation length grows large due to proximity of the critical point or when the system is small enough to be comparable to an eigenvolume of an individual particle. We discuss our results in the context of fluctuation measurements in heavy-ion collisions.

By the empower of the technology and the Internet, there are huge amount of electronic text documents becoming available from day to day. Seeking information in the field of agriculture numerous collection is required well organized documentations that could be automated using text classification. Naïve Bayes, one of the most popular classification methods, is conducted with many languages such as English and Thai in order to do the classification such as post classification, document classification with preferable accuracy. In this paper, we will apply the Naïve Bayes method with Khmer full text search to improve the search result and user preference.

Natural populations often exist in spatially diverse environments and may experience variation in the strength and targets of natural selection across their ranges. Drosophila provides an excellent opportunity to study the effects of spatially varying selection in natural populations, as both Drosophila melanogaster and Drosophila simulans live across a wide range of environments in North America. Here, we characterize patterns of variation in transposable elements (TEs) from six populations of D. melanogaster and nine populations of D. simulans sampled from multiple latitudes across North America. We find a nearly twofold excess of TEs in D. melanogaster relative to D. simulans, with this difference largely driven by TEs segregating at the lowest and highest allele frequencies. We find no effect of latitude on either total TE abundance or average TE allele frequencies in either species. Moreover, we show that, as a class of mutations, the most common patterns of TE variation do not coincide with the sampled latitudinal gradient, nor are they consistent with local adaptation acting on environmental differences found in the most extreme latitudes. We also do not find a cline in ancestry for North American D. melanogaster-for either TEs or single nucleotide polymorphisms-suggesting a limited role for demography in shaping patterns of TE variation. Though we find little evidence for widespread clinality among TEs in Drosophila, this does not necessarily imply a limited role for TEs in adaptation. We discuss the need for improved models of adaptation to large-scale environmental heterogeneity, and how these might be applied to TEs.

While significant effort has been devoted to investigating the potential influence of spatially varying selection on genomic variation, relatively little effort has been devoted to experimental analysis of putative variants or genes experiencing such selection. Previous population genetic work identified an amino acid polymorphism in the Mnn1 gene as one of the most strongly latitudinally differentiated SNPs in the genome of Drosophila melanogaster in the United States and Australia. Here we report the results of our transgenic analysis of this amino acid polymorphism. Genotypes carrying alternative Mnn1 alleles differed in multiple phenotypes in a direction generally consistent with phenotypic differences previously observed along latitudinal clines. These results support inferences from earlier population genomic work that this variant influences fitness, and support the idea that the alleles exhibiting clines may be likely to have pleiotropic effects that are correlated along the axes favored by natural selection.

Burnout in social work is a long-standing professional issue. Social workers work tirelessly to provide empathetic care to clients and communities. However, stressful work conditions can contribute to burnout, vicarious trauma, and compassion fatigue. While burnout has been studied extensively within social work practice, new data is emerging about COVID-19’s unique impact on burnout among social workers. This review first discusses general factors that contribute to social workers’ experiences of burnout, and then explores how issues related to the COVID-19 pandemic exacerbated burnout for social workers. COVID-19 also provided a learning opportunity for how burnout can be mitigated. The review concludes with a call to action for next steps in both research and policy pertaining to social work and burnout. [ABSTRACT FROM AUTHOR]

Group B Streptococcus (GBS) asymptomatically colonises the vagina of up to 40% of pregnant women and can transmit to neonates during birth, causing neonatal pneumonia, sepsis, meningitis, and significant mortality. Vaginal GBS colonisation can be attributed to a range of host and bacterial factors, which may include the composition of the vaginal microbial community. There are few studies that have examined the vaginal community composition in relation to GBS colonisation throughout pregnancy. Here, we performed 16S rRNA sequencing (V3-V4) on vaginal swabs from women at 24- and 36-weeks' gestation, who were GBS culture-negative or GBS culture-positive at either 24 weeks or 36 weeks' gestation or at both timepoints. Vaginal swabs from 93 women were analysed; 46 women were culture-negative, 11 women GBS culture-positive at 24 weeks only, 21 women GBS culture-positive at 36 weeks only and 15 women GBS culture-positive at both timepoints on Brilliance GBS agar. V3-V4 16S rRNA gene amplicon sequencing demonstrated that in women that were GBS culture-positive at 36 weeks gestation only, G. vaginalis was significantly more abundant at 24-weeks' gestation despite a lack of significant changes in community richness between the 24- and 36-week samples. The vaginal microbial communities of women persistently colonised with GBS, had a significantly higher abundance of Lactobacillus iners, compared to other groups where L. crispatus, L. gasseri or L. jensenii were dominant. We have characterised the vaginal microbial community composition during pregnancy in relation to GBS colonisation status, in a longitudinal study for the first time. The most interesting finding was that in women that were persistently colonised with GBS throughout pregnancy, there was a significant increase in L. iners and significant reduction in L. crispatus abundance. Given the lack of detail of the role that the vaginal microbial community plays in GBS colonisation in the literature, it is imperative that the relationship between L. iners and GBS in this unique environmental niche is further investigated. [ABSTRACT FROM AUTHOR]

Pregnancy rates among youth experiencing homelessness are much higher than those of their housed peers, yet limited research exists on this population's abortion experiences. This study examined abortion attitudes, experiences, and decision making through individual interviews with 30 female, male, and gender-fluid youth (ages 18-21 years) experiencing homelessness. Respondents indicated that abortions are common in this population. Many youth also reported they either had, and/or knew of others, who had attempted abortions outside of the formal medical system while experiencing homelessness. Most youth noted that self-inductions resulted from not knowing where or how to access abortions safely, and as many feared stigma, judgment, and violence from family members and serious partners in response to obtaining abortions. Most youth reflected inaccurate perceptions regarding abortion cost, accessibility, and legality. Findings should be considered in developing socially contextualized family planning prevention and outreach efforts among this highly vulnerable youth population.