Explore the vast range of titles available.

Black Americans are more likely to be essential workers due to racial capitalism. Because of the COVID-19 pandemic, essential workers are less able to adhere to social distancing and stay-at-home guidelines due to the nature of their work, because they are more likely to occupy crowded households, and are more likely to possess pre-existing health conditions. To assist Black essential workers in preventing infection or reducing the intensity of symptoms if contracted, vaccination against the virus is essential. Unfortunately, Black essential workers face considerable barriers to accessing vaccinations and are hesitant to receive the vaccine due to widespread misinformation and justified historical mistrust of the American medical system. The purpose of this work is to (1) describe the disproportionate impact of COVID-19 on Black essential workers due to racial capitalism, (2) outline the socioeconomic and racial barriers related to vaccination within this population, and (3) to suggest policy-related approaches to facilitate vaccination such as access to on-site vaccination opportunities, the funding of community outreach efforts, and the mandating of increased employee benefits.

This dissertation explores the pervasive effects of racial capitalism on the well-being of Black Americans across different age groups, investigating the mechanisms by which racial capitalism impacts their physical, mental, and socioeconomic health over the life course. Racial capitalism is defined as the interlocking systems of capitalism and racism, where capitalist economies and racial hierarchies converge to perpetuate and exploit racial disparities. Using constructivist grounded theory, this study engaged 27 Black Americans in interviews to understand their perspectives on the intersection of racism and capitalism, coping mechanisms, and views on reparations.The findings reveal a generational divide in the conceptualization of racial capitalism and its effects. Older Black Americans often view their experiences through lenses of personal resilience and historical progress, tending to disconnect the explicit links between racism and capitalism. In contrast, middle-aged Black Americans perceive a persistent social hierarchy that has adapted rather than diminished, recognizing ongoing systemic barriers despite social gains. Younger Black Americans express a critical awareness of racial capitalism, identifying it as an evolving and interlocking system that perpetuates socio-economic disparities through covert means.The study introduces the \"Racial Capitalism Life Course Theory,\" positing that racism and capitalism function as dual systems that cyclically reinforce socio-economic inequalities across the life course and generations. This theory aligns with established theories of life course and cumulative disadvantage, but provides critical interdisciplinary lens to examine the intersecting impacts of racism and economic systems over time.Policy implications of this research are vast and underscore the need for targeted interventions that address the specific challenges faced by each age cohort while considering the broader historical and socio-political context. The dissertation advocates for a grassroots, community-focused approach to reparations and policy reforms, aiming to address both historical injustices and current disparities, with a significant emphasis on educational, healthcare, and economic reforms to dismantle the structural underpinnings of racial capitalism.This comprehensive exploration contributes to the fields of sociology, gerontology, and public health by integrating age-specific impacts of racial capitalism into broader societal and policy contexts, offering a framework for addressing the compounded effects of racism and economic exploitation that Black Americans face throughout their lives.

Melanaphis sacchari (Zehntner, 1897) and Melanaphis sorghi (Theobald, 1904) are major worldwide crop pests causing direct feeding damage on sorghum and transmitting viruses to sugarcane. It is common in the scientific literature to consider these two species as synonyms, referred to as the ‘sugarcane aphid’, although no formal study has validated this synonymy. In this study, based on the comparison of samples collected from their whole distribution area, we use both morphometric and molecular data to better characterize the discrimination between M . sacchari and M . sorghi . An unsupervised multivariate analysis of morphometric data clearly confirmed the separation of the two species. The best discriminating characters separating these species were length of the antenna processus terminalis relative to length of hind tibia, siphunculus or cauda. However, those criteria sometimes do not allow an unambiguous identification. Bayesian clustering based on microsatellite data delimited two clusters, which corresponded to the morphological species separation. The DNA sequencing of three nuclear and three mitochondrial regions revealed slight divergence between species. In particular, the COI barcode region proved to be uninformative for species separation because one haplotype is shared by both species. In contrast, one SNP located on the nuclear EF1-α gene was diagnostic for species separation. Based on morphological and molecular evidence, the invasive genotype damaging to sorghum in the US, Mexico and the Caribbean since 2013 is found to be M . sorghi .

Most signals detected by genome-wide association studies map to non-coding sequence and their tissue-specific effects influence transcriptional regulation. However, key tissues and cell-types required for functional inference are absent from large-scale resources. Here we explore the relationship between genetic variants influencing predisposition to type 2 diabetes (T2D) and related glycemic traits, and human pancreatic islet transcription using data from 420 donors. We find: (a) 7741 cis -eQTLs in islets with a replication rate across 44 GTEx tissues between 40% and 73%; (b) marked overlap between islet cis- eQTL signals and active regulatory sequences in islets, with reduced eQTL effect size observed in the stretch enhancers most strongly implicated in GWAS signal location; (c) enrichment of islet cis- eQTL signals with T2D risk variants identified in genome-wide association studies; and (d) colocalization between 47 islet cis- eQTLs and variants influencing T2D or glycemic traits, including DGKB and TCF7L2 . Our findings illustrate the advantages of performing functional and regulatory studies in disease relevant tissues. Mechanistic inference following GWAS is hampered by the lack of tissue-specific transcriptomic resources. Here the authors combine genetic variants predisposing to type 2 diabetes with human pancreatic islet RNA-seq data. They identify 7741 islet expression quantitative trait loci (eQTLs), providing a resource for functional interpretation of association signals mapping to non-coding sequence.

The controlled use of fire was a breakthrough adaptation in human evolution. It first provided heat and light and later allowed the physical properties of materials to be manipulated for the production of ceramics and metals. The nalysis of tools at multiple sites shows that the source stone materials were systematically manipulated with fire to improve their flaking properties. Heat treatment predominates among silcrete tools at ∼72 thousand years ago (ka) and appears as early as 164 ka at Pinnacle Point, on the south coast of South Africa. Heat treatment demands a sophisticated knowledge of fire and an elevated cognitive ability and appears at roughly the same time as widespread evidence for symbolic behavior.

To optimise fecal sampling for reproducible analysis of the gut microbiome, we compared different methods of sample collection and sequencing of 16S rRNA genes at two centers. Samples collected from six individuals on three consecutive days were placed in commercial collection tubes (OMNIgeneGut OMR-200) or in sterile screw-top tubes in a home fridge or home freezer for 6–24 h, before transfer and storage at −80 °C. Replicate samples were shipped to centers in Australia and the USA for DNA extraction and sequencing by their respective PCR protocols, and analysed with the same bioinformatic pipeline. Variation in gut microbiome was dominated by differences between individuals. Minor differences in the abundance of taxa were found between collection-processing methods and day of collection, and between the two centers. We conclude that collection with storage and transport at 4 °C within 24 h is adequate for 16S rRNA analysis of the gut microbiome. Other factors including differences in PCR and sequencing methods account for relatively minor variation compared to differences between individuals.

In recognition of an increasing number of high-consequence infectious disease events, a group of subject-matter experts identified core safety principles that can be applied across all donning and doffing protocols for personal protective equipment.

Indo-Pacific lionfish have become invasive throughout the western Atlantic. Their predatory effects have been the focus of much research and are suggested to cause declines in native fish abundance and diversity across the invaded range. However, little is known about their non-consumptive effects, or their effects on invertebrates. Lionfish use shelters on the reef, thus there is potential for competition with other shelter-dwelling organisms. We demonstrate similar habitat associations between invasive lionfish, native spiny lobsters (Panulirus argus) and native long-spined sea urchins (Diadema antillarum), indicating the potential for competition. We then used a laboratory experiment to compare activity and shelter use of each species when alone and when lionfish were paired with each native species. Spiny lobsters increased their activity but did not change their shelter use in the presence of a lionfish, whilst long-spined sea urchins changed neither their activity nor shelter use. However, lionfish reduced their shelter use in the presence of spiny lobsters and long-spined sea urchins. This study highlights the importance not only of testing for the non-consumptive effects of invasive species, but also exploring whether native species exert non-consumptive effects on the invasive.

We present the first large-scale phylogenetic hypothesis for the genus Carex based on 996 of the 1983 accepted species (50.23%). We used a supermatrix approach using three DNA regions: ETS, ITS and matK. Every concatenated sequence was derived from a single specimen. The topology of our phylogenetic reconstruction largely agreed with previous studies. We also gained new insights into the early divergence structure of the two largest clades, core Carex and Vignea clades, challenging some previous evolutionary hypotheses about inflorescence structure. Most sections were recovered as non-monophyletic. Homoplasy of characters traditionally selected as relevant for classification, historical misunderstanding of how morphology varies across Carex, and regional rather than global views of Carex diversity seem to be the main reasons for the high levels of polyphyly and paraphyly in the current infrageneric classification.

The objectives of this study were to examine the relationship between residual feed intake (RFI) and DM and nutrient digestibility, in vitro methane production, and volatile fatty acid (VFA) concentrations in growing beef cattle. Residual feed intake was measured in growing Santa Gertrudis steers (Study 1; n = 57; initial BW = 291.1 ± 33.8 kg) and Brangus heifers (Study 2; n = 468; initial BW = 271.4 ± 26.1 kg) fed a high-roughage based diet (ME = 2.1 Mcal/kg DM) for 70 d in a Calan gate feeding barn. Animals were ranked by RFI based on performance and feed intake measured from d 0 to d 70 (Study 1) or d 56 (Study 2) of the trial, and 20 animals with the lowest and highest RFI were identified for subsequent collections of fecal and feed refusal samples for DM and nutrient digestibility analysis. In Study 2, rumen fluid and feces were collected for in vitro methane producing activity (MPA) and VFA analysis in trials 2, 3, and 4. Residual feed intake classification did not affect BW or BW gain (P 0.05), but low RFI steers and heifers consumed 19% less (P 0.01) DMI compared to high RFI animals. Steers with low RFI tended (P < 0.1) to have higher DM digestibility (DMD) compared to high RFI steers (70.3 vs. 66.5 ± 1.6% DM). Heifers with low RFI had 4% higher DMD (76.3 vs. 73.3 ± 1.0% DM) and 4 to 5% higher (P 0.01) CP, NDF, and ADF digestibility compared to heifers with high RFI. Low RFI heifers emitted 14% less (P < 0.01) methane (% GE intake; GEI) calculated according to Blaxter and Clapperton (1965) as modified by Wilkerson et al. (1995), and tended (P = 0.09) to have a higher rumen acetate:propionate ratio than heifers with high RFI (GEI = 5.58 vs. 6.51 ± 0.08 %; A:P ratio = 5.02 vs. 4.82 ± 0.14 %). Stepwise regression analysis revealed significant apparent nutrient digestibilites for Study 1 (DMD) and Study 2 (DMD and NDF digestibility), which accounted for an additional 8 (heifers) and 6% (steers) of the variation in intake when added to the base model (ADG and mid-test BW0.75). When DMD, NDF digestibility, and total ruminal VFA were added to the base model for Study 2- trials 2, 3, and 4, R2 increased from 0.33 to 0.47, explaining an additional 15% of the variation in DMI unrelated to growth and body size. Based on the results of these studies, differences in observed phenotypic RFI in growing beef animals may be a result of inter-animal variation in apparent nutrient digestibility and ruminal VFA concentrations.