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Constructing an organizational identity with political ideology:The case of Huawei, 1987-2020
Get PDFLeveraging archival data, we study how Huawei used Chinese communist political ideology to construct its organizational identity. Covering the time from its founding in 1987 to 2020, we show how Huawei appropriated Fen Dou as a core idea-element of the Chinese communist political ideology to develop its identity as a “national industry revitalizer,” neutralized it as it internationalized and claimed to be an “international corporate citizen,” and then repurposed it as it sought to help advance all of humankind—akin to a “global technology leader.” By mapping the historical evolution of Huawei across different junctures and processual periods, we develop middle-range theory on the role of political ideology in identity construction. We contribute to the literature by introducing political ideology as a resource for identity construction, mapping the process of identity construction with ideology across different contexts, and articulating a resonant theoretical narrative whereby political ideology emerges as a double-edged sword. Our study reveals how political ideology helps create resonance with certain stakeholders, but how the commitment to a particular ideology carries meaningful risks.</p
Are ethnic inequalities in COVID-19 outcomes mediated by occupation risk?:Analyses of a 2-year record linked national cohort study in Scotland
Get PDFThis study investigated the extent to which ethnic inequalities in severe COVID-19 (i.e. hospitalization or deaths) are mediated through occupational risk differences. We used a population-based cohort study linking the 2011 Scottish Census to health records. We included all individuals aged 30-64 years and living in Scotland on 1 March 2020. The study period was from 1 March 2020 to 17 April 2022. Self-reported ethnicity was taken from the Census. We derived occupational risk of SARS-COV-2 infection using the 3-digit Standard Occupational Classification (SOC2010). We estimated hazard ratios (HRs) of total effects and controlled direct effects of ethnicity on severe COVID-19 mediated by occupational risk using marginal structural Cox models and subsequent proportional change. For aggregated ethnic groups, Non-White groups experienced a higher risk of severe COVID-19 (HR 1.6; 95% CI 1.4-1.8) compared to White group (all White ethnic groups) which increased to (1.7; 1.4-2.1) after accounting for occupational risk, representing a 6.0% change. For disaggregated ethnic groups, risks for South Asian (2.0; 1.8-2.3), African, Caribbean, or Black (1.3; 0.9-1.7) and Other ethnic groups (1.1; 0.9-1.3) were higher compared to White Scottish. After accounting for occupational risk, estimated risk of severe COVID-19 remained elevated for South Asian (1.8; 1.2-2.3), African Caribbean or Black (1.4; 0.8-2.1) and Other ethnic group (1.7; 1.1-2.3) representing a reduction of 11.8% and increases of 16.4% and 59.0%, respectively. Our findings suggest that ethnic inequalities in severe COVID-19 were impacted by differences in occupational risk.</p
Genetic diversity and population structure of Fasciola gigantica isolated from cattle in Malawi
Get PDFFasciola gigantica is an important trematode that affects the health of animals and humans in tropical and subtropical countries, including Malawi. Information on the genetic diversity and population structure of F. gigantica is important to understanding the parasite`s transmission patterns/ and in monitoring the development of resistance to commonly used anthelmintic agents. This study aimed to analyze the genetic diversity and population structure of Fasciola species collected from cattle at slaughter slabs and abattoirs in selected districts of Malawi. A total of 27 adult liver flukes were collected from cattle at slaughter slabs and abattoirs in the northern region (n = 12), central region (n = 5), and southern region (n = 10). The mitochondrial cytochrome c oxidase I (COI) gene and nicotinamide adenine dinucleotide dehydrogenase 1 (ND1) gene were amplified and the amplicons were sequenced for all samples. The sequences obtained were used to investigate genetic diversity through median-joining networks and phylogenetic analysis. Tajima’s D test and Fu’s Fs statistics were used to determine the population structure. Based on the analyzed COI and ND1 sequences, all samples were identified as F. gigantica. Single nucleotide polymorphisms (SNPs) were identified at 18 and 17 positions for COI and ND1 genes, resulting in 10 and 5 haplotypes, respectively. The haplotype diversities were 0.867 and 0.479 for COI and ND1 gene sequences, respectively. The population genetic structure indices showed a population that has undergone a recent expansion. This study provides baseline epidemiological data on the genetic diversity and population structure of F. gigantica in Malawi; which is important for its control.</p
Getting your ducks in a row:Marriage, protection, threat in Virginia
Get PDFMarriage, as a topic of ethnographic and historical exploration, ties together kinship, politics, economics, and faith in complex and significant ways. In the United States, federal and state governments have used legal marriage to create insiders and outsiders along lines of “race,” sexuality, and religion. Those who have not been allowed to marry a consenting partner of their choice have been cast as dangerous, and as threats to the nation. Drawing on fieldwork in the Virginia city of Charlottesville, I argue that protection is a key idiom through which to understand marriage and kinship in the United States. The research took place at the time of the 2017 white nationalist attack on Charlottesville, and discussions of marriage and kinship resonated with wider political questions about what it means to be safe, and how kinship often means loving against and caring against—protecting against—dangers that threaten those closest to us
CTCF-anchored chromatin loop dynamics during human meiosis
Get PDFDuring meiosis, the mammalian genome is organised within chromatin loops, which facilitate synapsis, crossing over and chromosome segregation, setting the stage for recombination events and the generation of genetic diversity. Chromatin looping is thought to play a major role in the establishment of cross overs during prophase I of meiosis, in diploid early primary spermatocytes. However, chromatin conformation dynamics during human meiosis are difficult to study experimentally, due to the transience of each cell division and the difficulty of obtaining stage-resolved cell populations. Here, we employed a machine learning framework trained on single cell ATAC-seq and RNA-seq data to predict CTCF-anchored looping during spermatogenesis, including cell types at different stages of meiosis. We find that chromatin loops do not orchestrate the gene expression dynamics seen during spermatogenesis, but loops do play important roles in recombination, influencing the positions of DNA breakage and cross over events
Incomplete recombination suppression fuels extensive haplotype diversity in a butterfly colour pattern supergene
Get PDFSupergenes can evolve when recombination-suppressing mechanisms like inversions promote co-inheritance of alleles at two or more polymorphic loci that affect a complex trait. Theory shows that such genetic architectures can be favoured under balancing selection or local adaptation in the face of gene flow, but they can also bring costs associated with reduced opportunities for recombination. These costs may in turn be offset by rare ‘gene flux’ between inverted and ancestral haplotypes, with a range of possible outcomes. We aimed to shed light on these processes by investigating the BC supergene, a large genomic region comprising multiple rearrangements associated with three distinct wing colour morphs in Danaus chrysippus, a butterfly known as the African monarch, African queen and plain tiger. Using whole-genome resequencing data from 174 individuals, we first confirm the effects of BC on wing colour pattern: background melanism is associated with SNPs in the promoter region of yellow, within an inverted subregion of the supergene, while forewing tip pattern is most likely associated with copy-number variation in a separate subregion of the supergene. We then show that haplotype diversity within the supergene is surprisingly extensive: there are at least six divergent haplotype groups that experience suppressed recombination with respect to each other. Despite high divergence between these haplotype groups, we identify an unexpectedly large number of natural recombinant haplotypes. Several of the inferred crossovers occurred between adjacent inversion ‘modules’, while others occurred within inversions. Furthermore, we show that new haplotype groups have arisen through recombination between two pre-existing ones. Specifically, an allele for dark colouration in the promoter of yellow has recombined into distinct haplotype backgrounds on at least two separate occasions. Overall, our findings paint a picture of dynamic evolution of supergene haplotypes, fuelled by incomplete recombination suppression
Carrier-Free Cisplatin-Dactolisib Nanoparticles for Enhanced Synergistic Antitumor Efficacy
Get PDFCisplatin (CDDP) is one of the most commonly used chemotherapeutic agents for solid tumors and hematologic malignancy. However, its therapeutic outcomes have remained unsatisfactory due to severe side effects, a short elimination half-life, the emergence of drug resistance, and the induction of metastasis. Combination with other chemotherapeutic agents has been proposed as one strategy to address the drawbacks of CDDP-based therapy. Therefore, this study aimed to boost the antitumor efficacy of cisplatin (CDDP) with a PI3K/mTOR dual inhibitor, dactolisib (BEZ), via a carrier-free codelivery system based on the self-assembly of the coordinated CDDP-BEZ. The synthesized CDDP-BEZ nanoparticles (NPs) possess sensitive pH-responsiveness, facilitating the delivery of both drugs to cancer cells. CDDP-BEZ NPs specifically enhanced cytotoxicity in cancer cells due to the synergy between cisplatin and dactolisib, resulting in augmented DNA damage, activation of mitochondria-dependent apoptosis, and increased inhibition on the PI3K/mTOR signaling axis. The inhibition of tumor migration and metastasis by CDDP-BEZ NPs was observed both in vitro and in vivo. Our data suggest that CDDP-BEZ NPs could serve as a safe and effective platform to maximize the synergy between both drugs in combating cancer, presenting a strategy to promote the therapeutic efficacy of platinum-based chemotherapeutic agents by combining them with PI3K inhibitors.</p
Insights from a methylome-wide association study of antidepressant exposure
No full textThis study tests the association of whole-blood DNA methylation and antidepressant exposure in 16,531 individuals from Generation Scotland (GS), using self-report and prescription-derived measures. We identify 8 associations and a high concordance of results between self-report and prescription-derived measures. Sex-stratified analyses observe nominally significant increased effect estimates in females for four CpGs. There is observed enrichment for genes expressed in the Amygdala and annotated to synaptic vesicle membrane ontology. Two CpGs (cg15071067; DGUOK-AS1 and cg26277237; KANK1) show correlation between DNA methylation with the time in treatment. There is a significant overlap in the top 1% of CpGs with another independent methylome-wide association study of antidepressant exposure. Finally, a methylation profile score trained on this sample shows a significant association with antidepressant exposure in a meta-analysis of eight independent external datasets. In this large investigation of antidepressant exposure and DNA methylation, we demonstrate robust associations which warrant further investigation to inform on the design of more effective and tolerated treatments for depression.</p
On ARGs, pedigrees, and genetic relatedness matrices
No full textGenetic relatedness is a central concept in genetics, underpinning studies of population and quantitative genetics in human, animal, and plant settings. It is typically stored as a genetic relatedness matrix (GRM), whose elements are pairwise relatedness values between individuals. This relatedness has been defined in various contexts based on pedigree, genotype, phylogeny, coalescent times, and, recently, ancestral recombination graph (ARG). ARG-based GRMs have been found to better capture the structure of a population and improve association studies relative to the genotype GRM. However, calculating GRMs and further operations with them is fundamentally challenging due to inherent quadratic time and space complexity. Here, we first discuss the different definitions of relatedness in a unifying context, making use of the additive model of a quantitative trait to provide a definition of "branch relatedness" and the corresponding "branch GRM". We explore the relationship between branch relatedness and pedigree relatedness through a case study of French-Canadian individuals that have a known pedigree. Through the tree sequence encoding of an ARG, we then derive an efficient algorithm for computing products between the branch GRM and a general vector, without explicitly forming the branch GRM. This algorithm leverages the sparse encoding of genomes with the tree sequence and hence enables large-scale computations with the branch GRM. We demonstrate the power of this algorithm by developing a randomized principal components algorithm for tree sequences that easily scales to millions of genomes. All algorithms are implemented in the open source tskit Python package. Taken together, this work consolidates the different notions of relatedness as branch relatedness and by leveraging the tree sequence encoding of an ARG it provides efficient algorithms that enable computations with the branch GRM that scale to mega-scale genomic datasets.</p
Isotopically heavy sulfur in nephelinite from Etinde, Cameroon Volcanic Line: Implications for the origin of intraplate magmatism
No full textIntraplate magmatism has traditionally been linked to anomalously hot mantle (hotspots) transported upwards from deep-sourced mantle plumes. However, many intraplate magmatic provinces lack convincing evidence for a mantle-plume origin, and the Cameroon Volcanic Line (CVL) located on the West African continental margin is one such province. Despite being active for ca. 65 million years, it lacks the time-progressive volcanic activity that would suggest the presence of a fixed mantle hotspot or plume; instead CVL magmatism has been linked to a shallow, enriched asthenospheric source. Etinde, a relatively young (<1 Ma) volcano located at the centre of the CVL on the continent-ocean boundary, is the most silica-undersaturated and incompatible element-enriched volcano in the region and forms the focus of this study. It is constructed almost entirely of feldspar-free nephelinite lava flows, with compositions ranging from olivine nephelinite to felsic leucite nephelinite. We report new sulfide-, sulfate- and bulk-δ34S data for a suite of Etinde rock samples; the first sulfur-isotope data for the CVL. Strong (~8 ‰) S-isotope fractionation between sulfide and sulfate (haüyne, nosean) phases suggest equilibration temperatures of ~600 °C, well below the magma solidus temperature and likely due to sub-solidus exsolution of nanoscale sulfide particles from the sulfate phenocryst phases. The most mafic samples from Etinde have been extensively degassed, containing less than 60 ppm sulfur, and therefore cannot be used to constrain the primary δ34S. Instead, we use the intermediate and felsic volcanic rocks, where sulfur is locked in phenocrysts of haüyne and nosean, respectively. Bulk δ34S of these rocks, which best represents the primary magmatic values, ranges from +3.7 ‰ to +6.3 ‰, a heavier signature than previously reported in alkaline igneous rocks. We propose that the heavy sulfur isotope values, together with the extreme silica undersaturation and incompatible element concentrations, reflect enrichment of the mantle source and fingerprint carbonate metasomatism in the mantle beneath the CVL. The heavy sulfur isotopic signature requires low-temperature fractionation and therefore implies the addition of sulfur through subduction processes. Our study has broad geochemical significance in contributing to a growing understanding of sulfur-isotope compositional variability in geochemically enriched mantle globally
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