Cool Companions to White Dwarfs from the 2MASS Second Incremental Data Release

We present near-infrared magnitudes for all white dwarfs (selected from the catalog of McCook & Sion) contained in the 2 Micron All Sky Survey Second Incremental Data Release(2MASS 2IDR). We show that the near-IR color-color diagram is an effective means of identifying candidate binary stars containing a WD and a low mass main sequence star. The loci of single WDs and WD + red dwarf binaries occupy distinct regions of the near-IR color-color diagram. We recovered all known unresolved WD + red dwarf binaries located in the 2IDR sky coverage, and also identified as many new candidate binaries (47 new candidates out of 95 total). Using observational near-IR data for WDs and M-L dwarfs, we have compared a sample of simulated WD + red dwarf binaries with our 2MASS data. The colors of the simulated binaries are dominated by the low mass companion through the late-M to early-L spectral types. As the spectral type of the companion becomes progressively later, however, the colors of unresolved binaries become progressively bluer. Binaries containing the lowest mass companions will be difficult to distinguish from single WDs solely on the basis of their near-IR colors.Comment: 18 pages, including 2 figures, accepted for publication in Ap

Gendered differences in perceptions and reports of wellbeing: A cross-sectional survey of adults on ART in Malawi

Few studies have examined gender differences in reported quality of life among persons living with HIV (PLWH) in low-income countries. We conducted a cross-sectional survey of adults on antiretroviral therapy in Malawi, including questions focused on wellbeing, and collected clinical data on these respondents. We compared men's and women's self-reported health and wellbeing using Poisson models that included socio-demographic covariates. Approximately 20% of respondents reported at least one physical functioning problem. In multiple variable models, men were significantly more likely to have a high viral load (≥200 copies/mL; aIRR 2.57), consume alcohol (aIRR 12.58), receive no help from family or friends (aIRR 2.18), and to feel worthless due to their HIV status (aIRR 2.40). Men were significantly less likely to be overweight or obese (aIRR 0.31), or report poor health (health today is not "very good;" aIRR 0.41). Taken together, despite higher prevalence of poor self-rated health, women were healthier across a range of objective dimensions, with better viral suppression, less alcohol use, and less social isolation (although they were more likely to have an unhealthy BMI). Research that includes multi-dimensional and gender-specific measurement of physical, mental and social health is important for improving our understanding of well-being of PLWH

Improving Patients' Understanding of Terms and Phrases Commonly Used in Self‐Reported Measures of Sexual Function

There is a significant gap in research regarding the readability and comprehension of existing sexual function measures. Patient-reported outcome measures may use terms not well understood by respondents with low literacy

Codesigning a Measure of Person-Centred Coordinated Care to Capture the Experience of the Patient: The Development of the P3CEQ

Background: Person-centred coordinated care (P3C) is a priority for stakeholders (ie, patients, carers, professionals, policy makers). As a part of the development of an evaluation framework for P3C, we set out to identify patient-reported experience measures (PREMs) suitable for routine measurement and feedback during the development of services. Methods: A rapid review of the literature was undertaken to identity existing PREMs suitable for the probing person-centred and/or coordinated care. Of 74 measures identified, 7 met our inclusion criteria. We critically examined these against core domains and subdomains of P3C. Measures were then presented to stakeholders in codesign workshops to explore acceptability, utility, and their strengths/weaknesses. Results: The Long-Term Condition 6 questionnaire was preferred for its short length, utility, and tone. However, it lacked key questions in each core domain, and in response to requests from our codesign group, new questions were added to cover consideration as a whole person, coordination, care plans, carer involvement, and a single coordinator. Cognitive interviews, on-going codesign, and mapping to core P3C domains resulted in the refinement of the questionnaire to 11 items with 1 trigger question. The 11-item modified version was renamed the P3C Experiences Questionnaire. Conclusions: Due to a dearth of brief measures available to capture people’s experience of P3C for routine practice, an existing measure was modified using an iterative process of adaption and validation through codesign workshops. Next steps include psychometric validation and modification for people with dementia and learning difficulties.</p

The influence of vector‐borne disease on human history: socio‐ecological mechanisms

Vector-borne diseases (VBDs) are embedded within complex socio-ecological systems. While research has traditionally focused on the direct effects of VBDs on human morbidity and mortality, it is increasingly clear that their impacts are much more pervasive. VBDs are dynamically linked to feedbacks between environmental conditions, vector ecology, disease burden, and societal responses that drive transmission. As a result, VBDs have had profound influence on human history. Mechanisms include: (1) killing or debilitating large numbers of people, with demographic and population-level impacts; (2) differentially affecting populations based on prior history of disease exposure, immunity, and resistance; (3) being weaponised to promote or justify hierarchies of power, colonialism, racism, classism and sexism; (4) catalysing changes in ideas, institutions, infrastructure, technologies and social practices in efforts to control disease outbreaks; and (5) changing human relationships with the land and environment. We use historical and archaeological evidence interpreted through an ecological lens to illustrate how VBDs have shaped society and culture, focusing on case studies from four pertinent VBDs: plague, malaria, yellow fever and trypanosomiasis. By comparing across diseases, time periods and geographies, we highlight the enormous scope and variety of mechanisms by which VBDs have influenced human history

Geminin Is Required for Zygotic Gene Expression at the Xenopus Mid-Blastula Transition

In many organisms early development is under control of the maternal genome and zygotic gene expression is delayed until the mid-blastula transition (MBT). As zygotic transcription initiates, cell cycle checkpoints become activated and the tempo of cell division slows. The mechanisms that activate zygotic transcription at the MBT are incompletely understood, but they are of interest because they may resemble mechanisms that cause stem cells to stop dividing and terminally differentiate. The unstable regulatory protein Geminin is thought to coordinate cell division with cell differentiation. Geminin is a bi-functional protein. It prevents a second round of DNA replication during S and G2 phase by binding and inhibiting the essential replication factor Cdt1. Geminin also binds and inhibits a number of transcription factors and chromatin remodeling proteins and is thought to keep dividing cells in an undifferentiated state. We previously found that the cells of Geminin-deficient Xenopus embryos arrest in G2 phase just after the MBT then disintegrate at the onset of gastrulation. Here we report that they also fail to express most zygotic genes. The gene expression defect is cell-autonomous and is reproduced by over-expressing Cdt1 or by incubating the embryos in hydroxyurea. Geminin deficient and hydroxyurea-treated blastomeres accumulate DNA damage in the form of double stranded breaks. Bypassing the Chk1 pathway overcomes the cell cycle arrest caused by Geminin depletion but does not restore zygotic gene expression. In fact, bypassing the Chk1 pathway by itself induces double stranded breaks and abolishes zygotic transcription. We did not find evidence that Geminin has a replication-independent effect on transcription. We conclude that Geminin is required to maintain genome integrity during the rapid cleavage divisions, and that DNA damage disrupts zygotic gene transcription at the MBT, probably through activation of DNA damage checkpoint pathways

Geminin-Deficient Neural Stem Cells Exhibit Normal Cell Division and Normal Neurogenesis

Neural stem cells (NSCs) are the progenitors of neurons and glial cells during both embryonic development and adult life. The unstable regulatory protein Geminin (Gmnn) is thought to maintain neural stem cells in an undifferentiated state while they proliferate. Geminin inhibits neuronal differentiation in cultured cells by antagonizing interactions between the chromatin remodeling protein Brg1 and the neural-specific transcription factors Neurogenin and NeuroD. Geminin is widely expressed in the CNS during throughout embryonic development, and Geminin expression is down-regulated when neuronal precursor cells undergo terminal differentiation. Over-expression of Geminin in gastrula-stage Xenopus embryos can expand the size of the neural plate. The role of Geminin in regulating vertebrate neurogenesis in vivo has not been rigorously examined. To address this question, we created a strain of Nestin-Cre/Gmnnfl/fl mice in which the Geminin gene was specifically deleted from NSCs. Interestingly, we found no major defects in the development or function of the central nervous system. Neural-specific GmnnΔ/Δ mice are viable and fertile and display no obvious neurological or neuroanatomical abnormalities. They have normal numbers of BrdU+ NSCs in the subgranular zone of the dentate gyrus, and GmnnΔ/Δ NSCs give rise to normal numbers of mature neurons in pulse-chase experiments. GmnnΔ/Δ neurosphere cells differentiate normally into both neurons and glial cells when grown in growth factor-deficient medium. Both the growth rate and the cell cycle distribution of cultured GmnnΔ/Δ neurosphere cells are indistinguishable from controls. We conclude that Geminin is largely dispensable for most of embryonic and adult mammalian neurogenesis

Repeated local emergence of carbapenem-resistant Acinetobacter baumannii in a single hospital ward.

We recently reported a dramatic increase in the prevalence of carbapenem-resistant Acinetobacter baumannii infections in the intensive care unit (ICU) of a Vietnamese hospital. This upsurge was associated with a specific oxa23-positive clone that was identified by multilocus VNTR analysis. Here, we used whole-genome sequence analysis to dissect the emergence of carbapenem-resistant A. baumannii causing ventilator-associated pneumonia (VAP) in the ICU during 2009-2012. To provide historical context and distinguish microevolution from strain introduction, we compared these genomes with those of A. baumannii asymptomatic carriage and VAP isolates from this same ICU collected during 2003-2007. We identified diverse lineages co-circulating over many years. Carbapenem resistance was associated with the presence of oxa23, oxa40, oxa58 and ndm1 genes in multiple lineages. The majority of resistant isolates were oxa23-positive global clone GC2; fine-scale phylogenomic analysis revealed five distinct GC2 sublineages within the ICU that had evolved locally via independent chromosomal insertions of oxa23 transposons. The increase in infections caused by carbapenem-resistant A. baumannii was associated with transposon-mediated transmission of a carbapenemase gene, rather than clonal expansion or spread of a carbapenemase-harbouring plasmid. Additionally, we found evidence of homologous recombination creating diversity within the local GC2 population, including several events resulting in replacement of the capsule locus. We identified likely donors of the imported capsule locus sequences amongst the A. baumannii isolated on the same ward, suggesting that diversification was largely facilitated via reassortment and sharing of genetic material within the localized A. baumannii population