Searching for an Anthropo(s)cene in the uplands of mid Wales

This essay presents the responses of four creative writers to the highly modified landscapes of the Cambrian Mountains in mid Wales. Through a tour of the historic mine site of Cwmystwyth and the dams of Cwm Elan, our aims were to engage with the concept of the Anthropocene in a landscape that could be emblematic of the proposed new geological interval. Through poems and prose inspired by these landscapes, the physical, social, cultural, and political processes shaping them are explored. The pieces have a strong sense of place, and touch on themes of pollution of the environment by heavy metals, geomorphological impacts of dams, and the human stories associated with those places. We demonstrate the great potential of such places and landscapes as sites where artistic creativity and science can engage and collaborate to find ways of communicating concepts such as the Anthropocene and the anthroposcenic

On the formation and evolution of black-hole binaries

We present the results of a systematic study of the formation and evolution of binaries containing black holes and normal-star companions with a wide range of masses. We first reexamine the standard formation scenario for close black-hole binaries, where the spiral-in of the companion in the envelope of a massive star causes the ejection of the envelope. We estimate the formation rates for different companion masses and different assumptions about the common-envelope structure and other model parameters. We find that black-hole binaries with intermediate- and high-mass secondaries can form for a wide range of assumptions, while black-hole binaries with low-mass secondaries can only form with apparently unrealistic assumptions (in agreement with previous studies). We then present detailed binary evolution sequences for black-hole binaries with secondaries of 2 to 17 Msun and demonstrate that in these systems the black hole can accrete appreciably even if accretion is Eddington limited (up to 7 Msun for an initial black-hole mass of 10 Msun) and that the black holes can be spun up significantly in the process. We discuss the implications of these calculations for well-studied black-hole binaries (in particular GRS 1915+105), ultra-luminous X-ray sources and Cygnus X-1. Finally, we discuss how some of the assumptions in the standard model could be relaxed to allow the formation of low-mass, short-period black-hole binaries which appear to be very abundant in Nature. (Abstract abridged)Comment: 21 pages, 9 figures, accepted by MNRAS, Figs. 2a/2b and 5 in very reduced forma

Stellar Mass Black Hole Binaries as ULXs

Ultraluminous X-ray sources (ULXs) with Lx > 10^{39} ergs/s have been discovered in great numbers in external galaxies with ROSAT, Chandra, and XMM. The central question regarding this important class of sources is whether they represent an extension in the luminosity function of binary X-ray sources containing neutron stars and stellar-mass black holes (BHs), or a new class of objects, e.g., systems containing intermediate-mass black holes (100-1000 Msun). We have carried out a theoretical study to test whether a large fraction of the ULXs, especially those in galaxies with recent star formation activity, can be explained with binary systems containing stellar-mass black holes. To this end, we have applied a unique set of binary evolution models for black-hole X-ray binaries, coupled to a binary population synthesis code, to model the ULXs observed in external galaxies. We find that for donor stars with initial masses >10 Msun the mass transfer driven by the normal nuclear evolution of the donor star is sufficient to potentially power most ULXs. This is the case during core hydrogen burning and, to an even more pronounced degree, while the donor star ascends the giant branch, though the latter phases lasts only ~5% of the main sequence phase. We show that with only a modest violation of the Eddington limit, e.g., a factor of ~10, both the numbers and properties of the majority of the ULXs can be reproduced. One of our conclusions is that if stellar-mass black-hole binaries account for a significant fraction of ULXs in star-forming galaxies, then the rate of formation of such systems is ~3 x 10^{-7} per year normalized to a core-collapse supernova rate of 0.01 per year.Comment: 15 pages, 12 figure

Towards a conceptual framework of beneficiary accountability by NGOs:An Indonesian case study

Beneficiary accountability (BA) by NGOs is a contested notion. Extant research suggests disparity and complexity over its meanings, practices and forms. Its operationalisation, although important, has been a challenge for the NGO scholars, practitioners, donors and the relevant policymakers. In this study, we offer a conceptual framework of BA based on extensive literature review. It highlights four key attributes of BA – casually demanded, action based, quasi-instrumental and focuses on beneficiary self-reliance. We then empirically illustrate the framework by drawing evidence from a case study. The data for this research has been collected via a fieldwork based case study in Indonesia and the methods employed include interviews, focus groups, observation and documentary analysis

Global overview of the management of acute cholecystitis during the COVID-19 pandemic (CHOLECOVID study)

Background: This study provides a global overview of the management of patients with acute cholecystitis during the initial phase of the COVID-19 pandemic. Methods: CHOLECOVID is an international, multicentre, observational comparative study of patients admitted to hospital with acute cholecystitis during the COVID-19 pandemic. Data on management were collected for a 2-month study interval coincident with the WHO declaration of the SARS-CoV-2 pandemic and compared with an equivalent pre-pandemic time interval. Mediation analysis examined the influence of SARS-COV-2 infection on 30-day mortality. Results: This study collected data on 9783 patients with acute cholecystitis admitted to 247 hospitals across the world. The pandemic was associated with reduced availability of surgical workforce and operating facilities globally, a significant shift to worse severity of disease, and increased use of conservative management. There was a reduction (both absolute and proportionate) in the number of patients undergoing cholecystectomy from 3095 patients (56.2 per cent) pre-pandemic to 1998 patients (46.2 per cent) during the pandemic but there was no difference in 30-day all-cause mortality after cholecystectomy comparing the pre-pandemic interval with the pandemic (13 patients (0.4 per cent) pre-pandemic to 13 patients (0.6 per cent) pandemic; P = 0.355). In mediation analysis, an admission with acute cholecystitis during the pandemic was associated with a non-significant increased risk of death (OR 1.29, 95 per cent c.i. 0.93 to 1.79, P = 0.121). Conclusion: CHOLECOVID provides a unique overview of the treatment of patients with cholecystitis across the globe during the first months of the SARS-CoV-2 pandemic. The study highlights the need for system resilience in retention of elective surgical activity. Cholecystectomy was associated with a low risk of mortality and deferral of treatment results in an increase in avoidable morbidity that represents the non-COVID cost of this pandemic

COVID-19 Social Science and Public Engagement Action Research in Vietnam, Indonesia and Nepal (SPEAR): Protocol for a mixed methods study exploring the experiences and impacts of COVID-19 for healthcare workers and vulnerable communities

Background: When the novel coronavirus – SARS-CoV-2 – started to spread globally, there was a call for social and behavioral scientists to conduct research to explore the wider socio-cultural contexts of coronavirus disease 2019 (COVID-19), to understand vulnerabilities, as well as to increase engagement within communities to facilitate adoption of public health measures. In this manuscript, we describe the protocol for a study conducted in Indonesia, Nepal, and Vietnam. In the study, we explore how the COVID-19 pandemic is affecting individuals and their communities. We focus on the wider health and economic impacts of COVID-19, in particular emerging and increased burden on mental health, as well as new or deepened vulnerabilities in the communities. The introduction of vaccines has added another layer of complexity and highlights differences in acceptance and inequalities around access.  Methods: We use mixed methods, combining survey methods and social media surveillance to gain a picture of the general situation within each country, with in-depth qualitative methods to gain a deeper understanding of issues, coupled with a synergistic engagement component. We also include an exploration of the role of social media in revealing or driving perceptions of the pandemic more broadly. Participants include health workers and members of communities from 13 sites across the three countries. Data collection is spread across two phases. Phase 1 is concerned with exploring lived experiences, impacts on working lives and livelihoods, mental health and coping strategies. Phase 2 is concerned with acceptance of COVID-19 vaccines, factors that increase and reduce acceptance, and factors that influence access. Conclusions: We will disseminate findings in multiple ways including short reports and policy briefs, articles in peer-reviewed journals, and digital diaries will be edited into short films and uploaded onto social media sites.</ns3:p

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P &lt; 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

Calcium-dependent inactivation of Cav1.3 calcium channels

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