A binuclear vanadium oxyfluoride: di-μ-oxido-bis­[fluoridooxido(1,10-phenanthro­line)vanadium(V)]

The title compound, [V2F2O4(C12H8N2)2], is a centrosymmetric binuclear vanadium(V) species with the metal ions in a distorted octa­hedral environment. The symmetry-equivalent VV atoms exhibit coordination geometries defined by cis-terminal fluoride and oxide groups, unsymmetrically bridging oxide groups and the N-atom donors of the phenanthroline ligands. The crystal packing is stabilized by weak inter­molecular C—H⋯O and C—H⋯F hydrogen bonds

Global inequities and political borders challenge nature conservation under climate change

Underlying sociopolitical factors have emerged as important determinants of wildlife population trends and the effectiveness of conservation action. Despite mounting research into the impacts of climate change on nature, there has been little consideration of the human context in which these impacts occur, particularly at the global scale. We investigate this in two ways. First, by modeling the climatic niches of terrestrial mammals and birds globally, we show that projected species loss under climate change is greatest in countries with weaker governance and lower Gross Domestic Product, with loss of mammal species projected to be greater in countries with lower CO2 emissions. Therefore, climate change impacts on species may be disproportionately significant in countries with lower capacity for effective conservation and lower greenhouse gas emissions, raising important questions of international justice. Second, we consider the redistribution of species in the context of political boundaries since the global importance of transboundary conservation under climate change is poorly understood. Under a high-emissions scenario, we find that 35% of mammals and 29% of birds are projected to have over half of their 2070 climatic niche in countries in which they are not currently found. We map these transboundary range shifts globally, identifying borders across which international coordination might most benefit conservation and where physical border barriers, such as walls and fences, may be an overlooked obstacle to climate adaptation. Our work highlights the importance of sociopolitical context and the utility of a supranational perspective for 21st century nature conservation

Test@work: evaluation of workplace HIV testing for construction workers using the RE-AIM framework

Background: Community testing for HIV can reach previously untested populations but is rarely offered in workplaces. Targeting the construction sector could reach workers from high risk populations. Methods: The RE-AIM framework was used to evaluate Test@Work, a workplace HIV testing intervention for construction workers implemented at 21 events (10 companies) in the UK. Test@Work had three components: 1) an online health toolkit to inform managers about health screening and HIV testing; 2) general health checks; and 3) opt-in HIV consultation and testing. Quantitative data were collected using registration and exit questionnaires with workers (n= 426) and pre/post-event questionnaires with managers (n= 15), with qualitative analysis of free text responses. Results: Reach 426 individuals had health checks. Participants were broadly representative of the UK construction workforce, but with a higher proportion of permanent workers. Most workers reported being in good health but also believed their work had an adverse impact on their health. Effectiveness: 97% of health check participants opted to have a consultation about sexual health (n= 413) and 82% had an HIV test (n= 348), of whom 78% had not previously been tested. All HIV tests were non-reactive. HIV testing at work was considered acceptable by most participants. Participants reported learning new things about their health (74%), said they would make changes as a result (70%) and felt confident of success (median score 8/10). Adoption: Recruitment of companies was challenging and time consuming. Seven of the participating companies were very large, employing over 1000 workers, which is atypical of construction generally. Implementation: All events were completed as planned and were considered successful by all parties. Maintenance: All managers would arrange further events if they were offered them. Six managers incorporated sexual health awareness into their health programmes, but this was not possible for many as health agendas were set centrally by their organisations. Conclusions: Opt-in HIV testing, when embedded within a general health check, has high uptake and acceptability in the UK construction sector, and reaches individuals at risk for HIV who may not otherwise attend for testing. Cost-effectiveness of this approach is yet to be determined. Trial registration: ClinicalTrials.gov Identifier: NCT04292002

Purely-long-range bound states of He(2s3S)+(2s ^3S)+He(2p3P)(2p ^3P)

We predict the presence and positions of purely-long-range bound states of $^4$He$(2s ^3S)+{}^4$He$(2p ^3P)$ near the $2s ^3S_1+2p ^3P_{0,1}$ atomic limits. The results of the full multichannel and approximate models are compared, and we assess the sensitivity of the bound states to atomic parameters characterizing the potentials. Photoassociation to these purely-long-range molecular bound states may improve the knowledge of the scattering length associated with the collisions of two ultracold spin-polarized $^4$He$(2s ^3S)$ atoms, which is important for studies of Bose-Einstein condensates.Comment: 16 pages, 5 figure

Catalytic mechanism of alpha-phosphate attack in dUTPase is revealed by X-ray crystallographic snapshots of distinct intermediates, 31P-NMR spectroscopy and reaction path modelling.

Enzymatic synthesis and hydrolysis of nucleoside phosphate compounds play a key role in various biological pathways, like signal transduction, DNA synthesis and metabolism. Although these processes have been studied extensively, numerous key issues regarding the chemical pathway and atomic movements remain open for many enzymatic reactions. Here, using the Mason-Pfizer monkey retrovirus dUTPase, we study the dUTPase-catalyzed hydrolysis of dUTP, an incorrect DNA building block, to elaborate the mechanistic details at high resolution. Combining mass spectrometry analysis of the dUTPase-catalyzed reaction carried out in and quantum mechanics/molecular mechanics (QM/MM) simulation, we show that the nucleophilic attack occurs at the alpha-phosphate site. Phosphorus-31 NMR spectroscopy (31P-NMR) analysis confirms the site of attack and shows the capability of dUTPase to cleave the dUTP analogue alpha,beta-imido-dUTP, containing the imido linkage usually regarded to be non-hydrolyzable. We present numerous X-ray crystal structures of distinct dUTPase and nucleoside phosphate complexes, which report on the progress of the chemical reaction along the reaction coordinate. The presently used combination of diverse structural methods reveals details of the nucleophilic attack and identifies a novel enzyme-product complex structure

Can landscape-scale approaches to conservation management resolve biodiversity-ecosystem service trade-offs?

Conservation management is increasingly being required to support both the provision of ecosystem services and maintenance of biodiversity. However, trade-offs can occur between biodiversity and ecosystems services. We examine whether such trade-offs can be resolved through landscape-scale approaches to management. We analysed the biodiversity value and provision of selected ecosystem services (carbon storage, recreation, aesthetic and timber value) on patches of lowland heathland in the southern English county of Dorset. We used transition matrices of vegetation dynamics across 112 heathland patches to forecast biodiversity and ecosystem service provision on patches of different sizes over a 27-year timeline. Management scenarios simulated the removal of scrub and woodland and compared (i) no management (NM); (ii) all heaths managed equally (AM); and management focused on (iii) small heaths (SM) and (iv) large heaths (LM). Results highlighted a number of trade-offs. Whereas biodiversity values were significantly lower in woodland than in dry and humid heath, timber, carbon storage and aesthetic values were highest in woodland. While recreation value was positively related to dry heath area, it was negatively related to woodland area. Multicriteria analysis ranked NM highest for aesthetic value, carbon storage and timber value. In contrast, SM ranked highest for recreation and LM highest for biodiversity value. In no scenario did the current site-based approach to management (AM) rank highest. Synthesis and applications. Biodiversity-ecosystem service trade-offs are reported in lowland heathland, an ecosystem type of high conservation value. Trade-offs can be addressed through a landscape-scale approach to management, by varying interventions according to heathland patch size. Specifically, if management for biodiversity conservation is focused on larger patches, the aesthetic, carbon storage and timber value of smaller patches would increase, as a result of woody succession. In this way, individual heathland patches of either relatively high biodiversity value or high value for provision of ecosystem services could both potentially be delivered at the landscape scale

Ceramic on ceramic bearing fractures in total hip arthroplasty : an analysis of data from the national joint registry

Aims: Ceramic-on-ceramic (CoC) bearings in total hip arthroplasty (THA) are commonly used but concerns exist regarding ceramic fracture. This study aims to report the risk of revision for fracture of modern CoC bearings and identify factors that might influence this risk, using data from the National Joint Registry (NJR). Patients and Methods: We analysed data on 111,681 primary CoC THA’s and 182 linked revisions for bearing fracture recorded in NJR. We used implant codes to identify ceramic bearing composition and generated Kaplan-Meier estimates for implant survivorship. Logistic regression analyses were performed for implant size and patient specific variables to determine any associated risks for revision. Results: 99.8% of bearings were CeramTec Biolox® products. Revisions for fracture were linked to 7 of 79,442 (0.009%) Biolox® Delta heads, 38 of 31,982 (0.119%) Biolox® Forte heads, 101 of 80,170 (0.126%) Biolox® Delta liners and 35 of 31,258 (0.112%) Biolox® Forte liners. Regression analysis of implant size revealed smaller heads had significantly higher odds of fracture (χ2=68.0, p<0.0001). The highest fracture risk were observed in the 28mm Biolox® Forte subgroup (0.382%). There were no fractures in the 40mm head group for either ceramic type. Liner thickness was not predictive of fracture (p=0.67). BMI was independently associated with revision for both head fractures (OR 1.09 per unit increase, p=0.031) and liner fractures (OR 1.06 per unit increase, p=0.006). Conclusions: We report the largest study of CoC bearing fractures to date. The risk of revision for CoC bearing fracture is very low, however previous studies have underestimated this risk. There is good evidence that the latest generation of ceramic has greatly reduced the odds of head fracture but not of liner fracture. Small head size and high patient BMI are associated with an increased risk of ceramic bearing fracture

Biodiverse perennial meadows have aesthetic value and increase residents’ perceptions of site quality in urban green-space

We used photo-elicitation studies and a controlled perennial meadow creation experiment at ten urban green-spaces in southern England (five experimental sites and five control sites) to assess green-space visitors’ responses to urban meadows. Multiple meadows, which varied in their structural diversity (height) and plant species richness, were created at each experimental site. Photo elicitation demonstrated that meadows were generally preferred to herbaceous borders and formal bedding planting. Moreover, our experimental meadows had higher preference scores than a treatment that replicated mown amenity grassland, and meadow creation improved site quality and appreciation across a wide range of people. Meadows that contained more plant species and some structural diversity (i.e. were tall or of medium height) were most preferred. The magnitude of these preferences was lower amongst people that used the sites the most, probably due to a strong attachment to the site, i.e. sense of place. People with greater eco-centricity (i.e. those who used the countryside more frequently, had greater ability to identify plant species and exhibited more support for conservation) responded more positively to meadow vegetation. Crucially a wide range of respondents was willing to tolerate the appearance of meadows outside the flowering season, especially when provided with information on their biodiversity and aesthetic benefits and potential cost savings (from reduced cutting frequencies). Re-designing urban green-spaces and parks through the creation of species rich meadows can provide a win–win strategy for biodiversity and people, and potentially improve connections between the two