High Arctic Mytilus spp.: occurrence, distribution and history of dispersal

Many marine species are known to change their distribution in response to changing climatic conditions. One such example is the blue mussel Mytilus spp., spreading northward coincident with an increase in ocean temperatures. On Svalbard, the frst living specimens of Mytilus spp. were discovered in 2004. Here we present an analysis of the current distribution of Mytilus spp. on Svalbard, with a focus on the west coast of Spitsbergen where strong Atlantifcation has been documented over the last few decades. We conducted diver-based surveys to develop a distributional map and to compare the current distribution with that of the Holocene. Furthermore, we investigate the recent history of recruitment of mussels on Svalbard to help identify invasion pathways. Our results show that blue mussels have been present on the archipelago at least since 2000 and are widespread along the west coast today. We also present evidence of local reproduction in one of the sites explored

Performance assessment off a commercial scale solar biomass hybrid dryer for quality seed maize production: Presentation

Though several maize varieties have been developed and introduced over the years in Ghana, farmers still face challenges of access to quality seed maize. Among the major constraints is lack of proper drying systems to quarantee quality of seed produced. Peculiar to most parts of Africa, drying of maize in the open, on bare ground along shoulders of roads is still a common practice in Ghana. In this study, a 5-tonne capacity solar biomass hybrid dryer was developed for drying maize for seed and food/feed in Ghana. Effect of drying air temperature in the dryer on the physiological quality and germination of maize kernels was investigated. Maize grains were dried in the open sun simulating farmers practice and using the dryer at 4 varying levels (L1, L2, L3 and L4) with corresponding heights (0.6m, 1.2m, 1.8m and 2.4m) respectively. Harvested maize at 22.8% moisture content was dried at the varying levels until reaching overall mean moisture content of 12.8 ± 0.2% (wb). Results showed that, drying air temperatures in the dryer increased in accordance with height with lowest mean temperature of 44.4 ± 4.6°C recorded at L1 and mean maximum of 52.8 ± 5.4 °C at L4. The increase in drying temperature at L4 increased kernel stress crack index by an average of 14% and reduced germination by 33%. However, drying temperatures at L1-L3 and in the open sun had no significant effect (p > 0.05) on the germination potential of maize grains. This satisfies the dryer’s potential to be used for drying maize grains for high quality seed production on commercial scale.Though several maize varieties have been developed and introduced over the years in Ghana, farmers still face challenges of access to quality seed maize. Among the major constraints is lack of proper drying systems to quarantee quality of seed produced. Peculiar to most parts of Africa, drying of maize in the open, on bare ground along shoulders of roads is still a common practice in Ghana. In this study, a 5-tonne capacity solar biomass hybrid dryer was developed for drying maize for seed and food/feed in Ghana. Effect of drying air temperature in the dryer on the physiological quality and germination of maize kernels was investigated. Maize grains were dried in the open sun simulating farmers practice and using the dryer at 4 varying levels (L1, L2, L3 and L4) with corresponding heights (0.6m, 1.2m, 1.8m and 2.4m) respectively. Harvested maize at 22.8% moisture content was dried at the varying levels until reaching overall mean moisture content of 12.8 ± 0.2% (wb). Results showed that, drying air temperatures in the dryer increased in accordance with height with lowest mean temperature of 44.4 ± 4.6°C recorded at L1 and mean maximum of 52.8 ± 5.4 °C at L4. The increase in drying temperature at L4 increased kernel stress crack index by an average of 14% and reduced germination by 33%. However, drying temperatures at L1-L3 and in the open sun had no significant effect (p > 0.05) on the germination potential of maize grains. This satisfies the dryer’s potential to be used for drying maize grains for high quality seed production on commercial scale

Benthic community structure, diversity, and productivity in the shallow Barents Sea bank (Svalbard Bank)

The Barents Sea is among the most productive areas in the world oceans, and its shallow banks exhibit particularly high rates of primary productivity reaching over 300 g C m−2year−1. Our study focused on the Svalbard Bank, an important feeding area for fishes and whales. In order to investigate how benthic community structure and benthic secondary production vary across environmental gradients and through time, we sampled across the bank and compared results with a similar study conducted 85 years ago. Considerable variability in community structure and function across bank corresponded with differences in the physical structure of the habitat, including currents, sedimentation regimes and sediment type, and overlying water masses. Despite an intensive scallop fishery and climatic shifts that have taken place since the last survey in the 1920s, benthic community structure was very similar to that from the previous survey, suggesting strong system resilience. Primary and secondary production over shallow banks plays a large role in the Barents Sea and may act as a carbon subsidy to surrounding fish populations, of which many are of commercial importance

Pharmacokinetics-pharmacodynamics of tazobactam in combination with cefepime in an in vitro infection model

We previously demonstrated that for tazobactam administered in combination with ceftolozane, the pharmacokinetic-pharmacodynamic (PK-PD) index that best described tazobactam efficacy was the percentage of the dosing interval that tazobactam concentrations were above a threshold (%T>threshold). Using data from studies of Enterobacteriaceae-producing ESBL, a relationship between tazobactam %T>threshold and reduction in log10 CFU from baseline, for which tazobactam threshold concentration was the product of the isolate's ceftolozane-tazobactam MIC value and 0.5, was identified. However, since the kinetics of cephalosporin hydrolysis vary among ESBLs and compounds, it is likely that the translational relationship to derive the tazobactam threshold concentration varies among enzymes and compounds. Using a one-compartment in vitro infection model, the PK-PD of tazobactam administered in combination with cefepime was characterized and a translational relationship across ESBL-producing Enterobacteriaceae was developed. Four clinical isolates, two Escherichia coli and two Klebsiella pneumoniae, known to produce CTX-M-15 β-lactamase enzymes and displaying cefepime MIC values of 2 to 4 mg/L in the presence of 4 mg/L tazobactam, were evaluated. Tazobactam threshold concentrations from 0.0625-1 times the tazobactam-potentiated cefepime MIC value were considered. The threshold that best described the relationship between tazobactam %T>threshold and change in log10 CFU from baseline was the product of 0.125 and the cefepime-tazobactam MIC (R2=0.813). The magnitude of %T>threshold associated with net bacterial stasis and a 1-log10 CFU/mL reduction from baseline at 24 hours was 21.9 and 52.8%, respectively. These data will be useful to support the identification of tazobactam dosing regimens in combination with cefepime for evaluation in future clinical studies

Supporting the Quadruple Aim Using Simulation and Human Factors During COVID-19 Care

This article is made available for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic.The health care sector has made radical changes to hospital operations and care delivery in response to the coronavirus disease (COVID-19) pandemic. This article examines pragmatic applications of simulation and human factors to support the Quadruple Aim of health system performance during the COVID-19 era. First, patient safety is enhanced through development and testing of new technologies, equipment, and protocols using laboratory-based and in situ simulation. Second, population health is strengthened through virtual platforms that deliver telehealth and remote simulation that ensure readiness for personnel to deploy to new clinical units. Third, prevention of lost revenue occurs through usability testing of equipment and computer-based simulations to predict system performance and resilience. Finally, simulation supports health worker wellness and satisfaction by identifying optimal work conditions that maximize productivity while protecting staff through preparedness training. Leveraging simulation and human factors will support a resilient and sustainable response to the pandemic in a transformed health care landscape

Reducing non-attendance rates for assessment at an eating disorders service: a quality improvement initiative

Rates of non-attendance at initial appointments within community eating disorder (ED) services are frequently high, although this has received relatively little research attention and no reports of interventions designed to address this. The current report describes outcomes following a change of procedure introducing a ‘partial booking’ system. Attendance rates at first appointments (N = 1260) were audited following introduction of a system designed to reduce non-attendance in January 2013 within a UK ED service. Rates were compared following implementation of the new system, using a historical control group for comparison, and showed a decline from 20.4 to 15.1%, a medium-sized effect. Use of a system asking patients to book an appointment reduced non-attendance at initial appointments and may be of use to similar services experiencing high non-attendance rates. Opt-in initiatives can reduce burden resulting from long waiting times and can be easily adapted to individual services

A Soluble Form of B Cell Maturation Antigen, a Receptor for the Tumor Necrosis Factor Family Member April, Inhibits Tumor Cell Growth

A proliferation-inducing ligand (APRIL) is a ligand of the tumor necrosis factor (TNF) family that stimulates tumor cell growth in vitro and in vivo. Expression of APRIL is highly upregulated in many tumors including colon and prostate carcinomas. Here we identify B cell maturation antigen (BCMA) and transmembrane activator and calcium modulator and cyclophilin ligand (CAML) interactor (TACI), two predicted members of the TNF receptor family, as receptors for APRIL. APRIL binds BCMA with higher affinity than TACI. A soluble form of BCMA, which inhibits the proliferative activity of APRIL in vitro, decreases tumor cell proliferation in nude mice. Growth of HT29 colon carcinoma cells is blocked when mice are treated once per week with the soluble receptor. These results suggest an important role for APRIL in tumorigenesis and point towards a novel anticancer strategy

Assisted evolution enables HIV-1 to overcome a high trim5α-imposed genetic barrier to rhesus macaque tropism

Diversification of antiretroviral factors during host evolution has erected formidable barriers to cross-species retrovirus transmission. This phenomenon likely protects humans from infection by many modern retroviruses, but it has also impaired the development of primate models of HIV-1 infection. Indeed, rhesus macaques are resistant to HIV-1, in part due to restriction imposed by the TRIM5α protein (rhTRIM5α). Initially, we attempted to derive rhTRIM5α-resistant HIV-1 strains using two strategies. First, HIV-1 was passaged in engineered human cells expressing rhTRIM5α. Second, a library of randomly mutagenized capsid protein (CA) sequences was screened for mutations that reduced rhTRIM5α sensitivity. Both approaches identified several individual mutations in CA that reduced rhTRIM5α sensitivity. However, neither approach yielded mutants that were fully resistant, perhaps because the locations of the mutations suggested that TRIM5α recognizes multiple determinants on the capsid surface. Moreover, even though additive effects of various CA mutations on HIV-1 resistance to rhTRIM5α were observed, combinations that gave full resistance were highly detrimental to fitness. Therefore, we employed an 'assisted evolution' approach in which individual CA mutations that reduced rhTRIM5α sensitivity without fitness penalties were randomly assorted in a library of viral clones containing synthetic CA sequences. Subsequent passage of the viral library in rhTRIM5α-expressing cells resulted in the selection of individual viral species that were fully fit and resistant to rhTRIM5α. These viruses encoded combinations of five mutations in CA that conferred complete or near complete resistance to the disruptive effects of rhTRIM5α on incoming viral cores, by abolishing recognition of the viral capsid. Importantly, HIV-1 variants encoding these CA substitutions and SIVmac239 Vif replicated efficiently in primary rhesus macaque lymphocytes. These findings demonstrate that rhTRIM5α is difficult to but not impossible to evade, and doing so should facilitate the development of primate models of HIV-1 infection

The Fate of Firms: Explaining Mergers and Bankruptcies

Using a uniquely complete data set of more than 50,000 observations of approximately 16,000 corporations, we test theories that seek to explain which firms become merger targets and which firms go bankrupt. We find that merger activity is much greater during prosperous periods than during recessions. In bad economic times, firms in industries with high bankruptcy rates are less likely to file for bankruptcy than they are in better years, supporting the market illiquidity arguments made by Shleifer and Vishny (1992). At the firm level, we find that, among poorly performing firms, the likelihood of merger increases with poorer performance, but among better performing firms, the relation is reversed and chances of merger increase with better performance. Such a changing relation has not been detected in prior merger studies. We also find that low-growth, resource-rich firms are prime acquisition targets and that firms’ debt capacity relates negatively to the likelihood of a merger. Debt-related variables, leverage and secured debt, play an especially prominent role in distinguishing between which firms merge and which firms go bankrupt