117 research outputs found
Nutrient Management for Recirculating Hydroponics
Steady-state nutrient management is essential in hydroponic culture. Determination of an appropriate refill solution is attained using the principle of mass balance. Optimizing the ratio of nutrient elements and refill solution concentrations requires an understanding of the ratio of nutrients in tissue to water, which is measured as water use efficiency (WUE). This ratio is then multiplied by the desired concentration of nutrients in leaf tissue to determine the refill solution composition. Deep-flow hydroponics enables constant monitoring of solution parameters and root health. We have achieved a steady-state nitrogen concentration in solution by using an automated pH control system that adds a solution of 50 mM nitric acid and 200 mM ammonium sulfate. The pH remains stable throughout the life cycle as roots release a similar ratio of protons and hydroxide ions to balance uptake of either ammonium or nitrate. Daily monitoring of electrical conductivity (EC) guides adjustment of the refill solution concentration. A variable WUE and water to nutrient uptake ratio among species necessitates custom refill solutions. In our preliminary studies, wheat (Triticum aestivum) has a moderate WUE (3 g L-1) but ceases substantial nutrient uptake late in the lifecycle and the EC thus increases over time, causing nutrient accumulation in solution. Lettuce (Lactuca sativa) also has a moderate WUE (3 g L-1), and the EC of the solution remains stable. Tomato (Solanum lycopersicum) has a high WUE (6 g L-1), causing reduced EC and nutrient solution depletion. Monitoring solution compositions has allowed us to optimize the refill solution and acid addition concentration among species and lifecycle stages
Differences in Hospital Managers’, Unit Managers’, and Health Care Workers’ Perceptions of the Safety Climate for Respiratory Protection
This article compares hospital managers’ (HM), unit managers’ (UM), and health care workers’ (HCW) perceptions of respiratory protection safety climate in acute care hospitals. The article is based on survey responses from 215 HMs, 245 UMs, and 1,105 HCWs employed by 98 acute care hospitals in six states. Ten survey questions assessed five of the key dimensions of safety climate commonly identified in the literature: managerial commitment to safety, management feedback on safety procedures, coworkers’ safety norms, worker involvement, and worker safety training. Clinically and statistically significant differences were found across the three respondent types. HCWs had less positive perceptions of management commitment, worker involvement, and safety training aspects of safety climate than HMs and UMs. UMs had more positive perceptions of management’s supervision of HCWs’ respiratory protection practices. Implications for practice improvements indicate the need for frontline HCWs’ inclusion in efforts to reduce safety climate barriers and better support effective respiratory protection programs and daily health protection practices
From structure to crystallisation and pharmaceutical manufacturing: the CSD in CMAC Workflows
Two Workflows are presented that are relevant to the design and construction of end-to-end pharmaceutiucal manufacturing processes. The Workflows target the very early stage crystallisation aspect of these processes – production of the primary crystalline solid form – and relate to establishing decision-driven approaches for the screening for multi-component forms, specifically co-crystals, and to the use of additives to control crystal and primary particle form, notably morphology. These Workflows are shown to benefit from the use of the Million-plus structures in the Cambridge Structural Database and the associated structural informatics and analysis tools and are placed into the context of the work of the CMAC Future Manufacturing Hub
Diffusion Tensor Measures of the Corpus Callosum in Adolescents With Adolescent Onset Alcohol Use Disorders
In adults, myelination injury is associated with alcoholism. Maturation of the corpus callosum is prominent during adolescence. We hypothesized that subjects with adolescent-onset alcohol use disorders (AUD; defined as Diagnostic and Statistical Manual of Mental Disorders-IV alcohol dependence or abuse) would have myelination mircostructural differences compared to controls
ABA Criminal Justice Section Task Force on College Due Process Rights and Victim Protections: Recommendations for Colleges and Universities in Resolving Allegations of Campus Sexual Misconduct
The Executive Committee of the ABA Criminal Justice Section commissioned the Task Force on College Due Process Rights and Victim Protections in November 2016. Immediately after, extensive efforts were made to find members that represented all interested parties: victims, the accused, universities, other stakeholders, and national experts. The Task Force was fully constituted in the winter of 2017, and it ended up including two voting members who were originally liaisons from the ABA Commission on Domestic and Sexual Violence and the ABA Section of Civil Rights and Social Justice. This elevation was made in recognition of their significant contributions
A consensus statement on perinatal mental health during the COVID-19 pandemic and recommendations for post-pandemic recovery and re-build
Introduction: The COVID-19 pandemic posed a significant lifecourse rupture, not least to those who had specific physical vulnerabilities to the virus, but also to those who were suffering with mental ill health. Women and birthing people who were pregnant, experienced a perinatal bereavement, or were in the first post-partum year (i.e., perinatal) were exposed to a number of risk factors for mental ill health, including alterations to the way in which their perinatal care was delivered. Methods: A consensus statement was derived from a cross-disciplinary collaboration of experts, whereby evidence from collaborative work on perinatal mental health during the COVID-19 pandemic was synthesised, and priorities were established as recommendations for research, healthcare practice, and policy. Results: The synthesis of research focused on the effect of the COVID-19 pandemic on perinatal health outcomes and care practices led to three immediate recommendations: what to retain, what to reinstate, and what to remove from perinatal mental healthcare provision. Longer-term recommendations for action were also made, categorised as follows: Equity and Relational Healthcare; Parity of Esteem in Mental and Physical Healthcare with an Emphasis on Specialist Perinatal Services; and Horizon Scanning for Perinatal Mental Health Research, Policy, & Practice. Discussion: The evidence base on the effect of the pandemic on perinatal mental health is growing. This consensus statement synthesises said evidence and makes recommendations for a post-pandemic recovery and re-build of perinatal mental health services and care provision
Increased Inter-Colony Fusion Rates Are Associated with Reduced COI Haplotype Diversity in an Invasive Colonial Ascidian Didemnum vexillum
Considerable progress in our understanding of the population genetic changes associated with biological invasions has been made over the past decade. Using selectively neutral loci, it has been established that reductions in genetic diversity, reflecting founder effects, have occurred during the establishment of some invasive populations. However, some colonial organisms may actually gain an ecological advantage from reduced genetic diversity because of the associated reduction in inter-colony conflict. Here we report population genetic analyses, along with colony fusion experiments, for a highly invasive colonial ascidian, Didemnum vexillum. Analyses based on mitochondrial cytochrome oxidase I (COI) partial coding sequences revealed two distinct D. vexillum clades. One COI clade appears to be restricted to the probable native region (i.e., north-west Pacific Ocean), while the other clade is present in widely dispersed temperate coastal waters around the world. This clade structure was supported by 18S ribosomal DNA (rDNA) sequence data, which revealed a one base-pair difference between the two clades. Recently established populations of D. vexillum in New Zealand displayed greatly reduced COI genetic diversity when compared with D. vexillum in Japan. In association with this reduction in genetic diversity was a significantly higher inter-colony fusion rate between randomly paired New Zealand D. vexillum colonies (80%, standard deviation ±18%) when compared with colonies found in Japan (27%, standard deviation ±15%). The results of this study add to growing evidence that for colonial organisms reductions in population level genetic diversity may alter colony interaction dynamics and enhance the invasive potential of newly colonizing species
Macrophage gene expression associated with remodeling of the prepartum rat cervix:Microarray and pathway analyses
As the critical gatekeeper for birth, prepartum remodeling of the cervix is associated with increased resident macrophages (Mφ), proinflammatory processes, and extracellular matrix degradation. This study tested the hypothesis that expression of genes unique to Mφs characterizes the prepartum from unremodeled nonpregnant cervix. Perfused cervix from prepartum day 21 postbreeding (D21) or nonpregnant (NP) rats, with or without Mφs, had RNA extracted and whole genome microarray analysis performed. By subtractive analyses, expression of 194 and 120 genes related to Mφs in the cervix from D21 rats were increased and decreased, respectively. In both D21 and NP groups, 158 and 57 Mφ genes were also more or less up- or down-regulated, respectively. Mφ gene expression patterns were most strongly correlated within groups and in 5 major clustering patterns. In the cervix from D21 rats, functional categories and canonical pathways of increased expression by Mφ gene related to extracellular matrix, cell proliferation, differentiation, as well as cell signaling. Pathways were characteristic of inflammation and wound healing, e.g., CD163, CD206, and CCR2. Signatures of only inflammation pathways, e.g., CSF1R, EMR1, and MMP12 were common to both D21 and NP groups. Thus, a novel and complex balance of Mφ genes and clusters differentiated the degraded extracellular matrix and cellular genomic activities in the cervix before birth from the unremodeled state. Predicted Mφ activities, pathways, and networks raise the possibility that expression patterns of specific genes characterize and promote prepartum remodeling of the cervix for parturition at term and with preterm labor
Evaluating the Effects of SARS-CoV-2 Spike Mutation D614G on Transmissibility and Pathogenicity.
Global dispersal and increasing frequency of the SARS-CoV-2 spike protein variant D614G are suggestive of a selective advantage but may also be due to a random founder effect. We investigate the hypothesis for positive selection of spike D614G in the United Kingdom using more than 25,000 whole genome SARS-CoV-2 sequences. Despite the availability of a large dataset, well represented by both spike 614 variants, not all approaches showed a conclusive signal of positive selection. Population genetic analysis indicates that 614G increases in frequency relative to 614D in a manner consistent with a selective advantage. We do not find any indication that patients infected with the spike 614G variant have higher COVID-19 mortality or clinical severity, but 614G is associated with higher viral load and younger age of patients. Significant differences in growth and size of 614G phylogenetic clusters indicate a need for continued study of this variant
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