1,899 research outputs found
Sources of Airborne Endotoxins in Ambient Air and Exposure of Nearby CommunitiesâA Review
Endotoxin is a bioaerosol component that is known to cause respiratory effects in exposed populations. To date, most research focused on occupational exposure, whilst much less is known about the impact of emissions from industrial operations on downwind endotoxin concentrations. A review of the literature was undertaken, identifying studies that reported endotoxin concentrations in both ambient environments and around sources with high endotoxin emissions. Ambient endotoxin concentrations in both rural and urban areas are generally below 10 endotoxin units (EU) mâ3; however, around significant sources such as compost facilities, farms, and wastewater treatment plants, endotoxin concentrations regularly exceeded 100 EU mâ3. However, this is affected by a range of factors including sampling approach, equipment, and duration. Reported downwind measurements of endotoxin demonstrate that endotoxin concentrations can remain above upwind concentrations. The evaluation of reported data is complicated due to a wide range of different parameters including sampling approaches, temperature, and site activity, demonstrating the need for a standardised methodology and improved guidance. Thorough characterisation of ambient endotoxin levels and modelling of endotoxin from pollution sources is needed to help inform future policy and support a robust health-based risk assessment process
Recommended Revisions to the National SEPâ1 Sepsis Quality Measure: A commentary by the Society of Infectious Diseases Pharmacists on the Infectious Diseases Society of America Position Paper
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154912/1/phar2384.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154912/2/phar2384_am.pd
A Controlled Study on the Characterisation of Bioaerosols Emissions from Compost
Bioaerosol emissions arising from biowaste treatment are an issue of public concern. To better characterise the bioaerosols, and to assess a range of measurement methods, we aerosolised green waste compost under controlled conditions. Viable and non-viable Andersen samplers, cyclone samplers and a real time bioaerosol detection system (Spectral Intensity Bioaerosol Sensor (SIBS)) were deployed simultaneously. The number-weighted fraction of fluorescent particles was in the range 22â26% of all particles for low and high emission scenarios. Overall fluorescence spectral profiles seen by the SIBS exhibited several peaks across the 16 wavelength bands from 298 to 735 nm. The size-fractionated endotoxin profile showed most endotoxin resided in the 2.1â9 ÎŒm aerodynamic diameter fraction, though up to 27% was found in a finer size fraction. A range of microorganisms were detected through culture, Matrix Assisted Laser Desorption and Ionisation Time of Flight Mass Spectrometry (MALDI-TOF) and quantitative polymerase chain reaction (qPCR), including Legionella pneumophila serogroup 1. These findings contribute to our knowledge of the physico-chemical and biological characteristics of bioaerosols from composting sites, as well as informing future monitoring approaches and data interpretation for bioaerosol measurement
Integrating team science into interdisciplinary graduate education: an exploration of the SESYNC Graduate Pursuit
Complex socio-environmental challenges require interdisciplinary, team-based research capacity. Graduate students are fundamental to building such capacity, yet formal opportunities for graduate students to develop these capacities and skills are uncommon. This paper presents an assessment of the Graduate Pursuit (GP) program, a formal interdisciplinary team science graduate research and training program administered by the National Socio-Environmental Synthesis Center (SESYNC). Quantitative and qualitative assessment of the programâs first cohort revealed that participants became significantly more comfortable with interdisciplinary research and team science approaches, increased their capacity to work across disciplines, and were enabled to produce tangible research outcomes. Qualitative analysis of four themesâ(1) discipline, specialization, and shared purpose, (2) interpersonal skills and personality, (3) communication and teamwork, and (4) perceived costs and benefitsâencompass participantsâ positive and negative experiences and support findings from past assessments. The findings also identify challenges and benefits related to individual personality traits and team personality orientation, the importance of perceiving a sense of autonomy and independence, and the benefit of graduate training programs independent of the university and graduate program environment
The link between volcanism and plutonism in epizonal magma systems; high-precision UâPb zircon geochronology from the Organ Mountains caldera and batholith, New Mexico
The Organ Mountains caldera and batholith expose the volcanic and epizonal plutonic record of an Eocene caldera complex. The caldera and batholith are well exposed, and extensive previous mapping and geochemical analyses have suggested a clear link between the volcanic and plutonic sections, making this an ideal location to study magmatic processes associated with caldera volcanism. Here we present high-precision thermal ionization mass spectrometry UâPb zircon dates from throughout the caldera and batholith, and use these dates to test and improve existing petrogenetic models. The new dates indicate that Eocene volcanic and plutonic rocks in the Organ Mountains formed from ~44 to 34 Ma. The three largest caldera-related tuff units yielded weighted mean [superscript 206]Pb/[superscript 238]U dates of 36.441 ± 0.020 Ma (Cueva Tuff), 36.259 ± 0.016 Ma (Achenback Park tuff), and 36.215 ± 0.016 Ma (Squaw Mountain tuff). An alkali feldspar granite, which is chemically similar to the erupted tuffs, yielded a synchronous weighted mean [superscript 206]Pb/[superscript 238]U date of 36.259 ± 0.021 Ma. Weighted mean [superscript 206]Pb/[superscript 238]U dates from the larger volume syenitic phase of the underlying Organ Needle pluton range from 36.130 ± 0.031 to 36.071 ± 0.012 Ma, and the youngest sample is 144 ± 20 to 188 ± 20 ka younger than the Squaw Mountain and Achenback Park tuffs, respectively. Younger plutonism in the batholith continued through at least 34.051 ± 0.029 Ma. We propose that the Achenback Park tuff, Squaw Mountain tuff, alkali feldspar granite and Organ Needle pluton formed from a single, long-lived magma chamber/mush zone. Early silicic magmas generated by partial melting of the lower crust rose to form an epizonal magma chamber. Underplating of the resulting mush zone led to partial melting and generation of a high-silica alkali feldspar granite cap, which erupted to form the tuffs. The deeper parts of the chamber underwent continued recharge and crystallization for 144 ± 20 ka after the final eruption. Calculated magmatic fluxes for the Organ Needle pluton range from 0.0006 to 0.0030 km3/year, in agreement with estimates from other well-studied plutons. The petrogenetic evolution proposed here may be common to many small-volume silicic volcanic systems
Structural genomics target selection for the New York consortium on membrane protein structure
The New York Consortium on Membrane Protein Structure (NYCOMPS), a part of the Protein Structure Initiative (PSI) in the USA, has as its mission to establish a high-throughput pipeline for determination of novel integral membrane protein structures. Here we describe our current target selection protocol, which applies structural genomics approaches informed by the collective experience of our team of investigators. We first extract all annotated proteins from our reagent genomes, i.e. the 96 fully sequenced prokaryotic genomes from which we clone DNA. We filter this initial pool of sequences and obtain a list of valid targets. NYCOMPS defines valid targets as those that, among other features, have at least two predicted transmembrane helices, no predicted long disordered regions and, except for community nominated targets, no significant sequence similarity in the predicted transmembrane region to any known protein structure. Proteins that feed our experimental pipeline are selected by defining a protein seed and searching the set of all valid targets for proteins that are likely to have a transmembrane region structurally similar to that of the seed. We require sequence similarity aligning at least half of the predicted transmembrane region of seed and target. Seeds are selected according to their feasibility and/or biological interest, and they include both centrally selected targets and community nominated targets. As of December 2008, over 6,000 targets have been selected and are currently being processed by the experimental pipeline. We discuss how our target list may impact structural coverage of the membrane protein space
Pseudopterosin synthesis from a chiral cross-conjugated hydrocarbon through a series of cycloadditions
The pseudopterosins are a family of diterpene marine natural products, which, by virtue of their interesting anti-inflammatory and analgesic properties, have attracted the attentions of many synthetic chemists. The most efficient syntheses reported to date are 14 and 20 steps in the longest linear sequence for chiral pool and enantioselective approaches, respectively, and all start with precursors that are easily mapped onto the natural product structure. Here, we describe an unconventional approach in which a chiral cross-conjugated hydrocarbon is used as the starting material for a series of three cycloadditions. Our approach has led to a significant reduction in the step count required to access these interesting natural products (10 steps chiral pool and 11 steps enantioselective). Furthermore it demonstrates that cross-conjugated hydrocarbons, erroneously considered by many to be too unstable and difficult to handle, are viable precursors for natural product synthesis
Fractures in sub-Saharan Africa: epidemiology, economic impact and ethnography (Fractures-E3): study protocol
Background: The population of older adults is growing in sub-Saharan Africa. Ageing exponentially increases fragility fracture risk. Of all global regions, Africa is projected to observe the greatest increase in fragility fractures. Fractures cause pain, disability and sometimes death, and management is expensive, often requiring complex healthcare delivery. For countries to plan future healthcare services, understanding is needed of fracture epidemiology, associated health service costs and the currently available healthcare resources. Methods: The Fractures-E3 5-year mixed-methods research programme will investigate the epidemiology, economic impact, and treatment provision for fracture and wider musculoskeletal health in The Gambia, South Africa and Zimbabwe. These three countries are diverse in their geography, degree of urbanisation, maturity of health service infrastructure, and health profiles. The programme comprises five study types: (i) population-based cross-sectional studies to determine vertebral fracture prevalence. Secondary outcomes will include osteoarthritis and sarcopenia. Age- and sex-stratified household sampling will recruit 5030 adults aged 40 years and older; (ii) prospective cohort studies in adults aged 40 years and older will determine hip fracture incidence, associated risk factors, and outcomes over one year (e.g. mortality, disability, health-related quality of life); (iii) economic studies of direct health costs of hip fracture with projection modelling of future national health costs and cost-effectiveness analyses of different hip fracture care pathways; (iv) national surveys of hip fracture services (including traditional bonesetters in The Gambia); and (v) ethnographic studies of hip fracture care provision and experiences will understand fracture service pathways. Conclusions: Greater understanding of current and expected fracture burdens, fracture risk factors, and existing fracture care provision, is intended to inform national clinical guidelines, health service policy and planning and future health service development in sub-Saharan Africa.</ns4:p
The Algerian Works of HĂ©lĂšne Cixous: at the Triple Intersection of European, North African and Religious Nationalisms
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