992 research outputs found
Short-Term Transport Stress and Supplementation Alter Immune Function in Aged Horses
Long-distance transport is associated with stress-related changes in equine immune function, and shipping-associated illnesses are often reported. Horses are frequently transported short distances, yet the effects of short-term transport on immune function remain largely unknown. Twelve horses, aged 15–30 yr, were assigned to either the control (n = 6) or treatment (n = 6) groups; treatment horses received a daily antioxidant supplement 3 weeks before and after transport. All horses were transported for approximately 1.5–2 hr on Day 0. Blood was collected via jugular venipuncture at 15-min pre- and post-transport and on Days –21, 1, 3, 7, 14, and 21. Body temperature, heart rate, body weight, total cortisol, and gene expression of IFNγ, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12α, IL-17α, SAA1, and TNFα in whole blood were measured. Peripheral blood mononuclear cells were isolated, stimulated with PMA/ionomycin, and stained for IFNγ and TNFα before analysis via flow cytometry. Statistical analyses were performed with significance set at P \u3c 0.05 (SAS 9.4). Transport and supplementation did not appear to affect body weight, heart rate, IL-4, IL-8, IL-12α, IL-17α, change (Δ) in the % and mean fluorescence intensity (MFI) of IFNγ+ lymphocytes after stimulation, or Δ in the % and MFI of TNFα+ lymphocytes after stimulation. Supplementation decreased IL-1β and SAA1 expression. Transport increased total cortisol concentration, body temperature, and IL-2, IL-6, and IL-10 expression but decreased IL-1β, TNFα, and IFNγ expression. Short-term transportation affected physiological, endocrine, and immune responses; supplementation may ameliorate inflammation in aged horses. Immune responses were most altered at 15-min post-transport and typically recovered by Day 1, suggesting that horses may be vulnerable to disease during and almost immediately after short-term transport
Nanomechanical and thermophoretic analyses of the nucleotide-dependent interactions between the AAA+ subunits of magnesium chelatase
In chlorophyll biosynthesis, the magnesium
chelatase enzyme complex catalyzes the insertion of a Mg2+
ion into protoporphyrin IX. Prior to this event, two of the three
subunits, the AAA+ proteins ChlI and ChlD, form a ChlID−
MgATP complex. We used microscale thermophoresis to
directly determine dissociation constants for the I-D subunits
from Synechocystis, and to show that the formation of a ChlID−
MgADP complex, mediated by the arginine finger and the
sensor II domain on ChlD, is necessary for the assembly of the
catalytically active ChlHID−MgATP complex. The N-terminal
AAA+ domain of ChlD is essential for complex formation, but
some stability is preserved in the absence of the C-terminal
integrin domain of ChlD, particularly if the intervening polyproline linker region is retained. Single molecule force spectroscopy
(SMFS) was used to determine the factors that stabilize formation of the ChlID−MgADP complex at the single molecule level;
ChlD was attached to an atomic force microscope (AFM) probe in two different orientations, and the ChlI subunits were
tethered to a silica surface; the probability of subunits interacting more than doubled in the presence of MgADP, and we show
that the N-terminal AAA+ domain of ChlD mediates this process, in agreement with the microscale thermophoresis data. Analysis
of the unbinding data revealed a most probable interaction force of around 109 pN for formation of single ChlID−MgADP
complexes. These experiments provide a quantitative basis for understanding the assembly and function of the Mg chelatase
complex
Preliminary Assessment of and Lessons Learned in PITCH: an Integrated Approach to Developing Technical Communication Skills in Engineers
The Project to Integrate Technical Communication Habits (PITCH) has been implemented across seven engineering and computer science undergraduate programs starting in fall 2012. The overarching goal of PITCH is to develop written, oral and visual communication skills and professional habits in engineering students. PITCH activities begin in the very first semester and are reinforced and extended through all four years of each program. After three years of progressively more extensive development and deployment, a preliminary assessment of student writing over their first three years in programs was performed. In May 2016 the first cohort of students will have completed the entire sequence of PITCH courses, including senior design.
PITCH was designed to include technical memoranda, poster presentations, oral presentations, laboratory reports, proposals, and senior design reports. In addition to text elements, the use of tables and graphics also were addressed. These technical communication products are integrated into specific foundational courses common to several programs, as well as higher-level courses unique to each program. Engineering faculty teaching these courses were progressively trained through workshops conducted over three summers, so in the early years not all instructors teaching these courses had been fully trained. A random sample of students from four programs was selected for the assessment. These students had taken freshman through junior courses with trained instructors, and the assessment was performed based on the PITCH writing assignments they submitted in four courses.
Four faculty members and an external consultant involved in the development and deployment of PITCH performed the assessment. Each writing assignment was evaluated through use of a common rubric to see how well students achieved the overall PITCH learning outcomes. The evaluations were done in a series of collective settings with all five evaluators present and each writing assignment was assessed. Student progress through the four courses spanning the first three years of PITCH is quantified and the results are discussed.
Also discussed are pedagogical and administrative lessons learned during development and implementation of PITCH to date.
PITCH is supported by a grant from the Davis Educational Foundation
Capturing Debriefing and Enhancing Reflection within Simulated Clinical Learning Environments
This article presents findings from an evaluation of a new A3-size learner notes sheet designed for use by healthcare students engaging in clinical simulation and clinical skills sessions. The notes sheet consists of an adapted form of the SBAR (situation, background, assessment, response) tool, whilst capturing post-simulation oral debriefing provided by a facilitator. Additionally, the Driscoll (2007)model is used to provide students with an opportunity to reflect on their engagement in clinical simulation. Two cohorts of students, who engaged in separate simulation sessions, completed the A3 sheet. The study featured 33 midwifery and 21 operating department practitioner (ODP) students undertaking a simulation. Documentary analysis was undertaken to identify the depth of reflective writing of both groups of students. Midwifery student participants reflected on their experiences of simulation at a slightly deeper level than their ODP counterparts. All students adhered to the structure of the notes sheet when receiving their briefing from the facilitator and when asked to write their reflective accounts. This study has sought to explore an under-researched area of clinical simulation: the extent to which healthcare students can utilise reflection when engaging with a clinical scenario within a simulated learning environment
The genome sequence of Saccharomyces Eubayanus and the domestication of Lager-Brewing yeasts
The dramatic phenotypic changes that occur in organisms during domestication leave indelible imprints on their genomes. Although many domesticated plants and animals have been systematically compared with their wild genetic stocks, the molecular and genomic processes underlying fungal domestication have received less attention. Here, we present a nearly complete genome assembly for the recently described yeast species Saccharomyces eubayanus and compare it to the genomes of multiple domesticated alloploid hybrids of S. eubayanus × S. cerevisiae (S. pastorianus syn. S. carlsbergensis), which are used to brew lager-style beers. We find that the S. eubayanus subgenomes of lager-brewing yeasts have experienced increased rates of evolution since hybridization, and that certain genes involved in metabolism may have been particularly affected. Interestingly, the S. eubayanus subgenome underwent an especially strong shift in selection regimes, consistent with more extensive domestication of the S. cerevisiae parent prior to hybridization. In contrast to recent proposals that lager-brewing yeasts were domesticated following a single hybridization event, the radically different neutral site divergences between the subgenomes of the two major lager yeast lineages strongly favor at least two independent origins for the S. cerevisiae × S. eubayanus hybrids that brew lager beers. Our findings demonstrate how this industrially important hybrid has been domesticated along similar evolutionary trajectories on multiple occasions.Fil: Baker, Emily Clare. University Of Wisconsin; Estados UnidosFil: Wang, Bing. University Of Wisconsin; Estados UnidosFil: Bellora, Nicolás. Universidad Nacional del Comahue. Centro Regional Universidad de Bariloche. Departamento de Biologia. Laboratorio de Microbiologia Aplicada y Biotecnologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación en Biodiversidad y Medioambiente; ArgentinaFil: Peris, David. University Of Wisconsin; Estados UnidosFil: Hulfachor, Amanda Beth. University Of Wisconsin; Estados UnidosFil: Koshalek, Justin A.. University Of Wisconsin; Estados UnidosFil: Adams, Marie. University Of Wisconsin; Estados UnidosFil: Libkind Frati, Diego. Universidad Nacional del Comahue. Centro Regional Universidad de Bariloche. Departamento de Biologia. Laboratorio de Microbiologia Aplicada y Biotecnologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación en Biodiversidad y Medioambiente; ArgentinaFil: Hittinger, Chris Todd. University Of Wisconsin; Estados Unido
Structural and functional consequences of removing the N-terminal domain from the magnesium chelatase ChlH subunit of Thermosynechococcus elongatus
Magnesium chelatase (MgCH) initiates chlorophyll biosynthesis by catalysing the ATP-dependent insertion of Mg2+ into protoporphyrin. This large enzyme complex comprises ChlH, I and D subunits, with I and D involved in ATP hydrolysis, and H the protein that handles the substrate and product. The 148 kDa ChlH subunit has a globular N-terminal domain attached by a narrow linker to a hollow cage-like structure. Following deletion of this ~18 kDa domain from the Thermosynechoccus elongatus ChlH, we used single particle reconstruction to show that the apo- and porphyrin-bound forms of the mutant subunit consist of a hollow globular protein with three connected lobes; superposition of the mutant and native ChlH structures shows that, despite the clear absence of the N-terminal ‘head’ region, the rest of the protein appears to be correctly folded. Analyses of dissociation constants shows that the ΔN159ChlH mutant retains the ability to bind protoporphyrin and the Gun4 enhancer protein, although the addition of I and D subunits yields an extremely impaired active enzyme complex. Addition of the Gun4 enhancer protein, which stimulates MgCH activity significantly especially at low Mg2+ concentrations, partially reactivates the ΔN159ChlH–I–D mutant enzyme complex, suggesting that the binding site or sites for Gun4 on H do not wholly depend on the N-terminal domain
Brown Treesnake Mortality After Aerial Application of Toxic Baits
Quantitative evaluation of control tools for managing invasive species is necessary to assess overall effectiveness and individual variation in treatment susceptibility. Invasive brown treesnakes (Boiga irregularis) on Guam have caused severe ecological and economic effects, pose a risk of accidental introduction to other islands, and are the greatest impediment to the reestablishment of extirpated native fauna. An aerial delivery system for rodent‐based toxic baits can reduce brown treesnake abundance and heterogeneity among individuals may influence bait attraction or toxicant susceptibility. Previous baiting trials have either been simulated aerial treatments or relied on slightly different bait capsule compositions and the results of aerial delivery of toxic baits under operational conditions may not be directly comparable. We monitored 30 radio‐tagged adult snakes (990–1,265 mm snout‐vent length) during an aerial baiting operation in a 55‐ha area using transmitters equipped with accelerometers and receivers programed to display a status code indicating mortality if a snake failed to move for \u3e24 hours. We used known‐fate models to estimate mortality and evaluate a priori hypotheses explaining differences in mortality based on size, sex, and treatment effects. Eleven radio‐tagged snakes died in the aerial baiting treatment period (0.37, 95% CI=0.21–0.55) and no individuals (0.00, 95% CI=0.00–0.04) died during the non‐treatment period. Our data provide strong evidence for an additive size‐based treatment effect on mortality, with smaller adults (0.59, 95% CI=0.35–0.80) exhibiting higher mortality than larger snakes (0.14, 95% CI=0.02–0.37) but did not support a sex effect on mortality. The high mortality of snakes during the treatment period indicates that aerial baiting can reduce brown treesnake abundance, but further refinement or use in combination with other removal tools may be necessary to overcome size‐based differences in susceptibility and achieve eradication. © 2021 The Authors. The Journal of Wildlife Management published by Wiley Periodicals LLC on behalf of The Wildlife Society
Peer Reviewed Evaluation of Registered End-Points of Randomised Trials (the PRE-REPORT study): a stepped wedge, cluster-randomised trial.
OBJECTIVE: To test whether providing relevant clinical trial registry information to peer reviewers evaluating trial manuscripts decreases discrepancies between registered and published trial outcomes.
DESIGN: Stepped wedge, cluster-randomised trial, with clusters comprised of eligible manuscripts submitted to each participating journal between 1 November 2018 and 31 October 2019.
SETTING: Thirteen medical journals.
PARTICIPANTS: Manuscripts were eligible for inclusion if they were submitted to a participating journal during the study period, presented results from the primary analysis of a clinical trial, and were peer reviewed.
INTERVENTIONS: During the control phase, there were no changes to pre-existing peer review practices. After journals crossed over into the intervention phase, peer reviewers received a data sheet describing whether trials were registered, the initial registration and enrolment dates, and the registered primary outcome(s) when enrolment began.
MAIN OUTCOME MEASURE: The presence of a clearly defined, prospectively registered primary outcome consistent with the primary outcome in the published trial manuscript, as determined by two independent outcome assessors.
RESULTS: We included 419 manuscripts (243 control and 176 intervention). Participating journals published 43% of control-phase manuscripts and 39% of intervention-phase manuscripts (model-estimated percentage difference between intervention and control trials = -10%, 95% CI -25% to 4%). Among the 173 accepted trials, published primary outcomes were consistent with clearly defined, prospectively registered primary outcomes in 40 of 105 (38%) control-phase trials and 27 of 68 (40%) intervention-phase trials. A linear mixed model did not show evidence of a statistically significant primary outcome effect from the intervention (estimated difference between intervention and control=-6% (90% CI -27% to 15%); one-sided p value=0.68).
CONCLUSIONS: These results do not support use of the tested intervention as implemented here to increase agreement between prospectively registered and published trial outcomes. Other approaches are needed to improve the quality of outcome reporting of clinical trials.
TRIAL REGISTRATION NUMBER: ISRCTN41225307
BioTIME: A Database of Biodiversity Time Series for the Anthropocene
Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene. Main types of variables included: The database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record. Spatial location and grain: BioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km(2) (158 cm(2)) to 100 km(2) (1,000,000,000,000 cm(2)). Time period and grainBio: TIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year. Major taxa and level of measurement: BioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates
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