678 research outputs found

    Mentorship Matters

    Get PDF
    The researchers have identified the creation of a successful farming cooperative as a goal for the Pembroke Farming Family Association (PFFA), and have examined the literature to determine the components of such cooperatives. A literature review revealed that increased education in many areas is strongly correlated with successful farming cooperatives. The researchers determined that education through mentorship is an evidence based practice which could be implemented as an intervention. Then, the researchers located the measurement instrument of seasonal pre-test and post-test surveys, which would require additional questions related to specifics of farming in Pembroke. Finally, the researchers found that dependent t-tests could be used to analyze the data gathered through the measurement instruments. After evaluating the study for validity and reliability, the researchers believe that the proposal will effectively examine the possibility of the implementation of mentorship programs to assist the creation of a successful farming cooperative in Pembroke. During this session, participants will Learn of the varied needs in the Pembroke Township Understand literature results which identify barriers to community development in rural, impoverished communities Discover opportunities for community development in the Pembroke community Explore the proposed mentorship structure to decrease barriers to employment and increase life skills developmen

    Mentorship Matters

    Get PDF
    The researchers have identified the creation of a successful farming cooperative as a goal for the Pembroke Farming Family Association (PFFA), and have examined the literature to determine the components of such cooperatives. A literature review revealed that increased education in many areas is strongly correlated with successful farming cooperatives. The researchers determined that education through mentorship is an evidence based practice which could be implemented as an intervention. Then, the researchers located the measurement instrument of seasonal pre-test and post-test surveys, which would require additional questions related to specifics of farming in Pembroke. Finally, the researchers found that dependent t-tests could be used to analyze the data gathered through the measurement instruments. After evaluating the study for validity and reliability, the researchers believe that the proposal will effectively examine the possibility of the implementation of mentorship programs to assist the creation of a successful farming cooperative in Pembroke. During this session, participants will Learn of the varied needs in the Pembroke Township Understand literature results which identify barriers to community development in rural, impoverished communities Discover opportunities for community development in the Pembroke community Explore the proposed mentorship structure to decrease barriers to employment and increase life skills developmen

    Ractopamine HCl improved cardiac hypertrophy but not poor growth, metabolic inefficiency, or greater white blood cells associated with heat stress in concentrate-fed lambs

    Get PDF
    Heat stress decreases livestock performance and well-being (Hahn, 1999; Nienaber and Hahn, 2007), causes metabolic dysfunction that decreases growth efficiency (O’Brien et al., 2010), and alters cardiovascular function (Crandall et al., 2008). Each year, heat stress costs the livestock industry up to $2.5 billion (St-Pierre et al., 2003). Ractopamine HCl acts as a nutrient repartitioning agent (Beermann, 2002); classified as a β adrenergic agonist (βAA), it shares pharmacological properties with adrenaline (Beermann, 2002). βAA increase muscle mass and decreases fat deposition through unknown mechanisms (Beermann, 2002). In feedlot cattle, they increase growth efficiency and improve carcass yield and merit (Scramlin et al., 2010; Buntyn et al., 2017), which increases profit and allows more meat to be produced from fewer animals. However, because βAA act via a stress system, it is unclear how the products affect animals under stress conditions. β1AA and β2AA can also cause tachycardia, heart palpitations, and arrhythmias (Sears, 2002). We hypothesize that β1AA combined with heat stress may overstimulate the adrenergic system, resulting is metabolic dysfunction and decreased performance. Sheep are a common model for cattle, and thus, the objective of this study was to determine the impact of ractopamine HCl on health and cardiovascular parameters, growth, and metabolic efficiency in feeder lambs

    Computer simulation of water in cytochrome c oxidase

    Get PDF
    AbstractStatistical mechanics and molecular dynamics simulations have been carried out to study the distribution and dynamics of internal water molecules in bovine heart cytochrome c oxidase (CcO). CcO is found to be capable of holding plenty of water, which in subunit I alone amounts to about 165 molecules. The dynamic characterization of these water molecules is carried out. The nascent water molecules produced in the redox reaction at the heme a3–CuB binuclear site form an intriguing chain structure. The chain begins at the position of Glu242 at the end of the D channel, and has a fork structure, one branch of which leads to the binuclear center, and the other to the propionate d of heme a3. The branch that leads to the binuclear center has dynamic access both to the site where the formation of water occurs, and to delta-nitrogen of His291. From the binuclear center, the chain continues to run into the K channel. The stability of this hydrogen bond network is examined dynamically. The catalytic site is located at the hydrophobic region, and the nascent water molecules are produced at the top of the energy hill. The energy gradient is utilized as the mechanism of water removal from the protein. The water exit channels are explored using high-temperature dynamics simulations. Two putative channels for water exit from the catalytic site have been identified. One is leading directly toward Mg2+ site. However, this channel is only open when His291 is dissociated from CuB. If His291 is bound to CuB, the only channel for water exit is the one that originates at E242 and leads toward the middle of the membrane. This is the same channel that is presumably used for oxygen supply

    Promotion permutations for tableaux

    Full text link
    In our companion paper, we develop a new SL4SL_4-web basis. Basis elements are given by certain planar graphs and are constructed so that important algebraic operations can be performed diagrammatically. A guiding principle behind our construction is that the long cycle (12…n)∈Sn(12\ldots n) \in \mathfrak{S}_n should act by rotation of webs. Moreover, the bijection between webs and tableaux should intertwine rotation with the promotion action on tableaux. In this paper, we develop necessary notions of promotion permutations and promotion matrices, which are new even for standard tableaux. To support inductive arguments in the companion paper, we must however work in the more general setting of fluctuating tableaux, which we introduce and which subsumes many classes of tableaux that have been previously studied, including (generalized) oscillating, vacillating, rational, alternating, and (semi)standard tableaux. Therefore, we also give here a full development of the basic combinatorics and representation theory of fluctuating tableaux.Comment: 42 pages, 8 figure

    Body composition estimated by bioelectrical impedance analyses is diminished by prenatal stress in neonatal lambs and by heat stress in feedlot wethers

    Get PDF
    Body composition correlates to carcass value in livestock, which makes the ability to accurately estimate body composition in the live animal beneficial (Berg and Marchello, 1994). Bioelectrical impedance analysis (BIA) is a clinical tool used to assess body composition in humans (Lukaski et al., 1985), but its use in livestock has been minimal. Lean and fat content contribute to profitability for livestock producers, and poor body composition can be caused by stress that occurs either during in utero development (De Blasio et al., 2007) or during postnatal growth (Boyd et al., 2015). Maternal hyperthermia-induced placental insufficiency (Brown et al., 2015) and sustained maternal inflammation (Cadaret et al., 2018) are two established causes of intrauterine growth restriction (IUGR). IUGR-born animals are characterized by asymmetrical growth restriction that alters lifelong body composition due to impaired muscle growth capacity (Yates et al., 2018). In addition, acute heat stress during periods of peak postnatal growth can alter body composition in livestock (Boyd et al., 2015). We postulate that BIA can detect these changes in the live animal. Thus, the objective of this study was to determine whether BIA measurements can predict changes to body composition in live neonatal lambs exposed to intrauterine stress and in heat-stressed feedlot lambs

    Maternal inflammation at 0.7 gestation in ewes leads to intrauterine growth restriction and impaired glucose metabolism in offspring at 30 d of age

    Get PDF
    Fetal programming associated with intrauterine growth restriction (IUGR) leads to lifelong deficits in growth and metabolic function (Hales and Barker, 2013). IUGR arises when fetuses respond to poor in utero conditions by developing adaptations that repartition nutrients to critical tissues and away from skeletal muscle (Yates et al., 2012, 2018). This fetal programming is beneficial in utero but leads to persistent reductions in muscle mass and glucose homeostasis in offspring (DeFronzo et al., 1981). Recent studies by our laboratory in sheep and rats demonstrate that maternal inflammation during gestation induces fetal inflammatory adaptations that impair growth and disrupt muscle glucose metabolism (Cadaret et al., 2017, 2018). IUGR fetal skeletal muscle exhibits indicators of enhanced inflammatory sensitivity, which could disrupt glucose uptake and oxidation (Yates et al., 2016; Cadaret et al., 2018). Enhanced inflammatory responsiveness would help explain growth and metabolic deficits observed in IUGR offspring. We hypothesize that fetal programming induced by maternal inflammation persists in offspring and contributes to impaired growth and glucose metabolism at 30 d. Therefore, the objective of this study was to determine whether sustained maternal inflammation induced by bacterial endotoxin at 0.7 gestation leads to fetal programming that contributes to deficits in growth and glucose metabolism in offspring

    Developing a health sciences information literacy assessment for undergraduates.

    Get PDF
    This poster describes the development and pilot of a tailored information literacy assessment tool for undergraduate allied health students. Tool development included collaboration between assessment experts, Health Science faculty, and Health Science librarians. The poster includes results from the tool deployment and next steps in applying results back into revised curriculum

    Considering Questions Before Methods in Dementia Research With Competing Events and Causal Goals

    Get PDF
    Studying causal exposure effects on dementia is challenging when death is a competing event. Researchers often interpret death as a potential source of bias, although bias cannot be defined or assessed if the causal question is not explicitly specified. Here we discuss 2 possible notions of a causal effect on dementia risk: the “controlled direct effect” and the “total effect.” We provide definitions and discuss the “censoring” assumptions needed for identification in either case and their link to familiar statistical methods. We illustrate concepts in a hypothetical randomized trial on smoking cessation in late midlife, and emulate such a trial using observational data from the Rotterdam Study, the Netherlands, 1990–2015. We estimated a total effect of smoking cessation (compared with continued smoking) on 20-year dementia risk of 2.1 (95% confidence interval: −0.1, 4.2) percentage points and a controlled direct effect of smoking cessation on 20-year dementia risk had death been prevented of −2.7 (95% confidence interval: −6.1, 0.8) percentage points. Our study highlights how analyses corresponding to different causal questions can have different results, here with point estimates on opposite sides of the null. Having a clear causal question in view of the competing event and transparent and explicit assumptions are essential to interpreting results and potential bias.</p

    Acid activation mechanism of the influenza A M2 proton channel

    Get PDF
    The homotetrameric influenza A M2 channel (AM2) is an acid-activated proton channel responsible for the acidification of the influenza virus interior, an important step in the viral lifecycle. Four histidine residues (His37) in the center of the channel act as a pH sensor and proton selectivity filter. Despite intense study, the pH-dependent activation mechanism of the AM2 channel has to date not been completely understood at a molecular level. Herein we have used multiscale computer simulations to characterize (with explicit proton transport free energy profiles and their associated calculated conductances) the activation mechanism of AM2. All proton transfer steps involved in proton diffusion through the channel, including the protonation/deprotonation of His37, are explicitly considered using classical, quantum, and reactive molecular dynamics methods. The asymmetry of the proton transport free energy profile under high-pH conditions qualitatively explains the rectification behavior of AM2 (i.e., why the inward proton flux is allowed when the pH is low in viral exterior and high in viral interior, but outward proton flux is prohibited when the pH gradient is reversed). Also, in agreement with electrophysiological results, our simulations indicate that the C-terminal amphipathic helix does not significantly change the proton conduction mechanism in the AM2 transmembrane domain; the four transmembrane helices flanking the channel lumen alone seem to determine the proton conduction mechanism.United States. National Institutes of Health (R01-GM088204
    • …
    corecore