1,577 research outputs found

    Biomimicry of Volatile-Based Microbial Control for Mitigating Fungal Pathogenicity

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    Volatile organic compounds (VOCs) are organic chemicals typically characterized as having low molecular weight, low solubility in water, and high vapor pressure. Consequently, they readily evaporate from liquid to the gaseous phase at standard temperature and pressure. VOCs are produced by many microorganisms as a result of both uninduced and induced metabolic pathways. Volatile-based microbial inhibition in environments such as soil is well founded, with numerous antimicrobial VOCs and formulations having been identified. Inhibitory VOCs are of particular interest as microbial control agents, as low concentrations of gaseous VOCs have been observed to elicit significant antimicrobial effects. It is believed that this contact-independent antagonism may present unique advantages over traditional microbial control methods, particularly where contact-dependent treatment methods are either impractical or inconvenient. This method may be of particular benefit for managing infections where disease may become pervasive in the population, such as with white-nose syndrome (WNS) among bats. A list of potential antifungal compounds and formulations was compiled by referencing the scientific literature. Screening of compounds and formulations was conducted through toxicity analyses and antimicrobial susceptibility testing for the in vitro ability of VOCs and formulations to inhibit growth of select pathogenic fungi. A dispersal system was developed that entailed electrical circuit and software engineering as well as quantitative analysis to validate consistent and accurate dispersal of potential treatment compounds and formulations. Successful completion of these goals culminated in exposure trials involving live bats to determine any significant toxicological effects. Ex and in situ treatment trials were conducted to determine efficacy of promoting the reduction of disease severity and increasing survivorship of infected bat populations. The identification of volatile-based inhibitory compounds, in conjunction with a novel method for accurate and automated delivery, could prove a promising treatment and prophylactic in combatting microbial pathogenesis and contamination

    A preliminary report on the contact-independent antagonism of Pseudogymnoascus destructans by Rhodococcus rhodochrous strain DAP96253.

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    BackgroundThe recently-identified causative agent of White-Nose Syndrome (WNS), Pseudogymnoascus destructans, has been responsible for the mortality of an estimated 5.5 million North American bats since its emergence in 2006. A primary focus of the National Response Plan, established by multiple state, federal and tribal agencies in 2011, was the identification of biological control options for WNS. In an effort to identify potential biological control options for WNS, multiply induced cells of Rhodococcus rhodochrous strain DAP96253 was screened for anti-P. destructans activity.ResultsConidia and mycelial plugs of P. destructans were exposed to induced R. rhodochrous in a closed air-space at 15°C, 7°C and 4°C and were evaluated for contact-independent inhibition of conidia germination and mycelial extension with positive results. Additionally, in situ application methods for induced R. rhodochrous, such as fixed-cell catalyst and fermentation cell-paste in non-growth conditions, were screened with positive results. R. rhodochrous was assayed for ex vivo activity via exposure to bat tissue explants inoculated with P. destructans conidia. Induced R. rhodochrous completely inhibited growth from conidia at 15°C and had a strong fungistatic effect at 4°C. Induced R. rhodochrous inhibited P. destructans growth from conidia when cultured in a shared air-space with bat tissue explants inoculated with P. destructans conidia.ConclusionThe identification of inducible biological agents with contact-independent anti- P. destructans activity is a major milestone in the development of viable biological control options for in situ application and provides the first example of contact-independent antagonism of this devastating wildlife pathogen

    Computational Naval Ship Hydrodynamics

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    The primary purpose of our research efforts is to improve naval design and detection capabilities. Our current research efforts leverage high performance computing (HPC) resources to perform high-resolution numerical simulations with hundreds-of-millions to billions of unknowns to study wave breaking behind a transom stern, wave-impact loading, the generation of spray by high-speed planing craft, air entrainment by plunging breaking waves, forced-motion, and storm seas. This paper focuses on the air entrainment and free-surface turbulence in the flow behind a transom-stern and wave-impact loading on marine platforms. Two codes, Numerical Flow Analysis (NFA) and Boundary Data Immersion Method (BDIM), are used in this study. Both codes are Cartesian-based Large-Eddy Simulation (LES) formulations, and use either Volume-of-Fluid (VOF) (NFA) or conservative Volume-of-Fluid (cVOF) BDIM treatments to track the free-surface interface. The first project area discussed is the flow behind the transom stern. BDIM simulations are used to study the volume of entrained air behind the stern. The application of a Lagrangian bubble-extraction algorithm elucidates the location of air cavities in the wake and the bubble-size distribution for a flow that has over 10 percent void fraction. NFA simulations of the transom-stern flow are validated by comparing the numerical simulations to experiments performed at the Naval Surface Warfare Center, Carderock Division (NSWCCD), where good agreement between simulations and experiments is obtained for mean elevations and regions of white water in the wake. The second project area discussed is wave impact loading, a topic driven by recent structural failures of high-speed planing vessels and other advanced vehicles, as well as the devastation caused by Tsunamis impacting low-lying coastal areas. NFA simulations of wave breaking events are compared to the NSWCCD cube impact experiments and the Oregon State University, O.H. Hinsdale Wave Research Laboratories Tsunami experiments, and it is shown that NFA is able to accurately simulate the propagation of waves over long distances after which it also accurately predicts highly-energetic impact events. © 2011 IEEE.United States. Office of Naval Research (N00014-07-C-0184)United States. Office of Naval Research (N00014-01-1-0124

    Bibliometric and authorship trends over a 30 year publication history in two representative US sports medicine journals

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    Bibliometric studies are important to understand changes and improvement opportunities in academia. This study compared bibliometric trends for two major sports medicine/arthroscopy journals, the American Journal of Sports MedicineÂź (AJSMÂź) and ArthroscopyÂź over the past 30 years. Trends over time and comparisons between both journals were noted for common bibliometric variables (number of authors, references, pages, citations, and corresponding author position) as well as author gender and continental origin. Appropriate statistical analyses were performed. A p < 0.001 was considered statistically significant. One representative year per decade was used. There were 814 manuscripts from AJSMÂź and 650 from ArthroscopyÂź. For AJSMÂź the number of manuscripts steadily increased from 86 in 1986 to 350 in 2016; for ArthroscopyÂź the number of manuscripts increased from 73 in 1985/1986, to 267 in 2006, but then dropped to 229 in 2016. There were significant increases in all bibliometric variables, except for the number of citations which decreased in ArthroscopyÂź. There were significant differences in manuscript region of origin by journal (p = 0.000002). ArthroscopyÂź had a greater percentage of manuscripts from Asia than AJSMÂź (19.3% vs 11.5%) while AJSMÂź had a greater percentage from North America (70.3% vs 59.2%); both journals had similar percentages from Europe (18.2% for AJSMÂź and 21.6% for ArthroscopyÂź). For AJSMÂź the average percentage of female first authors was 13.3%, increasing from 4.7% in 1986 to 19.3% in 2016; the average percentage of female corresponding authors was 7.3%. For ArthroscopyÂź, the average percentage of female first authors was 8.1%, increasing from 2.8% in 1985/1986 to 15.7% in 2016 (p = 0.00007). In conclusion, AJSMÂź and ArthroscopyÂź showed an increase in most variables analyzed. Although ArthroscopyÂź is climbing at a higher rate than AJSMÂź for female authors, AJSMÂź has an overall greater percentage of female authors

    The correct prednisone starting dose in polymyalgia rheumatica is related to body weight but not to disease severity

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    <p>Abstract</p> <p>Background</p> <p>the mainstay of treatment of polymyalgia rheumatica (PMR) is oral glucocorticoids, but randomized controlled trials of treatment are lacking. As a result, there is no evidence from controlled studies on the efficacy of different initial doses or glucocorticoid tapering. The aim of this study is to test if 12.5 mg prednisone/day is an adequate starting dose in PMR and to evaluate clinical predictors of drug response.</p> <p>Methods</p> <p>60 consecutive PMR patients were treated with a starting dose of 12,5 mg/day prednisone. Clinical, laboratory, and, in a subset of 25 patients, ultrasonographic features were recorded as possible predictors of response to prednisone. Remission was defined as disappearance of at least 75% of the signs and symptoms of PMR and normalization of ESR and CRP within the first month, a scenario allowing steroid tapering.</p> <p>Results</p> <p>47/60 (78.3%) patients responded to 12.5 mg of prednisone after a mean interval of 6.6 ± 5.2 days. In univariate analysis, body weight and gender discriminated the two groups. In multivariate analysis, the only factor predicting a good response was low weight (p = 0.004); the higher response rate observed in women was explained by their lower weight. The mean prednisone dose per kg in the responders was 0.19 ± 0.03 mg in comparison with 0.16 ± 0.03 mg for non responders (p = 0.007).</p> <p>Conclusions</p> <p>12.5 mg prednisone is a sufficient starting dose in Ÿ of PMR patients. The main factor driving response to prednisone in PMR was weight, a finding that could help in the clinical care of PMR patients and in designing prospective studies of treatment.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT01169597">NCT01169597</a></p

    Utilization of Daucus carota subsp. Sativus (Carrot) Peels and Oryza sativa (Rice) as Alternative Materials for Paper Production

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    The problem of pollution and deforestation have continuously contributed to the mass deterioration of the environment. This study aimed to create paper from rice and carrot wastes tested in a laboratory. The study followed an experimental research design, utilizing TAPPI T-220 test methods and ISO standard procedures. The paper sheets were tested under four quality tests: paper tear index, folding endurance, grammage, and paper burst strength. Data gathered from laboratory tests were statistically analyzed via the independent t-test. It was found that rice papers had a higher paper tear index (4.99 mN.m^2/g), folding endurance (3.81 folds), and paper burst strength (1.47 kPa.m^2/g) than carrot papers (2.56 mN.m^2/g, 0.77, and 1.10 kPa.m^2/g). Carrot papers, however, had higher grammage than rice papers (152.76 g/m^2 and 132.90 g/m^2, respectively). There was no significant difference found in data for paper tear index (p = 0.072) and paper burst strength (p = 0.13), while there was a substantial difference in terms of folding endurance (p = 0.033). Previous studies have supported each result and findings. In conclusion, cooked rice can be considered a promising raw material for the paper industry. Although carrot papers were significantly weaker, they still provided average values compared to normal papers. Future research should consider exploring other interventions such as soda pulping and kraft pulpin

    Water-Use Data in the United States: Challenges and Future Directions

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    In the United States, greater attention has been given to developing water supplies and quantifying available waters than determining who uses water, how much they withdraw and consume, and how and where water use occurs. As water supplies are stressed due to an increasingly variable climate, changing land-use, and growing water needs, greater consideration of the demand side of the water balance equation is essential. Data about the spatial and temporal aspects of water use for different purposes are now critical to long-term water supply planning and resource management. We detail the current state of water-use data, the major stakeholders involved in their collection and applications, and the challenges in obtaining high-quality nationally consistent data applicable to a range of scales and purposes. Opportunities to improve access, use, and sharing of water-use data are outlined. We cast a vision for a world-class national water-use data product that is accessible, timely, and spatially detailed. Our vision will leverage the strengths of existing local, state, and federal agencies to facilitate rapid and informed decision-making, modeling, and science for water resources. To inform future decision-making regarding water supplies and uses, we must coordinate efforts to substantially improve our capacity to collect, model, and disseminate water-use data

    Non-Compliance with Growth Hormone Treatment in Children Is Common and Impairs Linear Growth

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    BACKGROUND: GH therapy requires daily injections over many years and compliance can be difficult to sustain. As growth hormone (GH) is expensive, non-compliance is likely to lead to suboptimal growth, at considerable cost. Thus, we aimed to assess the compliance rate of children and adolescents with GH treatment in New Zealand. METHODS: This was a national survey of GH compliance, in which all children receiving government-funded GH for a four-month interval were included. Compliance was defined as ≄ 85% adherence (no more than one missed dose a week on average) to prescribed treatment. Compliance was determined based on two parameters: either the number of GH vials requested (GHreq) by the family or the number of empty GH vials returned (GHret). Data are presented as mean ± SEM. FINDINGS: 177 patients were receiving GH in the study period, aged 12.1 ± 0.6 years. The rate of returned vials, but not number of vials requested, was positively associated with HVSDS (p < 0.05), such that patients with good compliance had significantly greater linear growth over the study period (p<0.05). GHret was therefore used for subsequent analyses. 66% of patients were non-compliant, and this outcome was not affected by sex, age or clinical diagnosis. However, Maori ethnicity was associated with a lower rate of compliance. INTERPRETATION: An objective assessment of compliance such as returned vials is much more reliable than compliance based on parental or patient based information. Non-compliance with GH treatment is common, and associated with reduced linear growth. Non-compliance should be considered in all patients with apparently suboptimal response to GH treatment

    Mechanisms for the Intracellular Manipulation of Organelles by Conventional Electroporation

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    Conventional electroporation (EP) changes both the conductance and molecular permeability of the plasma membrane (PM) of cells and is a standard method for delivering both biologically active and probe molecules of a wide range of sizes into cells. However, the underlying mechanisms at the molecular and cellular levels remain controversial. Here we introduce a mathematical cell model that contains representative organelles (nucleus, endoplasmic reticulum, mitochondria) and includes a dynamic EP model, which describes formation, expansion, contraction, and destruction for the plasma and all organelle membranes. We show that conventional EP provides transient electrical pathways into the cell, sufficient to create significant intracellular fields. This emerging intracellular electrical field is a secondary effect due to EP and can cause transmembrane voltages at the organelles, which are large enough and long enough to gate organelle channels, and even sufficient, at some field strengths, for the poration of organelle membranes. This suggests an alternative to nanosecond pulsed electric fields for intracellular manipulations.National Science Foundation (U.S.) (NSF Graduate Research Fellowship)National Institutes of Health (U.S.) (grant No. R01-GM63857)Aegis Industries, Inc

    The state of the Martian climate

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    60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes
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