173 research outputs found

    Versatile Apparatus for Measuring Kinetics of Gaseous Reactions by a Relative Method

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    It is important that accurate, reproducible values for the rates of chemical reactions occurring in the atmosphere be obtained. The value of accurate kinetics measurements is to improve the accuracy of mathematical models used to forecast the state of the atmosphere. We describe a versatile, robust apparatus for obtaining atmospheric reaction rate values and their temperature dependencies by a relative method. This relative method has the advantage over absolute methods in that errors due to impurities and adsorption on walls of the reaction apparatus are minimized. In addition, relative values serve as an important verification for absolute values. The apparatus serves to mix sample and reference gases, used in the studies, with helium, water vapor and oxygen and deliver them to a quartz reaction cell whose temperature can be controlled between of -50 C and +350 C. Reaction is carried out by use of a low pressure mercury vapor lamp radiating the sample for different periods of time. The mercury lamp produces hydroxyl radicals in the presence of the water vapor in the reaction mixture. The hydroxyl radicals abstract hydrogen atoms from the sample molecules. Oxygen is needed to mimic reaction conditions in the atmosphere which is rich in oxygen. Measurement of the concentrations of unreacted and reacted mixtures are obtained by injecting these samples into a gas chromatograph having a mass spectrometer detector, GC/MS. Analysis of the rates of reaction of cyclopropane and difluoromethoxydifluoromethane, CHF2OCHF2, (HFOC-134) with hydroxyl radicals yields the following results: For cyclopropane, a rate of 7.85x10-14:s-1 at 298.15 Kand an activation energy, E/R, of 1323 was obtained. For HFOC-134, a rate of 2.23x10-15 s-1 at 298.15 Kand an activation energy, E/R, of 1895 was obtained

    Toward System Change to Tackle Antimicrobial Resistance: Improving the Voluntary Stewardship of Antimicrobials in US Agriculture

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    From Executive Summary:This report presents the details of a research study looking at the potential for improving voluntary stewardship of antimicrobials in US agriculture, in the interests of tackling antimicrobial resistance (AMR). Failure to address AMR could lead to significant impacts on both human and animal health. Voluntary stewardship is an approach that relies on the willingness of food-animal producers and supportive industries (e.g., veterinary services and pharmaceutical companies), as well as broader stakeholders (e.g., public health policymakers and consumer advocates), to ensure the judicious use of antimicrobials without the need for regulation, legislation, mandatory compliance or statutory enforcement

    Impending Regeneration Failure of the IUCN Vulnerable Borneo Ironwood (Eusideroxylon zwageri)

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    The regeneration of many climax species in tropical forest critically depends on adequate seed dispersal and seedling establishment. Here, we report the decreased abundance and increased spatial aggregation of younger trees of the Borneo ironwood (Eusideroxylon zwageri) in a protected forest in Sabah Malaysia. We observed a high level of seedling herbivory with strong density dependence, likely exacerbated by local aggregation and contributing to the progressively shrinking size distribution. We also note the largely undocumented selective herbivory by sambar deer on E. zwageri seedlings. This study highlights the combined impact of altered megafauna community on a tree population through interlinked ecological processes and the need for targeted conservation intervention for this iconic tropical tree species

    The E3 ubiquitin ligase component, Cereblon, is an evolutionarily conserved regulator of Wnt signaling

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    Immunomodulatory drugs (IMiDs) are important for the treatment of multiple myeloma and myelodysplastic syndrome. Binding of IMiDs to Cereblon (CRBN), the substrate receptor of the CRL4CRBN E3 ubiquitin ligase, induces cancer cell death by targeting key neo-substrates for degradation. Despite this clinical significance, the physiological regulation of CRBN remains largely unknown. Herein we demonstrate that Wnt, the extracellular ligand of an essential signal transduction pathway, promotes the CRBN-dependent degradation of a subset of proteins. These substrates include Casein kinase 1α (CK1α), a negative regulator of Wnt signaling that functions as a key component of the β-Catenin destruction complex. Wnt stimulation induces the interaction of CRBN with CK1α and its resultant ubiquitination, and in contrast with previous reports does so in the absence of an IMiD. Mechanistically, the destruction complex is critical in maintaining CK1α stability in the absence of Wnt, and in recruiting CRBN to target CK1α for degradation in response to Wnt. CRBN is required for physiological Wnt signaling, as modulation of CRBN in zebrafish and Drosophila yields Wnt-driven phenotypes. These studies demonstrate an IMiD-independent, Wnt-driven mechanism of CRBN regulation and provide a means of controlling Wnt pathway activity by CRBN, with relevance for development and disease

    Measuring the health-related Sustainable Development Goals in 188 countries : a baseline analysis from the Global Burden of Disease Study 2015

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    Background In September, 2015, the UN General Assembly established the Sustainable Development Goals (SDGs). The SDGs specify 17 universal goals, 169 targets, and 230 indicators leading up to 2030. We provide an analysis of 33 health-related SDG indicators based on the Global Burden of Diseases, Injuries, and Risk Factors Study 2015 (GBD 2015). Methods We applied statistical methods to systematically compiled data to estimate the performance of 33 health-related SDG indicators for 188 countries from 1990 to 2015. We rescaled each indicator on a scale from 0 (worst observed value between 1990 and 2015) to 100 (best observed). Indices representing all 33 health-related SDG indicators (health-related SDG index), health-related SDG indicators included in the Millennium Development Goals (MDG index), and health-related indicators not included in the MDGs (non-MDG index) were computed as the geometric mean of the rescaled indicators by SDG target. We used spline regressions to examine the relations between the Socio-demographic Index (SDI, a summary measure based on average income per person, educational attainment, and total fertility rate) and each of the health-related SDG indicators and indices. Findings In 2015, the median health-related SDG index was 59.3 (95% uncertainty interval 56.8-61.8) and varied widely by country, ranging from 85.5 (84.2-86.5) in Iceland to 20.4 (15.4-24.9) in Central African Republic. SDI was a good predictor of the health-related SDG index (r(2) = 0.88) and the MDG index (r(2) = 0.2), whereas the non-MDG index had a weaker relation with SDI (r(2) = 0.79). Between 2000 and 2015, the health-related SDG index improved by a median of 7.9 (IQR 5.0-10.4), and gains on the MDG index (a median change of 10.0 [6.7-13.1]) exceeded that of the non-MDG index (a median change of 5.5 [2.1-8.9]). Since 2000, pronounced progress occurred for indicators such as met need with modern contraception, under-5 mortality, and neonatal mortality, as well as the indicator for universal health coverage tracer interventions. Moderate improvements were found for indicators such as HIV and tuberculosis incidence, minimal changes for hepatitis B incidence took place, and childhood overweight considerably worsened. Interpretation GBD provides an independent, comparable avenue for monitoring progress towards the health-related SDGs. Our analysis not only highlights the importance of income, education, and fertility as drivers of health improvement but also emphasises that investments in these areas alone will not be sufficient. Although considerable progress on the health-related MDG indicators has been made, these gains will need to be sustained and, in many cases, accelerated to achieve the ambitious SDG targets. The minimal improvement in or worsening of health-related indicators beyond the MDGs highlight the need for additional resources to effectively address the expanded scope of the health-related SDGs.Peer reviewe

    How can BCO-DMO help with your oceanographic data?

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    Presented at Fall AGU (ESIP Data Helpdesk), New Orleans, 11-17, December 2021BCO-DMO curates a database of research-ready data spanning the full range of marine ecosystem related measurements including in-situ and remotely sensed observations, experimental and model results, and synthesis products. We work closely with investigators to publish data and information from research projects supported by the National Science Foundation (NSF), as well as those supported by state, private, and other funding sources. BCO-DMO supports all phases of the data life cycle and ensures open access of well-curated project data and information. We employ F.A.I.R. Principles that comprise a set of values intended to guide data producers and publishers in establishing good data management practices that will enable effective reuse.Award(s): NSF #192461

    Biological and Chemical Oceanography Data Management Office: Supporting a New Vision for Adaptive Management of Oceanographic Data [poster]

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    Presented at 2022 OCB Summer Workshop, Woods Hole, MA, 20 - 23, June 2022An unparalleled data catalog of well-documented, interoperable oceanographic data and information, openly accessible to all end-users through an intuitive web-based interface for the purposes of advancing marine research, education, and policy. Conference Website: https://web.whoi.edu/ocb-workshop/NSF #192461
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