6,616 research outputs found

    Half-life of the electron-capture decay of 97Ru: Precision measurement shows no temperature dependence

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    We have measured the half-life of the electron-capture (ec) decay of 97Ru in a metallic environment, both at low temperature (19K), and also at room temperature. We find the half-lives at both temperatures to be the same within 0.1%. This demonstrates that a recent claim that the ec decay half-life for 7Be changes by $0.9% +/- 0.2% under similar circumstances certainly cannot be generalized to other ec decays. Our results for the half-life of 97Ru, 2.8370(14)d at room temperature and 2.8382(14)d at 19K, are consistent with, but much more precise than, previous room-temperature measurements. In addition, we have also measured the half-lives of the beta-emitters 103Ru and 105Rh at both temperatures, and found them also to be unchanged.Comment: 6 pages, 6 figure

    Conventional clear-sky aerosol retrievals: Do they work for cloudy days?

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    This presentation highlights different approaches to determine the aerosol properties between clouds and covers a broad range of related topics, including the passive aerosol remote sensing from space, in situ observations of aerosol aloft and at surface and numerical modeling of aerosol and cloud properties. Some of these approaches, which are still in research phase, can reduce substantially the impact of cloud-induced contamination on the cloudy-sky aerosol retrievals, while other can reduce uncertainties associated with aerosol hygroscopicity and enhanced relative humidity near cloud edges. The combination of these approaches for addressing outstanding issues of the cloudy-sky aerosol retrievals is also discussed

    The impacts of a nature-based mentorship program on students’ self-regulation: Harnessing the anticipation effect

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    Self-regulation is essential to youths’ long-term mental well-being and healthy functioning and positive anticipation of future events may support healthy emotional regulation. Green Chimneys, a school in New York that serves students with special education needs and psychosocial challenges, offers its students weekly one-on-one nature-based mentoring sessions with school staff. We used a modified version of the State Difficulties in Emotion Regulation Scale (S-DERS) to explore how these sessions impacted students’ emotional regulation both before and after their sessions. Results indicated that students’ behavior may improve in the 1-4 hours prior to participation. Further research is needed to test these findings

    The relevance of aerosol optical depth to cumulus fraction changes: a five-year climatology at the ACRF SGP site

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    International audienceThe objective of this study is to investigate, by observational means, the magnitude and sign of the actively discussed relationship between cloud fraction N and aerosol optical depth ?a. Collocated and coincident ground-based measurements and Terra/Aqua satellite observations at the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) Southern Great Plains (SGP) site form the basis of this study. The N??a relationship occurred in a specific 5-year dataset of fair-weather cumulus (FWC) clouds and mostly non-absorbing aerosols. To reduce possible contamination of the aerosols on the cloud properties estimation (and vice versa), we use independent datasets of ?a and N obtained from the Multi-filter Rotating Shadowband Radiometer (MFRSR) measurements and from the ARM Active Remotely Sensed Clouds Locations (ARSCL) value-added product, respectively. Optical depth of the FWC clouds ?cld and effective radius of cloud droplets re are obtained from the MODerate resolution Imaging Spectroradiometer (MODIS) data. We found that relationships between cloud properties (N,?cld, re) and aerosol optical depth are time-dependent (morning versus afternoon). Observed time-dependent changes of cloud properties, associated with aerosol loading, control the variability of surface radiative fluxes. In comparison with pristine clouds, the polluted clouds are more transparent in the afternoon due to smaller cloud fraction, smaller optical depth and larger droplets. As a result, the corresponding correlation between the surface radiative flux and ?a is positive (warming effect of aerosol). Also we found that relationship between cloud fraction and aerosol optical depth is cloud size dependent. The cloud fraction of large clouds (larger than 1 km) is relatively insensitive to the aerosol amount. In contrast, cloud fraction of small clouds (smaller than 1 km) is strongly positively correlated with ?a. This suggests that an ensemble of polluted clouds tends to be composed of smaller clouds than a similar one in a pristine environment. One should be aware of these time- and size-dependent features when qualitatively comparing N??a relationships obtained from the satellite observations, surface measurements, and model simulations

    Evaluation of aggregate stability methods for soil health

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    Public Interest Analysis of the US TPP Proposal for an IP Chapter

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    This briefing paper provides preliminary analysis of two leaked U.S. proposals for an intellectual property chapter in the Trans Pacific Partnership (TPP) agreement. The U.S. proposal, if adopted, would create the highest intellectual property protection and enforcement standards in any free trade agreement to date. Its provisions are primarily based on, and frequently go beyond, the maximalist and controversial standards of the Korea-US Free Trade Agreement (KORUS), the Anti-Counterfeiting Trade Agreement (ACTA) and US law, while negating the development-oriented flexibilities required by the 2007 New Trade Deal for developing countries and included in the US-Peru Free Trade Agreement. If adopted, the provisions would predictably lead to higher prices and decreased access to a broad range of consumer products in many TPP member countries, from medicines to textbooks to information on the internet, with little or no benefit from increased innovation, creativity or local economic activity. No country, including the US, has an interest in ceding this much policy flexibility to an international agreement. The proposal is particularly inappropriate for developing countries where the risks and effects of exclusionary pricing by monopolists are most acute

    Characterization of in band stray light in SBUV/2 instruments

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    Significant in-band stray light (IBSL) error at solar zenith angle (SZA) values larger than 77° near sunset in 4 SBUV/2 (Solar Backscattered Ultraviolet) instruments, on board the NOAA-14, 17, 18 and 19 satellites, has been characterized. The IBSL error is caused by large surface reflection and scattering of the air-gapped depolarizer in front of the instrument's monochromator aperture. The source of the IBSL error is direct solar illumination of instrument components near the aperture rather than from earth shine. The IBSL contamination at 273 nm can reach 40% of earth radiance near sunset, which results in as much as a 50% error in the retrieved ozone from the upper stratosphere. We have analyzed SBUV/2 albedo measurements on both the dayside and nightside to develop an empirical model for the IBSL error. This error has been corrected in the V8.6 SBUV/2 ozone retrieval

    External validation of ADO, DOSE, COTE and CODEX at predicting death in primary care patients with COPD using standard and machine learning approaches

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    Background Several models for predicting the risk of death in people with chronic obstructive pulmonary disease (COPD) exist but have not undergone large scale validation in primary care. The objective of this study was to externally validate these models using statistical and machine learning approaches. Methods We used a primary care COPD cohort identified using data from the UK Clinical Practice Research Datalink. Age-standardised mortality rates were calculated for the population by gender and discrimination of ADO (age, dyspnoea, airflow obstruction), COTE (COPD-specific comorbidity test), DOSE (dyspnoea, airflow obstruction, smoking, exacerbations) and CODEX (comorbidity, dyspnoea, airflow obstruction, exacerbations) at predicting death over 1–3 years measured using logistic regression and a support vector machine learning (SVM) method of analysis. Results The age-standardised mortality rate was 32.8 (95%CI 32.5–33.1) and 25.2 (95%CI 25.4–25.7) per 1000 person years for men and women respectively. Complete data were available for 54879 patients to predict 1-year mortality. ADO performed the best (c-statistic of 0.730) compared with DOSE (c-statistic 0.645), COTE (c-statistic 0.655) and CODEX (c-statistic 0.649) at predicting 1-year mortality. Discrimination of ADO and DOSE improved at predicting 1-year mortality when combined with COTE comorbidities (c-statistic 0.780 ADO + COTE; c-statistic 0.727 DOSE + COTE). Discrimination did not change significantly over 1–3 years. Comparable results were observed using SVM. Conclusion In primary care, ADO appears superior at predicting death in COPD. Performance of ADO and DOSE improved when combined with COTE comorbidities suggesting better models may be generated with additional data facilitated using novel approaches

    Describing interruptions, multi-tasking and task-switching in the community pharmacy: A qualitative study in England

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    Background: There is growing evidence base around interruptions and distractions in the community pharmacy setting. There is also evidence to suggest these practices may be associated with dispensing errors. Up to date, qualitative research on this subject is limited. Objective: To explore interruptions and distractions in the community setting; utilising an ethnographic approach to be able to provide a detailed description of the circumstances surrounding such practices. Setting: Community pharmacies in England, July to October 2011. Method: An ethnographic approach was taken. Non participant, unstructured observations were utilised to make records of pharmacists’ every activities. Case studies were formed by combining field notes with detailed information on pharmacists and their respective pharmacy businesses. Content analysis was undertaken both manually and electronically, utilising NVivo 10. Results: Response rate was 12% (n=11). Over fifteen days, a total of 123 hours and 58 minutes of observations were recorded in 11 separate pharmacies of 11 individual pharmacists. The sample was evenly split by gender (female n=6; male n=5) and pharmacy ownership (independent n=5; multiple n=6). Employment statuses included employee pharmacists (n=6), owners (n=4) and a locum (n=1). Average period of registration as a pharmacist was 19 years (range 5-39 years). Average prescriptions busyness of pharmacies ranged from 2,600 – 24,000 items dispensed per month. Two key themes were: “Interruptions and task-switching” and “distractions and multi-tasking.” All observed pharmacists’ work was dominated by interruptions, task-switches, distractions and multi-tasking, often to manage a barrage of conflicting demands. These practices were observed to be part of a deep-rooted culture in the community setting. Directional work maps illustrated the extent and direction of task switching employed by pharmacists. Conclusions: In this study pharmacists’ working practices were permeated by interruptions and multi-tasking. These practices are inefficient and potentially reduce patient safety in terms of dispensing accuracy
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