3,278 research outputs found

    Cold heteromolecular dipolar collisions

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    We present the first experimental observation of cold collisions between two different species of neutral polar molecules, each prepared in a single internal quantum state. Combining for the first time the techniques of Stark deceleration, magnetic trapping, and cryogenic buffer gas cooling allows the enhancement of molecular interaction time by 105^5. This has enabled an absolute measurement of the total trap loss cross sections between OH and ND3_3 at a mean collision energy of 3.6 cm−1^{-1} (5 K). Due to the dipolar interaction, the total cross section increases upon application of an external polarizing electric field. Cross sections computed from \emph{ab initio} potential energy surfaces are in excellent agreement with the measured value at zero external electric field. The theory presented here represents the first such analysis of collisions between a 2Π^2\Pi radical and a closed-shell polyatomic molecule.Comment: 7 pages, 5 figure

    Cold heteromolecular dipolar collisions

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    We present the first experimental observation of cold collisions between two different species of neutral polar molecules, each prepared in a single internal quantum state. Combining for the first time the techniques of Stark deceleration, magnetic trapping, and cryogenic buffer gas cooling allows the enhancement of molecular interaction time by 105^5. This has enabled an absolute measurement of the total trap loss cross sections between OH and ND3_3 at a mean collision energy of 3.6 cm−1^{-1} (5 K). Due to the dipolar interaction, the total cross section increases upon application of an external polarizing electric field. Cross sections computed from \emph{ab initio} potential energy surfaces are in excellent agreement with the measured value at zero external electric field. The theory presented here represents the first such analysis of collisions between a 2Π^2\Pi radical and a closed-shell polyatomic molecule.Comment: 7 pages, 5 figure

    Instagram as a Tool of Diffusion for the Livestock Industry

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    Studies have shown that more people are getting their information through social media (SM). With so much misinformation presented in global media, it is difficult for consumers to distinguish what is true and what isn’t. With negative images and minimal context, consumers have a tendency to believe and trust what they see on SM. After IRB approval, a survey study was launched on Qualtrics and accessed via email. Using Instagram as platform, this study presented 5 cognitively and 5 emotionally oriented posts focused on the aspects of animal welfare, diet/health, and environment/sustainability. Prior to viewing the Instagram posts, study participants were given a 5-scale Likert pre survey assessing their opinions about their views of animal welfare, diet/health of consumers of red meat and environment/sustainability for the beef industry. Participants subsequently viewed the posts and then took a post survey. SPSS was used to analyze responses with t-tests and frequencies. ATLAS was used to code for negative and positive key words in open responses. Results showed that participant’s views about the beef industry improved (p \u3c .05) after viewing the media posts for welfare and that participants favored the suggestions that beef cattle are treated humanely. Participants were unsure of the effects that beef consumption has on consumers’ diet and health as well as the environment. Qualitative results suggest that viewing of the posts had a favorable impact on consumer’s opinions

    1H-NMR urinary metabolomic profiling for diagnosis of gastric cancer

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    Background: Metabolomics has shown promise in gastric cancer (GC) detection. This research sought to identify whether GC has a unique urinary metabolomic profile compared with benign gastric disease (BN) and healthy (HE) patients. Methods: Urine from 43 GC, 40 BN, and 40 matched HE patients was analysed using 1H nuclear magnetic resonance (1H-NMR) spectroscopy, generating 77 reproducible metabolites (QC-RSD Results: GC displayed a clear discriminatory biomarker profile; the BN profile overlapped with GC and HE. LASSO-LR identified three discriminatory metabolites: 2-hydroxyisobutyrate, 3-indoxylsulfate, and alanine, which produced a discriminatory model with an area under the ROC of 0.95. Conclusions: GC patients have a distinct urinary metabolite profile. This study shows clinical potential for metabolic profiling for early GC diagnosis

    Methane Emissions from Process Equipment at Natural Gas Production Sites in the United States: Liquid Unloadings

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    Methane emissions from liquid unloadings were measured at 107 wells in natural gas production regions throughout the United States. Liquid unloadings clear wells of accumulated liquids to increase production, employing a variety of liquid lifting mechanisms. In this work, wells with and without plunger lifts were sampled. Most wells without plunger lifts unload less than 10 times per year with emissions averaging 21 000–35 000 scf methane (0.4–0.7 Mg) per event (95% confidence limits of 10 000–50 000 scf/event). For wells with plunger lifts, emissions averaged 1000–10 000 scf methane (0.02–0.2 Mg) per event (95% confidence limits of 500–12 000 scf/event). Some wells with plunger lifts are automatically triggered and unload thousands of times per year and these wells account for the majority of the emissions from all wells with liquid unloadings. If the data collected in this work are assumed to be representative of national populations, the data suggest that the central estimate of emissions from unloadings (270 Gg/yr, 95% confidence range of 190–400 Gg) are within a few percent of the emissions estimated in the EPA 2012 Greenhouse Gas National Emission Inventory (released in 2014), with emissions dominated by wells with high frequencies of unloadings

    Rethinking the patient: using Burden of Treatment Theory to understand the changing dynamics of illness

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    <b>Background</b> In this article we outline Burden of Treatment Theory, a new model of the relationship between sick people, their social networks, and healthcare services. Health services face the challenge of growing populations with long-term and life-limiting conditions, they have responded to this by delegating to sick people and their networks routine work aimed at managing symptoms, and at retarding - and sometimes preventing - disease progression. This is the new proactive work of patient-hood for which patients are increasingly accountable: founded on ideas about self-care, self-empowerment, and self-actualization, and on new technologies and treatment modalities which can be shifted from the clinic into the community. These place new demands on sick people, which they may experience as burdens of treatment.<p></p> <b>Discussion</b> As the burdens accumulate some patients are overwhelmed, and the consequences are likely to be poor healthcare outcomes for individual patients, increasing strain on caregivers, and rising demand and costs of healthcare services. In the face of these challenges we need to better understand the resources that patients draw upon as they respond to the demands of both burdens of illness and burdens of treatment, and the ways that resources interact with healthcare utilization.<p></p> <b>Summary</b> Burden of Treatment Theory is oriented to understanding how capacity for action interacts with the work that stems from healthcare. Burden of Treatment Theory is a structural model that focuses on the work that patients and their networks do. It thus helps us understand variations in healthcare utilization and adherence in different healthcare settings and clinical contexts

    A Comprehensive Catalogue of Variable Stars in the field of 47 Tucanae

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    We present the results of a comprehensive search for stellar variability in the globular cluster 47 Tucanae. Using the Mount Stromlo 40-inch (1m) telescope at Siding Spring Observatory and a combined V+R filter, we have detected 100 variable stars across a 52×52′\times52' field centered on the cluster. Here we present the V+R lightcurves and preliminary investigations of the detected variables, which comprise 28 Eclipsing Binaries (21 contact binaries and 7 detached systems), 45 RR Lyrae stars (41 of which belong to the SMC and four seemingly to the Galactic Halo), and 20 K-giant Long Period Variables (LPVs). We also detected four δ\delta Scuti stars, one TypeI Cepheid, and one TypeII Cepheid. One variable appears to be a dust-enshrouded SMC star with a short period pulsation. Of these 100 variables, 69 are new discoveries. Our eclipsing binary sample indicates a radial segregation in period, and includes two binaries that are seemingly orbited by low-luminosity stellar companions. One RR Lyrae star shows a Blahzko effect with remarkable regularity.Comment: 62 pages, 24 figures. Accepted for publication in AJ. For a full resolution version and variable star findercharts, see: http://www.mso.anu.edu.au/~dtf

    A Moving Magnetic Trap Decelerator: a New Source for Cold Atoms and Molecules

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    We present an experimental realization of a moving magnetic trap decelerator, where paramagnetic particles entrained in a cold supersonic beam are decelerated in a co-moving magnetic trap. Our method allows for an efficient slowing of both paramagnetic atoms and molecules to near stopping velocities. We show that under realistic conditions we will be able to trap and decelerate a large fraction of the initial supersonic beam. We present our first results on deceleration in a moving magnetic trap by bringing metastable neon atoms to near rest. Our estimated phase space volume occupied by decelerated particles at final velocity of 50 m/s shows an improvement of two orders of magnitude as compared to currently available deceleration techniques

    Massive migration from the steppe is a source for Indo-European languages in Europe

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    We generated genome-wide data from 69 Europeans who lived between 8,000-3,000 years ago by enriching ancient DNA libraries for a target set of almost four hundred thousand polymorphisms. Enrichment of these positions decreases the sequencing required for genome-wide ancient DNA analysis by a median of around 250-fold, allowing us to study an order of magnitude more individuals than previous studies and to obtain new insights about the past. We show that the populations of western and far eastern Europe followed opposite trajectories between 8,000-5,000 years ago. At the beginning of the Neolithic period in Europe, ~8,000-7,000 years ago, closely related groups of early farmers appeared in Germany, Hungary, and Spain, different from indigenous hunter-gatherers, whereas Russia was inhabited by a distinctive population of hunter-gatherers with high affinity to a ~24,000 year old Siberian6 . By ~6,000-5,000 years ago, a resurgence of hunter-gatherer ancestry had occurred throughout much of Europe, but in Russia, the Yamnaya steppe herders of this time were descended not only from the preceding eastern European hunter-gatherers, but from a population of Near Eastern ancestry. Western and Eastern Europe came into contact ~4,500 years ago, as the Late Neolithic Corded Ware people from Germany traced ~3/4 of their ancestry to the Yamnaya, documenting a massive migration into the heartland of Europe from its eastern periphery. This steppe ancestry persisted in all sampled central Europeans until at least ~3,000 years ago, and is ubiquitous in present-day Europeans. These results provide support for the theory of a steppe origin of at least some of the Indo-European languages of Europe

    Mapping Oil and Gas Development Potential in the US Intermountain West and Estimating Impacts to Species

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    Many studies have quantified the indirect effect of hydrocarbon-based economies on climate change and biodiversity, concluding that a significant proportion of species will be threatened with extinction. However, few studies have measured the direct effect of new energy production infrastructure on species persistence. in the western US and translate the build-out scenarios into estimated impacts on sage-grouse. We project that future oil and gas development will cause a 7–19 percent decline from 2007 sage-grouse lek population counts and impact 3.7 million ha of sagebrush shrublands and 1.1 million ha of grasslands in the study area.Maps of where oil and gas development is anticipated in the US Intermountain West can be used by decision-makers intent on minimizing impacts to sage-grouse. This analysis also provides a general framework for using predictive models and build-out scenarios to anticipate impacts to species. These predictive models and build-out scenarios allow tradeoffs to be considered between species conservation and energy development prior to implementation
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