1,865 research outputs found
Crystallization and preliminary X-ray diffraction studies of a novel alcohol dehydrogenase from the hyperthermophilic archaeon Aeropyrum pernix.
Journal ArticleResearch Support, Non-U.S. Gov'tA novel alcohol dehydrogenase enzyme has been cloned from the hyperthermophilic archaeon Aeropyrum pernix and overexpressed in Escherichia coli. This zinc-containing enzyme has been crystallized by the sitting-drop vapour-diffusion method using PEG 600 as precipitant. The crystals diffract to 1.5 A resolution and belong to the orthorhombic space group P2(1)2(1)2, with unit-cell parameters a = 100.7, b = 103.2, c = 67.5 A. The asymmetric unit contains two enzyme monomers. Two synchrotron data sets have been collected: one at a wavelength near the absorption edge of zinc and one at a remote wavelength. Three strong zinc-ion positions were visible in the anomalous Patterson map. Two additional weaker zinc ions have been identified by anomalous Fourier synthesis.BBSRCEuropean Community (Access to Research Infrastructure Action of the Improving Human Potential Programme to EMBL Hamburg Outstation
Room temperature plasmon laser by total internal reflection
Plasmon lasers create and sustain intense and coherent optical fields below
light's diffraction limit with the unique ability to drastically enhance
light-matter interactions bringing fundamentally new capabilities to
bio-sensing, data storage, photolithography and optical communications.
However, these important applications require room temperature operation, which
remains a major hurdle. Here, we report a room temperature semiconductor
plasmon laser with both strong cavity feedback and optical confinement to
1/20th of the wavelength. The strong feedback arises from total internal
reflection of surface plasmons, while the confinement enhances the spontaneous
emission rate by up to 20 times.Comment: 8 Page, 2 Figure
Development of the My Cult-Rural Toolkit
The EU H2020 RURITAGE project takes 20 case studies, considered to be Role Models (RMs) of successful heritage-led rural regeneration from Europe, to analyze them and transfer knowledge and learning to a network of Replicators (Rs). To quantify the success of these RURITAGE interventions, a monitoring framework has been developed which includes a range of Key Performance Indicators (KPI) and a co-monitoring program. This program takes a bottom-up approach working with key stakeholders to understand their values. The My Cult-Rural Toolkit described in this paper has been designed and developed to support the co-monitoring program. The toolkit includes various methods allowing expert and non-expert engagement with the landscape valuation process through embodied and situated approaches. All the co-monitoring tools share the principle of gathering data through real-time interaction in the place of interest, following principles of the embodied approach to ecosystemsâ valuation. The toolkit employs both participatory hands-on workshops (Mini-Landscapes, Object Mapping, and Walking Maps) for in-depth understanding of values attached with landscape, and digital mobile apps (Rate my View App and Landscape Connect App) for exploratory, participatory mapping. This paper describes the toolkit and discusses benefits and limitations of its usage in the context of co-monitoring of cultural and natural heritage (CNH) inspired rural change.</jats:p
Point-of-care screening for a current Hepatitis C virus infection: influence on uptake of a concomitant offer of HIV screening
Eliminating hepatitis C as a public health threat requires an improved understanding of how to increase testing uptake. We piloted point-of-care testing (POCT) for a current HCV infection in an inner-city Emergency Department (ED) and assessed the influence on uptake of offering concomitant screening for HIV. Over four months, all adults attending ED with minor injuries were first invited to complete an anonymous questionnaire then invited to test in alternating cycles offering HCV POCT or HCV+HIV POCT. Viral RNA was detected in finger-prick blood by GeneXpert. 814/859 (94.8%) questionnaires were returned and 324/814 (39.8%) tests were accepted, comprising 211 HCV tests and 113 HCV+HIV tests. Offering concomitant HIV screening reduced uptake after adjusting for age and previous HCV testing (odds ratio 0.51; 95% confidence interval [CI] 0.38â0.68; pâ<â0.001). HCV prevalence was 1/324 (0.31%; 95% CI 0.05â1.73); no participant tested positive for HIV. 167/297 (56.2%) POCT participants lived in the most deprived neighbourhoods in England. HCV RNA testing using finger-prick blood was technically feasible. Uptake was moderate and the offer of concomitant HIV screening showed a detrimental impact on acceptability in this low prevalence population. The findings should be confirmed in a variety of other community settings
Esophageal perforation caused by external air-blast injury
<p>Abstract</p> <p>Background</p> <p>Esophageal perforation after external air-blast trauma is rarely presented in the emergency room. The diagnosis is often delayed more than 24 hours.</p> <p>Methods</p> <p>We review the literature and report a case of esophageal perforation caused by external air-blast injury.</p> <p>Results</p> <p>Including the present case, a total of 5 cases of esophageal perforation were caused by external air-blast injury in English literature. Of them, the common presentations were chest pain and dyspnea. The treatment methods varied with each case. One patient died before diagnosis of esophageal perforation and the others survived after proper surgical management.</p> <p>Conclusions</p> <p>Early diagnosis and proper surgical management can reduce the morbidity and mortality of patients who suffered from esophageal perforation caused by external air-blast injury.</p
Doing good by doing nothing? The role of social norms in explaining default effects in altruistic contexts
We explore whether the known preference for default options in choice contextsâdefault effectsâoccur in altruistic contexts and the extent to which this can be explained through appeal to social norms. In four experiments, we found that (i) participants were more likely to donate money to charity when this was the default option in an altruistic choice context; (ii) participants perceived the default option to be the socially normative option; (iii) perceptions of social norms mediated the relationship between default status and charitable donations; and (iv) a transfer effect, whereby participants translated social norms they inferred from the default option in one domain into behavior in a second, related domain. Theoretically, our analysis situates default effects within a comprehensive body of social psychological research concerning social norms and the attitudeâbehavior relationship, providing novel empirical predictions. Practically, these findings highlight that the way donation policies are framed can have an important impact on donation behavior: in our third study, we found that 81% donated half of their earnings for taking part in the experiment to charity when this was the default option, compared with only 19% when keeping the money was the default. Our work suggests that making use of default effects could be an effective tool to increase altruistic behavior without compromising freedo
A Giant Colonic Hamartoma and Multiple Colonic Hamartomatous Polyps in a Middle-Aged Man
Colonic hamartomas are rare polypoid lesions. We report an unusual case of multiple colonic hamartomatous polyps, including a giant hamartoma, unrelated to hereditary or familial polyposis syndromes, in a 48-year-old man. The diameter of the largest polyp was 9.5 cm, and endoscopy revealed that the lesion caused colonic obstruction. The clinical, endoscopic and histological aspects of this case are discussed
Effective recruitment of participants to a phase I study using the internet and publicity releases through charities and patient organisations: analysis of the adaptive study of IL-2 dose on regulatory T cells in type 1 diabetes (DILT1D).
A barrier to the successful development of new disease treatments is the timely recruitment of participants to experimental medicine studies that are primarily designed to investigate biological mechanisms rather than evaluate clinical efficacy. The aim of this study was to analyse the performance of three recruitment sources and the effect of publicity events during the Adaptive study of IL-2 dose on regulatory T cells in type 1 diabetes (DILT1D).This work is funded by the JDRF (9-2011-253), the Wellcome Trust (091157) and the National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre. The research leading to these results has received funding from the European Unionâs Seventh Framework Programme (FP7/2007-2013) under grant agreement number 241447 (NAIMIT). The Cambridge Institute for Medical Research (CIMR) is in receipt of a Wellcome Trust Strategic Award (100140).This is the final version of the article. It first appeared from BMC via http://dx.doi.org/10.1186/s13063-015-0583-
Allowed and forbidden transitions in artificial hydrogen and helium atoms
The strength of radiative transitions in atoms is governed by selection
rules. Spectroscopic studies of allowed transitions in hydrogen and helium
provided crucial evidence for the Bohr's model of an atom. Forbidden
transitions, which are actually allowed by higher-order processes or other
mechanisms, indicate how well the quantum numbers describe the system. We apply
these tests to the quantum states in semiconductor quantum dots (QDs), which
are regarded as artificial atoms. Electrons in a QD occupy quantized states in
the same manner as electrons in real atoms. However, unlike real atoms, the
confinement potential of the QD is anisotropic, and the electrons can easily
couple with phonons of the material. Understanding the selection rules for such
QDs is an important issue for the manipulation of quantum states. Here we
investigate allowed and forbidden transitions for phonon emission in one- and
two-electron QDs (artificial hydrogen and helium atoms) by electrical
pump-and-probe experiments, and find that the total spin is an excellent
quantum number in artificial atoms. This is attractive for potential
applications to spin based information storage.Comment: slightly longer version of Nature 419, 278 (2002
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