The experimental characterization of a high‐power pulsed semiconductor laser operating in the eye‐safe spectral range (wavelength around 1.5 μm), with an asymmetric waveguide structure, a 100 μm wide ...stripe, and a bulk active layer positioned very close to the p‐cladding, is reported. An anti‐reflection/high reflection coated laser with a stripe width of 100 μm exhibits a single‐facet output power over 25 W at a pumping current amplitude of 100 A.
Trust is important for the perception of many types of risk, including those relating to genetically modified (GM) food. Who the public trusts in any given circumstance, however, is not well ...understood. In this study of public trust regarding GM food, an exploratory factor analysis with Promax rotation reveals public classification of three common institutional types—evaluators, watchdogs, and merchants. The structure of relationships among these stakeholders can act to enable or constrain public support for this new technology. Evaluators—scientists, universities, and medical professionals—are the most trusted. Watchdogs—consumer advocacy organizations, environmental organizations, and media sources—are moderately trusted. Merchants—grocers and grocery stores, industry, and farmers—are least trusted. While the federal government is seen as closest to being an evaluator, it is not highly correlated with any of the factors. The lack of trust in the organizations with the greatest resources and responsibilities for ensuring the safety of GM food should be seen as an important obstacle to the adoption of the technology.
The long baseline between Earth and the Sun makes solar neutrinos an excellent test beam for exploring possible neutrino decay. The signature of such decay would be an energy-dependent distortion of ...the traditional survival probability which can be fit for using well-developed and high-precision analysis methods. Here a model including neutrino decay is fit to all three phases of $^{8}\mathrm{B}$ solar neutrino data taken by the Sudbury Neutrino Observatory (SNO). This fit constrains the lifetime of neutrino mass state ${{\nu}}_{2}$ to be > $8.08\times{}{10}^{{-}5}\text{ }\text{ }\mathrm{s}/\mathrm{eV}$ at 90% confidence. An analysis combining this SNO result with those from other solar neutrino experiments results in a combined limit for the lifetime of mass state ${{\nu}}_{2}$ of > $1.92\times{}{10}^{{-}3}\text{ }\text{ }\mathrm{s}/\mathrm{eV}$ at 90% confidence.
The forward time projection chamber in STAR Ackermann, K.H.; Bieser, F.; Brady, F.P. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2003, Letnik:
499, Številka:
2
Journal Article
Recenzirano
Two cylindrical forward TPC detectors are described which were constructed to extend the phase space coverage of the STAR experiment to the region 2.5<|
η|<4.0. For optimal use of the available space ...and in order to cope with the high track density of central Au+Au collisions at RHIC, a novel design was developed using radial drift in a low diffusion gas. From prototype measurements a 2-track resolution of 1–
2
mm
is expected.
Background. The management of patients with severe, concomitant coronary and carotid artery occlusive disease is controversial.
Methods. Between 1975 and 1996, 512 patients (mean age, 64.9 years; 70% ...male) were admitted for coronary revascularization; 316 (61.7%) had asymptomatic, severe carotid disease (stenosis >70%) and 196 (38.3%) had symptomatic carotid disease (159 31.1% with transient ischemia and 37 7.2% with completed stroke). In group 1, coronary revascularization and carotid endarterectomy were simultaneously performed in 255 patients (49.8%) with unstable angina. In group 2 (staged approach), carotid endarterectomy was performed before coronary revascularization in 257 patients (50.2%) without unstable angina.
Results. Before 1986, the incidence of stroke and death was greater in group 1 (n = 149) than in group 2 (n = 156) (14 9.4% versus 4 2.6%;
p < 0.01). Since 1986, outcomes in group 1 (n = 106) and group 2 (n = 101) have been similar for stroke (2 1.9% versus 2 2.0%), death (4 3.8% versus 3 3.0%), and myocardial infarction (4 3.8% versus 5 5.0%). Significant univariate and multivariate predictors of adverse outcome were primarily heart-related (reoperation, intraaortic balloon use, ejection fraction <0.50, and angina grade 4 for death; age >70 years and congestive heart failure for stroke).
Conclusions. Despite highly selected populations, contemporary surgical results do not indicate that staged treatment of severe, concomitant coronary and carotid artery occlusive disease has an advantage over simultaneous treatment. Advances in myocardial protection and perioperative hemodynamic management may account for the low incidences of stroke and death in these operations.
Using 'general trust in institutions' and 'concepts of nature' as examples, the article analyzes the influence of cultural factors on sense-making of food biotechnology and the resulting public ...attitudes in the USA and Germany. According to the hypotheses investigated, different levels of trust and appreciation of nature explain part of the well-known differences in attitudes between both countries. The analysis of a cross-cultural survey of the general population shows that appreciation of nature is a predictor of attitudes in both countries. The higher appreciation of nature in Germany partly explains why attitudes towards food biotechnology are more negative in Germany than in the USA. The relationship between trust and attitudes is more complex than expected, however. Institutional trust is a moderate predictor of attitudes towards food biotechnology in the USA but not in Germany. To explain the varying effectiveness of trust in resolving innovation-related uncertainty we refer to differences in issue framing in both countries and to the higher degree of universalism and individualism in the USA. We conclude that the higher relevance of trust and the lower appreciation of nature make the U.S. culture more apt to assimilate technical innovations than the German culture.
E896 has measured Lambda production in 11.6A GeV/c Au-Au collisions over virtually the whole rapidity phase space. The midrapidity p(t) distributions have been measured for the first time at this ...energy and appear to indicate that the Lambda hyperons have different freeze-out conditions than protons. A comparison with the relativistic quantum molecular dynamics model shows that while there is good shape agreement at high rapidity the model predicts significantly different slopes of the m(t) spectra at midrapidity. The data, where overlap occurs, are consistent with previously reported measurements.
Background. Although an increasing number of elderly and high-risk patients, including those with generalized atherosclerosis, are undergoing coronary revascularization, few reports exist regarding ...the management of patients who have both occlusive disease of the great vessels and coronary artery disease.
Methods. Between 1972 and 1996, 31 consecutive patients (mean age, 56.5 years; 74% men) with multivessel coronary artery disease and symptomatic occlusive disease of the great vessels (25 single-vessel, 80.6%; 6 multiple-vessel, 19.4%) had 40 great vessels reconstructed by transthoracic bypass (n = 17, 42.5%), transthoracic endarterectomy (n = 8, 20%), or extrathoracic bypass (n = 15, 37.5%). All patients had simultaneous coronary artery bypass grafting (mean, 2.6 grafts per patient), and 8 patients had 10 distal carotid bifurcation endarterectomies (6 staged, 4 simultaneous).
Results. The early primary patency rate was 100%, and symptoms resolved completely in all 31 patients. There was 1 in-hospital death (3.2%) in a patient who had a respiratory arrest 11 days after operation. Perioperative morbidity included two myocardial infarctions (6.5%) and one opposite-hemisphere, embolic stroke (3.2%). Long-term follow-up of the 30 survivors (167.4 patient-years; mean, 5.6 years per patient) documented 5- and 10-year actuarial survival rates of 88.6% and 60.4%, respectively, with a 100% late brachiocephalic primary patency rate. Ten-year actuarial rates of freedom from the following events were as follows: death, 60.4%; myocardial infarction, 82.5%; stroke, 90.9%; percutaneous transluminal coronary angioplasty or redo coronary artery bypass grafting, 95.2%; and vascular operation or amputation, 78.4%.
Conclusions. Depending on the anatomic distribution of the disease, an integrated approach to great vessel reconstruction that incorporated transthoracic and extrathoracic approaches and techniques of endarterectomy and bypass resulted in few adverse outcomes and excellent long-term patency. Simultaneous revascularization of the great vessels and coronary arteries can produce immediate and long-term, symptom-free outcome with acceptably low operative risk.
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