10 research outputs found

    Identification of Grand-design and Flocculent Spirals from SDSS using Convolutional Neural network

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    Spiral galaxies can be classified into the {\it Grand-designs} and {\it Flocculents} based on the nature of their spiral arms. The {\it Grand-designs} exhibit almost continuous and high contrast spiral arms and are believed to be driven by density waves, while the {\it Flocculents} have patchy and low-contrast spiral features and are primarily stochastic in origin. We train a convolutional neural network (CNN) model to classify spirals into {\it Grand-designs} and {\it Flocculents}, with a testing accuracy of 97.2%\mathrm{97.2\%}. We then use the above model for classifying 1,354\mathrm{1,354} new spirals from the SDSS. Out of these, 721\mathrm{721} were identified as {\it Flocculents}, and the rest as {\it Grand-designs}. We find the median asymptotic rotational velocities of our newly classified {\it Grand-designs} and {\it Flocculents} are 218±86218 \pm 86 and 145±67145 \pm 67 respectively, indicating that the {\it Grand-designs} are mostly the high-mass and the {\it Flocculents} the intermediate-mass spirals. This is further corroborated by the observation that the median morphological indices of the {\it Grand-designs} and {\it Flocculents} are 2.6±1.82.6 \pm 1.8 and 4.7±1.94.7 \pm 1.9 respectively, implying that the {\it Flocculents} primarily consist of a late-type galaxy population in contrast to the {\it Grand-designs}. Finally, an almost equal fraction of of bars \sim 0.3 in both the classes of spiral galaxies reveals that the presence of a bar component does not regulate the type of spiral arm hosted by a galaxy. Our results may have important implications for formation and evolution of spiral arms in galaxies.Comment: 19 pages, 8 figures (Accepted for publication in the MNRAS

    A Methodology for Successful University Graduate CubeSat Programs

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    The University of Colorado Smead Department of Aerospace Engineering has over a decade of success in designing, building, and operating student led CubeSat missions. The experience and lessons learned from building and operating the CSSWE, MinXSS-1, MinXSS-2, and QB50-Challenger missions have helped grow a knowledge base on the most effective and efficient ways to manage some of the “tall poles” when it comes to student run CubeSat missions. Among these “tall poles” we have seen student turnover, software, and documentation become some of the hardest to knock-down and we present our strategies for doing so. We use the MAXWELL mission (expected to launch in 2021) as a road-map to detail the methodology we have built over the last decade to ensure the greatest chance of mission success

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    National Agricultural Bioinformatics Grid Project under National Agricultural Innovation Project.White spot disease is a devastating disease of shrimp Penaeus monodon in which the shrimp receptor protein PmRab7 interacts with viral envelop protein VP28 to form PmRab7-VP28 complex, which causes initiation of the disease. The molecular mechanism implicated in the disease, the dynamic behavior of proteins as well as interaction between both the biological counterparts that crafts a micro-environment feasible for entry of virus into the shrimp is still unknown. In the present study, we applied molecular modeling (MM), molecular dynamics (MD) and docking to compute surface mapping of infective amino acid residues between interacting proteins. Our result showed that α-helix of PmRab7 (encompassing Ser74, Ile143, Thr184, Arg53, Asn144, Thr184, Arg53, Arg79) interacts with β-sheets of VP28 (containing Ser74, Ile143, Thr184, Arg53, Asn144, Thr184, Arg53, Arg79) and Arg69-Ser74, Val75-Ile143, Leu73-Ile143, Arg79-Asn144, Ala198-Ala182 bonds contributed in the formation of PmRab7-VP28 complex. Further studies on the amino acid residues and bonds may open new possibilities for preventing PmRab7-VP28 complex formation, thus reducing chances of WSD. The quantitative predictions provide a scope for experimental testing in future as well as endow with a straightforward evidence to comprehend cellular mechanisms underlying the disease.Indian Council of Agricultural research, New Delhi

    Health-status outcomes with invasive or conservative care in coronary disease

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    BACKGROUND In the ISCHEMIA trial, an invasive strategy with angiographic assessment and revascularization did not reduce clinical events among patients with stable ischemic heart disease and moderate or severe ischemia. A secondary objective of the trial was to assess angina-related health status among these patients. METHODS We assessed angina-related symptoms, function, and quality of life with the Seattle Angina Questionnaire (SAQ) at randomization, at months 1.5, 3, and 6, and every 6 months thereafter in participants who had been randomly assigned to an invasive treatment strategy (2295 participants) or a conservative strategy (2322). Mixed-effects cumulative probability models within a Bayesian framework were used to estimate differences between the treatment groups. The primary outcome of this health-status analysis was the SAQ summary score (scores range from 0 to 100, with higher scores indicating better health status). All analyses were performed in the overall population and according to baseline angina frequency. RESULTS At baseline, 35% of patients reported having no angina in the previous month. SAQ summary scores increased in both treatment groups, with increases at 3, 12, and 36 months that were 4.1 points (95% credible interval, 3.2 to 5.0), 4.2 points (95% credible interval, 3.3 to 5.1), and 2.9 points (95% credible interval, 2.2 to 3.7) higher with the invasive strategy than with the conservative strategy. Differences were larger among participants who had more frequent angina at baseline (8.5 vs. 0.1 points at 3 months and 5.3 vs. 1.2 points at 36 months among participants with daily or weekly angina as compared with no angina). CONCLUSIONS In the overall trial population with moderate or severe ischemia, which included 35% of participants without angina at baseline, patients randomly assigned to the invasive strategy had greater improvement in angina-related health status than those assigned to the conservative strategy. The modest mean differences favoring the invasive strategy in the overall group reflected minimal differences among asymptomatic patients and larger differences among patients who had had angina at baseline

    Initial invasive or conservative strategy for stable coronary disease

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    BACKGROUND Among patients with stable coronary disease and moderate or severe ischemia, whether clinical outcomes are better in those who receive an invasive intervention plus medical therapy than in those who receive medical therapy alone is uncertain. METHODS We randomly assigned 5179 patients with moderate or severe ischemia to an initial invasive strategy (angiography and revascularization when feasible) and medical therapy or to an initial conservative strategy of medical therapy alone and angiography if medical therapy failed. The primary outcome was a composite of death from cardiovascular causes, myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. A key secondary outcome was death from cardiovascular causes or myocardial infarction. RESULTS Over a median of 3.2 years, 318 primary outcome events occurred in the invasive-strategy group and 352 occurred in the conservative-strategy group. At 6 months, the cumulative event rate was 5.3% in the invasive-strategy group and 3.4% in the conservative-strategy group (difference, 1.9 percentage points; 95% confidence interval [CI], 0.8 to 3.0); at 5 years, the cumulative event rate was 16.4% and 18.2%, respectively (difference, 121.8 percentage points; 95% CI, 124.7 to 1.0). Results were similar with respect to the key secondary outcome. The incidence of the primary outcome was sensitive to the definition of myocardial infarction; a secondary analysis yielded more procedural myocardial infarctions of uncertain clinical importance. There were 145 deaths in the invasive-strategy group and 144 deaths in the conservative-strategy group (hazard ratio, 1.05; 95% CI, 0.83 to 1.32). CONCLUSIONS Among patients with stable coronary disease and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of ischemic cardiovascular events or death from any cause over a median of 3.2 years. The trial findings were sensitive to the definition of myocardial infarction that was used
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