1,387 research outputs found

    Efficiency at optimal work from finite reservoirs: a probabilistic perspective

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    We revisit the classic thermodynamic problem of maximum work extraction from two arbitrary sized hot and cold reservoirs, modelled as perfect gases. Assuming ignorance about the extent to which the process has advanced, which implies an ignorance about the final temperatures, we quantify the prior information about the process and assign a prior distribution to the unknown temperature(s). This requires that we also take into account the temperature values which are regarded to be unphysical in the standard theory, as they lead to a contradiction with the physical laws. Instead in our formulation, such values appear to be consistent with the given prior information and hence are included in the inference. We derive estimates of the efficiency at optimal work from the expected values of the final temperatures, and show that these values match with the exact expressions in the limit when any one of the reservoirs is very large compared to the other. For other relative sizes of the reservoirs, we suggest a weighting procedure over the estimates from two valid inference procedures, that generalizes the procedure suggested earlier in [J. Phys. A: Math. Theor. {\bf 46}, 365002 (2013)]. Thus a mean estimate for efficiency is obtained which agrees with the optimal performance to a high accuracy.Comment: 14 pages, 6 figure

    Scalar FCNC and rare top decays in a two Higgs doublet model "for the top"

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    In the so called two Higgs doublet model for the top-quark (T2HDM), first suggested by Das and Kao, the top quark receives a special status, which endows it with a naturally large mass, and also potentially gives rise to large flavor changing neutral currents (FCNC) only in the up-quark sector. In this paper we calculate the branching ratio (BR) for the rare decays t->ch and h->tc (h is a neutral Higgs) in the T2HDM, at tree level and at 1-loop when it exceeds the tree-level. We compare our results to predictions from other versions of 2HDM's and find that the scalar FCNC in the T2HDM can play a significant role in these decays. In particular, the 1-loop mediated decays can be significantly enhanced in the T2HDM compared to the 2HDM of types I and II, in some instances reaching BR~10^-4 which is within the detectable level at the LHC.Comment: added two references. 15 pages, 14 figure

    Rethinking First Language–Second Language Similarities and Differences in English Proficiency: Insights From the ENglish Reading Online (ENRO) Project

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    This article presents the ENglish Reading Online (ENRO) project that offers data on English reading and listening comprehension from 7,338 university-level advanced learners and native speakers of English representing 19 countries. The database also includes estimates of reading rate and seven component skills of English, including vocabulary, spelling, and grammar, as well as rich demographic and language background data. We first demonstrate high reliability for ENRO tests and their convergent validity with existing meta-analyses.We then provide a bird’s-eye view of first (L1) and second (L2) language comparisons and examine the relative role of various predictors of reading and listening comprehension and reading speed. Across analyses, we found substantially more overlap than differences between L1 and L2 speakers, suggesting that English reading proficiency is best considered across a continuum of skill, ability, and experiences spanning L1 and L2 speakers alike. We end by providing pointers for how researchers can mine ENRO data for future studies.Este artículo se encuentra publicado en Language Learning, 73(1)

    Assessment of the functional outcome of multiple discs prolapses treated with discectomy and surgical stabilization in tertiary care hospital in Salem district

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    Background:  Low back pain affect up to 80% of people in the modern world at some point in their lives, creating high rates of activity limitation, work absence, impaired quality of life, and the need for medical care. To assess the functional outcome of patients with multiple discs prolapses treated with discectomy and surgical stabilization.Methods: A longitudinal study was conducted in the orthopedics department of Vinayaka missions Kirupananda Variyar medical college, Salem for two years between August 2019 and July 2020. A total of 30 patients presenting with lumbar disc herniation with radiculopathy and neurological deficits were included in the study. The diagnosis was confirmed by doing an X-ray and MRI of the lumbosacral spine. Patients were followed up for 6 months and the nature of the pain was assessed post-operatively using the Japanese orthopedic association system scoring for low back pain. It ranges from 0-15. Score 0 is the worst pain and 15 is normal.Results: The mean Japanese association score for low back pain was 7.2 before the surgical procedure and it was 12 after the procedure and the difference was found to be statistically significant. Among the postoperative complications, 4 patients developed failback syndrome and 1 patient had implant failure.Conclusios: Relief of radicular pain was associated with subjective satisfaction with the surgery among our study population, as evidenced by the decrease in radicular pain and the subjective satisfaction with the operation

    Phytochemical and antimycobacterial analysis of aqueous and ethanolic extracts of Annona muricata Linn (Soursop)

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    Against the backdrop evidenced in the threat Tuberculosis poses to developing economies, especially its prevalence among people in their productive (15-45) years; this preliminary study examined the phytochemical constituents and antimycobacterial effect of four (4) aqueous and ethanolic extracts from the fruit skin (epicarp) and leaf of Annona muricata Linn

    Human and computer estimations of predictability of words on written language

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    When we read printed text, we continuously predict the follow words in order to integrate information and direct future eye movements to forthcoming words. Thus the Predictability has become one the most important variables when explaining human behavior and information processing during reading. In this study we present results of word predictability in long Spanish texts, estimated from human responses in a massive web-based task. We used Latent Semantic Analysis (LSA) as a way to estimate human-based predictability values computationally. We validated the human estimation of predictability with local and global properties of the text, and we showed that LSA-distance on adequate timescale captures some semantic aspects of the prediction.Sociedad Argentina de Informática e Investigación Operativ
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