2,460 research outputs found
The role of training and knowledge management in the organizational development of Prasar Bharati
No full textFirst person – Poonam Sehgal
No full textABSTRACT
First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping early-career researchers promote themselves alongside their papers. Poonam Sehgal is the first author on ‘Epidermal growth factor receptor and integrins control force-dependent vinculin recruitment to E-cadherin junctions’, published in Journal of Cell Science. The work in this article was carried out while Poonam was a postdoc in the lab of Dr Deborah Leckband at University of Illinois, Urbana-Champaign, USA, investigating the mechanism of E-cadherin-mediated force-transduction signaling in epithelial cells.</jats:p
Worst-case analysis of Omega-VaR ratio optimization model
No full textThe Omega ratio, a performance measure that separately considers upside and downside deviations from a fixed threshold, improves the Sharpe ratio by incorporating the higher-order moments. In this paper, we analyse the performance of a robust optimization model based on maximizing the worst-case of Omega ratio by taking its threshold point as the robust value of a defined percentile of the underlying loss distri-bution. To this aim, the threshold point is computed as the worst-case of the value-at-risk at a particular confidence level. We formulate robust model of the proposed strategy under two cases of uncertainty sets, the mixture distribution uncertainty and the box uncertainty. We show that, in the first case, the problem reduces to a second-order cone program (SOCP) and, in the second one, to a semi-definite pro-gram (SDP), hence tractable in both the cases. We conduct a comprehensive empirical investigation of the proposed models over six data sets across the globe, namely BSE 100 (India), FTSE 100 (UK), Hang Seng (Hong Kong), S&P Asia 50 (Asia), Dow Jones Industrial Average (USA), and IBEX (Spain). We compare our models with the three variants of the Omega ratio model, one its robust variant taking worst-case condi-tional value-at-risk as threshold point, and two of its nominal variants using value-at-risk and conditional value-at-risk as threshold points, respectively. We find that the proposed model under mixture distribu-tion uncertainty exhibits a better performance over most of the data sets and scenarios than its CVaR-based robust counterpart. Under the box set, the proposed model performs similar or generates mixed results compared to its CVaR-based robust counterpart model. We also note that both the proposed ro-bust models save investors against the risk of losses over the bearish phase of market in comparison to their nominal counterparts. Finally, on comparing the proposed model under mixture distribution uncer-tainty with the box uncertainty, the former model is found to be more suitable for optimistic investors, whereas the later strategy is more ideal for pessimistic investors.(c) 2022 Elsevier Ltd. All rights reserved
The life and the contribution of B. R. Sehgal, G. Yadigaroglu and G. Hewitt: remembrance statements
No full textSolicited or voluntary statements have been collected by the Editor of the Special Issue (SI). Tributes to Sehgal, Yadigaroglu and Hewitt are reported in the alphabetical order of those who originated them. The concise tributes by N. Todreas related to all the three scientists constitute the paper PII-1 in this SI and are also reported hereafter. Romney Duffey and John Jones wrote dedicated tributes with scientific insights which constitute PII-7 and PII-8 in this SI. A number of others helped with biographies of Sehgal, Yadigaroglu and Hewitt and are acknowledged in paper PII-2
Making Movement Memorable Tino Sehgal and Boris Charmatz at Tate
No full textThis chapter reflects on the implications of memory and practices of remembrance in performance- and choreographic-based exhibitions and events inside museums by focusing on the works and poetics of Tino Sehgal and Boris Charmatz and their collaborations with Tate Modern in London. Discussing the increasing tendency to host performances and contemporary dance in museums and art galleries over the past two decades, the author considers how dance and performance constitute effective tools for challenging theoretical and museum discourses on documentation and preservation and for exploring the politics of memory and participation. Starting from a shared germinal idea about a dancing museum, Sehgal and Charmatz have contributed to the recent shift of the museum towards the acquisition of performance- and choreographic-based artworks and to the empowerment of their audience. In conclusion, the chapter argues that their works resulted in opposing strategies, revealing both the potential within and the problematic aspects of the current dialogue between the museum and these dance- and performance-based artworks
Exploring Fixed-Point Results Using Random Sehgal Contraction in Symmetric Random Cone Metric Spaces with Applications
No full textThis paper introduces a new concept of random Sehgal contraction in the setting of random cone metric spaces. We explore the modern advancements of traditional fixed-point theorems in a random setting, elaborating on the Sehgal–Guseman fixed-point theorem within the realm of random cone metric spaces. A significant aspect of our research is the interplay between symmetry and randomness; while symmetry provides a framework for understanding structural properties, randomness introduces complexity, which can lead to unexpected behaviors. Our research provides a deeper understanding of the classical results and incorporates a detailed example to illustrate our findings. In addition, major random fixed-point results are also established, which could be applied to nonlinear random fractional differential equations (FDEs) and integral equations as well as to random boundary value problems (BVPs) related to homogeneous random transverse bars
Efficacy of ozone against stored grain insect species in wheat: laboratory and field observations
No full textAdults of the lesser grain borer, Rhyzopertha dominica (F.), were exposed to an ozone concentration of 0.43 or 0.86 g/m3 for 15-36 h or 4-30 h to estimate lethal time (LT) and lethal dose (LD, or concentration x time (Ct) product) to kill 99% of the adults at 28°C and 65% r.h. After ozone exposure adult mortality was counted daily for 5 d. At 0.43 and 0.86 g/m3, the LT99 values for adult mortality on day 1 were about 67 and 42 h, respectively. Corresponding LD99 values for adult mortality were 28 and 36 g-h/m3, respectively. On day 5, the LT99 and LD99 values decreased by 52 to 54% of day 1 values. Doubling the ozone concentration did not reduce the LT99 values by half. In general, the LD99 values on days 1 through 5 at an ozone concentration of 0.86 g/m3 were significantly greater than similar values at an ozone concentration of 0.43 g/m3. This suggested that R. dominica adults tend to be more susceptible when exposed for long time period to a low ozone concentration. In a bin holding 125 MT of hard red winter wheat, ozone was flushed through the grain mass for 5 d. Ozone concentrations at the plenum showed an increase from 0 to 0.107 g/m3. All adults of R. dominica; the rusty grain beetle, Cryptolestes ferrugineus (Stephens), Tribolium castaneum (Herbst), and eggs of the Indian meal moth, Plodia interpunctella (Hübner), in bioassays succumbed to ozonation. A laboratory strain and four phosphine-resistant field strains of the red flour beetle, T. castaneum, and a laboratory strain and two phosphine-resistant field strains of R. dominica were exposed to 0.43 and 0.86 g/m3 of ozone for 24 h. After one day of incubation following the 24h exposure, the mortality of the laboratory and phosphine-resistant field strains of both species was 100%
Bibliometric Analysis of Emerging Bond Market Research: Performance Insights and Science Mapping
No full textThis bibliometric paper investigates the research landscape in emerging bond market literature, spanning 1993 to 2023, and encompasses a total of 325 research articles. Employing a multifaceted approach, it begins by examining publication trends, core journals, prominent authors, influential articles, and keyword dynamics, providing a comprehensive overview of research dynamics in this domain. Beyond performance analysis, the study ventures into science mapping using co-word analysis to uncover the underlying conceptual structure of the emerging bond market field. The bibliographic data has been drawn from Scopus and analyzed using the Bibliometrix R package, providing insights into the current dimensions of emerging bond market studies. This analysis facilitated the identification of five major keyword clusters, i.e., sovereign bonds, the impact of financial crises, yield curve, corporate bonds, and Islamic bonds in the emerging bond market space. Based on these themes, the study also suggests avenues for future scholarly exploration in this specialized field
Measuring the growth of structure with multi-wavelength surveys of galaxy clusters
No full textCurrent and near-future galaxy cluster surveys at a variety of wavelengths are expected to provide a promising way to obtain precision measurements of the growth of structure over cosmic time. This in turn would serve as an important precision probe of cosmology. However, to realize the full potential of these surveys, systematic uncertainties arising from, for example, cluster mass estimates and sample selection must be well understood. This work follows several different approaches towards alleviating these uncertainties.
Cluster sample selection is investigated in the context of arcminute-resolution millimeter-wavelength surveys such as the Atacama Cosmology Telescope (ACT) and the South Pole Telescope (SPT). Large-area, realistic simulations of the microwave sky are constructed and cluster detection is simulated using a multi-frequency Wiener filter to separate the galaxy clusters, via their Sunyaev-Zel'dovich signal, from other contaminating microwave signals. Using this technique, an ACT-like survey can expect to obtain a cluster sample that is 90% complete and 85% pure above a mass of 3 x 10^14 Msun.
Cluster mass uncertainties are explored by comparing X-ray and weak-lensing mass estimates for shear-selected galaxy clusters in the Deep Lens Survey (DLS) to study possible biases in using cluster baryons or weak-lensing shear as tracers of the cluster total mass. Results are presented for four galaxy clusters that comprise the top-ranked shear-selected system in the DLS, and for three of these clusters there is agreement between X-ray and weak-lensing mass estimates. For the fourth cluster, the X-ray mass estimate is higher than that from weak-lensing by 2-sigma, and X-ray images suggest this cluster may be undergoing a merger with a smaller cluster, which may be biasing the X-ray mass estimate high.
The feasibility of measuring galaxy cluster peculiar velocities using an ACT-like instrument is also investigated. Such a possibility would allow one to measure structure growth via large-scale velocity fields and circumvent the uncertainties associated with measuring cluster masses. We show that such measurements are possible and yield statistical uncertainties of roughly 100 km/sec given either a temperature prior with 1-sigma errors of less than 2 keV or additional lower frequency millimeter-band observations.Ph.D.Includes bibliographical references
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