468 research outputs found

    A Multiple-range Self-balancing Thermocouple Potentiometer

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    A multiple-range potentiometer circuit is described that provides automatic measurement of temperatures or temperature differences with any one of several thermocouple-material pairs. Techniques of automatic reference junction compensation, span adjustment, and zero suppression are described that permit rapid selection of range and wire material, without the necessity for restandardization, by setting of two external tap switches

    prior shared experience and survival of spin-offs from restructured state enterprises

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    Many organizations, especially in emerging economies, trace their origins to restructured state enterprises, and this study explores the implications of such origins for organizational adaptation to changing environmental conditions. We compare the activity choices and survival chances of spin-offs from restructured state enterprises with those of de novo organizations. We argue that prior shared experience of spin-offs’ managers and employees facilitates the redeployment of routines developed in parent state enterprises. This should predispose spin-offs to pursue familiar activities, but this choice is not completely predetermined, and its survival implications depend on the environmental conditions. Our empirical findings suggest that spin-offs from restructured state enterprises are less likely to engage in new activities than de novo organizations. However, those restructuring spin-offs that do engage in new activities before the regulatory regime shift significantly improve their survival chances after the shift. Moreover, we find that the detrimental effect of the regulatory regime shift and the beneficial effect of engaging in new activities are stronger for spin-offs from restructured state enterprises than for de novo organizations.authorsversionpublishe

    The effect of equal-channel angular pressing on microstructure, mechanical properties, and biodegradation behavior of magnesium alloyed with silver and gadolinium

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    The effect of equal channel angular pressing (ECAP) on the microstructure, texture, mechanical properties, and corrosion resistance of the alloys Mg-6.0%Ag and Mg-10.0%Gd was studied. It was shown that ECAP leads to grain refinement of the alloys down to the average grain size of 2–3 ÎŒm and 1–2 ÎŒm, respectively. In addition, in both alloys the precipitation of fine particles of phases Mg54_{54}Ag17_{17} and Mg5_{5}Gd with sizes of ~500–600 and ~400–500 nm and a volume fraction of ~9% and ~8.6%, respectively, was observed. In the case of the alloy Mg-6.0%Ag, despite a significant grain refinement, a drop in the strength characteristics and a nearly twofold increase in ductility (up to ~30%) was found. This behavior is associated with the formation of a sharp inclined basal texture. For alloy Mg-10.0%Gd, both ductility and strength were enhanced, which can be associated with the combined effect of significant grain refinement and an increased probability of prismatic and basal glide. ECAP was also shown to cause a substantial rise of the biodegradation rate of both alloys and an increase in pitting corrosion. The latter effect is attributed to an increase in the dislocation density induced by ECAP and the occurrence of micro-galvanic corrosion at the matrix/particle interfaces

    Unintentional high density p-type modulation doping of a GaAs/AlAs core-multi-shell nanowire

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    Achieving significant doping in GaAs/AlAs core/shell nanowires (NWs) is of considerable technological importance but remains a challenge due to the amphoteric behavior of the dopant atoms. Here we show that placing a narrow GaAs quantum well in the AlAs shell effectively getters residual carbon acceptors leading to an \emph{unintentional} p-type doping. Magneto-optical studies of such a GaAs/AlAs core multi-shell NW reveal quantum confined emission. Theoretical calculations of NW electronic structure confirm quantum confinement of carriers at the core/shell interface due to the presence of ionized carbon acceptors in the 1~nm GaAs layer in the shell. Micro-photoluminescence in high magnetic field shows a clear signature of avoided crossings of the n=0n=0 Landau level emission line with the n=2n=2 Landau level TO phonon replica. The coupling is caused by the resonant hole-phonon interaction, which points to a large 2D hole density in the structure.Comment: just published in Nano Letters (http://pubs.acs.org/doi/full/10.1021/nl500818k

    Endogenous ownership structure:factors affecting the post-privatisation equity in largest Hungarian firms

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    Using a data set for the 162 largest Hungarian firms during the period of 1994-1999, this paper explores the determinants of equity shares held by both foreign investors and Hungarian corporations. Evidence is found for a post-privatisation evolution towards more homogeneous equity structures, where dominant categories of Hungarian and foreign owners aim at achieving controlling stakes. In addition, focusing on firm-level characteristics we find that exporting firms attract foreign owners who acquire controlling equity stakes. Similarly, firm-size measurements are positively associated with the presence of foreign investors. However, they are negatively associated with 100% foreign ownership, possibly because the marginal costs of acquiring additional equity are growing with the size of the assets. The results are interpreted within the framework of the existing theory. In particular, following Demsetz and Lehn (1985) and Demsetz and Villalonga (2001) we argue that equity should not be treated as an exogenous variable. As for specific determinants of equity levels, we focus on informational asymmetries and (unobserved) ownership-specific characteristics of foreign investors and Hungarian investors

    Using mobile health technology to assess childhood autism in low-resource community settings in India: An innovation to address the detection gap

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    A diagnosis of autism typically depends on clinical assessments by highly trained professionals. This high resource demand poses a challenge in low-resource settings. Digital assessment of neurodevelopmental symptoms by non-specialists provides a potential avenue to address this challenge. This cross-sectional case-control field study establishes proof of principle for such a digital assessment. We developed and tested an app, START, that can be administered by non-specialists to assess autism phenotypic domains (social, sensory, motor) through child performance and parent reports. N = 131 children (2–7 years old; 48 autistic, 43 intellectually disabled and 40 non-autistic typically developing) from low-resource settings in Delhi-NCR, India were assessed using START in home settings by non-specialist health workers. The two groups of children with neurodevelopmental disorders manifested lower social preference, greater sensory interest and lower fine-motor accuracy compared to their typically developing counterparts. Parent report further distinguished autistic from non-autistic children. Machine-learning analysis combining all START-derived measures demonstrated 78% classification accuracy for the three groups. Qualitative analysis of the interviews with health workers and families of the participants demonstrated high acceptability and feasibility of the app. These results provide feasibility, acceptability and proof of principle for START, and demonstrate the potential of a scalable, mobile tool for assessing neurodevelopmental conditions in low-resource settings

    Scalable Transdiagnostic Early Assessment of Mental Health (STREAM): a study protocol

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    Introduction Early childhood development forms the foundations for functioning later in life. Thus, accurate monitoring of developmental trajectories is critical. However, such monitoring often relies on time-intensive assessments which necessitate administration by skilled professionals. This difficulty is exacerbated in low-resource settings where such professionals are predominantly concentrated in urban and often private clinics, making them inaccessible to many. This geographic and economic inaccessibility contributes to a significant ‘detection gap’ where many children who might benefit from support remain undetected. The Scalable Transdiagnostic Early Assessment of Mental Health (STREAM) project aims to bridge this gap by developing an open-source, scalable, tablet-based platform administered by non-specialist workers to assess motor, social and cognitive developmental status. The goal is to deploy STREAM through public health initiatives, maximising opportunities for effective early interventions. Methods and analysis The STREAM project will enrol and assess 4000 children aged 0–6 years from Malawi (n=2000) and India (n=2000). It integrates three established developmental assessment tools measuring motor, social and cognitive functioning using gamified tasks, observation checklists, parent-report and audio-video recordings. Domain scores for motor, social and cognitive functioning will be developed and assessed for their validity and reliability. These domain scores will then be used to construct age-adjusted developmental reference curves. Ethics and dissemination Ethical approval has been obtained from local review boards at each site (India: Sangath Institutional Review Board; All India Institute of Medical Science (AIIMS) Ethics Committee; Indian Council of Medical Research—Health Ministry Screening Committee; Malawi: College of Medicine Research and Ethics Committee; Malawi Ministry of Health—Blantyre District Health Office). The study adheres to Good Clinical Practice standards and the ethical guidelines of the 6th (2008) Declaration of Helsinki. Findings from STREAM will be disseminated to participating families, healthcare professionals, policymakers, educators and researchers, at local, national and international levels through meetings, academic journals and conferences

    Ownership identity, strategy and performance:business group affiliates versus independent firms in India

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    We consider whether the impact of entrepreneurial orientation on business performance is moderated by the company affiliation with business groups. Within business groups, we explore the trade-off between inter-firm insurance that enables risk-taking, and inefficient resource allocation. Risk-taking in group affiliated firms leads to higher performance, compared to independent firms, but the impact of proactivity is attenuated. Utilizing Indian data, we show that risk-taking may undermine rather than improve business performance, but this effect is not present in business groups. Proactivity enhances performance, but less so in business groups. Firms can also enhance performance by technological knowledge acquisition, but these effects are not significantly different for various ownership categories
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