105 research outputs found

    Expatriation Practices in the Global Business Environment

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    Globalisation, characterised by advanced communication and distribution technologies, e-commerce, new strategic alliances, organisational restructuring and the 'internationalisation' of operations, demands new approaches to international human resource management. The transformation from international to global business necessitates a parallel paradigm shift in international human resource management theory, especially as it applies to the management of expatriates in the information era.Earlier assumptions and perspectives will need to be replaced by broader definitions and conceptualisations. This paper examines the foundations of earlier views of expatriate management, and suggests ways in which a new paradigm, more reflective of globalisation, might be developed

    Radiation-Tolerant, GaN-based Point of Load Converters for Small Spacecraft Missions

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    As computational loads for spacecraft continue to grow, the requirements levied on power-conversion electronics have become increasingly demanding. Designing for compute-intensive processing capabilities in the CubeSat form-factor further encourages the use of lightweight, compact, and efficient power-conversion electronics. However, the radiation-tolerant and radiation-hardened point-of-load converters available from existing vendors are large, expensive, and inefficient relative to their commercial counterparts. To alleviate this disparity, this paper presents the design, development, and testing of three radiation-tolerant, point-of-load (PoL) converters using Gallium Nitride (GaN) High-Electron Mobility Transistors (HEMT) and commercial controllers to enable the success of future small-satellite missions

    Dynamics of global forest area: Results from the FAO Global Forest Resources Assessment 2015

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    The area of land covered by forest and trees is an important indicator of environmental condition. This study presents and analyses results from the Global Forest Resources Assessment 2015 (FRA 2015) of the Food and Agriculture Organization of the United Nations. FRA 2015 was based on responses to surveys by individual countries using a common reporting framework, agreed definitions and reporting standards. Results indicated that total forest area declined by 3%, from 4128 M ha in 1990 to 3999 M ha in 2015. The annual rate of net forest loss halved from 7.3 M ha y−1 in the 1990s to 3.3 M ha y−1 between 2010 and 2015. Natural forest area declined from 3961 M ha to 3721 M ha between 1990 and 2015, while planted forest (including rubber plantations) increased from 168 M ha to 278 M ha. From 2010 to 2015, tropical forest area declined at a rate of 5.5 M ha y−1 – only 58% of the rate in the 1990s – while temperate forest area expanded at a rate of 2.2 M ha y−1. Boreal and sub-tropical forest areas showed little net change. Forest area expanded in Europe, North America, the Caribbean, East Asia, and Western-Central Asia, but declined in Central America, South America, South and Southeast Asia and all three regions in Africa. Analysis indicates that, between 1990 and 2015, 13 tropical countries may have either passed through their forest transitions from net forest loss to net forest expansion, or continued along the path of forest expansion that follows these transitions. Comparing FRA 2015 statistics with the findings of global and pan-tropical remote-sensing forest area surveys was challenging, due to differences in assessment periods, the definitions of forest and remote sensing methods. More investment in national and global forest monitoring is needed to provide better support for international initiatives to increase sustainable forest management and reduce forest loss, particularly in tropical countries

    Digoxin net secretory transport in bronchial epithelial cell layers is not exclusively mediated by P-glycoprotein/MDR1

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    Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-No Derivative Works License, which permits non-commercial use, distribution, and reproduction in any medium, provided the original author and source are creditedThe impact of P-glycoprotein (MDR1, ABCB1) on drug disposition in the lungs as well as its presence and activity in in vitro respiratory drug absorption models remain controversial to date. Hence, we characterised MDR1 expression and the bidirectional transport of the common MDR1 probe 3H-digoxin in air-liquid interfaced (ALI) layers of normal human bronchial epithelial (NHBE) cells and of the Calu-3 bronchial epithelial cell line at different passage numbers. Madin-Darby Canine Kidney (MDCKII) cells transfected with the human MDR1 were used as positive controls. 3H-digoxin efflux ratio (ER) was low and highly variable in NHBE layers. In contrast, ER=11.4 or 3.0 was measured in Calu-3 layers at a low or high passage number, respectively. These were, however, in contradiction with increased MDR1 protein levels observed upon passaging. Furthermore, ATP depletion and the two MDR1 inhibitory antibodies MRK16 and UIC2 had no or only a marginal impact on 3H-digoxin net secretory transport in the cell line. Our data do not support an exclusive role of MDR1 in 3H-digoxin apparent efflux in ALI Calu-3 layers and suggest the participation of an ATP-independent carrier. Identification of this transporter might provide a better understanding of drug distribution in the lungs.Peer reviewe

    A Randomized Controlled Multicenter US Food and Drug Administration Trial of the Safety and Efficacy of the Minerva Endometrial Ablation System: One-Year Follow-Up Results

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    AbstractStudy ObjectiveTo assess the safety and effectiveness of the Minerva Endometrial Ablation System for the treatment of heavy menstrual bleeding in premenopausal women.DesignMulticenter, randomized, controlled, international study (Canadian Task Force classification I).SettingThirteen academic and private medical centers.PatientsPremenopausal women (n = 153) suffering from heavy menstrual bleeding (PALM-COEIN: E, O).InterventionPatients were treated using the Minerva Endometrial Ablation System or rollerball ablation.Measurements and Main ResultsAt 1-year post-treatment, study success (alkaline hematin ≤80 mL) was observed in 93.1% of Minerva subjects and 80.4% of rollerball subjects with amenorrhea reported by 71.6% and 49% of subjects, respectively. The mean procedure times were 3.1 minutes for Minerva and 17.2 minutes for rollerball. There were no intraoperative adverse events and/or complications reported.ConclusionThe results of this multicenter randomized controlled trial demonstrate that at the 12-month follow-up, the Minerva procedure produces statistically significantly higher rates of success, amenorrhea, and patient satisfaction as well as a shorter procedure time when compared with the historic criterion standard of rollerball ablation. Safety results were excellent and similar for both procedures

    Co-directional replication-transcription conflicts lead to replication restart

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    August 24, 2011Head-on encounters between the replication and transcription machineries on the lagging DNA strand can lead to replication fork arrest and genomic instability1, 2. To avoid head-on encounters, most genes, especially essential and highly transcribed genes, are encoded on the leading strand such that transcription and replication are co-directional. Virtually all bacteria have the highly expressed ribosomal RNA genes co-directional with replication3. In bacteria, co-directional encounters seem inevitable because the rate of replication is about 10–20-fold greater than the rate of transcription. However, these encounters are generally thought to be benign2, 4, 5, 6, 7, 8, 9. Biochemical analyses indicate that head-on encounters10 are more deleterious than co-directional encounters8 and that in both situations, replication resumes without the need for any auxiliary restart proteins, at least in vitro. Here we show that in vivo, co-directional transcription can disrupt replication, leading to the involvement of replication restart proteins. We found that highly transcribed rRNA genes are hotspots for co-directional conflicts between replication and transcription in rapidly growing Bacillus subtilis cells. We observed a transcription-dependent increase in association of the replicative helicase and replication restart proteins where head-on and co-directional conflicts occur. Our results indicate that there are co-directional conflicts between replication and transcription in vivo. Furthermore, in contrast to the findings in vitro, the replication restart machinery is involved in vivo in resolving potentially deleterious encounters due to head-on and co-directional conflicts. These conflicts probably occur in many organisms and at many chromosomal locations and help to explain the presence of important auxiliary proteins involved in replication restart and in helping to clear a path along the DNA for the replisome.Biotechnology and Biological Sciences Research Council (Great Britain) (Grant BB/E006450/1)Wellcome Trust (London, England) (Grant 091968/Z/10/Z)National Institutes of Health (U.S.) (Grant GM41934)National Institutes of Health (U.S.) (Postdoctoral Fellowship GM093408)Biotechnology and Biological Sciences Research Council (Great Britain) (Sabbatical Visit

    When simple sequence comparison fails: the cryptic case of the shared domains of the bacterial replication initiation proteins DnaB and DnaD

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    DnaD and DnaB are essential DNA-replication-initiation proteins in low-G+C content Gram-positive bacteria. Here we use sensitive Hidden Markov Model-based techniques to show that the DnaB and DnaD proteins share a common structure that is evident across all their structural domains, termed DDBH1 and DDBH2 (DnaD DnaB Homology 1 and 2). Despite strong sequence divergence, many of the DNA-binding and oligomerization properties of these domains have been conserved. Although eluding simple sequence comparisons, the DDBH2 domains share the only strong sequence motif; an extremely highly conserved YxxxIxxxW sequence that contributes to DNA binding. Sequence alignments of DnaD alone fail to identify another key part of the DNA-binding module, since it includes a poorly conserved sequence, a solvent-exposed and somewhat unstable helix and a mobile segment. We show by NMR, in vitro mutagenesis and in vivo complementation experiments that the DNA-binding module of Bacillus subtilis DnaD comprises the YxxxIxxxW motif, the unstable helix and a portion of the mobile region, the latter two being essential for viability. These structural insights lead us to a re-evaluation of the oligomerization and DNA-binding properties of the DnaD and DnaB proteins

    Creative learning environments in education-A systematic literature review

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    This paper reports on a systematic review of 210 pieces of educational research, policy and professional literature relating to creative environments for learning in schools, commissioned by Learning and Teaching Scotland (LTS). Despite the volume of academic literature in this field, the team of six reviewers found comparatively few empirical studies published in the period 2005–2011 providing findings addressing the review objectives. There was, however a reasonable weight of research evidence to support the importance of the following factors in supporting creative skills development in children and young people: flexible use of space and time; availability of appropriate materials; working outside the classroom/school; ‘playful’ or ‘games-bases’ approaches with a degree of learner autonomy; respectful relationships between teachers and learners; opportunities for peer collaboration; partnerships with outside agencies; awareness of learners’ needs; and non-prescriptive planning. The review also found evidence for impact of creative environments on pupil attainment and the development of teacher professionalism. LTS intend to use the review as a basis for recommendations to Scottish schools in promoting creativity within Curriculum for Excellence. However, the findings of the review and methodological gaps in the reviewed studies have implications for policy, practice and research internationally

    Development and Reporting of Prediction Models: Guidance for Authors From Editors of Respiratory, Sleep, and Critical Care Journals

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    Prediction models aim to use available data to predict a health state or outcome that has not yet been observed. Prediction is primarily relevant to clinical practice, but is also used in research, and administration. While prediction modeling involves estimating the relationship between patient factors and outcomes, it is distinct from casual inference. Prediction modeling thus requires unique considerations for development, validation, and updating. This document represents an effort from editors at 31 respiratory, sleep, and critical care medicine journals to consolidate contemporary best practices and recommendations related to prediction study design, conduct, and reporting. Herein, we address issues commonly encountered in submissions to our various journals. Key topics include considerations for selecting predictor variables, operationalizing variables, dealing with missing data, the importance of appropriate validation, model performance measures and their interpretation, and good reporting practices. Supplemental discussion covers emerging topics such as model fairness, competing risks, pitfalls of “modifiable risk factors”, measurement error, and risk for bias. This guidance is not meant to be overly prescriptive; we acknowledge that every study is different, and no set of rules will fit all cases. Additional best practices can be found in the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guidelines, to which we refer readers for further details
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