1,791 research outputs found
Collective pinning of imperfect vortex lattices by material line defects in extreme type-II superconductors
The critical current density shown by a superconductor at the extreme type-II
limit is predicted to follow an inverse square-root power law with external
magnetic field if the vortex lattice is weakly pinned by material line defects.
It acquires an additional inverse dependence with thickness along the line
direction once pinning of the interstitial vortex lines by material point
defects is included. Moderate quantitative agreement with the critical current
density shown by second-generation wires of high-temperature superconductors in
kG magnetic fields is achieved at liquid-nitrogen temperature.Comment: 10 pages, 3 figures, 2 tables. To appear in Physical Review
Contamination of spacecraft by recontact of dumped liquids
Liquids partially freeze when dumped from spacecraft producing particles which are released into free space at various velocities. Recontact of these particles with the spacecraft is possible for specific particle sizes and velocities and, therefore, can become contamination for experiments within the spacecraft or released experiments as a result of waste and potable water dumped from Space Shuttle. An examination of dump characteristics was conducted on STS-29 using both on-board video records and ground based measurements. A preliminary analysis of data from this flight indicates particle velocities are in the range of 30 to 75 ft/sec and recontact is possible for limited particle sizes
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Alsophis rufiventris
Number of Pages: 4Integrative BiologyGeological Science
People management and innovation in emerging market multinationals
As the internationalization process dictates the existence of cross-country networks it is essential to explore avenues that allow emerging market multinationals (EMNCs) to share and receive knowledge that can benefit them locally and globally. In this manuscript we explore this conundrum by addressing the significance of creating a global mindset in individuals and across the MNC. In the manuscript we articulate the mechanisms that influence global managers’ abilities to engage effectively with other global managers across borders. We argued that global managers engage in reciprocal learning processes to obtain new, innovative knowledge about other countries’ environments and business practices. We furthermore suggest that the effectiveness of new knowledge creation is dependent upon the appropriate input, throughput, and output competencies of those involved in the reciprocal learning process. Proper people management plays a crucial role in fostering an environment where employees’ commitment will lead to organisational innovation. Propositions foreshadowing in the new, innovative knowledge creation process across cultural and personal levels are articulated
Modified Appleby Procedure with Arterial Reconstruction for Locally Advanced Pancreatic Adenocarcinoma: A Literature Review and Report of Three Unusual Cases.
BACKGROUND: Pancreatic body and tail ductal adenocarcinomas are often diagnosed with local vascular invasion of the celiac axis (CA) and its various branches. With such involvement, these tumors have traditionally been considered unresectable. The modified Appleby procedure allows for margin negative resection of some such locally advanced tumors. This procedure involves distal pancreatectomy with en bloc splenectomy and CA resection and relies on the presence of collateral arterial circulation via an intact pancreaticoduodenal arcade and the gastroduodenal artery to maintain prograde hepatic arterial perfusion. When the resultant collateral circulation is inadequate to provide sufficient hepatic and gastric arterial inflow, arterial reconstruction (AR) is necessary to supercharge the inflow. Herein, we review all reported cases of AR with modified Appleby procedures that we have identified in the literature, and we report our experience of three recent cases with arterial reconstruction including two cases with arterial bypasses not requiring interposition grafting.
METHODS: Perioperative and oncologic outcomes from our Institutional Review Board-approved database of pancreatic resections at the Thomas Jefferson University were reviewed. Additionally, PubMed search for cases of distal or total pancreatectomy with celiac axis resection and concurrent AR was performed.
RESULTS: From the literature, 12 reports involving 28 patients were identified of distal and total pancreatectomy with AR after CA resection. The most common AR in the literature, performed in 12 patients, was a bypass from the aorta to the common hepatic artery (CHA) using a variety of interposition conduits. In our institutional experience, patient #1 had a primary side-to-end aorto-CHA bypass, patient #2 had a primary end-to-end bypass of the transected distal CHA to the left gastric artery in the setting a replaced left hepatic artery, and patient #3 required an aortic to proper hepatic artery bypass with saphenous vein graft and portal venous reconstruction. All patients recovered from their operations without ischemic complications, and they are currently 16, 15, and 13 months post-op, respectively.
CONCLUSIONS: The criteria for resectability in patients with locally advanced pancreatic body and tail neoplasms are expanding due to increasing experience with AR in the setting of the modified Appleby procedure. When performing AR, primary arterial re-anastomosis may be considered preferable to interposition grafting as it decreases the potential for the infectious and thrombotic complications associated with conduits and it reduces the number of vascular anastomoses from two to one. Consideration must also be given to normal variant anatomy of the hepatic circulation during operative planning as the origin of the left gastric artery is resected with the CA. The modified Appleby procedure with AR, when used in appropriately selected patients, offers the potential for safe, margin negative resection of locally advanced pancreatic body and tail tumors
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Employee performance management: charting the field from 1998 to 2018
Purpose: The purpose of this paper is to study the development and consider the future of one of the most controversial areas of human resource development – employee performance management (PM).
Design/methodology/approach: Through bibliometrics, a multiple correspondence analysis identifies the main research directions of PM studies and provides a map of descriptors and a list of authors, along with a framework to track PM literature over 20 years (1998–2018).
Findings: Scholars have attempted to address some of the questions raised by earlier researchers. However, critical questions remain unanswered, and there is increasing dissatisfaction with the process. The most glaring yet unaddressed problem with PM is poor employee acceptability of the process.
Practical implications: If the research gaps are addressed, the lack of acceptability of the PM could be resolved and more effectively managed in the future.
Originality/value: The study particularly addresses poor employee “acceptability” of the PM process, a subject that has received limited attention by scholars
Inferring Species Trees Directly from Biallelic Genetic Markers: Bypassing Gene Trees in a Full Coalescent Analysis
The multi-species coalescent provides an elegant theoretical framework for
estimating species trees and species demographics from genetic markers.
Practical applications of the multi-species coalescent model are, however,
limited by the need to integrate or sample over all gene trees possible for
each genetic marker. Here we describe a polynomial-time algorithm that computes
the likelihood of a species tree directly from the markers under a finite-sites
model of mutation, effectively integrating over all possible gene trees. The
method applies to independent (unlinked) biallelic markers such as well-spaced
single nucleotide polymorphisms (SNPs), and we have implemented it in SNAPP, a
Markov chain Monte-Carlo sampler for inferring species trees, divergence dates,
and population sizes. We report results from simulation experiments and from an
analysis of 1997 amplified fragment length polymorphism (AFLP) loci in 69
individuals sampled from six species of {\em Ourisia} (New Zealand native
foxglove)
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An analysis of globalisation in international business research 1993–2018: rise of the sceptics
Purpose: The aim of this article is to provide an analysis of the current state of international business research on the topic of globalisation and to guide researchers who are new to international business research as to which journals and authors to consult when studying this phenomenon.
Design: The article presents a bibliometric analysis using the Web of Science database. A multiple correspondence analysis provides a map of keywords and authors, as well as a framework for tracking globalisation literature over the 26 years, 1993–2018.
Findings: The findings identify several fundamental themes and significant gaps in the extant literature; the most alarming gap centres around the effect of globalisation on social issues and, consequently, the rise of the anti-globalisation crusaders.
Practical Implications: A distinctive contribution of this study is that it investigates the intersection between globalisation and international business. We seek to expose the intellectual structure of globalisation research, identify existing and emerging themes of globalisation research, and discuss future research streams.
Social Implications: Our findings show the rise of the globalisation sceptic and reveal the mounting concerns regarding the unequal benefits of globalisation.
Originality/Value: There are two key benefits of this review. First, we identify a swing from an alignment of globalisation with the transformationalist viewpoint to rising support in favour of the sceptical viewpoint – a fact that is fuelling the anti-globalisation crusaders. Second, the review has the potential to guide scholars on precisely what needs to be explored in IB globalisation research
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