1,640 research outputs found
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Small and Medium sized Enterprises’ Collaborative Buyer-Supplier Relationships: Boundary Spanning Individual Perspectives
Boundary-spanning individuals (BSIs) play a critical role in supply chain management, especially in small and medium sized enterprises (SMEs) where interactions with buyers and suppliers can depend heavily on just a few individuals. This study, utilizing data from Korean manufacturing-sector SMEs, explores whether cooperative social value orientations of SMEs’ BSIs influence the effects of collaborative buyer-supplier initiatives. The results suggested that the performance implication of decision-sharing initiative increases when BSIs have a high level of cooperative social value orientation. However, it also negatively moderates the relationship between risk/benefit sharing (involving financial losses or gains) and performance suggesting possible negative side-effects. However, we found that such orientation also negatively moderates the relationship between risk/benefit sharing (involving direct financial losses or gains) and relationship performance suggesting possible negative side-effects
Planck Oscillators in the Background Dark Energy
We consider a model for an underpinning of the universe: there are
oscillators at the Planck scale in the background dark energy. Starting from a
coherent array of such oscillators it is possible to get a description from
elementary particles to Black Holes including the usual Hawking-Beckenstein
theory. There is also a description of Gravitation in the above model which
points to a unified description with electromagnetism.Comment: 18 pages latex; talk at the Max Born Symposium 2009, Wrocla
Vulnerability of protoxylem and metaxylem vessels to embolisms and radial refilling in a vascular bundle of maize leaves
Regulation of water flow in an interconnected xylem vessel network enables plants to survive despite challenging environment changes that can cause xylem embolism. In this study, vulnerability to embolisms of xylem vessels and their water-refilling patterns in vascular bundles of maize leaves were experimentally investigated by employing synchrotron X-ray micro-imaging technique. A vascular bundle in maize consisted of a protoxylem vessel with helical thickenings between two metaxylem vessels with single perforation plates and nonuniformly distributed pits. When embolism was artificially induced in excised maize leaves by exposing them to air, protoxylem vessels became less vulnerable to dehydration compared to metaxylem vessels. After supplying water into the embolized vascular bundles, when water-refilling process stopped at the perforation plates in metaxylem vessels, discontinuous radial water influx occurred surprisingly in the adjacent protoxylem vessels. Alternating water refilling pattern in protoxylem and metaxylem vessels exhibited probable correlation between the incidence location and time of water refilling and the structural properties of xylem vessels. These results imply that the maintenance of water transport and modulation of water refilling are affected by hydrodynamic roles of perforation plates and radial connectivity in a xylem vascular bundle network.113Ysciescopu
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Supply chain information in analyst reports on publicly traded companies
Analyst reports are an important source of secondary data on companies for understanding a company's performance in the recent past and for getting guidance on its future performance. We therefore analyzed the text of 1028 equity analyst reports of 145 Fortune 500 Global companies (not including services sectors like IT or banking) published between 2009 and 2011 for supply chain related information. We found that nearly three-fifths of these reports contained supply chain information pertaining to inbound, process or outbound aspects of the supply chain of the company. At the report level, there are significant industry effects for supply chain related content in analyst reports. On the other hand, aggregating information at the company level, it appears that analysts focus on a particular supply chain aspect for a company as well as its sector. Furthermore, logistic regression analysis suggests a link between the supply chain information provided when this is positive in orientation and the buy/sell/hold recommendation of the analyst regarding the company's stock
Investigating the Fair Treatment of Suppliers and its Trust Fostering Role and Performance Benefits
An increasing number of companies have begun to make efforts to treat their suppliers fairly as a part of wider corporate social responsibility (CSR) initiatives. Few studies, however, have investigated the performance implications of such efforts for buying firms. This paper uses both organisational climate theory and social exchange theory to investigate (1) if buying firms' efforts in the form of a code of conduct for its procurement practitioners pay off, and (2) its mechanisms from the perspectives of procurement practitioners. We use a multi-method approach, combining analysis of survey data complemented by results from a behavioural experiment. First, survey data were gathered from 327 Korean manufacturing companies and analysed using structural equation modelling. Second, the findings were complemented by a behavioural experiment involving 120 subjects. The results support the positive performance implications of fair supplier treatment in the form of codes of conduct for procurement practitioners. The paper also offers insights into how such efforts benefit buying firms, which is due to the trust in the buyer-supplier relationship fostered by the resulting ethical behaviours of procurement practitioners
Revisiting Zitterbewegung
The Dirac wave equation for the electron soon lead to the recognition of the
Zitterbewegung. This was studied both by Schrodinger and Dirac. Later there
were further elegant and sometimes dissenting insights, from different authors.
We briefly review some of these developments. However in more recent times with
dark energy and noncommutative spacetime coming to centre stage, the earlier
studies of Zitterbewegung become questionable.Comment: 14 pages; late
Nearly Perfect Durable Superhydrophobic Surfaces Fabricated by a Simple One-Step Plasma Treatment
Fabrication of superhydrophobic surfaces is an area of great interest because it can be applicable to various engineering fields. A simple, safe and inexpensive fabrication process is required to fabricate applicable superhydrophobic surfaces. In this study, we developed a facile fabrication method of nearly perfect superhydrophobic surfaces through plasma treatment with argon and oxygen gases. A polytetrafluoroethylene (PTFE) sheet was selected as a substrate material. We optimized the fabrication parameters to produce superhydrophobic surfaces of superior performance using the Taguchi method. The contact angle of the pristine PTFE surface is approximately 111.0�� �� 2.4��, with a sliding angle of 12.3�� �� 6.4��. After the plasma treatment, nano-sized spherical tips, which looked like crown-structures, were created. This PTFE sheet exhibits the maximum contact angle of 178.9��, with a sliding angle less than 1��. As a result, this superhydrophobic surface requires a small external force to detach water droplets dripped on the surface. The contact angle of the fabricated superhydrophobic surface is almost retained, even after performing an air-aging test for 80 days and a droplet impacting test for 6 h. This fabrication method can provide superb superhydrophobic surface using simple one-step plasma etching. ? 2017 The Author(s).114Ysciescopu
Molecular and clinical characterization of a claudin-low subtype of gastric cancer
Purpose Claudin-low molecular subtypes have been identified in breast and bladder cancers and are characterized by low expression of claudins, enrichment for epithelial-to-mesenchymal transition (EMT), and tumor-initiating cell (TIC) features. We evaluated whether the claudin-low subtype also exists in gastric cancer. Materials and Methods Four hundred fifteen tumors from The Cancer Genome Atlas (TCGA) gastric cancer mRNA data set were clustered on the claudin, EMT, and TIC gene sets to identify claudin-low tumors. We derived a 24-gene predictor that classifies gastric cancer into claudin-low and non-claudin-low subtypes. This predictor was validated with the Asian Cancer Research Group(ACRG)data set. We characterized molecular and clinical features of claudin-low tumors. Results We identified 46 tumors that had consensus enrichment for claudin-low features in TCGA data set. Claudin-low tumors were most commonly diffuse histologic type (82%) and originally classified as TCGA genomically stable(GS)subtype (78%). Compared with GS subtype, claudin-low subtype had significant activation in Rho family of GTPases signaling, which appears to play a key role in its EMT and TIC properties. In the ACRG data set, 28 of 300 samples were classified as claudin-low tumors by the 24-gene predictor and were phenotypically similar to the initially derived claudin-low tumors. Clinically, claudin-low subtype had the worst overall survival. Of note, the hazard ratios that compared claudin-low versus GS subtype were 2.10 (95% CI, 1.07 to 4.11) in TCGA and 2.32 (95% CI, 1.18 to 4.55) in the ACRG cohorts, with adjustment for age and pathologic stage. Conclusion We identified a gastric claudin-low subtype that carries a poor prognosis likely related to therapeutic resistance as a result of its EMT and TIC phenotypes
Big, Fast Vortices in the d-RVB theory of High Temperature Superconductivity
The effect of proximity to a Mott insulating phase on the superflow
properties of a d-wave superconductor is studied using the slave boson-U(1)
gauge theory model. The model has two limits corresponding to superconductivity
emerging either out of a 'renormalized fermi liquid' or out of a
non-fermi-liquid regime. Three crucial physical parameters are identified: the
size of the vortex \textit{as determined from the supercurrent it induces;} the
coupling of the superflow to the quasiparticles and the 'nondissipative time
derivative' term. As the Mott phase is approached, the core size as defined
from the supercurrent diverges, the coupling between superflow and
quasiparticles vanishes, and the magnitude of the nondissipative time
derivative dramatically increases. The dissipation due to a moving vortex is
found to vary as the third power of the doping. The upper critical field and
the size of the critical regime in which paraconductivity may be observed are
estimated, and found to be controlled by the supercurrent length scale
Detailed Examination of Transport Coefficients in Cubic-Plus-Quartic Oscillator Chains
We examine the thermal conductivity and bulk viscosity of a one-dimensional
(1D) chain of particles with cubic-plus-quartic interparticle potentials and no
on-site potentials. This system is equivalent to the FPU-alpha beta system in a
subset of its parameter space. We identify three distinct frequency regimes
which we call the hydrodynamic regime, the perturbative regime and the
collisionless regime. In the lowest frequency regime (the hydrodynamic regime)
heat is transported ballistically by long wavelength sound modes. The model
that we use to describe this behaviour predicts that as the frequency goes to
zero the frequency dependent bulk viscosity and the frequency dependent thermal
conductivity should diverge with the same power law dependence on frequency.
Thus, we can define the bulk Prandtl number as the ratio of the bulk viscosity
to the thermal conductivity (with suitable prefactors to render it
dimensionless). This dimensionless ratio should approach a constant value as
frequency goes to zero. We use mode-coupling theory to predict the zero
frequency limit. Values of the bulk Prandtl number from simulations are in
agreement with these predictions over a wide range of system parameters. In the
middle frequency regime, which we call the perturbative regime, heat is
transported by sound modes which are damped by four-phonon processes. We call
the highest frequency regime the collisionless regime since at these
frequencies the observing times are much shorter than the characteristic
relaxation times of phonons. The perturbative and collisionless regimes are
discussed in detail in the appendices.Comment: Latex with references in .bib file. 36 pages, 8 figures. Submitted to
J. Stat. Phys. on Sept. 2
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