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Effects of ethical congruence on person-organization fit and employee attitudes
By differentiating between the definitions of values and ethics, as well as contrasting value congruence with ethical congruence, this research aims to gain a greater understanding of person-organization fit
THE TIDELANDS OIL CONTROVERSY - A LEGAL AND HISTORICAL ANALYSIS, by Ernest R. Bartley. University of Texas Press, Austin, 1953. Pp. x, 312. $5.00.
On the Lichnerowicz conjecture for CR manifolds with mixed signature
We construct examples of nondegenerate CR manifolds with Levi form of
signature , , which are compact, not locally CR flat, and
admit essential CR vector fields. We also construct an example of a noncompact
nondegenerate CR manifold with signature which is not locally CR flat
and admits an essential CR vector fields. These provide counterexamples to the
analogue of the Lichnerowicz conjecture for CR manifolds with mixed signature.Comment: 7 page
Effect of butanol fraction from Cassia tora L. seeds on glycemic control and insulin secretion in diabetic rats
Cassia tora L. seeds have previously been reported to reduce blood glucose level in human and animals with diabetes. In the present study, the effects of Cassia tora L. seed butanol fraction (CATO) were studied on postprandial glucose control and insulin secretion from the pancreas of the normal and diabetic rats. Diabetes was induced by an i.p. injection of Streptozotocin (55 mg/kg BW) into the male Sprague-Dawley rats. The postprandial glucose control was monitored during a 240 min-period using a maltose loading test. In normal rats, rats fed CATO (20 mg/100 g BW/d) showed lower postprandial glucose levels in all the levels from 30 min up to 180 min than those in the control rats without CATO (p<0.05). In diabetic rats, those levels in the CATO group seemed to be lower during the 30~180 min, but only glucose level at 30 min showed significant difference compared to that in the control group. Moreover, CATO delayed the peak time of the glucose rise in both normal and diabetic rats in the glucose curves. On the other hand, when CATO was administered orally to the diabetic rats for 5 days, 12 hr fasting serum glucose level was decreased in the diabetic rats (p<0.05). Degree of a decrease in 12 hr fasting serum insulin levels was significantly less in the diabetic CATO rats as compared to diabetic control rats. On the last day of feeding, β cells of the pancreas were stimulated by 200 mg/dL glucose through a 40 min-pancreas perfusion. Amounts of the insulin secreted from the pancreas during the first phase (11~20 min) and the second phase (21~40 min) in the CATO fed diabetic rats were significantly greater than those in the diabetic control group (p<0.05). These findings indicated that constituents of Cassia tora L. seeds have beneficial effect on postprandial blood glucose control which may be partially mediated by stimulated insulin secretion from the pancreas of the diabetic rats
Constituting We the People
We study roles of the thermosphere and exosphere on the Martian ionospheric
structure and ion escape rates in the process of the solar wind-Mars
interaction. We employ a four-species multifluid MHD (MF-MHD) model to simulate
the Martian ionosphere and magnetosphere. The thermosphere background is
taken from the Mars Global Ionosphere Thermosphere Model (M-GITM) and the
oxygen exosphere is adopted from the Mars exosphere Monte Carlo model -
Adaptive Mesh Particle Simulator (AMPS). A total of four cases with the
combination of 1D (globally averaged) and 3D thermospheres and exospheres are
studied.
The ion escape rates calculated by adopting 1D and 3D atmospheres are
similar; however, the latter are required to adequately reproduce MAVEN
ionospheric observations. In addition, our simulations show that the 3D hot
oxygen corona plays an important role in preventing planetary molecular ions
(O and CO) escaping from Mars, mainly resulting from the mass
loading of the high-altitude exospheric O ions. The thermospheric
oxygen atom, however, is demonstrated to be the primary neutral source for
O ion escape during the relatively weak solar cycle 24.Comment: 21 pages, 10 figures, 4 tables, accepted for publication in Journal
of Geophysical Research-Space Physic
Using Underapproximations for Sparse Nonnegative Matrix Factorization
Nonnegative Matrix Factorization consists in (approximately) factorizing a
nonnegative data matrix by the product of two low-rank nonnegative matrices. It
has been successfully applied as a data analysis technique in numerous domains,
e.g., text mining, image processing, microarray data analysis, collaborative
filtering, etc.
We introduce a novel approach to solve NMF problems, based on the use of an
underapproximation technique, and show its effectiveness to obtain sparse
solutions. This approach, based on Lagrangian relaxation, allows the resolution
of NMF problems in a recursive fashion. We also prove that the
underapproximation problem is NP-hard for any fixed factorization rank, using a
reduction of the maximum edge biclique problem in bipartite graphs.
We test two variants of our underapproximation approach on several standard
image datasets and show that they provide sparse part-based representations
with low reconstruction error. Our results are comparable and sometimes
superior to those obtained by two standard Sparse Nonnegative Matrix
Factorization techniques.Comment: Version 2 removed the section about convex reformulations, which was
not central to the development of our main results; added material to the
introduction; added a review of previous related work (section 2.3);
completely rewritten the last part (section 4) to provide extensive numerical
results supporting our claims. Accepted in J. of Pattern Recognitio
Using the Sirocco File System for high-bandwidth checkpoints.
The Sirocco File System, a file system for exascale under active development, is designed to allow the storage software to maximize quality of service through increased flexibility and local decision-making. By allowing the storage system to manage a range of storage targets that have varying speeds and capacities, the system can increase the speed and surety of storage to the application. We instrument CTH to use a group of RAM-based Sirocco storage servers allocated within the job as a high-performance storage tier to accept checkpoints, allowing computation to potentially continue asynchronously of checkpoint migration to slower, more permanent storage. The result is a 10-60x speedup in constructing and moving checkpoint data from the compute nodes. This demonstration of early Sirocco functionality shows a significant benefit for a real I/O workload, checkpointing, in a real application, CTH. By running Sirocco storage servers within a job as RAM-only stores, CTH was able to store checkpoints 10-60x faster than storing to PanFS, allowing the job to continue computing sooner. While this prototype did not include automatic data migration, the checkpoint was available to be pushed or pulled to disk-based storage as needed after the compute nodes continued computing. Future developments include the ability to dynamically spawn Sirocco nodes to absorb checkpoints, expanding this mechanism to other fast tiers of storage like flash memory, and sharing of dynamic Sirocco nodes between multiple jobs as needed
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