6,140 research outputs found
Quasi multipartite entanglement measure based on quadratic functions
We develop a new entanglement measure by extending Jaeger's Minkowskian norm
entanglement measure. This measure can be applied to a much wider class of
multipartite mixed states, although still "quasi" in the sense that it is still
incapable of dividing precisely the sets of all separable and entangled states.
As a quadratic scalar function of the system density matrix, the quasi measure
can be easily expressed in terms of the so-called coherence vector of the
system density matrix, by which we show the basic properties of the quasi
measure including (1) zero-entanglement for all separable states, (2)
invariance under local unitary operations, and (3) non-increasing under local
POVM (positive operator-valued measure) measurements. These results open up
perspectives in further studies of dynamical problems in open systems,
especially the dynamic evolution of entanglement, and the entanglement
preservation against the environment-induced decoherence effects.Comment: 10pages,1 figur
Effects of Short-Term Training of Community-Dwelling Elderly with Modular Interactive Tiles
Objective: The objective of this study is to test for the increased mobility, agility, balancing, and general fitness of community-dwelling elderly individuals as a result of short-term training involving playing with modular interactive tiles (Entertainment Robotics, Odense, Denmark) at two community activity centers for the elderly. Three different tests from the Senior Fitness Test were used in order to test a variety of health parameters of the community-dwelling elderly, including those parameters related to fall prevention. Materials and Methods: Eighteen community-dwelling elderly individuals (63â95 years of age; mean, 83.2 years of age) were assessed in one intervention group without the use of a control group. The intervention group performed nine group sessions (1â1.5 hours each) of playful training with the modular interactive tiles over a 12-week period in two community activity centers for the elderly. Data were collected using pre-tests and post-tests of the 6-Minute Walk Test (6MWT), the 8-foot Timed Up & Go Test (TUG), and the Chair-Stand Test (CS). Data were analyzed for statistically significant differences and increases of means. Results: The 6MWT, TUG, and CS measurements showed statistically significant differences and increases of means between the pre-tests and post-tests with the 6MWT (P<0.001) (means difference, 22.4 percent), TUG (P<0.001) (means difference, 15 percent), and CS (P<0.002) (means difference, 14 percent). Fifty-six percent of the elderly progressed from one health risk level to a better level, according to the three tests. Conclusions: Statistically significant increases in scores were found across all tests, suggesting an improvement of many different health parameters for the elderly. Well-established research has shown the relationship between such test scores and fall incidents, balancing, mobility, agility, etc. This significant improvement in the health status of the elderly is obtained in as few as nine training sessions over a 12-week period of âplayingâ exergames with the modular interactive tiles
Prognostic impact of matched preoperative plasma and serum VEGF in patients with primary colorectal carcinoma
In serum, the major part of vascular endothelial growth factor derives from in vitro degranulation of granulocytes and platelets. Therefore, plasma may be preferred for vascular endothelial growth factor measurements. However, which specimen is the best predictor of survival is still debated. The present study analyzed the prognostic value of matched preoperative serum and plasma vascular endothelial growth factor concentrations in patients with colorectal cancer. To establish the reference range among healthy people, vascular endothelial growth factor was analyzed in 50 matched EDTA-plasma and serum samples from healthy blood donors. Preoperatively, in 524 patients with colorectal cancer, matched plasma and serum vascular endothelial growth factor concentrations were analyzed. In the colorectal cancer patients, the median plasma vascular endothelial growth factor concentration (44âpgâmlâ1) was significantly (P=0.01) higher than the median plasma vascular endothelial growth factor concentration (30âpgâmlâ1) in the healthy blood donors. In serum, no significant (P=0.30) difference in the median vascular endothelial growth factor concentration was found between colorectal cancer patients (268âpgâmlâ1) and healthy blood donors (220âpgâmlâ1). The preoperative vascular endothelial growth factor concentrations were dichotomized by the 95th percentile of the healthy blood donors (plasma=112âpgâmlâ1, serum=533âpgâmlâ1). In univariate survival analyses, both high plasma vascular endothelial growth factor (>112âpgâmlâ1) and high serum vascular endothelial growth factor (>533âpgâmlâ1) predicted a reduced survival. In multivariate survival analyses, high serum vascular endothelial growth factor (>533âpgâmlâ1) independently predicted a reduced survival (HR=1.65, P=0.015), while high plasma vascular endothelial growth factor (>112âpgâmlâ1) did not (HR=1.27, P=0.23). This study indicates that preoperative serum vascular endothelial growth factor apparently is a better predictor of overall survival than the preoperative plasma vascular endothelial growth factor
Bone mineral content after renal transplantation
Forearm bone mineral content (BMC), as evaluated by photonabsorption densitometry, was measured in 28 cadaver kidney donor recipients who entered the study 8 weeks postoperatively and were followed up for 18 months. BMC decreased signifiantly (p<0.05) but marginally in placebo-treated patients (n=14) (initial BMC 1.09±0.25 g/cm; final BMC 1.05±0.24). Fourteen patients were prophylactically given 1,25(OH)2vitamin D3 in a dose which avoided hypercalcemia and hypercalciuria (sim0.25 ”g/day); under 1,25(OH)2 vitamin D3 prophylaxis a significant decrease of forearm BMC was observed no longer (initial BMC 0.94±0.21 g/cm; final BMC 0.95±0.21), but the difference between placebo and 1,25(OH)2 vitamin D3 narrowly missed statistical significance (p=0.066).
It is concluded that the decrease of forearm BMC is negligible in transplant recipients with low steroid regimens. The data suggest a trend for prophylaxis with 1,25(OH)2 vitamin D3 to slightly ameliorate forearm (cortical) BMC loss
Genome-Wide Survey of MicroRNA - Transcription Factor Feed-Forward Regulatory Circuits in Human
In this work, we describe a computational framework for the genome-wide
identification and characterization of mixed
transcriptional/post-transcriptional regulatory circuits in humans. We
concentrated in particular on feed-forward loops (FFL), in which a master
transcription factor regulates a microRNA, and together with it, a set of joint
target protein coding genes. The circuits were assembled with a two step
procedure. We first constructed separately the transcriptional and
post-transcriptional components of the human regulatory network by looking for
conserved over-represented motifs in human and mouse promoters, and 3'-UTRs.
Then, we combined the two subnetworks looking for mixed feed-forward regulatory
interactions, finding a total of 638 putative (merged) FFLs. In order to
investigate their biological relevance, we filtered these circuits using three
selection criteria: (I) GeneOntology enrichment among the joint targets of the
FFL, (II) independent computational evidence for the regulatory interactions of
the FFL, extracted from external databases, and (III) relevance of the FFL in
cancer. Most of the selected FFLs seem to be involved in various aspects of
organism development and differentiation. We finally discuss a few of the most
interesting cases in detail.Comment: 51 pages, 5 figures, 4 tables. Supporting information included.
Accepted for publication in Molecular BioSystem
On the infrared behaviour of 3d Chern-Simons theories in N=2 superspace
We discuss the problem of infrared divergences in the N=2 superspace approach
to classically marginal three-dimensional Chern-Simons-matter theories.
Considering the specific case of ABJM theory, we describe the origin of such
divergences and offer a prescription to eliminate them by introducing
non-trivial gauge-fixing terms in the action. We also comment on the extension
of our procedure to higher loop order and to general three-dimensional
Chern-Simons-matter models.Comment: 26 pages, 6 figures, JHEP3; v2: minor corrections and references
added; v3: introduction expanded, presentation of section 3.3.1 improved,
references added, version to appear in JHE
Using squeezed field to preserve two-atom entanglement against spontaneous emissions
Tunable interaction between two atoms in a cavity is realized by interacting
the two atoms with an extra controllable single-mode squeezed field. Such a
controllable interaction can be further used to control entanglement between
the two atoms against amplitude damping decoherence caused by spontaneous
emissions. For the independent amplitude damping decoherence channel,
entanglement will be lost completely without controls, while it can be
partially preserved by the proposed strategy. For the collective amplitude
damping decoherence channel, our strategy can enhance the entanglement compared
with the uncontrolled case when the entanglement of the uncontrolled stationary
state is not too large.Comment: 5 figure
Cross modal perception of body size in domestic dogs (Canis familiaris)
While the perception of size-related acoustic variation in animal vocalisations is well documented, little attention has been given to how this information might be integrated with corresponding visual information. Using a cross-modal design, we tested the ability of domestic dogs to match growls resynthesised to be typical of either a large or a small dog to size- matched models. Subjects looked at the size-matched model significantly more often and for a significantly longer duration than at the incorrect model, showing that they have the ability to relate information about body size from the acoustic domain to the appropriate visual category. Our study suggests that the perceptual and cognitive mechanisms at the basis of size assessment in mammals have a multisensory nature, and calls for further investigations of the multimodal processing of size information across animal species
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