1,323 research outputs found
Entanglement enhancement and postselection for two atoms interacting with thermal light
The evolution of entanglement for two identical two-level atoms coupled to a
resonant thermal field is studied for two different families of input states.
Entanglement enhancement is predicted for a well defined region of the
parameter space of one of these families. The most intriguing result is the
possibility of probabilistic production of maximally entangled atomic states
even if the input atomic state is factorized and the corresponding output state
is separable.Comment: accepted for publication in J. Phys.
Topology and Phases in Fermionic Systems
There can exist topological obstructions to continuously deforming a gapped
Hamiltonian for free fermions into a trivial form without closing the gap.
These topological obstructions are closely related to obstructions to the
existence of exponentially localized Wannier functions. We show that by taking
two copies of a gapped, free fermionic system with complex conjugate
Hamiltonians, it is always possible to overcome these obstructions. This allows
us to write the ground state in matrix product form using Grassman-valued bond
variables, and show insensitivity of the ground state density matrix to
boundary conditions.Comment: 4 pages, see also arxiv:0710.329
Prevalence of peripheral artery disease in diabetes mellitus: research article
Background: Peripheral artery disease is a major macrovascular complication of diabetes mellitus. Patients with diabetes mellitus have an increased prevalence of PAD. The ankle brachial pressure index is an easy, non invasive and often under utilised tool for diagnosis of PAD.Methods: In the present study, 100 patients from Western Uttar Pradesh with diabetes mellitus were enrolled to find out prevalence of peripheral vascular disease using ankle brachial pressure index and study the associated risk factors.Results: 59 percent of the subjects were female and 41 percent were male. Ankle-brachial index (ABI) examination of patients indicated Abnormal (ABI= <0.9), in 40 cases.Conclusions: it can be concluded that peripheral vascular disease in Diabetes Mellitus is more commonly associated than is generally believed
To study the association of high sensitivity C-reactive protein with metabolic syndrome
Background: Metabolic Syndrome is a constellation of dyslipidemia (elevated triglycerides, low high-density lipoproteins (HDL)), elevation of arterial blood pressure (BP), dysregulated glucose homeostasis, and increased abdominal obesity.Methods: We studied the association of high sensitivity C-reactive protein with metabolic syndrome by case-control method in our tertiary care hospital in West U.P.Results: The mean age of cases and controls was 52.6 ± 7.7 and 51.4±7.0 years, respectively. There were 25 (50%) male and 25 (50%) female in case groups, and 27 (54%) males and 23 (46%) females in control group. Our analysis revelaed that there was a significant association between hs-CRP and the central obesity when compared in case-control group (3.57 vs 0.96 mg/L) (p value <0.001). There was no significant association between hs-CRP and high triglycerides, hypertension, diabetes, and reduced high density lipoprotein cholesterol.Conclusions: Raised hsCRP level can be considered as a surrogate marker of chronic inflammation in patients with metabolic syndrome
Operator monotones, the reduction criterion and the relative entropy
We introduce the theory of operator monotone functions and employ it to
derive a new inequality relating the quantum relative entropy and the quantum
conditional entropy. We present applications of this new inequality and in
particular we prove a new lower bound on the relative entropy of entanglement
and other properties of entanglement measures.Comment: Final version accepted for publication, added references in reference
[1] and [13
On Late Time Tails in an Extreme Reissner-Nordstr\"om Black Hole: Frequency Domain Analysis
In this brief note, we revisit the study of the leading order late time decay
tails of massless scalar perturbations outside an extreme Reissner-Nordstr\"om
black hole. Previous authors have analysed this problem in the time domain; we
analyse the problem in the frequency domain. We first consider initial
perturbations with generic regular behaviour across the horizon on
characteristic surfaces. For this set-up, we reproduce some of the previous
results of Sela [arXiv:1510.06169] using Fourier methods. Next, we consider
related initial data on t=\mbox{const} hypersurfaces, and present decay
results at timelike infinity, near future null infinity, and near the future
horizon. Along the way, using the inversion symmetry of the
extreme Reissner-Nordstr\"om spacetime, we relate the higher multipole Aretakis
and Newman-Penrose constants for a massless scalar in this background.Comment: 22 pages; 2 figure
A network-aware framework for energy-efficient data acquisition in wireless sensor networks
Wireless sensor networks enable users to monitor the physical world at an extremely high fidelity. In order to collect the data generated by these tiny-scale devices, the data management community has proposed the utilization of declarative data-acquisition frameworks. While these frameworks have facilitated the energy-efficient retrieval of data from the physical environment, they were agnostic of the underlying network topology and also did not support advanced query processing semantics. In this paper we present KSpot+, a distributed network-aware framework that optimizes network efficiency by combining three components: (i) the tree balancing module, which balances the workload of each sensor node by constructing efficient network topologies; (ii) the workload balancing module, which minimizes data reception inefficiencies by synchronizing the sensor network activity intervals; and (iii) the query processing module, which supports advanced query processing semantics. In order to validate the efficiency of our approach, we have developed a prototype implementation of KSpot+ in nesC and JAVA. In our experimental evaluation, we thoroughly assess the performance of KSpot+ using real datasets and show that KSpot+ provides significant energy reductions under a variety of conditions, thus significantly prolonging the longevity of a WSN
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