Resonant Diffraction Radiation from an Ultrarelativistic Particle Moving Close to a Tilted Grating

A simple model for calculating the diffraction radiation characteristics from an ultrarelativistic charged particle moving close to a tilted ideally conducting strip is developed. Resonant diffraction radiation (RDR) is treated as a superposition of the radiation fields for periodically spaced strips. The RDR characteristics have been calculated as a function of the number of grating elements, tilted angle, and initial particle energy. An analogy with both the resonant transition radiation in absorbing medium and the parametric X-ray radiation is noted.Comment: 17 pages, 12 figures, RevTe

SomBe:Self-Organizing Map for Unstructured and Non-Coordinated iBeacon Constellations

Bluetooth Low Energy (BLE) devices such as iBeacons have been popularly deployed for Location Based Services (LBS), including indoor infrastructure monitoring, positioning, and navigation. In these applications, the positions of iBeacons are assumed to be known. However, the location information is often unavailable or inaccurate as most iBeacons were deployed by different external parties. In addition, manual localizing the already-deployed iBeacons is costly and even impractical, especially in large-scale and complex indoor environments. Therefore, we propose a novel method, namely SomeBe, which can localize deployed iBeacons with a minimal effort and invasiveness to existing infrastructures. Specifically, our approach uses cooperative multilateration based on Received Signal Strength (RSS) of available smartphones and WiFi access points (APs) in the environment. Both Bluetooth signal strengths (between smartphones and iBeacons) and WiFi signal strengths (between smartphones and APs) are jointly employed in a single optimization cost function to surpass the local minima. Requiring that the positions of the APs are known only, the proposed cost function can also localize the iBeacons without knowing the positions of smartphones. To improve the localization accuracy, we employ a clustering method based on the RSS values for the coarse estimation of iBeacons' positions. SomBe also can be used to simplify iBeacon deployment as it can localize the iBeacons with a minimal effort. The performance evaluation results of our testbed experiments as well as realistic simulations show that SomBe outperforms non-cooperative approaches with 85% better in terms of accuracy

Nuclear structure calculations with a separable approximation for Skyrme interactions

A finite rank separable approximation for the quasiparticle RPA calculations with Skyrme interactions that was proposed in our previous work is extended to take into account the coupling between one- and two-phonon terms in the wave functions of excited states. It is shown that characteristics calculated within the suggested approach are in a good agreement with available experimental data.Comment: 6 pages, proceedings of the International Symposium on Physics of Unstable Nuclei (ISPUN02), Halong Bay, Vietnam, November 20-25, 200

Effectiveness of three different walking prescription durations on total physical activity in normal- and overweight women.

OBJECTIVE: While there is a dose-response relationship between physical activity (PA) and health benefit, little is known about the effectiveness of different PA prescriptions on total daily PA. AIM: To test, under real-life conditions and using an objective, non-invasive measurement technique (accelerometry), the effect of prescribing additional physical activity (walking only) of different durations (30, 60 and 90 min/day) on compliance (to the activity prescribed) and compensation (to total daily PA). Participants in each group were prescribed 5 sessions of walking per week over 4 weeks. METHODS: 55 normal-weight and overweight women (mean BMI 25 ± 5 kg/m(2), height 165 ± 1 cm, weight 68 ± 2 kg and mean age 27 ± 1 years) were randomly assigned to 3 prescription groups: 30, 60 or 90 min/day PA. RESULTS: Walking duration resulted in an almost linear increase in the number of steps per day during the prescription period from an average of about 10,000 steps per day for the 30-min prescription to about 14,000 for the 90-min prescription. Compliance was excellent for the 30-min prescription but decreased significantly with 60-min and 90-min prescriptions. In parallel, degree of compensation subsequent to exercise increased progressively as length of prescription increased. CONCLUSION: A 30-min prescription of extra walking 5 times per week was well tolerated. However, in order to increase total PA further, much more than 60 min of walking may need to be prescribed in the majority of individuals. While total exercise 'volume' increased with prescriptions longer than 30 min, compliance to the prescription decreased and greater compensation was evident. © 2014 S. Karger GmbH, Freiburg

Environment Security for Traditional Craft Villages in Bac Ninh Province (Vietnam)

 Production and business activities in traditional craft villages leave a great impact on the security of their living environment. This study focuses on analysing environmental security of traditional craft villages in Bac Ninh province (Vietnam) to identify the environmental reality of this area, assess the environment impact on people and their attitudes on this issue. Data were collected from 350 households surveyed in 7 communes having wellknown traditional handicraft villages of Bac Ninh province, from local authorities and observation results of Bac Ninh People’s Committee from 2011 to 2016. Based on surveyed reaility, the author has made some recommendations to local authorities in ensuring environmental security for traditional craft villages in Bac Ninh (Vietnam) for the near future

Agronomy of a rice-based vegetable cultivation system in Vietnam. Constraints and recommendations for commercial market integration

A description of the vegetable cultivation system in two villages in the Red River Delta, Hanoi, Vietnam is provided. The production of dry land vegetables takes place in the cool winter season, while in the warm wet summer season, rice is cultivated. Major vegetable crops cultivated belong to the Brassicaceae, Solanaceae and Cucurbitaceae. Most of the crops are transplanted. Soil type varies from sandy loam to medium loam and soil organic matter content is low. Poor product quality, transplant production and soil conditions were identified as the major constraints for the production of high quality produce for upscale commercial markets. A proposal for a permanent vegetable production system is made

Thermodynamics of Random Ferromagnetic Antiferromagnetic Spin-1/2 Chains

Using the quantum Monte Carlo Loop algorithm, we calculate the temperature dependence of the uniform susceptibility, the specific heat, the correlation length, the generalized staggered susceptibility and magnetization of a spin-1/2 chain with random antiferromagnetic and ferromagnetic couplings, down to very low temperatures. Our data show a consistent scaling behavior in all the quantities and support strongly the conjecture drawn from the approximate real-space renormalization group treatment.A statistical analysis scheme is developed which will be useful for the search of scaling behavior in numerical and experimental data of random spin chains.Comment: 13 pages, 13 figures, RevTe

Structural characterization suggests models for monomeric and dimeric forms of full-length ezrin

Ezrin is a member of the ERM (ezrin–radixin–moesin) family of proteins that have been conserved through metazoan evolution. These proteins have dormant and active forms, where the latter links the actin cytoskeleton to membranes. ERM proteins have three domains: an N-terminal FERM [band Four-point-one (4.1) ERM] domain comprising three subdomains (F1, F2, and F3); a helical domain; and a C-terminal actin-binding domain. In the dormant form, FERM and C-terminal domains form a stable complex. We have determined crystal structures of the active FERM domain and the dormant FERM:C-terminal domain complex of human ezrin. We observe a bistable array of phenylalanine residues in the core of subdomain F3 that is mobile in the active form and locked in the dormant form. As subdomain F3 is pivotal in binding membrane proteins and phospholipids, these transitions may facilitate activation and signaling. Full-length ezrin forms stable monomers and dimers. We used small-angle X-ray scattering to determine the solution structures of these species. As expected, the monomer shows a globular domain with a protruding helical coiled coil. The dimer shows an elongated dumbbell structure that is twice as long as the monomer. By aligning ERM sequences spanning metazoan evolution, we show that the central helical region is conserved, preserving the heptad repeat. Using this, we have built a dimer model where each monomer forms half of an elongated antiparallel coiled coil with domain-swapped FERM:C-terminal domain complexes at each end. The model suggests that ERM dimers may bind to actin in a parallel fashion

Random Exchange Quantum Heisenberg Chains

The one-dimensional quantum Heisenberg model with random $\pm J$ bonds is studied for $S=\frac{1}{2}$ and $S=1$. The specific heat and the zero-field susceptibility are calculated by using high-temperature series expansions and quantum transfer matrix method. The susceptibility shows a Curie-like temperature dependence at low temperatures as well as at high temperatures. The numerical results for the specific heat suggest that there are anomalously many low-lying excitations. The qualitative nature of these excitations is discussed based on the exact diagonalization of finite size systems.Comment: 13 pages, RevTex, 12 figures available on request ([email protected]