Large magneto-thermal effect and the spin-phonon coupling in a parent insulating cuprate Pr_{1.3}La_{0.7}CuO_4

The magnetic-field (H) dependence of the thermal conductivity \kappa of Pr_{1.3}La_{0.7}CuO_4 is found to show a pronounced minimum for in-plane fields at low temperature, which is best attributed to the scattering of phonons by free spins that are seen by a Schottky-type specific heat and a Curie-Weiss susceptibility. Besides pointing to a strong spin-phonon coupling in cuprates, the present result demonstrates that the H-dependence of the phonon heat transport should not be naively neglected when discussing the \kappa(H) behavior of cuprates, since the Schottky anomaly is ubiquitously found in cuprates at any doping.Comment: 6 pages, 4 figures, accepted for publication in Phys. Rev.

Dilute Bose gas in two dimensions: Density expansions and the Gross-Pitaevskii equation

A dilute two-dimensional (2D) Bose gas at zero temperature is studied by the method developed earlier by the authors. Low density expansions are derived for the chemical potential, ground state energy, kinetic and interaction energies. The expansion parameter is found to be a dimensionless in-medium scattering amplitude u obeying the equation 1/u+\ln u=-\ln(na^2\pi)-2\gamma, where na^2 and \gamma are the gas parameter and the Euler constant, respectively. It is shown that the ground state energy is mostly kinetic in the low density limit; this result does not depend on a specific form of the pairwise interaction potential, contrary to 3D case. A new form of 2D Gross-Pitaevskii equation is proposed within our scheme.Comment: 4 pages, REVTeX, no figure

OpenADAM: an open source genome-wide association data management system for Affymetrix SNP arrays

BACKGROUND: Large scale genome-wide association studies have become popular since the introduction of high throughput genotyping platforms. Efficient management of the vast array of data generated poses many challenges. DESCRIPTION: We have developed an open source web-based data management system for the large amount of genotype data generated from the Affymetrix GeneChip Mapping Array and Affymetrix Genome-Wide Human SNP Array platforms. The database supports genotype calling using DM, BRLMM, BRLMM-P or Birdseed algorithms provided by the Affymetrix Power Tools. The genotype and corresponding pedigree data are stored in a relational database for efficient downstream data manipulation and analysis, such as calculation of allele and genotype frequencies, sample identity checking, and export of genotype data in various file formats for analysis using commonly-available software. A novel method for genotyping error estimation is implemented using linkage disequilibrium information from the HapMap project. All functionalities are accessible via a web-based user interface. CONCLUSION: OpenADAM provides an open source database system for management of Affymetrix genome-wide association SNP data.published_or_final_versio

Does Dysbiosis Play a Role in Age-Related Hearing Impairment?

Age-related hearing impairment (ARHI) is prevalent in older adults, affecting at least 60% of people by the time they reach 71 to 80 years of age.1 The number of people with ARHI will necessarily increase as humans live longer and a greater proportion of the population is older.2 Hearing loss does not just impact communication; it is associated with loneliness and depression, cognitive decline and dementia, as well as reduced physical well-being.3-6 A decade ago, an international report calculated that hearing loss cost Europe £213 billion annually.7 There is currently no effective drug treatment for hearing loss. Hearing aids (average cost £2,300/pair) are the most commonly prescribed ameliorative therapy, but uptake is low; and among those who obtain hearing aids, a high proportion do not use them or are dissatisfied with them. Hearing loss prevention is therefore of compelling necessity, and genetic studies will help us understand how and why people lose their hearing ability and will inform prevention strategies

Theory of superfluidity and drag force in the one-dimensional Bose gas

The one-dimensional Bose gas is an unusual superfluid. In contrast to higher spatial dimensions, the existence of non-classical rotational inertia is not directly linked to the dissipationless motion of infinitesimal impurities. Recently, experimental tests with ultracold atoms have begun and quantitative predictions for the drag force experienced by moving obstacles have become available. This topical review discusses the drag force obtained from linear response theory in relation to Landau's criterion of superfluidity. Based upon improved analytical and numerical understanding of the dynamical structure factor, results for different obstacle potentials are obtained, including single impurities, optical lattices and random potentials generated from speckle patterns. The dynamical breakdown of superfluidity in random potentials is discussed in relation to Anderson localization and the predicted superfluid-insulator transition in these systems.Comment: 17 pages, 12 figures, mini-review prepared for the special issue of Frontiers of Physics "Recent Progresses on Quantum Dynamics of Ultracold Atoms and Future Quantum Technologies", edited by Profs. Lee, Ueda, and Drummon

Bound pair states beyond the condensate for Fermi systems below T_c: the pseudogap as a necessary condition

As is known, the 1/q^2 theorem of Bogoliubov asserts that the mean density of the fermion pair states with the total momentum q obeys the inequality n_q > C/q^2 (q \to 0) in the case of the Fermi system taken at nonzero temperature and in the superconducting state provided the interaction term of its Hamiltonian is locally gauge invariant. With the principle of correlation weakening it is proved in this paper that the reason for the mentioned singular behaviour of n_q is the presence of the bound states of particle pairs with nonzero total momenta. Thus, below the temperature of the superconducting phase transition there always exist the bound states of the fermion couples beyond the pair condensate. If the pseudogap observed in the normal phase of the high-T_c superconductors is stipulated by the presence of the electron bound pairs, then the derived result suggests, in a model-independent manner, that the pseudogap survives below T_c.Comment: REVTeX, 8 pages, no figures, submitted to Phys. Rev.

Model for determining the competitive identity of cities in a digital economy

The term competitive identity of cities was introduced by Enholt [1] when considering the notion of territory marketing. Such an indicator is significant for determining the investment attractiveness of the territorial entity, and as a consequence of the opportunities for the development of the Territory and its directions. The assessment and prospects for the development of territories are determined by a set of indicators that are quite stable in time, then it is necessary to determine how to predict the directions for improving the efficiency of investment policy, including in the transition to the digital economy. © 2020 American Institute of Physics Inc.. All rights reserved

VREDEN RUSSIAN RESEARCH INSTITUTE OF TRAUMATOLOGY AND ORTHOPEDICS

Currently, the use of bone allografts for reconstructive orthopedic surgery in clinical practice around the world is becoming a common procedure. Bone allografts are the first substitute material to the autologous bone and the best alternative to any artificial substituting material. The methods used for the preservation, processing and sterilization of bone are changing and evolving with time. The main goals remain the same including exclusion of infections and creation of the material with sustained properties of the normal bone.The present review reflects the essential methods for biological tissue processing, sterilization and preservation with the analysis of the key requirements for manufacturing of safe allogeneic osteoplastic materials with osteoinductive, osteoconductive and osteogenic properties