Inclusive probability to record an electron in elastic electromagnetic scattering by a spin one-half hadron wave packet

The inclusive probability to record an electron in elastic electromagnetic scattering of an electron by a spin one-half hadron is obtained, the initial quantum states of the electron and the hadron being described by the density matrices of a general form. Contrary to the Rosenbluth formula for the differential cross-section for this process, the first nontrivial contribution to the inclusive probability turns out to be of order $\alpha$ and not $\alpha^2$. This contribution describes the interference between the trivial contribution to the $S$-matrix and the leading contribution to its connected part. The explicit expression for this interference terms is derived. It is shown that the same interference term arises when the electron is scattered by the classical electromagnetic field produced by the hadron electromagnetic current averaged with respect to the free evolving density matrix of the hadron, even in the case of a single hadron. The interference term describes coherent scattering of the electron by the hadron wave packet and is immune to the quantum recoil experienced by a hadron due to scattering. The effective electron mass operator is found on the mass-shell.Comment: 14 pp., 2 fig

THE RESEARCH OF THE STRUCTURE OF PLATES OF COPPER AND MOLYBDENUM ARE CONNECTED BY EXPLOSION WELDING

В работе представлены результаты исследования структуры и микротвердости соединения пластин меди и молибдена, полученные методом сварки взрывом. Показано, что граница между свариваемыми материалами имеет волнообразный характер. В отдельных участках границы образуются зоны перемешивания двух материалов. Методом просвечивающей электронной микроскопии установлено, что зоны перемешивания склонны к формированию структуры механической смеси.The article presents the results of the research of the structure and microhardness of the molybdenum and copper plates combination produced by explosion welding. It is shown that the boundary between the welded materials has an undulatory character. The mixing zones are formed in some parts of the boundary of the two materials. The mixing zones have mechanical mix structure. This structure was determined by means of transmission electron microscopy

Prevalence and Correlates of Self-Rated Successful Aging Among Older Women Living With HIV

BACKGROUND: Despite marked gains in longevity attributable to antiretroviral therapy (ART), older women living with HIV (OWLH) experience substantial health challenges, and few studies addressed whether they can achieve successful aging (SA). This is among the first studies examining prevalence and psychosocial correlates of self-rated SA (SRSA) among OWLH and women at risk of HIV. METHODS: The sample included 386 OWLH and 137 HIV-seronegative women enrolled in the Women's Interagency HIV Study (WIHS) who were aged 50 years and older and participated in the "From Surviving to Thriving" (FROST) substudy. The FROST survey included measures of SRSA and positive psychosocial constructs. RESULTS: Participants were on average 57 years (SD = 5.3), 74% African American and 30% unemployed. Among OWLH, 94% were on ART and 73% were virally suppressed. Compared with OWLH, a higher proportion of HIV-seronegative women had an annual income ≤ $6000, no health insurance, and reported lower optimism and health-related quality of life. We found no differences in SRSA prevalence by HIV status: 84% of OWLH and 83% of HIV-seronegative women reported SRSA ≥7 (range = 2-10, higher scores signify better SRSA). Having SRSA ≥7 was associated with higher levels of positive psychosocial characteristics (eg, resilience and optimism) among both OWLH and HIV-seronegative women. CONCLUSIONS: SRSA is achievable among older women with and at risk of HIV despite health complications. Among disadvantaged women, factors other than HIV may be primary drivers of SRSA. Future research is needed to examine determinants of SRSA and to design public health interventions enhancing SA within this population

Steady state of atoms in a resonant field with elliptical polarization

We present a complete set of analytical and invariant expressions for the steady-state density matrix of atoms in a resonant radiation field with arbitrary intensity and polarization. The field drives the closed dipole transition with arbitrary values of the angular momenta $J_{g}$ and $J_{e}$ of the ground and excited state. The steady-state density matrix is expressed in terms of spherical harmonics of a complex direction given by the field polarization vector. The generalization to the case of broad-band radiation is given. We indicate various applications of these results.Comment: revtex, 26 pages, including 3 eps figures; PRA accepted for publication;v2 three typos are fixe

Влияние количества биоптатов, взятых при таргетной биопсии предстательной железы, на вероятность положительного результата у пациентов с клинически значимым раком предстательной железы

Background. Targeted biopsy is proposed as a method of choice in the algorithm of prostate cancer diagnosis, but not all the features of method has been evaluated. Objective: determine the rational number of targeted biopsy samples in patients with clinically significant prostate cancer. Materials and methods. The magnetic resonance imaging and fusion biopsy data of 156 patients with suspected prostate cancer were retrospectively evaluated. Results and conclusion. In the study statistically significant dependence of the positive histological results in patients with clinically significant prostate cancer from the number of biopsy samples was found. The potential probability of a false negative histological examination with an insufficient number of biopsy samples was noted. These results confirm the latest published data of potential targeted biopsy false in true positive patients after multiparametric magnetic resonance imaging. An increase in the number of biopsy samples in the target lesion reduces the likelihood of false-negative results. The main causes of such discrepancy are some technical laxity and the heterogeneous histological structure of prostate cancer. Increase the number of biopsy cores can reduce the likelihood of false-negative results. © 2020 ABC-press Publishing House. All rights reserved

Psychosocial Mechanisms of Self-rated Successful Aging with HIV: A Structural Equation Model

This study tested a conceptual psychosocial model of self-rated successful aging (SRSA) with HIV. Our sample (n = 356) included older women living with HIV (OWLH): average age 56.5 years, 73% Black. SRSA was assessed using a research-based 10-point scale (higher scores = better outcomes). We conducted adjusted structural equation modeling. The global model included two latent variables—protective attributes (composite of positive psychosocial factors: resilience, personal mastery, optimism, spirituality) and psychological distress (composite of negative psychosocial factors: anxiety, depression, loneliness, internalized HIV-related stigma). The model showed good fit (χ2(58) = 76, p = 0.06; RMSEA = 0.03; CFI = 0.99). Increased protective attributes were associated with improved SRSA both directly and mediated by improved coping with stress. While psychological distress did not have a direct effect on SRSA, it was indirectly associated with worsened SRSA via diminished protective attributes and via decreased coping with stress. Findings suggest the need for interventions enhancing positive and mitigating negative psychosocial factors in OWLH

Ectothiorhodospira variabilis, sp. nov., an alkaliphilic and halophilic purple sulfur bacterium from soda lakes

During studies of moderately halophilic strains of Ectothiorhodospira from steppe soda lakes, we found a novel group of bacteria related to Ectothiorhodospira haloalkaliphila with salt optima at 50–80 g NaCl l”1. Phylogenetic analysis using 16S rRNA gene sequences of strains from soda lakes in Mongolia, Egypt and Siberia revealed separation of the group of new isolates from other Ectothiorhodospira species, including the closely related Ect. haloalkaliphila. DNA–DNA hybridization studies demonstrated that the new isolates form a homogeneous group at the species level, but at the same time are distinct from related species such as Ect. haloalkaliphila, Ect. vacuolata, Ect. shaposhnikovii and Ect. marina. The new isolates are considered to be strains of a novel species, for which the name Ectothiorhodospira variabilis sp. nov. is proposed, with the type strain WN22T (5VKM B-2479T 5DSM 21381T). Photosynthetic pigments of the novel species are bacteriochlorophyll a and carotenoids of the spirilloxanthin series with spirilloxanthin and derivatives thereof, together with small amounts of lycopene and rhodopin. Gas vesicles are formed by most of the strains, particularly in media containing yeast extract (0.5 g l”1) and acetate (0.5–2.0 g l”1). Sequence analysis of nifH (nitrogenase) and cbbL (RuBisCO) confirmed the assignment of the strains to the genus Ectothiorhodospira and in particular the close relationship to Ect. haloalkaliphila. The novel species Ect. variabilis is found in soda lakes separated by great geographical distances and is an alkaliphilic and halophilic bacterium that tolerates salt concentrations up to 150–200 g NaCl l”1

Breakup reaction models for two- and three-cluster projectiles

Breakup reactions are one of the main tools for the study of exotic nuclei, and in particular of their continuum. In order to get valuable information from measurements, a precise reaction model coupled to a fair description of the projectile is needed. We assume that the projectile initially possesses a cluster structure, which is revealed by the dissociation process. This structure is described by a few-body Hamiltonian involving effective forces between the clusters. Within this assumption, we review various reaction models. In semiclassical models, the projectile-target relative motion is described by a classical trajectory and the reaction properties are deduced by solving a time-dependent Schroedinger equation. We then describe the principle and variants of the eikonal approximation: the dynamical eikonal approximation, the standard eikonal approximation, and a corrected version avoiding Coulomb divergence. Finally, we present the continuum-discretized coupled-channel method (CDCC), in which the Schroedinger equation is solved with the projectile continuum approximated by square-integrable states. These models are first illustrated by applications to two-cluster projectiles for studies of nuclei far from stability and of reactions useful in astrophysics. Recent extensions to three-cluster projectiles, like two-neutron halo nuclei, are then presented and discussed. We end this review with some views of the future in breakup-reaction theory.Comment: Will constitute a chapter of "Clusters in Nuclei - Vol.2." to be published as a volume of "Lecture Notes in Physics" (Springer

Роль Е-кадхерина в неопластической эволюции эпителиальных клеток

Interaction of the extracellular domains of the transmembrane proteins cadherins provides cell-cell adhesion. For many years epithelial E- cadherin was regarded as a tumor suppressor and was used as a prognostic marker in cancer. Suppression of E-cadherin expression was observed in many carcinomas. During recent years, the tumor suppressor function of E-cadherin is being reconsidered. It has been shown that ductal breast carcinomas, colorectal carcinomas, oral cavity carcinomas, and squamous cell carcinomas of the head and neck can retain E-cadherin expression. Immunohistochemical staining with a panel of monoclonal antibodies revealed membrane localization of E-cadherin in many tumors. It was shown that transformed epithelial cells in vitro form dynamic adherens junctions that are essential for the effective collective migration of these cells.Трансмембранные белки кадхерины обеспечивают межклеточную адгезию через взаимодействие внеклеточных доменов. На протяжении многих лет эпителиальный Е-кадхерин считался опухолевым супрессором и рассматривался в качестве прогностического маркера у онкологических больных. Угнетение экспрессии Е-кадхерина наблюдали во многих карциномах. В последние несколько лет пересматриваются представления о супрессирующей оли Е-кадхерина. Показано, что протоковые карциномы молочной железы, карциномы толстой кишки, карциномы полости рта, плоскоклеточные карциномы головы и шеи могут сохранять экспрессию Е-кадхерина. При иммуногистохимическом окрашивании с использованием панели моноклональных антител во многих опухолях была выявлена мембранная локализация Е-кадхерина. В трансформированных эпителиоцитах in vitro были обнаружены динамичные межклеточные адгезионные контакты, образованные Е-кадхерином, которые важны для эффективной коллективной миграции клеток