Thermal correction to the Casimir force, radiative heat transfer, and an experiment

The low-temperature asymptotic expressions for the Casimir interaction between two real metals described by Leontovich surface impedance are obtained in the framework of thermal quantum field theory. It is shown that the Casimir entropy computed using the impedance of infrared optics vanishes in the limit of zero temperature. By contrast, the Casimir entropy computed using the impedance of the Drude model attains at zero temperature a positive value which depends on the parameters of a system, i.e., the Nernst heat theorem is violated. Thus, the impedance of infrared optics withstands the thermodynamic test, whereas the impedance of the Drude model does not. We also perform a phenomenological analysis of the thermal Casimir force and of the radiative heat transfer through a vacuum gap between real metal plates. The characterization of a metal by means of the Leontovich impedance of the Drude model is shown to be inconsistent with experiment at separations of a few hundred nanometers. A modification of the impedance of infrared optics is suggested taking into account relaxation processes. The power of radiative heat transfer predicted from this impedance is several times less than previous predictions due to different contributions from the transverse electric evanescent waves. The physical meaning of low frequencies in the Lifshitz formula is discussed. It is concluded that new measurements of radiative heat transfer are required to find out the adequate description of a metal in the theory of electromagnetic fluctuations.Comment: 19 pages, 4 figures. svjour.cls is used, to appear in Eur. Phys. J.

Gender differentials in the impact of parental death: Adolescent's sexual behaviour and risk of HIV infection in rural South Africa

Using data from a longitudinal surveillance study from rural South Africa, we investigated the odds of sexual debut, pregnancy and HIV infection of 15- to 19-year-old adolescents by parental survival. Using descriptive statistics and logistic regressions, we examine the relative risk of orphans compared with non-orphans to have ever had sex, being pregnant and being HIV infected, adjusting for age, sex, socio-economic status, education, being employed and residency. Of 8274 adolescents, 42% were orphaned (one or both parents died). Over 80% of adolescents remained in school, but orphans were significantly more likely to lag behind in grade for age. Female adolescent maternal (aOR 1.32, 95% CI 1.071.62), paternal (aOR 1.26, 95% CI 1.061.49) and dual (aOR 1.37, 95% CI 1.051.78) orphans were significantly more likely than non-orphaned females to have ever had sex; among males it was only paternal (aOR 1.27, 95% CI 1.051.53) orphans. Maternal (aOR 1.49, 95% CI 1.032.15) and dual (aOR 1.74, 95% CI 1.112.73) female orphans relative to non-orphaned females were significantly more likely to be HIV infected; male paternal (aOR 3.41, 95% CI 1.378.46) and dual (aOR 3.54, 95% CI 1.0611.86) orphans had over three-fold the odds of being infected. There was strong evidence that death of mother for girls was associated with increased vulnerability to earlier sexual debut and HIV infection, while fathers appeared to play a significant role in both their son's and daughter's lives

Scale issues in soil moisture modelling: problems and prospects

Soil moisture storage is an important component of the hydrological cycle and plays a key role in land-surface-atmosphere interaction. The soil-moisture storage equation in this study considers precipitation as an input and soil moisture as a residual term for runoff and evapotranspiration. A number of models have been developed to estimate soil moisture storage and the components of the soil-moisture storage equation. A detailed discussion of the impli cation of the scale of application of these models reports that it is not possible to extrapolate processes and their estimates from the small to the large scale. It is also noted that physically based models for small-scale applications are sufficiently detailed to reproduce land-surface- atmosphere interactions. On the other hand, models for large-scale applications oversimplify the processes. Recently developed physically based models for large-scale applications can only be applied to limited uses because of data restrictions and the problems associated with land surface characterization. It is reported that remote sensing can play an important role in over coming the problems related to the unavailability of data and the land surface characterization of large-scale applications of these physically based models when estimating soil moisture storage.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Special Libraries, April 1933

Volume 24, Issue 3https://scholarworks.sjsu.edu/sla_sl_1933/1002/thumbnail.jp

Soccer and homosexuality: the conflicts that lie within the affective game of the coach-adolescent athlete relationship

Discussions regarding homosexuality within a sports context are mediated by emotional nuances, especially in the world of soccer, where practitioners are required to have attributes such as strength, masculinity and aggressiveness. As a consequence, this work aimed to analyze the symbolic representation of homosexual relationships between adolescent soccer players and their coaches; and, furthermore, to understand the intention behind homoerotic relationships that are established between members of the management team and its players. In this study, researchers used the life history methodology, with participation from three adolescent athletes, ages 14, 15 and 16, and three former athletes, ages 26, 28 and 45, who we called speakers. Based on the collection and analysis of research participants’ testimonies, homosexual relations were found to have occurred between athletes and coaches, or between athletes and other members of the management team, as a part of a “social contract” that is exclusively linked to their professional objectives. These relationships appear to be purely objective; authentic affective links are absent, due apparently to the transient nature of the athletes in these groups. Too, this context is usually marked by the athlete’s physical and emotional vulnerability, and the agreements he makes within this context are accompanied with moral dilemmas, because such adolescents idealize the coach as a paternal archetype.“Futebol e homossexualidade: Os conflitos que se encontram dentro do jogo afetivo da relação treinador-atleta adolescente.” As discussões a respeito da homossexualidade no contexto esportivo são mediadas por nuanças emocionais, especialmente no mundo do futebol que exige de seus praticantes atributos de força, virilidade e agressividade. Por este motivo este trabalho teve como objetivos diagnosticar existência de relações homossexuais entre atletas adolescentes da modalidade de futebol e seus técnicos e sua representação simbólica e ainda, compreender a intencionalidade das relações homoafetivas que se estabelecem entre componentes da equipe diretiva e os jogadores. Esta pesquisa é de natureza qualitativa e a técnica adotada foi a “história de vida” e a participação de três atletas adolescentes em atividade, com idade de 14, 15 e 16 anos e três ex-atletas profissionais, com idades 26, 28 e 45 anos serviram de base metodológica. A partir da análise e tratamento dos depoimentos verificou-se que ocorreram relações homossexuais nas categorias de base envolvendo técnico e atleta, ou com outros membros da equipe diretiva, como parte dos contratos sociais, ligados exclusivamente a objetivos profissionais. Estas relações parecem ser puramente objetais, não parecendo existir vínculos afetivos duradouros, aparentemente, devido à natureza transitória de atletas nesses grupos. Também, nesses ambientes, muitas vezes marcados pela vulnerabilidade física e emocional dos atletas, os acertos para as relações homossexuais são permeadas por dilemas morais, tendo em vista que os atletas adolescentes idealizam o treinador como o arquétipo paterno ideal.“El fútbol y la homosexualidad: Los conflictos que se encuentran dentro del juego afectivo de la relación atleta-entrenador de los adolescentes.” Las discusiones sobre la homosexualidad en contexto deportivo están mediadas por matices emocionales, sobre todo en el mundo del fútbol que exige a sus jugadores atributos como la fuerza, la virilidad y los jugadores. En este estudio, los investigadores utilizaron la metodología de la historia de vida, con la participación de tres atletas adolescentes, con 14, 15 y 16 años, y tres ex atletas con 26, 28 y 45 años, que llamamos ‘oradores’. Basado en la recogida y análisis de testimonios de participantes en la investigación, se encontró que las relaciones homosexuales que se han producido entre los atletas y entrenadores, o entre atletas y otros miembros del equipo de gestión, son como parte de un “contrato social” que está vinculado exclusivamente a sus objetivos profesionales. Estas relaciones parecen ser solamente como un objeto; porque a veces no hay vínculos afectivos auténticos, debido aparentemente a la naturaleza transitoria de los atletas en estos grupos. Demasiado, este contexto es generalmente marcado por la vulnerabilidad física y emocional del deportista, y los acuerdos que hace dentro de este contexto se acompañan con dilemas morales, debido a que tales adolescentes idealizan el entrenador como un arquetipo paterno. la agresividad. Por lo tanto, este estudio tuvo como objetivo diagnosticar la existencia de relaciones homosexuales entre adolescentes atletas de fútbol y sus entrenadores y la representación simbólica de estas relaciones. También comprender la intencionalidad de las relaciones homoafetivas que se intercambian entre algunos componentes del equipo directivo y(undefined

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362