31 research outputs found
An Essential Physiological Role for MCT8 in Bone in Male Mice
T3 is an important regulator of skeletal development and adult bone maintenance. Thyroid hormone
action requires efficient transport of T4 and T3 into target cells. We hypothesized that
monocarboxylate transporter (MCT) 8, encoded by Mct8 on the X-chromosome, is an essential
thyroid hormone transporter in bone. To test this hypothesis, we determined the juvenile and adult
skeletal phenotypes of male Mct8 knockout mice (Mct8KO) and Mct8D1D2KO compound mutants,
which additionally lack the ability to convert the prohormone T4 to the active hormone T3. Prenatal
skeletal development was normal in both Mct8KO and Mct8D1D2KO mice, whereas postnatal
endochondral ossification and linear growth were delayed in both Mct8KO and Mct8D1D2KO mice.
Furthermore, bone mass and mineralization were decreased in adult Mct8KO and Mct8D1D2KO
mice, and compound mutants also had reduced bone strength. Delayed bone development and
maturation in Mct8KO and Mct8D1D2KO mice is consistent with decreased thyroid hormone action
in growth plate chondrocytes despite elevated serum T3 concentrations, whereas low bone mass
and osteoporosis reflects increased thyroid hormone action in adult bone due to elevated systemic
T3 levels. These studies identify an essential physiological requirement for MCT8 in chondrocytes,
and demonstrate a role for additional transporters in other skeletal cells during adult bone
maintenance
Magnetotransport in two-dimensional electron gas at large filling factors
We derive the quantum Boltzmann equation for the two-dimensional electron gas
in a magnetic field such that the filling factor . This equation
describes all of the effects of the external fields on the impurity collision
integral including Shubnikov-de Haas oscillations, smooth part of the
magnetoresistance, and non-linear transport. Furthemore, we obtain quantitative
results for the effect of the external microwave radiation on the linear and
non-linear transport in the system. Our findings are relevant for the
description of the oscillating resistivity discovered by Zudov {\em et al.},
zero-resistance state discovered by Mani {\em et al.} and Zudov {\em et al.},
and for the microscopic justification of the model of Andreev {\em et al.}. We
also present semiclassical picture for the qualitative consideration of the
effects of the applied field on the collision integral.Comment: 28 pages, 19 figures; The discussion of the role of the effect of the
microwave field on the distribution function is revised (see also
cond-mat/0310668). Accepted in Phys. Rev.
The antiferromagnetic phi4 Model, I. The Mean-field Solution
Certain higher dimensional operators of the lagrangian may render the vacuum
inhomogeneous. A rather rich phase structure of the phi4 scalar model in four
dimensions is presented by means of the mean-field approximation. One finds
para- ferro- ferri- and antiferromagnetic phases and
commensurate-incommensurate transitions. There are several particles described
by the same quantum field in a manner similar to the species doubling of the
lattice fermions. It is pointed out that chiral bosons can be introduced in the
lattice regularized theory.Comment: To appear in Phys. Rev.
Human Resource Flexibility as a Mediating Variable Between High Performance Work Systems and Performance
Much of the human resource management literature has demonstrated the impact of high performance
work systems (HPWS) on organizational performance. A new generation of studies is
emerging in this literature that recommends the inclusion of mediating variables between HPWS
and organizational performance. The increasing rate of dynamism in competitive environments
suggests that measures of employee adaptability should be included as a mechanism that may
explain the relevance of HPWS to firm competitiveness. On a sample of 226 Spanish firms, the
study’s results confirm that HPWS influences performance through its impact on the firm’s
human resource (HR) flexibility
Cross-cultural validity of the self-stigma of seeking help (SSOSH) scale: Examination across six nations
Researchers have found that the stigma associated with seeking therapyparticularly self-stigma can inhibit the use of psychological services. Yet, most of the research on self-stigma has been conducted in the United States. This is a considerable limitation, as the role of self-stigma in the help-seeking process may vary across cultural groups. However, to examine cross-cultural variations, researchers must first develop culturally valid scales. Therefore, this study examined scale validity and reliability of the widely used Self-Stigma of Seeking Help scale (SSOSH; Vogel, Wade, & Haake, 2006) across samples from 6 different countries (England, Greece, Israel, Taiwan, Turkey, and the United States). Specifically, we used a confirmatory factor analysis framework to conduct measurement invariance analysis and latent mean comparisons of the SSOSH across the 6 sampled countries. Overall, the results suggested that the SSOSH has a similar univariate structure across countries and is sufficiently invariant across countries to be used to explore cultural differences in the way that self-stigma relates to help-seeking behavior. © 2012 American Psychological Association
Stigma of Seeking Psychological Services: Examining College Students Across Ten Countries/Regions
A Non-adaptive Stochastic Local Search Algorithm for the CHeSC 2011 Competition
In this work, we present our submission for the Cross-domain Heuristic Search Challenge 2011. We implemented a stochastic local search algorithm that consists of several algorithm schemata that have been offline-tuned on four sample problem domains. The schemata are based on all families of low-level heuristics available in the framework used in the competition with the exception of crossover heuristics. Our algorithm goes through an initial phase that filters dominated low-level heuristics, followed by an algorithm schemata selection implemented in a race. The winning schema is run for the remaining computation time. Our algorithm ranked seventh in the competition results. In this paper, we present the results obtained after a more careful tuning, and a different combination of algorithm schemata included in the final algorithm design. This improved version would rank fourth in the competition. © 2012 Springer-Verlag.SCOPUS: cp.kinfo:eu-repo/semantics/publishe
Eficiência agronômica de nova formulação de inoculante rizobiano para feijão-caupi
O objetivo deste trabalho foi avaliar a eficiência agronômica da formulação polimérica IPC 2.2 como veículo de inoculação para feijão-caupi. Foi avaliada a sobrevivência de células aos 180 dias de armazenamento. Em experimento de campo, comparou-se a formulação polimérica com a turfosa e a líquida e com adubação nitrogenada de 50 e 80 kg ha-¹ de N e um controle absoluto. A formulação IPC 2.2 manteve concentração de células superior a 109 g-1 após 180 dias e, em campo, proporcionou produtividade de grãos superior à do controle absoluto e igual à dos tratamentos nitrogenados e veículos turfoso e líquido