47 research outputs found

    Bott periodicity and stable quantum classes

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    We use Bott periodicity to relate previously defined quantum classes to certain "exotic Chern classes" on BUBU. This provides an interesting computational and theoretical framework for some Gromov-Witten invariants connected with cohomological field theories. This framework has applications to study of higher dimensional, Hamiltonian rigidity aspects of Hofer geometry of CPn \mathbb{CP} ^{n}, one of which we discuss here.Comment: prepublication versio

    Dynamic correlations of the Coulomb Luttinger liquid

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    The dynamic density response function, form-factor, and spectral function of a Luttinger liquid with Coulomb electron-electron interaction are studied with the emphasis on the short-range electron correlations. The Coulomb interaction changes dramatically the density response function as compared to the case of the short-ranged interaction. The form of the density response function is smoothing with time, and the oscillatory structure appears. However, the spectral functions remain qualitatively the same. The dynamic form-factor contains the δ\delta-peak in the long-wave region, corresponding to one-boson excitations. Besides, the multi-boson-excitations band exists in the wave-number region near to 2kF2k_F. The dynamic form-factor diverges at the edges of this band, while the dielectric function goes to zero there, which indicates the appearance of a soft mode. We develop a method to analyze the asymptotics of the spectral functions near to the edges of the multi-boson-excitations band.Comment: 11 pages, 3 figures, submitted to PR

    Thermodynamic properties of asymptotically anti-de Sitter black holes in d=4 Einstein-Yang-Mills theory

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    We investigate the thermodynamics of spherically symmetric black hole solutions in a four-dimensional Einstein-Yang-Mills-SU(2) theory with a negative cosmological constant. Special attention is paid to configurations with a unit magnetic charge. We find that a set of Reissner-Nordstrom-Anti-de Sitter black holes can become unstable to forming non-Abelian hair. However, the hairy black holes are never thermodynamically favoured over the full set of abelian monopole solutions. The thermodynamics of the generic configurations possessing a noninteger magnetic charge is also discussed. (C) 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license

    Mining Prognostic Significance of MEG3 in Human Breast Cancer Using Bioinformatics Analysis

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    Background/Aims: Maternally expressed gene 3 (MEG3) is an imprinted gene with maternal expression, which may function as a tumor suppressor by inhibiting angiogenesis. To identify the prognostic value of MEG3 in breast cancer, systematic analysis was performed in this study. Methods: To evaluate gene alteration during breast carcinogenesis, we explored MEG3 expression using the Serial Analysis of Gene Expression Genie suite and Oncomine analysis. The prognostic roles of MEG3 in breast cancer were investigated using the PrognoScan database. The heat map and methylation status of MEG3 were determined using the UCSC Genome Browser. Results: We found that MEG3 was more frequently downregulated in breast cancer than in normal tissues and this correlated with prognosis. However, estrogen receptor and progesterone receptor status were found to be positively correlated with MEG3 expression. Conversely, basal-like status, triple-negative breast cancer status, and Scarff Bloom & Richardson grade criterion were negatively correlated with MEG3 expression. Following data mining in multiple big data databases, we confirmed a positive correlation between MEG3 and heparan sulfate proteoglycan 2 (HSPG2) expression in breast cancer tissues. Conclusion: MEG3 could be adopted as a marker to predict the prognosis of breast cancer with HSPG2. However, large-scale and comprehensive research is needed to clarify our results

    Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

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    In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

    The Cooling Effect of an Urban River and Its Interaction with the Littoral Built Environment in Mitigating Heat Stress: A Mobile Measurement Study

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    Rivers within urban areas could influence the thermal environment by modifying air temperature (AT) and relative humidity (RH). To further explore the cooling effect of a large river on surrounding urban areas, we conducted mobile measurements near the Yangtze River in Wuhan during a hot and humid summer day. This research examined the river cooling effect, determined the thresholds of the cooling and humidifying distance using a third-order polynomial method, assessed littoral heat stress at the pedestrian level and investigated the impact of the littoral built environment using stepwise regression analysis. The results revealed that (1) the cooling and humidifying effect of the river was up to 3.55 °C, 1741 m and 17.25%, 1369 m in the daytime, which was much greater than that at night; (2) the river significantly mitigated pedestrian heat stress within 1200 m from the riverbank in the daytime, but showed a weak negative effect at night; (3) the built environment has a significant impact on the littoral areas, e.g., urban greening during the daytime and building morphology at night. The findings of this study provide empirical evidence for the cooling effect of a large river in urban areas and further support climate-sensitive planning and design for our thermal environment

    The Cooling Effect of an Urban River and Its Interaction with the Littoral Built Environment in Mitigating Heat Stress: A Mobile Measurement Study

    No full text
    Rivers within urban areas could influence the thermal environment by modifying air temperature (AT) and relative humidity (RH). To further explore the cooling effect of a large river on surrounding urban areas, we conducted mobile measurements near the Yangtze River in Wuhan during a hot and humid summer day. This research examined the river cooling effect, determined the thresholds of the cooling and humidifying distance using a third-order polynomial method, assessed littoral heat stress at the pedestrian level and investigated the impact of the littoral built environment using stepwise regression analysis. The results revealed that (1) the cooling and humidifying effect of the river was up to 3.55 °C, 1741 m and 17.25%, 1369 m in the daytime, which was much greater than that at night; (2) the river significantly mitigated pedestrian heat stress within 1200 m from the riverbank in the daytime, but showed a weak negative effect at night; (3) the built environment has a significant impact on the littoral areas, e.g., urban greening during the daytime and building morphology at night. The findings of this study provide empirical evidence for the cooling effect of a large river in urban areas and further support climate-sensitive planning and design for our thermal environment

    Multi-modal Imaging of Retinal Capillary Hemangioblastoma

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    Retinal capillary hemangioblastoma is the most frequent and earliest manifestation of Von Hippel Lindau disease, though they can be an isolated finding without systemic involvement. Although peripheral lesions are most common, juxtapapillary lesions are found in 11 to 15% of cases and can mimic pseudopapilledema, papillitis, or choroidal neovascular membrane. Here we present a case of retinal capillary hemangioblastoma masquerading as pseudopapilledema
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