Approach to Fungal Infections in Human Immunodeficiency Virus-Infected Individuals Pneumocystis and Beyond

Many fungi cause pulmonary disease in HIV-infected patients. Major pathogens include Pneumocystis jirovecii, Cryptococcus neoformans, Aspergillus species, Histoplasma capsulatum, Coccidioides species, Blastomyces dermatitidis, Paracoccidioides brasiliensis, Talaromyces marneffei, and Emmonsia species. Because symptoms are frequently non-specific, a high index of suspicion for fungal infection is required for diagnosis. Clinical manifestations of fungal infection in HIV-infected patients frequently depend on the degree of immunosuppression and the CD4 + TH cell count. Establishing definitive diagnosis is important because treatments differ. Primary and secondary prophylaxis depends on CD4+ TH cell counts as well as geographic location and local prevalence of disease

The conditional permutation test for independence while controlling for confounders

We propose a general new method, the conditional permutation test, for testing the conditional independence of variables $X$ and $Y$ given a potentially high-dimensional random vector $Z$ that may contain confounding factors. The proposed test permutes entries of $X$ non-uniformly, so as to respect the existing dependence between $X$ and $Z$ and thus account for the presence of these confounders. Like the conditional randomization test of Cand\`es et al. (2018), our test relies on the availability of an approximation to the distribution of $X \mid Z$. While Cand\`es et al. (2018)'s test uses this estimate to draw new $X$ values, for our test we use this approximation to design an appropriate non-uniform distribution on permutations of the $X$ values already seen in the true data. We provide an efficient Markov Chain Monte Carlo sampler for the implementation of our method, and establish bounds on the Type I error in terms of the error in the approximation of the conditional distribution of $X\mid Z$, finding that, for the worst case test statistic, the inflation in Type I error of the conditional permutation test is no larger than that of the conditional randomization test. We validate these theoretical results with experiments on simulated data and on the Capital Bikeshare data set

Content-aware photo collage using circle packing

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Effect of Al addition on the microstructure and electronic structure of HfO₂film

Author name used in this publication: P. F. LeeAuthor name used in this publication: J. Y. Dai2006-2007 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Boron neutron capture therapy induces apoptosis of glioma cells through Bcl-2/Bax

<p>Abstract</p> <p>Background</p> <p>Boron neutron capture therapy (BNCT) is an alternative treatment modality for patients with glioma. The aim of this study was to determine whether induction of apoptosis contributes to the main therapeutic efficacy of BNCT and to compare the relative biological effect (RBE) of BNCT, γ-ray and reactor neutron irradiation.</p> <p>Methods</p> <p>The neutron beam was obtained from the Xi'an Pulsed Reactor (XAPR) and γ-rays were obtained from [⁶⁰Co] γ source of the Fourth Military Medical University (FMMU) in China. Human glioma cells (the U87, U251, and SHG44 cell lines) were irradiated by neutron beams at the XAPR or [⁶⁰Co] γ-rays at the FMMU with different protocols: Group A included control nonirradiated cells; Group B included cells treated with 4 Gy of [⁶⁰Co] γ-rays; Group C included cells treated with 8 Gy of [⁶⁰Co] γ-rays; Group D included cells treated with 4 Gy BPA (p-borono-phenylalanine)-BNCT; Group E included cells treated with 8 Gy BPA-BNCT; Group F included cells irradiated in the reactor for the same treatment period as used for Group D; Group G included cells irradiated in the reactor for the same treatment period as used for Group E; Group H included cells irradiated with 4 Gy in the reactor; and Group I included cells irradiated with 8 Gy in the reactor. Cell survival was determined using the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium (MTT) cytotoxicity assay. The morphology of cells was detected by Hoechst33342 staining and transmission electron microscope (TEM). The apoptosis rate was detected by flow cytometer (FCM). The level of Bcl-2 and Bax protein was measured by western blot analysis.</p> <p>Results</p> <p>Proliferation of U87, U251, and SHG44 cells was much more strongly inhibited by BPA-BNCT than by irradiation with [⁶⁰Co] γ-rays (<it>P </it>< 0.01). Nuclear condensation was determined using both a fluorescence technique and electron microscopy in all cell lines treated with BPA-BNCT. Furthermore, the cellular apoptotic rates in Group D and Group E treated with BPA-BNCT were significantly higher than those in Group B and Group C irradiated by [⁶⁰Co] γ-rays (<it>P </it>< 0.01). The clonogenicity of glioma cells was reduced by BPA-BNCT compared with cells treated in the reactor (Group F, G, H, I), and with the control cells (<it>P </it>< 0.01). Upon BPA-BNCT treatment, the Bax level increased in glioma cells, whereas Bcl-2 expression decreased.</p> <p>Conclusions</p> <p>Compared with ��-ray and reactor neutron irradiation, a higher RBE can be achieved upon treatment of glioma cells with BNCT. Glioma cell apoptosis induced by BNCT may be related to activation of Bax and downregulation of Bcl-2.</p

Extensive degeneracy, Coulomb phase and magnetic monopoles in an artificial realization of the square ice model

Artificial spin ice systems have been introduced as a possible mean to investigate frustration effects in a well-controlled manner by fabricating lithographically-patterned two-dimensional arrangements of interacting magnetic nanostructures. This approach offers the opportunity to visualize unconventional states of matter, directly in real space, and triggered a wealth of studies at the frontier between nanomagnetism, statistical thermodynamics and condensed matter physics. Despite the strong efforts made these last ten years to provide an artificial realization of the celebrated square ice model, no simple geometry based on arrays of nanomagnets succeeded to capture the macroscopically degenerate ground state manifold of the corresponding model. Instead, in all works reported so far, square lattices of nanomagnets are characterized by a magnetically ordered ground state consisting of local flux-closure configurations with alternating chirality. Here, we show experimentally and theoretically, that all the characteristics of the square ice model can be observed if the artificial square lattice is properly designed. The spin configurations we image after demagnetizing our arrays reveal unambiguous signatures of an algebraic spin liquid state characterized by the presence of pinch points in the associated magnetic structure factor. Local excitations, i.e. classical analogues of magnetic monopoles, are found to be free to evolve in a massively degenerated, divergence-free vacuum. We thus provide the first lab-on-chip platform allowing the investigation of collective phenomena, including Coulomb phases and ice-like physics.Comment: 26 pages, 10 figure

Tuning of Human Modulation Filters Is Carrier-Frequency Dependent

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A contextualização como estruturante curricular na educação em ciências : uma discussão a partir dos documentos oficiaisbra sileiros e artigos especializados

As Diretrizes e Bases da Educação Nacional desencadearam políticas educacionais para a redefinição do Ensino Médio no Brasil. Como parte dessa política, os Parâmetros Curriculares Nacionais incorporam a contextualização como princípio curricular central. Empregando análise de conteúdo,analisamos artigos de periódicos que atribuem diferentes sentidos para a contextualização no Ensino de Ciências. Com a construção de categorias inspiradas na análise vigotskiana, dimensionamos o conteúdo da contextualização como sentido epistemológico/cognitivo, ético e híbridos destes dois.Encontramos a preponderância de um hibridismo entre uma contextualização que busca dar um sentido cognitivo ao conhecimento e uma contextualização que busca um sentido ético, articulação nem sempre presentes de forma explicita nos documentos oficiais