715 research outputs found

    A Study of Sexuality and Gender in M. Butterfly Under the Context of Post-Colonial Feminism

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    David Henry Hwang’s M. Butterfly is a reinterpretation of the classic opera Madama Butterfly. He intends to expose to the readers the profound ideological imprints of racism, colonialism and patriarchy contained in Puccini’s oriental fantasy love tragedy, and to extend the discussion of such propositions as gender discrimination, racial prejudice, western misreading of the East and cultural hegemony that still exist in today’s society. This play serves as a vivid profiling of the particular historical situation suffered by Asians in the American racist environment. It is also progressive in that it challenges the stereotypes of Oriental women in Western literature. However, there is no denying that the deconstruction of colonialism and patriarchy in M. Butterfly is incomplete and inadequate. Taking a post-colonial feminist perspective as an entry point, this paper tries to analyze the orientalist colonial elements presented in M. Butterfly and focus on the sexuality and gender issues of the two main characters, Song Liling and Gallimard, hoping to help readers break out of the established framework and have a new understanding of the relationship between the West and the East, and between men and women.

    Enantiocomplementary synthesis of chiral alcohols combining photocatalysis and whole-cell biocatalysis in a one-pot cascade process

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    As a powerful tool in synthetic organic chemistry, photocatalysis has the features of green, better atom economy, and mild conditions [1-2]. Recently, some cascade reaction protocols have been properly designed by combining photocatalysis and biocatalysis[3-4]. For example, Zhao and Hartwig reported an asymmetric reaction which coupled photocatalysts for E/Z isomerization of alkenes with ene-reductases for the reduction of carbon–carbon double bonds, to generate valuable enantioenriched products [5], which achieved the dual-advantages of both photocatalysis and biocatalysis. We envisioned a photochemo-enzymatic one-pot whole-cell process to convert a series of carboxylic acids into corresponding chiral alcohols with good yields (up to 93%) and excellent stereoselectivity (up to 99% ee). The photocatalysis step was conducted in aqueous phase by using O2 as oxidant and the following whole cell bioreduction without the addition of the expensive cofactor NADPH was a much milder and more efficient approach to obtain chiral alcohols. All these advantages indicate that the photochemo-enzymatic one-pot transformation may have great potential in green synthetic chemistry. Please click Additional Files below to see the full abstract

    GENERATION OF CRACKS IN HIGHWAY EMBANKMENT ON BLACK COTTON SOIL

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    This research revealed the crack generation of the highway embankment from the water losing shrinkage of the wet black cotton soil (BCS), which is a type of soil with high swell-shrink potential. The road seepage meter was used to test the permeability of filling materials, which was used to replace BCS. The moisture content and embankment deflection of BCS foundation were measured after the rainy season. Based on the coupled consolidation theory for unsaturated soil, the change in additional tension stress of the embankment induced by water loss shrinkage of BCS was simulated by Abaqus. The results indicated that the rainfall seeped into the foundation through highly permeable refill materials to result in BCS expansion and decrease the embankment strength. After the rainy season, the additional tensile stress caused by water loss shrinkage of BCS induces cracking of highway embankment, and the maximum cracking depth often appears at the shoulder of highway. The deep and wide cracks are easy to appear in the low embankment constructed on a thick BCS foundation under strong evaporation

    Successive Vaccination and Difference in Immunity of a Delay SIR Model with a General Incidence Rate

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    A delay SIR epidemic model with difference in immunity and successive vaccination is proposed to understand their effects on the disease spread. From theorems, it is obtained that the basic reproduction number governs the dynamic behavior of the system. The existence and stability of the possible equilibria are examined in terms of a certain threshold condition about the basic reproduction number. By use of new computational techniques for delay differential equations, we prove that the system is permanent. Our results indicate that the recovery rate and the vaccination rate are two factors for the dynamic behavior of the system. Numerical simulations are carried out to investigate the influence of the key parameters on the spread of the disease, to support the analytical conclusion, and to illustrate possible behavioral scenarios of the model

    Successive Vaccination and Difference in Immunity of a Delay SIR Model with a General Incidence Rate

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    A delay SIR epidemic model with difference in immunity and successive vaccination is proposed to understand their effects on the disease spread. From theorems, it is obtained that the basic reproduction number governs the dynamic behavior of the system. The existence and stability of the possible equilibria are examined in terms of a certain threshold condition about the basic reproduction number. By use of new computational techniques for delay differential equations, we prove that the system is permanent. Our results indicate that the recovery rate and the vaccination rate are two factors for the dynamic behavior of the system. Numerical simulations are carried out to investigate the influence of the key parameters on the spread of the disease, to support the analytical conclusion, and to illustrate possible behavioral scenarios of the model

    Bartter syndrome type III with glomerular dysplasia and chronic kidney disease: A case report

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    BackgroundBartter syndrome (BS) type III is a rare autosomal recessive genetic disease. Its clinical features are polyuria, hypokalemia, hypochloremia, metabolic alkalosis, and hyperreninaemia. A few BS type III can be complicated with chronic kidney disease.Case presentationWe report a 14-year-old boy with Bartter syndrome caused by a c.1792C > T (p.Q598*) mutation in the CLCNKB gene. He was a no deafness and full-term baby, and he had renal dysplasia and chronic kidney disease (CKD). In addition, we summarize all cases of BS type III complicated with CKD.ConclusionsWe report a case of Bartter syndrome complicated by chronic kidney disease caused by a new mutation of CLCNKB. As we all know, BS type IV is usually combined with chronic kidney disease, and BS type III can also integrate with CKD. We don't find BS type III with glomerular dysplasia in the literature. So renal damage in BS type III is not only FSGS; clinicians must also be aware of glomerular dysplasia

    De novo sequencing and analysis of the American ginseng root transcriptome using a GS FLX Titanium platform to discover putative genes involved in ginsenoside biosynthesis

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    <p>Abstract</p> <p>Background</p> <p>American ginseng (<it>Panax quinquefolius </it>L.) is one of the most widely used herbal remedies in the world. Its major bioactive constituents are the triterpene saponins known as ginsenosides. However, little is known about ginsenoside biosynthesis in American ginseng, especially the late steps of the pathway.</p> <p>Results</p> <p>In this study, a one-quarter 454 sequencing run produced 209,747 high-quality reads with an average sequence length of 427 bases. <it>De novo </it>assembly generated 31,088 unique sequences containing 16,592 contigs and 14,496 singletons. About 93.1% of the high-quality reads were assembled into contigs with an average 8-fold coverage. A total of 21,684 (69.8%) unique sequences were annotated by a BLAST similarity search against four public sequence databases, and 4,097 of the unique sequences were assigned to specific metabolic pathways by the Kyoto Encyclopedia of Genes and Genomes. Based on the bioinformatic analysis described above, we found all of the known enzymes involved in ginsenoside backbone synthesis, starting from acetyl-CoA via the isoprenoid pathway. Additionally, a total of 150 cytochrome P450 (CYP450) and 235 glycosyltransferase unique sequences were found in the 454 cDNA library, some of which encode enzymes responsible for the conversion of the ginsenoside backbone into the various ginsenosides. Finally, one CYP450 and four UDP-glycosyltransferases were selected as the candidates most likely to be involved in ginsenoside biosynthesis through a methyl jasmonate (MeJA) inducibility experiment and tissue-specific expression pattern analysis based on a real-time PCR assay.</p> <p>Conclusions</p> <p>We demonstrated, with the assistance of the MeJA inducibility experiment and tissue-specific expression pattern analysis, that transcriptome analysis based on 454 pyrosequencing is a powerful tool for determining the genes encoding enzymes responsible for the biosynthesis of secondary metabolites in non-model plants. Additionally, the expressed sequence tags (ESTs) and unique sequences from this study provide an important resource for the scientific community that is interested in the molecular genetics and functional genomics of American ginseng.</p

    Efficient wide-bandgap perovskite solar cells with open-circuit voltage deficit below 0.4 V via hole-selective interface engineering

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    Wide-bandgap mixed-halide perovskite solar cells (WBG-PSCs) are promising top cells for efficient tandem photovoltaics to achieve high power conversion efficiency (PCE) at low cost. However, the open-circuit voltage (VOC) of WBG-PSCs is still unsatisfactory as the VOC-deficit is generally larger than 0.45 V. Herein, we report a buried interface engineering strategy that substantially improves the VOC of WBG-PSCs by inserting amphophilic molecular hole-selective materials featuring with a cyanovinyl phosphonic acid (CPA) anchoring group between the perovskite and substrate. The assembly and redistribution of CPA-based amphiphilic molecules at the perovskite-substrate buried interface not only promotes the growth of a low-defect crystalline perovskite thin film, but also suppresses the photo-induced halide phase separation. The energy level alignment between wide-bandgap perovskite and the hole-selective layer is further improved by modulating the substituents on the triphenylamine donor moiety (methoxyls for MPA-CPA, methyls for MePA-CPA, and bare TPA-CPA). Using a 1.68 eV bandgap perovskite, the MePA-CPA-based devices achieved an unprecedentedly high VOC of 1.29 V and PCE of 22.3% under standard AM 1.5 sunlight. The VOC-deficit (&lt;0.40 V) is the lowest value reported for WBG-PSCs. This work not only provides an effective approach to decreasing the VOC-deficit of WBG-PSCs, but also confirms the importance of energy level alignment at the charge-selective layers in PSCs.</p

    Scale effect of circularly polarized luminescent signal of matter

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    Circularly polarized luminescence (CPL) is an important part in the research of modern luminescent materials and photoelectric devices. Usually, chiral molecules or chiral structures are the key factors to induce CPL spontaneous emission. In this study, a scale-effect model based on scalar theory was proposed to better understand the CPL signal of luminescent materials. Besides chiral structures being able to induce CPL, achiral ordered structures can also have a significant influence on CPL signals. These achiral structures are mainly reflected in the particle scale in micro-order or macro-order, i.e. the CPL signal measured under most conditions depends on the scale of the ordered medium, and does not reflect the inherent chirality of the excited state of the luminescent molecule. This kind of influence is difficult to be eliminated by simple and universal strategies in macro-measurement. At the same time, it is found that the measurement entropy of CPL detection may be the key factor to determine the isotropy and anisotropy of the CPL signal. This discovery would bring new opportunities to the research of chiral luminescent materials. This strategy can also greatly reduce the development difficulty of CPL materials and show high application potential in biomedical, photoelectric information and other fields.</p

    Data Decomposition and Spatial Mixture Modeling for Part Based Model

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    Abstract. This paper presents a system of data decomposition and spa-tial mixture modeling for part based models. Recently, many enhanced part based models (with e.g., multiple features, more components or parts) have been proposed. Nevertheless, those enhanced models bring high computation cost together with the risk of over-fitting. To tackle this problem, we propose a data decomposition method for part based models which not only accelerates training and testing process but also improves the performance on average. Besides, the original part based model uses a strict rigid structural model to describe the distribution of each part location. It is not “deformable ” enough, especially for those instances with different viewpoints or poses in the same aspect ratio. To address this problem, we present a novel spatial mixture modeling method. The spatial mixture embedded model is then integrated into the proposed data decomposition framework. We evaluate our system on the challenging PASCAL VOC2007 and PASCAL VOC2010 datasets, demonstrating the state-of-the-art performance compared with other re-lated methods in terms of accuracy and efficiency.
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