630 research outputs found

    The Potential Economic Impact of Avian Flu Pandemic on Taiwan

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    This study analyzes the potential consequences of an outbreak of avian influenza (H5N1) on TaiwanĀ”Ā¦s macro economy and individual industries. Both the Input-Output (IO) Analysis Model and Computable General Equilibrium (CGE) Model are used to simulate the possible damage brought by lowering domestic consumption, export, and labor supply. The simulation results indicates that if the disease is confined within the poultry sector, then the impact on real GDP is around -0.1%~-0.4%. Once it becomes a human-to-human pandemic, the IO analysis suggests that the potential impacts on real GDP would be as much as -4.2%~-5.9% while labor demand would decrease 4.9%~6.4%. In the CGE analysis, which allows for resource mobility and substitutions through price adjustments, the real GDP and labor demand would contract 2.0%~2.4% and 2.2%~2.4%, respectively, and bringing down consumer prices by 3%. As for the individual sector, the outbreak will not only damage the poultry sector and its upstream and downstream industries, but also affect the service sectors including wholesale, retail, trade, air transportation, restaurants, as well as healthcare services. These results can be used to support public investment in animal disease control measures.Avian Flu Pandemic, Input-output Model, Computable General Equilibrium Model, Livestock Production/Industries,

    Oxygen vacancy engineering of Bi2O3/Bi2O2CO3 heterojunctions: Implications of the interfacial charge transfer, NO adsorption and removal

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    Efficient enrichment of targeted gaseous pollutants and fast diffusion rates of charge carriers are essential for the photocatalytic removal of nitric oxides at ambient concentration levels. Here we demonstrate that the construction of nano-structured Bi2O3/Bi2O2CO3 heterojunctions with oxygen vacancies, increasing the photocatalytic NO removal activity, durability and selectivity for final products nitrate formation. Combining the experimental and density-functional theory calculations, it was elucidated that the presence of surface oxygen vacancies not only work as adsorption sites of low concentration NO, but also offer an intimate and integrated structure between surface defects and the light-harvesting heterojunctions, which can facilitate solar energy conversion and charge carrier transfer (more than 2 times). Control experiments with pristine Bi2O3/Bi2O2CO3 also confirmed the crucial role of surface oxygen vacancies on the improvement of NO adsorption and removal ability during the photocatalytic degradation process. We explain the enhanced removal of NO through the synergistic effect of oxygen vacancy and heterojunction, which not only guaranteed the generation of more center dot OH radicals, but also provided another route to produce hydrogen peroxide. Our findings may provide an opportunity to develop a promising catalyst for air pollution control

    Dominant Influence of Biomass Combustion and Cross-Border Transport on Nitrogen-Containing Organic Compound Levels in the Southeastern Tibetan Plateau

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    The Tibetan Plateau (TP) is highly susceptible to climate change and the nitrogen-containing organic compounds (NOCs) in fine particulate matter (PM2.5) represent one of the large uncertainties in affecting the climate in high-altitude areas. Previous studies have shown that NOCs play a vital role in the nitrogen budget of PM2.5. However, our understanding of the composition and sources of NOCs in PM2.5, particularly in TP, is limited. Here, we aim to enhance our understanding of NOCs in the TP region by examining their identification, concentration levels, sources, and origins. We conducted field sampling at a regional background sampling site in Gaomeigu, in the southeastern margin of TP from March 11th to May 13th in 2017. The daily mass concentrations of NOCs ranged from 714.4 to 3887.1 ng m-3, with an average of (2119.4 ± 875.0 ng m-3) during the campaign. This average concentration was approximately 40 % higher than that reported at a typical regional site in the North China Plain (NCP), highlighting a more significant presence of NOCs in the Tibetan area. Biomass burning and secondary sources were identified as the major contributors to total NOCs. This was further substantiated by a regional air quality model, which indicated that over 80 % of the aerosol in the southeast of TP originated from neighboring countries. This study enhances our understanding of NOCs’ contribution to PM2.5 in TP and their potential impacts on the climate stability in high-altitude areas

    Synthesis of a Bi2O2CO3/ZnFe2O4 heterojunction with enhanced photocatalytic activity for visible light irradiation-induced NO removal

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    Although bismuth subcarbonate (Bi2O2CO3), a member of the Aurivillius-phase oxide family, is a promising photocatalyst for the removal of gaseous NO at parts-per-billion level, the large band gap of this material restricts its applications to the UV light region. The above problem can be mitigated by heterojunction fabrication, which not only broadens the light absorbance range, but also inhibits the recombination of photogenerated charge carriers. Herein, we implement this strategy to fabricate a novel Bi2O2CO3/ZnFe2O4 photocatalyst for NO removal under visible light irradiation and authenticate the formation of the above p-n heterojunction using an array of analytical techniques. Notably, the above composite showed activity superior to those of its individual constituents, and the underlying mechanisms of this activity enhancement were probed by density functional theory calculations and photocurrent measurements. Elevated electron/hole separation efficiency caused by the presence of an internal electric field at the Bi2O2CO3/ZnFe2O4 interface was identified as the main reason of the increased photocatalytic activity, with the main active species were determined as center dot O-2(-) and center dot OH by electron spin resonance spectroscopy. Finally, cytotoxicity testing proved the good biocompatibility of Bi2O2CO3/ZnFe2O4. Thus, this work presents deep insights into the preparation and use of a green p-n heterojunction catalyst in various applications

    Seasonal variations of anhydrosugars in PM2.5 in the Pearl River Delta Region, China

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    Anhydrosugars including levoglucosan and mannosan are the most effective organic tracers for biomass burning aerosol in the atmosphere. In this study, to investigate the contribution of biomass burning emissions to the aerosol burden in the Pearl River Delta (PRD) region, China, 24-hour integrated PM2.5 samples were collected simultaneously at four locations, (i) Guangzhou (GZ), (ii) Zhaoqing (ZQ) in Guangdong province, (iii) Hok Tsui (HT) and (iv) Hong Kong Polytechnic University (PU) in Hong Kong, in four seasons between 2006 and 2007. Levoglucosan and mannosan, together with water-soluble inorganic ions and water-soluble organic carbon (WSOC), were determined to elucidate the seasonal and spatial variations in biomass burning contributions. The concentrations of levoglucosan and mannosan were on average 82.4Ā±123 and 5.8Ā±8.6 ng māˆ’3, respectively. The WSOC concentrations ranged from 0.2 to 9.4 Āµg māˆ’3, with an average of 2.1Ā±1.6 Āµg māˆ’3. The relative contributions of biomass burning emissions to OC were 33% in QZ, 12% in GZ, 4% at PU and 5% at HT, respectively, estimated by the measured levoglucosan to organic carbon ratio (LG/OC) relative to literature-derived LG/OC values. The contributions from biomass burning emissions were in general 1.7ā€“2.8 times higher in winter than those in other seasons. Further, it was inferred from diagnostic tracer ratios that a significant fraction of biomass burning emissions was derived from burning of hard wood and likely also from field burning of agricultural residues, such as rice straw, in the PRD region. Our results highlight the contributions from biomass/biofuel burning activities on the regional aerosol budget in South China

    The modulation of hypoxia-inducible factor-1Ī±/plasminogen activator inhibitor-1 axis in human gingival fibroblasts stimulated with cyclosporine A

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    Background/PurposeThe prominent side effect of the immunosuppressive drug cyclosporine A (CsA) is gingival overgrowth. Hypoxia-inducible factor (HIF)-1Ī± regulates a wide variety of profibrogenic genes, which are closely associated with tissue fibrosis. The aim of this study was to compare HIF-1Ī± expression in normal gingival tissues and CsA-induced gingival overgrowth specimens and further explore the potential mechanisms that may lead to induction of HIF-1Ī± expression.MethodsFifteen CsA-induced gingival overgrowth specimens and five normal gingival tissues were examined by immunohistochemistry. Western blot was used to investigate the effects of CsA on the expression of HIF-1Ī± in cultured human gingival fibroblasts. The effects of CsA on plasminogen activator inhibitor (PAI)-1 expression were evaluated in environmental hypoxia.ResultsHIF-1Ī± staining in gingival tissue was stronger in CsA-induced gingival overgrowth group than normal gingival group (pĀ <Ā 0.05). The expression of HIF-1Ī± was significantly higher in CsA-induced gingival overgrowth specimens with higher levels of inflammatory infiltrates (pĀ =Ā 0.041). CsA was found to upregulate HIF-1Ī± protein in a dose-dependent manner (pĀ <Ā 0.05). Hypoxia increased CsA-induced PAI-1 protein expression than normoxic conditions (pĀ <Ā 0.05).ConclusionThese results suggest that HIF-1Ī± expression is significantly upregulated in CsA-induced gingival overgrowth specimens. The activation of HIF-1Ī± may promote fibrogenesis by an increase of PAI-1 expression and a subsequent elevation of extracellular matrix production in gingival tissues

    SOHSite: incorporating evolutionary information and physicochemical properties to identify protein S-sulfenylation sites

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    Distribution of KEGG pathway annotations for S-sulfenylated proteins. (DOCX 15ƂĀ kb
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