281 research outputs found

    Emergence of topological phases from the extension of two-dimensional lattice with nonsymmorphic symmetries

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    Young and Kane have given a great insight for 2D Dirac semimetals with nontrivial topology in the presence of nonsymmorphic crystalline symmetry. Based on one of 2D nonsymmorphic square lattice structures they proposed, we further construct a set of 3D minimal tight-binding models via vertically stacking the 2D nonsymmorphic lattice. Specifically, our model provides a platform to generate three topologically semimetallic phases such as Dirac nodal line semimetals, Weyl nodal line semimetals and Weyl semimetals. The off-centered mirror symmetry sufficiently protects nodal lines emerging within mirror-invariant plane with a nontrivial mirror invariant nMZn_{M\mathbb{Z}}, whereas twofold screw rotational symmetry protects nontrivial Weyl nodal points with topological charge C=2C=2. Interestingly, Weyl nodal loops are generated without mirror symmetry protection, where nontrivial "drumhead" surface states emerge within loops. In the presence of both time-reversal and inversion symmetries, the emergence of weak topological insulator phases is discussed as well.Comment: 8 pages, 6 figures and 1 tabl

    Electrodeposition of High-Functional Metal Oxide on Noble Metal for MEMS Devices

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    MEMS gas sensors could exert a significant impact on the automotive sector since future legislation is expected to stipulate the monitoring of NOx and unburned fuel gases in vehicle exhausts. Among the materials, zinc oxide and TiO2 are the most promising and extensively used materials for monitoring of NOx gas since zinc oxide and TiO2 show the high sensitivity, good stability, and fast response. Electrochemistry is a potential method to fabricate zinc oxide and TiO2 for the applications since it is carried out at relatively low temperature and can cooperate with photolithography, which is an important process in MEMS. This study integrated zinc oxide/gold-layered structure and TiO2/NiP hybrid structure on elastic fabrics, respectively, to realize an elastic gas sensor. Electroless plating (EP) and cathodic deposition were used to metallize and deposit metal oxides on elastic fabrics. Supercritical carbon dioxide (scCO2) was further introduced into the electrochemical process to enhance the composite reliability

    Evaluation of Ertapenem use with Impact Assessment on Extended-Spectrum Beta-Lactamases (ESBL) Production and Gram-Negative resistance in Singapore General Hospital (SGH)

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    BACKGROUND: Ertapenem (preferred choice for ESBL-producing organisms) use exhibited an increasing trend from 2006 to 2008. As extensive use of ertapenem might induce the mutation of resistant bacteria strains to ertapenem, we aimed to assess the appropriateness and impact of ertapenem-use, on ESBL production, the trends of gram-negative bacterial resistance and on the utilization of other antibiotics in our institution. METHODS: Inpatients who received a dose of ertapenem during 1 January 2006 to 31 December 2008, were reviewed. Pertinent patient clinical data was extracted from the pharmacy databases and assessed for appropriateness based on dose and indication. Relevant data from Network for Antimicrobial Resistance Surveillance (Singapore) (NARSS) was extracted, to cross-correlate with ertapenem via time series to assess its impact on hospital epidemiology, trends of gram-negative resistance and consumption of other antibiotics from 2006 to mid-2010. RESULTS: 906 cases were reviewed. Ertapenem therapy was appropriate in 72.4% (93.7% success rate). CNS adverse events were noted in 3.2%. Readmission rate (30-day) due to re-infection (same pathogen) was 5.5%. Fifty cases had cultures growing Pseudomonas aeruginosa within 30 days of ertapenem initiation, with 25 cases growing carbapenem-resistant Pseudomonas aeruginosa. Ertapenem use increased from 0.45 DDD/100 patient days in 2006 to 1.2 DDD/100 patient days in mid-2010. Overall, the increasing trend of ertapenem consumption correlated with 1) increasing incidence-densities of ciprofloxacin-resistant/cephalosporin-resistant E. coli at zero time lag; 2) increasing incidence-densities of ertapenem-resistant Escherichia. coli and Klebsiella spp. at zero time lag; 3) increasing incidence-density of carbapenem-resistant Pseudomonas aeruginosa, at zero time lag. Increasing ertapenem consumption was significantly correlated with decreasing consumption of cefepime (R(2) = 0.37344) 3 months later. It was significantly correlated with a decrease in imipenem consumption (R(2) = 0.31081), with no time lag but was correlated with subsequent increasing consumption of meropenem (R(2) = 0.4092) 6 months later. CONCLUSION: Ertapenem use was appropriate. Increasing Ertapenem consumption did not result in a decreasing trend of ESBL producing enterobacteriaceae and could result in the selection for multi-drug resistant bacteria

    Production of Active Nonglycosylated Recombinant B-Chain of Type-2 Ribosome-Inactivating Protein from Viscum articulatum and Its Biological Effects on Peripheral Blood Mononuclear Cells

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    Type-2 ribosome-inactivating proteins, composed of a toxic A-chain and lectin-like B-chain, display various biological functions, including cytotoxicity and immunomodulation. We here cloned the lectin-like B-chain encoding fragment of a newly identified type-2 RIP gene, articulatin gene, from Viscum articulatum, into a bacterial expression vector to obtain nonglycosylated recombinant protein expressed in inclusion bodies. After purification and protein refolding, soluble refolded recombinant articulatin B-chain (rATB) showed lectin activity specific toward galactoside moiety and was stably maintained while stored in low ionic strength solution. Despite lacking glycosylation, rATB actively bound leukocytes with preferential binding to monocytes and in vitro stimulated PBMCs to release cytokines without obvious cytotoxicity. These results implicated such a B-chain fragment as a potential immunomodulator

    Clinical Effects of Laser Acupuncture plus Chinese Cupping on the Pain and Plasma Cortisol Levels in Patients with Chronic Nonspecific Lower Back Pain: A Randomized Controlled Trial

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    Objectives. Chronic nonspecific lower back pain (LBP) is a common disease. Insufficient data is currently available to conclusively confirm the analgesic effects of laser acupuncture on LBP. This study evaluated the effectiveness of laser acupuncture plus Chinese cupping in LBP treatment. Methods. Patients with chronic nonspecific LBP were enrolled for a randomized controlled trial and assigned to the laser acupuncture group (laser acupuncture plus Chinese cupping) and control group (sham laser plus Chinese cupping). Laser acupuncture (808 nm; 40 mW; 20 Hz; 15 J/cm2) and Chinese cupping were applied on the Weizhong (BL40) and Ashi acupoints for 5 consecutive days. Plasma cortisol levels were assessed before and after the 5-day treatment session. The visual analog scale (VAS) scores were recorded at baseline and throughout the 5-day treatment session. Results. After the treatment session, the plasma cortisol levels and VAS scores decreased significantly in both groups. In the laser acupuncture group, the VAS scores decreased significantly on days 4 and 5, and an enhanced reduction in VAS scores was observed. Conclusion. Laser acupuncture plus Chinese cupping at the Weizhong (BL40) and Ashi acupoints effectively reduced pain and inflammation in chronic nonspecific LBP. This therapy could be a suitable option for LBP treatment in clinical settings

    Establishment of Asia-Pacific Network for Enterovirus Surveillance

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    Enteroviruses (EV), the major pathogens of hand, foot, and mouth disease (HFMD) and herpangina, affect millions of children each year. Most human enteroviruses cause self-limited infections except polioviruses, enterovirus A71 (EV-A71), enterovirus D68 (EV-D68), and several echoviruses (Echo) and coxsackieviruses (CV). Especially, EV-A71 has repeatedly caused large-scale outbreaks in the Asia-Pacific region since 1997. Some Asian countries have experienced cyclical outbreaks of severe EV-A71 infections and initiated development of EV-A71 vaccines. Five EV-A71 vaccine candidates have been clinically evaluated and three of them were approved for marketing in China. However, none of the China-approved products seek marketing approval in other countries. This situation supports a role for collaboration among Asian countries to facilitate clinical trials and licensure of EV-A71 vaccines. Additionally, enterovirus D68 outbreaks have been reported in the US and Taiwan currently and caused severe complications and deaths. Hence, an Asia-Pacific Network for Enterovirus Surveillance (APNES) has been established to estimate disease burden, understand virus evolution, and facilitate vaccine development through harmonizing laboratory diagnosis and data collection. Founded in 2017, the APNES is comprised of internationally recognized experts in the field of enterovirus in Asian countries working to raise awareness of this potentially fatal and debilitating disease. This article demonstrated the summaries of the first expert meeting, 2017 International Workshop on Enterovirus Surveillance and Vaccine Development, held by APNES in Taipei, Taiwan, March 2017

    Nationwide Surveillance of Influenza during the Pandemic (2009–10) and Post-Pandemic (2010–11) Periods in Taiwan

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    INTRODUCTION: Although WHO declared the world moving into the post-pandemic period on August 10, 2010, influenza A(H1N1) 2009 virus continued to circulate globally. Its impact was expected to continue during the 2010-11 influenza season. This study describes the nationwide surveillance findings of the pandemic and post-pandemic influenza periods in Taiwan and assesses the impact of influenza A(H1N1) 2009 during the post-pandemic period. METHODS: The Influenza Laboratory Surveillance Network consisted of 12 contract laboratories for collecting and testing samples with acute respiratory tract infections. Surveillance of emergency room visits and outpatient department visits for influenza-like illness (ILI) were conducted using the Real-Time Outbreak and Disease Surveillance system and the National Health Insurance program data, respectively. Hospitalized cases with severe complications and deaths were reported to the National Notifiable Disease Surveillance System. RESULTS: During the 2009-10 influenza season, pandemic A(H1N1) 2009 was the predominant circulating strain and caused 44 deaths. However, the 2010-11 influenza season began with A(H3N2) being the predominant circulating strain, changing to A(H1N1) 2009 in December 2010. Emergency room and outpatient department ILI surveillance displayed similar trends. By March 31, 2011, there were 1,751 cases of influenza with severe complications; 50.1% reported underlying diseases. Of the reported cases, 128 deaths were associated with influenza. Among these, 93 (72.6%) were influenza A(H1N1) 2009 and 30 (23.4%) A(H3N2). Compared to the pandemic period, during the immediate post-pandemic period, increased number of hospitalizations and deaths were observed, and the patients were consistently older. CONCLUSIONS: Reemergence of influenza A(H1N1) 2009 during the 2010-11 influenza season had an intense activity with age distribution shift. To further mitigate the impact of future influenza epidemics, Taiwan must continue its multifaceted influenza surveillance systems, remain flexible with antiviral use policies, and revise the vaccine policies to include the population most at risk
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