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Methylmercury and sulfate-reducing bacteria in mangrove sediments from Jiulong River Estuary,China

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Journal of Environmental Sciences 2011年第1期23卷 14-21页

作者： Hao Wu Zhenhua Ding Yang Liu Jinling Liu Haiyu Yan Jiayong Pan Liuqiang Li Huina Lin Guanghui Lin Haoliang Lu Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems and School of Life Sciences Xiamen University Xiamen 361005 China State Key Laboratory of Environmental Geochemistry Institute of Geochemistr) Chinese Aeademy of Sciences Guiyang 550002 China Key Laboratory of Nuclear Resources and Environment East China Institute of Technology Minist~ of Education Nanchang 330013 China

Estuaries are important sites for mercury （Hg） methylation, with sulfate-reducing bacteria （SRB） thought to be the main Hg methylators. Distributions of total mercury （THg） and methylmercury （MeHg） in mangrove sediment and sediment core from Jiulong River Estuary Provincial Mangrove Reserve, China were determined and the possible mechanisms of Hg methylation and their controlling factors in mangrove sediments were investigated. Microbiological and geochemical parameters were also determined. Results showed that SRB constitute a small fraction of total bacteria （TB） in both surface sediments and the profile of sediments. The content of THg, MeHg, TB, and SRB were （350 ± 150） ng/g, （0.47 ± 0.11） ng/g, （1.4× 10^011 ± 4.1 × 10^9） cfu/g dry weight （dw）, and （5.0× 10^6 d： 2.7 × 10^6） cfu/g dw in surficial sediments, respectively, and （240 ± 24） ng/g, （0.30 ± 0.15） ng/g, （1.9 × 10^11 ± 4.2 × 10^9） cfu/g dw, and （1.3 × 10^6 ± 2.0 × 10^6） cfu/g dw in sediment core, respectively. Results showed that THg, MeHg, TB, MeHg/THg, salinity and total sulfur （TS） increased with depth, but total organic matter （TOM）, SRB, and pH decreased with depth. Concentrations of MeHg in sediments showed significant positive correlation with THg, salinity, TS, and MeHg/THg, and significant negative correlation with SRB, TOM, and pH. It was concluded that other microbes, rather than SRB, may also act as main Hg methylators in mangrove sediments.

关键词： mercury methylmercury sediment mangrove sulfate-reducing bacteria

Flexible thermoregulatory microcapsule/polyurethane-MXene composite films with multiple thermal management functionalities and excellent EMI shielding performance

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Journal of Materials Science & technology 2023年第34期165卷 27-38页

作者： Danyuan Huang Ying Chen Li Zhang Xinxin Sheng Department of Polymeric Materials and Engineering School of Materials and EnergyGuangdong University of TechnologyGuangzhou510006China guangdong Provincial Key Laboratory of Functional Soft Condensed Matter Guangdong University of TechnologyGuangzhou510006China

The development of miniaturized,flexible,and portable electronic devices has led to an increasing demand for multifunctional flexible films that can provide temperature regulation,electromagnetic interference(EMI)shielding,and thermal *** this study,a novel hierarchical multifunctional flexible composite film is *** first step involves the synthesis of phase change microcapsule(PCMC)latex through in-situ ***,PCMC and waterborne polyurethane(WPU)latex were mixed and dried using a binary colloidal approach to produce a flexible composite phase change film(WPU/PCMC)with complete anti-leakage and satisfying melting enthalpy(147.86 J g^(-1)).To enhance the EMI performance and mechanical strength,a thin layer of antioxidant MXene@poly tannin acid(PTA)was directly sprayed onto the surface of WPU/PCMC,resulting in the WPU/PCMC/MXene@PTA film(WPM).Consequently,the WPM displays exceptional thermal management performance for multiple drives and outstanding EMI performance(56.86 dB),making it an ideal candidate for future multifunctional products.

关键词： Flexibility,Microcapsules Composite film Thermal management EMI shielding

Pt-Ni nanourchins as electrocatalysts for oxygen reduction reaction

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Frontiers in Energy 2017年第3期11卷 254-259页

作者： Qiaowan CHANG Yuan XU Shangqian ZHU Fei XIAO Minhua SHAO Department of Chemical and Biomolecular Engineering Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong China Department of Chemical and Biomolecular Engineering Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong China Energy Institute Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong China

Pt-Ni bimetallic alloys with various nanos-tructures have shown excellent activity toward oxygen reduction reaction （ORR）. The ORR activity is highly dependent on the structure of the catalyst. In this paper, Pt-Ni nanourchins were synthesized with an average size of 50 nm consisting of 10-20 nanorods and nanooctahedra by adjusting the synthesis condition. The formation of Pt-Ni nanourchins is mainly dependent on the adding order of solvents （benzyl ether, oleylamine and oleic acid）. Pt-Ni nanourchins present a reasonable high ORR activity （0.81 A/mg at 0.9 V）.

关键词： Pt-Ni alloys nanourchins oxygen reduction reaction shape control fuel cells

Neural-network adaptive controller for nonlinear systems and its application in pneumatic servo systems

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控制理论与应用（英文版） 2008年第1期6卷 97-103页

作者： Lu LU Fagui LIU Weixiang SHI Department of Computer Science and Engineering South China University of Technology Guangzhou Guangdong 510640 China Department of Mechaelectronics Engineering Xi＇an Jiaotong University Xi＇an Shanxi 710049 China

In this paper, a novel control law is presented, which uses neural-network techniques to approximate the affine class nonlinear system having unknown or uncertain dynamics and noise disturbances. It adopts an adaptive control law to adjust the network parameters online and adds another control component according to H-infinity control theory to attenuate the disturbance. This control law is applied to the position tracking control of pneumatic servo systems. Simulation and experimental results show that the tracking precision and convergence speed is obviously superior to the results by using the basic BP-network controller and self-tuning adaptive controller.

关键词： Nonlinear control Convergence Adaptive control H-infinity control Neural networks Pneumatic servo system

A Unified Framework for Multilingual Text-to-Speech Synthesis with SSML Specification as Interface

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Tsinghua Science and technology 2009年第5期14卷 623-630页

作者：吴志勇曹光琦蒙美玲蔡莲红 Department of Systems Engineering and Engineering Management The Chinese University of Hong KongShatinN.T. Tsinghua-CUhk Joint Research Center for Media Sciences Technologies and SystemsGraduate School at ShenzhenTsinghua University

This paper describes the design of a unified framework for a multilingual text-to-speech （TTS） synthesis engine - Crystal. The unified framework defines the common TTS modules for different languages and/or dialects. The interfaces between consecutive modules conform to the speech synthesis markup language （SSML） specification for standardization, interoperability, multilinguality, and extensibility. Detailed module divisions and implementation technologies for the unified framework are introduced, together with possible extensions for the algorithm research and evaluation of the TTS synthesis. Implementation of a mixed-language TTS system for Chinese Putonghua, Chinese Cantonese, and English demonstrates the feasibility of the proposed unified framework.

关键词： text-to-speech (TTS) synthesis multilingual unified framework speech synthesis markup language (SSML)

Hot deformation behavior of Cu-bearing antibacterial titanium alloy

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Journal of Materials Science & technology 2018年第10期34卷 1867-1875页

作者： Zheng Ma Ling Ren M.Babar Shahzad Rui Liu Ying Zhao Ke Yang Institute of Metal Research Chinese Academy of Sciences Center for Human Tissues and Organs Degeneration Shenzhen Institute of Advanced Technology Chinese Academy of Science

We investigated the deformation behavior of a new biomedical Cu-bearing titanium alloy （Ti-645 （Ti-6.06AI-3.75V-4.85Cu, in wt%）） to optimize its microstructure control and the hot-working process. The results showed that true stress-true strain curve ofti-645 alloy was susceptible to both deformation tem-perature and strain rate. The microstructure of Ti-645 alloy was significantly changed from equiaxed grain to acicular one with the deformation temperature while a notable decrease in grain size was recorded as well. Dynamic recovery （DRV） and dynamic recrystallization （DRX） obviously existed during the thermal compression of Ti-645 alloy. The apparent activation energies in （α ＋ β） phase and β single phase regions were calculated to be 495.21 kJ mo1^-1 and 195.69 kJ mo1^-1, respectively. The processing map showed that the alloy had a large hot-working region whereas the optimum window occurred in the strain rate range of 0.001-0.1 s-1, and temperature range of 900-960℃ and 1000-1050℃. The obtained results could provide a technological basis for the design of hot working procedure of Ti-645 alloy to optimize the material design and widen the ootential application of Ti-645 alloy in clinic.

关键词： cu-bearing titanium alloy Constitutive equation Thermal deformation Microstructure Processing map

In vitro and in vivo antibacterial activity of graphene oxidemodified porous TiO_(2) coatings under 808-nm light irradiation

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Rare Metals 2022年第2期41卷 540-545页

作者： Mao-Zhou Chai Mei-Wen An Xiang-Yu Zhang Paul-KChu College of Biomedical Engineering Taiyuan University of TechnologyTaiyuan 030024China Laboratory of Biomaterial Surfaces&Interfaces Institute of New Carbon MaterialsTaiyuan University of TechnologyTaiyuan 030024China Shanxi Key Laboratory of Bone and Soft Tissue Injury Repair Department of OrthopedicsSecond Hospital of Shanxi Medical UniversityTaiyuan 030024China Department of Physics Department of Materials Science and Engineeringand Department of Biomedical EngineeringCity University of Hong KongKowloonHong Kong 999077China

Bio-inertness and post-surgery infection on titanium(Ti)are the main causes of failure of biomedical implants in ***-infrared(NIR)photoactivated antibacterial therapy including photothermal and photodynamic therapies has attracted increasing attention due to the high bactericidal efficiency and little side *** micro-arc oxidation(MAO)is an effective method to improve the biological activity of Ti implants,the porous TiO_(2)coatings prepared by MAO do not respond to near-infrared(NIR)light to kill bacteria by the photothermal and photodynamic *** this work,graphene oxide(GO)-modified TiO_(2)coatings(TiO_(2)/GO)are prepared on Ti to improve the photothermal and photodynamic ability of the MAO *** TiO_(2)/GO coatings exhibit excellent antibacterial activity both in vitro and in vivo against Streptococcus mutans(***)under 808-nm NIR light irradiation due to the synergistic effects rendered by hyperthermia and reactive oxygen species(ROS).The NIR light-responsive antibacterial MAO coatings have large potential in combating implant-associated infections in clinical applications.

关键词： Antibacterial activity Graphene oxide(GO) Porous TiO_(2)coating Photo-therapy

Carboxyl Ester Lipase Protects Against Metabolic Dysfunction-Associated Steatohepatitis by Binding to Fatty Acid Synthase

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Engineering 2024年第10期41卷 204-215页

作者： Yang Song Wei Zhong Harry Cheuk-Hay Lau Yating Zhang Huayu Guan Mingxu Xie Suki Ha Diwen Shou Yongjian Zhou Hongzhi Xu Jun Yu Xiang Zhang Department of Medicine and Therapeutics Institute of Digestive DiseaseState Key Laboratory of Digestive DiseaseLi Ka Shing Institute of Health SciencesThe Chinese University of Hong KongHong Kong 999077China Shenzhen Research Institute The Chinese Unviersity of Hong KongShenzhen 518057China Department of Gastroenterology&Institute for Microbial Ecology&Xiamen Key Laboratory of Intestinal Microbiome and Human Health&Clinical Research Center for Gut Microbiota and Digestive Diseases of Fujian Province Zhongshan Hospital of Xiamen UniversitySchool of MedicineXiamen UniversityXiamen 361004China Division of Gastroenterology and Hepatology Renji HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200025China Department of Gastroenterology and Hepatology Guangzhou Digestive Disease CenterGuangzhou First People’s HospitalGuangzhou 510180China

Carboxyl ester lipase(CEL),a pivotal enzyme involved in lipid metabolism,is recurrently mutated in obese ***,we aimed to elucidate the functional significance,molecular mechanism,and therapeutic potential of CEL in metabolic dysfunction-associated steatohepatitis(MASH).Hepatocyte-specific carboxyl ester lipase gene(Cel)knockout(Cel^(DHEP))and wildtype(WT)littermates were fed with cholinedeficient high-fat diet(CD-HFD)for 16 weeks,or methionine-and choline-deficient diet(MCD)for three weeks to induce *** chromatography–mass spectrometry and co-immunoprecipitation were employed to identify the downstream targets of ***-HFD/MCD-fed WT mice received intravenous injections of CEL-adeno-associated viral,serotype 8(AAV8)to induce specific overexpression of CEL in the *** observed a decrease in CEL protein levels in MASH induced by CD-HFD or MCD in ***^(DHEP) mice fed with CD-HFD or MCD exhibited pronounced hepatic steatosis,inflammation,lipid peroxidation,and liver injury compared to WT littermates,accompanied by increased hepatic nuclear factor kappa-light-chain-enhancer of activated B cell(NF-jB)***,Cel knockdown in mouse primary hepatocytes and AML12 cells aggravated lipid accumulation and inflammation,whereas CEL overexpression exerted the opposite ***,CEL directly bound to fatty acid synthase(FASN),resulting in reduced FASN SUMOylation,which in turn promoted FASN degradation through the proteasome ***,inhibition of FASN ameliorated hepatocyte lipid accumulation and inflammation induced by Cel knockdown in vivo and in ***-specific CEL overexpression using AAV8-Cel significantly mitigated steatohepatitis in mice fed with CD-HFD or *** protects against steatohepatitis development by directly interacting with FASN and suppressing its expression for de novo *** overexpression confers a therapeutic benefit in steatohepatitis.

关键词： Metabolic dysfunction-associated steatohepatitis Carboxyl ester lipase Fatty acid synthase De novo lipogenesis Treatment

Dipyridyl Azo Compound 4,4'-Azopyridine as a Potential Coating Material for Toilet Sanitizer

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Chemical Research in Chinese Universities 2023年第6期39卷 864-869页

作者： WANG Qiwei JIANG Lu LAM Pik-Ling CHUI Chung-Hin WONG Wai-Yeung Antibiotics Research and Reevaluation Key Laboratory of Sichuan Province Sichuan Industrial Institute of AntibioticsChengdu UniversityChengdu 610052P.R.China Department of Applied Biology and Chemical technology The Hong Kong Polytechnic UniversityHung HomHong KongP.R.China Research and Development Division One Health International LimitedHong KongP.R.China

Good toilet hygiene can reduce the risk of pathogenic *** flushing,pathogenic bacteria can be spread by the water droplets,especially in the toilet *** coli(***)is one of the frequently occurring Gram-negative bacterial pathogens found in the toilet *** this study,we investigated the potential *** activity of some azobenzene *** them,compound 2,with the heterocyclic nitrogen in both phenyl rings,showed the strongest antibacterial effect on ***,with the minimum inhibitory concentration of 80μg/mL and the minimum bactericidal concentration of 320μg/*** 2 displayed a comparative zone of clearance[(14.50±2.29)mm]to that of ampicillin[(13.17±1.76)mm].The reactive oxygen species(ROS)assay suggested that compound 2 might induce the loss of bacteria via the oxidative stress by eliciting the generation of intracellular *** further examined the potential cytotoxicity of compound 2 to the human skin HaCaT *** 2-treated skin cells showed a good maintenance of cellular morphology and a clear definition of cell nuclei,with a satisfactory cell viability(ca.90%)at 80μg/***,compound 2 would be a possible antibacterial coating agent for the surface sanitizer of the toilet seats to inhibit the growth of ***.

关键词： Antibacterial Azobenzene Escherichia coli Skin cytotoxicity Toilet seat