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Effect of humic acids and sunlight on the cytotoxicity of engineered zinc oxide and titanium dioxide nanoparticles to a river bacterial assemblage

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Journal of Environmental Sciences 2013年第9期25卷 1925-1935页

作者： Thabitha P.dasari Huey-Min Hwang Environmental Science ph.d. Program Jackson State University department of Biology Jackson State University

The effect of a terrestrial humic acid （HA） and Suwannee River HA on the cytotoxicity of engineered zinc oxide nanoparticles （ZnONPs） and titanium dioxide nanoparticles （TiO2NPs） to natural aquatic bacterial assemblages was measured with spread plate counting. The effect of HA （10 and 40 ppm） on the cytotoxicity of ZnONPs and TiO2NPs was tested factorially in the presence and absence of natural sunlight （light irradiation （LI））. The experiment was of full factorial, completely randomized design and the results were analyzed using the General Linear Model in SAS analytical software. The method of least squares means was used to separate the means or combinations of means. We determined the mechanism of toxicity via measurements of oxidative stress and metal ions. The toxicity of ZnONPs and TiO2NPs to natural aquatic bacterial assemblages appears to be concentration dependent. Moreover, the cytotoxicity of ZnONPs and TiO2NPs appeared to be affected by HA concentration, the presence of sunlight irradiation, and the dynamic multiple interactions among these factors. With respect to light versus darkness in the control group, the data indicate that bacterial viability was inhibited more in the light exposure than in the darkness exposure. The same was true in the HA treatment groups. With respect to terrestrial versus Suwanee River HA for a given nanoparticle, in light versus darkness, bacterial viability was more inhibited in the light treatment groups containing the terrestrial HA than in those containing Suwanee River HA. differences in the extent of reactive oxygen species formation, adsorption/binding of ZnONPs/TiO2NPs by HA, and the levels of free metal ions were speculated to account for the observed cytotoxicity. TEM images indicate the attachment and binding of the tested nanoparticles to natural bacterial assemblages. Besides the individual parameter, significant effects on bacterial viability count were also observed in the following combined treatments： HA-Zn

关键词： natural bacterial assemblages humic acid median lethal concentration (LC50 ) reactive oxygen species

On the formation of couplet-style stratifications

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International Journal of Sediment Research 2008年第1期23卷 85-91页

作者： Yu-Hai WANG1, Yan-Hong WANG2, and Li-Qun TANG31 ph.d., Engineer, department of Sediment Research, China Institute of Water Resources and Hydropower Research, Chegongzhuangxilu 20, Beijing 100044, China, 2 ph.d., Engineer, Nanjing Hydraulic Research Institute, Hujuguanlu 34, Nanjing 210024, China 3 ph.d., Prof., department of Sediment Research, China Institute of Water Resources and Hydropower Research, Chegongzhuangxilu 20, Beijing 100044, China [a]ph.d. Engineer department of Sediment Research China Institute of Water Resources and Hydropower Research Chegongzhuangxilu 20 Beijing 100044 China [b]ph.d. Engineer Nanjing Hydraulic Research Institute Hujuguanlu 34 Nanjing 210024 China [c]ph.d. Prof. department of Sediment Research China Institute of Water Resources and Hydropower Research Chegongzhuangxilu 20 Beijing 100044 China

Couplet-style stratifications refer to the sedimentary sequences that consist of alternating coarse-grain-dominated bed and fine-grain-dominated bed, with or without a sandwiched middle-sized bed. The formation mechanism is complicated due to the interplays of varying driving force (s), sediment supply & transport and topographic configurations. This paper presents a comprehensive overview of such characteristic bedforms, which emerge during the transport and deposition of non-uniform sediments. The leading formative models include water-stage variation, gravel-overpassing process, superimposition of bedload sheets and avalanching process (inverse grading). Each process might produce similar or distinct sedimentological features with respect to grading, matrix content, grain attitude, bounding faces between beds and internal longitudinal/transverse geometry. The couplet-style stratified strata might play an active role in landscape evolution.

关键词： Couplet-style stratification Formative model Sedimentological features Landform

AN EXAMINATION OF LEGAL REGULATIONS FOR INSIdER dEALING IN THE UK ANd THE LESSONS FOR CHINA

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Frontiers of Law in China-Selected Publications from Chinese Universities 2017年第4期12卷 524-560页

作者： ZHENG Weiwei ph.d. School of Law Jilin University of China Changchun China

The UK＇s position as a leading international financial center depends not only on the openness and competitiveness of its market, but also on its reputation as a clean and fair place to do business. Market confidence will be undermined where participants and users believe markets are susceptible to abuse. Thus, the main convincing justification for controlling insider＇s abuse of power is based on the harm principle, which it causes to investor confidence and securities markets. An insider ought not to be able to take advantage of his position either to breach a confidence or to achieve an unfair advantage in the market place; particularly the market place should, as far as possible, provide equality of opportunity to people entering it. Insider dealing has been regulated by the criminal law involved under Part V of the Criminal Justice Act 1993 in the UK. It has become clear that the traditional criminal penalty was limited by the criminal standard of proof required, while self-regulatory regimes are thought as toothless tigers. Although various potential common law civil remedies for breach of fiduciary duty and breach of confidence relating to insider dealing do exist, they are ineffective remedies and beset by so many complexities. As a response, the Financial Services and Markets Act 2000 came into force and marked an important development in the regulation of market abuse in creating civil penalties, which also contained misuse of confidential insider information. Later, the main substantive changes to existing civil market abuse regime have been taken effect within the Financial Services and Markets Act 2000 （Market Abuse） Regulations 2005, 2011 and 2014. Regarding to the regulatory framework, the range of regulatory powers of the Financial Services Authority, which has been replaced by the Financial Conduct Authority in April 1, 2013, available in combating market abuse is one of the most fundamental innovations of the FSMA 2000 and plays a significant role i

关键词： insider dealing criminal prosecution civil penalty regulatory sanction marketabuse

Evaluation of fire smoke control in underground space

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Underground Space 2022年第3期7卷 295-310页

作者： Anastasios Kallianiotis despina Papakonstantinou Ilias CTolias Andreas Benardos Mining Engineer Ph.D.School of Mining&Metallurgical EngineeringNational Technical University of AthensGreece Mineral Resources Engineer Ph.D.CandidateSchool of Mining&Metallurgical EngineeringNational Technical University of AthensGreece Mechanical Engineer Ph.D.National Centre for Scientific Research“Demokritos”Greece Assistant Professor School of Mining and Metallurgical EngineeringTechnical University of AthensGreece

The main goal of the fire management strategy is to avoid people interaction with fire hazards,therefore several studies are carried out for optimal escape route planning as well as smoke management and mechanical ventilation *** spaces are a special case of study due to their technical characteristics that create different fire spread conditions compared to conventional *** this paper,a comparative study on the fire smoke propagation is carried out taking into account the use and performance of smoke mitiga-tion *** Underground Hazardous Waste Management Repository of Lavrion Technological and Cultural Park in Greece,is selected as a case study to achieve the paper objectives.A Computer Fluid dynamic software is used to simulate various fire scenarios based on the specific characteristics of the underground *** that have significant impact on evacuation procedure and human health such as visibility and carbon monoxide concentration are ***,the results are presented and an evaluation method is proposed based on evacuation simulation results,in order to predict the impact of the smoke control design on the conditions inside the underground *** results reveal that the ventilation shaft(passive system)offers an effective smoke control without any other combined control system and that the installation of smoke curtains,which are activated on time,offers significant improvement on smoke spread control extending the available egress time(ASET)in case of fire.

关键词： Fire smoke mitigation Underground space safety Personnel safety

EVOLUTION OF THE BENEFICIAL OWNERSHIP CONCEPT： MORE THAN HALF OF CENTURY OF UNCERTAINTY ANd WHAT HISTORY CAN TELL US

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Frontiers of Law in China-Selected Publications from Chinese Universities 2017年第4期12卷 501-523页

作者： Bruno da Silva ph.d. in International Tax Law Faculty of Law University of Amsterdam Amsterdam

The beneficial ownership concept has constituted for more than half a century one of the most fundamental and debated issues in the application of tax treaties. This article goes back to routes of this term explaining the reason of its original inclusion in the OECd Model Tax Convention and why ultimately such inclusion may have not been necessary. Then it analyses the historical developments of beneficial ownership in the OECd Model Tax Convention. For that purpose it considers different interpretations adopted by jurisdictions （particularly in China） and local courts delving into some of the landmark cases on the subject. Finally it provides a detailed analysis of the current meaning of beneficial ownership considering the most recent developments in the Commentary to the OECd Model Tax Convention.

关键词： beneficial ownership OECd Model Tax Convention Commentary,interpretation case-law China

Assessing the effect of different natural dissolved organic matters on the cytotoxicity of titanium dioxide nanoparticles with bacteria

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Journal of Environmental Sciences 2016年第10期28卷 230-236页

作者： Xiaojia He donee' McAlliser Winfred G. Aker Huey-min Hwang department of Biology Jackson State University Jackson MS 39217 USA Environmental Science ph.d. Program Jackson State University Jackson MS 39217 USA

Titanium dioxide nanoparticles （TiO2 NPs） are among the most widely manufactured nanomaterials on a global scale. However, prudent and vigilant surveillance, incumbent upon the scientific community with the advent of new technologies, has revealed potentially undesirable effects of TiO2 NPs on biological systems and the natural environment during their application and discharge. Such effects are likely best evaluated by first assessing the fate of the TiO2 NPs in natural environments. In this study, the effects of terrestrial humic acid （HA） and tannic acid （TA）, two major members of the collective： dissolved organic matter （dOM）, on the cytotoxicity of TiO2 NPs to Escherichia coli were investigated in the presence and absence of natural sunlight. Qualitative （transmission electron microscopy （TEM）） and quantitative （LCso） analyses were employed in this study. In addition, the production of reactive oxygen species （ROS） in the form of .OH was further assessed-as HA or TA increased the production of ROS decreased. The inhibition of bacterial viability in the light treatment groups, with respective treatment organics at concentrations of 10 ppm, was less in TA than in terrestrial HA. SAS was used to analyze the treatment effect of individual factors of light irradiation, dOM, and concentration of TiO2 NPs.

关键词： TiO2 nanoparticlesHumic acid Tannic acid CytotoxicityROS

diabetes, Exercise and Competitive Sports

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中国运动医学杂志 2006年第3期25卷 355-364页

作者： Peter A. Farrell department of Exercise and Sport ScienceEast Carolina University Greenville NC 27858 Ph.D.

People with diabetes mellitus—rapidly approaching one-third of the US population—either cannot produce insulin (Type 1 dM) or the insulin they produce is ineffective in stimulating the uptake of blood sugar (glucose) into the body’s cells (Type 2 dM). Accordingly, if diabetes is untreated, blood sugar rises to dangerously high levels that can eventually cause blindness, nerve damage, and other complications. Blood sugar can be controlled by the appropriate administration of insulin and other drugs and/or by the manipulation of dietary carbohydrate and exercise.during exercise, the contracting muscles produce their own insulin-like effect,causing the rapid uptake of glucose from the blood. In people without diabetes,the body naturally reduces its production of insulin to compensate; otherwise, blood glucose would fall precipitously. (A low blood glucose concentration is known as hypoglycemia.) Those with Type 1 dM (and those with Type 2 dM who use insulin to control their blood sugar) must adjust their pre-exercise insulin dosage and their carbohydrate intake before, during, and after exercise to avoid becoming hypoglycemic.

关键词：糖尿病运动保健治疗

Numerical simulation of channel pattern changes Part Ⅱ:Application in a conceptual channel

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International Journal of Sediment Research 2010年第4期25卷 380-390页

作者： Hong WANG1, Gang ZHOU2, and Xuejun SHAO31 ph.d., Associate Professor, State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China. 2 Graduate student for a ph.d. degree (at the time of this research work), State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China. Presently: Post-doctoral research fellow, Chinese Research Academy of Environmental Sciences, Beijing 100012, China 3 ph.d., Professor, State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China. [a] ph.d. Associate Professor State Key Laboratory of Hydroscience Engineering Tsinghua University Beijing 100084 China [b] Graduate student for a Ph.D. degree (at the time of this research work) State Key Laboratory of Hydroscience Engineering Tsinghua University Beijing 100084 China. Presently: Post-doctoral research fellow Chinese Research Academy of Environmental Sciences Beijing 100012 China [c] Ph.D. Professor State Key Laboratory of Hydroscience Engineering Tsinghua University Beijing 100084 China

This paper presents simulated channel patterns for various scenarios in a conceptual alluvial valley by an improved two-dimensional (2-d) mathematical model described in the companion paper. Starting from the same initial channel, different channel patterns have been simulated over a real time period of 250 days for varied boundary and initial conditions, including the inlet water discharge and sediment load, initial valley slope, and erodibility of river banks. Impacts of these control factors are discussed, in terms of the longitudinal bottom profiles of simulated fluvial channels, the geometry of channel cross sections, and the water surface profiles in the conceptual river valley. Results suggest that the upper and lower parts of the same channel may have different planforms because the sediment transport conditions of the two parts differ greatly. Simulated causal relationship between control variables and channel patterns agrees qualitatively with known channel pattern theories.

关键词： Channel pattern changes Numerical simulation Resistance to bank erosion Sediment transport Braided channel

dIETARY WATER ANd SOdIUM REQUIREMENTS FOR ACTIVE AdULTS

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中国运动医学杂志 2005年第6期24卷 751-756页

作者： W. Larry Kenney physiology and Kinesiology Pennsylvania State University University Park PA Ph.D. FACSM

KEY POINTSAbstract: The 2004 recommendations on water and sodium intake from the Institute of Medicine (IOM) of the National Academy of Sciences are targeted primarily at sedentary Americans. These guidelines for water and salt intake should not be applied to athletes.  Athletes who follow the IOM recommendations to the letter may actually put themselves at risk for unintended decreases in performance or even untoward health consequences.

关键词：运动医学饮水卫生钠元素微量元素