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Particuology 2019年第2期17卷 219-226页

作者： Rayees Ahmad Rather Ramandeep K. Sarwara Niranjan Das Bonamali Pal School of Chemistry and Biochemistry Thapar Institute of Engineering and Technology Patiala 147004 Punjab India Department of Biotechnology Thapar Institute of Engineering and Technology Patiala 147004 Punjab India

This study presents a viable green synthesis approach to produce Ag and Cu nanoparticles (MNPs) by using carbohydrates such as glucose, fructose, sucrose, and starch as reducing agents and describes theirantimicrobial activities against Escherichia coli DH5a. Optical and diffused light scattering analyses showed the Ag NPs ranged from 20 to 75 nm and the Cu NPs varied from 20 to 160 nm, which supports the differences in their absorption bands (400-434 nm for Ag and 458-641 nm for Cu). The reducing sugars interacted differently with Ag^+ and Cu^2+ based on their size and hydrolysis by NaOH resulting in effective stabilization of Ag^0 and Cu^0 and variation in the bactericidal activities of the MNPs. The antibacterial effects of the MNPs were evaluated by measuring the inhibition zones using E. coli DH5a as a test organism. No growth was observed by restreaking different parts of the clearly inhibited zones into new culture plates indicating the bactericidal efficacy of the Ag and Cu MNPs. The Ag NPs were found to be more effective in terms of the size of their in hibition zones (1.21-1.82 cm) compared with those of the Cu NPs (0.0-1.2 cm). This study provides a promising basis for the formulation of a new gen eration of bactericidal agents.

关键词： Green synthesis Ag and Cu nanoparticles Carbohydrate reducing agents Antibacterial activities

Group Multi-Role Assignment With Conflicting Roles and agents

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IEEE/CAA Journal of Automatica Sinica 2020年第6期7卷 1498-1510页

作者： Haibin Zhu IEEE Department of Computer Science and Mathematics Nipissing UniversityNorth BayOntarioP1B 8L7Canada

Group role assignment(GRA)is originally a complex problem in role-based collaboration(RBC).The solution to GRA provides modelling techniques for more complex *** with constraints(GRA+)is categorized as a class of complex assignment *** present,there are few generally efficient solutions to this category of *** special problem case requires a specific *** multi-role assignment(GMRA)and GRA with conflicting agents on roles(GRACAR)are two problem cases in GRA+.The contributions of this paper include:1)The formalization of a new problem of GRA+,called group multi-role assignment with conflicting roles and agents(GMAC),which is an extension to the combination of GMRA and GRACAR;2)A practical solution based on an optimization platform;3)A sufficient condition,used in planning,for solving GMAC problems;and 4)A clear presentation of the benefits in avoiding conflicts when dealing with *** proposed methods are verified by experiments,simulations,proofs and analysis.

关键词： Group Multi-Role Assignment With Conflicting Roles and agents

Assessment of mobile and potential mobile trace elements extractability in calcareous soils using different extracting agents

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Frontiers of Environmental Science & Engineering 2020年第1期14卷 109-125页

作者： Mohsen Jalali Ziba Hurseresht Department of Soil Science College of AgricultureBu_Ali Sina UniversityHamedanIran

Understanding trace elements mobility in soils,extracting agents,and their relationships with soil components,are essential for predicting their movement in soil profile and availability to plants.A laboratory study was conducted to evaluate extractability of cadmium(Cd),cobalt(Co),copper(Cu),nickel(Ni),and zinc(Zn)from calcareous soils utilizing various extracting agents to be specific CaCU,DTPA,EDTA,HNO3,MgCl2,NaN03,NH4NO3,and *** analysis indicated that DTPA and NH4OAc,HN03 and EDTA,and M gCl2 and NH4NO3 extracting agents yielded comparative values,whereas NaN03 and CaCl2 have shown different behavior than other extracting agents for all studied trace *** speciationof extracted trace elements in solutions indicated that in the CaCl2,NaN03,NH4NO3,and MgCl2 extracting agents most extracted Cd,Co,Ni,Zn,and part f Cu were as free ions and may be re-adsorbed on soils,leading to lower extractability,whereas,in the caseof HNO3 extracting agent,the likelihoodof re-adsorptionof trace elements may be *** resultsof speciationof trace elements using NH4OAc DTPA,and EDTA extracting agents showed that Me-(Acetate)3,Me-(Acetate)2(aq),Me(DTPA)3-3-,Me(EDTA)2-.and MeH(EDTA)-complexes dominated in solutions indicating that the extracted trace elements may not be re-adsorbed on soils,leading to higher *** resultsof this study are useful for short and long-term evaluationsof trace elements mobility and further environmental impacts.

关键词： Mobility Calcareous soils Extracting agents Trace elements

Screening of textile finishing agents available on the Chinese market: An important source of per-and polyfluoroalkyl substances to the environmentpolyfluoroalkyl substances to the environment

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Frontiers of Environmental Science & Engineering 2019年第5期13卷 29-38页

作者： Mehvish Mumtaz Yixiang Bao Wenchao Li Lingxiao Kong Jun Huang Gang Yu State Key Joint Laboratory of Environment Simulation and Pollution Control(SKJLESPC) Beijing Key Laboratory for Emerging Organic Contaminants Control(BKLEOC)School of EnvironmentTsinghua UniversityBeijing 100084China CSD IDEA(Beijing)Environment Test&Analysis Co. Ltd.Beijing 100192China

Organofluorinated surfactants are widely employed in textile finishing agents (TFAs) to achieve oil, water, and stain repellency. This has been regarded as an important emission source of per-and polyfluoroalkyl substances (PFASs) to the environment. China is the biggest manufacturer of clothes, and thus TFA production is also a relevant industrial activity. Nevertheless, to date, no survey has been conducted on PFAS contents in commercially available TFAs. In the present study, TFA products were investigated by the Kendrick mass defect method. The quantification results demonstrated a significant presence of perfluorooctane sulfonate (0.37 mg/L) in TFAs manufactured by electrochemical fluorination technology. The products obtained by short-chain PFAS-based telomerization were dominated by perfluorooctanoic acid (mean concentration: 0.29 mg/L), whose values exceeded the limits stated in the European Chemical Agency guidelines (0.025 mg/L). Moreover, the total oxidizable precursor assay indicated high levels of indirectly quantified precursors with long alkyl chains (C7–C9). Together, these results suggest that there is currently a certain of environmental and health risks in China that originates from the utilization of TFAs, and a better manufacturing processes are required to reduce such risks.

关键词： Textile finishing agents Kendrick mass defect Total oxidizable precursor assay

Coverage-optimization based guidance of mobile agents for improved control of distributed parameter systems

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Journal of Systems Engineering and Electronics 2019年第3期30卷 601-612页

作者： ZHUANG Bo CUI Baotong WU Wei JIANG Zhengxian School of Internet of Things Engineering Jiangnan University Wuxi 214122 China Key Laboratory of Advanced Process Control for Light Industry (Ministry of Education) Wuxi 214122 China

The control problem of a class of parabolic distributed parameter systems (DPSs) is investigated by using mobile agents with capabilities of sensing and actuating. The guidance strategies of mobile agents based on coverage optimization methods are proposed to improve the control performance of the system and make the state norm of the system converge to zero faster. The coverage optimization problems are constructed based on the measurement of each agent. By solving the coverage optimization problems, the local optimal moving direction of each agent can be obtained. Then the gradient-based agent motion control laws are established. With the indicator function and the surface delta function, this method is generalized to n-dimensional space, and suitable for any sensing region with piecewise smooth boundaries. The stability and control performance of the system are analyzed. Numerical simulations show the effectiveness of the proposed methods.

关键词： distributed parameter systems (DPSs) mobile agents coverage optimization indicator function

Stable Flocking of Multiple agents Based on Molecular Potential Field and Distributed Receding Horizon Control

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Chinese Physics Letters 2011年第4期28卷 47-50页

作者： ZHANG Yun-Peng DUAN Hai-Bin ZHANG Xiang-Yin State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191 Science and Technology on Aircraft Control Laboratory Beihang UniversityBeijing 100191

A novel distributed control scheme to generate stable flocking motion for a group of agents is *** this control scheme,a molecular potential field model is applied as the potential field function because of its smoothness and unique *** approach of distributed receding horizon control is adopted to drive each agent to find its optimal control input to lower its potential at every *** results show that this proposed control scheme can ensure that all agents eventually converge to a stable flocking formation with a common velocity and the collisions can also be avoided at the same time.

关键词： agents agent scheme

Identification of anti-Gram-negative bacteria agents targeting the interaction between ribosomal proteins L12 and L10

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Acta Pharmaceutica Sinica B 2018年第5期8卷 772-783页

作者： Weiwei Wang Chao Liu Ningyu Zhu Yuan Lin JiANDong Jiang Yanchang Wang Yan Li Shuyi Si Beijing Key Laboratory of Antimicrobial agents Institute of Medicinal Biotechnology Peking Union Medical College and Chinese Academy of Medical Sciences State Key Laboratory of Bioactive Substances and Function of Natural Medicine Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Department of Biomedical Sciences College of Medicine Florida State University

Gram-negative bacteria have become the main pathogens and cause serious clinical problems with increased morbidity and mortality. However, the slow discovery of new antimicrobial agents is unable to meet the need for the treatment of bacterial infections caused by drug-resistant strains. The interaction of L12 and L10 is essential for ribosomal function and protein synthesis. In this study, a yeast two-hybrid system was established to successfully detect the interaction between L12 and L10 proteins from gram-negative bacteria Escherichia coli, which allows us to screen compounds that specifically disrupt this interaction. With this system, we identified two compounds IMB-84 and IMB-87 that block L12-L10 interaction and show bactericidal activity against E. coli. We used glutathione-S-transferase(GST) pull-down and surface plasmon resonance(SPR) assays to demonstrate that these compounds disrupt L12-L10 interaction in vitro and the target of compounds was further confirmed by the overexpression of target proteins. Moreover, protein synthesis and elongation factor G-dependent GTPase activities are inhibited by two compounds. Therefore, we have identified two antibacterial agents that disrupt L12-L10 interaction by using yeast two-hybrid system.

关键词： Yeast two-hybrid Escherichia coli Ribosome L12/L10 Antimicrobial agents

Bridging larger gaps in peripheral nerves using neural prosthetics and physical therapeutic agents

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Neural Regeneration Research 2019年第7期14卷 1109-1115页

作者： Muhammad Sana Ullah Sahar Matthew Barton Geoffrey Douglas Tansley School of Engineering and Built Environment Griffith University Clem Jones Centre for Neurobiology and Stem Cell Therapies Griffith University

Peripheral nerve injuries are relatively common and can be caused by a variety of traumatic events such as motor vehicle *** can lead to long-term disability,pain,and financial burden,and contribute to poor quality of *** this review,we systematically analyze the contemporary literature on peripheral nerve gap management using nerve prostheses in conjunction with physical therapeutic *** use of nerve prostheses to assist nerve regeneration across large gaps(> 30 mm) has revolutionized neural *** materials used for nerve prostheses have been greatly refined,making them suitable for repairing large nerve ***,research on peripheral nerve gap management using nerve prostheses reports inconsistent functional outcomes,especially when prostheses are integrated with physical therapeutic agents,and thus warrants careful *** review explores the effectiveness of nerve prostheses for bridging large nerve gaps and then addresses their use in combination with physical therapeutic agents.

关键词： nerve repair nerve conduits nerve prosthesis physical therapeutic agents electric stimulation nerve gap axonal growth nerve regeneration

Direct anti-HCV agents

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Acta Pharmaceutica Sinica B 2016年第1期6卷 26-31页

作者： Xingquan Zhang Division of Infectious Diseases University of CaliforniaSan Diego School of Medicine

Unlike human immunodeficiency virus(HIV)and hepatitis B virus(HBV),hepatitis C virus(HCV)infection is a curable *** direct antiviral agent(DAA)targets are focused on HCV NS3/4A protein(protease),NS5 B protein(polymerase)and NS5 A *** first generation of DAAs includes boceprevir and telaprevir,which are protease inhibitors and were approved for clinical use *** cure rate for genotype 1 patients increased from 45% to 70% when boceprevir or telaprevir was added to standard PEG-IFN/*** effective and less toxic second generation DAAs supplanted these drugs by *** second generation of DAAs includes sofosbuvir(Sovaldi),simeprevir(Olysio),and fixed combination medicines Harvoni and Viekira *** drugs increase cure rates to over 90%without the need for interferon and effectively treat all HCV *** these drugs the "cure HCV"goal has become a *** remain about drug resistance mutations and the high cost of these *** investigation of new HCV drugs is progressing rapidly;fixed dose combination medicines in phase III clinical trials include Viekirax,asunaprevirtdaclatasvirtbeclabuvir,grazoprevirtelbasvir and others.

关键词： Hepatitis C virus Cure HCV Sustained virologic response Direct antiviral agents NS3/4A protease inhibitor

Nobiletin and its derivatives overcome multidrug resistance(MDR) in cancer:total synthesis and discovery of potent MDR reversal agents

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Acta Pharmaceutica Sinica B 2020年第2期10卷 327-343页

作者： Senling Feng Huifang Zhou Deyan Wu Dechong Zheng Biao Qu Ruiming Liu Chen Zhang Zhe Li Ying Xie Hai-Bin Luo School of Pharmacy State Key Laboratory for Quality Research in Chinese MedicinesMacao University of Science and TechnologyAvenida Wai LongTaipaMacaoChina School of Pharmaceutical Sciences Sun Yat-Sen UniversityGuangzhou 510006China

Our recent studies demonstrated that the natural product nobiletin(NOB)served as a promising multidrug resistance(MDR)reversal agent and improved the effectiveness of cancer chemotherapy in ***,low aqueous solubility and difficulty in total synthesis limited its application as a therapeutic *** tackle these challenges,NOB was synthesized in a high yield by a concise route of six steps and fourteen derivatives were synthesized with remarkable solubility and *** the compounds showed improved sensitivity to paclitaxel(PTX)in P-glycoprotein(P-gp)overexpressing MDR cancer *** them,compound 29 d exhibited water solubility 280-fold higher than NOB.A drug-resistance A549/T xenograft model showed that 29 d,at a dose of 50 mg/kg co-administered with PTX(15 mg/kg),inhibited tumor growth more effective than NOB and remarkably increased PTX concentration in the tumors via P-gp ***,Western blot experiments revealed that 29 d inhibited expression of NRF2,phosphorylated ERK and AKT in MDR cancer cells,thus implying 29 d of multiple mechanisms to reverse MDR in lung cancer.

关键词： Nobiletin Cancer multidrug resistance Mechanism P-gp inhibition Reversal agents Solubility Total synthesis