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Complexation of Both Enantiomers of 2-Phenylpropionic Acid with Cyclodextrin: Determination of Binding Constant, Stoichiometry, Bioavailability and Co-Conformation

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Journal of Encapsulation and Adsorption Sciences 2012年第3期2卷 48-59页

作者： Ali Aboel Dahab norman w. Smith Pharmaceutical Sciences Research Division King’s College London UK

Although enantiomers of 2-phenylpropionic acids (2-PPAs), or profens are important group of nonsteroidal anti-inflammatory drugs (NSAIDs) and have been in clinical use for many years, there is no literature covering its binding interaction in particular with cyclodextrins. NSAIDs are marketed as racemates, chiral discrimination and knowledge of enantiomeric bioavailability is essential. Circular dichroism (CD) spectroscopy is the technique of choice for elucidating chirality and monitoring and characterizing molecular recognition phenomena in solution. Methods em-ploying the fundamentals of the simultaneous measurements of absorbance and CD and a novel efficient titration method have been developed to study the binding of β-Cyclodextrin (β-CyD) and the two enantiomers of 2-PPA as a function of pH. The effect on physicochemical properties and bioavailability was investigated. The binding constant, stoichiometry and pKa for both the free and the bound drugs were determined using a Levenburg-Marquadt non-linear equation. The exact nature of the enantiomer discriminating interactions by cyclodextrins (CyDs) is not well understood. In this work, the interactions and co-conformations of both enantiomers of 2-PPA with β-CyD were explained and es-timated using spectroscopic variations upon complexation. The results indicated a change in the physicochemical prop-erties of 2-PPAs upon complexation and highlighted the enantioselective binding of β-CyD as a function of pH. The charge on the guest molecule and its stereochemistry are of great importance in regulating the stability of the guest/β-CyD complexes;hence the bioavailability of drugs. This work elucidates 2-PPAs/β-CyD binding interactions and highlights the effect of β-CyD on drugs with an effective novel method for binding titration and the potential of the simultaneous measurements of absorbance and CD in future chiral drug interactions studies.

关键词： β-Cyclodextrin Binding Constant Bioavailability 2-Phenylpropionic Acid UV and Circular Dichroism

Improving Behavior of Computer Game Bots Using Fictitious Play

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International Journal of Automation and computing 2012年第2期9卷 122-134页

作者： Ushma Kesha Patel Purvag Patel Henry Hexmoor norman Carver Department of Computer Science Southern Illinois University

In modern computer games, ＂bots＂ - intelligent realistic agents play a prominent role in the popularity of a game in the market. Typically, bots are modeled using finite-state machine and then programmed via simple conditional statements which are hard-coded in bots logic. Since these bots have become quite predictable to an experienced games＇ player, a player might lose interest in the game. we propose the use of a game theoretic based learning rule called fictitious play for improving behavior of these computer game bots which will make them less predictable and hence, more a enjoyable game.

关键词： Agents computer game bots fictitious play game theory learning Nash equilibrium.

Light Hydrocarbons in Fluid Inclusions and Their Constraints on Ore Genesis:A Case Study of the Songxi Ag(Sb)Deposit,Eastern Guangdong,China

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Acta Geologica Sinica(English Edition) 2003年第2期77卷 227-236页

作者： SUNKai wANGMin CHENBinghui CHENJingde YUShoujun SUNXiaoming DavidI.norman DepartmentofEarthSciences SunYat-senUniversityGuangzhouGuangdong510275China StateKeyLaboratoryforMineralDepositsResearch NanjingUniversityNanjingJiangsu210093China DepartmentofEarthandEnvironmentalSciences NewMexicoInstituteofMiningandTechnology(NMT)SocorroNM87801USA

The Songxi deposit is a newly discovered large Ag (Sb) deposit. By using a suite of high-vacuum quadrupole gas mass spectrometer systems, the authors have recognized many kinds of light hydrocarbons in fluid inclusions of minerals. These hydrocarbons are mainly composed of C1-C4 saturated alkanes, while the contents of C2-C4 unsaturated alkenes and aromatic hydrocarbons are quite low, suggesting that the metallogenic processes have not been affected by magmatic activities. Chemical equilibrium studies show that these hydrocarbons may be a mixture of organic gases generated by microorganism activity and those by thermal cracking of type-n kerogens (kukersite) in sedimentary host rocks, and the former may constitute more than two-thirds, implying that microorganism might have played an important role in the metallogenesis. The equilibrium temperature of the latter is about 300℃, which is much higher than the geothermal temperature at the estimated depth of metallogenesis. Thus, the light hydrocarbons generated by thermal cracking of kerogens probably originated in the deep part of the sedimentary basins and then migrated through a long distance to shallower horizons of the basin. Based on the composition of light hydrocarbons in fluid inclusions, the authors infer that the Songxi deposit was formed in a continental rift. The analytical data presented in this paper support from one aspect the genetic model that the Songxi deposit may be a sedimentary hot brine transformed deposit instead of a submarine basic volcanic exhalation and low-medium temperature volcanic hydrothermal fluid filling deposit proposed by most previous researchers.

关键词： light hydrocarbons fluid inclusion Ag (Sb) deposit Songxi Guangdong China

Characteristics of CO_2 sequestration in saline aquifers

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Petroleum Science 2010年第1期7卷 83-92页

作者： Yang Fang Bai Baojun Tang Dazhen Shari Dunn-norman David wronkiewicz School of Energy Resources China University of Geosciences Beijing 100083 China Department of Geological Sciences and Engineering Missouri University of Science and Technology Rolla MO 65401USA

Storage of CO2 in saline aquifers is a viable option for reducing the amount of CO2 released to the atmosphere. This paper provides an overall review of CO2 sequestration in saline aquifers. First, the principles of CO2 sequestration are presented, including CO2 phase behavior, CO2-water-rock interaction, and CO2 trapping mechanisms. Then storage capacity and CO2 injectivity are discussed as the main determinants of the storage potential of saline aquifers. Next, a site section process is addressed considering basin characteristics, reservoir characteristics, and economic and social concerns. Three main procedures are then presented to investigate the suitability of a site for CO2 sequestration, including site screening, detailed site characterization, and pilot field-scale test. The methods for these procedures are also presented, such as traditional site characterization methods, laboratory experiments, and numerical simulation. Finally, some operational aspects of sequestration are discussed, including well type, injection rate, CO2 purity, and injection strategy.

关键词： CO2 sequestration saline aquifer site selection screening criteria geological storage storage capacity

Light hydrocarbon in ore-forming fluids and its constraints on ore genesis——A case study on Changkeng large-scale Au-Ag deposit, central Guangdong, China

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Chinese Science Bulletin 1999年第S2期44卷 58-61页

作者： D. l. norman Department of Earth & Environmental Sciences New Mexico Institute of Mining & Technology (NMT) Socorro NM87801 USA

ORGANIC matters in the ore-forming fluids are composed mainly of light hydrocarbons. Because of the small amount of hydrocarbons in fluid inclusions, it is quite difficult to study their behavior in mineralizing processes, excepting methane （CH4）. In this work, we used a high vacuum quadrupole gas massspectrometer system to determine the content and composition of light hydrocarbons (C1-7) in fluid inclusions in minerals collected from Changkeng Au-Ag deposit. The geological significance of the new data forgenesis of the deposit has been discussed briefly.

关键词： light hydrocarbons ore-forming fluid ore genesis Changkeng Au-Ag deposit.

Regulation of cancer stem cells in triple negative breast cancer

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Cancer Drug Resistance 2021年第2期4卷 321-342页

作者： norman Fultang Madhuparna Chakraborty Bela Peethambaran Department of Pathology and Laboratory Medicine University of PennsylvaniaPhiladelphiaPA 19140USA Department of Biological Sciences The University of the SciencesPhiladelphiaPA 19140USA.

Triple Negative Breast Cancer(TNBC)is the most lethal subtype of breast *** the successes of emerging targeted therapies,relapse,recurrence,and therapy failure rates in TNBC significantly outpace other subtypes of breast *** evidence suggests accumulation of therapy resistant Cancer Stem Cell(CSC)populations within TNBCs contributes to poor clinical *** CSCs are enriched in TNBC compared to non-TNBC breast *** mechanisms underlying CSC accumulation have been well-characterized and discussed in other *** this review,we focus on TNBC-specific mechanisms that allow the expansion and activity of self-renewing *** highlight cellular signaling pathways and transcription factors,specifically enriched in TNBC over non-TNBC breast cancer,contributing to *** also analyze publicly available single-cell RNA-seq data from basal breast cancer tumors to highlight the potential of emerging bioinformatic approaches in identifying novel drivers of stemness in TNBC and other cancers.

关键词： Cancer stem cells TNBC transcriptional regulation breast cancer

A Framework for Assessing Import Costs of Medical Supplies and Results for a Tuberculosis Program in Karakalpakstan,Uzbekistan

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Health Data Science 2021年第1期2021卷 120-132页

作者： Stefan Kohler norman Sitali Nicolas Paul Heidelberg Institute of Global Health Faculty of Medicine and University HospitalHeidelberg UniversityHeidelbergGermany Médecins Sans Frontières BerlinGermany Institute of Social Medicine Epidemiology and Health EconomicsCharité–Universitätsmedizin Berlincorporate member of Freie Universität Berlin and Humboldt-Universität zu BerlinBerlinGermany

*** of medical supplies is common,but limited knowledge about import costs and their structure introduces uncertainty to budget planning,cost management,and cost-effectiveness analysis of health *** aimed to estimate the import costs of a tuberculosis(TB)program in Uzbekistan,including the import costs of specific imported *** developed a framework that applies costing and cost accounting to import ***,transport costs,customs-related costs,cargo weight,unit weights,and quantities ordered were gathered for a major shipment of medical supplies from the Médecins Sans Frontières(MSF)Procurement Unit in Amsterdam,the Netherlands,to a TB program in Karakalpakstan,Uzbekistan,in ***,air freight,land freight,and customs clearance cost totals were ***,total import costs were allocated to different cargos(standard,cool,and frozen),items(e.g.,TB drugs),and units(e.g.,one tablet)based on imported weight and *** sources were order invoices,waybills,the local MSF logistics department,and an MSF standard product *** shipment contained 1.8 million units of 85 medical items of standard,cool,and frozen *** average import cost for the TB program was 9.0%of the shipment *** cost varied substantially between cargos(8.9–28%of the cargo value)and items(interquartile range 4.5–35%of the item value).The largest portion of the total import cost was caused by transport(82–99%of the cargo import cost)and allocated based on imported ***(14%)of the 69 items imported as standard cargo were associated with 85%of the standard cargo import *** cargo items could be grouped based on contributing to import costs predominantly through unit weight(e.g.,fluids),imported quantity(e.g.,tablets),or the combination of unit weight and imported quantity(e.g.,items in powder form).*** cost of importing medical supplies to a TB program in Karakalpakstan,Uzbekistan,was sizable,variable,an

关键词： imported items cargo

Transmission Capacity Analysis for Linear VANET under Physical Model

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China Communications 2017年第3期14卷 97-107页

作者： Xinxin He Hang Zhang weisen Shi Tao Luo norman C.Beaulieu Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing 100876 China

In this study, the transmission capacity of VANETs in a highway scenario is analysed on the basis of a 1D line model and the carrier sense multiple access with collision avoidance(CSMA/CA) protocol. we describe the CSMA/CA protocol used in IEEE802.11 p from the perspective of the geometric relationship amongst simultaneous transmitters. The desired channel and interfering channels are assumed to experience the same amount of path-loss and Rayleigh fading. On the basis of the proposed model, we analyse the attempted transmission probability of each road segment and the maximum intensity of active transmitters, including their theoretical values. Then, we employ the physical model to obtain the outage probability and derive the upper bound of the transmission capacity of a VANET, which is defined as the average spatial density of successful transmissions in the network. Simulation results indicate that the theoretical value offers a good bound on network capacity.

关键词： VANET transmission capacity line model CSMA/CA

Clean energy:A common goal for humanity Preface to the inaugural issue of Clean Energy

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Clean Energy 2017年第1期1卷 1-2页

作者： Dr wen Ling norman N.Li 不详

Clean Energy-a new high-end academic journal-is launch-ing with this *** journal will include significant discoveries,as well as the latest developments and engineering practices relat-ing to the global energy science,technology,and engineer-ing *** is the basic material needed to guarantee the survival of *** countries give significant import-ance to energy technology and have formulated relevant energy policies and technical development strategies based on their resource endowment and technical and economic development levels.

关键词： Clean journal guarantee