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Journal of Systematics and Evolution 2009年第6期47卷 605-607页

作者： george W.C.HO Shek Shing mAR Richard m.K.SAUNDERS 812 Fu Yuen HouseChuk Yuen South EstateHong KongChina Ying Wa College Hong KongChina Division of Ecology and Biodiversity School of Biological SciencesThe University of Hong Kong

Populations of Thismia tentaculata(Burmanniaceae tribe Thismieae) are described and illustrated from Tai mo Shan in Hong Kong,southern *** represents the first report of the genus and tribe from continental China.

关键词： Burmanniaceae Hong Kong new record Thismiaceae Thismia tentaculata

Highway bridge seismic design:summary of FHWA/mCEER project on seismic vulnerability of new highway construction

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Earthquake Engineering and Engineering Vibration 2002年第1期1卷 10-19页

作者： Ian m.Friedland Ian G.Buckle george C.Lee Applied Technology Council 1300 Pennsylvania Ave NWSuite 700Washington D.C.20004USA Associate Director for Development Department of Civil Engineering University of Nevada-RenoMail Stop 258RenoNevada89557USA Professor multidisciplinary Center for Earthquake Engineering Research.University at Buffalo.Red Jacket Quadrangle.Buffalo.New York 14260.USA Samuel P.Capen Professor

The Federal Highway Administration (FHWA) sponsored a large,multi-year project conducted by the multidisciplinary Center for Earthquake Engineering Research (mCEER) titled'Seismic Vulnerability of New Highway Construction'(mCEER Project 112),which was completed in *** coordinated the work of many researchers,who performed studies on the seismic design and vulnerability analysis of highway bridges,tunnels,and retaining structures. Extensive research was conducted to provide revisions and improvements to current design and detailing approaches and national design specifications for highway *** program included both analytical and experimental studies,and addressed seismic hazard exposure and ground motion input for the *** system;foundation design and soil behavior: structural importance,analysis,and response:structural design issues and details;and structural design criteria.

关键词： Seismic design specifications bridges seismic hazard exposure ground motion input structural response analysis foundation design soil behavior

Interactions of Aurein with model membranes and Antimalarials

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American Journal of Analytical Chemistry 2024年第2期15卷 72-98页

作者： Anaif m. Alhewaitey Nsoki Phambu Naif m. Alhawiti Department of Chemistry Tennessee State University Nashville USA Department of Chemistry University of Tabuk Tabuk Saudi Arabia CAHFS University of California Davis Davis USA

Aurein is a cationic antimicrobial peptide, rich in phenylalanine residues. Although the peptide has been extensively studied, its mechanism of action is not fully understood and has not been established. This project is focused on studying the interactions of aurein with model biological membranes and antimalarials using Fourier Transform Infrared (FTIR), fluorescence, dynamic light scattering (DLS), atomic force microscopy (AFm), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) techniques. FTIR data revealed conformational changes to the secondary structure of the peptide in the presence of the model membranes. The strongest interactions of aurein were found with DOPC and lipid raft systems. Fluorescence data revealed some differences in the mechanism of interaction between aurein and lipid rafts. Topographical analysis was performed using atomic force microscopy (AFm). AFm images of the peptide with its lipid rafts showed a change in surface roughness suggesting a different mechanism of interaction. DLS data in agreement with FTIR confirmed that aurein interacts differently with the lipid rafts. The results gathered from this study provided new insights on the interaction of aurein. On the other hand, drug-drug interaction issues continue to present a major dilemma for the clinician caring for complex patients such as those infected with infectious disease. This study has examined the interaction of aurein with quinine, primaquine, and chloroquine. Significant interactions between aurein and antimalarials occured at a higher concentration of antimalarials. Interactions between aurein and anti-malarials reveal a strong interaction between aurein and primaquine. Interactions between aurein and quinine or chloroquine were found to be weak and negligible. FTIR, TGA, and DSC may be used in a complementary way to gain insights into the possible drug-drug interactions involving aurein. These studies are needed to initiate in vivo controlled

关键词： Aurein Fluorescence DPPC SPm cholesterol DPPC-SPm-CHOL Quinine Antimalarials

Synthesis and Characterization of Poly Styrene-Co-Poly 2-Hydroxyethylmethacrylate (HEmA) Copolymer and an Investigation of Free-Radical Copolymerization Propagation Kinetics by Solvent Effects

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Open Journal of Polymer Chemistry 2024年第1期14卷 63-93页

作者： Anaif m. Alhewaitey Ishrat Khan Naif m. Alhawiti Department of Chemistry Clark Atlanta University Atlanta USA Department of Chemistry University of Tabuk Tabuk Saudi Arabia CAHFS University of California Davis Davis California

A series of homo and copolymers of styrene (ST) and 2-hydroxyethyl methacrylate (HEmA) in three different media (bulk, tetrahydrofuran, and benzene) have been investigated by free radical polymerization method. The samples obtained from the synthesis were characterized by Fourier Transform-Infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H NmR), atomic force microscopy (AFm), and differential scanning calorimetry (DSC). The results show that the synthesis of the polymers is more feasible under neat conditions rather than solvent directed reaction. moreover, the DSC data shows that the polystyrene obtained is amorphous in nature and therefore displayed only a glass transition signal rather than crystallization and melting peaks. In addition, this study indicates that homolopolymerization of styrene via free radical polymerization tends to be preferable in less polar solvents like THF than in non-polar solvents like benzene. Benzene might destabilize the formation of the reactive radicals leading to the formation of the products. In summary, the homolpolymerization of styrene is more feasible than the homopolymerization 2-hydroxyethyl methacrylate under the experimental setup used. Styrene is more reactive than 2-hydroxyethyl methacrylate than free radical polymerization reaction due in part of the generation of the benzylic radical intermediate which is more stable leading to the formation of products than alkyl radical which are less stable. Furthermore, polymerization of styrene under neat conditions is preferable in solvent-assisted environments. The choice of solvent for the synthesis of these polymers is crucial and therefore the selection of solvent that leads to the formation of a more stable reaction intermediate is more favorable. It is worth noting that the structure of the proposed copolymer consists of a highly polar and hydrophilic monomer, 2-hydroxyethyl methacrylate and a highly non-polar and hydrophobic monome

关键词： 2-Hydroxyethyl methacrylate Polymerization

Edge chipping resistance of ceramics:Problems of test method

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Journal of Advanced Ceramics 2013年第4期2卷 370-377页

作者： george A.GOGOTSI Pisarenko Institute for Problems of Strength 2Timiryazevskaya Str.01014KievUkraine

An unconventional method for determining the fracture resistance of brittle materials is *** method employs a conical indenter to chip the rectangular edge of the *** features of the method are the use of small specimens and the evaluation of the resistance of materials to the nucleation,initiation and propagation of a *** is shown that this method is somewhat similar to the Hertzian fracture method and to the way that early man selected stones to make tools and *** data of the fracture resistance of ceramics is *** is confirmed that if a ceramic material is similar to the model material of linear elastic fracture mechanics(LEFm),then those fracture resistance values are directly proportional to the critical stress intensity factors(baseline).For elastic and inelastic ceramics,R-lines characterizing the fracture resistance to crack growth are *** is shown that proportionality lines(edge chipping resistance versus critical stress intensity factor)may be straight lines for ceramics with similar structure(such as Y-TZP and mg-PSZ).The effect of rounding of the conical indenter tip(10-800μm)on chip scar shape is *** aspects in the fracture behavior of ceramics during edge chipping are also *** advantages and disadvantages of the method are *** studies in this mechanico-physical research area are suggested.

关键词： mechanical characterization micromechanics indentation phase transformation edge fracture(EF)method

Transdermal delivery of 4-aminopyridine accelerates motor functional recovery and improves nerve morphology following sciatic nerve crush injury in mice

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Neural Regeneration Research 2020年第1期15卷 136-144页

作者： Andrew RClark Chia george Hsu m A Hassan Talukder mark Noble John CElfar Center for Orthopaedic Research and Translational Science Penn State Hershey College of MedicineMilton S.Hershey Medical CenterHersheyPAUSA Department of Orthopaedics The University of Rochester Medical CenterRochesterNYUSA Department of medicine Aab Cardiovascular Research InstituteUniversity of Rochester School of Medicine and DentistryRochesterNYUSA Department of Biomedical Genetics The University of Rochester Medical CenterRochesterNYUSA

Oral 4-aminopyridine(4-AP)is clinically used for symptomatic relief in multiple sclerosis and we recently demonstrated that systemic 4-AP had previously unknown clinically-relevant effects after traumatic peripheral nerve injury including the promotion of re-myelination,improvement of nerve conductivity,and acceleration of functional *** hypothesized that,instead of oral or injection administration,transdermal 4-AP(TD-4-AP)could also improve functional recovery after traumatic peripheral nerve *** with surgical traumatic peripheral nerve injury received TD-4AP or vehicle alone and were examined for skin permeability,pharmacokinetics,functional,electrophysiological,and nerve morphological properties.4-AP showed linear pharmacokinetics and the maximum plasma 4-AP concentrations were proportional to TD-4-AP *** a single dose of TD-4-AP administration demonstrated rapid transient improvement in motor function,chronic TD-4-AP treatment significantly improved motor function and nerve conduction and these effects were associated with fewer degenerating axons and thicker myelin sheaths than those from vehicle *** findings provide direct evidence for the potential transdermal applicability of 4-AP and demonstrate that 4-AP delivered through the skin can enhance in-vivo functional recovery and nerve conduction while decreasing axonal *** animal experiments were approved by the University Committee on Animal Research(UCAR)at the University of Rochester(UCAR-2009-019)on march 31,2017.

关键词： 4-aminopyridine electron microscopy functional recovery nerve conduction velocity peripheral nerve injury pharmacokinetics transdermal administration

Achieving higher strength in Cu–Ag–Zr alloy by warm/hot rolling

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Rare metals 2017年第4期36卷 263-267页

作者： S. Chenna Krishna Abhay K. Jha Bhanu Pant Koshy m. george materials and mechanical Entity Vikram Sarabhai Space Centre Trivandrum 695022 India

High-strength Cu-3Ag-0.5Zr alloy plates were produced by multi-pass rolling in the temperature range of 500-800 ℃. An increase in strength was observed by rolling in the aforementioned range without significant loss in ductility. All the rolled samples show higher strength than solution-treated and aged samples. The maximum strength was observed for plates rolled at 500 ℃ with a yield strength and ultimate tensile strength of 311 and 385 mPa, respectively, and retaining a ductility of 23 %. Transmission electron microscopy （TEm） studies showed uniform distribution of fine silver precipitates and high dislocation density in the rolled samples. Nevertheless, the size of precipitates and dislocation density varied with the rolling temperature. The superior strength achieved in the rolled samples is attributed to grain refinement, dislocation strengthening, and precipitation hardening. This method can be employed to produce high-strength plates of pre- cipitation hardenable copper alloys.

关键词： Warm/hot rolling Higher strength Copperalloy Strengthening

The discovery of the fat-regulating phosphatidic acid phosphatase gene

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Frontiers in Biology 2011年第3期6卷 172-176页

作者： george m.CARmAN Department of Food Science and Rutgers Center for Lipid Research Rutgers UniversityNew BrunswickNew Jersey 08901U.S.A.

Phosphatidic acid phosphatase is a fat-regulating enzyme that plays a major role in controlling the balance of phosphatidic acid(substrate)and diacylglycerol(product),which are lipid precursors used for the synthesis of membrane phospholipids and *** acid is also a signaling molecule that triggers phospholipid synthesis gene expression,membrane expansion,secretion,and *** this important enzyme has been known for several decades,its gene was only identified recently from *** discovery showed the importance of phosphatidic acid phosphatase in lipid metabolism in yeast as well as in higher eukaryotes including humans.

关键词： phosphatidic acid phosphatase yeast lipin phospholipid triacylglycerol

Evaluation of co-metabolic removal of trichloroethylene in a biotrickling filter under acidic conditions

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Journal of Environmental Sciences 2017年第7期29卷 54-61页

作者： Dhawal Chheda george A.Sorial Department of Biomedical Chemicaland Environmental EngineeringCollege of Engineering and Applied ScienceUniversity of Cincinnati701 Engineering Research Center2901 Woodside DriveCincinnatiOH 45221-0012USA

This study investigated the removal of hydrophobic trichloroethylene（TCE） in the presence of methanol（co-metabolite） in a biotrickling filter,which was seeded with fungi at pH *** was chosen as the biomass control *** systems,Biofilter I（methanol：TCE 70：30） and Biofilter II（methanol：TCE 80：20） were run in parallel,each with varying composition *** TCE loading rates for both biofilters ranged from 3.22 to 12.88 g/m^3/*** on the ratio,methanol concentrations varied from 4.08 to 27.95 g/m^3/*** performance of the systems was evaluated and compared by calculating removal kinetics,carbon mass balance,efficiencies and elimination *** was observed to enhance TCE removal during the initial loading ***,methanol later inhibited TCE degradation above 6.44 g TCE/m^3/hr（Biofilter I） and 3.22 g TCE/m^3/hr（Biofilter II）.Conversely,TCE did not impede methanol removal because over 95% methanol elimination was consistently ***,Biofilter I was able to outperform Biofilter II due to its greater resistance towards methanol competition.

关键词： Biofiltration Biotrickling Filter Fungi methanol Trichloroethylene

^(60)Co Gamma Irradiation and Annealing Effects on Transport Properties of Antimony Telluride Platelets Grown by Physical Vapor Deposition

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Acta metallurgica Sinica(English Letters) 2015年第5期28卷 559-566页

作者： Thankamma george A.G.Kunjomana Crystal Research Centre Department of Physics Christ University

Physical vapor deposition method was employed to deposit antimony telluride （Sb2Te3） crystals in a dual-zone furnace. The microstructure, surface topography and composition of samples were characterized using X-ray diffraction, atomic force and scanning electron microscopy. Seebeck coefficient （Sic）, electrical conductivity （σ⊥c） as well as power factor （PF） were enhanced for pure Sb2Te3 samples upon annealing, and the samples annealed at 473 K exhibited the highest PF of 3.16 × 10^-3 W m-1K-2 with an enhancement of 22% in the figure of merit （Z）. When the delivered dose of 60Co gamma radiation was increased from 0 to 30 kGy in the stoichiometric crystals, σ⊥c decreased due to the decrease in mobility. As a result of the increase in S, PF and Z improved by 12.11 and 13.7%, respectively, in the 30 kGy gamma- irradiated crystals. Both RH （BIIc） and S⊥c were positive, suggesting that the prepared Sb2Te3 crystals retained the p-type semiconductivity after these treatments.

关键词： Antimony telluride Physical vapor deposition Irradiation Annealing Conductivity Seebeck coefficient