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A DNA delivery system containing listeriolys in Oresults in enhanced hepatocytedirected gene expression

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World Journal of Gastroenterology 1999年第6期5卷 465-469页

作者： Cherie m. Walton, Catherine H. Wu and George Y. Wu Department of medicine Division of Gastroenterology-Hepatology University of Connecticut Health Center Farmington CT United States Department of medicine Division of Gastroenterology-Hepatology University of Connecticut Health Center Farmington CT 06030 United States

AIm To determine whether incorporation of the pH dependent bacterial toxin listeriolysin O (LLO) into the DNA carrier system could increase the endosomal escape of internalized DNA and result gene expression. mETHODS A multi component delivery system was prepared consisting of asialoglycoprotein (ASG), poly L lysine (PL), and LLO. Two marker genes, luciferase and β galactosidase in plasmids were complexed and administered in vitro to Huh7[ASG receptor (+) ] and SK Hep1[ASG receptor (-) ] cells. Purity, hemolytic activity, gene expression, specificity, and toxicity were evaluated. RESULTS An LLO containing conjugate retained cell targeting specificity and membranolytic activity. In ASG receptor (+) cells, luciferase gene expression was enhanced by more than 7 fold over that of conjugates without the incorporation of listeriolysin O. No significant expression occurred in ASG receptor (-) cells. Enhancement of β galactosidase gene expression was less, but still significantly increased over controls. There was no detectable toxicity at concentrations shown to be effective in transfection studies. CONCLUSIONS ASOR PL can be coupled to LLO using disulfide bonds, and successfully target and increase the gene expression of foreign DNA.

关键词： DNA gene expression listeriolysin O hepatocytes

Synthesis and photoswitching properties of azobenzene liquid crystals with a pentafluorobenzene terminal

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Chinese Chemical Letters 2014年第12期25卷 1611-1614页

作者： md Lutfor Rahman Gurumuthy Hegde Shaheen m.Sarkar mashitah mohd Yusoff Faculty of Industrial Sciences  Technology Universiti Malaysia PahangKuantan 26300Malaysia

The fluorine-substituted benzoate ester rod-shaped liquid crystals containing an azobenzene side chain linked with terminal double bonds were synthesized and *** mesophase and photoswitching properties were determined by polarizing optical microscopy（POm）,differential scanning calorimetry（DSC） and UV-visible *** rod-shaped compound 4a having an odd number of carbon atoms in the alkyl chains exhibits nematic phase and SmA type phase whereas compound 4b having an even number of carbon atoms showed only nematic *** fluorinecontaining compounds 4c and 4d showed only SmA type *** photoswitching properties of these compounds showed a rate of trans to cis isomerization ranging 19-20 s,whereas reverse process took around 230 min in *** materials may be ideal in the field of optically rewritable applications where both on and off rates should be crucial.

关键词： Liquid crystals Azobenzene Photoswitching Fluorine compounds

Hydrogen Bonding in Hydrogenated Amorphous Germanium

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Tsinghua Science and Technology 2004年第2期9卷 177-180页

作者： m. S. Abo-Ghazala S. Al Hazmy Physics Department Faculty of Science Menoufia University Sheben El-Koom EgyptChemistry Department Faculty of Science Sana University Yemen

Thin films of hydrogenated amorphous germanium (a-Ge:H) were prepared by radio frequency glow discharge deposition at various substrate temperatures. The hydrogen distribution and bonding struc-ture in a-Ge:H were discussed based on infrared absorption data. The correlation between infrared absorp-tion spectra and hydrogen effusion measurements was used to determine the proportionality constant for each vibration mode of the Ge-H bonds. The results reveal that the bending mode appearing at 835 cm1 is associated with the Ge-H2 (dihydride) groups on the internal surfaces of voids. While 1880 cm1 is assigned to vibrations of Ge-H (monohydride) groups in the bulk, the 2000 cm1 stretching mode is attributed to Ge-H and Ge-H2 bonds located on the surfaces of voids. For films associated with bending modes in the infrared spectra, the proportionality constant values of the stretching modes near 1880 and 2000 cm1 are found to be lower than those of films which had no corresponding bending modes.

关键词： hydrogenated amorphous germanium hydrogen bonding film

Climate change effects on rangelands and rangeland management:affirming the need for monitoring

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Ecosystem Health and Sustainability 2017年第3期3卷 1-14页

作者： Daniel W.mcCollum John A.Tanaka Jack A.morgan John E.mitchell William E.Fox Kristie A.maczko Lori Hidinger Clifford S.Duke Urs P.Kreuter Rocky mountain Research Station USDAForest Service240 W.Prospect RoadFort CollinsColorado 80526 USA James C.Hageman Sustainable Agriculture Research and Extension Center University of WyomingDept 33541000 E.University AvenueLaramieWyoming 82071 USA USDA ARS Rangelands Resources Research Unit8408 Hildreth RoadCheyenneWyoming 82009 USA Texas A&m AgriLife Research Ecosystem Science&Management720 E.Blackland RoadTempleTexas 76502 USA Consortium for Science Policyand OutcomesArizona State UniversityPO Box 875603TempeArizona 85287 USA Ecological Society of America 1990 M StreetNWSuite 700WashingtonD.C.20036 USA Ecosystem Science and management Texas A&M University2138 TAMUCollege StationTexas 77843 USA

Uncertainty as to the extent and magnitude of changes in conditions that might occur due to climate change poses a problem for land and resource managers as they seek to adapt to changes and mitigate effects of climate *** illustrate using scenarios of projected future conditions on rangelands in the Northern Great Plains and Desert Southwest of the United *** two regions are different in the ways climate change is projected to affect the *** of a longer and warmer growing season in the Northern Great Plains could lead to increased forage production and land *** uncertain effects on summer monsoons that primarily control rangeland productivity in the Desert Southwest,combined with the possibility of more intense and/or frequent drought events,could present land managers with challenges stemming from decreased forage production and land *** projections,though uncertain,provide land managers with basic insight into future conditions they might *** need more.A focus on vulnerability and resilience,with explicit recognition of interactions between ecological and socio-economic factors,coupled with systematic monitoring and assessment of observable conditions on the land to supplement information based on climate projections,will more effectively provide critical and specific information managers need to adaptively manage rangelands under uncertain climate futures.

关键词： adaptive management climate change indicators monitoring rangelands resilience uncertainty vulnerability

Stress Corrosion Crack Growth Behavior of Titanium Alloy/Bioactive Glasses Sandwiches in Simulated Human Physiological Environment

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Journal of materials Science & Technology 2002年第5期18卷 387-391页

作者： DaCHEN J.m.mcNaney E.Saiz A.P.Tomsia R.O.Ritchie Dept. of mat. Sci. Shanghai Jiaotong Univ. Shanghai 200030 China Dept. of mat. Sci. and Eng. Univ. of California Berkeley CA 94720 United States mat. Sci. Div. Lawrence Berkeley Natl. Lab. Berkeley CA 94720 United States

Based on a series of newly developed bioactive glasses having suitable thermo-mechanical properties to allow application as fixation agents between bone and titanium alloy biomedical implants, the stress corrosion crack growth (SCCG) behavior of their interfaces with Ti6AI4V was investigated in simulated body fluid (SBF) with the objective of discerning the salient mechanisms of crack advance and to assess the reliability of the bonds. Results indicated that crack growth rates in Ti6AI4V/glass/Ti6AI4V sandwich specimens were nearly the same as or slightly lower than those in the bulk glasses at comparable stress intensities; indeed, cracks would prefer to propagate off the interface, suggesting that the Ti6AI4V/glass interface has relatively good crack-growth resistance. mechanistically, interfacial crack growth appears to be controlled by the classic stress corrosion mechanisms for silicate glasses, with no discernible effect of bioactivity on the SCCG behavior being observed.

关键词： Stress corrosion Titanium alloy Bioactive glass Crack growth

A New Occurrence of （Gold-Bearing） Graphite in the Assosa Region, BenishanguI-Gumuz State, W Ethiopia

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Journal of Earth Science and Engineering 2015年第7期5卷 417-435页

作者： Liam A. Bullock Owen J. morgan School of Geoscienees University of Aberdeen Aberdeen AB24 3UE United Kingdom Tactical Environmental Response Yorkshire LS29 9BZ United Kingdom

Polyurethanes from Kraft Lignin without Using Isocyanates

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Journal of Renewable materials 2018年第4期6卷 413-425页

作者： F.J.Santiago-medina m.C.Basso A.Pizzi L.Delmotte LERmAB University of Lorraine27 rue Philippe Seguin88000 EpinalFrance Department of Physics King Abdulaziz UniversityJeddahSaudi Arabia material Science Institute of mulhouse UMR CNRS 7361University of Upper Alsace15 rue Jean StarckyBP 248868057 Mulhouse CedexFrance

The reaction of a desulphurized kraft lignin with hexamethylene diamine and dimethyl carbonate has allowed the development of isocyanate-free polyurethane *** present research work is based on previous studies made with hydrolyzable and condensed tannins,but takes advantage of the higher number of hydroxyl groups present in lignin and their different aliphatic and aromatic *** obtained materials were analyzed by Fourier transform infrared(FTIR)spectroscopy,matrix-assisted laser desorption ionization time-of-flight(mALDI-TOF)mass spectrometry and solid-state cross-polarization/magic angle spinning(CP mAS)13C nuclear magnetic resonance(NmR),which have revealed the presence of urethane *** interpretation of the results has shown a larger number of species than when tannins were used and has indicated the presence of two types of bonds in the new molecules formed:ionic and covalent bonds.

关键词： Lignin urethanes non-isocyanate polyurethanes mALDI-TOF FTIR

Syntheses,Crystal Structures and Luminescent Properties of Lead(Ⅱ) and Cadmium(Ⅱ) Coordination Polymers Constructed from Biphenyl-2,5,3′-tricarboxylate

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Chinese Journal of Structural Chemistry 2014年第6期33卷 888-896页

作者：高竹青李红晋 m.Kirillov Alexander 顾金忠 School of Chemical and Biological Engineering Taiyuan University of Science and Technology Centro de Química Estrutural Complexo I Instituto Superior TécnicoThe University of Lisbon College of Chemistry and Chemical Engineering Lanzhou University

Two coordination polymers, namely [Pb（Hbtc）（phen）]n（1） and {[Cd3（btc）2（H2O）4]·2H2O}n（2, H3btc = biphenyl-2,5,3＇-tricarboxylic acid, phen = 1,10-phenanthroline）, were assembled. Single-crystal X-ray diffraction studies show that compound 1 possesses a zigzag chain 1D coordination network, which is further extended into a 3D supramolecular architecture via O–H···O hydrogen bonds and π-π packing interactions. Compound 2 features a 3D open framework based on a tricadmium（II） subunit, generating a trinodal 4,4,6-connected net with the 4,4,6T24 topology defined by the point symbol of（44·62）3（46·69）2. Thermal stability and luminescent properties of both compounds were studied and discussed.

关键词： coordination polymer crystal structrue luminescent properties

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冷冻喷丸修边的功能及其不足

橡胶参考资料 1999年第9期29卷 38-38页

作者： Stacy m.morgan 杨钧

冷冻高速喷丸修边是橡胶工业中采用的一种将飞边从橡胶模压制品上去掉的工艺。该工艺采用各种组合的液氮,高速旋转和介质(喷丸)将飞边去掉,是一种高精度,经济和有效的方法(见图1)。

关键词：冷冻喷丸修边橡胶制品修边模压制品