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Demonstration of Covalent Sidewall Functionalization of Single Wall Carbon Nanotubes by NMR Spectroscopy:Side Chain Length Dependence on the Observation of the Sidewall sp^(3)Carbons

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Nano Research 2008年第1期1卷 72-88页

作者： Liling Zeng Lawrence B.Alemany Christopher L.Edwards andrew R.Barron richard E.Smalley Institute for Nanoscale Science and Technology and Department of Chemistry Rice UniversityHoustonTX 77005USA

Carboxylic acid-functionalized single walled carbon nanotubes(SWNTs)prepared via the reaction of an amino acid,NH2(CH2)nCO2H where n=1(glycine,GLY),5(6-aminohexanoic acid,AHA),10(11-aminoundecanoic acid,AUDA),with fl uorinated single walled carbon nanotubes(F-SWNTs)have been characterized by MAS 13C NMR *** ease of observing the aliphatic CH2 groups and the resolution of the signal are dependent on the length of the amino acid’s aliphatic *** have proposed that where substituent chains are short(making NMR data collection difficult)chemical modification to extend the chain length should alleviate analysis *** this regard,we have investigated the esterifi cation of the carboxylic acid *** amino acid-functionalized SWNTs were esterified with an appropriate alcohol to ensure parity of the overall substituent length,i.e.,GLY-SWNT(C1)+1-dodecanol(C_(12))=DOD-GLY-SWNT(1),AHA-SWNT(C_(5))+1-octanol(C_(8))=OCT-AHA-SWNT(2),and AUDA-SWNT(C_(10))+1-propanol(C_(3))=PRO-AUDA-SWNT(3).The 13C NMR shift for the sp3 nitrogen-substituted carbon atoms of the SWNT sidewall is observed atδ≈75 *** the length of SWNT sidewall functional groups enhances the ability to observe the sidewall sp^(3)*** methylene carbon signal intensity is less attenuated in the dipolar dephasing spectrum of the ester-functionalized SWNTs than their associated amino acid derivatives,suggesting more motional freedom of the side chain in the solid *** confi rmation of the dipolar dephasing spectral effects was assisted by the characterization of the ester of AUDA-SWNT with 1,3-propanediol:PPD-AUDA-SWNT(4).

关键词： Single walled carbon nanotube(SWNT) nuclear magnetic resonance(NMR) esterification amino acid functionalization

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Vasectomy by epithelial curettage without suture or cautery： a pilot study in humans

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Asian Journal of Andrology 2010年第3期12卷 315-321,I0008页

作者： John K. Amory John W. Jessen Charles Muller richard E. Berger Department of Medicine Center for Research in Reproduction and Contraception University of Washington School of Medicine Seattle WA 98195 USA private Practice Dentistry Seattle WA 98195 USA Department of Urology University of Washington School of Medicine Seattle WA 98195 USA

Curettage of the epithelium of the vas deferens might be a safe and effective method of male sterilization. We conducted a pilot study of vasectomy by epithelial curettage with a novel microcurette called the Vas-X in 12 normal men requesting elective sterilization. Seminal fluid analysis was obtained monthly after the procedure for 6 months. Pain was assessed by questionnaire. Three months after the procedure, all men attained sperm concentrations of less than 0.2 million sperm per mL, and seven were azoospermic. Post-procedural pain was minimal. Nine men ultimately achieved and maintained azoospermia; however, 4 to 6 months after the procedure, sperm concentrations increased in three of the 12 subjects, necessitating repeat vasectomy. Microscopic examination of the vas deferens from these failures revealed re-canalization. Vasectomy by epithelial curettage can result in effective sterilization; however, 1/4 of the subjects were not effectively sterilized by the procedure due to re-canalization of the vas deferens. Epithelial curettage will require further refinement to determine if it is a viable form of vasectomy.

关键词： male contraception male sterilization re-canalization spermatogenesis vas deferens vasectomy failure

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Impact of palliative therapies in metastatic esophageal cancer patients not receiving chemotherapy

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World Journal of Gastrointestinal Surgery 2020年第9期12卷 377-389页

作者： Sungjin Kim Timothy P DiPeri Michelle Guan Veronica R Placencio-Hickok Haesoo Kim Jar-Yee Liu andrew Hendifar Samuel J Klempner Ryan Nipp Alexandra Gangi Miguel Burch Kevin Waters May Cho Joseph Chao Katelyn Atkins Mitchell Kamrava richard Tuli Jun Gong Biostatistics and Bioinformatics Research Center Samuel Oschin Comprehensive Cancer InstituteCedars-Sinai Medical CenterLos AngelesCA 90048United States Division of Surgical Oncology Department of SurgerySamuel Oschin Comprehensive Cancer InstituteCedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Medicine Division of Hematology and OncologySamuel Oschin Comprehensive Cancer InstituteCedars Sinai Medical CenterLos AngelesCA 90048United States Department of Medicine Massachusetts General Hospital Cancer CenterHarvard Medical SchoolBostonMA 02114United States Department of Pathology and Laboratory Medicine Cedars-Sinai Medical CenterLos AngelesCA 90048United States Division of Hematology and Oncology Department of MedicineUniversity of CaliforniaDavisSacramentoCA 95817United States Department of Medical Oncology and Therapeutics Research City of Hope Comprehensive Cancer CenterDuarteCA 91010United States Department of Radiation Oncology Cedars Sinai Medical CenterLos AngelesCA 90048United States Department of Radiation Oncology Memorial Sloan Kettering Cancer CenterNew YorkNY 10065United States

BACKGROUND Palliative therapy has been associated with improved overall survival(OS)in several tumor *** all patients with metastatic esophageal cancer receive palliative chemotherapy,and the roles of other palliative therapies in these patients are *** To investigate the impact of other palliative therapies in patients with metastatic esophageal cancer not receiving *** The National Cancer Database was used to identify patients between *** with M1 disease who declined chemotherapy and had known palliative therapy status[palliative therapies were defined as surgery,radiotherapy(RT),pain management,or any combination thereof]were *** with unknown chemotherapy,RT,or nonprimary surgery status were ***-Meier estimates of OS were *** proportional hazards regression models were employed to examine factors influencing *** Among 140234 esophageal cancer cases,we identified 1493 patients who did not receive chemotherapy and had complete *** age was 70 years,most(66.3%)had a Charlson Comorbidity Index(CCI)of 0,and 37.1%were treated at an academic *** majority(72.7%)did not receive other palliative *** both univariate and multivariable analyses,there was no difference in OS between those receiving other palliative therapy(median 2.83 mo,95%CI:2.53-3.12)vs no palliative therapy(2.37 no,95%CI:2.2-2.56;multivariable P=0.290).On univariate,but not multivariable analysis,treatment at an academic center was predictive of improved OS[Hazard ratio(HR)0.90,95%CI:0.80-1.00;P=0.047].On multivariable analysis,female sex(HR 0.81,95%CI:0.71-0.92)and non-black,other race compared to white race(HR 0.72,95%CI:0.56-0.93)were associated with reduced mortality,while South geographic region relative to West region(HR 1.23,95%CI:1.04-1.46)and CCI of 1 relative to CCI of 0(HR 1.17,95%CI:1.03-1.32)were associated with increased *** histologic grade and T-stage were also as

关键词： Esophageal cancer Metastatic Palliative Chemotherapy Radiotherapy Survival

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Differential regulation of the anthocyanin profile in purple kiwifruit(Actinidia species)

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Horticulture Research 2019年第1期6卷 1746-1761页

作者： Yongyan Peng Kui Lin-Wang Janine M.Cooney Tianchi Wang richard V.Espley andrew C.Allan School of Biological Sciences University of AucklandAucklandNew Zealand The New Zealand Institute for Plant and Food Research Limited Mt AlbertAucklandNew Zealand The New Zealand Institute for Plant and Food Research Limited East Street3214 HamiltonNew Zealand

Anthocyanins are a group of secondary metabolites that colour fruit and flowers orange,red,purple or blue depending on a number of factors,such as the basic structure,co-pigmentation,metal ion complexation and vacuolar *** biosynthesis of anthocyanin is regulated at the transcriptional level by a group of transcription factors,the MYB–bHLH–WD40(MBW)*** this study,the purple colouration in several kiwifruit(Actinidia)species was identified and characterised as red cyanidin-based and blue delphinidin-based *** differential pigmentation in the skin and flesh can be attributed to the differential ratio of cyanidin and delphinidin derivatives accumulated in the total anthocyanin *** expression of anthocyanin biosynthetic genes chalcone synthase(CHS),flavonoid 3-O-glucosyltransferase(F3GT),flavonoid 3′-hydroxylase(F3′H)and flavonoid 3′5′-hydroxylase(F3′5′H)is crucial for anthocyanin ***,the balance of expression of the F3′H and F3′5′H genes appears responsible for the ratio of cyanidin and delphinidin derivatives,while a lack of CHS,F3GT and MYB110 expression is responsible for a lack of total *** transcriptional regulation of the F3′H and F3′5′H promoters by the R2R3 MYB transcription factor MYB110 is markedly different in tobacco transient *** kiwifruit MYB10 or MYB110 are over-expressed in Actinidia chinensis both cyanidin-based and delphinidin-based anthocyanins are elevated,but F3′H and F3′5′H genes are not strongly correlated with MYB *** results suggest that the core kiwifruit anthocyanin pathway genes are dependent on characterised MYB transcription factors,while other regulatory proteins are more directly responsible for the expression of the F3′H and F3′5′H genes.

关键词： Actinidia orange flowers

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First Nationwide Survey on the Resistance to First Line Anti-Tuberculosis Drugs in Ghana

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Journal of Tuberculosis Research 2018年第1期6卷 68-80页

作者： kennedy K. Addo richard Owusu Christian Bonsu Kwaku Owusu-Darko Samuel O. Addo Gloria I. Mensah Mercy J. Newman David Ofori-Adjei Frank A. Bonsu Department of Bacteriology Noguchi Memorial Institute for Medical Research University of Ghana Accra Ghana Department of Microbiology School of Biomedical and Allied Health Sciences University of Ghana Accra Ghana National Tuberculosis Control Programme Accra Ghana

Background/objective: A nationwide survey on the resistance to first line anti-tuberculosis (anti-TB) drugs was conducted in Ghana from 2007-2008 by Noguchi Memorial Institute for Medical Research in collaboration with the National Tuberculosis Control Programme. We aimed to characterize mycobacterial species causing pulmonary tuberculosis (PTB) and determine the resistance pattern to first line anti-TB drugs among newly diagnosed and previously treated PTB patients in Ghana. Methods: Two sputum samples from consented new smear positive PTB patients who had never been treated for TB or had been on anti-TB treatment for less than a month and patients who had been treated for TB previously for more than a month in selected diagnostic centres nationwide were collected for culture, identification and drug susceptibility test. Culture positive isolates were tested against streptomycin (S), isoniazid (H), rifampicin (R) and ethambutol (E) using the simplified proportion method and line probe assay (LPA). The LPA was performed in mid-2017. Results: Among 410 samples, 345 positive cultures were obtained and identified as Mycobacterium tuberculosis complex (MTBC). Of the 345 isolates, 133 were further differentiated by GenoType MTBC®as M. tuberculosis, 126 (94.7%) and M. africanum 7 (5.3%). The overall drug resistance patterns were as follows: 43/345 (12.5%), 6/345 (1.7%), 9/345 (2.6%) and 71/345 (20.6%) were resistant to H, R, E and S respectively and 5/345 (1.4%) were multi-drug resistant (MDR). Conclusion: The results indicate high levels of resistance to S and H among new and previously treated TB patients. We recommend adequate surveillance systems including periodic national anti-TB drug resistance surveys.

关键词： Tuberculosis National Survey Drug Resistance Ghana

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Radical Addition of Perfluorinated Alkyl Iodides to Multi- Layered Graphene and Single-Walled Carbon Nanotubes

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Nano Research 2010年第2期3卷 138-145页

作者： Christopher E.Hamilton Jay R.Lomeda Zhengzong Sun James M.Tour andrew R.Barron richard E.Smalley Institute for Nanoscale Science and Technology Department of Chemistry and Department of Mechanical Engineering and Materials ScienceRice UniversityHoustonTexas 77005USA

A simple one-pot reaction that serves to functionalize graphite nanosheets(graphene)and single-walled carbon nanotubes(SWNTs)with perfluorinated alkyl groups is *** radical addition of 1-iodo-1H,1H,2H,2H-perfluorododecane to ortho-dichlorobenzene suspensions of the carbon nanomaterial is initiated by thermal decomposition of benzoyl ***,UV photolysis of 1-iodo-perfluorodecane serves to functionalize the carbon ***-SWNTs,perfluorododecyl-graphene,and perfluorodecyl-graphene are characterized by infrared(IR)and Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),thermogravimetric analysis(TGA),and atomic force microscopy(AFM).The products show enhanced dispersability in CHCl3 as compared to unfunctionalized starting *** advantage of this one-pot functionalization procedure lies in the use of pristine graphite as starting material thereby avoiding the use of harsh oxidizing conditions.

关键词： Nanotube single-walled carbon nanotube graphene radical addition

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I AM ART A Close-Up on JR’s global art project

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城市漫步（上海版、英文） 2014年第6期 52-53页

作者： andrew CHIN 不详

When JR won the 2011 TED Prize,he was granted one wish to inspire the *** recipients like Bono and Jamie kennedy used the USD100,000 prize and accompanying attention to kickstart their One Foundation and Food Revolution *** French artist used the platform to start the global art project Inside *** years later,over 15,000 people in 108 countries have participated,including thousands in Shanghai as the project reaches the Mainland.

关键词： global granted Mainland

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Profiles of HIV-Affected Households in Ghana

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Health 2014年第15期6卷 2004-2013页

作者： Amos Laar Daniel Fiaveh Matilda Laar Sandra Boatemaa James Abugri Angela El-Adas richard Amenyah Kyeremeh Atuahene andrew Anthony Adjei Isabella Quakyi Centre for Gender Studies and Advocacy University of Ghana Accra Ghana Department of Applied Chemistry and Biochemistry Faculty of Applied Sciences University for Development Studies Navrongo Campus Tamale Ghana Department of Biological Environmental and Occupational Sciences School of Public Health University of Ghana Accra Department of Pathology Korle-Bu Teaching Hospital College of Health Sciences University of Ghana Accra Ghana Department of Population Family & Reproductive Health School of Public Health University of Ghana Accra Ghana Ghana AIDS Commission Accra Ghana Regional Institute for Population Studies University of Ghana Accra Ghana School of Dietetics and Human Nutrition McGill University Montreal Canada

Background: To contribute to a fuller appreciation of Ghana’s HIV epidemic, this paper presents various profiles of the Ghanaian HIV-affected household. To comprehensively tackle the HIV epidemic in Ghana, the profiles would provide stakeholders with ready information for policy formulation. Methods: We used data from a nationally representative survey that measured livelihood activities, household asset wealth, household composition, health, and nutrition variables of 1745 HIV-affected households. From these emerged various profiles. Results: About 50% of the households are headed by females. Households headed by men have an average size of three members, compared to two for female-headed households. There are far more AIDS widows than widowers. The annual death rate among the surveyed households was about 1000 per 100,000-households. Relatively more deaths occurred in male-headed households. Two-thirds of the households were asset poor. Various coping strategies were instituted by the households in reaction to threat of food insecurity. The national prevalence of chronic energy deficiency is 16%. Conclusions: Our data show that age of household head, hosting of a chronically ill member, and average size of household differed by sex of household head. The annual death rate of 1000 per 100,000 households is very high.

关键词： HIV-Affected Households Profiles HIV Ghana

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Current Status and Future Challenges of Weather Radar Polarimetry: Bridging the Gap between Radar Meteorology/Hydrology/Engineering and Numerical Weather Prediction

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Advances in Atmospheric Sciences 2019年第6期36卷 571-588页

作者： Guifu ZHANG Vivek N.MAHALE Bryan J.PUTNAM Youcun QI Qing CAO andrew D.BYRD Petar BUKOVCIC Dusan S.ZRNIC Jidong GAO Ming XUE Youngsun JUNG Heather D.REEVES Pamela L.HEINSELMAN AlexANDer RYZHKOV Robert D.PALMER Pengfei ZHANG Mark WEBER Greg M.MCFARQUHAR Berrien MOORE III Yan ZHANG Jian ZHANG J.VIVEKANANDAN Yasser AL-RASHID richard L.ICE Daniel S.BERKOWITZ Chong-chi TONG Caleb FULTON richard J.DOVIAK University of Oklahoma NOAA/National Weather Service Enterprise Electronics Corporation NOAA/National Severe Storms Laboratory National Center for Atmospheric Research Raytheon Company Radar Operations Center

After decades of research and development, the WSR-88 D(NEXRAD) network in the United States was upgraded with dual-polarization capability, providing polarimetric radar data(PRD) that have the potential to improve weather observations,quantification, forecasting, and warnings. The weather radar networks in China and other countries are also being upgraded with dual-polarization capability. Now, with radar polarimetry technology having matured, and PRD available both nationally and globally, it is important to understand the current status and future challenges and opportunities. The potential impact of PRD has been limited by their oftentimes subjective and empirical use. More importantly, the community has not begun to regularly derive from PRD the state parameters, such as water mixing ratios and number concentrations, used in numerical weather prediction(NWP) *** this review, we summarize the current status of weather radar polarimetry, discuss the issues and limitations of PRD usage, and explore potential approaches to more efficiently use PRD for quantitative precipitation estimation and forecasting based on statistical retrieval with physical constraints where prior information is used and observation error is included. This approach aligns the observation-based retrievals favored by the radar meteorology community with the model-based analysis of the NWP community. We also examine the challenges and opportunities of polarimetric phased array radar research and development for future weather observation.

关键词： weather radar polarimetry radar meteorology numerical weather prediction data assimilation microphysics parameterization forward operator

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Host-Pathogen Wars: New Weapons from Biotechnology and Genomics

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American Journal of Plant Sciences 2019年第3期10卷 402-416页

作者： Mychele B. da Silva richard F. Davis andrew H. Paterson Nelson Dias Suassuna Shavannor M. Smith Peng W. Chee Department of Plant Pathology University of Georgia Tifton GA USA Institute of Plant Breeding Genetics and Genomics University of Georgia Tifton GA USA Crop Protection and Management Research Unit USDA-ARS Tifton GA USA Plant Genome Mapping Lab University of Georgia Athens GA USA EMBRAPA Algodao Campina Grande Brazil

Pathogens are imminent threats to crop production. Among the management tools available to protect crops from diseases, the use of host-plant resistance had been hindered by a lack of tools and resources to identify resistance genes (R-genes). Genomic technologies have empowered acquisition of a new level and quality of information on plant-pathogen interactions. Next generation sequencing, differential transcriptome analysis, gene editing, and use of bioinformatics have greatly expanded the numbers of R-genes identified, enriched understanding of R-avirulence gene interactions, and disease diagnosis. In this review, we highlight the application of genomic technologies to identification of pathogen machinery for future improvement of host plant resistance.

关键词： Host-Plant Resistance R-Genes Genomics Crop Improvement

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