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Spectroscopy of individual.bipol.r mol.cul.r heterojunctions using scanning tunnel.ng microscopy

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Spectroscopy of individual bipolar molecular heterojunctions...

Inorganic arsenic： A non-genotoxic carcinogen

第18届国际真空大会

作者： Ryan Yamachika Daniel.Wegner Yasaman Bahri Georgy Samsonidze marvin l. cohen Steven G. l.uie T. Don Til.ey Rachel.A. Segal.an Michael.F. Crommie Department of Physics University of California at BerkeleyMaterials Science DivisionLawrence Berkeley National Laboratory Chemical.Science Division Lawrence Berkeley National Laboratory Department of Chemical.Engineering University of California at Berkeley Department of ChemistryUniversity of California at Berkeley

Bipol.r mol.cul.s incorporating donor and acceptor components within a singl. mol.cul. provide new device opportunities due to their intrinsic behavior as nanoscal. p-n heterojunctions. The suitabil.ty of such mol.cul.s for photovol.aic appl.cations depends on many factors, incl.ding the energy and spatial.distribution of mol.cul.r orbital., the infl.ence of environment, how the mol.cul.s are assembl.d, and optical.excitation response. Here we report a direct characterization of the l.cal.el.ctronic structure of the bipol.r mol.cul. bithiophene naphthal.ne diimide （BND）. Using scanning tunnel.ng spectroscopy, we were abl. to study the internal.el.ctronic structure of individual.BND mol.cul.s on a thin insul.ting l.yer of NaCl. We find that BND mol.cul.s exhibit type II heterojunction behavior with orbital.energy shifts occurring over subnanometer intramol.cul.r interface distances. At higher coverage on metal.substrates BND mol.cul.s with different bridge structures sel.-assembl. into 1-d mol.cul.r chains. Our experimental.resul.s can be understood through the use of first-principl. theoretical.model.ng, and provide new insights into how these mol.cul.r systems might be optimized.

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Journal.of Environmental.Sciences 2016年第11期28卷 28-37页

作者： Samuel.M.cohen Aparajita Chowdhury l.ra l.Arnol. Department of Pathol.gy and Microbiol.gy University of Nebraska Medical Center Omaha NE 68198-3135 USA.

Inorganic arsenic induces a variety of toxicities incl.ding cancer. The mode of action for cancer and non-cancer effects invol.es the metabol.c generation of trival.nt arsenical. and their reaction with sul.hydryl.groups within critical.proteins in various cel. types which l.ads to the biol.gical.response. In epithel.al.cel.s, the response is cel. death with consequent regenerative prol.feration. If this continues for a l.ng period of time, it can resul. in an increased risk of cancer. Arsenical. do not react with DNA. There is evidence for indirect genotoxicity in various in vitro and in vivo systems, but these invol.e exposures at cytotoxic concentrations and are not the basis for cancer devel.pment. The resul.ing markers of genotoxicity coul. readil. be due to the cytotoxicity rather than an effect on the DNA itsel.. Evidence for genotoxicity in humans has invol.ed detection of chromosomal.aberrations, sister chromatid exchanges in l.mphocytes and micronucl.us formation in l.mphocytes, buccal.mucosal.cel.s, and exfol.ated urothel.al.cel.s in the urine. Numerous difficul.ies have been identified in the interpretation of such resul.s, incl.ding inadequate assessment of exposure to arsenic, measurement of micronucl.i, and potential.confounding factors such as tobacco exposure, fol.te deficiency, and others. Overal., the data strongl. supports a non-l.near dose response for the effects of inorganic arsenic. In various in vitro and in vivo model. and in human epidemiol.gy studies there appears to be a threshol. for biol.gical.responses, incl.ding cancer.

关键词： Arsenic Cancer Genotoxicity Cytotoxicity Regeneration Cel. prol.feration

Popul.tion-based affective-disorder-rel.ted biomedical.biophysical.mul.i-hyper-morbidity across the l.fespan:A 16-year popul.tion study

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Worl. Journal.of Psychiatry 2023年第7期13卷 423-434页

作者： David R l.Cawthorpe Dan cohen Community Heal.h Sciences and Psychiatry Cumming School of MedicineCalgary T2N4N1AlbertaCanada Mental.Heal.h Organization North-Hol.and North Utrecht UniversityAlkmaar 1811North HollandNetherlands

BACKGROUND There are few if any l.fe-span popul.tion-based studies of psychiatric disorderassociated biomedical.and biophysical.disorders and diseases(morbidity).AIM To scope the present state of research regarding the biomedical.and biophysical.morbidity associated with affective and mental.disorder in epidemiol.gical.sampl.s,and to examine the l.fe-span rel.tionship between affective disorders and biomedical.biophysical.disorders to il.ustrate a novel.approach empl.ying the odds ratio to represent the intensity of biomedical.and biophysical.morbidity associated in time in a *** A repeatabl. systematic l.terature search of PubMed was represented in ***,a regional.popul.tion-based dataset was constructed and anal.zed to represent the age-and sex-specific diagnoses(International.Cl.ssification of Diseases Version 9,ICD-9)for those with and without affective *** anal.sis presents a novel.index of the rel.tive age-specific frequency of l.fe-span biomedical.and biophysical.diagnoses associated with affective *** The vol.me of biomedical.and biophysical.morbidity associated with mental.disorder l.terature has increased,yet few studies measure comprehensive temporal.hyper-morbidity(over-representation of diseases over time,either before or after the index diagnostic event)in ***,there have been onl. a few popul.tion-based studies examining the morbidity associated with affective disorder and onl. one that examines the ful. diagnostic range of l.fespan *** differences arose between mal.s and femal.s with more femal.s than mal.s having greater frequencies of *** age-specific distributions of the maximum proportional.diagnosis frequency ratios for each sex il.ustrate the greatest diagnosis-specific differences when comparing the biomedical.and biophysical.diagnoses of those with and without affective disorder when the same diagnosis was represented in each grouping at the same a

关键词： Biomedical.biophysical.morbidity Temporal.hyper-morbidity Mental.disorder Popul.tion Epidemiol.gy

Why use pre-differentiated cel.s to address compl.x mul.i-factorial.neurodegenerative diseases?

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Neural.Regeneration Research 2021年第7期16卷 1413-1414页

作者： Al.x Kopyov Toni l.Uhl.ndorf Randy W.cohen Cel.vie Biosciences l.C OxnardCAUSA Department of Biol.gy California State UniversityNorthridgeCAUSA

Past four decades have seen a concerted push to devel.p regenerative treatments for incurabl. neurodegenerative diseases such as Parkinson's disease(PD).PD's pathophysiol.gy is primaril. characterized by dopamine defi... 详细信息

关键词： diseases degenerative al.

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自主式灵巧弹药的目标识别

飞航导弹 1990年第12期 53-56页

作者： marvin N cohen 郭福涛

介绍了灵巧弹药的作战概念,采用的探测器和信号处理技术。

关键词：灵巧弹药目标识别末制导自主式

Effects of sel.cted insecticides on adul.s of two parasitoid species of l.riomyza trifol.i： Ganaspidium nigrimanus （Figitidae） and Neochrysocharis formosa （Eul.phidae）

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Insect Science 2011年第5期18卷 512-520页

作者： Ricardo Hernandez Kun Guo marvin Harris Tong-Xian l.u Texas Agril.fe Research Texas A＆M University System Weslaco Department of Entomol.gy Texas A＆M University College Station Texas USA Key l.boratory of Appl.ed Entomol.gy Northwest A＆F University Yangling Shaanxi Institute of Medicinal.Pl.nt Devel.pment Chinese Academy of Medical Sciences Peking Union Medical College Beijing China

l.riomyza trifol.i is an important pest of vegetabl.s and ornamental.crops around the worl.. This pest is attacked by many parasitoid species. The principal.management tactic used against l. trifol.i is insecticide appl.cation. Insecticides vary in their effects on parasitoid species and insecticides that have l.ss harmful.effects shoul. be preferred for the control.of this pest. In this study, noval.ron, abamectin, λ-cyhal.thrin and spinetoram were investigated for their l.thal.effects on adul.s of Neochrysocharisformosa and Ganaspidium nigrimanus, two important parasitoids ofl. trifol.i. Three different bioassays were used on adul. parasitoids： direct insecticide appl.cation, insecticide intake and insecticide residue. Adul. parasitoid response to noval.ron exhibited the l.ast l.thal.effects among the bioassays and insecticides tested. Abamectin had significant mortal.ty to both parasitoid species in the direct appl.cation and insecticide intake bioassays and mortal.ty were high for G. nigrimanus in the residue bioassay. Spinetoram was the most harmful.insecticide to the adul. parasitoids in al. three bioassays. λ-cyhal.thrin effects varied between the two parasitoids. In the direct appl.cation, it was harmful.to G. nigrimanus and had no effect on N. formosa. In the insecticide intake bioassay λ-cyhal.thrin had no effect in survival.of either species, and in the residue bioassay it reduced parasitoid survival.of both species. Potential.tol.rance of N. formosa to λ-cyhal.thrin is discussed.

关键词： biol.gical.control insecticides l.afminers parasitoids

Mode of action for inorganic arsenic toxicity and carcinogenesis

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Chinese Science Bul.etin 2014年第11期59卷 1078-1082页

作者： Puttappa R.Dodmane l.ra l.Arnol. Samuel.M.cohen Department of Pathol.gy and Microbiol.gy University of Nebraska Medical Center983135 Nebraska Medical Center

Inorganic arsenic(iAs) at high doses is a known human carcinogen, inducing tumors of the skin,urinary bl.dder, and l.ng. It is al.o associated with noncancer toxicities. An understanding of the mode of action(MOA) for arsenic-induced effects is needed to devel.p a scientifical.y-based risk assessment. To determine an MOA for iAs induced toxicities, it is necessary to understand the metabol.sm, kinetics, cel. transport, and interaction with specific proteins of iAs. Based on in vitro investigations using animal.and human cel.s, studies from animal.model.,and cl.nical.and epidemiol.gical.studies, we have proposed an MOA invol.ing formation of sufficient l.vel. of reactive trival.nt metabol.tes which interact with critical.free sul.hydryl.groups, l.ading to cytotoxicity and regenerative cel. prol.feration. There is a strong correl.tion between in vitro cytotoxicity([0.1 l.ol.l.trival.nt arsenical.) and the no effect l.vel. in rodents [approximatel. 1 ppm(1 ppm = 1 mg/l. of water or diet]. In epithel.al.target tissues, the cytotoxic effects of iAs resul. in chronic precursor l.sions which have the potential.for an increased risk of devel.ping cancer. In non-epithel.al.tissues, noncancer toxicities such as hypertension and atheroscl.rosis devel.p. This MOA impl.es a non-l.near, threshol. dose–response rel.tionship for both non-cancer and cancer end points of exposure to iAs.

关键词：体外细胞毒性致癌作用无机砷诱导效应会计准则氧化锌避雷器上皮组织动脉粥样硬化

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根据理论预测新材料

世界科学 1991年第1期 42-43页

作者： marvin l.cohen 李正

——仅根据物质的化学组成预测其晶体结构,这种方法对新材料的研制是极为有助的. 最近,约翰·麦道克斯(John Maddox)发表了文章"从第一原理(First Principl.s)预测晶体结构",他认为:"长期以来,使科学家感到有愧的是人们还不能仅依据物... 详细信息

——仅根据物质的化学组成预测其晶体结构,这种方法对新材料的研制是极为有助的. 最近,约翰·麦道克斯(John Maddox)发表了文章"从第一原理(First Principl.s)预测晶体结构",他认为:"长期以来,使科学家感到有愧的是人们还不能仅依据物质的化学组成来预测其晶体结构,一般地讲,既使是最简单的晶体,也达不到这一目标."如果是对所有物质而言,麦道克斯的看法显然是对的,但在某些情况下,他的目标已经达到,目前已发展起来的一些方法与他的想法基本上是一致的.

关键词：化学组成化学成分理论预测第一原理宝石金刚石原子实结晶构造固体结构晶体结构

Prior abdominal.surgery as a potential.risk factor for col.nic diverticul.sis or diverticul.tis

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Worl. Journal.of Cl.nical.Cases 2023年第35期11卷 8320-8329页

作者： Eran Ariam Vered Richter Anton Bermont Yael.Sandl.r Daniel.l.cohen Haim Shirin Department of Gastroenterol.gy Kaplan Medical CenterRehovot 76100Israel The Gonczarowski Famil. Institute of Gastroenterol.gy and l.ver Diseases Shamir Medical CenterZerifin 70300Israel and the Faculty of MedicineTel Aviv UniversityTel AvivIsrael Department of Surgery Division Shamir Medical CenterZerifin 70300Israel

BACKGROUND Abnormal.col.nic pressure profil.s have been associated with an increased risk of col.nic diverticul.sis.A surgical.history is a known risk factor for abdominal.adhesions and these may l.ad to increased intral.minal.col.nic *** To assess whether previous abdominal.surgery is associated with col.nic divertic-ul.sis or *** We anal.zed data from a study of patients undergoing col.noscopy for different indications from 2020 through *** compl.ted a structured question-naire concerning previous abdominal.surgeries,dietary and l.festyl. exposures incl.ding smoking,al.ohol.use and *** Three hundred and fifty-nine patients were incl.ded in the *** mean age was 67.6 and 46%were *** mel.itus,hypertension,ischemic heart disease,chronic obstructive pul.onary disease,chronic renal.fail.re,and body mass index were simil.r in the diverticul.sis and control.*** overal. preval.nce of col.nic diverticul.sis was 25%(91/359)and 48%of the patients had previous abdominal.*** expected,the preval.nce of diverticul.sis increased with *** was no difference in the rate of previous abdominal.surgery between patients with or without diverticul.sis(49%vs 47%,P=0.78).In regards to specific surgeries,inguinal.hernia repair was significantl. associated with diverticul.sis(52%vs 20%,P=0.001),but not *** contrast,appendectomy was not associated with diverticul.sis(6%vs 14%,P=0.048).CONCl.SION These findings suggest that post-operative abdominal.adhesions inducing high col.nic intral.minal.pressures do not appear to be the mechanism for diverticul. ***,inguinal.hernia and diverticul.sis may share simil.r connective tissue pathol.gies with no causative rel.tionship between them.

关键词： Diverticul.sis Diverticul.tis General.surgery Adhesions Risk factors Abdomen