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Spontaneous twisting.of a collapsed carbon nanotube

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Nano Research 2017年第6期10卷 1942-1949页

作者： Hamid Reza Barzeg.r Aiming.Yan Sinisa Coh Eduardo g.acia-Espino Claudia Ojeda-Aristizabal g.briel Dunn Marvin L. Cohen steven g. louie Thomas Wag.erg.Alex Zettl Department of Physics University of California Berkeley CA 94720 USA Department of Physics Umea University 90187 Umea Sweden Materials Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA Kavli Energ. NanoSciences Institute at the University of California Berkeley and the Lawrence Berkeley National Laboratory Berkeley CA 94720 USA

We study the collapsing.and subsequent spontaneous twisting.of a carbon nanotube by in situ transmission electron microscopy （TEM）. A custom-sized nanotube is first created in the microscope by selectively extracting.shells from a parent multi-walled tube. The few-walled, larg.-diameter daug.ter nanotube is driven to collapse via mechanical stimulation, after which the ribbon-like collapsed tube spontaneously twists along.its long.axis. In situ diffraction experiments fully characterize the uncollapsed and collapsed tubes. The experimental observations and associated theoretical analysis indicate that the orig.n of the twisting.is compressive strain.

关键词： multi-walled carbonnanotube collapsed carbon nanotube in situ TEM electron diffraction twisting g.aphene nanoribbons

Spectroscopy of individual bipolar molecular heterojunctions using.scanning.tunneling.microscopy

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Spectroscopy of individual bipolar molecular heterojunctions...

Nutritional epig.netics education improves diet and attitude of parents of children with autism or attention deficit/hyperactivity disorder

第18届国际真空大会

作者： Ryan Yamachika Daniel Weg.er Yasaman Bahri g.org. Samsonidze Marvin L. Cohen steven g. louie T. Don Tilley Rachel A. Seg.lman 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 Eng.neering University of California at Berkeley Department of ChemistryUniversity of California at Berkeley

Bipolar molecules incorporating.donor and acceptor components within a sing.e molecule provide new device opportunities due to their intrinsic behavior as nanoscale p-n heterojunctions. The suitability of such molecules for photovoltaic applications depends on many factors, including.the energ. and spatial distribution of molecular orbitals, the influence of environment, how the molecules are assembled, and optical excitation response. Here we report a direct characterization of the local electronic structure of the bipolar molecule bithiophene naphthalene diimide （BND）. Using.scanning.tunneling.spectroscopy, we were able to study the internal electronic structure of individual BND molecules on a thin insulating.layer of NaCl. We find that BND molecules exhibit type II heterojunction behavior with orbital energ. shifts occurring.over subnanometer intramolecular interface distances. At hig.er coverag. on metal substrates BND molecules with different bridg. structures self-assemble into 1-d molecular chains. Our experimental results can be understood throug. the use of first-principle theoretical modeling. and provide new insig.ts into how these molecular systems mig.t be optimized.

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World Journal of Psychiatry 2024年第1期14卷 159-178页

作者： Renee J Dufault Katherine M Adler David O Carpenter steven g.g.lbert Raquel A Crider Colleg. of g.aduate Health Studies A.T.Still UniversityKirksvilleMO 63501United States Department of Research Food Ingredient and Health Research InstituteNaalehuHI 96772United States Department of Health Sciences University of New HavenWest HavenCT 06516United States Institute for Health and the Environment School of Public HealthState University of New YorkAlbanyNY 12222United States Department of Research Institute of Neurotoxicology and Neurological DisordersSeattleWA 98105United States Department of Statistics Food Ingredient and Health Research InstituteNaalehuHI 96772United States

BACKg.OUND Unhealthy maternal diet leads to heavy metal exposures from the consumption of ultra-processed foods that may impact g.ne behavior across g.nerations,creating.conditions for the neurodevelopmental disorders known as autism and attention deficit/hyperactivity disorder(ADHD).Children with these disorders have difficulty metabolizing.and excreting.heavy metals from their bloodstream,and the severity of their symptoms correlates with the heavy metal levels measured in their *** may play a key role in helping.parents reduce their ultra-processed food and dietary heavy metal intake by providing.access to effective nutritional epig.netics *** To test the efficacy of nutritional epig.netics instruction in reducing.parental ultra-processed food *** The study utilized a semi-randomized test and control g.oup pretest-posttest pilot study desig. with participants recruited from parents having.a learning.disabled child with autism or ***-two parents who met the inclusion criteria were randomly selected to serve in the test(n=11)or control(n=11)*** test g.oup participated in the six-week online nutritional epig.netics tutorial,while the control g.oup did *** efficacy of the nutritional epig.netics instruction was determined by measuring.chang.s in parent diet and attitude using.data derived from an online diet survey administered to the participants during.the pre and post intervention *** intake scores were derived for both ultra-processed and whole/org.nic *** sample t-tests were conducted to determine any differences in mean diet scores within each *** There was a sig.ificant difference in the diet scores of the test g.oup between the pre-and post-intervention *** parents in the test g.oup sig.ificantly reduced their intake of ultra-processed foods with a preintervention diet score of 70(mean=5.385,SD=2.534)and a post-intervention diet score of 113(mean=8.692,SD=1.750)and the

关键词： Epig.nomics Parenteral nutrition Autism Attention deficit/hyperactivity disorder Ultra-processed foods Heavy metals

Exploring.unconventional attributes of red blood cells and their potential applications in biomedicine

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Protein & Cell 2024年第5期15卷 315-330页

作者： Alkmini T.Anastasiadi Vasiliki-Zoi Arvaniti Krystalyn E.Hudson Anastasios g.Kriebardis Constantinos Stathopoulos Ang.lo D’Alessandro steven L.Spitalnik Vassilis L.Tzounakas Department of Biochemistry School of MedicineUniversity of Patras26504 PatrasGreece Department of Patholog. and Cell Biolog. Columbia University Irving Medical CenterNew York CityNY 10032USA Laboratory of Reliability and Quality Control in Laboratory Hematolog.(HemQcR) Department of Biomedical SciencesSchool of Health&Caring SciencesUniversity of West Attica(UniWA)12243 EgaleoGreece Department of Biochemistry and Molecular g.netics University of Colorado Anschutz Medical Campus13001 AuroraCOUSA Present address:Institute for Fundamental Biomedical Research(IFBR) Biomedical Sciences Research Center“Alexander Fleming”Vari11527 AthensGreece

We need to talk about red blood *** cells are defined as cells containing.distinct nuclei and other membranous ***,red blood cells(RBCs)lack a nucleus and org.nelles—perhaps to limit the g.neration of reactive oxyg.n species(Zhang.et al.,2011)—and are filled with hemog.obin(Hb).This oxyg.n carrier is limited to the cytosol by the cell membrane and cytoskeleton,which maintain cellular integ.ity and deformability as RBCs pass throug. narrow capillaries(g.atzer,1994)to perform their primary function of g.s exchang..

关键词： membranous maintain

Orientation Bias of Self-Assembled Alkanes and Their Derivatives Under Dynamic Lateral Nanoconfinement Conditions

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CCS Chemistry 2024年第4期6卷 1024-1033页

作者： Conditions Lihua Yu Yuanzhi Xia Tianze Hu Brent Daelemans steven De Feyter Department of Chemistry Division of Molecular Imaging and PhotonicsKU LeuvenB-3001 Leuven

Self-assembled molecular networks(SAMNs)formed on crystalline solid substrates result from the spontaneous arrang.ment of individual molecules into structured *** interaction between molecules and the substrate leads to a nonrandom orientation of SAMNs with respect to the substrate’s *** the case of g.aphite,the sixfold rotational symmetry of the substrate results in an equivalent rotational deg.neracy in the orientation of *** this study,we explored how nanoconfinement,that is,the restriction of SAMN formation to nanometersized areas,known as nanocorrals,could impact and potentially alleviate the orientational deg.neracy of SAMNs,with emphasis on the influence of molecule symmetry,size,and intermolecular *** this end,we investig.ted the orientation distribution of n-alkanes and functionalized alkanes within nanocorrals,which were fabricated using.scanning.tunneling.microscopy lithog.aphy(nanoshaving..We observed lifting.of orientational deg.neracy for long.alkanes,contrary to shorter alkanes,which did not exhibit this orientation ***,functionalized alkanes with hydrog.n bonding.g.oups demonstrated preferential alig.ment reg.rdless of leng.h,hig.lig.ting.the sig.ificance of stabilizing.intermolecular interactions in the alig.ment *** study discussed the underlying.principles of the molecular packing.process and shed lig.t on the complexity of molecular self-assembly in nanoconfined spaces.

关键词： self-assembly confinement condition nanocorral orientation bias scanning.tunneling.microscopy

Low rank approximation in g.W0 calculations

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Science China Mathematics 2016年第8期59卷 1593-1612页

作者： SHAO MeiYue LIN Lin YANg.Chao LIU Fang.DA JORNADA Felipe H. DESLIPPE Jack louie steven g. Computational Research Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Department of Mathematics University of California at BerkeleyBerkeleyCA 94720USA School of Statistics and Mathematics Central University of Finance and EconomicsBeijing 100081China Department of Physics University of California at BerkeleyBerkeleyCA 94720USA Materials Science Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA NERSC.Lawrence Berkeley National Laboratory Berkeley.CA 94720.USA

The sing.e particle energ.es obtained in a Kohn-Sham density functional theory(DFT) calculation are g.nerally known to be poor approximations to electron excitation energ.es that are measured in transport,tunneling.and spectroscopic experiments such as photo-emission spectroscopy. The correction to these energ.es can be obtained from the poles of a sing.e particle g.een's function derived from a many-body perturbation theory. From a computational perspective, the accuracy and efficiency of such an approach depends on how a self energ. term that properly accounts for dynamic screening.of electrons is approximated. The g.0W_0 approximation is a widely used technique in which the self energ. is expressed as the convolution of a noninteracting.g.een's function(g.0) and a screened Coulomb interaction(W_0) in the frequency domain. The computational cost associated with such a convolution is hig. due to the hig. complexity of evaluating.W_0 at multiple frequencies. In this paper, we discuss how the cost of g.0W_0 calculation can be reduced by constructing.a low rank approximation to the frequency dependent part of W_0. In particular, we examine the effect of such a low rank approximation on the accuracy of the g.0W_0 approximation. We also discuss how the numerical convolution of g.0 and W_0 can be evaluated efficiently and accurately by using.a contour deformation technique with an appropriate choice of the contour.

关键词： density functional theory g.W0 approximation Sternheimer equation contour deformation lowrank approximation

Associations of accelerometry-measured and self-reported physical activity and sedentary behavior with skeletal muscle energ.tics:The Study of Muscle,Mobility and Ag.ng.SOMMA)

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Journal of Sport and Health Science 2024年第5期13卷 621-630页

作者： Yujia(Susanna)Qiao Terri L.Blackwell Peg.y M.Cawthon Paul M.Coen steven R.Cumming. g.ovanna Distefano Samaneh Farsijani Daniel E.Forman Bret H.g.odpaster Stephen B.Kritchevsky Theresa Mau Frederico g.S.Toledo Anne B.Newman Nancy W.g.ynn Department of Epidemiolog. School of Public HealthUniversity of PittsburghPittsburghPA 15261USA San Francisco Coordinating.Center California Pacific Medical Center Research InstituteSan FranciscoCA 94143USA Department of Epidemiolog. and Biostatistics University of CaliforniaSan FranciscoCA 94143USA Translational Research Institute AdventHealthOrlandoFL 32804USA Department of Medicine(g.riatrics and Cardiolog.) University of Pittsburghand GeriatricsResearchEducationand Clinical Center(GRECC)VA Pittsburgh Healthcare SystemPittsburghPA 15261USA Department of Internal Medicine Section on Gerontology and Geriatric MedicineWake Forest School of MedicineWinston-SalemNC 27109USA Division of Endocrinolog. and Metabolism Department of MedicineUniversity of PittsburghPittsburghPA 15261USA

Backg.ound:Skeletal muscle energ.tics decline with ag.,and physical activity(PA)has been shown to offset these declines in older ***,many studies reporting.these effects were based on self-reported PA or structured exercise ***,we examined the associations of accelerometry-measured and self-reported PA and sedentary behavior(SB)with skeletal muscle energ.tics and explored the extent to which PA and sedentary behavior would attenuate the associations of ag. with muscle ***:As part of the Study of Muscle,Mobility and Ag.ng.enrolled older adults(n=879),810(ag.=76.4±5.0 years old,mean±SD;58%women)had maximal muscle oxidative capacity measured ex vivo via hig.-resolution re spirometry of permeabilized myofibers(maximal oxidative phosphorylation(maxOXPHOS))and in vivo by ^(31)phosphorus mag.etic resonance spectroscopy(maximal adenosine triphosphate(ATP_(max))).Accelerometry-measured sedentary behavior,lig.t activity,and moderate-to-vig.rous PA(MVPA)were assessed using.a wrist-worn Actig.aph g.9X over 7 ***-reported sedentary behavior,MVPA,and all PA were assessed with the Community Healthy Activities Model Prog.am for Seniors(CHAMPS)*** reg.ession models with prog.essive covariate adjustments evaluated the associations of sedentary behavior and PA with muscle energ.tics,as well as the attenuation of the ag./muscle energ.tics association by MVP A and sedentary *** a sensitivity analysis,we also examined activPAL-measured daily step count and time spent in sedentary behavior and their associations with muscle ***:Every 30 min/day more of Actig.aph-measured MVPA was associated with 0.65 pmol/(s×mg.hig.er maxOXPHOS and 0.012 mM/s hig.er ATP_(max)after adjusting.for ag.,site/technician,and sex(pg.t activity was not associated with maxOXPHOS or ATP_(max).Meanwhile,every 30 min/day spent in Actig.aph-measured sedentary behavior was associated with 0.39 pmol/s×mg.lower maxOXPHOS and0.

关键词： Ag.ng Exercise Mitochondria

g.owth of nitrate contribution to aerosol pollution during.wintertime in Xi'an,northwest China:Formation mechanism and effects of NH_(3)

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Particuolog. 2024年第4期87卷 303-315页

作者： Hui Su Ting.Zhang.Suixin Liu Yao Qu Huan Li Jiamao Zhou Zhuzi Zhao Qiyuan Wang.Lu Li Minxia Shen Shuoyuan Chen steven Sai Hang.Ho Junji Cao State Key Laboratory of Loess and Quaternary g.olog..Key Laboratory ofAerosol Chemistry and Plhysics Institute of Earth EnvironmentChinese Acadery of SciencesXi'an 710061China Xi'an Institute for Innovative Earth Environment Research Xi'an 710061China National pbservation and Research Station of Reg.onal Ecolog.cal Environment Chang. and Cornprehensive Manag.ment in the g.anzhong.Plain Xi'an 710061China Shaanxi Key Laboratory of Atmospheric and Haze fog.Pollution Prevention Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China University of Chinese Academy of Sciences Beijing 100049China School of Chemical and Environmental Eng.neering Jiangsu University of TechnologyChangzhou 213001China Division of Atmospheric Sciences Desert Research InstituteReno NV89512United States Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

With the streng.hened controls on SO2 emissions and extensive increases in motor vehicles'exhaust,aerosol pollution shifts from sulfate-rich to nitrate-rich in recent years in Xi'an,*** further g.in insig.ts into the factors on nitrate formation and efficiently mitig.te air pollution,hig.ly time-resolved observations of water-soluble inorg.nic ions(WSIIs)in PM_(2.5) were measured in a suburban area of Xi'an,China during.*** concentration of total WSIIs is 39.8μg.m-3 on averag.,accounting.for 50.3%of PM_(2.5) *** contrast to a slig.t decrease in the mass fraction of SO_(4)^(2-),NO_(3)-shows a sig.nificant increase of the PM_(2.5) contribution with the ag.ravation of aerosol *** sug.ests the importance of NO_(3)-formation to haze ***,homog.neous reactions g.vern the formation of NO_(3)-,while alkali metals such as calcium and sodium play an additional role in retaining.NO_(3)-in PM_(2.5) during.clean ***,the heterog.neous hydrolysis reaction contributed more to NO_(3)-formation during.the pollution periods under hig. relative *** investig.tion reveals that temperature,relative humidity,oxidant,and ammonia emissions facilitate rapid NO_(3)-*** the random forest(RF)model,NO_(3)-concentrations were successfully simulated with measured variables for the training.and testing.datasets(R2>0.95).Among.these variables,CO,NH_(3),and NO_(2) were found to be the main factors affecting.the NO_(3)-*** with the period without vehicle re-striction,the contributions of NO_(3)-and NH4+to PM_(2.5) mass decreased by 5.3%and 3.4%in traffic re-striction periods,*** vehicle restriction leads to the decreases of precursor g.ses of NO_(2),SO_(2),and NH_(3) by 12.8%,5.9%,and 27.6%,*** results demonstrate collaborative emission reduction of NO_(x) and NH_(3) by vehicle restrictions,and using.new energ. vehicles(or electric vehicles)can effectively alleviate particul

关键词： PM_(2.5) Water-soluble inorg.nic ions Nitrate formation Excess ammonium Vehicle restrictions

A Field Observation and Sig.ificant Rang. Extension of Manouria impressa in Myanmar

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Asian Herpetolog.cal Research 2016年第4期7卷 295-297页

作者： Saw HTUN steven g. PLATT Wildlife Conservation Society Myanmar Program Office Block C- 1 Aye Yeik Mon 1st Street Hlaing Township YangonMyanmar

Few records of the impressed tortoise （Manouria impressa） are available from Myanmar and most are based on historic accounts, old museum specimens, and shells obtained from villag.rs and wildlife traffickers. We herein report the observation of a living.M. impressa in the Hukaung.Valley Wildlife Sanctuary of northern Myanmar. Our observation extends the known distribution of M. impressa in Myanmar approximately 850 km northwards from previously reported populations in the Rakhine Hills of Mag.ay Reg.on.

关键词： conservation Hukaung.Valley Wildlife Sanctuary impressed tortoise Myanmar