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光电极表面态的静态结构与时间分辨动力学和频光谱研究

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Chinese Journal of Chemical Physics 2024年第2期37卷 376-397,I0105页

作者：张彤 Jesse B.Brown haley Fisher Mallory Liebes 皇甫至超钱余亲饶毅美国犹他州立大学化学与生物化学系犹他州洛根84322

在光催化或光电催化反应过程中,光电极的表面态扮演着重要的角色,影响着电荷的产生、分离和利用过程,从而很大程度上决定了光电极的催化性能,通常用于研究光电极表面态以改进其性能的方法是间接的、非表面特异性的以及需要超高真空条件... 详细信息

在光催化或光电催化反应过程中,光电极的表面态扮演着重要的角色,影响着电荷的产生、分离和利用过程,从而很大程度上决定了光电极的催化性能,通常用于研究光电极表面态以改进其性能的方法是间接的、非表面特异性的以及需要超高真空条件下进行的方法,无法获得真实条件下的表面态信息。电子和频光谱和电子二次谐波等非线性光学方法具有表面特异性,可以在各种条件下实现表界面系统的原位研究.本研究介绍了表面态的重要性及其与催化性能的密切关系,概述研究半导体表面态、电场和载流子动力学的方法,并重点介绍了界面特异性光谱方法在该领域的最新贡献.包括通过相位信息提取带电表面态的宽带外插法电子二次谐波技术,提供表面态动力学信息的时间分辨电子和频光谱技术和探索表面态耦合的二维电子和频光谱技术,这些非线性光学方法的进一步发展将实现对光电极表面态和界面电子特性的多角度原位表征,提供对表面态及表面电荷转移过程更深层次的理解,以启发未来光催化和光电催化材料的研究和改进.

关键词：表面态电子和频光谱光催化光电催化

The flattening of spacetime hierarchy of the n,n-dimethyltryptamine brain state is characterized by harmonic decomposition of spacetime(HADES) framework

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national Science Review 2024年第5期11卷 46-55页

作者： Jakub Vohryzek Joana Cabral Christopher Timmermann Selen Atasoy Leor Roseman David J.nutt Robin L.Carhart-harris Gustavo Deco Morten L.Kringelbach Centre for Eudaimonia and Human Flourishing Linacre CollegeDepartment of Psychiatry University of Oxford Department of Psychiatry University of Oxford Center for Music in the Brain Aarhus University Center for Brain and Cognition Computational Neuroscience GroupDepartment of Information and Communication TechnologiesUniversitat Pompeu Fabra Life and Health Sciences Research Institute School of MedicineUniversity of Minho ICVS/3B's-PT Government Associate Laboratory Centre for Psychedelic Research Department of Brain Sciences Imperial College London Departments of neurology and Psychiatry University of California San Francisco Institució Catalana de la Recerca i Estudis Avan?ats (ICREA) Department of neuropsychology Max Planck Institute for Human Cognitive and Brain Sciences School of Psychological Sciences Monash University

The human brain is a complex system, whose activity exhibits flexible and continuous reorganization across space and time. The decomposition of whole-brain recordings into harmonic modes has revealed a repertoire of gradient-like activity patterns associated with distinct brain functions. However, the way these activity patterns are expressed over time with their changes in various brain states remains unclear. Here, we investigate healthy participants taking the serotonergic psychedelic n,n-dimethyltryptamine(DMT) with the Harmonic Decomposition of Spacetime(HADES) framework that can characterize how different harmonic modes defined in space are expressed over time. HADES demonstrates significant decreases in contributions across most low-frequency harmonic modes in the DMT-induced brain state. When normalizing the contributions by condition(DMT and non-DMT), we detect a decrease specifically in the second functional harmonic, which represents the uni-to transmodal functional hierarchy of the brain,supporting the leading hypothesis that functional hierarchy is changed in psychedelics. Moreover, HADES'dynamic spacetime measures of fractional occupancy, life time and latent space provide a precise description of the significant changes of the spacetime hierarchical organization of brain activity in the psychedelic state.

关键词： spatio-temporal brain dynamics DMT harmonic modes

Exploring the associations between skeletal muscle echogenicity and physical function in aging adults:A systematic review with meta-analyses

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Journal of Sport and Health Science 2024年第6期13卷 820-840页

作者： Dustin J.Oranchuk Stephan G.Bodkin Katie L.Boncella Michael O.harris-Love Muscle Morphology Mechanicsand Performance LaboratoryDepartment of Physical Medicine and RehabilitationUniversity of Colorado Anschutz Medical CampusAuroraCO 80045USA Department of Physical Therapy

Background:Assessment and quantification of skeletal muscle within the aging population is vital for diagnosis,treatment,and injury/disease *** clinical availability of assessing muscle quality through diagnostic ultrasound presents an opportunity to be utilized as a screening tool for function-limiting ***,relationships between muscle echogenicity and clinical functional assessments require authoritative ***,we aimed to(a) synthesize the literature to assess the relationships between skeletal muscle echogenicity and physical function in older adults(≥60 years),(b) perform pooled analyses of relationships between skeletal muscle echogenicity and physical function,and(c) perform sub-analyses to determine between-muscle ***:CInAHL,Embase,MEDLInE,PubMed,and Web of Science databases were systematically searched to identify articles relating skeletal muscle echogenicity to physical function in older ***-of-bias assessments were conducted along with funnel plot ***-analyses with and without sub-analyses for individual muscles were performed utilizing Fisher's Z transformation for the most common measures of physical ***'s Z was back-transformed to Pearson's r for ***:Fifty-one articles(n=5095,female=~2759,male=~2301,72.5± 5.8 years,mean±SD(1 study did not provide sex descriptors))were extracted for review,with previously unpublished data obtained from the authors of 13 *** rectus femoris(n=34) and isometric knee extension strength(n=22) were the most accessed muscle and physical qualities,*** relationship between quadriceps echogenicity and knee extensor strength was moderate(n=2924,r=-0.36(95% confidence interval:-0.38 to-0.32),p nalyses(grip strength,walking speed,sit-to-stand,timed up-and-go) resulting in slightly weaker correlations(r:-0.34 to-0.23,all p nalyses determined minimal differences in predicti

关键词： Correlations Echo intensity Elderly Intramuscular fat Strength

北喜马拉雅萨迦穹窿中苦堆和萨迦淡色花岗岩的U-Pb年龄及其地质意义

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科学通报 2004年第20期49卷 2090-2094页

作者：张宏飞 n.harris R.Parrish 张利赵志丹中国地质大学地球科学学院武汉430074 Department of Earth Sciences The Open UniversityMilton KeynesMK76AAUK nERC Isotope Geosciences Laboratory British Geological SurveyNottinghamNG125GGUK 中国地质大学地球和资源学院北京100083

利用TIMS方法，对产于北喜马拉雅萨迦穹窿中的苦堆和萨迦淡色花岗岩锆石、独居石和磷钇矿进行了U-Pb定年．结果表明，苦堆淡色花岗岩的岩浆结晶年龄为27．5±0．5Ma，而萨迦淡色花岗岩的岩浆结晶年龄为14．4±0．2Ma，因此将北喜马拉雅... 详细信息

利用TIMS方法，对产于北喜马拉雅萨迦穹窿中的苦堆和萨迦淡色花岗岩锆石、独居石和磷钇矿进行了U-Pb定年．结果表明，苦堆淡色花岗岩的岩浆结晶年龄为27．5±0．5Ma，而萨迦淡色花岗岩的岩浆结晶年龄为14．4±0．2Ma，因此将北喜马拉雅淡色花岗岩形成的时间跨度从原有的15～10Ma扩展到27．5～10Ma，并据此对北喜马拉雅淡色花岗岩的成因机制进行了年代学制约，指出北喜马拉雅淡色花岗岩有着多样的成因机制．

关键词：淡色花岗岩喜马拉雅 U-Pb年龄地质意义穹窿岩浆成因机制方法学制利用

Estimating ancestral distributions of lineages with uncertain sister groups:a statistical approach to Dispersal-Vicariance Analysis and a case using Aesculus L.(Sapindaceae) including fossils

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Journal of Systematics and Evolution 2009年第5期47卷 349-368页

作者： A.J.harris north Carolina State University Department of Plant Biology

We propose a simple statistical approach for using Dispersal-Vicariance Analysis(DIVA) software to infer biogeographic histories without fully bifurcating *** this approach,ancestral ranges are first optimized for a sample of Bayesian *** probability P of an ancestral range r at a node is then calculated as P(rY) = n t=1 F(rY)t Pt where Y is a node,and F(rY) is the frequency of range r among all the optimal solutions resulting from DIVA optimization at node Y,t is one of n topologies optimized,and Pt is the probability of topology *** Y is a hypothesized ancestor shared by a specific crown lineage and the sister of that lineage "x",where x may vary due to phylogenetic uncertainty(polytomies and nodes with posterior probability ng this method,the ancestral distribution at Y can be estimated to provide inference of the geographic origins of the specific crown group of *** approach takes into account phylogenetic uncertainty as well as uncertainty from DIVA *** is an extension of the previously described method called Bayes-DIVA,which pairs Bayesian phylogenetic analysis with biogeographic analysis using ***,we show that the probability P of an ancestral range at Y calculated using this method does not equate to pp*F(rY) on the Bayesian consensus tree when both variables are nd F(rY) is the frequency of range r for the node containing the specific crown *** tested our DIVA-Bayes approach using Aesculus L.,which has major lineages unresolved as a *** inferred the most probable geographic origins of the five traditional sections of Aesculus and of Aesculus californica *** examined range subdivisions at parental nodes of these ***,we used the DIVA-Bayes data from Aesculus to quantify the effects on biogeographic inference of including two wildcard fossil taxa in phylogenetic *** analysis resolved the geographic ranges of the pare

关键词： Aesculus biogeography DIVA fossil wildcards MrBayes phylogenetic uncertainty.

Particle elasticity influences polymeric artificial antigen presenting cell effectiveness in vivo via CD8+T cell activation,macrophage uptake,and the protein corona

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nano Research 2024年第10期17卷 9052-9064页

作者： Savannah E.Est-Witte Sydney R.Shannon Dennis H.Gong Kaitlyn G.Calabresi Jawaun J.harris Kaitlyn Storm Edwin J.Yoo Ariel Isser Vivek P.Jani natalie K.Livingston Mary O.Omotoso Kelly Rhodes Elana Ben-Akiva Randall A.Meyer Zoe T.Hsieh Simone Sidoli Stephany Y.Tzeng Jonathan P.Schneck Jordan J.Green Translational Tissue Engineering Center Institute for NanobiotechnologyDepartment of Biomedical EngineeringJohns Hopkins School of Medicine400 N BroadwayBaltimoreMD 21231USA Institute for Cell Engineering Department of PathologyJohns Hopkins School of Medicine733 N BroadwayBaltimoreMD 21205USA Department of Biochemistry Albert Einstein College of MedicineThe BronxNew York CityNY 10461USA

Adoptive cell therapy(ACT)is an immunotherapy strategy for cancer that has seen widespread clinical *** ACT,patient-derived lymphocytes are stimulated with the antigen of interest ex vivo,proliferated,then returned to the patient to initiate an antigen-specific antitumor *** effective,this process is resource-intensive and logistically impossible for many *** artificial antigen presenting cells(aAPCs)offer a potential“off-the-shelf”alternative to ex vivo *** particulate aAPCs perform well in vitro,they have had limited success in vivo due to poor bioavailability after *** to bioavailability include rapid clearance,unfavorable biodistribution,and inadequate interactions with CD8+T cells at sites of *** properties such as elasticity have been shown to vastly impact the bioavailability and particle-cell interactions,but this has yet to be investigated in the context of aAPCs for in vivo T-cell *** literature likewise indicates that biomaterial properties,especially elasticity,can modulate T-cell activation in *** the goal of creating a more biomimetic,next-generation particulate aAPC,we developed a poly(ethylene)glycol hydrogel particle platform with tunable elasticity to investigate the impact of elasticity on antigen-specific T cell activation for in vivo adoptive *** this knowledge,we were able to gain more precise control over in vivo T cell activation and investigate possible mechanisms including the effects of aAPC elasticity on T cell binding,macrophage uptake,and the protein corona.

关键词： adoptive cell therapy artificial antigen presenting cells particle drug delivery elasticity protein corona poly(ethylene glycol)

Cryogenic wedges on the nE Qinghai-Tibet and Ordos Plateaus:Their characteristics,origin and OSL dating

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Research in Cold and Arid Regions 2021年第6期13卷 463-473页

作者： Stuart A.harris Department of Geography University of CalgaryCalgaryAlbertaT2N 1N4Canada

Cryogenic wedges developed due to very cold,rather arid conditions during the maximum of the last cold event when the drying up of the neighboring China Sea resulted in the failure of the East Asian *** the climate ameliorated and the Monsoon rains reappeared,ice-wedges *** warming permitted thawing of the ice infillings accompanied by replacement of the ice by sediments partly from the host ground as well as from the surface by wind or sheet *** cases of extreme surface water flow on slopes after 10 ka B.P.,small baydjarakhs typically c.50 cm high developed,only to have the resulting hollows infilled by sediments carried by wind and/or sheet *** shallow structures form a network on top of many of the cryogenic *** complex history makes dating the ages of the wedges difficult using OSL ***,past field work ignored the problem of the angle of the cut face to the direction of the wedge infilling when sampling the contents of the narrow wedges,resulting in potential contamination of the samples with the host *** of the larger deposits should be alright,but the likelihood of contamination makes the interpretation of the resulting OSL dates from the narrow wedges *** wedges consisting of primary mineral infillings should still have similar OSL dates with depth for a given wedge,but the distinction between ice-wedge infillings and soil wedges is difficult since both can exhibit older dates of the infillings with *** available data suggests that ice-wedges were significantly more common than sediment-filled primary wedges.A protocol to avoid having to obtain large numbers of OSL dates by more careful field sampling and the use of grain size determinations is provided in the Appendix.

关键词： cryogenic wedges OSL dating nE Qinghai-Tibet Plateau differentiation of primary and secondary wedges baydjarakhs in arid climates

Strong observability as a sufficient condition for non-singularity and lossless convexification in optimal control with mixed constraints

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Control Theory and Technology 2022年第4期20卷 475-487页

作者： Sheril Kunhippurayil Matthew W.harris Torc Robotics Inc.405 Partnership DriveBlacksburg 24060VirginiaUSA Department of Mechanical and Aerospace Engineering Utah State University4130 Old Main HillLogan 84322UtahUSA

This paper analyzes optimal control problems with linear time-varying dynamics defined on a smooth manifold in addition to mixed constraints and pure control *** main contribution is the identification of sufficient conditions for the optimal controls to be non-singular,which enables exact(or lossless)convex relaxations of the control *** problem is analyzed in a geometric framework using a recent maximum principle on manifolds,and it is shown that strong observability of the dual system on the cotangent space is the key *** minimum time problems are analyzed and solved.A minimum fuel planetary descent problem is then analyzed and relaxed to a convex *** enables its efficient solution in less than one second without any initial guess.

关键词： Optimal control Strong observability Lossless convexification

Prospective,multicentre study of screening,investigation and management of hyponatraemia after subarachnoid haemorrhage in the UK and Ireland

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Stroke & Vascular neurology 2023年第3期8卷 207-216,I0028-I0059页

作者： James J M Loan Steven Tominey Kirun Baweja Julie Woodfield Thomas J G Chambers Mark haley Simran S Kundu H Y Josephine Tang Anthony n Wiggins Michael T C Poon Paul M Brennan Translational neurosurgery The University of Edinburgh Centre for Clinical Brain SciencesEdinburghUK neurosurgery NHS LothianEdinburghUK neurosurgery Institute of Neurological SciencesGlasgowUK Department of Medicine School of MedicineDentisty and NuringUniversity of GlasgowGlasgowUK Internal Medicine Queen's UniversityKingstonOntarioCanada Centre for Discovery Brain Sciences University of EdinburghEdinburghUK Edinburgh Centre for Diabetes and Endocrinology NHS LothianEdinburghUK Radiology University Hospitals Plymouth NHS TrustPlymouthUK Department of Medicine Cork University HospitalUniversity College CorkCorkIreland

Background Hyponatraemia often occurs after subarachnoid haemorrhage(SAH).However,its clinical significance and optimal management are *** audited the screening,investigation and management of hyponatraemia after *** We prospectively identified consecutive patients with spontaneous SAH admitted to neurosurgical units in the United Kingdom or *** reviewed medical records daily from admission to discharge,21 days or death and extracted all measurements of serum sodium to identify hyponatraemia(n outcomes were death/dependency at discharge or 21 days and admission duration>10 *** of hyponatraemia with outcome were assessed using logistic regression with adjustment for predictors of outcome after SAH and admission *** assessed hyponatraemia-free survival using multivariable Cox *** 175/407(43%)patients admitted to 24 neurosurgical units developed hyponatraemia.5976 serum sodium measurements were *** osmolality,urine osmolality and urine sodium were measured in 30/166(18%)hyponatraemic patients with complete *** most frequently target daily fluid intake was>3 L and this did not differ during hyponatraemic or non-hyponatraemic episodes.26%(n/n=42/164)patients with hyponatraemia received sodium supplementation.133(35%)patients were dead or dependent within the study period and 240(68%)patients had hospital admission for over 10 *** the multivariable analyses,hyponatraemia was associated with less dependency(adjusted OR(aOR)=0.35(95%CI 0.17 to 0.69))but longer admissions(aOR=3.2(1.8 to 5.7)).World Federation of neurosurgical Societies grade I-III,modified Fisher 2-4 and posterior circulation aneurysms were associated with greater hazards of *** In this comprehensive multicentre prospective-adjusted analysis of patients with SAH,hyponatraemia was investigated inconsistently and,for most patients,was not associated with changes in management or clinical outcome.T

关键词： admitted urine centre