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The application of aromaticity and antiaromaticity to reaction mechanisms

Fundamental Research 2023年第6期3卷 926-938页

作者： Qin Zhu Shuwen Chen Dandan Chen Lu Lin Kui Xiao Liang Zhao miquel Solà Jun Zhu State Key Laboratory of Physical Chemistry of Solid Surfaces and Collaborative Innovation Center of Chemistry for Energy Materials(iChEM) College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Key Laboratory for Organic Electronics&Information Displays(KLOEID)and Institute of Advanced Materials(IAM) SICAMNanjing University of Posts&TelecommunicationsNanjing 210023China Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China Institute of Computational Chemistry and Catalysis and Department of Chemistry University of GironaC/M.Aurèlia Capmany6917003 GironaCataloniaSpain School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China

Aromaticity,in general,can promote a given reaction by stabilizing a transition state or a product via a mobility ofπelectrons in a cyclic ***,such a promotion could be also achieved by destabilizing an antiaromatic ***,both aromaticity and transition states cannot be directly measured in ***,computational chemistry has been becoming a key tool to understand the aromaticity-driven reaction *** this review,we will analyze the relationship between aromaticity and reaction mechanism to highlight the importance of density functional theory calculations and present it according to an approach via either aromatizing a transition state/product or destabilizing a reactant by ***,we will start with a particularly challenging example of dinitrogen activation followed by other small-molecule activation,Csingle bondF bond activation,rearrangement,as well as metathesis *** addition,antiaromaticity-promoted dihydrogen activation,CO_(2)capture,and oxygen reduction reactions will be also briefly ***,caution must be cast as the magnitude of the aromaticity in the transition states is not particularly high in most ***,a proof of an adequate electron delocalization rather than a complete ring current is recommended to support the relatively weak aromaticity in these transition states.

关键词： Aromaticity Antiaromaticity Reaction mechanism Frustrated Lewis pairs Dinitrogen activation Small molecule activation

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风生紊流导致微囊藻群体破碎和形态变化

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湖泊科学 2021年第2期33卷 349-365页

作者：朱伟陈怀民肖曼 Lürling miquel 李明河海大学环境学院浅水湖泊综合治理与资源开发教育部重点实验室南京210098 格里菲斯大学澳大利亚河流研究所澳大利亚昆士兰州4111 瓦格宁根大学环境科学系水生态及水质管理组荷兰瓦格宁根6700AA 西北农林科技大学资源环境学院杨凌712100

微囊藻群体大小和形态决定其垂向迁移能力,从而影响着水华的形成.为了探讨湖泊中风生紊流对微囊藻群体大小和形态的影响,本研究于2012年8月26日至9月7日在太湖梅梁湾的围隔内进行了12 d的昼夜不间断的高频采样(采样间隔每2小时一次).研... 详细信息

微囊藻群体大小和形态决定其垂向迁移能力,从而影响着水华的形成.为了探讨湖泊中风生紊流对微囊藻群体大小和形态的影响,本研究于2012年8月26日至9月7日在太湖梅梁湾的围隔内进行了12 d的昼夜不间断的高频采样(采样间隔每2小时一次).研究期间,水面微囊藻密度呈现4次周期性消涨,藻密度变化范围为4×10^(4)~2671×10^(4)cells/m L.而整个水柱中的藻密度变化范围仅为3×10^(4)~18×10^(4)cells/m L.皮尔逊相关性分析表明微囊藻的原位生长速率与表面藻密度呈负相关而与风速呈正相关.强风速使微囊藻在水柱中均匀分散,增强了透光性,促进了微囊藻的生长.微囊藻群体粒径随着风速的增大逐渐减小,反之亦然.其中值粒径(D50)变化范围为66.2~768.0μm.在此期间微囊藻群体形态主要以鱼害微囊藻、不规则的惠氏微囊藻、球状的惠氏微囊藻和铜绿微囊藻群体形态为主,其占比也呈现出波动状态.皮尔逊相关分析结果显示微囊藻群体大小与风速呈负相关,说明湖泊中风生紊流会影响微囊藻群体大小.当紊流强度为2.33×10^(-5)m^(2)/s3时,微囊藻群体会发生破碎现象,该紊流强度相当于5 m/s的风在30 m深的水库或湖泊中所产生的紊流强度.微囊藻群体被风生紊流破碎后最大粒径与该风速下紊流的最小涡旋尺度相近,表明紊流的最小涡旋尺度决定了微囊藻所能形成群体的最终大小.监测期间,整水柱中不同群体形态的微囊藻占比发生了明显变化,在监测初期以鱼害微囊藻群体形态为主,随后不规则的惠氏微囊藻和铜绿微囊藻群体形态的比例不断增加,最后鱼害微囊藻群体形态又占据主导地位.球状的惠氏微囊藻群体形态在整个监测期中的比例随时间的增加而逐渐降低.不同群体形态微囊藻之间比例的大幅变化无法用微囊藻生长演替来解释.而皮尔逊相关分析结果显示鱼害微囊藻与惠氏微囊藻(不规则的和球状的惠氏微囊藻之和)群体形态之间存在负相关,且惠氏微囊藻与铜绿微囊藻群体形态呈负相关.但在今后研究中需进一步关注在微囊藻群体形态的动态变化过程中细胞大小、胶被、产毒特性和基因序列等特征,从而验证不同种微囊藻群体是否存在形态转换这一猜想.总而言之,普通强度的风生紊流能够破碎微囊藻群体,而气候变化导致的内陆湖泊周边风速下降会促使微囊藻形成更大的群体,从而有利于水华的形成.

关键词：微囊藻水华紊流群体粒径形态太湖

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Familial aggregation in inflammatory bowel disease:Is it genes or environment?

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World Journal of Gastroenterology 2011年第22期17卷 2715-2722页

作者： Tiago Nunes Gionata Fiorino Silvio Danese miquel Sans Department of Gastroenterology Hospital Clinic i Provincial/IDIBAPS CIBER EHD 08036 Barcelona Spain Division of Gastroenterology IRCCS Istituto Clinico Humanitas Rozzano Milan 20089 Italy

Inflammatory bowel disease (IBD) develops in genetically susceptible individuals due to the influence of environmental factors, leading to an abnormal recognition of microbiota antigens by the innate immune system which triggers an exaggerated immune response and subsequent bowel tissue damage. IBD has been more frequently found in families, an observation that could be due to either genetic, environmental or both types of factors present in these families. In addition to expanding our knowledge on IBD pathogenesis, defining the specific contribution to familial IBD of each one of these factors might have also clinical usefulness. We review the available evidence on familial IBD pathogenesis.

关键词： Inflammatory bowel disease Familial aggregation Familial clustering Environmental factors Genetics Genome wide association studies

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No Effects of Meteorological Factors on the SARS-CoV-2 Infection Fatality Rate

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Biomedical and Environmental Sciences 2021年第11期34卷 871-880页

作者： SOLANES Aleix LAREDO Carlos GUASP Mar FULLANA miquel Angel FORTEA Lydia GARCIA-OLIVE Ignasi SOLMI Marco SHIN Jae II URRA Xabier RADUA Joaquim Institut d'lnvestigacions Biomediques August Pi i Sunyer(IDIBAPS) BarcelonaSpain Department of Psychiatry and Forensic Medicine Autonomous University of BarcelonaBarcelonaSpain Neurosciences Unit Hospital ClinicBarcelonaSpain Adult Psychiatry and Psychology Department Institute of NeurosciencesHospital ClinicBarcelonaSpain Biomedical Network Research Centre on Mental Health(CIBERSAM) Instituto de Salud Carlos IIIMadridSpain Department of Medicine University of BarcelonaBarcelonaSpain Department of Medicine Autonomous University of BarcelonaBarcelonaSpain Pneumology Department Hospital Germans Trias i PujolBadalonaSpain Neurosciences Department University of PaduaPaduaItaly Padua Neuroscience Center PaduaItaly Department of Psychosis Studies Institute of PsychiatryPsychology and NeuroscienceKing's College LondonLondonUK Department of Pediatrics College of MedicineYonsei UniversitySeoul 03722Korea Centre for Psychiatric Research and Education Department of Clinical NeuroscienceKarolinska InstitutetStockholmSweden

Objective Previous studies have shown that meteorological factors may increase COVID-19 mortality,likely due to the increased transmission of the ***,this could also be related to an increased infection fatality rate(IFR).We investigated the association between meteorological factors(temperature,humidity,solar irradiance,pressure,wind,precipitation,cloud coverage)and IFR across Spanish provinces(n=52)during the first wave of the pandemic(weeks 10–16 of 2020).Methods We estimated IFR as excess deaths(the gap between observed and expected deaths,considering COVID-19-unrelated deaths prevented by lockdown measures)divided by the number of infections(SARS-CoV-2 seropositive individuals plus excess deaths)and conducted Spearman correlations between meteorological factors and IFR across the *** We estimated 2,418,250 infections and 43,237 *** IFR was 0.03%in<50-year-old,0.22%in 50–59-year-old,0.9%in 60–69-year-old,3.3%in 70–79-year-old,12.6%in 80–89-year-old,and26.5%in≥*** did not find statistically significant relationships between meteorological factors and adjusted ***,we found strong relationships between low temperature and unadjusted IFR,likely due to Spain’s colder provinces’aging *** The association between meteorological factors and adjusted COVID-19 IFR is *** age differences or ignoring COVID-19-unrelated deaths may severely bias COVID-19 epidemiological analyses.

关键词： Climate COVID-19 Infection fatality rate SARS-CoV-2 Temperature Weather

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Role of T cell death in maintaining immune tolerance during persistent viral hepatitis

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World Journal of Gastroenterology 2013年第12期19卷 1877-1889页

作者： Juan Ramón Larrubia Megha Uttam Lokhande Silvia García-Garzón Joaquín miquel Dolores Subirá Eduardo Sanz-de-Villalobos Translational Hepatology Unit Guadalajara University Hospital University of Alcalá

Virus-specific T cells play an important role in the resolution of hepatic infection. However, during chronic hepatitis infection these cells lack their effector functions and fail to control the virus. Hepatitis B virus and hepatitis C virus have developed several mechanisms to generate immune tolerance. One of these strategies is the depletion of virus-specific T cells by apoptosis. The immunotolerogenic liver has unique property to retain and activate na ve T cell to avoid the over reactivation of immune response against antigens which is exploited by hepatotropic viruses to persist. The deletion of the virus-specific T cells occurs by intrinsic (passive) apoptotic mechanism. The pro-apoptotic molecule Bcl-2 interacting mediator (Bim) has attracted increasing attention as a pivotal involvement in apoptosis, as a regulator of tissue homeostasis and an enhancer for the viral persistence. Here, we reviewed our current knowledge on the evidence showing critical role of Bim in viral-specific T cell death by apoptotic pathways and helps in the immune tolerance.

关键词： T cell death Specific cytotoxic T lymphocytes Hepatitis C virus immune tolerance Apoptosis Bcl-2 interacting mediator Liver tolerance Apoptotic pathways Viral hepatitis

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Tumor necrosis family receptor superfamily member 9/tumor necrosis factor receptor-associated f

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World Journal of Hepatology 2020年第10期12卷 754-765页

作者： Julia Peña-Asensio Eduardo Sanz-de-Villalobos Joaquín miquel Juan Ramón Larrubia Department of Systems Biology Guadalajara University Hospital.University of AlcaláGuadalajara E-19002GuadalajaraSpain Translational Hepatology Unit Guadalajara University HospitalUniversity of AlcaláGuadalajara E-19002GuadalajaraSpain

Hepatitis C virus(HCV)infection is an excellent immunological model for understanding the mechanisms developed by non-cytopathic viruses and tumors to evade the adaptative immune *** antigen-specific cytotoxic T cell response is essential for keeping HCV under control,but during persistent infection,these cells become exhausted or even *** exhaustion process is progressive and depends on the infection duration and level of *** high antigenic load and long duration of infection,T cells become extremely exhausted and ultimately disappear due to *** development of exhaustion involves the impairment of positive co-stimulation induced by regulatory cytokines,such as transforming growth factor beta *** cytokine downregulates tumor necrosis factor receptor(TNFR)-associated factor 1(TRAF1),the signal transducer of the T cell co-stimulatory molecule TNFR superfamily member 9(known as 4-1BB).This impairment correlates with the low reactivity of T cells and an exhaustion *** with interleukin-7 in vitro restores TRAF1 expression and rescues T cell effector *** process of TRAF1 loss and its in vitro recovery is hierarchical,and more affected by severe disease *** conclusion,TRAF1 dynamics on T cells define a new pathogenic model that describes some aspects of the natural history of HCV,and sheds light on novel immunotherapy strategies for chronic viral infections and cancer.

关键词： Hepatitis C virus Tumor necrosis factor receptor-associated factor 1 CD8 Exhaustion Tumor necrosis family receptor superfamily member 9 Chronic hepatitis

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Degradation of Cymodocea nodosa(Ucria)Ascherson meadow at Las Canteras Beach(Gran Canaria,Canary Islands,Atlantic Ocean)

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Journal of Coastal Life Medicine 2014年第4期 270-273页

作者： Milena Polifrone miquel Rosell-Fieschi Departamento de Biología Universidad de Las Palmas de Gran Canaria-Campus Universitario de Tafira35017 Las PalmasCanary IslandsSpain

Objective:To monitor the distribution of Cymodocea nodosa(Ucria)Ascherson in Las Canteras Beach(Las Palmas de Gran Canaria,Spain),comparing the status in 2005 with the distribution observed in 1985 and ***:Field observations by selfcontained underwater breathing apparatus diving records and cartographic ***:The seagrass meadow originally distributed between the beach and a bar of volcanic rocks,which sheltered it from the strong north-east winds and *** 1985 a gradual reduction of its extent has been observed and more than 80%of the original canopy disappeared in twenty years time,mostly due to the anthropogenic impact and modification of the sedimentary dynamics of the ***:The degradation of this seagrass meadow determinates the loss of the only meadow in the north of the island of Gran Canaria and the absence of a management plan for its conservation.

关键词： Anthropogenic impact Conservation biology Cymodocea nodosa Distribution Seagrasses Sediment burial

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Neuroimaging studies of cognitive remediation in schizophrenia:A systematic and critical review

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World Journal of Psychiatry 2017年第1期7卷 34-43页

作者： Rafael Penadés Alexandre González-Rodríguez Rosa Catalán Bàrbara Segura miquel Bernardo Carme Junqué Department of Psychiatry and Psychology Clinical Institute of NeurosciencesHospital Clínic Neuropsychology Lab University of Barcelona Institut d’Investigacions Biomèdiques August Pi i Sunyer

AIM To examine the effects of cognitive remediation therapies on brain functioning through neuroimaging procedures in patients with *** A systematic, computerised literature search was conducted in the PubM ed/Medline and PsychI nfo databases. The search was performed through February 2016 without any restrictions on language or publication date. The search was performed using the following search terms: [("cogniti*" and "remediation" or "training" or "enhancement") and("fMRI" or "MRI" or "PET" or "SPECT") and(schizophrenia or schiz*)]. The search was accompanied by a manual online search and a review of the references from each of the papers selected, and those papers fulfilling our inclusion criteria were also *** A total of 101 studies were found, but only 18 of them fulfilled the inclusion criteria. These studies indicated that cognitive remediation improves brain activation in neuroimaging studies. The most commonly reported changes were those that involved the prefrontal and thalamic regions. Those findings are in agreement with the hypofrontality hypothesis, which proposes that frontal hypoactivation is the underlying mechanism of cognitive impairments in schizophrenia. Nonetheless,great heterogeneity among the studies was found. They presented different hypotheses, different results and different findings. The results of more recent studies interpreted cognitive recovery within broader frameworks, namely, as amelioration of the efficiency of different networks. Furthermore, advances in neuroimaging methodologies, such as the use of wholebrain analysis, tractography, graph analysis, and other sophisticated methodologies of data processing, might be conditioning the interpretation of results and generating new theoretical frameworks. Additionally, structural changes were described in both the grey and white matter, suggesting a neuroprotective effect of cognitive remediation. Cognitive, functional and structural improvements tend

关键词： Cognitive remediation Cognitive training Neuroimaging Cognition Prefrontal cortex Thalamus Plasticity Schizophrenia

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Adaptive immune response during hepatitis C virus infection

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World Journal of Gastroenterology 2014年第13期20卷 3418-3430页

作者： Juan Ramon Larrubia Elia Moreno-Cubero Megha Uttam Lokhande Silvia Garcia-Garzon Alicia Lazaro Joaquin miquel Cristian Perna Eduardo Sanz-de-Villalobos Translational Hepatology Unit Guadalajara University HospitalUniversity of AlcalaE-19002 GuadalajaraSpain Department of Medicine and Medical Specialities School of MedicineUniversity of AlcalaE-28801 Alcala de HenaresSpain

Hepatitis C virus(HCV)infection affects about 170 million people worldwide and it is a major cause of liver cirrhosis and hepatocellular *** is a hepatotropic non-cytopathic virus able to persist in a great percentage of infected hosts due to its ability to escape from the immune *** damage and disease progression during HCV infection are driven by both viral and host ***,adaptive immune response carries out an essential task in controllingnon-cytopathic viruses because of its ability to recognize infected cells and to destroy them by cytopathic mechanisms and to eliminate the virus by non-cytolytic *** is able to impair this response by several means such as developing escape mutations in neutralizing antibodies and in T cell receptor viral epitope recognition sites and inducing HCV-specific cytotoxic T cell anergy and *** impair HCV-specific T cell reactivity,HCV affects effector T cell regulation by modulating T helper and Treg response and by impairing the balance between positive and negative co-stimulatory molecules and between pro-and antiapoptotic *** this review,the role of adaptive immune response in controlling HCV infection and the HCV mechanisms to evade this response are reviewed.

关键词： Hepatitis C, Adaptive immune response, Hepatitis C virus-specific cytotoxic T cells, Hepatitis C virus-specific T helper cells, T regs, Hepatitis C virus escape mutations, Anergy, Apoptosis, Chemotaxis

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Nonlinear Magnetoimpedance Effect in FeCoNi Ferromagnetic Tubes

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Chinese Physics Letters 2001年第9期18卷 1268-1270页

作者： G.V.Kurlyandskaya H.Yakabchuk E.Kisker N.G.Bebenin H.García-miquel M.Vázquez V.O.Vas′kovskiy Dpto.de Eiectricidad y Electrica Universidad del Pa Vasco UPV-EHU Apdo 64448080 BilbaoSpain Institut fiir Angewandte Physik Heinrich Heine Universitat DiisseldorfUniversitatstraβe 1Bld.25.33.01.24D-40225DiisseldorfGermany Institute of Metal Physics UD RAS Kovalevskaya str.18GSP-170620219 EkaterinburgRussia Dpto.de Ing.Electronica Universidad Poiitecnica de ValenciaCamino de Veras/n46022 ValenciaSpain Instituto de Ciencia de Materiaies CSICP.O.Box 15528230 Las Rozas(Madrid)Spain Institute of Physics and Applied Mathematics Ural State UniversityLenin Ave.51620083 EkaterinburgRussia

The very high (up to 820% of the magnetoimpedance ratio) and sensitive nonlinear giant magnetoimpedance effect has been studied in the FeCo1Ni magnetic tubes electroplated onto Cu(3%)Be nonmagnetic wirefor frequencies from 1-10MHz. Special annealing was carried out in order to induce the magnetic anisotropy. The high harmonic generation was observed and the harmonics show larger variations with the external magnetic field than the fundamental frequency. The super high sensitivity of the harmonics is promising as regards the increase of the sensitivity of magnetoimpedance sensors.

关键词： harmonics magnetic impedance

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