检索结果-南通市图书馆

NHC-catalysed[3+2]-asymmetric annulation between pyrazolin-4,5-diones and enals:synthesis of novel spirocyclic pyrazolone γ-butyrolactones and computational study of mechanism and stereoselectivity

在线全文

学校读者我要写书评

暂无评论

Organic Chemistry Frontiers 2022年第2期9卷 420-427页

作者： Marta gil-Ordonez Alicia Maestro pablo ortega pablo g.Jambrina Jose M.Andres gIR-SintACat-Instituto Universitario CINQUIMA y Departamento de Química Orgánica Facultad de CienciasUniversidad de ValladolidPaseo Belén 747011 ValladolidSpain Departamento de Química Física University of Salamanca37008 SalamancaSpain

Chiral pyrazolones with a spirocyclic centre at the C4-position are widely found in a large family of medically relevant *** recent years,organocatalysis,particularly that performed with quiral N-heterocyclic carbenes(NHCs),has allowed the enantioselective synthesis of these spirocyclic compounds despite its inherent *** this work,we describe the fully diastereo-and highly enantioselective synthesis of novel spirocyclic pyrazolone γ-butyrolactones via NHC-catalysed[3+2]annulation reaction of enals and 1H-pyrazol-4,*** understand the catalytic mechanism and origin of stereoselectivity,electronic structure calculations were carried *** considering various pathways,we concluded that the stereoselectivity-determining step is the formation of the lactone that proceeds after addition of the NHC derived homoenolate to the electrophilic carbonyl group of pyrazolin-4,*** calculations predict that the free energy barrier is lower for the(RS)product,which is also the main product experimentally obtained.

关键词： synthesis spiro mechanism

Self-powered smart patch for sweatconductivity monitoring

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Microsystems & Nanoengineering 2019年第1期5卷 672-681页

作者： Laura ortega Anna Llorella Juan pablo Esquivel Neus Sabate Instituto de Microelectronica de Barcelona IMB-CNM(CSIC)C/del Til·lers.Campus Universitat Autonoma de Barcelona(UAB)08193 BellaterraBarcelonaSpain Catalan Institution for Research and Advanced Studies(ICREA) Passeig Lluís Companys 2308010 BarcelonaSpain

A self-powered skin patch for the measurement of sweat conductivity is *** key component of the patch consists of a paper battery that is activated upon absorption of *** body fluid acts as the battery electrolyte,the conductivity of which has a direct impact on the battery-generated output power and *** particular behaviour enables the operation of a very simple and robust conductivity sensor in direct current mode without needing an external power *** device presented in this paper takes advantage of this new measurement method to develop a sweat patch for screening cystic fibrosis that operates with an extremely simple electronic circuit that minimizes its cost and environmental *** patch provides an unambiguous digital result that can be read in an electrochromic display and yields 95%sensitivity and 100%specificity when tested with artificial eccrine perspiration samples.

关键词： battery conductivity patch

Hepatic arterial infusion of gemcitabine-oxaliplatin in a large metastasis from colon cancer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of gastroenterology 2010年第9期16卷 1150-1154页

作者： Boris guiu Julie Vincent Séverine guiu Sylvain Ladoire pablo ortega-Deballon Jean-Pierre Cercueil Bruno Chauffert Franois ghiringhelli Department of Radiology INSERM U866University of BurgundyUniversity Hospital Department of Hepatology INSERM U866University of BurgundyUniversity Hospital Department of Oncology INSERM U866AVENIR TeamUniversity of Burgundy Department of Digestive Surgery INSERM U866University of BurgundyUniversity Hospital

Hepatic arterial infusion (HAI) of chemotherapy can be performed in cases of liver-confined metastatic disease,resulting in increased local drug *** we report the case of a 61-year-old man who presented with an isolated large unresectable liver metastasis of colon cancer after failure of surgery and multiple administration of systemic *** patient was treated with a combination of gemcitabine and oxaliplatin using *** tolerance was excellent and a radiological complete response was obtained after 8 cycles of *** rationale for the use of gemcitabine and oxaliplatin as well as that for the combination of the 2 drugs is discussed in this *** of gemcitabine-oxaliplatin should be evaluated in further clinical trials.

关键词： Hepatic artery Chemotherapy Colon cancer Liver metastasis gemcitabine Oxaliplatin Contrast media Computed tomography

Lessons learned from requirements gathering for virtual reality simulators

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Virtual Reality & Intelligent Hardware 2021年第5期3卷 407-422页

作者： Vivian gÓMEZ Kelly PEÑARANDA pablo FIgUEROA Department of Systems and Computing Engineering Universidad de Los AndesBogotá7620001Colombia

Background This paper shows how current collaborative virtual environments(VEs)such as Mozilla Hubs and AltspaceVR can aid in the task of requirements gathering in VR for simulation and *** We performed a qualitative study on our use of these technologies in the requirements gathering of two *** Our results show that requirements gathering in virtual reality has an impact on the process of requirements *** report advantages and shortcomings that will be of interest to future *** example,we found that VR sessions for requirements gathering in current VEs could benefit from better pointers and better sound *** Current VEs are useful for the requirements gathering task in the development of VR simulators and VR training environments.

关键词： Human computer interaction Virtual environment Requirements gathering globally dispersed teams VR simulators and training

Physical activity and amyloid beta in middle-aged and older adults:A systematic review and meta-analysis

在线全文

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2024年第2期13卷 133-144页

作者： María Rodriguez-Ayllon Patricio Solis-Urra Cristina Arroyo-ávila Miriam álvarez-ortega pablo Molina-garcía Cristina Molina-Hidalgo Manuel gómez-Río Belinda Brown Kirk I.Erickson Irene Esteban-Cornejo Department of Epidemiology Erasmus University Medical Center RotterdamRotterdamGD 3015the Netherlands Department of Physical Education and Sports Faculty of Sport SciencesSport and Health University Research Institute(iMUDS)University of GranadaGranada 18071Spain Faculty of Education and Social Sciences Universidad Andres BelloVina del Mar 2531015Chile Department of Nuclear Medicine Virgen de las Nieves University HospitalInstitute of Biosanitary Research of Granada(IBS)Granada 18014Spain Physical Medicine and Rehabilitation Service Virgen de las Nieves University HospitalInstitute of Biosanitary Research of Granada(IBS)Granada 18014Spain Department of Psychology University of PittsburghPittsburghPA 15260USA Centre for Healthy Ageing Health Futures InstituteMurdoch UniversityMurdochWA 6150Australia School of Medical and Health Sciences Edith Cowan UniversityJoondalupWA 6027Australia Advent Health Research Institute Neuroscience Institute OrlandoOrlandoFL 32803USA Physiopathology of Obesity and Nutrition Research Center(CIBERobn) Institute of Health Carlos Ⅲ(ISCⅢ)Madrid 28029Spain

Background:One of the pathological hallmarks distinguishing Alzheimer’s disease from other dementias is the accumulation of amyloid beta(Aβ).Higher physical activity is associated with decreased dementia risk,and one potential path could be through Aβlevels *** aimed to explore the relationship between physical activity and Aβin middle-aged and older ***:A systematic search of PubMed,Web of Science,PsycINFO,Cochrane Central Register of Controlled Trials,and SPORTDiscus was performed from inception to April 28,*** were eligible if they included physical activity and Aβdata in adults aged 45 years or ***-level metaanalyses of intervention and observational studies were performed to examine the role of physical activity in modulating Aβ***:In total,37 articles were included(8 randomized controlled trials,3 non-randomized controlled trials,4 prospective longitudinal studies,and 22 cross-sectional studies).The overall effect size of physical activity interventions on changes in blood Aβwas medium(pooled standardized mean difference=-0.69,95%confidence interval(95%CI):-1.41 to 0.03;I^(2)=74.6%).However,these results were not statistically significant,and there were not enough studies to explore the effects of physical activity on cerebrospinal fluid(CSF)and brain Aβ.Data from observational studies were examined based on measurements of Aβin the brain using positron emission tomography scans,CSF,and *** physical activity was positively associated with Aβonly in the CSF(Estimate r=0.12;95%CI:0.05-0.18;I^(2)=38.00%).Conclusion:Physical activity might moderately reduce blood Aβin middle-aged and older ***,results were only near statistical significance and might be interpreted with caution given the methodological limitations observed in some of the included *** observational studies,higher levels of physical activity were positively associated with Aβonly in ***,further research is needed t

关键词： Aging Cognitive impairment Dementia Exercise PET

Chemokines and Chemokine Receptors:Their Manifold Roles in Homeostasis and Disease

在线全文

学校读者我要写书评

暂无评论

Cellular & Molecular Immunology 2004年第2期1卷 95-104页

作者： pablo Iribarren Laboratory of Molecular Immunoregulation Center for Cancer ResearchNational Cancer Institute at FrederickFrederickMarylandUSA

Chemokines are a superfamily of small proteins that bind to g protein-coupled receptors on target cells and were originally discovered as mediators of directional migration of immune cells to sites of inflammation and *** recent years,it has become clear that the function of chemokines extends well beyond the role in leukocyte *** participate in organ development,angiogenesis/angiostasis,leukocyte trafficking and homing,tumorigenesis and metastasis,as well as in immune responses to microbial ***, chemokines and their receptors are important targets for modulation of host responses in pathophysiologicai conditions and for therapeutic intervention of human *** & Molecular Immunology.2004;1(2): 95-104.

关键词： chemokine receptor development leukocyte homing angiogenesis metastasis

Chitosan Nanoparticles as Biostimulant in Lettuce (Lactuca sativa L.) Plants

在线全文

学校读者我要写书评

暂无评论

Phyton-International Journal of Experimental Botany 2024年第4期93卷 777-787页

作者： Silvia C.Ramírez-Rodríguez pablo Preciado-Rangel Marcelino Cabrera-De La Fuente Susana gonzález-Morales Hortensia ortega-Ortiz Tecnológico Nacional de México Instituto Tecnológico de TorreónEjido AnaTorreónCoahuila27170México Departamento de Horticultura Universidad Autónoma Agraria Antonio NarroSaltillo25315México Departamento de Materiales Avanzados Centro de Investigación en Química AplicadaSaltilloCoahuila25294México

Biodegradable nanoparticles such as chitosan nanoparticles (CSNPs) are used in sustainable agriculture since theyavoid damage to the environment;CSNPs have positive effects such as the accumulation of bioactive compoundsand increased productivity in plants. This study aimed to investigate the impact of applying CSNPs on lettuce,specifically focusing on enzymatic activity, bioactive compounds, and yield. The trial was conducted using a completelyrandomized design, incorporating CSNPs: 0, 0.05, 0.1, 0.2, 0.4, and 0.8 mg mL−1. The doses of 0.4 mg mL−1improve yields up to 24.6% increases and 0.1 mg mL−1 of CSNPs increases total phenols by 31.2% and antioxidantcapacity by 34.6%. In addition, when low concentrations of CSNPs (0.05 and 0.1 mg L−1) were applied, anincrease in catalase was determined. The CSNPs represent a good alternative to be used as a biostimulant in sustainableagriculture because they improve the yield and quality of lettuce by increasing the bioactive compounds.

关键词： Biostimulant bioactive compounds enzymatic activity

Rock mass structural recognition from drill monitoring technology in underground mining using discontinuity index and machine learning techniques

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2023年第5期33卷 555-571页

作者： Alberto Fernández JoséA.Sanchidrián pablo Segarra Santiago gómez Enming Li Rafael Navarro Universidad Politécnica de Madrid–ETSI Minas y Energía Spain Universidad de Salamanca–gIR Charrock Spain

A procedure to recognize individual discontinuities in rock mass from measurement while drilling(MWD)technology is developed,using the binary pattern of structural rock characteristics obtained from in-hole images for *** from two underground operations with different drilling technology and different rock mass characteristics are considered,which generalizes the application of the methodology to different sites and ensures the full operational integration of MWD data *** approaches are followed for site-specific structural model building:a discontinuity index(DI)built from variations in MWD parameters,and a machine learning(ML)classifier as function of the drilling parameters and their *** prediction ability of the models is quantitatively assessed as the rate of recognition of discontinuities observed in borehole *** between the parameters involved in the models for each site,and differences in their weights,highlight the site-dependence of the resulting *** ML approach offers better performance than the classical DI,with recognition rates in the range 89%to 96%.However,the simpler DI still yields fairly accurate results,with recognition rates 70%to 90%.These results validate the adaptive MWD-based methodology as an engineering solution to predict rock structural condition in underground mining operations.

关键词： Drill monitoring technology Rock mass characterization Underground mining Similarity metrics of binary vectors Structural rock factor Machine learning

Vinyl sulfonyl chemistry-driven unidirectional transport of a macrocycle through a[2]rotaxane

在线全文

学校读者我要写书评

暂无评论

Organic Chemistry Frontiers 2022年第3期9卷 633-642页

作者： Arthur H.g.David pablo garcía-Cerezo Araceli g.Campaña Francisco Santoyo-gonzález Victor Blanco Departamento de Química Orgánica Facultad de CienciasUnidad de Excelencia de Química Aplicada a Biomedicina y Medioambiente(UEQ)Universidad de Granada(UGR)Avda.Fuente Nueva S/N18071 GranadaSpain

By applying a combination of the coupling-and-decoupling(CAD)chemistry of the vinyl sulfonate group with the click thia-Michael addition to the vinyl sulfone group(MAVS)we performed the irreversible unidirectional transportation of the ring through the linear component in a[2]rotaxane by a chemically and pHdriven flashing energy ratchet mechanism.

关键词： mechanism unidirectional chemistry