检索结果-南通市图书馆

Time-resolved impact electrochemistry for quantitative measurement of single-nanoparticle reaction kinetics

在线全文

学校读者我要写书评

暂无评论

Nano Research 2017年第11期10卷 3680-3689页

作者： En Ning Saw markus kratz kristina Tschulik Micro-&Nano-Electrochemistry and Centre for Electrochemical Sciences(CES) Ruhr-University BochumBochum D-44780Germany

Single-nanoparticle electrochemistry has been established as a tool to characterize various nanomaterials based on the charge passed during their random impact at an *** it is demonstrated that the duration and shape of the resulting current peak can be used to quantify the reaction kinetics on a single-particle *** the chemical rate constant and reaction mechanism for oxidation of single nanoparticles in different electrolytes can be determined directly from the duration of the current signal recorded in high-speed,high-sensitivity current *** 29-nm-sized Ag particles in four different electrolytes as a proof of concept for this general approach,hitherto inaccessible insights into single-particle reactivity are *** comparable rate constants were measured for the four electrolytes at low overpotentials,transport-limited impacts at high overpotentials were found to depend strongly on the type and quantity of anions present in solution.

关键词： single-particle reactivity electrochemical kinetics nano-impact method silver reaction mechanism

Focal Points at Infinity for Short-Range Scattering Trajectories

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Shanghai Jiaotong university(Science) 2018年第1期23卷 146-157页

作者： HOHBERGER Horst kLEIN markus University of Michigan-Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong University Institute for Mathematics University of Potsdam

Classical scattering trajectories are known to form a Lagrangian manifold in euclidean phase space,which allows the classification of local focal points for sufficiently small dimensions. For the case of a short-range potential, we show that the natural description of focal points at infinity is a Lagrangian manifold in the cotangent bundle of the sphere and establish the relationship between focal points at infinity and the projection singularities of that manifold.

关键词： Lagrangian manifold classical scattering theory short-range potential

Soil functional indicators in mixed beech forests are clearly species-specifi c

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2023年第4期34卷 1033-1049页

作者： Yahya kooch Neda Ghorbanzadeh Samaneh Hajimirzaaghaee markus Egli Faculty of Natural Resources&Marine Sciences Tarbiat Modares UniversityNoor 46417-76489MazandaranIran Faculty of Natural Resources University of GuilanSowmeh Sara 4432-3136GuilanIran Faculty of Natural Resources University of Agricultural Sciences and Natural ResourcesSariIran Department of Geography University of ZürichZurichSwitzerland

Beech stands are considered part of the ancient forest ecosystems in the northern *** mixed stands in beach forest ecosystems,the type of associated tree species can signifi cantly aff ect soil functions,but their infl uence on microbial activity,nutrient cycling and belowground properties is ***,we considered forest patches in northern Iran that are dominated by diff erent tree species:Fagus orientalis Lipsky,Quercus castaneifolia ***.,Pterocarya fraxinifolia(Lam.),Tilia begonifolia Stev.,Zelkova carpinifolia Dippe,Acer cappadocicum Gled,Acer velutinum Boiss.,Fraxinus excelsior L.,Carpinus betulus L.,and Alnus subcordata *** each forest patch–tree species,litter and soil samples(25×25×10 cm,100 of each)were analyzed for determine soil and litter properties and their relationship with tree *** litter decomposition rate during a 1-year experiment was also determined.A PCA showed a clear diff erence between selected litter and soil characteristics among tree ***,***,***,***,***,***,and *** enhanced soil microbial biomass of carbon,whereas patches with ***,*** and *** had faster litter decomposition and enhanced biotic activities and C and N ***,soil function indicators were species-specifi c in the mixed beech ***(a N-fi xing species),*** and *** were main drivers of microbial activities related to nutrient cycling in the old-growth beech forest.

关键词： Old-growth forest Deciduous tree species Soil fertility Microbial activities Carbon and nitrogen cycle

Helicobacter pylori vaccination:Is there a path to protection?

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2014年第34期20卷 11939-11949页

作者： Florian Anderl markus Gerhard Institute for Medical Microbiology Immunology and HygieneTechnische Universit?t MünchenMunich 81675Germany

Helicobacter pylori (H. pylori) is a pathogenic, extracellular bacterium that colonizes the stomach in approximately 50% of the world population. It strongly interacts with the gastric epithelium and mostly causes asymptomatic gastritis. The colonization of H. pylori leads to ulcer development in around 20% of infected patients and may progress to gastric cancer or mucosa-associated lymphoid tissue lymphoma in 1%. Thus, H. pylori is the major cause of gastric cancer worldwide. It has been classified as a class I carcinogen by the World Health Organization. Since its discovery in the early eighties by Warren and Marshall, research has been focused on the investigation of H. pylori biology, host-pathogen interaction, prevention and treatment. Although H. pylori induces a strong humoral and local cellular immune response, the pathogen is not cleared and establishes a chronic infection after encounters in childhood. The ability to colonize the stomach is mediated by several virulence factors that change the host environment, promote adhesion to the epithelium, influence the gastric inflammation and induce immune evasion. H. pylori can be eradicated by antibiotic treatment in combination with a proton-pump inhibitor, but efficacy is decreasing. Current therapies are expensive, have side effects and contribute to increasing antibiotic resistance, underlining the need for novel therapeutics.

关键词： Helicobacter pylori Vaccination Immune response Dendritic cells T-cells

Structural integrity and remodeling underlying functional recovery after stroke

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2021年第7期16卷 1423-1424页

作者： Frederique Wieters markus Aswendt University of Cologne Faculty of Medicine and University Hospital CologneDepartment of NeurologyCologneGermany Cognitive Neuroscience Institute of Neuroscience and Medicine(INM-3)Research Center JuelichGermany

Stroke is the second leading cause of death worldwide with about 50% of survivors being chronically disabled(Donkor,2018).The behavioral improvement seen in stroke patients in the first weeks after a stroke is contributed by behavioral compensation, reorganization in somatotopic maps and activity in peri-infarct but also distant regions which are connected to the stroke area as supported by animal studies.

关键词： remodeling death after

Soil conditions and phylogenetic relatedness influence total community trait space during early plant succession

在线全文

学校读者我要写书评

暂无评论

Journal of Plant Ecology 2014年第4期7卷 321-329页

作者： Werner Ulrich Marcin Piwczyński markus k.Zaplata Susanne Winter Wolfgang Schaaf Anton Fischer Nicolaus Copernicus University in Torun Lwowska 1PL 87-100 ToruńPoland Center Landscape Development and Mining Landscapes(FZLB) Brandenburg University of Technology Cottbus-SenftenbergKonrad-Wachsmann-Allee 6D-03046 CottbusGermany Center of Life and Food Sciences Technische Universität MünchenEmil-Ramann-Straße 6D-85354 FreisingGermany Technische Universität Dresden Pienner Straße 8D-01737 TharandtGermany Brandenburg University of Technology Cottbus Konrad-Wachsmann-Allee 6D-03046 Cottbus-SenftenbergGermanyl Center of Life and Food Sciences Technische Universität MünchenHans-Carl-von-Carlowitz-Platz 2D-85354 FreisingGermany

Aims the total space of traits covered by the members of plant com-munities is an important parameter of ecosystem functioning and *** trace the variability of trait space during early plant succession and ask how trait space co-varies with phylogenetic community structure and soil ***,we are inter-ested in the small-scale variability in trait space and the influence of biotic and abiotic *** We use data on species richness and soil conditions from the first 7 years of initial succession of an artificial catchment in north-east-ern *** functional attribute diversity serves as a proxy to total trait *** Findingstotal trait space steadily increased during *** observed high small-scale variability in total trait space that was positively correlated with species richness and phylogenetic segregation and negatively correlated with total plant *** space increased with soil carbonate content,while pH and the fraction of sandy material behaved *** results indicate that during early succession,habitat filtering processes gain importance leading to a lesser increase in trait space than expected from the increase in species richness alone.

关键词： primary succession trait space phylogenetic signal habitat filtering species co-occurrence null model

kAI1 gene is differently expressed in papillary and pancreatic cancer:influence on metastasis

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 2000年第6期6卷 866-871页

作者： Helmut Friess markus W.Buchler Department of Visceral and Transplantation Surgery University of BernInselspitalBernSwitzerland

AIM To compare kAI1 in cancer of papilla ofVater and pancreas to evaluate whether there aredifferences in biologic behavior which mightaccount for *** We compared the expression in 24papillay and 29 pancreatic cancers usingNorthern blot analysis,immunochemical assayand in situ hybridization,and investigatedwhether early diagnosis or molecular differencespredict the outcome in these tumor *** By Northern blot analysis there is nostatistical difference of kAI1 levels in normaland cancerous *** association betweenkAI1 mRNA expression and tumor stage or tumordifferentiation was found in the *** assay,kAI1 staining incytoplasm of papillary cancer cells was similarto that of normal papillary *** in situhybridization,the results of kAI1 mRNAexpression in normal and cancerous papilla weresimilar to those with *** normal and cancerous pancreastissues were also analyzed by the methods usedin papillary *** Although the biologic roles of kAI1 have not been clarified, our results suggest that kAI1 may restrict the progression of malignant papillary cancer, but its expression might not have any effect on the characteristics of papillary tumor, whereas by the analysis of kAl1 gene, its reduced expression is closely related to the progression and metastases of pancreatic cancer.

关键词： pancreatic neoplasms papillary neoplasms kAI1 gene immunohistochemistry in situ hybridization blotting northern

A revised Mississippian lithostratigraphy of County Galway(western Ireland) with an analysis of carbonate lithofacies, biostratigraphy, depositional environments and palaeogeographic reconstructions utilising new borehole data

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2015年第1期4卷 1-26页

作者： markus Pracht Ian D.Somerville Geological Survey of Ireland Beggars Bush Dublin 4 Ireland UCD School of Geological Sciences University College DublinBelfield Dublin 4 Ireland

An integrated study of borehole data and outcrop of Mississippian （late Tournaisian to late Visean） rocks in Co. （County） Galway, western Ireland has enabled a more detailed geological map and lithostratigraphy to be constructed for the region. Several carbonate formations have been distinguished by microfacies analysis and their precise ages established by micropalaeontological investigations using foraminifers and calcareous algae. In addition, palaeogeographic maps have been constructed for the late Tournaisian, and early to late Visoan intervals in the region. The oldest marine Mississippian （late Tournaisian） deposits are recorded in the south of the study region from the Loughrea/Tynagh area and further south in the Gort Borehole; they belong to the Limerick Province. They comprise the Lower Limestone Shale Group succeeded by the Ballysteen Group, Waulsortian Limestone and kilbryan Limestone Formations. These rocks were deposited in increasing water depth associated with a transgression that moved northwards across Co. Galway. In the northwest and north of the region, marginal marine and non-marine Tournaisian rocks are developed, with a shoreline located NW of Galway City （Galway High）. The central region of Co. Galway has a standard Visdan marine succession that can be directly correlated with the Carrick-on- Shannon succession in counties Leitrim and Roscommon to the northeast and east as far as the River Shannon. It is dominated by shallow-water limestones （Oakport, Ballymore and Croghan Limestone Formations） that formed the Galway-Roscommon Shelf. This facies is lat- erally equivalent to the Tubber Formation to the south which developed on the Clare-Galway Shelf. In the southeast, basinal facies of the Lucan Formation accumulated in the Athenry Basin throughout much of the Visean. This basin formed during a phase of extensional tectonics in the early Visean and was probably connected to the Tynagh Basin to the east. In the late Visean, shallow-water limes

关键词： Carboniferous Mississippian western Ireland carbonate microfaciesbiostratigraphy foraminifers shelf and basin environments palaeogeography

In vivo bioluminescence imaging to elucidate stem cell graft differentiation

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2020年第1期15卷 61-62页

作者： Stefanie Vogel Mathias Hoehn markus Aswendt Technische Universitat Dresden DFG-Research Center for Regenerative Therapies Dresden(CRTD)DresdenGermany Cognitive Neuroscience Institute of Neuroscience and Medicine(INM-3)Research Center JuelichJuelichGermany Leiden University Medical Center Department of RadiologyLeidenThe Netherlands University of Cologne Faculty of Medicine and University Hospital CologneDepartment of NeurologyCologneGermany

Neurological disorders including neurodegeneration(e.g.,Alzheimer’s disease and Parkinson’s disease)and acute injuries(e.g.,stroke and traumatic brain injury)are the leading cause group of disability-adjusted life years and the second leading cause group of *** to other tissues,the adult brain retains only a very limited repair *** neurogenesis,the lifelong generation of new neurons,declines with age and in degenerative diseases,such as Alzheimer’s ***,independently of age,the proliferation and migration of endogenous stem cells is stimulated after brain injuries and might be related to recovery processes(Adamczak et al.,2017).The limited number of endogenous stem cells during adulthood is one of the major limitations for an efficient regeneration of the injury affected brain ***,the transplantation of neural stem or progenitor cells(NSCs/NPCs)is extensively studied in mouse models and applied in first clinical trials with the aim to replace dysfunctional or lost neural cells and thus to restore brain function.

关键词： injuries endogenous replace