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Daily Physical Activity Improves Vascular Function and Motor Skills in Children

Journal of Sports Science 2017年第2期5卷 78-88页

作者： sascha ketelhut Kerstin ketelhut Claudia Hacke Reinhard Günter ketelhut Charité-University Medicine Berlin Berlin 10117 Germany Institute of Sports Science Martin-Luther-University Halle-Wittenberg Halle (Saale) 06120 Germany Medical School Berlin Berlin 12247 Germany Institute of Medical Biometry and Epidemiology University Medical Centre Hamburg-Eppendorf Hamburg 20251 Germany Medical Center Berlin (MCB) Berlin 10559 Germany Institute of Sports Medicine Humboldt-University Berlin Berlin 10115 Germany

The literature is consistent that regular physical activity in children has to be increased in order to compensate the negative health effects resulting from growing sedentary lifestyle. Thus, we analyzed in 45 students （aged 6.6 ± 0.7 years） the effects of a regular exercise intervention, on top of the normal physical education classes, on motor performance （MP） and hemodynamic parameters. The students were randomized either to an intervention （INT）（n = 23） or a control （CON）（n = 22） group. Throughout a 9 months period, INT received additional exercise interventions two days a week for 45 minutes. The main outcome measures were MP, peripheral and central blood pressure （BP）, augmentation index （Alx） and aortic pulse wave velocity （aPWV）. After the exercise intervention, we found significant （P 〈 0.05） positive effects on various test items of MP and significant decreases in peripheral and central systolic BP in INT. In contrast, in CON the respective parameters increased in CON alter the observation period. Moreover, aPWV decreased significantly in INT （P = 0.047） and increased in CON, thus resulting in a significant difference in the mean change （P = 0.043）. There were no considerable changes in AIx in both groups. In conclusion, we demonstrated that an increase in regular physical activity has a positive influence on development of MP and hemodynamic parameters even in early childhood. The findings of this study suggest that an increase in exercise time should be initiated as early as possible to improve motor ability and prevent future cardiovascular risk.

关键词： Physical fitness in children exercise and blood pressure arterial stiffness motor performance.

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Metric Expansion from Microscopic Dynamics in an Inhomogeneous Universe

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Communications in Theoretical Physics 2010年第9期54卷 477-483页

作者： sascha Vongehr Department of Philosophy Nanjing University National Key Laboratory of Solid-State Microstructures Department of Materials Science and EngineeringNanjing University

Theories with ingredients like the Higgs mechanism, gravitons, and inflaton fields rejuvenate the idea that relativistic kinematics is dynamically emergent. Eternal inflation treats the Hubble constant H as depending on location. Microscopic dynamics implies that H is over much smaller lengths than pocket universes to be understood as a local space reproduction rate. We illustrate this via discussing that even exponential inflation in TeV-gravity is slow on the relevant time scale. In our on small scales inhomogeneous cosmos, a reproduction rate H depends on position. We therefore discuss Einstein-Strauss vacuoles and a Lindquist-Wheeler like lattice to connect the local rate properly with the scaling of an expanding cosmos. Consistency allows H to locally depend on Weyl curvature similar to vacuum polarization. We derive a proportionality constant known from Kepler＇s third law and discuss the implications for the finiteness of the cosmological constant.

关键词： general relativity metric expansion black hole infinite Lindquist-Wheeler lattice

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Adapting Nanotech Research as Nano-Micro Hybrids Approach Biological Complexity,A Review

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Journal of Materials Science & Technology 2016年第5期32卷 387-401页

作者： sascha Vongehr Shaochun Tang Xiangkang Meng Institute of Materials Engineering National Laboratory of Solid State Microstructures College of Engineering and Applied Sciences Nanjing University

Today＇s emergence of nano-micro hybrid structures with almost biological complexity is of fundamental interest. Our ability to adapt intelligently to the challenges has ramifications all the way from fundamentally changing research itself, over applications critical to future survival, to posing globally existential dangers. Touching on specific issues such as how complexity relates to the catalytic prowess of multi-metal compounds, we discuss the increasingly urgent issues in nanotechnology also very generally and guided by the motto ＇Bio Is Nature＇s Nanotech＇. Technology belongs to macro-evolution; for example integration with artificial intelligence （AI） is inevitable. Darwinian adaptation manifests as integration of complexity, and awareness of this helps in developing adaptable research methods that can find use across a wide range of research. The second half of this work reviews a diverse range of projects which all benefited from ＇playful＇ programming aimed at dealing with complexity. The main purpose of reviewing them is to show how such projects benefit from and fit in with the general, philosophical approach, proving the relevance of the ＇big picture＇ where it is usually disregarded.

关键词： Complex hybrid structures Catalysis Macro-evolution Optimization Image analysis Simulation Statistical analysis Error analysis Critique of technology

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Influence of loading and heating processes on elastic and geomechanical properties of eclogites and granulites

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 127-137页

作者： Hem Bahadur Motra sascha Zertani Department of Geosciences Marine and Land Geomechanics and Geotechnics University of Kiel Institut für Geologische Wissenschaften Freie Universitat Berlin

Increased knowledge of the elastic and geomechnical properties of rocks is important for numerous engineering and geoscience applications(e.g. petroleum geoscience, underground waste repositories,geothermal energy, earthquake studies, and hydrocarbon exploration). To assess the effect of pressure and temperature on seismic velocities and their anisotropy, laboratory experiments were conducted on metamorphic rocks. P-(Vp) and S-wave(Vs) velocities were determined on cubic samples of granulites and eclogites with an edge length of 43 mm in a triaxial multianvil apparatus using the ultrasonic pulse emission technique in dependence of changes in pressure and temperature. At successive isotropic pressure states up to 600 MPa and temperatures up to 600 ℃, measurements were performed related to the sample coordinates given by the three principal fabric directions(x, y, z) representing the foliation(xy-plane), the normal to the foliation(z-direction), and the lineation direction(x-direction). Progressive volumetric strain was logged by the discrete piston displacements. Cumulative errors in Vpand Vsare estimated to be <1%. Microcrack closure significantly contributes to the increase in seismic velocities and decrease in anisotropies for pressures up to 200-250 MPa. Characteristic P-wave anisotropies of about 10% are obtained for eclogite and 3-4% in a strongly retrogressed eclogite as well as granulites. The wave velocities were used to calculate the geomechanical properties(e.g. density, Poisson’s ratio, volumetric strain, and elastic moduli) at different pressure and temperature conditions. These results contribute to the reliable estimate of geomechanical properties of rocks.

关键词： Anisotropy Elastic wave velocities Dynamic elastic moduli Geomechanical rock properties Microcrack

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Meta-analysis of probiotics for the treatment of irritable bowel syndrome

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World Journal of Gastroenterology 2008年第17期14卷 2650-2661页

作者： Lynne V McFarland sascha Dublin Department of Health Services Research and Development Group Health Center for Health Studies

Irritable bowel syndrome （IBS） is a chronic condition affecting 3%-25% of the general population. As no curative treatment is available, therapy is aimed at reducing symptoms, often with little success. Because alteration of the normal intestinal microflora has been observed in IBS, probiotics （beneficial microbes taken to improve health） may be useful in reducing symptoms. This paper systematically reviews randomized, controlled, blinded bials of probiotics for the treatment of IBS and synthesizes data on efficacy across trials of adequate quality. Pubr4ed, Medline, Google Scholar, NIH registry of clinical trials, metaRegister, and the Cochrane Central Register of Controlled Trials were searched from 1982-2007. We also conducted secondary searches of reference lists, reviews, commentaries, relevant articles on associated diseases, books and meeting abstracts. Twenty trials with 23 probiotic treatment arms and a total of 1404 subjects met inclusion criteria. Probiotic use was associated with improvement in global IBS symptoms compared to placebo [pooled relative risk （RRpooled） 0.77, 95% confidence interval （95% CI） 0.62-0.94]. Probiotics were also associated with less abdominal pain compared to placebo [RRpooled = 0.78 （0.69-0.88）]. Too few studies reported data on other IBS symptoms or on specific probiotic strains to allow estimation of a pooled RR. While our analyses suggest that probiotic use may be associated with improvement in IBS symptoms compared to placebo, these results should be interpreted with caution, given the methodological limitations of contributing studies. Probiotics warrant further study as a potential therapy for IBS.

关键词： Probiotics Meta-analysis Irritable bowel syndrome

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Investigation of the heat distribution in dry friction systems during fade and recovery using fiber-optic sensing and infrared technology

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Friction 2022年第3期10卷 422-435页

作者： Albert ALBERS Thomas KLOTZ Chris FINK sascha OTT IPEK–Institute of Product Engineering Karlsruhe Institute of TechnologyBaden Wurttemberg 76131Germany

The design of dry-running friction pairings and systems determines not only their installation space and costs,but also their reliability under critical load conditions,for example in emergencies,in the case of faults,and in the event of *** knowledge of the contact pattern is highly important for the development of clutches and brakes,the contact-related measurement of the temperature of these systems has not yet been solved in a satisfactory *** its importance,the temperature distribution has only been measured in a few ***,temperature measurements of complete clutches and brakes are carried out using thermocouples *** this study,a new innovative test setup is *** setup is able to measure the heat distribution of the lining and the steel disk of a brake with high spatial resolution by means of fiber optic sensing technology and *** a novelty,it enables measurement of the heat distribution and allows to correlate it with the fade and recovery *** to the expectations,the contact pattern is heterogeneous in circumferential *** causes are discussed using simulation *** with surface analysis,the new setup contributes to the investigation of the causes of fade and recovery.

关键词： dry-running clutch and brake fade and recovery high-resolution spatial temperature distribution measurement

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"Moonlighting" at the power plant: how mitochondria facilitate serial killing by CD8^(+) cytotoxic T cells

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Signal Transduction and Targeted Therapy 2022年第1期7卷 15-16页

作者： Dimitrios Mougiakakos sascha Kahlfuss Department of Hematology Oncologyand Stem Cell TransplantationOtto-von-Guericke University MagdeburgMagdeburgGermany Institute of Molecular and Clinical Immunology Medical FacultyOtto-von-Guericke University MagdeburgMagdeburgGermany Institute of Medical Microbiology and Hospital Hygiene Medical FacultyOtto-von-Guericke University MagdeburgMagdeburgGermany Health Campus Immunology InfectiologyInflammation(GC-I3)Medical FacultyOtto-von-Guericke UniversityMagdeburgGermany Center for Health and Medical Prevention(CHaMP) Otto-von-Guericke UniversityMagdeburgGermany

Griffiths and colleagues rece ntly dem on strated in Science^(1) that mitochondrial translation is required by CD8^(+)cytotoxic T cells(CTLs)to facilitate serial killing of target ***8^(+)CTLs provide immunity to viruses and tumors by acting as serial killers that eliminate infected or transformed target cells one after *** achieve that,CTLs utilize a cytotoxic protein machinery that involves perforin and granzymes to activate effector caspases and to induce apoptosis in target cells.

关键词： cytotoxic immunity lighting

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Simulating small-scale climate change effects-lessons from a short-term field manipulation experiment on grassland arthropods

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Insect Science 2013年第5期20卷 662-670页

作者： sascha Buchholz Dorothee Rolfsmeyer Jens Schirmel Department of Ecology TU Berlin Institute of Landscape Ecology University of Munster Robert-Koch-Straβe 26 48149 Munster Ecosystem Analysis University ofKoblenz-Landau Fortstraβe 7 76829 Landau Germany

Climate change is expected to cause major consequences on biodiversity. Understanding species-specific reactions, such as species shifts, species declines, and changes in population dynamics is a key issue to quantify large-scale impacts of climate change on biotic communities. As it is often impossible or at least impracticable to conduct large-scale experiments on biotic responses to climate change, studies at a smaller scale may be a useful alternative. In our study, we therefore tested responses of grassland arthropods （carabid beetles, spiders, grasshoppers） to simulated climate change in terms of species activity densities and diversity. We conducted a controlled field experiment by changing water and microclimatic conditions at a small scale （16 m2）. Roof constructions were used to increase drought-like conditions, whereas water supply was enhanced by irrigation. In all, 2 038 carabid beetles （36 species）, 4 893 spiders （65 species）, and 303 Orthoptera （4 species） were caught using pitfall traps from May to August, 2010. During our experiment, we created an artificial small-scale climate change; and statistics revealed that these changes had short-term effects on the total number of individuals and Simpson diversity of the studied arthropod groups. Moreover, our results showed that certain species might react very quickly to climate change in terms of activity densities, which in turn might influence diversity due to shifts in abundance patterns. Finally, we devised methodological improvements that may further enhance the validity of future studies.

关键词： carabid beetles drought global wanning grasshoppers irrigation spiders

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Collision statistics of clusters:from Poisson model to Poisson mixtures

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Chinese Physics B 2010年第2期19卷 225-233页

作者： sascha Vongehr 唐少春孟祥康 National Laboratory of Solid State Microstructures Department of Materials Science and EngineeringNanjing University

Clusters traverse a gas and collide with gas particles. The gas particles are absorbed, and the clusters become hosts. If the clusters are size-selected, the number of guests will be Poisson distributed. We review this by showcasing four laboratory procedures that all rely on the validity of the Poisson model. The effects of a statistical distribution of the clusters＇ sizes in a beam of clusters are discussed. We derive the average collision rates. Additionally, we present Poisson mixture models that also involve standard deviations. We derive the collision statistics for common size distributions of hosts and also for some generalizations thereof. The models can be applied to large noble gas clusters traversing doping gas. While outlining how to fit a generalized Poisson to the statistics, we still find even these Poisson models to be often insufficient.

关键词： collision statistics helium droplets clusters Poisson statistics

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Asymmetric cytokinin signaling opposes gravitropism in roots^∞

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Journal of Integrative Plant Biology 2020年第7期62卷 882-886页

作者： sascha Waidmann Jürgen Kleine-Vehn Department of Applied Genetics and Cell Biology University of Natural Resources and Life Sciences(BOKU)Muthgasse 18Vienna1190Austria

In contrast to primary roots,lateral roots partially repress gravitropic growth and establish a distinct gravitropic set point angle(GSA;Digby and Firn 1995).The distinct GSAs of primary and lateral roots ultimately allow the root system to radially explore its surroundings(Mullen and Hangarter 2003).Lateral roots emerge in a 90°angle from the primary root(so-called stage I;Figure 1).

关键词： roots Figure

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