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World Journal of Gastroenterology 2020年第3期26卷 279-290页

作者： matthias Ocker Department of Gastroenterology(CBF) Charité University Medicine Berlin

Metabolic disorders are increasingly leading to non-alcoholic fatty liver disease,subsequent steatohepatitis,cirrhosis and hepatocellular *** growth factors and their receptors play an important role in maintaining metabolic homeostasis also in the liver and disorders in signaling have been identified to contribute to those pathophysiologic conditions leading to hepatic lipid accumulation and chronic *** specific and well tolerated inhibitors of fibroblast growth factor receptor activity are currently developed for(non-liver)cancer therapy,treatment of non-alcoholic fatty liver disease and nonalcoholic steatohepatitis is still *** growth factor-mimicking or restoring approaches have recently evolved as a novel therapeutic option and the impact of such interactions with the fibroblast growth factor receptor signaling network during non-alcoholic fatty liver disease/non-alcoholic steatohepatitis development is reviewed here.

关键词： Fibroblast growth factor Fibroblast growth factor receptor Non-alcoholic fatty liver disease Non-alcoholic steatohepatitis Fibrosis Cirrhosis Hepatocellular carcinoma

A Solution for the Flow Between a Cone and a Plate at Low Reynolds Number

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Journal of Thermal Science 2002年第4期11卷 289-295页

作者： matthias H.Buschmann Institute of Fluid Mechanics Dresden University of Technology

An analysis of the flow in the gap between a rotating cone and a stationary plate at low Reynolds numbers is presented. Using series expansions for the components of the mean velocity profile and the pressure gradient the Navier-Stokes equations and the continuity equation for a Newtonian fluid written in cylindrical coordinates are solved. It is found that the solution is stable and convergent for the local Reynolds numbers Re smaller than 1.2928. The computed angle of the wall streamlines is found to be in good agreement with experimental data.

关键词： cone-plate-apparatus three-dimensional laminar flow asymptotic expansion.

Incorporating shape constraints in generalized additive modelling of the height-diameter relationship for Norway spruce

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Forest Ecosystems 2016年第2期3卷 112-125页

作者： Natalya Pya matthias Schmidt Department of Mathematics School of Science and TechnologyNazarbayev University The Northwest German Forest Research Station Department of Forest Growth

Background： Measurements of tree heights and diameters are essential in forest assessment and modelling. Tree heights are used for estimating timber volume, site index and other important variables related to forest growth and yield, succession and carbon budget models. However, the diameter at breast height （dbh） can be more accurately obtained and at lower cost, than total tree height. Hence, generalized height-diameter （h-d） models that predict tree height from dbh, age and other covariates are needed. For a more flexible but biologically plausible estimation of covariate effects we use shape constrained generalized additive models as an extension of existing h-d model approaches. We use causal site parameters such as index of aridity to enhance the generality and causality of the models and to enable predictions under projected changeable climatic conditions. Methods： We develop unconstrained generalized additive models （GAM） and shape constrained generalized additive models （SCAM） for investigating the possible effects of tree-specific parameters such as tree age, relative diameter at breast height, and site-specific parameters such as index of aridity and sum of daily mean temperature during vegetation period, on the h-d relationship of forests in Lower Saxony, Germany. Results： Some of the derived effects, e.g. effects of age, index of aridity and sum of daily mean temperature have significantly non-linear pattern. The need for using SCAM results from the fact that some of the model effects show partially implausible patterns especially at the boundaries of data ranges. The derived model predicts monotonically increasing levels of tree height with increasing age and temperature sum and decreasing aridity and social rank of a tree within a stand, The definition of constraints leads only to marginal or minor decline in the model statistics like AIC An observed structured spatial trend in tree height is modelled via 2-dimensional surface fitting. Conclusions： We

关键词： Height-diameter curve Norway spruce Shape constrained additive models Impact of climate change,Varying coefficient models

Review on Dating Methods:Numerical Dating in the Quaternary Geology of High Asia

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Journal of Mountain Science 2010年第2期7卷 105-122页

作者： matthias Kuhle Sabine Kuhle Georg-August-University of Goettingen Department of Geography and High Mountain Geomorphology

Over the past few years, OSL and TCN datings of glacial material from High Asia have come into fashion. To this day, however, these techniques do not permit safe calibration. The intensity of the cosmic ray flux is being modulated by the solar and terrestrial magnetic fields and their secular fluctuations in the past. So far, these variations cannot be converted into the respective local TCN production rates for High Asia. We have reason to believe that the ages that are being calculated despite these uneertainties are generally overestimated. This assessment is supported by eonventional radiocarbon dates and above＂ all by the glacial chronology developed independently on the basis of the Quaternary geological method. The strongly emerging evidence for a much more extensive LGM glaciation of High Asia is, however, either being ignored or rejected by many authors, solely on the basis of the above-mentioned uncalibrated datings. This self-conceit based on the ＂dating fallacy＂, as we call it, should be avoided since it goes decidedly against the standards of the scientific method established in Quaternary geology and makes a fundamental scientific discussion impossible.

关键词： Calibration of numerical dating Geomagnetic field excursions Solar activity Interface problem Tibetan ice sheet Dating fallacy

Addressing administrative units in international tsunami early warning systems: shortcomings in international geocode standards

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International Journal of Digital Earth 2012年第4期5卷 356-371页

作者： matthias Lendholt Martin Hammitzsch German Research Centre for Geosciences Centre for GeoInformation TechnologyPotsdamGermany

Administrative units reflect the territorial hierarchies established within all countries of the *** units are addressable with geocodes that provide a bijective mapping between territories and unique identification *** warning systems for natural or man-made hazards often map affected or threatened areas to administrative units to establish a spatial reference that is comprehensible to all parts of the *** these territories in an international context has several requirements,such as worldwide coverage,completeness and topicality,which must be met by geocode *** this paper,the practicability and suitability of international geocode standards are examined in the context of the requirements of large-scale early warning *** paper exposes the insufficiencies and limitations of existing geocode standards International Organization for Standardization(ISO)-3166,Second Administrative Level Boundaries data set project(SALB)and Nomenclature of the Territorial Units for Statistics(NUTS)and emphasises the suitability of the non-official hierarchical administrative subdivision codes(HASC).The analysis is framed in the context of addressing affected areas for an Indian Ocean tsunami early warning *** system was developed within the Distant Early Warning Systems project according to the requirements of the United Nations Educational,Scientific and Cultural Organization(UNESCO)Intergovernmental Oceanic Commission for Regional Tsunami Watch Providers(RTWPs).

关键词： digital earth early warning system spatial reference geocode SALB HASC ISO-3166

Gut hormones, and short bowel syndrome: The enigmatic role of glucagon-like peptide-2 in the regulation of intestinal adaptation

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World Journal of Gastroenterology 2006年第26期12卷 4117-4129页

作者： gr Martin PL Beck DL Sigalet University of Calgary Gastrointestinal Research group CalgaryAlberta T2N 4N1Canada

Short bowel syndrome （SBS） refers to the malabsorption of nutrients, water, and essential vitamins as a result of disease or surgical removal of parts of the small intestine. The most common reasons for removing part of the small intestine are due to surgical intervention for the treatment of either Crohn＇s disease or necrotizing enterocolitis. Intestinal adaptation following resection may take weeks to months to be achieved, thus nutritional support requires a variety of therapeutic measures, which include parenteral nutrition. Improper nutrition management can leave the SBS patient malnourished and/or dehydrated, which can be life threatening. The development of therapeutic strategies that reduce both the complications and medical costs associated with SBS/long-term parenteral nutrition while enhancing the intestinal adaptive response would be valuable. Currently, therapeutic options available for the treatment of SBS are limited. There are many potential stimulators of intestinal adaptation including peptide hormones, growth factors, and neuronally-derived components. Glucagon-like peptide-2 （GLP-2） is one potential treatment for gastrointestinal disorders associated with insufficient mucosal function. A significant body of evidence demonstrates that GLP-2 is atrophic hormone that plays an important role in controlling intestinal adaptation. Recent data from clinical trials demonstrate that GLP-2 is safe, well-tolerated, and promotes intestinal growth in SBS patients. However, the mechanism of action and the localization of the glucagon-like peptide-2 receptor （GLP-2R） remains an enigma. This review summarizes the role of a number of mucosal-derived factors that might be involved with intestinal adaptation processes; however, this discussion primarily examines the physiology, mechanism of action, and utility of GLP-2 in the regulation of intestinal mucosal growth.

关键词： Short bowel syndrome Glucagon-likepeptide-2 Epidermal growth factor Insulin-like growthfactor-I Parenteral nutrition Total parenteral nutrition Intestinal adaptation Intestinal mucosa Gut hormones Enteric nervous system

Assessing risks and uncertainties in forest dynamics under different management scenarios and climate change

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Forest Ecosystems 2015年第3期2卷 169-189页

作者： matthias Albert Jan Hansen Jürgen Nagel matthias Schmidt Hermann Spellmann Northwest German Forest Research Station

Background: Forest management faces a climate induced shift in growth potential and increasing current and emerging new risks. Vulnerability analysis provides decision support based on projections of natural resources taking risks and uncertainties into account. In this paper we(1) characterize differences in forest dynamics under three management scenarios,(2) analyse the effects of the three scenarios on two risk factors, windthrow and drought stress, and(3) quantify the effects and the amount of uncertainty arising from climate projections on height increment and drought ***: In four regions in northern Germany, we apply three contrasting management scenarios and project forest development under climate change until 2070. Three climate runs(minimum, median, maximum) based on the emission scenario RCP 8.5 control the site-sensitive forest growth functions. The minimum and maximum climate run define the range of prospective climate ***: The projections of different management regimes until 2070 show the diverging medium-term effects of thinnings and harvests and long-term effects of species conversion on a regional scale. Examples of windthrow vulnerability and drought stress reveal how adaptation measures depend on the applied management path and the decision-maker’s risk attitude. Uncertainty analysis shows the increasing variability of drought risk projections with time. The effect of climate projections on height growth are quantified and uncertainty analysis reveals that height growth of young trees is dominated by the age-trend whereas the climate signal in height increment of older trees is ***: Drought risk is a serious issue in the eastern regions independent of the applied silvicultural scenario,but adaptation measures are limited as the proportion of the most drought tolerant species Scots pine is already high. Windthrow risk is no serious overall threat in any region, but adequate counter-measures such as spec

关键词： Climate change Silvicultural management strategies

Analysis of drop deformation dynamics in turbulent flow

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Chinese Journal of Chemical Engineering 2016年第2期24卷 264-277页

作者： Stephanie Nachtigall Daniel Zedel matthias Kraume Chair of Chemical and Process Engineering Technische Universitat Berlin

Drop breakage and coalescence influence the particle formation in liquid-liquid dispersions. In order to reduce the influencing factors of the whole dispersion process, single drops where coalescence processes can be neglected were analyzed in this work. Drops passing the turbulent vicinity of a single stirrer blade were investi- gated by high-speed imaging. In order to gain a statistically relevant amount of drops passing the area of interest and corresponding breakage events, at least 1600 droplets were considered for each parameter set of this work. A specially developed fully automatic image analysis based on Matlab was used for the evaluation of the resulting high amount of image data. This allowed the elimination of the time-consuming manual analysis and further- more, allowed the objective evaluation of the drops＇ behavior. Different deformation parameters were consid- ered in order to describe the drop deformation dynamics properly. Regarding the ratio of both main particle axes （0axes）, which was therefore approximated through an ellipse, allowed the determination of very small de- viations from the spherical shape. The perimeter of the particle （0peri） was used for the description of highly de- formed shapes. In this work the results of a higher viscosity paraffin oil （ηd =127 mPa. s） and a low viscosity solvent （petroleum, ηd = 1.7 mPa-s） are presented with and without the addition of SDS to the continuous water phase. All results show that the experimentally determined oscillation but also deformation times underlie a wide spreading. Drop deformations significantly increased not only with increasing droplet viscosity, but also with decreasing interfacial tension. Highly deformed particles of one droplet species were more likely to break than more or less spherical particles. As droplet fragmentation results from a variety of different macro-scale de- formed particles, it is not assumed that a critical deformation value must be reached for the fragmentati

关键词： Drop deformation Drop breakage Liquid-liquid system Turbulent mixing Image analysis High-speed imaging

Chemical substances present in discharge water generated by laundry industry:Analytical monitoring

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Water Science and Engineering 2023年第4期16卷 324-332页

作者： Dario Lacalamita Chiara Mongioví grégorio Crini Chrono-environnement Laboratory University of Franche-Comté16 Route de GrayBesançon 25000France

To our knowledge,precise data concerning the pollution in terms of qualitative and quantitative fluctuations in discharge water from the laundry sector have seldom been *** study investigated the chemical composition of the discharge water from a laundry *** 160 chemical substances and 15 standard water parameters were *** results showed that the discharge water presented both inorganic and organic polycontamination with a high degree of qualitative and quantitative ***,of all monitored substances,only five metals(Al,Cu,Fe,Sr,and Zn),five minerals(P,Ca,K,Na,and S),and alkylphenols were systematically present and *** a daily average water flow of 129 m^(3),the released metal flux was 356 g/***,such as trichloromethane,brominated diphenyl ether(BDE)47,and fluorides,were occasionally found and *** substances,such as chlorophenols,organo-tins,and pesticides were never *** the samples had quantifiable levels in the chemical oxygen demand(COD),biological oxygen demand(BOD),and *** the concentrations of Zn(8.3 g/d),Cu(21.4 g/d),and BOD(57.4 g/d)were close to or above the regulatory values:74.0 g/d for Zn,9.0 g/d for Cu,and 57.0 kg/d for *** data obtained from this study are useful to the choice of additional treatments for the reduction of pollutant fluxes.

关键词： Laundry Discharge water Chemical analysis Water parameter Chemical substance

Smooth free-cycle dynamic soaring in unspecified shear wind via quadratic programming

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Chinese Journal of Aeronautics 2022年第7期35卷 19-29页

作者： Haichao HONG Benedikt grüTER Patrick PIPREK Florian HOLZAPFEL Institute of Flight System Dynamics Technical University of MunichGarching D-85748Germany

Harvesting wind energy is promising for extending long-endurance flights,which can be greatly facilitated by a flight technique called dynamic *** presented study is concerned with generating model-based trajectories with smooth control histories for dynamic soaring maneuvers exploiting wind *** desired smoothness is achieved by introducing a trigonometric series parameterization for the controls,which are formulated with respect to the normalized ***,the periodicity of the trigonometric functions is leveraged to facilitate the connection of cycles and streamline the problem *** relying on a specified wind profile,a freefinal-time quadratic programming-based control strategy is developed for the online correction of the flight trajectory,which requires only the instant wind *** and online numerical studies show the trade-off to achieve the smoothness and demonstrate the effectiveness of the proposed method in a varying wind field.

关键词： Dynamic soaring Optimal control Quadratic programming Trajectory generation Trigonometric series