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Wear dependent virtual flow rate sensor for progressing cavity pumps with deformable stator

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Petroleum Science 2024年第2期21卷 1346-1353页

作者： jens Müller Sebastian Leonow Johannes Schulz christian Hansen Martin Monnigmann Ruhr-Universitat Bochum Universit atsstraûe 150Bochum44801Germany SEEPEX GmbH Scharnh olzstraûe 344Bottrop46240Germany

This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this material loss on the volumetric efficiency. The results are combined with an established backflow model to implement a backflow calculation procedure that is adaptive to wear. We use a laboratory test setup with a highly abrasive fluid and operate a pump from new to worn condition to validate our approach. The obtained measurement data show that the presented virtual sensor is capable of calculating the flow rate of a pump being subject to wear during its regular operation.

关键词： Backflow Progressing cavity pump Virtual sensor Wear

Advanced brain organoids for neuroinflammation disease modeling

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Neural Regeneration Research 2024年第1期19卷 154-155页

作者： Sonia Sabate-Soler Henry Kurniawan jens christian Schwamborn Luxembourg Centre for Systems Biomedicine University of LuxembourgEsch-sur-AlzetteLuxembourg

Brain organoids mimic closely the embryonic human brain:Over the last decade,the development of human organoid systems has evolved *** tissues have been modeled with organoids,such as the gut,lung,liver,kidney retina and *** systems have a high cellular heterogeneity,with many cell types integrated into the same ***'cellular populations interact between and amongst each other in a cellular and molecular level,which represents an advantage with respects to monolayer 2D cell culture systems.

关键词： inflammation lung kidney

Influence of railway wheel tread damage on wheel-rail impact loads and the durability of wheelsets

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Railway Engineering Science 2024年第1期32卷 20-35页

作者： Michele Maglio Tore Vernersson jens C.O.nielsen Anders Ekberg Elena Kabo CHARMEC Department of Mechanical and Maritime SciencesChalmers University of TechnologySE‑41296 GothenburgSweden

Dynamic wheel-rail contact forces induced by a severe form of wheel tread damage have been measured by a wheel impact load detector during full-scale field tests at different vehicle *** on laser scanning,the measured three-dimensional damage geometry is employed in simulations of dynamic vehicle-track interaction to calibrate and verify a simulation *** relation between the magnitude of the impact load and various operational parameters,such as vehicle speed,lateral position of wheel-rail contact,track stiffness and position of impact within a sleeper bay,is *** calibrated model is later employed in simulations featuring other forms of tread damage;their effects on impact load and subsequent fatigue impact on bearings,wheel webs and subsurface initiated rolling contact fatigue of the wheel tread are *** results quantify the effects of wheel tread defects and are valuable in a shift towards condition-based maintenance of running gear,and for general assessment of the severity of different types of railway wheel tread damage.

关键词： Wheel tread damage Rolling contact fatigue cluster Field measurements Dynamic vehicle-track interaction Wheel-rail impact load Wheelset durability

Towards a standard diet-induced and biopsy-confirmed mouse model of non-alcoholic steatohepatitis: Impact of dietary fat source

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World Journal of Gastroenterology 2019年第33期25卷 4904-4920页

作者： Michelle L Boland Denise Oro Kirstine S T■lb■l Sebastian T Thrane jens christian nielsen Taylor S Cohen David E Tabor Fiona Fernandes Andrey Tovchigrechko Sanne S Veidal Paul Warrener Bret R Sellman Jacob Jelsing Michael Feigh Niels Vrang James L Trevaskis Henrik H Hansen Cardiovascular Renal and Metabolic DiseasesMedImmuneGaithersburgMD 20878United States Pharmacology GubraH■rsholm DK-2970Denmark

BACKGROUND The trans-fat containing AMLN(amylin liver non-alcoholic steatohepatitis,NASH)diet has been extensively validated in C57BL/6J mice with or without the Lep^ob/Lep^ob(ob/ob)mutation in the leptin gene for reliably inducing metabolic and liver histopathological changes recapitulating hallmarks of *** to a recent ban on trans-fats as food additive,there is a marked need for developing a new diet capable of promoting a compatible level of disease in ob/ob and C57BL/6J *** To develop a biopsy-confirmed mouse model of NASH based on an obesogenic diet with trans-fat substituted by saturated *** Male ob/ob mice were fed AMLN diet or a modified AMLN diet with trans-fat(Primex shortening)substituted by equivalent amounts of palm oil[Gubra amylin NASH,(GAN)diet]for 8,12 and 16 wk.C57BL/6J mice were fed the same diets for 28 *** and GAN diets had similar caloric content(40%fat kcal),fructose(22%)and cholesterol(2%)*** The GAN diet was more obesogenic compared to the AMLN diet and impaired glucose ***-confirmed steatosis,lobular inflammation,hepatocyte ballooning,fibrotic liver lesions and hepatic transcriptome changes were similar in ob/ob mice fed the GAN or AMLN diet.C57BL/6J mice developed a mild to moderate fibrotic NASH phenotype when fed the same *** Substitution of Primex with palm oil promotes a similar phenotype of biopsyconfirmed NASH in ob/ob and C57BL/6J mice,making GAN diet-induced obese mouse models suitable for characterizing novel NASH treatments.

关键词： Non-alcoholic steatohepatitis High-fat diet Mouse model Histopathology Fibrosis Liver biopsy Liver transcriptome

Small mammal community composition impacts bank vole (Clethrionomys glareolus) population dynamics and associated seroprevalence of Puumala orthohantavirus

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Integrative Zoology 2024年第1期19卷 52-65页

作者： Felicitas Maria BUJNOCH Daniela REIL Stephan DREWES Ulrike MROSENFELD Rainer G.ULRICH jens JACOB christian IMHOLT Julius Kühn-Institute Federal Research Centre for Cultivated PlantsInstitute for Epidemiology and Pathogen DiagnosticsRodent ResearchMünsterGermany University of Münster Institute for Evolution and BiodiversityMünsterGermany Friedrich-Loeffler-Institut Federal Research Institute for Animal HealthInstitute of Novel and Emerging Infectious DiseasesGreifswald-Insel RiemsGermany

Rodents are important reservoirs for zoonotic pathogens that cause diseases in *** is hypoth-esized to be closely related to pathogen prevalence through multiple direct and indirect *** example,the presence of non-host species can reduce contact rates of the main reservoir host and thus reduce the risk of transmission(“dilution effect”).In addition,an overlap in ecological niches between two species could lead to increased interspecific competition,potentially limiting host densities and reducing density-dependent pathogen transmission *** this study,we investigated the relative impact of population-level regulation of direct and indirect drivers of the prevalence of Puumala orthohantavirus(PUUV)in bank voles(Clethrionomys glareolus)during years with high *** compiled data on small mammal community composition from four regions in Germany between 2010 and *** equation modeling revealed a strong seasonality in PUUV control mechanisms in bank *** abundance of shrews tended to have a negative relationship with host abundance,and host abundance positively influenced PUUV seroprevalence,while at the same time increasing the abundance of competing non-hosts like the wood mouse(Apodemus sylvaticus)and the yellow-neckedfield mouse(Apodemusflavicollis)were associated with reduced PUUV seroprevalence in the *** results indicate that for PUUV in bank voles,dilution is associated with increased interspecific *** pressures leading to the decline of Apodemus *** a specific habitat could lead to the amplification of mechanisms promoting PUUV transmission within the host populations.

关键词： bank vole biodiversity Puumala orthohantavirus small mammals

Wind farms increase land surface temperature and reduce vegetation productivity in the Inner Mongolia

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Geography and Sustainability 2024年第3期5卷 319-328页

作者： Luyao Liu Pengtao Liu Jiawei Yu Gang Feng Qing Zhang jens-christian Svenning Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Inner Mongolia Autonomous Region Ecological and Agricultural Meteorological Centre Hohhot 010051China e Collaborative Innovation Center for Grassland Ecological Security(Jointly Supported by the Ministry of Education of China and Inner Mongolia Autonomous Region) Hohhot 010021China Center for Ecological Dynamics in a Novel Biosphere(ECONOVO) Department of BiologyAarhus UniversityNy Munkegade 114Aarhus C DK-8000Denmark Center for Biodiversity Dynamics in a Changing World(BIOCHANGE) Department of BiologyAarhus UniversityNy Munkegade 114Aarhus C DK-8000Denmark

Wind power has been developing rapidly as a key measure to mitigate human-driven global *** under-standing of the development and impacts of wind farms on local climate and vegetation is of great importance for their rational use but is still *** this study,we combined remote sensing and on-site investigations to identify wind farm locations in Inner Mongolia and performed landscape pattern analyses using *** explored the impacts of wind farms on land surface temperature(LST)and vegetation net primary productivity(NPP)between 1990 and 2020 by contrasting these metrics in wind farms with those in non-wind farm *** results showed that the area of wind farms increased rapidly from 1.2 km2 in 1990 to 10,755 km2 in ***,wind farms are mainly clustered in three aggregation areas in the ***,wind farms increased nighttime LST,with a mean value of 0.23℃,but had minor impacts on the daytime ***,wind farms caused a decline in NPP,especially over forest areas,with an average reduction of 12.37 GC/m^(2).Given the impact of wind farms on LST and NPP,we suggest that the development of wind farms should fully consider their direct and potential *** study provides scientific guidance on the spatial pattern of future wind farms.

关键词： Wind farm Landscape pattern LST NPP Inner Mongolia

Metabolic collaboration between cells in the tumor microenvironment has a negligible effect on tumor growth

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The Innovation 2024年第2期5卷 107-114页

作者： Johan Gustafsson Fariba Roshanzamir Anders Hagnestål Sagar M.Patel Oseeyi I.Daudu Donald F.Becker Jonathan L.Robinson jens nielsen Department of Life Sciences Chalmers University of TechnologySE-41296 GothenburgSweden Hagnesia AB SE-43854 HindåsSweden Department of Biochemistry and Redox Biology Center University of Nebraska-LincolnLincolnNE 68588USA BioInnovation Institute DK2200 CopenhagenDenmark

The tumor microenvironment is composed of a complex mixture of different cell types interacting under conditions of nutrient deprivation,but the metabolism therein is not fully understood due to difficulties in measuring metabolic fluxes and exchange of metabolites between different cell types in ***-scale metabolic modeling enables estimation of such exchange fluxes as well as an opportunity to gain insight into the metabolic behavior of individual cell ***,we estimated the availability of nutrients and oxygen within the tumor microenvironment using concentration measurements from blood together with a metabolite diffusion *** addition,we developed an approach to efficiently apply enzyme usage constraints in a comprehensive metabolic model of human *** combined modeling reproduced severe hypoxic conditions and the Warburg effect,and we found that limitations in enzymatic capacity contribute to cancer cells’preferential use of glutamine as a substrate to the citric acid ***,we investigated the common hypothesis that some stromal cells are exploited by cancer cells to produce metabolites useful for the cancer *** identified over 200 potential metabolites that could support collaboration between cancer cells and cancer-associated fibroblasts,but when limiting to metabolites previously identified to participate in such collaboration,no growth advantage was *** work highlights the importance of enzymatic capacity limitations for cell behaviors and exemplifies the utility of enzyme-constrained models for accurate prediction of metabolism in cells and tumor microenvironments.

关键词： metabolism effect limitations

Bistability theorem in a cancer model

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International Journal of Biomathematics 2018年第1期11卷 61-98页

作者： jens christian Larsen Vanlcse Alle 50 2. mr. tv2720 VanlCse Copenhagen Denmark

In this paper, I continue the study of the mathematical models presented in [J. C. Larsen, Models of cancer growth, J. Appl. Math. Comput. 53（1-2）（2015） 613-645] and [J. C. Larsen, The bistability theorem in a model of metastatic cancer, to appear in Appl. Math.]. I shall prove the bistability theorem for the ODE model from [Larsen, 2015]. It is a mass action kinetic system in the variables C cancer, GF growth factor and GI growth inhibitor. This theorem says that for some values of the parameters, there exist two positive singular points c＊＋ = （C＊＋, GF＊., GI＊＋）, c＊2- = （C＊-, GF＊, GI＊-） of the vector field. Here C＊- 〈 C＊＋ and e. is stable and c＊＋ is unstable, see Sec. 2. There is also a discrete model in [Larsen, 2015], it is a linear map （T） on three-dimensional Euclidean vector space with variables （C, GF, GI）, where these variables have the same meaning as in the ODE model above. In [Larsen, 2015], I showed that one can sometimes find attine vector fields on three-dimensional Euclidean vector space whose time one map is T. I shall also show this in the present paper in a more general setting than in [Larsen, 2015]. This enables me to find an expression for the rate of change of cancer growth on the coordinate hyperplane C = 0 in Euclidean vector space. I also present an ODE model of cancer metastasis with variables C, CM, CF,GI, where C is primary cancer and CM is metastatic cancer and GF, GI are growth factors and growth inhibitors, respectively.

关键词： Immunology cancer chemotherapy immune therapy discrete dynamicalsystem Gompertz function.

Editorial for “Biointelligent manufacturing in Memorium of Arnold (Arny) L. Demain”

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Synthetic and Systems Biotechnology 2022年第4期7卷 1185-1186页

作者： Qiang Gao jens nielsen Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education College of BiotechnologyTianjin University of Science and TechnologyTianjin300457China BioInnovation Institute Ole Maaloes Vej 3Copenhagen NDK2200Denmark

Biointelligent manufacturing is currently at the center of industrial *** biotechnology has historic roots dating thousand years back where microbial fermentation was used to preserve foods,make bread and fermented drinks,but has risen to a modern *** of the development into a modern industry was driven initially by production of antibiotics and later by production of food and feed *** this development,the late MIT emeritus Professor Arnold(Arny)Lester Demain was one of the drivers and is considered one of the founders of industrial *** research founds wide applications and he stands as one of the giants in the field of industrial microbiology and biotechnology[1-7].

关键词： Arnold biotechnology initially