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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

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

Graphene binding on black phosphorus enables high on/off ratios and mobility

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National Science Review 2024年第2期11卷 188-195页

作者： fanrong Lin Zhonghan Cao feiping Xiao Jiawei Liu Jiabin Qiao Minmin Xue Zhili Hu Ying Liu Huan Lu Zhuhua Zhang jens Martin Qingjun Tong Wanlin Guo Yanpeng Liu Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education State Key Laboratory of Mechanics and Control of Mechanical Structures and Institute for Frontier Science Nanjing University of Aeronautics and Astronautics Centre for Advanced 2D Materials National University of Singapore School of Physics and Electronics Hunan University Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and MeasurementSchool of PhysicsBeijing Institute of Technology Leibniz Institute für Kristallzüchtung

Graphene is one of the most promising candidates for integrated circuits due to its robustness against short-channel effects, inherent high carrier mobility and desired gapless nature for Ohmic contact, but it is difficult to achieve satisfactory on/off ratios even at the expense of its carrier mobility, limiting its device applications. Here, we present a strategy to realize high back-gate switching ratios in a graphene monolayer with well-maintained high mobility by forming a vertical heterostructure with a black phosphorus multi-layer. By local current annealing, strain is introduced within an established area of the graphene, which forms a reflective interface with the rest of the strain-free area and thus generates a robust off-state via local current depletion. Applying a positive back-gate voltage to the heterostructure can keep the black phosphorus insulating, while a negative back-gate voltage changes the black phosphorus to be conductive because of hole accumulation. Then, a parallel channel is activated within the strain-free graphene area by edge-contacted electrodes, thereby largely inheriting the intrinsic carrier mobility of graphene in the on-state. As a result, the device can provide an on/off voltage ratio of >10～3 as well as a mobility of ～8000 cm2V-1s-1at room temperature, meeting the low-power criterion suggested by the International Roadmap for Devices and Systems.

关键词： graphene on/off ratio mobility black phosphorus reflective interface

Deep hyperammonemic hepatic encephalopathy precipitated by fecal microbiota transplantation for fulminant Clostridioides difficile infection

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Gastroenterology Report 2022年第1期10卷 612-614页

作者： Lotte Lindgreen Eriksen Simon Mark Dahl Baunwall Peter Lykke Eriksen Kirstine Petrea Bak-fredslund jens Erik Nielsen jens frederik dahlerup Karen Louise Thomsen Hendrik Vilstrup Christian Lodberg Hvas Department of Hepatology and Gastroenterology Aarhus University HospitalAarhus NDenmark Department of Hepatology and Gastroenterology Randers Regional HospitalRandersDenmark Department of Radiology Aarhus University HospitalAarhus NDenmark

Introduction fecal microbiota transplantation(fMT)is highly effective and potentially life-saving for recurrent Clostridioides difficile infection(CDI)[1].Recent pilot trials also reported the use of fMT to revert hepatic encephalopathy(HE)in patients with decompensated liver cirrhosis without infectious colitis[2,3].Intestinal microbiota-driven hyperammonemia is central to HE development and most treatments aim to reduce ammonia levels by modulating the intestinal ***,fMT might lead to increased intestinal ammonia production,as we describe here.

关键词： hepatic infection encephalopathy

fully integrated and broadband Si-rich silicon nitride wavelength converter based on Bragg scattering intermodal four-wave mixing

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Photonics Research 2024年第3期12卷 I0001-I0010页

作者： VALERIO VITALI THALÍA DOMÍNGUEZ BUCIO HAO LIU JOSÉMANUEL LUQUE GONZÁLEZ fRANCISCO JURADO-ROMERO ALEJANDRO ORTEGA-MOÑUX GLENN CHURCHILL JAMES C.GATES JAMES HILLIER NIKOLAOS KALfAGIANNIS DANIELE MELATI jens H.SCHMID ILARIA CRISTIANI PAVEL CHEBEN J.GONZALO WANGÜEMERT-PÉREZ ÑIGO MOLINA-fERNÁNDEZ fREDERIC GARDES COSIMO LACAVA PERIKLIS PETROPOULOS Optoelectronics Research Centre University of SouthamptonSouthampton SO171BJUK Electrical Computer and Biomedical Engineering DepartmentUniversity of PaviaPavia 27100Italy Telecommunication Research Institute(TELMA) Universidad de MálagaCEI Andalucı´a TECHE.T.S.I.Telecomunicación29010 MálagaSpain School of Science and Technology Nottingham Trent UniversityNottingham NG118NSUK Department of Electrical Engineering Eindhoven University of TechnologyEindhoven 5600 MBThe Netherlands Department of Materials Science and Engineering University of IoanninaIoannina 45110Greece Centre de Nanosciences et de Nanotechnologies UniversitéParis-SaclayCNRS91120 PalaiseauFrance Advanced Electronics and Photonics Research Center National Research Council CanadaOttawaOntario K1A 0R6Canada

Intermodal four-wave mixing(fWM)processes have recently attracted significant interest for all-optical signal processing applications thanks to the possibility to control the propagation properties of waves exciting distinct spatial modes of the same *** allows,in principle,to place signals in different spectral regions and satisfy the phase matching condition over considerably larger bandwidths compared to intramodal ***,the demonstrations reported so far have shown a limited bandwidth and suffered from the lack of on-chip components designed for broadband manipulation of different *** demonstrate here a silicon-rich silicon nitride wavelength converter based on Bragg scattering intermodal fWM,which integrates mode conversion,multiplexing and de-multiplexing functionalities *** system enables wavelength conversion between pump waves and a signal located in different telecommunication bands(separated by 60 nm)with a 3 dB bandwidth exceeding 70 nm,which represents,to our knowledge,the widest bandwidth ever achieved in an intermodal fWM-based system.

关键词： scattering pump modal

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利用择形分子筛异构化亚甲基二苯胺

Chinese Journal of Catalysis 2024年第7期62卷 124-130页

作者： Sam Van Minnebruggen Ka Yan Cheung Trees De Baerdemaeker Niels Van Velthoven Matthias Degelin Galahad O’Rourke Hiroto Toyoda Andree Iemhoff Imke Muller Andrei-Nicolae Parvulescu Torsten Mattke jens ferbitz 吴勤明肖丰收 Toshiyuki Yokoi Nils Bottke Dirk De Vos 巴斯夫股份有限公司膜分离、吸附、催化和光谱学可持续解决方案中心(cMACS) 比利时巴斯夫股份有限公司研究组德国东京工业大学纳米空间催化研究所横滨日本浙江大学化学系浙江杭州310028

亚甲基二苯胺(MDA)被广泛用作生产聚氨酯和聚异氰脲酸酯的中间体.然而,当前MDA的生产工艺在控制(4,4’/(2,4’+2,2’))异构体比例方面还存在局限.其中,4,4’-MDA被认为是最有价值的异构体.尽管2,4'-MDA在市场上也有一定的需求,但如果能... 详细信息

亚甲基二苯胺(MDA)被广泛用作生产聚氨酯和聚异氰脲酸酯的中间体.然而,当前MDA的生产工艺在控制(4,4’/(2,4’+2,2’))异构体比例方面还存在局限.其中,4,4’-MDA被认为是最有价值的异构体.尽管2,4'-MDA在市场上也有一定的需求,但如果能将其有效地转化为4,4'-MDA,将能显著提升其附加值.本文在使用苯胺的条件下,利用β分子筛等催化剂,通过双分子机制,可以选择性地将2,4'-MDA异构化为4,4'-MDA.尽管实验显示,多种酸性沸石具有较高的异构化活性,但MCM-68(具有MSE拓扑结构)的催化性能尤为出色,它不仅展现出高异构化活性,而且具有很好的选择性.MCM-68主要催化2,4'-MDA异构化为4,4'-MDA,而2,2'-MDA和低聚物的形成则可以忽略不计.本文还深入探讨了该择形作用的原因,并详细研究了酸位置在MSE分子筛孔道限制中的关键作用.

关键词：铝分布多相催化异构化亚甲基二苯胺聚氨酯择形

Obeticholic acid for severe bile acid diarrhea with intestinal failure:A case report and review of the literature

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World Journal of Gastroenterology 2018年第21期24卷 2320-2326页

作者： Christian Lodberg Hvas Peter Ott Peter Paine Simon Lal Soren Peter Jorgensen jens frederik dahlerup Department of Hepatology and Gastroenterology Aarhus University HospitalAarhus C 8000Denmark Department of Gastroenterology Salford Royal NHS Foundation TrustSalfordManchester M6 8HDUnited Kingdom

Bile acid diarrhea results from excessive amounts of bile acids entering the colon due to hepatic overexcretion of bile acids or bile acid malabsorption in the terminal ileum. The main therapies include bile acid sequestrants, such as colestyramine and colesevelam, which may be given in combination with the opioid receptor agonist loperamide. Some patients are refractory to conventional treatments. We report the use of the farnesoid X receptor agonist obeticholic acid in a patient with refractory bile acid diarrhea and subsequent intestinal failure. A 32-year-old woman with quiescent colonic Crohn's disease and a normal terminal ileum had been diagnosed with severe bile acid malabsorption and complained of watery diarrhea and fatigue. The diarrhea resulted in hypokalemia and sodium depletion that made her dependent on twice weekly intravenous fluid and electrolyte infusions. Conventional therapies with colestyramine, colesevelam, and loperamide had no effect. Second-line antisecretory therapies with pantoprazole, liraglutide, and octreotide also failed. Third-line treatment with obeticholic acid reduced the number of stools from an average of 13 to an average of 7 per 24h and improved the patient's quality of life. The fluid and electrolyte balances normalized. The effect was sustained during follow-up for 6 mo with treatment at a daily dosage of 25 mg. The diarrhea worsened shortly after cessation of obeticholic acid. This case report supports the initial report that obeticholic acid may reduce bile acid production and improve symptoms in patients with bile acid diarrhea.

关键词： Bile acid malabsorption Diarrhea farnesoid X-activated receptor Crohn’s disease

i2dash:Creation of flexible,Interactive,and Web-based Dashboards for Visualization of Omics Data

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Genomics, Proteomics & Bioinformatics 2022年第3期20卷 568-577页

作者： Arsenij Ustjanzew jens Preussner Mette Bentsen Carsten Kuenne Mario Looso Max Planck Institute for Heart and Lung Research Bioinformatics UnitD-61231 Bad NauheimGermany

Data visualization and interactive data exploration are important aspects of illustrating complex concepts and results from analyses of omics data.A suitable visualization has to be intuitive and ***-based dashboards have become popular tools for the arrangement,consolidation,and display of such ***,the combination of automated data processing pipelines handling omics data and dynamically generated,interactive dashboards is poorly ***,we present i2dash,an R package intended to encapsulate functionality for the programmatic creation of customized *** supports interactive and responsive(linked)visualizations across a set of predefined graphical layouts.i2dash addresses the needs of data analysts/software developers for a tool that is compatible and attachable to any R-based analysis pipeline,thereby fostering the separation of data visualization on one hand and data analysis tasks on the other *** addition,the generic design of i2dash enables the development of modular extensions for specific *** a proof of principle,we provide an extension of i2dash optimized for single-cell RNA sequencing analysis,supporting the creation of dashboards for the visualization needs of such *** with these features,i2dash is suitable for extensive use in large-scale sequencing/bioinformatics *** this line,we provide i2dash as a containerized solution,enabling a straightforward large-scale deployment and sharing of dashboards using cloud services.i2dash is freely available via the R package archive CRAN(https://***/package=i2dash).

关键词： Data visualization Dashboard Cloud Data analysis Automation

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草地灌溉对土壤性质和植物物种组成的影响

Journal of Plant Ecology 2023年第2期16卷 174-188页

作者： Rebekka Gerlach Constanze Buhk jens Schirmel Hermann f.Jungkunst iES Landau Institute of Environmental SciencesGeoecology and Physical Geography/Ecosystem AnalysisUniversity of Koblenz-LandauLandauGermany

草地是欧洲范围内生物物种最为丰富的动植物栖息地之一;为了对大面积的草地开展有效的保护,必须要采取具有针对性和可持续性的管理措施。虽然如今大都已被弃用,但传统上的灌溉却有可能是一种具有可持续性的管理策略。然而,对于一般的湿... 详细信息

草地是欧洲范围内生物物种最为丰富的动植物栖息地之一;为了对大面积的草地开展有效的保护,必须要采取具有针对性和可持续性的管理措施。虽然如今大都已被弃用,但传统上的灌溉却有可能是一种具有可持续性的管理策略。然而,对于一般的湿润性生态区域,人们还不太了解灌溉、土壤特性以及植物物种这3者之间的相互影响。我们旨在将传统的草地灌溉对植物群落的影响从传统的低施肥量效应中分离出来,从而获得植物生态学方面的新知识。我们的考察对象是植物的组成和多样性以及它们与土壤特性(有机态碳、总氮、持水性/保水力、中型土壤动物活力)和土壤养分(无机态氮、磷、钾、镁、硼)指标之间的潜在联系。在田间研究中,我们对过去长期灌溉的13块草地以及未经灌溉的13块草地(其中17块草地经过施肥,9块未经施肥)进行了比较。分析这些草地在一整年时间内的植物多样性和物种组成情况以及土壤养分和土壤特性指标,并且假设不同年份之间的差异不大。研究结果发现,灌溉和施肥使土壤特性和土壤养分发生了改变,但它们对植物物种多样性并无影响,只影响植物的物种组成。淤积土具有更细的粒度,因而拥有更高的保水力和养分储量。因此,需要获取水分和养分资源的禾本科植物在经过灌溉的草地上占据优势。本研究的结果表明,对于中欧地区大量的已开发草地,灌溉不仅能保护其生物多样性,而且还有可能使其植物具有不同的植物功能性状。

关键词：草场洪水灌溉施肥土壤养分植物多样性物种组成土壤模式