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Influence of rolling friction on single spout fluidized bed simulation

Particuology 2012年第5期10卷 582-591页

作者： Christoph Goniva Christoph Kloss Niels G. Deen johannes a.m.kuipers Stefan Pirker Christian-Doppler Laboratory on Particulate Flow modelling Johannes Kepler UniversityLinz Austria DCS Computing GmbH Linz Austria Christian-Doppler Laboratory on Particulate Flow modelling Johannes Kepler UniversityLinz Austria Department of Chemical Engineering and Chemistry Eindhoven University of TechnologyEindhovenThe Netherlands Department of Chemical Engineering and Chemistry Eindhoven University of TechnologyEindhovenThe Netherlands Christian-Doppler Laboratory on Particulate Flow modelling Johannes Kepler UniversityLinzAustria Institute of Fluid mechanics and Heat Transfer Johannes Kepler UniversityLinzAustria

In this paper we study the effect of rolling friction on the dynamics in a single spout fluidized bed using Discrete Element method （DEm） coupled to Computational Fluid Dynamics （CFD）. In a first step we neglect rolling friction and show that the results delivered by the open source CFD-DEm framework applied in this study agree with previous simulations documented in literature. In a second step we include a rolling friction sub-model in order to investigate the effect of particle non-sphericity. The influence of particle-particle as well as particle-wall rolling friction on the flow in single spout fluidized bed is studied separately. Adequate rolling friction model parameters are obtained using first principle DEm simulations and data from literature. Finally, we demonstrate the importance of correct modelling of rolling friction for coupled CFD-DEm simulations of spout fluidized beds. We show that simulation results can be improved significantly when applying a rolling friction model, and that experimental data from literature obtained with Positron Emission Particle Trackin~ fPEPT） technique can be satisfactorily reoroduced.

关键词： CFD-DEmOpen sourceRolling frictionSpout fluidized bedNon-sphericity

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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

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Genomic mosaicism of the Brain:Origin,Impact,and Utility

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Neuroscience Bulletin 2024年第6期40卷 759-776页

作者： Jared H.Graham johannes C.m.Schlachetzki Xiaoxu Yang martin W.Breuss Department of Pediatrics Section of Clinical Genetics and MetabolismUniversity of Colorado School of MedicineAurora80045-2581COUSA Department of Cellular and molecular medicine University of California San DiegoLa Jolla92093-0021San DiegoCAUSA Department of Neurosciences University of California San DiegoLa Jolla92093-0021San DiegoCAUSA Rady Children’s Institute for Genomic medicine San Diego92123CAUSA

Genomic mosaicism describes the phenomenon where some but not all cells within a tissue harbor unique genetic ***,research focused on the impact of genomic mosaicism on clinical phenotype—motivated by its involvement in cancers and overgrowth *** recently,we increasingly shifted towards the plethora of neutral mosaic variants that can act as recorders of cellular lineage and environmental ***,we summarize the current state of the field of genomic mosaicism research with a special emphasis on our current understanding of this phenomenon in brain development and *** the field of genomic mosaicism has a rich history,technological advances in the last decade have changed our approaches and greatly improved our *** will provide current definitions and an overview of contemporary detection approaches for genomic ***,we will discuss the impact and utility of genomic mosaicism.

关键词： Genomics Brain development Brain homeostasis Genomic mosaicism

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Summer Warming Limited Bud Output Drives a Decline in Daughter Shoot Biomass through Reduced Photosynthetis of Parent Shoots in Leymus chinensis Seedlings

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1667-1675页

作者： Song Gao Ruocheng Xu Lin Li Jiao Wang Nian Liu johannes m.H.Knops Junfeng Wang Graduate School Changchun UniversityChangchun130022China Key Laboratory of Vegetation Ecology Ministry of EducationInstitute of Grassland ScienceSchool of Life SciencesJilin Songnen Grassland Ecosystem National Observation and Research StationNortheast Normal UniversityChangchun130024China Jilin Agricultural Radio and Television School Changchun130599China Department of Health and Environmental Sciences Xi’an Jiaotong Liverpool UniversitySuzhou215000China

Understanding how summer warming inﬂuences the parent and daughter shoot production in a perennial clonal grass is vital for comprehending the response of grassland productivity to global ***,we conducted a simulated experiment using potted Leymus chinensis,to study the relationship between the photosynthetic activ-ity of parent shoots and the production of daughter shoots under a whole(90 days)summer warming scenario(+3°C).The results showed that the biomass of parents and buds decreased by 25.52%and 33.45%,respectively,under warming *** reduction in parent shoot biomass due to warming directly resulted from decreased leaf area(18.03%),chlorophyll a(18.27%),chlorophyll b(29.21%)content,as well as a reduction in net photosynthetic rate(7.32%)and the maximum quantum efﬁciency of photosystem II(PSII)photochemistry(4.29%).The decline in daughter shoot biomass was linked to a decrease in daughter shoot number(33.33%)by ***,the number of belowground buds increased by 46.43%.The results indicated that long-term summer warming reduces biomass accumulation in parent shoot by increasing both limitation of stoma and ***,the parent shoot allocates relatively more biomass to the belowground organs to maintain the survival and growth of ***,buds,as a potential aboveground population,could remedy for the cur-rent loss of parent shoot density by increasing the number of future daughter shoots if summer warming subsides.

关键词： Warming parent shoot bud bank photosynthesis chlorophyllﬂuorescence Leymus chinensis

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Two-fluid modeling of Geldart A particles in gas-fluidized beds

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Particuology 2008年第6期6卷 540-548页

作者： m.A. van der Hoef J.A.m. kuipers Faculty of Science & Technology University of Twente

We have investigated the effect of cohesion and drag models on the bed hydrodynamics of Geldart A particles based on the two-fluid （TF） model. For a high gas velocity U0 = 0.03 m/s, we found a transition from the homogeneous fluidization to bubbling fluidization with an increase of the coefficient C1, which is used to account for the contribution of cohesion to the excess compressibility. Thus cohesion can play a role in the bed expansion of Geldart A particles. Apart from cohesion, we have also investigated the influence of the drag models. When using the Wen and Yu drag correlation with an exponent n = 4.65, we find an under-prediction of the bed expansion at low gas velocities （U0 = 0.009 m/s）. When using a larger exponent （n = 9.6）, as reported in experimental studies of gas-fluidization, a much better agreement with the experimental bed expansion is obtained. These findings suggest that at low gas velocity, a scale-down of the commonly used drag model is required. On the other hand, a scale-up of the commonly used drag model is necessary at high gas velocity （U0 = 0.2 and 0.06 m/s）. We therefore conclude that scaling the drag force represent only an ad hoc way of repairing the deficiencies of the TF model, and that a far more detailed study is required into the origin of the failure of the TF model for simulating fluidized beds of fine powders.

关键词： Gas-fluidized bed Geldart A particles Two-fluid model Cohesive force Drag correlation

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Landscape of global urban environmental resistome and its association with local socioeconomic and medical status

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Science China(Life Sciences) 2024年第6期67卷 1292-1301页

作者： Jun Wu Yige Hu michael H Perlin David Danko Jun Lu manuela Oliveira johannes Werner maria m Zambrano maria A Sierra Olayinka O Osuolale Paweł Łabaj Nicolás Rascovan Nur Hazlin Hazrin-Chong Soojin Jang Haruo Suzuki marina Nieto-Caballero Bharath Prithiviraj Patrick K H Lee Agnieszka Chmielarczyk Anna Różańska Yongxiang Zhao Lan Wang Christopher E mason Tieliu Shi Center for Bioinformatics and Computational Biology and the Institute of Biomedical SciencesSchool of Life SciencesEast China Normal UniversityShanghai 200241China Department of Biology Program on Disease EvolutionUniversity of LouisvilleLouisville 40292USA Weill Cornell medicine New York 10065USA The Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine New York 10065USA Department of Pulmonary medicine Shanghai Chest HospitalShanghai Jiao Tong UniversityShanghai 200025China i3S-Instituto de Investiga玢o e Inova玢o em Saúde Universidade do PortoPorto 4050-290Portugal Ipatimup-Instituto de Patologia e Imunologia molecular da Universidade do Porto Porto 4200-465Portugal Departamento de Biologia Faculdade de CiênciasUniversidade do PortoPorto 4050-290Portugal High Performance and Cloud Computing Group Zentrum für Datenverarbeitung(ZDV)Eberhard Karls University of TübingenW鋍hterstra遝7672074TübingenGermany Corporación Corpogen Research Center Bogotá110311Colombia Applied Environmental metagenomics and Infectious Diseases Research(AEmIDR) Department of Biological SciencesElizade UniversityIlara-Mokin 340271Nigeria maopolska Centre of Biotechnology Jagiellonian UniversityKraków 30-005Poland Aix-marseille Université Mediterranean Institute of OceanologyUniversitéde ToulonCNRSIRDUM 110Marseille 83041France Department of Biological Sciences and Biotechnology Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 UKM BangiSelangor Institut Pasteur Korea Seoul 13488Republic of Korea Faculty of Environment and Information Studies Keio UniversityFujisawaKanagawa 252-0882Japan University of Colorado at Boulder CivilEnvironmental and Architectural DepartmentBoulder 80303USA Brooklyn College of the City University of New York Brooklyn 11210USA School of Energy and Environment City University of Hong KongHong Kong 999077China Department of microbiology Faculty of MedicineJagiellonian UniversityKraków 30-005Poland Biological Targeting Diagnosis and The

Antimicrobial resistance(AmR)poses a critical threat to global health and development,with environmental factors—particularly in urban areas—contributing significantly to the spread of antibiotic resistance genes(ARGs).However,most research to date has been conducted at a local level,leaving significant gaps in our understanding of the global status of antibiotic resistance in urban *** address this issue,we thoroughly analyzed a total of 86,213 ARGs detected within 4,728 metagenome samples,which were collected by the meta SUB International Consortium involving diverse urban environments in 60 cities of 27 countries,utilizing a deep-learning based *** findings demonstrated the strong geographical specificity of urban environmental resistome,and their correlation with various local socioeconomic and medical *** also identified distinctive evolutionary patterns of ARG-related biosynthetic gene clusters(BGCs)across different countries,and discovered that the urban environment represents a rich source of novel *** study provides a comprehensive overview of the global urban environmental resistome,and fills a significant gap in our knowledge of large-scale urban antibiotic resistome analysis.

关键词： urban environment metagenome antibiotic resistance resistance diversity biosynthetic gene clusters

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Two-fluid modelling for cylindrical fluidized beds using kinetic theory for rough spheres

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Particuology 2020年第3期18卷 25-34页

作者： Lei Yang J.T.Padding J.a.m.kuipers Helmholtz Institute Erlangen-Nürnberg for Renewable Energy(IEK-11) Fürther Straβe 24890429 NurnbergGermany Department of Process and Energy Delft University of Technology2628CB DelftThe Netherlands Department of Chemical Engineering and Chemistry Eindhoven University of Technology5600MB EindhovenThe Netherlands

Recently,we have extended the kinetic theory of granular flow (KTGF) to include friction between the spherical particles and tested it in rectangular *** this study,the extended KTGF implemented in cylindrical coordinates is used to model the more-commonly employed cylindrical bubbling fluidized *** attention is paid to the anti-symmetric part of the velocity gradient in the solids stress *** verification of the implementation,a comparison of the present model in the limit of zero friction with the original (frictionless) KTGF model was ***,simulations of bubbling fluidized beds of inelastic particles were performed using our extended KTGF and an effective KTGF model for inelastic particles of Jenkins and *** simulation results show good agreement for the time-averaged solids volume fraction distribution and solids circulation ***,our model is validated by predicting the individual bubble behavior in dense bubbling fluidized beds containing different granular materials in a comparison with experimental data from Verma et al.(2014).The extended KTGF leads to an improved agreement with experimental bubble *** to previous work (Yang et al.,2016b,2017c),and by introducing cylindrical coordinates,the current work demonstrates that the extended KTGF improves predictions for the temporal bubble behavior of cylindrical fluidized beds.

关键词： Fluidization Frictional collision Rough particles Cylindrical bed hydrodynamics Two-fluid model

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Piezo1 expression in chondrocytes controls endochondral ossification and osteoarthritis development

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Bone Research 2024年第1期12卷 199-214页

作者： Laura J.Brylka Assil-Ramin Alimy miriam E.A.Tschaffon-müller Shan Jiang Tobias malte Ballhause Anke Baranowsky Simon von Kroge Julian Delsmann Eva Pawlus Kian Eghbalian Klaus Püschel Astrid Schoppa melanie Haffner-Luntzer David J.Beech Frank Timo Beil michael Amling johannes Keller Anita Ignatius Timur A.Yorgan Tim Rolvien Thorsten Schinke Department of Osteology and Biomechanics University Medical Center Hamburg-Eppendorf20246 HamburgGermany Department of Trauma and Orthopedic Surgery University Medical Center Hamburg-Eppendorf20246 HamburgGermany Institute of Orthopedic Research and Biomechanics University Medical Center UlmBadenWürttemberg89081 UlmGermany Department Legal medicine University Medical Center Hamburg-Eppendorf20246 HamburgGermany Leeds Institute of Cardiovascular and metabolic medicine School of MedicineUniversity of LeedsLS29JT LeedsUK

Piezo proteins are mechanically activated ion channels,which are required for mechanosensing functions in a variety of cell *** we and others have previously demonstrated that the expression of Piezo1 in osteoblast lineage cells is essential for boneanabolic processes,there was only suggestive evidence indicating a role of Piezo1 and/or Piezo2 in *** we addressed the question if and how chondrocyte expression of the mechanosensitive proteins Piezo1 or Piezo2 controls physiological endochondral ossification and pathological osteoarthritis(OA)*** with chondrocyte-specific inactivation of Piezo1(Piezo1^(Col2a1Cre)),but not of Piezo2,developed a near absence of trabecular bone below the chondrogenic growth plate ***,all Piezo1^(Col2a1Cre) animals displayed multiple fractures of rib bones at 7 days of age,which were located close to the growth *** skeletal growth was only mildly affected in these mice,OA pathologies were markedly less pronounced compared to littermate controls at 60 weeks of ***,when OA was induced by anterior cruciate ligament transection,only the chondrocyte inactivation of Piezo1,not of Piezo2,resulted in attenuated articular cartilage ***,osteophyte formation and maturation were also reduced in Piezo1^(Col2a1Cre) *** further observed increased Piezo1 protein abundance in cartilaginous zones of human ***,we identified Ptgs2 and Ccn2 as potentially relevant Piezo1 downstream genes in ***,our data do not only demonstrate that Piezo1 is a critical regulator of physiological and pathological endochondral ossification processes,but also suggest that Piezo1 antagonists may be established as a novel approach to limit osteophyte formation in OA.

关键词： Piezo1 markedly ossification

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Clinical-based phenotypes in children with pediatric post-COVID-19 condition

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World Journal of Pediatrics 2024年第7期20卷 682-691页

作者： Lieke C.E.Noij Jelle m.Blankestijn Coen R.Lap marlies A.van Houten Giske Biesbroek Anke-Hilse maitland-van der Zee mahmoud I.Abdel-Aziz johannes B.van Goudoever mattijs W.Alsem Caroline L.H.Brackel Kim J.Oostrom Simone Hashimoto Suzanne W.J.Terheggen-Lagro Department of Pediatric Pulmonology and Allergy Amsterdam UMCLocation AMCEmma Children’s HospitalAmsterdam University Medical CenterRoom G2-222Meibergdreef 91105AZAmsterdamThe Netherlands Department of Pulmonary medicine Amsterdam UMCAmsterdamThe Netherlands Department of Pediatrics Spaarne GasthuisHoofddorpThe Netherlands Department of Pediatrics Emma Children’s HospitalAmsterdam University Medical CenterAmsterdamThe Netherlands Department of Rehabilitation medicine Amsterdam Movement SciencesMeibergdreef 9AmsterdamThe Netherlands Department of Paediatric Pulmonology Department of PaediatricsTergooi MCHilversumThe Netherlands Department of Child and Adolescent Psychiatry and Psychosocial Care Amsterdam UMCAmsterdam Reproduction and DevelopmentAmsterdamThe Netherlands

Background Pediatric post coronavirus disease 2019(COVID-19)condition(PPCC)is a heterogeneous syndrome,which can significantly affect the daily lives of *** study aimed to identify clinically meaningful phenotypes in children with PPCC,to better characterize and treat this *** Participants were children with physician-diagnosed PPCC,referred to the academic hospital Amsterdam UmC in the Netherlands between November 2021 and march *** factors and information on post-COVID symptoms,comorbidities,and impact on daily life were *** clusters were identified using an unsupervised and unbiased approach for mixed data *** Analysis of 111 patients(aged 3–18 years)revealed three distinct clusters within *** 1(n=62,median age=15 years)predominantly consisted of girls(74.2%).These patients suffered relatively more from exercise intolerance,dyspnea,and smell *** 2(n=33,median age=13 years)contained patients with an even gender distribution(51.5%girls).They suffered from relatively more sleep problems,memory loss,gastrointestinal symptoms,and *** 3(n=16,median age=11 years)had a higher proportion of boys(75.0%),suffered relatively more from fever,had significantly fewer symptoms(median of 5 symptoms compared to 8 and 10 for clusters 1 and 2 respectively),and experienced a lower impact on daily *** This study identified three distinct clinical PPCC phenotypes,with variations in sex,age,symptom patterns,and impact on daily *** findings highlight the need for further research to understand the potentially diverse underlying mechanisms contributing to post-COVID symptoms in children.

关键词： Adolescents Clusters Long COVID Pediatric Phenotypes Post-COVID syndrome

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Development and Optimization of Universal Bone Conduction Hearing Spectacles

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International Journal of Otolaryngology and Head & Neck Surgery 2024年第5期13卷 344-358页

作者： johannes Burkart mona Kirstin Fehling Saadu Adamu Raúl Pérez Ramos Daniel Häussler Department of Otorhinolaryngology Head and Neck Surgery University Hospital Mannheim Mannheim Germany National Ear Care Centre Kaduna Nigeria School of Advanced Education Research and Accreditation University Isabel I Castelln de la Plana Spain

Background: Non-implantable bone anchored hearing devices (BCHDs) are utilized for patients with conductive or mixed hearing loss who are unsuitable for conventional hearing aids or have unresolved middle ear issues. These devices can be surgically implanted or attached using adhesive plates, dental sticks, elastic headbands, or bone conduction spectacles. Optimal fitting of bone conduction spectacles requires appropriate frame selection and contact pressure in the temporal and mastoid areas. The ANSI S3.6 and DIN EN ISO 389-3 standards recommend a contact area of approximately 1.75 cm2 and a maximum force of 5.4 N for effective sound transmission and comfort. methods: This study aimed to evaluate the technical fit and mechanical stability of universal bone conduction hearing spectacles compared to established systems. A Sen-Pressure 02 thin-film sensor connected to an Arduino Uno R3 board measured contact force in the temporal and mastoid areas. Several BCHDs were tested, including the Bruckhoff la belle BC D50/70, Radioear B71 headset, Radioear B71 elastic headband, Cochlear Baha SoundArc m, and Cochlear Baha elastic headband, on a PVC artificial head, with data analyzed using ANOVA and LSD post hoc tests. Results: The la belle BC D50/70 spectacles showed comparable contact force to established BCHDs, ensuring adequate sound transmission and comfort. Significant differences were observed between the systems, with the Radioear B71 headset exhibiting the highest forces. The la belle BC D50/70 had similar forces to the Radioear B71 elastic headband. Conclusion: The la belle BC D50/70 universal bone conduction hearing spectacles are a technically equivalent alternative to established BCHDs, maintaining pressure below 5.4 N. Future research should explore the impact of different contact forces on performance and comfort, and the integration of force control in modified spectacles. This study indicates that the la belle BC D50/70 is a viable alternative that meets audio

关键词： Bone Conduction Hearing Devices (BCHD) Universal Bone Conduction Hearing Spec-Tacles Non-Implantable Hearing Aids Contact Pressure Optimization

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