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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

Tensile deformation of fine-grained mg at 4K,78K and 298K

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Journal of magnesium and Alloys 2024年第6期12卷 2534-2556页

作者： m.Walag A.Kula P.Noga T.Tokarski G.Cios m.Niewczas AGH University of Krakow Faculty of Non-Ferrous MetalsKrakowPoland AGH University of Krakow Academic Centre for Materials and NanotechnologyKrakowPoland materials Science and Engineering McMaster UniversityHamiltonCanada

The impact of grain size, ranging from 0.9 μm to 9 μm, on the mechanical properties of commercially pure mg is investigated at temperatures of 4K, 78K, and 298K. The mechanisms governing plastic flow are influenced by both grain size and temperature. At 4K and 78K, dominant deformation modes in mg involve dislocation glide and extension twinning, regardless of grain size. The interactions between basal and non-basal dislocations and dislocations with grain boundaries promote an unusually high rate of work hardening in the plastic regime, leading to premature failure. The yield stress follows the Hall-Petch relationship σy~ k/√d, with the slope k increasing with decreasing temperature. At 298K, in addition to dislocation glide and twinning, grain boundary sliding(GBS) becomes significant in samples with grain sizes below 3 μm, considerably enhancing the material's deformability. GBS activation provides an additional recovery mechanism for dislocations accumulating at grain boundaries, facilitating their absorption during sliding and rotation. Analysis of σ Θ relationship suggests that the basal slip is the dominant dislocation mode in mg at 298K. Decreasing grain size suppresses dislocation activity and twinning and increases GBS, resulting in lower Θ and σ Θ values. Suppressing conventional deformation modes coupled with enhanced GBS yields stress softening, breaking down the Hall-Petch relationship in mg below 3 μm grain size, leading to an inverse Hall-Petch behaviour. The work reports new data on the strength, ductility, work hardening and fracture behaviour, and their variations with mg grain size across different temperature regimes.

关键词： Polycrystalline mg mechanical properties Deformation mechanisms Work-hardening Texture evolution Cryogenic temperatures Hall-Petch relationship

Association between Exposure to metals during Pregnancy,Childhood Gut microbiome,and Risk of Intestinal Inflammation in Late Childhood

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Environment & Health 2024年第10期2卷 739-749页

作者： Vishal midya manasi Agrawal Jamil m.Lane Chris Gennings Leonid Tarassishin Libni A.Torres-olascoaga Joseph Eggers Jill K.Gregory mellissa Picker Inga Peter Jeremiah J.Faith manish Arora martha m.Tellez-Rojo Robert o.Wright Jean-Frederic Colombel Shoshannah Eggers Department of Environmental medicine and Climate Science Icahn School of Medicine at Mount SinaiNew York 10029-6574New YorkUnited States Division of Gastroenterology Icahn School of Medicine at Mount SinaiNew York 10029-6574New YorkUnited States Center for molecular Prediction of Inflammatory Bowel Disease(PREDICT) Department of Clinical MedicineAalborg UniversityCopenhagen 9220Denmark Department of Genetics and Genomic Sciences Icahn School of MedicineNew York 10029-6574New YorkUnited States Center for Research on Nutrition and Health National Institute of Public HealthCuernavaca 62508Mexico Department of Immunology and Immunotherapy Icahn School of Medicine at Mount SinaiNew York 10029-6574New YorkUnited States Department of Epidemiology University of Iowa College of Public HealthIowa City 52242 IowaUnited States Instructional Technology Group Icahn School of Medicine at Mount SinaiNew York 10029-6574New YorkUnited States

Alterations to the gut microbiome and exposure to metals during pregnancy have been suggested to impact inflammatory bowel ***,how prenatal exposure to metals eventually results in long-term effects on the gut microbiome,leading to subclinical intestinal inflammation,particularly during late childhood,has not been *** is also unknown whether such an interactive effect drives a specific subgroup of children toward elevated susceptibility to intestinal *** used an amalgamation of machine-learning techniques with a regression-based framework to explore if children with distinct sets of gut microbes and certain patterns of exposure to metals during pregnancy(metal−microbial clique signature)had a higher likelihood of intestinal inflammation,measured based on fecal calprotectin(FC)in late *** obtained samples from a well-characterized longitudinal birth cohort from mexico City(n=108),*** the second and third trimesters of pregnancy,11 metals were measured in whole *** microbial abundances and FC were measured in stool samples from children 9−11 years of *** FC was defined as having FC above 100μg/g of *** identified subgroups of children in whom microbial and metal−microbial clique signatures were associated with elevated FC(false discovery rate(FDR)ound two metal−microbial clique signatures significantly associated with elevated FC:(1)low cesium(Cs)and copper(Cu)in the third trimester and low relative abundance of Eubacterium ventriosum(oR[95%CI]:10.27[3.57,29.52],FDRow Cu in the third trimester and high relative abundances of Roseburia inulinivorans and Ruminococcus torques(oR[95%CI]:7.21[1.81,28.77],FDRoratory study demonstrates that children with specific gut microbes and specific exposure patterns to metals during pregnancy may have higher fecal calprotectin levels in late childhood,denoting an elevated risk of intestinal inflammation.

关键词： exposome metals machine learning microbiome environmental epidemiology intestinal inflammation

Sodium nitroprusside as a signal molecule for up-regulating membrane characteristics,antioxidant defense system to improve flax productivity under water stress

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oil Crop Science 2024年第3期9卷 160-169页

作者： N.m.Al-Ashkar B.A.Bakry H.m.S.El-Bassiouny m.m.S.Abdallah m.S.Sadak Botany Department Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt Field Crops Research Department Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt

Water stress is a critical environmental adversity that significantly impacts the growth,development,and yield of flax *** this study,flax seeds were cultivated under different water irrigation requirements(WIR)(100%,75%,and 50%)to investigate the effects of exogenously supplied nitric oxide(No)donor sodium nitroprusside(SNP)as foliar treatments at concentrations of 0.0 mmol/L,0.5 mmol/L,1.0 mmol/L,and 2.0 mmol/*** stress led to a significant decrease in plant growth,photosynthetic pigments,yield components such as oil and total carbohydrate *** also resulted in an increase in leaf H2o2 production,lipid peroxidation levels and activities of enzymatic antioxidants including polyphenol oxidase,superoxide dismutase,and nitrate reductase ***,foliar application of SNP improved photosynthetic pigments and antioxidant defense system which mitigated the negative impact of water stress on growth and yield productivity by reducing oxidative damage caused by reactive oxygen species *** use of SNP also decreased H_(2)o_(2) accumulation levels,lipid peroxidation levels,and improved membrane *** treatment at concentration of 2 mmol/L showed superior results compared to other concentrations with extremely significant increases observed in yield characteristics such as oil content,total carbohydrate percentages,and unsaturated fatty acids to saturated fatty acids ratio.

关键词： Flax Fatty acid Sodium nitroprusside Antioxidant enzymes Yield

Solute transport and geochemical modeling of the coastal quaternary aquifer, Delta Dahab Basin, South Sinai, Egypt

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Acta Geochimica 2024年第1期43卷 16-39页

作者： Amira Samy mustafa Eissa Seham Shahen moustafa m.Said Rabab m.Abou-shahaba Division of Water Resources and Arid Land Department of HydrogeochemistryDesert Research CenterCairoEgypt Egypt Desalination Research Center of Excellence Desert Research CenterCairoEgypt Center for Water Supply Studies S&E-Physical&Environmental SciencesTexas A&M University Corpus ChristiCorpus ChristiUSA Department of Chemistry Faculty of Science(Girls)Al-Azhar UniversityYousef Abbas StrNasr CityP.O.Box:11754CairoEgypt

The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The primary water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from 890to 8213 mg/L, with a mean value of 3417 mg/L. The dissolved major ions have been used to calculate the seawater mixing index(SWmI) using a linear equation that discriminates the groundwater mostly affected by water–rock interaction(SWmI 1>) and other samples mixed with Seawater(SWmI otopic composition of groundwater for specifically chosen groundwater samples ranges from-0.645‰ to +5.212‰ for δ^(18)o and from-9.582‰ to + 22.778‰ for δ^(2)H, where the seawater represented by a Red Sea water sample(δ^(18)o + 1.64‰-δ^(2)H + 9.80‰) and reject brine water are considerably enriched the isotopic groundwater values. The geochemical NETPATH model constrained by the dissolved significant ions, isotopes, and the rock aquifer forming minerals as phases indicate the mixing percent with the seawater ranges from 9% to 97% of seawater from 91% to 3% of original recharge water. According to the SEAWAT 3-D flow models, seawater has penetrated the Northeastern Dahab delta aquifer, with the intrusion zone extending1500 m inland. The salt dissolution, upwelling of saline water, recharge from the upstream mountain block, and seawater encroachment are the primary aspects contributing to the deterioration of groundwater quality. These findings may have significance for effective groundwater withdrawal management in arid locations worldwide with similar hydrogeological systems.

关键词： Groundwater geochemistry Seawater intrusion Solute transport SEAWAT

Vaccination effect on a stochastic epidemic model with healing and relapse

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International Journal of Biomathematics 2024年第1期17卷 29-59页

作者： m.m.Abdeslami L.Basri m.El Fatini I.Sekkak R.Taki Laboratory of Partial Differential Equations Spectral Algebra and Geometry Department of mathematics Faculty of Sciences Ibn Tofail UniversityBP 133KénitraMorocco Centre de Recherche en Sante Publique montréal(Québec)H3N 1X9 Canada Departement de Medecine Sociale et Preventive Ecole de SantéPublique de I'Universitéde Montreal 101Avenue du ParcMontréal(Quebec)H3N 1X9Canada EST Sidi Bennour Chouaib Doukkali UniversityEl JadidaMorocco

In this work,we consider a stochastic epidemic model with vaccination,healing and *** prove the existence and the uniqueness of the positive *** establish sufficient conditions for the extinction and the persistence in mean of the stochastic ***,we also establish sufficient conditions for the existence of ergodic stationary distribution to the model,which reveals that the infectious disease will *** graphical illustrations of the approximate solutions of the stochastic epidemic model have been performed.

关键词： Stochastic epidemic model with relapse and healing vaccination extinction persistence in mean markov semigroup stationary distribution

Large magnetocaloric effect and magnetic properties of EuRho3

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Journal of Rare Earths 2024年第9期42卷 1724-1729页

作者： m.Lassri m.Sajieddine A.Elouafi A.El Hachmi S.El ouahbi R.moubah Laboratory of Energy and materials Engineering (LGEm) University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) Institute of Applied Physics (IAP)-School of Industrial management (EmINES) Mohammed Ⅵ Polytechnic University National School of Applied Sciences (ENSA) University of Sultan Moulay Slimane Laboratory of mechanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of Radiation on matter and Instrumentation (LRmI) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Physics of Advanced materials and Thermic (LPmAT) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the structural,magnetic,and magnetocaloric properties of *** oxidation states of Eu and Rh ions were studied using X-ray photoelectron spectroscopy（XPS）.It is found that the Eu ions are mainly in the divalent oxidation state while the Rh ions have+4 ***3powders are found to be antiferromagnetic with a second order magnetic transition at Neel temperature（TN=2.9 K）.Analysis of the magnetic susceptibility versus temperature data in terms of the Curie=Weiss law:(χ=C/（T-θW）) for T>TN,yields θW=-3.1 K and effective magne tic moment ■,which is close to the theoretical value ■.The magnetic entropy change(-ΔSm),was determined by em ploying the thermodynam ic maxwell's *** μ0H=5 T and near TN,■ and relative cooling power（RCP） exhibit large values of 33.7 J/（kg·K） and 238 J/kg,*** large magnitude of-ΔSmand RCP show that the EuRho3compound could be a potential candidate to be used in cryogenic magnetic refrigeration.

关键词： Cryogenic magnetic refrigeration magnetic properties magnetocaloric effect Rare earths X-ray photoelectron spectroscopy

Growth of RB Population in the Conversion Phase of Chlamydia Life Cycle

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Communications on Applied mathematics and Computation 2024年第1期6卷 90-112页

作者： Frederic Y.m.Wan Department of mathematics University of CaliforniaIrvineCA92697-3875USA

Upon infecting a host cell,the reticulate body(RB)form of the Chlamydia bacteria simply proliferates by binary fission for an extended *** data show only RB units in the infected cells 20 hours post infection(hpi),spanning nearly half way through the development *** data collected every 4 hpi,conversion to the elementary body(EB)form begins abruptly at a rapid rate sometime around 24 *** modeling proliferation and conversion as simple birth and death processes,it has been shown that the optimal strategy for maximizing the total(mean)EB population at host cell lysis time is a bang-bang control qualitatively replicating the observed conversion ***,the simple birth and death model for the RB proliferation and conversion to EB deviates in a significant way from the available data on the evolution of the RB population after the onset of RB-to-EB *** working with a more refined model that takes into account a small size threshold eligibility requirement for conversion noted in the available data,we succeed in removing the deficiency of the previous models on the evolution of the RB population without affecting the optimal bang-bang conversion strategy.

关键词： Chlamydia Life cycle optimal control maximal infectious spread Specie competitive survival

Global prevalence and gender inequalities in at least 60 min of self-reported moderate-to-vigorous physical activity 1 or more days per week:An analysis with 707,616 adolescents

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Journal of Sport and Health Science 2024年第5期13卷 709-716页

作者： Raphael H.o.Araujo Andrúo.Werneck Clarice L.martins Luciana L.Barboza Rafael m.Tassitano Nicolas Aguilar-Farias Gilmar m.Jesus Robinson Ramírez-Véelez Riki Tesler Adewale L.oyeyemi Ellen C.m.Silva Robert G.Weaver mark S.Tremblay Javier Brazo-Sayavera Grégore I.mielke Danilo R.P.Silva Graduation Program in Health Sciences Londrina State University(UEL)Londrina 86057-970Brazil Center for Epidemiological Research in Nutrition and Health Department of NutritionSchool of Public HealthUniversidade de Sao Paulo(USP)Sao Paulo 01246-904Brazil Department of Physical Education Federal University of ParaıbaParaıba 58051-900Brazil Research Centre of Physical Activity Health and LeisureFaculty of SportsLaboratory for Integrative and Translational Research in Population Health(ITR)University of PortoPorto 4500Portugal Postgraduate Program in Physical Education University of BrasıliaBrasılia 70910-900Brazil Department of Kinesiology and Community Health University of Illinois at Urbana-ChampaignChampaignIL 61801-3841USA Department of Physical Education Sports and RecreationUniversidad de La FronteraTemuco 4680000Chile Department of Health State University of Feira de SantanaFeira de Santana 44036-900Brazil Navarrabiomed Hospital Universitario de Navarra(HUN)Navarra Institute for Health Research(IdiSNA)Universidad Publica de Navarra(UPNA)Pamplona 31006Spain Facultad de Ciencias de la Educacion Unidad Central del Valle del Cauca(UCEVA)TuluaValle del Cauca 763022Colombia Health management Department Faculty of Heath sciencesAriel UniversityAriel 40700Israel College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Arnold School of Public Health University of South CarolinaColumbiaSC 29208USA Healthy Active Living and obesity Research Group Children’s Hospital of Eastern Ontario Research InstituteOttawaON K1H 8L1Canada Department of Pediatrics University of OttawaOttawaON K1H 8L1Canada Department of Health Sciences Carleton UniversityOttawaON K1S 5B6Canada Department of Sports and Computer Science Universidad Pablo de Olavide(UPO)Seville 41013Spain Centro Universitario Regional Noreste Universidad de la RepublicaRivera 40000Uruguay School of Public Health The University of QueenslandBrisbaneQLD 4006Australia Department of Physical Education

Background:Guidelines recommend that adolescents should accumulate an average of 60 min per day of moderate-to-vigorous physical activity(mVPA).However,using only this cut-off could hide important *** instance,from a population-level point of view,increasing physical activity for those with no or low physical activity could provide more health benefits than increasing physical activity for those with intermediate ***,including a more sensitive cut-point of≥1 days per week could be an additional strategy for identifying those with low access/opportunities for physical activity ***,the current study aims to estimate the prevalence of≥60 min of mVPA≥1 days per week among adolescents globally,and to describe any relevant gender ***:We used representative datasets from 146 countries/territories collected between 2003 and *** was *** were grouped into younger(≤14 years old)and older(>14 years old)*** Poisson regression models were used to identify the relative differences in≥60 min of mVPA≥1 days per week between boys and girls,and random-effects meta-analysis models were used to identify the pooled *** were stratified by country and ***:Approximately 80%of both younger and older adolescents reported≥60 min of mVPA≥1 days per *** prevalence was≥94%in Europe and Central Asia and North America,while the estimates for the other regions wereof≥60 min of mVPA≥1 days per week was higher among boys than girls,with the largest differences occurring among the oldest adolescents(Prevalence ratio_(≤14y)=1.04(95%confidence interval(95%CI)):1.03-1.04)*** ratio_(>14y)=1.09(95%CI:1.08-1.10)).Conclusion:Approximately 8 out of 10 adolescents reported accumulating≥60 min of mVPA≥1 days per week,with notable differences between *** differences were observed in several countries,especially among the oldest *** fo

关键词： Global School-based Student Health Survey Health Behaviour Among School-aged Children survey Inequality Surveillance Youth