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Journal of Sport and Health Science 2016年第2期5卷 145-150页

作者： Jakob Tarp Jan christian Br?nd Lars Bo Andersen niels christian m?ller Karsten Froberg Anders Gr?ntved Research Unit for Exercise Epidemiology Centre of Research in Childhood Health Department of Sport Science and Clinical BiomechanicsUniversity of Southern Denmark Department of Sports medicine Norwegian School of Sport Sciences

The long-term effects of physical activity （PA） or sedentary behavior on cardiovascular health in young people are not well understood. In this study, we use a narrative format to review the evidence for a prospective association with adiposity and other well-established biological cardiovascular risk factors in healthy young people, considering only studies with at least 2 years of follow-up. PA appears to elicit a long-term beneficial effect on adiposity and particularly markers of cardiovascular health. With adiposity, however, a few studies also reported that higher levels of PA were associated with higher levels of adiposity. Time spent sedentary does not appear to be related to adiposity or markers of cardiovascular health independent of PA. We then discuss the uncertainties in the underlying causal chain and consider a number of alternative modeling strategies, which could improve our understanding of the relationship in future studies. Finally, we consider the current methodology for assessing PA and sedentary time.

关键词： Adiposity Adolescents Cardiovascular health Children Long-term metabolic syndrome score

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

Development of an active-site titrant for SARS-CoV-2 main protease as an indispensable tool for evaluating enzyme kinetics

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2349-2357页

作者： Rabea Voget Julian Breidenbach Tobias Claff Alexandra Hingst Katharina Sylvester christian Steinebach Lan Phuong Vu Renato H.Weiße Ulrike Bartz Norbert Sträter Christa E.müller michael Gütschow Pharmaceutical Institute Pharmaceutical&Medicinal ChemistryUniversity of BonnBonn 53121Germany Institute of Bioanalytical Chemistry Center for Biotechnology and BiomedicineLeipzig UniversityLeipzig 04103Germany Department of Natural Sciences University of Applied Sciences Bonn-Rhein-SiegRheinbach 53359Germany

A titrant for the SARS-CoV-2 main protease(m^(pro))was developed that enables,for the first time,the exact determination of the concentration of the enzymatically active m^(pro) by active-site *** covalent binding mode of the tetrapeptidic titrant was elucidated by the determination of the crystal structure of the enzyme–titrant *** fluorogenic substrates of m^(pro),including a prototypical,internally quenched Dabcyl-EDANS peptide,were compared in terms of solubility under typical assay *** exploiting the new titrant,key kinetic parameters for the m^(pro)-catalyzed cleavage of these substrates were determined.

关键词： COVID-19 SARS-CoV-2 main protease Peptide nitriles Fluorogenic substrates Active-site titration X-ray crystallography Inner filter effect

Limb symmetry index in competitive alpine ski racers:Reference values and injury risk identification according to age-related performance levels

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Journal of Sport and Health Science 2018年第4期7卷 405-415页

作者： Lisa Steidl-müller Carolin Hildebrandt Erich müiller christian Fink christian Raschner Department of Sport Science University oflnnsbruekInnsbruck 6020Austria Department of Sport Science and Kinesiology University of SalzburgSalzburg 5400Austria Research Unit for Orthopedic Sports medicine and Injury Prevention Institute of Psychology（ISAG）The Health ＆ Life Sciences University（UMIT）Innsbruck 6020Austria Gelenkpunkt-Sports and Joint Surgery Innsbruck 6020Austria Corresponding author.E-mail address：lisa.steidl-mueller@uibk.ac.at

Purpose： The aims of this study were to assess differences of limb symmetry index （LSI） in strength- and coordination-related tasks between high-level, competitive, noninjured ski racers of different age-related performance levels and to prospectively assess limb differences as a possible risk factor for traumatic and overuse injury in youth ski racers. methods： The study （Study 1） included 285 high-level competitive ski racers （125 females, 160 males） of 3 age-related performance levels and based on the school system： 95 youth （10-14 years, secondary modem school）, 107 adolescent （15-19 years, grammar school）, and 83 elite athletes （20-34 years）. To investigate the second aim （Study 2）, 67 of the 95 youth athletes were included and any traumatic or overuse injuries were prospectively recorded over 2 seasons. All athletes performed 4 unilateral tests （strength related： one-leg counter movement jump （OL-CmJ） and one-leg isometric/isokinetic press strength test （OL-ILS）; coordination related： one-leg stability test （OL-ST） and one-leg speedy jump test （OL-SJ））. The LSI was calculated by dividing the dominant leg by the nondominant leg and multiplying by 100. Kruskal-Wallis H tests and binary logistic regression analyses were conducted. Results： There were significant differences between the LSI of the 3 age-related performance-level groups only in the strength-related tests： the OL-CmJ （X^2（2, 285） = 9.09; p = 0.01） and the OL-ILS （X^2（2,285） = 14.79; p 〈 0.01）. The LSI for OL-ILS was found to be a significant risk factor for traumatic injury in youth ski racers （Wald = 7.08; p 〈 0.01）. No significant risk factors were found for overuse injuries. Conclusion： Younger athletes display slightly greater LSI values only in the strength-related tests. The cut-off value of limb differences of 〈 10% for return to sport decisions seems to be appropriate for elite athletes, but for youth and adolescent athletes it has to be critically discussed. It seems to be necessary to defi

关键词： Age-related performance levels Alpine ski racing Injury risk Limb differences Youth athletes

Training load characteristics and injury and illness risk identification in elite youth ski racing:A prospective study

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Journal of Sport and Health Science 2021年第2期10卷 230-236页

作者： Carolin Hildebrandt Renate Oberhoffer christian Raschner Erich muller christian Fink Lisa Steidl-muller Department of Sport Science University of InnsbruckInnsbruck 6020Austria Department of Sport and Health Science Preventative PediatricsTechnical University of MunichMunich 80992Germany Department of Sport Science and Kinesiology University of SalzburgSalzburg 5400Austria GelenkpunktSports and Joint Surgery Innsbruck 6020Austria

Purpose:The study aimed to investigate the role of training load characteristics and injury and illness risk in youth ski ***:The training load characteristics as well as traumatic injuries,overuse injuries,and illnesses of 91 elite youth ski racers(age=12.1±1.3 years,mean±SD)were prospectively recorded over a period of 1 season by using a sport-specific online *** linear regression analyses were performed to monitor the influence of training load on injuries and *** in mean training load characteristics between preseason,in-season,and post-season were calculated using multivariate analyses of ***:Differences were discovered in the number of weekly training sessions(p=0.005)between pre-season(4.97±1.57)and post-season(3.24±0.71),in the mean training volume(p=0.022)between in-season(865.8±197.8 min)and post-season(497.0±225.5 min)and in the mean weekly training intensity(Index)(p=0.012)between in-season(11.7±1.8)and post-season(8.9±1.7).A total of 185 medical problems were reported(41 traumatic injuries,12 overuse injuries,and 132 illnesses).The weekly training volume and training intensity was not a significant risk factor for injuries(p>0.05).Training intensity was found to be a significant risk factor for illnesses in the same week(β=0.348;p=0.044;R^(2)=0.121)and training volume represents a risk factor for illnesses in the following week(β=0.397;p=0.027;R^(2)=0.157).Conclusion:A higher training intensity and volume were associated with increased illnesses,but not with a higher risk of *** training and ensuring appropriate progression of training load between weeks may decrease incidents of illness in-season.

关键词： Health problems Injury and illness prevention Training load Youth ski racing

Dynamic magnetic resonance defecography in 10 asymptomatic volunteers

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World Journal of Gastroenterology 2012年第46期18卷 6836-6842页

作者： Andreas G Schreyer christian Paetzel Alois Fürst Lena m Dendl Elisabeth Hutzel René müller-Wille Philipp Wiggermann Stephan Schleder christian Stroszczynski Patrick Hoffstetter Department of Radiology University Medical Center Regensburg Department of Radiology Weiden Hospital Department of Surgery St. Josef Hospital

AIm: Evaluation of the wide range of normal findings in asymptomatic women undergoing dynamic magnetic resonance (mR) defecography. mETHODS: mR defecography of 10 healthy female volunteers (median age: 31 years) without previous pregnancies or history of surgery were evaluated. The rectum was filled with 180 mL gadolinium ultrasound gel mixture. mR defecography was performed in the supine position. The pelvic floor was visualized with a dynamic T2-weighted sagittal plane where all relevant pelvic floor organs were acquired during defecation. The volunteers were instructed to relax and then to perform straining maneuvers to empty the rectum. The pubococcygeal line (PCGL) was used as the line of reference. The movement of pelvic floor organs was measured as the vertical distance to this reference line. Data were recorded in the resting position as well as during the defecation process with maximal straining. Examinations were performed and evaluated by two experienced abdominal radiologists without knowledge of patient history. RESULTS: Average position of the anorectal junction was located at -5.3 mm at rest and -29.9 mm during straining. The anorectal angle widened significantly from 93° at rest to 109° during defecation. A rectocele was diagnosed in eight out of 10 volunteers showing an average diameter of 25.9 mm. The bladder base was located at a position of +23 mm at rest and descended to -8.1 mm during defecation in relation to the PCGL. The bladder base moved below the PCGL in six out of 10 volunteers, which was formally defined as a cystocele. The uterocervical junction was located at an average level of +43.1 mm at rest and at +7.9 mm during straining. The uterocervical junction of three volunteers fell below the PCGL; described formally as uterocervical prolapse. CONCLUSION: Based on the range of standard values in asymptomatic volunteers, mR defecography values for pathological changes have to be re-evaluated.

关键词： magnetic resonance imaging Defecography Standard values

Anemia and long-term outcome in adjuvant and neoadjuvant radiochemotherapy of stage Ⅱ and Ⅲ rectal adenocarcinoma:The Freiburg experience(1989-2002)

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World Journal of Gastroenterology 2006年第12期12卷 1849-1858页

作者： christian Weissenberger Geissler michael Otto Florian Barke Annette Henne Karl von Plehn Georg Rein Alex müller Christine Bartelt Susanne Henke michael Department of Radiotherapy University Hospital of Freiburg79106 FreiburgGermany Department Oncology Gastroenterology and Internal MedicineStidtische Kliniken Esslingen73730 Esslingen a.N.Germany Department of Internal medicine I Division of OncologyUniversity Hospital of Freiburg79106 FreiburgGermany

AIm： To evaluate the long-term outcome of standard 5-FU based adjuvant or neoadjuvant radiochemotherapy and to identify the predictive factors, especially anemia before and after radiotherapy as well as hemoglobin increase or decrease during radiotherapy. mETHODS： Two hundred and eighty-six patients with Union International Contre Cancer （UICC） stage Ⅱ and Ⅲ rectal adenocarcinomas, who underwent resection by conventional surgical techniques （low anterior or abdominoperineal resection）, received either postoperative （n = 233） or preoperative （n = 53） radiochemotherapy from January 1989 until July 2002. Overall survival （OAS）, cancer-specific survival （CSS）, disease-free survival （DFS）, local-relapse-free （LRS） and distant-relapse-free survival （DRS） were evaluated using Kaplan-meier, Log-rank test and Cox＇s proportional hazards as statistical methods. multivariate analysis was used to identify prognostic factors. median follow-up time was 8 years. RESULTS： Anemia before radiochemotherapy was an independent prognostic factor for improved DFS （risk ratio 0.76, P= 0.04） as well as stage, grading, R status （free radial margins）, type of surgery, carcinoembryonic antigen （CEA） levels, and gender. The univariate analysis revealed that anemia was associated with impaired LRS（better local control） but with improved DFS. In contrast, hemoglobin decrease during radiotherapy was an independent risk factor for DFS （risk ratio 1.97, P= 0.04）. During radiotherapy, only 30.8% of R0-resected patients suffered from hemoglobin decrease compared to 55.6% if R1/2 resection was performed （P= 0.04）. The 5-year OAS, CSS, DFS, LRS and DRS were 47.0%, 60.0%, 41.4%, 67.2%, and 84.3%, respectively. Significant differences between preoperative and postoperative radiochemotherapy were not found. CONCLUSION ： Anemia before radiochemotherapy and hemoglobin decrease during radiotherapy have no predictive value for the outcome of rectal cancer. Stage, grading, R status （free radial margins）, t

关键词： Rectal cancer Adjuvant radiotherapy Adjuvant radiochemotherapy Anemia Procjnostic factor

Highly insulating thermoplastic blends comprising a styrenic copolymer for direct‐current power cable insulation

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High Voltage 2022年第2期7卷 251-259页

作者： Yingwei Ouyang Amir masoud Pourrahimi IdaÖstergren marcus mellqvist JakobÅnevall Azadeh Soroudi Anja Lund Xiangdong Xu Thomas Gkourmpis Per‐Ola Hagstrand christian müller Department of Chemistry and Chemical Engineering Chalmers University of TechnologyGöteborgSweden Department of Electrical Engineering Chalmers University of TechnologyGöteborgSweden Innovation&Technology Borealis ABStenungsundSweden

The impact of the composition of blends comprising low‐density polyethylene(LDPE),isotactic polypropylene(PP)and a styrenic copolymer additive on the thermomechanical properties as well as the direct‐current(DC)electrical and thermal conductivity is *** presence of 5 weight percent(wt%)of the styrenic copolymer strongly reduces the amount of PP that is needed to enhance the storage modulus above the melting temperature of LDPE from 40 to 24 wt%.At the same time,the copolymer improves the consistency of the thermomechanical properties of the resulting ternary *** both the DC electrical and thermal conductivity strongly decrease with PP content,the addition of the styrenic copolymer appears to have little influence on either ***,PP in combination with small amounts of a styrenic copolymer not only allows to reinforce LDPE at elevated temperatures but also functions as an electrical conductivity‐reducing additive,which makes such thermoplastic ternary formulations possible candidates for the insulation of high‐voltage power cables.

关键词： property. blends copolymer

Influence of rolling friction on single spout fluidized bed simulation

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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

Polymer Analyses for an Adapted Process Design of the Pipe-Extrusion of Polyetherimide

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materials Sciences and Applications 2018年第7期9卷 614-624页

作者： michael Stegelmann michael müller Anja Winkler Alexander Liebsch niels modler Institute of Lightweight Engineering and Polymer Technology (ILK) TU Dresden Dresden Germany

Over the last years, the use of high performance thermoplastic materials increased significantly especially in aviation applications. Thus, the processing of these high temperature polymers became more and more interesting. Especially, the groups of polymers like polyphenylene sulfide (PPS), polyether ether ketone (PEEK) or polyetherimide (PEI) are in the focus of recent developments and investigations. These materials show excellent thermal, mechanical and chemical properties while processing remains still challenging. Especially the influence of processing temperatures, temperature depending viscosities, the specific heat capacities and the thermal expansion show a high impact to the quality of the produced parts, e.g. degradation and dimensionally stability. Thus, this paper shows experimental characterizations in regard to the processing of PEI by pipe extrusion processes. In this context, a suitable methodology for the determination of appropriate process parameters is shown, which includes the comprehensive determination of temperature dependent thermal, thermomechanical and degradation properties of specific PEI extrusion materials.

关键词： High Temperature Polymers Thermal Analysis Extrusion Process monitoring