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加速的脊柱MRI的深度学习重建：互换性前瞻性分析

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国际医学放射学杂志 2023年第3期 353-353页

作者： H.Almansour j.herrmann S.Gassenmaier S.Afat j.jacoby G.Koerzdoerfer 刘小草

摘要基于深度学习（DL）的MRI重建可以减少快速自旋回波（TSE）采集的检查时间，但是需要在实际的临床场景中对基于DL的快速获得的、采样不足的脊柱MRI重建进行

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Older Adult Compendium of Physical Activities:Energy costs of human activities in adults aged 60 and older

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journal of Sport and Health Science 2024年第1期13卷 13-17,F0003页

作者： Erik A.Willis Stephen D.herrmann Mary Hastert Chelsea L.Kracht Tiago V.Barreira john M.Schuna jr. Zhenghua Cai Minghui Quan Scott A.Conger Wendy j.Brown Barbara E.Ainsworth Center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA Kansas Center for Metabolism and Obesity Research The University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Clinical Science Division Pennington Biomedical Research CenterBaton RougeLA 70808USA Exercise Science Department Syracuse UniversitySyracuseNY 13244USA School of Exercise&Sport Science Oregon State UniversityCorvallisOR 97331USA School of Exercise and Health Shanghai University of SportShanghai 200438China Department of Kinesiology Boise State UniversityBoiseID 83725USA School of Human Movement and Nutrition Sciences The University of QueenslandSt.LuciaQLD 4072Australia Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4229Australia College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA

Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MET)values were obtained from a systematic search of studies published in 4 sport and exercise databases(PubMed,Embase,SPORTDiscus(EBSCOhost),and Scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older *** values were computed as the oxygen cost(VO_(2),mL/kg/min)during PA divided by 2.7 m L/kg/min(MET_(60+))to account for the lower resting metabolic rate in older ***:We identified 68 articles and extracted energy expenditure data on 427 *** these,we derived 99 unique Specific Activity codes with corresponding MET_(60+)values for older *** developed a website to present the OA Compendium MET_(60+)values:https://***:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older *** is an accessible resource that will allow researchers,educators,and practitioners to find MET_(60+)values for older adults for use in PA research and practice.

关键词： Energy expenditure Exercise MET Older adults

用18F-FDGPET/CT检测1型神经纤维瘤病中的恶性周围神经鞘瘤时,肿瘤-肝摄取比值优于SUVmax阈值

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国际医学放射学杂志 2014年第2期 198-198页

作者： j.Salamon S.Veldhoen I.Apostolova P.Bannas j.Yamamura j.herrmann 余晓 Department of Diagnostic and Interventional Radiology University Hospital Hamburg-Eppendorf Martinistr5220246 HamburgGermany

目的应用18F-FDG PET/CT测量病变与参考组织标准化示踪剂积聚的比值,寻找1型神经纤维瘤病(NF1)中的周围神经鞘瘤(PNST)的比值规律,并与公认的最大标准

关键词：神经纤维瘤病 1型神经纤维瘤病恶性周围神经鞘瘤比率正电子发射体层成像

小儿肝移植术后跨肝包膜动脉血管生成表明移植失败

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国际医学放射学杂志 2012年第1期 76-76页

作者： j.herrmann C.M.junge M.Burdelski R.Ganschow S.Scheibner K.U.Petersen 管宇 Department of Pediatric Radiology University Medical Center Hamburg-EppendorfMartinistrasse 5220246 HamburgGermany

目的通过多普勒超声(US)诊断患儿肝移植术后跨肝包膜动脉血管生成,并评估其发生率、潜在的原因及与临床预后的相关性。材料与方法本项研究获得当地伦理委员会批准并免除了病人知情同意。回顾性分析2000年1月—2003年12月期间接受肝移植... 详细信息

目的通过多普勒超声(US)诊断患儿肝移植术后跨肝包膜动脉血管生成,并评估其发生率、潜在的原因及与临床预后的相关性。材料与方法本项研究获得当地伦理委员会批准并免除了病人知情同意。回顾性分析2000年1月—2003年12月期间接受肝移植的所有患儿。按照一个预设的前瞻性

关键词：肝包膜新生血管肝移植术后动脉血管

Decomposition dynamics of coarse woody debris of three important central European tree species

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Forest Ecosystems 2015年第4期2卷 339-352页

作者： Steffen herrmann Tiemo Kahl jürgen Bauhus Institute of Forest Sciences Faculty of Environment and Natural ResourcesUniversity of Freiburg Swiss Federal Research Institute WSL

Background： Coarse woody debris （CWD） is an important element of forest structure that needs to be considered when managing forests for biodiversity, carbon storage or bioenergy. To manage it effectively dynamics of CWD decomposition should be known. Methods： Using a chronosequence approach, we assessed the decomposition rates of downed CWD of Fagus sylvatica, Picea obies and Pinus sylvestfis, which was sampled from three different years of tree fall and three different initial diameter classes （〉10 - ≤20 cm, 〉20 - ≤40 cm, 〉40 cm）. Samples originating from wind throws in 1999 were collected along a temperature and precipitation gradient. Based on the decay class and associated wood densities, log volumes were converted into CWD mass and C content. Log fragmentation was assessed over one year for log segments of intermediate diameters （〉20 - 40 cm） after 8 and 18 years of decomposition. Results： Significantly higher decomposition constants （k） were found in logs of F. sylvotica （0.054 year^-1） than in P. abies （0.033 year^-1） and P. sylvestris （0.032 year^-1）. However, mass loss of P. sylvestris occurred mainly in sapwood and hence k for the whole wood may be overestimated. Decomposition rates generally decreased with increasing log diameter class except for smaller dimensions in P. obies. About 74 % of the variation in mass remaining could be explained by decomposition time （27 %）, tree species （11%）, diameter （17 %）, the interactive effects between tree species and diameter （4 %） as well as between decomposition time and tree species （3 %） and a random factor （site and tree; 9.5 %）, whereas temperature explained only 2 %. Wood fragmentation may play a more important role than previously thought. Here, between 14 % and 30 % of the decomposition rates （for the first 18 years） were attributable to this process. Carbon （C） density （mgC· cm ^-3）, which was initially highest for F. sylvatico, followed by P. sylvestris and P. obies, decreased with increasing decay stage t

关键词： Dead wood Carbon Decay rate Beech Spruce Pine

Modeling slow deformation of polygonal particles using DEM

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Particuology 2008年第6期6卷 506-514页

作者： Andrés A. Pea Pedro G. Lind Hans j. herrmann Institute for Computational Physics Universitt Stuttgart Computational Physics IfB HIF E12 ETH Hnggerberg CH-8093 Zrich Switzerland Departamento de Física Universidade Federal do Ceará

We introduce two improvements in the numerical scheme to simulate collision and slow shearing of irregular particles. First, we propose an alternative approach based on simple relations to compute the frictional contact forces. The approach improves efficiency and accuracy of the Discrete Element Method （DEM） when modeling the dynamics of the granular packing. We determine the proper upper limit for the integration step in the standard numerical scheme using a wide range of material parameters. To this end, we study the kinetic energy decay in a stress controlled test between two particles. Second, we show that the usual way of defining the contact plane between two polygonal particles is, in general, not unique which leads to discontinuities in the direction of the contact plane while particles move. To solve this drawback, we introduce an accurate definition for the contact plane based on the shape of the overlap area between touching particles, which evolves continuously in time.

关键词： Granular media Discrete element method Slow deformation Contact forces

Nutrient retention and release in coarse woody debris of three important central European tree species and the use of NIRS to determine deadwood chemical properties

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Forest Ecosystems 2018年第3期5卷 296-310页

作者： Steffen herrmann jurgen Bauhus Faculty of Environment and Natural Resources University of Freiburg Tennenbacherstr.4D-79106Freiburg i.Br.Germany Thunen Institute of Forest Ecosystems Alfred-M611er-Strabe 1Haus41/4216225EberswaldeGermany

Background: Coarse woody debris(CWD) is very important for forest ecosystems, particularly for biodiversity and carbon storage. Its relevance as a possible reservoir and source of nutrients is less clear, especially in central ***: Based on a chronosequence of known ages of logs, we analyzed the nutrients stored in CWD of Fagus sylvatica, Picea abies, and Pinus sylvestris at different sites in Germany. To quantify nutrient concentrations, we assessed the use of Near Infrared Reflectance Spectroscopy(NIRS) to determine the chemical properties of ***: NIRS models were suitable to predict concentrations of C, N, P, lignin and extractives. Concentrations of most nutrients increased with mass loss, with the exception of potassium, which decreased for beech and pine and remained relatively constant for spruce. The highest nutrient concentrations(N, P, S, Ca and Mn, except Mg and K) were generally observed in highly decomposed spruce logs. The net effect of decreasing CWD mass and increasing nutrient concentrations was either a decreasing(N, P and K in beech; P, Mg, K and Mn in pine), constant(S, Ca and Mg in beech; N, S and Ca in pine) or increasing amount of nutrients(N, P, S and Ca in spruce; Mn in beech) in the logsover the course of decomposition. The C/N ratio decreased for all tree species, most markedly for spruce from ca. 1000 at the beginning of the decomposition process to 180 at 36 years. The N/P ratio converged to a value of about 30 forall three species. Lignin concentrations increased for spruce and beech and remained constant for ***: Our results indicate that most nutrients remain in CWD for long periods. Nutrients may be used and cycled by microorganisms within CWD, but with the exception of P(in beech), Mg(in pine) and K(in beech and pine), there appears to be little net nutrient export until two thirds of the mass is lost. Instead, N, P, S and Ca were accumulated in spruce logs, indicating that CWD became a net sink rathe

关键词： CWD NIRS Decay Carbon F.sylvatica P.abies P.sylvestris

Thulium：YAG VapoEnucleation of the prostate in large glands： a prospective comparison using 70- and 120-W 2-μm lasers

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Asian journal of Andrology 2012年第2期14卷 325-329页

作者： Christopher Netsch Thorsten Bach Thomas RW herrmann Andreas j Gross Department of Urology Asklepios Hospital BarmbekHamburg 22291Germany Department of Urology MHH Medical School of HannoverHannover 30625Germany

This study compared the efficacy of 70- and 120-w 2-μm thulium：YAG VapoEnucleation of the prostate （ThuVEP） for patients with benign prostatic obstruction （BPO）. A prospective analysis of 84 patients with symptomatic BPO and prostatic enlargement （t〉 60 ml） who underwent either 70-w （n=44） or 120-w ThuVEP （n=40） non-randomly was carried out. Patient demographics and perioperative and 12-month follow-up data were analysed. The mean prostate volume was 79.90---27.49 ml in patients who had received 70-w ThuVEP, which was less than in those who had received 120-w ThuVEP （88.53＋-25.10; P=0.033）. The mean enucleation （resected weight/laser time, 2.16±1.21 g min-1 vs. 1.23±0.60 g min-1; P=-0.013）, operation efficiency （resected weight/total operation time, 0.76±0.35 g min-1 vs. 0.42＋-0.27 g min-1; P=-0.000） and percentage of resected tissue （66.93%±22.79% vs. 45.41%±23.33%; P=-0.000） were higher with 120-w treatment compared to 70-w ThuVEP. One patient （1.2% of total patients）（in the 120-w group） required a blood transfusion postoperatively. Sixty-one patients （73%） were available for review at the 12-month follow-up time point. The quality of life （QoL）, International Prostate Symptom Score （IPSS）, maximum urinary flow rate （Qmax）, postvoiding residual urine （PVR） and prostate volume improved significantly after treatment （P≤ 0.035） and were not significantly different between those treated with the different devices （70- and 120-w）. The median prostate volume reduction was 81.70% and 82.19% with 70- and 120-w ThuVEP, respectively. The incidence of complications was low and did not differ between groups treated with the different devices. Two patients （2.4%）（one per group） had a bladder neck contracture at the follow-up. ThuVEP is a safe and efficacious procedure for the treatment of symptomatic BPO. The incidence of complications was low with both devices. The 120-w thulium：YAG device enhances the effectiveness of Th,VEP with reeard to the oercentaee of resected tissue

关键词： benign prostatic obstruction laser prostate Revolix Tm:YAG ThuVEP VapoEnucleation

Micromechanical investigation of granular ratcheting using a discrete model of polygonal particles

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Particuology 2008年第6期6卷 390-403页

作者： Fernando Alonso-Marroquín Hans B. Mhlhaus Hans j. herrmann Earth Systems Science Computational Centre & School of Physical Sciences The University of Queensland Earth Systems Science Computational Centre The University of Queensland Institut fr Baustoffe ETH-HenggerbergZrich

We use a two-dimensional model of polygonal particles to investigate granular ratcheting. Ratcheting is a long-term response of granular materials under cyclic loading, where the same amount of permanent deformation is accumulated after each cycle. We report on ratcheting for low frequencies and extremely small loading amplitudes. The evolution of the sub-network of sliding contacts allows us to understand the micromechanics of ratcheting. We show that the contact network evolves almost periodically under cyclic loading as the sub-network of the sliding contacts reaches different stages of anisotropy in each cycle. Sliding contacts lead to a monotonic accumulation of permanent deformation per cycle in each particle. The distribution of these deformations appears to be correlated in form of vortices inside the granular assembly.

关键词： Granular systems Dynamics and kinematics of rigid bodies Molecular dynamics methods