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Predictability of sediment transport in the Yellow River using selected transport formulas

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International Journal of Sediment Research 2008年第4期23卷 283-298页

作者： D.S.van maren Postdoctoral Fellow Delft University of Technology Faculty of Civil Engineering and Geosciences the Netherlands and WL | Delft HydraulicsPO Box 177 2600 MH Delft The Netherlands.

This paper evaluates the applicability of the sediment transport methods developed by Engelund and Hansen, Ackers and White, Yang et al., and van Rijn, together with the Wuhan methods developed in China, to the Yellow River, which has highly concentrated and fine-grained sediment. The sediment data includes over 1000 observations from the Yellow River, 32 sets of data from a canal, and 266 sets of data from laboratory flumes. The best predictions were obtained by the Yang 1996 method, the Wuhan method, and the modified Wuhan method by Wu and Long, while reasonably good predictions were also provided by the van Rijn 2004 method. The Engelund and Hansen, the Ackers and White, and the van Rijn 1984 methods in their original forms are not applicable to the Yellow River. The predicted results for total load concentrations were as good as for bed-material concentrations, even though the total load includes a large portion of wash load.

关键词： Yellow River Sediment transport High concentration Fine sediment

Object-oriented Modeling for Planning and Control of Multi-energy Systems

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CSEE Journal of Power and Energy Systems 2019年第3期5卷 355-364页

作者： Stefan Bschorer maren Kuschke Kai Strunz the Chair of Sustainable Electric Networks and Sources of Energy School of Electrical Engineering and Computer ScienceTechnische Universitat Berlin10623 BerlinGermany

Multi-energy systems(MES)involving networks of different energy carriers can support the balancing of fluctuating renewable generation by co-ordinated joint *** this paper,an object-oriented modeling methodology for planning and operations control of MES based on nodal analysis is *** framework provides the modularity to simulate scenarios with varying network *** on object-oriented programming,classes are formed with regard to common attributes of the network *** instances of classes represent physical network elements,such as buses,lines,and power conversion *** models of the individual network elements involve adjustable and flexible *** is especially advantageous for scenarios with operatingpoint-dependent *** overall framework makes use of a uniform description of the model parameters across the diverse energy ***,the methodology is particularly suited for the analysis of *** applicability of the modeling framework is demonstrated by two use cases involving a technology campus in Berlin.

关键词： Control of multi-energy systems cooling network demand-side management electric network heating network object-oriented programming operations control of multi-energy systems planning of multi-energy systems smart grids

Leaves of Field-Grown Mastic Trees Suffer Oxidative Stress at the Two Extremes of their Lifespan

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Journal of Integrative Plant Biology 2012年第8期54卷 584-594页

作者： Marta Juvany maren Müller Sergi Munn-Bosch Departament de Biologia Vegetal Facultat de BiologiaUniversitat de BarcelonaAvinguda Diagonal643E-08028 BarcelonaSpain

Leaf senescence is a complex phenomenon occurring in all plant species, but it is still poorly understood in plants grown in Mediterranean field conditions and well-adapted to harsh climatic conditions. To better understand the physiological processes underlying leaf senescence in mastic trees （Pistacia lentiscus L.）, we evaluated leaf growth, water and N content, photosystem II （PSII） photochemistry, lipid peroxidation and levels of photosynthetic pigments, antioxidants, abscisic acid, and salicylic acid and jasmonic acid during the complete leaf lifespan, from early expansion to late senescence in relation to natural climatic conditions in the field. While mature leaves suffered from water and N deficit during late spring and summer, both young （emerging） and old （senescing） leaves were most sensitive to photo- oxidative stress, as indicated by reductions in the Fv/Fm ratio and enhanced lipid peroxidation during late autumn and winter. Reductions in the FvlFm ratio were associated with low ^-tocopherol （vitamin E） levels, while very old, senescing leaves additionally showed severe anthocyanin losses. We have concluded that both young （emerging） and old （senescing） leaves suffer oxidative stress in mastic trees, which may be linked in part to suboptimal temperatures during late autumn and winter as well as to low vitamin E levels.

关键词： Leaf senescence lentisc (Pistacea lentiscus L.) oxidative stress phytohormones seasonal effects.

Properties of spin-orbit-coupled Bose-Einstein condensates

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Frontiers of physics 2016年第3期11卷 1-28页

作者： Yongping Zhang maren Elizabeth Mossman Thomas Buschl Peter Engels Chuanwei Zhang 1 Quantum Systems Unit Okinawa Institute of Science and Technology Graduate University Onna Okinawa 904-0495 Japan Department of Physics and Astronomy Washington State University Pullman WA 99164 USA Department of Physics The University of Texas at Dallas Richardson TX 75080 USA

The experimental and theoretical research of spin-orbit-coupled ultracold atomic gases has advanced and expanded rapidly in recent years. Here, we review some of the progress that either was pioneered by our own work, has helped to lay the foundation, or has developed new and relevant techniques. Af- ter examining the experimental accessibility of all relevant spin-orbit coupling parameters, we discuss the fundamental properties and general applications of spin-orbit-coupled Bose-Einstein condensates （BECs） over a wide range of physical situations. For the harmonically trapped case, we show that the ground state phase transition is a Dicke-type process and that spin-orbit-coupled BECs provide a unique platform to simulate and study the Dicke model and Dicke phase transitions. For a homo- geneous BEC, we discuss the collective excitations, which have been observed experimentally using Bragg spectroscopy. They feature a roton-like minimum, the softening of which provides a potential mechanism to understand the ~round state phase transition. On the other hand, if the collective dy- namics are excited by a sudden quenching of the spin-orbit coupling parameters, we show that the resulting collective dynamics can be related to the famous Zitterbewegung in the relativistic realm. Finally, we discuss the case of a BEC loaded into a periodic optical potential. Here, the spin-orbit coupling generates isolated fiat bands within the lowest Bloch bands whereas the nonlinearity of the system leads to dynamical instabilities of these Bloch waves. The experimental verification of this instability illustrates the lack of Galilean invariance in the system.

关键词： atomic Bose-Einstein condensate spin orbit coupling collective excitations optical lattice

Tree regeneration in gap-understory mosaics in a subtropical Shorea robusta(Sal) forest

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Journal of Forestry Research 2019年第6期30卷 2061-2068页

作者： L.N.Sharma K.B.Shrestha I.E.maren Forest Action Nepal GPO-12207 LalitpurNepal Department of Biological Sciences University of BergenThormoensgate 53B5007 BergenNorway

Spatial variation in tree-regeneration density is attributed to the specialization of tree species to light availability for germination and *** availability,in turn,varies across the gap-understorey *** gaps provide an important habitat for the regeneration of tree species that would otherwise be suppressed in the *** subtropical forests,there is still a knowledge-gap relating to how canopy disturbances influence tree-regeneration patterns at local scale,and if they disproportionately favor regeneration of certain *** aim to analyze whether canopy gaps promote tree regeneration,and tree species are specialized to gaps or understory for germination and *** sampled vegetation in 128 plots(0.01 ha),equally distributed in gaps and below canopy,in two subtropical Shorea robusta Gaertn.(Sal)forests in Nepal,recording the number of tree seedlings and saplings in each *** compared the regeneration density of seedlings and saplings separately between gaps and the *** mean densities of seedlings and saplings were higher in the gaps at both sites;although there was no difference in the seedling density of the majority of the species between the *** species were confined to either gap or understorey at the seedling *** conclude that gaps are not critical for the germination of tree species in Sal forests but these are an important habitat for enabling seedlings to survive into *** classification of trees into regeneration guilds mainly based on germination does not apply to the majority of tree species in subtropical Sal *** results reaffirm that gap creation promotes tree regeneration by favouring seedling survival and growth and can influence forest management for conservation,as well as for plantations.

关键词： Canopy-gap Density Regeneration Saplings Seedlings Shade tolerance

Robotic surgery and liver transplantation:A single-center experience of 501 robotic donor hepatectomies

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Hepatobiliary & Pancreatic Diseases International 2022年第4期21卷 334-339页

作者： maren Schulze Yasser Elsheikh Markus Ulrich Boehnert Yasir Alnemary Saleh Alabbad Dieter Clemens Broering Organ Transplant Center of Excellence King Faisal Specialist Hospital&Research CentreP.O.Box 3354Riyadh 11211Saudi Arabia

Background:Over the past two decades robotic surgery has been introduced to many areas including liver *** liver surgery is an alternative minimally invasive ***,moving on to the complexity of living donor hepatectomies,the advantages of robotic versus laparoscopic approach have convinced us to establish the robotic platform as a standard for living donor ***:From November 2018 to January 2022,501 fully robotic donor hepatectomies,including 177 left lateral donor lobes,112 full left lobes and 212 full right lobes were *** were donated to 296 adult recipients and 205 pediatric *** age,sex,body weight,body mass index(BMI),graft weight,graft to body weight ratio(GBWR),operative time,blood loss,first warm ischemic time,pain score,length of intensive care unit(ICU)stay and hospital stay,and complications were retrospectively analyzed based on a prospectively kept *** were evaluated for graft and patient survival,age,sex,BMI,body weight,model of end-stage liver disease score,blood loss,transfusions,operative time,cold ischemic time,length of hospital stay and ***:There was no donor *** cases needed to be converted to open *** median blood loss was 60 mL(range 20-800),median donor operative time was 6.77 h(range 2.93-11.53),median length of hospital stay was 4 days(range 2-22).Complication rate in donors classified following ClavienDindo was 6.4%(n=32)with one grade Ⅲ ***-year actual recipient overall survival was 91.4%;87.5% for adult recipients and 97.1% for pediatric ***-year actual graft overall survival was 90.6%;87.5% for adult recipients and 95.1% for pediatric ***-hospital mortality was 6%,9.1%(27/296)for adult recipients and 1.4%(3/205)for pediatric *** recipients’morbidity was 19.8%(n=99).Twenty-eight recipients(5.6%)had biliary and 22(4.4%)vascular ***(12.0%)recipients needed to

关键词： Living liver donor Innovation Robotic donor surgery Donor safety Minimally invasive donor surgery

Gene therapeutic approaches to inhibit hepatitis B virus replication

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World Journal of Hepatology 2015年第2期7卷 150-164页

作者： maren Gebbing Thorsten Bergmann Eric Schulz Anja Ehrhardt Institute of Virology and Microbiology Center for Biomedical Education and Research(ZBAF)Department of Human MedicineFaculty of HealthUniversity Witten/Herdecke58453 WittenGermany

Acute and chronic hepatitis B virus(HBV) infections remain to present a major global health problem. The infection can be associated with acute symptomatic or asymptomatic hepatitis which can cause chronic inflammation of the liver and over years this can lead to cirrhosis and the development of hepatocellularcarcinomas. Currently available therapeutics for chronically infected individuals aim at reducing viral replication and to slow down or stop the progression of the disease. Therefore, novel treatment options are needed to efficiently combat and eradicate this disease. Here we provide a state of the art overview of gene therapeutic approaches to inhibit HBV replication. We discuss non-viral and viral approaches which were explored to deliver therapeutic nucleic acids aiming at reducing HBV replication. Types of delivered therapeutic nucleic acids which were studied since many years include antisense oligodeoxynucleotides and antisense RNA, ribozymes and DNAzymes, RNA interference, and external guide sequences. More recently designer nucleases gained increased attention and were exploited to destroy the HBV genome. In addition we mention other strategies to reduce HBV replication based on delivery of DNA encoding dominant negative mutants and DNA vaccination. In combination with available cell culture and animal models for HBV infection, in vitro and in vivo studies can be performed to test efficacy of gene therapeutic approaches. Recent progress but also challenges will be specified and future perspectives will be discussed. This is an exciting time to explore such approaches because recent successes of gene therapeutic strategies in the clinic to treat genetic diseases raise hope to find alternative treatment options for patients chronically infected with HBV.

关键词： Gene therapy Hepatitis B virus Antisense nucleic acid RNA interference Designer nuclease Ribozyme DNAzyme Dominant negative mutant External guide sequence DNA vaccination

Coincidence of active Crohn's disease and florid endometriosis in the terminal ileum: A case report

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World Journal of Gastroenterology 2013年第27期19卷 4413-4417页

作者： Elke Kaemmerer maren Westerkamp Reinhard Kasperk Gerhard Niepmann Axel Scherer Nikolaus Gassler Department of Pediatrics and Institute of Pathology RWTH Aachen University Department of Surgery Luisenhospital Aachen Department of Radiology Luisenhospital Aachen Institute of Pathology RWTH Aachen University

Crohn's disease (CD), a variant of chronic inflammatory bowel disease, frequently affects the terminal ileum and coecal region. The clinical symptoms are often subtle and depend on the inflammatory activity of disease. In women of child-bearing age, florid intestinal endometriosis can simulate CD. Moreover, current pathophysiological concepts include intestinal endometriosis as a putative founder lesion for consecutive CD establishment. The report summarizes clinical and histomorphological data of a 35-year-old woman with the rare coincidence of florid intestinal endometriosis and CD both affecting the terminal ileum. The patient was suffering over 10 years from strong abdominal disorders including constipation, diarrhea, weight loss, and diffuse abdominal pain. In magnetic resonance imaging-Sellink, strong inflammation and intestinal obstruction of the terminal ileum were found. The laparoscopy revealed further evidence for existence of an inflammatory disease like CD, but brownish spots on the peritoneum were found indicative for endometriosis. Surgical resection of the terminal ileum and the coecal segment was performed followed by histopathological investigations. In transmural sections of the terminal ileum, histomorphological features of florid endometriosis intermingled with florid CD was found. The diagnostic findings were substantiated with a panel of immunohistological stainings. In conclusion, the findings demonstrate that florid endometriosis persists in florid CD lesions and the putative link between intestinal endometriosis and CD is more complex than previously assumed.

关键词： Crohn’s diseases Intestinal endometriosis Pathogenesis

Establishing minimum clinically important difference values for the Patient-Reported Outcomes Measurement Information System Physical Function, hip disability and osteoarthritis outcome score for joint reconstruction, and knee injury and osteoarthritis out

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World Journal of Orthopedics 2018年第3期9卷 41-49页

作者： Man Hung Jerry Bounsanga maren W Voss Charles L Saltzman Department of Orthopaedic Surgery Operations University of Utah Division of Public Health University of Utah Population Health Research Foundation University of Utah

AIM To establish minimum clinically important difference(MCID) for measurements in an orthopaedic patient population with joint *** Adult patients aged 18 years and older seeking care for joint conditions at an orthopaedic clinic took the Patient-Reported Outcomes Measurement Information System Physical Function(PROMIS~? PF) computerized adaptive test(CAT), hip disability and osteoarthritis outcome score for joint reconstruction(HOOS JR), and the knee injury and osteoarthritis outcome score for joint reconstruction(KOOS JR) from February 2014 to April 2017. MCIDs were calculated using anchorbased and distribution-based methods. Patient reports of meaningful change in function since their first clinic encounter were used as an *** There were 2226 patients who participated with a mean age of 61.16(SD = 12.84) years, 41.6% male, and 89.7% Caucasian. Mean change ranged from 7.29 to 8.41 for the PROMIS~? PF CAT, from 14.81 to 19.68 for the HOOS JR, and from 14.51 to 18.85 for the KOOS JR. ROC cut-offs ranged from 1.97-8.18 for the PF CAT, 6.33-43.36 for the HOOS JR, and 2.21-8.16 for the KOOS JR. Distribution-based methods estimated MCID values ranging from 2.45 to 21.55 for the PROMIS~? PF CAT; from 3.90 to 43.61 for the HOOS JR, and from 3.98 to 40.67 for the KOOS JR. The median MCID value in the range was similar to the mean change score for each measure and was 7.9 for the PF CAT, 18.0 for the HOOS JR, and 15.1 for the KOOS *** This is the first comprehensive study providing a wide range of MCIDs for the PROMIS? PF, HOOS JR, and KOOS JR in orthopaedic patients with joint ailments.

关键词： Hhip disability and osteoarthritis outcome score for joint reconstruction Patient-Reported Outcomes Measurement Information System Physical Function Knee injury and osteoarthritis outcome score for joint reconstruction Minimum clinically important difference Joint Physical function Minimum detectable change Arthroplasty Orthopaedics Clinical outcomes