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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

An integrative view of the signaling phenotype： Dynamic links between signals, physiology, behavior and social context

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Current Zoology 2014年第6期60卷 739-754页

作者： maren N. VITOUSEK David M. ZONANA Rebecca J. SAFRAN Department of Neurobiology and Behavior Comell University Ithaca New York 14853 USA Department of Ecology and Evolutionary Biology University of Colorado Boulder Colorado 80309 USA

Signal traits are often linked with the physiological state and behavior of their bearer. Direct examination of the causal links among these variables has provided substantial insight into the information content of signals, and into the costs and benefits of signal expression. Yet recent empirical work suggests that the social context in which signals are developed and displayed can play a major role not only in how signals are received, but also in coordinating and mediating the signaling phenotype itself. Here we review both well-established and emerging evidence for direct feedbacks among an individual＇s physiological state, be- havior, and signal elaboration. We then describe an integrative view of signaling that takes into account the bidirectional rela- tionships among components of phenotype and the social context in which signals are developed and displayed. Integrating dy- namic feedback between context and phenotype within models of the evolution and maintenance of signals may yield insights into how signals evolve, how signaling phenotypes are coordinated and maintained on ecological and evolutionary time scales, and how static signals continue to convey relevant phenotypic information about their bearer through time.

关键词： Behavior Phenotype Physiology Signal trait Social feedback Sexual selection

Ecological and evolutionary connections between morphology, physiology, and behavior

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Current Zoology 2014年第6期60卷 736-738页

作者： Rebecca J. SAFRAN maren N. VITOUSEK Guest Editors Department of Ecology and Evolutionary Biology University of Colorado Boulder Colorado 80309 USA Department of Neurobiology and Behavior Comell University Ithaca New York 14853 USA

1 Introduction Phenotype variation within populations both provides the raw material for and is the product of evolutionary change. An individual＇s phenotype, defined as the amalgamation of morphology, physiology, and behavior, is highly complex. It has been common to try to isolate each of these aspects of phenotype rather than directly examine their integration. For example, despite the demonstrated importance of single aspects of phenotype for acquiring mates it is well known that signal traits are not evaluated in isolation, but rather in conjunction with associated behaviors, and sometimes with other signal traits （Moiler and Pomiankowski, 1993; Candolin, 2003;

关键词：形态学生理学行为进化表型变异连接生态信号特性

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

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