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Numerical Simulation of Glottal Flow in Interaction with Self Oscillating Vocal Folds:Comparison of Finite Element Approximationwith a Simplified Model

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Communications in Computational Physics 2012年第8期12卷 789-806页

作者： P.Svácek j.Horácek Department of Technical Mathematics Faculty of Mechanical EngineeringCzech Technical University in PragueKarlovo nam.13Praha 212135Czech Republic Institute of Thermomechanics Academy of Sciences of the Czech RepublicDolejskova 5Praha 8Czech Republic

In this paper the numerical method for solution of an aeroelastic model describing the interactions of air flow with vocal folds is *** flow is modelled by the incompressible Navier-Stokes equations spatially discretizedwith the aid of the stabilized finite element *** motion of the computational domain is treated with the aid of the Arbitrary Lagrangian Eulerian *** structure dynamics is replaced by a mechanically equivalent system with the two degrees of freedom governed by a system of ordinary differential equations and discretized in time with the aid of an implicit multistep method and strongly coupled with the flow *** influence of inlet/outlet boundary conditions is studied and the numerical analysis is performed and compared to the related results from literature.

关键词： Finite element method arbitrary Lagrangian-Eulerian method biomechanics of voice production

Using classification assignment rules to assess land-use change impacts on forest biodiversity at local-to-national scales

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Forest Ecosystems 2018年第2期5卷 162-176页

作者： Kathrin Affeld Susan K. Wiser Ian j. Payton Miquel DeCaceres Manaaki Whenua - Landcare Research PO Box 69040 Lincoln 7640 New Zealand Lincoln University PO Box 85084 Lincoln 7647 New Zealand Forest Science Centre of Catalonia Ctra. Sant Llorenc km.2 E-25280 Solsona Spain

Background： Ecosystem representation is one key component in assessing the biodiversity impacts of land-use changes that will irrevocably alter natural ecosystems. We show how detailed vegetation plot data can be used to assess the potential impact of inundation by a proposed hydroelectricity dam in the Mokihinui gorge, New Zealand, on representation of natural forests. Specifically we ask： 1） How well are the types of forest represented Locally, regionally, and nationally; and 2） How does the number of distinct communities （i.e. beta diversity） in the target catchment compare with other catchments nationally？ Methods： For local and regional comparisons plant species composition was recorded on 45 objectively located 400 m2 vegetation plots established in each of three gorges, with one being the proposed inundation area of the Mokihinui lower gorge. The fuzzy classification framework of noise clustering was used to assign these plots to a specific alliance and association of a pre-existing national-scale classification. NationaLly, we examined the relationship between the number of alliances and associations in a catchment and either catchment size or the number of plots per catchment by fitting Generalised Additive Models. Results： The four alliances and five associations that were observed in the Mokihinui lower gorge arepresent in the region but limited locally. One association was narrowly distributed nationally, but is the mostfrequent association in the Mokihinui lower gorge; inundation may have consequences of national importance to its long-term persistence. That the Mokihinui lower gorge area had nearly twice as many plots that could not be assigned to pre- existing alliances and associations than either the Mokihinui upper or the Karamea lower gorges and proportionally more than the national dataset emphasises the compositional distinctiveness of this gorge. These outlier plots in the Mokihinui lower gorge may be unsorted assemblages of species or reflect

关键词： Beta-diversity Biodiversity conservation Environmental impacts Ecosystem representation Hydroelectricity dams Land-use change National vegetation classification Noise clustering New Zealand NVS databank Plant community composition

Wilsonian Renormalization Group and the Lippmann-Schwinger Equation with a Multitude of Cutoff Parameters

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Communications in Theoretical Physics 2018年第3期69卷 303-307页

作者： E.Epelbaum j.Gegelia Ulf-G.Meiβner Institut fur Theoretische Physik II Ruhr-Universitat Bochum D-44780 Bochum Germany Institute for Advanced Simulation Institut fur Kernphysik and Julich Center for Hadron Physics Forschungszentrum Jiilich D-52425 Julich Germany Tbilisi State University 0186 Tbilisi Georgia Helmholtz Institut fur Strahlen und Kernphysik and Bethe Center for Theoretical Physics Universitat Bonn D-53115 Bonn Germany

The Wilsonian renormalization group approach to the Lippmann-Schwinger equation with a multitude of cutoff parameters is introduced.A system of integro-differential equations for the cutoff-dependent potential is *** an illustration,a perturbative solution of these equations with two cutoff parameters for a simple case of an S-wave low-energy potential in the form of a Taylor series in momenta is *** relevance of the obtained results for the effective field theory approach to nucleon-nucleon scattering is discussed.

关键词： nucleon-nucleon scattering effective field theory renormalization group

Endogenous Glucocorticoids and Bone

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Bone Research 2013年第2期1卷 107-119页

作者： Hong Zhou Mark S. Cooper Markus j. Seibel Bone Research Program ANZAC Research Institute Concord Clinical School The University of Sydney Department of Endocrinology & Metabolism Concord Hospital

While the adverse effects of glucocorticoids on bone are well described, positive effects of glucocorticoids on the differentiation of osteoblasts are also observed. These paradoxical effects of glucocorticoids are dose dependent. At both physiologicaland supraphysiological levels of glucocorticoids, osteoblasts and osteocytes are the major glucocorticoid target cells. However, the response of the osteoblasts to each of these is quite distinct. At physiology levels, glucocorticoids direct mesenchymal progenitor cells to differentiate towards osteoblasts and thus increase bone formation in a positive way. In contrast with ageing, the excess production of glucocorticoids, at both systemic and intracellular levels, appear to impact on osteoblast and osteocytes in a negative way in a similar fashion to that seen with therapeutic glucocorticoids. This review will focus on therole of glucocorticoids in normal bone physiology, with particular emphasis on the mechanism by which endogenous glucocorticoids impact on bone and its constituent cells.

关键词： glucocorticoids mechanisms of action bone osteoblasts skeletal development Wnt signaling

Topological phases of a non-Hermitian coupled SSH ladder

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Chinese Physics B 2019年第10期28卷 269-273页

作者： j S Liu Y Z Han C S Liu Hebei Key Laboratory of Microstructural Material Physics School of Science Yanshan University

We study topological phases of a non-Hermitian coupled Su-Schrieffer-Heeger(SSH) ladder. The model originates from the brick-wall lattices in the two-row limit. The Hamiltonian can be brought into block off-diagonal form and the winding number can be defined with the determine of the block off-diagonal matrix. We find the determine of the offdiagonal matrix has nothing to do with the interleg hopping of the ladder. So the topological phases of the model are the same as those of the chains. Further numerical simulations verify the analysis.

关键词： topological phase non-Hermitian Su-Schrieffer-Heeger(SSH) ladder winding number

Late immune consequences of combat trauma: A review of trauma-related immune dysfunction and potential therapies

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Military Medical Research 2019年第4期6卷 340-353页

作者： Kelly B.Thompson Luke T.Krispinsky Ryan j.Stark Division of Critical Care Medicine Department of PediatricsVanderbilt University School of Medicine2200 Children’s WayNashvilleTN 37232USA Division of Pediatric Critical Care Medicine Department of PediatricsUniformed Services UniversityNaval Medical Center PortsmouthPortsmouthVA 23708USA

With improvements in personnel and vehicular body armor,robust casualty evacuation capabilities,and damage control resuscitation strategies,more combat casualties are surviving to reach higher levels of care throughout the casualty evacuation *** such,medical centers are becoming more accustomed to managing the deleterious late consequences of combat trauma related to the dysregulation of the immune *** this review,we aim to highlight these late consequences and identify areas for future research and therapeutic *** leads to the dysregulation of both the innate and adaptive immune responses,which places the injured at risk for several late consequences,including delayed wound healing,late onset sepsis and infection,multi-organ dysfunction syndrome,and acute respiratory distress syndrome,which are significant for their association with the increased morbidity and mortality of wounded *** mechanisms by which these consequences develop are complex but include an imbalance of the immune system leading to robust inflammatory responses,triggered by the presence of damage associated molecules and other immune-modifying agents following *** strategies to improve outcomes have been difficult to develop as the immunophenotype of injured personnel following trauma is variable,fluid and difficult to *** more information regarding the triggers that lead to immune dysfunction following trauma is elucidated,it may be possible to identify the immunophenotype of injured personnel and provide targeted treatments to reduce the late consequences of trauma,which are known to lead to significant morbidity and mortality.

关键词： Trauma Sepsis Compensatory anti-inflammatory response syndrome Persistent inflammationimmunosuppression and catabolism syndrome Immune dysfunction

Revealing and exploiting hierarchical material structure through complex atomic networks

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npj Computational Materials 2017年第1期3卷 163-170页

作者： Sebastian E.Ahnert William P.Grant Chris j.Pickard Theory of Condensed Matter Group Cavendish LaboratoryUniversity of CambridgeJJ Thomson AvenueCambridge CB30HEUK Sainsbury Laboratory University of CambridgeBateman StreetCambridge CB21LRUK Department of Materials Science&Metallurgy University of Cambridge27 Charles Babbage RoadCambridge CB30FSUK Advanced Institute for Materials Research Tohoku University 2-1-1 KatahiraAobaSendai 980-8577Japan

One of the great challenges of modern science is to faithfully model,and understand,matter at a wide range of *** with atoms,the vastness of the space of possible configurations poses a formidable challenge to any simulation of complex atomic and molecular *** introduce a computational method to reduce the complexity of atomic configuration space by systematically recognising hierarchical levels of atomic structure,and identifying the individual *** a list of atomic coordinates,a network is generated based on the distances between the *** the technique of modularity optimisation,the network is decomposed into *** procedure can be performed at different resolution levels,leading to a decomposition of the system at different scales,from which hierarchical structure can be *** considering the amount of information required to represent a given modular decomposition we can furthermore find the most succinct descriptions of a given atomic *** straightforward,automatic and general approach is applied to complex crystal *** show that modular decomposition of these structures considerably simplifies configuration space,which in turn can be used in discovery of novel crystal structures,and opens up a pathway towards accelerated molecular dynamics of complex atomic *** power of this approach is demonstrated by the identification of a possible allotrope of boron containing 56 atoms in the primitive unit cell,which we uncover using an accelerated structure search,based on a modular decomposition of a known dense phase of boron,γ-B_(28).

关键词： structure atomic complex

Cooperative hunting in a discrete predator-prey system

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International journal of Biomathematics 2020年第7期13卷 133-158页

作者： Yunshyong Chow Sophia R-j.jang Hua-Ming Wang Institute of Mathematics Academia Sinica Taipei 10617Taiwan Department of Mathematics and Statistics Texas Tech University LubbockTX 79409USA Department of Statistics Anhui Normal University Wuhu 241003AnhuiP.R.China

We propose and investigate a discrete-time predator-prey system with cooperative hunting in the predator *** model is constructed from the classical Nicholson-Bailey host-parasitoid system with density dependent growth rate.A sufficient condition based on the model parameters for which both populations can coexist is derived,namely that the predator’s maximal reproductive number exceeds *** study existence of interior steady states and their stability in certain parameter *** is shown that the system behaves asymptotically similar to the model with no cooperative hunting if the degree of cooperation is *** cooperative hunting,however,may promote persistence of the predator for which the predator would otherwise go extinct if there were no cooperation.

关键词： Cooperative hunting discrete predator-prey system predator persistence Neimark-Sacker bifurcation

Does (supra)gastric belching trigger recurrent hiccups?

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World journal of Gastroenterology 2010年第14期16卷 1795-1799页

作者： Wim P Hopman Mariёtte C van Kouwen André j Smout Department o Gastroenterology and Hepatology Radboud University Nijme gen Medical Centre 6500 HB Nijmegen The Netherlands Department of Gastroenterology and Hepa tology Academic Medical Center PO Box 22660 1100 DD Amsterdam The Netherlands

Twenty-four hours multichannel intraesophageal impedance and pH monitoring in a patient who suffered from recurrent hiccups for more than a year revealed frequent supragastric belching and pathological oesophageal acid exposure. Furthermore, a temporal relationship between the start of a hiccup episode and gastric belching was observed. The data support the hypothesis that there is an association between supragastric belching, persistent recurrent hiccups and gastro-oesophageal reflux disease, and that gastric belching may evoke hiccup attacks.

关键词： Hiccup Impedance and pH monitoring Gastro-oesophageal reflux Supragastric belching