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科研实践&实践科研南昌·西宁·拉萨·西安·低碳技术实践与研究

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科研实践&实践科研南昌·西宁·拉萨·西安·低碳技术实践与研究

Morbidity and Mortality of Acute Renal Failure in COVID-19 Patients in Intensive Care According to Waves/Variant: Case of the Grand Hôpital de l’Est Francilien Site de Meaux

“双碳”语境下绿色建筑出版研讨会

作者： D-ynamic Ultra low energy Innovation group

来源： cnki会议评论

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Open Journal of Internal Medicine 2024年第1期14卷 16-29页

作者： Khazy Anga Ariel Makembi Éric Amisi Éric Delpierre vivien Hong Tuan Ha Wilfrid Mbombo Jean Claude Mubenga Dan Kankonde Chris Nsituavibidila Lionel Diyamona Noelly Mukuna Gracia Likinda Tharcisse Mabiala Martin Mukenga Médard Bula-Bula Berthe Barhayiga Département d’Anesthésie Réanimation Université de Kinshasa Kinshasa République démocratique du Congo Service de Réanimation Grand H&ocircpital de l’Est Francilien Meaux France Département de Médecine Interne Université de Kinshasa Kinshasa République démocratique du Congo Service d’Anesthésie Réanimation Centre Hospitalier Monkole Kinshasa République démocratique du Congo Department of Anaesthesia and Intensive Care H&ocircpital Général de Référence de Kinshasa Kinshasa République démocratique du Congo Department of Anaesthesia and Intensive Care Université Protestante du Congo Kinshasa République démocratique du Congo

Introduction: The incidence of acute renal failure (ARF) varies between 20% and 40% of cases for COVID-19 patients admitted to the intensive care unit, with very high mortality, but heterogeneous according to the different epidemic waves, probably due to the genetic variant phenomenon of the virus. The aim of this study is to determine the morbidity and mortality of COVID-19 patients admitted with ARF to the intensive care unit of the Grand H?pital Est Francilien (GHEF) according to the waves and variants. Methods: Cross-sectional observational study of COVID-19 patients with ARF admitted to the intensive care unit of the GHEF site in Meaux covering the period from March 1st 2020 to December, 31st 2021. Per-hospitalisation and outcome data were collected and analysed with SPSS version 25.0 software using the Chi-square or Fischer’s exact test or Student’s t-test and logistic regression for p Results: A total of 86 patients were included. The mean age was higher (70 ± 8.5) in patients in the fourth wave than in the other waves (p = 0.015), with male predominance in all waves without significant difference. Co-morbidities: hypertension, diabetes, heart disease, dyslipidaemia and arrhythmia complete with fibrillation were present in all waves. The majority of patients were classified as KDIGO 1 for the different waves (1st: 61.9%, 2nd: 86.5%, 3rd: 80%, and 4th: 75%), with the same trend according to variant (alpha: 80%, beta: 75%, delta: 81.3%, omicron: 75%). Mortality by the wave was: 1st: 28.5%, 2nd: 37.5%, 3rd: 23% and 4th: 11%) and by variant: alpha: 24.2%, beta: 44.8%, delta: 20.7%, omicron: 10.3%). Overall mortality was 33.7%. Case fatality was higher in the fourth wave. Hypertension, shock, failure to recover renal function, acute lung oedema, ventilator-associated lung disease and hyperkalaemia were factors associated with mortality (p Conclusion: Acute renal failure is common in COVID-19 patients admitted to the intensive care unit, and m

关键词： Mortality COVID-19 Morbidity Renal Failure Intensive Care Unit

Field topologies in ideal and near-ideal magnetohydrodynamics and vortex dynamics

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Science China(Physics,Mechanics & Astronomy) 2015年第1期58卷 12-31页

作者： low B.C. High Altitude Observatory National Center for Atmospheric Research

Magnetic field topology frozen in ideal magnetohydrodynamics （MHD） and its breakage in near-ideal MHD are reviewed in two parts, clarifying and expanding basic concepts. The first part gives a physically complete description of the frozen field topology derived from magnetic flux conservation as the fundamental property, treating four conceptually related topics： Eulerian and La- grangian descriptions of three dimensional （3D） MHD, Chandrasekhar-Kendall and Euler-potential field representations, magnetic helicity, and inviscid vortex dynamics as a fluid system in physical contrast to ideal MHD. A corollary of these developments clar- ifies the challenge of achieving a high degree of the frozen-in condition in numerical MHD. The second part treats field-topology breakage centered around the Parker Magnetostatic Theorem on a general incompatibility of a continuous magnetic field with the dual demand of force-free equilibrium and an arbitrarily prescribed, 3D field topology. Preserving field topology as a global con- straint readily results in formation of tangential magnetic discontinuities, or, equivalently, electric current-sheets of zero thickness. A similar incompatibility is present in the steady force-thermal balance of a heated radiating fluid subject to an anisotropic thermal flux conducted strictly along its frozen-in magnetic field in the low-fl limit. In a weakly resistive fluid the thinning of current sheets by these general incompatibilities inevitably results field notwithstanding the small resistivity. Strong Faraday in sheet dissipation, resistive heating and topological changes in the induction drives but also macroscopically limits this mode of energy dissipation, trapping or storing free energy in self-organized ideal-MHD structures. This property of MHD turbulence captured by the Taylor hypothesis is reviewed in relation to the Sun＇s corona, calling for a basic quantitative description of the breakdown of flux conservation in the low-resistivity li

关键词： magnetic topology magnetic reconnection current sheets magnetic helicity thermal conduction solar corona magnetohy-drodynamics interstellar clouds

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Numerical simulation of hydrodynamic characteristics and bedload transport in cross sections of two gravel-bed rivers based on one-dimensional lateral distribution method

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International Journal of Sediment Research 2020年第2期35卷 203-216页

作者： Chien Pham Van vivien Chua Department of River Engineering and Disaster Management Faculty of Hydrology and Water ResourcesThuyloi University Unite de Mod'elisation Mathematiques et Informatiquedes Systemesco Complexes (UMMISCO) JEAI WARMIRDSorbonne Universit'e Department of Civil and Environmental Engineering Faculty of EngineeringNational University of Singapore

Accurate evaluation and prediction of bedload transport are crucial in studies of fluvial hydrodynamic characteristics and river *** paper presents a one-dimensional numerical model based on the one-dimensional lateral distribution method(1 D-LDM) and six classic bedload transport formulae that can be used to simulate hydrodynamic characteristics and bedload transport discharge in cross *** gravel-bed rivers,*** Danube River located approximately 70 km downstream from Bratislava in Slovakia and the Tolten River in south of Chile are used as *** the 1 D-LDM,gravity,bed shear stress,turbulent diffusion,and secondary flow are included to allow for accurate predictions of flow velocity and consequently bed shear stress in the cross *** classic formulae were applied to evaluate the non-dimensional bedload transport rate,and the bedload transport discharge through a river cross section is obtained by integrating the bedload transport rate over the width of the cross *** results show that the root mean square error(RMSE) and mean absolute error(MAE) of velocity and water discharge were less than 8% of the observed magnitude,while the correlation coefficient between model predictions and observations was close to *** formulae proposed by Ashida and Michiue(1972),in which particle collision with the bed is taken into account,and by Camenen and Larson(2005),which allows for yielding a non-zero bedload transport rate even when the bed shear stress is smaller than the critical bed shear stress value,appeared to be more appropriate for predicting the observed bedload transport rate in the studied cross sections of two gravel-bed *** non-uniform sediment mixtures were considered,the bedload transport discharge through a cross-section could change considerably by up to 22.5% of the observed *** relations proposed by Ashida and Michiue(1972) and Egiazaroff(1965) for parameterizing the hiding factor yielded more

关键词： Bedload Gravel-bed river One-dimensional lateral distribution method Bedload transport discharge

On-line Optimization of Biomimetic Undulatory Swimming by an Experiment-based Approach

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Journal of Bionic Engineering 2014年第2期11卷 213-225页

作者： Chunlin Zhou Kin Huat low Department of Control Science and Engineering Zhejiang University Hangzhou 310027 P. R. China School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore 639798 Singapore

An experiment-based approach is proposed to improve the performance of biomimetic undulatory locomotion through on-line optimization. The approach is implemented through two steps：（1） the generation of coordinated swimming gaits by artificial Central Pattern Generators （CPGs）; （2） an on-line searching of optimal parameter sets for the CPG model using Genetic Algorithm （GA）. The effectiveness of the approach is demonstrated in the optimization of swimming speed and energy effi- ciency for a biomimetic fin propulsor. To evaluate how well the input energy is converted into the kinetic energy of the pro- pulsor, an energy-efficiency index is presented and utilized as a feedback to regulate the on-line searching with a closed-loop swimming control. Experiments were conducted on propulsor prototypes with different fin segments and the optimal swimming patterns were found separately. Comparisons of results show that the optimal curvature of undulatory propulsor, which might have different shapes depending on the actual prototype design and control scheme. It is also found that the propulsor with six fin segments, is preferable because of hizher speed and lower energy efficiency.

关键词： robotic fish biomimetics locomotion optimization CPG GA

Scenario-based verification in presence of variability using a synchronous approach

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Frontiers of Computer Science 2013年第5期7卷 650-672页

作者： Jean-vivien MILLO Frederic MALLET Anthony COADOU S RAMESH INRIA Sophia-Antipolis Aoste team (INRIA/I3S/CNRS/UNS) Sophia-Antipolis 06560 France University of Nice Sophia Antipolis Sophia-Antipolis 06900 France Global General Motors R&D India Science Lab GM Technical Center India Bangalore 560066 India

This paper presents a new model of scenarios, dedicated to the specification and verification of system be- haviours in the context of software product lines （SPL）. We draw our inspiration from some techniques that are mostly used in the hardware community, and we show how they could be applied to the verification of software components. We point out the benefits of synchronous languages and mod- els to bridge the gap between both worlds.

关键词： Esterel UML MARTE scenario verification,feature interaction variability

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Challenges in membrane-based liquid phase separations

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Green Chemical Engineering 2021年第1期2卷 3-13页

作者： Ze-Xian low Huanting Wang Department of Chemical Engineering Monash UniversityClaytonVictoria3800Australia

Membranes are widely used in separation processes due to their low energy requirement,small footprint and *** membranes have been developed based on novel materials and fabrication techniques to address separation challenges in the field of membrane *** the case of liquid phase separations,ion-ion separation and chiral resolution using membranes have attracted growing interest for their applications such as in high-value mineral extraction and pharmaceutical ***,reverse osmosis operation favors ultra-high-pressure range for treating feed with higher salinity with higher water *** we highlight the latest development and design approaches of single species-selective membranes and pressure-resistant membranes and discuss the current limitations of membrane separation in the liquid *** subsequently review recent advancement in the fabrication techniques that enable the making of these membranes from emerging materials.

关键词： materials. separation phase.

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English Private Tutoring in Macao:Perceptions of Senior Secondary Three Students

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ECNU Review of Education 2019年第1期2卷 44-63页

作者： vivien Nga Man Chan The University of Hong Kong China

Purpose:This article examines how individual,school,and social factors shape the perceptions of students in Senior Secondary Three(SS3;in some schools called Form Six[F6])toward English private tutoring in ***/Approach/Methods:This is a comparative study of two F6 classes of an English-medium secondary school and four SS3 classes of a Chinese-medium secondary school in Macao,with a total number of 145 ***-methods approach(questionnaires and interviews)is employed in the ***:The respondents’participation in English tutoring is not very *** prefer to receive government-subsidized after-school tutoring taught by their schoolteachers more than feepaying English tutoring taught by tutors *** level of social competition and high tertiary enrollment rates contribute to this ***’needs and beliefs in English learning play key roles in determining their receipt of English ***/Value:Teachers may need better understanding of their students’needs so as to design suitable *** can consider more fully the types of tutoring that they provide for different kinds of *** government-subsidized after-school tutoring could be a plausible way to reduce educational inequality.

关键词： English Macao perceived needs private tutoring shadow education

Design and motion testing of a Multiple SMA fin driven BIUV

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Journal of Hydrodynamics 2019年第1期31卷 124-136页

作者： Yong-hua Zhang Jian-hui He Kinhuat low Department of Mechatronics Engineering Taizhou Vocational and Technical CollegeTaizhou 318000China School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore

Fishes interact with the fluid environment using various *** multiple control surfaces work in combination to produce the thrust and the balance torques in a steady swimming,to maneuver and to position themselves accurately even in turbulent *** motivate us to embark on a research program designed to develop an agile biologically inspired robotic fish based on the performance of multiple *** accomplish this goal,a mechanical ray-like fin actuated by the shape memory alloy (SMA) is developed,which can realize the oscillating motion,the undulating motion or even the complex three dimensional *** basic unit is the two opposite side SMA-driven plate,namely the fin *** a result,a lightweight bio-inspired fin is constructed by placing radially multiple SMA fin rays.A biologically inspired underwater vehicle (BIUV) is later built using the above multiple lightweight bio-inspired *** common arrangement styles of multiple fins on the BIUV are considered here:one is the posterior fin (for the oscillating motion) that is parallel to the anterior fins (for the undulating motion),another one is the posterior fin that perpendicular to the anterior *** kinematic modeling,the deformation modeling and the detecting of the SMA fin are *** thrust generation is also ***,an experiment is conducted to test the performance of the proposed two arrangement styles,including the comparison of the averaged propulsion velocity and the averaged thrust under certain kinematic ***,the influence of the frequency and the amplitude of the SMA fin ray on the propulsion performance is also investigated.

关键词： Oscillating undulating shape memory alloy (SMA) biologically inspired underwater vehicle (BIUV) fin ray