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Chinese journal of Aeronautics 2023年第5期36卷 33-40页

作者： jörg schlüter Dan ZHAO Abhishek SARKAR School of Engineering Deakin UniversityWaurn Ponds 3216Australia College of Engineering University of CanterburyChristchurch 8041New Zealand School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore

A better understanding of the mixing behavior of excited turbulent mixing layers is critical to a number of aerospace applications.Previous studies of excited turbulent mixing layers focused on single frequency excitation or the excitation with fundamental and its second harmonic frequency.There is a lack of detailed studies on applying low and higher frequency excitation.In this study,we have performed large-eddy simulations of periodically excited turbulent mixing layers.The excitation consists of a fundamental frequency and its third harmonic.We have used phase-averaging to identify the vortex structure and strength in the mixing layer,and we have studied the vortex dynamics.Two different vortex paring mechanisms are observed depending on the phase shift between the two excitation frequencies.The influence of these two mechanisms on the mixing of a passive scalar is also studied.It is found that exciting the mixing layer with these low and high frequencies has initially an adverse influence on the mixing process;however,it improves the mixing further downstream of the splitter plate with the excitation using a phase shift ofΔφ=πshowing the best mixing performance.The present works shed lights on the fundamental vortex dynamics,and has great potential for aeronautical,automotive and combustion engineering applications.

关键词： Flow control Flow excitation Large eddy simulations Turbulent mixing layer Vortex dynamics

Laser-induced plasma formation in water with up to 400 mj double-pulse LIBS

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Plasma Science and Technology 2024年第1期26卷 93-100页

作者： Marion HENKEL Michelle SIEMENS Ralf METHLING Benjamin EMDE jörg HERMSDORF Steffen FRANKE Diego GONZALEZ Leibniz Institute for Plasma Science and Technology(INP) Felix-Hausdorff-Straße 2Greifswald 17489Germany Laser Zentrum Hannover e.V.(LZH) Hollerithallee 8Hannover 30419Germany

Double-pulse LIBS is a promising technique for deep-sea applications.LIBS measurements in shallow water with up to 400 mj each pulse were done to select laser parameters which promote optimized spectral line emission from plasma even at elevated pressures,where line broadening until loss of most of the spectral information can occur.Optical emission spectroscopy,using a Czerny-Turner spectrometer,has been applied to investigate the dependence of the emitted radiation on laser parameters and hydrostatic pressure.It has been found,that higher laser pulse energies,especially with short pulse delay as required in high water pressure,can also have an adverse effect on the measured spectrum.

关键词： double-pulse LIBS underwater plasma formation emission spectrosocpy

Challenging the term symbiosis in plant-microbe associations to create an understanding across sciences

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journal of Integrative Plant Biology 2024年第1期66卷 7-11页

作者： Anna Neubauer Daniela Aros‐Mualin Vicente Mariscal Péter Szövényi Department of Systematic and Evolutionary Botany University of ZurichZurich 8008Switzerland Zurich‐Basel Plant Science Center Zurich 8092Switzerland Instituto de Bioquímica Vegetal y Fotosíntesis CSIC y Universidad de SevillaSevilla 41092Spain

THE IMPORTANCE OF WELL DEFINED terMINOLOGY,Effective communication across fields and disciplines relies on well defined terminology.Standardized use of accurate definitions has been advocated by scientists across vari... 详细信息

关键词： terminology definition fields

In-situ study of the microstructure evolution during tension of a Mg-Y-Zn-Al alloy processed by rapidly solidified ribbon consolidation technique

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journal of Magnesium and Alloys 2024年第5期12卷 2024-2040页

作者： jen? Gubicza Kristián Máthis Péter Nagy Péter jenei Zoltán Heged?s Andrea Farkas jozef Vesely Shin-ichi Inoue Daria Drozdenko Yoshihito Kawamura Department of Materials Physics Faculty of Science E?tv?s Loránd University Department of Physics of Materials Faculty of Mathematics and Physics Charles University Deutsches Elektronen-Synchrotron DESY Magnesium Research Center Kumamoto University

Mg-Y-Zn-Al alloys processed by rapidly solidified ribbon consolidation（RSRC） technique exhibit an exceptional mechanical performance indicating promising application potential. This material has a bimodal microstructure consisting of fine recrystallized and coarse non-recrystallized grains with solute-rich stacking faults forming cluster arranged layers（CALs） and nanoplates（CANaPs）, or complete long period stacking ordered（LPSO） phase. In order to reveal the deformation mechanisms, in-situ synchrotron X-ray diffraction line profile analysis was employed for a detailed study of the dislocation arrangement created during tension in Mg-0.9% Zn-2.05% Y-0.15%Al（at%） alloy. For uncovering the effect of the initial microstructure on the mechanical performance, additional samples were obtained by annealing of the as-consolidated specimen at 300 and 400 ℃ for 2 h. The heat treatment at 300 ℃ had no significant effect on the initial microstructure, its evolution during tension and, thus, the overall deformation behavior under tensile loading. On the other hand,annealing at 400 ℃ resulted in a significant increase of the recrystallized grains fraction and a decrease of the dislocation density, leading to only minor degradation of the mechanical strength. The maximum dislocation density at the failure of the samples corresponding to the plastic strain of 10-25% was estimated to be about 16-20 × 1014m-2. The diffraction profile analysis indicated that most dislocations formed during tension were of non-basaland pyramidaltypes, what was also in agreement with the Schmid factor values revealed independently from orientation maps. It was also shown that the dislocation-induced Taylor hardening was much lower below the plastic strain of 3% than above this value, which was explained by a model of the interaction between prismatic dislocations and CANaPs/LPSO plates.

关键词： Mg-Zn-Y-Al alloy Long period stacking ordered (LPSO) phase Cluster arranged nanoplates (CANaPs) Annealing Tension Dislocation density Hardening

Graphene-calcium carbonate coating to improve the degradation resistance and mechanical integrity of a biodegradable implant

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journal of Magnesium and Alloys 2024年第1期12卷 394-404页

作者： Lokesh Choudhary Parama Chakraborty Banerjee R.K.Singh Raman Derrek E.Lobo Christopher D.Easton Mainak Majumder Frank Witte jörg F.Löffler Department of Mechanical and Aerospace Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Department of Chemical and Biological Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Nanoscale Science and Engineering Laboratory(NSEL) Bldg 37Monash UniversityClayton CampusMelbourneVIC 3800Australia CSIRO Materials Science and Engineering Bayview AvenueClaytonVIC 3168Australia julius Wolff Institute and Berlin Brandenburg Center for Regenerative Therapies Charité–Universitätsmedizin BerlinAugustenburger Platz 113353 BerlinGermany Laboratory of Metal Physics and Technology Department of MaterialsETH Zurich8093 ZurichSwitzerland

Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body environment.This necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical integrity.In this study,an AZ91 magnesium alloy,as a representative for a biodegradable Mg implant material,was modified with a thin reduced graphene oxide(rgO)-calcium carbonate(CaCO_(3))composite coating.Detailed analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity,and thus has the potential to greatly extend the related application field.

关键词： Graphene coating Biodegradable implant Hydroxyapatite Corrosion Magnesium alloy

Effects of neoadjuvant chemotherapy vs chemoradiotherapy in the treatment of esophageal adenocarcinoma:A systematic review and meta-analysis

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World journal of Gastroenterology 2024年第11期30卷 1621-1635页

作者： Armand Csontos Alíz Fazekas Lajos Szakó Nelli Farkas Csenge Papp Szilárd Ferenczi Szabolcs Bellyei Péter Hegyi András Papp Department of Surgery University of PécsMedical SchoolClinical CenterPécs H-7624BaranyaHungary Institute of Bioanalysis University of PécsMedical SchoolPécs H-7624BaranyaHungary Institute for Translational Medicine University of PécsMedical SchoolPécs H-7624BaranyaHungary Department of Emergency Medicine Clinical CenterUniversity of PécsMedical SchoolPécs 7624BaranyaHungary Department of Oncotherapy University of PécsMedical SchoolClinical CenterPécs H-7624BaranyaHungary Centre for Translational Medicine Semmelweis UniversityBudapest 1085Hungary Institute of Pancreatic Diseases Semmelweis UniversityBudapest H-1083Hungary

BACKGROUND Neoadjuvant therapy is an essential modality for reducing the clinical stage of esophageal cancer;however,the superiority of neoadjuvant chemotherapy(nCT)or neoadjuvant chemoradiotherapy(nCRT)is unclear.Therefore,a discussion of these two modalities is necessary.AIM To investigate the benefits and complications of neoadjuvant modalities.METHODS To address this concern,predefined criteria were established using the PICO protocol.Two independent authors performed comprehensive searches using predetermined keywords.Statistical analyses were performed to identify significant differences between groups.Potential publication bias was visualized using funnel plots.The quality of the data was evaluated using the Risk of Bias Tool 2(RoB2)and the GRADE approach.RESULTS Ten articles,including 1928 patients,were included for the analysis.Significant difference was detected in pathological complete response(pCR)[Pterms of survival,local or distal recurrence,or other clinical or surgical complications.The result of RoB2 was moderate,and that of the GRADE approach was low or very low in almost all cases.CONCLUSION Although nCRT may have a higher pCR rate,it does not translate to greater long-term survival.Moreover,nCRT is associated with higher 30-d mortality,although the specific cause for postoperative complications could not be identified.In the case of nCT,toxic side effects are suspected,which can reduce the quality of life.Given the quality of available studies,further randomized trials are required.

关键词： Neoadjuvant Chemotherapy Chemoradiotherapy Esophageal cancer Adenocarcinoma

Understanding Behavioral Manifestations of Obsessive-Compulsive Disorder in People with Intellectual Disabilities—A Qualitative Study

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Open journal of Psychiatry 2024年第2期14卷 67-90页

作者： Lena Grüter Matthias Grünke Department of Rehabilitation and Special Education University of Cologne Cologne Germany

Background: There is limited knowledge about obsessive-compulsive disorder (OCD) in people with intellectual disabilities (IDs). This paper describes the manifestation of compulsive behaviors associated with OCD at the behavioral level in people with ID in institutionalized settings. The aim was to gain nuanced insight into appropriate understanding and classification in this specific context, and derive implications for research and practice. Methods: Individual cases of people with ID (n = 7) were studied to assess compulsive symptoms through two days of on-site observation of the person with ID within the institution, guided group discussions (n = 28), and semi-structured interviews with key informants and caregivers of the person with ID (n = 20). Caregiver ratings of the compulsive behavior checklist were compiled. Data were analyzed using qualitative content analysis. Results: All forms of OCD were present. Characteristics of compulsive behaviors in people with ID at the behavioral level included less complex and more obvious compulsive acts, immediate responses, signs of tension, motor restlessness, facial expression changes, repetition, need for predictability, time-consuming behaviors, and aggressive reactions when these acts were interrupted. Some of the compulsive behaviors corresponded to the ICD-11 OCD code 6B20, and others to compulsions as a psychological symptom (MB23.4). Conclusions: OCD may manifest atypically at the behavioral level in people with ID, posing significant challenges for accurate classification due to symptom ambiguity. Follow-up differential diagnostic studies are needed to more accurately identify and differentiate OCD symptoms in people with ID. Further, disorder-specific guidelines for recognizing OCD in people with ID are needed for institutionalized settings without psychiatric-psychotherapeutic expertise.

关键词： People with Intellectual Disabilities Obsessive-Compulsive Disorder Compulsive Behavior Diagnostics Differential Diagnosis

Development of an active-site titrant for SARS-CoV-2 main protease as an indispensable tool for evaluating enzyme kinetics

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2349-2357页

作者： Rabea Voget julian Breidenbach Tobias Claff Alexandra Hingst Katharina Sylvester Christian Steinebach Lan Phuong Vu Renato H.Weiße Ulrike Bartz Norbert Sträter Christa E.Müller Michael Gütschow Pharmaceutical Institute Pharmaceutical&Medicinal ChemistryUniversity of BonnBonn 53121Germany Institute of Bioanalytical Chemistry Center for Biotechnology and BiomedicineLeipzig UniversityLeipzig 04103Germany Department of Natural Sciences University of Applied Sciences Bonn-Rhein-SiegRheinbach 53359Germany

A titrant for the SARS-CoV-2 main protease(M^(pro))was developed that enables,for the first time,the exact determination of the concentration of the enzymatically active M^(pro) by active-site titration.The covalent binding mode of the tetrapeptidic titrant was elucidated by the determination of the crystal structure of the enzyme–titrant complex.Four fluorogenic substrates of M^(pro),including a prototypical,internally quenched Dabcyl-EDANS peptide,were compared in terms of solubility under typical assay conditions.By exploiting the new titrant,key kinetic parameters for the M^(pro)-catalyzed cleavage of these substrates were determined.

关键词： COVID-19 SARS-CoV-2 Main protease Peptide nitriles Fluorogenic substrates Active-site titration X-ray crystallography Inner filter effect

Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： David j.Bottjer Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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Global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： Gregory j.Retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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