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Journal of Minerals and Materials Characterization and Engineering 2014年第4期2卷 351-361页

作者： ashok kr. mishra Vinod Kumar Rajesh kr. Srivastava BIT Sindri Dhanbad India BRCM College of Engineering & Technology Bahal India SKIET Kurukshetra India

In this investigation, optimization of tribological performance parameters of Al-6061T6 alloy reinforced with SiC (15% by weight) and Al2O3 (15% by weight) particulates having particle size of 37 μm each has been presented. The wear and frictional properties of the hybrid metal matrix composites have been studied by performing dry sliding wear test using pin-on-disc wear tester. A L27 orthogonal array is selected for the analysis of the data. From the test results it is observed that sliding distance has the significant contribution in controlling the friction and wear behaviour of hybrid composites. A confirmation test is also carried out to verify the accuracy of the results obtained through the optimization. In addition an optical micrograph test is also performed on the wear tracks to study the wear mechanism.

关键词： Metal Matrix Composites (MMCs) Friction Wear Taguchi Method Grey Relational Analysis Analysis of Variance (ANOVA)

14.1 W continuous-wave dual-end diode-pumped Er:Lu_(2)O_(3)laser at 2.85μm

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Chinese Optics Letters 2024年第1期22卷 84-89页

作者：梁洋洋李涛张百涛何京良 Sascha Kalusniak 赵显 Christian kr.nkel Key Laboratory of Laser&Infrared System Ministry of EducationShandong UniversityQingdao 266237China School of Information Science and Engineering Shandong Provincial Key Laboratory of Laser Technology and ApplicationShandong UniversityQingdao 266237China Institute of Novel Semiconductors State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Leibniz-Institut für kr.stallzüchtung(IKZ) Berlin 12489Germany

We present our efforts towards power scaling of Er:Lu_(2)O_(3)lasers at 2.85μ*** applying a dual-end diode-pumped resonator scheme,we achieve an output power of 14.1 W at an absorbed pump power of 59.7 W with a slope efficiency of 26%.In a single-end pumped resonator scheme,an output power of 10.1 W is reached under 41.9 W of absorbed pump *** the best of our knowledge,this is the first single crystalline mid-infrared rare-earth-based solid-state laser with an output power exceeding 10 W at room temperature.

关键词： high-power continuous-wave laser mid-infrared laser dual-end pump scheme

Geological and Morphological Features of the Karap?nar Sinkholes(Konya,Central Anatolia,Türkiye)

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Journal of Earth Science 2024年第5期35卷 1654-1668页

作者： Yasar Eren Seyda Parlar Berkant Coskuner Sükr. Arslan Department of Geological Engineering Faculty of Engineering and Natural SciencesKonya Technical UniversityKonya 42250Turkiye Prime Ministry Disaster and Emergency Management Authority Konya Provincial Directorate of Disaster and EmergencySelcuklu/Konya42100Turkiye

Karapınar region(Konya,Türkiye)is one of the important regions of the world in terms of sinkhole *** research aimed to map the sinkholes in detail,to determine their spatial distribution and geometrical *** this purpose,the long axes,short axes,depths and the proximity to settlements of the sinkholes were measured and their circumferences and areas were *** the studies,the relationship of the sinkholes with lithology,their cross sections,shapes and the related structures were determined and the sinkholes were divided into five main groups as following:Basement rock sinkholes,Obruk Plateau sinkholes,Seyithacı sinkholes,Siyeklik sinkholes and Basin *** d/l ratios of each sinkhole group were separately determined and ***,most of the d/l ratios are smaller than ***,the long axes are higher than the depth and it indicates that the shallow and wide sinkholes are common in the *** has been determined that the fracture systems in the region,as well as the lithology and groundwater factors,are quite effective in the formation and distribution of the sinkholes in the Karapınar *** the distance of the sinkholes to the settlements,Seyithac?sinkholes are the most risky group in the region because they are deep and close to the settlements.

关键词： Karapinar Sinkhole Turkiye Central Anatolia Obruk Plateau hydrogeology

Comparative analysis of microstructure,mechanical,and corrosion properties of biodegradable Mg-3Y alloy prepared by selective laser melting and spark plasma sintering

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Journal of Magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： P.Minárik M.Zemková S.Šašek J.Dittrich M.Knapek F.Lukáˇc D.Koutný J.Jaroš R.kr.l Faculty of Mathematics and Physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic Research Centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of Plasma Physics of the Czech Academy of Sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of Machine and Industrial Design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy Mg-3Y preparation by two modern powder metallurgy techniques–spark plasma sintering(SPS)and selective laser melting(SLM).The powder material was consolidated by both methods utilising optimised parameters,which led to very low porosity(∼0.3%)in the SLM material and unmeasurably low porosity in the SPS *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties,such as mechanical strength,deformability,and corrosion *** materials showed comparable strength of∼110 MPa in tension and compression and relatively good deformability of∼9%and∼21%for the SLM and SPS materials,*** corrosion resistance of the SPS material in 0.1 M NaCl solution was superior to the SLM one and comparable to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the SLM *** the other hand,one of the primary outcomes of this study is that the SPS consolidation method is very effective in the preparation of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation properties that might find practical applications.

关键词： Magnesium Yttrium Powder metallurgy Microstructure Mechanical strength Corrosion resistance

Inhibition of Ehrlich ascites carcinoma growth by melatonin:Studies with micro-CT

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Oncology Research 2024年第1期32卷 175-185页

作者： SEHER YILMAZ ZÜLEYHA DOĞANYIĞIT MERT OCAK EVRIM SUNA ARIKAN SÖYLEMEZ ASLI OKAN OFLAMAZ SÜMEYYE UÇAR ŞÜkr.ATEŞ AMMAD AHMAD FAROOQI Department of Anatomy Faculty of MedicineYozgat Bozok UniversityYozgatTurkey Department of Mechanical and Aerospace Engineering Case Western Reserve UniversityClevelandOhioUSA Department of Histology and Embriology Faculty of MedicineYozgat Bozok UniversityYozgatTurkey Department of Anatomy Faculty of DentistryAnkara UniversityAnkaraTurkey Department of Medical Biology Faculty of MedicineAfyonkarahisar Health Sciences UniversityAfyonTurkey Department of Anatomy Faculty of MedicineErciyes UniversityKayseriTurkey Department of Molecular Oncology Institute of Biomedical and Genetic Engineering(IBGE)IslamabadPakistan

Melatonin is a versatile indolamine synthesized and secreted by the pineal gland in response to the photoperiodic information received by the retinohypothalamic signaling *** has many benefits,such as organizing circadian rhythms and acting as a powerful *** aimed to show the antitumor effects of melatonin in both in vivo and in vitro models through the mammalian target of rapamycin(mTOR)signaling pathway and the Argyrophilic Nucleolar Regulatory Region(AgNOR),using the Microcomputed Tomography(Micro CT).Ehrlich ascites carcinoma(EAC)cells were administered into the mice by subcutaneous *** with solid tumors were injected intraperitoneally with 50 and 100 mg/kg melatonin for 14 *** measurements for the taken tumors were made with micro-CT imaging,immunohistochemistry(IHC),real-time polymerase chain reaction(PCR)and ***,the tumor tissue volume in the Tumor+100 mg/kg melatonin group was significantly lower than that in the other groups in the data obtained from micro-CT *** the IHC analysis,the groups treated with Tumor+100 mg/kg melatonin were compared when the mTOR signaling pathway and factor 8(F8)expression were compared with the control *** was determined that there was a significant decrease(p<0.05).Significant differences were found in the total AgNOR area/nuclear area(TAA/NA)ratio in the treatment groups(p<0.05).Furthermore,there were significant differences between the amount of mTOR mRNA for the phosphatidylinositol 3-kinase(PI3K),AKT Serine/Threonine Kinase(PKB/AKT)genes(p<0.05).Cell apoptosis was evaluated with Annexin V in an in vitro study with different doses of melatonin;It was observed that 100µg/mL melatonin dose caused an increase in the apoptotic cell *** this study,we have reported anti-tumor effects of melatonin in cell culture studies as well as in mice *** characterization of the melatonin-mediated cancer inhibitory effects will be valuable in advanc

关键词： Signaling pathway Apoptosis Real-time PCR AgNOR

Subpopulations of regulatory T cells are associated with subclinical atherosclerotic plaques,levels of LDL,and cardiorespiratory fitness in the elderly

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Journal of Sport and Health Science 2024年第3期13卷 288-296,I0002页

作者： Tim Böttrich Pascal Bauer Vincent Gröβer Magdalena Huber Hartmann Raifer Torsten Frech Svenja Nolte Theresa Dombrowski Franz Cemic Natascha Sommer Robert Ringseis Klaus Eder Karsten kr.ger Christopher Weyh Department of Exercise Physiology and Sports Therapy Institute of Sports ScienceJustus-Liebig-UniversityGiessen 35394Germany Department of Cardiology and Angiology Justus-Liebig-University GiessenGiessen 35392Germany Institute for Systems Immunology Center for Tumor und ImmunologyMarburg 35032Germany TH Mittelhessen Department of Computer ScienceUniversity of Applied Sciences GiessenGiessen 35390Germany Department of Internal Medicine Universities of Giessen and Marburg Lung Center(UGMLC)Member of the German Center for Lung Research(DZL)Giessen 35394Germany Excellence Cluster Cardio-Pulmonary Institute(CPI) Justus-Liebig UniversityGiessen 35394Germany Institute of Animal Nutrition and Nutrition Physiology Justus-Liebig-University GiessenGiessen 35390Germany

Background:Atherosclerosis forms the pathological basis for the development of cardiovascular *** pathological processes initially develop without clinically relevant symptoms,the identification of early markers in the subclinical stage plays an important role for initiating early *** is evidence that regulatory T cells(Tregs)are involved in the development of ***,the present study aimed to identify and investigate associations with Tregs and their subsets in a cohort of healthy elderly individuals with and without subclinical atherosclerotic plaques(SAP).In addition,various lifestyle and risk factors,such as cardiorespiratory fitness,were investigated as associated ***:A cross-sectional study was performed in 79 participants(male:n=50;age=63.6±3.7 years;body mass index=24.9±3.1 kg/m2;mean±SD)who had no previous diagnosis of chronic disease and were not taking *** of the carotids to identify SAP,cardiovascular function measurement for vascular assessment and a cardiorespiratory fitness test to determine peak oxygen uptake were ***,tests were conducted to assess blood lipids and determine glucose *** of Tregs and their subtypes(resting(rTregs)and effector/memory(mTregs))was performed by 8-chanel flow *** were categorized according to atherosclerotic plaque *** and logistic regression models were used to analyze associations between ***:SAP was detected in a total of 29 *** participants with plaque were older(64.8±3.6 years vs.62.9±3.5 years)and had higher peripheral systolic blood pressure(133.8±14.7 mmHg vs.125.8±10.9 mmHg).The participants with SAP were characterized by a lower percentage of rTregs(28.8%±10.7%vs.34.6%±10.7%)and a higher percentage of mTregs(40.3%±14.7%vs.30.0%±11.9%).Multiple logistic regression identified age(odds ratio(OR)=1.20(95%confidence interval(95%CI):1.011.42))and

关键词： Cardiorespiratory fitness Elderly Regulatory T cells Subclinical atherosclerosis

Sc元素添加对双辊铸轧Al−Cu−Li−Mg−Zr基合金热处理的影响

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Transactions of Nonferrous Metals Society of China 2024年第6期34卷 1759-1773页

作者： Rostislav kr.LÍK Barbora KŘIVSKÁ Lucia BAJTOŠOVÁ Mykhailo STOLBCHENKO Mirko SCHAPER Olexandr GRYDIN Miroslav CIESLAR Department of Physics of Materials Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116PragueCzech Republic Department of Materials Science Faculty of Mechanical EngineeringUniversity of PaderbornWarburger Straße 10033098PaderbornGermany

提出制备含Sc的Al−Cu−Li−Mg−Zr基合金带材的工艺方案。即先采用双辊铸轧技术制备近净形状的3 mm厚带材,再对其进行均匀化/固溶处理。研究两种Al−Cu−Li−Mg−Zr基双辊铸轧合金,其中一种添加质量分数为0.17%的Sc,另一种未添加Sc。两种合金... 详细信息

提出制备含Sc的Al−Cu−Li−Mg−Zr基合金带材的工艺方案。即先采用双辊铸轧技术制备近净形状的3 mm厚带材,再对其进行均匀化/固溶处理。研究两种Al−Cu−Li−Mg−Zr基双辊铸轧合金,其中一种添加质量分数为0.17%的Sc,另一种未添加Sc。两种合金均先在300℃下退火30 min,然后在450℃下退火30 min以及530℃下退火30 min,随后进行室温水淬。前两段退火后组织中生成了细小、弥散的Al_(3)Zr/Al_(3)(Sc,Zr)颗粒。最后的退火步骤起到了均匀化/固溶处理的作用。双辊铸轧材料的细小晶粒结构使含有主要合金元素的原始颗粒在较短的退火时间内溶解。缩短保温时间可以限制表面层中Li的耗尽和Al_(3)Zr/Al_(3)(Sc,Zr)弥散相的明显粗化。铸态含Sc材料已经具有明显细小的晶粒结构,而经均匀化/固溶处理后生成的Al_(3)(Sc,Zr)弥散相抑制了晶粒在高温下发生粗化。在后续180℃下时效处理后,形成了θʹ(Al_(2)Cu)、T1(Al_(2)CuLi)和S'(Al_(2)CuMg)强化相。在峰值时效状态下,屈服强度提高了200 MPa,这一数值与类似直接冷却铸造材料的相当,从而证实了所提方案的合理性。

关键词：显微组织力学性能 Al−Cu−Li基合金 Sc合金化双辊铸轧

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Rethinking neurodegenerative diseases:neurometabolic concept linking lipid oxidation to diseases in the central nervous system

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Neural Regeneration Research 2024年第7期19卷 1437-1445页

作者： Steinunn Sara Helgudóttir Anne Skøttrup Mørkholt Jacek Lichota Preben Bruun-Nyzell Mads Christian Andersen Nanna Marie Juhl kr.stensen Amanda kr.ger Johansen Mikela Reinholdt Zinn Hulda Maria Jensdóttir John Dirk Vestergaard Nieland 2N Pharma ApS NOVI Science ParkAalborgDenmark Molecular Pharmacology Group Department of Health Science and TechnologyAalborg UniversityAalborgDenmark

Currently,there is a lack of effective medicines capable of halting or reve rsing the progression of neurodegenerative disorde rs,including amyotrophic lateral sclerosis,Parkinson s disease,multiple sclerosis,or Alzheimer s *** the unmet medical need,it is necessary to reevaluate the existing para digms of how to to rget these *** considering neurodegenerative diseases from a systemic neurometabolic perspective,it becomes possible to explain the shared pathological *** innovative approach presented in this paper draws upon exte nsive research conducted by the authors and researchers *** this review,we highlight the importance of metabolic mitochondrial dysfunction in the context of neurodegenerative *** provide an overview of the risk factors associated with developing neurodegenerative disorders,including genetic,epigenetic,and environmental fa ***,we examine pathological mechanisms implicated in these diseases such as oxidative stress,accumulation of misfolded proteins,inflammation,demyelination,death of neurons,insulin resistance,dysbiosis,and neurotransmitter ***,we outline a proposal for the restoration of mitochondrial metabolism,a crucial aspect that may hold the key to facilitating curative therapeutic interventions for neurodegenerative disorders in forthcoming advancements.

关键词： brain disease carnitine palmitoyl transferase 1 epigenetics metabolism gut microbiome mitochondrial dysfunction neurodegeneration oxidative stress

Impact of Paenibacillus elgii supernatant on screening bacterial strains with potential for biotechnological applications

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Engineering Microbiology 2024年第3期4卷 1-15页

作者： I.C.Cunha-Ferreira C.S.Vizzotto T.D.Frederico J.Peixoto L.S Carvalho M.R.Tótola R.H.kr.ger Laboratory of Enzymology Department of Cellular BiologyUniversity of Brasília(UNB)Brasília70910-900Brazil Laboratory of Environmental Sanitation Department of Civil and Environmental EngineeringUniversity of Brasília(UNB)Brasília70910-900Brazil Laboratório de Biotecnologia e Biodiversidade para o Meio Ambiente Universidade Federal de Viçosa(UFV)Viçosa36570-900Brazil

The biotechnological industry faces a crucial demand for novel bioactive compounds,particularly antimicrobial agents,to address the rising challenge of bacterial resistance to current available *** strate-gies for cultivating naturally occurring microorganisms often limit the discovery of novel antimicrobial *** study presents a protocol for targeted selection of bacterial strains using the supernatant of Paenibacillus el-gii,which produces abundant signal molecules and antimicrobial *** samples were inoculated in these enriched culture media to selectively cultivate bacteria resistant to the supernatant,indicating their potential to produce similar *** bacterial strains isolated through this method were assessed for their antibac-terial *** addition,the functional annotation of the genome of one of these strains revealed several gene clusters of biotechnological *** study highlights the effectiveness of using this approach for selective cultivation of microorganisms with potential for biotechnological applications.

关键词： Prospecting Supernatant Antibacterial activity

Optimization of Biofuel Formulation by Mixture Design

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Advances in Chemical Engineering and Science 2024年第1期14卷 48-56页

作者： Konan Edmond Kouassi Abollé Abollé Kouamé Olivier-Marc Kouakou David Boa N’guessan Raymond kr. Kouassi Benjamin Yao Laboratory of Thermodynamics and Physical Chemistry of the Environment (LTPCM) UFR-SFA University of Nangui ABROGOUA Abidjan C&#244te d’Ivoire Laboratory of Fundamental and Applied Physics (LPFA) UFR-SFA University of Nangui ABROGOUA Abidjan C&#244te d’Ivoire Laboratory of Industrial Processes for the Synthesis of the Environment and New Energies (LAPISEN) of the Félix Houphouë t Boigny National Polytechnic Institute Yamoussoukro C&#244te d’Ivoire

With the full growth of energy needs in the world, several studies are now focused on finding renewable sources. The aim of this work is to optimise biofuel formulation from a mixture design by studying physical properties, such as specific gravity and kinematic viscosity of various formulated mixtures. Optimization from the mixture plan revealed that in the chosen experimental domain, the optimal conditions are: 40% for used frying oil (UFO), 50% for bioethanol and 10% for diesel. These experimental conditions lead to a biofuel with a density of 0.84 and a kinematic viscosity of 2.97 cSt. These parameters are compliant with the diesel quality certificate in tropical areas. These density and viscosity values were determined according to respective desirability values of 0.68 and 0.75.

关键词： Biofuel Optimization Mixture Design