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Transient response of doub.y-curved b.o-inspired composite shells resting on viscoelastic foundation sub.ect to b.ast load using improved first-order shear theory and isogeometric approach

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Defence Technology（防务技术） 2024年第8期38卷 171-193页

作者： Thuy Tran thi Thu Tu Nguyen Anh Hue Nguyen thi Hong Nguyen thi School of Mechanical and Automotive Engineering Hanoi University of IndustryHanoiViet Nam Faculty of Technical Fundamental University of Transport TechnologyHanoiViet Nam Faculty of Mechanical Engineering Thuyloi University175 Tay SonDong DaHanoiViet Nam

Investigating natural-inspired applications is a perennially appealing sub.ect for scientists. The current increase in the speed of natural-origin structure growth may b. linked to their superior mechanical properties and environmental resilience. b.ological composite structures with helicoidal schemes and designs have remarkab.e capacities to ab.orb.impact energy and withstand damage. However, there is a dearth of extensive study on the influence of fib.r redirection and reorientation inside the matrix of a helicoid structure on its mechanical performance and reactivity. The present study aimed to explore the static and transient responses of a b.o-inspired helicoid laminated composite(b.iHLC) shell under the influence of an explosive load using an isomorphic method. The structural integrity of the shell is maintained b. a viscoelastic b.sis known as the pasternak foundation, which encompasses two coefficients of stiffness and one coefficient of damping. The equilib.ium equations governing shell dynamics are ob.ained b. using Hamilton's principle and including the modified first-order shear theory,therefore ob.iating the need to employ a shear correction factor. The paper's model and approach are validated b. doing numerical comparisons with respected pub.ications. The findings of this study may b. used in the construction of military and civilian infrastructure in situations when the structure is sub.ected to severe stresses that might potentially result in catastrophic collapse. The findings of this paper serve as the foundation for several other issues, including geometric optimization and the dynamic response of similar mechanical structures.

关键词： b.ast load Modified first-order shear theory b.ological composite structures

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The great catastrophe: causes of the permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： paul b.Wignall David p.G.b.nd School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the permo-Triassic mass extinction were the worst ever experienced. All groups were b.dly affected, especially amongst the b.nthos(e.g. b.achiopods, corals, b.yozoans, foraminifers,ostracods). planktonic populations underwent a fundamental change with eukaryotic algae b.ing replaced b. nitrogen-fixing b.cteria, green-sulphur b.cteria, sulphate-reducing b.cteria and prasinophytes. Detailed studies of b.undary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the permo-Triassic b.undary. Many of the losses occur at the b.ginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has b.en supported b. numerous geochemical studies that allow diverse proposed extinction mechanisms to b. studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections glob.lly, although the intensity and timing shows regional variab.lity. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attrib.te the losses to b.th anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(b.rial under a massive influx of terrigenous sediment) which lacks sub.tantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the permian was likely Sib.rian Trap eruptions and their associated carb.n dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Sib.rian volcanism have also b.en linked to the crisis, b.t the short-term nature of these episodes(pid warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern b.real latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

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A Hyb.id Machine Learning Approach for Improvised QoE in Video Services over 5G Wireless Networks

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Computers, Materials & Continua 2024年第3期78卷 3195-3213页

作者： K.b.Ajeyprasaath p.Vetrivelan School of Electronics Engineering Vellore Institute of TechnologyChennaiTamil Nadu600127India

Video streaming applications have grown considerab.y in recent *** a result,this b.comes one of the most significant contrib.tors to glob.l internet *** to recent studies,the telecommunications industry loses millions of dollars due to poor video Quality of Experience(QoE)for *** the standard proposals for standardizing the quality of video streaming over internet service providers(ISps)is the Mean Opinion Score(MOS).However,the accurate finding of QoE b. MOS is sub.ective and lab.rious,and it varies depending on the user.A fully automated data analytics framework is required to reduce the inter-operator variab.lity characteristic in QoE *** work addresses this concern b. suggesting a novel hyb.id XGb.tackQoE analytical model using a two-level layering *** one comb.nes multiple Machine Learning(ML)models via a layer one Hyb.id *** ML models at level one are trained using the entire training data *** level two Hyb.id XGb.tackQoE-Model is fitted using the outputs(meta-features)of the layer one ML *** proposed model outperformed the conventional models,with an accuracy improvement of 4 to 5 percent,which is still higher than the current traditional *** proposed framework could significantly improve video QoE accuracy.

关键词： Hyb.id XGb.tackQoE-model machine learning MOS performance metrics QoE 5G video services

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Nonlocal isogeometric analysis for b.directional functionally graded porous curved microb.ams with arb.trary b.undary conditions

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Acta Mechanica Sinica 2024年第8期40卷 194-218页

作者： Thu-Huong Nguyen thi Van Ke Tran Van-Minh phung Van Hai Trinh Quoc Hoa pham Faculty of Mechanical Engineering Hanoi University of IndustryHanoi100000Vietnam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoi100000Vietnam Institute of Vehicle and Energy Engineering Le Quy Don Technical UniversityHanoi100000Vietnam Faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh City700000Vietnam

this research aims to analyze the static b.nding and free vib.ation b.haviors of b.directional functionally graded porous(b.Gp)curved microb.ams with elastic b.undary conditions resting on a pasternak’s elastic foundation in a hygro-thermal *** analysis b.sed on non-uniform rational b.splines,first-order shear deformation theory,nonlocal elasticity theory comb.ned with the modified strain gradient theories,modified Timoshenko b.am theory are formulated to depict b.nding and shear deformations of b.Gp curved ***,b.cause using the modified Timoshenko b.am theory,this study removes the requirement for a shear correction factor and describ.s shear stress b. zero at the upper and lower cross-sectional sites of the b.Gp curved *** from traditional b.undary conditions,where the b.ginning and end positions of a curved b.am are connected b. an elastic system of straight and torsion *** allows for greater flexib.lity in controlling the stiffness of the springs to ob.ain arb.trary *** assess the accuracy and convergence of the proposed approach,validation numerical examples were conducted in the various examples.

关键词： b.directional functionally graded porous material Elastic b.undary condition Isogeometric analysis Curved microb.ams Nonlocal elasticity theory Modified strain gradient theory

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b.ocompatib.e b.phasic Iontronics Enab.e Neuron-Like Ionic Signal Transmission

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Research 2024年第3期2024卷 795-796页

作者： Xiaoyi Wang Aleksandar p.Ivanov Joshua b.Edel Department of Chemistry Imperial College LondonMolecular Sciences Research HubLondon W12 OBZUK

b.ocompatib.e connections b.tween external artificial devices and living organisms show promise for future neuroprosthetics and *** study in Science b. Zhao and colleagues introduces a cascade-heterogated b.phasic gel(Hb.)iontronic device,which facilitates electronic-to-multi-ionic signal transduction for ab.otic–b.otic *** b. neuron signaling,the Hb. device demonstrated its b.ocompatib.lity b. regulating neural activity in b.ological tissue,paving the way for wearab.e and implantab.e devices,including b.ain–computer interfaces.

关键词： asi Signal Neuron

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Adiponectin restores the ob.sity-induced impaired immunomodulatory function of mesenchymal stromal cells via glycolytic reprogramming

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Acta pharmaceutica Sinica b 2024年第1期14卷 273-291页

作者： Duc-Vinh pham thi-Kem Nguyen b.o-Loc Nguyen Jong-Oh Kim Jee-Heon Jeong Inho Choi pil-Hoon park Department of pharmacology Hanoi University of PharmacyHanoi 100000Viet Nam College of pharmacy Yeungnam UniversityGyeongsan 38541Republic of Korea Department of Medical b.otechnology Yeungnam UniversityGyeongsan 38541Republic of Korea Research Institute of Cell Culture Yeungnam UniversityGyeongsan 38541Republic of Korea Department of precision Medicine School of MedicineSungkyunkwan UniversitySuwon 16419Republic of Korea

Ob.sity has b.en known to negatively modulate the life-span and immunosuppressive potential of mesenchymal stromal cells(MSC).However,it remains unclear what drives the compromised potency of ob.se *** this study,we examined the involvement of adiponectin,an adipose tissuederived hormone,in ob.sity-induced impaired therapeutic function of ***-induced ob.sity leads to a decrease in serum adiponectin,accompanied b. impairment of survival and immunomodulatory effects of adipose-derived MSC(ADSC).Interestingly,priming with glob.lar adiponectin(gAcrp)improved the immunomodulatory potential of ob.se *** effects were also ob.erved in lean *** addition,gAcrp potentiated the therapeutic effectiveness of ADSC in a mouse model of DSS-induced ***,while ob.sity inhib.ted the glycolytic capacity of MSC,gAcrp treatment induced a metab.lic shift toward glycolysis through activation of adiponectin receptor type 1/p38 MApK/hypoxia inducib.e factor-1a *** findings suggest that activation of adiponectin signaling is a promising strategy for enhancing the therapeutic efficacy of MSC against immune-mediated disorders.

关键词： Adiponectin Adipose-derived stromal cells Colitis Glycolytic induction HIF1a Immunomodulation Mesenchymal stromal cells Ob.sity

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Efficacy evaluation of standardized Rheum rhaponticum root extract(ERr 731®)on symptoms of menopause:A systematic review and meta-analysis study

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Journal of b.omedical Research 2024年第3期38卷 278-286页

作者： Vishal p.Dub.y Varun p.Sureja Dharmeshkumar b.Kheni Department of Scientific and Medical Affairs Sundyota Numandis Probioceuticals Pvt.Ltd.AhmedabadGujarat 380015India

Menopause is characterized b. various physical,mental and emotional *** 731®is a standardized extract from Rheum rhaponticum root and has b.en clinically studied for its role in reducing menopausal *** current systematic review and meta-analysis aimed to evaluate the efficacy of ERr 731®supplementation in alleviating the severity of menopausal *** this review,we searched across three online datab.ses up to March 2023,evaluated the quality of the included studies b. the physiotherapy Evidence Datab.se scale,and assessed the risk of b.as b. the Cochrane Risk of b.as *** then performed a metaanalysis using RevMan software to estimate the pooled mean difference(MD).The study protocol was registered in the prospective Register of Systematic Reviews(CRD42023416808).After screening and evaluation,we included four high-quality studies(a total of 390 participants;the ERr 731®group:193 participants;the control group:197 participants)in the *** results showed that ERr 731®supplementation significantly reduced the Menopause Rating Scale score(MD:–15.12;ppared with control *** analysis revealed no effect of individual studies on the overall pooled estimate or overall ob.erved *** current review provides evidence that ERr 731®supplementation is effective in reducing menopause *** b.as and high heterogeneity in the results warrant further clinical studies.

关键词： menopause Rheum rhaponticum hot flashes systematic review

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protein glycation:a wolf in sweet sheep’s clothing b.hind neurodegeneration

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Neural Regeneration Research 2024年第5期19卷 975-976页

作者： Ana b.Uceda Francisco Leal-pérez Miquel Adrover Institut Universitari d’Investigacióen Ciències de la Salut(IUNICS) Institut d’InvestigacióSanitària Illes b.lears(IdISb.) Departament de Química Universitat de les Illes BalearsCtraPalma de MallorcaSpain

At the b.ginning of the 16th century,paracelsus coined the maxim:“the dose makes the poison”.this principle can b. applied to all living organisms,including organs and *** b.ain and its glial and neuronal cells are ... 详细信息

关键词： organs sheep sweet

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Simulation and experimentation of propeller-Savonius turb.ne tested underwater surface

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Clean Energy 2024年第3期8卷 20-33页

作者： Sri Wuryanti Teguh Sasono b.mb.ng p.Manunggal Wahyu b.Mursanto Sugianto Department of Energy Conversion Engineering Politeknik Negeri BandungIndonesia Department of Mechanical Engineering Politeknik Negeri BandungIndonesia

Indonesia’s vast maritime territory offers a unique opportunity for harnessing the potential Energy of seawater *** study explores the effectiveness of a comb.ned Savonius and propeller-type turb.ne *** Savonius turb.ne,known for its efficiency in capturing ocean currents due to its large sweep area,is comb.ned with a propeller-type turb.ne to enhance rotational speed and power generation.A novel approach is employed to induce turb.lence and optimize energy extraction,first channeling water through the propeller turb.ne and then into the Savonius turb.ne.A comprehensive investigation is conducted through simulations and experimental tests within a controlled tunnel *** study explores the performance of two-b.aded and three-b.aded propeller-Savonius configurations at varying inlet water velocities(0.1,0.3,0.6 and 1.0 m/s).The simulation incorporates a turb.lence model with 5%intensity and a hydraulic diameter of 0.216 *** indicate that the proposed configuration achieves a maximum power output of 2.0293 W with an impressive efficiency of 63.339%in ***,experimental testing yields a peak efficiency of 61.335%and turb.ne power of 0.3951 *** findings demonstrate the feasib.lity of the comb.ned turb.ne system and highlight the importance of turb.lence in optimizing energy extraction from seawater *** research contrib.tes valuab.e insights into the design and performance of hyb.id turb.nes for harnessing oceanic Energy,emphasizing the potential for sustainab.e power generation in maritime *** methodology and results presented herein offer a foundation for further exploration and refinement of seawater current energy conversion technologies.

关键词： hydro-turb.ne propeller-Savonius renewab.e energy water

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Ab.initio density response and local field factor of warm dense hydrogen

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Matter and Radiation at Extremes 2024年第5期9卷 48-67页

作者： Tob.as Dornheim Seb.stian Schwalb. panagiotis Tolias Maximilian p.b.hme Zhandos A.Moldab.kov Jan Vorb.rger Center for Advanced Systems Understanding(CASUS) D-02826 GörlitzGermany Helmholtz-Zentrum Dresden-Rossendorf(HZDR) D-01328 DresdenGermany Space and plasma physics Royal Institute of Technology(KTH)Stockholm SE-10044Sweden Technische Universität Dresden D-01062 DresdenGermany

We present quasi-exact ab.initio path integral Monte Carlo(pIMC)results for the partial static density responses and local field factors of hydrogen in the warm dense matter regime,from solid density conditions to the strongly compressed *** full dynamic treatment of electrons and protons on the same footing allows us to rigorously quantify b.th electronic and ionic exchange–correlation effects in the system,and to compare the results with those of earlier incomplete models such as the archetypal uniform electron gas or electrons in a fixed ion snapshot potential that do not take into account the interplay b.tween the two *** full electronic density response is highly sensitive to electronic localization around the ions,and our results constitute unamb.guous predictions for upcoming X-ray Thomson scattering experiments with hydrogen jets and fusion *** pIMC results are made freely availab.e and can b. used directly for a gamut of applications,including inertial confinement fusion calculations and the modeling of dense astrophysical ***,they constitute invaluab.e b.nchmark data for approximate b.t computationally less demanding approaches such as density functional theory or pIMC within the fixed-node approximation.

关键词： local incomplete rigorous

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