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The Journal of biomedical Research 2011年第4期25卷 280-286页

作者： Ashish Kumar Sharma Kunal Kishore Divya Sharma b.p srinivasan Shyam Sunder Agarwal Ashok Sharma Santosh Kumar Singh Samir Gaur Vijay Singh Jatav Department of pharmacology Gyan Vihar School of PharmacySuresh Gyan Vihar UniversityJagatpuraJaipur (Rajasthan)302025India Delhi Institute of pharmaceutical Sciences & Research Department of PharmacologyPushpviharSector Ⅲ.New Delhi 110017India

The present study investigated the antiarrhythmic activity of alcoholic extract of Tinospora cordifolia （T. cordifolia） in CaCl2 induced arrhythmia. CaCl2 （25 mg/kg） was administered by intravenous infusion （iv） to produce arrhythmia in rats. The animals were then treated with T. cordifolia extract （150, 250, and 450 mg/kg） and verapamil （5 mg/kg,iv）. Lead II electrocardiogram was monitored. plasma calcium, sodium and potassium levels were measured. In CaCl2 induced arrhythmia, heart rate was decreased by 41.10%, T. cordifolia at 150, 300, and 450 mg/kg decreased the heart rate by 26.30%, 29.16%, and 38.29%, respectively, and verapamil reduced the heart rate by 9.70% compared to the normal group. The pQRST waves were normalized and atrial and ventricular fibrillation was controlled in rats treated with verapamil and T. cordifolia. CaCl2 increased calcium and sodium levels and decreased potassium levels in blood. T. cordifolia dose-dependently decreased calcium and sodium levels and increased potassium levels. Hence, T. cordifolia can be used in antiarrhythmic clinical settings and beneficial in atrial and ventricular fibrillation and flutter and may be indicated in ventricular tachyarrhythmia.

关键词： Tinospora cordifolia arrhythmia cardioprotection.

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.bond 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 badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but 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 boreal latitudes

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

A Hybrid 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 considerably in recent *** a result,this becomes one of the most significant contributors to global 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 by MOS is subjective and laborious,and it varies depending on the user.A fully automated data analytics framework is required to reduce the inter-operator variability characteristic in QoE *** work addresses this concern by suggesting a novel hybrid XGbStackQoE analytical model using a two-level layering *** one combines multiple Machine Learning(ML)models via a layer one Hybrid *** ML models at level one are trained using the entire training data *** level two Hybrid XGbStackQoE-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： Hybrid XGbStackQoE-model machine learning MOS performance metrics QoE 5G video services

biocompatible b.phasic Iontronics Enable 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

biocompatible connections between external artificial devices and living organisms show promise for future neuroprosthetics and *** study in Science by Zhao and colleagues introduces a cascade-heterogated b.phasic gel(HbG)iontronic device,which facilitates electronic-to-multi-ionic signal transduction for abiotic–biotic *** by neuron signaling,the HbG device demonstrated its biocompatibility by regulating neural activity in biological tissue,paving the way for wearable and implantable devices,including brain–computer interfaces.

关键词： asi Signal Neuron

MXene-based Elastomer Mimetic StretchableSensors: Design, properties, and Applications

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Nano-Micro Letters 2024年第7期16卷 295-342页

作者： poushali Das parham Khoshbakht Marvi Sayan Ganguly Xiaowu(Shirley)Tang bo Wang Seshasai srinivasan Amin Reza Rajabzadeh Andreas Rosenkranz School of biomedical Engineering McMaster University1280 Main Street WestHamiltonON L8S 4L8Canada Department of Chemistry and Waterloo Institute for Nanotechnology(WIN) University of Waterloo200 University Ave WestWaterlooONCanada Centre for Eye and Vision Research(CEVR) 17W Hong Kong Science ParkShatinHong KongPeople’s Republic of China Chair of Functional Materials Department of Materials Science and EngineeringSaarland UniversitySaarbruckenGermany W booth School of Engineering practice and Technology McMaster University1280 Main Street WestHamiltonON L8S 4L7Canada Department for Chemical Engineering Biotechnology and MaterialsUniversity of ChileSantiagoChile

Flexible sensors based on MXene-polymer composites are highly prospective for next-generation wearable electronics used in human-machine *** of the motivating factors behind the progress of flexible sensors is the steady arrival of new conductive ***,a new family of 2D nanomaterials,have been draw-ing attention since the last decade due to their high electronic conduc-tivity,processability,mechanical robustness and chemical *** this review,we encompass the fabrication of MXene-based polymeric nanocomposites,their structure-property relationship,and applications in the flexible sensor ***,our discussion is not only lim-ited to sensor design,their mechanism,and various modes of sensing platform,but also their future perspective and market throughout the *** our article,we intend to fortify the bond between flexible matrices and MXenes thus promoting the swift advancement of flexible MXene-sensors for wearable technologies.

关键词： Flexible sensor 2D nanomaterials MXene Wearable and conductive Applications

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 biomedical Research 2024年第3期38卷 278-286页

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

Menopause is characterized by various physical,mental and emotional *** 731®is a standardized extract from Rheum rhaponticum root and has been 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 databases up to March 2023,evaluated the quality of the included studies by the physiotherapy Evidence Database scale,and assessed the risk of bias by the Cochrane Risk of bias *** 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 observed *** current review provides evidence that ERr 731®supplementation is effective in reducing menopause *** bias and high heterogeneity in the results warrant further clinical studies.

关键词： menopause Rheum rhaponticum hot flashes systematic review

protein glycation:a wolf in sweet sheep’s clothing behind 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 balears(IdISba) Departament de Química Universitat de les Illes BalearsCtraPalma de MallorcaSpain

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

关键词： organs sheep sweet

Simulation and experimentation of propeller-Savonius turbine 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 bambang 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 combined Savonius and propeller-type turbine *** Savonius turbine,known for its efficiency in capturing ocean currents due to its large sweep area,is combined with a propeller-type turbine to enhance rotational speed and power generation.A novel approach is employed to induce turbulence and optimize energy extraction,first channeling water through the propeller turbine and then into the Savonius turbine.A comprehensive investigation is conducted through simulations and experimental tests within a controlled tunnel *** study explores the performance of two-bladed and three-bladed propeller-Savonius configurations at varying inlet water velocities(0.1,0.3,0.6 and 1.0 m/s).The simulation incorporates a turbulence 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 turbine power of 0.3951 *** findings demonstrate the feasibility of the combined turbine system and highlight the importance of turbulence in optimizing energy extraction from seawater *** research contributes valuable insights into the design and performance of hybrid turbines for harnessing oceanic Energy,emphasizing the potential for sustainable 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-turbine propeller-Savonius renewable energy water

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： Tobias Dornheim Sebastian Schwalbe panagiotis Tolias Maximilian p.böhme Zhandos A.Moldabekov Jan Vorberger 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 both 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 between the two *** full electronic density response is highly sensitive to electronic localization around the ions,and our results constitute unambiguous predictions for upcoming X-ray Thomson scattering experiments with hydrogen jets and fusion *** pIMC results are made freely available and can be used directly for a gamut of applications,including inertial confinement fusion calculations and the modeling of dense astrophysical ***,they constitute invaluable benchmark data for approximate but computationally less demanding approaches such as density functional theory or pIMC within the fixed-node approximation.

关键词： local incomplete rigorous

performance and Safety Improvement of Induction Motors based on Testing and Evaluation Standards

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CES Transactions on Electrical Machines and Systems 2024年第3期8卷 310-318页

作者： Nkosinathi S.Khumalo Ntombizotwa p.Memane Udochukwu b.Akuru Department of Electrical Engineering Tshwane University of TechnologyPretoria 0183South Africa

The induction motor,which converts electrical energy into mechanical energy,has been recognized as the cornerstone of *** rotor of an induction motor can be either a squirrel cage rotor or a wound-type rotor,both existing as magnetless ***-phase squirrel cage induction motors are frequently utilized in industrial drives because they are dependable,have high starting torque,are selfstarting and ***-phase induction motors,on the other hand,are commonly used for small loads such as domestic appliances in form of modest fans,pumps and electric power *** South Africa,there have been reports of fires and explosions resulting in live and property loss because of induction motors that have not been thoroughly tested or are incorrectly labelled in terms of ratings,electrical safety and *** goal of this study is targeted at preventing end-user injuries and failures caused by non-compliant induction motors,by evaluating locally manufactured/imported induction motors based on tests and evaluation from standards(IEC and SANS).The study is conducted using experimental procedures at the Explosion prevention Technology and Rotating Machines(EpT and RM)laboratory,South African bureau of Standards(SAbS),South *** main finding from the study shows differences in the nameplate characteristics of various induction motors which could have detrimental effects such as production and operational downtime in their end-use industries,at later stages.

关键词： Compliance Induction motors International Electro-Technical standards(IEC) Nameplate Experimental tests South African National Standards(SANS)