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Up-regulation of oxidative stress and inflammation in the brain of albino wistar rats following sub-acute administration of Synclisia scabrida root extract

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TMR Integrative Medicine 2022年第30期6卷 1-7页

作者： Emmanuel Uchechukwu Modo ijeoma nina eke Utibe Evans Bassey Anthony Chibuzor Nnamudi Ekam Ime Akpakpan Okon Effiom Etim Iheanyichukwu Wopara Prosper Great Legborsi Department of Biochemistry Faculty of Basic Medical SciencesPAMO University of Medical SciencesPort HarcourtRivers StateNigeria Department of Biochemistry Faculty of SciencesUniversity of Port HarcourtPort HarcourtRivers StateNigeria

Objective: Synclisia scabrida is a medicinal plant used over the years for the treatment ofseveral medical conditions yet there is paucity of information on its systemic and organspecific toxicity. Consequently, sub-acute neurotoxicity of root extract of Synclisia scabridawas evaluated in albino Wistar rats. Methods: Thirty male albino rats with average weightof 140g were randomized into 5 groups consisting of 6 rats in each group. Group 1 was thecontrol while 50 mg/kg, 100 mg/kg, 200 mg/kg and 400 mg/kg of the root extract wereadministered to Groups 2, 3, 4 and 5 respectively for 28 days. Malondialdehyde,glutathione, nitric oxide, protein, tumour necrosis factor-α, acetylcholine, catalase andacetylcholinesterase levels were measured in brain homogenates. Body weight of theanimals and histology of the hippocampus and cerebral cortex were evaluated. Results:Root extract of Synclisia scabrida was observed to increase malondialdehyde concentrationand decrease antioxidants biomarkers when compared with the control. Significantly(p<0.05) increased TNF-α concentration and acetylcholinesterase activity caused by theextract when compared with the control was observed. The concentration of acetylcholinesignificantly decreased in Synclisia scabrida treated groups in comparison with the control.The histomorphology of the hippocampus and cerebral cortex revealed pyknotic pyramidalneurons in Synclisia scabrida treated rat relative to the control with normal pyramidalneurons. The body weight of the extract treated groups were significantly decreased whencompared to the control Group. Conclusion: The study has demonstrated that the rootextract of Synclisia scabrida induces and up-regulates oxidative stress and inflammation inthe brain of male albino Wistar rat coupled with reduced acetylcholine concentration hencethe extract possesses neurotoxic potentials.

关键词： Synclisia scabrida oxidative stress antioxidant inflammation neurotoxicity

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Silent battles:immune responses in asymptomatic SARS-CoV-2 infection

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Cellular & Molecular Immunology 2024年第2期21卷 159-170页

作者： nina Le Bert Taraz Samandari Program in Emerging Infectious Diseases Duke-NUS Medical SchoolSingaporeSingapore

SARS-CoV-2 infections manifest with a broad spectrum of presentations,ranging from asymptomatic infections to severe pneumonia and fatal outcomes.This review centers on asymptomatic infections,a widely reported phenomenon that has substantially contributed to the rapid spread of the pandemic.In such asymptomatic infections,we focus on the role of innate,humoral,and cellular immunity.Notably,asymptomatic infections are characterized by an early and robust innate immune response,particularly a swift type 1 IFN reaction,alongside a rapid and broad induction of SARS-CoV-2-specific T cells.Often,antibody levels tend to be lower or undetectable after asymptomatic infections,suggesting that the rapid control of viral replication by innate and cellular responses might impede the full triggering of humoral immunity.Even if antibody levels are present in the early convalescent phase,they wane rapidly below serological detection limits,particularly following asymptomatic infection.Consequently,prevalence studies reliant solely on serological assays likely underestimate the extent of community exposure to the virus.

关键词： COVID-19 asymptomatic cellular immunity antibody

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Exploring changes of precipitation extremes under climate change through global variable-resolution modeling

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Science Bulletin 2024年第2期69卷 237-247页

作者： Wei Sun Jian Li Rucong Yu nina Li Yi Zhang State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Tibetan Plateau Meteorology China Meteorological AdministrationChengdu 610072China Department of Atmospheric Science Yunnan UniversityKunming 650091China National Meteorological Center China Meteorological AdministrationBeijing 100081China 2035 Future Laboratory PIESAT Information Technology Co.Ltd.Beijing 100105China

Understanding the responses of precipitation extremes to global climate change remains limited owing to their poor representations in models and complicated interactions with multi-scale systems.Here we take the record-breaking precipitation over China in 2021 as an example,and study its changes under three different climate scenarios through a developed pseudo-global-warming(PGW)experimental framework with 60-3 km variable-resolution global ensemble modeling.Compared to the present climate,the precipitation extreme under a warmer(cooler)climate increased(decreased)in intensity,coverage,and total amount at a range of 24.3%-37.8%(18.7%-56.1%).With the help of the proposed PGW experimental framework,we further reveal the impacts of the multi-scale system interactions in climate change on the precipitation extreme.Under the warmer climate,large-scale water vapor transport converged from double typhoons and the subtropical high marched into central China,enhancing the convective energy and instability on the leading edge of the transport belt.As a result,the mesoscale convective system(Mcs)that directly contributed to the precipitation extreme became stronger than that in the present climate.On the contrary,the cooler climate displayed opposite changing characteristics relative to the warmer climate,ranging from the large-scale systems to local environments and to the Mcs.In summary,our study provides a promising approach to scientifically assess the response of precipitation extremes to climate change,making it feasible to perform ensemble simulations while investigating the multi-scale system interactions over the globe.

关键词： Precipitation extreme Climate change Pseudo-global-warming experiment Variable-resolution modeling Multi-scale system interaction

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Juvenile survival curves in a solitary ground squirrel with a prolonged hibernation:effects of individual characteristics,environment,and maternal investment

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Current Zoology 2024年第1期70卷 13-23页

作者： nina A.Vasilieva Liudmila E Savinetskaya Andrey V.Tchabovsky A.N.Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscow 119071Russia

Juvenile survival is a key life-history influence on population dynamics and adaptive evolution.We analyzed the effects of individual chara-cteristics,early environment,and maternal investment on juvenile survival in a large solitary hibernating rodent-yellow ground squirrel Spermophilus fulvus using Cox mixed-effects models.Only 48%of weaned pups survived to dispersal and 17%survived to hibernation.Early life expectancy was primarily determined by individual characteristics and,to a lesser extent,by the early environment.The strongest and pos-itive predictor of juvenile survival was body mass which crucially affected mortality immediately after weaning.Males suffered higher mortality than females after the onset of dispersal;however,the overall difference between sexes was partly masked by high rates of mortality in the first days after emergence in both sexes.Later emerged juveniles had lower life expectancy than the earliest pups.The overall effect of local juvenile density was positive.Prolonged lactation did not enhance juvenile survival:Pups nursed longer survived shorter than the young nursed for a shorter period.Our findings support the hypothesis that females of S.fulvus cannot effectively regulate maternal expenditures to mitigate the effects of unfavorable conditions on their offspring.The strategy to deal with seasonal time constraints on life history in female S.fulvus suggests an early termination of maternal care at the cost of juvenile quality and survival.This female reproductive strategy corresponds to a"fast-solitary"life of folivorous desert-dwelling S.fulvus and other solitary ground squirrels with prolonged hibernation.

关键词： early-life conditions ground squirrels hibernation juvenile mortality maternal investment survival curves

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A survey of energy-efficient strategies for federated learning in mobile edge computing

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Frontiers of Information Technology & Electronic Engineering 2024年第5期25卷 645-663页

作者： Kang YAN nina SHU Tao WU Chunsheng LIU Panlong YANG School of Electronic Engineering National University of Defense TechnologyHefei 230009China Department of Computing Hong Kong Polytechnic UniversityHong Kong 999077China School of Computer Science and Technology University of Science and Technology of ChinaHefei 230026China

With the booming development of fifth-generation network technology and Internet of Things,the number of end-user devices(EDs)and diverse applications is surging,resulting in massive data generated at the edge of networks.To process these data eficiently,the innovative mobile edge computing(MEC)framework has emerged to guarantee low latency and enable eficient computing close to the user traffic.Recently,federated learning(FL)has demonstrated its empirical success in edge computing due to its privacy-preserving advantages.Thus,it becomes a promising solution for analyzing and processing distributed data on EDs in various machine learning tasks,which are the major workloads in MEC.Unfortunately,EDs are typically powered by batteries with limited capacity,which brings challenges when performing energy-intensive FL tasks.To address these challenges,many strategies have been proposed to save energy in FL.Considering the absence of a survey that thoroughly summarizes and classifies these strategies,in this paper,we provide a comprehensive survey of recent advances in energy-efficient strategies for FL in MEC.Specifically,we first introduce the system model and energy consumption models in FL,in terms of computation and communication.Then we analyze the challenges regarding improving energy efficiency and summarize the energy-efficient strategies from three perspectives:learning-based,resource allocation,and client selection.We conduct a detailed analysis of these strategies,comparing their advantages and disadvantages.Additionally,we visually illustrate the impact of these strategies on the performance of FL by showcasing experimental results.Finally,several potential future research directions for energy-efficient FL are discussed.

关键词： Mobile edge computing Federated learning Energy-efficient

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Particle Swarm Optimization Bat Algorithm Path Automatically Planning Research for Police Drones in Hilly Cities

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Journal of Systems Science and Information 2024年第1期12卷 125-144页

作者： Jing XUE Zefu TAN nina DAI Guoping LEI Chao HE Chongqing Three Gorges University Chongqing 404020China

Mountain cities are complex asymmetric dynamic network architectures,and the flight of UAVs in this environment is subject to various constraints,while efficiency is a crucial factor in the trajectory planning of police UAVs,which need to maintain high efficiency and safe flight paths between their starting and ending points,but the traditional trajectory planning method cannot meet the requirements of rapid maneuvering of police UAVs.To achieve this,a 3D terrain map is built,an objective function is established for the flight cost in the UAV trajectory planning process,and a planning algorithm called particle swarm optimization bat algorithm(PSOBA)is proposed.PSOBA combines the characteristics of the bat algorithm(BA)and the particle swarm optimization algorithm(PSO)to improve population diversity and resolve the delayed convergence issue in the last phases of BA.Simulation results show that PSOBA is more effective than BA,with a search time for the best solution that is approximately 20.43%shorter and a convergence value of the objective function that is approximately 38%smaller.PSOBA is also able to plan a quicker,shorter,and safer flight path compared to other trail planning algorithms that enhance the bat algorithm.These findings suggest that PSOBA is a powerful algorithm with potential application value in UAV trajectory planning control in the mobile intelligence era.Contribute to the service of public social security.

关键词： hilly cities police drones asymmetrical trajectory planning particle swarm bat algorithm

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Bulking Up the Bay-Position Substituents Enables Enhanced Selectivity of Cs‑Symmetric Boron Subphthalocyanine−Subnaphthalocyanine Hybrids

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Precision Chemistry 2024年第4期2卷 161-181页

作者： nina F.Farac Alan J.Lough Timothy P.Bender Department of Chemical Engineering and Applied Chemistry University of TorontoTorontoOntario M5S 3E5Canada Department of Chemistry University of TorontoTorontoOntario M5S 3H6Canada Department of Materials Science and Engineering University of TorontoTorontoOntario M5S 3E4Canada Department of Mechanical and Industrial Engineering University of TorontoTorontoOntario M5S 3G8Canada

The precise synthesis of subporphyrinoid hybrids withπ-expanded topologies and unique material properties plays a promising role in the design of functional macrocycles.Easy,selective,and controllable routes to boron subphthalocyanine−subnaphthalocyanine hybrids,Bsub(Pc_(3‑p)-Ncp)s,are desirable for this purpose yet synthetically challenging due to random mixtures of Cs-,C3v-,and,in some cases,C1-symmetric compounds that form during traditional statistical mixed cyclotrimerizations.Herein,we addressed this issue by developing a sterically driven mixed cyclotrimerization with enhanced selectivity for the targeted Cs-symmetric hybrid and complete suppression of sterically crowded macrocyclic byproducts.This process,coupled with a rationally designed precursor bearing bulky phenyl substituents,enabled the synthesis and characterization of bay-position phenylated Ph2-(Rp)8Bsub(Pc_(2)-Nc_(1))hybrids with halogens(Rp=Cl or F)in their peripheral isoindole rings.Reaction selectivity ranged between 59 and 72%with remarkable yields,significantly higher than that of conventional mixed cyclotrimerizations.These findings were augmented by theoretical calculations on precursor Lewis basicity as guiding principles into hybrid macrocycle formation.Additionally,the incorporation of unfused phenyl groups and halogen atoms into the hybrid framework resulted in fine-tuned optical,structural,electronic,and electrochemical properties.This straightforward approach achieved improved selectivity and controlled narrowing of the product distribution,affording the efficient synthesis of structurally sophisticated Bsub(Pc_(2)-Nc_(1))hybrids.This then expands the library of 3-dimensionalπ-extended macrocycles for use in a range of applications,such as in optoelectronic devices with precisely tailored optical properties.

关键词： subphthalocyanine hybrids low-symmetry aromatic macrocycle selective cyclotrimerization sterically driven chemistry broad absorption material properties

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Hepatic rupture secondary to HELLP syndrome: outcomes in three cases

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World Journal of Emergency Medicine 2024年第1期15卷 56-58页

作者： Salvador Gomez-Carro Ruben R.Lozano-Salazar Kassandra Santos-Zaldívar Victor Andres Villasuso-Alcocer nina Méndez-Domínguez O'Horan General Hospital Merida 97000Mexico Highly Specialized Hospital of the Yucatan Peninsula Merida 97134Mexico National Institute of Perinatology.Mexico City 11000 Mexico

Hypertensive disorders of pregnancy,including chronic hypertension,gestational hypertension,and preeclampsia,are the most common complications in pregnant women,affecting approximately 15%of pregnancies.[1,2]Hemolysis,elevated liver enzymes,and low platelet count(HELLP syndrome)can occur in 0.2%-0.6%of all pregnancies,and 10%-15%of patients are diagnosed with preeclampsia.[3,4]Among its severe complications,liver hematoma is remarkable and may lead to liver rupture.Prompt identification of HELLP syndrome is crucial for proper therapeutic management and to avoid fatal outcomes[4,5]since when a hepatic hematoma occurs,the risk of rupture increases to 12%.[3,5]

关键词： rupture HELLP hypertension pregnancy

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More Fish to Fry

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China Weekly 2024年第2期 45-47页

作者： Wang nina 不详

NGO co-founder Zhang Tianhang talks about how chum salmon numbers in China are rebounding through cooperation with fishers,international practice and issuing‘fish passports’。

关键词： cooperation rebound fish

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Mechanochemical route to fabricate an efficient nitrate reduction electrocatalyst

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Nano Research 2024年第6期17卷 4889-4897页

作者： Yunliang Liu Zhiyu Zheng Sobia Jabeen Naiyun Liu Yixian Liu Yuanyuan Cheng Yaxi Li Jingwen Yu Xin Wu nina Yan Lei Xu Haitao Li Institute for Energy Research School of Energy and Power EngineeringJiangsu UniversityZhenjiang 212013China Jiangsu Engineering Technology Research Center of Biomass Composites and Addictive Manufacturing Institute of Agricultural Facilities and EquipmentJiangsu Academy of Agricultural SciencesNanjing 210014China Key Laboratory for Protected Agricultural Engineering in the Middle and Lower Reaches of Yangtze River Ministry of Agriculture and Rural AffairsNanjing 210014China

The electrochemical nitrate reduction reaction(NO_(3)RR)to ammonia under ambient conditions is a promising approach for addressing elevated nitrate levels in water bodies,but the progress of this reaction is impeded by the complex series of chemical reactions involving electron and proton transfer and competing hydrogen evolution reaction.Therefore,it becomes imperative to develop an electro-catalyst that exhibits exceptional efficiency and remarkable selectivity for ammonia synthesis while maintaining long-term stability.Herein the magnetic biochar(Fe-C)has been synthesized by a two-step mechanochemical route after a pyrolysis treatment(450,700,and 1000℃),which not only significantly decreases the particle size,but also exposes more oxygen-rich functional groups on the surface,promoting the adsorption of nitrate and water and accelerating electron transfer to convert it into ammonia.Results showed that the catalyst(Fe-C-700)has an impressive NH_(3)production rate of 3.5 mol·h^(−1)·gcat^(−1),high Faradaic efficiency of 88%,and current density of 0.37 A·cm^(−2)at 0.8 V vs.reversible hydrogen electrode(RHE).In-situ Fourier transform infrared spectroscopy(FTIR)is used to investigate the reaction intermediate and to monitor the reaction.The oxygen functionalities on the catalyst surface activate nitrate ions to form various intermediates(NO_(2),NO,NH_(2)OH,and NH_(2))and reduce the rate determining step energy barrier(*NO_(3)→*NO_(2)).This study presents a novel approach for the use of magnetic biochar as an electro-catalyst in NO_(3)RR and opens the road for solving environmental and energy challenges.

关键词： mechanochemical route magnetic biochar electron transfer nitrate ammonia

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