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The Impact of Network Topologies and Radio Duty Cycle Mechanisms on the RPL Routing Protocol Power Consumption
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作者 Amal Hkiri Hamzah Faraj +3 位作者 Omar Ben Bahri Mouna Karmani Sami Alqurashi Mohsen Machhout 《Computers, Materials & Continua》 SCIE EI 2024年第5期1835-1854,共20页
The Internet of Things(IoT)has witnessed a significant surge in adoption,particularly through the utilization of Wireless Sensor Networks(WSNs),which comprise small internet-connected devices.These deployments span va... The Internet of Things(IoT)has witnessed a significant surge in adoption,particularly through the utilization of Wireless Sensor Networks(WSNs),which comprise small internet-connected devices.These deployments span various environments and offer a multitude of benefits.However,the widespread use of battery-powered devices introduces challenges due to their limited hardware resources and communication capabilities.In response to this,the Internet Engineering Task Force(IETF)has developed the IPv6 Routing Protocol for Low-power and Lossy Networks(RPL)to address the unique requirements of such networks.Recognizing the critical role of RPL in maintaining high performance,this paper proposes a novel approach to optimizing power consumption.Specifically,it introduces a developed sensor motes topology integrated with a Radio Duty Cycling(RDC)mechanism aimed at minimizing power usage.Through rigorous analysis,the paper evaluates the power efficiency of this approach through several simulations conducted across different network topologies,including random,linear,tree,and elliptical topologies.Additionally,three distinct RDC mechanisms—CXMAC,ContikiMAC,and NullRDC—are investigated to assess their impact on power consumption.The findings of the study,based on a comprehensive and deep analysis of the simulated results,highlight the efficiency of ContikiMAC in power conservation.This research contributes valuable insights into enhancing the energy efficiency of RPL-based IoT networks,ultimately facilitating their widespread deployment and usability in diverse environments. 展开更多
关键词 WSN IoT radio duty cycles TOPOLOGIES
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Taurine attenuates activation of hepatic stellate cells by inhibiting autophagy and inducing ferroptosis
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作者 Sen Li Qian-Jun Ren +8 位作者 Can-Hao Xie Yang Cui Li-Tao Xu Yi-Dan Wang Su Li Xing-Qiu Liang Bin Wen Ming-Kun Liang Xiao-Fang Zhao 《World Journal of Gastroenterology》 SCIE CAS 2024年第15期2143-2154,共12页
BACKGROUND Liver fibrosis is a compensatory response during the tissue repair process in chronic liver injury,and finally leads to liver cirrhosis or even hepatocellular carcinoma.The pathogenesis of hepatic fibrosis ... BACKGROUND Liver fibrosis is a compensatory response during the tissue repair process in chronic liver injury,and finally leads to liver cirrhosis or even hepatocellular carcinoma.The pathogenesis of hepatic fibrosis is associated with the progressive accumulation of activated hepatic stellate cells(HSCs),which can transdiffer-entiate into myofibroblasts to produce an excess of the extracellular matrix(ECM).Myofibroblasts are the main source of the excessive ECM responsible for hepatic fibrosis.Therefore,activated hepatic stellate cells(aHSCs),the principal ECM producing cells in the injured liver,are a promising therapeutic target for the treatment of hepatic fibrosis.AIM To explore the effect of taurine on aHSC proliferation and the mechanisms involved.METHODS Human HSCs(LX-2)were randomly divided into five groups:Normal control group,platelet-derived growth factor-BB(PDGF-BB)(20 ng/mL)treated group,mmol/L,respectively)with PDGF-BB(20 ng/mL)treated group.Cell Counting Kit-8 method was performed to evaluate the effect of taurine on the viability of aHSCs.Enzyme-linked immunosorbent assay was used to estimate the effect of taurine on the levels of reactive oxygen species(ROS),malondialdehyde,glutathione,and iron concen-tration.Transmission electron microscopy was applied to observe the effect of taurine on the autophagosomes and ferroptosis features in aHSCs.Quantitative real-time polymerase chain reaction and Western blot analysis were performed to detect the effect of taurine on the expression ofα-SMA,Collagen I,Fibronectin 1,LC3B,ATG5,Beclin 1,PTGS2,SLC7A11,and p62.RESULTS Taurine promoted the death of aHSCs and reduced the deposition of the ECM.Treatment with taurine could alleviate autophagy in HSCs to inhibit their activation,by decreasing autophagosome formation,downregulating LC3B and Beclin 1 protein expression,and upregulating p62 protein expression.Meanwhile,treatment with taurine triggered ferroptosis and ferritinophagy to eliminate aHSCs characterized by iron overload,lipid ROS accumu-lation,glutathione depletion,and lipid peroxidation.Furthermore,bioinformatics analysis demonstrated that taurine had a direct targeting effect on nuclear receptor coactivator 4,exhibiting the best average binding affinity of-20.99 kcal/mol.CONCLUSION Taurine exerts therapeutic effects on liver fibrosis via mechanisms that involve inhibition of autophagy and trigger of ferroptosis and ferritinophagy in HSCs to eliminate aHSCs. 展开更多
关键词 Hepatic stellate cells AUTOPHAGY Ferroptosis Molecular docking TAURINE
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Global status and trends of metabolomics in diabetes: A literature visualization knowledge graph study
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作者 Hong Li Liu Li +6 位作者 Qiu-Qing Huang Si-Yao Yang Jun-Ju Zou Fan Xiao Qin Xiang Xiu Liu Rong Yu 《World Journal of Diabetes》 SCIE 2024年第5期1021-1044,共24页
BACKGROUND Diabetes is a metabolic disease characterized by hyperglycemia,which has increased the global medical burden and is also the main cause of death in most countries.AIM To understand the knowledge structure o... BACKGROUND Diabetes is a metabolic disease characterized by hyperglycemia,which has increased the global medical burden and is also the main cause of death in most countries.AIM To understand the knowledge structure of global development status,research focus,and future trend of the relationship between diabetes and metabolomics in the past 20 years.METHODS The articles about the relationship between diabetes and metabolomics in the Web of Science Core Collection were retrieved from 2002 to October 23,2023,and the relevant information was analyzed using CiteSpace6.2.2R(CiteSpace),VOSviewer6.1.18(VOSviewer),and Bibliometrix software under R language.RESULTS A total of 3123 publications were included from 2002 to 2022.In the past two decades,the number of publications and citations in this field has continued to increase.The United States,China,Germany,the United Kingdom,and other relevant funds,institutions,and authors have significantly contributed to this field.Scientific Reports and PLoS One are the journals with the most publications and the most citations.Through keyword co-occurrence and cluster analysis,the closely related keywords are"insulin resistance","risk","obesity","oxidative stress","metabolomics","metabolites"and"biomarkers".Keyword clustering included cardiovascular disease,gut microbiota,metabonomics,diabetic nephropathy,molecular docking,gestational diabetes mellitus,oxidative stress,and insulin resistance.Burst detection analysis of keyword depicted that"Gene","microbiota","validation","kidney disease","antioxidant activity","untargeted metabolomics","management",and"accumulation"are knowledge frontiers in recent years.CONCLUSION The relationship between metabolomics and diabetes is receiving extensive attention.Diabetic nephropathy,diabetic cardiovascular disease,and kidney disease are key diseases for future research in this field.Gut microbiota,molecular docking,and untargeted metabolomics are key research directions in the future.Antioxidant activity,gene,validation,mass spectrometry,management,and accumulation are at the forefront of knowledge frontiers in this field. 展开更多
关键词 DIABETES Metabolomics BIBLIOMETRIC CiteSpace VOSviewer
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Comprehensive prognostic and immune analysis of sterol Oacyltransferase 1 in patients with hepatocellular carcinoma
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作者 Chang-Jiao Gan Yue Zheng +1 位作者 Bin Yang Li-Min Cao 《World Journal of Hepatology》 2024年第3期439-451,共13页
BACKGROUND Sterol O-acyltransferase 1(SOAT1)is an important target in the diagnosis and treatment of liver cancer.However,the prognostic value of SOAT1 in patients with hepatocellular carcinoma(HCC)is still not clear.... BACKGROUND Sterol O-acyltransferase 1(SOAT1)is an important target in the diagnosis and treatment of liver cancer.However,the prognostic value of SOAT1 in patients with hepatocellular carcinoma(HCC)is still not clear.AIM To investigate the correlation of SOAT1 expression with HCC,using RNA-seq and gene expression data of The Cancer Genome Atlas(TCGA)-liver hepatocellular carcinoma(LIHC)and pan-cancer.METHODS The correlation between SOAT1 expression and HCC was analyzed.Cox hazard regression models were conducted to investigate the prognostic value of SOAT1 in HCC.Overall survival and disease-specific survival were explored based on TCGA-LIHC data.Biological processes and functional pathways mediated by SOAT1 were characterized by gene ontology(GO)analysis and the Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis of differentially expressed genes.In addition,the protein-protein interaction network and co-expression analyses of SOAT1 in HCC were performed to better understand the regulatory mechanisms of SOAT1 in this malignancy.RESULTS SOAT1 and SOAT2 were highly expressed in unpaired samples,while only SOAT1 was highly expressed in paired samples.The area under the receiver operating characteristic curve of SOAT1 expression in tumor samples from LIHC patients compared with para-carcinoma tissues was 0.748,while the area under the curve of SOAT1 expression in tumor samples from LIHC patients compared with GTEx was 0.676.Patients with higher SOAT1 expression had lower survival rates.Results from GO/KEGG and gene set enrichment analyses suggested that the PI3K/AKT signaling pathway,the IL-18 signaling pathway,the calcium signaling pathway,secreted factors,the Wnt signaling pathway,the Jak/STAT signaling pathway,the MAPK family signaling pathway,and cell–cell communication were involved in such association.SOAT1 expression was positively associated with the abundance of macrophages,Th2 cells,T helper cells,CD56bright natural killer cells,and Th1 cells,and negatively linked to the abundance of Th17 cells,dendritic cells,and cytotoxic cells.CONCLUSION Our findings demonstrate that SOAT1 may serve as a novel target for HCC treatment,which is helpful for the development of new strategies for immunotherapy and metabolic therapy. 展开更多
关键词 Sterol O-acyltransferase 1 Hepatocellular carcinoma PROGNOSTIC IMMUNE
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Rhizobium Inoculation and Micronutrient Addition Influence the Growth,Yield,Quality and Nutrient Uptake of Garden Peas(Pisum sativum L.)
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作者 MdAbdul Quddus MdAtaur Rahman +8 位作者 Razu Ahmed Mohammad Eyakub Ali Khokan Kumer Sarker MdAlamgir Siddiky Mohibur Rahman Lamya Ahmed Alkeridis Samy Sayed Ahmed Gaber Akbar Hossain 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第5期901-922,共22页
Garden pea productivity and qualities are hampered in zinc(Zn),boron(B),and molybdenum(Mo)deficient soil.Thus,the combination of micronutrients(i.e.,Zn,B,and Mo)and rhizobium is necessary to increase the productivity ... Garden pea productivity and qualities are hampered in zinc(Zn),boron(B),and molybdenum(Mo)deficient soil.Thus,the combination of micronutrients(i.e.,Zn,B,and Mo)and rhizobium is necessary to increase the productivity and quality of garden peas,since this management for garden peas is neglected in Bangladesh.Therefore,the present study was made to assess the effectiveness of rhizobium inoculant singly or in combination with the micronutrients(i.e.,Zn,B,and Mo)on growth,yield,nutrient uptake,and quality of garden peas.Treatments were:T_(1)=Control,T_(2)=Rhizobium inoculation at 50 g/kg seed,T_(3)=T_(2)+Zn_(3)Mo1,T_(4)=T_(2)+B_(2)Mo1,T_(5)=T_(2)+Zn_(3)B_(2),T_(6)=T_(2)+Zn_(3)B_(2)Mo1 and T_(7)=Zn_(3)B_(2)Mo1.All treatments were arranged in a randomized complete block design and repeated all treatments in three times.The application of 3 kg Zn,2 kg B,and 1 kg Mo ha^(−1)with inoculation of Rhizobium at 50 g kg^(−1)seed(T_(6))facilitated to increase of 44.8%in the green pod and 29.7%seed yield over control.The same treatment contributed to attaining the maximum nodulation(25.3 plant^(−1)),Vitamin C(43.5 mg 100 g^(−1)),protein content(22.2%),and nutrient uptake as well as accumulation in garden peas.Among all treatment combinations,treatment T_(6)was found superior to others based on microbial activities,soil fertility,and profitability.The results of the study found that the application of 3 kg Zn,2 kg B,and 1 kg Mo ha^(−1)in combination with Rhizobium inoculation(50 g kg^(−1)seed)can improve the yield and quality of garden peas.The results of the study have the potential for the areas,where there is no use of Rhizobium inoculant or Zn,B,and Mo fertilizer for cultivation of garden pea. 展开更多
关键词 NODULATION nutrient content Pisum sativum L. PROFITABILITY RHIZOBIUM Zn B Mo
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Clipping Effect on Growth and Plant Water Use Response to Diurnal Variation of Vapor Pressure Deficit in Cenchrus biflorus Roxb
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作者 Moussa Oumarou Abdoulaye Issoufou Hassane Bil-Assanou +1 位作者 Soulé Moussa Mainassara Zaman-Allah 《Journal of Agricultural Chemistry and Environment》 2024年第2期183-191,共9页
Cenchrus biflorus called Karangiya in the Hausa language is an annual pastoral grass which is a valuable herbaceous fodder in dry land region in the context of climate change. However, little is known about the plant ... Cenchrus biflorus called Karangiya in the Hausa language is an annual pastoral grass which is a valuable herbaceous fodder in dry land region in the context of climate change. However, little is known about the plant water use under the effects of cut in West Africa Sahel like Niger where the plant is a multipurpose grass species. Therefore, this study investigated the impact of grazing (simulated by shoot cuts) on biomass production. Cenchrus biflorus Roxb was grown on field plots and in pots and subjected to shoot cuts at different levels (3 cm and 5 cm from soil surface). The effect of shoot cuts on drought tolerance was evaluated by assessing the response of transpiration to the diurnal variation of vapor pressure deficit (VPD). Results showed that the biomass production varied in response to shoot cuts depending on the culture system, and the level or frequency of cuts. The mean biomass production increased significantly especially in field plots for 5 cm cuts compared to those at 3 cm and the control treatment. In addition, transpiration was highly increased in response to the VPD increase. Shoot cuts significantly reduced transpiration, whatever the level, largely because they reduced leaf surface. We concluded that moderate grazing (cuts to 5cm) can improve biomass production and allow better adaptation to water deficit as they significantly reduced water loss through transpiration. The study recommends the cropping of the Cenchrus biflorus as climate solution as it performs better under water deficit for improving grazing resilience in Niger. 展开更多
关键词 Cenchrus biflorus BIOMASS Vapor Pressure Deficit CUTTING GRAZING
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The growth of biopolymers and natural earthen sources as membrane/separator materials for microbial fuel cells:A comprehensive review
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作者 Gowthami Palanisamy Sadhasivam Thangarasu +5 位作者 Ranjith Kumar Dharman Chandrashekar S.Patil Thakur Prithvi Pal Singh Negi Mahaveer D.Kurkuri Ranjith Krishna Pai Tae Hwan Oh 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期402-431,I0010,共31页
Microbial fuel cell(MFC)technology has emerged as an effective solution for energy insecurity and bioremediation.However,identifying suitable components(particularly separators or membranes)with the required propertie... Microbial fuel cell(MFC)technology has emerged as an effective solution for energy insecurity and bioremediation.However,identifying suitable components(particularly separators or membranes)with the required properties,such as low cost and high performance,remains challenging and restricts practical application.Commercial membranes,such as Nafion,exhibit excellent performance in MFC.However,these membranes have high production costs,which considerably increase the overall MFC unit cell cost.Among the numerous types,the separators or membranes developed from biopolymers and naturally occurring earthen sources have proven to be a novel and efficient concept due to their natural abundance,cost-effectiveness(approximately$20 m^(-2),$5 m^(-2),and$1 kg-1for biopolymers,ceramics,and earthensources,respectively),structural properties,proton transportation,manufacturing and modification ease,and environmental friendliness.In this review,we emphasize cost-effective renewable green materials(biopolymers,bio-derived materials,and naturally occurring soil,clay,ceramics or minerals)for MFC applications for the first time.Biopolymers with good thermal,mechanical,and water retention properties,sustainability,and environmental friendliness,such as cellulose and chitosan,are typically preferred.Furthermore,the modification or introduction of various functional groups in biopolymers to enhance their functional properties and scale MFC power density is explored.Subsequently,separator/membrane development using various bio-sources(such as coconut shells,banana peels,chicken feathers,and tea waste ash)is described.Additionally,naturally occurring sources such as clay,montmorillonite,and soils(including red,black,rice-husk,and Kalporgan soil)for MFC were reviewed.In conclusion,the existing gap in MFC technology was filled by providing recommendations for future aspects based on the barriers in cost,environment,and characteristics. 展开更多
关键词 BIOMEMBRANE Bioseparator Microbial fuel cell Energy harvesting BIOENERGY Wastewater treatment
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Development of Pandemic Monitoring System Based on Constellation of Nanosatellites
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作者 Omar Ben Bahri Abdullah Alhumaidi Alotaibi 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期1249-1263,共15页
Covid-19 is a global crisis and the greatest challenge we have faced.It affects people in different ways.Most infected people develop a mild to moderate form of the disease and recover without hospitalization.This pre... Covid-19 is a global crisis and the greatest challenge we have faced.It affects people in different ways.Most infected people develop a mild to moderate form of the disease and recover without hospitalization.This presents a problem in spreading the pandemic with unintentionally manner.Thus,this paper provides a new technique for COVID-19 monitoring remotely and in wide range.The system is based on satellite technology that provides a pivotal solution for wireless monitoring.This mission requires a data collection technique which can be based on drones’technology.Therefore,the main objective of our proposal is to develop a mission architecture around satellite technology in order to collect information in wide range,mostly,in areas suffer network coverage.A communication method was developed around a constellation of nanosatellites to cover Saudi Arabia region which is the area of interest in this paper.The new proposed architecture provided an efficient monitoring application discussing the gaps related to thermal imaging data.It reached 15.8 min as mean duration of visibility for the desired area.In total,the system can reach a coverage of 5.8 h/day,allowing to send about 21870 thermal images. 展开更多
关键词 ANTENNA data transmission design NETWORK SIMULATION wireless communication
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Study on Technology Clusters for Direct Utilization of CO2-Rich Natural Gas and Construction of Hybrid System for Energy and Chemicals Production 被引量:2
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作者 Wu Qing 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第2期1-9,共9页
Based on industrial production with an annual capacity of million tons of methanol,ammonia/urea,etc.,a platform technology is developed for direct,green,efficient,and high-value mega-size utilization of the CO2-rich n... Based on industrial production with an annual capacity of million tons of methanol,ammonia/urea,etc.,a platform technology is developed for direct,green,efficient,and high-value mega-size utilization of the CO2-rich nature gas,which is the technology of CO2-rich natural gas dry reforming and hydrogen reaction.The following technologies are discussed,such as CO2-rich natural gas dry reforming integrated with the Fischer-Tropsch synthesis to olefins(FTO)technology for producing high value-added linear alpha olefins(LAO);CO2-rich natural gas dry reforming integrated with low carbon olefin linear hydroformylation technology to produce higher carbon alcohols;direct methanol production from CO2 and hydrogen;and the new cutting edge technology of photo-catalytic process.In addition,simple techno-economic evaluations of two technologies mentioned above are discussed.The CO2-rich natural gas dry reforming integrated with FTO technology can achieve about 30%of internal rate return(IRR),while the low carbon olefin linear hydroformylation technology could have a static payback period of 2.57 years when the capacity of 2-propylhexanol(2-PH)reaches 100 kt/a.Based on the mega-size green and high-efficient CO2-rich natural gas direct utilization technology,a hybrid energy and chemical production system framework with good prospects is preliminarily designed.A modern industry zone with an annual capacity of more than 10 Mt of CO2 converted to high value-added products is underway. 展开更多
关键词 CO2-riched natural gas dry reforming Fischer-Tropsch to olefins Fischer-Tropsch to aromatics linear hydroformylation techno-economic evaluation
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Anatomical and Molecular Identification of Ornamental Plant Ficus L.Species
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作者 Abtisam Binnoubah Rim Hamdy +8 位作者 Osama G.Ragab Ahmed M.El-Taher Ahmed Abou El-Yazied Fatmah A.Safhi Hala A.Elzilal Ashwaq T.Althobaiti Salha M.ALshamrani Diaa Abd El Moneim Ahmed El-Banhawy 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第5期1329-1347,共19页
This present study includes twelve species that represent the Ficus genus,namely;aspera,carica,tinctoria subsp.gibbosa,hirta,hispida,neriifolia,palmata,pumila,racemosa,septica,sur,and sycomorus,belonging to the Morace... This present study includes twelve species that represent the Ficus genus,namely;aspera,carica,tinctoria subsp.gibbosa,hirta,hispida,neriifolia,palmata,pumila,racemosa,septica,sur,and sycomorus,belonging to the Moraceae family.The species samples were collected from various locations in Egypt.The study focused on the anatomical and molecular characteristics of mature foliage leaves.Since the identification and classification of taxa are highly dependent on the anatomical features of leaves,the anatomical characteristics were recorded in the form of a comparison between the examined plants in the data matrix.This study aims to contribute to the identification of the studied species based on the anatomical details of the matured leaves.Anatomical characterization includes the variations in upper and lower epidermal layers that are covered by a thin or thick cuticle;the number of palisade and spongy layers;crystals;secretory elements;lithocysts;the midrib zone has parenchyma associated with mechanical tissue,vascular system,and investigation of trichomes;on the other hand,in the current study,the phylogenetic analysis was conducted by using the ITS and 5.8 S sequences.From the analysis of all the available data,it could be stated that there is an overall agreement with the anatomical character dendrogram. 展开更多
关键词 ITS TRICHOMES leaf anatomy FICUS MORACEAE
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Abundance and Source Identification of Polycyclic Aromatic Hydrocarbons in Sediments of the Ivory Coastal Zone (Toukouzou Hozalem-Assinie)
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作者 Laure Emma Oura Vanh Eric-Simon Zran +5 位作者 Georges Kouadio Horo Koné Affoué Tindo Sylvie Konan Albert Trokourey Kouassi Benjamin Yao Fofana Bakary 《American Journal of Analytical Chemistry》 CAS 2023年第1期12-27,共16页
Polycyclic aromatic hydrocarbons (PAHs) are strongly associated with agricultural, residential, transportation, industrial and petroleum activities. In this study, the presence of PAHs (polycyclic aromatic hydrocarbon... Polycyclic aromatic hydrocarbons (PAHs) are strongly associated with agricultural, residential, transportation, industrial and petroleum activities. In this study, the presence of PAHs (polycyclic aromatic hydrocarbons) was investigated in sediments of the ivory coastal zone (Toukouzou Hozalem-Assinie). The main objectives of this study were to determine the abundance and to predict the source of PAHs in the sediments. Gas chromatography-mass spectrometry (GC-MS) was used to analyze sixteen priority PAHs. Total PAHs concentrations were from 1.31 to 3992.68 mg/kg in sediment with an average concentration of (307.54 ± 16.10) mg/kg. Among all PAHs, Naphthalene (Nap = 332.72 mg/kg) and Phenanthrene (Phe = 41.75 mg/kg) were found in the highest concentration, whereas Benzo (k) Fluoranthene was found in the least concentration in the range of 0 - 0.85 mg/kg (mean 0.24 mg/kg). Bassam-Modeste Lagune (BML) sampling site was the site with the highest concentration of total PAHs (all 16 PAHs) compared to the others due to their location in a highly populated estuary area that receives commercial, tourism, port, petroleum and heavy industrial activities. Diagnostic ratios were used to determine the sources of PAHs and suggested that the PAH profile in the sediments was dominated by 2 and 3 ring PAHs. The patterns of PAH compounds in sediment indicated that contamination is from mixed sources, with a strong indication of petrogenic contamination potentially from spills of fuel, oil and industrial activities. 展开更多
关键词 Polycyclic Aromatic Hydrocarbons SEDIMENT Source ABUNDANCE Ivorian Coastal
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Old-growth mixed dipterocarp forests show variable losses and gains in aboveground biomass and standing carbon over forty years
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作者 Sisira Ediriweera Champika Bandara +8 位作者 Tithira Lakkana Shanika Jayasinghe David Woodbury Arun Dayanandan B.M.P.Singhakumara Xiangcheng Mi I.A.U.N.Gunatilleke C.V.S.Gunatilleke Mark SAshton 《Forest Ecosystems》 SCIE CSCD 2024年第1期14-23,共10页
Background:No studies have documented long-term trends in aboveground biomass(AGB)for mixed-dipterocarp forests(MDF),the dominant rain forest type in tropical wet equatorial Asia.In our study,we sought to document suc... Background:No studies have documented long-term trends in aboveground biomass(AGB)for mixed-dipterocarp forests(MDF),the dominant rain forest type in tropical wet equatorial Asia.In our study,we sought to document such trends over forty years across three sites representing lowland to lower montane elevations.Methods:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth forest.We measured trees for diameter at breast height that we identified to species and tagged.We took wood samples to calculate species wood-specific gravity.We re-measured plots in 1998 and again in 2018.Results:We show standing AGB for all sites combined to be 517.52 Mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 Mg·ha^(-1).No differences exist among sites in AGB primarily because of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the same.Relatively few species represented a high proportion of the AGB with the top five species comprising between 34%and 65%,depending upon site and year sampled.One species,Mesua nagassarium,represented a disproportionately large amount of AGB and decline over time,particularly at the low elevation site.Conclusions:Our results are directly relevant to estimating AGB and standing carbon sequestered in MDF.Our study is the first to demonstrate varying but overall,declining trends in amounts of AGB among forests making predictions of biomass and standing carbon in MDF difficult over wide regions. 展开更多
关键词 Western ghats Shorea spp. Southeast Asia Sri Lanka Tropical rain forest Wood specific gravity
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RPL-Based IoT Networks under Decreased Rank Attack:Performance Analysis in Static and Mobile Environments
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作者 Amal Hkiri Mouna Karmani +3 位作者 Omar Ben Bahri Ahmed Mohammed Murayr Fawaz Hassan Alasmari Mohsen Machhout 《Computers, Materials & Continua》 SCIE EI 2024年第1期227-247,共21页
The RPL(IPv6 Routing Protocol for Low-Power and Lossy Networks)protocol is essential for efficient communi-cation within the Internet of Things(IoT)ecosystem.Despite its significance,RPL’s susceptibility to attacks r... The RPL(IPv6 Routing Protocol for Low-Power and Lossy Networks)protocol is essential for efficient communi-cation within the Internet of Things(IoT)ecosystem.Despite its significance,RPL’s susceptibility to attacks remains a concern.This paper presents a comprehensive simulation-based analysis of the RPL protocol’s vulnerability to the decreased rank attack in both static andmobilenetwork environments.We employ the Random Direction Mobility Model(RDM)for mobile scenarios within the Cooja simulator.Our systematic evaluation focuses on critical performance metrics,including Packet Delivery Ratio(PDR),Average End to End Delay(AE2ED),throughput,Expected Transmission Count(ETX),and Average Power Consumption(APC).Our findings illuminate the disruptive impact of this attack on the routing hierarchy,resulting in decreased PDR and throughput,increased AE2ED,ETX,and APC.These results underscore the urgent need for robust security measures to protect RPL-based IoT networks.Furthermore,our study emphasizes the exacerbated impact of the attack in mobile scenarios,highlighting the evolving security requirements of IoT networks. 展开更多
关键词 RPL decreased rank attacks MOBILITY random direction model
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Leech Poecilobdella manillensis protein extract ameliorated hyperuricemia by restoring gut microbiota dysregulation and affecting serum metabolites
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作者 Xia Liu Xing-Qiu Liang +6 位作者 Tian-Cai Lu Zhe Feng Min Zhang Nan-Qing Liao Feng-Lian Zhang Bo Wang Li-Sheng Wang 《World Journal of Gastroenterology》 SCIE CAS 2024年第29期3488-3510,共23页
BACKGROUND Hyperuricemia(HUA)is a public health concern that needs to be solved urgently.The lyophilized powder of Poecilobdella manillensis has been shown to significantly alleviate HUA;however,its underlying metabol... BACKGROUND Hyperuricemia(HUA)is a public health concern that needs to be solved urgently.The lyophilized powder of Poecilobdella manillensis has been shown to significantly alleviate HUA;however,its underlying metabolic regulation remains unclear.AIM To explore the underlying mechanisms of Poecilobdella manillensis in HUA based on modulation of the gut microbiota and host metabolism.METHODS A mouse model of rapid HUA was established using a high-purine diet and potassium oxonate injections.The mice received oral drugs or saline.Additionally,16S rRNA sequencing and ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry-based untargeted metabolomics were performed to identify changes in the microbiome and host metabolome,respectively.The levels of uric acid transporters and epithelial tight junction proteins in the renal and intestinal tissues were analyzed using an enzyme-linked immunosorbent assay.RESULTS The protein extract of Poecilobdella manillensis lyophilized powder(49 mg/kg)showed an enhanced anti-trioxypurine ability than that of allopurinol(5 mg/kg)(P<0.05).A total of nine bacterial genera were identified to be closely related to the anti-trioxypurine activity of Poecilobdella manillensis powder,which included the genera of Prevotella,Delftia,Dialister,Akkermansia,Lactococcus,Escherichia_Shigella,Enterococcus,and Bacteroides.Furthermore,22 metabolites in the serum were found to be closely related to the anti-trioxypurine activity of Poecilobdella manillensis powder,which correlated to the Kyoto Encyclopedia of Genes and Genomes pathways of cysteine and methionine metabolism,sphingolipid metabolism,galactose metabolism,and phenylalanine,tyrosine,and tryptophan biosynthesis.Correlation analysis found that changes in the gut microbiota were significantly related to these metabolites.CONCLUSION The proteins in Poecilobdella manillensis powder were effective for HUA.Mechanistically,they are associated with improvements in gut microbiota dysbiosis and the regulation of sphingolipid and galactose metabolism. 展开更多
关键词 Gut microbiota Metabolism Multi-omics Poecilobdella manillensis Sphingolipid metabolism pathway Galactose metabolism pathway HYPERURICEMIA
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Homogeneity-Breaking Instability of Periodic Solutions of Gierer-Meindardt Model
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作者 Aying Wan Zhiqiang Song +1 位作者 Hongyan Lin Nan Xiang 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第2期62-67,共6页
The homogeneity-breaking instability of the periodic solutions triggered by Hopf bifurcations of a diffusive Gierer-Meinhart system is studied in this paper.Sufficient conditions on the diffusion coefficients and the ... The homogeneity-breaking instability of the periodic solutions triggered by Hopf bifurcations of a diffusive Gierer-Meinhart system is studied in this paper.Sufficient conditions on the diffusion coefficients and the cross diffusion coefficients were derived to guarantee the occurrence of the aforementioned homogeneity-breaking instability. 展开更多
关键词 Gierer-Meindardt model CROSS-DIFFUSION homogeneity-breaking instability Hopf bifurcations
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This work was supported by the European Research Council Advanced Grant(ETAP-742985 to H.T.and J.F.)and by the Ministry of Science and Technology(grant 110-2636-B-005-001 to K.-J.L.).
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作者 Yu Zhang Yuan Fu +29 位作者 Wenfei Xian Xiuli Li Yong Feng Fengjiao Bu Yan Shi Shiyu Chen Robin van Velzen Kai Battenberg Alison M.Berry Marco G.Salgado Hui Liu Tingshuang Yi Pascale Fournier Nicole Alloisio Petar Pujic Hasna Boubakri M.Eric Schranz Pierre-Marc Delaux Gane Ka-Shu Wong Valerie Hocher Sergio Svistoonoff Hassen Gherbi Ertao Wang Wouter Kohlen Luis G.Wall Martin Parniske Katharina Pawlowski Philippe Normand Jeffrey J.Doyle Shifeng Cheng 《Plant Communications》 SCIE CSCD 2024年第1期130-147,共18页
Plant root-nodule symbiosis(RNS)with mutualistic nitrogen-fixing bacteria is restricted to a single clade of angiosperms,the Nitrogen-Fixing Nodulation Clade(NFNC),and is best understood in the legume family.Nodulatin... Plant root-nodule symbiosis(RNS)with mutualistic nitrogen-fixing bacteria is restricted to a single clade of angiosperms,the Nitrogen-Fixing Nodulation Clade(NFNC),and is best understood in the legume family.Nodulating species share many commonalities,explained either by divergence from a common ancestor over 100 million years ago or by convergence following independent origins over that same time period.Regardless,comparative analyses of diverse nodulation syndromes can provide insights into constraints on nodulation—what must be acquired or cannot be lost for a functional symbiosis—and the latitude for Plant Communications Genomic landscape of nodulation variation in the symbiosis.However,much remains to be learned about nodulation,especially outside of legumes.Here,we employed a large-scale phylogenomic analysis across 88 species,complemented by 151 RNA-seq libraries,to elucidate the evolution of RNS.Our phylogenomic analyses further emphasize the uniqueness of the transcription factor NIN as a master regulator of nodulation and identify key muta-tions that affect its function across the NFNC.Comparative transcriptomic assessment revealed nodule-specific upregulated genes across diverse nodulating plants,while also identifying nodule-specific and nitrogen-response genes.Approximately 70%of symbiosis-related genes are highly conserved in the four representative species,whereas defense-related and host-range restriction genes tend to be lineage specific.Our study also identified over 900000 conserved non-coding elements(CNEs),over 300000 of which are unique to sampled NFNC species.NFNC-specific CNEs are enriched with the active H3K9ac mark and are correlated with accessible chromatin regions,thus representing a pool of candidate regula-tory elements for genes involved in RNS.Collectively,our results provide novel insights into the evolution of nodulation and lay a foundation for engineering of RNS traits in agriculturally important crops. 展开更多
关键词 nitrogen-fixing root-nodule symbiosis two competing hypotheses PHYLOGENOMICS phylotranscrip-tomics conserved non-coding elements convergence deep homology
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The crucial role of surveillance in disease outbreak control:a comprehensive review
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作者 Gehendra Mahara Reg Bhandari Dandan Zhou 《汕头大学医学院学报》 2024年第3期187-192,共6页
Surveillance systems are vital for detecting,managing,and mitigating infectious disease outbreaks.This review highlights the importance of modern technologies like AI and big data in enhancing surveillancecapabilities... Surveillance systems are vital for detecting,managing,and mitigating infectious disease outbreaks.This review highlights the importance of modern technologies like AI and big data in enhancing surveillancecapabilities.It underscores the need for global collaboration and examines the role of surveillance in diseases likeinfluenza,Ebola,and COVID-19.Technological innovations such as geospatial mapping and wearable healthdevices are transforming disease control,though they raise ethical concerns about privacy.Continuousadvancements and ethical safeguards are crucial for effective surveillance and global health protection. 展开更多
关键词 disease surveillance early detection global collaboration technological advancements ethical considerations
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Evaluation of Particle Properties of MgO/TiO2 Material by Monte Carlo Simulation Method
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作者 Koffi N’guessan Placide Gabin Allangba Yves Kily Hervé Fagnidi +2 位作者 Hermann N’guessan Zié Traoré Koffi Arnaud Kamenan 《Journal of Materials Science and Chemical Engineering》 2024年第2期49-60,共12页
The simulation by the Monte Carlo method executed by the software PyPENELOPE proved effective to specify the particle propagation characteristics by calculating the absorption fractions, backscattering and transmissio... The simulation by the Monte Carlo method executed by the software PyPENELOPE proved effective to specify the particle propagation characteristics by calculating the absorption fractions, backscattering and transmission of electrons and secondary photons under the incidence of 0.5 to 20 KeV range of primary electrons. More than 99.9% of the primary electrons were transmitted in the 125 nm thick MgO/TiO<sub>2</sub> material at 20 KeV. This occurred because several interactions took place in the transmitted primary irradiation such as characteristic, fluorescence, and bremsstrahlung produced when of the occupation of the KL3, KL2, KM3, and KM2 shell and sub-shell of titanium and magnesium which are the elements with a high atomic number in the material. The transmission particle characteristic of this material is therefore an indicator capable of improving the electrical performance and properties of the sensor. 展开更多
关键词 Monte Carlo PyPENELOPE Primary Electrons Transmission MgO/TiO2
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Spatial pattern of impervious surfaces and their impacts on land surface temperature in Beijing,China 被引量:48
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作者 XIAO Rong-bo OUYANG Zhi-yun +3 位作者 ZHENG Hua LI Wei-feng SCHIENKE Erich W WANG Xiao-ke 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第2期250-256,共7页
Land surface temperature (LST), which is heavily influenced by urban surface structures, is a significant parameter in urban environmental analysis. This study examined the effect impervious surfaces (IS) spatial ... Land surface temperature (LST), which is heavily influenced by urban surface structures, is a significant parameter in urban environmental analysis. This study examined the effect impervious surfaces (IS) spatial patterns have on LST in Beijing, China. A classification and regression tree model (CART) was adopted to estimate IS as a continuous variable using Landsat images from two seasons combined with QuickBird. LST was retrieved from the Landsat Thematic Mapper (TM) image to examine the relationships between IS and LST. The results revealed that CART was capable of consistently predicting LST with acceptable accuracy (correlation coefficient of 0.94 and the average error of 8.59%). Spatial patterns of IS exhibited changing gradients across the various urban-rural transects, with LST values showing a concentric shape that increased as you moved from the outskirts towards the downtown areas. Transect analysis also indicated that the changes in both IS and LST patterns were similar at various resolution levels, which suggests a distinct linear relationship between them. Results of correlation analysis further showed that IS tended to be positively correlated with LST, and that the correlation coefficients increased from 0.807 to 0.925 with increases in IS pixel size. The findings identified in this study provide a theoretical basis for improving urban planning efforts to lessen urban temperatures and thus dampen urban heat island effects. 展开更多
关键词 urban heat islands urban land cover normalized difference vegetation index (NDVI) climate mitigation regression tree
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Genetic algorithm and particle swarm optimization tuned fuzzy PID controller on direct torque control of dual star induction motor 被引量:13
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作者 BOUKHALFA Ghoulemallah BELKACEM Sebti +1 位作者 CHIKHI Abdesselem BENAGGOUNE Said 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第7期1886-1896,共11页
This study presents analysis, control and comparison of three hybrid approaches for the direct torque control (DTC) of the dual star induction motor (DSIM) drive. Its objective consists of combining three different he... This study presents analysis, control and comparison of three hybrid approaches for the direct torque control (DTC) of the dual star induction motor (DSIM) drive. Its objective consists of combining three different heuristic optimization techniques including PID-PSO, Fuzzy-PSO and GA-PSO to improve the DSIM speed controlled loop behavior. The GA and PSO algorithms are developed and implemented into MATLAB. As a result, fuzzy-PSO is the most appropriate scheme. The main performance of fuzzy-PSO is reducing high torque ripples, improving rise time and avoiding disturbances that affect the drive performance. 展开更多
关键词 dual star induction motor drive direct torque control particle swarm optimization (PSO) fuzzy logic control genetic algorithms
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