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基于YOLOv7的木材缺陷检测模型Wood-Net的研究
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作者 王正 江莺 +3 位作者 严飞 孙佑鹏 张园 张柳磊 《林业工程学报》 CSCD 北大核心 2024年第1期132-140,共9页
为改善利用人工方式识别木材缺陷存在的效率低、人工成本高的问题,同时实现在木材加工过程中使用新兴方式对不同的缺陷进行快速准确检测以提高木材利用率,针对现有的目标检测网络在木材缺陷检测方面存在诸如检测精度低、报错率高以及识... 为改善利用人工方式识别木材缺陷存在的效率低、人工成本高的问题,同时实现在木材加工过程中使用新兴方式对不同的缺陷进行快速准确检测以提高木材利用率,针对现有的目标检测网络在木材缺陷检测方面存在诸如检测精度低、报错率高以及识别种类少等局限,设计了用于木材缺陷检测的深度学习网络Wood-Net。Wood-Net将注意力机制ECA(efficient channel attention module)引入YOLOv7的主干网络,以便更好地区分木材缺陷之间的细微差别;将ECA与Res2Net结合后形成ECA-Res2Net模块,ECA-Res2Net模块克服了单纯的Res2Net跨通道交流能力不足的问题,增强了网络对更细粒度特征的提取能力;将ECA-Res2Net模块与SPPCSPC(spatial pyramid pooling and channel spatial pyramid convolution)并联形成ResSPPCSPC模块,增加了描述图像本身特征数量的能力,由此构成新方法Wood-Net。本研究将准确度、召回值、mAP@0.5以及mAP@0.5∶mAP@0.95 4个数值作为系统性能的评价指标。利用自建数据集训练Wood-Net,得到试验数据。试验结果表明:Wood-Net模型比基准模型YOLOv7在木材优选上精确率提高了4.52%,mAP@0.5∶mAP@0.95提高了6.62%;比基准模型YOLOv5s在木材优选上精确率提高了6.79%,mAP@0.5∶mAP@0.95提高了5.67%。ECA注意力机制能够有效提升E-ELAN的通道间信息交互能力;Res2Net模块具有很强的细粒度特征提取能力,在网络中引入Res2Net模块后,网络各项性能指标收敛速度快,在Res2Net中加入ECA后能够使单纯的Res2Net考虑多通道特征之间的关系,完成信息融合,提高检测性能。 展开更多
关键词 wood-Net 木材优选 ECA-Res2Net ECA Res2Net
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Physicomechanical Properties of Sustainable Wood Plastic Composites of Tropical Sawdust and Thermoplastic Waste for Possible Utilization in the Wood Industry
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作者 Jude I. Duruaku Patrick A. C. Okoye +3 位作者 Theresa U. Onuegbu Valentine I. Onwukeme Nkechi H. Okoye Joseph O. Nwadiogbu 《Journal of Sustainable Bioenergy Systems》 2023年第4期149-171,共23页
This work investigated and quantified the physicomechanical properties of flat-pressed wood plastic composites produced with recycled polyethylene terephthalate, recycled polyethylene and sawdust derived from selected... This work investigated and quantified the physicomechanical properties of flat-pressed wood plastic composites produced with recycled polyethylene terephthalate, recycled polyethylene and sawdust derived from selected tropical timbers, namely, Nauclea diderrichii, Brachystegia eurycoma, Erythrophleum suaveolens and Prosopis africana, for possible utilization in the wood industry. The compounding of the polymer blends of the precursor plastics, namely recycled PET (rPET) and recycled PE (rPE) with the sawdust (SD) from the selected timbers to produce the desired wood rPET/rPE composites was carried out via the flat press method. The characterization of the physicomechanical properties of the wood plastic composites (WPCs) produced, such as the density, hardness, flexural strength, ultimate tensile strength, elongation %, thickness swelling and water absorption capacity was carried out using methods based mainly on the European Committee for Standardization (CEN) and the American Society for Testing Materials (ASTM) standards. The results of the investigation on the resultant composites indicated that changes in the SD content affected the density of flat-pressed WPCs in line with literature. Generally, it was observed that as wood dust increased and PET content decreased, the density of composites decreased with some deviations as expected probably due to the anisotropic nature of the wood fillers. The analysis of variance (ANOVA) revealed that there was a statistically significant variation in the wood composites of Nuclea diderichii based on the physicomechanical values as the p-value (0.020) obtained was less than the critical level of α = 0.05. It was also observed that the composite, Wood 1 Sample 5 (W<sub>1</sub>S<sub>5</sub>) which was composed of 40% rPE, 40% rPET and 20% SD (derived from Nuclea diderichii), had the highest percentage elongation (26.84%);the highest flexural strength (14.995 N/mm<sup>2</sup>) and possibly the least carbon footprint in the environment. These properties of W<sub>1</sub>S<sub>5</sub> suggest that it could therefore be the best option for the production of building materials like ceiling boards or floor skirting in the wood plastic composite industry. The results of these investigations have therefore indicated that the fabrication of WPCs from sawdust and rPET/rPE was technically feasible and had prospects for large scale production in the wood industry. 展开更多
关键词 wood plastic Composites Density Water Absorption Capacity CELLULOSE Sustainability RECYCLE Waste
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3'-Deoxyadenosin alleviates methamphetamine-induced aberrant synaptic plasticity and seeking behavior by inhibiting the NLRP3 inflammasome 被引量:1
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作者 Yize Qi Yao Zhou +8 位作者 Jiyang Li Fangyuan Zhu Gengni Guo Can Wang Man Yu Yijie Wang Tengfei Ma Shanwu Feng Li Zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2270-2280,共11页
Methamphetamine addiction is a brain disorder characterized by persistent drug-seeking behavior, which has been linked with aberrant synaptic plasticity. An increasing body of evidence suggests that aberrant synaptic ... Methamphetamine addiction is a brain disorder characterized by persistent drug-seeking behavior, which has been linked with aberrant synaptic plasticity. An increasing body of evidence suggests that aberrant synaptic plasticity is associated with the activation of the NOD-like receptor family pyrin domain containing-3(NLRP3) inflammasome. 3′-Deoxyadenosin, an active component of the Chinese fungus Cordyceps militaris, has strong anti-inflammatory effects. However, whether 3′-deoxyadenosin attenuates methamphetamine-induced aberrant synaptic plasticity via an NLRP3-mediated inflammatory mechanism remains unclear. We first observed that 3′-deoxyadenosin attenuated conditioned place preference scores in methamphetamine-treated mice and decreased the expression of c-fos in hippocampal neurons. Furthermore, we found that 3′-deoxyadenosin reduced the aberrant potentiation of glutamatergic transmission and restored the methamphetamine-induced impairment of synaptic plasticity. We also found that 3′-deoxyadenosin decreased the expression of NLRP3 and neuronal injury. Importantly, a direct NLRP3 deficiency reduced methamphetamine-induced seeking behavior, attenuated the impaired synaptic plasticity, and prevented neuronal damage. Finally, NLRP3 activation reversed the effect of 3′-deoxyadenosin on behavior and synaptic plasticity, suggesting that the anti-neuroinflammatory mechanism of 3′-deoxyadenosin on aberrant synaptic plasticity reduces methamphetamine-induced seeking behavior. Taken together, 3′-deoxyadenosin alleviates methamphetamine-induced aberrant synaptic plasticity and seeking behavior by inhibiting the NLRP3 inflammasome. 展开更多
关键词 3′-deoxyadenosin hippocampus long-term potentiation METHAMPHETAMINE NOD-like receptor family pyrin domain containing-3(NLRP3)inflammasome synaptic plasticity
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Recent Advance in Synaptic Plasticity Modulation Techniques for Neuromorphic Applications
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作者 Yilin Sun Huaipeng Wang Dan Xie 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期403-434,共32页
Manipulating the expression of synaptic plasticity of neuromorphic devices provides fascinating opportunities to develop hardware platforms for artifi-cial intelligence.However,great efforts have been devoted to explo... Manipulating the expression of synaptic plasticity of neuromorphic devices provides fascinating opportunities to develop hardware platforms for artifi-cial intelligence.However,great efforts have been devoted to exploring biomimetic mechanisms of plasticity simulation in the last few years.Recent progress in various plasticity modulation techniques has pushed the research of synaptic electronics from static plasticity simulation to dynamic plasticity modulation,improving the accuracy of neuromorphic computing and providing strategies for implementing neuromorphic sensing functions.Herein,several fascinating strategies for synap-tic plasticity modulation through chemical techniques,device structure design,and physical signal sensing are reviewed.For chemical techniques,the underly-ing mechanisms for the modification of functional materials were clarified and its effect on the expression of synaptic plasticity was also highlighted.Based on device structure design,the reconfigurable operation of neuromorphic devices was well demonstrated to achieve programmable neuromorphic functions.Besides,integrating the sensory units with neuromorphic processing circuits paved a new way to achieve human-like intelligent perception under the modulation of physical signals such as light,strain,and temperature.Finally,considering that the relevant technology is still in the basic exploration stage,some prospects or development suggestions are put forward to promote the development of neuromorphic devices. 展开更多
关键词 plasticity modulation Dynamic plasticity Chemical techniques Programmable operation Neuromorphic sensing
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Wood灯检查在白癜风治疗期间不同复色模式观察研究中的应用
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作者 金伟梅 马杰 +2 位作者 索翠平 车旭 赵建斌 《中国美容医学》 CAS 2024年第5期103-107,共5页
目的:通过观察Wood灯下白癜风患者治疗过程中皮损的复色模式,探究不同复色模式的相关影响因素,分析评估不同复色模式间的疗效差异。方法:收集选取2021年8月-2022年8月笔者医院就诊的90例(170块),采集患者基本信息及病情相关指标。治疗后... 目的:通过观察Wood灯下白癜风患者治疗过程中皮损的复色模式,探究不同复色模式的相关影响因素,分析评估不同复色模式间的疗效差异。方法:收集选取2021年8月-2022年8月笔者医院就诊的90例(170块),采集患者基本信息及病情相关指标。治疗后,观察Wood灯下皮损复色模式,将复色模式与收集指标进行统计分析,筛选出差异有统计学意义的指标后,采用Logistic回归分析阳性指标与复色模式的相关性。并将Wood灯下观察的皮损面积作为疗效判定标准,分析对比不同复色模式间的疗效差异。结果:One-way ANOVA分析、χ^(2)检验显示白癜风疾病分期、皮损部位、治疗方式与皮损复色模式有关(P<0.05)。Logistic回归分析显示:治疗方式与复色模式存在相关性(P<0.05)。不同复色模式达到有效复色面积的时间比较,差异有统计学意义(H=8.04,P<0.05)。结论:通过观察Wood灯下白癜风患者治疗过程中皮损的复色模式发现,治疗方式可能是白癜风皮损复色模式的决定因素;不同复色模式之间的复色速度存在差异,可作为临床医师调整治疗方案的参考依据。 展开更多
关键词 白癜风 复色模式 治疗方式 复色速度 wood
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Perspectives in human brain plasticity sparked by glioma invasion:from intraoperative(re)mappings to neural reconfigurations
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作者 Sam Ng Hugues Duffau Guillaume Herbet 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期947-948,共2页
Exploring the aptitude of the human brain to compensate functional consequences of a lesion damaging its structural architecture is a key challenge to improve patient care in various neurological diseases,to optimize ... Exploring the aptitude of the human brain to compensate functional consequences of a lesion damaging its structural architecture is a key challenge to improve patient care in various neurological diseases,to optimize neuroscientifically-informed strategies of postlesional rehabilitation,and ultimately to develop innovative neuro-regenerative therapies.The term‘plasticity’,initially referring to the intrinsic propensity of neurons to modulate their synaptic transmission in a learning situation,was progressively transposed to brain injury research and clinical neurosciences.Indeed,in the event of brain damage,adaptive mechanisms of compensation allow a partial reshaping of the structure and activities of the central nervous system,thus permitting to some extent the maintenance of brain functions. 展开更多
关键词 plasticITY figuration consequences
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Mitochondrial recruitment in myelin:an anchor for myelin dynamics and plasticity?
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作者 Jean-David M.Gothié Timothy E.Kennedy 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1401-1402,共2页
Optimal propagation of neuronal electrical impulses depends on the insulation of axons by myelin,produced in the central nervous system by oligodendrocytes.Myelin is an extension of the oligodendrocyte plasma membrane... Optimal propagation of neuronal electrical impulses depends on the insulation of axons by myelin,produced in the central nervous system by oligodendrocytes.Myelin is an extension of the oligodendrocyte plasma membrane,which wraps around an axon to form a compact multi-layered sheath.Myelin is composed of a substantially higher proportion of lipids compared to other biological membranes and enriched in a small number of specialized proteins. 展开更多
关键词 plasticITY insulation DYNAMICS
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Glial progenitor heterogeneity and plasticity in the adult spinal cord
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作者 Haichao Wei Jia Qian Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2567-2568,共2页
Glial progenitor cells were reported to have the capacity to generate various types of cells in both the central nervous system(CNS)and peripheral nervous system.Glial progenitor cells can respond to diverse environme... Glial progenitor cells were reported to have the capacity to generate various types of cells in both the central nervous system(CNS)and peripheral nervous system.Glial progenitor cells can respond to diverse environmental signals and transform into distinct populations,each serving specific functions.Notably,the adult spinal cord hosts various populations of glial progenitors,a region integral to the central nervous system.During development,glial progenitors express glial fibrillary acidic protein(GFAP;Dimou and Gotz,2014).However,the specific identities of GFAP-expressing progenitors in the adult spinal cord were not thoroughly investigated. 展开更多
关键词 functions plasticITY thoroughly
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From mice to humans:a need for comparable results in mammalian neuroplasticity
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作者 Marco Ghibaudi Enrica Boda Luca Bonfanti 《Neural Regeneration Research》 SCIE CAS 2025年第2期464-466,共3页
Brain plasticity-A universal tool with many variations:The study of brain plasticity has been gaining interest since almost a century and has now reached a huge amount of information(>80,000 results in PubMed).Over... Brain plasticity-A universal tool with many variations:The study of brain plasticity has been gaining interest since almost a century and has now reached a huge amount of information(>80,000 results in PubMed).Overall,different types of plasticity,including stem cell-driven genesis of new neurons(adult neurogenesis),cells in arrested maturation(dormant neurons),neuro-glial and synaptic plasticity,can coexist and contribute to grant plastic changes in the brain,from a cellular to system level(Benedetti and Couillard-Despres,2022;Bonfanti et al.,2023). 展开更多
关键词 plasticITY al. ARREST
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Enhancing wood efficiency through comprehensive wood flow analysis:Methodology and strategic insights
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作者 Ruisheng Wang Peer Haller 《Forest Ecosystems》 SCIE CSCD 2024年第2期172-183,共12页
Wood,an essential natural resource in human civilization,remains widely used despite advances in technology and material substitution.The surge in greenhouse gas emissions and environmental concerns accentuates the ne... Wood,an essential natural resource in human civilization,remains widely used despite advances in technology and material substitution.The surge in greenhouse gas emissions and environmental concerns accentuates the need for optimizing wood utilization.Material flow analysis is a powerful tool for tracking material flows and stocks,aiding resource management and environmental decision-making.However,the full extent of its methodological dimensions,particularly within the context of the wood supply chain,remains relatively unexplored.In this study,we delve into the existing literature on wood flow analysis,discussing its primary objectives,materials involved,temporal and spatial scales,data sources,units,and conversion factors.Additionally,data uncertainty,data reconciliation and crucial assumptions in material flow analysis are highlighted in this paper.Key findings reveal the significance of wood cascading and substitution effects by replacing non-wood materials,where they can reduce greenhouse gas emissions more than the natural carbon sink of forests and wood products.The immediate impact of short-term wood cascading might not be as robust as the substitution effect,with energy substitution showcasing better results than material substitution.However,it's crucial to note that these conclusions could experience significant reversal from a long-term and global perspective.Strategies for improving wood efficiency involve maximizing material use,advancing construction technologies,extending product lifespans,promoting cascade use,and optimizing energy recovery processes.The study underscores the need for standardized approaches in wood flow analysis and emphasizes the potential of wood efficiency strategies in addressing environmental challenges. 展开更多
关键词 Material flow analysis wood METHODOLOGY Cascade use Substitution effects
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Evolutionary history shapes variation of wood density of tree species across the world
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作者 Fangbing Li Hong Qian +7 位作者 Jordi Sardans Dzhamal Y.Amishev Zixuan Wang Changyue Zhang Tonggui Wu Xiaoniu Xu Xiao Tao Xingzhao Huang 《Plant Diversity》 SCIE CAS CSCD 2024年第3期283-293,共11页
The effect of evolutionary history on wood density variation may play an important role in shaping variation in wood density,but this has largely not been tested.Using a comprehensive global dataset including 27,297 m... The effect of evolutionary history on wood density variation may play an important role in shaping variation in wood density,but this has largely not been tested.Using a comprehensive global dataset including 27,297 measurements of wood density from 2621 tree species worldwide,we test the hypothesis that the legacy of evolutionary history plays an important role in driving the variation of wood density among tree species.We assessed phylogenetic signal in different taxonomic(e.g.,angiosperms and gymnosperms)and ecological(e.g.,tropical,temperate,and boreal)groups of tree species,explored the biogeographical and phylogenetic patterns of wood density,and quantified the relative importance of current environmental factors(e.g.,climatic and soil variables)and evolutionary history(i.e.,phylogenetic relatedness among species and lineages)in driving global wood density variation.We found that wood density displayed a significant phylogenetic signal.Wood density differed among different biomes and climatic zones,with higher mean values of wood density in relatively drier regions(highest in subtropical desert).Our study revealed that at a global scale,for angiosperms and gymnosperms combined,phylogeny and species(representing the variance explained by taxonomy and not direct explained by long-term evolution process)explained 84.3%and 7.7%of total wood density variation,respectively,whereas current environment explained 2.7%of total wood density variation when phylogeny and species were taken into account.When angiosperms and gymnosperms were considered separately,the three proportions of explained variation are,respectively,84.2%,7.5%and 6.7%for angiosperms,and 45.7%,21.3%and 18.6%for gymnosperms.Our study shows that evolutionary history outpaced current environmental factors in shaping global variation in wood density. 展开更多
关键词 wood density PHYLOGENY ANGIOSPERMS GYMNOSPERMS Climate factors Biophysical parameters
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Wood By-Products as UV Protection:A Consequence Review
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作者 Naglaa Salem El‑Sayed Mohamed Hasanin Samir Kamel 《Journal of Renewable Materials》 EI CAS 2024年第4期699-720,共22页
In recent decades,the ozone layer has suffered considerable damage,increasing the entry of ultraviolet(UV)light into the atmosphere and reaching the earth’s surface,negatively affecting life.Accordingly,researchers a... In recent decades,the ozone layer has suffered considerable damage,increasing the entry of ultraviolet(UV)light into the atmosphere and reaching the earth’s surface,negatively affecting life.Accordingly,researchers aimed to solve this problem by synthesizing advanced UV-shielding materials.On the other hand,developing an easy and green strategy to prepare functional materials with outstanding properties based on naturally abundant and environmentally friendly raw materials is highly desirable for sustainable development.Because biomass-derived materials are sustainable and biodegradable,they present a promising substitute for petroleum-based polymers.The three main structural constituents of the plant biomass-based materials that are naturally available are cellulose,hemicellulose,and lignin.This review details current developments using wood-based products such as cellulose,hemicellulose,and lignin in UV-shielding applications.It will start with assembling the structure and chemistry of cellulose,hemicellulose,and lignin,followed by their contributions to preparing UV-shielding materials.Finally,it will briefly discuss the different processing methods for the design of UV-shielding materials.The wood by-products offer additional opportunities to use the whole tree harvest. 展开更多
关键词 UV-SHIELDING wood cellulose LIGNIN HEMICELLULOSE sunlight protection
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Age-related differences in long-term potentiation-like plasticity and shortlatency afferent inhibition and their association with cognitive function
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作者 Qian Lu Sisi Huang +7 位作者 Tianjiao Zhang Jie Song Manyu Dong Yilun Qian Jing Teng Tong Wang Chuan He Ying Shen 《General Psychiatry》 CSCD 2024年第1期73-82,共10页
Background The neurophysiological differences in cortical plasticity and cholinergic system function due to ageing and their correlation with cognitive function remain poorly understood.Aims To reveal the differences ... Background The neurophysiological differences in cortical plasticity and cholinergic system function due to ageing and their correlation with cognitive function remain poorly understood.Aims To reveal the differences in long-term potentiation(LTP)-like plasticity and short-latency afferent inhibition(SAl)between older and younger individuals,alongside their correlation with cognitive function using transcranial magnetic stimulation(TMS).Methods The cross-sectional study involved 31 younger adults aged 18-30 and 46 older adults aged 60-80.All participants underwent comprehensive cognitive assessments and a neurophysiological evaluation based on TMS.Cognitive function assessments included evaluations of global cognitive function,language,memory and executive function.The neurophysiological assessment included LTP-like plasticity and SAl.Results The findings of this study revealed a decline in LTP among the older adults compared with the younger adults(wald χ^(2)=3.98,p=0.046).Subgroup analysis further demonstrated a significant reduction in SAl level among individuals aged 70-80 years in comparison to both the younger adults(SAI(N20)):(t=-3.37,p=0.018);SAl(N20+4):(t=-3.13,p=0.038)and those aged 60-70(SAl(N20)):(t=3.26,p=0.025);SAl(N20+4):(t=-3.69,p=0.006).Conversely,there was no notable difference in SAl level between those aged 60-70 years and the younger group.Furthermore,after employing the Bonferroni correction,the correlation analysis revealed that only the positive correlation between LTP-like plasticity and language function(r=0.61,p<0.001)in the younger group remained statistically significant.Conclusions During the normal ageing process,a decline in synaptic plasticity may precede cholinergic system dysfunction.In individuals over 60 years of age,there is a reduction in LTP-like plasticity,while a decline in cholinergic system function is observed in those over 70.Thus,the cholinergic system may play a vital role in preventing cognitive decline during normal ageing.In younger individuals,LTP-like plasticity might represent a potential neurophysiological marker for language function. 展开更多
关键词 function YOUNGER plasticITY
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Impact of Plastic Waste on the Human Health in Low-Income Countries: A Systematic Review
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作者 Ramde Wendkoaghenda Sophie Gbandama Koffi Kouame Pacome +5 位作者 Gansore Aminata Camara Kelety Tolno Barthélemy Assogba Ange Wenceslas Vinciale Niare Boubacar Patrice Ngangue 《Journal of Environmental Protection》 2024年第5期572-595,共24页
Background: Plastic pollution is the accumulation of waste composed of plastic and its derivatives all over the environment. Whether in the form of visible garbage or microparticles, as it slowly degrades, plastic pol... Background: Plastic pollution is the accumulation of waste composed of plastic and its derivatives all over the environment. Whether in the form of visible garbage or microparticles, as it slowly degrades, plastic pollution poses significant threats to terrestrial and aquatic habitats and the wildlife that call them home, whether through ingestion, entanglement or exposure to the chemicals contained in the material. Unfortunately, there is a lack of documentation on the impact of plastic waste on human health in low- and middle-income countries (LMICs). Methods: We searched five electronic databases (PubMed, Embase, Global Health, CINAHL and Web of Science) and gray literature, following the preferred reporting elements for systematic reviews and meta-analyses (PRISMA), for the impact of plastic waste on human health in developing countries. We included quantitative and qualitative studies written in English and French. We assessed the quality of the included articles using the Mixed Methods Appraisal tool (MMAT). Results: A total of 3779 articles were initially identified by searching electronic databases. After eliminating duplicates, 3167 articles were reviewed based on title and abstract, and 26 were selected for full-text review. Only three articles were retained. The three articles dealt with practices likely to lead to oral exposure to plastic chemicals in human health, as well as the level of awareness of participants concerning the possible impact of plastic on human health, namely, the use of plastic baby bottles, the use of microwaves to cook food and reheat precooked food, the use of plastic bottles to store water in the refrigerator, water purifier containers with plastic bodies and plastic lunch boxes, the reuse of plastic bags and the inadequacy of treatment facilities. Conclusion: Plastic waste poses different risks to human health at every stage of its life cycle. Hence, strategies must be adopted to raise public awareness of the dangers of plastic waste to their health. Trial registration: The review protocol is registered in the PROSPERO international prospective register of systematic reviews (ID = CRD42023409087). 展开更多
关键词 Human Population plastic Waste Health Impact Low-Income-Countries (Humans Iatrogenic Disease plasticS POLICY RECYCLING Waste Management)
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Configuring single-layer MXene nanosheet onto natural wood fiber via C-Ti-C covalent bonds for high-stability Li-S batteries
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作者 Yangyang Chen Yu Liao +5 位作者 Ying Wu Lei Li Zhen Zhang Sha Luo Yiqiang Wu Yan Qing 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期701-711,I0016,共12页
Lithium-sulfur batteries(LSBs)are considered promising candidates for next-generation battery technologies owing to their outstanding theoretical energy density and cost-effectiveness.However,the low conductivity and ... Lithium-sulfur batteries(LSBs)are considered promising candidates for next-generation battery technologies owing to their outstanding theoretical energy density and cost-effectiveness.However,the low conductivity and polysulfide shuttling effect of S cathodes severely hamper the practical performance of LSBs.Herein,in situ-generated single layer MXene nanosheet/hierarchical porous carbonized wood fiber(MX/PCWF)composites are prepared via a nonhazardous eutectic activation strategy coupled with pyrolysis-induced gas diffusion.The unique architecture,wherein single layer MXene nanosheets are constructed on carbonized wood fiber walls,ensures rapid polysulfide conversion and continuous electron transfer for redox reactions.The C-Ti-C bonds formed between MXene and PCWF can considerably expedite the conversion of polysulfides,effectively suppressing the shuttle effect.An impressive capacity of 1301.1 m A h g^(-1)at 0.5 C accompanied by remarkable stability is attained with the MX/PCWF host,as evidenced by the capacity maintenance of 722.6 m A h g^(-1)after 500 cycles.Notably,the MX/PCWF/S cathode can still deliver a high capacity of 886.8 m A h g^(-1)at a high S loading of 5.6 mg cm^(-2).The construction of two-dimensional MXenes on natural wood fiber walls offers a competitive edge over S-based cathode materials and demonstrates a novel strategy for developing high-performance batteries. 展开更多
关键词 Lithium-sulfur batteries S cathodes MXene nanosheets wood fiber C-Ti-C bonds
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Relating estimates of wood properties of birch to stem form, age and species
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作者 Grace Jones Maria Ulan +2 位作者 Mateusz Liziniewicz Johan Lindeberg Stergios Adamopoulos 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期1-11,共11页
Birch has long suffered from a lack of active forest management,leading many researchers to use mate-rial without a detailed management history.Data collected from three birch(Betula pendula Roth,B.pubescens Ehrh.)sit... Birch has long suffered from a lack of active forest management,leading many researchers to use mate-rial without a detailed management history.Data collected from three birch(Betula pendula Roth,B.pubescens Ehrh.)sites in southern Sweden were analyzed using regression analysis to detect any trends or differences in wood proper-ties that could be explained by stand history,tree age and stem form.All sites were genetics trials established in the same way.Estimates of acoustic velocity(AV)from non-destructive testing(NDT)and predicted AV had a higher correlation if data was pooled across sites and other stem form factors were considered.A subsample of stems had radial profiles of X-ray wood density and ring width by year created,and wood density was related to ring number from the pith and ring width.It seemed likely that wood density was negatively related to ring width for both birch species.Linear models had slight improvements if site and species were included,but only the youngest site with trees at age 15 had both birch species.This paper indicated that NDT values need to be considered separately,and any predictive models will likely be improved if they are specific to the site and birch species measured. 展开更多
关键词 Acoustic velocity Non-destructive testing Predictive models Regression analysis wood density
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Green synthesis of ZSM-5 using silica fume and catalytic co-cracking of lignin and plastics for production of monocyclic aromatics
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作者 Hongbing Fu Yufei Gu +7 位作者 Tianhua Gao Fuwei Li Hengshuo Gu Hucheng Ge Yuke Liu Zhixia Li Hongfei Lin Jiangfei Cao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期92-105,共14页
ZSM-5 with hierarchical pore structure was synthesized by a simple two-step hydrothermal crystallization from silica fume without using any organic ammonium templates.The synthesized ZSM-5 were oval shaped particles w... ZSM-5 with hierarchical pore structure was synthesized by a simple two-step hydrothermal crystallization from silica fume without using any organic ammonium templates.The synthesized ZSM-5 were oval shaped particles with a particle size about 2.0 μm and weak acid-dominated with proper Brønsted(B)and Lewis(L)acid sites.The ZSM-5 was used for catalytic co-cracking of n-octane and guaiacol,lowdensity polyethylene(LDPE)and alkali lignin(AL)to enhance the production of benzene,toluene,ethylbenzene and xylene(BTEX).The most significant synergistic effect occurred at n-octane/guaiacol at 1:1 and LDPE/AL at 1:3,under the condition,the achieved BTEX selectivity were 24%and 33%(mass)higher than the calculated values(weighted average).The highest BTEX selectivity reached 88.5%,which was 3.7%and 54.2%higher than those from individual cracking LDPE and AL.The synthesized ZSM-5 exhibited superior catalytic performance compared to the commercial ZSM-5,indicating potential application prospect. 展开更多
关键词 Silica fume ZSM-5 Catalytic co-cracking plasticS LIGNIN
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Leakage Proof,Flame-Retardant,and Electromagnetic Shield Wood Morphology Genetic Composite Phase Change Materials for Solar Thermal Energy Harvesting
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作者 Yuhui Chen Yang Meng +7 位作者 Jiangyu Zhang Yuhui Xie Hua Guo Mukun He Xuetao Shi Yi Mei Xinxin Sheng Delong Xie 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期99-120,共22页
Phase change materials(PCMs)offer a promising solution to address the challenges posed by intermittency and fluctuations in solar thermal utilization.However,for organic solid-liquid PCMs,issues such as leakage,low th... Phase change materials(PCMs)offer a promising solution to address the challenges posed by intermittency and fluctuations in solar thermal utilization.However,for organic solid-liquid PCMs,issues such as leakage,low thermal conductivity,lack of efficient solar-thermal media,and flamma-bility have constrained their broad applications.Herein,we present an innova-tive class of versatile composite phase change materials(CPCMs)developed through a facile and environmentally friendly synthesis approach,leveraging the inherent anisotropy and unidirectional porosity of wood aerogel(nanowood)to support polyethylene glycol(PEG).The wood modification process involves the incorporation of phytic acid(PA)and MXene hybrid structure through an evaporation-induced assembly method,which could impart non-leaking PEG filling while concurrently facilitating thermal conduction,light absorption,and flame-retardant.Consequently,the as-prepared wood-based CPCMs showcase enhanced thermal conductivity(0.82 W m^(-1)K^(-1),about 4.6 times than PEG)as well as high latent heat of 135.5 kJ kg^(-1)(91.5%encapsula-tion)with thermal durability and stability throughout at least 200 heating and cooling cycles,featuring dramatic solar-thermal conversion efficiency up to 98.58%.In addition,with the synergistic effect of phytic acid and MXene,the flame-retardant performance of the CPCMs has been significantly enhanced,showing a self-extinguishing behavior.Moreover,the excellent electromagnetic shielding of 44.45 dB was endowed to the CPCMs,relieving contemporary health hazards associated with electromagnetic waves.Overall,we capitalize on the exquisite wood cell structure with unidirectional transport inherent in the development of multifunctional CPCMs,showcasing the operational principle through a proof-of-concept prototype system. 展开更多
关键词 wood PCMs MXene Solar thermal storage and conversion FLAME-RETARDANT Electromagnetic shielding
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Timing effect of high temperature exposure on the plasticity of internode and plant architecture in maize
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作者 Binbin Li Xianmin Chen +6 位作者 Tao Deng Xue Zhao Fang Li Bingchao Zhang Xin Wang Si Shen Shunli Zhou 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期551-565,共15页
The occurrence of high temperature(HT)in crop production is becoming more frequent and unpredictable with global warming,severely threatening food security.The state of an organ’s growth and development is largely de... The occurrence of high temperature(HT)in crop production is becoming more frequent and unpredictable with global warming,severely threatening food security.The state of an organ’s growth and development is largely determined by the temperature conditions it is exposed to over time.Maize is the main cereal crop,and its stem growth and plant architecture are closely related to lodging resistance,and especially sensitive to temperature.However,systematic research on the timing effect of HT on the sequentially developing internode and stem is currently lacking.To identify the timing effect of HT on the morphology and plasticity of the stem in maize,two hybrids(Zhengdan 958(ZD958),Xianyu 335(XY335))characterized by distinct morphological traits in the stem were exposed to a 7-day HT treatment from the V6 to V17 stages(Vn presents the vegetative stage with n leaves fully expanded)in 2019-2020.The results demonstrated that exposure to HT during V6-V12 accelerated the rapid elongation of stems.For instance,HT occurring at V7 and V12 specifically promoted the lengths and weights of the 3rd-5th and 9th-11th internodes,respectively.Meanwhile,HT slowed the growth of internodes adjacent to the promoted internodes.Interestingly,compared with control,the plant height was significantly increased soon after HT treatment,but the promotion effect became narrower at the subsequent flowering stage,demonstrating a self-adjusting mechanism in the maize plant in response to HT.Importantly,HT altered the plant architectures,including a rising of the ear position and increase in the ear position coefficient.XY335 exhibited greater sensitivity in stem development than ZD958 under HT treatment.These findings improve our systematic understanding of the plasticity of internode and plant architecture in response to the timing of HT exposure. 展开更多
关键词 MAIZE high temperature internode growth plasticITY plant architecture
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Estimating wood quality attributes from dense airborne LiDAR point clouds
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作者 Nicolas Cattaneo Stefano Puliti +1 位作者 Carolin Fischer Rasmus Astrup 《Forest Ecosystems》 SCIE CSCD 2024年第2期226-235,共10页
Mapping individual tree quality parameters from high-density LiDAR point clouds is an important step towards improved forest inventories.We present a novel machine learning-based workflow that uses individual tree poi... Mapping individual tree quality parameters from high-density LiDAR point clouds is an important step towards improved forest inventories.We present a novel machine learning-based workflow that uses individual tree point clouds from drone laser scanning to predict wood quality indicators in standing trees.Unlike object reconstruction methods,our approach is based on simple metrics computed on vertical slices that summarize information on point distances,angles,and geometric attributes of the space between and around the points.Our models use these slice metrics as predictors and achieve high accuracy for predicting the diameter of the largest branch per log (DLBs) and stem diameter at different heights (DS) from survey-grade drone laser scans.We show that our models are also robust and accurate when tested on suboptimal versions of the data generated by reductions in the number of points or emulations of suboptimal single-tree segmentation scenarios.Our approach provides a simple,clear,and scalable solution that can be adapted to different situations both for research and more operational mapping. 展开更多
关键词 UAV laser scanning wood quality Machine learning Point cloud metrics
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