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Deep Reinforcement Learning-Based Task Offloading and Service Migrating Policies in Service Caching-Assisted Mobile Edge Computing
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作者 Ke Hongchang Wang Hui +1 位作者 Sun Hongbin Halvin Yang 《China Communications》 SCIE CSCD 2024年第4期88-103,共16页
Emerging mobile edge computing(MEC)is considered a feasible solution for offloading the computation-intensive request tasks generated from mobile wireless equipment(MWE)with limited computational resources and energy.... Emerging mobile edge computing(MEC)is considered a feasible solution for offloading the computation-intensive request tasks generated from mobile wireless equipment(MWE)with limited computational resources and energy.Due to the homogeneity of request tasks from one MWE during a longterm time period,it is vital to predeploy the particular service cachings required by the request tasks at the MEC server.In this paper,we model a service caching-assisted MEC framework that takes into account the constraint on the number of service cachings hosted by each edge server and the migration of request tasks from the current edge server to another edge server with service caching required by tasks.Furthermore,we propose a multiagent deep reinforcement learning-based computation offloading and task migrating decision-making scheme(MBOMS)to minimize the long-term average weighted cost.The proposed MBOMS can learn the near-optimal offloading and migrating decision-making policy by centralized training and decentralized execution.Systematic and comprehensive simulation results reveal that our proposed MBOMS can converge well after training and outperforms the other five baseline algorithms. 展开更多
关键词 deep reinforcement learning mobile edge computing service caching service migrating
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Silicone oil migrating into the conjunctival space and orbit after surgery for an eye-penetrating injury:A case report
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作者 Ben-Liang Shu Hong-Yun Wu +4 位作者 Yu-Xiang Hu Jie Rao Bin Wei Qin-Yi Huang Xiao-Rong Wu 《World Journal of Clinical Cases》 SCIE 2024年第19期3950-3955,共6页
BACKGROUND We report a case of eye-penetrating injury in which a massive silicone oil migration into the patient’s subconjunctival space and orbit occurred after vitrectomy.CASE SUMMARY A 30-year-old male patient sou... BACKGROUND We report a case of eye-penetrating injury in which a massive silicone oil migration into the patient’s subconjunctival space and orbit occurred after vitrectomy.CASE SUMMARY A 30-year-old male patient sought medical attention at Ganzhou People’s Hospital after experiencing pain and vision loss in his left eye due to a nail wound on December 9,2023.Diagnosis of penetrating injury caused by magnetic foreign body retention in the left eye and hospitalization for treatment.On December 9,2023,pars plana vitrectomy was performed on the left eye for intraocular foreign body removal,abnormal crystal extraction,retinal photocoagulation.Owing to the discovery of retinal detachment at the posterior pole during surgery,silicone oil was injected to fill the vitreous body,following which upper conjunctival bubble-like swelling was observed.Postoperative orbital computed tomography(CT)review indicated migration of silicone oil to the subconjunctival space and orbit through a self-permeable outlet.On December 18,2023,the patient sought treatment at the First Affiliated Hospital of Nanchang University,China.The patient presented with a pronounced foreign body sensation following left eye surgery.On December 20,2023,the foreign body was removed from the left eye frame and an intraocular examination was conducted.The posterior scleral tear had closed,leading to termination of the surgical procedure following supplementary laser treatment around the tear.The patient reported a significant reduction in ocular surface symptoms just one day after surgery.Furthermore,a notable decrease in the migration of silicone oil was observed in orbital CT scans.CONCLUSION The timing of silicone oil injection for an eye-penetrating injury should be carefully evaluated to avoid the possibility of silicone oil migration. 展开更多
关键词 Silicone oils MIGRATION VITRECTOMY Eye injuries PENETRATING Case report
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Promoting Climate Change Havens in the United States and Globally for Migrating Populations
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作者 Elizabeth C. Hirschman Olivia Toomer 《Journal of Environmental Protection》 2023年第9期761-780,共20页
Appalachia has been identified as the largest Climate Change Haven in the continental United States and could serve as a refuge for millions of persons. This research presents a marketing plan for promoting migration ... Appalachia has been identified as the largest Climate Change Haven in the continental United States and could serve as a refuge for millions of persons. This research presents a marketing plan for promoting migration to the Appalachian Region using advertising and a website that communicates the desirable qualities of the area. Communications will first be directed toward the current residents of Appalachia (the Internal Market) in order to create enthusiasm for welcoming new arrivals. Then, promotional messages will be sent to prospective migrants seeking to escape the negative effects of climate change in the Southeast and Southwest of the United States and globally (the External Market). The approach used here may be applicable to Climate Change Havens across the globe. 展开更多
关键词 Climate Change Havens APPALACHIA Climate Change Migration Economic Rejuvenation Promotional Websites
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Unexpected divergence in magnetoreceptor MagR from robin and pigeon linked to two sequence variations 被引量:4
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作者 Shun Wang Peng Zhang +12 位作者 Fan Fei Tianyang Tong Xiujuan Zhou Yajie Zhou Jing Zhang Mengke Wei Yanqi Zhang Lei Zhang Yulong Huang Lin Zhang Xin Zhang Tiantian Cai Can Xie 《Zoological Research》 SCIE CSCD 2024年第1期69-78,共10页
Birds exhibit extraordinary mobility and remarkable navigational skills,obtaining guidance cues from the Earth’s magnetic field for orientation and long-distance movement.Bird species also show tremendous diversity i... Birds exhibit extraordinary mobility and remarkable navigational skills,obtaining guidance cues from the Earth’s magnetic field for orientation and long-distance movement.Bird species also show tremendous diversity in navigation strategies,with considerable differences even within the same taxa and among individuals from the same population.The highly conserved iron and iron-sulfur cluster binding magnetoreceptor(MagR)protein is suggested to enable animals,including birds,to detect the geomagnetic field and navigate accordingly.Notably,MagR is also implicated in other functions,such as electron transfer and biogenesis of iron-sulfur clusters,raising the question of whether variability exists in its biochemical and biophysical features among species,particularly birds.In the current study,we conducted a comparative analysis of MagR from two different bird species,including the migratory European robin(Erithacus rubecula)and the homing pigeon(Columba livia).Sequence alignment revealed an extremely high degree of similarity between the MagRs of these species,with only three sequence variations.Nevertheless,two of these variations underpinned significant differences in metal binding capacity,oligomeric state,and magnetic properties.These findings offer compelling evidence for the marked differences in MagR between the two avian species,potentially explaining how a highly conserved protein can mediate such diverse functions. 展开更多
关键词 Homing and migration Animal navigation Magnetoreceptor(MagR) Diverse navigation pattern Conserved protein
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Geochemical identification of a source rock affected by migrated hydrocarbons and its geological significance:Fengcheng Formation,southern Mahu Sag,Junggar Basin,NW China 被引量:2
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作者 Wen-Long Dang Gang Gao +5 位作者 Xin-Cai You Ke-Ting Fan Jun Wu De-Wen Lei Wen-Jun He Yong Tang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期100-114,共15页
The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu Sag.Crude oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of th... The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu Sag.Crude oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of the sag in the southern Mahu Sag.These crude oils originate from in-situ source rocks in shallowly buried areas and the inner deep sag.During migration,the crude oil from the inner deep sag affects the source rocks close to carrier beds,leading to changes in the organic geochemical characteristics of the source rocks.These changes might alter source rock evaluations and oil-source correlation.Based on data such as total organic carbon(TOC),Rock-Eval pyrolysis of source rocks,and gas chromatography-mass spectrometry(GC-MS)of the saturated fraction,and considering the geological characteristics of the study area,we define the identification characteristics of source rock affected by migrated hydrocarbons and establish the various patterns of influence that migrated hydrocarbons have on the source rock of the Fengcheng Formation in the southern Mahu Sag.The source rocks of the Fengcheng Formation are mostly fair to good,containing mainly Type II organic matter and being thermally mature enough to generate oil.Source rocks affected by migrated hydrocarbons exhibit relatively high hydrocarbon contents(S1/TOC>110 mg HC/g TOC,Extract/TOC>30%,HC:hydrocarbon),relatively low Rock-Eval Tmax values,and relatively high tricyclic terpane contents with a descending and mountain-shaped distribution.Furthermore,biomarker composition parameters indicate a higher thermal maturity than in-situ source rocks.Through a comparison of the extract biomarker fingerprints of adjacent reservoirs and mudstones in different boreholes,three types of influence patterns of migrated hydrocarbons are identified:the edge-influence of thin sandstone-thick mudstone,the mixed-influence of sandstone-mudstone interbedded,and the full-influence of thick sandstone-thin mudstone.This finding reminds us that the influence of migrated hydrocarbons must be considered when evaluating source rocks and conducting oil-source correlation. 展开更多
关键词 Organic geochemistry Source rock Influence of migrated hydrocarbons Fengcheng Formation Southern Mahu Sag
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The roles of macrophage migration inhibitory factor in retinal diseases 被引量:1
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作者 Hongbing Zhang Xianjiao Zhang +3 位作者 Hongsong Li Bing Wang Pei Chen Jiamin Meng 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期309-315,共7页
Macrophage migration inhibitory factor(MIF),a multifunctional cytokine,is secreted by various cells and participates in inflammatory reactions,including innate and adaptive immunity.There are some evidences that MIF i... Macrophage migration inhibitory factor(MIF),a multifunctional cytokine,is secreted by various cells and participates in inflammatory reactions,including innate and adaptive immunity.There are some evidences that MIF is involved in many vitreoretinal diseases.For example,MIF can exacerbate many types of uveitis;measurements of MIF levels can be used to monitor the effectiveness of uveitis treatment.MIF also alleviates trauma-induced and glaucoma-induced optic nerve damage.Furthermore,MIF is critical for retinal/choroidal neovascularization,especially complex neovascularization.MIF exacerbates retinal degeneration;thus,anti-MIF therapy may help to mitigate retinal degeneration.MIF protects uveal melanoma from attacks by natural killer cells.The mechanism underlying the effects of MIF in these diseases has been demonstrated:it binds to cluster of differentiation 74,inhibits the c-Jun N-terminal kinase pathway,and triggers mitogen-activated protein kinases,extracellular signal-regulated kinase-1/2,and the phosphoinositide-3-kinase/Akt pathway.MIF also upregulates Toll-like receptor 4 and activates the nuclear factor kappa-B signaling pathway.This review focuses on the structure and function of MIF and its receptors,including the effects of MIF on uveal inflammation,retinal degeneration,optic neuropathy,retinal/choroidal neovascularization,and uveal melanoma. 展开更多
关键词 diabetic retinopathy GLAUCOMA macrophage migration inhibitory factor migration inhibitory factor receptor optic neuropathy retinal degeneration retinal neovascular uveal melanoma UVEITIS
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Chemokine platelet factor 4 accelerates peripheral nerve regeneration by regulating Schwann cell activation and axon elongation 被引量:2
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作者 Miao Gu Xiao Cheng +3 位作者 Di Zhang Weiyan Wu Yi Cao Jianghong He 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期190-195,共6页
Schwann cells in peripheral nerves react to traumatic nerve injury by attempting to grow and regenerate.Howeve r,it is unclear what factors play a role in this process.In this study,we searched a GEO database and foun... Schwann cells in peripheral nerves react to traumatic nerve injury by attempting to grow and regenerate.Howeve r,it is unclear what factors play a role in this process.In this study,we searched a GEO database and found that expression of platelet factor 4 was markedly up-regulated after sciatic nerve injury.Platelet factor is an important molecule in cell apoptosis,diffe rentiation,survival,and proliferation.Further,polymerase chain reaction and immunohistochemical staining confirmed the change in platelet factor 4 in the sciatic nerve at different time points after injury.Enzyme-linked immunosorbent assay confirmed that platelet factor 4 was secreted by Schwann cells.We also found that silencing platelet factor 4 decreased the proliferation and migration of primary cultured Schwann cells,while exogenously applied platelet factor 4 stimulated Schwann cell prolife ration and migration and neuronal axon growth.Furthermore,knocking out platelet factor 4 inhibited the prolife ration of Schwann cells in injured rat sciatic nerve.These findings suggest that Schwann cell-secreted platelet factor 4 may facilitate peripheral nerve repair and regeneration by regulating Schwann cell activation and axon growth.Thus,platelet factor 4 may be a potential therapeutic target for traumatic peripheral nerve injury. 展开更多
关键词 axon elongation bioinformatic analysis cell migration cell proliferation dorsal root ganglia peripheral nerve regeneration peripheral nerve trauma platelet factor 4 rat sciatic nerve Schwann cells
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准确影像定位在颈部食管腔外异物取出术的应用
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作者 朱财明 陈伟章 +2 位作者 黎雄文 王晓锋 李嘉 《中国耳鼻咽喉头颈外科》 CSCD 2024年第9期604-606,共3页
目的分析颈部食管腔外异物的临床特点及准确影像定位在其诊断和治疗中的应用。方法回顾性分析2017年10月~2024年3月梅州市人民医院耳鼻咽喉科收治的10例颈部食管腔外异物患者,对颈胸部CT行多平面重建(multiplanar reconstruction,MPR),... 目的分析颈部食管腔外异物的临床特点及准确影像定位在其诊断和治疗中的应用。方法回顾性分析2017年10月~2024年3月梅州市人民医院耳鼻咽喉科收治的10例颈部食管腔外异物患者,对颈胸部CT行多平面重建(multiplanar reconstruction,MPR),从横断位、冠状位、矢状位判断异物位置,选择合适的手术入路。结果10例颈部食管腔外异物,2例金属和1例木质异物为外伤进入颈部,7例鱼骨为误吞鱼骨迁移颈部。术前影像定位提示异物在环状软骨和甲状软骨周3例,甲状腺内1例,相对应颈椎周2例,胸锁乳突肌周2例,舌骨周2例。支撑喉镜下取出2例,经颈部切开入路取出7例,1例未取出转上级医院治疗。术中彩超协助定位3例。所有患者随访至今均痊愈。结论准确影像定位可为颈部食管腔外异物选择合适手术入路提供依据,术中若异物寻找困难,可借助术中彩超精确定位异物,为成功取出异物提供有力保障。 展开更多
关键词 颈(Neck) 异物(Foreign Bodies) 体层摄影术 X线计算机(Tomography X-Ray Computed) 成像 三维(Imaging Three-Dimensional) 异物迁移(foreign bodies migration)
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Runx2 regulates peripheral nerve regeneration to promote Schwann cell migration and re-myelination 被引量:1
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作者 Rong Hu Xinpeng Dun +1 位作者 Lolita Singh Matthew C.Banton 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1575-1583,共9页
Runx2 is a major regulator of osteoblast differentiation and function;however,the role of Runx2 in peripheral nerve repair is unclea r.Here,we analyzed Runx2expression following injury and found that it was specifical... Runx2 is a major regulator of osteoblast differentiation and function;however,the role of Runx2 in peripheral nerve repair is unclea r.Here,we analyzed Runx2expression following injury and found that it was specifically up-regulated in Schwann cells.Furthermore,using Schwann cell-specific Runx2 knocko ut mice,we studied peripheral nerve development and regeneration and found that multiple steps in the regeneration process following sciatic nerve injury were Runx2-dependent.Changes observed in Runx2 knoc kout mice include increased prolife ration of Schwann cells,impaired Schwann cell migration and axonal regrowth,reduced re-myelination of axo ns,and a block in macrophage clearance in the late stage of regeneration.Taken together,our findings indicate that Runx2 is a key regulator of Schwann cell plasticity,and therefore peripheral nerve repair.Thus,our study shows that Runx2 plays a major role in Schwann cell migration,re-myelination,and peripheral nerve functional recovery following injury. 展开更多
关键词 macrophage clearance MIGRATION peripheral nerve injury regeneration re-myelination RUNX2 Schwann cells
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Borohydride Ammoniate Solid Electrolyte Design for All-Solid-State Mg Batteries 被引量:1
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作者 Yuepeng Pang Zhengfang Nie +5 位作者 Fen Xu Lixian Sun Junhe Yang Dalin Sun Fang Fang Shiyou Zheng 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期100-106,共7页
Searching for novel solid electrolytes is of great importance and challenge for all-solid-state Mg batteries.In this work,we develop an amorphous Mg borohydride ammoniate,Mg(BH_(4))_(2)·2NH_(3),as a solid Mg elec... Searching for novel solid electrolytes is of great importance and challenge for all-solid-state Mg batteries.In this work,we develop an amorphous Mg borohydride ammoniate,Mg(BH_(4))_(2)·2NH_(3),as a solid Mg electrolyte that prepared by a NH_(3)redistribution between 3D framework-γ-Mg(BH_(4))_(2)and Mg(BH_(4))_(2)·6NH_(3).Amorphous Mg(BH_(4))_(2)·2NH_(3)exhibits a high Mg-ion conductivity of 5×10^(-4)S cm^(-1)at 75℃,which is attributed to the fast migration of abundant Mg vacancies according to the theoretical calculations.Moreover,amorphous Mg(BH_(4))_(2)·2NH_(3)shows an apparent electrochemical stability window of 0-1.4 V with the help of in-situ formed interphases,which can prevent further side reactions without hindering the Mg-ion transfer.Based on the above superiorities,amorphous Mg(BH_(4))_(2)·2NH_(3)enables the stable cycling of all-solid-state Mg cells,as the critical current density reaches 3.2 mA cm^(-2)for Mg symmetrical cells and the reversible specific capacity reaches 141 mAh g^(-1)with a coulombic efficiency of 91.7%(first cycle)for Mg||TiS_(2)cells. 展开更多
关键词 all-solid-state Mg batteries amorphization Mg borohydride ammoniate Mg vacancy migration solid electrolyte
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Migration pattern of a population of Barn Swallows(Hirundo rustica)breeding in East Asian tropical region
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作者 Li Tian Yu Liu +3 位作者 Yang Wu Zimei Feng Dan Hu Zhengwang Zhang 《Avian Research》 SCIE CSCD 2024年第3期299-307,共9页
Birds exhibit a high degree of migratory diversity,which is influenced by various ecological factors and life history strategies.Conducting studies on tropical bird migration,of which research is scarce,and comparing ... Birds exhibit a high degree of migratory diversity,which is influenced by various ecological factors and life history strategies.Conducting studies on tropical bird migration,of which research is scarce,and comparing it with temperate birds can enhance our understanding of bird migration behaviour and its underlying mecha-nisms.In this study,we explored the migration behaviour of a breeding population of the Barn Swallow(Hirundo rustica)in Zhanjiang,southern China,a region located in the northern tropics,using light-level geolocators.From 2021 to 2023,we deployed geolocators on 92 breeding swallows and retrieved geolocators successfully from 23 individuals.These swallows all exhibited migratory behaviour,and wintering on various islands in Southeast Asia.They displayed sex differences in their wintering locations.All males concentrated in Borneo,while females primarily chose Borneo but also dispersed to the Philippines,South China Sea,and Vietnam for wintering.The studied swallow population adopted a seasonal migration pattern of“indirect in autumn,direct in spring”,bypassing the ecological barrier of the South China Sea in autumn and tending to directly cross it in spring migration.Moreover,the distance and duration of autumn migration was significantly longer than those of the spring migration.Compared to temperate Barn Swallows,the Barn Swallow population breeding in Zhanjiang adopts a pattern of“intra-tropical migration”and initiates autumn migration earlier.The formation of their migration pattern may be limited by ecological and physiological factors. 展开更多
关键词 ASIA Chain migration Light-level geolocators MIGRATION Northern tropics
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Individual consistency in spatiotemporal characteristics of migratory Whimbrels in the East Asian-Australasian Flyway
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作者 Siwei An Fenliang Kuang +9 位作者 Wei Wu Chris J.Hassell Jonathan T.Coleman Zijing Gao Xuena Sun Yue Yuan Grace Maglio Kar-Sin K.Leung Xuesong Feng Zhijun Ma 《Avian Research》 SCIE CSCD 2024年第3期308-315,共8页
Many migratory birds exhibit interannual consistency in migration schedules,routes and stopover sites.Detecting the interannual consistency in spatiotemporal characteristics helps understand the maintenance of migrati... Many migratory birds exhibit interannual consistency in migration schedules,routes and stopover sites.Detecting the interannual consistency in spatiotemporal characteristics helps understand the maintenance of migration and enables the implementation of targeted conservation measures.We tracked the migration of Whimbrel(Numenius phaeopus)in the East Asian-Australasian Flyway and collected spatiotemporal data from individuals that were tracked for at least two years.Wilcoxon non-parametric tests were used to compare the interannual variations in the dates of departure from and arrival at breeding/nonbreeding sites,and the inter-annual variation in the longitudes when the same individual across the same latitudes.Whimbrels exhibited a high degree of consistency in the use of breeding,nonbreeding,and stopover sites between years.The variation of arrival dates at nonbreeding sites was significantly larger than that of the departure dates from nonbreeding and breeding sites.Repeatedly used stopover sites by the same individuals in multiple years were concentrated in the Yellow Sea coast during northward migration,but were more widespread during southward migration.The stopover duration at repeatedly used sites was significantly longer than that at sites used only once.When flying across the Yellow Sea,Whimbrels breeding in Sakha(Yakutia)exhibited the highest consistency in migration routes in both autumn and spring.Moreover,the consistency in migration routes of Yakutia breeding birds was generally higher than that of birds breeding in Chukotka.Our results suggest that the northward migration schedule of the Whimbrels is mainly controlled by endogenous factors,while the southward migration schedule is less affected by endogenous factors.The repeated use of stopover sites in the Yellow Sea coast suggests this region is important for the migration of Whimbrel,and thus has high conservation value. 展开更多
关键词 CONSISTENCY Migration route Migration timing SHOREBIRD
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Defect mediated losses and degradation of perovskite solar cells:Origin impacts and reliable characterization techniques
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作者 Himangshu Baishy Ramkrishna Das Adhikari +5 位作者 Mayur Jagdishbhai Patel Deepak Yadav Tapashi Sarmah Mizanur Alam Manab Kalita Parameswar Krishnan lyer 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期217-253,共37页
The rapid advancement of halide-based hybrid perovskite materials has garnered significant research attention,particularly in the domain of photovoltaic technology.Owing to their exceptional optoelec-tronic properties... The rapid advancement of halide-based hybrid perovskite materials has garnered significant research attention,particularly in the domain of photovoltaic technology.Owing to their exceptional optoelec-tronic properties,they demonstrated power conversion efficiency(PcE)of over 25%in single junction solar cells.Despite the notable progress in PCE over the past decade,the inherent high defect density pre-senting in perovskite materials gives rise to several loss mechanisms and associated ion migration in per-ovskite solar cells(PsCs)during operational conditions.These factors collectively contribute to a significant stability challenge in PsCs,placing their longevity far behind for commercialization.While numerous reports have explored defects,ion migration,and their impacts on device performance,a com-prehensive correlation between the types of defects and the degradation kinetics of perovskite materials and PsCs has been lacking.In this context,this review aims to provide a comprehensive overview of the origins of defects and ion migration,emphasizing their correlation with the degradation kinetics of per-ovskite materials and PsCs,leveraging reliable characterization techniques.Furthermore,these charac-terization techniques are intended to comprehend loss mechanisms by different passivation approaches to enhance the durability and PCE of PSCs. 展开更多
关键词 Perovskite solar cells Defects lon migration DEGRADATION Stability
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Effect of thermal maturation and organic matter content on oil shale fracturing
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作者 Fatemeh Saberi Mahboubeh Hosseini‑Barzi 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期16-34,共19页
The Pabdeh Formation represents organic matter enrichment in some oil fields,which can be considered a source rock.This study is based on the Rock–Eval,Iatroscan,and electron microscopy imaging results before and aft... The Pabdeh Formation represents organic matter enrichment in some oil fields,which can be considered a source rock.This study is based on the Rock–Eval,Iatroscan,and electron microscopy imaging results before and after heating the samples.We discovered this immature shale that undergoes burial and diagenesis,in which organic matter is converted into hydro-carbons.Primary migration is the process that transports hydrocarbons in the source rock.We investigated this phenomenon by developing a model that simulates hydrocarbon generation and fluid pressure during kerogen-to-hydrocarbon conversion.Microfractures initially formed at the tip/edge of kerogen and were filled with hydrocarbons,but as catagenesis progressed,the pressure caused by the volume increase of kerogen decreased due to hydrocarbon release.The transformation of solid kerogen into low-density bitumen/oil increased the pressure,leading to the development of damage zones in the source rock.The Pabdeh Formation’s small porethroats hindered effective expulsion,causing an increase in pore fluid pressure inside the initial microfractures.The stress accumulated due to hydrocarbon production,reaching the rock’s fracture strength,further contributed to damage zone development.During the expansion process,microfractures preferentially grew in low-strength pathways such as lithology changes,laminae boundaries,and pre-existing microfractures.When the porous pressure created by each kerogen overlapped,individual microfractures interconnected,forming a network of microfractures within the source rock.This research sheds light on the complex interplay between temperature,hydrocarbon generation,and the development of expulsion fractures in the Pabdeh Formation,providing valuable insights for understanding and optimizing hydrocarbon extraction in similar geological settings. 展开更多
关键词 Oil shale MICROFRACTURE Hydrocarbon generation Organic matter Thermal maturation Primary migration
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Migratory mode transition of astrocyte progenitors in the cerebral cortex: an intrinsic or extrinsic cell process?
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作者 Michio Miyajima Hidenori Tabata Kazunori Nakajima 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期471-472,共2页
The cerebral cortex is comprised of properly localized cell types that exert their specific functions.In the developing brain,cells migrate from the germinal region to their functional locations(Silva et al.,2019;Coss... The cerebral cortex is comprised of properly localized cell types that exert their specific functions.In the developing brain,cells migrate from the germinal region to their functional locations(Silva et al.,2019;Cossart and Garel,2022).For example,neocortical excitatory neurons are generated in the cerebral ventricular and subventricular zones,move to the developing cortical plate via radial migration,and reside in a radial array of six neuronal layers(Oishi and Nakajima,2018).On the other hand,cortical interneurons are mainly generated in ganglionic eminences,migrate tangentially across the cerebral cortex,and reach their final destinations in the cortex(Lim et al.,2018).The failure of neuronal migration leads to defects in cortical layer formation.While the mechanisms of neuronal distribution have been well examined,how astrocytes are diffusely distributed in the cortex is still unclear.Astrocytes are glial cells in the cerebral cortex with several functions,including metabolic support and synapse formation(Abbott et al.,2006;Bosworth and Allen,2017;Allen and Lyons,2018).For example,astrocytes establish synaptic connectivity in the developing brain while they contact numerous synapses and maintain optimal neuronal activity in the adult brain.In the developing brain,astrocytes are primarily generated from radial glia after the neurogenic period.While a certain type of astrocyte called fibrous astrocytes populates the white matter,protoplasmic astrocytes migrate to the cortical plate during neural network formation. 展开更多
关键词 CEREBRAL MIGRATE ABBOTT
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Mineralogical study and significance of the basalt-hosted Carlin-type Au deposits in southwestern Guizhou Province,China
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作者 Yuhong Yang Shen Liu +3 位作者 Jianzhong Liu Zepeng Wang Bingqiang Zhang Chengfu Yang 《Acta Geochimica》 EI CAS CSCD 2024年第6期1241-1254,共14页
The Jiadi and Damaidi gold deposits in southwest Guizhou Province are the largest basalt-hosted Carlintype gold deposits recently discovered in China.This study uses the Tescan Integrated Mineral Analyzer,supported by... The Jiadi and Damaidi gold deposits in southwest Guizhou Province are the largest basalt-hosted Carlintype gold deposits recently discovered in China.This study uses the Tescan Integrated Mineral Analyzer,supported by detailed field investigations,regional geological data,and extensive sample collections,including mineralized ore,altered wall rock,and unaltered basalt samples,for orebearing and geochemical analyses.Comparative analysis between altered and unaltered basalt samples revealed a mineral assemblage of sericite,quartz,and pyrite.This mineral composition forms through the hydrothermal alteration of unaltered basalt,originally containing feldspar,pyroxene,and ilmenite.The wall rock primarily features sericite,quartz,and hematite.During the alteration process,major,trace,and rare earth elements notably migrate.In the Jiadi deposit,K_(2)O,Rb,Au,and REE significantly increase,while Na_(2)O,CaO,MgO,and MnO decrease.SiO_(2),Al_(2)O_(3),and Fe_(2)O_(3)levels remain relatively stable.In the Damaidi deposit,K_(2)O,Rb,and Au enrich,contrasting with the depletion of Na_(2)O,CaO,MgO,and MnO,while SiO_(2),Fe_(2)O_(3),Al_(2)O_(3),TiO_(2),and REE show no significant changes.In the wall rock,TiO_(2),Al_(2)O_(3),K_(2)O,and REE increase,while Na_(2)O,CaO,MgO,and MnO decrease;SiO_(2)and Fe_(2)O_(3)content remains unchanged.The mineralization process likely originated from mid-to low-temperature,reductive magmatic hydrothermal fluids rich in CO_(2),CH_(4),N_(2),H^(+),S^(2-),HS^(-),H_(3)AsO_(3),and[Au(HS_(2)]^(-).These fluids migrated to tectonically weak zones in the Lianhuashan area,where Emeishan basalts are present.They reacted with Fe-bearing minerals in the basalt,such as ferro-hornblende and ilmenite,forming pyrite,arsenic-bearing pyrite,and arsenopyrite,thus enriching Au in these minerals.Additionally,K^(+)and H^(+)in the fluid reacted with plagioclase in the basalt,forming sericite and quartz.As the fluid entered the wall rock from structural weak zones,its oxidation increased,leading to the complete or partial reaction of Fe-bearing minerals in the wall rock,resulting in the formation of hematite or magnetite.This mineralization process is similar to that observed in carbonate-hosted Carlin-type gold deposits in southwest Guizhou,with the primary distinction being the iron source.In carbonate deposits,iron originates from ferridolomite within the wall rock,while in basalt-hosted deposits,it derives from ferripyroxene and ilmenite. 展开更多
关键词 BASALTIC Ore-bearing rocks CARLIN-TYPE Au deposit Mineralogy Mineral assemblage Element migration
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Methanolic extract of Ephedra alata inhibits breast cancer cells in vitro and in vivo
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作者 Fairouz Sioud Aida Lahmer +2 位作者 Mouna Selmi Fadwa Chaabane Leila Chekir-Ghedira 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第4期154-161,共8页
Objective:To determine the anticancer potential of the methanolic extract from Ephedra alata against breast cancer both in vitro and in vivo.Methods:The effects of the methanolic extract of Ephedra alata on the viabil... Objective:To determine the anticancer potential of the methanolic extract from Ephedra alata against breast cancer both in vitro and in vivo.Methods:The effects of the methanolic extract of Ephedra alata on the viability,migration as well as apoptosis of breast cancer 4T1 cells were measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay,Transwell assay,and annexin V-FITC staining assay,respectively.Histological examination was also carried out.Moreover,a murine breast cancer model was established to evaluate the inhibitory effect of the extract.Biochemical parameters including hepatic and non-hepatic enzymes,malondialdehyde,and glutathione were investigated.Results:The methanolic extract of Ephedra alata showed a strong anti-proliferative and anti-migratory activity against 4T1 cells in a dose-dependent manner.It also induced apoptosis in 4T1 cells.In an in vivo mouse model,the extract markedly inhibited tumor growth,reduced malondialdehyde,and hepatic and non-hepatic enzymes as well as increased glutathione level.Conclusions:The methanolic extract of Ephedra alata inhibits breast cancer in vitro and in vivo,which may be a promising anticancer agent. 展开更多
关键词 EPHEDRA Breast cancer Apoptosis ANTIOXIDANT MIGRATION
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Phase-stable wide-bandgap perovskites enabled by suppressed ion migration
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作者 Zhiyu Gao Yu Zhu +20 位作者 Jingwei Zhu Cong Chen Zongjin Yi Yi Luo Yuliang Xu Kai Wu Tianshu Ma Fangfang Cao Zijun Chen Fang Yao Juncheng Wang Wenwu Wang Chuanxiao Xiao Hao Huang Hongxiang Li Qianqian Lin Pei Cheng Changlei Wang Xia Hao Guanggen Zeng Dewei Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期120-128,共9页
Wide-bandgap(>1.7 eV)perovskites suffer from severe light-induced phase segregation due to high bromine content,causing irreversible damage to devices stability.However,the strategies of suppressing photoinduced ph... Wide-bandgap(>1.7 eV)perovskites suffer from severe light-induced phase segregation due to high bromine content,causing irreversible damage to devices stability.However,the strategies of suppressing photoinduced phase segregation and related mechanisms have not been fully disclosed.Here,we report a new passivation agent 4-aminotetrahydrothiopyran hydrochloride(4-ATpHCl)with multifunctional groups for the interface treatment of a 1.77-eV wide-bandgap perovskite film.4-ATpH^(+)impeded halogen ion migration by anchoring on the perovskite surface,leading to the inhibition of phase segregation and thus the passivation of defects,which is ascribed to the interaction of 4-ATpH^(+)with perovskite and the formation of low-dimensional perovskites.Finally,the champion device achieved an efficiency of 19.32%with an open-circuit voltage(V_(OC))of 1.314 V and a fill factor of 83.32%.Moreover,4-ATpHCl modified device exhibited significant improved stability as compared with control one.The target device maintained 80%of its initial efficiency after 519 h of maximum power output(MPP)tracking under 1 sun illumination,however,the control device showed a rapid decrease in efficiency after 267 h.Finally,an efficiency of 27.38%of the champion 4-terminal all-perovskite tandem solar cell was achieved by mechanically stacking this wide-bandgap top subcell with a 1.25-eV low-bandgap perovskite bottom subcell. 展开更多
关键词 Wide-bandgap perovskite Phase segregation lon migration Interface post-treatment All-perovskite tandems
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Quantifying the Effects of Near-Surface Viscosity on Seismic Acquisition Geometry: A case study from Chepaizi Exploration Area, Junggar Basin (NW China)
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作者 Hongqin Ren Tao Liu +2 位作者 Xu Zhang Jian Zhang Renwei Ding 《Applied Geophysics》 SCIE CSCD 2024年第3期433-439,616,共8页
The Chepaizi Exploration Area,Junggar Basin(NW China)holds substantial importance for seismic exploration endeavors,yet it poses notable challenges due to the intricate nature of its subsurface and near-surface condit... The Chepaizi Exploration Area,Junggar Basin(NW China)holds substantial importance for seismic exploration endeavors,yet it poses notable challenges due to the intricate nature of its subsurface and near-surface conditions.To address these challenges,we introduce a novel and comprehensive workflow tailored to evaluate and optimize seismic acquisition geometries while considering the impacts of near-surface viscosity.By integrating geological knowledge,historical seismic data,and subsurface modeling,we conduct simulations employing the visco-acoustic wave equation and reverse-time migration to produce detailed subsurface images.The quality of these images is quantitatively evaluated using a local similarity metric,a pivotal tool for evaluating the accuracy of seismic imaging.The culmination of this workflow results in an automated optimization strategy for acquisition geometries that enhances subsurface exploration.Our proposed methodology underscores the importance of incorporating near-surface viscosity effects in seismic imaging,offering a robust framework for improving the accuracy of subsurface imaging.Herein,we aim to contribute to the advancement of seismic imaging methodologies by providing valuable insights for achieving high-quality seismic exploration outcomes in regions characterized by complex subsurface and near-surface conditions. 展开更多
关键词 seismic acquisition visco-acoustic reverse-time migration local similarity
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Single-cell manipulation by two-dimensional micropatterning
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作者 Xuehe Ma Haimei Zhang +7 位作者 Shiyu Deng Qiushuo Sun Qingsong Hu Yuhang Pan Fen Hu Imshik Lee Fulin Xing Leiting Pan 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期45-59,共15页
Cells are highly sensitive to their geometrical and mechanical microenvironment that directly regulate cell shape,cytoskeleton and organelle,as well as the nucleus morphology and genetic expression.The emerging two-di... Cells are highly sensitive to their geometrical and mechanical microenvironment that directly regulate cell shape,cytoskeleton and organelle,as well as the nucleus morphology and genetic expression.The emerging two-dimensional micropatterning techniques offer powerful tools to construct controllable and well-organized microenvironment for single-cell level investigations with qualitative analysis,cellular standardization,and in vivo environment mimicking.Here,we provide an overview of the basic principle and characteristics of the two most widely-used micropatterning techniques,including photolithographic micropatterning and soft lithography micropatterning.Moreover,we summarize the application of micropatterning technique in controlling cytoskeleton,cell migration,nucleus and gene expression,as well as intercellular communication. 展开更多
关键词 Two-dimensional micropatterning CYTOSKELETON cell migration extracellular matrix intercellular communication gene expression
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