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Effects of Chlorine and Chlorine Monoxide on Stratospheric Ozone Depletion
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作者 Laurie Wei Ibraheem Alelmi Sen Nieh 《Atmospheric and Climate Sciences》 2024年第1期136-153,共18页
This paper presents a system approach of mass balance calculations of ozone and other species under diffusion-convection-reaction processes to study the impacts of major ozone-depleting chemicals, chlorine (Cl) and ch... This paper presents a system approach of mass balance calculations of ozone and other species under diffusion-convection-reaction processes to study the impacts of major ozone-depleting chemicals, chlorine (Cl) and chlorine monoxide (ClO), and the effect of photolysis on ozone concentrations, ozone depletion, total ozone abundance, and ozone layer along the altitude in the stratosphere. The calculated ozone concentrations and profile of the layer followed a similar trend and were generally in good agreement with the measurements above the tropical area. The calculated peak of the layer was at the same mid-stratosphere at Z = 30 km with a peak concentration and total ozone abundance about 20% higher than the measured peak concentration of 8.0 ppm and total abundance of 399 DU. In the presence of Cl and ClO, the calculated ozone concentrations and total abundance were substantially reduced. Cl generally depleted more uniformly of ozone across the altitude, while ClO reduced substantially the ozone in the upper stratosphere and thus shifted the peak of the layer to a much lower elevation at Z = 14 km. Although both ClO and Cl are active ozone-depleting chemicals, ClO was found to have a more pronounced impact on ozone depletion and distribution than Cl. The possible explanations of these interesting phenomena were discussed and elaborated. The approach and calculations in this paper were shown to be useful in providing an initial insight into the structure and behavior of the complex ozone layer. 展开更多
关键词 OZONE Ozone depletion CHLORINE Chlorine Monoxide PHOTOLYSIS Dobson Unit
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Development of multi-group Monte-Carlo transport and depletion coupling calculation method and verification with metal-fueled fast reactor 被引量:2
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作者 Hui Guo Yi‑Wei Wu +2 位作者 Qu‑Fei Song Yu‑Yang Shen Han‑Yang Gu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第11期20-39,共20页
The accurate modeling of depletion,intricately tied to the solution of the neutron transport equation,is crucial for the design,analysis,and licensing of nuclear reactors and their fuel cycles.This paper introduces a ... The accurate modeling of depletion,intricately tied to the solution of the neutron transport equation,is crucial for the design,analysis,and licensing of nuclear reactors and their fuel cycles.This paper introduces a novel multi-group Monte-Carlo depletion calculation approach.Multi-group cross-sections(MGXS)are derived from both 3D whole-core model and 2D fuel subassembly model using the continuous-energy Monte-Carlo method.Core calculations employ the multi-group Monte-Carlo method,accommodating both homogeneous and specific local heterogeneous geometries.The proposed method has been validated against the MET-1000 metal-fueled fast reactors,using both the OECD/NEA benchmark and a new refueling benchmark introduced in this paper.Our findings suggest that microscopic MGXS,produced via the Monte-Carlo method,are viable for fast reactor depletion analyses.Furthermore,the locally heterogeneous model with angular-dependent MGXS offers robust predictions for core reactivity,control rod value,sodium void value,Doppler constants,power distribution,and concentration levels. 展开更多
关键词 Monte-Carlo Multi-group cross-section generation depletion Fast reactors Metallic fuel
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Impacts of species depletion on the food web structure of a marine ecosystem based on topological network analysis
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作者 Congjun Xu Jun Xu +2 位作者 Fan Li Yiping Ren Ying Xue 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第11期136-145,共10页
Single-species management ignores the interactions between species,and ecosystem-based fisheries management(EBFM)has become a main method to fisheries management.Understanding food web structures and species interacti... Single-species management ignores the interactions between species,and ecosystem-based fisheries management(EBFM)has become a main method to fisheries management.Understanding food web structures and species interactions is essential for the implementation of EBFM and maintenance of ecosystem functions.Overfishing is one of the main reasons behind the depletion,which could even lead to the depletion of some target species in local areas.So understanding the impacts of species depletion on food web structures is important for the implementation of EBFM.The impacts of species depletion can be transmitted through the food web and cause the local extinction of both target and non-target species.In this study,topological network analysis was applied to examine the impacts of species depletion on the food web structure of Haizhou Bay.Results showed that fine crayfish Leptochela gracilis,squid Loligo sp.,and Japanese snapping shrimp Alpheus japonicus have the highest numbers of outgoing links(48,32 and 31 respectively);thus,these species may be considered key prey species.Whitespotted conger Conger myriaster,fat greenling Hexagrammos otakii,and bluefin gurnard Chelidonichthys kumu were key predators with the highest number of incoming links(37,36 and 35 respectively).The competition graphs derived from the Haizhou Bay food web were highly connected(more than 40%predators sharing over 10 common prey species),and showed close trophic interaction between high trophic level fishes.Simulation analysis showed that the food web structure has small changes to the depletion of species in a highly complex food web.The most-connected target species did not necessarily indicate high structural importance;however,some species with low connectivity may demonstrate stronger trophic interactions and play important ecological roles in the food web.But most species were more sensitive to the depletion of the most-connected target species than other target species(for instance,for zooplankton,closeness centrality 13.876 in D6,but closeness centrality 82.143 in original food web).Therefore,EBFM should focus on the most-connected target species,but also on those species with few but strong links and feeding relationships in the food web. 展开更多
关键词 Haizhou Bay most-connected target species food web structure depletion fishery management feeding strategy
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Trim21 depletion alleviates bone loss in osteoporosis via activation of YAP1/β-catenin signaling
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作者 Ri-Xu Liu Rong-He Gu +15 位作者 Zhi-Peng Li Zhi-Quan Hao Qin-Xiao Hu Zhen-Yan Li Xiao-Gang Wang Wang Tang Xiao-He Wang Yu-Kai Zeng Zhen-Wei Li Qiu Dong Xiao-Feng Zhu Di Chen Ke-Wei Zhao Rong-Hua Zhang Zhen-Gang Zha Huan-Tian Zhang 《Bone Research》 SCIE CAS CSCD 2023年第4期819-833,共15页
Despite the diverse roles of tripartite motif(Trim)-containing proteins in the regulation of autophagy,the innate immune response,and cell differentiation,their roles in skeletal diseases are largely unknown.We recent... Despite the diverse roles of tripartite motif(Trim)-containing proteins in the regulation of autophagy,the innate immune response,and cell differentiation,their roles in skeletal diseases are largely unknown.We recently demonstrated that Trim21 plays a crucial role in regulating osteoblast(OB)differentiation in osteosarcoma.However,how Trim21 contributes to skeletal degenerative disorders,including osteoporosis,remains unknown.First,human and mouse bone specimens were evaluated,and the results showed that Trim21 expression was significantly elevated in bone tissues obtained from osteoporosis patients.Next,we found that global knockout of the Trim21 gene(KO,Trim2^(1-/-))resulted in higher bone mass compared to that of the control littermates.We further demonstrated that loss of Trim21 promoted bone formation by enhancing the osteogenic differentiation of bone marrow mesenchymal stem cells(BMSCs)and elevating the activity of OBs;moreover,Trim21 depletion suppressed osteoclast(OC)formation of RAW264.7 cells.In addition,the differentiation of OCs from bone marrow-derived macrophages(BMMs)isolated from Trim21^(-/-)and Ctsk-cre;Trim21^(f/f)mice was largely compromised compared to that of the littermate control mice.Mechanistically,YAP1/β-catenin signaling was identified and demonstrated to be required for the Trim21-mediated osteogenic differentiation of BMSCs.More importantly,the loss of Trim21 prevented ovariectomy(OVX)-and lipopolysaccharide(LPS)-induced bone loss in vivo by orchestrating the coupling of OBs and OCs through YAP1 signaling.Our current study demonstrated that Trim21 is crucial for regulating OB-mediated bone formation and OC-mediated bone resorption,thereby providing a basis for exploring Trim21 as a novel dual-targeting approach for treating osteoporosis and pathological bone loss. 展开更多
关键词 YAP1 OSTEOPOROSIS depletion
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A randomized trial of iron depletion in patients with nonalcoholic fatty liver disease and hyperferritinemia 被引量:8
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作者 Luca Valenti Anna Ludovica Fracanzani +6 位作者 Paola Dongiovanni Serena Rovida Raffaela Rametta Erika Fatta Edoardo Alessandro Pulixi Marco Maggioni Silvia Fargion 《World Journal of Gastroenterology》 SCIE CAS 2014年第11期3002-3010,共9页
AIM:To compare iron depletion to lifestyle changes alone in patients with severe nonalcoholic fatty liver disease(NAFLD)and hyperferritinemia,a frequent feature associated with more severe liver damage,despite at leas... AIM:To compare iron depletion to lifestyle changes alone in patients with severe nonalcoholic fatty liver disease(NAFLD)and hyperferritinemia,a frequent feature associated with more severe liver damage,despite at least 6 mo of lifestyle changes.METHODS:Eligible subjects had to be 18-75 years old who underwent liver biopsy for ultrasonographically detected liver steatosis and hyperferritinemia,ferritin levels≥250 ng/mL,and NAFLD activity score>1.Iron depletion had to be achieved by removing 350 cc of blood every 10-15 d according to baseline hemoglobin values and venesection tolerance,until ferritin<30 ng/mL and/or transferrin saturation(TS)<25%.Thirty-eight patients were randomized 1:1 to phlebotomy(n=21)or lifestyle changes alone(n=17).The main outcome of the study was improvement in liver damage according to the NAFLD activity score at 2 years,secondary outcomes were improvements in liver enzymes[alanine aminotransferases(ALT),aspartate aminotransferase(AST),and gamma-glutamyl-transferases(GGT)].RESULTS:Phlebotomy was associated with normalization of iron parameters without adverse events.In the21 patients compliant to the study protocol,the rate of histological improvement was higher in iron depleted vs control subjects(8/12,67%vs 2/9,22%,P=0.039).There was a better improvement in steatosis grade in iron depleted vs control patients(P=0.02).In patients followed-up at two years(n=35),ALT,AST,and GGT levels were lower in iron-depleted than in control patients(P<0.05).The prevalence of subjects with improvement in histological damage or,in the absence of liver biopsy,ALT decrease≥20%(associated with histological improvement in biopsied patients)was higher in the phlebotomy than in the control arm(P=0.022).The effect of iron depletion on liver damage improvement as assessed by histology or ALT decrease≥20%was independent of baseline AST/ALT ratio and insulin resistance(P=0.0001).CONCLUSION:Iron depletion by phlebotomy is likely associated with a higher rate of improvement of histological liver damage than lifestyle changes alone in patients with NAFLD and hyperferritinemia,and with amelioration of liver enzymes. 展开更多
关键词 NONALCOHOLIC FATTY LIVER disease IRON depletion RA
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A Simulation Study of Ionization Depletion in the Auroral Ionospheric F-Region Caused by Strong Convection Electric Field 被引量:4
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作者 Cai Hong-tao Ma Shu-ying G. Kirchengast 《Wuhan University Journal of Natural Sciences》 EI CAS 2001年第3期680-686,共7页
The effects of strong convection electric field on the electron density in the auroral ionospheric F region have been simulated numerically by means of a physical model. It is found that an enhancement of electric fie... The effects of strong convection electric field on the electron density in the auroral ionospheric F region have been simulated numerically by means of a physical model. It is found that an enhancement of electric field directed west northward in post noon or west southward in pre noon results in an ionization depletion with its maximum at altitudes 40 50 km higher than that of the F 2 peak. When the enhanced electric field lasts for 45 min and has a maximum about 32 mV/m, the resulted ionization depletions reach their maximum at the time just ~10 min behind the time when the convection electric field and ion temperature enhancements reach their maximum. This is consistent well with EISCAT observations. The magnitudes of the percentage ionization depletions and their recovery time are dependent not only on the intensity of the electric field, but also on the diurnal variation phase of the background electron density. 展开更多
关键词 auroral IONOSPHERE IONOSPHERIC model numerical simulation CONVECTION electric field IONIZATION depletion
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Numerical investigation on the effect of depletion-induced stress reorientation on infill well hydraulic fracture propagation 被引量:4
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作者 Feng-Shou Zhang Liu-Ke Huang +5 位作者 Lin Yang Egor Dontsov Ding-Wei Weng Hong-Bo Liang Zi-Rui Yin Ji-Zhou Tang 《Petroleum Science》 SCIE CAS CSCD 2022年第1期296-308,共13页
Depletion-induced stress change causes the redistribution of stress field in reservoirs,which can lead to the reorientation of principal stresses.Stress reorientation has a direct impact on fracture propagation of inf... Depletion-induced stress change causes the redistribution of stress field in reservoirs,which can lead to the reorientation of principal stresses.Stress reorientation has a direct impact on fracture propagation of infill wells.To understand the effect of stress reorientation on the propagation of infill well’s fractures,an integrated simulation workflow that combines the reservoir flow calculation and the infill well hydraulic fracturing modeling is adopted.The reservoir simulation is computed to examine the relationship between the extent of stress reversal region and reservoir properties.Then,the hydraulic fracturing model considering the altered stress field for production is built to characterize the stress evolution of secondary fracturing.Numerical simulations show that stress reorientation may occur due to the decreasing of the horizontal stresses in an elliptical region around the parent well.Also,the initial stress difference is the driving factor for stress reorientation.However,the bottom hole pressure,permeability and other properties connected with fluid flow control timing of the stress reorientation.The decrease of the horizontal stresses around the parent well lead to asymmetrical propagation of a hydraulic fracture of the infill well.The study provides insights on understanding the influence of stress reorientation to the infill well fracturing treatment and interference between parent and infill wells. 展开更多
关键词 Infill well depletion Hydraulic fracture Stress reorientation Asymmetry fracture
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Plant-to-plant direct competition for belowground resource in an overlapping depletion zone 被引量:4
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作者 Amit CHAKRABORTY 《Journal of Arid Land》 SCIE 2009年第1期9-15,共7页
In response to limited availability of soil resources in basal root zone, plant extends its roots into nearby resource-rich zones to fulfill essential resource demands for survival and reproduction. This root prolifer... In response to limited availability of soil resources in basal root zone, plant extends its roots into nearby resource-rich zones to fulfill essential resource demands for survival and reproduction. This root proliferation into that enriched zones occupied by other plants constitutes interplant overlapping rooting zones and thereby the overlapping depletion zones, causing reduction in resource uptake by neighboring plants. By incorporating this mechanism into the classic resource competition model, we study interplant direct competition through their rooting system in an overlapping depletion zone. The model results indicate an extension of Tilman's R* rule that has already been proved true when plants compete indirectly through their effect on shared resources. The results reveal that plant's direct competitive ability (i.e., the ability to occupy an overlapping depletion zone by excluding others) can be characterized by its R*-value, where a best competitor having lowest R*-value excludes others from an overlapping zone and occupies the zone by depleting the resource level to the lowest as in its non-overlapping depletion zone. By analyzing the model, we find a suite of traits that confers R* variation among directly competing plants. This suite of traits would be a useful proxy measure for R* that do not necessarily require to establish equilibrium field monoculture-a requirement for R* measurement in the field. 展开更多
关键词 RESOURCE capture efficiency NICHE differentiation root proliferation RESOURCE depletion ZONE
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DEPLETION POTENTIAL OF COLLOIDS: A DIRECT SIMULATION STUDY 被引量:4
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作者 李卫华 薛松 马红孺 《Journal of Shanghai Jiaotong university(Science)》 EI 2001年第2期126-130,共5页
The depletion interaction between a big sphere and a hard wall and between two big hard spheres in a hard sphere colloidal sytem was studied by the Monte Carlo method. Direct simulation of free energy difference was p... The depletion interaction between a big sphere and a hard wall and between two big hard spheres in a hard sphere colloidal sytem was studied by the Monte Carlo method. Direct simulation of free energy difference was performed by means of the Acceptance Ratio Method (ARM). 展开更多
关键词 depletion force COLLOID SIMULATION
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Characteristic response of striatal astrocytes to dopamine depletion 被引量:2
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作者 Yao-Feng Zhu Wei-Ping Wang +5 位作者 Xue-Feng Zheng Zhi Chen Tao Chen Zi-Yun Huang Lin-Ju Jia Wan-Long Lei 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第4期724-730,共7页
Astrocytes and astrocyte-related proteins play important roles in maintaining normal brain function,and also regulate pathological processes in brain diseases and injury.However,the role of astrocytes in the dopamine-... Astrocytes and astrocyte-related proteins play important roles in maintaining normal brain function,and also regulate pathological processes in brain diseases and injury.However,the role of astrocytes in the dopamine-depleted striatum remains unclear.A rat model of Parkinson’s disease was therefore established by injecting 10μL 6-hydroxydopamine(2.5μg/μL)into the right medial forebrain bundle.Immunohistochemical staining was used to detect the immunoreactivity of glial fibrillary acidic protein(GFAP),calcium-binding protein B(S100B),and signal transducer and activator of transcription 3(STAT3)in the striatum,and to investigate the co-expression of GFAP with S100B and STAT3.Western blot assay was used to measure the protein expression of GFAP,S100B,and STAT3 in the striatum.Results demonstrated that striatal GFAP-immunoreactive cells had an astrocytic appearance under normal conditions,but that dopamine depletion induced a reactive phenotype with obvious morphological changes.The normal striatum also contained S100B and STAT3 expression.S100B-immunoreactive cells were uniform in the striatum,with round bodies and sparse,thin processes.STAT3-immunoreactive cells presented round cell bodies with sparse processes,or were darkly stained with a large cell body.Dopamine deprivation induced by 6-hydroxydopamine significantly enhanced the immunohistochemical positive reaction of S100B and STAT3.Normal striatal astrocytes expressed both S100B and STAT3.Striatal dopamine deprivation increased the number of GFAP/S100B and GFAP/STAT3 double-labeled cells,and increased the protein levels of GFAP,S100B,and STAT3.The present results suggest that morphological changes in astrocytes and changes in expression levels of astrocyte-related proteins are involved in the pathological process of striatal dopamine depletion.The study was approved by Animal Care and Use Committee of Sun Yat-sen University,China(Zhongshan Medical Ethics 2014 No.23)on September 22,2014. 展开更多
关键词 6-HYDROXYDOPAMINE ASTROCYTE dopamine depletion DOPAMINERGIC neurons Parkinson’s disease SIOOB STAT3 STRIATUM
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Non-sea-salt sulfate in the marine boundary layer and its possible impact on chloride depletion 被引量:1
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作者 Cole-Dai Jihong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第6期162-171,共10页
Aerosol samples were collected on board the research vessel Xuelong during the Fifteenth Chinese Antarctic Research Expedition (CHINARE XV) in November 1998-April 1999 and the First Chinese Arctic Research Expedition ... Aerosol samples were collected on board the research vessel Xuelong during the Fifteenth Chinese Antarctic Research Expedition (CHINARE XV) in November 1998-April 1999 and the First Chinese Arctic Research Expedition in July-September 1999.The areas traversed by the expeditionary cruises include the Arctic Ocean, the western North Pacific Ocean and the eastern Indian Ocean, covering 75°N-69°S and 75°E-133°W. Aerosol samples were also taken at the Chinese Zhongshan Station in East Antarctica during the CHINARE XV. Analysis of the samples yielded concentrations of non-sea-salt sulfate and other soluble chemical species in the marine boundary layer. The data suggest that the chemical composition of the marine aerosols is influenced by three major sources: continental air masses, primary oceanic emissions, and secondary marine aerosols originated from oceanic emissions.The results show that, awing to strong anthropogenic sulfur emissions from the Asian continent, non-sea-salt sulfate concentrations in the Northern Hemisphere (the western North Pacific) marine aerosol are significantly higher than those in the Southern Hemisphere (the eastern Indian Ocean). Aerosol non-sea-salt sulfate concentrations appear to be inversely correlated with aerosol non-sea-salt chloride which shows significantly negative values, indicating the loss of chloride by sea salts, in most aerosol samples. Since gaseous HCl may be involved in chemical reactions that deplete atmospheric ozone in the marine boundary layer (MBL), high levels of acidic non-sea-salt-sulfate released by human activities in the low and mid-latitudes of the Northern Hemisphere may become an important potential contributor to the loss of atmospheric ozone in the MBL. 展开更多
关键词 non-sea-salt SULFATE MARINE BOUNDARY LAYER CHLORIDE depletion
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Depletion of the Ozone Layer and Its Consequences: A Review 被引量:2
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作者 Anjali Aggarwal Reeta Kumari +8 位作者 Neeti Mehla   Deepali Rishi Pal Singh Sonal Bhatnagar Kameshwar Sharma Kuldeep Sharma Vashishtha Amit Brijesh Rathi 《American Journal of Plant Sciences》 2013年第10期1990-1997,共8页
Ozone (O3) is a stratospheric layer that plays important role in providing support to humans for their survival. It is an essential factor for many global, biological and environmental phenomena. The ultra-violet (UV)... Ozone (O3) is a stratospheric layer that plays important role in providing support to humans for their survival. It is an essential factor for many global, biological and environmental phenomena. The ultra-violet (UV) rays emitted from sun are captured by ozone and thereby provide a stable ontological structure in the biosphere. Various anthropogenic activities such as emissions of CFCs, HCFCs and other organo-halogens lead to the depletion of ozone. The ozone depletion resulted in secondary production of an ozone layer near the ground (terrestrial ozone layer), which is responsible for adverse effects on plants, humans and environment with increased number of bronchial diseases in humans. The mutations caused by UV rays result in variation in morphogenic traits of plants which ultimately decreases crop productivity. However, UV radiation is required in optimum intensity for both plants and animals. This review takes into an account the wide ranging effects of ozone depletion with a majority of them being detrimental to the plant system. 展开更多
关键词 OZONE depletion Ultra-Violet RADIATION CHLOROFLUOROCARBONS PLANTS ECOSYSTEM
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Don’t know what you got till it’s gone:microglial depletion and neurodegeneration 被引量:1
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作者 David Graykowski Eiron Cudaback 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第10期1921-1927,共7页
In the central nervous system,immunologic surveillance and response are carried out,in large part,by microglia.These resident macrophages derive from myeloid precursors in the embryonic yolk sac,migrating to the brain... In the central nervous system,immunologic surveillance and response are carried out,in large part,by microglia.These resident macrophages derive from myeloid precursors in the embryonic yolk sac,migrating to the brain and eventually populating local tissue prior to blood-brain barrier formation.Preserved for the duration of lifespan,microglia serve the host as more than just a central arm of innate immunity,also contributing significantly to the development and maintenance of neurons and neural networks,as well as neuroregeneration.The critical nature of these varied functions makes the characterization of key roles played by microglia in neurodegenerative disorders,especially Alzheimer’s disease,of paramount importance.While genetic models and rudimentary pharmacologic approaches for microglial manipulation have greatly improved our understanding of central nervous system health and disease,significant advances in the selective and near complete in vitro and in vivo depletion of microglia for neuroscience application continue to push the boundaries of research.Here we discuss the research efficacy and utility of various microglial depletion strategies,including the highly effective CSF1R inhibitor models,noteworthy insights into the relationship between microglia and neurodegeneration,and the potential for therapeutic repurposing of microglial depletion and repopulation. 展开更多
关键词 Alzheimer’s disease clodronate liposomes CSF1R depletion microglia NEURODEGENERATION NEUROREGENERATION REPOPULATION
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Indigenous arbuscular mycorrhizal fungi play a role in phosphorus depletion in organic manure amended high fertility soil 被引量:1
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作者 HUO Wei-ge CHAI Xiao-fen +3 位作者 WANG Xi-he William David BATCHELOR Arjun KAFLE FENG Gu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第10期3051-3066,共16页
The species richness and propagule number of arbuscular mycorrhizal fungi(AMF)are high in intensively-managed agricultural soils.Past research has shown that AMF improve crop phosphorus(P)uptake under low soil P condi... The species richness and propagule number of arbuscular mycorrhizal fungi(AMF)are high in intensively-managed agricultural soils.Past research has shown that AMF improve crop phosphorus(P)uptake under low soil P conditions,however it is unclear if AMF play a role in high Olsen-P soils.In this study,we investigated whether native fungal benefits exist under high P input field conditions in-situ and contribute to P utilization.We installed in-grow tubes which were sealed with different membrane pore sizes(30 or 0.45μm)to allow or prevent AMF hyphae access to the hyphal compartment and prevent cotton roots from penetrating the chamber.We used the depletion of soil available P(Olsen-P)in the hyphae accessed compartment to indicate P uptake by the native AMF community.Our results showed that the native AMF mediated P depletion and microbial biomass P(MBP)turnover and caused the largest Olsen-P depletion ratio and MBP turnover ratio in the high P treatments(Olsen-P:78.29 mg kg^(-1)).The cotton roots in each fertilization regime were colonized by a unique AMF community and Glomus and Paraglomus were the dominant genera,implying the longterm fertilization regimes domesticated the AMF community.We conclude that native AMF caused the P depletion and P turnover even under high soil Olsen-P conditions. 展开更多
关键词 arbuscular mycorrhizal fungi phosphorus depletion high P soil Gossypium spp. indigenous community mesh cores
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Effect of Kupffer cells depletion on ABC phenomenon induced by Kupffer cells-targeted liposomes 被引量:1
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作者 Chaoyang Lai Cong Li +6 位作者 Mengyang Liu Qiujun Qiu Xiang Luo Xinrong Liu Ling Hu Yihui Deng Yanzhi Song 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2019年第4期455-464,共10页
Accelerated blood clearance(ABC) phenomenon is common in many PEGylated nanocarriers, whose mechanism has not been completely elucidated yet. In this study, the correlation between Kupffer cells(KCs) and ABC phenomeno... Accelerated blood clearance(ABC) phenomenon is common in many PEGylated nanocarriers, whose mechanism has not been completely elucidated yet. In this study, the correlation between Kupffer cells(KCs) and ABC phenomenon has been studied by KCs-targeted liposomes inducing ABC phenomenon and KCs depletion. In other words, the 4-aminophenyl-α-D-mannopyranoside(APM) lipid derivative DSPE-PEG 2000-APM(DPM), and 4-aminophenyl-β-L-fucopyranoside(APF) lipid derivative DSPE-PEG 2000-APF(DPF) were conjugated and modified on alendronate sodium(AD) liposomes to specifically target and deplete KCs. The dualligand modified PEGylated liposomes(MFPL) showed stronger ability to damage KCs in vitro and in vivo, which also could indirectly illustrate that dual-ligand modification could better target KCs. Besides, the hepatic biodistribution and pharmacokinetics could directly prove that MFPL had a stronger targeting ability to KCs. In addition, in depletion rats, plasma concentration and splenic biodistribution of MFPL and PEGylated liposomes(PL) were significantly elevated and hepatic biodistribution was significantly reduced, which demonstrated that KCs played an important role on elimination of nanoparticles. What’s more, ABC phenomenon of the secondary injection of PL was stronger in KCs depletion rats than that in normal rats, which indicated that depletion of KCs prolonged the circulation of PL in the first injection repeatedly stimulating B-cells in the marginal region of the spleen and causing it to secrete more IgM antibodies. This could also illustrate that anti-PEG IgM takes up a major station compared with KCs. Most important of all, KCs-targeted liposomes could induce a stronger ABC phenomenon than PL in normal rats, which declared that based on the same IgM concentration, the more the KCs were stimulated, the stronger ABC phenomenon was induced. However, in depletion rats, this difference of ABC phenomenon between PL and MFPL could no more exist, further demonstrating that KCs could participate and play a certain role in the ABC phenomenon. 展开更多
关键词 ACCELERATED BLOOD CLEARANCE (ABC) phenomenon KUPFFER cells depletion Liposomes Bio-distribution
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Aging is associated with cardiac autonomic nerve fiber depletion and reduced cardiac and circulating BDNF levels 被引量:1
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作者 Andrea Elia Alessandro Cannavo +5 位作者 Giuseppina Gambino Maria Cimini Nicola Ferrara Raj Kishore Nazareno Paolocci Giuseppe Rengo 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2021年第7期549-559,共11页
Background Aging is a multifactorial process associated with an impairment of autonomic nervous system(ANS)function.Progressive ANS remodeling includes upregulation of expression of circulating catecholamines and depl... Background Aging is a multifactorial process associated with an impairment of autonomic nervous system(ANS)function.Progressive ANS remodeling includes upregulation of expression of circulating catecholamines and depletion of cardiac autonomic nerve fibers,and it is responsible,in part,for the increased susceptibility to cardiac diseases observed in elderly subjects.Neurotrophic factors,such as brain-derived neurotrophic factor(BDNF)and nerve growth factor(NGF),are involved in synaptogenesis and neurite outgrowth processes,supporting neuronal cell differentiation and maturation.However,whether and how these factors and their downstream signaling are involved in cardiac aging remains unclear.Here,we tested whether,in the aged heart,the overall extent of autonomic fibers is reduced,owing to lower production of trophic factors such as BDNF and NGF.Methods In vivo,we used young(age:3 months;n=10)and old(age:24 months;n=11)male Fisher rats,whereas,we used human neuroblastoma(SH-SY5 Y)cells in vitro.Results Compared to the young rats,old rats displayed a marked reduction in the overall ANS fiber density,affecting both sympathetic and cholinergic compartments,as indicated by dopamineβ-hydroxylase(dβh)and vesicular acetylcholine transporter(Va Ch T)immunohistochemical staining.In addition,a marked downregulation of GAP-43 and BDNF protein was observed in the left ventricular lysates of old rats compared to those of young rats.Interestingly,we did not find any significant difference in cardiac NGF levels between the young and old groups.To further explore the impact of aging on ANS fibers,we treated SH-SY5 Y cells in vitro with serum obtained from young and old rats.Sera from both groups induced a remarkable increase in neuronal sprouting,as evidenced by a crystal violet assay.However,this effect was blunted in cells cultured with old rat serum and was accompanied by a marked reduction in GAP-43 and BDNF protein levels.Conclusions Our data indicate that physiological aging is associated with an impairment of ANS structure and function and that reduced BDNF levels are responsible,at least in part,for these phenomena. 展开更多
关键词 CARDIAC depletion fibers
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Observations of TEC Depletion,Periodic Structure of TEC,ROTI and Scintillation Associated with ESF Irregularities over South China 被引量:1
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作者 DENG Kun MA Yonghui +2 位作者 LIU Minbo GUO Zhixiong WANG Shu 《空间科学学报》 CAS CSCD 北大核心 2020年第3期331-340,共10页
The observations of Global Positioning System(GPS) scintillation,Total Electron Content(TEC)depletion,the periodic structure of TEC and Rate of TEC Index(ROTI) over south China were presented.Data were collected from ... The observations of Global Positioning System(GPS) scintillation,Total Electron Content(TEC)depletion,the periodic structure of TEC and Rate of TEC Index(ROTI) over south China were presented.Data were collected from GPS observations at stations of Shenzhen and Guangzhou from 2011 to 2012.This study reported that the ratio of simultaneous occurrences of TEC depletions with strong scintillations was higher than that of TEC depletions with weak scintillations in vernal and autumnal equinoxes of 2011 over South China.The number of the periodic structures of TEC with depletion contained was greater than that with no depletion contained corresponding to strong scintillations.The structure of the slab of plasma irregularities could be responsible for the simultaneous occurrences of TEC depletion with strong scintillations and ROTI.Before and during the occurrences of strong scintillation,there was Large-Scale Wave Structure(LSWS) which provided the seed ionization perturbation to trigger ESF irregularities and contributed to the periodic structure of TEC. 展开更多
关键词 GPS scintillation Total Electron Content(TEC) TEC depletion Periodic structure of TEC Rate of TEC Index(ROTI)
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Deuterium Depletion May Delay the Progression of Prostate Cancer 被引量:4
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作者 Andras Kovacs Imre Guller +6 位作者 Krisztina Krempels Ildiko Somlyai Istvan Janosi Zoltan Gyongyi Istvan Szabo Istvan Ember Gabor Somlyai 《Journal of Cancer Therapy》 2011年第4期548-556,共9页
Deuterium-depleted water (DDW) is a new promising agent in cancer therapy. The efficiency of the method is based on the discovery, that cancer cells are extremely sensitive to depletion of deuterium (D) and might caus... Deuterium-depleted water (DDW) is a new promising agent in cancer therapy. The efficiency of the method is based on the discovery, that cancer cells are extremely sensitive to depletion of deuterium (D) and might cause necrosis of the tumour. The purpose of this study was to show the efficacy of D-depletion in prostate cancer (PC) patients. In the double blind, four-month-long, randomized Phase II clinical trial the daily water intake was replaced with DDW in 22 PC patients. Other 22 PC patients took normal water while both groups received the same forms of conventional treatment. In the retrospective study, 91 DDW-treated PC patients were evaluated and median survival time (MST) in the subgroups was calculated. The time course of changes in DDW dose and PSA is presented in two cases. In the prospective trial seven patients in the treated group and one patient in the placebo group achieved partial response (p = 0.046). In the treated group, the net decrease in the prostate volume was three times higher (160.3 cm3 vs. 54.0 cm3;p = 0.0019), urination complaints ceased at a higher rate (8 vs. 0 patients, p = 0.0041), and the one-year survival rate was also higher (2 vs. 9 deaths;p = 0.034). The 91 retrospectively evaluated patients achieved an MST of 11.02 years, despite the fact that 46 of them suffered from distant metastasis. In the two monitored patients, drop of PSA level correlated with the DDW intake. In summary, D-depletion prolonged MST in patients with PC. The method proved to be safe thus its integration in the PC cure as an adjuvant or complementary therapy would be considered. 展开更多
关键词 Deuterium depletion DDW Prostate Cancer Phase II Clinical Trial Retrospective Evaluation Median Survival
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Simulation of the Influence of Ion-Produced NO_X and HO_X Radicals on the Antarctic Ozone Depletion with a One-Dimensional Model
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作者 王贵勤 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第1期98-103,共6页
A one -dimensional time-dependent photochemical model is used to simulate the influence of ion-produced NOx and HOx radicals on the Antarctic ozone depletion in polar night and polar spring at a latitude of 73 degrees... A one -dimensional time-dependent photochemical model is used to simulate the influence of ion-produced NOx and HOx radicals on the Antarctic ozone depletion in polar night and polar spring at a latitude of 73 degrees south.Vertical transport and nitrogen-oxygen (NOx). hydrogen-oxygen (HOx) production by ionic reactions have been introduced into the model.NOx and HOx produced by precipitating ions are transported into the lower stratosphere by vertical motion and have some effects in the development of the Antarctic ozone depletion.From winter through spring the calculated ozone column decreases to 269.4 DU. However, this value is significantly higher than the total ozone observed at several Antarctic ozone stations. 展开更多
关键词 OZONE PHOTOCHEMICAL depletion LATITUDE night polar winter IONIC ultraviolet slight
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Biologically effective radiation of solar ultraviolet radiation and the depletion of stratospheric ozone
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作者 Wang Shaobin Su Weihan(Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences),Beijing 100085,China) Wei Dingwen(Institute of Atmospheric Physics,Chinese Academy or Sciences),Beijing 100029,China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1994年第3期373-381,共9页
BiologicallyeffectiveradiationofsolarultravioletradiationandthedepletionofstratosphericozoneWangShaobin;SuWe... BiologicallyeffectiveradiationofsolarultravioletradiationandthedepletionofstratosphericozoneWangShaobin;SuWeihan(ResearchCent... 展开更多
关键词 UV-B OZONE depletion biological effects SOLAR radiation.
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