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Effects of Chlorine and Chlorine Monoxide on Stratospheric Ozone Depletion 被引量:1
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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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Interphase migration and enrichment of lead and zinc during copper slag depletion
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作者 Jun HAO Zhi-he DOU +2 位作者 Xing-yuan WAN Ting-an ZHANG Kun WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期3029-3041,共13页
An interphase migration and enrichment model of lead and zinc during molten copper slag depletion was established.The occurrence of various components in copper slag was predicted using sulfur-oxygen potential calcula... An interphase migration and enrichment model of lead and zinc during molten copper slag depletion was established.The occurrence of various components in copper slag was predicted using sulfur-oxygen potential calculations and confirmed through high-temperature experiments.The recovery rate of copper can reach 90.13%under the optimal conditions of 1200°C,an iron to silicon mass ratio of 1.0,3 wt.%ferrous sulfide,and a duration of 45 min.Lead(54.07 wt.%)and zinc(17.42 wt.%)are found in the flue dust as lead sulfate,lead sulfide,and zinc oxide,while copper matte contains lead(14.44 wt.%)and zinc sulfide(1.29 wt.%).The remaining lead and zinc are encapsulated as oxides within the fayalite phase. 展开更多
关键词 depletion LEAD copper slag STIRRING ZINC
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Phase Transitions and Seepage Characteristics during the Depletion Development of Deep Condensate Gas Reservoirs
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作者 Qiang Liu Rujun Wang +6 位作者 Yintao Zhang Chong Sun Meichun Yang Yuliang Su Wendong Wang Ying Shi Zheng Chen 《Energy Engineering》 EI 2024年第10期2797-2823,共27页
Deep condensate gas reservoirs exhibit highly complex and variable phase behaviors,making it crucial to understand the relationship between fluid phase states and flow patterns.This study conducts a comprehensive anal... Deep condensate gas reservoirs exhibit highly complex and variable phase behaviors,making it crucial to understand the relationship between fluid phase states and flow patterns.This study conducts a comprehensive analysis of the actual production process of the deep condensate gas well A1 in a certain oilfield in China.Combining phase behavior analysis and CMG software simulations,the study systematically investigates phase transitions,viscosity,and density changes in the gas and liquid phases under different pressure conditions,with a reservoir temperature of 165°C.The research covers three crucial depletion stages of the reservoir:single-phase flow,two-phase transition,and two-phase flow.The findings indicate that retrograde condensation occurs when the pressure falls below the dew point pressure,reachingmaximum condensate liquid production at around 25MPa.As pressure decreases,gas phase density and viscosity gradually decrease,while liquid phase density and viscosity show an increasing trend.In the initial single-phase flow stage,maintaining a consistent gas-oil ratio is observed when both bottom-hole and reservoir pressures are higher than the dew point pressure.However,a sudden drop in bottom-hole pressure below the dew point triggers the production of condensate oil,significantly reducing subsequent gas and oil production.In the transitional two-phase flow stage,as the bottom-hole pressure further decreases,the reservoir exhibits a complex flow regime with coexisting areas of gas and liquid.In the subsequent two-phase flow stage,when both bottom-hole and reservoir pressures are below the dew point pressure,a significant increase in the gas-oil ratio is observed.The reservoir manifests a two-phase flow regime,devoid of single-phase gas flow areas.For lowpressure conditions in deep condensate gas reservoirs,considerations include gas injection,gas lift,and cyclic gas injection and production in surrounding wells.Additionally,techniques such as hot nitrogen or CO_(2) injection can be employed to mitigate retrograde condensation damage.The implications of this study are crucial for developing targeted development strategies and enhancing the overall development of deep condensate gas reservoirs. 展开更多
关键词 Deep condensate gas reservoirs depletion development phase behavior percolation laws dynamic production analysis
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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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Peculiar Nonlinear Depletion in Double-Layered Gated Si-δ-Doped GaAs
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作者 卢铁城 林理彬 +2 位作者 M.LEVIN V.GINODMAN I.SHLIMAK 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第5期538-542,共5页
The low-temperature measurement of Hall effect of the two-dimensional electron system in a double-layered gated Si-δ-doped GaAs is presented.A complex peculiar nonlinear dependence of the depletion on gate voltage i... The low-temperature measurement of Hall effect of the two-dimensional electron system in a double-layered gated Si-δ-doped GaAs is presented.A complex peculiar nonlinear dependence of the depletion on gate voltage is observed.The nonlinearity is also explained on the basis of the assumption that the double-capacity model consists of two δ-doped two-dimensional electron layers and a metallic gate,and the experimental result that the electron mobility is linear with the electron density on a log-log scale. 展开更多
关键词 nonlinear depletion double layerd gated Si-δ-doped GaAs
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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... 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. 展开更多
关键词 Nonalcoholic fatty liver disease Iron depletion Randomized controlled trial FERRITIN
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Numerical investigation on the effect of depletion-induced stress reorientation on infill well hydraulic fracture propagation 被引量:6
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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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Impact of Increasing Stratospheric Water Vapor on Ozone Depletion and Temperature Change 被引量:16
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作者 田文寿 Martyn P.CHIPPERFIELD 吕达仁 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第3期423-437,共15页
Using a detailed, fully coupled chemistry climate model (CCM), the effect of increasing stratospheric H20 on ozone and temperature is investigated. Different CCM time-slice runs have been performed to investigate th... Using a detailed, fully coupled chemistry climate model (CCM), the effect of increasing stratospheric H20 on ozone and temperature is investigated. Different CCM time-slice runs have been performed to investigate the chemical and radiative impacts of an assumed 2 ppmv increase in H20. The chemical effects of this H20 increase lead to an overall decrease of the total column ozone (TCO) by ~1% in the tropics and by a maximum of 12% at southern high latitudes. At northern high latitudes, the TCO is increased by only up to 5% due to stronger transport in the Arctic. A 2-ppmv H2O increase in the model's radiation scheme causes a cooling of the tropical stratosphere of no more than 2 K, but a cooling of more than 4 K at high latitudes. Consequently, the TCO is increased by about 2%-6%. Increasing stratospheric H2O, therefore, cools the stratosphere both directly and indirectly, except in the polar regions where the temperature responds differently due to feedbacks between ozone and H2O changes. The combined chemical and radiative effects of increasing H2O may give rise to more cooling in the tropics and middle latitudes but less cooling in the polar stratosphere. The combined effects of H2O increases on ozone tend to offset each other, except in the Arctic stratosphere where both the radiative and chemical impacts give rise to increased ozone. The chemical and radiative effects of increasing H2O cause dynamical responses in the stratosphere with an evident hemispheric asymmetry. In terms of ozone recovery, increasing the stratospheric H2O is likely to accelerate the recovery in the northern high latitudes and delay it in the southern high latitudes. The modeled ozone recovery is more significant between 2000 ~2050 than between 2050~2100, driven mainly by the larger relative change in chlorine in the earlier period. 展开更多
关键词 stratospheric water vapor temperature change ozone depletion chemistry-climate model
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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 ionosphericF-region have been simulated numerically by means of a physical model. It is found that an enhancement of electric fiel... THe effects of strong convection electric field on the electron density in the auroral ionosphericF-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 theF 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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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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Effects of unsymmetrical geometric confinements on depletion interactions in colloidal suspensions 被引量:3
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作者 郭纪源 黄立新 肖长明 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第7期1638-1644,共7页
The depletion interactions between two large-spheres immersed in a fluid of small spheres under unsymmetrical geometrical confinement are studied through the acceptance ratio method. The numerical results show that no... The depletion interactions between two large-spheres immersed in a fluid of small spheres under unsymmetrical geometrical confinement are studied through the acceptance ratio method. The numerical results show that no matter whether the volume fraction is large or small, both the depletion potential and depletion force are affected by the presence of the two plates; the closer the two large spheres are to the plate, the larger the effects of the unsymmetrical confinements. 展开更多
关键词 depletion interactions COLLOIDAL acceptance ratio method
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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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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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Aging is associated with cardiac autonomic nerve fiber depletion and reduced cardiac and circulating BDNF levels 被引量:3
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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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Indigenous arbuscular mycorrhizal fungi play a role in phosphorus depletion in organic manure amended high fertility soil 被引量:2
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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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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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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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