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Changes and Restrictions
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作者 Ruan Zongze is a Research Professor and Deputy Director of China Institute of International Studies. 《Contemporary International Relations》 2003年第9期47-52,共6页
The development of the United States of America in its history over the past more than 200 years demonstrates that, the strategic line of thought of this nation is rather clear. In other words, America is a "nati... The development of the United States of America in its history over the past more than 200 years demonstrates that, the strategic line of thought of this nation is rather clear. In other words, America is a "nation that is never content. " This can be seen from its development from thirteen colonies to a big power stretching cross two oceans, then the only superpower in today’s world. The words and deeds of U. S. important political figures and public opinions as well reveal that at pre- 展开更多
关键词 that HAVE Changes and restrictions into of from been OPEC THAN
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Modelling the Violation of Restrictions Pertaining to Deforestation in a Given Land Right
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作者 Anthony G. Tumba Shahidah Bte Mohd Ariff 《Journal of Environmental Protection》 2015年第11期1219-1235,共17页
This paper develops a model that could be used to visualize and predict the violation of restrictions in a given forest. The violation of restriction in this case is assumed to be the difference in areal extent betwee... This paper develops a model that could be used to visualize and predict the violation of restrictions in a given forest. The violation of restriction in this case is assumed to be the difference in areal extent between two forest cover scenes with time;termed “deforestation”. It analyses the relationship in forest cover changes overtime in Ganye Forest Reserve and Glide Cross Country Farm in Adamawa state, Nigeria. Cadastral maps of the forest reserve and farmland were used as the base maps, while the satellite images served as the spatio-temporal data. Landsat ETM+ images of 2003, 2008 and 2013 were used to identify, determine and estimate the violation of restrictions. The result shows that the violation of restrictions could be reliably determined for both the forest reserve and farmland and forecast made in order to predict future occurrence. It also revealed a continuous deforestation in the forest reserve, while in the farmland regeneration of forest stock was noticed. This information is very vital for forest management, planning and decision making in a viable land administration domain. 展开更多
关键词 VIOLATION of restrictions DEFORESTATION MODEL LAND RIGHT
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Necessary Conditions for Optimal Control of Diffusions with Hard Terminal State Restrictions
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作者 Atle Seierstad 《Open Journal of Optimization》 2018年第1期1-40,共40页
Necessary conditions are proved for certain problems of optimal control of diffusions where hard end constraints occur. The main results apply to several dimensional problems, where some of the state equations involve... Necessary conditions are proved for certain problems of optimal control of diffusions where hard end constraints occur. The main results apply to several dimensional problems, where some of the state equations involve Brownian motions, but not the equations corresponding to states being hard restricted at the terminal time. The necessary conditions are stated in terms of weak variations. Two versions of necessary conditions are given, one version involving solutions of variational equations, the other one involving first order adjoint equations. 展开更多
关键词 OPTIMAL Control DIFFUSIONS HARD TERMINAL STATE restrictions
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Measuring the Social Net Benefits of COVID-19 Restrictions: The Case of Reduced Vehicle Use in a Pollution-Prone Region of Utah
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作者 Ethan Hartley Arthur J. Caplan 《Journal of Environmental Protection》 2021年第11期887-902,共16页
A number of natural experiments have recently found that COVID-19 restrictions imposed in nations worldwide are correlated with short-term reductions—in some cases dramatic reductions—in mobile-source air pollutants... A number of natural experiments have recently found that COVID-19 restrictions imposed in nations worldwide are correlated with short-term reductions—in some cases dramatic reductions—in mobile-source air pollutants. Noticeably absent from these studies are estimates of the social net benefits associated with the changes in human behavior underlying the pandemic-induced effects. Using readily available data provided by the state of Utah and the U.S. Environmental Protection Agency’s Co-Benefits Risk Assessment Health Impacts Screening and Mapping Tool (COBRA), we find that daily social net benefit was positive during a pandemic-induced shutdown from March to April, 2020 in Utah’s Wasatch Front region solely when COBRA’s “high” health benefit estimate from combined reductions in PM<sub>2.5</sub> and NO<sub>x</sub> concentrations are weighed against the region’s “low” vehicle-trip cost estimate. All other scenarios correspond with negative net benefit estimates, <i>i.e.</i>, when high and low benefit estimates of reductions solely in PM<sub>2.5</sub> concentrations as well as for combined reductions in PM<sub>2.5</sub> and NO<sub>x</sub> concentrations are weighed against the region’s high vehicle-trip cost estimate. Generally speaking, social net benefits are higher for two of the Wasatch Front’s four counties. 展开更多
关键词 Social Net Benefits COVID-19 restrictions Mobile-Source Air Pollution
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Imposing Restrictions on Hazardous Substances in Plastics
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《Bulletin of the Chinese Academy of Sciences》 2018年第4期232-234,共3页
With the support of the Academic Division of the Chinese Academy of Sciences, a task force headed by Prof. DUAN Xue, a CAS Member from Beijing University of Chemical Technology, has conducted studies on the developmen... With the support of the Academic Division of the Chinese Academy of Sciences, a task force headed by Prof. DUAN Xue, a CAS Member from Beijing University of Chemical Technology, has conducted studies on the development of safe plastics. 展开更多
关键词 IMPOSING restrictions Hazardous Substances PLASTICS
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Should There Be Legal Restrictions on Children’s Names?
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《ChinAfrica》 2018年第2期12-13,共2页
A recent spate of controversial names have steered public debate toward people's rights when naming their children.In late 2017,the story of a newborn girl in Xi'an named"Wang Zherongyao,"or King of Glorly,after a... A recent spate of controversial names have steered public debate toward people's rights when naming their children.In late 2017,the story of a newborn girl in Xi'an named"Wang Zherongyao,"or King of Glorly,after a popular online game,went viral. 展开更多
关键词 Should There Be Legal restrictions on Children’s Names BE
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Effects of restrictions on maternal feed intake on the immune indexes of umbilical cord blood and liver Toll-like receptor signaling pathways in fetal goats during pregnancy 被引量:3
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作者 Wenxun Chen Qiongxian Yan +2 位作者 Hong Yang Xiaoling Zhou Zhiliang Tan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第3期736-744,共9页
Background: Liver has important immune function during fetal development and after birth.However,the effect of maternal malnutrition on immune function of the fetal liver is rarely reported.In this study,twelve pregna... Background: Liver has important immune function during fetal development and after birth.However,the effect of maternal malnutrition on immune function of the fetal liver is rarely reported.In this study,twelve pregnant goats(Xiangdong black goat,at d 45 of gestation) were assigned to the control group(fed 100% of nutritional requirements) and the restriction group(fed 60% of the intake of the control group) during gestation from d 55 to100.Fetal goats were harvested at d 100 of gestation and immune indexes and amino acid profiles of the umbilical cord blood and liver Toll-like receptors(TLRs) signaling pathways were measured.Results: Maternal body weight in the restriction group was lower than the control group(P < 0.05).Maternal feed intake restriction decreased(P < 0.05) heart weight,heart index,alkaline phosphatase and serum amyloid protein A in the umbilical cord blood(UCB).Moreover,only histidine was decreased in the restricted group(P = 0.084),and there were no differences in other amino acids contents in the UCB between the two groups(P > 0.05).The TLR2 and TLR4 mRNA expression in the fetal liver in the restriction group was greater(P < 0.05) than that in the control group.Furthermore,the mRNA expression levels of myeloid differentiation primary response 88(MyD88),TNF receptor associated factor 6,nuclear factor kappa B subunit 1,NFKB inhibitor alpha,IFN-β,TGF-β,TNF-α and IL-1β in the restricted group were upregulated(P < 0.05),and the expression of TLR3(P = 0.099) tended to be higher in the restricted group.However,protein levels of TLR2,TLR4,IκBα,phosphorylated IκBα,phosphorylated IκBα/total IκBα,TRIF and MyD88 were not affected(P > 0.05) by maternal intake restriction.Conclusions: These results revealed that the restriction of maternal feed intake influenced the development of heart and hepatic protein synthesis at the acute phase of fetal goats and upregulated the mRNA expression of genes involved in MyD88-dependent signaling pathways and of target cytokines. 展开更多
关键词 Feed INTAKE RESTRICTION FETAL goats Immune cell LIVER TLRS signaling pathway
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Assessing the Effect of Global Travel and Contact Restrictions on Mitigating the COVID-19 Pandemic 被引量:3
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作者 Shengjie Lai Nick W.Ruktanonchai +7 位作者 Alessandra Carioli Corrine W.Ruktanonchai Jessica R.Floyd Olivia Prosper Chi Zhang Xiangjun Du Weizhong Yang Andrew J.Tatem 《Engineering》 SCIE EI 2021年第7期914-923,共10页
Travel restrictions and physical distancing have been implemented across the world to mitigate the coronavirus disease 2019(COVID-19)pandemic,but studies are needed to understand their effectiveness across regions and... Travel restrictions and physical distancing have been implemented across the world to mitigate the coronavirus disease 2019(COVID-19)pandemic,but studies are needed to understand their effectiveness across regions and time.Based on the population mobility metrics derived from mobile phone geolocation data across 135 countries or territories during the first wave of the pandemic in 2020,we built a metapopulation epidemiological model to measure the effect of travel and contact restrictions on containing COVID-19 outbreaks across regions.We found that if these interventions had not been deployed,the cumulative number of cases could have shown a 97-fold(interquartile range 79–116)increase,as of May 31,2020.However,their effectiveness depended upon the timing,duration,and intensity of the interventions,with variations in case severity seen across populations,regions,and seasons.Additionally,before effective vaccines are widely available and herd immunity is achieved,our results emphasize that a certain degree of physical distancing at the relaxation of the intervention stage will likely be needed to avoid rapid resurgences and subsequent lockdowns. 展开更多
关键词 COVID-19 PANDEMIC Population mobility Travel restriction Physical distancing
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Improvement of the Preliminary Test Estimator When Stochastic Restrictions are Available in Linear Regression Model 被引量:1
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作者 Sivarajah Arumairajan Pushpakanthie Wijekoon 《Open Journal of Statistics》 2013年第4期283-292,共10页
Ridge type estimators are used to estimate regression parameters in a multiple linear regression model when multicolinearity exists among predictor variables. When different estimators are available, preliminary test ... Ridge type estimators are used to estimate regression parameters in a multiple linear regression model when multicolinearity exists among predictor variables. When different estimators are available, preliminary test estimation procedure is adopted to select a suitable estimator. In this paper, two ridge estimators, the Stochastic Restricted Liu Estimator and Liu Estimator are combined to define a new preliminary test estimator, namely the Preliminary Test Stochastic Restricted Liu Estimator (PTSRLE). The stochastic properties of the proposed estimator are derived, and the performance of PTSRLE is compared with SRLE in the sense of mean square error matrix (MSEM) and scalar mean square error (SMSE) for the two cases in which the stochastic restrictions are correct and not correct. Moreover the SMSE of PTSRLE based on Wald (WA), Likelihood Ratio (LR) and Lagrangian Multiplier (LM) tests are derived, and the performance of PTSRLE is compared using WA, LR and LM tests as a function of the shrinkage parameter d with respect to the SMSE. Finally a numerical example is given to illustrate some of the theoretical findings. 展开更多
关键词 Preliminary TEST ESTIMATOR Mean SQUARE ERROR Matrix Scalar Mean SQUARE ERROR STOCHASTIC Restricted LIU ESTIMATOR LIU ESTIMATOR Wald TEST Likelihood Ratio TEST Lagrangian Multiplier TEST
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Restrictions on Purely Kinetic K-Essence
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作者 杨荣佳 祁景钊 杨宝柱 《Chinese Physics Letters》 SCIE CAS CSCD 2011年第10期296-298,共3页
We restrict purely kinetic k-essence.Assuming that the equation of state is a power law of the kinetic energy,i.e.w=w0Xα,we find thatαmust be positive to obtain accelerated phases,constrained from the conditions for... We restrict purely kinetic k-essence.Assuming that the equation of state is a power law of the kinetic energy,i.e.w=w0Xα,we find thatαmust be positive to obtain accelerated phases,constrained from the conditions for stability and causality.In this case the k-essence behaves like a phantom.We also study the evolutions of the equation of state and the speed of sound with numerical simulations. 展开更多
关键词 KINETIC purely restrict
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Urban Land Use Efficiency and Contributing Factors in the Yangtze River Delta Under Increasing Environmental Restrictions in China
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作者 YANG Qingke WANG Lei +3 位作者 QIN Xianhong FAN Yeting WANG Yazhu DING Linlin 《Chinese Geographical Science》 SCIE CSCD 2022年第5期883-895,共13页
Evaluating urban land use efficiency(ULUE) provides insights into the interactions between land use systems and their external environment. Specifically, changes in ULUE are important for monitoring urban transformati... Evaluating urban land use efficiency(ULUE) provides insights into the interactions between land use systems and their external environment. Specifically, changes in ULUE are important for monitoring urban transformation in developing countries. In this study, using a traditional input-output index model, we incorporated slack-based measurements and undesirable outputs into a SBM-UN(slack-based measure-undesirable) model to investigate ULUE within the context of increasing environmental restrictions in China. The model was used to estimate the ULUE of 26 cities in the highly developed urban agglomeration of the Yangtze River Delta from 2000 to2018. The average ULUE in the Yangtze River Delta was relatively low compared to that of developed city regions in the European Union(EU) and North America and exhibited a U-shaped curve over the study period. Incorporating undesirable outputs, such as environmental pollution, into the model reduced ULUE by 19.06%. ULUE varied spatially, with the kernel density estimation exhibiting a bimodal distribution. Efficiency decomposition analysis showed that scale efficiency made a greater contribution to ULUE than pure technical efficiency. Based on our findings, recommended approaches to improve ULUE include optimizing factor allocation, reducing undesirable outputs, and increasing the effective output per land unit. The study suggests that ULUE and the SBM-UN model are useful planning tools for sustainable urban development. 展开更多
关键词 urban land use efficiency(ULUE) environmental restriction efficiency decomposition kernel density estimation SBM-UN(slack-based measure-undesirable)model Yangtze River Delta China
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Quadratic Loss of Isotonic Normal Means under Simultaneous Order Restrictions
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作者 马艳萍 史宁中 《Northeastern Mathematical Journal》 CSCD 2002年第3期245-253,共9页
For two normal populations with unknown means μ and unknown variances σ2, assume that there are simple order restrictions among the means and variances: μ1 < μ2 and σ12 >σ22 > 0. This case is said to be... For two normal populations with unknown means μ and unknown variances σ2, assume that there are simple order restrictions among the means and variances: μ1 < μ2 and σ12 >σ22 > 0. This case is said to be simultaneous order restriction by Shi (Maximum likelihood estimation of means and variances from normal populations under simultaneous order restrictions, J. Multivariate Anal., 50(1994), 282-293.) and an iterative algorithm of computing the order restricted maximum likelihood estimates of μi and σi2 was given in that paper. This paper shows that the restricted maximum likelihood estimate of μi has smaller mean square loss than the usual estimate xi under some conditions. 展开更多
关键词 isotonic regression mean square loss restricted maximum likelihood estimate
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A Matrix Inequality for the Inversions of the Restrictions of a Positive Definite Hermitian Matrix
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作者 Weixiong Mai Mo Yan +2 位作者 Tao Qian Matteo Dalla Riva Saburou Saitoh 《Advances in Linear Algebra & Matrix Theory》 2013年第4期55-58,共4页
We exploit the theory of reproducing kernels to deduce a matrix inequality for the inverse of the restriction of a positive definite Hermitian matrix.
关键词 Reproducing Kernel POSITIVE Definite HERMITIAN MATRIX Quadratic Inequality Inversion of POSITIVE Definite HERMITIAN MATRIX Restriction of POSITIVE Definite HERMITIAN MATRIX SCHUR Complement Block MATRIX
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Flowering on Time: Multilayered Restrictions on FT in Plants 被引量:3
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作者 Qin, Zhengrui Bai, Yuxue Wu, Liang 《Molecular Plant》 SCIE CAS CSCD 2017年第11期1365-1367,共3页
The successful transition from vegetative to reproductive growth directly influences plant biomass and fitness. The regulation of flowering time has been investigated for over two decades, with several molecular modul... The successful transition from vegetative to reproductive growth directly influences plant biomass and fitness. The regulation of flowering time has been investigated for over two decades, with several molecular modules having been characterized, functioning in the photoperiod, vernalization, autonomous, aging, or phytohormone pathways. Although the upstream components of these flowering pathways differ among plant species, most endogenous and external cues are ultimately integrated to control a highly conserved protein, FLOWERING LOCUS T (FT), to ensure that flowering is initiated at an appropriate time. 展开更多
关键词 Flowering on Time Multilayered restrictions FT in Plants
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The Impacts of Trade Restrictions on World Agricultural Price Volatility during the COVID-19 Pandemic 被引量:2
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作者 Wenshou Yan Yan Cai +1 位作者 Faqin Lin Dessie Tarko Ambaw 《China & World Economy》 2021年第6期139-158,共20页
During the COVID-19 pandemic,countries applied trade restrictions to insulate their domestic markets from the world market.However,these trade policies could have amplified international market price fluctuations.This... During the COVID-19 pandemic,countries applied trade restrictions to insulate their domestic markets from the world market.However,these trade policies could have amplified international market price fluctuations.This paper explores the effects of trade restrictions on international agricultural price volatility.A theoretical model is developed to quantify how trade policies amplify the initial shock.Using panel data covering 71 countries from January 2020 to July 2021,we examine empirically the effects of trade policies on world agricultural price volatility.The results show that trade distortions further induced volatility of world agricultural prices by around 22 percent during the COVID-19 pandemic.The multiplier effects are much more substantial in agricultural exporting countries than in importing countries.Large countries like China and the US could make significant contributions to stabilizing world prices by limiting the extent of unilateral trade policy interventions. 展开更多
关键词 agricultural price volatility COVID-19 multiplier effect trade restrictions
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Concerns about the application of resistance exercise with blood-flow restriction and thrombosis risk in hemodialysis patients
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作者 Hugo de Luca Correa Lysleine Alves Deus +15 位作者 Dahan da Cunha Nascimento Nicholas Rolnick Rodrigo Vanerson Passos Neves Andrea Lucena Reis Thais Branquinho de Araujo Carmen Tzanno-Martins Fernanda Silveira Tavares Luiz Sinesio Silva Neto Claudio Avelino Rodrigues Santos Paolo Lucas Rodrigues-Silva Fernando Honorato Souza Vitoria Marra da Motta Vilalva Mestrinho Rafael Lavarini dos Santos Rosangela Vieira Andrade Jonato Prestes Thiago dos Santos Rosa 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第4期548-558,F0003,共12页
Background:Hemodialysis(HD)per se is a risk factor for thrombosis.Considering the growing body of evidence on blood-flow restriction(BFR)exercise in HD patients,identification of possible risk factors related to the p... Background:Hemodialysis(HD)per se is a risk factor for thrombosis.Considering the growing body of evidence on blood-flow restriction(BFR)exercise in HD patients,identification of possible risk factors related to the prothrombotic agent D-dimer is required for the safety and feasibility of this training model.The aim of the present study was to identify risk factors associated with higher D-dimer levels and to determine the acute effect of resistance exercise(RE)with BFR on this molecule.Methods:Two hundred and six HD patients volunteered for this study(all with a glomerular filtration rate of<15 mL/min/1.73 m^(2)).The RE+BFR session consisted of 50%arterial occlusion pressure during 50 min sessions of HD(intradialytic exercise).RE repetitions included concentric and eccentric lifting phases(each lasting 2 s)and were supervised by a strength and conditioning specialist.Results:Several variables were associated with elevated levels of D-dimer,including higher blood glucose,citrate use,recent cardiovascular events,recent intercurrents,higher inflammatory status,catheter as vascular access,older patients(>70 years old),and HD vintage.Furthermore,RE+BFR significantly increases D-dimer after 4 h.Patients with borderline baseline D-dimer levels(400-490 ng/mL)displayed increased risk of elevating D-dimer over the normal range(-500 ng/mL).Conclusion:These results identified factors associated with a heightened prothrombotic state and may assist in the screening process for HD patients who wish to undergo RE+BFR.D-dimer and/or other fibrinolysis factors should be assessed at baseline and throughout the protocol as a precautionary measure to maximize safety during RE+BFR. 展开更多
关键词 Blood-flow restriction Chronic kidney disease COAGULATION HEMODIALYSIS Vascular occlusion exercises
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Mechanisms underlying the role of endoplasmic reticulum stress in the placental injury and fetal growth restriction in an ovine gestation model
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作者 Hao Zhang Xia Zha +5 位作者 Yi Zheng Xiaoyun Liu Mabrouk Elsabagh Hongrong Wang Honghua Jiang Mengzhi Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期201-217,共17页
Background Exposure to bisphenol A(BPA),an environmental pollutant known for its endocrine-disrupting properties,during gestation has been reported to increase the risk of fetal growth restriction(FGR)in an ovine mode... Background Exposure to bisphenol A(BPA),an environmental pollutant known for its endocrine-disrupting properties,during gestation has been reported to increase the risk of fetal growth restriction(FGR)in an ovine model of pregnancy.We hypothesized that the FGR results from the BPA-induced insufficiency and barrier dysfunction of the placenta,oxidative stress,inflammatory responses,autophagy and endoplasmic reticulum stress(ERS).However,precise mechanisms underlying the BPA-induced placental dysfunction,and subsequently,FGR,as well as the potential involvement of placental ERS in these complications,remain to be investigated.Methods In vivo experiment,16 twin-pregnant(from d 40 to 130 of gestation)Hu ewes were randomly distributed into two groups(8 ewes each).One group served as a control and received corn oil once a day,whereas the other group received BPA(5 mg/kg/d as a subcutaneous injection).In vitro study,ovine trophoblast cells(OTCs)were exposed to 4 treatments,6 replicates each.The OTCs were treated with 400μmol/L BPA,400μmol/L BPA+0.5μg/m L tunicamycin(Tm;ERS activator),400μmol/L BPA+1μmol/L 4-phenyl butyric acid(4-PBA;ERS antagonist)and DMEM/F12 complete medium(control),for 24 h.Results In vivo experiments,pregnant Hu ewes receiving the BPA from 40 to 130 days of pregnancy experienced a decrease in placental efficiency,progesterone(P4)level and fetal weight,and an increase in placental estrogen(E2)level,together with barrier dysfunctions,OS,inflammatory responses,autophagy and ERS in type A cotyledons.In vitro experiment,the OTCs exposed to BPA for 24 h showed an increase in the E2 level and related protein and gene expressions of autophagy,ERS,pro-apoptosis and inflammatory response,and a decrease in the P4 level and the related protein and gene expressions of antioxidant,anti-apoptosis and barrier function.Moreover,treating the OTCs with Tm aggravated BPA-induced dysfunction of barrier and endocrine(the increased E2 level and decreased P4 level),OS,inflammatory responses,autophagy,and ERS.However,treating the OTCs with 4-PBA reversed the counteracted effects of Tm mentioned above.Conclusions In general,the results reveal that BPA exposure can cause ERS in the ovine placenta and OTCs,and ERS induction might aggravate BPA-induced dysfunction of the placental barrier and endocrine,OS,inflammatory responses,and autophagy.These data offer novel mechanistic insights into whether ERS is involved in BPA-mediated placental dysfunction and fetal development. 展开更多
关键词 AUTOPHAGY Bisphenol A Endoplasmic reticulum stress Fetal growth restriction Inflammatory responses SHEEP
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Cooperative UAV search strategy based on DMPC-AACO algorithm in restricted communication scenarios
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作者 Shiyuan Chai Zhen Yang +3 位作者 Jichuan Huang Xiaoyang Li Yiyang Zhao Deyun Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期295-311,共17页
Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research pr... Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research problem.In certain mission environments,due to the impact of many interference sources on real-time communication or mission requirements such as the need to implement communication regulations,the mission stages are represented as a dynamic combination of several communication-available and communication-unavailable stages.Furthermore,the data interaction between unmanned aerial vehicles(UAVs)can only be performed in specific communication-available stages.Traditional cooperative search algorithms cannot handle such situations well.To solve this problem,this study constructed a distributed model predictive control(DMPC)architecture for a collaborative control of UAVs and used the Voronoi diagram generation method to re-plan the search areas of all UAVs in real time to avoid repetition of search areas and UAV collisions while improving the search efficiency and safety factor.An attention mechanism ant-colony optimization(AACO)algorithm is proposed for UAV search-control decision planning.The search strategy is adaptively updated by introducing an attention mechanism for regular instruction information,a priori information,and emergent information of the mission to satisfy different search expectations to the maximum extent.Simulation results show that the proposed algorithm achieves better search performance than traditional algorithms in restricted communication constraint scenarios. 展开更多
关键词 Unmanned aerial vehicles(UAV) Cooperative search Restricted communication Mission planning DMPC-AACO
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Age-related driving mechanisms of retinal diseases and neuroprotection by transcription factor EB-targeted therapy
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作者 Samuel Abokyi Dennis Yan-yin Tse 《Neural Regeneration Research》 SCIE CAS 2025年第2期366-377,共12页
Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecu... Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecular underpinnings of their development.This comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches,focusing on the activation of transcription factor EB.Recent meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies,such as exercise,calorie restriction,rapamycin,and metformin,in patients and animal models of these common retinal diseases.The review critically assesses the role of transcription factor EB in retinal biology during aging,its neuroprotective effects,and its therapeutic potential for retinal disorders.The impact of transcription factor EB on retinal aging is cell-specific,influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing pathways.In vascular endothelial cells,transcription factor EB controls important processes,including endothelial cell proliferation,endothelial tube formation,and nitric oxide levels,thereby influencing the inner blood-retinal barrier,angiogenesis,and retinal microvasculature.Additionally,transcription factor EB affects vascular smooth muscle cells,inhibiting vascular calcification and atherogenesis.In retinal pigment epithelial cells,transcription factor EB modulates functions such as autophagy,lysosomal dynamics,and clearance of the aging pigment lipofuscin,thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in neovascularization.These cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis,neuronal synapse plasticity,energy metabolism,microvasculature,and inflammation,ultimately offering protection against retinal aging and diseases.The review emphasizes transcription factor EB as a potential therapeutic target for retinal diseases.Therefore,it is imperative to obtain well-controlled direct experimental evidence to confirm the efficacy of transcription factor EB modulation in retinal diseases while minimizing its risk of adverse effects. 展开更多
关键词 age-related macular degeneration anti-aging interventions autophagy calorie restriction diabetic retinopathy exercise glaucoma NEUROMODULATION PHAGOCYTOSIS photoreceptor outer segment degradation retinal aging transcription factor EB
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Intermittent fasting boosts antitumor immunity by restricting CD11b^(+)Ly6C^(low)Ly6G^(low) cell viability through glucose metabolism in murine breast tumor model
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作者 Chenghao Fu Zhehao Liang +13 位作者 Zemiao Niu Ning Chen Yuemin Li Zhenhua Liang Yanwei Huo Hao Xi Rong Wang Yonghuan Yan Xiaoruo Gan Mengtian Wang Yun Huang Yan Zhang Mingming Gao Pin Lü 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2327-2345,共19页
Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy.However,it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting.Herein we observed ... Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy.However,it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting.Herein we observed that two cycles of fasting treatment significantly inhibited breast tumor growth and lung tissue metastasis,as well as prolonged overall survival in mice bearing 4T1 and 4T07 breast cancer.During this process,both the immunosuppressive monocytic-(M-)and granulocytic-(G-)myeloid-derived suppressor cell(MDSC)decreased,accompanied by an increase in interleukin(IL)7R^(+)and granzyme B^(+)T cells in the tumor microenvironment.Interestingly,we observed that Ly6G^(low)G-MDSC sharply decreased after fasting treatment,and the cell surface markers and protein mass spectrometry data showed potential therapeutic targets.Mechanistic investigation revealed that glucose metabolism restriction suppressed the splenic granulocytemonocyte progenitor and the generation of colony-stimulating factors and IL-6,which both contributed to the accumulation of G-MDSC.On the other hand,glucose metabolism restriction can directly induce the apoptosis of Ly6G^(low)G-MDSC,but not Ly6G^(high)subsets.In summary,these results suggest that glucose metabolism restriction induced by fasting treatment attenuates the immune-suppressive milieu and enhances the activation of CD3^(+)T cells,providing potential solutions for enhancing immune-based cancer interventions. 展开更多
关键词 Intermittent fasting Ly6G^(low)myeloid-derived suppressor cell apoptosis Extramedullary hematopoiesis Colony stimulating factor Glucose metabolism restriction
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