As a leading cause for morbidity and mortality in young adults,traumatic brain injury(TBI),along with the poorly understood TBI-related seizures inducing their predispositions,pose a major health and socioeconomic p...As a leading cause for morbidity and mortality in young adults,traumatic brain injury(TBI),along with the poorly understood TBI-related seizures inducing their predispositions,pose a major health and socioeconomic problem in the world(Huang,2013).展开更多
To the Editor:Intraductal papillary neoplasm of the bile duct(IPNB)may occur in the setting of primary sclerosing cholangitis,choledochal cysts or hepatolithiasis[1].The entity may be a precursor of cancer or intrahep...To the Editor:Intraductal papillary neoplasm of the bile duct(IPNB)may occur in the setting of primary sclerosing cholangitis,choledochal cysts or hepatolithiasis[1].The entity may be a precursor of cancer or intrahepatic cholangiocarcinoma.Invasive carcinoma,tubular or mucinous adenocarcinoma is present in approximately 40%-80%of IPNBs[1–3].IPNB is frequently found in the resection margins of patients undergoing hepatectomy for cholangiocarcinoma[4].展开更多
Amyotrophic lateral sclerosis(ALS)is a lethal neurodegenerative disease characterized by neuromuscular junction(NMJ)disruption,motor neuron(MN)axon degeneration,and neuronal death.Unfortunately,there is currently no e...Amyotrophic lateral sclerosis(ALS)is a lethal neurodegenerative disease characterized by neuromuscular junction(NMJ)disruption,motor neuron(MN)axon degeneration,and neuronal death.Unfortunately,there is currently no effective treatment available for ALS and consequently,most patients die several years post diagnosis.The neurodegeneration that occurs in ALS is considered to be a non-cell autonomous process involving interactions between the motor neuron and its diverse extracellular microenvironments via an unknown mechanism.Distal Axonopathy is one of the early disease signs;however,the involvement and contribution of neighboring tissues and specifically,the muscle environment to the disease pathology remain controversial.Few works have concluded that muscles play a minor role or none at all in ALS pathology.展开更多
The electrochemical reduction of alkylaquabis (dimethylglyoximato)Cobalt(Ⅲ) in the absence and presence of β-Cyclodextrin (β-CD) was inveingated by means of cylic voltammetry. It was found that β-CD facilitates th...The electrochemical reduction of alkylaquabis (dimethylglyoximato)Cobalt(Ⅲ) in the absence and presence of β-Cyclodextrin (β-CD) was inveingated by means of cylic voltammetry. It was found that β-CD facilitates the cleavage of Co-C bond during the reduchon process.展开更多
New application center in South Africa facilitates travels to ChinaAfrica’s first Chinese Visa Application Service Center opened its doors in Johannesburg,South Africa,on March 17 after a whole year’s preparation.Th...New application center in South Africa facilitates travels to ChinaAfrica’s first Chinese Visa Application Service Center opened its doors in Johannesburg,South Africa,on March 17 after a whole year’s preparation.The 41st such service center,it is located in the upmarket Sandton City Office Tower building in the affluent northern suburbs,enjoying convenient transportation.Travelers to China,who previously needed to apply for a visa at the Chinese Embassy in Pretona or the Consulate General of China in Johannesburg, can now apply at the center, making the visa application process faster and more convenient. A senior visa officer at the Johannesburg consulate talked to ChinAfrica about the need for the center and how to apply there for a visa.展开更多
Rose has emerged as a model ornamental plant for studies of flower development, senescence, and morphology, as well as the metabolism of floral fragrances and colors.Virus-induced gene silencing(VIGS) has long been us...Rose has emerged as a model ornamental plant for studies of flower development, senescence, and morphology, as well as the metabolism of floral fragrances and colors.Virus-induced gene silencing(VIGS) has long been used in functional genomics studies of rose by vacuum infiltration of cuttings or seedlings with an Agrobacterium suspension carrying TRV-derived vectors. However, VIGS in rose flowers remains a challenge because of its low efficiency and long time to establish silencing. Here we present a novel and rapid VIGS method that can be used to analyze gene function in rose,called ‘graft-accelerated VIGS’, where axil ary sprouts are cut from the rose plant and vacuum infiltrated with Agrobacterium. The inoculated scions are then grafted back onto the plants to flower and silencing phenotypes can be observed within 5 weeks, post-infiltration. Using this new method, we successfully silenced expression of the RhDFR, RhA G, and RhNUDXin rose flowers, and affected their color, petal number, as well as fragrance, respectively. This grafting method will facilitate high-throughput functional analysis of genes in rose flowers. Importantly, it may also be applied to other woody species that are not currently amenable to VIGS by conventional leaf or plantlet/seedling infiltration methods.展开更多
With the support by the National Natural Science Foundation of China,the research team directed by Prof.Wang XiaoGang(王晓刚)at the Beijing Advanced Innovation Center for Big Data-Based Precision Medicine,Beihang Univ...With the support by the National Natural Science Foundation of China,the research team directed by Prof.Wang XiaoGang(王晓刚)at the Beijing Advanced Innovation Center for Big Data-Based Precision Medicine,Beihang University,recently reported that lncRNA regulates osteoblast activity and bone formation in mice by up-regulating the osteogenic transcription factor Osterix,which was published in Nature Metabolism(2019,1:485—496).展开更多
When benefiting other beneficiaries,cushion plants may reciprocally receive feedback effects.The feedback effects on different sex morphs,however,remains unclear.In this study,taking the gynodioecious Arenaria polytri...When benefiting other beneficiaries,cushion plants may reciprocally receive feedback effects.The feedback effects on different sex morphs,however,remains unclear.In this study,taking the gynodioecious Arenaria polytrichiodes as a model species,we aimed to assess the sex-specific facilitation intensity of cushion plant by measuring the beneficiary cover ratio,and to assess the potential costs in cushion reproductive functions by measuring the flower and fruit cover ratios.The total beneficiary cover ratio was similar between females and hermaphrodites.Females produced much less flowers but more fruits than hermaphrodites.These results suggested that females and hermaphrodites possess similar facilitation intensity,and female cushion A.polytrichoides may allocate more resources saved from pollen production to seed production,while hermaphrodites possibly allocate more resources to pollen production hence reducing seed production.The surface areas covered by beneficiaries produced less flowers and fruits than areas without beneficiaries.In addition,strong negative correlations between beneficiary cover and flower cover were detected for both females and hermaphrodites,but the correlation strength were similar for these two sex morphs.However,the correlation between beneficiary cover and fruit cover was only significantly negative for females,suggesting that beneficiary plants negatively affect fruit reproduction of females while have neutral effects on hermaphrodites.All the results suggest that to facilitate other beneficiaries can induce reproductive costs on cushion A.polytrichoides,with females possibly suffering greater cost than hermaphrodites.Such differentiation in reproductive costs between sex morphs,in long-term perspective,may imply sex imbalance in population dynamics.展开更多
Ongoing encroachment is driving recent alpine shrubline dynamics globally,but the role of shrub-shrub interactions in shaping shrublines and their relationships with stem density changes remain poorly understood.Here,...Ongoing encroachment is driving recent alpine shrubline dynamics globally,but the role of shrub-shrub interactions in shaping shrublines and their relationships with stem density changes remain poorly understood.Here,the size and age of shrubs from 26 Salix shrubline populations along a 900-km latitudinal gradient(30°-38°N)were measured and mapped across the eastern Tibetan Plateau.Point pattern analyses were used to quantify the spatial distribution patterns of juveniles and adults,and to assess spatial associations between them.Mean intensity of univariate and bivariate spatial patterns was related to biotic and abiotic variables.Bivariate mark correlation functions with a quantitative mark(shrub height,basal stem diameter,crown width)were also employed to investigate the spatial relationships between shrub traits of juveniles and adults.Structural equation models were used to explore the relationships among conspecific interactions,patterns,shrub traits and recruitment dynamics under climate change.Most shrublines showed clustered patterns,suggesting the existence of conspecific facilitation.Clustered patterns of juveniles and conspecific interactions(potentially facilitation)tended to intensify with increasing soil moisture stress.Summer warming before 2010 triggered positive effects on population interactions and spatial patterns via increased shrub recruitment.However,summer warming after2010 triggered negative effects on interactions through reduced shrub recruitment.Therefore,shrub recruitment shifts under rapid climate change could impact spatial patterns,alter conspecific interactions and modify the direction and degree of shrublines responses to climate.These changes would have profound implications for the stability of alpine woody ecosystems.展开更多
The challenge in the clinical treatment of Parkinson's disease lies in the lack of disease-modifying therapies that can halt or slow down the progression. Peptide drugs, such as exenatide (Exe), with potential dis...The challenge in the clinical treatment of Parkinson's disease lies in the lack of disease-modifying therapies that can halt or slow down the progression. Peptide drugs, such as exenatide (Exe), with potential disease-modifying efficacy, have difficulty in crossing the blood-brain barrier (BBB) due to their large molecular weight. Herein, we fabricate multi-functionalized lipid nanoparticles (LNP) Lpc-BoSA/CSO with BBB targeting, permeability-increasing and responsive release functions. Borneol is chemically bonded with stearic acid and, as one of the components of Lpc-BoSA/CSO, is used to increase BBB permeability. Immunofluorescence results of brain tissue of 15-month-old C57BL/6 mice show that Lpc-BoSA/CSO disperses across the BBB into brain parenchyma, and the amount is 4.21 times greater than that of conventional LNP. Motor symptoms of mice in Lpc-BoSA/CSO-Exe group are significantly improved, and the content of dopamine is 1.85 times (substantia nigra compacta) and 1.49 times (striatum) that of PD mice. α-Synuclein expression and Lewy bodies deposition are reduced to 51.85% and 44.72% of PD mice, respectively. Immunohistochemical mechanism studies show AKT expression in Lpc-BoSA/CSO-Exe is 4.23 times that of PD mice and GSK-3β expression is reduced to 18.41%. Lpc-BoSA/CSO-Exe could reduce the production of α-synuclein and Lewy bodies through AKT/GSK-3β pathway, and effectively prevent the progressive deterioration of Parkinson's disease. In summary, Lpc-BoSA/CSO-Exe increases the entry of exenatide into brain and promotes its clinical application for Parkinson's disease therapy.展开更多
With the rapid growth of the global digital economy, cross-border e-commerce, as an emerging form of trade, has gradually become a powerful engine to promote the development of global trade. BRICS is an important forc...With the rapid growth of the global digital economy, cross-border e-commerce, as an emerging form of trade, has gradually become a powerful engine to promote the development of global trade. BRICS is an important force in the global economy, and the progress of the BRICS countries' trade facilitation level has an important impact on the global trade environment. This paper conducts an in-depth study of the dynamic changes in BRICS trade facilitation from 2013 to 2022, and uses an extended gravity model to analyze the specific impact of this change on China's exports using cross-border e-commerce. The results show that although the BRICS countries have made some progress in trade facilitation, the overall level still needs to be improved, and there are obvious differences among member countries. However, the improvement of trade facilitation among BRICS countries has undoubtedly brought significant positive effects to China's exports using cross-border e-commerce.展开更多
Lawmakers call for stepping up hydrogen power production to facilitate China’s clean and low-carbon energy transformation and create a new engine of growth.
Supported catalysts based on metal nanoparticles are a class of widely used heterogeneous catalysts in industry.The catalytic performances of supported metal catalysts are highly determined by many parameters of metal...Supported catalysts based on metal nanoparticles are a class of widely used heterogeneous catalysts in industry.The catalytic performances of supported metal catalysts are highly determined by many parameters of metal nanoparticles such as their particle size,composition,surface structure and also interfacial interaction with supports[1].Supported metal catalysts are展开更多
目的分析整合式慢性病社区健康管理模式实施的促进和障碍因素,区分模式服务量高覆盖率组和低覆盖率组在实施性研究的整合性理论框架(consolidated framework for implementation research,CFIR)上的结构差异,为政府部门提供政策建议。...目的分析整合式慢性病社区健康管理模式实施的促进和障碍因素,区分模式服务量高覆盖率组和低覆盖率组在实施性研究的整合性理论框架(consolidated framework for implementation research,CFIR)上的结构差异,为政府部门提供政策建议。方法结合CFIR对22名专家进行半结构化访谈,采用定性结构评级法对13家社区卫生服务中心受访者评分,利用NVivo 12软件编码。结果高覆盖率组和低覆盖率组的相对优势、外部政策与激励、实施准备度、反思和评价、领导个人特质5个CFIR结构有差异。促进因素包括:测量数据更加精准,提高了高血压和糖尿病患者的异常检出率和控制率;模式实现了服务、技术、数据“三整合”,优化管理流程,提供管理抓手;基础性和个性化服务结合吸引患者到基层就诊;模式与我国政策背景,初级卫生保健工作和以患者为中心理念兼容;数字化工具的应用减轻医护人员工作负担;领导重视是基础,利益方间的通力合作是重要保障。障碍因素包括:宏观层面缺少卫生行政机构的支持性政策,组织架构和运行机制尚未建立,建设、投入主体以及具体工作规范和流程有待明确;缺乏监督管理机制和质量评估小组;模式推广目标模糊;缺乏规范化系统性的培训计划;为不同群体提供服务存在挑战,缺乏有效的社会面宣传;模式仍须提高需方获得感;社区布局限制了模式的服务提供。结论卫生行政部门应明确模式的建设、运行、投入主体,完善组织架构并明确各利益方的功能定位和职责分工,进一步制定工作规范和工作流程;建立信息反馈机制和质量控制小组并进行定期评估;制定清晰的目标;加大宣传教育,扩大宣传面;利用数字化工具形成良性医患互动机制。展开更多
Strongly-interacting Rydberg atomic ensembles have shown intense collective excitation effects due to the inclusion of single Rydberg excitation shared by multiple atoms in the ensemble.In this paper we investigate a ...Strongly-interacting Rydberg atomic ensembles have shown intense collective excitation effects due to the inclusion of single Rydberg excitation shared by multiple atoms in the ensemble.In this paper we investigate a counter-intuitive Rydberg excitation facilitation with a strongly-interacting atomic ensemble in the strong probe-field regime,which is enabled by the role of a control atom nearby.Differing from the case of a single ensemble,we show that,the control atom's excitation adds to a second two-photon transition onto the doubly-excited Rydberg state,arising an excitation facilitation for the ensemble atoms.Our numerical studies depending on the method of quantum Monte Carlo wave function,exhibit the observation constraints of this excitation facilitation effect under practical experimental conditions.The results obtained can provide a flexible control for the excitation of Rydberg atomic ensembles and participate further uses in developing mesoscopic Rydberg gates for multiqubit quantum computation.展开更多
Consider a generalized model of the facilitated exclusion process, which is a onedimensional exclusion process with a dynamical constraint that prevents the particle at site x from jumping to x+1 (or x-1) if the sites...Consider a generalized model of the facilitated exclusion process, which is a onedimensional exclusion process with a dynamical constraint that prevents the particle at site x from jumping to x+1 (or x-1) if the sites x-1, x-2 (or x+1, x+2) are empty. It is nongradient and lacks invariant measures of product form. The purpose of this paper is to identify the invariant measures and to show that they satisfy both exponential decay of correlations and equivalence of ensembles. These properties will play a pivotal role in deriving the hydrodynamic limit.展开更多
Objective:This study aimed to investigate the nurses’perspectives on open family visitation and its barriers and facilitators in neonatal intensive care units(NICUs).Methods:This is a descriptive,cross-sectional stud...Objective:This study aimed to investigate the nurses’perspectives on open family visitation and its barriers and facilitators in neonatal intensive care units(NICUs).Methods:This is a descriptive,cross-sectional study.A total of 113 nurses employed in 3 main NICUs of Tabriz participated in the study through the census sampling method.Nurses’perspectives on open visitation and its facilitators and barriers were assessed and analyzed using the Beliefs and Attitudes toward Visitation in NICU Questionnaire(BAVNIQ)and descriptive and analytical statistics,respectively.Results:Approximately 74%of the nurses who participating in the study had a moderate perspective on open visitation.From the nurses’viewpoint,“Parents’low awareness of sensitivity and hygienic principles of the NICU”was the first(90.3%)barrier,and the 2 factors,namely,“physical structure of the ward/lack of sufficient space”and“far distance between family’s residence and the hospital/having another child,”were the second(86.8%)barrier with an equal percentage.Among the facilitating factors,“Supporting employed parents during the neonate’s hospitalization”and“providing facilities for family accommodation in the hospital”were the first(82.3%)and the second(79.6%)facilitators,respectively,for open visitation.Conclusions:The majority of NICU nurses had a moderate perspective on the family open visitation.This reluctance seems to be originated mainly from the factors inhibiting open visitation,making its implementation challenging for nurses.The perspective of the frontline staff in caring for vulnerable infants on facilitators and barriers to open visitation may help policymakers,managers,and relevant officials in decision-making and implementing new visiting policies in the NICUs.展开更多
HIV counseling and testing(HCT)has become paramount in the prevention and control of HIV/AIDS worldwide.However,the uptake of HCT has been very slow globally,especially in sub-Saharan Africa.Student nurses formed the ...HIV counseling and testing(HCT)has become paramount in the prevention and control of HIV/AIDS worldwide.However,the uptake of HCT has been very slow globally,especially in sub-Saharan Africa.Student nurses formed the largest group undergoing health care training in the country compared to doctors and other health cadres.According to WHO,they are part of the most vulnerable group to HIV infection,judging by the fact that they interact more with patients/clients than other healthcare professionals.This study aimed to determine the prevalence of HCT uptake,knowledge,and attitude and evaluate influencing factors among student nurses and midwives in public nursing schools.An institutional-based cross-sectional study design was employed to collect data from 305 randomly selected nursing students and midwives using a validated and reliable self-administered questionnaire.Descriptive statistics(percentages,mean and standard deviation)and inferential statistics(chi square,logistics regression,one-way ANOVA and independent samples t-test)were used for data analysis using SPSS version 25.0.A p-value<0.05 was considered for statistical significance.Out of the 305 students recruited for the study,60.98%were females,with a mean age of 25.5 years old.About 58.4%of the participants had tested for HIV in the past.About 95.7%acknowledged the importance of HCT in the prevention and control of HIV/AIDS.HCT uptake among student nurses and midwives was influenced by factors ranging from an individual that are interpersonal challenges(such as concerns of friends),perceived susceptibility to the disease,lack of confidentiality,stigma and discrimination from health service providers.Therefore,these barriers can be addressed through an organized targeted health education intervention and advocacy programs across health training institutions in the Gambia and beyond.展开更多
文摘As a leading cause for morbidity and mortality in young adults,traumatic brain injury(TBI),along with the poorly understood TBI-related seizures inducing their predispositions,pose a major health and socioeconomic problem in the world(Huang,2013).
文摘To the Editor:Intraductal papillary neoplasm of the bile duct(IPNB)may occur in the setting of primary sclerosing cholangitis,choledochal cysts or hepatolithiasis[1].The entity may be a precursor of cancer or intrahepatic cholangiocarcinoma.Invasive carcinoma,tubular or mucinous adenocarcinoma is present in approximately 40%-80%of IPNBs[1–3].IPNB is frequently found in the resection margins of patients undergoing hepatectomy for cholangiocarcinoma[4].
基金supported by the Israel Science Foundation(grant number 561-11)the European Research Council(grant number 309377)to EP
文摘Amyotrophic lateral sclerosis(ALS)is a lethal neurodegenerative disease characterized by neuromuscular junction(NMJ)disruption,motor neuron(MN)axon degeneration,and neuronal death.Unfortunately,there is currently no effective treatment available for ALS and consequently,most patients die several years post diagnosis.The neurodegeneration that occurs in ALS is considered to be a non-cell autonomous process involving interactions between the motor neuron and its diverse extracellular microenvironments via an unknown mechanism.Distal Axonopathy is one of the early disease signs;however,the involvement and contribution of neighboring tissues and specifically,the muscle environment to the disease pathology remain controversial.Few works have concluded that muscles play a minor role or none at all in ALS pathology.
文摘The electrochemical reduction of alkylaquabis (dimethylglyoximato)Cobalt(Ⅲ) in the absence and presence of β-Cyclodextrin (β-CD) was inveingated by means of cylic voltammetry. It was found that β-CD facilitates the cleavage of Co-C bond during the reduchon process.
文摘New application center in South Africa facilitates travels to ChinaAfrica’s first Chinese Visa Application Service Center opened its doors in Johannesburg,South Africa,on March 17 after a whole year’s preparation.The 41st such service center,it is located in the upmarket Sandton City Office Tower building in the affluent northern suburbs,enjoying convenient transportation.Travelers to China,who previously needed to apply for a visa at the Chinese Embassy in Pretona or the Consulate General of China in Johannesburg, can now apply at the center, making the visa application process faster and more convenient. A senior visa officer at the Johannesburg consulate talked to ChinAfrica about the need for the center and how to apply there for a visa.
基金supported by the National Natural Science Foundation of China (31501791, 31660579, and 31360492)Leading talents in science and technology (2016HA005)funded in part by Beijing Natural Science Foundation (6162017)
文摘Rose has emerged as a model ornamental plant for studies of flower development, senescence, and morphology, as well as the metabolism of floral fragrances and colors.Virus-induced gene silencing(VIGS) has long been used in functional genomics studies of rose by vacuum infiltration of cuttings or seedlings with an Agrobacterium suspension carrying TRV-derived vectors. However, VIGS in rose flowers remains a challenge because of its low efficiency and long time to establish silencing. Here we present a novel and rapid VIGS method that can be used to analyze gene function in rose,called ‘graft-accelerated VIGS’, where axil ary sprouts are cut from the rose plant and vacuum infiltrated with Agrobacterium. The inoculated scions are then grafted back onto the plants to flower and silencing phenotypes can be observed within 5 weeks, post-infiltration. Using this new method, we successfully silenced expression of the RhDFR, RhA G, and RhNUDXin rose flowers, and affected their color, petal number, as well as fragrance, respectively. This grafting method will facilitate high-throughput functional analysis of genes in rose flowers. Importantly, it may also be applied to other woody species that are not currently amenable to VIGS by conventional leaf or plantlet/seedling infiltration methods.
文摘With the support by the National Natural Science Foundation of China,the research team directed by Prof.Wang XiaoGang(王晓刚)at the Beijing Advanced Innovation Center for Big Data-Based Precision Medicine,Beihang University,recently reported that lncRNA regulates osteoblast activity and bone formation in mice by up-regulating the osteogenic transcription factor Osterix,which was published in Nature Metabolism(2019,1:485—496).
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0502 to H.S.)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20050203 to H.S.)+3 种基金the Yunnan Applied Basic Research Project(202001AT070060 to J.G.C.)the National Natural Science Foundation of China(31271552 to J.G.C.)the CAS“Light of West China”Program(J.G.C.)the Young Academic and Technical Leader Raising Foundation of Yunnan Province(202205AC160053 to J.G.C.)。
文摘When benefiting other beneficiaries,cushion plants may reciprocally receive feedback effects.The feedback effects on different sex morphs,however,remains unclear.In this study,taking the gynodioecious Arenaria polytrichiodes as a model species,we aimed to assess the sex-specific facilitation intensity of cushion plant by measuring the beneficiary cover ratio,and to assess the potential costs in cushion reproductive functions by measuring the flower and fruit cover ratios.The total beneficiary cover ratio was similar between females and hermaphrodites.Females produced much less flowers but more fruits than hermaphrodites.These results suggested that females and hermaphrodites possess similar facilitation intensity,and female cushion A.polytrichoides may allocate more resources saved from pollen production to seed production,while hermaphrodites possibly allocate more resources to pollen production hence reducing seed production.The surface areas covered by beneficiaries produced less flowers and fruits than areas without beneficiaries.In addition,strong negative correlations between beneficiary cover and flower cover were detected for both females and hermaphrodites,but the correlation strength were similar for these two sex morphs.However,the correlation between beneficiary cover and fruit cover was only significantly negative for females,suggesting that beneficiary plants negatively affect fruit reproduction of females while have neutral effects on hermaphrodites.All the results suggest that to facilitate other beneficiaries can induce reproductive costs on cushion A.polytrichoides,with females possibly suffering greater cost than hermaphrodites.Such differentiation in reproductive costs between sex morphs,in long-term perspective,may imply sex imbalance in population dynamics.
基金the National Natural Science Foundation of China(42271054)the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0301)。
文摘Ongoing encroachment is driving recent alpine shrubline dynamics globally,but the role of shrub-shrub interactions in shaping shrublines and their relationships with stem density changes remain poorly understood.Here,the size and age of shrubs from 26 Salix shrubline populations along a 900-km latitudinal gradient(30°-38°N)were measured and mapped across the eastern Tibetan Plateau.Point pattern analyses were used to quantify the spatial distribution patterns of juveniles and adults,and to assess spatial associations between them.Mean intensity of univariate and bivariate spatial patterns was related to biotic and abiotic variables.Bivariate mark correlation functions with a quantitative mark(shrub height,basal stem diameter,crown width)were also employed to investigate the spatial relationships between shrub traits of juveniles and adults.Structural equation models were used to explore the relationships among conspecific interactions,patterns,shrub traits and recruitment dynamics under climate change.Most shrublines showed clustered patterns,suggesting the existence of conspecific facilitation.Clustered patterns of juveniles and conspecific interactions(potentially facilitation)tended to intensify with increasing soil moisture stress.Summer warming before 2010 triggered positive effects on population interactions and spatial patterns via increased shrub recruitment.However,summer warming after2010 triggered negative effects on interactions through reduced shrub recruitment.Therefore,shrub recruitment shifts under rapid climate change could impact spatial patterns,alter conspecific interactions and modify the direction and degree of shrublines responses to climate.These changes would have profound implications for the stability of alpine woody ecosystems.
基金National Natural Science Foundation of China(grant nos.81973267)Natural Science Foundation of Zhejiang Province(grant nos.LD19H300001).
文摘The challenge in the clinical treatment of Parkinson's disease lies in the lack of disease-modifying therapies that can halt or slow down the progression. Peptide drugs, such as exenatide (Exe), with potential disease-modifying efficacy, have difficulty in crossing the blood-brain barrier (BBB) due to their large molecular weight. Herein, we fabricate multi-functionalized lipid nanoparticles (LNP) Lpc-BoSA/CSO with BBB targeting, permeability-increasing and responsive release functions. Borneol is chemically bonded with stearic acid and, as one of the components of Lpc-BoSA/CSO, is used to increase BBB permeability. Immunofluorescence results of brain tissue of 15-month-old C57BL/6 mice show that Lpc-BoSA/CSO disperses across the BBB into brain parenchyma, and the amount is 4.21 times greater than that of conventional LNP. Motor symptoms of mice in Lpc-BoSA/CSO-Exe group are significantly improved, and the content of dopamine is 1.85 times (substantia nigra compacta) and 1.49 times (striatum) that of PD mice. α-Synuclein expression and Lewy bodies deposition are reduced to 51.85% and 44.72% of PD mice, respectively. Immunohistochemical mechanism studies show AKT expression in Lpc-BoSA/CSO-Exe is 4.23 times that of PD mice and GSK-3β expression is reduced to 18.41%. Lpc-BoSA/CSO-Exe could reduce the production of α-synuclein and Lewy bodies through AKT/GSK-3β pathway, and effectively prevent the progressive deterioration of Parkinson's disease. In summary, Lpc-BoSA/CSO-Exe increases the entry of exenatide into brain and promotes its clinical application for Parkinson's disease therapy.
基金Supported by Western Project of National Social Science Fund of China(23XJY013)Project of Social Science Foundation of Shaanxi Province(2022D032).
文摘With the rapid growth of the global digital economy, cross-border e-commerce, as an emerging form of trade, has gradually become a powerful engine to promote the development of global trade. BRICS is an important force in the global economy, and the progress of the BRICS countries' trade facilitation level has an important impact on the global trade environment. This paper conducts an in-depth study of the dynamic changes in BRICS trade facilitation from 2013 to 2022, and uses an extended gravity model to analyze the specific impact of this change on China's exports using cross-border e-commerce. The results show that although the BRICS countries have made some progress in trade facilitation, the overall level still needs to be improved, and there are obvious differences among member countries. However, the improvement of trade facilitation among BRICS countries has undoubtedly brought significant positive effects to China's exports using cross-border e-commerce.
文摘Lawmakers call for stepping up hydrogen power production to facilitate China’s clean and low-carbon energy transformation and create a new engine of growth.
文摘Supported catalysts based on metal nanoparticles are a class of widely used heterogeneous catalysts in industry.The catalytic performances of supported metal catalysts are highly determined by many parameters of metal nanoparticles such as their particle size,composition,surface structure and also interfacial interaction with supports[1].Supported metal catalysts are
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12174106 and 11474094)the Science and Technology Commission of Shanghai Municipality(Grant No.18ZR1412800)。
文摘Strongly-interacting Rydberg atomic ensembles have shown intense collective excitation effects due to the inclusion of single Rydberg excitation shared by multiple atoms in the ensemble.In this paper we investigate a counter-intuitive Rydberg excitation facilitation with a strongly-interacting atomic ensemble in the strong probe-field regime,which is enabled by the role of a control atom nearby.Differing from the case of a single ensemble,we show that,the control atom's excitation adds to a second two-photon transition onto the doubly-excited Rydberg state,arising an excitation facilitation for the ensemble atoms.Our numerical studies depending on the method of quantum Monte Carlo wave function,exhibit the observation constraints of this excitation facilitation effect under practical experimental conditions.The results obtained can provide a flexible control for the excitation of Rydberg atomic ensembles and participate further uses in developing mesoscopic Rydberg gates for multiqubit quantum computation.
基金Supported in part by the National Natural Science Foundation of China(11731012, 11871425, 12271475)Fundamental Research Funds for Central Universities grant(2020XZZX002-03)。
文摘Consider a generalized model of the facilitated exclusion process, which is a onedimensional exclusion process with a dynamical constraint that prevents the particle at site x from jumping to x+1 (or x-1) if the sites x-1, x-2 (or x+1, x+2) are empty. It is nongradient and lacks invariant measures of product form. The purpose of this paper is to identify the invariant measures and to show that they satisfy both exponential decay of correlations and equivalence of ensembles. These properties will play a pivotal role in deriving the hydrodynamic limit.
基金supported by Pediatric Health Research Center,Tabriz University of Medical Sciences(Grant number:IR.TBZMED.REC.1398.585).
文摘Objective:This study aimed to investigate the nurses’perspectives on open family visitation and its barriers and facilitators in neonatal intensive care units(NICUs).Methods:This is a descriptive,cross-sectional study.A total of 113 nurses employed in 3 main NICUs of Tabriz participated in the study through the census sampling method.Nurses’perspectives on open visitation and its facilitators and barriers were assessed and analyzed using the Beliefs and Attitudes toward Visitation in NICU Questionnaire(BAVNIQ)and descriptive and analytical statistics,respectively.Results:Approximately 74%of the nurses who participating in the study had a moderate perspective on open visitation.From the nurses’viewpoint,“Parents’low awareness of sensitivity and hygienic principles of the NICU”was the first(90.3%)barrier,and the 2 factors,namely,“physical structure of the ward/lack of sufficient space”and“far distance between family’s residence and the hospital/having another child,”were the second(86.8%)barrier with an equal percentage.Among the facilitating factors,“Supporting employed parents during the neonate’s hospitalization”and“providing facilities for family accommodation in the hospital”were the first(82.3%)and the second(79.6%)facilitators,respectively,for open visitation.Conclusions:The majority of NICU nurses had a moderate perspective on the family open visitation.This reluctance seems to be originated mainly from the factors inhibiting open visitation,making its implementation challenging for nurses.The perspective of the frontline staff in caring for vulnerable infants on facilitators and barriers to open visitation may help policymakers,managers,and relevant officials in decision-making and implementing new visiting policies in the NICUs.
文摘HIV counseling and testing(HCT)has become paramount in the prevention and control of HIV/AIDS worldwide.However,the uptake of HCT has been very slow globally,especially in sub-Saharan Africa.Student nurses formed the largest group undergoing health care training in the country compared to doctors and other health cadres.According to WHO,they are part of the most vulnerable group to HIV infection,judging by the fact that they interact more with patients/clients than other healthcare professionals.This study aimed to determine the prevalence of HCT uptake,knowledge,and attitude and evaluate influencing factors among student nurses and midwives in public nursing schools.An institutional-based cross-sectional study design was employed to collect data from 305 randomly selected nursing students and midwives using a validated and reliable self-administered questionnaire.Descriptive statistics(percentages,mean and standard deviation)and inferential statistics(chi square,logistics regression,one-way ANOVA and independent samples t-test)were used for data analysis using SPSS version 25.0.A p-value<0.05 was considered for statistical significance.Out of the 305 students recruited for the study,60.98%were females,with a mean age of 25.5 years old.About 58.4%of the participants had tested for HIV in the past.About 95.7%acknowledged the importance of HCT in the prevention and control of HIV/AIDS.HCT uptake among student nurses and midwives was influenced by factors ranging from an individual that are interpersonal challenges(such as concerns of friends),perceived susceptibility to the disease,lack of confidentiality,stigma and discrimination from health service providers.Therefore,these barriers can be addressed through an organized targeted health education intervention and advocacy programs across health training institutions in the Gambia and beyond.