Objective:To explore the relationships among ambient temperature,ischemic stroke severity,and blood pressure.Methods:Meteorological data(2005–2015)were collected from the Guangzhou Meteorological Data Service.Ischemi...Objective:To explore the relationships among ambient temperature,ischemic stroke severity,and blood pressure.Methods:Meteorological data(2005–2015)were collected from the Guangzhou Meteorological Data Service.Ischemic stroke patients from the Department of Neurology of the First Affiliated Hospital,Sun Yat-sen University were retrospectively evaluated,each winter from 2005 to 2015.Patient demographics,baseline measurements,and National Institute of Health Stroke Scale(NIHSS)score were evaluated.Results:Three hundred sixty-two patients were included.The median latency from symptom onset to admission was 2 d(IQR:1–3 d).During recruitment,the highest and lowest temperatures were 39℃and 1.3℃,respectively.Hypertension was the most common comorbidity(75.1%).NIHSS scores at admission and discharge were higher in the cold-exposed group than in the controls regardless of the average temperature at admission.In addition,systolic and diastolic blood pressure values at admission were higher in the cold-exposed group than in the controls.When stratified by hypertensive status,the average and minimum temperatures at admission were negatively associated with systolic and diastolic blood pressure values in hypertensive patients.Reductions in the average and minimum temperatures at symptom onset were associated with more severe stroke.Conclusion:Ischemic stroke patients with symptom onset in winter had higher systolic blood pressure values and more serious neurologic deficits upon admission.展开更多
We employ novel digital Fresnel reflection holography to capture the 3D flows within the viscous sublayerof a smooth-wall turbulent channel flow at Reτ=400.The measurements reveal unsteady and diverse flow patterns i...We employ novel digital Fresnel reflection holography to capture the 3D flows within the viscous sublayerof a smooth-wall turbulent channel flow at Reτ=400.The measurements reveal unsteady and diverse flow patterns in the sublayer including nearly uniform high and low speed flows and strong small-scale(onthe order of viscous wall units)spanwise meandering motions.The probability density functions(PDFs)ofwall shear stresses show a clear discrepancy in high stress range with those from direct numerical simu-lation(DNS),which is attributed to the unresolved streamwise and spanwise motions by DNS.Moreover,the PDF of Lagrangian particle accelerations yields a stretched exponential shape like that in homogenousisotropic turbulence,indicating strong intermittency in the sublayer.We find a significant fraction of highaccelerations is associated with the small-scale meandering motions.Our study helps explain the effectof sublayer-scale roughness on reducing drag and flow separation reported in the literature.展开更多
The G-quadruplex(G4)sequences are short fragments of 4-i nterval triple guanine(G)with frequent and ubiquitous distribution in the genome and RNA transcripts.The G4sequences are usually folded into secondary“knot”st...The G-quadruplex(G4)sequences are short fragments of 4-i nterval triple guanine(G)with frequent and ubiquitous distribution in the genome and RNA transcripts.The G4sequences are usually folded into secondary“knot”structure via Hoogsteen hydrogen bond to exert negative regulation on a variety of biological processes,including DNA replication and transcription,mRNA translation,and telomere maintenance.Recent structural biological and mouse genetics studies have demonstrated that RHAU(DHX36)can bind and unwind the G4“knots”to modulate embryonic development and postnatal organ function.Deficiency of RHAU gives rise to embryonic lethality,impaired organogenesis,and organ dysfunction.These studies uncovered the pivotal G4 resolvase function of RHAU to release the G4 barrier,which plays fundamental roles in development and physiological homeostasis.This review discusses the latest advancements and findings in deciphering RHAU functions using animal models.展开更多
In order to extract solanesol from potato stems and leaves more effectively and improve the extraction rate of solanesol, the same batch of potato stems and leaves harvested from Guyuan, Ningxia was selected as a rese...In order to extract solanesol from potato stems and leaves more effectively and improve the extraction rate of solanesol, the same batch of potato stems and leaves harvested from Guyuan, Ningxia was selected as a research object, cell wall of potato stems and leaves was broken by enzymolysis with cellulase and high- speed shearing, and then reflux-extracted with 95% ethanol. Solanesol content was determined by HPLC, and extract yield was calculated. Extract yield and solanesol extraction rate was used as an index for comparison of difference between the 2 wall-breaking methods, so as to select the optimal wall-breaking method. The results showed that enzymolysis with cellulase exhibited extraction rate and extract yield of solanesol of 91.38% and 8.02%, respectively, which were better than those under high-speed shear emulsification technique. The enzymolysis wall-breaking method has the advantages of simple operation and strong feasibility.展开更多
Due to the increase in English as a lingua franca,the Chinese government and educators are preoccupied with the demand to develop greater numbers of people who can communicate accurately and competently in English.Eng...Due to the increase in English as a lingua franca,the Chinese government and educators are preoccupied with the demand to develop greater numbers of people who can communicate accurately and competently in English.English stories are generally not used by language teachers and are considered unsuitable in China,further,teachers fail to explain stories’content and apply traditional teaching approaches in the class.展开更多
Although China has established more than 600 wetland nature reserves, conservation gaps still exist for many species, especially for freshwater fishes. Underlying this problem is the fact that top-level planning is mi...Although China has established more than 600 wetland nature reserves, conservation gaps still exist for many species, especially for freshwater fishes. Underlying this problem is the fact that top-level planning is missing in the construction of nature reserves. To promote the development of nature reserves for fishes, this study took the middle and lower reaches of the Yangtze River basin(MLYRB) as an example to carry out top-level reserve network planning for fishes using approaches of systematic conservation planning. Typical fish species living in freshwater habitats were defined and considered in the planning. Based on sample data collected from large quantities of literatures, continuous distribution patterns of 142 fishes were obtained with species distribution modeling and subsequent processing, and the distributions of another eleven species were artificially designated. With the distribution pattern of species, Marxan was used to carry out conservation planning. To obtain ideal solutions with representativeness, persistence, and efficiency, parameters were set with careful consideration regarding existing wetland reserves, human disturbances, hydrological connectivity, and representation targets of species. Marxan produced the selection frequency of planning units(PUs) and a best solution. Selection frequency indicates the relative protection importance of a PU. The best solution is a representative of ideal fish reserve networks. Both of the PUs with high selection frequency and those in the best solution have low proportions included in existing wetland nature reserves, suggesting that there are significant conservation gaps for fish species in MLYRB. The best solution could serve as a reference for establishing a fish reserve network in the MLYRB. There is great flexibility for replacing selected PUs in the solution, and such flexibility facilitates the implementation of the solution in reality in case of unexpected obstacles. Further, we suggested adopting a freshwater management framework in the implementation of such solution.展开更多
Systematic conservation planning(SCP)is a widely accepted biodiversity-focused approach to selecting priority areas for protection.Since freshwater ecosystems are globally in urgent need of more conservation and the d...Systematic conservation planning(SCP)is a widely accepted biodiversity-focused approach to selecting priority areas for protection.Since freshwater ecosystems are globally in urgent need of more conservation and the development of freshwater protected areas has lagged behind such need,SCP is proposed to be widely applied in freshwater conservation.As SCP originates from terrestrial realms,freshwater-specific characteristics should be considered when applied to freshwater systems.The challenges mainly include difficulty in data collection for freshwater species and uncertainty in classification of coarse-filters for representation,while also considering the maintenance of natural connectivity in fresh waters and taking longitudinal,lateral,and climate-change-caused threats into account.Only by addressing these issues may the representativeness and persistence of freshwater biodiversity be ensured in the proposed conservation network.Though challenging at times,the application of systematic approaches in freshwater conservation planning has been widely attempted throughout the last 12 years and applied in different freshwater ecosystems at different scales.In addition,the consideration of freshwater-specific issues has been becoming more and more comprehensive.This review divides the whole process of SCP into successive steps while discussing detailed applications of freshwater planning at each step.First,according to the review,each step attempts to explore many alternatives,such as usingsurrogates from the species level to the ecosystem level(or a combination within this range)to represent the spatial variation of freshwater biodiversity,deriving raw data from various sources to use for planning,applying different techniques to expand or integrate data,setting various target forms to ensure representativeness or persistence,considering existing protected areas in different ways in the process of planning,using priority principles in various paradigms for both representativeness and persistence,and applying several types of software to the final design of the protection network.Second,applications in each step(except‘‘setting representative targets’’)have been more or less tried in considering freshwater-specific issues.For representativeness issues,accepting various sources of information and attempting different ways of data reduction are the main approaches to solving these challenges.For persistence issues,identifying the main ecological processes and threats in freshwater systems and involving them in the process of prioritization are major concerns,and setting targets or priority principles are key steps for taking these persistence issues into account.Finally,more systematic conservation of freshwater systems and new or improved alternatives of each step are expected to enrich this field of study.展开更多
Dear Editor,Tetralogy of Fallot(TOF)is the most common complex congenital heart disease.Besides gene mutations and copy number variants,altered protein function induced by posttranscriptional or translational regulati...Dear Editor,Tetralogy of Fallot(TOF)is the most common complex congenital heart disease.Besides gene mutations and copy number variants,altered protein function induced by posttranscriptional or translational regulation also contributes to the onset of TOF.1 MiRNAs are short noncoding RNAs that bind to the 3’-UTR of target mRNAs to repress protein production.However,the causal link between miRNAs and TOF and the underlying mechanism has not been established.展开更多
2022年11月11日至2023年6月30日,在萨凡纳时尚电影博物馆(SCADFASH)的展览"悬垂的艺术"(The Art of Draping)中,首次展出了来自阿瑟丁·阿拉亚(Azzedine Alaia)收藏的格雷斯夫人(Madame Gres)的服装作品。作品横跨1930年...2022年11月11日至2023年6月30日,在萨凡纳时尚电影博物馆(SCADFASH)的展览"悬垂的艺术"(The Art of Draping)中,首次展出了来自阿瑟丁·阿拉亚(Azzedine Alaia)收藏的格雷斯夫人(Madame Gres)的服装作品。作品横跨1930年代到1970年代,其标志性的古典悬垂褶皱设计,为女性的身体雕刻出一种纯净的魅惑力。展开更多
文摘Objective:To explore the relationships among ambient temperature,ischemic stroke severity,and blood pressure.Methods:Meteorological data(2005–2015)were collected from the Guangzhou Meteorological Data Service.Ischemic stroke patients from the Department of Neurology of the First Affiliated Hospital,Sun Yat-sen University were retrospectively evaluated,each winter from 2005 to 2015.Patient demographics,baseline measurements,and National Institute of Health Stroke Scale(NIHSS)score were evaluated.Results:Three hundred sixty-two patients were included.The median latency from symptom onset to admission was 2 d(IQR:1–3 d).During recruitment,the highest and lowest temperatures were 39℃and 1.3℃,respectively.Hypertension was the most common comorbidity(75.1%).NIHSS scores at admission and discharge were higher in the cold-exposed group than in the controls regardless of the average temperature at admission.In addition,systolic and diastolic blood pressure values at admission were higher in the cold-exposed group than in the controls.When stratified by hypertensive status,the average and minimum temperatures at admission were negatively associated with systolic and diastolic blood pressure values in hypertensive patients.Reductions in the average and minimum temperatures at symptom onset were associated with more severe stroke.Conclusion:Ischemic stroke patients with symptom onset in winter had higher systolic blood pressure values and more serious neurologic deficits upon admission.
文摘We employ novel digital Fresnel reflection holography to capture the 3D flows within the viscous sublayerof a smooth-wall turbulent channel flow at Reτ=400.The measurements reveal unsteady and diverse flow patterns in the sublayer including nearly uniform high and low speed flows and strong small-scale(onthe order of viscous wall units)spanwise meandering motions.The probability density functions(PDFs)ofwall shear stresses show a clear discrepancy in high stress range with those from direct numerical simu-lation(DNS),which is attributed to the unresolved streamwise and spanwise motions by DNS.Moreover,the PDF of Lagrangian particle accelerations yields a stretched exponential shape like that in homogenousisotropic turbulence,indicating strong intermittency in the sublayer.We find a significant fraction of highaccelerations is associated with the small-scale meandering motions.Our study helps explain the effectof sublayer-scale roughness on reducing drag and flow separation reported in the literature.
基金National Key Research and Development Program of ChinaGrant/Award Number:2019YFA0801601+1 种基金National Natural Science Foundation of ChinaGrant/Award Number:31930029,91854111 and 31571490。
文摘The G-quadruplex(G4)sequences are short fragments of 4-i nterval triple guanine(G)with frequent and ubiquitous distribution in the genome and RNA transcripts.The G4sequences are usually folded into secondary“knot”structure via Hoogsteen hydrogen bond to exert negative regulation on a variety of biological processes,including DNA replication and transcription,mRNA translation,and telomere maintenance.Recent structural biological and mouse genetics studies have demonstrated that RHAU(DHX36)can bind and unwind the G4“knots”to modulate embryonic development and postnatal organ function.Deficiency of RHAU gives rise to embryonic lethality,impaired organogenesis,and organ dysfunction.These studies uncovered the pivotal G4 resolvase function of RHAU to release the G4 barrier,which plays fundamental roles in development and physiological homeostasis.This review discusses the latest advancements and findings in deciphering RHAU functions using animal models.
基金Supported by Ningxia Agricultural Comprehensive Development Demonstration Project of Integration of Potato Green High-yielding and Mechanized Operation Techniques in 2015(NTKJ2016-09-03)
文摘In order to extract solanesol from potato stems and leaves more effectively and improve the extraction rate of solanesol, the same batch of potato stems and leaves harvested from Guyuan, Ningxia was selected as a research object, cell wall of potato stems and leaves was broken by enzymolysis with cellulase and high- speed shearing, and then reflux-extracted with 95% ethanol. Solanesol content was determined by HPLC, and extract yield was calculated. Extract yield and solanesol extraction rate was used as an index for comparison of difference between the 2 wall-breaking methods, so as to select the optimal wall-breaking method. The results showed that enzymolysis with cellulase exhibited extraction rate and extract yield of solanesol of 91.38% and 8.02%, respectively, which were better than those under high-speed shear emulsification technique. The enzymolysis wall-breaking method has the advantages of simple operation and strong feasibility.
文摘Due to the increase in English as a lingua franca,the Chinese government and educators are preoccupied with the demand to develop greater numbers of people who can communicate accurately and competently in English.English stories are generally not used by language teachers and are considered unsuitable in China,further,teachers fail to explain stories’content and apply traditional teaching approaches in the class.
基金supported by fund of State Forestry Administration of China-United Nations Development Program/Global Environment Facility(83911 NP-2014-007)
文摘Although China has established more than 600 wetland nature reserves, conservation gaps still exist for many species, especially for freshwater fishes. Underlying this problem is the fact that top-level planning is missing in the construction of nature reserves. To promote the development of nature reserves for fishes, this study took the middle and lower reaches of the Yangtze River basin(MLYRB) as an example to carry out top-level reserve network planning for fishes using approaches of systematic conservation planning. Typical fish species living in freshwater habitats were defined and considered in the planning. Based on sample data collected from large quantities of literatures, continuous distribution patterns of 142 fishes were obtained with species distribution modeling and subsequent processing, and the distributions of another eleven species were artificially designated. With the distribution pattern of species, Marxan was used to carry out conservation planning. To obtain ideal solutions with representativeness, persistence, and efficiency, parameters were set with careful consideration regarding existing wetland reserves, human disturbances, hydrological connectivity, and representation targets of species. Marxan produced the selection frequency of planning units(PUs) and a best solution. Selection frequency indicates the relative protection importance of a PU. The best solution is a representative of ideal fish reserve networks. Both of the PUs with high selection frequency and those in the best solution have low proportions included in existing wetland nature reserves, suggesting that there are significant conservation gaps for fish species in MLYRB. The best solution could serve as a reference for establishing a fish reserve network in the MLYRB. There is great flexibility for replacing selected PUs in the solution, and such flexibility facilitates the implementation of the solution in reality in case of unexpected obstacles. Further, we suggested adopting a freshwater management framework in the implementation of such solution.
文摘Systematic conservation planning(SCP)is a widely accepted biodiversity-focused approach to selecting priority areas for protection.Since freshwater ecosystems are globally in urgent need of more conservation and the development of freshwater protected areas has lagged behind such need,SCP is proposed to be widely applied in freshwater conservation.As SCP originates from terrestrial realms,freshwater-specific characteristics should be considered when applied to freshwater systems.The challenges mainly include difficulty in data collection for freshwater species and uncertainty in classification of coarse-filters for representation,while also considering the maintenance of natural connectivity in fresh waters and taking longitudinal,lateral,and climate-change-caused threats into account.Only by addressing these issues may the representativeness and persistence of freshwater biodiversity be ensured in the proposed conservation network.Though challenging at times,the application of systematic approaches in freshwater conservation planning has been widely attempted throughout the last 12 years and applied in different freshwater ecosystems at different scales.In addition,the consideration of freshwater-specific issues has been becoming more and more comprehensive.This review divides the whole process of SCP into successive steps while discussing detailed applications of freshwater planning at each step.First,according to the review,each step attempts to explore many alternatives,such as usingsurrogates from the species level to the ecosystem level(or a combination within this range)to represent the spatial variation of freshwater biodiversity,deriving raw data from various sources to use for planning,applying different techniques to expand or integrate data,setting various target forms to ensure representativeness or persistence,considering existing protected areas in different ways in the process of planning,using priority principles in various paradigms for both representativeness and persistence,and applying several types of software to the final design of the protection network.Second,applications in each step(except‘‘setting representative targets’’)have been more or less tried in considering freshwater-specific issues.For representativeness issues,accepting various sources of information and attempting different ways of data reduction are the main approaches to solving these challenges.For persistence issues,identifying the main ecological processes and threats in freshwater systems and involving them in the process of prioritization are major concerns,and setting targets or priority principles are key steps for taking these persistence issues into account.Finally,more systematic conservation of freshwater systems and new or improved alternatives of each step are expected to enrich this field of study.
基金supported by grants from the National Key R&D Program of China(2021YFC2701101,H.W.)the National Natural Science Foundation of China(81930036 and 82150008,H.W.)the Commission for Science and Technology of Shanghai Municipality(20JC1418500,H.W.).
文摘Dear Editor,Tetralogy of Fallot(TOF)is the most common complex congenital heart disease.Besides gene mutations and copy number variants,altered protein function induced by posttranscriptional or translational regulation also contributes to the onset of TOF.1 MiRNAs are short noncoding RNAs that bind to the 3’-UTR of target mRNAs to repress protein production.However,the causal link between miRNAs and TOF and the underlying mechanism has not been established.
文摘2022年11月11日至2023年6月30日,在萨凡纳时尚电影博物馆(SCADFASH)的展览"悬垂的艺术"(The Art of Draping)中,首次展出了来自阿瑟丁·阿拉亚(Azzedine Alaia)收藏的格雷斯夫人(Madame Gres)的服装作品。作品横跨1930年代到1970年代,其标志性的古典悬垂褶皱设计,为女性的身体雕刻出一种纯净的魅惑力。
