The design thinking approach transforms student’s learning process to connect with real-world experience, making connections between knowledge and improving critical thinking and problem-solving capability. Previous ...The design thinking approach transforms student’s learning process to connect with real-world experience, making connections between knowledge and improving critical thinking and problem-solving capability. Previous research has focused on what design thinking is taught (content) and how it is taught (learning modes and assessment). However, there needs to be an integrative approach in the context of ecotourism education. Therefore, applying Wrigley and Straker’s Educational Design Ladder mode, this study develops an Ecotourism Design Thinking Curriculum framework to combine the ecotourism content, teaching/learning mode and assessment.展开更多
Objective:To investigate the prevalence of metabolically healthy obesity(MHO)and its relationship with incidence of metabolic syndrome(MetS),type 2diabetes mellitus(T2DM)and hypertension in individuals in the city of ...Objective:To investigate the prevalence of metabolically healthy obesity(MHO)and its relationship with incidence of metabolic syndrome(MetS),type 2diabetes mellitus(T2DM)and hypertension in individuals in the city of Yulin.Methods:We studied 1,666 participants,aged over18years at baseline,with free of components of the MetS except waist criteria.Participants were divided into three groups based on body mass index(Ibm):lean/normal weight(Ibm<23kg/m2),overweight(Ibm,23-24.9kg/m2),obesity(Ibm≥25 kg/m2).The cumulative incidence of MetS,T2DM and hypertension over 5.21years among groups was assessed.Results:The prevalence of MHO was 19.5%in the baseline population.During an average 5.21year follow-up,the cumulative incidence of MetS,T2DM and hypertension in1,666participants were 16.4%,19.1%and 3.9%,respectively.The obesity group had a significantly higher cumulative incidence of MetS(16.4%vs.3.2%,P<0.001),hypertension(19.1%vs.3.7%,P<0.001),and T2DM(3.9%vs.1.6%,P<0.001)compared to the lean/normal weight group.Each kg/m2 of Ibm carried increased risk for T2DM(19%),hypertension(11%)and MetS(13%).Conclusion:Metabolically healthy obesity individuals confer increased risk for hypertension,T2DM and the MetS than their non-obese counterparts.展开更多
Objective: Recent reports suggest that Cepharanthine(CEP),a natural alkaloid extracted from the roots of Stephania Cepharanthine Hayata,can inhibit the proliferation of various cancer cells,but few studies focus on it...Objective: Recent reports suggest that Cepharanthine(CEP),a natural alkaloid extracted from the roots of Stephania Cepharanthine Hayata,can inhibit the proliferation of various cancer cells,but few studies focus on its radiosensitization in nasopharyngeal carcinoma(NPC)cells. The aim of this study was to explore the radiosensitization effect and the potential mechanisms of CEP on nasopharyngeal carcinoma cell lines CNE-1 and CNE-2. Methods: The NPC cell lines CNE-1 and CNE-2 were treated with CEP(IC50)for 48 h before irration(IR);clonogenic survival was then assessed. The apoptosis and cell cycle progression were using flow cytometry.The DNA damage repair and cycle-regulating proteins were evaluated by Western blot analysis. Results: CEP could inhibit cell growth in both cell lines. The combination of CEP and radiation promote cell cycle G2/M phase arrest and apoptosis in CNE-1 and CNE-2 cells.DNA damage repair analysis showed that CEP has an inhibitory effect on DNA repair of CNE-1 and CNE-2 cells after radiation.Conclusion: CEP enhances tumor radioresponse through multiple mechanisms that may involve the halted cell cycle progression at G2/M phase and the inhibition of DNA repair after exposure to radiation.展开更多
ZrCoSb-based half-Heusler(HH)compounds are among the most promising thermoelectric(TE)materials for high-temperature power generation.Oxidation resistance is one of the key issues for realizing the practical applicati...ZrCoSb-based half-Heusler(HH)compounds are among the most promising thermoelectric(TE)materials for high-temperature power generation.Oxidation resistance is one of the key issues for realizing the practical application of TE materials for long-term service in the ambient working environment.In this work,the oxidation behavior of Zr_(0.5)Hf_(0.5)CoSb_(0.8)Sn_(0.2)(ZHCSS)half-Heusler is systematically studied in the service temperature range from 873 to 1073 K.It is revealed that three typical layers of oxidation products tend to form on the surface of HH sample,namely,the dense oxide layer(DOL)composed of(Zr,Hf)O_(2) and CoSb,the alternate oxide layer(AOL)composed of repeated(Zr,Hf)O_(2) and CoSb_(2)O_(6)/Co_(3)O_(4),and the CoSb layer between the DOL and AOL.The mass gain during oxidation is mainly caused by the rapid growth of AOL,which is controlled by the outward diffusion of Zr/Hf and the inward diffusion of oxygen.The formation of a continuous CoSb layer and DOL is found beneficial to block the outward diffusion of Zr/Hf.Based on the analysis of the dominant factors on the outward and inward diffusions as well as the reaction activation energy,a simple approach is proposed to improve the oxidation resistance of Zr_(0.5)Hf_(0.5)CoSb_(0.8)Sn_(0.2)by pre-oxidizing the sample in low oxygen pressure to form the dense(Zr,Hf)O_(2) and CoSb layers as oxidation protecting and/or diffusion blocking layers.The oxidation test shows the effectiveness of such pre-oxidation on the formation and growth of the AOL and therefore on improving the service stability of Zr_(0.5)Hf_(0.5)CoSb_(0.8)Sn_(0.2)at high temperatures in the air.展开更多
A broad tunability of the thermoelectric and mechanical properties of CoSb_(3) has been demonstrated by adjusting the composition with the addition of an increasing number of elements.However,such a strategy may negat...A broad tunability of the thermoelectric and mechanical properties of CoSb_(3) has been demonstrated by adjusting the composition with the addition of an increasing number of elements.However,such a strategy may negatively impact processing repeatability and composition control.In this work,singleelement-filled skutterudite is engineered to have high thermoelectric and mechanical performances.Increased Yb filling fraction is found to increase phonon scattering,whereas cryogenic grinding contributes additional microstructural scattering.A peak zT of 1.55 and an average zT of about 1.09,which is comparable to the reported results of multiple-filled SKDs,are realized by the combination of simple composition and microstructure engineering.Furthermore,the mechanical properties of Yb single-filled CoSb_(3) skutterudite are improved by manipulation of the microstructure through cryogenic grinding.These findings highlight the realistic prospect of producing high-performance thermoelectric materials with reduced compositional complexity.展开更多
Cu-based chalcogenides have received increasing attention as promising thermoelectric materials due to their high efficiency,tunable transport properties,high elemental abundance and low toxicity.In this review,we sum...Cu-based chalcogenides have received increasing attention as promising thermoelectric materials due to their high efficiency,tunable transport properties,high elemental abundance and low toxicity.In this review,we summarize the recent research progress on this large family compounds covering diamond-like chalcogenides and liquid-like Cu2X (X=S,Se,Te)binary compounds as well as their multinary derivatives.These materials have the general features of two sublattices to decouple electron and phonon transport properties.On the one hand,the complex crystal structure and the disordered or even liquid-like sublattice bring about an intrinsically low lattice thermal conductivity.On the other hand, the rigid sublattice constitutes the charge-transport network, maintaining a decent electrical performance.For specific material systems,we demonstrate their unique structural features and outline the structure-performance correlation. Various design strategies including doping,alloying,band engineering and nanostructure architecture,covering nearly all the material scale,are also presented.Finally,the potential of the application of Cu-based chalcogenides as high-performance thermoelectric materials is briefly discussed from material design to device development.展开更多
Background: The increase in global population, climate change and stagnancy in crop yield on unit land area basis in recent decades urgently call for a new approach to support contemporary crop improvements, ePlant i...Background: The increase in global population, climate change and stagnancy in crop yield on unit land area basis in recent decades urgently call for a new approach to support contemporary crop improvements, ePlant is a mathematical model of plant growth and development with a high level of mechanistic details to meet this challenge. Results: ePlant integrates modules developed for processes occurring at drastically different temporal (10-8-106 seconds) and spatial (10-10-10 meters) scales, incorporating diverse physical, biophysical and biochemical processes including gene regulation, metabolic reaction, substrate transport and diffusion, energy absorption, transfer and conversion, organ morphogenesis, plant environment interaction, etc. Individual modules are developed using a divide-and-conquer approach; modules at different temporal and spatial scales are integrated through transfer variables. We further propose a supervised learning procedure based on information geometry to combine model and data for both knowledge discovery and model extension or advances. We finally discuss the recent formation of a global consortium, which includes experts in plant biology, computer science, statistics, agronomy, phenomics, etc. aiming to expedite the development and application of ePlant or its equivalents by promoting a new model development paradigm where models are developed as a community effort instead of driven mainly by individual labs' effort. Conclusions: ePlant, as a major research tool to support quantitative and predictive plant science research, will play a crucial role in the future model guided crop engineering, breeding and agronomy.展开更多
A large number of genes related to source, sink,and flow have been identified after decades of research in plant genetics. Unfortunately, these genes have not been effectively utilized in modern crop breeding. This pe...A large number of genes related to source, sink,and flow have been identified after decades of research in plant genetics. Unfortunately, these genes have not been effectively utilized in modern crop breeding. This perspective paper aims to examine the reasons behind such a phenomenon and propose a strategy to resolve this situation. Specifically, we first systematically survey the currently cloned genes related to source, sink, and flow;then we discuss three factors hindering effective application of these identified genes, which include the lack of effective methods to identify limiting or critical steps in a signaling network, the misplacement of emphasis on properties, at the leaf, instead of the whole canopy level,and the non-linear complex interaction between source,sink, and flow. Finally, we propose the development of systems models of source, sink and flow, together with a detailed simulation of interactions between them and their surrounding environments, to guide effective use of the identified elements in modern rice breeding. These systems models will contribute directly to the definition of crop ideotype and also identification of critical features and parameters that limit the yield potential in current cultivars.展开更多
Canopy photosynthesis is the sum of photosynthesis of all above-ground photosynthetic tissues.Quantitative roles of nonfoliar tissues in canopy photosynthesis remain elusive due to methodology limitations.Here,we deve...Canopy photosynthesis is the sum of photosynthesis of all above-ground photosynthetic tissues.Quantitative roles of nonfoliar tissues in canopy photosynthesis remain elusive due to methodology limitations.Here,we develop the first complete canopy photosynthesis model incorporating all above-ground photosynthetic tissues and validate this model on wheat with state-of-the-art gas exchange measurement facilities.展开更多
Thermal conductivity is one of the most fundamental properties of materials with the value being determined by nearly all-scale structural features and multiple physical processes.Rapidly judging material’s thermal c...Thermal conductivity is one of the most fundamental properties of materials with the value being determined by nearly all-scale structural features and multiple physical processes.Rapidly judging material’s thermal conductivity is extremely important but challenging for the applications.The material genome paradigm offers a revolutionary way to efficiently screen and discover materials with designed properties by using accessible indicators.But such a performance indicator for thermal conductivity is quite difficult to propose due to the existence of multiple mechanisms and processes,especially for the materials with complex structures such as chalcogenides.In this study,the number mismatch between cations and anions is proposed as a practical performance indicator for lattice thermal conductivity in complex copper and silver chalcogenides,which can be used to explain the observed experimental data and find new low thermal conductivity materials.Such a number mismatch brings about rich phenomena to affect thermal conductivity including the complication of the unit cell and the creation of chemical hierarchy,point defects,rattling modes and lone-pair electrons.It is expected that this rich-connotation performance indicator can be also extended to other complex materials to discover designed thermal conductivities.展开更多
文摘The design thinking approach transforms student’s learning process to connect with real-world experience, making connections between knowledge and improving critical thinking and problem-solving capability. Previous research has focused on what design thinking is taught (content) and how it is taught (learning modes and assessment). However, there needs to be an integrative approach in the context of ecotourism education. Therefore, applying Wrigley and Straker’s Educational Design Ladder mode, this study develops an Ecotourism Design Thinking Curriculum framework to combine the ecotourism content, teaching/learning mode and assessment.
基金supported by the National Natural Science Foundation of China(No.30660203)the National Science and Technology Major Project(No.2013ZX10002009)the Key laboratory of High-Incidence Tumor Prevention (Guangxi Medical University),Ministry of Education(No.GK2015-ZZ06)
文摘Objective:To investigate the prevalence of metabolically healthy obesity(MHO)and its relationship with incidence of metabolic syndrome(MetS),type 2diabetes mellitus(T2DM)and hypertension in individuals in the city of Yulin.Methods:We studied 1,666 participants,aged over18years at baseline,with free of components of the MetS except waist criteria.Participants were divided into three groups based on body mass index(Ibm):lean/normal weight(Ibm<23kg/m2),overweight(Ibm,23-24.9kg/m2),obesity(Ibm≥25 kg/m2).The cumulative incidence of MetS,T2DM and hypertension over 5.21years among groups was assessed.Results:The prevalence of MHO was 19.5%in the baseline population.During an average 5.21year follow-up,the cumulative incidence of MetS,T2DM and hypertension in1,666participants were 16.4%,19.1%and 3.9%,respectively.The obesity group had a significantly higher cumulative incidence of MetS(16.4%vs.3.2%,P<0.001),hypertension(19.1%vs.3.7%,P<0.001),and T2DM(3.9%vs.1.6%,P<0.001)compared to the lean/normal weight group.Each kg/m2 of Ibm carried increased risk for T2DM(19%),hypertension(11%)and MetS(13%).Conclusion:Metabolically healthy obesity individuals confer increased risk for hypertension,T2DM and the MetS than their non-obese counterparts.
基金supported by the National Natural Science Foundation of China (No. 30660203)the National Science and Technology Major Project (No. 2013ZX10002009)the Key laboratory of High- Incidence Tumor Prevention (Guangxi Medical University),Ministry of Education(No. GK2015-ZZ06)
文摘Objective: Recent reports suggest that Cepharanthine(CEP),a natural alkaloid extracted from the roots of Stephania Cepharanthine Hayata,can inhibit the proliferation of various cancer cells,but few studies focus on its radiosensitization in nasopharyngeal carcinoma(NPC)cells. The aim of this study was to explore the radiosensitization effect and the potential mechanisms of CEP on nasopharyngeal carcinoma cell lines CNE-1 and CNE-2. Methods: The NPC cell lines CNE-1 and CNE-2 were treated with CEP(IC50)for 48 h before irration(IR);clonogenic survival was then assessed. The apoptosis and cell cycle progression were using flow cytometry.The DNA damage repair and cycle-regulating proteins were evaluated by Western blot analysis. Results: CEP could inhibit cell growth in both cell lines. The combination of CEP and radiation promote cell cycle G2/M phase arrest and apoptosis in CNE-1 and CNE-2 cells.DNA damage repair analysis showed that CEP has an inhibitory effect on DNA repair of CNE-1 and CNE-2 cells after radiation.Conclusion: CEP enhances tumor radioresponse through multiple mechanisms that may involve the halted cell cycle progression at G2/M phase and the inhibition of DNA repair after exposure to radiation.
基金financially supported by the National Key Research and Development Program of China(Grant No.2019YFE0103500)the National Nature Science Foundation of China(NSFC)(Grant Nos.U2141208 and 52102330)+1 种基金and the In-ternational Partnership Program of Chinese Academy of Sciences(Grant No.121631KYSB20200012)the support from CAS Key Technology Talent Program.
文摘ZrCoSb-based half-Heusler(HH)compounds are among the most promising thermoelectric(TE)materials for high-temperature power generation.Oxidation resistance is one of the key issues for realizing the practical application of TE materials for long-term service in the ambient working environment.In this work,the oxidation behavior of Zr_(0.5)Hf_(0.5)CoSb_(0.8)Sn_(0.2)(ZHCSS)half-Heusler is systematically studied in the service temperature range from 873 to 1073 K.It is revealed that three typical layers of oxidation products tend to form on the surface of HH sample,namely,the dense oxide layer(DOL)composed of(Zr,Hf)O_(2) and CoSb,the alternate oxide layer(AOL)composed of repeated(Zr,Hf)O_(2) and CoSb_(2)O_(6)/Co_(3)O_(4),and the CoSb layer between the DOL and AOL.The mass gain during oxidation is mainly caused by the rapid growth of AOL,which is controlled by the outward diffusion of Zr/Hf and the inward diffusion of oxygen.The formation of a continuous CoSb layer and DOL is found beneficial to block the outward diffusion of Zr/Hf.Based on the analysis of the dominant factors on the outward and inward diffusions as well as the reaction activation energy,a simple approach is proposed to improve the oxidation resistance of Zr_(0.5)Hf_(0.5)CoSb_(0.8)Sn_(0.2)by pre-oxidizing the sample in low oxygen pressure to form the dense(Zr,Hf)O_(2) and CoSb layers as oxidation protecting and/or diffusion blocking layers.The oxidation test shows the effectiveness of such pre-oxidation on the formation and growth of the AOL and therefore on improving the service stability of Zr_(0.5)Hf_(0.5)CoSb_(0.8)Sn_(0.2)at high temperatures in the air.
基金funded by Natural Science Foundation of China(Nos.51774096,51871053)Shanghai Committee of Science and Technology(Nos.16JC1401800,18JC1411200)+1 种基金supported by the NASA Science Missions Directorate under the Radioisotope Power Systems Programsupport from the National Science Foundation(DMREF-1333335 and DMREF-1729487).
文摘A broad tunability of the thermoelectric and mechanical properties of CoSb_(3) has been demonstrated by adjusting the composition with the addition of an increasing number of elements.However,such a strategy may negatively impact processing repeatability and composition control.In this work,singleelement-filled skutterudite is engineered to have high thermoelectric and mechanical performances.Increased Yb filling fraction is found to increase phonon scattering,whereas cryogenic grinding contributes additional microstructural scattering.A peak zT of 1.55 and an average zT of about 1.09,which is comparable to the reported results of multiple-filled SKDs,are realized by the combination of simple composition and microstructure engineering.Furthermore,the mechanical properties of Yb single-filled CoSb_(3) skutterudite are improved by manipulation of the microstructure through cryogenic grinding.These findings highlight the realistic prospect of producing high-performance thermoelectric materials with reduced compositional complexity.
基金supported by the National Key Research and Development Program of China (2018YFB0703600)the National Natural Science Foundation of China (51625205)+3 种基金 the Key Research Program of Chinese Academy of Sciences (KFZD-SW-421)Program of Shanghai Subject Chief Scientist (16XD1403900)Youth Innovation Promotion Association, CAS (2016232)Shanghai Sailing Program (18YF1426700).
文摘Cu-based chalcogenides have received increasing attention as promising thermoelectric materials due to their high efficiency,tunable transport properties,high elemental abundance and low toxicity.In this review,we summarize the recent research progress on this large family compounds covering diamond-like chalcogenides and liquid-like Cu2X (X=S,Se,Te)binary compounds as well as their multinary derivatives.These materials have the general features of two sublattices to decouple electron and phonon transport properties.On the one hand,the complex crystal structure and the disordered or even liquid-like sublattice bring about an intrinsically low lattice thermal conductivity.On the other hand, the rigid sublattice constitutes the charge-transport network, maintaining a decent electrical performance.For specific material systems,we demonstrate their unique structural features and outline the structure-performance correlation. Various design strategies including doping,alloying,band engineering and nanostructure architecture,covering nearly all the material scale,are also presented.Finally,the potential of the application of Cu-based chalcogenides as high-performance thermoelectric materials is briefly discussed from material design to device development.
基金The work in XGZ's lab is supported by CAS strategic leading project on designer breeding by molecular module (No. XDA08020301), the National High Technology Development Plan of the Ministry of Science and Technology of China (2014AA101601), the National Natural Science Foundation of China (No. C020401), the National Key Basic Research Program of China (No. 2015CB150104), Bill and Melinda Gates Foundation (No. OPP1060461), CAS-CSIRO Cooperative Research Program (No. GJHZ1501).
文摘Background: The increase in global population, climate change and stagnancy in crop yield on unit land area basis in recent decades urgently call for a new approach to support contemporary crop improvements, ePlant is a mathematical model of plant growth and development with a high level of mechanistic details to meet this challenge. Results: ePlant integrates modules developed for processes occurring at drastically different temporal (10-8-106 seconds) and spatial (10-10-10 meters) scales, incorporating diverse physical, biophysical and biochemical processes including gene regulation, metabolic reaction, substrate transport and diffusion, energy absorption, transfer and conversion, organ morphogenesis, plant environment interaction, etc. Individual modules are developed using a divide-and-conquer approach; modules at different temporal and spatial scales are integrated through transfer variables. We further propose a supervised learning procedure based on information geometry to combine model and data for both knowledge discovery and model extension or advances. We finally discuss the recent formation of a global consortium, which includes experts in plant biology, computer science, statistics, agronomy, phenomics, etc. aiming to expedite the development and application of ePlant or its equivalents by promoting a new model development paradigm where models are developed as a community effort instead of driven mainly by individual labs' effort. Conclusions: ePlant, as a major research tool to support quantitative and predictive plant science research, will play a crucial role in the future model guided crop engineering, breeding and agronomy.
基金Research funding by the CAS Strategic Leading Project (XDA08020301)National Natural Science Foundation of China (31501240)+4 种基金the open funding from State Key Laboratory of Hybrid Rice (2016KF06)the CAS-CSIRO collaboration grant (GJHZ1501)National Key Research and Development Program of China (2017YFD0301502)the project of Hunan Provincial Natural Science Foundation of China (2018JJ2286)the project of Hunan Academy of Agricultural Sciences (2017JC04)
文摘A large number of genes related to source, sink,and flow have been identified after decades of research in plant genetics. Unfortunately, these genes have not been effectively utilized in modern crop breeding. This perspective paper aims to examine the reasons behind such a phenomenon and propose a strategy to resolve this situation. Specifically, we first systematically survey the currently cloned genes related to source, sink, and flow;then we discuss three factors hindering effective application of these identified genes, which include the lack of effective methods to identify limiting or critical steps in a signaling network, the misplacement of emphasis on properties, at the leaf, instead of the whole canopy level,and the non-linear complex interaction between source,sink, and flow. Finally, we propose the development of systems models of source, sink and flow, together with a detailed simulation of interactions between them and their surrounding environments, to guide effective use of the identified elements in modern rice breeding. These systems models will contribute directly to the definition of crop ideotype and also identification of critical features and parameters that limit the yield potential in current cultivars.
基金This work was supported by the open research fund of the State Key Laboratory of Hybrid Rice(Hunan Hybrid Rice Research Center)to T.C.(2020KF01)the National Natural Science Foundation of China to T.C.(32000285)and Q.S.(31970378)+1 种基金the Chinese Academy of Science strategic lead-ing project to X.Z.(XDB27020105)the funding from the BASF Belgium Coordination Center-Innovation Center Gent to X.Z..
文摘Canopy photosynthesis is the sum of photosynthesis of all above-ground photosynthetic tissues.Quantitative roles of nonfoliar tissues in canopy photosynthesis remain elusive due to methodology limitations.Here,we develop the first complete canopy photosynthesis model incorporating all above-ground photosynthetic tissues and validate this model on wheat with state-of-the-art gas exchange measurement facilities.
基金This work is supported by the National Key Research and Development Program of China(2018YFB0703600)the National Natural Science Foundation of China(51625205,91963208,and 51802333)+1 种基金the Key Research Program of Chinese Academy of Sciences(KFZD-SW-421)the Youth Innovation Promotion Association of CAS(2016232).
文摘Thermal conductivity is one of the most fundamental properties of materials with the value being determined by nearly all-scale structural features and multiple physical processes.Rapidly judging material’s thermal conductivity is extremely important but challenging for the applications.The material genome paradigm offers a revolutionary way to efficiently screen and discover materials with designed properties by using accessible indicators.But such a performance indicator for thermal conductivity is quite difficult to propose due to the existence of multiple mechanisms and processes,especially for the materials with complex structures such as chalcogenides.In this study,the number mismatch between cations and anions is proposed as a practical performance indicator for lattice thermal conductivity in complex copper and silver chalcogenides,which can be used to explain the observed experimental data and find new low thermal conductivity materials.Such a number mismatch brings about rich phenomena to affect thermal conductivity including the complication of the unit cell and the creation of chemical hierarchy,point defects,rattling modes and lone-pair electrons.It is expected that this rich-connotation performance indicator can be also extended to other complex materials to discover designed thermal conductivities.