Local soil conditions can significantly modify the seismic motion expected on the soil surface.In most cases,the indications concerning the influence of the underlying soil provided by the in-force European and Italia...Local soil conditions can significantly modify the seismic motion expected on the soil surface.In most cases,the indications concerning the influence of the underlying soil provided by the in-force European and Italian Building Codes underestimate the real seismic amplification effects.For this reason,numerical analyses of the local seismic response(LSR)have been encouraged to estimate the soil filtering effects.These analyses are generally performed in free-field conditions,ignoring the presence of superstructures and,therefore,the effects of dynamic soil-structure interaction(DSSI).Moreover,many studies on DSSI are characterised by a sophisticated modelling of the structure and an approximate modelling of the soil(using springs and dashpots at the foundation level);while others are characterised by a sophisticated modelling of the soil and an approximate modelling of the structure(considered as a simple linear elastic structure or a single degree of freedom system).This paper presents a set of finite element method(FEM)analyses on a fully-coupled soil-structure system for a reinforced concrete building located in Fleri(Catania,Italy).The building,designed for gravity loads only,was severely damaged during the 26 December 2018 earthquake.The soil was modelled considering an equivalent visco-elastic behaviour,while the structure was modelled assuming both the visco-elastic and visco-inelastic behaviours.The comparison made between the results of the FEM analyses and the observed damage is valuable.展开更多
China has promulgated a series of policies including the Western Development Program, the Grain for Green Project, agricultural support policies and building a new countryside strategy to eliminate east-west differenc...China has promulgated a series of policies including the Western Development Program, the Grain for Green Project, agricultural support policies and building a new countryside strategy to eliminate east-west differences and urban-rural disparities since the late 1990s. This paper gives a holistic examination on local responses to the four typical macro socio-economic development policies and their effects on rural system based on a case study of a mountainous village in southern Sichuan Province. The results showed that the policies have not moved the case study village from its historically marginal status. To some extent, its socio-economic situation might have been worsened by accelerated out- migration of the youth, loss of agricultural land due to afforestation and industrial plants, increased fire hazard due to afforestation and reforestation, increased environmental pollution due to industrial enterprises attracted to the village and a steep decline in agricultural production due to loss of and inefficient use of cultivated land. Factors causing local villages' dilemmas include the nonuniformity of actors' objectives, finiteness of villagers' abilities, and the imperfect incentive and restraint mechanism for local government's activities under existing policy framework composed of uncoordinated one-size-fits- all policies. We suggest that China's rural policy in the new period should gradually shift from a sectoral to a place-based one, from top-down incentives to the development of bottom-up projects, and fully recognize the diversity of rural space, so as to lift localcapacities and make good use of the knowledge shared by different actors. Moreover, it is also necessary to integrate the various sectoral policies, and improve the interministerial and interdepartmental coordination of rural policies at regional and local levels.展开更多
In this work a Support Vector Machine Regression(SVMR) algorithm is used to calculate local magnitude(MI) using only five seconds of signal after the P wave onset of one three component seismic station. This algor...In this work a Support Vector Machine Regression(SVMR) algorithm is used to calculate local magnitude(MI) using only five seconds of signal after the P wave onset of one three component seismic station. This algorithm was trained with 863 records of historical earthquakes, where the input regression parameters were an exponential function of the waveform envelope estimated by least squares and the maximum value of the observed waveform for each component in a single station. Ten-fold cross validation was applied for a normalized polynomial kernel obtaining the mean absolute error for different exponents and complexity parameters. The local magnitude(MI) could be estimated with 0.19 units of mean absolute error. The proposed algorithm is easy to implement in hardware and may be used directly after the field seismological sensor to generate fast decisions at seismological control centers, increasing the possibility of having an effective reaction.展开更多
Current developments on fatigue life prediction methods have been systematically reviewed.In con- sideration of the irreversibility of energy dissipation during fatigue damage process,the main contents for fatigue dam...Current developments on fatigue life prediction methods have been systematically reviewed.In con- sideration of the irreversibility of energy dissipation during fatigue damage process,the main contents for fatigue damage estimation and localized equivalence as well as simulation models have been established.A frame of energy-based fatigue life prediction method has been proposed,meanwhile, the procedure in application to a practical structure component has been described.展开更多
Piezoresponse force microscopy(PFM)is an indispensable tool in the investigation of local electromechanical responses and polarization switching.The acquired data provide spatial information on the local disparity of ...Piezoresponse force microscopy(PFM)is an indispensable tool in the investigation of local electromechanical responses and polarization switching.The acquired data provide spatial information on the local disparity of polarization switching and electromechanical responses,making this technique advantageous over macroscopic approaches.Despite its widespread application in ferroelectrics,it has rarely been used to investigate the ferrielectric(FiE)behaviors in antiferroelectric(AFE)materials.Herein,the PFM was utilized to study the local electromechanical behavior and distribution of FiE,and the AFE phases of PbZrO_(3)thin-film were studied,where only the FiE behavior is observable using a macroscopic approach.The FiE region resembles a ferroelectric material at low voltages but exhibits a unique on-field amplitude response at high voltages.In contrast,the AFE region only yields an observable response at high voltages.Phase-field simulations reveal the coexistence of AFE and FiE states as well as the phase-transition processes that underpin our experimental observations.Our work illustrates the usefulness of PFM as an analytical tool to characterize AFE/FiE materials and their phase-coexistence behavior,thereby providing insights to guide property modification and potential applications.展开更多
The Omicron variants have continued to cause severe acute respiratory syndrome coronavirus 2 infections.To better understand the anti-viral effects of vaccination on host-virus interactions during the outbreak of BA.2...The Omicron variants have continued to cause severe acute respiratory syndrome coronavirus 2 infections.To better understand the anti-viral effects of vaccination on host-virus interactions during the outbreak of BA.2.2 Omicron,we conducted RNA-seq transcriptome analysis on nasopharyngeal swabs from COVID-19 patients in Shanghai.This study was performed on selected cases from unvaccinated,fully vaccinated,and booster groups with the same founder virus infection background.We observed predominant immune cell chemotaxis and interleukin-1 production,as well as mucosal keratinization and epidermis development,in unvaccinated patients.In contrast,fully vaccinated subjects exhibited an obvious T-cell activation in the local immune response,whereas B-cell activation was higher in booster-vaccinated cases.In conclusion,our findings suggest that full or booster vaccination provides better adaptive immunity and relieve inflammation at the nasopharyngeal site,thereby reducing the risk of cytokine storm during breakthrough infection.展开更多
Damage in the structures alters the structural dynamic behavior. Damage generally occurs locally in the components of structures, and its effect often exhibits in the changes of both local and global characteristics o...Damage in the structures alters the structural dynamic behavior. Damage generally occurs locally in the components of structures, and its effect often exhibits in the changes of both local and global characteristics of structures. Better understanding of this relationship helps to monitor and assess the condition of structures and develop dynamics-based structural health monitoring techniques. In this study, the relationship between the local damage and structural dynamic behavior is investigated. To validate the concept, an experiment of a three-dimensional (3-D) steel frame structure with different magnitudes of local damage is illustrated. The experimental results indicate that the change of global resonant response between the intact and damage structure is not obvious. The change of local resonant responses measured near the location of saw-cut crack damage is quite significant. The experimental study conducted indicates that the local resonant responses at the low order resonance can be used as an effective damage identification method to detect and quantify the local damage in the 3D frame structures.展开更多
Environmental stresses that perturb plant Hwater relations influence abscisic acid(ABA) concentrations, but it is unclear whether long-distance ABA transport contributes to changes in local ABA levels. To determine th...Environmental stresses that perturb plant Hwater relations influence abscisic acid(ABA) concentrations, but it is unclear whether long-distance ABA transport contributes to changes in local ABA levels. To determine the physiological relevance of ABA transport, we made reciprocal-and self-grafts of ABA-deficient flacca mutant and wild-type(WT) tomato plants, in which low phosphorus(P) conditions decreased ABA concentrations while salinity increased ABA concentrations. Whereas foliar ABA concentrations in the WT scions were rootstock independent under control conditions, salinity resulted in long-distance transport of ABA: flacca scions had approximately twice as much ABA when grafted on WT rootstocks compared to flacca rootstocks. Root ABA concentrations were scion dependent: both WT and flacca rootstocks had less ABA with the flacca mutant scion than with the WT scion under control conditions. In WT scions, whereas rootstock genotype had limited effects on stomatal conductance under control conditions, a flacca rootstock decreased leaf area of stressed plants, presumably due to attenuated root-to-shoot ABA transport. In flacca scions, a WT rootstock decreased stomatal conductance but increased leaf area of stressed plants, likely due to enhanced root-to-shoot ABA transport. Thus, long-distance ABA transport can affect responses in distal tissues by changing local ABA concentrations.展开更多
基金Financial support provided by the Dipartimento di Protezione Civile/Rete Laboratori Universitari Ingegneria Sismica e Strutturale,in Italian(DPC/ReLUIS)2019-2021 Research Project,funded by the Civil Protection Department,allowed the authors to achieve the results reported in this paper.
文摘Local soil conditions can significantly modify the seismic motion expected on the soil surface.In most cases,the indications concerning the influence of the underlying soil provided by the in-force European and Italian Building Codes underestimate the real seismic amplification effects.For this reason,numerical analyses of the local seismic response(LSR)have been encouraged to estimate the soil filtering effects.These analyses are generally performed in free-field conditions,ignoring the presence of superstructures and,therefore,the effects of dynamic soil-structure interaction(DSSI).Moreover,many studies on DSSI are characterised by a sophisticated modelling of the structure and an approximate modelling of the soil(using springs and dashpots at the foundation level);while others are characterised by a sophisticated modelling of the soil and an approximate modelling of the structure(considered as a simple linear elastic structure or a single degree of freedom system).This paper presents a set of finite element method(FEM)analyses on a fully-coupled soil-structure system for a reinforced concrete building located in Fleri(Catania,Italy).The building,designed for gravity loads only,was severely damaged during the 26 December 2018 earthquake.The soil was modelled considering an equivalent visco-elastic behaviour,while the structure was modelled assuming both the visco-elastic and visco-inelastic behaviours.The comparison made between the results of the FEM analyses and the observed damage is valuable.
基金supported by the National Natural Science Foundation of China(Grant Nos.41201176,41130748and41171149)China Postdoctoral Science Foundation(Grant Nos.2011M500029 and 2012T50126)
文摘China has promulgated a series of policies including the Western Development Program, the Grain for Green Project, agricultural support policies and building a new countryside strategy to eliminate east-west differences and urban-rural disparities since the late 1990s. This paper gives a holistic examination on local responses to the four typical macro socio-economic development policies and their effects on rural system based on a case study of a mountainous village in southern Sichuan Province. The results showed that the policies have not moved the case study village from its historically marginal status. To some extent, its socio-economic situation might have been worsened by accelerated out- migration of the youth, loss of agricultural land due to afforestation and industrial plants, increased fire hazard due to afforestation and reforestation, increased environmental pollution due to industrial enterprises attracted to the village and a steep decline in agricultural production due to loss of and inefficient use of cultivated land. Factors causing local villages' dilemmas include the nonuniformity of actors' objectives, finiteness of villagers' abilities, and the imperfect incentive and restraint mechanism for local government's activities under existing policy framework composed of uncoordinated one-size-fits- all policies. We suggest that China's rural policy in the new period should gradually shift from a sectoral to a place-based one, from top-down incentives to the development of bottom-up projects, and fully recognize the diversity of rural space, so as to lift localcapacities and make good use of the knowledge shared by different actors. Moreover, it is also necessary to integrate the various sectoral policies, and improve the interministerial and interdepartmental coordination of rural policies at regional and local levels.
文摘In this work a Support Vector Machine Regression(SVMR) algorithm is used to calculate local magnitude(MI) using only five seconds of signal after the P wave onset of one three component seismic station. This algorithm was trained with 863 records of historical earthquakes, where the input regression parameters were an exponential function of the waveform envelope estimated by least squares and the maximum value of the observed waveform for each component in a single station. Ten-fold cross validation was applied for a normalized polynomial kernel obtaining the mean absolute error for different exponents and complexity parameters. The local magnitude(MI) could be estimated with 0.19 units of mean absolute error. The proposed algorithm is easy to implement in hardware and may be used directly after the field seismological sensor to generate fast decisions at seismological control centers, increasing the possibility of having an effective reaction.
文摘Current developments on fatigue life prediction methods have been systematically reviewed.In con- sideration of the irreversibility of energy dissipation during fatigue damage process,the main contents for fatigue damage estimation and localized equivalence as well as simulation models have been established.A frame of energy-based fatigue life prediction method has been proposed,meanwhile, the procedure in application to a practical structure component has been described.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIP)(No.2019R1I1A1A01063888)the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(No.2019R1A6A1A03033215)F.P.Z.acknowledges the Alexander von Humboldt Foundation(AvH)for the fellowship with award number 1203828,and Z.L.acknowledges the LOEWE program of the State of Hesse,Germany,within the project FLAME(Fermi Level Engineering of Antiferroelectric Materials for Energy Storage and Insulation Systems).
文摘Piezoresponse force microscopy(PFM)is an indispensable tool in the investigation of local electromechanical responses and polarization switching.The acquired data provide spatial information on the local disparity of polarization switching and electromechanical responses,making this technique advantageous over macroscopic approaches.Despite its widespread application in ferroelectrics,it has rarely been used to investigate the ferrielectric(FiE)behaviors in antiferroelectric(AFE)materials.Herein,the PFM was utilized to study the local electromechanical behavior and distribution of FiE,and the AFE phases of PbZrO_(3)thin-film were studied,where only the FiE behavior is observable using a macroscopic approach.The FiE region resembles a ferroelectric material at low voltages but exhibits a unique on-field amplitude response at high voltages.In contrast,the AFE region only yields an observable response at high voltages.Phase-field simulations reveal the coexistence of AFE and FiE states as well as the phase-transition processes that underpin our experimental observations.Our work illustrates the usefulness of PFM as an analytical tool to characterize AFE/FiE materials and their phase-coexistence behavior,thereby providing insights to guide property modification and potential applications.
基金supported by the National Natural Science Foundation of China(Nos 92169212 and 82161138018)Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response(20dz2260100)+1 种基金Key Discipline Construction Plan fromShanghaiMunicipalHealth Commission(GWV-10.1-XK01)ShanghaiMunicipal Science and Technology Major Project(HS2021SHZX001).
文摘The Omicron variants have continued to cause severe acute respiratory syndrome coronavirus 2 infections.To better understand the anti-viral effects of vaccination on host-virus interactions during the outbreak of BA.2.2 Omicron,we conducted RNA-seq transcriptome analysis on nasopharyngeal swabs from COVID-19 patients in Shanghai.This study was performed on selected cases from unvaccinated,fully vaccinated,and booster groups with the same founder virus infection background.We observed predominant immune cell chemotaxis and interleukin-1 production,as well as mucosal keratinization and epidermis development,in unvaccinated patients.In contrast,fully vaccinated subjects exhibited an obvious T-cell activation in the local immune response,whereas B-cell activation was higher in booster-vaccinated cases.In conclusion,our findings suggest that full or booster vaccination provides better adaptive immunity and relieve inflammation at the nasopharyngeal site,thereby reducing the risk of cytokine storm during breakthrough infection.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11132003 and 51079045)
文摘Damage in the structures alters the structural dynamic behavior. Damage generally occurs locally in the components of structures, and its effect often exhibits in the changes of both local and global characteristics of structures. Better understanding of this relationship helps to monitor and assess the condition of structures and develop dynamics-based structural health monitoring techniques. In this study, the relationship between the local damage and structural dynamic behavior is investigated. To validate the concept, an experiment of a three-dimensional (3-D) steel frame structure with different magnitudes of local damage is illustrated. The experimental results indicate that the change of global resonant response between the intact and damage structure is not obvious. The change of local resonant responses measured near the location of saw-cut crack damage is quite significant. The experimental study conducted indicates that the local resonant responses at the low order resonance can be used as an effective damage identification method to detect and quantify the local damage in the 3D frame structures.
基金supported by the National Natural Science Foundation of China (31300327)Excellent Young Scientist Foundation of Henan University (yqpy20140030)the EU ROOTOPOWER (289365) project for supporting research on grafting
文摘Environmental stresses that perturb plant Hwater relations influence abscisic acid(ABA) concentrations, but it is unclear whether long-distance ABA transport contributes to changes in local ABA levels. To determine the physiological relevance of ABA transport, we made reciprocal-and self-grafts of ABA-deficient flacca mutant and wild-type(WT) tomato plants, in which low phosphorus(P) conditions decreased ABA concentrations while salinity increased ABA concentrations. Whereas foliar ABA concentrations in the WT scions were rootstock independent under control conditions, salinity resulted in long-distance transport of ABA: flacca scions had approximately twice as much ABA when grafted on WT rootstocks compared to flacca rootstocks. Root ABA concentrations were scion dependent: both WT and flacca rootstocks had less ABA with the flacca mutant scion than with the WT scion under control conditions. In WT scions, whereas rootstock genotype had limited effects on stomatal conductance under control conditions, a flacca rootstock decreased leaf area of stressed plants, presumably due to attenuated root-to-shoot ABA transport. In flacca scions, a WT rootstock decreased stomatal conductance but increased leaf area of stressed plants, likely due to enhanced root-to-shoot ABA transport. Thus, long-distance ABA transport can affect responses in distal tissues by changing local ABA concentrations.