Structural health monitoring is widely utilized in outdoor environments,especially under harsh conditions,which can introduce noise into the monitoring system.Therefore,designing an effective denoising strategy to enh...Structural health monitoring is widely utilized in outdoor environments,especially under harsh conditions,which can introduce noise into the monitoring system.Therefore,designing an effective denoising strategy to enhance the performance of guided wave damage detection in noisy environments is crucial.This paper introduces a local temporal principal component analysis(PCA)reconstruction approach for denoising guided waves prior to implementing unsupervised damage detection,achieved through novel autoencoder-based reconstruction.Experimental results demonstrate that the proposed denoising method significantly enhances damage detection performance when guided waves are contaminated by noise,with SNR values ranging from 10 to-5 dB.Following the implementation of the proposed denoising approach,the AUC score can elevate from 0.65 to 0.96 when dealing with guided waves corrputed by noise at a level of-5 dB.Additionally,the paper provides guidance on selecting the appropriate number of components used in the denoising PCA reconstruction,aiding in the optimization of the damage detection in noisy conditions.展开更多
Objective In 2006,Alzheimer's Association Victoria Australia funded the authors to conduct a systematic review of the community education literature in order to assist the development of their own community educat...Objective In 2006,Alzheimer's Association Victoria Australia funded the authors to conduct a systematic review of the community education literature in order to assist the development of their own community education strategy.Methods This paper draws upon this research project to convey the predominant messages arising consistently across the evidence base relating to key national health priority areas.Particular attention is given to exploring the needs of minority groups.Results The evidence reviewed indicates the need for multi-faceted intervention approaches that are carefully planned and assessed to ensure sufficient exposure of the target audience to the health messages.Conclusion Such approaches remain to be empirically tested within the context of dementia risk reduction.Nevertheless,there are consistent models in the evidence base that can be applied with confidence to community education in the current domain.展开更多
The satellite-based vegetation condition index(VCI) and temperature condition index(TCI) have been used extensively for drought detection and tracking, the assessment of weather impacts on vegetation and evaluation of...The satellite-based vegetation condition index(VCI) and temperature condition index(TCI) have been used extensively for drought detection and tracking, the assessment of weather impacts on vegetation and evaluation of the health and productivity of vegetation. In this study, in order to detect and monitor the growth condition of vegetation, we have collected data on vegetation indices and land surface temperature derived from MODIS(2001-2012) and defined a vegetation health index(VHI) based on VCI and TCI for assessing vegetation health condition in the Three Gorges Area, China(TGA). The results of the study show that temporal and spatial characteristics of vegetation health condition can be detected, tracked and mapped by the VHI index. In most parts of the TGA, the vegetation health condition showed an overall increasing trend during the study period, especially in Wulong, Fengdu, Shizhu and other regions located in the midstream sections of the Three Gorges Reservoir. In addition, the four studied vegetation types all showed clear increasing trends during the study period. The increasing trend in the vegetation health condition shows a strong positive correlation with topographical slope and altitude(below 500 m). Over the seasons, this trend is strongest in autumn, followed by spring. However, the correlations between vegetation health condition and climatic factors are more frequently significant in summer and winter than in autumn and spring. The vegetation health condition has been low in 2006 and 2011. This finding is consistent with the extreme weather conditions in those two years. However, only in the summer is vegetation health condition significantly correlated with three climatic factors in most of the study area. This result implies that vegetation growth may show a lagged response to climatic factors and may also be affected by human activities, including agricultural activities, industrial activities and other economic activities.展开更多
Soil cadmium(Cd)contamination resulted from mining and smelting is a major environmental concern,and health risk associated with Cd exposure to multi-media through muti-pathway is increasing.Cd concentrations in soils...Soil cadmium(Cd)contamination resulted from mining and smelting is a major environmental concern,and health risk associated with Cd exposure to multi-media through muti-pathway is increasing.Cd concentrations in soils,vegetables and paddy rice were investigated,and potential non-carcinogenic and carcinogenic health risks exposure to Cd were estimated at six villages around the Dabaoshan Mine,South China.A total of 87 soil samples were found to exceed the China's maximum permission level(MPL)for Cd,while the highest value of 4.42 mg/kg was found near irrigation ditch associated with Hengshi River in Xinyi(XY)Village.Cd contents in vegetables and rice exceeded the maximum permissible concentration by more than five times in every village.Cadmium accumulation in plants is in the order of celery>lactuca sativa L>Chinese cabbage>Romaine lettuce>asparagus lettuce>mustard>cabbage mustard>cabbage.The mean hazard quotient(HQ)of all villages is in the range of [5.29,25.75],and the mean values of cancer risk for investigated areas are more than 10 times greater than the USEPA(2009)threshold limit value of 10-4.Moreover,human non-carcinogenic and carcinogenic risks are mainly attributable to paddy rice intake,followed by vegetables intake,soil ingestion,inhalation,and dermal contact.The results indicate that Cd has a huge potential risk on human health for the local residents.展开更多
This paper proposes a health evaluation method for degrading systems subject to competing risks of dependent soft and hard failures. To characterize the time-varying degradation rate, the degradation process is determ...This paper proposes a health evaluation method for degrading systems subject to competing risks of dependent soft and hard failures. To characterize the time-varying degradation rate, the degradation process is determined by a non-stationary Gamma process and the soft failure is encountered when it exceeds a predefined critical level. For the hard failure, a Cox’s proportional hazard model is applied to describe the hazard rate of the time to system failure. The dependent relationship is modeled by incorporating the degradation process as a time-varying covariate into the Cox’s proportional hazard model. To facilitate the health characteristics evaluation, a discretization technique is applied both to the degradation process and the monitoring time.All health characteristics can be obtained in the explicit form using the transition probability matrix, which is computationally attractive for practical applications. Finally, a numerical analysis is carried out to show the effectiveness and the performance of the proposed health evaluation method.展开更多
It is well established in experimental animals and Humans that endothelial cells,which cover the luminal surface of all blood vessels,have a pivotal role in the control of vascular homeostasis.The protective effect of...It is well established in experimental animals and Humans that endothelial cells,which cover the luminal surface of all blood vessels,have a pivotal role in the control of vascular homeostasis.The protective effect of endothelial cells is mostly due to their ability to respond to circulating hormones,autacoids,blood-and platelet-derived factors,and also to blood flow by inducing potent vasoprotectivemechanismsincluding predominantlythe formation of nitric oxide(NO),and,often also to some extent,endothelium-derived hyperpolarization,and prostacyclin(PGI2).Besides being a potent vasodilator,NO also effectively prevents platelet activation and has anti-thrombotic and anti-atherosclerotic properties.An endothelial dysfunction characterized by a reduced generation of these endothelium-dependent vasodilator mechanisms associated with vascular oxidative stress and the formation of endothelium-derived contracting factors such as contractile prostanoids is often observed in most types of cardiovascular diseases including hypertension,hypercho⁃lesterolemia,diabetes,and also during physiological ageing in both experimental animals and Humans.Nutrition-derived polyphenols such as those from grapes,tea,cocoa,and berries have been shown to stimulate the endothelial formation of NO by activating the Src/PI3-kinase/Akt-dependent phosphorylation of endothelial NO synthase(eNOS)and to enhance eNOS expression.As a consequence,the active polyphenols will promote a sustained forma⁃tion of NO that contributes to protect the vascular system.Polyphenol-rich products have also been shown to improve an established endothelial dysfunction and to delay the onset of the induction of an endothelial dysfunction in several experimental models of cardiovascular diseases including hypertension and in ageing.Moreover,endothelial senescence characterized by cell cycle arrest and the acquisition of a pro-inflammatory and pro-atherothrombotic phenotype has been identified as an early event promotingthe development of endothelial dysfunc⁃tion.Premature endothelial senescence appears to affect,in particular,arterial sites at risk such as curvatures and bifur⁃cations that are characterized by disturbed flow and low shear stress.The pro-senescent process can be further increased in the presence of a high concentration of glucose,oxidized LDL,and angiotensinⅡ.Anthocyanin-rich products have been shown to accumulate preferentially in senescent endothelial cells,to reduce the expression of cell cycle regulators such as p16,p21 and p53,and to improve the endothelial function.The protective effect is mostly due to their ability to reduce vascular oxidative stress by inhibiting the overexpression of NADPH oxidase and the local angiotensin system.Thus,nutrition-derived polyphenols may be an interesting approach to delay the onset of risk factor-and ageing-related endothelial senescence and dysfunction and,hence,to promote vascular health.展开更多
基金National Science Foundation of Zhejiang under Contract(LY23E010001)。
文摘Structural health monitoring is widely utilized in outdoor environments,especially under harsh conditions,which can introduce noise into the monitoring system.Therefore,designing an effective denoising strategy to enhance the performance of guided wave damage detection in noisy environments is crucial.This paper introduces a local temporal principal component analysis(PCA)reconstruction approach for denoising guided waves prior to implementing unsupervised damage detection,achieved through novel autoencoder-based reconstruction.Experimental results demonstrate that the proposed denoising method significantly enhances damage detection performance when guided waves are contaminated by noise,with SNR values ranging from 10 to-5 dB.Following the implementation of the proposed denoising approach,the AUC score can elevate from 0.65 to 0.96 when dealing with guided waves corrputed by noise at a level of-5 dB.Additionally,the paper provides guidance on selecting the appropriate number of components used in the denoising PCA reconstruction,aiding in the optimization of the damage detection in noisy conditions.
文摘Objective In 2006,Alzheimer's Association Victoria Australia funded the authors to conduct a systematic review of the community education literature in order to assist the development of their own community education strategy.Methods This paper draws upon this research project to convey the predominant messages arising consistently across the evidence base relating to key national health priority areas.Particular attention is given to exploring the needs of minority groups.Results The evidence reviewed indicates the need for multi-faceted intervention approaches that are carefully planned and assessed to ensure sufficient exposure of the target audience to the health messages.Conclusion Such approaches remain to be empirically tested within the context of dementia risk reduction.Nevertheless,there are consistent models in the evidence base that can be applied with confidence to community education in the current domain.
基金Natural Science Foundation Project of CQ CSTC(CSTC2011jj A00025)
文摘The satellite-based vegetation condition index(VCI) and temperature condition index(TCI) have been used extensively for drought detection and tracking, the assessment of weather impacts on vegetation and evaluation of the health and productivity of vegetation. In this study, in order to detect and monitor the growth condition of vegetation, we have collected data on vegetation indices and land surface temperature derived from MODIS(2001-2012) and defined a vegetation health index(VHI) based on VCI and TCI for assessing vegetation health condition in the Three Gorges Area, China(TGA). The results of the study show that temporal and spatial characteristics of vegetation health condition can be detected, tracked and mapped by the VHI index. In most parts of the TGA, the vegetation health condition showed an overall increasing trend during the study period, especially in Wulong, Fengdu, Shizhu and other regions located in the midstream sections of the Three Gorges Reservoir. In addition, the four studied vegetation types all showed clear increasing trends during the study period. The increasing trend in the vegetation health condition shows a strong positive correlation with topographical slope and altitude(below 500 m). Over the seasons, this trend is strongest in autumn, followed by spring. However, the correlations between vegetation health condition and climatic factors are more frequently significant in summer and winter than in autumn and spring. The vegetation health condition has been low in 2006 and 2011. This finding is consistent with the extreme weather conditions in those two years. However, only in the summer is vegetation health condition significantly correlated with three climatic factors in most of the study area. This result implies that vegetation growth may show a lagged response to climatic factors and may also be affected by human activities, including agricultural activities, industrial activities and other economic activities.
基金国家自然科学基金面上项目“基于高压人群身心健康的工作环境绿色空间体系研究”(编号51978364)丰田跨学科专项2022“未来城市跨学科研究关键技术集成与示范”(Action Plan for Integrated Demonstration of Key Technologies for Interdisciplinary Research on Future Cities)共同资助。
基金Project(51204074)supported by the National Natural Science Foundation of ChinaProjects(2010009017,201209048,ZX021-201106-031)supported by the National Environmental Protection Public Welfare Industry Targeted Research Fund,China
文摘Soil cadmium(Cd)contamination resulted from mining and smelting is a major environmental concern,and health risk associated with Cd exposure to multi-media through muti-pathway is increasing.Cd concentrations in soils,vegetables and paddy rice were investigated,and potential non-carcinogenic and carcinogenic health risks exposure to Cd were estimated at six villages around the Dabaoshan Mine,South China.A total of 87 soil samples were found to exceed the China's maximum permission level(MPL)for Cd,while the highest value of 4.42 mg/kg was found near irrigation ditch associated with Hengshi River in Xinyi(XY)Village.Cd contents in vegetables and rice exceeded the maximum permissible concentration by more than five times in every village.Cadmium accumulation in plants is in the order of celery>lactuca sativa L>Chinese cabbage>Romaine lettuce>asparagus lettuce>mustard>cabbage mustard>cabbage.The mean hazard quotient(HQ)of all villages is in the range of [5.29,25.75],and the mean values of cancer risk for investigated areas are more than 10 times greater than the USEPA(2009)threshold limit value of 10-4.Moreover,human non-carcinogenic and carcinogenic risks are mainly attributable to paddy rice intake,followed by vegetables intake,soil ingestion,inhalation,and dermal contact.The results indicate that Cd has a huge potential risk on human health for the local residents.
基金supported by the Aeronautical Science Foundation of China(20155553039)the Natural Sciences and Engineering Research Council of Canada(RGPIN 121384-11)
文摘This paper proposes a health evaluation method for degrading systems subject to competing risks of dependent soft and hard failures. To characterize the time-varying degradation rate, the degradation process is determined by a non-stationary Gamma process and the soft failure is encountered when it exceeds a predefined critical level. For the hard failure, a Cox’s proportional hazard model is applied to describe the hazard rate of the time to system failure. The dependent relationship is modeled by incorporating the degradation process as a time-varying covariate into the Cox’s proportional hazard model. To facilitate the health characteristics evaluation, a discretization technique is applied both to the degradation process and the monitoring time.All health characteristics can be obtained in the explicit form using the transition probability matrix, which is computationally attractive for practical applications. Finally, a numerical analysis is carried out to show the effectiveness and the performance of the proposed health evaluation method.
文摘It is well established in experimental animals and Humans that endothelial cells,which cover the luminal surface of all blood vessels,have a pivotal role in the control of vascular homeostasis.The protective effect of endothelial cells is mostly due to their ability to respond to circulating hormones,autacoids,blood-and platelet-derived factors,and also to blood flow by inducing potent vasoprotectivemechanismsincluding predominantlythe formation of nitric oxide(NO),and,often also to some extent,endothelium-derived hyperpolarization,and prostacyclin(PGI2).Besides being a potent vasodilator,NO also effectively prevents platelet activation and has anti-thrombotic and anti-atherosclerotic properties.An endothelial dysfunction characterized by a reduced generation of these endothelium-dependent vasodilator mechanisms associated with vascular oxidative stress and the formation of endothelium-derived contracting factors such as contractile prostanoids is often observed in most types of cardiovascular diseases including hypertension,hypercho⁃lesterolemia,diabetes,and also during physiological ageing in both experimental animals and Humans.Nutrition-derived polyphenols such as those from grapes,tea,cocoa,and berries have been shown to stimulate the endothelial formation of NO by activating the Src/PI3-kinase/Akt-dependent phosphorylation of endothelial NO synthase(eNOS)and to enhance eNOS expression.As a consequence,the active polyphenols will promote a sustained forma⁃tion of NO that contributes to protect the vascular system.Polyphenol-rich products have also been shown to improve an established endothelial dysfunction and to delay the onset of the induction of an endothelial dysfunction in several experimental models of cardiovascular diseases including hypertension and in ageing.Moreover,endothelial senescence characterized by cell cycle arrest and the acquisition of a pro-inflammatory and pro-atherothrombotic phenotype has been identified as an early event promotingthe development of endothelial dysfunc⁃tion.Premature endothelial senescence appears to affect,in particular,arterial sites at risk such as curvatures and bifur⁃cations that are characterized by disturbed flow and low shear stress.The pro-senescent process can be further increased in the presence of a high concentration of glucose,oxidized LDL,and angiotensinⅡ.Anthocyanin-rich products have been shown to accumulate preferentially in senescent endothelial cells,to reduce the expression of cell cycle regulators such as p16,p21 and p53,and to improve the endothelial function.The protective effect is mostly due to their ability to reduce vascular oxidative stress by inhibiting the overexpression of NADPH oxidase and the local angiotensin system.Thus,nutrition-derived polyphenols may be an interesting approach to delay the onset of risk factor-and ageing-related endothelial senescence and dysfunction and,hence,to promote vascular health.
