Background Depression,anxiety and schizophrenia among older persons have become global public health challenges.However,the burden of these disorders in ageing and aged countries has not been analysed.Aims To investig...Background Depression,anxiety and schizophrenia among older persons have become global public health challenges.However,the burden of these disorders in ageing and aged countries has not been analysed.Aims To investigate the burden of depression,anxiety and schizophrenia among older adults in ageing and aged countries.Methods Using data from the Global Burden of Disease Study 2019,we calculated the estimated annual percentage change(EAPC)in the age-standardised incidence rates(ASiR)and age-standardised disability-adjusted life years(DALYs)rates(ASDR)for depression,anxiety and schizophrenia of older people in ageing countries(China,India,Indonesia)and aged countries(Japan,Italy,Portugal)between 1990 and 2019.Trends in incidence and DALYs were analysed by gender and age.Results In 2019,the highest incidence of depression,anxiety and schizophrenia in the older population in aged countries was in Japan(927271.3(752552.3-1125796.5),51498.2(37625.7-70487.3)and 126.0(61.0-223.2),respectively),while the highest incidence in ageing countries was in China(5797556.9(4599403.4-7133006.5),330256.1(246448.9-445987.4)and 1067.7(556.2-1775.9),respectively).DALYs for these disorders were similar,with the highest in Japan and China.From 1990 to 2019,the ASIR for depressive disorders decreased in aged countries but increased in ageing countries;the ASIR for anxiety disorders and schizophrenia declined in both ageing and aged countries.The ASDR for depressive disorders was consistent with the ASIR but not for anxiety disorders and schizophrenia.The ASIR for depressive disorders was higher in older women,while the opposite was observed in anxiety disorders and schizophrenia.Notably,the conditions of burden of depressive disorders,anxiety disorders and schizophrenia in the 65-70-year-old age group were the most burdensome.Conclusions The incidence and DALYs of these three mental disorders increased while exhibiting differences between ageing and aged countries.Raising awareness about formulating health policies for preventing and treating mental disorders in the older population is necessary to reduce the future burden posed by the ageing challenge.展开更多
The safety and reliability of weapon systems would be significantly affected by changes in the performance of energetic materials due to ambient temperature and humidity.Nanothermites have promising applications due t...The safety and reliability of weapon systems would be significantly affected by changes in the performance of energetic materials due to ambient temperature and humidity.Nanothermites have promising applications due to their excellent reactivity.Therefore it becomes extremely important to understand their aging and failure process in the environment before using them.Here,the aging and failure process of Al/CuO in 71°C/60%RH were investigated,and showed that CuO nanoparticles negatively catalyze Al nanopowders,resulting in rapid hydration.The anti-aging effect of FAS-17-coated Al nanopowder was also examined.The aging process of Al,Al/CuO,and Al@FAS-17/CuO in high humidity and heat environment were revealed by quasi-in situ SEM and TEM methods.Compared with the aging of pure Al,the Al nanopowder in the nanothermites strongly agglomerated with the CuO nanopowder and hydrated earlier.This may be caused by CuO catalyzed hydration of Al nanopowder.The energy release experiments showed that the performance of Al/CuO decreased rapidly and failed to ignite after 4 h of aging.In contrast,the Al@FAS-17/CuO thermite can achieve long-term stability of up to 60 h in the same environment by simple cladding of FAS-17.It is found that FAS-17 coated Al nanopowder can prevent both particle agglomeration and water erosion,which is an effective means to make nanothermites application in high humidity and heat environment.展开更多
This research considered the effect of non-natural aging on the microstructural characteristics and mechanical properties of as-cast aluminum 6063 alloys. The samples were developed through a sand casting process and ...This research considered the effect of non-natural aging on the microstructural characteristics and mechanical properties of as-cast aluminum 6063 alloys. The samples were developed through a sand casting process and machined into tensile and impact test samples before carrying out solution heat treatment at 550?C (0.83 T<sub>m</sub>) on two parts of the samples while retaining one part as the control. The two parts were further divided into sets denoted A and B and were aged at 180?C (0.27 T<sub>m</sub>) and 160?C (0.24 T<sub>m</sub>), respectively, for 12 hours. The results showed that sample A has the optimal yield strength and ultimate tensile strength of 192 and 206 MPa, respectively. Likewise, the sample gave the highest impact strength value of about 9.63 J/mm<sup>2</sup>. The observed results were supported by the optical micrograph, which revealed that the sample has evenly dispersed precipitates in its microstructure. This is deemed responsible for the observed increase in strength of the sample.展开更多
Cerium oxide/silicon rubber was prepared via mechanical blending.Mechanical and frictional properties,as well as thermal stability after thermo-oxidative ageing were investigated in this rubber composite.3D surface pr...Cerium oxide/silicon rubber was prepared via mechanical blending.Mechanical and frictional properties,as well as thermal stability after thermo-oxidative ageing were investigated in this rubber composite.3D surface profilometry,scanning electron microscopy(SEM)and thermogravimetry analysis(TGA)were used to study the friction surface characteristics,friction mechanism and thermal stability,respectively.Additionally,swelling experiments were carried out to investigate the variation of crosslinking density.After thermo-oxidative ageing,the tear strength of cerium oxide/silicon rubber decreases.However,in the early ageing stage,improvements in tensile strength,elongation at break,and frictional performance are caused by crosslinking density increments.Moreover,the addition of cerium oxide remarkably improves the re-cross linking degree during ageing process,which in turn decreases the number of holes on the friction surface and endows the silicon rubber with better mechanical and frictional properties,as well as thermo-oxidative ageing resistance.展开更多
This study investigated the characteristics of wood fiber/polycaprolactone composite after an artificial accelerated thermo-oxidative aging treatment.The effect of time,temperature and humidity during the treatment on...This study investigated the characteristics of wood fiber/polycaprolactone composite after an artificial accelerated thermo-oxidative aging treatment.The effect of time,temperature and humidity during the treatment on their mechanical,chemical and morphology properties were evaluated.The composite was prepared from melted wood fibers and modified polycaprolactone by a molding process.A temperature and humidity controllable test chamber was used for the thermo-oxidative aging of the composite.The thermo-oxidative aging caused surface of the composite to be much more rougher and even a few cracks and holes appeared on it.According to the spectra of Fourier Transform Infrared(FTIR)and Gel Permeation Chromatography(GPC),C=O in the molecular chain of polycaprolactone was hydrolyzed and C–O was broken after the aging treatment,which resulted in a reduction in average molecular weight of the composite.Moreover,results showed that the mechanical strength decreased a lot with the increase in time,temperature and humidity,and the effect of temperature and humidity was more significant compared with that of time.Controlling the temperature and humidity during thermo-oxidative aging treatment could accelerate the aging of composite,which provided a quick and effective method for evaluating the aging resistance of the composite.展开更多
基金Shanghai'Science and Technology Innovation Action Plan'medical innovation research(21Y11905600)Shanghai'Science and Technology Innovation Action Plan'Natural Science Foundation of Shanghai(21ZR1455100)+1 种基金the National Natural Science Foundation of China(81701344)the Shanghai Mental Health Center General Projects(2021-YJ-02).
文摘Background Depression,anxiety and schizophrenia among older persons have become global public health challenges.However,the burden of these disorders in ageing and aged countries has not been analysed.Aims To investigate the burden of depression,anxiety and schizophrenia among older adults in ageing and aged countries.Methods Using data from the Global Burden of Disease Study 2019,we calculated the estimated annual percentage change(EAPC)in the age-standardised incidence rates(ASiR)and age-standardised disability-adjusted life years(DALYs)rates(ASDR)for depression,anxiety and schizophrenia of older people in ageing countries(China,India,Indonesia)and aged countries(Japan,Italy,Portugal)between 1990 and 2019.Trends in incidence and DALYs were analysed by gender and age.Results In 2019,the highest incidence of depression,anxiety and schizophrenia in the older population in aged countries was in Japan(927271.3(752552.3-1125796.5),51498.2(37625.7-70487.3)and 126.0(61.0-223.2),respectively),while the highest incidence in ageing countries was in China(5797556.9(4599403.4-7133006.5),330256.1(246448.9-445987.4)and 1067.7(556.2-1775.9),respectively).DALYs for these disorders were similar,with the highest in Japan and China.From 1990 to 2019,the ASIR for depressive disorders decreased in aged countries but increased in ageing countries;the ASIR for anxiety disorders and schizophrenia declined in both ageing and aged countries.The ASDR for depressive disorders was consistent with the ASIR but not for anxiety disorders and schizophrenia.The ASIR for depressive disorders was higher in older women,while the opposite was observed in anxiety disorders and schizophrenia.Notably,the conditions of burden of depressive disorders,anxiety disorders and schizophrenia in the 65-70-year-old age group were the most burdensome.Conclusions The incidence and DALYs of these three mental disorders increased while exhibiting differences between ageing and aged countries.Raising awareness about formulating health policies for preventing and treating mental disorders in the older population is necessary to reduce the future burden posed by the ageing challenge.
基金supported by the National Natural Science Foundation of China(Grant No.22275092)。
文摘The safety and reliability of weapon systems would be significantly affected by changes in the performance of energetic materials due to ambient temperature and humidity.Nanothermites have promising applications due to their excellent reactivity.Therefore it becomes extremely important to understand their aging and failure process in the environment before using them.Here,the aging and failure process of Al/CuO in 71°C/60%RH were investigated,and showed that CuO nanoparticles negatively catalyze Al nanopowders,resulting in rapid hydration.The anti-aging effect of FAS-17-coated Al nanopowder was also examined.The aging process of Al,Al/CuO,and Al@FAS-17/CuO in high humidity and heat environment were revealed by quasi-in situ SEM and TEM methods.Compared with the aging of pure Al,the Al nanopowder in the nanothermites strongly agglomerated with the CuO nanopowder and hydrated earlier.This may be caused by CuO catalyzed hydration of Al nanopowder.The energy release experiments showed that the performance of Al/CuO decreased rapidly and failed to ignite after 4 h of aging.In contrast,the Al@FAS-17/CuO thermite can achieve long-term stability of up to 60 h in the same environment by simple cladding of FAS-17.It is found that FAS-17 coated Al nanopowder can prevent both particle agglomeration and water erosion,which is an effective means to make nanothermites application in high humidity and heat environment.
文摘This research considered the effect of non-natural aging on the microstructural characteristics and mechanical properties of as-cast aluminum 6063 alloys. The samples were developed through a sand casting process and machined into tensile and impact test samples before carrying out solution heat treatment at 550?C (0.83 T<sub>m</sub>) on two parts of the samples while retaining one part as the control. The two parts were further divided into sets denoted A and B and were aged at 180?C (0.27 T<sub>m</sub>) and 160?C (0.24 T<sub>m</sub>), respectively, for 12 hours. The results showed that sample A has the optimal yield strength and ultimate tensile strength of 192 and 206 MPa, respectively. Likewise, the sample gave the highest impact strength value of about 9.63 J/mm<sup>2</sup>. The observed results were supported by the optical micrograph, which revealed that the sample has evenly dispersed precipitates in its microstructure. This is deemed responsible for the observed increase in strength of the sample.
基金Project supported by the Development Plan for Academics in Huanshui,the Natural Science Foundation of the Henan Province(182300410169,182102210201)the Support Project of Scientific and Technological Innovation Talents of Universities in Henan Province(19HASTIT023).
文摘Cerium oxide/silicon rubber was prepared via mechanical blending.Mechanical and frictional properties,as well as thermal stability after thermo-oxidative ageing were investigated in this rubber composite.3D surface profilometry,scanning electron microscopy(SEM)and thermogravimetry analysis(TGA)were used to study the friction surface characteristics,friction mechanism and thermal stability,respectively.Additionally,swelling experiments were carried out to investigate the variation of crosslinking density.After thermo-oxidative ageing,the tear strength of cerium oxide/silicon rubber decreases.However,in the early ageing stage,improvements in tensile strength,elongation at break,and frictional performance are caused by crosslinking density increments.Moreover,the addition of cerium oxide remarkably improves the re-cross linking degree during ageing process,which in turn decreases the number of holes on the friction surface and endows the silicon rubber with better mechanical and frictional properties,as well as thermo-oxidative ageing resistance.
基金The work was supported by National Key R&D Plan Project(2017YFD0601200)Hunan Key R&D Plan Project(2017SK2334)of College of Materials Science and Engineering,Central South University of Forestry and Technology.
文摘This study investigated the characteristics of wood fiber/polycaprolactone composite after an artificial accelerated thermo-oxidative aging treatment.The effect of time,temperature and humidity during the treatment on their mechanical,chemical and morphology properties were evaluated.The composite was prepared from melted wood fibers and modified polycaprolactone by a molding process.A temperature and humidity controllable test chamber was used for the thermo-oxidative aging of the composite.The thermo-oxidative aging caused surface of the composite to be much more rougher and even a few cracks and holes appeared on it.According to the spectra of Fourier Transform Infrared(FTIR)and Gel Permeation Chromatography(GPC),C=O in the molecular chain of polycaprolactone was hydrolyzed and C–O was broken after the aging treatment,which resulted in a reduction in average molecular weight of the composite.Moreover,results showed that the mechanical strength decreased a lot with the increase in time,temperature and humidity,and the effect of temperature and humidity was more significant compared with that of time.Controlling the temperature and humidity during thermo-oxidative aging treatment could accelerate the aging of composite,which provided a quick and effective method for evaluating the aging resistance of the composite.
