Ambient ozone(O3)exposure may be associated with a reduction of semen quality,yet the potential biological mechanisms remain unclear.We investigated the effects of certain seminal plasma metabolites on mediating the l...Ambient ozone(O3)exposure may be associated with a reduction of semen quality,yet the potential biological mechanisms remain unclear.We investigated the effects of certain seminal plasma metabolites on mediating the links between O3 exposure and the deterioration of semen quality.The untargeted metabolomics analysis was performed on semen samples of 200 Chinese adult men to determine candidate metabolites associated with characteristics of semen quality.Mediation analysis was adopted to examine whether these metabolites modulated the links between O3 exposure and semen quality.We found a significant reduction in sperm concentration by−28.1%(95%CI:−41.7%,−11.3%),and sperm count by−29.2%(95%CI:−43.7%,−11.0%)associated with each 10μg/m3 increase in ambient O3 concentration during the period of sperm development.We delineated 7 metabolites in seminal fluid that substantially mediated the links between O3 exposure and declined semen quality,including myristoleic acid,aspartyl-isoleucine,phenylethyl primeveroside,ACar(18:2),ACar(18:1),FAHFA(22:6/22:3),and LPS(22:5).Among these,myristoleic acid exhibited the most pronounced mediation effects,with its indirect effect of which accounts for 46.4%of the overall association.Our findings suggested that exposure to ozone decreased sperm quality by disrupting fatty acid metabolism,particularly myristoleic acid.展开更多
Different configurations for the monochroma-tor crystals and the analyzer crystals have been used in hard X-ray diffraction enhanced imaging (DEI) methods to over-come the complex task to adjust each of them to the id...Different configurations for the monochroma-tor crystals and the analyzer crystals have been used in hard X-ray diffraction enhanced imaging (DEI) methods to over-come the complex task to adjust each of them to the ideal position. Here we present a very compact DEI configuration, and preliminary results of experiments performed at the Beijing Synchrotron Radiation Facility (BSRF) using only two crystals: the first one acting as monochromator and the second one as analyzer in the Bragg geometry. Refraction contrast images characterized by high contrast and spatial resolution are obtained and compared with absorption im-ages. Differences among these images will be outlined and discussed emphasizing the potential capabilities of this very simple layout that guarantees a high transmission efficiency.展开更多
What is already known about this topic?The proportion of elderly living alone in China is approximately 10%.Living away from family poses enormous challenges for older adults.What is added by this report?Compared to t...What is already known about this topic?The proportion of elderly living alone in China is approximately 10%.Living away from family poses enormous challenges for older adults.What is added by this report?Compared to those living with family,elderly individuals living alone exhibit a lower registration rate with general practitioners and have less social support.What are the implications for public health practice?While the current health service system for elderly people living alone is working relatively well,there is a need for additional programs to enhance social support and improve their social well-being.展开更多
Fullerene derivatives are highly attractive materials in solar cells,organic thermoelectrics,and other devices.However,the intrinsic low electron mobility and electrical conductivity restrict their potential device pe...Fullerene derivatives are highly attractive materials in solar cells,organic thermoelectrics,and other devices.However,the intrinsic low electron mobility and electrical conductivity restrict their potential device performance,such as perovskite solar cells(PSCs).Herein,we successfully enhanced the electric properties and morphology of phenyl-C61-butyric acid methyl ester(PCBM)by n-doping it with a benzimidazoline derivative,9-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)-julolidine(JLBI-H)via a solution process.We found the n-doping can not only improve the conductivity and optimize the band alignment but also enable the PCBM to have a constantly strong charge extraction ability in a wide temperature from 173 to 373 K,which guarantees a stable photovoltaic performance of the corresponding PSCs under a wide range of operating temperatures.With the JLBI-H-doped PCBM,we improved the efficiency from 17.9%to 19.8%,along with enhanced stability of the nonencapsulated devices following the aging protocol of ISOS-D-1.展开更多
Droplets of Ag60Sb34Cu6 ternary alloy within the diameter range of 60—800 μm were rapidly solidified by means of drop tube containerless processing, and the solidi- fication mechanism is analyzed. With a decrease in...Droplets of Ag60Sb34Cu6 ternary alloy within the diameter range of 60—800 μm were rapidly solidified by means of drop tube containerless processing, and the solidi- fication mechanism is analyzed. With a decrease in droplet size, the cooling rate increases from 57 to 5.8×104 K/s. The maximum undercooling is determined to be 180 K (0.23TL) and the microstructure of primary ε(Ag3Sb) dendrite refines drastically until homogenous equiaxed dendrite forms. Ex- perimental results indicate that (ε+Ag) pseudobinary eutectic cannot form under high undercooling conditions and the solubility of Ag in primary ε phase increases as undercooling increases. Based on thermal analysis and crystal growth morphology, it is found that this alloy is solidified in two ways corresponding to different undercooling levels.展开更多
Wavelength-selective thermal emitters(WS-TEs)have been frequently designed to achieve desired target emissivity spectra,as a typical emissivity engineering,for broad applications such as thermal camouflage,radiative c...Wavelength-selective thermal emitters(WS-TEs)have been frequently designed to achieve desired target emissivity spectra,as a typical emissivity engineering,for broad applications such as thermal camouflage,radiative cooling,and gas sensing,etc.However,previous designs require prior knowledge of materials or structures for different applications and the designed WS-TEs usually vary from applications to applications in terms of materials and structures,thus lacking of a general design framework for emissivity engineering across different applications.Moreover,previous designs fail to tackle the simultaneous design of both materials and structures,as they either fix materials to design structures or fix structures to select suitable materials.Herein,we employ the deep Q-learning network algorithm,a reinforcement learning method based on deep learning framework,to design multilayer WS-TEs.To demonstrate the general validity,three WS-TEs are designed for various applications,including thermal camouflage,radiative cooling and gas sensing,which are then fabricated and measured.The merits of the deep Q-learning algorithm include that it can(1)offer a general design framework for WS-TEs beyond one-dimensional multilayer structures;(2)autonomously select suitable materials from a self-built material library and(3)autonomously optimize structural parameters for the target emissivity spectra.The present framework is demonstrated to be feasible and efficient in designing WS-TEs across different applications,and the design parameters are highly scalable in materials,structures,dimensions,and the target functions,offering a general framework for emissivity engineering and paving the way for efficient design of nonlinear optimization problems beyond thermal metamaterials.展开更多
Phononic crystals(PnCs)have had a multiple of important and promising applications such as sonic diodes,acoustic cloaking,optomechanic,and thermoelectrics[1–5].Undoubtably,it is of significance to explore new finding...Phononic crystals(PnCs)have had a multiple of important and promising applications such as sonic diodes,acoustic cloaking,optomechanic,and thermoelectrics[1–5].Undoubtably,it is of significance to explore new findings for PnCs,which can open new application opportunities.展开更多
To the Editor:Nonalcoholic fatty liver disease(NAFLD)is one of the most common chronic liver diseases globally,and this systemic disease carries a substantial economic burden and will result in a greater disease burde...To the Editor:Nonalcoholic fatty liver disease(NAFLD)is one of the most common chronic liver diseases globally,and this systemic disease carries a substantial economic burden and will result in a greater disease burden in the future.[1]Mass screening of asymptomatic individuals using ultrasonography is not cost-effective.Therefore,simple,noninvasive tests are required to identify patients with NAFLD.The fatty liver index(FLI)and hepatic steatosis index(HSI)are accurate and easy to obtain.展开更多
A traditional and typical listening course at college level can be described in terms of three steps: press button-check answers- repress button. It has been believed that the teaching of listening comprehension cente...A traditional and typical listening course at college level can be described in terms of three steps: press button-check answers- repress button. It has been believed that the teaching of listening comprehension centers on what teachers do, that is, the actions and behaviors which teachers carry out in classroom are given prominence. Students. are seen as展开更多
A novel aqueous Sn-S complex solution was applied as precursor to fabricate SnO2 electron selective layers (ESLs) for the hybrid perovskite solar cells (PSCs).The tin and sulfur powder were directly dissolved in a (NH...A novel aqueous Sn-S complex solution was applied as precursor to fabricate SnO2 electron selective layers (ESLs) for the hybrid perovskite solar cells (PSCs).The tin and sulfur powder were directly dissolved in a (NH4)2S water solution to form Sn-S precursor.After depositon and annealing,the SnO2 film was formed,presenting as a low cost and enviromental friendly method for preparation of ESL.The films showed excellent transmittance at visible wavelength range.Moreover,the method exhibited high compatibility for doping using Cu,Cd,Li,and Zn elements.Zn doping (0.05 M) in the as-prepared SnO2 ESL significantly improved perovskite solar cells (PSCs) performance.The highest PCE of 13.17% was achived with 15% enhancement compared to that of undoped SnO2 ESL samples.TiCl4 modifications on SnO2 film improved photovoltaic performance to 14.45%,but resulted in the poor long-term stability,around 80% more degredation than that of PSCs based on Zn-doped SnO2 films.展开更多
The ISM band at 2.4 GHz has mostly been used or planned for indoor systems.This band is also attractive for outdoor systems owing to the ease of the system deployment, as nofrequency licenses are required. In this pap...The ISM band at 2.4 GHz has mostly been used or planned for indoor systems.This band is also attractive for outdoor systems owing to the ease of the system deployment, as nofrequency licenses are required. In this paper, a multiple successive internal multireflection modelis used to estimate the complex electric permittivity at 2.4 GHz band. To obtain the data,measurements are performed at 160 MHz bandwidth centered about 2. 4 GHz using a vector networkanalyzer, which provides information about the amplitude and phase of transmission coefficient.Several samples of each material are measured and the results vary from sample to sample. It hasalso been found that some obstacles have polarization behaviour.展开更多
The survival probability of super heavy nuclei produced in cold fusion reactions is studied by using the standard Fermi gas level density formula and analyzed with fission and neutron evaporation characteristics predi...The survival probability of super heavy nuclei produced in cold fusion reactions is studied by using the standard Fermi gas level density formula and analyzed with fission and neutron evaporation characteristics predicted in different theoretical models. The level density formula used in this letter suppresses the ratio of neutron emission width to fission width, Гn/Гf. The dependence of Гn/Гf on the saddle point level density parameter and excitation energy is also investigated.展开更多
In DNS model, a key point is the calculation of PES because it governs the fusion dynamics and thus determines the optimum excitation energy of the compound nucleus and the optimum bombarding energy. Furthermore, it g...In DNS model, a key point is the calculation of PES because it governs the fusion dynamics and thus determines the optimum excitation energy of the compound nucleus and the optimum bombarding energy. Furthermore, it gives the information about the optimum projectile-target combination leading to a certain super-heavy nucleus.展开更多
The survival probability of the excited compound nucleus is considered as one of the crucial factors for producing SHE. The competition between the neutron emission and the fission during the de-excitation process is ...The survival probability of the excited compound nucleus is considered as one of the crucial factors for producing SHE. The competition between the neutron emission and the fission during the de-excitation process is the main mechanism to determine the survival probability. The form of level density formula, the level展开更多
文摘Ambient ozone(O3)exposure may be associated with a reduction of semen quality,yet the potential biological mechanisms remain unclear.We investigated the effects of certain seminal plasma metabolites on mediating the links between O3 exposure and the deterioration of semen quality.The untargeted metabolomics analysis was performed on semen samples of 200 Chinese adult men to determine candidate metabolites associated with characteristics of semen quality.Mediation analysis was adopted to examine whether these metabolites modulated the links between O3 exposure and semen quality.We found a significant reduction in sperm concentration by−28.1%(95%CI:−41.7%,−11.3%),and sperm count by−29.2%(95%CI:−43.7%,−11.0%)associated with each 10μg/m3 increase in ambient O3 concentration during the period of sperm development.We delineated 7 metabolites in seminal fluid that substantially mediated the links between O3 exposure and declined semen quality,including myristoleic acid,aspartyl-isoleucine,phenylethyl primeveroside,ACar(18:2),ACar(18:1),FAHFA(22:6/22:3),and LPS(22:5).Among these,myristoleic acid exhibited the most pronounced mediation effects,with its indirect effect of which accounts for 46.4%of the overall association.Our findings suggested that exposure to ozone decreased sperm quality by disrupting fatty acid metabolism,particularly myristoleic acid.
文摘Different configurations for the monochroma-tor crystals and the analyzer crystals have been used in hard X-ray diffraction enhanced imaging (DEI) methods to over-come the complex task to adjust each of them to the ideal position. Here we present a very compact DEI configuration, and preliminary results of experiments performed at the Beijing Synchrotron Radiation Facility (BSRF) using only two crystals: the first one acting as monochromator and the second one as analyzer in the Bragg geometry. Refraction contrast images characterized by high contrast and spatial resolution are obtained and compared with absorption im-ages. Differences among these images will be outlined and discussed emphasizing the potential capabilities of this very simple layout that guarantees a high transmission efficiency.
基金support from community health service centers in Xicheng and Daxing Districts,Beijingsupport from Provincial Center for Disease Control and Prevention in Zhejiang+1 种基金Provincial Patriotic Health and Health Promotion Center in JiangxiProvincial Health Education Center in Chongqing,Liaoning and Gansu.
文摘What is already known about this topic?The proportion of elderly living alone in China is approximately 10%.Living away from family poses enormous challenges for older adults.What is added by this report?Compared to those living with family,elderly individuals living alone exhibit a lower registration rate with general practitioners and have less social support.What are the implications for public health practice?While the current health service system for elderly people living alone is working relatively well,there is a need for additional programs to enhance social support and improve their social well-being.
基金National Key Research and Development Plan,Grant/Award Number:2019YFE0107200National Natural Science Foundation of China,Grant/Award Numbers:22075221,52002302,91963209+4 种基金Key Research and Development Project of Shanxi Province,Grant/Award Number:202202060301003Hubei Provincial Natural Science Foundation of China,Grant/Award Number:2022CFB1000Knowledge Innovation Program of Wuhan-Shuguang Project,Grant/Award Number:2023010201020367State Key Laboratory of Advanced Technology for Materials Synthesis and Processing(Wuhan University of Technology),Grant/Award Number:2022-KF-17Basic Science Research Program through the National Research Foundation of Korea(NRF),funded by the Ministry of Science,ICT,and Future Planning,Grant/Award Numbers:2019K1A3A1A61091347,2021M3H4A1A02051234。
文摘Fullerene derivatives are highly attractive materials in solar cells,organic thermoelectrics,and other devices.However,the intrinsic low electron mobility and electrical conductivity restrict their potential device performance,such as perovskite solar cells(PSCs).Herein,we successfully enhanced the electric properties and morphology of phenyl-C61-butyric acid methyl ester(PCBM)by n-doping it with a benzimidazoline derivative,9-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)-julolidine(JLBI-H)via a solution process.We found the n-doping can not only improve the conductivity and optimize the band alignment but also enable the PCBM to have a constantly strong charge extraction ability in a wide temperature from 173 to 373 K,which guarantees a stable photovoltaic performance of the corresponding PSCs under a wide range of operating temperatures.With the JLBI-H-doped PCBM,we improved the efficiency from 17.9%to 19.8%,along with enhanced stability of the nonencapsulated devices following the aging protocol of ISOS-D-1.
文摘Droplets of Ag60Sb34Cu6 ternary alloy within the diameter range of 60—800 μm were rapidly solidified by means of drop tube containerless processing, and the solidi- fication mechanism is analyzed. With a decrease in droplet size, the cooling rate increases from 57 to 5.8×104 K/s. The maximum undercooling is determined to be 180 K (0.23TL) and the microstructure of primary ε(Ag3Sb) dendrite refines drastically until homogenous equiaxed dendrite forms. Ex- perimental results indicate that (ε+Ag) pseudobinary eutectic cannot form under high undercooling conditions and the solubility of Ag in primary ε phase increases as undercooling increases. Based on thermal analysis and crystal growth morphology, it is found that this alloy is solidified in two ways corresponding to different undercooling levels.
基金support by National Natural Science Foundation of China(52211540005,52076087,52161160332)Natural Science Foundation of Hubei Province(2023AFA072)+3 种基金the Open Project Program of Wuhan National Laboratory for Optoelectronics(2021WNLOKF004)Wuhan City Science and Technology Program(2020010601012197)Knowledge Innovation Shuguang Program.W.L.acknowledges the financial support from Key Research and Development plan of Hubei Province(2021BGE037)J.S.acknowledges the financial support from JSPS Bilateral Joint Research Projects(120227404).
文摘Wavelength-selective thermal emitters(WS-TEs)have been frequently designed to achieve desired target emissivity spectra,as a typical emissivity engineering,for broad applications such as thermal camouflage,radiative cooling,and gas sensing,etc.However,previous designs require prior knowledge of materials or structures for different applications and the designed WS-TEs usually vary from applications to applications in terms of materials and structures,thus lacking of a general design framework for emissivity engineering across different applications.Moreover,previous designs fail to tackle the simultaneous design of both materials and structures,as they either fix materials to design structures or fix structures to select suitable materials.Herein,we employ the deep Q-learning network algorithm,a reinforcement learning method based on deep learning framework,to design multilayer WS-TEs.To demonstrate the general validity,three WS-TEs are designed for various applications,including thermal camouflage,radiative cooling and gas sensing,which are then fabricated and measured.The merits of the deep Q-learning algorithm include that it can(1)offer a general design framework for WS-TEs beyond one-dimensional multilayer structures;(2)autonomously select suitable materials from a self-built material library and(3)autonomously optimize structural parameters for the target emissivity spectra.The present framework is demonstrated to be feasible and efficient in designing WS-TEs across different applications,and the design parameters are highly scalable in materials,structures,dimensions,and the target functions,offering a general framework for emissivity engineering and paving the way for efficient design of nonlinear optimization problems beyond thermal metamaterials.
文摘Phononic crystals(PnCs)have had a multiple of important and promising applications such as sonic diodes,acoustic cloaking,optomechanic,and thermoelectrics[1–5].Undoubtably,it is of significance to explore new findings for PnCs,which can open new application opportunities.
文摘To the Editor:Nonalcoholic fatty liver disease(NAFLD)is one of the most common chronic liver diseases globally,and this systemic disease carries a substantial economic burden and will result in a greater disease burden in the future.[1]Mass screening of asymptomatic individuals using ultrasonography is not cost-effective.Therefore,simple,noninvasive tests are required to identify patients with NAFLD.The fatty liver index(FLI)and hepatic steatosis index(HSI)are accurate and easy to obtain.
文摘A traditional and typical listening course at college level can be described in terms of three steps: press button-check answers- repress button. It has been believed that the teaching of listening comprehension centers on what teachers do, that is, the actions and behaviors which teachers carry out in classroom are given prominence. Students. are seen as
基金the National Key Research and Development Plan(2017YFE0131900)the Hubei Provincial Natural Science Foundation of China(2016CFB464)+2 种基金the Fundamental Research Funds for the Central Universities(WUT:2016IVA089,2016III030)the Hubei Key Laboratory of Low Dimensional Optoelectronic Material and Devices(HLOM151002)“Chutian Scholar Program”of Hubei Province,China。
文摘A novel aqueous Sn-S complex solution was applied as precursor to fabricate SnO2 electron selective layers (ESLs) for the hybrid perovskite solar cells (PSCs).The tin and sulfur powder were directly dissolved in a (NH4)2S water solution to form Sn-S precursor.After depositon and annealing,the SnO2 film was formed,presenting as a low cost and enviromental friendly method for preparation of ESL.The films showed excellent transmittance at visible wavelength range.Moreover,the method exhibited high compatibility for doping using Cu,Cd,Li,and Zn elements.Zn doping (0.05 M) in the as-prepared SnO2 ESL significantly improved perovskite solar cells (PSCs) performance.The highest PCE of 13.17% was achived with 15% enhancement compared to that of undoped SnO2 ESL samples.TiCl4 modifications on SnO2 film improved photovoltaic performance to 14.45%,but resulted in the poor long-term stability,around 80% more degredation than that of PSCs based on Zn-doped SnO2 films.
文摘The ISM band at 2.4 GHz has mostly been used or planned for indoor systems.This band is also attractive for outdoor systems owing to the ease of the system deployment, as nofrequency licenses are required. In this paper, a multiple successive internal multireflection modelis used to estimate the complex electric permittivity at 2.4 GHz band. To obtain the data,measurements are performed at 160 MHz bandwidth centered about 2. 4 GHz using a vector networkanalyzer, which provides information about the amplitude and phase of transmission coefficient.Several samples of each material are measured and the results vary from sample to sample. It hasalso been found that some obstacles have polarization behaviour.
文摘The survival probability of super heavy nuclei produced in cold fusion reactions is studied by using the standard Fermi gas level density formula and analyzed with fission and neutron evaporation characteristics predicted in different theoretical models. The level density formula used in this letter suppresses the ratio of neutron emission width to fission width, Гn/Гf. The dependence of Гn/Гf on the saddle point level density parameter and excitation energy is also investigated.
文摘In DNS model, a key point is the calculation of PES because it governs the fusion dynamics and thus determines the optimum excitation energy of the compound nucleus and the optimum bombarding energy. Furthermore, it gives the information about the optimum projectile-target combination leading to a certain super-heavy nucleus.
文摘The survival probability of the excited compound nucleus is considered as one of the crucial factors for producing SHE. The competition between the neutron emission and the fission during the de-excitation process is the main mechanism to determine the survival probability. The form of level density formula, the level
