Understanding the internal structure of Venus promotes the exploration of the evolutionary history of this planet.However,the existing research concerning the internal structure of Venus has not used any inversion met...Understanding the internal structure of Venus promotes the exploration of the evolutionary history of this planet.However,the existing research concerning the internal structure of Venus has not used any inversion methods.In this work we employed an inversion method to determine the internal structure of Venus using observational or hypothetical geodetic data;these data include mass,mean radius,mean moment of inertia and second degree tidal Love number k2.To determine the core state of Venus,we created two models of Venus,an isotropic 3-layer model with entire liquid core and an isotropic 4-layer model with liquid outer core and a solid inner core,assuming that the interior of Venus is spherically symmetric and in hydrostatic equilibrium.A series of the sensitivity analysis of interior structure parameters to the geodetic data considered in here shows that not all of the parameters can be constrained by the geodetic data from Venus.On this basis,a Markov Chain Monte Carlo algorithm was used to determine the posterior probability distribution and the optimal values of the internal structure parameters of Venus with the geodetic data.We found that the 3-layer model is more credible than the 4-layer model via currently geodetic data.For the assumption of the 3-layer model with the k2=0.295±0.066,I/MR^2=0.33±0.0165,andρ=5242.7±2.6 kg m^-3,the liquid iron-rich core of Venus has a radius of 3294+215-261km,which suggests a larger core than previous research has indicated.The average density of the mantle and liquid core of Venus are 4101+325-375and 11885+955-1242kg m~^-3,respectively.展开更多
Porousα-Fe_(2)O_(3) nanowires are synthesized by a simple wet chemical method with a precursor of peroxyacetyl nitrate(PAN),andα-Fe_(2)O_(3) nanoparticles are also synthesized in the same way except for the addition...Porousα-Fe_(2)O_(3) nanowires are synthesized by a simple wet chemical method with a precursor of peroxyacetyl nitrate(PAN),andα-Fe_(2)O_(3) nanoparticles are also synthesized in the same way except for the addition of PAN.Gas sensors are fabricated by coating the samples on ceramic tubes with Au signal electrodes and Ni-Cr heaters.A sensing investigation reveals that the porousα-Fe_(2)O_(3) nanowires have a higher sensitivity compared toα-Fe_(2)O_(3) nanoparticles at 260℃.The corresponding sensor response(R_(a)/R_(g))is 18.2 at the maximum to 100 ppm acetone,and the response and recovery times are about 8 and 12 s,respectively.The porous and one-dimensional nanostructures of the porousα-Fe_(2)O_(3) nanowires benefit for the gas-absorption and electrical-signal-transfer,and thus improve the sensor sensitivity consequentially.展开更多
Background:Several studies have assessed the role of gut microbiota in various cirrhosis etiologies,however,none has done so in the context of Schistosoma joponicum infection in humans.We,therefore,sought to determine...Background:Several studies have assessed the role of gut microbiota in various cirrhosis etiologies,however,none has done so in the context of Schistosoma joponicum infection in humans.We,therefore,sought to determine whether gut microbiota is associated with S.japonicum infection-induced liver cirrhosis.Methods:From December 2017 to November 2019,24 patients with S.joponicum infection-induced liver cirrhosis,as well as 25 age-and sex-matched controls from the Zhejiang Province,China,were enrolled.Fecal samples were collected and used for 16S rRNA gene sequencing(particularly,the hypervariable V4 region)using the lllumina MiSeq system.Wilcoxon Rank-Sum and PERMANOVA tests were used for analysis.展开更多
Citrus rind color is a good indicator of fruit development,and methods to monitor and predict color transformation therefore help the decisions of crop management practices and harvest schedules.This work presents the...Citrus rind color is a good indicator of fruit development,and methods to monitor and predict color transformation therefore help the decisions of crop management practices and harvest schedules.This work presents the complete workflow to predict and visualize citrus color transformation in the orchard featuring high accuracy and fidelity.A total of 107 sample Navel oranges were observed during the color transformation period,resulting in a dataset containing 7,535 citrus images.A framework is proposed that integrates visual saliency into deep learning,and it consists of a segmentation network,a deep mask-guided generative network,and a loss network with manually designed loss functions.Moreover,the fusion of image features and temporal information enables one single model to predict the rind color at different time intervals,thus effectively shrinking the number of model parameters.The semantic segmentation network of the framework achieves the mean intersection over a union score of 0.9694,and the generative network obtains a peak signal-to-noise ratio of 30.01 and a mean local style loss score of 2.710,which indicate both high quality and similarity of the generated images and are also consistent with human perception.To ease the applications in the real world,the model is ported to an Android-based application for mobile devices.The methods can be readily expanded to other fruit crops with a color transformation period.The dataset and the source code are publicly available at GitHub.展开更多
As compared to permanent orthopedic implants for load-bearing applications, biodegradable orthopedic implants have the advantage of no need for removing after healing, but they suffer from the ＂trilemma＂ problem of ...As compared to permanent orthopedic implants for load-bearing applications, biodegradable orthopedic implants have the advantage of no need for removing after healing, but they suffer from the ＂trilemma＂ problem of compromising among sufficiently high mechanical properties, good biocompatibility and proper degradation rate conforming to the growth rate of new bones. In the present work, in vitro and in vivo studies of a Zn-0.05 wt%Mg alloy（namely, Zn-0.05 Mg alloy） were conducted with pure Zn as a control. The Zn-0.05 Mg alloy is composed of a small amount of Mg2 Zn11 phase embedded in the refined Zn matrix with an average grain size of ～20 μm. The addition of 0.05 wt% Mg into Zn significantly increases the ultimate tensile strength up to 225 MPa and the elongation to fracture to 26%, but has little influence on the in vitro degradation rate. Both Zn and Zn-0.05 Mg alloy exhibit homogeneous in vitro degradation with a rate of about 0.15 mm/year. Based on the cytotoxicity evaluation, Zn and Zn-0.05 Mg alloy do not induce toxicity to L-929 cells, indicating that they have little toxicity to the general functions of the animal. An in vivo biocompatibility study of Zn and Zn-0.05 Mg alloy samples by placing them in a rabbit model for 4.12 and 24 weeks, respectively did not show any inflammatory cells, and demonstrated that new bone tissue formed at the bone/implant interface, suggesting that Zn and Zn-0.05 Mg alloy promote the formation of new bone tissue. The in vivo degradation of Zn and Zn-0.05 Mg alloy does not bring harm to the important organs and their cell structures. More interestingly, Zn and Zn-0.05 Mg alloy exhibit strong antibacterial activity against Escherichia coli and Staphylococcus aureus. The above results clearly demonstrate that the Zn-0.05 Mg alloy could be a potential biodegradable orthopedic implant material.展开更多
Explorations for the interior structure of the Moon mainly involve three technologies: the early gravitational observations via circumlunar satellites, the moonquake observations during the Apollo period, and the rece...Explorations for the interior structure of the Moon mainly involve three technologies: the early gravitational observations via circumlunar satellites, the moonquake observations during the Apollo period, and the recent high-resolution remote sensing observations. Based on these technologies, we divided the development of the moon's interior structure into three stages. The first stage is the discovery of high-density anomalous masses(mascons) on the lunar surface with the low-order gravitational field models, which were obtained by observing perturbations of the early lunar orbital satellites. The second stage is the preliminary understanding of the layer structure with the help of moonquake observations during the Apollo period. The third stage is the deep understanding of the structure of the lunar crust, mantle, and core, with the use of high-resolution remote sensing data and the reassessment of moonquake data from the Apollo's mission. This paper gave detailed introduction and comments on different observation technologies, gathered data, and data processing techniques used at the three stages. In addition, this paper analyzed the current issues in the researches on the Moon's internal structure and discussed the prospects for future explorations.展开更多
α-Fe2O3nanotubes was successfully prepared by single nozzle electrospinning method.Scanning electron microscope(SEM)was used to characterize the morphology of-Fe2O3nanotubes.The gas sensing properties of-Fe2O3nanotub...α-Fe2O3nanotubes was successfully prepared by single nozzle electrospinning method.Scanning electron microscope(SEM)was used to characterize the morphology of-Fe2O3nanotubes.The gas sensing properties of-Fe2O3nanotubes were investigated in detail.The results exhibit relatively good sensing properties to acetone at 240°C.The response and recovery times are about 3 and 5 s,respectively.The structure of nanotubes is beneficial to the gas sensing properties,which will enlarge the surface-to-volume ratio of α-Fe2O3and then be available for the transfer of gas,and thus improved the sensor performance consequentially.展开更多
基金the National Natural Science Foundation of China(U1831132,41874010)Innovation Group of Natural Fund of Hubei Province(2018CFA087)+1 种基金the Science and Technology Development Fund of Macao Special Administrative Region(FDCT 007/2016/A1,119/2017/A3,187/2017/A3)Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing(KF201813)。
文摘Understanding the internal structure of Venus promotes the exploration of the evolutionary history of this planet.However,the existing research concerning the internal structure of Venus has not used any inversion methods.In this work we employed an inversion method to determine the internal structure of Venus using observational or hypothetical geodetic data;these data include mass,mean radius,mean moment of inertia and second degree tidal Love number k2.To determine the core state of Venus,we created two models of Venus,an isotropic 3-layer model with entire liquid core and an isotropic 4-layer model with liquid outer core and a solid inner core,assuming that the interior of Venus is spherically symmetric and in hydrostatic equilibrium.A series of the sensitivity analysis of interior structure parameters to the geodetic data considered in here shows that not all of the parameters can be constrained by the geodetic data from Venus.On this basis,a Markov Chain Monte Carlo algorithm was used to determine the posterior probability distribution and the optimal values of the internal structure parameters of Venus with the geodetic data.We found that the 3-layer model is more credible than the 4-layer model via currently geodetic data.For the assumption of the 3-layer model with the k2=0.295±0.066,I/MR^2=0.33±0.0165,andρ=5242.7±2.6 kg m^-3,the liquid iron-rich core of Venus has a radius of 3294+215-261km,which suggests a larger core than previous research has indicated.The average density of the mantle and liquid core of Venus are 4101+325-375and 11885+955-1242kg m~^-3,respectively.
基金Supported by the Jilin Environment Office(No 2009-22),Jilin Provincial Science and Technology Department(No 20100344)the National Innovation Experiment Program for University Students(No 2010C65188).
文摘Porousα-Fe_(2)O_(3) nanowires are synthesized by a simple wet chemical method with a precursor of peroxyacetyl nitrate(PAN),andα-Fe_(2)O_(3) nanoparticles are also synthesized in the same way except for the addition of PAN.Gas sensors are fabricated by coating the samples on ceramic tubes with Au signal electrodes and Ni-Cr heaters.A sensing investigation reveals that the porousα-Fe_(2)O_(3) nanowires have a higher sensitivity compared toα-Fe_(2)O_(3) nanoparticles at 260℃.The corresponding sensor response(R_(a)/R_(g))is 18.2 at the maximum to 100 ppm acetone,and the response and recovery times are about 8 and 12 s,respectively.The porous and one-dimensional nanostructures of the porousα-Fe_(2)O_(3) nanowires benefit for the gas-absorption and electrical-signal-transfer,and thus improve the sensor sensitivity consequentially.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No.XDC06050000)the National Natural Science Foundation of China (Grant No.11972037).
文摘Background:Several studies have assessed the role of gut microbiota in various cirrhosis etiologies,however,none has done so in the context of Schistosoma joponicum infection in humans.We,therefore,sought to determine whether gut microbiota is associated with S.japonicum infection-induced liver cirrhosis.Methods:From December 2017 to November 2019,24 patients with S.joponicum infection-induced liver cirrhosis,as well as 25 age-and sex-matched controls from the Zhejiang Province,China,were enrolled.Fecal samples were collected and used for 16S rRNA gene sequencing(particularly,the hypervariable V4 region)using the lllumina MiSeq system.Wilcoxon Rank-Sum and PERMANOVA tests were used for analysis.
基金supported by the Fundamental Research Funds for the Central Universities of China(2662020LXQD002 and 2662022YJ005)the Knowledge Innovation Program of Wuhan-Shuguang Project(2022010801020234)the Key Laboratory of Biomedical Engineering of Hainan Province(2022003).
文摘Citrus rind color is a good indicator of fruit development,and methods to monitor and predict color transformation therefore help the decisions of crop management practices and harvest schedules.This work presents the complete workflow to predict and visualize citrus color transformation in the orchard featuring high accuracy and fidelity.A total of 107 sample Navel oranges were observed during the color transformation period,resulting in a dataset containing 7,535 citrus images.A framework is proposed that integrates visual saliency into deep learning,and it consists of a segmentation network,a deep mask-guided generative network,and a loss network with manually designed loss functions.Moreover,the fusion of image features and temporal information enables one single model to predict the rind color at different time intervals,thus effectively shrinking the number of model parameters.The semantic segmentation network of the framework achieves the mean intersection over a union score of 0.9694,and the generative network obtains a peak signal-to-noise ratio of 30.01 and a mean local style loss score of 2.710,which indicate both high quality and similarity of the generated images and are also consistent with human perception.To ease the applications in the real world,the model is ported to an Android-based application for mobile devices.The methods can be readily expanded to other fruit crops with a color transformation period.The dataset and the source code are publicly available at GitHub.
基金financially supported by the National Natural Science Foundation of China (Nos. 51525101 and 81271995)Fundamental Research Funds for the Central Universities (No. N141008001)
文摘As compared to permanent orthopedic implants for load-bearing applications, biodegradable orthopedic implants have the advantage of no need for removing after healing, but they suffer from the ＂trilemma＂ problem of compromising among sufficiently high mechanical properties, good biocompatibility and proper degradation rate conforming to the growth rate of new bones. In the present work, in vitro and in vivo studies of a Zn-0.05 wt%Mg alloy（namely, Zn-0.05 Mg alloy） were conducted with pure Zn as a control. The Zn-0.05 Mg alloy is composed of a small amount of Mg2 Zn11 phase embedded in the refined Zn matrix with an average grain size of ～20 μm. The addition of 0.05 wt% Mg into Zn significantly increases the ultimate tensile strength up to 225 MPa and the elongation to fracture to 26%, but has little influence on the in vitro degradation rate. Both Zn and Zn-0.05 Mg alloy exhibit homogeneous in vitro degradation with a rate of about 0.15 mm/year. Based on the cytotoxicity evaluation, Zn and Zn-0.05 Mg alloy do not induce toxicity to L-929 cells, indicating that they have little toxicity to the general functions of the animal. An in vivo biocompatibility study of Zn and Zn-0.05 Mg alloy samples by placing them in a rabbit model for 4.12 and 24 weeks, respectively did not show any inflammatory cells, and demonstrated that new bone tissue formed at the bone/implant interface, suggesting that Zn and Zn-0.05 Mg alloy promote the formation of new bone tissue. The in vivo degradation of Zn and Zn-0.05 Mg alloy does not bring harm to the important organs and their cell structures. More interestingly, Zn and Zn-0.05 Mg alloy exhibit strong antibacterial activity against Escherichia coli and Staphylococcus aureus. The above results clearly demonstrate that the Zn-0.05 Mg alloy could be a potential biodegradable orthopedic implant material.
基金supported in part by the National Natural Science Foundation of China (Grant Nos. 41604004, 41374024)the Hubei Province Natural Science Foundation Innovation Group Project (Grant No. 2015CFA011)
文摘Explorations for the interior structure of the Moon mainly involve three technologies: the early gravitational observations via circumlunar satellites, the moonquake observations during the Apollo period, and the recent high-resolution remote sensing observations. Based on these technologies, we divided the development of the moon's interior structure into three stages. The first stage is the discovery of high-density anomalous masses(mascons) on the lunar surface with the low-order gravitational field models, which were obtained by observing perturbations of the early lunar orbital satellites. The second stage is the preliminary understanding of the layer structure with the help of moonquake observations during the Apollo period. The third stage is the deep understanding of the structure of the lunar crust, mantle, and core, with the use of high-resolution remote sensing data and the reassessment of moonquake data from the Apollo's mission. This paper gave detailed introduction and comments on different observation technologies, gathered data, and data processing techniques used at the three stages. In addition, this paper analyzed the current issues in the researches on the Moon's internal structure and discussed the prospects for future explorations.
基金supported by the Jilin Environment Office(2009-22)Jilin Provincial Science and Technology Department(20100344)the National Innovation Experiment Program for University Students(2010C65188)
文摘α-Fe2O3nanotubes was successfully prepared by single nozzle electrospinning method.Scanning electron microscope(SEM)was used to characterize the morphology of-Fe2O3nanotubes.The gas sensing properties of-Fe2O3nanotubes were investigated in detail.The results exhibit relatively good sensing properties to acetone at 240°C.The response and recovery times are about 3 and 5 s,respectively.The structure of nanotubes is beneficial to the gas sensing properties,which will enlarge the surface-to-volume ratio of α-Fe2O3and then be available for the transfer of gas,and thus improved the sensor performance consequentially.
