With the advancement of modern science and technology, large scientific facilities are increasingly oriented toward demand and application, and can be used for basic research as well as serving multiple disciplines. D...With the advancement of modern science and technology, large scientific facilities are increasingly oriented toward demand and application, and can be used for basic research as well as serving multiple disciplines. Developing large scientific facilities and related analytical technologies enhances understanding of large scientific facilities and popularizes their application in research across multiple disciplines. The combination of light or neutron sources from large scientific facilities and advanced analytical technologies can be achieved for materials structure information, dynamics study of chemical reactions, high dissociation of biomolecules, 3D visualization of energy materials or biological samples, etc. We first introduce the progress of domestic large scientific facilities of synchrotron radiation(SR) and free electron lasers(FELs) with different wavelengths and neutron sources.We further discuss the comparison between Chinese and typical foreign facilities in X-ray radiation from X-ray tubes, synchrotrons, X-ray FELs, and neutron sources based on physical parameters of light and neutron sources. In addition, we focus on the technological progress and perspectives combined with advanced X-ray radiation and neutron sources of large scientific facilities in China, especially in the nanoscience fields of energy catalysis and biological science. We hope that this roadmap will provide references on technology and methods to experimental users, as well as prospects for future development of technologies based on large research infrastructure facilities. Comprehensive studies and guidelines for basic research to practical application in various disciplines can be made with the assistance of large scientific facilities.展开更多
AIM:To develop protocols for isolation of exosomes and characterization of their RNA content.METHODS:Exosomes were extracted from He La cell culture media and human blood serum using the Total exosome isolation(from c...AIM:To develop protocols for isolation of exosomes and characterization of their RNA content.METHODS:Exosomes were extracted from He La cell culture media and human blood serum using the Total exosome isolation(from cell culture media)reagent,and Total exosome isolation(from serum)reagent respectively.Identity and purity of the exosomes was confirmed by Nanosight?analysis,electron microscopy,and Western blots for CD63 marker.Exosomal RNA cargo was recovered with the Total exosome RNA and protein isolation kit.Finally,RNA was profiled using Bioanalyzer and quantitative reverse transcriptionpolymerase chain reaction(q RT-PCR)methodology.RESULTS:Here we describe a novel approach for robust and scalable isolation of exosomes from cell culture media and serum,with subsequent isolation and analysis of RNA residing within these vesicles.The isolation procedure is completed in a fraction of the time,compared to the current standard protocols utilizing ultracentrifugation,and allows to recover fully intact exosomes in higher yields.Exosomes were found tocontain a very diverse RNA cargo,primarily short sequences 20-200 nt(such as mi RNA and fragments of m RNA),however longer RNA species were detected as well,including full-length 18S and 28S r RNA.CONCLUSION:We have successfully developed a set of reagents and a workflow allowing fast and efficient extraction of exosomes,followed by isolation of RNA and its analysis by q RT-PCR and other techniques.展开更多
Wild soybean is a typical short-day plant that begins flowering when the days are shorter than its critical photoperiod, Soybean was domesticated in the temperate region of East Asia at the relatively high latitude, a...Wild soybean is a typical short-day plant that begins flowering when the days are shorter than its critical photoperiod, Soybean was domesticated in the temperate region of East Asia at the relatively high latitude, and the breeding and release of soybean varieties have historically centered on mid- and high-latitude temperate regions. Low-latitude areas with tropical and sub- tropical climates were previously considered unsuitable for soy- bean production because most temperate soybean varieties ex- hibited precocious flowering and early maturity and suffered from low yields.展开更多
OBJECTIVE To study the relationship between bFGF gene expression and proliferative activity in meningiomas. METHODS Thirty-seven samples of meningioma were examed using Northern hybridization for bFGF-gene expression ...OBJECTIVE To study the relationship between bFGF gene expression and proliferative activity in meningiomas. METHODS Thirty-seven samples of meningioma were examed using Northern hybridization for bFGF-gene expression and immunohistochemi- stry for bFGF protein expression and the Ki-67LI. RESULTS bFGF mRNA was detected in 22 meningiomas of Grade Ⅰ and in all samples of Grade Ⅱ and Ⅲ. Six of the Grade Ⅰ tumors were negative, giving an overall positive rate of 83.8 % for bFGF mRNA. Autoradiography was conducted using a thin scaning apparatus, bFGF mRNA expression compared to that for β-actin was 0.34±0.06 for Grade Ⅰ tumors compared to 0.82±0.12 for Grade Ⅱ and Ⅲ tumors. The difference was highly significant （P〈0.001）. The results of immunohistochemistry showed that the number of the positive cells for the bFGF protein was 29.7±7.6% in Grade Ⅰ tumors and 63.2±11.7 % in Grade Ⅱ plus Ⅲ, resulting in a significant difference between them （P〈0.001） . The Ki-67LI was found to be 2.8±1.1% in Grade Ⅰ and 6.5±1.3 % in Grade Ⅱ plus Ⅲ. The former was significantly lower than the later （P〈0.001）. CONCLUSION The expression of bFGF was correlated well with the malignancy of the meningiomas.展开更多
RRT^(*)(rapidly-exploring random tree star)算法是机械臂路径规划中的一个重要工具,但在高维空间内的应用表现存在搜索效率低下、对维数的敏感度高、难以快速收敛至优化路径等问题。此外机械臂避障的规划需要考虑到路径的平滑性,但...RRT^(*)(rapidly-exploring random tree star)算法是机械臂路径规划中的一个重要工具,但在高维空间内的应用表现存在搜索效率低下、对维数的敏感度高、难以快速收敛至优化路径等问题。此外机械臂避障的规划需要考虑到路径的平滑性,但是算法生成的路径往往缺乏所需的平滑性,难以直接应用于实际的机械臂操作。针对这些问题,研究提出了一个基于贪心策略的RRT^(*)算法改进版本。新算法改进了代价函数和重连策略,并在高维搜索环境中,通过贪心算法进行偏执采样,自适应地选取预设路径节点,从而提高搜索效率,增强轨迹的平滑性并进行直接应用。通过Matlab、ROS仿真和机械臂实际应用避障实验,验证了改进的RRT^(*)算法在三维空间中的高效性和优越性,尤其是在搜索效率与路径平滑性等方面。展开更多
Heavy metal(loid)s contamination is a constant issue at smelting sites.It is essential to investigate the spatial distribution and migration characteristics of heavy metal(loid)s in the soil for environmental manageme...Heavy metal(loid)s contamination is a constant issue at smelting sites.It is essential to investigate the spatial distribution and migration characteristics of heavy metal(loid)s in the soil for environmental management and remediation strategies of non-ferrous smelting sites.In this study,203 soil samples from 57 sites were collected in a typical lead smelting site.The findings demonstrated that there were significant Pb,Zn,Cd,and As contamination in soil samples.The spatial distribution of heavy metal(loid)s showed strong spatial heterogeneity,the contaminated soil areas of Pb,As,Cd,and Zn were 99.5%,98.9%,85.3%,and 72.4%,respectively.Pb,Cd,and As contamination of the soil reached a depth of 5 m,which migrated from the surface to deep soil layers.The leaching contents of Zn,Pb,and As decreased obviously in 3-4 m soil layer,but the leaching content of Cd was still high,which indicated the high migration of Cd.With the increase of depth,the proportion of acid soluble fraction of heavy metal(loid)s decreased,and the residual fraction increased.The acid soluble fraction of Cd accounted for a higher proportion,and As mainly existed in reducible and residual fractions in soil.According to the calculation of the migration factor,the migration of heavy metal(loid)s in soils were ordered as Cd>Zn>Pb>As.The outcomes are advantageous for risk reduction and site remediation for non-ferrous metal smelting sites.展开更多
A general prediction model for seven heavy metals was established using the heavy metal contents of 207soil samples measured by a portable X-ray fluorescence spectrometer(XRF)and six environmental factors as model cor...A general prediction model for seven heavy metals was established using the heavy metal contents of 207soil samples measured by a portable X-ray fluorescence spectrometer(XRF)and six environmental factors as model correction coefficients.The eXtreme Gradient Boosting(XGBoost)model was used to fit the relationship between the content of heavy metals and environment characteristics to evaluate the soil ecological risk of the smelting site.The results demonstrated that the generalized prediction model developed for Pb,Cd,and As was highly accurate with fitted coefficients(R^(2))values of 0.911,0.950,and 0.835,respectively.Topsoil presented the highest ecological risk,and there existed high potential ecological risk at some positions with different depths due to high mobility of Cd.Generally,the application of machine learning significantly increased the accuracy of pXRF measurements,and identified key environmental factors.The adapted potential ecological risk assessment emphasized the need to focus on Pb,Cd,and As in future site remediation efforts.展开更多
Facial beauty analysis is an important topic in human society.It may be used as a guidance for face beautification applications such as cosmetic surgery.Deep neural networks(DNNs)have recently been adopted for facial ...Facial beauty analysis is an important topic in human society.It may be used as a guidance for face beautification applications such as cosmetic surgery.Deep neural networks(DNNs)have recently been adopted for facial beauty analysis and have achieved remarkable performance.However,most existing DNN-based models regard facial beauty analysis as a normal classification task.They ignore important prior knowledge in traditional machine learning models which illustrate the significant contribution of the geometric features in facial beauty analysis.To be specific,landmarks of the whole face and facial organs are introduced to extract geometric features to make the decision.Inspired by this,we introduce a novel dual-branch network for facial beauty analysis:one branch takes the Swin Transformer as the backbone to model the full face and global patterns,and another branch focuses on the masked facial organs with the residual network to model the local patterns of certain facial parts.Additionally,the designed multi-scale feature fusion module can further facilitate our network to learn complementary semantic information between the two branches.In model optimisation,we propose a hybrid loss function,where especially geometric regulation is introduced by regressing the facial landmarks and it can force the extracted features to convey facial geometric features.Experiments performed on the SCUT-FBP5500 dataset and the SCUT-FBP dataset demonstrate that our model outperforms the state-of-the-art convolutional neural networks models,which proves the effectiveness of the proposed geometric regularisation and dual-branch structure with the hybrid network.To the best of our knowledge,this is the first study to introduce a Vision Transformer into the facial beauty analysis task.展开更多
基金supported by the National Basic Research Program of China (2022YFA1603701, 2021YFA1200900)the institutionalized scientific research platform relies on Beijing Synchrotron Radiation Facility of Chinese Academy of Sciences,the Strategic Priority Research Program of Chinese Academy of Sciences (XDB36000000)+2 种基金the National Natural Science Foundation of China (22027810, 82341044,22388101 and 22307028)the CAMS Innovation Fund for Medical Sciences(CIFMS 2019-I2M-5-018)the New Cornerstone Science Foundation。
文摘With the advancement of modern science and technology, large scientific facilities are increasingly oriented toward demand and application, and can be used for basic research as well as serving multiple disciplines. Developing large scientific facilities and related analytical technologies enhances understanding of large scientific facilities and popularizes their application in research across multiple disciplines. The combination of light or neutron sources from large scientific facilities and advanced analytical technologies can be achieved for materials structure information, dynamics study of chemical reactions, high dissociation of biomolecules, 3D visualization of energy materials or biological samples, etc. We first introduce the progress of domestic large scientific facilities of synchrotron radiation(SR) and free electron lasers(FELs) with different wavelengths and neutron sources.We further discuss the comparison between Chinese and typical foreign facilities in X-ray radiation from X-ray tubes, synchrotrons, X-ray FELs, and neutron sources based on physical parameters of light and neutron sources. In addition, we focus on the technological progress and perspectives combined with advanced X-ray radiation and neutron sources of large scientific facilities in China, especially in the nanoscience fields of energy catalysis and biological science. We hope that this roadmap will provide references on technology and methods to experimental users, as well as prospects for future development of technologies based on large research infrastructure facilities. Comprehensive studies and guidelines for basic research to practical application in various disciplines can be made with the assistance of large scientific facilities.
文摘AIM:To develop protocols for isolation of exosomes and characterization of their RNA content.METHODS:Exosomes were extracted from He La cell culture media and human blood serum using the Total exosome isolation(from cell culture media)reagent,and Total exosome isolation(from serum)reagent respectively.Identity and purity of the exosomes was confirmed by Nanosight?analysis,electron microscopy,and Western blots for CD63 marker.Exosomal RNA cargo was recovered with the Total exosome RNA and protein isolation kit.Finally,RNA was profiled using Bioanalyzer and quantitative reverse transcriptionpolymerase chain reaction(q RT-PCR)methodology.RESULTS:Here we describe a novel approach for robust and scalable isolation of exosomes from cell culture media and serum,with subsequent isolation and analysis of RNA residing within these vesicles.The isolation procedure is completed in a fraction of the time,compared to the current standard protocols utilizing ultracentrifugation,and allows to recover fully intact exosomes in higher yields.Exosomes were found tocontain a very diverse RNA cargo,primarily short sequences 20-200 nt(such as mi RNA and fragments of m RNA),however longer RNA species were detected as well,including full-length 18S and 28S r RNA.CONCLUSION:We have successfully developed a set of reagents and a workflow allowing fast and efficient extraction of exosomes,followed by isolation of RNA and its analysis by q RT-PCR and other techniques.
文摘Wild soybean is a typical short-day plant that begins flowering when the days are shorter than its critical photoperiod, Soybean was domesticated in the temperate region of East Asia at the relatively high latitude, and the breeding and release of soybean varieties have historically centered on mid- and high-latitude temperate regions. Low-latitude areas with tropical and sub- tropical climates were previously considered unsuitable for soy- bean production because most temperate soybean varieties ex- hibited precocious flowering and early maturity and suffered from low yields.
文摘OBJECTIVE To study the relationship between bFGF gene expression and proliferative activity in meningiomas. METHODS Thirty-seven samples of meningioma were examed using Northern hybridization for bFGF-gene expression and immunohistochemi- stry for bFGF protein expression and the Ki-67LI. RESULTS bFGF mRNA was detected in 22 meningiomas of Grade Ⅰ and in all samples of Grade Ⅱ and Ⅲ. Six of the Grade Ⅰ tumors were negative, giving an overall positive rate of 83.8 % for bFGF mRNA. Autoradiography was conducted using a thin scaning apparatus, bFGF mRNA expression compared to that for β-actin was 0.34±0.06 for Grade Ⅰ tumors compared to 0.82±0.12 for Grade Ⅱ and Ⅲ tumors. The difference was highly significant （P〈0.001）. The results of immunohistochemistry showed that the number of the positive cells for the bFGF protein was 29.7±7.6% in Grade Ⅰ tumors and 63.2±11.7 % in Grade Ⅱ plus Ⅲ, resulting in a significant difference between them （P〈0.001） . The Ki-67LI was found to be 2.8±1.1% in Grade Ⅰ and 6.5±1.3 % in Grade Ⅱ plus Ⅲ. The former was significantly lower than the later （P〈0.001）. CONCLUSION The expression of bFGF was correlated well with the malignancy of the meningiomas.
文摘RRT^(*)(rapidly-exploring random tree star)算法是机械臂路径规划中的一个重要工具,但在高维空间内的应用表现存在搜索效率低下、对维数的敏感度高、难以快速收敛至优化路径等问题。此外机械臂避障的规划需要考虑到路径的平滑性,但是算法生成的路径往往缺乏所需的平滑性,难以直接应用于实际的机械臂操作。针对这些问题,研究提出了一个基于贪心策略的RRT^(*)算法改进版本。新算法改进了代价函数和重连策略,并在高维搜索环境中,通过贪心算法进行偏执采样,自适应地选取预设路径节点,从而提高搜索效率,增强轨迹的平滑性并进行直接应用。通过Matlab、ROS仿真和机械臂实际应用避障实验,验证了改进的RRT^(*)算法在三维空间中的高效性和优越性,尤其是在搜索效率与路径平滑性等方面。
基金supported by the National Key Research and Development Program of China (No.2019YFC1803604)the National Natural Science Foundation of China (No.42177392).
文摘Heavy metal(loid)s contamination is a constant issue at smelting sites.It is essential to investigate the spatial distribution and migration characteristics of heavy metal(loid)s in the soil for environmental management and remediation strategies of non-ferrous smelting sites.In this study,203 soil samples from 57 sites were collected in a typical lead smelting site.The findings demonstrated that there were significant Pb,Zn,Cd,and As contamination in soil samples.The spatial distribution of heavy metal(loid)s showed strong spatial heterogeneity,the contaminated soil areas of Pb,As,Cd,and Zn were 99.5%,98.9%,85.3%,and 72.4%,respectively.Pb,Cd,and As contamination of the soil reached a depth of 5 m,which migrated from the surface to deep soil layers.The leaching contents of Zn,Pb,and As decreased obviously in 3-4 m soil layer,but the leaching content of Cd was still high,which indicated the high migration of Cd.With the increase of depth,the proportion of acid soluble fraction of heavy metal(loid)s decreased,and the residual fraction increased.The acid soluble fraction of Cd accounted for a higher proportion,and As mainly existed in reducible and residual fractions in soil.According to the calculation of the migration factor,the migration of heavy metal(loid)s in soils were ordered as Cd>Zn>Pb>As.The outcomes are advantageous for risk reduction and site remediation for non-ferrous metal smelting sites.
基金financially supported from the National Key Research and Development Program of China(No.2019YFC1803601)the Fundamental Research Funds for the Central Universities of Central South University,China(No.2023ZZTS0801)+1 种基金the Postgraduate Innovative Project of Central South University,China(No.2023XQLH068)the Postgraduate Scientific Research Innovation Project of Hunan Province,China(No.QL20230054)。
文摘A general prediction model for seven heavy metals was established using the heavy metal contents of 207soil samples measured by a portable X-ray fluorescence spectrometer(XRF)and six environmental factors as model correction coefficients.The eXtreme Gradient Boosting(XGBoost)model was used to fit the relationship between the content of heavy metals and environment characteristics to evaluate the soil ecological risk of the smelting site.The results demonstrated that the generalized prediction model developed for Pb,Cd,and As was highly accurate with fitted coefficients(R^(2))values of 0.911,0.950,and 0.835,respectively.Topsoil presented the highest ecological risk,and there existed high potential ecological risk at some positions with different depths due to high mobility of Cd.Generally,the application of machine learning significantly increased the accuracy of pXRF measurements,and identified key environmental factors.The adapted potential ecological risk assessment emphasized the need to focus on Pb,Cd,and As in future site remediation efforts.
基金Shenzhen Science and Technology Program,Grant/Award Number:ZDSYS20211021111415025Shenzhen Institute of Artificial Intelligence and Robotics for SocietyYouth Science and Technology Talents Development Project of Guizhou Education Department,Grant/Award Number:QianJiaoheKYZi[2018]459。
文摘Facial beauty analysis is an important topic in human society.It may be used as a guidance for face beautification applications such as cosmetic surgery.Deep neural networks(DNNs)have recently been adopted for facial beauty analysis and have achieved remarkable performance.However,most existing DNN-based models regard facial beauty analysis as a normal classification task.They ignore important prior knowledge in traditional machine learning models which illustrate the significant contribution of the geometric features in facial beauty analysis.To be specific,landmarks of the whole face and facial organs are introduced to extract geometric features to make the decision.Inspired by this,we introduce a novel dual-branch network for facial beauty analysis:one branch takes the Swin Transformer as the backbone to model the full face and global patterns,and another branch focuses on the masked facial organs with the residual network to model the local patterns of certain facial parts.Additionally,the designed multi-scale feature fusion module can further facilitate our network to learn complementary semantic information between the two branches.In model optimisation,we propose a hybrid loss function,where especially geometric regulation is introduced by regressing the facial landmarks and it can force the extracted features to convey facial geometric features.Experiments performed on the SCUT-FBP5500 dataset and the SCUT-FBP dataset demonstrate that our model outperforms the state-of-the-art convolutional neural networks models,which proves the effectiveness of the proposed geometric regularisation and dual-branch structure with the hybrid network.To the best of our knowledge,this is the first study to introduce a Vision Transformer into the facial beauty analysis task.
