Stable carbon and oxygen isotopes have been observed in dinosaur eggshell samples, identified asMacroolithus yaotunensis, collected in two sections of the Nanxiong Basin, Guangdong Province, South China. Multiple posi...Stable carbon and oxygen isotopes have been observed in dinosaur eggshell samples, identified asMacroolithus yaotunensis, collected in two sections of the Nanxiong Basin, Guangdong Province, South China. Multiple positive δ18O perturbations that occurred during the K/T transition of about 150 ka suggest that there may have been at least three periods of the extreme dry climate with a mean annual air temperature over 27δC. δ13C ranges from -8.37% to -11.60% of the dinosaur eggshells, added to the metabolic enrichment of 16%, may indicate that the dinosaurs represented by this type of eggshells probably consumed the plant species of C3 type with the δ13C values of -24.3%— -27.6‰ Moreover, the trend toward more negative δ13C values of the eggshells during the K/T transition could be an indirect consequence of a lasting increase in atmospheric CO2 concentration.展开更多
In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluste...In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluster analysis, hyper-parameter test and other models, and SPSS, Python and other tools were used to obtain the classification rules of glass products under different fluxes, sub classification under different chemical compositions, hyper-parameter K value test and rationality analysis. Research can provide theoretical support for the protection and restoration of ancient glass relics.展开更多
For current service-oriented applications, individual web service usually cannot meet the requirements arising from real world applications, so it is necessary to combine the functionalities of different web services ...For current service-oriented applications, individual web service usually cannot meet the requirements arising from real world applications, so it is necessary to combine the functionalities of different web services to obtain a composite service in response to users＇ service requests. In order to address the problem of web service composition, this paper proposes an efficient approach to composing basic services in case no any individual service can fully satisfy users＇ requests. Compared with the general strategies adopted in most previously proposed approaches where only the best composition solution is produced, the QoS-aware service composition approach is given and top k solutions in the framework are provided, rather than focusing on obtaining the best composition solution, since the presented approach allows more candidates that are likely to meet the requirements of the users. The approach is based on a succinct binary tree data structure, and a system,named ATC （Approach to Top-k Composite services retrieval） system is implemented. In ATC, Qos is taken into account for composite service, and a heuristic-based search method is proposed to retrieve top k composite service. Some extensive experiments are designed and two web service benchmarks are used for performance study. The experimental results snow that the proposed approach can assure high precision and efficiency for composite service search.展开更多
Protein succinylation is a biochemical reaction in which a succinyl group(-CO-CH2-CH2-CO-)is attached to the lysine residue of a protein molecule.Lysine succinylation plays important regulatory roles in living cells.H...Protein succinylation is a biochemical reaction in which a succinyl group(-CO-CH2-CH2-CO-)is attached to the lysine residue of a protein molecule.Lysine succinylation plays important regulatory roles in living cells.However,studies in this field are limited by the difficulty in experimentally identifying the substrate site specificity of lysine succinylation.To facilitate this process,several tools have been proposed for the computational identification of succinylated lysine sites.In this study,we developed an approach to investigate the substrate specificity of lysine succinylated sites based on amino acid composition.Using experimentally verified lysine succinylated sites collected from public resources,the significant differences in position-specific amino acid composition between succinylated and non-succinylated sites were represented using the Two Sample Logo program.These findings enabled the adoption of an effective machine learning method,support vector machine,to train a predictive model with not only the amino acid composition,but also the composition of k-spaced amino acid pairs.After the selection of the best model using a ten-fold crossvalidation approach,the selected model significantly outperformed existing tools based on an independent dataset manually extracted from published research articles.Finally,the selected model was used to develop a web-based tool,SuccSite,to aid the study of protein succinylation.Two proteins were used as case studies on the website to demonstrate the effective prediction of succinylation sites.We will regularly update SuccSite by integrating more experimental datasets.SuccSite is freely accessible at http://csb.cse.yzu.edu.tw/SuccSite/.展开更多
The results from comparative study of the EUF-K values of four different soils and of their varions particlefractions (<2μm, 2-10μm and 10 50μm) showed that the EUF-K values were related to the composition ofcl...The results from comparative study of the EUF-K values of four different soils and of their varions particlefractions (<2μm, 2-10μm and 10 50μm) showed that the EUF-K values were related to the composition ofclay minerals and the soil particle size. The EUF-K values (0-35 min) were closely related to the amountof rapidly available K and part of non-exchangeable K of soils. Biological experiments proved that EUFtechnique was an effective method for evaluating soil K-supplying power.展开更多
Panax japonicus and its approximation varieties,such as Rhizoma Panacis Majoris and Panax japonicus C. A. Mey. var.major （Burk.） C.Y. Wu et K.M. Feng belong to Panax,which are less commonly used traditional Chinese ...Panax japonicus and its approximation varieties,such as Rhizoma Panacis Majoris and Panax japonicus C. A. Mey. var.major （Burk.） C.Y. Wu et K.M. Feng belong to Panax,which are less commonly used traditional Chinese medicine. Because of similar traits and effectiveness,they were always used as one type of medicine for a long time. Aiming at this phenomenon,the chemical composition and contents of P. japonicus and its approximation varieties from different area were compared in order to provide a chemical basis for clarifying the classification of the genus.展开更多
文摘Stable carbon and oxygen isotopes have been observed in dinosaur eggshell samples, identified asMacroolithus yaotunensis, collected in two sections of the Nanxiong Basin, Guangdong Province, South China. Multiple positive δ18O perturbations that occurred during the K/T transition of about 150 ka suggest that there may have been at least three periods of the extreme dry climate with a mean annual air temperature over 27δC. δ13C ranges from -8.37% to -11.60% of the dinosaur eggshells, added to the metabolic enrichment of 16%, may indicate that the dinosaurs represented by this type of eggshells probably consumed the plant species of C3 type with the δ13C values of -24.3%— -27.6‰ Moreover, the trend toward more negative δ13C values of the eggshells during the K/T transition could be an indirect consequence of a lasting increase in atmospheric CO2 concentration.
文摘In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluster analysis, hyper-parameter test and other models, and SPSS, Python and other tools were used to obtain the classification rules of glass products under different fluxes, sub classification under different chemical compositions, hyper-parameter K value test and rationality analysis. Research can provide theoretical support for the protection and restoration of ancient glass relics.
文摘For current service-oriented applications, individual web service usually cannot meet the requirements arising from real world applications, so it is necessary to combine the functionalities of different web services to obtain a composite service in response to users＇ service requests. In order to address the problem of web service composition, this paper proposes an efficient approach to composing basic services in case no any individual service can fully satisfy users＇ requests. Compared with the general strategies adopted in most previously proposed approaches where only the best composition solution is produced, the QoS-aware service composition approach is given and top k solutions in the framework are provided, rather than focusing on obtaining the best composition solution, since the presented approach allows more candidates that are likely to meet the requirements of the users. The approach is based on a succinct binary tree data structure, and a system,named ATC （Approach to Top-k Composite services retrieval） system is implemented. In ATC, Qos is taken into account for composite service, and a heuristic-based search method is proposed to retrieve top k composite service. Some extensive experiments are designed and two web service benchmarks are used for performance study. The experimental results snow that the proposed approach can assure high precision and efficiency for composite service search.
基金the Warshel Institute for Computational Biology,School of Life and Health Sciences,The Chinese University of Hong Kong,Shenzhen,China for financially supporting this research
文摘Protein succinylation is a biochemical reaction in which a succinyl group(-CO-CH2-CH2-CO-)is attached to the lysine residue of a protein molecule.Lysine succinylation plays important regulatory roles in living cells.However,studies in this field are limited by the difficulty in experimentally identifying the substrate site specificity of lysine succinylation.To facilitate this process,several tools have been proposed for the computational identification of succinylated lysine sites.In this study,we developed an approach to investigate the substrate specificity of lysine succinylated sites based on amino acid composition.Using experimentally verified lysine succinylated sites collected from public resources,the significant differences in position-specific amino acid composition between succinylated and non-succinylated sites were represented using the Two Sample Logo program.These findings enabled the adoption of an effective machine learning method,support vector machine,to train a predictive model with not only the amino acid composition,but also the composition of k-spaced amino acid pairs.After the selection of the best model using a ten-fold crossvalidation approach,the selected model significantly outperformed existing tools based on an independent dataset manually extracted from published research articles.Finally,the selected model was used to develop a web-based tool,SuccSite,to aid the study of protein succinylation.Two proteins were used as case studies on the website to demonstrate the effective prediction of succinylation sites.We will regularly update SuccSite by integrating more experimental datasets.SuccSite is freely accessible at http://csb.cse.yzu.edu.tw/SuccSite/.
文摘The results from comparative study of the EUF-K values of four different soils and of their varions particlefractions (<2μm, 2-10μm and 10 50μm) showed that the EUF-K values were related to the composition ofclay minerals and the soil particle size. The EUF-K values (0-35 min) were closely related to the amountof rapidly available K and part of non-exchangeable K of soils. Biological experiments proved that EUFtechnique was an effective method for evaluating soil K-supplying power.
基金Supported by the National Natural Foundation of China(30873383)~~
文摘Panax japonicus and its approximation varieties,such as Rhizoma Panacis Majoris and Panax japonicus C. A. Mey. var.major （Burk.） C.Y. Wu et K.M. Feng belong to Panax,which are less commonly used traditional Chinese medicine. Because of similar traits and effectiveness,they were always used as one type of medicine for a long time. Aiming at this phenomenon,the chemical composition and contents of P. japonicus and its approximation varieties from different area were compared in order to provide a chemical basis for clarifying the classification of the genus.
