In this study, the entire mitochondrial DNA(mtDNA) control region(CR) of Pholis fangi was amplified via polymerase chain reaction followed by direct sequencing. The length of the mtDNA CR consensus sequence of P. fang...In this study, the entire mitochondrial DNA(mtDNA) control region(CR) of Pholis fangi was amplified via polymerase chain reaction followed by direct sequencing. The length of the mtDNA CR consensus sequence of P. fangi was 853 bp in length. In accordance with the recognition sites as were previously reported in fish species, the mtDNA CR sequence of P. fangi can be divided into 3 domains, i.e., the extended terminal associated sequence(ETAS), the central conserved sequence block(CSB), and the CSB domain. In addition, the following structures were identified in the mtDNA CR sequence of P. fangi: 2 ETASs in the ETAS domain(TAS and cTAS), 6 CSBs in the central CSB domain(CSB-F to CSB-A), and 3 CSBs in the CSB domain(CSB-1 to CSB-3). These demonstrated that the structure of the mtDNA CR of P. fangi was substantially different from those of most other fish species. The mtDNA CR sequence of P. fangi contained one conserved region from 656 bp to 815 bp. Similar to most other fish species, P. fangi has no tandem repeat sequences in its mtDNA CR sequence. Phylogenetic analysis based on the complete mtDNA CR sequences showed that there were no genetic differences within P. fangi populations of the same geographical origin and between P. fangi populations of different geographical origins.展开更多
Now environment is an important topic in academic field.Many researches focus on the negative outcomes of nature which are being continually created by human and much attention has been paid to how the environment is ...Now environment is an important topic in academic field.Many researches focus on the negative outcomes of nature which are being continually created by human and much attention has been paid to how the environment is protected through integrated research,movement and policy.But few studies are concentrated on population and environment and are to find out the interconnectivity and underlying mechanism that have an effect on people's preferring additional children and perception to environment.Many researchers claim that population growth is a great problem for environment but they do not provide the indepth integrated knowledge and mechanism that influence fertility trend and environmental problems.It is very crucial to develop practical and concrete initiatives to confirm a transition to reduce population growth and redirect the perception on population and environment.展开更多
An optimal maintenance policy tor deteriorating components based on quasi renew-process model is presented. In this policy, the first N - 1 failures of a component are maintained by repairs and the N'h failure is mai...An optimal maintenance policy tor deteriorating components based on quasi renew-process model is presented. In this policy, the first N - 1 failures of a component are maintained by repairs and the N'h failure is maintained by replacement. The policy takes replacement actions at component lev- el by considering the fact that more and more components are designed to be field replaceable and maintenance activities are setting free from system halt. Concerning system structure impact, impor- tance measure is employed in the optimization procedure which aims at maximizing the long-rnn prof- it per unit time. Two example series parallel systems are taken to illustrate the policy and it is proved to work well. According to importance analysis, components are classified into important ones and unimportant ones based on the system behavior under their failures. Simulation results show that the presented policy makes a clear distinction between them and takes effective mainte- nance actions to compensate the deteriorating of components.展开更多
为了解决海量数据分析中的非凸状等复杂聚类问题,同时兼顾聚类算法运算速度,提出了一种新的基于竞争思想的快速分级聚类算法.首先,根据给定邻域半径对数据进行第1级分类;然后,在第1级聚类的基础上,基于数据竞争的思想,以簇间数据密度为...为了解决海量数据分析中的非凸状等复杂聚类问题,同时兼顾聚类算法运算速度,提出了一种新的基于竞争思想的快速分级聚类算法.首先,根据给定邻域半径对数据进行第1级分类;然后,在第1级聚类的基础上,基于数据竞争的思想,以簇间数据密度为依据,设立第1级聚类生成的小簇之间小簇联系性权重的增加准则;最后,依据该准则计算有联系的小簇之间联系权重,对达到权重阈值的小簇进行合并,从而解决非凸状等复杂聚类问题.仿真实验表明,算法的聚类精度和抗噪声能力均优于传统的K-means算法和基于密度的DBSCAN(densitybased spatial clustering of applications with noise)算法.由于算法复杂度较低,算法对于大数据的聚类分析将会具有更好的适用性.展开更多
Contamination of the food chain with heavy metals is considered as one of the major environmental pathways of human exposure to metals leading to potential health risks. This study aimed to investigate the concentrati...Contamination of the food chain with heavy metals is considered as one of the major environmental pathways of human exposure to metals leading to potential health risks. This study aimed to investigate the concentrations of heavy metals such as copper (Cu), zinc (Zn), chromium (Cr), nickel (Ni), and manganese (Mn) in agricultural soils and food crops (fruit, leaf, and root vegetables), and their associated health risks to the local population in selected southern districts of Khyber Pakhtunkhwa Province, Pakistan. The concentrations of the selected metals in soil varied over a wide range, in the following decreasing order: Mn 〉 Zn 〉 Cr 〉 Ni 〉 Cu. The bioaccunmlation of metals in vegetables was within the permissible risk limits, except for Cr which showed higher contamination in all the tested food crops. The trend of metal transfer factors for different vegetables was in the order of Cu 〉 Ni 〉 Cr 〉 Mn 〉 Zn, while the calculated daily intake of metals (DIM) in adults and children through consumption of food crops was in the decreasing order of Mn 〉 Zn 〉 Ni 〉 Cr 〉 Cu. The health risk index (HRI) values for the heavy metals for both adults and children were less than 1. Therefore, no significant health risk is anticipated for the local consumers through ingestion of these food crops.展开更多
This study demonstrated an unconventional way to cure peripheral nerve injury(PNI) with liquid metal gallium employed as the reconnection agent. In vivo experiments were performed, in which transected sciatic nerve of...This study demonstrated an unconventional way to cure peripheral nerve injury(PNI) with liquid metal gallium employed as the reconnection agent. In vivo experiments were performed, in which transected sciatic nerve of mouse was reconnected by liquid metal gallium.The nerve signals detected was found to be almost the same as those from the complete nerve, where the negative bursting firing caused by PNI was absent on the neural discharge curve after nerve-reconnection surgery. Meanwhile the atrophy tendency of gastrocnemius muscle was distinctly procrastinated according to the results of pathological examinations, which showed fibrillation potentials emerged immediately for mice with PNI but did not emerge until the third month for those received nerve-reconnection surgery. Furthermore, physical properties of gallium were studied, showing that its impedance was slightly influenced by the frequency of transmitted signal and the temperature, which confirmed the stability of gallium in future clinical usage. This technology is expected to perform well in clinical surgery for PNI and even central nervous system injury in the coming time.展开更多
China has developed an airborne gravimetry system based on SINS/DGPS named SGA-WZ, the first system in which a strap- down inertial navigation system (SINS) has been used for airborne gravimetry in China. This gravi...China has developed an airborne gravimetry system based on SINS/DGPS named SGA-WZ, the first system in which a strap- down inertial navigation system (SINS) has been used for airborne gravimetry in China. This gravity measurement system consists of a strap-down inertial navigation system and a differential global positioning system (DGPS). In April 2010, a flight test was carried out in Shandong Province of China to test the accuracy of this system. The test was designed to assess the re- peatability and accuracy of the system. Two repeated flights and six grid flights were made. The flying altitude was about 400 m. The average flying speed was about 60 m/s, which corresponds to a spatial resolution of 4.8 km when using 160-s cutoff low-pass filter. This paper describes the data processing of the system. The evaluation of the internal precision is based on repeated flights and differences in crossover points. Gravity results in this test from the repeated flight lines show that the re- peatability of the repeat lines is 1.6 mGal with a spatial resolution of 4.8 kin, and the internal precision of grid flight data is 3.2 mGal with a spatial resolution of 4.8 km. There are some systematic errors in the gravity results, which can be modeled using trigonometric function. After the systematic errors are compensated, the precision of grid flight data can be better than 1 mGal.展开更多
基金supported by the Public Science and Technology Research Funds Projects of Ocean (Nos. 201305043 and 201405010)
文摘In this study, the entire mitochondrial DNA(mtDNA) control region(CR) of Pholis fangi was amplified via polymerase chain reaction followed by direct sequencing. The length of the mtDNA CR consensus sequence of P. fangi was 853 bp in length. In accordance with the recognition sites as were previously reported in fish species, the mtDNA CR sequence of P. fangi can be divided into 3 domains, i.e., the extended terminal associated sequence(ETAS), the central conserved sequence block(CSB), and the CSB domain. In addition, the following structures were identified in the mtDNA CR sequence of P. fangi: 2 ETASs in the ETAS domain(TAS and cTAS), 6 CSBs in the central CSB domain(CSB-F to CSB-A), and 3 CSBs in the CSB domain(CSB-1 to CSB-3). These demonstrated that the structure of the mtDNA CR of P. fangi was substantially different from those of most other fish species. The mtDNA CR sequence of P. fangi contained one conserved region from 656 bp to 815 bp. Similar to most other fish species, P. fangi has no tandem repeat sequences in its mtDNA CR sequence. Phylogenetic analysis based on the complete mtDNA CR sequences showed that there were no genetic differences within P. fangi populations of the same geographical origin and between P. fangi populations of different geographical origins.
文摘Now environment is an important topic in academic field.Many researches focus on the negative outcomes of nature which are being continually created by human and much attention has been paid to how the environment is protected through integrated research,movement and policy.But few studies are concentrated on population and environment and are to find out the interconnectivity and underlying mechanism that have an effect on people's preferring additional children and perception to environment.Many researchers claim that population growth is a great problem for environment but they do not provide the indepth integrated knowledge and mechanism that influence fertility trend and environmental problems.It is very crucial to develop practical and concrete initiatives to confirm a transition to reduce population growth and redirect the perception on population and environment.
基金Supported by the National High Technology Research and Development Programme of China(No.2008AA01A204)the National Natural Science Foundation of China(No.61003047,61173020)International Science & Technology Cooperation Project(No.2010DFA14400)
文摘An optimal maintenance policy tor deteriorating components based on quasi renew-process model is presented. In this policy, the first N - 1 failures of a component are maintained by repairs and the N'h failure is maintained by replacement. The policy takes replacement actions at component lev- el by considering the fact that more and more components are designed to be field replaceable and maintenance activities are setting free from system halt. Concerning system structure impact, impor- tance measure is employed in the optimization procedure which aims at maximizing the long-rnn prof- it per unit time. Two example series parallel systems are taken to illustrate the policy and it is proved to work well. According to importance analysis, components are classified into important ones and unimportant ones based on the system behavior under their failures. Simulation results show that the presented policy makes a clear distinction between them and takes effective mainte- nance actions to compensate the deteriorating of components.
文摘为了解决海量数据分析中的非凸状等复杂聚类问题,同时兼顾聚类算法运算速度,提出了一种新的基于竞争思想的快速分级聚类算法.首先,根据给定邻域半径对数据进行第1级分类;然后,在第1级聚类的基础上,基于数据竞争的思想,以簇间数据密度为依据,设立第1级聚类生成的小簇之间小簇联系性权重的增加准则;最后,依据该准则计算有联系的小簇之间联系权重,对达到权重阈值的小簇进行合并,从而解决非凸状等复杂聚类问题.仿真实验表明,算法的聚类精度和抗噪声能力均优于传统的K-means算法和基于密度的DBSCAN(densitybased spatial clustering of applications with noise)算法.由于算法复杂度较低,算法对于大数据的聚类分析将会具有更好的适用性.
基金supported by the Directorate of Science and Technology, Khyber Pakhtunkhwa, Pakistanthe Higher Education Commission, Islamabad, Pakistansupported by the NIEHS Superfund Research Program (No. ES04940)
文摘Contamination of the food chain with heavy metals is considered as one of the major environmental pathways of human exposure to metals leading to potential health risks. This study aimed to investigate the concentrations of heavy metals such as copper (Cu), zinc (Zn), chromium (Cr), nickel (Ni), and manganese (Mn) in agricultural soils and food crops (fruit, leaf, and root vegetables), and their associated health risks to the local population in selected southern districts of Khyber Pakhtunkhwa Province, Pakistan. The concentrations of the selected metals in soil varied over a wide range, in the following decreasing order: Mn 〉 Zn 〉 Cr 〉 Ni 〉 Cu. The bioaccunmlation of metals in vegetables was within the permissible risk limits, except for Cr which showed higher contamination in all the tested food crops. The trend of metal transfer factors for different vegetables was in the order of Cu 〉 Ni 〉 Cr 〉 Mn 〉 Zn, while the calculated daily intake of metals (DIM) in adults and children through consumption of food crops was in the decreasing order of Mn 〉 Zn 〉 Ni 〉 Cr 〉 Cu. The health risk index (HRI) values for the heavy metals for both adults and children were less than 1. Therefore, no significant health risk is anticipated for the local consumers through ingestion of these food crops.
基金supported by the National Natural Science Foundation of China (51376102)the China Postdoctoral Science Foundation
文摘This study demonstrated an unconventional way to cure peripheral nerve injury(PNI) with liquid metal gallium employed as the reconnection agent. In vivo experiments were performed, in which transected sciatic nerve of mouse was reconnected by liquid metal gallium.The nerve signals detected was found to be almost the same as those from the complete nerve, where the negative bursting firing caused by PNI was absent on the neural discharge curve after nerve-reconnection surgery. Meanwhile the atrophy tendency of gastrocnemius muscle was distinctly procrastinated according to the results of pathological examinations, which showed fibrillation potentials emerged immediately for mice with PNI but did not emerge until the third month for those received nerve-reconnection surgery. Furthermore, physical properties of gallium were studied, showing that its impedance was slightly influenced by the frequency of transmitted signal and the temperature, which confirmed the stability of gallium in future clinical usage. This technology is expected to perform well in clinical surgery for PNI and even central nervous system injury in the coming time.
基金supported by the National High-Tech Research&Development Program of China(Grant No.2006AA06A202)the Youth Innovation Foundation of China Aero Geophysical Survey&Remote Sensing Center for Land and Resources(Grant No.2010YFL05)
文摘China has developed an airborne gravimetry system based on SINS/DGPS named SGA-WZ, the first system in which a strap- down inertial navigation system (SINS) has been used for airborne gravimetry in China. This gravity measurement system consists of a strap-down inertial navigation system and a differential global positioning system (DGPS). In April 2010, a flight test was carried out in Shandong Province of China to test the accuracy of this system. The test was designed to assess the re- peatability and accuracy of the system. Two repeated flights and six grid flights were made. The flying altitude was about 400 m. The average flying speed was about 60 m/s, which corresponds to a spatial resolution of 4.8 km when using 160-s cutoff low-pass filter. This paper describes the data processing of the system. The evaluation of the internal precision is based on repeated flights and differences in crossover points. Gravity results in this test from the repeated flight lines show that the re- peatability of the repeat lines is 1.6 mGal with a spatial resolution of 4.8 kin, and the internal precision of grid flight data is 3.2 mGal with a spatial resolution of 4.8 km. There are some systematic errors in the gravity results, which can be modeled using trigonometric function. After the systematic errors are compensated, the precision of grid flight data can be better than 1 mGal.