This study is based on the Tong sheep obtained by the random sampling method of typical colonies in the central area of Baishui County in Shaanxi Province, China. An investigation was undertaken to clarify the gene co...This study is based on the Tong sheep obtained by the random sampling method of typical colonies in the central area of Baishui County in Shaanxi Province, China. An investigation was undertaken to clarify the gene constitution of blood protein and nonprotein types of Tong sheep. Twelve genetic markers were examined by starch-gel electrophoresis and cellulose acetate electrophoresis. Polymorphism in Tong sheep was found at the following 10 loci, transferrin (Tf), alkaline phosphatase (Alp), leucine aminopeptidase (Lap), arylesterase (Ary-Es), hemoglobin-β (Hb-β), X-protein (X-p), carbonic anhydrase (CA), catalase (Cat), malate dehydrogenase (MDH), and lysine (Ly), whereas, albumin (A1) and postalbumin (Po) loci were monomorphic. Genetic approach degree method and phylogenetic relationship clustering method were used to judge the origin and phylogenetic status of Tong sheep. Results from both methods maintained that Tong sheep belonged to the "Mongolia group", and Mongolia sheep was the origin of Tong sheep. This was also supported by the history of Tong sheep breeding. Compared to the phylogenetic relationship clustering method, the genetic approach degree method was more reliable for the extraction from East and South of Central Asia, and was more effective in reflecting the breeding course of Tong sheep.展开更多
Objective To evaluate left univentricular (LUV) pacing for cardiac resynchronization therapy (CRT) using a rate-adaptive atrioven- tricular delay (RAAVD) algorithm to track physiological atrioventricular delay ...Objective To evaluate left univentricular (LUV) pacing for cardiac resynchronization therapy (CRT) using a rate-adaptive atrioven- tricular delay (RAAVD) algorithm to track physiological atrioventricular delay (AVD). Methods A total of 72 patients with congestive heart failure (CHF) were randomized to RAAVD LUV pacing versus standard biventricular (BiV) pacing in a 1 : 1 ratio. Echocardiography was used to optimize AVD for both groups. The effects of sequential BiV pacing and LUV pacing with optimized A-V (right atrio-LV) delay using an RAAVD algorithm were compared. The standard deviation (SD) of the S/R ratio in lead VI at five heart rate (HR) segments (Rs/R-SD5), defined as the "tracking index," was used to evaluate the accuracy of the RAAVD algorithm for tracking physiological AVD. Results TheQRS complex duration (132 ± 9.8 vs. 138± 10ms, P 〈 0.05), the time required for optimization (21 ±5 vs. 50±8min, P〈 0.001), the mitral regurgitant area (1.9 ± 1.1 vs. 2.5 ± 1.3 em2, P 〈 0.05), the interventricular mechanical delay time (60.7 ± 13.3 ms vs. 68.3 ± 14.2 ms, P 〈 0.05), and the average annual cost (13,200 ± 1000 vs. 21,600 ± 2000 RMB, P 〈 0.001) in the RAAVD LUV pacing group were significantly less than those in the standard BiV pacing group. The aortic valve velocity-time integral in the RAAVD LUV pacing group was greater than that in the standard BiV pacing group (22.7 ± 2.2 vs. 21.4 ± 2.1 cm, P 〈 0.05). The Rs/R-SD5 was 4.08 ± 1.91 in the RAAVD LUV pacing group, and was significantly negatively correlated with improved left ventricular ejection fraction (LVEF) (ALVEF, Pearson's r = -0.427, P = 0.009), and positively correlated with New York Heart Association class (Spearman's r - 0.348, P 0.037). Conclusions RAAVD LUV pacing is as effective as standard BiV pacing, can be more physiological than standard BiV pacing, and can de- crease the average annual cost of CRT.展开更多
The authors have proposed a new of magnetic isotope theory of life on Earth. According to this theory the initial impetus for the beginning of the synthesis of organic compounds is the impact of electromagnetic radiat...The authors have proposed a new of magnetic isotope theory of life on Earth. According to this theory the initial impetus for the beginning of the synthesis of organic compounds is the impact of electromagnetic radiation from the sun and energy radioactive isotopes.展开更多
Based on the large-scale model tests, a simplified dam breach model for homogeneous cohesive dam due to overtopping failure is put forward. The model considers headcut erosion as one of the key homogeneous cohesive da...Based on the large-scale model tests, a simplified dam breach model for homogeneous cohesive dam due to overtopping failure is put forward. The model considers headcut erosion as one of the key homogeneous cohesive dam breaching mechanisms and we calculate the time-averaged headcut migration rate using an energy-based empirical formula. A numerical method is adopted to determine the initial scour position at the downstream slope in terms of the water head and dam height, and the broad-crested weir equation is utilized to simulate the breach flow. The limit equilibrium method is used to analyze the stability of breach slope during the breach process. An iterative method is developed to simulate the coupling process of soil and water at each time step. The calculated results of three dam breach cases testify the reasonability of the model, and the sensitivity studies of soil erodibility show that sensitivity is dependent on each test case's soil conditions. In addition, three typical dam breach models, NWS BREACH, WinDAM B, and HR BREACH, are also chosen to compare with the proposed model. It is found that NWS BREACH may have large errors for cohesive dams, since it uses a noncohesive sediment transport model and does notconsider headcut erosion, WinDAM B and HR BREACH consider headcut erosion as the breaching mechanism and handle well homogeneous cohesive dam overtopping failure, but overall, the proposed model has the best performance.展开更多
The fishery quota management system is an output control fishery management mode based on ecological characteristics of the ifshery resource under the historical context of overifshing-caused ifshery crises and the fa...The fishery quota management system is an output control fishery management mode based on ecological characteristics of the ifshery resource under the historical context of overifshing-caused ifshery crises and the failure of traditional input control management. This system depends on total al owable catch and has been successful y implemented in Iceland, New Zealand and other countries. Chinese researchers hold different views on the legal characteristics of the quota system, but the majority identify the characteristics as quasi-property. Based on the biological nature of the resources and substance of the system, international and domestic quota systems can achieve substantial results only when they strictly follow the joint obligation of remaining below the total al owable catch and the obligation shal be performed by limited access, strengthening supervision and other means to realize sustainable use.展开更多
Synchronization is considered to be a crucial mechanism that maintains respiratory rhythm.For understanding the effect of electrical coupling on the transition of the firing patterns and synchronization,we coupled two...Synchronization is considered to be a crucial mechanism that maintains respiratory rhythm.For understanding the effect of electrical coupling on the transition of the firing patterns and synchronization,we coupled two inspiratory pacemaker neurons together,and studied various synchronous behaviors between them.We firstly compared the bifurcation diagrams between the coupled neurons and single neuron,and found that the coupled neurons had a more complicated bifurcation mode.By increasing the coupling strength,the regular variation of phase differences was illustrated so that asynchronous and some synchronous states could be observed.These synchronous states were also shown in detail by phase portraits and firing series.In addition,we explored the ranges of different synchronous states,which attributed to different ranges of membrane capacitance and coupling strength.展开更多
The term "extreme environments" describes the conditions that deviate from what mesophilic cells can tolerate. These condi- tions are "extreme" in the eye of mankind, but they may be suitable or even essential liv...The term "extreme environments" describes the conditions that deviate from what mesophilic cells can tolerate. These condi- tions are "extreme" in the eye of mankind, but they may be suitable or even essential living conditions for most microorgan- isms. Hypertherrnophilic microorganisms form a branch at the root of the phylogenetic tree, indicating that early life originated from extreme environments similar to that of modern deep-sea hydrothermal vents, which are characterized by high-tempera- ture and oxygen-limiting conditions. During the inevitable cooling and gradual oxidation process on Earth, microorganisms developed similar mechanisms of adaptation. By studying modem extremophiles, we may be able to decode the mysterious history of their genomic evolution and to reconstruct e~,rly life. Because life itself is a process of energy uptake to maintain a dissipative structure that is not in thermodynamic equilibrium, the energy metabolism of microorganisms determines the path- way of evolution, the structure of an ecosystem, and the physiology of cells. "Following energy" is an essential approach to understand the boundaries of life and to search for life beyond Earth.展开更多
Boron concentrations and isotope compositions have been measured for 93 water samples from the hot springs and drill-holes in the geothermal system in the Yunnan-Tibet Geothermal Belt(YTGB),China.Boron concentrations ...Boron concentrations and isotope compositions have been measured for 93 water samples from the hot springs and drill-holes in the geothermal system in the Yunnan-Tibet Geothermal Belt(YTGB),China.Boron concentrations range from 0.036–472.4ppm,and theδ11B values range from -16.0‰to 13.1‰,indicating the non-marine origin for each geothermal system.We observed a clear binary mixing relationship between the B concentrations and B isotope compositions in Tibet geothermal area.This relationship can be well explained by two sources,i.e.,marine carbonate rocks and magmatic rocks,for the Tibet geothermal water.No evidence supports a mantle contribution to B.In addition,we found that the precipitation only plays a dilution role for B of geothermal waters.δ11B values for the precipitation across the southern Tibetan Plateau area range from -6.0‰ to -6.8‰at least.Due to data scarcity in Yunnan geothermal area,we observed possible different boron sources from the Tibet geothermal system.Comparing it with other geothermal systems in the world,we found that the samples from YTGB have the lowestδ11B values and the largest range of B concentration,which might be related to their special geological background.On the whole,the world geothermalδ11B-Cl/B relation suggests a mixing process between marine and non-marine sources.Additionally,we suggest that B source of B-enriched geothermal waters is mainly from B-enriched crustal country-rocks,instead of mantle.展开更多
In the Dongting water system, the Carassius auratus(Crucian carp) complex is characterized by the coexistence of diploid forms(2n=100, 2n CC) and polyploid forms. Chromosomal and karyotypic analyses have suggested tha...In the Dongting water system, the Carassius auratus(Crucian carp) complex is characterized by the coexistence of diploid forms(2n=100, 2n CC) and polyploid forms. Chromosomal and karyotypic analyses have suggested that the polyploid C. auratus has a triploid(3n=150, 3n CC) and a tetraploid origin(4n=200), respectively. However, there is a lack of direct genetic evidence to support this conclusion. In this paper, analysis of the 5S r DNA chromosomal locus revealed that the 3n CC is of triploid origin. Analysis of the species-specific chromosomal centromere locus revealed that 3n CC individuals possess three sets of C. auratus-derived chromosomes. Our results provide direct cytogenetic evidence suggesting that individuals with 150 chromosomes are of autotriploid origin within the C. auratus complex. It marks an important contribution to the study of polyploidization and the evolution of vertebrates.展开更多
基金the International Cooperation Item of the National Natural Science Foundation of China (No. 30213009, 30310103007, 30410103150)Natural Science Foundation of Jiangsu Province of China (No. BK2007556)+1 种基金Basic Natura Science Foundation for Colleges and Universities Jiangsu Province (No. NK051039) the New Century Talent Project of Yangzhou University in China.
文摘This study is based on the Tong sheep obtained by the random sampling method of typical colonies in the central area of Baishui County in Shaanxi Province, China. An investigation was undertaken to clarify the gene constitution of blood protein and nonprotein types of Tong sheep. Twelve genetic markers were examined by starch-gel electrophoresis and cellulose acetate electrophoresis. Polymorphism in Tong sheep was found at the following 10 loci, transferrin (Tf), alkaline phosphatase (Alp), leucine aminopeptidase (Lap), arylesterase (Ary-Es), hemoglobin-β (Hb-β), X-protein (X-p), carbonic anhydrase (CA), catalase (Cat), malate dehydrogenase (MDH), and lysine (Ly), whereas, albumin (A1) and postalbumin (Po) loci were monomorphic. Genetic approach degree method and phylogenetic relationship clustering method were used to judge the origin and phylogenetic status of Tong sheep. Results from both methods maintained that Tong sheep belonged to the "Mongolia group", and Mongolia sheep was the origin of Tong sheep. This was also supported by the history of Tong sheep breeding. Compared to the phylogenetic relationship clustering method, the genetic approach degree method was more reliable for the extraction from East and South of Central Asia, and was more effective in reflecting the breeding course of Tong sheep.
文摘Objective To evaluate left univentricular (LUV) pacing for cardiac resynchronization therapy (CRT) using a rate-adaptive atrioven- tricular delay (RAAVD) algorithm to track physiological atrioventricular delay (AVD). Methods A total of 72 patients with congestive heart failure (CHF) were randomized to RAAVD LUV pacing versus standard biventricular (BiV) pacing in a 1 : 1 ratio. Echocardiography was used to optimize AVD for both groups. The effects of sequential BiV pacing and LUV pacing with optimized A-V (right atrio-LV) delay using an RAAVD algorithm were compared. The standard deviation (SD) of the S/R ratio in lead VI at five heart rate (HR) segments (Rs/R-SD5), defined as the "tracking index," was used to evaluate the accuracy of the RAAVD algorithm for tracking physiological AVD. Results TheQRS complex duration (132 ± 9.8 vs. 138± 10ms, P 〈 0.05), the time required for optimization (21 ±5 vs. 50±8min, P〈 0.001), the mitral regurgitant area (1.9 ± 1.1 vs. 2.5 ± 1.3 em2, P 〈 0.05), the interventricular mechanical delay time (60.7 ± 13.3 ms vs. 68.3 ± 14.2 ms, P 〈 0.05), and the average annual cost (13,200 ± 1000 vs. 21,600 ± 2000 RMB, P 〈 0.001) in the RAAVD LUV pacing group were significantly less than those in the standard BiV pacing group. The aortic valve velocity-time integral in the RAAVD LUV pacing group was greater than that in the standard BiV pacing group (22.7 ± 2.2 vs. 21.4 ± 2.1 cm, P 〈 0.05). The Rs/R-SD5 was 4.08 ± 1.91 in the RAAVD LUV pacing group, and was significantly negatively correlated with improved left ventricular ejection fraction (LVEF) (ALVEF, Pearson's r = -0.427, P = 0.009), and positively correlated with New York Heart Association class (Spearman's r - 0.348, P 0.037). Conclusions RAAVD LUV pacing is as effective as standard BiV pacing, can be more physiological than standard BiV pacing, and can de- crease the average annual cost of CRT.
文摘The authors have proposed a new of magnetic isotope theory of life on Earth. According to this theory the initial impetus for the beginning of the synthesis of organic compounds is the impact of electromagnetic radiation from the sun and energy radioactive isotopes.
基金Natural Science Foundation of China(Grant No.51379129,51539006,51509164)
文摘Based on the large-scale model tests, a simplified dam breach model for homogeneous cohesive dam due to overtopping failure is put forward. The model considers headcut erosion as one of the key homogeneous cohesive dam breaching mechanisms and we calculate the time-averaged headcut migration rate using an energy-based empirical formula. A numerical method is adopted to determine the initial scour position at the downstream slope in terms of the water head and dam height, and the broad-crested weir equation is utilized to simulate the breach flow. The limit equilibrium method is used to analyze the stability of breach slope during the breach process. An iterative method is developed to simulate the coupling process of soil and water at each time step. The calculated results of three dam breach cases testify the reasonability of the model, and the sensitivity studies of soil erodibility show that sensitivity is dependent on each test case's soil conditions. In addition, three typical dam breach models, NWS BREACH, WinDAM B, and HR BREACH, are also chosen to compare with the proposed model. It is found that NWS BREACH may have large errors for cohesive dams, since it uses a noncohesive sediment transport model and does notconsider headcut erosion, WinDAM B and HR BREACH consider headcut erosion as the breaching mechanism and handle well homogeneous cohesive dam overtopping failure, but overall, the proposed model has the best performance.
基金National Social Science Fund Youth Support Project(12CFX091)Shandong University Humanities and Social Science Research Project(J12WB11)+1 种基金Shandong University of Technology Humanities and Social Development Plan(4083/112007)Shandong University of Technology Young Teacher Development Support Program(4072/112030)
文摘The fishery quota management system is an output control fishery management mode based on ecological characteristics of the ifshery resource under the historical context of overifshing-caused ifshery crises and the failure of traditional input control management. This system depends on total al owable catch and has been successful y implemented in Iceland, New Zealand and other countries. Chinese researchers hold different views on the legal characteristics of the quota system, but the majority identify the characteristics as quasi-property. Based on the biological nature of the resources and substance of the system, international and domestic quota systems can achieve substantial results only when they strictly follow the joint obligation of remaining below the total al owable catch and the obligation shal be performed by limited access, strengthening supervision and other means to realize sustainable use.
基金supported by the National Natural Science Foundation of China(Grant No.11172103)
文摘Synchronization is considered to be a crucial mechanism that maintains respiratory rhythm.For understanding the effect of electrical coupling on the transition of the firing patterns and synchronization,we coupled two inspiratory pacemaker neurons together,and studied various synchronous behaviors between them.We firstly compared the bifurcation diagrams between the coupled neurons and single neuron,and found that the coupled neurons had a more complicated bifurcation mode.By increasing the coupling strength,the regular variation of phase differences was illustrated so that asynchronous and some synchronous states could be observed.These synchronous states were also shown in detail by phase portraits and firing series.In addition,we explored the ranges of different synchronous states,which attributed to different ranges of membrane capacitance and coupling strength.
基金supported by National Natural Science Foundation of China (Grant No. 31290232)National High-Tech Program (Grant No. 2012AA092103-2)National Basic Research Program of China (Grant No. 2011CB808800)
文摘The term "extreme environments" describes the conditions that deviate from what mesophilic cells can tolerate. These condi- tions are "extreme" in the eye of mankind, but they may be suitable or even essential living conditions for most microorgan- isms. Hypertherrnophilic microorganisms form a branch at the root of the phylogenetic tree, indicating that early life originated from extreme environments similar to that of modern deep-sea hydrothermal vents, which are characterized by high-tempera- ture and oxygen-limiting conditions. During the inevitable cooling and gradual oxidation process on Earth, microorganisms developed similar mechanisms of adaptation. By studying modem extremophiles, we may be able to decode the mysterious history of their genomic evolution and to reconstruct e~,rly life. Because life itself is a process of energy uptake to maintain a dissipative structure that is not in thermodynamic equilibrium, the energy metabolism of microorganisms determines the path- way of evolution, the structure of an ecosystem, and the physiology of cells. "Following energy" is an essential approach to understand the boundaries of life and to search for life beyond Earth.
基金supported by National Natural Science Foundation of China(Grant Nos.41203012,41030317)China Geological Survey(Grant No.1212011085524)
文摘Boron concentrations and isotope compositions have been measured for 93 water samples from the hot springs and drill-holes in the geothermal system in the Yunnan-Tibet Geothermal Belt(YTGB),China.Boron concentrations range from 0.036–472.4ppm,and theδ11B values range from -16.0‰to 13.1‰,indicating the non-marine origin for each geothermal system.We observed a clear binary mixing relationship between the B concentrations and B isotope compositions in Tibet geothermal area.This relationship can be well explained by two sources,i.e.,marine carbonate rocks and magmatic rocks,for the Tibet geothermal water.No evidence supports a mantle contribution to B.In addition,we found that the precipitation only plays a dilution role for B of geothermal waters.δ11B values for the precipitation across the southern Tibetan Plateau area range from -6.0‰ to -6.8‰at least.Due to data scarcity in Yunnan geothermal area,we observed possible different boron sources from the Tibet geothermal system.Comparing it with other geothermal systems in the world,we found that the samples from YTGB have the lowestδ11B values and the largest range of B concentration,which might be related to their special geological background.On the whole,the world geothermalδ11B-Cl/B relation suggests a mixing process between marine and non-marine sources.Additionally,we suggest that B source of B-enriched geothermal waters is mainly from B-enriched crustal country-rocks,instead of mantle.
基金supported by the National Natural Science Foundation of China (31201987, 31430088, 31210103918)the Doctoral Fund of Ministry of Education of China (20124306120006)+4 种基金the Natural Science Foundation of Hunan Province (14JJ6008)Training Program of the Major Research Plan of the National Natural Science Foundation of China (91331105)the National Key Basic Research Program of China (2012CB722305)the Cooperative Innovation Center of Engineering and New Products for Developmental Biology (20134486)the Construct Program of the Key Discipline in Hunan Province, China
文摘In the Dongting water system, the Carassius auratus(Crucian carp) complex is characterized by the coexistence of diploid forms(2n=100, 2n CC) and polyploid forms. Chromosomal and karyotypic analyses have suggested that the polyploid C. auratus has a triploid(3n=150, 3n CC) and a tetraploid origin(4n=200), respectively. However, there is a lack of direct genetic evidence to support this conclusion. In this paper, analysis of the 5S r DNA chromosomal locus revealed that the 3n CC is of triploid origin. Analysis of the species-specific chromosomal centromere locus revealed that 3n CC individuals possess three sets of C. auratus-derived chromosomes. Our results provide direct cytogenetic evidence suggesting that individuals with 150 chromosomes are of autotriploid origin within the C. auratus complex. It marks an important contribution to the study of polyploidization and the evolution of vertebrates.