In the traditional unscented Kalman filter(UKF),accuracy and robustness decline when uncertain disturbances exist in the practical system.To deal with the problem,a robust UKF algorithm based on an H-infinity norm i...In the traditional unscented Kalman filter(UKF),accuracy and robustness decline when uncertain disturbances exist in the practical system.To deal with the problem,a robust UKF algorithm based on an H-infinity norm is proposed.In Krein space,a robust element is added in the simplified UKF so as to improve the algorithm.The filtering gain is adjusted by the robust element and in this way the performance of the robustness of the filtering algorithm is promoted.In the initial alignment process of the large heading misalignment angle of the strapdown inertial navigation system(SINS),comparative studies are conducted on the robust UKF and the simplified UKF.The simulation results illustrate that compared with the simplified UKF,the robust UKF is more accurate,and the estimation error of heading misalignment decreases from 16.9' to 4.3'.In short,the robust UKF can reduce the sensitivity to the system disturbances resulting in better performance.展开更多
Objective: To study the features of microsatellite alterations on chromosome 8 and their asso- ciation with clinicopathological characteristics of hepatocellular carcinoma (HCC). Methods: Ten highly- ...Objective: To study the features of microsatellite alterations on chromosome 8 and their asso- ciation with clinicopathological characteristics of hepatocellular carcinoma (HCC). Methods: Ten highly- polymorphic microsatellite markers on chromosome 8 were selected to be detected for loss of heterozygosity (LOH), microsatellite instability (MSI) and allelic imbalance (AI) in 56 HCC using MegaBACE 500 auto- matic DNA analysis system. Results: LOH was found in 37 of 56 HCC (66.1%) on at least 1 locus, and the top three loci were D8S261(53.5%), D8S1721(52.5%) and D8S1771(52.5%). LOH frequency on D8S277 was signi?cantly higher in cases positive for serum HBsAg than in those negative for HBsAg (P <0.01). Similarly, LOH on D8S261, D8S298 and D8S1733 occurred more frequently in patients with negative HB- sAg than those with positive HBsAg (P <0.01). LOH on D8S298 and D8S1771 was more frequent in those tumors larger than 3 cm in size (P <0.05 or P <0.01). LOH frequencies of D8S1721 were signi?cantly higher in the patients with absent or not intact tumor capsule than in those with intact tumor capsule (P <0.05). LOH on D8S298 and D8S1771 was more frequently detected in tumors with intrahepatic metastasis than in those without intrahepatic metastasis (P <0.01). MSI was found in 12.5% (7/56) cases, and AI was found in 19.6% (11/56), no correlation was found between MSI and AI and clinicopathological character- istics of HCC. Conclusion: Frequent microsatellite alterations on chromosome 8 existed in HCC. LOH, which represents tumor suppressor gene pathway, plays a more important role in hepatocarcinogenesis; MSI representing mismatch repair gene pathway ranks next. LOH at a particula locus is associated with the clinicopathological parameters of human HCC.展开更多
Objective To observe therapeutic effects of acupuncture combined with language training on aphasia induced by ischemic apoplexy and investigate the mechanisms. Methods 60 patients were randomly divided into a treatmen...Objective To observe therapeutic effects of acupuncture combined with language training on aphasia induced by ischemic apoplexy and investigate the mechanisms. Methods 60 patients were randomly divided into a treatment group treated by acupuncture associated with language training and a control group treated by simple language training. Tongue-acupuncture was applied as the main therapy, and language training included speech organ training, mouth-shape and voice training, spoken language expression training and practical communication ability training. According to Aphosio Bottery of Chinese (ABC), language ex- amination evaluation was made, and event related potential (P300) was detected before and after treatment. Results The therapeutic effect in the treatment group was significantly better than that in the control group (P〈O. 05), and the scores of ABC items including information content, speech fluency, repetition, vocabula- ry denomination, color naming, response denomination, confirmation or negation, acoustic recognition and carrying out instruction in the treatment group were obviously higher than those in the control group (P〈0.05). After one course of treatment, the latencies of N2 and P3 waves in P300 were significantly short- ened and the amplitude of P3 was significantly elevated in the treatment group, compared with those in the control group (P〈0.05). Conclusion Acupuncture combined with language training provided remarkable therapeutic effects in treating cerebral infarction-induced motor aphasia, and it was better than simple lan- guage training. The results of enhancing of the ABC scores including information content, speech fluency, repetition, vocabulary denomination, color naming, response denomination, confirmation or negation, acous- tic recognition and carrying out instruction, and shortening of the latencies of N2 and P3 waves in P300 and ele- vation of P3 amplitude may be taken as the indices for evaluating and anticipating clinical therapeutic effects of the therapy for treating the disease, which may also be some of the mechanisms.展开更多
Two plastid division genes, NtFtsZ1 and NtFtsZ2 isolated from Nicotiana tabacum L. were fused with gfp and expressed in Escherichia coli . The regular localizations of full length NtFtsZs∶GFP along the fil...Two plastid division genes, NtFtsZ1 and NtFtsZ2 isolated from Nicotiana tabacum L. were fused with gfp and expressed in Escherichia coli . The regular localizations of full length NtFtsZs∶GFP along the filamentous bacteria indicated that the NtFtsZs could recognize the potential division sites in E. coli and be polymerized with heterogeneous FtsZ from bacteria. The overexpression of NtFtsZs ∶ gfp inhibited the division of host strain cells and resulted in the long filamentous bacterial morphology. These results suggested that eukaryotic ftsZs have similar function to their prokaryotic homologs. Meanwhile, the different deletions of motifs of NtFtsZs are also employed to investigate the functions of these proteins in E. coli . The results showed that the C_terminal domains of NtFtsZs were related to the correct localization of NtFtsZs in E. coli and the N_terminal domains of NtFtsZs were responsible for the polymerization of homogeneous and heterogeneous FtsZ proteins. The significance of these results in understanding the functions of NtFtsZs in plastid division were discussed.展开更多
This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantiti...This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantities of this system in equilibrium are obtained.展开更多
Using patch clamp whole cell recording techiques, we examined the effects ofIQ_23, a benzyl-isoquinoline derivative with antiarrhythmic activities, on the action potential (AP) andpotassium currents in single guinea p...Using patch clamp whole cell recording techiques, we examined the effects ofIQ_23, a benzyl-isoquinoline derivative with antiarrhythmic activities, on the action potential (AP) andpotassium currents in single guinea pig ventricular myocytes. The results showed that IQ_23 at 10, 30and 100 μmol ·L_-1 slowed the repolarization in AP dose-dependently. The APD_90 were prolonged by15%, 28% and 31% respectively. This effect did not depend on the extracellular Ca^2+. In voltageclamp mode, IQ_23 effectively blocked both the components of the delayed rectifier potassium current(I_k), i.e., I_ks and I_kr. At concentrations of 30 and 100 μmol· L^-1, IQ_23 suppressed I_ks by 21% and 26%and suppressed I_kr by 67% and 86% respectively. But even at 100 μmol·L^-1, IQ_23 had little effect onthe inward rectifier potassium current (I_k1). It is concluded: 1. IQ_23 can dose-dependently prolongAPD in the ventriculas myocytes of guinea pig, the effect does not depend on the extracellular Ca^2+; 2.IQ_23 blocks both I_ks and Ikr in the ventricular myocytes without obvious specificities between them.展开更多
This work aimed to quantify the physical and mechanical behavior of three-dimensional microstructures in rocks under uniaxial compression.A high-precision in situ XCT(X-ray transmission computed tomography)technology ...This work aimed to quantify the physical and mechanical behavior of three-dimensional microstructures in rocks under uniaxial compression.A high-precision in situ XCT(X-ray transmission computed tomography)technology was applied to investigating the behavior of mineral grains in sandstone:the movement,the rotation deformation,and the principal strains between fault zone and non-fault zone.The results indicate that after unloading,the shear strain of mineral grains is periodic in the radial direction,the strain of mineral grains in the fracture zone is about 30 times of the macro strain of the specimen,which is about 5 times in the non-fracture zone,and the shear strain near the fault zone is larger than the compressive strain,and there is the shear stress concentration feature.展开更多
The corrosion behavior of the Cu-Ti alloys with different Ti contents in 3.5%(mass fraction)NaCl solution was investigated using electrochemical measurements,immersion tests,mass loss measurements and SEM observation....The corrosion behavior of the Cu-Ti alloys with different Ti contents in 3.5%(mass fraction)NaCl solution was investigated using electrochemical measurements,immersion tests,mass loss measurements and SEM observation.The results show that Ti dissolved in the Cu matrix changes the corrosion process of the alloys.Pure Cu sample exhibits a typical active–passive-transpassive corrosion behavior.The anodic polarization current densities of the Cu-Ti alloys steadily increase with increasing applied potential,indicating that active dissolution of copper proceeds due to the potential difference in the galvanic coupling of Cu and Ti.The increase of Ti content decreases the corrosion resistance of the Cu-Ti alloys.展开更多
Using patch clamp whole cell recording techiques, we examined the effects ofIQ<sub>2</sub>3, a benzyl-isoquinoline derivative with antiarrhythmic activities, on the action potential (AP) andpotassium cur...Using patch clamp whole cell recording techiques, we examined the effects ofIQ<sub>2</sub>3, a benzyl-isoquinoline derivative with antiarrhythmic activities, on the action potential (AP) andpotassium currents in single guinea pig ventricular myocytes. The results showed that IQ<sub>2</sub>3 at 10, 30and 100 μmol ·L<sub>-</sub>1 slowed the repolarization in AP dose-dependently. The APD<sub>9</sub>0 were prolonged by15%, 28% and 31% respectively. This effect did not depend on the extracellular Ca<sup>2</sup>+. In voltageclamp mode, IQ<sub>2</sub>3 effectively blocked both the components of the delayed rectifier potassium current(I<sub>k</sub>), i.e., I<sub>k</sub>s and I<sub>k</sub>r. At concentrations of 30 and 100 μmol· L<sup>-</sup>1, IQ<sub>2</sub>3 suppressed I<sub>k</sub>s by 21% and 26%and suppressed I<sub>k</sub>r by 67% and 86% respectively. But even at 100 μmol·L<sup>-</sup>1, IQ<sub>2</sub>3 had little effect onthe inward rectifier potassium current (I<sub>k</sub>1). It is concluded: 1. IQ<sub>2</sub>3 can dose-dependently prolongAPD in the ventriculas myocytes of guinea pig, the effect does not depend on the extracellular Ca<sup>2</sup>+; 2.IQ<sub>2</sub>3 blocks both I<sub>k</sub>s and Ikr in the ventricular myocytes without obvious specificities between them.展开更多
Cystic dystrophy of the duodenal wall is a rare condition characterized by the development of cysts in heterotopic pancreatic tissue localized in the duodenal wall.A 38-year- old man was admitted to the hospital for a...Cystic dystrophy of the duodenal wall is a rare condition characterized by the development of cysts in heterotopic pancreatic tissue localized in the duodenal wall.A 38-year- old man was admitted to the hospital for abdominal pain and vomiting after food intake.The diagnosis of acute pancreatitis was initially suspected.Abdominal ultrasound examination revealed thickening of the second portion of duodenal wall within which,small cysts(diameter,less than 1 cm)were present in the vicinity of pancreatic head. The head of pancreas appeared enlarged(63 mm×42 mm) and hypoechoic.Upper endoscopy and barium X-ray series were performed revealing a severe circumferential deformation,as well as 4 cm long stenosis of the second portion of the duodenum.CT examination revealed multiple cysts located in an enlarged,thickened duodenal wall with moderate to strong post-contrast enhancement.We suspected that patient had cystic dystrophy of duodenal wall developed in the heterotopic pancreas and diagnosis was confirmed by endoscopic ultrasound(EUS).Endoscopic ultrasound(EUS)revealed circular stenosis from the duodenal bulb onwards.A twenty megahertz mini-prope examination further showed diffuse(intramural)infiltration of duodenal wall limited to the submucosa and muscularis propria of the second portion of duodenum with multiple microcysts within the thickened mucosa and submucosa.Patient was successfully surgically treated and pancreatoduodenectomy was performed.The pathological examination confirmed a diagnosis of cystic dystrophy of a heterotopic pancreas. Endoscopic ultrasonography features allow preoperative diagnosis of cystic dystrophy of a heterotopic pancreas in duodenal wall,with intralumina120 MHz mini probe sonography being more efficient in cases of luminal stenosis.展开更多
This paper presents a powerful approach to find the optimal size and location of distributed generation units in a distribution system using GA (Genetic Optimization algorithm). It is proved that GA method is fast a...This paper presents a powerful approach to find the optimal size and location of distributed generation units in a distribution system using GA (Genetic Optimization algorithm). It is proved that GA method is fast and easy tool to enable the planners to select accurate and the optimum size of generators to improve the system voltage profile in addition to reduce the active and reactive power loss. GA fitness function is introduced including the active power losses, reactive power losses and the cumulative voltage deviation variables with selecting weight of each variable. GA fitness function is subjected to voltage constraints, active and reactive power losses constraints and DG size constraint.展开更多
Generalist mammalian predators hunt for prey in different ways than raptors,often relying on ambush attack.Such differences in predator behavior can have profound effects on susceptibility of different species of prey...Generalist mammalian predators hunt for prey in different ways than raptors,often relying on ambush attack.Such differences in predator behavior can have profound effects on susceptibility of different species of prey to predation,but can also modify the behavior of prey.We investigated susceptibility of common birds to predation by domestic cats Felis catus,relying on an extensive data set on prey abundance and prey availability as determined by standardized bird counts.Susceptibility to cat predation for different species of birds was not significantly correlated with susceptibility to predation by sparrowhawk Accipiter nisus,but with susceptibility to goshawk Accipiter gentilis predation. Susceptibility to goshawk predation was independently predicted by susceptibility to cat and sparrowhawk predation.We cross-validated our estimate of susceptibilityto cat predation by showing that the frequency of birds with tail loss increased strongly with sus-ceptibility to cat predation.Male birds were disproportionately preyed upon,especially if havingsong posts low in the vegetation,and if having short flight distances when singing.Colonially breeding species were less susceptible to predation than solitary species.Bird species with high levels of innate immune defense against bacterial infections had high susceptibility to cat predation.These findings suggest that predation by cats has been an important selection pressure affecting anti-predation behavior,sexual display and immune function in common birds.展开更多
Glaciers in the Tomor region of Tianshan Mountains preserve vital water resources. However, these glaciers suffer from strong mass losses in the recent years because of global warming. From 2008 to 2009, a large-scale...Glaciers in the Tomor region of Tianshan Mountains preserve vital water resources. However, these glaciers suffer from strong mass losses in the recent years because of global warming. From 2008 to 2009, a large-scale scientific expedition has been carried out in this region. As an individual reference glacier, the tongue area of Qingbingtan glacier No. 72 was measured by the high precise Real Time Kinematic-Global Position System (RTK-GPS). In this paper, changes of the tongue area of Qingbingtan glacier No.72 has been studied based on topographic map, remote sensing image and the survey during 2008-2009 field campaign. Results indicated that the ice surface-elevation of the tongue area changed - 0.22~0.14 m a-1 from 1964 to 2008. The estimated loss in ice volume was 0.0144-0.009 km3, which represented a ~20 % decrease from the 1964 volume and was equivalent to average annual mass balance of -0.204-0.12 m water equivalent for the tongue area during 1964-2oo8. Terminus retreated by 1852 m, approximately 41 m a-1, with the area reduction of 1.533 km2 (0.034 km2 a-0 from 1964 to 2009. Furthermore, the annual velocity reached to -70 m a-1. Comparing with the other monitored glaciers in the eastern Tianshan Mountains, Qingbingtan glacier No.72 experienced more intensive in shrinkage, which resulted from the combined effects of climate change and glacier dynamic, providing evidence of the response to climatic warming.展开更多
Liczberski-Starkov firstfound a lower bound for ||D(f)|| near the origin, where f(z)=(F(z1),√F1(z1)z2,…,√F'(z1)zn)'is the Roper-Suffridge operator on the unit ball Bn in Cn and F is a normalized c...Liczberski-Starkov firstfound a lower bound for ||D(f)|| near the origin, where f(z)=(F(z1),√F1(z1)z2,…,√F'(z1)zn)'is the Roper-Suffridge operator on the unit ball Bn in Cn and F is a normalized convex function on the unit disk. Later, Liczberski-Starkov and Hamada-Kohr proved the lower bound holds on the whole unit ball using a complex computation. Here we provide a rather short and easy proof for the lower bound. Similarly, when F is a normalized starlike function on the unit disk, a lower bound of ||D(f)|| is obtained again.展开更多
A displacement survey method that can be used in fields such as tunnel engineering, huge dam engineering and so on is introduced. According to this method, a series of measuring stations are set along a fold line, and...A displacement survey method that can be used in fields such as tunnel engineering, huge dam engineering and so on is introduced. According to this method, a series of measuring stations are set along a fold line, and a number of bi-direction laser beams and 2-D displacement sensors are used to realize the line and angle displacement measurements to obtain the distortion information of each point. The calculation formulas are given, and the errors are analyzed. This method can also be used in other distortion-measurement fields such as building, bridge and mountain distortion measurements.展开更多
Phlebiopsis gigantea strains registered in the European Union as biocontrol agents against root rot in forests (four from Great Britain and two from Finland) were compared using Ward's method with reference to: (...Phlebiopsis gigantea strains registered in the European Union as biocontrol agents against root rot in forests (four from Great Britain and two from Finland) were compared using Ward's method with reference to: (l) similarity of DNA-random amplified microsatellite (RAMS) ladders, (2) cellulase and peroxidase production and (3) acceleration of dry mass wood loss in Norway spruce The activity of the enzymes was tested in the initial phase of wood decay (30 d after inoculation) and indicated as the most active isolates: VFI0 and FCl5 for cellulase and FC16 and VFI0 for peroxidase production. The assessment of loss of wood six months after inoculation indicated isolate FC 15 as the most active. P. gigantea isolates similar in terms of enzyme activity indicated different patterns ofDNA microsatellite loci. At the same time, DNA-RAMS revealed similarities in isolates with different abilities to produce enzymes. However, some similarities and differences between isolates according to wood decay were found. No plain relationships between molecular characteristics and enzyme activity of the strains tested were observed. The results differentiated activity of tested isolates and suggested benefits of selecting P. gigantea strains for commercial use basing mainly on the assessment of wood loss activity.展开更多
The effect of strain and drawing temperature on the evolution of microstructure and fiber textures of aluminum wiresdrawn at room temperature and cryogenic temperature was investigated by TEM and EBSD observations.The...The effect of strain and drawing temperature on the evolution of microstructure and fiber textures of aluminum wiresdrawn at room temperature and cryogenic temperature was investigated by TEM and EBSD observations.The results show that lowangle boundaries frequency increases and high angle boundaries frequency decreases with strain increasing when the strain is low.Athigh strain,most of grain and dislocation boundaries are parallel to the drawn direction and low angle boundaries frequencydecreases and high angle boundaries frequency increases with strain increasing.The decrease of deformation temperature leads tomicrostructure finer and low angle boundaries frequency increasing.Texture analysis indicates that volume fraction of complextexture component decreases with strain increasing and a mixture of?111?and?100?fiber texture forms at high strain.?111?is stableat low strains but?100?becomes stable at high strain.The decrease of temperature can enhance the stability of?111?orientation athigh strain.展开更多
基金The National Basic Research Program of China (973 Program) (No. 613121010202)
文摘In the traditional unscented Kalman filter(UKF),accuracy and robustness decline when uncertain disturbances exist in the practical system.To deal with the problem,a robust UKF algorithm based on an H-infinity norm is proposed.In Krein space,a robust element is added in the simplified UKF so as to improve the algorithm.The filtering gain is adjusted by the robust element and in this way the performance of the robustness of the filtering algorithm is promoted.In the initial alignment process of the large heading misalignment angle of the strapdown inertial navigation system(SINS),comparative studies are conducted on the robust UKF and the simplified UKF.The simulation results illustrate that compared with the simplified UKF,the robust UKF is more accurate,and the estimation error of heading misalignment decreases from 16.9' to 4.3'.In short,the robust UKF can reduce the sensitivity to the system disturbances resulting in better performance.
基金This project was supported by "the Hundred Leading Scientists Program of the Public Health Sector of Shanghai " (No. 98BR007), and "the National Science Foundation of China" (No. 30370645).
文摘Objective: To study the features of microsatellite alterations on chromosome 8 and their asso- ciation with clinicopathological characteristics of hepatocellular carcinoma (HCC). Methods: Ten highly- polymorphic microsatellite markers on chromosome 8 were selected to be detected for loss of heterozygosity (LOH), microsatellite instability (MSI) and allelic imbalance (AI) in 56 HCC using MegaBACE 500 auto- matic DNA analysis system. Results: LOH was found in 37 of 56 HCC (66.1%) on at least 1 locus, and the top three loci were D8S261(53.5%), D8S1721(52.5%) and D8S1771(52.5%). LOH frequency on D8S277 was signi?cantly higher in cases positive for serum HBsAg than in those negative for HBsAg (P <0.01). Similarly, LOH on D8S261, D8S298 and D8S1733 occurred more frequently in patients with negative HB- sAg than those with positive HBsAg (P <0.01). LOH on D8S298 and D8S1771 was more frequent in those tumors larger than 3 cm in size (P <0.05 or P <0.01). LOH frequencies of D8S1721 were signi?cantly higher in the patients with absent or not intact tumor capsule than in those with intact tumor capsule (P <0.05). LOH on D8S298 and D8S1771 was more frequently detected in tumors with intrahepatic metastasis than in those without intrahepatic metastasis (P <0.01). MSI was found in 12.5% (7/56) cases, and AI was found in 19.6% (11/56), no correlation was found between MSI and AI and clinicopathological character- istics of HCC. Conclusion: Frequent microsatellite alterations on chromosome 8 existed in HCC. LOH, which represents tumor suppressor gene pathway, plays a more important role in hepatocarcinogenesis; MSI representing mismatch repair gene pathway ranks next. LOH at a particula locus is associated with the clinicopathological parameters of human HCC.
文摘Objective To observe therapeutic effects of acupuncture combined with language training on aphasia induced by ischemic apoplexy and investigate the mechanisms. Methods 60 patients were randomly divided into a treatment group treated by acupuncture associated with language training and a control group treated by simple language training. Tongue-acupuncture was applied as the main therapy, and language training included speech organ training, mouth-shape and voice training, spoken language expression training and practical communication ability training. According to Aphosio Bottery of Chinese (ABC), language ex- amination evaluation was made, and event related potential (P300) was detected before and after treatment. Results The therapeutic effect in the treatment group was significantly better than that in the control group (P〈O. 05), and the scores of ABC items including information content, speech fluency, repetition, vocabula- ry denomination, color naming, response denomination, confirmation or negation, acoustic recognition and carrying out instruction in the treatment group were obviously higher than those in the control group (P〈0.05). After one course of treatment, the latencies of N2 and P3 waves in P300 were significantly short- ened and the amplitude of P3 was significantly elevated in the treatment group, compared with those in the control group (P〈0.05). Conclusion Acupuncture combined with language training provided remarkable therapeutic effects in treating cerebral infarction-induced motor aphasia, and it was better than simple lan- guage training. The results of enhancing of the ABC scores including information content, speech fluency, repetition, vocabulary denomination, color naming, response denomination, confirmation or negation, acous- tic recognition and carrying out instruction, and shortening of the latencies of N2 and P3 waves in P300 and ele- vation of P3 amplitude may be taken as the indices for evaluating and anticipating clinical therapeutic effects of the therapy for treating the disease, which may also be some of the mechanisms.
文摘Two plastid division genes, NtFtsZ1 and NtFtsZ2 isolated from Nicotiana tabacum L. were fused with gfp and expressed in Escherichia coli . The regular localizations of full length NtFtsZs∶GFP along the filamentous bacteria indicated that the NtFtsZs could recognize the potential division sites in E. coli and be polymerized with heterogeneous FtsZ from bacteria. The overexpression of NtFtsZs ∶ gfp inhibited the division of host strain cells and resulted in the long filamentous bacterial morphology. These results suggested that eukaryotic ftsZs have similar function to their prokaryotic homologs. Meanwhile, the different deletions of motifs of NtFtsZs are also employed to investigate the functions of these proteins in E. coli . The results showed that the C_terminal domains of NtFtsZs were related to the correct localization of NtFtsZs in E. coli and the N_terminal domains of NtFtsZs were responsible for the polymerization of homogeneous and heterogeneous FtsZ proteins. The significance of these results in understanding the functions of NtFtsZs in plastid division were discussed.
文摘This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantities of this system in equilibrium are obtained.
文摘Using patch clamp whole cell recording techiques, we examined the effects ofIQ_23, a benzyl-isoquinoline derivative with antiarrhythmic activities, on the action potential (AP) andpotassium currents in single guinea pig ventricular myocytes. The results showed that IQ_23 at 10, 30and 100 μmol ·L_-1 slowed the repolarization in AP dose-dependently. The APD_90 were prolonged by15%, 28% and 31% respectively. This effect did not depend on the extracellular Ca^2+. In voltageclamp mode, IQ_23 effectively blocked both the components of the delayed rectifier potassium current(I_k), i.e., I_ks and I_kr. At concentrations of 30 and 100 μmol· L^-1, IQ_23 suppressed I_ks by 21% and 26%and suppressed I_kr by 67% and 86% respectively. But even at 100 μmol·L^-1, IQ_23 had little effect onthe inward rectifier potassium current (I_k1). It is concluded: 1. IQ_23 can dose-dependently prolongAPD in the ventriculas myocytes of guinea pig, the effect does not depend on the extracellular Ca^2+; 2.IQ_23 blocks both I_ks and Ikr in the ventricular myocytes without obvious specificities between them.
基金financially supported in part by the National Key Research and Development Program of China(No.2017YFC0602901)。
文摘This work aimed to quantify the physical and mechanical behavior of three-dimensional microstructures in rocks under uniaxial compression.A high-precision in situ XCT(X-ray transmission computed tomography)technology was applied to investigating the behavior of mineral grains in sandstone:the movement,the rotation deformation,and the principal strains between fault zone and non-fault zone.The results indicate that after unloading,the shear strain of mineral grains is periodic in the radial direction,the strain of mineral grains in the fracture zone is about 30 times of the macro strain of the specimen,which is about 5 times in the non-fracture zone,and the shear strain near the fault zone is larger than the compressive strain,and there is the shear stress concentration feature.
基金Project(51374151)supported by the National Natural Science Foundation of China
文摘The corrosion behavior of the Cu-Ti alloys with different Ti contents in 3.5%(mass fraction)NaCl solution was investigated using electrochemical measurements,immersion tests,mass loss measurements and SEM observation.The results show that Ti dissolved in the Cu matrix changes the corrosion process of the alloys.Pure Cu sample exhibits a typical active–passive-transpassive corrosion behavior.The anodic polarization current densities of the Cu-Ti alloys steadily increase with increasing applied potential,indicating that active dissolution of copper proceeds due to the potential difference in the galvanic coupling of Cu and Ti.The increase of Ti content decreases the corrosion resistance of the Cu-Ti alloys.
文摘Using patch clamp whole cell recording techiques, we examined the effects ofIQ<sub>2</sub>3, a benzyl-isoquinoline derivative with antiarrhythmic activities, on the action potential (AP) andpotassium currents in single guinea pig ventricular myocytes. The results showed that IQ<sub>2</sub>3 at 10, 30and 100 μmol ·L<sub>-</sub>1 slowed the repolarization in AP dose-dependently. The APD<sub>9</sub>0 were prolonged by15%, 28% and 31% respectively. This effect did not depend on the extracellular Ca<sup>2</sup>+. In voltageclamp mode, IQ<sub>2</sub>3 effectively blocked both the components of the delayed rectifier potassium current(I<sub>k</sub>), i.e., I<sub>k</sub>s and I<sub>k</sub>r. At concentrations of 30 and 100 μmol· L<sup>-</sup>1, IQ<sub>2</sub>3 suppressed I<sub>k</sub>s by 21% and 26%and suppressed I<sub>k</sub>r by 67% and 86% respectively. But even at 100 μmol·L<sup>-</sup>1, IQ<sub>2</sub>3 had little effect onthe inward rectifier potassium current (I<sub>k</sub>1). It is concluded: 1. IQ<sub>2</sub>3 can dose-dependently prolongAPD in the ventriculas myocytes of guinea pig, the effect does not depend on the extracellular Ca<sup>2</sup>+; 2.IQ<sub>2</sub>3 blocks both I<sub>k</sub>s and Ikr in the ventricular myocytes without obvious specificities between them.
文摘Cystic dystrophy of the duodenal wall is a rare condition characterized by the development of cysts in heterotopic pancreatic tissue localized in the duodenal wall.A 38-year- old man was admitted to the hospital for abdominal pain and vomiting after food intake.The diagnosis of acute pancreatitis was initially suspected.Abdominal ultrasound examination revealed thickening of the second portion of duodenal wall within which,small cysts(diameter,less than 1 cm)were present in the vicinity of pancreatic head. The head of pancreas appeared enlarged(63 mm×42 mm) and hypoechoic.Upper endoscopy and barium X-ray series were performed revealing a severe circumferential deformation,as well as 4 cm long stenosis of the second portion of the duodenum.CT examination revealed multiple cysts located in an enlarged,thickened duodenal wall with moderate to strong post-contrast enhancement.We suspected that patient had cystic dystrophy of duodenal wall developed in the heterotopic pancreas and diagnosis was confirmed by endoscopic ultrasound(EUS).Endoscopic ultrasound(EUS)revealed circular stenosis from the duodenal bulb onwards.A twenty megahertz mini-prope examination further showed diffuse(intramural)infiltration of duodenal wall limited to the submucosa and muscularis propria of the second portion of duodenum with multiple microcysts within the thickened mucosa and submucosa.Patient was successfully surgically treated and pancreatoduodenectomy was performed.The pathological examination confirmed a diagnosis of cystic dystrophy of a heterotopic pancreas. Endoscopic ultrasonography features allow preoperative diagnosis of cystic dystrophy of a heterotopic pancreas in duodenal wall,with intralumina120 MHz mini probe sonography being more efficient in cases of luminal stenosis.
文摘This paper presents a powerful approach to find the optimal size and location of distributed generation units in a distribution system using GA (Genetic Optimization algorithm). It is proved that GA method is fast and easy tool to enable the planners to select accurate and the optimum size of generators to improve the system voltage profile in addition to reduce the active and reactive power loss. GA fitness function is introduced including the active power losses, reactive power losses and the cumulative voltage deviation variables with selecting weight of each variable. GA fitness function is subjected to voltage constraints, active and reactive power losses constraints and DG size constraint.
文摘Generalist mammalian predators hunt for prey in different ways than raptors,often relying on ambush attack.Such differences in predator behavior can have profound effects on susceptibility of different species of prey to predation,but can also modify the behavior of prey.We investigated susceptibility of common birds to predation by domestic cats Felis catus,relying on an extensive data set on prey abundance and prey availability as determined by standardized bird counts.Susceptibility to cat predation for different species of birds was not significantly correlated with susceptibility to predation by sparrowhawk Accipiter nisus,but with susceptibility to goshawk Accipiter gentilis predation. Susceptibility to goshawk predation was independently predicted by susceptibility to cat and sparrowhawk predation.We cross-validated our estimate of susceptibilityto cat predation by showing that the frequency of birds with tail loss increased strongly with sus-ceptibility to cat predation.Male birds were disproportionately preyed upon,especially if havingsong posts low in the vegetation,and if having short flight distances when singing.Colonially breeding species were less susceptible to predation than solitary species.Bird species with high levels of innate immune defense against bacterial infections had high susceptibility to cat predation.These findings suggest that predation by cats has been an important selection pressure affecting anti-predation behavior,sexual display and immune function in common birds.
基金jointly supported by National Key Project for Basic Research of China (Grant No.2010CB951003)Knowledge Innovation Project of the Chinese Academy of Sciences (Grant No.No.KZCX2-EW-311)National Natural Science Foundation of China (Grant Nos.40631001,41001040,41101066)
文摘Glaciers in the Tomor region of Tianshan Mountains preserve vital water resources. However, these glaciers suffer from strong mass losses in the recent years because of global warming. From 2008 to 2009, a large-scale scientific expedition has been carried out in this region. As an individual reference glacier, the tongue area of Qingbingtan glacier No. 72 was measured by the high precise Real Time Kinematic-Global Position System (RTK-GPS). In this paper, changes of the tongue area of Qingbingtan glacier No.72 has been studied based on topographic map, remote sensing image and the survey during 2008-2009 field campaign. Results indicated that the ice surface-elevation of the tongue area changed - 0.22~0.14 m a-1 from 1964 to 2008. The estimated loss in ice volume was 0.0144-0.009 km3, which represented a ~20 % decrease from the 1964 volume and was equivalent to average annual mass balance of -0.204-0.12 m water equivalent for the tongue area during 1964-2oo8. Terminus retreated by 1852 m, approximately 41 m a-1, with the area reduction of 1.533 km2 (0.034 km2 a-0 from 1964 to 2009. Furthermore, the annual velocity reached to -70 m a-1. Comparing with the other monitored glaciers in the eastern Tianshan Mountains, Qingbingtan glacier No.72 experienced more intensive in shrinkage, which resulted from the combined effects of climate change and glacier dynamic, providing evidence of the response to climatic warming.
基金Foundation item: Supported by the National Natural Science Foundation of China(10826083) Supported by the Zhejiang Provincial Natural Science Foundation of ChinaCD7080080)
文摘Liczberski-Starkov firstfound a lower bound for ||D(f)|| near the origin, where f(z)=(F(z1),√F1(z1)z2,…,√F'(z1)zn)'is the Roper-Suffridge operator on the unit ball Bn in Cn and F is a normalized convex function on the unit disk. Later, Liczberski-Starkov and Hamada-Kohr proved the lower bound holds on the whole unit ball using a complex computation. Here we provide a rather short and easy proof for the lower bound. Similarly, when F is a normalized starlike function on the unit disk, a lower bound of ||D(f)|| is obtained again.
基金The Second Artillery Engineering Project(EP403040101)
文摘A displacement survey method that can be used in fields such as tunnel engineering, huge dam engineering and so on is introduced. According to this method, a series of measuring stations are set along a fold line, and a number of bi-direction laser beams and 2-D displacement sensors are used to realize the line and angle displacement measurements to obtain the distortion information of each point. The calculation formulas are given, and the errors are analyzed. This method can also be used in other distortion-measurement fields such as building, bridge and mountain distortion measurements.
文摘Phlebiopsis gigantea strains registered in the European Union as biocontrol agents against root rot in forests (four from Great Britain and two from Finland) were compared using Ward's method with reference to: (l) similarity of DNA-random amplified microsatellite (RAMS) ladders, (2) cellulase and peroxidase production and (3) acceleration of dry mass wood loss in Norway spruce The activity of the enzymes was tested in the initial phase of wood decay (30 d after inoculation) and indicated as the most active isolates: VFI0 and FCl5 for cellulase and FC16 and VFI0 for peroxidase production. The assessment of loss of wood six months after inoculation indicated isolate FC 15 as the most active. P. gigantea isolates similar in terms of enzyme activity indicated different patterns ofDNA microsatellite loci. At the same time, DNA-RAMS revealed similarities in isolates with different abilities to produce enzymes. However, some similarities and differences between isolates according to wood decay were found. No plain relationships between molecular characteristics and enzyme activity of the strains tested were observed. The results differentiated activity of tested isolates and suggested benefits of selecting P. gigantea strains for commercial use basing mainly on the assessment of wood loss activity.
基金Projects(51471123,51171135)supported by the National Natural Science Foundation of ChinaProjects(2012K07-08,2013KJXX-61)supported by the Natural Science Foundation of Shaanxi Province,ChinaProject(2013JC14)supported by the Industrialization Program of Shaanxi Province,China
文摘The effect of strain and drawing temperature on the evolution of microstructure and fiber textures of aluminum wiresdrawn at room temperature and cryogenic temperature was investigated by TEM and EBSD observations.The results show that lowangle boundaries frequency increases and high angle boundaries frequency decreases with strain increasing when the strain is low.Athigh strain,most of grain and dislocation boundaries are parallel to the drawn direction and low angle boundaries frequencydecreases and high angle boundaries frequency increases with strain increasing.The decrease of deformation temperature leads tomicrostructure finer and low angle boundaries frequency increasing.Texture analysis indicates that volume fraction of complextexture component decreases with strain increasing and a mixture of?111?and?100?fiber texture forms at high strain.?111?is stableat low strains but?100?becomes stable at high strain.The decrease of temperature can enhance the stability of?111?orientation athigh strain.