AIM:To investigate the clinical features and survival of patients treated for cholangiocarcinoma in our institution and to analyze the factors affecting their survival.METHODS:This retrospective cohort study assessed ...AIM:To investigate the clinical features and survival of patients treated for cholangiocarcinoma in our institution and to analyze the factors affecting their survival.METHODS:This retrospective cohort study assessed patients diagnosed with cholangiocarcinoma between January 1997 and December 2007 at the University Malaya Medical Centre in Malaysia.The clinical data and associated outcomes were collected using a structured proforma.RESULTS:Of the 69 patients diagnosed with cholangiocarcinoma,38 (55%) were male;mean patient age was 61 years.Twelve patients (17%) had intrahepatic,38 (55%) had perihilar and 19 (28%) had distal tumors.Only 12 patients underwent curative surgery,including seven R0 resections.Only one patient died within 30 d after surgery.The overall median survival was 4 mo,whereas the median survival of R0 resected patients was 16 mo.The overall 1-,2-and 3-year cumulative survival rates were 67%,17% and 17%,respectively.Survival rates were significantly associated with curative resection (P=0.002),intrahepatic tumor (P=0.003),negative margin status (P=0.013),early tumor stage (P=0.016),higher tumor differentiation (P=0.032) and absence of jaundice (P=0.038).Multivariate analysis showed that tumor location was a significant independent predictor of patient survival.CONCLUSION:Curative,margin-negative resection of early stage,well-differentiated intrahepatic tumors is associated with improved patient survival.展开更多
Statistical analysis of turbulent and gusty characteristics in the atmospheric boundary layer under weak wind period has been carried out.The data used in the analysis were from the multilevel ultrasonic anemometer-th...Statistical analysis of turbulent and gusty characteristics in the atmospheric boundary layer under weak wind period has been carried out.The data used in the analysis were from the multilevel ultrasonic anemometer-thermometers at 47 m,120 m,and 280 m levels on Beijing 325 m meteorological tower.The time series of 3D atmospheric velocity were analyzed by using conventional Fourier spectral analysis and decompose into three parts:basic mean flow(period > 10 min),gusty disturbances(1 min < period < 10 min)and turbulence fluctuations(period < 1 min).The results show that under weak mean wind condition:1)the gusty disturbances are the most strong fluctuations,contribute about 60% kinetic energy of eddy kinetic energy and 80% downward flux of momentum,although both the eddy kinetic energy and momentum transport are small in comparison with those in strong mean wind condition;2)the gusty wind disturbances are anisotropic;3)the gusty wind disturbances have obviously coherent structure,and their horizontal and vertical component are negatively correlated and make downward transport of momentum more effectively;4)the friction velocities related to turbulence and gusty wind are approximately constant with height in the surface layer.展开更多
Daily precipitation analyses for 659 Chinese meteorological stations from 1951 to 2010 show that the rapid urbanization may have triggered the significant increase of heavy rainfall in China. During the last decades, ...Daily precipitation analyses for 659 Chinese meteorological stations from 1951 to 2010 show that the rapid urbanization may have triggered the significant increase of heavy rainfall in China. During the last decades, HRAs （Heavy Rainfall Amounts）, HRDs （Heavy Rainfall Days） and HRI （Heavy Rainfall Intensity） in China have increased. Impressively, the upward trends are not randomly observed among stations, but of robust consistency with quite large regional scale over large widely and significantly. Compared to the 1950s, the HRA, HRD, and HRI increased by 68.71%, 60.15% and 11.52% during the 2000s. The significant increase of accumulative heavy rainfall appears firstly in the southeastern coasts in the early period, and then gradually expands to the central, southwest, north and northeast China. Rapid urbanization is very likely the main cause of large-scale heavy rainfall increase in China. The urbanization indicators including the industrial production output （GDP2）, UP （Urban Population） and annual average HDs （Haze Days） are in good agreement with the heavy rainfall variations, and these indicators can statistically explain the variance of HRA, HRD and HRI by 61.54%, 58.48% and 65.54%, respectively. Meanwhile, the explained variance by leading climate indices including WPSH （Western Pacific Subtropical High）, ENSO （El Nino-Southern Oscillation）, AMO （Atlantic Multi-decadal Oscillation） and AAO （Antarctic Oscillation） are respectively 24.30%, 26.23% and 21.92%, being only about 1/3 of the urbanization-related variance. Panel data analysis of county-level total population and annual average visibility days less than 10 km also show that these two indicators have significant correlation with decadal HRA, HRD ＆ HRI and the spatial correlation coefficient increases gradually with time. These consistent temporal and spatial features strongly suggest that rapid urbanization most likely triggered the steady increase of heavy rainfall over China during the recent decades.展开更多
The communication in the physical layer between an interrogator and a tag of a passive Radio Frequency Identification （RFID） system operating between 860-960 MHz is defined by the Gen 2 protocol. The tag can be cons...The communication in the physical layer between an interrogator and a tag of a passive Radio Frequency Identification （RFID） system operating between 860-960 MHz is defined by the Gen 2 protocol. The tag can be considered a remote executing unit or a computer that executes instructions from the Gen 2 protocol. The selection of the parameter and command configuration within the protocol limitations is critical especially if the time available for the memory operations in a passive RFID system is limited. An effort is made to map the operation of the tag not in its states of operation as elaborately explained in the protocol but rather in its elementary format. The research reported in this article identifies all the parameters that affect the dynamic operation of the tag. The operation is further divided into singulation, read and write; identifying the significant parameters in each case. The choices of the different commands that can be adopted to perform identical operations on the tag are analyzed. The elements to consider in selecting the optimum command configuration are described. The impact of the different parameter and command configuration on the singulation, read and write time is calculated and recorded using a tested Gen 2 simulator program.展开更多
Objective： To investigate the epidemiological characteristics of eye injuries sustained by military personnel in Chinese army. Methods： Eleven military evacuation hospitals located in different regions were selecte...Objective： To investigate the epidemiological characteristics of eye injuries sustained by military personnel in Chinese army. Methods： Eleven military evacuation hospitals located in different regions were selected for this study. We reviewed all the medical records of eye injuries sustained by military personnel between January 2005 and December 2009. Patients＇ information was collected. All data were put into database and analyzed statistically. Results： Totally there were 415 inpatients with eye injuries （442 eyes） and their mean age was 24.40 years. Eye injury accounts for 13.51% of all eye diseases in this study. From 2006 to 2009, the number of eye injury increased gradually. Among them, 175 （42.17%） were injured in leisure time, and 145 （34.94%） in working time. Twenty-two （5.30%） patients had an eye surgery or history of eye disease before injury. In all, 246 patients （59.28%） were sent to evacuation hospital within 24 hours and 64 （56.64%） underwent surgeries in 24 hours after injury. There were 389 patients （93.73%） hospitalized for 1 time. Visual acuities of 187 eyes （42.31%） were grade 1 （≥ 20/40） after injury. When discharge, 349 eyes （78.96%） obtained a visual acuity of grade 1. Conclusion： Eye injury has a very frequent incidence in Chinese army and much more attention should be paid to prevent it.展开更多
文摘AIM:To investigate the clinical features and survival of patients treated for cholangiocarcinoma in our institution and to analyze the factors affecting their survival.METHODS:This retrospective cohort study assessed patients diagnosed with cholangiocarcinoma between January 1997 and December 2007 at the University Malaya Medical Centre in Malaysia.The clinical data and associated outcomes were collected using a structured proforma.RESULTS:Of the 69 patients diagnosed with cholangiocarcinoma,38 (55%) were male;mean patient age was 61 years.Twelve patients (17%) had intrahepatic,38 (55%) had perihilar and 19 (28%) had distal tumors.Only 12 patients underwent curative surgery,including seven R0 resections.Only one patient died within 30 d after surgery.The overall median survival was 4 mo,whereas the median survival of R0 resected patients was 16 mo.The overall 1-,2-and 3-year cumulative survival rates were 67%,17% and 17%,respectively.Survival rates were significantly associated with curative resection (P=0.002),intrahepatic tumor (P=0.003),negative margin status (P=0.013),early tumor stage (P=0.016),higher tumor differentiation (P=0.032) and absence of jaundice (P=0.038).Multivariate analysis showed that tumor location was a significant independent predictor of patient survival.CONCLUSION:Curative,margin-negative resection of early stage,well-differentiated intrahepatic tumors is associated with improved patient survival.
基金supported by the national natural Science Foundation of China(40830103 and 41375018)the national Basic Research Program of China(2010CB951804)the Research Program of the Chinese Academy of Sciences(XDA10010403)
文摘Statistical analysis of turbulent and gusty characteristics in the atmospheric boundary layer under weak wind period has been carried out.The data used in the analysis were from the multilevel ultrasonic anemometer-thermometers at 47 m,120 m,and 280 m levels on Beijing 325 m meteorological tower.The time series of 3D atmospheric velocity were analyzed by using conventional Fourier spectral analysis and decompose into three parts:basic mean flow(period > 10 min),gusty disturbances(1 min < period < 10 min)and turbulence fluctuations(period < 1 min).The results show that under weak mean wind condition:1)the gusty disturbances are the most strong fluctuations,contribute about 60% kinetic energy of eddy kinetic energy and 80% downward flux of momentum,although both the eddy kinetic energy and momentum transport are small in comparison with those in strong mean wind condition;2)the gusty wind disturbances are anisotropic;3)the gusty wind disturbances have obviously coherent structure,and their horizontal and vertical component are negatively correlated and make downward transport of momentum more effectively;4)the friction velocities related to turbulence and gusty wind are approximately constant with height in the surface layer.
文摘Daily precipitation analyses for 659 Chinese meteorological stations from 1951 to 2010 show that the rapid urbanization may have triggered the significant increase of heavy rainfall in China. During the last decades, HRAs （Heavy Rainfall Amounts）, HRDs （Heavy Rainfall Days） and HRI （Heavy Rainfall Intensity） in China have increased. Impressively, the upward trends are not randomly observed among stations, but of robust consistency with quite large regional scale over large widely and significantly. Compared to the 1950s, the HRA, HRD, and HRI increased by 68.71%, 60.15% and 11.52% during the 2000s. The significant increase of accumulative heavy rainfall appears firstly in the southeastern coasts in the early period, and then gradually expands to the central, southwest, north and northeast China. Rapid urbanization is very likely the main cause of large-scale heavy rainfall increase in China. The urbanization indicators including the industrial production output （GDP2）, UP （Urban Population） and annual average HDs （Haze Days） are in good agreement with the heavy rainfall variations, and these indicators can statistically explain the variance of HRA, HRD and HRI by 61.54%, 58.48% and 65.54%, respectively. Meanwhile, the explained variance by leading climate indices including WPSH （Western Pacific Subtropical High）, ENSO （El Nino-Southern Oscillation）, AMO （Atlantic Multi-decadal Oscillation） and AAO （Antarctic Oscillation） are respectively 24.30%, 26.23% and 21.92%, being only about 1/3 of the urbanization-related variance. Panel data analysis of county-level total population and annual average visibility days less than 10 km also show that these two indicators have significant correlation with decadal HRA, HRD ＆ HRI and the spatial correlation coefficient increases gradually with time. These consistent temporal and spatial features strongly suggest that rapid urbanization most likely triggered the steady increase of heavy rainfall over China during the recent decades.
文摘The communication in the physical layer between an interrogator and a tag of a passive Radio Frequency Identification （RFID） system operating between 860-960 MHz is defined by the Gen 2 protocol. The tag can be considered a remote executing unit or a computer that executes instructions from the Gen 2 protocol. The selection of the parameter and command configuration within the protocol limitations is critical especially if the time available for the memory operations in a passive RFID system is limited. An effort is made to map the operation of the tag not in its states of operation as elaborately explained in the protocol but rather in its elementary format. The research reported in this article identifies all the parameters that affect the dynamic operation of the tag. The operation is further divided into singulation, read and write; identifying the significant parameters in each case. The choices of the different commands that can be adopted to perform identical operations on the tag are analyzed. The elements to consider in selecting the optimum command configuration are described. The impact of the different parameter and command configuration on the singulation, read and write time is calculated and recorded using a tested Gen 2 simulator program.
文摘Objective： To investigate the epidemiological characteristics of eye injuries sustained by military personnel in Chinese army. Methods： Eleven military evacuation hospitals located in different regions were selected for this study. We reviewed all the medical records of eye injuries sustained by military personnel between January 2005 and December 2009. Patients＇ information was collected. All data were put into database and analyzed statistically. Results： Totally there were 415 inpatients with eye injuries （442 eyes） and their mean age was 24.40 years. Eye injury accounts for 13.51% of all eye diseases in this study. From 2006 to 2009, the number of eye injury increased gradually. Among them, 175 （42.17%） were injured in leisure time, and 145 （34.94%） in working time. Twenty-two （5.30%） patients had an eye surgery or history of eye disease before injury. In all, 246 patients （59.28%） were sent to evacuation hospital within 24 hours and 64 （56.64%） underwent surgeries in 24 hours after injury. There were 389 patients （93.73%） hospitalized for 1 time. Visual acuities of 187 eyes （42.31%） were grade 1 （≥ 20/40） after injury. When discharge, 349 eyes （78.96%） obtained a visual acuity of grade 1. Conclusion： Eye injury has a very frequent incidence in Chinese army and much more attention should be paid to prevent it.
