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抗冻混凝土配合比正交设计方案
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作者 王宝民 《黑龙江水利科技》 2006年第4期26-27,共2页
采用正交设计方法,根据抗冻混凝土配合比的参数因素,评定指标确定的水平数,确定验证配合比设计是否合理的试验组数,进而规定了大数量混凝土的最少试验数量,同时规定的最少试验数并不影响混凝土质量的评定。
关键词 正交设计 因素数 水平数 抗冻混凝土 配合比设计 最少试验组数
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Grain Crop Fertilization Status and Factors Influencing Farmers' Decision Making on Fertilizer Use: China Case Study 被引量:5
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作者 闫湘 金继运 梁鸣早 《Agricultural Science & Technology》 CAS 2016年第10期2394-2398,2440,共6页
[Objective] China is the world's largest fertilizer consumer. Fertilizer plays an important role in maintaining China's food security. Along with population and economic growth, overuse of fertilizers has caused ser... [Objective] China is the world's largest fertilizer consumer. Fertilizer plays an important role in maintaining China's food security. Along with population and economic growth, overuse of fertilizers has caused serious environmental problems, such as soil acidification, decline in soil organic carbon, and agricultural non-point source pollution. This study aimed to analyze the factors influencing farmers" decision making on fertilizer use, and provide policy recommendations on ways to affect fertilization. [Method] An econometric model reflecting fertilization of rural households was estimated from a survey distributed to 1 043 households randomly selected from 19 provinces in China. [Result] Results of the study showed that education years of fertilizer decision maker, fertilizer quality, organic fertilizer application, fertilizer price, and agricultural product price had significant effects on the fertilizer application rate at 1% level. Soil nutrient affected the fertilizer application rate at 10% level. [Conclusion] Policies aimed at improving the reasonable use of fertilizer should focus on the regulation of chemical fertilizer price, foundation of the organic-inorganic fertilizer system, soil testing, formulated fertilization, and agricultural extension service. 展开更多
关键词 FARMERS Fertilizer application rate Influencing factors Double logarith- mic model
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Dynamics of Slope Runoff and Soil Erosion of Different Forest Types in Karst Depression 被引量:6
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作者 张喜 连宾 +2 位作者 尹洁 吴永波 崔迎春 《Agricultural Science & Technology》 CAS 2010年第3期166-171,共6页
[Objective] The research was aimed to study the dynamics of slope runoff and soil erosion in different forest types in karst depression.[Method] Precipitation observation sites at the bottom of karst depression and ru... [Objective] The research was aimed to study the dynamics of slope runoff and soil erosion in different forest types in karst depression.[Method] Precipitation observation sites at the bottom of karst depression and runoff observation sites in different forest types were established to monitor regularly the main indices changes of runoff and soil erosion at fixed position in 4 years.[Result] The surface runoff of different forest types appeared singer peak from February to November,with lowest valley from June to July.The runoff coefficient appeared double peaks from February to May and from July to September.The changing coefficient of runoff appeared three peaks from March to April,from July to August and from September to November.The silt concentration appeared one peak from March to May and The erosion modulus appeared double peaks from March to May and from June to August.Runoff showed annually reduced trend with the growth of forests and the development of vegetation layer's structure.There was a positive correlation between the runoff and its silt concentration in different forest types.Precipitation and evaporation had notable positive correlation with the runoff,and similar correlation but not marked with silt concentration.The fitting analysis results of surface runoff and erosion modulus showed that rocky desertification intensified the unevenness of surface runoff and increased the surface runoff and erosion modulus.The penetrability of surface soil in new planted forest was lower than that in young forest,and that in surface soil of different forest types was higher than in bottom soil.[Conclusion] The research provided theoretical basis for the biological management technologies of water and soil conservation and the control of karst rocky desertification in karst regions. 展开更多
关键词 Karst depression Forest types RUNOFF Erosion modulus Affecting factors
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Generating test cases for software configuration testing 被引量:2
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作者 聂长海 徐宝文 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期26-30,共5页
Software configuration testing is used to test a piece of software with all kinds of hardware to ensure that it can run properly on them. This paper generates test cases for configuration testing with several common m... Software configuration testing is used to test a piece of software with all kinds of hardware to ensure that it can run properly on them. This paper generates test cases for configuration testing with several common methods, such as multiple single-factor experiments, uniform design, and orthogonal experiment design used in other fields. This paper analyzes their merits and improves the orthogonal experiment design method with pairwise testing, and decreases the testing risk caused by incomplete testing with a method of multiple-factors-covering. It presents a simple factor cover method which can cover all the factors and pairwise combinations to the greatest degree. Some comparisons of these methods are made on the aspects of test suite scale, coverage, and usability, etc.. 展开更多
关键词 Computer hardware TESTING
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Emission Characteristics of Soil Nitrous Oxide from Typical Greenhouse Vegetable Fields in North China
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作者 徐钰 刘兆辉 +5 位作者 魏建林 石璟 谭德水 王梅 李国生 江丽华 《Agricultural Science & Technology》 CAS 2017年第3期438-442,共5页
To make clear the emission characteristics of soil N20 from typical green- house vegetable fields in North China, an experiment was conducted in greenhouse tomato field in Shouguang city, Shandong province, China's ... To make clear the emission characteristics of soil N20 from typical green- house vegetable fields in North China, an experiment was conducted in greenhouse tomato field in Shouguang city, Shandong province, China's "Home of Vegetables". The N2O fluxes were observed in four experimental treatments, as follows: none N fertilizer (CK), single organic fertilizer (OM), conventional fertilization (FP) and opti- mized and reduced nitrogen fertilization (OPT), by a close chamber-gas chromato- graph method. The effects of different fertilization treatments on N2O emission and tomato yield were analyzed. The results showed that following the fertilization and ir- rigation, the pulsed emissions of N2O were measured. The N2O emission peak ap- peared after basal fertilizer application and irrigation and could be maintained for about 20 days. While the N2O emission peak caused by topdressing was smaller and last only 3-5 days. The statistical analysis showed that the N2O fluxes were affected by air temperature, soil temperature and WFPS at soil depth of 3 cm. The total contents of soil N2O fluxes had significant differences among experimental groups. The total content orderly was FP of 14. 77 kg/hm^2, OPT of 9. 73 kg/hm^2, OM of 6.84 kg/hm^2 and CK of 2.37 kg/hm^2. The N~:~ emission coefficient ranged from 0.83%-1.10%,which was close to or more than the recommended value (1.0%) by IPCC. Compared with the FP treatment, the tomato yield in OPT treatment, whose application rate of chemical N fertilizer decreased by about 60%, increased by 2.2%. Under the current management measures, the reasonable reduction on ap- plicaUon rate of organic manure and chemical nitrogen fertilizer could effectively re- duce the N=O emissions in greenhouse vegetable fields. 展开更多
关键词 Greenhouse vegetable field N2O emission characteristic Influencingfactor Emission coefficient Tomato yield
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Spatio-temporal Difference and Influencing Factors of Environmental Adaptability Measurement of Human-sea Economic System in Liaoning Coastal Area 被引量:6
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作者 LI Bo SHI Zhaoyuan TIAN Chuang 《Chinese Geographical Science》 SCIE CSCD 2018年第2期313-324,共12页
Adaptability theory is an important tool to analyze the degree, mechanism and process of interaction between human and environment, which provides a new perspective for the research of sustainability assessment. Based... Adaptability theory is an important tool to analyze the degree, mechanism and process of interaction between human and environment, which provides a new perspective for the research of sustainability assessment. Based on the entropy weight-TOPSIS method and the panel Tobit model from the perspective of adaptability, spatio-temporal difference and influencing factors of environmental adaptability assessment of human-sea economic system in Liaoning coastal area was measured by using the city panel data from 2000 to 2014. The results indicate that: 1) The environmental adaptability of human-sea economic system in Liaoning coastal area rose slowly from 2000 to 2014, the developing trend of each city was linearly related, and Dalian was in a leading position. 2) The different adaptability elements and adaptability subsystem show polarization phenomenon and completely different regional evolution characteristics. The adaptability of human-sea environment system and human-sea economic system rose slowly and had the characteristics of linear relationship, and the adaptability of human-sea environment system is the main reason for the difference of environmental adaptability of human-sea economic system. 3) Science and technology, environmental management, marine economic development level, port construction are the driving factors of the healthy development of environmental adaptability of urban human-sea economic system. 展开更多
关键词 human-sea economic system ADAPTABILITY human-sea environment system influencing factors Liaoning coastal area
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Mining Weights of Land Evaluation Factors Based on Cloud Model and Correlation Analysis 被引量:17
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作者 HU Shiyuan LI Deren +1 位作者 LIU Yaolin LI Deyi 《Geo-Spatial Information Science》 2007年第3期218-222,共5页
The veracity of land evaluation is tightly related to the reasonable weights of land evaluation fac- tors. By mapping qualitative linguistic words into a fine-changeable cloud drops and translating the uncertain facto... The veracity of land evaluation is tightly related to the reasonable weights of land evaluation fac- tors. By mapping qualitative linguistic words into a fine-changeable cloud drops and translating the uncertain factor conditions into quantitative values with the uncertain illation based on cloud model, and then, inte- grating correlation analysis, a new way of figuring out the weight of land evaluation factors is proposed. It may solve the limitations of the conventional ways. 展开更多
关键词 cloud models correlation analysis land evaluation factor weight data mining
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Impacts of Climatic Factors on Runoff Coefficients in Source Regions of the Huanghe River 被引量:12
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作者 CHEN Liqun LIU Changming +1 位作者 LI Yanping WANG Guoqiang 《Chinese Geographical Science》 SCIE CSCD 2007年第1期47-55,共9页
Runoff coefficients of the source regions of the Huanghe River in 1956-2000 were analyzed in this paper. In the 1990s runoff of Tangnaihai Hydrologic Station of the Huanghe River experienced a serious decrease, which ... Runoff coefficients of the source regions of the Huanghe River in 1956-2000 were analyzed in this paper. In the 1990s runoff of Tangnaihai Hydrologic Station of the Huanghe River experienced a serious decrease, which had attracted considerable attention. Climate changes have important impact on the water resources availability. From the view of water cycling, runoff coefficients are important indexes of water resources in a particular catchment. Kalinin baseflow separation technique was improved based on the characteristics of precipitation and streamflow. After the separation of runoff coefficient (R/P), baseflow coefficient (Br/P) and direct runoff coefficient (Dr/P) were estimated. Statistic analyses were applied to assessing the impact of precipitation and temperature on runoff coefficients (including Dr/P, Br/P and R/P). The results show that in the source regions of the Huanghe River, mean annual baseflow coefficient was higher than mean annual direct runoff coefficient. Annual runoff coefficients were in direct proportion to annual precipitation and in inverse proportion to annual mean temperature. The decrease of runoff coefficients in the 1990s was closely related to the decrease in precipitation and increase in temperature in the same period. Over different sub-basins of the source regions of the Huanghe River, runoff coefficients responded differently to precipitation and temperature. In the area above Jimai Hydrologic Station where annual mean temperature is -3.9℃, temperature is the main factor influencing the runoff coefficients. Runoff coefficients were in inverse relation to temperature, and precipitation had nearly no impact on runoff coefficients. In subbasin between Jimai and Maqu Hydrologic Station Dr/P was mainly affected by precipitation while R/P and Br/P were both significantly influenced by precipitation and temperature. In the area between Maqu and Tangnaihai hydrologic stations all the three runoff coefficients increased with the rising of annual precipitation, while direct runoff coefficient was inversely proportional to temperature. In the source regions of the Huanghe River with the increase of average annual temperature, the impacts of temperature on runoff coefficients become insignificant. 展开更多
关键词 source regions of the Huanghe River runoff coefficient PRECIPITATION TEMPERATURE
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Bombyx mori Pyridoxal Kinase cDNA Cloning and Enzymatic Characterization 被引量:1
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作者 石瑞君 张剑韵 +1 位作者 江昌俊 黄龙全 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第8期683-690,共8页
Pyridoxal kinase (PLK) (EC 2.7.1.35) catalyzes the ATP-dependent phosphorylation of pyridoxal, generating pyridoxal-5'-phosphate (PLP), an important cofactor for many enzymatic reactions. Bombyx mori, similar t... Pyridoxal kinase (PLK) (EC 2.7.1.35) catalyzes the ATP-dependent phosphorylation of pyridoxal, generating pyridoxal-5'-phosphate (PLP), an important cofactor for many enzymatic reactions. Bombyx mori, similar to mammals, relies on a nutritional source of vitamin B6 to synthesize PLP. This article describes how a cDNA encoding PLK was cloned from Bombyx mori using the PCR method (GenBank accession number: DQ452397). The cDNA has an 894 bp open reading frame and encodes a protein of 298 amino acid residues with a molecular mass of 33.1 k.Da. The amino acid sequence shares 48.6% identity with that of human PLK, and it also contains signature conserved motifs of the PLK family. However, the protein is 10 or more amino acids shorter than the PLK from mammals and plants, and several amino acid residues conserved in the PLK from mammals and plants are changed in the protein. The cDNA cloned was expressed successfully in Escherichia coli using the T7 promoter/T7 RNA polymerase expression system, and the crude extracts containing the expressed product were found to have strong PLK enzymatic activity with a value of 30 nmol/min/mg, confirming that the cDNA encodes the functional PLK of Bombyx mori. This is the first identification of a gene encoding PLK in insects. 展开更多
关键词 pyridoxal kinase Bombyx mori (silkworm) pyridoxal-5'-phosphate (PLP) vitamin B6 metabolism genomic database
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Prime Factorization in the Duality Computer 被引量:8
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作者 WANG Wan-Ying SHANG Bin +1 位作者 WANG Chuan LONG Gui-Lu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期471-473,共3页
We give algorithms to factorize large integers in the duality computer. We provide three duality algorithms for factorization based on a naive factorization method, the Shor algorithm in quantum computing, and the Fer... We give algorithms to factorize large integers in the duality computer. We provide three duality algorithms for factorization based on a naive factorization method, the Shor algorithm in quantum computing, and the Fermat's method in classical computing. All these algorithms may be polynomial in the input size. 展开更多
关键词 duality computer prime factorization Fermat's method
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Quantitative analysis on influencing factors for interface propagation-based thermal conductivity measurement method during solid-liquid transition 被引量:1
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作者 ZHOU Tian MA Xiao-yi +1 位作者 LIU Xu LI Yuan 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第8期2041-2055,共15页
The recently proposed interface propagation-based method has shown its advantages in obtaining the thermal conductivity of phase change materials during solid-liquid transition over conventional techniques. However, i... The recently proposed interface propagation-based method has shown its advantages in obtaining the thermal conductivity of phase change materials during solid-liquid transition over conventional techniques. However, in previous investigation, the analysis on the measurement error was qualitative and only focused on the total effects on the measurement without decoupling the influencing factors. This paper discusses the effects of influencing factors on the measurement results for the interface propagation-based method. Numerical simulations were performed to explore the influencing factors, namely model simplification, subcooling and natural convection, along with their impact on the measurement process and corresponding measurement results. The numerical solutions were provided in terms of moving curves of the solid-liquid interface and the predicted values of thermal conductivity. Results indicated that the impact of simplified model was strongly dependent on Stefan number of the melting process. The degree of subcooling would lead to underestimated values for thermal conductivity prediction. The natural convection would intensify the heat transfer rate in the liquid region, thereby overestimating the obtained results of thermal conductivity. Correlations and experimental guidelines are provided. The relative errors are limited in ±1.5%,±3%and ±2% corresponding to the impact of simplified model, subcooling and natural convection, respectively. 展开更多
关键词 phase change material thermal conductivity measurement influencing factor interface propagation-based method numerical simulation
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A New CMOS Image Sensor with a High Fill Factor and the Dynamic Digital Double Sampling Technique
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作者 刘宇 王国裕 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第2期313-317,共5页
A single CMOS image sensor based on a 0.35μm process along with its design and implementation is introduced. The architecture of an active pixel sensor is used in the chip. The fill factor of a pixel cell can reach 4... A single CMOS image sensor based on a 0.35μm process along with its design and implementation is introduced. The architecture of an active pixel sensor is used in the chip. The fill factor of a pixel cell can reach 43%,higher than the traditional factor of 30%. Moreover, compared with the conventional method whose fixed pattern noise (FPN) is around 0.5%, a dynamic digital double sampling technique is developed, which possesses simpler circuit architecture and a better FPN suppression outcome. The CMOS image sensor chip is implemented in the 0.35μm mixed signal process of a Chartered by MPW. The experimental results show that the chip operates welt,with an FPN of about 0.17%. 展开更多
关键词 active pixel CMOS image sensor fill factor dynamic digital double sampling fixed pattern noise
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Human Settlement Analysis Based on Multi-temporal Remote Sensing Data: A Case Study of Xuzhou City, China 被引量:5
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作者 ZHU Jishuai TIAN Shufang +1 位作者 TAN Kun DU Peijun 《Chinese Geographical Science》 SCIE CSCD 2016年第3期389-400,共12页
To evaluate urban human settlement, we propose a human settlement environment development index(HSEDI) model by choosing vegetation coverage, land surface temperature, impervious surfaces, slope, wetness, and water co... To evaluate urban human settlement, we propose a human settlement environment development index(HSEDI) model by choosing vegetation coverage, land surface temperature, impervious surfaces, slope, wetness, and water condition as the evaluation factors. We applied the proposed model to Xuzhou City, Jiangsu Province, China. Landsat-5 Thematic Mapper(TM) images from 1998 to 2010 and digital elevation model(DEM) data with a 30-m resolution were used to calculate the values of the six evaluation factors. The HSEDI value in Xuzhou City was found to be between 2.24 and 8.10 from 1998 to 2010, and it was further divided into five levels, uninhabitable, moderately uninhabitable, generally inhabitable, moderately inhabitable, and inhabitable. The best HSEDI value was in 2007. The generally inhabitable region was about 100.98 km^2, covering 30.87% of the total area in 2007; the moderately inhabitable region was about 170.58 km2 covering 52.15% of the total area; the inhabitable region was about 32.03 km^2, covering 9.79% of the total area; the percentage of the uninhabitable region was zero; and that of the moderately uninhabitable region was very small, less than 1.00%. Moreover, we analyzed the habitability in the respect of spatial patterns and change detection. Results show that the degraded regions of habitability quality are mainly located in the urban fringe and the improved regions are mainly located in the main urban and rural areas. Reason for the degraded habitability quality is the rapid progress of urbanization. However, the increase in urban green spaces and the construction of the main urban area promoted the improved habitability quality. Besides, we further analyzed socio-economic and socio-demographic data to confirm the results of the habitability analysis. The results indicate that the human settlement in Xuzhou City is in a satisfactory condition, but some efforts should be made to control the possible uninhabitable and moderately uninhabitable regions, and to improve the quality of the generally inhabitable regions. 展开更多
关键词 habitability human settlement Landsat human settlement environment development index(HSEDI) model
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Determining Topographic Shielding from Digital Elevation Models for Cosmogenic Nuclide Analysis:a GIS Approach and Field Validation 被引量:8
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作者 LI Ying-kui 《Journal of Mountain Science》 SCIE CSCD 2013年第3期355-362,共8页
Topographic shielding of cosmic radiation flux is a key parameter in using cosmogenic nuclides to determine surface exposure ages or erosion rates. Traditionally, this parameter is measured in the field and uncertaint... Topographic shielding of cosmic radiation flux is a key parameter in using cosmogenic nuclides to determine surface exposure ages or erosion rates. Traditionally, this parameter is measured in the field and uncertainty and/or inconsistency may exist among different investigators. This paper provides an ArcGIS python code to determine topographic shielding factors using digital elevation models (DEMs). This code can be imported into ArcGIS as a geoprocessing tool with a user-friendly graphical interface. The DEM-derived parameters using this method were validated with field measurements in central Tian Shan. Results indicate that DEM-derived shielding factors are consistent with field-measured values. It provides a valuable tool to save fieldwork efforts and has the potential to provide consistent results for different regions in the world to facilitate the comparison of cosmogenie nuclide results. 展开更多
关键词 Cosmogenic nuclides Topographicshielding ARCGIS PYTHON Digital elevation models(DEMs)
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Analysis of Three-dimensional Crack Propagation by Using Displacement Discontinuity Method 被引量:3
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作者 王飞 黄醒春 《Journal of Donghua University(English Edition)》 EI CAS 2010年第6期835-840,共6页
A technique for modelling of three-dimensional(3D)quasi-statically propagating cracks in elastic bodies by the displacement discontinuity method(DDM)was described.When the crack is closed,the Mohr-coulomb rule on the ... A technique for modelling of three-dimensional(3D)quasi-statically propagating cracks in elastic bodies by the displacement discontinuity method(DDM)was described.When the crack is closed,the Mohr-coulomb rule on the two contacted surfaces of the crack must be satisfied.A simple iterative method was adopted in order to consider three different states of cracks.Under the assumption that the advance of the point on the crack front would occur only in the normal plane which is through this edge point,the maximum energy release rate criterion is modified to be used as the criterion for the crack growth.With discretization,the process of crack propagation can be seen as the advance of the vertices of the crack front.The program MCP3D was developed based on these theories to simulate the 3D quasi-static crack propagation.A numerical example of a penny-shaped crack subject to tension and compression in an infinite elastic media was analyzed with MCP3D,and the results in comparison with others' show that the present method for 3D crack propagation is effective. 展开更多
关键词 three-dimensional(3D)crack propagation displacement discontinuity method stress intensity factor(SIF) numerical simulation
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Henry's Law constant for phosphine in seawater:determination and assessment of influencing factors 被引量:2
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作者 付梅 俞志明 +1 位作者 卢光远 宋秀贤 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第4期860-866,共7页
The Henry's Law constant (k) for phosphine in seawater was determined by multiple phase equilibration combined with headspace gas chromatography. The effects of pH, temperature, and salinity on k were studied. The ... The Henry's Law constant (k) for phosphine in seawater was determined by multiple phase equilibration combined with headspace gas chromatography. The effects of pH, temperature, and salinity on k were studied. The k value for phosphine in natural seawater was 6.415 at room temperature (approximately 23℃). This value increases with increases in temperature and salinity, but no obvious change was observed at different pH levels. At the same temperature, there was no significant difference between the k for phosphine in natural seawater and that in artificial seawater. This implies that temperature and salinity are major determining factors for k in marine environment. Double linear regression with Henry's Law constants for phosphine as a function of temperature and salinity confirmed our observations. These results provide a basis for the measurement of trace phosphine concentrations in seawater, and will be helpful for future research on the status of phosphine in the oceanic biogeochemical cycle of phosphorus. 展开更多
关键词 PHOSPHINE Henry's Law constant seawater influencing factors multiple phase equilibration
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Factors determining delay in relaparotomy for anastomotic leakage after colorectal resection 被引量:19
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作者 A Doeksen PJ Tanis +2 位作者 BC Vrouenraets JJB Lanschot van WF Tets van 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第27期3721-3725,共5页
AIM: To analyze the time interval (‘delay') between the first occurrence of clinical parameters associated with anastomotic leakage alter colorectal resection and subsequent relaparotomy. METHODS: In 36 out of 2... AIM: To analyze the time interval (‘delay') between the first occurrence of clinical parameters associated with anastomotic leakage alter colorectal resection and subsequent relaparotomy. METHODS: In 36 out of 289 consecutive patients with colorectal anastomosis, leakage was confirmed at relaparotomy. The medical records of these patients were retrospectively analysed and type and time of appearance of clinical parameters suggestive of anastomotic leakage were recorded. These parameters included heart rate, body temperature, local or generalized peritoneal reaction, leucocytosis, ileus and delayed gastric emptying. Factors influencing delay of relaparotomy and consequences of delayed recognition and treatment were determined. RESULTS: First documentation of at least one of the predefined parameters for anastomotic leakage was alter a median interval of 4 ± 1.7 d alter the operation. The median number of days between first parameter(s) associated with leakage and relaparotomy was 3.5 ± 5.7 d. The time interval between the first signs of leakage and relaparotomy was significantly longer when a weekend was included (4.2 d vs 2.4 d, P = 0.021) or radiological evaluation proved to be false-negative (8.1 d vs 3.5 d, P = 0.007). No significant association between delay and number of additional relaparotomies, hospital stay or mortality could be demonstrated.CONCLUSION: An intervening weekend and negative diagnostic imaging reports may contribute to a delay in diagnosis and relaparotomy for anastomotic leakage. That delay was more than two days in two-thirds of the patients. 展开更多
关键词 Colorectal surgery ANASTOMOSIS LEAKAGE Clinical parameter DELAY
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Effects of spatio-temporal and environmental factors on distribution and abundance of wintering anchovy Engraulis japonicus in central and southern Yellow Sea 被引量:2
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作者 牛明香 金显仕 +1 位作者 李显森 王俊 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第3期565-575,共11页
We investigated the spatio-temporal and environmental factors that affect the distribution and abundance of wintering anchovy and quantifi es the infl uences of these factors. Generalized additive models(GAMs) were de... We investigated the spatio-temporal and environmental factors that affect the distribution and abundance of wintering anchovy and quantifi es the infl uences of these factors. Generalized additive models(GAMs) were developed to examine the variation in species distribution and abundance with a set of spatiotemporal and oceanographic factors, using data collected by bottom trawl surveys and remote sensing in the central and southern Yellow Sea during 2000–2011. The fi nal model accounted for 28.21% and 41.03% of the variance in anchovy distribution and abundance, respectively. The results of a two-step GAM showed that hour, longitude, latitude, temperature gradient(TGR), and chlorophyll a(Chl- a) concentration best explained the anchovy distribution(presence/absence) and that a model including year, longitude, latitude, depth, sea surface temperature(SST), and TGR best described anchovy abundance(given presence). Longitude and latitude were the most important factors affecting both distribution and abundance, but the area of high abundance tended to be east and south of the area where anchovy were most likely to be present. Hour had a signifi cant effect on distribution, but year was more important for anchovy abundance, indicating that the anchovy catch ratio varied across the day but abundance had an apparent interannual variation. With respect to environmental factors, TGR and Chl- a concentration had effects on distribution, while depth, SST, and TGR affected abundance. Changes in SST between two successive years or between any year and the 2000–2011 mean were not associated with changes in anchovy distribution or abundance. This fi nding indicated that short- and long-term water temperature changes during 2000–2011 were not of suffi cient magnitude to give rise to variation in wintering anchovy distribution or abundance in the study area. The results of this study have important implications for fi sheries management. 展开更多
关键词 generalized additive model (GAM) oceanographic variables spatial distribution catch per unit effort (CPUE) Engraulisjaponicus
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Association between preoperative high sensitive troponin I levels and cardiovascular events after hip fracture surgery in the elderly 被引量:16
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作者 Bum Sung Kim Tae-Hoon Kim +5 位作者 Jeong-Hwan Oh Chang Hee Kwon Sung Hea Kim Hyun-Joong Kim Heung Kon Hwang Sang-Man Chung 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第3期215-221,共7页
Objective Cardiovascular complications contribute to postoperative morbidity and mortality in elderly hip fracture patients. Limited data are available regarding which preoperative risk factors predict cardiovascular ... Objective Cardiovascular complications contribute to postoperative morbidity and mortality in elderly hip fracture patients. Limited data are available regarding which preoperative risk factors predict cardiovascular course following hip fracture surgery (HFS). We used high sensitive troponin I (hs-TnI) assays and clinical parameters to identify preoperative risk factors associated with major adverse cardiac events (MACE) in elderly hip frac^u'e patients. Method From August 2014 to November 2016, 575 patients with hip fracture were enrolled in a retrospective, single-center registry. A total of 262 of these patients underwent HFS and hs-TnI assays. MACE was defined as postoperative all-cause deaths, heart failure (HF), new-onset atrial fibrillation (AF), myocardial infarction (MI) and cardiovascular re-hospitalization that occurred within 90 days postoperative. Results Of 262 HFS patients, MACE developed following HFS in 65 (24.8%). Patients with MACE were older and had higher rates of renal insufficiency, coronary artery disease, prior HF, low left ventricular ejection fraction and use of beta blockers; higher levels of hs-Tnl and N-terminal pro-brain natriuretic peptide (NT-proBNP) and higher revised cardiac risk index. A preoperative hs-TnI≥ 6.5 ng/L was associated with high risk of postoperative HF, new-onset AF and MACE. In multivariable analysis, pre-operative independent predictors for MACE were age 〉 80 years [adjusted hazard ratio (HR): 1.79, 95% confident interval (CI): 1.03-3.13, P = 0.04], left ventricular ejection fraction (LVEF) 〈 50% (adjusted HR: 3.17, 95% CI: 1.47-5.82, P 〈 0.01) and hs-TnI 〉 6.5 ng/L (adjusted HR: 3.75, 95% CI: 2.09~5.17, P 〈 0.01). Conclusion In elderly patients with hip fracture who undergo HFS, a preoperative assessment of hs-TnI may help the risk refinement of cardiovascular complications. 展开更多
关键词 Cardiovascular complication High sensitive troponin I Hip fracture surgery
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Current status of small yellow croaker resources in the southern Yellow Sea and the East China Sea 被引量:4
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作者 林龙山 刘尊雷 +2 位作者 姜亚洲 黄伟 高天翔 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第3期547-555,共9页
We used data from bottom trawl surveys to study the factors influencing the abundance of small yellow croaker, Larimichthys polyactis, in the southern Yellow Sea (SYS) and the East China Sea (ECS). The resource de... We used data from bottom trawl surveys to study the factors influencing the abundance of small yellow croaker, Larimichthys polyactis, in the southern Yellow Sea (SYS) and the East China Sea (ECS). The resource density index (RD1) was generally higher in summer and autumn than in spring and winter. RDIs were also significantly greater in the SYS than in the ECS in summer and autumn. The bottom water salinity and depth of spatial distribution of small yellow croaker was similar between the two areas in summer, but different in other seasons. Regression analysis suggested that environmental factors such as bottom water temperature, salinity, and depth influenced the RDIs in summer in these areas. Growth condition factor (GCF) in the two areas varied monthly and the croaker in the SYS grew more slowly than those in the ECS. This was likely due to the low bottom temperature of the Yellow Sea Cold Water Mass in summer and autumn or to higher human fishing pressure in the ECS. To ensure sustainable utilization of the croaker stocks in these regions, we recommend reducing the fishing intensity, increasing the cod-end mesh size, and improving the protection of juveniles. 展开更多
关键词 Larimichthys polyactis BIOLOGY ECOLOGY Akaike Information Criterion (AIC)
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