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Correlation of Inferior Vena Cava Respiratory Variability Index with Central Venous Pressure and Hemodynamic Parameters in Ventilated Pigs with Septic Shock 被引量:3
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作者 LIU Xiao Lei TAO Yong Kang +5 位作者 YAN Sheng Tao QI Zhi Wei LU Hai Tao WANG Hai Feng GU Cheng Dong ZHANG Guo Qiang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第6期500-503,共4页
Septic shock is a common critical condition, for which effective early fluid resuscitation is the therapeutic focus. According to the 2008 international guidelines for management of severe sepsis and septic shock, res... Septic shock is a common critical condition, for which effective early fluid resuscitation is the therapeutic focus. According to the 2008 international guidelines for management of severe sepsis and septic shock, resuscitation should achieve a central venous pressure (CVP) of 8-12 mmHg within the first 6 h. However, it is still uncertain about the sensitivity and specificity of CVP in reflecting the cardiac preload. Ultrasonography is a simple, rapid, non-invasive, and repeatable method for the measurement of sensitivity and specificity of CVP and has thus gradually attracted the increasing attention of physicians. It was reported that ultrasonography can show the inferior vena cava diameter, respiratory variability index, and blood volume in patients with sepsis or heart failure. 展开更多
关键词 CVP SVV Correlation of Inferior Vena Cava Respiratory Variability index with Central Venous Pressure and Hemodynamic parameters in Ventilated Pigs with Septic Shock
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Structure Parameters and Physiological Indices Research of High-quality and High-yield Apple Orchards 被引量:1
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作者 薛晓敏 王翠玲 +2 位作者 王金政 孟海凤 聂佩显 《Agricultural Science & Technology》 CAS 2014年第11期1953-1956,1959,共5页
In order to research environment parameters and physiological indices of high-quality and high-yield apple trees, two orchards with young and mature apples trees were investigated to explore structural parameter of ap... In order to research environment parameters and physiological indices of high-quality and high-yield apple trees, two orchards with young and mature apples trees were investigated to explore structural parameter of apple tree and community, and some physiological indices in fields and by room measurements. The results showed that tree height of high-quality orchard was in the range of 260 to 290 cm, branch angle in 70°-75°, and orchard coverage rate in 75%-94%, and the connec-tion rates between rows and trees were lower. Furthermore, the total branches of mature orchard reached 1.04 ×106 per hm2, while the young orchard was 8.79 ×105 per hm2; the leaves were thick and chlorophyl content was high, with SPAD value at 58.22. Additional y, the photosynthesis of the orchard was strong, and net photo-synthetic rate was 17.48-21.8 μmolCO2/(m2·s). The proportions of lateral shoot of bearing part were 81% and 75% respectively. 展开更多
关键词 High-quality and high-yield Apple orchard Structure parameters Physio-logical index
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Important population viability analysis parameters for giant pandas(Aliuropoda melanoleuca) 被引量:3
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作者 Minghao GONG Yanling SONG +1 位作者 Zhisong YANG Chen LIN 《Zoological Research》 CAS CSCD 北大核心 2012年第3期I0018-I0024,共7页
Population viability analysis(PVA) is a tool to evaluate the risk of extinction for endangered species and aid conservation decision-making.The quality of PVA output is dependent on parameters related to population dy... Population viability analysis(PVA) is a tool to evaluate the risk of extinction for endangered species and aid conservation decision-making.The quality of PVA output is dependent on parameters related to population dynamics and life-history;however,it has been difficult to collect this information for the giant panda(Aliuropoda melanoleuca),a rare and endangered mammal native to China,confined to some 30 fragmented habitat patches.Since giant pandas are long-lived,mature late,have lower reproductive rates,and show little sexual dimorphism,obtaining data to perform adequate PVA has been difficult.Here,we develop a parameter sensitivity index by modeling the dynamics of six giant panda populations in the Minshan Mountains,in order to determine the parameters most influential to giant panda populations.Our data shows that the giant panda populations are most sensitive to changes in four female parameters:initial breeding age,reproductive rate,mortality rate between age 0 and 1,and mortality rate of adults.The parameter sensitivity index strongly correlated with initial population size,as smaller populations were more sensitive to changes in these four variables.This model suggests that demographic parameters of females have more influence on the results of PVA,indicating that females may play a more important role in giant panda population dynamics than males.Consequently,reintroduction of female individuals to a small giant panda population should be a high priority for conservation efforts.Our findings form a technical basis for the coming program of giant panda reintroduction,and inform which parameters are crucial to successfully and feasibly monitoring wild giant panda populations. 展开更多
关键词 Giant panda PVA Population parameter Parameter sensitivity index
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Development of a drill energy utilization index for aiding selection of drill machines in surface mines 被引量:1
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作者 Kumar Suraj Rahul Talreja Murthy V.M.S.R. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第3期393-399,共7页
Drill machines used in surface mines, particularly in coal, is characterized by a very poor utilization (around 40%) and low availability (around 60%). The main purpose of this study is to develop a drill selec- t... Drill machines used in surface mines, particularly in coal, is characterized by a very poor utilization (around 40%) and low availability (around 60%). The main purpose of this study is to develop a drill selec- tion methodology and simultaneously a performance evaluation technique based on drill cuttings produced and drilling rate achieved. In all 28 blast drilled through were investigated. The drilling was accomplished by 5 different drill machines of Ingersoll-Rand and Revathi working in coal mines of Sonepur Bazari (SECL) and Block-II (BCCL). The drills are Rotary and Rotary Percussive type using tri- cone rock roller bits. Drill cuttings were collected and sieve analysis was done in the laboratory. Using Rosin Ramler Diagram, coarseness index (CI), mean chip size (d), specific-st trace area (SSA) and charac- teristic particle size distribution curves for all the holes drilled were plotted. The predictor equation for drill penetration rate established through multiple regressions was found to have a very good correlation with an index of determination of 0.85. A comparative analysis of particle size distribution curves was used to evaluate the drill efficiency. The suggested approach utilises the area under the curve, after the point of trend reversal and brittleness ratio of the respective bench to arrive at drill energy utilization index (DEUI), for mapping of drill machine to bench, The developed DEU1 can aid in selecting or mapping a right machine to right bench for achieving higher penetration rate and utilizations. 展开更多
关键词 Drill cutting parameter Coarseness index Mean chip size Specific surface area Particle size distribution curves Drill energy ptilization index
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Important population viability analysis parameters for giant pandas(Aliuropoda melanoleuca)
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作者 Minghao GONG Yanling SONG +1 位作者 Zhisong YANG Chen LIN 《Zoological Research》 SCIE CAS CSCD 北大核心 2012年第S01期18-24,共7页
Population viability analysis(PVA)is a tool to evaluate the risk of extinction for endangered species and aid conservation decision-making.The quality of PVA output is dependent on parameters related to population dyn... Population viability analysis(PVA)is a tool to evaluate the risk of extinction for endangered species and aid conservation decision-making.The quality of PVA output is dependent on parameters related to population dynamics and life-history;however,it has been difficult to collect this information for the giant panda(Aliuropoda melanoleuca),a rare and endangered mammal native to China,confined to some 30 fragmented habitat patches.Since giant pandas are long-lived,mature late,have lower reproductive rates,and show little sexual dimorphism,obtaining data to perform adequate PVA has been difficult.Here,we develop a parameter sensitivity index by modeling the dynamics of six giant panda populations in the Minshan Mountains,in order to determine the parameters most influential to giant panda populations.Our data shows that the giant panda populations are most sensitive to changes in four female parameters:initial breeding age,reproductive rate,mortality rate between age 0 and 1,and mortality rate of adults.The parameter sensitivity index strongly correlated with initial population size,as smaller populations were more sensitive to changes in these four variables.This model suggests that demographic parameters of females have more influence on the results of PVA,indicating that females may play a more important role in giant panda population dynamics than males.Consequently,reintroduction of female individuals to a small giant panda population should be a high priority for conservation efforts.Our findings form a technical basis for the coming program of giant panda reintroduction,and inform which parameters are crucial to successfully and feasibly monitoring wild giant panda populations. 展开更多
关键词 Giant panda PVA Population parameter Parameter sensitivity index
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Parameter analysis of a photonic crystal fiber with raised-core index profile based on effective index method 被引量:7
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作者 Faramarz E.Seraji Mahnaz Rashidi Vajieh Khasheie 《Chinese Optics Letters》 SCIE EI CAS CSCD 2006年第8期442-445,共4页
Photonic crystal fibers (PCFs) with a stepped raised-core profile and one layer equally spaced holes in the cladding are analyzed. Using effective index method and considering a raised step refractive index differen... Photonic crystal fibers (PCFs) with a stepped raised-core profile and one layer equally spaced holes in the cladding are analyzed. Using effective index method and considering a raised step refractive index difference between the index of the core and the effective index of the cladding, we improve the characteristic parameters such as numerical aperture and V-parameter, and reduce its bending loss to about one tenth of a conventional PCF. Implementing such a structure in PCFs may be one step forward to achieve low loss PCFs for communication applications. 展开更多
关键词 PCF Parameter analysis of a photonic crystal fiber with raised-core index profile based on effective index method
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Testing for the parametric parts in a single-index varying-coefficient model
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作者 HUANG ZhenSheng ZHANG RiQuan 《Science China Mathematics》 SCIE 2012年第5期1017-1028,共12页
Single-index varying-coefficient models (SIVCMs) are very useful in multivariate nonparametric regression.However,there has less attention focused on inferences of the SIVCMs.Using the local linear method,we propose e... Single-index varying-coefficient models (SIVCMs) are very useful in multivariate nonparametric regression.However,there has less attention focused on inferences of the SIVCMs.Using the local linear method,we propose estimates of the unknowns in the SIVCMs.In this article,our main purpose is to examine whether the generalized likelihood ratio (GLR) tests are applicable to the testing problem for the index parameter in the SIVCMs.Under the null hypothesis our proposed GLR statistic follows the chi-squared distribution asymptotically with scale constant and degree of freedom independent of the nuisance parameters or functions,which is called as Wilks' phenomenon (see Fan et al.,2001).A simulation study is conducted to illustrate the proposed methodology. 展开更多
关键词 generalized likelihood ratio index parameter local smoothing method single-index models Wilks' type of phenomenon
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A New Parameter as an Indicator of the Degree of Deformation of Coals 被引量:1
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作者 Mingming Wei Yiwen Ju +4 位作者 Quanlin Hou Guochang Wang Liye Yu Wenjing Zhang Xiaoshi Li 《Journal of Earth Science》 SCIE CAS CSCD 2017年第2期358-366,共9页
The deformation of coal is effected by thermal effect, pressures and tectonic stress, and the tectonic stress is the principal influence factor. However, the proposition of a useful quantitative index that responds to... The deformation of coal is effected by thermal effect, pressures and tectonic stress, and the tectonic stress is the principal influence factor. However, the proposition of a useful quantitative index that responds to the degree of deformation of coals quantitatively or semi-quantitatively has been a long-debated issue. The vitrinite reflectance ellipsoid, that is, the reflectance indication surface(RIS) ellipsoid is considered to be a strain ellipsoid that reflects the sum of the strain increment caused by stress in the process of coalification. It has been used to describe the degree of deformation of the coal, but the effect of the anisotropy on the RIS ellipsoid has not yet been considered with regards to non-structural factors. In this paper, Wei's parameter(ε) is proposed to express the deformation degree of the strain ellipsoid based on considering the combined influence of thermal effect, pressure and tectonic stress. The equation is as follows: ε=√[(ε_1-ε_0)~2+(ε_2-ε_0)~2+(ε_3-ε_0)~2]/3, where ε_1=lnR_(max), ε_2=lnR_(int), ε_3=lnR_(min), and ε_0=(ε_1+ε_2+ε_3)/3. Wei's parameter represents the distance from the surface to the spindle of the RIS logarithm ellipsoid; thus, the degree of deformation of the strain ellipsoid is indicated quantitatively. The formula itself, meanwhile, represents the absolute value of the degree of relative deformation and is consequently suitable for any type of deformation of the strain ellipsoid. Wei's parameter makes it possible to compare degrees of deformation among different deformation types of the strain ellipsoid. This equation has been tested in four types of coal: highly metamorphic but weakly deformed coal of the southern Qinshui Basin, highly metamorphic and strongly deformed coal from the Tianhushan coal mining area of Fujian, and medium metamorphic and weakly or strongly deformed coal from the Huaibei Coalfield. The results of Wei's parameters are consistent with the actual deformation degrees of the coal reservoirs determined by other methods, which supports the effectiveness of this method. In addition, Wei's parameter is an important complement to the indicators of the degrees of deformation of coals, which possess certain theoretical significance and practical values. 展开更多
关键词 Wei's parameter(ε) deformation degree of coals quantitative index vitrinite reflectance ellipsoid
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