AIM:To investigate the diagnostic accuracy of the mean platelet volume and platelet distribution width in acute appendicitis.METHODS:This retrospective,case-controlled study compared 295 patients with acute appendicit...AIM:To investigate the diagnostic accuracy of the mean platelet volume and platelet distribution width in acute appendicitis.METHODS:This retrospective,case-controlled study compared 295 patients with acute appendicitis(Group?Ⅰ),100 patients with other intra-abdominal infections(GroupⅡ),and 100 healthy individuals(GroupⅢ)between January 2012 and January 2013.The age,gender,and white blood cell count,neutrophil percentage,mean platelet volume,and platelet distribution width values from blood samples were compared among the groups.Statistical analyses were performed using SPSS for Windows 21.0 software.In addition,the sensitivity,specificity,positive and negative predictive values and likelihood ratios,and diagnostic accuracy were calculated.RESULTS:The mean ages of patients were 29.9±12.0years for Group?Ⅰ,31.5±14.0 years for GroupⅡ,and30.4±13.0 years for GroupⅢ.Demographic features such as age and gender were not significantly different among the groups.White blood cell count,neutrophil percentage and platelet distribution width were significantly higher in Group?Ⅰ?compared to groupsⅡandⅢ(P<0.05).Diagnostically,the sensitivity,specificity and diagnostic accuracy were 73.1%,94.0%,and 78%for white blood cell count,70.0%,96.0%,and 76.0%for neutrophil percentage,29.5%,49.0%,and 34.0%for mean platelet volume,and 97.1%,93.0%,and 96.0%for platelet distribution width,respectively.The highest diagnostic accuracy detected was for platelet distribution width between Group?Ⅰ?and GroupⅢ(P<0.01).CONCLUSION:Platelet distribution width analysis can be used for diagnosis of acute appendicitis without requiring additional tests,thus reducing the cost and loss of time.展开更多
This study proposes an equivalent-elevation method to evaluate the integrated effects of latitude and elevation on regional and local-scale permafrost distribution in the Qinghai-Tibet Plateau,and to model the general...This study proposes an equivalent-elevation method to evaluate the integrated effects of latitude and elevation on regional and local-scale permafrost distribution in the Qinghai-Tibet Plateau,and to model the general permafrost-distribution patterns in regional and local-scale area.It is found that the Gaussian curve―an empirical model describing the relation between variations of altitudinal permafrost lower limit (PLL) and latitude in the Northern Hemisphere―could be applied in regional-and local-scale areas in the Qinghai-Tibet Plateau in a latitude-sensitive interval of 30°-50°N.The curve was then used to evaluate the latitudinal effect on permafrost distribution through transforming the latitudinal effect into a kind of altitudinal difference of PLL.This study then calculated the local equivalent-elevation value by overlaying the altitudinal difference of PLL onto real elevation at a certain location.The equivalent-elevation method was verified in an experimental subwatershed of the Qinghai-Tibet Plateau.However,feasibility of the method should be further tested in order to extend for future studies.The use of equivalent-elevation values can build a platform for comparing the regional general permafrost distribution in the plateau,and for basing further evaluations of local factors' effects on regional permafrost distribution.展开更多
Digital factory technology is an advanced manufacturing technology served as to establish a bridge between the process of product development and manufacturing.In terms of application for digital factory technology in...Digital factory technology is an advanced manufacturing technology served as to establish a bridge between the process of product development and manufacturing.In terms of application for digital factory technology in machining,especially in machining of a complicated part such as a cylinder body part,a concept of digital process planning and its framework are proposed.Its components including machining domain knowledge model,machining knowledge base,machining resource base and process planning system are studied.A machining knowledge model in tree form and an object-driven knowledge reasoning mechanism are used for machining knowledge base.The process planning system is a user interface that leads a planner to finish the planning process.A case about a cylinder head part is given to demonstrate how the platform works.The framework of digital process planning is the foundation of some intelligent CAPP systems and helps to production line planning.展开更多
文摘AIM:To investigate the diagnostic accuracy of the mean platelet volume and platelet distribution width in acute appendicitis.METHODS:This retrospective,case-controlled study compared 295 patients with acute appendicitis(Group?Ⅰ),100 patients with other intra-abdominal infections(GroupⅡ),and 100 healthy individuals(GroupⅢ)between January 2012 and January 2013.The age,gender,and white blood cell count,neutrophil percentage,mean platelet volume,and platelet distribution width values from blood samples were compared among the groups.Statistical analyses were performed using SPSS for Windows 21.0 software.In addition,the sensitivity,specificity,positive and negative predictive values and likelihood ratios,and diagnostic accuracy were calculated.RESULTS:The mean ages of patients were 29.9±12.0years for Group?Ⅰ,31.5±14.0 years for GroupⅡ,and30.4±13.0 years for GroupⅢ.Demographic features such as age and gender were not significantly different among the groups.White blood cell count,neutrophil percentage and platelet distribution width were significantly higher in Group?Ⅰ?compared to groupsⅡandⅢ(P<0.05).Diagnostically,the sensitivity,specificity and diagnostic accuracy were 73.1%,94.0%,and 78%for white blood cell count,70.0%,96.0%,and 76.0%for neutrophil percentage,29.5%,49.0%,and 34.0%for mean platelet volume,and 97.1%,93.0%,and 96.0%for platelet distribution width,respectively.The highest diagnostic accuracy detected was for platelet distribution width between Group?Ⅰ?and GroupⅢ(P<0.01).CONCLUSION:Platelet distribution width analysis can be used for diagnosis of acute appendicitis without requiring additional tests,thus reducing the cost and loss of time.
基金Under the auspices of Major State Basic Research Development Program of China(No.2010CB951402)National Natural Science Foundation of China(No.41101067)+1 种基金Foundation for Excellent Youth Scholars of Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences(No.Y184A91001)Research Program of State Key Laboratory of Frozen Soil Engineering of Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences(No.SKLFSE-ZQ-10)
文摘This study proposes an equivalent-elevation method to evaluate the integrated effects of latitude and elevation on regional and local-scale permafrost distribution in the Qinghai-Tibet Plateau,and to model the general permafrost-distribution patterns in regional and local-scale area.It is found that the Gaussian curve―an empirical model describing the relation between variations of altitudinal permafrost lower limit (PLL) and latitude in the Northern Hemisphere―could be applied in regional-and local-scale areas in the Qinghai-Tibet Plateau in a latitude-sensitive interval of 30°-50°N.The curve was then used to evaluate the latitudinal effect on permafrost distribution through transforming the latitudinal effect into a kind of altitudinal difference of PLL.This study then calculated the local equivalent-elevation value by overlaying the altitudinal difference of PLL onto real elevation at a certain location.The equivalent-elevation method was verified in an experimental subwatershed of the Qinghai-Tibet Plateau.However,feasibility of the method should be further tested in order to extend for future studies.The use of equivalent-elevation values can build a platform for comparing the regional general permafrost distribution in the plateau,and for basing further evaluations of local factors' effects on regional permafrost distribution.
文摘Digital factory technology is an advanced manufacturing technology served as to establish a bridge between the process of product development and manufacturing.In terms of application for digital factory technology in machining,especially in machining of a complicated part such as a cylinder body part,a concept of digital process planning and its framework are proposed.Its components including machining domain knowledge model,machining knowledge base,machining resource base and process planning system are studied.A machining knowledge model in tree form and an object-driven knowledge reasoning mechanism are used for machining knowledge base.The process planning system is a user interface that leads a planner to finish the planning process.A case about a cylinder head part is given to demonstrate how the platform works.The framework of digital process planning is the foundation of some intelligent CAPP systems and helps to production line planning.
