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41.
The aim of this study is to grade the intraoperative findings seen in carpal tunnel syndrome (CTS) based on severity, and compare it with clinical and electrodiagnostic severity.Thirty-one hands surgically treated for CTS were graded according to the severity of clinical signs, and electrodiagnostic tests. Oedema, vascularisation, and fibrosis were graded on a scale of 1–3. Pseudoneuroma or ‘hour-glass’ formation were graded as either 0 or 1. The hands were allocated by an observer into an assumptive severity group, from grade 1 to 3. Clinical severity and electrodiagnostic severity were statistically compared with each other, and with each intraoperative severity criteria.A high statistical correlation (p<0.01) was found between clinical severity and vascularisation, fibrosis, and the assumptive intraoperative severity. No correlation could be demonstrated between electrodiagnostic severity and the intraoperative criteria.Intraoperative grading should be regarded as a supportive measure to the clinical evaluation in order to obtain a sound base for surgical intervention and internal neurolysis.  相似文献   
42.
Lines in one orthographic and two perspective views   总被引:1,自引:0,他引:1  
We introduce a linear algorithm to recover the Euclidean motion between an orthographic and two perspective cameras from straight line correspondences filling the gap in the analysis of motion estimation from line correspondences for various projection models. The general relationship between lines in three views is described by the trifocal tensor. Euclidean structure from motion for three perspective views is a special case in which the relationship is defined by a collection of three matrices. Here, we describe the case of two calibrated perspective views and an orthographic view. Similar to the other cases, our linear algorithm requires 13 or more line correspondences to recover 27 coefficients of the trifocal tensor.  相似文献   
43.
    
The spontaneous combustion liability of coal can be determined by using different experimental techniques. These techniques are well-known in their application, but no certain test method has become a standard to prove the reliability of all of them. A general characterisation which included proximate and ultimate analyses, petrographic properties and spontaneous combustion tests(thermogravimetric analysis(TGA) and the Wits-Ehac tests) were conducted on fourteen coal and four coal-shale samples.The spontaneous combustion liability of these samples collected between coal seams(above and below)were predicted using the TGA and the Wits-Ehac tests. Six different heating rates(3, 6, 9, 15, 20 and 25 °C/min) were selected based on the deviation coefficient to obtain different derivative slopes and a liability index termed the TG_(spc) index. This study found that coal and coal-shale undergo spontaneous combustion between coal seams when exposed to oxygen in the air. Their intrinsic properties and proneness towards spontaneous combustion differ considerably from one seam to the other. The Wits-Ehac test results agreed with the TG_(spc) results to a certain extent and revealed the incidents of spontaneous combustion in the coal mines.  相似文献   
44.
    
The characterization of the physical and chemical properties of coal on a standard provides an understanding of its characteristics towards spontaneous combustion. The trend of linear relationships between coal recording standards (% air-dried (ad), % dry (db) and % dry ash free (daf) basis) of 30 selected coal samples from the Witbank coalfields and spontaneous combustion liability indices were evaluated. The spontaneous combustion liability indices of these samples were evaluated by crossing point temperature (XPT), Stage II Slope, FCC (Feng, Chakravorty, Cochrane) and the Wits-Ehac tests, while the coal properties were determined from the proximate and ultimate analyses. The results obtained from these coal properties were related to different liability indices to develop trends of linear relationships using regression analysis. The ad basis indicated higher correlation coefficients than the db and daf basis for the XPT and FCC index, while the daf showed higher correlation coefficients than the ad and db basis for the Wits-Ehac index. It was found that the trend of linear relationships of these coal properties differs from one liability index to the next. The XPTs showed a better trend followed by the Stage II Slope on the coal properties among the spontaneous combustion liability indices evaluated.  相似文献   
45.
Traditional integral snap-fit attachment design focuses almost exclusively on the individual locking features, such as cantilever hooks, bayonet-fingers, compressive hooks and others. The positioning and orientation of other significant features on parts, such as those that facilitate or enhance engagement and eliminate unwanted degrees of freedom left by locking features, i.e. locating features and enhancements, are not considered. This paper builds on relatively new methodologies and guidelines for arranging all attachment features on plastic parts comprising snap-fit assembly. Classification of features into categories of locking features, locating features and enhancements of these is used as the basis for discussion. A systematic approach to attachment design is presented.  相似文献   
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Multimedia Tools and Applications - In this era of technology, digital images turn out to be ubiquitous in a contemporary society and they can be generated and manipulated by a wide variety of...  相似文献   
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49.
Limited data are available on the serum levels of different sphingomyelin (CerPCho) and ceramide (CER) species in sickle‐cell disease (SCD). This study was aimed at identifying the levels of C16–C24 CerPCho and C16–C24 CER in serum obtained from SCD patients and controls. Circulating levels of neutral sphingomyelinase (N‐SMase) activity, ceramide‐1‐phosphate (C1P), and sphingosine‐1‐phosphate (S1P) were also determined. Blood was collected from 35 hemoglobin (Hb)A volunteers and 45 homozygous HbSS patients. Serum levels of C16–C24 CerPCho and C16–C24 CER were determined by an optimized multiple reaction monitoring (MRM) method using ultrafast liquid chromatography (UFLC) coupled with tandem mass spectrometry (MS/MS). Serum activity of N‐SMase was assayed by standard kit methods, and C1P and S1P levels were determined by enzyme‐linked immunosorbent assay. A significant decrease was observed in the serum levels of C18–C24 CerPCho in patients with SCD compared to controls. No significant difference was found in C16 CerPCho levels between the two groups. Very‐long‐chain C22–C24 CER were significantly decreased in SCD, while long‐chain C16–C20 CER levels showed no significant difference between SCD patients and controls. Significant positive correlation was found between the serum total cholesterol levels and C18–C24 CerPCho and C22–C24 CER in SCD patients. Patients with SCD had significantly elevated serum activity of N‐SMase as well as increased circulating levels of C1P and S1P compared to controls. The decrease in serum levels of C18–C24 CerPCho in patients with SCD was accompanied by decreased levels of C22–C24 CER. Future studies are needed to understand the role of decreased CerPCho and CER in the pathophysiology of SCD.  相似文献   
50.
Simple regression algorithms were developed to quantify spatio-temporal dynamics of minimum and maximum air temperatures (Tmin and Tmax, respectively) and soil temperature for a depth of 0-5 cm (Tsoil-5cm) across complex terrain in Turkey using Moderate Resolution Imaging Spectroradiometer (MODIS) data at a 500-m resolution. A total of 762 16-day MODIS composites (127 images × 6 bands) between 2000 and 2005 were averaged over a monthly basis to temporally match monthly Tmin, Tmax, and Tsoil-5cm from 83 meteorological stations. A total of 60 (28 temporally averaged plus 32 time series-based) linear regression models of Tmin, Tmax, and Tsoil-5cm were developed using best subsets procedure as a function of a combination of 12 explanatory variables: six MODIS bands of blue, red, near infrared (NIR), middle infrared (MIR), normalized difference vegetation index (NDVI), and enhanced vegetation index (EVI); four geographical variables of latitude, longitude, altitude, and distance to sea (DtS); and two temporal variables of month, and year. The best multiple linear regression models elucidated 65% (RMSE = 5.9 °C), 65% (RMSE = 5.1 °C), and 57% (RMSE = 6.9 °C) of variations in Tmin, Tmax, and Tsoil-5cm, respectively, under a wide range of Tmin (−34 to 25 °C), Tmax (0.2-47 °C) and Tsoil-5cm (−9 to 40 °C) observed at the 83 stations.  相似文献   
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