The ability of EUS to diagnose small pancreatic cancer is well known. In this study, we present our experience with EUS in the local staging of 29 patients with pancreatic carcinoma who underwent surgery. EUS was 79, 83 and 79% accurate in determining anterior (including gastric), duodenal and retroperitoneal (vascular) invasion by the tumor. Ultrasonography (48, 39 and 55%, respectively) and CT (38, 33 and 41%, respectively) were less reliable. EUS was equal to angiography in diagnosing vascular involvement. EUS was more effective in detecting splenoportal infiltration (sensitivity 88%, specificity 78%) than arterial involvement (accuracy 50%). EUS was also less reliable in determining the N stage (66%) and in stage grouping (72%). Although EUS is superior to ultrasonography and CT in the local staging of pancreatic carcinoma, further studies must show whether improved staging criteria will lead to better results.
The structure and properties of Murata vortex spun yarns are investigated and compared with ring and open-end rotor spun yarns. Cotton yarns are spun from the same lot of Australian raw cotton fibers using the Murata vortex, ring, and open-end rotor spinning methods. Yarn structures are observed with an optical microscope equipped with a digital camera. Based on the digitized photographs, fiber arrangements are classified as wild, wrapper-wild, wrapper, belly-band. and core. Yarn diameter, yarn helix angle, wrapper fiber pitch, wrapper fiber crest, wrapper fiber length for a one-turn twist, and wrapper fiber helix angle to the yarn axis are examined, and yarn parameters such as tenacity, evenness, and hairiness are evaluated. The mechanical properties of dry relaxed yarns are measured with Kawabata Evaluation System instruments. Attempts are made to relate yarn structure differences to differences in the yarn formation mechanism for the three spinning meth ods. The differences in measured yarn properties such as evenness, hairiness, bulkiness. tenacity, compression properties, and bending properties can be explained by the observed differences in the yarn structure.
The effects of laundering and laundering temperatures on surface properties and dimensional stability are investigated for plain flat knit silk, cotton, and polyester fabrics with varying cover factors. The fabrics are subjected to relaxation processes and an extended series of wash and tumble-dry cycles in laundering baths of various tempera tures. Dimensions, surface friction, and roughness of the fabrics are measured in every process. Changes in dimensional stability and surface properties with relaxation processes and laundering temperatures are clarified. Relations between frictional motion and struc tural parameters are also discussed. The results reveal that the dimensional stability of silk is sensitive to a particular temperature. The highest shrinkage is recorded with slackly knitted cotton at the highest temperature. There is a considerable effect of wet relaxation on dimensional stability as well as surface properties. Silk's coefficient of friction is the highest, and the lowest surface friction for cotton occurs at the highest temperature. Slackly knitted fabrics also show higher friction than tightly knitted fabrics. The coeffi cient of friction has a tendency to decrease with increasing tightness, while the surface roughness shows an opposite tendency. There is a good correlation between stick-slip motion and ribs on the fabrics.
Deformation by laundering is investigated for single jersey and 1 × 1 rib flat knit silk and cotton fabrics with yams of varying linear densities and fabric tightness. The fabrics are subjected to relaxation processes and an extended series of wash and tumble- dry cycles. Changes in dimensions are measured in every process and cycle. Statistical analyses of the experimental data reveal the effect of yam type as well as linear density and tightness factor on the linear and area shrinkage behavior of silk as compared to cotton. Cotton shrinks more than silk, and silk rib knits stretch excessively in width. Silk attains full relaxation after one laundering cycle. Microscopic views reveal the appearance of ball-like formations along silk fibers after repeated laundering. It is possible to predict fabric dimensional changes with wet relaxation as well as with laundering, especially in silk.
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