5,075 research outputs found
Solution-processed germanium nanowire-positioned Schottky solar cells
Germanium nanowire (GeNW)-positioned Schottky solar cell was fabricated by a solution process. A GeNW-containing solution was spread out onto asymmetric metal electrodes to produce a rectifying current flow. Under one-sun illumination, the GeNW-positioned Schottky solar cell yields an open-circuit voltage of 177 mV and a short-circuit current of 19.2 nA. Schottky and ohmic contacts between a single GeNW and different metal electrodes were systematically investigated. This solution process may provide a route to the cost-effective nanostructure solar architecture
The Morphologic Assessment of Rectal Neuroendocrine Tumors
AbstractBackground and aimsThe histopathologic features of rectal neuroendocrine tumors (NETs), including size, lymphovascular invasion, invasion of proper muscle, and mitotic rate, have a limited role to play in determining a treatment plan preoperatively. We aimed to investigate the morphologic parameters associated with metastasis, and to evaluate their predictive value.MethodsBetween January 2000 and May 2011, the medical records and endoscopic findings of 468 patients presenting with rectal NETs at the Samsung Medical Center were analyzed retrospectively. All tumors were classified according to size and endoscopic features such as color, shape, contour, and surface change.ResultsTwenty-one of the 468 patients (4.5%) with rectal NETs had lymph node (LN) metastasis and 11 patients (2.4%) had distant metastasis. Risk factors for metastasis included tumor size (≥10mm in diameter), hyperemic change, polypoid lesions, irregular contours, and surface ulceration (p=0.000). Independent risk factors that were predictive of metastasis on multivariate analysis included tumor size (≥10mm in diameter), hyperemic change, and surface ulceration. As the number of independent risk factors for metastasis increased, the risk of metastasis rose.ConclusionsEndoscopic features such as hyperemic change, polypoid lesions, irregular contours, and surface ulcers with tumor size ≥10mm in diameter are associated with metastasis in rectal NETs. In particular, atypical endoscopic features including hyperemic change, and surface ulcer with tumor size ≥10mm in diameter may help to predict the risk of metastasis of rectal NETs
HOW CAN WE TEACH STUDENT TO ESTIMATE VERTICAL JUMP HEIGHTS USING GROUND REACTION FORCE DATA
The purpose of this study was to estimate vertical jump heights using ground reaction force (GRF) data and to suggest one practical example of biomechanical theory application to a real human motion. Vertical jump heights of impulse and flight time method were statistically smaller than three-dimensional video method. The causes of height differences seemed mainly from the fact that impulse was used to move jumper into the horizontal direction as well as into the vertical direction. Other important factors for accurate height calculation are jumper's mass and threshold value of GRF data collection. Vertical jump height calculation with GRF data showed an example of practical application of biomechanical theory to human motion and demonstrated a way of GRF equipment use for effective biomechanical theory education
Ultrasound-guided central venous catheter insertion in pediatric patients
In pediatric patients, central venous catheterization (CVC) is necessary for administration of fluids, drugs, high concentration electrolytes, vasopressors or inotropic drugs, transfusion, intravenous nutrition, and dialysis. Using an anatomical landmark for the CVC insertion may have a low success rate in children due to the positional variation between the deep vein and the landmarks, the small size of body and blood vessels, low insertion frequency, and operator skill. In order to improve the success rate, ultrasound guided CVC insertion is recommended in critically ill children. It is also expected to reduce mechanical complications, which are more common with subclavian CVC insertion. However, the association between the insertion site and the infection or thrombosis is unclear. Since thrombosis is relatively common, further studies are needed on the association between the incidence rate and insertion sites
A Preliminary Report of Crosslinguistic Evidence on Efficacy of Semantic-Complexity Based Naming Treatment in Korean Aphasics
The current study investigated the efficacy of semantic-complexity based naming treatment in Korean participants with aphasia. Results suggested that both participants showed small to medium effect sizes in the trained items. However, generalization effects were greater in the participant who received treatment on the atypical items first, than the participant who was initiated on the typical items. These results are consistent with the previous findings in English-speaking aphasic participants (Kiran & Thompson, 2003; Kiran, 2008). Preliminary findings of two Korean participants with aphasia added crosslinguistic evidence on efficacy of the semantic complexity based naming treatment
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