Plastic deformation behavior of Cu thin films during fatigue testing

AbstractPlastic deformation behavior of electrodeposited copper films with thickness of 12 μm was investigated by using a testing system employed an electro-dynamic actuator. During the fatigue tests, cyclic plastic strain and ratcheting strain were measured continuously with high precision by using the capacitance extensometer. Since the displacement gage is stable and its response is so fast, the deformation can be measured in real time during fatigue tests as well as tensile tests. The cyclic plastic strain range and monotonic plastic strain increase with loading cycles and they are similar to the conventional creep curve. The monotonic plastic strain at fracture is nearly constant, irrespective of mean stress, indicating that the monotonic plastic strain can be used as an indicator of damage. Based on these results, a prediction method for the monotonic plastic strain is proposed. It could be found from the prediction results that the monotonic plastic strain is well predicted

Computed tomography–assessed presarcopenia and clinical outcomes after laparoscopic surgery for rectal cancer

Purpose Previous studies have reported that presarcopenia negatively affects rectal cancer treatment. However, most studies have analyzed patients including majority of open surgery, and the association between presarcopenia and clinical outcomes after laparoscopic rectal cancer surgery remains unclear. This study aimed to evaluate the impact of presarcopenia on the clinical and oncological outcomes after laparoscopic rectal cancer surgery. Methods Three hundred and one patients undergoing laparoscopic rectal cancer surgery between December 2009 and May 2016 were enrolled. Body composition was assessed using computed tomography by measuring the muscle and fat areas at the third lumbar (L3) vertebra. The L3 skeletal muscle area was used to calculate the skeletal muscle index and evaluate presarcopenia. Results Presarcopenia was more common in older (≥70 years, P=0.008) or female patients (P=0.045). Patients with presarcopenia had decreased skeletal muscle area (P<0.001), lower hemoglobin level (P=0.034), longer time to first flatus (P<0.001), and more frequent surgical site infection (P=0.001). However, survival rates were not significantly different between those with and without presarcopenia. Conclusion Computed tomography-assessed presarcopenia was associated with delayed functional recovery and increased surgical site infection, although it was not revealed as a prognostic factor for oncological outcomes

Effects of creatine and β-guanidinopropionic acid and alterations in creatine transporter and creatine kinases expression in acute seizure and chronic epilepsy models

<p>Abstract</p> <p>Background</p> <p>In order to confirm the roles of creatine (Cr) in epilepsy, we investigated the anti-convulsive effects of Cr, creatine transporter (CRT) and creatine kinases (CKs) against chemical-induced acute seizure activity and chronic epileptic seizure activity.</p> <p>Results</p> <p>Two hr after pilocarpine (PILO)-seizure induction, ubiquitous mitochondrial CK (uMtCK) immunoreactivity was unaltered as compared to control level. However, brain-type cytoplasm CK (BCK) immunoreactivity was decreased to 70% of control level. CRT immunoreactivity was decreased to 60% of control level. Following Cr or Tat-CK treatment, uMtCK or CRT immunoreactivity was unaffected, while BCK immunoreactivity in Cr treated group was increased to 3.6-fold of control levels. β-Guanidinopropionic acid (GPA, a competitive CRT inhibitor) reduced BCK and CRT expression. In addition, Cr and tat-BCK treatment delayed the beginning of seizure activity after PILO injection. However, GPA treatment induced spontaneous seizure activity without PILO treatment. In chronic epilepsy rats, both uMtCK and CRT immunoreactivities were reduced in the hippocampus. In contrast, BCK immunoreactivity was similar to that observed in control animals. Cr-, GPA and tat-BCK treatment could not change EEG.</p> <p>Conclusion</p> <p>Cr/CK circuit may play an important role in sustaining or exacerbating acute seizure activity, but not chronic epileptic discharge.</p

Hydrauric Analysis On Water Stage Change Along The Submerged Weir And Tides Effect In Han River

Sinkok submerged weir in Han river, Seoul Korea was built in early 1980’s for the purpose of water level maintenance and protection from sea water intrusion from the estuary. Its length is almost 1 km and 2.4 meter height which has two composite structures of rigid and movable weir. Huge wetland developed as the results of weir construction just down to the weir. However, recently social conflicts for the weir removal occurred for the river rehabilitation and aqua-eco system recover. This study focused on hydraulic analysis, especially water level changes in terms of with and without submerged weir along the tides where the height has 9 meters difference between ebb and high tide. HEC-RAS for the 1-D simulation and SMS for 2-D analysis were used covering 25 km river length and tributaries. Tides time series records and discharge records from upstream dam of 1-year were and 2 submerged weirs as well as 25 bridges were considered in boundaries. Hydraulic data in the 4 gauging stations were collected for the model calibration. Water level changes were reviewed along 4 cases – with/without weir and flood/dry season - The results showed that more than 3 meter difference of water surface fluctuation along up and downstream including wetland as tide changes in a day. The wetland dimension and water quality were also affected along the water level. The contraction of wetland area might cause the changes of aqua habitat to plants and animals. These results make it difficult to make a decision of removal of the submerged weir. A comprehensive analysis of not only hydraulic but also water quality and environmental effect should be considered. Achknowledgement : This research was supported by a grant (12-TI-C01) from Advanced Water Management Research Program funded by Ministry of Land, Infrastructure and Transport of Korean governmen