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Steel structures in social infrastructures often undergo corrosion and the thickness of these steel plates decreases. Then, the strength of steel structures decreases according to the residual plate thickness. Applications of a steel plate attaching method and a fiber reinforced polymer/plastic (FRP) bonding method are effective for repair and strengthening for these steel structures. In this study, UV-curable glass fiber reinforced polyester resin (UV-GFRPR) sheet was focused instead of FRPs. The aims of this study are to confirm repair and strengthening effects of the UV-GFRPR sheet bonded on both sides of steel plate. The UV-GFRPR sheet consists of a polyester resin and chopped glass fibers and is hardened by radiation of UV source for a certain time. The tensile behavior and strength of steel plate bonded with UV-GFRPR sheets were assessed under axial tensile load. After that, the tensile behavior and strength of specimens were numerically estimated from each stress-strain curve of UV-GFRPR and steel modeled by using Menegotto-Pinto model. Furthermore, nonlinear finite element analysis (FEA) taking into account of the properties of bond layers was carried out to compare the numerical results. From the test results, the yield and ultimate strengths of specimens increased linearly according to the number of laminated layers of UV-GFRPR. Both results of the numerical calculation and the FEA agreed well with the test results. It is concluded that the numerical calculation without the contribution of bond layers can estimate the tensile behavior and strength of steel plate bonded with UV-GFRPR on both sides. [ABSTRACT FROM AUTHOR]

Abstract  In Central Kalimantan, Indonesia, the water of lakes and rivers showed high dissolved organic carbon (DOC) concentration, 5-50mgC/l. There was a clear relationship between DOC concentration and pH. DOC also contributed to low water transparency in the studied lakes. Water colors measured by spectrophotometer showed a strong relationship with DOC concentration, indicating high applicability of water color measurement for estimation of DOC. The development of a simple but quick estimation of DOC will contribute to understanding the seasonal dynamics of DOC, which might regulate both abiotic and biotic conditions in aquatic ecosystems in this area. [ABSTRACT FROM AUTHOR]

Pacemaker. QT interval (QTI) may change when cardiac junction is improved by optimizing the AV delay. QTI is used as the sensor for rate responsive pacemakers. Evoked (e)QTI is measured as the time duration from the ventricular pace-pulse to the T sense point, which is the steepest point of the intracardiac T wave. The relationship between AV delay and eQTI and cardiac function was studied in 13 patients (74.2 ± 9.3 [SD] years old) with an implanted QT-driven DDDR pacemaker. A special pacemaker software module was downloaded into the pacemaker memory for eQTI data logging. AV delay was set at 100, 120, 150, 180, 210, and 240 ms. Cardiac output (CO) was measured by' continuous Doppler echocardiography eQTI was 343.3 ± 22.5, and 343.4 ± 23.2 ms (P < 0.01. repeated ANOVA) and CO was 4.2 ± 0.8, 4.6 ± 0.8, and 4.2 ± 0.8 L/min (P < 0.0001, repeated ANOVA) when AV delay was set at the AV delay shortened by one step (AV[-]) and prolonged by one step (AV[+]) from the AV delay at which QT interval was maximum (AV[max]) in seven patients, in whom the peak AV delay at which the eQTI was maximal could be identified. eQTI decreased from 345.1 ± 20.9 to 339.4 ± 21.1 ms (P < 0.0001) and CO decreased from 4.4 ± 1.4 to 4.1 ± 1.3 L/min (P <0.005) when AV delay was prolonged from AV(max) to AV(+) in all patients. eQTI decreased from 345.1 ± 22.5 to 343.3 ± 22.4 ms (P < 0.0005) and CO decreased from 4.6 ± 0.8 to 4.2 ± 0.8 L/min (P < 0.05) when AV delay was shortened from AV(max) to AV(-) in seven patients. Thus, CO was maximal when AV delay was set at the AV delay at which eQTI was maximal. In conclusion, the optimal AV delay can be predicted from the eQTI sensed by an implanted pacemaker. and automatic setting of the optimal A V delay can be achieved by the QT sensor of an implanted pacemaker. [ABSTRACT FROM AUTHOR]

The article presents several abstracts concerning metabolic and hemodynamic variables related to pacing. One of the abstracts provides that implanted multi-programmable pacemakers were tested according to three treadmill protocols. The first was an incremental symptom limited treadmill test at heart rate 70, the second consisted of 12 minutes of walking at 40% of max exercise level at three pacemaker rates: 70, 100, 115. The third protocol had four exercise tests at submaximal exercise level, 6 minutes on treadmill at rate settings of 70,100,115,130.