In this research work, single mode operation based on injection of a CW laser beam into a TEA CO2 laser cavity has been demonstrated. The technique has vast applications in research programs for laser spectroscopy and optical pumping. The observed smooth pulse shapes indicated that the system is operating in a single mode of operation, where no additional PZT mounted elements or other cavity stabilizing devices have been used. In addition, it has been observed that the output energy has not been reduced when the laser was operating in a single mode of operation, compared with the case when the laser is operating in the multi-mode regime.

Background: Proximal tibial fractures account for 1% of all fractures. Different treatments have been proposed for this fracture. Objectives: The present study aims to evaluate the clinical and radiological results of singleLOCKING and double-LOCKING plate fixation methods in patients with proximal tibial fractures. Methods: The present study was carried out on 40 patients with proximal tibial fractures referred to Imam Khomeini Hospital in Sari, Iran. They were divided into two groups of double-LOCKING fixation with 3. 5-mm LOCKING Compression Plate (LCP) and single-LOCKING fixation with 4. 5-mm LCP. They were followed up for at least 6 months after surgery. At the time of admission, they were assessed using Lysholm Knee Scoring Scale and Visual Analogue Scale. Radiographs were taken from all patients and the articular surface, and fracture healing, . Results: Of 40 patients, 17 and 23 were treated with 3. 5-mm and 4. 5-mm LCPs, respectively. The mean Lysholm score in the groups with 3. 5-mm and 4. 5-mm LCPs was 84±, 8. 2 and 78. 3±, 16. 2, respectively. There was no statistically significant difference between the two groups (P>0. 5). Conclusion: The radiological and functional outcomes were almost the same for single-LOCKING and double-LOCKING plate fixation methods. Both methods can be used to treat the tibial plateau fracture. The treatment can be selected according to the surgeon and the patient’, s request.

An (m = 2)/(n = 1) locked mode has been observed in Iran-Tokamak1 (IR-Tl) at safety factor q = 2.5 during the plasma current flattop phase, and in this paper its main characteristics have been studied. It has also been shown that investigating the precursor phase of disruption maylead to predication of the disruption.

This paper presents a novel approach to obtain fast LOCKING PLL by embedding a nonlinear element in the loop of PLL. The nonlinear element has a general parametric Taylor expansion. Using genetic algorithm (GA) we try to optimize the nonlinear element parameters. Embedding optimized nonlinear element in the loop shows enhancements in speed and stability of PLL. To evaluate the performance of the proposed structure, various tests performed and results compared with standard phase locked loop. The tests and results show the superior performance of the proposed PLL.

LOCKING compression plate (LCP) is a common orthopedic instrument for internal fixation and healing of bone trauma. It is important to study on mechanical behavior and failure investigation of LCP because its failure leads to lots of cost and pain to the patient. In this paper, fatigue life of an eight-hole tibia LCP is evaluated under flexural loading. A four-point bending jig is manufactured and fatigue tests are performed for different compression loads. Fatigue life cycles are investigated for compression loads of 500, 600, 700, 800, 900 and 1000 N and relation between compression load and life cycles is estimated. 125 walking days is estimated for the patient during treatment period according to life cycle results. Post failure analysis results on fracture surface revealed that the crack initiated from the edge of compression hole and propagated from lower to the upper surface of LCP according to beach marks. Finally, Scanning electron microscopy (SEM) on the fracture surface revealed striations as a proof of fatigue crack growth. The striation spacing near the crack initiation site is found to be smaller than this spacing far from the initiation zone. The fatigue crack propagation life is estimated as 1600 cycles according to the number of striation spacings.