Background: The need for a rapid, noninvasive method for unwanted hair removal has led to the development of various light Sources for this purpose. Objective: To evaluate the efficacy of Intense Pulsed Light Source (IPLS) on unwanted hairs. Patients & Methods: In this open, uncontrolled clinical trial, 77 different anatomical areas in 34 referred patients to "Novin Didegan Clinic" in Tehran in 1380-1381, were treated by IPLS at fluencies ranging from 22 to 34 j/cm2 after their demographic data and the number of hairs were recorded. The 3 to 7 treatment sessions were accomplished 4 to 6 weeks apart. All of the patients were followed 6 months after the last therapy. The quantitative data were  analyzed by paired t test. Results: Six months after the last therapy, more than 50% reduction in number of hairs was noted in 80% of the treated areas; with mean reduction of 72±23 percent. Side effects were mild and reversible and occurred in ten patients. Conclusion: The IPLS appears to provide an effective and safe method for long term excess hair removal in various skin types.      

Background: The aim of this study is to explore the safety and diagnostic performance of dual-Source CT scan in comparison with single Source CT scan and conventional angiography in patients with coronary heart diseases.Materials and methods: A systematic review was performed using CRD standard methods. The Cochrane Library, MEDLINE, EMBASE, Google Scholar and TRIP were searched up to April 2009. The references of the marked studies and gray literature were also searched.Results: 17 articles were included. 9 articles reported the safety and 12 articles reported the diagnostic performance of DSCT.  Generally DSCT was a non-invasive and safe procedure.  Using DSCT the exposure of patient to X-ray was less than 64-slice single Source CT (SSCT) and more than conventional angiography. For the DSCT the mean sensitivity was 90.4%, mean specificity was 82%, mean PPV was 83% and mean NPV was 96%. For the SSCT the mean sensitivity was 90.4%, mean specificity was 82%, mean PPV was 83% and mean NPV was 96%. The mean sensitivity, specificity, PPV and NPV of DSCT were slightly higher than SSCT.Conclusion: DSCT is a noninvasive and relatively safe technology. The diagnostic performance of DSCT is higher than SSCT, but its performance is not so much high to be able to substitute the conventional invasive angiography which is still the gold standard test.

There is an increasing demand for low-cost single-phase DC– AC inverters in many applications such as PV systems. These systems may be used without the transformer to improve efficiency and make the whole system lighter, smaller, and easier to install. With the transformerless topology, the system efficiency may be increased by about 2%, and the related cost may be decreased by about 25%. There are large leakage currents in transformerless topologies, especially in photovoltaic systems, where safety issues and electromagnetic interference problems often occur. To overcome such disadvantages, common-ground topologies can be used as they can minimize the leakage current of the transformerless inverter ones. The transformerless semi-quasi-Z-Source inverter (SqZS) with the common-ground structure offers many advantages over conventional single-phase inverters. Leakage current elimination, higher power density, fewer components, and low-cost features make it an attractive option as a micro-inverter in photovoltaic applications. The basic topology of SqZSI is especially suitable for a PV module in low-voltage applications as a low-cost micro-inverter with high-voltage SiC switching devices. However, the unity voltage gain is one of the disadvantages of SqZS inverters, which is referred to as a drawback. In other words, the conventional structure of SqZS is not capable of stepping up the voltage, and the maximum amplitude of AC voltage that can be extracted is equal to the input DC voltage. This paper proposes a modified structure for single-phase inverters (MSqZS) to achieve voltage boost capability. The voltage boost is achieved in a single-stage conversion just by adding an additional series DC blocking capacitor to the basic inverter. It also maintains the common-ground feature. Nonlinear sinusoidal modulation (NLSPWM) is modified to allow the SqZS basic structure to achieve high voltage gain. Although the proposed inverter is modified in topology and modulation, it is not more complex than the basic SqZSI. The proposed inverter has the least number of components among the similar step-up common-ground topologies. In this paper, the closed-loop control is proposed to improve the performance of the MSqZS under variable input voltage, as well as output load and compensation for the undesired and non-ideal effect of the parasitic elements. In addition, the proposed inverter is capable of generating reactive power. Also, the design consideration for series capacitor is analysed for proper capacitor selection. The simulation and experimental results under various closed-loop and open-loop scenarios comply with the IEEE Std 1547 and verify the appropriate performance of the proposed inverter.

Today, solar energy, fuel cells and wind energy have attracted much attention as clean Sources of energy. These Sources can deliver energy either to the grid or directly to the consumer. The produced voltage level of these Sources is usually low and needs to be increased. This problem can be solved using switching converters. These converters should have the ability to provide high voltage gain. In this paper, a high step-up switching converter is presented based on z-Source technique. The proposed converter not only increases the voltage gain, but also reduces voltage and current stress of the switch, so, switches with small on-resistance cab be used which contributes to conducting loss reduction and efficiency improvement. Also, coupled inductors are used in this converter that reduces the circuit volume. At first, the operating modes of the proposed converter are analysed, then, an experimental prototype is designed, and the performance validity is investigated via simulation in PSPICE software. Finally, a practical sample of the proposed converter is implemented in 100 kHz and 200W output power. The obtained results verify the theoretical analysis as well as the correct performance of the proposed converter.