Laser drilling is capable of producing small, precisely positioned holes with high degree of reproductively. In this paper , IR millisecond Nd:YAG single pulsed laser was used to determine the effect of laser parameters on the drilled hole of the glass - fiber reinforced epoxy composite FR-4 sample of 2 mm in thickness . The type of laser source was GSI lumonics JK760TR Series laser 1.064μm system in a CNC cabin. The JK760TR series has a 0.3-50ms pulse length and a maximum repetition rate 500Hz with an average power of 600W. The investigation of single pulse laser drilling in this paper was based on theoretical and experimental solutions. In single pulse technique, the investigation included focal plane position fpp, pulse shape, laser peak power, and pulse duration. It was found that (-1) was the best fpp due to less taper for the drilled holes made by this level (Entrance hole =0.68, Exit hole = 0.27). To predict pulse shape effects; three types were : rectangular , rump-up and cool down, it were examined found that rectangular pulse was efficient more than the other types due to its ability to produce holes with less tapering as compared with others types. Also its found that all pulse shapes had the same effect on the materials microstructure . Laser peak power and pulse duration had the predominant affects on the hole dimensions and edge quality without any defect except hole tapering.
Background and Aim. Coronary artery disease (CAD) is a major risk factor for the progression to heart failure (HF), which is associated with an increase in left ventricular volume (LVV). This study aims to measure ventricular function and myocardial perfusion imaging markers of the left side of the heart, which can be performed with injection of a 99mTc at stress and rest by using single-photonemission-computed-tomography (SPECT). Subject and methods. The study included 121 patients with CAD, comprising 53 females and 68 males with ages between 25 to 88 years and 265 healthy subjects comprising 84 males and 181 females. All patients and healthy subjects volunteered to participate in this study. They were classified according to
... Show MoreThose interested in the educational process and lesson management sought to invest the information experience with industrial intelligence and technology because of its importance in increasing the effectiveness of lesson management and developing the creative capabilities of the teacher in directing and managing his lesson. Field research for sports educational institutions that are interested in managing the lesson and preparing mathematical teaching cadres is an important issue and necessary means for identifying the most important phenomena that accompany the process of managing the educational process, as the teacher's success in providing the appropriate conditions to provide rich and influencing experiences in managing and directing
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Background Fibroblast growth factor receptor 2 (FGFR2) and trinucleotide repeat-containing 9 (TNRC9) gene polymorphisms have been associated with some cancers. We aimed to assess the association of FGFR2 rs2981582 and TNRC9 rs12443621 polymorphisms with hepatocellular cancer risk. Methods One hundred patients with HCV-induced HCC, 100 patients with chronic HCV infection, and 100 controls were genotyped for FGFR2 rs2981582 and TNRC9 rs12443621 using allele-specific Real-Time PCR analysis. Results FGFR2 rs2981582 genotype TT was associated with increased risk of HCC when compared to controls (OR = 3.09, 95% CI = 1.24–7.68). However, it was significantly associated with a lower risk of HCC when using HCV patients as controls (OR =
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Mutations in genes encoding proteins necessary for detoxifying oxidative stress products have been predicted to increase susceptibility to lung cancer (LC). Despite this, the association between waterpipe tobacco smoking (WP), genetic polymorphisms, and LC risk remains poorly understood. This is the first study to explore the relationship between WP tobacco smoking and these genetic factors. Previously, we investigated the association of GSTP1 SNPs (rs1695-A/G and rs1138272-C/T) with LC in Iraqi males who smoke WP. Here, we expanded our analysis to include GSTM1 (active/null) and GSTT1 (active/null) genotypes, both individually and in combination with GSTP1 SNPs. Multiplex PCR and RFLP-PCR assays were utilized to determine the genotypes of
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The aim of this research is to construct a cognitive behavior program based on the theory of Meichenbaum in reducing the emotional sensitivity among Intermediate school students. To achieve the aims of the research, two hypotheses were formulated and the experimental design with equal groups was chosen. The population of research and its sample are determined. The test of negative emotional sensitivity, which is constructed by the researcher, was adopted. The test contains (20) items proved validity and reliability as a reliable test by presenting it to a group of arbitrators and experts in education and psychology. An educational program is constructed based on the theory of Meichenbaum. The test was applied to a sample of (60) second i
... Show MoreCharge transfer in styryl dyes STQ-1, STQ-2,and STQ-3 with organic media system has been studied theoretically depending on the Franck- Condon rule and continuum dielectric model . The reorientation energies (eV) were evaluated theoretically depending on dipole momentum, dielectric constant , and refrective index n. The rate constant of charge transfer has been calculated depending on the reorientation energy (eV) ,effective free energy , potential height barrier , and coupling coefficient . A matlap program has been written to calculated the rate constant of charge transfer and other parameter. The results of calculations show that STQ-2 dye is more reaction for charge transfer compare with STQ-1 and STQ-3 dyes
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