The objective of this in vivo study is to investigate the effects of 337.1 nm pulsed N2 laser on cellular immune response represented by lymphocyte transformation capacity and phagocytosis activity in laboratory animals. The samples include 60 adult male BALB/c mice, were divided into control group and experimental groups. The experimental groups were divided into two main groups according to the time period after N2 laser irradiation. Each group was divided into 9 subgroups which exposed to N2 laser radiation at different values of pulse repetition rates and exposure times. The results of immunological tests demonstrated that the exposure to 180 J/cm2 of N2 laser radiation induce adverse effect to cellular immune response. The results of lymphocyte transformation assay showed that the capacity of lymphocyte to be transformed as response to mitogen PHA decreased only in subgroups that treated with 180 J/cm2. While in the other subgroups the percent of transformed lymphocyte cells was unaffected. The findings of phagocytosis assay showed that the activity of phagocytic cells increased only in subgroups that treated with 80 J/cm2, and decreased in subgroups that treated with 120 and 180 J/cm2.
In this work, results of a mathematical analysis of the role of workpiece preheating in laser keyhole welding were presented. This analysis considered the steady-state welding as well as certain range of boundary conditions over which preheating effect would be indicated. This work is an attempt to interpret the role of preheating to increase welding depth and perform keyhole welding with high quality using physical and thermal properties of steel alloys.
A Mini-TEA CO2 laser system was designed and operated to obtain a pulse at 10.6 μm. Output energy of 30 mJ, with preionization pins, and pulse duration of 100ns were obtained. While an output energy of 6mJ and pulse duration of 100 ns in absence of pre-ionization were obtained. The system was operated with Ernest profile main-discharge electrodes. Dependencies of supply voltage and output laser energy on the pressure inside laser cavity were investigated as well as dependencies of supply voltage and output energy on the main capacitor(8CO2 : 8N2 : 82He :2CO). Efficiency of was calculated to be 4.4%.
The propagation of laser beam in the underdense deuterium plasma has been studied via computer simulation using the fluid model. An appropriate computer code “HEATER” has been modified and is used for this purpose. The propagation is taken to be in a cylindrical symmetric medium. Different laser wavelengths (1 = 10.6 m, 2 = 1.06 m, and 3 = 0.53 m) with a Gaussian pulse type and 15 ns pulse widths have been considered. Absorption energy and laser flux have been calculated for different plasma and laser parameters. The absorbed laser energy showed maximum for = 0.53 m. This high absorbitivity was inferred to the effect of the pondermotive force.
The long healing time of bone after tooth extraction in order to construct artificial teeth is uncomfortable to the patient because of aesthetic or masticatory problems in addition to the daily visit to dental clinic. The objective of this study was to evaluate the effect of 805 nm diode laser with long time intervals on repair of bone and skin incisions in rabbits through biochemical, radiological and histological findings. Eighteen New-Zealand rabbits were undergone surgical operations to make a cavity in the bone of the lower jaw, the rabbits were divided into two groups:- Group A (control group) containing nine rabbits. Group B (lased group) containing nine rabbits in which two cavities were done, one on the right side and the other
... Show Moreتبحث هذه الدراسة في المهارات االتصالية عند المحررين الصحفيين وترتيب أولويات امتالكها لديهم إذ تلعب المهارات االتصالية دورا مهما في نجاح عملية التحرير الصحفي للرسالة بكل أنواعها سواء كانت خبرا أو مقاال أو تقريرا أو تحقيقا أو حديثا ، وتتنوع هذه المهارات بين األساسية المتعلقة باالتصال والمالحظة القوية وسرعة التعبير وبين المكملة لها المتعلقة باللغة والمعنى واإلرسال واالستقبال ، وتأتي هذه الد ارسة لتركز الضوء
... Show MoreThe microstructures of rapidly solidified laser clad layers of laser cladding of Inconel 617 with different nickel-aluminum premixed clad powders are discussed. The effect of different cladding speeds on the microstructures of rapidly solidified laser clad layers is discussed too. The detailed microstructural results showed that different growth mechanisms are produced during rapid solidification. These are planar, cellular, cellular/dendritic and dendritic.
In humans, Pseudomonas aeruginosa is the second most frequent gram negative nosocomial pathogen in hospitals and has the highest case-fatality rate of all hospital-acquired bacteremia because of the hardy resistance of these bacteria to mechanical cleansing as well as to disinfectant, and many antibiotics. The susceptibility of bacteria against the antibiotics is modulated by several local factors such as temperature which modified drug efficacy, so this study was carried out to evaluate the effect of different temperature (20,42,45)Ċon the susceptibility of Pseudomonas aeruginosa to the minimum inhibitory concentrations (MIC) of the antimicrobial agents before and after irradiation. The samples collected from 150 persons suffering from
... Show Moreتضمن البحث تحقيق مخطوط"، سرور الفؤاد بالصافنات الجياد في معرفة الخيل
وأسمائياالشيخ محمد العمري" وكما ظاىر من عنوان المخطوط إنوُ يتناول الخيل، والخيل
موضوع ميم في حياة العربي قبل الاسلام باعتباره يمثل جزءاً من تفاصيل حياتو الملازمة لوُ
واعتماده عمييا ىذا أولاً وثانياً ماتحمموُ الخيول من معاني الفروسية والعنفوان وماتثيره في
الأنسان من حب الأقتناع والمتعة المتحققة من النظر إلييا وحبو لمسبق،
The present study was conducted with a view to determine whether focal laser therapy result in visual recovery and regression of macular edema in patients with non proliferative diabetic retinopathy and maculopathy ,and whether combined focal and scatter laser therapy in patients with proliferative diabetic retinopathy and maculopathy results in visual recovery ,regression of macular edema and regression of the risk factors. In the present work, a frequency doubled Nd: YAG laser was used for the treatment of diabetic retinopathy. The study evaluates 41 eyes of 33 diabetic patients both with Insulin Dependent Diabetes Mellitus IDDM, (n=16) and Non Insulin Dependent Diabetes Mellitus NIDDM, (n=17) with diabetic retinopathy divided into two
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