الهدف: كان الغرض من هذه الدراسة المختبرية هو تقييم فعالية ليزر الإربيوم والكروم: الإيتريوم سكانديوم الغاليوم باستخدام التدفق الصوتي الضوئي المستحث بالفوتون في تنشيط سوائل الري من خلال تقييم تأثيره في ابادة البكتريا في نظام الجذر المعقد الذي تم استعمارهه بالمكورات المعوية البرازية.
الطرق: تم فصل الجذور الاونسيه لـ 90 ضرساً سفلياً، وحقنها بمعلق المكورات المعوية البرازية (ما عدا عينات ا
... Show MoreSpider veins are a common aesthetic problem mainly in females , the conventional method of treatment is by microsclerotherapy (injections) but laser therapy has become increasingly efficacious and a convenient method for treatment. The present study was performed to investigate the effectiveness and safety of pulsed diode laser (810nm) by doing thermal photocoagulation. Ten patients with lower limbs spider veins were included in this prospective study. They were treated with a repetitive pulsed diode laser in non contact technique using the following laser parameters (wave length 810nm,power 1 W ,pulse duration 0.1 s., pulse interval 0.5 s, spot diameter 4mm ,power density 7.9 W/cm2). Laser therapy was performed on day zero and day fourt
... Show MorePhotonic crystal fiber interferometers (PCFIs) are widely used for sensing applications. This work presented solid core-PCFs based on Mach-Zehnder modal interferometer for sensing refractive index. The general structure of sensor was applied by splicing short lengths of PCF in both sides with conventional single mode fiber (SMF-28).To apply modal interferometer theory collapsing technique based on fusion splicing used to excite higher order modes (LP01 and LP11). A high sensitive optical spectrum analyzer (OSA) was used to monitor and record the transmitted wavelength. This work studied a Mach-Zahnder interferometer refractive index sensor based on splicing point tapered SMF-PCF-SMF. Relation between refractive index sensitivity and tape
... Show MoreThe influence of sensing element length of no-core fiber strain sensor has been studied and experimentally demonstrated, four different lengths of 125 μm diameter no-core fiber is fused between two standard single-mode fibers and bi-directionally strained, the highest obtained sensitivity was around 16.37 pm με -1 which was exhibited in the shortest no-core fiber segment, to the best of our knowledge this is the first study of the influence of no-core fiber strain sensors length on sensor sensitivity. The proposed sensor can be used in many opto-mechanical applications such as, structural health monitoring, aerospace vehicles and airplane components monitoring.
In this work a chemical sensor was built by using Plane Wave Expansion (PWE) modeling technique by filling the core of 1550 hollow core photonic crystal fiber with chloroform that has different concentrations after being diluted with distilled water. The minimum photonic bandgap width is.0003 and .0005 rad/sec with 19 and 7 cells respectively and a concentration of chloroform that filled these two fibers is 75%.
Patients are very concerned about the lengthy nature of orthodontic treatment. It is necessary to find a non-invasive way to quicken physiologic tooth movement. This study's objective was to assess the effectiveness of low-intensity laser therapy in shortening the time and discomfort of orthodontic treatment. Experimental work: Using a split-mouth study to compare tooth movement with conventional treatment and laser-accelerated orthodontic tooth movement. A patient presenting with a class II division I malocclusion characterized by the misalignment of the upper and lower teeth as classified by Angle’s molar classification system was indicated to undergo fixed orthodontic appliance orthodontic treatment. The treatment plan involved bila
... Show MoreRandom laser gain media is synthesized with different types of dye at the same concentration (1×10-3 M) as an active material and silicon dioxide NPs (silica SiO2) as scatter centers through the Sol-Gel technique. The prepared samples are tested with UV–Vis spectroscopy, Fluorescence Spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), and Energy Dispersive X-ray Diffraction (EDX). The end result demonstrates that doped dyes with silica nanoparticles at a concentration of 0.0016 mol/ml have lower absorbance and higher fluorescence spectra than pure dyes. FESEM scans revealed that the morphology of nanocrystalline silica is clusters of nano-sized spherical particles in the range (25-67) nm. It is con
... Show MoreThe objective of this study is to determine the efficacy of class V Er:YAG laser (2940 nm) cavity preparation and conventional bur cavity preparation regarding Intrapulpal temperature rise during cavity preparation in extracted human premolar teeth. Twenty non carious premolar teeth extracted for orthodontic purposes were used and class V cavity preparation was applied both buccal and lingual sides for each tooth .Samples were equally grouped into two major groups according to cavity depth (1mm and 2mm). Each major group was further subdivided into two subgroupsof ten teeth for each (twenty cavities for each subgroup). TwinlightEr:YAG laser (2940 nm) with 500mJ pulse energy, P.R.R of 10 Hz and 63.69 J/cm2 energy density was used. The ana
... Show MoreThis work presents the use of laser diode in the fiber distributed data interface FDDI networks. FDDI uses optical fiber as a transmission media. This solves the problems resulted from the EMI, and noise. In addition it increases the security of transmission. A network with a ring topology consists of three computers was designed and implemented. The timed token protocol was used to achieve and control the process of communication over the ring. Nonreturn to zero inversion (NRZI) modulation was carried out as a part of the physical (PHY) sublayer. The optical system consists of a laser diode with wavelength of 820 nm and 2.5 mW maximum output power as a source, optical fiber as a channel, and positive intrinsic negative (PIN) photodiode
... Show MoreBackground: Pyogenic granuloma is a hyperplastic benign tumor. The most common intra-oral site is marginal gingiva. It is often occurred in the second decade of life, it has a strong tendency to recur after simple excision.
The aim of study: to evaluate the therapeutic advantages of diode laser (810-980 nm) in intraoral Pyogenic granuloma management.
Materials and method: A total of 28 patients (14 men and 14 females) were enrolled in this study and had their pyogenic granuloma surgically removed using a diode laser. All of the patients were given local anesthetic and went through the identical surgical procedure (cartridge containing 1 percent lidocaine with epinephrine 1:
... Show Moreالخلفية: الورم الليفي العصبي الضفري [PN] هو ورم غير خبيث يؤثر على غمد الأعصاب الطرفية ويرتبط مع الورم الليفي العصبي من النوع 1 [NF1.1]. وقد ظهر العلاج بالليزر كنهج فعال محتمل لإدارة الأورام الليفية العصبية الضليعية الفموية، مما يجعلها أداة تشخيصية قيمة في مجال طب الأسنان.
عرض دراسة حالة: مريض ذكر، يبلغ من العمر 60 عامًا، تم تشخيصه بالإصابة بالورم الليفي العصبي من النوع الاول، أظهر تورمًا غير م
... Show Moreتوفر طرق طبة المسحوق, بما في ذلك الصهر بالليزر الانتقائي و تنوعا كثيرا في كل من عمليات التصميم والتصنيع. ومع ذلك , فأن القيد الحالي لهذه الطريقة يكمن في قدرتها على انتاج أجزاء من مادة واحدة. بالنسبو لمتطلبات المواد المتعددة المعقدة مثل عمليات الطلاء. تتضمن الحلول المثالية تكاملا مخصصا للمواد المتنوعة المطلوبة للتحكم في عملية الذوبان والتصلب داخل واجهة المعادن المختلفة. في هذه الدراسة, تم أنشاء نموذج ديناميك
... Show Moreالهدف : الأسباب الأكثر شيوعا في فشل ارتباط الوتد الليفي هو الترميم الغيركافي والازاحه. التركيب السطحي للوتد الليفي يتأثر
بواسطة إشعاع الليزر وقد يعزز من قوة التصاقه. في هذه الدراسة الاستطلاعية نناقش تأثيرليزر Er,YAG وليزر Er,CR:YSGG على سطح الوتد الليفي وقوة التصاقه بالاسمنت الراتنجي في الأسنان المعالجة لبيا .
الطرق : تم بحث شامل في مقالات محرك كوكل و PubMed و Medline و Web of Science نشرت من 2013 إلى
2023 و
Fractional Er: YAG laser resurfacing is increasingly used for treating rhytides and photo aged skin because of its favorable benefit‐risk ratio. The multi-stacking and variable pulse width technology opened a wide horizon of rejuvenation treatments using this type of laser. To evaluate the efficacy and safety of the use of fractional 2940 nm Er: YAG laser in facial skin rejuvenation. Twelve female patients with mean age 48.3 years and multiple degrees of aging signs and solar skin damages, were treated with 2 sessions, one month apart by fractional Er: YAG laser. Each session consisted of 2 steps, the first step employed the use of the multi stack ablative fractional mode and the fractional long pulsed non-ablative mode settings were u
... Show MoreA 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%.
Low-intensity laser irradiation has been explored as an alternative, non-invasive method to encourage chronic wounds to heal. This study aimed to evaluate the effects of low level laser therapy (biostimulation) using semiconductor diode laser with wavelength (785 nm) on the enhancement of chronic wound healing. Fifty patients with chronic wounds were selected to be treated with Low Level Laser Therapy. Their ages ranged between 1 to 76 years. The wound sites were distributed in the lower limb, upper limb, trunk , perineum and head (70%,14%,12%,2%,2%, respectively). Application of laser therapy by noncontact method few millimeters from the skin for 15 minutes per one session twice weekly for two months ; ie,16 sessions for each patient. R
... Show MoreIn this study, a mathematical model is presented to study the chemisorption of two interacting atoms on solid surface in the presence of laser field. Our mathematical model is based on the occupation numbers formula that depends on the laser field which we derived according to Anderson model for single atom adsorbed on solid surface. Occupation numbers formula and chemisorption energy formula are derived for two interacting atoms (as a diatomic molecule) as they approach to the surface taking into account the correlation effects on each atom and between atoms. This model is characterized by obvious dependence of all relations on the system variables and the laser field characteristics which gives precise description for the molecule –
... Show MoreIn this study, the effect of Nd: YAG laser on the activity of superoxide dismutase (SOD) and alcoholdehydrogenase (ADH) was investigated. The Saccharomyces cells were irradiated using 532nm Q-Switched Nd: YAG laser with (1Hz) frequency. Different fluences 11.3, 22.6 and 33.9mJ/cm2 and different number of pulses 15, 30 and 60 pulse were used. The irradiated cells were incubated in a liquid nutritive medium for 24 hours. After incubation, the cells were harvested and disrupted to extract the intracellular enzymes and their activities were assessed. In comparison with the control, the irradiated cells showed a significant increase in the activity and the specific activity of SOD at energy densities of 11.3 and 22.6mJ/cm2 at 30 and 60 pulses
... Show Moreالهدف: الهدف من البحث الحالي هو كشف الأنياب المنطمرة في الشدق العلوي باستخدام ل يزر الدايود ) 810 + 980 ( نانومتر) في مقارنة الأنياب المنطمرة حنكي ا اعتماد ا على هذه العوامل الألم، الورم، زمن الشفاء(. المقدمة: يوفر ليزر الصمام الثنائي( 810 + 980) اختراق ا عميق ا للأنسجة الرخوة وتخثر الدم وتجلط الدم بشكل ممتاز ولديه الحد الأدنى من التفاعل مع أنسجة الأسنان الصلبة .
المواد والطرق: جميع المرضى الذين يعا
تقدم هذه الدراسة مستشعرًا يستخدم تقنية الألياف الكريستالية الضوئية ( PCF ) وتقنية رنين البلازمون السطحي ( SPR ). تم تطبيق الذهب ( Au ) كطبقة رقيقة على ألياف كريستالية ضوئية ( PCF )، والتي كانت مغلفة سابقًا بمركب ذهبي
مستقر كيميائيًا يُظهر خصائص بلازمونية. كان سمك طلاء الذهب 40 نانومتر. تم تقييم مقاييس الأداء، مثل الحساسية بما في ذلك حساسية الطول الموجي وحساسية السعة والقرار، عن طريق المحاكاة عبر برنامج COMSOL . تم تطوي
تطوير مستشعر لقياس التغير في معامل الانكسار للمحيط باستخدام تقنية مستشعر الألياف غير النواة على شكل حرف (D) .يتكون هذا المستشعر من قطعة من الألياف غير النواة ) CF ( ملحومة بين ليفين أحادي النمط ) SMF (. تم تلميع منتصف طول الألياف غير النواة باستخدام عجلة طحن لتقليل القطر من جانب واحد، مما أدى إلى إنشاء مقطع عرضي على شكل حرف D .تم اختبار أداء مستشعر DSCF باستخدام تركيزات مختلفة من محاليل كلوريد الصوديوم ( NaCl)، حيث تتراوح
... Show Moreيتعامل هذا البحث مع تقييم النشاط المضاد للسرطان لتوليف Ag/Au NPs بواسطة نظام هجين يجمع بين تقنية الليزروالبلازما النفاثة. تمت دراسة تأثير NPs على تثبيط نمو خلايا سرطان الثدي وخط الخلايا الطبيعية. أولاً، تم تحضير الجسيمات النانوية الفضية باستخدام ليزر Nd:YAG بطول موجي 1064 نانومتر، وتردد 6 هرتز، وطاقة 1000 مللي جول، وعدد من النبضات 558 . الخطوة الثانية، نأخذ نسبًا مختلفة بين Ag NPs وأملاح الذهب على النحو التالي: ( 1:9 و 2:8 و 3:7 )،
... Show Moreالخلفية: مصطلح الناسور العصعصي يشير إلى حالة موجودة في منطقة الشق الولادي فوق العصعص. يحتوي الناسور العصعصي (الشعري) عادة على الشعر والأوساخ والأنسجة الحبيبية غير الصحية. يسبب الناسوؤ العصعصي معاناة شديدة ، وفي الغالب تحدث عدوى واخماج فيه، مما يؤدي إلى تسرب القيح ذو رائحة كريهة. معدل الإصابة بين الذكور2.2 - 4 مرات أعلى منها بين الإناث. تتميز المرحلة الحادة بوجود خراج عجزي، في حين خلال المرحلة المزمنة ي
... Show MoreAbstract: Background: Optical biosensors offer excellent properties and methods for detecting bacteria when compared to traditional analytical techniques. It allows direct detection of many biological and chemical materials. Bacteria are found in the human body naturally non-pathogenic and pathologically, as they are found in other living organisms. One of these bacteria is Escherichia coli (E. coli) which are found in the human body in its natural and pathogenic form. E.coli bacteria cause many diseases, including Stomach, intestines, urinary system infections, and others. The aim of this study: is sensing and differentiation between normal flora and pathogenic E.coli. Material and method:
... Show MoreAbstract: Background: Staphylococcus aureus is Gram-positive bacteria that lives as a normal flora in living organisms but can be pathogenic to humans. Although a relatively unspectacular, nonmotile coccoid bacterium, S. aureus is a dangerous human pathogen in both community-acquired and nosocomial infections. Due to the increasing emergence of new strains of this antibiotic-resistant bacteria, it has become essential to approach different methods to control this pathogen. One of these methods is the antimicrobial photodynamic inactivation process using a low-level laser, in this paper, the Photodynamic effects of Rose Bengal and LLLL on the virulence factors of S.aureus were evaluated.
Among the different passive techniques heat pipe heat exchanger (HPHE) seems to be the most effective one for energy saving in heating ventilation and air conditioning system (HVAC). The applications for nanofluids with high conductivity are favorable to increase the thermal performance in HPHE. Even though the nanofluid has the higher heat conduction coefficient that dispels more heat theoretically but the higher concentration will make clustering .Clustering is a problem that must be solved before nanofluids can be considered for long-term practical uses. Results showed that the maximum value of relative power is 0.13 mW at nanofluid compared with other concentrations due to the low density of nanofluid at this concentration. For highe
... Show MoreIn this work, nanostructure zinc sulfide (ZnS) thin films at temperature of substrate 450 oC and thickness (120) nm have been produced by chemical spray pyrolysis method. The X-Ray Diffraction (XRD) measurements of the film showed that they have a polycrystalline structure and possessed a hexagonal phase with strong crystalline orientation of (103). The grain size was measured using scanning electron microscope (SEM) which was approximately equal to 80 nm. The linear optical measurements showed that ZnS nanostructure has direct energy gap. Nonlinear optical properties experiments were performed using Q-switched 532 nm Nd:YAG laser Z-scan system. The nonlinear refractive index (n2) and nonlinear absorption coefficient (β) estimated for Z
... Show MoreBackground: Laser urinary stone lithotripsy is an established endourological modality. Ho:YAG(2100nm) laser have broadened the indications for ureteroscopic stone managements to include larger stone sizes throughout the whole urinary tract.
Purpose: To evaluate the effectiveness and safety of Holmium: YAG(2100nm) laser lithotripsy with a semirigid uretero scope for urinary stone calculi in a prospective cohort of 17 patients.
Patients and Methods: Holmium: YAG(2100nm) laser lithotripsy was performed with a semirigid ureteroscope in 17 patients from September 2016 to December 2016. Calculi were located in the lower ureter in 9 patients (52.9%), the midure
... Show MoreFiber Bragg Grating has many advantages where it can be used as a temperature sensor, pressure sensor or even as a refractive index sensor. Designing each of this fiber Bragg grating sensors should include some requirements. Fiber Bragg grating refractive index sensor is a very important application. In order to increase the sensing ability of fiber Bragg gratings, many methods were followed. In our proposed work, the fiber Bragg grating was written in a D-shaped optical fiber by using a phase mask method with KrFexcimer. The resultant fiber Bragg grating has a high reflectivity 99.99% with a Bragg wavelength of 1551.2 nm as a best result obtained from a phase mask with a grating period of 1057 nm. In this work it was found that the rota
... Show More: In modern optical communication system, noise rejection multiple access interference (MAI) must be rejected in dense access network (DAN). This paper will study the dual optical band pass and notch filters. They will be extracted with tunable FWHM using 10cm (PMF) with different cladding diameters formed with etching 125μm PMF after immersing it with 40% of hydrofluoric acid (HF). This fiber acts as assessing fiber to perform Sagnac interferometer with splicing regions that placed 12cm (SMF) for performing hybrid Sagnac interferometer that consists of Mach-Zehnder instead of Sagnac loop which is illuminated by using laser source with centroid wavelength of 1546.7nm and FWHM of 286 pm or 9 ns in the time domain. . Firs
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