to evaluate the effect of various Nd:YAG frequency doubled laser parameters on the acid
dissolution and the progression of in vitro caries like lesions in human enamel.
Materials and Methods: Human extracted caries free upper first premolar teeth were collected for
this study. The irradiated teeth were divided into two groups. The first group was irradiated with
continuous Nd:YAG laser radiation, and the second group was irradiated with chopped Nd:YAG laser
radiation. For the first group, power and exposure time were changed while for the second group
power and number of pulses were changed. The spot diameter was kept constant for all the samples.
Results: using 1.5 W and 3 seconds (exposure time), best results among the continuous group were
obtained, while in the chopped group using 1.5 W and 3 pulses gave better result. The percent
reduction in lesion depth in this study was up to 26% in the continuous group, whereas in the chopped
group was up to 44%.
يلعب القطاع الصناعي التحويلي في أي قطر دوراً هاماً في تحقيق التنمية الصناعية، اذ تتحد تاثيراته فيها على طبيعة الدور المرسوم له وعلى مدى فاعلية هذا القطاع الحيوي الذي يعد اتجاه نحو التعاظم المضطرد لمستويات الانتاجية " Levels of productivity"والتنويع الانتاجي والتدفق المستمر للتجديد التكنولوجي من اهم دلائله.
ويعد مؤشر الانتاجية بصفة عامة وانتاجيتي العمل وراس المال بصفة خاصة من الم
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The research aims to identify the magnitude of the impact of external debt on the gross domestic product in Morocco, and the importance of research lies in the role that external debt plays in addressing structural imbalances, if it is best disposed of according to well-studied economic plans by specialists in this regard, especially if these debts are directed with Other resources, as it helps pay the costs of these debts (debt servicing) that the external debt also raises the level of gross domestic product, and the research starts from the hypothesis that: There is an effect of foreign debt on the GDP in Morocco, has contributed in one way or another to The exacerbation of the external debt, which affected the m
... Show MoreThis paper investigates the performance evaluation of two state feedback controllers, Pole Placement (PP) and Linear Quadratic Regulator (LQR). The two controllers are designed for a Mass-Spring-Damper (MSD) system found in numerous applications to stabilize the MSD system performance and minimize the position tracking error of the system output. The state space model of the MSD system is first developed. Then, two meta-heuristic optimizations, Simulated Annealing (SA) optimization and Ant Colony (AC) optimization are utilized to optimize feedback gains matrix K of the PP and the weighting matrices Q and R of the LQR to make the MSD system reach stabilization and reduce the oscillation of the response. The Matlab softwar
... Show MoreThe residual limb within the prosthesis, is often subjected to tensile or fatigue stress with varying temperatures. The fatigue stress and temperatures difference which faced by amputee during his daily activities will produces an environmental media for growth of fungi and bacteria in addition to the damage that occurs in the prosthesis which minimizingthe life of the prosthetic limb and causing disconfirm feeling for the amputee.
In this paper, a mechanical and thermal properties of composite materials prosthetic socket made of different lamination for perlon/fiber glass/perlon, are calculated by using tesile test device under varying temperatures ( from 20oC to 60oC), also in this paper a device for measuring rotational bendin
... Show MoreBackground: Imaging techniques play a very important role in the specialty of endodontic. The ultrasonographic technique is non-expensive procedure, safe, and reproducible. The aim of the study was to determine the sensitivity, specificity, and accuracy of ultrasound and color Doppler ultrasonography in evaluation of periapical lesions (cyst, granuloma, mixed lesion “cyst within graulomas mass”, and abscess. Subject, Material and method: The sample consists of prospective study for 64 Iraqi participants who attended Karbalaa Specialized Center for Dentistry (males & females). Those patients were diagnosed clinically and radiographically as having periapical lesions of dental origin. They were examined by real time ultrasound and color
... Show MoreThere is a suggestion that an antidiuretic hormone-induced decrease in diuresis might contribute to the rapid relief of the acute pain in renal colic. This study was designed to evaluate the efficacy of desmopressin nasal spray compared with diclofenac given intramuscularly in patients with acute renal colic. The study included 75 patients randomized into three different groups; group A received desmopressin (40 μg, nasal spray), group B diclofenac (75 mg) intramuscularly and group C, both desmopressin and diclofenac. Pain was assessed using a visual analogue scale (a 10-cm horizontal scale ranging from `no pain' to `unbearable pain') at baseline, 10, 20 and 30 min after administering t
... Show MoreIn this study, two types of local plants were chosen, the first is the plant golden pothos Epipremnum aureum and the second is the Iraqi Sheikh's chin plant Tribulus terrestris L, for the purpose of making a comparison between them in terms of their possession of chemical groups with antioxidant activity in order to use them as a natural alternative to using antioxidants Industrial that cause negative effects on human health, the samples were prepared using the method of water and alcohol extraction (ethanol 70%) for both plants. It revealed the presence of a number of chemical groups (tannins, carbohydrates, phenols, flavonoids, alkaloids) for both plants, the aqueous and alcoholic extracts. Coumarins are only found in the sheikh's chin pl
... Show MoreThis study was conducted at the Poultry Research Station of the Agricultural Research Department/Ministry of Agriculture in Abu Ghraib for the period from 25/2/2019 to 7/4/2019 (42 days) with the aim of using several levels of Spirulina (SP)
Currently, there is no established of e-waste treatment in Thi- Qar province, while their creating is increasing every year. It has been well- known that e-waste is a source of environmental degrading and their placement in landfills increases the irreversible climate change. A research model has been developed to link three components: coercive pressure, normative influence, and mimicry, then study their effect on e-waste adopt and continuance intentions. The model was validated using data collected from a field survey of 92 managers of small enterprises in Thi-Qar province. A questionnaire was developed to collect data. It contains five major variables, exemplify by fourteen items. Als
... Show MoreIn this paper, Pentacene based-organic field effect transistors (OFETs) by using different layers (monolayer, bilayer and trilayer) for three different gate insulators (ZrO2, PVA and CYEPL) were studied its current–voltage (I-V) characteristics by using the gradual-channel approximation model. The device exhibits a typical output curve of a field-effect transistor (FET). Source-drain voltage (Vds) was also investigated to study the effects of gate dielectric on electrical performance for OFET. The effect of capacitancesemiconductor in performance OFETs was considered. The values of current and transconductance which calculated using MATLAB simulation. It exhibited a value of current increase with increasing source-drain voltage.