Background: The treatment of dental tissues proceeding to adhesive procedures is a crucial step in the bonding protocol and decides the clinical success ofrestorations. This study was conducted in vitro, with the aim of evaluating thenanoleakage on the interface between the adhesive system and the dentine treated by five surface modalities using scanning electron microscopy and energydispersiveX-ray spectrometry. Materials and methods: Twenty five extracted premolars teeth were selected in the study. Standardized class V cavities were prepared on the buccal and lingual surfaces then the teeth divided into five main groups of (5 teeth in each group n=10) according to the type of dentine surface treatment that was used: Group (A): dentine was conditioning with Er, Cr: YSGG laser. Group (B): dentine was conditioning with (Er, Cr: YSGG laser + acid). Group (C): dentine was conditioning with (acid + Er, Cr: YSGG laser). Group (D): dentine was conditioning with acid etch. Group (E): dentine was conditioning with acid + 10% sodium hypochlorite. For All the teeth SBMP adhesive were used and restored with Z250 composite restoration then all specimens were subjected to thermocycling 500 cycles, at 5° to 55 °C. The teeth were soaked in silver nitrate suspension. Then the teeth sectioned bucco-lingually across the centre of the restorations. The specimens were characterized using scanning electron microscopy and the amount of nanoleakage was measured by EDX spectro-analysis to identify the existence of metallic silver particles. Results: Data were analysed statistically by one way ANOVA test and (LSD) Tests. The results showed that there were statistically highly significant differences among all groups of the present study.The resultshowed that the acid and laser (group III) exhibited the lowest mean value of nanoleakage at around (6.14 %), whereas the highest mean value of nanoleakage (12.83 %) was determined by the only acid (group IV). Conclusions: Treating the acid etched dentine with Er: Cr: YSGG laser showed promising results as it exhibits lowest amount of nanoleakage of the adhesive bonding system.
In this work, the switching nonlinear dynamics of a Fabry-Perot etalon are studied. The method used to complete the solution of the differential equations for the nonlinear medium. The Debye relaxation equations solved numerically to predict the behavior of the cavity for modulated input power. The response of the cavity filled with materials of different response time is depicted. For a material with a response time equal to = 50 ns, the cavity switches after about (100 ns). Notice that there is always a finite time delay before the cavity switches. The switch up time is much longer than the cavity build-up time of the corresponding linear cavity which was found to be of the order of a few round-trip ti
... Show MoreIn this research the hard chromium electroplating process, which is one of the common methods of overlay coating was used, by using chromium acid as source of chromium and sulphuric acid as catalyst since the ratio between chromic acid and sulphuric acid is (100 : 1) consequently. Plating process was made by applying current of density (40 Amp / dm2) and the range of solution temperature was (50 – 55oC) with different time periods (1-5 hr). A low carbon steel type (Ck15) was used as substrate for hard chromium electroplating. Solid carburization was carried out for hard chromium plating specimen at temperature (925oC) with time duration (2 hr) to be followed with quenching and tempering
... Show MoreCalcium-Montmorillonite (bentonite) [Ca-MMT] has been prepared via cation exchange reaction using benzalkonium chloride [quaternary ammonium] as a surfactant to produce organoclay which is used to prepare polymer composites. Functionalization of this filler surface is very important factor for achieving good interaction between filler and polymer matrix. Basal spacing and functional groups identification of this organoclay were characterized using X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy respectively. The (XRD) results showed that the basal spacing of the treated clay (organoclay) with the benzalkonium chloride increased to 15.17213 0A, this represents an increment of about 77.9% in the
... Show MoreCubosomes are nanosized structures self-assembled nanostructured materials used for controlling the release of the entrapped drug molecule. Lornoxicam (LXM) is a potent analgesic nonsteroidal anti-inflammatory (NSAID) drug with a short half-life (3-4) hours. The present study aims to prepare LXM-loaded cubosomes with well-defined morphology, particle size, PDI, high entrapment efficiency, sustained drug release, and high zeta potential value, as a transdermal drug delivery system.
Twelve formulas of LXM-loaded cubosomal dispersions were prepared by a solvent dilution method using Glyceryl monooleate ( GMO) as polar lipid with different stabilizers as Pluronic® F127 or tween 80 and different types o
... Show MorePatch in transdermal drug delivery(TDDS) used to overcome the hypodermic drawback, but these patch also have absorption limitation for hydrophilic and macromolecule like peptide and DNA. So that micronized projection have the ability for skin penetration developed named as microneedle. Microneedle drug delivery system is a novel drug delivery to overcome the limitation of TDDS like skin barrier restriction for large molecule. Microneedle patch can penetrate through skin subcutaneous into epidermis, avoiding nerve fiber and blood vessel contact. There are many type of microneedle patch like solid, polymer, hallow, hydrogel forming microneedle and dissolving microneedle with different method of microfabrication
Background: coronavirus 19 is a beta-coronavirus, enveloped and roughly spherical with approximately 60 to 140 nm in diameter with positive-sense single-stranded RNA genome.
Objectives: Measurement of interleukin 6 (IL6) level in a group of patients with confirmed Covid19 infection and its correlation with many hematological and biochemical parameters , mainly lymphocyte , neutrophil count and their ratio , platelet count , serum ferritin , C reactive protein as well as D-dimer level
Subjects and Methods: This study was conducted on 60 PCR positive patients variably affected by COVID-19 , cases collected sequentially from June till November 20
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This study aimed to identify the business risks using the approach of the client strategy analysis in order to improve the efficiency and effectiveness of the audit process. A study of business risks and their impact on the efficiency and effectiveness of the audit process has been performed to establish a cognitive framework of the main objective of this study, in which the descriptive analytical method has been adopted. A survey questionnaire has been developed and distributed to the targeted group of audit firms which have profession license from the Auditors Association in the Gaza Strip (63 offices). A hundred questionnaires have been distributed to the study sample of which, a total of 84 where answered and
... Show MoreGroundwater is an important resource that can be used for various purposes. Various factors can change the chemistry of the GW, such as the chemical composition of an aquifer as well as the leaching of human waste into groundwater. The study area is a barren land covered by some sabkhas, in addition to some agricultural fields. The study aims to assess groundwater quality for drinking purposes using the Water Quality Index. The groundwater is chemically heterogeneous and has a wide quality range from very poor to excellent. Evaporation appears to be the controlling factor among the other shallow waters, while relatively deep water is related to rock-soil dominance. Rocks, land use and land cover have helped control the groundwater q
... Show MoreThis paper deals with finite element modeling of the ultimate load behavior of double skin composite (DSC) slabs. In a DSC slab, shear connectors in the form of nut bolt technique studs are used to transfer shear between the outer skin made of steel plates and the concrete core. The current study is based on finite element analysis using ANSYS Version 11 APDL release computer program. Experimental programmes were carried out by the others, two simply supported DSC beams were tested until failure under a concentrated load applied at the center. These test specimens were analyzed by the finite element method and the analyses have shown that these slabs displayed a high degree of flexural characteristics, ultimate strength,
... Show MoreThe aim of this study is to screen the phytochemicals found in Populus euphratica leaves since this type of trees are used traditionally by many villagers as treatment for eczema and other skin disease and also this plant is poorly investigated for their phytochemicals especially in Iraq. Phytochemical screening of the extracts obtained from the n-hexane and chloroform fraction of leaves of Populus euphratica was done by Thin-layer chromatography and various spraying reagents to test if alkaloids, sterols and other compounds are present. UPLC-electrospray ionization –tandem mass spectroscopy along with GC-MS and HPTLC are used to identify the phytochemicals present in the plant leaves.UPLC-ESI-MS/MS method 20 compound
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