23 research outputs found

    Evaluation of Tensile Strength and Microhardness of Two Nickel- Chromium Based Casting Alloys with the Addition of Different Ratios Recasted Alloy Using Oxyacetylene Flame Casting Techniques

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    The objective of this study is to evaluate the tensile strength and microhardness of Ni-Cr alloy by adding two different ratios of recasted alloy (25%,50%)and one controlled group (100%fresh alloy),some technicians in our country modifies the casting of Ni-Cr alloy by adding recasted alloy because of high cost of Ni-Cr and low economical state. We use two different trade mark of Ni-Cr alloy (wiron99 and maxwhiteness). According to ANSI/ADA Specification No. 14 (ISO 6871); 30 specimens were made for tensile testing for each alloy type. Another 30 specimens were made for micro-hardness testing which they were square in shape (6mm for each arm and 1mm thickness). ,after statistical analysis it was found that there were no significant differences between each sub-group for the same alloy type for tensile and micro-hardness testing specimens. Although there were a great significant differences between each alloy type

    Efficient Photocatalytic Degradation of Organic Pollutant in Wastewater by Electrospun Functionally Modified Polyacrylonitrile Nanofibers Membrane Anchoring TiO2 Nanostructured.

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    YesIn this study, polyacrylonitrile (PAN_P) nanofibers (NFs) were fabricated by electrospinning. The PAN_P NFs membrane was functionalized with diethylenetriamine to prepare a functionalized polyacrylonitrile (PAN_F) NFs membrane. TiO2 nanoparticles (NPs) synthesized in the laboratory were anchored to the surface of the PAN_F NFs membrane by electrospray to prepare a TiO2 NPs coated NFs membrane (PAN_Coa). A second TiO2/PAN_P composite membrane (PAN_Co) was prepared by embedding TiO2 NPs into the PAN_P NFs by electrospinning. The membranes were characterized by microscopic, spectroscopic and X-ray techniques. Scanning electron micrographs (SEM) revealed smooth morphologies for PAN_P and PAN_F NFs membranes and a dense cloud of TiO2 NPs on the surface of PAN_Coa NFs membrane. The attenuated total reflectance in the infrared (ATR-IR) proved the addition of the new amine functionality to the chemical structure of PAN. Transmission electron microscope images (TEM) revealed spherical TiO2 NPs with sizes between 18 and 32 nm. X-ray powder diffraction (XRD) patterns and energy dispersive X-ray spectroscopy (EDX) confirmed the existence of the anatase phase of TiO2. Surface profilometry da-ta showed increased surface roughness for the PAN_F and PAN_Coa NFs membranes. The adsorption-desorption isotherms and hysteresis loops for all NFs membranes followed the IV -isotherm and the H3 -hysteresis loop, corresponding to mesoporous and slit pores, respectively. The photocatalytic activities of PAN_Coa and PAN_Co NFs membranes against methyl orange dye degradation were evaluated and compared with those of bare TiO2 NPs.The higher photocatalytic activity of PAN_Coa membrane (92%, 20 ppm) compared to (PAN_Co) NFs membrane (41.64%, 20 ppm) and bare TiO2 (49.60%, 20 ppm) was attributed to the synergy between adsorption, lower band gap, high surface roughness and surface area

    The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set

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    Background Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables. Methods Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set. Results Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15–0.23), higher ASA scores (OR 0.19, 95% CI 0.15–0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58–0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48–0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34–0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of ≀5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (p < 0.001). Conclusions The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy

    Dynamics of solitary waves, chaotic behaviors, and Jacobi elliptic wave solutions in telecommunication systems

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    This research explores bifurcation of a nonlinear model concerning with the telecommunication strait. Possible all phase plane diagrams due to various parametric conditions are found. Derivation of analytical tangled wave propagating solutions following all phase orbits of the corresponding phase portraits are established. As a results, the soliton, shock wave, singular soliton, periodic wave and singular periodic solutions are obtained by direct integration from Hamiltonian energy function. The periodic solutions of the model are formulated in the form of generalized Jacobi elliptic functions, which also provide the solitonic solution setting the value of beta is unity. Additionally, chaotic and quasi-periodic behaviors have been found for a range of parameter values after adding the perturbed term. The perturbed system’s quasi-periodic and chaotic behavior have been demonstrated using sensitivity analysis. Finally, picturesque explorations are delivered exposing effects of exist parameters of the gained wave solutions. The majority of the achieved results are derived for the first time. Moreover, the solutions show that the novel schemes are very simple, outright, fruitful and successful and that they can be used in wide range of other nonlinear partial differential equations (NLPDEs), which create different kinds of dynamical features of other wave model

    Synthesis, characterization, and miRNA-mediated PI3K suppressing activity of novel cisplatin-derived complexes of selenones

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    New therapeutic options are crucially for most cancers, particularly those with poor clinical outcomes. Five new derivatives of cisplatin-containing selenone ligands with the general formula, cis-[Pt(NH3)2(Selenone)2](NO3)2 (1–5) were synthesized and characterized using elemental analysis, Infrared, and nuclear magnetic resonance (1H, 13C &amp; 77Se) spectroscopy. Spectroscopic and computational data supported the coordination of selenones to platinum(II). The structures of the complexes were predicted using density functional theory calculations. Molecular docking studies were carried out using the AutoDock Tools docking program. The in vitro cytotoxicity of these complexes and cisplatin against three human cancer cell lines, HeLa, A549, and HCT116 was investigated using the MTT assay. The best candidate complex, complex 3, was subjected to mechanistic assessments, including miRNA profiling, PI3K deactivation, and induction of apoptosis. Docking studies showed that all the newly synthesized platinum(II) complexes interacted with the minor DNA groove. The synthesized complexes showed promising cytotoxic effects against the tested cell lines. Complex 3 modulated the miRNA expression signature in A549 cells. Pathway enrichment analyses of differentially expressed miRNA gene targets identified the PI3K/AKT signaling pathway as a promising target. Complex 3 inhibited PI3K activity and induced apoptosis. Collectively, our study identified promising new platinum(II) derivatives such as complex 3, paving the way for future in vitro and in vivo validations and safety studies
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