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Ahmed Mahrous,1 Ebaa Alagha,1 Tariq Almutairi,2 Fahad Albishi,2 Ibrahim Alfayomi,3 Nawaf Rasheed3 1Restorative Department, Vision Colleges, Jeddah, Saudi Arabia; 2Internship Program, Vision Colleges, Jeddah, Saudi Arabia; 3Faculty of Engineering, King Abdul-Aziz University, Jeddah, Saudi ArabiaCorrespondence: Ebaa Alagha Email drebaaialagha@gmail.comPurpose: This study analyzed the stress distribution of restored principal abutments in free-end saddle partial dentures.Materials and Methods: The mandibular second premolar was modeled with class II cavity restored with composite resins (Tetric N Ceram and Charisma Smile). Finite element analysis (FEA) was used to examine the stresses under 200-N static load vertically and horizontally and the results were graphically illustrated in the form of von Mises stresses.Results: The von Mises stress distribution patterns of two different composite resins (Tetric N Ceram and Charisma Smile) were very similar in all modes of loading.Conclusion: Composite resins with a similar modulus of elasticity in class II cavities with occlusal rest seat preparation had similar stress distributions.Clinical Significance: Nanohybrid composite resin restorations may be a possible method for preparing abutments for receiving elements of the removable partial denture (RPD).Keywords: composite resin, finite element analysis, rest seat, RPD

A newly synthesis composite thin films of poly(vinyl chloride) has been refinement with ionic liquid, where PVC dissolved in THF with various concentrations of IL by casting method to form the composite thin films, without any reaction and IL dangles within PVC matrix. The thin films were examined by the diffusive reflectance device under the wavelength range (238–1300 nm). The XRD, EDX, and AFM techniques were utilized to discover the structure of the PVC matrix after additive IL. The XRD analysis illustrated the amorphous structure of the films, while the EDS analysis illustrated the main composition of pure PVC and composite PVC/IL. The optical properties and optical parameters were studied. The reflectance, extinction factor, transmittance, and imaginary dielectric constant declined, the absorption value was between (80–89 %), and the refractive index, real dielectric constant, and optical conductivity were increased. The indirect energy gap declined from 4.2 eV to 2.2 eV and the direct energy gap declined from 3.7 eV to 2.6 eV. The Urbach energy was increased from 2.09 eV to 15.45 eV revealing an increase in the disorders of electrons. The Ed increased from 23.42 eV to 70.68 eV and Eo increased from 7.00 eV to 10.88 eV. AFM analysis illustrated the roughness of the films increased after additive IL to the PVC Matrix from 1.08 nm to 4.45 nm and the root mean square of the particles ranged from 1.57 nm to 5.56 nm. The PVC composite thin films are utilized in solar cell and sodium-ion battery applications. [ABSTRACT FROM AUTHOR]

The consequential effects of heavy metal consumption by man suggest the need for plant assessment for bio-concentration and translocation potentials. This study aimed at comparing the potential of dent maize with sweet maize for phytoremediation of Chromium (Cr) and Nickel (Ni) contaminated soils. Soil samples were taken randomly to a depth of 20 cm. Out of the samples taken; about 500 g of the samples were homogenized, dried, sieved, and used for the determination of soil physicochemical properties. The remaining soil samples were used to fill the polythene bags for the plant growth. The experimental design used was 22 by 2 general factorial design consisting of 4 treatments (1 g/dm3 of Ni (NO3)2.6H2O; 3 g/dm3 of Ni (NO3)2.6H2O; 1 g/dm3 of Cr (NO3)2.9H2O and 3 g/dm3 of Cr (NO3)2.9H2O), 2 replicates of each and the control. The setup was made for each of the maize types. Three seeds of maize were planted on each of the soil samples at a depth of 4 cm and the setup was properly monitored. Soil samples were analyzed at day 1 and every 14 days interval in a period of 70 days after planting (DAP). The result of the initial analysis of the soil samples indicates that the control soil sample contained 0.17+0.002 mg/kg of Cr and 0.03+0.001 mg/kg of Ni for soil seeded with both the dent and sweet maize. The mean concentration of Cr and Ni from the soil samples taken from soil contaminated with 1g treatment were 1.24+0.001 mg/kg and 1.43+0.002 mg/kg respectively, while that contaminated with 3g treatment has 3.98+0.02 mg/kg of Cr and 2.96+0.02 mg/kg of Ni. The results also show a reduction in the heavy metal concentrations of the soil through the 70 days of planting. The Cr and Ni contents of the two maize types increase with the increase in the amount of metals (3 g > 1 g> control) in the soils in which they were seeded. Though, the two types of maize are good phytoplant, sweet maize is more active in Cr removal than dent maize. The two maize types are better in bioaccumulation than in translocation. The growth of the plants was not retarded by the presence of the metal which shows their tolerance and effectiveness in remediating Cr and Ni contaminated soil. The use of this technology will help in attaining sustainable development goals as it addresses the problem of environmental degradation while the subsistence agriculture will be promoted and hence poverty will also be alleviated or eradicated.

Poly (vinyl chloride) (PVC) films modified with ethylenediamine (en) and doped by nanoparticles (TiO2, ZnO, NiO, and MgO). A mixture of 0.5 g PVC/en dissolved in THF and 0.01 wt % of nanoparticles were used in doping PVC to produce the nanocomposite films. All modified PVC films were characterized by different analysis techniques such as Fourier Transform Infrared (FTIR), Nuclear Magnetic Resonance Spectrometer (NMR), diffusive reflectance spectroscopy (DRS), X‐ray diffraction analysis (XRD), and scanning electron microscopy (SEM). The DRS was used to analyse the scattered IR energy of the samples at wavelengths between (250–1350 nm). The optical properties and oscillator strength were also studied, the transmittance and reflectance values declined for the PVC films, and the absorption coefficient was observed between (79–89 %). The direct energy gap decreased from 4.6 to 1.9, and the indirect energy gap reduced from 4.3 to 1.9. The XRD exhibited a semi‐crystalline structure and the SEM test exhibited a porous structure of all samples. The Urbach energy was increased from 0.8772 eV to 14.712 eV, single oscillator energy (Eo ${{E}_{o}}$) was also increased from 6.38 eV to 13.69 eV and the dispersion energy (Ed) ${{(E}_{d})}$ increased from 23.40 eV to 70.63 eV. Moreover, the surface roughness parameters Ra and Rq of the PVC films in modified and doping were increased from 3.86 nm to 8.14 nm, and 5.08 nm to 10.10 nm respectively. So, PVC results show increased optical properties after modification with en and doping by NPs are used in the light conversion and aerospace industries. [ABSTRACT FROM AUTHOR]

This study was conducted to measure a group of hormones related with infected individuals with the shortage of the growth hormone by studying 150 patients in comparison with 50 samples taken from normal individuals as a control group. The study included investigation GH gene via polymerase chain reaction technology (PCR) by two primers designed specifically for this study (GH3, GH4). The results showed that mutations occurred in 12 individuals from the samples, 8% for GH3 , whereas the GH4 showed no absence or disorder in the sequence of bases. The results of Sequencing using the Blast program showed appearance of many mutations of deletion mutations and insertion mutations , and substitution mutations of two types of transition and transversion. The concentration of hormones has been measured were human Testosterone hormone , Prolactin hormone ,Cortisol hormone ,The results showed a highly significant differences in the levels of the averages of hormonal analysis , as well as a significant decrease in the average length of individuals and high moral appeared in body mass index(BMI) under the moral under the moral level of P ≤ 0.05.

Promote the conductivity of the nanocomposite thin films Co3O4:Cr2O3/C to produce a spectroscopic selective surface with high performance to absorb solar light. The nanocomposite coating Co3O4:Cr2O3/C has been fabricated by a spin coating method and casting method. Different concentrations of nanoparticles (Co3O4:Cr2O3) were immersed in the carbon ash (C) to comprise the economic nanocoating. The XRD test of the patterns has been carried out for all the specimens to prove the crystalline structure of nanocomposite thin films. The nanocomposite thin film Co3O4:Cr2O3/C has been tested at a frequency range between 375 kHz and 1.5 MHz, and the electrical properties of the thin films have been investigated for real and imaginary of the dielectric constant, conductivity, volume with surface energies of losses, and loss factor. The content of carbon (C) in the nanocomposite Co3O4:Cr2O3/C is fixed ratio (7% wt.), but the concentration of Co3O4 has various ratios (0.5, 1, 1.5, 2, and 2.5% wt.), and Cr2O3 has several ratios (2.5, 2, 1.5, 1, and 0.5% wt.), that have the symbols F, G, H, I, and K. These nanoparticles exhibited a worthy improvement in the structure of carbon ash, thereby, the XRD inspection of topography confirm the nanocomposite Co3O4:Cr2O3/C thin films have a crystalline structure. Generally, the results have demonstrated that these nanocomposite Co3O4:Cr2O3/C thin films have good conductivity. Therefore, thin films of nanocomposite can use in photovoltaics, solar cell, and coating over a flat plate collector owing to their properties as the high absorption to light. [ABSTRACT FROM AUTHOR]