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The theme of this study is to investigate the theoretical and numerical simulation of heat and mass transfer of magneto hydrodynamic power-law nanofluid flow over a stretching sheet with surface heat flux and Soret/Dufour effects. The mass flux and energy flux increase with temperature and concentration differences using the Soret/Dufour impact. The similarity transformations were used to transform a physical problem into a non-linear differential equation, and the non-linear equations were solved by the Keller box technique. The Soret/Dufour and magnetic field are incorporated into a nanofluid model. The similarity transformation was used to reduce thermal energy, mass, and momentum in algebraic systems. The impact of nanofluid factors, such as generalized Brownian motion parameter Nb, Dufour parameter Df, Soret parameter Sr, Le, and Pr, are generalized Lewis and Prandtl numbers; the thermophoresis parameter Nt and magnetic parameter on dimensionless stretching surface functions are shown numerically and graphically. The quantitative relationship between heat transfer and skin friction is shown by using Keller box and MATLAB. The skin friction coefficient Cf, Sherwood number Shx, and Nusselt number Nux values were also computed and displayed on the graph. The increment in slip temperature, fluid velocity, and fluid concentration is enhanced with a high Dufour parameter. The temperature variation and fluid concentration are decreased with applied-magnetic effects because the magnetic field acts like an insulating material in heat transfer systems. The enhancement in the Nusselt number and Sherwood number is increased with Soret and Dufour effects. [ABSTRACT FROM AUTHOR]

In the present investigation, zirconium dioxide (ZrO2) and zirconium diboride (ZrB2) have been used in the development of an aluminum-based composite. A microwave sintering technique was employed for the processing of the composite. The aluminum-based composite was developed with the constant 5 wt.% of ZrO2. The weight percent of ZrB2 increased from 2.5% to 7.5%. Uniform distribution of the reinforcement particles was observed for the composition Al–5 wt.% ZrO2–2.5 wt.% ZrB2 composite and Al–5 wt.% ZrO2–5 wt.% ZrB2 composite. The relative density of Al–5 wt.% ZrO2–5 wt.% ZrB2 composite was found to be 0.9874. The percent porosity of the Al–5 wt.% ZrO2–5 wt.% ZrB2 was 1.259%. Results showed that hardness, compressive strength, % tensile strength, and fatigue strength (at 1 × 107 cycles) were improved by about 74.28%, 18.18%, 58.77%, and 60.77%, respectively. XRD of the Al/ZrO2/ZrB2 composite showed the presence of Al, ZrO2, ZrB2, MgAl2O4, and Al2Cu phases. The number of grains per square inch for composition Al–5 wt.% ZrO2–5 wt.% ZrB2 composite was found to be 989.11. This result showed that a finer grain structure has been obtained after the solidification of Al–5 wt.% ZrO2–5 wt.% ZrB2 composite. The fracture surface of the Al–5 wt.% ZrO2–5 wt.% ZrB2 composite was composed of a dendrite structure with micro-porosities. Dimples were also not observed from the tensile fracture surface morphology of the composite. [ABSTRACT FROM AUTHOR]

Objective: To investigate the dependency on feeding gastrostomy tubes in patients with head and neck cancers treated with radiotherapy alone or concurrent chemo-radiotherapy. Study Design: Retrospective longitudinal study. Place and Duration of Study: Combined Military Hospital, Rawalpindi and Shaukat Khanum Hospital, Peshawar Pakistan, from Jan and Jul 2022. Methodology: A total of 115 patients with head and neck cancers having no baseline dysphagia and having gastrostomy tubes were included. All had received an equivalent of 60 greys in 30 fractions or more of radiotherapy. Their swallowing was evaluated weekly during radiotherapy and then every 4-6 weeks on post-treatment follow-up. The total time duration of patient dependency on feeding gastrostomy tube after treatment completion was noted for each head and neck cancer subsite. Results: Of a total of 115 patients, 49(43%) of the patients had nasopharyngeal cancers, 22(19%) had laryngeal, 29(24%) oral cavity, 7(6%) hypopharyngeal and 9(8%) had cervical esophageal cancers. Proportion retaining gastrostomy tube for more than six months of treatment was 8.7% (median duration of retention was five months) with hypopharyngeal, nasopharyngeal, oral cavity, and laryngeal cancer were 14%, 9%, 9% and 5%, respectively. Conclusion: The proportion of patients with head and neck cancers requiring more than six months of a gastrostomy tube is 5-14%. Baseline assessment of swallowing and nutrition and prophylactic feeding gastrostomy can avoid treatment interruptions. Longer duration of retention of a gastrostomy tube is associated with poor quality of life in head and neck cancer patients receiving radiation or concurrent chemo-radiation. [ABSTRACT FROM AUTHOR]

PVC nanocomposite (NC) films with cubic CeO 2 and Ni-doped CeO 2 (NDC) have been prepared using a conventional solution-casting technique. The prepared films were characterized with FT-IR spectrometer, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The optical and thermal properties of the films were evaluated using a UV-visible spectrophotometer and TGA/DSC. The optical study revealed a decrease in optical band gap energies (4.19 to 4.06 eV) whereas the increase in other optical constraints such as optical conductivity, Urbach energy, dispersion energy, refractive index, and dielectric constant of PVC NCs than pristine PVC was observed. The XRD patterns showed the presence of cubic crystalline NDC with a relatively narrower principal diffraction peak in the PVC matrix and the nonexistence of unexpected vibrational peaks in the FTIR spectra of PVC NCs confirmed the successful incorporation of nanostructured CeO 2 and NDC into PVC. Thermogravimetric analysis showed the higher thermal stability of NDC/PVC NC than PVC whereas differential scanning calorimetry declared no significant change in the glass transition temperature (T g ) of the NCs. Moreover, a good dispersion of Ni-doped CeO 2 nanofiller was noticed in scanning electron micrographs., (© 2024 Wiley Periodicals LLC.)