The present paper explores the stability and failure response of elastoplastic Ni/Al2O3 functionally graded plate under thermomechanical load using non-linear finite element formulation based on first-order shear deformation theory and von-Karman's nonlinear kinematics. The temperature dependent thermoelastic material properties of FGM plate are varied in the thickness direction by controlling the volume fraction of the constituent materials (i.e., ceramic and metal) with a power law, and Mori-Tanaka homogenization scheme is applied to evaluate the properties at a particular thickness coordinate of FGM plate. The elastoplastic behavior of FGM plate is assumed to follow J2-plasticity with isotropic hardening, wherein the ceramic phase is considered to be elastic whereas the metal is assumed to be elastic-plastic in accordance with the Tamura-Tomota-Ozawa model. Numerical studies are conducted to examine the effects of material and geometrical parameters, viz. material in-homogeneity, slenderness and aspect ratios on the elastoplastic bucking and postbuckling behavior and the failure response of FGM plate. It is revealed that material gradation affects the stability and failure behavior of FGM plate considerably. Furthermore, it is also concluded that FGM plate with elastic material properties exhibits only stable equilibrium path, whereas the elastoplastic FGM plate shows destabilizing response after the ultimate failure point.

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In this study, concrete was prepared by complete replacement of sand and partial replacement of cement by Fly-Ash using different admixtures like NaOH- Na2SiO3 solution, CaO- Na2SiO3 solution, CaO- Na2SiO3 gel and Micro Silica in order to evaluate the effects of these admixtures on properties of HVFA concrete. Solutions and Gel were prepared by mixing both materials in different ratios. It was noted down in mix proportions. The study included determination of compressive strength and flexural strength with (1) Variation in NaOH- Na2SiO3 solution (2) Variation in CaO- Na2SiO3 solution (3) Variation in CaO- Na2SiO3 gel (4) Variation Micro Silica percentages (5) Combination of above admixtures which gave better results. Durability tests like abrasion test and RCPT test were also conducted on HVFA concrete specimens. Test results indicated a decrease in compressive as well as flexural strength when admixture percentage increased. Use of NaOH- Na2SiO3 solution is not even useful in lower percentages. It shows lower compressive and flexural strength than strength of concrete when made without use of any admixture. It was also found out that CaO- Na2SiO3 solution imparted more compressive as well as flexural strength than CaO- Na2SiO3 gel. But increase in Na2SiO3 shows decreased compressive as well as flexural strength. However Micro Silica showed better result than other admixtures and combination of CaO- Na2SiO3 solution and Micro Silica gave higher compressive as well as flexural strength than individual admixture. Graphs showing the above variations are also plotted under this thesis document. After completion of the project it was concluded that HVFA concrete has adequate compressive and flexural strength. Apart from this the cost per cubic meter of HVFA concrete is comparable to that of the conventional concrete as cement was also partially replaced by Fly-Ash. So it can be used for the construction of non-reinforced elements. Further research needed for checking suitability of HVFA concrete for reinforced elements and paver material.

The present study is aimed to investigate the nonlinear transient response of an aluminum-zirconia functionally graded material (FGM) plate with a central circular hole under thermo-mechanical loadings. The nonlinear formulation is based on the first-order shear deformation plate theory along with geometric nonlinearity incorporated in the von Karman sense. The finite element numerical technique is employed to solve approximately the governing equations of motion derived through Hamilton's principle. A MATLAB program, developed to carry out the investigation, is verified for accuracy by comparing the results with those reported in the literature-under mechanical and thermo-mechanical loadings. Numerical results are presented to show the effect of various parameters, viz. material gradation exponent, geometric variables, hole size, and boundary conditions, on the nonlinear transient response of the FGM plate. It is found that the material gradation exponent has a noticeable effect on the transverse deflection of vibration of the FGM plate with a hole, but the frequency of vibration is not affected much. Further, with the increase in the size of hole in the FGM plate, the amplitude of its vibration decreases while the frequency of vibration increases.

Cryptococcal pulmonary nodule in an immunocompetent individual is rare. Here, we perform a literature review on management of asymptomatic pulmonary cryptococcus detected incidentally on radiological imaging. CASE PRESENTATION: An 80-year-old African American male with past medical history of stage II prostate cancer and hypertension presented to our hospital with subacute onset of bilateral lower limb weakness. Extensive workup was inconclusive for etiological diagnosis but showed an incidental 1.2 x 0.9 cm spiculated left upper lobe nodular density on CT chest. Biopsy of the lesion was performed to determine cause and to rule out paraneoplastic syndrome. Cytology was negative for malignant cells but, in fact showed localized granulomatous reaction with fungal forms consistent with Cryptococcus. Serum and CSF were negative for Cryptococcal antigen. He was HIV negative and had no respiratory symptoms. Treatment with fluconazole 400 mg once a day was initiated.

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