Spark erosion behavior in the machining of MoSi2-SiC ceramic composites for improving dimensional accuracy.

The novel applications of MoSi2 and SiC as matrix and reinforcing materials in the creation of high-performance composites were investigated in this work. In particular, Spark Erosion Machining's geometric tolerances were studied in order to shed light on the technique's potential for precision manufacture in the realm of MoSi2-SiC composites. Our research focused on evaluating critical parameters and their impact on machining performance, including material removal rate, surface roughness, wear rate and drilled hole accuracy. In-depth research revealed the critical input factors that had the greatest impact on the machining procedure. Notably, parameters such as current (32%), sparking on time (23%), sparking gap voltage (12%), dielectric pressure (12%), and sparking off time (17%) emerged as the most influential factors, as determined by ANOVA analysis. These findings provide valuable insights into optimizing the Sparking EDM approach for MoSi2-SiC composite materials. This study further demonstrated the improvement in composite desirability ratings across multiple performance criteria, highlighting the effectiveness of Sparking EDM in enhancing machining outcomes (e.g., from 0.8523 to 0.9527). Correlations between the EDM's output responses were found to be quite high when geometric tolerances and the coefficient of determination (R2) were used (0.7858, 0.9625, 0.8427, 0.8678, 0.8474, 0.8368, 0.8344, 0.8671). Consider that, for the sake of a more complete understanding of the procedure's approach, the emphasis is on the methodology rather than the multifaceted metal removal mechanisms involved. This research doesn't dive further into the physical concerns of Spark Erosion Machining, but it does provide insights into the practical application of this technique in the precision manufacturing of MoSi2-SiC composite materials. For real-world medical applications such implanted devices, dental implants, surgical instruments, biological sensors and diagnostics, this study provides a valuable and encouraging approach. A validation experiment verifies the results, proving the feasibility of improved spark erosion in high-precision production. The results of this research show that EDM methods can be fine-tuned to produce ceramic composites with much greater MRR, superior surface finishes and a marked decrease in subsurface cracking and microstructural modifications. This is essential for protecting the integrity of materials used in life-saving medical equipment.

Si3N4-TiN rotary EDM optimization by Mo-Jaya algorithm with Pareto optimal solution, analysis of micro-structural and geometrical tolerances.

Research into rotary electrical discharge machining on high temperature with biomedical application Si3N4-TiN ceramic composite is presented in this paper. Current (I), pulse on time (Ton), pulse off time (Toff), dielectric pressure (DP), speed and spark gap voltage (Sv) are some of the many performance characteristics. Among the factors taken into account is the material removal rate, surface roughness, electrode wear rate, cylindricity, perpendicularity, top radial overcut, bottom radial over cut and run out. Multiple parameter combinations were validated experimentally and the resulting reactions were examined. Mean effects analysis and regression analysis are used to investigate the impacts of individual parameters. To comprehend the instantaneous behavior of the replies, multi-objective Jaya optimization is utilized to optimize the responses simultaneously. The multi-objective problem's outcomes are shown in 3D charts, with each showing the Pareto optimal solution. From this real conclusion, the optimal combinations of answers are extracted and reported. The aggregate optimization result was also shown, which factored in all eight responses. MRR of 0.238 g/min was obtained which is a 10.6% improvement from the experimental values. Electrode wear of 0.0028 g/min was obtained showing a 6.6% reduction. Similarly reduction in values of Surface roughness, top radial overcut and bottom radial over cut, Circularity, Perpendicularity, run out was observed and the percentages are 3.4, 4.7, 4.5, 7.8, 10.0 and 10.53 respectively. Details on the structural and morphological examinations of the various surface abnormalities that occur during the process have been presented.

A rare case of type-I auto-immune hepatitis and thyroiditis presenting with crescentic glomerulonephritis.

A middle-aged female patient with a past history of non-alcoholic liver disease and hypothyroidism presented with swelling of the body, off and on, for six months and rapidly worsening renal function. Renal biopsy showed crescentic glomerulonephritis with negative immunofluorescence. Serological tests were positive for anti-thyroglobulin, anti-nuclear antibody (1:80), p-anti-neutrophil cytoplasmic antibodies; gamma globulin was 5.23 g/dL and viral markers were negative. The patient was diagnosed to have autoimmune hepatitis type-1 and treated with injection methylprednisolone pulse (500 mg/day for 3 days) and maintained on oral steroids and azathioprine 100 mg. She responded dramatically to this treatment and has remained in complete remission at last follow-up.

Analysis of case series of milky urine: A single center and departmental clinical experience with emphasis on management perspectives: A prospective observational study.

BACKGROUND: Milky urine can be due to chyluria or lipiduria due to nephrotic syndrome. Filarial chyluria usually responds to medical management while non-filarial cases may require surgical intervention. AIM: To perform a prospective observational study in patients presenting with milky urine in our centre over a period of one year from July 2011 to June 2012, a complete biochemical work up and imaging to find out the site of leakage of lymph if it is a case of chyluria, its response to medical management and the requirement of surgical intervention. MATERIALS AND METHODS: Routine blood and urine investigations, 24 hour urine protein excretion, USG abdomen, serum lipid profile and rapid filarial antigen test were done in all. MRI abdomen was done in affordable patients. Renal biopsy was done in some chyluria patients for academic purpose and in milky urine with negative urine ether test. Sclerotherapy was done with 50% dextrose and 0.2% povidone iodine. Patients were followed up with 24 hour urine protein and triglyceride estimation. RESULTS: 18 cases of milky urine were encountered. 8 were filarial chyluria, 9 non- filarial and 1 MCD. Mean urine TG level and median 24 hour urinary protein excretion were 37.2 ± 24.6 mg% and 4.96 g respectively. The mean age for filariasis (22.9 ± 4.5 years) was significantly different from that of non-filarial etiology (31.5 ± 4.8 years) (P = 0.005). The mean 24 hour urinary protein for normal MRI cases (4.64 ± 0.70 g) was significantly different from those with dilated lymphatics (8.15 ± 2.55 g) (P = 0.02). All the non- filarial and 4 filarial cases required sclerotherapy. One patient required a second sitting. CONCLUSION: Milky urine is most commonly due to chyluria and occasionally due to nephrotic syndrome. Nephrotic syndrome is managed in its own way while chyluria not amenable to pharmacological intervention is managed with sclerotherapy.

A Rare Case of Type I RenalTubular Acidosis with Membranous Nephropathy Presenting as Hypokalemic Paralysis.

Type 1 renal tubular acidosis (RTA), or distal RTA (dRTA), is a disorder of renal tubular acidification, which is generally asymptomatic but may rarely present as hypokalemic paralysis. Here, we report the case of a young male who presented with sudden onset weakness of all 4 limbs and a 2-month history of swelling of the legs. An investigation revealed hypokalemia, metabolic acidosis, and nephrotic syndrome. Additional analyses revealed normal anion gap metabolic acidosis with a positive urine anion gap and dRTA. Renal biopsy showed evidence of membranous nephropathy (MN). The patient's weakness improved with potassium supplements. Normalization of the serum potassium level and disappearance of proteinuria were established with an ACE inhibitor and potassium supplementation. This case is an unusual combination of dRTA with MN coupled with the rare presenting symptoms of hypokalemic paralysis and medullary nephrocalcinosis.

Filariasis, with chyluria and nephrotic range proteinuria.

28 yr female presented with (grade III) chyluria, with nephrotic range proteinuria and Ig M mesangial deposition in immunofluorescence, secondary to filariasis which was confirmed by serology and microfilaria in glomerulus,and successfully treated by Renal Pelvic instillation sclerotherapy with 0.2% povidine and medical treatment (Diethylcarbamazine). She was asymptomatic with follow up period of 19 months.