A rare presentation of Retiform Hemangioendothelioma in sacral area

Retiform Hemangioendothelioma is an extremely rare tumor. It was first explained by Calonje et al in 1994. It is a vascular neoplasm of borderline malignancy, mostly seen in young age, and extremities. A 65 years old female patient presented with a recurrent growth in the sacral region, along with skin ulceration. FNAC revealed a cystic lesion with inflammation. Previous biopsy showed granulation tissue only. The growth was surgically removed for the third time and sent to Histopathology lab. Gross examination revealed a partial skin covered tissue mass of 15x10x3 cm. Cut section showed solid cystic growth of 2x2x1.5 cm. Microscopically, proliferating neoplastic elements, vascular in nature, in a net like pattern seen. Monomorphic cells with scant cytoplasm with hobnail nuclei lined the vessels. Scant mitotic figures, lymphocytic infiltration, and focal fibrocollagenous material were seen. Dermis was focally involved. On immunohistochemistry, Ki-67 (low proliferation) and CD 34 were positive. Hence the diagnosis of Retiform Hemangioendothelioma was made

Effect of α and β Phase Volume Fraction on Machining Characteristics of Titanium Alloy Ti6Al4V

AbstractMicrostructure of titanium alloys has great influence on the manufacturing processes. In the current investigation the effect of change in volume fraction of alpha and transformed beta phase in the bimodal titanium alloy Ti6Al4V was discussed in relation with the mechanical and machining performance. The quenching process in STA (solution treatment and annealing) heat treatment was delayed by 30, 50 and 70 sec to get different microstructural morphology in each heat treated specimen. Face turning experiments with dry and high pressure coolant environment were performed on the solution treated samples. A detailed chip mechanism and microstructural analysis was performed to investigate the role of quench delay and subsequent change in phase volume fraction on thermal softening and frictional phenomenon in machining. The specimen treated with quench delay of 50 sec exhibited poor machinability because of thermal and frictional shock generated at the cutting zone

PARAMETRIC OPTIMIZATION FOR IMPROVED SURFACE FINISH IN CNC TURNING OPERATION

The parameters affecting the roughness of surfaces produced in the turning process for various materials have been studied by many researchers. Design of experimentswere conducted for the analysis of the influence of the turning parameters such as cutting speed, feed rate and depth of cut on the surface roughness.This paper presents a novel approach for the optimization of machining parameters on turning of thetool work piece combination of the Raw material HCHCr with cemented carbide and CBN tool. The parameters –Speed, Feed and Depth of cut to be maintained for HCHCr weredetermined in terms of optional values or levels for the tool. Historic data wasreferred from the records of the company to understand the effect of introducing variation in the input to realize a given output as a ‘Response’ for surface finish. Statistical data analyzed using ANOVA, DOE and Regression to identify the given machining parameters for the operation. Experimental run conducted for validating the values realized through this Analytical treatment of the data.Experimental outcomes have proved that theresponses in turning process can be enhanced efficiently through this freshapproac

Parametric Optimization for Improved Surface Finish in Cnc Turning Operation

The parameters affecting the roughness of surfaces produced in the turning process for various materials have been studied by many researchers. Design of experimentswere conducted for the analysis of the influence of the turning parameters such as cutting speed, feed rate and depth of cut on the surface roughness.This paper presents a novel approach for the optimization of machining parameters on turning of thetool work piece combination of the Raw material HCHCr with cemented carbide and CBN tool. The parameters –Speed, Feed and Depth of cut to be maintained for HCHCr weredetermined in terms of optional values or levels for the tool. Historic data wasreferred from the records of the company to understand the effect of introducing variation in the input to realize a given output as a ‘Response' for surface finish. Statistical data analyzed using ANOVA, DOE and Regression to identify the given machining parameters for the operation. Experimental run conducted for validating the values realized through this Analytical treatment of the data.Experimental outcomes have proved that theresponses in turning process can be enhanced efficiently through this freshapproac

Synthesis and characterization of indium-doped ZnO nanoparticles by coprecipitation method for highly photo-responsive UV light sensors

In this investigation, we employed a cost-efficient co-precipitation technique to synthesize nanostructures of Indium-doped ZnO, incorporating varying percentages of Indium (0.25 %, 0.5 %, 1 %, 2 %, and 4 %) into the ZnO lattice. These Indium atoms were introduced either by replacing oxygen (O2) or occupying tetrahedral interstitial spaces within the structure. The resultant materials exhibited an average crystal size ranging from approximately 5 to 10 nm and displayed a highly crystalline nature. The UV–visible spectroscopy of these synthesized materials, revealing an excitation spectrum spanning 380 nm–395 nm. Photoluminescence measurements showed two distinct emission peaks at 390 nm and 471 nm, originates from the recombination of the free excitons through an exciton-exciton collision process and the presence of defects or impurities in the In–ZnO nanostructures. Defects in the crystal lattice, such as oxygen vacancies or interstitial defects, can create energy levels within the bandgap. Subsequently, we evaluated the suitability of these Indium-doped ZnO nanostructures for light sensor applications. Response and recovery times to infrared (IR), visible, and ultraviolet (UV) light was recorded. Remarkably, the nanostructures exhibited exceptional response and recovery times, in UV light compared to their performance with IR and visible light. This significant performance of synthesized materials in UV light shows the cost-effective co-precipitation method in fabricating Indium-doped ZnO nanostructures for UV light sensing applications

Electronic Structure of Visible Light-Driven Photocatalyst δ‑Bi₁₁VO₁₉ Nanoparticles Synthesized by Thermal Plasma

Size confinement for tailoring of electronic structures can in principle be explored for enhancement of photocatalytic properties. In the present work, vanadium-doped bismuth oxide nanoparticles, with an average particle size of 36 nm, are synthesized for the first time, using the thermal plasma method, in large scale with high yield to explore for photocatalytic applications. The electronic and crystallographic structures of the sample are studied experimentally and theoretically. Systematic investigations of the electronic structure of the fluorite type cubic phase of Bi₁₁VO₁₉ nanoparticles are reported for the first time. Enhancement is observed in the photocatalytic activity as compared to other delta phases of bismuth vanadate. The valence band is found to comprise mainly of O 2p states, whereas the conduction band arises from V 3d states giving rise to a band gap value of 2.26 eV. Absence of excess O in δ-Bi₂O₃ results in shrinking of the band gap because of O 2p, Bi 6s and 6p states from the surrounding atoms at doping sites. Bi₁₁VO₁₉ nanoparticles show an efficient visible light absorption and exhibit excellent photodegradation properties of methylene blue solution under visible light irradiation