Publications by authors named "Kumbhakarna N"

Over the last several decades, saturated polycyclic cage compounds have remained a point of interest for organic chemists because of their unique characteristics and reactivity. For the first time, a detailed analysis of the synthesis, properties and transformations of 1,3-bishomocubanes, which fall under the rare category of chiral cage compounds, is provided in this article. This review which also includes the authors' work in this area over the last decade is expected to serve as a valuable resource for chemists interested in the fascinating chemistry and properties of polycyclic cage compounds.

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The present work reports synthesis, characterization and theoretical insights on novel hydroxymethyl-bishomocubanone derivatives. Twelve new bishomocubanes (BHCs) were synthesized and fully characterized by various spectroscopic techniques and single crystal X-ray analysis. The densities of the title compounds were in the range of 1.

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Novel 1,4-disubstituted cubane derivatives have been designed and selected ones have been successfully synthesized and characterized by various analytical and spectroscopic techniques, including single-crystal X-ray analysis. A detailed computational study at B3LYP/6-311++G(d,p) level of theory revealed that all newly designed 1,4-disubstituted cubane derivatives possess higher densities, higher density-specific impulse and superior ballistic properties when compared to conventional fuels, for example, RP-1. These compounds also exhibit acceptable kinetic and thermodynamic stabilities which were evaluated in terms of their HOMO-LUMO energy gap and bond dissociation energies, respectively, and are superior to TEX and many other compounds containing explosophoric groups.

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The accurate measurement of temperature in sooty flames remains a challenging task. In this study, the procedure for calibration and use of a consumer-grade digital single-lens reflex (DSLR) camera for the measurement of temperature in sooty flames using color-ratio pyrometry (CRP) is elucidated. Owing to the necessity of acquiring RAW images for CRP, investigations conducted thus far have been limited to stable flames.

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This work provides new insights for the liquid-phase decomposition of bis(triaminoguanidinium) azotetrazolate (TAGzT). The liquid-phase decomposition process was investigated using a combined experimental and computational approach. Sub-milligram samples of TAGzT were heated at rates of about 2000 K s-1 to a set temperature (230 to 260 °C) where liquid-phase decomposition occurred under isothermal conditions.

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Nasal natural killer/T cell lymphomas are locally destructive mid-facial necrotizing lesions. It is an uncommon disease but, usually shows a highly aggressive clinical course. Amongst the sino-nasal lymphomas, it is the most common type.

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Hemophagocytic syndrome is a life threatening condition characterized by uncontrolled hyperinflammation on the basis of various inherited or acquired immune deficiencies. We report a case of hemophagocytic syndrome in a 18 years old male with a brief review of literature.

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Pure mucinous carcinoma of the male breast is an uncommon malignant breast neoplasm and extremely rare is its metastasis in axillary lymph nodes. Most of these cases have been diagnosed after surgical resection with only a few cases diagnosed on fine needle aspiration cytology (FNAC). Although FNAC is well established in the evaluation of breast masses in females there are few reports in males.

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FNAC of soft tissue tumours was done in 67 patients. The findings were compared with histopathologic findings. Overall diagnostic accuracy was 93.

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Ginseng (Panax ginseng) and Ashwagandha (Withania somnifera) are widely used as geriatric tonics. Both individually have not shown any toxicity on long term administration. Study was planned to assess the safety of the combination by doing subacute toxicity study in rats with 90 days oral administration using three doses.

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Congenital plexiform neurofibroma is regarded as pathognomonic of neurofibromatosis (NF) especially when it is large and involves a major nerve trunk with changes of elephantiasis neuromatosa. Only very rarely malignant changes have been reported in cases who have NF for less than 5 years. 'Borderline' lesions are seen especially in patients with NF.

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A male child aged six years presented with a swelling in neck and hypertension. He was diagnosed to have and operated for Carotid body paraganglioma with Coexistent pheochromocytoma. Hypertension persisted even after excision of both the tumours which could be controlled with anti-hypertensive agents.

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