Nanoengineered Materials for SWIR HOT Detectors

Heavy metal Selenide has been investigated for more than half century for high operating temperature (HOT) mid wave infrared (MWIR) applications. Most of the efforts have been devoted to make detector arrays on high-resistivity Si substrates for operating wavelengths in the 1.5 to 5.0 m region using physical vapor transport grown poly crystalline materials. For most of the biological spectral and imaging applications, short wave infrared (SWIR) detectors have shown better performance. Recent growth materials have shown variation in morphology with slight change in growth conditions and hence variation in performance parameters such as bandgap, mobility and resistivity from sample to sample. We have performed growth and optical characterization of pure and doped PbS and PbSe and have determined bandgap using available theoretical models for different morphologies

Design of Materials for IR Detectors Using High Z Elements for High Energy Radiation Environment

There is a strong need for rad hard and high operating temperature IR detectors for space environment. Heavy metal Selenides (high Z and large density) have been investigated for more than half century for high operating temperature mid wave infrared (MWIR) applications. Most of the efforts have been devoted to make detector arrays on high-resistivity Si substrates for operating wavelengths in the 1.5 to 5.0 m region using physical vapor transport grown poly crystalline materials. For most of the biological spectral and imaging applications, short wave infrared (SWIR) detectors have shown better performance. Recent growth materials have shown variation in morphology with slight change in growth conditions and hence variation in performance parameters such as bandgap, mobility and resistivity from sample to sample. We have performed growth and optical characterization of binary materials CdSe-PbSe to determine the suitability for IR detector. We have determined bandgap using several theoretical models for different morphologies observed during growth on silicon wafers

Autopsy report of disseminated histoplasmosis: An important differential of adrenal enlargement

A 57-year-old diabetic male, presented with altered sensorium since 2 days. He had a history of weight loss, loss of appetite, intermittent low-grade fever of 6 months duration. He had been administered empirical antituberculous therapy some months ago with no alleviation of symptoms. On examination, he was asthenic, normotensive, and anemic with hepatosplenomegaly. Ultra-sonography abdomen revealed bilateral enlarged adrenals with hepatosplenomegaly. Clinically impression was of tuberculosis disseminated malignancy. He expired within 2 days of admission. At autopsy, both the adrenals were markedly enlarged showing extensive areas of necrosis on the cut surface. Histology showed them to be brimming with colonies of yeast-forms of Histoplasma capsulatum. These organisms were also seen in the spleen, lungs and kidneys. The patient had died of septicemia following disseminated histoplasmosis that was, unfortunately, not diagnosed during his life. Histoplasmosis is amenable to treatment with Amphotericin B. Prompt diagnosis and treatment could have helped in salvaging this patient

Importance of combined approach of investigations for detection of asymptomatic Hashimoto Thyroiditis in early stage

INTRODUCTION: Hashimoto’s thyroiditis (HT) is the most common cause of goitrous hypothyroidism in iodine sufficient areas. The diagnosis of HT is important because it progresses to hypothyroidism, and also, it is associated with thyroid lymphoma and papillary thyroid carcinoma. Apart from thyroid antibodies, assessment of thyroid function test (TFT) levels, ultrasonography (USG), and cytological analysis can help in early diagnosis and management of HT. AIMS AND OBJECTIVES OF THIS STUDY: To know the age incidence and clinical presentation of HT, its association with thyroid hormone levels and with thyroid antibodies and its correlation with the cytologic grade of HT. MATERIALS AND METHODS: Consecutive convenient method of sampling was adopted at the cytology clinic. Fine-needle aspiration cytology of patients presenting with thyroid enlargement was done using standard technique and aseptic precautions. RESULTS: Out of 875 cases of thyroid cytology, 134 cases were diagnosed as HT over a 4-year period. A strong female preponderance was observed. A significant proportion of them (103/134) presented in the first four decades of life. Majority of cases (60.63%) were hypothyroid, while 15.74% were hyperthyroid and 23.62% were euthyroid. Apart from thyroid enlargement, although a majority of patients presented with symptoms related to the thyroid, a significant number of patients (38.80%) were asymptomatic. Conclusions: A combined approach of cytological grading of HT along with USG, TFT levels, and thyroid antibodies can detect hypothyroid and subclinical hypothyroid or euthyroid state of HT and provide an appropriate guide to therapy

Solid-pseudopapillary tumor of pancreas in a male child: A nuclear feature at light microscopy that can aid in its diagnosis in cases where papillary architecture is not very apparent

Solid-pseudopapillary tumor (SPPT) of the pancreas is an uncommon low-grade exocrine pancreatic malignancy. An 11-year-old male child presented with pain in the abdomen. He had a history of fall 1-week back for which a computerized tomography (CT) scan was advised. A pancreatic mass was incidentally detected on CT scan and diagnosed as pancreatic pseudocyst. Explorative surgery was performed that revealed a solid-cystic tumor in the tail of the pancreas. The histopathological examination reported the features of pancreatic SPPT which was also the final diagnosis