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Cadmium telluride (CdTe) high purity, bulk, crystal ingots doped with phosphorus were grown by the vertical Bridgman melt growth technique to understand and improve dopant solubility and activation. Large net carrier densities have been reproducibly obtained from as-grown ingots, indicating successful incorporation of dopants into the lattice. However, net carrier density values are orders of magnitude lower than the solubility of P in CdTe as reported in literature, 1018/cm3 to 1019/cm3 [J. H. Greenberg, J. Cryst. Growth 161, 1–11 (1996) and R. B. Hall and H. H. Woodbury, J. Appl. Phys. 39(12), 5361–5365 (1968)], despite comparable starting charge dopant densities. Growth conditions, such as melt stoichiometry and post growth cooling, are shown to have significant impacts on dopant solubility. This study demonstrates that a significant portion of the dopant becomes incorporated into second phase defects as compounds of cadmium and phosphorous, such as cadmium phosphide, which inhibits dopant incorporation into the lattice and limits maximum attainable net carrier density in bulk crystals. Here, we present an extensive study on the characteristics of these second phase defects in relation to their composition and formation kinetics while providing a pathway to minimize their formation and enhance solubility. [ABSTRACT FROM AUTHOR]

We applied time-resolved pump-probe spectroscopy based on free carrier absorption and light diffraction on a transient grating for direct measurements of the carrier lifetime and diffusion coefficient D in high-resistivity single crystal CdTe (codoped with In and Er). The bulk carrier lifetime τ decreased from 670 ± 50 ns to 60 ± 10 ns with increase of excess carrier density N from 1016 to 5 x 1018 cm-3 due to the excitation-dependent radiative recombination rate. In this N range, the carrier diffusion length dropped from 14 µm to 6 µm due to lifetime decrease. Modeling of in-depth (axial) and in-plane (lateral) carrier diffusion provided the value of surface recombination velocity S = 6 x 105 cm/s for the untreated surface. At even higher excitations, in the 1019-3 x 1020 cm-3 density range, D increase from 5 to 20 cm²/s due to carrier degeneracy was observed. [ABSTRACT FROM AUTHOR]

Foreign body (FB) ingestion is a common emergency managed by otorhinolaryngologists. The clinical manifestations and management vary as per the site of FB and its complications. The diagnosis of FB ingestion is often challenging and depends on its clinical presentations and imaging. One of the rare complications of FB ingestion is migration, which has the potential to result in morbidity and mortality. Migration of FB is said to have occurred in the presence of negative rigid esophagoscopy and positive radiography. Migration of FB to the neck requires neck exploration for its successful removal. Here, we report a case of sharp FB ingested, which penetrated through the hypopharyngeal wall by its sharp end and migrated into the deep space of the neck. [ABSTRACT FROM AUTHOR]

Aim: Mucormycosis is a rare but severe fungal infection, particularly found in immunocompromised patients. Currently this dreaded mucormycosis is rising among COVID-19 paediatric patients during their treatment period or after their discharge from hospital. It is also called as black fungus. The aim of this study is to evaluate the COVID-19 associated mucormycosis (CAM) in head and neck region of the paediatric patients with its clinical manifestations and management. Material and methods: This is a descriptive and prospective study of paediatric patients with COVID-19 associated mucormycosis (CAM) carried out at a postgraduate teaching hospital. This study was conducted between March 2020 to April 2021. Patient profile such as age, sex, comorbidities, clinical presentations, diagnosis and treatment of the CAM were analysed. There were 12 paediatric patients of CAM were enrolled in this study. Results: Out of 12 paediatric patients of CAM, there were eight male and four female patients, aged from 3 years to 16 years. Out of the 12 patients, 3 were diabetic (25%). Three patients (25%) were taking prolonged systemic steroids with prolonged hospital ICU stay. Two children (16.66%) were under chemotherapy for acute leukaemia. The common clinical symptoms were facial swelling, facial pain, nasal block and nasal discharge. Diagnosis was confirmed by histological examination. All were treated with endoscopic surgical debridement and amphotericin B. Two patients were passed away; one was due to cerebral involvement and another was due to respiratory failure by pneumonia. Conclusions: Early identification and prompt treatment in paediatric patients with CAM are required. Aggressive endoscopic surgical debridement for local control and appropriate systemic antifungal treatment will help to improve the prognosis and survival of the patients. [ABSTRACT FROM AUTHOR]

Aim: Burkitt's lymphoma (BL) is an aggressive type of B-cell non-Hodgkin's lymphoma. BL is common in paediatric age in regions where malaria is holoendemic. Its incidence is also high in immunosuppressed patients in non-endemic regions, especially when associated with HIV infection. Primary BL at the nasopharynx in the paediatric age group is extremely rare, especially in non-endemic areas. It often results in misdiagnosis and delayed treatment. BL becomes fatal if untreated or treated late. The aim of this study is to evaluate the clinical presentations, investigations, and treatment of nasopharyngeal BL among paediatric patients in a non-endemic region. Material and methods: This was a retrospective study in which 21 paediatric patients with nasopharyngeal BL were enrolled, with age under 18 years. This study was done between July 2010 and August 2020. Results: There were 21 children with nasopharyngeal BL included in this study; 17 male and 4 female, with a male-to-female ratio of 4.25:1. The most common presenting symptoms were nasal block (100%), epistaxis (71.42%), rhinorrhoea (66.66%), snoring (57.14%), and headache (42.85%). The most common location of the nasopharynx was the roof of the nasopharynx (28.57%), lateral wall (23.805), posterior wall (19.04%), and junction of the roof and posterior wall (28.57%) of the nasopharynx. All the children were treated with methotrexate, vincristine, cyclophosphamide, doxorubicin, and cytarabine. The mortality of the children with BL in this study population was related to longer duration of clinical manifestations and also misdiagnosis before getting the final diagnosis of BL. Conclusions: Paediatric patients with primary nasopharyngeal BL have an excellent survival rate. Early diagnosis and prompt treatment improve the prognosis of nasopharyngeal BL. [ABSTRACT FROM AUTHOR]

Introduction: Headache is a common complaint presented by the patients in daily clinical practice. Anatomical variation of the nose may lead to headache due to contact of nasal mucosa. A i m: The aim of this study is to find out the role of different types of anatomical variations of the nose causing contact point headache in a tertiary care hospital. Material and methods: 108 patients of headache with anatomical variations of nose were studied within period of three years. Careful evaluations of anatomical variations of the nose were done with the help of diagnostic nasal endoscopy and CT scan in chronic headache. These anatomical variations were treated surgically. Data from this group were analyzed. Results and discussion: Among 108 patient of rhinogenic contact point headache, nine distinct types of anatomical variations were seen. Different anatomical variations like septal deviation (35.18%), septal spur (26.85%), middle turbinate concha bullosa (23.14%), hypertrophied inferior turbinate (10.85%), medialized middle turbinate (0.92%), large bulla ethmoidalis (1.85%) and septal bullosa (0.92%) were found in patients with contact point headache. All were treated surgically. Treatment of each anatomical contact point was personalized for every patient. Conclusions: Headache is a common clinical entity and is nearly universal in the course of everyone's life. Pressure of two opposing mucosa in the nasal cavity without evidence of inflammation can beacause of headache or facial pain. There are different anatomical situations leading to rhinogenic contact point headache where each contact point has its own characteristic. [ABSTRACT FROM AUTHOR]

Cd0.9Zn0.1Te crystals were grown using a modified vertical Bridgman growth technique to produce radiation detector grade material. Motivated by the importance of the retrograde solubility problem in II-VI compound semiconductors, particularly CZT, different cool down techniques were used to observe the effects on the secondary phase (SP) size, distribution, density and resulting detector properties. Presented are four of the cool down schemes performed and the results in terms of the secondary phases and charge transport characteristics of the grown crystals. The cooling of the grown ingot to ambient temperatures was done over various lengths of time. The differences between the cool down methods are in the rates of cooling through the retrograde solubility phase. Apart from these cool downs, quenching studies were also performed on some crystal growths giving unique results in terms of the secondary phase distribution and characteristics as radiation detectors. [ABSTRACT FROM AUTHOR]

Aim and Objectives: The clinicopathologic parameters alone are not sufficient to precisely predict if oral potentially malignant disorders (OPMDs) remain unchanged, i.e., without any malignant changes, regress, or advance to oral squamous cell carcinomas (OSCC). Few of the OPMDs, with or without epithelial dysplasia, may transform to frank OSCC. Discovering various molecular markers that can predict OSCC transformation is essential to develop effective therapeutic strategies. GLUT-1 is one of the hypoxia as well as metabolic indicator markers that have been used to study the metabolic activity of the cells. Hence, given by the World Health Organization (WHO), GLUT-1 expression was studied in various grades of dysplasia to see whether it complements the WHO grading system (mild, moderate, and severe)., Materials and Methods: The study was carried out on paraffin-embedded tissues of 10 normal oral mucosa and 30 OPMD cases. OPMD cases were classified into hyperkeratosis, mild dysplasia, moderate dysplasia, and severe dysplasia groups. Immunohistochemistry was carried out to evaluate the expression of GLUT-1 antigen., Results: According to the WHO grading system of dysplasia, 11 (36.66%) cases were classified as hyperkeratosis, 9 (30%) cases were classified as mild dysplasia, 6 (20%) cases as moderate dysplasia, and 4 (13.33%) cases as severe dysplasia. There was a significant increase in GLUT-1 expression from normal to mild, moderate, and severe dysplasia ( p value = 0.00)., Conclusion: The expression of GLUT-1 marker complements the WHO grading system of oral epithelial dysplasia., Clinical Significance: GLUT-1 expression can be used to complement the WHO grading system to grade epithelial dysplasia.