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Background: Ileal perforations have a diverse etiology and often present with perforative peritonitis in the surgical emergency. This study is based on the scenario of management of ileal perforation encountered in a tertiary teaching hospital in West Bengal. Aims and Objectives: The aim and objective of this study is to document and evaluate the post-operative outcome based on the diverse etiopathology, clinical presentation, and surgical management performed in patients having ileal perforation. Materials and Methods: A prospective crosssectional observational study was conducted in the Deben Mahata Government Medical College, Purulia, West Bengal, for a period of 2 years from February 2020 to January 2022 with 60 patients introperatively diagnosed with ileal perforation. Emergency exploratory laparotomy was done in all the cases presenting with perforative peritonitis. Ileal perforation was identified and an edge biopsy was taken. Appropriate surgical treatment in the forms of primary repair/resection-anastomosis/resection-ileostomy was done. The histopathological report was reviewed following surgery. The patients were evaluated in the post-operative period for post-operative morbidity and mortality. Results: Typhoid fever (68.33%) was the predominant cause in our study. The most common symptoms were abdominal pain (93%), fever (85%), and abdominal distension (75%). Widal test was performed preoperatively and was positive in 41 cases (68.33%). In our study, primary repair (58.33%), resectionanastomosis (15%), and resection-ileostomy (26.67%) were the main surgical treatment performed. Sepsis, surgical site infections (SSIs), fecal fistula, and wound dehiscence were the common post-operative complications found. Among them, SSI (51.67%) was the most common post-operative complication (P<0.0001) found and fecal fistula was the most dreaded post-operative complication with 50% mortality. Histopathological reports following surgery showed cases were mainly due to enteric fever (51.67%) and tuberculosis (25%). Conclusion: Early surgical intervention was the mainstay of treatment of ileal perforation. Delayed presentation of perforation is responsible for the development of surgical site infections (SSIs). Uncontrolled generalized sepsis, wound dehiscence, and fecal fistula were the main causes of post-operative mortality. [ABSTRACT FROM AUTHOR]

Small polaron formation is known to limit the photocatalytic charge transport efficiency of hematite via ultrafast carrier self-trapping. While small polaron formation is known to occur in bulk hematite, a complete description of surface polaron formation in this material is not fully understood. Theoretical predictions indicate that the kinetics and thermodynamics of surface polaron formation are different than those in bulk. However, to test these predictions requires the ability to experimentally differentiate polaron formation dynamics at the surface. Near grazing angle extreme ultraviolet reflection-absorption (XUV-RA) spectroscopy is surface sensitive and provides element and oxidation state specific information on a femtosecond time scale. Using XUV-RA, we provide a systematic comparison between surface and bulk polaron formation kinetics and energetics in photoexcited hematite. We find that the rate of surface polaron formation (250 ± 40 fs) is about three times slower than bulk polaron formation (90 ± 5 fs) in photoexcited hematite. Additionally, we show that the surface polaron formation rate can be systematically tuned by surface molecular functionalization. Within the framework of a Marcus type model, the kinetics and energetics of polaron formation are discussed. The slower polaron formation rate observed at the surface is found to result from a greater lattice reorganization relative to bulk hematite, while surface functionalization is shown to tune both the lattice reorganization as well as the polaron stabilization energies. The ability to tune the kinetics and energetics of polaron formation and hopping by molecular functionalization provides the opportunity to synthetically control electron transport in hematite. [ABSTRACT FROM AUTHOR]