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Introduction: Clostridium Difficile infection (CDI) following restoration of intestinal continuity is uncommon and may progress to fulminant colitis. Fulminant CDI is associated with significant morbidity and mortality. In an unwell patient without clear evidence of an anastomotic leak, surgeons should be aware of the possibility of CDI and institute appropriate management. Presentation of Case: We report the case of a 71- year-old man, who presented for an elective loop ileostomy reversal after an ultra-low anterior resection for a low rectal cancer eight months prior. The patient deteriorated clinically on post-operative day (POD) 4 and by POD 5 was in septic shock with multi-organ failure. A relook laparotomy confirmed no anastomotic leak and a flexible sigmoidoscopy revealed typical appearance of pseudomembranous colitis. The patient continued to deteriorate in the intensive care unit despite oral and rectal Vancomycin. An abdominal computed tomography (CT)1 on POD 9 demonstrated severe pancolitis and enteritis necessitating surgical intervention. He underwent an emergency subtotal colectomy with an end ileostomy after failing medical management. Discussion: Many factors have been shown to increase the incidence of Clostridium difficile colonization in the colon including recent hospitalization, antibiotic use, and length of defunctioning beyond six months. The presence of risk factors associated with an increase in CDI such as proton pump inhibitor use, steroid use or immunosuppression and advanced age may allow surgeons to predict high risk patients. Conclusion: Although rare, fulminant CDI following reversal of ileostomy is a potentially fatal condition. Surgeons should be aware of the risk factors predisposing patients to CDI particularly in a patient with an acute abdomen without clear evidence of an anastomotic leak.

We discuss a possibility of restricting parameters in N=2 supergravity based on axion observations. We, accordingly, derive conditions that prepotential and gauge couplings should satisfy. Such conditions not only allow us to constrain the theory but also provide the lower bound of the N=2→N=1 breaking scale.

A novel strain engineering is reported to realize enhancement-mode high electron mobility transistors (HEMTs) with ultralow specific on-resistance ( $\boldsymbol{R}_{\mathbf{on},\mathbf{sp}}$ ) fabricated on 200 mm CMOS-compatible process platform. In this scheme, a strain enhancement layer deposited on the access region of HEMT by a low cost CVD process is demonstrated to reduce $\boldsymbol{R}_{\mathbf{on},\mathbf{sp}}$ . As comparing to 100 V-rated HEMT without the strain layer, HEMT with the strain layer features comparable $\boldsymbol{V}_{\mathbf{th}}$ of +1.5 V but significant $\boldsymbol{R}_{\mathbf{on},\mathbf{sp}}$ reduction of 24% and 28% at ambient temperatures of 25 °C and 150 °C, respectively. The proposed device exhibits the off-state drain-to-source breakdown voltage increases about 12%. System verification shows that high efficiency of 92.7% which is higher than the state-of-art Si MOSFET about 3% with stable burn-in performance. This work achieves a record low $\boldsymbol{R}_{\mathbf{on},\mathbf{sp}}$ in 100 V rating commercially available GaN and Si power transistors.

Objectives Melanoma treatment in the elderly can entail complex decision making. This study characterizes the presentation, management, and outcome of melanoma in the very elderly. Method Retrospective review of all patients in their 85th year or older presenting to a tertiary referral cancer centre between 2000 and 2012 with American Joint Committee on Cancer stages 0–II cutaneous melanoma. Results 127 patients, 26 with in-situ disease and 101 with stages I–II disease, were included. For invasive primary disease, the median age was 87 years (IRQ = 86–89). Most patients had melanomas with poor prognoses at diagnosis: 49.5% were ulcerated, 68.3% mitotically active (mitotic rate ≥ 1), and the median tumor thickness was 3.7 mm (IQR = 1.7–5.8). Nodular melanomas were the most frequent subtype (31.7%, 32/101). Only 66.3% received an excision margin ≥ 10 mm. Suboptimal excision margins were associated with increased risk of local recurrence (HR = 6.87, 95% CI = 5.53–8.20, p = 0.0045) but not poorer disease specific survival (DSS, p = 0.37) or overall survival (OS, p = 0.19). Sentinel node biopsy (SNB) did not influence survival (DSS, p = 0.39, OS, p = 0.78). Median OS was 33 months. Overall, one-third (34.7%) of patients died from causes other than melanoma during the follow up period. In patients aged ≥ 90 only 1 patient (4.3%) died from melanoma, while 10 patients (43.5%) died of other causes. Conclusions Older patients have thick, mitotically active and frequently ulcerated melanomas. An excision margin ≥ 10 mm should be considered to reduce risk of local recurrence. SNB did not impact on survival. With increasing age, patients will more commonly die of causes other than melanoma regardless of the extent of surgical care.