A mathematical model of brain glucose homeostasis

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The role of liver transplantation techniques in the surgical management of advanced renal urothelial carcinoma with or without inferior vena cava thrombus

Purpose: Standard radical nephrectomy for large masses is significantly facilitated by liver transplantation techniques, which have been successfully employed over the last ten years at our institution. Large and locally-advanced urothelial carcinoma of the kidney with or without extension into the inferior vena cava is rare. The purpose of this study was to present the surgical management of large and locally-advanced urothelial tumors arising from the renal pelvis using liver transplantation techniques and to evaluate patient outcome. Materials and Methods: Diagnostic work-up and surgical management of 4 patients with large and locally-advanced renal urothelial carcinoma were retrospectively reviewed. Two out of four patients with urothelial carcinoma presented with inferior vena cava thrombus. Mean tumor size was 11.6 cm. All patients underwent surgery, 2 patients with the presumed diagnosis of renal cell cancer. Liver transplantation techniques were an integral part in all radical nephrectomies. Results: No intraoperative complications and postoperative mortality occurred. Mean operative time was 7.5 hours, estimated blood loss was 1.5 L, and an average of 4.8 units of blood was transfused intraoperatively. Three patients succumbed to cancer recurrence at a mean postoperative time of 6.3 months; 1 patient is still alive 24 months after surgery. Conclusions: Large and locally-advanced renal masses of urothelial origin can be successfully removed by a combination of radical nephrectomy with liver transplantation techniques. Since long-term outcome of such patients has been poor, accurate preoperative diagnosis is essential to consider neoadjuvant treatment and to plan nephroureterectomy

Perceptions of Efficacy, Control and Risk: A Theory of Mixed Control

We prove a multivariable elliptic analogue of Jackson’s 8W7 summation formula, which was recently conjectured by S. O. Warnaar

Perceptions of Efficacy, Control and Risk: A Theory of Mixed Control

Based on the aggregated insights of the existing theories related to multiple sources of efficacy and locus of control, we introduce the theory of mixed control, a model of compound-risk perception. This theory considers outcome expectancies as being composed of expectancies regarding three distinct sources of risk (self, others, and chance). This reflects that entrepreneurship is a complex and dynamic activity, involving multiple sources of risk. Beliefs about the efficacy of these elements are weighted by the degree to which these elements are perceived to control the outcome. The interaction of efficacy and control beliefs is therefore at the core of our theory. Further, we discuss that risks are not only subjectively perceived but can be endogenous and depend on future decisions and actions of the entrepreneur