Controllable optical bistability and Fano line shape in a hybrid optomechanical system assisted by Kerr medium: Possibility of all optical switching

We theoretically analyze the optical and optomechanical nonlinearity present in a hybrid system consisting of a quantum dot(QD) coupled to an optomechanical cavity in the presence of a nonlinear Kerr medium, and show that this hybrid system can be used as an all optical switch. A high degree of control and tunability via the QD-cavity coupling strength, the Kerr and the optomechanical nonlinearity over the bistable behavior shown by the mean intracavity optical field and the power transmission of the weak probe field can be achieved.The results obtained in this investigation has the potential to be used for designing efficient all-optical switch and high sensitive sensors for use in Telecom systems.Comment: 18 pages and 7 figures. Comments welcom

The Economic Impact of Lower Extremity Amputations in Diabetics. a Retrospective Study From a Tertiary Care Hospital of Faisalabad, Pakistan

Background: Among the various complications of diabetes, lower-extremity amputation due to diabetic foot is a common problem. In Pakistan, 6-7% of patients with diabetes suffer from diabetic foot ulceration. Objectives: Our primary objective was to explore the frequency of diabetic foot amputations, and the secondary objective was to calculate the economic burden of these preventable surgeries on the health budget of the provincial government. Materials & Methods: It was a retrospective cross-sectional observational study conducted after obtaining approval from the Ethical Review Committee of Allied hospital, Faisalabad Medical University. The data of diabetic foot patients who underwent amputations between July 2017 and December 2017 were retrieved from three Surgical Units (I, II & III), using a purposive sampling technique. All amputations carried out for reasons other than diabetic foot were excluded. The direct medical cost of one diabetic foot amputation was calculated via a local survey of the various private hospitals of Faisalabad. The indirect costs in terms of loss of productivity and disability costs, transport costs, rehabilitation costs were not included in this study. The data were evaluated by using SPSS Version 23. Results: A total of 85 patients were included in our study. The male to female ratio was 2.7 to 1. The mean direct treatment cost for minor amputation was PKR 46926.00 ± 11730.90 ($382.35 ± 95.58), and the mean direct treatment cost for major amputation was PKR 53720.00 ± 12401.24 ($437.71 ± 101.40). Out of 85 amputations, 63 (74%) were major amputations, and the remaining 22 (26%) were minor amputations. The total cost for 63 major amputations was PKR 3,384,360 ($27568.91) and for 22 minor amputation was PKR 1,032,372 ($8409.67). The net cost came out to be PKR 4,416,732 ($35978.59) for all the 85 cases being reported in a tertiary care hospital of Faisalabad for six months. Conclusion: Diabetic foot, a preventable complication of long-term diabetes mellitus, has an economic burden on the hospital budget, which, if adequately addressed via primary prevention programme, can yield not just economical but medical benefits as well

Consensus as a Nash Equilibrium of a Dynamic Game

Consensus formation in a social network is modeled by a dynamic game of a prescribed duration played by members of the network. Each member independently minimizes a cost function that represents his/her motive. An integral cost function penalizes a member's differences of opinion from the others as well as from his/her own initial opinion, weighted by influence and stubbornness parameters. Each member uses its rate of change of opinion as a control input. This defines a dynamic non-cooperative game that turns out to have a unique Nash equilibrium. Analytic explicit expressions are derived for the opinion trajectory of each member for two representative cases obtained by suitable assumptions on the graph topology of the network. These trajectories are then examined under different assumptions on the relative sizes of the influence and stubbornness parameters that appear in the cost functions.Comment: 7 pages, 9 figure, Pre-print from the Proceedings of the 12th International Conference on Signal Image Technology and Internet-based Systems (SITIS), 201

Formation of Pancreatoduodenal Fistula in Intraductal Papillary Mucinous Neoplasm of the Pancreas Decreased the Frequency of Recurrent Pancreatitis

Intraductal papillary mucinous neoplasms (IPMN) of the pancreas are characterized by proliferation of mucin-secreting cells in the main pancreatic duct (PD) or its branches. The secreted thick mucin usually leads to PD obstruction and dilation. A common complication of IPMN is recurrent acute pancreatitis secondary to poor pancreatic fluid drainage, and rarely, pancreatobiliary and pancreatointestinal fistulae. We describe a unique case of IPMN in a 57-year-old male who was referred to our institution for evaluation of recurrent acute pancreatitis. After extensive evaluation, he was diagnosed with main duct IPMN. Intraductal PD biopsy revealed intestinal type IPMN with intermediate grade dysplasia. Patient was managed clinically by large caliber (10 French) PD stenting which eliminated his recurrent acute pancreatitis. The patient was initially referred for pancreatic resection; however, surgery was aborted and evaluated to be high risk with high morbidity secondary to the extensive adhesions between the pancreas and surrounding structures. Patient remained clinically stable for a few years except for an episode of acute pancreatitis that happened after a trial of stent removal. Subsequently, the patient did well after the PD stent was replaced. Recently, repeat abdominal imaging revealed a large pancreatoduodenal fistula which was confirmed on repeat endoscopic retrograde cholangiopancreatography. We were able to perform pancreatoscopy by advancing a regular upper scope through the fistula and into the PD. Interestingly, the fistula relieved the symptoms of obstruction and subsequently decreased the frequency of recurrent pancreatitis episodes with no further episodes at 6 months follow-up. This case highlights the importance of providing adequate PD drainage to reduce the frequency of recurrent acute pancreatitis in the setting of main duct IPMN, especially if the patient is not a surgical candidate. Also, physicians need to monitor for complications such as fistula formation between the pancreas and surrounding structures in the setting of chronic inflammation due to recurrent episodes of pancreatitis. Early identification of a fistula is important for surgical planning. Furthermore, since recent studies suggested a higher incidence of additional primary malignancies in patients with IPMN of the pancreas compared to the general population, patients may be considered for screening for other primary malignancies