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Results of this study suggest that single incision laparoscopic subtotal pancreatectomy may be safely performed in centers experienced with advanced laparoscopic procedures.

Well designed tunneling green transistor may enable future VLSIs operating at 0.1V. Sub-60mV/decade characteristics have been convincingly demonstrated on 8" wafers. Large I ON at low V DD are possible according to TCAD simulations but awaits verification. V DD scaling will greatly benefit from low (effective) band gap energy, which may be provided by type II heterojunctions of Si/Ge or compound semiconductors.A Looming Barrier to IC Scaling Reducing the voltage V DD is a powerful way to reduce IC energy consumption, which is proportional to V DD 2 . Power usage was kept under control when V DD was reduced in proportion to half-pitch up to 130nm as shown in Fig 1 [1]. The 14nm node is projected to operate at 0.7V, making the power consumption 25x larger than it would be if operated at 0.14V as the past trend suggests. While IC power consumption has been much discussed as a thermal management challenge, it is also responsible for a few percent of the electricity usage and growing fast. MOSFET current cannot rise faster than one decade for every 60mV increase in V g (the subthreshold swing, SS). To reduce V DD to 0.14V with I ON /I OFF ratio of mere 3 decades, SS needs to be 45mV/decade. A low voltage transistor (Green Transistor, gFET) is needed.Green Transistor with Steep Turn On/Off In MOSFETs (and BJTs), a potential barrier is raised and lowered by V g to turn the current on and off (Fig. 2). Due to Boltzmann distribution, some electrons always have sufficient energy to pass over the barrier. The current can only be reduced by the rate of electron density drop with increasing energy, hence the 60 mV/decade limit [1]. To beat this limit, the carriers must not flow over a barrier. They may tunnel through it. Fig. 3 shows a prototype tunnel transistor [1][2][3][4]. Electrons are generated by band-to-band tunneling in the P+ source when the gate voltage bends the energy band to satisfy two conditions-overlap of the valence and conduction bands and the a high electric field or thin tunnel barrier [5]. The generated electrons flow through the surface N-channel to the drain. Fig. 4 shows simulated I d -V g [6] assuming uniform source doping. In all > 3E19 cm -3 cases, steep turn on occurs at the onset of band overlap. Unfortunately the graded source doping profile and the averaging effect of the Poisson equation provide a continuous range of (effective) doping concentration near the tip of the source. At points of lower doping (Fig. 4) the turn-on voltages and electric field (therefore I ON ) are both lower. The envelope of these curves is the IV of a prototype tunnel transistor, with a disappointing sub-V t swing.

Objective: Prediction models have been developed to predict either unilateral or bilateral primary aldosteronism, and these have not been validated externally. We aimed to develop a simplified score to predict both subtypes and validate this externally. Methods: Our development cohort was taken from 165 patients who underwent adrenal vein sampling (AVS) in two Asian tertiary centres. Unilateral disease was determined using both AVS and postoperative outcome. Multivariable analysis was used to construct prediction models. We validated our tool in a European cohort of 97 patients enrolled in the SPARTACUS trial who underwent AVS. Previously published prediction models were also tested in our cohorts. Results: Backward stepwise logistic regression analysis yielded a final tool using baseline aldosterone-to-lowest-potassium ratio (APR, ng/dl/mmol/l), with an area under receiver-operating characteristic curve of 0.80 (95% CI 0.70–0.89). In the Asian development cohort, probability of bilateral disease was 90.0% (with APR <5) and probability of unilateral disease was 91.4% (with APR >15). Similar results were seen in the European validation cohort. Combining both cohorts, probability of bilateral disease was 76.7% (with APR <5), and probability for unilateral was 91.7% (with APR >15). Other models had similar predictive ability but required more variables, and were less sensitive for identifying bilateral PA. Conclusion: The novel aldosterone-to-lowest-potassium ratio is a convenient score to guide clinicians and patients of various ethnicities on the probability of primary aldosteronism subtype. Using APR to identify patients more likely to benefit from AVS may be a cost-effective strategy to manage this common condition.

Structural and electrical properties of HfO 2 and HfO 2 /Gd 2 O 3 gate stacks on p-GaAs substrates have been investigated. It has been demonstrated that the presence of thin layer of Gd 2 O 3 between HfO 2 and GaAs improves metal-oxide-semiconductor device characteristics such as interface state density, accumulation capacitance, frequency dispersion, and leakage current. It is also found that HfO 2 /Gd 2 O 3 stack can reduce the interfacial GaAs-oxide formation, thus reduce the outdiffusion of elemental Ga and As during post-thermal annealing process. Such suppression of outdiffusion significantly improves the electrical properties of the dielectric stacks.