ISX toroidal field coil design and analysis

Structural design and analysis aspects of the toroidal field coils for the Impurity Study Experiment (ISX) tokamak are discussed. The overall mechanical design of ISX is predicated on the ability to remove the upper segment of the toroidal field coils to allow access to the toroidal vacuum vessel. The high current, 120 kA, capability of the new 74 MW power supply, coupled with the modest field requirement of ISX, allows the use of room temperature copper coils. Seventy-two turns, grouped into 18 coils, generate a magnet field of 18 kG at the major radius of 90 cm. Finite element structural analysis codes were utilized to determine the distribution of stresses and deflections around a typical turn. Initial material distribution on a coil was sized using the two-dimensional program FEATS. The resulting coil design was then coupled to the center bucking and out-of-plane restraint systems utilizing the NASTRAN code. The boundary conditions for the analytical models used in the two programs were then iterated, reaching satisfactory agreement as to stress contours and location for the joints. (auth

Rapid threshold estimation using the chained-stimuli technique for auditory brain stem response measurement.

The chained-stimuli technique for rapid auditory brain stem response (ABR) threshold estimation involves lengthening the averaging time window and presenting a series ( chain ) of click stimuli. Each stimulus chain contains, in addition to a silent interval, click stimuli of 10, 20, 30, 40, 50, 60, and 70 dB nHL that are separated by 10 msec intervals. Using this method, the single averaged response to the chained-stimulus contains up to seven individual ABRs. The responses elicited by each level of click stimulus within the chain can be analyzed separately. In this study, chained-stimuli ABR threshold estimations for normal hearers were essentially equivalent to those obtained using an automated conventional ABR method. The data for a seven point latency-intensity function using the chained-stimuli technique were obtained in a mean time of only 8 min per ear

Neoadjuvant Therapy for Resectable Pancreatic Cancer: A New Standard of Care. Pooled Data From 3 Randomized Controlled Trials

Objective: The aim of this study was to pool data from randomized controlled trials (RCT) limited to resectable pancreatic ductal adenocarcinoma (PDAC) to determine whether a neoadjuvant therapy impacts on disease-free survival (DFS) and surgical outcome.Summary Background Data: Few underpowered studies have suggested benefits from neoadjuvant chemo (± radiation) for strictly resectable PDAC without offering conclusive recommendations.Methods: Three RCTs were identified comparing neoadjuvant chemo (± radio) therapy vs. upfront surgery followed by adjuvant therapy in all cases. Data were pooled targeting DFS as primary endpoint, whereas overall survival (OS), postoperative morbidity, and mortality were investigated as secondary endpoints. Survival endpoints DFS and OS were compared using Cox proportional hazards regression with study-specific baseline hazards.Results: A total of 130 patients were randomized (56 in the neoadjuvant and 74 in the control group). DFS was significantly longer in the neoadjuvant treatment group compared to surgery only [hazard ratio (HR) 0.6, 95% confidence interval (CI) 0.4-0.9] (P = 0.01). Furthermore, DFS for the subgroup of R0 resections was similarly longer in the neoadjuvant treated group (HR 0.6, 95% CI 0.35-0.9, P = 0.045). Although postoperative complications (Comprehensive Complication Index, CCI®) occurred less frequently (P = 0.008), patients after neoadjuvant therapy experienced a higher toxicity, but without negative impact on oncological or surgical outcome parameters.Conclusion: Neoadjuvant therapy can be offered as an acceptable standard of care for patients with purely resectable PDAC. Future research with the advances of precision oncology should now focus on the definition of the optimal regimen