503 research outputs found
Noise characteristics of passive components for phased array applications
The results of a comparative study on noise characteristics of basic power combining/dividing and phase shifting schemes are presented. The theoretical basics of thermal noise in a passive linear multiport are discussed. A new formalism is presented to describe the noise behavior of the passive circuits, and it is shown that the fundamental results are conveniently achieved using this description. The results of analyses concerning the noise behavior of basic power combining/dividing structures (the Wilkinson combiner, 90 deg hybrid coupler, hybrid ring coupler, and the Lange coupler) are presented. Three types of PIN-diode switch phase shifters are analyzed in terms of noise performance
Editorial Special Issue on Enhancement Algorithms, Methodologies and Technology for Spectral Sensing
The paper is an editorial issue on enhancement algorithms, methodologies and technology for spectral sensing and serves as a valuable and useful reference for researchers and technologists interested in the evolving state-of-the-art and/or the emerging science and technology base associated with spectral-based sensing and monitoring problem. This issue is particularly relevant to those seeking new and improved solutions for detecting chemical, biological, radiological and explosive threats on the land, sea, and in the air
A first-in-human, randomized, controlled, subject- and reviewer-blinded multicenter study of Actamax™ Adhesion Barrier
Purpose:
Post-surgical adhesions remain a significant concern following abdominopelvic surgery. This study was to assess safety, manageability and explore preliminary efficacy of applying a degradable hydrogel adhesion barrier to areas of surgical trauma following gynecologic laparoscopic abdominopelvic surgery.
Methods:
This first-in-human, prospective, randomized, multicenter, subject- and reviewer-blinded clinical study was conducted in 78 premenopausal women (18–46 years) wishing to maintain fertility and undergoing gynecologic laparoscopic abdominopelvic surgery with planned clinically indicated second-look laparoscopy (SLL) at 4–12 weeks. The first two patients of each surgeon received hydrogel, up to 30 mL sprayed over all sites of surgical trauma, and were assessed for safety and application only (n = 12). Subsequent subjects (n = 66) were randomized 1:1 to receive either hydrogel (Treatment, n = 35) or not (Control, n = 31); 63 completed the SLL.
Results:
No adverse event was assessed as serious, or possibly device related. None was severe or fatal. Adverse events were reported for 17 treated subjects (17/47, 36.2%) and 13 Controls (13/31, 41.9%). For 95.7% of treated subjects, surgeons found the device “easy” or “very easy” to use; in 54.5%, some residual material was evident at SLL. For 63 randomized subjects who completed the SLL, adjusted between-group difference in the change from baseline adhesion score demonstrated a 41.4% reduction for Treatment compared with Controls (p = 0.017), with a 49.5% reduction (p = 0.008) among myomectomy subjects (n = 34).
Conclusion:
Spray application of a degradable hydrogel adhesion barrier during gynecologic laparoscopic abdominopelvic surgery was performed easily and safely, without evidence of clinically significant adverse outcomes. Data suggest the hydrogel was effective in reducing postoperative adhesion development, particularly following myomectomy
Light Ions Response of Silicon Carbide Detectors
Silicon carbide (SiC) Schottky diodes 21 mum thick with small surfaces and
high N-dopant concentration have been used to detect alpha particles and low
energy light ions. In particular 12C and 16O beams at incident energies between
5 and 18 MeV were used. The diode active-region depletion-thickness, the
linearity of the response, energy resolution and signal rise-time were measured
for different values of the applied reverse bias. Moreover the radiation damage
on SiC diodes irradiated with 53 MeV 16O beam has been explored. The data show
that SiC material is radiation harder than silicon but at least one order of
magnitude less hard than epitaxial silicon diodes. An inversion in the signal
was found at a fluence of 10^15 ions/cm^2.Comment: 20 pages, 16 figures, submitted for publication to Nuclear
Instruments and Methods in Physics Research
Bandwidth Allocation and Reservation - End-to-End Specification
The Bandwidth Allocation and Reservation (BAR) activity within JRA4 of the EGEE project specified and implemented the necessary components and interfaces to enable the EGEE Grid middleware to request and use guaranteed bandwidth services. This report describes the components and interfaces required for an end-to-end BAR service and how they interact
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