Philips

About: Philips is a company organization based out in Vantaa, Finland. It is known for research contribution in the topics: Signal & Layer (electronics). The organization has 68260 authors who have published 99663 publications receiving 1882329 citations. The organization is also known as: Koninklijke Philips Electronics N.V. & Royal Philips Electronics.

Generalized translinear circuit principle

Abstract: It is shown that a generalized interpretation of the translinear (TL) principle leads quite naturally to an extension to MOS circuits. It is shown that two distinct classes of TL circuits exist, one suitable for bipolar and the other for MOS implementation. The MOS-translinear (MTL) circuit principle is derived and an initial classification of simple MTL circuits is proposed. Some examples are given of MTL circuits synthesizing nonlinear functions. >

Safety, efficacy, and functionality of high-field strength interventional magnetic resonance imaging for neurosurgery.

Abstract: Objective Interventional magnetic resonance imaging (MRI) allows neurosurgeons to interactively perform surgery using MRI guidance. High-field strength (1.5-T) imaging permits exceptional observation of intracranial and spinal pathological features. The development of this technology and its application to a variety of neurosurgical procedures are described. Methods We report on the first 101 cases that were treated in the interventional MRI unit (between January 1997 and September 1998). These cases included 39 brain biopsies, 30 tumor resections, 9 functional neurosurgical cases, 8 cyst drainages, 5 laminectomies, and 10 miscellaneous cases. Patients ranged in age from 14 months to 84 years (median, 43 yr); 61 patients were male and 40 were female. Intraoperative functional techniques that were used to influence surgical decision-making included magnetic resonance spectroscopy, functional MRI, magnetic resonance angiography and venography, chemical shift imaging, and diffusion-weighted imaging. All surgery was performed using MRI-compatible instruments within the 5-gauss line and conventional instruments outside that line. Results All 39 brain biopsies yielded diagnostic tissue. Of the 30 tumor resections, 24 (80%) were considered radiographically complete. The incidence of serious complications was low and was comparable to that associated with conventional operating rooms. One patient developed a Propionibacterium acnes brain abscess 6 weeks after surgery and another patient experienced Staphylococcus aureus scalp cellulitis after a brain biopsy, yielding an infection rate of less than 2%. No clinically significant hemorrhage was observed in immediate postoperative imaging scans, although one patient developed a delayed hematoma after a thalamotomy. One patient experienced a stroke after resection of a hippocampal tumor. No untoward events were associated with MRI-compatible instrumentation or intraoperative patient monitoring. Conclusion High-field (1.5-T) interventional MRI is a safe and effective technology for assisting neurosurgeons in achieving the goals of surgery. Preliminary results suggest that the functional capabilities of this technology can yield data that can significantly influence intraoperative neurosurgical decision-making. The rates of serious complications, such as infection, associated with this new technology were low.

Methodological consensus on clinical proton MRS of the brain: Review and recommendations

Abstract: Proton MRS (1 H MRS) provides noninvasive, quantitative metabolite profiles of tissue and has been shown to aid the clinical management of several brain diseases. Although most modern clinical MR scanners support MRS capabilities, routine use is largely restricted to specialized centers with good access to MR research support. Widespread adoption has been slow for several reasons, and technical challenges toward obtaining reliable good-quality results have been identified as a contributing factor. Considerable progress has been made by the research community to address many of these challenges, and in this paper a consensus is presented on deficiencies in widely available MRS methodology and validated improvements that are currently in routine use at several clinical research institutions. In particular, the localization error for the PRESS localization sequence was found to be unacceptably high at 3 T, and use of the semi-adiabatic localization by adiabatic selective refocusing sequence is a recommended solution. Incorporation of simulated metabolite basis sets into analysis routines is recommended for reliably capturing the full spectral detail available from short TE acquisitions. In addition, the importance of achieving a highly homogenous static magnetic field (B0 ) in the acquisition region is emphasized, and the limitations of current methods and hardware are discussed. Most recommendations require only software improvements, greatly enhancing the capabilities of clinical MRS on existing hardware. Implementation of these recommendations should strengthen current clinical applications and advance progress toward developing and validating new MRS biomarkers for clinical use.

Adaptive Persuasive Systems: A Study of Tailored Persuasive Text Messages to Reduce Snacking

Abstract: This article describes the use of personalized short text messages (SMS) to reduce snacking. First, we describe the development and validation (N = 215) of a questionnaire to measure individual susceptibility to different social influence strategies. To evaluate the external validity of this Susceptibility to Persuasion Scale (STPS) we set up a two week text-messaging intervention that used text messages implementing social influence strategies as prompts to reduce snacking behavior. In this experiment (N = 73) we show that messages that are personalized (tailored) to the individual based on their scores on the STPS, lead to a higher decrease in snacking consumption than randomized messages or messages that are not tailored (contra-tailored) to the individual. We discuss the importance of this finding for the design of persuasive systems and detail how designers can use tailoring at the level of social influence strategies to increase the effects of their persuasive technologies.

LED driver circuit with PWM output

Abstract: The driver circuit for light emitting diodes (LEDs) of the present invention provides power to LEDs using pulse width modulation (PWM). The driver circuit 100 uses current feedback to adjust power to LED arrays 54 and provides a full light and a dim mode.