Article

Headaches and pineal cysts.

Instituto Israelita de Ensino e Pesquisa Hospital Albert Einstein, Al Joaquim Eugenio de Lima, 881 cj 708, 01403-001, Sao Paulo, Brazil.
Headache The Journal of Head and Face Pain (Impact Factor: 3.19). 04/2010; 50(4):666-8. DOI: 10.1111/j.1526-4610.2010.01652.x
Source: PubMed
0 Followers
 · 
89 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The well known methods for survivor path storage and decoding are the register-exchange method (REM) and the trace-back method (TBM). The REM is conceptually simple, but it is not appropriate for VLSI implementation because it requires large power consumption and large chip area. The TBM is the preferred method in the VLSI implementation of Viterbi decoders (VD) having large constraint length and high performance. However, the TBM requires last-in-first-out (LIFO) buffer and has to use multiple read operations for high speed operation. This multiple operation results in complex control logic. In this paper, we propose a new survivor memory management method called trace-delete method (TDM) and realize this algorithm in hardware (H/W) for VLSI implementation and we compare the TDM with the TBM in terms of latency, the number of memory elements, and the requirements of control logic. The main advantage of the proposed method can be found as short latency and less requirements on additional control logic. Especially, if we combine the TDM with block interleaving the implementation is even simpler than the TBM. The method is studied with particular relevance to HDTV.
    Proceedings - ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing 06/1996; 6:3284-3286. DOI:10.1109/ICASSP.1996.550578
  • [Show abstract] [Hide abstract]
    ABSTRACT: Compton cameras have certain applications requiring portability. Camera designs which improve the portability of these devices by using room-temperature semiconductor and position-sensitive scintillation detectors have been investigated. Models have been developed and tested for the angular image resolution and energy resolution of the camera. A critical component of the models is a Monte Carlo code for simulating the light collection in the position-sensitive scintillator. Model testing has been accomplished with measurements made using a simplified camera having only one room-temperature Si(Li) detector and one position-sensitive NaI(Tl) detector. The model accurately matches measured resolutions over the energy range from 0.66 to 2.75 MeV. The efficiency and time resolution of the portable camera designs have also been investigated. The models predict the angular image resolution for a camera based on room-temperature Si(Li) and NaI(Tl) detectors to be between 9 and 5 degrees for incident photons from 0.5 to 3.0 MeV. The resolution of a camera with a CsI(Tl) detector in place of the NaI(Tl) is predicted to improve the resolution to between 7 and 4 degrees in this energy range
    Nuclear Science Symposium, 1996. Conference Record., 1996 IEEE; 12/1996
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Pineal cysts (PCs) are benign and often asymptomatic lesions of the pineal region that are typically small and do not change in size over time. PCs appear as small, well circumscribed, unilocular masses that either reside within or completely replace the pineal gland. This article reviews and discusses the characteristic features of PCs-clinical, histological, and identifiable by various imaging modalities-which assist clinicians in narrowing the differential diagnosis for pineal lesions.
    Neurosurgery clinics of North America 07/2011; 22(3):341-51, vii. DOI:10.1016/j.nec.2011.06.001 · 1.54 Impact Factor