scholarly journals Medical optical imaging: Signal processing leads to new methods of detecting life-threatening situations [Special Reports]

2017 ◽  
Vol 34 (6) ◽  
pp. 17-20
Author(s):  
John Edwards
Keyword(s):  
Signal Processing ◽  
Optical Imaging ◽  
New Methods ◽  
Life Threatening

The Evolution of Lead Extraction

2009 ◽  
Vol 5 (1) ◽  
pp. 32
Author(s):  
Melanie Maytin ◽  
Laurence M Epstein ◽  
◽  
Keyword(s):  
Natural Selection ◽  
Lead Extraction ◽  
Significant Morbidity ◽  
Extraction Techniques ◽  
Extraction Technology ◽  
Device Management ◽  
Future Developments ◽  
The Past ◽  
New Methods ◽  
Life Threatening

Prior to the introduction of successful intravascular countertraction techniques, options for lead extraction were limited and dedicated tools were non-existent. The significant morbidity and mortality associated with these early extraction techniques limited their application to life-threatening situations such as infection and sepsis. The past 30 years have witnessed significant advances in lead extraction technology, resulting in safer and more efficacious techniques and tools. This evolution occurred out of necessity, similar to the pressure of natural selection weeding out the ineffective and highly morbid techniques while fostering the development of safe, successful and more simple methods. Future developments in lead extraction are likely to focus on new tools that will allow us to provide comprehensive device management and the design of new leads conceived to facilitate future extraction. With the development of these new methods and novel tools, the technique of lead extraction will continue to require operators that are well versed in several methods of extraction. Garnering new skills while remembering the lessons of the past will enable extraction technologies to advance without repeating previous mistakes.

scholarly journals Improved methods for signal processing in measurements of mercury by Tekran<sup>®</sup> 2537A and 2537B instruments

2017 ◽  
Vol 10 (12) ◽  
pp. 5063-5073 ◽  
Author(s):  
Jesse L. Ambrose
Keyword(s):  
Signal Processing ◽  
Thermal Desorption ◽  
Elemental Mercury ◽  
Operating Conditions ◽  
Atomic Fluorescence Spectrometry ◽  
Atomic Fluorescence ◽  
Gaseous Elemental Mercury ◽  
New Methods ◽  
Processing Bias ◽  
Improved Methods

Abstract. Atmospheric Hg measurements are commonly carried out using Tekran® Instruments Corporation's model 2537 Hg vapor analyzers, which employ gold amalgamation preconcentration sampling and detection by thermal desorption (TD) and atomic fluorescence spectrometry (AFS). A generally overlooked and poorly characterized source of analytical uncertainty in those measurements is the method by which the raw Hg atomic fluorescence (AF) signal is processed. Here I describe new software-based methods for processing the raw signal from the Tekran® 2537 instruments, and I evaluate the performances of those methods together with the standard Tekran® internal signal processing method. For test datasets from two Tekran® instruments (one 2537A and one 2537B), I estimate that signal processing uncertainties in Hg loadings determined with the Tekran® method are within ±[1 % +  1.2 pg] and ±[6 % + 0.21 pg], respectively. I demonstrate that the Tekran® method can produce significant low biases (≥  5 %) not only at low Hg sample loadings (<  5 pg) but also at tropospheric background concentrations of gaseous elemental mercury (GEM) and total mercury (THg) (∼  1 to 2 ng m−3) under typical operating conditions (sample loadings of 5–10 pg). Signal processing uncertainties associated with the Tekran® method can therefore represent a significant unaccounted for addition to the overall  ∼  10 to 15 % uncertainty previously estimated for Tekran®-based GEM and THg measurements. Signal processing bias can also add significantly to uncertainties in Tekran®-based gaseous oxidized mercury (GOM) and particle-bound mercury (PBM) measurements, which often derive from Hg sample loadings < 5 pg. In comparison, estimated signal processing uncertainties associated with the new methods described herein are low, ranging from within ±0.053 pg, when the Hg thermal desorption peaks are defined manually, to within ±[2 % + 0.080 pg] when peak definition is automated. Mercury limits of detection (LODs) decrease by 31 to 88 % when the new methods are used in place of the Tekran® method. I recommend that signal processing uncertainties be quantified in future applications of the Tekran® 2537 instruments.

scholarly journals Introduction of New Laryngeal Closure Methods for Patients with Intractable Aspiration

2011 ◽  
Vol 2 ◽  
pp. JCM.S7537 ◽  
Author(s):  
Masaru Tateda ◽  
Tetsuya Yokoyama ◽  
Atsuhiro Mizukawa ◽  
Hiroaki Sato
Keyword(s):  
Blood Loss ◽  
Total Laryngectomy ◽  
Vocal Folds ◽  
Elderly Individuals ◽  
Laryngeal Closure ◽  
New Methods ◽  
Surgical Methods ◽  
Swallowing Problems ◽  
Life Threatening ◽  
Intractable Aspiration

The aging population in Japan has recently resulted in a rapid increase in elderly individuals. Airway management is thus being required more and more often. Aspiration pneumonia is a life-threatening problem among patients with swallowing problems. Several new surgical methods of laryngeal closure that are easier and safer than previous methods have been developed. Among these new methods, we have performed the Kano method as closure of the larynx using double flaps of the divided craniad vocal folds and the divided caudad vocal folds with partial resection of the thyroid and cricoid cartilages for patients with intractable aspiration. We encountered minor leakage in two patients, but these soon closed spontaneously. This procedure is less invasive than other methods such as total laryngectomy and tracheal separation and has great advantages in terms of low blood loss and short duration of the operation.

Adaptive Anytime Data Transmission of Non-Stationary Signals

2010 ◽  
Vol 14 (3) ◽  
pp. 240-246
Author(s):  
Annamária R. Várkonyi-Kóczy ◽  
◽  
Keyword(s):  
Signal Processing ◽  
Data Transmission ◽  
Transmission Channel ◽  
New Methods ◽  
Signal Representations ◽  
Norm Minimization ◽  
Stationary Signals ◽  
Signal Processing Algorithms ◽  
Processing Algorithms ◽  
Signal Coding

The never unseen information explosion in data transmission and communication called for new methods in signal coding and reconstruction. To minimize the channel capacity needed for the transmission urged researchers to find techniques which are flexible and can adapt to the available space and time. Anytime techniques are good candidates for such purposes. If the signal/data to be transmitted can be characterized as sequence of stationary intervals overcomplete signal representations can be applied. These techniques can be operated in an anytime manner as well, i.e., are excellent tools for handling the capacity problems. This paper introduces the concept of anytime recursive overcomplete signal representations using different recursive signal processing algorithms. The novelty of the approach is that an on-going set of signal transformations together with appropriate (e.g., L1 norm) minimization procedures can provide optimal and flexible anytime on-going representations, on-going signal segmentations into stationary intervals, and on-going feature extractions for immediate utilization in data transmission, communication, diagnostics, or other applications. The proposed technique may be advantageous if the transmission channel is overloaded and in case of processing non-stationary signals when complete signal representations can be used only with serious limitations because of their relative weakness in adaptive matching of signal structures.

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