Clinical problems in long-duration fetal magnetocardiogram recording

AbstractThe occurrence of LDE-type flares in the last three cycles has been investigated. The Fourier analysis spectrum was calculated for the time series of the LDE-type flare occurrence during the 20-th, the 21-st and the rising part of the 22-nd cycle. LDE-type flares (Long Duration Events in SXR) are associated with the interplanetary protons (SEP and STIP as well), energized coronal archs and radio type IV emission. Generally, in all the cycles considered, LDE-type flares mainly originated during a 6-year interval of the respective cycle (2 years before and 4 years after the sunspot cycle maximum). The following significant periodicities were found:• in the 20-th cycle: 1.4, 2.1, 2.9, 4.0, 10.7 and 54.2 of month,• in the 21-st cycle: 1.2, 1.6, 2.8, 4.9, 7.8 and 44.5 of month,• in the 22-nd cycle, till March 1992: 1.4, 1.8, 2.4, 7.2, 8.7, 11.8 and 29.1 of month,• in all interval (1969-1992):a)the longer periodicities: 232.1, 121.1 (the dominant at 10.1 of year), 80.7, 61.9 and 25.6 of month,b)the shorter periodicities: 4.7, 5.0, 6.8, 7.9, 9.1, 15.8 and 20.4 of month.Fourier analysis of the LDE-type flare index (FI) yields significant peaks at 2.3 - 2.9 months and 4.2 - 4.9 months. These short periodicities correspond remarkably in the all three last solar cycles. The larger periodicities are different in respective cycles.

Download Full-text

Specimen Preparation for Clinical Applications of X-Ray Microanalysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135241 ◽

1990 ◽

Vol 48 (2) ◽

pp. 328-329

Author(s):

J.D. Shelburne ◽

G.M. Roomans

Keyword(s):

Carbon Coating ◽

Clinical Applications ◽

Point Of View ◽

Practical Significance ◽

Sweat Test ◽

Specimen Preparation ◽

Tissue Preparation ◽

X Ray ◽

Gallbladder Stones ◽

Clinical Problems

Proper preparative procedures are a prerequisite for the validity of the results of x-ray microanalysis of biological tissue. Clinical applications of x-ray microanalysis are often concerned with diagnostic problems and the results may have profound practical significance for the patient. From this point of view it is especially important that specimen preparation for clinical applications is carried out correctly.Some clinical problems require very little tissue preparation. Hair, nails, and kidney and gallbladder stones may be examined and analyzed after carbon coating. High levels of zinc or copper in hair may be indicative of dermatological or systemic diseases. Nail clippings may be analyzed (as an alternative to the more conventional sweat test) to confirm a diagnosis of cystic fibrosis. X-ray microanalysis in combination with scanning electron microscopy has been shown to be the most reliable method for the identification of the components of kidney or gallbladder stones.A quantitatively very important clinical application of x-ray microanalysis is the identification and quantification of asbestos and other exogenous particles in lung.

Download Full-text

Transvenous catheter cardioversion with long duration rounded waveforms-initial findings

Journal of Cardiothoracic and Vascular Anesthesia ◽

10.1016/s1053-0770(98)90283-x ◽

1998 ◽

Vol 31 ◽

pp. 45

Author(s):

M HARBINSON

Keyword(s):

Long Duration

Download Full-text

Relation Between Level of Prefrontal Activity and Subject's Performance

Journal of Psychophysiology ◽

10.1027//0269-8803.13.2.117 ◽

1999 ◽

Vol 13 (2) ◽

pp. 117-125 ◽

Cited By ~ 14

Author(s):

Laurence Casini ◽

Françoise Macar ◽

Marie-Hélène Giard

Keyword(s):

Brain Activity ◽

Sensory Information ◽

Practice Phase ◽

Trained Subjects ◽

Anagram Task ◽

Economic Information ◽

Long Duration ◽

Level Of Activity ◽

The Brain ◽

Processing Mechanism

Abstract The experiment reported here was aimed at determining whether the level of brain activity can be related to performance in trained subjects. Two tasks were compared: a temporal and a linguistic task. An array of four letters appeared on a screen. In the temporal task, subjects had to decide whether the letters remained on the screen for a short or a long duration as learned in a practice phase. In the linguistic task, they had to determine whether the four letters could form a word or not (anagram task). These tasks allowed us to compare the level of brain activity obtained in correct and incorrect responses. The current density measures recorded over prefrontal areas showed a relationship between the performance and the level of activity in the temporal task only. The level of activity obtained with correct responses was lower than that obtained with incorrect responses. This suggests that a good temporal performance could be the result of an efficacious, but economic, information-processing mechanism in the brain. In addition, the absence of this relation in the anagram task results in the question of whether this relation is specific to the processing of sensory information only.

Download Full-text

Effects of Fatigue on Cognitive Performance in Long-Duration Simulated Flight Missions

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000191 ◽

2020 ◽

Vol 10 (2) ◽

pp. 82-93

Author(s):

Eduardo Rosa ◽

Ola Eiken ◽

Mikael Grönkvist ◽

Roger Kölegård ◽

Nicklas Dahlström ◽

...

Keyword(s):

Executive Functions ◽

Task Performance ◽

Cognitive Performance ◽

Cognitive Tasks ◽

Fatigue Index ◽

Fighter Aircraft ◽

Long Duration ◽

Metacognitive Accuracy

Abstract. Fighter pilots may be exposed to extended flight missions. Consequently, there is increasing concern about fatigue. We investigated the effects of fatigue and cognitive performance in a simulated 11-hr mission in the 39 Gripen fighter aircraft. Five cognitive tasks were used to assess cognitive performance. Fatigue was measured with the Samn–Perelli Fatigue Index. Results showed that performance in the non-executive task degraded after approximately 7 hr. Fatigue ratings showed a matching trend to the performance in this task. Performance in tasks taxing executive functions did not decline. We interpreted that fatigue can be overridden by increased attentional effort for executive tasks but not for non-executive components of cognition. Participants underestimated their performance and metacognitive accuracy was not influenced by fatigue.

Download Full-text