scholarly journals An Investigation of Navigation Processes in Human Locomotor Behavior

2000 ◽  
Vol 44 (26) ◽  
pp. 233-236 ◽  
Author(s):  
Christi J. Adams ◽  
Robert J. Beaton
Keyword(s):  
Observational Study ◽  
Direct Contact ◽  
Locomotor Behavior ◽  
Ambient Light ◽  
Time To Contact ◽  
Post Hoc Analysis ◽  
Light Levels ◽  
Ambient Lighting ◽  
Time Required ◽  
Post Hoc

An observational study examined how available ambient lighting affected the time required for high attention, fine navigation when approaching a navigation hazard. Low ambient light levels, representing twilight and night conditions, increase the amount of time required for fine navigation. Analysis of variance (ANOVA) showed differences in ambient light levels yielded differences in time to contact for three direct contact hazards and two passing hazards. Under all conditions, post hoc analysis showed responses for Night lighting levels were different from Day lighting levels. Specific comparisons between types of navigation hazards were not contemplated, since perceptual and motor requirements varied considerably among hazards.

Factors influencing mortality in atrial fibrillation. Post hoc analysis of an observational study in outpatients

2005 ◽  
Vol 103 (2) ◽  
pp. 140-144 ◽  
Author(s):  
Claudia Stöllberger ◽  
Maria Winkler-Dworak ◽  
Josef Finsterer ◽  
Elisabeth Hartl ◽  
Pavel Chnupa
Keyword(s):  
Atrial Fibrillation ◽  
Observational Study ◽  
Post Hoc Analysis ◽  
Factors Influencing ◽  
Post Hoc

scholarly journals Systemic Anticoagulant Effect of Low-Dose Subcutaneous Unfractionated Heparin as Determined Using Thrombelastography

2007 ◽  
Vol 35 (4) ◽  
pp. 498-504 ◽  
Author(s):  
S. J. Matzelle ◽  
N. M. Gibbs ◽  
W. Weightman ◽  
M. Sheminant ◽  
R. Rowe ◽  
...  
Keyword(s):  
Observational Study ◽  
Unfractionated Heparin ◽  
Low Dose ◽  
Anticoagulant Effect ◽  
Surgical Patients ◽  
Normal Range ◽  
Blood Samples ◽  
Post Hoc Analysis ◽  
Post Hoc ◽  
Preoperative Creatinine

In an observational study using heparinase-modified thrombelastography, we investigated the percentage of elective cardiothoracic surgical patients receiving low-dose unfractionated heparin (5000 IU 12 hourly subcutaneously) who had a demonstrable systemic heparin effect. Blood samples were obtained at induction from 40 adult elective cardiothoracic surgical patients who had received 5000 IU unfractionated heparin subcutaneously within six hours. Simultaneous kaolin and heparinase-modified thrombelastographies were run on all samples. Fourteen patients (35%; 95% CI: 20 to 50%) had a demonstrable heparin effect(defined as a kaolin thrombelastography R time >25% longer than the heparinase-modified control). Their mean±SD kaolin thrombelastography R time was 13.6±5.9 minutes (normal range 4 to 8 minutes) vs. 7.1±2.0 minutes for the heparinase-modified controls. In 10 patients the thrombelastography R times were >50% longer and in four patients >100% longer, than their respective heparinase-modified controls. In a post hoc analysis, there was little correlation between the extent of the prolongation and patient age (r=0.02), weight (r=-0.31), preoperative creatinine (r=-0.17), or time since administration of heparin (r=0.14). These results indicate that about one third of patients who have received low-dose unfractionated heparin subcutaneously within six hours have a demonstrable heparin effect. The potential for this effect should be considered if central neural blockade is planned.

Nintedanib in IPF: post hoc analysis of the Italian FIBRONET observational study

2020 ◽  
Author(s):  
Venerino Poletti ◽  
Carlo Albera ◽  
Sergio Harari ◽  
Alberto Pesci ◽  
Alessandra Ori ◽  
...  
Keyword(s):  
Observational Study ◽  
Post Hoc Analysis ◽  
Post Hoc

scholarly journals Night-time Lookout Duty: The Role of Ambient Light Levels and Dark Adaptation

2012 ◽  
Vol 65 (4) ◽  
pp. 589-602 ◽  
Author(s):  
Tony Wynn ◽  
Peter A. Howarth ◽  
Bert R. Kunze
Keyword(s):  
Dark Adaptation ◽  
Probability Of Detection ◽  
Working Environment ◽  
Ambient Light ◽  
Night Time ◽  
Lighting Conditions ◽  
Light Levels ◽  
Ambient Lighting ◽  
Small Craft

The aim of this research was to clarify and quantify the demands of the working environment and watch-keeping regime for large commercial ships in relation to dark adaptation. The night lookout task requires the identification of the relatively bright navigational lights of other ships against the dark background of the sky and sea. The probability of detection is determined by the ambient lighting conditions on the bridge and the dark adapted state of vision. Light levels were such that threshold sensitivity (after 15 minutes) was reduced by around 2 log units in comparison to complete darkness. This has implications for the effective range of navigational lights at sea as defined in regulations. The intensity and position of navigation lights on larger vessels is such that the sensitivity of the eye under typical bridge conditions is likely to be sufficient for their visibility to be acceptable. This may not be the case for less well lit small craft.

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