Modeling Violation Behavior at Highway-Rail Grade Crossings Using a Driver Anxiety Surrogate Measure

Abstract A long-standing criticism of the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides) has been the inequity between the internal medicine ratings and the orthopedic ratings; in the comparison, internal medicine ratings appear inflated. A specific goal of the AMA Guides, Sixth Edition, was to diminish, where possible, those disparities. This led to the use of the International Classification of Functioning, Disability, and Health from the World Health Organization in the AMA Guides, Sixth Edition, including the addition of the burden of treatment compliance (BOTC). The BOTC originally was intended to allow rating internal medicine conditions using the types and numbers of medications as a surrogate measure of the severity of a condition when other, more traditional methods, did not exist or were insufficient. Internal medicine relies on step-wise escalation of treatment, and BOTC usefully provides an estimate of impairment based on the need to be compliant with treatment. Simplistically, the need to take more medications may indicate a greater impairment burden. BOTC is introduced in the first chapter of the AMA Guides, Sixth Edition, which clarifies that “BOTC refers to the impairment that results from adhering to a complex regimen of medications, testing, and/or procedures to achieve an objective, measurable, clinical improvement that would not occur, or potentially could be reversed, in the absence of compliance.

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Pilot Study of Advisory On-Board Vehicle Warning Systems at Railroad Grade Crossings: Executive Summary

PsycEXTRA Dataset ◽

10.1037/e591242009-001 ◽

1997 ◽

Keyword(s):

Pilot Study ◽

Warning Systems ◽

Executive Summary ◽

Grade Crossings

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The Systematic Bias of Entropy Calculation in the Multi-Scale Entropy Algorithm

Entropy ◽

10.3390/e23060659 ◽

2021 ◽

Vol 23 (6) ◽

pp. 659

Author(s):

Jue Lu ◽

Ze Wang

Keyword(s):

Time Series ◽

Standard Deviation ◽

Coarse Graining ◽

Sample Entropy ◽

Systematic Bias ◽

Original Time Series ◽

Multi Scale ◽

Calculation Results ◽

Surrogate Measure ◽

Original Time

Entropy indicates irregularity or randomness of a dynamic system. Over the decades, entropy calculated at different scales of the system through subsampling or coarse graining has been used as a surrogate measure of system complexity. One popular multi-scale entropy analysis is the multi-scale sample entropy (MSE), which calculates entropy through the sample entropy (SampEn) formula at each time scale. SampEn is defined by the “logarithmic likelihood” that a small section (within a window of a length m) of the data “matches” with other sections will still “match” the others if the section window length increases by one. “Match” is defined by a threshold of r times standard deviation of the entire time series. A problem of current MSE algorithm is that SampEn calculations at different scales are based on the same matching threshold defined by the original time series but data standard deviation actually changes with the subsampling scales. Using a fixed threshold will automatically introduce systematic bias to the calculation results. The purpose of this paper is to mathematically present this systematic bias and to provide methods for correcting it. Our work will help the large MSE user community avoiding introducing the bias to their multi-scale SampEn calculation results.

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Adding low concentrations of clonidine to ropivacaine for transversus abdominis plane blocks does not reduce plasma ropivacaine levels, suggesting a lack of vasoconstrictor effect

Anaesthesia and Intensive Care ◽

10.1177/0310057x19838731 ◽

2019 ◽

Vol 47 (2) ◽

pp. 134-140

Author(s):

Jennifer M Crawford ◽

John A Loadsman ◽

Kenny XF Yang ◽

Peter CA Kam

Keyword(s):

Local Anaesthetics ◽

Transversus Abdominis ◽

Control Group ◽

Transversus Abdominis Plane ◽

Nerve Blocks ◽

Duration Of Action ◽

Low Concentrations ◽

Vasoconstrictor Effect ◽

Surrogate Measure ◽

To Receive

Clonidine has been used successfully to prolong the duration of action of local anaesthetics in peripheral nerve blocks, but its mechanism of action in this setting remains unclear. Some studies suggest that clonidine exerts a vasoconstrictor effect, limiting the washout of local anaesthetic from its site of deposition. We investigated this potential vasoconstrictor effect, using plasma ropivacaine concentrations as a surrogate measure of vasoconstriction, in patients who received transversus abdominis plane (TAP) blocks with and without clonidine. Eighty women undergoing laparoscopic gynaecological surgery were randomly assigned to receive one of four TAP block solutions: 0.2% ropivacaine (control), ropivacaine with clonidine 2 μg/kg (clonidine), ropivacaine with 1:400,000 adrenaline (adrenaline) or ropivacaine and a subcutaneous injection of clonidine 2 μg/kg (SC clonidine). The primary outcome was total venous plasma ropivacaine concentrations up to 6 h after the block. There were no significant differences in plasma ropivacaine concentrations between the control group and the clonidine group at any timepoint in the study, nor were there differences in either the mean maximum ropivacaine concentration ( Cmax) (1.99 μg/mL versus 2.05 μg/mL, P = 0.712) or the time to maximum concentration ( Tmax) (51.0 min versus 56.0 min, P = 0.537). The SC clonidine group also did not differ significantly from the controls ( Cmax 2.13 μg/mL versus 1.99 μg/mL, P = 0.424; Tmax 43.5 min versus 51.0 min, P = 0.201). Plasma ropivacaine concentrations in the adrenaline group were significantly lower than the controls from 10 to 90 min ( P < 0.003 for each comparison), and the Cmax was less than that of the control group (1.36 μg/mL versus 1.99 μg/mL, P < 0.001) with a longer Tmax (103.5 min versus 51.0 min, P = 0.001). These findings indicate that clonidine at a concentration of 1.35 μg/mL added to ropivacaine for TAP blocks did not produce a reduction in plasma ropivacaine concentrations. This suggests a lack of vasoconstrictor effect during TAP blocks. Further studies should evaluate whether vasoconstriction occurs when clonidine is used at higher concentrations or for other blocks.

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Oral Fluoride Levels 1 h after Use of a Sodium Fluoride Rinse: Effect of Sodium Lauryl Sulfate

Caries Research ◽

10.1159/000381192 ◽

2015 ◽

Vol 49 (3) ◽

pp. 291-296 ◽

Cited By ~ 4

Author(s):

Gerald L. Vogel ◽

Gary E. Schumacher ◽

Laurence C. Chow ◽

Livia M.A. Tenuta

Keyword(s):

Sodium Fluoride ◽

Sodium Lauryl Sulfate ◽

Lauryl Sulfate ◽

Fluoride Release ◽

Important Goal ◽

Oral Fluids ◽

Surrogate Measure ◽

Significant Change ◽

Topical Fluoride

Increasing the concentration of free fluoride in oral fluids is an important goal in the use of topical fluoride agents. Although sodium lauryl sulfate (SLS) is a common dentifrice ingredient, the influence of this ion on plaque fluid and salivary fluid fluoride has not been examined. The purpose of this study was to investigate the effect of SLS on these parameters and to examine the effect of this ion on total (or whole) plaque fluoride, an important source of plaque fluid fluoride after a sufficient interval following fluoride administration, and on total salivary fluoride, a parameter often used as a surrogate measure of salivary fluid fluoride. Ten subjects accumulated plaque for 48 h before rinsing with a 12 mmol/l NaF (228 µg/g F) rinse containing or not containing 0.5% (w/w) SLS. SLS had no statistically significant effect on total plaque and total saliva fluoride but significantly increased salivary fluid and plaque fluid fluoride (by 147 and 205%, respectively). These results suggest that the nonfluoride components of topical agents can be manipulated to improve the fluoride release characteristics from oral fluoride reservoirs and that statistically significant change may be observed in plaque fluid and salivary fluid fluoride concentrations that may not be observed in total plaque and total saliva fluoride concentrations.

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