Dual-laser measurement of human stapes footplate motion under blast exposure

AbstractThe dual laser-produced plasma technique for the study of ionic absorption spectra has been developed by the use of two Q-switched ruby lasers to enable independent generation of the absorbing and back-lighting plasmas. Optical pulse handling is used in the coupling cicuits to enable reproducible pulse delays from 250 nsec. to 10 msec, to be achieved. At delay times > 700 nsec. spectra of essentially pure neutral species are observed. The technique is valuable, not only for obtaining the neutral spectra of highly refractory and/or corrosive materials but also for studying behaviour of ionic species as a function of time. Typical spectra are shown in Fig. 1.

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Laser measurement of high-altitude aircraft emissions

10.2514/6.1973-704 ◽

1973 ◽

Author(s):

P. BROCKMAN ◽

R. SEALS, JR.

Keyword(s):

High Altitude ◽

Laser Measurement ◽

Aircraft Emissions

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Faculty Opinions recommendation of Three-dimensional analysis of the vestibular end organs in relation to the stapes footplate and piston placement.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.11261956.12255054 ◽

2011 ◽

Author(s):

Hamid R Djalilian ◽

Hossein Mahboubi

Keyword(s):

Dimensional Analysis ◽

Three Dimensional ◽

Stapes Footplate

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Automatic compensation method for beam drift in long-distance laser measurement

Optics and Precision Engineering ◽

10.37188/ope.20202811.2393 ◽

2020 ◽

Vol 28 (11) ◽

pp. 2393-2402

Author(s):

Bin-he YANG ◽

◽

Yin-di CAI ◽

Zhi-xiang WEN ◽

Si-ying LING

Keyword(s):

Compensation Method ◽

Laser Measurement ◽

Automatic Compensation ◽

Long Distance

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A-126 Clinical Utility of Risk Factors to Predict Self-reported Neurobehavioral Outcome Following Traumatic Brain Injury: PTSD, Sleep, Resilience, and Lifetime Blast Exposure

Archives of Clinical Neuropsychology ◽

10.1093/arclin/acaa068.126 ◽

2020 ◽

Vol 35 (6) ◽

pp. 919-919

Author(s):

Lange R ◽

Lippa S ◽

Hungerford L ◽

Bailie J ◽

French L ◽

...

Keyword(s):

Risk Factors ◽

Traumatic Brain Injury ◽

Risk Factor ◽

Brain Injury ◽

Clinical Utility ◽

Poor Sleep ◽

Post Injury ◽

Poor Outcome ◽

Blast Exposure ◽

Neurobehavioral Outcome

Abstract Objective To examine the clinical utility of PTSD, Sleep, Resilience, and Lifetime Blast Exposure as ‘Risk Factors’ for predicting poor neurobehavioral outcome following traumatic brain injury (TBI). Methods Participants were 993 service members/veterans evaluated following an uncomplicated mild TBI (MTBI), moderate–severe TBI (ModSevTBI), or injury without TBI (Injured Controls; IC); divided into three cohorts: (1) < 12 months post-injury, n = 237 [107 MTBI, 71 ModSevTBI, 59 IC]; (2) 3-years post-injury, n = 370 [162 MTBI, 80 ModSevTBI, 128 IC]; and (3) 10-years post-injury, n = 386 [182 MTBI, 85 ModSevTBI, 119 IC]. Participants completed a 2-hour neurobehavioral test battery. Odds Ratios (OR) were calculated to determine whether the ‘Risk Factors’ could predict ‘Poor Outcome’ in each cohort separately. Sixteen Risk Factors were examined using all possible combinations of the four risk factor variables. Poor Outcome was defined as three or more low scores (< 1SD) on five TBI-QOL scales (e.g., Fatigue, Depression). Results In all cohorts, the vast majority of risk factor combinations resulted in ORs that were ‘clinically meaningful’ (ORs > 3.00; range = 3.15 to 32.63, all p’s < .001). Risk factor combinations with the highest ORs in each cohort were PTSD (Cohort 1 & 2, ORs = 17.76 and 25.31), PTSD+Sleep (Cohort 1 & 2, ORs = 18.44 and 21.18), PTSD+Sleep+Resilience (Cohort 1, 2, & 3, ORs = 13.56, 14.04, and 20.08), Resilience (Cohort 3, OR = 32.63), and PTSD+Resilience (Cohort 3, OR = 24.74). Conclusions Singularly, or in combination, PTSD, Poor Sleep, and Low Resilience were strong predictors of poor outcome following TBI of all severities and injury without TBI. These variables may be valuable risk factors for targeted early interventions following injury.

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Repeated Occupational Exposure to Low-level Blast in the Canadian Armed Forces: Effects on Hearing, Balance, and Ataxia

Military Medicine ◽

10.1093/milmed/usaa439 ◽

2021 ◽

Author(s):

Ann Nakashima ◽

Oshin Vartanian ◽

Shawn G Rhind ◽

Kristen King ◽

Catherine Tenn ◽

...

Keyword(s):

Hearing Loss ◽

Occupational Exposure ◽

Armed Forces ◽

Cross Sectional ◽

Low Level ◽

Additional Information ◽

Adverse Health Effects ◽

Blast Overpressure ◽

Blast Exposure

ABSTRACT Introduction Recently, there has been increasing concern about the adverse health effects of long-term occupational exposure to low-level blast in military personnel. Occupational blast exposure occurs routinely in garrison through use of armaments and controlled blast detonations. In the current study, we focused on a population of breaching instructors and range staff. Breaching is a tactical technique that is used to gain entry into closed spaces, often through the use of explosives. Materials and Methods Initial measurements of blast overpressure collected during breaching courses found that up to 10% of the blasts for range staff and up to 32% of the blasts for instructors exceeded the recommended 3 psi exposure limit. Using a cross-sectional design, we used tests of balance, ataxia, and hearing to compare a sample of breachers (n = 19) to age-and sex-matched military controls (n = 19). Results There were no significant differences between the two groups on the balance and ataxia tests, although the average scores of both groups were lower than would be expected in a normative population. The prevalence of hearing loss was low in the breacher group (4 of 19), and hearing thresholds were not significantly different from the controls. However, the prevalence of self-reported tinnitus was significantly higher in the breacher group (12 of 19) compared with the controls (4 of 19), and all breachers who were identified as having hearing loss also reported tinnitus. Conclusions Our results suggest that basic tests of balance, ataxia, and hearing on their own were not sensitive to the effects of long-term occupational exposure to low-level blast. Some of the blast exposure levels exceeded limits, and there was a significant association of exposure with tinnitus. Future studies should supplement with additional information including exposure history and functional hearing assessments. These findings should be considered in the design of future acute and longitudinal studies of low-level blast exposure.

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