An Evaluation of the Quality of CPR Chest Compressions Performed on Football-Equipped and Obese Simulation Manikins.

OBJECTIVE: Protective athletic equipment may hamper the delivery of effective chest compressions. Unfortunately, an algorithm for managing cardiac arrest emergencies with equipment-laden athletes has yet to be established by national CPR certifying agencies. Further, athletes classified as being overweight or obese carry adipose in the thoracic region, which has been reported to inhibit the ability of rescuers to provide quality chest compressions. Thus, the purpose of this study was two-fold. The first purpose was to assess the ability of emergency responders to perform CPR chest compressions on an obese manikin. The second purpose was to analyze the effect of American football protective equipment on the performance of chest compressions by emergency responders. METHODS: Fifty emergency responders completed four 2-minute bouts of compression-only CPR. The scenarios included performing chest compressions on both traditional and obese CPR manikins, and performing chest compressions over a set of shoulder pads/chest protector that is used in the sport of American football on both traditional and obese manikins. RESULTS: The most notable outcomes in this study were related to chest compression depth, which fell well below the minimum recommended depth published by the American Heart Association in all conditions. Mean compression depth was significantly lower when performed on the obese manikin (avg over pads = 32.8, SD = 9.2 mm; avg no pads = 38.2, SD = 9.1 mm) compared to the traditional manikin (avg over pads = 40.0, SD = 10.9 mm; avg no pads = 40.8, SD = 14.8 mm), with statistical analyses revealing a significant effect due to both manikin size (p < 0.001) and the presence of equipment (p = 0.003), and a statistically significant interaction effect (p = 0.035). Chest recoil data revealed a statistically significant effect due to both manikin size (p = 0.017) and the presence of chest/shoulder safety pads (p = 0.003). CONCLUSION: Within this sample of emergency responders, chest compressions were adversely affected both by the equipment and obesity. Additionally, the traditional manikin received comparable chest compressions regardless of the presence or absence of football protective equipment, albeit both conditions resulted in poor depth performance.

Experimental Investigation on Hardware and Triggering Effect in Tip-Timing Measurement Uncertainty.

Non-destructive testing for structural health monitoring is becoming progressively important for gas turbine manufacturers. As several techniques for diagnostics and condition-based maintenance have been developed over the years, the tip-timing approach is one of the preferred approaches for characterizing the dynamic behavior of turbine blades using non-contact probes. This experimental work investigates the uncertainty of the time-of-arrival of a Blade Tip-Timing measurement system, a fundamental requirement for numerical and aeromechanical modeling validation. The study is applied to both the measurement setup and the data processing procedure of a generic commercial measurement system. The influence of electronic components and signal processing on the tip-timing uncertainty is determined under different operating conditions.

State-Space Model for Arrival Time Simulations and Methodology for Offline Blade Tip-Timing Software Characterization.

Blade tip-timing is an extensively used technique for measuring blade vibrations in turbine and compressor stages; it is one of the preferred techniques used for characterizing their dynamic behaviors using non-contact probes. Typically, arrival time signals are acquired and processed by a dedicated measurement system. Performing a sensitivity analysis on the data processing parameters is essential for the proper design of tip-timing test campaigns. This study proposes a mathematical model for generating synthetic tip-timing signals, descriptive of specific test conditions. The generated signals were used as the controlled input for a thorough characterization of post-processing software for tip-timing analysis. This work represents the first step in quantifying the uncertainty introduced by tip-timing analysis software into user measurements. The proposed methodology can also offer essential information for further sensitivity studies on parameters that influence the accuracy of data analysis during testing.

Examination of Near Point of Convergence Scores in High-School Athletes: Implications for Identifying Binocular Vision Dysfunction After Concussion Injury.

OBJECTIVE: To identify normative near point of convergence (NPC) data for healthy high-school-aged athletes (13-19 years old) and determine the percentage of individuals with NPC scores that fall outside the currently accepted clinical cutoff value of 5 cm. Another objective was to determine the relationship between sex, concussion history, and attention deficit disorder/attention deficit hyperactivity disorder (ADD/ADHD) with NPC scores, if any. DESIGN: Case series. SETTING: High-school sports medicine clinic. PATIENTS OR PARTICIPANTS: Near point of convergence was assessed in 718 high-school student athletes (141 females and 577 males) with an average age of 15.96 ± 1.16 years. INTERVENTIONS: None. MAIN OUTCOME MEASURES: An accommodation convergence ruler was used to measure NPC. Near point of convergence scores were repeated a total of 3 times and the mean used for all statistical analyses. RESULTS: The NPC scores for all participants averaged 3.58 cm, and the intraclass correlation coefficient for the 3 repeated measurements was 0.956. Approximately 20% of mean NPC scores were above the accepted upper limit of 5 cm. Although a statistically significant effect for sex was identified, the difference between them was considered clinically insignificant. No relationship between NPC and history of concussion or ADD/ADHD was identified. CONCLUSIONS: Results indicate that in high-school-aged subjects, approximately 20% of individuals may have NPC values that fall outside the current critical cutoff value and may lead to incorrect diagnosis of ocular dysfunction. In addition, NPC does not seem to be affected by the history of concussion or a diagnosis of ADD/ADHD.

Predicting Concussion Recovery with PHQ-9 and GAD-7.

OBJECTIVE: To determine whether scores obtained from Patient Health Questionnaire-9 (PHQ-9) or the General Anxiety Disorder-7 (GAD-7) instruments administered following a concussion can be used to predict recovery time. METHOD: Retrospective cohort study in a university-based specialty concussion center of 502 concussed participants. Participants completed a PHQ-9 and GAD-7 during their initial visit and subsequent visits during the recovery period (ie, at 14, 28, 56, and 84 days). RESULTS: The median recovery time from a concussion was 21 days from the initial clinical evaluation; however, individuals with a PHQ-9 score ≤ 6 (n = 262) had a median recovery time of 17 (95% confidence interval [CI] 15-19) days, whereas those with PHQ-9 scores >6 (n = 240) had a median recovery time of 33 (95% CI 28-37) days and a hazard ratio of 0.525 (95% CI 0.438-0.629, P < 0.0001). For individuals with a GAD-7 score ≤ 4 (n = 259), the median recovery was 19 (95% CI 17-21), days whereas for those with a GAD-7 score > 4 (n = 243), the median recovery was 32 (95% CI 28-36) days with a hazard ratio of 0.554 (95% CI 0.462-0.664, P < 0.00). CONCLUSIONS: Scores obtained from PHQ-9 and GAD-7 screening tools appear to be predictive of an individual's recovery and may help identify those subjects who may benefit from early psychological interventions.

Vestibular Schwannoma Resection with Ipsilateral Simultaneous Cochlear Implantation in Patients with Normal Contralateral Hearing.

OBJECTIVE: To report the hearing results of cochlear implantation simultaneous to vestibular schwannoma (VS) resection by means of a translabyrinthine approach in patients with normal contralateral hearing. METHODS: This was a prospective study including adults with sporadic VS. Tumors were resected by means of a modified translabyrinthine approach with preservation of the cochlear nerve. RESULTS: A total of 13 patients underwent cochlear implantation. At 14 months, the mean pure-tone audiogram was 56 dB. The mean speech recognition was 80%. Cochlear implantation provides monaural and binaural benefits in all the conditions tested, including sound localization. CONCLUSIONS: Cochlear implantation can be safely performed simultaneously to VS resection with satisfactory hearing results provided that the cochlear nerve is anatomically intact.

Motion produced in the unstable cervical spine by the HAINES and lateral recovery positions.

STUDY OBJECTIVE: To compare the amount of segmental vertebral motion produced with the lateral recovery position and the HAINES technique when performed on cadavers with destabilized cervical spines. METHODS: The cervical spines of 10 cadavers were surgically destabilized at the C5-C6 vertebral segment. Sensors from an electromagnetic tracking device were affixed to the vertebrae in question to monitor the amount of anterior/posterior, medial/lateral, and distraction/compression linear motion produced during the application of the two study techniques. RESULTS: The statistical analysis of linear motion data did not reveal any significant differences between the two recovery positions. CONCLUSION: At this time, no single version of the recovery position can be endorsed for the spine-injured trauma patient. More research is needed to fully ascertain the safety of commonly used recovery positions.

Student Debt Associated with Entry-level Athletic Training Education.

CONTEXT: Borrowers burdened by high student debt generally experience financial constraints that can impact them both personally and professionally. To date no published data exists that profiles the education-related debt accrued by entry-level certified athletic trainers. OBJECTIVE: To assess the scope and scale of student debt associated with the completion of an entry-level athletic training degree. DESIGN: Cross-sectional study. SETTING: Online web-based survey. PATIENTS OR OTHER PARTICIPANTS: Participants were recruited with assistance from the National Athletic Trainers' Association, who disseminated the survey to 18,689 certified athletic trainers who were members in good standing and who had earned their certification between 2004 and 2022. A total of 2,271 individuals accessed the survey. MAIN OUTCOME MEASURE(S): The overall amount of student debt incurred to complete an entry-level degree in athletic training and the initial monthly repayment amount were collected from survey respondents. Education-related debt-to-income ratio (DTIR) and monthly payment DTIR which are measures of financial health/stability were also calculated from the acquired survey data. RESULTS: Among athletic trainers who took out student loans, the average amount owed by entry-level athletic trainers for the period spanning 20042022 was $61,717, with an average initial monthly loan payment amount reported to be $453. The mean education related DTIR calculated from respondents was 169%, which exceeded the benchmark value of 100% recommended within the finance industry. Also, the average monthly payment DTIR calculated from study participants was .144, which approached the recommended acceptable upper-limit of .15. CONCLUSIONS: Education-related DTIR and monthly payment DTIR values reported by respondents suggests the potential for entry-level athletic trainers to experience financial challenges related to their student debt.

Motion is reduced in the unstable spine with the use of mechanical devices for bed transfers.

CONTEXT: Excessive spinal motion generated during multiple bed transfers of patients with unstable spine injuries may contribute to neurological deterioration. OBJECTIVE: To evaluate spinal motion in a cadaveric model of global spinal instability during hospital bed transfers using several commonly used techniques. DESIGN/PARTICIPANTS: A motion analysis and evaluation of hospital bed transfer techniques in a cadaveric model of C5-C6 and T12-L2 global spinal instability. Setting/outcome measures: Global instability at C5-C6 and T12-L2 was created. The motion in three planes was measured in both the cervical and lumbar spine during each bed transfer via electromagnetic motion detection devices. Comparisons between transfers performed using an air-assisted lateral transfer device, manual transfer, a rolling board, and a sliding board were made based on the maximum range of motion observed. RESULTS: Significantly less lateral bending at C5-C6 was observed in air-assisted device transfers when compared with the two other boards. Air-assisted device transfers produced significantly less axial rotation at T12-L2 than the rolling board, and manual transfers produced significantly less thoracolumbar rotation than both the rolling and sliding boards. No other significant differences were observed in cervical or lumbar motion. Motion versus time plots indicated that the log roll maneuvers performed during rolling board and sliding board transfers contributed most of the observed motion. CONCLUSIONS: Each transfer technique produced substantial motion. Transfer techniques that do not include the logroll maneuver can significantly decrease some components of cervical and lumbar motion. Thus, some spinal motion can be reduced through selection of transfer technique.

Is sub-occipital padding necessary to maintain optimal alignment of the unstable spine in the prehospital setting? A preliminary report.

BACKGROUND: As prehospital emergency rescuers prepare cervical spine-injured adult patients for immobilization and transport to hospital, it is essential that patients be placed in a favorable position. Previously, it was recommended that patients with cervical spine injuries be immobilized in a slightly flexed position using pads placed beneath the head. However, it is unknown how neck flexion created with pad placement affects the unstable spine. OBJECTIVE: To determine the effects of three different head positions on the alignment of unstable vertebral segments. METHODS: Five cadavers with a complete segmental instability at the C5 and C6 level were included in the study. The head was either placed directly on the ground (or spine board) or on foam pads. Three conditions were tested: no pad; pads 2.84 cm thick; and pads 4.26 cm thick. Pads were positioned beneath the head to determine their effect on spinal alignment. Anterior-posterior translation, flexion-extension motion, and axial displacement across the unstable segment were compared between conditions. RESULTS: Although statistical tests failed to identify any significant differences between pad conditions, some meaningful results were noted. In general, the "no pad" condition aligned the spine in a position that best replicated the intact spine. CONCLUSIONS: Because the goal of emergency rescuers is to conserve whatever physiologic or structural integrity of the spinal cord and spinal column that remains, the outcome of this study suggests that this goal may be best achieved using the "no pad" condition. However, it is recommended that more research be conducted to confirm these preliminary findings.

Stimulant Therapy Utilization for Neurocognitive Deficits in Mild Traumatic Brain Injury.

CONTEXT: There are 3.8 million mild traumatic brain injuries (mTBIs) that occur each year in the United States. Many are left with prolonged life-altering neurocognitive deficits, including difficulties in attention, concentration, mental fatigue, and distractibility. With extensive data on the safety and efficacy of stimulant medications in treating attention deficit, concentration difficulties and distractibility seen with attention deficit disorder, it is not surprising that interest continues regarding the application of stimulant medications for the persistent neurocognitive deficits in some mTBIs. EVIDENCE ACQUISITION: Studies were extracted from PubMed based on the topics of neurocognitive impairment, mTBI, stimulant use in mTBI, stimulants, and the association between attention deficit/hyperactivity disorder and mTBI. The search criteria included a date range of 1999 to 2020 in the English language. STUDY DESIGN: Literature review. LEVEL OF EVIDENCE: Level 4. RESULTS: Currently, there is very limited literature, and no guidelines for evaluating the use of stimulant medication for the treatment of prolonged neurocognitive impairments due to mTBI. However, a limited number of studies have demonstrated efficacy and safety of stimulants in the treatment of neurocognitive sequelae of mTBI in the adult, pediatric, military, and athletic populations. CONCLUSION: There is limited evidence to suggest stimulant medication may be beneficial in patients with mTBI with persistent neurocognitive symtpoms. The decision to utilize stimulant medication for mTBI patients remains physician and patient preference dependent. Given the limited encouraging data currently available, physicians may consider stimulant medication in appropriate patients to facilitate the recovery of prolonged neurocognitive deficits, while remaining cognizant of potential adverse effects.

Removing a patient from the spine board: is the lift and slide safer than the log roll?

BACKGROUND: After spine board immobilization of the trauma victim and transport to the hospital, the patient is removed from the spine board as soon as practical. Current Advanced Trauma Life Support's recommendations are to log roll the patient 90 degrees, remove the spine board, inspect and palpate the back, and then log roll back to supine position. There are several publications showing unacceptable motion in an unstable spine when log rolling. METHODS: Cervical spine motion was evaluated during spine board removal. A C5 to C6 instability was surgically created in cadavers. A three-dimensional electromagnetic tracking system was used to assess motion between C5 and C6. The log roll was compared with a lift-and-slide technique. Throughout the log roll procedure, manual inline cervical stabilization was provided by a trained individual in a series of trials. In other trials, the lift-and-slide technique was used. In the final stage, the amount of motion generated was assessed when the spine board removal techniques were completed by experienced and novice persons in maintaining inline stabilization of the head and neck. RESULTS: Motion between C5 and C6 was reduced during the lift-and-slide technique in five of six parameters. The reduction was statistically significant in four parameters. When performing the log roll, motion was not reduced with increased head holder experience. CONCLUSIONS: Spine boards can be removed using a lift-and-slide maneuver with less motion and potentially less risk to the patient's long-term neurologic function than expected using the log roll.

Bio-mechanical characterization of a CAD/CAM PMMA resin for digital removable prostheses.

OBJECTIVE: To compare the mechanical and biological features of a polymethylmethacrylate (PMMA) disc for CAD/CAM prostheses (test samples, TG) with a traditional resin (control samples, CG). METHODS: Mechanical analysis was performed using Dynamic Mechanical Analysis (DMA) and Brillouin's micro-spectroscopy. Human keratinocyte morphology and adhesion were analyzed by scanning electronic microscopy (SEM), cytotoxicity by the MTT assay, apoptosis by flow cytometry and p53, p21 and bcl2 gene expression by real time PCR. RESULTS: TG exhibited a higher elastic modulus than CG (range 5100-5500 ± 114.3 MPa vs 3000-3300 ± 99.97 MPa). The Brillouin frequency was found at ωB= (15.50 ± 0.05) GHz for TG and at ωB_1 = (15.50 ± 0.05) GHz and ωB_2 = (15.0 ± 0.1) GHz for CG where two peaks were always present independently of the sample point. SEM analysis revealed that keratinocytes on TG disks appeared to be flattened with lamellipodia. Keratinocytes on CG disks rose above the substrate with cytoplasmatic filaments. MTT viability data at 3 h and 24 h showed TG was significantly less cytotoxic than CG (p < 0.001). No significant differences emerged in apoptosis on CG and TG. Real-time PCR showed p53 expression increased after 3 h by about 9-fold in keratinocytes on TG (p < 0.001) and about 5-fold in those on CG (p < 0.001). High p53 expression persisted after 24 h on both disks. No significant variations were observed in p21 and bcl2 expression at any time-point. SIGNIFICANCE: PMMA resins, as used in CAD/CAM technology, displayed suitable biocompatible and mechanical properties for removable prostheses.

Are scoop stretchers suitable for use on spine-injured patients?

INTRODUCTION: In the prehospital setting, spine-injured patients must be transferred to a spine board to immobilize the spine. This can be accomplished using both manual techniques and mechanical devices. OBJECTIVES: The study aimed to evaluate the effectiveness of the scoop stretcher to limit cervical spine motion as compared to 2 commonly used manual transfer techniques. METHODS: Three-dimensional angular motion generated across the C5-C6 spinal segment during execution of 2 manual transfer techniques and the application of a scoop stretcher was recorded first on cadavers with intact spines and then repeated after C5-C6 destabilization. A 3-dimensional electromagnetic tracking device was used to measure the maximum angular and linear motion produced during all test sessions. RESULTS: Although not statistically significant, the execution of the log roll maneuver created more motion in all directions than either the lift-and-slide technique or with scoop stretcher application. The scoop stretcher and lift-and-slide techniques were able to restrict motion to a comparable degree. CONCLUSION: The effectiveness of the scoop stretcher to limit spinal motion in the destabilized spine is comparable or better than manual techniques currently being used by primary responders.

Early Aerobic Exercise for the Treatment of Acute Pediatric Concussions.

Sport-related concussion is a common injury that has garnered the attention of the media and general public because of the potential for prolonged acute symptoms and increased risk for long-term impairment. Currently, a growing body of evidence supports the use of various therapies to improve recovery after a concussion. A contemporary approach to managing concussion symptoms is to use aerobic exercise as treatment. To date, several studies on both pediatric and adult patients have established that controlled aerobic exercise is a safe and effective way to rehabilitate patients experiencing delayed recovery after concussion. However, less is known about the utility of an early exercise protocol for optimizing recovery after acute concussion and reducing the risk for persistent postconcussive symptoms, particularly in pediatric populations. Thus, the purpose of our paper was to review and evaluate the available literature on the implementation of aerobic exercise for the treatment of acute pediatric concussion.

Optimal frequency, displacement, duration, and recovery patterns to maximize power output following acute whole-body vibration.

Power is an important component of general health, fitness, and athletic performance. Traditional overload techniques require considerable time, intensity, and volume of training. Whole-body vibration (WBV) is a potentially less time-consuming method for increasing power performance than traditional training. However, the exact protocols that can maximize power output have not yet been identified. Eleven healthy men, aged 32.3 +/- 4.1 years, and 9 healthy women, aged 29.1 +/- 3.5 years, performed countermovement jumps (CMJs) of maximal volition to assess peak power pre and post (immediately and at 1, 5, and 10 minutes) randomized WBV stimuli set at different frequency (30, 35, 40, and 50 Hz), displacement (2-4 vs. 4-6 mm), and duration (30, 45, and 60 seconds) combinations. Repeated-measures analysis of variance on peak power normalized to initial power (nPP) revealed no significant effects attributable to duration of stimulus. However, high frequencies were more effective when combined with high displacements, and low frequencies were more effective in conjunction with low displacements (p < 0.05). Additionally, the greatest improvements in nPP occurred at 1 minute posttreatment, with significant improvements lasting through 5 minutes posttreatment (p < 0.05). Optimal acute effects can be attained using as little as 30 seconds of WBV, and they are highest from 1 to 5 minutes posttreatment. Additionally, high frequencies were most effective when applied in conjunction with high displacements, whereas low frequencies were most effective when applied in conjunction with low displacements.

Fabricating a better mouthguard. Part II: the effect of color on adaptation and fit.

The thermoforming process involves the heating of plastic sheets to a critical temperature followed by the shaping of the heated material into a three-dimensional structure. Given that custom-fabricated mouthguards are produced using the thermoforming process, the adaptation of plastic sheets to a stone model of the dentition is likely to be affected by the ability of the mouthguard material to be heated. The purpose of this study was to establish if material color affected the adaptation and fit of custom-made mouthguards. Twelve stone models were used in this investigation. Five mouthguards were produced using each model. These mouthguards were made using clear-, white-, black-, blue- and green-colored ethyl vinyl acetate. The force required to remove the various colored mouthguards from the corresponding stone models was determined using a strain gauge housed within a specially designed apparatus. Each of the mouthguards were tested three times at two different angles of pull -45 degrees and 90 degrees . Statistical tests performed using the average amount of force required for mouthguard removal revealed an angle by color interaction. Post hoc analyses revealed that the mean force required to remove the clear-colored mouthguards from their respective stone models was significantly less than the force required to pull away blue-, black- and green-colored mouthguards. This difference between clear- and dark-colored mouthguards was observed at both angles tested with the exception of the black mouthguard which differed from the clear-colored mouthguard only when removed at an angle of 90 degrees . The results of the present study indicate that by using dark-colored mouthguard material, one can achieve superior adaptation and thus produce a more firmly fitting mouthguard.

Cochlear Implantation in Cochlear Ossification: Retrospective Review of Etiologies, Surgical Considerations, and Auditory Outcomes.

OBJECTIVES: 1) To review the surgical and auditory outcomes and complications of cochlear implantation in cases with cochlear ossification. 2) To evaluate association between the extent and etiology of ossification to outcomes. STUDY DESIGN: Retrospective study. SETTING: Otology and skull base surgery center. SUBJECTS AND METHODS: Charts of 40 patients (42 ears) with cochlear ossification undergoing cochlear implantation were reviewed. Demographic features, operative findings, auditory outcomes, and complications were analyzed. Operative findings included extent of cochlear ossification, extent of drilling required to obtain patent cochlear lumen, approach (posterior tympanotomy/subtotal petrosectomy), electrode insertion (partial/complete, scala tympani/vestibuli), and complications. Auditory outcomes were assessed over a 4-year follow-up period using vowel, word, sentence, and comprehension scores. Patients were divided into groups (otosclerotic/non-otosclerotic and round window/basal turn ossification) for comparison of auditory outcomes. Outcomes were compared with 60 randomly identified controls (adults with postlingual deafness) who underwent implantation with no cochlear ossification. RESULTS: The median age and duration of deafness of patients was 54.39 and 27.15 years, respectively. Etiology of cochlear ossification was otosclerosis in 23 of 42 ears and mixed in 19 of 42 ears (chronic otitis media, temporal bone fractures, idiopathic, meningitis, Cogan's syndrome) with exclusive round window involvement in 54.7% of cases and the rest having partial or complete basal turn ossification. 59.5% ears underwent subtotal petrosectomy for implantation. Three patients underwent scala vestibuli insertion and five had incomplete electrode insertion. Auditory outcomes were comparable in otosclerotic and non-otosclerotic cases and in round window and basal turn ossification cases. No significant differences were observed in auditory scores when compared with controls with no ossification. CONCLUSIONS: Cochlear implantation in cochlear ossification is feasible despite surgical challenges and modifications. Auditory outcomes in basal turn ossification appear to be comparable to cases with no ossification with extent of ossification having no significant association with outcomes.

Evaluating the Recovery Curve for Clinically Assessed Reaction Time After Concussion.

CONTEXT: A change in reaction time is one of various clinical measures of neurocognitive function that can be monitored after concussion and has been reported to be among the most sensitive indicators of cognitive impairment. OBJECTIVE: To determine the timeline for clinically assessed simple reaction time to return to baseline after a concussion in high school athletes. DESIGN: Observational study. SETTING: Athletic training room. PATIENTS OR OTHER PARTICIPANTS: Twenty-one high school-aged volunteers. INTERVENTION(S): Participants completed 8 trials of the ruler-drop test during each session. Along with baseline measures, a total of 6 additional test sessions were completed over the course of 4 weeks after a concussion (days 3, 7, 10, 14, 21, and 28). MAIN OUTCOME MEASURE(S): The mean reaction times calculated for all participants from each of the 7 test sessions were analyzed to assess the change in reaction time over the 7 time intervals. RESULTS: After a concussion and compared with baseline, simple reaction time was, on average, 26 milliseconds slower at 48 to 72 hours postinjury (P < .001), almost 18 milliseconds slower on day 7 (P < .001), and about 9 milliseconds slower on day 10 (P < .001). Simple reaction time did not return to baseline levels until day 14 postinjury. CONCLUSIONS: Clinically assessed simple reaction time appeared to return to baseline levels within a timeframe that mirrors other measures of cognitive performance (approximately 14 days).

Fibre Bragg Gratings for the Monitoring of Wooden Structures.

The aim of this work was to develop and validate an experimental methodology suitable for analysing on-site the behaviour of fibre-reinforced wooden structures. The proposed measurement method is based on the application of fibre Bragg grating (FBG) strain sensors. An analysis of adhesive behaviour was performed preliminarily, which provided indications for choosing the type of adhesive and for the fibre bonding length in accordance with the volume of measurement. The first series of tests was carried out on wood samples to verify the coupling between the measuring sensor and the wood support when the latter is subject to mechanical stresses. The second investigation was done on site to test the behaviour of a historical wood floor before and after reinforcement by means of a series of tests performed using optical fibres with the Bragg grating. The optical fibre system measurements were compared to those obtained using a laser vibrometer, a measurement system of proven stability and precision. The comparison makes it possible to confirm the validity of the results and the reliability of the system for the monitoring of historic wooden structures.