Evaluation of the effectiveness of non-contact respiration rate detection for post-crash care application

The ability of emergency medical services (EMS) personnel to understand the mortality and morbidity risks associated with different injuries is critical for effective motor vehicle collision (MVC) post-crash care. Interwoven with this ability is the practice of accurate and efficient patient triage. Triage allows EMS to gain a better understanding of the physiological and physical status of a patient and their injuries, with the intention of identifying additional resources needed, potential treatment options, and the most appropriate care destination. An interactive, in-vehicle triage system, based on the Simple Triage and Rapid Treatment protocol, under development could lead to improved MVC triage accuracy and efficiency. As a component of that system, this study examines the effectiveness of using non-contact respiration rate detection technologies integrated into a vehicle cabin. The selected technologies included ultrasonic respiration detection, thermal respiration detection, and pressurebased detection which were all compared against data collected from a respiration belt. All technologies were integrated into a 2015 Ford Taurus. Testing took place inside the running vehicle and considered occupant weight, cabin temperature, occupant clothing weight, and environmental sound as experimental factors. Respiration rate was then calculated using a 30-second sliding window where the means and standard deviations were used to compare the accuracy and precision of the sensor systems across the experimental factors. The sensor type, temperature level, and sound level main effects significantly influenced the mean respiration rate. For the standard deviation of respiration rate, significant effects were found for the sensor type, sound level, and clothing weight main effects. Among the tested sensor systems, the pressure sensor was found to best match the accuracy and precision of the respiration belt. Future work should address limitations in the approach used for this proof-of-concept work.

Differences in frequency of occurrence, event characteristics, and pre-impact vehicle kinematics between crashes, near-crashes, and single vehicle conflicts in a large-scale naturalistic driving study

Objective: Motor vehicle crashes result in egregious personal injury, mortality, and economic cost but are relatively rare in naturalistic observations. There is, however, evidence of strong relationships between crashes and less severe (but more common) "surrogate" events (e.g., near-crashes). Despite this strong relationship, there can still be some important differences in findings when these surrogate events are investigated in lieu of, or combined with, crashes. Therefore, it is relevant to describe and quantify differences between crashes and crash-surrogate events. Consequently, the focus of this investigation was to establish how crashes and crash surrogate events in a large-scale naturalistic driving study compare in terms of frequency of occurrence, event characteristics, and pre-impact vehicle kinematics.Methods: Crashes, near-crashes, and single-vehicle conflicts (SVCs) derived from the Second Strategic Highway Research Program Naturalistic Driving Study were coded to summarize the environmental and contributing variables involved. The original coding for these events was downsized to the variables of interest, and those variables underwent recoding to simplify the coded options. Additional variables based on the kinematic characteristics for each event were also derived and analyzed. Multinomial logistic regression was used to assess the contributions of these different variables toward classification of an event as a crash, near-crash, or SVC.Results: The regression model comparing crashes with near-crashes and SVCs identified several variables that allowed differentiation between crashes and these surrogates, primarily the pre-incident maneuver of the subject vehicle and the evasive maneuver that was executed by the driver. Kinematic variables prior to event onset, however, were not predictive of event outcome.Conclusions: The results suggest that important differences exist between crashes and their near-crash surrogates, and between crashes and SVCs. These results, however, should not discourage the analysis of surrogate events, which still provide useful information in prevention and mitigation of crash circumstances. This investigation highlights how crashes are different from two types of surrogate events and provides information that may allow for more precise analysis of these surrogate events in the future.

Patient-Reported Symptoms in the Global Multiple System Atrophy Registry

Background

The Global Multiple System Atrophy Registry (GLOMSAR) was established in 2013. It is an online patient-reported contact registry open and free that relies on self-reported diagnosis by the patient or caregiver.

Objectives

To report the demographics of patients enrolled in GLOMSAR and the results of an ancillary online symptom questionnaire.

Methods

Patients enrolled in GLOMSAR were invited to complete a custom-designed online questionnaire about disease onset and symptom prevalence.

Results

At the time of writing, there were 1083 participants in GLOMSAR, of which 33% (365) completed the questionnaire. The onset and frequency of most symptoms was similar to those reported in the literature in physician-reported studies. Some were understudied or not typically associated with multiple system atrophy (MSA), including reduced female sexual sensation (55%), forgetfulness (60%), pseudobulbar affect (37%), olfactory changes (36%), and visual hallucinations (21%).

Conclusions

Patient-reported studies and ancillary online questionnaires are valid, underused research tools useful to advance our knowledge on understudied MSA features and highlight the patients' voice.

Patients Who Undergo Rotator Cuff Repair Can Safely Return to Driving at 2 Weeks Postoperatively

BACKGROUND

Evidence-based guidelines are lacking for return to driving following rotator cuff repair (RCR). As a result, surgeons are often overly conservative in their recommendations, placing potential undue burden on patients and their families. Therefore, the primary objective of this study was to formulate evidence-based return-to-driving guidelines.

METHODS

Thirty-two subjects planning to undergo primary RCR were enrolled. Driving fitness was assessed in a naturalistic setting with an instrumented vehicle on public streets with a safety monitor onboard. Driving kinematic measures and behavioral data were obtained from vehicle data and camera capture. Several driving tasks and maneuvers were evaluated, including parking, left and right turns, straightaways, yielding, highway merges, and U-turns. The total course length was 15 miles (24 km) and the course took 45 to 55 minutes to complete. The subjects' baseline drive was performed prior to RCR and postoperative drives occurred at 2, 4, 6, and 12 weeks after RCR. All drives consisted of identical routes, tasks, and maneuvers. Driving metrics were analyzed for differences between baseline and postoperative drives, including differences in gravitational force equivalents (g).

RESULTS

Twenty-seven subjects (mean age, 58.6 years [range, 43 to 68 years]) completed all 5 drives. Of the 13 analyzed kinematic metrics measured from 14 of 17 driving events, all exhibited noninferiority across all postoperative drives (2 to 12 weeks) after RCR compared with baseline. Beginning at postoperative week 2, subjects generally braked less aggressively, steered more smoothly, and drove more stably. Kinematic metrics during the performance of specific maneuver types also showed noninferiority when compared with baseline. Of note, subjects drove more smoothly on highway merges starting at postoperative week 2 (minimum longitudinal acceleration, -0.35 g [95% confidence interval (CI), -0.050 to -0.019 g]; standard deviation of longitudinal acceleration, 0.008 g [95% CI, 0.003 to 0.013 g]), but exhibited more aggressive driving and acceleration on highway merges at postoperative week 12 (maximum absolute yaw, -0.8°/sec [95% CI, -1.2°/sec to -0.4°/sec]).

CONCLUSIONS

Patients showed no clinically important negative impact on driving fitness as early as 2 weeks after RCR. Adaptive behaviors were present both preoperatively and postoperatively.

LEVEL OF EVIDENCE

Prognostic Level II . See Instructions for Authors for a complete description of levels of evidence.

mTOR Inhibition with Sirolimus in Multiple System Atrophy: A Randomized, Double-Blind, Placebo-Controlled Futility Trial and 1-Year Biomarker Longitudinal Analysis

BACKGROUND

Multiple system atrophy (MSA) is a fatal neurodegenerative disease characterized by the aggregation of α-synuclein in glia and neurons. Sirolimus (rapamycin) is an mTOR inhibitor that promotes α-synuclein autophagy and reduces its associated neurotoxicity in preclinical models.

OBJECTIVE

To investigate the efficacy and safety of sirolimus in patients with MSA using a futility design. We also analyzed 1-year biomarker trajectories in the trial participants.

METHODS

Randomized, double-blind, parallel group, placebo-controlled clinical trial at the New York University of patients with probable MSA randomly assigned (3:1) to sirolimus (2-6 mg daily) for 48 weeks or placebo. Primary endpoint was change in the Unified MSA Rating Scale (UMSARS) total score from baseline to 48 weeks. (ClinicalTrials.gov NCT03589976).

RESULTS

The trial was stopped after a pre-planned interim analysis met futility criteria. Between August 15, 2018 and November 15, 2020, 54 participants were screened, and 47 enrolled and randomly assigned (35 sirolimus, 12 placebo). Of those randomized, 34 were included in the intention-to-treat analysis. There was no difference in change from baseline to week 48 between the sirolimus and placebo in UMSARS total score (mean difference, 2.66; 95% CI, -7.35-6.91; P = 0.648). There was no difference in UMSARS-1 and UMSARS-2 scores either. UMSARS scores changes were similar to those reported in natural history studies. Neuroimaging and blood biomarker results were similar in the sirolimus and placebo groups. Adverse events were more frequent with sirolimus. Analysis of 1-year biomarker trajectories in all participants showed that increases in blood neurofilament light chain (NfL) and reductions in whole brain volume correlated best with UMSARS progression.

CONCLUSIONS

Sirolimus for 48 weeks was futile to slow the progression of MSA and had no effect on biomarkers compared to placebo. One-year change in blood NfL and whole brain atrophy are promising biomarkers of disease progression for future clinical trials. © 2022 International Parkinson and Movement Disorder Society.

Factors modifying the likelihood of speeding behaviors based on naturalistic driving data

Speeding behaviors are quite common and are known to affect the risk and severity outcomes of vehicular crashes. Naturalistic driving data allows for the direct observation of speeding and the development of evidence-based causal structures for this behavior. This limits biases associated with self-reported speeding prevalence, allowing for more precise speeding measures than post-crash investigations and for the evaluation of driver attributes associated with speeding across a wide variety of locations and road types. Data from the Second Strategic Highway Research Program Naturalistic Driving Study were used to identify speeding events that were aggregated based on their duration and degree of speeding above the posted speed limit. The events were summarized as a likelihood of speeding metric for each trip in the dataset. These likelihood of speeding measurements were also aggregated across drivers and compared, using a beta binomial regression model, to driver questionnaire answers that addressed drivers' perception of their speeding as well as different driver-specific factors that are suspected of having an influence on speeding behaviors. Results showed that, consistent with past studies, age and gender significantly influenced the likelihood of speeding. For age, the odds of speeding exhibited a significant downward trend across increasing age groups; 16-24 year olds exhibited odds of speeding that were 1.5 times the odds of drivers that were 80 or more years old. For gender, males exhibited larger odds of speeding than females (1.1 times larger). In addition, the odds of speeding were larger at lower posted speed limits. The odds of speeding in 10-20 mph zones were 9.5 times the odds of zones with speed limits greater than 60 mph, implying that drivers may be unaware of the risks associated with speeding in low speed limit areas. Several questionnaire answers related to drivers' perception of speeding were also predictive of the likelihood of speeding.

Evaluating driver eye glance behavior and secondary task engagement while using driving automation systems

Partial driving automation systems are designed to assist drivers in some vehicle operation demands. However, modifications to the driving task that change the driver's role from that of an active participant to a passive supervisor could result in insufficient monitoring of the driving automation system and the surrounding environment. A reduced subset of driving data for 19 drivers from the Virginia Connected Corridors 50 Elite Naturalistic Driving Study was used to assess whether driver eye glance behavior and secondary task engagement were different when driver assistance systems were active compared to when they were available but inactive (n = 148). The results of this study demonstrate that drivers spent more time looking away from the road while driving automation systems were active and that drivers were more likely to be observed browsing on their cell phones while using driving automation systems. Current driving automation features require human monitoring of automation, yet the drivers of these automation-equipped vehicles are inclined to engage in secondary tasks and take longer and more frequent glances away from the roadway. It is possible that performance effects, such as omission errors or delayed reactions, may occur as a result of drivers' substandard monitoring of the driving scene.

Limitations of the Unified Multiple System Atrophy Rating Scale as outcome measure for clinical trials and a roadmap for improvement

PURPOSE

The unified multiple system atrophy (MSA) rating scale (UMSARS) was developed almost 20 years ago as a clinical rating scale to capture multiple aspects of the disease. With its widespread use, the shortcomings of the UMSARS as a clinical outcome assessment (COA) have become increasingly apparent. We here summarize the shortcomings of the scale, confirm some of its limitations with data from the Natural History Study of the Synucleinopathies (NHSS), and suggest a framework to develop and validate an improved COA to be used in future clinical trials of disease-modifying drugs in patients with MSA.

METHODS

Expert consensus assessment of the limitations of the UMSARS and recommendations for the development and validation of a novel COA for MSA. We used UMSARS data from the ongoing NHSS (ClinicalTrials.gov: NCT01799915) to showcase some of these limitations.

RESULTS

The UMSARS in general, and specific items in particular, have limitations to detect change resulting in a ceiling effect. Some items have specific limitations including unclear anchoring descriptions, lack of correlation with disease severity, susceptibility to improve with symptomatic therapies (e.g., orthostatic hypotension, constipation, and bladder dysfunction), and redundancy, among others.

CONCLUSIONS

Because of the limitations of the UMSARS, developing and validating an improved COA is a priority. The time is right for academic MSA clinicians together with industry, professional societies, and patient advocacy groups to develop and validate a new COA.

Modeled Wide-Awake, Local-Anesthetic, No-Tourniquet Surgical Procedures Do Not Impair Driving Fitness: An Experimental On-Road Noninferiority Study

BACKGROUND

The use of wide-awake, local-anesthetic, no-tourniquet (WALANT) surgical techniques is increasingly common, and patients commonly ask whether they may drive home following these procedures. The impact of a numb hand and bulky dressing on driving fitness is unknown, and there is no literature to guide surgeons when counseling these patients. Thus, the primary objective of the present study was to determine driving fitness following a modeled-WALANT procedure.

METHODS

Twelve right-handed individuals (6 male and 6 female) with an average age of 50 years (range, 38 to 64 years) were enrolled. An instrumented vehicle was used to obtain driving kinematic and behavioral data, thus allowing for a multidimensional assessment of driving fitness. Participants first performed a drive to establish baseline kinematic metrics. The route included both public streets and a closed course. Several driving tasks were assessed, including reverse parking, parallel parking, and perpendicular parking. The total course length was 18 miles (29 kilometers) and took 45 to 55 minutes to complete. After the first drive, 10 mL of 1% lidocaine was injected in the volar aspect of the right wrist and another 10 mL was injected into the right carpal tunnel to model the anesthetic used for a WALANT carpal tunnel release, and a bulky soft dressing was applied. The modeled-WALANT drive included an identical route and tasks, in addition to a surprise event to evaluate emergency responsiveness. Driving metrics were analyzed for noninferiority of the modeled-WALANT state to baseline driving.

RESULTS

The modeled-WALANT state showed noninferiority to baseline driving on all 11 analyzed dimensions of driving behavior compared with the control drives. In the modeled-WALANT state, participants drove more conservatively, braked harder, and steered more smoothly. All participants safely performed the 3 parking tasks and emergency response maneuver. Driving fitness in the modeled-WALANT state was noninferior to driving fitness in the preoperative drive.

CONCLUSIONS

A modeled-WALANT state has no clinically relevant negative impact on driving fitness, and thus surgeons should not discourage patients from driving home after unilateral WALANT surgical hand procedures.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Investigating lane change behaviors and difficulties for senior drivers using naturalistic driving data

INTRODUCTION

Lane changes can be a complicated maneuver occurring a dynamic environment requiring the integration of many streams of information. Older drivers may struggle with lane changes which may elevate crash risk.

METHODS

Real-world lane change behaviors were examined using the Second Strategic Highway Research Program Naturalistic Driving Study database. A total of 393 lane changes were observed for two age groups: middle-aged (30-49), and older (70+) drivers.

RESULTS

Older drivers were highly likely to fail to execute an over-the-shoulder glance prior to initiation of a lane change (in 98% of left lane changes and 92% for right lane changes). Older drivers also showed higher rates of OTS glance errors at any point during the lane change in 95% of left lane changes and 86% of right-lane changes. Additionally, older drivers frequently failed to activate the turn signal prior to lane change initiation (60% of lane changes for right changes and 59% for left lane changes). Of the older drivers that made side mirror glances, many occurred after the initiation of the maneuver (46% of left lane changes and 58% of right lane changes) suggesting glances were occurring while changing lanes.

CONCLUSIONS

Results for older drivers showed that many key glances (particularly side mirror checks) and turn signal actuations observed in the current study occurred after the initiation of the lane change, ostensibly when this action may be too late to gather relevant information and avoid a conflict. Practical Applications: Knowledge of glance patterns during lane changes for older drivers can help older drivers maintain travel mobility as they age. Either through training to reinforce OTS and side mirror glances, or supplemental devices like convex mirrors or oversized rearview mirrors, older drivers can reduce high-risk lane change maneuvers and help older drivers to maintain their mobility and independence longer.

The effects of age on crash risk associated with driver distraction

Background

Driver distraction is a major contributing factor to crashes, which are the leading cause of death for the US population under 35 years of age. The prevalence of secondary-task engagement and its impacts on distraction and crashes may vary substantially by driver age.

Methods

Driving performance and behaviour data were collected continuously using multiple cameras and sensors in situ for 3542 participant drivers recruited for up to 3 years for the Second Strategic Highway Research Program Naturalistic Driving Study. Secondary-task engagement at the onset of crashes and during normal driving segments was identified from videos. A case-cohort approach was used to estimate the crash odds ratios associated with, and the prevalence of, secondary tasks for four age groups: 16-20, 21-29, 30-64 and 65-98 years of age. Only severe crashes (property damage and higher severity) were included in the analysis.

Results

Secondary-task-induced distraction posed a consistently higher threat for drivers younger than 30 and above 65 when compared with middle-aged drivers, although senior drivers engaged in secondary tasks much less frequently than their younger counterparts. Secondary tasks with high visual-manual demand (e.g. visual-manual tasks performed on cell phones) affected drivers of all ages. Certain secondary tasks, such as operation of in-vehicle devices and talking/singing, increased the risk for only certain age groups.

Conclusions

Teenaged, young adult drivers and senior drivers are more adversely impacted by secondary-task engagement than middle-aged drivers. Visual-manual distractions impact drivers of all ages, whereas cognitive distraction may have a larger impact on young drivers.

A validation of the low mileage bias using naturalistic driving study data

INTRODUCTION

This paper evaluated the low mileage bias (LMB) phenomenon for senior drivers using data mined from the Second Strategic Highway Research Program (SHRP 2) Naturalistic Driving Study. Supporters of the LMB construct postulate that it is only those seniors who drive the lowest annual mileage who are primarily responsible for the increased crash rates traditionally attributed to this population in general.

METHOD

The current analysis included 802 participants, all aged 65 or older who were involved in 163 property damage and injury crashes, and deemed to be at-fault in 123 (75%) of those instances. Poisson regression models were used to evaluate the association between annualized mileage driven and crash risk.

RESULTS

Results show that the crash rate for drivers with lower annualized mileage (i.e., especially for those driving fewer than approximately 3000miles per year) was significantly higher than that of drivers with higher annualized mileage, and that 25% of the overall sample were low- mileage drivers according to this criterion. Data were also evaluated by gender and meta-age group (i.e., younger-old: 65-74 and older-old: 75-99), and the results were consistent across these sub-groups.

CONCLUSIONS

This study provides strong support for the existence of the LMB.

PRACTICAL APPLICATIONS

These results can help to reshape how transportation safety stakeholders view senior drivers in general and help them to focus their efforts on those seniors most in need of either risk-reducing countermeasures or alternative means of transportation.

Sudden Unexpected Death During Sleep in Familial Dysautonomia: A Case-Control Study

Study Objectives

Sudden unexpected death during sleep (SUDS) is the most common cause of death in patients with familial dysautonomia (FD), an autosomal recessive disease characterized by sensory and autonomic dysfunction. It remains unknown what causes SUDS in these patients and who is at highest risk. We tested the hypothesis that SUDS in FD is linked to sleep-disordered breathing.

Methods

We retrospectively identified patients with FD who died suddenly and unexpectedly during sleep and had undergone polysomnography within the 18-month period before death. For each case, we sampled one age-matched surviving subject with FD that had also undergone polysomnography within the 18-month period before study. Data on polysomnography, EKG, ambulatory blood pressure monitoring, arterial blood gases, blood count, and metabolic panel were analyzed.

Results

Thirty-two deceased cases and 31 surviving controls were included. Autopsy was available in six cases. Compared with controls, participants with SUDS were more likely to be receiving treatment with fludrocortisone (odds ratio [OR]; 95% confidence interval) (OR 29.7; 4.1-213.4), have untreated obstructive sleep apnea (OR 17.4; 1.5-193), and plasma potassium levels <4 mEq/L (OR 19.5; 2.36-161) but less likely to use noninvasive ventilation at night (OR 0.19; 0.06-0.61).

Conclusions

Initiation of noninvasive ventilation when required and discontinuation of fludrocortisone treatment may reduce the high incidence rate of SUDS in patients with FD. Our findings contribute to the understanding of the link between autonomic, cardiovascular, and respiratory risk factors in SUDS.

Performance of basic kinematic thresholds in the identification of crash and near-crash events within naturalistic driving data

Understanding causal factors for traffic safety-critical events (e.g., crashes and near-crashes) is an important step in reducing their frequency and severity. Naturalistic driving data offers unparalleled insight into these factors, but requires identification of situations where crashes are present within large volumes of data. Sensitivity and specificity of these identification approaches are key to minimizing the resources required to validate candidate crash events. This investigation used data from the Second Strategic Highway Research Program Naturalistic Driving Study (SHRP 2 NDS) and the Canada Naturalistic Driving Study (CNDS) to develop and validate different kinematic thresholds that can be used to detect crash events. Results indicate that the sensitivity of many of these approaches can be quite low, but can be improved by selecting particular threshold levels based on detection performance. Additional improvements in these approaches are possible, and may involve leveraging combinations of different detection approaches, including advanced statistical techniques and artificial intelligence approaches, additional parameter modifications, and automation of validation processes.

[The neural networks of facial expression]

INTRODUCTION

Face perception involves a broad network of connections between cortical and subcortical regions for the exchange and synchronization of information using white matter fibers. This precise communication system can be affected by the structures and the pathways that connect them.

AIMS

To establish the neural substrate underlying the perception of facial expression and to analyze the different factors involved in modulating the integrity of this neural network, with the aim being to introduce improvements into rehabilitation programs.

DEVELOPMENT

When the complex neural network involved in the perception of facial expression is altered by trauma, neurodegenerative disorders, developmental disorders, social isolation or negative contexts, the adaptive capacity to interact with the environment also deteriorates.

CONCLUSIONS

Maintaining the neural network integrity responsible for processing facial expression requires considering different variables. To a greater or lesser extent, these variables modify the structure or function of neural networks, such as aerobic training, transcranial magnetic stimulation, transcranial electrical stimulation, and learning. These variables are affected by age, and the type and course of the condition or generator context, and raise the need for rehabilitation protocols that are adapted and designed to delimit the deficient neuronal substrate.

Effects of Haptic Brake Pulse Warnings on Driver Behavior during an Intersection Approach

Intersection crashes account for nearly a quarter of all police reported crashes, and 39% of these result in injury or death. In this experiment, haptic warnings were explored as an alternative to auditory and visual warnings as part of an overall effort to reduce the number of intersection related crashes. The study objective was to determine the haptic brake pulse warning candidate that most often results in the driver successfully stopping for an intersection. Five candidate brake pulse warnings were tested; these varied with respect to length and number of pulses. Significant differences were found between haptic conditions for peak and constant deceleration. Participants receiving the haptic warning were 38 times more likely to stop than those receiving no warning.

Gold-palladium core@shell nanoalloys: experiments and simulations

In this work, we report a facile synthesis route, structural characterization, and full atomistic simulations of gold-palladium nanoalloys. Through aberration corrected-STEM, UV-vis spectroscopy and EDS chemical analysis, we were able to determine that Au(core)-Pd(shell) bimetallic nanoparticles were formed. Using different computational approaches, we were capable of establishing how the size of the core and the thickness of the shell will affect the thermodynamic stability of several core-shell nanoalloys. Finally, grand canonical simulations using different sampling procedures were used to study the growth mechanism of Pd atoms on Au seeds of different shapes.

Drivers' visual behavior when using handheld and hands-free cell phones

OBJECTIVE

This study investigated driver distraction and how the use of handheld (HH), portable hands-free (PHF), and integrated hands-free (IHF) cell phones affected the visual behavior of motor vehicle drivers.

METHOD

A naturalistic driving study recorded 204 participating drivers using video cameras and vehicle sensors for an average of 31 days. A total of 1564 cell phone calls made and 844 text messages sent while driving were sampled and underwent a video review. Baselines were established by recording epochs prior to the cell phone interactions. Total eyes-off-road time (TEORT) was examined to assess the visual demands of cell phone subtasks while driving. Percent TEORT was reported and compared against the baseline.

RESULTS

Visual-manual subtasks performed on HH, PHF, and IHF cell phones were found to significantly increase drivers' mean percent TEORT. In contrast, conversing on an HH cell phone was found to significantly decrease drivers' mean percent TEORT, indicating that drivers looked at the forward roadway more often. No significant differences in percent TEORT were found for drivers conversing using PHF or IHF cell phones. The mean TEORT durations for visual-manual subtasks performed on an HH cell phone were significantly longer than the mean TEORT durations on either IHF or PHF cell phones.

PRACTICAL APPLICATIONS

This research helps to further reinforce the distinction made between handheld and hands-free cell phone use in transportation distraction policy.

Assessment of naturalistic use patterns of advanced infotainment systems

OBJECTIVE

The objective was to examine naturalistic usage of infotainment systems to assess use characteristics and patterns.

BACKGROUND

Infotainment systems continue to evolve in terms of their capabilities and information availability, raising concerns about their distraction potential. Assessing potential distraction requires understanding how challenging different tasks are and how frequently they occur during driving.

METHOD

High-end infotainment system use was observed across 17 participants over a period of approximately 4 weeks each. One of two different infotainment systems was provided to participants. Audio, video, and driving performance data were collected and observed by trained reductionists. The two infotainment systems integrated iPod™, satellite radio, CD/DVD/MP3 playback, AM/FM, and, in one case, navigation functionalities. Systems differed in their vehicle integration and advanced infotainment features offered.

RESULTS

The median participant interacted with the infotainment systems once every 4 hr (90th percentile: 6.1 interactions/hr). More than 50% of these interactions involved adjusting the volume. Although there were a few lengthy interactions, the median duration was 2.2 s (90th percentile: 24.6 s), which required measurable visual involvement when compared to a matched baseline. The median total eyes-off-road time across interactions was 1 s (90th percentile: 11.4 s) and differed significantly across type of system interaction. Longer interactions tended to occur when the vehicle was stationary.

CONCLUSION

Drivers habitually interact with infotainment systems while driving; this includes advanced functions. Some self-regulation was observed.

APPLICATION

These data provide a comparison basis for use in examining driver interactions with future infotainment systems.

Safety implications of infotainment system use in naturalistic driving

The use of a radio while driving has long been considered a "threshold" of distraction that is socially acceptable although it may be a factor in some crashes and near crashes. This "social acceptance" has prompted the use of radio tasks, specifically radio tuning, as "references" that should not be exceeded by other secondary and tertiary tasks that make their way into the vehicle. As new functions make their way into vehicle radios (or more advanced infotainment systems), however, it is possible that radio tasks may become distracting to a level that surpasses current driver expectations. This investigation examines the naturalistic usage of several advanced infotainment systems and examines whether usage is associated first with changes in near crash occurrence and second with changes in driving behavior. Little association was found with near crashes: 5 of 46 near crash events observed in the dataset exhibited infotainment system use. Drivers involved in infotainment system use during near crashes, however, did exhibit distinct glance behaviors, generally suggesting lower levels of awareness about their driving environment. Initial analyses of a larger dataset appear to confirm these findings.

Comparing handheld and hands-free cell phone usage behaviors while driving

OBJECTIVE

The goal of this study was to compare cell phone usage behaviors while driving across 3 types of cell phones: handheld (HH) cell phones, portable hands-free (PHF) cell phones, and integrated hands-free (IHF) cell phones. Naturalistic driving data were used to observe HH, PHF, and IHF usage behaviors in participants' own vehicles without any instructions or manipulations by researchers.

METHODS

In addition to naturalistic driving data, drivers provided their personal cell phone call records. Calls during driving were sampled and observed in naturalistically collected video. Calls were reviewed to identify cell phone type used for, and duration of, cell phone subtasks, non-cell phone secondary tasks, and other use behaviors. Drivers in the study self-identified as HH, PHF, or IHF users if they reported using that cell phone type at least 50% of the time. However, each sampled call was classified as HH, PHF, or IHF if the talking/listening subtask was conducted using that cell phone type, without considering the driver's self-reported group.

RESULTS

Drivers with PHF or IHF systems also used HH cell phones (IHF group used HH cell phone in 53.2% of the interactions, PHF group used HH cell phone for 55.5% of interactions). Talking/listening on a PHF phone or an IHF phone was significantly longer than talking/listening on an HH phone (P <.05). HH dialing was significantly longer in duration than PHF or IHF begin/answer tasks. End phone call task for HH phones was significantly longer in duration than the end phone call task for PHF and IHF phones. Of all the non-cell phone-related secondary tasks, eating or drinking was found to occur significantly more often during IHF subtasks (0.58%) than in HH subtasks (0.15%). Drivers observed to reach for their cell phone mostly kept their cell phone in the cup holder (36.3%) or in their seat or lap (29.0% of interactions); however, some observed locations may have required drivers to move out of position.

CONCLUSIONS

Hands-free cell phone technologies reduce the duration of cell phone visual-manual tasks compared to handheld cell phones. However, drivers with hands-free cell phone technologies available to them still choose to use handheld cell phones to converse or complete cell phone visual-manual tasks for a noteworthy portion of interactions.

Central common drive to antagonistic ankle muscles in relation to short-term cocontraction training in nondancers and professional ballet dancers

Optimization of cocontraction of antagonistic muscles around the ankle joint has been shown to involve plastic changes in spinal and cortical neural circuitries. Such changes may explain the ability of elite ballet dancers to maintain a steady balance during various ballet postures. Here we investigated whether short-term cocontraction training in ballet dancers and nondancers leads to changes in the coupling between antagonistic ankle motor units. Eleven ballet dancers and 10 nondancers were recruited for the study. Prior to training, ballet dancers and nondancers showed an equal amount of coherence in the 15- to 35-Hz frequency band and short-term synchronization between antagonistic tibialis anterior and soleus motor units. The ballet dancers tended to be better at maintaining a stable cocontraction of the antagonistic muscles, but this difference was not significant (P = 0.09). Following 27 min of cocontraction training, the nondancers improved their performance significantly, whereas no significant improvement was observed for the ballet dancers. The nondancers showed a significant increase in 15- to 35-Hz coherence following the training, whereas the ballet dancers did not show a significant change. A group of control subjects (n = 4), who performed cocontraction of the antagonistic muscles for an equal amount of time, but without any requirement to improve their performance, showed no change in coherence. We suggest that improved ability to maintain a stable cocontraction around the ankle joint is accompanied by short-term plastic changes in the neural drive to the involved muscles, but that such changes are not necessary for maintained high-level performance.

Effect of CYP3A51/3 polymorphism on blood pressure in renal transplant recipients

BACKGROUND

The cytochrome P450 3A5 (CYP3A5) enzyme has been implicated to determine blood pressure (BP) in humans. Different results have been reported concerning CYP3A5 gene polymorphisms and posttransplantation hypertension in kidney recipients. Our objective was to investigate whether CYP3A5 1/3 polymorphism was associated with ambulatory BP among a population of renal transplant recipients receiving the calcineurin inhibitor tacrolimus for immunosuppression.

METHODS

Sixty primary kidney transplant recipients undergoing treatment with tacrolimus were genotyped for the CYP3A5 1/3 polymorphism. We analysed the association of the CYP3A5 alleles with ambulatory systolic and diastolic BP measured at 6 and 24 months posttransplantation.

RESULTS

We observed that 23.3% of the patients were CYP3A5 1 carriers and 76.7% were homozygous for CYP3A5 3. CYP3A5 1 carriers showed higher adjusted systolic BP and diastolic BP at 6 and 24 months posttransplantation, and they were prescribed more antihypertensive drugs compared with non CYP3A5 1 carrier patients, albeit not significant. No significant differences were found comparing the distribution of the hypertension classes.

CONCLUSION

We did not observe a significant association of CYP3A5 1/3 polymorphism with posttransplantation hypertension, although there were some differences in BP associated with the presence of the CYP3A5 1 allele.

Getting to Know US Latinos

Data from the 2010 US Census Bureau, Latinos are one of the largest non-White groups in the United States, a trend expected to continue during the next two decades. Despite their status as the largest nonWhite populations in the US, Latinos continue to be poorly understood and their heterogeneous backgrounds are often ignored. The purpose of this paper is to describe an interactive learning activity designed to explore Latino demographics, food preferences, and culturally-specific health practices and beliefs among this population that traces its roots to many Latin American countries extending from Mexico to Tierra del Fuego and some Caribbean islands. The activity described in this paper is designed for English speaking audiences and may be used with junior or senior high school or college students

Preparing for an influenza pandemic: policy implications for rural Latino populations

Abstract:The purpose of this study was to assess influenza preparedness levels among Spanish-speaking adults ages 18 and older in two rural communities in Central California. Data were collected from 209 participants using the 21-item Emergency Preparedness Measurement Scale, an instrument designed and validated for this study. Results suggest that adult Spanish-speaking Latinos are not prepared for a pandemic influenza regardless of their gender, age, number of years living in the United States, education, or income level. Furthermore, study participants cited lack of insurance, limited knowledge about needed emergency supplies, and preference for fresh foods as reasons for lacking emergency supplies at home.

The Distracted Driver

This chapter investigates driver distraction, a pressing road safety issue. First, research findings regarding the demands placed on drivers by the primary driving tasks and various non-driving-related secondary tasks are reviewed. Second, promising theories and models are reviewed for characterizing how driver distraction is caused and how it affects the driving task. Third, a review is provided of current investigation and measurement methods used in distraction research, guidelines, standards, antidistraction devices, and antidistraction legislation. Fourth, the most important implications from this review are summarized for the various stakeholders in the driver distraction debate. And finally, some important issues for future research into driver distraction are discussed, as is the importance of considering driver distraction in the context of an integrated safety vision.

Vascular calcification and 25-hydroxyvitamin D levels in non-dialysis patients with chronic kidney disease stages 4 and 5

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of death among chronic kidney disease (CKD) patients. Vascular calcification is highly prevalent in this population and is an independent predictor of cardiovascular mortality. Vascular calcification in uraemic patients is known to be an active and regulated process subject to the action of many promoting and inhibitory factors. The role of vitamin D in this process remains controversial. We evaluated the relationship between serum levels of 25-hydroxyvitamin D (25(OH)D) and vascular calcification evaluated by plain X-ray images, in predialysis patients with CKD stages 4 and 5.

METHODS

We performed a cross-sectional study with 210 CKD patients stages 4 and 5 managed at our predialysis unit. Patients were 63.5 ± 13 years of age, 60.5% males, 64.8% diabetics and 47.1% with a history of CVD. Plain X-ray images of pelvis, hands and lateral lumbar spine from all subjects were studied for calculation of semiquantitative vascular calcification scores as described by Adragao and Kauppila.

RESULTS

We found a high prevalence of vascular calcification in our population. Adragao scores revealed only 47 patients (22.4%) without vascular calcification and 120 (57.1%) with scores higher than 3. Kauppila scores revealed only 29 patients (13.8%) without aortic calcifications and 114 patients (54.3%) with scores higher than 7. Higher vascular calcification scores were related to older age, diabetes, history of CVD and lower levels of 25(OH)D. Only 18.5% of patients had adequate levels of 25(OH)D (> 30 ng/mL), 53.7% of them had insufficient levels (15-30 ng/mL) and 27.8% had deficient levels (< 15 ng/mL). Multivariate analysis showed that age, diabetes and CVD were directly associated and 25(OH)D levels were inversely associated with vascular calcifications.

CONCLUSIONS

Our results show an independent and negative association between serum levels of 25(OH)D and vascular calcification. Further and larger prospective studies are needed to clarify the possible role of vitamin D deficiency in the development of vascular calcification in CKD patients.

Functional neuroanatomy of mirroring during a unimanual force generation task

Performance of a unimanual motor task often induces involuntary mirror electromyographic (EMG) activity in the opposite, resting hand. In spite of the ubiquitous presence of mirroring, little is known regarding the underlying cortical contributions. Here, we used functional magnetic resonance imaging (fMRI) to study brain regions activated in association with parametric increases in right isometric wrist flexion force (10%, 20%, 30%, and 70%) in 12 healthy volunteers. During scanning, EMG activity was recorded bilaterally from flexor carpi radialis (FCR), extensor carpi radialis (ECR), biceps brachii (BB), and triceps brachii (TB). Mirror EMG was observed in left FCR during 20%, 30%, and 70% of force. Left ECR, BB, and TB showed mirror EMG only at 70% of force. Increasing force was associated with a linear increase of blood-oxygen-level-dependent (BOLD) signal in bilateral primary motor cortex (M1), supplementary motor area (SMA), caudal cingulate, and cerebellum. Mirroring in the left FCR correlated with activity in bilateral M1, SMA, and the cerebellum. Overall, our results suggest that activity in these regions might reflect sensorimotor processes operating in association with mirroring and suggest caution when interpreting fMRI activity in studies that involve unilateral force generation tasks in the absence of simultaneous bilateral EMG/kinematics measurements.

A neural network model for predicting postures during non-repetitive manual materials handling tasks

Posture prediction can be useful in facilitating the design and evaluation processes for manual materials handling tasks. This study evaluates the ability of artificial neural network models to predict initial and final lifting postures in 2-D and 3-D scenarios. Descriptors for the participant and condition of interest were input to the models; outputs consisted of posture-defining joint angles. Models were trained with subsets of an existing posture database before predictions were generated. Trained models predictions were then evaluated using the remaining data, which included conditions not presented during training. Prediction errors were consistent across these data subsets, suggesting the models generalised well to novel conditions. The models generally predicted whole-body postures with per-joint errors in the 5 degrees -20 degrees range, though some errors were larger, particularly for 3-D conditions. These models provided reasonably accurate predictions, even outperforming some computational approaches previously proposed for similar purposes. Suggestions for future refinement of such models are presented. The models in this investigation provide a means to predict initial and final postures in commonly occurring manual materials handling tasks. In addition, the model structures provide information about potential lifting strategies that may be used by individuals with particular anthropometry or strength characteristics.

Different roads, same destination: launching regional training centres

The four Regional Training Centres (RTCs) founded by the Canadian Health Services Research Foundation and the Canadian Institutes of Health Research have used their regional context and resources to develop an innovative approach to reach their common goal of increasing capacity in applied health and nursing services research in Canada. As this overview explains, experiential learning features prominently in all four RTCs with the involvement of healthcare decision-makers and organizations. An interdisciplinary conceptual and methodological approach has been emphasized, resulting in both a regional and a national network of faculty, researchers, healthcare decision-makers and graduate students who are committed to the field of applied health and nursing services research. Faculty, decision-makers and students have gained a deeper understanding of how to achieve knowledge translation and exchange within the context of applied health and nursing services research to promote evidence-informed decision-making.

Histomorphometric study of femoral heads in hip osteoarthritis and osteoporosis

During the period from 2000 to 2003, ninety eight samples of femoral heads were collected. In these pieces, two zones were analyzed: a high-load zone (the hard core of the head) and a low-load zone (the round ligamentum teres zone). As control group, 6 femoral heads (3 of women and 3 of men), proceeding from autopsy in peoples without pathological antecedents and youngs, were studied. After the samples had been embedded in methylmethacrylate and stained, they were subjected to an histomorphometric study. By means of histomorphometry, trabecular bone volume (TBV) and osteoid substance (OSV) was determined. Statistically significant differences were found as for peripheral osteoid volume (low-load zone) (p=0.036) and trabecular bone volume, both peripheral and central. Both volumes decreased in osteoporotic samples and in those from women (p=0.000), in comparison with control group. Regarding the relationship between the high-load and low-load zone, significant data were obtained. The high-load zone had a greater trabecular bone volume than the low-load zone, regardless of the pathology and sex, but this increase was more pronounced in the arthrosic samples and in those from men. Additionally, this trabecular bone volume in the high-load zone decreased with increasing age of the donor (p=0.037), when the control group is compared. In sum, we observed a reduction in the formation of TBV and OSV in osteoporosis but also a decrease in the arthrosic, in samples from older subjects, in women, and in the low-load zone of the samples, when the control group is compared. These data suggest the coexistence of both pathologies, which is more pronounced in older subjects and women.

Evaluation of transcranial magnetic stimulation for investigating transmission in descending motor tracts in the rat

In the rat, non-invasive transcranial magnetic stimulation (TMS) has shown promise for evaluation of transmission through the spinal cord before and after repair strategies, but it is still unclear which pathways are activated by TMS. The aim of the present study was therefore to identify these pathways and to analyse the effect of TMS on spinal neurons. In 19 rats, TMS evoked responses bilaterally in forelimb (biceps brachii; BB) and hindlimb muscles (tibialis anterior). The latency and amplitude of these motor-evoked responses (MEPs) were highly variable and depended strongly on the coil position and the stimulation intensity. The most frequently observed latencies for the BB MEPs could be divided into three groups: 3-6 ms, 8-12 ms and 14-18 ms. Lesions in the dorsal columns, which destroyed the corticospinal tract at C2 and C5, significantly depressed MEPs in the mid- and high-latency ranges, but not those in the low-latency range. Lesions in the dorsolateral funiculus, which interrupted the rubrospinal tract, had no effect on MEPs in any of the latency ranges. By contrast, bilateral lesion of the reticulospinal tract and other ventro-laterally located descending pathways abolished all responses. Intracellular recordings from 54 cervical motoneurons in five rats revealed that TMS evoked excitatory postsynaptic potentials (EPSPs) at latencies that corresponded well with those of the BB MEPs. The short-latency EPSPs had rise times of around 1 ms, suggesting that they were mediated by a monosynaptic pathway. EPSPs with longer latencies had considerably longer rise times, which indicated conduction through polysynaptic pathways. Selective electrical stimulation of the pyramidal tract in the brainstem was performed in seven rats, where intracellular recordings from 70 motoneurons revealed that the earliest EPSPs and MEPs evoked by TMS were not mediated by the corticospinal tract, but by other descending motor pathways. Together, these results showed that in the rat TMS activates several descending pathways that converge on common spinal interneurons and motoneurons. Our observations confirm that the corticospinal tract has weak (and indirect) projections to cervical spinal motoneurons.

A comparison of ozone exposure in Fresno and Shaver Lake, California

Ground-level ozone is a pollutant that has been found to have detrimental effects on plants as well as in humans. Few studies, however, have measured ozone exposure in mountainous regions downwind from highly polluted urban centers, despite the popularity of these regions as summer destinations. The study reported here evaluated ozone levels in Fresno, California, and the downwind community of Shaver Lake, California, during the summer months of June, July, and August from 1997 to 2001. Findings from the study suggest that if Fresno is considered one of the most polluted cities in the nation, then Shaver Lake should be considered one of the most polluted rural sites. Continuing and expanded monitoring of surface ozone concentrations at remote and rural locations is needed, because it is important to assess the risk for humans, animals, and plants.

In situ detection of SOCS and cytokine expression in the uterine cervix from HIV/HPV coinfected women

The purpose of this study was to look for associations between a newly described class of suppressors of cytokine signaling (SSI/SOCS) and cytokine expression in the uterine cervix from HIV/HPV coinfected women. We examined the pro-inflammatory cytokines TNF-alpha and IL-6 since their expressions are linked and responsible for many aspects of both localized and systemic inflammatory responses. Further, expression of SSI/SOCS has been implicated in the negative feedback regulation of cytokine receptor signaling. PCR-amplified HIV-1 cDNA was noted mainly in the stroma, showing a perivascular distribution, and most of the infected cells colabeled with the macrophage marker CD68. The distribution of IL-6 and TNF-alpha was in the same area to HIV-1 and much greater than normal cervices from women with no evidence of viral infection. SOCS/SSI-1 and -3 mRNA positive cells in the uterine cervix were commonly detected in these noninfected cervical tissues; however, very few cells that contained SOCS were evident in areas where HIV-1, TNF-alpha, and IL-6 expressing cells were found. This suggests that viral-related suppression of SOCS/SSI-1-3 expression may be a factor in the marked local enhancement of TNF-alpha and IL-6 production which, in turn, may help facilitate viral spread; however, further studies should be done in order to elucidate the exact mechanisms of SOCS in the cervix.

Posture and motion variability in non-repetitive manual materials handling tasks

In developing a motion prediction model it is important to initially consider the sources of variability that a model should reproduce. This initial step is followed by model evaluation, where the variability predicted by the model can be a useful test parameter. An existing lifting-motion dataset collected under controlled laboratory conditions was employed here to evaluate quantitatively some important sources of variability for lift motion modeling. The main source of variability was the segment being analyzed, which accounted for more than 20% of the overall variability. There was substantial left-right symmetry in individual segment variability estimates, which were largest for the upper arm segment and tended to be larger for the upper limbs than the lower limbs. Task-related factors accounted for variability mainly as a function of the segment being considered. Within-participant variability contributions to the dataset were relatively small, whereas the contribution of between-participants variability was dependent on the segment (as large as 50%) and could indicate different lifting strategies across participants. Variability was found to remain relatively constant across the different stages of the lifting movements. Implications of these results for the development and evaluation of motion prediction models are presented. Specifically, while task characteristics may be important modifiers of the mean segment trajectory during a lifting movement, their influence on variability differs based on the segment that is being considered. The relevance of the findings is discussed in terms of their utility in the ergonomic design of tasks and work spaces.

Cultural Competence in Health Care Systems

This study studied cultural competence training needs in a health services system in California. Results indicated that the major training needs were related to (1) cultural factors that affect consumers’ access to services, (2) ethnic and cultural beliefs, traditions, and customs, (3) training for interpreters, and (4) crosscultural communication. Significant differences were found in regard to administrator and staff participation in cultural awareness activities, perception of the work environment as culturally competent, perception of culturally-related barriers, and perceived training needs. The findings support the importance of a continuous assessment of the educational needs of employees regarding cultural competence.

Periprosthetic bone remodeling. A finite elementstudy of the influence of the implant design

Remodeling periprosthetic femoral bone after total hip arthroplasty has been studied extensively. Finite element (FE) analysis, together with mathematical remodeling theories, has predicted that femoral bone-mineral density decreases proximally after total hip arthroplasty. There is significant controversy concerning the clinical consequences of bone remodeling such as the reduction in bone strength, the possibility of a cement mantle fracture, the aseptic loosening of the implant, or the appearance of a periprosthetic fracture, which could threaten the survival of the hip prosthesis. The status of periprosthetic bone stock is an important concern when total hip arthroplasty revision is undertaken. This study was conducted to evaluate the periprosthetic bone-mineral density evolution following primary total hip arthroplasty by FE analysis. We compared two cemented stems with different designs: the Exeter and the SHP to study the phenomenon of femoral stress shielding and bone cement deterioration. We found that with the best mechanical conditions and with the same materials, the prosthesis design determines a different periprosthetic bone remodeling.

Principal components analysis as an evaluation and classification tool for lower torso sEMG data

The use of univariate statistical techniques on multivariate electromyography data can fail to uncover important relationships between variables. Principal components analysis (PCA) is a multivariate statistical technique that can be used as a data exploration tool, both by classifying participants and simplifying data structures. Past research using this technique has focused on discriminating between "patients" and "normals". This investigation explored the use of PCA on electromyography data from healthy participants, with the objective of elucidating any between-participant differences in the multivariate patterns of muscle coactivation. Results indicated that, even between healthy participants, quantitative and qualitative differences in muscle coactivation patterns exist and that, in the context of the lower torso, a large portion (>70%) of the empirically determined muscle activation could be synthesized in a theoretical three-parameter control model.

Identification of the vectors of lymphatic filariasis in the Lower Shire Valley, southern Malawi

An investigation of lymphatic filariasis vectors in Malawi is reported. Anopheles funestus, A. arabiensis, and A. gambiae sensu stricto had high rates of filarial infection (2.2-3.1%) and carried infective larvae. Anopheles funestus was the predominant species collected (77.6%) and was the primary vector during the study period of April to May 2002.

Lower torso muscle activation patterns for high-magnitude static exertions: gender differences and the effects of twisting

STUDY DESIGN

Surface electromyographic signals were collected from 14 lower torso muscles while participants resisted high-magnitude static trunk moments applied in a variety of directions.

OBJECTIVES

To obtain a description of muscle activations in response to large moment magnitudes and axial twisting, including levels of agonistic and antagonistic muscle cocontraction. To assess differences in lower torso muscle activation patterns associated with gender and trial repetition.

SUMMARY OF BACKGROUND DATA

Back pain is associated with mechanical loads in the back. Biomechanical modeling of these loads is facilitated by knowledge of typical muscle activation patterns. Previous efforts in obtaining such data have often limited their scope to low-magnitude exertions or relatively simple scenarios.

METHODS

Eight male and eight female participants, matched by height and mass, performed static exertions in an apparatus that immobilized their lower body while the activation levels of seven bilateral torso muscles were measured using surface electromyography. Activation patterns were analyzed to assess differences resulting from a variety of factors.

RESULTS

No significant differences in activation patterns were found between genders or repetitions, but moment magnitude and direction elicited substantial differential responses. Good repeatability was found between trial repetitions, as indicated by intraclass correlation coefficients (>0.65). Significant synergistic muscle coactivation, large intersubject variability (mean coefficient of variation 82.2%), and consistent levels of antagonism ranging from 10% to 30% maximum voluntary exertions were observed.

CONCLUSIONS

Individuals of different genders, but similar anthropometry, have comparable muscular reactions to complex torso loads, suggesting similar motor control strategies. Future spine models should consider that the variability in muscle recruitment patterns is larger between subjects than within subjects. High-magnitude exertions, especially those with moment loads in more than one plane, require most muscles to be active (>5%) and moderate levels of antagonism.