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Kumar S.,Safety Research Institute | Herbst B.,SAFE , LLC | Strickland D.,Safety Research Institute | Strickland D.,Gainesville State College
Biomedical Sciences Instrumentation | Year: 2012

Traumatic brain injuries (TBI) are common in sports accidents. Helmets are generally known to provide protection to the head. However, the effectiveness of helmets in mitigating a TBI may be compromised due to the impact location and impact speed. Although it is known that the helmet decreases the linear head accelerations and the resulting head injury potential, to the best of our knowledge, limited research effort has been devoted to the study of the biomechanics of TBI in side impact conditions. The present work is designed to delineate the biomechanics of TBI in a fall impacting the parietal/temporal regions. A standing Hybrid III male dummy with pedestrian pelvis was used. The dummy was placed on a swinging platform for the fall simulation. The drop was achieved by stopping the platform with a block. The platform was swung from a predetermined height and stopped to allow the free fall of the dummy. The test was conducted with and without a skate board helmet. The impact on the dummy's head was in the parietal and temporal regions. The head impact speed with the floor was approximately 24 kph (6.7 m/sec) The dummy was instrumented with tri-axial linear and tri-axial angular head accelerometers to measure the biomechanical injury responses. Results from three tests were compared. The linear head CG acceleration, Head Injury Criteria (HIC) and angular head accelerations were compared. Results suggest that the helmet reduced the linear head acceleration, HIC and angular head acceleration compared to the impact without a helmet. Although the linear head accelerations and HIC were reduced, the angular head accelerations even with the helmet were above nearly all proposed rotational head injury threshold in the literature. The higher angular head accelerations indicate a higher probability of concussion, acute subdural hematoma and diffuse axonal injuries. The present study is an additional step to better understand the biomechanics of TBI and the role of protective headgear systems in sports and recreational accidents. © 2012. All Rights Reserved. Source

Kumar S.,Safety Research Institute | Harcourt J.,Emtec | Herbst B.,SAFE , LLC | Strickland D.,Safety Research Institute | Strickland D.,Gainesville State College
Biomedical Sciences Instrumentation | Year: 2012

Airbag related injuries to infants in rear facing child seats are common in frontal crashes. Several vehicular modifications such as deactivated passenger airbags, manual cut-off switches, depowered airbags and smart airbags have been advanced to mitigate the effect of airbag deployment on child seats. However, there is limited research effort to address the biomechanics of airbag injuries due to modification in child restraint systems. The purpose of this research is to evaluate the biomechanical effects of a protective barrier between the rear facing child restraint and the frontal passenger airbag of the vehicle. An experimental study was conducted using an Anthropometric Test Dummy (ATD) in a vehicular partial structure (buck). The rear facing child seat was placed in the right front passenger seat of the vehicle. The child seat was restrained using the three-point restraint in the vehicle. The six-month-old instrumented ATD was restrained in the child seat. The ATD was instrumented with the head tri-axial and two uni-axial linear accelerometers. The uni-axial linear acceleration was used to calculate the angular acceleration. Two different rear facing child seats, the standard rear facing infant seat and the rear facing infant seat inside the protective barrier structure were tested. In each test, the Head Injury Criteria (HIC) and angular head acceleration were measured. Results show that the HIC was reduced by 95% and the angular head acceleration was reduced by 85% by the protective barrier. The head injury values were well below the tolerance limit for the child with the barrier. The protective barrier deflected the airbag away from the ATD's head and also acted as a shield to minimize airbag force on the child seat. In the typical infant seat, the airbag contacted the ATD's head and exerted significant force on the child seat which rotated the seat rearward. These kinematic responses may explain the clinical observation of severe head injuries by infants in rear facing seats due to forces transmitted through the child seat and downward force from the top of the head. The present study is a first step in better understanding the injury mitigating aspects of the safety protective structure in child restraints. © 2012. All Rights Reserved. Source

Breiding M.J.,Centers for Disease Control and Prevention | Ziembroski J.S.,Gainesville State College
Pediatric Allergy and Immunology | Year: 2011

Intimate partner violence (IPV) has been shown to negatively impact the health of both the adults who experience IPV and the children who are exposed to IPV. Although IPV experienced by women has been linked to children's asthma, this study is the first to examine this question among both women and men, and the first study in the United States to examine this question as part of a population-based data set. In 2005, ten US states/territories administered an IPV module and a children's asthma module within the Behavioral Risk Factor Surveillance System (BRFSS). Lifetime IPV was assessed by four questions that asked about threatened, attempted, or completed physical violence, as well as unwanted sex, by a current or former intimate partner. The children's asthma module asked respondents to report whether a randomly selected child in their household had ever been diagnosed with asthma and whether the same child currently had asthma. Women who experienced lifetime IPV, in contrast to women who never experienced IPV, were significantly more likely to report that their children had ever had asthma and currently have asthma. Among men, significant differences were not found when comparing men who reported lifetime IPV to those that did not report lifetime IPV. The results highlight the importance of primary prevention of IPV, as reducing the occurrence of IPV could improve not only the long-term health of those who experience IPV but also the health of their children. © 2010 John Wiley & Sons A/S. Source

Dodd Jr. C.K.,University of Florida | Hyslop N.L.,University of Florida | Hyslop N.L.,Gainesville State College | Oli M.K.,University of Florida
Chelonian Conservation and Biology | Year: 2012

Disturbances can affect the structure of ecological communities, and their impacts may have consequences for individual species' population dynamics and long-term persistence. Even without catastrophic mortality, survivorship could be reduced following a disturbance, thus leading to population decline. We used a 16-year markrecapture dataset to determine the effects of catastrophic storms and the cutting of nonindigenous vegetation on the survivorship and abundance of a population of long-lived terrestrial turtles (Terrapene bauri). Our results indicate that these habitat disturbances had little long-term effect on abundance. Indeed, the population continued to grow despite severe changes to its habitat, although recapture probabilities decreased through time. Tertiary (adult) sex ratios became more highly skewed temporarily but eventually approached their predisturbance levels. In long-lived box turtles, short-term disturbances may alter growth rates and dispersal tendencies, but they appear to have little long-term effect on abundance as long as initial mortality is not severe and food resources remain available. © 2012 Chelonian Research Foundation. Source

Lampert E.,Gainesville State College
American Biology Teacher | Year: 2011

I explain a classroom activity to model translation of RNA into proteins. Students are given worksheets with short mRNA sequences and a genetic code coding phrases instead of amino acids. Students use the code to write a sentence from their mRNA sequences; a "Chuck Norris fact" is provided as an example. 1 also provide instructions to expand this activity to include transcription of DNA into RNA. © 2011 by National Association of Biology Teachers. All rights reserved. Source

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