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The purpose of the study was to distinguish the role of vehicle structure in frontal impacts in published coded National Automotive Sampling System (NASS-CDS) data. The criteria used: Collision Deformation Classification (CDC) coding rules, crush profile locator data and the projected location of longitudinal structural members in models of vehicle class sizes used by NASS-CDS. Two classifiers were developed to augment the CDC system. The Coincidence classifier indicates the relationship between the quadrant of the clock face the crash vector originates in and the aspect of the end plane the center of damage is located. It has three values: Linear (12 o'clock impacts) Consistent and Variant ("oblique" Principal Directions of Force or PDOFs). The second classifier indicates the number of longitudinal members engaged: 0, 1 or 2. NASS-CDS data for sample years 2005 to 2009 was filtered for occupants involved in impacts with the highest ranked speed change assigned to the front-end plane.

In 1989, the EUROSID-1 was accepted in the European regulation ECE-R95. After a steady period of use, an upgraded version of this dummy: ES-2 is now considered as a step towards harmonization of side impact occupant regulations. The upgrades to the dummy include, amongst others, a modification of its torso back plate and a change in rib module guidance (piston-cylinder), especially to overcome anomalous rib deflection responses referred to as ""flat-top.'' Presented here are results of lateral and oblique pendulum tests, conducted on the EUROSID-1 and ES-2 to verify the modified torso back plate and to study the responses of three proposed rib module designs for ES-2. Particularly, rib deflections, rib VC responses, and thorax force-deflection responses are analyzed. The current study primarily addresses sensitivity of the ES-2 thorax to oblique loading.

Space flight and related factors such as stress appear to have an adverse effect on astronauts' immune systems. The presence of potentially pathogenic microbes including several genera of fungi reported from spacecraft environment may be a cause of concern in such situations. In order to study the role of such organisms in causing opportunistic or allergic diseases in crewmembers, we have tried to develop an animal model. BALB/c mice were suspended upside down for varying periods of time to induce stress, and their lymphocyte functions were evaluated. These studies indicate that the stress resulted in lowered mitogen induced lymphocyte stimulation as represented by 3H-thymidine uptake. We have also studied the ability of these animals to respond to Aspergillus fumigatus spores. The results of the study clearly demonstrate a definite down-regulation in T-cell proliferation and a higher incidence of infection with A. fumigatus.

The objective of the study was to investigate the biomechanical response of the intact cranium. Unembalmed human cadavers were used in the study. The specimens were transected at the base of the skull leaving the intracranial contents intact; x-ray and computed tomography (CT) scans were obtained. They were fixed in a specially designed frame at the auditory meatus level and placed on the platform of an electrohydraulic testing device via a six-axis load cell. Following radiography, quasistatic loading to failure was applied to one of the following sites: frontal, vertex, parietal, temporal, or occipital. Retroreflective targets were placed in two mutually orthogonal planes to record the localized temporal kinematics. Applied load and piston displacement, and the output generalized force (and moment) histories were recorded using a modular digital data acquisition system. After the test, x-ray and CT images were obtained, and defleshing was done.

Head injury is a serious threat to lives of people working around farm machinery. The consequence of head injuries are costly, paralytic, and often fatal. Clinical and biomechanical data on head injuries are reviewed and their application in the analysis of head injury risk associated with farm tractor discussed. A significant proportion of tractor-related injuries and deaths to adults, as well as children, is due directly or indirectly to head injury. An improved injury reporting program and biomechanical studies of human response to tractor rollover, runover, and falls, are needed to understand mechanisms of the associated head injury.

In the present investigation a tractor wheel runover accident was simulated to obtain biomechanical information relating to mechanism of injury. Twelve cadaver porcine specimens were runover with the right front wheel of a tractor. Specimens were placed on a six-axis force plate and thorax contours were recorded temporally. Results indicated up to 68% compression of the chest occurred during the runover event. The shear force in the direction of travel was a significant factor in the type of fractures that occurred to the rib cage. Pathology determined from x-ray revealed multiple fractures per rib in the area directly below the path of the tire. Autopsy evaluation revealed soft tissue contusion on the left side in the area of wheel path. There was often extra blood in the pericardial space and examination of the brain showed petechial hemorrhaging subdurally.

Oblique crashes to the vehicle front corner may not be characteristic of either frontal or side impacts. This research evaluated occupant response in oblique crashes for a driver, rear adult passenger, and a rear child passenger. Occupant responses and injury potential were evaluated for seating positions as either a far-or near-side occupant. Two crash tests were conducted with a subcompact car. The vehicle’s longitudinal axis was oriented 45 degrees to the direction of travel on a moving platform and pulled into a wall at 56 km/h. Dummies utilized for the seating positions were an adult dummy (50th-percentile-HIII and THOR-Alpha) for the front-left (driver) position, 5th-percentile-female-HIII for the right-rear position, and a 3-year-old HIII for the left-rear position.

The objective of this study was to subject small female and large male cadavers to simulated rear impact, document soft-tissue injuries to the neck, determine the kinematics, forces and moments at the occipital condyles, and evaluate neck injury risks using peak force, peak tension and normalized tension-extension criteria. Five unembalmed intact human cadavers (four small females and one large male) were prepared using accelerometers and targets at the head, T1, iliac crest, and sacrum. The specimens were placed on a custom- designed seat without head restraint and subjected to rear impact using sled equipment. High-speed cameras were used for kinematic coverage. After the test, x-rays were obtained, computed tomography scans were taken, and anatomical sections were obtained using a cryomicrotome. Two female specimens were tested at 4.3 m/s (mean) and the other two were tested at 6.8 m/s (mean), and one large male specimen was subjected to 6.6 m/s velocity.

During certain events such as underbody blasts due to improvised explosive devices, occupants in military vehicles are exposed to inferior-to-superior loading from the pelvis. Injuries to the pelvis-sacrum-lumbar spine complex have been reported from these events. The mechanism of load transmission and potential variables defining the migration of injuries between pelvis and or spinal structures are not defined. This study applied inferior-to-superior impacts to the tuberosities of the ischium of supine-positioned five post mortem human subjects (PMHS) using different acceleration profiles, defined using shape, magnitude and duration parameters. Seventeen tests were conducted. Overlay temporal plots were presented for normalized (impulse momentum approach) forces and accelerations of the sacrum and spine.

This study was conducted to quantify intracranial biomechanical responses and external blast overpressures using physical head model to understand the biomechanics of blast traumatic brain injury and to provide experimental data for computer simulation of blast-induced brain trauma. Ellipsoidal-shaped physical head models, made from 3-mm polycarbonate shell filled with Sylgard 527 silicon gel, were used. Six blast tests were conducted in frontal, side, and 45° oblique orientations. External blast overpressures and internal pressures were quantified with ballistic pressure sensors. Blast overpressures, ranging from 129.5 kPa to 769.3 kPa, were generated using a rigid cannon and 1.3 to 3.0 grams of pentaerythritol tetranitrate (PETN) plastic sheet explosive (explosive yield of 13.24 kJ and TNT equivalent mass of 2.87 grams for 3 grams of material).

Injury assessment reference values (IARV) predicting neck injuries are currently not available for side facing seated aircraft passengers in crash conditions. The aircraft impact scenario results in inertial loading of the head and neck, a condition known to be inherently different from common automotive side impact conditions as crash pulse and seating configurations are different. The objective of this study is to develop these IARV for the European Side Impact Dummy-2 (ES-2) previously selected by the US-FAA as the most suitable ATD for evaluating side facing aircraft seats. The development of the IARV is an extended analysis of previously published PMHS neck loads by identifying the most likely injury scenarios, comparing head-neck kinematics and neck loads of the ES2 versus PMHS, and development of injury risk curves for the ES2. The ES2 showed a similar kinematic response as the PMHS, particularly during the loading phase.

While numerous studies have been conducted to determine side impact responses of Post Mortem Human Surrogates (PMHS) using sled and other equipment, experiments using the biological surrogate in modern full-scale vehicles are not available. The present study investigated the presence of oblique loading in moving deformable barrier and pole tests. Three-point belt restrained PMHS were positioned in the left front and left rear seats in the former and left front seat in the latter condition and tested according to consumer testing protocols. Three chestbands were used in each specimen (upper, middle and lower thorax). Accelerometers were secured to the skull, shoulder, upper, middle and lower thoracic vertebrae, sternum, and sacrum. Chestband signals were processed to determine magnitudes and angulations of peak deflections. The magnitude and timing of various signal peaks are given. Vehicle accelerations, door velocities, and seat belt loads are also given.

The purpose of this study was to determine neck strength characteristics of children indirectly using scaling relationships through a caprine animal model. Because of the necessity to evaluate airbag designs for injury risk to the out- of-position child, a strong foundation of experimental data is needed to obtain appropriate tolerance values. Cadaver caprine cervical spines of different ages were tested mechanically in non-destructive bending and destructive tensile modes. Injuries induced in destructive testing such as endplate failure and ligament tears were consistent with clinical observations. Specimens demonstrated statistically significant increased strength characteristics with age. Scaling relationships were developed with respect to the adult specimens. For the tensile failure load the scaling percentages were 78%, 38%, 20%, and 12% for the twelve-, six-, three-, and one-year-old, respectively.

Forty-two side impact cadaver sled tests were conducted at 24 and 32 km/h impact speeds into rigid and padded walls. The post-mortem human subjects were instrumented with accelerometers on the ribs and spine and chest bands around the thorax and abdomen to characterize their mechanical response during the impact. Load cells at the wall measured the impact force at the level of the thorax, abdomen, pelvis, and lower extremities. The resulting injuries were determined through detailed autopsy and radiography. Rib fractures with or without associated hemo/pneumo thorax or flail chest were the most common injury with severity ranging from AIS=0 to 5. Full and half thorax deflections were computed from the chest band data. The cadaver test data was analyzed using ANOVA and logistic regression. The age of the subject at the time of death had influence on injury outcome while gender and mass of the subject had little or no influence on injury outcome.

Lower cervical spine injuries are more common in survivors of motor vehicle crashes sustaining neck trauma. Injury criteria are determined using upper neck loads in dummies although a lower neck load cell exists. Due to a paucity of lower neck data from post mortem human subject (PMHS) studies, this research was designed to determine the head-neck biomechanics with a focus on lower neck metrics and injuries. Sixteen frontal impact tests were conducted using five belted PMHS. Instrumentation consisted of a pyramid-shaped nine accelerometer package on the head, tri-axial accelerometer on T1, and uniaxial accelerometer on the sled. Three-dimensional kinematics of the head-neck complex were obtained using a 20-camera high-speed motion analysis system. Testing sequence was: low (3.6 m/s), medium (6.9 m/s), repeat low, and high (15.8 m/s) velocities. Trauma evaluations were made between tests. Testing was terminated upon confirmation of injuries.