A current assessment of the THOR 50M in rear impacts.

OBJECTIVE: This study presents a comparison of the Test Device for Human Occupant Restraint (THOR) 50M and Hybrid III (HIII) 50M anthropomorphic test device (ATD) geometries and rear impact head and neck biofidelity to each other and to postmortem human surrogate (PMHS) data to evaluate the usefulness of the THOR in rear impact testing. METHODS: Both ATDs were scanned in a seated position on a rigid bench seat. A series of rear impact sled tests with the rigid bench seat with no head restraint support were conducted with a HIII-50M at 16 and 24 kph. Tests at each speed were performed twice with the THOR-50M to allow an assessment of the repeatability of the THOR-50M. A comparison of the test results from THOR-50M testing were made to the results of a previous study that included PMHS. Rear impact sled tests with both ATDs in a modern seat were then conducted at 40 kph. RESULTS: The THOR-50M head was 48.4 mm rearward and 60.1 mm higher than the HIII-50M head when seated in the rigid bench seat. In the repeated rigid bench testing at 16 and 24 kph, the THOR-50M head longitudinal and vertical accelerations, upper neck moment, and overall kinematics showed good test-to-test repeatability. In the rigid bench tests, the THOR-50M neck experienced flexion prior to extension in the 16 kph tests, where the neck of the HIII only experienced extension. At 24 kph both ATDs only experienced extension. The THOR-50M head displaced more rearward at both test velocities. The rigid bench tests show that the THOR-50M neck allows for more extension motion or articulation than the HIII-50M neck. The rigid bench test also shows that the head longitudinal and vertical accelerations, angular head kinematics, and upper neck moments were reasonably comparable between the ATDs. The THOR-50M results were closer to the average of the PMHS results than the HIII-50-M results, with the exception of the upper neck. In the 40 kph tests, with a modern seat design, the THOR-50M resulted in more deformation of the seatback with greater head restraint loading than the HIII-50M. The THOR-50M head backset distance was less. CONCLUSION: This study provides insight into the differences and similarities between the THOR and the HIII-50M ATD geometries, instrumentation responses, and kinematics, as well as the repeatability of the THOR-50M in rear impacts testing. The overall geometries of the THOR-50M and the HIII-50M are similar. The seated head position of the THOR-50M is slightly further rearward and higher than the HIII-50M. The results indicate that the THOR-50M matches the PMHS results more closely than the HIII-50M and may have improved neck biofidelity in rear impact testing. The results indicate that the studied THOR-50M responses are repeatable within expected test-to-test variations in rear impacts. Early data suggest that the THOR-50M can be used in rear impact testing, though a more complete understanding of the THOR-50M differences to the HIII ATDs will allow for better correlation to the existing body of HIII rear impact testing.

The effect of seatback deformation on out-of-position front-seat occupants in severe rear impacts.

OBJECTIVE: This study assesses the effects of seat deflection in severe oblique rear impacts with laterally out-of-position ATDs where the head is not supported by the head restraint. METHOD: Six high-speed rear sled tests were conducted at 48 km/h with a 195 degree PDOF. A lap-shoulder belted 50th percentile Hybrid III ATD was leaned inboard and seated in six different front passenger seats (A-F); five of the seats were selected from mid-sized sedans and one was a non-production rigidified Seat Integrated Restraint (SIR) seat. FRED-III pull tests resulted in seat stiffnesses that varied from 73 to 172 N/mm. Seat F had the greatest stiffness. The seat and ATD responses were assessed. The biomechanical responses were evaluated and compared to relevant IARVs. RESULTS: In all tests the ATD moved rearward and twisted the seat. There was limited differential motion of the torso relative to the seatback. The ATD position and PDOF prevented head restraint engagement allowing head and neck extension over the seatback. The seatback angle was measured on the inboard side. At maximum yield, it was greatest with Seat E, followed by Seat A and Seat D, at 71, 67 and 62 degrees, respectively. The duration of rearward deformation was also greatest with Seat A, Seat D and Seat E providing longer ride-down. The head, chest and upper neck responses were below IARVs. Lower-neck extension moments were above injury threshold with Seat B, C and F. Seat F had the highest lower-neck moment. CONCLUSION: Seats with greater deformation provided the greatest ride-down durations and the lowest overall biomechanical responses. The combination of high impact severity and lack of head support resulted in high lower-neck responses, highlighting the potential benefit of energy management from deforming seat structures.

Quasi-static methods to evaluate seat strength in rear impacts.

OBJECTIVE: Various methods have been used in the past 50 years to apply Quasi-static load to a seat in the rear direction and measure seat performance in rear impacts. This study compared five of the most-common test procedures to evaluate seats. In addition, occupant mass and center of gravity are discussed as important characteristics of rear loading of seats. METHOD: Data was collected and analyzed from five different seat pull tests, including FMVSS 207, modified FMVSS 207, QST, body block and FRED II. Test data included peak force, moment and angle at peak moment. Occupant loading height of was determined using body segment weights and position in the forward (x) and vertical (z) directions based on anthropometry data. RESULTS: Some of the inherent differences in the tests are shown by comparing data with the same seat structure. The QST and FRED II use a lower height of loading than FMVSS 207. The QST and FRED II peak moment and force did not coincide with the same seatback angle as in FMVSS 207 and body block testing. Center of gravity height varies depending on whether the whole body or only the upper torso is considered. For the 50th male, it is 171.5 mm (6.8") with the whole body and 246.7 mm (9.7") with the upper torso. CONCLUSION: Results from different tests cannot be readily compared because of different loading conditions, including body shape and height of load about the H-point, which can cause the seat structure to respond differently.

Evaluations of pretensioner activation in rear impacts.

OBJECTIVE: Occupant kinematics and biomechanical responses are assessed with and without pretensioning of normally seated and out-of-position front-seat occupants in rear sled tests. The results are compared to recent studies. METHODS: Three series of rear sled tests were conducted at 24 and 40 km/h with a 2001 Ford Taurus. Series I consisted of two sled tests with a lap-shoulder belted 50th Hybrid III in the driver seat. Series II included four sled tests with a lap-shoulder belted 50th Hybrid III in both front seats. Two soft foam blocks were added, one was placed on the chest centerline under the shoulder belt and one on the pelvis under the lap belt providing additional webbing. Series III consisted of 8 runs and 16 ATD tests to assess the effect of pretensioning with out-of-positioned (OOP) occupants. The biomechanical responses were normalized with Injury Assessment Reference Values (IARV) for head, neck and chest. RESULTS: The ATD kinematics and biomechanical responses were similar in the yielding phase when the occupant was normally seated with and without pretensioning. The rebound displacement was greater with pretensioning in the 40 km/h tests due to the shoulder belt slipping off the shoulder. The hip displacement was similar, irrespective of pretensioning. All biomechanical responses were below IARVs. The highest response was for lower neck extension. The normalized response was at about 32% for the 24 km/h tests, irrespective of pretensioning. It was up to 59% in the 40 km/h tests with pretensioning. With the OOP occupants, there were no differences in the kinematics and biomechanical response with pretensioning. CONCLUSIONS: Testing of the effect of retractor pretensioning with out-of-position occupants and additional belt webbing in moderate to high-speed rear sled tests shows no effect on occupant kinematics and biomechanical responses. The displacement of the hips in a rear impact depends on the compliance of the seatback and amount of pocketing, the stiffness of the seat frame limiting rearward rotation, and the dynamic friction between the occupant and the seatback.

Influence of retractor and anchor pretensioning on dummy responses in 40 km/h rear sled tests.

OBJECTIVE: This study compared dummy kinematics and biomechanical responses with and without retractor pretensioning in a severe rear sled test. It compliments an earlier study with buckle pretensioning. METHODS: Three rear tests were run at 40 km/h (25 mph) delta V with a lap-shoulder belted Hybrid III 50th male dummy on a 2013-18 Ford Escape driver seat and belt restraint. One test was with the lap-shoulder belts only, a second with retractor and anchor pretensioning and a third with only retractor pretensioning. The head, chest and pelvis were instrumented with triaxial accelerometers. The upper and lower neck, thoracic spine and lumbar spine had transducers measuring triaxial loads and moments. Lap belt load was measured. High-speed video recorded different views of the dummy motion. Dummy kinematics and biomechanical responses were compared to determine the influence of retractor belt pretensioning. RESULTS: The dummy kinematics and biomechanical responses were essentially similar with and without retractor or retractor and anchor pretensioning in rear sled tests. There was an initial spike in lap belt load with pretensioning, but it did not result in different dummy head, neck or chest responses. In the tests, the dummy moved rearward away from the shoulder belt. The belts were tightened with the rapid pull on the webbing by pretensioning. The dummy loaded the seat, which yielded rearward restraining its motion. There was no significant effect of pretensioning on the dynamics of the dummy until late in rebound. CONCLUSIONS: There were no significant differences in dynamics of the Hybrid III with and without retractor or retractor and anchor pretensioning in a 40 km/h (25 mph) rear sled test. Belt pretensioning did not influence biomechanical responses in the rear impact because the seat supported the dummy.

Effect of ABTS and conventional seats on occupant injury in rear impacts: Analysis of field and test data.

PURPOSE: This study addressed the potential effect of higher seat stiffness with ABTS (All-Belt-to-Seat) compared to conventional seats in rear impacts. It analyzed field accidents and sled tests over a wide range in delta V and estimated the change in number of injured occupants if front-seats were replaced with stiffer ABTS. METHODS: The rear-impact exposures and serious-to-fatal injury rates were determined for 15+ year old non-ejected drivers and right-front passengers in 1994+ model year vehicles using 1994-2015 NASS-CDS. More than 50 rear sled tests were analyzed using conventional and ABTS seats. An injury risk was calculated for selected ATD biomechanical responses. The results obtained with the ABTS and conventional seats were compared for matched tests based on head restraint position, ATD size and initial position and delta V. The change in risk was used to estimate the change in injury in the field by adjusting the injury rate by delta V. RESULTS: On average, front seat occupants were 39 years old, weighed 78 kg and were 171 cm tall. About 29.3% of serious-to-fatally injured (MAIS 3 + F) front seat occupants were involved in delta Vs less than 24 km/h and about 28.4% in a delta V of 48 km/h or greater. The average biomechanical response and injury risk in sled tests were higher with an ABTS seat than with a conventional seat. The average maximum injury risk was assessed by delta V groups for conventional and ABTS seats. The relative risk of ABTS to conventional seats was 1.34 in less than 16 km/h, 1.69 in 16-24 km/h, 1.65 in 24-32 km/h, 1.33 in 32-40 km/h, 5.77 in 40-48 km/h and 48.24 in the 56-64 km/h delta V category. The estimated relative risk was 11.90 in 48-56 km/h and 34.11 in 64+ km/h. The number of serious-to-fatally injured occupants was estimated to increase by up to 6.88-times if stiffer ABTS seats replaced conventional seats. CONCLUSIONS: The field data indicate that the 50th percentile male Hybrid III size is representative of an average occupant involved in rear crashes. ABTS seats used in this study are stiffer than conventional seats and increase ATD responses and injury risks over a wide range of crash severities.

Second-row occupant responses with and without intrusion in rear sled and crash tests.

PURPOSE: Intrusion of the occupant compartment increases the risks for severe injury and death. This study analyzes rear sled and crash tests with an instrumented second-row Hybrid III 5th percentile anthropometric test device (ATD) to assess occupant kinematics and biomechanical responses with and without intrusion of the second-row seatback. METHODS: Three sled tests and four crash tests were conducted with a 1993 Ford Taurus and a belted 5th female ATD seated behind a belted 50th male ATD on the right-side of the vehicle. The sled tests were conducted at 25, 33 and 40 km/h and involved no intrusion. The first crash test was conducted with a passenger car striking the vehicle at 80 km/h with full centerline overlap. The second to fourth crash tests were with a Sport Utility Vehicle (SUV) striking with a 50% overlap. Tests 2 and 3 were at 51 km/h and test 4, at 80 km/h impact speed. A large wooden speaker box was placed in the trunk of the Taurus in tests 3 and 4. Second-row intrusion was measured at the right-rear outboard package shelf retractor. RESULTS: The sled tests without intrusion had occupant responses below injury assessment reference values (IARVs). The right second-row ATD moved rearward relative to the interior, compressing the rear seatback until it rebounded forward. Occupant compartment intrusion of 12-77 cm in the crash tests pushed the ATD forward, increasing head and chest acceleration. The head, neck and chest biomechanical responses were below IARVs in crash tests 1 to 3 with minimal intrusion (≤ 25 cm). Most of the biomechanical responses were above IARVs for the right second-row ATD in test 4 with higher intrusion. The HIC increased with intrusion. Head acceleration was more than 2.5-times greater in test 3 than in test 2, highlighting the importance of cargo in rear crashes. Test 4 had 2.4-times more energy than test 3 and up to 7.7 times greater biomechanical responses with 77 cm of intrusion. CONCLUSIONS: The crash tests show that intrusion increases occupant responses in the right second-row seat and pushes the occupant forward in rear impacts. The sled tests without intrusion had relatively low biomechanical responses. Intrusion was influenced by the crash energy and cargo.

Thoracic and lumbar spine responses in high-speed rear sled tests.

OBJECTIVE: This study analyzed thoracic and lumbar spine responses with in-position and out-of-position (OOP) seated dummies in 40.2 km/h (25 mph) rear sled tests with conventional and all-belts-to-seat (ABTS) seats. Occupant kinematics and spinal responses were determined with modern (≥2000 MY), older (<2000 MY), and ABTS seats. METHODS: The seats were fixed in a sled buck subjected to a 40.2 km/h (25 mph) rear sled test. The pulse was a 15 g double-peak acceleration with 150 ms duration. The 50th percentile Hybrid III was lap-shoulder belted in the FMVSS 208 design position or OOP, including leaning forward and leaning inboard and forward. There were 26 in-position tests with 11 <2000 MY, 8 ≥2000 MY, and 7 ABTS and 14 OOP tests with 6 conventional and 8 ABTS seats. The dummy was fully instrumented. This study addressed the thoracic and lumbar spine responses. Injury assessment reference values are not approved for the thoracic and lumbar spine. Conservative thresholds exist. The peak responses were normalized by a threshold to compare responses. High-speed video documented occupant kinematics. RESULTS: The extension moments were higher in the thoracic than lumbar spine in the in-position tests. For <2000 MY seats, the thoracic extension moment was 76.8 ± 14.6% of threshold and the lumbar extension moment was 50.5 ± 17.9%. For the ≥2000 MY seats, the thoracic extension moment was 54.2 ± 26.6% of threshold and the lumbar extension moment was 49.8 ± 27.7%. ABTS seats provided similar thoracic and lumbar responses. Modern seat designs lowered thoracic and lumbar responses. For example, the 1996 Taurus had -1,696 N anterior lumbar shear force and -205.2 Nm extension moment. There was -1,184 N lumbar compression force and 1,512 N tension. In contrast, the 2015 F-150 had -500 N shear force and -49.7 Nm extension moment. There was -839 N lumbar compression force and 535 N tension. On average, the 2015 F-150 had 40% lower lumbar spine responses than the 1996 Taurus. The OOP tests had similar peak lumbar responses; however, they occurred later due to the forward lean of the dummy. CONCLUSIONS: The design and performance of seats have significantly changed over the past 20 years. Modern seats use a perimeter frame allowing the occupant to pocket into the seatback. Higher and more forward head restraints allow a stronger frame because the head, neck, and torso are more uniformly supported with the seat more upright in severe rear impacts. The overall effect has been a reduction in thoracic and lumbar loads and risks for injury.

Occupant responses in conventional and ABTS seats in high-speed rear sled tests.

OBJECTIVE: This study compared biomechanical responses of a normally seated Hybrid III dummy on conventional and all belts to seat (ABTS) seats in 40.2 km/h (25 mph) rear sled tests. It determined the difference in performance with modern (≥2000 MY) seats compared to older (<2000 MY) seats and ABTS seats. METHODS: The seats were fixed in a sled buck subjected to a 40.2 km/h (25 mph) rear sled test. The pulse was a 15 g double-peak acceleration with 150 ms duration. The 50th percentile Hybrid III was lap-shoulder belted in the FMVSS 208 design position. The testing included 11 <2000 MY, 8 ≥2000 MY, and 7 ABTS seats. The dummy was fully instrumented, including head accelerations, upper and lower neck 6-axis load cells, chest acceleration, thoracic and lumbar spine load cells, and pelvis accelerations. The peak responses were normalized by injury assessment reference values (IARVs) to assess injury risks. Statistical analysis was conducted using Student's t test. High-speed video documented occupant kinematics. RESULTS: Biomechanical responses were lower with modern (≥2000 MY) seats than older (<2000 MY) designs. The lower neck extension moment was 32.5 ± 9.7% of IARV in modern seats compared to 62.8 ± 31.6% in older seats (P =.01). Overall, there was a 34% reduction in the comparable biomechanical responses with modern seats. Biomechanical responses were lower with modern seats than ABTS seats. The lower neck extension moment was 41.4 ± 7.8% with all MY ABTS seats compared to 32.5 ± 9.7% in modern seats (P =.07). Overall, the ABTS seats had 13% higher biomechanical responses than the modern seats. CONCLUSIONS: Modern (≥2000 MY) design seats have lower biomechanical responses in 40.2 km/h rear sled tests than older (<2000 MY) designs and ABTS designs. The improved performance is consistent with an increase in seat strength combined with improved occupant kinematics through pocketing of the occupant into the seatback, higher and more forward head restraint, and other design changes. The methods and data presented here provide a basis for standardized testing of seats. However, a complete understanding of seat safety requires consideration of out-of-position (OOP) occupants in high-speed impacts and consideration of the much more common, low-speed rear impacts.

Influence of a combo side airbag on the risk for basilar skull fracture in a far-side occupant.

OBJECTIVE: The impact force to the head and neck were measured in sled tests with and without inflation of a combo airbag for a far-side occupant to determine the risk for basilar skull fracture. METHODS: Sled tests were run at 24 and 32 km/h (15 and 20 mph) with and without inflation of a combo side airbag to analyze the effect of cross-car diving into the side interior. The matched tests involved one pair at 24 km/h and another at 32 km/h. The 24 km/h pair involved a lap-shoulder-belted 5th percentile female Hybrid III and the series at 32 km/h involved an unbelted 5th percentile Hybrid III. The dummy was ballasted to 69.5 kg (153 lb) and laid on the right side. The dummy was positioned 30.5 cm (12(″)) from the far-side interior to ensure the full sled delta V occurred before head impact. The buck consisted of a 2001 Ford Taurus. The combo thorax-head side airbag was stored in the seatback. The airbag was triggered about 120 ms before the head impact. The head, chest, and pelvis were instrumented with triaxial accelerometers and the upper and lower neck, thoracic spine, and lumbar spine had transducers measuring triaxial loads and moments. High-speed video recorded different views of the dummy motion. Dummy kinematics and biomechanical responses were compared to study the influence of inflating the side airbag on the head and neck. RESULTS: The top of the head impacted the far side. The force of impact was similar with and without the airbag as the head compressed the airbag and loaded the vehicle interior trim behind the airbag. The peak force on the head was primarily from neck load as torso augmentation occurred. For the 24 km/h (15 mph) tests, the peak force was 4.7 kN (1055 lb) without and 4.8 kN (1088 lb) with the airbag and there was over 2.67 kN (600 lb) of lap belt load. The peak head acceleration was 93 g without and 72 g with the airbag. For the 32 km/h (20 mph) tests, the force on the head was 15.3 kN (3433 lb) without and 15.2 kN (3406 lb) with the airbag, although the instrumentation saturated. The peak head acceleration was 236 g without and 262 g with the airbag. CONCLUSION: The airbag reduced head acceleration in the belted test but did not influence the diving forces from torso augmentation through the neck of the far-side occupant. The side airbag did not reduce the risk for basilar skull fracture due to high neck compression loads in either the belted or unbelted tests.

Rebound after rear impacts.

OBJECTIVE: A number of field accident studies have found that rebound is a source for occupant injury after rear impacts. Sled tests were run to investigate occupant kinematics and rebound, including head velocity and displacement with 3 different seats, 2 conventional seat designs, and 1 all belts to seat (ABTS). METHODS: Nine rear-end sled tests were run with a belted 50th Hybrid III dummy on a Taurus, Mustang, or Sebring ABTS seat in nominally 16.5, 24.1, and 32.5 km/h rear-end delta Vs. There was no sled braking after the rear acceleration to study rebound from the seat. Dummy kinematics were analyzed from high-speed video and biomechanical responses from triaxial head and chest accelerations, triaxial upper and lower neck loads and moments, and seat belt loads. Peak responses were tabulated during seat back rotation rearward and rebound forward. Ratios of biomechanical and kinematic responses were determined comparing ABTS to conventional seat responses for each delta V. Student's t-test was used to determine significant differences between the ratios of ABTS to conventional seat responses. RESULTS: The rebound velocity of the head varied from 2.9 to 6.8 m/s with respect to the sled. Overall, it was 69 ± 22 percent higher than the sled delta V. It was greatest with ABTS in the highest severity test where seat back yielding absorbed energy and reduced rebound in the conventional seats. The time to maximum forward excursion was significantly shorter with ABTS compared to the conventional seats with a ratio of 0.54 ± 0.34 (t = 6.13, df = 5, P < .001). CONCLUSIONS: ABTS seats remain more upright in rear-end crashes and transfer greater load to the occupant during rebound than conventional seats that yield rearward and absorb energy in higher severity crashes. Rebound occurs earlier and at higher velocities with ABTS. This displaces the occupant toward the front interior. Supplemental materials are available for this article. Go to the publisher's online edition of Traffic Injury Prevention to view the supplemental file.

Proliferative and nonproliferative lesions of the rat and mouse urinary system.

The INHAND Project (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP), and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature for classifying lesions observed in the urinary tract of rats and mice. The standardized nomenclature of urinary tract lesions presented in this document is also available electronically on the Internet (http://www.goreni.org/). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous developmental and aging lesions as well as those induced by exposure to test materials. A widely accepted and utilized international harmonization of nomenclature for urinary tract lesions in laboratory animals will decrease confusion among regulatory and scientific research organizations in different countries and provide a common language to increase and enrich international exchanges of information among toxicologists and pathologists.

Influence of belt pretensioning on dummy responses in 40 km/h rear-impact sled tests.

OBJECTIVE: This study compares dummy kinematics and biomechanical responses with and without belt pretensioning in matched rear sled tests. METHODS: Two rear-impact sled tests were run at 40 km/h (25 mph) rear delta V with a lap-shoulder-belted Hybrid III 50th percentile male dummy on Ford F-150 driver seats. One test was with the standard lap-shoulder belts and the other with a buckle pretensioner activated at 20 ms. The head, chest, and pelvis were instrumented with triaxial accelerometers. The upper and lower neck, thoracic spine, and lumbar spine had transducers measuring triaxial loads and moments. Lap and shoulder belt loads were measured. High-speed video recorded different views of the dummy motion. Dummy kinematics and biomechanical responses were compared to study the influence of belt pretensioning. RESULTS: The dummy kinematics and biomechanical responses were essentially similar with and without belt pretensioning in the rear-impact sled tests. There were higher belt loads with pretensioning, but they did not result in different dummy lumbar loads or pelvic, chest, and head accelerations. In a rear impact, the dummy moves rearward away from the belts that wrap around the chest and pelvis. The occupant loads the seat, which yields rearward restraining dummy motion. Though pretensioning caused a transient increase in belt load, it was of short duration and there was no sustained effect on occupant dynamics until late in rebound. CONCLUSIONS: The matched tests showed no difference in occupant restraint with and without buckle pretensioning in 40 km/h (25 mph) rear-impact sled tests. Belt pretensioning did not influence occupant responses in these rear impacts because the seat supported the occupant.

Influence of standing or seated pelvis on dummy responses in rear impacts.

OBJECTIVE: There is a question whether the standing or seated pelvis should be used in Hybrid III dummy evaluations of seats and belt restraint systems in severe rear impacts. This study compares the standing and seated Hybrid III pelvis in matched rear sled tests. METHODS: Sixteen sled tests were found at 10, 16 and 24 km/h rear delta V in Ford's archives where matched tests were run with the standing and seated pelvis in a belted Hybrid III dummy. Two new tests were conducted at 40 km/h rear delta V to extend the severity range. The head, chest and pelvis were instrumented with triaxial accelerometers and the upper and lower neck, thoracic spine and lumbar spine had transducers measuring triaxial loads and moments. Belt Loads were measured. High-speed video recorded different views of the dummy motion. Dummy kinematics and biomechanical responses were compared for all of the data with the two different Hybrid III pelvic designs. RESULTS: In the 40 km/h sled tests, the dummy motion and excursion were essentially similar with the standing and seated pelvis. The similarities included the lap belt interaction with the pelvis and the leg movement upward flexing the hip joint. Overall, similar biomechanic and kinematic responses were found, including the pelvic acceleration, spinal forces and moments. For the lower speed tests at 10, 16 and 24 km/h, the motion sequence was also similar with the two different pelvises, including the upward movement of the legs as the seat was loaded and rebound kinematics. The biomechanical responses were similar. The seated pelvis involves only a small portion of the upper leg molded into the vinyl skin of the pelvis and does not limit leg rotation at the hip joint. Furthermore, lap belt loads were minimal during the rearward movement of the dummy. CONCLUSIONS: The matched testing showed no significant difference in occupant kinematics or biomechanical responses between the standing and seated pelvis in rear sled tests. The Hybrid III dummy with the seated pelvis is suitable for FMVSS 301 and other testing of seats and belt restraint systems in severe rear impacts.

IFNalpha kinoid vaccine-induced neutralizing antibodies prevent clinical manifestations in a lupus flare murine model.

A major involvement of IFNalpha in the etiopathogenesis of systemic lupus erythematosus has been suggested by clinical observations, including the increase of serum levels of this cytokine in patients with active disease. Supporting this hypothesis, we have shown that expression of IFNalpha from a recombinant adenovirus (IFNalpha Adv) precipitates lupus manifestations in genetically susceptible New Zealand Black (NZB) x New Zealand White (NZW)F(1) mice (NZB/W) but not in BALB/c mice. In the present investigation, we have prepared an IFNalpha immunogen, termed IFNalpha kinoid, which, appropriately adjuvanted, induces transient neutralizing antibodies (Abs) but no cellular immune response to the cytokine and without apparent side effects. Using this preparation, we also showed that, in kinoid-vaccinated NZB/W mice, lupus manifestations, including proteinuria, histological renal lesions, and death triggered by IFNalpha Adv challenge were delayed/prevented as long as an effective threshold of anti-IFNalpha inhibitory capacity was present in the serum.

Histopathological lesions following intramuscular administration of saline in laboratory rodents and rabbits.

This review was undertaken to assess the nature and incidence of procedure-related changes in mice, rats and rabbits which received saline solution by intramuscular injection. Data were collected on the injection sites from 7 studies representing 152 animals. The original observations by the different study pathologists from both control and treated animals were evaluated in order to create a glossary of preferred terms to be used in toxicology studies. These standardized terms were then applied to changes observed in the saline-treated animals. The review showed that the most severe of the procedure-related lesions were only of a slight level. Two days post-injection, the local reactions were mainly composed of minimal infiltration by mononuclear cells (lymphocytes and macrophages) with occasional degeneration of myofibres. From 10 to 42 days post-injection, lesions showed regeneration of myofibres and some fibrosis. In rats, the number of injections at each site influenced inflammatory infiltrate and degenerative lesions.

Seat integrated and conventional restraints: a study of crash injury/fatality rates in rollovers.

This study used police-reported motor vehicle crash data from eleven states to determine ejection, fatality, and fatal/serious injury risks for belted drivers in vehicles with conventional seatbelts compared to belted drivers in vehicles with seat integrated restraint systems (SIRS). Risks were compared for 11,159 belted drivers involved in single- or multiple-vehicle rollover crashes. Simple driver ejection (partial and complete), fatality, and injury rates were derived, and logistic regression analyses were used to determine relative contribution of factors (including event calendar year, vehicle age, driver age/gender/alcohol use) that significantly influence the likelihood of fatality and fatal/serious injury to belted drivers in rollovers. Results show no statistically significant difference in driver ejection, fatality, or fatal/serious injury rates between vehicles with conventional belts and vehicles with SIRS.

Variability in weight and histological appearance of the prostate of beagle dogs used in toxicology studies.

This review was performed to assess variations in weight and histologic appearance of the prostate of untreated male beagle dogs between 23 and 108 weeks of age, from two breeding centers. Data from 125 control beagle dogs from twenty-seven regulatory toxicology studies were used. Age, terminal body weight, and prostate weight were analyzed. Prostate sections were examined microscopically, and histological changes-such as development of acini, amount of secretion, and patterns of dilation and inflammation-were recorded and graded when appropriate. The influence of age, terminal body weight, and source on the weight and histological appearance of the prostate, and the degree of interanimal variation were evaluated.

Large-scale purification and crystallization of adenovirus hexon.

This chapter provides a protocol for the large-scale purification of adenovirus type 2 and 5 virions and the soluble major coat protein hexon. The purified virus particles remain intact and are suitable for vector, vaccine, or structural studies and can also be used as seed stock for further rounds of infection. The hexon may be used to produce crystals suitable for high-resolution X-ray crystallographic studies. Briefly, virus is propagated in HeLa cell suspension cultures. The infected cells are lysed, virions and hexon are separated by centrifugation, and the protein is then further purified by anion exchange chromatography. The entire purification procedure takes approx 1 wk and typically yields 10(13) virus particles and 10-20 mg of highly purified hexon.

Nanoporous crystals of chicken embryo lethal orphan (CELO) adenovirus major coat protein, hexon.

CELO (chicken embryo lethal orphan) virus is an avian adenovirus that is being developed as a gene transfer vector. Its trimeric major coat protein (942 residues, 106,709 Da) has 42% sequence identity to human adenovirus type 2 (AdH2) hexon and 45% to AdH5 hexon. For structural studies, the growth of CELO virus has been optimized, and its hexon purified and crystallized. The hexon crystals, the first non-human example, diffract to 3.9 A resolution. Molecular replacement using the AdH5 model was used to identify the location of the CELO hexon within the unit cell. There is one hexon monomer in the asymmetric unit of the trigonal space group P321 (a=b=157.8 A, c=114.2 A, gamma=120 degrees) and the solvent content is 67.8%. The hexons pack in a hexagonal honeycomb so that large approximately 100 A diameter channels run through the entire crystal. This remarkable property of the crystals lends itself to their exploitation as a nanomaterial. Structural studies on CELO will elucidate the differences between avian and human adenoviruses and contribute to a better understanding of adenoviruses with non-human hosts.