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At least 73 records · Page 4Linked to original sources
PubMed2004

Linking crime guns: the impact of ballistics imaging technology on the productivity of the Boston Police Department's Ballistics Unit.

Ballistics imaging technology has received national attention as a potent tool for moving the law enforcement response to violent gun criminals forward by linking multiple crime scenes to one firearm. This study examines the impact of ballistics imaging technology on the productivity of the Boston Police Department's Ballistics Unit. Using negative binomial regression models to analyze times series data on ballistics matches, we find that ballistics imaging technology was associated with a more than sixfold increase in the monthly number of ballistics matches made by the Boston Police Department's Ballistics Unit. Cost-effectiveness estimates and qualitative evidence also suggest that ballistics imaging technology allows law enforcement agencies to make hits that would not have been possible using traditional ballistics methods.

Boston↗
PubMedDate not supplied

[Suicidal shot in the mouth with a rubber shot shell].

The purpose of weapons designed for self-defence and their ammunition is to allow effective defence without causing serious injury provided that the recommended minimum firing distance is observed. However, close-range and contact shots to vulnerable body regions may cause severe or even fatal injuries. The authors report on a suicide who fired a fatal shot in his mouth with a weapon for self-defence. The weapon used was a double-barrelled SAPL break-action gun, mod. GC 54, from which a Mini Gomm-Cogne, cal. 12/50 rubber shot shell was fired. The wound findings and ballistic characteristics of the weapon are presented and discussed.

Brain Injuries↗
PubMed2006

Experimental model for civilian ballistic brain injury biomechanics quantification.

Biomechanical quantification of projectile penetration using experimental head models can enhance the understanding of civilian ballistic brain injury and advance treatment. Two of the most commonly used handgun projectiles (25-cal, 275 m/s and 9 mm, 395 m/s) were discharged to spherical head models with gelatin and Sylgard simulants. Four ballistic pressure transducers recorded temporal pressure distributions at 308kHz, and temporal cavity dynamics were captured at 20,000 frames/second (fps) using high-speed digital video images. Pressures ranged from 644.6 to -92.8 kPa. Entry pressures in gelatin models were higher than exit pressures, whereas in Sylgard models entry pressures were lower or equivalent to exit pressures. Gelatin responded with brittle-type failure, while Sylgard demonstrated a ductile pattern through formation of micro-bubbles along projectile path. Temporary cavities in Sylgard models were 1.5-2x larger than gelatin models. Pressures in Sylgard models were more sensitive to projectile velocity and diameter increase, indicating Sylgard was more rate sensitive than gelatin. Based on failure patterns and brain tissue rate-sensitive characteristics, Sylgard was found to be an appropriate simulant. Compared with spherical projectile data, full-metal jacket (FMJ) projectiles produced different temporary cavity and pressures, demonstrating shape effects. Models using Sylgard gel and FMJ projectiles are appropriate to enhance understanding and mechanisms of ballistic brain injury.

Biomechanical Phenomena↗
PubMed2005

Quantum chemical, ballistic and explosivity calculations on 2,4,6,8-tetranitro-1,3,5,7-tetraaza cyclooctatetraene: a new high energy molecule.

Ab initio molecular orbital calculations have been carried out on 2,4,6,8-tetranitro-1,3,5,7-tetraazacyclooctatetraene, the tetramer of the series (NO(2)CN)(n) where n=1-4, using the Hartree-Fock theory with the 6-31 G(d) basis set. These calculations yield three conformers for the tetramer with D(4h), C(4h) and C(2) symmetries. The nonplanar conformer with the C(2) symmetry turns out to be 99.0 and 164.4kJmol(-1), respectively, lower in energy than the C(4h) and D(4h) conformers. The electron density topography - the density at the bond critical point - has been used as a measure of the CNO(2) strengths. Based on these bond strengths, heats of formation [obtained from the parametric model 3 (PM3) method] and specific decomposition energies, it may be concluded that (NO(2)CN)(4) is a promising candidate in the class of high energy molecules. Theoretically computed explosive (velocity of detonation, detonation pressure, etc.) and ballistic (characteristic velocity, specific impulse, etc.) parameters support these conclusions.

Electrons↗
PubMed2004

Ballistic impact to the forehead, zygoma, and mandible: comparison of human and frangible dummy face biomechanics.

BACKGROUND: Currently, there is a greater use of nonlethal force in law enforcement and military operations. Because facial injuries have been observed, there is a need to understand the human response to ballistic impacts involving various regions of the face. This study aimed to establish blunt ballistic response corridors for high-speed, low-mass facial impacts to the forehead, zygoma, and mandible, and to determine how these responses compare with those of the frangible Hybrid III headform. Correlation of the human and dummy responses allows injury risk assessment for munitions used in the field. METHODS: Facial impacts to the forehead, zygoma, and mandible of six cadavers at 42 +/- 10 m/sec were conducted using a 25- to 35-g projectile 37 mm in diameter that was instrumented with an accelerometer to determine impact force. High-speed video analysis determined penetration of the projectile, and autopsy determined the facial fractures. Force and deflection were normalized for the 50% tile response, and corridors were determined for blunt ballistic impacts. Similar tests were conducted on the frangible face of the Hybrid III dummy. RESULTS: Peak normalized force of 3.5 +/- 0.9 kN on the forehead and 3.0 +/- 1.0 kN on the mandible did not result in fractures, whereas an impact force of 2.3 +/- 0.5 kN on the zygoma caused anterior maxilla fractures. The frangible Hybrid III face developed similar force levels, but with less penetration of the projectile. Its stiffness was 43% greater than that of the cadaver. CONCLUSIONS: Higher impact force can be tolerated on the forehead and mandible than on the zygoma. Normalized force-deflection and force-time corridors were established for the human response. The frangible Hybrid III face is an effective surrogate for assessing ballistic injury risks, but greater compliance would make it more biofidelic. Initial human tolerance levels of 6.0 kN for the forehead, 1.6 kN for the zygoma, and 1.9 kN for the mandible have been established for ballistic impacts to the face.

Aged↗
PubMedDate not supplied

The management of ballistic trauma: an infection control perspective.

This article discusses the relationship between ballistic trauma, clostridial contamination and potential wound infection and considers the implications for care by nurses and infection control teams. An overview of ballistics is presented followed by an examination of the pathophysiology of wounding and its effects. The philosophy of war surgery is balanced against civilian concepts and the differing management strategies that prevail. It explores the causes of, and relationship between, wound contamination and the seriousness of wound infection. Nurses, inexperienced in dealing and caring for these types of patients, should be aware and understand the beliefs, arguments and controversies that surround ballistic trauma management. By so doing, nurses and infection control teams will be able to provide an enhanced level of holistic nursing care.

Adaptation, Psychological↗
PubMed2005

Brain injuries caused by spherical bolts.

OBJECT: Metallic particles contained in antihuman bombs increase the number of fatalities. The ballistics of these particles depends on the explosive that is used, the distance from the explosion, the shape of the particle projected, and the biomechanics of the injured tissue. The authors present their experience with penetrating spherical bolt injuries to the brain. METHODS: The authors retrospectively reviewed clinical and radiological data obtained in eight patients with penetrating spherical bolt injuries to the cranium: four had Glasgow Coma Scale (GCS) scores less than 8 (three died, one from an unrelated injury) and four had a GCS score of 15 (all survived). Two of the latter patients suffered unique anatomical injuries attributed to the distinctive ballistics of spherical bolts: in one patient the bolt penetrated the cavernous sinus causing minimal cranial nerve injury, and in the other patient the bolt lodged in the fourth ventricle causing acute hydrocephalus without other neurological deficits. CONCLUSIONS: Penetrating spherical bolts to the brain may be lethal. Nevertheless, they have unique ballistics that cause highly delineated anatomical damage and minor neurological deficits.

Adolescent↗
PubMed2004

Reference ballistic imaging database performance.

Ballistic imaging databases allow law enforcement to link recovered cartridge cases to other crime scenes and to firearms. The success of these databases has led many to propose that all firearms in circulation be entered into a reference ballistic image database (RBID). To assess the performance of an RBID, we fired 4200 cartridge cases from 600 9mm Para Sig Sauer model P226 series pistols. Each pistol fired two Remington cartridges, one of which was imaged in the RBID, and five additional cartridges, consisting of Federal, Speer, Winchester, Wolf, and CCI brands. Randomly selected samples from the second series of Remington cartridge cases and from the five additional brands were then correlated against the RBID. Of the 32 cartridges of the same make correlated against the RBID, 72% ranked in the top 10 positions. Likewise, of the 160 cartridges of the five different brands correlated against the database, 21% ranked in the top 10 positions. Generally, the ranking position increased as the size of the RBID increased. We obtained similar results when we expanded the RBID to include firearms with the same class characteristics for breech face marks, firing pin impressions, and extractor marks. The results of our six queries against the RBID indicate that a reference ballistics image database of new guns is currently fraught with too many difficulties to be an effective and efficient law enforcement tool.

Databases, Factual↗
PubMed2004

Development of biomechanical response corridors of the thorax to blunt ballistic impacts.

Human responses are critical to understanding injury biomechanics in blunt ballistic impacts, which are defined as 20-200 g projectiles impacting at 20-250 m/s. 13 human cadavers were exposed to three distinct ballistic impacts of the chest to determine force-time, deflection-time and force-deflection responses. Comparisons were made between biomechanical responses for ballistic impacts and those previously reported for lower speed, higher mass impacts. Impact condition B (140 g at 40 m/s) gave the largest peak force 10,602+/-2226 N and deflection 54.7+/-14.6 mm. Impact condition A (140 g at 20 m/s) involved lower impact energy and produced lower peak force 3383+/-761 N and deflection 25.9+/-3.1 mm, as did impact condition C (40 g at 60 m/s), which gave 3158+/-309 N and 20.1+/-7.8 mm. The results indicate each impact condition gives distinctive responses, which differ from those previously reported in the automotive literature for lower speed impacts. This information provides the foundation for future biomechanical research in the area of blunt ballistic impacts, specifically the development of test surrogates and evaluation of protective equipment.

Aged↗
PubMed2003

Reconstruction of the angle of shot by using computed radiography of the head.

In a case of murder by a single .22 caliber bullet fragmented in the head, determination of the trajectory was a key issue in identifying which of 2 windows, 1 of which was associated with 2 suspects, was the site of fire. For this purpose, we processed the computed tomography of the victim's head by using a radiation therapy planning system called Plato, which is routinely used in radiation oncology. This tool provided a 3-dimensional reconstruction of the cranio-cerebral lesions and a spatial location of bullet and bone fragments. In this article is described the more intuitive relationship with forensic and ballistic data obtained from the 3-dimensional visualization and the physical and mathematical analysis used to calculate the angle of shot.

Fatal Outcome↗
PubMed2005

Physics, ballistics, and psychology: a history of the chronoscope in/as context, 1845-1890.

In Wilhelm Wundt's (1832-1920) Leipzig laboratory and at numerous other research sites, the chronoscope was used to conduct reaction time experiments. The author argues that the history of the chronoscope is the history not of an instrument but of an experimental setup. This setup was initially devised by the English physicist and instrument maker Charles Wheatstone (1802-1875) in the early 1840s. Shortly thereafter, it was improved by the German clockmaker and mechanic Matthäus Hipp (1813-1893). In the 1850s, the chronoscope was introduced to ballistic research. In the early 1860s, Neuchâtel astronomer Adolphe Hirsch (1830-1901) applied it to the problem of physiological time. The extensions and variations of chronoscope use within the contexts of ballistics, physiology, and psychology presented special challenges. These challenges were met with specific attempts to reduce the errors in chronoscopic experiments on shooting stands and in the psychological laboratory.

Electromagnetic Phenomena↗
PubMed2004

A simplified model for the assessment of the impact probability of fragments.

A model was developed for the assessment of fragment impact probability on a target vessel, following the collapse and fragmentation of a primary vessel due to internal pressure. The model provides the probability of impact of a fragment with defined shape, mass and initial velocity on a target of a known shape and at a given position with respect to the source point. The model is based on the ballistic analysis of the fragment trajectory and on the determination of impact probabilities by the analysis of initial direction of fragment flight. The model was validated using available literature data.

Accidents, Occupational↗
PubMed2005

Ballistic variables and tissue devitalisation in penetrating injury--establishing relationship through meta-analysis of a number of pig tests.

BACKGROUND: Assessment of the injury potential is central to ascertaining that a law enforcement bullet does not cause unjustified and excessive injuries. There seems to prevail an understanding that tissue devitalisation correlates with kinetic energy dissipated into the tissue. Other views exist too. The purpose of the study was to find out whether such a correlation can be found and at what level of confidence. METHODS: A number of reported tests done with live pigs with sufficient primary data have first been brought to the same temporally comparable level and then analysed. The tests comprise of 140 shots. To maintain consistency tests with other animals were excluded. RESULTS: The best correlation was obtained between excised muscle tissue and dissipated kinetic energy per millimetre of wound channel. An equation describing the relationship between dissipated energy E(d) and devitalised tissue m(deb) is presented as a regression function m(deb)=44.575xE(d)+10.319 with R2=0.293. An experimental method for estimating the energy used for bullet deformation of controlled deformation bullets is also presented. CONCLUSIONS: A method for using the regression function for obtaining tissue destruction figures for any point of wound channel formed in tissue simulant is presented. The figures are intended for meaningful comparison of the injury potential of various bullets and not for forecasting actual tissue injuries. The documentation of the ballistic properties in animal tests also seems somewhat lacking. Some changes in documenting firearms injuries are proposed in order to validate the methods and further enhance the fidelity of simulant testing.

Animals↗