Dynamic pressure measurement of cartridge operated vole captive bolt devices

IntroductionVole captive bolt devices are powder actuated spring guns that are used as a pest control mean. After having triggered the explosion of the blank cartridge by touching a metal ring around the muzzle, the vole is killed by the massive propulsion of the gas jet. Improper use and recklessness while handling these devices may cause severe injuries with the hand of the operator at particular risk. Currently, there are no experimental investigations on the ballistic background of these devices.MethodsAn experimental test set-up was designed for measurement of the firing pressure and the dynamic force of the gas jet of a vole captive bolt device. Therefore, a vole captive bolt device was prepared with a pressure take-off channel and a piezoelectric transducer for measurement of the firing pressure. For measurement of the dynamic impact force of the gas jet an annular quartz force sensor was installed on a test bench. Each three simultaneous measurements of the cartridges’ firing pressure and the dynamic force of the blast wave were taken at various distances between muzzle and load washer.ResultsThe maximum gas pressure in the explosion chamber was up to 1100 bar. The shot development over time showed a typical gas pressure curve. Flow velocity of the gas jet was up to 2000 m/s. The maximum impact force of the gas jet at the target showed a strong inverse ratio to the muzzle's distance and was up to 11,500 N for the contact shot distance. Energy density of the gas jet for the close contact shot was far beyond the energy density required for skin penetration.ConclusionThe unique design features (short tube between cartridge mouth and muzzle and narrow diameter of the muzzle) of these gadgets are responsible for the high firing pressure, velocity and force of the gas jet. These findings explain the trauma mechanics of the extensive tissue damage observed in accidental shots of these devices.     

The dynamics of injuries caused by thrown, razor-sharp shurikens

In 10 tests, the linear velocity and rotation frequency of a thrown, pointed, razor-sharp shuriken were investigated using a high-speed camera. The linear velocity (5.1-9.87 m/s) and rotation frequency (0-4.46 m/s) determine the impact (0.91-3.6 nm) of this Asiatic weapon. An impact of 3.6 Nm is sufficient to cause a penetration depth of more than 3.5 cm within the regio ossis temporalis, the regio collis lateralis and the regio intercostalis. Legally, the use of this new generation of pointed, razor-sharp shurikens should be prohibited as "sports" apparatus.     

Neck injuries caused by automatic two-point seat belts: an analysis of four cases

Although seat belts significantly reduce the extent and severity of injuries sustained by motor vehicle occupants, seat belts are known to be associated with chest and abdominal trauma. Less commonly understood are severe neck injuries caused by the use of two-point automatic shoulder harnesses without concurrent use of a manual lap belt. Such injuries may include cervical spine fractures, craniocervical dislocations and rarely decapitation. Recognizing patterned injuries caused by seat belts and the ability to correlate autopsy findings with the circumstances surrounding the death will allow for correct interpretation of seat-belt related trauma. The four cases described detail fatal neck injuries as a result of improper seat belt use in which an automatic two-point shoulder harness was used without a manual lap restraint. In two of the cases, the victims were decapitated.     

Comparison of injuries caused by the pistols Tokarev, Makarov and Glock 19 at firing distances of 10, 15 and 25cm

Firings at cloth targets and at human skin from autopsy material were performed from the pistols 7.62 mm Tokarev (TT), 9 mm Makarov (PM) and 9 x 19 mm Glock 19 with common ammunition. The differences were in the soot deposit pattern, the degree of scorching of the synthetic fibres on the edges of the entrance hole and in the findings of the soot and the gunpowder particles. The results were similar on the cloth and on the skin targets. In the case of the TT and the PM, the soot deposit patterns reminded of a blossom or shafts of rays or fans, or the bullet wipe had four narrow and four wide sections regarding the number of lands and grooves. The TT left a large amount of soot and many gunpowder particles and caused the melting of the synthetic fibres on the edges of the entrance hole, producing a defect of the material 0.1-0.3 cm in diameter and defects of textile fibres around the entrance hole. In the skin the TT caused many intraepithelial tears, folds of the epidermis and recesses of the epidermis containing soot. Firings from the PM and the Glock 19 caused the melting only of the ends of individual synthetic fibres on the edges of the entrance hole. The PM left a large amount of soot and only a few gunpowder particles. The Glock 19 gave the least soot and the greatest number of gunpowder particles and also caused tears and recesses in the epidermis. Only in the case of the Glock 19, hexagonal or polygonal zones were seen in the soot deposit pattern. The differences in the soot pattern were more distinct at the firing distance of 10 cm. By increasing the distance from 10 to 15 cm, the intensity of soot diminished and began to disappear at 25cm, but remained more visible in the case of the TT. The gunpowder particles could be found in the epidermis and deeper in both layers of the dermis at all distances fired from the TT and the Glock 19. In the case of firings from the PM, at the distance 10 cm some of the gunpowder particles had penetrated into the dermis and most of them were in the upper layer of the dermis. At the firing distance of 15 and 25 cm, the gunpowder particles were only on and in the stratum corneum.     

Comparison of injuries caused by the pistols Tokarev,Makarov and Glock 19 at firing distances of 25, 50, 75 and 100 cm

Firings in the horizontal direction at cloth targets and at human skin from autopsy material were performed using the pistols 7.62 mm Tokarev (TT), 9 mm Makarov (PM) and 9 mm × 19 mm Glock 19 with common ammunition.     

Death caused by myocarditis in Wayne County, Michigan: a 9-year retrospective study

This paper reviews 72 cases of death caused by myocarditis between the years 1996 and 2004, autopsied at the Office of the Wayne County Medical Examiner in Michigan. Myocarditis as a cause of sudden and unexpected death represented 1.3% of all natural deaths in Wayne County during said period. The year 1999 contained the highest number of deaths of this cause (18), where the average number of myocarditis deaths was 8 per year for this 9-year span. In this study, each case was reviewed based on information gathered from investigative, autopsy, and toxicology reports. Significantly, 58% of these cases were male, and 63.4% were African American. Myocarditis caused death in every age group between 7 months and 67 years, but adults between the ages of 19 and 67 were most significantly affected (75%). Flu and/or cold were the most common symptoms experienced in the days directly proceeding death (28%), followed by shortness of breath (17%) and sudden collapse (15%). Sixty-nine percent of these 72 cases were pronounced dead after ACLS (advanced cardiac life support) protocol by emergency medical services or hospital attendants. Cardiomegaly was observed in 24 cases of adults aged 19 or older (54%), and flabby/soft myocardial tissue was observed grossly in 16% of all 72 cases.     

First, do no harm: the use of covert video surveillance to detect Munchausen Syndrome by Proxy--an unethical means of "preventing" child abuse

Since it was first identified in 1977, Munchausen Syndrome by Proxy has uniquely affected the way in which the medical and legal communities deal with the issue of child abuse. Inherent in the medical response to the disease are issues of suspicion, investigation, identification, confrontation, and, of course, the health of an innocent child. Given the deceptive dynamics of this disease, however, denial and disbelief naturally overshadow every action taken by medical professionals in pursuing these issues. Fortunately, as medical knowledge about the dynamics of the disease continues to develop, medical professionals become more willing and better able to identify the disease and focus their response on the safety of the child. The greatest problem in prosecuting Munchausen Syndrome by Proxy is that judges and juries remain unwilling to accept the reality of the disease. Consequently, in an effort to confirm medical suspicions and quell legal doubts, the medical community has resorted to covert video surveillance of the abuse while it is being perpetrated in the hospital. In this Article, Flannery argues that this response is an unnecessary and unethical, means of preventing Munchausen Syndrome by Proxy and protecting the child. Flannery supports the approach taken by the Family Court of New York in addressing Munchausen Syndrome by Proxy cases. The Family Court of New York recognizes the unique dynamics of this bizarre disorder, and, therefore, considers all cumulative circumstantial evidence in a Munchausen Syndrome by Proxy case, comparing the facts of the subject case to the commonly accepted features of confirmed cases. Part of the circumstantial evidence that should be considered, Flannery argues, is the dissipation of the child's condition upon temporary separation from the alleged perpetrating parent. As is done by the Flannery Court of New York, a res ipsa loquitur standard should then be applied, and an appropriate disposition for the child should be determined. By employing this standard, the court may confirm suspicions of Munchausen Syndrome by Proxy while avoiding the unnecessary harm to the child inherent in the covert video surveillance of Munchausen Syndrome by Proxy.