Application of atomic absorption spectroscopy for detection of multimetal traces in low-voltage electrical marks

Application of atomic absorption spectroscopy to detect multimetal traces in injured skin is a promising tool for investigation of fatalities caused by electrocution. The present paper is aimed at testing the reliability of this method for metal traces detection in electric current marks and is focused on study of peculiarities of metal penetration into the skin exposed to a current impact. Bare aluminum wire, tin-lead coated copper multistrand wire, and zinc-plated steel rope were used to make electrical marks on pig skin. It is demonstrated that amount of copper, zinc, lead, and iron may serve as statistically reliable indicators for the type of wire, which caused the electrical mark, in spite of the background content of these metals in the skin without injury. Different penetration rates for different metals contained in the wire inflicting an electrical mark were observed.     

电烧伤皮肤金属元素的测定

本实验系用220V交流电源和直径2.0mm紫铜线为接触电极,在新鲜尸体腹部皮肤上做电烧伤实验。用原子吸收分光光度计对电烧伤皮肤中铜元素含量进行测定。结果表明电烧伤皮肤铜元素含量最高可达137.90μg/g。经10%福尔马林溶液固定40天以上的电烧伤皮肤铜元素含量有昕降低,但仍较正常皮肤含量为高。电烧伤皮肤铜元素含量以电流斑处为最高。本实验为电烧伤皮肤金属元素的定性与定量分析,检材的提取和处理,提供了一个较好的方法,有利于判定案件的性质和确定接触电极的金属种类。     

Analysis of a soldered wire burnt in a fire

Fire investigators frequently encounter electrical wires with melted ends at fire scenes, which can provide useful information on the cause and development of the fire even when the melted ends result from the fires. A bead on a melted end of a wire was found in the area of origin of a massive fire that lasted for nearly a whole day, devastating a factory. The bead appeared to be the end of a wire soldered to a terminal. X-ray analysis showed that the bead is a tin-copper alloy. Although regular tin-lead solder was used in the factory, lead was not detected. This contradictory result stood in the way of fire investigation. Therefore, an unused wire soldered with tin-lead solder was heated in an electric furnace at 500 degrees C for 3 h for further examination. X-ray analysis of this wire showed that copper can be alloyed with tin while losing lead in a long-term heat in a fire.     

Device and methods for the measurement of energy transfer in experiments involving thermal and electrical injuries of skin

This work is part of a larger investigation aiming at tracing differences between injuries caused by heat and electricity. Electrodes and heaters similar to the electrodes of an electric cattle baton are used to dissipate approximately 40 joules in 40 seconds in pig skin.Voltages in the range 40–60 volts (AC or DC) are applied via stainless steel electrodes and temperatures in the range 50–100 °C are applied via heaters made of copper wire. Heat transfer is controlled by electronically regulated heaters utilizing the temperature dependence of the heater wire itself as a thermometer.Transfer of electricity takes place from either commerical DC supply, from transformed voltage from the mains or from a sine voltage generator connected to a power amplifier. The energy transfer is in all cases measured by electronic integration of the dissipated power in time. The power supplied to the electrodes or the heaters is found by electronic multiplication of the applied voltage and current.Typical power vs. time curves are presented.     

Fatal Wounds by “Manja” to a Motorbike Rider in Motion

“Kite fights” are quite popular throughout Asia. Most kite variations, including the fighter kites of India, Pakistan, and Japan, are small, flat, roughly diamond‐shaped kites composed of paper, with a tapered bamboo spine and a balanced bow. They are flown with the help of a “Manja,” which is a thread made of cotton or nylon, and coated with fine glass powder using glue and other chemical adhesives to cut down opponent's kite string. The nylon “Manja” is particularly more dangerous, as it not only cuts down opponent's kite string but also causes bodily injuries to humans, which may be at times fatal. The pattern of injuries by Manja is underreported in literature. In the present case, the deceased had encountered fatal injuries by “Manja” while riding on his motorbike. This case discusses the pattern of injuries caused by Manja when the victims are in motion on their two‐wheelers.     

Identification of wires and the cutting tool by scanning electron microscope

The cut ends of aluminium and copper wires made by different pliers have been compared under the scanning electron microscope to correlate the two pieces of a wire and to identify the cutting tool. The mechanism of producing the cut ends has been discussed. Matching of extrusion marks and correspondence of breakages at the edges of the cut ends were observed. Correspondence between the fine striations was observed on the opposite faces. These features are put forward for assigning a cut wire to a source.The ends produced by repeatedly cutting a wire by the same portion of the edge of a pair of pliers have been compared. It was found that the striations and fracture zones were reproduced on the respective surfaces of the consecutive cut ends. To identify the cutting tool in wire theft cases, it is suggested that the trial cut ends can be made by cutting the wire with successive portions of the edge of the suspected tool and compare the surface features with that on the questioned ones.     

Fatal Electrocution by a Support Metal Wire

Abstract: Electrocution is not an uncommon cause of death. A case of fatal electrocution by a metal wire that was used as a support for the insulated television cable wire is reported. Electric current flowed through the metal wire when it touched the residential power line. Electrical injury caused because of contact with the live metal wire is described with histopathological findings. This case reports the circumstances that led to accidental fatal electrocution in an outdoor setting during the rainy season. Significance of death scene investigation to confirm the cause and manner of death in cases of fatal electrocution is highlighted. Public awareness programs to lay emphasis on electrical safety in domestic environment need to be introduced to prevent fatalities resulting from ignorance and/or negligence.     

The US financial regulatory reform, causes of financial crisis and its enlightenment on China

Deficiency of the US financial regulation has stimulated the enactment of the Dodd-Frank Wall Street Reform and Consumer Protection Act. The fundamental causes of the regulatory deficiency can be categorized as follows: excessively indebted consumption culture in a long term, permanently abolishing the regulation on financial derivatives by the US Commodity Futures Trading Commission, and the regulations before the reform not fitting for the fictitious economy. The operation of financial products is like to fly a kite. The financial product is the kite, governmental adjustment is the string, market regulation is the wind, national culture and legislature and judicature are the environment. Those coordinated elements can guarantee a healthy financial market. To construct an effective financial regulatory system in China, it is needed to make culture with Chinese characteristics, advance the coordinated development of governmental and market regulation, and promote financial legislations and related implementation.     

Heart embolization with the Kirschner wire without cardiac tamponade

The case of the heart embolization with the Kirschner wire that was used for shoulder trauma fixation, 2 years previously in a 67-year-old female, is reported. This case is unique; although embolization of foreign bodies to the heart is not a novel occurrence, heart embolization with non-broken Kirschner wire with a total length of 13.5 cm without cardiac tamponade was not described in medical literature so far.     

Copper toxicity following massive ingestion of coins

Two hundred seventy-five United States coins were discovered in the stomach of a mentally disturbed individual at autopsy. Many coins containing copper were corroded by prolonged contact with gastric juice, with subsequent absorption and deposition of copper in the liver and kidneys. The patient died from complications related to the acute toxic phase of chronic copper poisoning. A discussion of the case, foreign-body ingestion, gastric bezoars and the mechanism of copper toxicity is presented. To our knowledge, this is the first death due to copper intoxication following a massive ingestion of coins.     

The tubular "cookie cutter" bullet: a unique projectile

Recently marketed PMC (Pan Metal Corporation) Ultramag tubular hollow point ammunition is uniquely constructed with a two-part projectile composed of a tubular copper bullet and a Teflon wad. A fatal gunshot wound with this ammunition is described. A unique radiographic pattern and the results of test firing are also presented.     

An unusual case of high-voltage electrocution of a truck driver due to inadvertent contact of the truck with an overhead wire

Electrocution deaths are mostly accidental. However, reconstruction of events in unusual electrocution death is challenging. This article reports an accidental death due to electrocution in a highly unusual circumstance, in which a truck driver reversing his vehicle was electrocuted when his truck inadvertently touched an overhead high-voltage wire. The electric injury marks were present over the sole of the right foot. The scene investigation revealed that the high-voltage wire was loose and was below the level of the prescribed height. The truck was passing over an elevated area made up of dirt and stone. The interior of the cabin of the truck revealed a few non-insulated metallic areas over the floor of the truck, between the accelerator and the brake, which were attributed as the sources of entry of electricity into the body. The electric injury marks were different than those usually seen in high-voltage electrocution as there was an intermediate object (truck) involved, and the contact period between the truck and the electric wire was minimal. This fatality was attributed to the non-proper insulation of the interior of the truck, the negligent driving of the truck driver over the elevated surface, and the loose high-voltage wire without proper maintenance.     

Unusual self-electrocution simulating judicial electrocution by an adolescent

Electrocution is one of the rarest modes of suicide. In this case, one school going adolescent committed suicide by electrocution using bare electric wire. This is a rare case of suicidal death by applying live wires around the wrists, simulating the act of judicial electrocution. He positioned himself on armed chair and placed the nude wire loops from a cable around both wrists and switched on the current by plugging in to nearest socket by foot. There were linear electric contact wounds completely encircling around the both wrists. In addition to these linear electric burns all around wrists, there were electrical burns over both hands. This death highlights the need of supervision and close watch on children for self-destructing activities and behavior. This case also highlights unusual method adopted by adolescent to end his life.     

Fluorescent technique for macroscopic detection of electrical metallization

A fluorescence method for the detection of trace metals was investigated to visualize in situ latent current marks or electrical metallic traces on cloth. The main electrodes metallization (iron, copper, zinc, aluminum, nickel, chromium, and brass) can be identified by spraying a 0.2% solution of 8-hydroxyquinoline in ethanol followed by observation under shortwave UV light. Advantages and disadvantages of this technique are compared with previously described methods.     

Collection and direct amplification methods using the GlobalFiler™ kit for DNA recovered from common pipe bomb substrates

When analyzing DNA from exploded pipe bombs, quantities are often in trace amounts, making DNA typing extremely difficult. Amplifying minute amounts of DNA can cause stochastic effects resulting in partial or uninterpretable profiles. Therefore, the initial DNA collection from “touch” evidence must be optimized to maximize the amount of DNA available for analysis.This proof-of-concept study evaluated two different swab types with two direct amplification strategies to identify the most effective method for recovering DNA from common pipe bomb substrates. PVC and steel pipes, electrical tape, and copper wire spiked with epithelial cells were swabbed with cotton or microFLOQ® Direct Swabs and amplified directly or via a pre-treatment prior to STR amplification.Not only was the microFLOQ® Direct Swab protocol the quickest method with the least risk of contamination, but in combination with direct amplification, the microFLOQ® Direct Swabs also generated the most complete STR profiles.     

Compositional variation in bullet lead manufacture

The concentrations of antimony, copper, tin, arsenic, silver, bismuth, and cadmium in lead alloys produced by two smelters and one ammunition manufacturer were determined using inductively coupled plasma-atomic emission spectrometry. These element concentrations were used to measure the variations in composition of lead products that result from various processes involved in the manufacture of lead projectiles. In general, when a pot containing molten lead is used to cast a number of objects, these objects are similar, although not necessarily analytically indistinguishable in their elemental compositions. In each subsequent step in the processing of lead at the smelter and at the ammunition manufacturer, the size of an individual homogeneous melt of lead decreases as more distinct compositions are formed as a result of remelting and mixing of sources, including lead scrap. The ammunition manufacturer in this study produced at least 10 compositionally distinguishable groups of bullet wire in a 19.7-h period. The largest group could potentially be used to produce a maximum of 1.3 million compositionally indistinguishable 40 grain bullets.     

Comparison of metal ions recovered during DNA analysis of brass ammunition and effects of copper and zinc ions on DNA profiling

Analyzing DNA from brass surfaces poses unique challenges that may result from DNA damage and/or PCR inhibition. To examine the relationship between the metal ions present in brass ammunition and the success of Short Tandem Repeat (STR) profiling, six recovery methods were tested to determine the identity and quantity of metal ions co-recovered during DNA sampling. In addition, DNA and metal ion solutions were created at varying concentrations to determine the threshold at which deleterious effects occur. The results of this study show that copper and zinc are recovered in the highest concentrations from both fired and unfired ammunition, but at substantially lower levels than previously published. Furthermore, most metal ions co-recovered with DNA were removed during DNA purification and complete STR profiles were generated when the concentrations of copper and zinc ions were less than 0.1 M and 0.03 M, respectively.     

论网络著作权犯罪之“以营利为目的”

进入网络时代,行为人侵犯著作权犯罪的目的趋向多样化。在网络空间中,＂以营利为目的＂的主观构成要件严重束缚了我国《刑法》的打击范围,对未经授权作品的非法复制、再现作品的数量和速度决定了必须废止＂以营利为目的＂这一主观要件。在我国现有的《刑法》规定和犯罪构成框架下,不应拘泥于传统的营利方式,而应当根据网络营利的特有模式进行具体的认定。     

Selfish and Indoctrinated Economists?

Many people believe that economists in general are more selfish than other people and that this greater selfishness is due to economics education. This paper offers empirical evidence against this widely held belief. Using a unique data set on giving behaviour in connection with two social funds at the University of Zurich, it is shown that economics education does not make people act more selfishly. Rather, this natural experiment suggests that the particular behaviour of economists can be explained by a selection effect.JEL Classification: A13, A20, H41     

Ballistic characterization of the Remington Premier Copper Solid sabot shotgun slug

We evaluated the impact and penetration characteristics of the Remington Copper Solid sabot shotgun slug with standardized ballistic tests and used this information to predict tissue wounding patterns. This unique ammunition, first distributed in 1993, is composed of a solid copper, hollow-point slug with longitudinal slots cut into the nose. The slug is fitted into a hard plastic sabot with 8 finger-like projections and loaded into a shotgun shell with two plastic wads separating it from the underlying gunpowder charge. The ammunition was fired through a 12-gage shotgun using a rifled barrel, a smooth-bore barrel with rifled choke, and a smooth-bore barrel with a smooth modified choke into targets consisting of poster board and 10% ballistic gelatin at a variety of distances. The copper slug and plastic sabot created single 8-fingered asterisk-shaped defects in the poster board when fired at distances of less than 7 to 9 ft (approximately 2 to 3 m). All three barrel types performed similarly. At greater distances, the sabot impacted the targets separately from the slugs and created variably shaped defects that reflected base-first, nose-first, and side-first impacts. Increasing muzzle-to-target distances generally increased the impact distances between the slug and sabot. There was no predictable relationship between the sabot and slug impact points for any of the three barrel types. With each barrel tested, the wads created separate defects from the slug at distances greater than 5 ft (1.5 m). The distances between the slug and the wad impact points increased with increasing muzzle-to-target distances up to 40 ft (12 m), after which the wads generally no longer struck the targets. The slug created atypical defects at distances between 7 and 150 ft (approximately 2 to 45 m), probably due to yawing or tumbling. When the slug impacted the gelatin block in a nose-first orientation, the slotted nose portion tended to fragment and radially deposit pieces in the gelatin that were visible on radiographs. When the slug struck the gelatin target in a side-first orientation, it passed through the gelatin intact. The slug, sabot, and wads of this unique projectile separate and create independent impact points in a stereotypical manner independent of barrel type. This pattern of separation allows estimates to be made of ranges of fire. Wounds created in human tissues by this ammunition would likely have similar asterisk-shaped configurations, and nose fragments may be deposited in tissues and seen radiographically. Rectangular wounds created by the tumbling or yawing slug might be mistaken for intermediate target wounds.