Time of death of victims found in cold water environment

Limited data is available on the application of post-mortem temperature methods to non-standard conditions, especially in problematic real life cases in which the body of the victim is found in cold water environment. Here we present our experience on two cases with known post-mortem times. A 14-year-old girl (rectal temperature 15.5 degrees C) was found assaulted and drowned after a rainy cold night (+5 degrees C) in wet clothing (four layers) at the bottom of a shallow ditch, lying in non-flowing water. The post-mortem time turned out to be 15-16 h. Four days later, at the same time in the morning, after a cold (+/- 0 degrees C) night, a young man (rectal temperature 10.8 degrees C) was found drowned in a shallow cold drain (+4 degrees C) wearing similar clothing (four layers) and being exposed to almost similar environmental and weather conditions, except of flow (7.7 l/s or 0.3 m/s) in the drain. The post-mortem time was deduced to be 10-12 h. We tested the applicability of five practical methods to estimate time of death. Henssge's temperature-time of death nomogram method with correction factors was the most versatile and gave also most accurate results, although there is limited data on choosing of correction factors. In the first case, the right correction factor was close to 1.0 (recommended 1.1-1.2), suggesting that wet clothing acted like dry clothing in slowing down body cooling. In the second case, the right correction factor was between 0.3 and 0.5, similar to the recommended 0.35 for naked bodies in flowing water.     

Does a Draft Really Influence Postmortem Body Cooling?*

Estimation of the time of death (TOD) is a very important task of forensic pathologist, and measurement of body temperature is a method deemed to be most precise during the initial postmortem period. The study aimed at verification of the significance of airflow present in the room where a corpse is found on body cooling process and hence on determination of the TOD. The experiment was performed in pigs during which the postmortem temperature of the eye, muscles, and rectum was recorded--in still air and with generated draft in the room. The results showed that the moderate airflow present in the experimental conditions did not significantly affect the course of cooling of the investigated body sites. Despite moderate wind generated in the room, the air movement close to pigs' bodies was actually minimal. This allowed to conclude that to evaluate the TOD most precisely, one should first have reliable data on the actual velocity of air in the direct vicinity of the body rather than relying on subjective sensation of the draft and using various unnecessary corrective coefficients for TOD calculation.     

Validation of a new method of providing case-specific time-of-death estimates using cadaver temperatures

The near ubiquitous presence of numerical simulation has made case-specific calculations of body temperatures following death possible so that accurate calculations of body temperatures can provide valuable information for estimating the time of death and can aid in forensic investigations. Here, a computational approach is described that has been validated against multiple, independent, and experimental investigations. The approach only requires one subjective input parameter (the heat transfer coefficient). A simple algorithm serves as a guidepost to the selection of this parameter. The algorithm incorporates clothing and the space in which the body is housed. Heat transfer coefficients that range from h = 2 W/m²/°C for bodies that are heavily clothed to h = 9 W/m²/°C for bodies that are nude (in air). The method also requires setting of ambient temperature conditions (ambient temperature)—however, that input is often available. The paucity of inputs makes this technique remarkably easy to employ. The new method is also able to calculate cadaver cooling rates for situations where the cadaver is in a timewise or spatially changing thermal environment (diurnal temperature variations, bodies partially submerged in water, changes to weather, insolation, etc.). Results from the present calculations are compared with a large body of measurements from the literature; it was found that the predictions and measurements were in excellent agreement, regardless of the ambient temperature conditions and the nature of the clothing of the body. This new calculation approach can be used with reasonable accuracy for determining cadaver cooling and time since death.     

Factors influencing the precision of estimating the postmortem interval using the triple-exponential formulae (TEF). Part I. A study of the effect of body variables and covering of the torso on the postmortem brain, liver and rectal cooling rates in 117 forensic cases

Brain, liver, rectal and environmental temperatures were continuously monitored under controlled conditions, in 117 forensic fatalities, for up to 60 h after death. Cases were studied either naked (63%) or covered with two blankets (37%). Bodies were classified into fat and thin groups. Statistical analysis and curve-fitting of the data yielded the average triple-exponential formulae for each body site and each body group. The effects of covering of the torso and body parameters such as weight, height, surface area and 'cooling size factor' (Z) on postmortem cooling are assessed and discussed. Results show that covering of the torso has a significant influence on the rate of postmortem cooling, however, there is no good correlation between the body variables and the cooling rate.     

Algor mortis: an erroneous measurement following postmortem refrigeration

Determination of the time of death is one goal of medicolegal death investigations. Algor mortis has been used as a measure of the postmortem interval (PMI). We prospectively recorded the core temperatures of 19 adult bodies entering our morgue cooler and at 3, 6, and 9 h of refrigeration. We then compared the cooling rate with the calculated body mass index (BMI). For each individual body, the rate of cooling was fairly linear with no evidence of a plateau. There was fair to moderate correlation between the BMI and the cooling rate: cooling rate = -0.052 (BMI) + 3.52. The probability of linearity in any given case was 36%. Variables affecting this correlation included the presence and the layers of clothing and if the clothing was wet. Our data confirm that algor mortis is of very limited utility in determining the PMI in bodies that have been refrigerated.     

Using cement-containing powder glue (tile cement) to dispose of a cadaver

A 40 year-old woman was killed by fist and chop blows and buried in a forest area far away from the scene of the homicide. Before covering the body with soil the perpetrator poured 25 kg of tile cement powder over it. When the victim was retrieved 6 weeks later, the cement had hardened covering the body like a plate and encasing it like a sheath. The surface of the tile cement facing towards the body was found to contain two kinds of traces: detailed cast-like reproduction of the textile structures of the victim's clothing and wallpaper-like epidermal adhesions. By means of sequencing the mitochondrial DNA the adherent horny scales could be related to the victim.     

Cooling rates of the ear and brain in pig heads submerged in water: implications for postmortem interval estimation of cadavers found in still water

The state of the art for determining postmortem interval in submerged bodies reflects a serious lack of studies. The objectives of the present study were therefore to study cerebral and tympanic cooling in water and its relation to cooling in air, in a pig model. First of all, cerebral and tympanic cooling on a single head and on an entire body were compared and proven to be very similar in air and in water. Nine pairs of heads were then exposed to 9 temperature intervals from 0 degrees C to 20 degrees C. For every set temperature, one head was placed in water, the other in "ambient" air in a thermostatic chamber. Ear and brain temperature were simultaneously measured every 10 minutes during 8 hours. Results showed that both in air and in water, cooling curves were almost exponential, regardless of the site (ear or brain) or the environmental temperature. Cooling was always more rapid in water than in air. Cerebral and tympanic cooling always had a correlation coefficient of 0.98-0.99. Assuming that these cooling patterns are applicable to man, this research may provide a starting point for postmortem interval estimation in submerged cadavers.     

A study of the shape of the post-mortem cooling curve in 117 forensic cases

The shape of the post-mortem cooling curve is described and its theoretical aspects are summarised. The concepts of the "infinite cylinder" and the "initial temperature plateau" are explained and their practical implications are discussed. Results of the study of the shape of post-mortem cooling curves for the brain, liver and the rectum of 117 cases are given. The bodies were monitored either naked or covered with blankets. For each case, temperatures of the three body sites and the environment were monitored soon after death and up to many hours post-mortem. Empirically derived three-exponential formulae were used in this study. The cooling curves for the three body sites were found to be of compound shapes and the slopes of the curves vary throughout the monitoring period. The "initial temperature plateau" was found on average in 22% of all cooling curves with the plateau incidence being significantly highest in the rectal curves (27% of rectal curves compared with 7% of brain and liver curves, P<0.1%). The effect of body sites, body build and covering of the torso on the occurrence of the plateau is assessed and discussed.     

Experimental forensic and bioanthropological aspects of soft tissue taphonomy: 1. Factors influencing postmortem tissue desiccation rate.

Euthanized rats' carcasses were exposed in an environmental chamber to multiple variables including: (1) position, (2) enveloping clothing, and (3) soil interment in an effort to determine the individual variables' effect on postmortem rate of body and visceral organ water loss. Results indicated that body water loss was enhanced by a horizontal position versus vertical, probably because of wider spread of bacteria- and enzyme-laden abdominal fluid secondary to diaphragm digestion with consequent greater tissue digestion and liquefaction. Clothing also accelerated the desiccation rate. Desiccation was about equally as effective by soil interment as by air exposure, though simulating windy conditions by tripling the air flow rate resulted in much more rapid desiccation in the air-exposed specimen. These studies suggest that the single most important factor influencing postmortem body water loss rate is the environment at the skin surface that acts to enhance or impair water removal from the skin surface and thus influences the water concentration gradient between the skin and underlying deeper tissues.     

长期饮酒对急性中毒大鼠死后体液内MDMA再分布的影响

目的研究长期饮酒对急性中毒大鼠体液中亚甲基二氧甲基苯丙胺(MDMA)死后再分布的影响。方法 SD雄性大鼠360只,随机均分为A、B、C、D 4组;A、B组以白酒,C、D组以双蒸水为饮用液体,4周后各组按150mg/kg MDMA剂量灌胃,处死后分置于25℃、4℃条件下;以VARIAN CP-3800气相色谱仪分别检测处死时血乙醇含量和0～10d内体液样品中MDMA浓度。结果 0～10d不同条件下,大鼠血液、玻璃体液及尿液中MDMA的PMR浓度变化趋势均为先升高、后降低;各时间点A、B组和C、D组大鼠各体液样本MDMA浓度较0h均有显著性差异(P<0.05),各时间点A与C组、B与D组之间体液样本MDMA浓度有显著性差异(P<0.05);A与B组、C与D组之间体液样本MDMA浓度有显著性差异(P<0.05)。结论长期饮用乙醇会降低MDMA在体液样品中的再分布,其影响程度高低依次为血液、尿液及玻璃体液;低温也可减少体液中MDMA的再分布。     

A comparison of penetration and damage caused by different types of arrowheads on loose and tight fit clothing

Bows and arrows are used more for recreation, sport and hunting in the Western world and tend not to be as popular a weapon as firearms or knives. Yet there are still injuries and fatalities caused by these low-velocity weapons due to their availability to the public and that a licence is not required to own them. This study aimed to highlight the penetration capabilities of aluminium arrows into soft tissue and bones in the presence of clothing. Further from that, how the type and fit of clothing as well as arrowhead type contribute to penetration capacity. In this study ballistic gelatine blocks (non-clothed and loose fit or tight fit clothed) were shot using a 24 lb weight draw recurve bow and aluminium arrows accompanied by four different arrowheads (bullet, judo, blunt and broadhead).The penetration capability of aluminium arrows was examined, and the depth of penetration was found to be dependent on the type of arrowhead used as well as by the type and fit or lack thereof of the clothing covering the block. Loose fit clothing reduced penetration with half of the samples, reducing penetration capacity by percentages between 0% and 98.33%, at a range of 10 m. While the remaining half of the samples covered with tight clothing led to reductions in penetration of between 14.06% and 94.12%.The damage to the clothing and the gelatine (puncturing, cutting and tearing) was affected by the shape of the arrowhead, with the least damaged caused by the blunt arrowheads and the most by the broadhead arrows. Clothing fibres were also at times found within the projectile tract within the gelatine showing potential for subsequent infection of an individual with an arrow wound.Ribs, femur bones and spinal columns encased in some of the gelatine blocks all showed varying levels of damage, with the most and obvious damage being exhibited by the ribs and spinal column.The information gleaned from the damage to clothing, gelatine blocks and bones could potentially be useful for forensic investigators, for example, when a body has been discovered with no weapons or gunshot residue present.     

Sustained Combustion of Bodies: Some Observations*

Abstract: Previous tests have explored the fire effects and fuel characteristics of animal carcasses in intense fires of relatively short duration. Here, test fires were conducted involving intact human cadavers and torsos that included nonaccelerated, long‐duration fires involving the bedding and clothing (in the manner of typical accidental deaths). The objective was to observe the fire conditions (size, radiant heat flux, and duration), where a human body represented the major fuel package in a nonaccelerated fire. The pattern of damage to the body was documented and compared with that resulting from a furnished room fire. Two intact, unembalmed human cadavers were exposed to fires of simulated accidental origin. The bedding was ignited by an open flame, and the fires were allowed to burn unaided to self‐extinguishment. It was found that normal human bodies can support a modest‐sized fire for some 6–7 h under these conditions. The presence of a substrate material that can act as a wick for the combustion of the rendered body fat results in extensive destruction of the torso where the greatest amount of subcutaneous fat resides, with less damage to the head and limbs. A third (partial) cadaver was exposed to a recreation of a typical accidental fire in a furnished room that progressed to full room involvement. This fire of some 15 min of total duration inflected only surface‐layer damage to the torso of the victim.     

Searching for Kin Amidst Tragedy—Disaster Victim Identification Operations for US Bangla Flight 211

The nature of air disasters includes factors that exacerbate challenges in the identification process. Of the 49 deceased in the US Bangla air crash in Kathmandu, Nepal, four were intact, 11 presented with burn injuries, another 11 presented with partial charring, and 23 were completely charred. Personal belongings were useful in the identification phases for all types of victims. Fingerprints were obtainable and useful in intact victims and victims with less severe burn injuries; medical and surgical information was useful in bodies with burn injuries; finally, dental findings were useful in cases of extensive charring. Other useful methods in the process included marks of identification, physical features, and exclusion. In certain resource‐limited settings, especially in closed population disasters, where scientific identification (DNA, dental records, etc.) is not currently available, personal belongings, clothing, and physical findings analyzed by an identification team using a structured organization may be cautiously used as the primary means of identification.     

Estimation of caloric deficit in a fatal case of starvation resulting from child neglect

We report the case of a 3-year-20-day-old girl who died of starvation as a result of severe neglect. Her body weight had been 12 kg 70 days before her death, but was only 5 kg at the time of autopsy. From information supplied by her parents to police, we calculated her daily caloric intake and estimated the factors for physical activity. The daily recommended dietary allowance for the victim was calculated from 700 kcal/ day x the appropriate factor for physical activity. In the absence of enough food, body fat (7.2 kcal/g body fat) and protein (4 kcal/g protein) would have been used to compensate until death. The calculated body weight at the time of death was around 5 kg. The statements of the parents therefore appear to be true.     

曲马多依赖大鼠动物模型建立的实验研究

目的建立曲马多依赖大鼠动物模型。方法 30只大鼠平均分为3组,观察以60mg/kg曲马多灌胃给药与停药戒断过程中大鼠的身体依赖和精神依赖表现。结果曲马多依赖组大鼠在给药后15min内,对声音及触摸刺激反应性增高,奔跑、跳跃、竖尾等现象为3.9±0.4次/只,明显高于对照组的0.5±0.1次/只(P<0.05);条件性位置偏爱实验中,曲马多依赖组大鼠明显偏爱给药的白箱(P<0.05)。而戒断组在停止给药后出现烦躁不安、高度激惹、尖叫等行为4.9±0.7次/只,高于依赖组的0.6±0.2次/只(P<0.05);依赖组与戒断组大鼠体重明显下降(P<0.05)。结论以60mg/kg灌胃给药112d,大鼠对曲马多产生依赖,曲马多依赖大鼠动物模型建立成功。     

The Body a ‘Double-Edged Sword’? A Qualitative Study on Swedish Female Prisoners' Relationship toward Their Bodies

Our aim was to explore female prisoners' relationship toward their bodies by means of qualitative interviews. We interviewed 14 female prisoners aged 22–53 years. Four were convicted for violent crimes, seven for drug crimes, and three for more than one crime. All of them had been addicted to drugs and the most frequently used drug was amphetamine. To analyse the participants' relationship toward their bodies we used a thematic analysis. The main result encompasses three phenomena: worries about weight, negative emotions toward the body, and negative thoughts about the body. Analyses revealed that the female prisoners' relationship toward their bodies is a changeable process. Our analyses also showed that experience of physical and sexual abuse was a very important factor for understanding these women's relationship toward their bodies.     

The showup identification procedure: An exploration of systematic biases

Purpose. Showups are common, yet little research has investigated the biasing factors that may influence showup identifications. We investigated the effects of cross‐race conditions and clothing bias on showup identification decisions. Additionally, we explored identification decisions made in a subsequent lineup dependent on race, clothing, and showup‐target‐presence. Methods. Participants watched a mock crime and were presented with a showup in which suspect race, target‐presence, and the clothing worn by the suspect were varied. Following a delay, participants viewed a target‐present or ‐absent lineup and were asked to make a second identification decision. Results. Presentation of the suspect in the clothing worn by the perpetrator increased choosing rates in both own‐race and other‐race conditions. Despite this, differential patterns of decision response latencies indicated that eyewitnesses may use clothing information differently when making own‐race compared to other‐race identification decisions. No evidence for an own‐race bias in showup identifications was found; however, other‐race lineup identifications were less accurate than own‐race lineup identifications. Further, participants in own‐race and other‐race conditions differed in the extent to which they were affected by multiple identification procedures. Viewing an own‐race innocent suspect in a showup increased subsequent false lineup identifications, while choosing the innocent suspect from the showup was necessary to increase false lineup identifications in other‐race conditions. Conclusions. Different situational factors may affect the identification accuracy of eyewitnesses in own‐race and other‐race conditions for both showup and lineup procedures. Particular caution is advised when showups are clothing‐biased and multiple identification procedures are used.     

Image analysis as an adjunct to sodium rhodizonate test in the evaluation of gunshot residues: an experimental study

It is important to investigate the clothing, as well as the body, to determine the range of fire of entry wounds in firearm injuries. Clothing can affect the amount of gunshot residues (GSR) reaching the body and their distribution. The amount and distribution of the GSR also vary according to the distance between the firearm and the target. Sodium rhodizonate test provides valuable data when clothing is available for examination. In the absence of clothing, light microscopic examinations may add additional information regarding the range of fire. In this study, a sodium rhodizonate test was done on 80 garment samples containing the bullet entrance. The 80 calfskin samples were processed histologically and were stained using Alizarin Red S. These were also evaluated with computer-assisted image analysis. Gross residues were seen on military camouflage clothing in samples from < or = 45-cm group. White flannel undershirts under the military camouflage contained rhodizonate-positive particles only around the contact wounds. With image analysis, however, the residues could be detected also in the skin samples of the 2.5-cm- and 5-cm-range groups. We suggest that the image analysis can be combined with other techniques and it can provide valuable data in the determination of entry wounds and also in the estimation of firing distance.     

Multiple-probe thermography for estimating the postmortem interval: II. Practical versions of the Triple-Exponential Formulae (TEF) for estimating the time of death in the field

A simple, reliable, and relatively accurate method for estimating the time since death is described. It is based on the Triple-Exponential Formulae (TEF), which are devised for the first time in this study. The postmortem cooling rate of the brain, liver, and rectum in 117 forensic cases were investigated (Part I). The method can be used in the field as a computer program, reference graph, or reference chart-ruler. The program is simple and can easily be run by any user. There are six reference graphs representing the average brain, liver, and rectal cooling curves for naked and covered body groups. The ruler is designed for the rectal cooling curves for covered and naked bodies. This method requires one temperature measurement of the chosen body site and the environment. The postmortem interval is estimated as a probable value +/- a possible range of time estimates with a built-in confidence limit.