Signal fly, Scholastes sp. (Diptera: Platystomatidae) was observed associated with animal carcasses in Malaysia. The first observation was on a monkey carcass, which was killed by using a handgun and immediately placed in a forested area in Gombak, Selangor while the second observation was on a pig that died of natural causes and whose carcass was placed in an oil palm plantation in Tanjung Sepat, Selangor. Both animal carcasses were visited by Scholastes sp. flies during the fresh decomposition period. However, the role Scholastes flies in the decomposition process remains unknown. In this paper, we report the occurrence of Scholastes sp. on animal carcasses in Malaysia for the first time.
Short tandem repeat (STR) typing continues to be the primary workhorse in forensic DNA profiling. Therefore, the present review discusses the prominent role of STR marker in criminal justice system. All over the world, deoxyribonucleic acid (DNA) profiling provides evidence that may be used to convict criminals, as an irrefutable proof of wrongful convictions, invaluable links to the actual perpetrators of crimes, and could also deter some offenders from committing more serious offences. Clearly, DNA profiling tools have also aided forensic scientists to re-evaluate old cases that were considered closed as a result of inadequate evidence. In carrying out this review, a comprehensive electronic literature search using PubMed, ScienceDirect, Google Scholar and Google Search were used, and all works meeting the subject matter were considered, including reviews, retrospective studies, observational studies and original articles. Case reports presented here, further demonstrates the crucial role of forensic DNA profiling in mitigating and providing compelling evidence for the resolution of crimes. For case report 1, there was a 100% match between the DNA recovered from the items found in the crime scene, and the suspect's DNA sample collected via buccal swab following 15 STR loci examination. Case report 2 further highlights the indispensable contribution of DNA database in solving crime. Therefore, it has become very necessary for developing countries like Nigeria to develop a national DNA database and make policies and legislatures that will further expand and enable the practice of forensic genetics, particularly DNA profiling.
Wherever an impact mark is found, either on the surface or on the recovered projectile, it is important for forensic investigators to extract useful information in solving shooting-related cases. This article reviews a collection of works on examination of impact marks upon striking of projectiles on inanimate objects, emphasizing on the retrievable information from a shooting scene and their forensic significance in shooting event reconstruction. Literature suggested that impact marks on target surfaces and the degree of deformation on striking projectiles vary according to different combinations of ammunition and surface materials. It was noted that conditions in real-case scenarios further differed unpredictably in comparison with controlled studies, where forensic investigation should be treated as case-specific basis. Furthermore, the way forensic science is researched and applied operationally has to be reconsidered to reduce the gap via translational approach for more effective use of forensic evidence.
The distributions of flies are not only confined to ground level but can also be at higher altitudes. Here, we report three forensic cases involving dipterans in high-rise buildings in Kuala Lumpur, Malaysia. Case 1 involved a corpse of adult female found at the top floor of a fifteen-story apartment. Case 2 dealt with a body of a 75-year-old female discovered in a bedroom on the eleventh floor of an eighteen-story building, while Case 3 was a 52-year-old male found in his fifth floor shop house. Interestingly, entomological analysis revealed that all corpses were infested with similar Dipterans: Megaselia scalaris (Loew) (Diptera: Phoridae), Synthesiomyia nudiseta (Wulp) (Diptera: Muscidae) and sarcophagid (Diptera: Sarcophagidae). The first two species were commonly associated with corpses found indoors at ground level. We noted the additional occurrence of blowflies Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) and Chrysomya rufifacies Macquart (Diptera: Calliphoridae) larvae in Case 2 and Case 3, respectively. Findings from this study are significant as they demonstrate that certain groups of fly can locate dead bodies even in high-rise buildings. Forensic entomofauna research on corpses found at high elevation is scarce and our study has highlighted the peculiarity of the fly species involved in Malaysia.
Tropical bed bugs, Cimex hemipterus, which commonly feeds on human blood, may be useful in forensic applications. However, unlike the common bed bug, Cimex lectularius, there is no information regarding tropical bed bug, C. hemipterus, being studied for its applications in forensics. Thus, in this study, lab-reared post-feeding tropical bed bugs were subjected to Short Tandem Repeat (STR) and Single Nucleotide Polymorphism (SNP) analyses to establish the usage of tropical bed bugs in forensics. Several post-feeding times (0, 5, 14, 30, and 45 days) were tested to determine when a complete human DNA profile could still be obtained after the bugs had taken the blood meal. The results showed that complete STR and SNP profiles could only be obtained from the D0 sample. The profile completeness decreased over time, and partial STR and SNP profiles could be obtained up to 45 days post-blood meal. The generated SNP profiles, complete or partial, were also viable for HIrisPlex-S phenotype prediction. In addition, field-collected bed bugs were also used to examine the viability of the tested STR markers, and the STR markers detected mixed profiles. The findings of this study established that the post-blood meal of tropical bed bugs is a suitable source of human DNA for forensic STR and SNP profiling. Human DNA recovered from bed bugs can be used to identify spatial and temporal relations of events.
In forensic entomology, breeding of fly larvae in a controlled laboratory environment using animal tissue is a common technique to obtain insect developmental time for the estimation of postmortem interval. Previous studies on growth media are mostly on the effect of different diets on fly development. However, the interaction effects between temperature and food type used have not been explored. The objective of this study was to compare the use of cow's liver agar and raw liver on the development of a forensically important fly, Megaselia scalaris (Loew). This study also determined the interaction between different temperatures and different food types on the growth of this species. A total of 100 M. scalaris eggs were transferred into each of the two media mentioned above. Liver agar was prepared by adding dried ground liver into nutrient agar, whilst raw liver was naturally prepared from the same animal source. This experiment was conducted at 27, 30 and 33 °C in an incubator in a continuously dark condition. Length and weight of larvae, puparia and adult samples were determined. Total developmental times for larvae feeding on liver agar at each temperature were approximately 7-15 h slower than those feeding on raw liver. Survival rates were almost equal in both diets but were lower at 33 °C. Mean larva length in both diets did not differ significantly at all temperatures, but larvae feeding on liver agar had lower mean weight values than those in raw liver at 30 and 33 °C. The effect of temperature was significant in female puparia weight and male adult weight whereas the effect of diet types was significant in both male and female puparia size and weight. Interaction effects of temperature and food type on M. scalaris puparium size and adult weight were significant, indicating that puparium size and adult weight depended on both food type and temperature. This experiment highlighted the use of cow's liver agar as an alternative diet to breed M. scalaris in the laboratory and the importance of considering the interaction effect between temperatures and food types when deciding the most suitable medium in fly larva rearing.
This paper investigated the class characteristics in English handwriting of the Chinese, Malays and Indians in Singapore, many of whom learned their native language as a second language. One hundred and fifty-four handwriting exemplars were collected and features such as letter designs, pen-lifts, letter spacing and embellishments were studied. A number of characteristic features peculiar to the individual racial group were identified, which confirmed the impact of their native language writing systems on English handwriting.
Larvae of the Synthesiomyia nudiseta (Wulp) were collected from a decomposed human corpse at the Department of Forensic Medicine, Penang Hospital. A colony of this species was established and the eggs were collected for rearing. The developmental times, rearing temperatures, and relative humidity were recorded twice daily from the time the eggs collected until adult emergence. An average of 5 larvae were randomly collected from the rearings twice daily, warm-water killed and preserved in Kahle's solution. The larval instar stages were determined by observing the number of posterior spiracular slits and the length of the preserved larvae were measured. When the larval life cycle was completed, the accumulated developmental times were calculated. A total of 8 replicates were carried out. The temperature of the rearing room was 28.5+/-1.5 degrees Celcius while the relative humidity was within 67-85%. The total developmental time for S. nudiseta was 322+/-19 hours (13.4+/-0.8 days).
The emergence of a novel human coronavirus, SARS-CoV-2, causing severe respiratory tract infections in humans, is affecting all countries of the world and has become a global health concern. Since the virus was first identified in December 2019, the number of deaths have been propagating exponentially, causing countries across the world, including Malaysia, to increase emergency measures to combat the virus. Due to the fact that the COVID-19 pandemic does not discriminate its victims, it is of paramount importance to construct a plan for management of the dead for all suspected or confirmed COVID-19 cases, including the unidentified deceased, as an essential portion of the humanitarian forensic action approach. This document provides an overview on ways to maximize the local collective capacity from various government agencies to manage the dead based on the prevailing regulations and legislation in the country, in preparation for possible large scale deaths from this pandemic. The National Institute of Forensic Medicine Malaysia has improvised procedures and guidelines for management of the dead within the existing regulations in order to achieve a balance between medicolegal requirements and the safety of personnel managing the bodies of the deceased with suspected or confirmed COVID-19 infection; at the site of death, during transport, during postmortem procedures, storage and preparation before and during burial or cremation as well as environmental cleaning and disinfection, involving various agencies in the country. A form of temporary controlled burial is as an option to allow the reinvestigation of a decedent to help formally identify victims of the pandemic such as undocumented migrants or refugees who were previously not identified. Due to the different legal requirements and mortality rates between countries, there is no one-size-fits-all approach to the management of the dead. Whenever possible, every opportunity and assistance must be given to families to mourn their loved ones, even in times of crisis or an outbreak, in order to sustain an appropriate level of dignity and respect.
Animal species identification is one of the important fields in forensic science. Unlike human forensics which makes use of DNA fingerprinting techniques to identify individuals of the same species - humans, animal forensic species identification is much more complicated as it involves the ability to identify and distinguish between hundreds to thousands of species when the material evidence is only a trace of animal tissue without the presence of any visual physical morphology. It is even more difficult when the specimen is an unknown and no reference material is available. Animal species identification is not only important for the prevention of wildlife crimes for the purpose of wildlife protection and conservation but it is also becoming more and more significant in food safety issues especially for the meat industry. Owing to the demand and the necessity of providing such services for regulation and enforcement in the context of environmental protection, food safety and biosafety, the Department of Chemistry (DOC)
Malaysia has initiated the use of DNA techniques employing the most widely used genetic markers as part of its scientific solution for animal species identification.
Hypopygiopsis violacea, a species of fly of forensic importance, was recovered from a corpse and described for the first time. The morphological structures of the second and third instar larvae of four specimens were examined using light microscope. Observations were focused on three main morphological characters: cephalopharyngeal skeleton, anterior and posterior spiracles. Cephalopharyngeal skeleton of second instar larva is darkly pigmented and without accessory sclerite below the mouth hook. The anterior spiracles of second and third instar larvae have 8-9 papillae each, arranged in a single row. The posterior spiracle of second instar larva has two spiracular slits with no thickening of peritreme. This differentiates it from the third instar, whereby the latter has three slits for each posterior spiracle. Cephalopharyngeal skeleton of third instar larva is heavily pigmented. An accessory sclerite is found below the hook part of third instar larva but is absent in second instar. Peritreme of the posterior spiracle of third instar larva is thick almost complete encircling a button. The intersegmental spines of the cuticular surface are dome-shaped and unicuspid. Third instar larva of this species is large with size approximately 15 mm long. These findings provide important identification features of immature stages of Hy. violacea which could be useful in forensic entomology.
In forensic entomology, larval rearing usually includes the presence of biological contaminants including scuttle flies (Diptera: Phoridae). Scuttle flies are recognized as forensically important insects and have been reported causing nuisance and contamination in laboratory environments. This paper reports for the first time the finding of multiple scuttle fly species affecting colonies of third instar larvae of the Oriental latrine blowfly, Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae), reared indoors at the Forensic Science Simulation Site, Universiti Kebangsaan Malaysia. Adult scuttle flies were discovered inside a rearing container after the emergence of adult C. megacephala., The scuttle fly species are Megaselia scalaris (Loew), M. spiracularis Schmitz and Puliciphora borinquenensis (Wheeler). Notes on the life history and biology of these species are discussed herein.
Myospila pudica pudica (Stein, 1915) (Diptera: Muscidae) was recorded for the first time in Malaysia during a forensic entomological study conducted at a forested area of Forensic Science Simulation Site, Faculty of Allied Health Sciences Universiti Kebangsaan Malaysia, Bangi, Selangor. This species can be differentiated from other species of its genus by having R1 setulose on dorsal surface and R4+5 more or less setulose dorsally and ventrally. The legs, including tarsi, are testaceous yellow and palpi blackish. Lateral and ventral surface of scutellum bare below the level of bristles and the third antennal segment is brownish yellow. Other features including the diverging of inner margin of lower squama from scutellum margin. This is also the first report on the occurence of M. pudica pudica (Stein, 1915) on animal carcass.
The estimation of the postmortem interval (PMI) is an essential information in death investigations. It is necessary to know the developmental data of the most important necrophagous insect species in every geographical area. Chrysomya megacephala (Fabricius, 1794) (Diptera: Calliphoridae) is one of the most common species associated with human body decomposition, especially in the tropics, so a precise knowledge of its life cycle is crucial. However, despite its ubiquity, developmental data in a range of tropical temperatures is scarce. For this reason, the aim of this study is to provide the developmental data of the blowfly, C. megacephala, in a range of tropical temperatures and to apply these data in forensic entomology. Four temperatures were examined (i.e., 27.0°C 29.5°C, 32.0°C and 34.5°C) and the time of developments from egg to adult were recorded. To build the growth curves, five larvae per day were measured with a digital caliper. Accumulated degree-days were calculated and the isomorphen diagram for this species was plotted. As we predicted, the results showed that the life cycle of this species was affected by the increasing temperature. The implications of these new data for determining the minimum PMI in forensic entomology were discussed.
Waterways are popular locations for the disposition of criminal evidence because the recovery of latent fingerprints from such evidence is difficult. Currently, small particle reagent is a method often used to visualize latent fingerprints containing carcinogenic and hazardous compounds. This study proposes an eco-friendly, safranin-tinted Candida rugosa lipase (triacylglycerol ester hydrolysis EC 3.1.1.3) with functionalized carbon nanotubes (CRL-MWCNTS/GA/SAF) as an alternative reagent to the small particle reagent. The CRL-MWCNTS/GA/SAF reagent was compared with the small particle reagent to visualize groomed, full fingerprints deposited on stainless steel knives which were immersed in a natural outdoor pond for 30 days. The quality of visualized fingerprints using the new reagent was similar (modified-Centre for Applied Science and Technology grade: 4; p > 0.05) to small particle reagent, even after 15 days of immersion. Despite the slight decrease in quality of visualized fingerprints using the CRL-MWCNTS/GA/SAF on the last three immersion periods, the fingerprints remained forensically identifiable (modified-Centre for Applied Science and Technology grade: 3). The possible chemical interactions that enabled successful visualization is also discussed. Thus, this novel reagent may provide a relatively greener alternative for the visualization of latent fingerprints on immersed non-porous objects.
A forensic entomological study conducted in an oil palm plantation in Tanjung Sepat, Selangor, Malaysia on 3 August 2007 revealed that a housefly, Musca domestica Linnaeus oviposited its eggs on a freshly dead pig. This finding indicated that housefly might play an important role in forensic investigation in determining post-mortem interval (PMI), although it was not yet found in human corpses or any animal carrion. This preliminary paper presented a first record of Musca domestica eggs found on animal carcass in the country.
Chemical etching, which is the most sensitive method to recover obliterated serial numbers on metal surfaces, has been practised quite successfully in forensic science laboratories all over the world. A large number of etchants suitable for particular metal surfaces based on empirical studies is available in the literature. This article reviews the sensitivity and efficacy of some popular etchants for recovering obliterated marks on medium carbon steel (0.31% C with ferrite-pearlite microstructure) used in automobile parts. The experiments involved engraving these carbon steel plates with some alphanumeric characters using a computer controlled machine "Gravograph" and erasing them to several depths below the bottom of their engraving depth. Seven metallographic reagents of which most of them were copper containing compounds were chosen for etching. The erased plates were etched with every one of these etchants using swabbing method. The results have revealed that Fry's reagent comprising cupric chloride 90 g, hydrochloric acid 120 mL and water 100mL provided the necessary contrast and was concluded to be the most sensitive. The same reagent was recommended by earlier workers for revealing strain lines in steel surfaces. Earlier, another reagent containing 5 g copper sulphate, 60 mL water, 30 mL (conc.) ammonium hydroxide, and 60 mL (conc.) hydrochloric acid was proved to be more sensitive to restore erased marks on low carbon steel (0.1% C with ferrite-pearlite structure) [M.A.M. Zaili, R. Kuppuswamy, H. Harun, Restoration of engraved marks on steel surfaces by etching technique, Forensic Sci. Int. 171 (2007) 27-32]. Thus the sensitivity of the etching reagent on steel surfaces appeared to be dependent on the content of carbon in the steel.
On December 1st, 2014, the sinking of Oryong 501 occurred in the Bering Sea off the east coast of Russia. A total of 60 crew members, including 35 Indonesians, 13 Filipinos, 11 South Koreans and 1 Russian inspector were on board out of which only seven survived. Through an international rescue operation, the dead bodies of 27 were found and the remaining 26 crew are still missing. After transferring the dead bodies to the Busan Harbor in South Korea, the operation to identify the deceased began involving DVI teams from three countries: Korea, Indonesia and the Philippines. When a deep sea fishing boat sinks, it is very difficult to obtain antemortem data of the crew who had been on board for a long time. This is especially so if the crews are multinational. Further, the accuracy of the antemortem data provided by the families may be questionable, and the provided data is often not standardized. Despite the fact that the antemortem data were received in different formats, the identification process for the bodies of the 27 crew from the Oryong sinking was quickly completed through the cooperation among the three DVI teams. This case is an excellent example of how efficiently a DVI operation can be conducted in the Asia Pacific region. Issues raised during this operation should enable even better preparation for similar events in the future.
Partial least squares-discriminant analysis (PLS-DA) is a versatile algorithm that can be used for predictive and descriptive modelling as well as for discriminative variable selection. However, versatility is both a blessing and a curse and the user needs to optimize a wealth of parameters before reaching reliable and valid outcomes. Over the past two decades, PLS-DA has demonstrated great success in modelling high-dimensional datasets for diverse purposes, e.g. product authentication in food analysis, diseases classification in medical diagnosis, and evidence analysis in forensic science. Despite that, in practice, many users have yet to grasp the essence of constructing a valid and reliable PLS-DA model. As the technology progresses, across every discipline, datasets are evolving into a more complex form, i.e. multi-class, imbalanced and colossal. Indeed, the community is welcoming a new era called big data. In this context, the aim of the article is two-fold: (a) to review, outline and describe the contemporary PLS-DA modelling practice strategies, and (b) to critically discuss the respective knowledge gaps that have emerged in response to the present big data era. This work could complement other available reviews or tutorials on PLS-DA, to provide a timely and user-friendly guide to researchers, especially those working in applied research.