Morphology of Saw Marks in Human Bone: Identification of Class Characteristics

Accurate interpretation of saw marks on human bone is an essential part of tool mark examination in the forensic sciences, but appears neglected in practice and in the forensic sciences literature. With a basic understanding of saws and principals of cutting action, residual saw characteristics remaining on human bone can be recognized and interpreted. Two basic areas of saw cut bones are examined. Kerf floors can be examined in false starts and break away spurs. This area of a cut potentially reveals kerf size, striae patterns, and contour differences. Kerf walls, or the cut cross section of bones, reveal striae specifics such as contour, direction of stroke, and patters of cutting action. These areas of cut bone potentially reveal observable and quantifiable characteristics that can be related to predictable saw actions. These characteristics may indicate distances between saw teeth, type and amount of tooth set, tooth and blade shape, manner in which a saw is powered, and direction of saw cut. These characteristics, utilized individually or in combination, narrow the number of possible saws that potentially create a particular cut. This narrowing of the field of saws allows the examiner to assess the class. subclass, or type of saw utilized in a cut. Ultimately, examination of human bone remains will allow anthropologist to go beyond the descriptive level of analysis to confront modified bone with an appreciation for its potential forensic value

Harris Lines as Indicators of Stress: An Analysis of Tibiae From the Crow Creek Massacre Victims

Horizontal lines of increased density in bone, or Harris lines, have intrigued scientists for over a century. While earliest Harris line research dealt with medical aspects of line formation, most recent emphasis has been anthropological in nature, utilizing Harris lines as non-specific indicators of stress. The purpose of this study is to test the usefulness of Harris lines as they are applied anthropologically. A sample of 122 adult distal tibiae x-rays are used in this study. This skeletal sample represents massacre victims from the Initial Coalescent Tradition of the Crow Creek Site in central South Dakota. Each bone was sexed by discriminant function analysis and age of line formation was estimated. Harris line frequencies reveal no sex differences. However, when age-specific frequencies are compared with sex-specific human growth curves, there is a strong similarity in curve shape. These results suggest that sex influences on line formation are probably subtle but not detectable. The similarity in frequency of line formation and growth velocity has discouraging connotations for the usefulness of Harris lines as indicators of stress

Evidence of fatal skeletal injuries on Malapa Hominins 1 and 2

Malapa is one of the richest early hominin sites in Africa and the discovery site of the hominin species, Australopithecus sediba. The holotype and paratype (Malapa Hominin 1 and 2, or MH1 and MH2, respectively) skeletons are among the most complete in the early hominin record. Dating to approximately two million years BP, MH1 and MH2 are hypothesized to have fallen into a natural pit trap. All fractures evident on MH1 and MH2 skeletons were evaluated and separated based on wet and dry bone fracture morphology/characteristics. Most observed fractures are post-depositional, but those in the right upper limb of the adult hominin strongly indicate active resistance to an impact, while those in the juvenile hominin mandible are consistent with a blow to the face. The presence of skeletal trauma independently supports the falling hypothesis and supplies the first evidence for the manner of death of an australopith in the fossil record that is not attributed to predation or natural death.The National Research Foundation of South Africa (NRF)http://www.nature.com/scientificreportsam201

Nectar palatability can selectively filter bird and insect visitors to coral tree flowers

Secondary compounds in nectar may play a decisive role in determining the spectrum of floral visitors on plants. Flowers of the African coral tree Erythrina caffra are visited mainly by generalist passerine nectarivores, such as weavers and bulbuls. As the nectar of this species tastes very bitter to humans, it was hypothesized that secondary compounds may repel sunbirds and honeybees which are common in the same habitats yet seldom consume the nectar. We conducted choice tests using fresh nectar and both sucrose and hexose (glucose/fructose) solutions of the same concentration as the nectar. Whitebellied Sunbirds (Cinnyris talatala) were repelled by nectar of both E. caffra and a related species Erythrina lysistemon, but Dark-capped Bulbuls (Pycnonotus tricolor) did not discriminate between the Erythrina nectar and control sugar solution in terms of amounts consumed. Honeybees (Apis mellifera scutellata) probed exposed droplets of E. caffra nectar and a control sugar solution at the same rate, suggesting that there is no volatile deterrent, but they immediately withdrew their proboscis far more often from the droplets of Erythrina nectar than they did from the sugar solution, suggesting that they find Erythrina nectar distasteful. These results contribute to a growing awareness that non-sugar components of nectar can play important functional roles in plant pollination systems.South African National Research Foundation (NRF)http://link.springer.com/journal/106822016-03-31hb201

Continuous and transparent multimodal authentication: reviewing the state of the art

Individuals, businesses and governments undertake an ever-growing range of activities online and via various Internet-enabled digital devices. Unfortunately, these activities, services, information and devices are the targets of cybercrimes. Verifying the user legitimacy to use/access a digital device or service has become of the utmost importance. Authentication is the frontline countermeasure of ensuring only the authorized user is granted access; however, it has historically suffered from a range of issues related to the security and usability of the approaches. They are also still mostly functioning at the point of entry and those performing sort of re-authentication executing it in an intrusive manner. Thus, it is apparent that a more innovative, convenient and secure user authentication solution is vital. This paper reviews the authentication methods along with the current use of authentication technologies, aiming at developing a current state-of-the-art and identifying the open problems to be tackled and available solutions to be adopted. It also investigates whether these authentication technologies have the capability to fill the gap between high security and user satisfaction. This is followed by a literature review of the existing research on continuous and transparent multimodal authentication. It concludes that providing users with adequate protection and convenience requires innovative robust authentication mechanisms to be utilized in a universal level. Ultimately, a potential federated biometric authentication solution is presented; however it needs to be developed and extensively evaluated, thus operating in a transparent, continuous and user-friendly manner

Interpersonal Violence Between 18Th Century Native Americans And Europeans In Ohio

During the winter of 1778-1779, a garrison of 176 individuals lived within the walls of a Revolutionary era stronghold named Ft. Laurens on the banks of the Tuscarawas River, near the present-day town of Bolivar, Ohio. At least 21 individuals were buried in the fort\u27s cemetery during its occupation, 13 of whom were supposedly killed and scalped by Native Americans while gathering firewood and foraging horses. The purpose of this study is to build on previous work by Sciulli and Gramly ([1989] Am J. Phys. Anthropol. 80:11-24) by adding a more detailed analysis of the traumatic lesions, in order to better understand what happened to the victims. Lesions were analyzed based on type, location, and dimensions, as well as their overall pattern on the skeleton. Results indicate that multiple blows to the cranium were common. Out of 12 observable crania, the order of blows could be determined in only one case. Eleven of 12 of the observable crania from ambush victims and four of the seven nonambush victims exhibited lesions consistent with scalping. Evidence of postcranial trauma was noted on four individuals: one was an ambush victim, and the other three were killed at other times. No evidence of gunshot wounds was found. © 2003 Wiley-Liss, Inc

The Rorschach butterfly, understanding bone biomechanics prior to using nomenclature in bone trauma interpretations

Blunt traumas are the most common injuries observed and reported in medical examiner settings. Two common methods to describe bending bone fractures in the anthropological literature include the application of morphology nomenclature and describing characteristic fracture morphology. A nomenclature descriptor of blunt trauma, the butterfly fracture, is commonly used to describe broken long bones. In this paper, a case study of a fractured long bone in a pedestrian vehicle accident is used to highlight the complex interplay of factors involved in bone fracture formation. The application of a butterfly fracture pattern in trauma analysis is useful in establishing the bending direction of a bone, in identifying failure modes, and is valuable in teaching. Yet, butterfly fracture characteristics need to be examined in 3-dimensions for diagnosis of modes of failure, tension, shear and compression, and even then, the bending direction of a broken bone may not provide a reliable indicator of the point of impact (POI); this is especially true when a priori knowledge of the injury is unknown. Common fracture nomenclature, such as oblique, transverse and/or comminuted, as well as eponyms, are medical descriptions of an injury which are impractical to use for interpreting a broken bone from fleshed or skeletonized remains, in establishing a POI and in evaluating total bone trauma (TBT). The examination ofcharacteristic features on the surface of a broken bone associated with the modes of failure is the best approach for establishing the bending direction of a long bone.http://www.elsevier.com/locate/forsciint2020-06-01hj2019Anatom

4-(Tris(4-methyl-1<i>H</i>-pyrazol-1-yl)methyl)aniline

4-(tris(4-methyl-1H-pyrazol-1-yl)methyl)aniline was prepared in a 63% yield utilizing a C–F activation strategy from a mixture of 4-(trifluoromethyl)aniline, 4-methylpyrazole, and KOH in dimethylsulfoxide (DMSO). The identity of the product was confirmed by nuclear magnetic resonance spectroscopy, infrared spectroscopy, mass spectrometry, and single-crystal analysis. An analysis of crystals grown from the layering method (CH2Cl2/acetone/pentane) indicated two distinct polymorphs of the title compound. Moreover, density functional theory calculations utilizing the MN15L density functional and the def2-TZVP basis set indicated that 4-(tris(4-methyl-1H-pyrazol-1-yl)methyl)aniline forms with similar energetics to the previously reported unmethylated analog