The Modern Compound Bow

Bows and arrows are ancient weapons that have risen and fallen as the preeminent armaments used by man. Because of the ubiquity of firearms, fatalities from archery injuries in the United States have radically declined. However, when deaths involving this weapon do present themselves, the paucity of reference materials can be a hurdle for forensic pathologists and other forensic scientists. This article will provide a brief history of the origins of the bow and the inception of the compound bow. Comparing and contrasting the structures comprising a traditional bow to those of the modern compound bow will provide insight into how these components function in unison to propel arrows.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141095/1/jfo13503.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/141095/2/jfo13503_am.pd

Morphology of Modern Arrowhead Tips on Human Skin Analog

Archery has experienced a recent resurgence in participation and has seen increases in archery range attendance and in children and young adults seeking archery lessons. Popular literature and movies prominently feature protagonists well versed in this form of weaponry. Periodic homicide cases in the United States involving bows are reported, and despite this and the current interest in the field, there are no manuscripts published on a large series of arrow wounds. This experiment utilizes a broad selection of modern arrowheads to create wounds for comparison. While general appearances mimicked the arrowhead shape, details such as the presence of abrasions were greatly influenced by the design of the arrowhead tip. Additionally, in the absence of projectiles or available history, arrowhead injuries can mimic other instruments causing penetrating wounds. A published resource on arrowhead injuries would allow differentiation of causes of injury by forensic scientists.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141548/1/jfo13502.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/141548/2/jfo13502_am.pd

Hyperthermia, Thermal Injuries, and Death from a Forced Convection Heat Source: A Case Report and Experimental Model

Heatâ related deaths of children are most often encountered in the context of enclosed vehicles in summer months. Deviating from this, a 16â monthâ old boy was found unresponsive in a stroller that was placed adjacent to a space heater during midâ winter. The cause of death was hyperthermia and thermal injuries. Manner of death determination was difficult due to alleged surrounding circumstances. To understand the timeâ course of this child’s injuries, a child death scene investigation was performed; the stroller and space heater were recovered. In a reâ enactment of the events, a slaughtered pig approximating the child’s size was warmed using a water bath and placed in the stroller beside the space heater. Cutaneous temperature measurements showed rapid initial temperature rise with subsequent steady increases. Tanning of the skin was seen on periodic direct observations. Internal temperature monitoring illustrated steady increases. This experiment was essential in classifying the manner of death as homicide.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136740/1/jfo13307_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136740/2/jfo13307.pd

The Difficulties in Assessing Wounds Created by .410 Bore Ammunition and Weapons

When interpreting firearm injuries, the distinction between gunshot wounds and shotgun wounds is important, and separation of these categories is typically straightforward. However, .410 bore firearms can make the classification difficult. Shotguns and revolvers that can fire the same .410 bore ammunition are readily available. This study investigates the soot and gunpowder deposits and pellet patterning of these two types of weapons using cartridges specially designed for .410 bore revolvers and standard birdshot pellet ammunition. For both ammunition types, the revolver had more prompt pellet dispersion and positive detection of gunpowder at greater distances compared to the shotgun. Additionally, .410 bore slugs are of similar caliber to many common bullets. In comparing the .410 bore slugs to equivalent bullets, some morphologic differences may be imparted on the skin by the slugs, but the greatest insight into the weapon remained with the retained projectiles.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154370/1/jfo14181.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154370/2/jfo14181_am.pd

Discordance of Gross and Histologic Findings in Estimating the Range of Fire of Gunshot Wounds

Forensic pathologist use soot and/or stippling surrounding entrance gunshot wounds in categorizing range of fire. If absent, some pathologists suggest utilizing histology when the range is diagnostically critical. This study investigates the concordance of macroscopic and microscopic findings in estimating range of fire by evaluating gunshot entrance and exit wounds made through human tissue analogs at defined distances using two handgun calibers. Examination of over 150 entrance wounds verified the ease of visually detecting soot from a muzzle distance of contact to 1 foot (30.5 cm), and its absence at 9 feet (274.3 cm). Distinctly apparent was bullet wipe surrounding the entrance wounds regardless of muzzle distance. Although variations existed, dark material was histologically identified in many skin, soft tissue, and bone sections at all ranges with both calibers. These nonparallel results decrease the dependability of histology for range of fire estimation and reinforce using gross observation.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151265/1/jfo14055_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151265/2/jfo14055.pd

Twisted Bethe equations from a twisted S-matrix

All-loop asymptotic Bethe equations for a 3-parameter deformation of AdS5/CFT4 have been proposed by Beisert and Roiban. We propose a Drinfeld twist of the AdS5/CFT4 S-matrix, together with c-number diagonal twists of the boundary conditions, from which we derive these Bethe equations. Although the undeformed S-matrix factorizes into a product of two su(2|2) factors, the deformed S-matrix cannot be so factored. Diagonalization of the corresponding transfer matrix requires a generalization of the conventional algebraic Bethe ansatz approach, which we first illustrate for the simpler case of the twisted su(2) principal chiral model. We also demonstrate that the same twisted Bethe equations can alternatively be derived using instead untwisted S-matrices and boundary conditions with operatorial twists.Comment: 42 pages; v2: a new appendix on sl(2) grading, 2 additional references, and some minor changes; v3: improved Appendix D, additional references, and further minor changes, to appear in JHE

Regional expression of HOXA4 along the aorta and its potential role in human abdominal aortic aneurysms

<p>Abstract</p> <p>Background</p> <p>The infrarenal abdominal aorta exhibits increased disease susceptibility relative to other aortic regions. Allograft studies exchanging thoracic and abdominal segments showed that regional susceptibility is maintained regardless of location, suggesting substantial roles for embryological origin, tissue composition and site-specific gene expression.</p> <p>Results</p> <p>We analyzed gene expression with microarrays in baboon aortas, and found that members of the HOX gene family exhibited spatial expression differences. <it>HOXA4 </it>was chosen for further study, since it had decreased expression in the abdominal compared to the thoracic aorta. Western blot analysis from 24 human aortas demonstrated significantly higher HOXA4 protein levels in thoracic compared to abdominal tissues (<it>P </it>< 0.001). Immunohistochemical staining for HOXA4 showed nuclear and perinuclear staining in endothelial and smooth muscle cells in aorta. The <it>HOXA4 </it>transcript levels were significantly decreased in human abdominal aortic aneurysms (AAAs) compared to age-matched non-aneurysmal controls (<it>P </it>< 0.00004). Cultured human aortic endothelial and smooth muscle cells stimulated with INF-γ (an important inflammatory cytokine in AAA pathogenesis) showed decreased levels of HOXA4 protein (<it>P </it>< 0.0007).</p> <p>Conclusions</p> <p>Our results demonstrated spatial variation in expression of HOXA4 in human aortas that persisted into adulthood and that downregulation of <it>HOXA4 </it>expression was associated with AAAs, an important aortic disease of the ageing population.</p