Prosthetic liner-socket design for children with long congenital and amputated shoulder

BACKGROUND: Traditional cosmetic prosthetic designs for a long shoulder stump in children have several disadvantages, such as a rigid uncomfortable receiving socket, the need to use a strap fastening, and the non-cosmetic product due to the disproportionate shoulder and forearm length compared with the preserved limb. AIM: This study aimed to design, manufacture, and test a prototype of the shoulder stump liner-socket. MATERIALS AND METHODS: A new liner-socket of a shoulder cosmetic prosthesis has been developed, confirmed by a Russian Federation patent for an invention, which for the first time, in the practice of domestic prosthetics, is made of two types of silicone and has been successfully used in cosmetic prosthetics for 17 children, of whom 10 previously used traditional long stump prosthesis. Satisfaction with new liner-socket prosthesis was analyzed using a psychometric scale compared with a conventional prosthesis. RESULTS: The developed design combines both the inner socket function, which allows the elbow hinge to be attached to it and the liner properties, which ensures a comfortable stay of the stump in the receiving socket due to the properties of silicone and excludes the use of traditional bandages. CONCLUSIONS: The presented medical and technical solution ensures the simplicity and reliability of fastening the cosmetic shoulder stump prosthesis, including on the long shoulder stump, without disturbing the relatively healthy limb proportions, as well as wearing comfort.

Determinants of climbing energetic costs in humans

Previous studies in primates and other animals have shown that mass specific cost of transport (J kg−1 m−1) for climbing is independent of body size across species, but little is known about within-species allometry of climbing costs or the effects of difficulty and velocity. Here, we assess the effects of velocity, route difficulty, and anatomical variation on the energetic cost of climbing within humans. Twelve experienced rock climbers climbed on an indoor wall over a range of difficulty levels and velocities, with energy expenditure measured via respirometry. We found no effect of body mass or limb proportions on mass-specific cost of transport among subjects. Mass-specific cost of transport was negatively correlated with climbing velocity. Increased route difficulty was associated with slower climbing velocities and thus higher costs, but there was no statistically significant effect of route difficulty on energy expenditure independent of velocity. Finally, human climbing costs measured in this study were similar to published values for other primates, suggesting arboreal adaptations have a negligible effect on climbing efficiency.

The patterns and modes of the evolution of disparity in Mesozoic birds

The origin of birds from non-avian theropod dinosaurs is one of the greatest transitions in evolution. Shortly after diverging from other theropods in the Late Jurassic, Mesozoic birds diversified into two major clades—the Enantiornithes and Ornithuromorpha—acquiring many features previously considered unique to the crown group along the way. Here, we present a comparative phylogenetic study of the patterns and modes of Mesozoic bird skeletal morphology and limb proportions. Our results show that the major Mesozoic avian groups are distinctive in discrete character space, but constrained in a morphospace defined by limb proportions. The Enantiornithines, despite being the most speciose group of Mesozoic birds, are much less morphologically disparate than their sister clade, the Ornithuromorpha—the clade that gave rise to living birds, showing disparity and diversity were decoupled in avian history. This relatively low disparity suggests that diversification of enantiornithines was characterized in exhausting fine morphologies, whereas ornithuromorphs continuously explored a broader array of morphologies and ecological opportunities. We suggest this clade-specific evolutionary versatility contributed to their sole survival of the end-Cretaceous mass extinction.

The population of the medieval Plyos (based on archaeological excavations of the Varvara necropolis in Plyos, modern Ivanovo Region)

Traditionally, the emergence of the Russian medieval town of Plyos is attributed to the second half of the 12th c., when a fortress was built on the Sobornaya Mountain (upper part), and a settlement emerged in the lower area on the left bank of the River Shokhonka, right-bank tributary of the Volga River. Craftsmen and fishermen quar-ters, which presumably had appeared long before the fortress, located on the other side of Shokhonka. Plyos was first mentioned in written sources in 1141. During the archaeological excavations in the Varvarinskaya street (Varvara necropolis) on the territory of modern Plyos town (Ivanovo Region), managed by the «Ivanovo Archaeo-logical Expedition» company, human skeletal remains dated to the 10th–13th c. were found. This palaeoanthro-pological material characterizes the population which inhabited the Upper Volga region (Verkhnee Povolzhye) in the Middle Ages. The aim of this study was to analyse the formation of the anthropological features of the medie-val town population and assess its physical appearance. Material and methods: 17 skulls (11 male and 6 female) were examined according to standard craniological protocol, 19 uncomplete postcranial skeletons were measured following the standard osteometric protocol with some authors modifications: we present detailed data on the postcranial skeletons and the analysis of limb proportions and robustness of the long bones. Principal Component Analysis (PCA) was used for intergroup comparison with craniological series from ten different Russian and Belo-russian towns (11th–16th c.). Major results and conclusions. Presented paleoanthropological study has revealed a number of characteristics for the male skulls, associated with elongated cranium, average-high face and sharp horizontal facial profile. The female skulls exhibit mesocrania and smoother naso-molar area profile. Morphologi-cal analysis of the postcranial skeletons has demonstrated relatively elongated forearms and shortened shins in individuals from this burial ground. Reconstructed living stature of the males appears to be above average, and for women, on the contrary, below average. The problem of the common and specific patterns in the formation of the anthropological traits of the medieval town population cannot be addressed with the available anthropological material. However, PCA of the studied craniological sample indicates that the males are morphologically related to the medieval individuals from Yaroslavl (Russia) and partly to those from Novogrudok (Belarus). Thus, medie-val men buried on the territory of Plyos were undoubtedly related to (presumable) retainers buried in the sanitary graves in Yaroslavl.

Scelidosaurus harrisonii (Dinosauria: Ornithischia) from the Early Jurassic of Dorset, England: biology and phylogenetic relationships

A layer of keratinous scutes encased the skull of Scelidosaurus. The neurocranium and the associated principal sensory systems of this dinosaur are described. The cranial musculature is reconstructed and a subsequent functional analysis suggests that jaw motion was orthal, allowing pulping of vegetation and some high-angle shearing between opposing teeth. Wishboning of the lower jaw was enabled by transverse displacement of the quadrates, and the long-axis mandibular torsion that occurred during the chewing cycle was permitted by flexibility at the dentary symphysis. Limb proportions and pectoral and pelvic musculature reconstructions suggest that Scelidosaurus was a facultative quadruped of ‘average’ locomotor ability. It retained some anatomical features indicative of a bipedal-cursorial ancestry. Hindlimb motion was oblique-to-parasagittal to accommodate the girth of the abdomen. Scelidosaurus used a combination of costal and abdominally driven aspiration. The hypothesis that respiration was an ‘evolutionary driver’ of opisthopuby in all dinosaurs is overly simplistic. A critical assessment of datasets used to analyse the systematics of ornithischians (and thyreophoran subclades) has led to a revised dataset that positions Scelidosaurus as a stem ankylosaur, rather than a stem thyreophoran. The value of phylogenetic definitions is reconsidered in the light of the new thyreophoran cladogram.

Limb proportions and positional behavior

Major changes in body shape occurred during human evolution, but questions remain about body shape in australopiths. The present study investigates the specifics of the presumed relationships between limb indices and positional behavior underlying prior work that compared proportions among extant hominids in order to make inferences about extinct hominins. We find that although both intermembral index or ratio of diaphyseal and articular proportions distinguish humans from great apes, neigher correlates well with variation in the degree of arboreality in the locomotor repertoire of extant hominids. Brachial index and a ratio of diaphyseal and articular dimensions from the fore- and hindlimb, however, do correlate with degree of arboreality, and scale slightly positively allometrically within species in all extant taxa. These two observations are taken into consideration in a more nuanced interpretation of a reanalysis of articular-diaphyseal limb proportions in an expanded sample of the Sterkfontein postcrania. This study confirms previous findings that Australopithecus africanus had larger forelimb dimensions in relation to hindlimb dimensions than modern humans and A. afarensis, similar to the patterns seen in extant apes, particularly western gorillas. However, data presented here suggest that interpreting a particular taxon as “human-like” or “ape-like” may be overly simplistic. Instead, while both A. africanus and A. afarensis were almost certainly committed bipeds that incorporated some arboreality into their locomotor repertoire, A. africanus apparently used a set of locomotor behaviors that was more distinct from that of A. afarensis than Pan troglodytes and Gorilla gorilla are from each other.

A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight

The last two decades have seen a remarkable increase in the known diversity of basal avialans and their paravian relatives. The lack of resolution in the relationships of these groups combined with attributing the behavior of specialized taxa to the base of Paraves has clouded interpretations of the origin of avialan flight. Here, we describeHesperornithoides miesslerigen. et sp. nov., a new paravian theropod from the Morrison Formation (Late Jurassic) of Wyoming, USA, represented by a single adult or subadult specimen comprising a partial, well-preserved skull and postcranial skeleton. Limb proportions firmly establishHesperornithoidesas occupying a terrestrial, non-volant lifestyle. Our phylogenetic analysis emphasizes extensive taxonomic sampling and robust character construction, recovering the new taxon most parsimoniously as a troodontid close toDaliansaurus,Xixiasaurus, andSinusonasus. Multiple alternative paravian topologies have similar degrees of support, but proposals of basal paravian archaeopterygids, avialan microraptorians, andRahonavisbeing closer to Pygostylia than archaeopterygids or unenlagiines are strongly rejected. All parsimonious results support the hypothesis that each early paravian clade was plesiomorphically flightless, raising the possibility that avian flight originated as late as the Late Jurassic or Early Cretaceous.

Description of a partial Dromiceiomimus (Dinosauria: Theropoda) skeleton with comments on the validity of the genus

Dromiceiomimus brevitertius is a North American ornithomimid diagnosed primarily by the ratio of tibia length to femur length. It has recently, and perhaps incorrectly, been considered synonymous with Ornithomimus edmontonicus, with several authors questioning the utility of limb ratios in diagnosing taxa. While isolated ornithomimosaur material is common, specimens with sufficient diagnostic material to explore the question of synonymy are comparatively rare. The putative Dromiceiomimus specimen UALVP 16182 represents one of the few specimens in which diagnostic elements are available. It is therefore an important specimen for assessing the validity of Dromiceiomimus and for examining the utility of using limb proportions to diagnose ornithomimid taxa. In this paper, UALVP 16182 is described, the tibia/femur ratio is examined in closely related ornithomimid taxa, and the ratio is found to distinguish Dromiceiomimus from Gallimimus, Ornithomimus, and Struthiomimus. A phylogenetic analysis recovered Anserimimus and Ornithomimus as sister taxa with Dromiceiomimus as an outgroup. Comparison of the manus revealed differences in the morphology of metacarpal I and the flexor tubercle of manual ungual II-3. Differences also appear in the surangular and scapula. An examination of stratigraphic positions of various specimens indicates that Dromiceiomimus is generally higher in section than Ornithomimus, although there are too few specimens to be statistically significant. This study agrees with other studies in concluding that limb proportions are roughly isometric in small theropods like ornithomimids and that the tibia/femur ratio may therefore be useful for diagnosing certain small taxa. These findings suggest that Dromiceiomimus may indeed be a valid taxon.