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The intersection of paleontology and biomechanics can be reciprocally illuminating, helping to improve paleobiological knowledge of extinct species and furthering our understanding of the generality of biomechanical principles derived from study of extant species. However, working with data gleaned primarily from the fossil record has its challenges. Building on decades of prior research, we outline and critically discuss a complete workflow for biomechanical analysis of extinct species, using locomotor biomechanics in the Triassic theropod dinosaur Coelophysis as a case study. We progress from the digital capture of fossil bone morphology to creating rigged skeletal models, to reconstructing musculature and soft tissue volumes, to the development of computational musculoskeletal models, and finally to the execution of biomechanical simulations. Using a three-dimensional musculoskeletal model comprising 33 muscles, a static inverse simulation of the mid-stance of running shows that Coelophysis probably used more upright (extended) hindlimb postures and was likely capable of withstanding a vertical ground reaction force of magnitude more than 2.5 times body weight. We identify muscle force-generating capacity as a key source of uncertainty in the simulations, highlighting the need for more refined methods of estimating intrinsic muscle parameters such as fiber length. Our approach emphasizes the explicit application of quantitative techniques and physics-based principles, which helps maximize results robustness and reproducibility. Although we focus on one specific taxon and question, many of the techniques and philosophies explored here have much generality to them, so they can be applied in biomechanical investigation of other extinct organisms.
Throughout their 250 Myr history, archosaurian reptiles have exhibited a wide array of body sizes, shapes, and locomotor habits, especially in regard to terrestriality. These features make Archosauria a useful clade with which to study the interplay between body size, shape, and locomotor behavior, and how this interplay may have influenced locomotor evolution. Here, digital volumetric models of 80 taxa are used to explore how mass properties and body proportions relate to each other and locomotor posture in archosaurs. One-way, nonparametric, multivariate analysis of variance, based on the results of principal components analysis, shows that bipedal and quadrupedal archosaurs are largely distinguished from each other on the basis of just four anatomical parameters (p < 0.001): mass, center of mass position, and relative forelimb and hindlimb lengths. This facilitates the development of a quantitative predictive framework that can help assess gross locomotor posture in understudied or controversial taxa, such as the crocodile-line Batrachotomus (predicted quadruped) and Postosuchus (predicted biped). Compared with quadrupedal archosaurs, bipedal species tend to have relatively longer hindlimbs and a more caudally positioned whole-body center of mass, and collectively exhibit greater variance in forelimb lengths. These patterns are interpreted to reflect differing biomechanical constraints acting on the archosaurian Bauplan in bipedal versus quadrupedal groups, which may have shaped the evolutionary histories of their respective members.
The purpose of this study was to assess the associations of comorbid opioid use disorders and psychiatric disorders with suicide attempts among veterans seeking pain care.
The cohort (N = 226 444) was selected by identifying pain care initiation from 2012 to 2014 using national Veterans Health Administration (VHA) data. Data on opioid use disorders (OUD), psychiatric disorders, medical comorbidity, demographics at baseline, and suicide attempts in the year following the initiation of pain care were extracted from VHA databases. Relative excess risk due to interaction (RERI) was used to assess departure from additivity of effects.
Adjusted models indicated that both comorbid OUD and depression (RERI = 1.07) and comorbid OUD and AUD (RERI = 1.23) were significantly associated with additive risk of suicide attempt. In adjusted multiplicative interaction models, only comorbid OUD and bipolar disorder was significantly associated with suicide attempts; however, this association was protective (HR = 0.54).
The current findings highlight the importance of addressing opioid use disorders and alcohol use disorders and depression together to mitigate the risk of suicidal behavior.
OBJECTIVES/SPECIFIC AIMS: The purpose of this study is to use the baboon as a novel animal model for breath research and to identify and characterize baboon breath metabolites that reflect cardiometabolic function to inform us in the development of a noninvasive, cost-effective, and repeatable point-of-care diagnostic breath test. METHODS/STUDY POPULATION: Blood and urine was collected from control and IUGR at the approximate age of 3.5 years. Both groups were then placed on a high fat, high sugar, high salt diet for 7 weeks, after which blood, urine, and breath were collected. The breath samples were then subjected to comprehensive, 2-dimensional gas chromatography coupled with time-of-flight mass spectrometry. Using ChromaTOF software, breath VOCs were identified with at least an 80% spectral match against the National Institute of Standards and Technology (NIST) chemical reference library. The raw data were then statistically analyzed using MetaboAnalyst. We then interrogated multiple online databases to characterize and identify the role of VOCs that were present in both control and IUGR groups. RESULTS/ANTICIPATED RESULTS: Preliminary analyses of the breath VOCs indicate differences in expression between sexes and in control Versus IUGR groups. These results indicate unique “breath signatures.” Further analysis of the breath VOCs reveals the presence of metabolites that are involved in β-oxidation and oxidative stress pathways. DISCUSSION/SIGNIFICANCE OF IMPACT: This breath study, a first of its kind, will develop the baboon as a superior animal model for breath biomarker research. Our observed unique “breath signatures” indicate changes in lipid metabolism and oxidative stress pathways, which we hypothesize are the early metabolic changes at the cellular level that are not yet reflected in clinical lab measures. Future directions include analyzing breath VOCs that did not meet 80% spectral match, validation using SPME technology and commercial standards, and initiating a human pilot study in clinically obese, at-risk children in collaboration with physicians at the Children’s Hospital of San Antonio to develop a noninvasive, cost-effective, rapid, and repeatable point-of-care diagnostic breath test.
Mammalian carnivores are rarely incorporated in paleoenvironmental reconstructions, largely because of their rarity within the fossil record. However, multivariate statistical modeling can be successfully used to quantify specific anatomical features as environmental predictors. Here we explore morphological variability of the humerus in a closely related group of predators (Felidae) to investigate the relationship between morphometric descriptors and habitat categories. We analyze linear measurements of the humerus in three different morphometric combinations (log-transformed, size-free, and ratio), and explore four distinct ways of categorizing habitat adaptations. Open, Mixed, and Closed categories are defined according to criteria based on traditional descriptions of species, distributions, and biome occupancy. Extensive exploratory work is presented using linear discriminant analyses and several fossils are included to provide paleoecological reconstructions.
We found no significant differences in the predictive power of distinct morphometric descriptors or habitat criteria, although sample splitting into small and large cat guilds greatly improves the stability of the models. Significant insights emerge for three long-canine cats: Smilodon populator, Paramachairodus orientalis, and Dinofelis sp. from Olduvai Gorge (East Africa). S. populator and P. orientalis are both predicted to have been closed-habitat adapted taxa. The false “sabertooth” Dinofelis sp. from Olduvai Gorge is predicted to be adapted to mixed habitat. The application of felid humerus ecomorphology to the carnivoran record of Olduvai Gorge shows that the older stratigraphic levels (Bed I, 1.99–1.79 Ma) included a broader range of environments than Beds II or V, where there is an abundance of cats adapted to open environments.
Zinc oxide (ZnO) nanoparticles and nanoparticles of luminescent zinc oxide (ZnO:Zn) phosphor were successfully synthesised and well characterised. A transparent polystyrene composite sheet containing ZnO:Zn nanoparticles was prepared by a solvent casting method. The sheet manifested comparable transmission to a virgin polystyrene film due to very uniform dispersion of the ZnO:Zn nanoparticles into the polystyrene. Evidence for uniform dispersion was evident in both its luminescent properties and in a SEM image. The photoluminescent characteristics of the ZnO:Zn, both as a pure powder and embedded in a polystyrene matrix, are reported. The uniformity of the photoluminescence of the composite sheet under near ultraviolet excitation is demonstrated. The luminescent ZnO:Zn nanoparticles are shown to have applications for use not only as an inhibitor of the ultraviolet degradation of polymers, but also for providing polymers with light emitting functionality.
Happiness and satisfaction with life has emerged as a renewed topic of interest among gerontological investigators. However, the conceptualization of life satisfaction and happiness in advanced later life can present challenges relative to selection of proper measurement instrumentation. This chapter addresses the conceptualization and measurement of life satisfaction and happiness in very old age in three key ways. First, the conceptualization of subjective well-being is addressed in reference to the oldest old. Second, psychometric properties pertaining to past and current use of classical (e.g., Life Satisfaction Index-A), second-generation (e.g., Satisfaction with Life Scale), and domain-specific (e.g., Retirement Satisfaction Index) measures of subjective well-being within old and very old populations is addressed. Third, future directions for the advancement of measurement of subjective well-being in old-old populations are highlighted.
In Chapter 3, Shmotkin referred to subjective well-being as a “dynamic and flexible agent of adaptation” in old-old age. Gerontologists have a long history of developing quantitative instruments to assess feelings of satisfaction and the pursuit of happiness in later life (Ferraro & Schafer, 2008). Yet reliable and valid psychometric tools to evaluate subjective well-being among exceptionally old adults can be difficult to find. As Fry and Ikels highlighted in Chapter 15, the well-being construct is conceptually sound but often too complex to operationalize. This is a possible explanation for why quantitative assessments of subjective well-being have yielded mixed results.
We have been developing noble metal nanoparticles and nanocomposites for large scale application to glass surfaces. The novel functionality of the nanocomposites is attributed to the properties of both the metal nanoparticles and host matrix. Here a single-process route to nanocomposite thin films by spray deposition technique has been investigated. Preformed gold nanoparticles have been incorporated into several different transition metal oxides (TiO2, SnO2, ZnO). The nanocomposite films showed intense coloration due to the surface plasmon resonance effects of gold nanoparticles embedded in the host matrix. The gold nanoparticles were found well embedded into the host metal oxides homogeneously. This film deposition method can easily be scaled up and is compatible with current industrial on-line processes.
Prevalence of physical comorbidity in severe mental illness is a significant public health concern, but comparative data in people with diagnoses other than schizophrenia are sparse.
To investigate the prevalence of metabolic disease and cardiovascular risk in people with severe mental illness treated with antipsychotics in the community.
Case – control study of 90 people treated with antipsychotics in the community and 92 age- and gender-matched controls. The prevalence of metabolic syndrome and 10-year cardiovascular risk were calculated.
People on antipsychotics had a significantly worse metabolic profile than controls (F=6.583, d.f. = 15,161, P<0.0001). Moreover, metabolic syndrome was more prevalent (OR=3.68, 95% CI 1.71–7.93, P=0.001), as was cardiovascular risk across a number of outcomes. These results are consistent across diagnostic groups.
People with severe mental illness treated with antipsychotics have excess metabolic dysfunction and heightened risk for cardiovascular disease.
There is controversy over the existence and nature of blind
children's limitations in symbolic play. In this study we tested 13
5- to 9-year-old congenitally blind children for the ability to symbolize
when an adult provided scaffolding for their play. The blind children were
selected on the basis that they did not have the syndrome of autism, and
they comprised two groups matched for age (MA) and verbal ability on the
Wechsler Intelligence Scale for Children who contrasted in their ability
to engage in social relations. We also tested a group of sighted children
who were MA matched with the more socially able blind children. On the
basis of an hypothesis about the social–developmental sources of
symbolic play deficits in congenitally blind children, we predicted
differences between the socially able and socially impaired groups of
blind children in the following respects: the attribution of symbolic
meanings to play materials, the ascription of individual roles to play
figures, and the anchorage of play in the scenario as presented by the
adult. The results accorded with these predictions. Whereas the more
socially able blind children showed symbolic play that was very similar to
that of sighted children, the MA- and IQ-matched socially impaired blind
children were limited in the three aspects of their play. On the other
hand, even the socially impaired children showed instances of symbolizing.
The findings suggest a way to reconcile conflicting reports of symbolic
play deficits in young blind children, and may be relevant for explaining
the association between autism and congenital blindness.This study was supported by a PhD studentship from the Mary
Kitzinger Trust to Martin Bishop. The Hayward Foundation also contributed
financial support. We thank the pupils and staff of the following schools,
who were so generous in making the study possible: Dorton House School,
Sevenoaks; West of England School, Exeter; Joseph Clarke School, London;
Linden Lodge School, Wimbledon; Temple Bank School, Bradford; St.
Vincent's School for the Blind, Liverpool; RNIB Sunshine House
School, Northwood; and Priestley Smith School, Birmingham.
A spectroscopy and isotope study has been performed on igneous sediments from Lake Hoare, a nearly isolated ecosystem in the Dry Valleys region of Antarctica. The mineralogy and chemistry of these sediments were studied in order to gain insights into the biogeochemical processes occurring in a permanently ice-covered lake and to assist in characterizing potential habitats for life in paleolakes on Mars. Obtaining visible/near-infrared, mid-infrared and Raman spectra of such sediments provides the ground truth needed for using reflectance, emittance and Raman spectroscopy for exploration of geology, and perhaps biology, on Mars. Samples measured in this study include a sediment from the ice surface, lake bottom sediment cores from oxic and anoxic zones of the lake and the magnetic fractions of two samples.
These sediments are dominated by quartz, pyroxene, plagioclase and K-feldspar, but also contain calcite, organics, clays, sulphides and iron oxides/hydroxides that resulted from chemical and biological alteration processes. Chlorophyll-like bands are observed in the spectra of the sediment-mat layers on the surface of the lake bottom, especially in the deep anoxic region. Layers of high calcite concentration in the oxic sediments and layers of high pyrite concentration in the anoxic sediments are indicators of periods of active biogeochemical processing in the lake. Micro-Raman spectra revealed the presence of ~5 μm-sized pyrite deposits on the surface of quartz grains in the anoxic sediments. C, N and S isotope trends are compared with the chemistry and spectral properties. The δ13C and δ15N trends highlight the differences in the balance of microbial processes in the anoxic sediments versus the oxic sediments. The biogenic pyrite found in the sediments from the anoxic zone is associated with depleted δ34S values, high organic C levels and chlorophyll spectral bands and could be used as a potential biomarker mineral for paleolakes on Mars.
The appearance of Oldowan sites c. 2.5 million years ago signals one of the most important adaptive shifts in human evolution. Large mammal u butchery, stone artefact manufacture and novel transport and discard behaviours led to the accumulation of the first recognized archaeological debris. Although the earliest instances of these behaviours are 2.5 million years ago, most of what we know about Oldowan palaeoecology and behaviour is derived from localities more than half a million years younger, particularly c. 1.8 million-year-old sites from Bed I Olduvai Gorge, Tanzania (Potts 1988). Sites from Kanjera South, Homa Peninsula, southwestern Kenya, yield dense concentrations of artefacts in association with the oldest (c. 2.2 million years) substantial sample of archaeological fauna known thus far from Africa. This study is the first to use a wide range of traditional and innovative techniques to investigate Oldowan hominin behaviour and site formation processes before 2 million years ago.