Problem of “false positive” conclusions in genetic epidemiology: Lessons from the leukemia cluster near the sellafield nuclear installation

No Abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/38505/1/1370110302_ftp.pd

A volumetric technique for fossil body mass estimation applied to Australopithecus afarensis

Fossil body mass estimation is a well established practice within the field of physical anthropology. Previous studies have relied upon traditional allometric approaches, in which the relationship between one/several skeletal dimensions and body mass in a range of modern taxa is used in a predictive capacity. The lack of relatively complete skeletons has thus far limited the potential application of alternative mass estimation techniques, such as volumetric reconstruction, to fossil hominins. Yet across vertebrate paleontology more broadly, novel volumetric approaches are resulting in predicted values for fossil body mass very different to those estimated by traditional allometry. Here we present a new digital reconstruction of Australopithecus afarensis (A.L. 288-1; ‘Lucy’) and a convex hull-based volumetric estimate of body mass. The technique relies upon identifying a predictable relationship between the ‘shrink-wrapped’ volume of the skeleton and known body mass in a range of modern taxa, and subsequent application to an articulated model of the fossil taxa of interest. Our calibration dataset comprises whole body computed tomography (CT) scans of 15 species of modern primate. The resulting predictive model is characterized by a high correlation coefficient (r2 = 0.988) and a percentage standard error of 20%, and performs well when applied to modern individuals of known body mass. Application of the convex hull technique to A. afarensis results in a relatively low body mass estimate of 20.4 kg (95% prediction interval 13.5–30.9 kg). A sensitivity analysis on the articulation of the chest region highlights the sensitivity of our approach to the reconstruction of the trunk, and the incomplete nature of the preserved ribcage may explain the low values for predicted body mass here. We suggest that the heaviest of previous estimates would require the thorax to be expanded to an unlikely extent, yet this can only be properly tested when more complete fossils are available

Metacarpal trabecular bone varies with distinct hand-positions used in hominid locomotion

Trabecular bone remodels during life in response to loading and thus should, at least in part, reflect potential variation in the magnitude, frequency and direction of joint loading across different hominid species. Here we analyse the trabecular structure across all non-pollical metacarpal distal heads (Mc2-5) in extant great apes, expanding on previous volume of interest and whole-epiphysis analyses that have largely focussed on only the first or third metacarpal. Specifically, we employ both a univariate statistical mapping and a multivariate approach to test for both inter-ray and interspecific differences in relative trabecular bone volume fraction (RBV/TV) and degree of anisotropy (DA) in Mc2-5 subchondral trabecular bone. Results demonstrate that while DA values only separate Pongo from African apes (Pan troglodytes, Pan paniscus, Gorilla gorilla), RBV/TV distribution varies with the predicted loading of the metacarpophalangeal (McP) joints during locomotor behaviours in each species. Gorilla exhibits a relatively dorsal distribution of RBV/TV consistent with habitual hyper-extension of the McP joints during knuckle-walking, whereas Pongo has a palmar distribution consistent with flexed McP joints used to grasp arboreal substrates. Both Pan species possess a disto-dorsal distribution of RBV/TV, compatible with multiple hand postures associated with a more varied locomotor regime. Further inter-ray comparisons reveal RBV/TV patterns consistent with varied knuckle-walking postures in Pan species in contrast to higher RBV/TV values toward the midline of the hand in Mc2 and Mc5 of Gorilla, consistent with habitual palm-back knuckle-walking. These patterns of trabecular bone distribution and structure reflect different behavioural signals that could be useful for determining the behaviours of fossil hominins

Social insecurity and the role of possessions : buying friends or replacing them?

Title from PDF of title page (University of Missouri--Columbia, viewed on June 11, 2014).[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] This dissertation extends the literatures on coping and social anxiety by suggesting that people cope with social threats not just by directly trying to create (and restore) social relationships, but also by indirectly coping with the psychological fallout. It suggests that they do this by seeking hedonic product benefits that can salve emotional hurt, and by seeking product benefits that affirm unrelated aspects of the self concept. Two studies with different manipulations and outcome measures show that both manipulated and chronic forms of social anxiety can give rise to any of the above coping behaviors, and shows that the pursuit of these benefits is often moderated by relevant personality variables (e.g., entity theory and values-based transformations, emotional-awareness and hedonic transformations, and materialism and extrinsic transformations). These studies largely fail to replicate past findings that self-monitoring can moderate seeking social benefits. Finally, a new study by Lee and Shrum (2012) is discovered. A reanalysis of that paper's data suggests that there may be a critical role for implicit/explicit processing in consumers' deciding whether a given coping strategy is suitable. Applying this distinction to study 2's data generates a far more close-fitting description of its data

Accumulation stake readings in western Dronning Maud Land (Antarctica) along the Neumayer-Kottas-Kohnen traverse 2002 to 2003

This data collection contains readings of accumulation stake along the approximately 800 km long traverse route Neumayer-Kottas-Kohnen, Dronning Maud Land, Antarctica. By comparing the readings of an individual stake in two different seasons the amount of surface accumulation (i.e. snow deposition) or erosion (e.g. from sublimation of wind scour) can be determined. Stake readings were conducted approximately every year starting from season 1995/1996 to 2005/2006 as part of the European Project for Ice Coring In Antarctica (EPICA). The readings were carried out by a dedicated two to three person team accompanying the traverse from Neumayer station to Kohnen station. The readings were performed by a simple measurement of the visible length of the stake above the snow surface. For tilted stakes, the vertical height above the surface as well as the length of the stake was measured. New stakes were deployed when less than about 1.5 m of the previous stake was visible or a stake was lost (e.g. from breaking off or falling over and finally get burried in snow). Consequently, at some locations more than one stake is visible for several years (e.g. when the average snow accumulation was rather low). In those cases all visible stakes were recorded at the same location of such a stake cluster and added to the table as Height_1, Height 2, Height 3). Positions were measured with a simple GPS with coarse acquisition accuracy (order of several meters to tens of meters), which is sufficiently accurate to separate different stake locations (usually 500 m apart and horizontal displacement smaller than about 150 m/a, with largest displacements on the Ekström ice shelf). In very few cases, empty lines originate from missing stakes and the required position. In very few cases, a second line with the same coordinate corresponds to the same location with a fourth stake deployed as a new stake. From Neumayer station to Kottas camp stakes were deployed at approximately a 500 m interval. As the spatial variation of accumulation on the polar plateau is smaller than in the lower foreland (in this case the Ritscherflya) the stake distances was increased to 1 km to several kilometers from Kottas camp onto the polar plateau to Kohnen station. Additional field comments made by observing personal were removed from the files. However, original field notes in notebooks are available from AWI's Archive for German Polar Research (Oerter et al., 2013). Although surface accumulation is still one of the major unknowns to determine the the total surface mass balance of the Antarctic ice sheet, especially under climate change, direct long-term observations of surface accumulation are still one of the major gaps in field observations (Eisen et al., 2008). This time series of stake readings provides the basis for calculation the change in accumulation in space and time (e.g. Rotschky et al., 2007). It is thus fundamental for a decade-long record of the spatio-temporal characteristics of surface accumulation, which can be put into context to meteorological and oceanographic changes in the region

Reconceptualizing materialism as identity goal pursuits:Functions, processes, and consequences

International audienceThis article proposes an expanded conceptualization of materialism that grounds materialism in research on the self. The article stresses the functions of materialistic goal pursuit, the processes by which these functions are developed and implemented, and their potential consequences. This functional perspective views materialistic behavior as motivated goal pursuit intended to construct and maintain self-identity, and defines materialism as the extent to which people engage in identity maintenance and construction through symbolic consumption. The article discusses the utility of this conceptualization of materialism in relation to other conceptualizations and suggests avenues for future research.<br/

Career histories and managerial performance of health care chief executive officers: An empirical study in the Italian National Health Service

Background: Organizational studies widely acknowledge the importance of the relationship between CEO\u2019s career histories and managerial performance. Although the health care management literature largely explores the role of CEOs, whether and how top managers\u2019 career histories affect their own performance remains still unknown in this industry. Purpose: The aim of this study was to investigate the career histories of health care CEOs and to explore their impact on managerial performance. Methodology: Primary data were collected from a sample of 124 CEOs leading health care organizations in the Italian National Health Service in 2008. Biographic data were accessed to gather information about relevant CEOs\u2019 demographics and their career histories. The relevance of CEOs\u2019 prior experience was considered, taking into account the prominence of health care organizations in which they passed through in their career histories. Regression analyses were employed to assess the impact of CEOs\u2019 career histories on their managerial performance. Findings: Top managers already appointed as CEOs were more likely to achieve higher levels of performance. Careers with long tenure within the National Health Service appear to increase managerial performance. Those CEOs who accumulated prior experience in a large number of health care structures and who spent time working at the most prominent hospitals were also more likely to achieve higher levels of managerial performance. Implications: In health care, a CEO\u2019s career history does impact his or her managerial performance. Specifically, patterns of career that imply higher mobility across health care organizations are important. Although interorganizational mobility is significant for CEO performance, the same does not hold for mobility across industries. These findings contribute to the current debate about the need for management renovation within health care organizations

Neandertal Introgression Sheds Light on Modern Human Endocranial Globularity.

One of the features that distinguishes modern humans from our extinct relatives and ancestors is a globular shape of the braincase [1-4]. As the endocranium closely mirrors the outer shape of the brain, these differences might reflect altered neural architecture [4, 5]. However, in the absence of fossil brain tissue, the underlying neuroanatomical changes as well as their genetic bases remain elusive. To better understand the biological foundations of modern human endocranial shape, we turn to our closest extinct relatives: the Neandertals. Interbreeding between modern humans and Neandertals has resulted in introgressed fragments of Neandertal DNA in the genomes of present-day non-Africans [6, 7]. Based on shape analyses of fossil skull endocasts, we derive a measure of endocranial globularity from structural MRI scans of thousands of modern humans and study the effects of introgressed fragments of Neandertal DNA on this phenotype. We find that Neandertal alleles on chromosomes 1 and 18 are associated with reduced endocranial globularity. These alleles influence expression of two nearby genes, UBR4 and PHLPP1, which are involved in neurogenesis and myelination, respectively. Our findings show how integration of fossil skull data with archaic genomics and neuroimaging can suggest developmental mechanisms that may contribute to the unique modern human endocranial shape