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Functional Morphology in Paleobiology: Origins of the Method of 'Paradigms'.
This is the final version of the article. It first appeared from Springer via https://doi.org/10.1007/s10739-017-9478-7From the early nineteenth century, the successful use of fossils in stratigraphy oriented paleontology (and particularly the study of fossil invertebrates) towards geology. The consequent marginalising of biological objectives was countered in the twentieth century by the rise of 'Paläobiologie', first in the German cultural area and only later, as 'paleobiology', in the anglophone world. Several kinds of paleobiological research flourished internationally after the Second World War, among them the novel field of 'paleoecology'. Within this field there were attempts to apply functional morphology to the problematical cases of fossil organisms, for which functions cannot be observed directly. This article describes the origins of the kind of functional inference for fossils that I proposed in 1961 as the method of 'paradigms' (a year before Thomas Kuhn made that word more widely familiar with a quite different meaning). Here I summarize some of my 'worked exemplars', which were intended to show the paradigm method in action. These case-studies were all taken from the paleontologically important phylum of the Brachiopoda, but the method was claimed to have much wider implications for the interpretation of the fossil record in terms of adaptive evolution. This article takes the history of the paradigm method as far as the late 1960s. I hope to trace, in a sequel, its ambivalent fate during the 1970s and beyond, when for example Gould's critique of 'the adaptationist programme' and the rise of computer-based quantitative methods for the evolutionary interpretation of the fossil record led to the relative eclipse of functional morphology in paleontology
Understanding myth in consumer culture theory
This paper provides an understanding of the multidisciplinary synthesising of myth conceptualisation in consumer culture theory.Mythology is an umbrella term that has been used in a variety of forms and interpretations. This review draws from psychology, sociology, anthropology, cultural studies, literary criticism, history and political studies to examine the historical and discursive constructions of mythology. We distinguish multiple perspectives of mythology and demonstrate how exemplars of each are used in consumer research. Finally, we suggest new directions for mythology that pertain to consumer culture research
First-principles modeling of strain in perovskite ferroelectric thin films
We review the role that first-principles calculations have played in
understanding the effects of substrate-imposed misfit strain on epitaxially
grown perovskite ferroelectric films. We do so by analyzing the case of
BaTiO, complementing our previous publications on this subject with
unpublished data to help explain in detail how these calculations are done. We
also review similar studies in the literature for other perovskite
ferroelectric-film materials.Comment: 14 pages, submitted to Phase Transition
Are head injuries to cyclists an important cause of death in road travel fatalities?
Background:
Despite the well-recognised benefit for individuals and communities of increased active travel, cycling remains a minority travel mode in many high income countries. Fear of injury is often cited as a reason. Campaigns to promote cycle helmet wear are alleged to contribute to this. However, there is little information on whether head injuries to cyclists are an important cause of death in road travel fatalities, compared with other road users. //
Methods:
We examined secondary causes of death for road travel deaths in England 2007–2012, comparing travel modes and grouped causes of death (from national mortality statistics) as numbers and as rates, using distance travelled and time spent travelling by mode, age, and sex from National Travel Surveys for the same six years. //
Results:
Head injury was the main cause of death for 269 cyclists, 1324 pedestrians and 1046 drivers, accounting for 46%, 42% and 25% of road travel deaths at all ages in each mode respectively. Head injury was the commonest cause of death in cyclists, but most pedestrian and driver fatalities were from multiple injuries. Rates of fatal head injury per bnkm in males aged 17+ for cycling, walking, and driving were 11.2(95% CI 9.7–12.9), 23.4(21.8–25.0) and 0.7(0.6–0.7) respectively. Female fatality rates were 8.8(6.2–12.0), 9.6(8.7–10.7) and 0.4(0.4–0.5) per bnkm respectively. Using time as the denominator, rates were 0.16(0.14–0.19),0.10(0.10–0.11) and 0.03 (0.028–0.032) respectively in men and 0.10 (0.07–0.14), 0.04(0.037–0.045), and 0.01(0.012–0.016) respectively in women, per million hours travelled. //
Conclusion:
Answering the question ‘How important are head injuries in cyclists as a cause of road travel death?’ depends on the metric used for assessing importance. Pedestrians and drivers account for five and four times the number of fatal head injuries as cyclists. The fatal head injury rate is highest for cyclists by time travelled and for pedestrians using distance travelled
Integration and Operation of an Electrically Small Magnetic EZ Antenna With a High-Power Standing Wave Oscillator Source
© 2015 IEEE. The efficacy of the three-dimensional, rectangular magnetic EZ antenna for use with mesoband high-power microwave (HPM) sources has been demonstrated previously. It overcomes the typical bulky and massive impedance-matching components found currently in most HPM systems, making it an attractive option when space is very limited. However, its extremely compact nature presents practical challenges when dealing with extremely high-power sources due to the associated local field enhancements near the feed and the near-field resonant parasitic element. This letter presents a fully integrated, high-voltage source and radiating system that has several improvements in the antenna, source, and power system that have not before been demonstrated. The full system includes a ferroelectric generator, standing wave oscillator source, and electrically small antenna (ka = 0.37) operating at 510 MHz that can be packaged inside a 15-cm-diameter tube. This small diameter results in a quarter-wavelength-diameter ground plane, and the effects of this small ground plane on the radiation characteristics are explored. The development of a pressurized radome allows for operation at 73.6 kV, significantly higher than previous studies
Voxel-based magnetic resonance image postprocessing in epilepsy
OBJECTIVE: Although the general utility of voxel-based processing of structural magnetic resonance imaging (MRI) data for detecting occult lesions in focal epilepsy is established, many differences exist among studies, and it is unclear which processing method is preferable. The aim of this study was to compare the ability of commonly used methods to detect epileptogenic lesions in magnetic resonance MRI-positive and MRI-negative patients, and to estimate their diagnostic yield. METHODS: We identified 144 presurgical focal epilepsy patients, 15 of whom had a histopathologically proven and MRI-visible focal cortical dysplasia; 129 patients were MRI negative with a clinical hypothesis of seizure origin, 27 of whom had resections. We applied four types of voxel-based morphometry (VBM), three based on T1 images (gray matter volume, gray matter concentration, junction map [JM]) and one based on normalized fluid-attenuated inversion recovery (nFSI). Specificity was derived from analysis of 50 healthy controls. RESULTS: The four maps had different sensitivity and specificity profiles. All maps showed detection rates for focal cortical dysplasia patients (MRI positive and negative) of >30% at a strict threshold of p 60% with a liberal threshold of p < 0.0001 (uncorrected), except for gray matter volume (14% and 27% detection rate). All maps except nFSI showed poor specificity, with high rates of false-positive findings in controls. In the MRI-negative patients, absolute detection rates were lower. A concordant nFSI finding had a significant positive odds ratio of 7.33 for a favorable postsurgical outcome in the MRI-negative group. Spatial colocalization of JM and nFSI was rare, yet showed good specificity throughout the thresholds. SIGNIFICANCE: All VBM variants had specific diagnostic properties that need to be considered for an adequate interpretation of the results. Overall, structural postprocessing can be a useful tool in presurgical diagnostics, but the low specificity of some maps has to be taken into consideration
Light MSSM Higgs boson mass to three-loop accuracy
The light CP even Higgs boson mass, Mh, is calculated to three-loop accuracy
within the Minimal Supersymmetric Standard Model (MSSM). The result is
expressed in terms of DRbar parameters and implemented in the computer program
H3m. The calculation is based on the proper approximations and their
combination in various regions of the parameter space. The three-loop effects
to Mh are typically of the order of a few hundred MeV and opposite in sign to
the two-loop corrections. The remaining theory uncertainty due to higher order
perturbative corrections is estimated to be less than 1 GeV.Comment: 39 pages, 13 figures. v2: minor changes, typos fixe
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