1,108 research outputs found
A metric study of three types of artificial cranial modification from north-central Peru
Artificial cranial modification (ACM) involves the alteration of cranial vault shape by cultural means, and is performed during infancy while the cranial bones remain soft and malleable. The direction of normal cranial growth is altered through the application of external forces. In this study, three types of ACM from north-central Peru (posterior flattening, bilobed and circumferential) were analysed using standard craniometric techniques. The aim was to determine the effects of these forms of ACM on craniofacial morphology, and the extent to which different types of ACM could be distinguished from one another and unmodified crania on the basis of these measurements. Significant differences between artificially modified and unmodified crania, and between different types of ACM, were demonstrated in cranial vault shape for all types. Significant differences in facial morphology were found only in the bilobed group compared with the unmodified crania. Canonical variates analysis (discriminant analysis) confirmed that major differences between modification types and unmodified crania were in measurements and angles of the cranial vault. While the results show some similarities to previous studies, they add to the variability in the patterns and extent of differences documented to date. It is suggested, based on these results and visual observations, that interpopulation variation in ACM within major modification categories may explain some of the variability in results between studies, an explanation which has previously received insufficient recognition but which remains to be tested since varied methodology between studies may also be a contributory factor. While previous studies have often sought to generalise about the effects of ACM, the examination of the differences between populations even within major ACM categories may offer new insight into cultural variation in modification techniques between populations and the nature of craniofacial development.<br/
Sexual dimorphism in diaphyseal cross-sectional shape in the Medieval Muslim population of Écija, Spain and Anglo-Saxon Great Chesterford, UK
Differences in adult male and female activity patterns may influence levels of sexual dimorphism in physical dimensions, including the cross-sectional shape of long bone diaphyses. Previous studies of archaeological populations have demonstrated significant differences in diaphyseal shape between males and females. In this study, dimorphism in external diaphyseal shape of upper and lower limb bones (reflected in indices of external diaphyseal diameters), and bilateral asymmetry in these indices, were examined in two medieval populations: Muslim Écija (Spain) and Anglo-Saxon Great Chesterford (UK). Attempts were made to relate observed patterns to documentary and other osteological evidence for differences in male and female activity patterns. While few significant differences in upper limb bone cross-sectional shape were observed in either population, significant differences in shape were found in the lower limb diaphyses at Écija at the femoral midshaft and tibial foramen and midshaft levels, and at the tibial midshaft for Great Chesterford. Comparison with published data suggests that these differences are marked for Écija, and perhaps fairly high for Great Chesterford compared with other populations with an agriculture-based economy. This is consistent with documentary and osteological evidence suggesting marked gender differences in behaviour in medieval Muslim Spain. No significant differences in bilateral asymmetry were found, but the effects of small sample size cannot be ruled out
TROUT STEAKS: CONSUMER PERCEPTIONS OF A NEW FOOD ITEM
Water quality standards and a limited water supply have dramatically restricted the expansion of the U.S. trout industry. Faced with production restrictions, producers have turned to value-added products to strengthen the economic growth of the industry. In the near future, trout steaks could surface in retail outlets as a new revenue source for the mature trout industry. A telephone survey of consumers in Chicago and Los Angeles was conducted by the University of Idaho in the spring of 1997 to determine consumer preferences for trout steaks and, ultimately, to determine the viability of this product form. Using a probit analysis, fresh trout steaks were found to be more popular than frozen trout steaks. Consumers that exhibited significantly higher preference for fresh trout steaks were Hispanic, had high school education (or less), and/or believed that trout was less expensive than other meats. Chicago respondents and individuals with an urban background tended to display a higher preference toward frozen trout steaks.Consumer/Household Economics,
Micrometeorological processes driving snow ablation in an Alpine catchment
Mountain snow covers typically become patchy over the course of a melting season. The snow pattern during melt is mainly governed by the end of winter snow depth distribution and the local energy balance. The objective of this study is to investigate micrometeorological processes driving snow ablation in an Alpine catchment. For this purpose we combine a meteorological model (ARPS) with a fully distributed energy balance model (Alpine3D). Turbulent fluxes above melting snow are further investigated by using data from eddy-correlation systems. We compare modelled snow ablation to measured ablation rates as obtained from a series of Terrestrial Laser Scanning campaigns covering a complete ablation season. The measured ablation rates indicate that the advection of sensible heat causes locally increased ablation rates at the upwind edges of the snow patches. The effect, however, appears to be active over rather short distances except for very strong wind conditions. Neglecting this effect, the model is able to capture the mean ablation rates for early ablation periods but strongly overestimates snow ablation once the fraction of snow coverage is below a critical value. While radiation dominates snow ablation early in the season, the turbulent flux contribution becomes important late in the season. Simulation results indicate that the air temperatures appear to overestimate the local air temperature above snow patches once the snow coverage is below a critical value. Measured turbulent fluxes support these findings by suggesting a stable internal boundary layer close to the snow surface causing a strong decrease of the sensible heat flux towards the snow cover. Thus, the existence of a stable internal boundary layer above a patchy snow cover exerts a dominant control on the timing and magnitude of snow ablation for patchy snow covers.<br/
Pythagorean Women Their History and Writings
Pomeroy sets the Pythagorean and Neopythagorean women vividly in their historical, ecological, and intellectual contexts, illustrated with original photographs of sites and artifacts known to these women.Cover -- Contents -- Acknowledgments -- Note on Abbreviations -- Chronology -- Introduction -- 1 Who Were the Pythagorean Women? -- 2 Wives, Mothers, Sisters, Daughters -- 3 Who Were the Neopythagorean Women Authors? -- 4 Introduction to the Prose Writings of Neopythagorean Women -- 5 The Letters and Treatises of Neopythagorean Women in the East -- 6 The Letters and Treatises of Neopythagorean Women in the West -- 7 The Neopythagorean Women as Philosophers -- Notes -- Index -- A -- B -- C -- D -- E -- F -- G -- H -- I -- J -- K -- L -- M -- N -- O -- P -- R -- S -- T -- V -- W -- X -- ZPomeroy sets the Pythagorean and Neopythagorean women vividly in their historical, ecological, and intellectual contexts, illustrated with original photographs of sites and artifacts known to these women.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
Human TUBB3 mutations perturb microtubule dynamics, kinesin interactions, and axon guidance
We report that eight heterozygous missense mutations in TUBB3, encoding the neuron-specific beta-tubulin isotype III, result in a spectrum of human nervous system disorders that we now call the TUBB3 syndromes. Each mutation causes the ocular motility disorder CFEOM3, whereas some also result in intellectual and behavioral impairments, facial paralysis, and/or later-onset axonal sensorimotor polyneuropathy. Neuroimaging reveals a spectrum of abnormalities including hypoplasia of oculomotor nerves and dysgenesis of the corpus callosum, anterior commissure, and corticospinal tracts. A knock-in disease mouse model reveals axon guidance defects without evidence of cortical cell migration abnormalities. We show that the disease-associated mutations can impair tubulin heterodimer formation in vitro, although folded mutant heterodimers can still polymerize into microtubules. Modeling each mutation in yeast tubulin demonstrates that all alter dynamic instability whereas a subset disrupts the interaction of microtubules with kinesin motors. These findings demonstrate that normal TUBB3 is required for axon guidance and maintenance in mammals.Max A. Tischfield, Hagit N. Baris, Chen Wu, Guenther Rudolph, Lionel Van Maldergem, Wei He, Wai-Man Chan, Caroline Andrews, Joseph L. Demer, Richard L. Robertson, David A. Mackey, Jonathan B. Ruddle, Thomas D. Bird, Irene Gottlob, Christina Pieh, Elias I. Traboulsi, Scott L. Pomeroy, David G. Hunter, Janet S. Soul, Anna Newlin, Louise J. Sabol, Edward J. Doherty, Clara E. de Uzca´ tegui, Nicolas de Uzca´ tegui, Mary Louise Z. Collins, Emin C. Sener, Bettina Wabbels, Heide Hellebrand, Thomas Meitinger, Teresa de Berardinis, Adriano Magli, Costantino Schiavi, Marco Pastore-Trossello, Feray Koc, Agnes M. Wong, Alex V. Levin, Michael T. Geraghty, Maria Descartes, Maree Flaherty, Robyn V. Jamieson, H.U. Møller, Ingo Meuthen, David F. Callen, Janet Kerwin, Susan Lindsay, Alfons Meindl, Mohan L. Gupta, Jr., David Pellman, and Elizabeth C. Engl
Estimating demographic parameters for capture-recapture data in the presence of multiple mark types
In mark-recapture studies, various techniques can be used to uniquely identify individual animals, such as ringing, tagging or photo-identification using natural markings. In some long-term studies more than one type of marking procedure may be implemented during the study period. In these circumstances, ignoring the different mark types can produce biased survival estimates since the assumption that the different mark types are equally catchable (homogeneous capture probability across mark types) may be incorrect.We implement an integrated approach where we simultaneously analyse data obtained using three different marking techniques, assuming that animals can be cross-classified across the different mark types. We discriminate between competing models using the AIC statistic. This technique also allows us to estimate both relative mark-loss probabilities and relative recapture efficiency rates for the different marking methods.We initially perform a simulation study to explore the different biases that can be introduced if we assume a homogeneous recapture probability over mark type, before applying the method to a real dataset. We make use of data obtained from an intensive long-term observational study of UK female grey seals (Halichoerus grypus) at a single breeding colony, where three different methods are used to identify individuals within a single study: branding, tagging and photo-identification based on seal coat pattern or pelage.Peer reviewe
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Varsity Men's Track team, 1974
Front Row- S. Silva, A. Briggs, T. Lee, R. Donle, P. Varadian, J. McKenzie, J. Webber, A. Hallquist, J. Hatch, H. Fitzgerald, J. Wnek, C. Keenan, K. Osborne, D. Nygaard; Back Row- Coach M. Norcross, C. Siegal (Mgr), M. Clorite, L. Sunderlin, J. Smith, C. Baker, D. Orenstein, K. Lutgens, E. Wiles, J. Howe, R. Pomeroy, R. Newhouse, R. Baker, D. Gibbons, P. Kane, C. Owen, T. McAloon, J. Albernaz, J. Osowski (Mgr
Spatial Variability of Shortwave Irradiance for Snowmelt in Forests
The spatial variation of melt energy can influence snow cover depletion rates and in turn be influenced by the spatial variability of shortwave irradiance to snow. The spatial variability of shortwave irradiance during melt under uniform and discontinuous evergreen canopies at a U. S. Rocky Mountains site was measured, analyzed, and then compared to observations from mountain and boreal forests in Canada. All observations used arrays of pyranometers randomly spaced under evergreen canopies of varying structure and latitude. The spatial variability of irradiance for both overcast and clear conditions declined dramatically, as the sample averaging interval increased from minutes to 1 day. At daily averaging intervals, there was little influence of cloudiness on the variability of subcanopy irradiance; instead, it was dominated by stand structure. The spatial variability of irradiance on daily intervals was higher for the discontinuous canopies, but it did not scale reliably with canopy sky view. The spatial variation in irradiance resulted in a coefficient of variation of melt energy of 0.23 for the set of U. S. and Canadian stands. This variability in melt energy smoothed the snow-covered area depletion curve in a distributed melt simulation, thereby lengthening the duration of melt by 20%. This is consistent with observed natural snow cover depletion curves and shows that variations in melt energy and snow accumulation can influence snow-covered area depletion under forest canopies.</p
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