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Results 201 - 250 of 957
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Ilharreborde Brice B Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, Rochester, MN, - - 2011
Treatment of chronic low back pain due to degenerative lumbar spine conditions often involves fusion of the symptomatic level. A known risk of this procedure is accelerated adjacent level degeneration. Motion preservation devices have been designed to provide stabilization to the symptomatic motion segment while preserving some physiologic motion. The ...
Hunt Gene - - 2010
Of all of the sources of evidence for evolution by natural selection, perhaps the most problematic for Darwin was the geological record of organic change. In response to the absence of species-level transformations in the fossil record, Darwin argued that the fossil record was too incomplete, too biased, and too ...
Subramanian Sreeram - - 2010
OBJECTIVE: To compare phototherapy devices based on their physical and photo-biological characteristics viz spectral properties, maximum and mean irradiance, treatable percentage of body surface area, decay of irradiance over time and in vitro photoisomerisation of bilirubin. DESIGN: In vitro experimental study. SETTING: Ocular pharmacy laboratory at a tertiary care hospital. ...
Sanei Saeid - - 2011
Murmur is the result of various heart abnormalities. A new robust approach for separation of murmur from heart sound has been suggested in this article. Singular spectrum analysis (SSA) has been adapted to the changes in the statistical properties of the data and effectively used for detection of murmur from ...
Paggetti Giulia - - 2010
A monolexemic color-naming experiment in the Italian language was performed on a sample of 1,014 colors obtained extending the OSA-UCS color system (E-OSA). Colors were rendered on a Mitsubishi Diamond pro 2070 monitor as patches subtending 10° of visual angle in a completely dark room. The 11 universal categories proposed ...
Poupard Laurent - - 2011
Several studies have correlated the ratio of the very low frequency power spectral density of heart rate increment (%VLFI) with obstructive sleep apnoea syndrome (OSAS). However, patients with impaired heart rate variability may exhibit large variations of heart rate increment (HRI) spectral pattern and alter the screening accuracy of the ...
Ghanbari Reza Namdar - - 2011
Climate signals may affect groundwater level at different time scales in different geographical regions, and those patterns or time scales can be estimated using coherence analysis. This study shows that the synthesis effort required to search for patterns at the physical geography scale is possible, and this approach should be ...
Tellechea Javier S - - 2010
Because of apparent reproductive isolation between Northern and Southern hemisphere populations of the black drum Pogonius cromis, we tested the hypothesis that advertisement calls from a southern population would differ from known calls of North American populations. Additionally, we quantified disturbance and advertisement calls, their changes with fish size and ...
Koech Phillip K - - 2010
We studied the influence of a pyridine moiety versus a phenyl moiety when introduced in the molecular design of an ambipolar host. These pyridine-based host materials for organic light-emitting diodes (OLEDs) were synthesized in three to five steps from commercially available starting materials. The isomeric hosts have similar HOMO/LUMO energies; ...
Avilés J M - - 2011
The obligate avian brood parasitic common cuckoo Cuculus canorus comprises different strains of females that specialize on particular host species by laying eggs of a constant type that often mimics those of the host. Whether cuckoos are locally adapted for mimicking populations of the hosts on which they are specialized ...
Digiovanni Jeffrey J - - 2010
Accurate prescriptive gain results in a more accurate fit, lower return rate in hearing aids, and increased patient satisfaction. In situ threshold measurements can be used to determine required gain. The Widex Corporation uses an in situ threshold measurement strategy, called the Sensogram. Real-ear measurements determine if prescriptive gain targets ...
Odendaal Lizelle J - - 2011
We investigated intraspecific variation in echolocation calls of the Cape horseshoe bat, Rhinolophus capensis, by comparing echolocation and associated morphological parameters among individuals from three populations of this species. The populations were situated in the center and at the western and eastern limits of the distribution of R. capensis. The ...
Tuomainen Ulla - - 2011
The initial response of individuals to human-induced environmental change is often behavioural. This can improve the performance of individuals under sudden, large-scale perturbations and maintain viable populations. The response can also give additional time for genetic changes to arise and, hence, facilitate adaptation to new conditions. On the other hand, ...
Li King-Fai - - 2010
Carbon dioxide (CO(2)) is the most important anthropogenic greenhouse gas in the present-day climate. Most of the community focuses on its long-term (decadal to centennial) behaviors that are relevant to climate change, but there are relatively few discussions of its higher-frequency forms of variability, and none regarding its subseasonal distribution. ...
Valigurová Andrea - - 2011
Developmental stages of the diplozoid monogenean Eudiplozoon nipponicum, comprising oncomiracidium, diporpa, juvenile, and adult, were investigated using light and scanning electron microscopy in conjunction with confocal scanning laser microscopy in order to examine body organization and identify explicit morphological adaptations to the ectoparasitic life in each stage. The parasite exhibits ...
Sulbaek Andersen M P - - 2010
Although the increasing abundance of CO(2) in our atmosphere is the main driver of the observed climate change, it is the cumulative effect of all forcing agents that dictate the direction and magnitude of the change, and many smaller contributors are also at play. Isoflurane, desflurane, and sevoflurane are widely ...
Phillips B L - - 2010
Human activities are changing habitats and climates and causing species' ranges to shift. Range expansion brings into play a set of powerful evolutionary forces at the expanding range edge that act to increase dispersal rates. One likely consequence of these forces is accelerating rates of range advance because of evolved ...
Bradley David - - 2010
(Or Shallow Water: The changing acoustic environment and potential impact on aquatic life communication) The presumption is that marine life has inhabited shallow seas and consequently adapted to the peculiarities of that environment. Anthropogenic change is the focus of this discussion in the context of both ambient noise and propagation. ...
Jiang Tinglei - - 2010
This study describes variation patterns in the constant frequency of echolocation calls emitted at rest and when not flying ("resting frequency" RF) of the least horseshoe bat, Rhinolophus pusillus, on a broad geographical scale and in response to local climatic variables. Significant differences in RF were observed among populations throughout ...
Mellone Ugo - - 2011
Weather conditions are paramount in shaping birds' migratory routes, promoting the evolution of behavioural plasticity and allowing for adaptive decisions on when to depart or stop during migration. Here, we describe and analyze the influence of weather conditions in shaping the sea-crossing stage of the pre-breeding journey made by a ...
Shafer Aaron B A - - 2010
Glacial cycles have played a dominant role in shaping the genetic structure and distribution of biota in northwestern North America. The two major ice age refugia of Beringia and the Pacific Northwest were connected by major mountain chains and bordered by the Pacific Ocean. As a result, numerous refugial options ...
Sirkiä P M - - 2010
Fluctuating selection pressure may maintain phenotypic variation because of different types of individuals being adapted to different environmental conditions. We show that the extensive variation in the coloration of male pied flycatchers (Ficedula hypoleuca) can be maintained through differences in the reproductive success of male phenotypes under different conditions. The ...
Johnson M S - - 2011
Few continuous, long-term studies have measured the intensity and variability of natural selection within a framework of clear adaptive hypotheses. In the snail Theba pisana, the proportion of effectively unbanded shells is higher in exposed habitats than in adjacent acacia thickets, which has been explained by microclimatic selection. Comparisons across ...
Bhimji Safia - - 2010
The objective of this study was to develop a novel method to quantify rotational micromotion of modular tibial components that incorporates physiologic loading conditions, a physiologic test environment, and constraint characteristics of the articulating surface. The methodology is reviewed and data are presented on four total knee designs. Results showed ...
Geraldes Armando - - 2010
Reconstructing the history of populations is a longstanding goal of molecular ecologists. In addition to a better understanding of the past, it is hoped that this knowledge would also facilitate predictions regarding species' responses to future events such as climate change. The traditional way of doing this is through the ...
Abhishek A - - 2010
Long-term wind speed variations were investigated for three midwestern cities including Indianapolis, IN; Cincinnati, OH; and Little Rock, AR in the continental United States. These cities were chosen because their topography is relatively flat and unaffected by large mountain ranges or other topographical features, they represent important regional economic centers, ...
Mitri Sara - - 2011
Communication is an indispensable component of animal societies, yet many open questions remain regarding the factors affecting the evolution and reliability of signalling systems. A potentially important factor is the level of genetic relatedness between signallers and receivers. To quantitatively explore the role of relatedness in the evolution of reliable ...
Rusch Douglas B - - 2010
Prochlorococcus describes a diverse and abundant genus of marine photosynthetic microbes. It is primarily found in oligotrophic waters across the globe and plays a crucial role in energy and nutrient cycling in the ocean ecosystem. The abundance, global distribution, and availability of isolates make Prochlorococcus a model system for understanding ...
Luca F - - 2010
Through cultural innovation and changes in habitat and ecology, there have been a number of major dietary shifts in human evolution, including meat eating, cooking, and those associated with plant and animal domestication. The identification of signatures of adaptations to such dietary changes in the genome of extant primates (including ...
Stinchcombe John R - - 2010
Trade-offs can exist within and across environments, and constrain evolutionary trajectories. To examine the effects of competition and resource availability on trade-offs, we grew individuals of recombinant inbred lines of Impatiens capensis in a factorial combination of five densities with two light environments (full light and neutral shade) and used ...
Derryberry Elizabeth P - - 2011
In many species, individuals discriminate among sexual signals of conspecific populations in the contexts of mate choice and male-male competition. Differences in signals among populations (geographical variation) are in part the result of signal evolution within populations (temporal variation). Understanding the relative effect of temporal and geographical signal variation on ...
Maggini Ivan - - 2010
The Northern Wheatear (Oenanthe oenanthe) is a migratory bird species that shows different strategies of migration between populations, adapted to cope with different ecological barriers. This raises the question whether and to which extent these adaptations are endogenously determined. We studied seasonal patterns of body mass change and nocturnal restlessness ...
Robertson J M - - 2010
The evolution of intersexual interactions, like mate choice, during ecological speciation has received widespread attention. However, changes in intrasexual interactions, like male territoriality, during ecological divergence are largely unexamined. We conducted field experiments with adaptively diverged populations of the eastern fence lizard (Sceloporus undulatus) to determine whether territorial males behaved ...
Calais E - - 2010
The spatiotemporal behaviour of earthquakes within continental plate interiors is different from that at plate boundaries. At plate margins, tectonic motions quickly reload earthquake ruptures, making the location of recent earthquakes and the average time between them consistent with the faults' geological, palaeoseismic and seismic histories. In contrast, what determines ...
Wurster Christopher M - - 2010
Today, insular Southeast Asia is important for both its remarkably rich biodiversity and globally significant roles in atmospheric and oceanic circulation. Despite the fundamental importance of environmental history for diversity and conservation, there is little primary evidence concerning the nature of vegetation in north equatorial Southeast Asia during the Last ...
Sollai Giorgia - - 2010
The aim of the present study was to examine the presence and the possible role of abdominal olfactory sensilla in Culicoides imicola mediating the search for potential hosts and oviposition sites, by means of a morphological, electrophysiological and behavioural approach. The results reported here show that in the midge C. ...
Collins Alexandra - - 2010
Positive feedbacks have been suggested as a means for non-indigenous species to successfully invade novel environments. Frequency-dependent feedbacks refer to a species performance being dependent on its local abundance in the population; however, frequency dependence is often described as a monolithic trait of a species rather than examining the variation ...
Atkins K E - - 2010
The potential impact of climate change on biodiversity is well documented. A well developed range of statistical methods currently exists that projects the possible future habitat of a species directly from the current climate and a species distribution. However, studies incorporating ecological and evolutionary processes remain limited. Here, we focus ...
Baird Emily - - 2010
Ball rolling in dung beetles is thought to have evolved as a means to escape intense inter- and intra-specific competition at the dung pile. Accordingly, dung beetles typically roll along a straight-line path away from the pile, this being the most effective escape strategy for transporting dung to a suitable ...
Santoni Cristiane Bolzachini - - 2010
Pop-rock musicians are at risk of developing hearing loss and other symptoms related to amplified music. The aim of the present study was to assess the satisfaction provided by the use of hearing protection in pop-rock musicians. Study design: Contemporary cohort study. A study of 23 male pop-rock musicians, aged ...
Ballard Grant - - 2010
Long-distance migration enables many organisms to take advantage of lucrative breeding and feeding opportunities during summer at high latitudes and then to move to lower, more temperate latitudes for the remainder of the year. The latitudinal range of the Adélie Penguin (Pygoscelis adeliae) spans approximately 22 degrees. Penguins from northern ...
Stone Brian - - 2010
Background: Extreme heat events (EHEs) are increasing in frequency in large U.S. cities and are responsible for a greater annual number of climate-related fatalities, on average, than any other form of extreme weather. In addition, low-density, sprawling patterns of urban development have been associated with enhanced surface temperatures in urbanized ...
Putman Nathan F - - 2010
Patterns of abundance across a species's reproductive range are influenced by ecological and environmental factors that affect the survival of offspring. For marine animals whose offspring must migrate long distances, natural selection may favour reproduction in areas near ocean currents that facilitate migratory movements. Similarly, selection may act against the ...
Nicholls Robert J - - 2010
Global sea levels have risen through the 20th century. These rises will almost certainly accelerate through the 21st century and beyond because of global warming, but their magnitude remains uncertain. Key uncertainties include the possible role of the Greenland and West Antarctic ice sheets and the amplitude of regional changes ...
Harvey Thomas H P - - 2010
Early fossil sponges offer a direct window onto the evolutionary emergence of animals, but insights are limited by the paucity of characters preserved in the conventional fossil record. Here, a new preservational mode for sponge spicules is reported from the lower Cambrian Forteau Formation (Newfoundland, Canada), prompting a re-examination of ...
Cavagna Andrea - - 2010
From bird flocks to fish schools, animal groups often seem to react to environmental perturbations as if of one mind. Most studies in collective animal behavior have aimed to understand how a globally ordered state may emerge from simple behavioral rules. Less effort has been devoted to understanding the origin ...
Oates Jennifer - - 2010
Humans show great flexibility in adjusting their levels of cooperation to account for current and future circumstances. For example, levels of cooperation are higher if there is more competition at the level of the whole population than with interacting partners and when individuals are likely to gain social prestige. Humans ...
Asner Gregory P - - 2010
Drought varies spatially and temporally throughout the Amazon basin, challenging efforts to assess ecological impacts via field measurements alone. Remote sensing offers a range of regional insights into drought-mediated changes in cloud cover and rainfall, canopy physiology, and fire. Here, we summarize remote sensing studies of Amazônia which indicate that: ...
Desrochers A - - 2010
Major landscape changes caused by humans may create strong selection pressures and induce rapid evolution in natural populations. In the last 100 years, eastern North America has experienced extensive clear-cutting in boreal areas, while afforestation has occurred in most temperate areas. Based on museum specimens, I show that wings of ...
Harris Alison - - 2010
Although the right fusiform face area (FFA) is often linked to holistic processing, new data suggest this region also encodes part-based face representations. We examined this question by assessing the metric of neural similarity for faces using a continuous carryover functional MRI (fMRI) design. Using faces varying along dimensions of ...
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