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991.
Javier Mar Arantzazu Arrospide José María Begiristain Isabel Larrañaga Elena Elosegui Juan Oliva-Moreno 《BMC neurology》2011,11(1):46
Background
Patients with acquired brain damage (ABD) have suffered a brain lesion that interrupts vital development in the physical, psychological and social spheres. Stroke and traumatic brain injury (TBI) are the two main causes. The objectives of this study were to estimate the incidence and prevalence of ABD in the population of the Basque Country and Navarre in 2008, to calculate the associated cost of the care required and finally to assess the loss in health-related quality of life. 相似文献992.
Signal processing of heart signals for the quantification of non-deterministic events 总被引:1,自引:0,他引:1
Background
Heart signals represent an important way to evaluate cardiovascular function and often what is desired is to quantify the level of some signal of interest against the louder backdrop of the beating of the heart itself. An example of this type of application is the quantification of cavitation in mechanical heart valve patients. 相似文献993.
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996.
Eira Bermúdez-Cuamatzin Alejandro A. Ríos-Chelén Diego Gil Constantino Macías Garcia 《Biology letters》2011,7(1):36-38
Research has shown that bird songs are modified in different ways to deal with urban noise and promote signal transmission through noisy environments. Urban noise is composed of low frequencies, thus the observation that songs have a higher minimum frequency in noisy places suggests this is a way of avoiding noise masking. Most studies are correlative and there is as yet little experimental evidence that this is a short-term mechanism owing to individual plasticity. Here we experimentally test if house finches (Carpodacus mexicanus) can modulate the minimum frequency of their songs in response to different noise levels. We exposed singing males to three continuous treatments: low–high–low noise levels. We found a significant increase in minimum frequency from low to high and a decrement from high to low treatments. We also found that this was mostly achieved by modifying the frequency of the same low-frequency syllable types used in the different treatments. When different low-frequency syllables were used, those sung during the noisy condition were longer than the ones sang during the quiet condition. We conclude that house finches modify their songs in several ways in response to urban noise, thus providing evidence of a short-term acoustic adaptation. 相似文献
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E. Assenat M. Latournerie S. Thézenas S. Gaillet C. Janiszewski N. Flori A.M. Dupuy D. Azria E. Crapez R. Garrel P. Senesse 《e》2011,6(4):e171-e177
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Improvement of physical-chemical soil quality is a key step for carrying out revegetation programs of degraded lands in Mediterranean semiarid areas. Organic residue addition may restore the quality of these areas. A field experiment was conducted in a silt-loam soil (Typic Petrocalcid) from a degraded semiarid Mediterranean area to evaluate the effect of the addition of a composted urban residue on soil aggregate stability, bulk density and chemical properties and on the establishment of Pistacia lentiscus and Retama sphaerocarpa seedlings. The composted residue was applied at a rate of 6.7 kg m(-2) before planting. The nutrient content (NPK), total organic C and water soluble C were increased and bulk density was decreased, in the rhizosphere soil of both shrub species, by the composted residue. The addition of composted residue significantly increased the soil aggregate stability by about 22% for both shrub species. The beneficial effect of the composted residue on soil quality still persisted 18 months after addition. Eighteen months after planting, the addition of composted residue to soil had increased significantly the production of shoot biomass by P. lentiscus and R. sphaerocarpa, by about 160% and 320% respectively, compared to control values. Composted residue addition to soil can be considered an effective preparation method of a degraded area for carrying out successful revegetation programs with Mediterranean shrubs under semiarid conditions. 相似文献