25 resultados para Home range (Animal geography)
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When a mixture is confined, one of the phases can condense out. This condensate, which is otherwise metastable in the bulk, is stabilized by the presence of surfaces. In a sphere-plane geometry, routinely used in atomic force microscope and surface force apparatus, it, can form a bridge connecting the surfaces. The pressure drop in the bridge gives rise to additional long-range attractive forces between them. By minimizing the free energy of a binary mixture we obtain the force-distance curves as well as the structural phase diagram of the configuration with the bridge. Numerical results predict a discontinuous transition between the states with and without the bridge and linear force-distance curves with hysteresis. We also show that similar phenomenon can be observed in a number of different systems, e.g., liquid crystals and polymer mixtures. (C). 2004 American Institute of Physics.
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Purpose - To verify the results of a diaphragmatic breathing technique (DBT) on diaphragmatic range of motion in healthy subjects. Methods - A total of 51 healthy subjects (10 male; 41 female), mean age 20 years old and a body mass index (BMI) ranging from 15.6 to 34.9 kg/m2, were enrolled in this study. Diaphragmatic range of motion was assessed by M-mode ultrasound imaging. Measurements were made before and after the DBT implementation in a standard protocol, based on 3 seconds of inspiration starting from a maximum expiration. Differences between assessments were analyzed by descriptive statistics and t-test (p < 0.05). Results - Mean value range of motion before DBT was 55.3 ± 13.4 mm and after DBT was 63.8 ± 13.2 mm showing a significant improvement of 8.5 ± 14.7 mm (p < 0.001). A strong correlation between the slope and the range of motion was found (r = 0.71, p < 0.001). Conclusions - Based on ultrasound measurements, it has been proved that DBT really contributes to a higher diaphragmatic range of motion. Future studies are needed in order to understand the influence of protocol parameters (e.g. inspiration time). Clinical implications - In the contest of evidence-based practice in physiotherapy, it has been showed by objective measurements that DBT improves the diaphragm range of motion, translating into a more efficient ventilatory function and thus can be used in clinical setting. To our knowledge this is the first study to assess the effects of DBT on range of motion of diaphragm muscle with ultrasound imaging.
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This chapter discusses the role of television within Portuguese family life. In particular, it examines how the domestication of television within the home is influenced by the social context in which different types of families live. The research is framed around the theory of domestication and based on 50 semi-structured interviews.1 “Domestication” is the process by which the household and its surroundings (both private and the public), together with the moral and formal or objective economy, are related to each other and become mutually constitutive (Silverstone, Hirsch and Morley 1999). The metaphor of “domestication” originally comes from the taming of wild animals, but has been usefully applied to the “domestication” of information communication technology (ICT), including television, within the home. Silverstone et al. (1999) have developed a range of concepts to capture this process, of which the best known are: “appropriation”, “objectification”, “incorporation” and “conversion”. These categories describe how the entry of ICT into the home is managed; how artefacts are physically (and symbolically) placed within the home; how they are adapted into everyday routines; and how they are displayed to others (Haddon 2007, 26). These four key concepts will be used in this chapter to discuss the importance of television within Portugal as an example of a small country in which there has been little research using this particular theoretical approach. Most studies on Portuguese television have focused on televisual history or come from research into trends in television consumption. The domestication theory is a holistic framework, useful to explain the meaning of television in Portuguese homes in all the stages of its presence in daily life. This forms part of a larger international project entitled Digital Inclusion and Participation: Comparing the Trajectories of Digital Media Use by Majority and Disadvantage Groups in Portugal and in the USA (UT Austin/Portugal Program).
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Let X be a finite or infinite chain and let be the monoid of all endomorphisms of X. In this paper, we describe the largest regular subsemigroup of and Green's relations on. In fact, more generally, if Y is a nonempty subset of X and is the subsemigroup of of all elements with range contained in Y, we characterize the largest regular subsemigroup of and Green's relations on. Moreover for finite chains, we determine when two semigroups of the type are isomorphic and calculate their ranks.
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A study of chemical transformations of cork during heat treatments was made using colour variation and FTIR analysis. The cork enriched fractions from Quercus cerris bark were subjected to isothermal heating in the temperature range 150–400 ◦C and treatment time from 5 to 90 min. Mass loss ranged from 3% (90 min at 150 ◦C) to 71% (60 min at 350 ◦C). FTIR showed that hemicelluloses were thermally degraded first while suberin remained as the most heat resistant component. The change of CIE-Lab parameters was rapid for low intensity treatments where no significant mass loss occurred (at 150 ◦C L* decreased from the initial 51.5 to 37.3 after 20 min). The decrease in all colour parameters continued with temperature until they remained substantially constant with over 40% mass loss. Modelling of the thermally induced mass loss could be made using colour analysis. This is applicable to monitoring the production of heat expanded insulation agglomerates.
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The effect of monopolar and bipolar shaped pulses in additional yield of apple juice extraction is evaluated. The applied electric field strength, pulsewidth, and number of pulses are assessed for both pulse types, and divergences are analyzed. Variation of electric field strength is ranged from 100 to 1300 V/cm, pulsewidth from 20 to 300 mu s, and the number of pulses from 10 to 200, at a frequency of 200 Hz. Two pulse trains separated by 1 s are applied to apple cubes. Results are plotted against reference untreated samples for all assays. Specific energy consumption is calculated for each experiment as well as qualitative indicators for apple juice of total soluble dry matter and absorbance at 390-nm wavelength. Bipolar pulses demonstrated higher efficiency, and specific energetic consumption has a threshold where higher inputs of energy do not result in higher juice extraction when electric field variation is applied. Total soluble dry matter and absorbance results do not illustrate significant differences between application of monopolar and bipolar pulses, but all values are inside the limits proposed for apple juice intended for human consumption.
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In this brief, a read-only-memoryless structure for binary-to-residue number system (RNS) conversion modulo {2(n) +/- k} is proposed. This structure is based only on adders and constant multipliers. This brief is motivated by the existing {2(n) +/- k} binary-to-RNS converters, which are particular inefficient for larger values of n. The experimental results obtained for 4n and 8n bits of dynamic range suggest that the proposed conversion structures are able to significantly improve the forward conversion efficiency, with an AT metric improvement above 100%, regarding the related state of the art. Delay improvements of 2.17 times with only 5% area increase can be achieved if a proper selection of the {2(n) +/- k} moduli is performed.
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The conquest of the West by the stagecoaches and then by railway, Ford and the automobile civilization, the Moon landing by Apollo 11, Microsoft, Apple, CNN, Google and Facebook have appeared to us as celebratory examples of the willingness and ability of the US to overcome the distance and the absence through so-called modern progress of transportation and communication. Undoubtedly, the imaginary and the instrumental power associated to transports and communication of the last century and a half are identified with the mental images that the world has of the US. A world that has eagerly imported and copy their technology and technological culture. Beyond the illusions, this attempting, which has always been praised to transcende space and eclipse the time to get to places and peole increasingly distant and fast, has always a dark side: the political control of population, commercial advertising, the spread of the rumors, noise and gossip. However, since at least the nineteenth century, the political project incorporated in modern transportation and communication technologies was not shared by some of the most remarkable thinkers in the US not only in that century, but also in the 20th century. This paper begins by rescue Ralph W. Emerson and Henry D. Thoreau legacy regarding to communication. Emerson conceived communication as a give-and-take with no coordination between the two, and does not involve contact with the other. Thoreau, in turn, argued that modern trasnportation and communications inventions are but pretty toys which distract attention from serious things, nothing more than 'improved means to an end that is not perfected.' Secondly, we show that this skeptical view of the techological improvement of transport and communication was proceed in an original way with James W. Carey, a media studies thinker who became known for his criticism of the transmission view of communication.
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Dissertação para a obtenção do grau de Mestre em Engenharia Electrotécnica Ramo de Energia
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We present results, obtained by means of an analytic study and a numerical simulation, about the resonant condition necessary to produce a Localized Surface Plasmonic Resonance (LSPR) effect at the surface of metal nanospheres embedded in an amorphous silicon matrix. The study is based on a Lorentz dispersive model for a-Si:H permittivity and a Drude model for the metals. Considering the absorption spectra of a-Si:H, the best choice for the metal nanoparticles appears to be aluminium, indium or magnesium. No difference has been observed when considering a-SiC:H. Finite-difference time-domain (FDTD) simulation of an Al nanosphere embedded into an amorphous silicon matrix shows an increased scattering radius and the presence of LSPR induced by the metal/semiconductor interaction under green light (560 nm) illumination. Further results include the effect of the nanoparticles shape (nano-ellipsoids) in controlling the wavelength suitable to produce LSPR. It has been shown that is possible to produce LSPR in the red part of the visible spectrum (the most critical for a-Si:H solar cells applications in terms of light absorption enhancement) with aluminium nano-ellipsoids. As an additional results we may conclude that the double Lorentz-Lorenz model for the optical functions of a-Si:H is numerically stable in 3D simulations and can be used safely in the FDTD algorithm. A further simulation study is directed to determine an optimal spatial distribution of Al nanoparticles, with variable shapes, capable to enhance light absorption in the red part of the visible spectrum, exploiting light trapping and plasmonic effects. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.