901 resultados para Braking In a Turn.


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This article studies alterations in the values, attitudes, and behaviors that emerged among U.S. citizens as a consequence of, and as a response to, the attacks of September 11, 2001. The study briefly examines the immediate reaction to the attack, before focusing on the collective reactions that characterized the behavior of the majority of the population between the events of 9/11 and the response to it in the form of intervention in Afghanistan. In studying this period an eight-phase sequential model (Botcharova, 2001) is used, where the initial phases center on the nation as the ingroup and the latter focus on the enemy who carried out the attack as the outgroup. The study is conducted from a psychosocial perspective and uses "social identity theory" (Tajfel & Turner, 1979, 1986) as the basic framework for interpreting and accounting for the collective reactions recorded. The main purpose of this paper is to show that the interpretation of these collective reactions is consistent with the postulates of social identity theory. The application of this theory provides a different and specific analysis of events. The study is based on data obtained from a variety of rigorous academic studies and opinion polls conducted in relation to the events of 9/11. In line with social identity theory, 9/11 had a marked impact on the importance attached by the majority of U.S. citizens to their identity as members of a nation. This in turn accentuated group differentiation and activated ingroup favoritism and outgroup discrimination (Tajfel & Turner, 1979, 1986). Ingroup favoritism strengthened group cohesion, feelings of solidarity, and identification with the most emblematic values of the U.S. nation, while outgroup discrimination induced U.S. citizens to conceive the enemy (al-Qaeda and its protectors) as the incarnation of evil, depersonalizing the group and venting their anger on it, and to give their backing to a military response, the eventual intervention in Afghanistan. Finally, and also in line with the postulates of social identity theory, as an alternative to the virtual bipolarization of the conflict (U.S. vs al-Qaeda), the activation of a higher level of identity in the ingroup is proposed, a group that includes the United States and the largest possible number of countries¿ including Islamic states¿in the search for a common, more legitimate and effective solution.

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Multisensory interactions have been documented within low-level, even primary, cortices and at early post-stimulus latencies. These effects are in turn linked to behavioral and perceptual modulations. In humans, visual cortex excitability, as measured by transcranial magnetic stimulation (TMS) induced phosphenes, can be reliably enhanced by the co-presentation of sounds. This enhancement occurs at pre-perceptual stages and is selective for different types of complex sounds. However, the source(s) of auditory inputs effectuating these excitability changes in primary visual cortex remain disputed. The present study sought to determine if direct connections between low-level auditory cortices and primary visual cortex are mediating these kinds of effects by varying the pitch and bandwidth of the sounds co-presented with single-pulse TMS over the occipital pole. Our results from 10 healthy young adults indicate that both the central frequency and bandwidth of a sound independently affect the excitability of visual cortex during processing stages as early as 30 msec post-sound onset. Such findings are consistent with direct connections mediating early-latency, low-level multisensory interactions within visual cortices.

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Since the turn of the century, tributaries to the Missouri River in western Iowa have entrenched their channels to as much as six times their original depth. This channel degradation is accompanied by widening as the channel side slopes become unstable and landslides occur. The deepening and widening of these streams have endangered about 25% of the highway bridges in 13 counties [Lohnes et al. 1980]. Grade stabilization structures have been recommended as the most effective remedial measure for stream degradation [Brice et al., 1978]. In western Iowa, within the last seven years, reinforced concrete grade stabilization structures have cost between $300,000 and $1,200,000. Recognizing that the high cost of these structures may be prohibitive in many situations, the Iowa Department of Transportation (Iowa DOT) sponsored a study at Iowa State University (ISU) to find low-cost alternative structures. This was Phase I of the stream degradation study. Analytical and laboratory work led to the conclusion that alternative construction materials such as gabions and soil-cement might result in more economical structures [Lohnes et al. 1980]. The ISU study also recommended that six experimental structures be built and their performance evaluated. Phase II involved the design of the demonstration structures, and Phase III included monitoring and evaluating their performance.

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Since the beginning of channel straightening at the turn of the century, the streams of western Iowa have degraded 1.5 to 5 times their original depth. This vertical degradation is often accompanied by increases in channel widths of 2 to 4 times the original widths. The deepening and widening of these streams has jeopardized the structural safety of many bridges by undercutting footings or pile caps, exposing considerable length of piling, and removing soil beneath and adjacent to abutments. Various types of flume and drop structures have been introduced in an effort to partially or totally stabilize these channels, protecting or replacing bridge structures. Although there has always been a need for economical grade stabilization structures to stop stream channel degradation and protect highway bridges and culverts, the problem is especially critical at the present time due to rapidly increasing construction costs and decreasing revenues. Benefits derived from stabilization extend beyond the transportation sector to the agricultural sector, and increased public interest and attention is needed.

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Prior the middle of the 90', interviewing participants in protest events was quiet rare. INdividual SUrveys in RAllies (INSURA) did enter the social researcher's usual toolkit only in the following decade after Favre, Fillieule and Mayer (1997) conducted such a survey with as a primary ambition to build a solid methodological framework that could be subsequently applied by other researchers. After some years of intensive use of INSURA, one is entitled to wonder whether that technique has fulfilled social researchers' hopes or not. In that paper, results of a collective work on alter-global rallies in Evian and Saint- Denis are used to answer three interrelated questions. Firstly, some basic methodological questions about how to collect data on crowds are adressed. What are the specific constraints of interviewing people at the very moment they are "expressing" a political opinion? What specific constraints result from the morphology of the covered events, that is to say, how to build a valid sampling frame? The authors then turn to a more general point about the questions that can be solved, or not, using that technique. Secondly it is the strenghts and weaknesses of INSURA in exploring the transnational dimension of alter global protests that is adressed. The authors show that INSURA is certainly well suited to explore the demographics of alter-global events, as well as relational networks of individuals and multiple belongings. On the contrary, it is assumed that organization networks and movement's boundaries are far more difficult to explore through that method, a fact that seriously limits international cross comparisons of events and movements based on that tool.

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The adaptive function of melanin-based coloration is a long-standing debate. A recent genetic model suggested that pleiotropy could account for covariations between pigmentation, behaviour, morphology, physiology and life history traits. We explored whether the expression levels of genes belonging to the melanocortin system (MC1R, POMC, PC1/3, PC2 and the antagonist ASIP), which have many pleiotropic effects, are associated with melanogenesis (through variation in the expression of the genes MITF, SLC7A11, TYR, TYRP1) and in turn melanin-based coloration. We considered the tawny owl (Strix aluco) because individuals vary continuously from light to dark reddish, and thus, colour variation is likely to stem from differences in the levels of gene expression. We measured gene expression in feather bases collected in nestlings at the time of melanin production. As expected, the melanocortin system was associated with the expression of melanogenic genes and pigmentation. Offspring of darker reddish fathers expressed PC1/3 to lower levels but tended to express PC2 to higher levels. The convertase enzyme PC1/3 cleaves the POMC prohormone to obtain ACTH, while the convertase enzyme PC2 cleaves ACTH to produce α-melanin-stimulating hormone (α-MSH). ACTH regulates glucocorticoids, hormones that modulate stress responses, while α-MSH induces eumelanogenesis. We therefore conclude that the melanocortin system, through the convertase enzymes PC1/3 and PC2, may account for part of the interindividual variation in melanin-based coloration in nestling tawny owls. Pleiotropy may thus account for the covariation between phenotypic traits involved in social interactions (here pigmentation) and life history, morphology, behaviour and physiology.

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Precession electron diffraction (PED) is a hollow cone non-stationary illumination technique for electron diffraction pattern collection under quasikinematicalconditions (as in X-ray Diffraction), which enables “ab-initio” solving of crystalline structures of nanocrystals. The PED technique is recently used in TEMinstruments of voltages 100 to 300 kV to turn them into true electron iffractometers, thus enabling electron crystallography. The PED technique, when combined with fast electron diffraction acquisition and pattern matching software techniques, may also be used for the high magnification ultra-fast mapping of variable crystal orientations and phases, similarly to what is achieved with the Electron Backscatter Diffraction (EBSD) technique in Scanning ElectronMicroscopes (SEM) at lower magnifications and longer acquisition times.

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Our understanding of how genotype determines phenotype in primary dystonia is limited. Familial young-onset primary dystonia is commonly due to the DYT1 gene mutation. A critical question, given the 30% penetrance of clinical symptoms in DYT1 mutation carriers, is why the same genotype leads to differential clinical expression and whether non-DYT1 adult-onset primary dystonia, with and without family history share pathophysiological mechanisms with DYT1 dystonia. This study examines the relationship between dystonic phenotype and the DYT1 gene mutation by monitoring whole-brain structure using voxel-based morphometry. We acquired magnetic resonance imaging data of symptomatic and asymptomatic DYT1 mutation carriers, of non-DYT1 primary dystonia patients, with and without family history and control subjects with normal DYT1 alleles. By crossing the factors genotype and phenotype we demonstrate a significant interaction in terms of brain anatomy confined to the basal ganglia bilaterally. The explanation for this effect differs according to both gene and dystonia status: non-DYT1 adult-onset dystonia patients and asymptomatic DYT1 carriers have significantly larger basal ganglia compared to healthy subjects and symptomatic DYT1 mutation carriers. There is a significant negative correlation between severity of dystonia and basal ganglia size in DYT1 mutation carriers. We propose that differential pathophysiological and compensatory mechanisms lead to brain structure changes in non-DYT1 primary adult-onset dystonias and DYT1 gene carriers. Given the range of age of onset, there may be differential genetic modulation of brain development that in turn determines clinical expression. Alternatively, a DYT1 gene dependent primary defect of motor circuit development may lead to stress-induced remodelling of the basal ganglia and hence dystonia.

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Through scientific discourse and reproductive technologies, the reproductive body and the maternal body continue to be constructed as ‘natural’. At the same time,these technologies have begun to blur the boundaries between what is consideredan acceptable reproductive body, and consequently an acceptable maternal body,and an unnatural or a socially undesireable one. As science purports to offerwomen greater control over how and when they choose to procreate, through methods which range between delaying or eliminating the possibility of contraception to those which extend the possibility of conception to postmenopausal or infertile women, these same procedures raise questions about thenature and ‘naturalness’ of reproduction. Added to these concerns are thesuitablility of the reproductive body as a maternal body. Consequently, and moreand more frequently, bodies which defy ideals about maternity and motherhoodemerge, and questions about what it means to mother are raised. Bodies whichcontest the construction of motherhood as natural are frequently represented asmonstrous or freakish, and the debate between science and nature is heightened.Hiromi Goto’s short story ‘Hopeful Monsters’ resists the construction of the‘natural’ maternal body by highlighting the way in which women’s bodies areshaped by scientific discourse. In turn, images of ‘monstrous’ mothers emerge andare challenged, suggesting the need to reimagine what it means to mother and whatit means to be a mother. Through reading a selection of the stories this paper willinterrogate possible alternatives to constructions of the ‘natural’ maternal body and motherhood, suggesting that the Goto’s ‘monsters’ are perhaps only monstrous as a result of scientific discourse which constructs them as such.

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Taking as its point of departure recent insights about the performative¦nature of genre, The Poetics and Politics of the American Gothic¦challenges the critical tendency to accept at face value that gothic¦literature is mainly about fear. Instead, Agnieszka Soltysik Monnet¦argues that the American Gothic, and gothic literature in general,¦is also about judgment: how to judge and what happens when¦judgment is confronted with situations that defy its limits.¦Poe, Hawthorne, Melville, Gilman, and James all shared a concern¦with the political and ideological debates of their time, but tended¦to approach these debates indirectly. Thus, Monnet suggests, while¦slavery and race are not the explicit subject matter of antebellum¦works by Poe and Hawthorne, they nevertheless permeate it through¦suggestive analogies and tacit references. Similarly, Melville, Gilman,¦and James use the gothic to explore the categories of gender and¦sexuality that were being renegotiated during the latter half of the¦century. Focusing on The Fall of the House of Usher, The Marble¦Faun, Pierre, The Turn of the Screw, and The Yellow Wallpaper,¦Monnet brings to bear minor texts by the same authors that further¦enrich her innovative readings of these canonical works. At the same¦time, her study persuasively argues that the Gothic's endurance¦and ubiquity are in large part related to its being uniquely adapted¦to rehearse questions about judgment and justice that continue to¦fascinate and disturb.

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Recent studies have shown that melanin-based coloration is associated with the ability to cope with stressful environments, potentially explaining why coloration covaries with anti-predator behaviours, boldness and docility. To investigate whether these relationships are consistent across species, we performed a study in the European kestrel (Falco tinnunculus). Similar to our results found previously in the barn owl (Tyto alba), nestling kestrels displaying a larger sub-terminal black tail band stayed on their back longer (tonic immobility test) and breathed at a lower rate than individuals with a smaller black band when handled. However, in contrast to barn owls, nestling kestrels with a larger black tail band were more aggressive and more agitated. Our results strengthen the hypothesis that melanin coloration is related to stress response and in turn to the reaction to predators, a very important personality trait (i.e. boldness).

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1. Wood ants (Formica paralugubris) incorporate large amounts of solidified conifer resin into their nest, which reduces the density of many bacteria and fungi and protects the ants against some detrimental micro-organisms. By inducing an environment unfavourable to pathogens, the presence of resin may allow workers to reduce the use of their immune system. 2. The present study tested the hypothesis that the presence of resin decreases the immune activity of wood ants. Specifically, three components of the humoral immune defences of workers kept in resin-rich and resin-free experimental nests (antibacterial, lytic, and prophenoloxidase activities) were compared. 3. The presence of resin was associated with reduced bacterial and fungal densities in nest material and with a small decrease in worker antibacterial and lytic activities. The prophenoloxidase activity was very low in all workers and was not affected by the presence of resin. 4. These results suggest that collective medication with resin reduces pathogen pressure, which in turn decreases the use of the inducible part of the immune system. More generally, the use of plant secondary compounds might be an efficient and economical way to fight pathogens.

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By analysing entry policies and regularisation procedures in Spain from the 1990s to 2007, this article examines how the mismatch between very restrictive immigration policies and increasing foreign labour demands translated into a model of illegal migration, which in turn gave rise to the need to carry out periodical regularisation drives. This double 'policy gap' between legality and reality, and between entry policies and regularisation procedures, is explained as a policy in itself and as a way to solve in practice the apparently unsolvable dilemma between the demands for closure and the insatiable demands for foreign workers.

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The remaining phosphorus (Prem) has been used for estimating the phosphorus buffer capacity (PBC) of soils of some Brazilian regions. Furthermore, the remaining phosphorus can also be used for estimating P, S and Zn soil critical levels determined with PBC-sensible extractants and for defining P and S levels to be used not only in P and S adsorption studies but also for the establishment of P and S response curves. The objective of this work was to evaluate the effects of soil clay content and clay mineralogy on Prem and its relationship with pH values measured in saturated NaF solution (pH NaF). Ammonium-oxalate-extractable aluminum exerts the major impacts on both Prem and pH NaF, which, in turn, are less dependent on soil clay content. Although Prem and pH NaF have consistent correlation, the former has a soil-PBC discriminatory capacity much greater than pH NaF.

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The application of high hydrostatic pressure (200 MPa) to meat batter just before sausage fermentation and the inoculation of starter culture were studied to improve the safety and quality of traditional Spanish fermented sausages (fuet and chorizo). Higher amounts of biogenic amines were formed in chorizo than in fuet. Without interfering with the ripening performance in terms of acidification, drying and proteolysis, hydrostatic pressure prevented enterobacteria growth but did not affect Gram-positive bacteria significantly. Subsequently, a strong inhibition of diamine (putrescine and cadaverine) accumulation was observed, but that of tyramine was not affected. The inoculated decarboxylase-negative strains, selected from indigenous bacteria of traditional sausages, were resistant to the HHP treatment, being able to lead the fermentation process, prevent enterococci development and significantly reduce enterobacteria counts. In sausages manufactured with either non-pressurized or pressurized meat batter, starter culture was the most protective measure against the accumulation of tyramine and both diamines.