846 resultados para Schon (1983), calling this ‘knowing-in-action’


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The UK population of the Spotted Flycatcher Muscicapa striata has declined markedly in the last 30 years but there have been few recent studies of the species. This study examined the relationship between nest success and the predominant habitat type around Spotted Flycatcher nests in two contrasting areas of England. A breeding population in eastern England, a region where numbers of Spotted Flycatchers are known to have decreased dramatically in recent decades, was compared with another in southwest England, where numbers have remained stable or even increased. Whilst there was no difference in breeding success between the two study areas, there were significant differences between habitats, with garden nests more successful than those in farmland or woodland, at both egg and chick stages. Estimates of productivity per nesting attempt were also lower in farmland and woodland, with nests in gardens fledging twice as many chicks as those in either woodland or farmland. The proximate cause of lower success in farmland and woodland was higher nest predation rates during both egg and chick stages. In terms of nesting success, farmland and woodland appear to be similar in quality for this species, but both appear to be suboptimal habitats when compared with gardens, providing evidence of a problem on the breeding grounds for this species, in at least these two habitats.

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We have identified two mutations in the ace1 gene of Aphis gossypii that are associated with insensitivity of acetylcholinesterase (AChE) to carbamate and organophosphate insecticides. The first of these, S431F (equivalent to F331 in Torpedo californica), is associated with insensitivity to the carbamate insecticide pirimicarb in a range of A. gossypii clones. The S431F mutation is also found in the peach-potato aphid, Myzus persicae (Sulzer), and a rapid RFLP diagnostic allows the identification of individuals of both aphid species with a resistant genotype. This diagnostic further revealed the presence of S431 in several other pirimicarb-susceptible aphid species. The serine at this position in the wild-type enzyme has only been reported for aphids and provides a molecular explanation of why pirimicarb has a specific aphicidal action. A less specific insensitivity to a wide range of carbamates and organophosphates is associated with a second mutation, A302S (A201 in T. californica).

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Worldwide, the population is aging, with estimates of 1 billion people aged 60 y or over within the next 20 y. With aging comes a reduction in overall health and increased morbidity and mortality due to infectious disease. Mortality due to gastrointestinal infections is up to 400 times higher in the elderly compared with younger adults. Recent studies have shown that the gut microbiota changes in old age, with an increased number of bacterial groups represented in the predominant elderly gut microbiota. This change in species "evenness" coincides with parallel changes in immune function, diet, and lifestyle and may contribute to disease susceptibility and severity in old age. The intestinal microbiota may thus be identified as an important target for improving health through reduced disease risk. Here, the application of prebiotics, especially the inulin-type fructans, and synbiotics (prebiotics combined with efficacious probiotic strains) will be discussed in terms of microbiota modulation and impact on disease risk in the aged population. Recent human intervention studies have confirmed the microbiota modulatory capability of the inulin-type fructans in the elderly and there is some evidence for reduced risk of disease. However, there is a need for more and larger human intervention studies to determine the efficacy of prebiotics in the elderly, particularly studies that take advantage of recent high resolution analytical methodologies like metabonomics, to shed light on possible prebiotic mechanisms of action.

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In studies of prospective memory, recall of the content of delayed intentions is normally excellent, probably because they contain actions that have to be enacted at a later time. Action words encoded for later enactment are more accessible from memory than those encoded for later verbal report [Freeman, J.E., and Ellis, J.A. 2003a. The representation of delayed intentions: A prospective subject-performed task? Journal of Experimental Psychology: Learning, Memory, and Cognition, 29, 976-992.]. As this higher assessibility is lost when the intended actions have to be enacted during encoding, or when a motor interference task is introduced concurrent to intention encoding, Freeman and Ellis suggested that the advantage of to-be-enacted actions is due to additional preparatory motor operations during encoding. Accordingly, in a fMRI study with 10 healthy young participants, we investigated whether motor brain regions are differentially activated during verbal encoding of actions for later enactment with the right hand in contrast to verbal encoding of actions for later verbal report. We included an additional condition of verbal encoding of abstract verbs for later verbal report to investigate whether the semantic motor information inherent in action verbs in contrast to abstract verbs activates motor brain regions different from those involved in the verbal encoding of actions for later enactment. Differential activation for the verbal encoding of to-be-enacted actions in contrast to to-be-reported actions was found in brain regions known to be involved in covert motor preparation for hand movements, i.e. the postcentral gyrus, the precuneus, the dorsal and ventral premotor cortex, the posterior middle temporal gyrus and the inferior parietal lobule. There was no overlap between these brain regions and those differentially activated during the verbal encoding of actions in contrast to abstract verbs for later verbal report. Consequently, the results of this fMRI study suggest the presence of preparatory motor operations during the encoding of delayed intentions requiring a future motor response, which cannot be attributed to semantic information inherent to action verbs. (c) 2006 Elsevier B.V. All rights reserved.

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Since its discovery more than a decade ago [Wu et al., 1982; Rozengurt et al., 1983], the 80-87 kDa myristoylated a lanine-rich C-kinase substrate (80K/MARCKS) protein has attracted a great deal of attention from researchers interested in cell growth and tumour progression. However, despite its ubiquitous distribution, a definitive functional role for 80K/MARCKS has not been found. The purpose of this review is to describe the properties, distribution and regulation of 80K/MARCKS and to discuss some of the most recent findings, both from our laboratory and from others, that have suggested a functional role for this protein in modulating cell growth and tumour progression. Furthermore, I will present data from our laboratory that implicates 80K/MARCKS as a novel tumour suppressor in cells of melanocyte origin.

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The coordination of design is a multi-faceted problem in construction. In design interactions in particular the real-time coordination of design activity is a persistent concern. The use of objects to coordinate the activity of design is studied as this happens in interactions between an architect and a building user group, in a setting where maintaining awareness of the design situation is important. An account of ways in which this was accomplished and how design activity is coordinated through interactional practices is provided. The empirical analyses examine design interaction from an ethnomethodological/conversation analysis (EM/CA) informed perspective to examine: ways in which mutual orientation to design issues are accomplished, how objects can provide a resource for the recognition of the activities of others and ways in which objects might be observable as momentarily intelligible. Subtle interactional practices involving talk, gesture and gaze were some of the small ways in which mutual orientation to the design actions of others became observable. The production of actions sequentially, in response to another's action, marked the real-time coordination of design moves in this setting. The relevance of accounts of micro-interaction to develop understanding of design activity and how it is coordinated are considered.

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The increased frequency in reporting UK property performance figures, coupled with the acceptance of the IPD database as the market standard, has enabled property to be analysed on a comparable level with other more frequently traded assets. The most widely utilised theory for pricing financial assets, the Capital Asset Pricing Model (CAPM), gives market (systematic) risk, beta, centre stage. This paper seeks to measure the level of systematic risk (beta) across various property types, market conditions and investment holding periods. This paper extends the authors’ previous work on investment holding periods and how excess returns (alpha) relate to those holding periods. We draw on the uniquely constructed IPD/Gerald Eve transactions database, containing over 20,000 properties over the period 1983-2005. This research allows us to confirm our initial findings that properties held over longer periods perform in line with overall market performance. One implication of this is that over the long-term performance may be no different from an index tracking approach.

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Drawing on a unique database of office properties constructed for Gerald Eve by IPD, this paper examines the holding periods of individual office properties sold between 1983 and 2003. It quantifies the holding periods of sold properties and examines the relationship between the holding period and investment performance. Across the range of holding periods, excess returns (performance relative to the market) are evenly distributed. There are as many winners as there are losers. The distribution of excess returns over different holding periods is widely spread with the risk of under-performance greater over short holding periods. Over the longer term, excess performance is confined to a narrow range and individual returns are more likely to perform in line with the market as a whole.

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Ensemble clustering (EC) can arise in data assimilation with ensemble square root filters (EnSRFs) using non-linear models: an M-member ensemble splits into a single outlier and a cluster of M−1 members. The stochastic Ensemble Kalman Filter does not present this problem. Modifications to the EnSRFs by a periodic resampling of the ensemble through random rotations have been proposed to address it. We introduce a metric to quantify the presence of EC and present evidence to dispel the notion that EC leads to filter failure. Starting from a univariate model, we show that EC is not a permanent but transient phenomenon; it occurs intermittently in non-linear models. We perform a series of data assimilation experiments using a standard EnSRF and a modified EnSRF by a resampling though random rotations. The modified EnSRF thus alleviates issues associated with EC at the cost of traceability of individual ensemble trajectories and cannot use some of algorithms that enhance performance of standard EnSRF. In the non-linear regimes of low-dimensional models, the analysis root mean square error of the standard EnSRF slowly grows with ensemble size if the size is larger than the dimension of the model state. However, we do not observe this problem in a more complex model that uses an ensemble size much smaller than the dimension of the model state, along with inflation and localisation. Overall, we find that transient EC does not handicap the performance of the standard EnSRF.

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Recent evidence suggests that an area in the dorsal medial prefrontal cortex (dorsal nexus) shows dramatic increases in connectivity across a network of brain regions in depressed patients during the resting state;1 this increase in connectivity is suggested to represent hotwiring of areas involved in disparate cognitive and emotional functions.1, 2, 3 Sheline et al.1 concluded that antidepressant action may involve normalisation of the elevated resting state functional connectivity seen in depressed patients. However, the effects of conventional pharmacotherapy for depression on this resting state functional connectivity is not known and the effects of antidepressant treatment in depressed patients may be confounded by change in symptoms following treatment.

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The Back to the Future Trilogy incorporates several different generic elements, including aspects of the fifties teen movie, science fiction, comedy and the western. These different modes playfully intertwine with each other creating a complex world of repetitions, echoes and modulations. This essay seeks to interrogate the construction of generic elements and the play between them through a close analysis of a repeated performance. Genre is signalled through various strategies employed within the construction of mise-en-scène, a significant portion of this, as I would like to argue, is transmitted through performance. The material detail of a performance – incorporating gesture, movement, voice, and even surrounding elements such as costume – as well as the way it its presented within a film is key to the establishment, invocation and coherence of genre. Furthermore, attention to the complexity of performance details, particularly in the manner in which they reverberate across texts, demonstrates the intricacy of genre and its inherent mutability. The Back to the Future trilogy represents a specific interest in the flexibility of genre. Within each film, and especially across all three, aspects of various genres are interlaced through both visual and narrative detail, thus constructing a dense layer of references both within and without the texts. To explore this patterning in more detail I will interrogate the contribution of performance to generic play through close analysis of Thomas F. Wilson’s performance of Biff/Griff/Burford Tannen and his central encounter with Marty McFly (Michael J. Fox) in each film. These moments take place in a fifties diner, a 1980s retro diner and a saloon respectively, each space contributing the similarities and differences in each repetition. Close attention to Wilson’s performance of each related character, which contains both modulations and repetitions used specifically to place each film’s central generic theme, demonstrates how embedded the play between genres and their flexibility is within the trilogy.

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The paper presents research with small and medium enterprise (SME) owners who have participated in a leadership development programme. The primary focus of the paper is on learning transfer and factors affecting it, arguing that entrepreneurs must engage in ‘action’ in order to ‘learn’ and that under certain conditions they may transfer learning to their firm. The paper draws on data from 19 focus groups undertaken from 2010 to 2012, involving 51 participants in the LEAD Wales programme. It considers the literatures exploring learning transfer and develops a conceptual framework, outlining four areas of focus for entrepreneurial learning. Utilising thematic analysis, it describes and evaluates what (actual facts and information) and how (techniques, styles of learning) participants transfer and what actions they take to improve the business and develop their people. The paper illustrates the complex mechanisms involved in this process and concludes that action learning is a method of facilitating entrepreneurial learning which is able to help address some of the problems of engagement, relevance and value that have been highlighted previously. The paper concludes that the efficacy of an entrepreneurial learning intervention in SMEs may depend on the effectiveness of learning transfer.

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Yano Y, Cesar KR, Araujo M, Rodrigues Jr. AC, Andrade LC, Magaldi AJ. Aquaporin 2 expression increased by glucagon in normal rat inner medullary collecting ducts. Am J Physiol Renal Physiol 296: F54-F59, 2009. First published October 1, 2008; doi: 10.1152/ajprenal.90367.2008.-It is well known that Glucagon (Gl) is released after a high protein diet and participates in water excretion by the kidney, principally after a protein meal. To study this effect in in vitro perfused inner medullary collecting ducts (IMCD), the osmotic water permeability (Pf; mu m/s) at 37 degrees C and pH 7.4 in normal rat IMCDs (n = 36) perfused with Ringer/HCO(3) was determined. Gl (10(-7) M) in absence of Vasopressin (AVP) enhanced the Pf from 4.38 +/- 1.40 to 11.16 +/- 1.44 mu m/s (P < 0.01). Adding 10(-8), 10(-7), and 10(-6) M Gl, the Pf responded in a dose-dependent manner. The protein kinase A inhibitor H8 blocked the Gl effect. The specific Gl inhibitor, des-His(1)-[Glu(9)] glucagon (10(-7) M), blocked the Gl-stimulated Pf but not the AVP-stimulated Pf. There occurred a partial additional effect between Gl and AVP. The cAMP level was enhanced from the control 1.24 +/- 0.39 to 59.70 +/- 15.18 fm/mg prot after Gl 10(-7) M in an IMCD cell suspension. The immunoblotting studies indicated an increase in AQP2 protein abundance of 27% (cont 100.0 +/- 3.9 vs. Gl 127.53; P = 0.0035) in membrane fractions extracted from IMCD tubule suspension, incubated with 10(-6) M Gl. Our data showed that 1) Gl increased water absorption in a dose-dependent manner; 2) the anti-Gl blocked the action of Gl but not the action of AVP; 3) Gl stimulated the cAMP generation; 4) Gl increased the AQP2 water channel protein expression, leading us to conclude that Gl controls water absorption by utilizing a Gl receptor, rather than a AVP receptor, increasing the AQP2 protein expression.

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Endospermic legumes are abundant in tropical forests and their establishment is closely related to the mobilization of cell-wall storage polysaccharides. Endosperm cells also store large numbers of protein bodies that play an important role as a nitrogen reserve in this seed. In this work, a systems approach was adopted to evaluate some of the changes in carbohydrates and hormones during the development of seedlings of the rain forest tree Sesbania virgata during the period of establishment. Seeds imbibed abscisic acid (ABA), glucose and sucrose in an atmosphere of ethylene, and the effects of these compounds on the protein contents, alpha-galactosidase activity and endogenous production of ABA and ethylene by the seeds were observed. The presence of exogenous ABA retarded the degradation of storage protein in the endosperm and decreased alpha-galactosidase activity in the same tissue during galactomannan degradation, suggesting that ABA represses enzyme action. On the other hand, exogenous ethylene increased alpha-galactosidase activity in both the endosperm and testa during galactomannan degradation, suggesting an inducing effect of this hormone on the hydrolytic enzymes. Furthermore, the detection of endogenous ABA and ethylene production during the period of storage mobilization and the changes observed in the production of these endogenous hormones in the presence of glucose and sucrose, suggested a correlation between the signalling pathway of these hormones and the sugars. These findings suggest that ABA, ethylene and sugars play a role in the control of the hydrolytic enzyme activities in seeds of S. virgata, controlling the process of storage degradation. This is thought to ensure a balanced flow of the carbon and nitrogen for seedling development.

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Secondary xylem of fibrous cactus wood is characterized by short narrow vessel elements with both simple perforation plates and large intervessel pits, libriform septate fibers, and large rays. These are present in basal cactus taxa, as well as in many other groups of the family. In Cactoideae, the most diversified and most derived subfamily, there are remarkable variations found in the secondary xylem, with the more highly derived taxa containing the greatest water storage capacity. Unlignified parenchyma is one specialization found in the fibrous wood of cacti. We observed this tissue in the secondary xylem at the base of the sterns of several Brazilian endemic species of Arrojadoa, Melocactus, and Stephanocereus, all members of the tribe Cereeae. In Arrojadoa and Melocactus the unlignified parenchyma occurs in lines and bands amongst the axial and radial xylem elements, while in Stephanocereus it is mainly restricted to the rays and does not form bands. We address the adaptive importance of the unlignified parenchyma in the fibrous wood in tribe Cereeae and the family Cactaceae as a whole.