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171.
Understanding complex cognitive systems: the role of space in the organisation of collaborative work
This paper aims to provide some insights about the role of space as computational resource in collaborative practices. Focusing on collaborative design activity within a consulting firm in the UK, this research employs ethnographically inspired methods to investigate collaborative work. The paper is organised in seven main sections: introduction, previous work, theoretical framework, research methodology, findings, discussion and technological implications. The introduction provides an illustration of the area tackled in this work highlighting the relevance of context in human behaviour. Considering a collaborative activity as a socio-technical unit of analysis, the literature review presents alternative approaches to information processing. Extended cognition is then introduced as theoretical tool. The methodological section illustrates the ethnographically oriented methods for the data collection. The findings are then discussed according to a twofold structure summarising the features that space has in collaboration: (1) conversational support and creation of narratives and (2) cognitive scaffolding. The discussion raises issues that transcend the observations of design activity and extend the debate to the analysis of collaboration. These considerations then contribute to a reflection on the design of new technology for group support.(This work was conducted whilst Kenton OHara was working at The Appliance Studio, Bristol, UK) 相似文献
172.
Somatic cell nuclear transfer in horses: effect of oocyte morphology, embryo reconstruction method and donor cell type 总被引:5,自引:0,他引:5
Lagutina I Lazzari G Duchi R Colleoni S Ponderato N Turini P Crotti G Galli C 《Reproduction (Cambridge, England)》2005,130(4):559-567
The objective of the present work was to investigate and clarify the factors affecting the efficiency of somatic cell nuclear transfer (NT) in the horse, including embryo reconstruction, in vitro culture to the blastocyst stage, embryo transfer, pregnancy monitoring and production of offspring. Matured oocytes, with zona pellucida or after zona removal, were fused to cumulus cells, granulosa cells, and fetal and adult fibroblasts, and fused couplets were cultured in vitro. Blastocyst development to Day 8 varied significantly among donor cells (from 1.3% to 16%, P < 0.05). In total, 137 nuclear transfer-embryos were transferred nonsurgically to 58 recipient mares. Pregnancy rate after transfer of NT-embryos derived from adult fibroblasts from three donor animals was 24.3% (9/37 mares transferred corresponding to 9/101 blastocysts transferred), while only 1/18 (5.6%) of NT-blastocysts derived from one fetal cell line gave rise to a pregnancy (corresponding to 1/33 blastocysts transferred). Overall, seven pregnancies were confirmed at 35 days, and two went to term delivering two live foals. One foal died 40 h after birth of acute septicemia while the other foal was healthy and is currently 2 months old. These results indicate that (a) the zona-free method allows high fusion rate and optimal use of equine oocytes, (b) different donor cell cultures have different abilities to support blastocyst development, (c) blastocyst formation rate does not correlate with pregnancy fate and (d) healthy offspring can be obtained by somatic cell nuclear transfer in the horse. 相似文献
173.
A comparison between 13C NMR spectra of polymer solutions and Fourier transform infrared spectra of polymer films for several ethene-butadiene copolymers, including most butadiene as 1,2-cyclopropane and 1,2-cyclopentane units, is presented. This spectral comparison, also with the help of a low-molecular-mass model compound specifically synthesized for this purpose, has allowed to locate infrared absorbances associated with the cyclic comonomer units. In particular, a satisfactory calibration curve for evaluation of the amount of the reactive cyclopropane units, from the absorbance of the 1020 cm−1 band, has been achieved. An analysis of 1,2-cyclopropane unit reactivity in annealed films, has also pointed out that the presence of remnants of the polymerization catalyst can produce large increase in cyclopropane reactivity. 相似文献
174.
Mermelstein Catherine Blank; Rucker Naomi Gabriella 《Canadian Metallurgical Quarterly》1979,10(3):270
Discusses the application process for clinical psychology internships, focusing particularly on the areas of applications, interviews and notification. The authors offer suggestions to address problems with these areas of the application process. Regarding applications, devising a standard application form to be used by all programs would alleviate much of the burden students must now handle. An ethical code needs to be drawn up defining appropriate interviewing procedure and conduct. The solution for the difficulties involved in notification is the implementation of a computerized matching program, such as that used for medical internships. The authors suggest that these are major changes and would require much effort and expense to actualize, but they sincerely feel they would greatly improve the application procedure, making it both more efficient and less painful. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
175.
Cavallini G Parentini I Di Stefano R Maccheroni M Masini M Pollera M Gori Z Mosca F Bergamini E 《Lipids》2002,37(9):913-916
Dolichol (D) levels increase dramatically in older tissue. An understanding of the exchangeability of D between tissues may
be essential in order to understand the mechanism of the abnormal accumulation associated with aging. The question was investigated
by the use of organ transplantation. D-poor hearts donated by 3-mon-old and D-rich by 22-mon-old male Lewis rats were transplanted
heterotopically in 3-mon-old syngenic recipients, whose peripheral tissues and liver were poor in D. Native and transplanted
hearts were taken 7 and 21 d after surgery. Native hearts of 3-mon- and 22-mon-old male Lewis rats served as control. D concentration
and quantity were higher in older than in younger native hearts as expected. In the transplanted hearts, the quantity of D
was unchanged, irrespective of the age of the donor and of the time of transplantation, whereas D concentration increased
because of the remarkable disuse atrophy. No changes in D were observed in recipients’ tissues. It is concluded that dolichol
is not redistributed via circulation from the transplanted heart to the tissues and liver of the younger recipient. 相似文献
176.
Markham Rebecca G.; Toth Gabriella; Lickliter Robert 《Canadian Metallurgical Quarterly》2006,120(6):1315
Neonatal studies suggest elevated arousal can negatively influence perceptual and cognitive processes during early development. The authors explored this issue during the prenatal period by pharmacologically elevating physiological arousal in bobwhite quail (Colinus virginianus) embryos during exposure to a maternal call, then assessing preference for the familiar call following hatching. Embryos receiving norepinephrine showed a prenatal elevation in heart rate and failed to demonstrate a preference for the familiar call following hatching. Embryos not receiving norepinephrine showed no elevation in heart rate and demonstrated a preference for the familiar call. These results indicate elevated arousal can interfere with perceptual learning during the prenatal period and provide additional evidence for an optimal window of arousal necessary to foster species-typical perceptual functioning during early development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
177.
Parametric studies and identification problems require to perform repeated analyses, where only a few input parameters are
varied among those defining the problem of interest, often associated to complex numerical simulations. In fact, physical
phenomena relevant to several practical applications involve coupled material and geometry non-linearities. In these situations,
accurate but expensive computations, usually carried out by the finite element method, may be replaced by numerical procedures
based on proper orthogonal decomposition combined with radial basis function interpolation. Besides drastically reducing computing
times and costs, this approach is capable of retaining the essential features of the considered system responses while filtering
most disturbances. These features are illustrated in this paper with specific reference to some elastic–plastic problems.
The presented results can however be easily extended to other meaningful engineering situations. 相似文献
178.
Gabriella Bognár 《Computers & Mathematics with Applications》2011,61(8):2256-2261
Analytic solutions to similarity boundary layer equations are given for boundary layer flows of Newtonian fluid over a stretching wall with power law stretching velocity. The existence of analytic solutions is proven. The Crane’s solution is generalized and recurrence relations are obtained for the determination of coefficients of the exponential series. 相似文献
179.
Kousta Stavroula-Thaleia; Vigliocco Gabriella; Vinson David P.; Andrews Mark; Del Campo Elena 《Canadian Metallurgical Quarterly》2011,140(1):14
Although much is known about the representation and processing of concrete concepts, knowledge of what abstract semantics might be is severely limited. In this article we first address the adequacy of the 2 dominant accounts (dual coding theory and the context availability model) put forward in order to explain representation and processing differences between concrete and abstract words. We find that neither proposal can account for experimental findings and that this is, at least partly, because abstract words are considered to be unrelated to experiential information in both of these accounts. We then address a particular type of experiential information, emotional content, and demonstrate that it plays a crucial role in the processing and representation of abstract concepts: Statistically, abstract words are more emotionally valenced than are concrete words, and this accounts for a residual latency advantage for abstract words, when variables such as imageability (a construct derived from dual coding theory) and rated context availability are held constant. We conclude with a discussion of our novel hypothesis for embodied abstract semantics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献