180 resultados para linton


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A novel.

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Mode of access: Internet.

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At head of title: University of Liverpool.

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WHEN MEDIA ARE NEW: UNDERSTANDING THE DYNAMICS OF NEW MEDIA ADOPTION AND USE, JOHN CAREY AND MARTIN C. J. ELTON (2010) Ann Arbor, MI: University of Michigan Press (374 pp.), ISBN 978-0-472-05085-7, $47.50 (paperback). YOU ARE NOT A GADGET: A MANIFESTO, JARON LANIER (2011) New York: Vintage (240 pp.), ISBN 978-0307389978, $15 (paperback) EXTRAORDINARY CANADIANS: MARSHALL McLUHAN, DOUGLAS COUPLAND (2010) Toronto, Canada: Penguin Canada (208 pp.), ISBN 9780670069224, $26 (hardback)

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Structural evidence has demonstrated that P-glycoprotein (P-gp) undergoes considerable conformational changes during catalysis, and these alterations are important in drug interaction. Knowledge of which regions in P-gp undergo conformational alterations will provide vital information to elucidate the locations of drug binding sites and the mechanism of coupling. A number of investigations have implicated transmembrane segment six (TM6) in drug-P-gp interactions, and a cysteine-scanning mutagenesis approach was directed to this segment. Introduction of cysteine residues into TM6 did not disturb basal or drug-stimulated ATPase activity per se. Under basal conditions the hydrophobic probe coumarin maleimide readily labeled all introduced cysteine residues, whereas the hydrophilic fluorescein maleimide only labeled residue Cys-343. The amphiphilic BODIPY-maleimide displayed a more complex labeling profile. The extent of labeling with coumarin maleimide did not vary during the catalytic cycle, whereas fluorescein maleimide labeling of F343C was lost after nucleotide binding or hydrolysis. BODIPY-maleimide labeling was markedly altered during the catalytic cycle and indicated that the adenosine 5'-(beta,gamma-imino)triphosphate-bound and ADP/vanadate-trapped intermediates were conformationally distinct. Our data are reconciled with a recent atomic scale model of P-gp and are consistent with a tilting of TM6 in response to nucleotide binding and ATP hydrolysis.

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Our aim is to provide molecular understanding of the mechanisms underlying the (i) interaction between the two nucleotide binding domains (NBDs) and (ii) coupling between NBDs and transmembrane domains within P-glycoprotein (Pgp) during a transport cycle. To facilitate this, we have introduced a number of unique cysteine residues at surface exposed positions (E393C, S452C, I500C, N508C, and K578C) in the N-terminal NBD of Pgp, which had previously been engineered to remove endogenous cysteines. Positions of the mutations were designed using a model based on crystallographic features of prokaryotic NBDs. The single cysteine mutants were expressed in insect cells using recombinant baculovirus and the proteins purified by metal affinity chromatography by virtue of a polyhistidine tag. None of the introduced cysteine residues perturbed the function of Pgp as judged by the characteristics of drug stimulated ATP hydrolysis. The role of residues at each of the introduced sites in the catalytic cycle of Pgp was investigated by the effect of covalent conjugation with N-ethyl-maleimide (NEM). All but one mutation (K578C) was accessible to labeling with [3H]-NEM. However, perturbation of ATPase activity was only observed for the derivitized N508C isoform. The principle functional manifestation was a marked inhibition of the "basal" rate of ATP hydrolysis. Neither the extent nor potency to which a range of drugs could affect the ATPase activity were altered in the NEM conjugated N508C isoform. The results imply that the accessibility of residue 508, located in the alpha-helical subdomain of NBD1 in Pgp, is altered by the conformational changes that occur during ATP hydrolysis.

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Our jury system is predicated upon the expectation that jurors engage in systematic processing when considering evidence and making decisions. They are instructed to interpret facts and apply the appropriate law in a fair, dispassionate manner, free of all bias, including that of emotion. However, emotions containing an element of certainty (e.g., anger and happiness, which require little cognitive effort in determining their source) can often lead people to engage in superficial, heuristic-based processing. Compare this to uncertain emotions (e.g., hope and fear, which require people to seek out explanations for their emotional arousal), which instead has the potential to lead them to engage in deeper, more systematic processing. The purpose of the current research is in part to confirm past research (Tiedens & Linton, 2001; Semmler & Brewer, 2002) that uncertain emotions (like fear) can influence decision-making towards a more systematic style of processing, whereas more certain emotional states (like anger) will lead to a more heuristic style of processing. Studies One, Two, and Three build upon this prior research with the goal of improving methodological rigor through the use of film clips to reliably induce emotions, with awareness of testimonial details serving as measures of processing style. The ultimate objective of the current research was to explore this effect in Study Four by inducing either fear, anger, or neutral emotion in mock jurors, half of whom then followed along with a trial transcript featuring eight testimonial inconsistencies, while the other participants followed along with an error-free version of the same transcript. Overall rates of detection for these inconsistencies was expected to be higher for the uncertain/fearful participants due to their more effortful processing compared to certain/angry participants. These expectations were not fulfilled, with significant main effects only for the transcript version (with or without inconsistencies) on overall inconsistency detection rates. There are a number of plausible explanations for these results, so further investigation is needed.

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Analysis of the word lancea, of Hispanic origin after Varro, and of place names, people´s names and personal names derived from it. It confirms that the spear was the most important weapon in the Bronze Age, belonging to the iuventus and used as heroic and divine symbol. This analysis confirms also the personality of the Lusitanians, a people related to the Celts but with more archaic archaeological, linguistic and cultural characteristics originated in the tradition of the Atlantic Bronze in the II millennium BC. It is also relevant to better know the organisation of Broze and Iron Age societies and the origin of Indo-Europeans peoples in Western Europe and of pre-Roman peoples of Iberia.

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This paper explores the relationship between the rise of “new” social movements (15-M and Occupy) and the Internet. The new social media gives rise to new kinds of social movements  which embed this technology from the moment of conception. The future of social movements will be characterised by movinets, which will have the effect of developing new efficient ways of activism. The movinets, with their embedded technology and capacity to circulate ideas among different spheres of reality, have a potential to alter the dynamics of social mobilisation.

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The aim of this study was to develop a multiplex loop-mediated isothermal amplification (LAMP) method capable of detecting Escherichia coli generally and verocytotoxigenic E. coli (VTEC) specifically in beef and bovine faeces. The LAMP assay developed was highly specific (100%) and able to distinguish between E. coli and VTEC based on the amplification of the phoA, and stx1 and/or stx2 genes, respectively. In the absence of an enrichment step, the limit of detection 50% (LOD50) of the LAMP assay was determined to be 2.83, 3.17 and 2.83-3.17 log CFU/g for E. coli with phoA, stx1 and stx2 genes, respectively, when artificially inoculated minced beef and bovine faeces were tested. The LAMP calibration curves generated with pure cultures, and spiked beef and faeces, suggested that the assay had good quantification capability. Validation of the assay, performed using retail beef and bovine faeces samples, demonstrated good correlation between counts obtained by the LAMP assay and by a conventional culture method, but suggested the possibility of false negative LAMP results for 12.5-14.7% of samples tested. The multiplex LAMP assay developed potentially represents a rapid alternative to culture for monitoring E.coli levels in beef or faeces and it would provide additional information on the presence of VTEC. However, some further optimisation is needed to improve detection sensitivity.

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el libro ha sido organizado en tres partes. Una primera se ocupará de relatar las experiencias prácticas de funcionamiento del “dinero libre”, es decir, de medios de cambio alternativos o complementarios al dinero ofcial. En ella se describirán los experimentos de los años treinta como consecuencia de la Gran Depresión, incluidos algunos antecedentes), así como los de la posguerra, especialmente los iniciados durante la década pasada. En la segunda, estudiaremos las bases conceptuales y teóricas desarrolladas por economistas y otros pensadores sociales a lo largo de la historia y que generalmente han inspirado o servido de sustento para implementar los experimentos monetarios descritos a lo largo de la primera parte. La lista de autores "clásicos" sobre la materia abarca representantes de escuelas económicas tan variadas como la mercantilista (Boisguilbert), la de los socialistas utópicos (Proudhon), la de una facción de la anarquista (Gesell). la monetarista (Irving Fisher), la austríaca (Hayek) y la keynesiana (aparte del propio Keynes. Dudley Dillard): mientras que los más importantes autores contemporáneos incluyen a todo un heterogéneo "ejército de herejes" (en el sentido de Keynes) desconocidos -para los economistas ortodoxos- como Edgar Cann, Helmut Creutz, William Darity. Thomas Estermann. Paul Glover. Thomas Greco. Matina Hámmerli. Michel Herland. John Hotson. Margrit Kennedy. Bernard Litaer. Michael Linton. Wemer Onken, Edwin Riegel, Wemer Rosenberger. Klaus Schmitt. Lewis Solomon. Dieter Suhr, Robert Swann y Susan Witt. entre otros . Finalmente, analizaremos las características y las posibilidades teórico-prácticas de aplicar ese heterodoxo esquema monetario a escala nacional, tarea que hasta ahora no se ha intentado en país alguno. A lo largo de la parte tercera y final de este ensayo, indudablemente la más atractiva (pero también la más arriesgada), analizaremos las posibilidades de aplicación de estos esquemas monetarios al caso peruano a niveles subnacionales, enfatizando su viabilidad para los ámbitos locales. Luego de analizar la actual modalidad de acumulación y el sistema financiero del Perú y sus consecuencias, esbozaremos algunos lineamientos generales que podrían ser de utilidad -considerando las especificidades del espacio al que se aplicarían- para elaborar un programa general y proyectos-piloto para diversos ámbitos, los que específicamente podrían abarcar los espacios más disímiles: desde la macrourbe Lima-Metropolitana o su Cono Norte, pasando por la región Inka o la ciudad de Huancayo, hasta llegar a un pueblo como Mala o Chincheros, sólo a manera de ejemplo e ilustración por el momento.

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This is a long-term study of the use of information and communication technologies by 30 older adults (ages 70–97) living in a large retirement community. The study spanned the years of 1996 to 2008, during which time the research participants grappled with the challenges of computer use while aging 12 years. The researcher, herself a ‘mature learner,’ used a qualitative research design which included observations and open-ended interviews. Using a strategy of “intermittent immersion,” she spent an average of two weeks per visit on site and participated in the lives of the research population in numerous ways, including service as their computer tutor. With e-mail and telephone contact, she was able to continue her interactions with participants throughout the 12-year period. A long-term perspective afforded the view of the evolution, devolution or cessation of the technology use by these older adults, and this process is chronicled in detail through five individual “profiles.” Three research questions dominated the inquiry: What function do computers serve in the lives of older adults? Does computer use foster or interfere with social ties? Is social support necessary for success in the face of challenging learning tasks? In answer to the first question, it became clear that computers were valued as a symbol of competence and intelligence. Some individuals brought their computers with them when transferred to the single-room residences of assisted living or nursing care facilities. Even when use had ceased, their computers were displayed to signal that their owners were or had once been keeping up to date. In answer to the second question, computer owners socialized around computing use (with in-person family members or friends) more than, or as much as, they socialized through their computers in the digital realm of the Internet. And in answer to the third question, while the existence of social support did facilitate computer exploration, more important was the social support network generated and developed among fellow computer users.

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En la presente investigación, se evaluó el efecto de adicionar nanopartículas de sílice a dos matrices cementes buscando establecer su influencia en las propiedades finales de dichos materiales. Para llevar a cabo esta evaluación, se adicionaron las nanopartículas en dosificaciones desde 0.30% - 5.0% en peso, con la finalidad de determinar la dosificación a la cual se obtienen los mejores resultados. Una de las conclusiones obtenidas de la presente investigación señala que al utilizar este tipo de materiales, el mayor reto a superar, es la correcta dispersión de las nanopartículas en las matrices cementantes, ya que de no asegurar dicha dispersión y debido a la alta energía superficial que poseen las nanopartículas, se presenta una tendencia natural a aglomerarse conformando así materiales de tamaños muy superiores a los que presentan en su estado original, perdiendo así la ventaja de su uso. Para prevenir este efecto y como resultado de la primera etapa de esta investigación, se propuso un método de mezclado en el cual se utilizó como dispersante un aditivo superplastificante (en adelante llamado SP) de base policarboxilato de calcio en dosificaciones de 0.5% en peso que se adicionó a ambas matrices cementantes. Los resultados obtenidos sugieren que algunas propiedades tales como la resistencia mecánica a la compresión, la resistencia a la flexión y sobre todo, la resistencia al ataque químico por sulfatos, se ven mejoradas mediante la adición de nanopartículas de sílice. Dicha mejoría se observó tanto en la matriz de cemento Portland como en la matriz de cemento sulfoaluminoso. Los resultados finales de la investigación mostraron que la resistencia mecánica a la compresión para un cemento Portland ordinario se mejoró hasta en un 40% a edad de 24 h cuando se adicionaron las nanopartículas en porcentaje de 0.50% en peso, sin embargo, los resultados al resto de las edades no presentaron mejoría. Para la matriz de cemento sulfoaluminoso (en adelante CSA), los mejores resultados se obtuvieron también con la dosificación de 0.50% en peso con relación al cemento, sin embargo, la mejoría no fue de la misma magnitud a la obtenida con la matriz de cemento Portland. Por otro lado, la resistencia al ataque químico por sulfatos presentó una mejoría de hasta un 80% para la matriz de cemento sulfoaluminoso cuando se adicionaron las nanopartículas de sílice. Este resultado sugiere que la matriz con nanopartículas presenta una mayor densificación propiciando por ende, un menor grado de porosidad.

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Our jury system is predicated upon the expectation that jurors engage in systematic processing when considering evidence and making decisions. They are instructed to interpret facts and apply the appropriate law in a fair, dispassionate manner, free of all bias, including that of emotion. However, emotions containing an element of certainty (e.g., anger and happiness, which require little cognitive effort in determining their source) can often lead people to engage in superficial, heuristic-based processing. Compare this to uncertain emotions (e.g., hope and fear, which require people to seek out explanations for their emotional arousal), which instead has the potential to lead them to engage in deeper, more systematic processing. The purpose of the current research is in part to confirm past research (Tiedens & Linton, 2001; Semmler & Brewer, 2002) that uncertain emotions (like fear) can influence decision-making towards a more systematic style of processing, whereas more certain emotional states (like anger) will lead to a more heuristic style of processing. Studies One, Two, and Three build upon this prior research with the goal of improving methodological rigor through the use of film clips to reliably induce emotions, with awareness of testimonial details serving as measures of processing style. The ultimate objective of the current research was to explore this effect in Study Four by inducing either fear, anger, or neutral emotion in mock jurors, half of whom then followed along with a trial transcript featuring eight testimonial inconsistencies, while the other participants followed along with an error-free version of the same transcript. Overall rates of detection for these inconsistencies was expected to be higher for the uncertain/fearful participants due to their more effortful processing compared to certain/angry participants. These expectations were not fulfilled, with significant main effects only for the transcript version (with or without inconsistencies) on overall inconsistency detection rates. There are a number of plausible explanations for these results, so further investigation is needed.