bluuebunny/crossref_metadata_2025 huggingface dataset:
Eficacia del uso de tácticas de influencia social en la propaganda de marketing social
Authors: López-Sáez Mercedes , Bustillos Antonio
Published: February 2008

Se comprueba la eficacia en mensajes escritos de tres tácticas de influencia: “Un penique es suficiente”, “Validación social” y “Mixta” (ambas conjuntamente), con una condición de Control, para lograr donativos para una ONG. En el estudio I se utilizan sólo textos. En el estudio II, además, se incluye otra variable moduladora: una imagen que, dependiendo de la condición, suscitaba afectos positivos o negativos. Los resultados de ambos estudios conjuntos (N = 726) muestran que la imagen no afecta a la decisión de donar dinero, pero sí a la cantidad donada, siendo superior cuando se incluye una imagen que suscita afecto negativo (tristeza o culpa). El empleo de tácticas de influencia afecta a la predisposición a dar dinero y a la cantidad que se aportaría. La táctica más eficaz de las estudiadas en este contexto es la de “Un penique es suficiente”.
Mujeres candidatas: percepción pública del liderazgo femenino
Authors: D'Adamo Orlando , García-Beaudoux Virginia , Ferrari Gladys , Slavinsky Gabriel
Published: February 2008

El principal objetivo del presente trabajo es realizar una exploración de las percepciones que predominan entre la opinión pública acerca del liderazgo femenino y, específicamente, de las mujeres que presentan candidaturas para competir por cargos políticos electivos. En primer lugar, se efectúa una breve revisión de las investigaciones existentes en la literatura acerca del tema. A continuación, se presentan los resultados de un sondeo de opinión que aborda algunos aspectos cruciales de la problemática planteada, efectuado en el contexto de la campaña electoral para las elecciones presidenciales de 2007 en Argentina.
¿Qué teorías necesitamos en educación? Presentación del debate
Authors: Álvarez Amelia
Published: February 2008

Se plantea este debate ante lo que se percibe como un cierto desencanto en el mundo educativo respecto a los modelos teóricos, a veces contradictorios entre sí, que han venido subyaciendo en las sucesivas reformas curriculares, especialmente los procedentes de la psicología. El debate se configura en torno a cuatro preguntas que giran en torno a la validez de las teorías psicológicas para elaborar prescripciones educativas y si éstas pueden ser las mismas para todos los ámbitos culturales. Todas las contribuciones al debate coinciden en señalar que es necesario reformular una teoría-epistemología general de las ciencias humanas que supere la abrumadora fragmentación disciplinar y que sea capaz de dar cuenta de la complejidad que caracteriza a la acción humana, en particular y muy especialmente a la acción educativa.
El lugar de la teoría psicológica en la educación. Contribución al debate ¿Qué teorías necesitamos en educación?
Authors: Rodríguez-Arocho Wanda C.
Published: February 2008

En este trabajo elaboramos la tesis de que las teorías psicológicas no son simples esfuerzos por explicar el comportamiento humano sino que, por ser producciones culturales, crean los fenómenos que intentan explicar, confiriéndoles realidad. Una vez compartida socialmente esta producción guía las prácticas educativas con poca reflexión crítica con respecto a su origen y el alcance y limitaciones de sus aplicaciones e implicaciones. Argumentamos que dicha reflexión crítica, aunque difícil, es necesaria para una educación con sentido histórico-cultural.
Contribución al diálogo: tres reflexiones
Authors: Villarini-Jusino Ángel R.
Published: February 2008

Ante la necesidad de elaborar una ontologia general, consecuente con una ontologia de lo) humano y con una teoría de la formación humana, como base teórica de prácticas educativas orientadas a la emancipación humana, el autor argumenta que es necesario un trabajo de crítica previa sobre el concepto mismo de ontologia. La ontologia es acto y producto desde el cual el ser humano, histórica y culturalmente constituido, vive sus relaciones; aquello dentro de lo cual se mueve. Frente a este siempre moverse en la ontologia, el ser humano tiene la posibilidad de vivirla ingenuamente, simplemente reconocerla, o asumirla críticamente. Todo intento de elaboración ontológica desde una perspectiva critica debe reconocer no sólo las categorias con las cuales se elabora y de dónde las obtiene sino como éstas vienen determinadas histórico culturalmente y las valoraciones a las que sirven. Desde esta perspectiva el autor elabora el punto de vista conceptual y valorativo de la tradición educativa en la que se ubica: la del proyecto emancipador de la pedagogía latinoamericana que en el siglo XIX funda Eugenio María de Hostos.
La creación cultural y la educación como autoevolución. Comentarios al debate
Authors: del Río Pablo
Published: February 2008

Se continúa en este comentario valorando el desarrollo humano de cada nueva generación como un desarrollo no garantizado que exige la construcción de las funciones superiores y que puede concebirse como autodesarrollo o como evolución abierta. Los comentarios se centran especialmente en el proceso de autoevolución como ascesis cultural y como autoescritura, analizándolo según el modelo de “tres novelas (de la persona, de la cultura y de la humanidad) y relacionando el modelo con el problema de la universalidad del hecho humano.
The Stationary Frontal Wave Packet Spontaneously Generated in Mesoscale Dipoles
Authors: Viúdez Álvaro
Published: February 2008

Three-dimensional numerical simulations of rotating, statically and inertially stable, mesoscale flows show that wave packets, with vertical velocity comparable to that of the balanced flow, can be spontaneously generated and amplified in the frontal part of translating vortical structures. These frontal wave packets remain stationary relative to the vortical structure (e.g., in the baroclinic dipole, tripole, and quadrupole) and are due to inertia–gravity oscillations, near the inertial frequency, experienced by the fluid particles as they decelerate when leaving the large speed regions. The ratio between the horizontal and vertical wavenumbers depends on the ratio between the horizontal and vertical shears of the background velocity. Theoretical solutions of plane waves with varying wavenumbers in background flow confirm these results. Using the material description of the fields it is shown that, among the particles simultaneously located in the vertical column in the dipole’s center, the first ones to experience the inertia–gravity oscillations are those in the upper layer, in the region of the maximum vertical shear. The wave packet propagates afterward to the fluid particles located below.
Tropical Atlantic Decadal Oscillation and Its Potential Impact on the Equatorial Atmosphere–Ocean Dynamics: A Simple Model Study
Authors: Lee Sang-Ki , Wang Chunzai
Published: February 2008

Simple coupled atmosphere–ocean models are used to study the potential influence of the tropical Atlantic Ocean decadal oscillation on the equatorial Atlantic atmosphere–ocean dynamics. Perturbing the model tropical Atlantic at the extratropics (25°–30°) with a decadal frequency, interhemispheric SST dipole mode emerges due to the wind–evaporation–SST feedback. Near the equator, a cross-equatorial oceanic gyre develops owing to the dipole-induced wind stress curl. Once formed, this oceanic gyre transports surface water across the equator from the cold to the warm hemisphere in the western boundary region and from the warm to the cold hemisphere in the Sverdrup interior. Interestingly, this occurs during both the positive and negative phases of the dipole oscillation, thus producing a persistent positive zonal SST gradient along the equator. Bjerknes-type feedback later kicks in to further strengthen the equatorial SST anomaly. Eventually, this feature grows to a quasi-stationary stage sustaining the equatorial westerly wind anomalies, thus also causing the depression (uplift) of the equatorial thermocline in the east (west), a condition similar to the Atlantic Niño. The dynamic relationship between the dipole SST oscillation and the equatorial thermocline suggests that a strengthening (weakening) of the dipole mode corresponds to a weakening (strengthening) of the equatorial thermocline slope.
Eddy Modulation of Air–Sea Interaction and Convection
Authors: Cerovečki Ivana , Marshall John
Published: February 2008

Eddy modulation of the air–sea interaction and convection that occurs in the process of mode water formation is analyzed in simulations of a baroclinically unstable wind- and buoyancy-driven jet. The watermass transformation analysis of Walin is used to estimate the formation rate of mode water and to characterize the role of eddies in that process. It is found that diabatic eddy heat flux divergences in the mixed layer are comparable in magnitude, but of opposite sign, to the surface air–sea heat flux and largely cancel the direct effect of buoyancy loss to the atmosphere. The calculations suggest that mode water formation estimates based on climatological air–sea heat flux data and outcrops, which do not fully resolve ocean eddies, may neglect a large opposing term in the heat budget and are thus likely to significantly overestimate true formation rates. In Walin’s watermass transformation framework, this manifests itself as a sensitivity of formation rate estimates to the averaging period over which the outcrops and air–sea fluxes are subjected. The key processes are described in terms of a transformed Eulerian-mean formalism in which eddy-induced mean flow tends to cancel the Eulerian-mean flow, resulting in weaker residual mean flow, subduction, and mode water formation rates.
Brine-Driven Eddies under Sea Ice Leads and Their Impact on the Arctic Ocean Mixed Layer
Authors: Matsumura Yoshimasa , Hasumi Hiroyasu
Published: February 2008

Eddy generation induced by a line-shaped salt flux under a sea ice lead and associated salt transport are investigated using a three-dimensional numerical model. The model is designed to represent a typical condition for the wintertime Arctic Ocean mixed layer, where new ice formation within leads is known to be one of the primary sources of dense water. The result shows that along-lead baroclinic jets generate anticyclonic eddies at the base of the mixed layer, and almost all the lead-originated salt is contained inside these eddies. These eddies survive for over a month after closing of the lead and transport the lead-originated salt laterally. Consequently, the lead-origin salt settles only on the top of the halocline and is not used for increasing salinity of the mixed layer. Sensitivity experiments suggest that the horizontal scale of generated eddies depends only on the surface forcing and is proportional to the cube root of the total amount of salt input. This scaling of eddy size is consistent with a theoretical argument based on a linear instability theory. Parameterizing these processes would improve representation of the Arctic Ocean mixed layer in ocean general circulation models.
On Quadratic Bottom Drag, Geostrophic Turbulence, and Oceanic Mesoscale Eddies
Authors: Arbic Brian K. , Scott Robert B.
Published: February 2008

Many investigators have idealized the oceanic mesoscale eddy field with numerical simulations of geostrophic turbulence forced by a horizontally homogeneous, baroclinically unstable mean flow. To date such studies have employed linear bottom Ekman friction (hereinafter, linear drag). This paper presents simulations of two-layer baroclinically unstable geostrophic turbulence damped by quadratic bottom drag, which is generally thought to be more realistic. The goals of the paper are 1) to describe the behavior of quadratically damped turbulence as drag strength changes, using previously reported behaviors of linearly damped turbulence as a point of comparison, and 2) to compare the eddy energies, baroclinicities, and horizontal scales in both quadratic and linear drag simulations with observations and to discuss the constraints these comparisons place on the form and strength of bottom drag in the ocean. In both quadratic and linear drag simulations, large barotropic eddies develop with weak damping, large equivalent barotropic eddies develop with strong damping, and the comparison in goal 2 above is closest when the nondimensional friction strength parameter is of order 1. Typical values of the quadratic drag coefficient (cd ∼ 0.0025) and of boundary layer depths (Hb ∼ 50 m) imply that the quadratic friction strength parameter cdLd/Hb, where Ld is the deformation radius, may indeed be of order 1 in the ocean. Model eddies are realistic over a wider range of friction strengths when drag is quadratic, because of a reduced sensitivity to friction strength in that case. The quadratic parameter is independent of the mean shear, in contrast to the linear parameter. Plots of eddy length scales, computed from satellite altimeter data, versus mean shear and versus rough estimates of the friction strength parameters suggest that both linear and quadratic bottom drag may be active in the ocean. Topographic wave drag contains terms that are linear in the bottom flow, thus providing some justification for the use of linear bottom drag in models.
Mesoscale to Submesoscale Transition in the California Current System. Part II: Frontal Processes
Authors: Capet X. , McWilliams J. C. , Molemaker M. J. , Shchepetkin A. F.
Published: February 2008

This is the second of three papers investigating the regime transition that occurs in numerical simulations for an idealized, equilibrium, subtropical, eastern boundary, upwelling current system similar to the California Current. The emergent upper-ocean submesoscale fronts are analyzed from phenomenological and dynamical perspectives, using a combination of composite averaging and separation of distinctive subregions of the flow. The initiating dynamical process for the transition is near-surface frontogenesis. The frontal behavior is similar to both observed meteorological surface fronts and solutions of the approximate dynamical model called surface dynamics (i.e., uniform interior potential vorticity q and diagnostic force balance) in the intensification of surface density gradients and secondary circulations in response to a mesoscale strain field. However, there are significant behavioral differences compared to the surface-dynamics model. Wind stress acts on fronts through nonlinear Ekman transport and creation and destruction of potential vorticity. The strain-induced frontogenesis is disrupted by vigorous submesoscale frontal instabilities that in turn lead to secondary frontogenesis events, submesoscale vortices, and excitation of even smaller-scale flows. Intermittent, submesoscale breakdown of geostrophic and gradient-wind force balance occurs during the intense frontogenesis and frontal-instability events.
Dynamics of the Intraseasonal Oscillations in the Indian Ocean South Equatorial Current
Authors: Zhou Lei , Murtugudde Raghu , Jochum Markus
Published: February 2008

The spatial and temporal features of intraseasonal oscillations in the southwestern Indian Ocean are studied by analyzing model simulations for the Indo-Pacific region. The intraseasonal oscillations have periods of 40–80 days with a wavelength of ∼650 km. They originate from the southeastern Indian Ocean and propagate westward as Rossby waves with a phase speed of ∼25 cm s−1 in boreal winter and spring. The baroclinic instability is the main driver for these intraseasonal oscillations. The first baroclinic mode dominates during most of the year, but during boreal winter and spring the second mode contributes significantly and often equally. Consequently, the intraseasonal oscillations are relatively strong in boreal winter and spring. Whether the atmospheric intraseasonal oscillations are also important for forcing the oceanic intraseasonal oscillations in the southwestern Indian Ocean needs further investigation.
An Experimental Investigation of Internal Tide Generation by Two-Dimensional Topography
Authors: Peacock Thomas , Echeverri Paula , Balmforth Neil J.
Published: February 2008

Experimental results of internal tide generation by two-dimensional topography are presented. The synthetic Schlieren technique is used to study the wave fields generated by a Gaussian bump and a knife edge. The data compare well to theoretical predictions, supporting the use of these models to predict tidal conversion rates. In the experiments, viscosity plays an important role in smoothing the wave fields, which heals the singularities that can appear in inviscid theory and suppresses secondary instabilities of the experimental wave field.
Reevaluation of the Bulk Exchange Coefficient for Humidity at Sea during Unstable and Neutral Conditions
Authors: Sahlée Erik , Smedman Ann-Sofi , Högström Ulf , Rutgersson Anna
Published: February 2008

Processes influencing the air–sea exchange of humidity during unstable and neutral stratification were studied using tower measurements from the island of Östergarnsholm in the Baltic Sea. For small air–sea temperature differences, the neutral exchange coefficient for humidity CEN was found to increase with increasing wind speed, attaining a value of approximately 1.8 × 10−3 at 13 m s−1. The high CEN values were observed during situations when the characteristics of the turbulence structure differed from what would be expected from traditional theory. Results from spectral analysis point to a situation in which the vertical transport of humidity is dominated by smaller-scale eddies. Quadrant analysis showed that these eddies enhance the humidity flux by bringing down drier air from layers aloft. These findings are consistent with recent analyses of the neutral boundary layer in which a change of turbulence regime has been observed. The conclusion is made that this dynamic effect accounts for the observed increase in CEN. Here, CEN was calculated using a wave-dependent normalized wind gradient, which had the effect of reducing the value by about 10% during swell relative to calculations using a non-wave-dependent normalized wind gradient.
Toward a Unified Theory of Causality
Authors: Mahoney James
Published: February 2008

In comparative research, analysts conceptualize causation in contrasting ways when they pursue explanation in particular cases (case-oriented research) versus large populations (population-oriented research). With case-oriented research, they understand causation in terms of necessary, sufficient, INUS, and SUIN causes. With population-oriented research, by contrast, they understand causation as mean causal effects. This article explores whether it is possible to translate the kind of causal language that is used in case-oriented research into the kind of causal language that is used in population-oriented research (and vice versa). The article suggests that such translation is possible, because certain types of INUS causes manifest themselves as variables that exhibit partial effects when studied in population-oriented research. The article concludes that the conception of causation adopted in case-oriented research is appropriate for the population level, whereas the conception of causation used in population-oriented research is valuable for making predictions in the face of uncertainty.
Partisan Politics, the Welfare State, and Three Worlds of Human Capital Formation
Authors: Iversen Torben , Stephens John D.
Published: February 2008

The authors propose a synthesis of power resources theory and welfare production regime theory to explain differences in human capital formation across advanced democracies. Emphasizing the mutually reinforcing relationships between social insurance, skill formation, and spending on public education, they distinguish three distinct worlds of human capital formation: one characterized by redistribution and heavy investment in public education and industry-specific and occupation-specific vocational skills; one characterized by high social insurance and vocational training in firm-specific and industry-specific skills but less spending on public education; and one characterized by heavy private investment in general skills but modest spending on public education and redistribution. They trace the three worlds to historical differences in the organization of capitalism, electoral institutions, and partisan politics, emphasizing the distinct character of political coalition formation underpinning each of the three models. They also discuss the implications for inequality and labor market stratification across time and space.
Credible Power-Sharing and the Longevity of Authoritarian Rule
Authors: Magaloni Beatriz
Published: February 2008

To survive in office, dictators need to establish power-sharing arrangements with their ruling coalitions, which are often not credible. If dictators cannot commit to not abusing their “loyal friends”—those who choose to invest in the existing autocratic institutions rather than in forming subversive coalitions— they will be in permanent danger of being overthrown, both by members of the ruling elite and by outside rivals. This article explores the role of autocratic political parties and elections (both one-party and multiparty) in mitigating the commitment problem, making power-sharing between the dictator and his ruling coalition possible.
Prospects for the UK economy
Authors: Khoman Ehsan , Kirby Simon
Published: February 2008

Despite the turmoil in global financial markets during the second half of 2007, UK GDP continued to grow at a robust pace. The above trend growth of 2006 continued into the first three quarters of last year and the preliminary estimate of GDP growth shows only a limited moderation into the fourth quarter of last year (figure 1). This suggests we will see a growth rate of 3.1 per cent for 2007 as a whole, a slight acceleration from 2.9 per cent in 2006. This robust growth has been sustained by household consumption and, to a lesser extent, gross fixed investment.
Risk and the UK exchange rate
Authors: Barrell Ray , Holland Dawn
Published: February 2008

Sterling has fallen markedly against other currencies in the past few months, and in January reached its lowest point against the euro (or its equivalent) since the last quarter of 1996, as we can see from figure 1, which uses the first three weeks of January 2008 as an indicator of the value that will be achieved in the whole first quarter. Sterling has also weakened against the dollar in the past few months, although it remains at a high level. In effective terms, sterling fell on average by 2.5 per cent in the fourth quarter, and in early January it was more than 6 per cent lower than the average for the previous quarter. The fall was largely unanticipated, and the effective exchange rate for the first quarter of 2008 is more than 7 per cent below where we assumed it would be in October 2007.
Urban Teacher Commitment
Authors: Henkin Alan B. , Holliman Stephanie L.
Published: February 2008

This study explores relationships between teachers' organizational commitment and interpersonal conflict, participation activities beyond the classroom, and innovation in schools. Potential relationships among study variables are suggested in research that views affective commitment as a proxy measure for decisions to leave the school. Increments in experience in the profession are negatively associated with organizational commitment. Higher levels of interpersonal conflict are linked to lower levels of organizational commitment. Participation in activities beyond the classroom is marginally related to commitment, whereas support for innovation has a strong positive effect on teachers' commitment. Results, considered in context, suggest the importance of high levels of commitment and commitment norms in terms of the teachers' work performance and the stability of the professional workforce.
Bioavailability and Dose Proportionality of Intramuscular Diazepam Administered by Autoinjector
Authors: Lehmann Craig , Wannarka Gerald L.
Published: February 2008

A diazepam 10‐mg autoinjector was evaluated in bioequivalence and dose proportionality studies; both involved 24 young, healthy subjects and used randomized, open‐label, 2‐treatment, 2‐period crossover designs with a 3‐week washout period between treatments. The bioequivalence study compared a single diazepam 10‐mg autoinjector with a conventional needle and syringe containing 10 mg of diazepam injectable. The dose proportionality study compared the pharmacokinetics of a single diazepam 10‐mg autoinjector with that of 2 diazepam 10‐mg autoinjectors given simultaneously (20 mg). Injections were intramuscular in the midanterolateral thigh in both studies. The studies showed that the diazepam autoinjector produced consistent plasma diazepam levels, with a rapid onset of absorption. The diazepam 10‐mg autoinjector given intramuscularly was bioequivalent to a conventional syringe containing diazepam 10 mg. A single (10‐mg) autoinjector and 2 (20‐mg) diazepam autoinjectors administered simultaneously produced plasma diazepam concentrations that were essentially dose proportional.
Girls talk about dolls and boys about cars? Analyses of group and individual variation in Danish children's first words
Authors: Wehberg Sonja , Vach Werner , Bleses Dorthe , Thomsen Pia , Madsen Thomas O. , Basbøll Hans
Published: February 2008

Based on data from the Danish Longitudinal CDI study on 182 Danish children, we analyse aspects of variation in the children's first 100 words (produced). First, we demonstrate the effect of gender and birth order (number of siblings) on acquisition times of first words by identifying single words which are significantly earlier in the productive repertoire of, for instance, girls versus boys. We also investigate the effect of the same factors on the composition of the vocabulary where the definition of categories (word classes) is based on the CDI's thematic categorization. Finally, we investigate the individuality of the lexicon's composition and find time-persistent differences between children for some word classes at this early stage.
Toddlers' persistence when communication fails: Response motivation and goal substitution
Authors: Fagan Mary K.
Published: February 2008

Communicative breakdowns were created in response to toddlers' single-word requests by means of two feedback conditions: one involving goal substitution, the other stating explicitly that the speaker was not understood (i.e., `I don't know what you mean'). Participants were 15 children, ages 17—25 months. Children typically abandoned their original requests in response to goal substitution but revised or repeated their requests when confronted with `I don't know what you mean.' Thus, in the early stages of language development, toddlers' response persistence appeared to depend in large part upon motivation for goal attainment.
Dinner conversations with a trilingual two-year-old: Language socialization in a multilingual context
Authors: Quay Suzanne
Published: February 2008

Family dinner conversations can serve as a medium for the mutual involvement of children and parents in language socialization. In this study, early pragmatic development in a trilingual child is addressed from the perspective of the language dynamics of a multilingual family. How young children learn to adjust their speech to their interlocutors can be seen clearly in the language choices and the mixing patterns of the trilingual two-year-old. The child selected language(s) not only from the language(s) spoken to her but also with attention to her interlocutor's linguistic proficiencies and the language context in which she found herself along a monolingual to trilingual continuum. She shifted languages in family dinner conversations according to the norms established in the home.
Developmental differences in the effects of negative and positive evidence
Authors: Strapp Chehalis M. , Bleakney Dana M. , Helmick Augusta L. , Tonkovich Hayley M.
Published: February 2008

The current study sought to assess development differences in children's learning of irregular nouns and verbs under conditions of negative and positive evidence. Fifty-five 3-, 4- and 5-year-old children learned nonsense nouns and verbs and were later asked to produce plural forms for the nouns and past tense forms for the verbs. Forms were constructed to be irregular, and half were provided through negative evidence and half through positive evidence. Age, form (noun vs. verb) and evidence type (negative vs. positive) interacted: 3-year-olds learned more nouns through negative evidence t(15) = 2.76, p = 0.014, r2 = 0.34, while 5-year-olds learned more verbs through negative evidence t(16) = 2.281, p = 0.04, r2 = 0.25. Four-year-olds showed equal learning across the two conditions. These results suggest developmental differences in the efficacy of negative evidence.
Stories without Significance in the Discourse of Breast Reconstruction
Authors: Sandell Kerstin
Published: February 2008

Breast reconstruction is an everyday, apparently nonviolent, even benevolent, remaking of the normal, and the reasons for why reconstruction is motivated and legitimate are uncontroversial and widely accepted. In this article the author will, through Donna Haraway's way of conceptualizing discourses, analyze what she calls “stories without significance.” The author has mapped the stories and interpretations of women undergoing reconstruction, stories that are not becoming part of the monovocal discourse of breast reconstruction. Thus, she focuses on the things said that are not assigned significance, the silences and impossibilities. The article is also an effort to account for some of the invisible work that goes into the process of breast reconstruction in dialogue with the feminist field of science and technology studies. This to explore the (re)making of the normal in a medical practice and reflect on how modest interventions could be made.
Refashioning Bodies, Reshaping Agency
Authors: Goodwin Dawn
Published: February 2008

Poovey has argued that the anesthetized “unresisting body” can offer no impediment to a doctor's interpretation of its conduct. In contrast, drawing on ethnographic data of anesthetic practice, this article suggests that the technological augmentation of the body required by present-day anesthesia enhances the ability of an unconscious body to convey its needs and shape the course of the anesthetic. In analyzing the expressions of anesthesia's cyborgs, the author draws on Haraway, Latour, and Suchman to reconsider the characteristics of agency and how an unconscious body might “resist” or inform a doctor's interpretation. This attempt to explore the nature and distribution of agency within a collective is intended as a contribution to the debates surrounding medical dominance and those theorizing the role of technology in health care.
Nonreproductive Technologies
Authors: Harrington Jennifer , Becker Gay , Nachtigall Robert
Published: February 2008

This article examines the absence of biological relatedness in couples where the use of a third-party gamete donor casts doubt on the notion of conventional kinship. The authors observe that individuals who have used technology to create a family remediate relatedness through a dehistoricized idea of kinship in which the traditional concept is replaced with the concept of chance. The article also examines how inherited value is replaced by strategies that redefine the ways in which donor gamete parents can pass their values on to their children. This examination is accomplished by looking at how couples who used donated gametes articulate the ways in which familial relatedness is left open to chance.
Displacement and Emplacement of Health Technology
Authors: Lehoux Pascale , Poland Blake , Daudelin Geneviève , Holmes Dave , Andrews Gavin
Published: February 2008

The provision of “closer-to-patient” services has increased in most industrialized countries. However, the migration of services in non-traditional health care settings implies redefining the role of technical and human entities and transforming the nature and use of technologies and places. Drawing on various scholarly efforts to conceptualize space, place, and technology, this paper compares and contrasts satellite and mobile dialysis units implemented in two regions in the province of Quebec, Canada. The satellite units were hosted in two small, local hospitals where nursing staff had been recently trained. The mobile unit was a bus adapted to host five dialysis stations; nurses traveled back and forth between a university teaching hospital and two sites located within a radius of 7.6 miles. In both projects, nephrologists supervised from a distance via a videoconferencing system. Our aim is to illustrate the ways in which the displacement of technical and human entities gives shape to new forms of emplacement in non-traditional health care settings. The satellite and mobile units contributed to the culture of dialysis care and transformed the identity of nurses, doctors, patients, and technologies. By contrasting two projects involving different spatial and clinical logics, we analyze in what ways certain forms of recombination of human and technical entities can prove incomplete but nevertheless acceptable to providers and project managers.
Effect of Orientation of Fibers and Coupling Agent on Tensile Properties of Phenolic/Silica Composites
Authors: Rajulu A. Varada , Devi L. Ganga , Devi R. Rama
Published: February 2008

Phenolic/silica composites were prepared using PF-108 resol type phenolic resin and ISROSIL silica fabric as neat, and incorporating 3-aminopropyltriethoxysilane coupling agent. Composites were also made by changing the warp angle of the fibers in the fabric with the stress direction. The effect of orientation of fibers and the coupling agent on the properties of the composites was studied.
Semi-inverse Method for Vibration and Buckling of Axially Functionally Graded Beams
Authors: Aydogdu Metin
Published: February 2008

In this study, vibration and buckling of axially functionally graded simply supported beams is analyzed by using the semi-inverse method. Euler—Bernoulli beam theory was used in the analysis. By using a pre-specified frequency and buckling loads, variation of the Young's modulus in the axial direction is obtained in terms of the axial coordinate. It is found that the Young's modulus changes exponentially between the edges of the beam for the vibration and buckling problem.
Study of the Influence of Immersion on the Carbon Fiber/Epoxy Composites
Authors: Lv X.J. , Zhang Q. , Li X.F. , Xie G.J.
Published: February 2008

Carbon fiber/epoxy composites are studied in this paper. In order to decide the important factors in the performance of the composite materials, many corrosion tests were carried out by means of immersion. The test conditions were decided by the normal (orthogonal test) table of three factors, i.e. temperature, concentration and the test period. The results show that the immersion of the properties of composites deteriorated and that the solution temperature is the most important factor among the three factors.
Grafting of Acrylamide and Acrylic Acid onto Polyethylene Fiber for Improved Adhesion to Epoxy Resin
Authors: Amornsakchai Taweechai , Doaddara Onuma
Published: February 2008

Surface modification of polyethylene (PE) fiber via 2-stage grafting to improve its adhesion to epoxy resin was studied. The PE fiber was first functionalized by thermal decomposition of potassium peroxydisulfate to create grafting sites. In the second stage, functionalized fiber was grafted with acrylamide (AAm) and acrylic acid (AAc) monomer by Ceric (IV) ion technique. The adhesion of grafted fibers to epoxy resin was studied by a single fiber pull out test. Pull out strength increases about 2 folds after functionalization and 3.5 and 4.8 folds after grafting with AAm and AAc, respectively. The improvement in pull out strength after functionalization and grafting are due to physical interaction and the formation of chemical bonding, respectively. Traces of transfering materials on the surface of pulled out fiber suggested that failure could be due to cohesive failure of either epoxy resin or grafted layer. Preliminary study of surface grafted fiber/epoxy composite showed significant improvement in flexural and impact strength over unreinforced resin and untreated fiber reinforced composite.
Finite Element Modeling for Deflection and Bending Responses of GFRP Poles
Authors: Masmoudi R. , Mohamed H. , Metiche S.
Published: February 2008

The use of the tapered glass fiber-reinforced polymer (GFRP) poles are well recognized as an alternative for traditional materials such as wood, steel, and concrete, in overhead power lines and distribution aerial networks. The current research work aims to assess the general behaviors of lightweight GFRP poles structures. A nonlinear finite element (FE) analysis is carried out to address the nonlinear behavior of tapered GFRP poles under lateral loads. The numerical results of the program are verified with the experimental results conducted on full-scale GFRP poles. The GFRP poles are fabricated using the filament winding technique; E-glass fiber and Epoxy resin are utilized for manufacturing these poles. There is very satisfactory agreement between the numerical results and the experimental results in terms of load-deflection relationship and ultimate load carrying capacity. The FE model was used to detect the performance of GFRP poles having service openings (holes). Several FE simulations with different combinations of parameters, such as fiber orientation, number of layers and thickness of layers, were employed. Evaluation of the deflection and bending strength characteristics of GFRP Poles (20, 33, 35 and 40 ft height) are presented. Optimum new designs for three zones along the height of the GFRP poles are proposed, under equivalent wind load. The ultimate load carrying capacity and flexural stiffness are improved with a significant saving in the weight by utilizing this design.
Modeling and Analysis of Cutting Force in Turning of GFRP Composites by CBN Tools
Authors: Sarma P.M.M.S. , Karunamoorthy L. , Palanikumar K.
Published: February 2008

GFRP composites find diverse applications in many engineering fields. For certain applications, the use of composites rather than metals has in fact resulted in savings of both cost and weight. The usage in many fields demands several machining operations to be performed on GFRP composites. As such, the present paper investigates the effect of cutting force in the turning of GFRP pipes using CBN tools. Experiments are conducted on a lathe using the central composite design technique. A model is developed to correlate the cutting parameters with cutting force, using response surface methodology. The results indicate that the developed model is suitable for prediction of cutting forces in turning of GFRP composites. The effect of different parameters on cutting forces are analyzed and presented in this study.
Preparation and Dielectric Characterization of Nanosized Fe2O3 Doped Methylsilicone Resin/Glass Fiber Compositions
Authors: Min Chun-Ying , Huang Yu-Dong , Li Liu
Published: February 2008

Nanosized Fe2O3 doped methylsilicone resin/glass fiber composites have been successfully synthesized and the resulting composites were characterized by Fourier-transformed infrared (FT-IR), scanning electron microscopy (SEM) and spatially resolved energy-dispersive X-ray spectroscopy (EDS). The result of dielectric measurement shows that the doping of Fe 2O3 nanoparticles is beneficial to the improvement of the dielectric properties of the methylsilicone resin/ glass fiber compositions. The elementary analysis of the composites at different temperatures was conducted, indicating that nanosized Fe2O3 is an excellent high-temperature decarbonizer for methylsilicone resin.
Processing of Nanoclay Filled Sandwich Composites and their Response to Impact Loading
Authors: Hosur M.V. , Mohammed A.A. , Jeelani S.
Published: February 2008

In this study, sandwich panels were fabricated with neat and nanophased foam cores and three-layered plain weave carbon fabric/SC-15 epoxy-nanoclay composite face sheets. Neat and nanophased foam cores with Nanocor® I-28E nanoclay at a loading of 0.5% and 1% by weight were prepared. Sandwich panels were then fabricated using the co-injection resin transfer molding (CIRTM) process. The face sheets were made by infusing SC-15 epoxy containing 1 and 2% by weight of nanoclay into three layers of plain weave carbon fabric. Samples of size 100 × 100 mm were then cut from the panels and subjected to impact loading using an instrumented impact test setup. Impact response of the samples was recorded and compared. The tested samples were then sectioned into two halves and scanned using a scanner, and optical and scanning electron microscopes to understand the failure patterns. Samples with nanophased foam sustained higher loads and had lower damage areas as compared with neat counterparts. Nanophased foam cores exhibited brittle fracture.
An Examination of Failure Criteria for Notched Orthotropic Ceramic Matrix Composite Laminates
Authors: Yeh Hsien-Yang , Murphy Kyle S. , Yeh Hsien-Liang
Published: February 2008

The purpose of this paper is to further study the Yeh-Stratton (Y-S) failure criterion when applied to the newly developed ceramic matrix composite (CMC). In this study, the failure analysis of notched CMC laminates is investigated by the Y-S criterion and compared to linear elastic stress models including the average stress criterion (ASC), point stress criterion (PSC), and the D criterion.

The materials being examined are fiber-reinforced orthotropic composites, which are a new CMC of interest in the aerospace industry, and a graphite/epoxy AS4/3502. Testing of both fiber-reinforced CMC [0/90] and AS4/3502 [0/902/0] laminates, containing central cracks and under tensile loading conditions, were analytically investigated by the failure criteria and evaluated against the experimental results.

The study results indicate that the Y-S criterion and the linear elastic stress models predict the fracture of orthotropic laminated composites containing a center crack under tensile loading to a similar degree of accuracy. The results also indicate that the damage zone size predicted by the Y-S criterion does not represent the actual damage zone size. The linear elastic stress models appear to predict the actual damage zone size within an order of magnitude. It is apparent that further research on this topic of damage zone size prediction is needed.
Free Vibration of Laminated Composite Circular Arches by Dynamic Stiffness Analysis
Authors: Li Jun  , Hua Hongxing  , Shen Rongying
Published: February 2008

The dynamic stiffness method for studying the vibration characteristics of the laminated composite shallow circular arches is introduced in this article. The exact dynamic stiffness matrix is formulated from the analytical solutions of the governing differential equations of motion of the laminated circular arches, based on second-order shear deformation theory. The application of the present method is illustrated by miscellaneous numerical examples, in which the effects of material orthotropy, the lamination scheme, the curvature ratio, length-to-thickness ratio, and boundary condition upon the natural frequencies of the composite arches are investigated. Compared to those solutions available in the literature, the numerical results demonstrate the accuracy and effectiveness of the present method.
A Study of Taguchi and Design of Experiments Method in Injection Molding Process for Polypropylene Components
Authors: Yang Yung-Kuang , Shie Jie-Ren , Liao Hsin-Te , Wen Jeong-Lian , Yang Rong-Tai
Published: February 2008

This study analyzes contour distortions, wear mass losses and tensile properties of polypropylene (PP) composite components applied to the interior coffer of automobiles. The specimens are prepared under different injection molding conditions by changing melting temperatures, injection speeds, and injection pressures via three computer-controlled progressive strokes. The contour distortions, wear and tensile properties are selected as quality targets. The arrangement of sixteen experiments is based on an orthogonal array table. Both the Taguchi method and the design of experiments (DOE) method are applied to determine an optimal parameter setting. In addition, a side-by-side comparison of two different approaches is provided. In this study, regression models that link the controlled parameters and the targeted outputs are developed, and the mathematic models can be utilized to predict the contour distortions, wear and tensile properties at various injection molding conditions.
Taguchi Approach for Achieving Better Machinability in Unreinforced and Reinforced Polyamides
Authors: Gaitonde V.N. , Karnik S.R. , Mata Francisco , Davim J. Paulo
Published: February 2008

Polyamide composites find wide applications in engineering fields due to favorable properties and hence replaced many traditional metallic materials. In order to increase the properties, the glass fibers are added to unreinforced polyamides. Even though polyamides are produced as near net shapes, machining is required to get the finished products. Thus, the selection of tool and cutting conditions is important in the machining of unreinforced and reinforced polyamides. This article presents the application of Taguchi's quality loss function approach, a multi-response optimization method, for achieving better machinability during turning of both unreinforced polyamide (PA6) and reinforced polyamide with 30% of glass fibers (PA66 GF30). The analysis of means (ANOM) and analysis of variance (ANOVA) on multi-response signal to noise (S/N) ratio are employed to determine the optimal parameter levels and to identify the level of importance of the parameters. The ANOVA results showed that the cutting speed is the most significant factor affecting machinability. Taguchi optimization results suggest that the optimal value of feed rate and cutting speed should be kept at a low level, whereas a polycrystalline diamond (PCD) tool is beneficial over cemented carbide (K10) for machining of both PA6 and PA66 GF30 polyamides to achieve better machinability.
The Properties of Woven Betel Palm (Areca catechu) Reinforced Polyester Composites
Authors: Lai W.L. , Mariatti M.
Published: February 2008

Fibers obtained from the fronds of betel or betel nut ( Areca catechu) palm (or known in Malaysia as pinang tree) were used as woven reinforcement in unsaturated polyester resin. The morphology, physical and mechanical properties of the natural fibers and resulting woven composites were evaluated. Woven betel palm composites were prepared in both untreated and treated forms with different fiber volumes: 3%, 5%, 7%, and 9%. The flexural properties and impact strength of woven betel palm composites improve with the addition of fiber up to 7 vol%. The drop in flexural properties was observed in 9 vol% of fiber due to insufficient resin to wet the fibers during the fabrication of composites. As expected, the treated betel palm fibers display better mechanical properties than those of the untreated system. From the SEM observation, it is found that the alkaline treatment of fibers effectively cleans the fiber surface and increases the fiber surface roughness. In general, mechanical properties of the woven composites made from alkali treated fibers were superior to the untreated fibers.