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A steady torque density increase in the wind industry requires continuous advancement in design and materials. High torque density ratios lead to the use of high-strength nodular cast iron in gearbox parts where until now it has not been necessary to use them. To facilitate the characterization of those materials, taking into account the difficulty of extracting material samples directly from heavy section castings, a dedicated geometry and its manufacturing process are proposed. On the basis of a casting trial, the mechanical property predictions of an EN-GJS-500-14 grade are adjusted following a working methodology that could help to optimise the performance of the different nodular cast iron grades in a high torque density scenario.

In order to ensure casting simulation plausibility, as requested in wind certifications, its default mechanical property prediction is evaluated based on results tested from wind structural castings made in furan no-bake resin systems. Through a standard definition of pre-process parameters and the default post-process provided by commercial software, it is verified that predictions on nodular cast iron are already in order of magnitude with tests on wind castings. To improve the default mechanical property prediction, the specific process of each supplier, an advanced definition of pre-process parameters and new post-process criteria should be considered.

Structural components design in the wind sector is based on international guidelines that in some cases could be ambiguous and excessively conservative. This article reviews the state of the art regarding allowable data of material that must be provided during the different design steps of large structural castings for gearboxes in the wind sector. One of the main issues in designing these components is the presence of relevant stresses in thick-walled sections, where there are sometimes mechanical properties gradients that are forced as result of a specific manufacturing process. At the initial stages of a structural analysis, for either static or fatigue assessment, the concept of allowable material data is established. These material properties could be selected, as a first approach, based on the definition of a relevant thickness in the part, but it forces those properties to be assumed by all sections of the component regardless of their local equivalent thickness and their real local mechanical properties. Other alternatives are possible, such as considering the real properties of the material for each local thickness; this option could be defined on the basis of the geometrical/thermal modulus that are typical concepts of casting process technology. Consequently, this article presents a review of material properties selection in different design codes of the wind sector, as well as available methodologies to provide them.

La diabetes mellitus es uno de los principales problemas de salud a nivel mundial debido a sus altos índices de incidencia, prevalencia, los costes que genera a la economía de cada país, las complicaciones que derivan de esta y los altos índices de mortalidad. Esta enfermedad concierne a la familia, ya que los cambios en el estilo de vida del paciente demandan apoyo familiar, orientación en la toma de decisiones y acciones necesarias para el adecuado manejo de la enfermedad. Asociado a lo anterior, algunos estudios han demostrado los beneficios de un adecuado automanejo en enfermedades crónicas, que implica: adherencia al tratamiento, reconocer síntomas de la enfermedad, hábitos de alimentación saludable, ejercicio y visitas al médico.

Abstract: Objective: A virtual reality tool, called VirSSPA, was developed to optimize the planning of surgical processes. Methods: Segmentation algorithms for Computed Tomography (CT) images: a region growing procedure was used for soft tissues and a thresholding algorithm was implemented to segment bones. The algorithms operate semiautomati- cally since they only need seed selection with the mouse on each tissue segmented by the user. The novelty of the paper is the adaptation of an enhancement method based on histogram thresholding applied to CT images for surgical planning, which simplifies subsequent segmentation. A substantial improvement of the virtual reality tool VirSSPA was obtained with these algorithms. Results: VirSSPA was used to optimize surgical planning, to decrease the time spent on surgical planning and to improve operative results. The success rate increases due to surgeons being able to see the exact extent of the patient’s ailment. This tool can decrease operating room time, thus resulting in reduced costs. Conclusion: Virtual simulation was effective for optimizing surgical planning, which could, consequently, result in improved outcomes with reduced costs.

Muchos estudios han documentado la asociación entre valores bajos de PAPP-A y β-hCG en el suero materno durante el primer trimestre, así como efectos materno-fetales adversos.

Objective:To compare the effects of Mepentol, a hyperoxygenated fatty acid preparation, with a placebo treatment in preventing the development of pressure ulcers.Method:The research study consisted of a multicentre double-blind randomised clinical trial. The incidence of pressure ulcers, relative risk (RR), preventable fraction and number necessary to treat (NNT) were calculated. In addition, Kaplan-Meier survival curves, with log-rank test, and Cox’s proportional hazards regression model were used to compare both groups.Results:A total of 331 patients completed the study: 167 in the control group and 164 in the study group. Pressure-ulcer incidence during the study was 7.32% in the intervention group versus 17.37% in the placebo group (p0.006). These results show that for each 10 patients treated with Mepentol one pressure ulcer was prevented (NNT = 9.95). Survival curves and the regression model showed a significant statistical difference for both groups (p≤0.001). The average cost of Mepentol during the study was ₠7.74.Conclusion:Mepentol is an effective measure for pressure ulcer prevention. It was more effective than a greasy placebo product, and was found to be cost-effective.Declaration of interest:This study was sponsored by Laboratorios Bama-Geve SA, Barcelona, Spain.

The peel strength of oxygen plasma‐treated rubber/polyurethane adhesive joints was measured as a function of the length of the treatment. The trend obtained did not obey the expected mechanisms of adhesion and therefore the precise determination of the locus of failure of the joints was carried out using XPS and infrared attenuated total reflectance (IRATR) spectroscopy. The oxygen plasma treatment for 1 min facilitated the migration of wax to the surface, which was transferred to the adhesive surface during the curing process. The increase in the length of the treatment up to 20 min produced a change in the locus of failure, which is mixed (adhesional in the oxidized rubber layer and cohesional in the wax layer). The oxygen plasma for 40 min produces a damaged oxidized rubber layer, which acts as a weak layer producing a decrease in peel strength and a cohesive failure in that oxidized layer. Copyright © 2000 John Wiley & Sons, Ltd.

The peel strength of oxygen plasma-treated rubber/polyurethane adhesive joints was measured as a function of the length of the treatment. The trend obtained did not obey the expected mechanisms of adhesion and therefore the precise determination of the locus of failure of the joints was carried out using XPS and infrared attenuated total reflectance (IRATR) spectroscopy. The oxygen plasma treatment for 1 min facilitated the migration of wax to the surface, which was transferred to the adhesive surface during the curing process. The increase in the length of the treatment up to 20 min produced a change in the locus of failure, which is mixed (adhesional in the oxidized rubber layer and cohesional in the wax layer). The oxygen plasma for 40 min produces a damaged oxidized rubber layer, which acts as a weak layer producing a decrease in peel strength and a cohesive failure in that oxidized layer. Copyright © 2000 John Wiley & Sons, Ltd.

Vasopressin applied serosally had no effect on electrical parameters and unidirectional Na and Cl fluxes across anin vitro short circuited preparation of lizard ileum. Short circuit current (Isc) and transmural potential difference (PD) across colon were decreased by vasopressin and increased by cyclic AMP. Vasopressin increased the mucosal-to-serosal flux of sodium and chloride across short circuited colon. Cyclic AMP had no effect on the rate of Na absorption but reversed Cl absorption to secretion. Vasopressin enhanced the net absorption of water across the colon but had no effect on absorption across ileum. Cyclic AMP activity in homogenates of colon was not altered by vasopressin but was increased by theophylline. It is concluded that the colonic response of the lizard colon to vasopressin is mediated by a noncyclic AMP mechanism.

The aim of the secondary voltage control is to maintain voltage magnitudes of several load buses, which have been selected as pilot buses, at their optimal values imposed by the tertiary voltage control. In this paper a comprehensive formulation of the secondary voltage control is presented. Centralized control matrices for an optimal proportional integral control are obtained by the minimization of a performance index. Conditions to achieve a stable closed-loop in a decentralized control scheme are stated. A systematic methodology for selecting pilot buses and for dividing the system in decentralized control areas is presented. The differences between centralized and decentralized control schemes are analyzed in a case study based on the New England 39 bus system.