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This paper discusses the use of composite materials in the design process of a horizontal bracing to column connection of an offshore semi-submersible platform to support two wind turbines. The geometry of the connection was optimized to improve the performance and reliability of the connection, columns and bracing tubes. These offshore foundations usually deal with massive structural tubes, and they are used to fit a huge amount of stiffeners. This paper will show how using some horizontal stiffeners combined with their intersection with horizontal bracings tubes, can improve drastically the behavior of the connection. A comparison between conventional materials (steel) and advanced materials (E-glass fibres and epoxy matrix) was performed and it was demonstrated how the use of composite materials makes necessary to modify the connection geometry and configuration to obtain an equivalent performance. This is due to the very different stiffness behavior shown by composites and steel. Therefore, the design of an offshore connection must be approached differently according to the used material. The composite laminate layout design process was also made. The material was evaluated using a Bureau Veritas normative note specifically applicable to composite ship hulls, but adapted to the needs of the materials used in this design, in terms of raw material requirements. The design process of a laminate panel of the connection is shown using the above mentioned standard. All data and results shown here were harvested within the scope of the European research project Fibregy (EU Horizon 2020, Ref. 952966).

The use of multi-scale procedures is encouraged by the continuous increase of computational capacity, but it is still a challenge performing a non-linear analysis of real composite structures without the aid of large computers. This work proposes a strategy to conduct non-linear multi-scale analysis in an efficient way. The proposed method considers that in a large structure, in general, material non-linear processes only take place in a localized region (or in a reduced number of finite elements, if a FE method is used). The strategy determines the elements that require a non-linear analysis defining of a non-linear activation function that accounts for the failure of the most critical point in the microstructure. The procedure conserves the dissipated energy through the scales, being mesh independent as the mesh objectivity concept is extended to the microstructure. The validity of the strategy proposed is proved with the analysis of academic examples showing not only the mesh independency but also the reduction of computational cost. Finally, an industrial composite component is solved using a standard computer, showing that the proposed strategy is capable of reducing the computational cost from 32 days and 14 hours (required by a classical multi-scale method) to less than 12 hours.

Recent case-series of small size implied a pathophysiological association between coronavirus disease 2019 (COVID-19) and severe large-vessel acute ischemic stroke. Given that severe strokes are typically associated with poor prognosis and can be very efficiently treated with recanalization techniques, confirmation of this putative association is urgently warranted in a large representative patient cohort to alert stroke clinicians, and inform pre- and in-hospital acute stroke patient pathways. We pooled all consecutive patients hospitalized with laboratory-confirmed COVID-19 and acute ischemic stroke in 28 sites from 16 countries. To assess whether stroke severity and outcomes (assessed at discharge or at the latest assessment for those patients still hospitalized) in patients with acute ischemic stroke are different between patients with COVID-19 and non-COVID-19, we performed 1:1 propensity score matching analyses of our COVID-19 patients with non-COVID-19 patients registered in the Acute Stroke Registry and Analysis of Lausanne Registry between 2003 and 2019. Between January 27, 2020, and May 19, 2020, 174 patients (median age 71.2 years; 37.9% females) with COVID-19 and acute ischemic stroke were hospitalized (median of 12 patients per site). The median National Institutes of Health Stroke Scale was 10 (interquartile range [IQR], 4-18). In the 1:1 matched sample of 336 patients with COVID-19 and non-COVID-19, the median National Institutes of Health Stroke Scale was higher in patients with COVID-19 (10 [IQR, 4-18] versus 6 [IQR, 3-14]), P=0.03; (odds ratio, 1.69 [95% CI, 1.08-2.65] for higher National Institutes of Health Stroke Scale score). There were 48 (27.6%) deaths, of which 22 were attributed to COVID-19 and 26 to stroke. Among 96 survivors with available information about disability status, 49 (51%) had severe disability at discharge. In the propensity score-matched population (n=330), patients with COVID-19 had higher risk for severe disability (median mRS 4 [IQR, 2-6] versus 2 [IQR, 1-4], P

WOS: 000434263000007, PubMed: 29766772, BACKGROUND Embolic strokes of undetermined source represent 20% of ischemic strokes and are associated with a high rate of recurrence. Anticoagulant treatment with rivaroxaban, an oral factor Xa inhibitor, may result in a lower risk of recurrent stroke than aspirin. METHODS We compared the efficacy and safety of rivaroxaban (at a daily dose of 15 mg) with aspirin (at a daily dose of 100 mg) for the prevention of recurrent stroke in patients with recent ischemic stroke that was presumed to be from cerebral embolism but without arterial stenosis, lacune, or an identified cardioembolic source. The primary efficacy outcome was the first recurrence of ischemic or hemorrhagic stroke or systemic embolism in a time-to-event analysis; the primary safety outcome was the rate of major bleeding. RESULTS A total of 7213 participants were enrolled at 459 sites; 3609 patients were randomly assigned to receive rivaroxaban and 3604 to receive aspirin. Patients had been followed for a median of 11 months when the trial was terminated early because of a lack of benefit with regard to stroke risk and because of bleeding associated with rivaroxaban. The primary efficacy outcome occurred in 172 patients in the rivaroxaban group (annualized rate, 5.1%) and in 160 in the aspirin group (annualized rate, 4.8%) (hazard ratio, 1.07; 95% confidence interval [CI], 0.87 to 1.33; P=0.52). Recurrent ischemic stroke occurred in 158 patients in the rivaroxaban group (annualized rate, 4.7%) and in 156 in the aspirin group (annualized rate, 4.7%). Major bleeding occurred in 62 patients in the rivaroxaban group (annualized rate, 1.8%) and in 23 in the aspirin group (annualized rate, 0.7%) (hazard ratio, 2.72; 95% CI, 1.68 to 4.39; P, BayerBayer AG; Janssen Research and Development, Supported by Bayer and Janssen Research and Development.

Most of the existing materials around us can be considered composite materials, since they are composed by several phases or components at certain spatial scale. The physical and chemical properties of composites, as occurs with structures composed by two or more materials, is defined by the response provided by their constituents. Therefore, a good characterization of the composite requires considering the performance of its components. In the last decades, several methods have been proposed with this approach to characterize composite materials, most of them based on multiscale techniques. Nowadays, multiscale homogenization analysis is a popular topic in the simulation of composite materials. This is because the complexity of new composites demands of advanced analysis techniques for their correct characterization, and thanks to the continuous increase of computational capacity. However, the computational cost when multiscale procedures are taken to the non-linear range and are applied to real-size structures is still excessively high. In this context, this monograph presents a comprehensive homogenization formulation for an efficient non-linear multiscale modeling of composite structures. The development of a composite multiscale constitutive model is addressed from two different homogenization approaches. The first one corresponds to a phenomenological homogenization procedure for the non-linear analysis of carbon nanotubes reinforced composites. The second one is a general two-scale homogenization procedure to analyze three-dimensional composite structures. Carbon nanotubes (CNTs) have been regarded as ideal reinforcements for high-performance composites. The formulation developed takes into account explicitly the performance of the interface between the matrix and the CNTs. The load is transferred to the nanotubes through the considered interface. The composite non-linear behavior results from the non-linearities of its constituents, and in case of interface damage, it also becomes non-linear the law defined to couple the interface with the CNTs. The formulation is validated studying the elastic response and non-linear behavior of several composites. In the context of multiscale homogenization, a first-order and an enhanced-first-order formulation is developed. The results obtained for laminate composites using the first-order formulation are compared with other microscopic formulations, showing that the homogenization method is an excellent alternative when microstructural effects must be taken into account. Then, a strategy to conduct non-linear multiscale analysis in an efficient way is proposed. The procedure conserves the dissipated energy through the scales and is mesh independence. The analysis of academic examples is used to show the capacity of the non-linear strategy. Finally, the simulation of an industrial composite component proves the performance and benefits of the non-linear homogenization procedure developed.

The mechanical response of IM7-8552 carbon epoxy was investigated for transverse tension and transverse tension/in-plane shear loadings at static and dynamic strain rates using transverse tension and off-axis tension specimens. The dynamic tests were carried out on a split-Hopkinson tension bar at axial strain rates from 113 to 300 s−1. With the already available off-axis and transverse compression test data for IM7-8552, a comprehensive data set is available now, which can be used for validation and calibration of numerical models. The measured axial stress-strain response was simulated using a fully 3D transversely isotropic elastic-viscoplastic constitutive model. The constitutive model represents a viscoplastic extension of the transversely-isotropic plasticity model developed by the authors (Vogler et al. in Mech Mater 59:50-64, 2013). An invariant based failure criterion is added to the model to be able to predict the strength for a given orientation and strain rate accurately. The strain rate dependency of the elastic and ultimate strength properties is introduced in the model through scaling functions. A good correlation between the measured and numerically predicted stress-strain response and failure of the specimens was achieved for all specimen types and both strain rate regimes.

Since 1st light in 2002, HARPS has been setting the standard in the exo-planet detection by radial velocity (RV) measurements[1]. Based on this experience, our consortium is developing a high accuracy near-infrared RV spectrograph covering YJH bands to detect and characterize low-mass planets in the habitable zone of M dwarfs. It will allow RV measurements at the 1-m/s level and will look for habitable planets around M- type stars by following up the candidates found by the upcoming space missions TESS, CHEOPS and later PLATO. NIRPS and HARPS, working simultaneously on the ESO 3.6m are bound to become a single powerful high-resolution, high-fidelity spectrograph covering from 0.4 to 1.8 micron. NIRPS will complement HARPS in validating earth-like planets found around G and K-type stars whose signal is at the same order of magnitude than the stellar noise. Because at equal resolving power the overall dimensions of a spectrograph vary linearly with the input beam etendue, spectrograph designed for seeing-limited observations are large and expensive. NIRPS will use a high order adaptive optics system to couple the starlight into a fiber corresponding to 0.4” on the sky as efficiently or better than HARPS or ESPRESSO couple the light 0.9” fiber. This allows the spectrograph to be very compact, more thermally stable and less costly. Using a custom tan(θ)=4 dispersion grating in combination with a start-of-the-art Hawaii4RG detector makes NIRPS very efficient with complete coverage of the YJH bands at 110’000 resolution. NIRPS works in a regime that is in-between the usual multi-mode (MM) where 1000’s of modes propagates in the fiber and the single mode well suited for perfect optical systems. This regime called few-modes regime is prone to modal noise- Results from a significant R and D effort made to characterize and circumvent the modal noise show that this contribution to the performance budget shall not preclude the RV performance to be achieved.

Editors: Amanda Harris.

Objective: To update the Spanish Society of Neurology's guidelines for subarachnoid haemorrhage diagnosis and treatment. Material and methods: A review and analysis of the existing literature. Recommendations are given based on the level of evidence for each study reviewed. Results: The most common cause of spontaneous subarachnoid haemorrhage (SAN) is cerebral aneurysm rupture. Its estimated incidence in Spain is 9/100 000 inhabitants/year with a relative frequency of approximately 5% of all strokes. Hypertension and smoking are the main risk factors. Stroke patients require treatment in a specialised centre. Admission to a stroke unit should be considered for SAH patients whose initial clinical condition is good (Grades I or II on the Hunt and Hess scale). We recommend early exclusion of aneurysms from the circulation. The diagnostic study of choice for SAH is brain CT (computed tomography) without contrast. If the test is negative and SAH is still suspected, a lumbar puncture should then be performed. The diagnostic tests recommended in order to determine the source of the haemorrhage are MRI (magnetic resonance imaging) and angiography. Doppler ultrasonography studies are very useful for diagnosing and monitoring vasospasm. Nimodipine is recommended for preventing delayed cerebral ischaemia. Blood pressure treatment and neurovascular intervention may be considered in treating refractory vasospasm. Conclusions: SAH is a severe and complex disease which must be managed in specialised centres by professionals with ample experience in relevant diagnostic and therapeutic processes. (C) 2012 Sociedad Espanola de Neurologia. Published by Elsevier Espana, S.L. All rights reserved.

Objective: To update the Spanish Society of Neurology's guidelines for subarachnoid haemorrhage diagnosis and treatment. Material and methods: A review and analysis of the existing literature. Recommendations are given based on the level of evidence for each study reviewed. Results: The most common cause of spontaneous subarachnoid haemorrhage (SAN) is cerebral aneurysm rupture. Its estimated incidence in Spain is 9/100 000 inhabitants/year with a relative frequency of approximately 5% of all strokes. Hypertension and smoking are the main risk factors. Stroke patients require treatment in a specialised centre. Admission to a stroke unit should be considered for SAH patients whose initial clinical condition is good (Grades I or II on the Hunt and Hess scale). We recommend early exclusion of aneurysms from the circulation. The diagnostic study of choice for SAH is brain CT (computed tomography) without contrast. If the test is negative and SAH is still suspected, a lumbar puncture should then be performed. The diagnostic tests recommended in order to determine the source of the haemorrhage are MRI (magnetic resonance imaging) and angiography. Doppler ultrasonography studies are very useful for diagnosing and monitoring vasospasm. Nimodipine is recommended for preventing delayed cerebral ischaemia. Blood pressure treatment and neurovascular intervention may be considered in treating refractory vasospasm. Conclusions: SAH is a severe and complex disease which must be managed in specialised centres by professionals with ample experience in relevant diagnostic and therapeutic processes. (C) 2012 Sociedad Espanola de Neurologia. Published by Elsevier Espana, S.L. All rights reserved.

El objetivo de estudio fue analizar la metodología de enseñanza de los deportes de invasión en Educación Primaria. Para ello, se validó y diseñó un cuestionario con las siguientes dimensiones: cuantificación de la programación sobre deportes invasión y disciplinas impartidas, metodología horizontal o vertical, situaciones de aprendizaje utilizadas y creencias metodológicas. El cuestionario fue respondido por 151 maestros de Educación Física de Sevilla. Los resultados reflejan que los maestros dedican una gran cantidad de su programación a los deportes de invasión. Baloncesto, fútbol y balonmano son las disciplinas más impartidas. Los maestros de Educación Física utilizan mayormente una metodología vertical. Las situaciones de aprendizaje de igualdad numérica son las más utilizadas para enseñar deportes invasión. Por último, las creencias metodológicas de los maestros se orientan hacia un aprendizaje activo. The aim of this study was to analyze teaching methodology in invasion games in Primary Education. For this purpose, a questionnaire with the following parameters was drawn up and validated: Quantification of the programs involving invasion games and disciplines taught, horizontal or vertical methodologies, learning situations and learning situations and methodological approaches used. The questionnaire was answered by 151 physical education teachers in Seville. The results show that teachers the teachers devote a large proportion of their teaching programs to invasion games. Basketball, football and handball are the most taught. A vertical approach is generally applied by physical education teachers. Learning situations of numerical equality are the most used for the teaching of invasion games. Finally, the methodological approaches of the teachers are focused on active learning.

El objetivo de estudio fue analizar la metodología de enseñanza de los deportes de invasión en Educación Primaria. Para ello, se validó y diseñó un cuestionario con las siguientes dimensiones: cuantificación de la programación sobre deportes invasión y disciplinas impartidas, metodología horizontal o vertical, situaciones de aprendizaje utilizadas y creencias metodológicas. El cuestionario fue respondido por 151 maestros de Educación Física de Sevilla. Los resultados reflejan que los maestros dedican una gran cantidad de su programación a los deportes de invasión. Baloncesto, fútbol y balonmano son las disciplinas más impartidas. Los maestros de Educación Física utilizan mayormente una metodología vertical. Las situaciones de aprendizaje de igualdad numérica son las más utilizadas para enseñar deportes invasión. Por último, las creencias metodológicas de los maestros se orientan hacia un aprendizaje activo., The aim of this study was to analyze teaching methodology in invasion games in Primary Education. For this purpose, a questionnaire with the following parameters was drawn up and validated: Quantification of the programs involving invasion games and disciplines taught, horizontal or vertical methodologies, learning situations and learning situations and methodological approaches used. The questionnaire was answered by 151 physical education teachers in Seville. The results show that teachers the teachers devote a large proportion of their teaching programs to invasion games. Basketball, football and handball are the most taught. A vertical approach is generally applied by physical education teachers. Learning situations of numerical equality are the most used for the teaching of invasion games. Finally, the methodological approaches of the teachers are focused on active learning.

El objetivo de estudio fue analizar la metodología de enseñanza de los deportes de invasión en Educación Primaria. Para ello, se validó y diseñó un cuestionario con las siguientes dimensiones: cuantificación de la programación sobre deportes invasión y disciplinas impartidas, metodología horizontal o vertical, situaciones de aprendizaje utilizadas y creencias metodológicas. El cuestionario fue respondido por 151 maestros de Educación Física de Sevilla. Los resultados reflejan que los maestros dedican una gran cantidad de su programación a los deportes de invasión. Baloncesto, fútbol y balonmano son las disciplinas más impartidas. Los maestros de Educación Física utilizan mayormente una metodología vertical. Las situaciones de aprendizaje de igualdad numérica son las más utilizadas para enseñar deportes invasión. Por último, las creencias metodológicas de los maestros se orientan hacia un aprendizaje activo., The aim of this study was to analyze teaching methodology in invasion games in Primary Education. For this purpose, a questionnaire with the following parameters was drawn up and validated: Quantification of the programs involving invasion games and disciplines taught, horizontal or vertical methodologies, learning situations and learning situations and methodological approaches used. The questionnaire was answered by 151 physical education teachers in Seville. The results show that teachers the teachers devote a large proportion of their teaching programs to invasion games. Basketball, football and handball are the most taught. A vertical approach is generally applied by physical education teachers. Learning situations of numerical equality are the most used for the teaching of invasion games. Finally, the methodological approaches of the teachers are focused on active learning.

El objetivo de estudio fue analizar la metodología de enseñanza de los deportes de invasión en Educación Primaria. Para ello, se validó y diseñó un cuestionario con las siguientes dimensiones: cuantificación de la programación sobre deportes invasión y disciplinas impartidas, metodología horizontal o vertical, situaciones de aprendizaje utilizadas y creencias metodológicas. El cuestionario fue respondido por 151 maestros de Educación Física de Sevilla. Los resultados reflejan que los maestros dedican una gran cantidad de su programación a los deportes de invasión. Baloncesto, fútbol y balonmano son las disciplinas más impartidas. Los maestros de Educación Física utilizan mayormente una metodología vertical. Las situaciones de aprendizaje de igualdad numérica son las más utilizadas para enseñar deportes invasión. Por último, las creencias metodológicas de los maestros se orientan hacia un aprendizaje activo. The aim of this study was to analyze teaching methodology in invasion games in Primary Education. For this purpose, a questionnaire with the following parameters was drawn up and validated: Quantification of the programs involving invasion games and disciplines taught, horizontal or vertical methodologies, learning situations and learning situations and methodological approaches used. The questionnaire was answered by 151 physical education teachers in Seville. The results show that teachers the teachers devote a large proportion of their teaching programs to invasion games. Basketball, football and handball are the most taught. A vertical approach is generally applied by physical education teachers. Learning situations of numerical equality are the most used for the teaching of invasion games. Finally, the methodological approaches of the teachers are focused on active learning.

Introduction: Update of Acute Ischaemic Stroke Treatment Guidelines of the Spanish Neurological Society based on a critical review of the literature. Recommendations are made based on levels of evidence from published data and studies. Development: Organized systems of care should be implemented to ensure access to the optimal management of all acute stroke patients in stroke units. Standard of care should include treatment of blood pressure (should only be treated if values are over 185/105 mmHg), treatment of hyperglycaemia over 155 mg/dl, and treatment of body temperature with antipyretic drugs if it rises above 37.5 degrees C. Neurological and systemic complications must be prevented and promptly treated. Decompressive hemicraniectomy should be considered in cases of malignant cerebral oedema. Intravenous thrombolysis with rtPA should be administered within 4.5 hours from symptom onset, except when there are contraindications. Intra-arterial pharmacological thrombolysis can be considered within 6 hours, and mechanical thrombectomy within 8 hours from onset, for anterior circulation strokes, while a wider window of opportunity up to 12-24 hours is feasible for posterior strokes. There is not enough evidence to recommend routine use of the so called neuroprotective drugs. Anticoagulation should be administered to patients with cerebral vein thrombosis. Rehabilitation should be started as early as possible. Conclusion: Treatment of acute ischaemic stroke includes management of patients in stroke units. Systemic thrombolysis should be considered within 4.5 hours from symptom onset. Intraarterial approaches with a wider window of opportunity can be an option in certain cases. Protective and restorative therapies are being investigated (C) 2011 Sociedad Espanola de Neurologia. Published by Elsevier Espana, S.L. All rights reserved.

Introduction: Update of Acute Ischaemic Stroke Treatment Guidelines of the Spanish Neurological Society based on a critical review of the literature. Recommendations are made based on levels of evidence from published data and studies. Development: Organized systems of care should be implemented to ensure access to the optimal management of all acute stroke patients in stroke units. Standard of care should include treatment of blood pressure (should only be treated if values are over 185/105 mmHg), treatment of hyperglycaemia over 155 mg/dl, and treatment of body temperature with antipyretic drugs if it rises above 37.5 degrees C. Neurological and systemic complications must be prevented and promptly treated. Decompressive hemicraniectomy should be considered in cases of malignant cerebral oedema. Intravenous thrombolysis with rtPA should be administered within 4.5 hours from symptom onset, except when there are contraindications. Intra-arterial pharmacological thrombolysis can be considered within 6 hours, and mechanical thrombectomy within 8 hours from onset, for anterior circulation strokes, while a wider window of opportunity up to 12-24 hours is feasible for posterior strokes. There is not enough evidence to recommend routine use of the so called neuroprotective drugs. Anticoagulation should be administered to patients with cerebral vein thrombosis. Rehabilitation should be started as early as possible. Conclusion: Treatment of acute ischaemic stroke includes management of patients in stroke units. Systemic thrombolysis should be considered within 4.5 hours from symptom onset. Intraarterial approaches with a wider window of opportunity can be an option in certain cases. Protective and restorative therapies are being investigated (C) 2011 Sociedad Espanola de Neurologia. Published by Elsevier Espana, S.L. All rights reserved.

Background and Objective: To update the ad hoc Committee of the Cerebrovascular Diseases Study Group of The Spanish Neurological Society guidelines on prevention of ischaemic stroke (IS) and Transient Ischaemic Attack (TIA). Methods: We reviewed the available evidence on ischaemic stroke and TIA prevention according to aetiological subtype. Levels of evidence and recommendation levels are based on the classification of the Centre for Evidence-Based Medicine. Results: In atherothrombotic IS, antiplatelet therapy and revascularization procedures in selected cases of ipsilateral carotid stenosis (70%-90%) reduce the risk of recurrences. In cardioembolic IS (atrial fibrillation, valvular diseases, prosthetic valves and myocardial infarction with mural thrombus) prevention is based on the use of oral anticoagulants. Preventive therapies for uncommon causes of IS will depend on the aetiology. In the case of cerebral venous thrombosis oral anticoagulation is effective. Conclusions: We conclude with recommendations for clinical practice in prevention of IS according to the aetiological subtype presented by the patient. (c) 2011 Sociedad Espanola de Neurologia. Published by Elsevier Espana, S.L. All rights reserved.

Objetivo: La tiaprida es una benzamida sustituida clasificada como neuroléptica atípica. Ante la ausencia de datos publicados sobre su estabilidad en disolución para administración en perfusión continua intravenosa, este estudio analiza la estabilidad de la tiaprida en diferentes soluciones para infusión intravenosa, a diferentes concentraciones y durante 48 horas. Método: Se prepararon muestras de tiaprida por triplicado en cloruro sódico al 0,9% y en glucosa al 5% a concentraciones de 1 y 2 mg/mL. Estas muestras se conservaron en recipientes de cristal sin fotoprotección, a temperatura ambiente (25 ± 2ºC). Los tiempos de muestreo a las 0, 1, 3, 6, 12, 24 y 48 horas incluyeron inspección visual y determinación del pH. Se cuantificó la concentración de tiaprida en las muestras mediante cromatografía líquida de alta eficacia acoplada a espectrometría de masas. A los valores de concentración a tiempo 0 se les asignó el valor de referencia del 100%. Se consideraron estables aquellas muestras con concentración de tiaprida superior al 90% de la inicial. Resultados: No se observaron cambios visibles en las muestras analizadas. El valor del pH varió en un rango de entre 0,1 y 0,4 unidades. A las 48 horas, la concentración remanente en cloruro sódico a 1 y 2 mg/mL fue 93,8% y 91,6%, respectivamente. En glucosa al 5%, a 1 y 2 mg/mL fue 96,8% y 94,1%, respectivamente. Conclusión: Las disoluciones de tiaprida en cloruro sódico al 0,9% y en glucosa al 5%, a concentraciones de 1 y 2 mg/mL, en recipientes de cristal sin fotoprotección, a temperatura ambiente, son estables física y químicamente durante 48 horas. Objectives: Tiapride is a substituted benzamide classified as an atypical neuroleptic. To our knowledge, there are no published data on its stability prepared as a continuous intravenous infusion. The current study analysed its stability in two different infusion solutions and concentrations over 48 hours. Method: Triplicate samples of tiapride were prepared in 0.9% sodium chloride and in 5% dextrose solutions at final concentrations of 1 and 2 mg/ml. Samples were collected in glass bottles without photoprotection and at room temperature (25 ± 2ºC). Sampling times at 0, 1, 3, 6, 12, 24 and 48 hours included a visual inspection for colour changes and appearance of precipitation as well as pH determination. Tiapride was quantified at selected times by mass spectrometry using high-performance liquid chro-matography. Concentration values in the samples corresponding to 0 hours were given a reference value of 100%. Concentrations in subsequent samples greater than 90% were considered stable. Results: No colour change or precipitation was observed during the study period. pH values ranged between 0.1 and 0.4 units. At 48 hours, the concentration of remaining tiapride in sodium chloride 1 mg/ml and 2 mg/ml was 93.8% and 91.6%, respectively. That in 5% dextrose 1 mg/ml and 2 mg/ml was 96.8% and 94.1%, respectively. Conclusion: Dilutions of tiapride in 0.9% sodium chloride and in 5% dextrose solution, at concentrations of 1 mg/ml and 2 mg/ml, in glass bottles and at room temperature were stable both physically and chemically during 48 hours.

Intracerebral haemorrhage accounts for 10%-15% of all strokes; however it has a poor prognisis with higher rates of morbidity and mortality. Neurological deterioration is often observed during the first hours after onset and determines poor prognosis. Intracerebral. haemorrhage, therefore, is a neurological emergency which must be diagnosed and treated properly as soon as possible. In this guide we review the diagnostic procedures and factors that influence the prognosis of patients with intracerebral haemorrhage and we establish recommendations for the therapeutic strategy, systematic diagnosis, acute treatment and secondary prevention for this condition. (C) 2011 Sociedad Espanola de Neurologia. Published by Elsevier Espana, S.L. All rights reserved.

Objective: To update the ad hoc Committee of the Cerebrovascular Diseases Study Group of The Spanish Neurological Society guidelines on prevention of ischaemic stroke (IS) and transient ischaemic attack (TIA). Methods: We reviewed available evidence on risk factors and means of modifying them to prevent ischaemic stroke and TIA. Levels of evidence and recommendation grades are based on the classification of the Centre for Evidence-Based Medicine. Results: This first section summarises the recommendations for action on the following factors: blood pressure, diabetes, lipids, tobacco and alcohol consumption, diet and physical activity, cardio-embolic diseases, asymptomatic carotid stenosis, hormone replacement therapy and contraceptives, hyperhomocysteinemia, prothrombotic states and sleep apnea syndrome. Conclusions: Changes in lifestyle and pharmacological treatment for hypertension, diabetes mellitus and dyslipidemia, according to criteria of primary and secondary prevention, are recommended for preventing ischemic stroke. (C) 2011 Sociedad Espanola de Neurologia. Published by Elsevier Espana, S.L. All rights reserved.

Since their discovery by Lijima in 1991[1], carbon nanotubes (CNTs), are considered a new generation of reinforcement [2]. Their "nano" size structure makes them potentially free of defects, which provides them with excellent physical properties [3,4]. There are two main nanotube types: single wall nanotubes (SWNT) and multi wall nanotubes (MWNT). These last ones consist in several concentric walls, one inside the other. In a composite, one the most important factors that condition their mechanical performance is the interfacial tension between matrix and reinforcement. In general, the loads in a composite structure are introduced to the matrix and then are transferred to the reinforcement through the interface [5]. Therefore, the interface can be defined as the region, surrounding the reinforcement, where this stress transfer takes place. The properties of the composite depend on the properties of this region and its ability to transfer the load efficiently. This work proposes a new formulation to predict the mechanical properties and mechanical behaviour of nanotube-reinforced composites. The formulation is based on the mixing theory [6]. It obtains the behaviour of the composite from the mechanical performance of its constitutive materials: matrix, carbon-nanotube and the interface that bonds both of them.

Intracranial stenoses (IS) are known to be a manifestation of atherosclerosis and a cause of cerebral ischemia, although very few clinical reports have appeared describing such patients in our milieu.The aim of this study was to describe the vascular risk factors, clinical presentation, radiological characteristics, aetiological role played in strokes and the vessels affected in a series of Spanish patients suffering from stroke and IS.We conducted a retrospective descriptive study of patients admitted to the Cerebrovascular Pathology Unit with strokes and IS between 1990 and 2001. Data collected included: age, sex, arterial hypertension (AHT), diabetes (Db), hypercholesterolemia (HC), smoking (Sm), ischemic or emboligenic heart disease, intermittent claudication, carotid atheromatosis, clinical presentation of stroke and earlier lesions in computerised axial tomography (CAT) scans of the brain.132 patients; 187 stenotic vessels: 65.7% males, mean age 68.3 years. AHT 65%, Db 39%, HC 40%, Sm 43%, ischemic heart disease 22%, emboligenic heart disease 17%, intermittent claudication 13%.TIA 16%, LACI 33%; PACI 25%, TACI 4%, POCI 19%. Significant carotid atheromatosis 26.5%. Symptomatic IS 50%: mean age 63.3 years, 64% females. Arteries affected: vertebral (VA) 28%; middle cerebral (MCA) 27%; carotid siphon 21%; basilar (BA) 10% (65% symptomatic); anterior cerebral (ACA) 5% and posterior cerebral (CPA) 4%. Normal cranial CAT scan 24%, lacunar infarcts 42%, territorial 32%; leukoaraiosis 17%.Patients with stroke and IS display different clinical profiles according to their sex (males: a higher number of vascular risk factors and clinical involvement of other territories; females are more symptomatic, AHT and HC); they usually present clinically as lacunar syndromes, with a scarce amount of significant atheromatous carotid involvement, except IS of the VA, and IS of the BA are the most symptomatic.

This article presents the current status of the use of Artificial Neural Networks (ANNs) in process engineering applications where common mathematical methods do not completely represent the behavior shown by experimental observations, results, and plant operating data. Three examples of the use of ANNs in typical process engineering applications such as prediction of activity in solvent-polymer binary systems, prediction of a surfactant self-diffusion coefficient of micellar systems, and process control and simulation are shown. These examples are important for polymerization applications, enhanced-oil recovery, and automatic process control. El presente artículo presenta el estado actual de la utilización de las Redes Neuronales Artificiales (ANNs) en aplicaciones de ingeniería de procesos donde los métodos matemáticos tradicionales no muestran completamente el comportamiento representado por observaciones y resultados experimentales o datos de operación de plantas. Este artículo muestra tres ejemplos de la utilización de ANNs en aplicaciones típicas de ingeniería de proceso como son la predicción de coeficientes de actividad en sistemas binarios solvente-polímero, predicción de coeficientes de difusión de un surfactante en sistemas micelares y control y simulación de procesos. Estas aplicaciones son importantes en el área de polimerización, recuperación mejorada de crudo y control automático de procesos.

Fuel oil is a refinery by-product with a big economical effect due to its high production volumen, diluent use and market specifications based on low viscosity and low sulfur content. When these specifications are not achieved or they are not steady during the process, additional costs are generated by reprocessing, recirculation, storage, laboratory analysis, pumping, etc.. An in-line viscosity automatic control, previously evaluated in a pilot plant, was installed in order to optimize the fuel oil preparation system. This type of control minimizes viscosity variation, maintains the product specifications and allows a proper dosage of diluent. The viscosity automatic control system has added several benefits as follows: decreases the diluent volumen per day, decreases length of final products preparation, fewer number of samples to analyze, a more steady operation of plant, less sedimentation in storage tanks and mass and heat transfer processes more efficient. El combustóleo, debido a las especificaciones exigidas, de bajo azufre y baja viscosidad, es un subproducto de la refinación, de gran influencia económica por su alto volumen de producción, su alto consumo de diluyente y las restricciones de mercadeo. Si las especificaciones finales no son alcanzadas en el proceso, o son variables con el tiempo, se generan costos adicionales para alcanzar la calidad final requerida. La instalación del sistema de control automático de la viscosidad en línea del combustóleo, previamente evaluado a escala piloto, ha facilitado y optimizado su preparación, minimizando la variación de la viscosidad, dosificando un volumen adecuado de diluyente, que es monitoreado desde un sistema de control distribuido. Anteriormente, se dificultaba mantener la estabilidad del producto, por la gran gama de factores que afectan la relación óptima de corrientes constituyentes del producto. Algunos de los efectos alcanzados con este sistema de control son: disminución promedio día de volumen de diluyente, disminución de los tiempos de preparación de productos finales, menor número de muestras de control al laboratorio, más estabilidad en la operación de la planta, menor sedimentación en zonas de almacenamiento, y mayor eficiencia en procesos de transferencia de masa y calor.

It has been postulated that serotonin may play a more important role in hypertension in the elderly than in younger patients (Hansson & Hedner 1986). Ketanserin is predominantly an S2-serotonergic antagonist that inhibits serotonin-induced vasoconstriction and platelet aggregation in patients with arterial hypertension and other cardiovascular diseases such as peripheral arterial obstructive pathology (De Cree et al. 1985a). Furthermore, ketanserin seems to be more effective in elderly hypertensive patients than in younger patients. This age-related antihypertensive effect could be compatible with some serotonergic component which is more manifest in older patients (De Cree et al. 1985b). The earliest apparent haemodynamic abnormality in hypertension, aside from increased total peripheral resistance, is related to a decreased left ventricular diastolic function (Inouye et al. 1984). Ketanserin does not appear to alter this important determinant of cardiac function at rest when evaluated in a 2-month treatment period (Sanchez et al. 1986a). The aim of the present study was to evaluate the effects of ketanserin in elderly hypertensives during I year's treatment, with special emphasis on left ventricular function. 1. Methods

The hemodynamic effects of a new drug: molsidomine (M) were evaluated in 9 patients with congestive myocardiopathy. To that end, with a 4-channel Swan-Ganz catheter and cardiac output computer, the following hemodynamic parameters were measured in the control condition (CC) and 5, 15 and 30 minutes after sublingual administration of 4 mg of M: heart rate (HR), systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), cardiac index (CI), stroke volume index (SVI), systemic vascular resistance (SVR), pulmonary vascular resistance (PVR) and the stroke work index (SWI). Comparing the data in CC and at the end of the study, we found a decrease of 80 +/- 5 to 76 +/- 5 b/m (p less than 0.01) in HR, of 91 +/- 4 to 84 +/- 4 mmHg (p less than 0.01) in MAP and of 3087 +/- 151 to 2758 +/- 131 d/c/s-5 in SVR (p less than 0.02); a drop in PWP of 27 +/- 3 to 20 +/- 3 mmHg (p less than 0.001) and in PVR of 1367 +/- 293 to 1115 +/- 256 d/c/s-5 (p less than 0.001); an increase in SVI of 31 +/- 3 to 34 +/- 2 ml/b/m2 (p less than 0.05) and non-significant changes in CI of 2380 +/- 96 to 2459 +/- 82 ml/m2 (p less than 0.03) and in the SWI of 34 +/- 4 to 37 +/- 4 gm/m2 (p less than 0.1). We conclude that in patients with severe heart failure, the fundamental effects of M appears to be vasodilation in both pulmonary and systemic circulations demonstrated by a fall in PWP, PVR, MAP and SVR together with a mild increase in SVI without significant changes in CI and SWI.

The appearance of transient ischemic attacks (TIA) is an important sign of vascular risk. The maximum time the deficit lasts has been set arbitrarily at 24 hours. It is assumed that TIA does not entail permanent vascular lesions.A retrospective review of the clinical records of patients diagnosed as suffering from TIA in our centre between 1996 and 1997. Analysis of associated risk factors (RF), duration and findings in neuroimaging.The clinical records of 173 patients (106 males) were examined. The RF identified were similar to those described for ischemic strokes. 45.6% of patients with a history of vascular pathologies received no preventative treatment. 58% of the TIA were resolved within the first 30 minutes and 71% within the first hour. Cranial CT was normal in 69%, showed old lesions in 26% and lesions that were compatible with the clinical signs of TIA in 5% (in the latter case the duration of the episodes was greater).TIA shares the same RF and aetiopathogenic mechanisms as ischemic stroke and should, therefore, be considered as such. There is a need to revise the concept of TIA paying special attention to the findings of neuroimaging or to establish duration limits that are better matched to the practical reality. TIA maintains a practical interest since it provides a simple method of identifying patients with a high vascular risk.

Stroke is the main cause of admission to Neurology departments and cardioembolic stroke (CS) is one of the most common subtypes of stroke.A multicentre prospective observational study was performed in 5 Neurology departments in public hospitals in the Region of Madrid (Spain). The objective was to estimate the use of healthcare resources and costs of acute CS management. Patients with acute CS at48h from onset were recruited. Patients' socio-demographic, clinical, and healthcare resource use data were collected during hospitalisation and at discharge up to 30 days after admission, including data for rehabilitation treatment after discharge.During an 8-month recruitment period, 128 patients were recruited: mean age, 75.3±11.25; 46.9% women; mortality rate, 4.7%. All patients met the CS diagnostic criteria established by GEENCV-SEN, based on medical history or diagnostic tests. Fifty per cent of the patients had a history of atrial fibrillation and 18.8% presented other major cardioembolic sources. Non-valvular atrial fibrillation was the most frequent cause of CS (33.6%). Data for healthcare resource use, given a mean total hospital stay of 10.3±9.3 days, are as follows: rehabilitation therapy during hospital stay (46.9%, mean 4.5 days) and after discharge (56.3%, mean 26.8 days), complications (32%), specific interventions (19.5%), and laboratory and diagnostic tests (100%). Head CT (98.4%), duplex ultrasound of supra-aortic trunks (87.5%), and electrocardiogram (85.9%) were the most frequently performed diagnostic procedures. Average total cost per patient during acute-phase management and rehabilitation was €13,139. Hospital stay (45.0%) and rehabilitation at discharge (29.2%) accounted for the largest part of resources used.Acute CS management in the Region of Madrid resulted consumes large amounts of resources (€13,139), mainly due to hospital stays and rehabilitation.