A large displacement structural analysis of a pipeline subjected to gravity and bouyancy forces

p. 489-508A nonlinear analysis of an elastic tube subjected to gravity forces and buoyancy pressure is carried out. An update lagrangian formulation is used. The structural analysis efficiency in terms of computer time and accuracy, has been improved when load stiffness matrices have been introduced. In this way the follower forces characteristics such as their intensity and direction changes can be well represented. A sensitivity study of different involved variables on the final deformed pipeline shape is carried out.Mosquera, JC.; Garcia-Palacios, J.; Samartin, A. (2009). A large displacement structural analysis of a pipeline subjected to gravity and bouyancy forces. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/654

Optimal boundary geometry in an elasticity problem: a systematic adjoint approach

p. 509-524In different problems of Elasticity the definition of the optimal geometry of the boundary, according to a given objective function, is an issue of great interest. Finding the shape of a hole in the middle of a plate subjected to an arbitrary loading such that the stresses along the hole minimizes some functional or the optimal middle curved concrete vault for a tunnel along which a uniform minimum compression are two typical examples. In these two examples the objective functional depends on the geometry of the boundary that can be either a curve (in case of 2D problems) or a surface boundary (in 3D problems). Typically, optimization is achieved by means of an iterative process which requires the computation of gradients of the objective function with respect to design variables. Gradients can by computed in a variety of ways, although adjoint methods either continuous or discrete ones are the more efficient ones when they are applied in different technical branches. In this paper the adjoint continuous method is introduced in a systematic way to this type of problems and an illustrative simple example, namely the finding of an optimal shape tunnel vault immersed in a linearly elastic terrain, is presented.Garcia-Palacios, J.; Castro, C.; Samartin, A. (2009). Optimal boundary geometry in an elasticity problem: a systematic adjoint approach. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/654

Effects of intensity, attention and medication on auditory-evoked potentials in patients with fibromyalgia

Fibromyalgia (FM) has been associated to an increased processing of somatosensory stimuli, but its generalization to other sensory modalities is under discussion. To clarify this, we studied auditory event-related potentials (AEPs) to stimuli of different intensity in patients with FM and healthy controls (HCs), considering the effects of attention mechanisms and medication. We performed two experiments: In study 1 (n = 50 FM, 60 HCs), the stimuli were presented randomly within the sequence; in study 2 (n = 28 FM, 30 HCs), they were presented in blocks of the same intensity. We analyzed intensity and group effects on N1-P2 amplitude and, only for the FM group, the effect of medication and the correlation between AEPs and clinical variables. Contrary to the expectation, the patients showed a trend of reduced AEPs to the loudest tones (study 1) or no significant differences with the HCs (study 2). Medication with central effects significantly reduced AEPs, while no significant relationships between the N1-P2 amplitude/intensity function and patients' symptoms were observed. The findings do not provide evidence of augmented auditory processing in FM. Nevertheless, given the observed effect of medication, the role of sensory amplification as an underlying pathophysiological mechanism in fibromyalgia cannot be discarded.Spanish Government (Ministerio de ciencia e Innovación; ref PSI2009-14555 and, Ministerio de Economía y Competitividad; ref PSI2013-45818-R) and from the Galician Government (Consellería de Cultura, Educación e Ordenación Universitaria; axudas para a consolidación e Estruturación de unidades de investigación competitivas do Sistema universitario de Galicia; grant number GPC 2014/047). A.G.V. was supported by a grant from the Portuguese Foundation for Science and Technology within the scope of the Individual Call to Scientific Employment Stimulus 2017. N.S.V. was supported by a grant from Spanish Government (Ministerio de Economía y Competitividad; grant number BES-2017-082684

Non-Hodgkin's lymphoma, obesity and energy homeostasis polymorphisms

A population-based case–control study of lymphomas in England collected height and weight details from 699 non-Hodgkin's lymphoma (NHL) cases and 914 controls. Obesity, defined as a body mass index (BMI) over 30 kg m−2 at five years before diagnosis,, was associated with an increased risk of NHL (OR=1.5, 95% CI 1.1–2.1). The excess was most pronounced for diffuse large B-cell lymphoma (OR=1.9, 95% CI 1.3–2.8). Genetic variants in the leptin (LEP 19G>A, LEP −2548G>A) and leptin receptor genes (LEPR 223Q>R), previously shown to modulate NHL risk, as well as a polymorphism in the energy regulatory gene adiponectin (APM1 276G>T), were investigated. Findings varied with leptin genotype, the risks being decreased with LEP 19AA (OR=0.7, 95% CI 0.5–1.0) and increased with LEP −2548GA (OR=1.3, 95% CI 1.0–1.7) and −2548AA (OR=1.4, 95% CI 1.0–1.9), particularly for follicular lymphoma. These genetic findings, which were independent of BMI, were stronger for men than women

Correction: Neuronal Hyperactivity Disturbs ATP Microgradients, Impairs Microglial Motility, and Reduces Phagocytic Receptor Expression Triggering Apoptosis/Microglial Phagocytosis Uncoupling

Correction de l'article DOI: 10.1371/journal.pbio.100246

Evaluation of appendicitis risk prediction models in adults with suspected appendicitis

Background Appendicitis is the most common general surgical emergency worldwide, but its diagnosis remains challenging. The aim of this study was to determine whether existing risk prediction models can reliably identify patients presenting to hospital in the UK with acute right iliac fossa (RIF) pain who are at low risk of appendicitis. Methods A systematic search was completed to identify all existing appendicitis risk prediction models. Models were validated using UK data from an international prospective cohort study that captured consecutive patients aged 16–45 years presenting to hospital with acute RIF in March to June 2017. The main outcome was best achievable model specificity (proportion of patients who did not have appendicitis correctly classified as low risk) whilst maintaining a failure rate below 5 per cent (proportion of patients identified as low risk who actually had appendicitis). Results Some 5345 patients across 154 UK hospitals were identified, of which two‐thirds (3613 of 5345, 67·6 per cent) were women. Women were more than twice as likely to undergo surgery with removal of a histologically normal appendix (272 of 964, 28·2 per cent) than men (120 of 993, 12·1 per cent) (relative risk 2·33, 95 per cent c.i. 1·92 to 2·84; P < 0·001). Of 15 validated risk prediction models, the Adult Appendicitis Score performed best (cut‐off score 8 or less, specificity 63·1 per cent, failure rate 3·7 per cent). The Appendicitis Inflammatory Response Score performed best for men (cut‐off score 2 or less, specificity 24·7 per cent, failure rate 2·4 per cent). Conclusion Women in the UK had a disproportionate risk of admission without surgical intervention and had high rates of normal appendicectomy. Risk prediction models to support shared decision‐making by identifying adults in the UK at low risk of appendicitis were identified

Optimal financial crises: A note on Allen and Gale

This note provides an example of an optimal banking panic. We construct a model in which a banking panic is triggered by the banker, not the depositors. When the banker receives a pessimistic information on the return on the bank’s assets, he liquidates them prematurely in order to protect his capital. In the face of this liquidation, all depositors withdraw their funds prematurely. The premature liquidation of the bank’s assets strengthens the bank’s balance sheet. As a result, the banking panic does not cause bank failure and the government should not try to prevent the panic. Such a panic occured in 1857 in the United States. Copyright Springer Science + Business Media, LLC 2006Optimal banking panic, Bank failure, Deposit insurance, Panic of 1857,

Dietary intake and nutritional status of children and adolescents in Europe

The objective of this project was to collect and evaluate data on nutrient intake and status across Europe and to ascertain whether any trends could be identified. Surveys of dietary intake and status were collected from across Europe by literature search and personal contact with country experts. Surveys that satisfied a defined set of criteria - published, based on individual intakes, post-1987, adequate information provided to enable its quality to be assessed, small age bands, data for sexes separated above 12 years, sample size over 25 and subjects representative of the population - were selected for further analysis. In a small number of cases, where no other data for a country were available or where status data were given, exceptions were made. Seventy-nine surveys from 23 countries were included, and from them data on energy, protein, fats, carbohydrates, alcohol, vitamins, minerals and trace elements were collected and tabulated. Data on energy, protein, total fat and carbohydrate were given in a large number of surveys, but information was very limited for some micronutrients. No surveys gave information on fluid intake and insufficient gave data on food patterns to be of value to this project. A variety of collection methods were used, there was no consistency in the ages of children surveyed or the age cut-off points, but most surveys gave data for males and females separately at all ages. Just under half of the surveys were nationally representative and most of the remainder were regional. Only a small number of local surveys could be included. Apart from anthropometric measurements, status data were collected in only seven countries. Males had higher energy intakes than females, energy intake increased with age but levelled off in adolescent girls. Intakes of other nutrients generally related to energy intakes. Some north-south geographical trends were noted in fat and carbohydrate intakes, but these were not apparent for other nutrients. Some other trends between countries were noted, but there were also wide variations within countries. A number of validation studies have shown that misreporting is a major problem in dietary surveys of children and adolescents and so all the dietary data collected for this project should be interpreted and evaluated with caution. In addition, dietary studies rely on food composition tables for the conversion of food intake data to estimated nutrient intakes and each country uses a different set of food composition data which differ in definitions, analytical methods, units and modes of expression. This can make comparisons between countries difficult and inaccurate. Methods of measuring food intake are not standardised across Europe and intake data are generally poor, so there are uncertainties over the true nutrient intakes of children and adolescents across Europe. There are insufficient data on status to be able to be able to draw any conclusions about the nutritional quality of the diets of European children and adolescents