Expanding scroll rings and negative tension turbulence in a model of excitable media

Scroll waves in excitable media, described by the Barkley model, are studied. In the parameter region of weak excitability, negative tension of wave filaments is found. It leads to expansion of scroll rings and instability of wave filaments. A circular filament tends to stretch, bend, loop, and produce an expanding tangle that fills up the volume. The filament does not undergo fragmentation before it touches the boundaries. Statistical properties of such Winfree turbulence of scroll waves are numerically investigated.

Differences based on fine motor behaviour in Parkinson's patients compared to an age matched control group in proprioceptive and visuo-proprioceptive test conditions

Personality differences based on fine motor precision performance were studied in early stage Parkinson's patients and an age-matched control group under two different test conditions: proprioceptive + visual information and proprioceptive information alone. A comparative data analysis for deviations of three measured movement types (transversal, frontal and sagittal) was done for both hands (dominant and non-dominant) with relation to personality dimensions. There were found significant differences between the two groups in decision making dimension and emotionality. After splitting the data for gender subgroups, some significant differences were found for men but not for women. The differences in fine motor task performance varied, being better in some directions for the Parkinson"s patients and worse in others. The findings may suggest that medication has both positive and negative effects on motor performance and provoke personality changes, being more pronounced in men.

Endorectal Magnetic Resonance Imaging and Spectroscopy Are Useful for Selecting Candidates for Biopsy among Patients with Persistently Elevated Prostate Specific Antigen

To evaluate the efficacy of endorectal Magnetic Resonance Imaging (MRI) and Magnetic Resonance Spetroscopic Imaging (MRSI) combined with total prostate-specific antigen (tPSA) and free prostate-specific antigen (fPSA) in selecting candidates for biopsy. Subjects and Methods: 246 patients with elevated tPSA (median: 7.81 ng/ml) underwent endorectal MRI and MRSI before Transrectal Ultrasound (TRUS) biopsy (10 peripheral + 2 central cores); patients with positive biopsies were treated with radical intention; those with negative biopsies were followed up and underwent MRSI before each additional biopsy if tPSA rose persistently. Mean follow-up: 27.6 months. We compared MRI, MRSI, tPSA, and fPSA with histopathology by sextant and determined the association between the Gleason score and MRI and MRSI. We determined the most accurate combination to detect prostate cancer (PCa) using receiver operating curves; we estimated the odds ratios (OR) and calculated sensitivity, specificity, and positive and negative predictive values. Results: No difference in tPSA was found between patients with and without PCa (p = 0.551). In the peripheral zone, the risk of PCa increased with MRSI grade; patients with high-grade MRSI had the greatest risk of PCa over time (OR = 328.6); the model including MRI, MRSI, tPSA, and fPSA was more accurate (Area under Curve: AUC = 95.7%) than MRI alone (AUC = 85.1%) or fPSA alone (AUC = 78.1%), but not than MRSI alone (94.5%). In the transitional zone, the model was less accurate (AUC = 84.4%). The association (p = 0.005) between MRSI and Gleason score was significant in both zones. Conclusions: MRSI is useful in patients with elevated tPSA. High-grade MRSI lesions call for repeated biopsies. Men with negative MRSI may forgo further biopsies because a significantly high Gleason lesion is very unlikely

Personality traits and psychopathology predict burnout symptoms after two years in a sample of Catalan police officers

The operational aspects of psychological assessment are well documented (e.g. Murphy and Davidshofer, 1994). Essentially, the process involves the administration of one or more valid psychological tests in order to assess a person’s suitability to a task or situation. The resulting data and report are then used by police psychologists to assist in determining the suitability of the applicant for police duties. In Catalunya, this task is carried out during basic training for police career agent in the evaluation of psychological conditions for the use of the weapon. Police work can be one of the most stressful jobs, and it frequently leads to the development of burnout syndrome. In their day-to-day tasks, police officers are constantly subjected to various stressors (de la Fuente, Aguayo, Vargas and Cañadas, 2013). The most widely accepted definition of the burnout syndrome is one that describes it as a response to chronic work stress made up of three components: emotional exhaustion, depersonalisation and low personal accomplishment (Maslach & Jackson, 1981). Some studies showed that personality characteristics, and positive and negative affectivity explained significant variance in each of the burnout dimensions (Alarcon, Eschleman and Bowling, 2009).

Drug abuse, brain calcification and glutamate-induced neurodegeneration

Positive and negative reinforcing systems are part of the mechanism of drug dependence. Drugs with abuse potential may change the manner of response to negative emotional stimuli, activate positive emotional reactions and possess primary reinforcing properties. Catecholaminergic and peptidergic processes are of importance in these mechanisms. Current research needs to understand the types of adaptations that underlie the particularly long-lived aspects of addiction. Presently, glutamate is candidate to play a role in the enduring effects of drugs of abuse. For example, it participates in the chronic pathological changes of corticostriatal terminals produced by methamphetamine. At the synaptic level, a link between over-activation of glutamate receptors, [C(a2+)](i) increase and neuronal damage has been clearly established leading to neurodegeneration. Thus, neurodegeneration can start after an acute over-stimulation whose immediate effects depend on a diversity of calcium-activated mechanisms. If sufficient, the initial insult results in calcification and activation of a chronic on-going process with a progressive loss of neurons. At present, long-term effects of drug dependence underlie an excitotoxicity process linked to a polysynaptic pathway that dynamically regulates synaptic glutamate. Retaliatory mechanisms include energy capability of the neurons, inhibitory systems and cytoplasmic calcium precipitation as part of the neuron-glia interactions. This paper presents an integrated view of these molecular and cellular mechanisms to help understand their relationship and interdependence in a chronic pathological process that suggest new targets for therapeutic intervention.

Avaluació ambiental de la recollida de residus municipals de Sant Boi de Llobregat

La gestió dels residus municipals ha d’avançar cap a la sostenibilitat per tal de poder fer front al gran volum de residus que es generen actualment i no malmetre el medi ambient. Aquest fet motiva a l’elaboració d’aquest projecte que es centra en l’anàlisi del procés de recollida dels residus municipals. L’estudi realitza en primer lloc una avaluació ambiental de la recollida global i una avaluació ambiental específica de la recollida de la fracció Resta mitjançant el programari SIMUR (desenvolupada per l’Agència d’Ecologia Urbana de Barcelona). Amb aquesta eina de simulació de models de gestió de residus municipal es calcula el balanç de massa, el balanç energètic, el balanç d’emissions i el balanç econòmic del procés de recollida. La metodologia per al desenvolupament de la segona fase del projecte es basa en la realització de treball de camp per al disseny de taules descriptives dels circuits de recollida de la fracció Resta, que permeten comparar-los entre sí i aconseguir l’objectiu d’avaluar l’eficiència dels sistemes de recollida de càrrega lateral i posterior de la fracció. L’assoliment dels objectius permet fer-se una idea de l’estat actual de la recollida dels residus de Sant Boi, identificant-ne els punts forts i febles i plantejant propostes de millora encarades a aconseguir una futura generació i recollida de residus més respectuosa amb l’entorn.

Estudi del jardí romàntic del Palau Novella, Parc del Garraf

Durant molts anys, els jardins del Palau Novella han patit una sèrie de canvis que han desembocat en el seu abandonament i degradació. La falta de gestió i manteniment ha comportat l’aparició de fitopatologies en una part important dels individus, així com la colonització d’espècies invasores, tant de flora com de faun,a o la degradació dels elements arquitectònics. D’altra banda, la seva importància com a connector o la presència d’arbres i comunitats d’especial interès, li atorguen a la zona un gran valor a nivell ecològic. Per tant, tant per a la seva protecció, com per a la millora de les condicions actuals de degradació, seran necessàries una sèrie de mesures correctores que ajudin a restaurar i conservar la zona, de manera que, l’objectiu principal d’aquest estudi, serà l’avaluació de tots els factors, tant positius com negatius, per tal de poder elaborar les mesures esmentades.

Acute Damage to the Posterior Limb of the Internal Capsule on Diffusion Tensor Tractography as an Early Imaging Predictor of Motor Outcome after Stroke

Background and Purpose Early prediction of motor outcome is of interest in stroke management. We aimed to determine whether lesion location at DTT is predictive of motor outcome after acute stroke and whether this information improves the predictive accuracy of the clinical scores. Methods We evaluated 60 consecutive patients within 12 hours of MCA stroke onset. We used DTT to evaluate CST involvement in the MC and PMC, CS, CR, and PLIC and in combinations of these regions at admission, at day 3, and at day 30. Severity of limb weakness was assessed using the m-NIHSS (5a, 5b, 6a, 6b). We calculated volumes of infarct and FA values in the CST of the pons. Results Acute damage to the PLIC was the best predictor associated with poor motor outcome, axonal damage, and clinical severity at admission (P&.001). There was no significant correlation between acute infarct volume and motor outcome at day 90 (P=.176, r=0.485). The sensitivity, specificity, and positive and negative predictive values of acute CST involvement at the level of the PLIC for 4 motor outcome at day 90 were 73.7%, 100%, 100%, and 89.1%, respectively. In the acute stage, DTT predicted motor outcome at day 90 better than the clinical scores (R2=75.50, F=80.09, P&.001). Conclusions In the acute setting, DTT is promising for stroke mapping to predict motor outcome. Acute CST damage at the level of the PLIC is a significant predictor of unfavorable motor outcome.

Variability of North Atlantic hurricanes: seasonal versus individual-event features

Tropical cyclones are affected by a large number of climatic factors, which translates into complex patterns of occurrence. The variability of annual metrics of tropical-cyclone activity has been intensively studied, in particular since the sudden activation of the North Atlantic in the mid 1990’s. We provide first a swift overview on previous work by diverse authors about these annual metrics for the North-Atlantic basin, where the natural variability of the phenomenon, the existence of trends, the drawbacks of the records, and the influence of global warming have been the subject of interesting debates. Next, we present an alternative approach that does not focus on seasonal features but on the characteristics of single events [Corral et al., Nature Phys. 6, 693 (2010)]. It is argued that the individual-storm power dissipation index (PDI) constitutes a natural way to describe each event, and further, that the PDI statistics yields a robust law for the occurrence of tropical cyclones in terms of a power law. In this context, methods of fitting these distributions are discussed. As an important extension to this work we introduce a distribution function that models the whole range of the PDI density (excluding incompleteness effects at the smallest values), the gamma distribution, consisting in a powerlaw with an exponential decay at the tail. The characteristic scale of this decay, represented by the cutoff parameter, provides very valuable information on the finiteness size of the basin, via the largest values of the PDIs that the basin can sustain. We use the gamma fit to evaluate the influence of sea surface temperature (SST) on the occurrence of extreme PDI values, for which we find an increase around 50 % in the values of these basin-wide events for a 0.49 C SST average difference. Similar findings are observed for the effects of the positive phase of the Atlantic multidecadal oscillation and the number of hurricanes in a season on the PDI distribution. In the case of the El Niño Southern oscillation (ENSO), positive and negative values of the multivariate ENSO index do not have a significant effect on the PDI distribution; however, when only extreme values of the index are used, it is found that the presence of El Niño decreases the PDI of the most extreme hurricanes.

Emphatic Polarity from Latin to Romance

This paper offers an analysis of some emphatic polarity constructions in Spanish and Catalan from a diachronic and comparative perspective. We focus on the syntactic processes involved in the verbalization of this polarity, in both its positive and negative expression. Our main proposal is that the markers used in Spanish and Catalan (as well as other Romance languages) to reinforce polarity have acquired their status as the consequence of a focalization process. It will be argued that these elements have undergone leftward movement from their base-generated hierarchically low position to a prominent position in the left periphery of the sentence (see Rizzi 1997) and subsequently experienced a progressive bleaching of their original value (which is related to a verbal denotation) to end up being reanalyzed / grammaticalized as polarity markers

Automatic Extraction of Polar Adjectives for the Creation of Polarity Lexicons

Automatic creation of polarity lexicons is a crucial issue to be solved in order to reduce time andefforts in the first steps of Sentiment Analysis. In this paper we present a methodology based onlinguistic cues that allows us to automatically discover, extract and label subjective adjectivesthat should be collected in a domain-based polarity lexicon. For this purpose, we designed abootstrapping algorithm that, from a small set of seed polar adjectives, is capable to iterativelyidentify, extract and annotate positive and negative adjectives. Additionally, the methodautomatically creates lists of highly subjective elements that change their prior polarity evenwithin the same domain. The algorithm proposed reached a precision of 97.5% for positiveadjectives and 71.4% for negative ones in the semantic orientation identification task.

Principales características geoambientales en la región del alto Fluvià (Gerona)

This study is about the main characteristics of a large area in the province of Girona, the utilization of which has been historically poor, basically due to gecsnorphological causes. The analysis has been made considering the possibilities -both positive and negative - that the geological medium offers by appropiate use of the area, bearing in mind the possible impacts that these uses could have on the medium. The conclusions drawn from this study are shown in a series of maps

Análisis de la fiabilidad de indicadores para sistemas de seguimiento de precios en los mercados

Para este trabajo se ha desarrollado un programa en Matlab, que nos permite realizar ensayos con algunas de las herramientas fundamentales del análisis técnico. Concretamente nos hemos centrado en el “Indicador de Movimiento Direccional” de Wilder. El programa está formado por seis funciones que permiten descargar datos, hacer la simulación del indicador, ajustar automáticamente algunos de sus parámetros y presentar los resultados obtenidos en la simulación. Con los experimentos y simulaciones realizadas se ha visto la importancia de escoger adecuadamente los períodos de ±DIs (indicadores direccionales positivo y negativo) y el ADX (Average Directional Movement Index). También hemos visto que la reglas decisión apuntadas por autores de reconocido prestigio como Cava y Ortiz ,no siempre se comportan como cabría esperar. Se propone mejorar el rendimiento y la fiabilidad de este indicador Incluyendo alguna media móvil de los precios y el volumen de contratación, en los criterios de decisión. También se podría mejorar implementando un sistema para que se pudiesen autoajustar los criterios de decisión.

Subjectively adapted high capacity lossless image data hiding based on prediction errors

This article reports on a lossless data hiding scheme for digital images where the data hiding capacity is either determined by minimum acceptable subjective quality or by the demanded capacity. In the proposed method data is hidden within the image prediction errors, where the most well-known prediction algorithms such as the median edge detector (MED), gradient adjacent prediction (GAP) and Jiang prediction are tested for this purpose. In this method, first the histogram of the prediction errors of images are computed and then based on the required capacity or desired image quality, the prediction error values of frequencies larger than this capacity are shifted. The empty space created by such a shift is used for embedding the data. Experimental results show distinct superiority of the image prediction error histogram over the conventional image histogram itself, due to much narrower spectrum of the former over the latter. We have also devised an adaptive method for hiding data, where subjective quality is traded for data hiding capacity. Here the positive and negative error values are chosen such that the sum of their frequencies on the histogram is just above the given capacity or above a certain quality.

Spanish adaptation of the Expectancy Questionnaire (EQ) about alcohol effects in adolescents

Background: Alcohol-related expectancies are especially relevant in relation to alcohol consumption during adolescence. The main aim of this study was to adapt and translate into Spanish (Castilian) the Expectancy Questionnaire (EQ), and to study its psychometric properties in adolescents. Method: The sample was composed of 514 adolescents (57.20% female, mean age = 15.21; SD = .63) who completed the EQ and the alcohol consumption questionnaire AIS-UJI. Results: Confi rmatory factor analysis indicated that an eight-factor model, grouped into two general factors of positive and negative expectancies, had acceptable fi t indices. Cronbach’s alphas ranged from .75 to .96. Finally, the structural equation model showed that positive expectancies were positively related to alcohol use, whereas negative expectancies were negatively related to drinking. Conclusions: Results showed that the Spanish version of the EQ for adolescents is a valid and reliable questionnaire to measure expectancies about alcohol effects.