86 resultados para second position


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Cancer treatment involves the participation of multiple medical specialties and, as our knowledge of the disease increases, this fact becomes even more apparent. The degree of multidisciplinarity is determined by several factors, which include the severity and type of disease, the increasing diversity in the available pharmacological and non-pharmacological therapies, and the range of specialists involved in cancer therapy, such as medical oncologists, radiotherapists, gynecologists, gastroenterologists, urologists, surgeons, and pneumologists, among others. Across Europe, the situation of cancer care can be variable due to the diversity of health systems, differences in drug reimbursement, and the degree of establishment of Medical Oncology as a medical specialty in the European Union states.

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We studied the mercury contamination of 13 species of seabirds breeding on Bird Island, South Georgia, in 1998. Total mercury concentrations in body feather samples of birds caught at their breeding colonies were determined. Among the species, grey-headed albatross (8933 ng g-1) and southern giant petrel (7774 ng g-1) showed the highest, and gentoo penguin (948 ng g-1) the lowest body feather mercury concentrations. Mercury levels were negatively correlated with the proportion of crustaceans (mainly krill) in the species¹ diets, suggesting that the trophic level is the most important factor in explaining the variation of mercury concentrations in Antarctic seabirds. In 4 species studied for age effects among adult birds (grey-headed and black-browed albatross, northern and southern giant petrel), no age-dependent variation in mercury levels was found. Sex differences were also assessed: female gentoo penguins had lower mercury levels than males, which may be related to the elimination of part of the mercury body burden by females into eggs. In contrast, northern giant petrel males had lower levels than females, which may be related to a higher consumption by males of carrion from Antarctic fur seals. In grey-headed albatrosses, mercury levels were 113% higher than in 1989, when this species was investigated at the same site, indicating a possible increase in mercury pollution of the Southern Ocean during the last decade.

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This paper proposes a pose-based algorithm to solve the full SLAM problem for an autonomous underwater vehicle (AUV), navigating in an unknown and possibly unstructured environment. The technique incorporate probabilistic scan matching with range scans gathered from a mechanical scanning imaging sonar (MSIS) and the robot dead-reckoning displacements estimated from a Doppler velocity log (DVL) and a motion reference unit (MRU). The proposed method utilizes two extended Kalman filters (EKF). The first, estimates the local path travelled by the robot while grabbing the scan as well as its uncertainty and provides position estimates for correcting the distortions that the vehicle motion produces in the acoustic images. The second is an augment state EKF that estimates and keeps the registered scans poses. The raw data from the sensors are processed and fused in-line. No priory structural information or initial pose are considered. The algorithm has been tested on an AUV guided along a 600 m path within a marina environment, showing the viability of the proposed approach

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Understanding nanomaterial interactions within cells is of increasing importance for assessing their toxicity and cellular transport. Here, we developed nanovesicles containing bioactive cationic lysine-based amphiphiles, and assessed whether these cationic compounds increase the likelihood of intracellular delivery and modulate toxicity. We found different cytotoxic responses among the formulations, depending on surfactant, cell line and endpoint assayed. The induction of mitochondrial dysfunction, oxidative stress and apoptosis were the general mechanisms underlying cytotoxicity. Fluorescence microscopy analysis demonstrated that nanovesicles were internalized by HeLa cells, and evidenced that their ability to release endocytosed materials into cell cytoplasm depends on the structural parameters of amphiphiles. The cationic charge position and hydrophobicity of surfactants determine the nanovesicle interactions within the cell and, thus, the resulting toxicity and intracellular behavior after cell uptake of the nanomaterial. The insights into some toxicity mechanisms of these new nanomaterials contribute to reducing the uncertainty surrounding their potential health hazards.

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Understanding how marine predators interact is a scientific challenge. In marine ecosystems, segregation in feeding habits has been largely described as a common mechanism to allow the coexistence of several competing marine predators. However, little is known about the feeding ecology of most species of chondrichthyans, which play a pivotal role in the structure of marine food webs worldwide. In this study, we examined the trophic ecology of 3 relatively abundant chondrichthyans coexisting in the Mediterranean Sea: the blackmouth catshark Galeus melastomus , the velvet belly lanternshark Etmopterus spinax and the rabbit fish Chimaera monstrosa. To examine their trophic ecology and interspecific differences in food habits, we combined the analysis of stomach content and stable isotopes. Our results highlighted a trophic segregation between C. monstrosa and the other 2 species. G. melastomus showed a diet composed mainly of cephalopods, while E. spinax preyed mainly on shrimps and C. monstrosa on crabs. Interspecific differences in the trophic niche were likely due to different feeding capabilities and body size. Each species showed different isotopic niche space and trophic level. Specifically, C. monstrosa showed a higher trophic level than E. spinax and G. melastomus. The high trophic levels of the 3 species highlighted their important role as predators in the marine food web. Our results illustrate the utility of using complementary approaches that provide information about the feeding behaviour at short (stomach content) and long-term scales (stable isotopes), which could allow more efficient monitoring of marine food-web changes in the study area.

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This paper presents the discovery of the oldest Roman camp on the Iberian Peninsula, a camp from the Second Punic War situated in La Palma (Tarragona, Spain), by the mouth of the River Ebro. Although no structural remains have been found, the site's strategic in- terest along with many coins, arms and fragments of amphoras and other objects indicate that a military camp was established here between 218 and 209 BC. Written sources, mainly Polybius and Livy, suggest that La Palma was where the legions of Publius Cornelius Scipio gathered before the attack on Carthago Nova in 209 BC. The paper ends by suggesting that La Palma may be the Roman camp of Nova Classis mentioned by Livy during the events of the war in 217 BC.

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Performance-based studies on the psychological nature of linguistic competence can conceal significant differences in the brain processes that underlie native versus nonnative knowledge of language. Here we report results from the brain activity of very proficient early bilinguals making a lexical decision task that illustrates this point. Two groups of SpanishCatalan early bilinguals (Spanish-dominant and Catalan-dominant) were asked to decide whether a given form was a Catalan word or not. The nonwords were based on real words, with one vowel changed. In the experimental stimuli, the vowel change involved a Catalan-specific contrast that previous research had shown to be difficult for Spanish natives to perceive. In the control stimuli, the vowel switch involved contrasts common to Spanish and Catalan. The results indicated that the groups of bilinguals did not differ in their behavioral and event-related brain potential measurements for the control stimuli; both groups made very few errors and showed a larger N400 component for control nonwords than for control words. However, significant differences were observed for the experimental stimuli across groups: Specifically, Spanish-dominant bilinguals showed great difficulty in rejecting experimental nonwords. Indeed, these participants not only showed very high error rates for these stimuli, but also did not show an error-related negativity effect in their erroneous nonword decisions. However, both groups of bilinguals showed a larger correctrelated negativity when making correct decisions about the experimental nonwords. The results suggest that although some aspects of a second language system may show a remarkable lack of plasticity (like the acquisition of some foreign contrasts), first-language representations seem to be more dynamic in their capacity of adapting and incorporating new information. &

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The present study builds on a previous proposal for assigning probabilities to the outcomes computed using different primary indicators in single-case studies. These probabilities are obtained comparing the outcome to previously tabulated reference values and reflect the likelihood of the results in case there was no intervention effect. The current study explores how well different metrics are translated into p values in the context of simulation data. Furthermore, two published multiple baseline data sets are used to illustrate how well the probabilities could reflect the intervention effectiveness as assessed by the original authors. Finally, the importance of which primary indicator is used in each data set to be integrated is explored; two ways of combining probabilities are used: a weighted average and a binomial test. The results indicate that the translation into p values works well for the two nonoverlap procedures, with the results for the regression-based procedure diverging due to some undesirable features of its performance. These p values, both when taken individually and when combined, were well-aligned with the effectiveness for the real-life data. The results suggest that assigning probabilities can be useful for translating the primary measure into the same metric, using these probabilities as additional evidence on the importance of behavioral change, complementing visual analysis and professional's judgments.

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Rodrigo, Chamizo, McLaren, & Mackintosh (1997) demonstrated the blocking effect in a navigational task using a swimming pool: rats initially trained to use three landmarks (ABC) to find an invisible platform learned less about a fourth landmark (X) added later than did rats trained from the outset with these four landmarks (ABCX). The aim of the experiment reported here was to demonstrate unblocking using a similar procedure as in the previous work. Three groups of rats were initially trained to find an invisible platfom in the presence of three landmarks: ABC for the Blocking and Unblocking groups and LMN for the Control group. Then, all animals were trained to find the platform in the presence of four landmarks, ABCX. In this second training, unlike animals in the Blocking group to which only a new landmark (X) was added in comparison to the first training, the animals in the Unblocking group also had a change in the platform position. In the Control group, both the four landmarks and the platform position were totally new at the beginning of this second training. As in Rodrigo et al. (1997) a blocking effect was found: rats in the Blocking group learned less with respect to the added landmark (X) than did animals in the Control group. However, rats in the Unblocking group learned about the added landmark (X) as well as did animals in the Control group. The results are interpreted as an unblocking effect due to a change in the platform position between the two phases of training, similarly to what is normal in classical conditioning experiments, in which a change in the conditions of reinforcement between the two training phases of a blocking design produce an attenuation or elimination of this effect. These results are explained within an error-correcting connectionist account of spatial navigation (McLaren, 2002).

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Aquest projecte consisteix en acoblar una càmera web uEye en una de les extremitats d'un robot industrial (ABB Irc5). Aquest robot, es mourà en cas què es detecti una cara a través de la webcam. L'objectiu és intentar que la cara es situï sempre al mig de la imatge captada per la càmera. Podem dividir les tasques d'aquest projecte amb 4 fases diferents. A continuació expliquem les diferents etapes. La Càmera uEye s'encarrega de capturar imatges i passar-les a un PC utilitzant Python. La funció de Detecció de Cares ens indica la posició i dimensions de la cara. Tot seguit, la funció LabJack s'encarrega de canviar els valors digitals de les 5 senyals mitjançant programació amb Python. Per últim el Robot ABB interpreta el valor d'aquestes 5 senyals i es desplaça mitjançant petits increments amb l'objectiu de situar la cara al mig de la imatge capturada.