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The present study was carried out to examine how the event-related potentials to fragmentation predict recognition success. Stimuli were abstract meaningless figures that were either complete or fragmented to various extents but still recoverable. Stimuli were first encoded as part of a symmetry discrimination task. In a subsequent recognition phase, encoded stimuli were presented complete along with never presented stimuli and participants performed an old/new discrimination task. Fragmentation stimuli elicited more negative ERPs than complete figures over the frontal, central and parietal areas between 180 and 260 ms, and over the occipito-temporal areas between 220 and 340 ms. Only this latter effect was modulated as a function of whether stimuli were recognized or not during the recognition phase of the memory test. More specifically, the effect occurred for stimuli that were later forgotten and was absent for stimuli that were later recognized. This ERP to fragmentation, the occipito-temporal N frag , possibly reflects the brain response to encoding difficulty, and is thus predictive of recognition performance.

We examined whether correlations previously found between symptoms of schizophrenia patients and the amplitude of an event-related potential (ERP), the N400, could be also found between schizotypal experiences of healthy subjects and the N400. We chose a semantic categorization task previously used with patients. Schizotypal experiences were measured with the schizotypal personality questionnaire (SPQ). The effects of the other factors were controlled for when assessing the correlations between each SPQ factor and N400s. These correlations were assessed at each electrode site to see whether their distribution on the scalp follows that of the N400 effect. Disorganization and interpersonal scores were found to correlate with ERPs in the N400 time window, as previously reported for the comparable symptoms of patients. However, the scalp distribution of these correlations differed from that of the N400 effect.

There are currently stimuli with published norms available to study several psychological aspects of language and visual cognitions. Norms represent valuable information that can be used as experimental variables or systematically controlled to limit their potential influence on another experimental manipulation. The present work proposes 480 photo stimuli that have been normalized for name, category, familiarity, visual complexity, object agreement, viewpoint agreement, and manipulability. Stimuli are also available in grayscale, blurred, scrambled, and line-drawn version. This set of objects, the Bank Of Standardized Stimuli (BOSS), was created specifically to meet the needs of scientists in cognition, vision and psycholinguistics who work with photo stimuli.

International audience; Music Information Retrieval systems are commonly built on a feature extraction stage. For applications involving automatic classification (e.g. speech/music discrimination , music genre or mood recognition, ...), traditional approaches will consider a large set of audio features to be extracted on a large dataset. In some cases, this will lead to computationally intensive systems and there is, therefore, a strong need for efficient feature extraction. In this paper, a new audio feature extraction software, YAAFE 1 , is presented and compared to widely used libraries. The main advantage of YAAFE is a significantly lower complexity due to the appropriate exploitation of redundancy in the feature calculation. YAAFE remains easy to configure and each feature can be parameterized independently. Finally, the YAAFE framework and most of its core feature library are released in source code under the GNU Lesser General Public License.

Purpose: To evaluate the ocular surface changes induced by contact lens wear. Methods: Data of 7 tolerant contact lens wearers, 7 non-tolerant contact lens wearers and 7 healthy subjects were collected. Every patient underwent a thorough ophthalmic examination and tear osmolarity test, conjunctival impression cytology and meibomian lipid sampling. Symptoms, Break-Up Time (BUT), tear osmolarity, conjunctival expression of human leucocyte antigen (HLA) DR and meibomian fatty acid composition were evaluated. Results: Twenty one subjects (8 men and 13 women) were included (42 eyes). Symptoms reported by tolerant and non-tolerant contact lens wearers were as follows: superficial foreign body sensation (29% vs 21%), burning (14% vs 21%) and ocular dryness (28% vs 78%). No symptoms were reported by healthy subjects. There was no significant difference in tear osmolarity (p=0.63) and meibomian fatty acid composition (p=0.97) in both groups. Break-up time was significantly lower in tolerant (p

Repetition has often been associated with a reduction or a suppression of semantic effects. However, several studies have reported that semantic processing can still be effective for repeated target stimuli when the context, prime word or sentence frame, changes from trial to trial. This type of context-target designs allows to study semantic associations between repeated words. However, it is not optimal to study single concepts or categories and therefore structural aspects of semantic memory. Here, we tested whether semantic effects could be observed if single-word trials were used. Concrete and Abstract words were presented multiple times in two concrete-abstract classification experiments. In the first experiment, 6 words of each category were repeatedly presented. In the second experiment, only one word of each category was used. Results of both experiments showed significant effects of concreteness on reaction times and N400-like event-related potentials (ERPs), which were comparable to those reported in non-repeated conditions. In the second experiment, in which repetitions occurring in consecutive and non-consecutive trials were contrasted, N400-like effects were observed only for non-consecutive repetitions. These findings suggest that it could be possible to study the brain activity corresponding to individual concepts in experimental designs using single-word trials, provided that consecutive repetitions are avoided.

In healthy people, enacting actions by manipulating objects improves memory compared to verbal encoding of the description of the same actions. We used this paradigm to test memory for actions in 40 stable schizophrenia participants and 24 healthy volunteers. Three encoding conditions were used and consisted of action sentences that were: 1) self-performed by the participants, 2) performed by an experimenter (observed), or 3) encoded verbally. Memory for those actions was tested in two formats. First a cued-recall task with the object as a retrieval cue was administered. Secondly source recognition was examined by asking the participants to decide in which of the three conditions each action was encoded. On cued-recall, schizophrenia participants largely benefited from self-enacting actions, reaching performance levels comparable to that of the healthy volunteers. On the source recognition test however, they showed a substantial impairment. The present study thus indicates that people with schizophrenia can benefit from the enactment effect. However, the fact that their performance was reduced considerably during source recognition relative to healthy volunteers suggests that the beneficial effect provided by enactment was mostly implicit.

The SMN1 gene is homozygously deleted for at least exon 7, interrupted or converted to a non-functional telomeric copy in most cases of proximal spinal muscular atrophies. The presence of a pseudogene hampers direct detection of the exon 7 deletion. We describe a method for the detection of the of exon 7 deletion, based on the amplification refractory mutation system (ARMS), in a multiplex PCR with fluorescent-labelled primers. The gene and pseudogene amplification products differ in the dye bound and in their size, which allows distinction of both products on electrophoresis. The pseudogene is used as an internal control, and this method gives a clear and specific pattern for the patients. Amplification is achieved with 30 cycles, and specificity is retained up to 40 cycles.

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In everyday life, objects are rarely perceived in the exact same position as they were the first time. This change of position alters the perceptual viewpoint influencing the likelihood of recognizing the object - the similarity effect. Moreover, this effect may be a contributing factor to the overall episodic memory deficits that are apparent in people with schizophrenia. The present study investigated the influence of viewpoint on memory recognition in 43 schizophrenia and 23 healthy comparison participants. Photos of target objects were presented during the encoding phase alone and then during the recognition phase (as an old object) along with never-before presented objects. The old objects, however, now appeared either from the same viewpoint (unaltered condition) or from a different viewpoint (altered condition). Participants performed an old/new discrimination task during the recognition phase. Results, for both groups, revealed better recognition performance when the viewpoint was unaltered; that is, memory recognition was sensitive to viewpoint manipulation. There was no significant interaction however, between this similarity effect and group. Thus, visual functions solicited by changing the viewpoint, as well as the influence on the encoding and the subsequent memory retrieval, are likely intact in people with schizophrenia.

The amplitude of the P300 event-related potential (ERP) has been reported to be reduced over left compared to right temporal sites in schizophrenia patients. This left temporal P300 reduction has been associated with positive symptom severity and gray matter reduction in the left superior temporal gyrus. We investigated a group of patients with a first episode of schizophrenia spectrum psychosis and a group of normal controls to verify if P300 amplitude asymmetry already exists around the time of presentation for treatment. Relative to normal control subjects, no P300 asymmetry was found in patients. Nevertheless, P300 asymmetry was correlated with the severity of positive symptoms and worse global functioning (GAF), a good predictor of poor outcome.

We tested whether the N400 event-related potential (ERP) indexes the integration of semantic knowledge in the context or whether it indexes the inhibition of activated, but inappropriate, knowledge. A distractor-prime-target word sequence was presented in each trial. Subjects had to make semantic relatedness judgments on prime-target pairs. In the first experiment, subjects had an additional task. They either had to ignore or to attend to distractors. In critical conditions, that is, when distractors were related to targets, the times to make the prime-target semantic relatedness judgments were longer when subjects had to attend to distractors than when they had to ignore them. In accordance with the inhibition hypothesis, the amplitudes of the N400 elicited by distractors were larger in the ignore than in the attend task. In the second experiment, the same distractor-prime-target triplets were used. However, there was no additional task. Subjects only had to make the prime-target semantic-relatedness judgment. They were then split in two subgroups: the good ignorers, who did not take much longer to make the judgment in critical than in control conditions, and the poor ignorers, that is, those who did take much longer. Results were again consistent with the inhibition idea. The amplitudes of the N400s evoked by distractors were larger in the good than in the poor ignorers [corrected]. The results of these two studies are taken together to support the idea that N400 index a semantic inhibition rather than an integration effort.

Overlay Networks have been designed as a promising solution to deliver new services via the use of intermediate nodes, acting as proxies or relays. This concept enables to hide the heterogeneity and variability of the underlying networks. In the Ambient Networks (ANs) project, the objectives are to study the composition and decomposition of services, the multi-radio interfaces, the user and network mobility and all the features that should address the networks dynamic, variability, change and so on. In this project, the concept of overlay networks has been selected as the means to deliver services, that should be adapted to end-users' context, regarding the access network, the location, the used device and the user's preferences. Obviously, since ANs are very dynamic, variable, the overlay network should be adaptable to fit the new environment. In this paper we present the architecture of this overlay network as well as the dynamic and secure deployment mechanisms which aim at improving the delivery of adapted services. The overlay network being created upon service providers request, an interface allowing this creation request and further configuration requests has been defined and is presented in this paper, the so-called Ambient Service Interface (ASI). Finally to prove the interest of our solution, an implementation of an IPTV services use-case is escribed.

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L'utilisation de variétés résistantes a souvent constitué la pierre angulaire de programmes de protection intégrée des cultures aux insectes ravageurs. Cependant, en vue d'arriver à une résistance de l'ensemble de l'agroécosystème, d'autres voies doivent être explorées. Des exemples sont fournis, à savoir celui des punaises des panicules sur sorgho pluvial au Mali, celui des foreurs des tiges sur sorgho repiqué au Nord-Cameroun, et celui des insectes terricoles sur riz pluvial à Madagascar. Des systèmes de culture durables par rapport aux attaques de ces ravageurs peuvent être développés, particulièrement des systèmes de culture en semis direct sur couverture végétale (SCV). Ces systèmes reproduisent les principes de la résistance de la plante-hôte au niveau de I'agroécosystème.

informational: people like to know where they stand in terms of what they think, feel, or do. Are they simply normal or do they happen to be outrageously below orabove widely popularstandards?Often,people alsorely on social comparison to motivate themselves. If getting a kick out of the comparison is the main goal of the comparison then the comparison target is likely to be some person or some group that fares slightly better. Finally, there could also be an explicit attempt at self-enhancement. By finding comparison others who are sufficiently similar yet also somewhat less knowledgeable, strong or likeable than themselves, people make sure that they will come out of the comparison with a feeling of psychological comfort. In short, people’s self-knowledge, motivation, and self-esteem crucially hang on the outcome of dozens of daily comparison operations. Although initially used in interpersonal theory contexts, the social comparison process also comes across as a major player in an impressive series of social psychology theories that focus on intergroup relations. Prominent contributions are for instance relative deprivation theory (Crosby, 1976, 1982; Guimond and Dube´-Simard, 1983; Gurr, 1970; Runciman,1966;VannemanandPettigrew,1972;WalkerandPettigrew, 1984; for a collection, see Walker and Smith, 2002), social identity theory (Tajfel, 1981; Tajfel and Turner, 1979; Turner, 1975), and selfcategorization theory (Hogg and Abrams, 1988; Oakes, Haslam and Turner, 1994; Turner et al., 1987). In all these theoretical perspectives, the selection of a particular social comparison target has been shown to exertamajorinfluenceonpeople’sbeliefs,feelings,and,indeed,behaviors. This analysis holds particularly in the case of self-categorization theory (SCT). SCT is often presented as the direct offspring of social identity

We describe building a large-scale image ontology using the WordNet lexical resources. This ontology is based on English words identifying portrayable objects. We reviewed the upper structure and interconnections of WordNet and selected only the branches leading to portrayable objects. This article explains our pruning approach to WordNet. The words, which represent portrayable objects, are then used as queries in our VIKA (VIsual KAtaloguer) system which acquires images through a web image search engine, performs content-based image indexing and clustering. Coherent images form clusters and others are rejected. So images inside clusters mostly represent the object determined by the query, and in this way image collections representing objects are created. An ontology of portrayable objects with representative images in its nodes will be a useful tool for solving the object recognition task.

Completion is the process by which the brain unifies and segregates the parts of an incomplete form. It is qualified as amodal when the form is placed behind an obstacle and modal when the form is at the foreground and closed by illusory contours. The N1, and sometimes the N2, deflections of the visual evoked potentials are known to be larger for modal figures, such as the Kanizsa triangle, than for control figures. This result is generally linked to completion or illusory contours, but it could also be related to a third process: the interpolation of the form by connecting its separate parts. To test the influence of interpolation, a modal triangle, an amodal triangle, a figure with outlined inducers, and a no-triangle figure were randomly presented to 26 subjects. The N1 evoked by the three triangle figures were all larger than the N1 to the no-triangle figure. These results suggest that the N1 amplitude is largely determined by the possibility of interpolating a form in the figure. The greatest N1 to the modal figure further suggests that interpolation may be increased by modal completion and decreased by the features that diminish the saliency of triangle in the amodal figure and the figure with outlined inducers. On the other hand, the largest N2 was evoked by the amodal figure. This effect may index processes activated in response to the great difficulty in perceiving the triangle in the amodal figure, a difficulty that is initially caused by a conflict of perceptions characterizing this figure.

The present event-related fMRI study examined in ten healthy participants neural correlates of recognition memory for intact, rearranged, and new pairs of visual stimuli. The correct categorization of both intact and rearranged pairs relative to pairs of new, never presented before stimuli relies on the retrieval of associative information whereas the discrimination of rearranged pairs from intact pairs additionally involves a recall-to-reject process by which subjects retrieve additional information to reach a recognition decision. Relative to new pairs, both intact and rearranged pairs yielded activation in inferior prefrontal cortex bilaterally and left dorsolateral prefrontal cortex. Relative to intact pairs, rearranged pairs were associated with increased activity in left dorsolateral prefrontal cortex. The latter could reflect the neural correlates of a recall-to-reject process, a pivotal process of associative recognition memory.

Defective cystic fibrosis (CF) transmembrane conductance regulator (CFTR)-mediated Cl−transport across the apical membrane of airway epithelial cells is implicated in the pathophysiology of CF lungs. A strategy to compensate for this loss is to augment Cl−transport through alternative pathways. We report here that partial correction of this defect could be attained through the incorporation of artificial anion channels into the CF cells. Introduction of GL-172, a synthetic analog of squalamine, into CFT1 cells increased cell membrane halide permeability. Furthermore, when a Cl−gradient was generated across polarized monolayers of primary human airway or Fischer rat thyroid cells in an Ussing chamber, addition of GL-172 caused an increase in the equivalent short-circuit current. The magnitude of this change in short-circuit current was ∼30% of that attained when CFTR was maximally stimulated with cAMP agonists. Patch-clamp studies showed that addition of GL-172 to CFT1 cells also increased whole cell Cl−currents. These currents displayed a linear current-voltage relationship and no time dependence. Additionally, administration of GL-172 to the nasal epithelium of transgenic CF mice induced a hyperpolarization response to perfusion with a low-Cl−solution, indicating restoration of Cl−secretion. Together, these results demonstrate that in CF airway epithelial cells, administration of GL-172 is capable of partially correcting the defective Cl−secretion.

To investigate the relationship between adrenal gland function and pressor response to noradrenaline in septic shock.Basal cortisol level, noradrenaline--mean arterial pressure dose-response curve and cortisol response to intravenous corticotrophin bolus were obtained in nine patients fulfilling usual criteria for septic shock and in six normal volunteers. In patients with septic shock, dose-response curve to noradrenaline was determined a second time 60 min after a 50 mg intravenous hydrocortisone bolus.As compared with controls, patients with septic shock had increased basal cortisol levels (mean+/-s.d.: 1564+/-818 vs 378+/-104 nmol l(-1) , P=0.002, 95% confidence interval for difference in means: [452, 1920]) and a blunted cortisol response to corticotrophin (403+/-461 vs 1132+/-195 nmol l(-1), P=0.008, [-1163, -2951). Five patients had impaired adrenal function reserve. As compared with controls, septic patients displayed a moderate and non significant decrease in pressor sensitivity to noradrenaline (P=0.112). As compared with patients with adequate adrenal response, patients with impaired adrenal function reserve showed a significant decrease in pressor sensitivity to noradrenaline (P=0.038). In septic patients, hydrocortisone improved pressor response to noradrenaline (P=0.032). This effect was more marked in patients with impaired adrenal function reserve so that, as compared with patients with adequate response, the difference was no longer significant (P=0.123).In septic shock, impaired adrenal function reserve may partly be accounted for by the depressed pressor sensitivity to noradrenaline. The latter may be substantially improved by physiological doses of hydrocortisone.

Cationic lipid-mediated gene transfer of cystic fibrosis transmembrane conductance regulator (CFTR) cDNA represents a promising approach for treatment of cystic fibrosis (CF). Here, we report on the structures of several novel cationic lipids that are effective for gene delivery to the lungs of mice. An amphiphile (#67) consisting of a cholesterol anchor linked to a spermine headgroup in a "T-shape" configuration was shown to be particularly efficacious. An optimized formulation of #67 and plasmid vector encoding chloramphenicol acetyl-transferase (CAT) was capable of generating up to 1 microgram of CAT enzyme/lung following intranasal instillation into BALB/c mice. This represents a 1,000-fold increase in expression above that obtained in animals instilled with naked pDNA alone and is greater than 100-fold more active than cationic lipids used previously for CFTR gene expression. When directly compared with adenovirus-based vectors containing similar transcription units, the number of molecules of gene product expressed using lipid-mediated transfer was equivalent to vector administration at multiplicities of infection ranging from 1 to 20. The level of transgene expression in the lungs of BALB/c mice peaked between days 1 and 4 post-instillation, followed by a rapid decline to approximately 20% of the maximal value by day 7. Undiminished levels of transgene expression in the lung could be obtained following repeated intranasal administration of #67:DOPE:pCF1-CAT in nude mice. Transfection of cells with formulations of #67:DOPE:pCF1-CFTR generated cAMP-stimulated CFTR chloride channel and fluid transport activities, two well-characterized defects associated with CF cells. Taken together, the data demonstrate that cationic lipid-mediated gene delivery and expression of CFTR in CF lungs is a viable and promising approach for treatment of the disease.