67 research outputs found
The effect of olive fruit stoning on virgin olive oil aroma
Olive fruit stoning gives rise to an important modification in olive oil aroma. The level of this modification is a function of the cultivar. An increment in the content of six-carbon compounds (C6) was
observed in olive oils obtained from the cultivars Verdial and Manzanilla, but not in the cultivar Picual. In the three cultivars under study, contents of five-carbon compounds (C5) and esters decreased as a consequence of fruit stoning. The modification of olive oil aroma composition in the cultivar Verdial caused by olive fruit stoning was observed to be due both to tissue wounding and to the absence of the olive seed during the crushing-malaxation process to obtain olive oil aroma. Both factors contribute independently to the content modification of C6, C5 compounds and esters in the olive oil aroma from stoned fruits.El deshuesado de la aceituna da lugar a una importante modificación del aroma del aceite de oliva virgen. La intensidad de esta modificación es característica de cada variedad. En los aceites obtenidos de aceitunas Verdial y Manzanilla se produce un incremento en el contenido de los compuestos de seis átomos de carbono (C6) que no se detecta en la variedad Picual. En las tres variedades estudiadas se observa un descenso del contenido de compuestos de cinco átomos de carbono (C5) así como del contenido en ésteres. En la variedad Verdial se ha comprobado que la modificación del aroma como consecuencia del deshuesado del fruto se debe tanto al daño tisular generado durante este proceso como a la ausencia de la semilla durante la molturación de la aceituna. Ambos factores contribuyen de forma independiente a la modificación del contenido de compuestos C6, C5 y ésteres en el aroma del aceite de oliva virgen procedente de aceituna deshuesada.El trabajo se ha realizado en el marco del Proyecto de Investigación AGL2002-02307 del Programa Nacional de Recursos y Tecnologías Agroalimentarias.Peer reviewe
Исследование характеристик ядерных трековых мембран для создания дренажной системы в лечении глаукомы
In this article has been researched possibility of using nuclear track membrane for fluid transport in the implementation and maintenance of the cornea weaklydehydrated state
Cognitive and emotional empathy in individuals at clinical high risk of psychosis
Background Impairments of social cognition are considered core features of schizophrenia and are established predictors of social functioning. However, affective aspects of social cognition including empathy have far less been studied than its cognitive dimensions. The role of empathy in the development of schizophrenia remains largely elusive. Methods Emotional and cognitive empathy were investigated in large sample of 120 individuals at Clinical High Risk of Psychosis (CHR-P) and compared with 50 patients with schizophrenia and 50 healthy controls. A behavioral empathy assessment, the Multifaceted Empathy Test, was implemented, and associations of empathy with cognition, social functioning, and symptoms were determined. Results Our findings demonstrated significant reductions of emotional empathy in individuals at CHR-P, while cognitive empathy appeared intact. Only individuals with schizophrenia showed significantly reduced scores of cognitive empathy compared to healthy controls and individuals at CHR-P. Individuals at CHR-P were characterized by significantly lower scores of emotional empathy and unspecific arousal for both positive and negative affective valences compared to matched healthy controls and patients with schizophrenia. Results also indicated a correlation of lower scores of emotional empathy and arousal with higher scores of prodromal symptoms. Conclusion Findings suggest that the tendency to 'feel with' an interaction partner is reduced in individuals at CHR-P. Altered emotional reactivity may represent an additional, early vulnerability marker, even if cognitive mentalizing is grossly unimpaired in the prodromal stage. Different mechanisms might contribute to reductions of cognitive and emotional empathy in different stages of non-affective psychotic disorders and should be further explored
Dopamine and Glutamate in Antipsychotic-Responsive Compared With Antipsychotic-Nonresponsive Psychosis: A Multicenter Positron Emission Tomography and Magnetic Resonance Spectroscopy Study (STRATA)
The variability in the response to antipsychotic medication in schizophrenia may reflect between-patient differences in neurobiology. Recent cross-sectional neuroimaging studies suggest that a poorer therapeutic response is associated with relatively normal striatal dopamine synthesis capacity but elevated anterior cingulate cortex (ACC) glutamate levels. We sought to test whether these measures can differentiate patients with psychosis who are antipsychotic responsive from those who are antipsychotic nonresponsive in a multicenter cross-sectional study. 1H-magnetic resonance spectroscopy (1H-MRS) was used to measure glutamate levels (Glucorr) in the ACC and in the right striatum in 92 patients across 4 sites (48 responders [R] and 44 nonresponders [NR]). In 54 patients at 2 sites (25 R and 29 NR), we additionally acquired 3,4-dihydroxy-6-[18F]fluoro-L-phenylalanine (18F-DOPA) positron emission tomography (PET) to index striatal dopamine function (Kicer, min−1). The mean ACC Glucorr was higher in the NR than the R group after adjustment for age and sex (F1,80 = 4.27; P = .04). This was associated with an area under the curve for the group discrimination of 0.59. There were no group differences in striatal dopamine function or striatal Glucorr. The results provide partial further support for a role of ACC glutamate, but not striatal dopamine synthesis, in determining the nature of the response to antipsychotic medication. The low discriminative accuracy might be improved in groups with greater clinical separation or increased in future studies that focus on the antipsychotic response at an earlier stage of the disorder and integrate other candidate predictive biomarkers. Greater harmonization of multicenter PET and 1H-MRS may also improve sensitivity
Human subcortical brain asymmetries in 15,847 people worldwide reveal effects of age and sex
The two hemispheres of the human brain differ functionally and structurally. Despite over a century of research, the extent to which brain asymmetry is influenced by sex, handedness, age, and genetic factors is still controversial. Here we present the largest ever analysis of subcortical brain asymmetries, in a harmonized multi-site study using meta-analysis methods. Volumetric asymmetry of seven subcortical structures was assessed in 15,847 MRI scans from 52 datasets worldwide. There were sex differences in the asymmetry of the globus pallidus and putamen. Heritability estimates, derived from 1170 subjects belonging to 71 extended pedigrees, revealed that additive genetic factors influenced the asymmetry of these two structures and that of the hippocampus and thalamus. Handedness had no detectable effect on subcortical asymmetries, even in this unprecedented sample size, but the asymmetry of the putamen varied with age. Genetic drivers of asymmetry in the hippocampus, thalamus and basal ganglia may affect variability in human cognition, including susceptibility to psychiatric disorders
Stereoscopic displays for air traffic control: conflict judgement performance as a function of visualisation, task characteristics and expertise
Three different stereoscopic 3D visualisations are compared with the 2D display currently used at air traffic control (ATC) controller working positions. Using safety critical air traffic scenarios, air traffic controllers (ATCOs), pilots, and two groups of laypersons, one of which with appropriate training, are asked to judge safety critical scenarios showing two converging aircraft. To simulate the cognitive demands ATCOs have to face when required to process both visual information of the traffic situation display and auditory information caused by incoming radio messages at the same time, an auditory task is added. Due to the experimental manipulation of visualisation-, task-, and person-related variables, the results allow for an explanation of the inconsistent results that have been reported in studies evaluating the use of 3D for ATC. Analyses reveal that performance differences between 2D and 3D depend on both task characteristics and the level of expertise. While the judgement certainty of 2D and 3D is virtually equal in all cases of conflict, the observed differences between the modes of visualisation appear to be due to the dimension on which the aircraft miss each other in case of separation. When judgement certainty is ignored, no noteworthy differences appear. Thus, the results depend on the individual response criterion, because it represents the level of uncertainty the operator is willing to accept
Effects of antidopaminergic intervention on catecholamine metabolites in plasma and urine in healthy volunteers
St. John's Daily Star, 1920-11-20
The St. John's Daily Star was published daily except Sunday between 17 April 1915 - 23 July 1921
Simulation-based partial volume correction for dopaminergic PET imaging: Impact of segmentation accuracy
AimPartial volume correction (PVC) is an essential step for quantitative positron emission tomography (PET). In the present study, PVELab, a freely available software, is evaluated for PVC in 18F-FDOPA brain-PET, with a special focus on the accuracy degradation introduced by various MR-based segmentation approaches.MethodsFour PVC algorithms (M-PVC; MG-PVC; mMG-PVC; and R-PVC) were analyzed on simulated 18F-FDOPA brain-PET images. MR image segmentation was carried out using FSL (FMRIB Software Library) and SPM (Statistical Parametric Mapping) packages, including additional adaptation for subcortical regions (SPML). Different PVC and segmentation combinations were compared with respect to deviations in regional activity values and time-activity curves (TACs) of the occipital cortex (OCC), caudate nucleus (CN), and putamen (PUT). Additionally, the PVC impact on the determination of the influx constant (Ki) was assessed.ResultsMain differences between tissue-maps returned by three segmentation algorithms were found in the subcortical region, especially at PUT. Average misclassification errors in combination with volume reduction was found to be lowest for SPML (PUT 70%). Accurate recovery of activity data at OCC is achieved by M-PVC (apparent recovery coefficient varies between 0.99 and 1.10). The other three evaluated PVC algorithms have demonstrated to be more suitable for subcortical regions with MG-PVC and mMG-PVC being less prone to the largest tissue misclassification error simulated in this study. Except for M-PVC, quantification accuracy of Ki for CN and PUT was clearly improved by PVC.ConclusionsThe regional activity value of PUT was appreciably overcorrected by most of the PVC approaches employing FSL or SPM segmentation, revealing the importance of accurate MR image segmentation for the presented PVC framework. The selection of a PVC approach should be adapted to the anatomical structure of interest. Caution is recommended in subsequent interpretation of Ki values. The possible different change of activity concentrations due to PVC in both target and reference regions tends to alter the corresponding TACs, introducing bias to Ki determination. The accuracy of quantitative analysis was improved by PVC but at the expense of precision reduction, indicating the potential impropriety of applying the presented framework for group comparison studies
Elevated [(18)F]FDOPA utilization in the periaqueductal gray and medial nucleus accumbens of patients with early Parkinson's disease
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