120 research outputs found

    Neurophysiological Responses to Different Product Experiences

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    It is well known that the evaluation of a product from the shelf considers the simultaneous cerebral and emotional evaluation of the different qualities of the product such as its colour, the eventual images shown, and the envelope’s texture (hereafter all included in the term “product experience”). However, the measurement of cerebral and emotional reactions during the interaction with food products has not been investigated in depth in specialized literature. (e aim of this paper was to investigate such reactions by the EEG and the autonomic activities, as elicited by the cross-sensory interaction (sight and touch) across several different products. In addition, we investigated whether (i) the brand (Major Brand or Private Label), (ii) the familiarity (Foreign or Local Brand), and (iii) the hedonic value of products (Comfort Food or Daily Food) influenced the reaction of a group of volunteers during their interaction with the products. Results showed statistically significantly higher tendency of cerebral approach (as indexed by EEG frontal alpha asymmetry) in response to comfort food during the visual exploration and the visual and tactile exploration phases. Furthermore, for the same index, a higher tendency of approach has been found toward foreign food products in comparison with local food products during the visual and tactile exploration phase. Finally, the same comparison performed on a different index (EEG frontal theta) showed higher mental effort during the interaction with foreign products during the visual exploration and the visual and tactile exploration phases. Results from the present study could deepen the knowledge on the neurophysiological response to food products characterized by different nature in terms of hedonic value familiarity; moreover, they could have implications for food marketers and finally lead to further study on how people make food choices through the interactions with their commercial envelope

    Wide cross-reactivity between Anopheles gambiae and Anopheles funestus SG6 salivary proteins supports exploitation of gSG6 as a marker of human exposure to major malaria vectors in tropical Africa

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    <p>Abstract</p> <p>Background</p> <p>The <it>Anopheles gambiae </it>gSG6 is an anopheline-specific salivary protein which helps female mosquitoes to efficiently feed on blood. Besides its role in haematophagy, gSG6 is immunogenic and elicits in exposed individuals an IgG response, which may be used as indicator of exposure to the main African malaria vector <it>A. gambiae</it>. However, malaria transmission in tropical Africa is sustained by three main vectors (<it>A. gambiae</it>, <it>Anopheles arabiensis </it>and <it>Anopheles funestus</it>) and a general marker, reflecting exposure to at least these three species, would be especially valuable. The SG6 protein is highly conserved within the <it>A. gambiae </it>species complex whereas the <it>A. funestus </it>homologue, fSG6, is more divergent (80% identity with gSG6). The aim of this study was to evaluate cross-reactivity of human sera to gSG6 and fSG6.</p> <p>Methods</p> <p>The <it>A. funestus </it>SG6 protein was expressed/purified and the humoral response to gSG6, fSG6 and a combination of the two antigens was compared in a population from a malaria hyperendemic area of Burkina Faso where both vectors were present, although with a large <it>A. gambiae </it>prevalence (>75%). Sera collected at the beginning and at the end of the high transmission/rainy season, as well as during the following low transmission/dry season, were analysed.</p> <p>Results</p> <p>According to previous observations, both anti-SG6 IgG level and prevalence decreased during the low transmission/dry season and showed a typical age-dependent pattern. No significant difference in the response to the two antigens was found, although their combined use yielded in most cases higher IgG level.</p> <p>Conclusions</p> <p>Comparative analysis of gSG6 and fSG6 immunogenicity to humans suggests the occurrence of a wide cross-reactivity, even though the two proteins carry species-specific epitopes. This study supports the use of gSG6 as reliable indicator of exposure to the three main African malaria vectors, a marker which may be useful to monitor malaria transmission and evaluate vector control measures, especially in conditions of low malaria transmission and/or reduced vector density. The <it>Anopheles stephensi </it>SG6 protein also shares 80% identity with gSG6, suggesting the attractive possibility that the <it>A. gambiae </it>protein may also be useful to assess human exposure to several Asian malaria vectors.</p

    Brain Response to Antismoking PSA, an EEG Study

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    Public service antismoke announcements (PSA) are essential tools for promoting messages worthy of society. In 2015 the Italian Government released an anti-smoking PSA to raise young people’s awareness of the smoking dangers. To demonstrate the effectiveness of that campaign, the present study investigated the mental response of 56 participants while watching the PSA through the Electroencephalogram (EEG). The EEG is frequently employed in neuromarketing to face the limitations of verbal declarations, allowing to evaluate the advertisings’ efficacy objectively. The present study analyzed the PSA, considering the smoking habit of participants by dividing them into smokers and nonsmokers. Some main segments of the PSA were identified and separately analyzed for evidencing the most effective part for the anti-smoking message. Three main EEG indexes have been explored in the analysis: mental engagement index (ME), spectral asymmetry index (SASI), and the mental effort index. The t-test performed on the index values showed an increase of the ME and the SASI for smokers compared to non-smokers (p&lt;0.005). While the repeated measures ANOVA pointed out that the indexes were differently modulated by the parts of the PSA, showing the effectiveness of the smoking symptoms’ description and the claim at the brain level

    Neurophysiological characterization of normal hearing and unilateral hearing loss children: a comparison among EEG-based indices for information processing and decision-making levels.

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    The identification of measurable indices of cerebral functions to be applied in clinical settings is ever more felt as necessary for a more thorough and objective evaluation of patients cognitive performance. In the present paper, the electroencephalographic-based indices of mental workload (WL = frontal θ/parietal α) and of mental engagement (ME = β/(α+θ)), calculated along the brain midline, have been employed to characterize the eventual specific patterns of cerebral activations during a speech in noise perception task in normal hearing (NH) and unilateral hearing loss (UHL) children. Results showed no differences between the groups for the frontal bilateral noise condition (in which both signal and noise were emitted by two loudspeakers placed +45° and -45° in relation to the participant), while in lateralized noise conditions the UHL group showed higher parietal ME values for the Noise to the Deaf Ear condition). Finally, the NH group showed a different distribution of ME values among frontal, central and parietal electrodes, with higher ME values in the central and parietal ones in correspondence of the Noise to the Left Ear condition. The WL index analysis did not provide any significant differences. Results suggest the relevance of including the analysis of the beta rhythm in the neurophysiological assessment of the neural processing of speech in noise stimuli in normal hearing and hearing impaired participants

    Neurophysiological assessment of an innovative maritime safety system in terms of ship operators' mental workload, stress, and attention in the full mission bridge simulator

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    The current industrial environment relies heavily on maritime transportation. Despite the continuous technological advances for the development of innovative safety software and hardware systems, there is a consistent gap in the scientific literature regarding the objective evaluation of the performance of maritime operators. The human factor is profoundly affected by changes in human performance or psychological state. The difficulty lies in the fact that the technology, tools, and protocols for investigating human performance are not fully mature or suitable for experimental investigation. The present research aims to integrate these two concepts by (i) objectively characterizing the psychological state of mariners, i.e., mental workload, stress, and attention, through their electroencephalographic (EEG) signal analysis, and (ii) validating an innovative safety framework countermeasure, defined as Human Risk-Informed Design (HURID), through the aforementioned neurophysiological approach. The proposed study involved 26 mariners within a high-fidelity bridge simulator while encountering collision risk in congested waters with and without the HURID. Subjective, behavioral, and neurophysiological data, i.e., EEG, were collected throughout the experimental activities. The results showed that the participants experienced a statistically significant higher mental workload and stress while performing the maritime activities without the HURID, while their attention level was statistically lower compared to the condition in which they performed the experiments with the HURID (all p < 0.05). Therefore, the presented study confirmed the effectiveness of the HURID during maritime operations in critical scenarios and led the way to extend the neurophysiological evaluation of the HFs of maritime operators during the performance of critical and/or standard shipboard tasks

    Humoral Response to the Anopheles gambiae Salivary Protein gSG6: A Serological Indicator of Exposure to Afrotropical Malaria Vectors

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    Salivary proteins injected by blood feeding arthropods into their hosts evoke a saliva-specific humoral response which can be useful to evaluate exposure to bites of disease vectors. However, saliva of hematophagous arthropods is a complex cocktail of bioactive factors and its use in immunoassays can be misleading because of potential cross-reactivity to other antigens. Toward the development of a serological marker of exposure to Afrotropical malaria vectors we expressed the Anopheles gambiae gSG6, a small anopheline-specific salivary protein, and we measured the anti-gSG6 IgG response in individuals from a malaria hyperendemic area of Burkina Faso, West Africa. The gSG6 protein was immunogenic and anti-gSG6 IgG levels and/or prevalence increased in exposed individuals during the malaria transmission/rainy season. Moreover, this response dropped during the intervening low transmission/dry season, suggesting it is sensitive enough to detect variation in vector density. Members of the Fulani ethnic group showed higher anti-gSG6 IgG response as compared to Mossi, a result consistent with the stronger immune reactivity reported in this group. Remarkably, anti-gSG6 IgG levels among responders were high in children and gradually declined with age. This unusual pattern, opposite to the one observed with Plasmodium antigens, is compatible with a progressive desensitization to mosquito saliva and may be linked to the continued exposure to bites of anopheline mosquitoes. Overall, the humoral anti-gSG6 IgG response appears a reliable serological indicator of exposure to bites of the main African malaria vectors (An. gambiae, Anopheles arabiensis and, possibly, Anopheles funestus) and it may be exploited for malaria epidemiological studies, development of risk maps and evaluation of anti-vector measures. In addition, the gSG6 protein may represent a powerful model system to get a deeper understanding of molecular and cellular mechanisms underlying the immune tolerance and progressive desensitization to insect salivary allergens

    Serum Albumin Is Inversely Associated With Portal Vein Thrombosis in Cirrhosis

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    We analyzed whether serum albumin is independently associated with portal vein thrombosis (PVT) in liver cirrhosis (LC) and if a biologic plausibility exists. This study was divided into three parts. In part 1 (retrospective analysis), 753 consecutive patients with LC with ultrasound-detected PVT were retrospectively analyzed. In part 2, 112 patients with LC and 56 matched controls were entered in the cross-sectional study. In part 3, 5 patients with cirrhosis were entered in the in vivo study and 4 healthy subjects (HSs) were entered in the in vitro study to explore if albumin may affect platelet activation by modulating oxidative stress. In the 753 patients with LC, the prevalence of PVT was 16.7%; logistic analysis showed that only age (odds ratio [OR], 1.024; P = 0.012) and serum albumin (OR, -0.422; P = 0.0001) significantly predicted patients with PVT. Analyzing the 112 patients with LC and controls, soluble clusters of differentiation (CD)40-ligand (P = 0.0238), soluble Nox2-derived peptide (sNox2-dp; P &lt; 0.0001), and urinary excretion of isoprostanes (P = 0.0078) were higher in patients with LC. In LC, albumin was correlated with sCD4OL (Spearman's rank correlation coefficient [r(s)], -0.33; P &lt; 0.001), sNox2-dp (r(s), -0.57; P &lt; 0.0001), and urinary excretion of isoprostanes (r(s), -0.48; P &lt; 0.0001) levels. The in vivo study showed a progressive decrease in platelet aggregation, sNox2-dp, and urinary 8-iso prostaglandin F2 alpha-III formation 2 hours and 3 days after albumin infusion. Finally, platelet aggregation, sNox2-dp, and isoprostane formation significantly decreased in platelets from HSs incubated with scalar concentrations of albumin. Conclusion: Low serum albumin in LC is associated with PVT, suggesting that albumin could be a modulator of the hemostatic system through interference with mechanisms regulating platelet activation
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