909 resultados para sensory perception and cognition


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Selostus: Taikinaan lisättyjen gluteenin ja transglutaminaasin vaikutus kauraleivän rakenteeseen

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Homozygosity has long been associated with rare, often devastating, Mendelian disorders, and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness. However, the effect of the more distant parental relatedness that is common in modern human populations is less well understood. Genomic data now allow us to investigate the effects of homozygosity on traits of public health importance by observing contiguous homozygous segments (runs of homozygosity), which are inferred to be homozygous along their complete length. Given the low levels of genome-wide homozygosity prevalent in most human populations, information is required on very large numbers of people to provide sufficient power. Here we use runs of homozygosity to study 16 health-related quantitative traits in 354,224 individuals from 102 cohorts, and find statistically significant associations between summed runs of homozygosity and four complex traits: height, forced expiratory lung volume in one second, general cognitive ability and educational attainment (P < 1 × 10(-300), 2.1 × 10(-6), 2.5 × 10(-10) and 1.8 × 10(-10), respectively). In each case, increased homozygosity was associated with decreased trait value, equivalent to the offspring of first cousins being 1.2 cm shorter and having 10 months' less education. Similar effect sizes were found across four continental groups and populations with different degrees of genome-wide homozygosity, providing evidence that homozygosity, rather than confounding, directly contributes to phenotypic variance. Contrary to earlier reports in substantially smaller samples, no evidence was seen of an influence of genome-wide homozygosity on blood pressure and low density lipoprotein cholesterol, or ten other cardio-metabolic traits. Since directional dominance is predicted for traits under directional evolutionary selection, this study provides evidence that increased stature and cognitive function have been positively selected in human evolution, whereas many important risk factors for late-onset complex diseases may not have been.

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Using data from free listings and a survey in two villages of Tamil Nadu, India, we discuss local perceptions and uses of water tanks, a traditional irrigation infrastructure. We hypothesize that both farmers and nonfarmers perceive and use water tanks for purposes other than irrigation. We found that informants recognized the importance of water tanks for irrigation, but also acknowledged other socioeconomic uses and ecological functions. Marginal sectors (i.e., Scheduled Castes) use tank resources in more diverse ways than other sectors of the population. Findings are relevant for development. International organizations working on the revival of water tanks aim to transfer water management to farmers for the purpose of irrigation. By recognizing that tanks benefit people other than farmers and in ways other than providing irrigation water, organizations working on tank rejuvenation could achieve a more equitable management of tank resources.

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Background: Insects respond to the spatial and temporal dynamics of a pheromone plume, which implies not only a strong response to"odor on", but also to"odor off". This requires mechanisms geared toward a fast signal termination. Several mechanisms may contribute to signal termination, among which odorant-degrading enzymes. These enzymes putatively play a role in signal dynamics by a rapid inactivation of odorants in the vicinity of the sensory receptors, although direct in vivo experimental evidences are lacking. Here we verified the role of an extracellular carboxylesterase, esterase-6 (Est-6), in the sensory physiological and behavioral dynamics of Drosophila melanogaster response to its pheromone, cis-vaccenyl acetate (cVA). Est-6 was previously linked to post-mating effects in the reproductive system of females. As Est-6 is also known to hydrolyze cVA in vitro and is expressed in the main olfactory organ, the antenna, we tested here its role in olfaction as a putative odorant-degrading enzyme. Results: We first confirm that Est-6 is highly expressed in olfactory sensilla, including cVA-sensitive sensilla, and we show that expression is likely associated with non-neuronal cells. Our electrophysiological approaches show that the dynamics of olfactory receptor neuron (ORN) responses is strongly influenced by Est-6, as in Est-6° null mutants (lacking the Est-6 gene) cVA-sensitive ORN showed increased firing rate and prolonged activity in response to cVA. Est-6° mutant males had a lower threshold of behavioral response to cVA, as revealed by the analysis of two cVAinduced behaviors. In particular, mutant males exhibited a strong decrease of male-male courtship, in association with a delay in courtship initiation. Conclusions: Our study presents evidence that Est-6 plays a role in the physiological and behavioral dynamics of sex pheromone response in Drosophila males and supports a role of Est-6 as an odorant-degrading enzyme (ODE) in male antennae. Our results also expand the role of Est-6 in Drosophila biology, from reproduction to olfaction, and highlight the role of ODEs in insect olfaction. Keywords: carboxylesterase, esterase 6, olfaction, pheromone, signal termination

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The purpose of this descriptive survey was to investigate the risk perceptions of smoking in a sample of 1,510 Spanish adolescents(49.1% males; mean age = 14.03; SD = 1.28). In addition, the present research categorised adolescents into one of the fourstages of smoking acquisition, as described by the Transtheoretical Model of Change (TMC): Precontemplation (notthinking about trying smoking in the next 6 months), Contemplation (thinking about trying smoking in the next 6 months), Preparation (thinking about starting smoking in the next 30 days) and Action (smokers), by gender and age. The results showed that age and risk perceptions are important variables in the progression through the stages of change towards regular tobacco consumption (Action stage). These results clearly demonstrate the importance of starting antismoking campaigns at an early age to prevent smoking acquisition or the thought of starting in the near future. These findings also highlight the need to continuously remind adolescents about the negative consequences of smoking

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I mars 2003 certifierades en finländsk advokatbyrå av den Europeiska kommissionen som den bästa i Europa inom specialkategorin livslångt lärande. Advokatbyrån var överraskad över utnämningen emedan de inte aktivt och/eller medvetet implementerat eller utövat en livslångt lärandestrategi i sin verksamhet bland sin personal. Byrån deltog i en tävling om bästa arbetsplats i Europa ("Best workplaces in Europe 2003") utan att vara medveten om den Europeiska kommissionens special- kategorier. Emedan advokatbyrån inte medvetet implementerat en livslångt lärandestrategi bland sin personal formar aktörerna, vars uppfattning och prat denna avhandling handlar om, sina föreställningar och sitt prat om livslångt lärande efter utnämningen. Översättningsprocessen av en idé utlöses sålunda i denna studie av en extern händelse. I sin avhandling beskriver Annica Isacsson hur och varför en idé (livslångt lärande) föds (på nytt) på en institutionell nivå, hur idén reser och förändras i en process av översättning, hur idén landar i två organisationer samt hur idén om livslångt lärande uppfattas och beskrivs av lokala aktörer i två olika organisationer. Fokus i studien ligger sålunda på enskilda aktörers uppfattning om ett kontroversiellt koncept i en lokal kontext. Teoretiskt möts och sammanlänkas teori om livslångt lärande, sociokulturella teorier om lärande och teorier om organisatoriskt lärande. Isacssons avhandling visar på hur livslångt lärande inte enbart, i en organisatorisk kontext, handlar om individuell kompetensutveckling utan också om organisatoriskt lärande i vilken lärande av andra organisationsmedlemmar och organisationer ingår. Studien visar vidare på hur enskilda aktörers prat påverkas av det institutionella fältet och av den tidsanda inom vilken diskursen livslångt lärande föds, rör sig och ingår.

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Background: Eating disorders are serious psychiatric disorders, which usually have their onset in adolescence. Body dissatisfaction and dieting, both common among adolescents, are recognised risk factors for eating disorders. The aim of the present study was to assess the prevalence of eating disorders in the general adolescent population, assess the risk of developing eating disorders in subgroups of dieters, and analyse longitudinal concomitants of incorrect weight perception. Method: A prospective follow-up study on 595 adolescents, aged 15 at baseline, was conducted in western Finland. The study comprised questionnaires directed at the whole study population and subsequent personal interviews with adolescents found to be screen-positive for eating disorders, at both baseline and three-year follow-up. Results: The lifetime prevalence rates for 18 year old females were 2.6 % for anorexia nervosa, 0.4 for bulimia nervosa, and 9.0 % for eating disorder not otherwise specified (EDNOS). No prevalent case of DSM-IV eating disorders was found among the male participants. Eating disorders, as well as depressive symptoms, social anxiety, and low self-esteem, was more prevalent among females who perceived themselves as being overweight, despite being normal or underweight, when compared to females with a correct weight perception. An incorrect weight perception was associated in males with social anxiety. Female adolescents dieting due to psychological distress, rather than vanity or overweight, had a fifteen-fold risk of developing an eating disorder. Conclusions: Eating disorders are common among female adolescents, and adolescents choosing to diet due to psychological distress show a markedly increased risk of developing an eating disorder. Promotion of general well-being as well as the prevention of body dissatisfaction and misdirected dieting, accompanied by early detection and proper treatment of eating disorders, is needed to reduce the incidence of and facilitate recovery in adolescents suffering from eating disorders.

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The rate of axonal regeneration, after sciatic nerve lesion in adult C57BL/6J mice, is reduced when compared to other isogenic strains. It was observed that such low regeneration was not due just to a delay, since neuronal death was observed. Two general mechanisms of cell death, apoptosis and necrosis, may be involved. By using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) technique, we demonstrated that a large number of sensory neurons, as well as satellite cells found in the dorsal root ganglia, were intensely labeled, thus indicating that apoptotic mechanisms were involved in the death process. Although almost no labeled neurons or satellite cells were observed one week after transection, a more than ten-fold increase in TUNEL labeling was detected after two weeks. The results obtained with the C57BL/6J strain were compared with those of the A/J strain, which has a much higher peripheral nerve regeneration potential. In A/J mice, almost no labeling of sensory neurons or satellite cells was observed after one or two weeks, indicating the absence of neuronal loss. Our data confirm previous observations that approximately 40% of C57BL/6J sensory neurons die after sciatic nerve transection, and indicate that apoptotic events are involved. Also, our observations reinforce the hypothesis that the low rate of axonal regeneration occurring in C57BL/6J mice may be the result of a mismatch in the timing of the neurons need for neurotrophic substances, and production of the latter by non-neuronal cells in the distal stump.

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Molecular oxygen (O2) is the premier biological electron acceptor that serves vital roles in fundamental cellular functions. However, with the beneficial properties of O2 comes the inadvertent formation of reactive oxygen species (ROS) such as superoxide (O2·-), hydrogen peroxide, and hydroxyl radical (OH·). If unabated, ROS pose a serious threat to or cause the death of aerobic cells. To minimize the damaging effects of ROS, aerobic organisms evolved non-enzymatic and enzymatic antioxidant defenses. The latter include catalases, peroxidases, superoxide dismutases, and glutathione S-transferases (GST). Cellular ROS-sensing mechanisms are not well understood, but a number of transcription factors that regulate the expression of antioxidant genes are well characterized in prokaryotes and in yeast. In higher eukaryotes, oxidative stress responses are more complex and modulated by several regulators. In mammalian systems, two classes of transcription factors, nuclear factor kB and activator protein-1, are involved in the oxidative stress response. Antioxidant-specific gene induction, involved in xenobiotic metabolism, is mediated by the "antioxidant responsive element" (ARE) commonly found in the promoter region of such genes. ARE is present in mammalian GST, metallothioneine-I and MnSod genes, but has not been found in plant Gst genes. However, ARE is present in the promoter region of the three maize catalase (Cat) genes. In plants, ROS have been implicated in the damaging effects of various environmental stress conditions. Many plant defense genes are activated in response to these conditions, including the three maize Cat and some of the superoxide dismutase (Sod) genes.

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Questions concerning perception are as old as the field of philosophy itself. Using the first-person perspective as a starting point and philosophical documents, the study examines the relationship between knowledge and perception. The problem is that of how one knows what one immediately perceives. The everyday belief that an object of perception is known to be a material object on grounds of perception is demonstrated as unreliable. It is possible that directly perceived sensible particulars are mind-internal images, shapes, sounds, touches, tastes and smells. According to the appearance/reality distinction, the world of perception is the apparent realm, not the real external world. However, the distinction does not necessarily refute the existence of the external world. We have a causal connection with the external world via mind-internal particulars, and therefore we have indirect knowledge about the external world through perceptual experience. The research especially concerns the reasons for George Berkeley’s claim that material things are mind-dependent ideas that really are perceived. The necessity of a perceiver’s own qualities for perceptual experience, such as mind, consciousness, and the brain, supports the causal theory of perception. Finally, it is asked why mind-internal entities are present when perceiving an object. Perception would not directly discern material objects without the presupposition of extra entities located between a perceiver and the external world. Nevertheless, the results show that perception is not sufficient to know what a perceptual object is, and that the existence of appearances is necessary to know that the external world is being perceived. However, the impossibility of matter does not follow from Berkeley’s theory. The main result of the research is that singular knowledge claims about the external world never refer directly and immediately to the objects of the external world. A perceiver’s own qualities affect how perceptual objects appear in a perceptual situation.

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The objective of this study was to evaluate the nutritional value, the oxidative stabilitiy, and consumer acceptance of cakes containing four different concentrations of flaxseed flour (5, 15, 30 and 45%) as partial replacement for wheat flour. The oxidative stability of polyunsaturated fatty acids was evaluated through the lipid peroxidation test (TBARS) in the flour and cakes. Linolenic acid was determined by gas chromatography as well as contents of protein, lipid, ash, and dietary fiber. Consumer acceptance was assessed using a structured hedonic scale of nine points. The oxidative stability of lipid flaxseeds was not affected by the heat treatment during flour processing and cake baking. Cakes made with 5, 15, and 30% of flaxseed flour, the most accepted by consumers, had dietary fiber levels ranging from 3.5 to 6.2 g and linolenic acid ranging from 445 to 2,500 mg.100 g-1 of the product. The cakes received claims of good and excellent source of dietary fiber and linolenic acid, respectively, both are bioactive compounds. The use of up to 30% of flaxseed flour in the preparation of cakes is a useful strategy to optimize the consumption of food rich in functional ingredients.

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The aim of this study was to use a factorial design approach for developing a palatable and stable soy-based dessert with the addition of Soy Protein (SP), oligofructose, and Passion Fruit Juice (PFJ). Panelists (n = 50) used a seven-point hedonic scale to assess the overall liking, degree of liking of creaminess, taste, and color of the desserts. In addition, the samples were submitted to a preference ranking test in order to evaluate the products' preference. Water Holding Capacity (WHC) and backscattering (BS) measures were also determined to assess the physical stability of the trials. Sample F3 (35% PFJ and 2% SP) was the only one that presented a WHC index of 94.8%; moreover, none of the developed samples had synerisis after 72 hours of storage indicating adequate physical stability of the emulsion process. Samples F2 (25% PFJ, and 3.0% SP), F4 (35% PFJ, and 3.0% SP), and F5 (30% PFJ, and 2.5% SP) presented mean hedonic scores above 'slightly liked' for all sensory attributes. The acceptance index of samples varied from 62.50 to 88% showing the great sensory potential of such products.

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Decreased gustatory and olfactory capacity is one of the problems caused by tobacco use. The objectives of this study were to determine the sensory profile of six grape nectar samples sweetened with different sweeteners and to verify the drivers of liking in two distinct consumer groups: smokers and nonsmokers. The sensory profile was constructed by twelve trained panelists using quantitative descriptive analysis (QDA). Consumer tests were performed with 112 smokers and 112 nonsmokers. Partial least squares regression analyses was used to identify the drivers of acceptance and rejection of the grape nectars among the two consumer groups. According to the QDA, the samples differed regarding six of the nineteen attributes generated. The absolute averages of the affective test were lower in the group of smokers; possibly because smoking influences acceptance and eating preferences, especially with regard to sweet foods. The results showed that the grape flavor was the major driver of preference for acceptance of the nectar, while astringency, wine aroma, bitterness and sweetness, and bitter aftertaste were drivers of rejection in the two groups of consumers, with some differences between the groups.

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Yacon is considered a functional food due to its the fructooligosaccharide (FOS) content, however its perishability and low production volume is a problem. The aim of this study was to analyze the changes in aging during one year of storage and conduct sensory analysis of fermented of yacon. For one year total acidity, volatile acidity, free and total sulfur dioxide, reducing sugars, sucrose, phenols and FOS and its antioxidant power were studied. At the end of aging a sensory profile and acceptance panel was performed. The total and volatile acidity increased significantly (p < 0.05). A decrease in fructooligosaccharide was also observed, indicating that yeasts are probably capable of hydrolyzing the latter. The total sulfur dioxide decreased significantly, demonstrating its ability to act well against oxidation products. This product showed good antioxidant capacity and sensory profiles of considerable acceptance. Therefore it can be affirmed that the alcoholic fermentation of yacon can be a good alternative for the industrial sector and farmers in the region could be encouraged to use large-scale production.