Science.gov

Sample records for odour perception recognition

  1. Characterisation of human behaviour during odour perception.

    PubMed

    Laing, D G

    1982-01-01

    Factors which govern the optimum perception of odours have not yet been defined. This has hindered the development of standard methods and instruments for measuring olfactory responses. As an initial step towards defining these conditions, inhalation rates and volumes, number of sniffs, and sniff duration were measured for twenty-three humans in odour-threshold and odour-intensity tests with pentyl acetate, 1-butanol, and diethylamine. Measurements were made with the aid of a hot-wire anemometer concealed within the outlet of an air-dilution olfactometer. Individuals varied markedly in their sampling techniques but maintained their characteristic sniffing patterns with different odours and olfactory tasks. Only three parameters consistently varied with odour concentration: total volume of odour sampled, total sampling time, and number of sniffs. Maximum inhalation rate was remarkably stable and was independent of the type, concentration, and pleasantness of odour. Values recorded for sniff volumes and inhalation rates indicate that most olfactometers in use do not accommodate human inhalation requirements during a sniffing episode. The many common characteristics in the varied sampling techniques of different subjects suggest that the techniques are close to those providing optimum odour perception. Whether these are inherited or developed through habit or experience is not known. PMID:7155775

  2. Natural sniffing gives optimum odour perception for humans.

    PubMed

    Laing, D G

    1983-01-01

    The characteristics of human sniffing episodes during odour perception have been described in an earlier paper, where it has been suggested that the techniques used by individuals may be close to those providing optimum perception. To investigate this suggestion, threshold and intensity tests with butanol, cyclohexanone, and pentyl acetate have been carried out on twenty-one subjects. Olfactory responses obtained by using natural sniffing techniques were compared with those where the number of sniffs, interval between sniffs, and size of sniffs were varied. The results indicate that it is very difficult to improve on the efficiency of sniffing techniques of individuals and that a single natural sniff provides as much information about the presence and intensity of an odour as do seven or more sniffs. A single natural sniff and the first sniff of a a natural sniffing episode were shown to have similar characteristics and most significantly both were unaffected by changes in the concentration and type of odour. Overall, the results indicate that humans achieve optimum odour perception during threshold and intensity measures with their natural multiple-sniff technique or with a single sniff. For the 'average' human this occurs with a sniff of inhalation rate 30 1 min-1, volume 200 cm3, and duration 0.4 s. The use of several sniffs in a sniffing episode appears to be a confirmatory action rather than a necessary one, except for the perception of odour mixtures where several sniffs are likely to be needed to aid discrimination of the components. Data from the present and earlier study provide the information necessary for the development of a standard olfactometer and standard procedures for measuring the olfactory responses of humans. PMID:6657430

  3. Not one odour but two: A new model for nestmate recognition.

    PubMed

    Newey, Philip

    2011-02-01

    Recognition systems play a key role in a range of biological processes, including mate choice, immune defence and altruistic behaviour. Social insects provide an excellent model for studying recognition systems because workers need to discriminate between nestmates and non-nestmates, enabling them to direct altruistic behaviour towards closer kin and to repel potential invaders. However, the level of aggression directed towards conspecific intruders can vary enormously, even among workers within the same colony. This is usually attributed to differences in the aggression thresholds of individuals or to workers having different roles within the colony. Recent evidence from the weaver ant Oecophylla smaragdina suggests that this does not tell the whole story. Here I propose a new model for nestmate recognition based on a vector template derived from both the individual's innate odour and the shared colony odour. This model accounts for the recent findings concerning weaver ants, and also provides an alternative explanation for why the level of aggression expressed by a colony decreases as the diversity within the colony increases, even when odour is well-mixed. The model makes additional predictions that are easily tested, and represents a significant advance in our conceptualisation of recognition systems.

  4. Public perception of odour and environmental pollution attributed to MSW treatment and disposal facilities: A case study

    SciTech Connect

    De Feo, Giovanni; De Gisi, Sabino; Williams, Ian D.

    2013-04-15

    Highlights: ► Effects of closing MSW facilities on perception of odour and pollution studied. ► Residents’ perception of odour nuisance considerably diminished post closure. ► Odour perception showed an association with distance from MSW facilities. ► Media coverage increased knowledge about MSW facilities and how they operate. ► Economic compensation possibly affected residents’ views and concerns. - Abstract: If residents’ perceptions, concerns and attitudes towards waste management facilities are either not well understood or underestimated, people can produce strong opposition that may include protest demonstrations and violent conflicts such as those experienced in the Campania Region of Italy. The aim of this study was to verify the effects of the closure of solid waste treatment and disposal facilities (two landfills and one RDF production plant) on public perception of odour and environmental pollution. The study took place in four villages in Southern Italy. Identical questionnaires were administered to residents during 2003 and after the closure of the facilities occurred in 2008. The residents’ perception of odour nuisance considerably diminished between 2003 and 2009 for the nearest villages, with odour perception showing an association with distance from the facilities. Post closure, residents had difficulty in identifying the type of smell due to the decrease in odour level. During both surveys, older residents reported most concern about the potentially adverse health impacts of long-term exposure to odours from MSW facilities. However, although awareness of MSW facilities and concern about potentially adverse health impacts varied according to the characteristics of residents in 2003, substantial media coverage produced an equalisation effect and increased knowledge about the type of facilities and how they operated. It is possible that residents of the village nearest to the facilities reported lower awareness of and concern about

  5. Evidence for nest-odour recognition in two species of diving petrel.

    PubMed

    Bonadonna, Francesco; Cunningham, Gregory B; Jouventin, Pierre; Hesters, Florence; Nevitt, Gabrielle A

    2003-10-01

    In nearly every procellariiform species, the sense of smell appears to be highly adapted for foraging at sea, but the sense of smell among the diving petrels is enigmatic. These birds forage at considerable depth and are not attracted to odour cues at sea. However, several procellariiform species have recently been shown to relocate their nesting burrows by scent, suggesting that these birds use an olfactory signature to identify the home burrow. We wanted to know whether diving petrels use smell in this way. We tested the common diving petrel Pelecanoides urinatrix and the South-Georgian diving petrel Pelecanoides georgicus to determine whether diving petrels were able to recognise their burrow by scent alone. To verify the efficacy of the method, we also tested a bird that is known to use olfaction for foraging and nest recognition, the thin-billed prion Pachyptila belcheri. In two-choice T-maze trials, we found that, for all species, individuals significantly preferred the odour of their own nest material to that of a conspecific. Our findings strongly suggest that an individual-specific odour provides an olfactory signature that allows burrowing petrels to recognize their own burrow. Since this ability seems to be well developed in diving petrels, our data further implicate a novel adaptation for olfaction in these two species that have been presumed to lack a well-developed sense of smell. PMID:12966063

  6. Public perception of odour and environmental pollution attributed to MSW treatment and disposal facilities: a case study.

    PubMed

    De Feo, Giovanni; De Gisi, Sabino; Williams, Ian D

    2013-04-01

    If residents' perceptions, concerns and attitudes towards waste management facilities are either not well understood or underestimated, people can produce strong opposition that may include protest demonstrations and violent conflicts such as those experienced in the Campania Region of Italy. The aim of this study was to verify the effects of the closure of solid waste treatment and disposal facilities (two landfills and one RDF production plant) on public perception of odour and environmental pollution. The study took place in four villages in Southern Italy. Identical questionnaires were administered to residents during 2003 and after the closure of the facilities occurred in 2008. The residents' perception of odour nuisance considerably diminished between 2003 and 2009 for the nearest villages, with odour perception showing an association with distance from the facilities. Post closure, residents had difficulty in identifying the type of smell due to the decrease in odour level. During both surveys, older residents reported most concern about the potentially adverse health impacts of long-term exposure to odours from MSW facilities. However, although awareness of MSW facilities and concern about potentially adverse health impacts varied according to the characteristics of residents in 2003, substantial media coverage produced an equalisation effect and increased knowledge about the type of facilities and how they operated. It is possible that residents of the village nearest to the facilities reported lower awareness of and concern about odour and environmental pollution because the municipality received economic compensation for their presence. PMID:23321503

  7. Consumption of garlic positively affects hedonic perception of axillary body odour.

    PubMed

    Fialová, Jitka; Roberts, S Craig; Havlíček, Jan

    2016-02-01

    Beneficial health properties of garlic, as well as its most common adverse effect - distinctive breath odour - are well-known. In contrast, analogous research on the effect of garlic on axillary odour is currently missing. Here, in three studies varying in the amount and nature of garlic provided (raw garlic in study 1 and 2, garlic capsules in study 3), we tested the effect of garlic consumption on the quality of axillary odour. A balanced within-subject experimental design was used. In total, 42 male odour donors were allocated to either a "garlic" or "non-garlic" condition, after which they wore axillary pads for 12 h to collect body odour. One week later, the conditions were reversed. Odour samples were then judged for their pleasantness, attractiveness, masculinity and intensity by 82 women. We found no significant differences in ratings of any characteristics in study 1. However, the odour of donors after an increased garlic dosage was assessed as significantly more pleasant, attractive and less intense (study 2), and more attractive and less intense in study 3. Our results indicate that garlic consumption may have positive effects on perceived body odour hedonicity, perhaps due to its health effects (e.g., antioxidant properties, antimicrobial activity). PMID:26551789

  8. Consumption of garlic positively affects hedonic perception of axillary body odour.

    PubMed

    Fialová, Jitka; Roberts, S Craig; Havlíček, Jan

    2016-02-01

    Beneficial health properties of garlic, as well as its most common adverse effect - distinctive breath odour - are well-known. In contrast, analogous research on the effect of garlic on axillary odour is currently missing. Here, in three studies varying in the amount and nature of garlic provided (raw garlic in study 1 and 2, garlic capsules in study 3), we tested the effect of garlic consumption on the quality of axillary odour. A balanced within-subject experimental design was used. In total, 42 male odour donors were allocated to either a "garlic" or "non-garlic" condition, after which they wore axillary pads for 12 h to collect body odour. One week later, the conditions were reversed. Odour samples were then judged for their pleasantness, attractiveness, masculinity and intensity by 82 women. We found no significant differences in ratings of any characteristics in study 1. However, the odour of donors after an increased garlic dosage was assessed as significantly more pleasant, attractive and less intense (study 2), and more attractive and less intense in study 3. Our results indicate that garlic consumption may have positive effects on perceived body odour hedonicity, perhaps due to its health effects (e.g., antioxidant properties, antimicrobial activity).

  9. Understanding the Odour Spaces: A Step towards Solving Olfactory Stimulus-Percept Problem

    PubMed Central

    Kumar, Ritesh; Bhondekar, Amol P.

    2015-01-01

    Odours are highly complex, relying on hundreds of receptors, and people are known to disagree in their linguistic descriptions of smells. It is partly due to these facts that, it is very hard to map the domain of odour molecules or their structure to that of perceptual representations, a problem that has been referred to as the Structure-Odour-Relationship. We collected a number of diverse open domain databases of odour molecules having unorganised perceptual descriptors, and developed a graphical method to find the similarity between perceptual descriptors; which is intuitive and can be used to identify perceptual classes. We then separately projected the physico-chemical and perceptual features of these molecules in a non-linear dimension and clustered the similar molecules. We found a significant overlap between the spatial positioning of the clustered molecules in the physico-chemical and perceptual spaces. We also developed a statistical method of predicting the perceptual qualities of a novel molecule using its physico-chemical properties with high receiver operating characteristics(ROC). PMID:26484763

  10. Understanding the Odour Spaces: A Step towards Solving Olfactory Stimulus-Percept Problem.

    PubMed

    Kumar, Ritesh; Kaur, Rishemjit; Auffarth, Benjamin; Bhondekar, Amol P

    2015-01-01

    Odours are highly complex, relying on hundreds of receptors, and people are known to disagree in their linguistic descriptions of smells. It is partly due to these facts that, it is very hard to map the domain of odour molecules or their structure to that of perceptual representations, a problem that has been referred to as the Structure-Odour-Relationship. We collected a number of diverse open domain databases of odour molecules having unorganised perceptual descriptors, and developed a graphical method to find the similarity between perceptual descriptors; which is intuitive and can be used to identify perceptual classes. We then separately projected the physico-chemical and perceptual features of these molecules in a non-linear dimension and clustered the similar molecules. We found a significant overlap between the spatial positioning of the clustered molecules in the physico-chemical and perceptual spaces. We also developed a statistical method of predicting the perceptual qualities of a novel molecule using its physico-chemical properties with high receiver operating characteristics(ROC). PMID:26484763

  11. Speed and accuracy in nest-mate recognition: a hover wasp prioritizes face recognition over colony odour cues to minimize intrusion by outsiders.

    PubMed

    Baracchi, D; Petrocelli, I; Chittka, L; Ricciardi, G; Turillazzi, S

    2015-03-01

    Social insects have evolved sophisticated recognition systems enabling them to accept nest-mates but reject alien conspecifics. In the social wasp, Liostenogaster flavolineata (Stenogastrinae), individuals differ in their cuticular hydrocarbon profiles according to colony membership; each female also possesses a unique (visual) facial pattern. This species represents a unique model to understand how vision and olfaction are integrated and the extent to which wasps prioritize one channel over the other to discriminate aliens and nest-mates. Liostenogaster flavolineata females are able to discriminate between alien and nest-mate females using facial patterns or chemical cues in isolation. However, the two sensory modalities are not equally efficient in the discrimination of 'friend' from 'foe'. Visual cues induce an increased number of erroneous attacks on nest-mates (false alarms), but such attacks are quickly aborted and never result in serious injury. Odour cues, presented in isolation, result in an increased number of misses: erroneous acceptances of outsiders. Interestingly, wasps take the relative efficiencies of the two sensory modalities into account when making rapid decisions about colony membership of an individual: chemical profiles are entirely ignored when the visual and chemical stimuli are presented together. Thus, wasps adopt a strategy to 'err on the safe side' by memorizing individual faces to recognize colony members, and disregarding odour cues to minimize the risk of intrusion from colony outsiders.

  12. Speed and accuracy in nest-mate recognition: a hover wasp prioritizes face recognition over colony odour cues to minimize intrusion by outsiders

    PubMed Central

    Baracchi, D.; Petrocelli, I.; Chittka, L.; Ricciardi, G.; Turillazzi, S.

    2015-01-01

    Social insects have evolved sophisticated recognition systems enabling them to accept nest-mates but reject alien conspecifics. In the social wasp, Liostenogaster flavolineata (Stenogastrinae), individuals differ in their cuticular hydrocarbon profiles according to colony membership; each female also possesses a unique (visual) facial pattern. This species represents a unique model to understand how vision and olfaction are integrated and the extent to which wasps prioritize one channel over the other to discriminate aliens and nest-mates. Liostenogaster flavolineata females are able to discriminate between alien and nest-mate females using facial patterns or chemical cues in isolation. However, the two sensory modalities are not equally efficient in the discrimination of ‘friend’ from ‘foe’. Visual cues induce an increased number of erroneous attacks on nest-mates (false alarms), but such attacks are quickly aborted and never result in serious injury. Odour cues, presented in isolation, result in an increased number of misses: erroneous acceptances of outsiders. Interestingly, wasps take the relative efficiencies of the two sensory modalities into account when making rapid decisions about colony membership of an individual: chemical profiles are entirely ignored when the visual and chemical stimuli are presented together. Thus, wasps adopt a strategy to ‘err on the safe side’ by memorizing individual faces to recognize colony members, and disregarding odour cues to minimize the risk of intrusion from colony outsiders. PMID:25652836

  13. Speed and accuracy in nest-mate recognition: a hover wasp prioritizes face recognition over colony odour cues to minimize intrusion by outsiders.

    PubMed

    Baracchi, D; Petrocelli, I; Chittka, L; Ricciardi, G; Turillazzi, S

    2015-03-01

    Social insects have evolved sophisticated recognition systems enabling them to accept nest-mates but reject alien conspecifics. In the social wasp, Liostenogaster flavolineata (Stenogastrinae), individuals differ in their cuticular hydrocarbon profiles according to colony membership; each female also possesses a unique (visual) facial pattern. This species represents a unique model to understand how vision and olfaction are integrated and the extent to which wasps prioritize one channel over the other to discriminate aliens and nest-mates. Liostenogaster flavolineata females are able to discriminate between alien and nest-mate females using facial patterns or chemical cues in isolation. However, the two sensory modalities are not equally efficient in the discrimination of 'friend' from 'foe'. Visual cues induce an increased number of erroneous attacks on nest-mates (false alarms), but such attacks are quickly aborted and never result in serious injury. Odour cues, presented in isolation, result in an increased number of misses: erroneous acceptances of outsiders. Interestingly, wasps take the relative efficiencies of the two sensory modalities into account when making rapid decisions about colony membership of an individual: chemical profiles are entirely ignored when the visual and chemical stimuli are presented together. Thus, wasps adopt a strategy to 'err on the safe side' by memorizing individual faces to recognize colony members, and disregarding odour cues to minimize the risk of intrusion from colony outsiders. PMID:25652836

  14. Effects of in utero odorant exposure on neuroanatomical development of the olfactory bulb and odour preferences

    PubMed Central

    Todrank, Josephine; Heth, Giora; Restrepo, Diego

    2011-01-01

    Human babies and other young mammals prefer food odours and flavours of their mother's diet during pregnancy as well as their mother's individually distinctive odour. Newborn mice also prefer the individual odours of more closely related—even unfamiliar—lactating females. If exposure to in utero odorants—which include metabolites from the mother's diet and the foetus's genetically determined individual odour—helps shape the neuroanatomical development of the olfactory bulb, this could influence the perception of such biologically important odours that are preferred after birth. We exposed gene-targeted mice during gestation and nursing to odorants that activate GFP-tagged olfactory receptors (ORs) and then measured the effects on the size of tagged glomeruli in the olfactory bulb where axons from olfactory sensory neurons (OSNs) coalesce by OR type. We found significantly larger tagged glomeruli in mice exposed to these activating odorants in amniotic fluid, and later in mother's milk, as well as significant preferences for the activating odour. Larger glomeruli comprising OSNs that respond to consistently encountered odorants should enhance detection and discrimination of these subsequently preferred odours, which in nature would facilitate selection of palatable foods and kin recognition, through similarities in individual odours of relatives. PMID:21123261

  15. Modelling to solve odour problems.

    PubMed

    Childs, P S; Dunn, A J

    2001-01-01

    The use of dispersion modelling is a powerful tool to establish levels of treatment required to remove odour complaints. Odour is an extremely sensitive issue and is key to the public perception of wastewater environmental protection. This paper describes a case study of the successful resolution of long-standing odour problems at the East Worthing Wastewater Treatment Works (WTW), on the South Coast of England, utilising modelling and appropriate treatment technologies. A number of odour surveys have been conducted on the site to identify the major sources on the works, which were found to be the sludge press house and the primary settlement tanks, situated only 10 metres from the nearest properties. As a result attempts to resolve the odour problem have been made including the covering of identified sources, treating extract using activated carbon filters and installing perfume sprays. During the site development all sources were contained and ventilated to a 60,000 m3/hr Jones & Attwood ODORGARD unit. Its requirement was to ensure that no receptor was exposed to a concentration in excess of 4 ouEm3 (Odour units), in accordance with the odour planning condition. Dispersal modelling was performed to determine the maximum permissible outlet concentration. The results of the modelling exercise established that emissions from the odour control plant should not exceed 675 ouEm3 to ensure that the receptor standard was attained. An optimisation programme was conducted to ensure that the unit was providing the optimum level of treatment prior to taking the olfactometry samples. Following the plant's optimisation the results of the olfactometry analysis confirmed that the discharge levels were below the required 670 ouEm3. Since completion of the sludge treatment centre scheme there have been no registered odour complaints directed at the East Worthing WTW, and the local air quality has been greatly improved for the residents surrounding the works.

  16. Behavioral model of visual perception and recognition

    NASA Astrophysics Data System (ADS)

    Rybak, Ilya A.; Golovan, Alexander V.; Gusakova, Valentina I.

    1993-09-01

    In the processes of visual perception and recognition human eyes actively select essential information by way of successive fixations at the most informative points of the image. A behavioral program defining a scanpath of the image is formed at the stage of learning (object memorizing) and consists of sequential motor actions, which are shifts of attention from one to another point of fixation, and sensory signals expected to arrive in response to each shift of attention. In the modern view of the problem, invariant object recognition is provided by the following: (1) separated processing of `what' (object features) and `where' (spatial features) information at high levels of the visual system; (2) mechanisms of visual attention using `where' information; (3) representation of `what' information in an object-based frame of reference (OFR). However, most recent models of vision based on OFR have demonstrated the ability of invariant recognition of only simple objects like letters or binary objects without background, i.e. objects to which a frame of reference is easily attached. In contrast, we use not OFR, but a feature-based frame of reference (FFR), connected with the basic feature (edge) at the fixation point. This has provided for our model, the ability for invariant representation of complex objects in gray-level images, but demands realization of behavioral aspects of vision described above. The developed model contains a neural network subsystem of low-level vision which extracts a set of primary features (edges) in each fixation, and high- level subsystem consisting of `what' (Sensory Memory) and `where' (Motor Memory) modules. The resolution of primary features extraction decreases with distances from the point of fixation. FFR provides both the invariant representation of object features in Sensor Memory and shifts of attention in Motor Memory. Object recognition consists in successive recall (from Motor Memory) and execution of shifts of attention and

  17. Odour suppression in binary mixtures.

    PubMed

    Cashion, Larry; Livermore, Andrew; Hummel, Thomas

    2006-10-01

    It has been suggested that odours causing stronger trigeminal activation suppress weaker trigeminal stimuli and that mixed olfactory-trigeminal stimuli suppress odorants that only activate one of these systems. Volunteer normosmic participants (n=20) were exposed to six odorants with varying trigeminal impact to test the hypothesis that more intense "trigeminal" odorants would suppress weaker trigeminal stimuli in binary odour mixtures. It was also hypothesised that stronger trigeminal odorants would dominate six-odour mixtures. The predicted linear pattern of suppression was not seen, with a quadratic model emerging from the data. Stronger trigeminal stimuli failed to dominate six-odour mixtures. Despite the fact that the major hypothesis was not supported, it can be hypothesised from this experiment that the effect of suppression in binary mixtures is reliant upon two major effects: (1) the association formed between odours and the multiple memory systems that they interact with during the encoding and recognition processes, and (2) the balance between activation of the olfactory and trigeminal systems.

  18. Impaired odour discrimination on desynchronization of odour-encoding neural assemblies

    NASA Astrophysics Data System (ADS)

    Stopfer, Mark; Bhagavan, Seetha; Smith, Brian H.; Laurent, Gilles

    1997-11-01

    Stimulus-evoked oscillatory synchronization of neural assemblies has been described in the olfactory and visual systems of several vertebrates and invertebrates. In locusts, information about odour identity is contained in the timing of action potentials in an oscillatory population response, suggesting that oscillations may reflect a common reference for messages encoded in time. Although the stimulus-evoked oscillatory phenomenon is reliable, its roles in sensation, perception, memory formation and pattern recognition remain to be demonstrated - a task requiring a behavioural paradigm. Using honeybees, we now demonstrate that odour encoding involves, as it does in locusts, the oscillatory synchronization of assemblies of projection neurons and that this synchronization is also selectively abolished by picrotoxin, an antagonist of the GABAA (γ-aminobutyric acid) receptor. By using a behavioural learning paradigm, we show that picrotoxin-induced desynchronization impairs the discrimination of molecularly similar odorants, but not that of dissimilar odorants. It appears, therefore, that oscillatory synchronization of neuronal assemblies is functionally relevant, and essential for fine sensory discrimination. This suggests that oscillatory synchronization and the kind of temporal encoding it affords provide an additional dimension by which the brain could segment spatially overlapping stimulus representations.

  19. Perception and recognition of faces in adolescence

    PubMed Central

    Fuhrmann, D.; Knoll, L. J.; Sakhardande, A. L.; Speekenbrink, M.; Kadosh, K. C.; Blakemore, S. -J.

    2016-01-01

    Most studies on the development of face cognition abilities have focussed on childhood, with early maturation accounts contending that face cognition abilities are mature by 3–5 years. Late maturation accounts, in contrast, propose that some aspects of face cognition are not mature until at least 10 years. Here, we measured face memory and face perception, two core face cognition abilities, in 661 participants (397 females) in four age groups (younger adolescents (11.27–13.38 years); mid-adolescents (13.39–15.89 years); older adolescents (15.90–18.00 years); and adults (18.01–33.15 years)) while controlling for differences in general cognitive ability. We showed that both face cognition abilities mature relatively late, at around 16 years, with a female advantage in face memory, but not in face perception, both in adolescence and adulthood. Late maturation in the face perception task was driven mainly by protracted development in identity perception, while gaze perception abilities were already comparatively mature in early adolescence. These improvements in the ability to memorize, recognize and perceive faces during adolescence may be related to increasing exploratory behaviour and exposure to novel faces during this period of life. PMID:27647477

  20. Perception and recognition of faces in adolescence.

    PubMed

    Fuhrmann, D; Knoll, L J; Sakhardande, A L; Speekenbrink, M; Kadosh, K C; Blakemore, S-J

    2016-01-01

    Most studies on the development of face cognition abilities have focussed on childhood, with early maturation accounts contending that face cognition abilities are mature by 3-5 years. Late maturation accounts, in contrast, propose that some aspects of face cognition are not mature until at least 10 years. Here, we measured face memory and face perception, two core face cognition abilities, in 661 participants (397 females) in four age groups (younger adolescents (11.27-13.38 years); mid-adolescents (13.39-15.89 years); older adolescents (15.90-18.00 years); and adults (18.01-33.15 years)) while controlling for differences in general cognitive ability. We showed that both face cognition abilities mature relatively late, at around 16 years, with a female advantage in face memory, but not in face perception, both in adolescence and adulthood. Late maturation in the face perception task was driven mainly by protracted development in identity perception, while gaze perception abilities were already comparatively mature in early adolescence. These improvements in the ability to memorize, recognize and perceive faces during adolescence may be related to increasing exploratory behaviour and exposure to novel faces during this period of life. PMID:27647477

  1. Odour Detection Methods: Olfactometry and Chemical Sensors

    PubMed Central

    Brattoli, Magda; de Gennaro, Gianluigi; de Pinto, Valentina; Loiotile, Annamaria Demarinis; Lovascio, Sara; Penza, Michele

    2011-01-01

    The complexity of the odours issue arises from the sensory nature of smell. From the evolutionary point of view olfaction is one of the oldest senses, allowing for seeking food, recognizing danger or communication: human olfaction is a protective sense as it allows the detection of potential illnesses or infections by taking into account the odour pleasantness/unpleasantness. Odours are mixtures of light and small molecules that, coming in contact with various human sensory systems, also at very low concentrations in the inhaled air, are able to stimulate an anatomical response: the experienced perception is the odour. Odour assessment is a key point in some industrial production processes (i.e., food, beverages, etc.) and it is acquiring steady importance in unusual technological fields (i.e., indoor air quality); this issue mainly concerns the environmental impact of various industrial activities (i.e., tanneries, refineries, slaughterhouses, distilleries, civil and industrial wastewater treatment plants, landfills and composting plants) as sources of olfactory nuisances, the top air pollution complaint. Although the human olfactory system is still regarded as the most important and effective “analytical instrument” for odour evaluation, the demand for more objective analytical methods, along with the discovery of materials with chemo-electronic properties, has boosted the development of sensor-based machine olfaction potentially imitating the biological system. This review examines the state of the art of both human and instrumental sensing currently used for the detection of odours. The olfactometric techniques employing a panel of trained experts are discussed and the strong and weak points of odour assessment through human detection are highlighted. The main features and the working principles of modern electronic noses (E-Noses) are then described, focusing on their better performances for environmental analysis. Odour emission monitoring carried out

  2. Conversion of the chemical concentration of odorous mixtures into odour concentration and odour intensity: A comparison of methods

    NASA Astrophysics Data System (ADS)

    Wu, Chuandong; Liu, Jiemin; Zhao, Peng; Piringer, Martin; Schauberger, Günther

    2016-02-01

    Continuous odour measurements both of emissions as well as ambient concentrations are seldom realised, mainly because of their high costs. They are therefore often substituted by concentration measurements of odorous substances. Then a conversion of the chemical concentrations C (mg m-3) into odour concentrations COD (ouE m-3) and odour intensities OI is necessary. Four methods to convert the concentrations of single substances to the odour concentrations and odour intensities of an odorous mixture are investigated: (1) direct use of measured concentrations, (2) the sum of the odour activity value SOAV, (3) the sum of the odour intensities SOI, and (4) the equivalent odour concentration EOC, as a new method. The methods are evaluated with olfactometric measurements of seven substances as well as their mixtures. The results indicate that the SOI and EOC conversion methods deliver reliable values. These methods use not only the odour threshold concentration but also the slope of the Weber-Fechner law to include the sensitivity of the odour perception of the individual substances. They fulfil the criteria of an objective conversion without the need of a further calibration by additional olfactometric measurements.

  3. Diesel exhaust rapidly degrades floral odours used by honeybees.

    PubMed

    Girling, Robbie D; Lusebrink, Inka; Farthing, Emily; Newman, Tracey A; Poppy, Guy M

    2013-10-03

    Honeybees utilise floral odours when foraging for flowers; we investigated whether diesel exhaust pollution could interrupt these floral odour stimuli. A synthetic blend of eight floral chemicals, identified from oilseed rape, was exposed to diesel exhaust pollution. Within one minute of exposure the abundances of four of the chemicals were significantly lowered, with two components rendered undetectable. Honeybees were trained to recognise the full synthetic odour mix; altering the blend, by removing the two chemicals rendered undetectable, significantly reduced the ability of the trained honeybees to recognize the altered odour. Furthermore, we found that at environmentally relevant levels the mono-nitrogen oxide (NOx) fraction of the exhaust gases was a key facilitator of this odour degradation. Such changes in recognition may impact upon a honeybee's foraging efficiency and therefore the pollination services that they provide.

  4. The scent of mixtures: rules of odour processing in ants.

    PubMed

    Perez, Margot; Giurfa, Martin; d'Ettorre, Patrizia

    2015-03-02

    Natural odours are complex blends of numerous components. Understanding how animals perceive odour mixtures is central to multiple disciplines. Here we focused on carpenter ants, which rely on odours in various behavioural contexts. We studied overshadowing, a phenomenon that occurs when animals having learnt a binary mixture respond less to one component than to the other, and less than when this component was learnt alone. Ants were trained individually with alcohols and aldehydes varying in carbon-chain length, either as single odours or binary mixtures. They were then tested with the mixture and the components. Overshadowing resulted from the interaction between chain length and functional group: alcohols overshadowed aldehydes, and longer chain lengths overshadowed shorter ones; yet, combinations of these factors could cancel each other and suppress overshadowing. Our results show how ants treat binary olfactory mixtures and set the basis for predictive analyses of odour perception in insects.

  5. The scent of mixtures: rules of odour processing in ants

    PubMed Central

    Perez, Margot; Giurfa, Martin; d'Ettorre, Patrizia

    2015-01-01

    Natural odours are complex blends of numerous components. Understanding how animals perceive odour mixtures is central to multiple disciplines. Here we focused on carpenter ants, which rely on odours in various behavioural contexts. We studied overshadowing, a phenomenon that occurs when animals having learnt a binary mixture respond less to one component than to the other, and less than when this component was learnt alone. Ants were trained individually with alcohols and aldehydes varying in carbon-chain length, either as single odours or binary mixtures. They were then tested with the mixture and the components. Overshadowing resulted from the interaction between chain length and functional group: alcohols overshadowed aldehydes, and longer chain lengths overshadowed shorter ones; yet, combinations of these factors could cancel each other and suppress overshadowing. Our results show how ants treat binary olfactory mixtures and set the basis for predictive analyses of odour perception in insects. PMID:25726692

  6. The scent of mixtures: rules of odour processing in ants.

    PubMed

    Perez, Margot; Giurfa, Martin; d'Ettorre, Patrizia

    2015-01-01

    Natural odours are complex blends of numerous components. Understanding how animals perceive odour mixtures is central to multiple disciplines. Here we focused on carpenter ants, which rely on odours in various behavioural contexts. We studied overshadowing, a phenomenon that occurs when animals having learnt a binary mixture respond less to one component than to the other, and less than when this component was learnt alone. Ants were trained individually with alcohols and aldehydes varying in carbon-chain length, either as single odours or binary mixtures. They were then tested with the mixture and the components. Overshadowing resulted from the interaction between chain length and functional group: alcohols overshadowed aldehydes, and longer chain lengths overshadowed shorter ones; yet, combinations of these factors could cancel each other and suppress overshadowing. Our results show how ants treat binary olfactory mixtures and set the basis for predictive analyses of odour perception in insects. PMID:25726692

  7. Gibberellin Perception by the Gibberellin Receptor and its Effector Recognition

    NASA Astrophysics Data System (ADS)

    Hakoshima, Toshio; Murase, Kohji; Hirano, Yoshinori; Sun, Tai-Ping

    Gibberellins control a diverse range of growth and developmental processes in higher plants and have been widely utilized in the agricultural industry. By binding to a nuclear receptor GIBBERELLIN INSENSITIVE DWARF1 (GID1), gibberellins regulate gene expression by promoting degradation of the transcriptional regulator DELLA proteins. The precise manner in which GID1 discriminates and becomes activated by bioactive gibberellins for specific binding to DELLA proteins remains unclear. We present the crystal structure of a ternary complex of Arabidopsis thaliana GID1A, a bioactive gibberellin and the N-terminal DELLA domain of GAI. In this complex, GID1a occludes gibberellin in a deep binding pocket covered by its N-terminal helical switch region, which in turn interacts with the DELLA domain containing DELLA, VHYNP and LExLE motifs. Our results establish a structural model of a plant hormone receptor which is distinct from the hormone-perception mechanism and effector recognition of the known auxin receptors.

  8. Sign language perception research for improving automatic sign language recognition

    NASA Astrophysics Data System (ADS)

    ten Holt, Gineke A.; Arendsen, Jeroen; de Ridder, Huib; Koenderink-van Doorn, Andrea J.; Reinders, Marcel J. T.; Hendriks, Emile A.

    2009-02-01

    Current automatic sign language recognition (ASLR) seldom uses perceptual knowledge about the recognition of sign language. Using such knowledge can improve ASLR because it can give an indication which elements or phases of a sign are important for its meaning. Also, the current generation of data-driven ASLR methods has shortcomings which may not be solvable without the use of knowledge on human sign language processing. Handling variation in the precise execution of signs is an example of such shortcomings: data-driven methods (which include almost all current methods) have difficulty recognizing signs that deviate too much from the examples that were used to train the method. Insight into human sign processing is needed to solve these problems. Perceptual research on sign language can provide such insights. This paper discusses knowledge derived from a set of sign perception experiments, and the application of such knowledge in ASLR. Among the findings are the facts that not all phases and elements of a sign are equally informative, that defining the 'correct' form for a sign is not trivial, and that statistical ASLR methods do not necessarily arrive at sign representations that resemble those of human beings. Apparently, current ASLR methods are quite different from human observers: their method of learning gives them different sign definitions, they regard each moment and element of a sign as equally important and they employ a single definition of 'correct' for all circumstances. If the object is for an ASLR method to handle natural sign language, then the insights from sign perception research must be integrated into ASLR.

  9. On the Relationship between Memory and Perception: Sequential Dependencies in Recognition Memory Testing

    ERIC Educational Resources Information Center

    Malmberg, Kenneth J.; Annis, Jeffrey

    2012-01-01

    Many models of recognition are derived from models originally applied to perception tasks, which assume that decisions from trial to trial are independent. While the independence assumption is violated for many perception tasks, we present the results of several experiments intended to relate memory and perception by exploring sequential…

  10. Dialogue procedures for the management of odour related community conflicts.

    PubMed

    Sucker, K

    2009-01-01

    In the German Guideline on Odour in Ambient Air (GOAA) statements about the degree of residential odour annoyance are based on the frequency of recognisable odours and hedonic tone. The use of olfactory standards to adequately estimate the annoyance impact is limited if, for example, worry about adverse health outcomes significantly influences the annoyance response of the population. This report introduces dialogue procedures as complementary measures to consider the complainants' subjective perceptions and worries adequately. At first, it is illustrated that odour exposure and number of odour complaints are not necessarily correlated. Then the "interest analysis" and the five steps of a dialogue procedure are presented. A dialogue procedure can be initiated in "quiet times" - where the focus is on trust building and on the development of adequate communication strategies to promote realistic risk reception - as well as in order to establish a successful conflict resolution process if the issue is complex and emotionally discussed. After that, two examples of handling odour complaints are shown. Finally, considerations applying dialogue procedures as a tool to advance odour annoyance mitigation are outlined. PMID:19273885

  11. Recognition of staff nurse job performance and achievements: staff and manager perceptions.

    PubMed

    Cronin, S N; Becherer, D

    1999-01-01

    Recognition for job performance is central to staff nurse morale. However, little research has been done to identify recognition methods most valued by nurses themselves. The authors report results of a multisite survey conducted to compare staff and manager perceptions of meaningful recognition behaviors. They provide data for developing management interventions that may help to improve morale and increase retention. Given the financial constraints of the current environment, the nonmonetary recognition practices identified are of particular significance.

  12. Bayesian Action-Perception loop modeling: Application to trajectory generation and recognition using internal motor simulation

    NASA Astrophysics Data System (ADS)

    Gilet, Estelle; Diard, Julien; Palluel-Germain, Richard; Bessière, Pierre

    2011-03-01

    This paper is about modeling perception-action loops and, more precisely, the study of the influence of motor knowledge during perception tasks. We use the Bayesian Action-Perception (BAP) model, which deals with the sensorimotor loop involved in reading and writing cursive isolated letters and includes an internal simulation of movement loop. By using this probabilistic model we simulate letter recognition, both with and without internal motor simulation. Comparison of their performance yields an experimental prediction, which we set forth.

  13. Odour-based kin discrimination in the cooperatively breeding meerkat.

    PubMed

    Leclaire, Sarah; Nielsen, Johanna F; Thavarajah, Nathan K; Manser, Marta; Clutton-Brock, Tim H

    2013-02-23

    Kin recognition is a useful ability for animals, facilitating cooperation among relatives and avoidance of excessive kin competition or inbreeding. In meerkats, Suricata suricatta, encounters between unfamiliar kin are relatively frequent, and kin recognition by phenotype matching is expected to avoid inbreeding with close relatives. Here, we investigate whether female meerkats are able to discriminate the scent of unfamiliar kin from unfamiliar non-kin. Dominant females were presented with anal gland secretion from unfamiliar individuals that varied in their relatedness. Our result indicates that females spent more time investigating the scent of related than unrelated unfamiliar individuals, suggesting that females may use a phenotype matching mechanism (or recognition alleles) to discriminate the odour of their kin from the odour of their non-kin. Our study provides a key starting point for further investigations into the use of kin recognition for inbreeding avoidance in the widely studied meerkat.

  14. Odour-based kin discrimination in the cooperatively breeding meerkat.

    PubMed

    Leclaire, Sarah; Nielsen, Johanna F; Thavarajah, Nathan K; Manser, Marta; Clutton-Brock, Tim H

    2013-02-23

    Kin recognition is a useful ability for animals, facilitating cooperation among relatives and avoidance of excessive kin competition or inbreeding. In meerkats, Suricata suricatta, encounters between unfamiliar kin are relatively frequent, and kin recognition by phenotype matching is expected to avoid inbreeding with close relatives. Here, we investigate whether female meerkats are able to discriminate the scent of unfamiliar kin from unfamiliar non-kin. Dominant females were presented with anal gland secretion from unfamiliar individuals that varied in their relatedness. Our result indicates that females spent more time investigating the scent of related than unrelated unfamiliar individuals, suggesting that females may use a phenotype matching mechanism (or recognition alleles) to discriminate the odour of their kin from the odour of their non-kin. Our study provides a key starting point for further investigations into the use of kin recognition for inbreeding avoidance in the widely studied meerkat. PMID:23234867

  15. Lexical support for phonetic perception during nonnative spoken word recognition.

    PubMed

    Samuel, Arthur G; Frost, Ram

    2015-12-01

    Second language comprehension is generally not as efficient and effective as native language comprehension. In the present study, we tested the hypothesis that lower-level processes such as lexical support for phonetic perception are a contributing factor to these differences. For native listeners, it has been shown that the perception of ambiguous acoustic–phonetic segments is driven by lexical factors (Samuel Psychological Science, 12, 348-351, 2001). Here, we tested whether nonnative listeners can use lexical context in the same way. Native Hebrew speakers living in Israel were tested with American English stimuli. When subtle acoustic cues in the stimuli worked against the lexical context, these nonnative speakers showed no evidence of lexical guidance of phonetic perception. This result conflicts with the performance of native speakers, who demonstrate lexical effects on phonetic perception even with conflicting acoustic cues. When stimuli without any conflicting cues were used, the native Hebrew subjects produced results similar to those of native English speakers, showing lexical support for phonetic perception in their second language. In contrast, native Arabic speakers, who were less proficient in English than the native Hebrew speakers, showed no ability to use lexical activation to support phonetic perception, even without any conflicting cues. These results reinforce previous demonstrations of lexical support of phonetic perception and demonstrate how proficiency modulates the use of lexical information in driving phonetic perception. PMID:26866066

  16. [Acoustic recognition of emotions and musical perceptive abilities in young deaf person].

    PubMed

    Fiol, L; Rousteau, G

    2012-01-01

    What influence does being deaf have on the ability to recognise emotions in other people? What perceptive abilities can be found in deaf people that are based on the acoustic recognition of emotions? Studies concerning the most useful acoustic clues in the recognition of emotions remain scarce. Beyond the uttered words, emotions are perceptible through the music of speech i.e. its words, its parameters (namely the intensity), the pitch and the timbre or colour of a sound, as well as its rhythm. The protocol of assessment developed in this study shows evidence of a correlation between the recognition of fundamental emotions and the perceptive musical abilities of deaf patients. This concept is relevant when regarding any deaf patient; irrespective of hearing aid type or re-education method. PMID:23074825

  17. Transcranial doppler assessment of cerebral flow velocity during perception and recognition of melodies.

    PubMed

    Matteis, M; Silvestrini, M; Troisi, E; Cupini, L M; Caltagirone, C

    1997-07-01

    The role of each cerebral hemisphere in the perception and recognition of musical information is not yet well understood. We studied cerebral blood flow changes during a melody perception task and a melody recognition task. Blood flow velocity in the two middle cerebral arteries of twenty right-handed musically naif volunteers were simultaneously measured by means of bilateral transcranial Doppler ultrasonography during two minutes of passive melody listening and two minutes of a melody recognition task. With respect to baseline values, a bilateral increase of flow velocity occurred in the middle cerebral arteries with a non-significant trend for the right artery during the melody perception task. During the melody recognition task, a significant increase in flow velocity was recorded on the right side with respect to the left side, where a slight simultaneous decrease was found. Our data suggest that melody perception requires bilateral activation of hemispheres and melody recognition mainly an activation of the right hemisphere. This study confirms the ability of transcranial Doppler ultrasonography to correlate artery flow dynamics with selective cerebral activation. PMID:9168166

  18. Odour emission inventory of German wastewater treatment plants--odour flow rates and odour emission capacity.

    PubMed

    Frechen, F-B

    2004-01-01

    Wastewater Treatment plants can cause odour emissions that may lead to significant odour annoyance in their vicinity. Thus, over the past 20 years, several measurements were taken of the odour emissions that occur at WWTPs of different sizes, treatment technology, plant design and under different operating conditions. The specific aspects of odour sampling and measurement have to be considered. I presented some of the results of my odour emission measurements 11 years ago. However, it is now necessary to update the figures by evaluating newer measurement results obtained from measurements taken from 1994 to 2003. These are presented in this paper. Also, the paper highlights the odour emission capacity (OEC) measurement technique which characterises liquids and can be used to assess the results achieved by different types of treatment in the liquid phase, e.g. in a sewerage system. In addition, the OEC is a suitable parameter to set standards for the odorant content of industrial wastewaters that are discharged into the publicly owned sewerage system.

  19. Binary ROCs in Perception and Recognition Memory Are Curved

    ERIC Educational Resources Information Center

    Dube, Chad; Rotello, Caren M.

    2012-01-01

    In recognition memory, a classic finding is that receiver operating characteristics (ROCs) are curvilinear. This has been taken to support the fundamental assumptions of signal detection theory (SDT) over discrete-state models such as the double high-threshold model (2HTM), which predicts linear ROCs. Recently, however, Broder and Schutz (2009)…

  20. A Rhythm Recognition Computer Program to Advocate Interactivist Perception

    ERIC Educational Resources Information Center

    Buisson, Jean-Christophe

    2004-01-01

    This paper advocates the main ideas of the interactive model of representation of Mark Bickhard and the assimilation/accommodation framework of Jean Piaget, through a rhythm recognition demonstration program. Although completely unsupervised, the program progressively learns to recognize more and more complex rhythms struck on the user's keyboard.…

  1. Bayesian Action–Perception Computational Model: Interaction of Production and Recognition of Cursive Letters

    PubMed Central

    Gilet, Estelle; Diard, Julien; Bessière, Pierre

    2011-01-01

    In this paper, we study the collaboration of perception and action representations involved in cursive letter recognition and production. We propose a mathematical formulation for the whole perception–action loop, based on probabilistic modeling and Bayesian inference, which we call the Bayesian Action–Perception (BAP) model. Being a model of both perception and action processes, the purpose of this model is to study the interaction of these processes. More precisely, the model includes a feedback loop from motor production, which implements an internal simulation of movement. Motor knowledge can therefore be involved during perception tasks. In this paper, we formally define the BAP model and show how it solves the following six varied cognitive tasks using Bayesian inference: i) letter recognition (purely sensory), ii) writer recognition, iii) letter production (with different effectors), iv) copying of trajectories, v) copying of letters, and vi) letter recognition (with internal simulation of movements). We present computer simulations of each of these cognitive tasks, and discuss experimental predictions and theoretical developments. PMID:21674043

  2. Auditory perception vs. recognition: representation of complex communication sounds in the mouse auditory cortical fields.

    PubMed

    Geissler, Diana B; Ehret, Günter

    2004-02-01

    Details of brain areas for acoustical Gestalt perception and the recognition of species-specific vocalizations are not known. Here we show how spectral properties and the recognition of the acoustical Gestalt of wriggling calls of mouse pups based on a temporal property are represented in auditory cortical fields and an association area (dorsal field) of the pups' mothers. We stimulated either with a call model releasing maternal behaviour at a high rate (call recognition) or with two models of low behavioural significance (perception without recognition). Brain activation was quantified using c-Fos immunocytochemistry, counting Fos-positive cells in electrophysiologically mapped auditory cortical fields and the dorsal field. A frequency-specific labelling in two primary auditory fields is related to call perception but not to the discrimination of the biological significance of the call models used. Labelling related to call recognition is present in the second auditory field (AII). A left hemisphere advantage of labelling in the dorsoposterior field seems to reflect an integration of call recognition with maternal responsiveness. The dorsal field is activated only in the left hemisphere. The spatial extent of Fos-positive cells within the auditory cortex and its fields is larger in the left than in the right hemisphere. Our data show that a left hemisphere advantage in processing of a species-specific vocalization up to recognition is present in mice. The differential representation of vocalizations of high vs. low biological significance, as seen only in higher-order and not in primary fields of the auditory cortex, is discussed in the context of perceptual strategies. PMID:15009150

  3. When family looks strange and strangers look normal: a case of impaired face perception and recognition after stroke.

    PubMed

    Heutink, Joost; Brouwer, Wiebo H; Kums, Evelien; Young, Andy; Bouma, Anke

    2012-02-01

    We describe a patient (JS) with impaired recognition and distorted visual perception of faces after an ischemic stroke. Strikingly, JS reports that the faces of family members look distorted, while faces of other people look normal. After neurological and neuropsychological examination, we assessed response accuracy, response times, and skin conductance responses on a face recognition task in which photographs of close family members, celebrities and unfamiliar people were presented. JS' performance was compared to the performance of three healthy control participants. Results indicate that three aspects of face perception appear to be impaired in JS. First, she has impaired recognition of basic emotional expressions. Second, JS has poor recognition of familiar faces in general, but recognition of close family members is disproportionally impaired compared to faces of celebrities. Third, JS perceives faces of family members as distorted. In this paper we consider whether these impairments can be interpreted in terms of previously described disorders of face perception and recent models for face perception.

  4. Sensing the intruder: a quantitative threshold for recognition cues perception in honeybees

    NASA Astrophysics Data System (ADS)

    Cappa, Federico; Bruschini, Claudia; Cipollini, Maria; Pieraccini, Giuseppe; Cervo, Rita

    2014-02-01

    The ability to discriminate among nestmates and non-nestmate is essential to defend social insect colonies from intruders. Over the years, nestmate recognition has been extensively studied in the honeybee Apis mellifera; nevertheless, the quantitative perceptual aspects at the basis of the recognition system represent an unexplored subject in this species. To test the existence of a cuticular hydrocarbons' quantitative perception threshold for nestmate recognition cues, we conducted behavioural assays by presenting different amounts of a foreign forager's chemical profile to honeybees at the entrance of their colonies. We found an increase in the explorative and aggressive responses as the amount of cues increased based on a threshold mechanism, highlighting the importance of the quantitative perceptual features for the recognition processes in A. mellifera.

  5. A new look at emotion perception: Concepts speed and shape facial emotion recognition.

    PubMed

    Nook, Erik C; Lindquist, Kristen A; Zaki, Jamil

    2015-10-01

    Decades ago, the "New Look" movement challenged how scientists thought about vision by suggesting that conceptual processes shape visual perceptions. Currently, affective scientists are likewise debating the role of concepts in emotion perception. Here, we utilized a repetition-priming paradigm in conjunction with signal detection and individual difference analyses to examine how providing emotion labels-which correspond to discrete emotion concepts-affects emotion recognition. In Study 1, pairing emotional faces with emotion labels (e.g., "sad") increased individuals' speed and sensitivity in recognizing emotions. Additionally, individuals with alexithymia-who have difficulty labeling their own emotions-struggled to recognize emotions based on visual cues alone, but not when emotion labels were provided. Study 2 replicated these findings and further demonstrated that emotion concepts can shape perceptions of facial expressions. Together, these results suggest that emotion perception involves conceptual processing. We discuss the implications of these findings for affective, social, and clinical psychology.

  6. A new look at emotion perception: Concepts speed and shape facial emotion recognition.

    PubMed

    Nook, Erik C; Lindquist, Kristen A; Zaki, Jamil

    2015-10-01

    Decades ago, the "New Look" movement challenged how scientists thought about vision by suggesting that conceptual processes shape visual perceptions. Currently, affective scientists are likewise debating the role of concepts in emotion perception. Here, we utilized a repetition-priming paradigm in conjunction with signal detection and individual difference analyses to examine how providing emotion labels-which correspond to discrete emotion concepts-affects emotion recognition. In Study 1, pairing emotional faces with emotion labels (e.g., "sad") increased individuals' speed and sensitivity in recognizing emotions. Additionally, individuals with alexithymia-who have difficulty labeling their own emotions-struggled to recognize emotions based on visual cues alone, but not when emotion labels were provided. Study 2 replicated these findings and further demonstrated that emotion concepts can shape perceptions of facial expressions. Together, these results suggest that emotion perception involves conceptual processing. We discuss the implications of these findings for affective, social, and clinical psychology. PMID:25938612

  7. Object recognition by triaural perception on a mobile robot

    NASA Astrophysics Data System (ADS)

    Peremans, Herbert; Van Campenhout, Jan M.

    1993-05-01

    To overcome some of the problems associated with the use of ultrasonic sensors for navigation purposes, we propose a measurement system composed of three ultrasonic sensors, one transmitting and three receiving, placed on a moving vehicle. By triangulation this tri-aural sensor is able to determine the position, both distance and bearing, of the objects in the field of view. In this paper, we derive a statistical test which combines consecutive sightings by the moving sensor, of the same object to determine whether it is an edge, a plane or a corner. This test is formulated as a sequential test which guarantees that the object will be recognized after the minimal number of measurements given predetermined error probabilities. We include experimental data showing the object recognition capabilities of the system.

  8. Plant odour plumes as mediators of plant-insect interactions.

    PubMed

    Beyaert, Ivo; Hilker, Monika

    2014-02-01

    Insect olfactory orientation along odour plumes has been studied intensively with respect to pheromonal communication, whereas little knowledge is available on how plant odour plumes (POPs) affect olfactory searching by an insect for its host plants. The primary objective of this review is to examine the role of POPs in the attraction of insects. First, we consider parameters of an odour source and the environment which determine the size, shape and structure of an odour plume, and we apply that knowledge to POPs. Second, we compare characteristics of insect pheromonal plumes and POPs. We propose a 'POP concept' for the olfactory orientation of insects to plants. We suggest that: (i) an insect recognises a POP by means of plant volatile components that are encountered in concentrations higher than a threshold detection limit and that occur in a qualitative and quantitative blend indicating a resource; (ii) perception of the fine structure of a POP enables an insect to distinguish a POP from an unspecific odorous background and other interfering plumes; and (iii) an insect can follow several POPs to their sources, and may leave the track of one POP and switch to another one if this conveys a signal with higher reliability or indicates a more suitable resource. The POP concept proposed here may be a useful tool for research in olfactory-mediated plant-insect interactions.

  9. Speech-perception training for older adults with hearing loss impacts word recognition and effort.

    PubMed

    Kuchinsky, Stefanie E; Ahlstrom, Jayne B; Cute, Stephanie L; Humes, Larry E; Dubno, Judy R; Eckert, Mark A

    2014-10-01

    The current pupillometry study examined the impact of speech-perception training on word recognition and cognitive effort in older adults with hearing loss. Trainees identified more words at the follow-up than at the baseline session. Training also resulted in an overall larger and faster peaking pupillary response, even when controlling for performance and reaction time. Perceptual and cognitive capacities affected the peak amplitude of the pupil response across participants but did not diminish the impact of training on the other pupil metrics. Thus, we demonstrated that pupillometry can be used to characterize training-related and individual differences in effort during a challenging listening task. Importantly, the results indicate that speech-perception training not only affects overall word recognition, but also a physiological metric of cognitive effort, which has the potential to be a biomarker of hearing loss intervention outcome.

  10. Test battery for measuring the perception and recognition of facial expressions of emotion

    PubMed Central

    Wilhelm, Oliver; Hildebrandt, Andrea; Manske, Karsten; Schacht, Annekathrin; Sommer, Werner

    2014-01-01

    Despite the importance of perceiving and recognizing facial expressions in everyday life, there is no comprehensive test battery for the multivariate assessment of these abilities. As a first step toward such a compilation, we present 16 tasks that measure the perception and recognition of facial emotion expressions, and data illustrating each task's difficulty and reliability. The scoring of these tasks focuses on either the speed or accuracy of performance. A sample of 269 healthy young adults completed all tasks. In general, accuracy and reaction time measures for emotion-general scores showed acceptable and high estimates of internal consistency and factor reliability. Emotion-specific scores yielded lower reliabilities, yet high enough to encourage further studies with such measures. Analyses of task difficulty revealed that all tasks are suitable for measuring emotion perception and emotion recognition related abilities in normal populations. PMID:24860528

  11. Speech-perception training for older adults with hearing loss impacts word recognition and effort

    PubMed Central

    Kuchinsky, Stefanie E.; Ahlstrom, Jayne B.; Cute, Stephanie L.; Humes, Larry E.; Dubno, Judy R.; Eckert, Mark A.

    2014-01-01

    The current pupillometry study examined the impact of speech-perception training on word recognition and cognitive effort in older adults with hearing loss. Trainees identified more words at the follow-up than at the baseline session. Training also resulted in an overall larger and faster peaking pupillary response, even when controlling for performance and reaction time. Perceptual and cognitive capacities affected the peak amplitude of the pupil response across participants but did not diminish the impact of training on the other pupil metrics. Thus, we demonstrated that pupillometry can be used to characterize training-related and individual differences in effort during a challenging listening task. Importantly, the results indicate that speech-perception training not only affects overall word recognition, but also a physiological metric of cognitive effort, which has the potential to be a biomarker of hearing loss intervention outcome. PMID:24909603

  12. Subjective disturbance of perception is related to facial affect recognition in schizophrenia.

    PubMed

    Comparelli, Anna; De Carolis, Antonella; Corigliano, Valentina; Romano, Silvia; Kotzalidis, Giorgio D; Campana, Chiara; Ferracuti, Stefano; Tatarelli, Roberto; Girardi, Paolo

    2011-10-01

    To examine the relationship between facial affect recognition (FAR) and subjective perceptual disturbances (SPDs), we assessed SPDs in 82 patients with DSM-IV schizophrenia (44 with first-episode psychosis [FEP] and 38 with multiple episodes [ME]) using two subscales of the Frankfurt Complaint Questionnaire (FCQ), WAS (simple perception) and WAK (complex perception). Emotional judgment ability was assessed using Ekman and Friesen's FAR task. Impaired recognition of emotion correlated with scores on the WAS but not on the WAK. The association was significant in the entire group and in the ME group. FAR was more impaired in the ME than in the FEP group. Our findings suggest that there is a relationship between SPDs and FAR impairment in schizophrenia, particularly in multiple-episode patients.

  13. Speech-perception training for older adults with hearing loss impacts word recognition and effort.

    PubMed

    Kuchinsky, Stefanie E; Ahlstrom, Jayne B; Cute, Stephanie L; Humes, Larry E; Dubno, Judy R; Eckert, Mark A

    2014-10-01

    The current pupillometry study examined the impact of speech-perception training on word recognition and cognitive effort in older adults with hearing loss. Trainees identified more words at the follow-up than at the baseline session. Training also resulted in an overall larger and faster peaking pupillary response, even when controlling for performance and reaction time. Perceptual and cognitive capacities affected the peak amplitude of the pupil response across participants but did not diminish the impact of training on the other pupil metrics. Thus, we demonstrated that pupillometry can be used to characterize training-related and individual differences in effort during a challenging listening task. Importantly, the results indicate that speech-perception training not only affects overall word recognition, but also a physiological metric of cognitive effort, which has the potential to be a biomarker of hearing loss intervention outcome. PMID:24909603

  14. Odours reduce the magnitude of object substitution masking for matching visual targets in females.

    PubMed

    Robinson, Amanda K; Laning, Julia; Reinhard, Judith; Mattingley, Jason B

    2016-08-01

    Recent evidence suggests that olfactory stimuli can influence early stages of visual processing, but there has been little focus on whether such olfactory-visual interactions convey an advantage in visual object identification. Moreover, despite evidence that some aspects of olfactory perception are superior in females than males, no study to date has examined whether olfactory influences on vision are gender-dependent. We asked whether inhalation of familiar odorants can modulate participants' ability to identify briefly flashed images of matching visual objects under conditions of object substitution masking (OSM). Across two experiments, we had male and female participants (N = 36 in each group) identify masked visual images of odour-related objects (e.g., orange, rose, mint) amongst nonodour-related distracters (e.g., box, watch). In each trial, participants inhaled a single odour that either matched or mismatched the masked, odour-related target. Target detection performance was analysed using a signal detection (d') approach. In females, but not males, matching odours significantly reduced OSM relative to mismatching odours, suggesting that familiar odours can enhance the salience of briefly presented visual objects. We conclude that olfactory cues exert a subtle influence on visual processes by transiently enhancing the salience of matching object representations. The results add to a growing body of literature that points towards consistent gender differences in olfactory perception. PMID:27306640

  15. Genetic component of identification, intensity and pleasantness of odours: a Finnish family study.

    PubMed

    Knaapila, Antti; Keskitalo, Kaisu; Kallela, Mikko; Wessman, Maija; Sammalisto, Sampo; Hiekkalinna, Tero; Palotie, Aarno; Peltonen, Leena; Tuorila, Hely; Perola, Markus

    2007-05-01

    Although potential odorant receptor genes have been identified, the precise genetic component of perception of odours is still obscure. Although there is some evidence for heritability of a few olfactory-related traits, no genome-wide search for loci harboring underlying genes has been published to date. We performed a genome-wide scan to identify loci affecting the identification, intensity and pleasantness of 12 odours (cinnamon, turpentine, lemon, smoke, chocolate, rose, paint thinner, banana, pineapple, gasoline, soap, onion) using 146 Finnish adults from 26 families. Several of these traits showed heritable variation in the families. Suggestive evidence of linkage was found for the pleasantness of cinnamon odour (h(2)=61%) on chromosome 4q32.3 (multipoint logarithm of the odds (LOD) score 3.01), as well as for the perceived intensity of paint thinner odour (h(2)=31%) on chromosome 2p14 (multipoint LOD score 2.55). As these loci do not contain any known human odorant receptor genes, they may rather harbor genes that affect the central processing than the peripheral detection of the odour signal. Thus, perception of odours is potentially modified by genes other than those encoding odorant receptors. PMID:17342154

  16. What determines human body odour?

    PubMed

    Hamada, Kaoru; Haruyama, Sanehito; Yamaguchi, Takashi; Yamamoto, Kayo; Hiromasa, Kana; Yoshioka, Manabu; Nishio, Daisuke; Nakamura, Motonobu

    2014-05-01

    Human body odour and earwax type are genetically dependent on a single-nucleotide polymorphism (SNP) located in the ABCC11 gene. So far, it still remains to be clear how SNP in the ABCC11 gene is associated with human malodour. In a recent issue of Experimental Dermatology, Baumann et al. propose one of the underlying molecular pathways. Although one of the amino acid conjugated of the odorants, Cys-Gly-3-methyl-3-sulfanylhexanol (3M3SH), was not taken up by the transporter ABCC11, glutathione conjugate of 3MSH (SG-3MSH) was transported by ABCC11. Moreover, SG-3MSH was processed to 3M3SH by γ-glutamyl-transferase 1 (GGT1), which was abundantly expressed in apocrine sweat glands. These findings may pave a way for the pharmacogenetics of human body odour and the development of innovative deodorant products.

  17. Visual Crowding: a fundamental limit on conscious perception and object recognition

    PubMed Central

    Whitney, David; Levi, Dennis M.

    2011-01-01

    Crowding, the inability to recognize objects in clutter, sets a fundamental limit on conscious visual perception and object recognition throughout most of the visual field. Despite how widespread and essential it is to object recognition, reading, and visually guided action, a solid operational definition of what crowding is has only recently become clear. The goal of this review is to provide a broad-based synthesis of the most recent findings in this area, to define what crowding is and is not, and to set the stage for future work that will extend crowding well beyond low-level vision. Here we define five diagnostic criteria for what counts as crowding, and further describe factors that both escape and break crowding. All of these lead to the conclusion that crowding occurs at multiple stages in the visual hierarchy. PMID:21420894

  18. The odour span task: a novel paradigm for assessing working memory in mice.

    PubMed

    Young, Jared W; Kerr, Lorraine E; Kelly, John S; Marston, Hugh M; Spratt, Christopher; Finlayson, Keith; Sharkey, John

    2007-02-01

    Impoverished odour recognition and memory are amongst the earliest symptoms observed in mild cognitive impairment, Alzheimer's disease and schizophrenia, and have been advocated as early disease bio-markers. Although transgenic animals modelling disease pathologies continually emerge, there remains a paucity of tasks to examine olfactory working memory in mice. The present studies describe a mouse odour span task, which assesses the ability to remember increasing numbers of odours. Since caspase-3 is highly expressed throughout the olfactory system, we postulated that mice over-expressing this apoptogenic protein would exhibit impaired performance in the odour span task. Mice over-expressing human caspase-3 (Tg) exhibited age-independent deficits in olfactory working memory (6-18 months) compared with wild-type littermates, requiring longer for task acquisition and exhibiting impaired asymptotic performance, with reduced span lengths, lower accuracy and increased error rates. These impairments appeared to be selective for working memory, as Tg mice had no deficits in odour discriminatory ability or in locomotor measures. Importantly, nicotine, which improves working memory span in man, reversed the deficits exhibited by Tg mice. In conclusion, the mouse odour span task can detect subtle changes in olfactory working memory induced by genetic manipulation and drug administration and therefore should be applied to animal models of neurological disease.

  19. Continuous odour measurement from fattening pig units

    NASA Astrophysics Data System (ADS)

    Romain, Anne-Claude; Nicolas, Jacques; Cobut, Pierre; Delva, Julien; Nicks, Baudouin; Philippe, François-Xavier

    2013-10-01

    A study in experimental slatted-system fattening pig units was conducted with the aim of estimating the odour emission factor (in ou s.pig-1), which can subsequently be used in dispersion models to assess the odour annoyance zone. Dynamic olfactometry measurements carried out at different development stages of pigs showed a logical trend of the mean assessed odour emission factor with the pig mass. However, the variation within the same mass class was much larger than variation between classes. Possible causes of such variation were identified as the evolution of ventilation rate during the day and the circadian rhythm of pig. To be able to monitor continuously the daily variation of the odour, an electronic nose was used with suitable regression model calibrated against olfactometric measurements. After appropriate validation check, the electronic nose proved to be convenient, as a complementary tool to dynamic olfactometry, to record the daily variation of the odour emission factor in the pig barn. It was demonstrated that, in the controlled conditions of the experimental pens, the daily variation of the odour emission rate could be mainly attributed to the sole influence of the circadian rhythm of pig. As a consequence, determining a representative odour emission factor in a real case cannot be based on a snapshot odour sampling.

  20. Odour management and treatment technologies: an overview.

    PubMed

    Schlegelmilch, M; Streese, J; Stegmann, R

    2005-01-01

    There is a large variety of options available for the effective treatment of odorous emissions. The most important physical, chemical and biological treatment processes are shortly described and their favourable applications, as well as their limits, are highlighted. But for a sustainable solution of an industrial odour problem, there is more involved than just the installation of a waste gas treatment system. This article focuses on a general and systematic approach towards extensive odour management. First of all, an odour assessment should be worked out where all actual and potential odour emission sources are recorded and characterised. A special focus should be set on fugitive emissions, which may have an enormous impact on the overall odour problem. They need to be captured before they can be supplied to a treatment system. According to the composition and condition of the waste gases, an appropriate treatment system must be selected. For this purpose, test systems have been developed and are presented in this article.

  1. Neonatal representation of odour objects: distinct memories of the whole and its parts.

    PubMed

    Coureaud, Gérard; Thomas-Danguin, Thierry; Wilson, Donald A; Ferreira, Guillaume

    2014-08-22

    Extraction of relevant information from highly complex environments is a prerequisite to survival. Within odour mixtures, such information is contained in the odours of specific elements or in the mixture configuration perceived as a whole unique odour. For instance, an AB mixture of the element A (ethyl isobutyrate) and the element B (ethyl maltol) generates a configural AB percept in humans and apparently in another species, the rabbit. Here, we examined whether the memory of such a configuration is distinct from the memory of the individual odorants. Taking advantage of the newborn rabbit's ability to learn odour mixtures, we combined behavioural and pharmacological tools to specifically eliminate elemental memory of A and B after conditioning to the AB mixture and evaluate consequences on configural memory of AB. The amnesic treatment suppressed responsiveness to A and B but not to AB. Two other experiments confirmed the specific perception and particular memory of the AB mixture. These data demonstrate the existence of configurations in certain odour mixtures and their representation as unique objects: after learning, animals form a configural memory of these mixtures, which coexists with, but is relatively dissociated from, memory of their elements. This capability emerges very early in life. PMID:24990670

  2. Integrated odour modelling for sewage treatment works.

    PubMed

    Gostelow, P; Parsons, S A; Lovell, M

    2004-01-01

    Odours from sewage treatment works are a significant source of environmental annoyance. There is a need for tools to assess the degree of annoyance caused, and to assess strategies for mitigation of the problem. This is the role of odour modelling. Four main stages are important in the development of an odour problem. Firstly, the odorous molecules must be formed in the liquid phase. They must then transfer from the liquid to the gaseous phase. They are then transported through the atmosphere to the population surrounding the odour source, and are then perceived and assessed by that population. Odour modelling as currently practised tends to concentrate on the transportation of odorants through the atmosphere, with the other areas receiving less attention. Instead, odour modelling should consider each stage in an integrated manner. This paper describes the development of integrated odour models for annoyance prediction. The models describe the liquid-phase transformations and emission of hydrogen sulphide from sewage treatment processes. Model output is in a form suitable for integration with dispersion models, the predictions of which can in turn be used to indicate the probability of annoyance. The models have been applied to both hypothetical and real sewage treatment works cases. Simulation results have highlighted the potential variability of emission rates from sewage treatment works, resulting from flow, quality and meteorological variations. Emission rate variations can have significant effects on annoyance predictions, which is an important finding, as they are usually considered to be fixed and only meteorological variations are considered in predicting the odour footprint. Areas for further development of integrated odour modelling are discussed, in particular the search for improved links between analytical and sensory measurements, and a better understanding of dose/response relationships for odour annoyance.

  3. Evaluation of an Odour Emission Factor (OEF) to estimate odour emissions from landfill surfaces

    NASA Astrophysics Data System (ADS)

    Lucernoni, Federico; Tapparo, Federica; Capelli, Laura; Sironi, Selena

    2016-11-01

    Emission factors are fundamental tools for air quality management. Odour Emission Factors (OEFs) can be developed in analogy with the emission factors defined for other chemical compounds, which relate the quantity of a pollutant released to the atmosphere to a given associated activity. Landfills typically represent a common source of odour complaint; for this reason, the development of specific OEFs allowing the estimation of odour emissions from this kind of source would be of great interest both for the landfill design and management. This study proposes an up-to-date methodology for the development of an OEF for the estimation of odour emissions from landfills, thereby focusing on the odour emissions related to the emissions of landfill gas (LFG) from the exhausted landfill surface. The proposed approach is an "indirect" approach based on the quantification of the LFG emissions from methane concentration measurements carried out on an Italian landfill. The Odour Emission Rate (OER) is then obtained by multiplying the emitted gas flow rate by the LFG odour concentration. The odour concentration of the LFG emitted through the landfill surface was estimated by means of an ad hoc correlation investigated between methane concentration and odour concentration. The OEF for the estimation of odour emissions from landfill surfaces was computed, considering the landfill surface as the activity index, as the product between the mean specific LFG flux emitted through the surface resulting from the experimental campaigns, equal to 0.39 l/m2/h, and its odour concentration, which was estimated to be equal to 105‧000 eq. ouE/m3, thus giving an OEF of 0.011 ouE/m2/s. This value, which is considerably lower than those published in previous works, should be considered as an improved estimation based on the most recent developments of the research in the field of odour sampling on surface sources.

  4. Voiced Initial Consonant Perception Deficits in Older Listeners with Hearing Loss and Good and Poor Word Recognition

    ERIC Educational Resources Information Center

    Phillips, Susan L.; Richter, Scott J.; McPherson, David

    2009-01-01

    Purpose: This study examined differences in voiced consonant-vowel (CV) perception in older listeners with normal hearing and in 2 groups of older listeners with matched hearing losses: those with good and those with poor word recognition scores. Method: Thirty-six participants identified CVs from an 8-item display from the natural voiced initial…

  5. Effects of auditory recognition learning on the perception of vocal features in European starlings (Sturnus vulgaris).

    PubMed

    Meliza, C Daniel

    2011-11-01

    Learning to recognize complex sensory signals can change the way they are perceived. European starlings (Sturnus vulgaris) recognize other starlings by their song, which consists of a series of complex, stereotyped motifs. Song recognition learning is accompanied by plasticity in secondary auditory areas, suggesting that perceptual learning is involved. Here, to investigate whether perceptual learning can be observed behaviorally, a same-different operant task was used to measure how starlings perceived small differences in motif structure. Birds trained to recognize conspecific songs were better at detecting variations in motifs from the songs they learned, even though this variation was not directly necessary to learn the associative task. Discrimination also improved as the reference stimulus was repeated multiple times. Perception of the much larger differences between different motifs was unaffected by training. These results indicate that sensory representations of motifs are enhanced when starlings learn to recognize songs. PMID:22087940

  6. Effects of auditory recognition learning on the perception of vocal features in European starlings (Sturnus vulgaris)

    PubMed Central

    Daniel Meliza, C.

    2011-01-01

    Learning to recognize complex sensory signals can change the way they are perceived. European starlings (Sturnus vulgaris) recognize other starlings by their song, which consists of a series of complex, stereotyped motifs. Song recognition learning is accompanied by plasticity in secondary auditory areas, suggesting that perceptual learning is involved. Here, to investigate whether perceptual learning can be observed behaviorally, a same–different operant task was used to measure how starlings perceived small differences in motif structure. Birds trained to recognize conspecific songs were better at detecting variations in motifs from the songs they learned, even though this variation was not directly necessary to learn the associative task. Discrimination also improved as the reference stimulus was repeated multiple times. Perception of the much larger differences between different motifs was unaffected by training. These results indicate that sensory representations of motifs are enhanced when starlings learn to recognize songs. PMID:22087940

  7. Unconscious odour conditioning in human subjects.

    PubMed

    Kirk-Smith, M D; Van Toller, C; Dodd, G H

    1983-01-01

    In the first session, two groups of male and female subjects were given a stressful task involving the completion of eleven WAIS block patterns under time limitations. A low intensity of a neutral odour (TUA) was present for half of the subjects. During a second session several days later, subjects completed a mood rating scale and then entered a room, where the odour of TUA was present, to judge a series of photographs of people and complete a second mood rating scale. During the first session female subjects completed significantly fewer block patterns, and completed fewer correct designs. In the second session, female subjects who had experienced TUA odour in the stress condition showed an increase in anxiety ratings. They also had higher ratings scores when judging the photographs. In contrast, subjects who did not experience odour during the stress session became calmer during the second session. None of the female subjects reported perceiving the odour irn either session. As both pairing and elicitation occurred at low levels of awareness, the study demonstrates how odours might acquire values through pairing with emotionally significant events.

  8. Human body odour, symmetry and attractiveness.

    PubMed

    Rikowski, A; Grammer, K

    1999-05-01

    Several studies have found body and facial symmetry as well as attractiveness to be human mate choice criteria. These characteristics are presumed to signal developmental stability. Human body odour has been shown to influence female mate choice depending on the immune system, but the question of whether smell could signal general mate quality, as do other cues, was not addressed in previous studies. We compared ratings of body odour, attractiveness, and measurements of facial and body asymmetry of 16 male and 19 female subjects. Subjects wore a T-shirt for three consecutive nights under controlled conditions. Opposite-sex raters judged the odour of the T-shirts and another group evaluated portraits of the subjects for attractiveness. We measured seven bilateral traits of the subject's body to assess body asymmetry. Facial asymmetry was examined by distance measurements of portrait photographs. The results showed a significant positive correlation between facial attractiveness and sexiness of body odour for female subjects. We found positive relationships between body odour and attractiveness and negative ones between smell and body asymmetry for males only if female odour raters were in the most fertile phase of their menstrual cycle. The outcomes are discussed in the light of different male and female reproductive strategies.

  9. Human body odour, symmetry and attractiveness.

    PubMed Central

    Rikowski, A; Grammer, K

    1999-01-01

    Several studies have found body and facial symmetry as well as attractiveness to be human mate choice criteria. These characteristics are presumed to signal developmental stability. Human body odour has been shown to influence female mate choice depending on the immune system, but the question of whether smell could signal general mate quality, as do other cues, was not addressed in previous studies. We compared ratings of body odour, attractiveness, and measurements of facial and body asymmetry of 16 male and 19 female subjects. Subjects wore a T-shirt for three consecutive nights under controlled conditions. Opposite-sex raters judged the odour of the T-shirts and another group evaluated portraits of the subjects for attractiveness. We measured seven bilateral traits of the subject's body to assess body asymmetry. Facial asymmetry was examined by distance measurements of portrait photographs. The results showed a significant positive correlation between facial attractiveness and sexiness of body odour for female subjects. We found positive relationships between body odour and attractiveness and negative ones between smell and body asymmetry for males only if female odour raters were in the most fertile phase of their menstrual cycle. The outcomes are discussed in the light of different male and female reproductive strategies. PMID:10380676

  10. Manipulation of body odour alters men's self-confidence and judgements of their visual attractiveness by women.

    PubMed

    Craig Roberts, S; Little, A C; Lyndon, A; Roberts, J; Havlicek, J; Wright, R L

    2009-02-01

    Human body odour is important in modulating self-perception and interactions between individuals. Artificial fragrances have been used for thousands of years to manipulate personal odour, but the nature and extent of influences on person perception are relatively unexplored. Here we test the effects of a double-blind manipulation of personal odour on self-confidence and behaviour. We gave to male participants either an aerosol spray containing a formulation of fragrance and antimicrobial agents or an otherwise identical spray that lacked these active ingredients. Over several days, we found effects between treatment groups on psychometric self-confidence and self-perceived attractiveness. Furthermore, although there was no difference between groups in mean attractiveness ratings of men's photographs by a female panel, the same women judged men using the active spray as more attractive in video-clips, suggesting a behavioural difference between the groups. Attractiveness of an individual male's non-verbal behaviour, independent of structural facial features, was predicted by the men's self-reported proclivity towards the provided deodorant. Our results demonstrate the pervasive influence of personal odour on self-perception, and how this can extend to impressions on others even when these impressions are formed in the absence of odour cues.

  11. Manipulation of body odour alters men's self-confidence and judgements of their visual attractiveness by women.

    PubMed

    Craig Roberts, S; Little, A C; Lyndon, A; Roberts, J; Havlicek, J; Wright, R L

    2009-02-01

    Human body odour is important in modulating self-perception and interactions between individuals. Artificial fragrances have been used for thousands of years to manipulate personal odour, but the nature and extent of influences on person perception are relatively unexplored. Here we test the effects of a double-blind manipulation of personal odour on self-confidence and behaviour. We gave to male participants either an aerosol spray containing a formulation of fragrance and antimicrobial agents or an otherwise identical spray that lacked these active ingredients. Over several days, we found effects between treatment groups on psychometric self-confidence and self-perceived attractiveness. Furthermore, although there was no difference between groups in mean attractiveness ratings of men's photographs by a female panel, the same women judged men using the active spray as more attractive in video-clips, suggesting a behavioural difference between the groups. Attractiveness of an individual male's non-verbal behaviour, independent of structural facial features, was predicted by the men's self-reported proclivity towards the provided deodorant. Our results demonstrate the pervasive influence of personal odour on self-perception, and how this can extend to impressions on others even when these impressions are formed in the absence of odour cues. PMID:19134127

  12. Appetitive floral odours prevent aggression in honeybees.

    PubMed

    Nouvian, Morgane; Hotier, Lucie; Claudianos, Charles; Giurfa, Martin; Reinhard, Judith

    2015-01-01

    Honeybees defend their colonies aggressively against intruders and release a potent alarm pheromone to recruit nestmates into defensive tasks. The effect of floral odours on this behaviour has never been studied, despite the relevance of these olfactory cues for the biology of bees. Here we use a novel assay to investigate social and olfactory cues that drive defensive behaviour in bees. We show that social interactions are necessary to reveal the recruiting function of the alarm pheromone and that specific floral odours-linalool and 2-phenylethanol-have the surprising capacity to block recruitment by the alarm pheromone. This effect is not due to an olfactory masking of the pheromone by the floral odours, but correlates with their appetitive value. In addition to their potential applications, these findings provide new insights about how honeybees make the decision to engage into defence and how conflicting information affects this process.

  13. Fat-borne volatiles and sheepmeat odour.

    PubMed

    Young, O A; Berdagué, J L; Viallon, C; Rousset-Akrim, S; Theriez, M

    1997-02-01

    The effects of lamb age and diet on volatiles from fat are described. Rendered fat from ram lambs raised on ewe's milk then a corn-based diet was compared with that from lambs raised on milk and a pasture of grass/clover, six treatments in all. An additional treatment comprised very old ewes maintained on pasture. Helium-borne volatiles of rendered fat were resolved on a DB5 gas chromatographic column and the mass spectra obtained. Long chain alka(e)nes like neophytadiene were dominant in pasture treatments especially where the lamb growth rate was slow. Branch chain fatty acids (4-methyloctanoic, 4-methylnonanoic and an unidentified acid) were also highest in these treatments. Longer chain aldehydes like 2-undecenal were good indicators of a grain diet. Hexanal, commonly associated with rancid odours, was unaffected by treatment. The diketone 2,3-octanedione was an excellent indicator of a pasture diet, as was 3-methylindole (skatole). Phenols showed complex relationships to treatments, but were generally more common in pasture treatments. Benzenethiol (thiophenol) was unaffected by treatment. Inspection of principal component analysis plots identified 10 volatile compounds as contenders for the cause of sheepmeat odour; branch chain fatty acids were confirmed as the leading chemical class. There were indications that puberty or age caused an increase in the odorous 4-methylnonanoic acid. Animal odour-the odour of confined livestock-was clearly causally linked to 3-methylindole, a rumen breakdown product of tryptophan. 3-Methylindole was also responsible for rancid odour, rather than hexanal and its analogues. A hypothesis is advanced that links 2,3-octanedione formation to the enzyme lipoxygenase and linolenic acid, both abundant in green leafy tissue. Overall, the data confirm that sheepmeat odour/flavour is specifically linked to the branch chain fatty acids, and is probably exacerbated by pasture-derived 3-methylindole and alkyl phenols. PMID:22061302

  14. Differential Odour Coding of Isotopomers in the Honeybee Brain

    PubMed Central

    Paoli, Marco; Anesi, Andrea; Antolini, Renzo; Guella, Graziano; Vallortigara, Giorgio; Haase, Albrecht

    2016-01-01

    The shape recognition model of olfaction maintains that odorant reception probes physicochemical properties such as size, shape, electric charge, and hydrophobicity of the ligand. Recently, insects were shown to distinguish common from deuterated isotopomers of the same odorant, suggesting the involvement of other molecular properties to odorant reception. Via two-photon functional microscopy we investigated how common and deuterated isoforms of natural odorants are coded within the honeybee brain. Our results provide evidence that (i) different isotopomers generate different neuronal activation maps, (ii) isotopomer sensitivity is a general mechanism common to multiple odorant receptors, and (iii) isotopomer specificity is highly consistent across individuals. This indicates that honeybee’s olfactory system discriminates between isotopomers of the same odorant, suggesting that other features, such as molecular vibrations, may contribute to odour signal transduction. PMID:26899989

  15. Preferences of newborn mice for odours indicating closer genetic relatedness: is experience necessary?

    PubMed Central

    Todrank, Josephine; Busquet, Nicolas; Baudoin, Claude; Heth, Giora

    2005-01-01

    Evidence from studies with adult rodents indicates that individual recognition enables distinctions between familiar individuals irrespective of relatedness (but including close kin) and a separate mechanism enables discriminations based on genetic relatedness without prior familiarity. For example, adult mice could assess the extent of their genetic relatedness to unfamiliar individuals using perceptual similarities between their individual odours. The ontogeny of this genetic relatedness assessment mechanism, however, had not been investigated. Here, in two-choice tests, newborn mice differentially preferred odours of more genetically similar lactating females (paternal aunts to unrelated conspecific and conspecific to heterospecific) even without prior direct exposure to adults with the tested genotypes. The results provide a direct demonstration of genetic relatedness assessment abilities in newborns and show that experience with parental odours is not necessary for genetic relatedness distinctions. Future studies will be necessary to determine whether exposure to odours of other foetuses in the womb or littermates shortly after birth affects this genetic relatedness assessment process. PMID:16191620

  16. RecceMan: an interactive recognition assistance for image-based reconnaissance: synergistic effects of human perception and computational methods for object recognition, identification, and infrastructure analysis

    NASA Astrophysics Data System (ADS)

    El Bekri, Nadia; Angele, Susanne; Ruckhäberle, Martin; Peinsipp-Byma, Elisabeth; Haelke, Bruno

    2015-10-01

    This paper introduces an interactive recognition assistance system for imaging reconnaissance. This system supports aerial image analysts on missions during two main tasks: Object recognition and infrastructure analysis. Object recognition concentrates on the classification of one single object. Infrastructure analysis deals with the description of the components of an infrastructure and the recognition of the infrastructure type (e.g. military airfield). Based on satellite or aerial images, aerial image analysts are able to extract single object features and thereby recognize different object types. It is one of the most challenging tasks in the imaging reconnaissance. Currently, there are no high potential ATR (automatic target recognition) applications available, as consequence the human observer cannot be replaced entirely. State-of-the-art ATR applications cannot assume in equal measure human perception and interpretation. Why is this still such a critical issue? First, cluttered and noisy images make it difficult to automatically extract, classify and identify object types. Second, due to the changed warfare and the rise of asymmetric threats it is nearly impossible to create an underlying data set containing all features, objects or infrastructure types. Many other reasons like environmental parameters or aspect angles compound the application of ATR supplementary. Due to the lack of suitable ATR procedures, the human factor is still important and so far irreplaceable. In order to use the potential benefits of the human perception and computational methods in a synergistic way, both are unified in an interactive assistance system. RecceMan® (Reconnaissance Manual) offers two different modes for aerial image analysts on missions: the object recognition mode and the infrastructure analysis mode. The aim of the object recognition mode is to recognize a certain object type based on the object features that originated from the image signatures. The

  17. Impact assessment of odours emitted by a wastewater treatment plant.

    PubMed

    Beghi, Sandra P; Santos, Jane Méri; Reis, Neyval Costa; de Sá, Leandro Melo; Goulart, Elisa Valentim; de Abreu Costa, Elza

    2012-01-01

    Complaints from the Domingos Martins population about sewage odours in the city made the district attorney order an impact assessment of the odours emitted by the city wastewater treatment plant (WWTP). This study comprised various techniques, models and population surveys. In 2007, an odour emission model proved that the main hydrogen sulphide emitter was the aeration tank of the WWTP (13.5 g h(-1)) and such emissions, according to CALPUFF model, should be perceived in the whole Domingos Martins city centre area. In this area, 58% of those interviewed were annoyed by the WWTP odours. However, in 2009, the odour monitoring panel recorded few odour occurrences. A second population survey showed that hereafter only 20% of those interviewed were annoyed by the WWTP emissions. Odour emission and dispersion models run with 2010 data proved a drastic reduction of the WWTP aeration tank emissions and consequently the city centre was not bothered by WWTP emissions anymore. The odour emission reduction was due to the modification of the WWTP aeration tank system. Despite the odour emission reduction, houses located southeast of the WWTP were still annoyed by sewage odours. However, in this part of the town, other sources of sewage odours have been found.

  18. Biotechnology-based odour control: design criteria and performance data.

    PubMed

    Quigley, C; Easter, C; Burrowes, P; Witherspoon, J

    2004-01-01

    As neighbouring areas continue to encroach upon wastewater treatment plants, there is an increasing need for odour control to mitigate potential negative offsite odorous impacts. One technology that is gaining widespread acceptance is biotechnology, which utilises the inherent ability of certain microorganisms to biodegrade offensive odorous compounds. Two main advantages of this form of treatment over other odour control technologies include the absence of hazardous chemicals and relatively low operation and maintenance requirements. The purpose of this paper is to provide information related to odour control design criteria used in sizing/selecting biotechnology-based odour control technologies, and to provide odour removal performance data obtained from several different biotechnology-based odour control systems. CH2M HILL has collected biotechnology-based odour control performance data over the last several years in order to track the continued performance of various biofilters and biotowers over time. Specifically, odour removal performance data have been collected from soil-, organic- and inorganic-media biofilters and inert inorganic media biotowers. Results indicate that biotechnology-based odour control is a viable and consistent technology capable of achieving high removal performance for odour and hydrogen sulphide. It is anticipated that the information presented in this paper will be of interest to anyone involved with odour control technology evaluation/selection or design review.

  19. Biotechnology-based odour control: design criteria and performance data.

    PubMed

    Quigley, C; Easter, C; Burrowes, P; Witherspoon, J

    2004-01-01

    As neighbouring areas continue to encroach upon wastewater treatment plants, there is an increasing need for odour control to mitigate potential negative offsite odorous impacts. One technology that is gaining widespread acceptance is biotechnology, which utilises the inherent ability of certain microorganisms to biodegrade offensive odorous compounds. Two main advantages of this form of treatment over other odour control technologies include the absence of hazardous chemicals and relatively low operation and maintenance requirements. The purpose of this paper is to provide information related to odour control design criteria used in sizing/selecting biotechnology-based odour control technologies, and to provide odour removal performance data obtained from several different biotechnology-based odour control systems. CH2M HILL has collected biotechnology-based odour control performance data over the last several years in order to track the continued performance of various biofilters and biotowers over time. Specifically, odour removal performance data have been collected from soil-, organic- and inorganic-media biofilters and inert inorganic media biotowers. Results indicate that biotechnology-based odour control is a viable and consistent technology capable of achieving high removal performance for odour and hydrogen sulphide. It is anticipated that the information presented in this paper will be of interest to anyone involved with odour control technology evaluation/selection or design review. PMID:15484776

  20. Odour emissions from poultry litter - A review litter properties, odour formation and odorant emissions from porous materials.

    PubMed

    Dunlop, Mark W; Blackall, Patrick J; Stuetz, Richard M

    2016-07-15

    Odour emissions from meat chicken sheds can at times cause odour impacts on surrounding communities. Litter is seen as the primary source of this odour. Formation and emission of odour from meat chicken litter during the grow-out period are influenced by various factors such as litter conditions, the environment, microbial activity, properties of the odorous gases and management practices. Odour emissions vary spatially and temporally. This variability has made it challenging to understand how specific litter conditions contribute to odour emissions from the litter and production sheds. Existing knowledge on odorants, odour formation mechanisms and emission processes that contribute to odour emissions from litter are reviewed. Litter moisture content and water thermodynamics (i.e. water activity, Aw) are also examined as factors that contribute to microbial odour formation, physical litter conditions and the exchange of individual odorant gases at the air-water interface. Substantial opportunities exist for future research on litter conditions and litter formation mechanisms and how these contribute to odour emissions. Closing this knowledge gap will improve management strategies that intercept and interfere with odour formation and emission processes leading to an overall reduction in the potential to cause community impacts. PMID:27111649

  1. The looks of an odour - Visualising neural odour response patterns in real time

    PubMed Central

    2013-01-01

    Background Calcium imaging in insects reveals the neural response to odours, both at the receptor level on the antenna and in the antennal lobe, the first stage of olfactory information processing in the brain. Changes of intracellular calcium concentration in response to odour presentations can be observed by employing calcium-sensitive, fluorescent dyes. The response pattern across all recorded units is characteristic for the odour. Method Previously, extraction of odour response patterns from calcium imaging movies was performed offline, after the experiment. We developed software to extract and to visualise odour response patterns in real time. An adaptive algorithm in combination with an implementation for the graphics processing unit enables fast processing of movie streams. Relying on correlations between pixels in the temporal domain, the calcium imaging movie can be segmented into regions that correspond to the neural units. Results We applied our software to calcium imaging data recorded from the antennal lobe of the honeybee Apis mellifera and from the antenna of the fruit fly Drosophila melanogaster. Evaluation on reference data showed results comparable to those obtained by previous offline methods while computation time was significantly lower. Demonstrating practical applicability, we employed the software in a real-time experiment, performing segmentation of glomeruli - the functional units of the honeybee antennal lobe - and visualisation of glomerular activity patterns. Conclusions Real-time visualisation of odour response patterns expands the experimental repertoire targeted at understanding information processing in the honeybee antennal lobe. In interactive experiments, glomeruli can be selected for manipulation based on their present or past activity, or based on their anatomical position. Apart from supporting neurobiology, the software allows for utilising the insect antenna as a chemosensor, e.g. to detect or to classify odours. PMID

  2. Recent odour regulation developments in Flanders: ambient odour quality standards based on dose-response relationships.

    PubMed

    Van Broeck, G; Van Langenhove, H; Nieuwejaers, B

    2001-01-01

    Until now there has been little uniformity in the approach of odour nuisance problems in Flanders. A switch to a standardised and scientifically underpinned approach is essential and is currently in full development. This paper mainly discusses the results of five year research on odour concentration standard developments in Flanders, executed in the period 1996-2000. The research was focused on five pilot sectors: pig farms, slaughterhouses, paint spray installations, sewage treatment plants and textile plants. The general approach of the method to determine the dose-response relation was found to be sufficient. The methodology used is fully described in the paper presented by Van Broeck and Van Langenhove at the CIWEM and IAWO Joint International Conference on Control and Prevention of Odours in the Water Industry in September 1999. For each location (16 locations in total) an unambiguous dose-response relation could be derived (rising nuisance for rising concentrations). In most cases, a "no effect" level could be determined. The background percentage nuisance fluctuated between 0 and 15%. For the sectors of the slaughterhouses, paint spray installations and sewage treatment plants a no effect level was 0.5, 2.0 and 0.5 sniffing units m(-3) as 98th percentile (sniffing units are odour concentrations measured by means of sniffing measurements on the field) was determined. For the sectors of the textile plants and pig farms, no unambiguous no effect level was found. Currently research is undertaken to translate the no effect levels to odour standards. Other initiatives, taken to underpin the Flemish odour regulations, such as the development of an odour source inventory and a complaint handling system, are also briefly discussed. PMID:11762449

  3. Deficits in audiovisual speech perception in normal aging emerge at the level of whole-word recognition.

    PubMed

    Stevenson, Ryan A; Nelms, Caitlin E; Baum, Sarah H; Zurkovsky, Lilia; Barense, Morgan D; Newhouse, Paul A; Wallace, Mark T

    2015-01-01

    Over the next 2 decades, a dramatic shift in the demographics of society will take place, with a rapid growth in the population of older adults. One of the most common complaints with healthy aging is a decreased ability to successfully perceive speech, particularly in noisy environments. In such noisy environments, the presence of visual speech cues (i.e., lip movements) provide striking benefits for speech perception and comprehension, but previous research suggests that older adults gain less from such audiovisual integration than their younger peers. To determine at what processing level these behavioral differences arise in healthy-aging populations, we administered a speech-in-noise task to younger and older adults. We compared the perceptual benefits of having speech information available in both the auditory and visual modalities and examined both phoneme and whole-word recognition across varying levels of signal-to-noise ratio. For whole-word recognition, older adults relative to younger adults showed greater multisensory gains at intermediate SNRs but reduced benefit at low SNRs. By contrast, at the phoneme level both younger and older adults showed approximately equivalent increases in multisensory gain as signal-to-noise ratio decreased. Collectively, the results provide important insights into both the similarities and differences in how older and younger adults integrate auditory and visual speech cues in noisy environments and help explain some of the conflicting findings in previous studies of multisensory speech perception in healthy aging. These novel findings suggest that audiovisual processing is intact at more elementary levels of speech perception in healthy-aging populations and that deficits begin to emerge only at the more complex word-recognition level of speech signals.

  4. Deficits in audiovisual speech perception in normal aging emerge at the level of whole-word recognition

    PubMed Central

    Stevenson, Ryan A.; Nelms, Caitlin; Baum, Sarah H.; Zurkovsky, Lilia; Barense, Morgan D.; Newhouse, Paul A.; Wallace, Mark T.

    2014-01-01

    Over the next two decades, a dramatic shift in the demographics of society will take place, with a rapid growth in the population of older adults. One of the most common complaints with healthy aging is a decreased ability to successfully perceive speech, particularly in noisy environments. In such noisy environments, the presence of visual speech cues (i.e., lip movements) provide striking benefits for speech perception and comprehension, but previous research suggests that older adults gain less from such audiovisual integration than their younger peers. To determine at what processing level these behavioral differences arise in healthy-aging populations, we administered a speech-in-noise task to younger and older adults. We compared the perceptual benefits of having speech information available in both the auditory and visual modalities and examined both phoneme and whole-word recognition across varying levels of signal-to-noise ratio (SNR). For whole-word recognition, older relative to younger adults showed greater multisensory gains at intermediate SNRs, but reduced benefit at low SNRs. By contrast, at the phoneme level both younger and older adults showed approximately equivalent increases in multisensory gain as SNR decreased. Collectively, the results provide important insights into both the similarities and differences in how older and younger adults integrate auditory and visual speech cues in noisy environments, and help explain some of the conflicting findings in previous studies of multisensory speech perception in healthy aging. These novel findings suggest that audiovisual processing is intact at more elementary levels of speech perception in healthy aging populations, and that deficits begin to emerge only at the more complex, word-recognition level of speech signals. PMID:25282337

  5. Revisiting vocal perception in non-human animals: a review of vowel discrimination, speaker voice recognition, and speaker normalization.

    PubMed

    Kriengwatana, Buddhamas; Escudero, Paola; Ten Cate, Carel

    2014-01-01

    The extent to which human speech perception evolved by taking advantage of predispositions and pre-existing features of vertebrate auditory and cognitive systems remains a central question in the evolution of speech. This paper reviews asymmetries in vowel perception, speaker voice recognition, and speaker normalization in non-human animals - topics that have not been thoroughly discussed in relation to the abilities of non-human animals, but are nonetheless important aspects of vocal perception. Throughout this paper we demonstrate that addressing these issues in non-human animals is relevant and worthwhile because many non-human animals must deal with similar issues in their natural environment. That is, they must also discriminate between similar-sounding vocalizations, determine signaler identity from vocalizations, and resolve signaler-dependent variation in vocalizations from conspecifics. Overall, we find that, although plausible, the current evidence is insufficiently strong to conclude that directional asymmetries in vowel perception are specific to humans, or that non-human animals can use voice characteristics to recognize human individuals. However, we do find some indication that non-human animals can normalize speaker differences. Accordingly, we identify avenues for future research that would greatly improve and advance our understanding of these topics.

  6. Revisiting vocal perception in non-human animals: a review of vowel discrimination, speaker voice recognition, and speaker normalization

    PubMed Central

    Kriengwatana, Buddhamas; Escudero, Paola; ten Cate, Carel

    2015-01-01

    The extent to which human speech perception evolved by taking advantage of predispositions and pre-existing features of vertebrate auditory and cognitive systems remains a central question in the evolution of speech. This paper reviews asymmetries in vowel perception, speaker voice recognition, and speaker normalization in non-human animals – topics that have not been thoroughly discussed in relation to the abilities of non-human animals, but are nonetheless important aspects of vocal perception. Throughout this paper we demonstrate that addressing these issues in non-human animals is relevant and worthwhile because many non-human animals must deal with similar issues in their natural environment. That is, they must also discriminate between similar-sounding vocalizations, determine signaler identity from vocalizations, and resolve signaler-dependent variation in vocalizations from conspecifics. Overall, we find that, although plausible, the current evidence is insufficiently strong to conclude that directional asymmetries in vowel perception are specific to humans, or that non-human animals can use voice characteristics to recognize human individuals. However, we do find some indication that non-human animals can normalize speaker differences. Accordingly, we identify avenues for future research that would greatly improve and advance our understanding of these topics. PMID:25628583

  7. Appetitive floral odours prevent aggression in honeybees

    PubMed Central

    Nouvian, Morgane; Hotier, Lucie; Claudianos, Charles; Giurfa, Martin; Reinhard, Judith

    2015-01-01

    Honeybees defend their colonies aggressively against intruders and release a potent alarm pheromone to recruit nestmates into defensive tasks. The effect of floral odours on this behaviour has never been studied, despite the relevance of these olfactory cues for the biology of bees. Here we use a novel assay to investigate social and olfactory cues that drive defensive behaviour in bees. We show that social interactions are necessary to reveal the recruiting function of the alarm pheromone and that specific floral odours—linalool and 2-phenylethanol—have the surprising capacity to block recruitment by the alarm pheromone. This effect is not due to an olfactory masking of the pheromone by the floral odours, but correlates with their appetitive value. In addition to their potential applications, these findings provide new insights about how honeybees make the decision to engage into defence and how conflicting information affects this process. PMID:26694599

  8. Self-recognition in the perception of actions performed in synchrony with music.

    PubMed

    Sevdalis, Vassilis; Keller, Peter E

    2009-07-01

    This study investigated self-recognition in point-light displays depicting actions performed in synchrony with music. Participants were recorded executing three different actions (dancing, walking, and clapping) and were subsequently required to identify the agent (self versus other) from point-light displays with or without the accompanying music. Results indicate that while recognition accuracy was better than chance for all actions, it was best for the relatively complex dance actions. The presence of music did not affect accuracy, suggesting that self-recognition was based on information about personal movement kinematics rather than individual differences in synchrony between movements and music. PMID:19673830

  9. Calculation of odour emissions from aircraft engines at Copenhagen Airport.

    PubMed

    Winther, Morten; Kousgaard, Uffe; Oxbøl, Arne

    2006-07-31

    In a new approach the odour emissions from aircraft engines at Copenhagen Airport are calculated using actual fuel flow and emission measurements (one main engine and one APU: Auxiliary Power Unit), odour panel results, engine specific data and aircraft operational data for seven busy days. The calculation principle assumes a linear relation between odour and HC emissions. Using a digitalisation of the aircraft movements in the airport area, the results are depicted on grid maps, clearly reflecting aircraft operational statistics as single flights or total activity during a whole day. The results clearly reflect the short-term temporal fluctuations of the emissions of odour (and exhaust gases). Aircraft operating at low engine thrust (taxiing, queuing and landing) have a total odour emission share of almost 98%, whereas the shares for the take off/climb out phases (2%) and APU usage (0.5%) are only marginal. In most hours of the day, the largest odour emissions occur, when the total amount of fuel burned during idle is high. However, significantly higher HC emissions for one specific engine cause considerable amounts of odour emissions during limited time periods. The experimentally derived odour emission factor of 57 OU/mg HC is within the range of 23 and 110 OU/mg HC used in other airport odour studies. The distribution of odour emission results between aircraft operational phases also correspond very well with the results for these other studies. The present study uses measurement data for a representative engine. However, the uncertainties become large when the experimental data is used to estimate the odour emissions for all aircraft engines. More experimental data is needed to increase inventory accuracy, and in terms of completeness it is recommended to make odour emission estimates also for engine start and the fuelling of aircraft at Copenhagen Airport in the future.

  10. Calculation of odour emissions from aircraft engines at Copenhagen Airport.

    PubMed

    Winther, Morten; Kousgaard, Uffe; Oxbøl, Arne

    2006-07-31

    In a new approach the odour emissions from aircraft engines at Copenhagen Airport are calculated using actual fuel flow and emission measurements (one main engine and one APU: Auxiliary Power Unit), odour panel results, engine specific data and aircraft operational data for seven busy days. The calculation principle assumes a linear relation between odour and HC emissions. Using a digitalisation of the aircraft movements in the airport area, the results are depicted on grid maps, clearly reflecting aircraft operational statistics as single flights or total activity during a whole day. The results clearly reflect the short-term temporal fluctuations of the emissions of odour (and exhaust gases). Aircraft operating at low engine thrust (taxiing, queuing and landing) have a total odour emission share of almost 98%, whereas the shares for the take off/climb out phases (2%) and APU usage (0.5%) are only marginal. In most hours of the day, the largest odour emissions occur, when the total amount of fuel burned during idle is high. However, significantly higher HC emissions for one specific engine cause considerable amounts of odour emissions during limited time periods. The experimentally derived odour emission factor of 57 OU/mg HC is within the range of 23 and 110 OU/mg HC used in other airport odour studies. The distribution of odour emission results between aircraft operational phases also correspond very well with the results for these other studies. The present study uses measurement data for a representative engine. However, the uncertainties become large when the experimental data is used to estimate the odour emissions for all aircraft engines. More experimental data is needed to increase inventory accuracy, and in terms of completeness it is recommended to make odour emission estimates also for engine start and the fuelling of aircraft at Copenhagen Airport in the future. PMID:16194561

  11. Adjective-noun order as representational structure: native-language grammar influences perception of similarity and recognition memory.

    PubMed

    Mata, André; Percy, Elise J; Sherman, Steven J

    2014-02-01

    This article describes two experiments linking native-language grammar rules with implications for perception of similarity and recognition memory. In prenominal languages (e.g., English), adjectives usually precede nouns, whereas in postnominal languages (e.g., Portuguese), nouns usually precede adjectives. We explored the influence of such rules upon similarity judgments about, and recognition of, objects with multiple category attributes (one nominal attribute and one adjectival attribute). The results supported the hypothesized primacy effect of native-language word order such that nouns generally carried more weight for Portuguese speakers than for English speakers. This pattern was observed for judgments of similarity (i.e., Portuguese speakers tended to judge objects that shared a noun-designated attribute as more similar than did English speakers), as well as for false alarms in recognition memory (i.e., Portuguese speakers tended to falsely recognize more objects if they possessed a familiar noun attribute, relative to English speakers). The implications of such linguistic effects for the cognition of similarity and memory are discussed.

  12. Reduction of odours in pilot-scale landfill biocovers.

    PubMed

    Capanema, M A; Cabana, H; Cabral, A R

    2014-04-01

    Unpleasant odours generated from waste management facilities represent an environmental and societal concern. This multi-year study documented odour and total reduced sulfur (TRS) abatement in four experimental landfill biocovers installed on the final cover of the Saint-Nicéphore landfill (Canada). Performance was evaluated based on the reduction in odour and TRS concentrations between the raw biogas collected from a dedicated well and the emitted gases at the surface. Odour analyses were carried out by the sensorial technique of olfactometry, whereas TRS analyses followed the pulse fluorescence technique. The large difference of 2-5 orders of magnitude between raw biogas (average odour concentration=2,100,000OUm(-3)) and emitted gases resulted in odour removal efficiencies of close to 100% for all observations. With respect to TRS concentrations, abatement efficiencies were all greater than 95%, with values averaging 21,000ppb of eq. SO2 in the raw biogas. The influence of water infiltration on odour concentrations was documented and showed that lower odour values were obtained when the 48-h accumulated precipitation prior to sampling was higher. PMID:24556264

  13. Reduction of odours in pilot-scale landfill biocovers.

    PubMed

    Capanema, M A; Cabana, H; Cabral, A R

    2014-04-01

    Unpleasant odours generated from waste management facilities represent an environmental and societal concern. This multi-year study documented odour and total reduced sulfur (TRS) abatement in four experimental landfill biocovers installed on the final cover of the Saint-Nicéphore landfill (Canada). Performance was evaluated based on the reduction in odour and TRS concentrations between the raw biogas collected from a dedicated well and the emitted gases at the surface. Odour analyses were carried out by the sensorial technique of olfactometry, whereas TRS analyses followed the pulse fluorescence technique. The large difference of 2-5 orders of magnitude between raw biogas (average odour concentration=2,100,000OUm(-3)) and emitted gases resulted in odour removal efficiencies of close to 100% for all observations. With respect to TRS concentrations, abatement efficiencies were all greater than 95%, with values averaging 21,000ppb of eq. SO2 in the raw biogas. The influence of water infiltration on odour concentrations was documented and showed that lower odour values were obtained when the 48-h accumulated precipitation prior to sampling was higher.

  14. Sign Perception and Recognition in Non-Native Signers of ASL.

    PubMed

    Morford, Jill P; Carlson, Martina L

    2011-01-01

    Past research has established that delayed first language exposure is associated with comprehension difficulties in non-native signers of American Sign Language (ASL) relative to native signers. The goal of the current study was to investigate potential explanations of this disparity: do non-native signers have difficulty with all aspects of comprehension, or are their comprehension difficulties restricted to some aspects of processing? We compared the performance of deaf non-native, hearing L2, and deaf native signers on a handshape and location monitoring and a sign recognition task. The results indicate that deaf non-native signers are as rapid and accurate on the monitoring task as native signers, with differences in the pattern of relative performance across handshape and location parameters. By contrast, non-native signers differ significantly from native signers during sign recognition. Hearing L2 signers, who performed almost as well as the two groups of deaf signers on the monitoring task, resembled the deaf native signers more than the deaf non-native signers on the sign recognition task. The combined results indicate that delayed exposure to a signed language leads to an overreliance on handshape during sign recognition. PMID:21686080

  15. The Central Role of Recognition in Auditory Perception: A Neurobiological Model

    ERIC Educational Resources Information Center

    McLachlan, Neil; Wilson, Sarah

    2010-01-01

    The model presents neurobiologically plausible accounts of sound recognition (including absolute pitch), neural plasticity involved in pitch, loudness and location information integration, and streaming and auditory recall. It is proposed that a cortical mechanism for sound identification modulates the spectrotemporal response fields of inferior…

  16. The other-race effect in perception and recognition: insights from the complete composite task.

    PubMed

    Horry, Ruth; Cheong, Winnee; Brewer, Neil

    2015-04-01

    People are more accurate at recognizing faces of their own race than faces from other races, a phenomenon known as the other-race effect. Other-race effects have also been reported in some perceptual tasks. Across 3 experiments, White and Chinese participants completed recognition tests as well as the complete paradigm of the composite task, which measures participants' abilities to selectively attend to the target region of a face while ignoring the task-irrelevant region of the face. Each task was completed with both own- and other-race faces. At a group level, participants showed significant own-race effects in recognition, but not in the composite task. At an individual difference level, the results provided no support for the hypothesis that a deficit in holistic processing for other-race faces drives the other-race effect in recognition. We therefore conclude that the other-race effect in recognition is not driven by the processes that underpin the composite effect.

  17. Liberated Learning: Analysis of University Students' Perceptions and Experiences with Continuous Automated Speech Recognition

    ERIC Educational Resources Information Center

    Ryba, Ken; McIvor, Tom; Shakir, Maha; Paez, Di

    2006-01-01

    This study examined continuous automated speech recognition in the university lecture theatre. The participants were both native speakers of English (L1) and English as a second language students (L2) enrolled in an information systems course (Total N=160). After an initial training period, an L2 lecturer in information systems delivered three…

  18. Antimicrobial textiles, skin-borne flora and odour.

    PubMed

    Höfer, Dirk

    2006-01-01

    Along with climate and physical activity, textiles have an effect on sweating and the development of odours. Accordingly, textiles inadequately optimized in terms of clothing technology as a result of poorly cut structures or poor materials result in increased sweating and odour. However, the development of body odour itself cannot be avoided, even with optimally designed clothing. Therefore new textiles, 'treated with antimicrobial agents', have been developed, with the aim of reducing odour by decreasing the number of germs on the skin. From the scientific point of view, the interactions between textiles, sweat, skin and skin flora are extremely complex. For this reason, this article explains in more detail the basic principles of odour formation resulting from sweat and how this can be influenced by textiles treated with antimicrobial agents. With reference to the results of recent research, the article looks into questions of how textiles treated with antimicrobial agents have an effect on populations of skin bacteria.

  19. Colour preferences influences odour learning in the hawkmoth, Macroglossum stellatarum

    NASA Astrophysics Data System (ADS)

    Balkenius, Anna; Kelber, Almut

    2006-05-01

    The hummingbird hawkmoth, Macroglossum stellatarum, learns colour fast and reliably. It has earlier been shown to spontaneously feed from odourless artificial flowers. Now, we have studied odour learning. The moths were trained to discriminate feeders of the same colour but marked with different odours. They did not learn to discriminate two natural flower odours when they were presented with the innately preferred colour blue, but they did learn this discrimination combined with yellow or green colours that are less attractive to the moth. The yellow colour could be trained to become as attractive as the innately preferred blue colour and the blue colour could be trained to become less attractive. This is the first proof of odour learning in a diurnal moth. The results show that M. stellatarum can use more than one modality in their foraging behaviour and that the system is plastic. By manipulating the preferences for the different colours, their influence on odour learning could be changed.

  20. Insulin modulates network activity in olfactory bulb slices: impact on odour processing.

    PubMed

    Kuczewski, Nicola; Fourcaud-Trocmé, Nicolas; Savigner, Agnès; Thevenet, Marc; Aimé, Pascaline; Garcia, Samuel; Duchamp-Viret, Patricia; Palouzier-Paulignan, Brigitte

    2014-07-01

    Odour perception depends closely on nutritional status, in animals as in humans. Insulin, the principal anorectic hormone, appears to be one of the major candidates for ensuring the link between olfactory abilities and nutritional status, by modifying processing in the olfactory bulb (OB), one of its main central targets. The present study investigates whether and how insulin can act in OB, by evaluating its action on the main output neurons activities, mitral cells (MCs), in acute rat OB slices. Insulin was found to act at two OB network levels: (1) on MCs, by increasing their excitability, probably by inhibiting two voltage-gated potassium (K(+)) channels; (2) on interneurons by modifying the GABAergic and on glutamatergic synaptic activity impinging on MCs, mainly reducing them. Insulin also altered the olfactory nerve (ON)-evoked excitatory postsynaptic currents in 60% of MCs. Insulin decreased or increased the ON-evoked responses in equal proportion and the direction of its effect depended on the initial neuron ON-evoked firing rate. Indeed, insulin tended to decrease the high and to increase the low ON-evoked firing rates, thereby reducing inter-MC response firing variability. Therefore, the effects of insulin on the evoked firing rates were not carried out indiscriminately in the MC population. By constructing a mathematical model, the impact of insulin complex effects on OB was assessed at the population activity level. The model shows that the reduction of variability across cells could affect MC detection and discrimination abilities, mainly by decreasing and, less frequently, increasing them, depending on odour quality. Thus, as previously proposed, this differential action of insulin on MCs across odours would allow this hormone to put the olfactory function under feeding signal control, given the discerning valence of an odour as a function of nutritional status. PMID:24710056

  1. Pyrazine odour makes visually conspicuous prey aversive.

    PubMed

    Lindström, L; Rowe, C; Guilford, T

    2001-01-22

    Unpalatable insects frequently adopt multimodal signals to ward off predators, incorporating sounds and odours into their colourful displays. Pyrazine is an odour commonly used in insect warning displays, and has previously been shown to elicit unlearned biases against common warning colours, e.g. yellow and red in naive predators. We designed two experiments to test for similar effects of pyrazine on the conspicuousness of prey, perhaps the most ubiquitous aspect of aposematic coloration. In the first experiment, we offered predators (Gallus gallus domesticus) a choice between conspicuous crumbs and cryptic crumbs in the presence or absence of pyrazine. In the second experiment, we manipulated the birds' experience of conspicuous prey during an initial training phase. Only in the presence of pyrazine did birds show a bias against conspicuously coloured food, and this occurred whether or not they had previously experienced food that contrasted with the background. This emergent behaviour relied upon the visual and odorous signal components being presented together. These unlearned, yet hidden, responses against conspicuousness demonstrate that there are initial benefits to prey being conspicuous when the multimodal nature of warning signals is accounted for.

  2. Sing that tune: infants' perception of melody and lyrics and the facilitation of phonetic recognition in songs.

    PubMed

    Lebedeva, Gina C; Kuhl, Patricia K

    2010-12-01

    To better understand how infants process complex auditory input, this study investigated whether 11-month-old infants perceive the pitch (melodic) or the phonetic (lyric) components within songs as more salient, and whether melody facilitates phonetic recognition. Using a preferential looking paradigm, uni-dimensional and multi-dimensional songs were tested; either the pitch or syllable order of the stimuli varied. As a group, infants detected a change in pitch order in a 4-note sequence when the syllables were redundant (experiment 1), but did not detect the identical pitch change with variegated syllables (experiment 2). Infants were better able to detect a change in syllable order in a sung sequence (experiment 2) than the identical syllable change in a spoken sequence (experiment 1). These results suggest that by 11 months, infants cannot "ignore" phonetic information in the context of perceptually salient pitch variation. Moreover, the increased phonetic recognition in song contexts mirrors findings that demonstrate advantages of infant-directed speech. Findings are discussed in terms of how stimulus complexity interacts with the perception of sung speech in infancy. PMID:20472295

  3. Sing that tune: infants' perception of melody and lyrics and the facilitation of phonetic recognition in songs.

    PubMed

    Lebedeva, Gina C; Kuhl, Patricia K

    2010-12-01

    To better understand how infants process complex auditory input, this study investigated whether 11-month-old infants perceive the pitch (melodic) or the phonetic (lyric) components within songs as more salient, and whether melody facilitates phonetic recognition. Using a preferential looking paradigm, uni-dimensional and multi-dimensional songs were tested; either the pitch or syllable order of the stimuli varied. As a group, infants detected a change in pitch order in a 4-note sequence when the syllables were redundant (experiment 1), but did not detect the identical pitch change with variegated syllables (experiment 2). Infants were better able to detect a change in syllable order in a sung sequence (experiment 2) than the identical syllable change in a spoken sequence (experiment 1). These results suggest that by 11 months, infants cannot "ignore" phonetic information in the context of perceptually salient pitch variation. Moreover, the increased phonetic recognition in song contexts mirrors findings that demonstrate advantages of infant-directed speech. Findings are discussed in terms of how stimulus complexity interacts with the perception of sung speech in infancy.

  4. Sing that Tune: Infants’ Perception of Melody and Lyrics and the Facilitation of Phonetic Recognition in Songs

    PubMed Central

    Lebedeva, Gina C.; Kuhl, Patricia K.

    2010-01-01

    To better understand how infants process complex auditory input, this study investigated whether 11-month-old infants perceive the pitch (melodic) or the phonetic (lyric) components within songs as more salient, and whether melody facilitates phonetic recognition. Using a preferential looking paradigm, uni-dimensional and multi-dimensional songs were tested; either the pitch or syllable order of the stimuli varied. As a group, infants detected a change in pitch order in a 4-note sequence when the syllables were redundant (Experiment 1), but did not detect the identical pitch change with variegated syllables (Experiment 2). Infants were better able to detect a change in syllable order in a sung sequence (Experiment 2) than the identical syllable change in a spoken sequence (Experiment 1). These results suggest that by 11 months, infants cannot “ignore” phonetic information in the context of perceptually salient pitch variation. Moreover, the increased phonetic recognition in song contexts mirrors findings that demonstrate advantages of infant-directed speech. Findings are discussed in terms of how stimulus complexity interacts with the perception of sung speech in infancy. PMID:20472295

  5. Three-dimensional object recognition by monocular and multisensory perception: Space robotics application

    NASA Astrophysics Data System (ADS)

    Pampagnin, Luc-Henry

    Three dimensional object recognition by computer vision is studied with particular consideration to modelization and graph utilization. First a polyhedral object is identified and located from one intensity image; the model is known and the object is convex or not. The model consists of a geometrical model and the perspective projection aspect graph. Recognition was based on construction and utilization of the compatibility graph, expressing geometrical and visual constraints between matchings of high level entities (object faces). A multisensory system is described, whose main advantage is the complementarity of different kinds of information, which eliminates the limitations due to the use of one image. The system included a black and white camera and a pan and tilt scanning laser range finder.

  6. Affect and face perception: odors modulate the recognition advantage of happy faces.

    PubMed

    Leppanen, Jukka M; Hietanen, Jari K

    2003-12-01

    Previous choice reaction time studies have provided consistent evidence for faster recognition of positive (e.g., happy) than negative (e.g., disgusted) facial expressions. A predominance of positive emotions in normal contexts may partly explain this effect. The present study used pleasant and unpleasant odors to test whether emotional context affects the happy face advantage. Results from 2 experiments indicated that happiness was recognized faster than disgust in a pleasant context, but this advantage disappeared in an unpleasant context because of the slow recognition of happy faces. Odors may modulate the functioning of those emotion-related brain structures that participate in the formation of the perceptual representations of the facial expressions and in the generation of the conceptual knowledge associated with the signaled emotion.

  7. Kiwifruit Flower Odor Perception and Recognition by Honey Bees, Apis mellifera.

    PubMed

    Twidle, Andrew M; Mas, Flore; Harper, Aimee R; Horner, Rachael M; Welsh, Taylor J; Suckling, David M

    2015-06-17

    Volatile organic compounds (VOCs) from male and female kiwifruit (Actinidia deliciosa 'Hayward') flowers were collected by dynamic headspace sampling. Honey bee (Apis mellifera) perception of the flower VOCs was tested using gas chromatography coupled to electroantennogram detection. Honey bees consistently responded to six compounds present in the headspace of female kiwifruit flowers and five compounds in the headspace of male flowers. Analysis of the floral volatiles by gas chromatography-mass spectrometry and microscale chemical derivatization showed the compounds to be nonanal, 2-phenylethanol, 4-oxoisophorone, (3E,6E)-α-farnesene, (6Z,9Z)-heptadecadiene, and (8Z)-heptadecene. Bees were then trained via olfactory conditioning of the proboscis extension response (PER) to synthetic mixtures of these compounds using the ratios present in each flower type. Honey bees trained to the synthetic mixtures showed a high response to the natural floral extracts, indicating that these may be the key compounds for honey bee perception of kiwifruit flower odor.

  8. Pigeon navigation: exposure to environmental odours prior to release is sufficient for homeward orientation, but not for homing.

    PubMed

    Gagliardo, Anna; Pollonara, Enrica; Wikelski, Martin

    2016-08-15

    The role of environmental olfactory information in pigeon navigation has been extensively studied by analysing vanishing bearing distributions and homing performances of homing pigeons subjected to manipulation of their olfactory perception and/or the olfactory information they were exposed to during transportation and at the release site. However, their behaviour during the homing flight remains undocumented. In this experiment we report the analysis of tracks of birds made anosmic at the release site by washing their olfactory mucosa with zinc sulfate. We thus can assess the role of local odours at the release site as well as the role of environmental odours perceived on the way, far from the release site. We observed that pigeons transported and kept at the release site in purified air and made anosmic at the release site were unable to orient towards home and were impaired at homing. By contrast, pigeons allowed to smell environmental odours during transportation and at the release site, although made anosmic prior to release, displayed unimpaired homeward orientation, but nevertheless showed impaired homing performance. These results are consistent with the view that local odours at the release site are critical for determining the direction of displacement (olfactory map) and suggest that pigeons consult the olfactory map also during their homing flight in order to be able to find their way home. PMID:27284069

  9. Pigeon navigation: exposure to environmental odours prior to release is sufficient for homeward orientation, but not for homing.

    PubMed

    Gagliardo, Anna; Pollonara, Enrica; Wikelski, Martin

    2016-08-15

    The role of environmental olfactory information in pigeon navigation has been extensively studied by analysing vanishing bearing distributions and homing performances of homing pigeons subjected to manipulation of their olfactory perception and/or the olfactory information they were exposed to during transportation and at the release site. However, their behaviour during the homing flight remains undocumented. In this experiment we report the analysis of tracks of birds made anosmic at the release site by washing their olfactory mucosa with zinc sulfate. We thus can assess the role of local odours at the release site as well as the role of environmental odours perceived on the way, far from the release site. We observed that pigeons transported and kept at the release site in purified air and made anosmic at the release site were unable to orient towards home and were impaired at homing. By contrast, pigeons allowed to smell environmental odours during transportation and at the release site, although made anosmic prior to release, displayed unimpaired homeward orientation, but nevertheless showed impaired homing performance. These results are consistent with the view that local odours at the release site are critical for determining the direction of displacement (olfactory map) and suggest that pigeons consult the olfactory map also during their homing flight in order to be able to find their way home.

  10. Abu Dhabi's strategic tunnel enhancement programme: odour extraction system approaches.

    PubMed

    Cowden, Scott; Witherspoon, Jay; Orakzai, Shahzad; Krause, T

    2012-01-01

    The Emirate of Abu Dhabi has experienced tremendous growth since the mid-1970s resulting in significant overloading of its existing sewerage system. Master planning determined that the best long-term wastewater collection and conveyance solution was construction of a deep tunnel sewer system. Implementation of this massive project faced numerous challenges, including the goal of no odours and limited odour control facilities. To accomplish this, the consultant team examined a unique approach of a single odour control system installed at the proposed downstream tunnel pumping station. Rigorous analysis utilising computer-based models confirmed the viability of this approach. However, other approaches including multiple satellite (localised or regional) odour extraction systems were considered. To better understand entrained air forces at vortex drops, and to confirm the preferred odour extraction approach, physical modelling of drop structures and overall tunnel system was implemented. Results and findings concluded that a regional odour extraction system approach was preferred over a single (centralised) extraction approach. This paper focuses on the process of selecting the preferred odour extraction approach and preliminary capacity sizing of regional systems.

  11. Odour emission characteristics of 22 recreational rivers in Nanjing.

    PubMed

    Wan, Yu; Ruan, Xiaohong; Wang, Xinguang; Ma, Qian; Lu, Xiaoming

    2014-10-01

    The odour emission characteristics of 22 recreational rivers in Nanjing were investigated and analysed. Eight odorous compounds (ammonia (NH₃), hydrogen sulphide (H₂S), sulphur dioxide (SO₂), carbon disulphide (CS₂), nitrobenzene (C₆H₅NO₂), aniline (C₆H₅NH₂), dimethylamine (C₂H₇N), and formaldehyde (HCHO)) were measured in odour emission samples collected using a custom-made emission flux hood chamber. The results showed that all odorants were detected in all monitoring rivers. NH₃ was the main odorant, with emission rates ranging from 4.86 to 15.13 μg/min m(2). The total odour emission rate of the Nan River, at 1 427.07 OU/s, was the highest of the all investigated rivers. H₂S, NH₃ and nitrobenzene were three key odour emission contributors according to their contributions to the total odour emission. A correlation analysis of the pollutants showed there was a significant positive correlation between the emission rate of NH₃ and the concentration of ammonia nitrogen (NH₄ (+)-N) and total nitrogen (TN). The H₂S and SO₂ emission rates had a significant positive correlation with sulphides (S(2-)) and available sulphur (AS) in the water and sediment. The content of TN, NH₄(+)-N, S(2-) and AS in the water and sediment affected the concentration of H₂S, SO₂ and NH₃ in the emission gases. NH₄(+)-N, S(2-) and AS are suggested as the key odour control indexes for reducing odours emitted from these recreational rivers. The study provides useful information for effective pollution control, especially for odour emission control for the recreational rivers of the city. It also provides a demonstrate example to show how to monitor and assess a contaminated river when odour emission and its control need to be focused on.

  12. Theory of Mind, Emotion Recognition and Social Perception in Individuals at Clinical High Risk for Psychosis: findings from the NAPLS-2 cohort

    PubMed Central

    Barbato, Mariapaola; Liu, Lu; Cadenhead, Kristin S.; Cannon, Tyrone D.; Cornblatt, Barbara A.; McGlashan, Thomas H.; Perkins, Diana O.; Seidman, Larry J.; Tsuang, Ming T.; Walker, Elaine F.; Woods, Scott W.; Bearden, Carrie E.; Mathalon, Daniel H.; Heinssen, Robert; Addington, Jean

    2015-01-01

    Social cognition, the mental operations that underlie social interactions, is a major construct to investigate in schizophrenia. Impairments in social cognition are present before the onset of psychosis, and even in unaffected first-degree relatives, suggesting that social cognition may be a trait marker of the illness. In a large cohort of individuals at clinical high risk for psychosis (CHR) and healthy controls, three domains of social cognition (theory of mind, facial emotion recognition and social perception) were assessed to clarify which domains are impaired in this population. Six-hundred and seventy-five CHR individuals and 264 controls, who were part of the multi-site North American Prodromal Longitudinal Study, completed The Awareness of Social Inference Test, the Penn Emotion Recognition task, the Penn Emotion Differentiation task, and the Relationship Across Domains, measures of theory of mind, facial emotion recognition, and social perception, respectively. Social cognition was not related to positive and negative symptom severity, but was associated with age and IQ. CHR individuals demonstrated poorer performance on all measures of social cognition. However, after controlling for age and IQ, the group differences remained significant for measures of theory of mind and social perception, but not for facial emotion recognition. Theory of mind and social perception are impaired in individuals at CHR for psychosis. Age and IQ seem to play an important role in the arising of deficits in facial affect recognition. Future studies should examine the stability of social cognition deficits over time and their role, if any, in the development of psychosis.

  13. Kiwifruit Flower Odor Perception and Recognition by Honey Bees, Apis mellifera.

    PubMed

    Twidle, Andrew M; Mas, Flore; Harper, Aimee R; Horner, Rachael M; Welsh, Taylor J; Suckling, David M

    2015-06-17

    Volatile organic compounds (VOCs) from male and female kiwifruit (Actinidia deliciosa 'Hayward') flowers were collected by dynamic headspace sampling. Honey bee (Apis mellifera) perception of the flower VOCs was tested using gas chromatography coupled to electroantennogram detection. Honey bees consistently responded to six compounds present in the headspace of female kiwifruit flowers and five compounds in the headspace of male flowers. Analysis of the floral volatiles by gas chromatography-mass spectrometry and microscale chemical derivatization showed the compounds to be nonanal, 2-phenylethanol, 4-oxoisophorone, (3E,6E)-α-farnesene, (6Z,9Z)-heptadecadiene, and (8Z)-heptadecene. Bees were then trained via olfactory conditioning of the proboscis extension response (PER) to synthetic mixtures of these compounds using the ratios present in each flower type. Honey bees trained to the synthetic mixtures showed a high response to the natural floral extracts, indicating that these may be the key compounds for honey bee perception of kiwifruit flower odor. PMID:26027748

  14. Linking ligand perception by PEPR pattern recognition receptors to cytosolic Ca2+ elevation and downstream immune signaling in plants

    PubMed Central

    Walker, Robin K.; Zhao, Yichen; Berkowitz, Gerald A.

    2012-01-01

    Little is known about molecular steps linking perception of pathogen invasion by cell surface sentry proteins acting as pattern recognition receptors (PRRs) to downstream cytosolic Ca2+ elevation, a critical step in plant immune signaling cascades. Some PRRs recognize molecules (such as flagellin) associated with microbial pathogens (pathogen-associated molecular patterns, PAMPs), whereas others bind endogenous plant compounds (damage-associated molecular patterns, DAMPs) such as peptides released from cells upon attack. This work focuses on the Arabidopsis DAMPs plant elicitor peptides (Peps) and their receptors, PEPR1 and PEPR2. Pep application causes in vivo cGMP generation and downstream signaling that is lost when the predicted PEPR receptor guanylyl cyclase (GC) active site is mutated. Pep-induced Ca2+ elevation is attributable to cGMP activation of a Ca2+ channel. Some differences were identified between Pep/PEPR signaling and the Ca2+-dependent immune signaling initiated by the flagellin peptide flg22 and its cognate receptor Flagellin-sensing 2 (FLS2). FLS2 signaling may have a greater requirement for intracellular Ca2+ stores and inositol phosphate signaling, whereas Pep/PEPR signaling requires extracellular Ca2+. Maximal FLS2 signaling requires a functional Pep/PEPR system. This dependence was evidenced as a requirement for functional PEPR receptors for maximal flg22-dependent Ca2+ elevation, H2O2 generation, defense gene [WRKY33 and Plant Defensin 1.2 (PDF1.2)] expression, and flg22/FLS2-dependent impairment of pathogen growth. In a corresponding fashion, FLS2 loss of function impaired Pep signaling. In addition, a role for PAMP and DAMP perception in bolstering effector-triggered immunity (ETI) is reported; loss of function of either FLS2 or PEPR receptors impaired the hypersensitive response (HR) to an avirulent pathogen. PMID:23150556

  15. Linking ligand perception by PEPR pattern recognition receptors to cytosolic Ca2+ elevation and downstream immune signaling in plants.

    PubMed

    Ma, Yi; Walker, Robin K; Zhao, Yichen; Berkowitz, Gerald A

    2012-11-27

    Little is known about molecular steps linking perception of pathogen invasion by cell surface sentry proteins acting as pattern recognition receptors (PRRs) to downstream cytosolic Ca(2+) elevation, a critical step in plant immune signaling cascades. Some PRRs recognize molecules (such as flagellin) associated with microbial pathogens (pathogen-associated molecular patterns, PAMPs), whereas others bind endogenous plant compounds (damage-associated molecular patterns, DAMPs) such as peptides released from cells upon attack. This work focuses on the Arabidopsis DAMPs plant elicitor peptides (Peps) and their receptors, PEPR1 and PEPR2. Pep application causes in vivo cGMP generation and downstream signaling that is lost when the predicted PEPR receptor guanylyl cyclase (GC) active site is mutated. Pep-induced Ca(2+) elevation is attributable to cGMP activation of a Ca(2+) channel. Some differences were identified between Pep/PEPR signaling and the Ca(2+)-dependent immune signaling initiated by the flagellin peptide flg22 and its cognate receptor Flagellin-sensing 2 (FLS2). FLS2 signaling may have a greater requirement for intracellular Ca(2+) stores and inositol phosphate signaling, whereas Pep/PEPR signaling requires extracellular Ca(2+). Maximal FLS2 signaling requires a functional Pep/PEPR system. This dependence was evidenced as a requirement for functional PEPR receptors for maximal flg22-dependent Ca(2+) elevation, H(2)O(2) generation, defense gene [WRKY33 and Plant Defensin 1.2 (PDF1.2)] expression, and flg22/FLS2-dependent impairment of pathogen growth. In a corresponding fashion, FLS2 loss of function impaired Pep signaling. In addition, a role for PAMP and DAMP perception in bolstering effector-triggered immunity (ETI) is reported; loss of function of either FLS2 or PEPR receptors impaired the hypersensitive response (HR) to an avirulent pathogen.

  16. Interpreting odours in hermit crabs: A comparative study

    NASA Astrophysics Data System (ADS)

    Tricarico, Elena; Breithaupt, Thomas; Gherardi, Francesca

    2011-01-01

    Odours of different sources can indicate to hermit crabs the availability of empty shells, crucial resources for the life cycle of almost all of them. Here, we compared Clibanarius erythropus and Pagurus bernhardus for the intensity of investigative behaviour exhibited towards an empty, well-fitting shell in the presence of (1) plain seawater as control and seawater conditioned by (2) dead and live snails, (3) dead and live conspecifics, (4) live predators, and (5) food. During 10 min of observation, we recorded latency (the time until the first contact with the shell), and the number and duration of shell investigation bouts. The two species behaved similarly when exposed to the odours of food, live snails, and predators, while a more intense shell investigation was induced by dead snail odour in C. erythropus and by dead or live conspecific odour in P. bernhardus. Further studies should investigate the influence of phylogeny and ecology on this interspecific difference.

  17. Identification of chemicals, possibly originating from misuse of refillable PET bottles, responsible for consumer complaints about off-odours in water and soft drinks.

    PubMed

    Widén, H; Leufvén, A; Nielsen, T

    2005-07-01

    Mineral water and soft drinks with a perceptible off-odour were analysed to identify contaminants originating from previous misuse of the refillable polyethylene terephthalate (PET) bottle. Consumers detected the off-odour after opening the bottle and duly returned it with the remaining content to the producers. The contaminants in question had thus been undetected by the in-line detection devices (so-called 'sniffers') that are supposed to reject misused bottles. GC-MS analysis was carried out on the headspace of 31 returned products and their corresponding reference products, and chromatograms were compared to find the possible off-odour compounds. Substances believed to be responsible for the organoleptic change were 2-methoxynaphthalene (10 bottles), dimethyl disulfide (4), anethole (3), petroleum products (4), ethanol with isoamyl alcohol (1) and a series of ethers (1). The mouldy/musty odour (5 bottles) was caused by trichloroanisole in one instance. In some cases, the origins of the off-odours are believed to be previous consumer misuse of food products (liquorice-flavoured alcohol, home-made alcohol containing fusel oil) or non-food products (cleaning products, petroleum products, oral moist snuff and others). The results also apply to 1.5-litre recyclable PET bottles, since the nature and extent of consumer misuse can be expected to be similar for the two bottle types.

  18. Identification of chemicals, possibly originating from misuse of refillable PET bottles, responsible for consumer complaints about off-odours in water and soft drinks.

    PubMed

    Widén, H; Leufvén, A; Nielsen, T

    2005-07-01

    Mineral water and soft drinks with a perceptible off-odour were analysed to identify contaminants originating from previous misuse of the refillable polyethylene terephthalate (PET) bottle. Consumers detected the off-odour after opening the bottle and duly returned it with the remaining content to the producers. The contaminants in question had thus been undetected by the in-line detection devices (so-called 'sniffers') that are supposed to reject misused bottles. GC-MS analysis was carried out on the headspace of 31 returned products and their corresponding reference products, and chromatograms were compared to find the possible off-odour compounds. Substances believed to be responsible for the organoleptic change were 2-methoxynaphthalene (10 bottles), dimethyl disulfide (4), anethole (3), petroleum products (4), ethanol with isoamyl alcohol (1) and a series of ethers (1). The mouldy/musty odour (5 bottles) was caused by trichloroanisole in one instance. In some cases, the origins of the off-odours are believed to be previous consumer misuse of food products (liquorice-flavoured alcohol, home-made alcohol containing fusel oil) or non-food products (cleaning products, petroleum products, oral moist snuff and others). The results also apply to 1.5-litre recyclable PET bottles, since the nature and extent of consumer misuse can be expected to be similar for the two bottle types. PMID:16019844

  19. a New Approach to the Assessment of Odour Nuisance.

    NASA Astrophysics Data System (ADS)

    Beaman, A. L.

    Available from UMI in association with The British Library. After reviewing the current situation with regard to the assessment of odour nuisance, the development of a new approach is presented. Descriptions are given of the new techniques which have been developed for quantifying odour intensity, concentration, hedonic tone and annoyance. Statistical analyses of laboratory and field test data collected using these techniques provided mathematical relationships for the assembly of the odour nuisance assessment model. The nuisance criteria adopted was derived from various guidelines and standards from the U.S. and Europe. For completeness an atmospheric dispersion model was developed for estimating the behaviour of odours downwind of the source. This made it possible to assess the probability of an odour nuisance occurring, using any one of a number of different points of knowledge, e.g. existing or future situations. The assessment method has been tested against independent historical data and been demonstrated to be an effective tool in predicting odour nuisance with a consistency better than any existing method. A listing is provided for a computer program to enable the user to apply the model both quickly and effectively.

  20. [Non-conscious perception of emotional faces affects the visual objects recognition].

    PubMed

    Gerasimenko, N Iu; Slavutskaia, A V; Kalinin, S A; Mikhaĭlova, E S

    2013-01-01

    In 34 healthy subjects we have analyzed accuracy and reaction time (RT) during the recognition of complex visual images: pictures of animals and non-living objects. The target stimuli were preceded by brief presentation of masking non-target ones, which represented drawings of emotional (angry, fearful, happy) or neutral faces. We have revealed that in contrast to accuracy the RT depended on the emotional expression of the preceding faces. RT was significantly shorter if the target objects were paired with the angry and fearful faces as compared with the happy and neutral ones. These effects depended on the category of the target stimulus and were more prominent for objects than for animals. Further, the emotional faces' effects were determined by emotional and communication personality traits (defined by Cattell's Questionnaire) and were clearer defined in more sensitive, anxious and pessimistic introverts. The data are important for understanding the mechanisms of human visual behavior determination by non-consciously processing of emotional information. PMID:23885550

  1. Shape Beyond Recognition: Form-derived Directionality and its Effects on Visual Attention and Motion Perception

    PubMed Central

    Sigurdardottir, Heida M.; Michalak, Suzanne M.; Sheinberg, David L.

    2013-01-01

    The shape of an object restricts its movements and therefore its future location. The rules governing selective sampling of the environment likely incorporate any available data, including shape, that provide information about where important things are going to be in the near future so that the object can be located, tracked, and sampled for information. We asked people to assess in which direction several novel objects pointed or directed them. With independent groups of people, we investigated whether their attention and sense of motion were systematically biased in this direction. Our work shows that nearly any novel object has intrinsic directionality derived from its shape. This shape information is swiftly and automatically incorporated into the allocation of overt and covert visual orienting and the detection of motion, processes which themselves are inherently directional. The observed connection between form and space suggests that shape processing goes beyond recognition alone and may help explain why shape is a relevant dimension throughout the visual brain. PMID:23565670

  2. A perfume odour-sensing system using an array of piezoelectric crystal sensors with plasticized PVC coatings.

    PubMed

    Cao, Z; Lin, H G; Wang, B F; Xu, D; Yu, R Q

    1996-05-01

    Using PVC polymer as membrane matrix and di-n-octylphenyl phosphate (DOPP) as plasticizer, a piezoelectric crystal sensor (PCS) array with 12 adsorptive materials selected from 68 compounds by cluster analysis has been constructed as a perfume odour-sensing system. The frequency shift data obtained from the sensor array responding to four commercial perfume odours are first autoscaled and then treated by principal component analysis. The experimental results show that the plasticized PVC membrane PCS array provides improved performance of pattern recognition compared with the single adsorptive coating PCS array. The frequency shift response characteristics of these sensors have been investigated experimentally. The proposed sensor array has also been applied to the classification of commercial spirituous liquor, wine and soft drink samples, as well as aliphatic alcohol homologues and isomers.

  3. An odorant congruent with a colour cue is selectively perceived in an odour mixture.

    PubMed

    Arao, Mari; Suzuki, Maya; Katayama, Jun'ich; Akihiro, Yagi

    2012-01-01

    Odour identification can be influenced by colour cues. This study examined the mechanism underlying this colour context effect. We hypothesised that a specific odour component congruent with a colour would be selectively perceived in preference to another odour component in a binary odour mixture. We used a ratio estimation method under two colour conditions, a binary odour mixture (experiment 1) and single chemicals presented individually (experiment 2). Each colour was congruent with one of the odour components. Participants judged the perceived mixture ratio in each odour container on which a colour patch was pasted. An influence of colour was not observed when the odour stimulus did not contain the odour component congruent with the colour (experiment 2); however, the odour component congruent with the colour was perceived as more dominant when the odour stimulus did contain the colour-congruent odorant (experiment 1). This pattern indicates that a colour-congruent odour component is selectively perceived in an odour mixture. This finding suggests that colours can enhance the perceptual representation of the colour-associated component in an odour mixture.

  4. Recognition and perception of elder abuse by prehospital and hospital-based care providers.

    PubMed

    Rinker, Austin G

    2009-01-01

    The purposes of this study were to evaluate the extent of exposure, knowledge and attitudes of prehospital care providers (PCPs) and hospital care providers (HCPs) to elder abuse and neglect. A 20-question survey was designed to determine the providers' perception, knowledge and ability to identify patients that were potential victims of elder abuse and/or neglect. The surveys were distributed at four Maryland statewide conferences during 2006. A total of 645 surveys were distributed at the start of the individual conferences and 400 completed surveys were returned. Of the respondents, 272 (68.2%) were PCP (emergency medical services=EMSs) and 127 (31.8%) were HCP. During the past 12 months, 51.3% of those surveyed did not have reason to suspect any patients were exposed to abuse or neglect, although 60.5% admitted little or no contact with the elderly. In an attempt to determine respondent's ability to recognize potential abuse and neglect patients, scenario-type questions were used. Respondents believed a decubital ulcer (bedsore) was a positive indicator (83.5%) of abuse/neglect and 92.8% indicated that the elderly could suffer from injuries similar to "shaken-baby syndrome". When questioned about skin bruises as a possible indicator of abuse, only 69.3% of the respondents identified it as a possible sign of abuse. Seventy-one percent of respondents indicated that burns are not common in the elderly and could be another sign of elder abuse. One-in-three providers indicated they would suspect other reasons (dementia, depression, etc.) for the report of a sexual assault in an elderly patient. Eighty-nine percent of providers were aware that healthcare providers in the State of Maryland are required to report suspected elder and vulnerable patient abuse and/or neglect to law enforcement or social services' agencies. When asked to define elder abuse as a medical or social problem, 25.0% of providers stated that it was a social problem. Over 95% of the providers

  5. Responses of tadpoles to hybrid predator odours: strong maternal signatures and the potential risk/response mismatch.

    PubMed

    Chivers, Douglas P; Mathiron, Anthony; Sloychuk, Janelle R; Ferrari, Maud C O

    2015-06-22

    Previous studies have established that when a prey animal knows the identity of a particular predator, it can use this knowledge to make an 'educated guess' about similar novel predators. Such generalization of predator recognition may be particularly beneficial when prey are exposed to introduced and invasive species of predators or hybrids. Here, we examined generalization of predator recognition for woodfrog tadpoles exposed to novel trout predators. Tadpoles conditioned to recognize tiger trout, a hybrid derived from brown trout and brook trout, showed generalization of recognition of several unknown trout odours. Interestingly, the tadpoles showed stronger responses to odours of brown trout than brook trout. In a second experiment, we found that tadpoles trained to recognize brown trout showed stronger responses to tiger trout than those tadpoles trained to recognize brook trout. Given that tiger trout always have a brown trout mother and a brook trout father, these results suggest a strong maternal signature in trout odours. Tadpoles that were trained to recognize both brown trout and brook trout showed stronger response to novel tiger trout than those trained to recognize only brown trout or only brook trout. This is consistent with a peak shift in recognition, whereby cues that are intermediate between two known cues evoke stronger responses than either known cue. Given that our woodfrog tadpoles have no evolutionary or individual experience with trout, they have no way of knowing whether or not brook trout, brown trout or tiger trout are more dangerous. The differential intensity of responses that we observed to hybrid trout cues and each of the parental species indicates that there is a likely mismatch between risk and anti-predator response intensity. Future work needs to address the critical role of prey naivety on responses to invasive and introduced hybrid predators.

  6. Large-Corpus Phoneme and Word Recognition and the Generality of Lexical Context in CVC Word Perception

    ERIC Educational Resources Information Center

    Gelfand, Jessica T.; Christie, Robert E.; Gelfand, Stanley A.

    2014-01-01

    Purpose: Speech recognition may be analyzed in terms of recognition probabilities for perceptual wholes (e.g., words) and parts (e.g., phonemes), where j or the j-factor reveals the number of independent perceptual units required for recognition of the whole (Boothroyd, 1968b; Boothroyd & Nittrouer, 1988; Nittrouer & Boothroyd, 1990). For…

  7. Food Preference and Appetite after Switching between Sweet and Savoury Odours in Women

    PubMed Central

    Ramaekers, Mariëlle G.; Luning, Pieternel A.; Lakemond, Catriona M. M.; van Boekel, Martinus A. J. S.; Gort, Gerrit; Boesveldt, Sanne

    2016-01-01

    Background Exposure to food odours increases the appetite for congruent foods and decreases the appetite for incongruent foods. However, the effect of exposure to a variety of food odours, as often occurs in daily life, is unknown. Objective Investigate how switching between sweet and savoury odours affects the appetite for sweet and savoury products. Design Thirty women (age: 18-45y; BMI: 18.5-25kg/m2) intensely smelled the contents of cups filled with banana, meat or water (no-odour) in a within-subject design with four combinations: no-odour/banana, no-odour/meat, meat/banana and banana/meat. Participants received one combination per test day. In each combination, two cups with different fillings were smelled for five minutes after each other. Treatment order was balanced as much as possible. The effects of previous exposure and current odour on the appetite for (in)congruent sweet and savoury products, and odour pleasantness were analysed. A change from meat to banana odour or banana to meat odour was referred to as switch, whereas a change from no-odour to meat odour or no-odour to banana odour was no-switch. Results The current odour (P<0.001), as opposed to the previous exposure (P = 0.71), determined the appetite for (in)congruent sweet and savoury products, already one minute after a switch between sweet and savoury odours. The pleasantness of the odour decreased during odour exposure (P = 0.005). Conclusions After a switch, the appetite for specific products quickly adjusted to the new odour and followed the typical pattern as found during odour exposure in previous studies. Interestingly, the appetite for the smelled food remained elevated during odour exposure, known as sensory-specific appetite, whereas the pleasantness of the odour decreased over time, previously termed olfactory sensory-specific satiety. This seeming contradiction may result from different mechanisms underlying the odour-induced anticipation of food intake versus the decrease in

  8. Elimination of seaweed odour and its effect on antioxidant activity

    NASA Astrophysics Data System (ADS)

    Keyimu, Xiren Guli; Abdullah, Aminah

    2014-09-01

    The objectives of this study were to determine the most effective method to remove odour from Sargassum muticum seaweeds and studied their antioxidant properties. Ten grams of wet seaweeds (10 grams dried seaweeds soaked in 100 ml water for 2 hours) were soaked in 100 mL of 1%, 3% and 5% of gum Arabic, rice flour, lemon juice, respectively, and 1% of vinegar. There effect of each treatment on antioxidant level were determined by using the total phenolic content (TPC), free radical scavenging ability expressed as a DPPH value, and oxygen radical absorbance capacity (ORAC) and compared to control seaweeds sample (soaked in water only). For sensory attribute, seven trained panellists were asked to evaluate the fishy odour of 11 treated seaweed samples. The fishy odour characteristics and antioxidant activity of treated seaweeds were compared against the control sample (soaked seaweeds), and subjected to statistical analysis. Results showed that 3% and 5% lemon juice and 5% rice flour were able to eliminate the fishy odour of seaweed. However, the antioxidant activity was significantly higher (P<0.05) only for seaweed treated with 5% lemon juice compared to other treatments. Therefore, 5% of lemon juice-treated seaweeds contained the least fishy odour and retained the highest antioxidant activity.

  9. Recent developments in the analysis of musty odour compounds in water and wine: A review.

    PubMed

    Callejón, R M; Ubeda, C; Ríos-Reina, R; Morales, M L; Troncoso, A M

    2016-01-01

    One of the most common taints in foods is a musty or earthy odour, which is commonly associated with the activity of microorganisms. Liquid foods, particularly wine and water, can be affected by this defect due to the presence of certain aromatic organic compounds at very low concentrations (ng/L) consistent with human threshold perception levels. The volatile compounds responsible for a mouldy off-aroma include approximately 20 compounds, namely, haloanisoles, geosmin, 2-methylisoborneol, several alkyl-methoxypyrazines, 1-octen-3-ol, 1-octen-3-one, trans-octenol, 3-octanone, fenchol and fenchone. Methods for determining these very low concentrations of odour compounds must be extremely sensitive and selective with efficient preconcentration treatments. A number of extraction techniques based on LLME (liquid-liquid microextraction), SPME (solid-phase microextraction) or SBSE (stir-bar sorptive extraction) can be applied and should be selected on a case-by-case basis. Moreover, recent developments in GC instrumentation coupled to different detection systems can effectively increase the selectivity and sensitivity of the analysis of target compounds. PMID:26372442

  10. Identification of plant odours activating receptor neurones in the weevil Pissodes notatus F. (Coleoptera, Curculionidae).

    PubMed

    Bichão, H; Borg-Karlson, A-K; Araújo, J; Mustaparta, H

    2003-03-01

    Plants release complex mixtures of volatiles important in the interaction with insects and other organisms. In the search for compounds that contribute to the perception of odour quality in the weevil Pissodes notatus, single olfactory receptor neurones on the antennae were screened for sensitivity to naturally produced plant volatiles by the use of gas chromatography linked to single cell recordings. We here present 60 olfactory neurones responding to 25 of the numerous compounds released by host and non-host plants. All the neurones show high selectivity and are classified into 12 distinct types. The two most abundant types respond to alpha-pinene, beta-pinene, and 3-carene ( n=17), and to isopinocamphone and pinocamphone ( n=17), respectively. Other neurone types respond to limonene ( n=9), beta-phellandrene ( n=3), and fenchone ( n=4). Responses to beta-caryophyllene ( n=1) and to ethanol ( n=4) are also shown. Except for two pairs, the neurone types do not show overlap of the molecular receptive range. The active compounds are present in the host, Pinus pinaster, as well as in non-hosts, supporting the idea that plant odour quality is mediated by the ratio of the compounds rather than specific odorants.

  11. An electronic nose for odour annoyance assessment

    NASA Astrophysics Data System (ADS)

    Francesco, Fabio Di; Lazzerini, Beatrice; Marcelloni, Francesco; Pioggia, Giovanni

    Although in most cases annoying atmospheric emissions do not menace public health, they are less and less tolerated because of the effects on quality of life. Several approaches have been proposed to face this problem but none of them offers a completely satisfying solution. The development of electronic noses, which promise to mimic human sense of smell by means of a sensor array and a pattern recognition model, offers new interesting perspectives. In this paper, an electronic nose based on conducting polymer sensors and a fuzzy logic-based pattern recognition system is tested with waste water samples, obtaining 87% recognition rate on the test set. Current limits of this new technology are discussed and a strategy for their overcoming is proposed.

  12. PTR-MS monitoring of odour emissions from composting plants

    NASA Astrophysics Data System (ADS)

    Biasioli, Franco; Gasperi, Flavia; Odorizzi, Gino; Aprea, Eugenio; Mott, Daniela; Marini, Federico; Autiero, Gianmarco; Rotondo, Giampaolo; Märk, Tilmann D.

    2004-12-01

    We studied the possibility of monitoring with proton transfer reaction-mass spectrometry (PTR-MS) odours emitted in various situations related to composting plants of municipal solid waste (MSW), i.e., waste storage, waste management, and biofilters. Comparison of PTR-MS volatile profiles of the gaseous mixtures entering and exiting a biofilter suggests the possibility of fast and reliable monitoring biofilter efficiency. Moreover, we investigated the relationships between the olfactometric assessment of odour concentration and PTR-MS spectral line intensity finding a positive correlation between the former and several masses and their overall intensity. The application of multivariate calibration methods allows to determine odour concentrations based only on PTR-MS instrumental data. The possibility of avoiding the use of time consuming and expensive olfactometric methods and applications in monitoring waste treatments plants and, in particular, of biofilters is suggested.

  13. The odour of digested sewage sludge--determination and its abatement by air stripping.

    PubMed

    Winter, P; Jones, N; Asaadi, M; Bowman, L

    2004-01-01

    This paper describes a project to investigate the odour of sewage sludge after anaerobic digestion. The impact of air stripping on the odour of liquid sludge and on the quality of the dewatered product was evaluated at a full-scale sludge treatment installation. A continuous and a batch air-stripping mode were tested. Odour samples were collected during air stripping from the liquid sludge and from the biosolids surface during long term storage. The biosolids were also analysed for hedonic tone and for their potential odour expressed as an odour unit per unit mass. The odour emission profiles for continuous and batch air stripping demonstrated a reduction in the overall (time weighted) emissions during a 24 hr-period compared with emissions from the quiescent liquid storage tank. The averaged specific odour emission rate (Esp) of the biosolids derived from the continuous process was only 13% of the Esp of the biosolids derived from unaerated liquid sludge during the first month of storage. The results of the total potential odour and the hedonic tone of the biosolids underpin the beneficial effects of the air stripping. Odour dispersion modelling showed a noticeable reduction in overall odour impact from the sludge centre when air stripping was applied. The reduction was primarily associated with the reduced odour from stockpiled biosolids. The continuous air-stripping mode appeared to provide the greatest benefits in terms of odour impact from site operations.

  14. Learning to distinguish between predators and non-predators: understanding the critical role of diet cues and predator odours in generalisation

    PubMed Central

    Mitchell, Matthew D.; Chivers, Douglas P.; McCormick, Mark I.; Ferrari, Maud C.O.

    2015-01-01

    It is critical for prey to recognise predators and distinguish predators from non-threatening species. Yet, we have little understanding of how prey develop effective predator recognition templates. Recent studies suggest that prey may actually learn key predator features which can be used to recognise novel species with similar characteristics. However, non-predators are sometimes mislabelled as predators when generalising recognition. Here, we conduct the first comprehensive investigation of how prey integrate information on predator odours and predator diet cues in generalisation, allowing them to discriminate between predators and non-predators. We taught lemon damselfish to recognise a predator fed a fish diet, and tested them for their response to the known predator and a series of novel predators (fed fish diet) and non-predators (fed squid diet) distributed across a phylogenetic gradient. Our findings show that damselfish distinguish between predators and non-predators when generalising recognition. Additional experiments revealed that generalised recognition did not result from recognition of predator odours or diet cues, but that damselfish based recognition on what they learned during the initial conditioning. Incorporating multiple sources of information enables prey to develop highly plastic and accurate recognition templates that will increase survival in patchy environments where they have little prior knowledge. PMID:26358861

  15. Livestock odours and quality of life of neighbouring residents.

    PubMed

    Radon, Katja; Peters, Astrid; Praml, Georg; Ehrenstein, Vera; Schulze, Anja; Hehl, Oliver; Nowak, Dennis

    2004-01-01

    Neighbours of intensive livestock production facilities frequently complain of odour annoyance. They are also concerned about potential negative health effects of environmental exposures to livestock emissions. Quality of life (QoL) was assessed in residents of a rural community neighbouring an area with high concentration of animal farms. A postal cross-sectional survey was carried out among the 4,537 residents, aged 18-44 years. Of these, 3,112 (69 %) responded to questions on annoyance by livestock odours (4-point scale), on QoL (assessed by the short form 12, SF-12), and on potential confounders (age, gender, respiratory symptoms, smoking, living on or close to a farm, and employment status). SF-12 scores were available for 2745 (88 %) subjects. Sixty-one percent of the respondents complained about unpleasant odours, 91 % of these accused livestock as source of these odours. Physical and emotional SF-12 scores were inversely related to annoyance scores. Better risk communication might improve QoL in concerned neighbours of intensive livestock production facilities. PMID:15236499

  16. Limitations on representation-mediated potentiation of flavour or odour aversions.

    PubMed

    Holland, Peter C

    2006-02-01

    Odour aversion learning is often potentiated in the presence of flavour stimuli. Establishment of an aversion to an odour is greater when an odour + flavour compound is paired with illness than when the odour alone is paired with illness. Holland (1983) showed that under some circumstances auditory or olfactory stimuli previously paired with flavours may also potentiate odour aversion learning. The present experiments examined limitations on this representation-mediated potentiation of aversion learning. The results indicated that conditioned stimuli (CSs) that activate representations of potentiating cues are themselves immune to potentiation by other CS-activated representations, but remain susceptible to potentiation by their real stimulus associates.

  17. The ovipositional response of the Australian sheep blowfly, Lucilia cuprina, to fleece-rot odours.

    PubMed

    Watts, J E; Merritt, G C; Goodrich, B S

    1981-10-01

    The ovipositional response of Lucilia cuprina flies to odours emanating from fleece-rot lesions of greasy wool in which Pseudomonas aeruginosa bacteria proliferated, was studied. Fractionation of the fleece-rot odours was carried out by bubbling the volatile components through hydrochloric acid and sodium hydroxide solutions to remove basic odours and acidic odours respectively. It was found that the acidic/neutral odours of fleece-rot wool, when perfused into wet, greasy wool stimulated L. cuprina to oviposit. On the other hand, the basic/neutral odours of fleece-rot wool were virtually unattractive to the gravid fly. Similarly, the acidic/neutral odours emanating from fleece-rot lesions of clean wool from which the non-fibre components, wax, suint and epithelial debris, had been removed by scouring, were found to be unattractive to the gravid fly in choice tests. PMID:7337595

  18. General Recognition Theory with Individual Differences: A New Method for Examining Perceptual and Decisional Interactions with an Application to Face Perception

    PubMed Central

    Soto, Fabian A.; Vucovich, Lauren; Musgrave, Robert; Ashby, F. Gregory

    2014-01-01

    A common question in perceptual science is to what extent different stimulus dimensions are processed independently. General recognition theory (GRT) offers a formal framework via which different notions of independence can be defined and tested rigorously, while also dissociating perceptual from decisional factors. This article presents a new GRT model that overcomes several shortcomings with previous approaches, including a clearer separation between perceptual and decisional processes and a more complete description of such processes. The model assumes that different individuals share similar perceptual representations, but vary in their attention to dimensions and in the decisional strategies they use. We apply the model to the analysis of interactions between identity and emotional expression during face recognition. The results of previous research aimed at this problem have been disparate. Participants identified four faces, which resulted from the combination of two identities and two expressions. An analysis using the new GRT model showed a complex pattern of dimensional interactions. The perception of emotional expression was not affected by changes in identity, but the perception of identity was affected by changes in emotional expression. There were violations of decisional separability of expression from identity and of identity from expression, with the former being more consistent across participants than the latter. One explanation for the disparate results in the literature is that decisional strategies may have varied across studies and influenced the results of tests of perceptual interactions, as previous studies lacked the ability to dissociate between perceptual and decisional interactions. PMID:24841236

  19. General recognition theory with individual differences: a new method for examining perceptual and decisional interactions with an application to face perception.

    PubMed

    Soto, Fabian A; Vucovich, Lauren; Musgrave, Robert; Ashby, F Gregory

    2015-02-01

    A common question in perceptual science is to what extent different stimulus dimensions are processed independently. General recognition theory (GRT) offers a formal framework via which different notions of independence can be defined and tested rigorously, while also dissociating perceptual from decisional factors. This article presents a new GRT model that overcomes several shortcomings with previous approaches, including a clearer separation between perceptual and decisional processes and a more complete description of such processes. The model assumes that different individuals share similar perceptual representations, but vary in their attention to dimensions and in the decisional strategies they use. We apply the model to the analysis of interactions between identity and emotional expression during face recognition. The results of previous research aimed at this problem have been disparate. Participants identified four faces, which resulted from the combination of two identities and two expressions. An analysis using the new GRT model showed a complex pattern of dimensional interactions. The perception of emotional expression was not affected by changes in identity, but the perception of identity was affected by changes in emotional expression. There were violations of decisional separability of expression from identity and of identity from expression, with the former being more consistent across participants than the latter. One explanation for the disparate results in the literature is that decisional strategies may have varied across studies and influenced the results of tests of perceptual interactions, as previous studies lacked the ability to dissociate between perceptual and decisional interactions.

  20. A butterfly's chemical key to various ant forts: intersection-odour or aggregate-odour multi-host mimicry?

    NASA Astrophysics Data System (ADS)

    Schlick-Steiner, Birgit C.; Steiner, Florian M.; Höttinger, Helmut; Nikiforov, Alexej; Mistrik, Robert; Schafellner, Christa; Baier, Peter; Christian, Erhard

    Deception is a crucial yet incompletely understood strategy of social parasites. In central Europe, the Mountain Alcon Blue, Maculinea rebeli, a highly endangered butterfly, parasitises several Myrmica ant species. Caterpillars gain access to host nests probably by faking the ants' odour. We analysed gas chromatography-mass spectrometry data of body surface hydrocarbons of pre-adoption and hibernated larvae of Maculinea rebeli and of their host species Myrmica sabuleti and M. schencki. Data were ordinated by different methods, based on similarities in the relative quantities of compounds between chromatograms. The two Myrmica species exhibit species-specific profiles. The Maculinea rebeli pre-adoption larva has a complex profile that simultaneously contains species-specific substances of the two investigated host species. This evidence leads to the interpretation that, in central Europe, Maculinea rebeli is predisposed for multi-host use by the chemical signature of its pre-adoption larva. The Maculinea rebeli larva clearly does not rely on an ``intersection-odour'' of compounds common to all host ant species, but synthesises an ``aggregate-odour'' containing specific compounds of each of the investigated hosts. We term this previously unknown chemical strategy ``aggregate-odour multi-host mimicry''.

  1. Three amino acid residues of an odorant-binding protein are involved in binding odours in Loxostege sticticalis L.

    PubMed

    Yin, J; Zhuang, X; Wang, Q; Cao, Y; Zhang, S; Xiao, C; Li, K

    2015-10-01

    Odorant-binding proteins (OBPs) play an important role in insect olfactory processes and are thought to be responsible for the transport of pheromones and other semiochemicals across the sensillum lymph to the olfactory receptors within the antennal sensilla. As an important general odorant binding protein in the process of olfactory recognition, LstiGOBP1 of Loxostege sticticalis L. has been shown to have good affinity to various plant volatiles. However, the binding specificity of LstiGOBP1 should be further explored in order to better understand the olfactory recognition mechanism of L. sticticalis. In this study, real-time PCR experiments indicated that LstiGOBP1 was expressed primarily in adult antennae. Homology modelling and molecular docking were then conducted on the interactions between LstiGOBP1 and 1-heptanol to understand the interactions between LstiGOBP1 and their ligands. Hydrogen bonds formed by amino acid residues might be crucial for the ligand-binding specificity on molecular docking, a hypothesis that was tested by site-directed mutagenesis. As predicted binding sites for LstiGOBP1, Thr15, Trp43 and Val14 were replaced by alanine to determine the changes in binding affinity. Finally, fluorescence assays revealed that the mutants Thr15 and Trp43 had significantly decreased binding affinity to most odours; in mutants that had two-site mutations, the binding to the six odours that were tested was completely abolished. This result indicates that Thr15 and Trp43 were involved in binding these compounds, possibly by forming multiple hydrogen bonds with the functional groups of the ligands. These results provide new insights into the detailed chemistry of odours' interactions with proteins. PMID:26152502

  2. Serial position functions for recognition of olfactory stimuli.

    PubMed

    Johnson, Andrew J; Miles, Christopher

    2007-10-01

    Two experiments examined item recognition memory for sequentially presented odours. Following a sequence of six odours participants were immediately presented with a series of two-alternative forced-choice (2AFC) test odours. The test pairs were presented in either the same order as learning or the reverse order of learning. Method of testing was either blocked (Experiment 1) or mixed (Experiment 2). Both experiments demonstrated extended recency, with an absence of primacy, for the reverse testing procedure. In contrast, the forward testing procedure revealed a null effect of serial position. The finding of extended recency is inconsistent with the single-item recency predicted by the two-component duplex theory (Phillips & Christie, 1977). We offer an alternative account of the data in which recognition accuracy is better accommodated by the cumulative number of items presented between item learning and item test.

  3. Machine perception

    SciTech Connect

    Not Available

    1982-01-01

    The book is aimed at the level of a graduate student or the practising professional and discusses visual perception by computers. Topics covered include: pattern classification methods; polyhedra scenes; shape analysis and recognition; perception of brightness and colour; edge and curve detection; region segmentation; texture analysis; depth measurement analysis; knowledge-based systems and applications. A subject index is included.

  4. Effects of pH and microbial composition on odour in food waste composting.

    PubMed

    Sundberg, Cecilia; Yu, Dan; Franke-Whittle, Ingrid; Kauppi, Sari; Smårs, Sven; Insam, Heribert; Romantschuk, Martin; Jönsson, Håkan

    2013-01-01

    A major problem for composting plants is odour emission. Slow decomposition during prolonged low-pH conditions is a frequent process problem in food waste composting. The aim was to investigate correlations between low pH, odour and microbial composition during food waste composting. Samples from laboratory composting experiments and two large scale composting plants were analysed for odour by olfactometry, as well as physico-chemical and microbial composition. There was large variation in odour, and samples clustered in two groups, one with low odour and high pH (above 6.5), the other with high odour and low pH (below 6.0). The low-odour samples were significantly drier, had lower nitrate and TVOC concentrations and no detectable organic acids. Samples of both groups were dominated by Bacillales or Actinobacteria, organisms which are often indicative of well-functioning composting processes, but the high-odour group DNA sequences were similar to those of anaerobic or facultatively anaerobic species, not to typical thermophilic composting species. High-odour samples also contained Lactobacteria and Clostridia, known to produce odorous substances. A proposed odour reduction strategy is to rapidly overcome the low pH phase, through high initial aeration rates and the use of additives such as recycled compost.

  5. Olfactory Specific Satiety depends on degree of association between odour and food.

    PubMed

    Stafford, Lorenzo D

    2016-03-01

    The pleasantness of a food odour decreases when that food is eaten to satiety or even smelled for a brief period (Olfactory Specific Satiety, OSS), which suggests that odours signal food variety and encourage approach behaviour toward novel foods. In the study here, we aimed to extend this theory to understand the consequence of manipulating the food consumed and its degree of association to the evaluated odour. We also wished to clarify if these effects related to individual sensitivity to the target odour. In the study here, participants (n = 94) rated the pleasantness of a food odour (isoamyl acetate) and then consumed confectionary that had either Low or High association to that odour or a No food control. This was followed by final pleasantness ratings for the odour and a threshold sensitivity test. Results revealed that in line with OSS, pleasantness decreased in the High association group only. This effect was not dependent on any differences in sensitivity to the target odour. These findings are consistent with OSS, and that this effect likely depends on activation of brain areas related to odour hedonics rather than the degree to which the odour is detected. PMID:26706042

  6. Effects of pH and microbial composition on odour in food waste composting.

    PubMed

    Sundberg, Cecilia; Yu, Dan; Franke-Whittle, Ingrid; Kauppi, Sari; Smårs, Sven; Insam, Heribert; Romantschuk, Martin; Jönsson, Håkan

    2013-01-01

    A major problem for composting plants is odour emission. Slow decomposition during prolonged low-pH conditions is a frequent process problem in food waste composting. The aim was to investigate correlations between low pH, odour and microbial composition during food waste composting. Samples from laboratory composting experiments and two large scale composting plants were analysed for odour by olfactometry, as well as physico-chemical and microbial composition. There was large variation in odour, and samples clustered in two groups, one with low odour and high pH (above 6.5), the other with high odour and low pH (below 6.0). The low-odour samples were significantly drier, had lower nitrate and TVOC concentrations and no detectable organic acids. Samples of both groups were dominated by Bacillales or Actinobacteria, organisms which are often indicative of well-functioning composting processes, but the high-odour group DNA sequences were similar to those of anaerobic or facultatively anaerobic species, not to typical thermophilic composting species. High-odour samples also contained Lactobacteria and Clostridia, known to produce odorous substances. A proposed odour reduction strategy is to rapidly overcome the low pH phase, through high initial aeration rates and the use of additives such as recycled compost. PMID:23122203

  7. Novel Insights into the Ontogeny of Nestmate Recognition in Polistes Social Wasps

    PubMed Central

    Signorotti, Lisa; Cappa, Federico; d’Ettorre, Patrizia; Cervo, Rita

    2014-01-01

    The importance of early experience in animals’ life is unquestionable, and imprinting-like phenomena may shape important aspects of behaviour. Early learning typically occurs during a sensitive period, which restricts crucial processes of information storage to a specific developmental phase. The characteristics of the sensitive period have been largely investigated in vertebrates, because of their complexity and plasticity, both in behaviour and neurophysiology, but early learning occurs also in invertebrates. In social insects, early learning appears to influence important social behaviours such as nestmate recognition. Yet, the mechanisms underlying recognition systems are not fully understood. It is currently believed that Polistes social wasps are able to discriminate nestmates from non-nestmates following the perception of olfactory cues present on the paper of their nest, which are learned during a strict sensitive period, immediately after emergence. Here, through differential odour experience experiments, we show that workers of Polistes dominula develop correct nestmate recognition abilities soon after emergence even in absence of what have been so far considered the necessary cues (the chemicals spread on nest paper). P. dominula workers were exposed for the first four days of adult life to paper fragments from their nest, or from a foreign conspecific nest or to a neutral condition. Wasps were then transferred to their original nests where recognition abilities were tested. Our results show that wasps do not alter their recognition ability if exposed only to nest material, or in absence of nest material, during the early phase of adult life. It thus appears that the nest paper is not used as a source of recognition cues to be learned in a specific time window, although we discuss possible alternative explanations. Our study provides a novel perspective for the study of the ontogeny of nestmate recognition in Polistes wasps and in other social insects

  8. Novel insights into the ontogeny of nestmate recognition in Polistes social wasps.

    PubMed

    Signorotti, Lisa; Cappa, Federico; d'Ettorre, Patrizia; Cervo, Rita

    2014-01-01

    The importance of early experience in animals' life is unquestionable, and imprinting-like phenomena may shape important aspects of behaviour. Early learning typically occurs during a sensitive period, which restricts crucial processes of information storage to a specific developmental phase. The characteristics of the sensitive period have been largely investigated in vertebrates, because of their complexity and plasticity, both in behaviour and neurophysiology, but early learning occurs also in invertebrates. In social insects, early learning appears to influence important social behaviours such as nestmate recognition. Yet, the mechanisms underlying recognition systems are not fully understood. It is currently believed that Polistes social wasps are able to discriminate nestmates from non-nestmates following the perception of olfactory cues present on the paper of their nest, which are learned during a strict sensitive period, immediately after emergence. Here, through differential odour experience experiments, we show that workers of Polistes dominula develop correct nestmate recognition abilities soon after emergence even in absence of what have been so far considered the necessary cues (the chemicals spread on nest paper). P. dominula workers were exposed for the first four days of adult life to paper fragments from their nest, or from a foreign conspecific nest or to a neutral condition. Wasps were then transferred to their original nests where recognition abilities were tested. Our results show that wasps do not alter their recognition ability if exposed only to nest material, or in absence of nest material, during the early phase of adult life. It thus appears that the nest paper is not used as a source of recognition cues to be learned in a specific time window, although we discuss possible alternative explanations. Our study provides a novel perspective for the study of the ontogeny of nestmate recognition in Polistes wasps and in other social insects.

  9. Perception of pathogenic or beneficial bacteria and their evasion of host immunity: pattern recognition receptors in the frontline

    PubMed Central

    Trdá, Lucie; Boutrot, Freddy; Claverie, Justine; Brulé, Daphnée; Dorey, Stephan; Poinssot, Benoit

    2015-01-01

    Plants are continuously monitoring the presence of microorganisms to establish an adapted response. Plants commonly use pattern recognition receptors (PRRs) to perceive microbe- or pathogen-associated molecular patterns (MAMPs/PAMPs) which are microorganism molecular signatures. Located at the plant plasma membrane, the PRRs are generally receptor-like kinases (RLKs) or receptor-like proteins (RLPs). MAMP detection will lead to the establishment of a plant defense program called MAMP-triggered immunity (MTI). In this review, we overview the RLKs and RLPs that assure early recognition and control of pathogenic or beneficial bacteria. We also highlight the crucial function of PRRs during plant-microbe interactions, with a special emphasis on the receptors of the bacterial flagellin and peptidoglycan. In addition, we discuss the multiple strategies used by bacteria to evade PRR-mediated recognition. PMID:25904927

  10. Effects of predator odour on antipredator responses of Nile tilapia.

    PubMed

    Miyai, Caio Akira; Sanches, Fábio Henrique Carretero; Pinho-Neto, Cândido Ferreira; Barreto, Rodrigo Egydio

    2016-10-15

    Several fish species exhibit antipredator responses when exposed to chemicals which indicate risk of predation. One such substance is the scent of a predator (a kairomone) that may induce defensive responses in a potential prey. In the present study, we show that chemical cues (odour) from predator fish induce antipredator and stress responses in Nile tilapia. When exposed to predator odour, Nile tilapia decreased activity and increased ventilation rate (VR), but no increase in plasma levels of cortisol and glucose was found. Although the hypothalamic-pituitary-interrenal axis (HPI axis) was not activated, an increase in ventilation is a fast response which can provide the fish enough oxygen for a 'fight or flight' event when facing a predator. Thus, this respiratory response suggests an anticipated adjustment in order to prepare the body for a defensive response, such as escaping, irrespective of HPI axis activation.

  11. Behavioural correlates of combinatorial versus temporal features of odour codes

    PubMed Central

    Saha, Debajit; Li, Chao; Peterson, Steven; Padovano, William; Katta, Nalin; Raman, Baranidharan

    2015-01-01

    Most sensory stimuli evoke spiking responses that are distributed across neurons and are temporally structured. Whether the temporal structure of ensemble activity is modulated to facilitate different neural computations is not known. Here, we investigated this issue in the insect olfactory system. We found that an odourant can generate synchronous or asynchronous spiking activity across a neural ensemble in the antennal lobe circuit depending on its relative novelty with respect to a preceding stimulus. Regardless of variations in temporal spiking patterns, the activated combinations of neurons robustly represented stimulus identity. Consistent with this interpretation, locusts reliably recognized both solitary and sequential introductions of trained odourants in a quantitative behavioural assay. However, predictable behavioural responses across locusts were observed only to novel stimuli that evoked synchronized spiking patterns across neural ensembles. Hence, our results indicate that the combinatorial ensemble response encodes for stimulus identity, whereas the temporal structure of the ensemble response selectively emphasizes novel stimuli. PMID:25912016

  12. Self-organising sensory maps in odour classification mimicking.

    PubMed

    Davide, F A; Di Natale, C; D'Amico, A

    1995-01-01

    A system for artificial olfaction is introduced, which is composed of a sensor array for gas sensing and a self-organising artificial neural network. A detailed reformulation of the most effective Self-Organising sensory Map (SOM)-based algorithms for odour classification and other applications is provided. An opto-electronic micromachined implementation of the neural network is introduced, which employs a novel hybrid mechanism for activating neural groups, avoiding fabricated cloning templates hardware.

  13. Study of Odours and taste for Space Food

    NASA Astrophysics Data System (ADS)

    Katayama, Naomi; Space Agriculture Task Force; Nakata, Seiichi; Teranishi, Masaaki; Sone, Michihiko; Nakashima, Tsutomu; Hamajima, Nobuyuki; Ito, Yoshihiro

    2012-07-01

    The sense of taste and smell come under some kind of influences in the space environment. In the space, the astronaut was changed their food habits from light taste and smell food to like strong taste and smells food. When an astronaut live in the space comes to have weak bone like osteoporosis. It may become the physiologic condition like the old man on the earth. Therefore this study performed fact-finding of the smell and the taste in the old man on the earth as test bed of astronaut in space. Based on this finding, it was intended to predict the taste and the olfactory change of the astronaut in the space. The study included 179 males and 251 females aged 30-90 years in Yakumo Town, Hokkaido, Japan. Odours were tested using a ``standard odours by odour stick identification''method of organoleptic testing. Taste were tested using a ``standard taste by taste disc identification'' method of chemical testing. Correct answers for identification odours consisted of average 6.0±3.0 in male subjects and average 6.9±2.8 in female subjects. Correct answers for identification of sweet taste consisted of 81% males and 87% females, salty taste consisted of 86% males and 91%, sour taste consisted of 75% males and 78% females, bitter taste consisted of 76% males and 88% females. It became clear that overall approximately 20% were in some kind of abnormality in sense of smell and taste. I want to perform the investigation that continued more in future.

  14. The Facial Expressive Action Stimulus Test. A test battery for the assessment of face memory, face and object perception, configuration processing, and facial expression recognition

    PubMed Central

    de Gelder, Beatrice; Huis in ‘t Veld, Elisabeth M. J.; Van den Stock, Jan

    2015-01-01

    There are many ways to assess face perception skills. In this study, we describe a novel task battery FEAST (Facial Expressive Action Stimulus Test) developed to test recognition of identity and expressions of human faces as well as stimulus control categories. The FEAST consists of a neutral and emotional face memory task, a face and shoe identity matching task, a face and house part-to-whole matching task, and a human and animal facial expression matching task. The identity and part-to-whole matching tasks contain both upright and inverted conditions. The results provide reference data of a healthy sample of controls in two age groups for future users of the FEAST. PMID:26579004

  15. Individual Differences in Language Ability Are Related to Variation in Word Recognition, Not Speech Perception: Evidence from Eye Movements

    ERIC Educational Resources Information Center

    McMurray, Bob; Munson, Cheyenne; Tomblin, J. Bruce

    2014-01-01

    Purpose: The authors examined speech perception deficits associated with individual differences in language ability, contrasting auditory, phonological, or lexical accounts by asking whether lexical competition is differentially sensitive to fine-grained acoustic variation. Method: Adolescents with a range of language abilities (N = 74, including…

  16. Odours detected by rhinophores mediate orientation to flow in the nudibranch mollusc, Tritonia diomedea.

    PubMed

    Wyeth, Russell C; Willows, A O Dennis

    2006-04-01

    Tritonia diomedea is a useful neuroethological model system that can contribute to our understanding of the neural control of navigation. Prior work on both sensory and locomotory systems is complemented by recent field experiments, which concluded that these animals primarily use a combination of odours and water flow as guidance cues. We corroborate these field results by showing similar navigation behaviours in a flow tank. Slugs crawled upstream towards both prey and conspecifics, and turned downstream after crawling into a section of the flow tank downstream of a predator. Controls without upstream odour sources crawled apparently randomly. We then tested whether these behaviours depend on odours detected by the rhinophores. Outflow from a header tank was used to generate prey, predator and unscented control odour plumes in the flow tank. Slugs with rhinophores crawled upstream towards a prey odour plume source, turned downstream in a predator odour plume, and showed no reaction to a control plume. Slugs without rhinophores behaved similarly to controls, regardless of odour plume type. Finally, we used extracellular recordings from the rhinophore nerve to demonstrate that isolated rhinophores are chemosensitive. Afferent activity increased significantly more after application of all three odour types than after unscented control applications. Responses were odour specific. We conclude that rhinophores mediate orientation to flow, and suggest that future work should focus on the integration of mechanosensation and chemosensation during navigation in T. diomedea. PMID:16574804

  17. Odours detected by rhinophores mediate orientation to flow in the nudibranch mollusc, Tritonia diomedea.

    PubMed

    Wyeth, Russell C; Willows, A O Dennis

    2006-04-01

    Tritonia diomedea is a useful neuroethological model system that can contribute to our understanding of the neural control of navigation. Prior work on both sensory and locomotory systems is complemented by recent field experiments, which concluded that these animals primarily use a combination of odours and water flow as guidance cues. We corroborate these field results by showing similar navigation behaviours in a flow tank. Slugs crawled upstream towards both prey and conspecifics, and turned downstream after crawling into a section of the flow tank downstream of a predator. Controls without upstream odour sources crawled apparently randomly. We then tested whether these behaviours depend on odours detected by the rhinophores. Outflow from a header tank was used to generate prey, predator and unscented control odour plumes in the flow tank. Slugs with rhinophores crawled upstream towards a prey odour plume source, turned downstream in a predator odour plume, and showed no reaction to a control plume. Slugs without rhinophores behaved similarly to controls, regardless of odour plume type. Finally, we used extracellular recordings from the rhinophore nerve to demonstrate that isolated rhinophores are chemosensitive. Afferent activity increased significantly more after application of all three odour types than after unscented control applications. Responses were odour specific. We conclude that rhinophores mediate orientation to flow, and suggest that future work should focus on the integration of mechanosensation and chemosensation during navigation in T. diomedea.

  18. Predator odours attract other predators, creating an olfactory web of information.

    PubMed

    Banks, Peter B; Daly, Andrew; Bytheway, Jenna P

    2016-05-01

    Many studies have reported the aversive reactions of prey towards a predator's odour signals (e.g. urine marks), a behaviour widely thought to reduce the risk of predation by the predator. However, because odour signals persist in the environment, they are vulnerable to exploitation and eavesdropping by predators, prey and conspecifics. As such, scent patches created by one species might attract other species interested in information about their enemies. We studied this phenomenon by examining red fox investigation of odours from conspecifics and competing species in order to understand what prey are responding to when avoiding the odours of a predator. Surprisingly, foxes showed limited interest in conspecific odours but were highly interested in the odours of their competitors (wild dogs and feral cats), suggesting that odours are likely to play an important role in mediating competitive interactions. Importantly, our results identify that simple, dyadic interpretations of prey responses to a predator odour (i.e. cat odour = risk of cat encounter = fear of cats) can no longer be assumed in ecological or psychology research. Instead, interactions mediated by olfactory cues are more complex than previously thought and are likely to form a complicated olfactory web of interactions. PMID:27194283

  19. Odours stimulate neuronal activity in the dorsolateral area of the hippocampal formation during path integration.

    PubMed

    Jorge, P E; Phillips, J B; Gonçalves, A; Marques, P A M; Nĕmec, P

    2014-05-22

    The dorsolateral area of the hippocampal formation of birds is commonly assumed to play a central role in processing information needed for geographical positioning and homing. Previous work has interpreted odour-induced activity in this region as evidence for an 'olfactory map'. Here, we show, using c-Fos expression as a marker, that neuronal activation in the dorsolateral area of the hippocampal formation of pigeons is primarily a response to odour novelty, not to the spatial distribution of odour sources that would be necessary for an olfactory map. Pigeons exposed to odours had significantly more neurons activated in this area of the brain than pigeons exposed to filtered air with odours removed. This increased activity was observed only in response to unfamiliar odours. No change in activity was observed when pigeons were exposed to home odours. These findings are consistent with non-home odours activating non-olfactory components of the pigeon's navigation system. The pattern of neuronal activation in the triangular and dorsomedial areas of the hippocampal formation was, by contrast, consistent with the possibility that odours play a role in providing spatial information. PMID:24671977

  20. Odours stimulate neuronal activity in the dorsolateral area of the hippocampal formation during path integration

    PubMed Central

    Jorge, P. E.; Phillips, J. B.; Gonçalves, A.; Marques, P. A. M.; Nĕmec, P.

    2014-01-01

    The dorsolateral area of the hippocampal formation of birds is commonly assumed to play a central role in processing information needed for geographical positioning and homing. Previous work has interpreted odour-induced activity in this region as evidence for an ‘olfactory map’. Here, we show, using c-Fos expression as a marker, that neuronal activation in the dorsolateral area of the hippocampal formation of pigeons is primarily a response to odour novelty, not to the spatial distribution of odour sources that would be necessary for an olfactory map. Pigeons exposed to odours had significantly more neurons activated in this area of the brain than pigeons exposed to filtered air with odours removed. This increased activity was observed only in response to unfamiliar odours. No change in activity was observed when pigeons were exposed to home odours. These findings are consistent with non-home odours activating non-olfactory components of the pigeon's navigation system. The pattern of neuronal activation in the triangular and dorsomedial areas of the hippocampal formation was, by contrast, consistent with the possibility that odours play a role in providing spatial information. PMID:24671977

  1. Influence of gonadal hormones on odours emitted by male meadow voles (Microtus pennsylvanicus).

    PubMed

    Ferkin, M H; Gorman, M R; Zucker, I

    1992-08-01

    Free-living male meadow voles (Microtus pennsylvanicus) emit odours that are attractive to females at the beginning, but not at the end, of the breeding season. The effect of gonadal hormones on female-attractant cues was examined in males born and reared in long (14 h light day-1) and short (10 h light day-1) photoperiods that simulate daylengths in the breeding and nonbreeding seasons, respectively. Gonadectomy affected the attractant properties of odours emitted by long photoperiod, but not short photoperiod, males. Long photoperiod females preferred odours of intact rather than those of gonadectomized long photoperiod males, and odours of gonadectomized long photoperiod males rather than those of intact short photoperiod males. Females did not show a preference between the odours of intact and castrated short photoperiod males. Gonadal hormone replacement in males affected female responses to the odours emitted by long photoperiod, but not short photoperiod, gonadectomized males. Long photoperiod females did not display a preference between odours of intact long photoperiod males and gonadectomized long photoperiod males treated with testosterone or oestradiol. We conclude that in spring and summer gonadal hormones increase attractiveness of male odours; this effect may require aromatization of testosterone to oestradiol. Substrates that control attractiveness of odour cues in male voles appear to be unresponsive to androgens during the nonbreeding season. PMID:1404090

  2. Mental Health Literacy for Anxiety Disorders: How perceptions of symptom severity might relate to recognition of psychological distress

    PubMed Central

    Paulus, Daniel J.; Wadsworth, Lauren Page; Hayes-Skelton, Sarah A.

    2015-01-01

    Purpose Improving mental health literacy is an important consideration when promoting expedient and effective treatment seeking for psychological disorders. Low recognition serves as a barrier to treatment (Coles and Coleman, 2010), and this article examines recognition by lay individuals of severity for three psychological disorders: social anxiety, generalized anxiety, and major depression using a dimensional approach. Design Vignettes of mild/subclinical, moderate, and severe cases of each disorder were rated for severity by a team of expert assessors and 270 participants (mean age = 26.8; 76.7% women). Findings Difference ratings were calculated comparing participants’ responses to scores from the assessors. A within-groups factorial ANOVA with LSD follow-up was performed to examine the effects of Diagnosis and Severity on difference ratings. Both main effects [Diagnosis, F(2, 536)=35.26, Mse=1.24; Severity, F(2, 536)=9.44, Mse=1.93] and the interaction were significant [F(4, 1072)=13.70, Mse=1.13] all p’s < 0.001. Social anxiety cases were underrated in the mild/subclinical and moderate cases, generalized anxiety cases were underrated at all three severities, and major depression cases were overrated at all three severities. Social implications Judgments of severity may underlie the low recognition rates for social anxiety disorder and generalized anxiety disorder. Future efforts should focus on improved recognition and education regarding anxiety disorders in the population, particularly before they become severe. Value This project demonstrates the importance of considering judgments of symptom severity on a continuum, and in a range of cases, rather than just the ability to correctly label symptoms, when determining whether or not people recognize psychological disorders. PMID:26893607

  3. Follow your nose: leaf odour as an important foraging cue for mammalian herbivores.

    PubMed

    Stutz, Rebecca S; Banks, Peter B; Proschogo, Nicholas; McArthur, Clare

    2016-11-01

    Studies of odour-driven foraging by mammals focus on attractant cues emitted by flowers, fruits, and fungi. Yet, the leaves of many plant species worldwide produce odour, which could act as a cue for foraging mammalian herbivores. Leaf odour may thus improve foraging efficiency for such herbivores in many ecosystems by reducing search time, particularly but not only, for plants that are visually obscured. We tested the use of leaf odour by a free-ranging mammalian browser, the swamp wallaby (Wallabia bicolor) to find and browse palatable tree seedlings (Eucalyptus pilularis). Wallabies visited patches non-randomly with respect to the presence of seedlings. In the absence of visual plant cues, they used leaf odour (cut seedlings in vials) to find patches earlier, and visited and investigated them more often than control patches (empty vials), supporting the hypothesis that wallabies used seedling odour to enhance search efficiency. In contrast, the grey kangaroo (Macropus giganteus), a grazer, showed no response to seedling odour. When the availability of seedling visual and olfactory cues was manipulated, wallabies browsed seedlings equally quickly in all treatments: upright (normal cues), pinned to the ground (reduced visual cues), and upright plus pinned seedlings (double olfactory cues). Odour cues play a critical role in food-finding by swamp wallabies, and these animals are finely tuned to detecting these cues with their threshold for detection reached by odours from only a single plant. The global significance of leaf odour in foraging by mammalian herbivores consuming conifers, eucalypts, and other odour-rich species requires greater attention. PMID:27368609

  4. Follow your nose: leaf odour as an important foraging cue for mammalian herbivores.

    PubMed

    Stutz, Rebecca S; Banks, Peter B; Proschogo, Nicholas; McArthur, Clare

    2016-11-01

    Studies of odour-driven foraging by mammals focus on attractant cues emitted by flowers, fruits, and fungi. Yet, the leaves of many plant species worldwide produce odour, which could act as a cue for foraging mammalian herbivores. Leaf odour may thus improve foraging efficiency for such herbivores in many ecosystems by reducing search time, particularly but not only, for plants that are visually obscured. We tested the use of leaf odour by a free-ranging mammalian browser, the swamp wallaby (Wallabia bicolor) to find and browse palatable tree seedlings (Eucalyptus pilularis). Wallabies visited patches non-randomly with respect to the presence of seedlings. In the absence of visual plant cues, they used leaf odour (cut seedlings in vials) to find patches earlier, and visited and investigated them more often than control patches (empty vials), supporting the hypothesis that wallabies used seedling odour to enhance search efficiency. In contrast, the grey kangaroo (Macropus giganteus), a grazer, showed no response to seedling odour. When the availability of seedling visual and olfactory cues was manipulated, wallabies browsed seedlings equally quickly in all treatments: upright (normal cues), pinned to the ground (reduced visual cues), and upright plus pinned seedlings (double olfactory cues). Odour cues play a critical role in food-finding by swamp wallabies, and these animals are finely tuned to detecting these cues with their threshold for detection reached by odours from only a single plant. The global significance of leaf odour in foraging by mammalian herbivores consuming conifers, eucalypts, and other odour-rich species requires greater attention.

  5. Testing Speech Recognition in Spanish-English Bilingual Children with the Computer-Assisted Speech Perception Assessment (CASPA): Initial Report.

    PubMed

    García, Paula B; Rosado Rogers, Lydia; Nishi, Kanae

    2016-01-01

    This study evaluated the English version of Computer-Assisted Speech Perception Assessment (E-CASPA) with Spanish-English bilingual children. E-CASPA has been evaluated with monolingual English speakers ages 5 years and older, but it is unknown whether a separate norm is necessary for bilingual children. Eleven Spanish-English bilingual and 12 English monolingual children (6 to 12 years old) with normal hearing participated. Responses were scored by word, phoneme, consonant, and vowel. Regardless of scores, performance across three signal-to-noise ratio conditions was similar between groups, suggesting that the same norm can be used for both bilingual and monolingual children.

  6. Facial expression of fear in the context of human ethology: Recognition advantage in the perception of male faces.

    PubMed

    Trnka, Radek; Tavel, Peter; Tavel, Peter; Hasto, Jozef

    2015-01-01

    Facial expression is one of the core issues in the ethological approach to the study of human behaviour. This study discusses sex-specific aspects of the recognition of the facial expression of fear using results from our previously published experimental study. We conducted an experiment in which 201 participants judged seven different facial expressions: anger, contempt, disgust, fear, happiness, sadness and surprise (Trnka et al. 2007). Participants were able to recognize the facial expression of fear significantly better on a male face than on a female face. Females also recognized fear generally better than males. The present study provides a new interpretation of this sex difference in the recognition of fear. We interpret these results within the paradigm of human ethology, taking into account the adaptive function of the facial expression of fear. We argue that better detection of fear might be crucial for females under a situation of serious danger in groups of early hominids. The crucial role of females in nurturing and protecting offspring was fundamental for the reproductive potential of the group. A clear decoding of this alarm signal might thus have enabled the timely preparation of females for escape or defence to protect their health for successful reproduction. Further, it is likely that males played the role of guardians of social groups and that they were responsible for effective warnings of the group under situations of serious danger. This may explain why the facial expression of fear is better recognizable on the male face than on the female face.

  7. Awaken olfactory receptors of humans and experimental animals by coffee odourants to induce appetite.

    PubMed

    Dorri, Yaser; Sabeghi, Maryam; Kurien, Biji T

    2007-01-01

    Smell and its mechanism has been of interest to scientists for many years. Smell, not only provides a sensual pleasure of food and perfumes for humans but also reminds us of past memories, thoughts, locations and finally warns of dangers such as fire. One of the uses of coffee beans is on perfume counters, enabling people to distinguish between perfume fragrances. We hypothesize that coffee can be also used to refresh olfactory receptors after cooking, since people usually experience loss of appetite after cooking. We have experienced an increase in appetite, after cooking, by smelling coffee beans. This is probably due to the detachment of food odourants from olfactory receptors by the coffee odourant molecules. We also think that coffee smell could be used in animal research studies, to keep animals healthy by stimulating their appetite. In a recent study, 28 different odourants have been identified from coffee. One or more of these odourants may have strong binding affinity to olfactory receptors which results in detachment of other odourants from the receptors. The high vibration intensity from coffee odourant molecules may cause the detachment of food odourant from olfactory receptors. Another hypothesis might be the unique structure of these coffee odourants. Studies need to be done to investigate the effect of coffee smell on salivary flow and appetite in animals and humans.

  8. Interference competition: odours of an apex predator and conspecifics influence resource acquisition by red foxes.

    PubMed

    Leo, Viyanna; Reading, Richard P; Letnic, Mike

    2015-12-01

    Apex predators can impact smaller predators via lethal effects that occur through direct killing, and non-lethal effects that arise when fear-induced behavioural and physiological changes reduce the fitness of smaller predators. A general outcome of asymmetrical competition between co-existing predator species is that larger predators tend to suppress the abundances of smaller predators. Here, we investigate interference effects that an apex predator, the dingo (Canis dingo), has on the acquisition of food and water by the smaller red fox (Vulpes vulpes), by exposing free-ranging foxes to the odour of dingoes and conspecifics in an arid environment. Using giving-up densities we show that foxes foraged more apprehensively at predator-odour treatments than unscented controls, but their food intake did not differ between dingo- and fox-odour treatments. Using video analysis of fox behaviour at experimental water stations we show that foxes spent more time engaged in exploration behaviour at stations scented with fox odour and spent more time drinking at water stations scented with dingo odour. Our results provide support for the idea that dingo odour exerts a stronger interference effect on foxes than conspecific odour, but suggest that the odours of both larger dingoes and unfamiliar conspecifics curtailed foxes' acquisition of food resources.

  9. Interference competition: odours of an apex predator and conspecifics influence resource acquisition by red foxes.

    PubMed

    Leo, Viyanna; Reading, Richard P; Letnic, Mike

    2015-12-01

    Apex predators can impact smaller predators via lethal effects that occur through direct killing, and non-lethal effects that arise when fear-induced behavioural and physiological changes reduce the fitness of smaller predators. A general outcome of asymmetrical competition between co-existing predator species is that larger predators tend to suppress the abundances of smaller predators. Here, we investigate interference effects that an apex predator, the dingo (Canis dingo), has on the acquisition of food and water by the smaller red fox (Vulpes vulpes), by exposing free-ranging foxes to the odour of dingoes and conspecifics in an arid environment. Using giving-up densities we show that foxes foraged more apprehensively at predator-odour treatments than unscented controls, but their food intake did not differ between dingo- and fox-odour treatments. Using video analysis of fox behaviour at experimental water stations we show that foxes spent more time engaged in exploration behaviour at stations scented with fox odour and spent more time drinking at water stations scented with dingo odour. Our results provide support for the idea that dingo odour exerts a stronger interference effect on foxes than conspecific odour, but suggest that the odours of both larger dingoes and unfamiliar conspecifics curtailed foxes' acquisition of food resources. PMID:26296332

  10. [Odor perception in relation to age, general health, nutritional status, and dental status].

    PubMed

    Griep, M I; Mets, T F; Vogelaere, P; Collys, K; Laska, M; Massart, D L

    1997-02-01

    Many studies have shown that odour perception declines with age. Considering the possible role of age-related phenomena such as general health, dental health and nutrition in such a decline, their joint effect on variability in odour perception was evaluated in the present study. 73 apparently healthy adults aged from 53 to 86 years (median age = 66), living in the community, took part in this study. The SENIEUR protocol was used to assess the general health status and anthropometric measures were obtained to assess the nutritional status. The sensory detection threshold for isoamylacetate (banana odour) was determined as the lowest detectable odour concentration. Dental status was assessed by a questionnaire on the presence of natural teeth and wearing of dentures. Those in poor general health had significantly higher mean odour thresholds (2.35, SD = 1.34), where threshold concentration was expressed as -log(mol/l), than those in good (3.47, SD = 1.46) or reasonably general health (3.75, SD = 1.02). Partial denture wearers had significantly higher odour thresholds (2.99, SD = 1.12) than those having only natural teeth (4.24, SD = 1.43). Significant correlations between age and anthropometrical values were found, indicating that with age, muscle mass particularly in women decreases (r = -0.50). Odour perception of women correlated significantly inversely with triceps skinfold thickness (r = -0.42), indicating that poor sense of small is associated with high body content of fat. Our results indicate that general health and dental state are important age-associated factors in odour perception. Since age does not show a significant independent effect, neither in an analysis of variance, nor in a multiple regression analysis, such factors tend to become more important than chronological age per se.

  11. Seasonal control of odour preferences of meadow voles (Microtus pennsylvanicus) by photoperiod and ovarian hormones.

    PubMed

    Ferkin, M H; Zucker, I

    1991-07-01

    During the spring-summer breeding season, female meadow voles prefer odours of males over those of females, but in the autumn-winter season of reproductive quiescence this preference is reversed. Females housed in long (14 h light/day) and short (10 h light/day) photoperiods, respectively, had odour preferences comparable to those of spring and autumn voles, respectively. The preference of long-photoperiod voles for male over female odours was reversed by ovariectomy and restored by treatment with oestradiol. By contrast, neither ovariectomy nor oestradiol affected odour preferences of short-photoperiod voles. Long days appear to influence olfactory preferences by altering ovarian hormone secretion. The failure of oestradiol to affect odour preferences in short photoperiods suggests that the neural substrates mediating this behavioural response are refractory to oestrogens during the nonbreeding season. PMID:1886099

  12. Close encounters: contributions of carbon dioxide and human skin odour to finding and landing on a host in Aedes aegypti

    PubMed Central

    LACEY, EMERSON S.; RAY, ANANDASANKAR; CARDÉ, RING T.

    2014-01-01

    In a wind-tunnel study, the upwind flight and source location of female Aedes aegypti to plumes of carbon dioxide (CO2) gas and odour from human feet is tested. Both odour sources are presented singly and in combination. Flight upwind along the plumes is evident for both CO2 and odour from human feet when the odours are presented alone. Likewise, both odour sources are located by more than 70% of mosquitoes in less than 3 min. When both CO2 and odour from human feet are presented simultaneously in two different choice tests (with plumes superimposed or with plumes separated), there is no evidence that females orientate along the plume of CO2 and only a few mosquitoes locate its source. Rather, the foot odour plume is navigated and the source of foot odour is located by over 80% of female Ae. aegypti. When a female is presented a plume of CO2 within a broad plume of human foot odour of relatively low concentration, the source of CO2 is not located; instead, flight is upwind in the diffuse plume of foot odour. Although upwind flight by Ae. aegypti at long range is presumably induced by CO2 and the threshold of response to skin odours is lowered, our findings suggest that once females have arrived near a prospective human host, upwind orientation and landing are largely governed by the suite of odours from a human foot, while orientation is no longer influenced by CO2. PMID:24839345

  13. King penguins can detect two odours associated with conspecifics.

    PubMed

    Cunningham, Gregory B; Bonadonna, Francesco

    2015-11-01

    Recent studies on olfaction in penguins have focused on their use of odours while foraging. It has been proposed for some seabirds that an olfactory landscape shaped by odours coming from feeding areas exists. Islands and colonies, however, may also contribute to the olfactory landscape and may act as an orienting map. To test sensitivities to a colony scent we studied whether King penguins (Aptenodytes patagonicus) could detect the smell of sand, feathers or feces by holding presentations beneath their beaks while they naturally slept on the beach. Penguins had a significantly greater response to the feathers and feces presentations than to sand. Although only a first step in exploring a broader role of olfaction in this species, our results raise the possibility of olfaction being used by King penguins in three potential ways: (1) locating the colony from the water or the shore, (2) finding the rendezvous zone within the colony where a chick or partner may be found, or (3) recognizing individuals by scent, as in Humboldt penguins (Spheniscus demersus). PMID:26385329

  14. Sensor fusion III: 3-D perception and recognition; Proceedings of the Meeting, Boston, MA, Nov. 5-8, 1990

    NASA Technical Reports Server (NTRS)

    Schenker, Paul S. (Editor)

    1991-01-01

    The volume on data fusion from multiple sources discusses fusing multiple views, temporal analysis and 3D motion interpretation, sensor fusion and eye-to-hand coordination, and integration in human shape perception. Attention is given to surface reconstruction, statistical methods in sensor fusion, fusing sensor data with environmental knowledge, computational models for sensor fusion, and evaluation and selection of sensor fusion techniques. Topics addressed include the structure of a scene from two and three projections, optical flow techniques for moving target detection, tactical sensor-based exploration in a robotic environment, and the fusion of human and machine skills for remote robotic operations. Also discussed are K-nearest-neighbor concepts for sensor fusion, surface reconstruction with discontinuities, a sensor-knowledge-command fusion paradigm for man-machine systems, coordinating sensing and local navigation, and terrain map matching using multisensing techniques for applications to autonomous vehicle navigation.

  15. Diet and growth effects in panel assessment of sheepmeat odour and flavour.

    PubMed

    Rousset-Akrim, S; Young, O A; Berdagué, J L

    1997-02-01

    The effects of sheep age and diet on several odours and flavours are described. Ram lambs raised on ewe's milk then a corn-based diet were compared with lambs raised on milk and a pasture of grass/clover, six treatments in all. A seventh treatment comprised very old ewes maintained on pasture. Fat and lean from forequarters was minced and cooked together. Cooked lean was assessed for intensity by a sensory panel for 10 flavour attributes. Four showed significant (P < 0.01) treatment effects: 'sheepmeat', 'animal', 'liver', and 'poultry'. Sheepmeat flavour was highest in the slow-grown pasture-fed lambs. Animal flavour-the flavour associated with the odour of confined livestock-showed a similar pattern with treatment. Liver flavour was highest in ewe meat, and the biochemical origin of this flavour is discussed. Eleven related odour attributes were assessed on the rendered fat with a novel olfactometer. Five attributes showed highly significant treatment effects for intensity (P < 0.001): animal and sheepmeat odours showed a similar distribution to the equivalent flavours; likewise cabbage and rancid odours were associated with the two slow-grown pasture treatments. A comparison of the odour and flavour statistics showed that the sense of smell was the more discriminating in sheepmeat assessment, and also confirmed that fat was the true source of sheepmeat odour/flavour. In respect of sheepmeat production for effective marketing, the data showed that at 90 days, a pastoral diet resulted in slightly enhanced odours when compared with a corn-based diet. By 215 days, however, many undesirable odours were exacerbated. Since these older rams were more sexually developed, a sex rather than an age effect could not be excluded. Rendered fat from this work was further used in a companion study (Yang et al., 1997. Meat Sci., 45, 183-200) in an attempt to link individual volatile compounds to odour attributes. PMID:22061301

  16. Individual differences in language ability are related to variation in word recognition, not speech perception: Evidence from eye-movements

    PubMed Central

    McMurray, Bob; Munson, Cheyenne; Tomblin, J. Bruce

    2013-01-01

    Purpose This study examined speech perception deficits associated with individual differences in language ability contrasting auditory, phonological or lexical accounts by asking if lexical competition is differentially sensitive to fine-grained acoustic variation. Methods 74 adolescents with a range of language abilities (including 35 impaired) participated in an experiment based on McMurray, Tanenhaus and Aslin (2002). Participants heard tokens from six 9-step Voice Onset Time (VOT) continua spanning two words (beach/peach, beak/peak, etc), while viewing a screen containing pictures of those words and two unrelated objects. Participants selected the referent while eye-movements to each picture were monitored as a measure of lexical activation. Fixations were examined as a function of both VOT and language ability. Results Eye-movements were sensitive to within-category VOT differences: as VOT approached the boundary, listeners made more fixations to the competing word. This did not interact with language ability, suggesting that language impairment is not associated with differential auditory sensitivity or phonetic categorization. Listeners with poorer language skills showed heightened competitors fixations overall, suggesting a deficit in lexical processes. Conclusions Language impairment may be better characterized by a deficit in lexical competition (inability to suppress competing words), rather than differences phonological categorization or auditory abilities. PMID:24687026

  17. Variation in nestmate recognition ability among polymorphic leaf-cutting ant workers.

    PubMed

    Larsen, Janni; Fouks, Bertrand; Bos, Nick; d'Ettorre, Patrizia; Nehring, Volker

    2014-11-01

    A key feature for the success of social insects is division of labour, allowing colony members to specialize on different tasks. Nest defence is a defining task for social insects since it is crucial for colony integrity. A particularly impressive and well-known case of worker specialization in complex hymenopteran societies is found in leaf-cutting ants of the genera Atta and Acromyrmex. We hypothesized that three morphological worker castes of Acromyrmex echinatior differ in their likelihood to attack intruders, and show that major workers are more aggressive towards non-nestmate workers than medium and minor workers. Moreover, minors do not discriminate between nestmate and non-nestmate brood, while larger workers do. We further show that A. echinatior ants use cuticular chemical compounds for nestmate recognition. We took advantage of the natural variation in the cuticular compounds between colonies to investigate the proximate factors that may have led to the observed caste differences in aggression. We infer that major workers differ from medium workers in their general propensity to attack intruders (the "action component" of the nestmate recognition system), while minors seem to be less sensitive to foreign odours ("perception component"). Our results highlight the importance of proximate mechanisms underlying social insect behaviour, and encourage an appreciation of intra-colony variation when analysing colony-level traits such as nest defence. PMID:25205477

  18. Catalytic ozonation for odour removal of high temperature alumina refinery condensate.

    PubMed

    Wang, Xinguang; Guan, Jing; Stuetz, Richard M

    2012-01-01

    Odour emissions from aluminium processing can cause an impact on local communities surrounding such facilities. Of particular concern is fugitive odours emitted from the handling and use of refinery condensate streams, particularly the digestion condensate. This study evaluated the application of using catalytic ozonation to treat alumina refinery condensate in order to remove the potential emission of odourous compounds from the industrial wastewater. The technical challenges in treating the alumina refinery condensate are the high pH and temperatures of the wastewater effluent (over 80 °C and pH above 10) due the industrial process. The odour removal efficiencies for different catalysts (FeCl(3), MnO, and MnSO(4)) under experimental conditions in terms of controlled pH, temperature and ozone dosage were determined before and after ozone treatment using dynamic olfactometry. The result demonstrated that the addition of both FeCl(3) and MnO catalysts improved odour removal efficiencies during the ozonation of alumina condensates at similar pH and temperature conditions. FeCl(3) and MnO had similar enhancement for odour removal, however MnO was determined to be more appropriate than MnSO(4) for odour removal due to the colouration of the treated condensate.

  19. Evaluation of the odour reduction potential of alternative cover materials at a commercial landfill.

    PubMed

    Solan, P J; Dodd, V A; Curran, T P

    2010-02-01

    The availability of virgin soils and traditional landfill covers are not only costly and increasingly becoming scarce, but they also reduce the storage capacity of landfill. The problem can be overcome by the utilisation of certain suitable waste streams as alternative landfill covers. The objective of this study was to assess the suitability of Construction & Demolition fines (C&D), Commercial & Industrial fines (C&I) and woodchip (WC) as potential landfill cover materials in terms of odour control. Background odour analysis was conducted to determine if any residual odour was emitted from the cover types. It was deemed negligible for the three materials. The odour reduction performance of each of the materials was also examined on an area of an active landfill site. A range of intermediate cover compositions were also studied to assess their performance. Odour emissions were sampled using a Jiang hood and analysed. Results indicate that the 200 mm deep combination layer of C&D and wood chip used on-site is adequate for odour abatement. The application of daily cover was found to result in effective reduction allowing for the background odour of woodchip. PMID:19786346

  20. MHC-correlated odour preferences in humans and the use of oral contraceptives

    PubMed Central

    Roberts, S. Craig; Gosling, L. Morris; Carter, Vaughan; Petrie, Marion

    2008-01-01

    Previous studies in animals and humans show that genes in the major histocompatibility complex (MHC) influence individual odours and that females often prefer odour of MHC-dissimilar males, perhaps to increase offspring heterozygosity or reduce inbreeding. Women using oral hormonal contraceptives have been reported to have the opposite preference, raising the possibility that oral contraceptives alter female preference towards MHC similarity, with possible fertility costs. Here we test directly whether contraceptive pill use alters odour preferences using a longitudinal design in which women were tested before and after initiating pill use; a control group of non-users were tested with a comparable interval between test sessions. In contrast to some previous studies, there was no significant difference in ratings between odours of MHC-dissimilar and MHC-similar men among women during the follicular cycle phase. However, single women preferred odours of MHC-similar men, while women in relationships preferred odours of MHC-dissimilar men, a result consistent with studies in other species, suggesting that paired females may seek to improve offspring quality through extra-pair partnerships. Across tests, we found a significant preference shift towards MHC similarity associated with pill use, which was not evident in the control group. If odour plays a role in human mate choice, our results suggest that contraceptive pill use could disrupt disassortative mate preferences. PMID:18700206

  1. Monitoring of pile composting process of OFMSW at full scale and evaluation of odour emission impact.

    PubMed

    Gutiérrez, M C; Martín, M A; Serrano, A; Chica, A F

    2015-03-15

    In this study, the evolution of odour concentration (ouE/m(3)STP) emitted during the pile composting of the organic fraction of municipal solid waste (OFMSW) was monitored by dynamic olfactometry. Physical-chemical variables as well as the respirometric variables were also analysed. The aim of this work was twofold. The first was to determine the relationship between odour and traditional variables to determine if dynamic olfactometry is a feasible and adequate technique for monitoring an aerobic stabilisation process (composting). Second, the composting process odour impact on surrounding areas was simulated by a dispersion model. The results showed that the decrease of odour concentration, total organic carbon and respirometric variables was similar (around 96, 96 y 98% respectively). The highest odour emission (5224 ouE/m(3)) was reached in parallel with the highest microbiological activity (SOUR and OD20 values of 25 mgO2/gVS · h and 70 mgO2/gVS, respectively). The validity of monitoring odour emissions during composting in combination with traditional and respirometric variables was demonstrated by the adequate correlation obtained between the variables. Moreover, the quantification of odour emissions by dynamic olfactometry and the subsequent application of the dispersion model permitted making an initial prediction of the impact of odorous emissions on the population. Finally, the determination of CO2 and CH4 emissions allowed the influence of composting process on carbon reservoirs and global warming to be evaluated. PMID:25572673

  2. Preliminary observation on the effect of baking soda volume on controlling odour from discarded organic waste

    SciTech Connect

    Qamaruz-Zaman, N. Kun, Y.; Rosli, R.-N.

    2015-01-15

    Highlights: • Approximately 50 g baking soda reduced odour concentration by 70%. • Reducing volatile acid concentration reduces odour concentration. • Ammonia has less effect on odour concentration. - Abstract: Food wastes with high moisture and organic matter content are likely to emit odours as a result of the decomposition process. The management of odour from decomposing wastes is needed to sustain the interest of residents and local councils in the source separation of kitchen wastes. This study investigated the potential of baking soda (at 50 g, 75 g and 100 g per kg food waste) to control odour from seven days stored food waste. It was found that 50 g of baking soda, spread at the bottom of 8 l food wastes bin, can reduce the odour by about 70%. A higher amount (above 100 g) is not advised as a pH higher than 9.0 may be induced leading to the volatilization of odorous ammonia. This research finding is expected to benefit the waste management sector, food processing industries as well as the local authorities where malodour from waste storage is a pressing issue.

  3. Decomposition Odour Profiling in the Air and Soil Surrounding Vertebrate Carrion

    PubMed Central

    2014-01-01

    Chemical profiling of decomposition odour is conducted in the environmental sciences to detect malodourous target sources in air, water or soil. More recently decomposition odour profiling has been employed in the forensic sciences to generate a profile of the volatile organic compounds (VOCs) produced by decomposed remains. The chemical profile of decomposition odour is still being debated with variations in the VOC profile attributed to the sample collection technique, method of chemical analysis, and environment in which decomposition occurred. To date, little consideration has been given to the partitioning of odour between different matrices and the impact this has on developing an accurate VOC profile. The purpose of this research was to investigate the decomposition odour profile surrounding vertebrate carrion to determine how VOCs partition between soil and air. Four pig carcasses (Sus scrofa domesticus L.) were placed on a soil surface to decompose naturally and their odour profile monitored over a period of two months. Corresponding control sites were also monitored to determine the VOC profile of the surrounding environment. Samples were collected from the soil below and the air (headspace) above the decomposed remains using sorbent tubes and analysed using gas chromatography-mass spectrometry. A total of 249 compounds were identified but only 58 compounds were common to both air and soil samples. This study has demonstrated that soil and air samples produce distinct subsets of VOCs that contribute to the overall decomposition odour. Sample collection from only one matrix will reduce the likelihood of detecting the complete spectrum of VOCs, which further confounds the issue of determining a complete and accurate decomposition odour profile. Confirmation of this profile will enhance the performance of cadaver-detection dogs that are tasked with detecting decomposition odour in both soil and air to locate victim remains. PMID:24740412

  4. Decomposition odour profiling in the air and soil surrounding vertebrate carrion.

    PubMed

    Forbes, Shari L; Perrault, Katelynn A

    2014-01-01

    Chemical profiling of decomposition odour is conducted in the environmental sciences to detect malodourous target sources in air, water or soil. More recently decomposition odour profiling has been employed in the forensic sciences to generate a profile of the volatile organic compounds (VOCs) produced by decomposed remains. The chemical profile of decomposition odour is still being debated with variations in the VOC profile attributed to the sample collection technique, method of chemical analysis, and environment in which decomposition occurred. To date, little consideration has been given to the partitioning of odour between different matrices and the impact this has on developing an accurate VOC profile. The purpose of this research was to investigate the decomposition odour profile surrounding vertebrate carrion to determine how VOCs partition between soil and air. Four pig carcasses (Sus scrofa domesticus L.) were placed on a soil surface to decompose naturally and their odour profile monitored over a period of two months. Corresponding control sites were also monitored to determine the VOC profile of the surrounding environment. Samples were collected from the soil below and the air (headspace) above the decomposed remains using sorbent tubes and analysed using gas chromatography-mass spectrometry. A total of 249 compounds were identified but only 58 compounds were common to both air and soil samples. This study has demonstrated that soil and air samples produce distinct subsets of VOCs that contribute to the overall decomposition odour. Sample collection from only one matrix will reduce the likelihood of detecting the complete spectrum of VOCs, which further confounds the issue of determining a complete and accurate decomposition odour profile. Confirmation of this profile will enhance the performance of cadaver-detection dogs that are tasked with detecting decomposition odour in both soil and air to locate victim remains.

  5. The analgesic effect of odour and music upon dressing change.

    PubMed

    Kane, F M A; Brodie, E E; Coull, A; Coyne, L; Howd, A; Milne, A; Niven, C C; Robbins, R

    Vascular wounds may require frequent dressing changes over a long period of time, often involving pain, which may not be adequately controlled with conventional analgesia. Complementary analgesia may be beneficial as an adjunctive therapy. This pilot study presented eight patients with two odour therapies, lavender and lemon, two music therapies, relaxing and preferred music and a control condition, during vascular wound dressing changes. Although the therapies did not reduce the pain intensity during the dressing change there was a significant reduction in pain intensity for the lavender therapy and a reduction in pain intensity for the relaxing music therapy after the dressing change. This supports the use of these complementary therapies, which are inexpensive, easy to administer and have no known side effects, as adjunctive analgesia in this patient population. Earlier administration before dressing change may enhance these effects. Further research is required to ascertain why certain complementary therapies are more effective than others at relieving pain.

  6. Taste and odour issues in South Korea's drinking water industry.

    PubMed

    Bae, B U; Shin, H S; Choi, J J

    2007-01-01

    This paper reviews taste and odour (T&O) issues of South Korea's water industry. For this purpose, an overview of the water supply systems and drinking water standards is presented and some results from citizen surveys for customer satisfaction are included. A case study is presented in which the water intake was shifted from inside a main reservoir to a downstream location due to T&O problems. It is true that the South Korean water industry has long relied on the tolerance of consumers for periodic T&O events. Recently the South Korean water industry has become aware that the T&O problems are at the centre of consumers' concerns and has taken several positive approaches. These include monitoring T&O events using sensory and instrumental methods, installation of a baffled-channel PAC contactor and application of advanced water treatment processes.

  7. Observations on the effects of odours on the homeopathic response.

    PubMed

    McGuigan, Moira

    2014-07-01

    Samuel Hahnemann described incidences where the homeopathic response was disrupted by noxious smells in the environment. An earlier paper proposed that homeopathic medicines may be sensed by vomeronasal cells (VNCs) i.e. microvillus or brush cells in the vomeronasal organ (VNO), the taste buds and associated with the trigeminal nerve and nervus terminalis. This paper proposes an extension to the theory and suggests that a subset of solitary chemosensory cells (SCCs) in the diffuse chemosensory system (DCS) that is morphologically similar to VNCs might also be receptive to homeopathic medicines. The types of odours that may interfere with this process are described. Two clinical cases of disruption of the homeopathic response are given as examples, showing that successful re-establishment of remedy action can be produced by timely repetition of the medicine. The ramifications on clinical homeopathic practice are discussed.

  8. Predator odour and its impact on male fertility and reproduction in Phodopus campbelli hamsters

    NASA Astrophysics Data System (ADS)

    Vasilieva, N. Y.; Cherepanova, E. V.; von Holst, D.; Apfelbach, R.

    This study investigated the influence of cat urine odour in suppressing development and fertility in Campbell's hamster males. Exposure to this odour from postnatal day 11 until day 45 (sexual maturation) resulted in reduced sex organ weights, reduced testosterone levels and in an increase in abnormalities of the synaptonemal complex in both sex chromosomes and autosomes. Subsequent breeding experiments revealed a significant decrease in litter size. All these data indicate a severe effect of predator odour on the breeding success of potential prey species. It is assumed that these effects are caused by the sulphurous compounds in the urine; however, the underlying mechanisms are not yet known.

  9. Odour Mapping Under Strong Backgrounds With a Metal Oxide Sensor Array

    NASA Astrophysics Data System (ADS)

    Ziyatdinov, Andrey; Calvo, José María Blanco; Lechón, Miguel; Bermúdez i Badia, Sergi; Verschure, Paul F. M. J.; Marco, Santiago; Perera, Alexandre

    2011-09-01

    This work describes the data from navigation experiments with the mobile robot, equipped with the sensor array of three MOX gas sensors. Performed four series of measurements aim to explore the capabilities of sensor array to build the odour map with one or two odour sources in the wind tunnel space. It was demonstrated that the method based on Independent Component Analysis (ICA) is able to discriminate two odour sources, that in future can be used in the surge-and-cast robot navigation algorithm.

  10. Colorectal cancer screening with odour material by canine scent detection

    PubMed Central

    Kohnoe, Shunji; Yamazato, Tetsuro; Satoh, Yuji; Morizono, Gouki; Shikata, Kentaro; Morita, Makoto; Watanabe, Akihiro; Morita, Masaru; Kakeji, Yoshihiro; Inoue, Fumio; Maehara, Yoshihiko

    2011-01-01

    Objective Early detection and early treatment are of vital importance to the successful treatment of various cancers. The development of a novel screening method that is as economical and non-invasive as the faecal occult blood test (FOBT) for early detection of colorectal cancer (CRC) is needed. A study was undertaken using canine scent detection to determine whether odour material can become an effective tool in CRC screening. Design Exhaled breath and watery stool samples were obtained from patients with CRC and from healthy controls prior to colonoscopy. Each test group consisted of one sample from a patient with CRC and four control samples from volunteers without cancer. These five samples were randomly and separately placed into five boxes. A Labrador retriever specially trained in scent detection of cancer and a handler cooperated in the tests. The dog first smelled a standard breath sample from a patient with CRC, then smelled each sample station and sat down in front of the station in which a cancer scent was detected. Results 33 and 37 groups of breath and watery stool samples, respectively, were tested. Among patients with CRC and controls, the sensitivity of canine scent detection of breath samples compared with conventional diagnosis by colonoscopy was 0.91 and the specificity was 0.99. The sensitivity of canine scent detection of stool samples was 0.97 and the specificity was 0.99. The accuracy of canine scent detection was high even for early cancer. Canine scent detection was not confounded by current smoking, benign colorectal disease or inflammatory disease. Conclusions This study shows that a specific cancer scent does indeed exist and that cancer-specific chemical compounds may be circulating throughout the body. These odour materials may become effective tools in CRC screening. In the future, studies designed to identify cancer-specific volatile organic compounds will be important for the development of new methods for early detection of CRC

  11. Culicoides midge trap enhancement with animal odour baits in Scotland.

    PubMed

    Mands, V; Kline, D L; Blackwell, A

    2004-12-01

    Examples of the commercial trap Mosquito Magnet Pro (MMP emitting attractant 1-octen-3-ol in carbon dioxide 500 mL/min generated from propane fuel), were run 24 h/day on the Isle of Skye, Scotland, during June-August 2001 and evaluated for catching Culicoides biting midges (Diptera: Ceratopogonidae). From 30 days trapping, the catch averaged 2626 +/- 1358 Culicoides females/trap/day (mean +/- SE, range 558 +/- 139 to 6088 +/- 3597, for five sets of six consecutive nights), predominantly the pest Culicoides impunctatus Goetghebuer (68% overall), plus C. vexans (Staeger) > C. delta Edwards > C. pulicaris (L.) > C. lupicaris Downs & Kettle > C. albicans (Winnertz) > other Culicoides spp. Attempts were made to enhance the odour baiting system by adding hexane-extracts (2.1 mg/day) of hair samples from large host animals, resulting in the following effects on Culicoides collections: sheep - 53 %, red deer - 26 %, calf + 20%, pony + 40%, water buffalo + 262%, with greatest increases for C. impunctatus and C. pulicaris. Serial concentrations of these animal extracts (10(-1) - 10(-3) x 2.2 g/mL) were assayed on parous female C. impunctatus response in a Y-tube olfactometer (air-flow 150 mL/min), and by electroantennogram (EAG) on Culicoides nubeculosus Meigen laboratory-reared parous females. Positive behavioural responses to host odours were dose-dependent: the water buffalo extract being most active (threshold 0.22 g/mL), similar to deer, whereas other host extracts were > or = 10-fold less active. Correspondingly, the EAG threshold was lowest for water buffalo, 10-fold greater for deer, calf and pony, but not detected for sheep. If the active component(s) of these host extracts can be identified and synthesized, they might be employed to improve the capture of Culicoides midges for local control by removal trapping.

  12. Kin Recognition in Bacteria.

    PubMed

    Wall, Daniel

    2016-09-01

    The ability of bacteria to recognize kin provides a means to form social groups. In turn these groups can lead to cooperative behaviors that surpass the ability of the individual. Kin recognition involves specific biochemical interactions between a receptor(s) and an identification molecule(s). Recognition specificity, ensuring that nonkin are excluded and kin are included, is critical and depends on the number of loci and polymorphisms involved. After recognition and biochemical perception, the common ensuing cooperative behaviors include biofilm formation, quorum responses, development, and swarming motility. Although kin recognition is a fundamental mechanism through which cells might interact, microbiologists are only beginning to explore the topic. This review considers both molecular and theoretical aspects of bacterial kin recognition. Consideration is also given to bacterial diversity, genetic relatedness, kin selection theory, and mechanisms of recognition. PMID:27359217

  13. Do you smell what I smell? Genetic variation in olfactory perception.

    PubMed

    Logan, Darren W

    2014-08-01

    The sense of smell is mediated by the detection of chemical odours by ORs (olfactory receptors) in the nose. This initiates a neural percept of the odour in the brain, which may provoke an emotional or behavioural response. Analogous to colour-blindness in the visual system, some individuals report a very different percept of specific odours to others, in terms of intensity, valence or detection threshold. A significant proportion of variance in odour perception is heritable, and recent advances in genome sequencing and genotyping technologies have permitted studies into the genes that underpin these phenotypic differences. In the present article, I review the evidence that OR genes are extremely variable between individuals. I argue that this contributes to a unique receptor repertoire in our noses that provides us each with a personalized perception of our environment. I highlight specific examples where known OR variants influence odour detection and discuss the wider implications of this for both humans and other mammals that use chemical communication for social interaction. PMID:25109969

  14. Do you smell what I smell? Genetic variation in olfactory perception.

    PubMed

    Logan, Darren W

    2014-08-01

    The sense of smell is mediated by the detection of chemical odours by ORs (olfactory receptors) in the nose. This initiates a neural percept of the odour in the brain, which may provoke an emotional or behavioural response. Analogous to colour-blindness in the visual system, some individuals report a very different percept of specific odours to others, in terms of intensity, valence or detection threshold. A significant proportion of variance in odour perception is heritable, and recent advances in genome sequencing and genotyping technologies have permitted studies into the genes that underpin these phenotypic differences. In the present article, I review the evidence that OR genes are extremely variable between individuals. I argue that this contributes to a unique receptor repertoire in our noses that provides us each with a personalized perception of our environment. I highlight specific examples where known OR variants influence odour detection and discuss the wider implications of this for both humans and other mammals that use chemical communication for social interaction.

  15. An inkjet-printed bioactive paper sensor that reports ATP through odour generation.

    PubMed

    Zhang, Zhuyuan; Wang, Jingyun; Ng, Robin; Li, Yingfu; Wu, Zaisheng; Leung, Vincent; Imbrogno, Spencer; Pelton, Robert; Brennan, John D; Filipe, Carlos D M

    2014-10-01

    We describe an inkjet printed paper-based sensor that reports ATP by the enzyme catalysed hydrolysis of S-methyl-L-cysteine generating an odour (methyl mercaptan) that is easily detectable by the human nose.

  16. Preliminary observation on the effect of baking soda volume on controlling odour from discarded organic waste.

    PubMed

    Qamaruz-Zaman, N; Kun, Y; Rosli, R-N

    2015-01-01

    Food wastes with high moisture and organic matter content are likely to emit odours as a result of the decomposition process. The management of odour from decomposing wastes is needed to sustain the interest of residents and local councils in the source separation of kitchen wastes. This study investigated the potential of baking soda (at 50 g, 75 g and 100g per kg food waste) to control odour from seven days stored food waste. It was found that 50 g of baking soda, spread at the bottom of 8l food wastes bin, can reduce the odour by about 70%. A higher amount (above 100g) is not advised as a pH higher than 9.0 may be induced leading to the volatilization of odorous ammonia. This research finding is expected to benefit the waste management sector, food processing industries as well as the local authorities where malodour from waste storage is a pressing issue.

  17. Preliminary observation on the effect of baking soda volume on controlling odour from discarded organic waste.

    PubMed

    Qamaruz-Zaman, N; Kun, Y; Rosli, R-N

    2015-01-01

    Food wastes with high moisture and organic matter content are likely to emit odours as a result of the decomposition process. The management of odour from decomposing wastes is needed to sustain the interest of residents and local councils in the source separation of kitchen wastes. This study investigated the potential of baking soda (at 50 g, 75 g and 100g per kg food waste) to control odour from seven days stored food waste. It was found that 50 g of baking soda, spread at the bottom of 8l food wastes bin, can reduce the odour by about 70%. A higher amount (above 100g) is not advised as a pH higher than 9.0 may be induced leading to the volatilization of odorous ammonia. This research finding is expected to benefit the waste management sector, food processing industries as well as the local authorities where malodour from waste storage is a pressing issue. PMID:25445259

  18. A pilot-scale study on biofilters for controlling animal rendering process odours.

    PubMed

    Luo, J

    2001-01-01

    Heating of animal tissue during the process of rendering liberates a variety of odorous compounds. The performance of biofiltration in removing these odours was investigated using pilot-scale biofilters containing different media (sand, finely and coarsely crushed wood bark, and bark/soil mixture). Odour-removal performance of the biofilters was determined using olfactometry. Biofilter odour removal efficiencies of between 29.7% and 99.9% were measured at influent odour concentrations of between 143,100 and 890,000 odour units m(-3), and various air loading rates (0.074-0.592 m(-3) air m(-3) medium min(-1)). Biofilters with bark or bark/soil media and low air loading rates gave the best odour removal. The bark and sand biofilters generally maintained good odour reduction for about three years at an air loading rate of 0.148 m(-3) air m(-3) medium min(-1). Drainage from the biofilters contained significant concentrations of nitrogenous and organic compounds, suggesting that controlled leaching has the potential to remove accumulated substances in biofilter media from rendering gas emissions and increase the longevity of a biofilter system. High pressure drop across biofilter media can adversely affect the odour removal performance. Sand and fine bark, due to their small particle size, caused high pressure drops. Coarse bark showed negligible pressure drop at several examined air loading rates. Pressure drop also increased with moisture content, particularly in sand and fine bark biofilters. Overall pressure drop characteristics of the biofilters described in this paper were maintained without significant change over the three year operation.

  19. The effect of complete versus incomplete information on odour discrimination in a parasitic wasp.

    PubMed

    Vet; De jong AG; Franchi; Papaj

    1998-05-01

    We studied the function of learning in the parasitoid Leptopilina heterotoma by looking at discrimination of odour stimuli used in foraging for a host. To optimize the rate of encounters with hosts, these parasitoids are expected to assess the extent to which variation in host-substrate odours is reliably associated with variation in the presence of hosts, that is, substrate profitability. Where the association is reliable, parasitoids should attend to variation in odours and discriminate between them; where it is not, they should ignore it. We hypothesized that foraging decisions are based on the completeness of information the animal has about differences in substrate profitabilities. Our laboratory studies showed that discrimination and non-discrimination of odour stimuli are dynamic behavioural decisions that can be related to the degree of substrate variation and to an animal's informational state. In wind-tunnel studies, females learned to discriminate between odours from substrates that were qualitatively different, for example, between odours from apple and pear substrates or between yeast substrates with different C6 compounds added. They did not discriminate when differences were small (e.g. between odours from two apple varieties or between yeast patches with different concentrations of ethyl acetate), unless unrewarding experiences provided evidence of the absence of hosts in one of the substrates. Hence, we suggest that non-discrimination between odour stimuli in L. heterotoma is not a lack of ability to discriminate but a functional decision by the parasitoid. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour. PMID:9632510

  20. Instrumental characterization of odour: a combination of olfactory and analytical methods.

    PubMed

    Zarra, T; Naddeo, V; Belgiorno, V; Reiser, M; Kranert, M

    2009-01-01

    Odour emissions are a major environmental issue in wastewater treatment plants and are considered to be the main cause of disturbance noticed by the exposed population. Odour measurement is carried out using analytical or sensorial methods. Sensorial analysis, being assigned to the "human sensor", is the cause of a considerable uncertainty. In this study a correlation between analytical and sensorial methods was investigated. A novel tool was used to both define odour indexes and characterise the odour sources and the volatile substances that cause annoyance in a wastewater treatment plant, with the aim to remove the subjective component in the measure of the odours and define the induced impact. The sources and the main chemical substances responsible for the olfactory annoyances were identified. Around 36 different substances were detected, with more than half being smell relevant components as well as responsible. Dimethyl disulphide was identified as key compound. Results highlight the applicability of highly correlation between analytical and sensorial methods in odour emission monitoring.

  1. Olfactory experience shapes the evaluation of odour similarity in ants: a behavioural and computational analysis

    PubMed Central

    Perez, Margot; Nowotny, Thomas; d'Ettorre, Patrizia

    2016-01-01

    Perceptual similarity between stimuli is often assessed via generalization, the response to stimuli that are similar to the one which was previously conditioned. Although conditioning procedures are variable, studies on how this variation may affect perceptual similarity remain scarce. Here, we use a combination of behavioural and computational analyses to investigate the influence of olfactory conditioning procedures on odour generalization in ants. Insects were trained following either absolute conditioning, in which a single odour (an aldehyde) was rewarded with sucrose, or differential conditioning, in which one odour (the same aldehyde) was similarly rewarded and another odour (an aldehyde differing in carbon-chain length) was punished with quinine. The response to the trained odours and generalization to other aldehydes were assessed. We show that olfactory similarity, rather than being immutable, varies with the conditioning procedure. Compared with absolute conditioning, differential conditioning enhances olfactory discrimination. This improvement is best described by a multiplicative interaction between two independent processes, the excitatory and inhibitory generalization gradients induced by the rewarded and the punished odour, respectively. We show that olfactory similarity is dramatically shaped by an individual's perceptual experience and suggest a new hypothesis for the nature of stimulus interactions underlying experience-dependent changes in perceptual similarity. PMID:27581883

  2. The nature and origin of cross-modal associations to odours.

    PubMed

    Stevenson, Richard J; Rich, Anina; Russell, Alex

    2012-01-01

    Several studies have demonstrated reliable cross-modal associations between odours and various visual, auditory, taste, and somatosensory attributes. How these associations arise is not well understood. We examined whether cross-modal associations to odours themselves form distinct groups, and whether these groupings relate to semantic (nameability, familiarity) and perceptual (intensity, irritancy, and hedonics) olfactory attributes. Participants evaluated 20 odours, varying in all of the latter attributes, and reported their visual, auditory, gustatory, and somatosensory associations for each. Significant inter-rater agreement was observed for all modalities except audition, and responses in all modalities were consistent with those obtained on a repeat test session 2 weeks later. Two groups of cross-modal odour associates emerged: one of which was related to the semantic attributes of odours and another which related to their perceptual attributes. The exception was taste, which was significantly associated with both. While these results suggest that both semantic and perceptual mechanisms underpin odour cross-modal matches, the data also point to the importance of hedonics as a further contributing mechanism.

  3. What Makes Us Smell: The Biochemistry of Body Odour and the Design of New Deodorant Ingredients.

    PubMed

    Natsch, Andreas

    2015-01-01

    Today, axilla odours are socially stigmatized and are targeted with deodorants and antiperspirants representing a multi-billion market. Axilla odours aren't simple byproducts of our metabolism but specifically formed by an intricate interplay between i) specific glands, ii) secreted amino acid conjugates of highly specific odorants and iii) selective enzymes present in microorganisms colonizing our skin, providing a natural 'controlled-release' mechanism. Within a multidisciplinary research project, we were able to elucidate the structure of key body odorants, isolate and characterize secreted amino acid conjugates and identify the enzymes responsible for odour release. These enzymes then served as targets for the development of specific active compounds in an almost medicinal chemistry approach, an approach rarely used in the cosmetic field so far. Here we review the key new insights into the biochemistry of human body odour formation, with some remarks on the experimental steps undertaken and hurdles encountered. The development of deodorant actives and the difficult path to market for such specifically acting cosmetic actives is discussed. The basic insights into the biochemistry also opened the way to address some questions in population genetics: Why have large proportions of Asians lost the 'ability' to form body odours? Do twins smell the same? Are our typical body odours indeed influenced by the immune system as often claimed? After addressing these questions, I'll conclude with the key remaining challenges in this field on an ecological niche that is 'anatomically very close to our heart'. PMID:26507593

  4. Olfactory experience shapes the evaluation of odour similarity in ants: a behavioural and computational analysis.

    PubMed

    Perez, Margot; Nowotny, Thomas; d'Ettorre, Patrizia; Giurfa, Martin

    2016-08-31

    Perceptual similarity between stimuli is often assessed via generalization, the response to stimuli that are similar to the one which was previously conditioned. Although conditioning procedures are variable, studies on how this variation may affect perceptual similarity remain scarce. Here, we use a combination of behavioural and computational analyses to investigate the influence of olfactory conditioning procedures on odour generalization in ants. Insects were trained following either absolute conditioning, in which a single odour (an aldehyde) was rewarded with sucrose, or differential conditioning, in which one odour (the same aldehyde) was similarly rewarded and another odour (an aldehyde differing in carbon-chain length) was punished with quinine. The response to the trained odours and generalization to other aldehydes were assessed. We show that olfactory similarity, rather than being immutable, varies with the conditioning procedure. Compared with absolute conditioning, differential conditioning enhances olfactory discrimination. This improvement is best described by a multiplicative interaction between two independent processes, the excitatory and inhibitory generalization gradients induced by the rewarded and the punished odour, respectively. We show that olfactory similarity is dramatically shaped by an individual's perceptual experience and suggest a new hypothesis for the nature of stimulus interactions underlying experience-dependent changes in perceptual similarity. PMID:27581883

  5. Computer image processing and recognition

    NASA Technical Reports Server (NTRS)

    Hall, E. L.

    1979-01-01

    A systematic introduction to the concepts and techniques of computer image processing and recognition is presented. Consideration is given to such topics as image formation and perception; computer representation of images; image enhancement and restoration; reconstruction from projections; digital television, encoding, and data compression; scene understanding; scene matching and recognition; and processing techniques for linear systems.

  6. Distributed nestmate recognition in ants

    PubMed Central

    Esponda, Fernando; Gordon, Deborah M.

    2015-01-01

    We propose a distributed model of nestmate recognition, analogous to the one used by the vertebrate immune system, in which colony response results from the diverse reactions of many ants. The model describes how individual behaviour produces colony response to non-nestmates. No single ant knows the odour identity of the colony. Instead, colony identity is defined collectively by all the ants in the colony. Each ant responds to the odour of other ants by reference to its own unique decision boundary, which is a result of its experience of encounters with other ants. Each ant thus recognizes a particular set of chemical profiles as being those of non-nestmates. This model predicts, as experimental results have shown, that the outcome of behavioural assays is likely to be variable, that it depends on the number of ants tested, that response to non-nestmates changes over time and that it changes in response to the experience of individual ants. A distributed system allows a colony to identify non-nestmates without requiring that all individuals have the same complete information and helps to facilitate the tracking of changes in cuticular hydrocarbon profiles, because only a subset of ants must respond to provide an adequate response. PMID:25833853

  7. Distributed nestmate recognition in ants.

    PubMed

    Esponda, Fernando; Gordon, Deborah M

    2015-05-01

    We propose a distributed model of nestmate recognition, analogous to the one used by the vertebrate immune system, in which colony response results from the diverse reactions of many ants. The model describes how individual behaviour produces colony response to non-nestmates. No single ant knows the odour identity of the colony. Instead, colony identity is defined collectively by all the ants in the colony. Each ant responds to the odour of other ants by reference to its own unique decision boundary, which is a result of its experience of encounters with other ants. Each ant thus recognizes a particular set of chemical profiles as being those of non-nestmates. This model predicts, as experimental results have shown, that the outcome of behavioural assays is likely to be variable, that it depends on the number of ants tested, that response to non-nestmates changes over time and that it changes in response to the experience of individual ants. A distributed system allows a colony to identify non-nestmates without requiring that all individuals have the same complete information and helps to facilitate the tracking of changes in cuticular hydrocarbon profiles, because only a subset of ants must respond to provide an adequate response.

  8. Odour-evoked responses to queen pheromone components and to plant odours using optical imaging in the antennal lobe of the honey bee drone Apis mellifera L.

    PubMed

    Sandoz, Jean-Christophe

    2006-09-01

    The primordial functional role of honey bee males (drones) is to mate with virgin queens, a behaviour relying heavily on the olfactory detection of queen pheromone. In the present work I studied olfactory processing in the drone antennal lobe (AL), the primary olfactory centre of the insect brain. In drones, the AL consists of about 103 ordinary glomeruli and four enlarged glomeruli, the macroglomeruli (MG). Two macroglomeruli (MG1 and MG2) and approximately 20 ordinary glomeruli occupy the anterior surface of the antennal lobe and are thus accessible to optical recordings. Calcium imaging was used to measure odour-evoked responses to queen pheromonal components and plant odours. MG2 responded specifically to the main component of the queen mandibular pheromone, 9-ODA. The secondary components HOB and HVA each triggered activity in one, but not the same, ordinary glomerulus. MG1 did not respond to any of the tested stimuli. Plant odours induced signals only in ordinary glomeruli in a combinatorial manner, as in workers. This study thus shows that the major queen pheromonal component is processed in the most voluminous macroglomerulus of the drone antennal lobe, and that plant odours, as well as some queen pheromonal components, are processed in ordinary glomeruli.

  9. Odour-evoked responses to queen pheromone components and to plant odours using optical imaging in the antennal lobe of the honey bee drone Apis mellifera L.

    PubMed

    Sandoz, Jean-Christophe

    2006-09-01

    The primordial functional role of honey bee males (drones) is to mate with virgin queens, a behaviour relying heavily on the olfactory detection of queen pheromone. In the present work I studied olfactory processing in the drone antennal lobe (AL), the primary olfactory centre of the insect brain. In drones, the AL consists of about 103 ordinary glomeruli and four enlarged glomeruli, the macroglomeruli (MG). Two macroglomeruli (MG1 and MG2) and approximately 20 ordinary glomeruli occupy the anterior surface of the antennal lobe and are thus accessible to optical recordings. Calcium imaging was used to measure odour-evoked responses to queen pheromonal components and plant odours. MG2 responded specifically to the main component of the queen mandibular pheromone, 9-ODA. The secondary components HOB and HVA each triggered activity in one, but not the same, ordinary glomerulus. MG1 did not respond to any of the tested stimuli. Plant odours induced signals only in ordinary glomeruli in a combinatorial manner, as in workers. This study thus shows that the major queen pheromonal component is processed in the most voluminous macroglomerulus of the drone antennal lobe, and that plant odours, as well as some queen pheromonal components, are processed in ordinary glomeruli. PMID:16943499

  10. [Facial recognition and autism].

    PubMed

    Assumpçäo Júnior, F B; Sprovieri, M H; Kuczynski, E; Farinha, V

    1999-12-01

    Through the presentation of four facial expressions' illustrations, we evaluate the capacity of autistic children recognition, comparing with normal intelligence children and adults. The comparison of results was accomplished through the qui-square test. The differences observed were significant, showing that a disturbance of the facial expressions' perception is present in autistic children, and that it interferes directly in the social relationships.

  11. Habitats as complex odour environments: how does plant diversity affect herbivore and parasitoid orientation?

    PubMed

    Wäschke, Nicole; Hardge, Kristin; Hancock, Christine; Hilker, Monika; Obermaier, Elisabeth; Meiners, Torsten

    2014-01-01

    Plant diversity is known to affect success of host location by pest insects, but its effect on olfactory orientation of non-pest insect species has hardly been addressed. First, we tested in laboratory experiments the hypothesis that non-host plants, which increase odour complexity in habitats, affect the host location ability of herbivores and parasitoids. Furthermore, we recorded field data of plant diversity in addition to herbivore and parasitoid abundance at 77 grassland sites in three different regions in Germany in order to elucidate whether our laboratory results reflect the field situation. As a model system we used the herb Plantago lanceolata, the herbivorous weevil Mecinus pascuorum, and its larval parasitoid Mesopolobus incultus. The laboratory bioassays revealed that both the herbivorous weevil and its larval parasitoid can locate their host plant and host via olfactory cues even in the presence of non-host odour. In a newly established two-circle olfactometer, the weeviĺs capability to detect host plant odour was not affected by odours from non-host plants. However, addition of non-host plant odours to host plant odour enhanced the weeviĺs foraging activity. The parasitoid was attracted by a combination of host plant and host volatiles in both the absence and presence of non-host plant volatiles in a Y-tube olfactometer. In dual choice tests the parasitoid preferred the blend of host plant and host volatiles over its combination with non-host plant volatiles. In the field, no indication was found that high plant diversity disturbs host (plant) location by the weevil and its parasitoid. In contrast, plant diversity was positively correlated with weevil abundance, whereas parasitoid abundance was independent of plant diversity. Therefore, we conclude that weevils and parasitoids showed the sensory capacity to successfully cope with complex vegetation odours when searching for hosts. PMID:24416354

  12. Habitats as Complex Odour Environments: How Does Plant Diversity Affect Herbivore and Parasitoid Orientation?

    PubMed Central

    Wäschke, Nicole; Hardge, Kristin; Hancock, Christine; Hilker, Monika; Obermaier, Elisabeth; Meiners, Torsten

    2014-01-01

    Plant diversity is known to affect success of host location by pest insects, but its effect on olfactory orientation of non-pest insect species has hardly been addressed. First, we tested in laboratory experiments the hypothesis that non-host plants, which increase odour complexity in habitats, affect the host location ability of herbivores and parasitoids. Furthermore, we recorded field data of plant diversity in addition to herbivore and parasitoid abundance at 77 grassland sites in three different regions in Germany in order to elucidate whether our laboratory results reflect the field situation. As a model system we used the herb Plantago lanceolata, the herbivorous weevil Mecinus pascuorum, and its larval parasitoid Mesopolobus incultus. The laboratory bioassays revealed that both the herbivorous weevil and its larval parasitoid can locate their host plant and host via olfactory cues even in the presence of non-host odour. In a newly established two-circle olfactometer, the weeviĺs capability to detect host plant odour was not affected by odours from non-host plants. However, addition of non-host plant odours to host plant odour enhanced the weeviĺs foraging activity. The parasitoid was attracted by a combination of host plant and host volatiles in both the absence and presence of non-host plant volatiles in a Y-tube olfactometer. In dual choice tests the parasitoid preferred the blend of host plant and host volatiles over its combination with non-host plant volatiles. In the field, no indication was found that high plant diversity disturbs host (plant) location by the weevil and its parasitoid. In contrast, plant diversity was positively correlated with weevil abundance, whereas parasitoid abundance was independent of plant diversity. Therefore, we conclude that weevils and parasitoids showed the sensory capacity to successfully cope with complex vegetation odours when searching for hosts. PMID:24416354

  13. Odour removal with a trickling filter at a small WWTP strongly influenced by the tourism season.

    PubMed

    Patria, L; Cathelain, M; Laurens, P; Barbere, J P

    2001-01-01

    Etaples-Le Touquet's wastewater treatment plant (WWTP) is based on a coastal area of the Artois-Picardie region. The pollution load can vary from 20,000 p.e. to 60,000 p.e. over a weekend or in summer. The Collectivity and the Water Agency decided to cover and ventilate the main odour source points of the plant. The foul air was directed to a 2,500 m3/h inorganic bed biofilter (Alizair) for odour control. An odour monitoring took place during the first year of operation taking into account cold and warm seasons, high and low tourism seasons. The Alizair biofilter appeared an appropriate odour control process for small sized wastewater treatment plants, easy to operate and efficient even in areas where tourism seasons have a great impact on the pollution load arriving at the plant. The neighbourhood did not complain about odours any more and the operator was very confident with such a simple and effective system. The local Authorities and the Water Agency agreed to recommend Alizair biofilters with an autotrophic biomass adapted in the case of an old WWTP that cannot be up graded any more or for large pumping stations and wastewater storage prior treatment.

  14. Odour coding is bilaterally symmetrical in the antennal lobes of honeybees (Apis mellifera).

    PubMed

    Galizia, C G; Nägler, K; Hölldobler, B; Menzel, R

    1998-09-01

    The primary olfactory neuropil, the antennal lobe (AL) in insects, is organized in glomeruli. Glomerular activity patterns are believed to represent the across-fibre pattern of the olfactory code. These patterns depend on an organized innervation from the afferent receptor cells, and interconnections of local interneurons. It is unclear how the complex organization of the AL is achieved ontogenetically. In this study, we measured the functional activity patterns elicited by stimulation with odours in the right and the left AL of the same honeybee (Apis mellifera) using optical imaging of the calcium-sensitive dye calcium green. We show here that these patterns are bilaterally symmetrical (n=25 bees). This symmetry holds true for all odours tested, irrespective of their role as pheromones or as environmental odours, or whether they were pure substances or complex blends (n=13 odours). Therefore, we exclude that activity dependent mechanisms local to one AL determine the functional glomerular activity. This identity is genetically predetermined. Alternatively, if activity dependent processes are involved, bilateral connections would have to shape symmetry, or, temporal constraints could lead to identical patterns on both sides due to their common history of odour exposure. PMID:9758166

  15. Identification of the origin of odour episodes through social participation, chemical control and numerical modelling

    NASA Astrophysics Data System (ADS)

    Gallego, E.; Soriano, C.; Roca, F. X.; Perales, J. F.; Alarcón, M.; Guardino, X.

    Odour episodes and environmental air quality are topics of worldwide concern, mainly due to the fact that industrial facilities are often located very close to inhabited areas. Several atmospheric pollutants, mainly volatile organic compounds (VOCs), are responsible for odour episodes of varying degrees of annoyance. A methodology based on the simultaneous application of social participation (by building databases of odour episodes and acquiring air samples), chemical control and the computation of back trajectories allows us to identify the origin of odour episodes. A validated analytical method, based on thermal desorption (TD) coupled with gas chromatography (GC) and mass spectrometry (MS), is used to identify and determine a wide range of VOCs that cause odour nuisance and affect air quality in outdoor air. Back-trajectory modelling is used to track the origin of the air mass responsible for the discomfort backwards in time, mainly to find possible VOC sources outside the urban area. The procedure combines, on one hand, an analytical approach based on the acquisition of samples, which requires the participation of the affected population (which means that social participation is used as a scientific tool), and on the other hand, a modelling approach. Three examples are described to illustrate the methodology.

  16. Molecular basis of human body odour formation: insights deduced from corynebacterial genome sequences.

    PubMed

    Barzantny, H; Brune, I; Tauch, A

    2012-02-01

    During the past few decades, there has been an increased interest in the essential role of commensal skin bacteria in human body odour formation. It is now generally accepted that skin bacteria cause body odour by biotransformation of sweat components secreted in the human axillae. Especially, aerobic corynebacteria have been shown to contribute strongly to axillary malodour, whereas other human skin residents seem to have little influence. Analysis of odoriferous sweat components has shown that the major odour-causing substances in human sweat include steroid derivatives, short volatile branched-chain fatty acids and sulphanylalkanols. In this mini-review, we describe the molecular basis of the four most extensively studied routes of human body odour formation, while focusing on the underlying enzymatic processes. Considering the previously reported role of β-oxidation in odour formation, we analysed the genetic repertoire of eight Corynebacterium species concerning fatty acid metabolism. We particularly focused on the metabolic abilities of the lipophilic axillary isolate Corynebacterium jeikeium K411.

  17. One rhinophore probably provides sufficient sensory input for odour-based navigation by the nudibranch mollusc Tritonia diomedea.

    PubMed

    McCullagh, Gregory B; Bishop, Cory D; Wyeth, Russell C

    2014-12-01

    Tritonia diomedea (synonymous with Tritonia tetraquetra) navigates in turbulent odour plumes, crawling upstream towards prey and downstream to avoid predators. This is probably accomplished by odour-gated rheotaxis, but other possibilities have not been excluded. Our goal was to test whether T. diomedea uses odour-gated rheotaxis and to simultaneously determine which of the cephalic sensory organs (rhinophores and oral veil) are required for navigation. In a first experiment, slugs showed no coherent responses to streams of odour directed at single rhinophores. In a second experiment, navigation in prey and predator odour plumes was compared between animals with unilateral rhinophore lesions, denervated oral veils, or combined unilateral rhinophore lesions and denervated oral veils. In all treatments, animals navigated in a similar manner to that of control and sham-operated animals, indicating that a single rhinophore provides sufficient sensory input for navigation (assuming that a distributed flow measurement system would also be affected by the denervations). Amongst various potential navigational strategies, only odour-gated positive rheotaxis can produce the navigation tracks we observed in prey plumes while receiving input from a single sensor. Thus, we provide strong evidence that T. diomedea uses odour-gated rheotaxis in attractive odour plumes, with odours and flow detected by the rhinophores. In predator plumes, slugs turned downstream to varying degrees rather than orienting directly downstream for crawling, resulting in greater dispersion for negative rheotaxis in aversive plumes. These conclusions are the first explicit confirmation of odour-gated rheotaxis as a navigational strategy in gastropods and are also a foundation for exploring the neural circuits that mediate odour-gated rheotaxis. PMID:25324338

  18. Colour and odour drive fruit selection and seed dispersal by mouse lemurs

    PubMed Central

    Valenta, Kim; Burke, Ryan J.; Styler, Sarah A.; Jackson, Derek A.; Melin, Amanda D.; Lehman, Shawn M.

    2013-01-01

    Animals and fruiting plants are involved in a complex set of interactions, with animals relying on fruiting trees as food resources, and fruiting trees relying on animals for seed dispersal. This interdependence shapes fruit signals such as colour and odour, to increase fruit detectability, and animal sensory systems, such as colour vision and olfaction to facilitate food identification and selection. Despite the ecological and evolutionary importance of plant-animal interactions for shaping animal sensory adaptations and plant characteristics, the details of the relationship are poorly understood. Here we examine the role of fruit chromaticity, luminance and odour on seed dispersal by mouse lemurs. We show that both fruit colour and odour significantly predict fruit consumption and seed dispersal by Microcebus ravelobensis and M. murinus. Our study is the first to quantify and examine the role of bimodal fruit signals on seed dispersal in light of the sensory abilities of the disperser. PMID:23939534

  19. Mate-odour identification by both sexes of Evarcha culicivora, an East African jumping spider.

    PubMed

    Cross, Fiona R; Jackson, Robert R

    2009-05-01

    Evarcha culicivora is an unusual salticid spider because each sex actively courts the other and both sexes make distinctive mate-choice decisions. Here we use olfactometer experiments for investigating the ability of each sex to identify potential mates on the basis of odour alone. Test spiders spent more time in the vicinity of opposite-sex conspecific source spiders, regardless of whether or not these source spiders had previously mated, when the alternatives were conspecific individuals of the same sex, juveniles or a control (no odour source). This trend held regardless of the test spider's and source spider's age after reaching maturity and, for male test spiders, it held regardless of the test spider's mating status. However, after females had mated they no longer expressed a preference for male odour. PMID:19429199

  20. Colour and odour drive fruit selection and seed dispersal by mouse lemurs.

    PubMed

    Valenta, Kim; Burke, Ryan J; Styler, Sarah A; Jackson, Derek A; Melin, Amanda D; Lehman, Shawn M

    2013-01-01

    Animals and fruiting plants are involved in a complex set of interactions, with animals relying on fruiting trees as food resources, and fruiting trees relying on animals for seed dispersal. This interdependence shapes fruit signals such as colour and odour, to increase fruit detectability, and animal sensory systems, such as colour vision and olfaction to facilitate food identification and selection. Despite the ecological and evolutionary importance of plant-animal interactions for shaping animal sensory adaptations and plant characteristics, the details of the relationship are poorly understood. Here we examine the role of fruit chromaticity, luminance and odour on seed dispersal by mouse lemurs. We show that both fruit colour and odour significantly predict fruit consumption and seed dispersal by Microcebus ravelobensis and M. murinus. Our study is the first to quantify and examine the role of bimodal fruit signals on seed dispersal in light of the sensory abilities of the disperser.

  1. Shades of yellow: interactive effects of visual and odour cues in a pest beetle

    PubMed Central

    Stevenson, Philip C.; Belmain, Steven R.

    2016-01-01

    Background: The visual ecology of pest insects is poorly studied compared to the role of odour cues in determining their behaviour. Furthermore, the combined effects of both odour and vision on insect orientation are frequently ignored, but could impact behavioural responses. Methods: A locomotion compensator was used to evaluate use of different visual stimuli by a major coleopteran pest of stored grains (Sitophilus zeamais), with and without the presence of host odours (known to be attractive to this species), in an open-loop setup. Results: Some visual stimuli—in particular, one shade of yellow, solid black and high-contrast black-against-white stimuli—elicited positive orientation behaviour from the beetles in the absence of odour stimuli. When host odours were also present, at 90° to the source of the visual stimulus, the beetles presented with yellow and vertical black-on-white grating patterns changed their walking course and typically adopted a path intermediate between the two stimuli. The beetles presented with a solid black-on-white target continued to orient more strongly towards the visual than the odour stimulus. Discussion: Visual stimuli can strongly influence orientation behaviour, even in species where use of visual cues is sometimes assumed to be unimportant, while the outcomes from exposure to multimodal stimuli are unpredictable and need to be determined under differing conditions. The importance of the two modalities of stimulus (visual and olfactory) in food location is likely to depend upon relative stimulus intensity and motivational state of the insect. PMID:27478707

  2. Prospects for developing odour baits to control Glossina fuscipes spp., the major vector of human African trypanosomiasis.

    PubMed

    Omolo, Maurice O; Hassanali, Ahmed; Mpiana, Serge; Esterhuizen, Johan; Lindh, Jenny; Lehane, Mike J; Solano, Philippe; Rayaisse, Jean Baptiste; Vale, Glyn A; Torr, Steve J; Tirados, Inaki

    2009-01-01

    We are attempting to develop cost-effective control methods for the important vector of sleeping sickness, Glossina fuscipes spp. Responses of the tsetse flies Glossina fuscipes fuscipes (in Kenya) and G. f. quanzensis (in Democratic Republic of Congo) to natural host odours are reported. Arrangements of electric nets were used to assess the effect of cattle-, human- and pig-odour on (1) the numbers of tsetse attracted to the odour source and (2) the proportion of flies that landed on a black target (1x1 m). In addition responses to monitor lizard (Varanus niloticus) were assessed in Kenya. The effects of all four odours on the proportion of tsetse that entered a biconical trap were also determined. Sources of natural host odour were produced by placing live hosts in a tent or metal hut (volumes approximately 16 m(3)) from which the air was exhausted at approximately 2000 L/min. Odours from cattle, pigs and humans had no significant effect on attraction of G. f. fuscipes but lizard odour doubled the catch (P<0.05). Similarly, mammalian odours had no significant effect on landing or trap entry whereas lizard odour increased these responses significantly: landing responses increased significantly by 22% for males and 10% for females; the increase in trap efficiency was relatively slight (5-10%) and not always significant. For G. f. quanzensis, only pig odour had a consistent effect, doubling the catch of females attracted to the source and increasing the landing response for females by approximately 15%. Dispensing CO(2) at doses equivalent to natural hosts suggested that the response of G. f. fuscipes to lizard odour was not due to CO(2). For G. f. quanzensis, pig odour and CO(2) attracted similar numbers of tsetse, but CO(2) had no material effect on the landing response. The results suggest that identifying kairomones present in lizard odour for G. f. fuscipes and pig odour for G. f. quanzensis may improve the performance of targets for controlling these species

  3. Prospects for Developing Odour Baits To Control Glossina fuscipes spp., the Major Vector of Human African Trypanosomiasis

    PubMed Central

    Omolo, Maurice O.; Hassanali, Ahmed; Mpiana, Serge; Esterhuizen, Johan; Lindh, Jenny; Lehane, Mike J.; Solano, Philippe; Rayaisse, Jean Baptiste; Vale, Glyn A.; Torr, Steve J.; Tirados, Inaki

    2009-01-01

    We are attempting to develop cost-effective control methods for the important vector of sleeping sickness, Glossina fuscipes spp. Responses of the tsetse flies Glossina fuscipes fuscipes (in Kenya) and G. f. quanzensis (in Democratic Republic of Congo) to natural host odours are reported. Arrangements of electric nets were used to assess the effect of cattle-, human- and pig-odour on (1) the numbers of tsetse attracted to the odour source and (2) the proportion of flies that landed on a black target (1×1 m). In addition responses to monitor lizard (Varanus niloticus) were assessed in Kenya. The effects of all four odours on the proportion of tsetse that entered a biconical trap were also determined. Sources of natural host odour were produced by placing live hosts in a tent or metal hut (volumes≈16 m3) from which the air was exhausted at ∼2000 L/min. Odours from cattle, pigs and humans had no significant effect on attraction of G. f. fuscipes but lizard odour doubled the catch (P<0.05). Similarly, mammalian odours had no significant effect on landing or trap entry whereas lizard odour increased these responses significantly: landing responses increased significantly by 22% for males and 10% for females; the increase in trap efficiency was relatively slight (5–10%) and not always significant. For G. f. quanzensis, only pig odour had a consistent effect, doubling the catch of females attracted to the source and increasing the landing response for females by ∼15%. Dispensing CO2 at doses equivalent to natural hosts suggested that the response of G. f. fuscipes to lizard odour was not due to CO2. For G. f. quanzensis, pig odour and CO2 attracted similar numbers of tsetse, but CO2 had no material effect on the landing response. The results suggest that identifying kairomones present in lizard odour for G. f. fuscipes and pig odour for G. f. quanzensis may improve the performance of targets for controlling these species. PMID:19434232

  4. Early recognition of speech

    PubMed Central

    Remez, Robert E; Thomas, Emily F

    2013-01-01

    Classic research on the perception of speech sought to identify minimal acoustic correlates of each consonant and vowel. In explaining perception, this view designated momentary components of an acoustic spectrum as cues to the recognition of elementary phonemes. This conceptualization of speech perception is untenable given the findings of phonetic sensitivity to modulation independent of the acoustic and auditory form of the carrier. The empirical key is provided by studies of the perceptual organization of speech, a low-level integrative function that finds and follows the sensory effects of speech amid concurrent events. These projects have shown that the perceptual organization of speech is keyed to modulation; fast; unlearned; nonsymbolic; indifferent to short-term auditory properties; and organization requires attention. The ineluctably multisensory nature of speech perception also imposes conditions that distinguish language among cognitive systems. WIREs Cogn Sci 2013, 4:213–223. doi: 10.1002/wcs.1213 PMID:23926454

  5. Women's preference for dominant male odour: effects of menstrual cycle and relationship status

    PubMed Central

    Havlicek, Jan; Roberts, S. Craig; Flegr, Jaroslav

    2005-01-01

    Body odour may provide significant cues about a potential sexual partner's genetic quality, reproductive status and health. In animals, a key trait in a female's choice of sexual partner is male dominance but, to date, this has not been examined in humans. Here, we show that women in the fertile phase of their cycle prefer body odour of males who score high on a questionnaire-based dominance scale (international personality items pool). In accordance with the theory of mixed mating strategies, this preference varies with relationship status, being much stronger in fertile women in stable relationships than in fertile single women. PMID:17148181

  6. Odour reduction strategies for biosolids produced from a Western Australian wastewater treatment plant: results from Phase I laboratory trials.

    PubMed

    Gruchlik, Yolanta; Heitz, Anna; Joll, Cynthia; Driessen, Hanna; Fouché, Lise; Penney, Nancy; Charrois, Jeffrey W A

    2013-01-01

    This study investigated sources of odours from biosolids produced from a Western Australian wastewater treatment plant and examined possible strategies for odour reduction, specifically chemical additions and reduction of centrifuge speed on a laboratory scale. To identify the odorous compounds and assess the effectiveness of the odour reduction measures trialled in this study, headspace solid-phase microextraction gas chromatography-mass spectrometry (HS SPME-GC-MS) methods were developed. The target odour compounds included volatile sulphur compounds (e.g. dimethyl sulphide, dimethyl disulphide and dimethyl trisulphide) and other volatile organic compounds (e.g. toluene, ethylbenzene, styrene, p-cresol, indole and skatole). In our laboratory trials, aluminium sulphate added to anaerobically digested sludge prior to dewatering offered the best odour reduction strategy amongst the options that were investigated, resulting in approximately 40% reduction in the maximum concentration of the total volatile organic sulphur compounds, relative to control. PMID:24355840

  7. Relationship between odour-active compounds and flavour perception in meat from lambs fed different diets.

    PubMed

    Resconi, Virginia C; Campo, M Mar; Montossi, Fabio; Ferreira, Vicente; Sañudo, Carlos; Escudero, Ana

    2010-08-01

    To identify the most important aroma compounds in 20d-aged meat from castrated heavy Corriedale lambs fed one of four diets, grilled loin samples were subjected to a dynamic headspace-solid phase extraction (DHS-SPE) and gas chromatography-olfactometry (GC-O). Most of the important odorants were aldehydes and ketones. To evaluate the effect of finishing diet on carbonyl compounds, a derivatization of the headspace carbonyls using o-[(2,3,4,5,6-pentafluorophenyl)methyl]hydroxylamine hydrochloride (PFBHA) and analysis by GC-MS was conducted. Diet did not affect aliphatic saturated aldehydes. The meat from lambs finished on pastures, without a concentrate supplement, had very low concentrations of lipid-derived unsaturated aldehydes and ketones and Strecker aldehydes, possibly because of the protective effect of antioxidants that occur in the diet naturally. Lamb flavour was related to the concentration of heptan-2-one and oct-1-en-3-one, but rancid or undesirable flavours were not related to the abundance of carbonyl compounds. PMID:20416794

  8. Behavioural responses of stable flies to cattle manure slurry associated odourants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stable flies (Stomoxys calcitrans [Diptera: Muscidae] L.) are blood-feeding synanthropic pests, which cause significant economic losses in livestock. Stable fly antennae contain olfactory sensilla responsive to host and host environment-associated odours. Field observation indicated that the abundan...

  9. Identification of the odour and chemical composition of alumina refinery air emissions.

    PubMed

    Coffey, P S; Ioppolo-Armanios, M

    2004-01-01

    Alcoa World Alumina Australia has undertaken comprehensive air emissions monitoring aimed at characterising and quantifying the complete range of emissions to the atmosphere from Bayer refining of alumina at its Western Australian refineries. To the best of our knowledge, this project represents the most complete air emissions inventory of a Bayer refinery conducted in the worldwide alumina industry. It adds considerably to knowledge of air emission factors available for use in emissions estimation required under national pollutant release and transfer registers (NPRTs), such as the Toxic Releases Inventory, USA, and the National Pollutant Inventory, Australia. It also allows the preliminary identification of the key chemical components responsible for characteristic alumina refinery odours and the contribution of these components to the quality, or hedonic tone, of the odours. The strength and acceptability of refinery odours to employees and neighbours appears to be dependent upon where and in what proportion the odorous gases have been emitted from the refineries. This paper presents the results of the programme and develops a basis for classifying the odour properties of the key emission sources in the alumina-refining process.

  10. Unconscious Odour Conditioning 25 Years Later: Revisiting and Extending "Kirk-Smith, Van Toller and Dodd"

    ERIC Educational Resources Information Center

    Zucco, Gesualdo M.; Paolini, Michela; Schaal, Benoist

    2009-01-01

    The pioneering work by Kirk-Smith, Van Toller, and Dodd [Kirk-Smith, M. D., Van Toller, C., & Dodd, G. H. (1983). "Unconscious odour conditioning in human subjects." "Biological Psychology," 17, 221-231], established that an unnoticed odorant paired with an emotionally meaningful task can influence mood and attitudes when the odorant alone is…

  11. Advances in the use of odour as forensic evidence through optimizing and standardizing instruments and canines

    PubMed Central

    Furton, Kenneth G.; Caraballo, Norma Iris; Cerreta, Michelle M.; Holness, Howard K.

    2015-01-01

    This paper explores the advances made in identifying trace amounts of volatile organic compounds (VOCs) that originate from forensic specimens, such as drugs, explosives, live human scent and the scent of death, as well as the probative value for detecting such odours. The ability to locate and identify the VOCs liberated from or left by forensic substances is of increasing importance to criminal investigations as it can indicate the presence of contraband and/or associate an individual to a particular location or object. Although instruments have improved significantly in recent decades—with sensitivities now rivalling that of biological detectors—it is widely recognized that canines are generally still more superior for the detection of odourants due to their speed, versatility, ruggedness and discriminating power. Through advancements in the detection of VOCs, as well as increased standardization efforts for instruments and canines, the reliability of odour as evidence has continuously improved and is likely to continue to do so. Moreover, several legal cases in which this novel form of evidence has been accepted into US courts of law are discussed. As the development and implementation of best practice guidelines for canines and instruments increase, their reliability in detecting VOCs of interest should continue to improve, expanding the use of odour as an acceptable form of forensic evidence. PMID:26101287

  12. Exposure to extreme stress impairs contextual odour discrimination in an animal model of PTSD.

    PubMed

    Cohen, Hagit; Liberzon, Israel; Richter-Levin, Gal

    2009-04-01

    Post-traumatic stress disorder (PTSD) patients respond to trauma-related danger cues even in objectively safe environments as if they were in the original event, seemingly unable to adequately modulate their responses based on the contextual cues present. In order to model this inability to utilize contextualized memory, in an animal model of PTSD, a novel experimental paradigm of contextual cue processing was developed--the differential contextual odour conditioning (DCOC) paradigm--and tested in trauma-exposed animals and controls. In the DCOC paradigm, animals encountered cinnamon odour in both an aversive environment and a rewarding (safe) environment. Response (freezing) to cinnamon odour was tested in a third, neutral environment to examine the ability of animals to modulate their responses based on the contextual cues. The effect of exposure to traumatic stressors, e.g. predator scent stress (PSS) and underwater trauma (UWT), on contextual cue discrimination was assessed. Rats trained in the DCOC paradigm acquired the ability to modulate their behavioural responses to odour cue based on contextual cues signalling safe vs. dangerous environment. The PSS and UWT stressors abolished the ability to modulate their responses based on contextual cues, both when exposure preceded DCOC training, and when it followed successfully completed training. The DCOC paradigm offers a promising model for studying the neurobiological basis of contextual modulation of response to potential threat in animals, a process that is disrupted by exposure to severe stress/trauma, and thus might be particularly salient for the study of PTSD. PMID:18700055

  13. Design and validation of a wind tunnel system for odour sampling on liquid area sources.

    PubMed

    Capelli, L; Sironi, S; Del Rosso, R; Céntola, P

    2009-01-01

    The aim of this study is to describe the methods adopted for the design and the experimental validation of a wind tunnel, a sampling system suitable for the collection of gaseous samples on passive area sources, which allows to simulate wind action on the surface to be monitored. The first step of the work was the study of the air velocity profiles. The second step of the work consisted in the validation of the sampling system. For this purpose, the odour concentration of some air samples collected by means of the wind tunnel was measured by dynamic olfactometry. The results of the air velocity measurements show that the wind tunnel design features enabled the achievement of a uniform and homogeneous air flow through the hood. Moreover, the laboratory tests showed a very good correspondence between the odour concentration values measured at the wind tunnel outlet and the odour concentration values predicted by the application of a specific volatilization model, based on the Prandtl boundary layer theory. The agreement between experimental and theoretical trends demonstrate that the studied wind tunnel represents a suitable sampling system for the simulation of specific odour emission rates from liquid area sources without outward flow.

  14. Factors influencing separation distances against odour annoyance calculated by Gaussian and Lagrangian dispersion models

    NASA Astrophysics Data System (ADS)

    Piringer, Martin; Knauder, Werner; Petz, Erwin; Schauberger, Günther

    2016-09-01

    Direction-dependent separation distances to avoid odour annoyance, calculated with the Gaussian Austrian Odour Dispersion Model AODM and the Lagrangian particle diffusion model LASAT at two sites, are analysed and compared. The relevant short-term peak odour concentrations are calculated with a stability-dependent peak-to-mean algorithm. The same emission and meteorological data, but model-specific atmospheric stability classes are used. The estimate of atmospheric stability is obtained from three-axis ultrasonic anemometers using the standard deviations of the three wind components and the Obukhov stability parameter. The results are demonstrated for the Austrian villages Reidling and Weissbach with very different topographical surroundings and meteorological conditions. Both the differences in the wind and stability regimes as well as the decrease of the peak-to-mean factors with distance lead to deviations in the separation distances between the two sites. The Lagrangian model, due to its model physics, generally calculates larger separation distances. For worst-case calculations necessary with environmental impact assessment studies, the use of a Lagrangian model is therefore to be preferred over that of a Gaussian model. The study and findings relate to the Austrian odour impact criteria.

  15. Study of the effect of DMSO on VOS odour production in a wastewater plant.

    PubMed

    Cheng, X; Peterkin, E D; Burlingame, G A

    2007-01-01

    Odours caused by volatile organic sulphides (VOS) have a history spanning over 20 years for Philadelphia's Northeast Water Pollution Control Plant (NEWPCP). A "canned corn" type of odour has caused residential complaints. Traditional odour control approaches based on hydrogen sulphide failed. This study confirmed that dimethyl sulphoxide (DMSO) from a chemical facility was the dominant cause of the "canned corn" nuisance odour in the form of dimethyl sulphide (DMS). During a discharge, DMSO concentrations up to 12 mg/L were found in the influent of the NEWPCP. Each DMSO concentration peak induced a DMS peak. DMS concentrations increased from less than 50 microg/L to 6 mg/L with a corresponding decrease in DMSO. Approximately 79% of DMSO from the primary sedimentation influent was passed to the effluent, and to downstream processes, such as the aeration tanks where the DMS was volatilised by the aeration. The DMS partial pressure in ambient air of NEWPCP can be between 0.03 and 0.18 x 10(-3) atm during a DMSO discharge. From the above information, the potential of VOS production is estimated and a practical plan for remediation can be designed. PMID:17489426

  16. Ca(2+)-BK channel clusters in olfactory receptor neurons and their role in odour coding.

    PubMed

    Bao, Guobin; de Jong, Daniëlle; Alevra, Mihai; Schild, Detlev

    2015-12-01

    Olfactory receptor neurons (ORNs) have high-voltage-gated Ca(2+) channels whose physiological impact has remained enigmatic since the voltage-gated conductances in this cell type were first described in the 1980s. Here we show that in ORN somata of Xenopus laevis tadpoles these channels are clustered and co-expressed with large-conductance potassium (BK) channels. We found approximately five clusters per ORN and twelve Ca(2+) channels per cluster. The action potential-triggered activation of BK channels accelerates the repolarization of action potentials and shortens interspike intervals during odour responses. This increases the sensitivity of individual ORNs to odorants. At the level of mitral cells of the olfactory bulb, odour qualities have been shown to be coded by first-spike-latency patterns. The system of Ca(2+) and BK channels in ORNs appears to be important for correct odour coding because the blockage of BK channels not only affects ORN spiking patterns but also changes the latency pattern representation of odours in the olfactory bulb.

  17. Advances in the use of odour as forensic evidence through optimizing and standardizing instruments and canines.

    PubMed

    Furton, Kenneth G; Caraballo, Norma Iris; Cerreta, Michelle M; Holness, Howard K

    2015-08-01

    This paper explores the advances made in identifying trace amounts of volatile organic compounds (VOCs) that originate from forensic specimens, such as drugs, explosives, live human scent and the scent of death, as well as the probative value for detecting such odours. The ability to locate and identify the VOCs liberated from or left by forensic substances is of increasing importance to criminal investigations as it can indicate the presence of contraband and/or associate an individual to a particular location or object. Although instruments have improved significantly in recent decades-with sensitivities now rivalling that of biological detectors-it is widely recognized that canines are generally still more superior for the detection of odourants due to their speed, versatility, ruggedness and discriminating power. Through advancements in the detection of VOCs, as well as increased standardization efforts for instruments and canines, the reliability of odour as evidence has continuously improved and is likely to continue to do so. Moreover, several legal cases in which this novel form of evidence has been accepted into US courts of law are discussed. As the development and implementation of best practice guidelines for canines and instruments increase, their reliability in detecting VOCs of interest should continue to improve, expanding the use of odour as an acceptable form of forensic evidence.

  18. Prior classical olfactory conditioning improves odour-cued flight orientation of honey bees in a wind tunnel.

    PubMed

    Chaffiol, Antoine; Laloi, David; Pham-Delègue, Minh-Hà

    2005-10-01

    Odours are key cues used by the honey bee in various situations. They play an important role in sexual attraction, social behaviour and location of profitable food sources. Here, we were interested in the role of odours in orientation at short distance, for instance the approach flight to a floral patch or in close proximity to the hive entrance. Using a newly designed wind tunnel, we investigated the orientation behaviour of the bee towards two different odours: a social odour and a floral component, linalool. We then tested the effect of prior olfactory conditioning (conditioning of the proboscis extension reflex) on subsequent flight orientation. We showed that both stimuli induced orientated behaviour (orientated flights, circling around the odour source) in up to 70% of the worker bees, social odour being slightly more attractive than the linalool. We found thereafter that orientation performance towards the floral compound can be significantly enhanced by prior classical olfactory learning. This type of information transfer, from a Pavlovian associative context to an orientation task, might allow future foragers to acquire, within the hive, relevant information about the odours and food they will encounter during their later foraging bouts.

  19. Data-driven honeybee antennal lobe model suggests how stimulus-onset asynchrony can aid odour segregation.

    PubMed

    Nowotny, Thomas; Stierle, Jacob S; Galizia, C Giovanni; Szyszka, Paul

    2013-11-01

    Insects have a remarkable ability to identify and track odour sources in multi-odour backgrounds. Recent behavioural experiments show that this ability relies on detecting millisecond stimulus asynchronies between odourants that originate from different sources. Honeybees, Apis mellifera, are able to distinguish mixtures where both odourants arrive at the same time (synchronous mixtures) from those where odourant onsets are staggered (asynchronous mixtures) down to an onset delay of only 6ms. In this paper we explore this surprising ability in a model of the insects' primary olfactory brain area, the antennal lobe. We hypothesize that a winner-take-all inhibitory network of local neurons in the antennal lobe has a symmetry-breaking effect, such that the response pattern in projection neurons to an asynchronous mixture is different from the response pattern to the corresponding synchronous mixture for an extended period of time beyond the initial odourant onset where the two mixture conditions actually differ. The prolonged difference between response patterns to synchronous and asynchronous mixtures could facilitate odoursegregation in downstream circuits of the olfactory pathway. We present a detailed data-driven model of the bee antennal lobe that reproduces a large data set of experimentally observed physiological odour responses, successfully implements the hypothesised symmetry-breaking mechanism and so demonstrates that this mechanism is consistent with our current knowledge of the olfactory circuits in the bee brain. This article is part of a Special Issue entitled Neural Coding 2012.

  20. The importance of interhemispheric transfer for foveal vision: a factor that has been overlooked in theories of visual word recognition and object perception.

    PubMed

    Brysbaert, Marc

    2004-03-01

    In this special issue of Brain and Language, we examine what implications the division between the left and the right brain half has for the recognition of words presented in the center of the visual field. The different articles are a first indication that taking into account the split between the left and the right cerebral hemisphere need not be an inescapable nuisance in models of visual word recognition but may in fact form the clue to the solution of a longstanding problem within this literature. Also, the fact that interhemispheric transfer has implications for foveal word recognition should interest laterality researchers, as it makes their findings more central to normal reading. In this introductory article, I first present a rough picture of the current (lack of) evidence for a bilateral representation of the fovea and the absence of a callosal delay. I then briefly discuss the suggestions made by the different authors on how to integrate the foveal split within current models of visual word recognition. PMID:14967210

  1. Odour enrichment increases adult-born dopaminergic neurons in the mouse olfactory bulb.

    PubMed

    Bonzano, Sara; Bovetti, Serena; Fasolo, Aldo; Peretto, Paolo; De Marchis, Silvia

    2014-11-01

    The olfactory bulb (OB) is the first brain region involved in the processing of olfactory information. In adult mice, the OB is highly plastic, undergoing cellular/molecular dynamic changes that are modulated by sensory experience. Odour deprivation induces down-regulation of tyrosine hydroxylase (TH) expression in OB dopaminergic interneurons located in the glomerular layer (GL), resulting in decreased dopamine in the OB. Although the effect of sensory deprivation is well established, little is known about the influence of odour enrichment on dopaminergic cells. Here we report that prolonged odour enrichment on C57BL/6J strain mice selectively increases TH-immunopositive cells in the GL by nearly 20%. Following odour enrichment on TH-green fluorescent protein (GFP) transgenic mice, in which GFP identified both mature TH-positive cells and putative immature dopaminergic cells expressing TH mRNA but not TH protein, we found a similar 20% increase in GFP-expressing cells, with no changes in the ratio between TH-positive and TH-negative cells. These data suggest that enriched conditions induce an expansion in the whole dopaminergic lineage. Accordingly, by using 5-bromo-2-deoxyuridine injections to label adult-generated cells in the GL of TH-GFP mice, we found an increase in the percentage of 5-bromo-2-deoxyuridine-positive dopaminergic cells in enriched compared with control conditions, whereas no differences were found for calretinin- and calbindin-positive subtypes. Strikingly, the fraction of newborn cells among the dopaminergic population doubled in enriched conditions. On the whole, our results demonstrate that odour enrichment drives increased integration of adult-generated dopaminergic cells that could be critical to adapt the OB circuits to the environmental incoming information.

  2. Modulation by cyclic GMP of the odour sensitivity of vertebrate olfactory receptor cells

    NASA Technical Reports Server (NTRS)

    Leinders-Zufall, T.; Shepherd, G. M.; Zufall, F.

    1996-01-01

    Recent evidence has indicated a significant role for the cGMP second messenger system in vertebrate olfactory transduction but no clear functions have been identified for cGMP so far. Here, we have examined the effects of 8-Br-cGMP and carbon monoxide (CO) on odour responses of salamander olfactory receptor neurons using perforated patch recordings. We report that 8-Br-cGMP strongly down-regulates the odour sensitivity of the cells, with a K1/2 of 460 nM. This adaptation-like effect can be mimicked by CO, an activator of soluble guanylyl cyclase, with a K1/2 of 1 microM. Sensitivity modulation is achieved through a regulatory chain of events in which cGMP stimulates a persistent background current due to the activation of cyclic nucleotide-gated channels. This in turn leads to sustained Ca2+ entry providing a negative feedback signal. One consequence of the Ca2+ entry is a shift to the right of the stimulus-response curve and a reduction in saturating odour currents. Together, these two effects can reduce the sensory generator current by up to twenty-fold. Thus, cGMP functions to control the gain of the G-protein coupled cAMP pathway. Another consequence of the action of cGMP is a marked prolongation of the odour response kinetics. The effects of CO/cGMP are long-lasting and can continue for minutes. Hence, we propose that cGMP helps to prevent saturation of the cell's response by adjusting the operational range of the cAMP cascade and contributes to olfactory adaptation by decreasing the sensitivity of olfactory receptor cells to repeated odour stimuli.

  3. Zoophily of Anopheles arabiensis and An. gambiae in Madagascar demonstrated by odour-baited entry traps.

    PubMed

    Duchemin, J B; Tsy, J M; Rabarison, P; Roux, J; Coluzzi, M; Costantini, C

    2001-03-01

    In Madagascar we used odour-baited entry traps (OBETs) for host choice tests of wild female anopheline mosquitoes (Diptera: Culicidae) at representative localities on the East and West sides of the island (villages Fenoarivo and Tsararano, respectively) and at the southern margin of the central plateau (Zazafotsy village, 800 m altitude). No insecticide house-spraying operations have been undertaken at these villages. Odours from a man and a calf of similar mass, concealed in different tents, were drawn by fans into separate OBETs set side by side. Traps were alternated to compensate for position effects, and different pairs of individual baits were employed for successive replicates. Totals of 266 An. funestus Giles sensu stricto and 362 An. gambiae Giles sensu lato were collected in 48 trap nights during March-June 1999. For each mosquito species the 'index of anthropophily' was defined as the proportion of females caught in the human-baited trap. For An. funestus this index was found to be consistently greater than 0.5 (value for random choice between traps/hosts), indicating that this species 'preferred' human to calf odour (index=0.83). Conversely, the index of anthropophily for An. gambiae s.l. indicated they 'chose' calf in preference to human odour (index=0.26). No significant differences of relative preference for calf or man were detected between villages; geographical variance accounted for <8% of the total experimental variance. Molecular identifications of 181 specimens of the An. gambiae complex (approximately 50% of the samples) revealed only An. arabiensis Patton at Tsararano and Zazafotsy, but >97% An. gambiae Giles sensu stricto at Fenoarivo, in accordance with prior knowledge of the differential distributions of these sibling species on the island. Predominant zoophily (i.e. intrinsic 'preference' for cattle odours) by both An. arabiensis and An. gambiae s.s. in Madagascar contrasts with their greater anthropophily in continental Africa.

  4. Natural host odours as possible attractants for Glossina tachinoides and G. longipalpis (Diptera: Glossinidae).

    PubMed

    Späth, J

    1997-11-01

    As strictly haematophagous insects, tsetse flies feed on a wide variety of wild and domestic animals. Although these are mainly mammals, some tsetse species also feed on reptiles. The present study investigated whether the odours of several potential natural tsetse hosts may be used as novel attractants to improve the catch of Glossina tachinoides or G. longipalpis in biconical traps. The odour of a living monitor lizard (Varanus niloticus) had no effect on the catch of G. tachinoides. Hexane skin washings of monitor lizard and warthog (Phacochoerus aethiopicus) dispensed in small quantities improved the catch of G. tachinoides significantly by factors of up to 1.34 and 1.46, respectively. Skin washing of bushbuck (Tragelaphus scriptus) did not increase the catch of G. tachinoides, but the synthetic phenolic fraction of bushbuck urine enhanced it significantly by 1.81 times. The catch of G. longipalpis was improved significantly by the urines of warthog, domestic pig and bushbuck by factors of 1.58, 1.91 and 2.51, respectively. In relation to the quantity of evaporated odour, bushbuck and warthog urine seem to be of particular interest for further attractant studies. The effect of tested host odours on the catch of G. tachinoides and G. longipalpis is compared with data of other tsetse species and with the frequency these hosts are fed on by tsetse flies. Bushbuck is one of the principal natural hosts of both Glossina species investigated, and of all odours tested, bushbuck urine and its synthetic phenolic fraction improved the catch of both tsetse species the most. PMID:9386790

  5. Synaesthesia or vivid imagery? A single case fMRI study of visually induced olfactory perception.

    PubMed

    Chan, Jason S; van den Bosch, Jasper J F; Theves, Stephanie; Hardt, Stefanie; Pflanz, Patrick; Lötsch, Jörn; Kaiser, Jochen; Naumer, Marcus J

    2014-01-01

    The most common form of synaesthesia is grapheme-colour synaesthesia. However, rarer forms of synaesthesia also exist, such as word-gustatory and olfactory-gustatory synaesthesia, whereby a word or smell will induce a specific. In this study we describe a single individual (LJ) who experiences a concurrent olfactory stimulus when presented with congruent visual images. For some visual stimuli, he perceives a strong and automatic olfactory percept, which has existed throughout his life. In this study, we explore whether his experiences are a new form of synaesthesia or simply vivid imagery. Unlike other forms of synaesthesia, the concurrent odour is congruent to the visual inducer. For example, a photograph of dress shoes will elicit the smell of leather. We presented LJ and several control participants with 75 images of everyday objects. Their task was to indicate the strength of any perceived odours induced by the visual images. LJ rated several of the images as inducing a concurrent odour, while controls did not have any such percept. Images that LJ reported as inducing the strongest odours were used, along with colour-matched control images, in the context of an fMRI experiment. Participants were given a one-back task to maintain attention. A block-design odour localizer was presented to localize the piriform cortex (primary olfactory cortex). We found an increased BOLD response in the piriform cortex for the odour-inducing images compared to the control images in LJ. There was no difference in BOLD response between these two stimulus types in the control participants. A subsequent olfactory imagery task did not elicit enhanced activity in the piriform cortex in LJ, suggesting his perceptual experiences may not be based on olfactory imagery. PMID:25577904

  6. Disinhibition of olfactory bulb granule cells accelerates odour discrimination in mice

    PubMed Central

    Nunes, Daniel; Kuner, Thomas

    2015-01-01

    Granule cells are the dominant cell type of the olfactory bulb inhibiting mitral and tufted cells via dendrodendritic synapses; yet the factors regulating the strength of their inhibitory output, and, therefore, their impact on odour discrimination, remain unknown. Here we show that GABAAR β3-subunits are distributed in a somatodendritic pattern, mostly sparing the large granule cell spines also known as gemmules. Granule cell-selective deletion of β3-subunits nearly abolishes spontaneous and muscimol-induced currents mediated by GABAA receptors in granule cells, yet recurrent inhibition of mitral cells is strongly enhanced. Mice with disinhibited granule cells require less time to discriminate both dissimilar as well as highly similar odourants, while discrimination learning remains unaffected. Hence, granule cells are controlled by an inhibitory drive that in turn tunes mitral cell inhibition. As a consequence, the olfactory bulb inhibitory network adjusts the speed of early sensory processing. PMID:26592770

  7. [Faces affect recognition in schizophrenia].

    PubMed

    Prochwicz, Katarzyna; Rózycka, Jagoda

    2012-01-01

    Clinical observations and the results of many experimental researches indicate that individuals suffering from schizophrenia reveal difficulties in the recognition of emotional states experienced by other people; however the causes and the range of these problems have not been clearly described. Despite early research results confirming that difficulties in emotion recognition are related only to negative emotions, the results of the researches conducted over the lat 30 years indicate that emotion recognition problems are a manifestation of a general cognitive deficit, and they do not concern specific emotions. The article contains a review of the research on face affect recognition in schizophrenia. It discusses the causes of these difficulties, the differences in the accuracy of the recognition of specific emotions, the relationship between the symptoms of schizophrenia and the severity of problems with face perception, and the types of cognitive processes which influence the disturbances in face affect recognition. Particular attention was paid to the methodology of the research on face affect recognition, including the methods used in control tasks relying on the identification of neutral faces designed to assess the range of deficit underlying the face affect recognition problems. The analysis of methods used in particular researches revealed some weaknesses. The article also deals with the question of the possibilities of improving the ability to recognise the emotions, and briefly discusses the efficiency of emotion recognition training programs designed for patients suffering from schizophrenia.

  8. Cumulative effects of noise and odour annoyances on environmental and health related quality of life.

    PubMed

    Oiamo, Tor H; Luginaah, Isaac N; Baxter, Jamie

    2015-12-01

    Noise and odour annoyances are important considerations in research on health effects of air pollution and traffic noise. Cumulative exposures can occur via several chemical hazards or a combination of chemical and stressor-based hazards, and related health outcomes can be generalized as manifestations of physiological and/or psychological stress responses. A major research challenge in this field is to understand the combined health effects of physiological and psychological responses to exposure. The SF-12 Health Survey is a health related quality of life (HRQoL) instrument designed for the assessment of functional mental and physical health in clinical practice and therefore well suited to research on physiological health outcomes of exposure. However, previous research has not assessed its sensitivity to psychological stress as measured by noise annoyance and odour annoyance. The current study validated and tested this application of the SF-12 Health Survey in a cross-sectional study (n = 603) that included exposure assessment for traffic noise and air pollution in Windsor, Ontario, Canada. The results indicated that SF-12 scores in Windsor were lower than Canadian normative data. A structural equation model demonstrated that this was partially due to noise and odour annoyances, which were associated with covarying exposures to ambient nitrogen dioxide and traffic noise. More specifically, noise annoyance had a significant and negative effect on both mental and physical health factors of the SF-12 and there was a significant covariance between noise annoyance and odour annoyance. The study confirmed a significant effect of psychological responses to cumulative exposures on HRQoL. The SF-12 Health Survey shows promise with respect to assessing the cumulative health effects of outdoor air pollution and traffic noise.

  9. Impact of a non-attentively perceived odour on subsequent food choices.

    PubMed

    Gaillet-Torrent, M; Sulmont-Rossé, C; Issanchou, S; Chabanet, C; Chambaron, S

    2014-05-01

    Current research in psychology suggests that unconscious processes influence a significant proportion of choices and decisions. To study the impact of a non-attentively perceived odour on food choices, we used a priming paradigm. We had previously shown that non-attentively perceived fruity odours could impact food choice intentions (on a menu card), guiding participants toward items containing more fruit and/or vegetables. The present study was designed to extend these findings, in a real-life consumption setting. One hundred and fifteen participants took part in this study, and were assigned randomly to either a control or a scented condition. On arrival in the laboratory, they were seated in a waiting room. For the scented condition, they were unobtrusively exposed to a pear odour, while under the control condition the waiting room was non-odorised. Following this waiting period, all participants moved into a non-odorised test room where they were asked to choose, from dishes served buffet-style, the starter, main course and dessert that they would actually eat for lunch. The results showed that participants subjected to the scented condition chose to consume the 'fruity' dessert (compote) more frequently than those who had waited under the control condition, who chose more frequently the dessert without fruit (brownie). In line with the findings of our previous study, these results confirm the idea of priming effects 'specific to the food cue'. To conclude, a non-attentively perceived fruity odour was shown to influence actual food choices, guiding individuals towards more fruity desserts. The involvement of implicit processes in food choices should be taken into account in guidelines and strategies designed to promote healthy eating. PMID:24462492

  10. A specific area of olfactory cortex involved in stress hormone responses to predator odours.

    PubMed

    Kondoh, Kunio; Lu, Zhonghua; Ye, Xiaolan; Olson, David P; Lowell, Bradford B; Buck, Linda B

    2016-04-01

    Instinctive reactions to danger are critical to the perpetuation of species and are observed throughout the animal kingdom. The scent of predators induces an instinctive fear response in mice that includes behavioural changes, as well as a surge in blood stress hormones that mobilizes multiple body systems to escape impending danger. How the olfactory system routes predator signals detected in the nose to achieve these effects is unknown. Here we identify a specific area of the olfactory cortex in mice that induces stress hormone responses to volatile predator odours. Using monosynaptic and polysynaptic viral tracers, we found that multiple olfactory cortical areas transmit signals to hypothalamic corticotropin-releasing hormone (CRH) neurons, which control stress hormone levels. However, only one minor cortical area, the amygdalo-piriform transition area (AmPir), contained neurons upstream of CRH neurons that were activated by volatile predator odours. Chemogenetic stimulation of AmPir activated CRH neurons and induced an increase in blood stress hormones, mimicking an instinctive fear response. Moreover, chemogenetic silencing of AmPir markedly reduced the stress hormone response to predator odours without affecting a fear behaviour. These findings suggest that AmPir, a small area comprising <5% of the olfactory cortex, plays a key part in the hormonal component of the instinctive fear response to volatile predator scents. PMID:27001694

  11. Thermogenesis, Flowering and the Association with Variation in Floral Odour Attractants in Magnolia sprengeri (Magnoliaceae)

    PubMed Central

    Wang, Ruohan; Xu, Sai; Liu, Xiangyu; Zhang, Yiyuan; Wang, Jianzhong; Zhang, Zhixiang

    2014-01-01

    Magnolia sprengeri Pamp. is an ornamentally and ecologically important tree that blooms at cold temperatures in early spring. In this study, thermogenesis and variation in the chemical compounds of floral odours and insect visitation in relation to flowering cycles were studied to increase our understanding of the role of floral thermogenesis in the pollination biology of M. sprengeri. There were five distinct floral stages across the floral cycle of this species: pre-pistillate, pistillate, pre-staminate, staminate and post-staminate. Floral thermogenesis during anthesis and consisted of two distinct peaks: one at the pistillate stage and the other at the staminate stage. Insects of five families visited M. sprengeri during the floral cycle, and sap beetles (Epuraea sp., Nitidulidae) were determined to be the most effective pollinators, whereas bees (Apis cerana, Apidae) were considered to be occasional pollinators. A strong fragrance was released during thermogenesis, consisting of 18 chemical compounds. Although the relative proportions of these compounds varied at different floral stages across anthesis, linalool, 1-iodo-2-methylundecane and 2,2,6-trimethyl-6-vinyltetrahydro-2H-pyran-3-ol were dominant. Importantly, we found that the floral blends released during the pistillate and staminate stages were very similar, and coincided with flower visitation by sap beetles and the two thermogenic episodes. Based on these results, we propose that odour acts as a signal for a reward (pollen) and that an odour mimicry of staminate-stage flowers occurs during the pistillate stage. PMID:24922537

  12. Wake up and smell the conflict: odour signals in female competition

    PubMed Central

    Stockley, Paula; Bottell, Lisa; Hurst, Jane L.

    2013-01-01

    Odour signals used in competitive and aggressive interactions between males are well studied in the context of sexual selection. By contrast, relatively little is known about comparable signals used by females, despite current interest in the evolution of female ornaments and weaponry. Available evidence suggests that odour signals are important in competitive interactions between female mammals, with reductions or reversals of male-biased sexual dimorphism in signalling where female competition is intense. Scent marking is often associated with conflict between females over access to resources or reproductive opportunities. Female scent marks may therefore provide reliable signals of competitive ability that could be used both by competitors and potential mates. Consistent with this hypothesis, we report that aggressive behaviour of female house mice is correlated with the amount of major urinary protein (MUP) excreted in their urine, a polymorphic set of proteins that are used in scent mark signalling. Under semi-natural conditions, females with high MUP output are more likely to produce offspring sired by males that have high reproductive success, and less likely to produce offspring by multiple different sires, suggesting that females with strong MUP signals are monopolized by males of particularly high quality. We conclude that odour signals are worthy of more detailed investigation as mediators of female competition. PMID:24167312

  13. Reducing variation in decomposition odour profiling using comprehensive two-dimensional gas chromatography.

    PubMed

    Perrault, Katelynn A; Stefanuto, Pierre-Hugues; Stuart, Barbara H; Rai, Tapan; Focant, Jean-François; Forbes, Shari L

    2015-01-01

    Challenges in decomposition odour profiling have led to variation in the documented odour profile by different research groups worldwide. Background subtraction and use of controls are important considerations given the variation introduced by decomposition studies conducted in different geographical environments. The collection of volatile organic compounds (VOCs) from soil beneath decomposing remains is challenging due to the high levels of inherent soil VOCs, further confounded by the use of highly sensitive instrumentation. This study presents a method that provides suitable chromatographic resolution for profiling decomposition odour in soil by comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry using appropriate controls and field blanks. Logarithmic transformation and t-testing of compounds permitted the generation of a compound list of decomposition VOCs in soil. Principal component analysis demonstrated the improved discrimination between experimental and control soil, verifying the value of the data handling method. Data handling procedures have not been well documented in this field and standardisation would thereby reduce misidentification of VOCs present in the surrounding environment as decomposition byproducts. Uniformity of data handling and instrumental procedures will reduce analytical variation, increasing confidence in the future when investigating the effect of taphonomic variables on the decomposition VOC profile.

  14. A specific area of olfactory cortex involved in stress hormone responses to predator odours.

    PubMed

    Kondoh, Kunio; Lu, Zhonghua; Ye, Xiaolan; Olson, David P; Lowell, Bradford B; Buck, Linda B

    2016-04-01

    Instinctive reactions to danger are critical to the perpetuation of species and are observed throughout the animal kingdom. The scent of predators induces an instinctive fear response in mice that includes behavioural changes, as well as a surge in blood stress hormones that mobilizes multiple body systems to escape impending danger. How the olfactory system routes predator signals detected in the nose to achieve these effects is unknown. Here we identify a specific area of the olfactory cortex in mice that induces stress hormone responses to volatile predator odours. Using monosynaptic and polysynaptic viral tracers, we found that multiple olfactory cortical areas transmit signals to hypothalamic corticotropin-releasing hormone (CRH) neurons, which control stress hormone levels. However, only one minor cortical area, the amygdalo-piriform transition area (AmPir), contained neurons upstream of CRH neurons that were activated by volatile predator odours. Chemogenetic stimulation of AmPir activated CRH neurons and induced an increase in blood stress hormones, mimicking an instinctive fear response. Moreover, chemogenetic silencing of AmPir markedly reduced the stress hormone response to predator odours without affecting a fear behaviour. These findings suggest that AmPir, a small area comprising <5% of the olfactory cortex, plays a key part in the hormonal component of the instinctive fear response to volatile predator scents.

  15. Anxiolytic effects of Lavandula angustifolia odour on the Mongolian gerbil elevated plus maze.

    PubMed

    Bradley, B F; Starkey, N J; Brown, S L; Lea, R W

    2007-05-22

    Lavender is a popular treatment for stress and mild anxiety in Europe and the USA. The present study investigated the effects of (Lavandula angustifolia Mill. (Lamiaceae)) lavender odour inhalation over 2 weeks or 24 h periods, on gerbil behaviour in the elevated plus maze in mature male and female gerbils, and compared results with the effects of diazepam (1 mg/kg) i.p. after 30 min and 2-week administration. Traditional measures of open entries showed an increasing trend over the 2 weeks exposure, whereas ethological measures indicative of anxiety; stretch-attend frequency and percentage protected head-dips, were significantly lower. Exploratory behaviour, total head-dip frequency, increased after 24 h lavender and 2 weeks exposure. These results are comparable with diazepam administration. There were sex differences in protected head-dip an ethological indicator of anxiety: females showed a significant decrease in protected head-dips compared to both males and to female controls. In conclusion exposure to lavender odour may have an anxiolytic profile in gerbils similar to that of the anxiolytic diazepam. In addition, prolonged, 2-week lavender odour exposure increased exploratory behaviour in females indicating a further decrease in anxiety in this sex.

  16. Major histocompatibility complex peptide ligands as olfactory cues in human body odour assessment.

    PubMed

    Milinski, Manfred; Croy, Ilona; Hummel, Thomas; Boehm, Thomas

    2013-03-22

    In many animal species, social communication and mate choice are influenced by cues encoded by the major histocompatibility complex (MHC). The mechanism by which the MHC influences sexual selection is a matter of intense debate. In mice, peptide ligands of MHC molecules activate subsets of vomeronasal and olfactory sensory neurons and influence social memory formation; in sticklebacks, such peptides predictably modify the outcome of mate choice. Here, we examine whether this evolutionarily conserved mechanism of interindividual communication extends to humans. In psychometric tests, volunteers recognized the supplementation of their body odour by MHC peptides and preferred 'self' to 'non-self' ligands when asked to decide whether the modified odour smelled 'like themselves' or 'like their favourite perfume'. Functional magnetic resonance imaging indicated that 'self'-peptides specifically activated a region in the right middle frontal cortex. Our results suggest that despite the absence of a vomeronasal organ, humans have the ability to detect and evaluate MHC peptides in body odour. This may provide a basis for the sensory evaluation of potential partners during human mate choice.

  17. Activation, orientation and landing of female Culex quinquefasciatus in response to carbon dioxide and odour from human feet: 3-D flight analysis in a wind tunnel.

    PubMed

    Lacey, E S; Cardé, R T

    2011-03-01

    This study investigated the interaction between carbon dioxide (CO(2) ) and human foot odour on activation, upwind orientation and landing of host-seeking female Culex quinquefasciatus (Say) (Diptera: Culicidae) in a wind tunnel. More mosquitoes landed on warmed glass beads coated with foot odour than on clean beads; adding a plume of 4% CO(2) did not influence the proportion of mosquitoes landing. A second experiment used 3-dimensional video tracking to assess flight performance. Activation was more rapid with CO(2) and with CO(2) + foot odour than with clean air or with foot odour alone. Upwind flights were fastest with CO(2) and with clean air, and slowest with foot odour; the CO(2) + foot odour treatment overlapped the previous three treatments in significance. Flight headings tended more towards due upwind with CO(2) and with clean air than with CO(2) + foot odour or with foot odour alone. In both experiments, many mosquitoes flew upwind in clean air. There was little evidence of females changing course upon entering or exiting the CO(2) plume or reacting to foot odour during flight.

  18. Preliminary lack of evidence for simian odour preferences of savanna populations of Anopheles gambiae and other malaria vectors.

    PubMed

    Costantini, C; Diallo, M

    2001-12-01

    The behavioural response to several culicine and anopheline mosquitoes to the odour of alternative hosts (human vs monkey) arranged in a choice set-up using odour-baited entry traps (OBETs) was assessed in a field experiment in south-eastern Senegal. The experimental protocol followed procedures analogous to those adopted in olfactometer laboratory tests. Two adult Cercopithecus aethiops and a child of similar mass slept inside separate tents and their odours were drawn to each one of two paired OBETs so that approaching mosquitoes could experience both odour-laden streams before "choosing" to fly against one of the two air currents and into the trap. The traps were set up in a riverine forest clearing near the town of Kedougou, where primates (Papio papio, Cercopithecus aethiops, and Erythrocebus patas) are common. A total of 192 mosquitoes belonging to 4 genera was captured during 8 trap nights. All major human malaria vectors including Anopheles gambiae sensu lato, An. funestus, and An. nili, which constituted the bulk of the trap catch (N = 153), clearly expressed a preference for human odour, with > 90% of captured mosquitoes caught in the human-baited trap. A sub-sample of specimens belonging to the An. gambiae complex caught in both traps was identified by rDNA-PCR and RFLP as An. gambiae sensu stricto molecular form S (7/10), and An. arabiensis (3/10). The only species that did not show a preference for the alternative odour-laden air streams, among those caught in significant numbers, were mosquitoes of the genus Mansonia, with both Ma. uniformis and Ma. africana weakly preferring human odour, but not at a statistically significant level. These results are in accordance with the hypothesis that the strongly anthropophilic feeding preferences of An. gambiae did not evolve from an ancestral association with non-human primates.

  19. Developing Recognition Programs for Units within Student Affairs.

    ERIC Educational Resources Information Center

    Avery, Cynthia M.

    2001-01-01

    According to many psychologists, the connections between motivation and rewards and recognition are crucial to employee satisfaction. A plan for developing a multi-layered recognition program within a division of student affairs is described. These recognitions programs are designed taking into account the differences in perceptions of awards by…

  20. Predator Recognition in Rainbowfish, Melanotaenia duboulayi, Embryos

    PubMed Central

    Oulton, Lois Jane; Haviland, Vivian; Brown, Culum

    2013-01-01

    Exposure to olfactory cues during embryonic development can have long term impacts on birds and amphibians behaviour. Despite the vast literature on predator recognition and responses in fishes, few researchers have determined how fish embryos respond to predator cues. Here we exposed four-day-old rainbowfish (Melanotaenia duboulayi) embryos to cues emanating from a novel predator, a native predator and injured conspecifics. Their response was assessed by monitoring heart rate and hatch time. Results showed that embryos have an innate capacity to differentiate between cues as illustrated by faster heart rates relative to controls. The greatest increase in heart rate occurred in response to native predator odour. While we found no significant change in the time taken for eggs to hatch, all treatments experienced slight delays as expected if embryos are attempting to reduce exposure to larval predators. PMID:24146817

  1. Prospects for the Development of Odour Baits to Control the Tsetse Flies Glossina tachinoides and G. palpalis s.l.

    PubMed Central

    Rayaisse, J. B.; Tirados, I.; Kaba, D.; Dewhirst, S. Y.; Logan, J. G.; Diarrassouba, A.; Salou, E.; Omolo, M. O.; Solano, P.; Lehane, M. J.; Pickett, J. A.; Vale, G. A.; Torr, S. J.; Esterhuizen, J.

    2010-01-01

    Field studies were done of the responses of Glossina palpalis palpalis in Côte d'Ivoire, and G. p. gambiensis and G. tachinoides in Burkina Faso, to odours from humans, cattle and pigs. Responses were measured either by baiting (1.) biconical traps or (2.) electrocuting black targets with natural host odours. The catch of G. tachinoides from traps was significantly enhanced (∼5×) by odour from cattle but not humans. In contrast, catches from electric targets showed inconsistent results. For G. p. gambiensis both human and cattle odour increased (>2×) the trap catch significantly but not the catch from electric targets. For G. p. palpalis, odours from pigs and humans increased (∼5×) the numbers of tsetse attracted to the vicinity of the odour source but had little effect on landing or trap-entry. For G. tachinoides a blend of POCA (P = 3-n-propylphenol; O = 1-octen-3-ol; C = 4-methylphenol; A = acetone) alone or synthetic cattle odour (acetone, 1-octen-3-ol, 4-methylphenol and 3-n-propylphenol with carbon dioxide) consistently caught more tsetse than natural cattle odour. For G. p. gambiensis, POCA consistently increased catches from both traps and targets. For G. p. palpalis, doses of carbon dioxide similar to those produced by a host resulted in similar increases in attraction. Baiting traps with super-normal (∼500 mg/h) doses of acetone also consistently produced significant but slight (∼1.6×) increases in catches of male flies. The results suggest that odour-baited traps and insecticide-treated targets could assist the AU-Pan African Tsetse and Trypanosomiasis Eradication Campaign (PATTEC) in its current efforts to monitor and control Palpalis group tsetse in West Africa. For all three species, only ∼50% of the flies attracted to the vicinity of the trap were actually caught by it, suggesting that better traps might be developed by an analysis of the visual responses and identification of any semiochemicals involved in short

  2. Volatile trace compounds released from municipal solid waste at the transfer stage: Evaluation of environmental impacts and odour pollution.

    PubMed

    Zhao, Yan; Lu, Wenjing; Wang, Hongtao

    2015-12-30

    Odour pollution caused by municipal solid waste is a public concern. This study quantitatively evaluated the concentration, environmental impacts, and olfaction of volatile trace compounds released from a waste transfer station. Seventy-six compounds were detected, and ethanol presented the highest releasing rate and ratio of 14.76 kg/d and 12.30 g/t of waste, respectively. Life cycle assessment showed that trichlorofluoromethane and dichlorodifluoromethane accounted for more than 99% of impact potentials to global warming and approximately 70% to human toxicity (non-carcinogenic). The major contributor for both photochemical ozone formation and ecotoxicity was ethanol. A detection threshold method was also used to evaluate odour pollution. Five compounds including methane thiol, hydrogen sulphide, ethanol, dimethyl disulphide, and dimethyl sulphide, with dilution multiples above one, were considered the critical compounds. Methane thiol showed the highest contribution to odour pollution of more than 90%, as indicated by its low threshold. Comparison of the contributions of the compounds to different environmental aspects indicated that typical pollutants varied based on specific evaluation targets and therefore should be comprehensively considered. This study provides important information and scientific methodology to elucidate the impacts of odourant compounds to the environment and odour pollution.

  3. Odour representation in honeybee olfactory glomeruli shows slow temporal dynamics: an optical recording study using a voltage-sensitive dye.

    PubMed

    Galizia; Küttner; Joerges; Menzel

    2000-06-01

    Stimulation with odours has been shown to elicit characteristic patterns of activated glomeruli in the antennal lobe (AL) of honeybees. In this study we show that these patterns are dynamic in a time window of 2-3 s after stimulus onset. We measured changes in the averaged membrane potential of all cells in the glomerular neuropil by optical imaging of the voltage-sensitive dye RH795 using a slow scan CCD camera (3 frames/s). The four substances 1-hexanol, hexanal, citral and clove-oil as well as the binary mixtures hexanol+hexanal and hexanol+citral were used as stimuli (2 s stimulus duration). We found that: (1) every odour elicited an odour-specific activity pattern, and conversely every glomerulus had a characteristic odour response profile; (2) some glomeruli had a tonic, some a phasic-tonic, and some a slow phasic response pattern; (3) the difference between the glomerular response patterns increased within 2 s of stimulus presentation, which suggests that odour representations became more characteristic over stimulus time; and (4) the responses to odorant mixtures were complex and glomerulus-dependent: some responses correspond to the sum of the compounds' responses, some to the response of one of the components.

  4. Control of odour nuisance in urban areas: the efficiency and social acceptance of the application of masking agents.

    PubMed

    Lazarova, Valentina; Abed, Brahim; Markovska, Gabriela; Dezenclos, Thierry; Amara, Aït

    2013-01-01

    This paper presents and discusses the results of the project named 'Jasmin' implemented in Algiers to control the strong odours of the river named Oued El Harrach, one of the largest rivers in the centre of the city. Pending the achievement of curative solutions, a temporary option for mitigation of nuisance odour by masking agents was implemented in the vicinity of the main bridges. The efficiency of this technology has been followed by means of an odour panel with the participation of representatives of all stakeholders. A sociological study by means of 1,000 questionnaires and face-to-face interviews of the local population demonstrated the benefits and the positive outcomes of the attenuation of odour nuisance: 70% of the surveyed population is satisfied or very satisfied with the application of masking agents and 96% of respondents support the continuation of the project. In terms of size and public access, the project Jasmin is a world-first demonstration of odour control in urban areas in developing countries.

  5. Odour-tracking capability of a silkmoth driving a mobile robot with turning bias and time delay.

    PubMed

    Ando, N; Emoto, S; Kanzaki, R

    2013-03-01

    The reconstruction of mechanisms behind odour-tracking behaviours of animals is expected to enable the development of biomimetic robots capable of adaptive behaviour and effectively locating odour sources. However, because the behavioural mechanisms of animals have not been extensively studied, their behavioural capabilities cannot be verified. In this study, we have employed a mobile robot driven by a genuine insect (insect-controlled robot) to evaluate the behavioural capabilities of a biological system implemented in an artificial system. We used a male silkmoth as the 'driver' and investigated its behavioural capabilities to imposed perturbations during odour tracking. When we manipulated the robot to induce the turning bias, it located the odour source by compensatory turning of the on-board moth. Shifting of the orientation paths to the odour plume boundaries and decreased orientation ability caused by covering the visual field suggested that the moth steered with bilateral olfaction and vision to overcome the bias. An evaluation of the time delays of the moth and robot movements suggested an acceptable range for sensory-motor processing when the insect system was directly applied to artificial systems. Further evaluations of the insect-controlled robot will provide a 'blueprint' for biomimetic robots and strongly promote the field of biomimetics. PMID:23385386

  6. Volatile trace compounds released from municipal solid waste at the transfer stage: Evaluation of environmental impacts and odour pollution.

    PubMed

    Zhao, Yan; Lu, Wenjing; Wang, Hongtao

    2015-12-30

    Odour pollution caused by municipal solid waste is a public concern. This study quantitatively evaluated the concentration, environmental impacts, and olfaction of volatile trace compounds released from a waste transfer station. Seventy-six compounds were detected, and ethanol presented the highest releasing rate and ratio of 14.76 kg/d and 12.30 g/t of waste, respectively. Life cycle assessment showed that trichlorofluoromethane and dichlorodifluoromethane accounted for more than 99% of impact potentials to global warming and approximately 70% to human toxicity (non-carcinogenic). The major contributor for both photochemical ozone formation and ecotoxicity was ethanol. A detection threshold method was also used to evaluate odour pollution. Five compounds including methane thiol, hydrogen sulphide, ethanol, dimethyl disulphide, and dimethyl sulphide, with dilution multiples above one, were considered the critical compounds. Methane thiol showed the highest contribution to odour pollution of more than 90%, as indicated by its low threshold. Comparison of the contributions of the compounds to different environmental aspects indicated that typical pollutants varied based on specific evaluation targets and therefore should be comprehensively considered. This study provides important information and scientific methodology to elucidate the impacts of odourant compounds to the environment and odour pollution. PMID:26292056

  7. Differential attractiveness of human foot odours to Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) and variation in their chemical composition.

    PubMed

    Omolo, M O; Njiru, B; Ndiege, I O; Musau, R M; Hassanali, A

    2013-10-01

    Counter flow geometry (CFG) traps (American Biophysics) baited with foot odours (adsorbed overnight on a combination of a nylon and a cotton socks) from 4 groups of 4 male volunteers were initially used in a screen-house to compare and grade the attractiveness of Anopheles gambiae Giles sensu stricto to these odours. Ten individuals were then selected from the 4 groups for further grading in which mosquito attractiveness to odours adsorbed on socks worn by each of the individuals was compared against a control (clean, un-worn cotton and nylon socks). A gradation of attractiveness was found, with the most attractive foot odour catching 8-fold more mosquitoes than the least attractive one (t-test, p=0.001). For comparison of the chromatographic profiles of the foot odours and identification of their constituents, six adsorbents (tenax, chromsorb, porapak Q, activated charcoal, reverse phase octadecyl and octyl bonded silica) were evaluated for their suitability in trapping the volatiles in a static mode. Of these, porapak Q was found to be the most effective. Comparison of the gas-chromatographic (GC) and gas chromatography-linked mass spectrometry (GC-MS) profiles of blends collected from the most and least attractive feet on porapak Q adsorbent revealed both qualitative and quantitative differences. The implication of our finding on differential attraction of An. gambiae to their preferred feeding site of different human subjects is highlighted.

  8. Odour-tracking capability of a silkmoth driving a mobile robot with turning bias and time delay.

    PubMed

    Ando, N; Emoto, S; Kanzaki, R

    2013-03-01

    The reconstruction of mechanisms behind odour-tracking behaviours of animals is expected to enable the development of biomimetic robots capable of adaptive behaviour and effectively locating odour sources. However, because the behavioural mechanisms of animals have not been extensively studied, their behavioural capabilities cannot be verified. In this study, we have employed a mobile robot driven by a genuine insect (insect-controlled robot) to evaluate the behavioural capabilities of a biological system implemented in an artificial system. We used a male silkmoth as the 'driver' and investigated its behavioural capabilities to imposed perturbations during odour tracking. When we manipulated the robot to induce the turning bias, it located the odour source by compensatory turning of the on-board moth. Shifting of the orientation paths to the odour plume boundaries and decreased orientation ability caused by covering the visual field suggested that the moth steered with bilateral olfaction and vision to overcome the bias. An evaluation of the time delays of the moth and robot movements suggested an acceptable range for sensory-motor processing when the insect system was directly applied to artificial systems. Further evaluations of the insect-controlled robot will provide a 'blueprint' for biomimetic robots and strongly promote the field of biomimetics.

  9. An olfactory receptor for food-derived odours promotes male courtship in Drosophila.

    PubMed

    Grosjean, Yael; Rytz, Raphael; Farine, Jean-Pierre; Abuin, Liliane; Cortot, Jérôme; Jefferis, Gregory S X E; Benton, Richard

    2011-10-13

    Many animals attract mating partners through the release of volatile sex pheromones, which can convey information on the species, gender and receptivity of the sender to induce innate courtship and mating behaviours by the receiver. Male Drosophila melanogaster fruitflies display stereotyped reproductive behaviours towards females, and these behaviours are controlled by the neural circuitry expressing male-specific isoforms of the transcription factor Fruitless (FRU(M)). However, the volatile pheromone ligands, receptors and olfactory sensory neurons (OSNs) that promote male courtship have not been identified in this important model organism. Here we describe a novel courtship function of Ionotropic receptor 84a (IR84a), which is a member of the chemosensory ionotropic glutamate receptor family, in a previously uncharacterized population of FRU(M)-positive OSNs. IR84a-expressing neurons are activated not by fly-derived chemicals but by the aromatic odours phenylacetic acid and phenylacetaldehyde, which are widely found in fruit and other plant tissues that serve as food sources and oviposition sites for drosophilid flies. Mutation of Ir84a abolishes both odour-evoked and spontaneous electrophysiological activity in these neurons and markedly reduces male courtship behaviour. Conversely, male courtship is increased--in an IR84a-dependent manner--in the presence of phenylacetic acid but not in the presence of another fruit odour that does not activate IR84a. Interneurons downstream of IR84a-expressing OSNs innervate a pheromone-processing centre in the brain. Whereas IR84a orthologues and phenylacetic-acid-responsive neurons are present in diverse drosophilid species, IR84a is absent from insects that rely on long-range sex pheromones. Our results suggest a model in which IR84a couples food presence to the activation of the fru(M) courtship circuitry in fruitflies. These findings reveal an unusual but effective evolutionary solution to coordinate feeding and

  10. A rapid chemical odour profiling method for the identification of rhinoceros horns.

    PubMed

    Ueland, Maiken; Ewart, Kyle; Troobnikoff, Amanda N; Frankham, Greta; Johnson, Rebecca N; Forbes, Shari L

    2016-09-01

    Illegal poaching causes great harm to species diversity and conservation. A vast amount of money is involved in the trade of illegal or forged animal parts worldwide. In many cases, the suspected animal part is unidentifiable and requires costly and invasive laboratory analysis such as isotopic fingerprinting or DNA testing. The lack of rapid and accurate methods to identify wildlife parts at the point of detection represents a major hindrance in the enforcement and prosecution of wildlife trafficking. The ability of wildlife detector dogs to alert to different wildlife species demonstrates that there is a detectable difference in scent profile of illegally traded animal parts. This difference was exploited to develop a rapid, non-invasive screening method for distinguishing rhinoceros horns of different species. The method involved the collection of volatile organic compounds (VOC) by headspace solid-phase microextraction (HS-SPME) and analysis by comprehensive two-dimensional gas chromatography - time-of-flight mass spectrometry (GC×GC-TOFMS). It was hypothesised that the use of the specific odour profile as a screening method could separate and differentiate geographic origin or exploit the difference in diets of different species within a family (such as white rhinoceros and black rhinoceros from the Rhinocerotidae family). Known black and white rhinoceros horn samples were analysed using HS-SPME-GC×GC-TOFMS and multivariate statistics were applied to identify groupings in the data set. The black rhinoceros horn samples were distinctly different from the white rhinoceros horn samples. This demonstrated that seized rhinoceros horn samples can be identified based on their distinct odour profiles. The chemical odour profiling method has great potential as a rapid and non-invasive screening method in order to combat and track illegal trafficking of wildlife parts.

  11. Technological and life cycle assessment of organics processing odour control technologies.

    PubMed

    Bindra, Navin; Dubey, Brajesh; Dutta, Animesh

    2015-09-15

    As more municipalities and communities across developed world look towards implementing organic waste management programmes or upgrading existing ones, composting facilities are emerging as a popular choice. However, odour from these facilities continues to be one of the most important concerns in terms of cost & effective mitigation. This paper provides a technological and life cycle assessment of some of the different odour control technologies and treatment methods that can be implemented in organics processing facilities. The technological assessment compared biofilters, packed tower wet scrubbers, fine mist wet scrubbers, activated carbon adsorption, thermal oxidization, oxidization chemicals and masking agents. The technologies/treatment methods were evaluated and compared based on a variety of operational, usage and cost parameters. Based on the technological assessment it was found that, biofilters and packed bed wet scrubbers are the most applicable odour control technologies for use in organics processing faculties. A life cycle assessment was then done to compare the environmental impacts of the packed-bed wet scrubber system, organic (wood-chip media) bio-filter and inorganic (synthetic media) bio-filter systems. Twelve impact categories were assessed; cumulative energy demand (CED), climate change, human toxicity, photochemical oxidant formation, metal depletion, fossil depletion, terrestrial acidification, freshwater eutrophication, marine eutrophication, terrestrial eco-toxicity, freshwater eco-toxicity and marine eco-toxicity. The results showed that for all impact categories the synthetic media biofilter had the highest environmental impact, followed by the wood chip media bio-filter system. The packed-bed system had the lowest environmental impact for all categories.

  12. A rapid chemical odour profiling method for the identification of rhinoceros horns.

    PubMed

    Ueland, Maiken; Ewart, Kyle; Troobnikoff, Amanda N; Frankham, Greta; Johnson, Rebecca N; Forbes, Shari L

    2016-09-01

    Illegal poaching causes great harm to species diversity and conservation. A vast amount of money is involved in the trade of illegal or forged animal parts worldwide. In many cases, the suspected animal part is unidentifiable and requires costly and invasive laboratory analysis such as isotopic fingerprinting or DNA testing. The lack of rapid and accurate methods to identify wildlife parts at the point of detection represents a major hindrance in the enforcement and prosecution of wildlife trafficking. The ability of wildlife detector dogs to alert to different wildlife species demonstrates that there is a detectable difference in scent profile of illegally traded animal parts. This difference was exploited to develop a rapid, non-invasive screening method for distinguishing rhinoceros horns of different species. The method involved the collection of volatile organic compounds (VOC) by headspace solid-phase microextraction (HS-SPME) and analysis by comprehensive two-dimensional gas chromatography - time-of-flight mass spectrometry (GC×GC-TOFMS). It was hypothesised that the use of the specific odour profile as a screening method could separate and differentiate geographic origin or exploit the difference in diets of different species within a family (such as white rhinoceros and black rhinoceros from the Rhinocerotidae family). Known black and white rhinoceros horn samples were analysed using HS-SPME-GC×GC-TOFMS and multivariate statistics were applied to identify groupings in the data set. The black rhinoceros horn samples were distinctly different from the white rhinoceros horn samples. This demonstrated that seized rhinoceros horn samples can be identified based on their distinct odour profiles. The chemical odour profiling method has great potential as a rapid and non-invasive screening method in order to combat and track illegal trafficking of wildlife parts. PMID:27240958

  13. Nest-mate recognition template of guard honeybees (Apis mellifera) is modified by wax comb transfer.

    PubMed

    Couvillon, Margaret J; Caple, Jamie P; Endsor, Samuel L; Kärcher, Martin; Russell, Trudy E; Storey, Darren E; Ratnieks, Francis L W

    2007-06-22

    In recognition, discriminators use sensory information to make decisions. For example, honeybee (Apis mellifera) entrance guards discriminate between nest-mates and intruders by comparing their odours with a template of the colony odour. Comb wax plays a major role in honeybee recognition. We measured the rejection rates of nest-mate and non-nest-mate worker bees by entrance guards before and after a unidirectional transfer of wax comb from a 'comb donor' hive to a 'comb receiver' hive. Our results showed a significant effect that occurred in one direction. Guards in the comb receiver hive became more accepting of non-nest-mates from the comb donor hive (rejection decreased from 70 to 47%); however, guards in the comb donor hive did not become more accepting of bees from the comb receiver hive. These data strongly support the hypothesis that the transfer of wax comb increases the acceptance of non-nest-mates not by changing the odour of the bees, but by changing the template used by guards.

  14. Cross-modality effects of prey odour during the intraspecific interactions of a mosquito-specialist predator

    PubMed Central

    Cross, Fiona R.; Jackson, Robert R.

    2014-01-01

    One of the predictions from evolutionary game theory is that individuals will increase their willingness (i.e., become primed) to escalate aggression when they detect the presence of a limiting resource. Here we test this prediction in the context of prey odour priming escalation decisions during vision-based encounters by Evarcha culicivora. This East African jumping spider (Salticidae) feeds indirectly on vertebrate blood by actively choosing blood-carrying female mosquitoes as preferred prey. Unlike many salticid species, it also expresses pronounced mutual mate choice. As predicted, we show here that, in the presence of odour from their preferred prey, both sexes of E. culicivora escalate during vision-based same-sex encounters. This is further evidence that the odour of blood-carrying mosquitoes is salient to this salticid. For both sexes of E. culicivora, this particular prey may be a resource that matters in the context of intrasexual selection. PMID:24839338

  15. Comparison of heating methods and the use of different tissues for sensory assessment of abnormal odours (boar taint) in pig meat.

    PubMed

    Whittington, F M; Zammerini, D; Nute, G R; Baker, A; Hughes, S I; Wood, J D

    2011-06-01

    Five heating methods (microwave, hotwire, boiling at 25 °C and 75 °C and melting) were used to generate cooking odours from backfat of entire male pigs and a 'composite' sample consisting of fat and muscle from the head along with salivary glands. The methods elicited significantly different scores for odours from 4 groups of 10 samples differing in their concentrations and ratios of skatole and androstenone. The odours (pork odour, abnormal odour, skatole odour and androstenone odour) were assessed by 3 experienced assessors. Correlations between skatole and androstenone concentrations and abnormal odour score in backfat were higher for skatole, suggesting it is the more important boar taint compound. In the composite sample, androstenone concentration was much higher than in backfat and androstenone was a more important contributor to boar taint. The microwave, hotwire and boiling (75 °C) methods produced the clearest separation between samples and the microwave method was considered the most suitable for on-line use.

  16. Scent of a Dragonfly: Sex Recognition in a Polymorphic Coenagrionid

    PubMed Central

    Conti, Eric; Rebora, Manuela; Salerno, Gianandrea

    2015-01-01

    In polymorphic damselflies discrimination of females from males is complex owing to the presence of androchrome and gynochrome females. To date there is no evidence that damselflies use sensory modalities other than vision (and tactile stimuli) in mate searching and sex recognition. The results of the present behavioural and electrophysiological investigations on Ischnura elegans, a polymorphic damselfly, support our hypothesis that chemical cues could be involved in Odonata sex recognition. The bioassays demonstrate that males in laboratory prefer female to male odour, while no significant difference was present in male behavior between stimuli from males and control. The bioassays suggest also some ability of males to distinguish between the two female morphs using chemical stimuli. The ability of male antennae to perceive odours from females has been confirmed by electrophysiological recordings. These findings are important not only to get insight into the chemical ecology of Odonata, and to shed light into the problem of olfaction in Paleoptera, but could be useful to clarify the controversial aspects of the mating behavior of polymorphic coenagrionids. Behavioural studies in the field are necessary to investigate further these aspects. PMID:26305118

  17. Scent of a Dragonfly: Sex Recognition in a Polymorphic Coenagrionid.

    PubMed

    Frati, Francesca; Piersanti, Silvana; Conti, Eric; Rebora, Manuela; Salerno, Gianandrea

    2015-01-01

    In polymorphic damselflies discrimination of females from males is complex owing to the presence of androchrome and gynochrome females. To date there is no evidence that damselflies use sensory modalities other than vision (and tactile stimuli) in mate searching and sex recognition. The results of the present behavioural and electrophysiological investigations on Ischnura elegans, a polymorphic damselfly, support our hypothesis that chemical cues could be involved in Odonata sex recognition. The bioassays demonstrate that males in laboratory prefer female to male odour, while no significant difference was present in male behavior between stimuli from males and control. The bioassays suggest also some ability of males to distinguish between the two female morphs using chemical stimuli. The ability of male antennae to perceive odours from females has been confirmed by electrophysiological recordings. These findings are important not only to get insight into the chemical ecology of Odonata, and to shed light into the problem of olfaction in Paleoptera, but could be useful to clarify the controversial aspects of the mating behavior of polymorphic coenagrionids. Behavioural studies in the field are necessary to investigate further these aspects. PMID:26305118

  18. Evaluating odour control technologies using reliability and sustainability criteria--a case study for water treatment plants.

    PubMed

    Kraakman, N J R; Estrada, J M; Lebrero, R; Cesca, J; Muñoz, R

    2014-01-01

    Technologies for odour control have been widely reviewed and their optimal range of application and performance has been clearly established. Selection criteria, mainly driven by process economics, are usually based on the air flow volume, the inlet concentrations and the required removal efficiency. However, these criteria are shifting with social and environmental issues becoming as important as process economics. A methodology is illustrated to quantify sustainability and robustness of odour control technology in the context of odour control at wastewater treatment or water recycling plants. The most commonly used odour abatement techniques (biofiltration, biotrickling filtration, activated carbon adsorption, chemical scrubbing, activated sludge diffusion and biotrickling filtration coupled with activated carbon adsorption) are evaluated in terms of: (1) sustainability, with quantification of process economics, environmental performance and social impact using the sustainability metrics of the Institution of Chemical Engineers; (2) sensitivity towards design and operating parameters like utility prices (energy and labour), inlet odour concentration (H2S) and design safety (gas contact time); (3) robustness, quantifications of operating reliability, with recommendations to improve reliability during their lifespan of operations. The results show that the odour treatment technologies with the highest investments presented the lowest operating costs, which means that the net present value (NPV) should be used as a selection criterion rather than investment costs. Economies of scale are more important in biotechniques (biofiltration and biotrickling filtration) as, at increased airflows, their reduction in overall costs over 20 years (NPV20) is more extreme when compared to the physical/chemical technologies (chemical scrubbing and activated carbon filtration). Due to their low NPV and their low environmental impact, activated sludge diffusion and biotrickling

  19. Evaluating odour control technologies using reliability and sustainability criteria--a case study for water treatment plants.

    PubMed

    Kraakman, N J R; Estrada, J M; Lebrero, R; Cesca, J; Muñoz, R

    2014-01-01

    Technologies for odour control have been widely reviewed and their optimal range of application and performance has been clearly established. Selection criteria, mainly driven by process economics, are usually based on the air flow volume, the inlet concentrations and the required removal efficiency. However, these criteria are shifting with social and environmental issues becoming as important as process economics. A methodology is illustrated to quantify sustainability and robustness of odour control technology in the context of odour control at wastewater treatment or water recycling plants. The most commonly used odour abatement techniques (biofiltration, biotrickling filtration, activated carbon adsorption, chemical scrubbing, activated sludge diffusion and biotrickling filtration coupled with activated carbon adsorption) are evaluated in terms of: (1) sustainability, with quantification of process economics, environmental performance and social impact using the sustainability metrics of the Institution of Chemical Engineers; (2) sensitivity towards design and operating parameters like utility prices (energy and labour), inlet odour concentration (H2S) and design safety (gas contact time); (3) robustness, quantifications of operating reliability, with recommendations to improve reliability during their lifespan of operations. The results show that the odour treatment technologies with the highest investments presented the lowest operating costs, which means that the net present value (NPV) should be used as a selection criterion rather than investment costs. Economies of scale are more important in biotechniques (biofiltration and biotrickling filtration) as, at increased airflows, their reduction in overall costs over 20 years (NPV20) is more extreme when compared to the physical/chemical technologies (chemical scrubbing and activated carbon filtration). Due to their low NPV and their low environmental impact, activated sludge diffusion and biotrickling

  20. Examining the development of individual recognition in a burrow-nesting procellariiform, the Leach's storm-petrel.

    PubMed

    O'Dwyer, Terence W; Ackerman, A L; Nevitt, Gabrielle A

    2008-02-01

    Burrow-nesting petrels use their well-developed sense of smell for foraging, homing to their nest, and mate recognition. The chicks of burrow-nesting petrels can apparently learn odours associated with prey while still in the nest, but the development of individual-specific odour recognition is less well understood. We used a simple two-choice test to determine whether 4- to 6-week-old chicks of a small, burrow-nesting species, the Leach's storm-petrel (Oceanodroma leucorhoa), prefer the scent of their own nest material to (1) the scent of similar organic material collected from the colony or (2) the scent of a conspecific's nest material. Results suggest that chicks clearly preferred the scent of their own nest material to that of similar organic material collected from the colony (96%; N=24; binomial test, P<0.001). Results further suggested that birds preferred the scent of their own nest material to that of a conspecific, though the preference was statistically less robust (67%; N=39; binomial test, P=0.05). Because Leach's storm-petrel chicks do not normally leave their burrow prior to fledging, an ability to recognise individual or nest-specific odours is not likely to be used for homing but instead may be linked to the development of individual recognition in different contexts. PMID:18203988

  1. Elimination of sulphur odours at landfills by bioconversion and the corona discharge plasma technique.

    PubMed

    Xia, Fangfang; Liu, Xin; Kang, Ying; He, Ruo; Wu, Zucheng

    2015-01-01

    Hydrogen sulphide (H2S) contributes a lot to odours at landfills, which is a threat to the environment and the health of the staff therein. To mitigate its emission, the bioconversion within landfill cover soils (LCSs) was introduced. H2S emission and concentration both in the field air above the landfill and in microcosm testing were surveyed. Results indicated that H2S emission and concentration in the landfill varied with landfill seasons and sites. There existed relationship between H2S concentration and fluxes spatially and temporally. To characterize and assess the spatial and temporal diversity of sulphur-oxidizing bacteria (SOB) and sulphate-reducing bacteria (SRB) in the LCSs, the terminal-restriction fragment length polymorphism technique was employed. Using the functional genes of dsrB and soxB, SOB, including Halothiobacillus, Rhodothalassium, Paracocccus, Allochromatium, and Thiobacillus, and SRB, including Desulfovibrio, Syntrophobacter, Desulfomonile and Desulfobacca, were identical and exhibited the dominant role in the LCSs. By employing an alternative available corona reactor, more than 90% removal efficiencies of sulphides were demonstrated, suggesting that the LCSs for eliminating odours in a lower concentration would be feasible.

  2. African penguins (Spheniscus demersus) can detect dimethyl sulphide, a prey-related odour.

    PubMed

    Cunningham, Gregory B; Strauss, Venessa; Ryan, Peter G

    2008-10-01

    Although it is well established that certain procellariiform seabirds use odour cues to find prey, it is not clear whether penguins use olfactory cues to forage. It is commonly assumed that penguins lack a sense of smell, yet they are closely related to procellariiforms and forage on similar types of prey in similar areas to many procellariiforms. Such regions are characterized by having high levels of dimethyl sulphide (DMS) a scented compound that many marine animals use to locate foraging grounds. If penguins can smell, DMS may be a biologically relevant scented compound that they may be sensitive to in nature. To test this hypothesis, we investigated whether adult African penguins (Spheniscus demersus) could detect DMS using two separate experiments. We tested wild penguins on Robben Island, South Africa, by deploying mumolar DMS solutions in the colonies, and found that birds slowed down their walking speeds. We also tested captive penguins in a Y-maze. In both cases, our data convincingly demonstrate that African penguins have a functioning sense of smell and are attracted to DMS. The implication of this work is that the detection of changes in the odour landscape (DMS) may assist penguins in identifying productive areas of the ocean for foraging. At-sea studies are needed to investigate this issue further. PMID:18805811

  3. Performance study of biofilter developed to treat H2S from wastewater odour.

    PubMed

    Omri, Ilhem; Aouidi, Fethia; Bouallagui, Hassib; Godon, Jean-Jacques; Hamdi, Moktar

    2013-04-01

    Biofiltration is an efficient biotechnological process used for waste gas abatement in various industrial processes. It offers low operating and capital costs and produces minimal secondary waste streams. The objective of this study was to evaluate the performance of a pilot scale biofilter in terms of pollutants' removal efficiencies and the bacterial dynamics under different inlet concentrations of H2S. The treatment of odourous pollutants by biofiltration was investigated at a municipal wastewater treatment plant (WWTP) (Charguia, Tunis, Tunisia). Sampling and analyses were conducted for 150 days. Inlet H2S concentration recorded was between 200 and 1300 mg H2S.m(-3). Removal efficiencies reached 99% for the majority of the running time at an empty bed retention time (EBRT) of 60 s. Heterotrophic bacteria were found to be the dominant microorganisms in the biofilter. The bacteria were identified as the members of the genus Bacillus, Pseudomonas and xanthomonadacea bacterium. The polymerase chain reaction-single stranded conformation polymorphism (PCR-SSCP) method showed that bacterial community profiles changed with the H2S inlet concentration. Our results indicated that the biofilter system, containing peat as the packing material, was proved able to remove H2S from the WWTP odourous pollutants. PMID:23961233

  4. Performance study of biofilter developed to treat H2S from wastewater odour

    PubMed Central

    Omri, Ilhem; Aouidi, Fethia; Bouallagui, Hassib; Godon, Jean-Jacques; Hamdi, Moktar

    2013-01-01

    Biofiltration is an efficient biotechnological process used for waste gas abatement in various industrial processes. It offers low operating and capital costs and produces minimal secondary waste streams. The objective of this study was to evaluate the performance of a pilot scale biofilter in terms of pollutants’ removal efficiencies and the bacterial dynamics under different inlet concentrations of H2S. The treatment of odourous pollutants by biofiltration was investigated at a municipal wastewater treatment plant (WWTP) (Charguia, Tunis, Tunisia). Sampling and analyses were conducted for 150 days. Inlet H2S concentration recorded was between 200 and 1300 mg H2S.m−3. Removal efficiencies reached 99% for the majority of the running time at an empty bed retention time (EBRT) of 60 s. Heterotrophic bacteria were found to be the dominant microorganisms in the biofilter. The bacteria were identified as the members of the genus Bacillus, Pseudomonas and xanthomonadacea bacterium. The polymerase chain reaction-single stranded conformation polymorphism (PCR-SSCP) method showed that bacterial community profiles changed with the H2S inlet concentration. Our results indicated that the biofilter system, containing peat as the packing material, was proved able to remove H2S from the WWTP odourous pollutants. PMID:23961233

  5. African penguins (Spheniscus demersus) can detect dimethyl sulphide, a prey-related odour.

    PubMed

    Cunningham, Gregory B; Strauss, Venessa; Ryan, Peter G

    2008-10-01

    Although it is well established that certain procellariiform seabirds use odour cues to find prey, it is not clear whether penguins use olfactory cues to forage. It is commonly assumed that penguins lack a sense of smell, yet they are closely related to procellariiforms and forage on similar types of prey in similar areas to many procellariiforms. Such regions are characterized by having high levels of dimethyl sulphide (DMS) a scented compound that many marine animals use to locate foraging grounds. If penguins can smell, DMS may be a biologically relevant scented compound that they may be sensitive to in nature. To test this hypothesis, we investigated whether adult African penguins (Spheniscus demersus) could detect DMS using two separate experiments. We tested wild penguins on Robben Island, South Africa, by deploying mumolar DMS solutions in the colonies, and found that birds slowed down their walking speeds. We also tested captive penguins in a Y-maze. In both cases, our data convincingly demonstrate that African penguins have a functioning sense of smell and are attracted to DMS. The implication of this work is that the detection of changes in the odour landscape (DMS) may assist penguins in identifying productive areas of the ocean for foraging. At-sea studies are needed to investigate this issue further.

  6. Supersensitive detection and discrimination of enantiomers by dorsal olfactory receptors: evidence for hierarchical odour coding.

    PubMed

    Sato, Takaaki; Kobayakawa, Reiko; Kobayakawa, Ko; Emura, Makoto; Itohara, Shigeyoshi; Kizumi, Miwako; Hamana, Hiroshi; Tsuboi, Akio; Hirono, Junzo

    2015-09-11

    Enantiomeric pairs of mirror-image molecular structures are difficult to resolve by instrumental analyses. The human olfactory system, however, discriminates (-)-wine lactone from its (+)-form rapidly within seconds. To gain insight into receptor coding of enantiomers, we compared behavioural detection and discrimination thresholds of wild-type mice with those of ΔD mice in which all dorsal olfactory receptors are genetically ablated. Surprisingly, wild-type mice displayed an exquisite "supersensitivity" to enantiomeric pairs of wine lactones and carvones. They were capable of supersensitive discrimination of enantiomers, consistent with their high detection sensitivity. In contrast, ΔD mice showed selective major loss of sensitivity to the (+)-enantiomers. The resulting 10(8)-fold differential sensitivity of ΔD mice to (-)- vs. (+)-wine lactone matched that observed in humans. This suggests that humans lack highly sensitive orthologous dorsal receptors for the (+)-enantiomer, similarly to ΔD mice. Moreover, ΔD mice showed >10(10)-fold reductions in enantiomer discrimination sensitivity compared to wild-type mice. ΔD mice detected one or both of the (-)- and (+)-enantiomers over a wide concentration range, but were unable to discriminate them. This "enantiomer odour discrimination paradox" indicates that the most sensitive dorsal receptors play a critical role in hierarchical odour coding for enantiomer identification.

  7. Avian Egg Odour Encodes Information on Embryo Sex, Fertility and Development

    PubMed Central

    Webster, Ben; Hayes, William; Pike, Thomas W.

    2015-01-01

    Avian chemical communication is a rapidly emerging field, but has been hampered by a critical lack of information on volatile chemicals that communicate ecologically relevant information (semiochemicals). A possible, but as yet unexplored, function of olfaction and chemical communication in birds is in parent-embryo and embryo-embryo communication. Communication between parents and developing embryos may act to mediate parental behaviour, while communication between embryos can control the synchronicity of hatching. Embryonic vocalisations and vibrations have been implicated as a means of communication during the later stages of development but in the early stages, before embryos are capable of independent movement and vocalisation, this is not possible. Here we show that volatiles emitted from developing eggs of Japanese quail (Coturnix japonica) convey information on egg fertility, along with the sex and developmental status of the embryo. Specifically, egg volatiles changed over the course of incubation, differed between fertile and infertile eggs, and were predictive of embryo sex as early as day 1 of incubation. Egg odours therefore have the potential to facilitate parent-embryo and embryo-embryo interactions by allowing the assessment of key measures of embryonic development long before this is possible through other modalities. It also opens up the intriguing possibility that parents may be able to glean further relevant information from egg volatiles, such as the health, viability and heritage of embryos. By determining information conveyed by egg-derived volatiles, we hope to stimulate further investigation into the ecological role of egg odours. PMID:25629413

  8. Developments in odour control and waste gas treatment biotechnology: a review.

    PubMed

    Burgess, J E; Parsons, S A; Stuetz, R M

    2001-02-01

    Waste and wastewater treatment processes produce odours, which can cause a nuisance to adjacent populations and contribute significantly to atmospheric pollution. Sulphurous compounds are responsible for acid rain and mist; many organic compounds of industrial origin contribute to airborne public health concerns, as well as environmental problems. Waste gases from industry have traditionally been treated using physicochemical processes, such as scrubbing, adsorption, condensation, and oxidation, however, biological treatment of waste gases has gained support as an effective and economical option in the past few decades. One emergent technique for biological waste gas treatment is the use of existing activated sludge plants as bioscrubbers, thus treating the foul air generated by other process units of the wastewater treatment system on site, with no requirement for additional units or for interruption of wastewater treatment. Limited data are available regarding the performance of activated sludge diffusion of odorous air in spite of numerous positive reports from full-scale applications in North America. This review argues that the information available is insufficient for precise process design and optimization, and simultaneous activated sludge treatment of wastewater and airborne odours could be adopted worldwide.

  9. Characterization and biological abatement of diffuse methane emissions and odour in an innovative wastewater treatment plant.

    PubMed

    Barcón, Tamara; Hernández, Jerónimo; Gómez-Cuervo, Santiago; Garrido, Juan M; Omil, Francisco

    2015-01-01

    An innovative and patented process for medium-high strength sewage which comprises an anaerobic step followed by a hybrid anoxic-aerobic chamber and a final ultrafiltration stage was characterized in terms of methane fugitive emissions as well as odours. The operation at ambient temperature implies higher methane content in the liquid anaerobic effluent, which finally causes concentrations around 0.01-2.4% in the off-gas released in the anoxic-aerobic chamber (1.25% average). Mass balances indicate that these emissions account for up to 30-35% of the total methane generated in the anaerobic reactor. A conventional biofilter (BF) operated at an empty bed residence time of 4 min was used to treat these emissions for 70 d. In spite of the fluctuations in the methane inlet concentrations derived from the operation of the wastewater treatment plant (WWTP), it was possible to operate at pseudo-steady-state conditions, achieving average removal efficiencies of 76.5% and maximum elimination capacities of 30.1 g m(-3) h(-1). Odour removal was quantified as 99.1%. Fluorescence in situ hybridization probes as well as metabolic activity assays demonstrated the suitability of the biomass developed in the WWTP as inoculum to start up the BF due to the presence of methanotrophic bacteria.

  10. How floral odours are learned inside the bumblebee ( Bombus terrestris) nest

    NASA Astrophysics Data System (ADS)

    Molet, Mathieu; Chittka, Lars; Raine, Nigel E.

    2009-02-01

    Recruitment in social insects often involves not only inducing nestmates to leave the nest, but also communicating crucial information about finding profitable food sources. Although bumblebees transmit chemosensory information (floral scent), the transmission mechanism is unknown as mouth-to-mouth fluid transfer (as in honeybees) does not occur. Because recruiting bumblebees release a pheromone in the nest that triggers foraging in previously inactive workers, we tested whether this pheromone helps workers learn currently rewarding floral odours, as found in food social learning in rats. We exposed colonies to artificial recruitment pheromone, paired with anise scent. The pheromone did not facilitate learning of floral scent. However, we found that releasing floral scent in the air of the colony was sufficient to trigger learning and that learning performance was improved when the chemosensory cue was provided in the nectar in honeypots; probably because it guarantees a tighter link between scent and reward, and possibly because gustatory cues are involved in addition to olfaction. Scent learning was maximal when anise-scented nectar was brought into the nest by demonstrator foragers, suggesting that previously unidentified cues provided by successful foragers play an important role in nestmates learning new floral odours.

  11. Odour maps in the brain of butterflies with divergent host-plant preferences.

    PubMed

    Carlsson, Mikael A; Bisch-Knaden, Sonja; Schäpers, Alexander; Mozuraitis, Raimondas; Hansson, Bill S; Janz, Niklas

    2011-01-01

    Butterflies are believed to use mainly visual cues when searching for food and oviposition sites despite that their olfactory system is morphologically similar to their nocturnal relatives, the moths. The olfactory ability in butterflies has, however, not been thoroughly investigated. Therefore, we performed the first study of odour representation in the primary olfactory centre, the antennal lobes, of butterflies. Host plant range is highly variable within the butterfly family Nymphalidae, with extreme specialists and wide generalists found even among closely related species. Here we measured odour evoked Ca(2+) activity in the antennal lobes of two nymphalid species with diverging host plant preferences, the specialist Aglais urticae and the generalist Polygonia c-album. The butterflies responded with stimulus-specific combinations of activated glomeruli to single plant-related compounds and to extracts of host and non-host plants. In general, responses were similar between the species. However, the specialist A. urticae responded more specifically to its preferred host plant, stinging nettle, than P. c-album. In addition, we found a species-specific difference both in correlation between responses to two common green leaf volatiles and the sensitivity to these compounds. Our results indicate that these butterflies have the ability to detect and to discriminate between different plant-related odorants.

  12. THE EFFECT OF ODOURS, IRRITANT VAPOURS, AND MENTAL WORK UPON THE BLOOD FLOW

    PubMed Central

    Shields, T. E.

    1896-01-01

    The most important of this investigation has been the completion of various improvements in the construction and use of the plethysmograph, by means of which numerous errors attending the use of the instrument have been eliminated. The results of the work show that all olfactory sensations, so far as they produce any effect through the vasomotor system, tend to diminish the volume of the arm, and therefore presumably cause a congestion of the brain. Whenever the stimulation occassions an increase in the volume of the arm, as sometimes happens, it seems to be due to acceleration of the heart rate, which, of course, tends also to increase the supply of blood to the brain. The of odours varies in extent with different individuals, and with the same individual at different times. It was most marked in subjects sensitive to odours. Irritant vapours, such as formic acid, have a marked effect in the same direction—that is, they cause a strong diminution in the volume of the arm. The experiments give no support to the view that pleasant sensations are accompanied by a diminution of the See PDF for Structure blood supply to the brain and unpleasant sensations by the reverse efeect. In all my experiments mental work caused a marked and prolonged diminution in the volume of the arm. This vasomotor effect was sometimes preceded by a transitory increase in the volume of the arm caused by acceleration of heart rate. PMID:19866796

  13. Gas recognition using a neural network approach to plasma optical emission spectroscopy

    NASA Astrophysics Data System (ADS)

    Hyland, Mark; Mariotti, Davide; Dubitzky, Werner; McLaughlin, James A.; Maguire, Paul

    2000-10-01

    A system has been developed which enables the detection and recognition of various gases. Plasma emission spectroscopy has been used to record spectra from volatile species of acetone, vinegar, and coffee beans, along with air and nitrogen spectra. The spectra have been uniquely processed and fed into an artificial neural network program for training and recognition of unknown gases. The system as a whole can be grouped into the emerging and diverse area of artificial nose technology. The sy stem has shown to provide a solution to the recognition of simple gases and odours (air, nitrogen, acetone) and could also satisfactorily recognise more complex samples (vinegar and coffee beans). Recognition is performed in seconds; this being a positive aspect for many artificial nose applications.

  14. Holistic processing predicts face recognition.

    PubMed

    Richler, Jennifer J; Cheung, Olivia S; Gauthier, Isabel

    2011-04-01

    The concept of holistic processing is a cornerstone of face-recognition research. In the study reported here, we demonstrated that holistic processing predicts face-recognition abilities on the Cambridge Face Memory Test and on a perceptual face-identification task. Our findings validate a large body of work that relies on the assumption that holistic processing is related to face recognition. These findings also reconcile the study of face recognition with the perceptual-expertise work it inspired; such work links holistic processing of objects with people's ability to individuate them. Our results differ from those of a recent study showing no link between holistic processing and face recognition. This discrepancy can be attributed to the use in prior research of a popular but flawed measure of holistic processing. Our findings salvage the central role of holistic processing in face recognition and cast doubt on a subset of the face-perception literature that relies on a problematic measure of holistic processing.

  15. Identification of food spoilage in the smart home based on neural and fuzzy processing of odour sensor responses.

    PubMed

    Green, Geoffrey C; Chan, Adrian D C; Goubran, Rafik A

    2009-01-01

    Adopting the use of real-time odour monitoring in the smart home has the potential to alert the occupant of unsafe or unsanitary conditions. In this paper, we measured (with a commercial metal-oxide sensor-based electronic nose) the odours of five household foods that had been left out at room temperature for a week to spoil. A multilayer perceptron (MLP) neural network was trained to recognize the age of the samples (a quantity related to the degree of spoilage). For four of these foods, median correlation coefficients (between target values and MLP outputs) of R > 0.97 were observed. Fuzzy C-means clustering (FCM) was applied to the evolving odour patterns of spoiling milk, which had been sampled more frequently (4h intervals for 7 days). The FCM results showed that both the freshest and oldest milk samples had a high degree of membership in "fresh" and "spoiled" clusters, respectively. In the future, as advancements in electronic nose development remove the present barriers to acceptance, signal processing methods like those explored in this paper can be incorporated into odour monitoring systems used in the smart home.

  16. Asymmetrical generalisation between pheromonal and floral odours in appetitive olfactory conditioning of the honey bee (Apis mellifera L.).

    PubMed

    Sandoz, J C; Pham-Delègue, M H; Renou, M; Wadhams, L J

    2001-09-01

    The capacity to generalise between similar but not identical olfactory stimuli is crucial for honey bees, allowing them to find rewarding food sources with varying volatile emissions. We studied bees' generalisation behaviour with odours having different biological values: typical floral odours or alarm compounds. Bees' behavioural and peripheral electrophysiological responses were investigated using a combined proboscis extension response conditioning-electroantennogram assay. Bees were conditioned to pure linalool (floral) or to pure isoamyl acetate (alarm) and were tested with different concentrations of both compounds. Electrophysiological responses were not influenced by conditioning, suggesting that the learning of individual compounds does not rely on modulations of peripheral sensitivity. Behaviourally, generalisation responses of bees conditioned to the alarm compound were much higher than those of bees conditioned to the floral odour. We further demonstrated such asymmetrical generalisation between alarm and floral odours by using differential conditioning procedures. Conditioning to alarm compounds (isoamyl acetate or 2-heptanone) consistently induced more generalisation than conditioning to floral compounds (linalool or phenylacetaldehyde). Interestingly, generalisation between the two alarm compounds, which are otherwise chemically different, was extremely high. These results are discussed in relation to the neural representation of compounds with different biological significance for bees. PMID:11730303

  17. Substituted hepta-1,6-dien-3-ones with green/fruity odours green/galbanum olfactophore model.

    PubMed

    Bajgrowicz, Jerzy A; Berg-Schultz, Katja; Brunner, Gerhard

    2003-07-01

    Following an analysis of available SAR data on green/galbanum-smelling molecules, a series of new 2-substituted hepta-1,6-dien-3-ones and their analogues were prepared and their olfactory properties evaluated. The study allowed to select efficient new odourants-potential substitutes for natural galbanum oil-and to generate an olfactophore model for the green/galbanum note.

  18. Wind tunnels vs. flux chambers: Area source emission measurements and the necessity for VOC and odour correction factors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wind tunnels and flux chambers have been used to measure fluxes of volatile organic compounds (VOC), odour, and ammonia (NH3) with little regard to air velocity or sweep air flow rates. As a result, flux measurements have been highly variable and scientists have been in disagreement as to the better...

  19. Digit ratio (2D:4D) predicts facial, but not voice or body odour, attractiveness in men.

    PubMed

    Ferdenzi, Camille; Lemaître, Jean-François; Leongómez, Juan David; Roberts, S Craig

    2011-12-01

    There is growing evidence that human second-to-fourth digit ratio (or 2D:4D) is related to facial features involved in attractiveness, mediated by in utero hormonal effects. The present study extends the investigation to other phenotypic, hormone-related determinants of human attractiveness: voice and body odour. Pictures of faces with a neutral expression, recordings of voices pronouncing vowels and axillary odour samples captured on cotton pads worn for 24 h were provided by 49 adult male donors. These stimuli were rated on attractiveness and masculinity scales by two groups of 49 and 35 females, approximately half of these in each sample using hormonal contraception. Multivariate regression analyses showed that males' lower (more masculine) right 2D:4D and lower right-minus-left 2D:4D (Dr-l) were associated with a more attractive (and in some cases more symmetrical), but not more masculine, face. However, 2D:4D and Dr-l did not predict voice and body odour masculinity or attractiveness. The results were interpreted in terms of differential effects of prenatal and circulating testosterone, male facial shape being supposedly more dependent on foetal levels (reflected by 2D:4D ratio), whereas body odour and vocal characteristics could be more dependent on variation in adult circulating testosterone levels. PMID:21508034

  20. Context affects nestmate recognition errors in honey bees and stingless bees.

    PubMed

    Couvillon, Margaret J; Segers, Francisca H I D; Cooper-Bowman, Roseanne; Truslove, Gemma; Nascimento, Daniela L; Nascimento, Fabio S; Ratnieks, Francis L W

    2013-08-15

    Nestmate recognition studies, where a discriminator first recognises and then behaviourally discriminates (accepts/rejects) another individual, have used a variety of methodologies and contexts. This is potentially problematic because recognition errors in discrimination behaviour are predicted to be context-dependent. Here we compare the recognition decisions (accept/reject) of discriminators in two eusocial bees, Apis mellifera and Tetragonisca angustula, under different contexts. These contexts include natural guards at the hive entrance (control); natural guards held in plastic test arenas away from the hive entrance that vary either in the presence or absence of colony odour or the presence or absence of an additional nestmate discriminator; and, for the honey bee, the inside of the nest. For both honey bee and stingless bee guards, total recognition errors of behavioural discrimination made by guards (% nestmates rejected + % non-nestmates accepted) are much lower at the colony entrance (honey bee: 30.9%; stingless bee: 33.3%) than in the test arenas (honey bee: 60-86%; stingless bee: 61-81%; P<0.001 for both). Within the test arenas, the presence of colony odour specifically reduced the total recognition errors in honey bees, although this reduction still fell short of bringing error levels down to what was found at the colony entrance. Lastly, in honey bees, the data show that the in-nest collective behavioural discrimination by ca. 30 workers that contact an intruder is insufficient to achieve error-free recognition and is not as effective as the discrimination by guards at the entrance. Overall, these data demonstrate that context is a significant factor in a discriminators' ability to make appropriate recognition decisions, and should be considered when designing recognition study methodologies.

  1. Generalization of learned predator recognition: an experimental test and framework for future studies.

    PubMed

    Ferrari, Maud C O; Gonzalo, Adega; Messier, François; Chivers, Douglas P

    2007-08-01

    While some prey species possess an innate recognition of their predators, others require learning to recognize their predators. The specific characteristics of the predators that prey learn and whether prey can generalize this learning to similar predatory threats have been virtually ignored. Here, we investigated whether fathead minnows that learned to chemically recognize a specific predator species as a threat has the ability to generalize their recognition to closely related predators. We found that minnows trained to recognize the odour of a lake trout as a threat (the reference predator) generalized their responses to brook trout (same genus as lake trout) and rainbow trout (same family), but did not generalize to a distantly related predatory pike or non-predatory suckers. We also found that the intensity of antipredator responses to the other species was correlated with the phylogenetic distance to the reference predator; minnows responded with a higher intensity response to brook trout than rainbow trout. This is the first study showing that prey have the ability to exhibit generalization of predator odour recognition. We discuss these results and provide a theoretical framework for future studies of generalization of predator recognition.

  2. Larval memory affects adult nest-mate recognition in the ant Aphaenogaster senilis

    PubMed Central

    Signorotti, Lisa; Jaisson, Pierre; d'Ettorre, Patrizia

    2014-01-01

    Prenatal olfactory learning has been demonstrated in a wide variety of animals, where it affects development and behaviour. Young ants learn the chemical signature of their colony. This cue-learning process allows the formation of a template used for nest-mate recognition in order to distinguish alien individuals from nest-mates, thus ensuring that cooperation is directed towards group members and aliens are kept outside the colony. To date, no study has investigated the possible effect of cue learning during early developmental stages on adult nest-mate recognition. Here, we show that odour familiarization during preimaginal life affects recognition abilities of adult Aphaenogaster senilis ants, particularly when the familiarization process occurs during the first larval stages. Ants eclosed from larvae exposed to the odour of an adoptive colony showed reduced aggression towards familiar, adoptive individuals belonging to this colony compared with alien individuals (true unfamiliar), but they remained non-aggressive towards adult individuals of their natal colony. Moreover, we found that the chemical similarity between the colony of origin and the adoptive colony does not influence the degree of aggression, meaning that the observed effect is likely to be due only to preimaginal learning experience. These results help understanding the developmental processes underlying efficient recognition systems. PMID:24258719

  3. Interactions of Carbon Dioxide and Food Odours in Drosophila: Olfactory Hedonics and Sensory Neuron Properties

    PubMed Central

    Faucher, Cécile P.; Hilker, Monika; de Bruyne, Marien

    2013-01-01

    Behavioural responses of animals to volatiles in their environment are generally dependent on context. Most natural odours are mixtures of components that can each induce different behaviours when presented on their own. We have investigated how a complex of two olfactory stimuli is evaluated by Drosophila flies in a free-flying two-trap choice assay and how these stimuli are encoded in olfactory receptor neurons. We first observed that volatiles from apple cider vinegar attracted flies while carbon dioxide (CO2) was avoided, confirming their inherent positive and negative values. In contradiction with previous results obtained from walking flies in a four-field olfactometer, in the present assay the addition of CO2 to vinegar increased rather than decreased the attractiveness of vinegar. This effect was female-specific even though males and females responded similarly to CO2 and vinegar on their own. To test whether the female-specific behavioural response to the mixture correlated with a sexual dimorphism at the peripheral level we recorded from olfactory receptor neurons stimulated with vinegar, CO2 and their combination. Responses to vinegar were obtained from three neuron classes, two of them housed with the CO2-responsive neuron in ab1 sensilla. Sensitivity of these neurons to both CO2 and vinegar per se did not differ between males and females and responses from female neurons did not change when CO2 and vinegar were presented simultaneously. We also found that CO2-sensitive neurons are particularly well adapted to respond rapidly to small concentration changes irrespective of background CO2 levels. The ability to encode temporal properties of stimulations differs considerably between CO2- and vinegar-sensitive neurons. These properties may have important implications for in-flight navigation when rapid responses to fragmented odour plumes are crucial to locate odour sources. However, the flies’ sex-specific response to the CO2-vinegar combination and the

  4. Odour and flavour thresholds of gasoline additives (MTBE, ETBE and TAME) and their occurrence in Dutch drinking water collection areas.

    PubMed

    van Wezel, Annemarie; Puijker, Leo; Vink, Cees; Versteegh, Ans; de Voogt, Pim

    2009-07-01

    The use of ETBE (ethyl-tert-butylether) as gasoline additive has recently grown rapidly. Contamination of aquatic systems is well documented for MTBE (methyl-tert-butylether), but less for other gasoline additives. Due to their mobility they may easily reach drinking water collection areas. Odour and flavour thresholds of MTBE are known to be low, but for ETBE and TAME (methyl-tert-amylether) hardly information is available. The objective here is to determine these thresholds for MTBE, ETBE and TAME, and relate these to concentrations monitored in thousands of samples from Dutch drinking water collection areas. For ETBE odour and flavour thresholds are low with 1-2microgL(-1), for MTBE and TAME they range from 7 to 16microg L(-1). In most groundwater collection areas MTBE concentrations are below 0.1microg L(-1). In phreatic groundwaters in sandy soils not covered by a protective soil layer, occasionally MTBE occurs at higher concentrations. For surface water collection areas a minority of the locations is free of MTBE. For river bank and dune infiltrates, at a few locations the odour and flavour threshold is exceeded. For ETBE fewer monitoring data are available. ETBE was found in 2 out of 37 groundwater collection areas, in concentrations below 1microgL(-1). In the surface water collection areas monitored ETBE was found in concentrations near to the odour and flavour thresholds. The low odour and flavour thresholds combined with the high mobility and persistence of these compounds, their high production volumes and their increased use may yield problems with future production of drinking water.

  5. Indoor mildew odour in old housing was associated with adult allergic symptoms, asthma, chronic bronchitis, vision, sleep and self-rated health: USA NHANES, 2005-2006.

    PubMed

    Shiue, Ivy

    2015-09-01

    A recent systematic review and meta-analysis has shown the effect of indoor mildew odour on allergic rhinitis risk, but its relation to other common chronic health outcomes in adults has not been investigated. Therefore, it was aimed to examine the relationship of indoor mildew odour and common health outcomes in adults in a national and population-based setting. Data was retrieved from the United States National Health and Nutrition Examination Surveys, 2005-2006, including the available information on demographics, housing characteristics, self-reported health conditions and urinary concentrations of environmental chemicals. T test, chi-squared test and survey-weighted logistic regression modelling were performed. Of all American adults (n = 4979), 744 (15.1%) reported indoor mildew odour or musty smell in their households. People who reported indoor mildew odour or musty smell also reported poorer self-rated health, sleep complaints, chronic bronchitis, asthma attack, itchy rash, sneezing and poor vision. In addition, people who reported indoor mildew odour or musty smell also tended to reside in older housing that were built 20 years earlier. However, there were no significant statistical associations found between indoor mildew odour or musty smell and urinary concentrations of environmental chemicals, which was also found to be associated with old housing. People who lived in older housing with indoor mildew odour or musty smell tended to have chronic health problems. To protect occupants in old housing from chronic illnesses associated with indoor mildew odour, elimination of the odour sources should be explored in future research and therefore public health and housing programs. Graphical abstract Pathway from old housing to musty smell, environmental chemicals and then health outcomes. PMID:25971810

  6. Green chemistry procedure for the synthesis of cyclic ketals from 2-adamantanone as potential cosmetic odourants.

    PubMed

    Genta, M T; Villa, C; Mariani, E; Longobardi, M; Loupy, A

    2002-10-01

    Some cyclic ketals derived from 2-adamantanone were obtained in excellent yields by microwave activation under solvent-free conditions, as a 'green chemistry' procedure. A number of experiments were performed to evaluate the most efficient catalytic conditions. The best results were obtained using a simple heterogeneous mixture of reagents and p-toluenesulphonic acid as the catalyst, without any solvent or support. The data are reported and compared with those obtained by other microwave-mediated syntheses or by classical method. In order to check the possible intervention of non-thermal microwave effects, the best experiment in 'dry media' was carried out with considerable lower yield by conventional heating, in a thermostated oil bath, under the same conditions as under microwaves (time, temperature and vessel). All the synthesized compounds were tested for their olfactive character and for a potential cosmetic use. The odour evaluation is reported. PMID:18498518

  7. UV/chlorine control of drinking water taste and odour at pilot and full-scale.

    PubMed

    Wang, Ding; Bolton, James R; Andrews, Susan A; Hofmann, Ron

    2015-10-01

    Advanced oxidation processes (AOPs) can be used to destroy taste and odour-causing compounds in drinking water. This work investigated both pilot- and full-scale performance of the novel ultraviolet (UV)/chlorine AOP for the destruction of geosmin, 2-methylisoborneol (MIB) and caffeine (as a surrogate) in two different surface waters. The efficiency of the UV/chlorine process at pH 7.5 and 8.5 was comparable to that of the UV/hydrogen peroxide (UV/H2O2) process under parallel conditions, and was superior at pH 6.5. Caffeine was found to be a suitable surrogate for geosmin and MIB, and could be used as a more economical alternative to geosmin or MIB spiking for site-specific full-scale testing.

  8. Parasite-induced alteration of odour responses in an amphipod-acanthocephalan system.

    PubMed

    Stone, Charles F; Moore, Janice

    2014-11-01

    Odour-related behaviours in aquatic invertebrates are important and effective anti-predator behaviours. Parasites often alter invertebrate host behaviours to increase transmission to hosts. This study investigated the responses of the amphipod Hyalella azteca when presented with two predator chemical cues: (i) alarm pheromones produced by conspecifics and (ii) kairomones produced by a predatory Green Sunfish (Lepomis cyanellus). We compared the responses of amphipods uninfected and infected with the acanthocepalan parasite Leptorhynchiodes thecatus. Uninfected amphipods reduced activity and increased refuge use after detecting both the alarm pheromones and predator kairomones. Infected amphipods spent significantly more time being active and less time on the refuge than uninfected amphipods, and behaved as if they had not detected the chemical stimulus. Therefore, L. thecatus infections disrupt the amphipods' anti-predator behaviours and likely make their hosts more susceptible to predation. PMID:25200352

  9. Odour cues from suitors' nests determine mating success in a fish.

    PubMed

    Lehtonen, Topi K; Kvarnemo, Charlotta

    2015-05-01

    Animals use a range of sensory cues for finding food, avoiding predators and choosing mates. In this regard, the aquatic environment is particularly suitable for the use of olfactory and other chemical cues. Nevertheless, mate choice research, even on aquatic organisms, has focused on visual signals, while chemical cues relevant in sexual selection have been assumed to be 'intrinsic' excretions of mate candidates. Here, using the sand goby Pomatoschistus minutus, a small fish with paternal egg care, we investigated the possibility that 'extrinsic' chemical cues in the males' nests could also have a significant contribution to mating success. We found that females strongly avoided laying eggs into nests subject to the odour of Saprolegnia water moulds (an egg infection) and that this effect was independent of the females' initial, visually based preference for males. To the best of our knowledge, this is the first study to show that chemical cues related to parental failure can play a large role in sexual selection.

  10. Notch1 activity in the olfactory bulb is odour-dependent and contributes to olfactory behaviour.

    PubMed

    Brai, Emanuele; Marathe, Swananda; Zentilin, Lorena; Giacca, Mauro; Nimpf, Johannes; Kretz, Robert; Scotti, Alessandra; Alberi, Lavinia

    2014-11-01

    Notch signalling plays an important role in synaptic plasticity, learning and memory functions in both Drosophila and rodents. In this paper, we report that this feature is not restricted to hippocampal networks but also involves the olfactory bulb (OB). Odour discrimination and olfactory learning in rodents are essential for survival. Notch1 expression is enriched in mitral cells of the mouse OB. These principal neurons are responsive to specific input odorants and relay the signal to the olfactory cortex. Olfactory stimulation activates a subset of mitral cells, which show an increase in Notch activity. In Notch1cKOKln mice, the loss of Notch1 in mitral cells affects the magnitude of the neuronal response to olfactory stimuli. In addition, Notch1cKOKln mice display reduced olfactory aversion to propionic acid as compared to wildtype controls. This indicates, for the first time, that Notch1 is involved in olfactory processing and may contribute to olfactory behaviour.

  11. Odour-mediated orientation of beetles is influenced by age, sex and morph.

    PubMed

    Arnold, Sarah E J; Stevenson, Philip C; Belmain, Steven R

    2012-01-01

    The behaviour of insects is dictated by a combination of factors and may vary considerably between individuals, but small insects are often considered en masse and thus these differences can be overlooked. For example, the cowpea bruchid Callosobruchus maculatus F. exists naturally in two adult forms: the active (flight) form for dispersal, and the inactive (flightless), more fecund but shorter-lived form. Given that these morphs show dissimilar biology, it is possible that they differ in odour-mediated orientation and yet studies of this species frequently neglect to distinguish morph type, or are carried out only on the inactive morph. Along with sex and age of individual, adult morph could be an important variable determining the biology of this and similar species, informing studies on evolution, ecology and pest management. We used an olfactometer with motion-tracking to investigate whether the olfactory behaviour and orientation of C. maculatus towards infested and uninfested cowpeas and a plant-derived repellent compound, methyl salicylate, differed between morphs or sexes. We found significant differences between the behaviour of male and female beetles and beetles of different ages, as well as interactive effects of sex, morph and age, in response to both host and repellent odours. This study demonstrates that behavioural experiments on insects should control for sex and age, while also considering differences between adult morphs where present in insect species. This finding has broad implications for fundamental entomological research, particularly when exploring the relationships between physiology, behaviour and evolutionary biology, and the application of crop protection strategies.

  12. Odour-Mediated Orientation of Beetles Is Influenced by Age, Sex and Morph

    PubMed Central

    Arnold, Sarah E. J.; Stevenson, Philip C.; Belmain, Steven R.

    2012-01-01

    The behaviour of insects is dictated by a combination of factors and may vary considerably between individuals, but small insects are often considered en masse and thus these differences can be overlooked. For example, the cowpea bruchid Callosobruchus maculatus F. exists naturally in two adult forms: the active (flight) form for dispersal, and the inactive (flightless), more fecund but shorter-lived form. Given that these morphs show dissimilar biology, it is possible that they differ in odour-mediated orientation and yet studies of this species frequently neglect to distinguish morph type, or are carried out only on the inactive morph. Along with sex and age of individual, adult morph could be an important variable determining the biology of this and similar species, informing studies on evolution, ecology and pest management. We used an olfactometer with motion-tracking to investigate whether the olfactory behaviour and orientation of C. maculatus towards infested and uninfested cowpeas and a plant-derived repellent compound, methyl salicylate, differed between morphs or sexes. We found significant differences between the behaviour of male and female beetles and beetles of different ages, as well as interactive effects of sex, morph and age, in response to both host and repellent odours. This study demonstrates that behavioural experiments on insects should control for sex and age, while also considering differences between adult morphs where present in insect species. This finding has broad implications for fundamental entomological research, particularly when exploring the relationships between physiology, behaviour and evolutionary biology, and the application of crop protection strategies. PMID:23145074

  13. Automatic speech recognition

    NASA Astrophysics Data System (ADS)

    Espy-Wilson, Carol

    2005-04-01

    Great strides have been made in the development of automatic speech recognition (ASR) technology over the past thirty years. Most of this effort has been centered around the extension and improvement of Hidden Markov Model (HMM) approaches to ASR. Current commercially-available and industry systems based on HMMs can perform well for certain situational tasks that restrict variability such as phone dialing or limited voice commands. However, the holy grail of ASR systems is performance comparable to humans-in other words, the ability to automatically transcribe unrestricted conversational speech spoken by an infinite number of speakers under varying acoustic environments. This goal is far from being reached. Key to the success of ASR is effective modeling of variability in the speech signal. This tutorial will review the basics of ASR and the various ways in which our current knowledge of speech production, speech perception and prosody can be exploited to improve robustness at every level of the system.

  14. Pattern Perception and Pictures for the Blind

    ERIC Educational Resources Information Center

    Heller, Morton A.; McCarthy, Melissa; Clark, Ashley

    2005-01-01

    This article reviews recent research on perception of tangible pictures in sighted and blind people. Haptic picture naming accuracy is dependent upon familiarity and access to semantic memory, just as in visual recognition. Performance is high when haptic picture recognition tasks do not depend upon semantic memory. Viewpoint matters for the ease…

  15. Disturbances of spatial perception in children.

    PubMed

    Meerwaldt, J D; van Dongen, H R

    1988-12-01

    Spatial perception was tested in 12 children with a localized brain lesion by means of the rod orientation test, line orientation test and facial recognition test. Only children with a lesion of the right hemisphere showed a disturbance of spatial perception.

  16. The Role of Object Recognition in Young Infants' Object Segregation.

    ERIC Educational Resources Information Center

    Carey, Susan; Williams, Travis

    2001-01-01

    Discusses Needham's findings by asserting that they extend understanding of infant perception by showing that the memory representations infants draw upon have bound together information about shape, color, and pattern. Considers the distinction between two senses of "recognition" and asks in which sense object recognition contributes to object…

  17. Recognition-by-Components: A Theory of Human Image Understanding.

    ERIC Educational Resources Information Center

    Biederman, Irving

    1987-01-01

    The theory proposed (recognition-by-components) hypothesizes the perceptual recognition of objects to be a process in which the image of the input is segmented at regions of deep concavity into an arrangement of simple geometric components. Experiments on the perception of briefly presented pictures support the theory. (Author/LMO)

  18. The attraction of virgin female hide beetles (Dermestes maculatus) to cadavers by a combination of decomposition odour and male sex pheromones

    PubMed Central

    2012-01-01

    Introduction The hide beetle Dermestes maculatus (Coleoptera: Dermestidae) feeds as an adult and larva on decomposing animal remains and can also be found on human corpses. Therefore, forensic entomological questions with regard to when and how the first receptive females appear on carcasses are important, as the developmental stages of their larvae can be used to calculate the post-mortem interval. To date, we know that freshly emerged males respond to the cadaver odour of post-bloated carcasses (approximately 9 days after death at Tmean = 27°C), being attracted by benzyl butyrate. This component occurs at its highest concentration at this stage of decay. The aim of our study was to determine the principle of attraction of virgin females to the feeding and breeding substrate. For this purpose, we tested the response of these females to headspace samples of piglet cadavers and male sex pheromones [(Z9)-unsaturated fatty acid isopropyl esters] in a Y-olfactometer. Because we expected that such an odour combination is of importance for virgin female attraction, we tested the following two questions: 1) Are virgin female hide beetles attracted by a combination of cadaver odour and male sex pheromones? 2) During which decomposition stage do the first virgin females respond to cadaver odour when combined with male sex pheromones? Results We found that young virgin females were attracted to the cadaver by a combination of cadaver odour and male sex pheromones. Neither cadaver odour alone nor male sex pheromones alone was significantly more attractive than a solvent control. Our results also gave a weak indication that the first young virgin females respond as early as the post-bloating stage to its associated decomposition odour when combined with male sex pheromones. Conclusions Our results indicate that freshly emerged males possibly respond to cadaver odour and visit carcasses before virgin females. Being attracted to cadavers when male sex pheromone is perceived as

  19. Visual stimuli induced by self-motion and object-motion modify odour-guided flight of male moths (Manduca sexta L.).

    PubMed

    Verspui, Remko; Gray, John R

    2009-10-01

    Animals rely on multimodal sensory integration for proper orientation within their environment. For example, odour-guided behaviours often require appropriate integration of concurrent visual cues. To gain a further understanding of mechanisms underlying sensory integration in odour-guided behaviour, our study examined the effects of visual stimuli induced by self-motion and object-motion on odour-guided flight in male M. sexta. By placing stationary objects (pillars) on either side of a female pheromone plume, moths produced self-induced visual motion during odour-guided flight. These flights showed a reduction in both ground and flight speeds and inter-turn interval when compared with flight tracks without stationary objects. Presentation of an approaching 20 cm disc, to simulate object-motion, resulted in interrupted odour-guided flight and changes in flight direction away from the pheromone source. Modifications of odour-guided flight behaviour in the presence of stationary objects suggest that visual information, in conjunction with olfactory cues, can be used to control the rate of counter-turning. We suggest that the behavioural responses to visual stimuli induced by object-motion indicate the presence of a neural circuit that relays visual information to initiate escape responses. These behavioural responses also suggest the presence of a sensory conflict requiring a trade-off between olfactory and visually driven behaviours. The mechanisms underlying olfactory and visual integration are discussed in the context of these behavioural responses.

  20. Study of the art: canine olfaction used for cancer detection on the basis of breath odour. Perspectives and limitations.

    PubMed

    Jezierski, Tadeusz; Walczak, Marta; Ligor, Tomasz; Rudnicka, Joanna; Buszewski, Bogusław

    2015-05-06

    Experimental studies using trained dogs to identify breath odour markers of human cancer, published in the recent decade, have been analyzed and compared with the authors' own results. Particular published studies differ as regards the experimental setup, kind of odour samples (breath, urine, tumor tissue, serum), sample collection methods, dogs' characteristics and dog training methods as well as in results presented in terms of detection sensitivity and specificity. Generally it can be stated that trained dogs are able to distinguish breath odour samples typical for patients with lung cancer and other cancers from samples typical for healthy humans at a 'better than by chance' rate. Dogs' indications were positively correlated with content of 2-pentanone and ethyl acetate (r = 0.97 and r = 0.85 respectively) and negatively correlated with 1-propanol and propanal in breath samples (r = -0.98 and -0.87 respectively). The canine method has some advantages as a potential cancer-screening method, due to its non-invasiveness, simplicity of odour sampling and storage, ease of testing and interpretation of results and relatively low costs. Disadvantages and limitations of this method are related to the fact that it is still not known exactly to which chemical compounds and/or their combinations the dogs react. So far it could not be confirmed that dogs are able to sniff out early preclinical cancer stages with approximately the same accuracy as already diagnosed cases. The detection accuracy may vary due to failure in conditioning of dogs, decreasing motivation or confounding factors. The dogs' performance should be systematically checked in rigorous double-blind procedures. Recommendations for methodological standardization have been proposed.

  1. Evaluation of a novel wind tunnel for the measurement of the kinetics of odour emissions from piggery effluent.

    PubMed

    Sohn, J H; Smith, R; Yoong, E; Hudson, N; Kim, T I

    2004-01-01

    A novel laboratory wind tunnel, with the capability to control factors such as air flow-rate, was developed to measure the kinetics of odour emissions from liquid effluent. The tunnel allows the emission of odours and other volatiles under an atmospheric transport system similar to ambient conditions. Sensors for wind speed, temperature and humidity were installed and calibrated. To calibrate the wind tunnel, trials were performed to determine the gas recovery efficiency under different air flow-rates (ranging from 0.001 to 0.028m3/s) and gas supply rates (ranging from 2.5 to 10.0 L/min) using a standard CO gas mixture. The results have shown gas recovery efficiencies ranging from 61.7 to 106.8%, while the average result from the trials was 81.14%. From statistical analysis, it was observed that the highest, most reliable gas recovery efficiency of the tunnel was 88.9%. The values of air flow-rate and gas supply rate corresponding to the highest gas recovery efficiency were 0.028 m3/s and 10.0 L/min respectively. This study suggested that the wind tunnel would provide precise estimates of odour emission rate. However, the wind tunnel needs to be calibrated to compensate for errors caused by different air flow-rates.

  2. Effect of matured compost as an inoculating agent on odour removal and maturation of vegetable and fruit waste compost.

    PubMed

    Chen, Chih-Yu; Kuo, Jong-Tar; Chung, Ying-Chien

    2013-01-01

    The use of matured compost as an inoculation agent to improve the composting of vegetable and fruit wastes in a laboratory-scale composter was evaluated, and the commercial feasibility of this approach in a pilot-scale (1.8 x 10(4) L) composter was subsequently confirmed. The effect of aeration rate on the physico-chemical and biological properties of compost was also studied. Aeration rate affected the fermentation temperature, moisture content, pH, O2 consumption rate, CO2 production rate and the formation of odour. The optimal aeration rate was 2.5 L air/kg dry solid/min. The CO2 production rate approached the theoretical value during composting and was linearly dependent on temperature, indicating that the compost system had good operating characteristics. The inoculation of cellulolytic bacteria and deodorizing bacteria to compost in the pilot-scale composter led to an 18.2% volatile solids loss and a 64.3% volume reduction ratio in 52 h; only 1.5 ppm(v) odour was detected. This is the first study to focus on both operating performance and odour removal in a pilot-scale composter. PMID:23530345

  3. Disruption of Kcc2-dependent inhibition of olfactory bulb output neurons suggests its importance in odour discrimination.

    PubMed

    Gödde, Kathrin; Gschwend, Olivier; Puchkov, Dmytro; Pfeffer, Carsten K; Carleton, Alan; Jentsch, Thomas J

    2016-01-01

    Synaptic inhibition in the olfactory bulb (OB), the first relay station of olfactory information, is believed to be important for odour discrimination. We interfered with GABAergic inhibition of mitral and tufted cells (M/T cells), the principal neurons of the OB, by disrupting their potassium-chloride cotransporter 2 (Kcc2). Roughly, 70% of mice died around 3 weeks, but surviving mice appeared normal. In these mice, the resulting increase in the intracellular Cl(-) concentration nearly abolished GABA-induced hyperpolarization of mitral cells (MCs) and unexpectedly increased the number of perisomatic synapses on MCs. In vivo analysis of odorant-induced OB electrical activity revealed increased M/T cell firing rate, altered phasing of action potentials in the breath cycle and disrupted separation of odour-induced M/T cell activity patterns. Mice also demonstrated a severely impaired ability to discriminate chemically similar odorants or odorant mixtures. Our work suggests that precisely tuned GABAergic inhibition onto M/T cells is crucial for M/T cell spike pattern separation needed to distinguish closely similar odours. PMID:27389623

  4. Disruption of Kcc2-dependent inhibition of olfactory bulb output neurons suggests its importance in odour discrimination

    PubMed Central

    Gödde, Kathrin; Gschwend, Olivier; Puchkov, Dmytro; Pfeffer, Carsten K.; Carleton, Alan; Jentsch, Thomas J.

    2016-01-01

    Synaptic inhibition in the olfactory bulb (OB), the first relay station of olfactory information, is believed to be important for odour discrimination. We interfered with GABAergic inhibition of mitral and tufted cells (M/T cells), the principal neurons of the OB, by disrupting their potassium-chloride cotransporter 2 (Kcc2). Roughly, 70% of mice died around 3 weeks, but surviving mice appeared normal. In these mice, the resulting increase in the intracellular Cl− concentration nearly abolished GABA-induced hyperpolarization of mitral cells (MCs) and unexpectedly increased the number of perisomatic synapses on MCs. In vivo analysis of odorant-induced OB electrical activity revealed increased M/T cell firing rate, altered phasing of action potentials in the breath cycle and disrupted separation of odour-induced M/T cell activity patterns. Mice also demonstrated a severely impaired ability to discriminate chemically similar odorants or odorant mixtures. Our work suggests that precisely tuned GABAergic inhibition onto M/T cells is crucial for M/T cell spike pattern separation needed to distinguish closely similar odours. PMID:27389623

  5. Responses to colour and host odour cues in three cereal pest species, in the context of ecology and control.

    PubMed

    Arnold, S E J; Stevenson, P C; Belmain, S R

    2015-08-01

    Many insects show a greater attraction to multimodal cues, e.g. odour and colour combined, than to either cue alone. Despite the potential to apply the knowledge to improve control strategies, studies of multiple stimuli have not been undertaken for stored product pest insects. We tested orientation towards a food odour (crushed white maize) in combination with a colour cue (coloured paper with different surface spectral reflectance properties) in three storage pest beetle species, using motion tracking to monitor their behaviour. While the maize weevil, Sitophilus zeamais (Motsch.), showed attraction to both odour and colour stimuli, particularly to both cues in combination, this was not observed in the bostrichid pests Rhyzopertha dominica (F.) (lesser grain borer) or Prostephanus truncatus (Horn) (larger grain borer). The yellow stimulus was particularly attractive to S. zeamais, and control experiments showed that this was neither a result of the insects moving towards darker-coloured areas of the arena, nor their being repelled by optical brighteners in white paper. Visual stimuli may play a role in location of host material by S. zeamais, and can be used to inform trap design for the control or monitoring of maize weevils. The lack of visual responses by the two grain borers is likely to relate to their different host-seeking behaviours and ecological background, which should be taken into account when devising control methods. PMID:25916219

  6. Responses to colour and host odour cues in three cereal pest species, in the context of ecology and control.

    PubMed

    Arnold, S E J; Stevenson, P C; Belmain, S R

    2015-08-01

    Many insects show a greater attraction to multimodal cues, e.g. odour and colour combined, than to either cue alone. Despite the potential to apply the knowledge to improve control strategies, studies of multiple stimuli have not been undertaken for stored product pest insects. We tested orientation towards a food odour (crushed white maize) in combination with a colour cue (coloured paper with different surface spectral reflectance properties) in three storage pest beetle species, using motion tracking to monitor their behaviour. While the maize weevil, Sitophilus zeamais (Motsch.), showed attraction to both odour and colour stimuli, particularly to both cues in combination, this was not observed in the bostrichid pests Rhyzopertha dominica (F.) (lesser grain borer) or Prostephanus truncatus (Horn) (larger grain borer). The yellow stimulus was particularly attractive to S. zeamais, and control experiments showed that this was neither a result of the insects moving towards darker-coloured areas of the arena, nor their being repelled by optical brighteners in white paper. Visual stimuli may play a role in location of host material by S. zeamais, and can be used to inform trap design for the control or monitoring of maize weevils. The lack of visual responses by the two grain borers is likely to relate to their different host-seeking behaviours and ecological background, which should be taken into account when devising control methods.

  7. The olfactory system of the tammar wallaby is developed at birth and directs the neonate to its mother's pouch odours.

    PubMed

    Schneider, Nanette Y; Fletcher, Terrence P; Shaw, Geoff; Renfree, Marilyn B

    2009-11-01

    In kangaroos and wallabies at birth the highly altricial newborn young climbs unassisted from the urogenital opening to the teat. Negative geotropism is important for the initial climb to the pouch opening, but nothing is known of the signals that then direct the neonate downwards to the teat. Here we show that the newborn tammar wallaby (Macropus eugenii) has the olfactory apparatus to detect smell. Both the main olfactory system and vomeronasal organ (VNO) are developed at the time of birth. Receptor cells of the main olfactory epithelium immunopositive for G(oalpha)-protein project to the three layered main olfactory bulb (MOB). The receptor epithelium of the VNO contains G-protein immunopositive cells and has olfactory knob-like structures. The VNO is connected to an area between the two MOBs. Next, using a functional test, we show that neonates can respond to odours from their mother's pouch. When neonatal young are presented with a choice of a pouch-odour-soaked swab or a saline swab, they choose the swab with their mother's pouch secretions significantly more often (P<0.05) than the saline swab. We conclude that both olfactory systems are capable of receiving odour signals at birth, a function that must be a critical adaptation for the survival of an altricial marsupial neonate such as the tammar for its journey to the pouch.

  8. Recognition Tunneling

    PubMed Central

    Lindsay, Stuart; He, Jin; Sankey, Otto; Hapala, Prokop; Jelinek, Pavel; Zhang, Peiming; Chang, Shuai; Huang, Shuo

    2010-01-01

    Single molecules in a tunnel junction can now be interrogated reliably using chemically-functionalized electrodes. Monitoring stochastic bonding fluctuations between a ligand bound to one electrode and its target bound to a second electrode (“tethered molecule-pair” configuration) gives insight into the nature of the intermolecular bonding at a single molecule-pair level, and defines the requirements for reproducible tunneling data. Simulations show that there is an instability in the tunnel gap at large currents, and this results in a multiplicity of contacts with a corresponding spread in the measured currents. At small currents (i.e. large gaps) the gap is stable, and functionalizing a pair of electrodes with recognition reagents (the “free analyte” configuration) can generate a distinct tunneling signal when an analyte molecule is trapped in the gap. This opens up a new interface between chemistry and electronics with immediate implications for rapid sequencing of single DNA molecules. PMID:20522930

  9. Bidirectional Modulation of Recognition Memory

    PubMed Central

    Ho, Jonathan W.; Poeta, Devon L.; Jacobson, Tara K.; Zolnik, Timothy A.; Neske, Garrett T.; Connors, Barry W.

    2015-01-01

    Perirhinal cortex (PER) has a well established role in the familiarity-based recognition of individual items and objects. For example, animals and humans with perirhinal damage are unable to distinguish familiar from novel objects in recognition memory tasks. In the normal brain, perirhinal neurons respond to novelty and familiarity by increasing or decreasing firing rates. Recent work also implicates oscillatory activity in the low-beta and low-gamma frequency bands in sensory detection, perception, and recognition. Using optogenetic methods in a spontaneous object exploration (SOR) task, we altered recognition memory performance in rats. In the SOR task, normal rats preferentially explore novel images over familiar ones. We modulated exploratory behavior in this task by optically stimulating channelrhodopsin-expressing perirhinal neurons at various frequencies while rats looked at novel or familiar 2D images. Stimulation at 30–40 Hz during looking caused rats to treat a familiar image as if it were novel by increasing time looking at the image. Stimulation at 30–40 Hz was not effective in increasing exploration of novel images. Stimulation at 10–15 Hz caused animals to treat a novel image as familiar by decreasing time looking at the image, but did not affect looking times for images that were already familiar. We conclude that optical stimulation of PER at different frequencies can alter visual recognition memory bidirectionally. SIGNIFICANCE STATEMENT Recognition of novelty and familiarity are important for learning, memory, and decision making. Perirhinal cortex (PER) has a well established role in the familiarity-based recognition of individual items and objects, but how novelty and familiarity are encoded and transmitted in the brain is not known. Perirhinal neurons respond to novelty and familiarity by changing firing rates, but recent work suggests that brain oscillations may also be important for recognition. In this study, we showed that

  10. Costs of female odour in males of the parasitic wasp Lariophagus distinguendus (Hymenoptera: Pteromalidae)

    NASA Astrophysics Data System (ADS)

    Ruther, Joachim; Steiner, Sven

    2008-06-01

    The display of female traits by males is widespread in the animal kingdom. In several species, this phenomenon has been shown to function adaptively as a male mating strategy to deceive sexual rivals (female mimicry). Freshly emerged males of the parasitic wasp Lariophagus distinguendus (Hymenoptera: Pteromalidae) are perceived by other males as if they were females because of a very similar composition of cuticular hydrocarbons which function as a sex pheromone in this species inducing courtship behaviour in males. Within 32 h, however, males deactivate the pheromone and are no longer courted by other males. In this paper, behavioural experiments were performed to test hypotheses on potential costs and benefits associated with the female odour in young males. We did not find any benefits, but demonstrated that young males were significantly more often outrivaled in male-male contests when competing with two older males for a female. Also, young males were significantly more often mounted in homosexual courtship events during these contests. Thus, display of female traits by males is not necessarily beneficial, and in fact, can be disadvantageous. We suggest that these costs have favoured the evolution of the pheromone deactivation mechanism in L. distinguendus males. The function of cuticular hydrocarbons as a female courtship pheromone in L. distinguendus might have evolved secondarily from a primary function relevant for both genders, and the deactivation of the signal in males might have caused a shift of specificity of the chemical signal from the species level to the sex level.

  11. Ants use odour cues to exploit fig-fig wasp interactions

    NASA Astrophysics Data System (ADS)

    Schatz, Bertrand; Hossaert-McKey, Martine

    2010-01-01

    Fig wasps may constitute a relatively abundant food source for ants associated with the fig-fig wasp nursery pollination mutualism. We found previously that a Mediterranean ant species detects fig wasps by chemical signals. In this paper we want to test the generality of this finding by studying two tropical ants, Oecophylla smaragdina and Crematogaster sp., preying on fig wasps on the dioecious Ficus fistulosa in Brunei (Borneo). Behavioural tests in a Y-tube olfactometer showed that these two ants were attracted both to odours emitted by receptive figs and to those emitted by fig wasps (male and female of the pollinator, and a non-pollinating fig wasp) used here as a kairomone. Naïve workers were not attracted to fig wasps, suggesting that olfactory learning may play a role in prey detection. We also found that O. smaragdina was much more likely to be present on figs of male trees (where fig wasps are more abundant), and that the abundance of this ant species varied strongly with developmental phase of figs on individual trees. Moreover, its aggressiveness was also strongly influenced by the nature of the object presented in our behavioural tests, the site of the test and the developmental phase of the fig tested. Investigation on the chemical and behavioural ecology of the different interacting species provides important insights into the intricate relationships supported by the fig-fig wasp mutualism.

  12. Efficient taste and odour removal by water treatment plants around the Han River water supply system.

    PubMed

    Ahn, H; Chae, S; Kim, S; Wang, C; Summers, R S

    2007-01-01

    Seven major water treatment plants in Seoul Metropolitan Area, which are under Korea Water Resources Corporation (KOWACO)'s management, take water from the Paldang Reservoir in the Han River System for drinking water supply. There are taste and odour (T&O) problems in the finished water because the conventional treatment processes do not efficiently remove the T&O compounds. This study evaluated T&O removal by ozonation, granular activated carbon (GAC) treatment, powder activated carbon (PAC) and an advanced oxidation process in a pilot-scale treatment plant and bench-scale laboratory experiments. During T&O episodes, PAC alone was not adequate, but as a pretreatment together with GAC it could be a useful option. The optimal range of ozone dose was 1 to 2 mg/L at a contact time of 10 min. However, with ozone alone it was difficult to meet the T&O target of 3 TON and 15 ng/L of MIB or geosmin. The GAC adsorption capacity for DOC in the three GAC systems (F/A, GAC and O3 + GAC) at an EBCT of 14 min is mostly exhausted after 9 months. However, substantial TON removal continued for more than 2 years (>90,000 bed volumes). GAC was found to be effective for T&O control and the main removal mechanisms were adsorption capacity and biodegradation. PMID:17489399

  13. City dweller responses to multiple stressors intruding into their homes: noise, light, odour, and vibration.

    PubMed

    Pedersen, Eja

    2015-03-18

    Urban densification increases exposure to noise, light, odour, and vibration in urban dwellings. Exposure from combined environmental stressors intruding into the home could increase the risk of adverse effects on wellbeing, even when the exposure is at a relatively low level. This study assesses the prevalence of annoyance with a combination of potential environmental stressors common in urban areas and the association with wellbeing. A questionnaire was sent by mail to residents in five areas in Halmstad (Sweden) with similar socioeconomic and housing characteristics but different exposure (response rate 56%; n=385). Of the respondents, 50% were annoyed to some degree by at least one of the suggested stressors, most commonly by noise and vibration from local traffic. Structural equation modelling showed that annoyance led to lowered quality of life via the mediating construct residential satisfaction, which in turn was influenced by place attachment and perceived restoration possibilities in the dwelling. Stress had a negative impact on quality of life, but was not directly correlated to annoyance. Stress was however correlated with sensitivity. The findings suggest that dose-response relationships for environmental stressors should be studied in a broader context of environmental and individual factors. Also relatively low levels of exposure should be mitigated, especially if several stressors are present.

  14. City Dweller Responses to Multiple Stressors Intruding into Their Homes: Noise, Light, Odour, and Vibration

    PubMed Central

    Pedersen, Eja

    2015-01-01

    Urban densification increases exposure to noise, light, odour, and vibration in urban dwellings. Exposure from combined environmental stressors intruding into the home could increase the risk of adverse effects on wellbeing, even when the exposure is at a relatively low level. This study assesses the prevalence of annoyance with a combination of potential environmental stressors common in urban areas and the association with wellbeing. A questionnaire was sent by mail to residents in five areas in Halmstad (Sweden) with similar socioeconomic and housing characteristics but different exposure (response rate 56%; n = 385). Of the respondents, 50% were annoyed to some degree by at least one of the suggested stressors, most commonly by noise and vibration from local traffic. Structural equation modelling showed that annoyance led to lowered quality of life via the mediating construct residential satisfaction, which in turn was influenced by place attachment and perceived restoration possibilities in the dwelling. Stress had a negative impact on quality of life, but was not directly correlated to annoyance. Stress was however correlated with sensitivity. The findings suggest that dose-response relationships for environmental stressors should be studied in a broader context of environmental and individual factors. Also relatively low levels of exposure should be mitigated, especially if several stressors are present. PMID:25794188

  15. Odour cues from suitors' nests determine mating success in a fish.

    PubMed

    Lehtonen, Topi K; Kvarnemo, Charlotta

    2015-05-01

    Animals use a range of sensory cues for finding food, avoiding predators and choosing mates. In this regard, the aquatic environment is particularly suitable for the use of olfactory and other chemical cues. Nevertheless, mate choice research, even on aquatic organisms, has focused on visual signals, while chemical cues relevant in sexual selection have been assumed to be 'intrinsic' excretions of mate candidates. Here, using the sand goby Pomatoschistus minutus, a small fish with paternal egg care, we investigated the possibility that 'extrinsic' chemical cues in the males' nests could also have a significant contribution to mating success. We found that females strongly avoided laying eggs into nests subject to the odour of Saprolegnia water moulds (an egg infection) and that this effect was independent of the females' initial, visually based preference for males. To the best of our knowledge, this is the first study to show that chemical cues related to parental failure can play a large role in sexual selection. PMID:25948566

  16. Male mammals respond to a risk of sperm competition conveyed by odours of conspecific males

    NASA Astrophysics Data System (ADS)

    delBarco-Trillo, Javier; Ferkin, Michael H.

    2004-09-01

    Sperm competition occurs when a female copulates with two or more males and the sperm of those males compete within the female's reproductive tract to fertilize her eggs. The frequent occurrence of sperm competition has forced males of many species to develop different strategies to overcome the sperm of competing males. A prevalent strategy is for males to increase their sperm investment (total number of sperm allocated by a male to a particular female) after detecting a risk of sperm competition. It has been shown that the proportion of sperm that one male contributes to the sperm pool of a female is correlated with the proportion of offspring sired by that male. Therefore, by increasing his sperm investment a male may bias a potential sperm competition in his favour. Here we show that male meadow voles, Microtus pennsylvanicus, increase their sperm investment when they mate in the presence of another male's odours. Such an increase in sperm investment does not occur by augmenting the frequency of ejaculations, but by increasing the amount of sperm in a similar number of ejaculations.

  17. Dispersion of odour: a case study with a municipal solid waste landfill site in North London, United Kingdom.

    PubMed

    Sarkar, Ujjaini; Hobbs, Stephen E; Longhurst, Philip

    2003-06-01

    Municipal solid waste (MSW) landfills are a potential source of offensive odours that can create annoyance within communities. Dispersion modelling was used to quantify the potential odour strength causing an impact on the community around a particular MSW landfill site north of the London area in the United Kingdom. The case studies were completed with the short-term mode of COMPLEX-I, software developed by the US-EPA. The year 1998 was chosen as a source of baseline data. It was observed that by 2004, when the landfill will progress towards the west and a big band of the area towards the north would be partly/fully restored, the maximum contribution of the new sources giving higher odour concentrations would be in the southwesterly regions away from the landfill. Concentrations as high as 25.0 ou(E)/m(3) were observed with 3 min averaging time in the southwesterly areas as compared to concentrations of 20.0 ou(E)/m(3) at 10 min averaging times. However, the percentage frequency of such critical events occurring would be low. All other surrounding farms and small villages would be exposed to the concentration of 3.0 ou(E)/m(3) on certain occasions. In the year 2008, the majority of the filling fronts would be filled with wastes with no contributions from the active and operational cells. The maximum odour concentration around the landfill site for 1 h averaging time would be approximately 3 ou(E)/m(3) about 1.0 km north and 500 m west of the landfill site. For 3 min averaging time, the stretch of 5 ou(E)/m(3) band would be up to 2.5 km towards the north of the landfill site. It is argued that further analysis of the model calculations considering effects of wind direction, frequency of wind direction, stability of the atmosphere, selected odour threshold, integration time of the model, etc. would form a basis for calculating the separation distances of the landfill site from the surrounding community. PMID:12781755

  18. Chemical induction in mangrove crab megalopae, Ucides cordatus (Ucididae): Do young recruits emit metamorphosis-triggering odours as do conspecific adults?

    NASA Astrophysics Data System (ADS)

    Simith, Darlan de Jesus de Brito; Abrunhosa, Fernando Araújo; Diele, Karen

    2013-10-01

    In many brachyuran species, including the mangrove crab Ucides cordatus, water-soluble chemicals (odours) emitted by adult residents trigger metamorphosis of megalopae, probably facilitating habitat selection and settlement near conspecific crab population. New field findings revealed that early benthic crab stages co-inhabit burrows of both juveniles and adults of U. cordatus which raised the question whether megalopae are also stimulated by sexually immature juveniles. Therefore, we tested in an experimental laboratory study the hypothesis that small benthic recruits and older juveniles also emit metamorphosis-stimulating odours as do conspecific adult crabs. U. cordatus megalopae were cultivated in eight conspecific odour-treatments containing seawater previously conditioned with crabs of different carapace widths (CW 0.15-5.0 cm) and in a control treatment with filtered seawater not conditioned with crabs. In all odour-treatments, including those with small immature crabs, the percentage of metamorphosed larvae was significantly higher (≥74%) and the average development was shorter (15.8-19.3 days) than in the control group, where only 30% moulted after 25.6 ± 6.6 days of megalopal development. In addition, megalopae developed 2.7 days faster when exposed to odours from young and older juveniles compared to those larvae kept in contact with odours from conspecific adults. Our results clearly demonstrate that the emission of metamorphic odours in U. cordatus is independent of size/age or sexual maturity. The responsiveness of megalopae to chemicals emitted by resident crabs of varying ages should aid the natural recovery of U. cordatus populations in areas significantly affected by size-selective fishery where only large conspecific adults are harvested.

  19. Psychoacoustic abilities as predictors of vocal emotion recognition.

    PubMed

    Globerson, Eitan; Amir, Noam; Golan, Ofer; Kishon-Rabin, Liat; Lavidor, Michal

    2013-11-01

    Prosodic attributes of speech, such as intonation, influence our ability to recognize, comprehend, and produce affect, as well as semantic and pragmatic meaning, in vocal utterances. The present study examines associations between auditory perceptual abilities and the perception of prosody, both pragmatic and affective. This association has not been previously examined. Ninety-seven participants (49 female and 48 male participants) with normal hearing thresholds took part in two experiments, involving both prosody recognition and psychoacoustic tasks. The prosody recognition tasks included a vocal emotion recognition task and a focus perception task requiring recognition of an accented word in a spoken sentence. The psychoacoustic tasks included a task requiring pitch discrimination and three tasks also requiring pitch direction (i.e., high/low, rising/falling, changing/steady pitch). Results demonstrate that psychoacoustic thresholds can predict 31% and 38% of affective and pragmatic prosody recognition scores, respectively. Psychoacoustic tasks requiring pitch direction recognition were the only significant predictors of prosody recognition scores. These findings contribute to a better understanding of the mechanisms underlying prosody recognition and may have an impact on the assessment and rehabilitation of individuals suffering from deficient prosodic perception.

  20. A garlic substance disrupts odorant-binding protein recognition of insect pheromones released from adults of the angoumois grain moth, Sitotroga cerealella (Lepidoptera: Gelechiidae).

    PubMed

    Ma, M; Chang, M-M; Lei, C-L; Yang, F-L

    2016-10-01

    The angoumois grain moth, Sitotroga cerealella, is one of the most serious stored-grain pests worldwide. Control of this moth may be achieved by interfering with olfactory pathways to disrupt male-female communication with sex pheromones, using plant volatiles like garlic or its active substances. Here, three odorant-binding protein (OBP) genes [namely Si. cerealella general OBP 1 (ScerGOBP1), ScerGOBP2 and Si. cerealella pheromone-binding protein (ScerPBP)] were cloned from Si. cerealella antennae, and quantitative real-time PCR showed that these genes were predominantly expressed in adult antennae. ScerPBP expression was male-biased, but ScerGOBP1 and ScerGOBP2 were similar between sexes. The results of competitive binding assays indicated that a garlic substance, diallyl trisulphide (DATS), had similar or even higher binding affinity to ScerPBP than Si. cerealella sex pheromone, 7Z, 11E-hexadecadien-1-ol acetate (HDA). In olfactometer bioassays, DATS significantly reduced the response of adults to HDA when they were exposed to air filled with HDA and DATS. Surprisingly, ScerGOBP2, which is postulated to be involved in the detection of general odours, displayed higher affinity with HDA than did ScerPBP, indicating that ScerGOBP2 may also have a role in pheromone perception. These data suggest that DATS may interfere with recognition of female-produced sex pheromone, disrupting female and male mating behaviour and resulting in a new idea for controlling stored grain pests. PMID:27111111

  1. Effect of whey protein concentrate and sodium chloride concentrations on the odour profile of sous vide cooked whole-muscle beef from Argentina.

    PubMed

    Grigioni, G; Langman, L; Szerman, N; Irurueta, M; Vaudagna, S R

    2008-07-01

    Semitendinosus muscles added with whey protein concentrate (WPC) and sodium chloride (NaCl) were submitted to sous vide cooking. Four enhancement treatments and a control were tested: 0.875% WPC (w/w)+0.625% NaCl, 2.625% WPC+0.625% NaCl, 0.875% WPC+1.875% NaCl, 2.625% WPC+1.875% NaCl, and control (non-injected muscles). Odour analyses were carried out with an electronic nose (EN) system. EN data were evaluated applying Principal Component Analysis, Linear Discriminant Analysis and Partial Least Squares algorithm. EN was able to discriminate the odour profiles of cooked enhanced beef as a function of the amount of WPC added. No significant differences in odour profiles were observed regarding NaCl concentration. These results agreed with those obtained when odour profiles were analysed in WPC dispersions. The reported results support the applicability of EN methodology for analysing the impact of processing parameters on beef odour profiles. PMID:22062918

  2. A simple behaviour provides accuracy and flexibility in odour plume tracking--the robotic control of sensory-motor coupling in silkmoths.

    PubMed

    Ando, Noriyasu; Kanzaki, Ryohei

    2015-12-01

    Odour plume tracking is an essential behaviour for animal survival. A fundamental strategy for this is to move upstream and then across-stream. Male silkmoths, Bombyx mori, display this strategy as a pre-programmed sequential behaviour. They walk forward (surge) in response to the female sex pheromone and perform a zigzagging 'mating dance'. Though pre-programmed, the surge direction is modulated by bilateral olfactory input and optic flow. However, the nature of the interaction between these two sensory modalities and contribution of the resultant motor command to localizing an odour source are still unknown. We evaluated the ability of the silkmoth to localize an odour source under conditions of disturbed sensory-motor coupling, using a silkmoth-driven mobile robot. The significance of the bilateral olfaction of the moth was confirmed by inverting the olfactory input to the antennae, or its motor output. Inversion of the motor output induced consecutive circling, which was inhibited by covering the visual field of the moth. This suggests that the corollary discharge from the motor command and the reafference of self-generated optic flow generate compensatory signals to guide the surge accurately. Additionally, after inverting the olfactory input, the robot successfully tracked the odour plume by using a combination of behaviours. These results indicate that accurate guidance of the reflexive surge by integrating bilateral olfactory and visual information with innate pre-programmed behaviours increases the flexibility to track an odour plume even under disturbed circumstances. PMID:26486361

  3. Effect of whey protein concentrate and sodium chloride concentrations on the odour profile of sous vide cooked whole-muscle beef from Argentina.

    PubMed

    Grigioni, G; Langman, L; Szerman, N; Irurueta, M; Vaudagna, S R

    2008-07-01

    Semitendinosus muscles added with whey protein concentrate (WPC) and sodium chloride (NaCl) were submitted to sous vide cooking. Four enhancement treatments and a control were tested: 0.875% WPC (w/w)+0.625% NaCl, 2.625% WPC+0.625% NaCl, 0.875% WPC+1.875% NaCl, 2.625% WPC+1.875% NaCl, and control (non-injected muscles). Odour analyses were carried out with an electronic nose (EN) system. EN data were evaluated applying Principal Component Analysis, Linear Discriminant Analysis and Partial Least Squares algorithm. EN was able to discriminate the odour profiles of cooked enhanced beef as a function of the amount of WPC added. No significant differences in odour profiles were observed regarding NaCl concentration. These results agreed with those obtained when odour profiles were analysed in WPC dispersions. The reported results support the applicability of EN methodology for analysing the impact of processing parameters on beef odour profiles.

  4. Guatemalan potato moth Tecia solanivora distinguish odour profiles from qualitatively different potatoes Solanum tuberosum L.

    PubMed

    Karlsson, Miriam Frida; Birgersson, Göran; Witzgall, Peter; Lekfeldt, Jonas Duus Stevens; Nimal Punyasiri, P A; Bengtsson, Marie

    2013-01-01

    Guatemalan potato moth, Tecia solanivora, lay eggs in the soil nearby potato Solanum spp. and larvae feed on the tubers. We investigated the oviposition behaviour of T. solanivora females and the survival of larval offspring on healthy vs. stressed, i.e. light exposed and/or damaged potato tubers. In choice tests, females laid significantly more eggs in response to potato odour of healthy tubers and female oviposition preference correlated with higher larval survival. Survival of larvae was negatively correlated with the tuber content of the steroid glycoalkaloids α-solanine and α-chaconine: healthy potatoes contained lower amounts than stressed tubers, ranging from 25 to 500 μg g⁻¹ and from 30 to 600 μg g⁻¹, respectively. Analysis of volatile compounds emitted by potato tubers revealed that stressed tubers could clearly be distinguished from healthy tubers by the composition of their volatile profiles. Compounds that contributed to this difference were e.g. decanal, nonanal, isopropyl myristate, phenylacetaldehyde, benzothiazole, heptadecane, octadecane, myristicin, E,E-α-farnesene and verbenone. Oviposition assays, when female moths were not in contact with the tubers, clearly demonstrated that volatiles guide the females to lay fewer eggs on stressed tubers that are of inferior quality for the larvae. We propose that volatiles, such as sesquiterpenes and aldehydes, mediate oviposition behaviour and are correlated with biosynthetically related, non-volatile compounds, such as steroidal glycoalkaloids, which influence larval survival. We conclude that the oviposition response and larval survival of T. solanivora on healthy vs. stressed tubers supports the preference performance hypothesis for insect herbivores.

  5. Perception of biological motion in visual agnosia.

    PubMed

    Huberle, Elisabeth; Rupek, Paul; Lappe, Markus; Karnath, Hans-Otto

    2012-01-01

    Over the past 25 years, visual processing has been discussed in the context of the dual stream hypothesis consisting of a ventral ("what") and a dorsal ("where") visual information processing pathway. Patients with brain damage of the ventral pathway typically present with signs of visual agnosia, the inability to identify and discriminate objects by visual exploration, but show normal perception of motion perception. A dissociation between the perception of biological motion and non-biological motion has been suggested: perception of biological motion might be impaired when "non-biological" motion perception is intact and vice versa. The impact of object recognition on the perception of biological motion remains unclear. We thus investigated this question in a patient with severe visual agnosia, who showed normal perception of non-biological motion. The data suggested that the patient's perception of biological motion remained largely intact. However, when tested with objects constructed of coherently moving dots ("Shape-from-Motion"), recognition was severely impaired. The results are discussed in the context of possible mechanisms of biological motion perception.

  6. Relations among early object recognition skills: Objects and letters

    PubMed Central

    Augustine, Elaine; Jones, Susan S.; Smith, Linda B.; Longfield, Erica

    2014-01-01

    Human visual object recognition is multifaceted, with several domains of expertise. Developmental relations between young children's letter recognition and their 3-dimensional object recognition abilities are implicated on several grounds but have received little research attention. Here, we ask how preschoolers’ success in recognizing letters relates to their ability to recognize 3-dimensional objects from sparse shape information alone. A relation is predicted because perception of the spatial relations is critical in both domains. Seventy-three 2 ½- to 4-year-old children completed a Letter Recognition task, measuring the ability to identify a named letter among 3 letters with similar shapes, and a “Shape Caricature Recognition” task, measuring recognition of familiar objects from sparse, abstract information about their part shapes and the spatial relations among those parts. Children also completed a control “Shape Bias” task, in which success depends on recognition of overall object shape but not of relational structure. Children's success in letter recognition was positively related to their shape caricature recognition scores, but not to their shape bias scores. The results suggest that letter recognition builds upon developing skills in attending to and representing the relational structure of object shape, and that these skills are common to both 2-dimensional and 3-dimensional object perception. PMID:25969673

  7. The Swipe Card Model of Odorant Recognition

    PubMed Central

    Brookes, Jennifer C.; Horsfield, Andrew P.; Stoneham, A. Marshall

    2012-01-01

    Just how we discriminate between the different odours we encounter is not completely understood yet. While obviously a matter involving biology, the core issue is a matter for physics: what microscopic interactions enable the receptors in our noses-small protein switches—to distinguish scent molecules? We survey what is and is not known about the physical processes that take place when we smell things, highlighting the difficulties in developing a full understanding of the mechanics of odorant recognition. The main current theories, discussed here, fall into two major groups. One class emphasises the scent molecule's shape, and is described informally as a “lock and key” mechanism. But there is another category, which we focus on and which we call “swipe card” theories: the molecular shape must be good enough, but the information that identifies the smell involves other factors. One clearly-defined “swipe card” mechanism that we discuss here is Turin's theory, in which inelastic electron tunnelling is used to discern olfactant vibration frequencies. This theory is explicitly quantal, since it requires the molecular vibrations to take in or give out energy only in discrete quanta. These ideas lead to obvious experimental tests and challenges. We describe the current theory in a form that takes into account molecular shape as well as olfactant vibrations. It emerges that this theory can explain many observations hard to reconcile in other ways. There are still some important gaps in a comprehensive physics-based description of the central steps in odorant recognition. We also discuss how far these ideas carry over to analogous processes involving other small biomolecules, like hormones, steroids and neurotransmitters. We conclude with a discussion of possible quantum behaviours in biology more generally, the case of olfaction being just one example. This paper is presented in honour of Prof. Marshall Stoneham who passed away unexpectedly during its

  8. The swipe card model of odorant recognition.

    PubMed

    Brookes, Jennifer C; Horsfield, Andrew P; Stoneham, A Marshall

    2012-01-01

    Just how we discriminate between the different odours we encounter is not completely understood yet. While obviously a matter involving biology, the core issue isa matter for physics: what microscopic interactions enable the receptors in our noses-small protein switches—to distinguish scent molecules? We survey what is and is not known about the physical processes that take place when we smell things, highlighting the difficulties in developing a full understanding of the mechanics of odorant recognition. The main current theories, discussed here, fall into two major groups. One class emphasises the scent molecule's shape, and is described informally as a "lock and key" mechanism. But there is another category, which we focus on and which we call "swipe card" theories:the molecular shape must be good enough, but the information that identifies the smell involves other factors. One clearly-defined "swipe card" mechanism that we discuss here is Turin's theory, in which inelastic electron tunnelling is used to discern olfactant vibration frequencies. This theory is explicitly quantal, since it requires the molecular vibrations to take in or give out energy only in discrete quanta. These ideas lead to obvious experimental tests and challenges. We describe the current theory in a form that takes into account molecular shape as well as olfactant vibrations. It emerges that this theory can explain many observations hard to reconcile in other ways. There are still some important gaps in a comprehensive physics-based description of the central steps in odorant recognition. We also discuss how far these ideas carry over to analogous processes involving other small biomolecules, like hormones, steroids and neurotransmitters. We conclude with a discussion of possible quantum behaviours in biology more generally, the case of olfaction being just one example. This paper is presented in honour of Prof. Marshall Stoneham who passed away unexpectedly during its writing. PMID

  9. Voice input/output capabilities at Perception Technology Corporation

    NASA Technical Reports Server (NTRS)

    Ferber, Leon A.

    1977-01-01

    Condensed resumes of key company personnel at the Perception Technology Corporation are presented. The staff possesses recognition, speech synthesis, speaker authentication, and language identification. Hardware and software engineers' capabilities are included.

  10. Social hackers: integration in the host chemical recognition system by a paper wasp social parasite.

    PubMed

    Turillazzi, S; Sledge, M F; Dani, F R; Cervo, R; Massolo, A; Fondelli, L

    2000-04-01

    Obligate social parasites in the social insects have lost the worker caste and the ability to establish nests. As a result, parasites must usurp a host nest, overcome the host recognition system, and depend on the host workers to rear their offspring. We analysed cuticular hydrocarbon profiles of live parasite females of the paper wasp social parasite Polistes sulcifer before and after usurpation of host nests, using the non-destructive technique of solid-phase micro-extraction. Our results reveal that hydrocarbon profiles of parasites change after usurpation of host nests to match the cuticular profile of the host species. Chemical evidence further shows that the parasite queen changes the odour of the nest by the addition of a parasite-specific hydrocarbon. We discuss the possible role of this in the recognition and acceptance of the parasite and its offspring in the host colony.

  11. Social Hackers: Integration in the Host Chemical Recognition System by a Paper Wasp Social Parasite

    NASA Astrophysics Data System (ADS)

    Turillazzi, S.; Sledge, M. F.; Dani, F. R.; Cervo, R.; Massolo, A.; Fondelli, L.

    Obligate social parasites in the social insects have lost the worker caste and the ability to establish nests. As a result, parasites must usurp a host nest, overcome the host recognition system, and depend on the host workers to rear their offspring. We analysed cuticular hydrocarbon profiles of live parasite females of the paper wasp social parasite Polistes sulcifer before and after usurpation of host nests, using the non-destructive technique of solid-phase micro-extraction. Our results reveal that hydrocarbon profiles of parasites change after usurpation of host nests to match the cuticular profile of the host species. Chemical evidence further shows that the parasite queen changes the odour of the nest by the addition of a parasite-specific hydrocarbon. We discuss the possible role of this in the recognition and acceptance of the parasite and its offspring in the host colony.

  12. Ability of predator odour exposure to elicit conditioned versus sensitised post traumatic stress disorder-like behaviours, and forebrain deltaFosB expression, in rats.

    PubMed

    Mackenzie, L; Nalivaiko, E; Beig, M I; Day, T A; Walker, F R

    2010-08-25

    At present, exposure of a rodent to the odour of a predator is one of the most common animal models of post traumatic stress disorder (PTSD). Despite this, the model remains incompletely characterized, particularly in regard to within subject assessment of major PTSD-like behaviours. In an attempt to redress this situation, we have extensively characterized the two broad categories of behaviour that are considered to characterize PTSD, that is sensitized behaviours such as social withdrawal and hypervigilance and conditioned behaviours such as avoidance of trauma linked cues. Specifically, we determined the presence and duration of both conditioned and sensitized behaviours, in the same cohort of animals, after three exposures to predator odour. Conditioned fear was assessed on the basis of inhibition of locomotor activity upon return to context 2, 7, 14, 21, and 28 days after the last odour exposure session. To assess the impact on sensitization behaviours, we monitored acoustic startle responses and social interaction behaviour 4, 9, 16, 23, and 30 days after the last exposure session. In addition to examining the behavioural consequences associated with odour exposure, we also determined the key brain regions that were activated using DeltaFosB immunohistochemistry. Our results show that the two groups of behaviours thought to characterize PTSD (conditioned and sensitized) do not travel together in the predator odour model, with clear evidence of enduring changes in conditioned fear but little evidence of changes in social interaction or acoustic startle. With regard to associated patterns of activity in the brain, we observed that odour-exposed animals exhibited significantly higher numbers of FosB-positive nuclei in only the medial prefrontal cortex (mPFC), a finding that can be viewed as being consistent with the observed behavioural changes. PMID:20478366

  13. A "Situational" and "Coorientational" Measure of Specialized Magazine Editors' Perceptions of Readers.

    ERIC Educational Resources Information Center

    Jeffers, Dennis W.

    A study was undertaken of specialized magazine editors' perceptions of audience characteristics as well as the perceived role of their publications. Specifically, the study examines the relationship between the editors' perceptions of reader problem recognition, level of involvement, constraint recognition, and possession of reference criteria and…

  14. Facial expression recognition in Williams syndrome.

    PubMed

    Gagliardi, Chiara; Frigerio, Elisa; Burt, D Michael; Cazzaniga, Ilaria; Perrett, David I; Borgatti, Renato

    2003-01-01

    Individuals with Williams syndrome (WS) excel in face recognition and show both a remarkable concern for social stimuli and a linguistic capacity for, in particular, emotionally referenced language. The animated full facial expression comprehension test (AFFECT), a new test of emotional expression perception, was used to compare participants with WS with both chronological and mental age-matched controls. It was found that expression recognition in WS was worse than that of chronologically age-matched controls but indistinguishable from that of mental age controls. Different processing strategies are thought to underlie the similar performance of individuals with WS and mental age controls. The expression recognition performance of individuals with WS did not correlate with age, but was instead found to correlate with IQ. This is compared to earlier findings, replicated here, that face recognition performance on the Benton test correlates with age and not IQ. The results of the Benton test have been explained in terms of individuals with WS being good at face recognition; since a piecemeal strategy can be used, this strategy is improved with practice which would explain the correlation with age. We propose that poor expression recognition of the individuals with WS is due to a lack of configural ability since changes in the configuration of the face are an important part of expressions. Furthermore, these reduced configural abilities may be due to abnormal neuronal development and are thus fixed from an early age. PMID:12591030

  15. Social cichlid fish change behaviour in response to a visual predator stimulus, but not the odour of damaged conspecifics.

    PubMed

    O'Connor, Constance M; Reddon, Adam R; Odetunde, Aderinsola; Jindal, Shagun; Balshine, Sigal

    2015-12-01

    Predation is one of the primary drivers of fitness for prey species. Therefore, there should be strong selection for accurate assessment of predation risk, and whenever possible, individuals should use all available information to fine-tune their response to the current threat of predation. Here, we used a controlled laboratory experiment to assess the responses of individual Neolamprologus pulcher, a social cichlid fish, to a live predator stimulus, to the odour of damaged conspecifics, or to both indicators of predation risk combined. We found that fish in the presence of the visual predator stimulus showed typical antipredator behaviour. Namely, these fish decreased activity and exploration, spent more time seeking shelter, and more time near conspecifics. Surprisingly, there was no effect of the chemical cue alone, and fish showed a reduced response to the combination of the visual predator stimulus and the odour of damaged conspecifics relative to the visual predator stimulus alone. These results demonstrate that N. pulcher adjust their anti-predator behaviour to the information available about current predation risk, and we suggest a possible role for the use of social information in the assessment of predation risk in a cooperatively breeding fish. PMID:26467942

  16. Location of and landing on a source of human body odour by female Culex quinquefasciatus in still and moving air

    PubMed Central

    LACEY, EMERSON S.; CARDÉ, RING T.

    2014-01-01

    The orientation to and landing on a source of human odour by female Culex quinquefasciatus Say (Diptera: Culicidae) is observed in a wind tunnel without an airflow or with a laminar airflow of 0.2 m s-1. Odours from human feet are collected by ‘wearing’ clean glass beads inside a stocking and presenting beads in a Petri dish in a wind tunnel. Mosquitoes are activated by brief exposure to a 1 L min-1 jet of 4% CO2 positioned 10 cm from the release cage. In moving air at 0.2 m s-1, a mean of 3.45 ± 0.49 landings are observed in 10 min trials (5 mosquitoes per trial), whereas 6.50 ± 0.96 landings are recorded in still air. Furthermore, 1.45 ± 0.31mosquitoes are recorded on beads at any one time in moving air (a measure of individuals landing versus one landing multiple times) compared to 3.10 ± 0.31 in still air. Upwind flight to beads in moving air is demonstrated by angular headings of flight immediately prior to landing, whereas approaches to beads in still air are oriented randomly. The mean latency until first landing is 226.7 ± 17.98 s in moving air compared to 122.5 ± 24.18 in still air. Strategies used to locate a prospective host at close range in still air are considered. PMID:26472918

  17. UV-based advanced oxidation processes for the treatment of odour compounds: efficiency and by-product formation.

    PubMed

    Zoschke, Kristin; Dietrich, Norman; Börnick, Hilmar; Worch, Eckhard

    2012-10-15

    The occurrence of the taste and odour compounds geosmin and 2-methyl isoborneol (2-MIB) affects the organoleptic quality of raw waters from drinking water reservoirs worldwide. UV-based oxidation processes for the removal of these substances are an alternative to adsorption and biological processes, since they additionally provide disinfection of the raw water. We could show that the concentration of geosmin and 2-MIB could be reduced by VUV irradiation and the combination of UV irradiation with ozone and hydrogen peroxide in pure water and water from a drinking water reservoir. The figure of merit EE/O is an appropriate tool to compare the AOPs and showed that VUV and UV/O(3) yielded the lowest treatment costs for the odour compounds in pure and raw water, respectively. Additionally, VUV irradiation with addition of ozone, generated by the VUV lamp, was evaluated. The generation of ozone and the irradiation were performed in a single reactor system using the same low-pressure mercury lamp, thereby reducing the energy consumption of the treatment process. The formation of the undesired by-products nitrite and bromate was investigated. The combination of VUV irradiation with ozone produced by a VUV lamp avoided the formation of relevant concentrations of the by-products. The internal generation of ozone is capable to produce ozone concentrations sufficient to reduce EE/O below 1 kWh m(-3) and without the risk of the formation of nitrite or bromate above the maximum contaminant level.

  18. Deadly intentions: naïve introduced foxes show rapid attraction to odour cues of an unfamiliar native prey

    PubMed Central

    Bytheway, Jenna P.; Price, Catherine J.; Banks, Peter B.

    2016-01-01

    Introduced predators have caused declines and extinctions of native species worldwide, seemingly able to find and hunt new, unfamiliar prey from the time of their introduction. Yet, just as native species are often naïve to introduced predators, in theory, introduced predators should initially be naïve in their response to novel native prey. Here we examine the response of free-living introduced red foxes (Vulpes vulpes) to their first encounter with the odour cues of a novel native prey, the long-nosed bandicoot (Perameles nasuta). Despite no experience with bandicoots at the study site, foxes were significantly more interested in bandicoot odour compared to untreated controls and to a co-evolved prey, the black rat (Rattus rattus). So what gives introduced predators a novelty advantage over native prey? Such neophilia towards novel potential food sources carries little costs, however naïve native prey often lack analogous neophobic responses towards novel predators, possibly because predator avoidance is so costly. We propose that this nexus between the costs and benefits of responding to novel information is different for alien predators and native prey, giving alien predators a novelty advantage over native prey. This may explain why some introduced predators have rapid and devastating impacts on native fauna. PMID:27416966

  19. Deadly intentions: naïve introduced foxes show rapid attraction to odour cues of an unfamiliar native prey.

    PubMed

    Bytheway, Jenna P; Price, Catherine J; Banks, Peter B

    2016-01-01

    Introduced predators have caused declines and extinctions of native species worldwide, seemingly able to find and hunt new, unfamiliar prey from the time of their introduction. Yet, just as native species are often naïve to introduced predators, in theory, introduced predators should initially be naïve in their response to novel native prey. Here we examine the response of free-living introduced red foxes (Vulpes vulpes) to their first encounter with the odour cues of a novel native prey, the long-nosed bandicoot (Perameles nasuta). Despite no experience with bandicoots at the study site, foxes were significantly more interested in bandicoot odour compared to untreated controls and to a co-evolved prey, the black rat (Rattus rattus). So what gives introduced predators a novelty advantage over native prey? Such neophilia towards novel potential food sources carries little costs, however naïve native prey often lack analogous neophobic responses towards novel predators, possibly because predator avoidance is so costly. We propose that this nexus between the costs and benefits of responding to novel information is different for alien predators and native prey, giving alien predators a novelty advantage over native prey. This may explain why some introduced predators have rapid and devastating impacts on native fauna. PMID:27416966

  20. Social cichlid fish change behaviour in response to a visual predator stimulus, but not the odour of damaged conspecifics.

    PubMed

    O'Connor, Constance M; Reddon, Adam R; Odetunde, Aderinsola; Jindal, Shagun; Balshine, Sigal

    2015-12-01

    Predation is one of the primary drivers of fitness for prey species. Therefore, there should be strong selection for accurate assessment of predation risk, and whenever possible, individuals should use all available information to fine-tune their response to the current threat of predation. Here, we used a controlled laboratory experiment to assess the responses of individual Neolamprologus pulcher, a social cichlid fish, to a live predator stimulus, to the odour of damaged conspecifics, or to both indicators of predation risk combined. We found that fish in the presence of the visual predator stimulus showed typical antipredator behaviour. Namely, these fish decreased activity and exploration, spent more time seeking shelter, and more time near conspecifics. Surprisingly, there was no effect of the chemical cue alone, and fish showed a reduced response to the combination of the visual predator stimulus and the odour of damaged conspecifics relative to the visual predator stimulus alone. These results demonstrate that N. pulcher adjust their anti-predator behaviour to the information available about current predation risk, and we suggest a possible role for the use of social information in the assessment of predation risk in a cooperatively breeding fish.

  1. Face recognition increases during saccade preparation.

    PubMed

    Lin, Hai; Rizak, Joshua D; Ma, Yuan-ye; Yang, Shang-chuan; Chen, Lin; Hu, Xin-tian

    2014-01-01

    Face perception is integral to human perception system as it underlies social interactions. Saccadic eye movements are frequently made to bring interesting visual information, such as faces, onto the fovea for detailed processing. Just before eye movement onset, the processing of some basic features, such as the orientation, of an object improves at the saccade landing point. Interestingly, there is also evidence that indicates faces are processed in early visual processing stages similar to basic features. However, it is not known whether this early enhancement of processing includes face recognition. In this study, three experiments were performed to map the timing of face presentation to the beginning of the eye movement in order to evaluate pre-saccadic face recognition. Faces were found to be similarly processed as simple objects immediately prior to saccadic movements. Starting ∼ 120 ms before a saccade to a target face, independent of whether or not the face was surrounded by other faces, the face recognition gradually improved and the critical spacing of the crowding decreased as saccade onset was approaching. These results suggest that an upcoming saccade prepares the visual system for new information about faces at the saccade landing site and may reduce the background in a crowd to target the intended face. This indicates an important role of pre-saccadic eye movement signals in human face recognition.

  2. Building Group Recognition.

    ERIC Educational Resources Information Center

    Chartier, George

    1994-01-01

    Discusses the value of name recognition for theater companies. Describes steps toward identity and recognition, analyzing the group, the mission statement, symbolic logic, designing and identity, developing a communications plan, and meaningful activities. (SR)

  3. Speech recognition and understanding

    SciTech Connect

    Vintsyuk, T.K.

    1983-05-01

    This article discusses the automatic processing of speech signals with the aim of finding a sequence of works (speech recognition) or a concept (speech understanding) being transmitted by the speech signal. The goal of the research is to develop an automatic typewriter that will automatically edit and type text under voice control. A dynamic programming method is proposed in which all possible class signals are stored, after which the presented signal is compared to all the stored signals during the recognition phase. Topics considered include element-by-element recognition of words of speech, learning speech recognition, phoneme-by-phoneme speech recognition, the recognition of connected speech, understanding connected speech, and prospects for designing speech recognition and understanding systems. An application of the composition dynamic programming method for the solution of basic problems in the recognition and understanding of speech is presented.

  4. Profiles of Discourse Recognition

    ERIC Educational Resources Information Center

    Singer, Murray

    2013-01-01

    A discourse recognition theory derived from more general memory formulations would be broad in its psychological implications. This study compared discourse recognition with some established profiles of item recognition. Participants read 10 stories either once or twice each. They then rated their confidence in recognizing explicit, paraphrased,…

  5. Changing Perceptions

    ERIC Educational Resources Information Center

    Mallett, Susanne; Wren, Steve; Dawes, Mark; Blinco, Amy; Haines, Brett; Everton, Jenny; Morgan, Ellen; Barton, Craig; Breen, Debbie; Ellison, Geraldine; Burgess, Danny; Stavrou, Jim; Carre, Catherine; Watson, Fran; Cherry, David; Hawkins, Chris; Stapenhill-Hunt, Maria; Gilderdale, Charlie; Kiddle, Alison; Piggott, Jennifer

    2009-01-01

    A group of teachers involved in embedding NRICH tasks (http://nrich.maths.org) into their everyday practice were keen to challenge common perceptions of mathematics, and of the teaching and learning of mathematics. In this article, the teachers share what they are doing to change these perceptions in their schools.

  6. Brief Report: Attention Effect on a Measure of Social Perception

    ERIC Educational Resources Information Center

    Fine, Jodene Goldenring; Semrud-Clikeman, Margaret; Butcher, Brianne; Walkowiak, Jennifer

    2008-01-01

    A measure of social perception (CASP) was used to assess differences in social perception among typically developing children, children with autistic spectrum disorders (ASD), and children with Attention Deficit/Hyperactivity Disorder (ADHD). Significant between-group differences were found in recognition of emotions in video, with children…

  7. The Development of an Adolescent Perception of Being Known Measure

    ERIC Educational Resources Information Center

    Wallace, Tanner LeBaron; Ye, Feifei; McHugh, Rebecca; Chhuon, Vichet

    2012-01-01

    Adopting a constructivist perspective of adolescent development, we argue adolescents' perceptions of "being known" reflect teachers' authentic recognition of adolescents' multiple emerging identities. As such, adolescent perceptions of being known are a distinct factor associated with high school students' engagement in school. A mixed method…

  8. Patterns of odour emission, thermogenesis and pollinator activity in cones of an African cycad: what mechanisms apply?

    PubMed Central

    Suinyuy, Terence N.; Donaldson, John S.; Johnson, Steven D.

    2013-01-01

    Background and Aims Ontogenetic patterns of odour emissions and heating associated with plant reproductive structures may have profound effects on insect behaviour, and consequently on pollination. In some cycads, notably Macrozamia, temporal changes in emission of specific odour compounds and temperature have been interpreted as a ‘push–pull’ interaction in which pollinators are either attracted or repelled according to the concentration of the emitted volatiles. To establish which mechanisms occur in the large Encephalartos cycad clade, the temporal patterns of volatile emissions, heating and pollinator activity of cones of Encephalartos villosus in the Eastern Cape (EC) and KwaZulu Natal (KZN) of South Africa were investigated. Methods and Key Results Gas chromatography–mass spectrometry (GC-MS) analyses of Encephalartos villosus cone volatiles showed that emissions, dominated by eucalyptol and 2-isopropyl-3-methoxypyrazine in EC populations and (3E)-1,3-octadiene and (3E,5Z)-1,3,5-octatriene in the KZN populations, varied across developmental stages but did not vary significantly on a daily cycle. Heating in male cones was higher at dehiscence than during pre- and post-dehiscence, and reached a maximum at about 1830 h when temperatures were between 7·0 and 12·0 °C above ambient. Daily heating of female cones was less pronounced and reached a maximum at about 1345 h when it was on average between 0·9 and 3·0 °C above ambient. Insect abundance on male cones was higher at dehiscence than at the other stages and significantly higher in the afternoon than in the morning and evening. Conclusions There are pronounced developmental changes in volatile emissions and heating in E. villosus cones, as well as strong daily changes in thermogenesis. Daily patterns of volatile emissions and pollinator abundance in E. villosus are different from those observed in some Macrozamia cycads and not consistent with the push–pull pattern as periods of peak odour

  9. The Effects of Test Difficulty Level on Undergraduates' Perception of Examination Difficulties and Their State Anxiety.

    ERIC Educational Resources Information Center

    Head, L. Quinn; Lindsey, Jimmy D.

    The effects of test difficulty on the perception of examination difficulties and state anxiety are investigated. Thirty undergraduate students were administered the Educational Psychology Recognition Test and Test Perception Inventory to assess task difficulty and perception of exam difficultness. A modified version of the State-Trait Anxiety…

  10. Effect of reuterin-producing Lactobacillus reuteri coupled with glycerol on the volatile fraction, odour and aroma of semi-hard ewe milk cheese.

    PubMed

    Gómez-Torres, Natalia; Ávila, Marta; Delgado, David; Garde, Sonia

    2016-09-01

    The effect of the biopreservation system formed by Lactobacillus reuteri INIA P572, a reuterin-producing strain, and glycerol (required for reuterin production), on the volatile fraction, aroma and odour of industrial sized semi-hard ewe milk cheese (Castellano type) was investigated over a 3-month ripening period. The volatile compounds were extracted and analyzed by SPME-GC-MS and cheese odour and aroma profiles were studied by descriptive sensory analysis. Control cheese was made only with a mesophilic starter and experimental cheeses with L. reuteri were made with and without glycerol. The addition of L. reuteri INIA P572 to milk enhanced the formation of six volatile compounds. Despite the changes in the volatile compounds profile, the use of L. reuteri INIA P572 did not noticeably affect the sensory characteristics of cheese. On the other hand, the addition of L. reuteri INIA P572 coupled with 30mM glycerol enhanced the formation of twelve volatile compounds, but decreased the formation of five ones. The use of the biopreservation system did not affect overall odour and aroma quality of cheese although it resulted in a significant decrease of the odour intensity scores. In addition, this cheese received significant higher scores for "cheesy" aroma and significant lower scores for the aroma attributes "milky", "caramel" and "yogurt-like". The first two axes of a principal component analysis (PCA) performed for selected volatile compounds and sensory characteristics, accounting for 75% of the variability between cheeses, separated cheeses made with L. reuteri INIA P572 and glycerol from the rest of cheeses, and also differentiated control cheese from cheeses made with L. reuteri INIA P572 from day 60 onward. Our results showed that the reuterin-producing L. reuteri INIA P572 strain, when coupled with glycerol, may be a suitable biopreservation system to use in cheese without affecting odour and aroma quality. PMID:27289193

  11. Effect of intramuscular fat content and serving temperature on temporal sensory perception of sliced and vacuum packaged dry-cured ham.

    PubMed

    Fuentes, Verónica; Ventanas, Jesús; Morcuende, David; Ventanas, Sonia

    2013-03-01

    The present study aimed to evaluate the influence of three serving temperatures (7 °C, 16 °C and 20 °C) and two different ham sections varying in the intramuscular fat (IMF) content on the sensory characteristics of sliced and vacuum-packaged Iberian dry-cured hams using the time-intensity (TI) method. Preceding the TI study, appearance and odour of dry-cured hams were evaluated using a descriptive profile. Fluidity and brightness of the external fat, brightness of lean and all odour attributes increased as serving temperature increased whereas the hardness of external fat decreased with temperature. Oral temperature would have disguised the effect of serving temperature over time as a consequence of a possible balance between both temperatures during samples' consumption. TI revealed that the effect of serving temperature on flavour and texture perception was more noticeable along the first seconds of chewing. Odour intensities increased with the IMF content and temporal perception of hardness, saltiness and rancid flavour were also significantly influenced by the IMF content. PMID:23273473

  12. Effect of intramuscular fat content and serving temperature on temporal sensory perception of sliced and vacuum packaged dry-cured ham.

    PubMed

    Fuentes, Verónica; Ventanas, Jesús; Morcuende, David; Ventanas, Sonia

    2013-03-01

    The present study aimed to evaluate the influence of three serving temperatures (7 °C, 16 °C and 20 °C) and two different ham sections varying in the intramuscular fat (IMF) content on the sensory characteristics of sliced and vacuum-packaged Iberian dry-cured hams using the time-intensity (TI) method. Preceding the TI study, appearance and odour of dry-cured hams were evaluated using a descriptive profile. Fluidity and brightness of the external fat, brightness of lean and all odour attributes increased as serving temperature increased whereas the hardness of external fat decreased with temperature. Oral temperature would have disguised the effect of serving temperature over time as a consequence of a possible balance between both temperatures during samples' consumption. TI revealed that the effect of serving temperature on flavour and texture perception was more noticeable along the first seconds of chewing. Odour intensities increased with the IMF content and temporal perception of hardness, saltiness and rancid flavour were also significantly influenced by the IMF content.

  13. Sequencing Visual Perception Skills. Training Manual.

    ERIC Educational Resources Information Center

    Langstaff, Anne L., Ed.

    The training manual of sequenced visual perception skills offers an assessment guide, explains approximately 20 major types of instructional activities, and describes appropriate instructional materials, illustrated in an associated filmstrip. All activities are organized into four learning steps (recognition, discrimination, recall, and…

  14. Snail odour-clouds: spreading and contribution to the transmission success of Trichobilharzia ocellata (Trematoda, Digenea) miracidia.

    PubMed

    Hertel, Jan; Holweg, Alexander; Haberl, Bernhard; Kalbe, Martin; Haas, Wilfried

    2006-02-01

    Chemical communication among freshwater organisms is an adaptation to improve their coexistence. Here,we focus on the chemical cues secreted by the freshwater gastropod Lymnaea stagnalis, which are known to stimulate behavioural responses of Trichobilharzia ocellata (Plathelminthes, Digenea, Trematoda) miracidia. Such responses are commonly claimed to influence transmission positively, but in response to chemical cues miracidia randomly change their swimming direction. This kind of response does not necessarily increase transmission, because miracidia may be trapped at the periphery of very large snail odour-clouds, which may prevent them from approaching the snail. On the other hand, the odour clouds may be too small to improve host-localisation. To shed light on these scenarios, the spreading of molecules released around L. stagnalis (active space) was visualised by recording host-finding responses of T. ocellata miracidia when they approached snails. Behavioural responses of miracidia indicated the spreading of compounds forming an attractive active space only around the host-snail L. stagnalis, but not around sympatric non-host-snail species. The active space increased approximately linearly with the time the snail rested at the same spot and within 5 min it reached a volume of more than 30 times that of the snail. We also demonstrated in a large-scale experiment, that the active space of L. stagnalis significantly increases the transmission success of T. ocellata miracidia. Additionally, the microhabitat selection of T. ocellata miracidia was studied, demonstrating that peripheral locations near the water surface were preferred, which are also preferred sites of L. stagnalis. Improved chemoperception and microhabitat selection may have been a consequence of coevolution with snails and benefited miracidia, which became efficient transmissive stages.

  15. 3-Methyl-3-sulfanylhexan-1-ol as a major descriptor for the human axilla-sweat odour profile.

    PubMed

    Troccaz, Myriam; Starkenmann, Christian; Niclass, Yvan; van de Waal, Matthijs; Clark, Anthony J

    2004-07-01

    This study sets out to redress the lack of knowledge in the area of volatile sulfur compounds (VSCs) in axillary sweat malodour. Sterile odourless underarm sweat (500 ml) was collected from 30 male volunteers after excessive sweating. Five strains of bacteria, Corynebacterium tuberculostearicum, Corynebacterium minutissimum, Staphylococcus epidermidis, Staphylococcus haemolyticus, and Bacillus licheniformis, were isolated and characterised for their ability to generate an authentic axillary odour from the sweat material collected. As expected, all of the five bacterial strains produced strong sweat odours. Surprisingly, after extensive olfactive evaluation, the strain of Staphylococcus haemolyticus produced the most sulfury sweat character. This strain was then chosen as the change agent for the 500 ml of odourless underarm sweat collected. After bacterial incubation, the 500-ml sample was further processed for GC-olfactometry (GC-O), GC/MS analysis. GC-O of an extract free of organic acids provided three zones of interest. The first was chicken-sulfury, the second zone was onion-like, and the third zone was sweat, clary sage-like. From the third zone, a new impact molecule, (R)- or (S)-3-methyl-3-sulfanylhexan-1-ol, was isolated and identified by GC/MS, MD-GC, and GC AED (atomic emission detector). (S)-3-methyl-3-sulfanylhexan-1-ol was sniff-evaluated upon elution from a chiral GC column and was described as sweat and onion-like; its opposite enantiomer, (R)-3-methyl-3-sulfanylhexan-1-ol, was described as fruity and grapefruit-like. The (S)-form was found to be the major enantiomer (75%).

  16. Sonority contours in word recognition

    NASA Astrophysics Data System (ADS)

    McLennan, Sean

    2003-04-01

    Contrary to the Generativist distinction between competence and performance which asserts that speech or perception errors are due to random, nonlinguistic factors, it seems likely that errors are principled and possibly governed by some of the same constraints as language. A preliminary investigation of errors modeled after the child's ``Chain Whisper'' game (a degraded stimulus task) suggests that a significant number of recognition errors can be characterized as an improvement in syllable sonority contour towards the linguistically least-marked, voiceless-stop-plus-vowel syllable. An independent study of sonority contours showed that approximately half of the English lexicon can be uniquely identified by their contour alone. Additionally, ``sororities'' (groups of words that share a single sonority contour), surprisingly, show no correlation to familiarity or frequency in either size or membership. Together these results imply that sonority contours may be an important factor in word recognition and in defining word ``neighborhoods.'' Moreover, they suggest that linguistic markedness constraints may be more prevalent in performance-related phenomena than previously accepted.

  17. Relations among Linguistic and Cognitive Skills and Spoken Word Recognition in Adults with Cochlear Implants

    ERIC Educational Resources Information Center

    Collison, Elizabeth A.; Munson, Benjamin; Carney, Arlene Earley

    2004-01-01

    This study examined spoken word recognition in adults with cochlear implants (CIs) to determine the extent to which linguistic and cognitive abilities predict variability in speech-perception performance. Both a traditional consonant-vowel-consonant (CVC)-repetition measure and a gated-word recognition measure (F. Grosjean, 1996) were used.…

  18. The Development of the Orthographic Consistency Effect in Speech Recognition: From Sublexical to Lexical Involvement

    ERIC Educational Resources Information Center

    Ventura, Paulo; Morais, Jose; Kolinsky, Regine

    2007-01-01

    The influence of orthography on children's on-line auditory word recognition was studied from the end of Grade 2 to the end of Grade 4, by examining the orthographic consistency effect [Ziegler, J. C., & Ferrand, L. (1998). Orthography shapes the perception of speech: The consistency effect in auditory recognition. "Psychonomic Bulletin & Review",…

  19. Researching the Use of Voice Recognition Writing Software.

    ERIC Educational Resources Information Center

    Honeycutt, Lee

    2003-01-01

    Notes that voice recognition technology (VRT) has become accurate and fast enough to be useful in a variety of writing scenarios. Contends that little is known about how this technology might affect writing process or perceptions of silent writing. Explores future use of VRT by examining past research in the technology of dictation. (PM)

  20. A bacterial tyrosine phosphatase inhibits plant pattern recognition receptor activation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perception of pathogen-associated molecular patterns (PAMPs) by surface-localised pattern-recognition receptors (PRRs) is a key component of plant innate immunity. Most known plant PRRs are receptor kinases and initiation of PAMP-triggered immunity (PTI) signalling requires phosphorylation of the PR...

  1. Visual Speech Primes Open-Set Recognition of Spoken Words

    ERIC Educational Resources Information Center

    Buchwald, Adam B.; Winters, Stephen J.; Pisoni, David B.

    2009-01-01

    Visual speech perception has become a topic of considerable interest to speech researchers. Previous research has demonstrated that perceivers neurally encode and use speech information from the visual modality, and this information has been found to facilitate spoken word recognition in tasks such as lexical decision (Kim, Davis, & Krins, 2004).…

  2. Distributed Recognition of Natural Songs by European Starlings

    ERIC Educational Resources Information Center

    Knudsen, Daniel; Thompson, Jason V.; Gentner, Timothy Q.

    2010-01-01

    Individual vocal recognition behaviors in songbirds provide an excellent framework for the investigation of comparative psychological and neurobiological mechanisms that support the perception and cognition of complex acoustic communication signals. To this end, the complex songs of European starlings have been studied extensively. Yet, several…

  3. Multimodal eye recognition

    NASA Astrophysics Data System (ADS)

    Zhou, Zhi; Du, Yingzi; Thomas, N. L.; Delp, Edward J., III

    2010-04-01

    Multimodal biometrics use more than one means of biometric identification to achieve higher recognition accuracy, since sometimes a unimodal biometric is not good enough used to do identification and classification. In this paper, we proposed a multimodal eye recognition system, which can obtain both iris and sclera patterns from one color eye image. Gabor filter and 1-D Log-Gabor filter algorithms have been applied as the iris recognition algorithms. In sclera recognition, we introduced automatic sclera segmentation, sclera pattern enhancement, sclera pattern template generation, and sclera pattern matching. We applied kernelbased matching score fusion to improve the performance of the eye recognition system. The experimental results show that the proposed eye recognition method can achieve better performance compared to unimodal biometric identification, and the accuracy of our proposed kernel-based matching score fusion method is higher than two classic linear matching score fusion methods: Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA).

  4. Diagnostic odor recognition

    PubMed

    Rosenblatt; Phan; Desandre; Lobon; Hsu

    2000-10-01

    Many diseases, toxic ingestions, and intoxications have characteristic odors. These odors may provide diagnostic clues that affect rapid treatment long before laboratory confirmation or clinical deterioration. Odor recognition skills, similar to auscultation and palpation skills, require teaching and practical exposure. Dr. Goldfrank and colleagues recognized the importance of teaching odor recognition to emergency service providers. They proposed the "sniffing bar" method for odor recognition training. OBJECTIVES: (1) To identify the recognition rates of medically important odors among emergency care providers. (2) To investigate the effectiveness of teaching odor recognition. Hypothesis: The recognition rates of medically important odors will increase after teaching exposure. METHODS: The study exposed emergency care providers to 11 tubes of odors. Identifications of each substance were recorded. After corrective feedback, subjects were re-tested on their ability to identify the odors. Analysis of odor recognition improvement after teaching was done via chi-square test. RESULTS: Improvement in identification after teaching was seen in all odors. However, the improvement was significant only in the lesscommon substances because their initial recognition was especially low. Significant changes may improve with a larger sample size. Subjects often confuse the odors of alcohol with acetone, and wintergreen with camphor. CONCLUSIONS: The recognition rates are higher for the more-common odors, and lower for the less-common odors. Teaching exposures to the less well-known odors are effective and can significantly improve the recognition rate of these substances. Because odor recognition may affect rapid diagnosis and treatment of certain medical emergencies such as toxic ingestion, future studies should investigate the correlation between odor recognition and the ability to identify corresponding medical emergencies.

  5. Huntington's disease impairs recognition of angry and instrumental body language.

    PubMed

    de Gelder, Beatrice; Van den Stock, Jan; Balaguer, Ruth de Diego; Bachoud-Lévi, Anne-Catherine

    2008-01-15

    Patients with Huntington's disease (HD) exhibit motor impairments as well as cognitive and emotional deficits. So far impairments in the ability to recognize emotional stimuli have mostly been investigated by using facial expressions and emotional voices. Other important emotional signals are provided by the whole body. To investigate the impact of motor deficits on body recognition and the relation between motor disorders and emotion perception deficits, we tested recognition of emotional body language (instrumental, angry, fearful and sad) in 19 HD patients and their matched controls with a nonverbal whole body expression matching task. Results indicate that HD patients are impaired in recognizing both instrumental and angry whole body postures. Furthermore, the body language perception deficits are correlated with measures of motor deficit. Taken together the results suggest a close relationship between emotion recognition (specifically anger) and motor abilities. PMID:18061217

  6. Key considerations for the experimental training and evaluation of cancer odour detection dogs: lessons learnt from a double-blind, controlled trial of prostate cancer detection

    PubMed Central

    2014-01-01

    Background Cancer detection using sniffer dogs is a potential technology for clinical use and research. Our study sought to determine whether dogs could be trained to discriminate the odour of urine from men with prostate cancer from controls, using rigorous testing procedures and well-defined samples from a major research hospital. Methods We attempted to train ten dogs by initially rewarding them for finding and indicating individual prostate cancer urine samples (Stage 1). If dogs were successful in Stage 1, we then attempted to train them to discriminate prostate cancer samples from controls (Stage 2). The number of samples used to train each dog varied depending on their individual progress. Overall, 50 unique prostate cancer and 67 controls were collected and used during training. Dogs that passed Stage 2 were tested for their ability to discriminate 15 (Test 1) or 16 (Tests 2 and 3) unfamiliar prostate cancer samples from 45 (Test 1) or 48 (Tests 2 and 3) unfamiliar controls under double-blind conditions. Results Three dogs reached training Stage 2 and two of these learnt to discriminate potentially familiar prostate cancer samples from controls. However, during double-blind tests using new samples the two dogs did not indicate prostate cancer samples more frequently than expected by chance (Dog A sensitivity 0.13, specificity 0.71, Dog B sensitivity 0.25, specificity 0.75). The other dogs did not progress past Stage 1 as they did not have optimal temperaments for the sensitive odour discrimination training. Conclusions Although two dogs appeared to have learnt to select prostate cancer samples during training, they did not generalise on a prostate cancer odour during robust double-blind tests involving new samples. Our study illustrates that these rigorous tests are vital to avoid drawing misleading conclusions about the abilities of dogs to indicate certain odours. Dogs may memorise the individual odours of large numbers of training samples rather than

  7. [Disturbances in time perception in relation to changes in experiencing music in experimental psychosis].

    PubMed

    Weber, K

    1977-01-01

    Music is a structure ('Gestalt') in time. The recognition of disturbances of the perception of music enhances the knowledge of disorders of perception of time. Disturbances of perception of music and time in experimental psychoses (psilocybine) are discussed in relation to the studies by Piaget on the development of the notion of time in childhood. The results allow a new interpretation of the disturbances of the perception of time in diencephalic disorders as described in the literature. PMID:923240

  8. Lexical and context effects in children's audiovisual speech recognition

    NASA Astrophysics Data System (ADS)

    Holt, Rachael; Kirk, Karen; Pisoni, David; Burckhartzmeyer, Lisa; Lin, Anna

    2005-09-01

    The Audiovisual Lexical Neighborhood Sentence Test (AVLNST), a new, recorded speech recognition test for children with sensory aids, was administered in multiple presentation modalities to children with normal hearing and vision. Each sentence consists of three key words whose lexical difficulty is controlled according to the Neighborhood Activation Model (NAM) of spoken word recognition. According to NAM, the recognition of spoken words is influenced by two lexical factors: the frequency of occurrence of individual words in a language, and how phonemically similar the target word is to other words in the listeners lexicon. These predictions are based on auditory similarity only, and thus do not take into account how visual information can influence the perception of speech. Data from the AVLNST, together with those from recorded audiovisual versions of isolated word recognition measures, the Lexical Neighborhood, and the Multisyllabic Lexical Neighborhood Tests, were used to examine the influence of visual information on speech perception in children. Further, the influence of top-down processing on speech recognition was examined by evaluating performance on the recognition of words in isolation versus words in sentences. [Work supported by the American Speech-Language-Hearing Foundation, the American Hearing Research Foundation, and the NIDCD, T32 DC00012 to Indiana University.

  9. Moreland Recognition Program.

    ERIC Educational Resources Information Center

    Moreland Elementary School District, San Jose, CA.

    THE FOLLOWING IS THE FULL TEXT OF THIS DOCUMENT: Recognition for special effort and achievement has been noted as a component of effective schools. Schools in the Moreland School District have effectively improved standards of discipline and achievement by providing forty-six different ways for children to receive positive recognition. Good…

  10. Infant Visual Recognition Memory

    ERIC Educational Resources Information Center

    Rose, Susan A.; Feldman, Judith F.; Jankowski, Jeffery J.

    2004-01-01

    Visual recognition memory is a robust form of memory that is evident from early infancy, shows pronounced developmental change, and is influenced by many of the same factors that affect adult memory; it is surprisingly resistant to decay and interference. Infant visual recognition memory shows (a) modest reliability, (b) good discriminant…

  11. Music perception.

    PubMed

    Deutsch, Diana

    2007-05-01

    This chapter explores the relationship between music perception as it is studied in the laboratory and as it occurs in the real world. We first examine general principles by which listeners group musical tones into perceptual configurations, and how these principles are implemented in music composition and performance. We then show that, for certain types of configuration, the music as it is perceived can differ substantially from the music that is notated in the score, or as might be imagined from reading the score. Furthermore, there are striking differences between listeners in the perception of certain musical passages. Implications of these findings are discussed.

  12. Acquired prosopagnosia with spared within-class object recognition but impaired recognition of degraded basic-level objects.

    PubMed

    Rezlescu, Constantin; Pitcher, David; Duchaine, Brad

    2012-01-01

    We present a new case of acquired prosopagnosia resulting from extensive lesions predominantly in the right occipitotemporal cortex. Functional brain imaging revealed atypical activation of all core face areas in the right hemisphere, with reduced signal difference between faces and objects compared to controls. In contrast, Herschel's lateral occipital complex showed normal activation to objects. Behaviourally, Herschel is severely impaired with the recognition of familiar faces, discrimination between unfamiliar identities, and the perception of facial expression and gender. Notably, his visual recognition deficits are largely restricted to faces, suggesting that the damaged mechanisms are face-specific. He showed normal recognition memory for a wide variety of object classes in several paradigms, normal ability to discriminate between highly similar items within a novel object category, and intact ability to name basic objects (except four-legged animals). Furthermore, Herschel displayed a normal face composite effect and typical global advantage and global interference effects in the Navon task, suggesting spared integration of both face and nonface information. Nevertheless, he failed visual closure tests requiring recognition of basic objects from degraded images. This abnormality in basic object recognition is at odds with his spared within-class recognition and presents a challenge to hierarchical models of object perception.

  13. Too Fresh Is Unattractive! The Attraction of Newly Emerged Nicrophorus vespilloides Females to Odour Bouquets of Large Cadavers at Various Stages of Decomposition

    PubMed Central

    von Hoermann, Christian; Steiger, Sandra; Müller, Josef K.; Ayasse, Manfred

    2013-01-01

    The necrophagous burying beetle Nicrophorus vespilloides reproduces on small carcasses that are buried underground to serve as food for their offspring. Cadavers that are too large to bury have previously been postulated to be important food sources for newly emerged beetles; however, the attractiveness of distinct successive stages of decomposition were not further specified. Therefore, we investigated the potential preference of newly emerged N. vespilloides females for odour bouquets of piglet cadavers at specific stages of decomposition. Analyses of walking tracks on a Kramer sphere revealed a significantly higher mean walking speed and, consequently, a higher mean total track length when beetles were confronted with odour plumes of the decomposition stages ‘post-bloating’, ‘advanced decay’ or ‘dry remains’ in comparison with the solvent control. Such a change of the walking speed of newly emerged N. vespilloides females indicates a higher motivation to locate such food sources. In contrast to less discriminating individuals this behaviour provides the advantage of not wasting time at unsuitable food sources. Furthermore, in the advanced decay stage, we registered a significantly higher preference of beetles for upwind directions to its specific odour plume when compared with the solvent control. Such a change to upwind walking behaviour increases the likelihood that a large cadaver will be quickly located. Our findings are of general importance for applied forensic entomology: newly emerged N. vespilloides females on large cadavers can and should be regarded as potential indicators of prolonged post mortem intervals as our results clearly show that they prefer emitted odour bouquets of later decomposition stages. PMID:23516497

  14. Land application of sewage sludge: perceptions of New Jersey vegetable farmers.

    PubMed

    Krogmann, U; Gibson, V; Chess, C

    2001-04-01

    Understanding farmers' perceptions and choices regarding land application of sewage sludge is key to developing locally accepted strategies for managing its sewage sludge. Semi-structured interviews, with mostly open-ended questions were conducted with 50 fruit and vegetable farmers at the New Jersey Annual Vegetable Meeting in 1999. The in-depth interviews indicated that the application of sewage sludge to land is currently not a common agricultural practice for these growers. Perceived risks, including heavy metals in sewage sludge (soil-build up, crop-uptake), negative public perception, odour complaints, and increase of contaminants in the water supply outweigh economic incentives and soil improvement benefits. When naming benefits and drawbacks, farmers tend to think first of their crop and their land, and do not mention the environment. It is only when they are questioned directly about environmental benefits and risks that they discuss these aspects. Communication efforts should focus on practical information to which farmers can relate. PMID:11721995

  15. Smelling wrong: hormonal contraception in lemurs alters critical female odour cues.

    PubMed

    Crawford, Jeremy Chase; Boulet, Marylène; Drea, Christine M

    2011-01-01

    Animals, including humans, use olfaction to assess potential social and sexual partners. Although hormones modulate olfactory cues, we know little about whether contraception affects semiochemical signals and, ultimately, mate choice. We examined the effects of a common contraceptive, medroxyprogesterone acetate (MPA), on the olfactory cues of female ring-tailed lemurs (Lemur catta), and the behavioural response these cues generated in male conspecifics. The genital odorants of contracepted females were dramatically altered, falling well outside the range of normal female variation: MPA decreased the richness and modified the relative abundances of volatile chemicals expressed in labial secretions. Comparisons between treatment groups revealed several indicator compounds that could reliably signal female reproductive status to conspecifics. MPA also changed a female's individual chemical 'signature', while minimizing her chemical distinctiveness relative to other contracepted females. Most remarkably, MPA degraded the chemical patterns that encode honest information about genetic constitution, including individual diversity (heterozygosity) and pairwise relatedness to conspecifics. Lastly, males preferentially investigated the odorants of intact over contracepted females, clearly distinguishing those with immediate reproductive potential. By altering the olfactory cues that signal fertility, individuality, genetic quality and relatedness, contraceptives may disrupt intraspecific interactions in primates, including those relevant to kin recognition and mate choice. PMID:20667870

  16. Smelling wrong: hormonal contraception in lemurs alters critical female odour cues

    PubMed Central

    Crawford, Jeremy Chase; Boulet, Marylène; Drea, Christine M.

    2011-01-01

    Animals, including humans, use olfaction to assess potential social and sexual partners. Although hormones modulate olfactory cues, we know little about whether contraception affects semiochemical signals and, ultimately, mate choice. We examined the effects of a common contraceptive, medroxyprogesterone acetate (MPA), on the olfactory cues of female ring-tailed lemurs (Lemur catta), and the behavioural response these cues generated in male conspecifics. The genital odorants of contracepted females were dramatically altered, falling well outside the range of normal female variation: MPA decreased the richness and modified the relative abundances of volatile chemicals expressed in labial secretions. Comparisons between treatment groups revealed several indicator compounds that could reliably signal female reproductive status to conspecifics. MPA also changed a female's individual chemical ‘signature’, while minimizing her chemical distinctiveness relative to other contracepted females. Most remarkably, MPA degraded the chemical patterns that encode honest information about genetic constitution, including individual diversity (heterozygosity) and pairwise relatedness to conspecifics. Lastly, males preferentially investigated the odorants of intact over contracepted females, clearly distinguishing those with immediate reproductive potential. By altering the olfactory cues that signal fertility, individuality, genetic quality and relatedness, contraceptives may disrupt intraspecific interactions in primates, including those relevant to kin recognition and mate choice. PMID:20667870

  17. Acquisition of species-specific perfume blends: influence of habitat-dependent compound availability on odour choices of male orchid bees (Euglossa spp.).

    PubMed

    Pokorny, T; Hannibal, M; Quezada-Euan, J J G; Hedenström, E; Sjöberg, N; Bång, J; Eltz, T

    2013-06-01

    Male orchid bees (Euglossini, Apidae, Hymenoptera) expose species-specific blends of volatile chemicals (perfume bouquets) during their courtship display. The perfumes are acquired by collecting fragrant substances from environmental sources, which are then accumulated in specialised hind leg pouches. To balance the perfume composition, the males need to find and collect the required substances in specific relative amounts while facing seasonal, local or habitat-dependent differences in compound availability. Experience-dependent choice of odours, i.e. 'learned avoidance' of recently collected components, has been proposed as the mechanism that mediates the accumulation of the stereotypical compound ratios. In the present study, we used the presence of certain compounds in male hind leg pouches as proxy for the respective local compound availability, and investigated whether differences in content are correlated with differences in chemical choice assays. Our results suggest that volatile availability differs between localities (n = 16) as well as habitats (n = 2; coastal vs. inland) across the Yucatán peninsula, Mexico, for both studied species. Male Euglossa dilemma showed a pronounced preference for benzyl benzoate and eugenol at locations where those compounds were rare in hind leg extracts, as predicted by the learned avoidance model. No equivalent correlations were found for Euglossa viridissima. This is the first study to combine chemical analyses of perfumes with bioassays of odour choice. It strengthens the view that negative feedback from collected odours modifies future chemical choice and helps males to acquire specific perfume blends.

  18. Categorical perception.

    PubMed

    Goldstone, Robert L; Hendrickson, Andrew T

    2010-01-01

    Categorical perception (CP) is the phenomenon by which the categories possessed by an observer influences the observers' perception. Experimentally, CP is revealed when an observer's ability to make perceptual discriminations between things is better when those things belong to different categories rather than the same category, controlling for the physical difference between the things. We consider several core questions related to CP: Is it caused by innate and/or learned categories, how early in the information processing stream do categories influence perception, and what is the relation between ongoing linguistic processing and CP? CP for both speech and visual entities are surveyed, as are computational and mathematical models of CP. CP is an important phenomenon in cognitive science because it represents an essential adaptation of perception to support categorizations that an organism needs to make. Sensory signals that could be linearly related to physical qualities are warped in a nonlinear manner, transforming analog inputs into quasi-digital, quasi-symbolic encodings. Copyright © 2009 John Wiley & Sons, Ltd. For further resources related to this article, please visit the WIREs website. PMID:26272840

  19. Spatially resolved time-frequency analysis of odour coding in the insect antennal lobe.

    PubMed

    Paoli, Marco; Weisz, Nathan; Antolini, Renzo; Haase, Albrecht

    2016-09-01

    Antennal lobes constitute the first neurophils in the insect brain involved in coding and processing of olfactory information. With their stereotyped functional and anatomical organization, they provide an accessible model with which to investigate information processing of an external stimulus in a neural network in vivo. Here, by combining functional calcium imaging with time-frequency analysis, we have been able to monitor the oscillatory components of neural activity upon olfactory stimulation. The aim of this study is to investigate the presence of stimulus-induced oscillatory patterns in the honeybee antennal lobe, and to analyse the distribution of those patterns across the antennal lobe glomeruli. Fast two-photon calcium imaging reveals the presence of low-frequency oscillations, the intensity of which is perturbed by an incoming stimulus. Moreover, analysis of the spatial arrangement of this activity indicates that it is not homogeneous throughout the antennal lobe. On the contrary, each glomerulus displays an odorant-specific time-frequency profile, and acts as a functional unit of the oscillatory activity. The presented approach allows simultaneous recording of complex activity patterns across several nodes of the antennal lobe, providing the means to better understand the network dynamics regulating olfactory coding and leading to perception. PMID:27452956

  20. Subliminally Perceived Odours Modulate Female Intrasexual Competition: An Eye Movement Study

    PubMed Central

    Parma, Valentina; Tirindelli, Roberto; Bisazza, Angelo; Massaccesi, Stefano; Castiello, Umberto

    2012-01-01

    Background Evidence suggests that subliminal odorants influence human perception and behavior. It has been hypothesized that the human sex-steroid derived compound 4,16-androstadien-3-one (androstadienone) functions as a human chemosignal. The most intensively studied steroid compound, androstadienone is known to be biologically relevant since it seems to convey information about male mate quality to women. It is unclear if the effects of androstadienone are menstrual cycle related. Methodology/Principal Findings In the first experiment, heterosexual women were exposed to androstadienone or a control compound and asked to view stimuli such as female faces, male faces and familiar objects while their eye movements were recorded. In the second experiment the same women were asked to rate the level of stimuli attractiveness following exposure to the study or control compound. The results indicated that women at high conception risk spent more time viewing the female than the male faces regardless of the compound administered. Women at a low conception risk exhibited a preference for female faces only following exposure to androstadienone. Conclusions/Significance We contend that a woman's level of fertility influences her evaluation of potential competitors (e.g., faces of other women) during times critical for reproduction. Subliminally perceived odorants, such as androstadienone, might similarly enhance intrasexual competition strategies in women during fertility phases not critical for conception. These findings offer a substantial contribution to the current debate about the effects that subliminally perceived body odors might have on behavior. PMID:22383968

  1. Spatially resolved time-frequency analysis of odour coding in the insect antennal lobe.

    PubMed

    Paoli, Marco; Weisz, Nathan; Antolini, Renzo; Haase, Albrecht

    2016-09-01

    Antennal lobes constitute the first neurophils in the insect brain involved in coding and processing of olfactory information. With their stereotyped functional and anatomical organization, they provide an accessible model with which to investigate information processing of an external stimulus in a neural network in vivo. Here, by combining functional calcium imaging with time-frequency analysis, we have been able to monitor the oscillatory components of neural activity upon olfactory stimulation. The aim of this study is to investigate the presence of stimulus-induced oscillatory patterns in the honeybee antennal lobe, and to analyse the distribution of those patterns across the antennal lobe glomeruli. Fast two-photon calcium imaging reveals the presence of low-frequency oscillations, the intensity of which is perturbed by an incoming stimulus. Moreover, analysis of the spatial arrangement of this activity indicates that it is not homogeneous throughout the antennal lobe. On the contrary, each glomerulus displays an odorant-specific time-frequency profile, and acts as a functional unit of the oscillatory activity. The presented approach allows simultaneous recording of complex activity patterns across several nodes of the antennal lobe, providing the means to better understand the network dynamics regulating olfactory coding and leading to perception.

  2. The neural correlates of visual self-recognition.

    PubMed

    Devue, Christel; Brédart, Serge

    2011-03-01

    This paper presents a review of studies that were aimed at determining which brain regions are recruited during visual self-recognition, with a particular focus on self-face recognition. A complex bilateral network, involving frontal, parietal and occipital areas, appears to be associated with self-face recognition, with a particularly high implication of the right hemisphere. Results indicate that it remains difficult to determine which specific cognitive operation is reflected by each recruited brain area, in part due to the variability of used control stimuli and experimental tasks. A synthesis of the interpretations provided by previous studies is presented. The relevance of using self-recognition as an indicator of self-awareness is discussed. We argue that a major aim of future research in the field should be to identify more clearly the cognitive operations induced by the perception of the self-face, and search for dissociations between neural correlates and cognitive components.

  3. Assessing collective affect recognition via the Emotional Aperture Measure.

    PubMed

    Sanchez-Burks, Jeffrey; Bartel, Caroline A; Rees, Laura; Huy, Quy

    2016-01-01

    Curiosity about collective affect is undergoing a revival in many fields. This literature, tracing back to Le Bon's seminal work on crowd psychology, has established the veracity of collective affect and demonstrated its influence on a wide range of group dynamics. More recently, an interest in the perception of collective affect has emerged, revealing a need for a methodological approach for assessing collective emotion recognition to complement measures of individual emotion recognition. This article addresses this need by introducing the Emotional Aperture Measure (EAM). Three studies provide evidence that collective affect recognition requires a processing style distinct from individual emotion recognition and establishes the validity and reliability of the EAM. A sample of working managers further shows how the EAM provides unique insights into how individuals interact with collectives. We discuss how the EAM can advance several lines of research on collective affect. PMID:25809581

  4. Developmental Commonalities between Object and Face Recognition in Adolescence

    PubMed Central

    Jüttner, Martin; Wakui, Elley; Petters, Dean; Davidoff, Jules

    2016-01-01

    In the visual perception literature, the recognition of faces has often been contrasted with that of non-face objects, in terms of differences with regard to the role of parts, part relations and holistic processing. However, recent evidence from developmental studies has begun to blur this sharp distinction. We review evidence for a protracted development of object recognition that is reminiscent of the well-documented slow maturation observed for faces. The prolonged development manifests itself in a retarded processing of metric part relations as opposed to that of individual parts and offers surprising parallels to developmental accounts of face recognition, even though the interpretation of the data is less clear with regard to holistic processing. We conclude that such results might indicate functional commonalities between the mechanisms underlying the recognition of faces and non-face objects, which are modulated by different task requirements in the two stimulus domains. PMID:27014176

  5. Assessing collective affect recognition via the Emotional Aperture Measure.

    PubMed

    Sanchez-Burks, Jeffrey; Bartel, Caroline A; Rees, Laura; Huy, Quy

    2016-01-01

    Curiosity about collective affect is undergoing a revival in many fields. This literature, tracing back to Le Bon's seminal work on crowd psychology, has established the veracity of collective affect and demonstrated its influence on a wide range of group dynamics. More recently, an interest in the perception of collective affect has emerged, revealing a need for a methodological approach for assessing collective emotion recognition to complement measures of individual emotion recognition. This article addresses this need by introducing the Emotional Aperture Measure (EAM). Three studies provide evidence that collective affect recognition requires a processing style distinct from individual emotion recognition and establishes the validity and reliability of the EAM. A sample of working managers further shows how the EAM provides unique insights into how individuals interact with collectives. We discuss how the EAM can advance several lines of research on collective affect.

  6. PCA facial expression recognition

    NASA Astrophysics Data System (ADS)

    El-Hori, Inas H.; El-Momen, Zahraa K.; Ganoun, Ali

    2013-12-01

    This paper explores and compares techniques for automatically recognizing facial actions in sequences of images. The comparative study of Facial Expression Recognition (FER) techniques namely Principal Component's analysis (PCA) and PCA with Gabor filters (GF) is done. The objective of this research is to show that PCA with Gabor filters is superior to the first technique in terms of recognition rate. To test and evaluates their performance, experiments are performed using real database by both techniques. The universally accepted five principal emotions to be recognized are: Happy, Sad, Disgust and Angry along with Neutral. The recognition rates are obtained on all the facial expressions.

  7. Emotional Perception Deficits in Amyotrophic Lateral Sclerosis

    PubMed Central

    Zimmerman BA, Erin K.; Eslinger PhD, Paul J.; MD, Zachary Simmons; Barrett MD, Anna M.

    2007-01-01

    Objective Cognitive deficits associated with frontal lobe dysfunction can occur in amyotrophic lateral sclerosis (ALS), particularly in individuals with bulbar ALS who can also suffer pathological emotional lability. Since frontal pathophysiology can alter emotional perception, we examined whether emotional perception deficits occur in ALS, and whether they are related to depressive or dementia symptoms. Methods Bulbar ALS participants (n = 13) and age-matched healthy normal controls (n = 12) completed standardized tests of facial and prosodic emotional recognition, the Geriatric Depression Scale, and the Mini-Mental State Examination. Participants identified the basic emotion (happy, sad, angry, afraid, surprised, disgusted) that matched 39 facial expressions and 28 taped, semantically neutral, intoned sentences. Results ALS patients performed significantly worse than controls on facial emotional recognition but not on prosodic emotional recognition. Eight of 13 patients (62%) scored below the 95% Confidence Interval of controls in recognizing facial emotions, and 3 of these patients (23% overall) also scored lower in prosody recognition. Among the 8 patients with emotional perceptual impairment, one-half did not have depressive, or memory or cognitive symptoms on screening, while the remainder showed dementia symptoms alone or together with depressive symptoms. Conclusions Emotional recognition deficits occur in bulbar ALS, particularly with emotional facial expressions, and can arise independent of depressive and dementia symptoms or co-morbid with depression and dementia. These findings expands the scope of cognitive dysfunction detected in ALS, and bolsters the view of ALS as a multisystem disorder involving cognitive as well as motor deficits. PMID:17558250

  8. Chemical compositions and muddy flavour/odour of protein hydrolysate from Nile tilapia and broadhead catfish mince and protein isolate.

    PubMed

    Yarnpakdee, Suthasinee; Benjakul, Soottawat; Penjamras, Pimpimol; Kristinsson, Hordur G

    2014-01-01

    Chemical compositions and muddy compounds in dorsal and ventral muscles of Nile tilapia and broadhead catfish were comparatively studied. On a dry weight basis, Nile tilapia was rich in protein (93.1-93.8%), whilst broadhead catfish contained protein (55.2-59.5%) and lipid (36.6-42.4%) as the major constituents. Ventral portion had higher lipid or phospholipid contents with coincidentally higher geosmin and/or 2-methylisoborneol (2-MIB) contents. Geosmin was found in mince of Nile tilapia and broadhead catfish at levels of 1.5 and 3.2μg/kg, respectively. Broadhead catfish mince had 2-MIB at level of 0.8μg/kg, but no 2-MIB was detected in Nile tilapia counterpart. When pre-washing and alkaline solubilisation were applied for preparing protein isolate (PI), lipid and phospholipid contents were lowered with concomitant decrease in geosmin and 2-MIB contents. Protein hydrolysate produced from PI had a lighter colour and a lower amount of muddy compounds, compared with that prepared from mince. Therefore, PI from both Nile tilapia and broadhead catfish could serve as the promising proteinaceous material, yielding protein hydrolysate with the negligible muddy odour and flavour. PMID:24001833

  9. Characterisation of aroma profiles of commercial sufus by odour activity value, gas chromatography-olfactometry, aroma recombination and omission studies.

    PubMed

    Xiao, Zuobing; Shang, Yi; Chen, Feng; Niu, Yunwei; Gu, Yongbo; Liu, Shengjiang; Zhu, Jiancai

    2015-01-01

    Sufu is a solid-state fermented product made from soya beans. For the sake of quality control and regulation purposes, it is essential to be able to identify key odorants of various commercial sufus. To identify the aroma-active compounds in sufus, gas chromatography-olfactometry/aroma extract dilution analysis (GC-O/AEDA) was performed, and odour activity value (OAV) was estimated. The correlations between aroma profiles and identified aroma-active compounds were also investigated by principal component analysis. Results showed that 35 aroma-active compounds were detected through OAV calculation, while 28 compounds were identified by using GC-O/AEDA. Quantitative descriptive analysis revealed that aroma recombination model based on OAV calculation was more similar to original sufu in terms of aroma comparing to aroma recombination model based on GC-O/AEDA. Omission experiments further confirmed that the aroma compounds, such as ethyl butanoate, ethyl 2-methylbutanoate, ethyl hexanoate, (E,E)-2,4-decadienal and 2,6-dimethylpyrazine, contributed most significantly to the characteristic aroma of a commercial sufu.

  10. A sensitivity analysis of process design parameters, commodity prices and robustness on the economics of odour abatement technologies.

    PubMed

    Estrada, José M; Kraakman, N J R Bart; Lebrero, Raquel; Muñoz, Raúl

    2012-01-01

    The sensitivity of the economics of the five most commonly applied odour abatement technologies (biofiltration, biotrickling filtration, activated carbon adsorption, chemical scrubbing and a hybrid technology consisting of a biotrickling filter coupled with carbon adsorption) towards design parameters and commodity prices was evaluated. Besides, the influence of the geographical location on the Net Present Value calculated for a 20 years lifespan (NPV20) of each technology and its robustness towards typical process fluctuations and operational upsets were also assessed. This comparative analysis showed that biological techniques present lower operating costs (up to 6 times) and lower sensitivity than their physical/chemical counterparts, with the packing material being the key parameter affecting their operating costs (40-50% of the total operating costs). The use of recycled or partially treated water (e.g. secondary effluent in wastewater treatment plants) offers an opportunity to significantly reduce costs in biological techniques. Physical/chemical technologies present a high sensitivity towards H2S concentration, which is an important drawback due to the fluctuating nature of malodorous emissions. The geographical analysis evidenced high NPV20 variations around the world for all the technologies evaluated, but despite the differences in wage and price levels, biofiltration and biotrickling filtration are always the most cost-efficient alternatives (NPV20). When, in an economical evaluation, the robustness is as relevant as the overall costs (NPV20), the hybrid technology would move up next to BTF as the most preferred technologies.

  11. Identification of potent odourants in wine and brewed coffee using gas chromatography-olfactometry and comprehensive two-dimensional gas chromatography.

    PubMed

    Chin, Sung-Tong; Eyres, Graham T; Marriott, Philip J

    2011-10-21

    Volatile constituents in wine and brewed coffee were analyzed using a combined system incorporating both GC-olfactometry (GC-O) and comprehensive two-dimensional GC-flame ionization detection (GC×GC-FID). A column set consisting of a 15m first dimension ((1)D; DB-FFAP (free fatty acid phase)), and a 1.0m (2)D column (DB-5 phase) was applied to achieve the GC×GC separation of the volatile extracts isolated by using solid phase extraction (SPE). While 1D GC resulted in many overlapping peaks, GC×GC allowed resolution of co-eluting compounds which coincided with the odour region located using GC-O. Character-impact odourants were tentatively identified through data correlation of GC×GC contour plots across results obtained using either time-of-flight mass spectrometry (TOFMS), or with flame photometric detection (FPD) for sulfur speciation. The odourants 2-methyl-2-butenal, 2-(methoxymethyl)-furan, dimethyl trisulfide, 2-ethyl-5-methyl-pyrazine, 2-octenal, 2-furancarboxaldehyde, 3-mercapto-3-methyl-1-butanol, 2-methoxy-3-(2-methylpropyl)-pyrazine, 2-furanmethanol and isovaleric acid were suspected to be particularly responsible for coffee aroma using this approach. The presented methodology was applied to identify the potent odourants in two different Australian wine varietals. 1-Octen-3-ol, butanoic acid and 2-methylbutanoic acid were detected in both Merlot and a Sauvignon Blanc+Semillon (SV) blend with high aroma potency. Several co-eluting peaks of ethyl 4-oxo-pentanoate, 3,7-dimethyl-1,5,7-octatrien-3-ol, (Z)-2-octen-1-ol, 5-hydroxy-2-methyl-1,3-dioxane were likely contributors to the Merlot wine aroma; while (Z)-3-hexen-1-ol, β-phenylethyl acetate, hexanoic acid and co-eluting peaks of 3-ethoxy-1-propanol and hexyl formate may contribute to SV wine aroma character. The volatile sulfur compound 2-mercapto-ethyl acetate was believed to contribute a fruity, brothy, meaty, sulfur odour to Australian Merlot and SV wines. PMID:21741655

  12. Pattern recognition technique

    NASA Technical Reports Server (NTRS)

    Hong, J. P.

    1971-01-01

    Technique operates regardless of pattern rotation, translation or magnification and successfully detects out-of-register patterns. It improves accuracy and reduces cost of various optical character recognition devices and page readers and provides data input to computer.

  13. Context based gait recognition

    NASA Astrophysics Data System (ADS)

    Bazazian, Shermin; Gavrilova, Marina

    2012-06-01

    Gait recognition has recently become a popular topic in the field of biometrics. However, the main hurdle is the insufficient recognition rate in the presence of low quality samples. The main focus of this paper is to investigate how the performance of a gait recognition system can be improved using additional information about behavioral patterns of users and the context in which samples have been taken. The obtained results show combining the context information with biometric data improves the performance of the system at a very low cost. The amount of improvement depends on the distinctiveness of the behavioral patterns and the quality of the gait samples. Using the appropriate distinctive behavioral models it is possible to achieve a 100% recognition rate.

  14. CASE Recognition Awards.

    ERIC Educational Resources Information Center

    Currents, 1985

    1985-01-01

    A total of 294 schools, colleges, and universities received prizes in this year's CASE Recognition program. Awards were given in: public relations programs, student recruitment, marketing, program pulications, news writing, fund raising, radio programming, school periodicals, etc. (MLW)

  15. Progress in fold recognition.

    PubMed

    Flöckner, H; Braxenthaler, M; Lackner, P; Jaritz, M; Ortner, M; Sippl, M J

    1995-11-01

    The prediction experiment reveals that fold recognition has become a powerful tool in structural biology. We applied our fold recognition technique to 13 target sequences. In two cases, replication terminating protein and prosequence of subtilisin, the predicted structures are very similar to the experimentally determined folds. For the first time, in a public blind test, the unknown structures of proteins have been predicted ahead of experiment to an accuracy approaching molecular detail. In two other cases the approximate folds have been predicted correctly. According to the assessors there were 12 recognizable folds among the target proteins. In our postprediction analysis we find that in 7 cases our fold recognition technique is successful. In several of the remaining cases the predicted folds have interesting features in common with the experimental results. We present our procedure, discuss the results, and comment on several fundamental and technical problems encountered in fold recognition.

  16. Temporal lobe structures and facial emotion recognition in schizophrenia patients and nonpsychotic relatives.

    PubMed

    Goghari, Vina M; Macdonald, Angus W; Sponheim, Scott R

    2011-11-01

    Temporal lobe abnormalities and emotion recognition deficits are prominent features of schizophrenia and appear related to the diathesis of the disorder. This study investigated whether temporal lobe structural abnormalities were associated with facial emotion recognition deficits in schizophrenia and related to genetic liability for the disorder. Twenty-seven schizophrenia patients, 23 biological family members, and 36 controls participated. Several temporal lobe regions (fusiform, superior temporal, middle temporal, amygdala, and hippocampus) previously associated with face recognition in normative samples and found to be abnormal in schizophrenia were evaluated using volumetric analyses. Participants completed a facial emotion recognition task and an age recognition control task under time-limited and self-paced conditions. Temporal lobe volumes were tested for associations with task performance. Group status explained 23% of the variance in temporal lobe volume. Left fusiform gray matter volume was decreased by 11% in patients and 7% in relatives compared with controls. Schizophrenia patients additionally exhibited smaller hippocampal and middle temporal volumes. Patients were unable to improve facial emotion recognition performance with unlimited time to make a judgment but were able to improve age recognition performance. Patients additionally showed a relationship between reduced temporal lobe gray matter and poor facial emotion recognition. For the middle temporal lobe region, the relationship between greater volume and better task performance was specific to facial emotion recognition and not age recognition. Because schizophrenia patients exhibited a specific deficit in emotion recognition not attributable to a generalized impairment in face perception, impaired emotion recognition may serve as a target for interventions.

  17. [Electrocardiograph beat pattern recognition].

    PubMed

    Zhou, Qunyi; Lu, Xudong; Duan, Huiling

    2005-02-01

    It is very important to recognize arrhythmia in clinical electrocardiography (ECG) analysis. The fundamental of beat pattern recognition is presented in this paper. Various prevalent methods for arrhythmia recognitiion are categorized and summarized, based on which the advantages and disadvantages among the methods are compared, and the main problems are discussed in depth. At last, the development trend of arrhythmia recognition technology is pointed out.

  18. Implementation of perceptual aspects in a face recognition algorithm

    NASA Astrophysics Data System (ADS)

    Crenna, F.; Zappa, E.; Bovio, L.; Testa, R.; Gasparetto, M.; Rossi, G. B.

    2013-09-01

    Automatic face recognition is a biometric technique particularly appreciated in security applications. In fact face recognition presents the opportunity to operate at a low invasive level without the collaboration of the subjects under tests, with face images gathered either from surveillance systems or from specific cameras located in strategic points. The automatic recognition algorithms perform a measurement, on the face images, of a set of specific characteristics of the subject and provide a recognition decision based on the measurement results. Unfortunately several quantities may influence the measurement of the face geometry such as its orientation, the lighting conditions, the expression and so on, affecting the recognition rate. On the other hand human recognition of face is a very robust process far less influenced by the surrounding conditions. For this reason it may be interesting to insert perceptual aspects in an automatic facial-based recognition algorithm to improve its robustness. This paper presents a first study in this direction investigating the correlation between the results of a perception experiment and the facial geometry, estimated by means of the position of a set of repere points.

  19. Eye movements during object recognition in visual agnosia.

    PubMed

    Charles Leek, E; Patterson, Candy; Paul, Matthew A; Rafal, Robert; Cristino, Filipe

    2012-07-01

    This paper reports the first ever detailed study about eye movement patterns during single object recognition in visual agnosia. Eye movements were recorded in a patient with an integrative agnosic deficit during two recognition tasks: common object naming and novel object recognition memory. The patient showed normal directional biases in saccades and fixation dwell times in both tasks and was as likely as controls to fixate within object bounding contour regardless of recognition accuracy. In contrast, following initial saccades of similar amplitude to controls, the patient showed a bias for short saccades. In object naming, but not in recognition memory, the similarity of the spatial distributions of patient and control fixations was modulated by recognition accuracy. The study provides new evidence about how eye movements can be used to elucidate the functional impairments underlying object recognition deficits. We argue that the results reflect a breakdown in normal functional processes involved in the integration of shape information across object structure during the visual perception of shape.

  20. Neural Mechanisms and Information Processing in Recognition Systems

    PubMed Central

    Ozaki, Mamiko; Hefetz, Abraham

    2014-01-01

    Nestmate recognition is a hallmark of social insects. It is based on the match/mismatch of an identity signal carried by members of the society with that of the perceiving individual. While the behavioral response, amicable or aggressive, is very clear, the neural systems underlying recognition are not fully understood. Here we contrast two alternative hypotheses for the neural mechanisms that are responsible for the perception and information processing in recognition. We focus on recognition via chemical signals, as the common modality in social insects. The first, classical, hypothesis states that upon perception of recognition cues by the sensory system the information is passed as is to the antennal lobes and to higher brain centers where the information is deciphered and compared to a neural template. Match or mismatch information is then transferred to some behavior-generating centers where the appropriate response is elicited. An alternative hypothesis, that of “pre-filter mechanism”, posits that the decision as to whether to pass on the information to the central nervous system takes place in the peripheral sensory system. We suggest that, through sensory adaptation, only alien signals are passed on to the brain, specifically to an “aggressive-behavior-switching center”, where the response is generated if the signal is above a certain threshold. PMID:26462936

  1. Visual body recognition in a prosopagnosic patient.

    PubMed

    Moro, V; Pernigo, S; Avesani, R; Bulgarelli, C; Urgesi, C; Candidi, M; Aglioti, S M

    2012-01-01

    Conspicuous deficits in face recognition characterize prosopagnosia. Information on whether agnosic deficits may extend to non-facial body parts is lacking. Here we report the neuropsychological description of FM, a patient affected by a complete deficit in face recognition in the presence of mild clinical signs of visual object agnosia. His deficit involves both overt and covert recognition of faces (i.e. recognition of familiar faces, but also categorization of faces for gender or age) as well as the visual mental imagery of faces. By means of a series of matching-to-sample tasks we investigated: (i) a possible association between prosopagnosia and disorders in visual body perception; (ii) the effect of the emotional content of stimuli on the visual discrimination of faces, bodies and objects; (iii) the existence of a dissociation between identity recognition and the emotional discrimination of faces and bodies. Our results document, for the first time, the co-occurrence of body agnosia, i.e. the visual inability to discriminate body forms and body actions, and prosopagnosia. Moreover, the results show better performance in the discrimination of emotional face and body expressions with respect to body identity and neutral actions. Since FM's lesions involve bilateral fusiform areas, it is unlikely that the amygdala-temporal projections explain the relative sparing of emotion discrimination performance. Indeed, the emotional content of the stimuli did not improve the discrimination of their identity. The results hint at the existence of two segregated brain networks involved in identity and emotional discrimination that are at least partially shared by face and body processing.

  2. Page Recognition: Quantum Leap In Recognition Technology

    NASA Astrophysics Data System (ADS)

    Miller, Larry

    1989-07-01

    No milestone has proven as elusive as the always-approaching "year of the LAN," but the "year of the scanner" might claim the silver medal. Desktop scanners have been around almost as long as personal computers. And everyone thinks they are used for obvious desktop-publishing and business tasks like scanning business documents, magazine articles and other pages, and translating those words into files your computer understands. But, until now, the reality fell far short of the promise. Because it's true that scanners deliver an accurate image of the page to your computer, but the software to recognize this text has been woefully disappointing. Old optical-character recognition (OCR) software recognized such a limited range of pages as to be virtually useless to real users. (For example, one OCR vendor specified 12-point Courier font from an IBM Selectric typewriter: the same font in 10-point, or from a Diablo printer, was unrecognizable!) Computer dealers have told me the chasm between OCR expectations and reality is so broad and deep that nine out of ten prospects leave their stores in disgust when they learn the limitations. And this is a very important, very unfortunate gap. Because the promise of recognition -- what people want it to do -- carries with it tremendous improvements in our productivity and ability to get tons of written documents into our computers where we can do real work with it. The good news is that a revolutionary new development effort has led to the new technology of "page recognition," which actually does deliver the promise we've always wanted from OCR. I'm sure every reader appreciates the breakthrough represented by the laser printer and page-makeup software, a combination so powerful it created new reasons for buying a computer. A similar breakthrough is happening right now in page recognition: the Macintosh (and, I must admit, other personal computers) equipped with a moderately priced scanner and OmniPage software (from Caere

  3. Developmental prosopagnosia and super-recognition: no special role for surface reflectance processing

    PubMed Central

    Russell, Richard; Chatterjee, Garga; Nakayama, Ken

    2011-01-01

    Face recognition by normal subjects depends in roughly equal proportions on shape and surface reflectance cues, while object recognition depends predominantly on shape cues. It is possible that developmental prosopagnosics are deficient not in their ability to recognize faces per se, but rather in their ability to use reflectance cues. Similarly, super-recognizers’ exceptional ability with face recognition may be a result of superior surface reflectance perception and memory. We tested this possibility by administering tests of face perception and face recognition in which only shape or reflectance cues are available to developmental prosopagnosics, super-recognizers, and control subjects. Face recognition ability and the relative use of shape and pigmentation were unrelated in all the tests. Subjects who were better at using shape or reflectance cues were also better at using the other type of cue. These results do not support the proposal that variation in surface reflectance perception ability is the underlying cause of variation in face recognition ability. Instead, these findings support the idea that face recognition ability is related to neural circuits using representations that integrate shape and pigmentation information. PMID:22192636

  4. Emotion recognition (sometimes) depends on horizontal orientations

    PubMed Central

    Huynh, Carol M; Balas, Benjamin

    2014-01-01

    Face recognition depends critically on horizontal orientations (Goffaux & Dakin, 2010). Face images that lack horizontal features are harder to recognize than those that have that information preserved. Presently, we asked if facial emotional recognition also exhibits this dependency by asking observers to categorize orientation-filtered happy and sad expressions. Furthermore, we aimed to dissociate image-based orientation energy from object-based orientation by rotating images 90-degrees in the picture-plane. In our first experiment, we showed that the perception of emotional expression does depend on horizontal orientations and that object-based orientation constrained performance more than image-based orientation. In Experiment 2 we showed that mouth openness (i.e. open versus closed-mouths) also influenced the emotion-dependent reliance on horizontal information. Lastly, we describe a simple computational analysis that demonstrates that the impact of mouth openness was not predicted by variation in the distribution of orientation energy across horizontal and vertical orientation bands. Overall, our results suggest that emotion recognition does largely depend on horizontal information defined relative to the face, but that this bias is modulated by multiple factors that introduce variation in appearance across and within distinct emotions. PMID:24664854

  5. Analysis of odour compounds from scented consumer products using gas chromatography-mass spectrometry and gas chromatography-olfactometry.

    PubMed

    Bartsch, Jennifer; Uhde, Erik; Salthammer, Tunga

    2016-01-21

    Scented consumer products are being bought in increasing amounts and gaining more popularity. There is, however, relatively little information available about their ingredients, emissions and allergenic potential. Frequently, a mixture of different fragrance substances and not solely an individual substance contributes to the overall desired smell. The aim of this study was to investigate the odorous volatile organic compounds (OVOCs) in consumer products containing fragrances. Over 44 products were selected: various scented candles, printing products with different scent types and other products types particularly meant to be used indoors. Measurements were carried out in a desiccator. Air samples were collected on thermal desorption tubes to determine the released fragrance substances by means of gas chromatography-mass spectrometry (GC-MS). Moreover, gas chromatography-olfactometry (GC-O) was used to obtain sensory data and to ensure no important odorant was overlooked. Using both methods it was possible to distinguish between odour active and inactive compounds and subsequently to identify almost 300 different odorants across all scented products. Besides the advantage of differentiation, as the human nose is a very sensitive detector, GC-O was found to be a useful tool for detecting traces and chosen target compounds. One focus in this study lay on the 26 EU-regulated fragrance allergens to prove their relevance in scented consumer goods. In total, 18 of them were identified, with at least one substance being present in almost every product. Benzyl alcohol, cinnamaldehyde, citronellol, eugenol, linalool and limonene were the prevalently detected allergens. Particularly linalool and limonene were observed in over 50% of the products. In addition, eugenol appeared to be one of the most frequently detected compounds in trace-level concentrations in the candle emissions.

  6. Analysis of odour compounds from scented consumer products using gas chromatography-mass spectrometry and gas chromatography-olfactometry.

    PubMed

    Bartsch, Jennifer; Uhde, Erik; Salthammer, Tunga

    2016-01-21

    Scented consumer products are being bought in increasing amounts and gaining more popularity. There is, however, relatively little information available about their ingredients, emissions and allergenic potential. Frequently, a mixture of different fragrance substances and not solely an individual substance contributes to the overall desired smell. The aim of this study was to investigate the odorous volatile organic compounds (OVOCs) in consumer products containing fragrances. Over 44 products were selected: various scented candles, printing products with different scent types and other products types particularly meant to be used indoors. Measurements were carried out in a desiccator. Air samples were collected on thermal desorption tubes to determine the released fragrance substances by means of gas chromatography-mass spectrometry (GC-MS). Moreover, gas chromatography-olfactometry (GC-O) was used to obtain sensory data and to ensure no important odorant was overlooked. Using both methods it was possible to distinguish between odour active and inactive compounds and subsequently to identify almost 300 different odorants across all scented products. Besides the advantage of differentiation, as the human nose is a very sensitive detector, GC-O was found to be a useful tool for detecting traces and chosen target compounds. One focus in this study lay on the 26 EU-regulated fragrance allergens to prove their relevance in scented consumer goods. In total, 18 of them were identified, with at least one substance being present in almost every product. Benzyl alcohol, cinnamaldehyde, citronellol, eugenol, linalool and limonene were the prevalently detected allergens. Particularly linalool and limonene were observed in over 50% of the products. In addition, eugenol appeared to be one of the most frequently detected compounds in trace-level concentrations in the candle emissions. PMID:26724768

  7. Pitch perception.

    PubMed

    Oxenham, Andrew J

    2012-09-26

    Pitch is one of the primary auditory sensations and plays a defining role in music, speech, and auditory scene analysis. Although the main physical correlate of pitch is acoustic periodicity, or repetition rate, there are many interactions that complicate the relationship between the physical stimulus and the perception of pitch. In particular, the effects of other acoustic parameters on pitch judgments, and the complex interactions between perceptual organization and pitch, have uncovered interesting perceptual phenomena that should help to reveal the underlying neural mechanisms. PMID:23015422

  8. Probabilistic Open Set Recognition

    NASA Astrophysics Data System (ADS)

    Jain, Lalit Prithviraj

    Real-world tasks in computer vision, pattern recognition and machine learning often touch upon the open set recognition problem: multi-class recognition with incomplete knowledge of the world and many unknown inputs. An obvious way to approach such problems is to develop a recognition system that thresholds probabilities to reject unknown classes. Traditional rejection techniques are not about the unknown; they are about the uncertain boundary and rejection around that boundary. Thus traditional techniques only represent the "known unknowns". However, a proper open set recognition algorithm is needed to reduce the risk from the "unknown unknowns". This dissertation examines this concept and finds existing probabilistic multi-class recognition approaches are ineffective for true open set recognition. We hypothesize the cause is due to weak adhoc assumptions combined with closed-world assumptions made by existing calibration techniques. Intuitively, if we could accurately model just the positive data for any known class without overfitting, we could reject the large set of unknown classes even under this assumption of incomplete class knowledge. For this, we formulate the problem as one of modeling positive training data by invoking statistical extreme value theory (EVT) near the decision boundary of positive data with respect to negative data. We provide a new algorithm called the PI-SVM for estimating the unnormalized posterior probability of class inclusion. This dissertation also introduces a new open set recognition model called Compact Abating Probability (CAP), where the probability of class membership decreases in value (abates) as points move from known data toward open space. We show that CAP models improve open set recognition for multiple algorithms. Leveraging the CAP formulation, we go on to describe the novel Weibull-calibrated SVM (W-SVM) algorithm, which combines the useful properties of statistical EVT for score calibration with one-class and binary

  9. Toward hyperspectral face recognition

    NASA Astrophysics Data System (ADS)

    Robila, Stefan A.

    2008-02-01

    Face recognition continues to meet significant challenges in reaching accurate results and still remains one of the activities where humans outperform technology. An attractive approach in improving face identification is provided by the fusion of multiple imaging sources such as visible and infrared images. Hyperspectral data, i.e. images collected over hundreds of narrow contiguous light spectrum intervals constitute a natural choice for expanding face recognition image fusion, especially since it may provide information beyond the normal visible range, thus exceeding the normal human sensing. In this paper we investigate the efficiency of hyperspectral face recognition through an in house experiment that collected data in over 120 bands within the visible and near infrared range. The imagery was produced using an off the shelf sensor in both indoors and outdoors with the subjects being photographed from various angles. Further processing included spectra collection and feature extraction. Human matching performance based on spectral properties is discussed.

  10. Temporal Integration in Face Perception: Evidence of Configural Processing of Temporally Separated Face Parts

    ERIC Educational Resources Information Center

    Anaki, David; Boyd, Jennifer; Moscovitch, Morris

    2007-01-01

    Temporal integration is the process by which temporally separated visual components are combined into a unified representation. Although this process has been studied in object recognition, little is known about temporal integration in face perception and recognition. In the present study, the authors investigated the characteristics and time…

  11. Improving Negative Emotion Recognition in Young Offenders Reduces Subsequent Crime

    PubMed Central

    Hubble, Kelly; Bowen, Katharine L.; Moore, Simon C.; van Goozen, Stephanie H. M.

    2015-01-01

    Background Children with antisocial behaviour show deficits in the perception of emotional expressions in others that may contribute to the development and persistence of antisocial and aggressive behaviour. Current treatments for antisocial youngsters are limited in effectiveness. It has been argued that more attention should be devoted to interventions that target neuropsychological correlates of antisocial behaviour. This study examined the effect of emotion recognition training on criminal behaviour. Methods Emotion recognition and crime levels were studied in 50 juvenile offenders. Whilst all young offenders received their statutory interventions as the study was conducted, a subgroup of twenty-four offenders also took part in a facial affect training aimed at improving emotion recognition. Offenders in the training and control groups were matched for age, SES, IQ and lifetime crime level. All offenders were tested twice for emotion recognition performance, and recent crime data were collected after the testing had been completed. Results Before the training there were no differences between the groups in emotion recognition, with both groups displaying poor fear, sadness and anger recognition. After the training fear, sadness and anger recognition improved significantly in juvenile offenders in the training group. Although crime rates dropped in all offenders in the 6 months following emotion testing, only the group of offenders who had received the emotion training showed a significant reduction in the severity of the crimes they committed. Conclusions The study indicates that emotion recognition can be relatively easily improved in youths who engage in serious antisocial and criminal behavior. The results suggest that improved emotion recognition has the potential to reduce the severity of reoffending. PMID:26121148

  12. Influence of phenolic compounds on the sensorial perception and volatility of red wine esters in model solution: an insight at the molecular level.

    PubMed

    Lorrain, Bénédicte; Tempere, Sophie; Iturmendi, Nerea; Moine, Virginie; de Revel, Gilles; Teissedre, Pierre-Louis

    2013-09-01

    Impact of (+)-catechin and gallic acid on sensory perception and volatility of isoamyl acetate, ethyl isobutyrate, ethyl butyrate and ethyl octanoate was investigated in model solutions, by means of triangle tests, detection threshold determination and HS-GC-MS analyses. Catechin significantly altered the sensory perception of most esters (ethyl isobutyrate, ethyl butyrate and ethyl octanoate) while gallic acid displayed no impact. Ethyl butyrate and ethyl octanoate odour thresholds doubled or tripled in the presence of catechin, underlining a retention impact of phenolic compounds in liquid matrix. The headspace analyses displayed a decrease only in ethyl octanoate volatility in presence of catechin, whereas no significant difference in other esters concentrations was observed. This study indicated that phenolic compounds have a variable impact on aroma compounds' volatility and their sensory perception. The polarity of phenolic and volatile compounds as well as their spatial conformation also appeared to influence the interaction strength. PMID:23578617

  13. Short-term experiments in using digestate products as substitutes for mineral (N) fertilizer: Agronomic performance, odours, and ammonia emission impacts.

    PubMed

    Riva, C; Orzi, V; Carozzi, M; Acutis, M; Boccasile, G; Lonati, S; Tambone, F; D'Imporzano, G; Adani, F

    2016-03-15

    Anaerobic digestion produces a biologically stable and high-value fertilizer product, the digestate, which can be used as an alternative to mineral fertilizers on crops. However, misuse of digestate can lead to annoyance for the public (odours) and to environmental problems such as nitrate leaching and ammonia emissions into the air. Full field experimental data are needed to support the use of digestate in agriculture, promoting its correct management. In this work, short-term experiments were performed to substitute mineral N fertilizers (urea) with digestate and products derived from it to the crop silage maize. Digestate and the liquid fraction of digestate were applied to soil at pre-sowing and as topdressing fertilizers in comparison with urea, both by surface application and subsurface injection during the cropping seasons 2012 and 2013. After each fertilizer application, both odours and ammonia emissions were measured, giving data about digestate and derived products' impacts. The AD products could substitute for urea without reducing crop yields, apart from the surface application of AD-derived fertilizers. Digestate and derived products, because of high biological stability acquired during the AD, had greatly reduced olfactometry impact, above all when they were injected into soils (82-88% less odours than the untreated biomass, i.e. cattle slurry). Ammonia emission data indicated, as expected, that the correct use of digestate and derived products required their injection into the soil avoiding, ammonia volatilization into the air and preserving fertilizer value. Sub-surface injection allowed ammonia emissions to be reduced by 69% and 77% compared with surface application during the 2012 and 2013 campaigns.

  14. Children's perception of foreign-accented words.

    PubMed

    Bent, Tessa

    2014-11-01

    The acoustic-phonetic realizations of words can vary dramatically depending on a variety of within- and across-talker characteristics such as regional dialect, native language, age, and gender. Robust word learning requires that children are able to recognize words amidst this substantial variability. In the current study, perception of foreign-accented words was assessed in four- to seven-year-old children to test how one form of variability influences word recognition in children. Results demonstrated that children had less accurate word recognition than adults for both native- and foreign-accented words. Both adults and children were less accurate at identifying foreign-accented words compared to native-accented words with children and adults showing similar decrements. For children, age and lexicon size contributed to accurate word recognition.

  15. Auditory perception of a human walker.

    PubMed

    Cottrell, David; Campbell, Megan E J

    2014-01-01

    When one hears footsteps in the hall, one is able to instantly recognise it as a person: this is an everyday example of auditory biological motion perception. Despite the familiarity of this experience, research into this phenomenon is in its infancy compared with visual biological motion perception. Here, two experiments explored sensitivity to, and recognition of, auditory stimuli of biological and nonbiological origin. We hypothesised that the cadence of a walker gives rise to a temporal pattern of impact sounds that facilitates the recognition of human motion from auditory stimuli alone. First a series of detection tasks compared sensitivity with three carefully matched impact sounds: footsteps, a ball bouncing, and drumbeats. Unexpectedly, participants were no more sensitive to footsteps than to impact sounds of nonbiological origin. In the second experiment participants made discriminations between pairs of the same stimuli, in a series of recognition tasks in which the temporal pattern of impact sounds was manipulated to be either that of a walker or the pattern more typical of the source event (a ball bouncing or a drumbeat). Under these conditions, there was evidence that both temporal and nontemporal cues were important in recognising theses stimuli. It is proposed that the interval between footsteps, which reflects a walker's cadence, is a cue for the recognition of the sounds of a human walking.

  16. Face averages enhance user recognition for smartphone security.

    PubMed

    Robertson, David J; Kramer, Robin S S; Burton, A Mike

    2015-01-01

    Our recognition of familiar faces is excellent, and generalises across viewing conditions. However, unfamiliar face recognition is much poorer. For this reason, automatic face recognition systems might benefit from incorporating the advantages of familiarity. Here we put this to the test using the face verification system available on a popular smartphone (the Samsung Galaxy). In two experiments we tested the recognition performance of the smartphone when it was encoded with an individual's 'face-average'--a representation derived from theories of human face perception. This technique significantly improved performance for both unconstrained celebrity images (Experiment 1) and for real faces (Experiment 2): users could unlock their phones more reliably when the device stored an average of the user's face than when they stored a single image. This advantage was consistent across a wide variety of everyday viewing conditions. Furthermore, the benefit did not reduce the rejection of imposter faces. This benefit is brought about solely by consideration of suitable representations for automatic face recognition, and we argue that this is just as important as development of matching algorithms themselves. We propose that this representation could significantly improve recognition rates in everyday settings.

  17. Face Averages Enhance User Recognition for Smartphone Security

    PubMed Central

    Robertson, David J.; Kramer, Robin S. S.; Burton, A. Mike

    2015-01-01

    Our recognition of familiar faces is excellent, and generalises across viewing conditions. However, unfamiliar face recognition is much poorer. For this reason, automatic face recognition systems might benefit from incorporating the advantages of familiarity. Here we put this to the test using the face verification system available on a popular smartphone (the Samsung Galaxy). In two experiments we tested the recognition performance of the smartphone when it was encoded with an individual’s ‘face-average’ – a representation derived from theories of human face perception. This technique significantly improved performance for both unconstrained celebrity images (Experiment 1) and for real faces (Experiment 2): users could unlock their phones more reliably when the device stored an average of the user’s face than when they stored a single image. This advantage was consistent across a wide variety of everyday viewing conditions. Furthermore, the benefit did not reduce the rejection of imposter faces. This benefit is brought about solely by consideration of suitable representations for automatic face recognition, and we argue that this is just as important as development of matching algorithms themselves. We propose that this representation could significantly improve recognition rates in everyday settings. PMID:25807251

  18. Speech Recognition in Natural Background Noise

    PubMed Central

    Meyer, Julien; Dentel, Laure; Meunier, Fanny

    2013-01-01

    In the real world, human speech recognition nearly always involves listening in background noise. The impact of such noise on speech signals and on intelligibility performance increases with the separation of the listener from the speaker. The present behavioral experiment provides an overview of the effects of such acoustic disturbances on speech perception in conditions approaching ecologically valid contexts. We analysed the intelligibility loss in spoken word lists with increasing listener-to-speaker distance in a typical low-level natural background noise. The noise was combined with the simple spherical amplitude attenuation due to distance, basically changing the signal-to-noise ratio (SNR). Therefore, our study draws attention to some of the most basic environmental constraints that have pervaded spoken communication throughout human history. We evaluated the ability of native French participants to recognize French monosyllabic words (spoken at 65.3 dB(A), reference at 1 meter) at distances between 11 to 33 meters, which corresponded to the SNRs most revealing of the progressive effect of the selected natural noise (−8.8 dB to −18.4 dB). Our results showed that in such conditions, identity of vowels is mostly preserved, with the striking peculiarity of the absence of confusion in vowels. The results also confirmed the functional role of consonants during lexical identification. The extensive analysis of recognition scores, confusion patterns and associated acoustic cues revealed that sonorant, sibilant and burst properties were the most important parameters influencing phoneme recognition. . Altogether these analyses allowed us to extract a resistance scale from consonant recognition scores. We also identified specific perceptual consonant confusion groups depending of the place in the words (onset vs. coda). Finally our data suggested that listeners may access some acoustic cues of the CV transition, opening interesting perspectives for future studies

  19. Recognition for Employed Inventors.

    ERIC Educational Resources Information Center

    Sanders, Howard J.

    1980-01-01

    Presents arguments for monetary rewards and other forms of recognition by employers for inventions of employed inventors, particularly as the concept applies to stimulating innovativeness in America. Discusses the controversy of federally mandated compensation for employed inventors. The efforts of the American Chemical Society along these lines…

  20. Units of Word Recognition.

    ERIC Educational Resources Information Center

    Santa, Carol M.; And Others

    Both psychologists and reading specialists have been interested in whether words are processed letter by letter or in larger units. A reaction time paradigm was used to evaluate these options with interest focused on potential units of word recognition which might be functional within single syllable words. The basic paradigm involved presenting…

  1. Optical Character Recognition.

    ERIC Educational Resources Information Center

    Converso, L.; Hocek, S.

    1990-01-01

    This paper describes computer-based optical character recognition (OCR) systems, focusing on their components (the computer, the scanner, the OCR, and the output device); how the systems work; and features to consider in selecting a system. A list of 26 questions to ask to evaluate systems for potential purchase is included. (JDD)

  2. Recognition Memory for Pseudowords

    ERIC Educational Resources Information Center

    Greene, Robert L.

    2004-01-01

    Participants are more likely to give positive responses on a recognition test to pseudowords (pronounceable nonwords) than words. A series of experiments suggests that this difference reflects the greater overall familiarity of pseudowords than of words. Pseudowords receive higher ratings of similarity to a studied list than do words. Pseudowords…

  3. Microprocessor for speech recognition

    SciTech Connect

    Ishizuka, H.; Watari, M.; Sakoe, H.; Chiba, S.; Iwata, T.; Matsuki, T.; Kawakami, Y.

    1983-01-01

    A new single-chip microprocessor for speech recognition has been developed utilizing multi-processor architecture and pipelined structure. By DP-matching algorithm, the processor recognizes up to 340 isolated words or 40 connected words in realtime. 6 references.

  4. 1987 CASE Recognition Awards.

    ERIC Educational Resources Information Center

    Currents, 1987

    1987-01-01

    The 1987 CASE Recognition Awards are presented for: general excellence in programs; student recruitment marketing improvement; video public service announcements, news, and commercial spots; total publications; magazines of the decade; improvement in periodicals; photocommunications via print; designer of the year and series; and imagination in…

  5. Pattern recognition in bioinformatics.

    PubMed

    de Ridder, Dick; de Ridder, Jeroen; Reinders, Marcel J T

    2013-09-01

    Pattern recognition is concerned with the development of systems that learn to solve a given problem using a set of example instances, each represented by a number of features. These problems include clustering, the grouping of similar instances; classification, the task of assigning a discrete label to a given instance; and dimensionality reduction, combining or selecting features to arrive at a more useful representation. The use of statistical pattern recognition algorithms in bioinformatics is pervasive. Classification and clustering are often applied to high-throughput measurement data arising from microarray, mass spectrometry and next-generation sequencing experiments for selecting markers, predicting phenotype and grouping objects or genes. Less explicitly, classification is at the core of a wide range of tools such as predictors of genes, protein function, functional or genetic interactions, etc., and used extensively in systems biology. A course on pattern recognition (or machine learning) should therefore be at the core of any bioinformatics education program. In this review, we discuss the main elements of a pattern recognition course, based on material developed for courses taught at the BSc, MSc and PhD levels to an audience of bioinformaticians, computer scientists and life scientists. We pay attention to common problems and pitfalls encountered in applications and in interpretation of the results obtained.

  6. Prediction, Bayesian inference and feedback in speech recognition

    PubMed Central

    Norris, Dennis; McQueen, James M.; Cutler, Anne

    2016-01-01

    ABSTRACT Speech perception involves prediction, but how is that prediction implemented? In cognitive models prediction has often been taken to imply that there is feedback of activation from lexical to pre-lexical processes as implemented in interactive-activation models (IAMs). We show that simple activation feedback does not actually improve speech recognition. However, other forms of feedback can be beneficial. In particular, feedback can enable the listener to adapt to changing input, and can potentially help the listener to recognise unusual input, or recognise speech in the presence of competing sounds. The common feature of these helpful forms of feedback is that they are all ways of optimising the performance of speech recognition using Bayesian inference. That is, listeners make predictions about speech because speech recognition is optimal in the sense captured in Bayesian models. PMID:26740960

  7. Beginning Students' Perceptions of Effective Activities for Chinese Character Recognition

    ERIC Educational Resources Information Center

    Wang, Jing; Leland, Christine H.

    2011-01-01

    This study investigates what beginning learners of Chinese perceive as helpful in learning to recognize characters. Thirteen English-speaking participants in a beginning Chinese class answered journal questions and completed a survey over one semester at a large Midwestern university. Findings suggest that participants perceived the usefulness of…

  8. Supporting Quality Teachers with Recognition

    ERIC Educational Resources Information Center

    Andrews, Hans A.

    2011-01-01

    Value has been found in providing recognition and awards programs for excellent teachers. Research has also found a major lack of these programs in both the USA and in Australia. Teachers receiving recognition and awards for their teaching have praised recognition programs as providing motivation for them to continue high-level instruction.…

  9. Word Recognition in Auditory Cortex

    ERIC Educational Resources Information Center

    DeWitt, Iain D. J.

    2013-01-01

    Although spoken word recognition is more fundamental to human communication than text recognition, knowledge of word-processing in auditory cortex is comparatively impoverished. This dissertation synthesizes current models of auditory cortex, models of cortical pattern recognition, models of single-word reading, results in phonetics and results in…

  10. Visual Recognition Memory across Contexts

    ERIC Educational Resources Information Center

    Jones, Emily J. H.; Pascalis, Olivier; Eacott, Madeline J.; Herbert, Jane S.

    2011-01-01

    In two experiments, we investigated the development of representational flexibility in visual recognition memory during infancy using the Visual Paired Comparison (VPC) task. In Experiment 1, 6- and 9-month-old infants exhibited recognition when familiarization and test occurred in the same room, but showed no evidence of recognition when…

  11. A dissonant scale: stress recognition in the SAQ

    PubMed Central

    2013-01-01

    Background Our previous analyses using the Stress Recognition subscale of the Safety Attitudes Questionnaire (SAQ) resulted in significant effect estimates with equally opposing explanations. We suspected construct validity issues and investigated such using our own data and correlation matrices of previous published studies. Methods The correlation matrices for each of the SAQ subscales from two previous studies by Speroff and Taylor were replicated and compared. The SAS Proc Factor procedure and the PRIORS = SMC option were used to perform Common Factor Analysis. Results The correlation matrices of both studies were very similar. Teamwork, Safety Climate, Job Satisfaction, Perceptions of Management and Working Conditions were well-correlated. The correlations ranged from 0.53 to 0.76. For Stress Recognition correlations ranged from -0.15 to 0.03. Common Factor Analysis confirmed the isolation of Stress Recognition. CFA returned a strong one-factor model that explained virtually all of the communal variance. Stress Recognition loaded poorly on this factor in both instances, and the CFA indicated that 96.4-100.0% of the variance associated with Stress Recognition was unique to that subscale, and not shared with the other 5 subscales. Conclusions We conclude that the Stress Recognition subscale does not fit into the overall safety climate construct the SAQ intended to reflect. We recommend that this domain be omitted from overall safety climate scale score calculations, and clearly identified as an important yet distinct organizational construct. We suggest that this subscale be investigated for its true meaning, characterized as such, and findings conveyed to SAQ end users. We make no argument against Stress Recognition as an important organizational metric, rather we suggest that as a stand-alone construct its current packaging within the SAQ may be misleading for those intent on intervention development and evaluation in healthcare settings if they interpret

  12. Neural mechanisms of face perception, their emergence over development, and their breakdown.

    PubMed

    Behrmann, Marlene; Scherf, K Suzanne; Avidan, Galia

    2016-07-01

    Face perception is probably the most developed visual perceptual skill in humans, most likely as a result of its unique evolutionary and social significance. Much recent research has converged to identify a host of relevant psychological mechanisms that support face recognition. In parallel, there has been substantial progress in uncovering the neural mechanisms that mediate rapid and accurate face perception, with specific emphasis on a broadly distributed neural circuit, comprised of multiple nodes whose joint activity supports face perception. This article focuses specifically on the neural underpinnings of face recognition, and reviews recent structural and functional imaging studies that elucidate the neural basis of this ability. In addition, the article covers some of the recent investigations that characterize the emergence of the neural basis of face recognition over the course of development, and explores the relationship between these changes and increasing behavioural competence. This paper also describes studies that characterize the nature of the breakdown of face recognition in individuals who are impaired in face recognition, either as a result of brain damage acquired at some point or as a result of the failure to master face recognition over the course of development. Finally, information regarding similarities between the neural circuits for face perception in humans and in nonhuman primates is briefly covered, as is the contribution of subcortical regions to face perception. WIREs Cogn Sci 2016, 7:247-263. doi: 10.1002/wcs.1388 For further resources related to this article, please visit the WIREs website. PMID:27196333

  13. Research on Speech Perception. Progress Report No. 12.

    ERIC Educational Resources Information Center

    Pisoni, David B.; And Others

    Summarizing research activities in 1986, this is the twelfth annual report of research on speech perception, analysis, synthesis, and recognition conducted in the Speech Research Laboratory of the Department of Psychology at Indiana University. The report contains the following 23 articles: "Comprehension of Digitally Encoded Natural Speech Using…

  14. Perception of Biological Motion in Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Freitag, Christine M.; Konrad, Carsten; Haberlen, Melanie; Kleser, Christina; von Gontard, Alexander; Reith, Wolfgang; Troje, Nikolaus F.; Krick, Christoph

    2008-01-01

    In individuals with autism or autism-spectrum-disorder (ASD), conflicting results have been reported regarding the processing of biological motion tasks. As biological motion perception and recognition might be related to impaired imitation, gross motor skills and autism specific psychopathology in individuals with ASD, we performed a functional…

  15. Research on Speech Perception. Progress Report No. 15.

    ERIC Educational Resources Information Center

    Pisoni, David B.

    Summarizing research activities in 1989, this is the fifteenth annual report of research on speech perception, analysis, synthesis, and recognition conducted in the Speech Research Laboratory of the Department of Psychology at Indiana University. The report contains the following 21 articles: "Perceptual Learning of Nonnative Speech Contrasts:…

  16. Research on Speech Perception. Progress Report No. 14.

    ERIC Educational Resources Information Center

    Pisoni, David B.; And Others

    Summarizing research activities in 1988, this is the fourteenth annual report of research on speech perception, analysis, synthesis, and recognition conducted in the Speech Research Laboratory of the Department of Psychology at Indiana University. The report includes extended manuscripts, short reports, and progress reports. The report contains…

  17. Recognition of Teaching Excellence*

    PubMed Central

    Piascik, Peggy; Medina, Melissa; Pittenger, Amy; Rose, Renee; Creekmore, Freddy; Soltis, Robert; Bouldin, Alicia; Schwarz, Lindsay; Scott, Steven

    2010-01-01

    The 2008-2009 Task Force for the Recognition of Teaching Excellence was charged by the AACP Council of Faculties Leadership to examine teaching excellence by collecting best practices from colleges and schools of pharmacy, evaluating the literature to identify evidence-based criteria for excellent teaching, and recommending appropriate means to acknowledge and reward teaching excellence. This report defines teaching excellence and discusses a variety of ways to assess it, including student, alumni, peer, and self-assessment. The task force identifies important considerations that colleges and schools must address when establishing teaching recognition programs including the purpose, criteria, number and mix of awards, frequency, type of award, and method of nominating and determining awardees. The report concludes with recommendations for the academy to consider when establishing and revising teaching award programs. PMID:21301598

  18. Recognition of teaching excellence.

    PubMed

    Hammer, Dana; Piascik, Peggy; Medina, Melissa; Pittenger, Amy; Rose, Renee; Creekmore, Freddy; Soltis, Robert; Bouldin, Alicia; Schwarz, Lindsay; Scott, Steven

    2010-11-10

    The 2008-2009 Task Force for the Recognition of Teaching Excellence was charged by the AACP Council of Faculties Leadership to examine teaching excellence by collecting best practices from colleges and schools of pharmacy, evaluating the literature to identify evidence-based criteria for excellent teaching, and recommending appropriate means to acknowledge and reward teaching excellence. This report defines teaching excellence and discusses a variety of ways to assess it, including student, alumni, peer, and self-assessment. The task force identifies important considerations that colleges and schools must address when establishing teaching recognition programs including the purpose, criteria, number and mix of awards, frequency, type of award, and method of nominating and determining awardees. The report concludes with recommendations for the academy to consider when establishing and revising teaching award programs.

  19. Audio-visual gender recognition

    NASA Astrophysics Data System (ADS)

    Liu, Ming; Xu, Xun; Huang, Thomas S.

    2007-11-01

    Combining different modalities for pattern recognition task is a very promising field. Basically, human always fuse information from different modalities to recognize object and perform inference, etc. Audio-Visual gender recognition is one of the most common task in human social communication. Human can identify the gender by facial appearance, by speech and also by body gait. Indeed, human gender recognition is a multi-modal data acquisition and processing procedure. However, computational multimodal gender recognition has not been extensively investigated in the literature. In this paper, speech and facial image are fused to perform a mutli-modal gender recognition for exploring the improvement of combining different modalities.

  20. Phrasing influences the recognition of melodies.

    PubMed

    Chiappe, P; Schmuckler, M A

    1997-06-01

    One critical step in the processing of complex auditory information (i.e., language and music) involves organizing such information into hierarchical units, such as phrases. In this study, musically trained and untrained listeners' recognition memory for short, naturalistic melodies varying in their phrase structure was tested. For musically trained subjects, memory for information preceding a phrase boundary was disrupted and memory for information subsequent to a phrase boundary was enhanced relative to memory in similar temporal locations for excerpts not containing a phrase boundary. Musically untrained listeners, in contrast, showed no such differences as a function of the phrasing of the melody. These findings conform with previous results in both psycholinguistics and musical cognition and suggest that the phrase serves as a functional unit in musical processing, guiding the parsing of musical sequences during perception, along with the structuring of memory for musical passages. PMID:21331834

  1. Famous talker effects in spoken word recognition.

    PubMed

    Maibauer, Alisa M; Markis, Teresa A; Newell, Jessica; McLennan, Conor T

    2014-01-01

    Previous work has demonstrated that talker-specific representations affect spoken word recognition relatively late during processing. However, participants in these studies were listening to unfamiliar talkers. In the present research, we used a long-term repetition-priming paradigm and a speeded-shadowing task and presented listeners with famous talkers. In Experiment 1, half the words were spoken by Barack Obama, and half by Hillary Clinton. Reaction times (RTs) to repeated words were shorter than those to unprimed words only when repeated by the same talker. However, in Experiment 2, using nonfamous talkers, RTs to repeated words were shorter than those to unprimed words both when repeated by the same talker and when repeated by a different talker. Taken together, the results demonstrate that talker-specific details can affect the perception of spoken words relatively early during processing when words are spoken by famous talkers.

  2. The recognition potential and word priming.

    PubMed

    Rudell, A P; Hua, J

    1996-11-01

    The effect of priming on the latency of the recognition potential (RP) was tested using rapid stream stimulation. Subjects detected five-letter words in a stream of nonword images. Lifting the right index finger signalled detection of a word. Rapid responses were rewarded and false alarms were penalized. Just before generating an image stream, a computer briefly displayed either the specific target word or or five-letter string that indicated the target was any one of ten previously studied words. Precise target specification was expected to produce more rapid detection than the provision of less definite information. Since the RP was thought to reflect the speed of perception, it was predicted that its latency would be less when the target word was beforehand than when less specific information was provided. The results for 10 subjects confirmed the hypothesis.

  3. Famous talker effects in spoken word recognition.

    PubMed

    Maibauer, Alisa M; Markis, Teresa A; Newell, Jessica; McLennan, Conor T

    2014-01-01

    Previous work has demonstrated that talker-specific representations affect spoken word recognition relatively late during processing. However, participants in these studies were listening to unfamiliar talkers. In the present research, we used a long-term repetition-priming paradigm and a speeded-shadowing task and presented listeners with famous talkers. In Experiment 1, half the words were spoken by Barack Obama, and half by Hillary Clinton. Reaction times (RTs) to repeated words were shorter than those to unprimed words only when repeated by the same talker. However, in Experiment 2, using nonfamous talkers, RTs to repeated words were shorter than those to unprimed words both when repeated by the same talker and when repeated by a different talker. Taken together, the results demonstrate that talker-specific details can affect the perception of spoken words relatively early during processing when words are spoken by famous talkers. PMID:24366633

  4. The changing of the guard: the Pto/Prf receptor complex of tomato and pathogen recognition.

    PubMed

    Ntoukakis, Vardis; Saur, Isabel M L; Conlan, Brendon; Rathjen, John P

    2014-08-01

    One important model for disease resistance is the Prf recognition complex of tomato, which responds to different bacterial effectors. Prf incorporates a protein kinase called Pto as its recognition domain that mimics effector virulence targets, and activates resistance after interaction with specific effectors. Recent findings show that this complex is oligomeric, and reveal how this impacts mechanism. Oligomerisation brings two or more kinases into proximity, where they can phosphorylate each other after effector perception. Effector attack on one kinase activates another in trans, constituting a molecular trap for the effector. Oligomerisation of plant resistance proteins may be a general concept that broadens pathogen recognition and restricts the ability of pathogens to evolve virulence.

  5. The Production and Recognition of Acoustic Frequency Cues in Chickadees

    NASA Astrophysics Data System (ADS)

    Lohr, Bernard Stephen

    1995-01-01

    The production and recognition of songs with appropriate species-typical features underlies a songbird's success in defending a breeding territory. The ability to recognize a song that is characteristic of one's own species presents an interesting problem, given the variety of types of information often encoded in song. Information in song may involve cues for individual identity, neighbor/stranger recognition, reproductive status, and motivational state. This thesis is concerned with the use of acoustic frequency as a cue for species-recognition of birdsong, and the various forms of frequency production and perception that may provide such cues. Carolina chickadees (Parus carolinensis) sing songs characterized by a succession of unmodulated, pure -tonal notes that alternate between high (approximately 5400-7000 Hz) and low (approximately 3000-4200 Hz) frequencies. Mechanisms of acoustic frequency perception in male territorial Carolina chickadees were evaluated using playback experiments designed to vary specific note frequencies, note frequency ranges, and the frequency range of the entire song type. Note frequency ranges provide the primary acoustic frequency cues for song recognition in this species. A gap between note frequency ranges exists in this species. Tones in this intermediate frequency range do not receive responses in the context of territorial song recognition. This kind of gap in frequency perception has not been demonstrated for other songbirds. Song playback experiments also were designed to vary systematically the contours (inter-note frequency sequences) of notes in song. Note frequency ranges provide the principal cues for song recognition, while the contour between note frequencies plays a supplementary role. The presence of a single descending interval between notes in the appropriate note frequency ranges of Carolina chickadee song generates full species-typical responses to song. Additionally, response to a descending contour between note

  6. Including public perception data in the evaluation of the consequences of sewerage derived urban flooding.

    PubMed

    Arthur, Scott; Crow, Helen; Karikas, Naoum

    2009-01-01

    This text reports research which was undertaken to assess the failure consequences associated with sewerage systems. In an effort to move away from considering only flood volume, depth or extent, the text will focus on how a survey of public opinion was used to inform the development of a consequence scoring methodology. The failure consequences considered range from internal flooding of properties, to road closure, environmental damage and odour problems. The text reports the extent to which experience of flooding influences perceptions of failure consequence and sewerage system management. It is also outlined how this data was used, along with other data sources, to construct an objective scoring process that can be used to evaluate failure consequence and readily prioritise sewerage maintenance.

  7. Facial and bodily emotion recognition in multiple sclerosis: the role of alexithymia and other characteristics of the disease.

    PubMed

    Cecchetto, Cinzia; Aiello, Marilena; D'Amico, Delia; Cutuli, Daniela; Cargnelutti, Daniela; Eleopra, Roberto; Rumiati, Raffaella Ida

    2014-11-01

    Multiple sclerosis (MS) may be associated with impaired perception of facial emotions. However, emotion recognition mediated by bodily postures has never been examined in these patients. Moreover, several studies have suggested a relation between emotion recognition impairments and alexithymia. This is in line with the idea that the ability to recognize emotions requires the individuals to be able to understand their own emotions. Despite a deficit in emotion recognition has been observed in MS patients, the association between impaired emotion recognition and alexithymia has received little attention. The aim of this study was, first, to investigate MS patient's abilities to recognize emotions mediated by both facial and bodily expressions and, second, to examine whether any observed deficits in emotions recognition could be explained by the presence of alexithymia. Thirty patients with MS and 30 healthy matched controls performed experimental tasks assessing emotion discrimination and recognition of facial expressions and bodily postures. Moreover, they completed questionnaires evaluating alexithymia, depression, and fatigue. First, facial emotion recognition and, to a lesser extent, bodily emotion recognition can be impaired in MS patients. In particular, patients with higher disability showed an impairment in emotion recognition compared with patients with lower disability and controls. Second, their deficit in emotion recognition was not predicted by alexithymia. Instead, the disease's characteristics and the performance on some cognitive tasks significantly correlated with emotion recognition. Impaired facial emotion recognition is a cognitive signature of MS that is not dependent on alexithymia.

  8. Relationship between multipulse integration and speech recognition with cochlear implants

    PubMed Central

    Zhou, Ning; Pfingst, Bryan E.

    2014-01-01

    Comparisons of performance with cochlear implants and postmortem conditions in the cochlea in humans have shown mixed results. The limitations in those studies favor the use of within-subject designs and non-invasive measures to estimate cochlear conditions. One non-invasive correlate of cochlear health is multipulse integration, established in an animal model. The present study used this measure to relate neural health in human cochlear implant users to their speech recognition performance. The multipulse-integration slopes were derived based on psychophysical detection thresholds measured for two pulse rates (80 and 640 pulses per second). A within-subject design was used in eight subjects with bilateral implants where the direction and magnitude of ear differences in the multipulse-integration slopes were compared with those of the speech-recognition results. The speech measures included speech reception threshold for sentences and phoneme recognition in noise. The magnitude of ear difference in the integration slopes was significantly correlated with the magnitude of ear difference in speech reception thresholds, consonant recognition in noise, and transmission of place of articulation of consonants. These results suggest that multipulse integration predicts speech recognition in noise and perception of features that use dynamic spectral cues. PMID:25190399

  9. Songbirds use spectral shape, not pitch, for sound pattern recognition.

    PubMed

    Bregman, Micah R; Patel, Aniruddh D; Gentner, Timothy Q

    2016-02-01

    Humans easily recognize "transposed" musical melodies shifted up or down in log frequency. Surprisingly, songbirds seem to lack this capacity, although they can learn to recognize human melodies and use complex acoustic sequences for communication. Decades of research have led to the widespread belief that songbirds, unlike humans, are strongly biased to use absolute pitch (AP) in melody recognition. This work relies almost exclusively on acoustically simple stimuli that may belie sensitivities to more complex spectral features. Here, we investigate melody recognition in a species of songbird, the European Starling (Sturnus vulgaris), using tone sequences that vary in both pitch and timbre. We find that small manipulations altering either pitch or timbre independently can drive melody recognition to chance, suggesting that both percepts are poor descriptors of the perceptual cues used by birds for this task. Instead we show that melody recognition can generalize even in the absence of pitch, as long as the spectral shapes of the constituent tones are preserved. These results challenge conventional views regarding the use of pitch cues in nonhuman auditory sequence recognition. PMID:26811447

  10. Culture moderates the relationship between interdependence and face recognition

    PubMed Central

    Ng, Andy H.; Steele, Jennifer R.; Sasaki, Joni Y.; Sakamoto, Yumiko; Williams, Amanda

    2015-01-01

    Recent theory suggests that face recognition accuracy is affected by people’s motivations, with people being particularly motivated to remember ingroup versus outgroup faces. In the current research we suggest that those higher in interdependence should have a greater motivation to remember ingroup faces, but this should depend on how ingroups are defined. To examine this possibility, we used a joint individual difference and cultural approach to test (a) whether individual differences in interdependence would predict face recognition accuracy, and (b) whether this effect would be moderated by culture. In Study 1 European Canadians higher in interdependence demonstrated greater recognition for same-race (White), but not cross-race (East Asian) faces. In Study 2 we found that culture moderated this effect. Interdependence again predicted greater recognition for same-race (White), but not cross-race (East Asian) faces among European Canadians; however, interdependence predicted worse recognition for both same-race (East Asian) and cross-race (White) faces among first-generation East Asians. The results provide insight into the role of motivation in face perception as well as cultural differences in the conception of ingroups. PMID:26579011

  11. Songbirds use spectral shape, not pitch, for sound pattern recognition

    PubMed Central

    Bregman, Micah R.; Patel, Aniruddh D.; Gentner, Timothy Q.

    2016-01-01

    Humans easily recognize “transposed” musical melodies shifted up or down in log frequency. Surprisingly, songbirds seem to lack this capacity, although they can learn to recognize human melodies and use complex acoustic sequences for communication. Decades of research have led to the widespread belief that songbirds, unlike humans, are strongly biased to use absolute pitch (AP) in melody recognition. This work relies almost exclusively on acoustically simple stimuli that may belie sensitivities to more complex spectral features. Here, we investigate melody recognition in a species of songbird, the European Starling (Sturnus vulgaris), using tone sequences that vary in both pitch and timbre. We find that small manipulations altering either pitch or timbre independently can drive melody recognition to chance, suggesting that both percepts are poor descriptors of the perceptual cues used by birds for this task. Instead we show that melody recognition can generalize even in the absence of pitch, as long as the spectral shapes of the constituent tones are preserved. These results challenge conventional views regarding the use of pitch cues in nonhuman auditory sequence recognition. PMID:26811447

  12. Songbirds use spectral shape, not pitch, for sound pattern recognition.

    PubMed

    Bregman, Micah R; Patel, Aniruddh D; Gentner, Timothy Q

    2016-02-01

    Humans easily recognize "transposed" musical melodies shifted up or down in log frequency. Surprisingly, songbirds seem to lack this capacity, although they can learn to recognize human melodies and use complex acoustic sequences for communication. Decades of research have led to the widespread belief that songbirds, unlike humans, are strongly biased to use absolute pitch (AP) in melody recognition. This work relies almost exclusively on acoustically simple stimuli that may belie sensitivities to more complex spectral features. Here, we investigate melody recognition in a species of songbird, the European Starling (Sturnus vulgaris), using tone sequences that vary in both pitch and timbre. We find that small manipulations altering either pitch or timbre independently can drive melody recognition to chance, suggesting that both percepts are poor descriptors of the perceptual cues used by birds for this task. Instead we show that melody recognition can generalize even in the absence of pitch, as long as the spectral shapes of the constituent tones are preserved. These results challenge conventional views regarding the use of pitch cues in nonhuman auditory sequence recognition.

  13. Perception of risks.

    PubMed

    Renn, Ortwin

    2004-04-01

    Health and environmental scientists, professional risk managers and the general public strongly disagree about the seriousness of many risks. Most members of the public are concerned about long-term effects of risks, equity and fairness issues, lack of personal control, and the pace of technological diffusion into their cultural environment, whereas professional toxicologists and risk managers focus on the task to minimize the probability of adverse effects caused by a potentially hazardous agent or activity. To bridge the gap between the professional mandate and the public perception of risk, two-way communication has to be initiated between scientists, risk managers, interest groups, and representatives of the affected public. This dialogue should serve three major functions:to facilitate understanding of different risk perspectives among scientists, regulators and stakeholders as well as groups of the public; to enlighten all these constituencies about different rationales for dealing with toxicological risks; to develop appropriate procedures for conflict resolution. A prerequisite for a successful communication is the willingness of each group to respect the perspective of all the other participating groups and to include their concerns into the decision making process. The conference paper reviews the literature on the three main functions of risk communication: message recognition, mutual understanding and respect as a prerequisite for trust building and resolution of risk-related conflicts. The paper discusses the structure of the communication process from a descriptive and a normative point of view and draws on empirical studies about risk perception and communication. The argument will be made that risk cannot be understood as a monolithic concept that penetrates different research disciplines and risk management camps. Risk should rather be seen as a mental instrument that allows prediction of future hazards and facilitates risk reduction measures. Due

  14. A reciprocal model of face recognition and autistic traits: evidence from an individual differences perspective.

    PubMed

    Halliday, Drew W R; MacDonald, Stuart W S; Scherf, K Suzanne; Sherf, Suzanne K; Tanaka, James W

    2014-01-01

    Although not a core symptom of the disorder, individuals with autism often exhibit selective impairments in their face processing abilities. Importantly, the reciprocal connection between autistic traits and face perception has rarely been examined within the typically developing population. In this study, university participants from the social sciences, physical sciences, and humanities completed a battery of measures that assessed face, object and emotion recognition abilities, general perceptual-cognitive style, and sub-clinical autistic traits (the Autism Quotient (AQ)). We employed separate hierarchical multiple regression analyses to evaluate which factors could predict face recognition scores and AQ scores. Gender, object recognition performance, and AQ scores predicted face recognition behaviour. Specifically, males, individuals with more autistic traits, and those with lower object recognition scores performed more poorly on the face recognition test. Conversely, university major, gender and face recognition performance reliably predicted AQ scores. Science majors, males, and individuals with poor face recognition skills showed more autistic-like traits. These results suggest that the broader autism phenotype is associated with lower face recognition abilities, even among typically developing individuals.

  15. Impact of Childhood Maltreatment on the Recognition of Facial Expressions of Emotions.

    PubMed

    Ardizzi, Martina; Martini, Francesca; Umiltà, Maria Alessandra; Evangelista, Valentina; Ravera, Roberto; Gallese, Vittorio

    2015-01-01

    The development of the explicit recognition of facial expressions of emotions can be affected by childhood maltreatment experiences. A previous study demonstrated the existence of an explicit recognition bias for angry facial expressions among a population of adolescent Sierra Leonean street-boys exposed to high levels of maltreatment. In the present study, the recognition bias for angry facial expressions was investigated in a younger population of street-children and age-matched controls. Participants performed a forced-choice facial expressions recognition task. Recognition bias was measured as participants' tendency to over-attribute anger label to other negative facial expressions. Participants' heart rate was assessed and related to their behavioral performance, as index of their stress-related physiological responses. Results demonstrated the presence of a recognition bias for angry facial expressions among street-children, also pinpointing a similar, although significantly less pronounced, tendency among controls. Participants' performance was controlled for age, cognitive and educational levels and for naming skills. None of these variables influenced the recognition bias for angry facial expressions. Differently, a significant effect of heart rate on participants' tendency to use anger label was evidenced. Taken together, these results suggest that childhood exposure to maltreatment experiences amplifies children's "pre-existing bias" for anger labeling in forced-choice emotion recognition task. Moreover, they strengthen the thesis according to which the recognition bias for angry facial expressions is a manifestation of a functional adaptive mechanism that tunes victim's perceptive and attentive focus on salient environmental social stimuli. PMID:26509890

  16. Impact of Childhood Maltreatment on the Recognition of Facial Expressions of Emotions.

    PubMed

    Ardizzi, Martina; Martini, Francesca; Umiltà, Maria Alessandra; Evangelista, Valentina; Ravera, Roberto; Gallese, Vittorio

    2015-01-01

    The development of the explicit recognition of facial expressions of emotions can be affected by childhood maltreatment experiences. A previous study demonstrated the existence of an explicit recognition bias for angry facial expressions among a population of adolescent Sierra Leonean street-boys exposed to high levels of maltreatment. In the present study, the recognition bias for angry facial expressions was investigated in a younger population of street-children and age-matched controls. Participants performed a forced-choice facial expressions recognition task. Recognition bias was measured as participants' tendency to over-attribute anger label to other negative facial expressions. Participants' heart rate was assessed and related to their behavioral performance, as index of their stress-related physiological responses. Results demonstrated the presence of a recognition bias for angry facial expressions among street-children, also pinpointing a similar, although significantly less pronounced, tendency among controls. Participants' performance was controlled for age, cognitive and educational levels and for naming skills. None of these variables influenced the recognition bias for angry facial expressions. Differently, a significant effect of heart rate on participants' tendency to use anger label was evidenced. Taken together, these results suggest that childhood exposure to maltreatment experiences amplifies children's "pre-existing bias" for anger labeling in forced-choice emotion recognition task. Moreover, they strengthen the thesis according to which the recognition bias for angry facial expressions is a manifestation of a functional adaptive mechanism that tunes victim's perceptive and attentive focus on salient environmental social stimuli.

  17. A reciprocal model of face recognition and autistic traits: evidence from an individual differences perspective.

    PubMed

    Halliday, Drew W R; MacDonald, Stuart W S; Scherf, K Suzanne; Sherf, Suzanne K; Tanaka, James W

    2014-01-01

    Although not a core symptom of the disorder, individuals with autism often exhibit selective impairments in their face processing abilities. Importantly, the reciprocal connection between autistic traits and face perception has rarely been examined within the typically developing population. In this study, university participants from the social sciences, physical sciences, and humanities completed a battery of measures that assessed face, object and emotion recognition abilities, general perceptual-cognitive style, and sub-clinical autistic traits (the Autism Quotient (AQ)). We employed separate hierarchical multiple regression analyses to evaluate which factors could predict face recognition scores and AQ scores. Gender, object recognition performance, and AQ scores predicted face recognition behaviour. Specifically, males, individuals with more autistic traits, and those with lower object recognition scores performed more poorly on the face recognition test. Conversely, university major, gender and face recognition performance reliably predicted AQ scores. Science majors, males, and individuals with poor face recognition skills showed more autistic-like traits. These results suggest that the broader autism phenotype is associated with lower face recognition abilities, even among typically developing individuals. PMID:24853862

  18. A Reciprocal Model of Face Recognition and Autistic Traits: Evidence from an Individual Differences Perspective

    PubMed Central

    Halliday, Drew W. R.; MacDonald, Stuart W. S.; Sherf, Suzanne K.; Tanaka, James W.

    2014-01-01

    Although not a core symptom of the disorder, individuals with autism often exhibit selective impairments in their face processing abilities. Importantly, the reciprocal connection between autistic traits and face perception has rarely been examined within the typically developing population. In this study, university participants from the social sciences, physical sciences, and humanities completed a battery of measures that assessed face, object and emotion recognition abilities, general perceptual-cognitive style, and sub-clinical autistic traits (the Autism Quotient (AQ)). We employed separate hierarchical multiple regression analyses to evaluate which factors could predict face recognition scores and AQ scores. Gender, object recognition performance, and AQ scores predicted face recognition behaviour. Specifically, males, individuals with more autistic traits, and those with lower object recognition scores performed more poorly on the face recognition test. Conversely, university major, gender and face recognition performance reliably predicted AQ scores. Science majors, males, and individuals with poor face recognition skills showed more autistic-like traits. These results suggest that the broader autism phenotype is associated with lower face recognition abilities, even among typically developing individuals. PMID:24853862

  19. Emotions affect the recognition of hand gestures

    PubMed Central

    Vicario, Carmelo M.; Newman, Anica

    2013-01-01

    The body is closely tied to the processing of social and emotional information. The purpose of this study was to determine whether a relationship between emotions and social attitudes conveyed through gestures exists. Thus, we tested the effect of pro-social (i.e., happy face) and anti-social (i.e., angry face) emotional primes on the ability to detect socially relevant hand postures (i.e., pictures depicting an open/closed hand). In particular, participants were required to establish, as quickly as possible, if the test stimulus (i.e., a hand posture) was the same or different, compared to the reference stimulus (i.e., a hand posture) previously displayed in the computer screen. Results show that facial primes, displayed between the reference and the test stimuli, influence the recognition of hand postures, according to the social attitude implicitly related to the stimulus. We found that perception of pro-social (i.e., happy face) primes resulted in slower RTs in detecting the open hand posture as compared to the closed hand posture. Vice-versa, perception of the anti-social (i.e., angry face) prime resulted in slower RTs in detecting the closed hand posture compared to the open hand posture. These results suggest that the social attitude implicitly conveyed by the displayed stimuli might represent the conceptual link between emotions and gestures. PMID:24421763

  20. Spoken word recognition without a TRACE

    PubMed Central

    Hannagan, Thomas; Magnuson, James S.; Grainger, Jonathan

    2013-01-01

    How do we map the rapid input of spoken language onto phonological and lexical representations over time? Attempts at psychologically-tractable computational models of spoken word recognition tend either to ignore time or to transform the temporal input into a spatial representation. TRACE, a connectionist model with broad and deep coverage of speech perception and spoken word recognition phenomena, takes the latter approach, using exclusively time-specific units at every level of representation. TRACE reduplicates featural, phonemic, and lexical inputs at every time step in a large memory trace, with rich interconnections (excitatory forward and backward connections between levels and inhibitory links within levels). As the length of the memory trace is increased, or as the phoneme and lexical inventory of the model is increased to a realistic size, this reduplication of time- (temporal position) specific units leads to a dramatic proliferation of units and connections, begging the question of whether a more efficient approach is possible. Our starting point is the observation that models of visual object recognition—including visual word recognition—have grappled with the problem of spatial invariance, and arrived at solutions other than a fully-reduplicative strategy like that of TRACE. This inspires a new model of spoken word recognition that combines time-specific phoneme representations similar to those in TRACE with higher-level representations based on string kernels: temporally independent (time invariant) diphone and lexical units. This reduces the number of necessary units and connections by several orders of magnitude relative to TRACE. Critically, we compare the new model to TRACE on a set of key phenomena, demonstrating that the new model inherits much of the behavior of TRACE and that the drastic computational savings do not come at the cost of explanatory power. PMID:24058349

  1. Infant word recognition: Insights from TRACE simulations☆

    PubMed Central

    Mayor, Julien; Plunkett, Kim

    2014-01-01

    The TRACE model of speech perception (McClelland & Elman, 1986) is used to simulate results from the infant word recognition literature, to provide a unified, theoretical framework for interpreting these findings. In a first set of simulations, we demonstrate how TRACE can reconcile apparently conflicting findings suggesting, on the one hand, that consonants play a pre-eminent role in lexical acquisition (Nespor, Peña & Mehler, 2003; Nazzi, 2005), and on the other, that there is a symmetry in infant sensitivity to vowel and consonant mispronunciations of familiar words (Mani & Plunkett, 2007). In a second series of simulations, we use TRACE to simulate infants’ graded sensitivity to mispronunciations of familiar words as reported by White and Morgan (2008). An unexpected outcome is that TRACE fails to demonstrate graded sensitivity for White and Morgan’s stimuli unless the inhibitory parameters in TRACE are substantially reduced. We explore the ramifications of this finding for theories of lexical development. Finally, TRACE mimics the impact of phonological neighbourhoods on early word learning reported by Swingley and Aslin (2007). TRACE offers an alternative explanation of these findings in terms of mispronunciations of lexical items rather than imputing word learning to infants. Together these simulations provide an evaluation of Developmental (Jusczyk, 1993) and Familiarity (Metsala, 1999) accounts of word recognition by infants and young children. The findings point to a role for both theoretical approaches whereby vocabulary structure and content constrain infant word recognition in an experience-dependent fashion, and highlight the continuity in the processes and representations involved in lexical development during the second year of life. PMID:24493907

  2. Urban Australians using recycled water for domestic non-potable use--an evaluation of the attributes price, saltiness, colour and odour using conjoint analysis.

    PubMed

    Hurlimann, Anna; McKay, Jennifer

    2007-04-01

    Recycled water use in urban areas is viewed as one part of the solution to Australia's water shortage. The effectiveness of policies designed to promote recycled water systems depends on the acceptance by the community of the price, colour, odour and salt content of the recycled water. In Australia and other countries, limited research has been conducted that investigates community attitudes to and willingness to pay for recycled water, especially in urban settings. Community acceptance of recycled water and the economic feasibility of such projects have not been widely evaluated, even though the long-term feasibility of many projects is dependent on such information. This paper examines the attitudes of an urban Australian community living at Mawson Lakes in South Australia, to using recycled water for non-potable domestic purposes. Conjoint analysis (CA) was used to evaluate participant's (n=136) preferences for various attributes of recycled water (colour, odour, salt content and price) for various uses (garden watering, toilet flushing and clothes washing). The analysis was used to estimate the respondent's willingness to pay (WTP) for quality increases for each of the attributes. Differences in WTP were investigated according to various demographic variables including income and education. Results indicate that for garden watering having 'low salt levels' is the most important attribute of recycled water, for clothes washing 'colourless' is the most important attribute, and for toilet flushing a 'low price' was the most important attribute. Respondents were willing to pay for increases in the quality of recycled water. The amount they were willing to pay varied depending on applied use and the attribute in question. Respondents were most willing to pay for an increase in quality of recycled water when used for clothes washing (willing to pay Australian dollars (A$) 0.07/cubic meter (m(3)) for removal of colour, A$0.065 per cubic meter for an increase in

  3. Smart pattern recognition

    NASA Astrophysics Data System (ADS)

    Alfalou, A.; Brosseau, C.; Alam, M. S.

    2013-03-01

    The purpose of this paper is to test correlation methods for pattern recognition applications. A broad overview of the main correlation architectures is first given. Many correlation data are compared with those obtained from standard pattern recognition methods. We used our simulations to predict improved decisional performance from correlation methods. More specifically, we are focused on the POF filter and composite filter family. We present an optimized composite correlation filter, called asymmetric segmented phase-only filter (ASPOF) for mobile target recognition applications. The main objective is to find a compromise between the number of references to be merged in the correlation filter and the time needed for making a decision. We suggest an all-numerical implementation of a VanderLugt (VLC) type composite filter. The aim of this all-numerical implementation is to take advantage of the benefits of the correlation methods and make the correlator easily reconfigurable for various scenarios. The use of numerical implementation of the optical Fourier transform improves the decisional performance of the correlator. Further, it renders the correlator less sensitive to the saturation phenomenon caused by the increased number of references used for fabricating the composite filter. Different tests are presented making use of the peak-to-correlation energy criterion and ROC curves. These tests confirm the validity ofour technique. Elderly fall detection and underwater mine detection are two applications which are considered for illustrating the benefits of our approach. The present work is motivated by the need for detailed discussions of the choice of the correlation architecture for these specific applications, pre-processing in the input plane and post processing in the output plane techniques for such analysis.

  4. Face recognition in pictures is affected by perspective transformation but not by the centre of projection.

    PubMed

    Liu, Chang Hong; Ward, James

    2006-01-01

    Recognition of unfamiliar faces is susceptible to image differences caused by angular sizes subtended from the face to the camera. Research on perception of cubes suggests that apparent distortions of a shape due to large camera angle are correctable by placing the observer at the centre of projection, especially when visibility of the picture surface is low (Yang and Kubovy, 1999 Perception & Psychophysics 61 456-467). To explore the implication of this finding for face perception, observers performed recognition and matching tasks where face images with reduced visibility of picture surface were shown with observers either at the centre of projection or at other viewpoints. The results show that, unlike perception of cubes, the effect of perspective transformation on face recognition is largely unaffected by the centre of projection. Furthermore, the use of perspective cues is not affected by textured surfaces. The limitation of perspective in restoring 3-D information of faces suggests a stronger role for image-based, rather than model-based, processes in recognition of unfamiliar faces. PMID:17283930

  5. Developmental Changes in Face Recognition during Childhood: Evidence from Upright and Inverted Faces

    ERIC Educational Resources Information Center

    de Heering, Adelaide; Rossion, Bruno; Maurer, Daphne

    2012-01-01

    Adults are experts at recognizing faces but there is controversy about how this ability develops with age. We assessed 6- to 12-year-olds and adults using a digitized version of the Benton Face Recognition Test, a sensitive tool for assessing face perception abilities. Children's response times for correct responses did not decrease between ages 6…

  6. Effects of Repetition Priming on Recognition Memory: Testing a Perceptual Fluency-Disfluency Model

    ERIC Educational Resources Information Center

    Huber, David E.; Clark, Tedra F.; Curran, Tim; Winkielman, Piotr

    2008-01-01

    Five experiments explored the effects of immediate repetition priming on episodic recognition (the "Jacoby-Whitehouse effect") as measured with forced-choice testing. These experiments confirmed key predictions of a model adapted from D. E. Huber and R. C. O'Reilly's (2003) dynamic neural network of perception. In this model, short prime durations…

  7. The Recognition of Web Pages' Hyperlinks by People with Intellectual Disabilities: An Evaluation Study

    ERIC Educational Resources Information Center

    Rocha, Tania; Bessa, Maximino; Goncalves, Martinho; Cabral, Luciana; Godinho, Francisco; Peres, Emanuel; Reis, Manuel C.; Magalhaes, Luis; Chalmers, Alan

    2012-01-01

    Background: One of the most mentioned problems of web accessibility, as recognized in several different studies, is related to the difficulty regarding the perception of what is or is not clickable in a web page. In particular, a key problem is the recognition of hyperlinks by a specific group of people, namely those with intellectual…

  8. [Comparative studies of face recognition].

    PubMed

    Kawai, Nobuyuki

    2012-07-01

    Every human being is proficient in face recognition. However, the reason for and the manner in which humans have attained such an ability remain unknown. These questions can be best answered-through comparative studies of face recognition in non-human animals. Studies in both primates and non-primates show that not only primates, but also non-primates possess the ability to extract information from their conspecifics and from human experimenters. Neural specialization for face recognition is shared with mammals in distant taxa, suggesting that face recognition evolved earlier than the emergence of mammals. A recent study indicated that a social insect, the golden paper wasp, can distinguish their conspecific faces, whereas a closely related species, which has a less complex social lifestyle with just one queen ruling a nest of underlings, did not show strong face recognition for their conspecifics. Social complexity and the need to differentiate between one another likely led humans to evolve their face recognition abilities.

  9. Genetic specificity of face recognition.

    PubMed

    Shakeshaft, Nicholas G; Plomin, Robert

    2015-10-13

    Specific cognitive abilities in diverse domains are typically found to be highly heritable and substantially correlated with general cognitive ability (g), both phenotypically and genetically. Recent twin studies have found the ability to memorize and recognize faces to be an exception, being similarly heritable but phenotypically substantially uncorrelated both with g and with general object recognition. However, the genetic relationships between face recognition and other abilities (the extent to which they share a common genetic etiology) cannot be determined from phenotypic associations. In this, to our knowledge, first study of the genetic associations between face recognition and other domains, 2,000 18- and 19-year-old United Kingdom twins completed tests assessing their face recognition, object recognition, and general cognitive abilities. Results confirmed the substantial heritability of face recognition (61%), and multivariate genetic analyses found that most of this genetic influence is unique and not shared with other cognitive abilities.

  10. Retina vascular network recognition

    NASA Astrophysics Data System (ADS)

    Tascini, Guido; Passerini, Giorgio; Puliti, Paolo; Zingaretti, Primo

    1993-09-01

    The analysis of morphological and structural modifications of the retina vascular network is an interesting investigation method in the study of diabetes and hypertension. Normally this analysis is carried out by qualitative evaluations, according to standardized criteria, though medical research attaches great importance to quantitative analysis of vessel color, shape and dimensions. The paper describes a system which automatically segments and recognizes the ocular fundus circulation and micro circulation network, and extracts a set of features related to morphometric aspects of vessels. For this class of images the classical segmentation methods seem weak. We propose a computer vision system in which segmentation and recognition phases are strictly connected. The system is hierarchically organized in four modules. Firstly the Image Enhancement Module (IEM) operates a set of custom image enhancements to remove blur and to prepare data for subsequent segmentation and recognition processes. Secondly the Papilla Border Analysis Module (PBAM) automatically recognizes number, position and local diameter of blood vessels departing from optical papilla. Then the Vessel Tracking Module (VTM) analyses vessels comparing the results of body and edge tracking and detects branches and crossings. Finally the Feature Extraction Module evaluates PBAM and VTM output data and extracts some numerical indexes. Used algorithms appear to be robust and have been successfully tested on various ocular fundus images.

  11. Complex Event Recognition Architecture

    NASA Technical Reports Server (NTRS)

    Fitzgerald, William A.; Firby, R. James

    2009-01-01

    Complex Event Recognition Architecture (CERA) is the name of a computational architecture, and software that implements the architecture, for recognizing complex event patterns that may be spread across multiple streams of input data. One of the main components of CERA is an intuitive event pattern language that simplifies what would otherwise be the complex, difficult tasks of creating logical descriptions of combinations of temporal events and defining rules for combining information from different sources over time. In this language, recognition patterns are defined in simple, declarative statements that combine point events from given input streams with those from other streams, using conjunction, disjunction, and negation. Patterns can be built on one another recursively to describe very rich, temporally extended combinations of events. Thereafter, a run-time matching algorithm in CERA efficiently matches these patterns against input data and signals when patterns are recognized. CERA can be used to monitor complex systems and to signal operators or initiate corrective actions when anomalous conditions are recognized. CERA can be run as a stand-alone monitoring system, or it can be integrated into a larger system to automatically trigger responses to changing environments or problematic situations.

  12. Sudden Event Recognition: A Survey

    PubMed Central

    Suriani, Nor Surayahani; Hussain, Aini; Zulkifley, Mohd Asyraf

    2013-01-01

    Event recognition is one of the most active research areas in video surveillance fields. Advancement in event recognition systems mainly aims to provide convenience, safety and an efficient lifestyle for humanity. A precise, accurate and robust approach is necessary to enable event recognition systems to respond to sudden changes in various uncontrolled environments, such as the case of an emergency, physical threat and a fire or bomb alert. The performance of sudden event recognition systems depends heavily on the accuracy of low level processing, like detection, recognition, tracking and machine learning algorithms. This survey aims to detect and characterize a sudden event, which is a subset of an abnormal event in several video surveillance applications. This paper discusses the following in detail: (1) the importance of a sudden event over a general anomalous event; (2) frameworks used in sudden event recognition; (3) the requirements and comparative studies of a sudden event recognition system and (4) various decision-making approaches for sudden event recognition. The advantages and drawbacks of using 3D images from multiple cameras for real-time application are also discussed. The paper concludes with suggestions for future research directions in sudden event recognition. PMID:23921828

  13. Frequency-Based Fingerprint Recognition

    NASA Astrophysics Data System (ADS)

    Aguilar, Gualberto; Sánchez, Gabriel; Toscano, Karina; Pérez, Héctor

    abstract Fingerprint recognition is one of the most popular methods used for identification with greater success degree. Fingerprint has unique characteristics called minutiae, which are points where a curve track ends, intersects, or branches off. In this chapter a fingerprint recognition method is proposed in which a combination of Fast Fourier Transform (FFT) and Gabor filters is used for image enhancement. A novel recognition stage using local features for recognition is also proposed. Also a verification stage is introduced to be used when the system output has more than one person.

  14. Influence of fresh alfalfa supplementation on fat skatole and indole concentration and chop odour and flavour in lambs grazing a cocksfoot pasture.

    PubMed

    Devincenzi, T; Prunier, A; Meteau, K; Nabinger, C; Prache, S

    2014-12-01

    We investigated the influence of the level of fresh alfalfa supplementation on fat skatole and indole concentration and chop sensory attributes in grazing lambs. Four groups of nine male Romane lambs grazing a cocksfoot pasture were supplemented with various levels of alfalfa for at least 60days before slaughter. Perirenal fat skatole concentration was higher for lambs that consumed alfalfa than for those that consumed only cocksfoot. The intensity of 'animal' odour in the lean part of the chop and of 'animal' flavour in both the lean and fat parts of the chop, evaluated by a trained sensory panel, increased from the lowest level of alfalfa supplementation onwards and did not increase further with increasing levels of alfalfa supplementation. The outcome of this study therefore suggests that these sensory attributes may reach a plateau when perirenal fat skatole concentration is in the range 0.16-0.24μg/g of liquid fat. PMID:25089784

  15. The MC4R c.893G>A mutation: a marker for growth and leanness associated with boar taint odour in Belgian pig breeds.

    PubMed

    Schroyen, M; Janssens, S; Stinckens, A; Brebels, M; Bertolini, F; Lamberigts, C; Bekaert, K; Vanhaecke, L; Aluwé, M; Tuyttens, F A M; Millet, S; Buys, N

    2015-03-01

    Since surgical castration of male piglets without anaesthesia is under heavy societal pressure, finding a sustainable solution to reduce boar taint has become urgent. One way to circumvent this animal welfare violation is raising entire male pigs whilst selecting against the tainted phenotype through marker-assisted selection. Since slaughtering at a lower weight is often suggested to reduce boar taint, selection using a marker for that trait could be a promising strategy. Therefore, in this study a melanocortin 4 receptor (MC4R) mutation, frequently described in different pig breeds as marker for fat content, weight gain and feed intake, was examined in relation to boar taint in pig breeds used in Belgian pig farms. Although results suggest an association between this mutation and a boar taint odour score assigned by experts, no association was found between the mutation and the concentration of the individual chemical boar taint components androstenone, skatole and indole. PMID:25462375

  16. Response of male mice to odours of female mice in different stages of oestrous cycle: self-grooming behaviour and the effect of castration.

    PubMed

    Achiraman, Shanmugam; SankarGanesh, Devaraj; Kannan, Soundarapandian; Kamalakkannan, Soundararajan; Nirmala, Natarajan; Archunan, Govindaraju

    2014-01-01

    The behavioural assays were carried out in a Y-maze wherein intact, castrated and testosterone-treated male mice were exposed to oestrus and non-oestrus urine samples. The intact male mice investigated more frequently and spent more time in the Y-maze arm with oestrus urine than in that with non-oestrus urine. In contrast, the castrated mice were not attracted to oestrus urine, whereas testosterone-treated mice showed preference for oestrus urine. The rate of self-grooming was higher in intact males in case of exposure to oestrus urine while the rate was lower with respect to non-oestrus urine. However, castrated mice exhibited less self-grooming behaviour which was partially restored by testosterone treatment. The results suggest that self-grooming behaviour is an indicator of detection and discrimination of oestrus by males, and supports the androgen role in male chemosensory ability to discriminate between oestrus and non-oestrus female odours.

  17. H2S, VOC, TOC, electronic noses and odour concentration: use and comparison of different parameters for emission measurement on air treatment systems.

    PubMed

    Franke, W; Frechen, F-B; Giebel, S

    2009-01-01

    Odour measurement via olfactometry is expensive and has a low accuracy compared with chemical or physical methods. In addition, olfactometry is not suited for online monitoring. Hence, an accurate online method for emission measurement would be an enormous improvement. There are several options to more or less replace the offline olfactometry by online measurement available today. Most common are H2S-concentration as a single gas parameter and VOC and TOC as composite parameters. A fairly new development are multi sensor arrays, usually referred to as "electronic noses" which carry out non-specific gas measurement and deliver measurement data that can visualized as a fingerprint diagram. This paper outlines the use of these different parameters and compares the results to those gained via olfactometry of several case studies.

  18. Perceptual biases in facial emotion recognition in borderline personality disorder.

    PubMed

    Daros, Alexander R; Uliaszek, Amanda A; Ruocco, Anthony C

    2014-01-01

    Individuals with borderline personality disorder (BPD) have biases in facial emotion recognition, which may underlie many of the core features of this disorder. Although they are known to misperceive specific prototypic expressions of emotion (i.e., those displayed at full emotional intensity), patients with this disorder may also show biases in their perceptions of emotions that are expressed at lower levels of emotional intensity. Females with BPD (n = 31) and IQ- and demographically matched nonpsychiatric controls (n = 28) completed a task assessing the recognition of neutral as well as happy and sad facial expressions at mild, moderate, and prototypic emotional intensities. Whereas patients with BPD were more likely than controls to ascribe an emotion to a neutral facial expression, they did not consistently attribute a more negative or positive valence to these faces as compared with controls. Patients were also more likely to perceive mildly sad facial expressions as more intensely sad, and this finding could not be attributed to depressed mood. The results of this study suggest that perceptions of even subtle expressions of negative affect in faces may be subjectively magnified by individuals with BPD, although there was no consistent evidence for a negative perceptual bias for faces displaying a neutral expression. These biases in facial emotion perception for patients with BPD may contribute to difficulties understanding others' emotional states and to problems engaging effectively in social interactions.

  19. Hazard recognition in mining: A psychological perspective. Information circular/1995

    SciTech Connect

    Perdue, C.W.; Kowalski, K.M.; Barrett, E.A.

    1995-07-01

    This U.S. Bureau of Mines report considers, from a psychological perspective, the perceptual process by which miners recognize and respond to mining hazards. It proposes that if the hazard recognition skills of miners can be improved, mining accidents may be reduced to a significant degree. Prior studies of hazard perception in mining are considered, as are relevant studies from investigations of military target identification, pilot and gunnery officer training, transportation safety, automobile operator behavior, as well as research into sensory functioning and visual information processing. A general model of hazard perception is introduced, and selected concepts from the psychology of perception that are applicable to the detection of mining hazards are reviewed. Hazard recognition is discussed as a function of the perceptual cues available to the miner as well as the cognitive resources and strategies employed by the miner. The development of expertise in resonding to hazards is related to individual differences in the experience, aptitude, and personality of the worker. Potential applications to miner safety and training are presented.

  20. Use of intonation contours for speech recognition in noise by cochlear implant recipients.

    PubMed

    Meister, Hartmut; Landwehr, Markus; Pyschny, Verena; Grugel, Linda; Walger, Martin

    2011-05-01

    The corruption of intonation contours has detrimental effects on sentence-based speech recognition in normal-hearing listeners Binns and Culling [(2007). J. Acoust. Soc. Am. 122, 1765-1776]. This paper examines whether this finding also applies to cochlear implant (CI) recipients. The subjects' F0-discrimination and speech perception in the presence of noise were measured, using sentences with regular and inverted F0-contours. The results revealed that speech recognition for regular contours was significantly better than for inverted contours. This difference was related to the subjects' F0-discrimination providing further evidence that the perception of intonation patterns is important for the CI-mediated speech recognition in noise.