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Sample records for odor separating system

  1. An artificial odor recognition system is developed for discriminating odors

    Directory of Open Access Journals (Sweden)

    Wisnu Jatmiko

    2002-12-01

    Full Text Available This artificial system consisted of 16 quartz resonator crystals as the sensor array, a frequency modulator and a frequency counter for each sensor that are connected directly to a microcomputer. We have already shown that the artificial odor recognition system with 4 sensors is high enough to discriminate simple odor correctly, however, when it was used to discriminate compound odors, the recognition capability of this system is dropped significantly to be about 40%. Results of experiments show that the developed artificial system with 16 sensors could discriminate compound aroma based on 6 gradient of alcohol concentrations with high recognition rate of 89.9% for non batch processing system, and 82.4% for batch processing of the classes of odors.

  2. Unexpected plant odor responses in a moth pheromone system

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    Angéla eRouyar

    2015-05-01

    Full Text Available Male moths rely on olfactory cues to find females for reproduction. Males also use volatile plant compounds (VPCs to find food sources and might use host-plant odor cues to identify the habitat of calling females. Both the sex pheromone released by conspecific females and VPCs trigger well-described oriented flight behavior towards the odor source. Whereas detection and central processing of pheromones and VPCs have been thought for a long time to be highly separated from each other, recent studies have shown that interactions of both types of odors occur already early at the periphery of the olfactory pathway. Here we show that detection and early processing of VPCs and pheromone can overlap between the two sub-systems. Using complementary approaches, i.e. single-sensillum recording of olfactory receptor neurons, in vivo calcium imaging in the antennal lobe, intracellular recordings of neurons in the macroglomerular complex (MGC and flight tracking in a wind tunnel, we show that some plant odorants alone, such as heptanal, activate the pheromone-specific pathway in male Agrotis ipsilon at peripheral and central levels. To our knowledge, this is the first report of a plant odorant with no chemical similarity to the molecular structure of the pheromone, acting as a partial agonist of a moth sex pheromone.

  3. Functional neuronal processing of body odors differs from that of similar common odors.

    Science.gov (United States)

    Lundström, Johan N; Boyle, Julie A; Zatorre, Robert J; Jones-Gotman, Marilyn

    2008-06-01

    Visual and auditory stimuli of high social and ecological importance are processed in the brain by specialized neuronal networks. To date, this has not been demonstrated for olfactory stimuli. By means of positron emission tomography, we sought to elucidate the neuronal substrates behind body odor perception to answer the question of whether the central processing of body odors differs from perceptually similar nonbody odors. Body odors were processed by a network that was distinctly separate from common odors, indicating a separation in the processing of odors based on their source. Smelling a friend's body odor activated regions previously seen for familiar stimuli, whereas smelling a stranger activated amygdala and insular regions akin to what has previously been demonstrated for fearful stimuli. The results provide evidence that social olfactory stimuli of high ecological relevance are processed by specialized neuronal networks similar to what has previously been demonstrated for auditory and visual stimuli.

  4. Olfactory systems and neural circuits that modulate predator odor fear

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    Lorey K. Takahashi

    2014-03-01

    Full Text Available When prey animals detect the odor of a predator a constellation of fear-related autonomic, endocrine, and behavioral responses rapidly occur to facilitate survival. How olfactory sensory systems process predator odor and channel that information to specific brain circuits is a fundamental issue that is not clearly understood. However, research in the last 15 years has begun to identify some of the essential features of the sensory detection systems and brain structures that underlie predator odor fear. For instance, the main (MOS and accessory olfactory systems (AOS detect predator odors and different types of predator odors are sensed by specific receptors located in either the MOS or AOS. However, complex predator chemosignals may be processed by both the MOS and AOS, which complicate our understanding of the specific neural circuits connected directly and indirectly from the MOS and AOS to activate the physiological and behavioral components of unconditioned and conditioned fear. Studies indicate that brain structures including the dorsal periaqueductal gray, paraventricular nucleus of the hypothalamus, and the medial amygdala appear to be broadly involved in predator odor induced autonomic activity and hypothalamic-pituitary-adrenal stress hormone secretion. The medial amygdala also plays a key role in predator odor unconditioned fear behavior and retrieval of contextual fear memory associated with prior predator odor experiences. Other neural structures including the bed nucleus of the stria terminalis and the ventral hippocampus appear prominently involve in predator odor fear behavior. The basolateral amygdala, medial hypothalamic nuclei, and medial prefrontal cortex are also activated by some but not all predator odors. Future research that characterizes how distinct predator odors are uniquely processed in olfactory systems and neural circuits will provide significant insights into the differences of how diverse predator odors activate

  5. Olfactory systems and neural circuits that modulate predator odor fear

    Science.gov (United States)

    Takahashi, Lorey K.

    2014-01-01

    When prey animals detect the odor of a predator a constellation of fear-related autonomic, endocrine, and behavioral responses rapidly occur to facilitate survival. How olfactory sensory systems process predator odor and channel that information to specific brain circuits is a fundamental issue that is not clearly understood. However, research in the last 15 years has begun to identify some of the essential features of the sensory detection systems and brain structures that underlie predator odor fear. For instance, the main (MOS) and accessory olfactory systems (AOS) detect predator odors and different types of predator odors are sensed by specific receptors located in either the MOS or AOS. However, complex predator chemosignals may be processed by both the MOS and AOS, which complicate our understanding of the specific neural circuits connected directly and indirectly from the MOS and AOS to activate the physiological and behavioral components of unconditioned and conditioned fear. Studies indicate that brain structures including the dorsal periaqueductal gray (DPAG), paraventricular nucleus (PVN) of the hypothalamus, and the medial amygdala (MeA) appear to be broadly involved in predator odor induced autonomic activity and hypothalamic-pituitary-adrenal (HPA) stress hormone secretion. The MeA also plays a key role in predator odor unconditioned fear behavior and retrieval of contextual fear memory associated with prior predator odor experiences. Other neural structures including the bed nucleus of the stria terminalis and the ventral hippocampus (VHC) appear prominently involved in predator odor fear behavior. The basolateral amygdala (BLA), medial hypothalamic nuclei, and medial prefrontal cortex (mPFC) are also activated by some but not all predator odors. Future research that characterizes how distinct predator odors are uniquely processed in olfactory systems and neural circuits will provide significant insights into the differences of how diverse predator

  6. Order of exposure to pleasant and unpleasant odors affects autonomic nervous system response.

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    Horii, Yuko; Nagai, Katsuya; Nakashima, Toshihiro

    2013-04-15

    When mammals are exposed to an odor, that odor is expected to elicit a physiological response in the autonomic nervous system. An unpleasant aversive odor causes non-invasive stress, while a pleasant odor promotes healing and relaxation in mammals. We hypothesized that pleasant odors might reduce a stress response previously induced by an aversive predator odor. Rats were thus exposed to pleasant and unpleasant odors in different orders to determine whether the order of odor exposure had an effect on the physiological response in the autonomic nervous system. The first trial examined autonomic nerve activity via sympathetic and parasympathetic nerve response while the second trial examined body temperature response. Initial exposure to a pleasant odor elicited a positive response and secondary exposure to an unpleasant odor elicited a negative response, as expected. However, we found that while initial exposure to an unpleasant odor elicited a negative stress response, subsequent secondary exposure to a pleasant odor not only did not alleviate that negative response, but actually amplified it. These findings were consistent for both the autonomic nerve activity response trial and the body temperature response trial. The trial results suggest that exposure to specific odors does not necessarily result in the expected physiological response and that the specific order of exposure plays an important role. Our study should provide new insights into our understanding of the physiological response in the autonomic nervous system related to odor memory and discrimination and point to areas that require further research. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Odor composition analysis and odor indicator selection during sewage sludge composting

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    Zhu, Yan-li; Zheng, Guo-di; Gao, Ding; Chen, Tong-bin; Wu, Fang-kun; Niu, Ming-jie; Zou, Ke-hua

    2016-01-01

    ABSTRACT On the basis of total temperature increase, normal dehydration, and maturity, the odor compositions of surface and internal piles in a well-run sewage sludge compost plant were analyzed using gas chromatography–mass spectrometry with a liquid nitrogen cooling system and a portable odor detector. Approximately 80 types of substances were detected, including 2 volatile inorganic compounds, 4 sulfur organic compounds, 16 benzenes, 27 alkanes, 15 alkenes, and 19 halogenated compounds. Most pollutants were mainly produced in the mesophilic and pre-thermophilic periods. The sulfur volatile organic compounds contributed significantly to odor and should be controlled primarily. Treatment strategies should be based on the properties of sulfur organic compounds. Hydrogen sulfide, methyl mercaptan, dimethyl disulfide, dimethyl sulfide, ammonia, and carbon disulfide were selected as core indicators. Ammonia, hydrogen sulfide, carbon disulfide, dimethyl disulfide, methyl mercaptan, dimethylbenzene, phenylpropane, and isopentane were designated as concentration indicators. Benzene, m-xylene, p-xylene, dimethylbenzene, dichloromethane, toluene, chlorobenzene, trichloromethane, carbon tetrachloride, and ethylbenzene were selected as health indicators. According to the principle of odor pollution indicator selection, dimethyl disulfide was selected as an odor pollution indicator of sewage sludge composting. Monitoring dimethyl disulfide provides a highly scientific method for modeling and evaluating odor pollution from sewage sludge composting facilities. Implications: Composting is one of the most important methods for sewage sludge treatment and improving the low organic matter content of many agricultural soils. However, odors are inevitably produced during the composting process. Understanding the production and emission patterns of odors is important for odor control and treatment. Core indicators, concentration indicators, and health indicators provide an index

  8. Odor composition analysis and odor indicator selection during sewage sludge composting.

    Science.gov (United States)

    Zhu, Yan-Li; Zheng, Guo-di; Gao, Ding; Chen, Tong-Bin; Wu, Fang-Kun; Niu, Ming-Jie; Zou, Ke-Hua

    2016-09-01

    On the basis of total temperature increase, normal dehydration, and maturity, the odor compositions of surface and internal piles in a well-run sewage sludge compost plant were analyzed using gas chromatography-mass spectrometry with a liquid nitrogen cooling system and a portable odor detector. Approximately 80 types of substances were detected, including 2 volatile inorganic compounds, 4 sulfur organic compounds, 16 benzenes, 27 alkanes, 15 alkenes, and 19 halogenated compounds. Most pollutants were mainly produced in the mesophilic and pre-thermophilic periods. The sulfur volatile organic compounds contributed significantly to odor and should be controlled primarily. Treatment strategies should be based on the properties of sulfur organic compounds. Hydrogen sulfide, methyl mercaptan, dimethyl disulfide, dimethyl sulfide, ammonia, and carbon disulfide were selected as core indicators. Ammonia, hydrogen sulfide, carbon disulfide, dimethyl disulfide, methyl mercaptan, dimethylbenzene, phenylpropane, and isopentane were designated as concentration indicators. Benzene, m-xylene, p-xylene, dimethylbenzene, dichloromethane, toluene, chlorobenzene, trichloromethane, carbon tetrachloride, and ethylbenzene were selected as health indicators. According to the principle of odor pollution indicator selection, dimethyl disulfide was selected as an odor pollution indicator of sewage sludge composting. Monitoring dimethyl disulfide provides a highly scientific method for modeling and evaluating odor pollution from sewage sludge composting facilities. Composting is one of the most important methods for sewage sludge treatment and improving the low organic matter content of many agricultural soils. However, odors are inevitably produced during the composting process. Understanding the production and emission patterns of odors is important for odor control and treatment. Core indicators, concentration indicators, and health indicators provide an index system to odor evaluation

  9. Olfactory systems and neural circuits that modulate predator odor fear

    OpenAIRE

    Takahashi, Lorey K.

    2014-01-01

    When prey animals detect the odor of a predator a constellation of fear-related autonomic, endocrine, and behavioral responses rapidly occur to facilitate survival. How olfactory sensory systems process predator odor and channel that information to specific brain circuits is a fundamental issue that is not clearly understood. However, research in the last 15 years has begun to identify some of the essential features of the sensory detection systems and brain structures that underlie predator ...

  10. Odorants for surveillance and control of the Asian Citrus Psyllid (Diaphorina citri.

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    Iliano V Coutinho-Abreu

    Full Text Available The Asian Citrus Psyllid (ACP, Diaphorina citri, can transmit the bacterium Candidatus Liberibacter while feeding on citrus flush shoots. This bacterium causes Huanglongbing (HLB, a major disease of citrus cultivation worldwide necessitating the development of new tools for ACP surveillance and control. The olfactory system of ACP is sensitive to variety of odorants released by citrus plants and offers an opportunity to develop new attractants and repellents.In this study, we performed single-unit electrophysiology to identify odorants that are strong activators, inhibitors, and prolonged activators of ACP odorant receptor neurons (ORNs. We identified a suite of odorants that activated the ORNs with high specificity and sensitivity, which may be useful in eliciting behavior such as attraction. In separate experiments, we also identified odorants that evoked prolonged ORN responses and antagonistic odorants able to suppress neuronal responses to activators, both of which can be useful in lowering attraction to hosts. In field trials, we tested the electrophysiologically identified activating odorants and identified a 3-odor blend that enhances trap catches by ∼230%.These findings provide a set of odorants that can be used to develop affordable and safe odor-based surveillance and masking strategies for this dangerous pest insect.

  11. Coincidence of pheromone and plant odor leads to sensory plasticity in the heliothine olfactory system.

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    Elena Ian

    Full Text Available Male moths possess a highly specialized olfactory system comprised of two segregated sub-arrangements dedicated to processing information about plant odors and pheromones, respectively. Communication between these two sub-systems has been described at the peripheral level, but relatively little is known about putative interactions at subsequent synaptic relays. The male moth faces the challenge of seeking out the conspecific female in a highly dynamic odor world. The female-produced pheromone blend, which is a limited resource serving as guidance for the male, will reach his antennae in intermittent pockets of odor filaments mixed with volatiles from various plants. In the present study we performed calcium imaging for measuring odor-evoked responses in the uni-glomerular antennal-lobe projection neurons (analog to mitral cells in the vertebrate olfactory bulb of Helicoverpa armigera. In order to investigate putative interactions between the two sub-systems tuned to plant volatiles and pheromones, respectively, we performed repeated stimulations with a selection of biologically relevant odors. We found that paired stimulation with a plant odor and the pheromone led to suppressed responses in both sub-systems as compared to those evoked during initial stimulation including application of each odor stimulus alone. The fact that the suppression persisted also after pairing, indicates the existence of a Hebbian-like plasticity in the primary olfactory center established by temporal pairing of the two odor stimulation categories.

  12. Assessment and remediation of odor emissions from a complex industrial facility (Ambient air odor regulations in Canada and the United States)

    International Nuclear Information System (INIS)

    Boose, T.; Reusing, G.

    2002-01-01

    This paper describes the findings of a review and presents examples of ambient air odor regulations in Canada and the United States. State and provincial odor regulations were reviewed and other metropolitan cities or counties (regions) that have separate odor regulations were also included. The key topics addressed in this paper include an assessment of the methods used for odor regulation and the methods used to evaluate the odor impact to determine compliance with the regulation. Three types of ambient air odor regulations were identified: 1. 28 States, Provinces and regions (jurisdictions) have specific odor regulations. These regulations generally define what constitutes an odor impact and typically provide requirements for remedial measures; 2. 25 jurisdictions regulate odors by a general prohibition regulation. These regulations define odor in ambient air as a condition of air pollution, nuisance or objectionable odor that would typically prevent persons from the enjoyment of life and property; and 3. 13 jurisdictions do not have specific or general prohibition regulations regarding odors. For the jurisdictions that have specific or general prohibition odor regulations, there are a number of different techniques used to define what constitutes an odor impact. Odor impacts are typically defined in a regulation by one (or more) of the following techniques: dilution to threshold, or odor unit limit; determination of odor emission rates; odor concentration limits for selected chemicals (ppm); comparison with the n-butanol intensity scale (1 to 8); and investigation by an agency investigator. Compliance with odor regulations is typically determined using one (or more) of the following field methods: odor stack testing and dispersion modelling; odor panel analysis of stack or ambient air samples; chemical monitoring (ppm); odor school certified / agency investigator; and scentometer. (author)

  13. Body position-dependent shift in odor percept present only for perithreshold odors.

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    Lundström, Johan N; Boyle, Julie A; Jones-Gotman, Marilyn

    2008-01-01

    We recently demonstrated that a supine position causes a decrease in olfactory sensitivity compared with an upright position. We pursued that initial finding in 3 separate experiments in which we explored the extent of, and mechanism underlying, this phenomenon. In Experiment 1, we replicated the decrease in olfactory sensitivity when in a supine compared with an upright position. In Experiment 2, we measured body position-dependent shifts in physiological variables and sniff measures while smelling suprathreshold odorants and performing a perithreshold odor intensity discrimination task. Olfactory performances were reduced while supine. However, no relationships between the shift in olfactory performances and either the physiological variables or sniff measures were found. In Experiment 3, we determined that there were no position-dependent shifts in ability to discriminate or identify suprathreshold odors or rate them for pleasantness, intensity, or familiarity. However, a drop in scores was observed, and performance was slowed, on a cognitive skill while supine. These results demonstrate a body position-dependent shift in olfactory sensitivity only for perithreshold odors that appears to be mediated by cognitive rather than physiological factors. Implications for olfactory imaging studies are discussed.

  14. Odors cue memory for odor-associated words

    OpenAIRE

    Stafford, Lorenzo; Salehi, S.; Waller, Bridget

    2009-01-01

    The ability of odors to cue vivid and emotionally intense memories is well-known. However, the majority of research has focused on the extent to which odors can act as environmental cues to memory, where odors are presented alongside the stimuli to be remembered, rather than the extent to which pre-existing associations between odor and odor-related stimuli might influence memory. In this study, participants (n = 45 females in each experiment) were presented with words (two groups of odor-ass...

  15. Evaluation method of offensive odor. Shuki no hyoka hoho

    Energy Technology Data Exchange (ETDEWEB)

    Iwasaki, Y [The Tokyo Metropolitan Research Institute for Environmental Protection, Tokyo (Japan)

    1991-06-01

    As the evaluation method of offensive odor, two kinds of methods were outlined, a concentration measurement method for compounds emitting offensive odors and a sensory method by human olfactory organ. On the former, the method for measuring separately odors of twelve compounds controlled by the regulation act such as ammonia and hydrogen sulfide was outlined as well as the method for measuring odors of compound groups such as total reduced sulfur and total hydrocarbon. On the later, the evaluation scale of essential properties of odor such as quality, intensity, acceptability and pervasiveness was discussed. As typical sensory techniques, a scentometer, syringe method, odorless chamber method and olfactometer were outlined, and a triangle odor bag method widely used for the evaluation at present was described in detail which was developed to reduce demerits of a syringe method such as adsorption of odorants on a syringe surface. 24 refs., 6 figs., 3 tabs.

  16. An odor interaction model of binary odorant mixtures by a partial differential equation method.

    Science.gov (United States)

    Yan, Luchun; Liu, Jiemin; Wang, Guihua; Wu, Chuandong

    2014-07-09

    A novel odor interaction model was proposed for binary mixtures of benzene and substituted benzenes by a partial differential equation (PDE) method. Based on the measurement method (tangent-intercept method) of partial molar volume, original parameters of corresponding formulas were reasonably displaced by perceptual measures. By these substitutions, it was possible to relate a mixture's odor intensity to the individual odorant's relative odor activity value (OAV). Several binary mixtures of benzene and substituted benzenes were respectively tested to establish the PDE models. The obtained results showed that the PDE model provided an easily interpretable method relating individual components to their joint odor intensity. Besides, both predictive performance and feasibility of the PDE model were proved well through a series of odor intensity matching tests. If combining the PDE model with portable gas detectors or on-line monitoring systems, olfactory evaluation of odor intensity will be achieved by instruments instead of odor assessors. Many disadvantages (e.g., expense on a fixed number of odor assessors) also will be successfully avoided. Thus, the PDE model is predicted to be helpful to the monitoring and management of odor pollutions.

  17. Preliminary analysis of odor legal solutions and study on their implementation possibilities in Poland

    Science.gov (United States)

    Sówka, Izabela; Karski, Leszek

    2018-01-01

    The problem of odor nuisance requires undertaking legal means that aim towards implementation of regulations in order to improve the odor-related quality of air in selected areas in Poland. So far the works carried out in the country were concluded by drawing up `The guidelines for the bill on counteracting the odor nuisance'. However, as a result of completed social consultations in Poland, the Ministry of Environment, in 2015, resigned from implementing of so called anti-odor act. Currently, the legislature is taking steps which aim at undertaking specific actions in order to introduce solutions, which would directly regulate the issues of odors and the odor nuisance, to the national system. In the countries of the European Union, the issues related to odors are solved in diversified ways and the system still lacks of a uniform proposition, among others related to odor standards. In connection with the above, actions that are taken on a national level should fundamentally aim at developing national odor standards which would take into account the type / the kind of economic activity being a source of odor emission (e.g. clearly separated for existing objects and planned investments), at establishing a procedure and also legal and operational requirements related to determination and the types of zones with defined values of acceptable concentration and determination of reference methodology in monitoring, and modeling the dispersion of odors e.g. including strictly defined frequency of necessary tests. In addition, the process should be accompanied by a creation of financial mechanisms and streams in range of investments related to the development of technology and methods used to limit emission of odors.

  18. Central insulin administration improves odor-cued reactivation of spatial memory in young men.

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    Brünner, Yvonne F; Kofoet, Anja; Benedict, Christian; Freiherr, Jessica

    2015-01-01

    Insulin receptors are ubiquitously found in the human brain, comprising the olfactory bulb, essential for odor processing, and the hippocampus, important for spatial memory processing. The present study aimed at examining if intranasal insulin, which is known to transiently increase brain insulin levels in humans, would improve odor-cued reactivation of spatial memory in young men. We applied a double-blind, placebo-controlled, counterbalanced within-subject design. The study was conducted at the research unit of a university hospital. Interventions/Participants/Main Outcome Measures: Following intranasal administration of either insulin (40 I.U.) or placebo, male subjects (n = 18) were exposed to eight odors. During each odor exposure, a green-colored field was presented on a 17-in. computer screen. During immediate recall (comprising 3 runs), the participants were re-exposed to each odor cue, and were asked to select the corresponding field (with visual feedback after each response). The delayed recall was scheduled ∼10 min later (without feedback). To test if insulin's putative effect on odor-place memory would be domain-specific, participants also performed a separate place and odor recognition task. Intranasal insulin improved the delayed but not immediate odor-cued recall of spatial memory. This effect was independent of odor type and in the absence of systemic side effects (eg, fasting plasma glucose levels remained unaltered). Place and odor recognition were unaffected by the insulin treatment. These findings suggest that acute intranasal insulin improves odor-cued reactivation of spatial memory in young men.

  19. An Odor Interaction Model of Binary Odorant Mixtures by a Partial Differential Equation Method

    Directory of Open Access Journals (Sweden)

    Luchun Yan

    2014-07-01

    Full Text Available A novel odor interaction model was proposed for binary mixtures of benzene and substituted benzenes by a partial differential equation (PDE method. Based on the measurement method (tangent-intercept method of partial molar volume, original parameters of corresponding formulas were reasonably displaced by perceptual measures. By these substitutions, it was possible to relate a mixture’s odor intensity to the individual odorant’s relative odor activity value (OAV. Several binary mixtures of benzene and substituted benzenes were respectively tested to establish the PDE models. The obtained results showed that the PDE model provided an easily interpretable method relating individual components to their joint odor intensity. Besides, both predictive performance and feasibility of the PDE model were proved well through a series of odor intensity matching tests. If combining the PDE model with portable gas detectors or on-line monitoring systems, olfactory evaluation of odor intensity will be achieved by instruments instead of odor assessors. Many disadvantages (e.g., expense on a fixed number of odor assessors also will be successfully avoided. Thus, the PDE model is predicted to be helpful to the monitoring and management of odor pollutions.

  20. Preservation of Essential Odor-Guided Behaviors and Odor-Based Reversal Learning after Targeting Adult Brain Serotonin Synthesis.

    Science.gov (United States)

    Carlson, Kaitlin S; Whitney, Meredith S; Gadziola, Marie A; Deneris, Evan S; Wesson, Daniel W

    2016-01-01

    The neurotransmitter serotonin (5-HT) is considered a powerful modulator of sensory system organization and function in a wide range of animals. The olfactory system is innervated by midbrain 5-HT neurons into both its primary and secondary odor-processing stages. Facilitated by this circuitry, 5-HT and its receptors modulate olfactory system function, including odor information input to the olfactory bulb. It is unknown, however, whether the olfactory system requires 5-HT for even its most basic behavioral functions. To address this question, we established a conditional genetic approach to specifically target adult brain tryptophan hydroxylase 2 ( Tph2 ), encoding the rate-limiting enzyme in brain 5-HT synthesis, and nearly eliminate 5-HT from the mouse forebrain. Using this novel model, we investigated the behavior of 5-HT-depleted mice during performance in an olfactory go/no-go task. Surprisingly, the near elimination of 5-HT from the forebrain, including the olfactory bulbs, had no detectable effect on the ability of mice to perform the odor-based task. Tph2 -targeted mice not only were able to learn the task, but also had levels of odor acuity similar to those of control mice when performing coarse odor discrimination. Both groups of mice spent similar amounts of time sampling odors during decision-making. Furthermore, odor reversal learning was identical between 5-HT-depleted and control mice. These results suggest that 5-HT neurotransmission is not necessary for the most essential aspects of olfaction, including odor learning, discrimination, and certain forms of cognitive flexibility.

  1. Odor Emotional Quality Predicts Odor Identification.

    Science.gov (United States)

    Bestgen, Anne-Kathrin; Schulze, Patrick; Kuchinke, Lars

    2015-09-01

    It is commonly agreed upon a strong link between emotion and olfaction. Odor-evoked memories are experienced as more emotional compared with verbal, visual, and tactile stimuli. Moreover, the emotional quality of odor cues increases memory performance, but contrary to this, odors are poor retrieval cues for verbal labels. To examine the relation between the emotional quality of an odor and its likelihood of identification, this study evaluates how normative emotion ratings based on the 3-dimensional affective space model (that includes valence, arousal, and dominance), using the Self-Assessment Manikin by Bradley and Lang (Bradley MM, Lang PJ. 1994. Measuring emotion: the Self-Assessment Manikin and the Semantic Differential. J Behav Ther Exp Psychiatry. 25(1):49-59.) and the Positive and Negative Affect Schedule (Watson D, Clark LA, Tellegen A. 1988. Development and validation of brief measures of positive and negative affect: the PANAS scales. J Pers Soc Psychol. 54(6):1063-1070.) predict the identification of odors in a multiple choice condition. The best fitting logistic regression model includes squared valence and dominance and thus, points to a significant role of specific emotional features of odors as a main clue for odor identification. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. The Accessory Olfactory System Facilitates the Recovery of the Attraction to Familiar Volatile Female Odors in Male Mice.

    Science.gov (United States)

    Muroi, Yoshikage; Nishimura, Masakazu; Ishii, Toshiaki

    2017-10-31

    Odors in female mice induce sexual arousal in male mice. Repeated exposure to female odors attenuates male attraction, which recovers when the odors are removed. The neuronal mechanisms for the recovery of male attraction have not been clarified. In this study, we examined how olfactory systems are involved in the recovery of male attraction to female odors following habituation in mice. Presentation with volatile female odors for 5 min induced habituation in males. To evaluate male attraction to familiar volatile female odors, we measured the duration for investigating volatile female odors from the same female mouse, which was presented twice for 5 min with 1-, 3-, or 5-min interval. Intranasal irrigation with ZnSO4 solution almost completely suppressed investigating behavior, indicating that the main olfactory system is indispensable for inducing the attraction to volatile female odors. In contrast, removal of the vomeronasal organ, bilateral lesions of the accessory olfactory bulb (AOB), or pharmacological blockage of neurotransmission in the AOB did not affect the investigation time at the first odor presentation. However, each one of the treatments decreased the investigation time in the second presentation, compared to that in the first presentation, at longer intervals than control treatment, indicating that the disturbance of neurotransmission in the accessory olfactory system delayed the recovery of the attraction attenuated by the first presentation. These results suggest that the accessory olfactory system facilitates the recovery of the attraction to familiar volatile female odors in male mice. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Odors and incontinence: What does the nose know?

    Science.gov (United States)

    Dalton, Pamela; Maute, Christopher

    2018-06-01

    The fear of producing malodors that can be detected by others is a daily cause of anxiety for millions of people with incontinence. For many, the risk-whether real or imagined-that leaked waste products will be detectable by odor is sufficiently concerning to result in limitations on many types of activities. However, worry about personal odors can sensitize our olfactory system and cause us to be more aware of odors that may otherwise not be perceptible. In addition, heightened olfactory attention can often lead to odor misattributions, such as when we erroneously identify our body as the source of an odor that may simply be present in the environment. Odors produced by our bodies (endogenous odors) do enjoy a greater access to emotional brain centers and are processed faster than general odors. Here we provide examples from both everyday life and laboratory studies to explain how and why the olfactory system is unique among our sensory systems and how this knowledge can provide insights to our concerns about smell and incontinence and inform the development of products and solutions for incontinence.

  4. Release of drinking water contaminants and odor impacts caused by green building cross-linked polyethylene (PEX) plumbing systems.

    Science.gov (United States)

    Kelley, Keven M; Stenson, Alexandra C; Dey, Rajarashi; Whelton, Andrew J

    2014-12-15

    Green buildings are increasingly being plumbed with crosslinked polyethylene (PEX) potable water pipe. Tap water quality was investigated at a six month old plumbing system and chemical and odor quality impacts of six PEX pipe brands were examined. Eleven PEX related contaminants were found in the plumbing system; one regulated (toluene) and several unregulated: Antioxidant degradation products, resin solvents, initiator degradation products, or manufacturing aides. Water chemical and odor quality was monitored for new PEX-a, -b and -c pipes with (2 mg/L free chlorine) and without disinfectant over 30 days. Odor and total organic carbon (TOC) levels decreased for all pipes, but odor remained greater than the USA's Environmental Protection Agency's (USEPA) secondary maximum contaminant level. Odors were not attributed to known odorants ethyl-tert-butyl ether (ETBE) or methyl-tert-butyl ether (MTBE). Free chlorine caused odor levels for PEX-a1 pipe to increase from 26 to 75 threshold odor number (TON) on day 3 and affected the rate at which TOC changed for each brand over 30 days. As TOC decreased, the ultraviolet absorbance at 254 nm increased. Pipes consumed as much as 0.5 mg/L as Cl2 during each 3 day stagnation period. Sixteen organic chemicals were identified, including toluene, pyridine, methylene trichloroacetate and 2,4-di-tert-butylphenol. Some were also detected during the plumbing system field investigation. Six brands of PEX pipes sold in the USA and a PEX-a green building plumbing system impacted chemical and drinking water odor quality. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Evaluation of Food Freshness and Locality by Odor Sensor

    Science.gov (United States)

    Koike, Takayuki; Shimada, Koji; Kamimura, Hironobu; Kaneki, Noriaki

    The aim of this study was to investigate whether food freshness and locality can be classified using a food evaluation system consisting four SnO2-semiconductor gas sensors and a solid phase column, into which collecting aroma materials. The temperature of sensors was periodically changed to be in unsteady state and thus, the sensor information was increased. The parameters (in quefrency band) were extracted from sensor information using cepstrum analysis that enable to separate superimposed information on sinusoidal wave. The quefrency was used as parameters for principal component and discriminant analyses (PCA and DCA) to detect food freshness and food localities. We used three kinds of strawberries, people can perceive its odors, passed from one to three days after harvest, and kelps and Ceylon tea, people are hardly to perceive its odor, corrected from five areas as sample. Then, the deterioration of strawberries and localities of kelps and Ceylon teas were visually evaluated using the numerical analyses. While the deteriorations were classified using PCA or DCA, the localities were classified only by DCA. The findings indicate that, although odorant intensity influenced the method detecting food quality, the quefrency obtained from odorant information using cepstrum analysis were available to detect the difference in the freshness and the localities of foods.

  6. Semantic networks for odors and colors in Alzheimer's disease.

    Science.gov (United States)

    Razani, Jill; Chan, Agnes; Nordin, Steven; Murphy, Claire

    2010-05-01

    Impairment in odor-naming ability and in verbal and visual semantic networks raised the hypothesis of a breakdown in the semantic network for odors in Alzheimer's disease (AD). The current study addressed this hypothesis. Twenty-four individuals, half patients with probable AD and half control participants, performed triadic-similarity judgments for odors and colors, separately, which, utilizing the multidimensional scaling (MDS) technique of individual difference scaling analysis (INDSCAL), generated two-dimensional configurations of similarity. The abilities to match odors and colors with written name labels were assessed to investigate disease-related differences in ability to identify and conceptualize the stimuli. In addition, responses on attribute-sorting tasks, requiring the odor and color perceptions to be categorized as one polarity of a certain dimension, were obtained to allow for objective interpretation of the MDS spatial maps. Whereas comparison subjects generated spatial maps based predominantly on relatively abstract characteristics, patients with AD classified odors on perceptual characteristics. The maps for patients with AD also showed disorganized groupings and loose associations between odors. Their normal configurations for colors imply that the patients were able to comprehend the task per se. The data for label matching and for attribute sorting provide further evidence for a disturbance in semantic odor memory in AD. The patients performed poorer than controls on both these odor tasks, implying that the ability to identify and/or conceptualize odors is impaired in AD. The results provide clear evidence for deterioration of the structure of semantic knowledge for odors in AD.

  7. Characteristics of volatile compound emission and odor pollution from municipal solid waste treating/disposal facilities of a city in Eastern China

    DEFF Research Database (Denmark)

    Guo, Hanwen; Duan, Zhenhan; Zhao, Yan

    2017-01-01

    Transfer station, incineration plant, and landfill site made up the major parts of municipal solid waste disposal system of S city in Eastern China. Characteristics of volatile compounds (VCs) and odor pollution of each facility were investigated from a systematic perspective. Also major index...... in the waste tipping port of the incineration plant. A positive correlation between the olfactory and chemical odor concentrations was found with R2 = 0.918 (n = 15, P technology to deal...... with the non-source-separated waste. Strong attention thus needs to be paid on the enclosed systems in incineration plant to avoid any accidental odor emission....

  8. Odors: appetizing or satiating? Development of appetite during odor exposure over time.

    Science.gov (United States)

    Ramaekers, M G; Boesveldt, S; Lakemond, C M M; van Boekel, M A J S; Luning, P A

    2014-05-01

    Exposure to palatable food odors influences appetite responses, either promoting or inhibiting food intake. Possibly, food odors are appetizing after a short exposure (of circa 1-3 min), but become satiating over time (circa 10-20 min). To investigate the effect of odor exposure on general appetite and sensory-specific appetite (SSA) over time. In a cross-over study, 21 unrestrained women (age: 18-45 years; BMI: 18.5-25 kg m(-2)) were exposed for 20 min to eight different odor types: five food odors, two nonfood odors and no-odor. All odors were distributed in a test room at suprathreshold levels. General appetite, SSA and salivation were measured over time. All food odors significantly increased general appetite and SSA, compared with the no-odor condition. The nonfood odors decreased general appetite. All effects did not change over time during odor exposure. Savory odors increased the appetite for savory foods, but decreased appetite for sweet foods, and vice versa after exposure to sweet odors. Neither food odors nor nonfood odors affected salivation. Palatable food odors were appetizing during and after odor exposure and did not become satiating over a 20-min period. Food odors had a large impact on SSA and a small impact on general appetite. Moreover, exposure to food odors increased the appetite for congruent foods, but decreased the appetite for incongruent foods. It may be hypothesized that, once the body is prepared for intake of a certain food with a particular macronutrient composition, it is unfavorable to consume foods that are very different from the cued food.

  9. Odor-Sensing System to Support Social Participation of People Suffering from Incontinence

    Directory of Open Access Journals (Sweden)

    Alvaro Ortiz Pérez

    2016-12-01

    Full Text Available This manuscript describes the design considerations, implementation, and laboratory validation of an odor sensing module whose purpose is to support people that suffer from incontinence. Because of the requirements expressed by the affected end-users the odor sensing unit is realized as a portable accessory that may be connected to any pre-existing smart device. We have opted for a low-cost, low-power consuming metal oxide based gas detection approach to highlight the viability of developing an inexpensive yet helpful odor recognition technology. The system consists of a hotplate employing, inkjet-printed p-type semiconducting layers of copper(II oxide, and chromium titanium oxide. Both functional layers are characterized with respect to their gas-sensitive behavior towards humidity, ammonia, methylmercaptan, and dimethylsulfide and we demonstrate detection limits in the parts-per-billion range for the two latter gases. Employing a temperature variation scheme that reads out the layer’s resistivity in a steady-state, we use each sensor chip as a virtual array. With this setup, we demonstrate the feasibility of detecting odors associated with incontinence.

  10. Odor-Sensing System to Support Social Participation of People Suffering from Incontinence.

    Science.gov (United States)

    Ortiz Pérez, Alvaro; Kallfaß-de Frenes, Vera; Filbert, Alexander; Kneer, Janosch; Bierer, Benedikt; Held, Pirmin; Klein, Philipp; Wöllenstein, Jürgen; Benyoucef, Dirk; Kallfaß, Sigrid; Mescheder, Ulrich; Palzer, Stefan

    2016-12-29

    This manuscript describes the design considerations, implementation, and laboratory validation of an odor sensing module whose purpose is to support people that suffer from incontinence. Because of the requirements expressed by the affected end-users the odor sensing unit is realized as a portable accessory that may be connected to any pre-existing smart device. We have opted for a low-cost, low-power consuming metal oxide based gas detection approach to highlight the viability of developing an inexpensive yet helpful odor recognition technology. The system consists of a hotplate employing, inkjet-printed p-type semiconducting layers of copper(II) oxide, and chromium titanium oxide. Both functional layers are characterized with respect to their gas-sensitive behavior towards humidity, ammonia, methylmercaptan, and dimethylsulfide and we demonstrate detection limits in the parts-per-billion range for the two latter gases. Employing a temperature variation scheme that reads out the layer's resistivity in a steady-state, we use each sensor chip as a virtual array. With this setup, we demonstrate the feasibility of detecting odors associated with incontinence.

  11. Child Odors and Parenting: A Survey Examination of the Role of Odor in Child-Rearing.

    Science.gov (United States)

    Okamoto, Masako; Shirasu, Mika; Fujita, Rei; Hirasawa, Yukei; Touhara, Kazushige

    2016-01-01

    Parental caregiving is critical for the survival of our young and continuation of our species. In humans, visual and auditory signals from offspring have been shown to be potent facilitators of parenting. However, whether odors emitted by our young also influence human parenting remains unclear. To explore this, we conducted a series of questionnaire surveys targeting parents with children under 6 years old. First, we collected episodes on experiencing odors/sniffing various parts of a child's body (n = 507). The prevalence of experiencing events described in those episodes was examined in a separate survey (n = 384). Based on those results, the Child Odor in Parenting scale (COPs) was developed, and subsequently used in the main survey (n = 888). We found COPs to have adequate content validity, concurrent validity, and reliability. Responses to the COPs demonstrated that parents, especially mothers with infants, are aware of odors from their offspring, and actively seek them in daily child-rearing. The factor structure and content of the COPs items indicated that child odors have both affective and instrumental roles. Affective experiences induce loving feeling and affectionate sniffing, while instrumental experiences pertain to specific hygienic needs. The head was the most frequent source of affective experiences, and the child's bottom of instrumental. Each was experienced by more than 90% of the mothers with a child below 1 year of age. Affective experiences significantly declined as the child grew older, possibly associated with the decline of physical proximity between parents and child. This age-related decline was not prominent for instrumental experiences, except for the bottom, which significantly declined after 3 years of age. The present findings suggest that child odors play roles in human parenting, and that their nature and significance change during the course of a child's development.

  12. Child Odors and Parenting: A Survey Examination of the Role of Odor in Child-Rearing.

    Directory of Open Access Journals (Sweden)

    Masako Okamoto

    Full Text Available Parental caregiving is critical for the survival of our young and continuation of our species. In humans, visual and auditory signals from offspring have been shown to be potent facilitators of parenting. However, whether odors emitted by our young also influence human parenting remains unclear. To explore this, we conducted a series of questionnaire surveys targeting parents with children under 6 years old. First, we collected episodes on experiencing odors/sniffing various parts of a child's body (n = 507. The prevalence of experiencing events described in those episodes was examined in a separate survey (n = 384. Based on those results, the Child Odor in Parenting scale (COPs was developed, and subsequently used in the main survey (n = 888. We found COPs to have adequate content validity, concurrent validity, and reliability. Responses to the COPs demonstrated that parents, especially mothers with infants, are aware of odors from their offspring, and actively seek them in daily child-rearing. The factor structure and content of the COPs items indicated that child odors have both affective and instrumental roles. Affective experiences induce loving feeling and affectionate sniffing, while instrumental experiences pertain to specific hygienic needs. The head was the most frequent source of affective experiences, and the child's bottom of instrumental. Each was experienced by more than 90% of the mothers with a child below 1 year of age. Affective experiences significantly declined as the child grew older, possibly associated with the decline of physical proximity between parents and child. This age-related decline was not prominent for instrumental experiences, except for the bottom, which significantly declined after 3 years of age. The present findings suggest that child odors play roles in human parenting, and that their nature and significance change during the course of a child's development.

  13. Odor Classification using Agent Technology

    Directory of Open Access Journals (Sweden)

    Sigeru OMATU

    2014-03-01

    Full Text Available In order to measure and classify odors, Quartz Crystal Microbalance (QCM can be used. In the present study, seven QCM sensors and three different odors are used. The system has been developed as a virtual organization of agents using an agent platform called PANGEA (Platform for Automatic coNstruction of orGanizations of intElligent Agents. This is a platform for developing open multi-agent systems, specifically those including organizational aspects. The main reason for the use of agents is the scalability of the platform, i.e. the way in which it models the services. The system models functionalities as services inside the agents, or as Service Oriented Approach (SOA architecture compliant services using Web Services. This way the adaptation of the odor classification systems with new algorithms, tools and classification techniques is allowed.

  14. Vaginal Odor

    Science.gov (United States)

    ... normally occurring vaginal bacteria — is the most common vaginal infection that causes a vaginal odor. Trichomoniasis — a sexually transmitted infection — also can lead to vaginal odor. Chlamydia and gonorrhea infections usually don't cause vaginal odors. Neither do ...

  15. Effects of visual priming on taste-odor interaction.

    Directory of Open Access Journals (Sweden)

    Marije van Beilen

    Full Text Available Little is known about the influence of visual characteristics other than colour on flavor perception, and the complex interactions between more than two sensory modalities. This study focused on the effects of recognizability of visual (texture information on flavor perception of odorized sweet beverages. Participants rated the perceived sweetness of odorized sucrose solutions in the presence or absence of either a congruent or incongruent visual context. Odors were qualitatively reminiscent of sweet foods (strawberry and caramel or not (savoury. Visual context was either an image of the same sweet foods (figurative context or a visual texture derived from this product (non-figurative context. Textures were created using a texture synthesis method that preserved perceived food qualities while removing object information. Odor-taste combinations were rated sweeter within a figurative than a non-figurative context. This behaviour was exhibited for all odor-taste combinations, even in trials without images, indicating sustained priming by figurative visual context. A non-figurative context showed a transient sweetening effect. Sweetness was generally enhanced most by the strawberry odor. We conclude that the degree of recognizability of visual information (figurative versus non-figurative, influences flavor perception differently. Our results suggest that this visual context priming is mediated by separate sustained and transient processes that are differently evoked by figurative and non-figurative visual contexts. These components operate independent of the congruency of the image-odor-taste combinations.

  16. Influence of the Chemical Structure on Odor Qualities and Odor Thresholds of Halogenated Guaiacol-Derived Odorants

    Directory of Open Access Journals (Sweden)

    Florian Juhlke

    2017-12-01

    Full Text Available Chlorinated guaiacol derivatives are found in waste water of pulp mills using chlorine in the bleaching process of wood pulp. They can also be detected in fish tissue, possibly causing off-odors. To date, there is no systematic investigation on the odor properties of halogenated guaiacol derivatives. To close this gap, odor thresholds in air and odor qualities of 14 compounds were determined by gas chromatography-olfactometry. Overall, the investigated compounds elicited smells that are characteristic for guaiacol, namely smoky, sweet, vanilla-like, but also medicinal and plaster-like. Their odor thresholds in air were, however, very low, ranging from 0.00072 to 23 ng/Lair. The lowest thresholds were found for 5-chloro- and 5-bromoguaiacol, followed by 4,5-dichloro- and 6-chloroguaiacol. Moreover, some inter-individual differences in odor threshold values could be observed, with the highest variations having been recorded for the individual values of 5-iodo- and 4-bromoguaiacol.

  17. Influence of the chemical structure on odor qualities and odor thresholds of halogenated guaiacol-derived odorants

    Science.gov (United States)

    Juhlke, Florian; Lorber, Katja; Wagenstaller, Maria; Buettner, Andrea

    2017-12-01

    Chlorinated guaiacol derivatives are found in waste water of pulp mills using chlorine in the bleaching process of wood pulp. They can also be detected in fish tissue, possibly causing off-odors. To date, there is no systematic investigation on the odor properties of halogenated guaiacol derivatives. To close this gap, odor thresholds in air and odor qualities of 14 compounds were determined by gas chromatography-olfactometry. Overall, the investigated compounds elicited smells that are characteristic for guaiacol, namely smoky, sweet, vanilla-like, but also medicinal and plaster-like. Their odor thresholds in air were, however, very low, ranging from 0.00072 to 23 ng/Lair. The lowest thresholds were found for 5-chloro- and 5-bromoguaiacol, followed by 4,5-dichloro- and 6-chloroguaiacol. Moreover, some inter-individual differences in odor threshold values could be observed, with the highest variations having been recorded for the individual values of 5-iodo- and 4-bromoguaiacol.

  18. Segregation of odor identity and intensity during odor discrimination in Drosophila mushroom body.

    Science.gov (United States)

    Xia, Shouzhen; Tully, Tim

    2007-10-02

    Molecular and cellular studies have begun to unravel a neurobiological basis of olfactory processing, which appears conserved among vertebrate and invertebrate species. Studies have shown clearly that experience-dependent coding of odor identity occurs in "associative" olfactory centers (the piriform cortex in mammals and the mushroom body [MB] in insects). What remains unclear, however, is whether associative centers also mediate innate (spontaneous) odor discrimination and how ongoing experience modifies odor discrimination. Here we show in naïve flies that Galphaq-mediated signaling in MB modulates spontaneous discrimination of odor identity but not odor intensity (concentration). In contrast, experience-dependent modification (conditioning) of both odor identity and intensity occurs in MB exclusively via Galphas-mediated signaling. Our data suggest that spontaneous responses to odor identity and odor intensity discrimination are segregated at the MB level, and neural activity from MB further modulates olfactory processing by experience-independent Galphaq-dependent encoding of odor identity and by experience-induced Galphas-dependent encoding of odor intensity and identity.

  19. Analysis of odorous gases with simultaneous GC-MS and sensory determination

    Energy Technology Data Exchange (ETDEWEB)

    Orko, I.; Lehtomaeki, J.; Sandell, E.; Arnold, M. [VTT Chemical Technology, Espoo (Finland). Environmental Technology

    1995-12-31

    Industrial odorous off-gases can consist of hundreds of different compounds giving cause to odour annoyance in the vicinity of the odour-emitting plant. For the identification of the odorous components in the gas, traditional analytical methods are not always sufficient since the odour threshold values cannot often be found in literature. This report describes the development of a GC-MS sniffing port method for identifying odorous compounds in off-gases. In the method the sample is injected into a gas chromatograph and divided into two flows. The compounds in these sample flows are separated in two identical columns and detected simultaneously in a mass spectrometer and by sensory means. The olfactory detections are marked in the iongram and the odorous compounds are identified. Tenax TA adsorbent is generally used for collecting the odorous sample for analysis. The compounds are released from the adsorbent for analysis by thermal desorption. The report also describes a case study where the GC-MS sniffing port method was applied to a gaseous emission from a food factory. Over ten odorous compounds could be identified. (author)

  20. Effects of Odor on Emotion, with Implications

    Directory of Open Access Journals (Sweden)

    Mikiko eKadohisa

    2013-10-01

    Full Text Available The sense of smell is found widely in the animal kingdom. Human and animal studies show that odor perception is modulated by experience and/or physiological state (such as hunger, and that some odors can arouse emotion, and can lead to the recall of emotional memories. Further, odors can influence psychological and physiological states. Individual odorants are mapped via gene-specified receptors to corresponding glomeruli in the olfactory bulb, which directly projects to the piriform cortex and the amygdala without a thalamic relay. The odors to which a glomerulus responds reflect the chemical structure of the odorant. The piriform cortex and the amygdala both project to the orbitofrontal cortex which with the amygdala is involved in emotion and associative learning, and to the entorhinal/hippocampal system which is involved in long-term memory including episodic memory. Evidence that some odors can modulate emotion and cognition is described, and the possible implications for the treatment of psychological problems, for example in reducing the effects of stress, are considered.

  1. Segregation of odor identity and intensity during odor discrimination in Drosophila mushroom body.

    Directory of Open Access Journals (Sweden)

    Shouzhen Xia

    2007-10-01

    Full Text Available Molecular and cellular studies have begun to unravel a neurobiological basis of olfactory processing, which appears conserved among vertebrate and invertebrate species. Studies have shown clearly that experience-dependent coding of odor identity occurs in "associative" olfactory centers (the piriform cortex in mammals and the mushroom body [MB] in insects. What remains unclear, however, is whether associative centers also mediate innate (spontaneous odor discrimination and how ongoing experience modifies odor discrimination. Here we show in naïve flies that Galphaq-mediated signaling in MB modulates spontaneous discrimination of odor identity but not odor intensity (concentration. In contrast, experience-dependent modification (conditioning of both odor identity and intensity occurs in MB exclusively via Galphas-mediated signaling. Our data suggest that spontaneous responses to odor identity and odor intensity discrimination are segregated at the MB level, and neural activity from MB further modulates olfactory processing by experience-independent Galphaq-dependent encoding of odor identity and by experience-induced Galphas-dependent encoding of odor intensity and identity.

  2. The olfactory tubercle encodes odor valence in behaving mice.

    Science.gov (United States)

    Gadziola, Marie A; Tylicki, Kate A; Christian, Diana L; Wesson, Daniel W

    2015-03-18

    Sensory information acquires meaning to adaptively guide behaviors. Despite odors mediating a number of vital behaviors, the components of the olfactory system responsible for assigning meaning to odors remain unclear. The olfactory tubercle (OT), a ventral striatum structure that receives monosynaptic input from the olfactory bulb, is uniquely positioned to transform odor information into behaviorally relevant neural codes. No information is available, however, on the coding of odors among OT neurons in behaving animals. In recordings from mice engaged in an odor discrimination task, we report that the firing rate of OT neurons robustly and flexibly encodes the valence of conditioned odors over identity, with rewarded odors evoking greater firing rates. This coding of rewarded odors occurs before behavioral decisions and represents subsequent behavioral responses. We predict that the OT is an essential region whereby odor valence is encoded in the mammalian brain to guide goal-directed behaviors. Copyright © 2015 the authors 0270-6474/15/354515-13$15.00/0.

  3. A Local Weighted Nearest Neighbor Algorithm and a Weighted and Constrained Least-Squared Method for Mixed Odor Analysis by Electronic Nose Systems

    Directory of Open Access Journals (Sweden)

    Jyuo-Min Shyu

    2010-11-01

    Full Text Available A great deal of work has been done to develop techniques for odor analysis by electronic nose systems. These analyses mostly focus on identifying a particular odor by comparing with a known odor dataset. However, in many situations, it would be more practical if each individual odorant could be determined directly. This paper proposes two methods for such odor components analysis for electronic nose systems. First, a K-nearest neighbor (KNN-based local weighted nearest neighbor (LWNN algorithm is proposed to determine the components of an odor. According to the component analysis, the odor training data is firstly categorized into several groups, each of which is represented by its centroid. The examined odor is then classified as the class of the nearest centroid. The distance between the examined odor and the centroid is calculated based on a weighting scheme, which captures the local structure of each predefined group. To further determine the concentration of each component, odor models are built by regressions. Then, a weighted and constrained least-squares (WCLS method is proposed to estimate the component concentrations. Experiments were carried out to assess the effectiveness of the proposed methods. The LWNN algorithm is able to classify mixed odors with different mixing ratios, while the WCLS method can provide good estimates on component concentrations.

  4. Mammalian odorant receptor tuning breadth persists across distinct odorant panels.

    Directory of Open Access Journals (Sweden)

    Devin Kepchia

    Full Text Available The molecular receptive range (MRR of a mammalian odorant receptor (OR is the set of odorant structures that activate the OR, while the distribution of these odorant structures across odor space is the tuning breadth of the OR. Variation in tuning breadth is thought to be an important property of ORs, with the MRRs of these receptors varying from narrowly to broadly tuned. However, defining the tuning breadth of an OR is a technical challenge. For practical reasons, a screening panel that broadly covers odor space must be limited to sparse coverage of the many potential structures in that space. When screened with such a panel, ORs with different odorant specificities, but equal tuning breadths, might appear to have different tuning breadths due to chance. We hypothesized that ORs would maintain their tuning breadths across distinct odorant panels. We constructed a new screening panel that was broadly distributed across an estimated odor space and contained compounds distinct from previous panels. We used this new screening panel to test several murine ORs that were previously characterized as having different tuning breadths. ORs were expressed in Xenopus laevis oocytes and assayed by two-electrode voltage clamp electrophysiology. MOR256-17, an OR previously characterized as broadly tuned, responded to nine novel compounds from our new screening panel that were structurally diverse and broadly dispersed across an estimated odor space. MOR256-22, an OR previously characterized as narrowly tuned, responded to a single novel compound that was structurally similar to a previously known ligand for this receptor. MOR174-9, a well-characterized receptor with a narrowly tuned MRR, did not respond to any novel compounds in our new panel. These results support the idea that variation in tuning breadth among these three ORs is not an artifact of the screening protocol, but is an intrinsic property of the receptors.

  5. The neurobiology of infant maternal odor learning

    Directory of Open Access Journals (Sweden)

    C. Raineki

    2010-10-01

    Full Text Available Infant rats must learn to identify their mother’s diet-dependent odor. Once learned, maternal odor controls pups’ approach to the mother, their social behavior and nipple attachment. Here we present a review of the research from four different laboratories, which suggests that neural and behavioral responses to the natural maternal odor and neonatal learned odors are similar. Together, these data indicate that pups have a unique learning circuit relying on the olfactory bulb for neural plasticity and on the hyperfunctioning noradrenergic locus coeruleus flooding the olfactory bulb with norepinephrine to support the neural changes. Another important factor making this system unique is the inability of the amygdala to become incorporated into the infant learning circuit. Thus, infant rats appear to be primed in early life to learn odors that will evoke approach responses supporting attachment to the caregiver.

  6. Immunization alters body odor.

    Science.gov (United States)

    Kimball, Bruce A; Opiekun, Maryanne; Yamazaki, Kunio; Beauchamp, Gary K

    2014-04-10

    Infections have been shown to alter body odor. Because immune activation accompanies both infection and immunization, we tested the hypothesis that classical immunization might similarly result in the alteration of body odors detectable by trained biosensor mice. Using a Y-maze, we trained biosensor mice to distinguish between urine odors from rabies-vaccinated (RV) and unvaccinated control mice. RV-trained mice generalized this training to mice immunized with the equine West Nile virus (WNV) vaccine compared with urine of corresponding controls. These results suggest that there are similarities between body odors of mice immunized with these two vaccines. This conclusion was reinforced when mice could not be trained to directly discriminate between urine odors of RV- versus WNV-treated mice. Next, we trained biosensor mice to discriminate the urine odors of mice treated with lipopolysaccharide (LPS; a general elicitor of innate immunological responses) from the urine of control mice. These LPS-trained biosensors could distinguish between the odors of LPS-treated mouse urine and RV-treated mouse urine. Finally, biosensor mice trained to distinguish between the odors of RV-treated mouse urine and control mouse urine did not generalize this training to discriminate between the odors of LPS-treated mouse urine and control mouse urine. From these experiments, we conclude that: (1) immunization alters urine odor in similar ways for RV and WNV immunizations; and (2) immune activation with LPS also alters urine odor but in ways different from those of RV and WNV. Published by Elsevier Inc.

  7. Efficacy of Odor Scavengers in Reducing Odor Compounds in Water, Milk, and Soymilk

    OpenAIRE

    Norton, Jenny Lynn

    2003-01-01

    Odor detection thresholds of hexanal, 2-heptenal, 2-pentanone, and 2,4-nonadienal were determined in spring water, high temperature short time (HTST) 2% fat milk, and extended shelf life soymilk. The efficacy of odor scavenger's beta-cyclodextrin, D-sorbitol, and nylon 6 in removing these odors was also determined. The odor thresholds of the different odor and media combinations were as follows: hexanal in spring water, milk, and soymilk were 585, 339, and 536 ppb respectively; 2-heptenal ...

  8. Odor-evoked inhibition of olfactory sensory neurons drives olfactory perception in Drosophila.

    Science.gov (United States)

    Cao, Li-Hui; Yang, Dong; Wu, Wei; Zeng, Xiankun; Jing, Bi-Yang; Li, Meng-Tong; Qin, Shanshan; Tang, Chao; Tu, Yuhai; Luo, Dong-Gen

    2017-11-07

    Inhibitory response occurs throughout the nervous system, including the peripheral olfactory system. While odor-evoked excitation in peripheral olfactory cells is known to encode odor information, the molecular mechanism and functional roles of odor-evoked inhibition remain largely unknown. Here, we examined Drosophila olfactory sensory neurons and found that inhibitory odors triggered outward receptor currents by reducing the constitutive activities of odorant receptors, inhibiting the basal spike firing in olfactory sensory neurons. Remarkably, this odor-evoked inhibition of olfactory sensory neurons elicited by itself a full range of olfactory behaviors from attraction to avoidance, as did odor-evoked olfactory sensory neuron excitation. These results indicated that peripheral inhibition is comparable to excitation in encoding sensory signals rather than merely regulating excitation. Furthermore, we demonstrated that a bidirectional code with both odor-evoked inhibition and excitation in single olfactory sensory neurons increases the odor-coding capacity, providing a means of efficient sensory encoding.

  9. Minimal olfactory perception during sleep: why odor alarms will not work for humans.

    Science.gov (United States)

    Carskadon, Mary A; Herz, Rachel S

    2004-05-01

    To examine olfactory arousal threshold during sleep in comparison to an auditory tone. On night 1, participants rated odor intensity when awake and experienced olfactory stimuli during stage 1 sleep. Night 2 involved stage 2, stage 4, and rapid-eye-movement (REM) sleep trials using the "staircase" threshold-detection method. Electroencephalogram, electrooculogram, electromyogram, electrocardiogram, and respiration were recorded along with behavioral response. An 800-Hz tone was given on trials when odors failed to arouse. Participants slept in individual rooms. Stimulus-delivery systems were operated from a separate room, where an experimenter observed physiologic recordings and behavioral responses. Three healthy men and 3 women aged 20 to 25 years (mean, 22 years). Two odorants, peppermint and pyridine, at 4 concentrations were presented through nasal cannulas using an air-dilution olfactometer. Tones were played over a speaker. Behavioral (button press and oral) responses, electroencephalographic activation, and changes in breathing and heart rate were assessed. Participants responded to odors on 92% of stage 1 sleep trials. Peppermint was ineffective in stages 2, 4, and REM sleep. Pyridine produced behavioral threshold on 45% of stage 2 trials, none in stage 4, and one third of REM sleep trials. Tones were effective on at least 75% of trials. Heart rate increased significantly only following behavioral responses to odors or tones across sleep stages. The data indicate that human olfaction is not reliably capable of alerting a sleeper.

  10. Collective Odor Source Estimation and Search in Time-Variant Airflow Environments Using Mobile Robots

    Science.gov (United States)

    Meng, Qing-Hao; Yang, Wei-Xing; Wang, Yang; Zeng, Ming

    2011-01-01

    This paper addresses the collective odor source localization (OSL) problem in a time-varying airflow environment using mobile robots. A novel OSL methodology which combines odor-source probability estimation and multiple robots’ search is proposed. The estimation phase consists of two steps: firstly, the separate probability-distribution map of odor source is estimated via Bayesian rules and fuzzy inference based on a single robot’s detection events; secondly, the separate maps estimated by different robots at different times are fused into a combined map by way of distance based superposition. The multi-robot search behaviors are coordinated via a particle swarm optimization algorithm, where the estimated odor-source probability distribution is used to express the fitness functions. In the process of OSL, the estimation phase provides the prior knowledge for the searching while the searching verifies the estimation results, and both phases are implemented iteratively. The results of simulations for large-scale advection–diffusion plume environments and experiments using real robots in an indoor airflow environment validate the feasibility and robustness of the proposed OSL method. PMID:22346650

  11. Odors generated from the Maillard reaction affect autonomic nervous activity and decrease blood pressure through the olfactory system.

    Science.gov (United States)

    Zhou, Lanxi; Ohata, Motoko; Owashi, Chisato; Nagai, Katsuya; Yokoyama, Issei; Arihara, Keizo

    2018-02-01

    Systolic blood pressure (SBP) of rats decreases significantly following exposure to the odor generated from the Maillard reaction of protein digests with xylose. This study identified active odorants that affect blood pressure and demonstrated the mechanism of action. Among the four potent odorants that contribute most to the odor of the Maillard reaction sample, 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) and 5-methyl-2-pyrazinemethanol (MPM) decreased SBP significantly. The earliest decrease in blood pressure was observed 5 min after exposure to DMHF. Application of zinc sulfate to the nasal cavity eliminated the effect. Furthermore, gastric vagal (parasympathetic) nerve activity was elevated and renal sympathetic nerve activity was lowered after exposure to DMHF. It is indicated that DMHF affects blood pressure through the olfactory system, and the mechanism for the effect of DMHF on blood pressure involves the autonomic nervous system. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  12. DESIGN MANUAL: ODOR AND CORROSION CONTROL IN SANITARY SEWERAGE SYSTEMS AND TREATMENT PLANTS

    Science.gov (United States)

    Wastewater is known to the public for its potential to create odor nuisance. Sometimes it is the odors escaping from sewer manholes that cause complaints; more commonly, the odor source is a wastewater treatment facility. Yet there are wastewater treatment facilities that are fr...

  13. Avian influenza infection alters fecal odor in mallards.

    Directory of Open Access Journals (Sweden)

    Bruce A Kimball

    Full Text Available Changes in body odor are known to be a consequence of many diseases. Much of the published work on disease-related and body odor changes has involved parasites and certain cancers. Much less studied have been viral diseases, possibly due to an absence of good animal model systems. Here we studied possible alteration of fecal odors in animals infected with avian influenza viruses (AIV. In a behavioral study, inbred C57BL/6 mice were trained in a standard Y-maze to discriminate odors emanating from feces collected from mallard ducks (Anas platyrhynchos infected with low-pathogenic avian influenza virus compared to fecal odors from non-infected controls. Mice could discriminate odors from non-infected compared to infected individual ducks on the basis of fecal odors when feces from post-infection periods were paired with feces from pre-infection periods. Prompted by this indication of odor change, fecal samples were subjected to dynamic headspace and solvent extraction analyses employing gas chromatography/mass spectrometry to identify chemical markers indicative of AIV infection. Chemical analyses indicated that AIV infection was associated with a marked increase of acetoin (3-hydroxy-2-butanone in feces. These experiments demonstrate that information regarding viral infection exists via volatile metabolites present in feces. Further, they suggest that odor changes following virus infection could play a role in regulating behavior of conspecifics exposed to infected individuals.

  14. The insular taste cortex contributes to odor quality coding

    Directory of Open Access Journals (Sweden)

    Maria G Veldhuizen

    2010-07-01

    Full Text Available Despite distinct peripheral and central pathways, stimulation of both the olfactory and the gustatory systems may give rise to the sensation of sweetness. Whether there is a common central mechanism producing sweet quality sensations or two discrete mechanisms associated independently with gustatory and olfactory stimuli is currently unknown. Here we used fMRI to determine whether odor sweetness is represented in the piriform olfactory cortex, which is thought to code odor quality, or in the insular taste cortex, which is thought to code taste quality. Fifteen participants sampled two concentrations of a pure sweet taste (sucrose, two sweet food odors (chocolate and strawberry, and two sweet floral odors (lilac and rose. Replicating prior work we found that olfactory stimulation activated the piriform, orbitofrontal and insular cortices. Of these regions, only the insula also responded to sweet taste. More importantly, the magnitude of the response to the food odors, but not to the non-food odors, in this region of insula was positively correlated with odor sweetness rating. These findings demonstrate that insular taste cortex contributes to odor quality coding by representing the taste-like aspects of food odors. Since the effect was specific to the food odors, and only food odors are experienced with taste, we suggest this common central mechanism develops as a function of experiencing flavors.

  15. Psychological and physiological responses to odor-evoked autobiographic memory.

    Science.gov (United States)

    Matsunaga, Masahiro; Isowa, Tokiko; Yamakawa, Kaori; Kawanishi, Yoko; Tsuboi, Hirohito; Kaneko, Hiroshi; Sadato, Norihiro; Oshida, Akiko; Katayama, Atsushi; Kashiwagi, Mitsuyoshi; Ohira, Hideki

    2011-01-01

    The "Proust phenomenon" occurs when a certain smell evokes a specific memory. Recent studies have demonstrated that odor-evoked autobiographic memories are more emotional than those elicited by other sensory stimuli because of the direct neural communication between the olfactory system and the amygdala. The amygdala is known to regulate various physiological activities including the endocrine and immune systems; therefore, odor-evoked autobiographic memory may trigger various psychological and physiological responses; however, the responses elicited by this memory remains obscure. In this study, we aimed to investigate the psychological and physiological responses accompanying odor-evoked autobiographic memory. We recruited healthy male and female volunteers and investigated changes in their mood states and autonomic nervous, endocrine, and immune activities when autobiographic memory was evoked in the participants by asking them to smell an odor(s) that was nostalgic to them. The autobiographic memories associated with positive emotion resulted in increased positive mood states, such as comfort and happiness, and decreased negative mood states, such as anxiety. Furthermore, heart rate was decreased, skin-conductance level was increased, and peripheral interleukin-2 level was decreased after smelling the nostalgic odor. These psychological and physiological responses were significantly correlated. The present study suggests that odor-evoked autobiographic memory along with a positive feeling induce various physiological responses, including the autonomic nervous and immune activities. To the best of our knowledge, the present study is the first to observe an interaction between odor-evoked autobiographic memories and immune function.

  16. Numerical simulations of odorant detection by biologically inspired sensor arrays

    International Nuclear Information System (INIS)

    Schuech, R; Stacey, M T; Barad, M F; Koehl, M A R

    2012-01-01

    The antennules of many marine crustaceans enable them to rapidly locate sources of odorant in turbulent environmental flows and may provide biological inspiration for engineered plume sampling systems. A substantial gap in knowledge concerns how the physical interaction between a sensing device and the chemical filaments forming a turbulent plume affects odorant detection and filters the information content of the plume. We modeled biological arrays of chemosensory hairs as infinite arrays of odorant flux-detecting cylinders and simulated the fluid flow around and odorant flux into the hair-like sensors as they intercepted a single odorant filament. As array geometry and sampling kinematics were varied, we quantified distortion of the flux time series relative to the spatial shape of the original odorant filament as well as flux metrics that may be important to both organisms and engineered systems attempting to measure plume structure and/or identify chemical composition. The most important predictor of signal distortion is the ratio of sensor diameter to odorant filament width. Achieving high peak properties (e.g. sharpness) of the flux time series and maximizing the total number of odorant molecules detected appear to be mutually exclusive design goals. Sensor arrays inspired specifically by the spiny lobster Panulirus argus and mantis shrimp Gonodactylaceus falcatus introduce little signal distortion but these species' neural systems may not be able to resolve plume structure at the level of individual filaments via temporal properties of the odorant flux. Current chemical sensors are similarly constrained. Our results suggest either that the spatial distribution of flux across the aesthetasc array is utilized by P. argus and G. falcatus, or that such high spatiotemporal resolution is unnecessary for effective plume tracking.

  17. Expressing exogenous functional odorant receptors in cultured olfactory sensory neurons

    Directory of Open Access Journals (Sweden)

    Fomina Alla F

    2008-09-01

    Full Text Available Abstract Background Olfactory discrimination depends on the large numbers of odorant receptor genes and differential ligand-receptor signaling among neurons expressing different receptors. In this study, we describe an in vitro system that enables the expression of exogenous odorant receptors in cultured olfactory sensory neurons. Olfactory sensory neurons in the culture express characteristic signaling molecules and, therefore, provide a system to study receptor function within its intrinsic cellular environment. Results We demonstrate that cultured olfactory sensory neurons express endogenous odorant receptors. Lentiviral vector-mediated gene transfer enables successful ectopic expression of odorant receptors. We show that the ectopically expressed mouse I7 is functional in the cultured olfactory sensory neurons. When two different odorant receptors are ectopically expressed simultaneously, both receptor proteins co-localized in the same olfactory sensory neurons up to 10 days in vitro. Conclusion This culture technique provided an efficient method to culture olfactory sensory neurons whose morphology, molecular characteristics and maturation progression resembled those observed in vivo. Using this system, regulation of odorant receptor expression and its ligand specificity can be studied in its intrinsic cellular environment.

  18. Odors: appetizing or satiating? Development of appetite during odor exposure over time

    NARCIS (Netherlands)

    Ramaekers, M.G.; Boesveldt, S.; Lakemond, C.M.M.; Boekel, van M.A.J.S.; Luning, P.A.

    2014-01-01

    Background: Exposure to palatable food odors influences appetite responses, either promoting or inhibiting food intake. Possibly, food odors are appetizing after a short exposure (of circa 1–3¿min), but become satiating over time (circa 10–20¿min). Objective: To investigate the effect of odor

  19. Insights into structural features determining odorant affinities to honey bee odorant binding protein 14.

    Science.gov (United States)

    Schwaighofer, Andreas; Pechlaner, Maria; Oostenbrink, Chris; Kotlowski, Caroline; Araman, Can; Mastrogiacomo, Rosa; Pelosi, Paolo; Knoll, Wolfgang; Nowak, Christoph; Larisika, Melanie

    2014-04-18

    Molecular interactions between odorants and odorant binding proteins (OBPs) are of major importance for understanding the principles of selectivity of OBPs towards the wide range of semiochemicals. It is largely unknown on a structural basis, how an OBP binds and discriminates between odorant molecules. Here we examine this aspect in greater detail by comparing the C-minus OBP14 of the honey bee (Apis mellifera L.) to a mutant form of the protein that comprises the third disulfide bond lacking in C-minus OBPs. Affinities of structurally analogous odorants featuring an aromatic phenol group with different side chains were assessed based on changes of the thermal stability of the protein upon odorant binding monitored by circular dichroism spectroscopy. Our results indicate a tendency that odorants show higher affinity to the wild-type OBP suggesting that the introduced rigidity in the mutant protein has a negative effect on odorant binding. Furthermore, we show that OBP14 stability is very sensitive to the position and type of functional groups in the odorant. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Health effects of indoor odorants.

    Science.gov (United States)

    Cone, J E; Shusterman, D

    1991-11-01

    People assess the quality of the air indoors primarily on the basis of its odors and on their perception of associated health risk. The major current contributors to indoor odorants are human occupant odors (body odor), environmental tobacco smoke, volatile building materials, bio-odorants (particularly mold and animal-derived materials), air fresheners, deodorants, and perfumes. These are most often present as complex mixtures, making measurement of the total odorant problem difficult. There is no current method of measuring human body odor, other than by human panel studies of expert judges of air quality. Human body odors have been quantitated in terms of the "olf" which is the amount of air pollution produced by the average person. Another quantitative unit of odorants is the "decipol," which is the perceived level of pollution produced by the average human ventilated by 10 L/sec of unpolluted air or its equivalent level of dissatisfaction from nonhuman air pollutants. The standard regulatory approach, focusing on individual constituents or chemicals, is not likely to be successful in adequately controlling odorants in indoor air. Besides the current approach of setting minimum ventilation standards to prevent health effects due to indoor air pollution, a standard based on the olf or decipol unit might be more efficacious as well as simpler to measure.

  1. Odor Perception by Dogs: Evaluating Two Training Approaches for Odor Learning of Sniffer Dogs.

    Science.gov (United States)

    Fischer-Tenhagen, Carola; Johnen, Dorothea; Heuwieser, Wolfgang; Becker, Roland; Schallschmidt, Kristin; Nehls, Irene

    2017-06-01

    In this study, a standardized experimental set-up with various combinations of herbs as odor sources was designed. Two training approaches for sniffer dogs were compared; first, training with a pure reference odor, and second, training with a variety of odor mixtures with the target odor as a common denominator. The ability of the dogs to identify the target odor in a new context was tested. Six different herbs (basil, St. John's wort, dandelion, marjoram, parsley, ribwort) were chosen to produce reference materials in various mixtures with (positive) and without (negative) chamomile as the target odor source. The dogs were trained to show 1 of 2 different behaviors, 1 for the positive, and 1 for the negative sample as a yes/no task. Tests were double blind with one sample presented at a time. In both training approaches, dogs were able to detect chamomile as the target odor in any presented mixture with an average sensitivity of 72% and a specificity of 84%. Dogs trained with odor mixture containing the target odor had more correct indications in the transfer task. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Gestão de odores: fundamentos do Nariz Eletrônico Odor management: fundamentals of Electronic Nose

    Directory of Open Access Journals (Sweden)

    Henrique de Melo Lisboa

    2009-03-01

    Full Text Available Narizes Eletrônicos têm sido desenvolvidos para detecção automática e classificação de odores, vapores e gases. São instrumentos capazes de medir a concentração ou intensidade odorante de modo similar a um olfatômetro, mas sem as limitações inerentes ao uso de painéis humanos, o que é altamente desejável. Um Nariz Eletrônico é geralmente composto por um sistema de sensores químicos e um sistema eletrônico associado à inteligência artificial para reconhecimento. Têm sido aplicados em muitas áreas, tais como análise de alimentos, controles ambientais e diagnósticos médicos. Do ponto de vista ambiental, sistemas de Narizes Eletrônicos vêm sendo usados para monitorar a qualidade do ar, detectar fontes e quantificar emissões odorantes. Este artigo pretende apresentar os fundamentos dos Narizes Eletrônicos.Electronic noses have been developed for automatic detection and classification of odors, vapors and gases. They are instruments capable to identify odors as the human nose does, and measure the odor concentration or intensity according to similar metrics as an olfactometer, but without the inherent limitations of human panels. An Electronic Nose is generally composed of a matrix of chemical sensors and computer based system for odor recognition and classification. It has been applied in many areas, such as food quality analysis, explosives detection, environmental monitoring and medical diagnosis. In the ambient environment, systems of Electronic Noses have been used to monitor the quality of air and to detect and quantify odor sources and emissions. This article intends to present the fundamentals and main characteristics of Electronic Noses.

  3. Predicting the response of olfactory sensory neurons to odor mixtures from single odor response

    Science.gov (United States)

    Marasco, Addolorata; de Paris, Alessandro; Migliore, Michele

    2016-04-01

    The response of olfactory receptor neurons to odor mixtures is not well understood. Here, using experimental constraints, we investigate the mathematical structure of the odor response space and its consequences. The analysis suggests that the odor response space is 3-dimensional, and predicts that the dose-response curve of an odor receptor can be obtained, in most cases, from three primary components with specific properties. This opens the way to an objective procedure to obtain specific olfactory receptor responses by manipulating mixtures in a mathematically predictable manner. This result is general and applies, independently of the number of odor components, to any olfactory sensory neuron type with a response curve that can be represented as a sigmoidal function of the odor concentration.

  4. The functional neuroanatomy of odor evoked autobiographical memories cued by odors and words.

    Science.gov (United States)

    Arshamian, Artin; Iannilli, Emilia; Gerber, Johannes C; Willander, Johan; Persson, Jonas; Seo, Han-Seok; Hummel, Thomas; Larsson, Maria

    2013-01-01

    Behavioral evidence indicates that odor evoked autobiographical memories (OEAMs) are older, more emotional, less thought of and induce stronger time traveling characteristics than autobiographical memories (AMs) evoked by other modalities. The main aim of this study was to explore the neural correlates of AMs evoked by odors as a function of retrieval cue. Participants were screened for specific OEAMs and later presented with the odor cue and its verbal referent in an fMRI paradigm. Because the same OEAM was retrieved across both cue formats (odor and word), potential cue dependent brain activations were investigated. The overall results showed that odor and word cued OEAMs activated regions typically associated with recollection of autobiographical information. Although no odors were presented, a verbal cuing of the OEAMs activated areas associated with olfactory perception (e.g., piriform cortex). However, relative to word cuing, an odor cuing of OEAMs resulted in more activity in MTL regions such as the parahippocampus, and areas involved in visual vividness (e.g., occipital gyrus and precuneus). Furthermore, odor cues activated areas related to emotional processing, such as limbic and tempopolar regions significantly more. In contrast, word cues relative to odor cues recruited a more widespread and bilateral prefrontal activity. Hippocampus activity did not vary as function of the remoteness of the memory, but recollection of OEAMs from the 1(st) vs the 2(nd) decade of life showed specific activation in the right OFC, whereas the 2(nd) reflected a higher activation in the left inferior frontal gyrus. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Nuisance Odors: Is there a Concern - 12340

    Energy Technology Data Exchange (ETDEWEB)

    Brounstein, Robert A. [TerranearPMC, Los Alamos New Mexico 87544 (United States)

    2012-07-01

    standards. Another area of consideration would be whether nuisance odors will need separate and distinct criteria with regards to hazard identification and control. While evidence suggests that odorants do not cause direct toxicological effects to the various biologic systems, they can be influential by initiating symptoms that are associated with known toxins. The difference between the classic toxic systemic reactions and those initiated by nuisance odors can be summarized as one causing a dysfunction of a target organ or system as opposed to triggering a message to the brain which causes a physical reaction. While strong odors may exist at HAZWOPER work sites, their particular risk of pathogenic disease has yet to be established. This leaves many unanswered questions; the most obvious being, 'can an odorous chemical that can result in headaches, nausea, changes in blood pressure, body temperature, etc., be considered a toxin even if biological systems remain unaffected and sampling/monitoring protocol negative stimuli, thereby causing symptomatic experiences; will such disciplines as psychology need to be considered as part of the expertise within the field a environmental and occupational health? In the classic text, 'The Fundamentals of Industrial Hygiene' industrial hygiene has been defined as 'that science and art devoted to the anticipation, recognition, evaluation, and control of those environmental factors or stressors arising in or from the workplace that may cause sickness, impaired health and well-being, or significant discomfort among workers or among the citizens of the community'. Based on this definition, it is indeed the responsibility of the occupational health professional to move forward and to provide an effective program to 'anticipate, recognize, evaluate, and control' such airborne contaminants that may not be adequately controlled based on current knowledge and technology. The question is, 'Is the industrial

  6. Predicting Odor Pleasantness from Odorant Structure: Pleasantness as a Reflection of the Physical World

    Science.gov (United States)

    2009-11-01

    34 ( Engen , 1982). We next reduced the dimensionality of physico-chemical properties, and identified a primary axis of physico-chemical space. This axis...Berglund B, Berglund U, Engen T, Ekman G (1973) Multidimensional Analysis of 21 Odors. Scandinavian Journal of Psychology 14:131-137. Brennan PA...1984) Hedonics of odors and odor descriptors. J AIR POLLUT CONTROL ASSOC 34:752-776. Engen T (1982) The perception of odors. New York: Academic

  7. Recovery of Agricultural Odors and Odorous Compounds from Polyvinyl Fluoride Film Bags

    Science.gov (United States)

    Parker, David B.; Perschbacher-Buser, Zena L.; Cole, N. Andy; Koziel, Jacek A.

    2010-01-01

    Accurate sampling methods are necessary when quantifying odor and volatile organic compound emissions at agricultural facilities. The commonly accepted methodology in the U.S. has been to collect odor samples in polyvinyl fluoride bags (PVF, brand name Tedlar®) and, subsequently, analyze with human panelists using dynamic triangular forced-choice olfactometry. The purpose of this research was to simultaneously quantify and compare recoveries of odor and odorous compounds from both commercial and homemade PVF sampling bags. A standard gas mixture consisting of p-cresol (40 μg m−3) and seven volatile fatty acids: acetic (2,311 μg m−3), propionic (15,800 μg m−3), isobutyric (1,686 μg m−3), butyric (1,049 μg m−3), isovaleric (1,236 μg m−3), valeric (643 μg m−3), and hexanoic (2,158 μg m−3) was placed in the PVF bags at times of 1 h, 1 d, 2 d, 3 d, and 7 d prior to compound and odor concentration analyses. Compound concentrations were quantified using sorbent tubes and gas chromatography/mass spectrometry. Odor concentration, intensity, and hedonic tone were measured using a panel of trained human subjects. Compound recoveries ranged from 2 to 40% after 1 h and 0 to 14% after 7 d. Between 1 h and 7 d, odor concentrations increased by 45% in commercial bags, and decreased by 39% in homemade bags. Minimal changes were observed in intensity and hedonic tone over the same time period. These results suggest that PVF bags can bias individual compound concentrations and odor as measured by dynamic triangular forced-choice olfactometry. PMID:22163671

  8. Odor Discrimination in Drosophila: From Neural Population Codes to Behavior

    Science.gov (United States)

    Parnas, Moshe; Lin, Andrew C.; Huetteroth, Wolf; Miesenböck, Gero

    2013-01-01

    Summary Taking advantage of the well-characterized olfactory system of Drosophila, we derive a simple quantitative relationship between patterns of odorant receptor activation, the resulting internal representations of odors, and odor discrimination. Second-order excitatory and inhibitory projection neurons (ePNs and iPNs) convey olfactory information to the lateral horn, a brain region implicated in innate odor-driven behaviors. We show that the distance between ePN activity patterns is the main determinant of a fly’s spontaneous discrimination behavior. Manipulations that silence subsets of ePNs have graded behavioral consequences, and effect sizes are predicted by changes in ePN distances. ePN distances predict only innate, not learned, behavior because the latter engages the mushroom body, which enables differentiated responses to even very similar odors. Inhibition from iPNs, which scales with olfactory stimulus strength, enhances innate discrimination of closely related odors, by imposing a high-pass filter on transmitter release from ePN terminals that increases the distance between odor representations. PMID:24012006

  9. Do Valenced Odors and Trait Body Odor Disgust Affect Evaluation of Emotion in Dynamic Faces?

    Science.gov (United States)

    Syrjänen, Elmeri; Liuzza, Marco Tullio; Fischer, Håkan; Olofsson, Jonas K

    2017-12-01

    Disgust is a core emotion evolved to detect and avoid the ingestion of poisonous food as well as the contact with pathogens and other harmful agents. Previous research has shown that multisensory presentation of olfactory and visual information may strengthen the processing of disgust-relevant information. However, it is not known whether these findings extend to dynamic facial stimuli that changes from neutral to emotionally expressive, or if individual differences in trait body odor disgust may influence the processing of disgust-related information. In this preregistered study, we tested whether a classification of dynamic facial expressions as happy or disgusted, and an emotional evaluation of these facial expressions, would be affected by individual differences in body odor disgust sensitivity, and by exposure to a sweat-like, negatively valenced odor (valeric acid), as compared with a soap-like, positively valenced odor (lilac essence) or a no-odor control. Using Bayesian hypothesis testing, we found evidence that odors do not affect recognition of emotion in dynamic faces even when body odor disgust sensitivity was used as moderator. However, an exploratory analysis suggested that an unpleasant odor context may cause faster RTs for faces, independent of their emotional expression. Our results further our understanding of the scope and limits of odor effects on facial perception affect and suggest further studies should focus on reproducibility, specifying experimental circumstances where odor effects on facial expressions may be present versus absent.

  10. Cross-cultural color-odor associations.

    Directory of Open Access Journals (Sweden)

    Carmel A Levitan

    Full Text Available Colors and odors are associated; for instance, people typically match the smell of strawberries to the color pink or red. These associations are forms of crossmodal correspondences. Recently, there has been discussion about the extent to which these correspondences arise for structural reasons (i.e., an inherent mapping between color and odor, statistical reasons (i.e., covariance in experience, and/or semantically-mediated reasons (i.e., stemming from language. The present study probed this question by testing color-odor correspondences in 6 different cultural groups (Dutch, Netherlands-residing-Chinese, German, Malay, Malaysian-Chinese, and US residents, using the same set of 14 odors and asking participants to make congruent and incongruent color choices for each odor. We found consistent patterns in color choices for each odor within each culture, showing that participants were making non-random color-odor matches. We used representational dissimilarity analysis to probe for variations in the patterns of color-odor associations across cultures; we found that US and German participants had the most similar patterns of associations, followed by German and Malay participants. The largest group differences were between Malay and Netherlands-resident Chinese participants and between Dutch and Malaysian-Chinese participants. We conclude that culture plays a role in color-odor crossmodal associations, which likely arise, at least in part, through experience.

  11. Cross-Cultural Color-Odor Associations

    Science.gov (United States)

    Levitan, Carmel A.; Ren, Jiana; Woods, Andy T.; Boesveldt, Sanne; Chan, Jason S.; McKenzie, Kirsten J.; Dodson, Michael; Levin, Jai A.; Leong, Christine X. R.; van den Bosch, Jasper J. F.

    2014-01-01

    Colors and odors are associated; for instance, people typically match the smell of strawberries to the color pink or red. These associations are forms of crossmodal correspondences. Recently, there has been discussion about the extent to which these correspondences arise for structural reasons (i.e., an inherent mapping between color and odor), statistical reasons (i.e., covariance in experience), and/or semantically-mediated reasons (i.e., stemming from language). The present study probed this question by testing color-odor correspondences in 6 different cultural groups (Dutch, Netherlands-residing-Chinese, German, Malay, Malaysian-Chinese, and US residents), using the same set of 14 odors and asking participants to make congruent and incongruent color choices for each odor. We found consistent patterns in color choices for each odor within each culture, showing that participants were making non-random color-odor matches. We used representational dissimilarity analysis to probe for variations in the patterns of color-odor associations across cultures; we found that US and German participants had the most similar patterns of associations, followed by German and Malay participants. The largest group differences were between Malay and Netherlands-resident Chinese participants and between Dutch and Malaysian-Chinese participants. We conclude that culture plays a role in color-odor crossmodal associations, which likely arise, at least in part, through experience. PMID:25007343

  12. Assessment of odor activity value coefficient and odor contribution based on binary interaction effects in waste disposal plant

    Science.gov (United States)

    Wu, Chuandong; Liu, Jiemin; Yan, Luchun; Chen, Haiying; Shao, Huiqi; Meng, Tian

    2015-02-01

    Odor activity value (OAV) has been widely used for the assessment of odor pollution from various sources. However, little attention has been paid to the extreme OAV variation and potential inaccuracies of odor contribution assessment caused by odor interaction effects. The objective of this study is to assess the odor interaction effect for precise assessment of odor contribution. In this paper, samples were collected from a food waste disposal plant, and analyzed by instrumental and olfactory method to conclude odorants' occurrence and OAV. Then odor activity value coefficient (γ) was first proposed to evaluate the type and the level of binary interaction effects based on determination of OAV variation. By multiplying OAV and γ, odor activity factor (OAF) was used to reflect the real OAV. Correlation between the sum of OAF and odor concentration reached 80.0 ± 5.7%, which was 10 times higher than the sum of OAV used before. Results showed that hydrogen sulfide contributed most (annual average 66.4 ± 15.8%) to odor pollution in the waste disposal plant. However, as odor intensity of samples in summer rising, odor contribution of trimethylamine increased to 48.3 ± 3.7% by the strong synergistic interaction effect, while odor contribution of phenol decreased to 0.1 ± 0.02% for the increasing antagonistic interaction effect.

  13. Predicting the response of olfactory sensory neurons to odor mixtures from single odor response

    OpenAIRE

    Marasco, Addolorata; De Paris, Alessandro; Migliore, Michele

    2016-01-01

    The response of olfactory receptor neurons to odor mixtures is not well understood. Here, using experimental constraints, we investigate the mathematical structure of the odor response space and its consequences. The analysis suggests that the odor response space is 3-dimensional, and predicts that the dose-response curve of an odor receptor can be obtained, in most cases, from three primary components with specific properties. This opens the way to an objective procedure to obtain specific o...

  14. Application of two-stage biofilter system for the removal of odorous compounds.

    Science.gov (United States)

    Jeong, Gwi-Taek; Park, Don-Hee; Lee, Gwang-Yeon; Cha, Jin-Myeong

    2006-01-01

    Biofiltration is a biological process which is considered to be one of the more successful examples of biotechnological applications to environmental engineering, and is most commonly used in the removal of odoriferous compounds. In this study, we have attempted to assess the efficiency with which both single and complex odoriferous compounds could be removed, using one- or two-stage biofiltration systems. The tested single odor gases, limonene, alpha-pinene, and iso-butyl alcohol, were separately evaluated in the biofilters. Both limonene and alpha-pinene were removed by 90% or more EC (elimination capacity), 364 g/m3/h and 321 g/m3/h, respectively, at an input concentration of 50 ppm and a retention time of 30 s. The iso-butyl alcohol was maintained with an effective removal yield of more than 90% (EC 375 g/m3/h) at an input concentration of 100 ppm. The complex gas removal scheme was applied with a 200 ppm inlet concentration of ethanol, 70 ppm of acetaldehyde, and 70 ppm of toluene with residence time of 45 s in a one- or two-stage biofiltration system. The removal yield of toluene was determined to be lower than that of the other gases in the one-stage biofilter. Otherwise, the complex gases were sufficiently eliminated by the two-stage biofiltration system.

  15. Investigation of indoor chemical pollutants and perceived odor in an area with complaints of unpleasant odors

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Chiung-Yu.; Wu, Tzong-Jer [Graduate Institute of Occupational Safety and Health, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Kaohsiung 807 (China); Lan, Cheng-Hang [Department of Occupational Safety and Health, Chung-Hwa University of Medical Technology, Tai-Nan County 717 (China)

    2009-10-15

    An uncomfortable smell was reported by employees of an IT office (information technological office) in a medical center. This problem started two years ago when the office was refurbished. The objectives of this study are to characterize the indoor air quality of this complaint area in terms of chemical pollutants and odor characteristics, and identify possible sources of this foul smell. Carbonyl chemicals and volatile organic compounds (VOCs) were investigated in this study, since these two groups are associated with odors and health effects. Additionally, the odor was evaluated by odor assessors (non-smokers) who recorded odor characters that appeared in offices. By comparing chemical measurements between complaint and non-complaint areas, calculating odor indices, and correlating odor and chemical measurements, we got results showing that a higher correlation coefficient is found between odor presence frequencies and VOC concentrations. Further investigating found nonanal and decanal are possible chemicals for malodors. The concentration levels of these two chemicals in the complaint area are higher than those in the non-complaint areas and exceeding odor thresholds. Possible sources of these long-chain aldehydes are formed during the oxidation degradations of fatty acids like linoleic acid, linolenic acid and oleic acid which are ingredients for many building products like linoleum and surface coating. In order to mitigate this malodor problem, extra and effective ventilation flow rate should be provided to reduce the concentrations of odorous chemicals and the precursors for these odorous chemicals. (author)

  16. Odor memories regulate olfactory receptor expression in the sensory periphery.

    Science.gov (United States)

    Claudianos, Charles; Lim, Julianne; Young, Melanie; Yan, Shanzhi; Cristino, Alexandre S; Newcomb, Richard D; Gunasekaran, Nivetha; Reinhard, Judith

    2014-05-01

    Odor learning induces structural and functional modifications throughout the olfactory system, but it is currently unknown whether this plasticity extends to the olfactory receptors (Or) in the sensory periphery. Here, we demonstrate that odor learning induces plasticity in olfactory receptor expression in the honeybee, Apis mellifera. Using quantitative RT-PCR analysis, we show that six putative floral scent receptors were differentially expressed in the bee antennae depending on the scent environment that the bees experienced. Or151, which we characterized using an in vitro cell expression system as a broadly tuned receptor binding floral odorants such as linalool, and Or11, the specific receptor for the queen pheromone 9-oxo-decenoic acid, were significantly down-regulated after honeybees were conditioned with the respective odorants in an olfactory learning paradigm. Electroantennogram recordings showed that the neural response of the antenna was similarly reduced after odor learning. Long-term odor memory was essential for inducing these changes, suggesting that the molecular mechanisms involved in olfactory memory also regulate olfactory receptor expression. Our study demonstrates for the first time that olfactory receptor expression is experience-dependent and modulated by scent conditioning, providing novel insight into how molecular regulation at the periphery contributes to plasticity in the olfactory system. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  17. Behavioral responses to mammalian blood odor and a blood odor component in four species of large carnivores.

    Directory of Open Access Journals (Sweden)

    Sara Nilsson

    Full Text Available Only little is known about whether single volatile compounds are as efficient in eliciting behavioral responses in animals as the whole complex mixture of a behaviorally relevant odor. Recent studies analysing the composition of volatiles in mammalian blood, an important prey-associated odor stimulus for predators, found the odorant trans-4,5-epoxy-(E-2-decenal to evoke a typical "metallic, blood-like" odor quality in humans. We therefore assessed the behavior of captive Asian wild dogs (Cuon alpinus, African wild dogs (Lycaon pictus, South American bush dogs (Speothos venaticus, and Siberian tigers (Panthera tigris altaica when presented with wooden logs that were impregnated either with mammalian blood or with the blood odor component trans-4,5-epoxy-(E-2-decenal, and compared it to their behavior towards a fruity odor (iso-pentyl acetate and a near-odorless solvent (diethyl phthalate as control. We found that all four species displayed significantly more interactions with the odorized wooden logs such as sniffing, licking, biting, pawing, and toying, when they were impregnated with the two prey-associated odors compared to the two non-prey-associated odors. Most importantly, no significant differences were found in the number of interactions with the wooden logs impregnated with mammalian blood and the blood odor component in any of the four species. Only one of the four species, the South American bush dogs, displayed a significant decrease in the number of interactions with the odorized logs across the five sessions performed per odor stimulus. Taken together, the results demonstrate that a single blood odor component can be as efficient in eliciting behavioral responses in large carnivores as the odor of real blood, suggesting that trans-4,5-epoxy-(E-2-decenal may be perceived by predators as a "character impact compound" of mammalian blood odor. Further, the results suggest that odorized wooden logs are a suitable manner of environmental

  18. The role of the ventral dentate gyrus in olfactory pattern separation.

    Science.gov (United States)

    Weeden, Christy S S; Hu, Nathan J; Ho, Liana U N; Kesner, Raymond P

    2014-05-01

    Dorsoventral lesion studies of the hippocampus have indicated that the dorsal axis of the hippocampus is important for spatial processing and the ventral axis of the hippocampus is important for olfactory learning and memory and anxiety. There is some evidence to suggest that the ventral CA3 and ventral CA1 conduct parallel processes for pattern completion and temporal processing, respectively. Studies have indicated that the dorsal dentate gyrus (DG) is importantly involved in processes reflecting underlying pattern separation activity for spatial information. However, the ventral DG is less understood. The current study investigated the less-understood role of the ventral DG in olfactory pattern separation. A series of odor stimuli that varied on only one level, number of carbon chains (methyl groups), was used in a matching-to-sample paradigm in order to investigate ventral DG involvement in working memory for similar and less similar odors. Rats with ventral DG lesions were impaired at delays of 60 sec, but not at delays of 15 sec. A memory-based pattern separation effect was observed performance was poorest with only one carbon chain separation between trial odors and was highest for trials with four separations. The present study indicates that the ventral DG plays an important role in olfactory learning and memory processes for highly similar odors. The results also indicate a role for the ventral DG in pattern separation for odor information, which may have further implications for parallel processing across the dorsoventral axis for the DG in spatial (dorsal) and olfactory (ventral) pattern separation. Copyright © 2014 Wiley Periodicals, Inc.

  19. Improved quantification of livestock associated odorous volatile organic compounds in a standard flow-through system using solid-phase microextraction and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Yang, Xiuyan; Zhu, Wenda; Koziel, Jacek A; Cai, Lingshuang; Jenks, William S; Laor, Yael; Leeuwen, J Hans van; Hoff, Steven J

    2015-10-02

    Aerial emissions of odorous volatile organic compounds (VOCs) are an important nuisance factor from livestock production systems. Reliable air sampling and analysis methods are needed to develop and test odor mitigation technologies. Quantification of VOCs responsible for livestock odor remains an analytical challenge due to physicochemical properties of VOCs and the requirement for low detection thresholds. A new air sampling and analysis method was developed for testing of odor/VOCs mitigation in simulated livestock emissions system. A flow-through standard gas generating system simulating odorous VOCs in livestock barn emissions was built on laboratory scale and tested to continuously generate ten odorous VOCs commonly defining livestock odor. Standard VOCs included sulfur VOCs (S-VOCs), volatile fatty acids (VFAs), and p-cresol. Solid-phase microextraction (SPME) was optimized for sampling of diluted odorous gas mixtures in the moving air followed by gas chromatography-mass spectrometry (GC-MS) analysis. CAR/PDMS 85μm fiber was shown to have the best sensitivity for the target odorous VOCs. A practical 5-min sampling time was selected to ensure optimal extraction of VFAs and p-cresol, as well as minimum displacement of S-VOCs. Method detection limits ranged from 0.39 to 2.64ppbv for S-VOCs, 0.23 to 0.77ppbv for VFAs, and 0.31ppbv for p-cresol. The method developed was applied to quantify VOCs and odorous VOC mitigation with UV light treatment. The measured concentrations ranged from 20.1 to 815ppbv for S-VOCs, 10.3 to 315ppbv for VFAs, and 4.73 to 417ppbv for p-cresol. Relative standard deviations between replicates ranged from 0.67% to 12.9%, 0.50% to 11.4%, 0.83% to 5.14% for S-VOCs, VFAs, and p-cresol, respectively. This research shows that a simple manual SPME sampler could be used successfully for quantification of important classes of odorous VOCs at concentrations relevant for real aerial emissions from livestock operations. Copyright © 2015 Elsevier B

  20. Learning-dependent and -independent enhancement of mitral/tufted cell glomerular odor responses following olfactory fear conditioning in awake mice.

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    Ross, Jordan M; Fletcher, Max L

    2018-04-18

    Associative fear learning produces fear toward the conditioned stimulus (CS) and often generalization, the expansion of fear from the CS to similar, unlearned stimuli. However, how fear learning affects early sensory processing of learned and unlearned stimuli in relation to behavioral fear responses to these stimuli remains unclear. We subjected male and female mice expressing the fluorescent calcium indicator GCaMP3 in olfactory bulb mitral and tufted cells to a classical olfactory fear conditioning paradigm. We then used awake, in vivo calcium imaging to quantify learning-induced changes in glomerular odor responses, which constitute the first site of olfactory processing in the brain. The results demonstrate that odor-shock pairing non-specifically enhances glomerular odor representations in a learning-dependent manner and increases representational similarity between the CS and non-conditioned odors, potentially priming the system towards generalization of learned fear. Additionally, CS-specific glomerular enhancements remain even when associative learning is blocked, suggesting two separate mechanisms lead to enhanced glomerular responses following odor-shock pairings. SIGNIFICANCE STATEMENT In the olfactory bulb (OB), odors are uniquely coded in a spatial map that represents odor identity, making the OB a unique model system for investigating how learned fear alters sensory processing. Classical fear conditioning causes fear of the conditioned stimulus (CS) and of neutral stimuli, known as generalization. Combining fear conditioning with fluorescent calcium imaging of OB glomeruli, we found enhanced glomerular responses of the CS as well as neutral stimuli in awake mice, which mirrors fear generalization. We report that CS and neutral stimuli enhancements are, respectively, learning- independent and learning-dependent. Together, these results reveal distinct mechanisms leading to enhanced OB processing of fear-inducing stimuli and provide important

  1. A pleasant familiar odor influences perceived stress and peripheral nervous system activity during normal aging

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    Pauline eJoussain

    2014-02-01

    Full Text Available Effects of smells on stress have been demonstrated in animals and humans, suggesting that inhaling certain odorants may counteract the negative effects of stress. Because stress plays a key role in cerebral aging, the present study set out to examine whether positive odor effects on perceived stress can be achieved in elderly individuals. To this end, two groups of aged individuals (n=36 women, aged from 55 to 65 years, were tested. The first group was exposed for 5 days to a pleasant and, by end of exposure, familiar odor (exposure odor, whereas the other was exposed to a non-scented control stimulus. Stress and mood states were assessed before and after the 5-day odor exposure period. Psychophysiological markers were also assessed at the end of exposure, in response to the exposure odor and to a new odor. Results revealed that stress on this second exposure was decreased and zygomatic EMG activity was increased specifically in the group previously exposed to the odor (p< 0.05. Taken as a whole, these findings offer a new look at the relationship between perceived stress, olfaction and normal aging, opening up new research perspectives on the effect of olfaction on quality of life and well-being in aged individuals.

  2. Neuroendocrine changes upon exposure to predator odors.

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    Hegab, Ibrahim M; Wei, Wanhong

    2014-05-28

    Predator odors are non-intrusive and naturalistic stressors of high ethological relevance in animals. Upon exposure to a predator or its associated cues, robust physiological and molecular anti-predator defensive strategies are elicited thereby allowing prey species to recognize, avoid and defend against a possible predation threat. In this review, we will discuss the nature of neuroendocrine stress responses upon exposure to predator odors. Predator odors can have a profound effect on the endocrine system, including activation of the hypothalamic-pituitary-adrenal axis, and induction of stress hormones such as corticosterone and adrenocorticotropic hormone. On a neural level, short-term exposure to predator odors leads to induction of the c-fos gene, while induction of ΔFosB in a different brain region is detected under chronic predation stress. Future research should aim to elucidate the relationships between neuroendocrine and behavioral outputs to gage the different levels of anti-predator responses in prey species. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Odor and odorous chemical emissions from animal buildings: part 1 - project overview, collection methods, and quality control

    Science.gov (United States)

    Livestock facilities have historically generated public concerns due to their emissions of odorous air and various chemical pollutants. Odor emission factors and identification of principal odorous chemicals are needed to better understand the problem. Applications of odor emission factors include i...

  4. Altered olfactory processing of stress-related body odors and artificial odors in patients with panic disorder.

    Science.gov (United States)

    Wintermann, Gloria-Beatrice; Donix, Markus; Joraschky, Peter; Gerber, Johannes; Petrowski, Katja

    2013-01-01

    Patients with Panic Disorder (PD) direct their attention towards potential threat, followed by panic attacks, and increased sweat production. Onés own anxiety sweat odor influences the attentional focus, and discrimination of threat or non-threat. Since olfactory projection areas overlap with neuronal areas of a panic-specific fear network, the present study investigated the neuronal processing of odors in general and of stress-related sweat odors in particular in patients with PD. A sample of 13 patients with PD with/ without agoraphobia and 13 age- and gender-matched healthy controls underwent an fMRI investigation during olfactory stimulation with their stress-related sweat odors (TSST, ergometry) as well as artificial odors (peach, artificial sweat) as non-fearful non-body odors. The two groups did not differ with respect to their olfactory identification ability. Independent of the kind of odor, the patients with PD showed activations in fronto-cortical areas in contrast to the healthy controls who showed activations in olfaction-related areas such as the amygdalae and the hippocampus. For artificial odors, the patients with PD showed a decreased neuronal activation of the thalamus, the posterior cingulate cortex and the anterior cingulate cortex. Under the presentation of sweat odor caused by ergometric exercise, the patients with PD showed an increased activation in the superior temporal gyrus, the supramarginal gyrus, and the cingulate cortex which was positively correlated with the severity of the psychopathology. For the sweat odor from the anxiety condition, the patients with PD showed an increased activation in the gyrus frontalis inferior, which was positively correlated with the severity of the psychopathology. The results suggest altered neuronal processing of olfactory stimuli in PD. Both artificial odors and stress-related body odors activate specific parts of a fear-network which is associated with an increased severity of the psychopathology.

  5. Altered olfactory processing of stress-related body odors and artificial odors in patients with panic disorder.

    Directory of Open Access Journals (Sweden)

    Gloria-Beatrice Wintermann

    Full Text Available Patients with Panic Disorder (PD direct their attention towards potential threat, followed by panic attacks, and increased sweat production. Onés own anxiety sweat odor influences the attentional focus, and discrimination of threat or non-threat. Since olfactory projection areas overlap with neuronal areas of a panic-specific fear network, the present study investigated the neuronal processing of odors in general and of stress-related sweat odors in particular in patients with PD.A sample of 13 patients with PD with/ without agoraphobia and 13 age- and gender-matched healthy controls underwent an fMRI investigation during olfactory stimulation with their stress-related sweat odors (TSST, ergometry as well as artificial odors (peach, artificial sweat as non-fearful non-body odors.The two groups did not differ with respect to their olfactory identification ability. Independent of the kind of odor, the patients with PD showed activations in fronto-cortical areas in contrast to the healthy controls who showed activations in olfaction-related areas such as the amygdalae and the hippocampus. For artificial odors, the patients with PD showed a decreased neuronal activation of the thalamus, the posterior cingulate cortex and the anterior cingulate cortex. Under the presentation of sweat odor caused by ergometric exercise, the patients with PD showed an increased activation in the superior temporal gyrus, the supramarginal gyrus, and the cingulate cortex which was positively correlated with the severity of the psychopathology. For the sweat odor from the anxiety condition, the patients with PD showed an increased activation in the gyrus frontalis inferior, which was positively correlated with the severity of the psychopathology.The results suggest altered neuronal processing of olfactory stimuli in PD. Both artificial odors and stress-related body odors activate specific parts of a fear-network which is associated with an increased severity of the

  6. Identification of agonists for a group of human odorant receptors

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    Daniela eGonzalez-Kristeller

    2015-03-01

    Full Text Available Olfaction plays a critical role in several aspects of the human life. Odorants are detected by hundreds of odorant receptors (ORs which belong to the superfamily of G protein-coupled receptors. These receptors are expressed in the olfactory sensory neurons of the nose. The information provided by the activation of different combinations of ORs in the nose is transmitted to the brain, leading to odorant perception and emotional and behavioral responses. There are ~400 intact human ORs, and to date only a small percentage of these receptors (~10% have known agonists. The determination of the specificity of the human ORs will contribute to a better understanding of how odorants are discriminated by the olfactory system. In this work, we aimed to identify human specific ORs, that is, ORs that are present in humans but absent from other species, and their corresponding agonists. To do this, we first selected 22 OR gene sequences from the human genome with no counterparts in the mouse, rat or dog genomes. Then we used a heterologous expression system to screen a subset of these human ORs against a panel of odorants of biological relevance, including foodborne aroma volatiles. We found that different types of odorants are able to activate some of these previously uncharacterized human ORs.

  7. Combinatorial effects of odorants on mouse behavior

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    Saraiva, Luis R.; Kondoh, Kunio; Ye, Xiaolan; Yoon, Kyoung-hye; Hernandez, Marcus; Buck, Linda B.

    2016-01-01

    The mechanisms by which odors induce instinctive behaviors are largely unknown. Odor detection in the mouse nose is mediated by >1, 000 different odorant receptors (ORs) and trace amine-associated receptors (TAARs). Odor perceptions are encoded combinatorially by ORs and can be altered by slight changes in the combination of activated receptors. However, the stereotyped nature of instinctive odor responses suggests the involvement of specific receptors and genetically programmed neural circuits relatively immune to extraneous odor stimuli and receptor inputs. Here, we report that, contrary to expectation, innate odor-induced behaviors can be context-dependent. First, different ligands for a given TAAR can vary in behavioral effect. Second, when combined, some attractive and aversive odorants neutralize one another’s behavioral effects. Both a TAAR ligand and a common odorant block aversion to a predator odor, indicating that this ability is not unique to TAARs and can extend to an aversive response of potential importance to survival. In vitro testing of single receptors with binary odorant mixtures indicates that behavioral blocking can occur without receptor antagonism in the nose. Moreover, genetic ablation of a single receptor prevents its cognate ligand from blocking predator odor aversion, indicating that the blocking requires sensory input from the receptor. Together, these findings indicate that innate odor-induced behaviors can depend on context, that signals from a single receptor can block innate odor aversion, and that instinctive behavioral responses to odors can be modulated by interactions in the brain among signals derived from different receptors. PMID:27208093

  8. Red junglefowl have individual body odors.

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    Karlsson, Anna-Carin; Jensen, Per; Elgland, Mathias; Laur, Katriann; Fyrner, Timmy; Konradsson, Peter; Laska, Matthias

    2010-05-01

    Olfaction may play an important role in regulating bird behavior, and has been suggested to be involved in feather-pecking. We investigated possible differences in the body odors of red junglefowl females by using an automated olfactometer which assessed the ability of trained mice to discriminate between the odors of uropygial gland secretions (the main carrier of potential individual odors in chickens) of six feather-pecked and six non-pecked birds. All mice were clearly able to discriminate between all individual red junglefowl odors, showing that each bird has an individual body odor. We analyzed whether it was more difficult to discriminate between the odors of two feather-pecked, or two non-pecked birds, than it was to discriminate between the odors of two randomly selected birds. This was not the case, suggesting that feather-pecked birds did not share a common odor signature. Analyses using gas chromatography and mass spectrometry showed that the composition of aliphatic carboxylic acids in uropygial gland secretions differed consistently between individuals. However, chemical composition did not vary according to feather-pecking status. We conclude that red junglefowl have individual body odors which appear to be largely based on differences in the relative abundance of aliphatic carboxylic acids, but there is no evidence of systematic differences between the body odors of pecked and non-pecked birds.

  9. An olfactory cocktail party: figure-ground segregation of odorants in rodents.

    Science.gov (United States)

    Rokni, Dan; Hemmelder, Vivian; Kapoor, Vikrant; Murthy, Venkatesh N

    2014-09-01

    In odorant-rich environments, animals must be able to detect specific odorants of interest against variable backgrounds. However, studies have found that both humans and rodents are poor at analyzing the components of odorant mixtures, suggesting that olfaction is a synthetic sense in which mixtures are perceived holistically. We found that mice could be easily trained to detect target odorants embedded in unpredictable and variable mixtures. To relate the behavioral performance to neural representation, we imaged the responses of olfactory bulb glomeruli to individual odors in mice expressing the Ca(2+) indicator GCaMP3 in olfactory receptor neurons. The difficulty of segregating the target from the background depended strongly on the extent of overlap between the glomerular responses to target and background odors. Our study indicates that the olfactory system has powerful analytic abilities that are constrained by the limits of combinatorial neural representation of odorants at the level of the olfactory receptors.

  10. Brain-immune interaction accompanying odor-evoked autobiographic memory.

    Science.gov (United States)

    Matsunaga, Masahiro; Bai, Yu; Yamakawa, Kaori; Toyama, Asako; Kashiwagi, Mitsuyoshi; Fukuda, Kazuyuki; Oshida, Akiko; Sanada, Kazue; Fukuyama, Seisuke; Shinoda, Jun; Yamada, Jitsuhiro; Sadato, Norihiro; Ohira, Hideki

    2013-01-01

    The phenomenon in which a certain smell evokes a specific memory is known as the Proust phenomenon. Odor-evoked autobiographic memories are more emotional than those elicited by other sensory stimuli. The results of our previous study indicated that odor-evoked autobiographic memory accompanied by positive emotions has remarkable effects on various psychological and physiological activities, including the secretion of cytokines, which are immune-signaling molecules that modulate systemic inflammation. In this study, we aimed to clarify the neural substrates associated with the interaction between odor-evoked autobiographic memory and peripheral circulating cytokines. We recruited healthy male and female volunteers and investigated the association between brain responses and the concentration of several cytokines in the plasma by using positron emission tomography (PET) recordings when an autographic memory was evoked in participants by asking them to smell an odor that was nostalgic to them. Participants experienced positive emotions and autobiographic memories when nostalgic odors were presented to them. The levels of peripheral proinflammatory cytokines, such as the tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), were significantly reduced after experiencing odor-evoked autobiographic memory. Subtraction analysis of PET images indicated that the medial orbitofrontal cortex (mOFC) and precuneus/posterior cingulate cortex (PCC) were significantly activated during experiences of odor-evoked autobiographic memory. Furthermore, a correlation analysis indicated that activities of the mOFC and precuneus/PCC were negatively correlated with IFN-γ concentration. These results indicate that the neural networks including the precuneus/PCC and mOFC might regulate the secretion of peripheral proinflammatory cytokines during the experience of odor-evoked autobiographic memories accompanied with positive emotions.

  11. Brain–Immune Interaction Accompanying Odor-Evoked Autobiographic Memory

    Science.gov (United States)

    Matsunaga, Masahiro; Bai, Yu; Yamakawa, Kaori; Toyama, Asako; Kashiwagi, Mitsuyoshi; Fukuda, Kazuyuki; Oshida, Akiko; Sanada, Kazue; Fukuyama, Seisuke; Shinoda, Jun; Yamada, Jitsuhiro; Sadato, Norihiro; Ohira, Hideki

    2013-01-01

    The phenomenon in which a certain smell evokes a specific memory is known as the Proust phenomenon. Odor-evoked autobiographic memories are more emotional than those elicited by other sensory stimuli. The results of our previous study indicated that odor-evoked autobiographic memory accompanied by positive emotions has remarkable effects on various psychological and physiological activities, including the secretion of cytokines, which are immune-signaling molecules that modulate systemic inflammation. In this study, we aimed to clarify the neural substrates associated with the interaction between odor-evoked autobiographic memory and peripheral circulating cytokines. We recruited healthy male and female volunteers and investigated the association between brain responses and the concentration of several cytokines in the plasma by using positron emission tomography (PET) recordings when an autographic memory was evoked in participants by asking them to smell an odor that was nostalgic to them. Participants experienced positive emotions and autobiographic memories when nostalgic odors were presented to them. The levels of peripheral proinflammatory cytokines, such as the tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), were significantly reduced after experiencing odor-evoked autobiographic memory. Subtraction analysis of PET images indicated that the medial orbitofrontal cortex (mOFC) and precuneus/posterior cingulate cortex (PCC) were significantly activated during experiences of odor-evoked autobiographic memory. Furthermore, a correlation analysis indicated that activities of the mOFC and precuneus/PCC were negatively correlated with IFN-γ concentration. These results indicate that the neural networks including the precuneus/PCC and mOFC might regulate the secretion of peripheral proinflammatory cytokines during the experience of odor-evoked autobiographic memories accompanied with positive emotions. PMID:23977312

  12. Brain-immune interaction accompanying odor-evoked autobiographic memory.

    Directory of Open Access Journals (Sweden)

    Masahiro Matsunaga

    Full Text Available The phenomenon in which a certain smell evokes a specific memory is known as the Proust phenomenon. Odor-evoked autobiographic memories are more emotional than those elicited by other sensory stimuli. The results of our previous study indicated that odor-evoked autobiographic memory accompanied by positive emotions has remarkable effects on various psychological and physiological activities, including the secretion of cytokines, which are immune-signaling molecules that modulate systemic inflammation. In this study, we aimed to clarify the neural substrates associated with the interaction between odor-evoked autobiographic memory and peripheral circulating cytokines. We recruited healthy male and female volunteers and investigated the association between brain responses and the concentration of several cytokines in the plasma by using positron emission tomography (PET recordings when an autographic memory was evoked in participants by asking them to smell an odor that was nostalgic to them. Participants experienced positive emotions and autobiographic memories when nostalgic odors were presented to them. The levels of peripheral proinflammatory cytokines, such as the tumor necrosis factor-α (TNF-α and interferon-γ (IFN-γ, were significantly reduced after experiencing odor-evoked autobiographic memory. Subtraction analysis of PET images indicated that the medial orbitofrontal cortex (mOFC and precuneus/posterior cingulate cortex (PCC were significantly activated during experiences of odor-evoked autobiographic memory. Furthermore, a correlation analysis indicated that activities of the mOFC and precuneus/PCC were negatively correlated with IFN-γ concentration. These results indicate that the neural networks including the precuneus/PCC and mOFC might regulate the secretion of peripheral proinflammatory cytokines during the experience of odor-evoked autobiographic memories accompanied with positive emotions.

  13. Ontogeny of Odor-LiCl vs. Odor-Shock Learning: Similar Behaviors but Divergent Ages of Functional Amygdala Emergence

    Science.gov (United States)

    Raineki, Charlis; Shionoya, Kiseko; Sander, Kristin; Sullivan, Regina M.

    2009-01-01

    Both odor-preference and odor-aversion learning occur in perinatal pups before the maturation of brain structures that support this learning in adults. To characterize the development of odor learning, we compared three learning paradigms: (1) odor-LiCl (0.3M; 1% body weight, ip) and (2) odor-1.2-mA shock (hindlimb, 1sec)--both of which…

  14. Nanocellulose-Zeolite Composite Films for Odor Elimination.

    Science.gov (United States)

    Keshavarzi, Neda; Mashayekhy Rad, Farshid; Mace, Amber; Ansari, Farhan; Akhtar, Farid; Nilsson, Ulrika; Berglund, Lars; Bergström, Lennart

    2015-07-08

    Free standing and strong odor-removing composite films of cellulose nanofibrils (CNF) with a high content of nanoporous zeolite adsorbents have been colloidally processed. Thermogravimetric desorption analysis (TGA) and infrared spectroscopy combined with computational simulations showed that commercially available silicalite-1 and ZSM-5 have a high affinity and uptake of volatile odors like ethanethiol and propanethiol, also in the presence of water. The simulations showed that propanethiol has a higher affinity, up to 16%, to the two zeolites compared with ethanethiol. Highly flexible and strong free-standing zeolite-CNF films with an adsorbent loading of 89 w/w% have been produced by Ca-induced gelation and vacuum filtration. The CNF-network controls the strength of the composite films and 100 μm thick zeolite-CNF films with a CNF content of less than 10 vol % displayed a tensile strength approaching 10 MPa. Headspace solid phase microextraction (SPME) coupled to gas chromatography-mass spectroscopy (GC/MS) analysis showed that the CNF-zeolite films can eliminate the volatile thiol-based odors to concentrations below the detection ability of the human olfactory system. Odor removing zeolite-cellulose nanofibril films could enable improved transport and storage of fruits and vegetables rich in odors, for example, onion and the tasty but foul-smelling South-East Asian Durian fruit.

  15. Co-regulation of a large and rapidly evolving repertoire of odorant receptor genes

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    Lane Robert P

    2007-09-01

    Full Text Available Abstract The olfactory system meets niche- and species-specific demands by an accelerated evolution of its odorant receptor repertoires. In this review, we describe evolutionary processes that have shaped olfactory and vomeronasal receptor gene families in vertebrate genomes. We emphasize three important periods in the evolution of the olfactory system evident by comparative genomics: the adaptation to land in amphibian ancestors, the decline of olfaction in primates, and the delineation of putative pheromone receptors concurrent with rodent speciation. The rapid evolution of odorant receptor genes, the sheer size of the repertoire, as well as their wide distribution in the genome, presents a developmental challenge: how are these ever-changing odorant receptor repertoires coordinated within the olfactory system? A central organizing principle in olfaction is the specialization of sensory neurons resulting from each sensory neuron expressing only ~one odorant receptor allele. In this review, we also discuss this mutually exclusive expression of odorant receptor genes. We have considered several models to account for co-regulation of odorant receptor repertoires, as well as discussed a new hypothesis that invokes important epigenetic properties of the system.

  16. Understanding odor information segregation in the olfactory bulb by means of mitral and tufted cells.

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    Davide Polese

    Full Text Available Odor identification is one of the main tasks of the olfactory system. It is performed almost independently from the concentration of the odor providing a robust recognition. This capacity to ignore concentration information does not preclude the olfactory system from estimating concentration itself. Significant experimental evidence has indicated that the olfactory system is able to infer simultaneously odor identity and intensity. However, it is still unclear at what level or levels of the olfactory pathway this segregation of information occurs. In this work, we study whether this odor information segregation is performed at the input stage of the olfactory bulb: the glomerular layer. To this end, we built a detailed neural model of the glomerular layer based on its known anatomical connections and conducted two simulated odor experiments. In the first experiment, the model was exposed to an odor stimulus dataset composed of six different odorants, each one dosed at six different concentrations. In the second experiment, we conducted an odor morphing experiment where a sequence of binary mixtures going from one odor to another through intermediate mixtures was presented to the model. The results of the experiments were visualized using principal components analysis and analyzed with hierarchical clustering to unveil the structure of the high-dimensional output space. Additionally, Fisher's discriminant ratio and Pearson's correlation coefficient were used to quantify odor identity and odor concentration information respectively. Our results showed that the architecture of the glomerular layer was able to mediate the segregation of odor information obtaining output spiking sequences of the principal neurons, namely the mitral and external tufted cells, strongly correlated with odor identity and concentration, respectively. An important conclusion is also that the morphological difference between the principal neurons is not key to achieve odor

  17. Regulation of cutaneous allergic reaction by odorant inhalation.

    Science.gov (United States)

    Hosoi, J; Tsuchiya, T

    2000-03-01

    Olfactory stimuli modulate emotional conditions and the whole body immune system. Effects of odorant inhalation on cutaneous immune reaction were examined. Contact hypersensitivity to 2,4, 6-trinitrochlorobenzene was elicited in C57BL/6 mice. The reaction was suppressed at both the induction and elicitation phases by exposure to an odorant, citralva. Topical application of citralva or lyral/lilial did not affect the reaction. The suppressive effect of citralva was more potent than that of another odorant, lyral/lilial. Citralva decreased the number of epidermal Langerhans cells, whereas lyral/lilial had a weak effect. Citralva but not lyral/lilial induced plasma corticosterone. Glucocorticoid receptor antagonist abrogated the suppressive effect of citralva on contact hypersensitivity. Serum interleukin-12 was downregulated by exposure to citralva or lyral/lilial. These data demonstrate that olfactory stimuli regulate the cutaneous immune system.

  18. Odorant responsiveness of embryonic mouse olfactory sensory neurons expressing the odorant receptors S1 or MOR23.

    Science.gov (United States)

    Lam, Rebecca S; Mombaerts, Peter

    2013-07-01

    The mammalian olfactory system has developed some functionality by the time of birth. There is behavioral and limited electrophysiological evidence for prenatal olfaction in various mammalian species. However, there have been no reports, in any mammalian species, of recordings from prenatal olfactory sensory neurons (OSNs) that express a given odorant receptor (OR) gene. Here we have performed patch-clamp recordings from mouse OSNs that express the OR gene S1 or MOR23, using the odorous ligands 2-phenylethyl alcohol or lyral, respectively. We found that, out of a combined total of 20 OSNs from embryos of these two strains at embryonic day (E)16.5 or later, all responded to a cognate odorous ligand. By contrast, none of six OSNs responded to the ligand at E14.5 or E15.5. The kinetics of the odorant-evoked electrophysiological responses of prenatal OSNs are similar to those of postnatal OSNs. The S1 and MOR23 glomeruli in the olfactory bulb are formed postnatally, but the axon terminals of OSNs expressing these OR genes may be synaptically active in the olfactory bulb at embryonic stages. The upper limit of the acquisition of odorant responsiveness for S1 and MOR23 OSNs at E16.5 is consistent with the developmental expression patterns of components of the olfactory signaling pathway. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  19. Identification of Odorant-Receptor Interactions by Global Mapping of the Human Odorome

    DEFF Research Database (Denmark)

    Audouze, Karine Marie Laure; Tromelin, Anne; Le Bon, Anne Marie

    2014-01-01

    The human olfactory system recognizes a broad spectrum of odorants using approximately 400 different olfactory receptors ( hORs). Although significant improvements of heterologous expression systems used to study interactions between ORs and odorant molecules have been made, screening the olfacto...

  20. Odor management in petroleum refining units; Gerenciamento de odores em refinaria de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Gutierres, Ricardo; Evangelho, Mauro Rocha; Moreira, Andrea Cristina de Castro Araujo [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES). P e D de Energia e Desenvolvimento Sustentavel (PDEDS)

    2004-07-01

    Odor emissions can cause serious annoyance in the neighbourhood of the emissions sources related to industrial processes and effluent and wastewater treatments. Jointly with the industrial control for reducing the odor, the emissions monitoring becomes convenient for identification and quantification of compounds responsible for the odors. To reach this objective, they are proposed analytical and olfactometric methodologies. The analytical procedures are based on the application of methods of sampling and analysis in gas chromatography-mass spectrometry, accepted for environmental agencies. The olfactometric methodology is based on the use of procedures that consider the subjective manner with that the odors are felt and evaluated by the people. This work describes as these methodologies can be applied in petroleum refining units. (author)

  1. Optimization of the Odor Microclimate

    Directory of Open Access Journals (Sweden)

    M. V. Jokl

    2002-01-01

    Full Text Available The odor microclimate is formed by gaseous airborne components perceived either as an unpleasant smell or as a pleasant smell. Smells enter the building interior partly from outdoors (exhaust fumes - flower fragrance and partly from indoors (building materials, smoking cigarettes - cosmetics, dishes. They affect the human organism through the olfactory center which is connected to the part of brain that is responsible for controlling people's emotions and sexual feelings: smells therefore participate to a high level in mood formation. Sweet smells have a positive impact on human feelings and on human performance. Criteria for odor microclimate appraisal are presented together with ways of improving the odor microclimate (by stopping odors from spreading within a building, ventilation, air filtration, odor removal by plants, deodorization, etc., including so-called AIR DESIGN.

  2. Olfactory tubercle stimulation alters odor preference behavior and recruits forebrain reward and motivational centers

    Directory of Open Access Journals (Sweden)

    Brynn J FitzGerald

    2014-03-01

    Full Text Available Rodents show robust behavioral responses to odors, including strong preferences or aversions for certain odors. The neural mechanisms underlying the effects of odors on these behaviors in animals are not well understood. Here, we provide an initial proof-of-concept study into the role of the olfactory tubercle (OT, a structure with known anatomical connectivity with both brain reward and olfactory structures, in regulating odor-motivated behaviors. We implanted c57bl/6 male mice with an ipsilateral bipolar electrode into the OT to administer electric current and thereby yield gross activation of the OT. We confirmed that electrical stimulation of the OT was rewarding, with mice frequently self-administering stimulation on a fixed ratio schedule. In a separate experiment, mice were presented with either fox urine or peanut odors in a three-chamber preference test. In absence of OT stimulation, significant preference for the peanut odor chamber was observed which was abolished in the presence of OT stimulation. Perhaps providing a foundation for this modulation in behavior, we found that OT stimulation significantly increased the number of c-Fos positive neurons in not only the OT, but also in forebrain structures essential to motivated behaviors, including the nucleus accumbens and lateral septum. The present results support the notion that the OT is integral to the display of motivated behavior and possesses the capacity to modulate odor hedonics either by directly altering odor processing or perhaps by indirect actions on brain reward and motivation structures.

  3. The Role of Odor-Evoked Memory in Psychological and Physiological Health.

    Science.gov (United States)

    Herz, Rachel S

    2016-07-19

    This article discusses the special features of odor-evoked memory and the current state-of-the-art in odor-evoked memory research to show how these unique experiences may be able to influence and benefit psychological and physiological health. A review of the literature leads to the conclusion that odors that evoke positive autobiographical memories have the potential to increase positive emotions, decrease negative mood states, disrupt cravings, and reduce physiological indices of stress, including systemic markers of inflammation. Olfactory perception factors and individual difference characteristics that would need to be considered in therapeutic applications of odor-evoked-memory are also discussed. This article illustrates how through the experimentally validated mechanisms of odor-associative learning and the privileged neuroanatomical relationship that exists between olfaction and the neural substrates of emotion, odors can be harnessed to induce emotional and physiological responses that can improve human health and wellbeing.

  4. The Role of Odor-Evoked Memory in Psychological and Physiological Health

    Directory of Open Access Journals (Sweden)

    Rachel S. Herz

    2016-07-01

    Full Text Available This article discusses the special features of odor-evoked memory and the current state-of-the-art in odor-evoked memory research to show how these unique experiences may be able to influence and benefit psychological and physiological health. A review of the literature leads to the conclusion that odors that evoke positive autobiographical memories have the potential to increase positive emotions, decrease negative mood states, disrupt cravings, and reduce physiological indices of stress, including systemic markers of inflammation. Olfactory perception factors and individual difference characteristics that would need to be considered in therapeutic applications of odor-evoked-memory are also discussed. This article illustrates how through the experimentally validated mechanisms of odor-associative learning and the privileged neuroanatomical relationship that exists between olfaction and the neural substrates of emotion, odors can be harnessed to induce emotional and physiological responses that can improve human health and wellbeing.

  5. Enhancement of retronasal odors by taste.

    Science.gov (United States)

    Green, Barry G; Nachtigal, Danielle; Hammond, Samuel; Lim, Juyun

    2012-01-01

    Psychophysical studies of interactions between retronasal olfaction and taste have focused most often on the enhancement of tastes by odors, which has been attributed primarily to a response bias (i.e., halo dumping). Based upon preliminary evidence that retronasal odors could also be enhanced by taste, the present study measured both forms of enhancement using appropriate response categories. In the first experiment, subjects rated taste ("sweet," "sour," "salty," and "bitter") and odor ("other") intensity for aqueous samples of 3 tastants (sucrose, NaCl, and citric acid) and 3 odorants (vanillin, citral, and furaneol), both alone and in taste-odor mixtures. The results showed that sucrose, but not the other taste stimuli, significantly increased the perceived intensity of all 3 odors. Enhancement of tastes by odors was inconsistent and generally weaker than enhancement of odors by sucrose. A second experiment used a flavored beverage and a custard dessert to test whether the findings from the first experiment would hold for the perception of actual foods. Adding sucrose significantly enhanced the intensity of "cherry" and "vanilla" flavors, whereas adding vanillin did not significantly enhance the intensity of sweetness. It is proposed that enhancement of retronasal odors by a sweet stimulus results from an adaptive sensory mechanism that serves to increase the salience of the flavor of nutritive foods. © The Author 2011. Published by Oxford University Press. All rights reserved.

  6. Visualizing mushroom body response to a conditioned odor in honeybees

    Science.gov (United States)

    Faber, Till; Menzel, Randolf

    2001-11-01

    Combining differential conditioning with optophysiological recordings of bee brain activity allows the investigation of learning-related changes in complex neural systems. In this study we focused on the mushroom bodies of the bee brain. Presenting different odors to the animal leads to significant activation of the mushroom body lips. After differential conditioning, the rewarded odor leads to stronger activation than it did before training. Activation by the unrewarded odor remains unchanged. These results resemble findings in the bee's antennal lobes, which are the first olfactory relay station in the insect brain. As an integrative neural network, enhanced activation of the mushroom body lip may carry additional information, i.e., for processing odor concentrations.

  7. Multi-Sensor Integration to Map Odor Distribution for the Detection of Chemical Sources

    Directory of Open Access Journals (Sweden)

    Xiang Gao

    2016-07-01

    Full Text Available This paper addresses the problem of mapping odor distribution derived from a chemical source using multi-sensor integration and reasoning system design. Odor localization is the problem of finding the source of an odor or other volatile chemical. Most localization methods require a mobile vehicle to follow an odor plume along its entire path, which is time consuming and may be especially difficult in a cluttered environment. To solve both of the above challenges, this paper proposes a novel algorithm that combines data from odor and anemometer sensors, and combine sensors’ data at different positions. Initially, a multi-sensor integration method, together with the path of airflow was used to map the pattern of odor particle movement. Then, more sensors are introduced at specific regions to determine the probable location of the odor source. Finally, the results of odor source location simulation and a real experiment are presented.

  8. Recovery of agricultural odors and odorous compounds from polyvinyl fluoride film bags

    Science.gov (United States)

    Accurate sampling methods are necessary when quantifying odor and volatile organic compound emissions at agricultural facilities. The commonly accepted methodology in the U.S. has been to collect odor samples in polyvinyl fluoride bags (PVF, brand name Tedlar®) and, subsequently, analyze with human ...

  9. [Effects of odor cue on morphine-induced dependence and craving in mice].

    Science.gov (United States)

    Liu, Xiao-Fen; Yang, Guang; Yang, Rui; Jia, Qiang; Guan, Su-Dong

    2012-04-01

    The olfactory system may play a pivotal role in drug addiction. To clarify the issues, we investigated the morphine dependence and psychological craving in morphine addicted mice using the conditioned place preference (CPP) paradigm by taking an only odor cue as the conditioned stimulus (CS). The results showed that by pairing morphine with odor, the CPP could be induced in mice. When the morphine addicted mice were exposed to a novel environment during morphine withdrawal, they spent significantly longer time in the chamber with morphine-paired odor than in the control chamber. The effects of odor cue on the morphine CPP were blocked by the administration of dopamine D1 or D2 antagonists. The studies indicated that olfactory system plays an important role in drug addiction.

  10. Do ambient urban odors evoke basic emotions?

    Directory of Open Access Journals (Sweden)

    Sandra Theresia Weber-Glass

    2014-04-01

    Full Text Available Fragrances, such as plant odors, have been shown to evoke autonomic response patterns associated with Ekman’s (Ekman et al., 1983 basic emotions happiness, surprise, anger, fear, sadness and disgust. Inducing positive emotions by odors in highly frequented public spaces could serve to improve the quality of life in urban environments. Thus, the present study evaluated the potency of ambient odors connoted with an urban environment to evoke basic emotions on an autonomic and cognitive response level. Synthetic mixtures representing the odors of disinfectant, candles / bees wax, summer air, burnt smell, vomit and musty smell as well as odorless water as a control were presented five times in random order to 30 healthy, non-smoking human subjects with intact sense of smell. Skin temperature, skin conductance, breathing rate, forearm muscle activity, blink rate and heart rate were recorded simultaneously. Subjects rated the odors in terms of pleasantness, intensity and familiarity and gave verbal labels to each odor as well as cognitive associations with the basic emotions. The results showed that the amplitude of the skin conductance response varied as a function of odor presentation. Burnt smell and vomit elicited significantly higher electrodermal responses than summer air. Also, a negative correlation was revealed between the amplitude of the skin conductance response and hedonic odor valence indicating that the magnitude of the electrodermal response increased with odor unpleasantness. The analysis of the cognitive associations between odors and basic emotions showed that candles / bees wax and summer air were specifically associated with happiness whereas burnt smell and vomit were uniquely associated with disgust. Our findings suggest that city odors may evoke specific cognitive associations of basic emotions and that autonomic activity elicited by such odors is related to odor hedonics.

  11. Ensemble response in mushroom body output neurons of the honey bee outpaces spatiotemporal odor processing two synapses earlier in the antennal lobe.

    Directory of Open Access Journals (Sweden)

    Martin F Strube-Bloss

    Full Text Available Neural representations of odors are subject to computations that involve sequentially convergent and divergent anatomical connections across different areas of the brains in both mammals and insects. Furthermore, in both mammals and insects higher order brain areas are connected via feedback connections. In order to understand the transformations and interactions that this connectivity make possible, an ideal experiment would compare neural responses across different, sequential processing levels. Here we present results of recordings from a first order olfactory neuropile - the antennal lobe (AL - and a higher order multimodal integration and learning center - the mushroom body (MB - in the honey bee brain. We recorded projection neurons (PN of the AL and extrinsic neurons (EN of the MB, which provide the outputs from the two neuropils. Recordings at each level were made in different animals in some experiments and simultaneously in the same animal in others. We presented two odors and their mixture to compare odor response dynamics as well as classification speed and accuracy at each neural processing level. Surprisingly, the EN ensemble significantly starts separating odor stimuli rapidly and before the PN ensemble has reached significant separation. Furthermore the EN ensemble at the MB output reaches a maximum separation of odors between 84-120 ms after odor onset, which is 26 to 133 ms faster than the maximum separation at the AL output ensemble two synapses earlier in processing. It is likely that a subset of very fast PNs, which respond before the ENs, may initiate the rapid EN ensemble response. We suggest therefore that the timing of the EN ensemble activity would allow retroactive integration of its signal into the ongoing computation of the AL via centrifugal feedback.

  12. Circuit oscillations in odor perception and memory.

    Science.gov (United States)

    Kay, Leslie M

    2014-01-01

    Olfactory system neural oscillations as seen in the local field potential have been studied for many decades. Recent research has shown that there is a functional role for the most studied gamma oscillations (40-100Hz in rats and mice, and 20Hz in insects), without which fine odor discrimination is poor. When these oscillations are increased artificially, fine discrimination is increased, and when rats learn difficult and highly overlapping odor discriminations, gamma is increased in power. Because of the depth of study on this oscillation, it is possible to point to specific changes in neural firing patterns as represented by the increase in gamma oscillation amplitude. However, we know far less about the mechanisms governing beta oscillations (15-30Hz in rats and mice), which are best associated with associative learning of responses to odor stimuli. These oscillations engage every part of the olfactory system that has so far been tested, plus the hippocampus, and the beta oscillation frequency band is the one that is most reliably coherent with other regions during odor processing. Respiratory oscillations overlapping with the theta frequency band (2-12Hz) are associated with odor sniffing and normal breathing in rats. They also show coupling in some circumstances between olfactory areas and rare coupling between the hippocampus and olfactory bulb. The latter occur in specific learning conditions in which coherence strength is negatively or positively correlated with performance, depending on the task. There is still much to learn about the role of neural oscillations in learning and memory, but techniques that have been brought to bear on gamma oscillations (current source density, computational modeling, slice physiology, behavioral studies) should deliver much needed knowledge of these events. © 2014 Elsevier B.V. All rights reserved.

  13. Analysis and control of odors from petroleum refineries

    International Nuclear Information System (INIS)

    O'Brien, M.A.; Duffee, R.A.; Ostojic, N.

    1992-01-01

    This paper presents a proven approach used to effectively solve odor problems associated with atmospheric emissions from petroleum refineries. A systematic evaluation is first conducted to identify all emissions with the potential for off-site odor impacts. Sampling is then conducted and dynamic dilution olfactometry is used to quantify the odor emission rates of each source. Community odor surveys are performed simultaneously with the source sampling to quantitatively document the downwind odor impacts. Atmospheric dispersion modeling specifically designed for odor is then used to predict instantaneous odor occurrences at various receptor sites under meteorological conditions not actually encountered during the field study. The findings make it possible to rank sources by their odor emission rates and potential for odor impacts in the community. It is then possible to determine how much odor reduction is required to bring the present odor impacts of the individual sources to an acceptable level under worst-case meteorological conditions. Once the degree of control required is determined, control alternatives are selected and evaluated. Case histories have been selected to illustrate the application of this approach at petroleum refineries. They provide descriptions of odor assessment and abatement studies conducted specifically for refinery effluent treatment plant sources as well as process unit emission sources. The sources identified as needing control and the odor abatement measures taken are discussed

  14. Olfactory aversive conditioning alters olfactory bulb mitral/tufted cell glomerular odor responses

    Directory of Open Access Journals (Sweden)

    Max L Fletcher

    2012-03-01

    Full Text Available The anatomical organization of receptor neuron input into the olfactory bulb (OB allows odor information to be transformed into an odorant-specific spatial map of mitral/tufted cell glomerular activity at the upper level of the olfactory bulb. In other sensory systems, neuronal representations of stimuli can be reorganized or enhanced following learning. While the mammalian OB has been shown to undergo experience-dependent plasticity at the glomerular level, it is still unclear if similar representational change occurs within mitral/tufted cell glomerular odor representations following learning. To address this, odorant-evoked glomerular activity patterns were imaged in mice expressing a GFP-based calcium indicator (GCaMP2 in OB mitral/tufted cells. Glomerular odor responses were imaged before and after olfactory associative conditioning to aversive foot shock. Following conditioning, we found no overall reorganization of the glomerular representation. Training, however, did significantly alter the amplitudes of individual glomeruli within the representation in mice in which the odor was presented together with foot shock. Further, the specific pairing of foot shock with odor presentations lead to increased responses primarily in initially weakly activated glomeruli. Overall, these results suggest that associative conditioning can enhance the initial representation of odors within the olfactory bulb by enhancing responses to the learned odor in some glomeruli.

  15. Chemosensory danger detection in the human brain: Body odor communicating aggression modulates limbic system activation.

    Science.gov (United States)

    Mutic, Smiljana; Brünner, Yvonne F; Rodriguez-Raecke, Rea; Wiesmann, Martin; Freiherr, Jessica

    2017-05-01

    Although the sense of smell is involved in numerous survival functions, the processing of body odor emitted by dangerous individuals is far from understood. The aim of the study was to explore how human fight chemosignals communicating aggression can alter brain activation related to an attentional bias and danger detection. While the anterior cingulate cortex (ACC) was seen involved in processing threat-related emotional information, danger detection and error evaluation, it still remains unknown whether human chemosignals communicating aggression can potentially modulate this activation. In the fMRI experiment, healthy male and female normosmic odor recipients (n=18) completed a higher-order processing task (emotional Stroop task with the word categories anger, anxiety, happiness and neutral) while exposed to aggression and exercise chemosignals (collected from a different group of healthy male donors; n=16). Our results provide first evidence that aggression chemosignals induce a time-sensitive attentional bias in chemosensory danger detection and modulate limbic system activation. During exposure to aggression chemosignals compared to exercise chemosignals, functional imaging data indicates an enhancement of thalamus, hypothalamus and insula activation (pbody odor signals are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Nested Expression Domains for Odorant Receptors in Zebrafish Olfactory Epithelium

    Science.gov (United States)

    Weth, Franco; Nadler, Walter; Korsching, Sigrun

    1996-11-01

    The mapping of high-dimensional olfactory stimuli onto the two-dimensional surface of the nasal sensory epithelium constitutes the first step in the neuronal encoding of olfactory input. We have used zebrafish as a model system to analyze the spatial distribution of odorant receptor molecules in the olfactory epithelium by quantitative in situ hybridization. To this end, we have cloned 10 very divergent zebrafish odorant receptor molecules by PCR. Individual genes are expressed in sparse olfactory receptor neurons. Analysis of the position of labeled cells in a simplified coordinate system revealed three concentric, albeit overlapping, expression domains for the four odorant receptors analyzed in detail. Such regionalized expression should result in a corresponding segregation of functional response properties. This might represent the first step of spatial encoding of olfactory input or be essential for the development of the olfactory system.

  17. Functional neuronal processing of human body odors.

    Science.gov (United States)

    Lundström, Johan N; Olsson, Mats J

    2010-01-01

    Body odors carry informational cues of great importance for individuals across a wide range of species, and signals hidden within the body odor cocktail are known to regulate several key behaviors in animals. For a long time, the notion that humans may be among these species has been dismissed. We now know, however, that each human has a unique odor signature that carries information related to his or her genetic makeup, as well as information about personal environmental variables, such as diet and hygiene. Although a substantial number of studies have investigated the behavioral effects of body odors, only a handful have studied central processing. Recent studies have, however, demonstrated that the human brain responds to fear signals hidden within the body odor cocktail, is able to extract kin specific signals, and processes body odors differently than other perceptually similar odors. In this chapter, we provide an overview of the current knowledge of how the human brain processes body odors and the potential importance these signals have for us in everyday life. Copyright © 2010 Elsevier Inc. All rights reserved.

  18. The perception of odor objects in everyday life: a review on the processing of odor mixtures

    Directory of Open Access Journals (Sweden)

    Thierry eThomas-Danguin

    2014-06-01

    Full Text Available Smelling monomolecular odors hardly ever occurs in everyday life, and the daily functioning of the sense of smell relies primarily on the processing of complex mixtures of volatiles that are present in the environment (e.g., emanating from food or conspecifics. Such processing allows for the instantaneous recognition and categorization of smells and also for the discrimination of odors among others to extract relevant information and to adapt efficiently in different contexts. The neurophysiological mechanisms underpinning this highly efficient analysis of complex mixtures of odorants is beginning to be unraveled and support the idea that olfaction, as vision and audition, relies on odor-objects encoding. This configural processing of odor mixtures, which is empirically subject to important applications in our societies (e.g., the art of perfumers, flavorists, and wine makers, has been scientifically studied only during the last decades. This processing depends on many individual factors, among which are the developmental stage, lifestyle, physiological and mood state, and cognitive skills; this processing also presents striking similarities between species. The present review gathers the recent findings, as observed in animals, healthy subjects, and/or individuals with affective disorders, supporting the perception of complex odor stimuli as odor objects. It also discusses peripheral to central processing, and cognitive and behavioral significance. Finally, this review highlights that the study of odor mixtures is an original window allowing for the investigation of daily olfaction and emphasizes the need for knowledge about the underlying biological processes, which appear to be crucial for our representation and adaptation to the chemical environment.

  19. Modification of CO2 avoidance behaviour in Drosophila by inhibitory odorants.

    Science.gov (United States)

    Turner, Stephanie Lynn; Ray, Anandasankar

    2009-09-10

    The fruitfly Drosophila melanogaster exhibits a robust and innate olfactory-based avoidance behaviour to CO(2), a component of odour emitted from stressed flies. Specialized neurons in the antenna and a dedicated neuronal circuit in the higher olfactory system mediate CO(2) detection and avoidance. However, fruitflies need to overcome this avoidance response in some environments that contain CO(2) such as ripening fruits and fermenting yeast, which are essential food sources. Very little is known about the molecular and neuronal basis of this unique, context-dependent modification of innate olfactory avoidance behaviour. Here we identify a new class of odorants present in food that directly inhibit CO(2)-sensitive neurons in the antenna. Using an in vivo expression system we establish that the odorants act on the Gr21a/Gr63a CO(2) receptor. The presence of these odorants significantly and specifically reduces CO(2)-mediated avoidance behaviour, as well as avoidance mediated by 'Drosophila stress odour'. We propose a model in which behavioural avoidance to CO(2) is directly influenced by inhibitory interactions of the novel odours with CO(2) receptors. Furthermore, we observe differences in the temporal dynamics of inhibition: the effect of one of these odorants lasts several minutes beyond the initial exposure. Notably, animals that have been briefly pre-exposed to this odorant do not respond to the CO(2) avoidance cue even after the odorant is no longer present. We also show that related odorants are effective inhibitors of the CO(2) response in Culex mosquitoes that transmit West Nile fever and filariasis. Our findings have broader implications in highlighting the important role of inhibitory odorants in olfactory coding, and in their potential to disrupt CO(2)-mediated host-seeking behaviour in disease-carrying insects like mosquitoes.

  20. Odors pulsed at wing beat frequencies are tracked by primary olfactory networks and enhance odor detection

    Directory of Open Access Journals (Sweden)

    Shreejoy Tripathy

    2010-03-01

    Full Text Available Each down stroke of an insect’s wings accelerates axial airflow over the antennae. Modeling studies suggest that this can greatly enhance penetration of air and air-born odorants through the antennal sensilla thereby periodically increasing odorant-receptor interactions. Do these periodic changes result in entrainment of neural responses in the antenna and antennal lobe (AL? Does this entrainment affect olfactory acuity? To address these questions, we monitored antennal and AL responses in the moth Manduca sexta while odorants were pulsed at frequencies from 10-72 Hz, encompassing the natural wingbeat frequency. Power spectral density (PSD analysis was used to identify entrainment of neural activity. Statistical analysis of PSDs indicates that the antennal nerve tracked pulsed odor up to 30 Hz. Furthermore, at least 50% of AL local field potentials (LFPs and between 7-25% of unitary spiking responses also tracked pulsed odor up to 30 Hz in a frequency-locked manner. Application of bicuculline (200µM abolished pulse tracking in both LFP and unitary responses suggesting that GABAA receptor activation is necessary for pulse tracking within the AL. Finally, psychophysical measures of odor detection establish that detection thresholds are lowered when odor is pulsed at 20 Hz. These results suggest that AL networks can respond to the oscillatory dynamics of stimuli such as those imposed by the wing beat in a manner analogous to mammalian sniffing.

  1. Positive implicit attitudes toward odor words.

    Science.gov (United States)

    Bulsing, Patricia J; Smeets, Monique A M; van den Hout, Marcel A

    2007-07-01

    Associations between certain odors and for instance health effects may lead to positive or negative attitudes toward these odors. However, in experiments we conducted using the Implicit Association Test (IAT), we encountered attitudes even to odor "words." The IAT is based on the principle that reaction times measuring the association between words from a target dimension (in this case, odor vs. a neutral reference category) and an attribute dimension (i.e., positive or negative words) reflect the attitude to the target, where attitude-congruent associations between target and attribute are reflected by shorter reaction times. In a first experiment, we found distinctly positive attitudes to the concept odor in a student sample, which was replicated in a second experiment. In the main experiment, subjects in the aromatherapy group, who prefer using scented consumer products for relaxation purposes, showed a significantly more positive attitude toward odor words in the IAT than a control group, who did not have such a preference. The fact that results from the implicit test were not always associated with explicitly stated attitudes toward the odor words attests to the fact that the IAT measures the attitude of interest in a different way. As such, the IAT has added value in circumstances where explicit tests can be biased.

  2. Food-Related Odors Activate Dopaminergic Brain Areas

    Directory of Open Access Journals (Sweden)

    Agnieszka Sorokowska

    2017-12-01

    Full Text Available Food-associated cues of different sensory categories have often been shown to be a potent elicitor of cerebral activity in brain reward circuits. Smells influence and modify the hedonic qualities of eating experience, and in contrast to smells not associated with food, perception of food-associated odors may activate dopaminergic brain areas. In this study, we aimed to verify previous findings related to the rewarding value of food-associated odors by means of an fMRI design involving carefully preselected odors of edible and non-edible substances. We compared activations generated by three food and three non-food odorants matching in terms of intensity, pleasantness and trigeminal qualities. We observed that for our mixed sample of 30 hungry and satiated participants, food odors generated significantly higher activation in the anterior cingulate cortex (right and left, insula (right, and putamen (right than non-food odors. Among hungry subjects, regardless of the odor type, we found significant activation in the ventral tegmental area in response to olfactory stimulation. As our stimuli were matched in terms of various perceptual qualities, this result suggests that edibility of an odor source indeed generates specific activation in dopaminergic brain areas.

  3. Characterization of odor-active volatiles in apples: influence of cultivars and maturity stage.

    Science.gov (United States)

    Mehinagic, Emira; Royer, Gaëlle; Symoneaux, Ronan; Jourjon, Frédérique; Prost, Carole

    2006-04-05

    The aroma and texture of three different apple cultivars, harvested at three maturity stages, were analyzed by sensory and instrumental analysis. The emphasis was on the identification of the most potent odorant volatiles, and the challenge was to separate the few most important flavor compounds, which may be trace chemicals, from the vast number of nonodorant compounds present in apple aroma extracts. Thirty-six odorant compounds were detected, 24 of which were common to all extracts. A significant correlation coefficient was found between the aroma intensity scores and overall quantity of the odorant volatiles, which shows that the development of sensory aroma is similar to that of odorant volatiles. This study also showed that the parameters measured by penetrometry and compression were highly correlated with sensory textural attributes. The determination of the optimal maturity stage for different apple cultivars by the usual parameters, such as color, diameter, total soluble solids, and titrable acidity, may not be sufficient to determine the optimal sensory quality for consumers. Moreover, the sensory quality of fruits changes during maturation in a different way from one cultivar to another, and this should be taken into account.

  4. Nurse odor perception in various Japanese hospital settings

    Directory of Open Access Journals (Sweden)

    Masami Horiguchi

    2015-12-01

    Full Text Available Because unpleasant hospital odors affect the nursing environment, we investigated nurses' perceptions of the odors of various hospital settings: hospital rooms, nurse stations, and human waste disposal rooms to discard the urine, stools and diapers. A questionnaire based on the Japanese Ministry of the Environment's guidelines on odor index regulation was used to assess nurses' perceptions of odor intensity, comfort, tolerability, and description in the aforementioned settings. Questionnaires were distributed to nursing department directors at three Japanese hospitals, who then disseminated the questionnaires to nursing staff. Of the 1,151 questionnaires distributed, 496 nurses participated. Human waste disposal rooms had greater odor intensity and were perceived as more uncomfortable than the other settings. Unpleasant odors in disposal rooms, hospital rooms, and nurse stations were rated as slightly intolerable in comparison. Hospital and disposal rooms were mainly described as having a “pungent odor such as of urine and stool.” In contrast, nurse stations were described as having other unpleasant odors, such as chemical, human-body-related, or sewage-like odors. Given that nurses spend much of their time in hospital rooms and nurse stations, odor management in these two settings would likely improve nurses' working conditions at hospitals. Improving odors at nurse stations is feasible. Such improvements could have indirect effects on nurse turnover and burnout.

  5. An odor flux model for cattle feedlots

    Energy Technology Data Exchange (ETDEWEB)

    Ormerod, R.J. [Dames & Moore, Brisbane (Australia)

    1994-12-31

    Odor nuisance associated with cattle feedlots has been an issue of major interest and concern to regulators, rural communities and the beef industry in Australia over the past decade. Methods of assessing the likely impacts of new feedlots on community odor exposure are still being developed, but in the past few years much has been learnt about the processes of odor generation, flux and dispersion as well as the acceptability of feedlot odor to exposed communities. This paper outlines a model which simulates the complex physical and chemical processes leading to odor emissions in a simple and practical framework. The model, named BULSMEL, has been developed as a response to regulatory requirements for quantitative assessments of odor impact. It will continue to be refined as more data are gathered.

  6. Construction of taste-odor recognitition system using optimized sensory device; Kankaku tekio sensa wo mochiita aji/nioi shikibetsu sisutemu no kosei

    Energy Technology Data Exchange (ETDEWEB)

    Osada, H.; Yoshida, H.; Omamiuda, Y.; Ajishi, Y.; Seki, K. [Iwate University, Iwate (Japan); Kikuchi, S. [Tohoku Gakuin University, Miyagi (Japan)

    1997-06-20

    Until now, the quality of foods, that is, as the electrical measuring method of taste and odor, the utilizing method of artificial fatty films and ceramics of ZnO and so on are devised and put to practical use. However, the field of measuring of taste and odor is a comparative new field, and it is still developing stage in the lasting quality and so on. To measure the quality of foods holds an important position in the safety management, together with supporting the development of products as the needs of user. Authors studied a new taste/odor sensor utilizing the optimized sensory device (OSD) which is prepared from sintering the mixture of the magnetic semiconductor powder such as Mn-An ferrite and ruthenium compound. When various taste and odor components included in food adheres to the OSD, resistance or electromotive force faced on surface electric conduction of the OSD change, therefore it can be clearly discriminated the sort and quality of foods. This paper describes preparation of a thick-film OSD and construction of the multi-channel taste/odor recognition system for some drinks. 12 refs., 13 figs.

  7. Development switch in neural circuitry underlying odor-malaise learning.

    Science.gov (United States)

    Shionoya, Kiseko; Moriceau, Stephanie; Lunday, Lauren; Miner, Cathrine; Roth, Tania L; Sullivan, Regina M

    2006-01-01

    Fetal and infant rats can learn to avoid odors paired with illness before development of brain areas supporting this learning in adults, suggesting an alternate learning circuit. Here we begin to document the transition from the infant to adult neural circuit underlying odor-malaise avoidance learning using LiCl (0.3 M; 1% of body weight, ip) and a 30-min peppermint-odor exposure. Conditioning groups included: Paired odor-LiCl, Paired odor-LiCl-Nursing, LiCl, and odor-saline. Results showed that Paired LiCl-odor conditioning induced a learned odor aversion in postnatal day (PN) 7, 12, and 23 pups. Odor-LiCl Paired Nursing induced a learned odor preference in PN7 and PN12 pups but blocked learning in PN23 pups. 14C 2-deoxyglucose (2-DG) autoradiography indicated enhanced olfactory bulb activity in PN7 and PN12 pups with odor preference and avoidance learning. The odor aversion in weanling aged (PN23) pups resulted in enhanced amygdala activity in Paired odor-LiCl pups, but not if they were nursing. Thus, the neural circuit supporting malaise-induced aversions changes over development, indicating that similar infant and adult-learned behaviors may have distinct neural circuits.

  8. Sensory memory for odors is encoded in spontaneous correlated activity between olfactory glomeruli.

    Science.gov (United States)

    Galán, Roberto F; Weidert, Marcel; Menzel, Randolf; Herz, Andreas V M; Galizia, C Giovanni

    2006-01-01

    Sensory memory is a short-lived persistence of a sensory stimulus in the nervous system, such as iconic memory in the visual system. However, little is known about the mechanisms underlying olfactory sensory memory. We have therefore analyzed the effect of odor stimuli on the first odor-processing network in the honeybee brain, the antennal lobe, which corresponds to the vertebrate olfactory bulb. We stained output neurons with a calcium-sensitive dye and measured across-glomerular patterns of spontaneous activity before and after a stimulus. Such a single-odor presentation changed the relative timing of spontaneous activity across glomeruli in accordance with Hebb's theory of learning. Moreover, during the first few minutes after odor presentation, correlations between the spontaneous activity fluctuations suffice to reconstruct the stimulus. As spontaneous activity is ubiquitous in the brain, modifiable fluctuations could provide an ideal substrate for Hebbian reverberations and sensory memory in other neural systems.

  9. Advantage of the Highly Restricted Odorant Receptor Expression Pattern in Chemosensory Neurons of Drosophila.

    Science.gov (United States)

    Tharadra, Sana Khalid; Medina, Adriana; Ray, Anandasankar

    2013-01-01

    A fundamental molecular feature of olfactory systems is that individual neurons express only one receptor from a large odorant receptor gene family. While numerous theories have been proposed, the functional significance and evolutionary advantage of generating a sophisticated one-receptor-per neuron expression pattern is not well understood. Using the genetically tractable Drosophila melanogaster as a model, we demonstrate that the breakdown of this highly restricted expression pattern of an odorant receptor in neurons leads to a deficit in the ability to exploit new food sources. We show that animals with ectopic co-expression of odorant receptors also have a competitive disadvantage in a complex environment with limiting food sources. At the level of the olfactory system, we find changes in both the behavioral and electrophysiological responses to odorants that are detected by endogenous receptors when an olfactory receptor is broadly misexpressed in chemosensory neurons. Taken together these results indicate that restrictive expression patterns and segregation of odorant receptors to individual neuron classes are important for sensitive odor-detection and appropriate olfactory behaviors.

  10. The differential mice response to cat and snake odor.

    Science.gov (United States)

    de Oliveira Crisanto, Karen; de Andrade, Wylqui Mikael Gomes; de Azevedo Silva, Kayo Diogenes; Lima, Ramón Hypolito; de Oliveira Costa, Miriam Stela Maris; de Souza Cavalcante, Jeferson; de Lima, Ruthnaldo Rodrigues Melo; do Nascimento, Expedito Silva; Cavalcante, Judney Cley

    2015-12-01

    Studies from the last two decades have pointed to multiple mechanisms of fear. For responding to predators, there is a group of highly interconnected hypothalamic nuclei formed by the anterior hypothalamic nucleus, the ventromedial hypothalamic nucleus and the dorsal premammillary nucleus—the predator-responsive hypothalamic circuit. This circuit expresses Fos in response to predator presence or its odor. Lesion of any component of this system blocks or reduces the expression of fear and consequently defensive behavior when faced with a predator or its cue. However, most of the knowledge about that circuit has been obtained using the rat as a model of prey and the cat as a source of predator cues. In the present study, we exposed mice to strong cat or snake odors, two known mice predators, and then we used the rat exposure test (RET) to study their behavior when confronted with the same predator's odor. Our data point to a differential response of mice exposed to these odors. When Swiss mice were exposed to the cat odor, they show defensive behavior and the predator-responsive hypothalamic circuit expressed Fos. The opposite was seen when they faced snake's odor. The acute odor exposure was not sufficient to activate the mouse predator-responsive hypothalamic circuit and the mice acted like they were not in a stressful situation, showing almost no sign of fear or defensive posture. This leads us to the conclusion that not all the predator cues are sufficient to activate the predator-responsive hypothalamic circuit of mice and that their response depends on the danger that these predators represent in the natural history of the prey.

  11. Autonomous Micro-Air-Vehicle Control Based on Visual Sensing for Odor Source Localization

    Directory of Open Access Journals (Sweden)

    Kenzo Kurotsuchi

    2017-07-01

    Full Text Available In this paper, we propose a novel control method for autonomous-odor-source localization using visual and odor sensing by micro air vehicles (MAVs. Our method is based on biomimetics, which enable highly autonomous localization. Our method does not need any instruction signals, including even global positioning system (GPS signals. An experimenter simply blows a whistle, and the MAV will then start to hover, to seek an odor source, and to keep hovering near the source. The GPS-signal-free control based on visual sense enables indoor/underground use. Moreover, the MAV is light-weight (85 grams and does not cause harm to others even if it accidentally falls. Experiments conducted in the real world were successful in enabling odor source localization using the MAV with a bio-inspired searching method. The distance error of the localization was 63 cm, more accurate than the target distance of 120 cm for individual identification. Our odor source localization is the first step to a proof of concept for a danger warning system. These localization experiments were the first step to a proof of concept for a danger warning system to enable a safer and more secure society.

  12. Potential for reduction of odorous compounds in swine manure through diet modification.

    Science.gov (United States)

    Sutton, A L; Kephart, K B; Verstegen, M W; Canh, T T; Hobbs, P J

    1999-02-01

    Recent public concern about air pollution from pork production units has prompted more research to develop methods to reduce and control odors. Masking agents, enzymes and bacterial preparations, feed additives, chemicals, oxidation processes, air scrubbers, biofilters, and new ventilation systems have been studied. Research relating the effects of the swine diet on manure odors has been scarce. Introducing feed additives to bind ammonia, change digesta pH, affect specific enzyme activity, and mask odors has been either costly or not consistently successful. Recent research emphasis has focused on manipulating the diet 1) to increase the nutrient utilization of the diet to reduce excretion products, 2) to enhance microbial metabolism in the lower digestive tract to reduce excretion of odor-causing compounds, and 3) to change the physical characteristics of urine and feces to reduce odor emissions. Primary odor-causing compounds evolve from excess degradable proteins and lack of specific fermentable carbohydrates during microbial fermentation. Reductions in ammonia emissions by 28 to 79% through diet modifications have been reported. Limited research on reduction of other odorous volatile organic compounds through diet modifications is promising. Use of synthetic amino acids with reduced intact protein levels in diets significantly reduces nitrogen excretions and odor production. Addition of nonstarch polysaccharides and specific oligosaccharides further alters the pathway of nitrogen excretion and reduces odor emission. Continued nutritional and microbial research to incorporate protein degradation products, especially sulfur-containing organics, with fermentable carbohydrates in the lower gastrointestinal tract of pigs will further control odors from manure.

  13. Body odors promote automatic imitation in autism.

    Science.gov (United States)

    Parma, Valentina; Bulgheroni, Maria; Tirindelli, Roberto; Castiello, Umberto

    2013-08-01

    Autism spectrum disorders comprise a range of neurodevelopmental pathologies characterized, among other symptoms, by impaired social interactions. Individuals with this diagnosis are reported to often identify people by repetitively sniffing pieces of clothing or the body odor of family members. Since body odors are known to initiate and mediate many different social behaviors, smelling the body odor of a family member might constitute a sensory-based action promoting social contact. In light of this, we hypothesized that the body odor of a family member would facilitate the appearance of automatic imitation, an essential social skill known to be impaired in autism. We recruited 20 autistic and 20 typically developing children. Body odors were collected from the children's mothers' axillae. A child observed a model (their mother or a stranger mother) execute (or not) a reach-to-grasp action toward an object. Subsequently, she performed the same action. The object was imbued with the child's mother's odor, a stranger mother's odor, or no odor. The actions were videotaped, and movement time was calculated post hoc via a digitalization technique. Automatic imitation effects-expressed in terms of total movement time reduction-appear in autistic children only when exposed to objects paired with their own mother's odor. The maternal odor, which conveys a social message otherwise neglected, helps autistic children to covertly imitate the actions of others. Our results represent a starting point holding theoretical and practical relevance for the development of new strategies to enhance communication and social behavior among autistic individuals. Copyright © 2013 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  14. Body Odor (For Young Men)

    Science.gov (United States)

    ... Sexual Health Medical Conditions Nutrition & Fitness Emotional Health Body Odor Posted under Health Guides . Updated 23 March 2017. + ... every guy has to deal with. What causes body odor? During puberty, your sweat glands become much more ...

  15. Noradrenergic Control of Odor Recognition in a Nonassociative Olfactory Learning Task in the Mouse

    Science.gov (United States)

    Veyrac, Alexandra; Nguyen, Veronique; Marien, Marc; Didier, Anne; Jourdan, Francois

    2007-01-01

    The present study examined the influence of pharmacological modulations of the locus coeruleus noradrenergic system on odor recognition in the mouse. Mice exposed to a nonrewarded olfactory stimulation (training) were able to memorize this odor and to discriminate it from a new odor in a recall test performed 15 min later. At longer delays (30 or…

  16. A Fusion Approach to Feature Extraction by Wavelet Decomposition and Principal Component Analysis in Transient Signal Processing of SAW Odor Sensor Array

    Directory of Open Access Journals (Sweden)

    Prashant SINGH

    2011-03-01

    Full Text Available This paper presents theoretical analysis of a new approach for development of surface acoustic wave (SAW sensor array based odor recognition system. The construction of sensor array employs a single polymer interface for selective sorption of odorant chemicals in vapor phase. The individual sensors are however coated with different thicknesses. The idea of sensor coating thickness variation is for terminating solvation and diffusion kinetics of vapors into polymer up to different stages of equilibration on different sensors. This is expected to generate diversity in information content of the sensors transient. The analysis is based on wavelet decomposition of transient signals. The single sensor transients have been used earlier for generating odor identity signatures based on wavelet approximation coefficients. In the present work, however, we exploit variability in diffusion kinetics due to polymer thicknesses for making odor signatures. This is done by fusion of the wavelet coefficients from different sensors in the array, and then applying the principal component analysis. We find that the present approach substantially enhances the vapor class separability in feature space. The validation is done by generating synthetic sensor array data based on well-established SAW sensor theory.

  17. Quantitative method to determine the regional drinking water odorant regulation goals based on odor sensitivity distribution: illustrated using 2-MIB.

    Science.gov (United States)

    Yu, Jianwei; An, Wei; Cao, Nan; Yang, Min; Gu, Junong; Zhang, Dong; Lu, Ning

    2014-07-01

    Taste and odor (T/O) in drinking water often cause consumer complaints and are thus regulated in many countries. However, people in different regions may exhibit different sensitivities toward T/O. This study proposed a method to determine the regional drinking water odorant regulation goals (ORGs) based on the odor sensitivity distribution of the local population. The distribution of odor sensitivity to 2-methylisoborneol (2-MIB) by the local population in Beijing, China was revealed by using a normal distribution function/model to describe the odor complaint response to a 2-MIB episode in 2005, and a 2-MIB concentration of 12.9 ng/L and FPA (flavor profile analysis) intensity of 2.5 was found to be the critical point to cause odor complaints. Thus the Beijing ORG for 2-MIB was determined to be 12.9 ng/L. Based on the assumption that the local FPA panel can represent the local population in terms of sensitivity to odor, and that the critical FPA intensity causing odor complaints was 2.5, this study tried to determine the ORGs for seven other cities of China by performing FPA tests using an FPA panel from the corresponding city. ORG values between 12.9 and 31.6 ng/L were determined, showing that a unified ORG may not be suitable for drinking water odor regulations. This study presents a novel approach for setting drinking water odor regulations. Copyright © 2014. Published by Elsevier B.V.

  18. Characteristic vibration patterns of odor compounds from bread-baking volatiles upon protein binding: density functional and ONIOM study and principal component analysis.

    Science.gov (United States)

    Treesuwan, Witcha; Hirao, Hajime; Morokuma, Keiji; Hannongbua, Supa

    2012-05-01

    As the mechanism underlying the sense of smell is unclear, different models have been used to rationalize structure-odor relationships. To gain insight into odorant molecules from bread baking, binding energies and vibration spectra in the gas phase and in the protein environment [7-transmembrane helices (7TMHs) of rhodopsin] were calculated using density functional theory [B3LYP/6-311++G(d,p)] and ONIOM [B3LYP/6-311++G(d,p):PM3] methods. It was found that acetaldehyde ("acid" category) binds strongly in the large cavity inside the receptor, whereas 2-ethyl-3-methylpyrazine ("roasted") binds weakly. Lys296, Tyr268, Thr118 and Ala117 were identified as key residues in the binding site. More emphasis was placed on how vibrational frequencies are shifted and intensities modified in the receptor protein environment. Principal component analysis (PCA) suggested that the frequency shifts of C-C stretching, CH(3) umbrella, C = O stretching and CH(3) stretching modes have a significant effect on odor quality. In fact, the frequency shifts of the C-C stretching and C = O stretching modes, as well as CH(3) umbrella and CH(3) symmetric stretching modes, exhibit different behaviors in the PCA loadings plot. A large frequency shift in the CH(3) symmetric stretching mode is associated with the sweet-roasted odor category and separates this from the acid odor category. A large frequency shift of the C-C stretching mode describes the roasted and oily-popcorn odor categories, and separates these from the buttery and acid odor categories.

  19. Female perception of male body odor.

    Science.gov (United States)

    Sergeant, Mark J T

    2010-01-01

    Olfaction is one of the most crucial forms of communication among nonhuman animals. Historically, olfaction has been perceived as being of limited importance for humans, but recent research has documented that not only do humans have sensitive olfactory abilities, but also odors have the potential to influence our physiology and behavior. This chapter reviews research on olfactory communication among humans, focusing on the effects of male bodily odors on female physiology and behavior. The process of body odor production and the detection of olfactory signals are reviewed, focusing on potential sex differences in these abilities. The effects of male body odors on female physiological and behavioral effects of body odors are considered. Finally, with specific regard to female mate choice, evidence regarding the influence of the major histocompatibility complex and fluctuating asymmetry on male olfactory cues is reviewed. Copyright © 2010 Elsevier Inc. All rights reserved.

  20. Altered Olfactory Processing of Stress Related Body Odors and Artificial Odors in Patients with Panic Disorder

    OpenAIRE

    Wintermann, Gloria-Beatrice; Donix, Markus; Joraschky, Peter; Gerber, Johannes; Petrowski, Katja

    2014-01-01

    Background: Patients with Panic Disorder (PD) direct their attention towards potential threat, followed by panic attacks, and increased sweat production. Onés own anxiety sweat odor influences the attentional focus, and discrimination of threat or non-threat. Since olfactory projection areas overlap with neuronal areas of a panic-specific fear network, the present study investigated the neuronal processing of odors in general and of stress-related sweat odors in particular in patients with PD...

  1. The effect of meat consumption on body odor attractiveness.

    Science.gov (United States)

    Havlicek, Jan; Lenochova, Pavlina

    2006-10-01

    Axillary body odor is individually specific and potentially a rich source of information about its producer. Odor individuality partly results from genetic individuality, but the influence of ecological factors such as eating habits are another main source of odor variability. However, we know very little about how particular dietary components shape our body odor. Here we tested the effect of red meat consumption on body odor attractiveness. We used a balanced within-subject experimental design. Seventeen male odor donors were on "meat" or "nonmeat" diet for 2 weeks wearing axillary pads to collect body odor during the final 24 h of the diet. Fresh odor samples were assessed for their pleasantness, attractiveness, masculinity, and intensity by 30 women not using hormonal contraceptives. We repeated the same procedure a month later with the same odor donors, each on the opposite diet than before. Results of repeated measures analysis of variance showed that the odor of donors when on the nonmeat diet was judged as significantly more attractive, more pleasant, and less intense. This suggests that red meat consumption has a negative impact on perceived body odor hedonicity.

  2. Unpleasant odors increase aversion to monetary losses.

    Science.gov (United States)

    Stancak, Andrej; Xie, Yuxin; Fallon, Nicholas; Bulsing, Patricia; Giesbrecht, Timo; Thomas, Anna; Pantelous, Athanasios A

    2015-04-01

    Loss aversion is the tendency to prefer avoiding losses over acquiring gains of equal nominal values. Unpleasant odors not only influence affective state but have also been shown to activate brain regions similar to those mediating loss aversion. Therefore, we hypothesized a stronger loss aversion in a monetary gamble task if gambles were associated with an unpleasant as opposed to pleasant odor. In thirty human subjects, unpleasant (methylmercaptan), pleasant (jasmine), and neutral (clean air) odors were presented for 4 s. At the same time, uncertain gambles offering an equal chance of gain or loss of a variable amount of money, or a prospect of an assured win were displayed. One hundred different gambles were presented three times, each time paired with a different odor. Loss aversion, risk aversion, and logit sensitivity were evaluated using non-linear fitting of individual gamble decisions. Loss aversion was larger when prospects were displayed in the presence of methylmercaptan compared to jasmine or clean air. Moreover, individual differences in changes in loss aversion to the unpleasant as compared to pleasant odor correlated with odor pleasantness but not with odor intensity. Skin conductance responses to losses during the outcome period were larger when gambles were associated with methylmercaptan compared to jasmine. Increased loss aversion while perceiving an unpleasant odor suggests a dynamic adjustment of loss aversion toward greater sensitivity to losses. Given that odors are biological signals of hazards, such adjustment of loss aversion may have adaptive value in situations entailing threat or danger. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Data on performance of air stripping tower- PAC integrated system for removing of odor, taste, dye and organic materials from drinking water-A case study in Saqqez, Iran

    Directory of Open Access Journals (Sweden)

    Meghdad Pirsaheb

    2018-06-01

    Full Text Available Unpleasant taste or smell are more importantly constituents of drinking-water, lead to complaints from consumers. Dye and organic matter as well change in disinfection practice may generate taste and an odorous compound in treated water. According to low efficiency of conventional methods to remove taste and odor compounds, present study was aimed to evaluate the performance of air stripping tower- Poly Aluminum Chloride (PAC integrated system to remove odor and taste, dye and organic materials from drinking water. Different air to water ratio and PAC doses were used to remove considered parameters in certain condition. The results of this study indicated that the maximum removal efficiency of 86.2, 76.47, 58.46 and 41.27% of taste and odor, dye, COD and TOC were achieved by the air stripping tower- PAC integrated system, respectively. However, the physico-chemical characteristics of water and adsorbent effect on the of substances removal efficiency considerably. It can be stated that the air striping tower - PAC integrated system is able to reduce the odor and taste-causing substances and organic matter to a level which is recommended by the Institute of Standards and Industrial Research of Iran. Keywords: Air stripping tower, PAC, Odor and Taste, Dye, Organic materials, Drinking water, Saqqez city

  4. Sparse distributed representation of odors in a large-scale olfactory bulb circuit.

    Directory of Open Access Journals (Sweden)

    Yuguo Yu

    Full Text Available In the olfactory bulb, lateral inhibition mediated by granule cells has been suggested to modulate the timing of mitral cell firing, thereby shaping the representation of input odorants. Current experimental techniques, however, do not enable a clear study of how the mitral-granule cell network sculpts odor inputs to represent odor information spatially and temporally. To address this critical step in the neural basis of odor recognition, we built a biophysical network model of mitral and granule cells, corresponding to 1/100th of the real system in the rat, and used direct experimental imaging data of glomeruli activated by various odors. The model allows the systematic investigation and generation of testable hypotheses of the functional mechanisms underlying odor representation in the olfactory bulb circuit. Specifically, we demonstrate that lateral inhibition emerges within the olfactory bulb network through recurrent dendrodendritic synapses when constrained by a range of balanced excitatory and inhibitory conductances. We find that the spatio-temporal dynamics of lateral inhibition plays a critical role in building the glomerular-related cell clusters observed in experiments, through the modulation of synaptic weights during odor training. Lateral inhibition also mediates the development of sparse and synchronized spiking patterns of mitral cells related to odor inputs within the network, with the frequency of these synchronized spiking patterns also modulated by the sniff cycle.

  5. A study on the composition of off-odor volatiles in irradiated pork

    International Nuclear Information System (INIS)

    Lin Ruotai; Geng Shengrong; Zhang Jinmu; Chen Yuxia; Liu Yangmin; Wang Liping; Wang Hong; Xu Ying; Yao Side

    2006-01-01

    The purpose of this study was to lay a foundation on generation mechanisms and removal method of off-odor of irradiated meat products. Vacuum-package and refrigerated raw pork samples were irradiated with 60 Co γ-rays. Off-odor volatiles from the irradiated pork samples were taken in by a vacuum system and were collected by a cooled vial in liquid nitrogen. At the same time, the source of off-odor generation was investigated. Main compositions of off-odor volatiles of the irradiated pork were analyzed with gas chromatograph mass spectrometry (GC-MS). The results showed that main compositions of the off-odor volatiles were dimethyl disulfide, dimethyl sulfide, dimethyl trisulfide, methanethiol and S-methyl thioacetate, and the off-odor volatiles came from sulfide-containing amino acid and thiamin of the irradiated pork. Sulfide-containing compounds increased with the dose in the range of 0-3 kGy, and decreased with the refrigeration time, but changed from different kinds of the package. The non-irradiated samples, however, contained just a little sulfide-containing compounds of dimethyl sulfide and vangardbt. (authors)

  6. Differential specificity in the glomerular response profiles for alicyclic, bicyclic and heterocyclic odorants

    Science.gov (United States)

    Johnson, Brett A.; Xu, Zhe; Pancoast, Paige; Kwok, Jennifer; Ong, Joan; Leon, Michael

    2008-01-01

    As part of our ongoing effort to relate stimulus to response in the olfactory system, we tested the hypothesis that the unique chemical structures and odors of various cyclic odorants would be associated with unique spatial response patterns in the glomerular layer of the rat olfactory bulb. To this end, rats were exposed to sets of odorants including monocyclic hydrocarbons, bicyclic compounds, and various heterocyclic structures containing oxygen or nitrogen in the ring. Relative activity across the entire layer was assessed by mapping uptake of 2-deoxyglucose into anatomically standardized data matrices. Whereas monocyclic hydrocarbons evoked patterns similar to those evoked by open-chained hydrocarbon odorants, a set of bicyclic compounds with structures and odors similar to camphor evoked uptake in paired ventral domains not previously associated with any other odorant chemical structures. Despite their unique odors as judged by humans, heterocyclic odorants either evoked uptake in previously characterized areas corresponding to their functional groups or stimulated weak or patchy patterns involving isolated glomeruli. While the patchiness of the patterns may be partly related to the rigidity of the compounds, which would be expected to restrict their interactions to only a few receptors, the weakness of the patterns suggests the possibility of species-specific odorant representations. We conclude that whereas some of the novel cyclic structures indeed were represented by unique patterns in the rat bulb, other unique structures were poorly represented, even when they evoked intense and unique odors in humans. PMID:16958095

  7. Ghrelin, leptin and adiponectin as possible predictors of the hedonic value of odors.

    Science.gov (United States)

    Trellakis, Sokratis; Tagay, Sefik; Fischer, Cornelia; Rydleuskaya, Alena; Scherag, André; Bruderek, Kirsten; Schlegl, Sandra; Greve, Jens; Canbay, Ali E; Lang, Stephan; Brandau, Sven

    2011-02-25

    Several lines of evidence point to a close relationship between the hormones of energy homeostasis and the olfactory system. Examples are the localization of leptin and adiponectin receptors in the olfactory system or increased activation of brain regions related to the palatability and the hedonic value of food in response to food pictures after application of ghrelin. In this preliminary study, we tested in 31 subjects (17 male and 14 female) if and to what extent the peripheral blood concentrations of "satiety" hormones, such as leptin, adiponectin, and ghrelin (acyl and total), are correlated with the self-ratings of odor pleasantness and with the objective olfactory and gustatory ability. The hedonic values of some odors were found to be differently rated between donors depending on gender and body weight. The concentrations of leptin, adiponectin and total ghrelin were significantly associated with the hedonic value of pepper black oil, but failed to show significant correlations for 5 other odors tested. Except for a significant association between leptin and odor identification, hormone concentrations were not linked to the abilities of smell and taste. Peripheral adipokines and gut hormones may alter the perception and pleasantness of specific odors, presumably either directly through their receptors in the olfactory system or indirectly through central interfaces between the regulation systems of olfaction, appetite control, memory and motivation. Copyright © 2010 Elsevier B.V. All rights reserved.

  8. Antifouling Cellulose Hybrid Biomembrane for Effective Oil/Water Separation.

    Science.gov (United States)

    Kollarigowda, Ravichandran H; Abraham, Sinoj; Montemagno, Carlo D

    2017-09-06

    Oil/water separation has been of great interest worldwide because of the increasingly serious environmental pollution caused by the abundant discharge of industrial wastewater, oil spill accidents, and odors. Here, we describe simple and economical superhydrophobic hybrid membranes for effective oil/water separation. Eco-friendly, antifouling membranes were fabricated for oil/water separation, waste particle filtration, the blocking of thiol-based odor materials, etc., by using a cellulose membrane (CM) filter. The CM was modified from its original superhydrophilic nature into a superhydrophobic surface via a reversible addition-fragmentation chain transfer technique. The block copolymer poly{[3-(trimethoxysilyl)propyl acrylate]-block-myrcene} was synthesized using a "grafting-from" approach on the CM. The surface contact angle that we obtained was >160°, and absorption tests of several organic contaminants (oils and solvents) exhibited superior levels of extractive activity and excellent reusability. These properties rendered this membrane a promising surface for oil/water separation. Interestingly, myrcene blocks thiol (through "-ene-" chemistry) contaminants, thereby bestowing a pleasant odor to polluted water by acting as an antifouling material. We exploited the structural properties of cellulose networks and simple chemical manipulations to fabricate an original material that proved to be effective in separating water from organic and nano/microparticulate contaminants. These characteristics allowed our material to effectively separate water from oily/particulate phases as well as embed antifouling materials for water purification, thus making it an appropriate absorber for chemical processes and environmental protection.

  9. Influence of Body Odors and Gender on Perceived Genital Arousal.

    Science.gov (United States)

    Alves-Oliveira, Patrícia; Carvalho, Joana; Ferreira, Jacqueline; Alho, Laura; Nobre, Pedro; Olsson, Mats J; Soares, Sandra C

    2018-04-01

    Olfaction is often linked to mating behavior in nonhumans. Additionally, studies in mating behavior have shown that women seem to be more affected by odor cues than men. However, the relationship between odor cues and sexual response-specifically, sexual arousal-has not been studied yet. The aim of this study was to evaluate the impact of the exposure to human body odors (from individuals of the opposite gender) on perceived genital arousal, while these were presented concomitantly to sexually explicit video clips. Eighty university students (40 women) rated their perceived genital arousal (perceived degree of erection/genital lubrication) in response to an audiovisual sexual stimulus, while simultaneously exposed to a body odor from an opposite-gender donor or no odor. Participants also rated each odor sample's (body odor and no odor) perceived pleasantness, intensity, and familiarity. Findings indicated that odor condition had an effect on women's (but not men's) perceived genital arousal, with women showing higher levels of perceived genital arousal in the no odor condition. Also, results showed that women rated body odors as less pleasant than no odor. Notwithstanding, the odor ratings do not seem to explain the association between body odor and perceived genital arousal. The current results support the hypothesis that women, rather than men, are sensitive to odors in the context of sexual response. The findings of this study have relevance for the understanding of human sexuality with respect to chemosensory communication.

  10. Friends and foes from an ant brain's point of view--neuronal correlates of colony odors in a social insect.

    Science.gov (United States)

    Brandstaetter, Andreas Simon; Rössler, Wolfgang; Kleineidam, Christoph Johannes

    2011-01-01

    Successful cooperation depends on reliable identification of friends and foes. Social insects discriminate colony members (nestmates/friends) from foreign workers (non-nestmates/foes) by colony-specific, multi-component colony odors. Traditionally, complex processing in the brain has been regarded as crucial for colony recognition. Odor information is represented as spatial patterns of activity and processed in the primary olfactory neuropile, the antennal lobe (AL) of insects, which is analogous to the vertebrate olfactory bulb. Correlative evidence indicates that the spatial activity patterns reflect odor-quality, i.e., how an odor is perceived. For colony odors, alternatively, a sensory filter in the peripheral nervous system was suggested, causing specific anosmia to nestmate colony odors. Here, we investigate neuronal correlates of colony odors in the brain of a social insect to directly test whether they are anosmic to nestmate colony odors and whether spatial activity patterns in the AL can predict how odor qualities like "friend" and "foe" are attributed to colony odors. Using ant dummies that mimic natural conditions, we presented colony odors and investigated their neuronal representation in the ant Camponotus floridanus. Nestmate and non-nestmate colony odors elicited neuronal activity: In the periphery, we recorded sensory responses of olfactory receptor neurons (electroantennography), and in the brain, we measured colony odor specific spatial activity patterns in the AL (calcium imaging). Surprisingly, upon repeated stimulation with the same colony odor, spatial activity patterns were variable, and as variable as activity patterns elicited by different colony odors. Ants are not anosmic to nestmate colony odors. However, spatial activity patterns in the AL alone do not provide sufficient information for colony odor discrimination and this finding challenges the current notion of how odor quality is coded. Our result illustrates the enormous challenge

  11. Honey bee odorant-binding protein 14: effects on thermal stability upon odorant binding revealed by FT-IR spectroscopy and CD measurements.

    Science.gov (United States)

    Schwaighofer, Andreas; Kotlowski, Caroline; Araman, Can; Chu, Nam; Mastrogiacomo, Rosa; Becker, Christian; Pelosi, Paolo; Knoll, Wolfgang; Larisika, Melanie; Nowak, Christoph

    2014-03-01

    In the present work, we study the effect of odorant binding on the thermal stability of honey bee (Apis mellifera L.) odorant-binding protein 14. Thermal denaturation of the protein in the absence and presence of different odorant molecules was monitored by Fourier transform infrared spectroscopy (FT-IR) and circular dichroism (CD). FT-IR spectra show characteristic bands for intermolecular aggregation through the formation of intermolecular β-sheets during the heating process. Transition temperatures in the FT-IR spectra were evaluated using moving-window 2D correlation maps and confirmed by CD measurements. The obtained results reveal an increase of the denaturation temperature of the protein when bound to an odorant molecule. We could also discriminate between high- and low-affinity odorants by determining transition temperatures, as demonstrated independently by the two applied methodologies. The increased thermal stability in the presence of ligands is attributed to a stabilizing effect of non-covalent interactions between odorant-binding protein 14 and the odorant molecule.

  12. Red junglefowl have individual body odors

    OpenAIRE

    Karlsson, Anna-Carin; Jensen, Per; Elgland, Mathias; Laur, Katriann; Fyrner, Timmy; Konradsson, Peter; Laska, Matthias

    2010-01-01

    Olfaction may play an important role in regulating bird behavior, and has been suggested to be involved in feather-pecking. We investigated possible differences in the body odors of red junglefowl females by using an automated olfactometer which assessed the ability of trained mice to discriminate between the odors of uropygial gland secretions (the main carrier of potential individual odors in chickens) of six feather-pecked and six non-pecked birds. All mice were clearly able to discriminat...

  13. Identification of pleasant, neutral, and unpleasant odors in schizophrenia.

    Science.gov (United States)

    Kamath, Vidyulata; Turetsky, Bruce I; Moberg, Paul J

    2011-05-15

    Recent work on odor hedonics in schizophrenia has indicated that patients display abnormalities in hedonic judgments of odors in comparison to healthy comparison participants. In the current study, identification accuracy for pleasant, neutral, and unpleasant odors in individuals with schizophrenia and healthy controls was examined. Thirty-three schizophrenia patients (63% male) and thirty-one healthy volunteers (65% male) were recruited. The groups were well matched on age, sex, and smoking status. Participants were administered the University of Pennsylvania Smell Identification Test, which was subsequently divided into 16 pleasant, 15 neutral, and 9 unpleasant items. Analysis of identification z-scores for pleasant, neutral, and unpleasant odors revealed a significant diagnosis by valence interaction. Post-hoc analysis revealed that schizophrenia participants made more identification errors on pleasant and neutral odors compared to healthy controls, with no differences observed for unpleasant odors. No effect was seen for sex. The findings from the current investigation suggest that odor identification accuracy in patients is influenced by odor valence. This pattern of results parallels a growing body of literature indicating that patients display aberrant pleasantness ratings for pleasant odors and highlights the need for additional research on the influence of odor valence on olfactory identification performance in individuals with schizophrenia. Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. Enhancement of Retronasal Odors by Taste

    OpenAIRE

    Green, Barry G.; Nachtigal, Danielle; Hammond, Samuel; Lim, Juyun

    2011-01-01

    Psychophysical studies of interactions between retronasal olfaction and taste have focused most often on the enhancement of tastes by odors, which has been attributed primarily to a response bias (i.e., halo dumping). Based upon preliminary evidence that retronasal odors could also be enhanced by taste, the present study measured both forms of enhancement using appropriate response categories. In the first experiment, subjects rated taste (“sweet,” “sour,” “salty,” and “bitter”) and odor (“ot...

  15. Odor and odorous chemical emissions from dairy and swine facilities: Part 5-Simultaneous chemical and sensory analysis with Gas Chromatography - Mass Spectrometry - Olfactometry

    Science.gov (United States)

    Simultaneous chemical and sensory analyses using gas chromatography-mass spectrometry-olfactometry (GC-MS-O) for air samples collected at barn exhaust fans were used for quantification and ranking of odor impact of target odorous gases. Fifteen target odorous VOCs (odorants) were selected. Air sampl...

  16. Blue petrels recognize the odor of their egg.

    Science.gov (United States)

    Leclaire, Sarah; Bourret, Vincent; Bonadonna, Francesco

    2017-09-01

    Most studies on avian olfactory communication have focused on mate choice, and the importance of olfaction in subsequent nesting stages has been poorly explored. In particular, the role of olfactory cues in egg recognition has received little attention, despite eggs potentially being spread with parental odorous secretions known to elicit individual discrimination. Here, we used behavioral choice tests to determine whether female blue petrels ( Halobaena caerulea ) can discriminate the odor of their own egg from the odor of a conspecific egg. Females preferentially approached the odor of their own egg, suggesting that blue petrels can recognize their own egg using odor cues. This finding raises the question of the adaptive value of this mechanism, and may inspire further research on odor-based egg discrimination in species suffering brood parasitism. © 2017. Published by The Company of Biologists Ltd.

  17. Inactivation of Medial Prefrontal Cortex or Acute Stress Impairs Odor Span in Rats

    Science.gov (United States)

    Davies, Don A.; Molder, Joel J.; Greba, Quentin; Howland, John G.

    2013-01-01

    The capacity of working memory is limited and is altered in brain disorders including schizophrenia. In rodent working memory tasks, capacity is typically not measured (at least not explicitly). One task that does measure working memory capacity is the odor span task (OST) developed by Dudchenko and colleagues. In separate experiments, the effects…

  18. Evaluation of Odor-Reducing Commercial Products for Animal Waste

    OpenAIRE

    Shukla, Shuchi S.

    1997-01-01

    Six odor-reducing commercial products were tested for their efficacy in reducing odors from dairy and swine wastes. A sensory panel method was utilized for odor evaluations, in which the panel played an important part. Comparisons between products were made for agitated and unagitated conditions and effect of storage time (three weeks in which experiments were performed). Cotton pieces tied to the mouth of the sample jars were useful in absorbing the odors. Odor-treated jars were observed and...

  19. The Mouse Solitary Odorant Receptor Gene Promoters as Models for the Study of Odorant Receptor Gene Choice.

    Directory of Open Access Journals (Sweden)

    Andrea Degl'Innocenti

    Full Text Available In vertebrates, several anatomical regions located within the nasal cavity mediate olfaction. Among these, the main olfactory epithelium detects most conventional odorants. Olfactory sensory neurons, provided with cilia exposed to the air, detect volatile chemicals via an extremely large family of seven-transmembrane chemoreceptors named odorant receptors. Their genes are expressed in a monogenic and monoallelic fashion: a single allele of a single odorant receptor gene is transcribed in a given mature neuron, through a still uncharacterized molecular mechanism known as odorant receptor gene choice.Odorant receptor genes are typically arranged in genomic clusters, but a few are isolated (we call them solitary from the others within a region broader than 1 Mb upstream and downstream with respect to their transcript's coordinates. The study of clustered genes is problematic, because of redundancy and ambiguities in their regulatory elements: we propose to use the solitary genes as simplified models to understand odorant receptor gene choice.Here we define number and identity of the solitary genes in the mouse genome (C57BL/6J, and assess the conservation of the solitary status in some mammalian orthologs. Furthermore, we locate their putative promoters, predict their homeodomain binding sites (commonly present in the promoters of odorant receptor genes and compare candidate promoter sequences with those of wild-caught mice. We also provide expression data from histological sections.In the mouse genome there are eight intact solitary genes: Olfr19 (M12, Olfr49, Olfr266, Olfr267, Olfr370, Olfr371, Olfr466, Olfr1402; five are conserved as solitary in rat. These genes are all expressed in the main olfactory epithelium of three-day-old mice. The C57BL/6J candidate promoter of Olfr370 has considerably varied compared to its wild-type counterpart. Within the putative promoter for Olfr266 a homeodomain binding site is predicted. As a whole, our findings

  20. AMisfit Theory of Spontaneous Conscious Odor Perception (MITSCOP: reflections on the role and function of odor memory in everyday life.

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    Egon P Köster

    2014-02-01

    Full Text Available Our senses have developed as an answer to the world we live in (Gibson, 1966 and so have the forms of memory that accompany them. All senses serve different purposes and do so in different ways. In vision, where orientation and object recognition are important, memory is strongly linked to identification. In olfaction, the guardian of vital functions such as breathing and food ingestion, perhaps the most important (and least noticed and researched role of odor memory is to help us not to notice the well-known odors or flavors in our everyday surroundings, but to react immediately to the unexpected ones. At the same time it provides us with a feeling of safety when our expectancies are met. All this happens without any smelling intention or conscious knowledge of our expectations. Identification by odor naming is not involved in this and people are notoriously bad at it. Odors are usually best identified via the episodic memory of the situation in which they once occurred. Spontaneous conscious odor perception normally only occurs in situations where attention is demanded, either because the inhaled air or the food smell is particularly good or particularly bad and people search for its source or because people want to actively enjoy the healthiness and pleasantness of their surroundings or food. Odor memory is concerned with novelty detection rather than with recollection of odors. In this paper, these points are illustrated with experimental results and their consequences for doing ecologically valid odor memory research are drawn. Furthermore, suggestions for ecologically valid research on everyday odor memory and some illustrative examples are given.

  1. Complex Odor from Plants under Attack: Herbivore's Enemies React to the Whole, Not Its Parts

    Science.gov (United States)

    van Wijk, Michiel; de Bruijn, Paulien J. A.; Sabelis, Maurice W.

    2011-01-01

    Background Insect herbivory induces plant odors that attract herbivores' natural enemies. Assuming this attraction emerges from individual compounds, genetic control over odor emission of crops may provide a rationale for manipulating the distribution of predators used for pest control. However, studies on odor perception in vertebrates and invertebrates suggest that olfactory information processing of mixtures results in odor percepts that are a synthetic whole and not a set of components that could function as recognizable individual attractants. Here, we ask if predators respond to herbivore-induced attractants in odor mixtures or to odor mixture as a whole. Methodology/Principal Findings We studied a system consisting of Lima bean, the herbivorous mite Tetranychus urticae and the predatory mite Phytoseiulus persimilis. We found that four herbivore-induced bean volatiles are not attractive in pure form while a fifth, methyl salicylate (MeSA), is. Several reduced mixtures deficient in one component compared to the full spider-mite induced blend were not attractive despite the presence of MeSA indicating that the predators cannot detect this component in these odor mixtures. A mixture of all five HIPV is most attractive, when offered together with the non-induced odor of Lima bean. Odors that elicit no response in their pure form were essential components of the attractive mixture. Conclusions/Significance We conclude that the predatory mites perceive odors as a synthetic whole and that the hypothesis that predatory mites recognize attractive HIPV in odor mixtures is unsupported. PMID:21765908

  2. Complex odor from plants under attack: herbivore's enemies react to the whole, not its parts.

    Directory of Open Access Journals (Sweden)

    Michiel van Wijk

    Full Text Available Insect herbivory induces plant odors that attract herbivores' natural enemies. Assuming this attraction emerges from individual compounds, genetic control over odor emission of crops may provide a rationale for manipulating the distribution of predators used for pest control. However, studies on odor perception in vertebrates and invertebrates suggest that olfactory information processing of mixtures results in odor percepts that are a synthetic whole and not a set of components that could function as recognizable individual attractants. Here, we ask if predators respond to herbivore-induced attractants in odor mixtures or to odor mixture as a whole.We studied a system consisting of Lima bean, the herbivorous mite Tetranychus urticae and the predatory mite Phytoseiulus persimilis. We found that four herbivore-induced bean volatiles are not attractive in pure form while a fifth, methyl salicylate (MeSA, is. Several reduced mixtures deficient in one component compared to the full spider-mite induced blend were not attractive despite the presence of MeSA indicating that the predators cannot detect this component in these odor mixtures. A mixture of all five HIPV is most attractive, when offered together with the non-induced odor of Lima bean. Odors that elicit no response in their pure form were essential components of the attractive mixture.We conclude that the predatory mites perceive odors as a synthetic whole and that the hypothesis that predatory mites recognize attractive HIPV in odor mixtures is unsupported.

  3. Friends and Foes from an Ant Brain's Point of View – Neuronal Correlates of Colony Odors in a Social Insect

    Science.gov (United States)

    Brandstaetter, Andreas Simon; Rössler, Wolfgang; Kleineidam, Christoph Johannes

    2011-01-01

    Background Successful cooperation depends on reliable identification of friends and foes. Social insects discriminate colony members (nestmates/friends) from foreign workers (non-nestmates/foes) by colony-specific, multi-component colony odors. Traditionally, complex processing in the brain has been regarded as crucial for colony recognition. Odor information is represented as spatial patterns of activity and processed in the primary olfactory neuropile, the antennal lobe (AL) of insects, which is analogous to the vertebrate olfactory bulb. Correlative evidence indicates that the spatial activity patterns reflect odor-quality, i.e., how an odor is perceived. For colony odors, alternatively, a sensory filter in the peripheral nervous system was suggested, causing specific anosmia to nestmate colony odors. Here, we investigate neuronal correlates of colony odors in the brain of a social insect to directly test whether they are anosmic to nestmate colony odors and whether spatial activity patterns in the AL can predict how odor qualities like “friend” and “foe” are attributed to colony odors. Methodology/Principal Findings Using ant dummies that mimic natural conditions, we presented colony odors and investigated their neuronal representation in the ant Camponotus floridanus. Nestmate and non-nestmate colony odors elicited neuronal activity: In the periphery, we recorded sensory responses of olfactory receptor neurons (electroantennography), and in the brain, we measured colony odor specific spatial activity patterns in the AL (calcium imaging). Surprisingly, upon repeated stimulation with the same colony odor, spatial activity patterns were variable, and as variable as activity patterns elicited by different colony odors. Conclusions Ants are not anosmic to nestmate colony odors. However, spatial activity patterns in the AL alone do not provide sufficient information for colony odor discrimination and this finding challenges the current notion of how odor

  4. Odor-Specific Habituation Arises from Interaction of Afferent Synaptic Adaptation and Intrinsic Synaptic Potentiation in Olfactory Cortex

    Science.gov (United States)

    Linster, Christiane; Menon, Alka V.; Singh, Christopher Y.; Wilson, Donald A.

    2009-01-01

    Segmentation of target odorants from background odorants is a fundamental computational requirement for the olfactory system and is thought to be behaviorally mediated by olfactory habituation memory. Data from our laboratory have shown that odor-specific adaptation in piriform neurons, mediated at least partially by synaptic adaptation between…

  5. Body odor based personality judgments: The effect of fragranced cosmetics

    Directory of Open Access Journals (Sweden)

    Agnieszka eSorokowska

    2016-04-01

    Full Text Available People can accurately assess various personality traits of others based on body odor alone. Previous studies have shown that correlations between odor ratings and self-assessed personality dimensions are evident for assessments of neuroticism and dominance. Here, we tested differences between assessments based on natural body odor alone, without the use of cosmetics and assessments based on the body odor of people who were allowed to use cosmetics following their daily routine. Sixty-seven female observers assessed samples of odors from 113 odor donors (each odor donor provided two samples – one with and one without cosmetic use; the donors provided their personality ratings, and the raters judged personality characteristics of the donors based on the provided odor samples. Correlations between observers’ ratings and self-rated neuroticism were stronger when raters assessed body odor in the natural body odor condition (natural BO condition; rs = .20 than in the cosmetics use condition (BO+cosmetics condition; rs = .15. Ratings of dominance significantly predicted self-assessed dominance in both conditions (rs = .34 for natural BO and rs = .21 for BO+cosmetics, whereas ratings of extraversion did not predict self-assessed extraversion in either condition. In addition, ratings of body odor attractiveness and pleasantness were significantly lower in natural BO condition than in BO+cosmetics condition, although the intensity of donors’ body odors was similar under both conditions. Our findings suggest that although olfaction seems to contribute to accurate first impression judgments of certain personality traits, cosmetic use can affect assessments of others based on body odor.

  6. Effect of fragrance use on discrimination of individual body odor

    Science.gov (United States)

    Allen, Caroline; Havlíček, Jan; Roberts, S. Craig

    2015-01-01

    Previous research suggests that artificial fragrances may be chosen to complement or enhance an individual’s body odor, rather than simply masking it, and that this may create an odor blend with an emergent quality that is perceptually distinguishable from body odor or fragrance alone. From this, it can be predicted that a new emergent odor might be more easily identified than an individual’s body odor in isolation. We used a triangle test paradigm to assess whether fragrance affects people’s ability to distinguish between individual odors. Six male and six female donors provided axillary odor samples in three conditions (without fragrance, wearing their own fragrance, and wearing an assigned fragrance). In total, 296 female and 131 male participants selected the odd one from three odor samples (two from one donor, one from another; both of the same sex). We found that participants could discriminate between the odors at above chance levels in all three odor conditions. Olfactory identification ability (measured using Sniffin’ Sticks) positively predicted discrimination performance, and sex differences in performance were also observed, with female raters being correct more often than men. Success rates were also higher for odors of male donors. Additionally, while performance was above chance in all conditions, individual odor discrimination varied across the three conditions. Discrimination rate was significantly higher in the “no fragrance” condition than either of the fragranced conditions. Importantly, however, discrimination rate was also significantly higher in the “own fragrance” condition than the “assigned fragrance” condition, suggesting that naturally occurring variance in body odor is more preserved when blended with fragrances that people choose for themselves, compared with other fragrances. Our data are consistent with the idea that fragrance choices are influenced by fragrance interactions with an individual’s own body odor

  7. Electronic Nose Odor Classification with Advanced Decision Tree Structures

    Directory of Open Access Journals (Sweden)

    S. Guney

    2013-09-01

    Full Text Available Electronic nose (e-nose is an electronic device which can measure chemical compounds in air and consequently classify different odors. In this paper, an e-nose device consisting of 8 different gas sensors was designed and constructed. Using this device, 104 different experiments involving 11 different odor classes (moth, angelica root, rose, mint, polis, lemon, rotten egg, egg, garlic, grass, and acetone were performed. The main contribution of this paper is the finding that using the chemical domain knowledge it is possible to train an accurate odor classification system. The domain knowledge about chemical compounds is represented by a decision tree whose nodes are composed of classifiers such as Support Vector Machines and k-Nearest Neighbor. The overall accuracy achieved with the proposed algorithm and the constructed e-nose device was 97.18 %. Training and testing data sets used in this paper are published online.

  8. A specialized odor memory buffer in primary olfactory cortex.

    Science.gov (United States)

    Zelano, Christina; Montag, Jessica; Khan, Rehan; Sobel, Noam

    2009-01-01

    The neural substrates of olfactory working memory are unknown. We addressed the questions of whether olfactory working memory involves a verbal representation of the odor, or a sensory image of the odor, or both, and the location of the neural substrates of these processes. We used functional magnetic resonance imaging to measure activity in the brains of subjects who were remembering either nameable or unnameable odorants. We found a double dissociation whereby remembering nameable odorants was reflected in sustained activity in prefrontal language areas, and remembering unnameable odorants was reflected in sustained activity in primary olfactory cortex. These findings suggest a novel dedicated mechanism in primary olfactory cortex, where odor information is maintained in temporary storage to subserve ongoing tasks.

  9. Fancy citrus, feel good: Positive judgment of citrus odor, but not the odor itself, is associated with elevated mood during experienced helplessness

    Directory of Open Access Journals (Sweden)

    Matthias eHoenen

    2016-02-01

    Full Text Available Aromatherapy claims that citrus essential oils exert mood lifting effects. Controlled studies, however, have yielded inconsistent results. Notably, studies so far did not control for odor pleasantness, although pleasantness is a critical determinant of emotional responses to odors. This study investigates mood lifting effects of d-(+-limonene, the most prominent substance in citrus essential oils, with respect to odor quality judgments.Negative mood was induced within 78 participants using a helplessness paradigm (unsolvable social discrimination task. During this task, participants were continuously (mean duration: 19.5 min exposed to d-(+-limonene (n = 25, vanillin (n = 26, or diethyl phthalate (n = 27. Participants described their mood (Self-Assessment-Manikin, basic emotion ratings and judged the odors’ quality (intensity, pleasantness, unpleasantness, familiarity prior to and following the helplessness induction. The participants were in a less positive mood after the helplessness induction (p < .001, irrespective of the odor condition. Still, the more pleasant the participants judged the odors, the less effective the helplessness induction was in reducing happiness (p = .019.The results show no odor specific mood lifting effect of d-(+-limonene, but indicate a positive effect of odor pleasantness on mood. The study highlights the necessity to evaluate odor judgments in aromatherapy research.

  10. Walking patterns induced by learned odors in the honeybee, Apis mellifera L.

    Science.gov (United States)

    Yamashita, Toshiya; Haupt, S Shuichi; Ikeno, Hidetoshi; Ai, Hiroyuki

    2016-01-01

    The odor localization strategy induced by odors learned via differential conditioning of the proboscis extension response was investigated in honeybees. In response to reward-associated but not non-reward-associated odors, learners walked longer paths than non-learners and control bees. When orange odor reward association was learned, the path length and the body turn angles were small during odor stimulation and greatly increased after stimulation ceased. In response to orange odor, bees walked locally with alternate left and right turns during odor stimulation to search for the reward-associated odor source. After odor stimulation, bees walked long paths with large turn angles to explore the odor plume. For clove odor, learning-related modulations of locomotion were less pronounced, presumably due to a spontaneous preference for orange in the tested population of bees. This study is the first to describe how an odor-reward association modulates odor-induced walking in bees. © 2016. Published by The Company of Biologists Ltd.

  11. Odor preference and olfactory memory are impaired in Olfaxin-deficient mice.

    Science.gov (United States)

    Islam, Saiful; Ueda, Masashi; Nishida, Emika; Wang, Miao-Xing; Osawa, Masatake; Lee, Dongsoo; Itoh, Masanori; Nakagawa, Kiyomi; Tana; Nakagawa, Toshiyuki

    2018-06-01

    Olfaxin, which is a BNIP2 and Cdc42GAP homology (BCH) domain-containing protein, is predominantly expressed in mitral and tufted (M/T) cells in the olfactory bulb (OB). Olfaxin and Caytaxin, which share 56.3% amino acid identity, are similar in their glutamatergic terminal localization, kidney-type glutaminase (KGA) interaction, and caspase-3 substrate. Although the deletion of Caytaxin protein causes human Cayman ataxia and ataxia in the mutant mouse, the function of Olfaxin is largely unknown. In this study, we generated Prune2 gene mutant mice (Prune2 Ex16-/- ; knock out [KO] mice) using the CRISPR/Cas9 system, during which the exon 16 containing start codon of Olfaxin mRNA was deleted. Exon 16 has 80 nucleotides and is contained in four of five Prune2 isoforms, including PRUNE2, BMCC1, BNIPXL, and Olfaxin/BMCC1s. The levels of Olfaxin mRNA and Olfaxin protein in the OB and piriform cortex of KO mice significantly decreased. Although Prune2 mRNA also significantly decreased in the spinal cord, the gross anatomy of the spinal cord and dorsal root ganglion (DRG) was intact. Further, disturbance of the sensory and motor system was not observed in KO mice. Therefore, in the current study, we examined the role of Olfaxin in the olfactory system where PRUNE2, BMCC1, and BNIPXL are scarcely expressed. Odor preference was impaired in KO mice using opposite-sex urinary scents as well as a non-social odor stimulus (almond). Results of the odor-aversion test demonstrated that odor-associative learning was disrupted in KO mice. Moreover, the NMDAR2A/NMDAR2B subunits switch in the piriform cortex was not observed in KO mice. These results indicated that Olfaxin may play a critical role in odor preference and olfactory memory. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Neuropeptide Y enhances olfactory mucosa responses to odorant in hungry rats.

    Science.gov (United States)

    Negroni, Julia; Meunier, Nicolas; Monnerie, Régine; Salesse, Roland; Baly, Christine; Caillol, Monique; Congar, Patrice

    2012-01-01

    Neuropeptide Y (NPY) plays an important role in regulating appetite and hunger in vertebrates. In the hypothalamus, NPY stimulates food intake under the control of the nutritional status. Previous studies have shown the presence of NPY and receptors in rodent olfactory system, and suggested a neuroproliferative role. Interestingly, NPY was also shown to directly modulate olfactory responses evoked by a food-related odorant in hungry axolotls. We have recently demonstrated that another nutritional cue, insulin, modulates the odorant responses of the rat olfactory mucosa (OM). Therefore, the aim of the present study was to investigate the potential effect of NPY on rat OM responses to odorants, in relation to the animal's nutritional state. We measured the potential NPY modulation of OM responses to odorant, using electro-olfactogram (EOG) recordings, in fed and fasted adult rats. NPY application significantly and transiently increased EOG amplitudes in fasted but not in fed rats. The effects of specific NPY-receptor agonists were similarly quantified, showing that NPY operated mainly through Y1 receptors. These receptors appeared as heterogeneously expressed by olfactory neurons in the OM, and western blot analysis showed that they were overexpressed in fasted rats. These data provide the first evidence that NPY modulates the initial events of odorant detection in the rat OM. Because this modulation depends on the nutritional status of the animal, and is ascribed to NPY, the most potent orexigenic peptide in the central nervous system, it evidences a strong supplementary physiological link between olfaction and nutritional processes.

  13. Odors as effective retrieval cues for stressful episodes.

    Science.gov (United States)

    Wiemers, Uta S; Sauvage, Magdalena M; Wolf, Oliver T

    2014-07-01

    Olfactory information seems to play a special role in memory due to the fast and direct processing of olfactory information in limbic areas like the amygdala and the hippocampus. This has led to the assumption that odors can serve as effective retrieval cues for autobiographic memories, especially emotional memories. The current study sought to investigate whether an olfactory cue can serve as an effective retrieval cue for memories of a stressful episode. A total of 95 participants were exposed to a psychosocial stressor or a well matching but not stressful control condition. During both conditions were visual objects present, either bound to the situation (central objects) or not (peripheral objects). Additionally, an ambient odor was present during both conditions. The next day, participants engaged in an unexpected object recognition task either under the influence of the same odor as was present during encoding (congruent odor) or another odor (non-congruent odor). Results show that stressed participants show a better memory for all objects and especially for central visual objects if recognition took place under influence of the congruent odor. An olfactory cue thus indeed seems to be an effective retrieval cue for stressful memories. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Emotion experienced during encoding enhances odor retrieval cue effectiveness.

    Science.gov (United States)

    Herz, R S

    1997-01-01

    Emotional potentiation may be a key variable in the formation of odor-associated memory. Two experiments were conducted in which a distinctive ambient odor was present or absent during encoding and retrieval sessions and subjects were in an anxious or neutral mood during encoding. Subjects' mood at retrieval was not manipulated. The laboratory mood induction used in Experiment 1 suggested that anxiety might increase the effectiveness of an odor retrieval cue. This trend was confirmed in Experiment 2 by capturing a naturally stressful situation. Subjects who had an ambient odor cue available and were in a preexam state during encoding recalled more words than subjects in any other group. These data are evidence that heightened emotion experienced during encoding with an ambient odor can enhance the effectiveness of an odor as a cue to memory.

  15. Study on off-odor volatiles of irradiated packaged raw pork

    International Nuclear Information System (INIS)

    Lin Ruotai; Geng Shengrong; Liu Yangmin

    2008-01-01

    Analysing the compositions of off-odor volatiles in irradiated refrigerated vacuum-packaged pork and research on its origin. First, the off-odor volatiles were collected by a cooled via in liquid nitrogen, then the main composition of off-odor volatiles were analyzed by gas chromatograph mass spectrometry (GC-MS). The main composition of off-odor volatiles are dimethyl disulfide, dimethyl sulfide, dimethyl trisulfide, methanethiol and S-methyl thioacetate. The off-odor volatiles come from irradiated cystine, methionine and VB1. The main composition of off-odor volatiles are S-containing compounds from irradiated S-containing amino acid and VB1

  16. Odor concentration invariance by chemical ratio coding

    Directory of Open Access Journals (Sweden)

    Naoshige Uchida

    2008-08-01

    Full Text Available Many animal species rely on chemical signals to extract ecologically important information from the environment. Yet in natural conditions chemical signals will frequently undergo concentration changes that produce differences in both level and pattern of activation of olfactory receptor neurons. Thus, a central problem in olfactory processing is how the system is able to recognize the same stimulus across different concentrations. To signal species identity for mate recognition, some insects use the ratio of two components in a binary chemical mixture to produce a code that is invariant to dilution. Here, using psychophysical methods, we show that rats also classify binary odor mixtures according to the molar ratios of their components, spontaneously generalizing over at least a tenfold concentration range. These results indicate that extracting chemical ratio information is not restricted to pheromone signaling and suggest a general solution for concentration-invariant odor recognition by the mammalian olfactory system.

  17. Effect of fragrance use on discrimination of individual body odor

    Directory of Open Access Journals (Sweden)

    Caroline eAllen

    2015-08-01

    Full Text Available Previous research suggests that artificial fragrances may be chosen to complement or enhance an individual’s body odor, rather than simply masking it, and that this may create an odor blend with an emergent quality that is perceptually distinguishable from body odor or fragrance alone. From this, it can be predicted that a new emergent odor might be more easily identified than an individual’s body odor in isolation. We used a triangle test paradigm to assess whether fragrance affects people’s ability to distinguish between individual odors. Six male and six female donors provided axillary odor samples in three conditions (without fragrance, wearing their own fragrance, and wearing an assigned fragrance. In total, 296 female and 131 male participants selected the odd one out from three odor samples (two from one donor, one from another; both of the same sex. We found that participants could discriminate between the odors at above chance levels in all three odour conditions. Olfactory identification ability (measured using Sniffin’ Sticks positively predicted discrimination performance, and sex differences in performance were also observed, with female raters being correct more often than men. Success rates were also higher for odors of male donors. Additionally, while performance was above chance in all conditions, individual odor discrimination varied across the three conditions. Discrimination rate was significantly higher in the ‘no fragrance’ condition than either of the fragranced conditions. Importantly, however, discrimination rate was also significantly higher in the ‘own fragrance’ condition than the ‘assigned fragrance’ condition, suggesting that naturally occurring variance in body odor is more preserved when blended with fragrances that people choose for themselves, compared with other fragrances. Our data are consistent with the idea that fragrance choices are influenced by fragrance interactions with an

  18. Field Air Sampling and Simultaneous Chemical and Sensory Analysis of Livestock Odorants with Sorbent Tube GC-MS/Olfactometry

    International Nuclear Information System (INIS)

    Zhang Shicheng; Cai Lingshuang; Koziel, Jacek A.; Hoff, Steven; Clanton, Charles; Schmidt, David; Jacobson, Larry; Parker, David; Heber, Albert

    2009-01-01

    Characterization and quantification of livestock odorants is one of the most challenging analytical tasks because odor-causing gases are very reactive, polar and often present at very low concentrations in a complex matrix of less important or irrelevant gases. The objective of this research was to develop a novel analytical method for characterization of the livestock odorants including their odor character, odor intensity, and hedonic tone and to apply this method for quantitative analysis of the key odorants responsible for livestock odor. Sorbent tubes packed with Tenax TA were used for field sampling. The automated one-step thermal desorption module coupled with multidimensional gas chromatography-mass spectrometry/olfactometry system was used for simultaneous chemical and odor analysis. Fifteen odorous VOCs and semi-VOCs identified from different livestock species operations were quantified. Method detection limits ranges from 40 pg for skatole to 3590 pg for acetic acid. In addition, odor character, odor intensity and hedonic tone associated with each of the target odorants are also analyzed simultaneously. We found that the mass of each VOCs in the sample correlates well with the log stimulus intensity. All of the correlation coefficients (R 2 ) are greater than 0.74, and the top 10 correlation coefficients were greater than 0.90.

  19. Apolipoprotein e4 Is Associated with More Rapid Decline in Odor Identification than in Odor Threshold or Dementia Rating Scale Scores

    Science.gov (United States)

    Calhoun-Haney, R.; Murphy, C.

    2005-01-01

    Individuals with the apolipoprotein E e4 genetic risk factor for Alzheimer's disease (AD) show deficits in olfactory function. The purpose of the present study was to examine longitudinally odor identification (odor ID), odor threshold, picture identification, and global cognitive status in allele positive (e4+) and negative (e4-) persons.…

  20. Genetic and environmental influences on odor identification ability in the very old

    DEFF Research Database (Denmark)

    Doty, Richard L; Petersen, Inge; Mensah, Nii

    2011-01-01

    Odor identification ability and cognition were measured in a population-based cohort of 1,222 very old twins and singletons, including 91 centenarians. Heritability for identifying odors was low, in contrast to that for cognition. Common genes were found to contribute to both olfaction and cognit...... with age, likely reflecting adverse environmental influences on the smell system. (PsycINFO Database Record (c) 2011 APA, all rights reserved)....

  1. Rapid encoding and perception of novel odors in the rat.

    Directory of Open Access Journals (Sweden)

    Daniel W Wesson

    2008-04-01

    Full Text Available To gain insight into which parameters of neural activity are important in shaping the perception of odors, we combined a behavioral measure of odor perception with optical imaging of odor representations at the level of receptor neuron input to the rat olfactory bulb. Instead of the typical test of an animal's ability to discriminate two familiar odorants by exhibiting an operant response, we used a spontaneously expressed response to a novel odorant-exploratory sniffing-as a measure of odor perception. This assay allowed us to measure the speed with which rats perform spontaneous odor discriminations. With this paradigm, rats discriminated and began responding to a novel odorant in as little as 140 ms. This time is comparable to that measured in earlier studies using operant behavioral readouts after extensive training. In a subset of these trials, we simultaneously imaged receptor neuron input to the dorsal olfactory bulb with near-millisecond temporal resolution as the animal sampled and then responded to the novel odorant. The imaging data revealed that the bulk of the discrimination time can be attributed to the peripheral events underlying odorant detection: receptor input arrives at the olfactory bulb 100-150 ms after inhalation begins, leaving only 50-100 ms for central processing and response initiation. In most trials, odor discrimination had occurred even before the initial barrage of receptor neuron firing had ceased and before spatial maps of activity across glomeruli had fully developed. These results suggest a coding strategy in which the earliest-activated glomeruli play a major role in the initial perception of odor quality, and place constraints on coding and processing schemes based on simple changes in spike rate.

  2. Recognition of Bread Key Odorants by Using Polymer Coated QCMs

    Science.gov (United States)

    Nakai, Takashi; Kouno, Shinji; Hiruma, Naoya; Shuzo, Masaki; Delaunay, Jean-Jacques; Yamada, Ichiro

    Polyisobutylene (PIB) polymer and methylphenylsiloxane (25%) diphenylsiloxane (75%) copolymer (OV25) were coated on Quartz Crystal Microbalance (QCM) sensors and used in recognition of bread key odorants. Representative compounds of key roasty odorants of bread were taken as 3-acetylpyridine and benzaldehyde, and representative key fatty odorants were hexanal and (E)-2-nonenal. Both OV25- and PIB-coated QCM fabricated sensors could detect concentration as low as 0.9 ppm of 3-acetylpyridine and 1.2 ppm of (E)-2-nonenal. The sensitivity to 3-acetylpyridine of the OV25-coated QCM was about 1000 times higher than that of ethanol, the major interference compound in bread key odorant analysis. Further, the OV25-coated QCM response was 5-6 times and 2-3 times larger than that of the PIB-coated QCM when exposed to roasty odorants and to fatty odorants, respectively. The difference in sensitivity of the OV25- and PIB-coated QCMs we fabricated made possible to discriminate roasty from fatty odorants as was evidenced by the odor recognition map representing the frequency shifts of the OV25-coated QCM against the frequency shift of the PIB-coated QCM. In conclusion, we found that the combination of an OV25-coated QCM and a PIB-coated QCM was successful in discriminating roasty odorants from fatty odorants at the ppm level.

  3. Functional Neuronal Processing of Human Body Odors

    OpenAIRE

    Lundström, Johan N.; Olsson, Mats J.

    2010-01-01

    Body odors carry informational cues of great importance for individuals across a wide range of species, and signals hidden within the body odor cocktail are known to regulate several key behaviors in animals. For a long time, the notion that humans may be among these species has been dismissed. We now know, however, that each human has a unique odor signature that carries information related to his or her genetic makeup, as well as information about personal environmental variables, such as d...

  4. Postnatal odorant exposure induces peripheral olfactory plasticity at the cellular level

    OpenAIRE

    CADIOU , Hervé; AOUDE , Imad; Tazir , Bassim; Molinas , Adrien; Forbes Fenech , Claire; Meunier , Nicolas; Grosmaitre , Xavier

    2014-01-01

    Mammalian olfactory sensory neurons (OSNs) form the primary elements of the olfactory system. Inserted in the olfactory mucosa lining of the nasal cavity, they are exposed to the environment and their lifespan is brief. Several reports say that OSNs are regularly regenerated during the entire life and that odorant environment affects the olfactory epithelium. However, little is known about the impact of the odorant environment on OSNs at the cellular level and more precisely in the context of...

  5. Characterization of odor-active compounds in cooked meat of farmed obscure puffer (Takifugu obscurus using gas chromatography–mass spectrometry–olfactometry

    Directory of Open Access Journals (Sweden)

    Ning-Ping Tao

    2014-12-01

    Full Text Available The volatile and odor-active compounds in cooked meat of farmed obscure puffer (Takifugu obscurus were analyzed by gas chromatography–mass spectrometry–olfactometry (GC–MS–O. The volatile compounds were extracted by the simultaneous distillation–extraction (SDE method, then separated and identified by GC–MS. Odor-active compounds in the SDE extract were characterized by GC–MS–O. A total of 68 volatile compounds were found, including 23 aldehydes, 10 alcohols, nine ketones, 17 N- or S-containing compounds and aromatics, three acids, three alkanes, and three esters. Of these, 31 odor-active compounds were detected and identified. Trimethylamine (fishy, octanal (grassy, leafy, green, (E-2-octenal (roast, fatty, 1-octen-3-ol (fishy, fatty, mushroom, grassy, 2-ethyl-1-hexanethiol (cooked fish, (E,E-2,4-octadienal (cooked meat, sweet, 2-acetylthiazole (meaty, roast, nutty, sulfur, 2-acetylpyrrole (nutty, walnut, bread were identified as the key odorants in the cooked meat of farmed obscure puffer based on posterior intensity and time-intensity methods.

  6. What's that smell? An ecological approach to understanding preferences for familiar odors.

    Science.gov (United States)

    Schloss, Karen B; Goldberger, Carolyn S; Palmer, Stephen E; Levitan, Carmel A

    2015-01-01

    How do odor preferences arise? Following Palmer and Schloss's (2010, PNAS, 107, 8877-8882) ecological valence theory of color preferences, we propose that preference for an odor is determined by preferences for all objects and/or entities associated with that odor. The present results showed that preferences for familiar odors were strongly predicted by average preferences for all things associated with the odors (eg people liked the apple odor which was associated with mostly positive things, such as apples, soap, and candy, but disliked the fish odor, which was associated with mostly negative things, such as dead fish, trash, and vomit). The odor WAVEs (weighted affective valence estimates) performed significantly better than one based on preference for only the namesake object (eg predicting preference for the apple odor based on preference for apples). These results suggest that preferences for familiar odors are based on a summary statistic, coding the valence of previous odor-related experiences. We discuss how this account of odor preferences is consistent with the idea that odor preferences exist to guide organisms to approach beneficial objects and situations and avoid harmful ones.

  7. A “Misfit” Theory of Spontaneous Conscious Odor Perception (MITSCOP): reflections on the role and function of odor memory in everyday life

    Science.gov (United States)

    Köster, Egon P.; Møller, Per; Mojet, Jozina

    2014-01-01

    Our senses have developed as an answer to the world we live in (Gibson, 1966) and so have the forms of memory that accompany them. All senses serve different purposes and do so in different ways. In vision, where orientation and object recognition are important, memory is strongly linked to identification. In olfaction, the guardian of vital functions such as breathing and food ingestion, perhaps the most important (and least noticed and researched) role of odor memory is to help us not to notice the well-known odors or flavors in our everyday surroundings, but to react immediately to the unexpected ones. At the same time it provides us with a feeling of safety when our expectancies are met. All this happens without any smelling intention or conscious knowledge of our expectations. Identification by odor naming is not involved in this and people are notoriously bad at it. Odors are usually best identified via the episodic memory of the situation in which they once occurred. Spontaneous conscious odor perception normally only occurs in situations where attention is demanded, either because the inhaled air or the food smell is particularly good or particularly bad and people search for its source or because people want to actively enjoy the healthiness and pleasantness of their surroundings or food. Odor memory is concerned with novelty detection rather than with recollection of odors. In this paper, these points are illustrated with experimental results and their consequences for doing ecologically valid odor memory research are drawn. Furthermore, suggestions for ecologically valid research on everyday odor memory and some illustrative examples are given. PMID:24575059

  8. Olfactory Imagination and Odor Processing: Three Same-Different Experiments

    NARCIS (Netherlands)

    Koster, E.P.; Stelt, van der O.; Nixdorf, R.R.; Linschoten, M.R.I.; Mojet, J.; Wijk, de R.A.

    2014-01-01

    Do people who claim to have olfactory imagination process odors more efficiently? In three same–different experiments, using all possible combinations of odors and odor names as primes and targets, selected high imagers (n¿=¿12) were faster (±230 ms; P¿

  9. Effect of aging on hedonic appreciation of pleasant and unpleasant odors.

    Directory of Open Access Journals (Sweden)

    Pauline Joussain

    Full Text Available Does hedonic appreciation evolve differently for pleasant odors and unpleasant odors during normal aging? To answer this question we combined psychophysics and electro-encephalographic recordings in young and old adults. A first study showed that pleasant odorants (but not unpleasant ones were rated as less pleasant by old adults. A second study validated this decrease in hedonic appreciation for agreeable odors and further showed that smelling these odorants decreased beta event-related synchronization in aged participants. In conclusion, the study offers new insights into the evolution of odor hedonic perception during normal aging, highlighting for the first time a change in processing pleasant odors.

  10. Odors as triggering and worsening factors for migraine in men

    Directory of Open Access Journals (Sweden)

    A M Lima

    2011-01-01

    Full Text Available OBJECTIVE: To assess the role of odors in triggering or worsening migraine in men. METHOD: Ninety-eight male migraineurs from the general population were assessed individually through questionnaires. Environmental factors relating to their migraine were reported, with special focus on the role of odors. RESULTS: Odors were the second most frequent triggering factor for migraine attacks (48%, behind stressful situations (59%. Likewise, odors were the second most frequent worsening factor (73%, just behind excessive light (74%. Thirty-three individuals (33.4% stated that odors were both triggering and worsening factors for their migraine attacks. Perfume, cigarette smoke and cleaning products were the most frequent migraine-related odors reported by these male migraineurs. CONCLUSION: This was the first study to assess the role of odors in migraine exclusively in men. There was a high degree of odor-related migraine among these men, thus suggesting that patient education could alert such individuals to gender-related factors, since different triggering and worsening factors have been reported by males and females.

  11. Multisensory integration for odor tracking by flying Drosophila: Behavior, circuits and speculation.

    Science.gov (United States)

    Duistermars, Brian J; Frye, Mark A

    2010-01-01

    Many see fruit flies as an annoyance, invading our homes with a nagging persistence and efficiency. Yet from a scientific perspective, these tiny animals are a wonder of multisensory integration, capable of tracking fragmented odor plumes amidst turbulent winds and constantly varying visual conditions. The peripheral olfactory, mechanosensory, and visual systems of the fruit fly, Drosophila melanogaster, have been studied in great detail;1-4 however, the mechanisms by which fly brains integrate information from multiple sensory modalities to facilitate robust odor tracking remain elusive. Our studies on olfactory orientation by flying flies reveal that these animals do not simply follow their "nose"; rather, fruit flies require mechanosensory and visual input to track odors in flight.5,6 Collectively, these results shed light on the neural circuits involved in odor localization by fruit flies in the wild and illuminate the elegant complexity underlying a behavior to which the annoyed and amazed are familiar.

  12. Exposure to predator odor influences the relative use of multiple memory systems: role of basolateral amygdala.

    Science.gov (United States)

    Leong, Kah-Chung; Packard, Mark G

    2014-03-01

    In a dual-solution plus-maze task in which both hippocampus-dependent place learning and dorsolateral striatal-dependent response learning provide an adequate solution, the relative use of multiple memory systems can be influenced by emotional state. Specifically, pre-training peripheral or intra-basolateral (BLA) administration of anxiogenic drugs result in the predominant use of response learning. The present experiments were designed to extend these findings by examining whether exposure to a putatively ethologically valid stressor would also produce a predominant use of response learning. In experiment 1, adult male Long-Evans rats were exposed to either a predator odor (trimethylthiazoline [TMT], a component of fox feces) or distilled water prior to training in a dual-solution water plus maze task. On a probe trial 24h following task acquisition, rats previously exposed to TMT predominantly displayed response learning relative to control animals. In experiment 2, rats trained on a single-solution plus maze task that required the use of response learning displayed enhanced acquisition following pre-training TMT exposure. In experiment 3, rats exposed to TMT or distilled water were trained in the dual-solution task and received post-training intra-BLA injections of the sodium channel blocker bupivacaine (1.0% solution, 0.5 μl) or saline. Relative to control animals, rats exposed to TMT predominantly displayed response learning on the probe trial, and this effect was blocked by neural inactivation of the BLA. The findings indicate that (1) the use of dorsal striatal-dependent habit memory produced by emotional arousal generalizes from anxiogenic drug administration to a putatively ecologically valid stressor (i.e. predator odor), and (2) the BLA mediates the modulatory effect of exposure to predator odor on the relative use of multiple memory systems. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Isoamyl alcohol odor promotes longevity and stress tolerance via DAF-16 in Caenorhabditis elegans.

    Science.gov (United States)

    Kurino, Chiho; Furuhashi, Tsubasa; Sudoh, Kaori; Sakamoto, Kazuichi

    2017-04-01

    The possibility that odor plays a role in lifespan regulation through effects on the nervous system is indicated by research on Caenorhabditis elegans. In fact, ablation of AWA and AWC, which are suggested as olfactory neurons, has been shown to extend lifespan via DAF-16, a homolog of FoxO. However, the effects of odor stimuli on the lifespan still remain unclear. Thus, we here aimed to clarify the effect of attractive and repulsive odors on longevity and stress tolerance in C. elegans and to analyze the pathways thereof. We used isoamyl alcohol as an attractive odor, and acetic acid as a repellent component, as identified by chemotaxis assay. We found that isoamyl alcohol stimulus promoted longevity in a DAF-16-dependent manner. On the other hand, acetic acid stimulus promoted thermotolerance through mechanisms independent of DAF-16. Above all, our results indicate that odor stimuli affect the lifespan and stress tolerance of C. elegans, with attractive and repulsive odors exerting their effects through different mechanisms, and that longevity is induced by both activation and inactivation of olfactory neurons. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Cross-Cultural Color-Odor Associations

    OpenAIRE

    Levitan, Carmel A.; Ren, Jiana; Woods, Andy T.; Boesveldt, Sanne; Chan, Jason S.; McKenzie, Kirsten J.; Dodson, Michael; Levin, Jai A.; Leong, Christine X. R.; van den Bosch, Jasper J. F.

    2014-01-01

    Colors and odors are associated; for instance, people typically match the smell of strawberries to the color pink or red. These associations are forms of crossmodal correspondences. Recently, there has been discussion about the extent to which these correspondences arise for structural reasons (i.e., an inherent mapping between color and odor), statistical reasons (i.e., covariance in experience), and/or semantically-mediated reasons (i.e., stemming from language). The present study probed th...

  15. Cross-cultural color-odor associations

    OpenAIRE

    Levitan, C.A.; Ren, J.; Boesveldt, S.; Chan, J.; McKenzie, K.J.; Levin, J.A.; Leong, C.X.; Bosch, van den, J.F.

    2014-01-01

    Colors and odors are associated; for instance, people typically match the smell of strawberries to the color pink or red. These associations are forms of crossmodal correspondences. Recently, there has been discussion about the extent to which these correspondences arise for structural reasons (i.e., an inherent mapping between color and odor), statistical reasons (i.e., covariance in experience), and/or semantically-mediated reasons (i.e., stemming from language). The present study probed th...

  16. Utilization of Bagasse Fly Ash to Remove the Unpleasant Odor of Stevia Extract and Soy Milk

    Science.gov (United States)

    Ashadi; Masykuri, M.; Haryono

    2017-04-01

    Stevia is a safe natural sweetener that, but has a slightly unpleasant odor. Soy milk is undoubtedly high nutritional value, soy milk slightly unpleasant odor. Bagasse Fly Ash (BFA) is a sugar factory waste which is abundant, not widely used yet, and allowed to accumulate around the sugar factory. BFA can be activated with a solution of NaOH become adsorbent. Utilization of activated BFA to remove the odor of stevia extract and soy milk means the utilization of a waste to reduce other waste. Deodorizing done by batch system. Before being used as adsorbent, BFA characterized using SEM, XRD, FTIR, and AAS. Odor and color analysis conducted by organoleptic. The results shown activation increases the cavity, BFA containing SiO2 and Al2O3, does not contain Pb, Cr, Cd. The results shown that the BFA can reduce odor of stevia from a scale of 4 to 2, the color becomes more clear, unpleasant odor of soy milk is also reduced.

  17. Identification of character impact odorants of different soybean lecithins.

    Science.gov (United States)

    Stephan, A; Steinhart, H

    1999-07-01

    The potent odorants of standardized, enzymatically hydrolyzed, and deoiled soybean lecithins were characterized systematically by combined gas chromatography/mass spectrometry and olfactometry. Sixty-one odorants were identified; 53 of these odor-active compounds have not previously been reported as odorants of soybean lecithin flavor. By aroma extract dilution analysis and modified combined hedonic and response measurement the following odorants showed the highest flavor dilution factors and CHARM values: (E,E)-2, 4-decadienal (deep-fried), (E)-beta-damascenone (apple-like), 2, 3-diethyl-5-methylpyrazine (roasty, earthy), (E)-2-nonenal (cardboard-like), trans-4,5-epoxy-(E)-2-decenal (metallic), 1-nonen-3-one (mushroom-like), 2-ethyl-3,5-dimethylpyrazine (roasty, earthy), and 1-octen-3-one (mushroom-like). Enzymatic hydrolysis intensified especially the roasty sensation of 2, 3-diethyl-5-methylpyrazine, whereas deoiling effected a general significant decrease in olfactory perception on the nitrogen-containing compounds. In addition, sensory profiles of nasal and retronasal lecithin odor were performed.

  18. Aversive learning of odor-heat associations in ants.

    Science.gov (United States)

    Desmedt, Lucie; Baracchi, David; Devaud, Jean-Marc; Giurfa, Martin; d'Ettorre, Patrizia

    2017-12-15

    Ants have recently emerged as useful models for the study of olfactory learning. In this framework, the development of a protocol for the appetitive conditioning of the maxilla-labium extension response (MaLER) provided the possibility of studying Pavlovian odor-food learning in a controlled environment. Here we extend these studies by introducing the first Pavlovian aversive learning protocol for harnessed ants in the laboratory. We worked with carpenter ants Camponotus aethiops and first determined the capacity of different temperatures applied to the body surface to elicit the typical aversive mandible opening response (MOR). We determined that 75°C is the optimal temperature to induce MOR and chose the hind legs as the stimulated body region because of their high sensitivity. We then studied the ability of ants to learn and remember odor-heat associations using 75°C as the unconditioned stimulus. We studied learning and short-term retention after absolute (one odor paired with heat) and differential conditioning (a punished odor versus an unpunished odor). Our results show that ants successfully learn the odor-heat association under a differential-conditioning regime and thus exhibit a conditioned MOR to the punished odor. Yet, their performance under an absolute-conditioning regime is poor. These results demonstrate that ants are capable of aversive learning and confirm previous findings about the different attentional resources solicited by differential and absolute conditioning in general. © 2017. Published by The Company of Biologists Ltd.

  19. Odor identification: perceptual and semantic dimensions.

    Science.gov (United States)

    Cain, W S; de Wijk, R; Lulejian, C; Schiet, F; See, L C

    1998-06-01

    Five studies explored identification of odors as an aspect of semantic memory. All dealt in one way or another with the accessibility of acquired olfactory information. The first study examined stability and showed that, consistent with personal reports, people can fail to identify an odor one day yet succeed another. Failure turned more commonly to success than vice versa, and once success occurred it tended to recur. Confidence ratings implied that subjects generally knew the quality of their answers. Even incorrect names, though, often carried considerable information which sometimes reflected a semantic and sometimes a perceptual source of errors. The second study showed that profiling odors via the American Society of Testing and Materials list of attributes, an exercise in depth of processing, effected no increment in the identifiability/accessibility beyond an unelaborated second attempt at retrieval. The third study showed that subjects had only a weak ability to predict the relative recognizability of odors they had failed to identify. Whereas the strength of the feeling that they would 'know' an answer if offered choices did not associate significantly with performance for odors, it did for trivia questions. The fourth study demonstrated an association between ability to discriminate among one set of odors and to identify another, but this emerged only after subjects had received feedback about identity, which essentially changed the task to one of recognition and effectively stabilized access. The fifth study illustrated that feedback improves performance dramatically only for odors involved with it, but that mere retrieval leads to some improvement. The studies suggest a research agenda that could include supplemental use of confidence judgments both retrospectively and prospectively in the same subjects to indicate the amount of accessible semantic information; use of second and third guesses to examine subjects' simultaneously held hypotheses about

  20. Odorant transfer characteristics of white bread during baking.

    Science.gov (United States)

    Onishi, Masanobu; Inoue, Michiko; Araki, Tetsuya; Iwabuchi, Hisakatsu; Sagara, Yasuyuki

    2011-01-01

    The potent odorants in the crust and crumb of white bread were identified and quantified by gas chromatography-mass spectrometry and gas chromatography/olfactometry. The weight loss ratio of the samples baked at 220 °C was controlled in the range of 0-28%. The odorants were classified into 5 types by the transfer characteristics: i) All amounts of odorant transferred from the crust to external space (type-I). ii) All transferred from the crust to the crumb and external space (type-II). iii) Certain amount remaining in the crust and the rest transferred to the crumb and external space (type-III). iv) All transferred from the crumb to external space (type-IV). v) Certain amount remaining in the crumb and the rest transferred to the crust and external space (type-V). The odorants of type-IV were not apparent after the crust had formed. The results indicate that the crust could be a barrier to prevent the odorants from being transferred to external space.

  1. Odor Signals of Immune Activation and CNS Inflammation

    Science.gov (United States)

    2014-12-01

    inflammation results in detectable alteration of body odor and that traumatic brain injury (TBI) might similarly produce volatile metabolites specific to...Because both LPS and TBI elicit inflammatory processes and LPS-induced inflammation induces body odor changes, we hypothesized that (1) TBI would...induce a distinct change in body odor and (2) this change would resemble the change induced by LPS. Mice receiving surgery and lateral fluid percussion

  2. Wild western lowland gorillas signal selectively using odor.

    Directory of Open Access Journals (Sweden)

    Michelle Klailova

    Full Text Available Mammals communicate socially through visual, auditory and chemical signals. The chemical sense is the oldest sense and is shared by all organisms including bacteria. Despite mounting evidence for social chemo-signaling in humans, the extent to which it modulates behavior is debated and can benefit from comparative models of closely related hominoids. The use of odor cues in wild ape social communication has been only rarely explored. Apart from one study on wild chimpanzee sniffing, our understanding is limited to anecdotes. We present the first study of wild gorilla chemo-communication and the first analysis of olfactory signaling in relation to arousal levels and odor strength in wild apes. If gorilla scent is used as a signaling mechanism instead of only a sign of arousal or stress, odor emission should be context specific and capable of variation as a function of the relationships between the emitter and perceiver(s. Measured through a human pungency scale, we determined the factors that predicted extreme levels of silverback odor for one wild western lowland gorilla (Gorilla gorilla gorilla group silverback. Extreme silverback odor was predicted by the presence and intensity of inter-unit interactions, silverback anger, distress and long-calling auditory rates, and the absence of close proximity between the silverback and mother of the youngest infant. Odor strength also varied according to the focal silverback's strategic responses during high intensity inter-unit interactions. Silverbacks appear to use odor as a modifiable form of communication; where odor acts as a highly flexible, context dependent signaling mechanism to group members and extra-group units. The importance of olfaction to ape social communication may be especially pertinent in Central African forests where limited visibility may necessitate increased reliance on other senses.

  3. Basic emotions evoked by eugenol odor differ according to the dental experience. A neurovegetative analysis.

    Science.gov (United States)

    Robin, O; Alaoui-Ismaïli, O; Dittmar, A; Vernet-Maury, E

    1999-06-01

    Subjective individual experiences seem to indicate that odors may form strong connections with memories, especially those charged with emotional significance. In the dental field, this could be the case with the odorant eugenol, responsible for the typical clinging odor impregnating the dental office. The odor of eugenol could evoke memories of unpleasant dental experiences and, therefore, negative feelings such as anxiety and fear, since eugenates (cements containing eugenol) are used in potentially painful restorative dentistry. This hypothesis was tested by evaluating the emotional impact of the odor of eugenol through autonomic nervous system (ANS) analysis. The simultaneous variations of six ANS parameters (two electrodermal, two thermovascular and two cardiorespiratory), induced by the inhalation of this odorant, were recorded on volunteer subjects. Vanillin (a pleasant odorant) and propionic acid (an unpleasant one) served as controls. After the experiment, subjects were asked to rate the pleasantness versus unpleasantness of each odorant on an 11-point hedonic scale. The patterns of autonomic responses, obtained for each odorant and each subject, were transcribed into one of the six basic emotions defined by Ekman et al. (happiness, surprise, sadness, fear, anger and disgust). Results were compared between two groups of subjects divided according to their dental experience (fearful and non-fearful dental care subjects) and showed significant differences only for eugenol. This odorant was rated as pleasant by non-fearful dental subjects but unpleasant by fearful dental subjects. The evoked autonomic responses were mainly associated with positive basic emotions (happiness and surprise) in non-fearful dental subjects and with negative basic emotions (fear, anger, disgust) in fearful dental subjects. These results suggest that eugenol can be responsible for different emotional states depending on the subjects' dental experience, which seems to confirm the

  4. HPLC analysis of aldehydes in automobile exhaust gas: Comparison of exhaust odor and irritation in different types of gasoline and diesel engines

    International Nuclear Information System (INIS)

    Roy, Murari Mohon

    2008-01-01

    This study investigated high performance liquid chromatography (HPLC) to identify and measure aldehydes from automobile exhaust gas. Four aldehydes: formaldehyde (HCHO), acetaldehyde (CH 3 CHO), acrolein (H 2 C=CHCHO) and propionaldehyde (CH 3 CH 2 CHO) and one ketone, acetone (CH 3 ) 2 CO are separated. The other higher aldehydes in exhaust gas are very small and cannot be separated. A new method of gas sampling, hereafter called bag sampling in HPLC is introduced instead of the trapping gas sampling method. The superiority of the bag sampling method is its transient gas checking capability. In the second part of this study, HPLC results are applied to compare exhaust odor and irritation of exhaust gases in different types of gasoline and diesel engines. Exhaust odor, irritation and aldehydes are found worst in direct injection (DI) diesel engines and best in some good multi-point injection (MPI) gasoline and direct injection gasoline (DIG) engines. Indirect injection (IDI) diesel engines showed odor, irritation and aldehydes in between the levels of MPI gasoline, DIG and DI diesel engines

  5. The effects of cue distinctiveness on odor-based context-dependent memory.

    Science.gov (United States)

    Herz, R S

    1997-05-01

    The distinctiveness of an ambient odor was examined in relation to its success as a cue in context-dependent memory. Distinctiveness was examined in terms of both cue novelty and contextual appropriateness. Two experiments were conducted in which three different ambient odors that varied in familiarity and contextual appropriateness were manipulated at an incidental word learning encoding session and at a free recall retrieval session 48 h later. Experiment 1 revealed that when a novel ambient odor (osmanthus) was the available context cue, word recall was better than in any other condition. Further, among familiar odor cues, recall was better with a contextually inappropriate odor (peppermint) than with a contextually appropriate odor (clean fresh pine). Experiment 2 confirmed that superior word recall with osmanthus and peppermint depended on the odor cue's being available at both encoding and retrieval, and that the relation of an odor to the situational context is a key factor for predicting its effectiveness as a retrieval cue.

  6. Research on odor interaction between aldehyde compounds via a partial differential equation (PDE) model.

    Science.gov (United States)

    Yan, Luchun; Liu, Jiemin; Qu, Chen; Gu, Xingye; Zhao, Xia

    2015-01-28

    In order to explore the odor interaction of binary odor mixtures, a series of odor intensity evaluation tests were performed using both individual components and binary mixtures of aldehydes. Based on the linear relation between the logarithm of odor activity value and odor intensity of individual substances, the relationship between concentrations of individual constituents and their joint odor intensity was investigated by employing a partial differential equation (PDE) model. The obtained results showed that the binary odor interaction was mainly influenced by the mixing ratio of two constituents, but not the concentration level of an odor sample. Besides, an extended PDE model was also proposed on the basis of the above experiments. Through a series of odor intensity matching tests for several different binary odor mixtures, the extended PDE model was proved effective at odor intensity prediction. Furthermore, odorants of the same chemical group and similar odor type exhibited similar characteristics in the binary odor interaction. The overall results suggested that the PDE model is a more interpretable way of demonstrating the odor interactions of binary odor mixtures.

  7. Visualization of odor-induced neuronal activity by immediate early gene expression

    Directory of Open Access Journals (Sweden)

    Bepari Asim K

    2012-11-01

    Full Text Available Abstract Background Sensitive detection of sensory-evoked neuronal activation is a key to mechanistic understanding of brain functions. Since immediate early genes (IEGs are readily induced in the brain by environmental changes, tracing IEG expression provides a convenient tool to identify brain activity. In this study we used in situ hybridization to detect odor-evoked induction of ten IEGs in the mouse olfactory system. We then analyzed IEG induction in the cyclic nucleotide-gated channel subunit A2 (Cnga2-null mice to visualize residual neuronal activity following odorant exposure since CNGA2 is a key component of the olfactory signal transduction pathway in the main olfactory system. Results We observed rapid induction of as many as ten IEGs in the mouse olfactory bulb (OB after olfactory stimulation by a non-biological odorant amyl acetate. A robust increase in expression of several IEGs like c-fos and Egr1 was evident in the glomerular layer, the mitral/tufted cell layer and the granule cell layer. Additionally, the neuronal IEG Npas4 showed steep induction from a very low basal expression level predominantly in the granule cell layer. In Cnga2-null mice, which are usually anosmic and sexually unresponsive, glomerular activation was insignificant in response to either ambient odorants or female stimuli. However, a subtle induction of c-fos took place in the OB of a few Cnga2-mutants which exhibited sexual arousal. Interestingly, very strong glomerular activation was observed in the OB of Cnga2-null male mice after stimulation with either the neutral odor amyl acetate or the predator odor 2, 3, 5-trimethyl-3-thiazoline (TMT. Conclusions This study shows for the first time that in vivo olfactory stimulation can robustly induce the neuronal IEG Npas4 in the mouse OB and confirms the odor-evoked induction of a number of IEGs. As shown in previous studies, our results indicate that a CNGA2-independent signaling pathway(s may activate the

  8. Modeling the generation and dispersion of odors from mushroom composting facilities

    International Nuclear Information System (INIS)

    Heinemann, P.; Wahanik, D.

    1998-01-01

    An odor source generation model and an odor dispersion model were developed to predict the local distribution of odors emanating from mushroom composting facilities. The odor source generation model allowed for simulation of various composting wharf configurations and odor source strengths. This model was linked to a Gaussian plume diffusion model that predicted odor dispersion. Dimethyl disulfide production at a rate of 1760 micrograms/h was simulated by the source generation model and six different atmospheric conditions were analyzed to demonstrate the effect of wind speed, atmospheric stability, and source generation on the dispersion of this odor producing compound. Detectable levels of dimethyl disulfide were predicted to range from less than 100 m from the source during very unstable conditions to almost 5000 m during very stable conditions

  9. The consequence of fetal ethanol exposure and adolescent odor re-exposure on the response to ethanol odor in adolescent and adult rats

    Directory of Open Access Journals (Sweden)

    Molina Juan C

    2009-01-01

    Full Text Available Abstract Background An epidemiologic predictive relationship exists between fetal ethanol exposure and the likelihood for adolescent use. Further, an inverse relationship exists between the age of first experience and the probability of adult abuse. Whether and how the combined effects of prenatal and adolescent ethanol experiences contribute to this progressive pattern remains unknown. Fetal ethanol exposure directly changes the odor attributes of ethanol important for both ethanol odor preference behavior and ethanol flavor perception. These effects persist only to adolescence. Here we tested whether adolescent ethanol odor re-exposure: (Experiment 1 augments the fetal effect on the adolescent behavioral response to ethanol odor; and/or (Experiment 2 perpetuates previously observed adolescent behavioral and neurophysiological responses into adulthood. Methods Pregnant rats received either an ethanol or control liquid diet. Progeny (observers experienced ethanol odor in adolescence via social interaction with a peer (demonstrators that received an intragastric infusion of either 1.5 g/kg ethanol or water. Social interactions were scored for the frequency that observers followed their demonstrator. Whole-body plethysmography evaluated the unconditioned behavioral response of observers to ethanol odor in adolescence (P37 or adulthood (P90. The olfactory epithelium of adults was also examined for its neural response to five odorants, including ethanol. Results Experiment 1: Relative to fetal or adolescent exposure alone, adolescent re-exposure enhanced the behavioral response to ethanol odor in P37 animals. Compared to animals with no ethanol experience, rats receiving a single experience (fetal or adolescent show an enhanced, yet equivalent, ethanol odor response. Fetal ethanol experience also increased olfactory-guided following of an intoxicated peer. Experiment 2: Combined exposure yielded persistence of the behavioral effects only in adult

  10. Odor-induced recall of emotional memories in PTSD-Review and new paradigm for research.

    Science.gov (United States)

    Daniels, Judith K; Vermetten, Eric

    2016-10-01

    It is clinically well known that olfactory intrusions in PTSD can be a disabling phenomena due to the involuntary recall of odor memories. Odorants can trigger involuntary recall of emotional memories as well have the potential to help diminishing emotional arousal as grounding stimuli. Despite major advances in our understanding of the function of olfactory system, the study of the relation of olfaction and emotional memory is still relatively scarce. Odor memory is long thought to be different than other types of memories such as verbal or visual memories, being more strongly engraved and more closely related to strong emotions. Brain areas mediating smell memory including orbitofrontal cortex and other parts of medial prefrontal cortex, hippocampus and amygdala, have been implicated in learning and memory and are part of a neural circuitry that is involved in PTSD. The olfactory cortex itself also plays an important role in emotional processing. Clinical observations support the notion that odor-evoked memories can play a role in the symptomatology of PTSD. This paper reviews a re-emerging body of science linking odor processing to emotional processing in PTSD using the calming and grounding effect of odors as well as the use of odors in augmented exposure therapy. This results in converging evidence that olfaction is an excellent model for studying many questions germane to the field of human emotional memory processing. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. [Remote sensing monitoring and screening for urban black and odorous water body: A review.

    Science.gov (United States)

    Shen, Qian; Zhu, Li; Cao, Hong Ye

    2017-10-01

    Continuous improvement of urban water environment and overall control of black and odorous water body are not merely national strategic needs with the action plan for prevention and treatment of water pollution, but also the hot issues attracting the attention of people. Most previous researches concentrated on the study of cause, evaluation and treatment measures of this phenomenon, and there are few researches on the monitoring using remote sensing, which is often a strain to meet the national needs of operational monitoring. This paper mainly summarized the urgent research problems, mainly including the identification and classification standard, research on the key technologies, and the frame of remote sensing screening systems for the urban black and odorous water body. The main key technologies were concluded too, including the high spatial resolution image preprocessing and extraction technique for black and odorous water body, the extraction of water information in city zones, the classification of the black and odorous water, and the identification and classification technique based on satellite-sky-ground remote sensing. This paper summarized the research progress and put forward research ideas of monitoring and screening urban black and odorous water body via high spatial resolution remote sensing technology, which would be beneficial to having an overall grasp of spatial distribution and improvement progress of black and odorous water body, and provide strong technical support for controlling urban black and odorous water body.

  12. Robust and Rapid Air-Borne Odor Tracking without Casting1,2,3

    Science.gov (United States)

    Bhattacharyya, Urvashi

    2015-01-01

    Abstract Casting behavior (zigzagging across an odor stream) is common in air/liquid-borne odor tracking in open fields; however, terrestrial odor localization often involves path selection in a familiar environment. To study this, we trained rats to run toward an odor source in a multi-choice olfactory arena with near-laminar airflow. We find that rather than casting, rats run directly toward an odor port, and if this is incorrect, they serially sample other sources. This behavior is consistent and accurate in the presence of perturbations, such as novel odors, background odor, unilateral nostril stitching, and turbulence. We developed a model that predicts that this run-and-scan tracking of air-borne odors is faster than casting, provided there are a small number of targets at known locations. Thus, the combination of best-guess target selection with fallback serial sampling provides a rapid and robust strategy for finding odor sources in familiar surroundings. PMID:26665165

  13. Eye-catching odors: olfaction elicits sustained gazing to faces and eyes in 4-month-old infants.

    Science.gov (United States)

    Durand, Karine; Baudouin, Jean-Yves; Lewkowicz, David J; Goubet, Nathalie; Schaal, Benoist

    2013-01-01

    This study investigated whether an odor can affect infants' attention to visually presented objects and whether it can selectively direct visual gaze at visual targets as a function of their meaning. Four-month-old infants (n = 48) were exposed to their mother's body odors while their visual exploration was recorded with an eye-movement tracking system. Two groups of infants, who were assigned to either an odor condition or a control condition, looked at a scene composed of still pictures of faces and cars. As expected, infants looked longer at the faces than at the cars but this spontaneous preference for faces was significantly enhanced in presence of the odor. As expected also, when looking at the face, the infants looked longer at the eyes than at any other facial regions, but, again, they looked at the eyes significantly longer in the presence of the odor. Thus, 4-month-old infants are sensitive to the contextual effects of odors while looking at faces. This suggests that early social attention to faces is mediated by visual as well as non-visual cues.

  14. Age-Related Changes in Children's Hedonic Response to Male Body Odor.

    Science.gov (United States)

    Stevenson, Richard J.; Repacholi, Betty M.

    2003-01-01

    Examined children's and adolescents' ability to identify male sweat and other odors and their rating of odors for liking. Found that only female adolescents could identify and disliked male sweat. When cued about odor identity, both male and female adolescents disliked male sweat more than children. Concluded that dislike for male sweat odor may…

  15. Calmodulin affects sensitization of Drosophila melanogaster odorant receptors

    Directory of Open Access Journals (Sweden)

    Latha eMukunda

    2016-02-01

    Full Text Available Flying insects have developed a remarkably sensitive olfactory system to detect faint and turbulent odor traces. This ability is linked to the olfactory receptors class of odorant receptors (ORs, occurring exclusively in winged insects. ORs form heteromeric complexes of an odorant specific receptor protein (OrX and a highly conserved co-receptor protein (Orco. The ORs form ligand gated ion channels that are tuned by intracellular signaling systems. Repetitive subthreshold odor stimulation of olfactory sensory neurons sensitizes insect ORs. This OR sensitization process requires Orco activity. In the present study we first asked whether OR sensitization can be monitored with heterologously expressed OR proteins. Using electrophysiological and calcium imaging methods we demonstrate that D. melanogaster OR proteins expressed in CHO cells show sensitization upon repeated weak stimulation. This was found for OR channels formed by Orco as well as by Or22a or Or56a and Orco. Moreover, we show that inhibition of calmodulin (CaM action on OR proteins, expressed in CHO cells, abolishes any sensitization. Finally, we investigated the sensitization phenomenon using an ex vivo preparation of olfactory sensory neurons (OSNs expressing Or22a inside the fly’s antenna. Using calcium imaging, we observed sensitization in the dendrites as well as in the soma. Inhibition of calmodulin with W7 disrupted the sensitization within the outer dendritic shaft, whereas the sensitization remained in the other OSN compartments. Taken together, our results suggest that CaM action is involved in sensitizing the OR complex and that this mechanisms accounts for the sensitization in the outer dendrites, whereas further mechanisms contribute to the sensitization observed in the other OSN compartments. The use of heterologously expressed OR proteins appears to be suitable for further investigations on the mechanistic basis of OR sensitization, while investigations on native

  16. Olfaction and Hearing Based Mobile Robot Navigation for Odor/Sound Source Search

    Science.gov (United States)

    Song, Kai; Liu, Qi; Wang, Qi

    2011-01-01

    Bionic technology provides a new elicitation for mobile robot navigation since it explores the way to imitate biological senses. In the present study, the challenging problem was how to fuse different biological senses and guide distributed robots to cooperate with each other for target searching. This paper integrates smell, hearing and touch to design an odor/sound tracking multi-robot system. The olfactory robot tracks the chemical odor plume step by step through information fusion from gas sensors and airflow sensors, while two hearing robots localize the sound source by time delay estimation (TDE) and the geometrical position of microphone array. Furthermore, this paper presents a heading direction based mobile robot navigation algorithm, by which the robot can automatically and stably adjust its velocity and direction according to the deviation between the current heading direction measured by magnetoresistive sensor and the expected heading direction acquired through the odor/sound localization strategies. Simultaneously, one robot can communicate with the other robots via a wireless sensor network (WSN). Experimental results show that the olfactory robot can pinpoint the odor source within the distance of 2 m, while two hearing robots can quickly localize and track the olfactory robot in 2 min. The devised multi-robot system can achieve target search with a considerable success ratio and high stability. PMID:22319401

  17. Olfaction and Hearing Based Mobile Robot Navigation for Odor/Sound Source Search

    Directory of Open Access Journals (Sweden)

    Qi Wang

    2011-02-01

    Full Text Available Bionic technology provides a new elicitation for mobile robot navigation since it explores the way to imitate biological senses. In the present study, the challenging problem was how to fuse different biological senses and guide distributed robots to cooperate with each other for target searching. This paper integrates smell, hearing and touch to design an odor/sound tracking multi-robot system. The olfactory robot tracks the chemical odor plume step by step through information fusion from gas sensors and airflow sensors, while two hearing robots localize the sound source by time delay estimation (TDE and the geometrical position of microphone array. Furthermore, this paper presents a heading direction based mobile robot navigation algorithm, by which the robot can automatically and stably adjust its velocity and direction according to the deviation between the current heading direction measured by magnetoresistive sensor and the expected heading direction acquired through the odor/sound localization strategies. Simultaneously, one robot can communicate with the other robots via a wireless sensor network (WSN. Experimental results show that the olfactory robot can pinpoint the odor source within the distance of 2 m, while two hearing robots can quickly localize and track the olfactory robot in 2 min. The devised multi-robot system can achieve target search with a considerable success ratio and high stability.

  18. Structure-odor relationships of linalool, linalyl acetate and their corresponding oxygenated derivatives

    Science.gov (United States)

    Elsharif, Shaimaa; Banerjee, Ashutosh; Buettner, Andrea

    2015-10-01

    Linalool 1 is an odorant that is commonly perceived as having a pleasant odor, but is also known to elicit physiological effects such as inducing calmness and enhancing sleep. However, no comprehensive studies are at hand to show which structural features are responsible for these prominent effects. Therefore, a total of six oxygenated derivatives were synthesized from both 1 and linalyl acetate 2, and were tested for their odor qualities and relative odor thresholds (OTs) in air. Linalool was found to be the most potent odorant among the investigated compounds, with an average OT of 3.2 ng/L, while the 8-hydroxylinalool derivative was the least odorous compound with an OT of 160 ng/L; 8-carboxylinalool was found to be odorless. The odorant 8-oxolinalyl acetate, which has very similar odor properties to linalool, was the most potent odorant besides linalool, exhibiting an OT of 5.9 ng/L. By comparison, 8-carboxylinalyl acetate had a similar OT (6.1 ng/L) as its corresponding 8-oxo derivative but exhibited divergent odor properties (fatty, greasy, musty). Overall, oxygenation on carbon 8 had a substantial effect on the aroma profiles of structural derivatives of linalool and linalyl acetate.

  19. Photocatalytic and Adsorptive System for Odor Control in Lunar Surface Systems Using Silica-Titania Composites, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed work herein focuses on waste subsystems with emphasis on odor control associated with volatile organic compounds (VOCs). The development of efficient...

  20. Photocatalytic and Adsorptive System for Odor Control in Lunar Surface Systems Using Silica-Titania Composites, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The work proposed herein focuses on waste subsystems with emphasis on odor control associated with volatile organic compounds (VOCs). The development of efficient...

  1. Individually identifiable body odors are produced by the gorilla and discriminated by humans.

    Science.gov (United States)

    Hepper, Peter G; Wells, Deborah L

    2010-05-01

    Many species produce odor cues that enable them to be identified individually, as well as providing other socially relevant information. Study of the role of odor cues in the social behavior of great apes is noticeable by its absence. Olfaction has been viewed as having little role in guiding behavior in these species. This study examined whether Western lowland gorillas produce an individually identifiable odor. Odor samples were obtained by placing cloths in the gorilla's den. A delayed matching to sample task was used with human participants (n = 100) to see if they were able to correctly match a target odor sample to a choice of either: 2 odors (the target sample and another, Experiment 1) and 6 odors (the target sample and 5 others, Experiment 2). Participants were correctly able to identify the target odor when given either 2 or 6 matches. Subjects made fewest errors when matching the odor of the silverback, whereas matching the odors of the young gorillas produced most errors. The results indicate that gorillas do produce individually identifiable body odors and introduce the possibility that odor cues may play a role in gorilla social behavior.

  2. The role of algae and cyanobacteria in the production and release of odorants in water.

    Science.gov (United States)

    Lee, Jechan; Rai, Prabhat Kumar; Jeon, Young Jae; Kim, Ki-Hyun; Kwon, Eilhann E

    2017-08-01

    This review covers literatures pertaining to algal and cyanobacterial odor problems that have been published over the last five decades. Proper evaluation of algal and cyanobacterial odors may help establish removal strategies for hazardous metabolites while enhancing the recyclability of water. A bloom of microalgae is a sign of an anthropogenic disturbance in aquatic systems and can lead to diverse changes in ecosystems along with increased production of odorants. In general, because algal and cyanobacterial odors vary in chemistry and intensity according to blooming pattern, it is necessary to learn more about the related factors and processes (e.g., changes due to differences in taxa). This necessitates systematic and transdisciplinary approaches that require the cooperation of chemists, biologists, engineers, and policy makers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. The major histocompatibility complex and perfumers' descriptions of human body odors

    OpenAIRE

    Wedekind, C.; Escher, S.; Van de Waal, M.; Frei, E.

    2007-01-01

    The MHC (major histocompatibility complex) is a group of genes that play a crucial role in immune recognition and in tolerance of tissue grafting. The MHC has also been found to influence body odors, body odor preferences, and mate choice in mice and humans. Here we test whether verbal descriptions of human body odors can be linked to the MHC. We asked 45 male students to live as odor neutral as possible for two consecutive days and to wear a T-shirt during the nights. The odors of these T-sh...

  4. Association of Odor Thresholds and Responses in Cerebral Blood Flow of the Prefrontal Area during Olfactory Stimulation in Patients with Multiple Chemical Sensitivity.

    Directory of Open Access Journals (Sweden)

    Kenichi Azuma

    Full Text Available Multiple chemical sensitivity (MCS is a disorder characterized by nonspecific and recurrent symptoms from various organ systems associated with exposure to low levels of chemicals. Patients with MCS process odors differently than controls do. Previously, we suggested that this odor processing was associated with increased regional cerebral blood flow (rCBF in the prefrontal area during olfactory stimulation using near-infrared spectroscopic (NIRS imaging. The aim of this study was to investigate the association of odor thresholds and changes in rCBF during olfactory stimulation at odor threshold levels in patients with MCS. We investigated changes in the prefrontal area using NIRS imaging and a T&T olfactometer during olfactory stimulation with two different odorants (sweet and fecal at three concentrations (zero, odor recognition threshold, and normal perceived odor level in 10 patients with MCS and six controls. The T&T olfactometer threshold test and subjective assessment of irritating and hedonic odors were also performed. The results indicated that the scores for both unpleasant and pungent odors were significantly higher for those for sweet odors at the normal perceived level in patients with MCS than in controls. The brain responses at the recognition threshold (fecal odor and normal perceived levels (sweet and fecal odors were stronger in patients with MCS than in controls. However, significant differences in the odor detection and recognition thresholds and odor intensity score between the two groups were not observed. These brain responses may involve cognitive and memory processing systems during past exposure to chemicals. Further research regarding the cognitive features of sensory perception and memory due to past exposure to chemicals and their associations with MCS symptoms is needed.

  5. Olfactory fingerprints for major histocompatibility complex-determined body odors.

    Science.gov (United States)

    Schaefer, M L; Young, D A; Restrepo, D

    2001-04-01

    Recognition of individual body odors is analogous to human face recognition in that it provides information about identity. Individual body odors determined by differences at the major histocompatibility complex (MHC or H-2) have been shown to influence mate choice, pregnancy block, and maternal behavior in mice. Unfortunately, the mechanism and extent of the main olfactory bulb (MOB) and accessory olfactory bulb (AOB) involvement in the discrimination of animals according to H-2-type has remained ambiguous. Here we study the neuronal activation patterns evoked in the MOB in different individuals on exposure to these complex, biologically meaningful sensory stimuli. We demonstrate that body odors from H-2 disparate mice evoke overlapping but distinct maps of neuronal activation in the MOB. The spatial patterns of odor-evoked activity are sufficient to be used like fingerprints to predict H-2 identity using a novel computer algorithm. These results provide functional evidence for discrimination of H-2-determined body odors in the MOB, but do not preclude a role for the AOB. These data further our understanding of the neural strategies used to decode socially relevant odors.

  6. Epac Activation Initiates Associative Odor Preference Memories in the Rat Pup

    Science.gov (United States)

    Grimes, Matthew T.; Powell, Maria; Gutierrez, Sandra Mohammed; Darby-King, Andrea; Harley, Carolyn W.; McLean, John H.

    2015-01-01

    Here we examine the role of the exchange protein directly activated by cAMP (Epac) in ß-adrenergic-dependent associative odor preference learning in rat pups. Bulbar Epac agonist (8-pCPT-2-O-Me-cAMP, or 8-pCPT) infusions, paired with odor, initiated preference learning, which was selective for the paired odor. Interestingly, pairing odor with Epac…

  7. Selectivity of Odorant Receptors in Insects

    Science.gov (United States)

    2012-07-13

    Luetje, C. W., and Robertson, H. M. (2007). A honey bee odorant receptor for the queen substance 9-oxo-2-decenoic acid. Proc. Natl. Acad. Sci. U.S.A...since they might be exposed to a greater number of pharmacolog- ically active compounds than other conventional ligand-gated ion channels and G- protein ...2008). Drosophila odorant receptors are novel seven transmembrane domain proteins that can signal independently of heterotrimeric G proteins

  8. The mere exposure effect depends on an odor's initial pleasantness.

    Science.gov (United States)

    Delplanque, Sylvain; Coppin, Géraldine; Bloesch, Laurène; Cayeux, Isabelle; Sander, David

    2015-01-01

    The mere exposure phenomenon refers to improvement of one's attitude toward an a priori neutral stimulus after its repeated exposure. The extent to which such a phenomenon influences evaluation of a priori emotional stimuli remains under-investigated. Here we investigated this question by presenting participants with different odors varying in a priori pleasantness during different sessions spaced over time. Participants were requested to report each odor's pleasantness, intensity, and familiarity. As expected, participants became more familiar with all stimuli after the repetition procedure. However, while neutral and mildly pleasant odors showed an increase in pleasantness ratings, unpleasant and very pleasant odors remained unaffected. Correlational analyses revealed an inverse U-shape between the magnitude of the mere exposure effect and the initial pleasantness of the odor. Consequently, the initial pleasantness of the stimuli appears to modulate the impact of repeated exposures on an individual's attitude. These data underline the limits of mere exposure effect and are discussed in light of the biological relevance of odors for individual survival.

  9. The Major Histocompatibility Complex and Perfumers' Descriptions of Human Body Odors

    Directory of Open Access Journals (Sweden)

    Claus Wedekind

    2007-04-01

    Full Text Available The MHC (major histocompatibility complex is a group of genes that play a crucial role in immune recognition and in tolerance of tissue grafting. The MHC has also been found to influence body odors, body odor preferences, and mate choice in mice and humans. Here we test whether verbal descriptions of human body odors can be linked to the MHC. We asked 45 male students to live as odor neutral as possible for two consecutive days and to wear a T-shirt during the nights. The odors of these T-shirts were then described by five evaluators: two professional perfumers and three laymen. One of the perfumers was able to describe the T-shirt odors in such a way that some of the allelic specificity of the MHC was significantly revealed (after Bonferroni correction for multiple testing. This shows that, although difficult, some people are able to describe MHC-correlated body odor components.

  10. Study of odor inside cars; Kuruma no nioi ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Sato, S.; Ito, H.; Sakakibara, K.; Kaitani, K.; Hamada, C. [Toyota Central Research and Development Labs., Inc., Aichi (Japan); Matsuo, M. [Toyota Motor Corp., Aichi (Japan)

    1998-05-01

    This paper describes odor in automotive cabin. Odor of new cars is rapidly disappeared during the use. This is greatly due to the adaptation of olfaction. The generation of odor is also decreased. It was found that aliphatic and aromatic hydrocarbons were rapidly disappeared. Decrements of oxygen containing and sulfur compounds were low. For amines, high boiling amines increased after three months. The odor component from crews was derived from the exhalation. Trimethylamine, methyl sulfide as well as iso-prene were detected. They could be derived from tobacco smoke, perfume and hair conditioner. Exhaust gas of diesel vehicle going ahead is one of unpleasant odors from the running atmosphere. A correlation coefficient 0.77 was obtained between the stimulation and aldehyde/ketone. A correlation equation was deduced using stimulation, discomfort degree and odor characteristics as object variables and using logarithms of trace analysis values as explanation variables. There are still a lot of unknown issues concerning combined odors. 9 refs., 9 figs., 1 tab.

  11. Odor recognition memory is not idepentently impaired in Parkinson's disease

    NARCIS (Netherlands)

    Boesveldt, S.; Muinck Keizer, de R.J.O.; Wolters, E.C.H.; Berendse, H.W.

    2009-01-01

    The results of previous studies in small groups of Parkinson's disease (PD) patients are inconclusive with regard to the presence of an odor recognition memory impairment in PD. The aim of the present study was to investigate odor recognition memory in PD in a larger group of patients. Odor

  12. Family scents: developmental changes in the perception of kin body odor?

    Science.gov (United States)

    Ferdenzi, Camille; Schaal, Benoist; Roberts, S Craig

    2010-08-01

    There is increasing evidence that human body odors are involved in adaptive behaviors, such as parental attachment in infants or partner choice in adults. The aim of the present study was to investigate changes in body-odor perception around puberty, a period largely ignored for odor-mediated behavioral changes, despite major changes in social needs and in odor emission and perception. Nine families with two children (8 pre-pubertal, aged 7-10, and 10 pubertal, aged 11-18) evaluated body odors of family members and unfamiliar individuals for pleasantness, intensity, and masculinity, and performed a recognition task. The hypothesized emergence of a parent-child mutual aversion for the odor of opposite-sex family members at puberty was not found, contradicting one of the few studies on the topic (Weisfeld et al., J. Exp. Child Psychol. 85:279-295, 2003). However, some developmental changes were observed, including reduced aversion for odor of the same-sex parent, and increased ability of adults, compared to children, to recognize odor of family members. Sex and personality (depressive and aggressive traits) also significantly influenced odor judgments. Further research with larger samples is needed to investigate the poorly explored issue of how olfactory perception of self and family members develops, and how it could correlate with normal reorganizations in social interactions at adolescence.

  13. Post-eclosion odor experience modifies olfactory receptor neuron coding in Drosophila.

    Science.gov (United States)

    Iyengar, Atulya; Chakraborty, Tuhin Subhra; Goswami, Sarit Pati; Wu, Chun-Fang; Siddiqi, Obaid

    2010-05-25

    Olfactory responses of Drosophila undergo pronounced changes after eclosion. The flies develop attraction to odors to which they are exposed and aversion to other odors. Behavioral adaptation is correlated with changes in the firing pattern of olfactory receptor neurons (ORNs). In this article, we present an information-theoretic analysis of the firing pattern of ORNs. Flies reared in a synthetic odorless medium were transferred after eclosion to three different media: (i) a synthetic medium relatively devoid of odor cues, (ii) synthetic medium infused with a single odorant, and (iii) complex cornmeal medium rich in odors. Recordings were made from an identified sensillum (type II), and the Jensen-Shannon divergence (D(JS)) was used to assess quantitatively the differences between ensemble spike responses to different odors. Analysis shows that prolonged exposure to ethyl acetate and several related esters increases sensitivity to these esters but does not improve the ability of the fly to distinguish between them. Flies exposed to cornmeal display varied sensitivity to these odorants and at the same time develop greater capacity to distinguish between odors. Deprivation of odor experience on an odorless synthetic medium leads to a loss of both sensitivity and acuity. Rich olfactory experience thus helps to shape the ORNs response and enhances its discriminative power. The experiments presented here demonstrate an experience-dependent adaptation at the level of the receptor neuron.

  14. Structure-odor relationships of linalool, linalyl acetate and their corresponding oxygenated derivatives

    Directory of Open Access Journals (Sweden)

    Shaimaa eElsharif

    2015-10-01

    Full Text Available Linalool 1 is an odorant that is commonly perceived as having a pleasant odor, but is also known to elicit physiological effects such as inducing calmness and enhancing sleep. However, no comprehensive studies are at hand to show which structural features are responsible for these prominent effects. Therefore, a total of six oxygenated derivatives were synthesized from both 1 and linalyl acetate 2, and were tested for their odor qualities and relative odor thresholds (OTs in air. Linalool was found to be the most potent odorant among the investigated compounds, with an average OT of 3.2 ng/L, while the 8-hydroxylinalool derivative was the least odorous compound with an OT of 160 ng/L; 8-carboxylinalool was found to be odorless. The odorant 8-oxolinalyl acetate, which has very similar odor properties to linalool, was the most potent odorant besides linalool, exhibiting an OT of 5.9 ng/L. By comparison, 8-carboxylinalyl acetate had a similar OT (6.1 ng/L as its corresponding 8-oxo derivative but exhibited divergent odor properties (fatty, greasy, musty. Overall, oxygenation on carbon 8 had a substantial effect on the aroma profiles of structural derivatives of linalool and linalyl acetate.

  15. Intranasal localizability of odorants: influence of stimulus volume.

    Science.gov (United States)

    Frasnelli, J; Hummel, T; Berg, J; Huang, G; Doty, R L

    2011-05-01

    When an odorant is presented to one side of the nose and air to the other, the ability to localize which side received the odorant depends upon trigeminal nerve stimulation. It has been shown that performance on this lateralization task increases as stimulus concentration increases. In this study, we determined the influences of stimulus volume and sex on the ability to localize each of 8 odorants presented at neat concentrations: anethole, geraniol, limonene, linalool, menthol, methyl salicylate, phenyl ethanol, and vanillin. At a low stimulus volume (11 mL), only menthol was localized at an above-chance level. At a high stimulus volume (21 mL), above-chance localization occurred for all odorants except vanillin. Women were significantly better than men in localizing menthol. Stimuli rated as most intense were those that were most readily localized. The detection performance measures, as well as rated intensity values, significantly correlated with earlier findings of the trigeminal detectability of odorants presented to anosmic and normosmic subjects. This study suggests that differences in stimulus volume may explain some discrepant findings within the trigeminal chemosensory literature and supports the concept that vanillin may be a "relatively pure" olfactory stimulus.

  16. Primary odorants of naturally soiled laundry

    DEFF Research Database (Denmark)

    Jepsen, Signe Munk; Münch, Petra; Stahnke, Marie Louise Heller

    2000-01-01

    Odorants still attached to laundry soiled with human axillary sweat and sebum, after a mild washing procedure, were extracted and analysed by aroma extract dilution analysis. Esters (ethyl-2-methylpropanoate and ethylbutanoate), ketones (1-hexen-3-one and 1-octen-3-one) and, in particular......, aldehydes ((Z)-4-heptenal, octanal, (E)-2-octenal, methional, (Z)-2-nonenal, (E,Z)-2,6-nonadienal, (E,Z)-2,4-nonadienal, (E,E)-2,4-decadienal and 4-methoxybenzaldehyde) were identified as primary odorants. Organic acids, which are dominating, characteristic odorants in human axillary sweat, were...... ranking analysis prior to the analytical odour analysis. Swatches selected for the subsequent odour analysis possessed greater odour intensity, when washed in the presence of lipase than the corresponding swatches washed in the absence of lipase. The aroma extract dilution analysis revealed that generally...

  17. Emotional Body Odors as Context: Effects on Cardiac and Subjective Responses.

    Science.gov (United States)

    Ferreira, Jacqueline; Parma, Valentina; Alho, Laura; Silva, Carlos F; Soares, Sandra C

    2018-05-23

    Many studies have indicated that the chemical cues from body odors (BOs) of donors experiencing negative emotions can influence the psychophysiological and behavioral response of the observers. However, these olfactory cues have been used mainly as contextual information for processing visual stimuli. Here, for the first time, we evaluate how emotional BO affects the emotional tone of a subsequent BO message. Axillary sweat samples were taken from 20 donors in 3 separate sessions while they watched fear, disgust, or neutral videos. In a double-blind experiment, we assessed the cardiac and subjective responses from 69 participants who were either exposed to negative emotional or neutral BOs. Our results showed a reduced cardiac parasympathetic activity (HF%)-indicating increased stress-when participants smelled the emotional BOs before the neutral BOs, compared to when they smelled neutral followed by emotional BOs. The intensity of the neutral odor also increased following the exposure to both negative BOs. These findings indicate that BOs contain an emotion-dependent chemical cue that affects the perceiver both at the physiological and subjective levels.

  18. Odor from anaerobic digestion of swine slurry: influence of pH, temperature and organic loading

    Directory of Open Access Journals (Sweden)

    Gerardo Ortiz

    2014-12-01

    Full Text Available Farm slurry management from storage and/or treatment is the main source of odors from swine production, which are determined by factors such as operational variations (organic loading, cleaning of facilities and animal diet (pH or environmental conditions (temperature. The aim of this study was to evaluate the influence of pH, temperature and organic loading on odor generation during anaerobic digestion of swine slurry. The methodology employed batch experimental units under controlled pH (6.0, 6.5, 7.0 and 8.0 and temperature (20, 35 and 55 °C conditions. Additionally, an Upflow Anaerobic Sludge Blanket (UASB system was operated under two Organic Loading Rate (OLR conditions as Chemical Oxygen Demand (COD (Phase I: 0.4 g L-1 d-1 of COD, Phase II: 1.1 g L-1 d-1 of COD. Odor (batch and UASB reactor was evaluated by detection and recognition threshold as Dilution Threshold (D-T. Acidic conditions (pH 6.0 and thermophilic temperatures (55 °C increased odors (1,358 D-T and acidified the system (Intermediate/Total Alkalinity ratio (IT/TA: 0.85 in batch experiments. Increasing OLR on UASB reactor reduced odors from 6.3 to 9.6 D-T d-1 due to an increase in the production of biogas (0.4 to 0.6 g g-1 COD removed of biogas.

  19. α7-Nicotinic acetylcholine receptor: role in early odor learning preference in mice.

    Directory of Open Access Journals (Sweden)

    Jennifer L Hellier

    Full Text Available Recently, we have shown that mice with decreased expression of α7-nicotinic acetylcholine receptors (α7 in the olfactory bulb were associated with a deficit in odor discrimination compared to wild-type mice. However, it is unknown if mice with decreased α7-receptor expression also show a deficit in early odor learning preference (ELP, an enhanced behavioral response to odors with attractive value observed in rats. In this study, we modified ELP methods performed in rats and implemented similar conditions in mice. From post-natal days 5-18, wild-type mice were stroked simultaneously with an odor presentation (conditioned odor for 90 s daily. Control mice were only stroked, exposed to odor, or neither. On the day of testing (P21, mice that were stroked in concert with a conditioned odor significantly investigated the conditioned odor compared to a novel odor, as observed similarly in rats. However, mice with a decrease in α7-receptor expression that were stroked during a conditioned odor did not show a behavioral response to that odorant. These results suggest that decreased α7-receptor expression has a role in associative learning, olfactory preference, and/or sensory processing deficits.

  20. Identification of pleasant, neutral, and unpleasant odors in schizophrenia

    OpenAIRE

    Kamath, Vidyulata; Turetsky, Bruce I.; Moberg, Paul J.

    2011-01-01

    Recent work on odor hedonics in schizophrenia has indicated that patients display abnormalities in hedonic judgments of odors in comparison to healthy comparison participants. In the current study, identification accuracy for pleasant, neutral, and unpleasant odors in individuals with schizophrenia and healthy controls was examined. Thirty-three schizophrenia patients (63% male) and thirty-one healthy volunteers (65% male) were recruited. The groups were well matched on age, sex, and smoking ...

  1. History dependence in insect flight decisions during odor tracking.

    Science.gov (United States)

    Pang, Rich; van Breugel, Floris; Dickinson, Michael; Riffell, Jeffrey A; Fairhall, Adrienne

    2018-02-01

    Natural decision-making often involves extended decision sequences in response to variable stimuli with complex structure. As an example, many animals follow odor plumes to locate food sources or mates, but turbulence breaks up the advected odor signal into intermittent filaments and puffs. This scenario provides an opportunity to ask how animals use sparse, instantaneous, and stochastic signal encounters to generate goal-oriented behavioral sequences. Here we examined the trajectories of flying fruit flies (Drosophila melanogaster) and mosquitoes (Aedes aegypti) navigating in controlled plumes of attractive odorants. While it is known that mean odor-triggered flight responses are dominated by upwind turns, individual responses are highly variable. We asked whether deviations from mean responses depended on specific features of odor encounters, and found that odor-triggered turns were slightly but significantly modulated by two features of odor encounters. First, encounters with higher concentrations triggered stronger upwind turns. Second, encounters occurring later in a sequence triggered weaker upwind turns. To contextualize the latter history dependence theoretically, we examined trajectories simulated from three normative tracking strategies. We found that neither a purely reactive strategy nor a strategy in which the tracker learned the plume centerline over time captured the observed history dependence. In contrast, "infotaxis", in which flight decisions maximized expected information gain about source location, exhibited a history dependence aligned in sign with the data, though much larger in magnitude. These findings suggest that while true plume tracking is dominated by a reactive odor response it might also involve a history-dependent modulation of responses consistent with the accumulation of information about a source over multi-encounter timescales. This suggests that short-term memory processes modulating decision sequences may play a role in

  2. Stressors impair odor recognition memory via an olfactory bulb-dependent noradrenergic mechanism

    Directory of Open Access Journals (Sweden)

    Laura C Manella

    2013-12-01

    Full Text Available Non-associative habituation and odor recognition tasks have been widely used to probe questions social recognition, odor memory duration, and odor memory specificity. Among others, these paradigms have provided valuable insight into how neuromodulation, and specifically norepinephrine/noradrenaline (NE influences odor memory. In general, NE levels are modulated by arousal, stress, and behavioral state, and there is sparse evidence of a direct relationship between NE and odor memory in adult rodents. The present study uses simple mild psychological stressors (bright light and sound, to modulate NE levels physiologically in order to probe its effect on olfactory memory. In rats with bilateral bulbar cannulations, we show that these stressors modulate olfactory memory and that this effect is at least partially mediated by olfactory bulb. Specifically, we show that the presence of stressors during the acquisition of odor memory suppresses memory for an odor when tested 30 minutes after the acquisition. This suppression is blocked by infusing NE antagonists into the olfactory bulb prior to odor acquisition. Additionally, we find that infusion of bulbar NE is sufficient to suppress odor memory in a manner mimicking that of our stressors. These effects are unlikely to be solely mediated by locomotor/exploratory changes produced by stressors, although these stressors influence certain behaviors not directly related to odor investigation. This study provides important information about how behaviorally relevant changes in NE can influence top-down sensory processing and odor memory.

  3. Basic emotions induced by odorants: a new approach based on autonomic pattern results.

    Science.gov (United States)

    Vernet-Maury, E; Alaoui-Ismaïli, O; Dittmar, A; Delhomme, G; Chanel, J

    1999-02-15

    The aim of this study was to link the effects of odorants with the emotional process, through autonomic nervous system (ANS) responses. Taking Ekman's data and our previous results into account, we tried to verify a possible evocation by odorants of some basic emotions, i.e. anger, fear, sadness, surprise, disgust and happiness. The question investigated was: would it be possible to associate any of these emotions with a pattern of autonomic responses? A total of 15 subjects inhaled five odorants: lavender, ethyl aceto acetate, camphor, acetic acid and butyric acid acting as olfactory stimuli. After inhaling the odorant, subjects were requested to fill out an 11-point hedonic scale to rate its 'pleasantness' vs. 'unpleasantness'. ANS parameters monitored were skin potential and resistance, skin blood flow and temperature, instantaneous respiratory frequency and instantaneous heart rate. Simultaneous recording of these six autonomic parameters permitted the analysis of phasic responses through specific ANS patterns. An analysis of variance made it possible to differentiate among the five odorants. Two-by-two odorant comparisons for autonomic responses using Tukey's HSD multiple comparison test only permitted differentiation between 'pleasant' and 'unpleasant' odors. Camphor was differentiated from both types. For instance, long duration responses were associated with 'unpleasant' odors whereas camphor elicited intermediate responses. Taking into account each subject's preferential channel, it was possible to associate each ANS pattern with a basic emotion by means of a decision tree. The computation of subjects' responses made it possible to associate an odorant with a basic emotion, over the whole group: lavender elicited mostly 'happiness', as did, to a lesser degree ethyl aceto acetate; camphor induced either 'happiness', 'surprise' or 'sadness' according to subjects' past histories; butyric and acetic acids mainly induced negative emotions: 'anger' and 'disgust

  4. Real-time odor discrimination using a bioelectronic sensor array based on the insect electroantennogram

    International Nuclear Information System (INIS)

    Myrick, A J; Hetling, J R; Park, K-C; Baker, T C

    2008-01-01

    Current trends in artificial nose research are strongly influenced by knowledge of biological olfactory systems. Insects have evolved over millions of years to detect and maneuver toward a food source or mate, or away from predators. The insect olfactory system is able to identify volatiles on a time scale that matches their ability to maneuver. Here, biological olfactory sense organs, insect antennae, have been exploited in a hybrid-device biosensor, demonstrating the ability to identify individual strands of odor in a plume passing over the sensor on a sub-second time scale. A portable system was designed to utilize the electrophysiological responses recorded from a sensor array composed of male or female antennae from four or eight different species of insects (a multi-channel electroantennogram, EAG). A computational analysis strategy that allows discrimination between odors in real time is described in detail. Following a training period, both semi-parametric and k-nearest neighbor (k-NN) classifiers with the ability to discard ambiguous responses are applied toward the classification of up to eight odors. EAG responses to individual strands in an odor plume are classified or discarded as ambiguous with a delay (sensor response to classification report) on the order of 1 s. The dependence of classification error rate on several parameters is described. Finally, the performance of the approach is compared to that of a minimal conditional risk classifier

  5. Reward for food odors: an fMRI study of liking and wanting as a function of metabolic state and BMI.

    Science.gov (United States)

    Jiang, Tao; Soussignan, Robert; Schaal, Benoist; Royet, Jean-Pierre

    2015-04-01

    Brain reward systems mediate liking and wanting for food reward. Here, we explore the differential involvement of the following structures for these two components: the ventral and dorsal striatopallidal area, orbitofrontal cortex (OFC), anterior insula and anterior cingulate. Twelve healthy female participants were asked to rate pleasantness (liking of food and non-food odors) and the desire to eat (wanting of odor-evoked food) during event-related functional magnetic resonance imaging (fMRI). The subjective ratings and fMRI were performed in hunger and satiety states. Activations of regions of interest were compared as a function of task (liking vs wanting), odor category (food vs non-food) and metabolic state (hunger vs satiety). We found that the nucleus accumbens and ventral pallidum were differentially involved in liking or wanting during the hunger state, which suggests a reciprocal inhibitory influence between these structures. Neural activation of OFC subregions was correlated with either liking or wanting ratings, suggesting an OFC role in reward processing magnitude. Finally, during the hunger state, participants with a high body mass index exhibited less activation in neural structures underlying food reward processing. Our results suggest that food liking and wanting are two separable psychological constructs and may be functionally segregated within the cortico-striatopallidal circuit. © The Author (2014). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  6. Eye-catching odors: olfaction elicits sustained gazing to faces and eyes in 4-month-old infants.

    Directory of Open Access Journals (Sweden)

    Karine Durand

    Full Text Available This study investigated whether an odor can affect infants' attention to visually presented objects and whether it can selectively direct visual gaze at visual targets as a function of their meaning. Four-month-old infants (n = 48 were exposed to their mother's body odors while their visual exploration was recorded with an eye-movement tracking system. Two groups of infants, who were assigned to either an odor condition or a control condition, looked at a scene composed of still pictures of faces and cars. As expected, infants looked longer at the faces than at the cars but this spontaneous preference for faces was significantly enhanced in presence of the odor. As expected also, when looking at the face, the infants looked longer at the eyes than at any other facial regions, but, again, they looked at the eyes significantly longer in the presence of the odor. Thus, 4-month-old infants are sensitive to the contextual effects of odors while looking at faces. This suggests that early social attention to faces is mediated by visual as well as non-visual cues.

  7. Food odors trigger an endocrine response that affects food ingestion and metabolism.

    Science.gov (United States)

    Lushchak, Oleh V; Carlsson, Mikael A; Nässel, Dick R

    2015-08-01

    Food odors stimulate appetite and innate food-seeking behavior in hungry animals. The smell of food also induces salivation and release of gastric acid and insulin. Conversely, sustained odor exposure may induce satiation. We demonstrate novel effects of food odors on food ingestion, metabolism and endocrine signaling in Drosophila melanogaster. Acute exposure to attractive vinegar odor triggers a rapid and transient increase in circulating glucose, and a rapid upregulation of genes encoding the glucagon-like hormone adipokinetic hormone (AKH), four insulin-like peptides (DILPs) and some target genes in peripheral tissues. Sustained exposure to food odors, however, decreases food intake. Hunger-induced strengthening of synaptic signaling from olfactory sensory neurons (OSNs) to brain neurons increases food-seeking behavior, and conversely fed flies display reduced food odor sensitivity and feeding. We show that increasing the strength of OSN signaling chronically by genetic manipulation of local peptide neuromodulation reduces feeding, elevates carbohydrates and diminishes lipids. Furthermore, constitutively strengthened odor sensitivity altered gene transcripts for AKH, DILPs and some of their targets. Thus, we show that food odor can induce a transient anticipatory endocrine response, and that boosted sensitivity to this odor affects food intake, as well as metabolism and hormonal signaling.

  8. Adult neurogenesis in the olfactory system shapes odor memory and perception.

    Science.gov (United States)

    Gheusi, Gilles; Lledo, Pierre-Marie

    2014-01-01

    The olfactory system is a dynamic place. In mammals, not only are sensory neurons located in the sensory organ renewed through adult life, but also its first central relay is reconstructed by continuous neuronal recruitment. Despite these numerous morphological and physiological changes, olfaction is a unique sensory modality endowed with a privileged link to memory. This raises a clear conundrum; how does the olfactory system balance its neuronal turnover with its participation in long-term memory? This review concentrates on the functional aspects of adult neurogenesis, addressing how the integration of late-born neurons participates in olfactory perception and memory. After outlining the properties of adult neurogenesis in the olfactory system, and after describing their regulation by internal and environmental factors, we ask how the process of odorant perception can be influenced by constant neuronal turnover. We then explore the possible functional roles that newborn neurons might have for olfactory memory. Throughout this review, and as we concentrate almost exclusively on mammalian models, we stress the idea that adult neurogenesis is yet another form of plasticity used by the brain to copes with a constantly changing olfactory world. © 2014 Elsevier B.V. All rights reserved.

  9. Sensory-specific appetite is affected by actively smelled food odors and remains stable over time in normal-wight women

    NARCIS (Netherlands)

    Ramaekers, M.G.; Boesveldt, S.; Lakemond, C.M.M.; Boekel, van M.A.J.S.; Luning, P.A.

    2014-01-01

    Understanding overconsumption starts with knowledge of how separate factors influence our eating behavior. Food cues such as food odors are known for their effect on general appetite and sensory-specific appetite (SSA). Active sniffing rather than passive exposure may induce satiation over time. The

  10. Insights into the Key Compounds of Durian (Durio zibethinus L. 'Monthong') Pulp Odor by Odorant Quantitation and Aroma Simulation Experiments.

    Science.gov (United States)

    Li, Jia-Xiao; Schieberle, Peter; Steinhaus, Martin

    2017-01-25

    Sixteen compounds, previously identified as potent odorants by application of an aroma extract dilution analysis and the gas chromatography-olfactometry analysis of static headspace samples, were quantitated in the pulp of durians, variety Monthong, and odor activity values (OAVs) were calculated by dividing the concentrations obtained by the odor thresholds of the compounds in water. In combination with data recently reported for hydrogen sulfide and short-chain alkanethiols, OAVs > 1 were obtained for 19 compounds, among which ethyl (2S)-2-methylbutanoate (fruity; OAV 1700000), ethanethiol (rotten onion; OAV 480000), and 1-(ethylsulfanyl)ethane-1-thiol (roasted onion; OAV 250000) were the most potent, followed by methanethiol (rotten, cabbage; OAV 45000), ethane-1,1-dithiol (sulfury, durian; OAV 23000), and ethyl 2-methylpropanoate (fruity; OAV 22000). Aroma simulation and omission experiments revealed that the overall odor of durian pulp could be mimicked by only two compounds, namely, ethyl (2S)-2-methylbutanoate and 1-(ethylsulfanyl)ethane-1-thiol, when combined in their natural concentrations.

  11. A Specialized Odor Memory Buffer in Primary Olfactory Cortex

    OpenAIRE

    Zelano, Christina; Montag, Jessica; Khan, Rehan; Sobel, Noam

    2009-01-01

    Background The neural substrates of olfactory working memory are unknown. We addressed the questions of whether olfactory working memory involves a verbal representation of the odor, or a sensory image of the odor, or both, and the location of the neural substrates of these processes. Methodology/Principal Findings We used functional magnetic resonance imaging to measure activity in the brains of subjects who were remembering either nameable or unnameable odorants. We found a double dissociat...

  12. Learning modulation of odor representations: new findings from Arc-indexed networks

    Directory of Open Access Journals (Sweden)

    Qi eYuan

    2014-12-01

    Full Text Available We first review our understanding of odor representations in rodent olfactory bulb and anterior piriform cortex. We then consider learning-induced representation changes. Finally we describe the perspective on network representations gained from examining Arc-indexed odor networks of awake rats. Arc-indexed networks are sparse and distributed, consistent with current views. However Arc provides representations of repeated odors. Arc-indexed repeated odor representations are quite variable. Sparse representations are assumed to be compact and reliable memory codes. Arc suggests this is not necessarily the case. The variability seen is consistent with electrophysiology in awake animals and may reflect top down-cortical modulation of context. Arc-indexing shows that distinct odors share larger than predicted neuron pools. These may be low-threshold neuronal subsets.Learning’s effect on Arc-indexed representations is to increase the stable or overlapping component of rewarded odor representations. This component can decrease for similar odors when their discrimination is rewarded. The learning effects seen are supported by electrophysiology, but mechanisms remain to be elucidated.

  13. Proust nose best: odors are better cues of autobiographical memory.

    Science.gov (United States)

    Chu, Simon; Downes, John J

    2002-06-01

    The Proust phenomenon is an enduring piece of folk wisdom that asserts that odors are particularly powerful autobiographical memory cues. We provide a more formal exposition of this phenomenon and test it in two experiments, using a novel double-cuing methodology designed to negate less interesting explanations. In both studies, recall of an autobiographical event was initially cued by a verbal label (an odor name) for a fixed period, following which a second, extended recall attempt was cued by the same verbal label, the relevant odor, an irrelevant odor, or a visual cue. The focus of Experiment 1 was participants' ratings of the emotional quality of their autobiographical memories. In Experiment 2, content analysis was employed to determine the quantity of information in participants' recollections. Results revealed that odor-cued autobiographical memories were reliably different in terms of qualitative ratings and reliably superior in the amount of detail yielded. Moreover, visual cues and incongruent olfactory cues appeared to have a detrimental effect on the amount of detail recalled. These results support the proposal that odors are especially effective as reminders of past experience.

  14. Analysis of Five Earthy-Musty Odorants in Environmental Water by HS-SPME/GC-MS

    Directory of Open Access Journals (Sweden)

    Zhen Ding

    2014-01-01

    Full Text Available The pressing issue of earthy and musty odor compounds in natural waters, which can affect the organoleptic properties of drinking water, makes it a public health concern. A simple and sensitive method for simultaneous analysis of five odorants in environmental water was developed by headspace solid-phase microextraction (HS-SPME coupled to chromatography-mass spectrometry (GC-MS, including geosmin (GSM and 2-methylisoborneol (2-MIB, as well as dimethyl trisulfide (DMTS, β-cyclocitral, and β-ionone. Based on the simple modification of original magnetic stirrer purchased from CORNING (USA, the five target compounds can be separated within 23 min, and the calibration curves show good linearity with a correlation coefficient above 0.999 (levels = 5. The limits of detection (LOD are all below 1.3 ng L−1, and the relative standard deviation (%RSD is between 4.4% and 9.9% (n = 7 and recoveries of the analytes from water samples are between 86.2% and 112.3%. In addition, the storage time experiment indicated that the concentrations did not change significantly for GSM and 2-MIB if they were stored in canonical environment. In conclusion, the method in this study could be applied for monitoring these five odorants in natural waters.

  15. Pollution odorante par les moteurs Diesel. Mesure des odeurs d'échappement Odorous Pollution by Diesel Engines. Measuring Exhaust Odors

    Directory of Open Access Journals (Sweden)

    Degobert P.

    2006-11-01

    Full Text Available Les études de mesure d'odeur Diesel ont commencé en 1956 aux États-Unis, en particulier pour réduire le niveau odorant des autobus. Cet article expose d'abord les mécanismes de formation des odorants puis les études américaines, qui ont abouti en 1973 à l'odorimètre Arthur D. Little, basé sur l'analyse par chromatographie liquide de l'échappement, et ses corrélations avec les données sensorielles recueillies dans des conditions particulières. Les économies d'énergie dans les villes européennes entraînent un accroissement du nombre de véhicules Diesel, ce qui peut amener un niveau odorant incompatible avec le bien-être. C'est pourquoi l'Institut Français du Pétrole (IFP étudie actuellement les odeurs Diesel, pour mettre au point des méthodes de mesure fiables, partant de la chromatographie liquide type Arthur D. Little (ADL et de l'évaluation sensorielle. Les résultats actuels montrent qu'à moins de progrès importants en analyse chimique, l'évaluation sensorielle reste la méthode la plus fiable. Les perspectives futures basées sur l'olfactomètre différentiel Mac Leod sont présentées. Research was beg un in the United States in 1956 on the medsurementof diesel engine odors, and especially on reducing the odor from diesel city buses. This article begins by describing the mechanisms of odor formation and then goes on ta, review US research which resulted in the Arthur D. Little odormeter in 1973, based on a liquid chromatography analysis of exhaust and its corrélations with sensory data gathered under specific conditions. Energy conservation in European cities is tending ta, increase the number of diesel vehicles and possibly ta, create an odor level that is incompatible with humal well-being. This is why Institut Français du Pétrole (IFP is now investigating diesel eng ine odors for the purpose of developing reliable measuring methods based on liquid chromatography of the Arthur D. Little (ADl type and on

  16. Dispersion of odorants in natural gas distribution networks

    Science.gov (United States)

    Gross, R.; Fontana, E.; Silva, A.; Quadri, M. B.; Souza, S. M. A. G. U.

    2018-03-01

    A numerical modeling analysis of a pulse train diffusion, representing an odorant injection in a natural gas pipeline, was carried out and compared with experimental data from a real pipeline. The main purpose of this study is to evaluate how the odorant dispersion occurs along the pipe. Due to technical limitations, the odorant is injected in the line as a pulse and it is important to find out the point in the pipeline where the oscillating concentration of odorant fits into a range of values that meet both the legislation and the interests of customers who may have the quality of their products affected by this oscillation. Since the natural gas pipelines do not have strong streamline curvatures and the flow is always turbulent, it is relatively easy to determine the velocity and concentration fields using the Computational Fluid Dynamics techniques. In this study the RANS (Reynolds Average Navier-Stokes) equations with the k - ɛ turbulence model was used to build the mathematical model. Comparisons of the experimental data and numerical results show a strong agreement for the studied cases. Based on the results, it was possible to know the minimum and maximum values of odorant concentration along the pipelines.

  17. Odor and odorous compound emissions from manure of swine fed standard and dried distillers grains with soluble (DDGS) supplemented diets

    Science.gov (United States)

    This study was conducted to determine the impact diets containing dried distillers grains with soluble (DDGS) have on emissions of odor and odorous compounds from swine manure storage. Twenty-four pigs were fed either a corn-soybean meal (CSBM) diet or a CSBM diet containing 35% DDGS. Pigs were fed ...

  18. Odor impact of volatiles emitted from marijuana, cocaine, heroin and their surrogate scents

    Directory of Open Access Journals (Sweden)

    Somchai Rice

    2015-12-01

    Full Text Available Volatile compounds emitted into headspace from illicit street drugs have been identified, but until now odor impact of these compounds have not been reported. Data in support of identification of these compounds and their odor impact to human nose are presented. In addition, data is reported on odor detection thresholds for canines highlighting differences with human ODTs and needs to address gaps in knowledge. New data presented here include: (1 compound identification, (2 gas chromatography (GC column retention times, (3 mass spectral data, (4 odor descriptors from 2 databases, (5 human odor detection thresholds from 2 databases, (6 calculated odor activity values, and (7 subsequent ranking of compounds by concentration and ranking of compounds by odor impact (reported as calculated odor activity values. For further interpretation and discussion, see Rice and Koziel [1] and Rice [2].

  19. Proposed Objective Odor Control Test Methodology for Waste Containment

    Science.gov (United States)

    Vos, Gordon

    2010-01-01

    The Orion Cockpit Working Group has requested that an odor control testing methodology be proposed to evaluate the odor containment effectiveness of waste disposal bags to be flown on the Orion Crew Exploration Vehicle. As a standardized "odor containment" test does not appear to be a matter of record for the project, a new test method is being proposed. This method is based on existing test methods used in industrial hygiene for the evaluation of respirator fit in occupational settings, and takes into consideration peer reviewed documentation of human odor thresholds for standardized contaminates, industry stardnard atmostpheric testing methodologies, and established criteria for laboratory analysis. The proposed methodology is quantitative, though it can readily be complimented with a qualitative subjective assessment. Isoamyl acetate (IAA - also known at isopentyl acetate) is commonly used in respirator fit testing, and there are documented methodologies for both measuring its quantitative airborne concentrations. IAA is a clear, colorless liquid with a banana-like odor, documented detectable smell threshold for humans of 0.025 PPM, and a 15 PPB level of quantation limit.

  20. Pavlovian conditioning enhances resistance to disruption of dogs performing an odor discrimination.

    Science.gov (United States)

    Hall, Nathaniel J; Smith, David W; Wynne, Clive D L

    2015-05-01

    Domestic dogs are used to aid in the detection of a variety of substances such as narcotics and explosives. Under real-world detection situations there are many variables that may disrupt the dog's performance. Prior research on behavioral momentum theory suggests that higher rates of reinforcement produce greater resistance to disruption, and that this is heavily influenced by the stimulus-reinforcer relationship. The present study tests the Pavlovian interpretation of resistance to change using dogs engaged in an odor discrimination task. Dogs were trained on two odor discriminations that alternated every six trials akin to a multiple schedule in which the reinforcement probability for a correct response was always 1. Dogs then received several sessions of either odor Pavlovian conditioning to the S+ of one odor discrimination (Pavlovian group) or explicitly unpaired exposure to the S+ of one odor discrimination (Unpaired group). The remaining odor discrimination pair for each dog always remained an unexposed control. Resistance to disruption was assessed under presession feeding, a food-odor disruptor condition, and extinction, with baseline sessions intervening between disruption conditions. Equivalent baseline detection rates were observed across experimental groups and odorant pairs. Under disruption conditions, Pavlovian conditioning led to enhanced resistance to disruption of detection performance compared to the unexposed control odor discrimination. Unpaired odor conditioning did not influence resistance to disruption. These results suggest that changes in Pavlovian contingencies are sufficient to influence resistance to change. © Society for the Experimental Analysis of Behavior.

  1. Reminiscence therapy using odor in alcohol-dependent patients--psychophysiological evaluation and psychological evaluation; power spectral analysis of heart rate variability.

    Science.gov (United States)

    Arizono, H; Morita, N; Iizuka, S; Satoh, S; Nakatani, Y

    2000-12-01

    This research was based on the hypothesis that when alcohol-dependent patients describe themselves, awakening of emotion by affirmative odor stimulation may facilitate memory reframing focusing on more affirmative emotion and memories. To prove the hypothesis, physiological changes accompanied by emotional awakening were evaluated by measuring the autonomic activity. In addition, subjective evaluation by a self-report manner was examined to investigate the effectiveness of Reminiscence Therapy (RT) using odor in alcohol-dependent patients. Thirty-four patients who met the DSM-IV criteria of alcohol-related disorders and were hospitalized in a ward specialized to alcohol dependence therapy. Each patient underwent a one-to-one interview twice. For counterbalance, one interview was performed with odor stimulation using an odor with a relaxing effect that recall pleasant emotion, and the other was without odor stimulation. As the evaluation indices of physiological changes accompanied by emotional awakening, index of autonomic function (HRV; Heart rate variability) for objective evaluation and psychological indices (STAI; State-Trait Anxiety Inventory VAS; Visual Analog Scale) for subjective evaluation were measured. 1) Objective evaluation: Regarding the evaluation index of the autonomic function, the sympathetic nervous system activity (LF/HF; low frequency component/high frequency component ratio) was significantly inhibited by odor stimulation (p Subjective evaluation: Compared to the state prior to interview, state anxiety judged by STAI was significantly decreased after interview (p subjective evaluation, but the objective evaluation suggested that the odor inhibited the sympathetic nervous system. Thus, it was suggested that odor can be used in RT, that is, emotional changes due to stimulation of odor may be applicable in RT.

  2. Removal of target odorous molecules on to activated carbon cloths.

    Science.gov (United States)

    Le Leuch, L M; Subrenat, A; Le Cloirec, P

    2004-01-01

    Activated carbon materials are adsorbents whose physico-chemical properties are interesting for the treatment of odorous compounds like hydrogen sulfide. Indeed, their structural parameters (pore structure) and surface chemistry (presence of heteroatoms such as oxygen, hydrogen, nitrogen, sulfur, phosphorus) play an important role in H2S removal. The cloth texture of these adsorbents (activated carbon cloths) is particularly adapted for dealing with high flows, often found in the treatment of odor emissions. Thus, this paper first presents the influence of these parameters through adsorption isothermal curves performed on several materials. Secondly, tests in a dynamic system are described. They highlight the low critical thickness of the fabric compared to granular activated carbon.

  3. Internal Representation and Memory Formation of Odor Preference Based on Oscillatory Activities in a Terrestrial Slug

    Science.gov (United States)

    Sekiguchi, Tatsuhiko; Furudate, Hiroyuki; Kimura, Tetsuya

    2010-01-01

    The terrestrial slug "Limax" exhibits a highly developed ability to learn odors with a small nervous system. When a fluorescent dye, Lucifer Yellow (LY), is injected into the slug's body cavity after odor-taste associative conditioning, a group of neurons in the procerebral (PC) lobe, an olfactory center of the slug, is labeled by LY. We examined…

  4. The smell of age: perception and discrimination of body odors of different ages.

    Directory of Open Access Journals (Sweden)

    Susanna Mitro

    Full Text Available Our natural body odor goes through several stages of age-dependent changes in chemical composition as we grow older. Similar changes have been reported for several animal species and are thought to facilitate age discrimination of an individual based on body odors, alone. We sought to determine whether humans are able to discriminate between body odor of humans of different ages. Body odors were sampled from three distinct age groups: Young (20-30 years old, Middle-age (45-55, and Old-age (75-95 individuals. Perceptual ratings and age discrimination performance were assessed in 41 young participants. There were significant differences in ratings of both intensity and pleasantness, where body odors from the Old-age group were rated as less intense and less unpleasant than body odors originating from Young and Middle-age donors. Participants were able to discriminate between age categories, with body odor from Old-age donors mediating the effect also after removing variance explained by intensity differences. Similarly, participants were able to correctly assign age labels to body odors originating from Old-age donors but not to body odors originating from other age groups. This experiment suggests that, akin to other animals, humans are able to discriminate age based on body odor alone and that this effect is mediated mainly by body odors emitted by individuals of old age.

  5. The smell of age: perception and discrimination of body odors of different ages.

    Science.gov (United States)

    Mitro, Susanna; Gordon, Amy R; Olsson, Mats J; Lundström, Johan N

    2012-01-01

    Our natural body odor goes through several stages of age-dependent changes in chemical composition as we grow older. Similar changes have been reported for several animal species and are thought to facilitate age discrimination of an individual based on body odors, alone. We sought to determine whether humans are able to discriminate between body odor of humans of different ages. Body odors were sampled from three distinct age groups: Young (20-30 years old), Middle-age (45-55), and Old-age (75-95) individuals. Perceptual ratings and age discrimination performance were assessed in 41 young participants. There were significant differences in ratings of both intensity and pleasantness, where body odors from the Old-age group were rated as less intense and less unpleasant than body odors originating from Young and Middle-age donors. Participants were able to discriminate between age categories, with body odor from Old-age donors mediating the effect also after removing variance explained by intensity differences. Similarly, participants were able to correctly assign age labels to body odors originating from Old-age donors but not to body odors originating from other age groups. This experiment suggests that, akin to other animals, humans are able to discriminate age based on body odor alone and that this effect is mediated mainly by body odors emitted by individuals of old age.

  6. Scent marking behavior as an odorant communication in mice

    Science.gov (United States)

    Arakawa, Hiroyuki; Blanchard, D. Caroline; Arakawa, Keiko; Dunlap, Christopher; Blanchard, Robert J.

    2008-01-01

    In rodents, where chemical signals play a particularly important role in determining intraspecies interactions including social dominance and intersexual relationships, various studies have shown that behavior is sensitive to conspecific odor cues. Mice use urinary scent marks for communication with individual conspecifics in many social contexts. Urinary scent involves genetic information about individuals such as species, sex, and individual identity as well as metabolic information such as social dominance, and reproductive and health status, which are mediated by chemical proteins in scent marks including the major histocompatibility complex and the major urinary proteins. The odor of the predator which can be considered to be a threatening signal for the prey also modulate mouse behavior in which scent marking is suppressed in response to the cat odor exposure in mice. These odorant chemicals are detected and recognized through two olfactory bulbs, the role of which in detection of chemosignals with biological relevant appears to be differential, but partly overlapped. Mice deposit scent marks toward conspecifics to maintain their social relationships, and inhibit scent marking in a context where natural predator, cat odor is contained. This suppression of scent marking is long-lasting (for at least 7 days) and context-dependent, while the odorant signaling to conspecifics tends to appear frequently (over 24 hrs but less than 7 days intervals) depending on the familiarity of each signal-recipient. It has been discussed that scent marking is a communicative behavior associated with territoriality toward conspecifics, indicating that the social signaling within species are sensitive to predator odor cues in terms of vulnerability to predation risk. PMID:18565582

  7. Crossmodal effect of music and odor pleasantness on olfactory quality perception

    Directory of Open Access Journals (Sweden)

    Carlos eVelasco

    2014-11-01

    Full Text Available Previous research has demonstrated that ratings of the perceived pleasantness and quality of odors can be modulated by auditory stimuli presented at around the same time. Here, we extend these results by assessing whether the hedonic congruence between odor and sound stimuli can modulate the perception of odor intensity, pleasantness, and quality in untrained participants. Unexpectedly, our results reveal that broadband white noise, which was rated as unpleasant in a follow-up experiment, actually had a more pronounced effect on participants’ odor ratings than either the consonant or dissonant musical selections. In particular, participants rated the six smells used as being less pleasant and less sweet when they happened to be listening to white noise, as compared to any one of the other music conditions. What is more, these results also add evidence to the existence a close relationship between an odor’s hedonic character and the perception of odor quality. So, for example, independent of the sound condition, pleasant odors were rated as sweeter, less dry, and brighter than the unpleasant odors. These results are discussed in terms of their implications for the understanding of crossmodal correspondences between olfactory and auditory stimuli.

  8. DoOR 2.0 - Comprehensive Mapping of Drosophila melanogaster Odorant Responses

    Science.gov (United States)

    Münch, Daniel; Galizia, C. Giovanni

    2016-02-01

    Odors elicit complex patterns of activated olfactory sensory neurons. Knowing the complete olfactome, i.e. the responses in all sensory neurons for all relevant odorants, is desirable to understand olfactory coding. The DoOR project combines all available Drosophila odorant response data into a single consensus response matrix. Since its first release many studies were published: receptors were deorphanized and several response profiles were expanded. In this study, we add unpublished data to the odor-response profiles for four odorant receptors (Or10a, Or42b, Or47b, Or56a). We deorphanize Or69a, showing a broad response spectrum with the best ligands including 3-hydroxyhexanoate, alpha-terpineol, 3-octanol and linalool. We include all of these datasets into DoOR, provide a comprehensive update of both code and data, and new tools for data analyses and visualizations. The DoOR project has a web interface for quick queries (http://neuro.uni.kn/DoOR), and a downloadable, open source toolbox written in R, including all processed and original datasets. DoOR now gives reliable odorant-responses for nearly all Drosophila olfactory responding units, listing 693 odorants, for a total of 7381 data points.

  9. Pleasant and unpleasant odors influence hedonic evaluations of human faces: an event-related potential study.

    Directory of Open Access Journals (Sweden)

    Stephanie Jane Cook

    2015-12-01

    Full Text Available Odors can alter hedonic evaluations of human faces, but the neural mechanisms of such effects are poorly understood. The present study aimed to analyze the neural underpinning of odor-induced changes in evaluations of human faces in an odor-priming paradigm, using event-related potentials (ERPs. Healthy, young participants (N = 20 rated neutral faces presented after a three second pulse of a pleasant odor (jasmine, unpleasant odor (methylmercaptan, or no-odor control (clean air. Neutral faces presented in the pleasant odor condition were rated more pleasant than the same faces presented in the no-odor control condition, which in turn were rated more pleasant than faces in the unpleasant odor condition. Analysis of face-related potentials revealed four clusters of electrodes significantly affected by odor condition at specific time points during long-latency epochs (600−950 ms. In the 620−640 ms interval, two scalp-time clusters showed greater negative potential in the right parietal electrodes in response to faces in the pleasant odor condition, compared to those in the no-odor and unpleasant odor conditions. At 926 ms, face-related potentials showed greater positivity in response to faces in the pleasant and unpleasant odor conditions at the left and right lateral frontal-temporal electrodes, respectively. Our data shows that odor-induced shifts in evaluations of faces were associated with amplitude changes in the late (> 600 and ultra-late (> 900 ms latency epochs. The observed amplitude changes during the ultra-late epoch are consistent with a left/right hemisphere bias towards pleasant/unpleasant odor effects. Odors alter evaluations of human faces, even when there is a temporal lag between presentation of odors and faces. Our results provide an initial understanding of the neural mechanisms underlying effects of odors on hedonic evaluations.

  10. Postnatal odorant exposure induces peripheral olfactory plasticity at the cellular level.

    Science.gov (United States)

    Cadiou, Hervé; Aoudé, Imad; Tazir, Bassim; Molinas, Adrien; Fenech, Claire; Meunier, Nicolas; Grosmaitre, Xavier

    2014-04-02

    Mammalian olfactory sensory neurons (OSNs) form the primary elements of the olfactory system. Inserted in the olfactory mucosa lining of the nasal cavity, they are exposed to the environment and their lifespan is brief. Several reports say that OSNs are regularly regenerated during the entire life and that odorant environment affects the olfactory epithelium. However, little is known about the impact of the odorant environment on OSNs at the cellular level and more precisely in the context of early postnatal olfactory exposure. Here we exposed MOR23-green fluorescent protein (GFP) and M71-GFP mice to lyral or acetophenone, ligands for MOR23 or M71, respectively. Daily postnatal exposure to lyral induces plasticity in the population of OSNs expressing MOR23. Their density decreases after odorant exposure, whereas the amount of MOR23 mRNA and protein remain stable in the whole epithelium. Meanwhile, quantitative PCR indicates that each MOR23 neuron has higher levels of olfactory receptor transcripts and also expresses more CNGA2 and phosphodiesterase 1C, fundamental olfactory transduction pathway proteins. Transcript levels return to baseline after 4 weeks recovery. Patch-clamp recordings reveal that exposed MOR23 neurons respond to lyral with higher sensitivity and broader dynamic range while the responses' kinetics were faster. These effects are specific to the odorant-receptor pair lyral-MOR23: there was no effect of acetophenone on MOR23 neurons and no effect of acetophenone and lyral on the M71 population. Together, our results clearly demonstrate that OSNs undergo specific anatomical, molecular, and functional adaptation when chronically exposed to odorants in the early stage of life.

  11. [Actinobacteria and their odor-producing capacities in a surface water in Shanghai].

    Science.gov (United States)

    Chen, Jiao; Bai, Xiao-hui; Lu, Ning; Wang, Xian-yun; Zhang, Yong-hui; Wu, Pan-cheng; Guo, Xin-chi

    2014-10-01

    The odor in raw water is one of the main sources of odor in drinking water. The occurrence of actinobacteria and their odor producing capacities in a reservoir in.Shanghai were investigated. Gauze's medium and membrane filtration were used for actinobacteria isolation. Through combined methods of 16S rRNA sequencing, colony and hyphae morphology, carbon source utilization, physiological and biochemical characteristics, 40 strains of actinobacteria were identified from the reservoir. Results showed that there were 38 Streptomyces, an Aeromicrobium and a Pseudonocardia. Liquid culture medium and the real reservoir water were used to test the odor producing capacity of these 40 strains of actinobacteria, and headspace solid phase microextraction (HS-SPME) and high resolution gas chromatography mass spectroscopy (GC/MS) were used to analyze the odor compounds 2-methylisoborneol (2-MIB) and geosmin (GSM) in the fermentation liquor. The test results showed that, the odor-producing capacities of these actinobacteria in different fermentation media showed different variation trends, even within the genera Streptomyces. The odor-producing capacity of actinobacteria in the liquid culture medium could not represent their states in the reservoir water or their actual odor contribution to the aquatic environment.

  12. Recruits of the stingless bee Scaptotrigona pectoralis learn food odors from the nest atmosphere

    Science.gov (United States)

    Reichle, Christian; Jarau, Stefan; Aguilar, Ingrid; Ayasse, Manfred

    2010-05-01

    The ability to learn food odors inside the nest and to associate them with food sources in the field is of essential importance for the recruitment of nestmates in social bees. We investigated odor learning by workers within the hive and the influence of these odors on their food choice in the field in the stingless bee Scaptotrigona pectoralis. During the experiments, recruited bees had to choose between two feeders, one with an odor that was present inside the nest during the recruitment process, and one with an unknown odor. In all experiments with different odor combinations (linalool/phenylacetaldehyde, geraniol/eugenol) a significant majority of bees visited the feeder with the odor they had experienced in their nest ( χ 2-tests; p bees showed no preference for one of two feeders when they were either baited with the same odor (linalool) or contained no odor. Our results clearly show that naïve workers of S. pectoralis can learn the odor of a food source during the recruitment process from the nest atmosphere and that their subsequent food search in the field is influenced by the learned odor.

  13. GC-MS analysis of off-odor volatiles from irradiated pork

    International Nuclear Information System (INIS)

    Lin Ruotai; Geng Shengrong; Zhang Jinmu; Chen Yuxia; Liu Yangmin; Wang Liping; Wang Hong; Xu Ying; Yao Side

    2007-01-01

    The main compounds of off-odor volatiles from irradiated refrigerated vacuum-packaged pork were analyzed by gas chromatograph/mass spectrometer (GC-MS). The analytical results showed that the main compounds of off-odor volatiles were dimethyl disulfide, dimethyl sulfide, dimethyl trisulfide, S-methyl thioacetate, and methanethiol. It was proved that the off-odor volatile came from irradiated S-containing amino acid and thiamin. (authors)

  14. The Enantioselectivity of Odor Sensation: Some Examples for Undergraduate Chemistry Courses

    Science.gov (United States)

    Kraft, Philip; Mannschreck, Albrecht

    2010-01-01

    This article discusses seven chiral odorants that demonstrate the enantioselectivity of odor sensation: carvone, Celery Ketone, camphor, Florhydral, 3-methyl-3-sulfanylhexan-1-ol, muscone, and methyl jasmonate. After a general introduction of the odorant-receptor interaction and the combinatorial code of olfaction, the olfactory properties of the…

  15. Changes in Olfactory Sensory Neuron Physiology and Olfactory Perceptual Learning After Odorant Exposure in Adult Mice.

    Science.gov (United States)

    Kass, Marley D; Guang, Stephanie A; Moberly, Andrew H; McGann, John P

    2016-02-01

    The adult olfactory system undergoes experience-dependent plasticity to adapt to the olfactory environment. This plasticity may be accompanied by perceptual changes, including improved olfactory discrimination. Here, we assessed experience-dependent changes in the perception of a homologous aldehyde pair by testing mice in a cross-habituation/dishabituation behavioral paradigm before and after a week-long ester-odorant exposure protocol. In a parallel experiment, we used optical neurophysiology to observe neurotransmitter release from olfactory sensory neuron (OSN) terminals in vivo, and thus compared primary sensory representations of the aldehydes before and after the week-long ester-odorant exposure in individual animals. Mice could not discriminate between the aldehydes during pre-exposure testing, but ester-exposed subjects spontaneously discriminated between the homologous pair after exposure, whereas home cage control mice cross-habituated. Ester exposure did not alter the spatial pattern, peak magnitude, or odorant-selectivity of aldehyde-evoked OSN input to olfactory bulb glomeruli, but did alter the temporal dynamics of that input to make the time course of OSN input more dissimilar between odorants. Together, these findings demonstrate that odor exposure can induce both physiological and perceptual changes in odor processing, and suggest that changes in the temporal patterns of OSN input to olfactory bulb glomeruli could induce differences in odor quality. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Odors Bias Time Perception in Visual and Auditory Modalities.

    Science.gov (United States)

    Yue, Zhenzhu; Gao, Tianyu; Chen, Lihan; Wu, Jiashuang

    2016-01-01

    Previous studies have shown that emotional states alter our perception of time. However, attention, which is modulated by a number of factors, such as emotional events, also influences time perception. To exclude potential attentional effects associated with emotional events, various types of odors (inducing different levels of emotional arousal) were used to explore whether olfactory events modulated time perception differently in visual and auditory modalities. Participants were shown either a visual dot or heard a continuous tone for 1000 or 4000 ms while they were exposed to odors of jasmine, lavender, or garlic. Participants then reproduced the temporal durations of the preceding visual or auditory stimuli by pressing the spacebar twice. Their reproduced durations were compared to those in the control condition (without odor). The results showed that participants produced significantly longer time intervals in the lavender condition than in the jasmine or garlic conditions. The overall influence of odor on time perception was equivalent for both visual and auditory modalities. The analysis of the interaction effect showed that participants produced longer durations than the actual duration in the short interval condition, but they produced shorter durations in the long interval condition. The effect sizes were larger for the auditory modality than those for the visual modality. Moreover, by comparing performance across the initial and the final blocks of the experiment, we found odor adaptation effects were mainly manifested as longer reproductions for the short time interval later in the adaptation phase, and there was a larger effect size in the auditory modality. In summary, the present results indicate that odors imposed differential impacts on reproduced time durations, and they were constrained by different sensory modalities, valence of the emotional events, and target durations. Biases in time perception could be accounted for by a framework of

  17. Body Odor Trait Disgust Sensitivity Predicts Perception of Sweat Biosamples.

    Science.gov (United States)

    Liuzza, Marco Tullio; Olofsson, Jonas K; Sabiniewicz, Agnieszka; Sorokowska, Agnieszka

    2017-07-01

    Body odors are potent triggers of disgust and regulate social behaviors in many species. The role of olfaction in disgust-associated behaviors has received scant attention in the research literature, in part because olfactory disgust assessments have required laboratory testing with odors. We have devised the "Body Odor Disgust Scale" (BODS) to facilitate research on olfactory disgust. In this study, we evaluated whether individual differences in BODS scores would be associated with the perception of disgust for sweat samples in a laboratory setting. Results show that BODS was a strong predictor of disgust ratings of sweat samples even when controlling for general disgust sensitivity. In contrast, odor intensity ratings were unrelated to BODS scores. Our findings suggest that the BODS scores reflect body odor disgust perception. The BODS scale might facilitate research on olfactory disgust responses and associated behaviors. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Maternal status regulates cortical responses to the body odor of newborns

    Directory of Open Access Journals (Sweden)

    Johan N Lundström

    2013-09-01

    Full Text Available Studies in non-human mammals have identified olfactory signals as prime mediators of mother-infant bonding and they have been linked with maternal attitudes and behavior in our own species as well. However, although the neuronal network processing infant cues has been studied for visual and auditory signals; to date, no such information exists for chemosensory signals. We contrasted the cerebral activity underlying the processing of infant odor properties in 15 women newly given birth for the first time and 15 women not given birth while smelling the body odor of unfamiliar 2 day-old newborn infants. Maternal status-dependent activity was demonstrated in the thalamus when exposed to the body odor of a newly born infant. Subsequent regions of interest analyses indicated that dopaminergic neostriatal areas are active in maternal-dependent responses. Taken together, these data suggests that body odors from 2 day-old newborns elicit activation in reward-related cerebral areas in women, regardless of their maternal status. These tentative data suggests that certain body odors might act as a catalyst for bonding mechanisms and highlights the need for future research on odor-dependent mother-infant bonding using parametric designs controlling for biological saliency and general odor perception effects.

  19. Sensory Preconditioning in Newborn Rabbits: From Common to Distinct Odor Memories

    Science.gov (United States)

    Coureaud, Gerard; Tourat, Audrey; Ferreira, Guillaume

    2013-01-01

    This study evaluated whether olfactory preconditioning is functional in newborn rabbits and based on joined or independent memory of odorants. First, after exposure to odorants A+B, the conditioning of A led to high responsiveness to odorant B. Second, responsiveness to B persisted after amnesia of A. Third, preconditioning was also functional…

  20. Identification and quantification of glue-like off-odors in elastic therapeutic tapes.

    Science.gov (United States)

    Denk, Philipp; Buettner, Andrea

    2018-05-01

    Elastic therapeutic tapes are an important tool in the field of physical therapy and medicine. These tapes contain types of adhesive. However, sensory evaluations revealed the release of pronounced and irritating odors of the tapes. Negative odors were, amongst others, reported in elastic therapeutic tapes containing acrylic adhesives. In this study, the odor of four different tape samples was evaluated applying a descriptive analysis approach carried out by a trained sensory panel. Afterwards, the volatile compounds were recovered from the samples by solvent extraction and isolated by solvent-assisted flavor evaporation (SAFE). The obtained distillates were subsequently analyzed by gas chromatography-olfactometry (GC-O) and two-dimensional GC-O coupled with mass spectrometry (2D-GC-MS/O). To determine the most potent odorants in the distillates, odor extract dilution analyses (OEDA) were carried out. Thirty-one odorants were successfully identified using this approach, which were all described for the first time as odorants in tapes. Amongst the set of volatiles, unsaturated and saturated aldehydes were present, eliciting fatty, soapy, and citrus-like odor impressions, as well as a range of glue-like, moldy, and fruity smelling odor-active volatiles, such as 2-ethyl-1-hexanol, butyl benzoate, and 3-phenyltoluene. Based on their relative intensities, the concentrations of the glue-like smelling substances were determined: 2-ethyl-1-hexanol, present in all samples, was determined with concentrations ranging from 10 to 200 mg/kg in the investigated tapes.

  1. A conserved aspartic acid is important for agonist (VUAA1 and odorant/tuning receptor-dependent activation of the insect odorant co-receptor (Orco.

    Directory of Open Access Journals (Sweden)

    Brijesh N Kumar

    Full Text Available Insect odorant receptors function as heteromeric odorant-gated cation channels comprising a conventional odorant-sensitive tuning receptor, and a conserved co-receptor (Orco. An Orco agonist, VUAA1, is able to activate both heteromeric and homomeric Orco-containing channels. Very little is known about specific residues in Orco that contribute to cation permeability and gating. We investigated the importance of two conserved Asp residues, one in each of transmembrane domains 5 and 7, for channel function by mutagenesis. Drosophila melanogaster Orco and its substitution mutants were expressed in HEK cells and VUAA1-stimulated channel activity was determined by Ca(2+ influx and whole-cell patch clamp electrophysiology. Substitution of D466 in transmembrane 7 with amino acids other than glutamic acid resulted in a substantial reduction in channel activity. The D466E Orco substitution mutant was ~2 times more sensitive to VUAA1. The permeability of the D466E Orco mutant to cations was unchanged relative to wild-type Orco. When D466E Orco is co-expressed with a conventional tuning odorant receptor, the heteromeric complex also shows increased sensitivity to an odorant. Thus, the effect of the D466E mutation is not specific to VUAA1 agonism or dependent on homomeric Orco assembly. We suggest the gain-of-activation characteristic of the D466E mutant identifies an amino acid that is likely to be important for activation of both heteromeric and homomeric insect odorant receptor channels.

  2. Olfactory habituation in Drosophila-odor encoding and its plasticity in the antennal lobe.

    Science.gov (United States)

    Twick, Isabell; Lee, John Anthony; Ramaswami, Mani

    2014-01-01

    A ubiquitous feature of an animal's response to an odorant is that it declines when the odorant is frequently or continuously encountered. This decline in olfactory response, termed olfactory habituation, can have temporally or mechanistically different forms. The neural circuitry of the fruit fly Drosophila melanogaster's olfactory system is well defined in terms of component cells, which are readily accessible to functional studies and genetic manipulation. This makes it a particularly useful preparation for the investigation of olfactory habituation. In addition, the insect olfactory system shares many architectural and functional similarities with mammalian olfactory systems, suggesting that olfactory mechanisms in insects may be broadly relevant. In this chapter, we discuss the likely mechanisms of olfactory habituation in context of the participating cell types, their connectivity, and their roles in sensory processing. We overview the structure and function of key cell types, the mechanisms that stimulate them, and how they transduce and process odor signals. We then consider how each stage of olfactory processing could potentially contribute to behavioral habituation. After this, we overview a variety of recent mechanistic studies that point to an important role for potentiation of inhibitory synapses in the primary olfactory processing center, the antennal lobe, in driving the reduced response to familiar odorants. Following the discussion of mechanisms for short- and long-term olfactory habituation, we end by considering how these mechanisms may be regulated by neuromodulators, which likely play key roles in the induction, gating, or suppression of habituated behavior, and speculate on the relevance of these processes for other forms of learning and memory. © 2014 Elsevier B.V. All rights reserved.

  3. Flavor, fragrance, and odor analysis

    National Research Council Canada - National Science Library

    Marsili, Ray

    2012-01-01

    ...)-olfactometry, and electronic-nose technology, this new edition discusses the significant advantage of these methods for flavor and odor studies in the food, cosmetic, and pharmaceutical industries...

  4. Evaluation of γ-radiation on green tea odor volatiles

    International Nuclear Information System (INIS)

    Fanaro, G.B.; Duarte, R.C.; Araujo, M.M.; Purgatto, E.; Villavicencio, A.L.C.H.

    2011-01-01

    The aim of this study was to evaluate the gamma radiation effects on green tea odor volatiles in green tea at doses of 0, 5, 10, 15 and 20 kGy. The volatile organic compounds were extracted by hydrodistillation and analyzed by GC/MS. The green tea had a large influence on radiation effects, increasing the identified volatiles in relation to control samples. The dose of 10 kGy was responsible to form the majority of new odor compounds following by 5 and 20 kGy. However, the dose of 5 kGy was the dose that degraded the majority of volatiles in non-irradiated samples, following by 20 kGy. The dose of 15 kGy showed has no effect on odor volatiles. The gamma radiation, at dose up to 20 kGy, showed statistically no difference between irradiated and non irradiated green tea on odors compounds.

  5. Assessing implicit odor localization in humans using a cross-modal spatial cueing paradigm.

    Science.gov (United States)

    Moessnang, Carolin; Finkelmeyer, Andreas; Vossen, Alexandra; Schneider, Frank; Habel, Ute

    2011-01-01

    Navigation based on chemosensory information is one of the most important skills in the animal kingdom. Studies on odor localization suggest that humans have lost this ability. However, the experimental approaches used so far were limited to explicit judgements, which might ignore a residual ability for directional smelling on an implicit level without conscious appraisal. A novel cueing paradigm was developed in order to determine whether an implicit ability for directional smelling exists. Participants performed a visual two-alternative forced choice task in which the target was preceded either by a side-congruent or a side-incongruent olfactory spatial cue. An explicit odor localization task was implemented in a second experiment. No effect of cue congruency on mean reaction times could be found. However, a time by condition interaction emerged, with significantly slower responses to congruently compared to incongruently cued targets at the beginning of the experiment. This cueing effect gradually disappeared throughout the course of the experiment. In addition, participants performed at chance level in the explicit odor localization task, thus confirming the results of previous research. The implicit cueing task suggests the existence of spatial information processing in the olfactory system. Response slowing after a side-congruent olfactory cue is interpreted as a cross-modal attentional interference effect. In addition, habituation might have led to a gradual disappearance of the cueing effect. It is concluded that under immobile conditions with passive monorhinal stimulation, humans are unable to explicitly determine the location of a pure odorant. Implicitly, however, odor localization seems to exert an influence on human behaviour. To our knowledge, these data are the first to show implicit effects of odor localization on overt human behaviour and thus support the hypothesis of residual directional smelling in humans. © 2011 Moessnang et al.

  6. Assessing implicit odor localization in humans using a cross-modal spatial cueing paradigm.

    Directory of Open Access Journals (Sweden)

    Carolin Moessnang

    Full Text Available Navigation based on chemosensory information is one of the most important skills in the animal kingdom. Studies on odor localization suggest that humans have lost this ability. However, the experimental approaches used so far were limited to explicit judgements, which might ignore a residual ability for directional smelling on an implicit level without conscious appraisal.A novel cueing paradigm was developed in order to determine whether an implicit ability for directional smelling exists. Participants performed a visual two-alternative forced choice task in which the target was preceded either by a side-congruent or a side-incongruent olfactory spatial cue. An explicit odor localization task was implemented in a second experiment.No effect of cue congruency on mean reaction times could be found. However, a time by condition interaction emerged, with significantly slower responses to congruently compared to incongruently cued targets at the beginning of the experiment. This cueing effect gradually disappeared throughout the course of the experiment. In addition, participants performed at chance level in the explicit odor localization task, thus confirming the results of previous research.The implicit cueing task suggests the existence of spatial information processing in the olfactory system. Response slowing after a side-congruent olfactory cue is interpreted as a cross-modal attentional interference effect. In addition, habituation might have led to a gradual disappearance of the cueing effect. It is concluded that under immobile conditions with passive monorhinal stimulation, humans are unable to explicitly determine the location of a pure odorant. Implicitly, however, odor localization seems to exert an influence on human behaviour. To our knowledge, these data are the first to show implicit effects of odor localization on overt human behaviour and thus support the hypothesis of residual directional smelling in humans.

  7. Genetic influences on human body odor: from genes to the axillae.

    Science.gov (United States)

    Preti, George; Leyden, James J

    2010-02-01

    Several groups have identified the characteristic axillary odorants and how they arrive on the skin surface, pre-formed, bound to water-soluble odorless precursors in apocrine secretions. In the current issue, Martin et al., (2010) describe the relationship between the production of axillary odorants and variants in the ABCC11 gene. Individuals who are homozygotic for a SNP (538G>A) were found to have significantly less of the characteristic axillary odorants than either individuals who were heterozygotic for this change or those who had the wild-type gene. The 538G>A SNP predominates in Asians who have nearly complete loss of typical body odor. ABCC11 is expressed and localized in apocrine sweat glands. These findings are remarkably similar to the ethnic distribution and expression patterns for apocrine apoD, a previously identified carrier of a characteristic axillary odorant.

  8. The link between odors and illness : how health cognitions affect odor perception

    NARCIS (Netherlands)

    Bulsing, P.J.

    2009-01-01

    Some people report health effects after exposure to relatively low levels of odorous chemicals, levels which are often well tolerated by the majority of the population. The research in this thesis was aimed at investigating the role of cognitive influences in this phenomenon. Could it be possible

  9. Preference for human body odors is influenced by gender and sexual orientation.

    Science.gov (United States)

    Martins, Yolanda; Preti, George; Crabtree, Christina R; Runyan, Tamar; Vainius, Aldona A; Wysocki, Charles J

    2005-09-01

    Human body odor may contribute to selection of partners. If so, sexual orientation may influence preference for and perhaps production of human body odors. In a test of these hypotheses, heterosexual and homosexual males and females made two-alternative forced-choice preference judgments for body odors obtained from other heterosexual and homosexual males and females. Subjects chose between odors from (a) heterosexual males and gay males, (b) heterosexual males and heterosexual females, (c) heterosexual females and lesbians, and (d) gay males and lesbians. Results indicate that differences in body odor are detected and responded to on the basis of, in part, an individual's gender and sexual orientation. Possible mechanisms underlying these findings are discussed.

  10. Canine olfactory receptor gene polymorphism and its relation to odor detection performance by sniffer dogs.

    Science.gov (United States)

    Lesniak, Anna; Walczak, Marta; Jezierski, Tadeusz; Sacharczuk, Mariusz; Gawkowski, Maciej; Jaszczak, Kazimierz

    2008-01-01

    The outstanding sensitivity of the canine olfactory system has been acknowledged by using sniffer dogs in military and civilian service for detection of a variety of odors. It is hypothesized that the canine olfactory ability is determined by polymorphisms in olfactory receptor (OR) genes. We investigated 5 OR genes for polymorphic sites which might affect the olfactory ability of service dogs in different fields of specific substance detection. All investigated OR DNA sequences proved to have allelic variants, the majority of which lead to protein sequence alteration. Homozygous individuals at 2 gene loci significantly differed in their detection skills from other genotypes. This suggests a role of specific alleles in odor detection and a linkage between single-nucleotide polymorphism and odor recognition efficiency.

  11. The orexin-1 receptor antagonist SB-334867 decreases anxiety-like behavior and c-Fos expression in the hypothalamus of rats exposed to cat odor.

    Science.gov (United States)

    Vanderhaven, M W; Cornish, J L; Staples, L G

    2015-02-01

    Increasing evidence suggests that the orexin system is involved in modulating anxiety, and we have recently shown that cat odor-induced anxiety in rats is attenuated by the orexin receptor antagonist SB-334867. In the current experiment, c-Fos expression was used to map changes in neuronal activation following SB-334867 administration in the cat odor anxiety model. Male Wistar rats were exposed to cat odor with or without SB-334867 pre-treatment (10 mg/kg, i.p.). A naïve control group not exposed to cat odor was also used. Following cat odor exposure, brains were processed for c-Fos expression. Vehicle-treated rats showed an increase in anxiety-like behaviors (increased hiding and decreased approach toward the cat odor), and increased c-Fos expression in the posteroventral medial amygdala (MePV), paraventricular hypothalamus (PVN) and dorsal premammillary nucleus (PMd). In rats pretreated with SB-334867, approach scores increased and c-Fos expression decreased in the PVN and PMd. These results provide both behavioral and neuroanatomical evidence for the attenuation of cat odor-induced anxiety in rats via the orexin system. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  12. Taste and odor recognition memory: the emotional flavor of life.

    Science.gov (United States)

    Miranda, Maria Isabel

    2012-01-01

    In recent years, our knowledge of the neurobiology of taste and smell has greatly increased; by using several learning models, we now have a better understanding of the behavioral and neurochemical basis of memory recognition. Studies have provided new evidence of some processes that depend on prior experience with the specific combination of sensory stimuli. This review contains recent research related to taste and odor recognition memory, and the goal is to highlight the role of two prominent brain structures, the insular cortex and the amygdala. These structures have an important function during learning and memory and have been associated with the differences in learning induced by the diverse degrees of emotion during taste/odor memory formation, either aversive or appetitive or when taste and odor are combined and/or potentiated.Therefore, this review includes information about certain neurochemical transmitters and their interactions during appetitive or aversive taste memory formation,taste-potentiated odor aversion memory, and conditioned odor aversion, which might be able to maintain the complex processes necessary for flavor recognition memory.

  13. Long-term memory for odors: influences of familiarity and identification across 64 days.

    Science.gov (United States)

    Cornell Kärnekull, Stina; Jönsson, Fredrik U; Willander, Johan; Sikström, Sverker; Larsson, Maria

    2015-05-01

    Few studies have investigated long-term odor recognition memory, although some early observations suggested that the forgetting rate of olfactory representations is slower than for other sensory modalities. This study investigated recognition memory across 64 days for high and low familiar odors and faces. Memory was assessed in 83 young participants at 4 occasions; immediate, 4, 16, and 64 days after encoding. The results indicated significant forgetting for odors and faces across the 64 days. The forgetting functions for the 2 modalities were not fundamentally different. Moreover, high familiar odors and faces were better remembered than low familiar ones, indicating an important role of semantic knowledge on recognition proficiency for both modalities. Although odor recognition was significantly better than chance at the 64 days testing, memory for the low familiar odors was relatively poor. Also, the results indicated that odor identification consistency across sessions, irrespective of accuracy, was positively related to successful recognition. © The Author 2015. Published by Oxford University Press.

  14. Food-Related Odors Activate Dopaminergic Brain Areas

    OpenAIRE

    Agnieszka Sorokowska; Agnieszka Sorokowska; Katherina Schoen; Cornelia Hummel; Pengfei Han; Jonathan Warr; Thomas Hummel

    2017-01-01

    Food-associated cues of different sensory categories have often been shown to be a potent elicitor of cerebral activity in brain reward circuits. Smells influence and modify the hedonic qualities of eating experience, and in contrast to smells not associated with food, perception of food-associated odors may activate dopaminergic brain areas. In this study, we aimed to verify previous findings related to the rewarding value of food-associated odors by means of an fMRI design involving careful...

  15. Do trained dogs discriminate individual body odors of women better than those of men?

    Science.gov (United States)

    Jezierski, Tadeusz; Sobczyńska, Magdalena; Walczak, Marta; Gorecka-Bruzda, Aleksandra; Ensminger, John

    2012-05-01

    Scent identification lineups using dogs are a potentially valuable forensic tool, but have been dismissed by some critics because of cases where a false identification was shown to have occurred. It is not known, however, why dogs appear to make more false indications to the odors of some persons than of others. In this study, human genders were compared as to the degree their individual odors are distinguishable or "attractive" to dogs. Six dogs were trained to smell an individual's hand odor sample and then find the matching hand odor sample in a lineup of five odors. Using one-gender lineups and two-gender lineups with different gender ratios, it was found that dogs trained for the study identified individual women's hand odors more accurately than those of men. It is hypothesized that this is either because of differences in chemical compounds making discrimination of women's odors easier, or because of greater "odor attractiveness" of women's scents to dogs. © 2012 American Academy of Forensic Sciences.

  16. FCC riser quick separation system: a review

    Directory of Open Access Journals (Sweden)

    Zhi Li

    2016-10-01

    Full Text Available Abstract The riser reactor is the key unit in the fluid catalytic cracking (FCC process. As the FCC feedstocks become heavier, the product mixture of oil, gas and catalysts must be separated immediately at the outlet of the riser to avoid excessive coking. The quick separation system is the core equipment in the FCC unit. China University of Petroleum (Beijing has developed many kinds of separation system including the fender-stripping cyclone and circulating-stripping cyclone systems, which can increase the separation efficiency and reduce the pressure drop remarkably. For the inner riser system, a vortex quick separation system has been developed. It contains a vortex quick separator and an isolated shell. In order to reduce the separation time, a new type of separator called the short residence time separator system was developed. It can further reduce the separation time to less than 1 s. In this paper, the corresponding design principles, structure and industrial application of these different kinds of separation systems are reviewed. A system that can simultaneously realize quick oil gas separation, quick oil gas extraction and quick pre-stripping of catalysts at the end of the riser is the trend in the future.

  17. Does gently clearing the nasal passage affect odor identification?

    Directory of Open Access Journals (Sweden)

    Mitchell G. Spring

    2014-12-01

    Full Text Available Identifying scents in a wine’s bouquet is considered one of the most important steps in the process of wine tasting. An individual’s ability to successfully do this is dependent on the sense of smell; thus, altering the nasal microenvironment could have a powerful effect on the wine tasting experience. In the present study, we examined olfactory performance in healthy participants who cleared their nasal cavity before odorant presentations. Fifty undergraduate participants were assessed with a standardized test of olfaction requiring the recognition of a battery of odors. Half of these participants cleared mucus from their nasal cavities (by gently blowing their noses prior to the assessment. No difference was found in performance between those who cleared their nasal passages and those who did not. Further, data were not different than known population data from the test. These data suggest that gently clearing the nasal cavity before presentation of odorants bears no effect on the ability to perceive those odor qualities.

  18. Investigation about Role of Algae in Kazeroon Sasan Spring Odor

    Directory of Open Access Journals (Sweden)

    A Hamzeian

    2016-05-01

    Full Text Available Introduction: As odor for potable water is unpleasant for costumers, it needs to do researches for finding the reasons of odorous water. Sasan spring that is located in, near kazeroon city, Fars, Iran, is potable water resource for Kazeroon and Booshehr city and many other villages. Water in Sasan spring has the odor problem. With regards to important   role of algae on ado r problems in this study the role of algae on   odor was investigated. Methods: After regular sampling, the TON (threshold odor number was indicated and algae species was distinguished and the number of total algae and any species  of algae was numbers by microscopic direct numbering method .as the algae mass  is related to nitrogen and phosphor concentration, results of concentration Of nitrogen and phosphor in this spring that was examined regularity by water company was investigated and compared to concentration of these component that are need for algae growing.   Results: results shows that TON was in range  of 4.477 to 6.2 that indicated  oderous limit . Regression and diagram between TON and number of total algae showed the linear relationship. The concentration of nitrogen and phosphor, showed adequate condition for algal grow. Result of determination of algae species showed high population of Oscilatoria and Microcystis species, which are known as essential case of mold odor in water resources. Investigation on geological maps in the region around the Sasan spring, show alluvium source and is effected by surface part of it’s around land. Conclusion: because of the algae was determined as the essential cause of odor   in the spring, and algal growth is related to nutrients, and because of the surface pollution can penetrate in the alluvium lands around the spring, and effect the water in spring, so nutrient control and management is the essential way for odor control in the spring.

  19. Odors bias time perception in visual and auditory modalities

    Directory of Open Access Journals (Sweden)

    Zhenzhu eYue

    2016-04-01

    Full Text Available Previous studies have shown that emotional states alter our perception of time. However, attention, which is modulated by a number of factors, such as emotional events, also influences time perception. To exclude potential attentional effects associated with emotional events, various types of odors (inducing different levels of emotional arousal were used to explore whether olfactory events modulated time perception differently in visual and auditory modalities. Participants were shown either a visual dot or heard a continuous tone for 1000 ms or 4000 ms while they were exposed to odors of jasmine, lavender, or garlic. Participants then reproduced the temporal durations of the preceding visual or auditory stimuli by pressing the spacebar twice. Their reproduced durations were compared to those in the control condition (without odor. The results showed that participants produced significantly longer time intervals in the lavender condition than in the jasmine or garlic conditions. The overall influence of odor on time perception was equivalent for both visual and auditory modalities. The analysis of the interaction effect showed that participants produced longer durations than the actual duration in the short interval condition, but they produced shorter durations in the long interval condition. The effect sizes were larger for the auditory modality than those for the visual modality. Moreover, by comparing performance across the initial and the final blocks of the experiment, we found odor adaptation effects were mainly manifested as longer reproductions for the short time interval later in the adaptation phase, and there was a larger effect size in the auditory modality. In summary, the present results indicate that odors imposed differential impacts on reproduced time durations, and they were constrained by different sensory modalities, valence of the emotional events, and target durations. Biases in time perception could be accounted for by a

  20. Categorical dimensions of human odor descriptor space revealed by non-negative matrix factorization

    Energy Technology Data Exchange (ETDEWEB)

    Chennubhotla, Chakra [University of Pittsburgh School of Medicine, Pittsburgh PA; Castro, Jason [Bates College

    2013-01-01

    In contrast to most other sensory modalities, the basic perceptual dimensions of olfaction remain un- clear. Here, we use non-negative matrix factorization (NMF) - a dimensionality reduction technique - to uncover structure in a panel of odor profiles, with each odor defined as a point in multi-dimensional descriptor space. The properties of NMF are favorable for the analysis of such lexical and perceptual data, and lead to a high-dimensional account of odor space. We further provide evidence that odor di- mensions apply categorically. That is, odor space is not occupied homogenously, but rather in a discrete and intrinsically clustered manner. We discuss the potential implications of these results for the neural coding of odors, as well as for developing classifiers on larger datasets that may be useful for predicting perceptual qualities from chemical structures.

  1. Activated charcoal and baking soda to reduce odor associated with extensive blistering disorders.

    Science.gov (United States)

    Chakravarthi, Arun; Srinivas, C R; Mathew, Anil C

    2008-01-01

    Skin disease leading to extensive blistering and loss of skin is associated with a characteristic smell. Odor can cause physiologic disturbances such as increase in heart rate and respiratory rate. It can also cause nausea and vomiting and is disturbing to bystanders. To test odor reducing capability of activated charcoal. In this blinded experimental study we used putrefied amniotic membrane to produce odor and studied the effectiveness of activated charcoal and soda-bi-carbonate to reduce odor. Statistical analysis with Kruskal Wall's Chi Square Test and Man Whitney U test showed significant reduction of odor using activated charcoal by itself or along with soda-bi-carbonate. We recommend the usage of activated charcoal with/without soda bicarbonate as an inexpensive practical measure to reduce foul odor associated with extensive skin loss.

  2. Activation analysis of selenium in odorous vegetable foods

    International Nuclear Information System (INIS)

    Suzuki, Shogo; Hirai, Shoji; Noda, Katsuhiko.

    1981-01-01

    The selenium in odorous vegetables was analyzed by nondestructive neutron activation analysis using 75 Se, by the γ-ray coincidence method with a Ge(Li) and a NaI(Tl) detectors of definite energy ranges. By means of the coincidence counting, the background spectrum in 75 Se in the vicinity of 265 KeV was able to be reduced to about 1/20 of that by the former detector alone, so that the 75 Se detection sensitivity was raised over fourfold. Thus the selenium in odorous vegetables was able to be determined down to the content as low as 0.02 μg/g. The selenium content in garlic bulbs was 0.02 - 0.31 μg/g, and in onion bulbs 0.02 - 0.05 μg/g, both of which agreed well with those by fluorometry. In other odorous vegetables, the selenium content was as little as 0.1 μg/g or lower. It has been said that the selenium content is relatively large along with sulfur because of the same group, but it was found to be fairly small in the odorous vegetables. (Mori, K.)

  3. Relationship between 3-Methyl-2,4-nonanedione Concentration and Intensity of Light-induced Off-odor in Soy Bean Oil.

    Science.gov (United States)

    Sano, Takashi; Iwahashi, Maiko; Imagi, Jun; Sato, Toshiro; Yamashita, Toshiyuki; Fukusaki, Eiichiro; Bamba, Takeshi

    2016-05-01

    A beany and green off-odor is developed in soy bean oil (SBO) under light-induced oxidative conditions. 3-Methyl-2,4-nonanedione (3-MND) was inferred as the compound responsible for the off-odor. In this study, we designed a simple quantification method for 3-MND in SBO, and evaluated the relationship between the 3-MND concentration and the intensity of the off-odor. 3-MND was analyzed by GC/MS with a thermal desorption unit system. By our method, the 3-MND concentration was found to increase with storage days and the SBO content under light exposure, and there was a high correlation between the measured 3-MND concentration and the intensity of the light-induced off-odor in SBO (R = 0.9586).

  4. Aversive olfactory associative memory loses odor specificity over time.

    Science.gov (United States)

    König, Christian; Antwi-Adjei, Emmanuel; Ganesan, Mathangi; Kilonzo, Kasyoka; Viswanathan, Vignesh; Durairaja, Archana; Voigt, Anne; Yarali, Ayse

    2017-05-01

    Avoiding associatively learned predictors of danger is crucial for survival. Aversive memories can, however, become counter-adaptive when they are overly generalized to harmless cues and contexts. In a fruit fly odor-electric shock associative memory paradigm, we found that learned avoidance lost its specificity for the trained odor and became general to novel odors within a day of training. We discuss the possible neural circuit mechanisms of this effect and highlight the parallelism to over-generalization of learned fear behavior after an incubation period in rodents and humans, with due relevance for post-traumatic stress disorder. © 2017. Published by The Company of Biologists Ltd.

  5. Sea floor separation system; Havbunnsseparasjonssystem

    Energy Technology Data Exchange (ETDEWEB)

    Hatlo, Andreas; Skaranger, Jon

    1998-07-01

    This presentation describes work done by an alliance of Kongsberg Offshore a.s. (KOS) and Aker Maritime (AMA). The alliance comprises the development and delivery of seafloor separation systems. The alliance was established as an answer to the identified need of seafloor separation and processing in the oil industry. In several fields on the Norwegian shelf there is defined a potential need for seafloor separation and pumping. The same trend can be seen in international waters as well, especially on deeper waters. Calculation of the economic potential for the relevant applications is based on a large number of variables, including both OPEX and CAPEX assessments. In order to be able to identify and analyse this potential in a better way, KOS and AMA are developing a tool for cost-benefit evaluations of such a seafloor separation and pumping system. PROSERNAT (France) and ALSTOME (UK) are important subcontractors in the development of seafloor separation and pumping systems. PROSERNAT will supply the separation tank and internal arrangement, ALSTOME will supply the power electronics for the distribution of seafloor power distribution.

  6. Characterization of an enantioselective odorant receptor in the yellow fever mosquito Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Jonathan D Bohbot

    2009-09-01

    Full Text Available Enantiomers differ only in the left or right handedness (chirality of their orientations and exhibit identical chemical and physical properties. In chemical communication systems, enantiomers can be differentially active at the physiological and behavioral levels. Only recently were enantioselective odorant receptors demonstrated in mammals while their existence in insects has remained hypothetical. Using the two-microelectrode voltage clamp of Xenopus oocytes, we show that the yellow fever mosquito, Aedes aegypti, odorant receptor 8 (AaOR8 acts as a chiral selective receptor for the (R-(--enantiomer of 1-octen-3-ol, which in the presence of other kairomones is an attractant used by blood-sucking insects to locate their hosts. In addition to steric constraints, chain length and degree of unsaturation play important roles in this recognition process. This is the first characterization of an enantioselective odorant receptor in insects and the results demonstrate that an OR alone, without helper proteins, can account for chiral specificity exhibited by olfactory sensory neurons (OSNs.

  7. How Far Does a Receptor Influence Vibrational Properties of an Odorant?

    Science.gov (United States)

    Reese, Anna; List, Nanna Holmgaard; Kongsted, Jacob; Solov'yov, Ilia A

    2016-01-01

    The biophysical mechanism of the sense of smell, or olfaction, is still highly debated. The mainstream explanation argues for a shape-based recognition of odorant molecules by olfactory receptors, while recent investigations suggest the primary olfactory event to be triggered by a vibrationally-assisted electron transfer reaction. We consider this controversy by studying the influence of a receptor on the vibrational properties of an odorant in atomistic details as the coupling between electronic degrees of freedom of the receptor and the vibrations of the odorant is the key parameter of the vibrationally-assisted electron transfer. Through molecular dynamics simulations we elucidate the binding specificity of a receptor towards acetophenone odorant. The vibrational properties of acetophenone inside the receptor are then studied by the polarizable embedding density functional theory approach, allowing to quantify protein-odorant interactions. Finally, we judge whether the effects of the protein provide any indications towards the existing theories of olfaction.

  8. Quantum Calculation for Musk Molecules Infrared Spectra towards the Understanding of Odor

    Directory of Open Access Journals (Sweden)

    Elaine Rose Maia

    2014-01-01

    Full Text Available It is not clear so far how humans can recognize odor. One of the theories regarding structure-odor relationship is vibrational theory, which claims that odors can be recognized by their modes of vibration. In this sense, this paper brings a novel comparison made between musky and nonmusky molecules, as to check the existence of correlation between their modes on the infrared spectra and odor. For this purpose, sixteen musky odorants were chosen, as well as seven other molecules that are structurally similar to them, but with no musk odor. All of them were submitted to solid theoretical methodology (using molecular mechanics/molecular dynamics and Neglect of Diatomic Differential Overlap Austin Model 1 methods to optimize geometries as to achieve density functional theory spectra information, with both Gradient Corrected Functional Perdew-Wang generalized-gradient approximation (GGA/PW91 and hybrid Becke, three-parameter, Lee-Yang-Parr (B3LYP functional. For a proper analysis over spectral data, a mathematical method was designed, generating weighted averages for theoretical frequencies and computing deviations from these averages. It was then devised that musky odorants satisfied demands of the vibrational theory, while nonmusk compounds belonging either to nitro group or to acyclic group failed to fulfill the same criteria.

  9. Activated charcoal and baking soda to reduce odor associated with extensive blistering disorders

    Directory of Open Access Journals (Sweden)

    Chakravarthi Arun

    2008-01-01

    Full Text Available Background: Skin disease leading to extensive blistering and loss of skin is associated with a characteristic smell. Odor can cause physiologic disturbances such as increase in heart rate and respiratory rate. It can also cause nausea and vomiting and is disturbing to bystanders. Aims: To test odor reducing capability of activated charcoal. Methods: In this blinded experimental study we used putrefied amniotic membrane to produce odor and studied the effectiveness of activated charcoal and soda-bi-carbonate to reduce odor. Results: Statistical analysis with Kruskal Wall′s Chi Square Test and Man Whitney U test showed significant reduction of odor using activated charcoal by itself or along with soda-bi-carbonate. Conclusion: We recommend the usage of activated charcoal with/without soda bicarbonate as an inexpensive practical measure to reduce foul odor associated with extensive skin loss.

  10. Odorant receptors directly activate phospholipase C/inositol-1,4,5-trisphosphate coupled to calcium influx in Odora cells.

    Science.gov (United States)

    Liu, Guang; Badeau, Robert M; Tanimura, Akihiko; Talamo, Barbara R

    2006-03-01

    Mechanisms by which odorants activate signaling pathways in addition to cAMP are hard to evaluate in heterogeneous mixtures of primary olfactory neurons. We used single cell calcium imaging to analyze the response to odorant through odorant receptor (OR) U131 in the olfactory epithelial cell line Odora (Murrell and Hunter 1999), a model system with endogenous olfactory signaling pathways. Because adenylyl cyclase levels are low, agents activating cAMP formation do not elevate calcium, thus unmasking independent signaling mediated by OR via phospholipase C (PLC), inositol-1,4,5-trisphosphate (IP(3)), and its receptor. Unexpectedly, we found that extracellular calcium is required for odor-induced calcium elevation without the release of intracellular calcium, even though the latter pathway is intact and can be stimulated by ATP. Relevant signaling components of the PLC pathway and G protein isoforms are identified by western blot in Odora cells as well as in olfactory sensory neurons (OSNs), where they are localized to the ciliary zone or cell bodies and axons of OSNs by immunohistochemistry. Biotinylation studies establish that IP(3) receptors type 2 and 3 are at the cell surface in Odora cells. Thus, individual ORs are capable of elevating calcium through pathways not directly mediated by cAMP and this may provide another avenue for odorant signaling in the olfactory system.

  11. Flavor, fragrance, and odor analysis

    National Research Council Canada - National Science Library

    Marsili, Ray

    2012-01-01

    ... solid-phase micro extraction procedures. It also presents important updates on GC-olfactometry as a tool for studying flavor synergy effects"-- "Sample preparation techniques for isolating and concentrating flavor and odor-active chemicals...

  12. High hunger state increases olfactory sensitivity to neutral but not food odors.

    Science.gov (United States)

    Stafford, Lorenzo D; Welbeck, Kimberley

    2011-01-01

    Understanding how hunger state relates to olfactory sensitivity has become more urgent due to their possible role in obesity. In 2 studies (within-subjects: n = 24, between-subjects: n = 40), participants were provided with lunch before (satiated state) or after (nonsatiated state) testing and completed a standardized olfactory threshold test to a neutral odor (Experiments 1 and 2) and discrimination test to a food odor (Experiment 2). Experiment 1 revealed that olfactory sensitivity was greater in the nonsatiated versus satiated state, with additionally increased sensitivity for the low body mass index (BMI) compared with high BMI group. Experiment 2 replicated this effect for neutral odors, but in the case of food odors, those in a satiated state had greater acuity. Additionally, whereas the high BMI group had higher acuity to food odors in the satiated versus nonsatiated state, no such differences were found for the low BMI group. The research here is the first to demonstrate how olfactory acuity changes as a function of hunger state and relatedness of odor to food and that BMI can predict differences in olfactory sensitivity.

  13. Reshaping of bulbar odor response by nasal flow rate in the rat.

    Directory of Open Access Journals (Sweden)

    Emmanuelle Courtiol

    2011-01-01

    Full Text Available The impact of respiratory dynamics on odor response has been poorly studied at the olfactory bulb level. However, it has been shown that sniffing in the behaving rodent is highly dynamic and varies both in frequency and flow rate. Bulbar odor response could vary with these sniffing parameter variations. Consequently, it is necessary to understand how nasal airflow can modify and shape odor response at the olfactory bulb level.To assess this question, we used a double cannulation and simulated nasal airflow protocol on anesthetized rats to uncouple nasal airflow from animal respiration. Both mitral/tufted cell extracellular unit activity and local field potentials (LFPs were recorded. We found that airflow changes in the normal range were sufficient to substantially reorganize the response of the olfactory bulb. In particular, cellular odor-evoked activities, LFP oscillations and spike phase-locking to LFPs were strongly modified by nasal flow rate.Our results indicate the importance of reconsidering the notion of odor coding as odor response at the bulbar level is ceaselessly modified by respiratory dynamics.

  14. Characterization of odorants in inflatable aquatic toys and swimming learning devices-which substances are causative for the characteristic odor and potentially harmful?

    Science.gov (United States)

    Wiedmer, Christoph; Velasco-Schön, Cristina; Buettner, Andrea

    2017-06-01

    Based on the observation of intense and offensive smells in the product group of aquatic toys, four representative products were exemplarily chosen and sensorially characterized by an expert panel. Panellists reported mostly almond- and rubber-like notes for three of the four samples, whereas the smell of the fourth sample was dominated by organic solvent-associated notes such as "nail polish-like." To elucidate the molecular reasons of these smells, we isolated the volatile fraction of the product by solvent extraction and high vacuum distillation, and identified the main odorants by aroma extract dilution analysis (AEDA), followed by one- and two-dimensional gas chromatography, with parallel mass spectrometric and olfactometric detection. Additionally, the materials of the samples were identified by means of differential scanning calorimetry (DSC), attenuated total reflectance spectroscopy (ATR-spectroscopy), and Beilstein halogen test. Between 32 and 46 odors could be detected in each sample by means of AEDA, whereby five to 13 of these compounds were detectable with by far the highest dilution factors, and were found to primarily correlate with the smells of the respective products. Focussing the subsequent identification on these causative substances led to the successful identification of the majority of these odorants. Among them were several mono- or di-unsaturated carbonyl compounds and their epoxidized derivatives, which are typical odorous artefacts from fatty acid oxidation, but also odor-active organic solvents such as cyclohexanone, isophorone, and phenol.

  15. The odorant receptor co-receptor from the bed bug, Cimex lectularius L.

    Directory of Open Access Journals (Sweden)

    Immo A Hansen

    Full Text Available Recently, the bed bug, Cimex lectularius L. has re-emerged as a serious and growing problem in many parts of the world. Presence of resistant bed bugs and the difficulty to eliminate them has renewed interest in alternative control tactics. Similar to other haematophagous arthropods, bed bugs rely on their olfactory system to detect semiochemicals in the environment. Previous studies have morphologically characterized olfactory organs of bed bugs' antenna and have physiologically evaluated the responses of olfactory receptor neurons (ORNs to host-derived chemicals. To date, odorant binding proteins (OBPs and odorant receptors (ORs associated with these olfaction processes have not been studied in bed bugs. Chemoreception in insects requires formation of heteromeric complexes of ORs and a universal OR coreceptor (Orco. Orco is the constant chain of every odorant receptor in insects and is critical for insect olfaction but does not directly bind to odorants. Orco agonists and antagonists have been suggested as high-value targets for the development of novel insect repellents. In this study, we have performed RNAseq of bed bug sensory organs and identified several odorant receptors as well as Orco. We characterized Orco expression and investigated the effect of chemicals targeting Orco on bed bug behavior and reproduction. We have identified partial cDNAs of six C. lectularius OBPs and 16 ORs. Full length bed bug Orco was cloned and sequenced. Orco is widely expressed in different parts of the bed bug including OR neurons and spermatozoa. Treatment of bed bugs with the agonist VUAA1 changed bed bug pheromone-induced aggregation behavior and inactivated spermatozoa. We have described and characterized for the first time OBPs, ORs and Orco in bed bugs. Given the importance of these molecules in chemoreception of this insect they are interesting targets for the development of novel insect behavior modifiers.

  16. Cross-adaptation between olfactory responses induced by two subgroups of odorant molecules.

    Science.gov (United States)

    Takeuchi, Hiroko; Imanaka, Yukie; Hirono, Junzo; Kurahashi, Takashi

    2003-09-01

    It has long been believed that vertebrate olfactory signal transduction is mediated by independent multiple pathways (using cAMP and InsP3 as second messengers). However, the dual presence of parallel pathways in the olfactory receptor cell is still controversial, mainly because of the lack of information regarding the single-cell response induced by odorants that have been shown to produce InsP3 exclusively (but not cAMP) in the olfactory cilia. In this study, we recorded activities of transduction channels of single olfactory receptor cells to InsP3-producing odorants. When the membrane potential was held at -54 mV, application of InsP3-producing odorants to the ciliary region caused an inward current. The reversal potential was 0 +/- 7 mV (mean +/- SD, n = 10). Actually, InsP3-producing odorants generated responses in a smaller fraction of cells (lilial, 3.4%; lyral, 1.7%) than the cAMP-producing odorant (cineole, 26%). But, fundamental properties of responses were surprisingly homologous; namely, spatial distribution of the sensitivity, waveforms, I-V relation, and reversal potential, dose dependence, time integration of stimulus period, adaptation, and recovery. By applying both types of odorants alternatively to the same cell, furthermore, we observed cells to exhibit symmetrical cross-adaptation. It seems likely that even with odorants with different modalities adaptation occurs completely depending on the amount of current flow. The data will also provide evidence showing that olfactory response generation and adaptation are regulated by a uniform mechanism for a wide variety of odorants.

  17. Measurement of the odor impact of a waste deposit using the SF6-tracer method

    International Nuclear Information System (INIS)

    Roetzer, H.; Muehldorf, V.; Riesing, J.

    1994-12-01

    Landfill gas emitted from a waste deposit often causes odor nuisance in the vicinity. For a new sanitary landfill to be established in an area where also other sources of odor existed, very low limits for additional odor nuisance were given by local authorities. To verify that the odor concentrations were below these limit values, the odor contributions of different sources had to be distinguished. Olfactometric methods, using human observers to estimate the intensity of odors, were not applicable to this problem. For direct measurements by analytical methods concentrations of odorous substances were too small. Therefore a tracer method was applied to measure the odor impact of the sanitary landfill to its environment. The emitted landfill gas was labelled with the tracer gas SF 6 . The tracer gas was parted to even amounts and released through ten special nozzles equally distributed over the surface of the landfill. In the area around the landfill the concentration of the tracer gas was measured by collecting air samples and analysing them with a gas chromatograph with an electron capture detector. Fifteen air sampling units were used to collect eight consecutive air samples at each selected point. These measurements gave the relation between the emission of landfill gas and the resulting concentrations in ambient air. With these transmission coefficients the concentrations of odorous gases at the sampling points were evaluated, using the emission concentrations measured by analytical techniques at the landfiIl site. The resulting odor concentrations were compared with values of odor thresholds to establish the odor impact of the waste deposit on the environment. (author)

  18. Character impact odorants of fennel fruits and fennel tea.

    Science.gov (United States)

    Zeller, Annette; Rychlik, Michael

    2006-05-17

    The flavor of fennel fruits and fennel tea was examined by aroma extract dilution analysis of the respective dichloromethane extracts. In both fennel fruits and tea, trans-anethole, anisaldehyde, and trans-4,5-epoxy-2(E)-decenal showed high flavor dilution (FD) factors followed by fenchone, 1,8-cineole, (R)-alpha-pinene, estragole, and beta-myrcene. On the basis of these results, the odorants showing higher FD factors were quantified in tea as well as in fruits, and odor activity values (OAV) in tea were calculated by dividing the concentration of the compound by its recognition threshold in water. The highest OAV was found for trans-anethole, followed by estragole, fenchone, 1,8-cineole, (R)-alpha-pinene, beta-myrcene, and anisaldehyde. From a comparison of the concentrations of odorants in fruits and tea, trans-anethole and estragole showed similar extraction rates of approximately 10-15%, whereas the extraction rates for (R)-alpha-pinene, beta-myrcene, and limonene were below 2%. In contrast to this, fenchone, camphor, linalool, and carvone showed higher extraction rates (26-50%), whereas the high apparent extraction rates of anisalcohol (393%) and vanilline (480%) were attributed to the formation from precursors. Sensory studies of aqueous models containing odorants in the amounts quantified in fennel teas revealed high similarity of the models with the tea and proved that all impact odorants had been identified in their correct concentrations. Further sensory experiments showed that estragole had no odor impact on the overall flavor of fennel tea, and, therefore, a reduction of estragole in fennel products would have no negative impact on their sensoric quality. In contrast to this, trans-anethole and fenchone were found to be character impact compounds of fennel.

  19. Problems in instrumentation for S-odorant emissions

    International Nuclear Information System (INIS)

    Hall, H.J.

    1974-01-01

    Instrumentation to measure sulfur-containing odorants in stack emissions is much more difficult than in the ambient atmosphere, and must be matched to the specific source: key components aside from H 2 S are methyl mercaptan in paper mills, COS/CS 2 in a refinery Claus plant, and SO 2 /SO 3 in a combustion stack. Satisfactory operation for a period of six months was not achieved by any instrument in this service, in a lab and field evaluation of eight instruments of three types commercially available as of 1971. The effects of interferent gases H 2 O, SO 2 , CO 2 /CO and particulates which are diluted in ambient samples are greatly aggravated in stack gases, where the ratio of odorant to interferent may be 1:1000 or less, due to the very great sensitivity of human receptors to S-odorants. The most serious problem proved to be the analysis for odorless carbonyl sulfide, which is commonly formed where S compounds are oxidized in a reducing atmosphere. This COS has been undetected or mistaken for odorous H 2 S in most analyses. A field instrument for the general case would provide exactly simultaneous readings at five minute intervals or less for the five components H 2 S, SO 2 , COS, CSH, and total S, or their equivalent. This may be simplified to four components or less only when the composition of the sample gas is positively known

  20. Combinations of two odorants of smell identification test for screening of olfactory impairment.

    Science.gov (United States)

    Shiga, Hideaki; Yamamoto, Junpei; Kitamura, Miwa; Nakagawa, Hideaki; Matsubasa, Tomoko; Seo, Atsuko; Miwa, Takaki

    2014-12-01

    To determine whether combinations of two odorants of the Open Essence smell identification test can be used to screen for olfactory impairment in Japanese people. A total of 243 Japanese subjects (142 males, 101 females; mean age, 37.5 years; age range, 20-62 years) were enrolled in the study. The main outcome measures were the results of olfactory testing by using the full 12 odorants (condensed milk, cooking gas, curry, cypress wood (Japanese cypress, hinoki), India ink, Japanese orange (mikan), menthol, perfume, roasted garlic, rose, sweaty-smelling clothes, and wood) of the Open Essence test as well as combinations of two odorants of the Open Essence test, and the results of self-reported questionnaires addressing awareness of a smell disorder, history of sinunasal disease, self-reported nasal obstruction, and history of smoking. In screening with combinations of two odorants, the highest positive likelihood ratio (19.1) was obtained with the cypress wood and India ink odorants. All subjects correctly identified the curry odorant. Combinations of other odorants also had high positive likelihood ratios (India ink and sweaty-smelling clothes, 17.6; perfume and sweaty-smelling clothes, 14.7; cypress wood and roasted garlic, 14.1; cypress wood and rose, 13.2; cypress wood and perfume, 11.0; cypress wood and wood, 10.7). The combination of cypress wood and India ink odorants may be useful for detecting individuals with olfactory impairment among subjects who can correctly identify the curry odorant. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  1. Context odor presentation during sleep enhances memory in honeybees.

    Science.gov (United States)

    Zwaka, Hanna; Bartels, Ruth; Gora, Jacob; Franck, Vivien; Culo, Ana; Götsch, Moritz; Menzel, Randolf

    2015-11-02

    Sleep plays an important role in stabilizing new memory traces after learning [1-3]. Here we investigate whether sleep's role in memory processing is similar in evolutionarily distant species and demonstrate that a context trigger during deep-sleep phases improves memory in invertebrates, as it does in humans. We show that in honeybees (Apis mellifera), exposure to an odor during deep sleep that has been present during learning improves memory performance the following day. Presentation of the context odor during wake phases or novel odors during sleep does not enhance memory. In humans, memory consolidation can be triggered by presentation of a context odor during slow-wave sleep that had been present during learning [3-5]. Our results reveal that deep-sleep phases in honeybees have the potential to prompt memory consolidation, just as they do in humans. This study provides strong evidence for a conserved role of sleep-and how it affects memory processes-from insects to mammals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Smell your way back to childhood: autobiographical odor memory.

    Science.gov (United States)

    Willander, Johan; Larsson, Maria

    2006-04-01

    This study addressed age distributions and experiential qualities of autobiographical memories evoked by different sensory cues. Ninety-three older adults were presented with one of three cue types (word, picture, or odor) and were asked to relate any autobiographical event for the given cue. The main aims were to explore whether (1) the age distribution of olfactory-evoked memories differs from memories cued by words and pictures and (2) the experiential qualities of the evoked memories vary over the different cues. The results showed that autobiographical memories triggered by olfactory information were older than memories associated with verbal and visual information. Specifically, most odor-cued memories were located to the first decade of life (memories associated with verbal and visual cues peaked in early adulthood (11-20 years). Also, odor-evoked memories were associated with stronger feelings of being brought back in time and had been thought of less often than memories evoked by verbal and visual information. This pattern of findings suggests that odor-evoked memories may be different from other memory experiences.

  3. Test-retest reliability and validity of the Sniffin' TOM odor memory test.

    Science.gov (United States)

    Croy, Ilona; Zehner, Cora; Larsson, Maria; Zucco, Gesualdo M; Hummel, Thomas

    2015-03-01

    Few attempts have been made to develop an olfactory test that captures episodic retention of olfactory information. Assessment of episodic odor memory is of particular interest in aging and in the cognitively impaired as both episodic memory deficits and olfactory loss have been targeted as reliable hallmarks of cognitive decline and impending dementia. Here, 96 healthy participants (18-92 years) and an additional 19 older people with mild cognitive impairment were tested (73-82 years). Participants were presented with 8 common odors with intentional encoding instructions that were followed by a yes-no recognition test. After recognition completion, participants were asked to identify all odors by means of free or cued identification. A retest of the odor memory test (Sniffin' TOM = test of odor memory) took place 17 days later. The results revealed satisfactory test-retest reliability (0.70) of odor recognition memory. Both recognition and identification performance were negatively affected by age and more pronounced among the cognitively impaired. In conclusion, the present work presents a reliable, valid, and simple test of episodic odor recognition memory that may be used in clinical groups where both episodic memory deficits and olfactory loss are prevalent preclinically such as Alzheimer's disease. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Kinase activity in the olfactory bulb is required for odor memory consolidation.

    Science.gov (United States)

    Tong, Michelle T; Kim, Tae-Young P; Cleland, Thomas A

    2018-05-01

    Long-term fear memory formation in the hippocampus and neocortex depends upon brain-derived neurotrophic factor (BDNF) signaling after acquisition. Incremental, appetitive odor discrimination learning is thought to depend substantially on the differentiation of adult-born neurons within the olfactory bulb (OB)-a process that is closely associated with BDNF signaling. We sought to elucidate the role of neurotrophin signaling within the OB on odor memory consolidation. Male mice were trained on odor-reward associative discriminations after bilateral infusion of the kinase inhibitor K252a, or vehicle control, into the OB. K252a is a partially selective inhibitor of tyrosine kinase (Trk) receptors, including the TrkB receptor for BDNF, though it also inhibits other plasticity-related kinases such as PKC and CaMKII/IV. K252a infusion into the OB did not impair odor acquisition or short-term (2 h) memory for the learned discriminations, but significantly impaired long-term (48 h) odor memory (LTM). This LTM deficit also was associated with reduced selectivity for the conditioned odorant in a reward-seeking digging task. Infusions of K252a immediately prior to testing did not impair LTM recall. These results indicate that kinase activation in the OB is required for the consolidation of odor memory of incrementally acquired information. © 2018 Tong et al.; Published by Cold Spring Harbor Laboratory Press.

  5. 2-Nonenal newly found in human body odor tends to increase with aging.

    Science.gov (United States)

    Haze, S; Gozu, Y; Nakamura, S; Kohno, Y; Sawano, K; Ohta, H; Yamazaki, K

    2001-04-01

    Human body odor consists of various kinds of odor components. Here, we have investigated the changes in body odor associated with aging. The body odor of subjects between the ages of 26 and 75 was analyzed by headspace gas chromatography/mass spectrometry. 2-Nonenal, an unsaturated aldehyde with an unpleasant greasy and grassy odor, was detected only in older subjects (40 y or older). Furthermore, analysis of skin surface lipids revealed that omega7 unsaturated fatty acids and lipid peroxides also increased with aging and that there were positive correlations between the amount of 2-nonenal in body odor and the amount of omega7 unsaturated fatty acids or lipid peroxides in skin surface lipids. 2-Nonenal was generated only when omega7 unsaturated fatty acids were degraded by degradation tests in which some main components of skin surface lipids were oxidatively decomposed using lipid peroxides as initiator of an oxidative chain reaction. The results indicate that 2-nonenal is generated by the oxidative degradation of omega7 unsaturated fatty acids, and suggest that 2-nonenal may be involved in the age-related change of body odor.

  6. The Smell of Age: Perception and Discrimination of Body Odors of Different Ages

    OpenAIRE

    Mitro, Susanna; Gordon, Amy R.; Olsson, Mats J.; Lundström, Johan N.

    2012-01-01

    Our natural body odor goes through several stages of age-dependent changes in chemical composition as we grow older. Similar changes have been reported for several animal species and are thought to facilitate age discrimination of an individual based on body odors, alone. We sought to determine whether humans are able to discriminate between body odor of humans of different ages. Body odors were sampled from three distinct age groups: Young (20-30 years old), Middle-age (45-55), and Old-age (...

  7. Chemical and canine analysis as complimentary techniques for the identification of active odors of the invasive fungus, Raffaelea lauricola.

    Science.gov (United States)

    Simon, Alison G; Mills, DeEtta K; Furton, Kenneth G

    2017-06-01

    Raffaelea lauricola, a fungus causing a vascular wilt (laurel wilt) in Lauraceae trees, was introduced into the United States in the early 2000s. It has devastated forests in the Southeast and has now moved into the commercial avocado groves in southern Florida. Trained detection canines are currently one of the few successful methods for early detection of pre-symptomatic diseased trees. In order to achieve the universal and frequent training required to have successful detection canines, it is desirable to create accessible, safe, and long-lasting training aids. However, identification of odorants and compounds is limited by several factors, including both the availability of chemicals and the need to present chemicals individually and in combination to detection canines. A method for the separation and identification of volatile organic compounds (VOCs) from environmental substances for the creation of such a canine training aid is presented here. Headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) was used to identify the odors present in avocado trees infected with the R. lauricola phytopathogen. Twenty-eight compounds were detected using this method, with nine present in greater than 80% of samples. The majority of these compounds were not commercially available as standard reference materials, and a canine trial was designed to identify the active odors without the need of pure chemical compounds. To facilitate the creation of a canine training aid, the VOCs above R. lauricola were separated by venting a 0.53mm ID solgel-wax gas chromatography column to the atmosphere. Ten minute fractions of the odor profile were collected on cotton gauze in glass vials and presented to the detection canines in a series of field trials. The canines alerted to the VOCs from the vials that correspond to a portion of the chromatogram containing the most volatile species from R. lauricola. This innovative fractionation and collection

  8. Analgesia Is Enhanced by Providing Information regarding Good Outcomes Associated with an Odor: Placebo Effects in Aromatherapy?

    Directory of Open Access Journals (Sweden)

    Yuri Masaoka

    2013-01-01

    Full Text Available No previous report has described whether information regarding an odor used in aromatherapy has placebo effects. We investigated whether placebo analgesia was engendered by verbal information regarding the analgesic effects of an odor. Twelve of 24 subjects were provided with the information that a lavender odor would reduce pain (informed, whereas the other 12 subjects were not (not-informed. Concurrent with respiration recording, the subjects were administered a lavender-odor or no-odor treatment during application of painful stimulation to the forefinger. The subjects reported their experience of pain and its unpleasantness on a visual analogue scale after the painful stimulation. The lavender-odor treatment significantly alleviated pain and unpleasantness compared with the no-odor treatment in the informed (P<0.01 and not-informed groups (P<0.05. The no-odor treatment in the informed group significantly alleviated pain and unpleasantness compared with both the no-odor and lavender-odor treatments in the not-informed group (P<0.05. Rapid and shallow breathing induced by the painful stimulation became slow and deep during the lavender-odor and no-odor treatments in both groups. Information regarding a lavender odor, the lavender odor itself, and slower breathing contributed to reduced perceptions of pain and unpleasantness during painful stimulation, suggesting that placebo effects significantly contribute to analgesia in aromatherapy.

  9. Non-Conscious Effect of Food Odors on Children’s Food Choices Varies by Weight Status

    Directory of Open Access Journals (Sweden)

    Lucile Marty

    2017-05-01

    Full Text Available ObjectiveFood cues are omnipresent in the daily environment and may influence eating behavior even non-consciously. An increased reactivity to food cues, such as food odors, has been shown to be correlated with obesity in children. The objective of this study is to investigate whether the non-conscious influence of food odors on children’s food choices varies by their weight status.MethodsSeventy-four children, of whom 29 were obese, took part in this study. The children performed a food choice intention task presented as a computer game in which 30 pairs of food images (a fatty-sweet food picture vs. a fruit picture successively appeared on the screen. The children had to choose the item “they most wanted to eat at the present moment” for each pair. While performing this task, the children wore a headset in which the microphone foam was odorized with a fruity odor, a fatty-sweet odor or no odor. They performed the intention task three times, one time for each olfactory condition. The odors were non-attentively perceived, i.e., none of the children were aware of the odorization of the microphone foams. The modeled probability is the probability to choose a fruit.ResultsIn children with obesity, the fruity odor increased the likelihood of a fruit to be chosen compared to the no-odor condition [OR (95% CL = 1.42 (1.13–1.78, P = 0.0028], while the fatty-sweet odor had no effect on food choice [OR (95% CL = 1.07 (0.85–1.36, P = 0.55]. In children without obesity, both the fruity and the fatty-sweet odors decreased the likelihood to choose a fruit compared to the no-odor condition [OR (95% CL = 0.76 (0.64–0.90, P = 0.0015, for the fruity odor and OR (95% CL = 0.79 (0.66–0.93, P = 0.0062, for the fatty-sweet odor].ConclusionThe different patterns of results obtained in both groups of children suggest differences in the mental representations activated by non-attentively perceived olfactory cues based on

  10. Detection and Classification of Human Body Odor Using an Electronic Nose

    Directory of Open Access Journals (Sweden)

    Teerakiat Kerdcharoen

    2009-09-01

    Full Text Available An electronic nose (E-nose has been designed and equipped with software that can detect and classify human armpit body odor. An array of metal oxide sensors was used for detecting volatile organic compounds. The measurement circuit employs a voltage divider resistor to measure the sensitivity of each sensor. This E-nose was controlled by in-house developed software through a portable USB data acquisition card with a principle component analysis (PCA algorithm implemented for pattern recognition and classification. Because gas sensor sensitivity in the detection of armpit odor samples is affected by humidity, we propose a new method and algorithms combining hardware/software for the correction of the humidity noise. After the humidity correction, the E-nose showed the capability of detecting human body odor and distinguishing the body odors from two persons in a relative manner. The E-nose is still able to recognize people, even after application of deodorant. In conclusion, this is the first report of the application of an E-nose for armpit odor recognition.

  11. Detection and classification of human body odor using an electronic nose.

    Science.gov (United States)

    Wongchoosuk, Chatchawal; Lutz, Mario; Kerdcharoen, Teerakiat

    2009-01-01

    An electronic nose (E-nose) has been designed and equipped with software that can detect and classify human armpit body odor. An array of metal oxide sensors was used for detecting volatile organic compounds. The measurement circuit employs a voltage divider resistor to measure the sensitivity of each sensor. This E-nose was controlled by in-house developed software through a portable USB data acquisition card with a principle component analysis (PCA) algorithm implemented for pattern recognition and classification. Because gas sensor sensitivity in the detection of armpit odor samples is affected by humidity, we propose a new method and algorithms combining hardware/software for the correction of the humidity noise. After the humidity correction, the E-nose showed the capability of detecting human body odor and distinguishing the body odors from two persons in a relative manner. The E-nose is still able to recognize people, even after application of deodorant. In conclusion, this is the first report of the application of an E-nose for armpit odor recognition.

  12. Two Parallel Pathways Assign Opposing Odor Valences during Drosophila Memory Formation

    Directory of Open Access Journals (Sweden)

    Daisuke Yamazaki

    2018-02-01

    Full Text Available During olfactory associative learning in Drosophila, odors activate specific subsets of intrinsic mushroom body (MB neurons. Coincident exposure to either rewards or punishments is thought to activate extrinsic dopaminergic neurons, which modulate synaptic connections between odor-encoding MB neurons and MB output neurons to alter behaviors. However, here we identify two classes of intrinsic MB γ neurons based on cAMP response element (CRE-dependent expression, γCRE-p and γCRE-n, which encode aversive and appetitive valences. γCRE-p and γCRE-n neurons act antagonistically to maintain neutral valences for neutral odors. Activation or inhibition of either cell type upsets this balance, toggling odor preferences to either positive or negative values. The mushroom body output neurons, MBON-γ5β′2a/β′2mp and MBON-γ2α′1, mediate the actions of γCRE-p and γCRE-n neurons. Our data indicate that MB neurons encode valence information, as well as odor information, and this information is integrated through a process involving MBONs to regulate learning and memory.

  13. Left Posterior Orbitofrontal Cortex Is Associated With Odor-Induced Autobiographical Memory: An fMRI Study

    Directory of Open Access Journals (Sweden)

    Keiko Watanabe

    2018-05-01

    Full Text Available Autobiographical odor memory (AM-odor accompanied by a sense of realism of a specific memory elicits strong emotions. AM-odor differs from memory triggered by other sensory modalities, possibly because olfaction involves a unique sensory process. Here, we examined the orbitofrontal cortex (OFC, using functional magnetic resonance imaging (fMRI to determine which OFC subregions are related to AM-odor. Both AM-odor and a control odor successively increased subjective ratings of comfortableness and pleasantness. Importantly, AM-odor also increased arousal levels and the vividness of memories, and was associated with a deep and slow breathing pattern. fMRI analysis indicated robust activation in the left posterior OFC (L-POFC. Connectivity between the POFC and whole brain regions was estimated using psychophysiological interaction analysis (PPI. We detected several trends in connectivity between L-POFC and bilateral precuneus, bilateral rostral dorsal anterior cingulate cortex (rdACC, and left parahippocampus, which will be useful for targeting our hypotheses for future investigations. The slow breathing observed in AM-odor was correlated with rdACC activation. Odor associated with emotionally significant autobiographical memories was accompanied by slow and deep breathing, possibly involving rdACC processing.

  14. Left Posterior Orbitofrontal Cortex Is Associated With Odor-Induced Autobiographical Memory: An fMRI Study.

    Science.gov (United States)

    Watanabe, Keiko; Masaoka, Yuri; Kawamura, Mitsuru; Yoshida, Masaki; Koiwa, Nobuyoshi; Yoshikawa, Akira; Kubota, Satomi; Ida, Masahiro; Ono, Kenjiro; Izumizaki, Masahiko

    2018-01-01

    Autobiographical odor memory (AM-odor) accompanied by a sense of realism of a specific memory elicits strong emotions. AM-odor differs from memory triggered by other sensory modalities, possibly because olfaction involves a unique sensory process. Here, we examined the orbitofrontal cortex (OFC), using functional magnetic resonance imaging (fMRI) to determine which OFC subregions are related to AM-odor. Both AM-odor and a control odor successively increased subjective ratings of comfortableness and pleasantness. Importantly, AM-odor also increased arousal levels and the vividness of memories, and was associated with a deep and slow breathing pattern. fMRI analysis indicated robust activation in the left posterior OFC (L-POFC). Connectivity between the POFC and whole brain regions was estimated using psychophysiological interaction analysis (PPI). We detected several trends in connectivity between L-POFC and bilateral precuneus, bilateral rostral dorsal anterior cingulate cortex (rdACC), and left parahippocampus, which will be useful for targeting our hypotheses for future investigations. The slow breathing observed in AM-odor was correlated with rdACC activation. Odor associated with emotionally significant autobiographical memories was accompanied by slow and deep breathing, possibly involving rdACC processing.

  15. Odor control in swine buildings: recycle flush vs. automated scraper

    Science.gov (United States)

    A research project was conducted to compare odor concentrations in exhaust of traditional flush barns and barns equipped with automated scrapers. The study was conducted at commercial tunnel-ventilated swine barns in northwest Missouri. Odor samples were collected from the barn exhaust in polyvinyl ...

  16. Development of sulfur- and nitrogen- free hydrogen odorants - An important step toward a safe hydrogen society -

    International Nuclear Information System (INIS)

    Nakamura, N.; Oshikawa, K.; Hasegawa, H.; Le Lay, M.; Iwase, M.; Braun, N.A.; Eilers, J.; Walz, A.; Vogt, M.; Herr, M.

    2006-01-01

    We have developed four sulfur-free and nitrogen-free odorants, which can be effectively used to odorize hydrogen. The odors were described through an olfactory test as alarming, strange, and chemical, giving sense of danger to the person who smells the odor. The safety of the material has been assessed and has been shown to be safe for usage. Testing the stability of odorized hydrogen in 80 MPa pressurized state, it was shown for a period of 13 weeks that the odorant retained its warning odor. Using the odorized hydrogen, FC duration test at 0.2 A/cm 2 was carried out for over 900 h without significant decrease in performance or the detectable degradation of MEA. The outlet of the fuel cell had no warning odor, suggesting deodorization on the catalyst. Use of activated charcoal as an adsorbent showed that the deodorization could be effectively carried out, ensuring that normal operation conditions are not perceived as a hydrogen leakage. (authors)

  17. Floral odor learning within the hive affects honeybees' foraging decisions

    Science.gov (United States)

    Arenas, Andrés; Fernández, Vanesa M.; Farina, Walter M.

    2007-03-01

    Honeybees learn odor cues quickly and efficiently when visiting rewarding flowers. Memorization of these cues facilitates the localization and recognition of food sources during foraging flights. Bees can also use information gained inside the hive during social interactions with successful foragers. An important information cue that can be learned during these interactions is food odor. However, little is known about how floral odors learned in the hive affect later decisions of foragers in the field. We studied the effect of food scent on foraging preferences when this learning is acquired directly inside the hive. By using in-hive feeders that were removed 24 h before the test, we showed that foragers use the odor information acquired during a 3-day stimulation period with a scented solution during a food-choice situation outside the nest. This bias in food preference is maintained even 24 h after the replacement of all the hive combs. Thus, without being previously collected outside by foragers, food odors learned within the hive can be used during short-range foraging flights. Moreover, correct landings at a dual-choice device after replacing the storing combs suggests that long-term memories formed within the colony can be retrieved while bees search for food in the field.

  18. Innate recognition of pheromone and food odors in moths: a common mechanism in the antennal lobe?

    Directory of Open Access Journals (Sweden)

    Joshua P Martin

    2010-09-01

    Full Text Available The survival of an animal often depends on an innate response to a particular sensory stimulus. For an adult male moth, two categories of odors are innately attractive: pheromone released by conspecific females, and the floral scents of certain, often co-evolved, plants. These odors consist of multiple volatiles in characteristic mixtures. Here, we review evidence that both categories of odors are processed as sensory objects, and we suggest a mechanism in the primary olfactory center, the antennal lobe (AL, that encodes the configuration of these mixtures and may underlie recognition of innately attractive odors. In the pheromone system, mixtures of two or three volatiles elicit upwind flight. Peripheral changes are associated with behavioral changes in speciation, and suggest the existence of a pattern recognition mechanism for pheromone mixtures in the AL. Moths are similarly innately attracted to certain floral scents. Though floral scents consist of multiple volatiles that activate a broad array of receptor neurons, only a smaller subset, numerically comparable to pheromone mixtures, is necessary and sufficient to elicit behavior. Both pheromone and floral scent mixtures that produce attraction to the odor source elicit synchronous action potentials in particular populations of output (projection neurons (PNs in the AL. We propose a model in which the synchronous output of a population of PNs encodes the configuration of an innately attractive mixture, and thus comprises an innate mechanism for releasing odor-tracking behavior. The particular example of olfaction in moths may inform the general question of how sensory objects trigger innate responses.

  19. A unique memory process modulated by emotion underpins successful odor recognition and episodic retrieval in humans

    Directory of Open Access Journals (Sweden)

    Anne-Lise eSaive

    2014-06-01

    Full Text Available We behaviorally explore the link between olfaction, emotion and memory by testing the hypothesis that the emotion carried by odors facilitates the memory of specific unique events. To investigate this idea, we used a novel behavioral approach inspired by a paradigm developed by our team to study episodic memory in a controlled and as ecological as possible way in humans. The participants freely explored three unique and rich laboratory episodes; each episode consisted of three unfamiliar odors (What positioned at three specific locations (Where within a visual context (Which context. During the retrieval test, which occurred 24 to 72 hours after the encoding, odors were used to trigger the retrieval of the complex episodes. The participants were proficient in recognizing the target odors among distractors and retrieving the visuospatial context in which they were encountered. The episodic nature of the task generated high and stable memory performances, which were accompanied by faster responses and slower and deeper breathing. Successful odor recognition and episodic memory were not related to differences in odor investigation at encoding. However, memory performances were influenced by the emotional content of the odors, regardless of odor valence, with both pleasant and unpleasant odors generating higher recognition and episodic retrieval than neutral odors. Finally, the present study also suggested that when the binding between the odors and the spatio-contextual features of the episode was successful, the odor recognition and the episodic retrieval collapsed into a unique memory process that began as soon as the participants smelled the odors.

  20. A unique memory process modulated by emotion underpins successful odor recognition and episodic retrieval in humans

    Science.gov (United States)

    Saive, Anne-Lise; Royet, Jean-Pierre; Ravel, Nadine; Thévenet, Marc; Garcia, Samuel; Plailly, Jane

    2014-01-01

    We behaviorally explore the link between olfaction, emotion and memory by testing the hypothesis that the emotion carried by odors facilitates the memory of specific unique events. To investigate this idea, we used a novel behavioral approach inspired by a paradigm developed by our team to study episodic memory in a controlled and as ecological as possible way in humans. The participants freely explored three unique and rich laboratory episodes; each episode consisted of three unfamiliar odors (What) positioned at three specific locations (Where) within a visual context (Which context). During the retrieval test, which occurred 24–72 h after the encoding, odors were used to trigger the retrieval of the complex episodes. The participants were proficient in recognizing the target odors among distractors and retrieving the visuospatial context in which they were encountered. The episodic nature of the task generated high and stable memory performances, which were accompanied by faster responses and slower and deeper breathing. Successful odor recognition and episodic memory were not related to differences in odor investigation at encoding. However, memory performances were influenced by the emotional content of the odors, regardless of odor valence, with both pleasant and unpleasant odors generating higher recognition and episodic retrieval than neutral odors. Finally, the present study also suggested that when the binding between the odors and the spatio-contextual features of the episode was successful, the odor recognition and the episodic retrieval collapsed into a unique memory process that began as soon as the participants smelled the odors. PMID:24936176

  1. Locating a compact odor source using a four-channel insect electroantennogram sensor

    Energy Technology Data Exchange (ETDEWEB)

    Myrick, A J; Baker, T C [Chemical Ecology Laboratory, Department of Entomology, Pennsylvania State University, University Park, PA 16802 (United States)

    2011-03-15

    Here we demonstrate the feasibility of using an array of live insects to detect concentrated packets of odor and infer the location of an odor source ({approx}15 m away) using a backward Lagrangian dispersion model based on the Langevin equation. Bayesian inference allows uncertainty to be quantified, which is useful for robotic planning. The electroantennogram (EAG) is the biopotential developed between the tissue at the tip of an insect antenna and its base, which is due to the massed response of the olfactory receptor neurons to an odor stimulus. The EAG signal can carry tens of bits per second of information with a rise time as short as 12 ms (K A Justice 2005 J. Neurophiol. 93 2233-9). Here, instrumentation including a GPS with a digital compass and an ultrasonic 2D anemometer has been integrated with an EAG odor detection scheme, allowing the location of an odor source to be estimated by collecting data at several downwind locations. Bayesian inference in conjunction with a Lagrangian dispersion model, taking into account detection errors, has been implemented resulting in an estimate of the odor source location within 0.2 m of the actual location.

  2. Locating a compact odor source using a four-channel insect electroantennogram sensor

    International Nuclear Information System (INIS)

    Myrick, A J; Baker, T C

    2011-01-01

    Here we demonstrate the feasibility of using an array of live insects to detect concentrated packets of odor and infer the location of an odor source (∼15 m away) using a backward Lagrangian dispersion model based on the Langevin equation. Bayesian inference allows uncertainty to be quantified, which is useful for robotic planning. The electroantennogram (EAG) is the biopotential developed between the tissue at the tip of an insect antenna and its base, which is due to the massed response of the olfactory receptor neurons to an odor stimulus. The EAG signal can carry tens of bits per second of information with a rise time as short as 12 ms (K A Justice 2005 J. Neurophiol. 93 2233-9). Here, instrumentation including a GPS with a digital compass and an ultrasonic 2D anemometer has been integrated with an EAG odor detection scheme, allowing the location of an odor source to be estimated by collecting data at several downwind locations. Bayesian inference in conjunction with a Lagrangian dispersion model, taking into account detection errors, has been implemented resulting in an estimate of the odor source location within 0.2 m of the actual location.

  3. The role of attention in the localization of odors to the mouth.

    Science.gov (United States)

    Stevenson, Richard J; Mahmut, Mehmet K; Oaten, Megan J

    2011-01-01

    Odors can be perceived as arising from the environment or as part of a flavor located in the mouth. One factor that may dictate where an odor is perceived to be is concurrent gustatory stimulation in the mouth. A taste may impair the ability to attend to an odor, especially if they are perceptually similar. Alternatively, salient mouth-based features of a flavor might command attention at the expense of smell. Experiment 1 and 2, using different stimulus sets, explored the impact of perceptually similar and dissimilar pairings of tastes in the mouth and odors at the nose. In each case, these were followed by judgments of the odor's location (mouth vs. nose). Perceptual similarity had no impact on localization judgments. Experiment 3 then manipulated the salience of the olfactory and gustatory cues and showed that each could independently shift the perceived location of an odorant-salient olfactory cues toward the nose and gustatory cues toward the mouth. These findings suggest that the salient features of a flavor may command attention at the expense of olfaction and, thereby, contribute to oral localization, with implications for flavor binding.

  4. Odor perception in children with autism spectrum disorder and its relationship to food neophobia

    Directory of Open Access Journals (Sweden)

    Anne-Claude eLuisier

    2015-12-01

    Full Text Available Atypical sensory functioning in Autism Spectrum Disorder (ASD has been well documented in the last decade for the visual, tactile and auditory systems, but olfaction in ASD is still understudied. The aim of the present study was to examine whether children with ASD and neuro-typically (NT developed children differed in odor perception, at the cognitive (familiarity and identification ability, sensorimotor (olfactory exploration and affective levels (hedonic evaluation. Because an important function of the sense of smell is its involvement in eating, from food selection to appreciation and recognition, a potential link between odor perception and food neophobia was also investigated. To these ends, 10 children between 6 and 13 years old diagnosed with ASD and 10 NT control children were tested. To compare performance, 16 stimuli were used and food neophobia was assessed by the parents on a short food neophobia scale. Results revealed that (i significant hedonic discrimination between attractive and aversive odors was observed in NT (p=0.005; d=2.378 and ASD children (p=0.042; d=0.941, and (ii hedonic discrimination level was negatively correlated with food neophobia scores in ASD (p=0.007 but not NT children. In conclusion, this study offers new insights into odor perception in ASD children, highlighting a relationship between odor hedonic reactivity and eating behavior. This opens up new perspectives on both (i the role of olfaction in the construction of eating behavior in ASD children, and (ii the measurement and meaning of food neophobia in this population.

  5. Odor Perception in Children with Autism Spectrum Disorder and its Relationship to Food Neophobia.

    Science.gov (United States)

    Luisier, Anne-Claude; Petitpierre, Genevieve; Ferdenzi, Camille; Clerc Bérod, Annick; Giboreau, Agnes; Rouby, Catherine; Bensafi, Moustafa

    2015-01-01

    Atypical sensory functioning in Autism Spectrum Disorder (ASD) has been well documented in the last decade for the visual, tactile and auditory systems, but olfaction in ASD is still understudied. The aim of the present study was to examine whether children with ASD and neuro-typically (NT) developed children differed in odor perception, at the cognitive (familiarity and identification ability), sensorimotor (olfactory exploration) and affective levels (hedonic evaluation). Because an important function of the sense of smell is its involvement in eating, from food selection to appreciation and recognition, a potential link between odor perception and food neophobia was also investigated. To these ends, 10 children between 6 and 13 years old diagnosed with ASD and 10 NT control children were tested. To compare performance, 16 stimuli were used and food neophobia was assessed by the parents on a short food neophobia scale. Results revealed that (i) significant hedonic discrimination between attractive and aversive odors was observed in NT (p = 0.005; d = 2.378) and ASD children (p = 0.042; d = 0.941), and (ii) hedonic discrimination level was negatively correlated with food neophobia scores in ASD (p = 0.007) but not NT children. In conclusion, this study offers new insights into odor perception in ASD children, highlighting a relationship between odor hedonic reactivity and eating behavior. This opens up new perspectives on both (i) the role of olfaction in the construction of eating behavior in ASD children, and (ii) the measurement and meaning of food neophobia in this population.

  6. Discriminating the stimulus elements during human odor-taste learning: a successful analytic stance does not eliminate learning.

    Science.gov (United States)

    Stevenson, Richard J; Mahmut, Mehmet K

    2011-10-01

    Odor "sweetness" may arise from experiencing odors and tastes together, resulting in a flavor memory that is later reaccessed by the odor. Forming a flavor memory may be impaired if the taste and odor elements are apparent during exposure, suggesting that configural processing may underpin learning. Using a new procedure, participants made actual flavor discriminations for one odor-taste pair (e.g., Taste A vs. Odor X-Taste A) and mock discriminations for another (e.g., Odor Y-Taste B vs. Odor Y-Taste B). Participants, who were successful at detecting the actual flavor discriminations, demonstrated equal amounts of learning for both odor-taste pairings. These results suggest that although a capacity to discriminate flavor into its elements may be necessary to support learning, whether participants experience a configural or elemental flavor representation may not.

  7. A review on the neural bases of episodic odor memory: from laboratory-based to autobiographical approaches

    Science.gov (United States)

    Saive, Anne-Lise; Royet, Jean-Pierre; Plailly, Jane

    2014-01-01

    Odors are powerful cues that trigger episodic memories. However, in light of the amount of behavioral data describing the characteristics of episodic odor memory, the paucity of information available on the neural substrates of this function is startling. Furthermore, the diversity of experimental paradigms complicates the identification of a generic episodic odor memory network. We conduct a systematic review of the literature depicting the current state of the neural correlates of episodic odor memory in healthy humans by placing a focus on the experimental approaches. Functional neuroimaging data are introduced by a brief characterization of the memory processes investigated. We present and discuss laboratory-based approaches, such as odor recognition and odor associative memory, and autobiographical approaches, such as the evaluation of odor familiarity and odor-evoked autobiographical memory. We then suggest the development of new laboratory-ecological approaches allowing for the controlled encoding and retrieval of specific multidimensional events that could open up new prospects for the comprehension of episodic odor memory and its neural underpinnings. While large conceptual differences distinguish experimental approaches, the overview of the functional neuroimaging findings suggests relatively stable neural correlates of episodic odor memory. PMID:25071494

  8. A review on the neural bases of episodic odor memory: from laboratory-based to autobiographical approaches

    Directory of Open Access Journals (Sweden)

    Anne-Lise eSaive

    2014-07-01

    Full Text Available Odors are powerful cues that trigger episodic memories. However, in light of the amount of behavioral data describing the characteristics of episodic odor memory, the paucity of information available on the neural substrates of this function is startling. Furthermore, the diversity of experimental paradigms complicates the identification of a generic episodic odor memory network. We conduct a systematic review of the literature depicting the current state of the neural correlates of episodic odor memory in healthy humans by placing a focus on the experimental approaches. Functional neuroimaging data are introduced by a brief characterization of the memory processes investigated. We present and discuss laboratory-based approaches, such as odor recognition and odor associative memory, and autobiographical approaches, such as the evaluation of odor familiarity and odor-evoked autobiographical memory. We then suggest the development of new laboratory-ecological approaches allowing for the controlled encoding and retrieval of specific multidimensional events that could open up new prospects for the comprehension of episodic odor memory and its neural underpinnings. While large conceptual differences distinguish experimental approaches, the overview of the functional neuroimaging findings suggests relatively stable neural correlates of episodic odor memory.

  9. Irradiation of odor pollutant using powerful electron beam energy before discharge to the environment

    International Nuclear Information System (INIS)

    Mohd Nahar Othman; Muhd Noor Muhd Yunus; Khairul Zaman Mohd Dahlan; Norasalwa Zakaria; Ku Halim Ku Hamid

    2008-08-01

    The odour or odor complaints received by the Department of Environment of Malaysia in 2006 are about 1082 cases. The trend shows that odor problems have become more and more acute every year. The sources of odor complaints come from many types of industries such as animal raring industry, chemical industries, rubber processing industries, municipal solid wastes (MSW), sewage treatment plants, palm oil industries, petroleum industries and etc. The types of odor control technology used to solve the odor problem still cannot comply to the standard needed by the people. Some of the problems became more problematic because the sources are located in places which are populated. At the same time, there is no regulation concerning the specific odor parameter stated in the Environment Quality Acts 1974. Just recently the Department of Environment drafted a regulation in order to monitor this problem, relating to the nuisance coming from these industries. The aim of this paper is to introduce a new technique of treatment of odor pollutant by using Dimethyl Sulfide (DMS) as sample gas from MSW. The odor gases from Municipal solid waste is irradiated using electron beam irradiation that has been successfully carried out by the Malaysian Nuclear Agency and the result shows that this technique has good potential. (Author)

  10. Magnetic separation in microfluidic systems

    DEFF Research Database (Denmark)

    Smistrup, Kristian

    2007-01-01

    to facilitate real-time monitoring of the experiments. The set-up and experimental protocol are described in detail. Results are presented for ’active’ magnetic bead separators, where on-chip microfabricated electromagnets supply the magnetic field and field gradients necessary for magnetic bead separation....... It is shown conceptually how such a system can be applied for parallel biochemical processing in a microfluidic system. ’Passive’ magnetic separators are presented, where on-chip soft magnetic elements are magnetized by an external magnetic field and create strong magnetic fields and gradients inside...

  11. Seeing odors in color: Cross-modal associations in children and adults from two cultural environments.

    Science.gov (United States)

    Goubet, Nathalie; Durand, Karine; Schaal, Benoist; McCall, Daniel D

    2018-02-01

    We investigated the occurrence and underlying processes of odor-color associations in French and American 6- to 10-year-old children (n = 386) and adults (n = 137). Nine odorants were chosen according to their familiarity to either cultural group. Participants matched each odor with a color, gave hedonic and familiarity judgments, and identified each odor. By 6 years of age, children displayed culture-specific odor-color associations, but age differences were noted in the type of associations. Children and adults in both cultural groups shared common associations and formed associations that were unique to their environment, underscoring the importance of exposure learning in odor-color associations. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Critical components of odors in evaluating the performance of food waste composting plants

    International Nuclear Information System (INIS)

    Mao, I-F.; Tsai, C.-J.; Shen, S.-H.; Lin, T.-F.; Chen, W.-K.; Chen, M.-L.

    2006-01-01

    The current Taiwan government policy toward food waste management encourages composting for resource recovery. This study used olfactometry, gas chromatography-mass spectrometry (GC-MS) and gas detector tubes to evaluate the ambient air at three of the largest food waste composting plants in Taiwan. Ambient air inside the plants, at exhaust outlets and plant boundaries was examined to determine the comprehensive odor performance, critical components, and odor elimination efficiencies of various odor control engineering. Analytical results identified 29 compounds, including ammonia, amines, acetic acid, and multiple volatile organic compounds (VOCs) (hydrocarbons, ketones, esters, terpenes and S-compounds) in the odor from food waste composting plants. Concentrations of six components - ammonia, amines, dimethyl sulfide, acetic acid, ethyl benzene and p-Cymene - exceeded human olfactory thresholds. Ammonia, amines, dimethyl sulfide and acetic acid accounted for most odors compared to numerous VOCs. The results also show that the biotrickling filter was better at eliminating the concentrations of odor, NH 3 , amines, S-compounds and VOCs than the chemical scrubber and biofilters. All levels measured by olfactometry at the boundaries of food waste composting plants (range, 74-115 Odor Concentration (OC)) exceeded Taiwan's EPA standard of 50 OC. This study indicated that the malodor problem continued to be a significant problem for food waste recovery

  13. Critical components of odors in evaluating the performance of food waste composting plants

    Energy Technology Data Exchange (ETDEWEB)

    Mao, I-F. [Institute of Environmental Health Sciences, National Yang-Ming University, No. 155, Sec.2, Li-Nong St., Beitou, Taipei, Taiwan (China)]. E-mail: ifmao@ym.edu.tw; Tsai, C.-J. [Institute of Environmental Health Sciences, National Yang-Ming University, No. 155, Sec.2, Li-Nong St., Beitou, Taipei, Taiwan (China); Shen, S.-H. [Department of Environment Management, Jin Wen Institute of Technology, No. 99, An-Chung Rd., Hsin-Tien City, Taipei, Taiwan (China); Lin, T.-F. [Institute of Environmental Engineering, National Cheng Kung University, No. 1, Ta-Hsueh Rd., Tainan, Taiwan (China); Chen, W.-K. [Department of Environment Management, Jin Wen Institute of Technology, No. 99, An-Chung Rd., Hsin-Tien City, Taipei, Taiwan (China); Chen, M.-L. [Institute of Environmental Health Sciences, National Yang-Ming University, No. 155, Sec.2, Li-Nong St., Beitou, Taipei, Taiwan (China)]. E-mail: mlchen@ym.edu.tw

    2006-11-01

    The current Taiwan government policy toward food waste management encourages composting for resource recovery. This study used olfactometry, gas chromatography-mass spectrometry (GC-MS) and gas detector tubes to evaluate the ambient air at three of the largest food waste composting plants in Taiwan. Ambient air inside the plants, at exhaust outlets and plant boundaries was examined to determine the comprehensive odor performance, critical components, and odor elimination efficiencies of various odor control engineering. Analytical results identified 29 compounds, including ammonia, amines, acetic acid, and multiple volatile organic compounds (VOCs) (hydrocarbons, ketones, esters, terpenes and S-compounds) in the odor from food waste composting plants. Concentrations of six components - ammonia, amines, dimethyl sulfide, acetic acid, ethyl benzene and p-Cymene - exceeded human olfactory thresholds. Ammonia, amines, dimethyl sulfide and acetic acid accounted for most odors compared to numerous VOCs. The results also show that the biotrickling filter was better at eliminating the concentrations of odor, NH{sub 3}, amines, S-compounds and VOCs than the chemical scrubber and biofilters. All levels measured by olfactometry at the boundaries of food waste composting plants (range, 74-115 Odor Concentration (OC)) exceeded Taiwan's EPA standard of 50 OC. This study indicated that the malodor problem continued to be a significant problem for food waste recovery.

  14. From Nose to Memory: The Involuntary Nature of Odor-evoked Autobiographical Memories in Alzheimer's Disease.

    Science.gov (United States)

    El Haj, Mohamad; Gandolphe, Marie Charlotte; Gallouj, Karim; Kapogiannis, Dimitrios; Antoine, Pascal

    2017-12-25

    Research suggests that odors may serve as a potent cue for autobiographical retrieval. We tested this hypothesis in Alzheimer's disease (AD) and investigated whether odor-evoked autobiographical memory is an involuntary process that shares similarities with music-evoked autobiographical memory. Participants with mild AD and controls were asked to retrieve 2 personal memories after odor exposure, after music exposure, and in an odor-and music-free condition. AD participants showed better specificity, emotional experience, mental time travel, and retrieval time after odor and music exposure than in the control condition. Similar beneficial effects of odor and music exposure were observed for autobiographical characteristics (i.e., specificity, emotional experience, and mental time travel), except for retrieval time which was more improved after odor than after music exposure. Interestingly, regression analyses suggested executive involvement in memories evoked in the control condition but not in those evoked after music or odor exposure. These findings suggest the involuntary nature of odor-evoked autobiographical memory in AD. They also suggest that olfactory cuing could serve as a useful and ecologically valid tool to stimulate autobiographical memory, at least in the mild stage of the disease. © The Author(s) 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Combining Ordinary Kriging with wind directions to identify sources of industrial odors in Portland, Oregon.

    Science.gov (United States)

    Eckmann, Ted C; Wright, Samantha G; Simpson, Logan K; Walker, Joe L; Kolmes, Steven A; Houck, James E; Velasquez, Sandra C

    2018-01-01

    This study combines Ordinary Kriging, odor monitoring, and wind direction data to demonstrate how these elements can be applied to identify the source of an industrial odor. The specific case study used as an example of how to address this issue was the University Park neighborhood of Portland, Oregon (USA) where residents frequently complain about industrial odors, and suspect the main source to be a nearby Daimler Trucks North America LLC manufacturing plant. We collected 19,665 odor observations plus 105,120 wind measurements, using an automated weather station to measure winds in the area at five-minute intervals, logging continuously from December 2014 through November 2015, while we also measured odors at 19 locations, three times per day, using methods from the American Society of the International Association for Testing and Materials. Our results quantify how winds vary with season and time of day when industrial odors were observed versus when they were not observed, while also mapping spatiotemporal patterns in these odors using Ordinary Kriging. Our analyses show that industrial odors were detected most frequently to the northwest of the Daimler plant, mostly when winds blew from the southeast, suggesting Daimler's facility is a likely source for much of this odor.

  16. After oxidation, zinc nanoparticles lose their ability to enhance responses to odorants.

    Science.gov (United States)

    Hagerty, Samantha; Daniels, Yasmine; Singletary, Melissa; Pustovyy, Oleg; Globa, Ludmila; MacCrehan, William A; Muramoto, Shin; Stan, Gheorghe; Lau, June W; Morrison, Edward E; Sorokulova, Iryna; Vodyanoy, Vitaly

    2016-12-01

    Electrical responses of olfactory sensory neurons to odorants were examined in the presence of zinc nanoparticles of various sizes and degrees of oxidation. The zinc nanoparticles were prepared by the underwater electrical discharge method and analyzed by atomic force microscopy and X-ray photoelectron spectroscopy. Small (1.2 ± 0.3 nm) zinc nanoparticles significantly enhanced electrical responses of olfactory neurons to odorants. After oxidation, however, these small zinc nanoparticles were no longer capable of enhancing olfactory responses. Larger zinc oxide nanoparticles (15 nm and 70 nm) also did not modulate responses to odorants. Neither zinc nor zinc oxide nanoparticles produced olfactory responses when added without odorants. The enhancement of odorant responses by small zinc nanoparticles was explained by the creation of olfactory receptor dimers initiated by small zinc nanoparticles. The results of this work will clarify the mechanisms for the initial events in olfaction, as well as to provide new ways to alleviate anosmia related to the loss of olfactory receptors.

  17. Evaluation of γ-radiation on oolong tea odor volatiles

    International Nuclear Information System (INIS)

    Fanaro, G.B.; Duarte, R.C.; Santillo, A.G.; Pinto e Silva, M.E.M.; Purgatto, E.

    2012-01-01

    The aim of this study was to evaluate the gamma radiation effects on odor volatiles in oolong tea at doses of 0, 5, 10, 15 and 20 kGy. The volatile organic compounds were extracted by hydrodistillation and analyzed by GC/MS. The irradiation has a large influence on oolong tea odor profile, once it was identified 40% of new compounds after this process, the 5 kGy and 20 kGy were the doses that degraded more volatiles found naturally in this kind of tea and the dose of 10 kGy was the dose that formed more new compounds. Statistical difference was found between the 5 kGy and 15 kGy volatile profiles, however the sensorial analysis showed that the irradiation at dose up 20 kGy did not interfere on consumer perception. - Highlights: ► Forty percent of compounds identified with odor were formed after irradiation. ► Dose of 5 kGy and 20 kGy were the radiation dose that degraded more odors compounds. ► Gamma radiation showed has a direct influence on volatile compounds in oolong tea.

  18. The spatial and temporal patterns of odors sampled by lobsters and crabs in a turbulent plume.

    Science.gov (United States)

    Reidenbach, Matthew A; Koehl, M A R

    2011-09-15

    Odors are dispersed across aquatic habitats by turbulent water flow as filamentous, intermittent plumes. Many crustaceans sniff (take discrete samples of ambient water and the odors it carries) by flicking their olfactory antennules. We used planar laser-induced fluorescence to investigate how flicking antennules of different morphologies (long antennules of spiny lobsters, Panulirus argus; short antennules of blue crabs, Callinectes sapidus) sample fluctuating odor signals at different positions in a turbulent odor plume in a flume to determine whether the patterns of concentrations captured can provide information about an animal's position relative to the odor source. Lobster antennules intercept odors during a greater percentage of flicks and encounter higher peak concentrations than do crab antennules, but because crabs flick at higher frequency, the duration of odor-free gaps between encountered odor pulses is similar. For flicking antennules there were longer time gaps between odor encounters as the downstream distance to the odor source decreases, but shorter gaps along the plume centerline than near the edge. In contrast to the case for antennule flicking, almost all odor-free gaps were <500 ms at all positions in the plume if concentration was measured continuously at the same height as the antennules. Variance in concentration is lower and mean concentration is greater near the substratum, where leg chemosensors continuously sample the plume, than in the water where antennules sniff. Concentrations sampled by legs increase as an animal nears an odor source, but decrease for antennules. Both legs and antennules encounter higher concentrations near the centerline than at the edge of the plume.

  19. The impact of odor-reward memory on chemotaxis in larval Drosophila.

    Science.gov (United States)

    Schleyer, Michael; Reid, Samuel F; Pamir, Evren; Saumweber, Timo; Paisios, Emmanouil; Davies, Alexander; Gerber, Bertram; Louis, Matthieu

    2015-05-01

    How do animals adaptively integrate innate with learned behavioral tendencies? We tackle this question using chemotaxis as a paradigm. Chemotaxis in the Drosophila larva largely results from a sequence of runs and oriented turns. Thus, the larvae minimally need to determine (i) how fast to run, (ii) when to initiate a turn, and (iii) where to direct a turn. We first report how odor-source intensities modulate these decisions to bring about higher levels of chemotactic performance for higher odor-source intensities during innate chemotaxis. We then examine whether the same modulations are responsible for alterations of chemotactic performance by learned odor "valence" (understood throughout as level of attractiveness). We find that run speed (i) is neither modulated by the innate nor by the learned valence of an odor. Turn rate (ii), however, is modulated by both: the higher the innate or learned valence of the odor, the less often larvae turn whenever heading toward the odor source, and the more often they turn when heading away. Likewise, turning direction (iii) is modulated concordantly by innate and learned valence: turning is biased more strongly toward the odor source when either innate or learned valence is high. Using numerical simulations, we show that a modulation of both turn rate and of turning direction is sufficient to account for the empirically found differences in preference scores across experimental conditions. Our results suggest that innate and learned valence organize adaptive olfactory search behavior by their summed effects on turn rate and turning direction, but not on run speed. This work should aid studies into the neural mechanisms by which memory impacts specific aspects of behavior. © 2015 Schleyer et al.; Published by Cold Spring Harbor Laboratory Press.

  20. Testing odorant-receptor interaction theories in humans through discrimination of isotopomers

    Directory of Open Access Journals (Sweden)

    Mara Andrione

    2017-12-01

    Full Text Available Odour reception takes place on the olfactory receptor neuron membrane, where molecular receptors interact with volatile odorant molecules. This interaction is classically thought to rely on chemical and structural features of the odorant, e.g. size, shape, functional groups. However, this model does not allow formulating a correct prediction for the smell of an odorant, suggesting that other molecular properties may play a role in the odour transduction process. An alternative model of olfaction maintains that odorant receptors can probe not only the structural and chemical features, but also the molecular vibration spectrum of the odorants. This constitutes the so-called vibration model of olfaction. According to this model, two isotopomers of the same molecule, i.e. two forms of the same molecule, one unaltered and one in which one or more hydrogen atoms are substituted with deuterium – which are therefore structurally and chemically identical, but with different molecular vibration spectra – would interact differently with an olfactory receptor, producing different olfactory perceptions in the brain. Here, we report on a duo-trio discrimination experiment conducted on human subjects, testing isotopomer pairs that have recently been shown to be differentially encoded in the honeybee brain.

  1. The "Sniffin' Kids" test--a 14-item odor identification test for children.

    Directory of Open Access Journals (Sweden)

    Valentin A Schriever

    Full Text Available Tools for measuring olfactory function in adults have been well established. Although studies have shown that olfactory impairment in children may occur as a consequence of a number of diseases or head trauma, until today no consensus on how to evaluate the sense of smell in children exists in Europe. Aim of the study was to develop a modified "Sniffin' Sticks" odor identification test, the "Sniffin' Kids" test for the use in children. In this study 537 children between 6-17 years of age were included. Fourteen odors, which were identified at a high rate by children, were selected from the "Sniffin' Sticks" 16-item odor identification test. Normative date for the 14-item "Sniffin' Kids" odor identification test was obtained. The test was validated by including a group of congenital anosmic children. Results show that the "Sniffin' Kids" test is able to discriminate between normosmia and anosmia with a cutoff value of >7 points on the odor identification test. In addition the test-retest reliability was investigated in a group of 31 healthy children and shown to be ρ = 0.44. With the 14-item odor identification "Sniffin' Kids" test we present a valid and reliable test for measuring olfactory function in children between ages 6-17 years.

  2. Cross-cultural color-odor associations

    NARCIS (Netherlands)

    Levitan, C.A.; Ren, J.; Boesveldt, S.; Chan, J.; McKenzie, K.J.; Levin, J.A.; Leong, C.X.; Bosch, van den J.F.

    2014-01-01

    Colors and odors are associated; for instance, people typically match the smell of strawberries to the color pink or red. These associations are forms of crossmodal correspondences. Recently, there has been discussion about the extent to which these correspondences arise for structural reasons

  3. Reef odor: a wake up call for navigation in reef fish larvae.

    Directory of Open Access Journals (Sweden)

    Claire B Paris

    Full Text Available The behavior of reef fish larvae, equipped with a complex toolbox of sensory apparatus, has become a central issue in understanding their transport in the ocean. In this study pelagic reef fish larvae were monitored using an unmanned open-ocean tracking device, the drifting in-situ chamber (DISC, deployed sequentially in oceanic waters and in reef-born odor plumes propagating offshore with the ebb flow. A total of 83 larvae of two taxonomic groups of the families Pomacentridae and Apogonidae were observed in the two water masses around One Tree Island, southern Great Barrier Reef. The study provides the first in-situ evidence that pelagic reef fish larvae discriminate reef odor and respond by changing their swimming speed and direction. It concludes that reef fish larvae smell the presence of coral reefs from several kilometers offshore and this odor is a primary component of their navigational system and activates other directional sensory cues. The two families expressed differences in their response that could be adapted to maintain a position close to the reef. In particular, damselfish larvae embedded in the odor plume detected the location of the reef crest and swam westward and parallel to shore on both sides of the island. This study underlines the critical importance of in situ Lagrangian observations to provide unique information on larval fish behavioral decisions. From an ecological perspective the central role of olfactory signals in marine population connectivity raises concerns about the effects of pollution and acidification of oceans, which can alter chemical cues and olfactory responses.

  4. Odor-active constituents in fresh pineapple (Ananas comosus [L.] Merr.) by quantitative and sensory evaluation.

    Science.gov (United States)

    Tokitomo, Yukiko; Steinhaus, Martin; Büttner, Andrea; Schieberle, Peter

    2005-07-01

    By application of aroma extract dilution analysis (AEDA) to an aroma distillate prepared from fresh pineapple using solvent-assisted flavor evaporation (SAFE), 29 odor-active compounds were detected in the flavor dilution (FD) factor range of 2 to 4,096. Quantitative measurements performed by stable isotope dilution assays (SIDA) and a calculation of odor activity values (OAVs) of 12 selected odorants revealed the following compounds as key odorants in fresh pineapple flavor: 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDF; sweet, pineapple-like, caramel-like), ethyl 2-methylpropanoate (fruity), ethyl 2-methylbutanoate (fruity) followed by methyl 2-methylbutanoate (fruity, apple-like) and 1-(E,Z)-3,5-undecatriene (fresh, pineapple-like). A mixture of these 12 odorants in concentrations equal to those in the fresh pineapple resulted in an odor profile similar to that of the fresh juice. Furthermore, the results of omission tests using the model mixture showed that HDF and ethyl 2-methylbutanoate are character impact odorants in fresh pineapple.

  5. Lemon Odor Reduces Stress-induced Neuronal Activation in the Emotion Expression System: An Animal Model Study

    Science.gov (United States)

    Sanada, Kazue; Sugimoto, Koji; Shutoh, Fumihiro; Hisano, Setsuji

    Perception of particular sensory stimuli from the surroundings can influence emotion in individuals. In an uncomfortable situation, humans protect themselves from some aversive stimulus by acutely evoking a stress response. Animal model studies have contributed to an understanding of neuronal mechanisms underlying the stress response in humans. To study a possible anti-stressful effect of lemon odor, an excitation of neurons secreting corticotropin-releasing hormone (CRH) as a primary factor of the hypothalamic-pituitary-adrenal axis (HPA) was analyzed in animal model experiments, in which rats are restrained in the presence or absence of the odor. The effect was evaluated by measuring expression of c-Fos (an excited neuron marker) in the hypothalamic paraventricular nucleus (PVN), a key structure of the HPA in the brain. We prepared 3 animal groups: Groups S, L and I. Groups S and L were restrained for 30 minutes while being blown by air and being exposed to the lemon odor, respectively. Group I was intact without any treatment. Two hours later of the onset of experiments, brains of all groups were sampled and processed for microscopic examination. Brain sections were processed for c-Fos immunostaining and/or in situ hybridization for CRH. In Group S but not in Group I, c-Fos expression was found in the PVN. A combined in situ hybridization-immunohistochemical dual labeling revealed that CRH mRNA-expressing neurons express c-Fos. In computer-assisted automatic counting, the incidence of c-Fos-expressing neurons in the entire PVN was statistically lower in Group L than in Group S. Detailed analysis of PVN subregions demonstrated that c-Fos-expressing neurons are fewer in Group L than in Group S in the dorsal part of the medial parvocellular subregion. These results may suggest that lemon odor attenuates the restraint stress-induced neuronal activation including CRH neurons, presumably mimicking an aspect of stress responses in humans.

  6. The mere exposure effect depends on an odor?s initial pleasantness

    OpenAIRE

    Delplanque, Sylvain; Coppin, G?raldine; Bloesch, Laur?ne; Cayeux, Isabelle; Sander, David

    2015-01-01

    The mere exposure phenomenon refers to improvement of one’s attitude toward an a priori neutral stimulus after its repeated exposure. The extent to which such a phenomenon influences evaluation of a priori emotional stimuli remains under-investigated. Here we investigated this question by presenting participants with different odors varying in a priori pleasantness during different sessions spaced over time. Participants were requested to report each odor’s pleasantness, intensity, and famili...

  7. Effects of odor generated from the glycine/glucose Maillard reaction on human mood and brainwaves.

    Science.gov (United States)

    Zhou, Lanxi; Ohata, Motoko; Arihara, Keizo

    2016-06-15

    Effects of the odor generated from the glycine/glucose Maillard reaction on human mood and brainwaves were investigated in the present study. Equimolar solutions of glucose and glycine were adjusted to pH 7 and pH 9 and heated at 90 °C for 30 min. The odor generated from the glycine/glucose Maillard reaction significantly decreased negative moods. Its effects on brainwaves differed according to pH; alpha brainwave distribution was increased after inhalation of the odor generated at pH 7, whereas it was decreased by the odor generated at pH 9. The effects on mood and brainwaves were also measured after inhalation of model solutions, which comprised of potent odorants determined by aroma extract dilution analysis (AEDA), and the results were similar to those obtained with the Maillard reaction samples. Therefore, odors constructed by potent odorants could influence human mood and brainwaves. Among all potent odorants, 2,3-dimethylpyrazine and 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) were identified as the strongest, and high pH values resulted in higher yields of these odorants. Furthermore, DMHF was identified as the putative agent responsible for the decrease in alpha brainwave distribution after smelling the pH-9 Maillard reaction sample since higher concentrations of DMHF resulted in a similar effect.

  8. Both odor identification and ApoE-ε4 contribute to normative cognitive aging.

    Science.gov (United States)

    Finkel, Deborah; Reynolds, Chandra A; Larsson, Maria; Gatz, Margaret; Pedersen, Nancy L

    2011-12-01

    Research indicates that apoliprotein E (ApoE) plays a role in the development of Alzheimer's disease (AD) and possibly in the cognitive decline associated with normative aging. More recently, researchers have shown that ApoE is expressed in olfactory brain structures, and a relationship among ApoE, AD, and olfactory function has been proposed. In the current analyses, we investigated the contribution of ApoE and odor identification in decline trajectories associated with normative cognitive aging in various domains, using longitudinal data on cognitive performance available from the Swedish Adoption/Twin Study of Aging. Data on both ApoE status and olfactory functioning were available from 455 individuals ranging in age from 50 to 88 years at the first measurement occasion. Odor identification was measured via a mailed survey. Cognitive performance was assessed in up to 5 waves of in-person testing covering a period of 16 years. Latent growth curve analyses incorporating odor identification and ApoE status indicated a main effect of odor identification on the performance level in three cognitive domains: verbal, memory, and speed. A main effect of ApoE on rates of decline after age 65 was found for verbal, spatial, and speed factors. The consistency of results across cognitive domains provides support for theories that posit central nervous system-wide origins of the olfaction-cognition-ApoE relationship; however, olfactory errors and APOE ε4 show unique and differential effects on cognitive trajectory features.

  9. Habenula and interpeduncular nucleus differentially modulate predator odor-induced innate fear behavior in rats.

    Science.gov (United States)

    Vincenz, Daniel; Wernecke, Kerstin E A; Fendt, Markus; Goldschmidt, Jürgen

    2017-08-14

    Fear is an important behavioral system helping humans and animals to survive potentially dangerous situations. Fear can be innate or learned. Whereas the neural circuits underlying learned fear are already well investigated, the knowledge about the circuits mediating innate fear is still limited. We here used a novel, unbiased approach to image in vivo the spatial patterns of neural activity in odor-induced innate fear behavior in rats. We intravenously injected awake unrestrained rats with a 99m-technetium labeled blood flow tracer (99mTc-HMPAO) during ongoing exposure to fox urine or water as control, and mapped the brain distribution of the trapped tracer using single-photon emission computed tomography (SPECT). Upon fox urine exposure blood flow increased in a number of brain regions previously associated with odor-induced innate fear such as the amygdala, ventromedial hypothalamus and dorsolateral periaqueductal grey, but, unexpectedly, decreased at higher significance levels in the interpeduncular nucleus (IPN). Significant flow changes were found in regions monosynaptically connected to the IPN. Flow decreased in the dorsal tegmentum and entorhinal cortex. Flow increased in the habenula (Hb) and correlated with odor effects on behavioral defensive strategy. Hb lesions reduced avoidance of but increased approach to the fox urine while IPN lesions only reduced avoidance behavior without approach behavior. Our study identifies a new component, the IPN, of the neural circuit mediating odor-induced innate fear behavior in mammals and suggests that the evolutionarily conserved Hb-IPN system, which has recently been implicated in cued fear, also forms an integral part of the innate fear circuitry. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  10. The Intensity of Human Body Odors and the MHC: Should We Expect a Link?

    Directory of Open Access Journals (Sweden)

    Claus Wedekind

    2006-01-01

    Full Text Available It is now well established that genes within the major histocompatibility complex (MHC somehow affect the production of body odors in several vertebrates, including humans. Here we discuss whether variation in the intensity of body odors may be influenced by the MHC. In order to examine this question, we have to control for MHC-linked odor perception on the smeller's side. Such a control is necessary because the perception of pleasantness and intensity seem to be confounded, and the causalities are still unsolved. It has previously been found that intense odors are scored as less pleasant if the signaler and the receiver are of MHC-dissimilar type, but not if they are of MHC similar type. We argue, and first data suggest, that an effect of the degree of MHC-heterozygosity and odor intensity is likely (MHC-homozygotes may normally smell more intense, while there is currently no strong argument for other possible links between the MHC and body odor intensity.

  11. Characterization of Odorant Compounds from Mechanical Aerated Pile Composting and Static Aerated Pile Composting.

    Science.gov (United States)

    Kumari, Priyanka; Lee, Joonhee; Choi, Hong-Lim

    2016-04-01

    We studied airborne contaminants (airborne particulates and odorous compounds) emitted from compost facilities in South Korea. There are primarily two different types of composting systems operating in Korean farms, namely mechanical aerated pile composting (MAPC) and aerated static pile composting (SAPC). In this study, we analyzed various particulate matters (PM10, PM7, PM2.5, PM1, and total suspended particles), volatile organic compounds and ammonia, and correlated these airborne contaminants with microclimatic parameters, i.e., temperature and relative humidity. Most of the analyzed airborne particulates (PM7, PM2.5, and PM1) were detected in high concentration at SAPC facilities compered to MAPC; however these differences were statistically non-significant. Similarly, most of the odorants did not vary significantly between MAPC and SAPC facilities, except for dimethyl sulfide (DMS) and skatole. DMS concentrations were significantly higher in MAPC facilities, whereas skatole concentrations were significantly higher in SAPC facilities. The microclimate variables also did not vary significantly between MAPC and SAPC facilities, and did not correlate significantly with most of the airborne particles and odorous compounds, suggesting that microclimate variables did not influence their emission from compost facilities. These findings provide insight into the airborne contaminants that are emitted from compost facilities and the two different types of composting agitation systems.

  12. Major Odorants Released as Urinary Volatiles by Urinary Incontinent Patients

    Directory of Open Access Journals (Sweden)

    In Young Sa

    2013-07-01

    Full Text Available In this study, volatile urinary components were collected using three different types of samples from patients suffering from urinary incontinence (UI: (1 urine (A; (2 urine + non-used pad (B; and (3 urine + used pad (C. In addition, urine + non-used pad (D samples from non-patients were also collected as a reference. The collection of urinary volatiles was conducted with the aid of a glass impinger-based mini-chamber method. Each of the four sample types (A through D was placed in a glass impinger and incubated for 4 hours at 37 °C. Ultra pure air was then passed through the chamber, and volatile urine gas components were collected into Tedlar bags at the other end. These bag samples were then analyzed for a wide range of VOCs and major offensive odorants (e.g., reduced sulfur compounds (RSCs, carbonyls, trimethylamine (TMA, ammonia, etc.. Among the various odorants, sulfur compounds (methanethiol and hydrogen sulfide and aldehydes (acetaldehyde, butylaldehyde, and isovaleraldehyde were detected above odor threshold and predicted to contribute most effectively to odor intensity of urine incontinence.

  13. The participation of cortical amygdala in innate, odor-driven behavior

    Science.gov (United States)

    Root, Cory M.; Denny, Christine A.; Hen, René; Axel, Richard

    2014-01-01

    Innate behaviors are observed in naïve animals without prior learning or experience, suggesting that the neural circuits that mediate these behaviors are genetically determined and stereotyped. The neural circuits that convey olfactory information from the sense organ to the cortical and subcortical olfactory centers have been anatomically defined1-3 but the specific pathways responsible for innate responses to volatile odors have not been identified. We have devised genetic strategies that demonstrate that a stereotyped neural circuit that transmits information from the olfactory bulb to cortical amygdala is necessary for innate aversive and appetitive behaviors. Moreover, we have employed the promoter of the activity-dependent gene, arc, to express the photosensitive ion channel, channelrhodopsin, in neurons of the cortical amygdala activated by odors that elicit innate behaviors. Optical activation of these neurons leads to appropriate behaviors that recapitulate the responses to innate odors. These data indicate that the cortical amygdala plays a critical role in the generation of innate odor-driven behaviors but do not preclude the participation of cortical amygdala in learned olfactory behaviors. PMID:25383519

  14. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium.

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2012-02-01

    BACKGROUND: Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. RESULTS: Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. CONCLUSION: Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  15. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2011-08-22

    Abstract Background Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. Results Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. Conclusion Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  16. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium

    Directory of Open Access Journals (Sweden)

    Hatt Hanns

    2011-08-01

    Full Text Available Abstract Background Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. Results Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. Conclusion Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  17. Odor-Active Compounds in the Special Flavor Hops Huell Melon and Polaris.

    Science.gov (United States)

    Neiens, Silva D; Steinhaus, Martin

    2018-02-14

    The volatiles isolated from samples of the special flavor hop varieties, Huell Melon and Polaris, and from the aroma hop variety, Hallertau Tradition, by solvent extraction and solvent-assisted flavor evaporation (SAFE) were subjected to a comparative aroma extract dilution analysis (cAEDA), which resulted in 46 odor-active compounds in the flavor dilution (FD) factor range of 16 to 2048. On the basis of high FD factors, myrcene, (3R)-linalool, and 2- and 3-methylbutanoic acid were confirmed as important variety-independent hop odorants. (1R,4S)-Calamenene was identified for the first time as an odor-active compound in hops. Clear differences in the FD factors and their subsequent objectification by stable isotope dilution quantitation suggested that high concentrations of the esters ethyl 2-methylbutanoate, ethyl 2-methylpropanoate, and propyl 2-methylbutanoate cause the characteristic fruity, cantaloupe-like odor note in Huell Melon hops, whereas the fruity and minty odor notes in Polaris are associated with high amounts of 3-methylbutyl acetate and 1,8-cineole.

  18. Earwigs ( Labidura riparia) mimic rotting-flesh odor to deceive vertebrate predators

    Science.gov (United States)

    Byers, John A.

    2015-08-01

    Many insects repel predators with caustic chemicals, while insects mimicking odors of wastes/dead insects to fool predators have not been documented. We found that the shore earwig, Labidura riparia (Dermaptera: Labiduridae) when bitten by anole lizards, Anolis carolinenesus, spits a rotting-flesh odor that deceives these insectivores into rejecting prey. Once a lizard attacked and rejected an earwig, the lizard did not attack another earwig during several weeks despite consuming other prey, indicating associative learning after one trial. The fetid odor was found in the head-prothorax containing salivary glands of both male and female earwigs and was comprised of ˜100 ng dimethyl disulfide and ˜600 ng dimethyl trisulfide. Nymphs had odorous sulfides after prolonged attacks by harvester ants, Pogonomyrmex rugosus, who were only deterred by the earwig's forceps. Sulfides released by the earwig are similar to odors of carrion/feces, which may be innately repulsive to some vertebrate predators. The mean initial discharge percentage (IDP) of sulfides from a cohort of earwigs was 62 %; however, IDPs of individuals were highly variable (3-99 %; mean 57 %). The discharge refill time (DRT) to refill 50 % of the earwig's allomone reservoir was estimated at 13 h. A positive relationship in sulfide amounts with body weight was found only in females in 2009, suggesting metabolic cost tradeoffs were revealed when sulfide content was half that in 2010. This is the first report of insects releasing sulfur-containing compounds that may mimic carrion-fecal odors as a deceptive defense against vertebrate predators.

  19. Body odor quality predicts behavioral attractiveness in humans.

    Science.gov (United States)

    Roberts, S Craig; Kralevich, Alexandra; Ferdenzi, Camille; Saxton, Tamsin K; Jones, Benedict C; DeBruine, Lisa M; Little, Anthony C; Havlicek, Jan

    2011-12-01

    Growing effort is being made to understand how different attractive physical traits co-vary within individuals, partly because this might indicate an underlying index of genetic quality. In humans, attention has focused on potential markers of quality such as facial attractiveness, axillary odor quality, the second-to-fourth digit (2D:4D) ratio and body mass index (BMI). Here we extend this approach to include visually-assessed kinesic cues (nonverbal behavior linked to movement) which are statistically independent of structural physical traits. The utility of such kinesic cues in mate assessment is controversial, particularly during everyday conversational contexts, as they could be unreliable and susceptible to deception. However, we show here that the attractiveness of nonverbal behavior, in 20 male participants, is predicted by perceived quality of their axillary body odor. This finding indicates covariation between two desirable traits in different sensory modalities. Depending on two different rating contexts (either a simple attractiveness rating or a rating for long-term partners by 10 female raters not using hormonal contraception), we also found significant relationships between perceived attractiveness of nonverbal behavior and BMI, and between axillary odor ratings and 2D:4D ratio. Axillary odor pleasantness was the single attribute that consistently predicted attractiveness of nonverbal behavior. Our results demonstrate that nonverbal kinesic cues could reliably reveal mate quality, at least in males, and could corroborate and contribute to mate assessment based on other physical traits.

  20. Distributed systems design using separable communications

    International Nuclear Information System (INIS)

    Capel, A.C.; Yan, G.

    1980-01-01

    One of the promises of distributed systems is the ability to design each process function largely independently of the others, and in many cases locate the resulting hardware in close proximity to the application. The communications architecture for such systems should be approached in the same way, using separable communications facilities to meet individual sets of requirements while at the same time reducing the interactions between functions. Where complete physical separation is not feasible and hardware resource sharing is required, the protocols should be designed emphasizing the logical separation of communication paths. This paper discusses the different types of communications for process control applictions and the parameters which need to be characterized in designing separable communications for distributed systems. (auth)

  1. Odor-context effects in free recall after a short retention interval: a new methodology for controlling adaptation.

    Science.gov (United States)

    Isarida, Takeo; Sakai, Tetsuya; Kubota, Takayuki; Koga, Miho; Katayama, Yu; Isarida, Toshiko K

    2014-04-01

    The present study investigated context effects of incidental odors in free recall after a short retention interval (5 min). With a short retention interval, the results are not confounded by extraneous odors or encounters with the experimental odor and possible rehearsal during a long retention interval. A short study time condition (4 s per item), predicted not to be affected by adaptation to the odor, and a long study time condition (8 s per item) were used. Additionally, we introduced a new method for recovery from adaptation, where a dissimilar odor was briefly presented at the beginning of the retention interval, and we demonstrated the effectiveness of this technique. An incidental learning paradigm was used to prevent overshadowing from confounding the results. In three experiments, undergraduates (N = 200) incidentally studied words presented one-by-one and received a free recall test. Two pairs of odors and a third odor having different semantic-differential characteristics were selected from 14 familiar odors. One of the odors was presented during encoding, and during the test, the same odor (same-context condition) or the other odor within the pair (different-context condition) was presented. Without using a recovery-from-adaptation method, a significant odor-context effect appeared in the 4-s/item condition, but not in the 8-s/item condition. Using the recovery-from-adaptation method, context effects were found for both the 8- and the 4-s/item conditions. The size of the recovered odor-context effect did not change with study time. There were no serial position effects. Implications of the present findings are discussed.

  2. A machine learning approach for the identification of odorant binding proteins from sequence-derived properties

    Directory of Open Access Journals (Sweden)

    Suganthan PN

    2007-09-01

    Full Text Available Abstract Background Odorant binding proteins (OBPs are believed to shuttle odorants from the environment to the underlying odorant receptors, for which they could potentially serve as odorant presenters. Although several sequence based search methods have been exploited for protein family prediction, less effort has been devoted to the prediction of OBPs from sequence data and this area is more challenging due to poor sequence identity between these proteins. Results In this paper, we propose a new algorithm that uses Regularized Least Squares Classifier (RLSC in conjunction with multiple physicochemical properties of amino acids to predict odorant-binding proteins. The algorithm was applied to the dataset derived from Pfam and GenDiS database and we obtained overall prediction accuracy of 97.7% (94.5% and 98.4% for positive and negative classes respectively. Conclusion Our study suggests that RLSC is potentially useful for predicting the odorant binding proteins from sequence-derived properties irrespective of sequence similarity. Our method predicts 92.8% of 56 odorant binding proteins non-homologous to any protein in the swissprot database and 97.1% of the 414 independent dataset proteins, suggesting the usefulness of RLSC method for facilitating the prediction of odorant binding proteins from sequence information.

  3. Location of odor sources and the affected population in Imperial County, California

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, J.L.

    1981-08-01

    This report is divided into four sections. The first two sections contain general background information on Imperial County. The third section is a general discussion of odor sources in Imperial County, and the fourth maps the specific odor sources, the expected areas of perception, and the affected populations. this mapping is done for the Imperial Valley and each of the four Imperial County KGRA's (Known Geothermal Resource Areas) where odor from the development of the geothermal energy may affect population.

  4. Excretion and Perception of a Characteristic Odor in Urine after Asparagus Ingestion: a Psychophysical and Genetic Study

    Science.gov (United States)

    Bykowski, Cathy; Duke, Fujiko F.; Reed, Danielle R.

    2011-01-01

    The urine of people who have recently eaten asparagus has a sulfurous odor, which is distinct and similar to cooked cabbage. Using a 2-alternative forced-choice procedure, we examined individual differences in both the production of the odorants and the perception of this asparagus odor in urine. We conclude that individual differences exist in both odorant production and odor perception. The biological basis for the inability to produce the metabolite in detectable quantities is unknown, but the inability to smell the odor is associated with a single nucleotide polymorphism (rs4481887) within a 50-gene cluster of olfactory receptors. PMID:20876394

  5. New Look at odorization levels for propane gas. [Ethyl mercaptan; thiophane; equilibrium K values

    Energy Technology Data Exchange (ETDEWEB)

    Whisman, M.L.; Goetzinger, J.W.; Cotton, F.O.; Brinkman, D.W.; Thompson, C.J.

    1977-09-01

    Nearly 4,000 persons participated in a study to evaluate three odorant systems in four test modes and at 24 different test sites. Participants included trained panels, untrained ERDA employees, and several thousand untrained volunteer evaluators. The classical testing technique and three modified test modes were used to represent a spectrum of conditions that would define the effect of environmental familiarity and mental distractions upon olfactory responses to LP-gas. Significant efforts were directed toward determination of odorant levels that not only can be detected but also will be detected. The study showed that in addition to defects of the nasal anatomy, psychological factors also affect olfactory responses, and that unfamiliarity with a given environment as well as anxieties or mental distractions can produce reduced awareness to odorants intended to warn individuals of the presence of LP-gas. A second part of the study involved a laboratory determination of equilibrium K-values for both ethyl mercaptan and thiophane at three temperatures. Novel sample handling and gas chromatographic techniques provided reproducible results which were in close agreement with theoretical predictions. (28 tables, 29 tables)

  6. Hedonic appreciation and verbal description of pleasant and unpleasant odors in untrained, trainee cooks, flavorists and perfumers

    Directory of Open Access Journals (Sweden)

    Caroline eSezille

    2014-01-01

    Full Text Available Olfaction is characterized by a salient hedonic dimension. Previous studies have shown that these affective responses to odors are modulated by physicochemical, physiological and cognitive factors. The present study examined expertise influenced processing of pleasant and unpleasant odors on both perceptual and verbal levels. For this, performance on 2 olfactory tasks was compared between novices, trainee cooks and experts (perfumers and flavorists: members of all groups rated the intensity and pleasantness of pleasant and unpleasant odors (perceptual tasks. They were also asked to describe each of the 20 odorants as precisely as possible (verbal description task. On a perceptual level, results revealed that there were no group-related differences in hedonic ratings for unpleasant and pleasant odors. On a verbal level, descriptions of smells were richer (e.g. chemical, olfactory qualities and olfactory sources terms and did not refer to pleasantness in experts compared to untrained subjects who used terms referring to odor sources (e.g. candy accompanied by terms referring to odor hedonics. In conclusion, the present study suggests that as novices, experts are able to perceptually discriminate odors on the basis of their pleasantness. However, on a semantic level, they conceptualize odors differently, being inclined to avoid any reference to odor hedonics.

  7. Predator cat odors activate sexual arousal pathways in brains of Toxoplasma gondii infected rats.

    Directory of Open Access Journals (Sweden)

    Patrick K House

    Full Text Available Cat odors induce rapid, innate and stereotyped defensive behaviors in rats at first exposure, a presumed response to the evolutionary pressures of predation. Bizarrely, rats infected with the brain parasite Toxoplasma gondii approach the cat odors they typically avoid. Since the protozoan Toxoplasma requires the cat to sexually reproduce, this change in host behavior is thought to be a remarkable example of a parasite manipulating a mammalian host for its own benefit. Toxoplasma does not influence host response to non-feline predator odor nor does it alter behavior on olfactory, social, fear or anxiety tests, arguing for specific manipulation in the processing of cat odor. We report that Toxoplasma infection alters neural activity in limbic brain areas necessary for innate defensive behavior in response to cat odor. Moreover, Toxoplasma increases activity in nearby limbic regions of sexual attraction when the rat is exposed to cat urine, compelling evidence that Toxoplasma overwhelms the innate fear response by causing, in its stead, a type of sexual attraction to the normally aversive cat odor.

  8. Predator cat odors activate sexual arousal pathways in brains of Toxoplasma gondii infected rats.

    Science.gov (United States)

    House, Patrick K; Vyas, Ajai; Sapolsky, Robert

    2011-01-01

    Cat odors induce rapid, innate and stereotyped defensive behaviors in rats at first exposure, a presumed response to the evolutionary pressures of predation. Bizarrely, rats infected with the brain parasite Toxoplasma gondii approach the cat odors they typically avoid. Since the protozoan Toxoplasma requires the cat to sexually reproduce, this change in host behavior is thought to be a remarkable example of a parasite manipulating a mammalian host for its own benefit. Toxoplasma does not influence host response to non-feline predator odor nor does it alter behavior on olfactory, social, fear or anxiety tests, arguing for specific manipulation in the processing of cat odor. We report that Toxoplasma infection alters neural activity in limbic brain areas necessary for innate defensive behavior in response to cat odor. Moreover, Toxoplasma increases activity in nearby limbic regions of sexual attraction when the rat is exposed to cat urine, compelling evidence that Toxoplasma overwhelms the innate fear response by causing, in its stead, a type of sexual attraction to the normally aversive cat odor.

  9. High-Throughput Automatic Training System for Odor-Based Learned Behaviors in Head-Fixed Mice

    Directory of Open Access Journals (Sweden)

    Zhe Han

    2018-02-01

    Full Text Available Understanding neuronal mechanisms of learned behaviors requires efficient behavioral assays. We designed a high-throughput automatic training system (HATS for olfactory behaviors in head-fixed mice. The hardware and software were constructed to enable automatic training with minimal human intervention. The integrated system was composed of customized 3D-printing supporting components, an odor-delivery unit with fast response, Arduino based hardware-controlling and data-acquisition unit. Furthermore, the customized software was designed to enable automatic training in all training phases, including lick-teaching, shaping and learning. Using HATS, we trained mice to perform delayed non-match to sample (DNMS, delayed paired association (DPA, Go/No-go (GNG, and GNG reversal tasks. These tasks probed cognitive functions including sensory discrimination, working memory, decision making and cognitive flexibility. Mice reached stable levels of performance within several days in the tasks. HATS enabled an experimenter to train eight mice simultaneously, therefore greatly enhanced the experimental efficiency. Combined with causal perturbation and activity recording techniques, HATS can greatly facilitate our understanding of the neural-circuitry mechanisms underlying learned behaviors.

  10. Mere odor exposure learning in the rat neonate immediately after birth and 1 day later.

    Science.gov (United States)

    Miller, Stacie S; Spear, Norman E

    2010-05-01

    Rat pups are more resistant to retroactive associative interference 3 hr after birth than 24 hr later [Cheslock et al. [2004] Developmental Science, 7, 581-598]. The present experiments tested the effect of age, retention interval and dam presence during the retention interval on odor-induced motor activity subsequent to mere odor exposure. Rats were exposed to an hour of odor immediately after birth or approximately 1 day later and tested after a given retention interval (3 or 27 hr [Exp 1]; 0, 30, 75, or 180 min [Exp. 2]). They spent the retention interval either in the presence or absence of a foster dam (Exp. 1 and 3). After the retention interval, pups were tested in a 4-min activity test including a 2-min baseline period and 2 min of odor exposure. Overall activity was scored during tape-playback. Odor-exposed pups were more active than nonexposed pups during reexposure to the odor during testing, but this was true only for P0 pups. In contrast, P1 pups without prior odor exposure were active during testing and behaviorally quieted in the presence of the odor they were previously exposed to. Though 1 day apart, newborn rats just hours old lack many of the experiences that a 1-day-old has had including nursing, huddling, and being groomed. These experiences are associated with, among other stimuli, a barrage of olfactory cues (e.g., colostrum, saliva, dander, feces, and urine). P0 and P1 pups also differ in their proximity from the birthing experience and associated neurochemical changes. The age-related pattern of responding to odors based on previous odor exposure was discussed in relation to these and other possibilities.

  11. Mere odor exposure learning in the rat neonate immediately after birth and one day later

    Science.gov (United States)

    Miller, Stacie S.; Spear, Norman E.

    2011-01-01

    Rat pups are more resistant to retroactive associative interference 3 hrs after birth than 24 hours later (Cheslock, Sanders, & Spear, 2004). The present experiments tested the effect of age, retention interval and dam presence during the retention interval on odor-induced motor activity subsequent to mere odor exposure. Rats were exposed to an hour of odor immediately after birth or approximately one day later and tested after a given retention interval (3 hrs or 27 hrs [Exp 1]; 0, 30, 75, or 180 min [Exp. 2]). They spent the retention interval either in the presence or absence of a foster dam (Exp. 1 and 3). After the retention interval, pups were tested in a four-minute activity test including a two-minute baseline period and two minutes of odor exposure. Overall activity was scored during tape-playback. Odor-exposed pups were more active than non-exposed pups during reexposure to the odor during testing, but this was true only for P0 pups. In contrast, P1 pups without prior odor exposure were active during testing and behaviorally quieted in the presence of the odor they were previously exposed to. Though one day apart, newborn rats just hours old lack many of the experiences that a one day old has had including nursing, huddling, and being groomed. These experiences are associated with, among other stimuli, a barrage of olfactory cues (e.g., colostrum, saliva, dander, feces, and urine). P0 and P1 pups also differ in their proximity from the birthing experience and associated neurochemical changes. The age-related pattern of responding to odors based on previous odor exposure was discussed in relation to these and other possibilities. PMID:20411590

  12. Predator odor avoidance as a rodent model of anxiety: learning-mediated consequences beyond the initial exposure.

    Science.gov (United States)

    Staples, Lauren G

    2010-11-01

    Prey animals such as rats display innate defensive responses when exposed to the odor of a predator, providing a valuable means of studying the neurobiology of anxiety. While the unconditioned behavioral and neural responses to a single predator odor exposure have been well documented, the paradigm can also be used to study learning-dependent adaptations that occur following repeated exposure to a stressor or associated stimuli. In developing preclinical models for human anxiety disorders this is advantageous, as anxiety disorders seldom involve a single acute experience of anxiety, but rather are chronic and/or recurring illnesses. Part 1 of this review summarizes current research on the three most commonly used predator-related odors: cat odor, ferret odor, and trimethylthiazoline (a component of fox odor). Part 2 reviews the learning-based behavioral and neural adaptations that underlie predator odor-induced context conditioning, one-trial tolerance, sensitization, habituation and dishabituation. Copyright © 2010 Elsevier Inc. All rights reserved.

  13. Optogenetic stimulation of lateral amygdala input to posterior piriform cortex modulates single-unit and ensemble odor processing

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    Benjamin eSadrian

    2015-12-01

    Full Text Available Olfactory information is synthesized within the olfactory cortex to provide not only an odor percept, but also a contextual significance that supports appropriate behavioral response to specific odor cues. The piriform cortex serves as a communication hub within this circuit by sharing reciprocal connectivity with higher processing regions, such as the lateral entorhinal cortex and amygdala. The functional significance of these descending inputs on piriform cortical processing of odorants is currently not well understood. We have employed optogenetic methods to selectively stimulate lateral and basolateral amygdala (BLA afferent fibers innervating the posterior piriform cortex (pPCX to quantify BLA modulation of pPCX odor-evoked activity. Single unit odor-evoked activity of anaesthetized BLA-infected animals was significantly modulated compared with control animal recordings, with individual cells displaying either enhancement or suppression of odor-driven spiking. In addition, BLA activation induced a decorrelation of odor-evoked pPCX ensemble activity relative to odor alone. Together these results indicate a modulatory role in pPCX odor processing for the BLA complex, which could contribute to learned changes in PCX activity following associative conditioning.

  14. VOCs and odors: key factors in selecting `green` building materials?

    Energy Technology Data Exchange (ETDEWEB)

    Coombs, C. [Steven Winter Associates Inc., Norwalk, CT and Washington DC (United States)

    1998-12-01

    The current state of knowledge available for selecting building materials on the basis of emissions of volatile organic compounds (VOCs) and odors is reviewed. The significance of VOCs and odors in building materials is related to their role in influencing indoor air quality. As far as toxicity is concerned, many of the VOCs detected in indoor air are relatively inert when considered singly. They are not however, unimportant because in actual fact they are invariably found in mixtures some of which can be toxic. Although knowledge of VOCs is incomplete, it is important to specify ozone-resistant polymeric building products, i.e. those that are chemically stable and inert to oxidation. In addition to VOCs, attention should also be focused on semi-volatile organic compounds (SVOCs) since they are even more persistent than VOCs and tend to offgas for prolonged periods of time. Similarly, it is reasonable to specify low-odor materials. Inclusion of issues related to complex indoor chemistry, less volatile emissions, in addition to VOCs and odor, should in time result in expanded choices of building materials that promote indoor air quality. 16 refs.,2 tabs.

  15. Cyanotoxin mixtures and taste-and-odor compounds in cyanobacterial blooms from the midwestern united states

    Science.gov (United States)

    Graham, J.L.; Loftin, K.A.; Meyer, M.T.; Ziegler, A.C.

    2010-01-01

    The mixtures of toxins and taste-and-odor compounds present during cyanobacterial blooms are not well characterized and of particular concern when evaluating potential human health risks. Cyanobacterial blooms were sampled in twenty-three Midwestern United States lakes and analyzed for community composition, thirteen cyanotoxins by liquid chromatography/mass spectrometry and immunoassay, and two taste-and-odor compounds by gas chromatography/mass spectrometry. Aphanizomenon, Cylindrospermopsis and/or Microcystis were dominant in most (96%) blooms, but community composition was not strongly correlated with toxin and taste-and-odor occurrence. Microcystins occurred in all blooms. Total microcystin concentrations measured by liquid chromatography/mass spectrometry and immunoassay were linearly related (rs = 0.76, p cyanotoxins occurred in 48% of blooms and 95% had multiple microcystin variants. Toxins and taste-and-odor compounds frequently co-occurred (91% of blooms), indicating odor may serve as a warning that cyanotoxins likely are present. However, toxins occurred more frequently than taste-and-odor compounds, so odor alone does not provide sufficient warning to ensure human-health protection. ?? This article not subject to U.S. Copyright. Published 2010 by the American Chemical Society.

  16. An odor-specific threshold deficit implicates abnormal intracellular cyclic AMP signaling in schizophrenia.

    Science.gov (United States)

    Turetsky, Bruce I; Moberg, Paul J

    2009-02-01

    Although olfactory deficits are common in schizophrenia, their underlying pathophysiology remains unknown. Recent evidence has suggested that cAMP signaling may be disrupted in schizophrenia. Since cAMP mediates signal transduction in olfactory receptor neurons, this could contribute to the etiology of observed olfactory deficits. This study was designed to test this hypothesis by determining odor detection threshold sensitivities to two odorants that differ in their relative activations of this intracellular cAMP signaling cascade. Thirty schizophrenia patients, 25 healthy comparison subjects, and 19 unaffected first-degree relatives of schizophrenia patients were studied. Odor detection threshold sensitivities were measured for the two odorants citralva and lyral. Although both have fruity/floral scents, citralva strongly activates adenylyl cyclase to increase cAMP levels, while lyral is a very weak activator of adenylyl cyclase. There was a significant group-by-odor interaction. Both schizophrenia patients and unaffected first-degree relatives were impaired in their ability to detect lyral versus citralva. Comparison subjects were equally sensitive to both odorants. This selective deficit could not be explained by differences in age, sex, smoking, clinical symptom profile, or medication use. This study establishes the presence of an odor-specific hyposmia that may denote a disruption of cAMP-mediated signal transduction in schizophrenia. The presence of a parallel deficit in the patients' unaffected first-degree relatives suggests that this deficit is genetically mediated. Although additional physiological studies are needed to confirm the underlying mechanism, these results offer strong inferential support for the hypothesis that cAMP signaling is dysregulated in schizophrenia.

  17. Cholinergic Inputs from Basal Forebrain Add an Excitatory Bias to Odor Coding in the Olfactory Bulb

    Science.gov (United States)

    Rothermel, Markus; Carey, Ryan M.; Puche, Adam; Shipley, Michael T.

    2014-01-01

    Cholinergic modulation of central circuits is associated with active sensation, attention, and learning, yet the neural circuits and temporal dynamics underlying cholinergic effects on sensory processing remain unclear. Understanding the effects of cholinergic modulation on particular circuits is complicated by the widespread projections of cholinergic neurons to telencephalic structures that themselves are highly interconnected. Here we examined how cholinergic projections from basal forebrain to the olfactory bulb (OB) modulate output from the first stage of sensory processing in the mouse olfactory system. By optogenetically activating their axons directly in the OB, we found that cholinergic projections from basal forebrain regulate OB output by increasing the spike output of presumptive mitral/tufted cells. Cholinergic stimulation increased mitral/tufted cell spiking in the absence of inhalation-driven sensory input and further increased spiking responses to inhalation of odorless air and to odorants. This modulation was rapid and transient, was dependent on local cholinergic signaling in the OB, and differed from modulation by optogenetic activation of cholinergic neurons in basal forebrain, which led to a mixture of mitral/tufted cell excitation and suppression. Finally, bulbar cholinergic enhancement of mitral/tufted cell odorant responses was robust and occurred independent of the strength or even polarity of the odorant-evoked response, indicating that cholinergic modulation adds an excitatory bias to mitral/tufted cells as opposed to increasing response gain or sharpening response spectra. These results are consistent with a role for the basal forebrain cholinergic system in dynamically regulating the sensitivity to or salience of odors during active sensing of the olfactory environment. PMID:24672011

  18. Characterization of Odorant Compounds from Mechanical Aerated Pile Composting and Static Aerated Pile Composting

    Directory of Open Access Journals (Sweden)

    Priyanka Kumari

    2016-04-01

    Full Text Available We studied airborne contaminants (airborne particulates and odorous compounds emitted from compost facilities in South Korea. There are primarily two different types of composting systems operating in Korean farms, namely mechanical aerated pile composting (MAPC and aerated static pile composting (SAPC. In this study, we analyzed various particulate matters (PM10, PM7, PM2.5, PM1, and total suspended particles, volatile organic compounds and ammonia, and correlated these airborne contaminants with microclimatic parameters, i.e., temperature and relative humidity. Most of the analyzed airborne particulates (PM7, PM2.5, and PM1 were detected in high concentration at SAPC facilities compered to MAPC; however these differences were statistically non-significant. Similarly, most of the odorants did not vary significantly between MAPC and SAPC facilities, except for dimethyl sulfide (DMS and skatole. DMS concentrations were significantly higher in MAPC facilities, whereas skatole concentrations were significantly higher in SAPC facilities. The microclimate variables also did not vary significantly between MAPC and SAPC facilities, and did not correlate significantly with most of the airborne particles and odorous compounds, suggesting that microclimate variables did not influence their emission from compost facilities. These findings provide insight into the airborne contaminants that are emitted from compost facilities and the two different types of composting agitation systems.

  19. Novel odorant-binding proteins and their expression patterns in grasshopper, Oedaleus asiaticus.

    Science.gov (United States)

    Zhang, Shuo; Pang, Baoping; Zhang, Long

    2015-05-01

    Insects use olfaction to detect exogenous odors and adapt to environments. In their olfaction systems, odorant-binding proteins (OBPs) are believed to be a key component. The unique OBP system of each species reflects the evolution of chemosensation of insects with habits. Here, we for the first time identified 15 OBPs, OasiOBP1-15, of a grasshopper, Oedaleus asiaticus, that lives in the grasslands of Northern China and is closely related to the locust, Locusta migratoria. OasiOBP9 and OasiOBP10 are specifically expressed in the antennae. Other OBPs are expressed in the antennae as well as other chemosensory organs, such as the mouthparts and wings. Significantly more OasiOBP7 was detected in male than female antennae, but there are 9 OBPs that were more expressed in female than male antennae by quantitative real-time PCR. Phylogenetic analysis indicated that most of the O. asiaticus OBPs are similar to those of L. migratoria, but some are substantially different. This indicates that the OBPs originally evolved in a common ancestor, but their unique chemosensory systems are adapted to different ecosystems. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Separated set-systems and their geometric models

    Energy Technology Data Exchange (ETDEWEB)

    Danilov, Vladimir I; Koshevoy, Gleb A [Central Economics and Mathematics Institute, RAS, Moscow (Russian Federation); Karzanov, Aleksander V [Institute of Systems Analysis, Russian Academy of Sciences, Moscow (Russian Federation)

    2010-11-16

    This paper discusses strongly and weakly separated set-systems as well as rhombus tilings and wiring diagrams which are used to produce such systems. In particular, the Leclerc-Zelevinsky conjectures concerning weakly separated systems are proved. Bibliography: 54 titles.

  1. Simultaneous Sampling of Flow and Odorants by Crustaceans can Aid Searches within a Turbulent Plume

    Directory of Open Access Journals (Sweden)

    Swapnil Pravin

    2013-12-01

    Full Text Available Crustaceans such as crabs, lobsters and crayfish use dispersing odorant molecules to determine the location of predators, prey, potential mates and habitat. Odorant molecules diffuse in turbulent flows and are sensed by the olfactory organs of these animals, often using a flicking motion of their antennules. These antennules contain both chemosensory and mechanosensory sensilla, which enable them to detect both flow and odorants during a flick. To determine how simultaneous flow and odorant sampling can aid in search behavior, a 3-dimensional numerical model for the near-bed flow environment was created. A stream of odorant concentration was released into the flow creating a turbulent plume, and both temporally and spatially fluctuating velocity and odorant concentration were quantified. The plume characteristics show close resemblance to experimental measurements within a large laboratory flume. Results show that mean odorant concentration and it’s intermittency, computed as dc/dt, increase towards the plume source, but the temporal and spatial rate of this increase is slow and suggests that long measurement times would be necessary to be useful for chemosensory guidance. Odorant fluxes measured transverse to the mean flow direction, quantified as the product of the instantaneous fluctuation in concentration and velocity, v’c’, do show statistically distinct magnitude and directional information on either side of a plume centerline over integration times of <0.5 s. Aquatic animals typically have neural responses to odorant and velocity fields at rates between 50 and 500 ms, suggesting this simultaneous sampling of both flow and concentration in a turbulent plume can aid in source tracking on timescales relevant to aquatic animals.

  2. Selecting odorant compounds to enhance sweet flavor perception by gas chromatography/olfactometry-associated taste (GC/O-AT).

    Science.gov (United States)

    Barba, Carmen; Beno, Noelle; Guichard, Elisabeth; Thomas-Danguin, Thierry

    2018-08-15

    Gas chromatography/olfactometry-associated taste (GC/O-AT) analysis combined with mass spectrometry allowed identification of odorant compounds associated with taste attributes (sweet, salty, bitter and sour) in a multi-fruit juice. Nine compounds were selected for their odor-associated sweetness enhancement in a multi-fruit juice odor context using Olfactoscan and for their odor-induced sweet taste enhancement in sucrose solution and sugar-reduced fruit juice through sensory tests. Sweetness of the fruit juice odor was significantly enhanced by methyl 2-methylbutanoate, ethyl butanoate, ethyl 2-methylbutanoate and linalool; sweet perception was significantly enhanced in 7% sucrose solution by ethyl 2-methylbutanoate, furaneol and γ-decalactone, and in 32% sugar-reduced fruit juice by ethyl 2-methylbutanoate. GC/O-AT analysis is a novel, efficient approach to select odorants associated with a given taste. The further screening of taste-associated odorants by Olfactoscan helps to identify the most efficient odorants to enhance a target taste perception and may be used to find new ways to modulate taste perception in foods and beverages. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Douching With Water Works Device for Perceived Vaginal Odor With or Without Complaints of Discharge in Women With No Infectious Cause of Vaginitis: A Pilot Study

    Science.gov (United States)

    Chatwani, Ashwin J.; Hassan, Sarmina; Rahimi, Salma; Jeronis, Stacey; Dandolu, Vani

    2006-01-01

    Objective. To determine if douching with Water Works device for 1 month can (1) lower or eliminate perceived vaginal odor by subject; (2) have any effects on vaginal ecosystem. Methods. Ten women with perceived vaginal odor with or without discharge, douched every day for 4 weeks in an open-label, nonrandomized pilot study. Primary outcome measures included perceived vaginal odor by subject, lactobacilli score from Nugent slide, and acceptance of the Water Works douching system. Secondary outcome included the safety of using this douching device. Results. At week 4, there was improvement in vaginal odor (P = .0006) and there was no significant change in lactobacilli score. Conclusion. Douching with Water Works device is associated with reduction or elimination of vaginal odor without adversely affecting the vaginal ecosystem. PMID:17485816

  4. Odor Memory and Discrimination Covary as a Function of Delay between Encoding and Recall in Rats.

    Science.gov (United States)

    Hackett, Chelsea; Choi, Christina; O'Brien, Brenna; Shin, Philip; Linster, Christiane

    2015-06-01

    Nonassociative odor learning paradigms are often used to assess memory, social recognition and neuromodulation of olfactory pathways. We here use a modified object recognition paradigm to investigate how an important task parameter, delay between encoding and recall trials, affects the properties of this memory. We show that both memory for a previously investigated odorant and discrimination of a novel odorant decay with delay time and that rats can remember an odorant for up to 45min after a single trial encoding event. The number of odorants that can be encoded, as well as the specificity of the encoded memory, decrease with increased delay and also depend on stimulus concentration. Memory for an odorant and discrimination of a novel odorant decay at approximately the same rate, whereas the specificity of the formed memory decays faster than the memory itself. These results have important implications for the interpretation of behavioral data obtained with this paradigm. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Maternal and littermate deprivation disrupts maternal behavior and social-learning of food preference in adulthood: tactile stimulation, nest odor, and social rearing prevent these effects.

    Science.gov (United States)

    Melo, Angel I; Lovic, Vedran; Gonzalez, Andrea; Madden, Melissa; Sinopoli, Katia; Fleming, Alison S

    2006-04-01

    Maternal and littermate (social) separation, through artificial rearing (AR), disrupts the development of subsequent maternal behavior and social learning in rats. The addition of maternal-licking-like stimulation during AR, partially reverses some of these effects. However, little is know about the role of social stimuli from littermates and nest odors during the preweaning period, in the development of the adult maternal behavior and social learning. The purpose of this study was to examine the effects of peer- and peer-and-odor rearing on the development of maternal behavior and social learning in rats. Female pups were reared with mothers (mother reared-MR) or without mothers (AR) from postnatal day (PND) 3. AR rats received three different treatments: (1) AR-CONTROL group received minimal tactile stimulation, (2) AR-ODOR females received exposure to maternal nest material inside the AR-isolation-cup environment, (3) AR-SOCIAL group was reared in the cup with maternal nest material and a conspecific of the same-age and same-sex and received additional tactile stimulation. MR females were reared by their mothers in the nest and with conspecifics. In adulthood, rats were tested for maternal behavior towards their own pups and in a social learning task. Results confirm our previous report that AR impairs performance of maternal behavior and the development of a social food preference. Furthermore, social cues from a littermate, in combination with tactile stimulation and the nest odor, reversed the negative effects of complete isolation (AR-CONTROL) on some of the above behaviors. Exposure to the odor alone also had effects on some of these olfactory-mediated behaviors. These studies indicate that social stimulation from littermates during the preweaning period, in combination with odor from the nest and tactile stimulation, contributes to the development of affiliative behaviors. Copyright (c) 2006 Wiley Periodicals, Inc.

  6. Pleasantness, familiarity, and identification of spice odors are interrelated and enhanced by consumption of herbs and food neophilia.

    Science.gov (United States)

    Knaapila, Antti; Laaksonen, Oskar; Virtanen, Markus; Yang, Baoru; Lagström, Hanna; Sandell, Mari

    2017-02-01

    The primary dimension of odor is pleasantness, which is associated with a multitude of factors. We investigated how the pleasantness, familiarity, and identification of spice odors were associated with each other and with the use of the respective spice, overall use of herbs, and level of food neophobia. A total of 126 adults (93 women, 33 men; age 25-61 years, mean 39 years) rated the odors from 12 spices (oregano, anise, rosemary, mint, caraway, sage, thyme, cinnamon, fennel, marjoram, garlic, and clove) for pleasantness and familiarity, and completed a multiple-choice odor identification. Data on the use of specific spices, overall use of herbs, and Food Neophobia Scale score were collected using an online questionnaire. Familiar odors were mostly rated as pleasant (except garlic), whereas unfamiliar odors were rated as neutral (r = 0.63). We observed consistent and often significant trends that suggested the odor pleasantness and familiarity were positively associated with the correct odor identification, consumption of the respective spice, overall use of herbs, and food neophilia. Our results suggest that knowledge acquisition through repetitive exposure to spice odor with active attention may gradually increase the odor pleasantness within the framework set by the chemical characteristics of the aroma compound. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Lesions that functionally disconnect the anterior and posterodorsal sub-regions of the medial amygdala eliminate opposite-sex odor preference in male Syrian hamsters (Mesocricetus auratus)

    Science.gov (United States)

    Maras, Pamela M.; Petrulis, Aras

    2009-01-01

    In many rodent species, such as Syrian hamsters, reproductive behavior requires neural integration of chemosensory information and steroid hormone cues. The medial amygdala processes both of these signals through anatomically distinct sub-regions; the anterior region (MeA) receives substantial chemosensory input, but contains few steroid receptor-labeled neurons, whereas the posterodorsal region (MePD) receives less chemosensory input, but contains a dense population of steroid receptors. Importantly, these sub-regions have considerable reciprocal connections, and the goal of this experiment was therefore to determine whether interactions between MeA and MePD are required for male hamsters’ preference to investigate female over male odors. To functionally disconnect MeA and MePD, males received unilateral lesions of MeA and MePD within opposite brain hemispheres. Control males received either unilateral lesions of MeA and MePD within the same hemisphere or sham surgery. Odor preferences were measured using a 3-choice apparatus, which simultaneously presented female, male and clean odor stimuli; all tests were done under conditions that either prevented or allowed contact with the odor sources. Under non-contact conditions, males with asymmetrical lesions investigated female and male odors equally, whereas males in both control groups preferred to investigate female odors. Under contact conditions, all groups investigated female odors longer than male odors, although males with asymmetrical lesions displayed decreased investigation of female odors compared to sham males. These data suggest that MeA-MePD interactions are critical for processing primarily the volatile components of social odors and highlight the importance of input from the main olfactory system to these nuclei in the regulation of reproductive behavior. More broadly, these results support the role of the medial amygdala in integrating chemosensory and hormone information, a process that may

  8. [Evaluation of treatment technology of odor pollution source in petrochemical industry].

    Science.gov (United States)

    Mu, Gui-Qin; Sui, Li-Hua; Guo, Ya-Feng; Ma, Chuan-Jun; Yang, Wen-Yu; Gao, Yang

    2013-12-01

    Using an environmental technology assessment system, we put forward the evaluation index system for treatment technology of the typical odor pollution sources in the petroleum refining process, which has been applied in the assessment of the industrial technology. And then the best available techniques are selected for emissions of gas refinery sewage treatment plant, headspace gas of acidic water jars, headspace gas of cold coke jugs/intermediate oil tank/dirty oil tank, exhaust of oxidative sweetening, and vapors of loading and unloading oil.

  9. Individual odor recognition in birds: an endogenous olfactory signature on petrels' feathers?

    Science.gov (United States)

    Bonadonna, Francesco; Miguel, Eve; Grosbois, Vladimir; Jouventin, Pierre; Bessiere, Jean-Marie

    2007-09-01

    A growing body of evidence indicates that odors are used in individual, sexual, and species recognition in vertebrates, and may be reliable signals of quality and compatibility. Petrels are seabirds that exhibit an acute sense of smell. During the breeding period, many species of petrels live in dense colonies on small oceanic islands and form pairs that use individual underground burrows. Mates alternate between parental duties and foraging trips at sea. Returning from the ocean at night (to avoid bird predators), petrels must find their nest burrow. Antarctic prions, Pachyptila desolata, are thought to identify their nest by recognizing their partner's odor, suggesting the existence of an individual odor signature. We used gas chromatography and mass spectrometry to analyze extracts obtained from the feathers of 13 birds. The chemical profile of a single bird was more similar to itself, from year to year, than to that of any other bird. The profile contained up to a hundred volatile lipids, but the odor signature may be based on the presence or absence of a few specific compounds. Our results show that the odor signature in Antarctic prions is probably endogenous, suggesting that in some species of petrels it may broadcast compatibility and quality of potential mates.

  10. [Primary trimethylaminuria: the fish odor syndrome

    NARCIS (Netherlands)

    Montoya Alvarez, T.; Guardiola, P.; Roldan, J.O.; Elviro, R.; Wevers, R.A.; Guijarro, G.

    2009-01-01

    Primary trimethylaminuria, or fish odor syndrome, is a congenital metabolic disorder characterized by a failure in the hepatic trimethylamine (TMA) oxidation route to trimethylamine N-oxide (TMANO). TMA is mostly derived from dietary precursors such as choline, carnitine and TMANO. The presence of

  11. Isotope separation in crossed-jet systems

    Energy Technology Data Exchange (ETDEWEB)

    Gallagher, R.J.; Anderson, J.B.

    1978-11-01

    The separation of isotopes in crossed-jet systems was investigated with Monte Carlo calculations of the separation effects for jets of Ne/Ar and /sup 235/UF/sub 6///sup 238/UF/sub 6/ mixtures entering a hydrogen stream. For the ideal condition of uniform stream velocities at zero temperature, the separation factor ..cap alpha.. was found to be 16.0 for Ne/Ar and 1.17 for /sup 235/UF/sub 6///sup 238/UF/sub 6/. For less ideal but more practical conditions, Monte Carlo calculations of the complete crossed-jet systems gave separation factors as high as 3.3 for Ne/Ar and ..cap alpha.. = 1.046 - 1.078 for /sup 235/UF/sub 6///sup 238/UF/sub 6/.

  12. Methods of human body odor sampling: the effect of freezing.

    Science.gov (United States)

    Lenochova, Pavlina; Roberts, S Craig; Havlicek, Jan

    2009-02-01

    Body odor sampling is an essential tool in human chemical ecology research. However, methodologies of individual studies vary widely in terms of sampling material, length of sampling, and sample processing. Although these differences might have a critical impact on results obtained, almost no studies test validity of current methods. Here, we focused on the effect of freezing samples between collection and use in experiments involving body odor perception. In 2 experiments, we tested whether axillary odors were perceived differently by raters when presented fresh or having been frozen and whether several freeze-thaw cycles affected sample quality. In the first experiment, samples were frozen for 2 weeks, 1 month, or 4 months. We found no differences in ratings of pleasantness, attractiveness, or masculinity between fresh and frozen samples. Similarly, almost no differences between repeatedly thawed and fresh samples were found. We found some variations in intensity; however, this was unrelated to length of storage. The second experiment tested differences between fresh samples and those frozen for 6 months. Again no differences in subjective ratings were observed. These results suggest that freezing has no significant effect on perceived odor hedonicity and that samples can be reliably used after storage for relatively long periods.

  13. Cognitive Load Alters Neuronal Processing of Food Odors.

    Science.gov (United States)

    Hoffmann-Hensel, Sonja Maria; Sijben, Rik; Rodriguez-Raecke, Rea; Freiherr, Jessica

    2017-10-31

    Obesity is a major health concern in modern societies. Although decreased physical activity and enhanced intake of high-caloric foods are important risk factors for developing obesity, human behavior during eating also plays a role. Previous studies have shown that distraction while eating increases food intake and leads to impaired processing of food stimuli. As olfaction is the most important sense involved in flavor perception, we used functional magnetic resonance imaging techniques to investigate the influence of cognitive memory load on olfactory perception and processing. Low- and high-caloric food odors were presented in combination with either low or high cognitive loads utilizing a memory task. The efficacy of the memory task was verified by a decrease in participant recall accuracy and an increase in skin conductance response during high cognitive load. Our behavioral data reveal a diminished perceived intensity for low- but not high-caloric food odors during high cognitive load. For low-caloric food odors, bilateral orbitofrontal (OFC) and piriform cortices (pirC) showed significantly lower activity during high compared with low cognitive load. For high-caloric food odors, a similar effect was established in pirC, but not in OFC. Insula activity correlates with higher intensity ratings found during the low cognitive load condition. We conclude lower activity in pirC and OFC to be responsible for diminished intensity perception, comparable to results in olfactory impaired patients and elderly. Further studies should investigate the influence of olfactory/gustatory intensities on food choices under distraction with special regards to low-caloric food. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Stability of odorants from pig production in sampling bags for olfactometry.

    Science.gov (United States)

    Hansen, Michael J; Adamsen, Anders P S; Feilberg, Anders; Jonassen, Kristoffer E N

    2011-01-01

    Odor from pig production facilities is typically measured with olfactometry, whereby odor samples are collected in sampling bags and assessed by human panelists within 30 h. In the present study, the storage stability of odorants in two types of sampling bags that are often used for olfactometry was investigated. The bags were made of Tedlar or Nalophan. In a field experiment, humid and dried air samples were collected from a pig production facility with growing-finishing pigs and analyzed with a gas chromatograph with an amperometric sulfur detector at 4, 8, 12, 28, 52, and 76 h after sampling. In a laboratory experiment, the bags were filled with a humid gas mixture containing carboxylic acids, phenols, indoles, and sulfur compounds and analyzed with proton-transfer-reaction mass spectrometry after 0, 4, 8, 12, and 24 h. The results demonstrated that the concentrations of carboxylic acids, phenols, and indoles decreased by 50 to >99% during the 24 h of storage in Tedlar and Nalophan bags. The concentration of hydrogen sulfide decreased by approximately 30% during the 24 h of storage in Nalophan bags, whereas in Tedlar bags the concentration of sulfur compounds decreased by bags, and the composition changes toward a higher relative presence of sulfur compounds. This can result in underestimation of odor emissions from pig production facilities and of the effect of odor reduction technologies. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  15. Application of Odor Sensors to Ore Sorting and Mill Feed Control

    Energy Technology Data Exchange (ETDEWEB)

    Michael G. Nelson

    2005-08-01

    Control of the feed provided to mineral processing facilities is a continuing challenge. Much effort is currently being devoted to overcoming these problems. These projects are usually described under the general headings of Mine-to-Mill Integration or Mine-Mill Optimization. It should be possible to combine the knowledge of ore type, mineralogy, and other characteristics (located in the mine modeling system), with the advanced capabilities of state-of-the-art mill control systems, to achieve an improved level of control in mineral processing that will allow optimization of the mill processes on an almost real-time basis. This is not happening because mill feed it is often treated as a uniform material, when in reality it varies in composition and characteristics. An investigation was conducted to assess the suitability of odor sensors for maintaining traceability in ore production and processing. Commercially available sensors are now used in food processing, environmental monitoring, and other applications and can detect the presence of very small amounts (0.1-500 ppm) of some molecules. An assortment of such molecules could be used to ''tag'' blocks of ore as they are mined, according to their respective characteristics. Then, as the ore came into the mill, an array of ''electronic noses'' could be used to assess its characteristics in real time. It was found that the Cyranose 320{trademark}, a commercially available odor sensor, can easily distinguish among samples of rock marked with almond, cinnamon, citronella, lemon, and orange oils. Further, the sensor could detect mixtures of rocks marked with various combinations of these oils. Treatment of mixtures of galena and silica with odorant compounds showed no detrimental effects on flotation response in laboratory tests. Additional work is recommended to determine how this concept can be extended to the marking of large volumes of materials.

  16. Regional integrated system of separated collection

    International Nuclear Information System (INIS)

    Markuskova, I.

    2008-01-01

    Since 2002 Palarikovo manages and ensures Regional integrated system of separated collection. In the present time 28 villages of the region are associated in Association of villages for sustainable treatment of municipal wastes with settlement in Palarikovo. In accordance with hierarchy of goals of national strategy in the field of treatment of municipal wastes the key aims of activity are centred on economical and sustainable treatment of municipal wastes, which consist in reduction of quantity and harmfulness of municipal wastes by destruction by unloading or combustion. The steps for achievement of this aim consist in (1) prevention of formation of wastes, (2) using of usable subjects (establishing of centre for repeated using in Regional collecting court), (3) by rigorous realisation of recycling program - by collection of separated commodities with a view to mainly material recycling as well as composting program. By starting of integrated regional system of separated collection were integrated 18 villages with 24,000 inhabitants into common separated collection. In the present time this association has 28 members (villages of the region) with total population 55,904. Operating of the Regional integrated system of separated collection in Palarikovo is reviewed

  17. Dubowitz syndrome: common findings and peculiar urine odor

    Directory of Open Access Journals (Sweden)

    Chehade C

    2013-10-01

    Full Text Available Cynthia Chehade,1 Johnny Awwad,2 Nadine Yazbeck,1 Marianne Majdalani,1 Rima Wakim,1 Hala Tfayli,1 Chantal Farra1,31Department of Pediatrics and Adolescent Medicine, American University of Beirut Medical Center, Beirut, Lebanon; 2Department of Obstetrics and Gynecology, American University of Beirut Medical Center, Beirut, Lebanon; 3Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Beirut, LebanonBackground: Dubowitz syndrome is a rare, autosomal recessive disorder characterized by intrauterine and postnatal growth retardation, severe microcephaly, psychomotor retardation, hyperactivity, eczema, and characteristic dysmorphic facial features. Although many cases have been reported, the cause of this disease is still unknown.Case: We present here the case of a Lebanese girl with Dubowitz syndrome in whom an unpleasant urine odor was persistently reported since birth.Conclusion: Although Dubowitz syndrome has been largely described in the medical literature, this is the first time that a peculiar urine odor was reported. This case report adds a new and unusual feature to the numerous findings related to this rare polymorphous syndrome.Keywords: Dubowitz syndrome, autosomal recessive, developmental delay, odorous urine

  18. Topological reorganization of odor representations in the olfactory bulb.

    Directory of Open Access Journals (Sweden)

    Emre Yaksi

    2007-07-01

    Full Text Available Odors are initially represented in the olfactory bulb (OB by patterns of sensory input across the array of glomeruli. Although activated glomeruli are often widely distributed, glomeruli responding to stimuli sharing molecular features tend to be loosely clustered and thus establish a fractured chemotopic map. Neuronal circuits in the OB transform glomerular patterns of sensory input into spatiotemporal patterns of output activity and thereby extract information about a stimulus. It is, however, unknown whether the chemotopic spatial organization of glomerular inputs is maintained during these computations. To explore this issue, we measured spatiotemporal patterns of odor-evoked activity across thousands of individual neurons in the zebrafish OB by temporally deconvolved two-photon Ca(2+ imaging. Mitral cells and interneurons were distinguished by transgenic markers and exhibited different response selectivities. Shortly after response onset, activity patterns exhibited foci of activity associated with certain chemical features throughout all layers. During the subsequent few hundred milliseconds, however, MC activity was locally sparsened within the initial foci in an odor-specific manner. As a consequence, chemotopic maps disappeared and activity patterns became more informative about precise odor identity. Hence, chemotopic maps of glomerular input activity are initially transmitted to OB outputs, but not maintained during pattern processing. Nevertheless, transient chemotopic maps may support neuronal computations by establishing important synaptic interactions within the circuit. These results provide insights into the functional topology of neural activity patterns and its potential role in circuit function.

  19. Cat odor causes long-lasting contextual fear conditioning and increased pituitary-adrenal activation, without modifying anxiety.

    Science.gov (United States)

    Muñoz-Abellán, Cristina; Daviu, Nuria; Rabasa, Cristina; Nadal, Roser; Armario, Antonio

    2009-10-01

    A single exposure to a cat or cat odors has been reported by some groups to induce contextual and auditory fear conditioning and long-lasting changes in anxiety-like behaviour, but there is no evidence for parallel changes in biological stress markers. In the present study we demonstrated in male rats that exposure to a novel environment containing a cloth impregnated with cat fur odor resulted in avoidance of the odor, lower levels of activity and higher pituitary-adrenal (PA) response as compared to those exposed to the novel environment containing a clean cloth, suggesting increased levels of stress in the former animals. When re-exposed 9 days later to the same environment with a clean cloth, previously cat fur exposed rats again showed avoidance of the cloth area and lower levels of activity, suggesting development of contextual fear conditioning, which again was associated with a higher PA activation. In contrast, unaltered both anxiety-like behaviour and PA responsiveness to an elevated plus-maze were found 7 days after cat odor exposure. It is concluded that: (i) PA activation is able to reflect both the stressful properties of cat fur odor and odor-induced contextual fear conditioning; (ii) development of cat odor-induced contextual fear conditioning is independent of the induction of long-lasting changes in anxiety-like behaviour; and (iii) greater PA activation during exposure to the odor context is not explained by non-specific sensitization of the PA axis caused by previous exposure to cat fur odor.

  20. Odorants and malodors associated with land application of biosolids stabilized with lime and coal fly ash.

    Science.gov (United States)

    Laor, Yael; Naor, Moshe; Ravid, Uzi; Fine, Pinchas; Halachmi, Ilan; Chen, Yona; Baybikov, Rima

    2011-01-01

    Malodor emissions limit public acceptance of using municipal biosolids as natural organic resources in agricultural production. We aimed to identify major odorants and to evaluate odor concentrations associated with land application of anaerobically digested sewage sludges (Class B) and their alkaline (lime and coal fly ash)-stabilized products (Class A). These two types of biosolids were applied at 12.6 tonnes ha(-1) (dry weight) to microplots of very fine clayey Vertisol in the Jezreel Valley, northern Israel. The volatile organic compounds (VOCs) emitted from the biosolids before and during alkaline stabilization and after incorporation into the soil were analyzed by headspace solid-phase microextraction followed by gas chromatography-mass spectrometry. Odor concentrations at the plots were evaluated on site with a Nasal Ranger field olfactometer that sniffed over a defined land surface area through a static chamber. The odors emitted by anaerobically digested sewage sludges from three activated sludge water treatment plants had one characteristic chemical fingerprint. Alkaline stabilization emitted substantial odors associated with high concentrations of ammonia and release of nitrogen-containing VOCs and did not effectively reduce the potential odor annoyance. Odorous VOCs could be generated within the soil after biosolids incorporation, presumably because of anaerobic conditions within soil-biosolids aggregates. We propose that dimethyl disulfide and dimethyl trisulfide, which seem to be most related to the odor concentrations of biosolids-treated soil, be used as potential chemical markers for the odor annoyance associated with incorporation of anaerobically digested sewage sludges. by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. Psychology of fragrance use: perception of individual odor and perfume blends reveals a mechanism for idiosyncratic effects on fragrance choice.

    Science.gov (United States)

    Lenochová, Pavlína; Vohnoutová, Pavla; Roberts, S Craig; Oberzaucher, Elisabeth; Grammer, Karl; Havlíček, Jan

    2012-01-01

    Cross-culturally, fragrances are used to modulate body odor, but the psychology of fragrance choice has been largely overlooked. The prevalent view is that fragrances mask an individual's body odor and improve its pleasantness. In two experiments, we found positive effects of perfume on body odor perception. Importantly, however, this was modulated by significant interactions with individual odor donors. Fragrances thus appear to interact with body odor, creating an individually-specific odor mixture. In a third experiment, the odor mixture of an individual's body odor and their preferred perfume was perceived as more pleasant than a blend of the same body odor with a randomly-allocated perfume, even when there was no difference in pleasantness between the perfumes. This indicates that fragrance use extends beyond simple masking effects and that people choose perfumes that interact well with their own odor. Our results provide an explanation for the highly individual nature of perfume choice.

  2. Sniffing the mood for cooperation: Personality and odor induced affective states effects

    Directory of Open Access Journals (Sweden)

    Marchlewska Marta

    2016-06-01

    Full Text Available The paper explores situational and dispositional underpinnings of cooperative behavior. According to psychological research, cooperation is strongly related to affective states (Forgas, 1998 and personality dimensions (Volk, Thöni, & Ruigrok, 2011. In an experimental study we examined the conditions under which people cooperate with each other. The dispositional traits of co-workers (personality, the contribution to a collaborative effort, and a situational factor – ambient odor condition were taken into consideration. A one-way ANOVA revealed that compared to a malodorous condition, both the pleasant odor condition and the natural odor condition showed higher rates of cooperation. Further analysis indicated that only malodors influenced affective states which in turn determined social decisions. Although we found effects for the participants’ agreeableness and the coworker’s contribution to a joint work, they appeared to play a less critical role than affective states induced by the experimental odor conditions tested here.

  3. Estimation of Separation Buffers for Wind-Prediction Error in an Airborne Separation Assistance System

    Science.gov (United States)

    Consiglio, Maria C.; Hoadley, Sherwood T.; Allen, B. Danette

    2009-01-01

    Wind prediction errors are known to affect the performance of automated air traffic management tools that rely on aircraft trajectory predictions. In particular, automated separation assurance tools, planned as part of the NextGen concept of operations, must be designed to account and compensate for the impact of wind prediction errors and other system uncertainties. In this paper we describe a high fidelity batch simulation study designed to estimate the separation distance required to compensate for the effects of wind-prediction errors throughout increasing traffic density on an airborne separation assistance system. These experimental runs are part of the Safety Performance of Airborne Separation experiment suite that examines the safety implications of prediction errors and system uncertainties on airborne separation assurance systems. In this experiment, wind-prediction errors were varied between zero and forty knots while traffic density was increased several times current traffic levels. In order to accurately measure the full unmitigated impact of wind-prediction errors, no uncertainty buffers were added to the separation minima. The goal of the study was to measure the impact of wind-prediction errors in order to estimate the additional separation buffers necessary to preserve separation and to provide a baseline for future analyses. Buffer estimations from this study will be used and verified in upcoming safety evaluation experiments under similar simulation conditions. Results suggest that the strategic airborne separation functions exercised in this experiment can sustain wind prediction errors up to 40kts at current day air traffic density with no additional separation distance buffer and at eight times the current day with no more than a 60% increase in separation distance buffer.

  4. Analysis of the application of selected physico-chemical methods in eliminating odor nuisance of municipal facilities

    Directory of Open Access Journals (Sweden)

    Miller Urszula

    2018-01-01

    Full Text Available Operation of municipal management facilities is inseparable from the problem of malodorous compounds emissions to the atmospheric air. In that case odor nuisance is related to the chemical composition of waste, sewage and sludge as well as to the activity of microorganisms whose products of life processes can be those odorous compounds. Significant reduction of odorant emission from many sources can be achieved by optimizing parameters and conditions of processes. However, it is not always possible to limit the formation of odorants. In such cases it is best to use appropriate deodorizing methods. The choice of the appropriate method is based on in terms of physical parameters, emission intensity of polluted gases and their composition, if it is possible to determine. Among the solutions used in municipal economy, there can be distinguished physico-chemical methods such as sorption and oxidation. In cases where the source of the emission is not encapsulated, odor masking techniques are used, which consists of spraying preparations that neutralize unpleasant odors. The paper presents the characteristics of selected methods of eliminating odor nuisance and evaluation of their applicability in municipal management facilities.

  5. Analysis of the application of selected physico-chemical methods in eliminating odor nuisance of municipal facilities

    Science.gov (United States)

    Miller, Urszula; Grzelka, Agnieszka; Romanik, Elżbieta; Kuriata, Magdalena

    2018-01-01

    Operation of municipal management facilities is inseparable from the problem of malodorous compounds emissions to the atmospheric air. In that case odor nuisance is related to the chemical composition of waste, sewage and sludge as well as to the activity of microorganisms whose products of life processes can be those odorous compounds. Significant reduction of odorant emission from many sources can be achieved by optimizing parameters and conditions of processes. However, it is not always possible to limit the formation of odorants. In such cases it is best to use appropriate deodorizing methods. The choice of the appropriate method is based on in terms of physical parameters, emission intensity of polluted gases and their composition, if it is possible to determine. Among the solutions used in municipal economy, there can be distinguished physico-chemical methods such as sorption and oxidation. In cases where the source of the emission is not encapsulated, odor masking techniques are used, which consists of spraying preparations that neutralize unpleasant odors. The paper presents the characteristics of selected methods of eliminating odor nuisance and evaluation of their applicability in municipal management facilities.

  6. Assessment of the aroma impact of major odor-active thiols in pan-roasted white sesame seeds by calculation of odor activity values.

    Science.gov (United States)

    Tamura, Hitoshi; Fujita, Akira; Steinhaus, Martin; Takahisa, Eisuke; Watanabe, Hiroyuki; Schieberle, Peter

    2011-09-28

    Eleven odor-active thiols, namely, 2-methyl-1-propene-1-thiol, (Z)-3-methyl-1-butene-1-thiol, (E)-3-methyl-1-butene-1-thiol, (Z)-2-methyl-1-butene-1-thiol, (E)-2-methyl-1-butene-1-thiol, 2-methyl-3-furanthiol, 3-mercapto-2-pentanone, 2-mercapto-3-pentanone, 4-mercapto-3-hexanone, 3-mercapto-3-methylbutyl formate, and 2-methyl-3-thiophenethiol, recently identified in an extract prepared from white sesame seeds, were quantitated in sesame using stable isotope dilution analyses. For that purpose, the following deuterium-labeled compounds were synthesized and used as internal standards in the quantitation assays: [2H6]-2-methyl-1-propene-1-thiol, [2H3]-(E)- and [2H3]-(Z)-2-methyl-1-butene-1-thiol, [2H3]-2-methyl-3-furanthiol, [2H2]-3-mercapto-2-pentanone, [2H3]-4-mercapto-3-hexanone, [2H6]-3-mercapto-3-methylbutyl formate, and [2H3]-2-methyl-3-thiophenethiol. On the basis of the results obtained, odor activity values (OAVs) were calculated as ratio of the concentration and odor threshold of the individual compounds in cooking oil. According to their high OAVs, particularly the 3-methyl-1-butene-1-thiols (OAV: 2400) and the 2-methyl-1-butene-1-thiols (OAV: 960) were identified as the most odor-active compounds in pan-roasted white sesame seeds. These compounds were therefore suggested to be mainly responsible for the characteristic but rather unstable sulfury aroma of freshly pan-roasted white sesame seeds.

  7. How Far Does a Receptor Influence Vibrational Properties of an Odorant?

    DEFF Research Database (Denmark)

    Reese, Anna; List, Nanna Holmgaard; Kongsted, Jacob

    2016-01-01

    -assisted electron transfer. Through molecular dynamics simulations we elucidate the binding specificity of a receptor towards acetophenone odorant. The vibrational properties of acetophenone inside the receptor are then studied by the polarizable embedding density functional theory approach, allowing to quantify...... protein-odorant interactions. Finally, we judge whether the effects of the protein provide any indications towards the existing theories of olfaction....

  8. Estudos sôbre os órgãos odoríferos de alguns Hesperidae Brasileiros

    Directory of Open Access Journals (Sweden)

    Rudolf Barth

    1952-03-01

    Full Text Available 1. São descritas áreas de escamas nas asas do macho e da fêmea de várias espécies de Hesperidae brasilienses. 2. É considerada a corelação destas áreas as articulações entre as asas anteriores e posteriores. 3. Verificou-se que as áreas das escamas odoríferas da asa posterior têm origem nas áreas das escamas de ligação. Esta mudança de função é demonstrada pela forma das escamas em comparação com escamas de ligação em função. 4. É apresentada uma descrição detalhada da estrutura mais fina das escamas de ligação e das escamas odoríferas. 5. As borboletas de sexo masculino das espécies examinadas podem ser divididas de acôrdo com a ausência ou presença de órgãos odoríferos diferentes (v. tabela 1: 1. grupo: borboletas sem glândulas odoríferas especiais (tipo de Vehilius. 2. grupo: borboletas com sulco odorífero na asa anterior (tipo de Augiades 3. grupo: borboletas com dobra costal da asa anterior (tipo de Thanaos. 4. grupo: borboletas com órgão odorífero no metatórax (tipo de Achlyodes. 6. A fêmea de H 31 possui na memebrana intersegmental VII./VIII. escamas odoríferas de uma notável estrutura mais fina. 7. As escamas odoríferas são estudadas com respeito à sua estrutura fina e dada uma possível derivação da cerda da escama. 8. O estudo dos órgãos odoríferos é feito com respeito ao aumento da superfície destinada á evaporação pelas escamas e ainda á função protetora das escamas de cobertura e dobras cuticulares. 9. A evolução de órgãos odoríferos diferentes em diferentes partes do corpo indica uma evolução polifilética dos órgãos, o que tem valor sistemático na família bem limitada das Hesperidae. 10. Os machos de h 16 e H 130 possuem dois tipos de órgãos odoríferos especiais, a dobra costal e o órgão odorífero do metatórax com pincel-distribuidor na tíbia posterior. Nas espécies citadas e que têm parentesco, toma lugar uma evolução polifilética de

  9. Posttraining ablation of adult-generated olfactory granule cells degrades odor-reward memories.

    Science.gov (United States)

    Arruda-Carvalho, Maithe; Akers, Katherine G; Guskjolen, Axel; Sakaguchi, Masanori; Josselyn, Sheena A; Frankland, Paul W

    2014-11-19

    Proliferation of neural progenitor cells in the subventricular zone leads to the continuous generation of new olfactory granule cells (OGCs) throughout life. These cells synaptically integrate into olfactory bulb circuits after ∼2 weeks and transiently exhibit heightened plasticity and responses to novel odors. Although these observations suggest that adult-generated OGCs play important roles in olfactory-related memories, global suppression of olfactory neurogenesis does not typically prevent the formation of odor-reward memories, perhaps because residual OGCs can compensate. Here, we used a transgenic strategy to selectively ablate large numbers of adult-generated OGCs either before or after learning in mice. Consistent with previous studies, pretraining ablation of adult-generated OGCs did not prevent the formation of an odor-reward memory, presumably because existing OGCs can support memory formation in their absence. However, ablation of a similar cohort of adult-generated OGCs after training impaired subsequent memory expression, indicating that if these cells are available at the time of training, they play an essential role in subsequent expression of odor-reward memories. Memory impairment was associated with the loss of adult-generated OGCs that were >10 d in age and did not depend on the developmental stage in which they were generated, suggesting that, once sufficiently mature, OGCs generated during juvenility and adulthood play similar roles in the expression of odor-reward memories. Finally, ablation of adult-generated OGCs 1 month after training did not produce amnesia, indicating that adult-generated OGCs play a time-limited role in the expression of odor-reward memories. Copyright © 2014 the authors 0270-6474/14/3415793-11$15.00/0.

  10. Process and technological options for odorous emissions control in wastewater treatment plants

    International Nuclear Information System (INIS)

    Cernuschi, S.; Torretta, V.

    1996-01-01

    The emissions of odorous substances together with noise and issues related to proper architectural design within the existing territorial context, have certainly to be considered one of the most significant environmental effects determined by wastewater treatment plants particularly in the most frequent case of their localization in dense urban areas. Following a brief introduction on the chemical properties of odorous compounds and the corresponding methods for representing their concentration levels in air, present work reports on the main qualitative and quantitative characteristics of odorous emissions originating from single unit operations of typical wastewater treatment plants and on the technological and process options available for their control

  11. Blind speech separation system for humanoid robot with FastICA for audio filtering and separation

    Science.gov (United States)

    Budiharto, Widodo; Santoso Gunawan, Alexander Agung

    2016-07-01

    Nowadays, there are many developments in building intelligent humanoid robot, mainly in order to handle voice and image. In this research, we propose blind speech separation system using FastICA for audio filtering and separation that can be used in education or entertainment. Our main problem is to separate the multi speech sources and also to filter irrelevant noises. After speech separation step, the results will be integrated with our previous speech and face recognition system which is based on Bioloid GP robot and Raspberry Pi 2 as controller. The experimental results show the accuracy of our blind speech separation system is about 88% in command and query recognition cases.

  12. Differential odor processing in two olfactory pathways in the honeybee

    Directory of Open Access Journals (Sweden)

    Nobuhiro Yamagata

    2009-12-01

    Full Text Available An important component in understanding central olfactory processing and coding in the insect brain relates to the characterization of the functional divisions between morphologically distinct types of projection neurons (PN. Using calcium imaging, we investigated how the identity, concentration and mixtures of odors are represented in axon terminals (boutons of two types of PNs - lPN and mPN. In lPN boutons we found less concentration dependence, narrow tuning profiles at a high concentration, which may be optimized for fine, concentration-invariant odor discrimination. In mPN boutons, however, we found clear rising concentration dependence, broader tuning profiles at a high concentration, which may be optimized for concentration coding. In addition, we found more mixture suppression in lPNs than in mPNs, indicating lPNs better adaptation for synthetic mixture processing. These results suggest a functional division of odor processing in both PN types.

  13. Odor supported place cell model and goal navigation in rodents

    DEFF Research Database (Denmark)

    Kulvicius, Tomas; Tamosiunaite, Minija; Ainge, James

    2008-01-01

    Experiments with rodents demonstrate that visual cues play an important role in the control of hippocampal place cells and spatial navigation. Nevertheless, rats may also rely on auditory, olfactory and somatosensory stimuli for orientation. It is also known that rats can track odors or self......-generated scent marks to find a food source. Here we model odor supported place cells by using a simple feed-forward network and analyze the impact of olfactory cues on place cell formation and spatial navigation. The obtained place cells are used to solve a goal navigation task by a novel mechanism based on self......-marking by odor patches combined with a Q-learning algorithm. We also analyze the impact of place cell remapping on goal directed behavior when switching between two environments. We emphasize the importance of olfactory cues in place cell formation and show that the utility of environmental and self...

  14. Do Masculine Men Smell Better? An Association Between Skin Color Masculinity and Female Preferences for Body Odor.

    Science.gov (United States)

    Carrito, Mariana L; Santos, Isabel M; Alho, Laura; Ferreira, Jacqueline; Soares, Sandra C; Bem-Haja, Pedro; Silva, Carlos F; Perrett, David I

    2017-03-01

    A recent study claimed face skin color as a sexually dimorphic variable that influences attractiveness preferences in mate choice. Thereby, skin color may assume the role of a mate quality signal influencing attractiveness preferences. As body odor is linked to attractiveness, this study aimed to explore whether the odors of men with more masculine facial skin color would be evaluated more positively than odors from less masculine men. Female raters were presented with body odors of 18 men and were asked to rate them in various characteristics. Multilevel modeling revealed that the odors of the donors with more masculine color were rated not only as more attractive, more pleasant, and sexier, but also healthier. This indicates that odor associated with men with more masculine skin color is attractive, just as other sexually dimorphic traits. Furthermore, we found a negative relation between skin color masculinity and perceived odor maleness. Regarding this last finding, a new discussion is introduced with respect to the influence of cognitive stereotypes in odor judgments. Altogether, the study supports the possibility that chemosensory signals may be communicating signs of mate quality associated with masculinity. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Male risk taking, female odors, and the role of estrogen receptors.

    Science.gov (United States)

    Kavaliers, Martin; Clipperton-Allen, Amy; Cragg, Cheryl L; Gustafsson, Jan-Åke; Korach, Kenneth S; Muglia, Louis; Choleris, Elena

    2012-12-05

    Male risk-taking and decision making are affected by sex-related cues, with men making riskier choices and decisions after exposure to either women or stimuli associated with women. In non-human species females and, or their cues can also increase male risk taking. Under the ecologically relevant condition of predation threat, brief exposure of male mice to the odors of a sexually receptive novel female reduces the avoidance of, and aversive responses to, a predator. We briefly review evidence showing that estrogen receptors (ERs), ERα and ERβ, are associated with the mediation of these risk taking responses. We show that ERs influence the production of the female odors that affect male risk taking, with the odors of wild type (ERαWT, ERβWT), oxytocin (OT) wildtype (OTWT), gene-deleted 'knock-out' ERβ (ERβKO), but not ERαKO or oxytocin (OT) OTKO or ovariectomized (OVX) female mice reducing the avoidance responses of male mice to cat odor. We further show that administration of specific ERα and ERβ agonists to OVX females results in their odors increasing male risk taking and boldness towards a predator. We also review evidence that ERs are involved in the mediation of the responses of males to female cues, with ERα being associated with the sexual and both ERβ and ERα with the sexual and social mechanisms underlying the effects of female cues on male risk taking. The implications and relations of these findings with rodents to ERs and the regulation of human risk taking are briefly considered. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. The Intensity of Human Body Odors and the MHC: Should We Expect a Link?

    OpenAIRE

    Claus Wedekind; Thomas Seebeck; Florence Bettens; Alexander J. Paepke

    2006-01-01

    It is now well established that genes within the major histocompatibility complex (MHC) somehow affect the production of body odors in several vertebrates, including humans. Here we discuss whether variation in the intensity of body odors may be influenced by the MHC. In order to examine this question, we have to control for MHC-linked odor perception on the smeller's side. Such a control is necessary because the perception of pleasantness and intensity seem to be confounded, a...

  17. Wildlife detection dog training: A case study on achieving generalization between target odor variations while retaining specificity

    NARCIS (Netherlands)

    Oldenburg, Cor; Schoon, Adee; Heitkönig, I.M.A.

    2016-01-01

    Wildlife detection dogs are required to correctly discriminate target wildlife species odor from nontarget
    species odors (specificity), while enabling some degree of target odor variation (generality). Because
    there is no standardized training protocol, and little knowledge on training

  18. Right Occipital Cortex Activation Correlates with Superior Odor Processing Performance in the Early Blind

    Science.gov (United States)

    Grandin, Cécile B.; Dricot, Laurence; Plaza, Paula; Lerens, Elodie; Rombaux, Philippe; De Volder, Anne G.

    2013-01-01

    Using functional magnetic resonance imaging (fMRI) in ten early blind humans, we found robust occipital activation during two odor-processing tasks (discrimination or categorization of fruit and flower odors), as well as during control auditory-verbal conditions (discrimination or categorization of fruit and flower names). We also found evidence for reorganization and specialization of the ventral part of the occipital cortex, with dissociation according to stimulus modality: the right fusiform gyrus was most activated during olfactory conditions while part of the left ventral lateral occipital complex showed a preference for auditory-verbal processing. Only little occipital activation was found in sighted subjects, but the same right-olfactory/left-auditory-verbal hemispheric lateralization was found overall in their brain. This difference between the groups was mirrored by superior performance of the blind in various odor-processing tasks. Moreover, the level of right fusiform gyrus activation during the olfactory conditions was highly correlated with individual scores in a variety of odor recognition tests, indicating that the additional occipital activation may play a functional role in odor processing. PMID:23967263

  19. A NOVEL CO2 SEPARATION SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Robert J. Copeland; Gokhan Alptekin; Mike Cesario; Steven Gebhard; Yevgenia Gershanovich

    1999-01-01

    Because of concern over global climate change, new systems are needed that produce electricity from fossil fuels and emit less CO{sub 2}. The fundamental problem with current CO{sub 2} separation systems is the need to separate dilute CO{sub 2} and pressurize it for storage or sequestration. This is an energy intensive process that can reduce plant efficiency by 9-37% and double the cost of electricity.

  20. Romantic love modulates women's identification of men's body odors.

    Science.gov (United States)

    Lundström, Johan N; Jones-Gotman, Marilyn

    2009-02-01

    Romantic love is one of our most potent and powerful emotions, but very little is known with respect to the hormonal and psychological mechanisms in play. Romantic love is thought to help intimate partners stay committed to each other and two mechanisms have been proposed to mediate this commitment: increased attention towards one's partner or deflected attention away from other potential partners. Both mechanisms find support in the literature. We explored the potential influence of each of these mechanisms by assessing women's ability to identify (ID) body odors originating from their boyfriend, a same-sex friend, and an opposite-sex friend and the relationship between this ability and the degree of romantic love expressed towards their boyfriend. We hypothesized that an increase in attention towards one's partner would render a positive correlation between ID of a boyfriend's body odor and degree of romantic love; conversely, we hypothesized that attention deflected away from other potential partners would render a negative correlation between ID of an opposite-sex friend's body odor and degree of romantic love for the boyfriend. Our results supported the deflection theory as we found a negative correlation between the degree of romantic love for the subjects' boyfriends and their ability to ID the body odor of an opposite-sex friend but not of their boyfriend or same-sex friend. Our results indicate that romantic love deflects attention away from potential new partners rather than towards the present partner. These changes are likely mediated by circulating neuropeptides and a testable model is suggested.

  1. Are single odorous components of a predator sufficient to elicit defensive behaviors in prey species?

    Directory of Open Access Journals (Sweden)

    Raimund eApfelbach

    2015-07-01

    Full Text Available When exposed to the odor of a sympatric predator, prey animals typically display escape or defensive responses. These phenomena have been well-documented, especially in rodents, when exposed to the odor of a cat, ferret or fox. As a result of these experiments new discussions center on the following questions: 1 is a single volatile compound such as a major or a minor mixture constituent in urine or feces, emitted by the predator sufficient to cause defensive reactions in a potential prey species or 2 is a whole array of odors required to elicit a response and 3 will the relative size or escapability of the prey as compared to the predator influence responsiveness. Most predator-prey studies on this topic have been performed in the laboratory or under semi-natural conditions. Field studies could help to find answers to these questions. Australian mammals are completely naïve towards the introduced placental carnivores. That offers ideal opportunities to analyze in the field the responses of potential prey species to unknown predator odors. During the last decades researchers have accumulated an enormous amount of data exploring the effects of eutherian predator odors on native marsupial mammals. In this review, we will give a survey about the development of olfactory research, chemical signals and their influence on the behavior and - in some cases - physiology of prey species. In addition, we report on the effects of predator odor experiments performed under natural conditions in Australia. When studying all these literature we learned that data gained under controlled laboratory conditions elucidate the role of individual odors on brain structures and ultimately on a comparatively narrow range behaviors. In contrast to single odors odor arrays mimic much more the situation prey animals are confronted to in nature. Therefore, a broad range of methodology — from chemistry to ecology including anatomy, physiology and behavior — is needed to

  2. Complementary and alternative therapies for management of odor in malignant fungating wounds: a critical review

    Directory of Open Access Journals (Sweden)

    Gethin G

    2016-06-01

    Full Text Available Georgina Gethin,1 Caroline McIntosh,2 Sebastian Probst3 1School of Nursing and Midwifery, National University of Ireland, Galway, 2Discipline of Podiatric Medicine, National University of Ireland, Galway, Ireland; 3School of Health, University of Applied Sciences Western Switzerland, Geneva, Switzerland Abstract: Malignant fungating wounds (MFWs affect an estimated 5%–10% of all people with cancer. They have a profound effect on the individual, and their associated symptoms such as bleeding, odor, exudate, and pain cause much distress, anxiety, and social isolation. Odor is cited by patients and clinicians as the worst aspect of such wounds. Strategies to manage odor at the wound site include the use of complementary and alternative therapies. This review aimed to synthesize the current evidence for the use of complementary and alternative therapies in the management of odor in MFWs. No restrictions on date, language, or care setting were applied. Nine databases were searched yielding four papers meeting our criteria. Of the four papers, one was a randomized controlled trial (RCT, and three were case studies. Two papers investigated the use of green tea teabags as a secondary dressing, while others used essential oils either combined with a cream applied directly to the wound or as a secondary dressing. In an RCT, green tea was used as a solution to cleanse the wound followed by the application of green tea teabag as a secondary dressing versus metronidazole powder for the management of odor over 7 days. All patients reported a reduction in odor and physical discomfort, and an improvement in social interaction and appetite, but the difference between groups was not statistically significant. The case studies all reported an improvement in odor management. The use of complementary and alternative therapies in the management of MFW-associated malodor is not supported by evidence from RCTs. Green tea may have potential as a secondary dressing to

  3. Are single odorous components of a predator sufficient to elicit defensive behaviors in prey species?

    Science.gov (United States)

    Apfelbach, Raimund; Parsons, Michael H; Soini, Helena A; Novotny, Milos V

    2015-01-01

    When exposed to the odor of a sympatric predator, prey animals typically display escape or defensive responses. These phenomena have been well-documented, especially in rodents, when exposed to the odor of a cat, ferret, or fox. As a result of these experiments new discussions center on the following questions: (1) is a single volatile compound such as a major or a minor mixture constituent in urine or feces, emitted by the predator sufficient to cause defensive reactions in a potential prey species or (2) is a whole array of odors required to elicit a response and (3) will the relative size or escapability of the prey as compared to the predator influence responsiveness. Most predator-prey studies on this topic have been performed in the laboratory or under semi-natural conditions. Field studies could help to find answers to these questions. Australian mammals are completely naïve toward the introduced placental carnivores. That offers ideal opportunities to analyze in the field the responses of potential prey species to unknown predator odors. During the last decades researchers have accumulated an enormous amount of data exploring the effects of eutherian predator odors on native marsupial mammals. In this review, we will give a survey about the development of olfactory research, chemical signals and their influence on the behavior and-in some cases-physiology of prey species. In addition, we report on the effects of predator odor experiments performed under natural conditions in Australia. When studying all these literature we learned that data gained under controlled laboratory conditions elucidate the role of individual odors on brain structures and ultimately on a comparatively narrow range behaviors. In contrast to single odors odor arrays mimic much more the situation prey animals are confronted to in nature. Therefore, a broad range of methodology-from chemistry to ecology including anatomy, physiology, and behavior-is needed to understand all the

  4. Electroencephalographic Response to Different Odors in Healthy Individuals: A Promising Tool for Objective Assessment of Olfactory Disorders.

    Science.gov (United States)

    Krbot Skorić, Magdalena; Adamec, Ivan; Jerbić, Ana Branka; Gabelić, Tereza; Hajnšek, Sanja; Habek, Mario

    2015-10-01

    The aim of the present study was to examine human central nervous system response to three different odors. Electrophysiological activity was recorded in the baseline state and for 3 odors, lemon, peppermint, and vanilla, in 16 healthy participants. Electrodes were separated into groups according to the spatial position on the head. Fast Fourier transformation was performed on every set, and mean value of activity in theta was exported. As theta showed statistically significant results, further analysis was based only on the theta frequency band. On electrodes FP1, F3, Fz, F4, F8, T7, C3, Cz, C4, T8, TP9, CP5, CP1, CP2, CP6, P7, P3, Pz, P4, P8, PO9, and PO10 there was statistically significant difference in the electrical activity of the brain between four conditions. For peppermint and lemon, there was statistically significant difference in activity between different regions-F(1.576, 23.637)=16.030, P=.000 and F(1.362, 20.425)=4.54, P=.035, respectively-where the activity in the central area was significantly reduced compared with the activity in the other 4 areas and in the left and right anterior and left posterior area, respectively. There was no statistically significant difference for vanilla between specific areas, F(1.217, 18.257)=1.155, P=.309. The results indicate that olfactory stimuli can affect the frequency characteristics of the electrical activity of the brain. © EEG and Clinical Neuroscience Society (ECNS) 2014.

  5. Contribution of DA Signaling to Appetitive Odor Perception in a Drosophila Model.

    Science.gov (United States)

    Pu, Yuhan; Palombo, Melissa Megan Masserant; Shen, Ping

    2018-04-13

    Understanding cognitive processes that translate chemically diverse olfactory stimuli to specific appetitive drives remains challenging. We have shown that food-related odors arouse impulsive-like feeding of food media that are palatable and readily accessible in well-nourished Drosophila larvae. Here we provide evidence that two assemblies of four dopamine (DA) neurons, one per brain hemisphere, contribute to perceptual processing of the qualitative and quantitative attributes of food scents. These DA neurons receive neural representations of chemically diverse food-related odors, and their combined neuronal activities become increasingly important as the chemical complexity of an appetizing odor stimulus increases. Furthermore, in each assembly of DA neurons, integrated odor signals are transformed to one-dimensional DA outputs that have no intrinsic reward values. Finally, a genetic analysis has revealed a D1-type DA receptor (Dop1R1)-gated mechanism in neuropeptide Y-like neurons that assigns appetitive significance to selected DA outputs. Our findings suggest that fly larvae provide a useful platform for elucidation of molecular and circuit mechanisms underlying cognitive processing of olfactory and possibly other sensory cues.

  6. Chemical composition of axillary odorants reflects social and individual attributes in rhesus macaques.

    Science.gov (United States)

    Weiß, Brigitte M; Kücklich, Marlen; Thomsen, Ruth; Henkel, Stefanie; Jänig, Susann; Kulik, Lars; Birkemeyer, Claudia; Widdig, Anja

    2018-01-01

    Scents play an important role in the life of most terrestrial mammals and may transmit valuable information about conspecifics. Olfaction was long considered of low importance in Old World monkeys due to their relative reduction of olfactory structures and low incidence of scent-marking behavior but has been increasingly recognized for mediating social relationships in recent years. Yet, studies investigating the composition of their chemical cues remain scarce. In the present study, we analyzed the potential information content of chemicals present on the skin of rhesus macaques ( Macaca mulatta ). We collected axillary secretions from 60 animals of the semifree-ranging population on Cayo Santiago (Puerto Rico, USA) with precleaned cotton swabs from which the secretions were subsequently extracted and analyzed by gas chromatography-mass spectrometry. Rhesus macaque axillary odorants varied in their overall similarity and composition. This variation was attributable to differences in sex, group membership, and kinship and further appeared to reflect age and rank in parts of our sample. The compounds most strongly associated with this variation primarily comprised larger molecular weight aldehydes and steroids. Such compounds are considered to be perceivable by the primate olfactory system through close-range interactions or through breakdown into smaller molecules by bacterial fermentation. Overall, our results provide additional evidence that odors of Old World monkeys reflect a wealth of potential information about their carrier, which provides the basis for chemical communication via body odors; however, its use by conspecifics needs to be confirmed in bioassays. One prerequisite for olfactory communication is the presence of systematic variation in animal odors that is related to attributes such as age, sex, or kinship. The composition of odors has been examined in numerous mammals but, with the exception of humans, remains poorly understood in Old World

  7. Analysis of odorant receptor protein function in the yellow fever mosquito, aedes aegypti

    Science.gov (United States)

    Odorant receptors (ORs) in insects are ligand-gated ion channels comprised of two subunits: a variable receptor and an obligatory co-receptor (Orco). This protein receptor complex of unknown stoichiometry interacts with an odor molecule leading to changes in permeability of the sensory dendrite, th...

  8. The CEBAF RF separator system

    International Nuclear Information System (INIS)

    Hovater, C.; Arnold, G.; Fugitt, J.; Harwood, L.; Kazimi, R.; Lahti, G.; Mammosser, J.; Nelson, R.; Piller, C.; Turlington, L.

    1996-01-01

    The 4 GeV CEBAF accelerator at Thomas Jefferson National Accelerator Facility (Jefferson Lab) is arranged in a five-pass racetrack configuration, with two superconducting radio-frequency (SRF) linacs joined by independent magnetic transport arcs. The 1497 MHz continuous electron beam is composed of three interlaced variable-intensity 499 MHz beams that can be independently directed from any of the five passes to any of the three experimental halls. Beam extraction is made possible by a system of nine warm sub-harmonic separator cavities capable of delivering a 100 urad kick to any pass at a maximum machine energy of 6 GeV. Each separator cavity is a half-wavelength, two cell design with a high transverse shunt impedance and a small transverse dimension. The cavities are powered by 1 kW solid state amplifiers operating at 499 MHz. Cavity phase and gradient control are provided through a modified version of the same control module used for the CEBAF SRF cavity controls. The system has recently been tested while delivering beam to Hall C. In this paper we present a description of the RF separator system and recent test results with beam. (author)

  9. Long-term odor recognition memory in unipolar major depression and Alzheimer׳s disease.

    Science.gov (United States)

    Naudin, Marine; Mondon, Karl; El-Hage, Wissam; Desmidt, Thomas; Jaafari, Nematollah; Belzung, Catherine; Gaillard, Philippe; Hommet, Caroline; Atanasova, Boriana

    2014-12-30

    Major depression and Alzheimer׳s disease (AD) are often observed in the elderly. The identification of specific markers for these diseases could improve their screening. The aim of this study was to investigate long-term odor recognition memory in depressed and AD patients, with a view to identifying olfactory markers of these diseases. We included 20 patients with unipolar major depressive episodes (MDE), 20 patients with mild to moderate AD and 24 healthy subjects. We investigated the cognitive profile and olfactory memory capacities (ability to recognize familiar and unfamiliar odors) of these subjects. Olfactory memory test results showed that AD and depressed patients were characterized by significantly less correct responses and more wrong responses than healthy controls. Detection index did not differ significantly between patients with major depression and those with AD when the results were analyzed for all odors. However, MDE patients displayed an impairment of olfactory memory for both familiar and unfamiliar odors, whereas AD subjects were impaired only in the recognition of unfamiliar odors, with respect to healthy subjects. If preservation of olfactory memory for familiar stimuli in patients with mild to moderate AD is confirmed, this test could be used in clinical practice as a complementary tool for diagnosis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. Maternal programming of sex-specific responses to predator odor stress in adult rats.

    Science.gov (United States)

    St-Cyr, Sophie; Abuaish, Sameera; Sivanathan, Shathveekan; McGowan, Patrick O

    2017-08-01

    Prenatal stress mediated through the mother can lead to long-term adaptations in stress-related phenotypes in offspring. This study tested the long-lasting effect of prenatal exposure to predator odor, an ethologically relevant and psychogenic stressor, in the second half of pregnancy. As adults, the offspring of predator odor-exposed mothers showed increased anxiety-like behaviors in commonly used laboratory tasks assessing novelty-induced anxiety, increased defensive behavior in males and increased ACTH stress reactivity in females in response to predator odor. Female offspring from predator odor-exposed dams showed increased transcript abundance of glucocorticoid receptor (NR3C1) on the day of birth and FK506 binding protein 5 (FKBP5) in adulthood in the amygdala. The increase in FKBP5 expression was associated with decreased DNA methylation in Fkbp5 intron V. These results indicate a sex-specific response to maternal programming by prenatal predator odor exposure and a potential epigenetic mechanism linking these responses with modifications of the stress axis in females. These results are in accordance with the mismatch hypothesis stating that an animal's response to cues within its life history reflects environmental conditions anticipated during important developmental periods and should be adaptive when these conditions are concurring. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Effects of odors on behaviors of captive Amur leopards Panthera pardus orientalis

    Directory of Open Access Journals (Sweden)

    Shangying YU

    2009-02-01

    Full Text Available Captive environments often fail to resemble the wild environment in respects of limited space, unchanging habitat, lack of stimulus and contingency. Common animal welfare problems which occur in captive animals include low behavioral diversity, abnormal behavior and excessive inactivity. Environmental enrichment, as an effective strategy to tackle these problems and promote mental health of captive animals, has been recognized as an important principal for captive animal management. Among all the enrichment techniques, olfactory enrichment is a simple and effective method for improving the well-being of the olfactory sensitive felids. Behavioral problems were observed in six Amur leopards Panthera pardus orientalis at Beijing Zoological Garden. These were held in the older type exhibits which have now been rebuilt. These behaviors include stereotypic behavior and excessive inactivity caused by the spatially limited enclosures with low levels of stimuli. To determine the effects of predator, prey, and herb odors as potential enrichment materials for captive leopards, we conducted olfactory enrichment experiments for the leopards and tested the effects of nutmeg Myristica fragrans, feces of roe deer Capreolus capreolus and urine of Amur tiger Panthera tigris altaica to test for an increase in behavioral repertoire and activity. Odors provided in this study were also believed to improve the psychological and physiological health of individuals. To standardize the method of presentation the odors were introduced to the enclosures by rubbing or spraying onto a clean towel. Our results show that the selected three odors effectively increased the behavioral diversity. Ten new behavior types were observed in the nutmeg experiment, eight in the feces of roe deer experiment and six in the tiger urine experiment. Among the three odors, cats responded to nutmeg for the longest duration, followed by tiger urine and feces of roe deer. Leopards showed more

  12. Environmental Effects Exceed Genetic Effects on Perceived Intensity and Pleasantness of Several Odors

    DEFF Research Database (Denmark)

    Knaapila, Antti; Tuorila, Hely; Silventoinen, Karri

    2008-01-01

    and pleasantness of cinnamon, chocolate, turpentine, and isovaleric acid (sweaty) odors by quantitative genetic modeling of odor rating data from 856 twin individuals (including 83 complete monozygotic and 275 dizygotic twin pairs) aged 10-60 years (44% males and 56% females) from Australia, Denmark, and Finland...

  13. Infant rats can learn time intervals before the maturation of the striatum: evidence from odor fear conditioning

    Directory of Open Access Journals (Sweden)

    Julie eBoulanger Bertolus

    2014-05-01

    Full Text Available Interval timing refers to the ability to perceive, estimate and discriminate durations in the range of seconds to minutes. Very little is currently known about the ontogeny of interval timing throughout development. On the other hand, even though the neural circuit sustaining interval timing is a matter of debate, the striatum has been suggested to be an important component of the system and its maturation occurs around the third post-natal week in rats. The global aim of the present study was to investigate interval timing abilities at an age for which striatum is not yet mature. We used odor fear conditioning, as it can be applied to very young animals. In odor fear conditioning, an odor is presented to the animal and a mild footshock is delivered after a fixed interval. Adult rats have been shown to learn the temporal relationships between the odor and the shock after a few associations. The first aim of the present study was to assess the activity of the striatum during odor fear conditioning using 2-Deoxyglucose autoradiography during development in rats. The data showed that although fear learning was displayed at all tested ages, activation of the striatum was observed in adults but not in juvenile animals. Next, we assessed the presence of evidence of interval timing in ages before and after the inclusion of the striatum into the fear conditioning circuit. We used an experimental setup allowing the simultaneous recording of freezing and respiration that have been demonstrated to be sensitive to interval timing in adult rats. This enabled the detection of duration-related temporal patterns for freezing and/or respiration curves in infants as young as 12 days post-natal during odor-fear conditioning. This suggests that infants are able to encode time durations as well as and as quickly as adults while their striatum is not yet functional. Alternative networks possibly sustaining interval timing in infant rats are discussed.

  14. Olfactory reference syndrome: demographic and clinical features of imagined body odor.

    Science.gov (United States)

    Phillips, Katharine A; Menard, William

    2011-01-01

    Olfactory reference syndrome (ORS) - preoccupation with a false belief that one emits a foul or offensive body odor - has been described around the world for more than a century. However, only a few small studies have systematically assessed ORS's clinical features. Twenty patients with ORS were systematically assessed using semistructured measures. Subjects' mean age was 33.4±14.1; 60% were female. Preoccupation most often focused on the mouth (75%), armpits (60%) and genitals (35%). Bad breath (75%) and sweat (65%) were the most common odor descriptions. Currently, 85% of subjects had delusional ORS beliefs, 77% had referential thinking and 85% reported actually smelling the odor. Ninety-five percent of subjects reported performing one or more ORS-related repetitive behaviors (e.g., excessive showering). Forty percent had been housebound for at least 1 week because of ORS symptoms, 68% had a history of suicidal ideation, 32% had attempted suicide and 53% had been psychiatrically hospitalized. Forty-four percent of subjects had sought nonpsychiatric medical, surgical or dental treatment for the perceived odor, and one third had received such treatment, which was ineffective in all cases. ORS appears to be characterized by high morbidity and seeking of nonpsychiatric treatment. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Odorants could elicit repair processes in melanized neuronal and skin cells

    Directory of Open Access Journals (Sweden)

    Barbara Pavan

    2017-01-01

    Full Text Available The expression of ectopic olfactory receptors (ORs in melanized cells, such as the human brain nigrostriatal dopaminergic neurons and skin melanocytes, is here pointed out. ORs are recognized to regulate skin melanogenesis, whereas OR expression in the dopaminergic neurons, characterized by accumulation of pigment neuromelanin, is downregulated in Parkinson's disease. Furthermore, the correlation between the pigmentation process and the dopamine pathway through α-synuclein expression is also highlighted. Purposely, these ORs are suggested as therapeutic target for neurodegenerative diseases related to the pigmentation disorders. Based on this evidence, a possible way of turning odorants into drugs, acting on three specific olfactory receptors, OR51E2, OR2AT4 and VN1R1, is thus introduced. Various odorous molecules are shown to interact with these ORs and their therapeutic potential against melanogenic and neurodegenerative dysfunctions, including melanoma and Parkinson's disease, is suggested. Finally, a direct functional link between olfactory and endocrine systems in human brain through VN1R1 is proposed, helping to counteract female susceptibility to Parkinson's disease in quiescent life.

  16. Sensing of Scent, Fragrance, Smell, and Odor Emissions from Biota Sources

    Directory of Open Access Journals (Sweden)

    Ki-Hyun Kim

    2014-04-01

    Full Text Available People encounter enormous numbers of chemicals present in the outdoor atmosphere and/or in the various facilities they use daily. Despite such diversity, not many of them have necessarily the potential to draw human’s nasal attraction if their perception thresholds are in general not sufficiently low enough, regardless of abundance. In this sense, many types of scents, musks, fragrances, smells, odors, and pheromones are unique enough to draw a great deal of attention mainly by their presence at or near threshold levels which are far lower than those of common chemicals with poor odorant characteristics. It is known that most of the diverse characters of odor-related ingredients or expressions are commonly produced from various biota sources present in the biosphere, e.g., fauna, flora, bacteria, fruits, flowers, trees, meats, fresh/decaying foods, etc.

  17. Hydrodynamic Interactions Between Olfactory Appendages and Odor Plumes

    National Research Council Canada - National Science Library

    Koseff, Jeffrey

    2000-01-01

    .... A model lobster was then placed in the laboratory flume and we measured the odor concentration distribution around the olfactory appendage using high-speed video and laser-induced fluorescence techniques...

  18. Effect of Dietary Protein Levels on Composition of Odorous Compounds and Bacterial Ecology in Pig Manure

    Directory of Open Access Journals (Sweden)

    Sungback Cho

    2015-09-01

    Full Text Available This study was performed to investigate the effect of different levels of dietary crude protein (CP on composition of odorous compounds and bacterial communities in pig manure. A total of 48 male pigs (average initial body weight 45 kg fed diets containing three levels of dietary CP (20%, 17.5%, and 15% and their slurry samples were collected from the pits under the floor every week for one month. Changes in composition of odorous compounds and bacterial communities were analyzed by gas chromatography and 454 FLX titanium pyrosequencing systems, respectively. Levels of phenols, indoles, short chain fatty acid and branched chain fatty acid were lowest (p<0.05 in CP 15% group among three CP levels. Relative abundance of Bacteroidetes phylum and bacterial genera including Leuconostoc, Bacillus, Atopostipes, Peptonphilus, Ruminococcaceae_uc, Bacteroides, and Pseudomonas was lower (p<0.05 in CP 15% than in CP 20% group. There was a positive correlation (p<0.05 between odorous compounds and bacterial genera: phenol, indole, iso-butyric acid, and iso-valeric acid with Atopostipes, p-cresol and skatole with Bacteroides, acetic acid and butyric acid with AM982595_g of Porphyromonadaceae family, and propionic acid with Tissierella. Taken together, administration of 15% CP showed less production of odorous compounds than 20% CP group and this result might be associated with the changes in bacterial communities especially whose roles in protein metabolism.

  19. Recognition memory for social and non-social odors: differential effects of neurotoxic lesions to the hippocampus and perirhinal cortex.

    Science.gov (United States)

    Feinberg, Leila M; Allen, Timothy A; Ly, Denise; Fortin, Norbert J

    2012-01-01

    The contributions of the hippocampus (HC) and perirhinal cortex (PER) to recognition memory are currently topics of debate in neuroscience. Here we used a rapidly-learned (seconds) spontaneous novel odor recognition paradigm to assess the effects of pre-training N-methyl-D-aspartate lesions to the HC or PER on odor recognition memory. We tested memory for both social and non-social odor stimuli. Social odors were acquired from conspecifics, while non-social odors were household spices. Conspecific odor stimuli are ethologically-relevant and have a high degree of overlapping features compared to non-social household spices. Various retention intervals (5 min, 20 min, 1h, 24h, or 48 h) were used between study and test phases, each with a unique odor pair, to assess changes in novelty preference over time. Consistent with findings in other paradigms, modalities, and species, we found that HC lesions yielded no significant recognition memory deficits. In contrast, PER lesions caused significant deficits for social odor recognition memory at long retention intervals, demonstrating a critical role for PER in long-term memory for social odors. PER lesions had no effect on memory for non-social odors. The results are consistent with a general role for PER in long-term recognition memory for stimuli that have a high degree of overlapping features, which must be distinguished by conjunctive representations. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. An odor-specific threshold deficit implicates abnormal cAMP signaling in youths at clinical risk for psychosis.

    Science.gov (United States)

    Kamath, Vidyulata; Moberg, Paul J; Calkins, Monica E; Borgmann-Winter, Karin; Conroy, Catherine G; Gur, Raquel E; Kohler, Christian G; Turetsky, Bruce I

    2012-07-01

    While olfactory deficits have been reported in schizophrenia and youths at-risk for psychosis, few studies have linked these deficits to current pathophysiological models of the illness. There is evidence that disrupted cyclic adenosine 3',5'-monophosphate (cAMP) signaling may contribute to schizophrenia pathology. As cAMP mediates olfactory signal transduction, the degree to which this disruption could manifest in olfactory impairment was ascertained. Odor-detection thresholds to two odorants that differ in the degree to which they activate intracellular cAMP were assessed in clinical risk and low-risk participants. Birhinal assessments of odor-detection threshold sensitivity to lyral and citralva were acquired in youths experiencing prodromal symptoms (n=17) and controls at low risk for developing psychosis (n=15). Citralva and lyral are odorants that differ in cAMP activation; citralva is a strong cAMP activator and lyral is a weak cAMP activator. The overall group-by-odor interaction was statistically significant. At-risk youths showed significantly reduced odor detection thresholds for lyral, but showed intact detection thresholds for citralva. This odor-specific threshold deficit was uncorrelated with deficits in odor identification or discrimination, which were also present. ROC curve analysis revealed that olfactory performance correctly classified at-risk and low-risk youths with greater than 97% accuracy. This study extends prior findings of an odor-specific hyposmia implicating cAMP-mediated signal transduction in schizophrenia and unaffected first-degree relatives to include youths at clinical risk for developing the disorder. These results suggest that dysregulation of cAMP signaling may be present during the psychosis prodrome. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Intraspecific preen oil odor preferences in dark-eyed juncos (Junco hyemalis)

    OpenAIRE

    Danielle J. Whittaker; Kaitlin M. Richmond; Allison K. Miller; Ryan Kiley; Christine Bergeon Burns; Jonathan W. Atwell; Ellen D. Ketterson

    2011-01-01

    Most birds possess a uropygial gland that produces a secretion, preen oil, that contains volatile compounds that may transmit information about individual attributes. However, the ability of passerine songbirds to discriminate among the odors of different individuals has not yet been demonstrated. We tested whether dark-eyed juncos (Junco hyemalis) could discriminate among preen oil odors from 1) conspecifics and heterospecifics; 2) male and female conspecifics; 3) conspecifics from same or d...

  2. Odor-based recognition of familiar and related conspecifics: a first test conducted on captive Humboldt penguins (Spheniscus humboldti.

    Directory of Open Access Journals (Sweden)

    Heather R Coffin

    Full Text Available Studies of kin recognition in birds have largely focused on parent-offspring recognition using auditory or visual discrimination. Recent studies indicate that birds use odors during social and familial interactions and possibly for mate choice, suggesting olfactory cues may mediate kin recognition as well. Here, we show that Humboldt penguins (Spheniscus humboldti, a natally philopatric species with lifetime monogamy, discriminate between familiar and unfamiliar non-kin odors (using prior association and between unfamiliar kin and non-kin odors (using phenotype matching. Penguins preferred familiar non-kin odors, which may be associated with the recognition of nest mates and colony mates and with locating burrows at night after foraging. In tests of kin recognition, penguins preferred unfamiliar non-kin odors. Penguins may have perceived non-kin odors as novel because they did not match the birds' recognition templates. Phenotype matching is likely the primary mechanism for kin recognition within the colony to avoid inbreeding. To our knowledge this is the first study to provide evidence of odor-based kin discrimination in a bird.

  3. Odors and sensations of humidity and dryness in relation to sick building syndrome and home environment in Chongqing, China.

    Directory of Open Access Journals (Sweden)

    Juan Wang

    Full Text Available The prevalence of perceptions of odors and sensations of air humidity and sick building syndrome symptoms in domestic environments were studied using responses to a questionnaire on the home environment. Parents of 4530 1-8 year old children from randomly selected kindergartens in Chongqing, China participated. Stuffy odor, unpleasant odor, pungent odor, mold odor, tobacco smoke odor, humid air and dry air in the last three month (weekly or sometimes was reported by 31.4%, 26.5%, 16.1%, 10.6%, 33.0%, 32.1% and 37.2% of the parents, respectively. The prevalence of parents' SBS symptoms (weekly or sometimes were: 78.7% for general symptoms, 74.3% for mucosal symptoms and 47.5% for skin symptoms. Multi-nominal regression analyses for associations between odors/sensations of air humidity and SBS symptoms showed that the odds ratio for "weekly" SBS symptoms were consistently higher than for "sometimes" SBS symptoms. Living near a main road or highway, redecoration, and new furniture were risk factors for perceptions of odors and sensations of humid air and dry air. Dampness related problems (mold spots, damp stains, water damage and condensation were all risk factors for perceptions of odors and sensations of humid air and dry air, as was the presence of cockroaches, rats, and mosquitoes/flies, use of mosquito-repellent incense and incense. Protective factors included cleaning the child's bedroom every day and frequently exposing bedding to sunshine. In conclusion, adults' perceptions of odors and sensations of humid air and dry air are related to factors of the home environment and SBS symptoms are related to odor perceptions.

  4. A new submarine oil-water separation system

    Science.gov (United States)

    Cai, Wen-Bin; Liu, Bo-Hong

    2017-12-01

    In order to solve the oil field losses of environmental problems and economic benefit caused by the separation of lifting production liquid to offshore platforms in the current offshore oil production, from the most basic separation principle, a new oil-water separation system has been processed of adsorption and desorption on related materials, achieving high efficiency and separation of oil and water phases. And the submarine oil-water separation device has been designed. The main structure of the device consists of gas-solid phase separation device, period separating device and adsorption device that completed high efficiency separation of oil, gas and water under the adsorption and desorption principle, and the processing capacity of the device is calculated.

  5. Avaliação de impactos de odores em bacias hidrográficas com produções de suínos Evaluation of odor impacts in hydrographic basins with swine production

    Directory of Open Access Journals (Sweden)

    Paulo Belli Filho

    2007-09-01

    Full Text Available A bacia hidrográfica de Rio Fragosos, no oeste catarinense e a bacia hidrográfica do Rio Cachoeirinhas, no sul de Santa Catarina foram unidades pilotos para a aplicação de duas metodologias para avaliações de odores provenientes da suinocultura. Na bacia do Rio Fragosos ficou destacado para a grande maioria das pessoas situações de ambiente desagradável, muito desagradável e extremamente desagradável. As concentrações dos odores obtidos na bacia do Rio Cachoeirinhas, determinadas a montante e a jusante de uma propriedade piloto, no interior de uma granja de criação de animais, sobre uma unidade de armazenamento de seus dejetos e na residência de um produtor variaram de 257 UO/m³à 963 UO/m³. Estas concentrações indicaram intensidades de odores com níveis forte a muito forte.The River Fragosos hydrographic basin in the west of Santa Catarina and the River Cachoeirinhas hydrographic basin in the south of Santa Catarina were the pilot units for the application of two methodologies for the evaluation of odors originating from swine rearing. In From the results obtained for the River Fragosos basin, for the great majority of responses, unpleasant, very unpleasant and extremely unpleasant environmental situations were highlighted. The odor concentrations obtained for the River Cachoeirinhas basin, determined upstream and downstream of a pilot property, inside animal rearing smallholdings, above a waste storage unit and a producer's home, varied from 257 OU/m³to 963 OU/m³. These concentrations indicate odor intensities with strong and very strong levels.

  6. Odorant Normative Data for Use in Olfactory Memory Experiments: Dimension Selection and Analysis of Individual Differences.

    Science.gov (United States)

    Moss, Andrew G; Miles, Christopher; Elsley, Jane V; Johnson, Andrew J

    2016-01-01

    The present study reports normative ratings for 200 food and non-food odors. One hundred participants rated odors across measures of verbalisability, perceived descriptive ability, context availability, pleasantness, irritability, intensity, familiarity, frequency, age of acquisition, and complexity. Analysis of the agreement between raters revealed that four dimensions, those of familiarity, intensity, pleasantness, and irritability, have the strongest utility as normative data. The ratings for the remaining dimensions exhibited reduced discriminability across the odor set and should therefore be used with caution. Indeed, these dimensions showed a larger difference between individuals in the ratings of the odors. Familiarity was shown to be related to pleasantness, and a non-linear relationship between pleasantness and intensity was observed which reflects greater intensity for odors that elicit a strong hedonic response. The suitability of these data for use in future olfactory study is considered, and effective implementation of the data for controlling stimuli is discussed.

  7. Development of a ventilation system to remove odors and dust in a large indoor space; Daikukan no shuki funjin jokyo kanki system no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kadoya, M.; Moteki, M.; Tatsumi, T.; Enokida, D.; Miyagi, H.; Maruoka, T. [Okumura Corp., Osaka (Japan)

    1997-07-31

    The ventilation system for removing odor and dust was studied for the waste stock yard and working yard of a segregated waste stock facility of 17,280m{sup 3} in air volume. The developed ventilation system includes the air curtain and wind shield plate between the waste stock yard and working yard. Air curtain flow is formed by jet stream from nozzles installed at certain constant intervals. This system was developed through air flow analysis, model experiment, and field measurement. The air flow analysis pointed out that reverse flow derived from a part of air flow contaminates the working yard, however, this system can exclude such reverse flow and reduce CO2 concentration to 1/80. The model experiment result showed that this system can reduce CO2 concentration to 1/18. The field measurement confirmed the air curtain effect by smoke visualization. In the measurement of dummy dust concentration generated for 15min, this system was possible to reduce the concentration to 1/7. 4 refs., 18 figs., 6 tabs.

  8. Radioactive substance separation systems

    International Nuclear Information System (INIS)

    Sakai, Takuhiko.

    1981-01-01

    Purpose: To enable separation of fission products, radioactive corrosion products and the likes in primary coolants with no requirement for the replacement of separation system during plant service life, by providing protruded magnetic pole plates in a liquid metal flow channel to thereby form slopes magnetic fields. Constitution: A plurality of magnetic pole plates are disposed vertically in a comb-like arrangement so as not to contact with each other along the direction of flow in a rectangular primary coolant pipeway at the exit of the reactor core in an LMFBR type reactor. Large magnetic poles are provided to the upper and lower sides of the pipeway and coils are wound on the side opposed to the pipeway. When electrical current is supplied to the coils, the magnetic pole is magnetized intensely and thus the magnetic pole plates are also magnetized intensely and thus the magnetic pole plates are also magnetized intensely to form large gradient in the magnetic fields between the upper and lower magnetic plates, whereby ferromagnetic and ferrimagnetic fission products and radioactive corrosion products in the coolants are intensely adsorbed and not detached by the flow of the coolants. Accordingly, the fission products and the radioactive corrosion products can surely be removed with no requirement for the exchange of separation system during plant service life. (Horiuchi, T.)

  9. Influence of conspecific and heterospecific aggregation cues and alarm odors on shelter choice by syntopic spiny lobsters.

    Science.gov (United States)

    Briones-Fourzán, Patricia; Ramírez-Zaldívar, Eunice; Lozano-Alvarez, Enrique

    2008-10-01

    In spiny lobsters, conspecific scents ("aggregation cues") may mediate gregarious diurnal sheltering, but scents from injured conspecifics ("alarm odors") may elicit avoidance behavior. In laboratory experiments, individuals of two coexisting species, Panulirus guttatus (a reef-obligate) and P. argus (a temporary reef-dweller), significantly chose shelters emanating conspecific aggregation cues and responded randomly to shelters emanating heterospecific aggregation cues. However, despite evidence that the two species perceived each other's alarm odors to a similar extent, P. guttatus responded randomly to shelters emanating either conspecific or heterospecific alarm odors, whereas P. argus significantly avoided both. This differential influence of alarm odors likely reflects interspecific differences in life history, sociality, and behavior. The less social, reef-obligate P. guttatus lobsters forage close to their reef dens, into which they retract deeply upon perception of risk. This cryptic behavior may offset the need to avoid conspecific (and heterospecific) alarm odors. In contrast, avoidance of conspecific alarm odors by P. argus is consistent with its ontogenetic habitat shifts and greater sociality. Furthermore, because reef-dwelling P. argus lobsters forage across open areas away from the reef, an ability to avoid alarm odors from P. guttatus upon returning to their reef dens may increase their fitness.

  10. Quantification and sensory studies of character impact odorants of different soybean lecithins.

    Science.gov (United States)

    Stephan, A; Steinhart, H

    1999-10-01

    Fifty-four potent odorants in standardized, hydrolyzed, and deoiled and hydrolyzed soybean lecithins were quantified by high-resolution gas chromatography/mass spectrometry (HRGC/MS). The characterization of their aroma impact was performed by calculation of nasal (n) and retronasal (r) odor activity values (OAVs). For this, the nasal and retronasal recognition thresholds of 18 odor-active compounds were determined in vegetable oil. The following compounds showed the highest nOAVs: 2,3-diethyl-5-methylpyrazine, methylpropanal, acetic acid, pentanoic acid, 2-ethyl-3,5-dimethylpyrazine, pentylpyridine, (Z)-1,5-octadien-3-one, 2-methylbutanal, and beta-damascenone. In addition to the compounds above, 1-octen-3-one, 1-nonen-3-one, and 3-methyl-2,4-nonandione showed potent rOAVs. The results of quantification and OAV calculation were confirmed by a model mixture of 25 impact odorants, which yielded a highly similar sensory profile to that of the original soybean lecithin. The sensory importance of pyrazines and free acids increased through enzymatic hydrolysis and decreased by the process of deoiling. The impact of unsaturated ketones on the lecithin aroma was not changed by either process.

  11. Effect of experience with pine (Pituophis melanoleucus) and king (Lampropeltis getulus) snake odors on Y-maze behavior of pine snake hatchlings.

    Science.gov (United States)

    Burger, J; Boarman, W; Kurzava, L; Gochfeld, M

    1991-01-01

    The abilities of hatchling pine snakes (Pituophis melanoleucus) and king snakes (Lampropeltis getulus) to discriminate the chemical trails of pine and king snakes was investigated inY-maze experiments. Pine snakes were housed for 17 days either with shavings impregnated with pine snake odor, king snake odor, or no odor to test for the effect of experience on choice. Both pine and king snake hatchlings entered the arm with the pine snake odor and did not enter the arm with the king snake odor. The data support the hypothesis that hatchlings of both species can distinguish conspecific odors from other odors and that our manipulation of previous experience was without effect for pine snake hatchlings.

  12. Olfactory LOVER: Behavioral and neural correlates of autobiographical odor memory

    Directory of Open Access Journals (Sweden)

    Maria eLarsson

    2014-04-01

    Full Text Available Autobiographical memories (AMs are personally experienced events that may be localized in time and space. In the present work we present an overview targeting memories evoked by the sense of smell. Overall, research indicates that autobiographical odor memory is different than memories evoked by our primary sensory systems; sight and hearing. Here, observed differences from a behavioral and neuroanatomical perspective are presented. The key features of an olfactory evoked AM may be referred to the LOVER acronym - Limbic, Old, Vivid, Emotional, and Rare.

  13. Printed Spacecraft Separation System

    Energy Technology Data Exchange (ETDEWEB)

    Dehoff, Ryan R [ORNL; Holmans, Walter [Planetary Systems Corporation

    2016-10-01

    In this project Planetary Systems Corporation proposed utilizing additive manufacturing (3D printing) to manufacture a titanium spacecraft separation system for commercial and US government customers to realize a 90% reduction in the cost and energy. These savings were demonstrated via “printing-in” many of the parts and sub-assemblies into one part, thus greatly reducing the labor associated with design, procurement, assembly and calibration of mechanisms. Planetary Systems Corporation redesigned several of the components of the separation system based on additive manufacturing principles including geometric flexibility and the ability to fabricate complex designs, ability to combine multiple parts of an assembly into a single component, and the ability to optimize design for specific mechanical property targets. Shock absorption was specifically targeted and requirements were established to attenuate damage to the Lightband system from shock of initiation. Planetary Systems Corporation redesigned components based on these requirements and sent the designs to Oak Ridge National Laboratory to be printed. ORNL printed the parts using the Arcam electron beam melting technology based on the desire for the parts to be fabricated from Ti-6Al-4V based on the weight and mechanical performance of the material. A second set of components was fabricated from stainless steel material on the Renishaw laser powder bed technology due to the improved geometric accuracy, surface finish, and wear resistance of the material. Planetary Systems Corporation evaluated these components and determined that 3D printing is potentially a viable method for achieving significant cost and savings metrics.

  14. Does human body odor represent a significant and rewarding social signal to individuals high in social openness?

    Science.gov (United States)

    Lübke, Katrin T; Croy, Ilona; Hoenen, Matthias; Gerber, Johannes; Pause, Bettina M; Hummel, Thomas

    2014-01-01

    Across a wide variety of domains, experts differ from novices in their response to stimuli linked to their respective field of expertise. It is currently unknown whether similar patterns can be observed with regard to social expertise. The current study therefore focuses on social openness, a central social skill necessary to initiate social contact. Human body odors were used as social cues, as they inherently signal the presence of another human being. Using functional MRI, hemodynamic brain responses to body odors of women reporting a high (n = 14) or a low (n = 12) level of social openness were compared. Greater activation within the inferior frontal gyrus and the caudate nucleus was observed in high socially open individuals compared to individuals low in social openness. With the inferior frontal gyrus being a crucial part of the human mirror neuron system, and the caudate nucleus being implicated in social reward, it is discussed whether human body odor might constitute more of a significant and rewarding social signal to individuals high in social openness compared to individuals low in social openness process.

  15. Removal of odorous materials in carbonization process of dyeing wastewater sludge

    International Nuclear Information System (INIS)

    Bae, Sung-Keun; Woo, Byung-Kyu; Nam, In-Sick; Lee, Joo-Yong; Kim, Gi-Sun

    2010-01-01

    From drying process in a carbonization facility of dyeing wastewater sludge, noxious and odorous materials such as NH 3 , H 2 S, and Volatile Organic Compound (VOCs) contained in the sludge are emitted. In previous studies Regenerative Thermal Oxidizer (RTO) was verified as the most efficient method to eliminate them; nevertheless, it was very expensive to establish and operate because of fuel consumption. To estimate the feasibility of a water spray tower and bio-filter system, laboratory scale experiments for NH 3 , H 2 S, and toluene gas carried out. In case of water spray experiment for the single gas, the removal rate of NH 3 and H 2 S increased as decreasing the concentration, increasing the liquid/ gas ratio, and increasing the retention time. Toluene was eliminated as low as 20% regardless of the above operating parameters. The removal rates of NH 3 and H 2 S were 88∼98% and 80∼83%, respectively. For the mixed gas, the removal rates of NH 3 and toluene was a little dropped, but H 2 S was eliminated slightly more as compared with single gas experiment. Water spray system was not effective for toluene, but it was removed over 90% in bio-filter system. Retention time of gas in bio-filter bed might be an important operating parameter and its optimal condition was considered to 60 seconds. It is experimentally verified that odorous material was very effectively removed by a water spray tower and bio-filter combined system. (author)

  16. Sex and repeated restraint stress interact to affect cat odor-induced defensive behavior in adult rats.

    Science.gov (United States)

    Perrot-Sinal, Tara S; Gregus, Andrea; Boudreau, Daniel; Kalynchuk, Lisa E

    2004-11-19

    The overall objective of the present experiment was to assess sex differences in the effects of repeated restraint stress on fear-induced defensive behavior and general emotional behavior. Groups of male and female Long-Evans rats received either daily restraint stress (stressed) or daily brief handling (nonstressed) for 21 consecutive days. On days 22-25, a number of behavioral tests were administered concluding with a test of defensive behavior in response to a predatory odor. Stressed and nonstressed males and females were exposed to a piece of cat collar previously worn by a female domestic cat (cat odor) or a piece of collar never worn by a cat (control odor) in a familiar open field containing a hide barrier. Rats displayed pronounced defensive behavior (increased hiding and risk assessment) and decreased nondefensive behavior (grooming, rearing) in response to the cat odor. Nonstressed females exposed to cat odor displayed less risk assessment behavior relative to nonstressed males exposed to cat odor. Restraint stress had little effect on defensive behavior in male rats but significantly increased risk assessment behaviors in females. Behavior on the Porsolt forced swim test (a measure of depression-like behavior) and the open field test (a measure of anxiety-like behavior) was not affected by stress or sex. These findings indicate the utility of the predator odor paradigm in detecting subtle shifts in naturally occurring anxiety-like behaviors that may occur differentially in males and females.

  17. Odorant normative data for use in olfactory memory experiments: Dimension selection and analysis of individual differences.

    Directory of Open Access Journals (Sweden)

    Andrew Gordon Moss

    2016-08-01

    Full Text Available The present study reports normative ratings for 200 food and non-food odors. One hundred participants rated odors across measures of verbalisability, perceived descriptive ability, context availability, pleasantness, irritability, intensity, familiarity, frequency, age of acquisition, and complexity. Analysis of the agreement between raters revealed that four dimensions, those of familiarity, intensity, pleasantness, and irritability, have the strongest utility as normative data. The ratings for the remaining dimensions exhibited reduced discriminability across the odor set and should therefore be used with caution. Indeed, these dimensions showed a larger difference between individuals in the ratings of the odors. Familiarity was shown to be related to pleasantness, and a non-linear relationship between pleasantness and intensity was observed which reflects greater intensity for odors that elicit a strong hedonic response. The suitability of these data for use in future olfactory study is considered, and effective implementation of the data for controlling stimuli is discussed.

  18. Integral approaches to wastewater treatment plant upgrading for odor prevention: Activated Sludge and Oxidized Ammonium Recycling.

    Science.gov (United States)

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

    2015-11-01

    Traditional physical/chemical end-of-the-pipe technologies for odor abatement are relatively expensive and present high environmental impacts. On the other hand, biotechnologies have recently emerged as cost-effective and environmentally friendly alternatives but are still limited by their investment costs and land requirements. A more desirable approach to odor control is the prevention of odorant formation before being released to the atmosphere, but limited information is available beyond good design and operational practices of the wastewater treatment process. The present paper reviews two widely applicable and economic alternatives for odor control, Activated Sludge Recycling (ASR) and Oxidized Ammonium Recycling (OAR), by discussing their fundamentals, key operating parameters and experience from the available pilot and field studies. Both technologies present high application potential using readily available plant by-products with a minimum plant upgrading, and low investment and operating costs, contributing to the sustainability and economic efficiency of odor control at wastewater treatment facilities. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Resolving the chemical structures of off-odorants and potentially harmful substances in toys-example of children's swords.

    Science.gov (United States)

    Denk, Philipp; Velasco-Schön, Cristina; Buettner, Andrea

    2017-09-01

    Most children's toys on the market are primarily made out of plastic and other complex composite materials. Consumer complaints about offensive odors or irritating effects associated with toy products have increased in recent years. One example is the strongly perceivable negative odor reported for a particular series of toy swords. Characterizing the presence of contaminants, including those that have the potential to be deleterious to health, in such products is a significant analytical challenge due to the high baseline abundance of chemical constituents of the materials used in the products. In the present study, the nature of offensive odorants associated with toy sword products was examined by gas chromatography (GC). After initial sensory evaluations, the volatile compounds from the toy products were recovered using solvent extraction and solvent-assisted flavor evaporation. The extracts were analyzed using GC-olfactometry (GC-O) and two-dimensional GC-O coupled with mass spectrometry (GC-GC-MS/O). A total of 26 odor-active compounds, including aromatic hydrocarbons and phenols, were identified among numerous non-odorous volatile by-products. These substances also included polycyclic aromatic hydrocarbons, which were analyzed by GC-MS. Representative substances were naphthalene and 1,2-dihydronaphthalene that exhibited moldy, mothball-like odor impressions, and phenol derivatives with leather-like, phenolic, horse-stable-like smells. The odorants detected correlated with the assigned attributes from the sensory analyses. This study clearly shows that the detection and identification of such odorous contaminants can provide key indications of potentially harmful yet unknown substances in everyday products such as toys. Graphical abstract ᅟ.

  20. SMELL-S and SMELL-R: Olfactory tests not influenced by odor-specific insensitivity or prior olfactory experience.

    Science.gov (United States)

    Hsieh, Julien W; Keller, Andreas; Wong, Michele; Jiang, Rong-San; Vosshall, Leslie B

    2017-10-24

    Smell dysfunction is a common and underdiagnosed medical condition that can have serious consequences. It is also an early biomarker of neurodegenerative diseases, including Alzheimer's disease, where olfactory deficits precede detectable memory loss. Clinical tests that evaluate the sense of smell face two major challenges. First, human sensitivity to individual odorants varies significantly, so test results may be unreliable in people with low sensitivity to a test odorant but an otherwise normal sense of smell. Second, prior familiarity with odor stimuli can bias smell test performance. We have developed nonsemantic tests for olfactory sensitivity (SMELL-S) and olfactory resolution (SMELL-R) that use mixtures of odorants that have unfamiliar smells. The tests can be self-administered by healthy individuals with minimal training and show high test-retest reliability. Because SMELL-S uses odor mixtures rather than a single molecule, odor-specific insensitivity is averaged out, and the test accurately distinguished people with normal and dysfunctional smell. SMELL-R is a discrimination test in which the difference between two stimulus mixtures can be altered stepwise. This is an advance over current discrimination tests, which ask subjects to discriminate monomolecular odorants whose difference in odor cannot be quantified. SMELL-R showed significantly less bias in scores between North American and Taiwanese subjects than conventional semantically based smell tests that need to be adapted to different languages and cultures. Based on these proof-of-principle results in healthy individuals, we predict that SMELL-S and SMELL-R will be broadly effective in diagnosing smell dysfunction. Published under the PNAS license.

  1. SMELL-S and SMELL-R: Olfactory tests not influenced by odor-specific insensitivity or prior olfactory experience

    Science.gov (United States)

    Jiang, Rong-San

    2017-01-01

    Smell dysfunction is a common and underdiagnosed medical condition that can have serious consequences. It is also an early biomarker of neurodegenerative diseases, including Alzheimer’s disease, where olfactory deficits precede detectable memory loss. Clinical tests that evaluate the sense of smell face two major challenges. First, human sensitivity to individual odorants varies significantly, so test results may be unreliable in people with low sensitivity to a test odorant but an otherwise normal sense of smell. Second, prior familiarity with odor stimuli can bias smell test performance. We have developed nonsemantic tests for olfactory sensitivity (SMELL-S) and olfactory resolution (SMELL-R) that use mixtures of odorants that have unfamiliar smells. The tests can be self-administered by healthy individuals with minimal training and show high test–retest reliability. Because SMELL-S uses odor mixtures rather than a single molecule, odor-specific insensitivity is averaged out, and the test accurately distinguished people with normal and dysfunctional smell. SMELL-R is a discrimination test in which the difference between two stimulus mixtures can be altered stepwise. This is an advance over current discrimination tests, which ask subjects to discriminate monomolecular odorants whose difference in odor cannot be quantified. SMELL-R showed significantly less bias in scores between North American and Taiwanese subjects than conventional semantically based smell tests that need to be adapted to different languages and cultures. Based on these proof-of-principle results in healthy individuals, we predict that SMELL-S and SMELL-R will be broadly effective in diagnosing smell dysfunction. PMID:29073044

  2. The capsaicin cough reflex in patients with symptoms elicited by odorous chemicals

    DEFF Research Database (Denmark)

    Holst, H.; Arendt-Nielsen, Lars; Mosbech, H.

    2010-01-01

    between groups in age, body mass index or pulmonary function. The median C5 were 129 micromol/L (control group), 48 micromol/L (multiple chemical sensitivity patients), 32 micromol/L (eczema patients). The reporting of lower airway symptoms from odorous chemicals was significantly (p......Patients with multiple chemical sensitivity and eczema patients with airway symptoms elicited by odorous chemicals have enhanced cough reflex to capsaicin when applying the tidal breathing method. The aims of the present study were to test whether the capsaicin induced cough reflex was enhanced...... when applying the single breath inhalation method in similar groups of patients with symptoms related to odorous chemicals e.g. other persons wearing of perfume; and to investigate to what extent the reporting of lower airway symptoms influenced the cough reflex. Sixteen patients fulfilling Cullen...

  3. Odor-induced recall of emotional memories in PTSD-Review and new paradigm for research

    NARCIS (Netherlands)

    Daniels, Judith K.; Vermetten, Eric

    2016-01-01

    It is clinically well known that olfactory intrusions in PTSD can be a disabling phenomena due to the involuntary recall of odor memories. Odorants can trigger involuntary recall of emotional memories as well have the potential to help diminishing emotional arousal as grounding stimuli. Despite

  4. Grammatical gender affects odor cognition

    OpenAIRE

    Speed, L.J.; Majid, A.

    2016-01-01

    Language interacts with olfaction in exceptional ways. Olfaction is believed to be weakly linked with language, as demonstrated by our poor odor naming ability, yet olfaction seems to be particularly susceptible to linguistic descriptions. We tested the boundaries of the influence of language on olfaction by focusing on a non-lexical aspect of language (grammatical gender). We manipulated the grammatical gender of fragrance descriptions to test whether the congruence with fragrance gender wou...

  5. Molecular determinants of odorant receptor function in insects

    Indian Academy of Sciences (India)

    2014-07-20

    Jul 20, 2014 ... other host-odor responsive receptors from vector insect spe- cies would .... those that mediate host-seeking behaviour in insect disease vectors and ... receptors are transmitted and processed via olfactory circuits. (Vosshall ...

  6. Identification of Glossina morsitans morsitans odorant binding ...

    African Journals Online (AJOL)

    Tsetse flies are vectors of trypanosome parasites, causative agents of Trypanosomiasis in humans and animals. Odorant Binding Proteins (OBPs) are critical in insect olfaction as they bind volatile odours from the environment and transport them to receptors within olfactory receptor neurons for processing providing critical ...

  7. Paradoxical Neurobehavioral Rescue by Memories of Early-Life Abuse: The Safety Signal Value of Odors Learned during Abusive Attachment

    Science.gov (United States)

    Raineki, Charlis; Sarro, Emma; Rincón-Cortés, Millie; Perry, Rosemarie; Boggs, Joy; Holman, Colin J; Wilson, Donald A; Sullivan, Regina M

    2015-01-01

    Caregiver-associated cues, including those learned in abusive attachment, provide a sense of safety and security to the child. Here, we explore how cues associated with abusive attachment, such as maternal odor, can modify the enduring neurobehavioral effects of early-life abuse. Two early-life abuse models were used: a naturalistic paradigm, where rat pups were reared by an abusive mother; and a more controlled paradigm, where pups underwent peppermint odor-shock conditioning that produces an artificial maternal odor through engagement of the attachment circuit. Animals were tested for maternal odor preference in infancy, forced swim test (FST), social behavior, and sexual motivation in adulthood—in the presence or absence of maternal odors (natural or peppermint). Amygdala odor-evoked local field potentials (LFPs) via wireless electrodes were also examined in response to the maternal odors in adulthood. Both early-life abuse models induced preference for the maternal odors in infancy. In adulthood, these early-life abuse models produced FST deficits and decreased social behavior, but did not change sexual motivation. Presentation of the maternal odors rescued FST and social behavior deficits induced by early-life abuse and enhanced sexual motivation in all animals. In addition, amygdala LFPs from both abuse animal models showed unique activation within the gamma frequency (70–90 Hz) bands in response to the specific maternal odor present during early-life abuse. These results suggest that attachment-related cues learned during infancy have a profound ability to rescue neurobehavioral dysregulation caused by early-life abuse. Paradoxically, abuse-associated cues seem to acquire powerful and enduring antidepressive properties and alter amygdala modulation. PMID:25284320

  8. Paradoxical neurobehavioral rescue by memories of early-life abuse: the safety signal value of odors learned during abusive attachment.

    Science.gov (United States)

    Raineki, Charlis; Sarro, Emma; Rincón-Cortés, Millie; Perry, Rosemarie; Boggs, Joy; Holman, Colin J; Wilson, Donald A; Sullivan, Regina M

    2015-03-01

    Caregiver-associated cues, including those learned in abusive attachment, provide a sense of safety and security to the child. Here, we explore how cues associated with abusive attachment, such as maternal odor, can modify the enduring neurobehavioral effects of early-life abuse. Two early-life abuse models were used: a naturalistic paradigm, where rat pups were reared by an abusive mother; and a more controlled paradigm, where pups underwent peppermint odor-shock conditioning that produces an artificial maternal odor through engagement of the attachment circuit. Animals were tested for maternal odor preference in infancy, forced swim test (FST), social behavior, and sexual motivation in adulthood-in the presence or absence of maternal odors (natural or peppermint). Amygdala odor-evoked local field potentials (LFPs) via wireless electrodes were also examined in response to the maternal odors in adulthood. Both early-life abuse models induced preference for the maternal odors in infancy. In adulthood, these early-life abuse models produced FST deficits and decreased social behavior, but did not change sexual motivation. Presentation of the maternal odors rescued FST and social behavior deficits induced by early-life abuse and enhanced sexual motivation in all animals. In addition, amygdala LFPs from both abuse animal models showed unique activation within the gamma frequency (70-90 Hz) bands in response to the specific maternal odor present during early-life abuse. These results suggest that attachment-related cues learned during infancy have a profound ability to rescue neurobehavioral dysregulation caused by early-life abuse. Paradoxically, abuse-associated cues seem to acquire powerful and enduring antidepressive properties and alter amygdala modulation.

  9. Divergence in male sexual odor signal and genetics across populations of the red mason bee, Osmia bicornis, in Europe.

    Science.gov (United States)

    Conrad, Taina; Paxton, Robert J; Assum, Günter; Ayasse, Manfred

    2018-01-01

    In some insect species, females may base their choice for a suitable mate on male odor. In the red mason bee, Osmia bicornis, female choice is based on a male's odor bouquet as well as its thorax vibrations, and its relatedness to the female, a putative form of optimal outbreeding. Interestingly, O. bicornis can be found as two distinct color morphs in Europe, which are thought to represent subspecies and between which we hypothesize that female discrimination may be particularly marked. Here we investigated (i) if these two colors morphs do indeed represent distinct, reproductively differentiated populations, (ii) how odor bouquets of male O. bicornis vary within and between populations, and (iii) whether variation in male odor correlates with genetic distance, which might represent a cue by which females could optimally outbreed. Using GC and GC-MS analysis of male odors and microsatellite analysis of males and females from 9 populations, we show that, in Denmark, an area of subspecies sympatry, the two color morphs at any one site do not differ, either in odor bouquet or in population genetic differentiation. Yet populations across Europe are distinct in their odor profile as well as being genetically differentiated. Odor differences do not, however, mirror genetic differentiation between populations. We hypothesize that populations from Germany, England and Denmark may be under sexual selection through female choice for local odor profiles, which are not related to color morph though which could ultimately lead to population divergence and speciation.

  10. Programming of stress-related behavior and epigenetic neural gene regulation in mice offspring through maternal exposure to predator odor

    Science.gov (United States)

    St-Cyr, Sophie; McGowan, Patrick O.

    2015-01-01

    Perinatal stress mediated through the mother can lead to long-term alterations in stress-related phenotypes in offspring. The capacity for adaptation to adversity in early life depends in part on the life history of the animal. This study was designed to examine the behavioral and neural response in adult offspring to prenatal exposure to predator odor: an ethologically-relevant psychological stressor. Pregnant mice were exposed daily to predator odors or distilled water control over the second half of the pregnancy. Predator odor exposure lead to a transient decrease in maternal care in the mothers. As adults, the offspring of predator odor-exposed mothers showed increased anti-predator behavior, a predator-odor induced decrease in activity and, in female offspring, an increased corticosterone (CORT) response to predator odor exposure. We found a highly specific response among stress-related genes within limbic brain regions. Transcript abundance of Corticotropin-releasing hormone receptor 1 (CRHR1) was elevated in the amygdala in adult female offspring of predator odor-exposed mothers. In the hippocampus of adult female offspring, decreased Brain-derived neurotrophic factor (BDNF) transcript abundance was correlated with a site-specific decrease in DNA methylation in Bdnf exon IV, indicating the potential contribution of this epigenetic mechanism to maternal programming by maternal predator odor exposure. These data indicate that maternal predator odor exposure alone is sufficient to induce an altered stress-related phenotype in adulthood, with implications for anti-predator behavior in offspring. PMID:26082698

  11. On the Communicative Function of Body Odors.

    Science.gov (United States)

    de Groot, Jasper H B; Semin, Gün R; Smeets, Monique A M

    2017-03-01

    Humans use multiple senses to navigate the social world, and the sense of smell is arguably the most underestimated one. An intriguing aspect of the sense of smell is its social communicative function. Research has shown that human odors convey information about a range of states (e.g., emotions, sickness) and traits (e.g., individuality, gender). Yet, what underlies the communicability of these states and traits via smell? We fill this explanatory gap with a framework that highlights the dynamic and flexible aspects of human olfactory communication. In particular, we explain how chemical profiles, associative learning (i.e., the systematic co-occurrence of chemical profiles with state- or trait-related information), and top-down contextual influences could interact to shape human odor perception. Our model not only helps to integrate past research on human olfactory communication but it also opens new avenues for future research on this fascinating, yet to date poorly understood, field.

  12. Blocking oxytocin receptors inhibits vaginal marking to male odors in female Syrian hamsters.

    Science.gov (United States)

    Martinez, Luis A; Albers, H Elliott; Petrulis, Aras

    2010-12-02

    In Syrian hamsters (Mesocricetus auratus), precopulatory behaviors such as vaginal scent marking are essential for attracting a suitable mate. Vaginal marking is dependent on forebrain areas implicated in the neural regulation of reproductive behaviors in rodents, including the medial preoptic/anterior hypothalamus (MPOA-AH). Within MPOA-AH, the neuropeptide oxytocin (OT) acts to facilitate copulation (lordosis), as well as ultrasonic vocalizations towards males. It is not known, however, if OT in this area also facilitates vaginal marking. In the present study, a specific oxytocin receptor antagonist (OTA) was injected into MPOA-AH of intact female Syrian hamsters to determine if oxytocin receptor-dependent signaling is critical for the normal expression of vaginal marking elicited by male, female, and clean odors. OTA injections significantly inhibited vaginal marking in response to male odors compared with vehicle injections. There was no effect of OTA on marking in response to either female or clean odors. When injected into the bed nucleus of the stria terminalis (BNST), a nearby region to MPOA-AH, OTA was equally effective in decreasing marking. Finally, the effects of OTA appear to be specific to vaginal marking, as OTA injections in MPOA-AH or BNST did not alter general locomotor activity, flank marking, or social odor investigation. Considered together, these results suggest that OT in MPOA-AH and/or BNST normally facilitates male odor-induced vaginal marking, providing further evidence that OT generally supports prosocial interactions among conspecifics. Copyright © 2010 Elsevier Inc. All rights reserved.

  13. The predatory mite Phytoseiulus persimilis does not perceive odor mixtures as strictly elemental objects.

    Science.gov (United States)

    van Wijk, Michiel; de Bruijn, Paulien J A; Sabelis, Maurice W

    2010-11-01

    Phytoseiulus persimilis is a predatory mite that in absence of vision relies on the detection of herbivore-induced plant odors to locate its prey, the two-spotted spider-mite Tetranychus urticae. This herbivorous prey is feeding on leaves of a wide variety of plant species in different families. The predatory mites respond to numerous structurally different compounds. However, typical spider-mite induced plant compounds do not attract more predatory mites than plant compounds not associated with prey. Because the mites are sensitive to many compounds, components of odor mixtures may affect each other's perception. Although the response to pure compounds has been well documented, little is known how interactions among compounds affect the response to odor mixtures. We assessed the relation between the mites' responses elicited by simple mixtures of two compounds and by the single components of these mixtures. The preference for the mixture was compared to predictions under three conceptual models, each based on one of the following assumptions: (1) the responses elicited by each of the individual components can be added to each other; (2) they can be averaged; or (3) one response overshadows the other. The observed response differed significantly from the response predicted under the additive response, average response, and overshadowing response model in 52, 36, and 32% of the experimental tests, respectively. Moreover, the behavioral responses elicited by individual compounds and their binary mixtures were determined as a function of the odor concentration. The relative contribution of each component to the behavioral response elicited by the mixture varied with the odor concentration, even though the ratio of both compounds in the mixture was kept constant. Our experiments revealed that compounds that elicited no response had an effect on the response elicited by binary mixtures that they were part of. The results are not consistent with the hypothesis that P

  14. Attractiveness of MM-X traps baited with human or synthetic odor to mosquitoes (Diptera: Culicidae) in The Gambia

    NARCIS (Netherlands)

    Qiu, Y.T.; Smallegange, R.C.; Braak, ter C.J.F.; Spitzen, J.; Loon, van J.J.A.; Jawara, M.; Milligan, P.; Galimard, A.M.S.; Beek, van T.A.; Knols, B.G.J.; Takken, W.

    2007-01-01

    Chemical cues play an important role in the host-seeking behavior of blood-feeding mosquitoes (Diptera: Culicidae). A field study was carried out in The Gambia to investigate the effects of human odor or synthetic odor blends on the attraction of mosquitoes. MM-X traps baited with 16 odor blends to

  15. Antennal Transcriptome Analysis of Odorant Reception Genes in the Red Turpentine Beetle (RTB, Dendroctonus valens.

    Directory of Open Access Journals (Sweden)

    Xiao-Cui Gu

    Full Text Available The red turpentine beetle (RTB, Dendroctonus valens LeConte (Coleoptera: Curculionidae, Scolytinae, is a destructive invasive pest of conifers which has become the second most important forest pest nationwide in China. Dendroctonus valens is known to use host odors and aggregation pheromones, as well as non-host volatiles, in host location and mass-attack modulation, and thus antennal olfaction is of the utmost importance for the beetles' survival and fitness. However, information on the genes underlying olfaction has been lacking in D. valens. Here, we report the antennal transcriptome of D. valens from next-generation sequencing, with the goal of identifying the olfaction gene repertoire that is involved in D. valens odor-processing.We obtained 51 million reads that were assembled into 61,889 genes, including 39,831 contigs and 22,058 unigenes. In total, we identified 68 novel putative odorant reception genes, including 21 transcripts encoding for putative odorant binding proteins (OBP, six chemosensory proteins (CSP, four sensory neuron membrane proteins (SNMP, 22 odorant receptors (OR, four gustatory receptors (GR, three ionotropic receptors (IR, and eight ionotropic glutamate receptors. We also identified 155 odorant/xenobiotic degradation enzymes from the antennal transcriptome, putatively identified to be involved in olfaction processes including cytochrome P450s, glutathione-S-transferases, and aldehyde dehydrogenase. Predicted protein sequences were compared with counterparts in Tribolium castaneum, Megacyllene caryae, Ips typographus, Dendroctonus ponderosae, and Agrilus planipennis.The antennal transcriptome described here represents the first study of the repertoire of odor processing genes in D. valens. The genes reported here provide a significant addition to the pool of identified olfactory genes in Coleoptera, which might represent novel targets for insect management. The results from our study also will assist with evolutionary

  16. The effect of pyrazine odor on avoidance learning and memory in wild robins Erithacus rubecula

    Directory of Open Access Journals (Sweden)

    Emma C. SIDDALL, Nicola M. MARPLES

    2011-04-01

    Full Text Available Toxic insects advertise their defended state to potential predators using warning displays. Frequently these displays use cues through more than one sensory modality, and combine color, smell and sound to produce a multimodal warning display. Signalling through more than one sensory pathway may enhance the rate of avoidance learning, and the memorability of the learned avoidance. A common insect warning odor, pyrazine, has previously been shown to increase the rate of learned avoidance of unpalatable yellow prey by domestic chicks (Gallus gallus domesticus, and the odor also improved memory of this learned avoidance. However, to date no research has examined this response to pyrazine odor using wild birds under natural conditions. This study used wild robins (Erithacus rubecula to investigate whether wild birds avoided yellow baits that smelled of pyrazine more strongly than those presented with no odor. The results provide some evidence that pyrazine odor does increase the level of protection an aposematic insect gains from a wild avian predator, but that the effect of pyrazine on learned avoidance was much weaker than was found with domestic chicks [Current Zoology 57 (2: 208–214, 2011].

  17. Assessment of Olfactory Function in MAPT-Associated Neurodegenerative Disease Reveals Odor-Identification Irreproducibility as a Non-Disease-Specific, General Characteristic of Olfactory Dysfunction.

    Science.gov (United States)

    Markopoulou, Katerina; Chase, Bruce A; Robowski, Piotr; Strongosky, Audrey; Narożańska, Ewa; Sitek, Emilia J; Berdynski, Mariusz; Barcikowska, Maria; Baker, Matt C; Rademakers, Rosa; Sławek, Jarosław; Klein, Christine; Hückelheim, Katja; Kasten, Meike; Wszolek, Zbigniew K

    2016-01-01

    limitations of these tests used and the sample sizes, olfactory dysfunction appears to be associated with the inability to identify odors reliably and consistently, not with the loss of an ability to identify specific odors. Irreproducibility in odor identification appears to be a non-disease-specific, general feature of olfactory dysfunction that is accelerated or accentuated in neurodegenerative disease. It may reflect a fundamental organizational principle of the olfactory system, which is more "error-prone" than other sensory systems.

  18. Assessment of Olfactory Function in MAPT-Associated Neurodegenerative Disease Reveals Odor-Identification Irreproducibility as a Non-Disease-Specific, General Characteristic of Olfactory Dysfunction.

    Directory of Open Access Journals (Sweden)

    Katerina Markopoulou

    reflect the limitations of these tests used and the sample sizes, olfactory dysfunction appears to be associated with the inability to identify odors reliably and consistently, not with the loss of an ability to identify specific odors. Irreproducibility in odor identification appears to be a non-disease-specific, general feature of olfactory dysfunction that is accelerated or accentuated in neurodegenerative disease. It may reflect a fundamental organizational principle of the olfactory system, which is more "error-prone" than other sensory systems.

  19. The Scent of Roses and beyond: Molecular Structures, Analysis, and Practical Applications of Odorants

    Science.gov (United States)

    Mannschreck, Albrecht; von Angerer, Erwin

    2011-01-01

    A few odorous compounds found in roses are chosen to arouse the reader's interest in their molecular structures. This article differs from some similar reports on odorants mainly by combining the structural description with the presentation of the following types of isomers: constitutional isomers, enantiomers, and diastereomers. The preparation…

  20. Multisensory integration for odor tracking by flying Drosophila: Behavior, circuits and speculation

    OpenAIRE

    Duistermars, Brian J; Frye, Mark A

    2010-01-01

    Many see fruit flies as an annoyance, invading our homes with a nagging persistence and efficiency. Yet from a scientific perspective, these tiny animals are a wonder of multisensory integration, capable of tracking fragmented odor plumes amidst turbulent winds and constantly varying visual conditions. The peripheral olfactory, mechanosensory, and visual systems of the fruit fly, Drosophila melanogaster, have been studied in great detail;1–4 however, the mechanisms by which fly brains integra...