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Sample records for fresh green odor

  1. Fresh squeezed orange juice odor: a review.

    PubMed

    Perez-Cacho, Pilar Ruiz; Rouseff, Russell L

    2008-08-01

    Fresh orange juice is a highly desirable but unstable product. This review examines analytical findings, odor activity, and variations due to cultivar, sampling methods, manner of juicing, plus possible enzymatic and microbial artifacts. Initial attempts to characterize orange juice odor were based on volatile quantitation and overemphasized the importance of high concentration volatiles. Although over 300 volatiles have been reported from GC-MS analytical studies, this review presents 36 consensus aroma active components from GC-olfactometry studies consisting of 14 aldehydes, 7 esters, 5 terpenes, 6 alcohols, and 4 ketones. Most are trace (microg/L) components. (+)-Limonene is an essential component in orange juice odor although its exact function is still uncertain. Total amounts of volatiles in mechanically squeezed juices are three to 10 times greater than hand-squeezed juices because of elevated peel oil levels. Elevated peel oil changes the relative proportion of several key odorants. Odor active components from solvent extraction studies differ from those collected using headspace techniques as they include volatiles with low vapor pressure such as vanillin. Some reported odorants such as 2,3-butanedione are microbial contamination artifacts. Orange juice odor models confirm that fresh orange aroma is complex as the most successful models contain 23 odorants. PMID:18663618

  2. Composition of key offensive odorants released from fresh food materials

    NASA Astrophysics Data System (ADS)

    Kim, Ki-Hyun; Kim, Yong-Hyun

    2014-06-01

    A refrigerator loaded with a variety of foods without sealed packaging can create quite an olfactory nuisance, and it may come as a surprise that fresh foods emit unpleasant odorants just as those that are decaying. To learn more about nuisance sources in our daily lives, we measured a list of 22 compounds designated as the key offensive odorants (e.g., reduced sulfur, nitrogenous, volatile fatty acid (VFA), and carbonyls) from nine types of common food items consumed in S. Korea: raw beef, raw fish, spam, yolks and albumin of boiled eggs (analyzed separately), milk, cheese, onions, and strawberries. The odor intensity (OI) of each food item was computed initially with the aid of previously used empirical equations. This indicates that the malodor properties of target foods tend to be governed by a few key odorants such as VFA, S, and N compounds. The extent of odorant mixing of a given food was then evaluated by exploring the correlation between the human olfaction (e.g., dilution-to-threshold (D/T) ratio) and the odor potential determined indirectly (instrumentally) such as odor activity value (OAV) or sum of odor intensity (SOI). The overall results of our study confirm the existence of malodorant compounds released from common food items and their contribution to their odor characteristics to a certain degree.

  3. Evaluation of Food Freshness and Locality by Odor Sensor

    NASA Astrophysics Data System (ADS)

    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.

  4. Analysis of Key Odorants in Roasted Green Tea

    NASA Astrophysics Data System (ADS)

    Mizukami, Yuzo; Sawai, Yusuke; Yamaguchi, Yuichi

    This research aims to identify key odorants in roasted green tea. The aroma extract dilution analysis revealed 25 odor-active peaks with the flavor dilution factors of ≥ 16. We identified 2-ethyl-3,5-dimethylpyrazine as the most important odorant in roasted green tea with the highest flavor dilution factor of 4096. In addition, tetramethylpyrazine, 2,3-diethyl-5- methylpyrazine were also detected as potent odorants with the high flavor dilution factors. These three alkylpyrazines would be key contributors to aroma of roasted green tea.

  5. Comparison of two dynamic measurement methods of odor and odorant emission rates from freshly dewatered biosolids.

    PubMed

    Wang, Tingting; Sattayatewa, Chakkrid; Venkatesan, Dhesikan; Noll, Kenneth E; Pagilla, Krishna R; Moschandreas, Demetrios J

    2011-06-01

    Odor and odorant emission rates from freshly dewatered biosolids in a dewatering building of a Water Reclamation Plant (WRP) are measured using the EPA flux chamber and wind tunnel methods. Experimental results are compared statistically to test whether the two methods result in similar emission rates when experiments are performed under field conditions. To the best of our knowledge the literature is void of studies comparing the two methods indoors. In this paper the two methods are compared indoors where the wind velocity and air exchange rate are pertinent field conditions and can be measured. The difference between emission rates of odor and hydrogen sulfide measured with the two methods is not statistically significant (P values: 0.505 for odor, 0.130 for H(2)S). It is concluded that both methods can be used to estimate source emissions but selection of the most effective or efficient method depends on prevailing environmental conditions. The wind tunnel is appropriate for outdoor environments where wind effects on source emissions are more pronounced than indoors. The EPA flux chamber depends on the air exchange rate of the chamber, which simulates corresponding conditions of the indoor environment under investigation and is recommended for estimation of indoor pollution sources. PMID:21552636

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

    NASA Astrophysics Data System (ADS)

    Fanaro, G. B.; Duarte, R. C.; Araújo, 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.

  7. Odor-active constituents in fresh pineapple (Ananas comosus [L.] Merr.) by quantitative and sensory evaluation.

    PubMed

    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. PMID:16041138

  8. Meat and Fish Freshness Inspection System Based on Odor Sensing

    PubMed Central

    Hasan, Najam ul; Ejaz, Naveed; Ejaz, Waleed; Kim, Hyung Seok

    2012-01-01

    We propose a method for building a simple electronic nose based on commercially available sensors used to sniff in the market and identify spoiled/contaminated meat stocked for sale in butcher shops. Using a metal oxide semiconductor-based electronic nose, we measured the smell signature from two of the most common meat foods (beef and fish) stored at room temperature. Food samples were divided into two groups: fresh beef with decayed fish and fresh fish with decayed beef. The prime objective was to identify the decayed item using the developed electronic nose. Additionally, we tested the electronic nose using three pattern classification algorithms (artificial neural network, support vector machine and k-nearest neighbor), and compared them based on accuracy, sensitivity, and specificity. The results demonstrate that the k-nearest neighbor algorithm has the highest accuracy. PMID:23202222

  9. Odorization

    SciTech Connect

    Not Available

    1980-01-01

    The symposium on Odorization was held on August 19-21, 1980 in Chicago, Illinois. The intent of the symposium was to provide a thorough grounding in the fundamentals, current technology, and operating practices of odorization in the gas utility industry. A total of thirty one papers were presented covering a wide range of odorization topics from the behavior of the human olfactory system to odorant handling equipment, legal requirements, product liability, and litigation along with recent research and development in that area.

  10. Identification of Key Odorants in Withering-Flavored Green Tea by Aroma Extract Dilution Analysis

    NASA Astrophysics Data System (ADS)

    Mizukami, Yuzo; Yamaguchi, Yuichi

    This research aims to identify key odorants in withering-flavored green tea. Application of the aroma extract dilution analysis using the volatile fraction of green tea and withering-flavored green tea revealed 25 and 35 odor-active peaks with the flavor dilution factors of≥4, respectively. 4-mercapto-4-methylpentan-2-one, (E)-2-nonenal, linalool, (E,Z)-2,6-nonadienal and 3-methylnonane-2,4-dione were key odorants in green tea with the flavor dilution factor of≥16. As well as these 5 odorants, 1-octen-3-one, β-damascenone, geraniol, β-ionone, (Z)-methyljasmonate, indole and coumarine contributed to the withering flavor of green tea.

  11. Quantitative Analysis of Fragrance and Odorants Released from Fresh and Decaying Strawberries

    PubMed Central

    Kim, Yong-Hyun; Kim, Ki-Hyun; Szulejko, Jan E.; Parker, David

    2013-01-01

    The classes and concentrations of volatile organic compounds (VOC) released from fresh and decaying strawberries were investigated and compared. In this study, a total of 147 strawberry volatiles were quantified before and after nine days of storage to explore differences in the aroma profile between fresh strawberries (storage days (SRD) of 0, 1, and 3) and those that had started to decay (SRD = 6 and 9). In terms of concentration, seven compounds dominated the aroma profile of fresh strawberries (relative composition (RC) up to 97.4% by mass, sum concentration): (1) ethyl acetate = 518 mg·m−3, (2) methyl acetate = 239 mg·m−3, (3) ethyl butyrate = 13.5 mg·m−3, (4) methyl butyrate = 11.1 mg·m−3, (5) acetaldehyde = 24.9 mg·m−3, (6) acetic acid = 15.2 mg·m−3, and (7) acetone = 13.9 mg·m−3. In contrast, two alcohols dominated the aroma profile of decayed samples (RC up to 98.6%): (1) ethyl alcohol = 94.2 mg·m−3 and (2) isobutyl alcohol = 289 mg·m−3. Alternatively; if the aroma profiles are re-evaluated by summing odor activity values (ΣOAV); four ester compounds ((1) ethyl butyrate (6,160); (2) ethyl hexanoate (3,608); (3) ethyl isovalerate (1,592); and (4) ethyl 2-methylbutyrate (942)) were identified as the key constituents of fresh strawberry aroma (SRD-0). As the strawberries began to decay; isobutyl alcohol recorded the maximum OAV of 114 (relative proportion (RP) (SRD = 6) = 58.3%). However, as the decay process continued, the total OAV dropped further by 3 to 4 orders of magnitude—decreasing to 196 on SRD = 6 to 7.37 on SRD = 9. The overall results of this study confirm dramatic changes in the aroma profile of strawberries over time, especially with the onset of decay. PMID:23787728

  12. What is a fresh scent in perfumery? Perceptual freshness is correlated with substantivity.

    PubMed

    Zarzo, Manuel

    2013-01-01

    Perfumes are manufactured by mixing odorous materials with different volatilities. The parameter that measures the lasting property of a material when applied on the skin is called substantivity or tenacity. It is well known by perfumers that citrus and green notes are perceived as fresh and they tend to evaporate quickly, while odors most dissimilar to 'fresh' (e.g., oriental, powdery, erogenic and animalic scents) are tenacious. However, studies aimed at quantifying the relationship between fresh odor quality and substantivity have not received much attention. In this work, perceptual olfactory ratings on a fresh scale, estimated in a previous study, were compared with substantivity parameters and antierogenic ratings from the literature. It was found that the correlation between fresh odor character and odorant substantivity is quite strong (r = -0.85). 'Fresh' is sometimes interpreted in perfumery as 'cool' and the opposite of 'warm'. This association suggests that odor freshness might be somehow related to temperature. Assuming that odor perception space was shaped throughout evolution in temperate climates, results reported here are consistent with the hypothesis that 'fresh' evokes scents typically encountered in the cool season, while 'warm' would be evoked by odors found in nature during summer. This hypothesis is rather simplistic but it may provide a new insight to better understand the perceptual space of scents. PMID:23275083

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

    PubMed

    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. PMID:25259680

  14. Complete mitochondrial genome of the green odorous frog Odorrana margaretae (Anura: Ranidae).

    PubMed

    Chen, Zhuo; Zhang, Jie; Zhai, Xiaofei; Zhu, Yanjun; Chen, Xiaohong

    2015-06-01

    The complete mitochondrial genome (mitogenome) of the green odorous frog Odorrana margaretae (Anura: Ranidae) has been studied. The 17,903 bp circular genome contains the typical complement of 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and a control region. The AT content of the overall base compositon of H-strand is 56% and the length of control region is 2501 bp with 63.8% AT content. The arrangement of the protein-coding and ribosomal RNA genes was the same as that found in other anurans. The cluster of rearranged LTPF tRNA genes and the translocation of tRNA(His) gene into the D-loop region are observed. PMID:24938085

  15. What is a Fresh Scent in Perfumery? Perceptual Freshness is Correlated with Substantivity

    PubMed Central

    Zarzo, Manuel

    2013-01-01

    Perfumes are manufactured by mixing odorous materials with different volatilities. The parameter that measures the lasting property of a material when applied on the skin is called substantivity or tenacity. It is well known by perfumers that citrus and green notes are perceived as fresh and they tend to evaporate quickly, while odors most dissimilar to ‘fresh’ (e.g., oriental, powdery, erogenic and animalic scents) are tenacious. However, studies aimed at quantifying the relationship between fresh odor quality and substantivity have not received much attention. In this work, perceptual olfactory ratings on a fresh scale, estimated in a previous study, were compared with substantivity parameters and antierogenic ratings from the literature. It was found that the correlation between fresh odor character and odorant substantivity is quite strong (r = −0.85). ‘Fresh’ is sometimes interpreted in perfumery as ‘cool’ and the opposite of ‘warm’. This association suggests that odor freshness might be somehow related to temperature. Assuming that odor perception space was shaped throughout evolution in temperate climates, results reported here are consistent with the hypothesis that ‘fresh’ evokes scents typically encountered in the cool season, while ‘warm’ would be evoked by odors found in nature during summer. This hypothesis is rather simplistic but it may provide a new insight to better understand the perceptual space of scents. PMID:23275083

  16. Nutrient comparison of fresh and field-dried, green-seeded soybeans.

    PubMed

    Rasmussen, A I

    1978-06-01

    Nutrient composition and biologic utilization of cooked, dried, and ground meals prepared from fresh and field-dried, green-seeded edible soybeans were evaluated. On a dry-weight basis, nutrient content of the fresh and field-dried meals were comparable for protein, fat, calcium, phosphorus, magnesium, copper, and iron; fresh beans tended to have higher zinc content than the field-dried beans. Nutrient values for the green-seeded soybean meals were comparable to published values for full-fat soybean flour. Bioassay results indicated that protein efficiency ratios (PER) for rats fed casein were significantly better than those for the soybean-fed animals. Fresh, green-seeded soybean meal supported significantly better growth than did the field-dried, green-seeded soybean meal. Though significantly lower than that for the reference casein diet, the mean PER for fresh, green-seeded soybean meal was 90 per cent of that obtained with the reference casein. The nutrient analysis and protein bioassay data both indicate that green-seeded soybeans used as a vegetable item in the diet are a potentially significant food source of several important nutrients. PMID:566776

  17. Glycoalkaloid development during greening of fresh market potatoes (Solanum tuberosum L.).

    PubMed

    Grunenfelder, Laura A; Knowles, Lisa O; Hiller, Larry K; Knowles, N Richard

    2006-08-01

    Chlorophyll and glycoalkaloid synthesis in potato (Solanum tuberosum L.) tubers occur in direct response to light. The two processes are concurrent, but independent. Color photographic indices to subjectively grade fresh market potatoes for the extent of greening were developed under lighting conditions consistent with those of retail markets. Total glycoalkaloid (TGA) and chlorophyll accumulation for four cultivars were determined over the respective greening scales, thus calibrating the scales for TGA content. On average, TGA concentrations in complete longitudinal sections of tubers (flesh samples) were highest in Dark Red Norland followed by Russet Norkotah, Yukon Gold, and White Rose. TGA concentrations of flesh samples of White Rose and Yukon Gold tubers were somewhat variable and did not increase in direct proportion to greening level and chlorophyll content, particularly at higher levels of greening. TGA concentrations in Dark Red Norland and Russet Norkotah tubers were highly correlated (P < or = 0.001) with greening level and chlorophyll concentrations. When averaged over greening levels, skin samples contained 3.4- to 6.8-fold higher concentrations of TGAs than flesh samples, depending on the cultivar. The TGA concentration in periderm samples ranged from 37 to 160 mg/100 g of dry wt. Regardless of greening level, concentrations of TGAs in the flesh samples (including attached periderm) remained within limits presumed safe for human consumption. Discrimination of greened tubers on the basis of perceived glycoalkaloid toxicity is likely unfounded for the cultivars and greening levels studied. PMID:16881686

  18. Green biorefinery of fresh cattail for microalgal culture and ethanol production.

    PubMed

    Rahman, Quazi Mahzabin; Wang, Lijun; Zhang, Bo; Xiu, Shuangning; Shahbazi, Abolghasem

    2015-06-01

    Green biorefinery represents an appropriate approach to utilize the fresh aquatic biomass, eliminating the drying process of conventional bioenergy-converting system. In this study, fresh cattails were homogenized and then filtered, whereby cattails were separated into a fiber-rich cake and a nutrient-rich juice. The juice was used to cultivate microalgae Chlorella spp. in different media. In addition, the solid cake was pretreated with the sonication, and used as the feedstock for ethanol production. The results showed that the cattail juice could be a highly nutritious source for microalgae that are a promising feedstock for biofuels. Sugars released from the cattail cake were efficiently fermented to ethanol using Escherichia coli KO11, with 8.6-12.3% of the theoretical yield. The ultrasonic pretreatment was not sufficient for pretreating cattails. If a dilute acid pretreatment was applied, the conversion ratio of sugars from cattails has the potential to be over 85% of the theoretical value. PMID:25804533

  19. USE OF IONIZING RADIATION TO IMPROVE SENSORY AND MICROBIAL QUALITY OF FRESH-CUT GREEN ONION LEAVES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fresh-cut green onion leaves that received absorbed gamma radiation doses of 0, 1, 2 and 3 kGy were stored at 3 degrees Celsius for up to 14 day. Although 2 and 3 kGy radiation completely eliminated microflora population, the treatments resulted in increased cellular membrane damage, loss of aroma,...

  20. Effect of fresh green waste and green waste compost on mineral nitrogen, nitrous oxide and carbon dioxide from a Vertisol

    SciTech Connect

    Vaughan, Sarah M.; Dalal, Ram C.; Harper, Stephen M.; Menzies, Neal W.

    2011-08-15

    Incorporation of organic waste amendments to a horticultural soil, prior to expected risk periods, could immobilise mineral N, ultimately reducing nitrogen (N) losses as nitrous oxide (N{sub 2}O) and leaching. Two organic waste amendments were selected, a fresh green waste (FGW) and green waste compost (GWC) as they had suitable biochemical attributes to initiate N immobilisation into the microbial biomass and organic N forms. These characteristics include a high C:N ratio (FGW 44:1, GWC 35:1), low total N (<1%), and high lignin content (>14%). Both products were applied at 3 t C/ha to a high N (plus N fertiliser) or low N (no fertiliser addition) Vertisol soil in PVC columns. Cumulative N{sub 2}O production over the 28 day incubation from the control soil was 1.5 mg/N{sub 2}O/m{sup 2}, and 11 mg/N{sub 2}O/m{sup 2} from the control + N. The N{sub 2}O emission decreased with GWC addition (P < 0.05) for the high N soil, reducing cumulative N{sub 2}O emissions by 38% by the conclusion of the incubation. Analysis of mineral N concentrations at 7, 14 and 28 days identified that both FGW and GWC induced microbial immobilisation of N in the first 7 days of incubation regardless of whether the soil environment was initially high or low in N; with the FGW immobilising up to 30% of available N. It is likely that the reduced mineral N due to N immobilisation led to a reduced substrate for N{sub 2}O production during the first week of the trial, when soil N{sub 2}O emissions peaked. An additional finding was that FGW + N did not decrease cumulative N{sub 2}O emissions compared to the control + N, potentially due to the fact that it stimulated microbial respiration resulting in anaerobic micro sites in the soil and ultimately N{sub 2}O production via denitrification. Therefore, both materials could be used as post harvest amendments in horticulture to minimise N loss through nitrate-N leaching in the risk periods between crop rotations. The mature GWC has potential to reduce N

  1. Odorization II

    SciTech Connect

    Wilson, G.G.; Attari, A.A.

    1990-01-01

    Odorization is a small-scale but vital gas industry operation because of its important contribution to the safe use of gas. It is a field with complex technical problems related to the detection and behavior of the odorant materials used. In the 1987 symposium, a wide range of odorization topics was covered from the behavior of the human olfactory system to odorant handling equipment. Legal considerations and litigation were also included and, for the first time, presentations of LP gas odorization were given. The base of these proceedings is the speakers papers presented at the 1987 symposium supplemented with a number of unpublished papers from the 1984 session. In an effort to provide a comprehensive reference on the fundamentals and current practical technology of odorization in a single volume, a number of papers included in the 1980 symposium are also re-published here as well as one previously unpublished paper from the 1976 symposium. The volume is divided into the following nine sections: Introduction; Odorant Materials; Measurement of odor level; Measurement of odorant level; Automated odorization; LP gas odorization; Supplemental odorization; Odorization research; and Litigation. Forty-one papers have been indexed separately for inclusion on the data base.

  2. Effect of pretreatments and modified atmosphere packaging on the shelf life and quality of fresh- cut green bell pepper.

    PubMed

    Ranjitha, K; Sudhakar Rao, D V; Shivashankara, K S; Roy, Tapas Kumar

    2015-12-01

    Present study was aimed at understanding the effect of pretreatments and modified atmosphere packaging on the quality of fresh-cut green bell pepper (Capsicum annuum L.) during low temperature storage. Dip treatment of freshly cut green bell pepper pieces in 2 % calcium propionate followed by surface drying and subsequent packing in cryovac PD961 film which maintained an equilibrium modified atmosphere of 13-14 % O2 and 7 % CO2 helped to extend the marketability till 9 days storage at 8 °C. The microbiological quality was at the best level up to 6 days of storage, as evidenced by a surge in aerobic plate count, pectinolysers and pseudomonads on subsequent days. Head space volatile analysis of the produce at regular intervals showed a reduction in monoterpenoids and simultaneous increase of aldehydes and ketones, sesquiterpenoids, esters, furans and pyrazines during storage. Principal component analysis of the head space volatiles identified, cis - ocimene, 1,3,8-paramenthatriene, trans 3- caren 2-ol, bergamotene, 2-hexenal, ethyl 1- decanol, (E)-3- hexenol and heptane thiol as the markers of freshness in minimally processed green bell pepper. PMID:26604359

  3. Urine odor

    MedlinePlus

    Urine odor refers to the smell from your urine. Urine odor varies. Most of the time, urine does not ... Most changes in urine odor are not a sign of disease and go away in time. Some foods and medicines, including vitamins, may affect your ...

  4. Differences in the volatile components and their odor characteristics of green and ripe fruits and dried pericarp of Japanese pepper (Xanthoxylum piperitum DC.).

    PubMed

    Jiang, Lihua; Kubota, Kikue

    2004-06-30

    The essential oils of green and ripe fruits and dried pericarp of Japanese pepper (Xanthoxylum piperitum DC.), which are commonly used in Japanese dishes as spices, were extracted with methanol, followed by adsorption to Porapak Q resin. Their aroma profiles were characterized by a sensory evaluation, and their chemical constituents were investigated by using gas chromatography (GC), gas chromatography-mass spectrometry, and aroma extract dilution analysis. Geraniol, citronellal, linalool, and methyl cinnamate were perceived to be important to the basic flavor of the three samples of Japanese pepper by GC-sniffing at high flavor dilution (FD) factors. Monoterpene hydrocarbons constituting almost 76% of the essential oil are the major flavor compounds in the green fruit, and the stronger green and pine leaf notes in the green fruit were considered to be imparted mainly by the large amount of d-limonene, beta-phellandrene, and myrcene due to their high FD factors. On the other hand, the oxygenated terpenes including citronellal, geraniol, and geranial are predominant for the potent odorant in the ripe fruit. The marked citrus-like note in the ripe fruit was thought to be due to the amounts of geranial and citronellal, being 20% of the essential oil. In the dried pericarp, the ratio of oxygenated terpenoids was almost equal to that of monoterpene hydrocarbons. These seemed to induce the flavor character of the dried pericarp to be milder than that of the ripe fruit. PMID:15212469

  5. Assessing the Culture of Fresh Produce Safety within a Leafy Green Producing Community

    ERIC Educational Resources Information Center

    Nolte, Kurt D.; Sanchez, Charles A.; Fonseca, Jorge M.

    2011-01-01

    The 2006 "Escherichia coli" outbreak in spinach prompted the implementation of unprecedented production strategies (Arizona Leafy Green Products Shipper Marketing Agreement) to minimize microbial risk in leafy greens. As the new procedures require assessments of physical intrusion and excrement in fields, outreach was initiated to educate adult…

  6. Fresh and preserved green fodder modify effects of urinary acidifiers on urine pH of horses.

    PubMed

    Goren, G; Fritz, J; Dillitzer, N; Hipp, B; Kienzle, E

    2014-04-01

    Hay stabilises urine pH in horses. It is unknown whether this is an effect of structure or of chemical composition. In this study, four ponies (230-384 kg body weight [BW]) were fed six different diets with either a structure or a composition similar to hay with and without acidifiers in a cross-over experimental design in amounts to maintain body weight with the following main compounds: Fresh grass (GRASS), alfalfa hay (ALF), grass cobs (COBS), grass silage (SIL), straw (STR) or extruded straw (STRe) for 2 to 10 days. Urine pH was measured in all trials, blood pH, blood base excess and bicarbonate as well as mineral balance were determined in GRASS, ALF, STR and STRe. In the trials with straw and extruded straw, urine pH decreased significantly (STR control: 7.8 ± 0.23, acidifier: 5.2 ± 0.38) when acidifiers were added, whereas in all other diets that were based on fresh or preserved green fodder, pH did not decrease below 7. Blood pH was similarly affected by diet and acidifiers. Acidifiers had little effect on the pre-prandial blood pH, only in diet STR there was a significant reduction in relation to control. Post-prandial blood pH was significantly reduced by acidifiers in all diets. Blood bicarbonate and base excess showed corresponding effects. Faecal and renal mineral excretion and apparent mineral digestibility were not systematically affected by diet or acidifiers except for chloride. Chloride added as inorganic chloride salt had an even better apparent digestibility than chloride originating from feed. Because only green plant material stabilised acid base balance, chlorophyll and its metabolites are discussed as potential mediators of the effect of green fodder on acid base balance. PMID:23551706

  7. K and Ca content of fresh green tea, black tea, and tea residue determined by X-ray fluorescence analysis.

    PubMed

    Nas, S; Gokalp, H Y; Sahin, Y

    1993-01-01

    X-Ray fluorescence (XRF) can be successfully used for the qualitative and quantitative elemental analysis of various agricultural products. Its simplicity, high throughput and the possibility of automation make it useful for screening large numbers of samples. The K and Ca content of 138 samples of fresh green tea, black tea and black tea residues were determined by applying the XRF system. Such a method of mineral analysis of food products is not very common. Tea from different tea-growing areas of Turkey, green tea of different shooting periods, black tea processed at different tea plants and tea residues from these black tea were analysed. The K content of green tea, processed black tea and tea residues after brewing were found to have ranges of 19,049-26,254 mg/kg, 21,904-26,883 mg/kg and 9,468-13,778 mg/kg, respectively. In the same samples the Ca content was determined as 3,580-4,799 mg/kg, 3,370-4,823 mg/kg, and 3,743-5,733 mg/kg, respectively. These findings were compared with the results of atomic emission techniques and it was concluded that the XRF system could be effectively used for quantitative analysis of the K and Ca content of tea samples. PMID:8438623

  8. Modeling indoor odor-odorant concentrations and the relative humidity effect on odor perception at a water reclamation plant

    NASA Astrophysics Data System (ADS)

    Wang, Tingting; Sattayatewa, Chakkrid; Venkatesan, Dhesikan; Noll, Kenneth E.; Pagilla, Krishna R.; Moschandreas, Demetrios J.

    2011-12-01

    Models formulated to associate odors and odorants in many industrial and agricultural fields ignore the potential effect of relative humidity on odor perception, and are not validated. This study addresses literature limitations by formulating a model that includes relative humidity and by validating the model. The model employs measured paired values, n = 102, of indoor odors and odorants from freshly dewatered biosolids in a post-digestion dewatering building of a Water Reclamation Plant (WRP). A random sub-sample of n = 32 is used to validate the model by associating predicted vs. measured values ( R2 = 0.90). The model is validated again with a smaller independent database from a second WRP ( R2 = 0.85). Moreover this study asserts that reduction of hydrogen sulfide concentrations, conventionally used as a surrogate of sewage odors, to acceptable levels does not assure acceptable odor levels. It is concluded that: (1) The addition of relative humidity results in a stronger association between odors and odorants than the use of H 2S alone; (2) the two step model validation indicates that the model is not simply site-specific but can be applied to similar facilities; and (3) the model is a promising tool for designing odor and odorant control strategies, the ultimate goal of engineering studies.

  9. Breath odor

    MedlinePlus

    ... tube) in place. The breath may have an ammonia-like odor (also described as urine-like or " ... kidney failure (can cause breath to smell like ammonia ) Diabetes (fruity or sweet chemical smell associated with ...

  10. Structure-Odor Relationships of (E)-3-Alkenoic Acids, (E)-3-Alken-1-ols, and (E)-3-Alkenals.

    PubMed

    Lorber, Katja; Buettner, Andrea

    2015-08-01

    (E)-3-Unsaturated volatile acids, alcohols, and aldehydes are commonly found as odorants or pheromones in foods and other natural sources, playing a vital role in not only the attractiveness of foods but also chemo-communication in the animal kingdom. However, a systematic elucidation of their aroma properties, especially for humans, has not been carried out until today. To close this gap, the odor thresholds in air and odor qualities of homologous series of (E)-3-alkenoic acids, (E)-3-alken-1-ols, and (E)-3-alkenals were determined by gas chromatography-olfactometry. In the series of (E)-3-alkenoic acids the odor quality changed successively from sweaty via plastic-like to sweaty and waxy. On the other hand, the odor qualities in the series of (E)-3-alken-1-ols and (E)-3-alkenals changed from grassy, green to an overall citrus-like, fresh, soapy, and coriander-like odor with increasing chain length. With regard to their odor potencies, the lowest thresholds in air were found for (E)-3-heptenoic acid, (E)-3-hexenoic acid, and (E)-3-hexenal. PMID:26165743

  11. Survival and distribution of Escherichia coli on diverse fresh-cut baby leafy greens under preharvest through postharvest conditions.

    PubMed

    Tomás-Callejas, Alejandro; López-Velasco, Gabriela; Camacho, Alex B; Artés, Francisco; Artés-Hernández, Francisco; Suslow, Trevor V

    2011-12-01

    Escherichia coli O157:H7 has been associated in multiple outbreaks linked to the consumption of whole produce and fresh-cut leafy vegetables. However, plant-based foods had not been traditionally recognized as a host for enteric pathogens until the elevated incidence of produce-related outbreaks became apparent. The survival dynamics of two cocktails of generic E. coli (environmental water, plant and soil isolates) and E. coli O157:H7 within the phyllosphere of Mizuna, Red Chard and Tatsoi during their production, harvest, minimal processing, packaging and storage over two greenhouse production cycles were studied. Genotyping of applied generic E. coli strains to evaluate their comparative survival and relative abundance in the phyllosphere by REP-PCR is also reported. The Mizuna, Red Chard and Tatsoi shoots were grown under standard greenhouse conditions and fertility management. Both E. coli cocktails were spray-inoculated separately and determined to result in an initial mean population density of log 4.2 CFU/cm². Leaves were harvested as mini-greens approximating commercial maturity, minimally processed in a model washing system treated with 3 mg/L of ClO₂ and stored for 7 days at 5 °C. Rapid decline of generic E. coli and E. coli O157:H7 populations was observed for all plant types regardless of the leaf age at the time of inoculation and the irrigation type across both seasonal growth cycle trials. The decline rate of the surviving populations for the fall season was slower than for the summer season. The minimal processing with 3 mg/L of ClO₂ was not sufficient to fully disinfect the inoculated leaves prior to packaging and refrigerated storage. Viable populations of E. coli and E. coli O157:H7 were confirmed throughout storage, including the final time point at the end of acceptable visual leaf quality. In this study, the ability of low populations of E. coli to survive during production and postharvest operations in selected mini-greens has been

  12. Odor Mortis

    SciTech Connect

    Vass, Arpad Alexander

    2012-01-01

    This study, the third of a series on the odor signature of human decomposition, reports on the intermittent nature of chemical evolution from decomposing human remains, and focuses primarily on headspace analysis from soil associated with older human remains (10-60+ years) from different environments around the globe. Fifty grams of soil were collected in 40mL glass vials with polypropylene sealed lids from soil above known or suspected graves and from subsurface chemical plumes associated with human decompositional events. One hundred eighty six separate samples were analyzed using gas chromatography-mass spectrometry (GC-MS). After comparison to relevant soil controls, approximately fifty volatile chemical compounds were identified as being associated with human remains. This manuscript reports these findings and identifies when and where they are most likely to be detected showing an overall decrease in cyclic and halogenated compounds and an increase in aldehydes and alkanes as time progresses. This research identifies the 'odor signatures' unique to the decomposition of human remains with projected ramifications on cadaver dog training procedures and in the development of field portable analytical instruments which can be used to locate human remains in shallow burial sites.

  13. Rose odor can innately counteract predator odor.

    PubMed

    Matsukawa, Mutsumi; Imada, Masato; Murakami, Toyotaka; Aizawa, Shin; Sato, Takaaki

    2011-03-24

    When animals smell a predator odor such as 2,5-Dihydro-2,4,5-trimethylthiazoline (TMT), even if it is a novel substance, the hypothalamo-pituitary-adrenal (HPA) axis is activated, causing stress-like behaviors. Although the medial part of the bed nucleus of stria terminalis (mBST) is known to be involved in this process, the mechanism remains unclear. Moreover, it is unknown whether there is any odor that can counteract the predator odor, even when the odorants are novel substances for the animals. In this study, we assessed whether rose odor can counteract by counting the number of activated neurons in mice brain following the presentation of rose odor with or without TMT for 30 min. The number of activated cells in the mBST and in the ventrorostral part of the anterior piriform cortex (APC) was significantly reduced by a mixture of TMT and rose odor; however, no significant differences were noted in the dorsal part of the APC and in the olfactory bulb (OB) following TMT presentation with or without rose odor. The results suggest that rose odor may counteract the TMT-induced stress response in the OB and/or APC and suppress the neural circuit to the mBST. It also indicates that there are some odors that can innately counteract predator odor, even when they have not been experienced before. PMID:21266167

  14. Effect of predator odors on heart rate and metabolic rate of wapiti (Cervus elaphus canadensis).

    PubMed

    Chabot, D; Gagnon, P; Dixon, E A

    1996-04-01

    We measured the heart rate (HR) and oxygen consumption ([Formula: see text]) of wapiti (Cervus elaphus canadensis) before, during, and after presentation of biologically irrelevant odors (pentane, thiophene, and a perfume), artificial predator odors (an ether extract of cougar feces, and PDT, a compound found in mustelid anal gland secretion), stale predator odors (dog feces and urine and fox urine, kept at ambient temperature for a few weeks), and fresh predator odors (wolf, coyote, and cougar feces and the odor of a dead coyote, kept frozen between collection and test). Overall, responses to odors were small compared to other stressful stimuli. Individual variability was high among scents and among wapiti, but two of the fresh predator odors (cougar and wolf feces) produced larger HR and[Formula: see text] responses than the other scents and were more often successful at producing responses. As a group, fresh predator odors produced larger tachycardias and elicited a larger number of significant HR responses than biologically irrelevant novel odors. although the two classes of odors did not differ in their effect on[Formula: see text]. Although several other studies have shown that ungulates have reduced feeding levels when their food is scented with predator odors, it is not clear if this is due to reduced palatability or antipredator behavior. This study is the first demonstration that a wild ungulate species reacted more strongly to predator odors than to other odors in a nonfeeding situation. PMID:24227589

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

    PubMed

    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. PMID:16891352

  16. Diagnostic odor recognition

    PubMed

    Rosenblatt; Phan; Desandre; Lobon; Hsu

    2000-10-01

    Many diseases, toxic ingestions, and intoxications have characteristic odors. These odors may provide diagnostic clues that affect rapid treatment long before laboratory confirmation or clinical deterioration. Odor recognition skills, similar to auscultation and palpation skills, require teaching and practical exposure. Dr. Goldfrank and colleagues recognized the importance of teaching odor recognition to emergency service providers. They proposed the "sniffing bar" method for odor recognition training. OBJECTIVES: (1) To identify the recognition rates of medically important odors among emergency care providers. (2) To investigate the effectiveness of teaching odor recognition. Hypothesis: The recognition rates of medically important odors will increase after teaching exposure. METHODS: The study exposed emergency care providers to 11 tubes of odors. Identifications of each substance were recorded. After corrective feedback, subjects were re-tested on their ability to identify the odors. Analysis of odor recognition improvement after teaching was done via chi-square test. RESULTS: Improvement in identification after teaching was seen in all odors. However, the improvement was significant only in the lesscommon substances because their initial recognition was especially low. Significant changes may improve with a larger sample size. Subjects often confuse the odors of alcohol with acetone, and wintergreen with camphor. CONCLUSIONS: The recognition rates are higher for the more-common odors, and lower for the less-common odors. Teaching exposures to the less well-known odors are effective and can significantly improve the recognition rate of these substances. Because odor recognition may affect rapid diagnosis and treatment of certain medical emergencies such as toxic ingestion, future studies should investigate the correlation between odor recognition and the ability to identify corresponding medical emergencies. PMID:11015270

  17. Predicting Odor Perceptual Similarity from Odor Structure

    PubMed Central

    Weiss, Tali; Frumin, Idan; Khan, Rehan M.; Sobel, Noam

    2013-01-01

    To understand the brain mechanisms of olfaction we must understand the rules that govern the link between odorant structure and odorant perception. Natural odors are in fact mixtures made of many molecules, and there is currently no method to look at the molecular structure of such odorant-mixtures and predict their smell. In three separate experiments, we asked 139 subjects to rate the pairwise perceptual similarity of 64 odorant-mixtures ranging in size from 4 to 43 mono-molecular components. We then tested alternative models to link odorant-mixture structure to odorant-mixture perceptual similarity. Whereas a model that considered each mono-molecular component of a mixture separately provided a poor prediction of mixture similarity, a model that represented the mixture as a single structural vector provided consistent correlations between predicted and actual perceptual similarity (r≥0.49, p<0.001). An optimized version of this model yielded a correlation of r = 0.85 (p<0.001) between predicted and actual mixture similarity. In other words, we developed an algorithm that can look at the molecular structure of two novel odorant-mixtures, and predict their ensuing perceptual similarity. That this goal was attained using a model that considers the mixtures as a single vector is consistent with a synthetic rather than analytical brain processing mechanism in olfaction. PMID:24068899

  18. Immunization alters body odor.

    PubMed

    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. PMID:24524972

  19. Influence of Vacuum Cooling on Escherichia coli O157:H7 Infiltration in Fresh Leafy Greens via a Multiphoton-Imaging Approach

    PubMed Central

    Vonasek, Erica

    2015-01-01

    Microbial pathogen infiltration in fresh leafy greens is a significant food safety risk factor. In various postharvest operations, vacuum cooling is a critical process for maintaining the quality of fresh produce. The overall goal of this study was to evaluate the risk of vacuum cooling-induced infiltration of Escherichia coli O157:H7 into lettuce using multiphoton microscopy. Multiphoton imaging was chosen as the method to locate E. coli O157:H7 within an intact lettuce leaf due to its high spatial resolution, low background fluorescence, and near-infrared (NIR) excitation source compared to those of conventional confocal microscopy. The variables vacuum cooling, surface moisture, and leaf side were evaluated in a three-way factorial study with E. coli O157:H7 on lettuce. A total of 188 image stacks were collected. The images were analyzed for E. coli O157:H7 association with stomata and E. coli O157:H7 infiltration. The quantitative imaging data were statistically analyzed using analysis of variance (ANOVA). The results indicate that the low-moisture condition led to an increased risk of microbial association with stomata (P < 0.05). Additionally, the interaction between vacuum cooling levels and moisture levels led to an increased risk of infiltration (P < 0.05). This study also demonstrates the potential of multiphoton imaging for improving sensitivity and resolution of imaging-based measurements of microbial interactions with intact leaf structures, including infiltration. PMID:26475109

  20. Lowered Risk of Nasopharyngeal Carcinoma and Intake of Plant Vitamin, Fresh Fish, Green Tea and Coffee: A Case-Control Study in Taiwan

    PubMed Central

    Hsu, Wan-Lun; Pan, Wen-Harn; Chien, Yin-Chu; Yu, Kelly J.; Cheng, Yu-Juen; Chen, Jen-Yang; Liu, Mei-Ying; Hsu, Mow-Ming; Lou, Pei-Jen; Chen, I-How; Yang, Czau-Siung; Hildesheim, Allan; Chen, Chien-Jen

    2012-01-01

    Background A case-control study was conducted to evaluate the role of adult diet on nasopharyngeal carcinoma (NPC) in Taiwan. Methods A total of 375 incident NPC cases and 327 controls matched to the cases on sex, age, and residence were recruited between July 1991 and December 1994. A structured questionnaire inquiring complete dietary history, socio-demographic characteristics, and other potential confounding factors was used in the personal interview. Unconditional logistic regression analysis was used to estimate multivariate-adjusted odds ratio (ORadj) with 95% confidence interval (CI) after accounting for known risk factors. Results Fresh fish (ORadj, 0.56; 95% CI, 0.38–0.83 for the highest vs. lowest tertile of intake), green tea (ORadj, 0.61; 95% CI, 0.40–0.91 for drinking ≥1 times/week vs. never) and coffee (ORadj, 0.56; 95% CI, 0.37–0.85 for drinking ≥0.5 times/week vs. never) were inversely associated with the NPC risk. No association with NPC risk was observed for the intake of meats, salted fish, fresh vegetables, fruits and milk. Intake of vitamin A from plant sources was associated with a decreased NPC risk (ORadj, 0.62; 95% CI, 0.41–0.94 for the highest vs. lowest tertile). Conclusion The study findings suggest that certain adult dietary patterns might protect against the development of NPC. PMID:22848600

  1. Characterizing odors from cattle feedlots with different odor techniques

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Odors from cattle feedlots negatively affect local communities. The purpose of this study was to characterize odors and odorants using different odor sampling techniques. Odors were characterized with field olfactometers (Nasal Ranger®), sensory techniques (GC-O) and analytical techniques (sorbent t...

  2. Quantitative transfer of Escherichia coli O157:H7 to equipment during small-scale production of fresh-cut leafy greens.

    PubMed

    Buchholz, Annemarie L; Davidson, Gordon R; Marks, Bradley P; Todd, Ewen C D; Ryser, Elliot T

    2012-07-01

    Postharvest contamination and subsequent spread of Escherichia coli O157:H7 can occur during shredding, conveying, fluming, and dewatering of fresh-cut leafy greens. This study quantified E. coli O157:H7 transfer from leafy greens to equipment surfaces during simulated small-scale commercial processing. Three to five batches (22.7 kg) of baby spinach, iceberg lettuce, and romaine lettuce were dip inoculated with a four-strain cocktail of avirulent, green fluorescent protein-labeled, ampicillinresistant E. coli O157:H7 to contain ∼10(6), 10(4), and 10(2) CFU/g, and then were processed after 1 h of draining at ∼23°C or 24 h of storage at 4°C. Lettuce was shredded using an Urschel TransSlicer at two different blade and belt speeds to obtain normal (5 by 5 cm) and more finely shredded (0.5 by 5 cm) lettuce. Thereafter, the lettuce was step conveyed to a flume tank and was washed and then dried using a shaker table and centrifugal dryer. Product (25-g) and water (40-ml) samples were collected at various points during processing. After processing, product contact surfaces (100 cm(2)) on the shredder (n = 14), conveyer (n = 8), flume tank (n = 11), shaker table (n = 9), and centrifugal dryer (n = 8) were sampled using one-ply composite tissues. Sample homogenates diluted in phosphate or neutralizing buffer were plated, with or without prior 0.45- m m membrane filtration, on Trypticase soy agar containing 0.6% yeast extract supplemented with 100 ppm of ampicillin to quantify green fluorescent protein-labeled E. coli O157:H7 under UV light. During leafy green processing, ∼90% of the E. coli O157:H7 inoculum transferred to the wash water. After processing, E. coli O157:H7 populations were highest on the conveyor and shredder (P<0.05), followed by the centrifugal dryer, flume tank, and shaker table, with ∼29% of the remaining product inoculum lost during centrifugal drying. Overall, less (P<0.05) of the inoculum remained on the product after centrifugally drying

  3. Assessing the status of food safety management systems for fresh produce production in East Africa: evidence from certified green bean farms in Kenya and noncertified hot pepper farms in Uganda.

    PubMed

    Nanyunja, J; Jacxsens, L; Kirezieva, K; Kaaya, A N; Uyttendaele, M; Luning, P A

    2015-06-01

    The farms of fresh produce farmers are major sources of food contamination by microbiological organisms and chemical pesticides. In view of their choice for farming practices, producers are influenced by food safety requirements. This study analyzes the role of food safety standard certification toward the maturity of food safety management systems (FSMS) in the primary production of fresh produce. Kenya and Uganda are two East African countries that export green beans and hot peppers, respectively, to the European Union but have contrasting features in terms of agricultural practices and certification status. In the fresh produce chain, a diagnostic instrument for primary production was used to assess context factors, core control and assurance activities, and system output to measure the performance of FSMS for certified green bean farms in Kenya and noncertified hot pepper farms in Uganda. Overall, our findings show that in Uganda, noncertified hot pepper farms revealed only a "basic level of control and assurance" activities in their FSMS, which was not satisfactory, because no insight into potential pesticide microbial contamination was presented by these farmers. On the other hand, certified green bean farms in Kenya had an "average level of control and assurance," providing insight into the delivered food safety and quality by the farmers. Farm size did not impact the maturity level of FSMS. This study confirms the role played by food safety standard certification toward the maturity of FSMS implemented in developing countries and demonstrates the possibility of Ugandan farms to upgrade agricultural practices in the fresh produce sector. PMID:26038896

  4. Odor Control Technology

    ERIC Educational Resources Information Center

    Turk, Amos; And Others

    1972-01-01

    Dispersion, chemical oxidation, and masking are reviewed as techniques primarily employed for odor control. Devices and systems, costs, and problems of measurement are considered in light of environmental agencies' efforts to curb smelly emissions. (BL)

  5. Tracking an Escherichia coli O157:H7-contaminated batch of leafy greens through a pilot-scale fresh-cut processing line.

    PubMed

    Buchholz, Annemarie L; Davidson, Gordon R; Marks, Bradley P; Todd, Ewen C D; Ryser, Elliot T

    2014-09-01

    Cross-contamination of fresh-cut leafy greens with residual Escherichia coli O157:H7-contaminated product during commercial processing was likely a contributing factor in several recent multistate outbreaks. Consequently, radicchio was used as a visual marker to track the spread of the contaminated product to iceberg lettuce in a pilot-scale processing line that included a commercial shredder, step conveyor, flume tank, shaker table, and centrifugal dryer. Uninoculated iceberg lettuce (45 kg) was processed, followed by 9.1 kg of radicchio (dip inoculated to contain a four-strain, green fluorescent protein-labeled nontoxigenic E. coli O157:H7 cocktail at 10(6) CFU/g) and 907 kg (2,000 lb) of uninoculated iceberg lettuce. After collecting the lettuce and radicchio in about 40 bags (∼22.7 kg per bag) along with water and equipment surface samples, all visible shreds of radicchio were retrieved from the bags of shredded product, the equipment, and the floor. E. coli O157:H7 populations were quantified in the lettuce, water, and equipment samples by direct plating with or without prior membrane filtration on Trypticase soy agar containing 0.6% yeast extract and 100 ppm of ampicillin. Based on triplicate experiments, the weight of radicchio in the shredded lettuce averaged 614.9 g (93.6%), 6.9 g (1.3%), 5.0 g (0.8%), and 2.8 g (0.5%) for bags 1 to 10, 11 to 20, 21 to 30, and 31 to 40, respectively, with mean E. coli O157:H7 populations of 1.7, 1.2, 1.1, and 1.1 log CFU/g in radicchio-free lettuce. After processing, more radicchio remained on the conveyor (9.8 g; P < 0.05), compared with the shredder (8.3 g), flume tank (3.5 g), and shaker table (0.1 g), with similar E. coli O157:H7 populations (P > 0.05) recovered from all equipment surfaces after processing. These findings clearly demonstrate both the potential for the continuous spread of contaminated lettuce to multiple batches of product during processing and the need for improved equipment designs that minimize

  6. Odor coding in a disease-transmitting herbivorous insect, the Asian citrus psyllid.

    PubMed

    Coutinho-Abreu, Iliano V; McInally, Shane; Forster, Lisa; Luck, Robert; Ray, Anandasankar

    2014-07-01

    Olfactory systems discriminate odorants very efficiently and herbivorous insects use them to find hosts in confounding and complex odor landscapes. The Asian citrus psyllid (ACP), Diaphorina citri, feeds on citrus flush and transmits Candidatus Liberibacter that causes citrus greening disease globally. Here, we perform a systematic analysis of odor detection in the ACP antenna using single-unit electrophysiology of rhinarial plate sensilla to a large panel of odorants from plants. We identify neurons that respond strongly to odorants found in the host citrus plants. Comparisons with the generalist yeast-feeding Drosophila melanogaster and specialist anthropophilic Anopheles gambiae reveal differences in odor-coding strategies for the citrus-seeking ACP. These findings provide a foundation for understanding host-odor coding in herbivorous insects. PMID:24904081

  7. Physics of Fresh Produce Safety: Role of Diffusion and Tissue Reaction in Sanitization of Leafy Green Vegetables with Liquid and Gaseous Ozone-Based Sanitizers.

    PubMed

    Shynkaryk, Mykola V; Pyatkovskyy, Taras; Mohamed, Hussein M; Yousef, Ahmed E; Sastry, Sudhir K

    2015-12-01

    Produce safety has received much recent attention, with the emphasis being largely on discovery of how microbes invade produce. However, the sanitization operation deserves more attention than it has received. The ability of a sanitizer to reach the site of pathogens is a fundamental prerequisite for efficacy. This work addresses the transport processes of ozone (gaseous and liquid) sanitizer for decontamination of leafy greens. The liquid sanitizer was ineffective against Escherichia coli K-12 in situations where air bubbles may be trapped within cavities. A model was developed for diffusion of sanitizer into the interior of produce. The reaction rate of ozone with the surface of a lettuce leaf was determined experimentally and was used in a numerical simulation to evaluate ozone concentrations within the produce and to determine the time required to reach different locations. For aqueous ozone, the penetration depth was limited to several millimeters by ozone self-decomposition due to the significant time required for diffusion. In contrast, gaseous sanitizer was able to reach a depth of 100 mm in several minutes without depletion in the absence of reaction with surfaces. However, when the ozone gas reacted with the produce surface, gas concentration was significantly affected. Simulation data were validated experimentally by measuring ozone concentrations at the bottom of a cylinder made of lettuce leaf. The microbiological test confirmed the relationship between ozone transport, its self-decomposition, reaction with surrounding materials, and the degree of inactivation of E. coli K-12. Our study shows that decontamination of fresh produce, through direct contact with the sanitizer, is more feasible with gaseous than with aqueous sanitizers. Therefore, sanitization during a high-speed washing process is effective only for decontaminating the wash water. PMID:26613904

  8. Effect of dynamic temperature storage in retail display case on the quality and microbiota of packaged fresh-cut leafy greens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Commercial refrigeration equipment is projected to rise 5.2% annually to meet the consumer demand for fresh-cut produce items. The highly variable temperature conditions associated with storage of fresh-cuts in commercial open-refrigerated display cases dramatically affects the shelf-life and qualit...

  9. Suppression of Odorant Responses by Odorants in Olfactory Receptor Cells

    NASA Astrophysics Data System (ADS)

    Kurahashi, Takashi; Lowe, Graeme; Gold, Geoffrey H.

    1994-07-01

    Odorants activate an inward current in vertebrate olfactory receptor cells. Here it is shown, in receptor cells from the newt, that odorants can also suppress this current, by a mechanism that is distinct from inhibition and adaptation. Suppression provides a simple explanation for two seemingly unrelated phenomena: the anomalously long latency of olfactory transduction and the existence of an "off response" at the end of a prolonged stimulus. Suppression may influence the perception of odorants by masking odorant responses and by sharpening the odorant specificities of single cells.

  10. Children's hedonic judgments of cigarette smoke odor: effects of parental smoking and maternal mood.

    PubMed

    Forestell, Catherine A; Mennella, Julie A

    2005-12-01

    Age-appropriate tasks were used to assess 3- to 8-year-old children's liking, identification, and preference for a variety of odors, including that of exhaled cigarette smoke. Children whose parents smoke took longer to decide whether they liked the cigarette odor and were significantly more likely to prefer the odor of cigarette to the neutral and unfamiliar odor of green tea compared with children of nonsmokers. Among children of smokers, relative preferences for the cigarette odor were related to maternal mood disturbance and depression scores. These findings suggest that some early learning about cigarette smoke odor is based on sensory experiences at home and anchors it to the emotional context in which their mothers smoke. PMID:16366814

  11. Children’s Hedonic Judgments of Cigarette Smoke Odor: Effects of Parental Smoking and Maternal Mood

    PubMed Central

    Forestell, Catherine A.; Monell, Julie A. Mennella

    2006-01-01

    Age-appropriate tasks were used to assess 3-to 8-year-old children’s liking, identification, and preference for a variety of odors, including that of exhaled cigarette smoke. Children whose parents smoke took longer to decide whether they liked the cigarette odor and were significantly more likely to prefer the odor of cigarette to the neutral and unfamiliar odor of green tea compared with children of nonsmokers. Among children of smokers, relative preferences for the cigarette odor were related to maternal mood disturbance and depression scores. These findings suggest that some early learning about cigarette smoke odor is based on sensory experiences at home and anchors it to the emotional context in which their mothers smoke. PMID:16366814

  12. Suppression of Background Odor Effect in Odor Sensing System Using Olfactory Adaptation Model

    NASA Astrophysics Data System (ADS)

    Ohba, Tsuneaki; Yamanaka, Takao

    In this study, a new method for suppressing the background odor effect is proposed. Since odor sensors response to background odors in addition to a target odor, it is difficult to detect the target odor information. In the conventional odor sensing systems, the effect of the background odors are compensated by subtracting the response to the background odors (the baseline response). Although this simple subtraction method is effective for constant background odors, it fails in the compensation for time-varying background odors. The proposed method for the background suppression is effective even for the time-varying background odors.

  13. Health effects of indoor odorants.

    PubMed

    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. PMID:1821378

  14. Health effects of indoor odorants.

    PubMed Central

    Cone, J E; Shusterman, D

    1991-01-01

    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. PMID:1821378

  15. Striving for safety in fresh and fresh-cut fruits and vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consumption of fresh produce is a central component of a healthy diet. However, contamination of leafy greens, tomatoes, cantaloupes and other fresh and fresh-cut fruits and vegetables with human pathogens is a source of ongoing concern for consumers. Industry and regulators have worked together to ...

  16. Distant Odors: Identifying Key Odors Associated With Cattle Feedlots Downwind

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The National Research Council identified odors as the most significant animal emission at the local level and has highlighted the need for the development of standardized protocols for sampling and analysis of odors. To date, however, little progress has been made on identifying sampling and analys...

  17. Swine odor analyzed by odor panels and chemical techniques

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The National Research Council identified odors as a significant animal emission at the local level, and highlighted the need for the development of standardized protocols for sampling and analysis. In this study, odorous air from swine manure was analyzed by both human panels and with analytical tec...

  18. Odor from a chemical perspective

    SciTech Connect

    Wray, T.K.

    1995-06-01

    Early odor-detection measurements categorized chemicals according to odor quality. Recent methods focus on the odor threshold, or the quantitative amount of a chemical in air that can be detected by the human sense of smell. Researchers characterize and quantify odor using an array of sensory and analytical procedures. Humans possess one of the dullest mammalian senses of smell; however, they can recognize about 10,000 distinct odors at concentrations ranging from less than 1 part per billion to several hundred thousand parts per million. Each time humans inhale, they chemically analyze microscopic pieces of the environment that make physical contact with the nerves in their noses. Individual molecules travel up the nose to a sheet of moist, mucus-bathed tissue that consists of about 5 million smell-sensing, olfactory neurons. After dissolving in the mucus, odor molecules ``float`` into appropriately shaped receptor pockets. A series of cellular reactions then transmit impulses to the limbic system, hippocampus and, finally, the neocortex. Odor detection is an important defense mechanism. The author presents the odor thresholds for selected organic compounds, and other hazardous chemicals.

  19. Use of wood-based materials in beef bedded manure packs: 2. Effect on odorous volatile organic compounds, odor activity value, , and nutrient concentrations.

    PubMed

    Spiehs, Mindy J; Brown-Brandl, Tami M; Berry, Elaine D; Wells, James E; Parker, David B; Miller, Daniel N; Jaderborg, Jeffrey P; DiCostanzo, Alfred

    2014-07-01

    The objectives of this study were to determine the effects of three types of wood-based bedding materials (kiln-dried pine wood chips, dry cedar chips, and green cedar chips) and corn stover on the concentration of odorous volatile organic compounds (VOCs) and total in bedded pack material. Four bedded packs of each bedding material were maintained for two 42-d periods ( = 32; eight replicates/bedding material). Straight- and branched-chained fatty acids, aromatic compounds, and sulfide compounds were measured from the headspace above each bedded pack. Green cedar bedding had the highest concentration of odorous VOCs, and pine chip bedding had the lowest ( < 0.01). Calculated odor activity values were highest for green cedar bedding, followed by dry cedar, corn stover, and pine chip bedding. As the bedded packs aged, the concentration of odorous VOCs increased, particularly in the bedded packs containing green cedar chips and dry cedar chips. Total concentrations increased from Days 0 to 21 and then began to decline and were similar among all bedding materials ( < 0.10). Results of this study indicate that producers using a long-term bedded pack management in their facility may benefit from using pine chips because they do not appear to increase odor over time. Cedar-based bedding materials may be better suited for a scrape-and-haul system, where the bedded pack is removed after 1 or 2 wk. Total concentrations did not differ between any of the four bedding materials over time. PMID:25603068

  20. Odor and odorous chemical emissions from animal buildings: Part 2. Odor emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was an add-on project to the National Air Emissions Monitoring Study (NAEMS) and focused on comprehensive measurement of odor emissions considering variations in seasons, animal types and olfactometry laboratories. Odor emissions from four of 14 NEAMS sites with nine barns/rooms (two dair...

  1. Odor and odorous chemical emissions from animal buildings: Part 6.Odor activity value

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is a growing concern with air and odor emissions from agricultural facilities. A supplementary research project was conducted to complement the U.S. National Air Emissions Monitoring Study (NAEMS). The overall goal of the project was to establish odor and chemical emission factors for animal...

  2. Odor and odorous chemical emissions from animal buildings: Part 2 - odor emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was an add-on project to the National Air Emissions Monitoring Study (NAEMS) and focused on comprehensive measurement of odor emissions. Odor emissions from two animal species (dairy and swine) from four sites with nine barns/rooms (two dairy barns in Wisconsin, two dairy barns and two sw...

  3. A Green Preconcentration Method for Determination of Cobalt and Lead in Fresh Surface and Waste Water Samples Prior to Flame Atomic Absorption Spectrometry

    PubMed Central

    Naeemullah; Kazi, Tasneem Gul; Shah, Faheem; Afridi, Hassan Imran; Khan, Sumaira; Arian, Sadaf Sadia; Brahman, Kapil Dev

    2012-01-01

    Cloud point extraction (CPE) has been used for the preconcentration and simultaneous determination of cobalt (Co) and lead (Pb) in fresh and wastewater samples. The extraction of analytes from aqueous samples was performed in the presence of 8-hydroxyquinoline (oxine) as a chelating agent and Triton X-114 as a nonionic surfactant. Experiments were conducted to assess the effect of different chemical variables such as pH, amounts of reagents (oxine and Triton X-114), temperature, incubation time, and sample volume. After phase separation, based on the cloud point, the surfactant-rich phase was diluted with acidic ethanol prior to its analysis by the flame atomic absorption spectrometry (FAAS). The enhancement factors 70 and 50 with detection limits of 0.26 μg L−1 and 0.44 μg L−1 were obtained for Co and Pb, respectively. In order to validate the developed method, a certified reference material (SRM 1643e) was analyzed and the determined values obtained were in a good agreement with the certified values. The proposed method was applied successfully to the determination of Co and Pb in a fresh surface and waste water sample. PMID:23227429

  4. Identification of sulphur volatiles and GC-olfactometry aroma profiling in two fresh tomato cultivars.

    PubMed

    Du, Xiaofen; Song, Mei; Baldwin, Elizabeth; Rouseff, Russell

    2015-03-15

    Ten sulphur volatiles were observed in two Florida tomato cultivars ('Tasti-Lee' and 'FL 47') harvested at three maturity stages (breaker, turning, and pink) using gas chromatography with a pulsed flame photometric detector (GC-PFPD). Eight PFPD peaks were identified using retention values from authentic sulphur standards and GC-MS characteristic masses. Seven were quantified using an internal standard combined with external calibration curves. Dimethyl sulphide, dimethyl disulphide, dimethyl trisulphide 2-propylthiazole and 2-s-butylthiazole were newly identified in fresh tomatoes. Principal component analysis of sulphur volatiles indicated that there were appreciable maturity stage differences clustered in separate quadrants. GC-olfactometry (GC-O) identified 50 aroma-active compounds in 'Tasti-Lee', with 10 reported as odorants in fresh tomatoes for the first time. Four sulphur volatiles exhibited aroma activity, including two of the newly-reported fresh tomato sulphur volatiles, 2-s-butylthiazole and dimethyl sulphide. GC-O aroma profiling indicated that the most intense aroma category was earthy-musty, followed by fruity-floral, green-grassy, sweet-candy and sweaty-stale-sulphurous. PMID:25308674

  5. Transfer of Escherichia coli O157:H7 from equipment surfaces to fresh-cut leafy greens during processing in a model pilot-plant production line with sanitizer-free water.

    PubMed

    Buchholz, Annemarie L; Davidson, Gordon R; Marks, Bradley P; Todd, Ewen C D; Ryser, Elliot T

    2012-11-01

    Escherichia coli O157:H7 contamination of fresh-cut leafy greens has become a public health concern as a result of several large outbreaks. The goal of this study was to generate baseline data for E. coli O157:H7 transfer from product-inoculated equipment surfaces to uninoculated lettuce during pilot-scale processing without a sanitizer. Uninoculated cored heads of iceberg and romaine lettuce (22.7 kg) were processed using a commercial shredder, step conveyor, 3.3-m flume tank with sanitizer-free tap water, shaker table, and centrifugal dryer, followed by 22.7 kg of product that had been dip inoculated to contain ∼10(6), 10(4), or 10(2) CFU/g of a four-strain avirulent, green fluorescent protein-labeled, ampicillin-resistant E. coli O157:H7 cocktail. After draining the flume tank and refilling the holding tank with tap water, 90.8 kg of uninoculated product was similarly processed and collected in ∼5-kg aliquots. After processing, 42 equipment surface samples and 46 iceberg or 36 romaine lettuce samples (25 g each) from the collection baskets were quantitatively examined for E. coli O157:H7 by direct plating or membrane filtration using tryptic soy agar containing 0.6% yeast extract and 100 ppm of ampicillin. Initially, the greatest E. coli O157:H7 transfer was seen from inoculated lettuce to the shredder and conveyor belt, with all equipment surface populations decreasing 90 to 99% after processing 90.8 kg of uncontaminated product. After processing lettuce containing 10(6) or 10(4) E. coli O157:H7 CFU/g followed by uninoculated lettuce, E. coli O157:H7 was quantifiable throughout the entire 90.8 kg of product. At an inoculation level of 10(2) CFU/g, E. coli O157:H7 was consistently detected in the first 21.2 kg of previously uninoculated lettuce at 2 to 3 log CFU/100 g and transferred to 78 kg of product. These baseline E. coli O157:H7 transfer results will help determine the degree of sanitizer efficacy required to better ensure the safety of fresh-cut leafy

  6. Combinatorial effects of odorants on mouse behavior.

    PubMed

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

    2016-06-01

    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

  7. Combinatorial effects of odorants on mouse behavior

    PubMed Central

    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. Characterization of male goat odors: 6-trans nonenal.

    PubMed

    Smith, P W; Parks, O W; Schwartz, D P

    1984-04-01

    Solvent extraction and nitrogen degassing were employed to collect volatile odors from the lipid complex yielded by swabbing the sebaceous gland areas of the scalps of sexually active bucks from four breeds of goats. Gland tissue samples from freshly slaughtered bucks and does also were obtained for lipid analysis. Identified as the major compound responsible for one of the characteristic odors of the buck was 6-trans nonenal . Isolation of the compound as its 2,4-dinitrophenyl hydrazone was achieved by column and thin-layer chromatography. Tentative identification was based on comparison with known compounds by argentation thin-layer chromatography, retardation factors for the 2,4-dinitrophenyl hydrazone derivatives, and gas-liquid chromatography retention times of regenerated compounds. The presence of other nonenals suggests that the compound may be formed by oxidation of the gland lipids. The odor of the male goat in rut often is implicated as a source of the " goaty " flavor problem in fresh goat milk. When added to goat milk, 6-trans nonenal yielded a significant melon- musky flavor response from the flavor panel; the " goaty " flavor response was more significant for added 4-ethyl octanoic acid, 4-methyl octanoic acid, and 4-ethyl oct-2-enoic acid. PMID:6725723

  9. Optical Imaging of Postsynaptic Odor Representation in the Glomerular Layer of the Mouse Olfactory Bulb

    PubMed Central

    Fletcher, Max L.; Masurkar, Arjun V.; Xing, Junling; Imamura, Fumiaki; Xiong, Wenhui; Nagayama, Shin; Mutoh, Hiroki; Greer, Charles A.; Knöpfel, Thomas; Chen, Wei R.

    2009-01-01

    Olfactory glomeruli are the loci where the first odor-representation map emerges. The glomerular layer comprises exquisite local synaptic circuits for the processing of olfactory coding patterns immediately after their emergence. To understand how an odor map is transferred from afferent terminals to postsynaptic dendrites, it is essential to directly monitor the odor-evoked glomerular postsynaptic activity patterns. Here we report the use of a transgenic mouse expressing a Ca2+-sensitive green fluorescence protein (GCaMP2) under a Kv3.1 potassium-channel promoter. Immunostaining revealed that GCaMP2 was specifically expressed in mitral and tufted cells and a subpopulation of juxtaglomerular cells but not in olfactory nerve terminals. Both in vitro and in vivo imaging combined with glutamate receptor pharmacology confirmed that odor maps reported by GCaMP2 were of a postsynaptic origin. These mice thus provided an unprecedented opportunity to analyze the spatial activity pattern reflecting purely postsynaptic olfactory codes. The odor-evoked GCaMP2 signal had both focal and diffuse spatial components. The focalized hot spots corresponded to individually activated glomeruli. In GCaMP2-reported postsynaptic odor maps, different odorants activated distinct but overlapping sets of glomeruli. Increasing odor concentration increased both individual glomerular response amplitude and the total number of activated glomeruli. Furthermore, the GCaMP2 response displayed a fast time course that enabled us to analyze the temporal dynamics of odor maps over consecutive sniff cycles. In summary, with cell-specific targeting of a genetically encoded Ca2+ indicator, we have successfully isolated and characterized an intermediate level of odor representation between olfactory nerve input and principal mitral/tufted cell output. PMID:19474178

  10. Bacterial adhesion to surfaces and microbial safety of fresh produce

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consumption of fresh produce is a central component of a healthy diet. However, contamination of fresh and fresh-cut fruits and vegetables such as leafy greens, tomatoes, cantaloupes is a source of ongoing concern for consumers. Growers, packers, processors and retailers work to control the incidenc...

  11. Use of wood-based materials in beef bedded manure packs: 2. Effect on odorous volatile organic compounds, odor activity value, Escherichia coli, and nutrient concentrations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to determine the effects of three types of wood-based bedding materials (kiln-dried pine wood chips, dry cedar chips, and green cedar chips) and corn stover on concentration of odorous volatile organic compounds (VOC) and total Escherichia coli in bedded pack materi...

  12. Odor and odorous chemical emissions from animal buildings: Part 3. Chemical emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to measure the long-term odor emissions and corresponding concentrations and emissions of 20 odorous volatile organic compounds (VOCs). This study was an add-on study to the National Air Emission Monitoring Study (NAEMS). Odor and odorous gas measurements at four NAEM...

  13. Odor and odorous chemical emissions from animal buildings: Part 3 - chemical emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was an add-on study to the National Air Emission Monitoring Study (NAEMS). The objective of this study was to measure odor emissions and corresponding concentrations and emissions of target odorous gases. Odor and odorous gas measurements at four NAEMS sites (dairy barns in Wisconsin-WI5B...

  14. Rat preference for food-related odors.

    PubMed

    Tabuchi, E; Ono, T; Uwano, T; Takashima, Y; Kawasaki, M

    1991-01-01

    Preferences for food-related odors and the effects of fasting on those preferences were investigated during rat bar pressing for brief odor presentation. A rat was housed in an equilateral octagonal cage and had free access to food and water, except during fasting. Among 8 food-related odor substances (black pepper, cheese, coffee, milk, nut, peppermint, plum and orange), black pepper, milk and coffee were most preferred, and cheese was least preferred, but even the bar pressing rate for cheese was above the operant level. This data indicates that all 8 odors were preferred by rats, although there were different degrees of preference in individual animals. Fasting substantially increased the rate of bar pressing for odors and changed the odors preferences. This result was probably due to increased search for food and water. Since bar pressing was reinforced by nothing other than odor presentation, the results reveal inherent odor preferences of rats. PMID:1959035

  15. Masera's organ responds to odorants.

    PubMed

    Marshall, D A; Maruniak, J A

    1986-02-26

    Electroolfactogram (EOG) recordings from the rat septal olfactory organ (SO) provide the first demonstration of its broad-range chemosensitivity, and clearly establish this structure as a functioning component of the mammalian intranasal chemosensory system. SO sensitivity to lower concentrations of at least one common test odorant (pentyl acetate) exceeds that at sites located on the septal portion of the main olfactory neuroepithelium. Signals from the SO, as first proposed, thus could have an alerting function and provide information relevant to odor stimulus assessment. PMID:3697687

  16. CONTROLLING ODOROUS EMISSIONS FROM IRON FOUNDRIES

    EPA Science Inventory

    The report discusses the control of odorous emissions from iron foundries. he main process sources of odors in iron foundries are mold and core making, casting, and sand shakeout. he odors are usually caused by chemicals, which may be present as binders and other additives to the...

  17. Odor-modulated upwind flight of the sphinx moth, Manduca sexta L.

    PubMed

    Willis, M A; Arbas, E A

    1991-10-01

    1. Male and female Manduca sexta flew upwind in response to the odor of female sex-pheromone gland extract or fresh tobacco leaf respectively, and generated very similar zigzagging tracks along the odor plume. 2. After loss of odor during flight, males and females alike: (1) first flew slower and steered their flight more across the wind, then (2) stopped moving upwind, and finally (3) regressed downwind. 3. Males flying upwind in a pheromone plume in wind of different velocities maintained their ground speed near a relatively constant 'preferred' value by increasing their air speed as the velocity of the wind increased, and also maintained the average angle of their resultant flight tracks with respect to the wind at a preferred value by steering a course more precisely due upwind. 4. The inter-turn duration and turn rate, two measures of the temporal aspects of the flight track, were maintained, on average, with remarkable consistency across all wind velocities and in both sexes. The inter-turn durations also decreased significantly as moths approached the odor source, suggesting modulation of the temporal pattern of turning by some feature of the odor plume. This temporal regularity of turning appears to be one of the most stereotyped features of odor-modulated flight in M. sexta. PMID:1779417

  18. Multivariate prediction of odor from pig production based on in-situ measurement of odorants

    NASA Astrophysics Data System (ADS)

    Hansen, Michael J.; Jonassen, Kristoffer E. N.; Løkke, Mette Marie; Adamsen, Anders Peter S.; Feilberg, Anders

    2016-06-01

    The aim of the present study was to estimate a prediction model for odor from pig production facilities based on measurements of odorants by Proton-Transfer-Reaction Mass spectrometry (PTR-MS). Odor measurements were performed at four different pig production facilities with and without odor abatement technologies using a newly developed mobile odor laboratory equipped with a PTR-MS for measuring odorants and an olfactometer for measuring the odor concentration by human panelists. A total of 115 odor measurements were carried out in the mobile laboratory and simultaneously air samples were collected in Nalophan bags and analyzed at accredited laboratories after 24 h. The dataset was divided into a calibration dataset containing 94 samples and a validation dataset containing 21 samples. The prediction model based on the measurements in the mobile laboratory was able to explain 74% of the variation in the odor concentration based on odorants, whereas the prediction models based on odor measurements with bag samples explained only 46-57%. This study is the first application of direct field olfactometry to livestock odor and emphasizes the importance of avoiding any bias from sample storage in studies of odor-odorant relationships. Application of the model on the validation dataset gave a high correlation between predicted and measured odor concentration (R2 = 0.77). Significant odorants in the prediction models include phenols and indoles. In conclusion, measurements of odorants on-site in pig production facilities is an alternative to dynamic olfactometry that can be applied for measuring odor from pig houses and the effects of odor abatement technologies.

  19. Cognitive Facilitation Following Intentional Odor Exposure

    PubMed Central

    Johnson, Andrew J.

    2011-01-01

    This paper reviews evidence that, in addition to incidental olfactory pollutants, intentional odor delivery can impact cognitive operations both positively and negatively. Evidence for cognitive facilitation/interference is reviewed alongside four potential explanations for odor-induced effects. It is concluded that the pharmacological properties of odors can induce changes in cognition. However, these effects can be accentuated/attenuated by the shift in mood following odor exposure, expectancy of cognitive effects, and cues to behavior via the contextual association with the odor. It is proposed that greater consideration is required in the intentional utilization of odors within both industrial and private locations, since differential effects are observed for odors with positive hedonic qualities. PMID:22163909

  20. Hydrogen photoproduction in green algae Chlamydomonas reinhardtii sustainable over 2 weeks with the original cell culture without supply of fresh cells nor exchange of the whole culture medium.

    PubMed

    Yagi, Takafumi; Yamashita, Kyohei; Okada, Norihide; Isono, Takumi; Momose, Daisuke; Mineki, Shigeru; Tokunaga, Eiji

    2016-07-01

    Unicellular green algae Chlamydomonas reinhardtii are known to make hydrogen photoproduction under the anaerobic condition with water molecules as the hydrogen source. Since the hydrogen photoproduction occurs for a cell to circumvent crisis of its survival, it is only temporary. It is a challenge to realize persistent hydrogen production because the cells must withstand stressful conditions to survive with alternation of generations in the cell culture. In this paper, we have found a simple and cost-effective method to sustain the hydrogen production over 14 days in the original culture, without supply of fresh cells nor exchange of the culture medium. This is achieved for the cells under hydrogen production in a sulfur-deprived culture solution on the {anaerobic, intense light} condition in a desiccator, by periodically providing a short period of the recovery time (2 h) with a small amount of TAP(+S) supplied outside of the desiccator. As this operation is repeated, the response time of transition into hydrogen production (preparation time) is shortened and the rate of hydrogen production (build up time) is increased. The optimum states of these properties favorable to the hydrogen production are attained in a few days and stably sustained for more than 10 days. Since generations are alternated during this consecutive hydrogen production experiment, it is suggested that the improved hydrogen production properties are inherited to next generations without genetic mutation. The properties are reset only when the cells are placed on the {sulfur-sufficient, aerobic, moderate light} conditions for a long time (more than 1 day at least). PMID:27083446

  1. Characterization of epoxydecenal isomers as potent odorants in black tea (Dimbula) infusion.

    PubMed

    Kumazawa, Kenji; Wada, Yoshiyuki; Masuda, Hideki

    2006-06-28

    In a black tea (Dimbula) infusion, the potent "sweet and/or juicy" odorants were identified as the cis- and trans-4,5-epoxy-(E)-2-decenals by comparison of their gas chromatography retention indices, mass spectra, and odor quality to those of the actual synthetic compounds. Of the two odorants, cis-4,5-epoxy-(E)-2-decenal has been identified for the first time in the black tea. On the basis of the aroma extract dilution analysis on the flavor distillate obtained using the solvent-assisted flavor evaporation technique from the black tea infusion, these isomers showed higher flavor dilution (FD) factors. The FD factors and concentrations of these odorants in the black tea infusion were observed to be much higher than those from Japanese green tea. In addition, the model studies showed that these odorants were generated from linoleic acid and its hydroperoxides by heating, but the generated amounts of these odorants from linoleic acid were much less than those of its hydroperoxides. It can be assumed from these results that the withering and fermentation, which are characteristic processes during the manufacturing of the black tea, which includes the enzymatic reaction such as lipoxygenase, is one of the most important factors for the formation of the epoxydecenal isomers. PMID:16787030

  2. Red junglefowl have individual body odors.

    PubMed

    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. PMID:20435811

  3. Do ambient urban odors evoke basic emotions?

    PubMed Central

    Glass, Sandra T.; Lingg, Elisabeth; Heuberger, Eva

    2013-01-01

    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 (SCR) 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 SCR 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. PMID:24860522

  4. Elaborated Odor Test for Extended Exposure

    NASA Technical Reports Server (NTRS)

    Buchanan, Vanessa D.; Henry, Emily J.; Mast, Dion J.; Harper, Susana A.; Beeson, Harold D.; Tapia, Alma S.

    2016-01-01

    Concerns were raised when incidental exposure to a proprietary bonding material revealed the material had an irritating odor. The NASA-STD-6001B document describes a supplemental test method option for programs to evaluate materials with odor concerns (Test 6, Odor Assessment). In addition to the supplemental standard odor assessment with less than 10 seconds of exposure, the NASA White Sands Test Facility (WSTF) Materials Flight Acceptance Testing section was requested to perform an odor test with an extended duration to evaluate effects of an extended exposure and to more closely simulate realistic exposure scenarios. With approval from the NASA Johnson Space Center Industrial Hygienist, WSTF developed a 15-minute odor test method. WSTF performed this extended-duration odor test to evaluate the odor and physical effects of the bonding material configured between two aluminum plates, after the safety of the gas was verified via toxicity analysis per NASA-STD-6001B Test 7, Determination of Offgassed Products. During extended-duration testing, odor panel members were arranged near the test material in a small room with the air handlers and doors closed to minimize dilution. The odor panel members wafted gas toward themselves and recorded their individual assessments of odor and physical effects at various intervals during the 15-minute exposure and posttest. A posttest interview was conducted to obtain further information. Testing was effective in providing data for comparison and selection of an optimal offgassing and odor containment configuration. The developed test method for extended exposure is proposed as a useful tool for further evaluating materials with identified odors of concern if continued use of the material is anticipated.

  5. Positive relationship between odor identification and affective responses of negatively valenced odors.

    PubMed

    Martinec Nováková, Lenka; Plotěná, Dagmar; Roberts, S Craig; Havlíček, Jan

    2015-01-01

    Hedonic ratings of odors and olfactory preferences are influenced by a number of modulating factors, such as prior experience and knowledge about an odor's identity. The present study addresses the relationship between knowledge about an odor's identity due to prior experience, assessed by means of a test of cued odor identification, and odor pleasantness ratings in children who exhibit ongoing olfactory learning. Ninety-one children aged 8-11 years rated the pleasantness of odors in the Sniffin' Sticks test and, subsequently, took the odor identification test. A positive association between odor identification and pleasantness was found for two unpleasant food odors (garlic and fish): higher pleasantness ratings were exhibited by those participants who correctly identified these odors compared to those who failed to correctly identify them. However, we did not find a similar effect for any of the more pleasant odors. The results of this study suggest that pleasantness ratings of some odors may be modulated by the knowledge of their identity due to prior experience and that this relationship might be more evident in unpleasant odors. PMID:26029143

  6. Characteristic odor components of essential oils from Eurya japonica.

    PubMed

    Motooka, Ryota; Usami, Atsushi; Nakahashi, Hiroshi; Koutari, Satoshi; Nakaya, Satoshi; Shimizu, Ryoyu; Tsuji, Kaoru; Marumoto, Shinsuke; Miyazawa, Mitsuo

    2015-01-01

    The chemical compositions of essential oils from the flower and aerial parts (i.e., leaf and branch) of Eurya japonica were determined and quantified using gas chromatography-mass spectrometry (GC-MS). A total of 87 and 50 compounds were detected in the oils from the flower and aerial parts, respectively. The main compounds of the flower oil were linalool (14.0%), (9Z)-tricosene (12.0%), and nonanal (7.4%). In the oil from the aerial parts, linalool (37.7%), α-terpineol (13.5%), and geraniol (9.6%) were detected. In the oils from the flower and aerial parts, 13 and 8 aroma-active compounds were identified by GC-olfactometry (GC-O) analysis, respectively. The key aroma-active compounds of the flower oil were heptanal [fatty, green, flavor dilution (FD) = 128, odor activity value (OAV) = 346], nonanal (sweet, citrus, FD = 128, OAV = 491), and eugenol (sweet, spicy, FD = 64, OAV = 62): in the oil from the aerial parts, the key aroma-active compounds were linalool (sweet, citrus, FD = 64, OAV = 95), (E)-β-damascenone (sweet, FD = 256, OAV = 4000), and (E)-β-ionone (floral, violet, FD = 128, OAV = 120). This study revealed that nonanal and eugenol impart the sweet, citrus, and spicy odor of the flower oil, while (E)-β-damascenone and (E)-β-ionone contribute the floral and sweet odor of the oil from the aerial parts. PMID:25843279

  7. An in vitro study of manure composition on the biochemical origins, composition, and accumulation of odorous compounds in cattle feedlots.

    PubMed

    Miller, D N; Varel, V H

    2002-09-01

    Very little is known about the biochemical origin of cattle feedlot odors and the environmental factors controlling their production. The tie between diet and manure composition is well established, but the effect of different manure compositions on odorous chemical production is unknown. This study describes the effect of starch, casein, and cellulose substrate additions to slurries of fresh (< 24 h) and aged cattle manure (> 1 d) on the anaerobic production of fermentation products and the consumption of substrates relative to no addition treatments. Aged cattle manure accumulated more VFA (245 to 290 mM) than the fresh manure (91 to 181 mM) irrespective of substrate additions (P < 0.001). In fresh manures, VFA concentrations were increased (P < 0.01) over no addition treatments when carbohydrate (starch or cellulose) was added, whereas starch and protein treatments to aged manure increased VFA content relative to no addition treatments (P < 0.001). Branched-chain VFA and aromatic compounds accumulated only in the aged manure (no addition and protein treatments), indicating that some protein fermentation occurred in those treatments. Based upon substrate loss, starch fermentation was the dominant process in both manures and all treatments with losses exceeding 18.6 g/L. Protein fermentation occurred only in the aged manure, specifically the no addition and protein treatments, when starch was no longer available. The production of odorous compounds from manure was controlled by substrate availability and pH, with pH related to lactate accumulation. We believe that calcareous soil and lactate-consuming microorganisms in the aged manure slurries minimized slurry acidification and resulted in greater accumulations of odorous products. Substrate additions had little effect on the overall accumulation of odor compounds in manure but had profound effects on odor compound composition. We propose that modifying cattle diets to limit starch and protein excretion would

  8. Odor Landscapes in Turbulent Environments

    NASA Astrophysics Data System (ADS)

    Celani, Antonio; Villermaux, Emmanuel; Vergassola, Massimo

    2014-10-01

    The olfactory system of male moths is exquisitely sensitive to pheromones emitted by females and transported in the environment by atmospheric turbulence. Moths respond to minute amounts of pheromones, and their behavior is sensitive to the fine-scale structure of turbulent plumes where pheromone concentration is detectible. The signal of pheromone whiffs is qualitatively known to be intermittent, yet quantitative characterization of its statistical properties is lacking. This challenging fluid dynamics problem is also relevant for entomology, neurobiology, and the technological design of olfactory stimulators aimed at reproducing physiological odor signals in well-controlled laboratory conditions. Here, we develop a Lagrangian approach to the transport of pheromones by turbulent flows and exploit it to predict the statistics of odor detection during olfactory searches. The theory yields explicit probability distributions for the intensity and the duration of pheromone detections, as well as their spacing in time. Predictions are favorably tested by using numerical simulations, laboratory experiments, and field data for the atmospheric surface layer. The resulting signal of odor detections lends itself to implementation with state-of-the-art technologies and quantifies the amount and the type of information that male moths can exploit during olfactory searches.

  9. Odor Sampling: Techniques and Strategies for the Estimation of Odor Emission Rates from Different Source Types

    PubMed Central

    Capelli, Laura; Sironi, Selena; Rosso, Renato Del

    2013-01-01

    Sampling is one of the main issues pertaining to odor characterization and measurement. The aim of sampling is to obtain representative information on the typical characteristics of an odor source by means of the collection of a suitable volume fraction of the effluent. The most important information about an emission source for odor impact assessment is the so-called Odor Emission Rate (OER), which represents the quantity of odor emitted per unit of time, and is expressed in odor units per second (ou·s−1). This paper reviews the different odor sampling strategies adopted depending on source type. The review includes an overview of odor sampling regulations and a detailed discussion of the equipment to be used as well as the mathematical considerations to be applied to obtain the OER in relation to the sampled source typology. PMID:23322098

  10. Odors Discrimination by Olfactory Epithelium Biosensor

    NASA Astrophysics Data System (ADS)

    Liu, Qingjun; Hu, Ning; Ye, Weiwei; Zhang, Fenni; Wang, Hua; Wang, Ping

    2011-09-01

    Humans are exploring the bionic biological olfaction to sense the various trace components of gas or liquid in many fields. For achieving the goal, we endeavor to establish a bioelectronic nose system for odor detection by combining intact bioactive function units with sensors. The bioelectronic nose is based on the olfactory epithelium of rat and microelectrode array (MEA). The olfactory epithelium biosensor generates extracellular potentials in presence of odor, and presents obvious specificity under different odors condition. The odor response signals can be distinguished with each other effectively by signal sorting. On basis of bioactive MEA hybrid system and the improved signal processing analysis, the bioelectronic nose will realize odor discrimination by the specific feature of signals response to various odors.

  11. Receptor arrays optimized for natural odor statistics.

    PubMed

    Zwicker, David; Murugan, Arvind; Brenner, Michael P

    2016-05-17

    Natural odors typically consist of many molecules at different concentrations. It is unclear how the numerous odorant molecules and their possible mixtures are discriminated by relatively few olfactory receptors. Using an information theoretic model, we show that a receptor array is optimal for this task if it achieves two possibly conflicting goals: (i) Each receptor should respond to half of all odors and (ii) the response of different receptors should be uncorrelated when averaged over odors presented with natural statistics. We use these design principles to predict statistics of the affinities between receptors and odorant molecules for a broad class of odor statistics. We also show that optimal receptor arrays can be tuned to either resolve concentrations well or distinguish mixtures reliably. Finally, we use our results to predict properties of experimentally measured receptor arrays. Our work can thus be used to better understand natural olfaction, and it also suggests ways to improve artificial sensor arrays. PMID:27102871

  12. Verbal memory elicited by ambient odor.

    PubMed

    Smith, D G; Standing, L; de Man, A

    1992-04-01

    This study examined whether an ambient odor can act as a contextual cue for retrieval of verbal stimuli. Subjects (N = 47) learned a list of 24 words while exposed to one of two odors (either jasmine incense or Lauren perfume) and subsequently relearned the list with either the same or the alternative odor present. Superior memory for the word list was found when the odor present during the relearning session was the same one that had been present at the time of initial learning, thereby demonstrating context-dependent memory. There were no differences in initial learning between the two odor conditions. No differences in pleasantness or intensity were found between the odors. PMID:1594391

  13. Kraft Board Odor Evaluation by Gas Chromatography and Odor Judging Panel.

    ERIC Educational Resources Information Center

    Fontenot, J. L.

    This is an experimental study which was undertaken to determine if a gas chromatographic technique could be used to measure paperboard odor levels. Because there are many variations to odor testing using a panel of judges - which is the generally accepted method - the author states that, obviously, an objective method for ascertaining odor levels…

  14. Children's Facial Responsiveness to Odors: Influences of Hedonic Valence of Odor, Gender, Age, and Social Presence.

    ERIC Educational Resources Information Center

    Soussignan, Robert; Schall, Benoist

    1996-01-01

    Facial responsiveness to pleasant and unpleasant odors was examined in 5- to 12-year-old children. Children failed to display reflex-like patterns, but exhibited facial configurations that varied according to odor and social condition. Results suggest that facial responsiveness to odors is flexible and able to reorganize and supports emotional and…

  15. Odor preferences shape discrimination learning in rats

    PubMed Central

    Lee, Joshua; Linster, Christiane; Devore, Sasha

    2014-01-01

    Forced-choice discrimination is a standard behavioral paradigm used to test animals’ abilities in learning and memory. In this type of task, a reward association is made between a sensory stimulus and a food or water reward and the frequency of correct choice for the stimulus associated with the reward is measured. We here show that when olfactory sensory stimuli are used, spontaneous preferences for odors can influence speed of acquisition in a forced-choice discrimination task. We first show that among a battery of 53 odorants, some odorants elicit longer bouts of spontaneous investigation than others. We confirm that these odor preferences are robust and reliable by measuring relative spontaneous investigation times for pairs of simultaneously presented odorants. Finally, we show that performance on a forced-choice olfactory discrimination depends on relative spontaneous preferences between the rewarded and unrewarded odorants. Namely, rats acquire novel forced-choice odor discrimination problems significantly faster if the preferred odorant, as assessed by relative spontaneous investigation time, is associated with the reward. These results indicate that even subtle differences in the tendency for an animal to approach and investigate one odorant over another can lead to substantial biases in basic learning and memory tasks. PMID:23895061

  16. Cross-Cultural Color-Odor Associations

    PubMed Central

    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

  17. Enhancement of retronasal odors by taste.

    PubMed

    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. PMID:21798851

  18. Unpleasant odors increase aversion to monetary losses.

    PubMed

    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. PMID:25711689

  19. Cross-cultural color-odor associations.

    PubMed

    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

  20. Enhancement of Retronasal Odors by Taste

    PubMed Central

    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. PMID:21798851

  1. Human olfactory receptor responses to odorants

    PubMed Central

    Mainland, Joel D; Li, Yun R; Zhou, Ting; Liu, Wen Ling L; Matsunami, Hiroaki

    2015-01-01

    Although the human olfactory system is capable of discriminating a vast number of odors, we do not currently understand what chemical features are encoded by olfactory receptors. In large part this is due to a paucity of data in a search space covering the interactions of hundreds of receptors with billions of odorous molecules. Of the approximately 400 intact human odorant receptors, only 10% have a published ligand. Here we used a heterologous luciferase assay to screen 73 odorants against a clone library of 511 human olfactory receptors. This dataset will allow other researchers to interrogate the combinatorial nature of olfactory coding. PMID:25977809

  2. Rats assess degree of relatedness from human odors.

    PubMed

    Ables, Erin M; Kay, Leslie M; Mateo, Jill M

    2007-04-23

    Despite widespread interest in the evolutionary implications of human olfactory communication, the mechanisms underlying human odor production are still poorly understood. Previous studies have demonstrated that human odor cues are related to variations in the major histocompatibility complex, but it is unclear whether odors are associated with overall genotypic variation. In this study, we investigated whether more closely related humans produce more similar odor cues. To assess objective odor qualities we tested odor similarity using rats in a habituation-discrimination paradigm. Rats were first habituated to a referent human odor and were then presented with two test odors obtained from individuals related in different degrees to the referent. Investigation times for each odor were compared. Because rats investigate novel odors longer than familiar odors, we were able to determine which test odor the rats perceived as more similar to the referent human odor. For six of ten odor donor families, rats investigated the odor of the less closely related individual significantly longer than that of the more closely related individual, and investigation durations were in the expected direction for all families. These results indicate that similarity of human odor cues is associated with degree of genetic relatedness, with more closely related humans producing more similar odor cues. This study supports the hypothesis that odor cues provide information regarding degree of relatedness and may thus affect a wide variety of human behaviors, including kin preferences, nepotism, and mate choice. PMID:17261318

  3. Classification of tea category using a portable electronic nose based on an odor imaging sensor array.

    PubMed

    Chen, Quansheng; Liu, Aiping; Zhao, Jiewen; Ouyang, Qin

    2013-10-01

    A developed portable electronic nose (E-nose) based on an odor imaging sensor array was successfully used for classification of three different fermentation degrees of tea (i.e., green tea, black tea, and Oolong tea). The odor imaging sensor array was fabricated by printing nine dyes, including porphyrin and metalloporphyrins, on the hydrophobic porous membrane. A color change profile for each sample was obtained by differentiating the image of sensor array before and after exposure to tea's volatile organic compounds (VOCs). Multivariate analysis was used for the classification of tea categories, and linear discriminant analysis (LDA) achieved 100% classification rate by leave-one-out cross-validation (LOOCV). This study demonstrates that the E-nose based on odor imaging sensor array has a high potential in the classification of tea category according to different fermentation degrees. PMID:23810847

  4. Deodorant Characteristics of Breath Odor Occurred from Favorite Foods Using Metal Oxide Gas Sensors

    NASA Astrophysics Data System (ADS)

    Seto, Shuichi; Oyabu, Takashi; Cai, Kuiqian; Katsube, Teruaki

    Three types of metal oxide gas sensors were adopted to detect the degree of breath odor. Various sorts of information are included in the odor. Each sensor has different sensitivities to gaseous chemical substances and the sensitivities also differ according to human behaviors, for example taking a meal, teeth-brushing and drinking something. There is also a possibility that the sensor can detect degrees of daily fatigue. Sensor sensitivities were low for the expiration of the elderly when the subject drank green tea. In this study, it is thought that the odor system can be incorporated into a healing robot. The robot can communicate with the elderly using several words and also connect to Internet. As for the results, the robot can identify basic human behaviors and recognize the living conditions of the resident. Moreover, it can also execute a kind of information retrieval through the Internet. Therefore, it has healing capability for the aged, and can also receive and transmit information.

  5. Odor Experience Facilitates Sparse Representations of New Odors in a Large-Scale Olfactory Bulb Model

    PubMed Central

    Zhou, Shanglin; Migliore, Michele; Yu, Yuguo

    2016-01-01

    Prior odor experience has a profound effect on the coding of new odor inputs by animals. The olfactory bulb, the first relay of the olfactory pathway, can substantially shape the representations of odor inputs. How prior odor experience affects the representation of new odor inputs in olfactory bulb and its underlying network mechanism are still unclear. Here we carried out a series of simulations based on a large-scale realistic mitral-granule network model and found that prior odor experience not only accelerated formation of the network, but it also significantly strengthened sparse responses in the mitral cell network while decreasing sparse responses in the granule cell network. This modulation of sparse representations may be due to the increase of inhibitory synaptic weights. Correlations among mitral cells within the network and correlations between mitral network responses to different odors decreased gradually when the number of prior training odors was increased, resulting in a greater decorrelation of the bulb representations of input odors. Based on these findings, we conclude that the degree of prior odor experience facilitates degrees of sparse representations of new odors by the mitral cell network through experience-enhanced inhibition mechanism. PMID:26903819

  6. Positive relationship between odor identification and affective responses of negatively valenced odors

    PubMed Central

    Martinec Nováková, Lenka; Plotěná, Dagmar; Roberts, S. Craig; Havlíček, Jan

    2015-01-01

    Hedonic ratings of odors and olfactory preferences are influenced by a number of modulating factors, such as prior experience and knowledge about an odor’s identity. The present study addresses the relationship between knowledge about an odor’s identity due to prior experience, assessed by means of a test of cued odor identification, and odor pleasantness ratings in children who exhibit ongoing olfactory learning. Ninety-one children aged 8–11 years rated the pleasantness of odors in the Sniffin’ Sticks test and, subsequently, took the odor identification test. A positive association between odor identification and pleasantness was found for two unpleasant food odors (garlic and fish): higher pleasantness ratings were exhibited by those participants who correctly identified these odors compared to those who failed to correctly identify them. However, we did not find a similar effect for any of the more pleasant odors. The results of this study suggest that pleasantness ratings of some odors may be modulated by the knowledge of their identity due to prior experience and that this relationship might be more evident in unpleasant odors. PMID:26029143

  7. Perceptual blending in odor mixtures depends on the nature of odorants and human olfactory expertise.

    PubMed

    Barkat, S; Le Berre, E; Coureaud, G; Sicard, G; Thomas-Danguin, T

    2012-02-01

    Our olfactory system is confronted with complex mixtures of odorants, often recognized as single entities due to odor blending (e.g., coffee). In contrast, we are also able to discriminate odors from complex mixtures (e.g., off-odors). Therefore, the olfactory system is able to engage either configural or elemental processes when confronted with mixtures. However, the rules that govern the involvement of these processes during odor perception remain poorly understood. In our first experiment, we examined whether simple odorant mixtures (binary/ternary) could elicit configural perception. Twenty untrained subjects were asked to evaluate the odor typicality of mixtures and their constituents. The results revealed a significant increase in odor typicality in some but not all mixtures as compared with the single components, which suggest that perceptual odor blending can occur only in specific mixtures (configural processing). In our second experiment, we tested the hypothesis that general olfactory expertise can improve elemental perception of mixtures. Thirty-two trained subjects evaluated the odor typicality of the stimuli presented during the first experiment, and their responses were compared with those obtained from the untrained panelists. The results support the idea that general training with odors increases the elemental perception of binary and ternary blending mixtures. PMID:21873604

  8. Odor Experience Facilitates Sparse Representations of New Odors in a Large-Scale Olfactory Bulb Model.

    PubMed

    Zhou, Shanglin; Migliore, Michele; Yu, Yuguo

    2016-01-01

    Prior odor experience has a profound effect on the coding of new odor inputs by animals. The olfactory bulb, the first relay of the olfactory pathway, can substantially shape the representations of odor inputs. How prior odor experience affects the representation of new odor inputs in olfactory bulb and its underlying network mechanism are still unclear. Here we carried out a series of simulations based on a large-scale realistic mitral-granule network model and found that prior odor experience not only accelerated formation of the network, but it also significantly strengthened sparse responses in the mitral cell network while decreasing sparse responses in the granule cell network. This modulation of sparse representations may be due to the increase of inhibitory synaptic weights. Correlations among mitral cells within the network and correlations between mitral network responses to different odors decreased gradually when the number of prior training odors was increased, resulting in a greater decorrelation of the bulb representations of input odors. Based on these findings, we conclude that the degree of prior odor experience facilitates degrees of sparse representations of new odors by the mitral cell network through experience-enhanced inhibition mechanism. PMID:26903819

  9. Sparse, Decorrelated Odor Coding in the Mushroom Body Enhances Learned Odor Discrimination

    PubMed Central

    Lin, Andrew C.; Bygrave, Alexei; de Calignon, Alix; Lee, Tzumin; Miesenböck, Gero

    2014-01-01

    Summary Sparse coding may be a general strategy of neural systems to augment memory capacity. In Drosophila, sparse odor coding by the Kenyon cells of the mushroom body is thought to generate a large number of precisely addressable locations for the storage of odor-specific memories. However, it remains untested how sparse coding relates to behavioral performance. Here we demonstrate that sparseness is controlled by a negative feedback circuit between Kenyon cells and the GABAergic anterior paired lateral (APL) neuron. Systematic activation and blockade of each leg of this feedback circuit show that Kenyon cells activate APL and APL inhibits Kenyon cells. Disrupting the Kenyon cell-APL feedback loop decreases the sparseness of Kenyon cell odor responses, increases inter-odor correlations, and prevents flies from learning to discriminate similar, but not dissimilar, odors. These results suggest that feedback inhibition suppresses Kenyon cell activity to maintain sparse, decorrelated odor coding and thus the odor-specificity of memories. PMID:24561998

  10. [Selective feeding in fish: Effect of feeding and defensive motivations evoked by natural odors].

    PubMed

    Kasumyan, A O; Marusov, E A

    2015-01-01

    The effect of feeding and defensive motivations evoked by natural olfactory signals (the food odor, the alarm pheromone) on choice and consumption of food items different in color and taste, and the manifestation of foraging behavior were examined in fish (koi Cyprinus carpio, roach Rutilus rutilus). The agar-agar pellets of red and green color having one of the amino acids (glycine, L-proline, L-alanine; all in concentration of 0.1 M) were simultaneously offered to single fishes in pure water, and in water extract of Chironomidae larvae or in water extract of fish skin. It was found out that odors used have different effects on fish foraging activity and on pellet selection for both pellet choice and consumption. On background of food odor, fish grasped pellets more often than in pure water. The equal choice of red and green pellets in pure water shifted to the preference of red ones in the presence of food odor. Despite the increase in the absolute number of pellets grasped, the relative consumption reduced and was replaced by selective consumption of pellets with glycine regardless of their color. Increasing demand for the food quality, due to the increased feeding motivation in response to food odor, is an important adaptation enhancing selection and consumption of food with more appropriate sensory qualities for fish. Defensive motivation caused by alarm pheromone suppressed predisposition. of fish to feed. Fish grasped pellets several times less often than in pure water and refused most of them. Any changes in the color or taste preferences were absent. Feeding behavior of fish of both species was characterized by repeated intraoral pellet testing, but in koi handling was less typical than in roach. In both species, handling activity was higher in those cases when the pellet was finally rejected. This activity was enhanced also on the background of food odor. PMID:26201217

  11. Water Treatment Technology - Taste, Odor & Color.

    ERIC Educational Resources Information Center

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on taste, odor, and color provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: taste and odor determination, control of…

  12. Design considerations: Upgrading Boston Gas odorant stations

    SciTech Connect

    Flynn, E.

    1995-05-01

    Boston Gas Company (BGC) has progressed beyond the half-way point on a four-year program to upgrade its odorant injection systems. An experienced odorization team from BGC`s Gas Supply and Production Department set out to redesign odorant storage, piping and injection system operation and to research the availability of improved odorization equipment. Research included investigating odorization practices of other gas companies and new technologies offered by odorization equipment manufacturers. The NJEX system and other innovations used in BGC`s odorization operation have proven effective since their inception. The system has provided reliable metering, consistent injection rates and accurate data storage. The controller has greatly simplified programming, troubleshooting and system monitoring. Innovations such as back welded fittings, Viton O-ring seal fittings, diaphragm valves, and complete combustion flares have provided reliable odor-free operation, filling and maintenance. The system`s simple mechanical layout, the user`s manual, and closed loop purging and priming have lowered the learning curve for operating personnel, and reduce man hours for maintenance and troubleshooting.

  13. 46 CFR 58.16-25 - Odorization.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Odorization. 58.16-25 Section 58.16-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Liquefied Petroleum Gases for Cooking and Heating § 58.16-25 Odorization. (a)...

  14. 46 CFR 58.16-25 - Odorization.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Odorization. 58.16-25 Section 58.16-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Liquefied Petroleum Gases for Cooking and Heating § 58.16-25 Odorization. (a)...

  15. 46 CFR 58.16-25 - Odorization.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Odorization. 58.16-25 Section 58.16-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Liquefied Petroleum Gases for Cooking and Heating § 58.16-25 Odorization. (a)...

  16. 46 CFR 58.16-25 - Odorization.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Odorization. 58.16-25 Section 58.16-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Liquefied Petroleum Gases for Cooking and Heating § 58.16-25 Odorization. (a)...

  17. 46 CFR 58.16-25 - Odorization.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Odorization. 58.16-25 Section 58.16-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Liquefied Petroleum Gases for Cooking and Heating § 58.16-25 Odorization. (a)...

  18. Age-Related Changes in Odor Discrimination

    ERIC Educational Resources Information Center

    Stevenson, Richard J.; Mahmut, Mehmet; Sundqvist, Nina

    2007-01-01

    Odor naming and recognition memory are poorer in children than in adults. This study explored whether such differences might result from poorer discriminative ability. Experiment 1 used an oddity test of discrimination with familiar odors on 6-year-olds, 11-year-olds, and adults. Six-year-olds were significantly poorer at discrimination relative…

  19. Predicting Odor Pleasantness with an Electronic Nose

    PubMed Central

    Haddad, Rafi; Medhanie, Abebe; Roth, Yehudah; Harel, David; Sobel, Noam

    2010-01-01

    A primary goal for artificial nose (eNose) technology is to report perceptual qualities of novel odors. Currently, however, eNoses primarily detect and discriminate between odorants they previously “learned”. We tuned an eNose to human odor pleasantness estimates. We then used the eNose to predict the pleasantness of novel odorants, and tested these predictions in naïve subjects who had not participated in the tuning procedure. We found that our apparatus generated odorant pleasantness ratings with above 80% similarity to average human ratings, and with above 90% accuracy at discriminating between categorically pleasant or unpleasant odorants. Similar results were obtained in two cultures, native Israeli and native Ethiopian, without retuning of the apparatus. These findings suggest that unlike in vision and audition, in olfaction there is a systematic predictable link between stimulus structure and stimulus pleasantness. This goes in contrast to the popular notion that odorant pleasantness is completely subjective, and may provide a new method for odor screening and environmental monitoring, as well as a critical building block for digital transmission of smell. PMID:20418961

  20. 46 CFR 169.571 - Odorizing units.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Odorizing units. 169.571 Section 169.571 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Lifesaving and Firefighting Equipment Firefighting Equipment § 169.571 Odorizing units. Each carbon...

  1. 46 CFR 169.571 - Odorizing units.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Odorizing units. 169.571 Section 169.571 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Lifesaving and Firefighting Equipment Firefighting Equipment § 169.571 Odorizing units. Each carbon...

  2. 46 CFR 169.571 - Odorizing units.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Odorizing units. 169.571 Section 169.571 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Lifesaving and Firefighting Equipment Firefighting Equipment § 169.571 Odorizing units. Each carbon...

  3. From the Cover: Odor maps in the olfactory cortex

    NASA Astrophysics Data System (ADS)

    Zou, Zhihua; Li, Fusheng; Buck, Linda B.

    2005-05-01

    In the olfactory system, environmental chemicals are deconstructed into neural signals and then reconstructed to form odor perceptions. Much has been learned about odor coding in the olfactory epithelium and bulb, but little is known about how odors are subsequently encoded in the cortex to yield diverse perceptions. Here, we report that the representation of odors by fixed glomeruli in the olfactory bulb is transformed in the cortex into highly distributed and multiplexed odor maps. In the mouse olfactory cortex, individual odorants are represented by subsets of sparsely distributed neurons. Different odorants elicit distinct, but partially overlapping, patterns that are strikingly similar among individuals. With increases in odorant concentration, the representations expand spatially and include additional cortical neurons. Structurally related odorants have highly related representations, suggesting an underlying logic to the mapping of odor identities in the cortex. odorant receptor | smell

  4. Functional identification of a goldfish odorant receptor.

    PubMed

    Speca, D J; Lin, D M; Sorensen, P W; Isacoff, E Y; Ngai, J; Dittman, A H

    1999-07-01

    The vertebrate olfactory system utilizes odorant receptors to receive and discriminate thousands of different chemical stimuli. An understanding of how these receptors encode information about an odorant's molecular structure requires a characterization of their ligand specificities. We employed an expression cloning strategy to identify a goldfish odorant receptor that is activated by amino acids-potent odorants for fish. Structure-activity analysis indicates that the receptor is preferentially tuned to recognize basic amino acids. The receptor is a member of a multigene family of G protein-coupled receptors, sharing sequence similarities with the calcium sensing, metabotropic glutamate, and V2R class of vomeronasal receptors. The ligand tuning properties of the goldfish amino acid odorant receptor provide information for unraveling the molecular mechanisms underlying olfactory coding. PMID:10433261

  5. The extremely broad odorant response profile of mouse olfactory sensory neurons expressing the odorant receptor MOR256-17 includes trace amine-associated receptor ligands.

    PubMed

    Tazir, Bassim; Khan, Mona; Mombaerts, Peter; Grosmaitre, Xavier

    2016-03-01

    The mouse olfactory system employs ~1100 G-protein-coupled odorant receptors (ORs). Each mature olfactory sensory neuron (OSN) is thought to express just one OR gene, and the expressed OR determines the odorant response properties of the OSN. The broadest odorant response profile thus far demonstrated in native mouse OSNs is for OSNs that express the OR gene SR1 (also known as Olfr124 and MOR256-3). Here we showed that the odorant responsiveness of native mouse OSNs expressing the OR gene MOR256-17 (also known as Olfr15 and OR3) is even broader than that of OSNs expressing SR1. We investigated the electrophysiological properties of green fluorescent protein (GFP)+ OSNs in a MOR256-17-IRES-tauGFP gene-targeted mouse strain, in parallel with GFP+ OSNs in the SR1-IRES-tauGFP gene-targeted mouse strain that we previously reported. Of 35 single chemical compounds belonging to distinct structural classes, MOR256-17+ OSNs responded to 31 chemicals, compared with 10 for SR1+ OSNs. The 10 compounds that activated SR1+ OSNs also activated MOR256-17+ OSNs. Interestingly, MOR256-17+ OSNs were activated by three amines (cyclohexylamine, isopenthylamine, and phenylethylamine) that are typically viewed as ligands for chemosensory neurons in the main olfactory epithelium that express trace amine-associated receptor genes, a family of 15 genes encoding G-protein-coupled receptors unrelated in sequence to ORs. We did not observe differences in membrane properties, indicating that the differences in odorant response profiles between the two OSN populations were due to the expressed OR. MOR256-17+ OSNs appear to be at one extreme of odorant responsiveness among populations of OSNs expressing distinct OR genes in the mouse. PMID:26666691

  6. A statistical property of fly odor responses is conserved across odors.

    PubMed

    Stevens, Charles F

    2016-06-14

    I have reanalyzed the data presented by Hallem and Carlson [Hallem EA, Carlson JR (2006) Cell 125(1):143-160] and shown that the combinatorial odor code supplied by the fruit fly antenna is a very simple one in which nearly all odors produce, statistically, the same neuronal response; i.e., the probability distribution of sensory neuron firing rates across the population of odorant sensory neurons is an exponential for nearly all odors and odor mixtures, with the mean rate dependent on the odor concentration. Between odors, then, the response differs according to which sensory neurons are firing at what individual rates and with what mean population rate, but not in the probability distribution of firing rates. This conclusion is independent of adjustable parameters, and holds both for monomolecular odors and complex mixtures. Because the circuitry in the antennal lobe constrains the mean firing rate to be the same for all odors and concentrations, the odor code is what is known as maximum entropy. PMID:27247407

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

    PubMed Central

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

    2014-01-01

    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. PMID:25010698

  8. Identifying and tracking key odorants from cattle feedlots

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Odors from cattle feedlots negatively affect air quality in local communities. The purpose of this study was to identifying key odorants using both analytical (odor activity values, OAV) and gas chromatrography GC-O (olfactometry) techniques, compare odor threshold databases, and track the movement ...

  9. 9 CFR 311.20 - Sexual odor of swine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Sexual odor of swine. 311.20 Section... Sexual odor of swine. (a) Carcasses of swine which give off a pronounced sexual odor shall be condemned. (b) The meat of swine carcasses which give off a sexual odor less than pronounced may be passed...

  10. 9 CFR 311.20 - Sexual odor of swine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Sexual odor of swine. 311.20 Section... Sexual odor of swine. (a) Carcasses of swine which give off a pronounced sexual odor shall be condemned. (b) The meat of swine carcasses which give off a sexual odor less than pronounced may be passed...

  11. 9 CFR 311.20 - Sexual odor of swine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Sexual odor of swine. 311.20 Section... Sexual odor of swine. (a) Carcasses of swine which give off a pronounced sexual odor shall be condemned. (b) The meat of swine carcasses which give off a sexual odor less than pronounced may be passed...

  12. 9 CFR 311.20 - Sexual odor of swine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Sexual odor of swine. 311.20 Section... Sexual odor of swine. (a) Carcasses of swine which give off a pronounced sexual odor shall be condemned. (b) The meat of swine carcasses which give off a sexual odor less than pronounced may be passed...

  13. 9 CFR 311.20 - Sexual odor of swine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Sexual odor of swine. 311.20 Section... Sexual odor of swine. (a) Carcasses of swine which give off a pronounced sexual odor shall be condemned. (b) The meat of swine carcasses which give off a sexual odor less than pronounced may be passed...

  14. Volatile organic compounds of six French Dryopteris species: natural odorous and bioactive resources.

    PubMed

    Froissard, Didier; Rapior, Sylvie; Bessière, Jean-Marie; Fruchier, Alain; Buatois, Bruno; Fons, Françoise

    2014-01-01

    Aerial parts of six Dryopteris species collected in France were investigated for volatile organic compounds (VOC) for the first time. Fifty-three biosynthesized VOC from the shikimic, lipidic and terpenic pathways were identified using gas chromatography/mass spectrometry. Many bioactive polyketide compounds as filicinic derivatives (from 8.5 to 23.5%) and phloroglucinol derivatives (from 8.2 to 53.8%) with various pharmacological activities were detected in high amount from five analysed Dryopteris species, in particular D. oreades and D. borreri, i.e., propionylfilicinic acid (> 10% in D. affinis and D. ardechensis) and 2,6-dihydroxy-4-methoxy-3-methylbutyrophenone (aspidinol) (19.1% and 14.6% in D. oreades and D. borreri, respectively). Several terpenic derivatives with a low odor threshold were identified, i.e., carota-5,8-diene (from 2.5 to 18.4%: floral, woody or fresh bark note), (E)-nerolidol (> 10% for D. borreri and D. cambrensis; floral or woody odor), alpha-selinene (> 7% for D. ardechensis; woody-spicy odor), and aristolene (12.8% in D. affinis; flower, sweet odor). The main isoprenoid derivatives were 4-hydroxy-5,6-epoxyionol, 3-oxo-alpha-ionol and 4-oxo-7,8-dihydro-beta-ionone (essentially in D. remota), whereas the main aromatic compound was 4-hydroxy-3-methoxyacetophenone (20.6% and 12.6% in D. cambrensis and D. borreri, respectively) and the main lipid derivative was 1-octen-3-ol with a mushroom-like odor (from 0.4 to 8.3%). Dryopteris species resources are of great interest as a reservoir of odorous and bioactive compounds. PMID:24660483

  15. Bleaching process preferred to decontaminate odorants

    SciTech Connect

    1996-10-01

    The problem of decontaminating and disposing of out-of-service gas odorizers has long faced both gas transmission and distribution companies since the early 1980s. Finding a methodology to safely and effectively decontaminate odorant-contaminated equipment has caused many companies to simply cap the equipment and put it in storage. The recommended process of decontamination by odorant manufacturers is currently a bleaching-type process. A sodium hypochlorite solution is added to water and either circulated or left standing in the contaminated equipment. The sodium hypochlorite effectively neutralizes the smell of the odorant and slightly corrodes the inside of the equipment to neutralize any odorant which has permeated the metal. The waste sodium hypochlorite and water is then shipped as hazardous waste (pH of 12.5) or non-hazardous waste after the pH has been adjusted. The bleaching process has proven cost-effective and less time-consuming than most other methods including bioremediation. To effectively use it, there are several problems to overcome--most importantly the removal of residual product and the release of vapors into the atmosphere. River Valley Technologies, a contractor located in Cincinnati, OH, specializing in odorant-equipment decontamination, has developed several methods and engineering controls to eliminate most of the problems associated with decontaminating odorant equipment. The paper describes these methods.

  16. The implicit association between odors and illness.

    PubMed

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

    2009-02-01

    Some individuals ascribe health symptoms to odor exposures, even when none would be expected based on toxicological dose-effect relationships. In these situations, symptoms are believed to have been mediated by beliefs regarding the potential health effects from odorants, which implies a controlled type of information processing. From an evolutionary perspective, such a form of processing may hardly be the only route. The aim of the present study was to explore the viability of a fast and implicit route, by investigating automatic odor-related associations in the context of health. An Implicit Association Test assessing association strengths between the concept odor and the concepts healthy and sick was conducted. Three experiments (N=66, N=64, and N=64) showed a significantly stronger association between the concepts odor and sick than between odor and healthy. These results did not match explicit associations and provide evidence for a fast and automatic route of processing that may complement consciously controlled processes. A dual-processing theory of olfactory information is proposed leading to new hypotheses regarding the development and maintenance of odor-induced health symptoms. PMID:18936154

  17. Sexual odor discrimination and physiological profiles in adult male rats after a neonatal, short term, reversible nasal obstruction.

    PubMed

    Thornton, S N; Padzys, G S; Trabalon, M

    2014-05-01

    The present study was designed to examine behavioral responses (interpreted as preferences) to olfactory cues (nest bedding odor and odors of estrous and anestrus females) in adult male rats after they had a short term reversible, bilateral, nasal obstruction (RbNO) as developing rat pups. These results were compared to behavior of control (untreated) and sham operated male littermates. Behavioral tests and physiological parameters were analyzed 90 days after recovery of nasal breathing. Experiments investigated the time spent in arms or the center of a maze of male rats in response to odors from the nest bedding or from adult females. There were no differences in responses between untreated, sham and RbNO adult male rats to fresh and nest bedding odors. RbNO males spent more time in the center of the maze when given a choice of estrus or anestrus female odors, or bedding odors from untreated or sham operated female rats. In contrast untreated and sham male rats preferred the odors of estrous females and of untreated or sham females. Plasma corticosterone levels in the males increased during the behavioral tests. Plasma testosterone levels were significantly lower in RbNO males compared to untreated males and did not increase during the behavioral tests compared to sham operated males. Males from all groups had similar preferences for the odor of bedding from adult RbNO females. Plasma levels of cholesterol and triglycerides were increased in RbNO adults. In conclusion, short term nasal obstruction in males while juvenile has long term consequences on hormones and behavioral preferences, thus potential partner selection when adult. PMID:24769524

  18. Pain tolerance selectively increased by a sweet-smelling odor.

    PubMed

    Prescott, John; Wilkie, Jenell

    2007-04-01

    The mechanism underlying reported analgesic effects of odors in humans is unclear, although odor hedonics has been implicated. We tested whether odors that are sweet smelling through prior association with tasted sweetness might influence pain by activating the same analgesic mechanisms as sweet tastes. Inhalation of a sweet-smelling odor during a cold-pressor test increased tolerance for pain compared with inhalation of pleasant and unpleasant low-sweetness odors and no odor. There were no significant differences in pain ratings among the odor conditions. These results suggest that smelled sweetness can produce a naturally occurring conditioned increase in pain tolerance. PMID:17470253

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

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed Central

    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 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. PMID:27053070

  1. Odor mental imagery in non-experts in odors: a paradox?

    PubMed

    Royet, Jean-Pierre; Delon-Martin, Chantal; Plailly, Jane

    2013-01-01

    In agreement with the theoretical framework stipulating that mental images arise from neural activity in early sensory cortices, the primary olfactory cortex [i.e., the piriform cortex (PC)] is activated when non-olfactory-experts try to generate odor mental images. This finding strongly contrasts with the allegation that it is typically impossible to mentally imagine odors. However, other neurophysiological or cognitive processes engaged in the endeavor of odor mental imagery such as sniffing, attention, expectation, and cross-modal interactions involve the PC and could explain this paradox. To unambiguously study the odor mental imagery, we first argued the need to investigate odor experts who have learned to specifically reactivate olfactory percepts. We then assert the necessity to explore the network dedicated to this function by considering variations in both the activity level and the connection strength of the areas belonging to this network as a function of the level of expertise of the odor experts. PMID:23519325

  2. Fabrication of Odor Sensor Using Peptide

    NASA Astrophysics Data System (ADS)

    Hotokebuchi, Yuta; Hayashi, Kenshi; Toko, Kiyoshi; Chen, Ronggang; Ikezaki, Hidekazu

    We report fabrication of an odor sensor using peptides. Peptides were designed to acquire the specific reception for a target odor molecule. Au surface of the sensor electrode was coated by the designed peptide using the method of self assembled monolayers (SAMs). Functionalized Au surfaces by the peptides were confirmed by ellipsometry and cyclic voltammetry. The odorants of vanillin, phenethyl alcohol and hexanol were discriminated by QCM sensor with the peptide surface. Moreover, we verified specific interaction between amino acid (Trp) and vanillin by fluorescence assay.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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. Odor-fading prevention from organosulfur-odorized liquefied petroleum gas

    SciTech Connect

    Nevers, A.D.

    1987-10-20

    A process is described for the prevention of odor-fading from organosulfur-odorized LPG stored in containers having active interior steel surfaces. It consists of treating the surfaces with a deactivating amount of benzotriazole, tolyl triazole, mercaptobenzothiazole, benzothiazyl disulfide, or mixtures thereof, and loading the container with liquefied petroleum gas odorized with at least one reduced organosulfur compounds containing one to five carbon atoms.

  5. Olfaction Presentation System Using Odor Scanner and Odor-Emitting Apparatus Coupled with Chemical Capsules of Alginic Acid Polymer

    NASA Astrophysics Data System (ADS)

    Sakairi, Minoru; Nishimura, Ayako; Suzuki, Daisuke

    For the purpose of the application of odor to information technology, we have developed an odor-emitting apparatus coupled with chemical capsules made of alginic acid polymer. This apparatus consists of a chemical capsule cartridge including chemical capsules of odor ingredients, valves to control odor emission, and a temperature control unit. Different odors can be easily emitted by using the apparatus. We have developed an integrated system of vision, audio and olfactory information in which odor strength can be controlled coinciding with on-screen moving images based on analytical results from the odor scanner.

  6. Time course of androgenic modulation of odor preferences and odor cues in male meadow voles, Microtus pennsylvanicus.

    PubMed

    Ferkin, M H

    1992-12-01

    During the breeding season, male meadow voles prefer female over male odors and females prefer male over female odors. Testosterone control of males' odor preferences and production of odors attractive to females differ. A male meadow vole's preference for female versus male odor was still evident 1 week after castration, but not 1 week later. This preference was reinstated in testosterone-treated male voles 2 weeks after the onset of hormone replacement. The attractiveness of male odors to females did not disappear until 3 weeks after castration. The attractiveness of male odors was reinstated 1 week after castrated males were treated with testosterone. The time course for the androgenic modulation of production of odors attractive to females may facilitate breeding. For example, at the end of the breeding season males may emit an odor that is still attractive to females. Similarly, at the beginning of the breeding season males may emit an odor that is attractive to females. PMID:1478635

  7. Odorant receptors of Drosophila are sensitive to the molecular volume of odorants.

    PubMed

    Saberi, Majid; Seyed-Allaei, Hamed

    2016-01-01

    Which properties of a molecule define its odor? This is a basic yet unanswered question regarding the olfactory system. The olfactory system of Drosophila has a repertoire of approximately 60 odorant receptors. Molecules bind to odorant receptors with different affinities and activate them with different efficacies, thus providing a combinatorial code that identifies odorants. We hypothesized that the binding affinity of an odorant-receptor pair is affected by their relative sizes. The maximum affinity can be attained when the molecular volume of an odorant matches the volume of the binding pocket. The affinity drops to zero when the sizes are too different, thus obscuring the effects of other molecular properties. We developed a mathematical formulation of this hypothesis and verified it using Drosophila data. We also predicted the volume and structural flexibility of the binding site of each odorant receptor; these features significantly differ between odorant receptors. The differences in the volumes and structural flexibilities of different odorant receptor binding sites may explain the difference in the scents of similar molecules with different sizes. PMID:27112241

  8. Odorant receptors of Drosophila are sensitive to the molecular volume of odorants

    PubMed Central

    Saberi, Majid; Seyed-allaei, Hamed

    2016-01-01

    Which properties of a molecule define its odor? This is a basic yet unanswered question regarding the olfactory system. The olfactory system of Drosophila has a repertoire of approximately 60 odorant receptors. Molecules bind to odorant receptors with different affinities and activate them with different efficacies, thus providing a combinatorial code that identifies odorants. We hypothesized that the binding affinity of an odorant-receptor pair is affected by their relative sizes. The maximum affinity can be attained when the molecular volume of an odorant matches the volume of the binding pocket. The affinity drops to zero when the sizes are too different, thus obscuring the effects of other molecular properties. We developed a mathematical formulation of this hypothesis and verified it using Drosophila data. We also predicted the volume and structural flexibility of the binding site of each odorant receptor; these features significantly differ between odorant receptors. The differences in the volumes and structural flexibilities of different odorant receptor binding sites may explain the difference in the scents of similar molecules with different sizes. PMID:27112241

  9. Fresh SETI Strategies

    NASA Astrophysics Data System (ADS)

    Tough, A.

    If a smart probe or some other form of extraterrestrial intelligence has reached our planet, what is the next logical step in our scientific search for it? Fresh new search strategies are required. One innovative strategy, an invitation to ETI launched in 1996, was made possible by the creation of the World Wide Web. Other fresh search strategies, too, are emerging.

  10. Odor aversion learning by the rat fetus.

    PubMed

    Smotherman, W P

    1982-11-01

    Rat fetuses were exposed to an odor stimulus on day 20 of gestation via amniotic injection and then injected with LiCl. In a CER paradigm, 10 day old pups were trained to approach an anesthetized dam in a runway for suckling reinforcement. When running speeds had stabilized the odor stimulus experienced in-utero was introduced into the test chamber. This odor took on aversive properties as a function of its pairing with LiCl, as evidenced by a decrease in running speed on CER trials and increases in the number of trials that were terminated because pups failed to traverse the runway. These data indicate that the fetal rat is capable of odor aversion learning. PMID:6296892

  11. Odor Generation in the Kraft Process

    ERIC Educational Resources Information Center

    Karnofski, Michael A.

    1975-01-01

    Describes the chemical compounds responsible for the odor generated in the Kraft process of pulping wood chips; this subject can be used as a relevant topic in introductory chemistry, especially environmental chemistry. (MLH)

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

    ERIC Educational Resources Information Center

    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…

  13. Composting public health aspects: Odors and bioaerosols

    SciTech Connect

    Williams, T.O.; Epstein, E.

    1995-09-01

    The two dominating public health issues associated with composting are odors and bioaerosols, regardless of the feedstock or method of composting. Odors, per se, are an irritant and a nuisance rather than a direct health problem. However, when odors emanate form a facility, the surrounding public often associates odors with compounds which may result in health problems. For example, hydrogen sulfide is not found in high concentrations during composting or found to be of a health significance in the air surrounding composting facilities, yet health issues related to this compound have emerged as a result of odors. Another health concern associated with odors is bioaerosols. Bioaerosols are biological organisms or substances from biological organisms which have been implicated in human health. Bioaerosols may contain fungal spores, actinomycetes, microbial products, and other organisms. Mitigating odors and bioaerosols is a function of facility design and operations. There is a greater opportunity in municipal solid waste (MSW) and biosolids facilities for effective design than with year waste facilities. MSW and biosolids facilities as a result of the nature of the feedstock generally require more sophisticated materials handling equipment which require enclosures. With enclosures there is a greater opportunity to scrub the air for removal of odors and dust. There are also more regulatory requirements for MSW and sewage sludge composting for both process and product by states and the Federal government. The objective of this paper is to provide information on the concerns, state-of-the-art, and potential mitigating aspects which need to be considered in the design and operation of MSW facilities.

  14. Odors and the perception of hygiene.

    PubMed

    Kerr, Kara-Lynne; Rosero, Stephanie Joyce; Doty, Richard L

    2005-02-01

    Although certain odors, such as lemon, are commonly associated with cleanliness and positive hygiene, empirical assessment of such associations for other odors and attributes is generally lacking. Moreover, differences between men and women in such associations have not been established. In this study of lemon, onion, pine, and smoke odors, ratings were obtained from 142 men and 336 women (M age= 30.1 yr., SD = 12.3) for odor intensity, gender association (masculine/feminine), and the success, sociability, intelligence, cleanliness, and attractiveness of a hypothetical person whose clothes smell like the odor in question. Ratings of the pleasantness or unpleasantness one would attribute to each odor in various rooms of the home were obtained, as well as a specification of whether such ratings are influenced by laundry habits, e.g., whether laundry is smelled before or after washing. Numerous associations were found. For example, a hypothetical person whose clothes smell of pine was rated as relatively more successful, intelligent, sociable, sanitary, and attractive than one whose clothes smelled of lemon, onion, or smoke. Sex differences, as well as differences between people who reported smelling their own laundry, were also found. PMID:15773704

  15. Odor investigation of a Portland cement plant

    SciTech Connect

    Pleus, R.C.

    1998-12-31

    The main concern expressed by Smithville residents is whether the odors they were smelling during odor events were due to chemicals that could cause adverse health effects. Odors were allegedly emanating from the town`s Portland cement plant. The purpose of the study was to measure the ambient air for 20 reduced sulfur, 50 volatile organic compounds, and air samples for olfactometric analysis. Carbonyl sulfide was found to be at a concentration that could create a sense of odor and irritation. This sense of irritation may be due to a physiological response by the central nervous system, and is not associated with any known adverse effects. This physiological response could account for some or all of the irritation experienced by residents during odor events. Comparing chemical concentrations that were detected in air samples to standard and recognized guidelines for acceptable exposure, all measured concentrations were found to be well below the acceptable criteria. From these data the authors conclude that no acute or chronic adverse health effects are expected at the concentrations of the chemicals detected downwind of the cement plant, either routinely or during odor events.

  16. Canine detection odor signatures for explosives

    NASA Astrophysics Data System (ADS)

    Williams, Marc; Johnston, J. M.; Cicoria, Matt; Paletz, E.; Waggoner, L. Paul; Edge, Cindy C.; Hallowell, Susan F.

    1998-12-01

    Dogs are capable of detecting and discriminating a number of compounds constituting a complex odor. However, they use only a few of these to recognize a substance. The focus of this research is to determine the compounds dogs learn to use in recognizing explosives. This is accomplished by training dogs under behavioral laboratory conditions to respond differentially on separate levers to 1) blank air, 2) a target odor, such as an explosive, and 3) all other odors (non-target odors). Vapor samples are generated by a serial dilution vapor generator whose operation and output is characterized by GC/MS. Once dogs learn this three-lever discrimination, testing sessions are conducted containing a number of probe trials in which vapor from constituent compounds of the target is presented. Which lever the dogs respond to on these probe trials indicates whether they can smell the compound at all (blank lever) or whether it smells like toe target odor (e.g., the explosive) or like something else. This method was conducted using TNT, C-4, and commercial dynamite. The data show the dogs' reactions to each of the constituent compounds tested for each explosive. Analysis of these data reveal the canine detection odor signature for these explosives.

  17. 7 CFR 51.574 - Green.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Green. 51.574 Section 51.574 Agriculture Regulations... FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Celery Definitions § 51.574 Green. Green means that the middle portions of the outer...

  18. 7 CFR 51.574 - Green.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Green. 51.574 Section 51.574 Agriculture Regulations... FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Celery Definitions § 51.574 Green. Green means that the middle portions of the outer...

  19. A fruity note: crossmodal associations between odors and musical notes.

    PubMed

    Crisinel, Anne-Sylvie; Spence, Charles

    2012-02-01

    Odors are notoriously difficult to describe, but they seem prone to a variety of crossmodal associations. In the present study, we generalize the previously-shown association between odors (from perfumery) and pitch (Belkin et al. 1997) to odors related to food and drink (in this case those associated with wine). We also demonstrate that, to a lesser extent (25% of the odor tested), participants preferentially match specific odors to certain types of instruments. The ratings of the odors along a number of dimensions are used in principal components analysis (PCA) to explore the psychological dimensions underlying the odor-pitch associations. The results demonstrate that both pleasantness and complexity, but not intensity, appear to play a role when choosing a pitch to match an odor. Our results suggest that these features of odor stimuli constitute psychological dimensions that can be consistently matched to auditory features. PMID:21852708

  20. Robust and Rapid Air-Borne Odor Tracking without Casting.

    PubMed

    Bhattacharyya, Urvashi; Bhalla, Upinder Singh

    2015-01-01

    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

  1. Novel methods to assess the influence of diet and incubation time on the emissions of odors from beef and swine manures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The influence of diet type and time of incubation (fresh vs. overnight) on the emissions of odors from the feces of beef cattle and swine was evaluated by gas chromatography-mass spectral (GC-MS) analysis. Swine (n=12) and beef cattle (n=24) were fed with two and four separate diets, respectively (n...

  2. Neonatal Odor-Shock Conditioning Alters the Neural Network Involved in Odor Fear Learning at Adulthood

    ERIC Educational Resources Information Center

    Sevelinges, Yannick; Sullivan, Regina M.; Messaoudi, Belkacem; Mouly, Anne-Marie

    2008-01-01

    Adult learning and memory functions are strongly dependent on neonatal experiences. We recently showed that neonatal odor-shock learning attenuates later life odor fear conditioning and amygdala activity. In the present work we investigated whether changes observed in adults can also be observed in other structures normally involved, namely…

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  4. International comparison of odor threshold values of several odorants in Japan and in The Netherlands.

    PubMed

    Hoshika, Y; Imamura, T; Muto, G; Van Gemert, L J; Don, J A; Walpot, J I

    1993-04-01

    The purpose of this paper is to compare the published odor threshold values of six odorants. In Japan, all of the odor threshold values used in the Offensive Odor Control Law (enacted in 1972) were determined in an odor-free room (4 m3) by a trained panel (20 men, ages 30-45 years who were perfumers) who sniffed the odors directly and made absolute judgments of odor quality and intensity. In The Netherlands, sensorial odor concentration measurements were made with an olfactometer in a mobile sniffing car with eight panelists, four men and four women, ages 18-40 years. Such presentations are repeated with different dilution ratios. Comparison of the threshold data for the six different compounds given as the barely perceptible concentration level revealed striking similarities for hydrogen sulfide (in Japan 0.0005 ppm/in The Netherlands 0.0003 ppm), phenol (0.012/0.010), styrene (0.033/0.016), toluene (0.92/0.99), and tetrachloroethylene (1.8/1.2) but not for m-xylene (0.012/0.12). Such a similarity was not found with any other literature sources. PMID:8472679

  5. Direct nuclear magnetic resonance observation of odorant binding to mouse odorant receptor MOR244-3.

    PubMed

    Burger, Jessica L; Jeerage, Kavita M; Bruno, Thomas J

    2016-06-01

    Mammals are able to perceive and differentiate a great number of structurally diverse odorants through the odorant's interaction with odorant receptors (ORs), proteins found within the cell membrane of olfactory sensory neurons. The natural gas industry has used human olfactory sensitivity to sulfur compounds (thiols, sulfides, etc.) to increase the safety of fuel gas transport, storage, and use through the odorization of this product. In the United States, mixtures of sulfur compounds are used, but the major constituent of odorant packages is 2-methylpropane-2-thiol, also known as tert-butyl mercaptan. It has been fundamentally challenging to understand olfaction and odorization due to the low affinity of odorous ligands to the ORs and the difficulty in expressing a sufficient number of OR proteins. Here, we directly observed the binding of tert-butyl mercaptan and another odiferous compound, cis-cyclooctene, to mouse OR MOR244-3 on living cells by saturation transfer difference (STD) nuclear magnetic resonance (NMR) spectroscopy. This effort lays the groundwork for resolving molecular mechanisms responsible for ligand binding and resulting signaling, which in turn will lead to a clearer understanding of odorant recognition and competition. PMID:27019154

  6. Feasibility Study of Odor Biosensor Using Dissociate Neuronal Culture with Gene Expression of Ionotropic Odorant Receptors

    NASA Astrophysics Data System (ADS)

    Tanada, Norio; Sakurai, Takeshi; Mitsuno, Hidefumi; Bakkum, Douglas; Kanzaki, Ryohei; Takahashi, Hirokazu

    We propose a highly sensitive and real-time odor biosensor by expressing ionotropic odorant receptors of insects into dissociated cultures of neurons of rats. The odorant-gated ion channel structure of insect odorant receptor is expected to allow easy functional expression into cells. The neuronal dissociated cultures of rats have two significant advantages: a long lifetime comparable to rats, i.e., a few years; and amplification ability from weak ionic currents of odorant receptors into easily detectable action potentials of neurons. In the present work, in order to show the feasibility of the proposed sensor, we attempt to express the pheromone receptors of silkmoth, Bombyx mori, into cultured neurons of rats. We demonstrate that 10% of neuronal cells transfected using Lipofectamine successfully expressed pheromone receptors, and that these cells showed significant increase of calcium signals by 50% at the presentation of pheromone.

  7. Fresh Water Life.

    ERIC Educational Resources Information Center

    Kestler, Carol Susan

    1991-01-01

    Describes methodology for a fresh water life study with elementary through college age students with suggestions for proper equipment, useful guides, and other materials. Proposes an activity for the collection and study of plankton. Includes background information.(MCO)

  8. Natural gas odor level testing: Instruments and applications

    SciTech Connect

    Roberson, E.H.

    1995-12-01

    An odor in natural and LP gases is necessary. The statistics are overwhelming; when gas customers can smell a leak before the percentage of gas in air reaches a combustible mixture, the chances of an accident are greatly reduced. How do gas companies determine if there is sufficient odor reaching every gas customers home? Injection equipment is important. The rate and quality of odorant is important. Nevertheless, precision odorization alone does not guarantee that customers` homes always have gas with a readily detectable odor. To secure that goal, odor monitoring instruments are necessary.

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

    NASA Astrophysics Data System (ADS)

    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.

  10. Expression Patterns of Odorant Receptors and Response Properties of Olfactory Sensory Neurons in Aged Mice

    PubMed Central

    Lee, Anderson C.; Tian, Huikai; Grosmaitre, Xavier

    2009-01-01

    The sense of smell deteriorates in normal aging, but the underling mechanisms are still elusive. Here we investigated age-related alterations in expression patterns of odorant receptor (OR) genes and functional properties of olfactory sensory neurons (OSNs)—2 critical factors that define the odor detection threshold in the olfactory epithelium. Using in situ hybridization for 9 representative OR genes, we compared the cell densities of each OR in coronal nose sections at different ages (3–27 months). The cell density for different ORs peaked at different time points and a decline was observed for 6 of 9 ORs at advanced ages. Using patch clamp recordings, we then examined the odorant responses of individual OSNs coexpressing a defined OR (MOR23) and green fluorescent protein. The MOR23 neurons recorded from aged animals maintained a similar sensitivity and dynamic range in response to the cognate odorant (lyral) as those from younger mice. The results indicate that although the cell densities of OSNs expressing certain types of ORs decline at advanced ages, individual OSNs can retain their sensitivity. The implications of these findings in age-related olfactory deterioration are discussed. PMID:19759360

  11. Food odors trigger Drosophila males to deposit a pheromone that guides aggregation and female oviposition decisions

    PubMed Central

    Lin, Chun-Chieh; Prokop-Prigge, Katharine A; Preti, George; Potter, Christopher J

    2015-01-01

    Animals use olfactory cues for navigating complex environments. Food odors in particular provide crucial information regarding potential foraging sites. Many behaviors occur at food sites, yet how food odors regulate such behaviors at these sites is unclear. Using Drosophila melanogaster as an animal model, we found that males deposit the pheromone 9-tricosene upon stimulation with the food-odor apple cider vinegar. This pheromone acts as a potent aggregation pheromone and as an oviposition guidance cue for females. We use genetic, molecular, electrophysiological, and behavioral approaches to show that 9-tricosene activates antennal basiconic Or7a receptors, a receptor activated by many alcohols and aldehydes such as the green leaf volatile E2-hexenal. We demonstrate that loss of Or7a positive neurons or the Or7a receptor abolishes aggregation behavior and oviposition site-selection towards 9-tricosene and E2-hexenal. 9-Tricosene thus functions via Or7a to link food-odor perception with aggregation and egg-laying decisions. DOI: http://dx.doi.org/10.7554/eLife.08688.001 PMID:26422512

  12. Identifying and tracking key odorants from cattle feedlots

    NASA Astrophysics Data System (ADS)

    Trabue, Steven; Scoggin, Kenwood; McConnell, Laura; Maghirang, Ronaldo; Razote, Edna; Hatfield, Jerry

    2011-08-01

    Odors from cattle feedlots can negatively affect air quality in local communities. Our objectives were the following: 1) identify key odor-causing compounds using odor activity values (OAVs) and gas chromatography-olfactometry (GC-O) techniques; 2) compare odor threshold values from published databases; and 3) track the movement of odors from a cattle feedlot to receptor community. Odorous compounds emitted from a cattle feedlot were sampled on-site, 250 m downwind and 3.2 km downwind using both sorbent tubes and denuders. Sorbent tubes were analyzed by both GC-MS and GC-MS-O and key odorants determined using both OAV and GC-Surface Nasal Impact Frequency (SNIF) analysis, while denuders were analyzed by ion chromatography. Odorant concentrations had a diurnal pattern with peak concentrations during early morning and late evening periods. Volatile fatty acids (VFAs) were the most abundant of the major odorants. Odorants with concentrations above their odor threshold values at the feedlot included amines, VFAs, phenol compounds, and indole compounds. Key odorants at the feedlot were VFAs and phenol compounds, but their relative importance diminished with downwind distance. Indole compounds, while not the key odorants at the feedlot, increased in relative importance downwind of the feedlot. In general, the odorous compounds identified by GC-SNIF and OAV as having fecal/manure nature were similar. GC-SNIF was the more sensitive analytical technique; it identified several compounds that may have contributed to the unpleasantness of the cattle feedlot odor, but its throughput was extremely low thereby limiting its usefulness. There is a need to improve field sampling devices and odor threshold databases to enhance understanding and confidence in evaluating odors.

  13. The Influence of Odors on Time Perception

    PubMed Central

    Millot, Jean-Louis; Laurent, Lucie; Casini, Laurence

    2016-01-01

    The effect of an olfactory stimulation on the perception of time was investigated through two different experiments based on temporal bisection tasks. In experiment 1, the durations to be classified as either short or long were centered on 400 ms while in Experiment 2 there were centered on 2000 ms. The participants were different in the two experiments (36 subjects in each one). In each experiment, half of the subjects learnt the anchor durations when smelling an unpleasant odor (decanoic acid) and the other half when smelling no odor. After the learning phase, both groups were tested with and without odor. The results showed opposite effects depending on the duration range. The subjects underestimated the time in the presence of the unpleasant odor in the short duration range while they overestimated it in the long duration range. The results have been discussed in the framework of the pacemaker-counter clock model and a potential emotional effect induced by the odor on the subjective time perception has also been considered. PMID:26925008

  14. How do mice follow odor trails?

    NASA Astrophysics Data System (ADS)

    Zwicker, David; Trastour, Sophie; Mishra, Shruti; Mathis, Alexander; Murthy, Venkatesh; Brenner, Michael P.

    2015-11-01

    Mice are excellent at following odor trails e.g. to locate food or to find mates. However, it is not yet understood what navigation strategies they use. In principle, they could either evaluate temporal differences between sniffs or they could use concurrent input from the two nostrils. It is unknown to what extend these two strategies contribute to mice's performance. When mice follow trails, odors evaporate from the ground, are transported by flow in the air, and are then inhaled with the two nostrils. In order to differentiate between the two navigation strategies, we determine what information the mouse receives: first, we calculate the airflow by numerically solving the incompressible Navier-Stokes equations. We then determine the spatiotemporal odor concentration from the resulting advection-diffusion equations. Lastly, we determine the odor amount in each nostril by calculating the inhalation volumes using potential flow theory. Taken together, we determine the odor amount in each nostril during each sniff, allowing a detailed study of navigation strategies.

  15. [Odor sensing system and olfactory display].

    PubMed

    Nakamoto, Takamichi

    2014-01-01

    In this review, an odor sensing system and an olfactory display are introduced into people in pharmacy. An odor sensing system consists of an array of sensors with partially overlapping specificities and pattern recognition technique. One of examples of odor sensing systems is a halitosis sensor which quantifies the mixture composition of three volatile sulfide compounds. A halitosis sensor was realized using a preconcentrator to raise sensitivity and an electrochemical sensor array to suppress the influence of humidity. Partial least squares (PLS) method was used to quantify the mixture composition. The experiment reveals that the sufficient accuracy was obtained. Moreover, the olfactory display, which present scents to human noses, is explained. A multi-component olfactory display enables the presentation of a variety of smells. The two types of multi-component olfactory display are described. The first one uses many solenoid valves with high speed switching. The valve ON frequency determines the concentration of the corresponding odor component. The latter one consists of miniaturized liquid pumps and a surface acoustic wave (SAW) atomizer. It enables the wearable olfactory display without smell persistence. Finally, the application of the olfactory display is demonstrated. Virtual ice cream shop with scents was made as a content of interactive art. People can enjoy harmony among vision, audition and olfaction. In conclusion, both odor sensing system and olfactory display can contribute to the field of human health care. PMID:24584010

  16. Sensing odorants and pheromones with chemosensory receptors.

    PubMed

    Touhara, Kazushige; Vosshall, Leslie B

    2009-01-01

    Olfaction is a critical sensory modality that allows living things to acquire chemical information from the external world. The olfactory system processes two major classes of stimuli: (a) general odorants, small molecules derived from food or the environment that signal the presence of food, fire, or predators, and (b) pheromones, molecules released from individuals of the same species that convey social or sexual cues. Chemosensory receptors are broadly classified, by the ligands that activate them, into odorant or pheromone receptors. Peripheral sensory neurons expressing either odorant or pheromone receptors send signals to separate odor- and pheromone-processing centers in the brain to elicit distinct behavioral and neuroendocrinological outputs. General odorants activate receptors in a combinatorial fashion, whereas pheromones activate narrowly tuned receptors that activate sexually dimorphic neural circuits in the brain. We review recent progress on chemosensory receptor structure, function, and circuitry in vertebrates and invertebrates from the point of view of the molecular biology and physiology of these sensory systems. PMID:19575682

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

    PubMed

    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). PMID:27086994

  18. Irradiation of Fresh and Fresh-Cut Fruits and Vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consumption of fresh and fresh-cut fruits and vegetables in the USA has increased every year in the last decade. Unfortunately, the increasing consumption of fresh produce has been accompanied with an increase in the number of outbreaks and recalls due to contamination with human pathogens. Fresh f...

  19. Odors Pulsed at Wing Beat Frequencies are Tracked by Primary Olfactory Networks and Enhance Odor Detection

    PubMed Central

    Tripathy, Shreejoy J.; Peters, Oakland J.; Staudacher, Erich M.; Kalwar, Faizan R.; Hatfield, Mandy N.; Daly, Kevin C.

    2009-01-01

    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 (200 μM) 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. PMID:20407584

  20. Odor-identity dependent motor programs underlie behavioral responses to odors

    PubMed Central

    Jung, Seung-Hye; Hueston, Catherine; Bhandawat, Vikas

    2015-01-01

    All animals use olfactory information to perform tasks essential to their survival. Odors typically activate multiple olfactory receptor neuron (ORN) classes and are therefore represented by the patterns of active ORNs. How the patterns of active ORN classes are decoded to drive behavior is under intense investigation. In this study, using Drosophila as a model system, we investigate the logic by which odors modulate locomotion. We designed a novel behavioral arena in which we could examine a fly’s locomotion under precisely controlled stimulus condition. In this arena, in response to similarly attractive odors, flies modulate their locomotion differently implying that odors have a more diverse effect on locomotion than was anticipated. Three features underlie odor-guided locomotion: First, in response to odors, flies modulate a surprisingly large number of motor parameters. Second, similarly attractive odors elicit changes in different motor programs. Third, different ORN classes modulate different subset of motor parameters. DOI: http://dx.doi.org/10.7554/eLife.11092.001 PMID:26439011

  1. A Review of Trimethylaminuria: (Fish Odor Syndrome)

    PubMed Central

    Messenger, Jeffrey; Clark, Shane; Massick, Susan

    2013-01-01

    Trimethylaminuria, better known as fish odor syndrome, is a psychologically disabling condition in which a patient emits a foul odor, which resembles that of rotting fish. The disorder is most commonly caused by an inherited deficiency in flavin monooxygenase 3, the vital enzyme for the metabolism of trimethylamine, which is the compound responsible for the unpleasant odor. The condition is uncommon, but there has been recent research to suggest that the diagnosis may often be overlooked. Moreover, it is important to be cognizant of this condition because there are reliable diagnostic tests and the disorder can be devastating from a psychosocial perspective. While there is no cure, many simple treatment options exist that may drastically improve the quality of life of these patients. This article will review the literature with an emphasis on the psychosocial impact and treatment options. PMID:24307925

  2. Guidance by odors in honeybee navigation.

    PubMed

    Menzel, Randolf; Greggers, Uwe

    2013-10-01

    Animal navigation is guided by multiple sensory cues. Here, we ask whether and how olfactory stimuli emanating from places other than the trained feeding site redirect the flight paths of honeybees. The flight trajectories of individual bees were registered using harmonic radar tracking. Sensory cues (compass direction, distance, visual cues en route and close to the feeding site) associated with the trained flight route dominated wayfinding, but a learned odorant carried by air flow induced excursions into the wind. These redirections were largely restricted to rather small deviations from the trained route (<60°, <200 m) and occurred only if the animal did not receive the trained odorant stimulus at the trained feeding site. Under certain conditions, larger excursions were observed. These findings are discussed in the context of odor guidance of honeybees over longer distances (>300 m from the hive). PMID:23974855

  3. The spatial distributions of odorant sensitivity and odorant-induced currents in salamander olfactory receptor cells.

    PubMed Central

    Lowe, G; Gold, G H

    1991-01-01

    1. Suction electrode and whole-cell recording were used to record membrane currents from defined regions of solitary olfactory receptor cells from Ambystoma tigrinum. 2. Under whole-cell current clamp, stimulation of cells with odorants activated an inward current in the cilia, an outward current in the soma, and induced a membrane depolarization. Clamping the membrane potential at its resting value of -70 mV increased the inward ciliary current 5- to 10-fold and abolished the outward somatic current. 3. Local odorant stimulation was accomplished by ejecting an odorant solution into a steady flow of Ringer solution. A suction electrode was used to immobilize a cell in the flow and to record the odorant-induced somatic current. The amplitude of the odorant response increased approximately linearly with the length of cilia exposed to the stimulus, but was independent of the length of dendrite exposed to the stimulus, indicating that odorant sensitivity is predominantly localized to the cilia. 4. The latencies of responses recorded under flow did not vary with the region of the cilia which was exposed to the stimulus. Also, the magnitude of the inward ciliary current activated by odorants was equal to that of the whole-cell current recorded under voltage clamp. These observations indicate that the odorant-induced inward current is predominantly localized to the ciliary membrane. 5. Under whole-cell current clamp, local application of a high-K+ solution generated an outward somatic current when applied to the dendrite, but had no effect when applied to the cilia. This indicates that the density of the resting K+ conductance is lower in the ciliary membrane than in the dendritic membrane. 6. The results above are consistent with the hypothesis that all components of the transduction mechanism are uniformly distributed within the cilia, and that the cilia are electrotonically compact, even during an odorant-induced conductance increase. Images Fig. 2 PMID:1798028

  4. Ventilation requirements for control of occupancy odor and tobacco smoke odor: laboratory studies. Final report

    SciTech Connect

    Cain, W.S.; Isseroff, R.; Leaderer, B.P.; Lipsitt, E.D.; Huey, R.J.; Perlman, D.; Bergland, L.G.; Dunn, J.D.

    1981-04-01

    Experiments on occupancy odor addressed the question of why required ventilation rate per occupant increased progressively with increases in the number of persons in a space. In order to investigate ventilation requirements under approximately ideal conditions, we constructed an aluminum-lined environmental chamber with excellent control over environmental conditions and a ventilation system that provided rapid and uniform mixing of air. Psychophysical experiments on occupancy odor explored 47 different combinations of occupancy density, temperature and humidity, and ventilation rate. The experiments collected judgements both from visitors, who smelled air from the chamber only once every few minutes, and from occupants, who remained in the chamber for an hour at a time. The judgements of visitors revealed that occupancy odor increased only gradually over time and rarely reached very high or objectionable levels. Judgements of occupants also revealed rather minor dissatisfaction. Only during combinations of high temperature and humidity did objectionability become more than a minor issue to either group. Experiments on cigarette smoking explored rates of 4, 8, and 16 cigarettes per hour under various environmental conditions and with ventilation rates as high as 68 cfm (34 L.s/sup -1/) per occupant. As soon as occupants lit cigarettes in the chamber, the odor level increased dramatically. At ventilation rates far greater than necessary to control occupancy odor, the odor from cigarette smoking remained quite intense. In general, the odor proved impossible to control adequately even with a ventilation rate of 68 cfm (34 L.s/sup -1/) per occupant (4 occupants) and even when only one occupant smoked at a time. As in the case of occupancy odor, a combination of high temperature and humidity exacerbated the odor problem.

  5. Sampling Odor Substances by Mist-Cyclone System

    NASA Astrophysics Data System (ADS)

    Matsubara, Osamu; Jiang, Zhiheng; Toyama, Shigeki

    2009-05-01

    Many techniques have been developed to measure odor substances. However most of those methods are based on using aquatic solutions(1),(2). Many odor substances specifically at low density situation, are difficult to dissolve into water. To absorb odor substances and obtain highest concentration solutions are key problems for olfactory systems. By blowing odor substances contained air mixture through mist of water and then separating the liquid from two-phases fluid with a cyclone unit a high concentration solution was obtained.

  6. Odor-taste interactions: effects of attentional strategies during exposure.

    PubMed

    Prescott, John; Johnstone, Victoria; Francis, Joanne

    2004-05-01

    Through repeated pairings with a tastant such as sucrose, odors are able to take on the tastant's qualities, e.g. by becoming more sweet smelling. When such odors are subsequently experienced with a sweet tastant in solution, the mixture is often given a higher sweetness rating than the tastant alone. Odor-induced taste enhancement appears to be sensitive to whether an odor-taste combination is viewed analytically as a set of discrete qualities, or synthetically as a flavor. The present research attempted to determine if adoption of these different perceptual approaches during co-exposure with sucrose would influence the extent to which an odor would become sweet smelling and subsequently enhance sweetness intensity. In Experiment 1, subjects received multiple exposures to mixtures of sucrose with low sweetness, low familiarity odors or, as a control, the odors and sucrose solutions separately. Two groups that received mixtures made intensity ratings that promoted either synthesis or analysis of the individual elements in the mixtures. The odors became sweeter smelling irrespective of group. Only adopting a synthetic strategy produced odors that enhanced sweetness in solution. However, these effects were also shown with a 'non-exposed' control odor. This could be accounted for if the single co-exposure with sucrose that all odors received in the pre-test was able to produce sweeter odors. A second experiment confirmed this prediction. Thus, while even a single co-exposure with sucrose is sufficient to produce a sweeter odor, the adoption of a synthetic perceptual strategy during the co-exposure is necessary to produce an odor that will enhance sweetness. These data are consistent with associative leaning accounts of how odors take on taste qualities and also support the interpretation that these effects reflect the central integration of odors and tastes into flavors. PMID:15150146

  7. Testing for odor discrimination and habituation in mice.

    PubMed

    Arbuckle, Erin P; Smith, Gregory D; Gomez, Maribel C; Lugo, Joaquin N

    2015-01-01

    This video demonstrates a technique to establish the presence of a normally functioning olfactory system in a mouse. The test helps determine whether the mouse can discriminate between non-social odors and social odors, whether the mouse habituates to a repeatedly presented odor, and whether the mouse demonstrates dishabituation when presented with a novel odor. Since many social behavior tests measure the experimental animal's response to a familiar or novel mouse, false positives can be avoided by establishing that the animals can detect and discriminate between social odors. There are similar considerations in learning tests such as fear conditioning that use odor to create a novel environment or olfactory cues as an associative stimulus. Deficits in the olfactory system would impair the ability to distinguish between contexts and to form an association with an olfactory cue during fear conditioning. In the odor habitation/dishabituation test, the mouse is repeatedly presented with several odors. Each odor is presented three times for two minutes. The investigator records the sniffing time directed towards the odor as the measurement of olfactory responsiveness. A typical mouse shows a decrease in response to the odor over repeated presentations (habituation). The experimenter then presents a novel odor that elicits increased sniffing towards the new odor (dishabituation). After repeated presentation of the novel odor the animal again shows habituation. This protocol involves the presentation of water, two or more non-social odors, and two social odors. In addition to reducing experimental confounds, this test can provide information on the function of the olfactory systems of new knockout, knock-in, and conditional knockout mouse lines. PMID:25992586

  8. Selectivity of odorant receptors in insects

    PubMed Central

    Bohbot, Jonathan D.; Dickens, Joseph C.

    2012-01-01

    Insect olfactory receptors (ORs) detect chemicals, shape neuronal physiology, and regulate behavior. Although ORs have been categorized as “generalists” and “specialists” based on their ligand spectrum, both electrophysiological studies and recent pharmacological investigations show that ORs specifically recognize non-pheromonal compounds, and that our understanding of odorant-selectivity mirrors our knowledge of insect chemical ecology. As we are progressively becoming aware that ORs are activated through a variety of mechanisms, the molecular basis of odorant-selectivity and the corollary notion of broad-tuning need to be re-examined from a pharmacological and evolutionary perspective. PMID:22811659

  9. 9 CFR 311.37 - Odors, foreign and urine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Odors, foreign and urine. 311.37..., foreign and urine. (a) Carcasses which give off a pronounced odor of medicinal, chemical, or other foreign substance shall be condemned. (b) Carcasses which give off a pronounced urine odor shall be condemned....

  10. 9 CFR 311.37 - Odors, foreign and urine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Odors, foreign and urine. 311.37..., foreign and urine. (a) Carcasses which give off a pronounced odor of medicinal, chemical, or other foreign substance shall be condemned. (b) Carcasses which give off a pronounced urine odor shall be condemned....

  11. 9 CFR 311.37 - Odors, foreign and urine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Odors, foreign and urine. 311.37..., foreign and urine. (a) Carcasses which give off a pronounced odor of medicinal, chemical, or other foreign substance shall be condemned. (b) Carcasses which give off a pronounced urine odor shall be condemned....

  12. 9 CFR 311.37 - Odors, foreign and urine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Odors, foreign and urine. 311.37..., foreign and urine. (a) Carcasses which give off a pronounced odor of medicinal, chemical, or other foreign substance shall be condemned. (b) Carcasses which give off a pronounced urine odor shall be condemned....

  13. 9 CFR 311.37 - Odors, foreign and urine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Odors, foreign and urine. 311.37..., foreign and urine. (a) Carcasses which give off a pronounced odor of medicinal, chemical, or other foreign substance shall be condemned. (b) Carcasses which give off a pronounced urine odor shall be condemned....

  14. Identifying Key Odors Offsite From Animal Feeding Operation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Odors from animal feeding operations are some of the most significant emissions at the local level. Current methods used to measure agricultural odor are bias and inadequate. The purpose of this study was to evaluate the ability of 2 different techniques to identify key odorants. The first techni...

  15. Graded Encoding of Food Odor Value in the Drosophila Brain

    PubMed Central

    Beshel, Jennifer

    2013-01-01

    Odors are highly evocative, yet how and where in the brain odors derive meaning remains unknown. Our analysis of the Drosophila brain extends the role of a small number of hunger-sensing neurons to include food-odor value representation. In vivo two-photon calcium imaging shows the amplitude of food odor-evoked activity in neurons expressing Drosophila neuropeptide F (dNPF), the neuropeptide Y homolog, strongly correlates with food-odor attractiveness. Hunger elevates neural and behavioral responses to food odors only, although food odors that elicit attraction in the fed state also evoke heightened dNPF activity in fed flies. Inactivation of a subset of dNPF-expressing neurons or silencing dNPF receptors abolishes food-odor attractiveness, whereas genetically enhanced dNPF activity not only increases food-odor attractiveness but promotes attraction to aversive odors. Varying the amount of presented odor produces matching graded neural and behavioral curves, which can function to predict preference between odors. We thus demonstrate a possible motivationally scaled neural “value signal” accessible from uniquely identifiable cells. PMID:24089477

  16. Animal Emissions Analyzed by both Chemical and Odor Panel Methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The National Research Council identified odors as the most significant animal emission at the local level and highlighted the need for the development of standardized protocols for sampling and analysis of odors. In this study, odorous air from a swine facility was analyzed by both human panels an...

  17. Multimodal integration: Visual cues helps odor-seeking fruit flies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent studies have shown that integration of sensory modalities is critical to the process of odor-source location. Attractive food odors initiate flies’ response to visual cues to maintain narrow angle turns with respect to the wind line; loss of odor contact due to idiothetic motion or experimen...

  18. Comparison of three lychee cultivar odor profiles using gas chromatography-olfactometry and gas chromatography-sulfur detection.

    PubMed

    Mahattanatawee, Kanjana; Perez-Cacho, Pilar Ruiz; Davenport, Thomas; Rouseff, Russell

    2007-03-01

    Odor volatiles in three major lychee cultivars (Mauritius, Brewster, and Hak Ip) were examined using gas chromatography-olfactometry, gas chromatography-mass spectrometry, and gas chromatography-pulsed flame photometric detection. Fifty-nine odor-active compounds were observed including 11 peaks, which were associated with sulfur detector responses. Eight sulfur volatiles were identified as follows: hydrogen sulfide, dimethyl sulfide, diethyl disulfide, 2-acetyl-2-thiazoline, 2-methyl thiazole, 2,4-dithiopentane, dimethyl trisulfide, and methional. Mauritius contained 25% and Brewster contained 81% as much total sulfur volatiles as Hak Ip. Cultivars were evaluated using eight odor attributes: floral, honey, green/woody, tropical fruit, peach/apricot, citrus, cabbage, and garlic. Major odor differences in cabbage and garlic attributes correlated with cultivar sulfur volatile composition. The 24 odor volatiles common to all three cultivars were acetaldehyde, ethanol, ethyl-3-methylbutanoate, diethyl disulfide, 2-methyl thiazole, 1-octen-3-one, cis-rose oxide, hexanol, dimethyl trisulfide, alpha-thujone, methional, 2-ethyl hexanol, citronellal, (E)-2-nonenal, linalool, octanol, (E,Z)-2,6-nonadienal, menthol, 2-acetyl-2-thiazoline, (E,E)-2,4-nonadienal, beta-damascenone, 2-phenylethanol, beta-ionone, and 4-vinyl-guaiacol. PMID:17266328

  19. Behavioral Responses to Mammalian Blood Odor and a Blood Odor Component in Four Species of Large Carnivores

    PubMed Central

    Nilsson, Sara; Sjöberg, Johanna; Amundin, Mats; Hartmann, Constanze; Buettner, Andrea; Laska, Matthias

    2014-01-01

    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

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

    PubMed

    Nilsson, Sara; Sjöberg, Johanna; Amundin, Mats; Hartmann, Constanze; Buettner, Andrea; Laska, Matthias

    2014-01-01

    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 enrichment

  1. Characterization of the Major Odor-Active Compounds in the Leaves of the Curry Tree Bergera koenigii L. by Aroma Extract Dilution Analysis.

    PubMed

    Steinhaus, Martin

    2015-04-29

    Curry leaves are a popular seasoning herb with a pronounced sulfury and burnt odor, the molecular background of which was yet unclear. Application of an aroma extract dilution analysis to the volatile fraction of curry leaves isolated by solvent extraction and solvent-assisted flavor evaporation afforded 23 odor-active compounds with flavor dilution (FD) factors ranging from 1 to 8192. On the basis of the comparison of their retention indices, mass spectra, and odor properties with data of reference compounds, the structures of 22 odorants could be assigned, 15 of which had not been reported in curry leaves before. Odorants with high FD factors included 1-phenylethanethiol (FD factor 8192), linalool (4096), α-pinene (2048), 1,8-cineole (1024), (3Z)-hex-3-enal (256), 3-(methylsulfanyl)propanal (128), myrcene (64), (3Z)-hex-3-en-1-ol (32), and (2E,6Z)-nona-2,6-dienal (32). The unique sulfury and burnt odor exhibited by 1-phenylethanethiol in combination with its high FD factor suggested that it constitutes the character impact compound of fresh curry leaf aroma. PMID:25857926

  2. Shop Around for Freshness.

    ERIC Educational Resources Information Center

    Evans, George P.

    1998-01-01

    Argues that cliches make writing stale and flat, and that getting rid of them is a necessity. Lists the "top 14" cliches gathered by a Columbia Scholastic Press Association judge. Uses examples to show how cleansing a passage of its superlatives and cliches improves the writing, adding clarity, fairness, and objectivity as well as freshness and…

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

    PubMed Central

    Thomas-Danguin, Thierry; Sinding, Charlotte; Romagny, Sébastien; El Mountassir, Fouzia; Atanasova, Boriana; Le Berre, Elodie; Le Bon, Anne-Marie; Coureaud, Gérard

    2014-01-01

    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. PMID:24917831

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

    PubMed Central

    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

  5. Effect of odor preexposure on acquisition of an odor discrimination in dogs.

    PubMed

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

    2014-06-01

    In two experiments, we investigated the impact of odor preexposure treatments on the acquisition of an olfactory discrimination in dogs. In the first experiment, four groups of dogs were each given five days' odor-exposure treatment prior to discrimination training. Dogs in the exposure group were exposed to anise extract (S+) for 30 min daily. Dogs in the Pavlovian-relevant pairing group received six daily delayed-conditioning trials to the same S+. The Pavlovian-irrelevant pairing group received conditioning trials to almond extract (S'). Dogs in the control group received no pretreatment. All of the dogs were then trained to detect S+ from a background pine odor (an AX-vs.-X discrimination). The Pavlovian-relevant pairing group acquired the odor discrimination significantly faster than all of the other exposure and control groups, and the remaining groups acquired the discrimination at the same rate as the no-exposure control group. In a second experiment, we extended these results to a within-subjects design using an AX-versus-BX discrimination. Six dogs were simultaneously trained on two different odor discriminations, one discrimination in which the S+ was previously Pavlovian conditioned, and one discrimination in which the S+ was novel. All of the dogs learned the odor discrimination with the previously conditioned S+ faster than they learned the novel odor discrimination, replicating the results of Experiment 1, and demonstrating that familiarity in the form of Pavlovian conditioning enhances odor-discrimination training. The potential mechanisms of the facilitated transfer of a Pavlovian conditioned stimulus to discrimination training are discussed. PMID:24464655

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

    PubMed

    Thomas-Danguin, Thierry; Sinding, Charlotte; Romagny, Sébastien; El Mountassir, Fouzia; Atanasova, Boriana; Le Berre, Elodie; Le Bon, Anne-Marie; Coureaud, Gérard

    2014-01-01

    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. PMID:24917831

  7. Controlling Swine Odor with Natural Windbreaks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Emissions of malodor from swine facilities are an increasing environmental concern for swine producers and nearby local communities. Use of natural windbreaks for odor abatement is recent and the science in support of using windbreaks for this purpose is limited. To provide sound science to the stu...

  8. Odor Impression Prediction from Mass Spectra

    PubMed Central

    Nakamoto, Takamichi

    2016-01-01

    The sense of smell arises from the perception of odors from chemicals. However, the relationship between the impression of odor and the numerous physicochemical parameters has yet to be understood owing to its complexity. As such, there is no established general method for predicting the impression of odor of a chemical only from its physicochemical properties. In this study, we designed a novel predictive model based on an artificial neural network with a deep structure for predicting odor impression utilizing the mass spectra of chemicals, and we conducted a series of computational analyses to evaluate its performance. Feature vectors extracted from the original high-dimensional space using two autoencoders equipped with both input and output layers in the model are used to build a mapping function from the feature space of mass spectra to the feature space of sensory data. The results of predictions obtained by the proposed new method have notable accuracy (R≅0.76) in comparison with a conventional method (R≅0.61). PMID:27326765

  9. Odor compound detection in male euglossine bees.

    PubMed

    Schiestl, F P; Roubik, D W

    2003-01-01

    Male euglossine bees collect fragrances from various sources, which they store and use for as yet unknown purposes. They are attracted, often specifically, to single odor compounds and blends thereof. We used gas chromatography with electroantennographic detection (GC-EAD) and electroantennography (EAG) to investigate the response to 8 odor compounds by males of two euglossine species, Euglossa cybelia Moure and Eulaema polychroma (Mocsàry). In E. cybelia, we recorded EAD reactions in response to 1,8-cineole, methyl benzoate, benzyl actetate, methyl salicylate, eugenol, and methyl cinnamate. E. polychroma responded to the same compounds in EAG experiments, while (1s)(-)alpha-pinene and beta-pinene failed to trigger EAD or EAG responses in the bees. Blends of two compounds triggered larger responses than single compounds in EAG experiments with E. polychroma, however, when alpha-pinene was added, reactions decreased. In the light of existing data on the bees' behavior towards these odor compounds, our work indicates that both peripheral and central nervous processes influence the attraction of euglossine bees to odors. PMID:12647866

  10. Source chemical characterization of swine odor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Odors from swine production have been linked to a host of issues affecting quality of life, property values and potentially human health. Typical compounds and classes of compounds include: sulfides, thiols, acids, phenols, indoles, ammonia and amines. The wide range of compounds assoicated with swi...

  11. Odor Impression Prediction from Mass Spectra.

    PubMed

    Nozaki, Yuji; Nakamoto, Takamichi

    2016-01-01

    The sense of smell arises from the perception of odors from chemicals. However, the relationship between the impression of odor and the numerous physicochemical parameters has yet to be understood owing to its complexity. As such, there is no established general method for predicting the impression of odor of a chemical only from its physicochemical properties. In this study, we designed a novel predictive model based on an artificial neural network with a deep structure for predicting odor impression utilizing the mass spectra of chemicals, and we conducted a series of computational analyses to evaluate its performance. Feature vectors extracted from the original high-dimensional space using two autoencoders equipped with both input and output layers in the model are used to build a mapping function from the feature space of mass spectra to the feature space of sensory data. The results of predictions obtained by the proposed new method have notable accuracy (R≅0.76) in comparison with a conventional method (R≅0.61). PMID:27326765

  12. EMISSIONS OF ODOROUS ALDEHYDES FROM ALKYD PAINT

    EPA Science Inventory

    Aldehyde emissions are widely held responsible for the acrid after-odor of drying alkyd-based paint films. The aldehyde emissions from three different alkyd paints were measured in small environmental chambers. It was found that, for each alkyd paint applied, more than 2 mg of ...

  13. On the dimensionality of odor space

    PubMed Central

    Meister, Markus

    2015-01-01

    There is great interest in understanding human olfactory experience from a principled and quantitative standpoint. The comparison is often made to color vision, where a solid framework with a three-dimensional perceptual space enabled a rigorous search for the underlying neural pathways, and the technological development of lifelike color display devices. A recent, highly publicized report claims that humans can discriminate at least 1 trillion odors, which exceeds by many orders of magnitude the known capabilities of color discrimination. This claim is wrong. I show that the failure lies in the mathematical method used to infer the size of odor space from a limited experimental sample. Further analysis focuses on establishing how many dimensions the perceptual odor space has. I explore the dimensionality of physical, neural, and perceptual spaces, drawing on results from bacteria to humans, and propose some experimental approaches to better estimate the number of discriminable odors. DOI: http://dx.doi.org/10.7554/eLife.07865.001 PMID:26151672

  14. The Effects of Odor Quality and Temporal Asynchrony on Modulation of Taste Intensity by Retronasal Odor.

    PubMed

    Isogai, Tomoyuki; Wise, Paul M

    2016-09-01

    The experiments had 2 main goals: 1) to add to the sparse literature on how retronasal aromas interact with bitter tastes, and 2) to determine whether modulation of taste intensity by aroma depends on temporal contiguity, as one might expect if flavor interactions depend on cross-modal binding (similar to object perception in other modalities). An olfactometer-gustometer allowed independent oral presentation of odorized air and liquid samples. First, using simultaneous presentation of odors and tastes (Experiments 1a-d) we found that a "sweet-smelling" aroma enhanced the rated sweetness of sucrose and decreased the rated bitterness of sucrose octaacetate (SOA), and that a "bitter-smelling" aroma enhanced the bitterness of SOA and decreased the sweetness of sucrose. Thus, with respect to effects on taste intensity, sweet and bitter aromas mimicked mixture-interactions between sweet and bitter tastes under current conditions. Next (Experiment 2), both odors were again paired with both tastes, with a parametric manipulation of odor onset. Odor presentation ranged from before taste delivery to after taste delivery. Enhancement of taste intensity was greatest with simultaneous onset, and greatly attenuated with offsets of 1s. These results are consistent with the idea that enhancement of taste by retronasal aroma depends on a temporal binding window like many other cross-modal interactions. The effects of temporal offsets on suppression of taste were inconclusive. These findings are discussed within the context of past work on odor-taste interactions. PMID:27143280

  15. Odor identification: perceptual and semantic dimensions.

    PubMed

    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

  16. Retronasal odor representations in the dorsal olfactory bulb of rats

    PubMed Central

    Gautam, Shree Hari; Verhagen, Justus V.

    2012-01-01

    Animals perceive their olfactory environment not only from odors originating in the external world (orthonasal route) but also from odors released in the oral cavity while eating food (retronasal route). Retronasal olfaction is crucial for the perception of food flavor in humans. However, little is known about the retronasal stimulus coding in the brain. The most basic question is if and how route affects the odor representations at the level of the olfactory bulb (OB), where odor quality codes originate. We used optical calcium imaging of presynaptic dorsal OB responses to odorants in anesthetized rats to ask whether the rat OB could be activated retronasally, and how these responses compare to orthonasal responses under similar conditions. We further investigated the effects of specific odorant properties on orthoversus retronasal response patterns. We found that at a physiologically relevant flow rate retronasal odorants can effectively reach the olfactory receptor neurons, eliciting glomerular response patterns that grossly overlap with those of orthonasal responses, but differ from the orthonasal patterns in the response amplitude and temporal dynamics. Interestingly, such differences correlated well with specific odorant properties. Less volatile odorants yielded relatively smaller responses retronasally, but volatility did not affect relative temporal profiles. More polar odorants responded with relatively longer onset latency and time to peak retronasally, but polarity did not affect relative response magnitudes. These data provide insight into the early stages of retronasal stimulus coding and establish relationships between ortho- and retronasal odor representations in the rat OB. PMID:22674270

  17. The influence of odorants on respiratory patterns in sleep.

    PubMed

    Arzi, Anat; Sela, Lee; Green, Amit; Givaty, Gili; Dagan, Yaron; Sobel, Noam

    2010-01-01

    To assess the feasibility of using odors as a potential mechanism for treating sleep apnea, we set out to test the hypothesis that odorants delivered during sleep would modify respiratory patterns without inducing arousal or wake in healthy sleepers. We used 2 mildly trigeminal odorants: the pleasant lavender and unpleasant vetiver oil and 2 pure olfactory odorants: the pleasant vanillin and unpleasant ammonium sulfide. During sleep, an olfactometer delivered a transient odorant every 9, 12, or 15 min (randomized), providing 21-37 odorant presentations per night. Each of 36 participants was studied for 1 night and with 1 of the 4 different odorants tested. In addition to standard overnight polysomnography, we employed highly accurate measurements of nasal and oral respiration. Odorants did not increase the frequency of arousals or wake but did influence respiration. Specifically, all 4 odorants transiently decreased inhalation and increased exhalation for up to 6 breaths following odor onset. This effect persisted regardless of odorant valence or stage of sleep. These results suggest that the olfactory system may provide a path to manipulate respiration in sleep. PMID:19917590

  18. Does odor and taste identification change during hyperemesis gravidarum?

    PubMed

    Yasar, Mehmet; Sagit, Mustafa; Zeki Uludag, Semih; Ozcan, Ibrahim

    2016-02-01

    Aim To investigate a difference in odor and taste identification among pregnant women with hyperemesis gravidarum, those with healthy pregnancy and non-pregnant women. Methods This prospective, controlled study included 33 pregnant women with hyperemesis gravidarum, 33 healthy pregnant and 26 non-pregnant women. For all participants, rhinological examinations were performed. Odor and taste identification were performed by holding Sniffin Sticks test battery (Burghart, Wedel, Germany) in all participants. Results There was a statistically significant difference in results of odor identification tests among the groups (p=0.031). Rose odor was selected as the most pleasant odor by the hyperemesis gravidarum group, 32 (96.9%). Orange odor was selected as the most pleasant odor by the healthy pregnant women, 33 (100%) whereas the banana odor was selected as the most pleasant odor by the healthy non-pregnant women, 10 (38.4%). In taste identification tests, there was a significant difference in total taste scores among the groups (p=0.003). Conclusion It is obvious that there is a need to evaluate odor thresholds and other parameters by detailed studies on odor perception in the context of hyperemesis gravidarum. PMID:26827707

  19. A broadly tuned mouse odorant receptor that detects nitrotoluenes

    PubMed Central

    Li, Jingyi; Haddad, Rafi; Chen, Sisi; Santos, Vanessa; Luetje, Charles W.

    2012-01-01

    Mammals employ large numbers of odorant receptors to sample and identify volatile chemicals in the environment. These receptors are thought to vary not only in specificity for particular odorants, but also in breadth of tuning. That is, some odorant receptors are narrowly focused on a few closely related structures, while other odorant receptors may be “broadly tuned”, responding to a wide variety of odorant structures. Here we have performed a detailed examination the mouse odorant receptor MOR256-17, demonstrating that this receptor is broadly tuned. This receptor responds to odorant structures that span a significant portion of a multi-dimensional odor space. However, we found that broad tuning was not a defining characteristic of other members the MOR256 subfamily. Two additional members of this odorant receptor subfamily (MOR256-8 and MOR256-22) were more narrowly focused on small sets of odorant structures. Interestingly, the receptive range of MOR256-17 encompassed a variety of nitrotoluenes, including various TNT synthesis intermediates, degradation products and TNT itself, suggesting the potential utility of odorant receptors in the development of sensing technologies for the detection of explosives and other forms of contraband. PMID:22443178

  20. A Central Neural Pathway Controlling Odor Tracking in Drosophila

    PubMed Central

    Slater, Gemma; Levy, Peter; Chan, K.L. Andrew

    2015-01-01

    Chemotaxis is important for the survival of most animals. How the brain translates sensory input into motor output beyond higher olfactory processing centers is largely unknown. We describe a group of excitatory neurons, termed Odd neurons, which are important for Drosophila larval chemotaxis. Odd neurons receive synaptic input from projection neurons in the calyx of the mushroom body and project axons to the central brain. Functional imaging shows that some of the Odd neurons respond to odor. Larvae in which Odd neurons are silenced are less efficient at odor tracking than controls and sample the odor space more frequently. Larvae in which the excitability of Odd neurons is increased are better at odor intensity discrimination and odor tracking. Thus, the Odd neurons represent a distinct pathway that regulates the sensitivity of the olfactory system to odor concentrations, demonstrating that efficient chemotaxis depends on processing of odor strength downstream of higher olfactory centers. PMID:25653345

  1. Semantic Knowledge Influences Prewired Hedonic Responses to Odors

    PubMed Central

    Poncelet, Johan; Rinck, Fanny; Ziessel, Anne; Joussain, Pauline; Thévenet, Marc; Rouby, Catherine; Bensafi, Moustafa

    2010-01-01

    Background Odor hedonic perception relies on decoding the physicochemical properties of odorant molecules and can be influenced in humans by semantic knowledge. The effect of semantic knowledge on such prewired hedonic processing over the life span has remained unclear. Methodology/Principal Findings The present study measured hedonic response to odors in different age groups (children, teenagers, young adults, and seniors) and found that children and seniors, two age groups characterized by either low level of (children) or weak access to (seniors) odor semantic knowledge, processed odor hedonics more on the basis of their physicochemical properties. In contrast, in teenagers and young adults, who show better levels of semantic odor representation, the role of physicochemical properties was less marked. Conclusions/Significance These findings demonstrate for the first time that the biological determinants that make an odor pleasant or unpleasant are more powerful at either end of the life span. PMID:21079734

  2. Temporal coding of odor mixtures in an olfactory receptor neuron

    PubMed Central

    Su, Chih-Ying; Martelli, Carlotta; Emonet, Thierry; Carlson, John R.

    2011-01-01

    Most natural odors are mixtures and often elicit percepts distinct from those elicited by their constituents. This emergence of a unique odor quality has long been attributed to central processing. Here we show that sophisticated integration of olfactory information begins in olfactory receptor neurons (ORNs) in Drosophila. Odor mixtures are encoded in the temporal dynamics as well as in the magnitudes of ORN responses. ORNs can respond to an inhibitory odorant with different durations depending on the level of background excitation. ORNs respond to mixtures with distinctive temporal dynamics that reflect the physicochemical properties of the constituent odorants. The insect repellent DEET (N,N-diethyl-m-toluamide), which attenuates odor responses of multiple ORNs, differs from an ORN-specific inhibitor in its effects on temporal dynamics. Our analysis reveals a means by which integration of information from odor mixtures begins in ORNs and provides insight into the contribution of inhibitory stimuli to sensory coding. PMID:21383179

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

    PubMed Central

    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

  4. Preharvest measures for postharvest improvement in marketable fresh citrus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus canker caused by the bacterium Xanthomonas citri supsp. citri, (Xcc), was once the scourge of the Florida citrus industry from the early 1900’s on and off until the early 1990’s. It has been replaced, for the most part, by citrus greening but still continues to be a problem for Florida fresh ...

  5. Studies on the aroma of five fresh tomato cultivars and the precursors of cis- and trans-4,5-epoxy-(E)-2-decenals and methional.

    PubMed

    Mayer, Florian; Takeoka, Gary R; Buttery, Ron G; Whitehand, Linda C; Naim, Michael; Rabinowitch, Haim D

    2008-05-28

    Three tasty (BR-139, FA-624, and FA-612) and two less tasty (R-144 and R-175) fresh greenhouse tomato cultivars, which significantly differ in their flavor profiles, were screened for potent odorants using aroma extract dilution analysis (AEDA). On the basis of AEDA results, 19 volatiles were selected for quantification in those 5 cultivars using gas chromatography-mass spectrometry (GC-MS). Compounds such as 1-penten-3-one, ( E, E)- and ( E, Z)-2,4-decadienal, and 4-hydroxy-2,5-dimethyl-3(2 H)-furanone (Furaneol) had higher odor units in the more preferred cultivars, whereas methional, phenylacetaldehyde, 2-phenylethanol, or 2-isobutylthiazole had higher odor units in the less preferred cultivars. Simulation of the odor of the selected tomato cultivars by preparation of aroma models and comparison with the corresponding real samples confirmed that all important fresh tomato odorants were identified, that their concentrations were determined correctly in all five cultivars, and that differences in concentration, especially of the compounds mentioned above, make it possible to distinguish between them and are responsible for the differential preference. To help elucidate formation pathways of key odorants, labeled precursors were added to tomatoes. Biogenesis of cis- and trans-4,5-epoxy-( E)-2-decenals from linoleic acid and methional from methionine was confirmed. PMID:18459793

  6. From cats and blackcurrants: structure and dynamics of the sulfur-containing cassis odorant cat ketone.

    PubMed

    Mouhib, Halima; Stahl, Wolfgang

    2014-10-01

    Sulfur-containing odorants and flavors play an important role in flavor and food industry, especially when meaty, garlic, onion, and vegetable scents are needed. Still, many S-containing flavors also possess fruity scents and may be used in compositions of perfumes that require a fresh and fruity odor perception. They are naturally abundant in various fruits, essential oils, and food. Most of these compounds possess strong scents, and their scent composition is highly dependent on the concentration applied. At higher concentrations, they usually feature repellent off-odors, while their sweet and fruity nature is only experienced at very low concentrations. This represents a challenge for their application in perfumery, as well as in food industry. From a molecular point of view, the endless structural and scent variety of these compounds makes them fascinating, especially as their O-analogs are usually free of any malodors. Here, we report on the investigation of the gas-phase structure and dynamics of the S-containing blackcurrant odorant cat ketone (4-methyl-4-sulfanylpentan-2-one). The work was performed by combining quantum-chemical calculations and molecular-beam Fourier-transform microwave spectroscopy as complementary tools. Using this technique, we are able to determine the structures of sizeable molecules where energy differences are small and conformational distinction is not always possible by quantum-chemical calculations alone. The presented results can be used for further structure-activity correlation studies, as well as for benchmarks to improve theoretical models, especially, as there is still significant interest in characterizing the various conformers of organic molecules in terms of relative energies, structures, and dipole moments. PMID:25329784

  7. Aroma profile and volatiles odor activity along gold cultivar pineapple flesh.

    PubMed

    Montero-Calderón, Marta; Rojas-Graü, María Alejandra; Martín-Belloso, Olga

    2010-01-01

    Physicochemical attributes, aroma profile, and odor contribution of pineapple flesh were studied for the top, middle, and bottom cross-sections cut along the central axis of Gold cultivar pineapple. Relationships between volatile and nonvolatile compounds were also studied. Aroma profile constituents were determined by headspace solid-phase microextraction at 30 °C, followed by gas chromatography/mass spectrometry analysis. A total of 20 volatile compounds were identified and quantified. Among them, esters were the major components which accounted for 90% of total extracted aroma. Methyl butanoate, methyl 2-methyl butanoate, and methyl hexanoate were the 3 most abundant components representing 74% of total volatiles in pineapple samples. Most odor active contributors were methyl and ethyl 2-methyl butanoate and 2,5-dimethyl 4-methoxy 3(2H)-furanone (mesifuran). Aroma profile components did not vary along the fruit, but volatile compounds content significantly varied (P < 0.05) along the fruit, from 7560 to 10910 μg/kg, from the top to the bottom cross-sections of the fruit, respectively. In addition, most odor-active volatiles concentration increased from the top to the bottom 3rd of the fruit, concurrently with soluble solids content (SSC) and titratable acidity (TA) differences attributed to fruitlets distinct degree of ripening. Large changes in SSC/TA ratio and volatiles content throughout the fruit found through this study are likely to provoke important differences among individual fresh-cut pineapple trays, compromising consumer perception and acceptance of the product. Such finding highlighted the need to include volatiles content and SSC/TA ratio and their variability along the fruit as selection criteria for pineapples to be processed and quality assessment of the fresh-cut fruit. PMID:21535624

  8. Human Odorant Reception in the Common Bed Bug, Cimex lectularius.

    PubMed

    Liu, Feng; Liu, Nannan

    2015-01-01

    The common bed bug Cimex lectularius is a temporary ectoparasite on humans and currently resurgent in many developed countries. The ability of bed bugs to detect human odorants in the environment is critical for their host-seeking behavior. This study deciphered the chemical basis of host detection by investigating the neuronal response of olfactory sensilla to 104 human odorants using single sensillum recording and characterized the electro-physiological responses of bed bug odorant receptors to human odorants with the Xenopus expression system. The results showed that the D type of olfactory sensilla play a predominant role in detecting the human odorants tested. Different human odorants elicited different neuronal responses with different firing frequencies and temporal dynamics. Particularly, aldehydes and alcohols are the most effective stimuli in triggering strong response while none of the carboxylic acids showed a strong stimulation. Functional characterization of two bed bug odorant receptors and co-receptors in response to human odorants revealed their specific responses to the aldehyde human odorants. Taken together, the findings of this study not only provide exciting new insights into the human odorant detection of bed bugs, but also offer valuable information for developing new reagents (attractants or repellents) for the bed bug control. PMID:26522967

  9. Classification of odorants across layers in locust olfactory pathway.

    PubMed

    Sanda, Pavel; Kee, Tiffany; Gupta, Nitin; Stopfer, Mark; Bazhenov, Maxim

    2016-05-01

    Olfactory processing takes place across multiple layers of neurons from the transduction of odorants in the periphery, to odor quality processing, learning, and decision making in higher olfactory structures. In insects, projection neurons (PNs) in the antennal lobe send odor information to the Kenyon cells (KCs) of the mushroom bodies and lateral horn neurons (LHNs). To examine the odor information content in different structures of the insect brain, antennal lobe, mushroom bodies and lateral horn, we designed a model of the olfactory network based on electrophysiological recordings made in vivo in the locust. We found that populations of all types (PNs, LHNs, and KCs) had lower odor classification error rates than individual cells of any given type. This improvement was quantitatively different from that observed using uniform populations of identical neurons compared with spatially structured population of neurons tuned to different odor features. This result, therefore, reflects an emergent network property. Odor classification improved with increasing stimulus duration: for similar odorants, KC and LHN ensembles reached optimal discrimination within the first 300-500 ms of the odor response. Performance improvement with time was much greater for a population of cells than for individual neurons. We conclude that, for PNs, LHNs, and KCs, ensemble responses are always much more informative than single-cell responses, despite the accumulation of noise along with odor information. PMID:26864765

  10. Human Odorant Reception in the Common Bed Bug, Cimex lectularius

    PubMed Central

    Liu, Feng; Liu, Nannan

    2015-01-01

    The common bed bug Cimex lectularius is a temporary ectoparasite on humans and currently resurgent in many developed countries. The ability of bed bugs to detect human odorants in the environment is critical for their host-seeking behavior. This study deciphered the chemical basis of host detection by investigating the neuronal response of olfactory sensilla to 104 human odorants using single sensillum recording and characterized the electro-physiological responses of bed bug odorant receptors to human odorants with the Xenopus expression system. The results showed that the D type of olfactory sensilla play a predominant role in detecting the human odorants tested. Different human odorants elicited different neuronal responses with different firing frequencies and temporal dynamics. Particularly, aldehydes and alcohols are the most effective stimuli in triggering strong response while none of the carboxylic acids showed a strong stimulation. Functional characterization of two bed bug odorant receptors and co-receptors in response to human odorants revealed their specific responses to the aldehyde human odorants. Taken together, the findings of this study not only provide exciting new insights into the human odorant detection of bed bugs, but also offer valuable information for developing new reagents (attractants or repellents) for the bed bug control. PMID:26522967

  11. Visually induced motion sickness can be alleviated by pleasant odors.

    PubMed

    Keshavarz, Behrang; Stelzmann, Daniela; Paillard, Aurore; Hecht, Heiko

    2015-05-01

    Visually induced motion sickness (VIMS) is a common side effect in virtual environments and simulators. Several countermeasures against VIMS exist, but a reliable method to prevent or ease VIMS is unfortunately still missing. In the present study, we tested whether olfactory cues can alleviate VIMS. Sixty-two participants were exposed to a 15-min-long video showing a first-person-view bicycle ride that had successfully induced VIMS in previous studies. Participants were randomly assigned to one of three groups; the first group was exposed to a pleasant odor (rose) while watching the video, the second group was exposed to an unpleasant odor (leather), and the third group was not exposed to any odor. VIMS was measured using a verbal rating scale (0-20) and the Simulator Sickness Questionnaire. Results showed that only half of the participants who were exposed to the odor did notice it (n = 21), whereas the other half failed to detect the odor. However, among those participants who did notice the odor, the rose scent significantly reduced the severity of VIMS compared to the group that did not notice the odor. A moderate positive correlation between odor sensitivity and VIMS showed that participants with higher odor sensitivity also reported stronger VIMS. Our results demonstrate that olfaction can modulate VIMS and that a pleasant odor can potentially reduce VIMS. The relationship between olfactory perception, olfactory sensibility, and VIMS is discussed. PMID:25633319

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

    PubMed

    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. PMID:26567342

  13. Air Pollution and Odor in Communities Near Industrial Swine Operations

    PubMed Central

    Wing, Steve; Horton, Rachel Avery; Marshall, Stephen W.; Thu, Kendall; Tajik, Mansoureh; Schinasi, Leah; Schiffman, Susan S.

    2008-01-01

    Background Odors can affect health and quality of life. Industrialized animal agriculture creates odorant compounds that are components of a mixture of agents that could trigger symptoms reported by neighbors of livestock operations. Objective We quantified swine odor episodes reported by neighbors and the relationships of these episodes with environmental measurements. Methods Between September 2003 and September 2005, 101 nonsmoking volunteers living within 1.5 mi of industrial swine operations in 16 neighborhoods in eastern North Carolina completed twice-daily odor diaries for approximately 2 weeks. Meteorological conditions, hydrogen sulfide, and particulate matter ≤ 10 μm in aerodynamic diameter (PM10) were monitored in each neighborhood. We used mixed models to partition odor variance within and between people and between neighborhoods, and to quantify relationships between environmental factors and odor. Results Participants reported 1,655 episodes of swine odor. In nine neighborhoods, odor was reported on more than half of study-days. Odor ratings were related to temperature, PM10, and semivolatile PM10 in standard but not mixed models. In mixed models, odor increased 0.15 ± 0.05 units (mean ± SE) for a 1-ppb increase in H2S, and 0.45 ± 0.14 units for a 10-μg/m3 increase in PM10 at wind speeds > 6.75 miles per hour. The odds of reporting a change in daily activities due to odor increased 62% for each unit increase in average odor during the prior 12 hr (t-value = 7.17). Conclusions This study indicates that malodor from swine operations is commonly present in these communities and that the odors reported by neighbors are related to objective environmental measurements and interruption of activities of daily life. PMID:18941579

  14. Body Odor Based Personality Judgments: The Effect of Fragranced Cosmetics.

    PubMed

    Sorokowska, Agnieszka; Sorokowski, Piotr; Havlíček, Jan

    2016-01-01

    People can accurately assess various personality traits of others based on body odor (BO) 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 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; r s = 0.20) than in the cosmetics use condition (BO+cosmetics condition; r s = 0.15). Ratings of dominance significantly predicted self-assessed dominance in both conditions (r s = 0.34 for natural BO and r s = 0.21 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. PMID:27148138

  15. Body Odor Based Personality Judgments: The Effect of Fragranced Cosmetics

    PubMed Central

    Sorokowska, Agnieszka; Sorokowski, Piotr; Havlíček, Jan

    2016-01-01

    People can accurately assess various personality traits of others based on body odor (BO) 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 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 = 0.20) than in the cosmetics use condition (BO+cosmetics condition; rs = 0.15). Ratings of dominance significantly predicted self-assessed dominance in both conditions (rs = 0.34 for natural BO and rs = 0.21 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. PMID:27148138

  16. Differences in key odorants of handmade juice of yellow-flesh peaches (Prunus persica L.) induced by the workup procedure.

    PubMed

    Derail, C; Hofmann, T; Schieberle, P

    1999-11-01

    Application of aroma extract dilution analysis (AEDA) on a flavor extract isolated from a freshly prepared, enzyme-inactivated peach juice using solvent extraction and high-vacuum distillation (extract I) revealed 24 odor-active regions in the gas chromatogram. Flavor dilution (FD) factors ranged from 4 to 512. The highest FD factors were determined for beta-damascenone (cooked-apple-like) and gamma-decalactone (peach-like). Cooking of peaches for 2 h in an apparatus equipped for simultaneous steam distillation/extraction (extract II) yielded an overall more intense aroma extract (extract II). By AEDA, 30 odorants were detected in the FD-factor region of 4-16384 and were subsequently identified. The results revealed that in extract II, besides the two above-mentioned aroma compounds, both had FD factors of 16 384; delta-decalactone, gamma-dodecalactone additionally, and 6-dodeceno-gamma-lactone contributed with very high FD factors (FD 8192) to the overall aroma. In general, the thermal treatment led to the formation of 15 new odorants which were not detected in I. Furthermore, the lactones and beta-damascenone were significantly increased in II, thereby indicating their generation from precursors in the fresh juice. PMID:10552883

  17. Development of a livestock odor dispersion model: part II. Evaluation and validation.

    PubMed

    Yu, Zimu; Guo, Huiqing; Laguë, Claude

    2011-03-01

    A livestock odor dispersion model (LODM) was developed to predict odor concentration and odor frequency using routine hourly meteorological data input. The odor concentrations predicted by the LODM were compared with the results obtained from other commercial models (Industrial Source Complex Short-Term model, version 3, CALPUFF) to evaluate its appropriateness. Two sets of field odor plume measurement data were used to validate the model. The model-predicted mean odor concentrations and odor frequencies were compared with those measured. Results show that this model has good performance for predicting odor concentrations and odor frequencies. PMID:21416754

  18. Imaging of musty-odor producing filamentous cyanobacteria by various microscopies

    NASA Astrophysics Data System (ADS)

    Takemoto, K.; Yoshimura, M.; Yamamoto, A.; Ichise, S.; Namba, H.; Kihara, H.

    2016-01-01

    A method for the determination of filamentous cyanobacteria producing musty-odor substances quickly and accurately by soft X-ray microscopy (XM) was developed and applied to Phormidum tenue sp. (Pseudanabaena sp.) green strain (PTG). To improve the identification accuracy of PTG, PTG was observed by soft XM using two wavelengths above and below the K-edge of oxygen. Two types of granules were confirmed. Since a granule of which oxygen is a major constituent element is identified as polyphosphate granule, polyphosphate granule and carboxysome are identified, respectively.

  19. Green manures and plant disease management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of green manures, which involves the incorporation of fresh plant material, has traditionally been primarily for the purpose of soil enrichment through the addition of plant organic matter and nutrients. However, green manures produce many changes in soil physical, chemical, and biological p...

  20. Odor and chemical emissions from dairy and swine facilities: Part 1 - project overview and collection methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Livestock facilities have received numerous criticisms due to their emissions of odorous air and chemicals. Hence, there is a significant need for odor emission factors and identification of principle odorous chemicals. Odor emission factors are used as inputs to odor setback models, while chemica...

  1. Chemical Composition and Characteristic Odor Compounds in Essential Oil from Alismatis Rhizoma (Tubers of Alisma orientale).

    PubMed

    Miyazawa, Mitsuo; Yoshinaga, Seiji; Kashima, Yusei; Nakahashi, Hiroshi; Hara, Nobuyuki; Nakagawa, Hiroki; Usami, Atsushi

    2016-01-01

    Chemical composition and potent odorants that contribute to the characteristic odor of essential oil from Alismatis Rhizoma (tubers of Alisma orientale) were investigated by gas chromatography-mass spectrometry (GC-MS), GC-olfactometry (GC-O), aroma extract dilution analysis (AEDA) and relative flavor activity (RFA) methods. Fifty components, representing 94.5% of the total oil, were identified. In this study, we newly identified thirty-nine compounds in the oil from tubers of A. orientale. The major constituents of the essential oil were khusinol (36.2%), δ-elemene (12.4%), germacron (4.1%), alismol (3.8%), β-elemene (3.1%), and α-bisabolol (1.9%). Through sensory analysis, sixteen aroma-active compounds were detected and the key contributing aroma-active compounds were δ-elemene (woody, flavor dilution (FD)-factor = 4, RFA = 0.3) β-elemene (spicy, FD = 5, RFA = 0.7), spathulenol (green, FD = 5, RFA = 1.0), γ-eudesmol (woody, FD = 6, RFA = 1.5), and γ-cadinol (woody, FD = 5, RFA = 1.0). These compounds are thought to contribute to the odor from tubers of A. orientale. These results imply that the essential oil from the tubers of A. orientale deserve further investigations in the phytochemical and medicinal fields. PMID:26666273

  2. Nuisance Odors: Is there a Concern - 12340

    SciTech Connect

    Brounstein, Robert A.

    2012-07-01

    Nuisance odors are generally thought of as just being annoying or unpleasant and not causing any physiological harm to our internal organs or other biologic systems. Yet during an excavation of buried animal remains, field workers experienced a multitude of symptoms that are associated with exposures to toxic materials. An examination of the decomposition process revealed that there is a potential off-gassing of a number of common, yet harmful chemicals including ammonia, mercaptans, hydrogen sulfide, butyric acid and phenol. In addition, other compounds, that have limited information such as established health data and occupational exposure limits, were also potential contaminants-of-concern. While a variety of monitoring and sampling techniques were used to assess worker exposures, all results indicated non-detectable airborne concentrations. Nevertheless, workers were experiencing such symptoms as nausea and headaches. As such, protective measures were necessary for field personnel to continue work while having confidence that the project was instituting sincere steps to ensure their health and safety. Researching the possible reasons for the causes of workers exhibiting adverse health effects from nuisance odors revealed that such exposures initiate electrochemical pathways, starting from the olfactory bulb to the brain, followed by a transfer of information to such biologic systems as the hypothalamus and pituitary gland. These systems, in turn, secrete hormones that cause a number of involuntary reactions; many of which are observed as typical adverse health effects, when in fact, they are merely reactions caused by the brain's memory; most likely created from previous experiences to unpleasant odors. The concern then focuses of how the Occupational Safety and Health community shall respond to such workplace exposures. Future work in this area may need to focus on the viability of current occupational exposure limits and the possibility of revising these

  3. Odor and pheromone sensing via chemoreceptors.

    PubMed

    Ma, Minghong

    2012-01-01

    Evolutionally, chemosensation is an ancient but yet enigmatic sense. All organisms ranging from the simplest unicellular form to the most advanced multicellular creature possess the capability to detect chemicals in the surroundings. Conversely, all living things emit some forms of smells, either as communicating signals or as by-products of metabolism. Many species (from worms, insects to mammals) rely on the olfactory systems which express a large number of chemoreceptors to locate food and mates and to avoid danger. Most chemoreceptors expressed in olfactory organs are G-protein coupled receptors (GPCRs) and can be classified into two major categories: odorant receptors (ORs) and pheromone receptors, which principally detect general odors and pheromones, respectively. In vertebrates, these two types of receptors are often expressed in two distinct apparatuses: The main olfactory epithelium (MOE) and the vomeronasal organ (VNO), respectively. Each olfactory sensory neuron (OSN) in the MOE typically expresses one type of OR from a large repertoire. General odors activate ORs and their host OSNs (ranging from narrowly- to broadly-tuned) in a combinatorial manner and the information is sent to the brain via the main olfactory system leading to perception of smells. In contrast, pheromones stimulate relatively narrowly-tuned receptors and their host VNO neurons and the information is sent to the brain via the accessory olfactory system leading to behavioral and endocrinological changes. Recent studies indicate that the functional separation between these two systems is blurred in some cases and there are more subsystems serving chemosensory roles. This chapter focuses on the molecular and cellular mechanisms underlying odor and pheromone sensing in rodents, the best characterized vertebrate models. PMID:22399397

  4. Odor and odorous chemical emissions from animal buildings: Part 5 - Correlations between odor intensities and chemical concentrations (GC-MS/O)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Simultaneous chemical and sensory analysis based on gas chromatography-mass spectrometry-olfactometry (GC-MS-O) of air samples from livestock operations is a very useful approach for quantification of target odorous gases and also for ranking of odorous compounds. This information can help link spec...

  5. Odor Identification and Mortality in Old Age

    PubMed Central

    Yu, Lei; Bennett, David A.

    2011-01-01

    The association of olfactory dysfunction with mortality was examined in 1162 older persons without dementia or Parkinson's disease. They completed a standard 12-item test of odor identification and then were followed for a mean of 4.2 years (standard deviation [SD] = 2.6, range: 0–9) during which 321 individuals died (27.6%). The relation of olfactory score to risk of death was assessed in a series of proportional hazards models adjusted for age, sex, education, and other covariates. Olfactory scores ranged from 0 to 12 correct (mean = 9.0, SD = 2.2). In an initial analysis, risk of death decreased by about 6% for each additional odor correctly identified (hazard ratio = 0.94; 95% confidence interval: 0.90, 0.98). Thus, mortality risk was about 36% higher with a low score (6, 10th percentile) compared with a high score (11, 90th percentile). The association persisted in subsequent analyses that controlled for naming ability, disability, cerebrovascular disease, characteristic patterns of leisure activity, depressive symptoms, and apolipoprotein E genotype. The results indicate that difficulty identifying familiar odors in old age is associated with increased risk of death. PMID:20923931

  6. Odor analysis of decomposing buried human remains

    SciTech Connect

    Vass, Arpad Alexander; Smith, Rob R; Thompson, Cyril V; Burnett, Michael N; Dulgerian, Nishan; Eckenrode, Brian A

    2008-01-01

    This study, conducted at the University of Tennessee's Anthropological Research Facility (ARF), lists and ranks the primary chemical constituents which define the odor of decomposition of human remains as detected at the soil surface of shallow burial sites. Triple sorbent traps were used to collect air samples in the field and revealed eight major classes of chemicals which now contain 478 specific volatile compounds associated with burial decomposition. Samples were analyzed using gas chromatography-mass spectrometry (GC-MS) and were collected below and above the body, and at the soil surface of 1.5-3.5 ft. (0.46-1.07 m) deep burial sites of four individuals over a 4-year time span. New data were incorporated into the previously established Decompositional Odor Analysis (DOA) Database providing identification, chemical trends, and semi-quantitation of chemicals for evaluation. This research identifies the 'odor signatures' unique to the decomposition of buried human remains with projected ramifications on human remains detection canine training procedures and in the development of field portable analytical instruments which can be used to locate human remains in shallow burial sites.

  7. Effects of reproductive state on olfactory sensitivity suggest odor specificity.

    PubMed

    Lundström, Johan N; McClintock, Martha K; Olsson, Mats J

    2006-03-01

    Previous studies of reproductive state and olfactory sensitivity in women have not directly compared thresholds for social and environmental odors. Here, we used successive dilutions presented in a staircase protocol to determine olfactory thresholds for androstadienone, a social odor produced by men, and rose, an environmental odor signaling a source of micronutrients essential for successful implantation, prenatal development and maternal health. Fertile women were more sensitive to the social than the environmental odor, while women using oral contraceptives, a non-fertile hormonal state similar to early pregnancy, were more sensitive to the environmental odor. This preliminary study sets the stage for further work on the interaction between hormonal states and sensitivity to specific odors with reproductive significance. PMID:16084006

  8. Odorant Transport and Deposition in the Canine Nasal Airways

    NASA Astrophysics Data System (ADS)

    Lawson, Michael; Craven, Brent; Settles, Gary; Paterson, Eric

    2009-11-01

    The canine nose functions similar to a chromatograph that imposes odorant-specific deposition patterns upon the thin mucus layer covering the nasal cavity. Here we use an anatomically-correct computational fluid dynamics (CFD) model to study airflow and odorant transport from the external environment through the nasal airways to the olfactory receptor layer beneath the mucus. The results show that deposition patterns are primarily influenced by the intricate olfactory flowfield and the odorant solubility in the mucus layer. Highly-soluble odorants are quickly absorbed near the entrance to the olfactory region, and thus do not reach the periphery with significant concentrations. In contrast, insoluble odorants are deposited more evenly and may even exit the olfactory region without being completely absorbed. Predicted odorant deposition patterns correspond with the anatomical organization of olfactory receptors known to occur in keen-scented (macrosmatic) mammals, providing a mechanism that helps explain the excellent olfactory acuity of the dog.

  9. Neural Coding of Perceived Odor Intensity1,2,3

    PubMed Central

    Sirotin, Yevgeniy B.; Shusterman, Roman

    2015-01-01

    Abstract Stimulus intensity is a fundamental perceptual feature in all sensory systems. In olfaction, perceived odor intensity depends on at least two variables: odor concentration; and duration of the odor exposure or adaptation. To examine how neural activity at early stages of the olfactory system represents features relevant to intensity perception, we studied the responses of mitral/tufted cells (MTCs) while manipulating odor concentration and exposure duration. Temporal profiles of MTC responses to odors changed both as a function of concentration and with adaptation. However, despite the complexity of these responses, adaptation and concentration dependencies behaved similarly. These similarities were visualized by principal component analysis of average population responses and were quantified by discriminant analysis in a trial-by-trial manner. The qualitative functional dependencies of neuronal responses paralleled psychophysics results in humans. We suggest that temporal patterns of MTC responses in the olfactory bulb contribute to an internal perceptual variable: odor intensity. PMID:26665162

  10. AN ODORANT-BINDING PROTEIN INVOLVED IN PERCEPTION OF HOST PLANT ODORANTS IN LOCUST Locusta migratoria.

    PubMed

    Li, Jia; Zhang, Long; Wang, Xiaoqi

    2016-04-01

    Locusts, Locusta migratoria (Orthoptera: Acrididae), are extremely destructive agricultural pests, but very little is known of their molecular aspects of perception to host plant odorants including related odorant-binding proteins (OBPs), though several OBPs have been identified in locust. To elucidate the function of LmigOBP1, the first OBP identified from locust, RNA interference was employed in this study to silence LmigOBP1, which was achieved by injection of dsRNA targeting LmigOBP1 into the hemolymph of male nymphs. Compared with LmigOBP1 normal nymphs, LmigOBP1 knockdown nymphs significantly decreased food (maize leaf, Zea mays) consumption and electro-antennography responses to five maize leaf volatiles, ((Z)-3-hexenol, linalool, nonanal, decanal, and (Z)-3-hexenyl acetate). These suggest that LmigOBP1 is involved in perception of host plant odorants. PMID:26864243

  11. Good odorant practices ensure safer operations. [Natural gas odorant detection methods

    SciTech Connect

    Oudman, P. )

    1993-12-01

    Regulations in Canada and the US require that combustible gas used as a fuel be odorized at such a level that a concentration in air of one-fifth the lower explosive limit the gas can be readily detected and recognized by a person with a normal sense of smell. These regulations do not specify how the odorant level should be determined. However, since the requirement is related to smell, the level should be determined by an olfactory method. There are two odorant monitoring methods commonly used by gas companies, the olfactory (odorometer) and the instrumentation (gas chromatograph) methods. The instrument method provides only quantitative results, which somehow must be related to an olfactory response. This paper discusses these methods.

  12. Preserving Fresh Fruit

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Geo-Centers, Inc. has developed an Ethlyene Monitoring and Control System through an SBIR contract with Kennedy Space Center. As plants grow, they produce by products of ethylene and ammonia which are harmful to plant development. The system provides optimal exposure of fruit to ethylene since the proper balance in ethylene is necessary to prevent fruit loss. It can be used to monitor the de-greening process of citrus fruits, in particular.

  13. Recent developments in the chemistry of sandalwood odorants.

    PubMed

    Brocke, Constanze; Eh, Marcus; Finke, Anja

    2008-06-01

    Natural sandalwood oil, a unique and valuable ingredient in fine perfumery, has been the focus of scientific interest for many years. Due to its scarcity and its high price, the search for novel synthetic raw materials imitating the characteristic odor profile of sandalwood oil is as challenging as ever. In this context, the preparation of the novel sandalwood odorants 26, 33, and 39 will be discussed, including their sensory properties and structure-odor relationship. PMID:18618410

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

    PubMed Central

    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

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

    PubMed Central

    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. PMID:27138751

  16. Studies on the Aroma of Five Fresh Tomato Cultivars and the Precursors of the cis- and trans-4,5-Epoxy-(E)-2-Decenals and Methional

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three tasty (BR-139, FA-624 and FA-612) and two less tasty (R 144 and R 175) fresh greenhouse tomato cultivars, which significantly differ in their flavor profiles, were screened for potent odorants using aroma extract dilution analysis (AEDA). Based on AEDA results, 19 volatiles were selected for ...

  17. Full evaporation dynamic headspace and gas chromatography-mass spectrometry for uniform enrichment of odor compounds in aqueous samples.

    PubMed

    Ochiai, Nobuo; Sasamoto, Kikuo; Hoffmann, Andreas; Okanoya, Kazunori

    2012-06-01

    A method for analysis of a wide range of odor compounds in aqueous samples at sub-ng mL⁻¹ to μg mL⁻¹ levels was developed by full evaporation dynamic headspace (FEDHS) and gas chromatography-mass spectrometry (GC-MS). Compared to conventional DHS and headspace solid phase microextraction (HS-SPME), FEDHS provides more uniform enrichment over the entire polarity range for odor compounds in aqueous samples. FEDHS at 80°C using 3 L of purge gas allows complete vaporization of 100 μL of an aqueous sample, and trapping and drying it in an adsorbent packed tube, while providing high recoveries (85-103%) of the 18 model odor compounds (water solubility at 25°C: log0.54-5.65 mg L⁻¹, vapor pressure at 25°C: 0.011-3.2 mm Hg) and leaving most of the low volatile matrix behind. The FEDHS-GC-MS method showed good linearity (r²>0.9909) and high sensitivity (limit of detection: 0.21-5.2 ng mL⁻¹) for the model compounds even with the scan mode in the conventional MS. The feasibility and benefit of the method was demonstrated with analyses of key odor compounds including hydrophilic and less volatile characteristics in beverages (whiskey and green tea). In a single malt whiskey sample, phenolic compounds including vanillin could be determined in the range of 0.92-5.1 μg mL⁻¹ (RSD<7.4%, n=6). For a Japanese green tea sample, 48 compounds including 19 potent odorants were positively identified from only 100 μL of sample. Heat-induced artifact formation for potent odorants was also examined and the proposed method does not affect the additional formation of thermally generated compounds. Eighteen compounds including 12 potent odorants (e.g. coumarin, furaneol, indole, maltol, and pyrazine congeners) were determined in the range of 0.21-110 ng mL⁻¹ (RSD<10%, n=6). PMID:22542289

  18. Simulation of the Process of Odorizing a Natural Gas

    NASA Astrophysics Data System (ADS)

    Tukmakov, A. L.; Mubarakshin, B. R.; Tonkonog, V. G.

    2016-01-01

    A model of odorizing a natural gas is built on the basis of the system of motion of viscous, compressible, heatconducting, two-component medium with account for the odorant diffusion. Calculations of convective and diffusional mixing, in a channel, of a gaseous methane main flow interacting with its side jets containing an odorizing gas has been performed. The regimes of flow at different gas velocities in the main and side channels are considered, and the process of the equalization of the odorant concentration by convective and diffusional mechanisms are considered.

  19. A field study on downwind odor transport from swine facilities.

    PubMed

    Zhu, J; Li, X

    2000-03-01

    This paper presents field data to illustrate the characteristics of downwind odor dispersion. A total of eight swine facilities were studied in this project and power functions were found to be an appropriate description of the pattern of downwind odor transport for both swine buildings and manure storage lagoons and tanks. The coefficients of correlation for the power regressions ranged from 0.75-0.87. It was found that swine buildings have the potential of generating more odor than manure storage facilities such as lagoons and tanks and thus could be the major odor sources causing downwind odor nuisance. Therefore, to maintain the building clean should be highly recommended as swine producers' best management practice. For earthen basins, the odor strength was reduced by 80% at about 250-meter distance from the source. While for the swine building, a 50% of reduction in odor strength was observed at the same distance. The study did not show any advantages of using lagoons over concrete (or steel) manure tanks in terms of reducing downwind odor concentrations. Land application of manure did not cause persistent downwind odor problems. PMID:10736772

  20. Odorant-Binding Protein: Localization to Nasal Glands and Secretions

    NASA Astrophysics Data System (ADS)

    Pevsner, Jonathan; Sklar, Pamela B.; Snyder, Solomon H.

    1986-07-01

    An odorant-binding protein (OBP) was isolated from bovine olfactory and respiratory mucosa. We have produced polyclonal antisera to this protein and report its immunohistochemical localization to mucus-secreting glands of the olfactory and respiratory mucosa. Although OBP was originally isolated as a pyrazine binding protein, both rat and bovine OBP also bind the odorants [3H]methyldihydrojasmonate and 3,7-dimethyl-octan-1-ol as well as 2-isobutyl-3-[3H]methoxypyrazine. We detect substantial odorant-binding activity attributable to OBP in secreted rat nasal mucus and tears but not in saliva, suggesting a role for OBP in transporting or concentrating odorants.

  1. Odor annoyance of environmental chemicals: sensory and cognitive influences.

    PubMed

    van Thriel, Christoph; Kiesswetter, Ernst; Schäper, Michael; Juran, Stephanie A; Blaszkewicz, Meinolf; Kleinbeck, Stefan

    2008-01-01

    In low concentrations, environment pollutants like volatile organic compounds (VOCs) may be perceived via olfaction. Modulators of odor-mediated health effects include age, gender, or personality traits related to chemical sensitivity. Severe multi-organ symptoms in response to odors also characterize a syndrome referred to as idiopathic environmental intolerance (IEI). One prominent feature of IEI is self-reported odor hypersensitivity that is usually not accompanied by enhanced olfactory functioning. The impact of interindividual differences in olfactory functioning on chemosensory perceptions is sparsely investigated, and therefore this study addressed the influences of different types of modulators, including olfactory functioning. In a psychophysical scaling experiment, an age-stratified sample of 44 males and females was examined. After controlled application of nine concentrations of six chemicals by flow-olfactometry, the participants rated four olfactory and nine trigeminal perceptions. Weak effects were found for gender and age, as well as some modulating effects of self-reported chemical sensitivity and odor discrimination ability. For chemical sensitivity, the results were as expected: Subjects with higher sensitivity reported stronger perceptions. The individual odor threshold (n-butanol) exerted no influence on the subjects' ratings of olfactory and trigeminal perceptions. Surprisingly, above-average odor discrimination ability was associated with lower ratings of odor intensity and nausea. This particular aspect of olfactory functioning might be a reflection of a more objective odor evaluation model buffering emotional responses to environmental odors. PMID:18569576

  2. In vitro study of the biochemical origin and production limits of odorous compounds in cattle feedlots.

    PubMed

    Miller, D N; Varel, V H

    2001-12-01

    Livestock odors are closely correlated to airborne concentrations of volatile organic compounds (VOC), which are a complex mixture of carbon-, sulfur-, and nitrogen-containing compounds produced primarily during the incomplete anaerobic fermentation of animal manure by microorganisms. Volatile fatty acids, alcohols, and aromatic ring compounds comprise a substantial fraction of VOC, yet very little is known about their biochemical origin and environmental factors controlling their production. The anaerobic production of fermentation products and consumption of substrates (CP, starch, and nonstarch carbohydrate) were analyzed in slurries of fresh (< 24 h) and aged (> 1 d) cattle manure over several weeks. Ethanol, acetate, propionate, butyrate, lactate, and H2 were the major products of fermentation. Aged cattle manure produced twice the concentration of VFA during incubation produced by the fresh manure (P < 0.001). Aromatic compounds (phenols, indoles, and benzoates) remained unchanged in both manures. Production of VFA from fresh manure was inhibited when the pH fell below 4.5. It is likely that the presence of calcareous soil, which has a high buffering capacity, and lactate-consuming microorganisms minimized acidification in the aged manure slurries. Low starch content limited VFA production in the aged manure. Starch was the likely biochemical source for fermentation products in both manures based on the strong negative correlations between fermentation product and starch content (r = -0.944 and -0.773) and ratio of fermentation products produced to starch consumed (r = 0.64 and 0.72) for fresh and aged manure, respectively. Nonstarch carbohydrate served an indeterminate role in the production of fermentation products. Nonstarch carbohydrate decreased by 4.7 and 23.4 g/L in the fresh and aged manure, respectively, whereas the starch content decreased by 18.6 and 22.4 g/L in the fresh and aged manure, respectively. The concentration of CP did not change, which

  3. Characterization of potent odorants in male giant water bug (Lethocerus indicus Lep. and Serv.), an important edible insect of Southeast Asia.

    PubMed

    Kiatbenjakul, Patthamawadi; Intarapichet, Kanok-Orn; Cadwallader, Keith R

    2015-02-01

    Potent odorants in frozen fresh (FFB) and salted boiled (SBB) male giant water bugs (Lethocerus indicus), or 'Maengdana' in Thai, were characterized by application of direct solvent extraction/solvent-assisted flavour evaporation (SAFE), gas chromatography-mass spectrometry (GC-MS), gas chromatography-olfactometry (GC-O), aroma extract dilution analysis (AEDA) and stable isotope dilution assays (SIDA). Twenty and 27 potent odorants were detected in FFB and SBB, respectively. Most odorants were lipid-derived compounds, including the two most abundant volatile components (E)-2-hexenyl acetate and (E)-2-hexenyl butanoate, which contributed banana-like odours. 2-Acetyl-1-pyrroline and 2-acetyl-2-thiazoline, responsible for popcorn-like odours, were detected in SBB only. An aroma reconstitution model of SBB was constructed in an oil-in-water emulsion matrix using 12 selected potent odorants based on the results of AEDA, accurate compound quantification and the calculated odour-activity values (OAV). Omission studies were carried out to verify the significance of esters, particularly (E)-2-hexenyl acetate was determined to be an important character-impact odorant in male giant water bug aroma. PMID:25172758

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  5. Brooklyn Green, North Green, South Green, & West Green, parts ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Brooklyn Green, North Green, South Green, & West Green, parts of Brown Road, Canterbury Road (Route 169), Hartford Road (Route 6), Hyde Road, Pomfret Road (Route 169), Prince Hill Road, Providence Road (Route 6), Wauregan Road (Routes 169 & 205), & Wolf Den Road, Brooklyn, Windham County, CT

  6. An Odor Timer in Milk? Synchrony in the Odor of Milk Effluvium and Neonatal Chemosensation in the Mouse

    PubMed Central

    Al Aïn, Syrina; Belin, Laurine; Patris, Bruno; Schaal, Benoist

    2012-01-01

    Mammalian newborns exhibit avid responsiveness to odor compounds emanating from conspecific milk. Milk is however developmentally heterogeneous in composition as a function of both evolved constraints and offspring demand. The present study aimed to verify whether milk odor attractivity for neonates is equally distributed along lactation in Mus musculus (Balb-c strain). Therefore, we exposed pups varying in age to milk samples collected from females in different lactational stages. The pups were assayed at postnatal days 2 (P2), 6 (P6) and 15 (P15) in a series of paired-choice tests opposing either murine milk and a blank (water), or two samples of milk collected in different stages of lactation [lactation days 2 (L2), 6 (L6), and 15 L15)]. Pups of any age were able to detect, and were attracted to, the odor of the different milk. When milk from different lactational stages were simultaneously presented, P2 pups oriented for a similar duration to the odors of L2 and of L6 milk, but significantly less to the odor of L15 milk. Next, P6 pups roamed equivalently over L2 and L6 milk odors, but still less over the odor of L15 milk. Finally, P15 pups explored as much L15 milk odor as the odors of both L2 and L6 milk. This developmental shift in milk attractivity is discussed in terms of changing chemosensory properties of milk and of shifting chemosensory abilities/experience of pups. PMID:23133511

  7. A Female-Biased Odorant Receptor from Apolygus lucorum (Meyer-Dür) Tuned to Some Plant Odors.

    PubMed

    Zhang, Zhixiang; Zhang, Meiping; Yan, Shuwei; Wang, Guirong; Liu, Yang

    2016-01-01

    Apolygus lucorum (Meyer-Dür) (Hemiptera: Miridae) is a serious pest of cotton, jujube, grape and many other crops around the world. Understanding how olfactory information directs this insect to its host plants may provide environment-friendly approaches to the control of its population in agriculture. In our study, we cloned an odorant receptor gene, AlucOR46, that was specifically expressed in antennae and female-biased. Functional expression of AlucOR46 in Xenopus oocytes showed that it is tuned to six plant volatiles (S)-(-)-Limonene, (R)-(+)-Limonene, (E)-2-Hexenal, (E)-3-Hexenol, 1-Heptanol and (1R)-(-)-Myrtenol. Electroantennogram (EAG) recordings revealed that all six compounds could elicit electrophysiological responses from the antennae of A. lucorum, higher in females. Our results are in agreement with previous reports showing that (E)-2-Hexenal could attract female A. lucorum in behavior experiments. These results suggest that AlucOR46 might play an important role in locating the host plants of A. lucorum and therefore represents a suitable target for green pest control. PMID:27483241

  8. A Female-Biased Odorant Receptor from Apolygus lucorum (Meyer-Dür) Tuned to Some Plant Odors

    PubMed Central

    Zhang, Zhixiang; Zhang, Meiping; Yan, Shuwei; Wang, Guirong; Liu, Yang

    2016-01-01

    Apolygus lucorum (Meyer-Dür) (Hemiptera: Miridae) is a serious pest of cotton, jujube, grape and many other crops around the world. Understanding how olfactory information directs this insect to its host plants may provide environment-friendly approaches to the control of its population in agriculture. In our study, we cloned an odorant receptor gene, AlucOR46, that was specifically expressed in antennae and female-biased. Functional expression of AlucOR46 in Xenopus oocytes showed that it is tuned to six plant volatiles (S)-(−)-Limonene, (R)-(+)-Limonene, (E)-2-Hexenal, (E)-3-Hexenol, 1-Heptanol and (1R)-(−)-Myrtenol. Electroantennogram (EAG) recordings revealed that all six compounds could elicit electrophysiological responses from the antennae of A. lucorum, higher in females. Our results are in agreement with previous reports showing that (E)-2-Hexenal could attract female A. lucorum in behavior experiments. These results suggest that AlucOR46 might play an important role in locating the host plants of A. lucorum and therefore represents a suitable target for green pest control. PMID:27483241

  9. Fresh, Rayed Impact Crater

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-416, 9 July 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a fresh, young meteor impact crater on the martian surface. It is less than 400 meters (less than 400 yards) across. While there is no way to know the exact age of this or any other martian surface feature, the rays are very well preserved. On a planet where wind can modify surface features at the present time, a crater with rayed ejecta patterns must be very young indeed. Despite its apparent youth, the crater could still be many hundreds of thousands, if not several million, of years old. This impact scar is located within the much larger Crommelin Crater, near 5.6oN, 10.0oW. Sunlight illuminates the scene from the left.

  10. Detection of smoldering combustion of coal with an odor meter

    SciTech Connect

    Edwards, J.C.

    1995-05-01

    A commercially available odor meter was evaluated as a detector of smoldering coal combustion, and compared with incipient carbon monoxide (CO) and hydrogen sulfide (H{sub 2}S) detection and a commercially available ionization-type smoke detector. Ten smoldering coal combustion experiments were conducted. For eight of the experiments, Pittsburgh seam coal with an average particle diameter of approximately 5 cm was heated by embedded electrical strip heaters. For two of the experiments mine size Pittsburgh seam coal was heated. Heating rates of 0.5, 0.8, and 1.1. kw were selected to provide experimental conditions characteristic of very slow and moderately fast heating for coal sample mass between 3 and 10 kg. It was found that the odor meter and smoke detector alarm had a good correlation, with the odor meter alarm occurring prior to the smoke alarm in four of the ten experiments. The odor meter gave an increase in its output signal above ambient equivalent to detecting 1 ppm of H{sub 2}S (ten times the odor threshold of H{sub 2}S) as an alarm value. This observed odor meter response occurred prior to the electrochemical detection of H{sub 2}S for five of the six experiments for which it was evaluated. In all six experiments for which the smoke optical density was evaluated, it was less than 0.023 m{sup -1} prior to the odor meter reaching alarm. In each of the eight experiments with 5 cm diameter coal particles the CO exceeded 5 ppm at odor meter alarm, while for the two experiments with mine size coal the CO was less than 3 ppm at odor meter alarm. The odor meter, as tested, is not a significant improvement over smoke and CO detectors. Because the odor meter responds to a variety of chemical compounds, with suitable modification and increased sensitivity it may be useful for detection of mine fires and thereby enhance mine safety.

  11. The effect of a salient odor context on memory retrieval in young infants.

    PubMed

    Schroers, Melissa; Prigot, Joyce; Fagen, Jeffrey

    2007-12-01

    Three-month-old infants were trained to move a mobile in the presence of a coconut or cherry odor (context). One or 5 days later, the infants were tested for retrieval in the presence of either the same odor, the alternate odor, or no odor. Infants tested with the training odor displayed retention at both intervals; retention was not seen at either interval in the alternate odor or no odor conditions. These data suggest that the odor combines with the mobile to form a compound-stimulus representation of the learned task whose presence after both short (1 day) and long (5 days) intervals is a necessary retrieval cue. PMID:17599418

  12. The Effect of a Salient Odor Context on Memory Retrieval in Young Infants

    PubMed Central

    Schroers, Melissa; Prigot, Joyce; Fagen, Jeffrey

    2007-01-01

    Three-month-old infants were trained to move a mobile in the presence of a coconut or cherry odor (context). 1 or 5 days later, the infants were tested for retrieval in the presence of either the same odor, the alternate odor, or no odor. Infants tested with the training odor displayed retention at both intervals; retention was not seen at either interval in the alternate odor or no odor conditions. These data suggest that the odor combines with the mobile to form a compound-stimulus representation of the learned task whose presence after both short (1 day) and long (5 days) intervals is a necessary retrieval cue. PMID:17599418

  13. Animal-to-Animal Variation in Odor Preference and Neural Representation of Odors

    NASA Astrophysics Data System (ADS)

    Honegger, Kyle; Smith, Matthew; Turner, Glenn; de Bivort, Benjamin

    Across any population of animals, individuals exhibit diverse behaviors and reactions to sensory stimuli like tastes and odors. While idiosyncratic behavior is ubiquitous, its biological basis is poorly understood. In this talk, I will present evidence that individual fruit flies (Drosophila melanogaster) display idiosyncratic olfactory behaviors and discuss our ongoing efforts to map these behavioral differences to variation in neural circuits. Using a high-throughput, single-fly assay for odor preference, we have demonstrated that highly inbred flies display substantial animal-to-animal variability, beyond that expected from experimental error, and that these preferences persist over days. Using in vivo two-photon calcium imaging, we are beginning to examine the idiosyncrasy of neural coding in the fly olfactory pathway and find that the odor responses of individual processing channels in the antennal lobe can vary substantially from fly to fly. These results imply that individual differences in neural coding may be used to predict the idiosyncratic behavior of an individual - a hypothesis we are currently testing by imaging neural activity from flies after measuring their odor preferences.

  14. Odor and odorous chemical emissions from animal buildings: part 4-correlations between sensory and chemical measurements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study supplemented the National Air Emissions Monitoring Study (NAEMS) with one year of comprehensive measurements of odor emission at five swine and four dairy buildings. The measurements included both standard human sensory measurements using dynamic forced-choice olfactometry and chemical an...

  15. Odor and odorous chemical emissions from animal buildings: Part 4 - correlations between sensory and chemical measurements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study supplemented the National Air Emissions Monitoring Study (NAEMS) by making comprehensive measurements, over a full calendar year, of odor emissions from five swine and four dairy rooms/buildings (subset of the total number of buildings monitored for the NAEMS project). The measurements ma...

  16. Chemical analysis of human odor and other animal odors to identify kairomones and allomones of mosquitoes.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Semiochemicals emitted by hosts of mosquitoes seeking a blood meal can lead to the attraction or avoidance of a host. Examination of the odor profiles from different hosts can lead to the identification of candidate kairomones and allomones affecting mosquitoes. This presentation will cover the ch...

  17. Antioxidant properties of natural substances in irradiated fresh poultry

    NASA Astrophysics Data System (ADS)

    Mahrour, A.; Lacroix, M.; Nketsa-Tabiri, J.; Calderon, N.; Calderon, R.; Gagnon, M.

    1998-06-01

    This study was undertaken to determine if a combined treatment (marinating in natural plant extracts or vacuum) with irradiation could have a synergistic effect, in order to prevent the lipid oxidation resulting in the development of undesirable flavours. The fresh chicken legs were irradiated at 0,3 and 5 kGy. The fatty acids composition of lipids was identified using gas liquid chromatography. The effect of irradiation treatment combined with a pre-treatment on the fatty acids composition was followed. The day after irradiation, ten panallists were asked to evaluate, using the instruction scaling, the overall appearance, the odor, the flavor and the overall acceptability of the samples. The major fatty acids identified in lipids were oleic acid, palmitic acid, palmitoleic acid and stearic acid. Pre-treatments have a significant effect on linoleic acid (C18:2) and higher fatty acids. The unsaturated fatty acids derived from phospholipids appeared to be more affected by the irradiation dose: however, marinating have better protection on C18:2 derived from phospholipids. The results of sensory evaluation have shown a significant better odor and flavor for the irradiated chicken at 5 kGy than the control. No significant difference have been found between the marinated chicken, the chicken irradiated under vacuum and the control.

  18. Light-weight analyzer for odor recognition

    DOEpatents

    Vass, Arpad A; Wise, Marcus B

    2014-05-20

    The invention provides a light weight analyzer, e.g., detector, capable of locating clandestine graves. The detector utilizes the very specific and unique chemicals identified in the database of human decompositional odor. This detector, based on specific chemical compounds found relevant to human decomposition, is the next step forward in clandestine grave detection and will take the guess-work out of current methods using canines and ground-penetrating radar, which have historically been unreliable. The detector is self contained, portable and built for field use. Both visual and auditory cues are provided to the operator.

  19. Crystal structures of bovine odorant-binding protein in complex with odorant molecules.

    PubMed

    Vincent, Florence; Ramoni, Roberto; Spinelli, Silvia; Grolli, Stefano; Tegoni, Mariella; Cambillau, Christian

    2004-10-01

    The structure of bovine odorant-binding protein (bOBP) revealed a striking feature of a dimer formed by domain swapping [Tegoni, M., Ramoni, R., Bignetti, E., Spinelli, S. & Cambillau, C. (1996) Nat. Struct. Biol.3, 863-867; Bianchet, M.A., Bains, G., Pelosi, P., Pevsner, J., Snyder, S.H., Monaco, H.L. & Amzel, L.M. (1996) Nat. Struct. Biol.3, 934-939] and the presence of a naturally occuring ligand [Ramoni, R., Vincent, F., Grolli, S., Conti, V., Malosse, C., Boyer, F.D., Nagnan-Le Meillour, P., Spinelli, S., Cambillau, C. & Tegoni, M. (2001) J. Biol. Chem.276, 7150-7155]. These features led us to investigate the binding of odorant molecules with bOBP in solution and in the crystal. The behavior of odorant molecules in bOBP resembles that observed with porcine OBP (pOBP), although the latter is monomeric and devoid of ligand when purified. The odorant molecules presented K(d) values with bOBP in the micromolar range. Most of the X-ray structures revealed that odorant molecules interact with a common set of residues forming the cavity wall and do not exhibit specific interactions. Depending on the ligand and on the monomer (A or B), a single residue--Phe89--presents alternate conformations and might control cross-talking between the subunits. Crystal data on both pOBP and bOBP, in contrast with binding and spectroscopic studies on rat OBP in solution, reveal an absence of significant conformational changes involving protein loops or backbone. Thus, the role of OBP in signal triggering remains unresolved. PMID:15373829

  20. Development Switch in Neural Circuitry Underlying Odor-Malaise Learning

    ERIC Educational Resources Information Center

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

    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…

  1. Multiple activities of insect repellents on odorant receptors in mosquitoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several lines of evidence suggest that insect repellent molecules reduce mosquito-host contacts by interacting with odorants and odorant receptors (ORs) ultimately affecting olfactory-driven behaviors. We describe the molecular effects of ten insect repellents and a pyrethroid insecticide with known...

  2. Origins and identities of key manure odor components

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Odor is just one of many environmental issues associated with animal manures. Odor arises from a number of different locations in animal production systems, but the chemistry and biochemical origin is similar across sites. A complex mixture of volatile organic compounds (VOC) and inorganic compoun...

  3. Odor Mitigation with Tree Buffers: Swine Production Case Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tree buffers are a potential low cost sustainable odor mitigation strategy, but there is little to no data on their effectiveness. Odor transport is thought to occur one of two ways either directly through vapor phase transport or indirectly through sorption onto particles. Consequently, monitoring...

  4. Influence of manure application method on odor emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surface application of manure in reduced tillage systems can serve as a major source of nuisance odors. An investigation was undertaken to evaluate odor emissions associated with various technologies that incorporate manure with minimal soil disturbance. Dairy manure slurry was applied by five meth...

  5. 77 FR 22381 - Odorant Fade in Railroad Tank Cars

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-13

    ...FRA is issuing Safety Advisory 2012-01 to remind shippers and consignees of railroad tank cars containing odorized liquefied petroleum gas (LPG), of the importance of taking actions to ensure that a sufficient level of odorant remains in the LPG throughout the entire transportation cycle. FRA is issuing this notice to raise awareness within the hazardous materials community, of the potential......

  6. Automated Method for Analysis of 18 Odorants in Swine Manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Air quality in rural communities is potentially impacted by waste products from animal production facilities. Determining the types and levels of odorants in waste material is needed if proper odor abatement strategies are to be developed. However, analysis of waste material is difficult and tedio...

  7. Semantic context facilitates odor identification in children and adults.

    PubMed

    Goubet, Nathalie; McCall, Daniel D; Ducz, Jennifer K; Bingham, Megan L

    2014-04-01

    The current study investigated the influence of semantic cues on odor identification in preschool-aged children and adults. We tested the hypothesis that odor identification in a multiple-choice task is facilitated when choices belong to different semantic categories compared to when they belong to the same category. Participants were shown three color pictures, one of which represented the target odor and the other two depicted items that were either from the same or different semantic categories as the target odor. After smelling the target odor, participants were asked to identify the odor they had just smelled by pointing to one of the three pictures. Results indicated that while adults outperformed children, performance in both age groups was better when the picture of the target odor was semantically unrelated to the foil pictures. These data support the idea that well-known deficits in odor identification may result from weak associations between the olfactory percept and semantic memory rather than from poor olfactory perception per se. PMID:23775043

  8. ODOR CONTROL BY SCRUBBING IN THE RENDERING INDUSTRY. (ADDENDUM)

    EPA Science Inventory

    The report gives results of a study extending an earlier project during which an investigation of the performance of packed-bed scrubbers for high-intensity rendering plant odors (5000 to 180,000 odor units) showed that, although in some cases the removal was as high as 99%, the ...

  9. Odorous VOC emissions following land application of swine manure slurry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Swine manure is often applied to crop land as a fertilizer source. Odor emissions from land-applied swine manure may pose a possible nuisance to downwind populations if not applied with sufficient forethought. A research project was conducted to assess the time decay of odorous volatile organic co...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  11. Characterization and dispersion modeling of odors from a piggery facility.

    PubMed

    Karageorgos, Petros; Latos, Manolis; Mpasiakos, Christos; Chalarakis, Elefterios; Dimitrakakis, Emmanuel; Daskalakis, Charis; Psillakis, Elefteria; Lazaridis, Mihalis; Kalogerakis, Nicolas

    2010-01-01

    Piggeries are known for their nuisance odors, creating problems for workers and nearby residents. Chemical substances that contribute to these odors include sulfurous organic compounds, hydrogen sulfide, phenols and indoles, ammonia, volatile amines, and volatile fatty acids. In this work, daily mean concentrations of ammonia (NH3) and hydrogen sulfide (H2S) were measured by hand-held devices. Measurements were taken in several places within the facility (farrowing to finishing rooms). Hydrogen sulfide concentration was found to be 40 to 50 times higher than the human odor threshold value in the nursery and fattening room, resulting in strong nuisance odors. Ammonia concentrations ranged from 2 to 18 mL m(-3) and also contributed to the total odor nuisance. Emission data from various chambers of the pig farm were used with the dispersion model AERMOD to determine the odor nuisance caused due to the presence of H2S and NH3 to receptors at various distances from the facility. Because just a few seconds of exposure can cause an odor nuisance, a "peak-to-mean" ratio was used to predict the maximum odor concentrations. Several scenarios were examined using the modified AERMOD program, taking into account the complex terrain around the pig farm. PMID:21284315

  12. 46 CFR 193.15-17 - Odorizing units.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Odorizing units. 193.15-17 Section 193.15-17 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-17 Odorizing units. Each carbon dioxide extinguishing...

  13. The Influence of Trigeminal Stimulation on Children's Judgements of Odor.

    ERIC Educational Resources Information Center

    Engen, Trygg; Moskowitz, Linda

    Children's preference for odors, some of which presumably had marked trigeminal (noxious) effects, was assessed with the use of the method of pair comparison. Although the children, from 4 to 7 years old, were able to discriminate between the intensities of the odors, they were neither attracted nor repelled by them as much as the adults. In other…

  14. Perception of environmental tobacco smoke odors: An olfactory and visual response

    NASA Astrophysics Data System (ADS)

    Moschandreas, D. J.; Relwani, S. M.

    Odor perception of approximately 200 subjects was measured to determine whether visual contact with an odor source affects sensory responses and to estimate the magnitude of such an effect. Environmental tobacco smoke (ETS) odors were generated in a chamber either by a smoke machine or by an investigator who smoked. Several levels of odor intensity were generated. Odor intensity, odor hedonics and odor characters were the parameters measured before and after visual contact with the odor source. Visual contact increased the perceived odor intensity, the hedonic nature of the odor changed directionally toward unpleasant and the number of subjects perceiving tobacco odor increased. The change caused by visual contact led to differences that were statistically significant.

  15. Urban air pollution by odor sources: Short time prediction

    NASA Astrophysics Data System (ADS)

    Pettarin, Nicola; Campolo, Marina; Soldati, Alfredo

    2015-12-01

    A numerical approach is proposed to predict the short time dispersion of odors in the urban environment. The model is based on (i) a three dimensional computational domain describing the urban topography at fine spatial scale (1 m) and on (ii) highly time resolved (1 min frequency) meteorological data used as inflow conditions. The time dependent, three dimensional wind velocity field is reconstructed in the Eulerian framework using a fast response finite volume solver of Navier-Stokes equations. Odor dispersion is calculated using a Lagrangian approach. An application of the model to the historic city of Verona (Italy) is presented. Results confirm that this type of odor dispersion simulations can be used (i) to assess the impact of odor emissions in urban areas and (ii) to evaluate the potential mitigation produced by odor abatement systems.

  16. Fresh Veggies from Space

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Professor Marc Anderson of the University of Wisconsin-Madison developed a technology for use in plant-growth experiments aboard the Space Shuttle. Anderson's research and WCSAR's technology were funded by NASA and resulted in a joint technology licensed to KES Science and Technology, Inc. This transfer of space-age technology resulted in the creation of a new plant-saving product, an ethylene scrubber for plant growth chambers. This innovation presents commercial benefits for the food industry in the form of a new device, named Bio-KES. Bio-KES removes ethylene and helps to prevent spoilage. Ethylene accounts for up to 10 percent of produce losses and 5 percent of flower losses. Using Bio-KES in storage rooms and displays will increase the shelf life of perishable foods by more than one week, drastically reducing the costs associated with discarded rotten foods and flowers. The savings could potentially be passed on to consumers. For NASA, the device means that astronauts can conduct commercial agricultural research in space. Eventually, it may also help to grow food in space and keep it fresh longer. This could lead to less packaged food being taken aboard missions since it could be cultivated in an ethylene-free environment.

  17. Analysis of the cooked aroma and odorants that contribute to umami aftertaste of soy miso (Japanese soybean paste).

    PubMed

    Inoue, Yutaka; Kato, Sachie; Saikusa, Miyu; Suzuki, Chihiro; Otsubo, Yuriko; Tanaka, Yutaro; Watanabe, Hirohito; Hayase, Fumitaka

    2016-12-15

    Soy miso, the traditional Japanese fermented soybean paste prepared using soybean koji, is used for imparting umami aftertaste to cooked dishes. The objective of this study was to identify the key odorants of cooked soy miso and their influence on umami aftertaste perception. Volatile compounds of soy miso and two rice misos were prepared using simultaneous distillation-extraction, and the key odorants were identified by using the gas chromatography-olfactometry/aroma extract dilution assay approach, and soy miso was compared with rice misos. Forty-one aroma-active compounds were detected in cooked soy miso, and malty, green, roasty and sulfury aromas were identified as the characteristic aromas. Finally, sensory evaluation was conducted to assess the contribution to the umami aftertaste of six key compounds with the highest flavour dilution factor. Results revealed that dimethyl trisulfide, which was newly identified in cooked miso, contributes to the umami aftertaste and palatability of cooked soy miso. PMID:27451212

  18. Microbial safety of fresh produce

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The book entitled “Microbial Safety of Fresh Produce” with 23 chapters is divided into following six sections: Microbial contamination of fresh produce, Pre-harvest strategies, post-harvest interventions, Produce safety during processing and handling, Public, legal, and economic Perspectives, and Re...

  19. Use of an integrated approach to characterize the physicochemical properties of foundry green sands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A fresh green sand, spent green sand, and a weathered spent green sand from a landfill were analyzed using diffractometry, electron microscopy, granulometry, spectrometry, and thermogravimetry. Our objective was to understand how the physicochemical properties of the green sands change from their o...

  20. A Sensory 3D Map of the Odor Description Space Derived from a Comparison of Numeric Odor Profile Databases.

    PubMed

    Zarzo, Manuel

    2015-06-01

    Many authors have proposed different schemes of odor classification, which are useful to aid the complex task of describing smells. However, reaching a consensus on a particular classification seems difficult because our psychophysical space of odor description is a continuum and is not clustered into well-defined categories. An alternative approach is to describe the perceptual space of odors as a low-dimensional coordinate system. This idea was first proposed by Crocker and Henderson in 1927, who suggested using numeric profiles based on 4 dimensions: "fragrant," "acid," "burnt," and "caprylic." In the present work, the odor profiles of 144 aroma chemicals were compared by means of statistical regression with comparable numeric odor profiles obtained from 2 databases, enabling a plausible interpretation of the 4 dimensions. Based on the results and taking into account comparable 2D sensory maps of odor descriptors from the literature, a 3D sensory map (odor cube) has been drawn up to improve understanding of the similarities and dissimilarities of the odor descriptors most frequently used in fragrance chemistry. PMID:25847969

  1. Acute Atrazine Exposure has Lasting Effects on Chemosensory Responses to Food Odors in Crayfish (Orconectes virilis).

    PubMed

    Belanger, Rachelle M; Mooney, Lauren N; Nguyen, Hung M; Abraham, Noor K; Peters, Tyler J; Kana, Maria A; May, Lauren A

    2016-02-01

    The herbicide atrazine is known to impact negatively olfactory-mediated behaviors in aquatic animals. We have shown that atrazine exposure has deleterious effects on olfactory-mediated behavioral responses to food odors in crayfish; however, recovery of chemosensory abilities post-atrazine exposure has not been investigated. We examined whether crayfish (Orconectes virilis) recovered chemosensory abilities after a 96-h exposure to sublethal, environmentally relevant concentrations of 80 ppb (µg/L) atrazine. Following treatment, we analyzed the ability of the crayfish to locate a food source using a Y-maze with one arm containing fish-flavored gelatin and the other containing unflavored gelatin. We compared the time spent in the food arm of the Y-maze, near the food source, as well as moving and walking speed of control and atrazine-treated crayfish. We also compared the number of crayfish that handled the food source and the amount of food consumed. Following 24-, 48-, and 72-h recovery periods in fresh water, behavioral trials were repeated to determine if there was any observable recovery of chemosensory-mediated behaviors. Atrazine-treated crayfish spent less time in the food arm, at the odor source, and were less successful at finding the food odor source than control crayfish for all times tested. Additionally, atrazine-treated crayfish consumed less fish-flavored than control crayfish; however, treatment did not affect locomotion. Overall, we found that crayfish are not able to recover chemosensory abilities 72 h post-atrazine exposure. Because crayfish rely heavily on their chemosensory abilities to acquire food, the negative impacts of atrazine exposure could affect population size in areas where atrazine is heavily applied. PMID:26487338

  2. Green Coffee

    MedlinePlus

    ... Talk with your health provider.Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)Caffeine in green coffee might slow blood clotting. Taking green coffee along with medications that also ...

  3. Green Tea

    MedlinePlus

    ... gov Key References Green tea. Natural Medicines Comprehensive Database Web site. Accessed at www.naturaldatabase.com on July 8, 2009. Green tea ( Camellia sinensis ). Natural Standard Database Web site. Accessed at www.naturalstandard.com on July ...

  4. Concentrations of aroma compounds and odor activity values of odorant series in different olive cultivars and their oils.

    PubMed

    Reboredo-Rodríguez, Patricia; González-Barreiro, Carmen; Cancho-Grande, Beatriz; Simal-Gándara, Jesús

    2013-06-01

    Olives from Picual, Arbequina, Manzanilla de Sevilla, and Local cultivars together with their corresponding oils were analyzed in terms of odor activity values (OAVs) to establish the relationship between the aromatic profile of both olives and oils. The OAVs for the different compounds were classified in nine odorant series: grass, leaf, wood, bitter, sweet, pungent, olive fruit, apple, and banana. The total intensities for every aromatic series were calculated as the sum of the OAVs of each compound associated with this series. As a result, olives had characteristic profiles. Picual cultivar had not a clear sensory characterization from the volatile compounds. Arbequina cultivar was mainly characterized by apple and bitter odorant series; Manzanilla de Sevilla by apple, bitter, and grass odorant series; and Local variety by banana and olive fruit. However, in the oils obtained from those olives, these differences disappeared, and all oils showed the same profile with pungent, bitter, and wood odorant series most strongly contributing. PMID:23659432

  5. Empirical model of odor emission from deep-pit swine finishing barns to derive a standardized odor emission factor

    NASA Astrophysics Data System (ADS)

    Schauberger, Günther; Lim, Teng-Teeh; Ni, Ji-Qin; Bundy, Dwaine S.; Haymore, Barry L.; Diehl, Claude A.; Duggirala, Ravi K.; Heber, Albert J.

    2013-02-01

    Odor emission from swine housing is influenced by the herd characteristics and building environment. The following three specific factors were identified as inputs to a swine house odor emission model: indoor temperature, barn ventilation rate, and pig activity. Model input parameters were determined based on tests of four, identical, 1000-head, mechanically-ventilated swine finishing houses. Each building had two sidewall curtains, a curtain on the west end wall, five exhaust fans on the east end wall, four pit ventilation fans, and long-term manure storage beneath a fully slatted floor. Odor concentrations of 112 odor samples were determined using dynamic forced-choice olfactometry with four to six trained panelists. The emission model showed that the standard live mass specific odor emission factor was 48 OU s-1 per 500 kg live mass or animal unit (AU), and it corresponded to an indoor temperature of T0 = 20 °C, a ventilation rate of V0 = 200 m3 h-1 (55.6 × 10-3 m3 s-1) per pig (maximum capacity for summer time), and the daily mean animal activity. The rate of odor emission from a swine finishing house can be calculated based on these parameters coupled with the number of animals, the mean live mass, and the standard live mass specific odor emission factor. Using this process-based odor emission model, the odor emission estimation and therefore the input for odor dispersion models can be improved to obtain more reliable estimates of separation distance for siting future pig farms.

  6. Exposure to odors of rivals enhances sexual motivation in male giant pandas.

    PubMed

    Bian, Xiaoxing; Liu, Dingzhen; Zeng, Hua; Zhang, Guiquan; Wei, Rongping; Hou, Rong

    2013-01-01

    Males will alter their mating behavior to cope with the presence of their competitors. Even exposure to odors from potential competitors can greatly increase male ejaculate expenditure in a variety of animals including insects, fishes, birds and rodents. Major efforts have been made to examine males' plastic responses to sperm competition and its fitness benefits. However, the effects of competitor absence on male's sexual motivation and behaviors remain unclear, which has been proposed to be one of the causes for the poor sexual performance of some captive mammals. This study revealed that sexual motivation can be greatly enhanced in captive male giant pandas (Ailuropoda melanoleuca) by exposure to chemosensory cues from either one or three conspecifics males. It had been shown that potential rivals' odors increased males' chemosensory investigation behavior, as well as their observing, following and sniffing behaviors towards estrous females. Behaviors changed regardless of the number of rivals (one or three). Our results demonstrate the effects of potential competition on male giant pandas' sexual motivation and behavioral coping strategy. We anticipate that our research will provide a fresh insight into the mechanisms underlying poor sexual performance in male captive mammals, and valuable information for the practical management and ex situ conservation of endangered species. PMID:23940532

  7. Exposure to Odors of Rivals Enhances Sexual Motivation in Male Giant Pandas

    PubMed Central

    Bian, Xiaoxing; Liu, Dingzhen; Zeng, Hua; Zhang, Guiquan; Wei, Rongping; Hou, Rong

    2013-01-01

    Males will alter their mating behavior to cope with the presence of their competitors. Even exposure to odors from potential competitors can greatly increase male ejaculate expenditure in a variety of animals including insects, fishes, birds and rodents. Major efforts have been made to examine males' plastic responses to sperm competition and its fitness benefits. However, the effects of competitor absence on male's sexual motivation and behaviors remain unclear, which has been proposed to be one of the causes for the poor sexual performance of some captive mammals. This study revealed that sexual motivation can be greatly enhanced in captive male giant pandas (Ailuropoda melanoleuca) by exposure to chemosensory cues from either one or three conspecifics males. It had been shown that potential rivals' odors increased males' chemosensory investigation behavior, as well as their observing, following and sniffing behaviors towards estrous females. Behaviors changed regardless of the number of rivals (one or three). Our results demonstrate the effects of potential competition on male giant pandas' sexual motivation and behavioral coping strategy. We anticipate that our research will provide a fresh insight into the mechanisms underlying poor sexual performance in male captive mammals, and valuable information for the practical management and ex situ conservation of endangered species. PMID:23940532

  8. Acquired Smell? Mature Females of the Common Green Bottle Fly Shift Semiochemical Preferences from Feces Feeding Sites to Carrion Oviposition Sites.

    PubMed

    Brodie, Bekka S; Babcock, Tamara; Gries, Regine; Benn, Arlan; Gries, Gerhard

    2016-01-01

    We investigated foraging decisions by adult females of the common green bottle fly, Lucilia sericata, in accordance with their physiological state. When we gave female flies a choice between visually occluded, fresh canine feces (feeding site) and a CO2-euthanized rat (carrion oviposition site), 3-d-old "protein-starved" females responded equally well to feces and carrion, whereas protein-fed gravid females with mature oocytes responded only to carrion, indicating resource preferences based on a fly's physiological state. Dimethyl trisulfide (DMTS) is known to attract gravid L. sericata females to carrion. Therefore, we analyzed headspace from canine feces by gas chromatographic-electroantennographic detection (GC-EAD) and GC/mass spectrometry. In bioassays, of the 17 fecal odorants that elicited GC-EAD responses from fly antennae, a blend of indole and one or more of the alcohols phenol, m-/p-cresol and 1-octen-3-ol proved as attractive to flies as canine feces. Unlike young females, gravid females need to locate carrion for oviposition and distinguish between fresh and aging carrion, the latter possibly detrimental to offspring. Gravid female L. sericata accomplish this task, in part, by responding to trace amounts of DMTS emanating from fresh carrion and by discriminating against carrion as soon it begins to produce appreciable amounts of indole, which is also the second-most abundant semiochemical in fresh canine feces, and apparently serves as an indicator of food rather than oviposition resources. Our results emphasize the importance of studying foraging choices by flies in accordance with their physiological stage. PMID:26637207

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

    ERIC Educational Resources Information Center

    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…

  10. Research on Odor Interaction between Aldehyde Compounds via a Partial Differential Equation (PDE) Model

    PubMed Central

    LuchunYan; Liu, Jiemin; Qu, Chen; Gu, Xingye; Zhao, Xia

    2015-01-01

    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. PMID:25635413

  11. Molecular Tuning of Odorant Receptors and Its Implication for Odor Signal Processing

    PubMed Central

    Reisert, Johannes

    2009-01-01

    The discovery of the odorant receptor (OR) family by Buck and Axel in 1991 provided a quantum jump in our understanding of olfactory function. However, the study of the responsiveness of ORs to odor ligands was challenging due to the difficulties in deorphanizing the receptors. In this manuscript, we review recent findings of OR responsiveness that have come about through improved OR deorphanization methods, site-directed mutagenesis, structural modeling studies, and studies of OR responses in situ in olfactory sensory neurons. Although there has been a major leap in our understanding of receptor–ligand interactions and how these contribute to the input to the olfactory system, an improvement of our understanding of receptor structure and dynamics and interactions with intracellular and extracellular proteins is necessary. PMID:19525317

  12. The impact of natural odors on affective states in humans.

    PubMed

    Weber, Sandra T; Heuberger, Eva

    2008-06-01

    Laboratory studies have shown a significant influence of certain fragrances on affective as well as cognitive states in humans. The aim of the current study was to measure the relationship between complex, natural odors and affective states, that is, calmness, alertness, and mood, in the field. In 4 experiments, the emotional impact, intensity, and hedonics of complex, natural plant odors were assessed in 32 healthy human subjects and compared with control conditions involving a similar outdoor environment without the tested fragrant plants. In all experiments, the selected fragrances were evaluated as more intense than the odors in the control conditions but pleasantness ratings differed only in 2 of the 4 experiments. The fragrances improved subjective ratings of calmness, alertness, and mood depending on the sequence of the conditions but independent of visual features of the environment. In contrast, a fifth experiment which tested the influence of natural and artificial pleasant odors and an artificial unpleasant odor on calmness, alertness, and mood in 22 subjects showed that the unpleasant odor impaired these affective states in humans independent of the order of presentation. On the other hand, no effects of the pleasant odors on mood and calmness were observed in this experiment. PMID:18353767

  13. Multidimensional representation of odors in the human olfactory cortex.

    PubMed

    Fournel, A; Ferdenzi, C; Sezille, C; Rouby, C; Bensafi, M

    2016-06-01

    What is known as an odor object is an integrated representation constructed from physical features, and perceptual attributes mainly mediated by the olfactory and trigeminal systems. The aim of the present study was to comprehend how this multidimensional representation is organized, by deciphering how similarities in the physical, olfactory and trigeminal perceptual spaces of odors are represented in the human brain. To achieve this aim, we combined psychophysics, functional MRI and multivariate representational similarity analysis. Participants were asked to smell odors diffused by an fMRI-compatible olfactometer and to rate each smell along olfactory dimensions (pleasantness, intensity, familiarity and edibility) and trigeminal dimensions (irritation, coolness, warmth and pain). An event-related design was implemented, presenting different odorants. Results revealed that (i) pairwise odorant similarities in anterior piriform cortex (PC) activity correlated with pairwise odorant similarities in chemical properties (P < 0.005), (ii) similarities in posterior PC activity correlated with similarities in olfactory perceptual properties (P <0.01), and (iii) similarities in amygdala activity correlated with similarities in trigeminal perceptual properties (P < 0.01). These findings provide new evidence that extraction of physical, olfactory and trigeminal features is based on specific fine processing of similarities between odorous stimuli in a distributed manner in the olfactory system. Hum Brain Mapp 37:2161-2172, 2016. © 2016 Wiley Periodicals, Inc. PMID:26991044

  14. Rapid odor perception in rat olfactory bulb by microelectrode array.

    PubMed

    Zhou, Jun; Dong, Qi; Zhuang, Liu-jing; Li, Rong; Wang, Ping

    2012-12-01

    Responses of 302 mitral/tufted (M/T) cells in the olfactory bulb were recorded from 42 anesthetized freely breathing rats using a 16-channel microwire electrode array. Saturated vapors of four pure chemicals, anisole, carvone, citral and isoamyl acetate were applied. After aligning spike trains to the initial phase of the inhalation after odor onset, the responses of M/T cells showed transient temporal features including excitatory and inhibitory patterns. Both odor-evoked patterns indicated that mammals recognize odors within a short respiration cycle after odor stimulus. Due to the small amount of information received from a single cell, we pooled results from all responsive M/T cells to study the ensemble activity. The firing rates of the cell ensembles were computed over 100 ms bins and population vectors were constructed. The high dimension vectors were condensed into three dimensions for visualization using principal component analysis. The trajectories of both excitatory and inhibitory cell ensembles displayed strong dynamics during odor stimulation. The distances among cluster centers were enlarged compared to those of the resting state. Thus, we presumed that pictures of odor information sent to higher brain regions were depicted and odor discrimination was completed within the first breathing cycle. PMID:23225857

  15. Odor quality coding and categorization in human posterior piriform cortex

    PubMed Central

    Howard, James D; Plailly, Jane; Grueschow, Marcus; Haynes, John-Dylan; Gottfried, Jay A

    2010-01-01

    Efficient recognition of odorous objects universally shapes animal behavior and is crucial for survival. To distinguish kin from non-kin, mate from non-mate, food from non-food, organisms must be able to create meaningful perceptual representations of odor qualities and categories. It is currently unknown where, and in what form, the brain encodes information about odor quality. By combining functional magnetic resonance imaging (fMRI) with multivariate (pattern-based) techniques, we show that spatially distributed ensemble activity in human posterior piriform cortex (PPC) coincides with perceptual ratings of odor quality, such that odorants with more (or less) similar fMRI patterns were perceived as more (or less) alike. Critically, these effects were not observed in anterior piriform cortex, amygdala, or orbitofrontal cortex, demonstrating that ensemble coding of odor categorical perception is regionally specific for PPC. These findings substantiate theoretical models emphasizing the importance of distributed piriform templates for the perceptual reconstruction of odor object quality. PMID:19483688

  16. Blocking and the detection of odor components in blends.

    PubMed

    Hosler, J S; Smith, B H

    2000-09-01

    Recent studies of olfactory blocking have revealed that binary odorant mixtures are not always processed as though they give rise to mixture-unique configural properties. When animals are conditioned to one odorant (A) and then conditioned to a mixture of that odorant with a second (X), the ability to learn or express the association of X with reinforcement appears to be reduced relative to animals that were not preconditioned to A. A recent model of odor-based response patterns in the insect antennal lobe predicts that the strength of the blocking effect will be related to the perceptual similarity between the two odorants, i.e. greater similarity should increase the blocking effect. Here, we test that model in the honeybee Apis mellifera by first establishing a generalization matrix for three odorants and then testing for blocking between all possible combinations of them. We confirm earlier findings demonstrating the occurrence of the blocking effect in olfactory learning of compound stimuli. We show that the occurrence and the strength of the blocking effect depend on the odorants used in the experiment. In addition, we find very good agreement between our results and the model, and less agreement between our results and an alternative model recently proposed to explain the effect. PMID:10952879

  17. Scopolamine Enhances Generalization between Odor Representations in Rat Olfactory Cortex

    PubMed Central

    Wilson, Donald A.

    2001-01-01

    Acetylcholine (ACh) has a critical, modulatory role in plasticity in many sensory systems. In the rat olfactory system, both behavioral and physiological data indicate that ACh may be required for normal odor memory and synaptic plasticity. Based on these data, neural network models have hypothesized that ACh muscarinic receptors reduce interference between learned cortical representations of odors within the piriform cortex. In this study, odor receptive fields of rat anterior piriform cortex (aPCX) single-units for alkane odors were mapped before and after either a systemic injection of the muscarinic receptor antagonist scopolamine (0.5 mg/kg) or aPCX surface application of 500 μM scopolamine (or saline/ACSF controls). Cross-habituation between alkanes differing by two to four carbons was then examined following a 50-sec habituating stimulus. The results demonstrate that neither aPCX spontaneous activity nor odor-evoked activity (receptive field) was affected by scopolamine, but that cross-habituation in aPCX neurons was enhanced significantly by either systemic or cortical scopolamine. These results indicate that scopolamine selectively enhances generalization between odor representations in aPCX in a simple memory task. Given that ACh primarily affects intracortical association fibers in the aPCX, the results support a role for the association system in odor memory and discrimination and indicate an important ACh modulatory control over this basic sensory process. PMID:11584075

  18. Effects of Visual Priming on Taste-Odor Interaction

    PubMed Central

    van Beilen, Marije; Bult, Harold; Renken, Remco; Stieger, Markus; Thumfart, Stefan; Cornelissen, Frans; Kooijman, Valesca

    2011-01-01

    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. PMID:21969852

  19. Characterization and coding of behaviorally significant odor mixtures.

    PubMed

    Riffell, Jeffrey A; Lei, Hong; Christensen, Thomas A; Hildebrand, John G

    2009-02-24

    For animals to execute odor-driven behaviors, the olfactory system must process complex odor signals and maintain stimulus identity in the face of constantly changing odor intensities [1-5]. Surprisingly, how the olfactory system maintains identity of complex odors is unclear [6-10]. We took advantage of the plant-pollinator relationship between the Sacred Datura (Datura wrightii) and the moth Manduca sexta[11, 12] to determine how olfactory networks in this insect's brain represent odor mixtures. We combined gas chromatography and neural-ensemble recording in the moth's antennal lobe to examine population codes for the floral mixture and its fractionated components. Although the floral scent of D. wrightii comprises at least 60 compounds, only nine of those elicited robust neural responses. Behavioral experiments confirmed that these nine odorants mediate flower-foraging behaviors, but only as a mixture. Moreover, the mixture evoked equivalent foraging behaviors over a 1000-fold range in dilution, suggesting a singular percept across this concentration range. Furthermore, neural-ensemble recordings in the moth's antennal lobe revealed that reliable encoding of the floral mixture is organized through synchronized activity distributed across a population of glomerular coding units, and this timing mechanism may bind the features of a complex stimulus into a coherent odor percept. PMID:19230669

  20. Smelling shapes: crossmodal correspondences between odors and shapes.

    PubMed

    Hanson-Vaux, Grant; Crisinel, Anne-Sylvie; Spence, Charles

    2013-02-01

    Crossmodal correspondences between odors and visual stimuli-particularly colors-are well-established in the literature, but there is a paucity of research involving visual shape correspondences. Crossmodal associations between 20 odors (a selection of those commonly found in wine) and visual shape stimuli ("kiki"/"bouba" forms-Köhler W. 1929. Gestalt psychology. New York: Liveright.) were investigated in a sample of 25 participants (mean age of 21 years). The odors were rated along a form scale anchored by 2 shapes, as well as several descriptive adjective scales. Two of the odors were found to be significantly associated with an angular shape (lemon and pepper) and two others with a rounded shape (raspberry and vanilla). Principal component analysis indicated that the hedonic value and intensity of odors are important in this crossmodal association, with more unpleasant and intense smells associated with more angular forms. These results are discussed in terms of their practical applications, such as in the use of bottle, logo, or label shape by marketers of perfume and wine to convey the prominent notes through congruent odor-shape pairing. In conclusion, these results support the existence of widespread crossmodal associations (or correspondences) between odors and visual shape stimuli. PMID:23118203

  1. Behavioral reactions to novel food odors by intertidal hermit crabs.

    PubMed

    Tran, Mark V

    2015-04-01

    Novel food items represent important food resources for generalist scavengers, such as intertidal hermit crabs. For animals that rely heavily on olfaction to mediate foraging, their first encounters with novel food items come from the detection of novel food odors. Although crustaceans have been shown to possess sensory mechanisms for processing novel odors, little is known about the level of stimulus reinforcement needed to maintain behavioral responses to novel food odors upon subsequent exposures. In the context of foraging, reinforcement of a novel food odor comes from feeding on the novel food item after sensory detection of the food item. This study tested the behavioral responses of hermit crabs to a novel food odor over repeated exposures both with and without stimulus reinforcement. The results show that stimulus reinforcement is needed for the animals to maintain their baseline level of behavioral responses to the novel food odors. Animals that were allowed to feed on the novel food item after first exposure (reinforced treatment) maintained strong behavioral reactions to the novel food odor during subsequent exposures. The behavioral reactions of animals that were not allowed to feed on the novel food item after first exposure (unreinforced treatment) rapidly declined. PMID:25562193

  2. Predator odor fear conditioning: Current perspectives and new directions

    PubMed Central

    Takahashi, Lorey K.; Chan, Megan M.; Pilar, Mark L.

    2008-01-01

    Predator odor fear conditioning involves the use of a natural unconditioned stimulus, as opposed to aversive electric foot-shock, to obtain novel information on the neural circuitry associated with emotional learning and memory. Researchers are beginning to identify brain sites associated with conditioned contextual fear such as the ventral anterior olfactory nucleus, dorsal premammillary nucleus, ventrolateral periaqueductal gray, cuneiform nucleus, and locus coeruleus. In addition, a few studies have reported an involvement of the basolateral and medial nucleus of the amygdala and hippocampus in fear conditioning. However, several important issues concerning the effectiveness of different predator odor unconditioned stimuli to produce fear conditioning, the precise role of brain nuclei in fear conditioning, and the general relation between the current predator odor and the traditional electric foot-shock fear conditioning procedures remain to be satisfactorily addressed. This review discusses the major behavioral results in the current predator odor fear conditioning literature and introduces two novel contextual and auditory fear conditioning models using cat odor. The new models provide critical information on the acquisition of conditioned fear behavior during training and the expression of conditioned responses in the retention test. Future studies adopting fear conditioning procedures that incorporate measures of both unconditioned and conditioned responses during training may lead to broad insights into predator odor fear conditioning and identify specific brain nuclei mediating conditioned stimulus – predator odor unconditioned stimulus associations. PMID:18577397

  3. Crossmodal correspondences between odors and contingent features: odors, musical notes, and geometrical shapes.

    PubMed

    Deroy, Ophelia; Crisinel, Anne-Sylvie; Spence, Charles

    2013-10-01

    Olfactory experiences represent a domain that is particularly rich in crossmodal associations. Whereas associations between odors and tastes, or other properties of their typical sources such as color or temperature, can be straightforwardly explained by associative learning, other matchings are much harder to explain in these terms, yet surprisingly are shared across individuals: The majority of people, for instance, associate certain odors and auditory features, such as pitch (Belkin, Martin, Kemp, & Gilbert, Psychological Science 8:340-342, 1997; Crisinel & Spence, Chemical Senses 37:151-158, 2012b) or geometrical shapes (Hanson-Vaux, Crisinel, & Spence, Chemical Senses 38:161-166, 2013; Seo, Arshamian, et al., Neuroscience Letters 478:175-178, 2010). If certain odors might indeed have been encountered while listening to certain pieces of music or seeing certain geometrical shapes, these encounters are very unlikely to have been statistically more relevant than others; for this reason, associative learning from regular exposure is ruled out, and thus alternative explanations in terms of metaphorical mappings are usually defended. Here we argue that these associations are not primarily conceptual or linguistic, but are grounded in structural perceptual or neurological determinants. These cases of crossmodal correspondences established between contingent environmental features can be explained as amodal, indirect, and transitive mappings across modalities. Surprising associations between odors and contingent sensory features can be investigated as genuine cases of crossmodal correspondences, akin to other widespread cases of functional correspondences that hold, for instance, between auditory and visual features, and can help reveal the structural determinants weighing on the acquisition of these crossmodal associations. PMID:23463615

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

    PubMed

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

    2012-03-01

    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. PMID:22155966

  5. Fast Odor Learning Improves Reliability of Odor Responses in the Locust Antennal Lobe

    PubMed Central

    Bazhenov, Maxim; Stopfer, Mark; Sejnowski, Terrence J.; Laurent, Gilles

    2010-01-01

    Summary Recordings in the locust antennal lobe (AL) reveal activity-dependent, stimulus-specific changes in projection neuron (PN) and local neuron response patterns over repeated odor trials. During the first few trials, PN response intensity decreases, while spike time precision increases, and coherent oscillations, absent at first, quickly emerge. We examined this “fast odor learning” with a realistic computational model of the AL. Activity-dependent facilitation of AL inhibitory synapses was sufficient to simulate physiological recordings of fast learning. In addition, in experiments with noisy inputs, a network including synaptic facilitation of both inhibition and excitation responded with reliable spatiotemporal patterns from trial to trial despite the noise. A network lacking fast plasticity, however, responded with patterns that varied across trials, reflecting the input variability. Thus, our study suggests that fast olfactory learning results from stimulus-specific, activity-dependent synaptic facilitation and may improve the signal-to-noise ratio for repeatedly encountered odor stimuli. PMID:15882647

  6. Odors enhance the salience of matching images during the attentional blink

    PubMed Central

    Robinson, Amanda K.; Mattingley, Jason B.; Reinhard, Judith

    2013-01-01

    As any food critic knows, the visual presentation of a dish can enhance its aroma. Is the reverse also true? Here we investigated whether odors can enhance the salience of familiar visual objects at the limits of perceptual discrimination, using rapid serial visual presentations (RSVP) to induce an attentional blink (AB). We had participants view RSVP streams containing photographs of odor-related objects (lemon, orange, rose, and mint) amongst non-odor related distractors. In each trial, participants inhaled a single odor, which either matched the odor-related target within the stream (congruent trials), did not match the odor-related target (incongruent trials), or was irrelevant with respect to the target. Congruent odors significantly attenuated the AB for odor-related visual targets, compared with incongruent and irrelevant odors. The findings suggest that familiar odors can render matching visual objects more salient, thereby enhancing their competitive strength at the limits of temporal attention. PMID:24223539

  7. Study of Odor Approximation by Using Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Ohno, Masashi; Nihei, Yasunori; Nakamoto, Takamichi

    2011-09-01

    Since a set of odor components to cover wide range of smells has not been revealed yet, we studied the selection of odor components using essential-oil mass spectrum database. Basis vectors were extracted using non-negative matrix factorization method1 and then non-negative least squares method was used to determine the recipe. The odor approximations of three typical essential oils were confirmed by the sensory test. It was found that the mass spectrum data were correlated with the sensory test result. Moreover, this correlation was remarkable in the high m/z region.

  8. Odor and the Clean Air Act

    SciTech Connect

    Morse, H.N.

    1993-01-01

    The case described in this paper involves the interpretation of language contained in the Texas Clean Air Act Texas Health and Safety Code Ann. Sections 382.001-382.141. The State of Texas, on behalf of the Texas Air Control Board, brought suit in the District Court of Erath County, Texas against the F/R Cattle Company, Inc., alleging that, because of odors emanating from the company's cattle feeding facility, the company was violating the Clean Air Act. The Board is granted the power and duty to administer the Clean Air Act and is directed to accomplish the purposes of the Act through the control of air contaminants by all practical and economically feasible methods. Described here is the evidence presented at and proceedings of the trial.

  9. Odorant-binding proteins in insects.

    PubMed

    Zhou, Jing-Jiang

    2010-01-01

    Our understanding of the molecular and biochemical mechanisms that mediate chemoreception in insects has been greatly improved after the discovery of olfactory and taste receptor proteins. However, after 50 years of the discovery of first insect sex pheromone from the silkmoth Bombyx mori, it is still unclear how hydrophobic compounds reach the dendrites of sensory neurons in vivo across aqueous space and interact with the sensory receptors. The presence of soluble polypeptides in high concentration in the lymph of chemosensilla still poses unanswered questions. More than two decades after their discovery and despite the wealth of structural and biochemical information available, the physiological function of odorant-binding proteins (OBPs) is not well understood. Here, I review the structural properties of different subclasses of insect OBPs and their binding to pheromones and other small ligands. Finally, I discuss current ideas and models on the role of such proteins in insect chemoreception. PMID:20831949

  10. The Swipe Card Model of Odorant Recognition

    PubMed Central

    Brookes, Jennifer C.; Horsfield, Andrew P.; Stoneham, A. Marshall

    2012-01-01

    Just how we discriminate between the different odours we encounter is not completely understood yet. While obviously a matter involving biology, the core issue is a matter for physics: what microscopic interactions enable the receptors in our noses-small protein switches—to distinguish scent molecules? We survey what is and is not known about the physical processes that take place when we smell things, highlighting the difficulties in developing a full understanding of the mechanics of odorant recognition. The main current theories, discussed here, fall into two major groups. One class emphasises the scent molecule's shape, and is described informally as a “lock and key” mechanism. But there is another category, which we focus on and which we call “swipe card” theories: the molecular shape must be good enough, but the information that identifies the smell involves other factors. One clearly-defined “swipe card” mechanism that we discuss here is Turin's theory, in which inelastic electron tunnelling is used to discern olfactant vibration frequencies. This theory is explicitly quantal, since it requires the molecular vibrations to take in or give out energy only in discrete quanta. These ideas lead to obvious experimental tests and challenges. We describe the current theory in a form that takes into account molecular shape as well as olfactant vibrations. It emerges that this theory can explain many observations hard to reconcile in other ways. There are still some important gaps in a comprehensive physics-based description of the central steps in odorant recognition. We also discuss how far these ideas carry over to analogous processes involving other small biomolecules, like hormones, steroids and neurotransmitters. We conclude with a discussion of possible quantum behaviours in biology more generally, the case of olfaction being just one example. This paper is presented in honour of Prof. Marshall Stoneham who passed away unexpectedly during its

  11. The swipe card model of odorant recognition.

    PubMed

    Brookes, Jennifer C; Horsfield, Andrew P; Stoneham, A Marshall

    2012-01-01

    Just how we discriminate between the different odours we encounter is not completely understood yet. While obviously a matter involving biology, the core issue isa matter for physics: what microscopic interactions enable the receptors in our noses-small protein switches—to distinguish scent molecules? We survey what is and is not known about the physical processes that take place when we smell things, highlighting the difficulties in developing a full understanding of the mechanics of odorant recognition. The main current theories, discussed here, fall into two major groups. One class emphasises the scent molecule's shape, and is described informally as a "lock and key" mechanism. But there is another category, which we focus on and which we call "swipe card" theories:the molecular shape must be good enough, but the information that identifies the smell involves other factors. One clearly-defined "swipe card" mechanism that we discuss here is Turin's theory, in which inelastic electron tunnelling is used to discern olfactant vibration frequencies. This theory is explicitly quantal, since it requires the molecular vibrations to take in or give out energy only in discrete quanta. These ideas lead to obvious experimental tests and challenges. We describe the current theory in a form that takes into account molecular shape as well as olfactant vibrations. It emerges that this theory can explain many observations hard to reconcile in other ways. There are still some important gaps in a comprehensive physics-based description of the central steps in odorant recognition. We also discuss how far these ideas carry over to analogous processes involving other small biomolecules, like hormones, steroids and neurotransmitters. We conclude with a discussion of possible quantum behaviours in biology more generally, the case of olfaction being just one example. This paper is presented in honour of Prof. Marshall Stoneham who passed away unexpectedly during its writing. PMID

  12. Foods - fresh vs. frozen or canned

    MedlinePlus

    Frozen foods vs. fresh or canned; Fresh foods vs. frozen or canned; Frozen vegetables versus fresh ... a well-balanced diet. Many people wonder if frozen and canned vegetables are as healthy for you ...

  13. An electroolfactogram study of odor response patterns from the mouse olfactory epithelium with reference to receptor zones and odor sorptiveness.

    PubMed

    Coppola, D M; Waggener, C T; Radwani, S M; Brooks, D A

    2013-04-01

    Olfactory sensory neuron (OSN) responses to odors, measured at the population level, tend to be spatially heterogeneous in the vertebrates that have been studied. These response patterns vary between odors but are similar across subjects for a given stimulus. However, few species have been studied making functional interpretation of these patterns problematic. One proximate explanation for the spatial heterogeneity of odor responses comes from evidence that olfactory receptor (OR) genes in rodents are expressed in OSN populations that are spatially restricted to a few zones in the olfactory epithelium (OE). A long-standing functional explanation for response anisotropy in the OE posits that it is the signature of a supplementary mechanism for quality coding, based on the sorptive properties of odor molecules. These theories are difficult to assess because most mapping studies have utilized few odors, provided little replication, or involved but a single species (rat). In fact, to our knowledge, a detailed olfactory response "map" has not been reported for mouse, the species used in most studies of gene localization. Here we report the results of a study of mouse OE response patterns using the electroolfactogram (EOG). We focused on the medial aspect of olfactory turbinates that are accessible in the midsagittal section. This limited approach still allowed us to test predictions derived from the zonal distribution of OSN types and the sorption hypothesis. In 3 separate experiments, 290 mice were used to record EOGs from a set of standard locations along each of 4 endoturbinates utilizing 11 different odors resulting in over 4,400 separate recordings. Our results confirmed a marked spatial heterogeneity in odor responses that varied with odor, as seen in other species. However, no discontinuities were found in the odor-specific response patterns across the OE as might have been predicted given the existence of classical receptor zones nor did we find clear support

  14. Pattern recognition for selective odor detection with gas sensor arrays.

    PubMed

    Kim, Eungyeong; Lee, Seok; Kim, Jae Hun; Kim, Chulki; Byun, Young Tae; Kim, Hyung Seok; Lee, Taikjin

    2012-01-01

    This paper presents a new pattern recognition approach for enhancing the selectivity of gas sensor arrays for clustering intelligent odor detection. The aim of this approach was to accurately classify an odor using pattern recognition in order to enhance the selectivity of gas sensor arrays. This was achieved using an odor monitoring system with a newly developed neural-genetic classification algorithm (NGCA). The system shows the enhancement in the sensitivity of the detected gas. Experiments showed that the proposed NGCA delivered better performance than the previous genetic algorithm (GA) and artificial neural networks (ANN) methods. We also used PCA for data visualization. Our proposed system can enhance the reproducibility, reliability, and selectivity of odor sensor output, so it is expected to be applicable to diverse environmental problems including air pollution, and monitor the air quality of clean-air required buildings such as a kindergartens and hospitals. PMID:23443378

  15. Frequency transitions in odor-evoked neural oscillations

    PubMed Central

    Ito, Iori; Bazhenov, Maxim; Ong, Rose Chik-ying; Raman, Baranidharan; Stopfer, Mark

    2009-01-01

    Summary In many species sensory stimuli elicit the oscillatory synchronization of groups of neurons. What determines the properties of these oscillations? In the olfactory system of the moth we found that odors elicited oscillatory synchronization through a neural mechanism like that described in locust and Drosophila. During responses to long odor pulses, oscillations suddenly slowed as net olfactory receptor neuron (ORN) output decreased; thus, stimulus intensity appeared to determine oscillation frequency. However, changing the concentration of the odor had little effect upon oscillatory frequency. Our recordings in vivo and computational models based on these results suggested the main effect of increasing odor concentration was to recruit additional, less well-tuned ORNs whose firing rates were tightly constrained by adaptation and saturation. Thus, in the periphery, concentration is encoded mainly by the size of the responsive ORN population, and oscillation frequency is set by the adaptation and saturation of this response. PMID:20005825

  16. Evaluation Of Odors Associated With Land Application Of Biosolids

    EPA Science Inventory

    An odor study was performed at a biosolids application demonstration site using several different gas collection devices and analytical methods to determine changes in air concentration of several organic and inorganic compounds associated with biosolids application over various ...

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

    NASA Astrophysics Data System (ADS)

    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.

  18. Pattern Recognition for Selective Odor Detection with Gas Sensor Arrays

    PubMed Central

    Kim, Eungyeong; Lee, Seok; Kim, Jae Hun; Kim, Chulki; Byun, Young Tae; Kim, Hyung Seok; Lee, Taikjin

    2012-01-01

    This paper presents a new pattern recognition approach for enhancing the selectivity of gas sensor arrays for clustering intelligent odor detection. The aim of this approach was to accurately classify an odor using pattern recognition in order to enhance the selectivity of gas sensor arrays. This was achieved using an odor monitoring system with a newly developed neural-genetic classification algorithm (NGCA). The system shows the enhancement in the sensitivity of the detected gas. Experiments showed that the proposed NGCA delivered better performance than the previous genetic algorithm (GA) and artificial neural networks (ANN) methods. We also used PCA for data visualization. Our proposed system can enhance the reproducibility, reliability, and selectivity of odor sensor output, so it is expected to be applicable to diverse environmental problems including air pollution, and monitor the air quality of clean-air required buildings such as a kindergartens and hospitals. PMID:23443378

  19. Relationship between odor perception and depression in the Japanese elderly.

    PubMed

    Satoh, S; Morita, N; Matsuzaki, I; Konishi, T; Nakano, T; Minoshita, S; Arizono, H; Saito, S; Ayabe, A S

    1996-10-01

    Odor perception has been studied in patients with various mental disorders; however, no consensus has been reached as to its detection, identification, or pleasantness/unpleasantness of odors especially in patients with depression. One hundred and nineteen normal elderly individuals living at home were exposed to odors of rose, perfume, white ginger, Indian ink, cigarette smoke, milk, feces and orange scent using the scratch and sniff method. They were asked to rate the strength of each odor, its pleasantness or unpleasantness, their liking for it, and their familiarity with it. They were also asked to complete a self-rating depression scale (SDS). The relationship of the score of each psychological olfactory scale with the SDS score and the difference in the score of each psychological scale between high-SDS and low-SDS groups are discussed. PMID:9201790

  20. ODOR AND IRRITATION EFFECTS OF A VOLATILE ORGANIC COMPOUND MIXTURE

    EPA Science Inventory

    Human exposure to volatile organic compounds elicits a variety ofsymptoms, many of which are thought to be mediated by the olfactoryand trigeminal systems. his report describes evidence indicatingthat perceived odor intensity diminishes during prolonged exposure,whearas irritatin...

  1. Individual odor differences and their social functions in insects.

    PubMed

    Barrows, E M; Bell, W J; Michener, C D

    1975-07-01

    The evolution of individual or subgroup differences in odors of halictine bees is suggested from possible widespread intraspecific variation in pheromones. An important result of such variation may be maintenance of genetic polymorphisms; in nesting Hymenoptera odor differences may also facilitate individual nest recognition. In Lasioglosum zephyrum males habituate to odors of different females and perhaps thus save time by not trying to copulate with nonreceptive individuals. Guards (females) at nest entrances distinguish their few nestmates (other females) from other conspecific individuals by odors, seemingly pheromones. Duration of the habituation in L. zephyrum is at least an hour (perhaps much more) for males in relation to females and 6 or 7 days for guards in relation to nestmates. Studies of pheromones should take into consideration the possibility of pheromonal polymorphism in any species and the likelihood that it may be significant from biological and practical viewpoints. PMID:1058498

  2. Synaptic clusters function as odor operators in the olfactory bulb

    PubMed Central

    Migliore, Michele; Cavarretta, Francesco; Marasco, Addolorata; Tulumello, Eleonora; Hines, Michael L.; Shepherd, Gordon M.

    2015-01-01

    How the olfactory bulb organizes and processes odor inputs through fundamental operations of its microcircuits is largely unknown. To gain new insight we focus on odor-activated synaptic clusters related to individual glomeruli, which we call glomerular units. Using a 3D model of mitral and granule cell interactions supported by experimental findings, combined with a matrix-based representation of glomerular operations, we identify the mechanisms for forming one or more glomerular units in response to a given odor, how and to what extent the glomerular units interfere or interact with each other during learning, their computational role within the olfactory bulb microcircuit, and how their actions can be formalized into a theoretical framework in which the olfactory bulb can be considered to contain “odor operators” unique to each individual. The results provide new and specific theoretical and experimentally testable predictions. PMID:26100895

  3. Avoidance of nonhost plants by a bark beetle, Pityogenes bidentatus, in a forest of odors

    NASA Astrophysics Data System (ADS)

    Byers, John A.; Zhang, Qing-He; Birgersson, Göran

    The bark beetle, Pityogenes bidentatus (Coleoptera: Scolytidae), searches in mixed conifer and deciduous forests of northern Europe for suitable branches of its host, Scots pine (Pinus sylvestris). We tested whether odors from several diverse nonhost trees and plants common in the habitat (e.g., mountain ash, Sorbus aucuparia; oak, Quercus robur; alder buckthorn, Frangula alnus; blueberry, Vaccinium myrtillus; raspberry, Rubus idaeus; and grass, Deschampsia flexuosa) would reduce the attraction of the bark beetle to traps releasing its aggregation pheromone components in the field. Volatiles from the leaves or bark of each of these plants significantly reduced the attraction of the beetles to their pheromone. Odors collected from these nonhosts and analyzed by GC/MS contained monoterpenes, sesquiterpenes, and ``green-leaf'' alcohols, several of which (e.g., 1-octene-3-ol and β-caryophyllene) reduced the attraction to pheromone in the field and elicited electroantennographic responses. In the laboratory, reproduction by the beetle was marginal in nonhost Norway spruce, Picea abies, and was absent in the other nonhost trees. Olfactory avoidance of unsuitable nonhosts may have evolved due to advantages in avoiding mistakes during host selection.

  4. Supernumerary Formation of Olfactory Glomeruli Induced by Chronic Odorant Exposure: A Constructivist Expression of Neural Plasticity

    PubMed Central

    Valle-Leija, Pablo; Blanco-Hernández, Eduardo; Drucker-Colín, Rene; Gutiérrez-Ospina, Gabriel; Vidaltamayo, Roman

    2012-01-01

    It is accepted that sensory experience instructs the remodelling of neuronal circuits during postnatal development, after their specification has occurred. The story is less clear with regard to the role of experience during the initial formation of neuronal circuits, whether prenatal or postnatal, since this process is now supposed to be primarily influenced by genetic determinants and spontaneous neuronal firing. Here we evaluated this last issue by examining the effect that postnatal chronic exposure to cognate odorants has on the formation of I7 and M72 glomeruli, iterated olfactory circuits that are formed before and after birth, respectively. We took advantage of double knock-in mice whose I7 and M72 primary afferents express green fluorescent protein and β-galactosidase, correspondingly. Our results revealed that postnatal odorant chronic exposure led to the formation of permanent supernumerary I7 and M72 glomeruli in a dose and time dependent manner. Glomeruli in exposed mice were formed within the same regions of olfactory bulb and occupy small space volumes compared to the corresponding single circuits in non-exposed mice. We suggest that local reorganization of the primary afferents could participate in the process of formation of supernumerary glomeruli. Overall, our results support that sensory experience indeed instructs the permanent formation of specific glomeruli in the mouse olfactory bulb by means of constructivist processes. PMID:22511987

  5. Simultaneous removal of multiple odorants from source water suffering from septic and musty odors: Verification in a full-scale water treatment plant with ozonation.

    PubMed

    Guo, Qingyuan; Yang, Kai; Yu, Jianwei; Wang, Chunmiao; Wen, Xiaodong; Zhang, Liping; Yang, Min; Xia, Ping; Zhang, Dong

    2016-09-01

    Ozonation is known to be very effective in the removal of odorants from source water. However, it is not known if ozonation is effective in the removal of multiple odorants causing different types of odors. In this study, the removal performance for odors and odorants were evaluated in a Water Treatment Plant (WTP), which was equipped with coagulation, sedimentation, ozonation, biological activated carbon (BAC) filtration, sand filtration, and chlorination in succession and located in the downstream of the Huangpu (HP) River, over the period from April, 2014 to April, 2015. Flavor profile analysis (FPA) results showed that the source water was constantly associated with septic and musty odors. Geosmin and 2-MIB, with an average OAV of 4.54 and 1.38, respectively, were the major odorants for musty odor, while bis(2-chloroisopropyl) ether, DEDS and DMDS with an average OAV of 2.35, 1.65 and 0.78, respectively, might be responsible for the septic odor. While the musty odor could be removed effectively through the combination of ozonation and BAC, the septic odor and associated odorants required further treatment with sand filtration and chlorination for complete removal. It is clear that the advanced treatment process was effective for the treatment of source water containing complicated odorants. It should be noted that the sedimentation process needs careful management because release of odorants may occur during the treatment. The result of this study will be helpful for the mitigation of odors in WTP using source waters suffering from complicated odor problems. PMID:27173729

  6. Odor and irritation effects of a volatile organic compound mixture

    SciTech Connect

    Hudnell, H.K.; Otto, O.D.; Mohave, L.; House, D.E.

    1990-01-01

    Human exposure to volatile organic compounds elicits a variety of symptoms, many of which are thought to be mediated by the olfactory and trigeminal systems. The report describes evidence indicating that perceived odor intensity diminishes during prolonged exposure, whereas irritation of the eyes and throat reaches an asymptotic level. Both odor and irritation appear to influence the assessment of air quality. Results of the study will be used in designing future indoor air studies related to sick building syndrome.

  7. Wild Western Lowland Gorillas Signal Selectively Using Odor

    PubMed Central

    Klailova, Michelle; Lee, Phyllis C.

    2014-01-01

    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. PMID:25006973

  8. Wild western lowland gorillas signal selectively using odor.

    PubMed

    Klailova, Michelle; Lee, Phyllis C

    2014-01-01

    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. PMID:25006973

  9. Odorant-sensitive phospholipase C in insect antennae.

    PubMed

    Boekhoff, I; Strotmann, J; Raming, K; Tareilus, E; Breer, H

    1990-01-01

    Exogenous tritiated phosphatidylinositol bisphosphate added to antennal preparations from locust and cockroach was hydrolysed releasing inositol trisphosphate. High activity of phospholipase C was detected in the soluble as well as in the membrane fraction. At low free calcium concentrations hydrolysis of the labelled lipid was stimulated by odorants and pheromones in a GTP-dependent manner. Consequently the level of inositol trisphosphate in antennal preparations increased upon odorant stimulation. PMID:2176800

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

    PubMed Central

    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

  11. Pleasant and Unpleasant Odors Influence Hedonic Evaluations of Human Faces: An Event-Related Potential Study

    PubMed Central

    Cook, Stephanie; Fallon, Nicholas; Wright, Hazel; Thomas, Anna; Giesbrecht, Timo; Field, Matt; Stancak, Andrej

    2015-01-01

    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 3 s 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. PMID:26733843

  12. Pleasant and Unpleasant Odors Influence Hedonic Evaluations of Human Faces: An Event-Related Potential Study.

    PubMed

    Cook, Stephanie; Fallon, Nicholas; Wright, Hazel; Thomas, Anna; Giesbrecht, Timo; Field, Matt; Stancak, Andrej

    2015-01-01

    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 3 s 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. PMID:26733843

  13. Green Architecture

    NASA Astrophysics Data System (ADS)

    Lee, Seung-Ho

    Today, the environment has become a main subject in lots of science disciplines and the industrial development due to the global warming. This paper presents the analysis of the tendency of Green Architecture in France on the threes axes: Regulations and Approach for the Sustainable Architecture (Certificate and Standard), Renewable Materials (Green Materials) and Strategies (Equipments) of Sustainable Technology. The definition of 'Green Architecture' will be cited in the introduction and the question of the interdisciplinary for the technological development in 'Green Architecture' will be raised up in the conclusion.

  14. Post-thaw bovine spermatozoal quality estimated from fresh samples.

    PubMed

    Thomas, C A; Garner, D L

    1994-01-01

    Comparisons were made among flow cytometrically quantified populations of fresh and cryopreserved bovine spermatozoa, tri-stained with fluorophores rhodamine 123 (R123), 5- (and 6-) carboxy-4',5'-dimethylfluorescein diacetate (CMFDA), and propidium iodide (PI), and analyzed by dual parameter flow cytometry. The purpose was to find parameters in fresh semen samples that were potentially predictive of frozen sample parameters so that bulls with marginal cryopreservation capacity could be identified. Fresh and cryopreserved aliquots of semen from two sets of six bulls were semen processed in either milk (bulls 1-6) or egg yolk citrate (bulls 11-16). Membrane-damaged red (PI) and intact green (CMFDA + R123) populations were evaluated as percentages of 10,000-cell samples or numbers per straw. In milk, gated central subsets of membrane-damaged sperm cells in fresh samples and moribund cells in post-thaw samples were significantly correlated for sample percentages (r = 0.90, P = 0.014) and cell numbers per straw (r = 0.94, P = 0.006). In egg yolk citrate, fresh and frozen membrane-damaged populations were correlated (percentages: r = 0.81, P = 0.048; numbers: r = 0.88, P = 0.019). Additionally, post-thaw motility estimated by a photographic method was correlated with the number of sperm cells per straw in the intact central green subset (r = 0.98, P = 0.0006). These findings suggest that partitioning red and gree populations into smaller, central subset populations reveals significant relationships between fresh and cryopreserved bull ejaculates. The proportion of membrane-damaged spermatozoa in fresh semen seems to be predictive of the proportion of post-thaw membrane-damaged or moribund spermatozoa. The data consistently showed ejaculates of bulls 1 and 12 as having the greatest cryopreservation potentials, and bulls 4 and 16 the least. Thus, flow cytometric evaluation of fresh semen may be useful for identifying young sires with relatively poor fertilizing potential

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

    PubMed

    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. PMID:26191021

  16. Serial position effects in recognition memory for odors.

    PubMed

    Reed, P

    2000-03-01

    Five experiments examined recognition memory for sequentially presented odors. Participants were presented with a sequence of odors and then had to identify an odor from the list in a test probe containing 2 odors. All experiments demonstrated enhanced recognition of odors presented at the start and end of a series, compared with those presented in the middle of the series when a 3-s retention interval between list termination and test was used. In Experiments 2 and 3, when a 30-s or 60-s retention interval was used, participants performed at slightly lower levels, although the serial position function was similar to that obtained with the 3-s retention interval. These results were noted with a 5-item (Experiments 1 and 4), 7-item (Experiment 2), 6-item (Experiment 3), and 4-item (Experiment 5) list of odors. As the number of test trials increased, recognition performance decreased, indicating a strong role for olfactory fatigue or interference in these procedures. A verbal suppression task, used in Experiments 4 and 5, had little influence on serial-position-based performance. PMID:10764103

  17. Quality assured measurements of animal building emissions: odor concentrations.

    PubMed

    Jacobson, Larry D; Hetchler, Brian P; Schmidt, David R; Nicolai, Richard E; Heber, Albert J; Ni, Ji-Qin; Hoff, Steven J; Koziel, Jacek A; Zhang, Yuanhui; Beasley, David B; Parker, David B

    2008-06-01

    Standard protocols for sampling and measuring odor emissions from livestock buildings are needed to guide scientists, consultants, regulators, and policy-makers. A federally funded, multistate project has conducted field studies in six states to measure emissions of odor, coarse particulate matter (PM(10)), total suspended particulates, hydrogen sulfide, ammonia, and carbon dioxide from swine and poultry production buildings. The focus of this paper is on the intermittent measurement of odor concentrations at nearly identical pairs of buildings in each state and on protocols to minimize variations in these measurements. Air was collected from pig and poultry barns in small (10 L) Tedlar bags through a gas sampling system located in an instrument trailer housing gas and dust analyzers. The samples were analyzed within 30 hr by a dynamic dilution forced-choice olfactometer (a dilution apparatus). The olfactometers (AC'SCENT International Olfactometer, St. Croix Sensory, Inc.) used by all participating laboratories meet the olfactometry standards (American Society for Testing and Materials and European Committee for Standardization [CEN]) in the United States and Europe. Trained panelists (four to eight) at each laboratory measured odor concentrations (dilution to thresholds [DT]) from the bag samples. Odor emissions were calculated by multiplying odor concentration differences between inlet and outlet air by standardized (20 degrees C and 1 atm) building airflow rates. PMID:18581810

  18. Nest odor dynamics in the social wasp Vespula vulgaris

    NASA Astrophysics Data System (ADS)

    Steinmetz, Inge; Schmolz, Erik

    2005-09-01

    We investigated nest odor dynamics in the common yellow jacket, Vespula vulgaris. In six isolated colonies, we tested the aggression rates toward dead nestmates that had been stored for 10 min, 10 and 19 days outside their colonies at 76 °C. The aggression rate increased from about 12% toward recently killed nestmates up to 30% toward nestmates killed 19 days before the experiment. Obviously, the conserved nest odor profile of the nestmates frozen for several days did not match with that of their colony anymore. This indicates a change of the nest odor within the colony. In a second experiment, we kept two colonies each in one nest box with a complete separation of both neighbor nests by a solid wall inside the box for 28 days. In confrontation experiments, the colony members treated dead foragers from the neighbor nest as aggressively as dead foreign, non-neighbor workers (about 39% each) whereas only about 14% reacted aggressively toward dead nestmates. Seventeen days after the replacement of the solid wall by a metallic grid, which allowed no physical contact but air exchange between the two neighbor colonies, the aggression rates toward foreign workers and nestmates remained relatively unaffected whereas it decreased significantly toward dead neighbors to about 11%. These results suggest a nest odor dynamic caused by volatiles transferred between two adjacent colonies, resulting in an equalization of the former colony specific nest odors. A change of nest odor dynamics influenced by volatiles was so far described only for one ant species at all.

  19. Chemotopic Odorant Coding in a Mammalian Olfactory System

    PubMed Central

    Johnson, Brett A.; Leon, Michael

    2008-01-01

    Systematic mapping studies involving 365 odorant chemicals have shown that glomerular responses in the rat olfactory bulb are organized spatially in patterns that are related to the chemistry of the odorant stimuli. This organization involves the spatial clustering of principal responses to numerous odorants that share key aspects of chemistry such as functional groups, hydrocarbon structural elements, and/or overall molecular properties related to water solubility. In several of the clusters, responses shift progressively in position according to odorant carbon chain length. These response domains appear to be constructed from orderly projections of sensory neurons in the olfactory epithelium and may also involve chromatography across the nasal mucosa. The spatial clustering of glomerular responses may serve to “tune” the principal responses of bulbar projection neurons by way of inhibitory interneuronal networks, allowing the projection neurons to respond to a narrower range of stimuli than their associated sensory neurons. When glomerular activity patterns are viewed relative to the overall level of glomerular activation, the patterns accurately predict the perception of odor quality, thereby supporting the notion that spatial patterns of activity are the key factors underlying that aspect of the olfactory code. A critical analysis suggests that alternative coding mechanisms for odor quality, such as those based on temporal patterns of responses, enjoy little experimental support. PMID:17480025

  20. Differential Electrophysiological Responses to Odorant Isotopologues in Drosophilid Antennae123

    PubMed Central

    Drimyli, Efstathia; Gaitanidis, Alexandros; Maniati, Klio; Turin, Luca

    2016-01-01

    Abstract Olfaction presents the ultimate challenge to molecular recognition as thousands of molecules have to be recognized by far fewer olfactory receptors. We have presented evidence that Drosophila readily distinguish odorants based on their molecular vibrations using a battery of behavioral assays suggesting engagement of a molecular vibration-sensing component. Here we interrogate electrophysiologically the antennae of four Drosophilids and demonstrate conserved differential response amplitudes to aldehydes, alcohols, ketones, nitriles, and their deuterated isotopologues. Certain deuterated odorants evoked larger electroantennogram (EAG) amplitudes, while the response to the normal odorant was elevated in others. Significantly, benzonitrile isotopologues were not distinguishable as predicted. This suggests that isotopologue-specific EAG amplitudes result from differential activation of specific olfactory receptors. In support of this, odorants with as few as two deuteria evoke distinct EAG amplitudes from their normal isotopologues, and this is independent of the size of the deuterated molecule. Importantly, we find no evidence that these isotopologue-specific amplitudes depend on perireceptor mechanisms or other pertinent physical property of the deuterated odorants. Rather, our results strongly suggest that Drosophilid olfactory receptors are activated by molecular vibrations differentiating similarly sized and shaped odorants in vivo, yielding sufficient differential information to drive behavioral choices. PMID:27351023

  1. Differential Electrophysiological Responses to Odorant Isotopologues in Drosophilid Antennae.

    PubMed

    Drimyli, Efstathia; Gaitanidis, Alexandros; Maniati, Klio; Turin, Luca; Skoulakis, Efthimios M C

    2016-01-01

    Olfaction presents the ultimate challenge to molecular recognition as thousands of molecules have to be recognized by far fewer olfactory receptors. We have presented evidence that Drosophila readily distinguish odorants based on their molecular vibrations using a battery of behavioral assays suggesting engagement of a molecular vibration-sensing component. Here we interrogate electrophysiologically the antennae of four Drosophilids and demonstrate conserved differential response amplitudes to aldehydes, alcohols, ketones, nitriles, and their deuterated isotopologues. Certain deuterated odorants evoked larger electroantennogram (EAG) amplitudes, while the response to the normal odorant was elevated in others. Significantly, benzonitrile isotopologues were not distinguishable as predicted. This suggests that isotopologue-specific EAG amplitudes result from differential activation of specific olfactory receptors. In support of this, odorants with as few as two deuteria evoke distinct EAG amplitudes from their normal isotopologues, and this is independent of the size of the deuterated molecule. Importantly, we find no evidence that these isotopologue-specific amplitudes depend on perireceptor mechanisms or other pertinent physical property of the deuterated odorants. Rather, our results strongly suggest that Drosophilid olfactory receptors are activated by molecular vibrations differentiating similarly sized and shaped odorants in vivo, yielding sufficient differential information to drive behavioral choices. PMID:27351023

  2. Perception of odor-induced tastes following insular cortex lesion.

    PubMed

    Stevenson, Richard J; Miller, Laurie A; McGrillen, Ky

    2015-02-01

    Lesions of the insula can affect olfaction and gustation. Here, we examined the effect of insula lesions on taste and taste-like experiences generated via smelling (i.e., odor-induced tastes) in patients with focal insula lesions and intact olfaction. From a set of 16 patients with lesions to the insula, we found 7 (6 with right-sided lesions) who performed normally on various olfactory measures. These were compared to 42 normal control subjects on tests of gustatory and odor-induced taste perception as well as control measures. The patients were impaired relative to controls on most gustatory measures. They were also impaired on tests of odor-induced taste perception, primarily for stimuli presented on the left side. Examining cases individually revealed evidence of a dissociation: two patients exhibited no impairment in odor-induced taste perception in spite of gustatory deficits. Together, these findings suggest that the insula mediates taste recognition, hedonics, and intensity judgments as well as odor-induced taste perception. However, the areas responsible for aspects of taste perception and those responsible for odor-induced taste do not fully overlap each other and they are also independent of olfactory areas. PMID:24308589

  3. Characterization of major offensive odorants released from lake sediment

    NASA Astrophysics Data System (ADS)

    Susaya, Janice; Kim, Ki-Hyun; Chang, Yoon-Seok

    2011-02-01

    The amount of odorants effused from Lake Sihwa during the low tide period was estimated using sediment samples collected from various sites. A wide variety of odorants released from lake sediment were measured such as reduced sulfur compounds (RSCs), aldehydes, nitrogenous compounds, volatile organic compounds (VOCs), and volatile fatty acids (VFAs). A comparison of emission rates (μg m -2 min -1) showed large mean values from such species as NH 3 (14,550), toluene (370), and DMS (106), while the lowest values were seen from VFAs and some VOCs. If their emission concentrations are converted into odor intensity (OI), the OI values were dominated by such odorants as NH 3 (2.07), H 2S (1.65), DMS (1.80), acetaldehyde (1.52), butyric acid (1.59), butyraldehyde (1.28), isovaleric acid (1.15), and valeric acid (0.78). The dilution to threshold (D/T) ratio derived on the basis of the air dilution sensory (ADS) test yielded a mean of 62 (range: 10-173); 19 out of 21 samples were seen to exceed the guideline D/T value of 15. The sum of odor intensities derived from individual odorants exhibited strong compatibilities with the D/T ratio ( r2 = 0.87; α = 0.003). The overall results of this study confirm that the sediment can play an important role in the malodor phenomenon in the area surrounding the Lake Sihwa.

  4. Canine detection odor signatures for mine-related explosives

    NASA Astrophysics Data System (ADS)

    Johnston, James M.; Williams, Marc; Waggoner, L. Paul; Edge, Cindy C.; Dugan, Regina E.; Hallowell, Susan F.

    1998-09-01

    Dogs are capable of detecting and discriminating a number of compounds constituting a complex odor. However, they use only a few of these to recognize a substance. The focus of this research is to determine the compounds dogs learn to use in recognizing explosives used in land mines. This is accomplished by training dogs under behavioral laboratory conditions to respond differentially on separate levers to (1) blank air, (2) a target odor such as an explosive, and (3) all other odors (non-target odors). Vapor samples are generated by a serial dilution vapor generator whose operation and output is characterized by GC/MS. Once dogs learn this three-lever discrimination, testing sessions are conducted containing a number of probe trials in which vapor from constituent compounds is presented. Which lever the dogs respond to on these probe trials indicates whether they can smell the compound at all (blank lever) or whether it smells like the target odor (e.g., the explosive) or like something else. This method was conducted using TNT and C-4. The data show the dogs' reactions to each of the constituent compounds tested for each explosive. Analysis of these data reveal the canine detection odor signature for these explosives.

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

    PubMed

    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. PMID:24628891

  6. Stable odor recognition by a neuro-adaptive electronic nose.

    PubMed

    Martinelli, Eugenio; Magna, Gabriele; Polese, Davide; Vergara, Alexander; Schild, Detlev; Di Natale, Corrado

    2015-01-01

    Sensitivity, selectivity and stability are decisive properties of sensors. In chemical gas sensors odor recognition can be severely compromised by poor signal stability, particularly in real life applications where the sensors are exposed to unpredictable sequences of odors under changing external conditions. Although olfactory receptor neurons in the nose face similar stimulus sequences under likewise changing conditions, odor recognition is very stable and odorants can be reliably identified independently from past odor perception. We postulate that appropriate pre-processing of the output signals of chemical sensors substantially contributes to the stability of odor recognition, in spite of marked sensor instabilities. To investigate this hypothesis, we use an adaptive, unsupervised neural network inspired by the glomerular input circuitry of the olfactory bulb. Essentially the model reduces the effect of the sensors' instabilities by utilizing them via an adaptive multicompartment feed-forward inhibition. We collected and analyzed responses of a 4 × 4 gas sensor array to a number of volatile compounds applied over a period of 18 months, whereby every sensor was sampled episodically. The network conferred excellent stability to the compounds' identification and was clearly superior over standard classifiers, even when one of the sensors exhibited random fluctuations or stopped working at all. PMID:26043043

  7. Functional analysis of a mammalian odorant receptor subfamily

    PubMed Central

    Abaffy, Tatjana; Matsunami, Hiroaki; Luetje, Charles W.

    2014-01-01

    Phylogenetic analysis groups mammalian odorant receptors into two broad classes and numerous subfamilies. These subfamilies are proposed to reflect functional organization. Testing this idea requires an assay allowing detailed functional characterization of odorant receptors. Here we show that a variety of Class I and Class II mouse odorant receptors can be functionally expressed in Xenopus laevis oocytes. Receptor constructs included the N-terminal 20 residues of human rhodopsin and were coexpressed with Gαolf and the cystic fibrosis transmembrane regulator to allow electrophysiological measurement of receptor responses. For most mouse odorant receptors tested, these conditions were sufficient for functional expression. Co-expression of accessory proteins was required to allow functional surface expression of some mouse odorant receptors. We used this assay to examine the receptive ranges of all members of the MOR42 subfamily. MOR42-1 responded to dicarboxylic acids, preferring a 10–12 carbon chain length. MOR42-2 responded to monocarboxylic acids (7–10 carbons). MOR42-3 responded to dicarboxylic acids (8–10 carbons) and monocarboxylic acids (10–12 carbons). Thus, the receptive range of each receptor was unique. However, overlap between the individual receptive ranges suggests that the members of this subfamily form one contiguous subfamily receptive range, suggesting that odorant receptor subfamilies do constitute functional units. PMID:16606354

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

    ERIC Educational Resources Information Center

    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.…

  9. Determination of roasted pistachio (Pistacia vera L.) key odorants by headspace solid-phase microextraction and gas chromatography-olfactometry.

    PubMed

    Aceña, Laura; Vera, Luciano; Guasch, Josep; Busto, Olga; Mestres, Montserrat

    2011-03-23

    Key odorants in roasted pistachio nuts have been determined for the first time. Two different pistachio varieties (Fandooghi and Kerman) have been analyzed by means of headspace solid-phase microextraction (HS-SPME) and gas chromatography-olfactometry (GCO). The aroma extract dilution analyses (AEDA) applied have revealed 46 and 41 odor-active regions with a flavor dilution (FD) factor≥64 for the Fandooghi and the Kerman varieties, respectively, and 39 of them were related to precisely identified compounds. These included esters, pyrazines, aldehydes, acids, furans, and phenols. The results show that the Fandooghi variety presents, not only more odor-active regions but also higher FD factors than the Kerman variety that can lead to the conclusion that the first variety has a richer aromatic profile than the second one. The descriptive sensory analysis (DSA) showed that the roasted, chocolate/coffee, and nutty attributes were rated significantly higher in the Fandooghi variety, whereas the green attribute was significantly higher in the Kerman one. PMID:21329356

  10. Postharvest treatments of fresh produce.

    PubMed

    Mahajan, P V; Caleb, O J; Singh, Z; Watkins, C B; Geyer, M

    2014-06-13

    Postharvest technologies have allowed horticultural industries to meet the global demands of local and large-scale production and intercontinental distribution of fresh produce that have high nutritional and sensory quality. Harvested products are metabolically active, undergoing ripening and senescence processes that must be controlled to prolong postharvest quality. Inadequate management of these processes can result in major losses in nutritional and quality attributes, outbreaks of foodborne pathogens and financial loss for all players along the supply chain, from growers to consumers. Optimal postharvest treatments for fresh produce seek to slow down physiological processes of senescence and maturation, reduce/inhibit development of physiological disorders and minimize the risk of microbial growth and contamination. In addition to basic postharvest technologies of temperature management, an array of others have been developed including various physical (heat, irradiation and edible coatings), chemical (antimicrobials, antioxidants and anti-browning) and gaseous treatments. This article examines the current status on postharvest treatments of fresh produce and emerging technologies, such as plasma and ozone, that can be used to maintain quality, reduce losses and waste of fresh produce. It also highlights further research needed to increase our understanding of the dynamic response of fresh produce to various postharvest treatments. PMID:24797137

  11. Postharvest treatments of fresh produce

    PubMed Central

    Mahajan, P. V.; Caleb, O. J.; Singh, Z.; Watkins, C. B.; Geyer, M.

    2014-01-01

    Postharvest technologies have allowed horticultural industries to meet the global demands of local and large-scale production and intercontinental distribution of fresh produce that have high nutritional and sensory quality. Harvested products are metabolically active, undergoing ripening and senescence processes that must be controlled to prolong postharvest quality. Inadequate management of these processes can result in major losses in nutritional and quality attributes, outbreaks of foodborne pathogens and financial loss for all players along the supply chain, from growers to consumers. Optimal postharvest treatments for fresh produce seek to slow down physiological processes of senescence and maturation, reduce/inhibit development of physiological disorders and minimize the risk of microbial growth and contamination. In addition to basic postharvest technologies of temperature management, an array of others have been developed including various physical (heat, irradiation and edible coatings), chemical (antimicrobials, antioxidants and anti-browning) and gaseous treatments. This article examines the current status on postharvest treatments of fresh produce and emerging technologies, such as plasma and ozone, that can be used to maintain quality, reduce losses and waste of fresh produce. It also highlights further research needed to increase our understanding of the dynamic response of fresh produce to various postharvest treatments. PMID:24797137

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

    PubMed Central

    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. Identification, quantification and treatment of fecal odors released into the air at two wastewater treatment plants.

    PubMed

    Zhou, Yubin; Hallis, Samantha A; Vitko, Tadeo; Suffet, Irwin H Mel

    2016-09-15

    Odorous emissions from wastewater treatment plants (WWTPs) are an annoyance for neighboring communities. This article, for the first time, quantitatively reports on an evaluation of the presence of fecal odorants identified in air samples from two exemplary WWTPs by the odor profile method (OPM) and chemical analysis. The fecal odorants indole and skatole were identified by Gas Chromatography-Mass Spectrometry. The odor threshold concentration of skatole was determined to be 0.327 ng/L (60 pptV) in Teflon Bags by an expert panel. Skatole was found to be the primary chemical leading to fecal odor, due to its odor concentration to odor threshold concentration ratio that ranged from 2.8 to 22.5. The Weber-Fechner law was followed by pure skatole, but was not applicable when there was a mixture of fecal odorants and other odorant types present in WWTP air emission samples. This is probably caused by antagonism with other odorant types. Several existing odor control treatment methods for fecal odorants were evaluated at different wastewater treatment operations at two WWTPs by the OPM and chemical analysis for indole and skatole. Chemical scrubbing and biofiltration performed best in removing fecal odors among current control technologies. PMID:27235805

  14. Odor characterization from barns and slurry treatment facilities at a commercial swine facility in South Korea

    NASA Astrophysics Data System (ADS)

    Jo, Sang-Hee; Kim, Ki-Hyun; Jeon, Byong-Hun; Lee, Min-Hee; Kim, Yong-Hyun; Kim, Bo-Won; Cho, Sung-Back; Hwang, Ok-Hwa; Bhattacharya, Satya Sundar

    2015-10-01

    In this study, emission characteristics of major odorants in pig confinement facilities were investigated through comparative analysis between odorant composition and odor intensity. Odorant samples in ambient air were collected from five different paired sampling sites: (1) in- and outside of windowless pig barn, (2) in- and outside of open pig barn, (3) before/after slurry treatment (via liquid fertilization), (4) before/after composting, and (5) two reference background sites on a pig confinement facility. A total of 47 compounds consisting of key offensive odorants (such as reduced sulfur and volatile organic compounds) were measured from each selected site. When the results are compared in terms of odor intensity, a list of odorants (sulfur compounds, volatile fatty acids, phenols, and indoles) were generally seen at enhanced levels on most sites. In two types of pig barn facilities (windowless ('W') and open ('O')), butyric and valeric acid were the predominant species. The removal efficiency of odorants was quite different between the two slurry treatment approaches of composting and liquid fertilization. Although the efficiencies of odor removal in the former were not sufficient, that of the latter was fairly significant in terms of odor intensity. However, some odorants like hydrogen sulfide, methanethiol, p-cresol, and butyric acid were still retained above the odor threshold level. Accordingly, odorant emissions from animal housing facilities can be characterized most effectively by key odorants such as volatile fatty acids and reduced sulfur species.

  15. Preventive control of odor emissions through manipulation of operational parameters during the active phase of composting.

    PubMed

    Zhang, Wenxiu; Lau, Anthony K; Wen, Zhiping S

    2009-06-01

    Better understanding of the effects of key operational parameters or environmental factors on odor emission is of critical importance for minimizing the generation of composting odors. A series of laboratory experiments was conducted to examine the effects of various operating conditions on odor emissions. The results revealed that airflow rates that were too high or too low could result in higher total odor emissions. An optimal flowrate for odor control would be approximately 0.6 L/min.kg dry matter with intermittent aeration and a duty cycle of 33%. Temperature setpoint at 60 degrees C appeared to be a turning point for odor emission. Below this point, odor emissions increased with increasing temperature setpoint; conversely, odor emissions decreased with increasing temperature setpoint above this point. With regard to the composting material properties, odor emissions were greatly affected by the initial moisture content of feedstock. Both peak odor concentration and emission rate generally increased with higher initial moisture content. Odor emission was significant only at moisture levels higher than 65%. An initial moisture level below 45% is not recommended due to concern with the resulting lower degree of biodegradation. Biodegradable volatile solids content (BVS) of feedstock had pronounced effect on odor emissions. Peak odor concentration and emission rate increased dramatically as BVS increased from 45% to 65%, thus, total odor emission increased exponentially with BVS. PMID:20183055

  16. Glycosidically bound aroma compounds and impact odorants of four strawberry varieties.

    PubMed

    Ubeda, Cristina; San-Juan, Felipe; Concejero, Belén; Callejón, Raquel M; Troncoso, Ana M; Morales, M Lourdes; Ferreira, Vicente; Hernández-Orte, Purificación

    2012-06-20

    This paper reports the determination of glycosidically bound aroma compounds and the olfactometric analysis in four strawberry varieties (Fuentepina, Camarosa, Candonga and Sabrina). Different hydrolytic strategies were also studied. The results showed significant differences between acid and enzymatic hydrolysis. In general terms, the greater the duration of acid hydrolysis, the higher was the content of norisoprenoids, volatile phenols, benzenes, lactones, Furaneol, and mesifurane. A total of 51 aglycones were identified, 38 of them unreported in strawberry. Olfactometric analyses revealed that the odorants with higher modified frequencies were Furaneol, γ-decalactone, ethyl butanoate, ethyl hexanoate, ethyl 3-methylbutanoate, diacetyl, hexanoic acid, and (Z)-1,5-octadien-3-one. This last compound, described as geranium/green/pepper/lettuce (linear retention index = 1378), was identified for the first time. Differences with regard to fruity, sweet, floral, and green aroma characters were observed among varieties. In Candonga and Fuentepina, the green character overpowered the sweet. In the other two strawberry varieties sweet attributes were stronger than the rest. PMID:22646744

  17. Odor and Odorous Compound Emissions from Manure of Swine Fed Standard and Dried Distillers Grains with Soluble Supplemented Diets.

    PubMed

    Trabue, Steven; Kerr, Brian; Scoggin, Kenwood

    2016-05-01

    This study was conducted to determine the impact of diets containing dried distillers grains with solubles (DDGS) 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 diet containing 35% DDGS over a 42-d feeding trial. Their waste was collected and transferred to individual manure storage containers. Manure from pigs fed diets containing DDGS had significantly lower odorant emissions expressed in animal units for hydrogen sulfide (HS) and ammonia (NH) ( < 0.05) compared with pigs fed the CSBM diet, but emissions of volatile fatty acids and phenolic compounds were significantly higher ( < 0.05) for manures from animals fed the DDGS diet. There was no significant difference for indole compound emissions due to the dietary treatment applied. Emissions of volatile organic compounds (VOCs) from manure accounted for less than 0.1% of carbon consumed for either diet. There were no significant differences in odor emissions for either diet as quantified with human panels or measured as the sum total of the odor activity value. Manure odors from pigs fed the CSBM diet were dominated by HS, whereas animals fed the diet containing DDGS were dominated by VOCs. PMID:27136158

  18. Patterned response to odor in single neurones of goldfish olfactory bulb: influence of odor quality and other stimulus parameters.

    PubMed

    Meredith, M; Moulton, D G

    1978-06-01

    Responses of 75 single units in the goldfish olfactory bulb were analyzed in detail for their relationship to the time-course of the change in odor concentration during each odor stimulus. Odor stimuli were controlled for rise time, duration, and peak concentration by an apparatus developed for the purpose. This apparatus enabled aqueous odor stimuli to be interposed into a constant water stream without changes in flow rate. The time-course of the concentration change within the olfactory sac was inferred from conductivity measurements at the incurrent and excurrent nostrils. Temporal patterns of firing rate elicited by stimuli with relatively slow rising and falling phases could be quite complex combinations of excitation and suppression. Different temporal patterns were produced by different substances at a single concentration in most units. Statistical measures of the temporal pattern of response for a small number of cells at a given concentration were more characteristic of the stimulus substance than any of three measures of magnitude of response. The temporal patterns change when the peak concentration, duration, and rise time of the stimuli are varied. The nature of these changes suggests that the different patterns are due primarily to the combined influence of two factors: (a) a stimulus whose concentration varies over time and (b) a relationship between concentration and impulse frequency which varies from unit to unit. Some units produce patterns suggestive of influence by neural events of long time constant. The importance of temporal patterns in odor quality and odor intensity coding is discussed. PMID:209126

  19. Understanding the underlying dimensions in perfumers' odor perception space as a basis for developing meaningful odor maps.

    PubMed

    Zarzo, Manuel; Stanton, David T

    2009-02-01

    Various low-dimensional perceptual maps of fragrances have been proposed in the literature, as well as sensory maps for the odor descriptors most frequently applied in perfumery. To reach a consensus, however, seems difficult, if at all possible. In the present study, we applied principal components analysis to two databases. The first contains numeric odor profiles of 309 compounds based on 30 descriptors. The loading plot corresponding to the relevant components was strikingly similar to the odor effects diagram proposed by P. Jellinek (1951), primarily on the basis of his long experience as a perfumer. We obtained similar results in our analysis of the second database, which comprises 66 descriptors and contains the semantic descriptions of 119 perfume materials. On the basis of the results of both analyses, a commercial map of fragrances is discussed. Our findings suggest that it is possible to develop standard sensory maps of perfumery odor descriptors, if a consensus is first reached regarding which odorants best represent particular odor qualities. PMID:19304614

  20. Greene Machine

    ERIC Educational Resources Information Center

    Cavanagh, Sean

    2004-01-01

    The author of this article profiles the 37-year-old researcher Jay P. Greene and his controversial research studies on education. Most people learn early to trust the things they see first, but Greene adheres to a different creed. People are deceived by their own eyes. He believed that visual betrayal is as evident as it is in how people think…

  1. Transmission of cotton (Gossypium hirsutum) seed and boll rotting bacteria by southern green stink bugs (Nezara viridula L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this study is to determine the ability of the southern green stink bug (Nezara viridula L.) to transmit an opportunistic Pantoea agglomerans strain into unopened, green cotton (Gossypium hirsutum) bolls. Southern green stink bug (SGSB) colonies were reared on fresh green beans in the labo...

  2. Odor Recognition vs. Classification in Artificial Olfaction

    NASA Astrophysics Data System (ADS)

    Raman, Baranidharan; Hertz, Joshua; Benkstein, Kurt; Semancik, Steve

    2011-09-01

    Most studies in chemical sensing have focused on the problem of precise identification of chemical species that were exposed during the training phase (the recognition problem). However, generalization of training to predict the chemical composition of untrained gases based on their similarity with analytes in the training set (the classification problem) has received very limited attention. These two analytical tasks pose conflicting constraints on the system. While correct recognition requires detection of molecular features that are unique to an analyte, generalization to untrained chemicals requires detection of features that are common across a desired class of analytes. A simple solution that addresses both issues simultaneously can be obtained from biological olfaction, where the odor class and identity information are decoupled and extracted individually over time. Mimicking this approach, we proposed a hierarchical scheme that allowed initial discrimination between broad chemical classes (e.g. contains oxygen) followed by finer refinements using additional data into sub-classes (e.g. ketones vs. alcohols) and, eventually, specific compositions (e.g. ethanol vs. methanol) [1]. We validated this approach using an array of temperature-controlled chemiresistors. We demonstrated that a small set of training analytes is sufficient to allow generalization to novel chemicals and that the scheme provides robust categorization despite aging. Here, we provide further characterization of this approach.

  3. Complex and non-redundant signals from individual odor receptors that underlie chemotaxis behavior in Drosophila melanogaster larvae

    PubMed Central

    Grewal, Jeewanjot S.; Nguyen, Christine; Robles, Raquel; Cho, Christina; Kir, Karolina; Fledderman, Nicole; Gacharna, George; Wesolowski, Michael; Klinger, Christie; Vallejo, Pedro; Menhennett, Lorien; Nagaraj, Abhiram; Ebo, Chineze; Peacy, Garrett; Davelis, Eftihia; Kucher, David; Giers, Sarah; Kreher, Scott A.

    2014-01-01

    ABSTRACT The rules by which odor receptors encode odors and allow behavior are still largely unexplored. Although large data sets of electrophysiological responses of receptors to odors have been generated, few hypotheses have been tested with behavioral assays. We use a data set on odor responses of Drosophila larval odor receptors coupled with chemotaxis behavioral assays to examine rules of odor coding. Using mutants of odor receptors, we have found that odor receptors with similar electrophysiological responses to odors across concentrations play non-redundant roles in odor coding at specific odor concentrations. We have also found that high affinity receptors for odors determine behavioral response thresholds, but the rules for determining peak behavioral responses are more complex. While receptor mutants typically show loss of attraction to odors, some receptor mutants result in increased attraction at specific odor concentrations. The odor receptor mutants were rescued using transgenic expression of odor receptors, validating assignment of phenotypes to the alleles. Vapor pressures alone cannot fully explain behavior in our assay. Finally, some odors that did not elicit strong electrophysiological responses are associated with behavioral phenotypes upon examination of odor receptor mutants. This result is consistent with the role of sensory neurons in lateral inhibition via local interneurons in the antennal lobe. Taken together, our results suggest a complexity of odor coding rules even in a simple olfactory sensory system. PMID:25238759

  4. Salmonella surveillance on fresh produce in retail in Turkey.

    PubMed

    Gunel, Elif; Polat Kilic, Gozde; Bulut, Ece; Durul, Bora; Acar, Sinem; Alpas, Hami; Soyer, Yeşim

    2015-04-16

    Although Turkey is one of the major producers of fruits and vegetables in the world, there has been no information available on the prevalence of pathogens in fresh produce. To fill this gap, we collected 503 fresh produce samples including tomato, parsley, iceberg lettuce, green-leaf lettuce and five different fresh pepper varieties (i.e., green, kapya, bell, mazamort and Charleston) from 3 major districts within 9 supermarkets and 3 bazaars in Ankara, Turkey to investigate the presence of Salmonella. Salmonella was detected in 0.8% (4/503) of samples by conventional culturing method with molecular confirmation conducted through polymerase chain reaction (PCR). For further characterization of isolates, serotyping, antimicrobial susceptibility testing, multi-locus sequence typing (MLST; aroC, thrA, purE, sucA, hisD, hemD and dnaN) and pulsed-field gel electrophoresis (PFGE) were performed. Salmonella enterica subsp. enterica serotypes Anatum, Charity, Enteritidis and Mikawasima were isolated from two parsley, one pepper and one lettuce samples, respectively. MLST resulted in 4 sequence types (STs) for each serotype, including one novel ST for serotype Mikawasima. Similarly, PFGE revealed four different XbaI PFGE patterns. The results of this survey, obtained by the most common subtyping methods (i.e. serotyping, MLST and PFGE) worldwide, contributes to the development of a national database in Turkey, which is essential for investigating the evolutionary pathways, geographical distribution and genetic diversity of Salmonella strains. PMID:25643853

  5. Improved performance on clerical tasks associated with administration of peppermint odor.

    PubMed

    Barker, Shannon; Grayhem, Pamela; Koon, Jerrod; Perkins, Jessica; Whalen, Allison; Raudenbush, Bryan

    2003-12-01

    Previous research indicates the presence of certain odors is associated with enhanced task performance. The present study investigated use of peppermint odor during typing performance, memorization, and alphabetization. Participants completed the protocol twice--once with peppermint odor present and once without. Analysis indicated significant differences in the gross speed, net speed, and accuracy on the typing task, with odor associated with improved performance. Alphabetization also improved significantly under the odor condition but not typing duration or memorization. These results suggest peppermint odor may promote a general arousal of attention, so participants stay focused on their task and increase performance. PMID:14738372

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

    PubMed

    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

  7. Odors Bias Time Perception in Visual and Auditory Modalities

    PubMed Central

    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

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

    PubMed

    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. PMID:26471840

  9. 21 CFR 101.95 - “Fresh,” “freshly frozen,” “fresh frozen,” “frozen fresh.”

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false âFresh,â âfreshly frozen,â âfresh frozen,â âfrozen... frozen,” “fresh frozen,” “frozen fresh.” The terms defined in this section may be used on the label or in... state and has not been frozen or subjected to any form of thermal processing or any other form...

  10. 21 CFR 101.95 - “Fresh,” “freshly frozen,” “fresh frozen,” “frozen fresh.”

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false âFresh,â âfreshly frozen,â âfresh frozen,â âfrozen... frozen,” “fresh frozen,” “frozen fresh.” The terms defined in this section may be used on the label or in... state and has not been frozen or subjected to any form of thermal processing or any other form...

  11. 21 CFR 101.95 - “Fresh,” “freshly frozen,” “fresh frozen,” “frozen fresh.”

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false âFresh,â âfreshly frozen,â âfresh frozen,â âfrozen... frozen,” “fresh frozen,” “frozen fresh.” The terms defined in this section may be used on the label or in... state and has not been frozen or subjected to any form of thermal processing or any other form...

  12. 21 CFR 101.95 - “Fresh,” “freshly frozen,” “fresh frozen,” “frozen fresh.”

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false âFresh,â âfreshly frozen,â âfresh frozen,â âfrozen... frozen,” “fresh frozen,” “frozen fresh.” The terms defined in this section may be used on the label or in... state and has not been frozen or subjected to any form of thermal processing or any other form...

  13. Evaluation of the Role of G Protein-Coupled Receptor Kinase 3 in Desensitization of Mouse Odorant Receptors in a Mammalian Cell Line and in Olfactory Sensory Neurons

    PubMed Central

    Kato, Aya; Reisert, Johannes; Ihara, Sayoko; Yoshikawa, Keiichi

    2014-01-01

    Thousands of odors are sensed and discriminated by G protein-coupled odorant receptors (ORs) expressed in olfactory sensory neurons (OSNs). G protein-coupled receptor kinases (GRKs) may have a role in desensitization of ORs. However, whether ORs are susceptible to agonist-dependent desensitization and whether GRKs affect odorant responsiveness of OSNs are currently unknown. Here we show that GRK3 attenuated the agonist responsiveness of a specific mouse odorant receptor for eugenol (mOR-EG) upon agonist pretreatment in HEK293 cells, but GRK3 did not affect the response amplitude or the recovery kinetics upon repeated agonist stimulation. We performed electrophysiological recordings of single OSNs which expressed mOR-EG and green fluorescent protein (GFP) in the presence or absence of GRK3. The kinetics and amplitude of agonist responsiveness of individual GFP-labeled mOR-EG neurons were not significantly affected by the absence of GRK3. These results indicate that the role of GRK3 in attenuating ORs responsiveness in OSNs may have been overestimated. PMID:25313015

  14. 7 CFR 51.574 - Green.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Green. 51.574 Section 51.574 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946 FRESH FRUITS, VEGETABLES AND OTHER...

  15. Odorants of different chemical classes interact with distinct odorant binding protein subtypes.

    PubMed

    Löbel, Dietrich; Jacob, Marion; Völkner, Meike; Breer, Heinz

    2002-01-01

    The ligand profile for three odorant binding proteins (OBPs) of the rat have been determined using a large number of odorous compounds from different chemical classes. To evaluate the binding spectra of distinct subtypes, all OBPs were produces in Escherichia coli as recombinant His-tagged fusion proteins. The individual binding properties of each OBP subtype were analysed using a large array of organic compounds, representing derivatives of aliphatic and aromatic compounds, as well as terpenes, pyrazines and thiazoles, in a competitive spectroscopic binding assay with various fluorescence chromophores as the specific interacting partner for the OBPs. Most of the compounds were identified to interact only with one OBP subtype. But interestingly, a small change, for example in the 2-methyl or 2-ethoxy side chain in the pyrazine and thiazole derivatives to a 2-isobutyl group, caused overlapping binding affinities to rat-OBP1 and rat-OBP3. However, the data strongly support the notion that each OBP subtype displays a characteristic ligand binding profile and interacts with a different subset of exogenous organic compounds in a micromolar range. PMID:11751466

  16. Tailoring the fresh state properties of concrete

    NASA Astrophysics Data System (ADS)

    Tregger, Nathan Allen

    In this research, two types of concrete whose performance relies on their fresh-state abilities will be discussed. The first is self-consolidating concrete, which possesses high flowability without aggregate segregation. Quality control of flowability is typically predicted by the final diameter ( Df) of the slump-flow test, which in turn, has been related to yield stress of the fresh concrete. Currently, there are no reliable measures of viscosity from a field-friendly test such as the slump-flow test. It will be demonstrated that the viscosity can be related to the time to final diameter (Tf) from the minislump-flow tests for cement pastes. This relationship is extended to concrete systems where T f of the slump-flow test is correlated to dynamic segregation. For the concrete system, Tf was increased systematically using a viscosity modifying agent, while the Df was kept constant by adjusting the superplasticizer content. Segregation is determined by measuring the radial aggregate distribution from the slump-flow test. The results demonstrate that increasing the Tf improves dynamic segregation resistance. Furthermore, Tf was more indicative of viscosity than the time to reach a diameter of 50 cm (T50), which is currently used in the field as a measure of viscosity. Computational models are implemented to investigate these relationships for both cement and concrete systems. The second type of concrete is an improved slipform concrete with the ability to consolidate under minimal external energy yet maintain shape stability after being slipformed. This balance between flowability and shape stability is achieved through combination of fly ash and small dosages of micro and nano clays. A microstructural investigation of the effect of clays on the fresh state is carried out to relate macro behaviors with changes in the paste microstructure. Shear and compressive rheology techniques are used to measure how the solids volume fraction of the suspensions with different

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

    PubMed

    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. PMID:26489214

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

    PubMed Central

    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

  19. Mapping of Learned Odor-Induced Motivated Behaviors in the Mouse Olfactory Tubercle.

    PubMed

    Murata, Koshi; Kanno, Michiko; Ieki, Nao; Mori, Kensaku; Yamaguchi, Masahiro

    2015-07-22

    An odor induces food-seeking behaviors when humans and animals learned to associate the odor with food, whereas the same odor elicits aversive behaviors following odor-danger association learning. It is poorly understood how central olfactory circuits transform the learned odor cue information into appropriate motivated behaviors. The olfactory tubercle (OT) is an intriguing area of the olfactory cortex in that it contains medium spiny neurons as principal neurons and constitutes a part of the ventral striatum. The OT is therefore a candidate area for participation in odor-induced motivated behaviors. Here we mapped c-Fos activation of medium spiny neurons in different domains of the mouse OT following exposure to learned odor cues. Mice were trained to associate odor cues to a sugar reward or foot shock punishment to induce odor-guided approach behaviors or aversive behaviors. Regardless of odorant types, the anteromedial domain of the OT was activated by learned odor cues that induced approach behaviors, whereas the lateral domain was activated by learned odor cues that induced aversive behaviors. In each domain, a larger number of dopamine receptor D1 type neurons were activated than D2 type neurons. These results indicate that specific domains of the OT represent odor-induced distinct motivated behaviors rather than odor stimuli, and raise the possibility that neuronal type-specific activation in individual domains of the OT plays crucial roles in mediating the appropriate learned odor-induced motivated behaviors. Significance statement: Although animals learn to associate odor cues with various motivated behaviors, the underlying circuit mechanisms are poorly understood. The olfactory tubercle (OT), a subarea of the olfactory cortex, also constitutes the ventral striatum. Here, we trained mice to associate odors with either reward or punishment and mapped odor-induced c-Fos activation in the OT. Regardless of odorant types, the anteromedial domain was

  20. Odor identity influences tracking of temporally patterned plumes in Drosophila

    PubMed Central

    2011-01-01

    Background Turbulent fluid landscapes impose temporal patterning upon chemical signals, and the dynamical neuronal responses to patterned input vary across the olfactory receptor repertoire in flies, moths, and locusts. Sensory transformations exhibit low pass filtering that ultimately results in perceptual fusion of temporally transient sensory signals. For example, humans perceive a sufficiently fast flickering light as continuous, but the frequency threshold at which this fusion occurs varies with wavelength. Although the summed frequency sensitivity of the fly antenna has been examined to a considerable extent, it is unknown how intermittent odor signals are integrated to influence plume tracking behavior independent of wind cues, and whether temporal fusion for behavioral tracking might vary according to the odor encountered. Results Here we have adopted a virtual reality flight simulator to study the dynamics of plume tracking under different experimental conditions. Flies tethered in a magnetic field actively track continuous (non-intermittent) plumes of vinegar, banana, or ethyl butyrate with equal precision. However, pulsing these plumes at varying frequency reveals that the threshold rate, above which flies track the plume as if it were continuous, is unique for each odorant tested. Thus, the capability of a fly to navigate an intermittent plume depends on the particular odorant being tracked during flight. Finally, we measured antennal field potential responses to an intermittent plume, found that receptor dynamics track the temporal pattern of the odor stimulus and therefore do not limit the observed behavioral temporal fusion limits. Conclusions This study explores the flies' ability to track odor plumes that are temporally intermittent. We were surprised to find that the perceptual critical fusion limit, determined behaviorally, is strongly dependent on odor identity. Antennal field potential recordings indicate that peripheral processing of temporal

  1. From Cassyrane to cashmeran - the molecular parameters of odorants.

    PubMed

    Kraft, Philip; Di Cristofaro, Valeria; Jordi, Samuel

    2014-10-01

    This review, including some new experimental results, is the summary of a talk at the 'flavors & fragrances 2013' conference in Leipzig, organized jointly by the GDCh, the Liebig-Vereinigung, and the EuCheMS. After times of searching for natural odor principles and serendipitous discoveries by chemical inspiration, directed odorant design today offers the highest hit rates for the discovery of new odorants, although serendipity still plays a role. Keeping intact the electronic shape required for a certain olfactophore-binding geometry, one can add or subtract structural elements, rigidify molecular structures, or introduce more structural flexibility. To find out which structural features are critical, the 'seco-approach', in which different fragments are removed by cutting strategic bonds, is the most analytical. Following this approach, such ingredients as Serenolide, Sylkolide, and Pomarose were designed. Transferring this design principle from the family of damascones to that of the theaspiranes led to the discovery of Cassyrane, though completely different structural features turned out to be relevant. Application of the seco-concept to a 3,7a-substituted 2,6,7,7a-tetrahydro-1H-inden-5-yl musk lead structure derived from carotol resulted in the discovery of a new family of dienone musks with novel structure-odor correlations. However, cutting the C(2)-O bond of Cassyrane and oxidizing the resulting seco-structure to the 1,2,5,1″-tetradehydro derivative links the family of dienone musks with that of blackcurrant odorants, but the resulting target structures turned out to be potent orris odorants. (3E,5E)-5-(tert-Butyl)octadeca-3,5-dien-2-one even possesses the lowest odor threshold in the whole ionone family (0.036 ng/l air), which could be rationalized by a superposition analysis on (-)-cis-γ-irone. In the course of the synthesis of these high-impact orris odorants, we discovered that, depending on the reaction conditions, the dehydration step of the

  2. Sweet reward increases implicit discrimination of similar odors.

    PubMed

    Pool, Eva; Delplanque, Sylvain; Porcherot, Christelle; Jenkins, Tatiana; Cayeux, Isabelle; Sander, David

    2014-01-01

    Stimuli associated with emotional events signal the presence of potentially relevant situations, thus learning to rapidly identify this kind of stimuli can be highly beneficial. It has been demonstrated that individuals acquire a better perceptual representation of stimuli associated with negative and threatening emotional events. Here we investigated whether the same process occurs for stimuli associated with positive and rewarding emotional events. We used an appetitive Pavlovian conditioning paradigm during which one of two perceptually non-distinguishable odors was associated with a rewarding taste (i.e., chocolate). We investigated whether appetitive conditioning could improve the recognition of the odor associated with the reward, rendering it discriminable from its similar version that was never associated with the reward. Results revealed a dissociation between explicit perception and physiological reactions. Although participants were not able to explicitly perceive a difference, they reacted faster, inhaled more and had higher skin conductance responses when confronted with the reward-associated odor compared to its similar version that was never associated with the reward. Our findings have demonstrated that positive emotional associations can improve the implicit perceptual representation of odors, by triggering different physiological responses to odors that do not seem to be otherwise distinguishable. PMID:24834039

  3. Sweet reward increases implicit discrimination of similar odors

    PubMed Central

    Pool, Eva; Delplanque, Sylvain; Porcherot, Christelle; Jenkins, Tatiana; Cayeux, Isabelle; Sander, David

    2014-01-01

    Stimuli associated with emotional events signal the presence of potentially relevant situations, thus learning to rapidly identify this kind of stimuli can be highly beneficial. It has been demonstrated that individuals acquire a better perceptual representation of stimuli associated with negative and threatening emotional events. Here we investigated whether the same process occurs for stimuli associated with positive and rewarding emotional events. We used an appetitive Pavlovian conditioning paradigm during which one of two perceptually non-distinguishable odors was associated with a rewarding taste (i.e., chocolate). We investigated whether appetitive conditioning could improve the recognition of the odor associated with the reward, rendering it discriminable from its similar version that was never associated with the reward. Results revealed a dissociation between explicit perception and physiological reactions. Although participants were not able to explicitly perceive a difference, they reacted faster, inhaled more and had higher skin conductance responses when confronted with the reward-associated odor compared to its similar version that was never associated with the reward. Our findings have demonstrated that positive emotional associations can improve the implicit perceptual representation of odors, by triggering different physiological responses to odors that do not seem to be otherwise distinguishable. PMID:24834039

  4. Proposed Objective Odor Control Test Methodology for Waste Containment

    NASA Technical Reports Server (NTRS)

    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.

  5. Numerical modeling of odorant uptake in the rat nasal cavity.

    PubMed

    Yang, Geoffrey C; Scherer, Peter W; Zhao, Kai; Mozell, Maxwell M

    2007-03-01

    An anatomically accurate 3-dimensional numerical model of the right rat nasal cavity was developed and used to compute low, medium, and high flow rate inspiratory and expiratory mucosal odorant uptake (imposed patterning) for 3 odorants with different mucus solubilities. The computed surface mass flux distributions were compared with anatomic receptor gene expression zones identified in the literature. In general, simulations predicted that odorants that were highly soluble in mucus were absorbed dorsally and medially, corresponding roughly to receptors from one of the gene expression zones. Insoluble odorants tended to be absorbed more peripherally in the rat olfactory region corresponding to the other 2 zones. These findings also agreed in general with the electroolfactogram measurements and the voltage-sensitive dye measurements reported in the literature. This numerical approach is the first to predict detailed odorant flux information across the olfactory mucosa in the rat nasal cavity during inspiratory and expiratory flow and to relate it to anatomic olfactory receptor location, physiological function, and biochemical experiment. This numerical technique can allow us to separate the contributions of imposed and inherent patterning mechanisms on the rat olfactory mucosa. PMID:17220517

  6. Unexpected plant odor responses in a moth pheromone system.

    PubMed

    Rouyar, Angéla; Deisig, Nina; Dupuy, Fabienne; Limousin, Denis; Wycke, Marie-Anne; Renou, Michel; Anton, Sylvia

    2015-01-01

    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 toward 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. PMID:26029117

  7. Unexpected plant odor responses in a moth pheromone system

    PubMed Central

    Rouyar, Angéla; Deisig, Nina; Dupuy, Fabienne; Limousin, Denis; Wycke, Marie-Anne; Renou, Michel; Anton, Sylvia

    2015-01-01

    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 toward 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. PMID:26029117

  8. Odorant-regulated Ca2+ gradients in rat olfactory neurons.

    PubMed

    Restrepo, D; Okada, Y; Teeter, J H

    1993-11-01

    Olfactory neurons respond to odors with a change in conductance that mediates an influx of cations including Ca2+. The concomitant increase in [Cai] has been postulated to play a role in the adaptation to maintained odorant stimulation (Kurahashi, T., and T. Shibuya. 1990. Brain Research. 515:261-268. Kramer, R. H., and S. A. Siegelbaum. 1992. Neuron. 9:897-906. Zufall, F., G. M. Shepherd, and S. Firestein. 1991. Proceedings of the Royal Society of London, B. 246:225-230.) We have imaged the distribution of [Cai] in rat olfactory neurons (RON) using the Ca2+ indicator fura-2. A large percentage of the RON (42%, n = 35) responded to odorants with an increase in [Cai]. About half of the responding neurons displayed an increase in [Cai] at the apical end of the cell, but not at the soma. Moreover, in those cells that responded to odors with a standing [Cai] gradient, the gradient could be maintained for long periods of time (minutes) provided that the cells were continuously stimulated. In contrast, K(+)-induced depolarization elicited a more homogeneous increase in [Cai]. The spatially inhomogeneous increase in [Cai] elicited by odorants in some cells has important implications for the role of Ca2+ in adaptation because channels and enzymes regulated by Ca2+ will be affected differently depending on their location. PMID:8301263

  9. Treatment of unpleasant odors in municipal wastewater treatment plants.

    PubMed

    Karageorgos, Petros; Latos, Manolis; Kotsifaki, Christina; Lazaridis, Mihalis; Kalogerakis, Nicolas

    2010-01-01

    The purpose of this paper to present a case study on how to address the odor problem from secondary sources within a municipal wastewater treatment plant (WWTP) by first identifying the locations of the problem and second by evaluating alternative treatment technologies. The WWTP of Chania is a typical 100,000 equivalent inhabitants-facility in a warm semi-arid environment which is located close to residential areas. The installation of a chemical scrubber to control major odor sources within the plant did not succeed in eliminating complaints by nearby residents, and additional measures were required. In this case study we identify all major secondary sources of odor within the plant and evaluate the effectiveness of the different technologies that were employed to address this problem (cover installation, gas and liquid phase oxidation, activated carbon/permanganate absorption, FeCl(3) addition). In particular, we found that installation of covers and reduction of turbulence at two key locations within the WWTP was the best strategy to combat unpleasant odors. Furthermore, when the central chemical scrubber was near capacity the installation of an auxiliary system of activated carbon absorption coupled to permanganate oxidation was deemed to be a safe approach. However, despite the very high removal efficiency (>99.5%) of the unit, the addition of FeCl(3) in the liquid phase was required in order to achieve complete deodorization (below the human odor threshold level). PMID:20453338

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

    NASA Astrophysics Data System (ADS)

    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.

  11. Processing of odor mixtures in the zebrafish olfactory bulb.

    PubMed

    Tabor, Rico; Yaksi, Emre; Weislogel, Jan-Marek; Friedrich, Rainer W

    2004-07-21

    Components of odor mixtures often are not perceived individually, suggesting that neural representations of mixtures are not simple combinations of the representations of the components. We studied odor responses to binary mixtures of amino acids and food extracts at different processing stages in the olfactory bulb (OB) of zebrafish. Odor-evoked input to the OB was measured by imaging Ca2+ signals in afferents to olfactory glomeruli. Activity patterns evoked by mixtures were predictable within narrow limits from the component patterns, indicating that mixture interactions in the peripheral olfactory system are weak. OB output neurons, the mitral cells (MCs), were recorded extra- and intracellularly and responded to odors with stimulus-dependent temporal firing rate modulations. Responses to mixtures of amino acids often were dominated by one of the component responses. Responses to mixtures of food extracts, in contrast, were more distinct from both component responses. These results show that mixture interactions can result from processing in the OB. Moreover, our data indicate that mixture interactions in the OB become more pronounced with increasing overlap of input activity patterns evoked by the components. Emerging from these results are rules of mixture interactions that may explain behavioral data and provide a basis for understanding the processing of natural odor stimuli in the OB. PMID:15269273

  12. Odorant binding proteins: a biotechnological tool for odour control.

    PubMed

    Silva, Carla; Matamá, Teresa; Azoia, Nuno G; Mansilha, Catarina; Casal, Margarida; Cavaco-Paulo, Artur

    2014-04-01

    The application of an odorant binding protein for odour control and fragrance delayed release from a textile surface was first explored in this work. Pig OBP-1 gene was cloned and expressed in Escherichia coli, and the purified protein was biochemically characterized. The IC₅₀ values (concentrations of competitor that caused a decay of fluorescence to half-maximal intensity) were determined for four distinct fragrances, namely, citronellol, benzyl benzoate, citronellyl valerate and ethyl valerate. The results showed a strong binding of citronellyl valerate, citronellol and benzyl benzoate to the recombinant protein, while ethyl valerate displayed weaker binding. Cationized cotton substrates were coated with porcine odorant binding protein and tested for their capacity to retain citronellol and to mask the smell of cigarette smoke. The immobilized protein delayed the release of citronellol when compared to the untreated cotton. According to a blind evaluation of 30 assessors, the smell of cigarette smoke, trapped onto the fabrics' surface, was successfully attenuated by porcine odorant binding protein (more than 60 % identified the weakest smell intensity after protein exposure compared to β-cyclodextrin-treated and untreated cotton fabrics). This work demonstrated that porcine odorant binding protein can be an efficient solution to prevent and/or remove unpleasant odours trapped on the large surface of textiles. Its intrinsic properties make odorant binding proteins excellent candidates for controlled release systems which constitute a new application for this class of proteins. PMID:24092006

  13. The role of piriform associative connections in odor categorization.

    PubMed

    Bao, Xiaojun; Raguet, Louise Lg; Cole, Sydni M; Howard, James D; Gottfried, Jay

    2016-01-01

    Distributed neural activity patterns are widely proposed to underlie object identification and categorization in the brain. In the olfactory domain, pattern-based representations of odor objects are encoded in piriform cortex. This region receives both afferent and associative inputs, though their relative contributions to odor perception are poorly understood. Here, we combined a placebo-controlled pharmacological fMRI paradigm with multivariate pattern analyses to test the role of associative connections in sustaining olfactory categorical representations. Administration of baclofen, a GABA(B) agonist known to attenuate piriform associative inputs, interfered with within-category pattern separation in piriform cortex, and the magnitude of this drug-induced change predicted perceptual alterations in fine-odor discrimination performance. Comparatively, baclofen reduced pattern separation between odor categories in orbitofrontal cortex, and impeded within-category generalization in hippocampus. Our findings suggest that odor categorization is a dynamic process concurrently engaging stimulus discrimination and generalization at different stages of olfactory information processing, and highlight the importance of associative networks in maintaining categorical boundaries. PMID:27130519

  14. Investigating a persistent odor at an aircraft seat manufacturer.

    PubMed

    Broadwater, Kendra; de Perio, Marie A; Roberts, Jennifer; Burton, Nancy C; Lemons, Angela R; Green, Brett J; Brueck, Scott E

    2016-10-01

    An aircraft seat manufacturing company requested a NIOSH health hazard evaluation to help identify a strong odor that had persisted throughout the facility for over a year. Employees reported experiencing health effects thought to be related to the odor. We collected and analyzed area air samples for volatile organic compounds, endotoxin, bacterial and fungal metagenome, and metalworking fluid aerosol. Bulk metalworking fluid samples were analyzed for endotoxin, bacterial and fungal metagenome, and viable bacteria and fungus. We also evaluated the building ventilation systems and water diversion systems. Employees underwent confidential medical interviews about work practices, medical history, and health concerns. Based on our analyses, the odor was likely 2-methoxy-3,5-dimethylpyrazine. This pyrazine was found in air samples across the facility and originated from bacteria in the metalworking fluid. We did not identify bacteria known to produce the compound but bacteria from the same Proteobacteria order were found as well as bacteria from orders known to produce other pyrazines. Chemical and biological contaminants and odors could have contributed to health symptoms reported by employees, but it is likely that the symptoms were caused by several factors. We provided several recommendations to eliminate the odor including washing and disinfecting the metalworking machines and metalworking fluid recycling equipment, discarding all used metalworking fluid, instituting a metalworking fluid maintenance program at the site, and physically isolating the metalworking department from other departments. PMID:27494786

  15. Rapid Odor Processing in the Honeybee Antennal Lobe Network

    PubMed Central

    Krofczik, Sabine; Menzel, Randolf; Nawrot, Martin P.

    2008-01-01

    In their natural environment, many insects need to identify and evaluate behaviorally relevant odorants on a rich and dynamic olfactory background. Behavioral studies have demonstrated that bees recognize learned odors within <200 ms, indicating a rapid processing of olfactory input in the sensory pathway. We studied the role of the honeybee antennal lobe network in constructing a fast and reliable code of odor identity using in vivo intracellular recordings of individual projection neurons (PNs) and local interneurons (LNs). We found a complementary ensemble code where odor identity is encoded in the spatio-temporal pattern of response latencies as well as in the pattern of activated and inactivated PN firing. This coding scheme rapidly reaches a stable representation within 50–150 ms after stimulus onset. Testing an odor mixture versus its individual compounds revealed different representations in the two morphologically distinct types of lateral- and median PNs (l- and m-PNs). Individual m-PNs mixture responses were dominated by the most effective compound (elemental representation) whereas l-PNs showed suppressed responses to the mixture but not to its individual compounds (synthetic representation). The onset of inhibition in the membrane potential of l-PNs coincided with the responses of putative inhibitory interneurons that responded significantly faster than PNs. Taken together, our results suggest that processing within the LN network of the AL is an essential component of constructing the antennal lobe population code. PMID:19221584

  16. The role of piriform associative connections in odor categorization

    PubMed Central

    Bao, Xiaojun; Raguet, Louise LG; Cole, Sydni M; Howard, James D; Gottfried, Jay A

    2016-01-01

    Distributed neural activity patterns are widely proposed to underlie object identification and categorization in the brain. In the olfactory domain, pattern-based representations of odor objects are encoded in piriform cortex. This region receives both afferent and associative inputs, though their relative contributions to odor perception are poorly understood. Here, we combined a placebo-controlled pharmacological fMRI paradigm with multivariate pattern analyses to test the role of associative connections in sustaining olfactory categorical representations. Administration of baclofen, a GABA(B) agonist known to attenuate piriform associative inputs, interfered with within-category pattern separation in piriform cortex, and the magnitude of this drug-induced change predicted perceptual alterations in fine-odor discrimination performance. Comparatively, baclofen reduced pattern separation between odor categories in orbitofrontal cortex, and impeded within-category generalization in hippocampus. Our findings suggest that odor categorization is a dynamic process concurrently engaging stimulus discrimination and generalization at different stages of olfactory information processing, and highlight the importance of associative networks in maintaining categorical boundaries. DOI: http://dx.doi.org/10.7554/eLife.13732.001 PMID:27130519

  17. Macroglomeruli for fruit odors change blend preference in Drosophila

    NASA Astrophysics Data System (ADS)

    Ibba, Irene; Angioy, Anna Maria; Hansson, Bill S.; Dekker, Teun

    2010-12-01

    The olfactory circuitry of Drosophila melanogaster is becoming increasingly clear. However, how olfactory processing translates into appropriate behavioral responses is still poorly understood. Using a sibling species approach, we tested how a perturbation in the olfactory circuitry affects odor preference. In a previous study, we found that the sibling species of D. melanogaster, the specialist D. sechellia, overrepresents a sensillum, ab3, the A neuron of which is sensitive to hexanoate esters, characteristic of the species' sole host, the Morinda citrifolia fruit. Concordantly, the corresponding glomerulus, DM2, is enlarged. In this study, we found that the ab3B neuron, the expansion of which was previously assumed to be pleiotropic and of no ecological significance, is in fact tuned to another morinda fruit volatile, 2-heptanone (HP). Axons of this neuron type arborize in a second enlarged glomerulus. In behavioral experiments we tested how this has affected the fly's odor preference. We demonstrate that D. sechellia has a reversed preference for the key ligands of these macroglomeruli, especially at high concentrations. Whereas D. melanogaster was repelled by high concentrations of these odors, D. sechellia was highly attracted. This was the case for odors presented singly, but more notably for blends thereof. Our study indicates that relatively simple changes, such as a shift in sensillar abundance, and concordant shifts in glomerular size, can distort the resulting olfactory code, and can lead to saltatory shifts in odor preference. D. sechellia has exploited this to align its olfactory preference with its ecological niche.

  18. Nanocellulose-Zeolite Composite Films for Odor Elimination.

    PubMed

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

    2015-07-01

    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. PMID:26061093

  19. Green Infrastructure

    EPA Science Inventory

    Large paved surfaces keep rain from infiltrating the soil and recharging groundwater supplies. Alternatively, Green infrastructure uses natural processes to reduce and treat stormwater in place by soaking up and storing water. These systems provide many environmental, social, an...

  20. Code Green.

    ERIC Educational Resources Information Center

    McMinn, John

    2002-01-01

    Assesses the integrated approach to green design in the new Computer Science Building at Toronto's York University. The building design fulfills the university's demand to combine an energy efficient design with sustainability. Floor and site plans are included. (GR)

  1. Green Roofs

    SciTech Connect

    2004-08-01

    A New Technology Demonstration Publication Green roofs can improve the energy performance of federal buildings, help manage stormwater, reduce airborne emissions, and mitigate the effects of urban heat islands.

  2. Green Giant.

    ERIC Educational Resources Information Center

    Polo, Marco

    2003-01-01

    Details the design of the Bahen Centre for Information Technology at the University of Toronto, particularly its emphasis on "green," or sustainable, design. Includes floor plans and photographs. (EV)

  3. Performance of green waste biocovers for enhancing methane oxidation.

    PubMed

    Mei, Changgen; Yazdani, Ramin; Han, Byunghyun; Mostafid, M Erfan; Chanton, Jeff; VanderGheynst, Jean; Imhoff, Paul

    2015-05-01

    Green waste aged 2 and 24months, labeled "fresh" and "aged" green waste, respectively, were placed in biocover test cells and evaluated for their ability to oxidize methane (CH4) under high landfill gas loading over a 15-month testing period. These materials are less costly to produce than green waste compost, yet satisfied recommended respiration requirements for landfill compost covers. In field tests employing a novel gas tracer to correct for leakage, both green wastes oxidized CH4 at high rates during the first few months of operation - 140 and 200g/m(2)/day for aged and fresh green waste, respectively. Biocover performance degraded during the winter and spring, with significant CH4 generated from anaerobic regions in the 60-80cm thick biocovers. Concurrently, CH4 oxidation rates decreased. Two previously developed empirical models for moisture and temperature dependency of CH4 oxidation in soils were used to test their applicability to green waste. Models accounted for 68% and 79% of the observed seasonal variations in CH4 oxidation rates for aged green waste. Neither model could describe similar seasonal changes for the less stable fresh green waste. This is the first field application and evaluation of these empirical models using media with high organic matter. Given the difficulty of preventing undesired CH4 generation, green waste may not be a viable biocover material for many climates and landfill conditions. PMID:25792440

  4. Evaluation of the active odorants in Amontillado sherry wines during the aging process.

    PubMed

    Moyano, Lourdes; Zea, Luis; Moreno, Jose A; Medina, Manuel

    2010-06-01

    Odor compounds in Amontillado sherry white wine obtained by means of biological aging first and oxidative aging second in American oak casks were determined by gas chromatography-olfactometry. Sniffing revealed fruity, fatty, chemical, spicy, vegetable, floral and empyreumatic odors, the first being the most common. Olfactometric intensity was assessed on a four-point scale. Most changes were detected during the first years of the oxidative aging step. Ethyl isobutanoate, ethyl butanoate, ethyl octanoate, and eugenol were the strongest odor compounds detected by sniffing in wines. The odor spectrum values for all active odorants were calculated in relation to ethyl octanoate, this compound being the most potent odorant. On the basis of olfactometric intensities and odor spectrum values, ethyl octanoate, ethyl butanoate, eugenol, ethyl isobutanoate, and sotolon can be deemed the main group of potent odorants in Amontillado wines. These compounds maintained similar relative contributions to the aroma profile during the oxidative aging step. PMID:20465212

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

    PubMed Central

    Gao, Xiang; Acar, Levent

    2016-01-01

    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. PMID:27384568

  6. A Time-Based Account of the Perception of Odor Objects and Valences

    PubMed Central

    Olofsson, Jonas K.; Bowman, Nicholas E.; Khatibi, Katherine; Gottfried, Jay A.

    2013-01-01

    Is human odor perception guided by memory or emotion? Object-centered accounts predict that recognition of unique odor qualities precedes valence decoding. Valence-centered accounts predict the opposite: that stimulus-driven valence responses precede and guide identification. In a speeded response time study, participants smelled paired odors, presented sequentially, and indicated whether the second odor in each pair belonged to the same category as the first (object evaluation task) or whether the second odor was more pleasant than the first (valence evaluation task). Object evaluation was faster and more accurate than valence evaluation. In a complementary experiment, participants performed an identification task, in which they indicated whether an odor matched the previously presented word label. Responses were quicker for odors preceded by semantically matching, rather than nonmatching, word labels, but results showed no evidence of interference from valence on nonmatching trials. These results are in accordance with object-centered accounts of odor perception. PMID:22961773

  7. A Review of Cyanobacterial Odorous and Bioactive Metabolites: Impacts and Management Alternatives in Aquaculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An increased demand has pushed extensive aquaculture towards intensively operated production systems, commonly resulting in eutrophic conditions and cyanobacterial blooms. This review summarizes cyanobacterial secondary metabolites that can cause undesirable tastes and odors (odorous metabolites) o...

  8. Influence of Ambient Odors on Time Perception in a Retrospective Paradigm.

    PubMed

    Brand, Gérard; Thiabaud, F; Dray, N

    2016-06-01

    Environmental stimuli can influence time perception, including sensory stimulations. Among them, odors are known to modulate emotion, attention, behavior, or performance, but few studies have investigated the possible effects of ambient odors on time perception. Thus, the present study aimed to compare in a retrospective paradigm the time estimation in three conditions, i.e., with phenyl ethyl alcohol as a pleasant odor, pyridine as unpleasant odor, and a control condition without ambient odor. A total of 90 participants (M age = 23 years, 10 months) took part in three different tasks, i.e., an aesthetic classification task, a sensorimotor checking task, and a mathematical operations task. Results showed a better accuracy of the time estimation in odor condition (1) independently of the characteristics of odorants (2) limited to tasks with a low cognitive involvement. These findings are discussed in relation to the possible role of attention and arousal in the modulation of time perception by ambient odors. PMID:27194618

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

    PubMed

    Gao, Xiang; Acar, Levent

    2016-01-01

    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. PMID:27384568

  10. Comparison of CALPUFF and ISCST3 models for predicting downwind odor and source emission rates

    NASA Astrophysics Data System (ADS)

    Wang, Lingjuan; Parker, David B.; Parnell, Calvin B.; Lacey, Ronald E.; Shaw, Bryan W.

    CALPUFF model and ISCST3 Gaussian dispersion models were evaluated for predicting downwind odor concentrations and back-calculating area source odor emission rates. The comparison between the predicted and field-sampled downwind concentrations indicates that the CALPUFF model could fairly well predict average downwind odor concentrations. However, ISCST3 tended to under predict downwind odor concentrations as compared to the measured concentrations. Both the CALPUFF and ISCST3 models failed to predict peak odor concentrations using the constant average emission rate. Odor emission rates obtained by back-calculating fluxes using CALPUFF and ISC models with the same field measurements of downwind odor concentrations are significantly different. It indicates that back-calculated emission rates are model specific. The modeled emission rates tended to be higher than flux chamber source sampling results. The flux chamber protocol may under-estimate odor emission rates.

  11. Musty odor of entomopathogens enhances disease-prevention behaviors in the termite Coptotermes formosanus.

    PubMed

    Yanagawa, Aya; Fujiwara-Tsujii, Nao; Akino, Toshiharu; Yoshimura, Tsuyoshi; Yanagawa, Takashi; Shimizu, Susumu

    2011-09-01

    Termites often eliminate pathogens directly through mutual grooming, and are thereby prevent infections from entomopathogenic fungi. Our previous study confirmed that the antennae of Coptotermesformosanus sensitively responded to the musty odor of entomopathogenic fungi. However, it is unclear if this odor has any effect on termite behavior. The purpose of this study was to clarify the effects of fungal odor on termite behavior, especially on conidia removal. The musty odor was prepared as an aqueous solution by immersing conidia in distilled water. When untreated termites were mixed with fungal-odor-treated termites at a ratio of 4:1, mutual grooming and attack of treated termites were frequently observed. This indicated that the fungal odor triggered these behavioral responses. While some components of the fungal odor were found in all of the entomopathogenic fungi tested, the odor profiles differed among the isolates. PMID:21683707

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

    PubMed Central

    Rice, Somchai; Koziel, Jacek A.

    2015-01-01

    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]. PMID:26958621

  13. Photoperiod and gonadal hormones influence odor preferences of the male meadow vole, Microtus pennsylvanicus.

    PubMed

    Ferkin, M H; Gorman, M R

    1992-05-01

    Male meadow voles housed in a long photoperiod (14 h light/day, LP) preferred female to male odors, whereas males maintained in a short photoperiod (10 h light/day, SP) did not display preferences for odors of either sex. These odor-preference patterns matched those of free-living males during spring and autumn, respectively. The preference of LP male voles for female over male odors was eliminated by gonadectomy and reinstated by treatment with testosterone. In SP males, although gonadectomy did not affect odor choices, a preference for female odors was induced by testosterone treatment. Treatment with estradiol did not alter odor preferences of LP or SP males. In conjunction with previous result, the present findings suggest that hormonal responsiveness of neural substrates that control odor preferences are sexually dimorphic and may reflect sex differences in reproductive strategies. PMID:1615048

  14. Mammalian Odor Information Recognition by Implanted Microsensor Array in vivo

    NASA Astrophysics Data System (ADS)

    Zhou, Jun; Dong, Qi; Zhuang, Liujing; Liu, Qingjun; Wang, Ping

    2011-09-01

    The mammalian olfactory system has an exquisite capacity to rapidly recognize and discriminate thousands of distinct odors in our environment. Our research group focus on reading information from olfactory bulb circuit of anethetized Sprague-Dawley rat and utilize artificial recognition system for odor discrimination. After being stimulated by three odors with concentration of 10 μM to rat nose, the response of mitral cells in olfactory bulb is recorded by eight channel microwire sensor array. In 20 sessions with 3 animals, we obtained 30 discriminated individual cells recordings. The average firing rates of the cells are Isoamyl acetate 26 Hz, Methoxybenzene 16 Hz, and Rose essential oil 11 Hz. By spike sorting, we detect peaks and analyze the interspike interval distribution. Further more, principal component analysis is applied to reduce the dimensionality of the data sets and classify the response.

  15. Differential odor processing in two olfactory pathways in the honeybee.

    PubMed

    Yamagata, Nobuhiro; Schmuker, Michael; Szyszka, Paul; Mizunami, Makoto; Menzel, Randolf

    2009-01-01

    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. PMID:20198105

  16. Odor quality: discrimination versus free and cued identification.

    PubMed

    de Wijk, R A; Cain, W S

    1994-07-01

    Eighty-two adults, ranging in age from young to elderly, performed odor-quality discrimination and both free and cued identification on six odorants presented at two intensity levels. The odorants simulated the real-world substances banana, licorice, cherry/almond, wintergreen, clove, and lemon. Performance on all three tasks declined with age, but improved with stimulus intensity. Performance at discrimination benefited from the mere availability of the six names during testing. Performance in cued identification far exceeded that in free identification and, for young and middle-aged adults, fell close to that for discrimination. For elderly adults, however, performance in cued identification fell substantially below that in discrimination. Although not entirely free of cognitive influences, discrimination seems to offer particularly clear resolution of alterations in olfactory functioning. PMID:8084728

  17. Nested expression domains for odorant receptors in zebrafish olfactory epithelium.

    PubMed

    Weth, F; Nadler, W; Korsching, S

    1996-11-12

    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. PMID:8917589

  18. Intensity invariant dynamics and odor-specific latencies in olfactory receptor neuron response

    PubMed Central

    Martelli, Carlotta; Carlson, John R.; Emonet, Thierry

    2013-01-01

    Odors elicit spatio-temporal patterns of activity in the brain. Spatial patterns arise from the specificity of the interaction between odorants and odorant receptors expressed in different olfactory receptor neurons (ORNs). But the origin of temporal patterns of activity and their role in odor coding remain unclear. We investigate how physiological aspects of ORN response and physical aspects of odor stimuli give rise to diverse responses in Drosophila ORNs. We show that odor stimuli have intrinsic dynamics that depend on odor type and strongly affect ORN response. Using linear-nonlinear modeling to remove the contribution of the stimulus dynamics from the ORN dynamics we study the physiological properties of the response to different odorants and concentrations. For several odorants and receptor types the ORN response dynamics normalized by the peak response are independent of stimulus intensity for a large portion of the neuron’s dynamic range. Adaptation to a background odor changes the gain and dynamic range of the response but does not affect normalized response dynamics. Stimulating ORNs with various odorants reveals significant odor-dependent delays in the ORN response functions. These differences however can be dominated by differences in stimulus dynamics. In one case the response of one ORN to two odorants is predicted solely from measurements of the odor signals. Within a large portion of their dynamic range ORNs can capture information about stimulus dynamics independently from intensity while introducing odor-dependent delays. How insects might use odor-specific stimulus dynamics and ORN dynamics in discrimination and navigation tasks remains an open question. PMID:23575828

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

    ERIC Educational Resources Information Center

    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…

  20. Evaluation of the Effectiveness of Five Odor Reducing Agents for Sewer System Odors Using an On-Line Total Reduced Sulfur Analyzer

    PubMed Central

    Choi, Il; Lee, Hyunjoo; Shin, Joungdu; Kim, Hyunook

    2012-01-01

    Sewer odors have been a concern to citizens of the Metropolitan Seoul region, which has installed combined sewer systems (CSSs) in 86% of its area. Although a variety of odorants are released from sewers, volatile sulfur compounds (VSCs) have been recognized as major ones. A number of technologies have been proposed to monitor or control odors from sewers. One of the most popular strategies adopted for the control of sewage odor is by applying a commercial odor-reducing agent into the sewer. In this study, the effectiveness of five different commercial odor-reducing agents (i.e., an odor masking agent, an alkaline solution, two microbial agents, and a chemical oxidant) was evaluated by continuously monitoring VSCs released from the sewer with an on-line total reduced sulfur (TRS) analyzer before and after each agent was sprayed into CSSs at five different locations of the city. In short, when the effectiveness of odor treatment was tested in the sewer system using five commercial odor reducing treatments, only the chemical oxidant was good enough to reduce the odor in terms of TRS levels measured before and after the application (p < 0.01). PMID:23223148

  1. The Green of Green Functions

    NASA Astrophysics Data System (ADS)

    Challis, Lawrie; Sheard, Fred

    2003-12-01

    In 1828, an English miller from Nottingham published a mathematical essay that generated little response. George Green's analysis, however, has since found applications in areas ranging from classical electrostatics to modern quantum field theory.

  2. Structure-Odor Activity Studies on Monoterpenoid Mercaptans Synthesized by Changing the Structural Motifs of the Key Food Odorant 1-p-Menthene-8-thiol.

    PubMed

    Schoenauer, Sebastian; Schieberle, Peter

    2016-05-18

    1-p-Menthene-8-thiol (1) has been discovered as the key odorant in grapefruit juice several decades ago and contributes to the overall odor of the fruit with an extremely low odor threshold of 0.000034 ng/L in air. This value is among the lowest odor thresholds ever reported for a food odorant. To check whether modifications in the structure of 1 would lead to changes in odor threshold and odor quality, 34 mercapto-containing p-menthane and 1-p-menthene derivatives as well as several aromatic and open-chain mercapto monoterpenoids were synthesized. Eighteen of them are reported for the first time in the literature, and their odor thresholds and odor qualities as well as analytical data are supplied. A comparison of the sensory data with those of 1 showed that hydrogenation of the double bond led to a clear increase in the odor threshold. Furthermore, moving the mercapto group into the ring always resulted in higher odor thresholds compared to thiols with a mercapto group in the side chains. Although all tertiary thiols always exhibited low odor thresholds, none of the 31 compounds reached the extremely low threshold of 1. Also, none of the synthesized mercapto monoterpenoids showed a similar odor quality resembling grapefruit. Although the saturated and aromatic analogues exhibited similar scents as 1, the aromas of the majority of the other compounds were described as sulfury, rubber-like, burned, soapy, or even mushroom-like. NMR and MS data as well as retention indices of the 23 newly reported sulfur-containing compounds might aid in future research to identify terpene-derived mercaptans possibly present in trace levels in foods. PMID:27121638

  3. Estimating dry matter content of fresh leaves from residuals between leaf and water reflectance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    At 1722 nm wavelength, there is an absorption feature of leaf dry matter based on a C—H stretch overtone, which is difficult to detect in fresh green leaves due to the absorption spectrum of liquid water. We applied a method originally proposed by B. -C. Gao and A. F. H. Goetz (1994, Remote Sensing ...

  4. A rare case of fish odor syndrome presenting as depression

    PubMed Central

    Khan, Shahbaz Ali; Shagufta, K.

    2014-01-01

    A young lady presents to the psychiatry out-patient department with depressive symptoms. Evaluation revealed long standing stressor in the form of a foul odor emanating from her body and over a period of time resulting in social withdrawal and depression with significant impairment of day-to-day functioning. A diagnosis of trimethylaminurea (fish odor syndrome) and adjustment disorder was arrived at. Careful empathetic handling with psychoeducation, behavioral and cognitive counseling and a short course of antidepressants helped her improve significantly with return to almost normal functioning. PMID:24891709

  5. Earthy odor compounds production and loss in three cyanobacterial cultures.

    PubMed

    Li, Zonglai; Hobson, Peter; An, Wei; Burch, Michael D; House, Jenny; Yang, Min

    2012-10-15

    Geosmin and 2-methylisoborneol (MIB) related odor events caused by cyanobacteria have been a very common problem to water supply. This paper investigated the effects of temperature (18 and 25 °C) and light intensity (10 and 100 μmol photons m(-2) s(-1)) on the production behaviors of earthy odor compounds by three odorous cyanobacteria, i.e., the geosmin-producing planktonic Anabaena circinalis (Ana 318), geosmin-producing benthic Phormidium amoenum (Pho 012) and MIB-producing benthic Phormidium sp. (Pho 689). At the same time, the effects of biodegradation and volatilization on the fates of the released odor compounds in water were also evaluated. The combination of high temperature (25 °C) and light intensity (100 μmol photons m(-2) s(-1)) favored the growth of the three cyanobacteria and the production of chl-a and odor compounds. However, higher chl-a and odor yields (average odor compounds per cell) were achieved for the two benthic cyanobacteria at the temperature of 18 °C. Most of geosmin was included within the cells for Ana 318 (95-99%) and Pho 012 (85-60%), while only 20-40% MIB was bound to the cells for Pho 689. The half-life times of MIB and geosmin due to volatilization varied between 18.8 and 35.4 days, while 8 out of 10 samples exhibited a half-life time (t(1/2)) for geosmin biodegradation shorter than 1 day (0.38-15.0 h), showing that biodegradation could affect the fate of geosmin significantly in aquatic environments. In comparison, biodegradation of MIB was much slower (t(1/2): 122-2166 h). Denaturing gradient gel electrophoresis (DGGE) analysis showed that Pseudomonas- and Sphingomonas-like bacteria coexisted with cyanobacteria in the cultures, and may have played an important role in geosmin/MIB biodegradation. The result of this study will be helpful for better understanding and managing the earthy odor problems caused by cyanobacteria in water supply. PMID:22818951

  6. Computational modeling and experimental validation of odor detection behaviours of classically conditioned parasitic wasp, Microplitis croceipes.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To further improve the sensitivity of odor¬ and odor concentration detection of the Wasp Hound, searching behaviors of a food-conditioned wasp in a confined area with the conditioning odor were recorded. The experiments were recorded using a video camera. First, the wasps are individually hand condi...

  7. Retronasal odor concentration coding in glomeruli of the rat olfactory bulb

    PubMed Central

    Gautam, Shree Hari; Short, Shaina M.; Verhagen, Justus V.

    2014-01-01

    The mammalian olfactory system processes odorants presented orthonasally (inhalation through the nose) and also retronasally (exhalation), enabling identification of both external as well as internal objects during food consumption. There are distinct differences between ortho- and retronasal air flow patterns, psychophysics, multimodal integration, and glomerular responses. Recent work indicates that rats can also detect odors retronasally, that rats can associate retronasal odors with tastes, and that their olfactory bulbs (OBs) can respond to retronasal odorants but differently than to orthonasal odors. To further characterize retronasal OB input activity patterns, experiments here focus on determining the effects of odor concentration on glomerular activity by monitoring calcium activity in the dorsal OB of rats using a dextran-conjugated calcium-sensitive dye in vivo. Results showed reliable concentration-response curves that differed between odorants, and recruitment of additional glomeruli, as odor concentration increased. We found evidence of different concentration-response functions between glomeruli, that in turn depended on odor. Further, the relation between dynamics and concentration differed remarkably among retronasal odorants. These dynamics are suggested to reduce the odor map ambiguity based on response amplitude. Elucidating the coding of retronasal odor intensity is fundamental to the understanding of feeding behavior and the neural basis of flavor. These data further establish and refine the rodent model of flavor neuroscience. PMID:25386123

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

    ERIC Educational Resources Information Center

    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…

  9. Effectiveness of a manure scraper system for odor control in tunnel-ventilated swine finisher barns

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Options for odor control from tunnel-ventilated swine barns are limited. Automated scrapers have been successful for reducing odor emissions in free-stall dairies, and for reducing H2S emissions in research-scale swine finisher rooms, but their effectiveness for reducing odor in commercial tunnel-v...

  10. High and low roads to odor valence? A choice response-time study.

    PubMed

    Olofsson, Jonas K; Bowman, Nicholas E; Gottfried, Jay A

    2013-10-01

    Valence and edibility are two important features of olfactory perception, but it remains unclear how they are read out from an olfactory input. For a given odor object (e.g., the smell of rose or garlic), does perceptual identification of that object necessarily precede retrieval of information about its valence and edibility, or alternatively, are these processes independent? In the present study, we studied rapid, binary perceptual decisions regarding odor detection, object identity, valence, and edibility for a set of common odors. We found that decisions regarding odor-object identity were faster than decisions regarding odor valence or edibility, but slower than detection. Mediation analysis revealed that odor valence and edibility decision response times were predicted by a model in which odor-object identity served as a mediator along the perceptual pathway from detection to both valence and edibility. According to this model, odor valence is determined through both a "low road" that bypasses odor objects and a "high road" that utilizes odor-object information. Edibility evaluations are constrained to processing via the high road. The results outline a novel causal framework that explains how major perceptual features might be rapidly extracted from odors through engagement of odor objects early in the processing stream. PMID:23875569

  11. Reduced Pleasant Touch Appraisal in the Presence of a Disgusting Odor

    PubMed Central

    Croy, Ilona; Angelo, Silvia D'; Olausson, Håkan

    2014-01-01

    Objectives Odors are powerful emotional stimuli influencing mood, attention and behavior. Here we examined if odors change the perception of pleasant touch. In line with the warning function of the olfactory system, we proposed that especially unpleasant odors will reduce touch pleasantness, presumably through a disgust-related mechanism. Methods Forty-five healthy participants (mean age 23.3 +/− 3years SD, 24 females) were presented to slow (3 cm/s) and fast (30 cm/s) brush stroking delivered by a robot to the forearm. Touch pleasantness under the influence of an unpleasant odor (Civette, smelling like feces) and an intensity matched pleasant odor (Rose) was compared to an odorless control condition. In a pilot study with 30 participants (mean age 25.9 +/−6 years, 21 females), the odors were matched according to their intensity, and we studied the influence of disgust sensitivity on the perception of 4 different odor qualities. Results The unpleasant odor decreased touch pleasantness for both stroking velocities compared to the odorless control (p<0.005) whereas the rose odor did not change touch pleasantness significantly. Disgust sensitivity was correlated with the modulation of touch pleasantness. The pilot study revealed a significant correlation between disgust sensitivity and the perception of the unpleasant odor qualities (r = −0.56; p = 0.007), but not with any of the other odors. Conclusion Unpleasant odors are powerful in modulating touch pleasantness, and disgust might be a moderating variable. PMID:24664177

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

    ERIC Educational Resources Information Center

    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…

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

    ERIC Educational Resources Information Center

    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…

  14. Temporal resolution of general odor pulses by olfactory sensory neurons in American cockroaches

    PubMed

    Lemon; Getz

    1997-01-01

    Behavioral and physiological evidence indicates that insect pheromone sensory neurons are able to resolve pulses of pheromone concentration as they occur downwind from a point source, but the abilities of insect sensory neurons that are sensitive to general odors to respond to pulsatile stimuli are unknown. The temporal response characteristics of olfactory sensory neurons of female American cockroaches Periplaneta americana in response to general odors were measured using a series of short odor pulses (20­400 ms). Odor pulses were delivered to olfactory sensilla in a moving airstream controlled by electromagnetic valves. The responses of sensory neurons were recorded using a tungsten electrode placed at the base of the sensillum. The temporal responses of sensory neurons followed the temporal changes in stimulus concentration, which were estimated by replacing the odorant with oil smoke and measuring the concentration of smoke passing through a light beam. Spike frequency varied with odorant concentration with surprisingly fine temporal resolution. Cockroach olfactory sensory neurons were able reliably to follow 25 ms pulses of the pure odorant 1-hexanol and 50 ms pulses of the complex odor blend coconut oil. Lower concentrations of odorants elicited responses with lower peak spike frequencies that still retained the temporal resolution of the stimulus pulses. Thus, responses of olfactory sensory neurons can reflect the fine structures of non-uniform distributions of general odorants in a turbulent odor plume as well as the average odorant concentration. PMID:9319720

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

    EPA Science Inventory

    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...

  16. Electroantennogram (EAG) responses of Microplitis croceipes and Cotesia marginiventris and their lepidopteran hosts to a wide array of odor stimuli: correlation between EAG response and degree of host specificity?

    PubMed

    Ngumbi, Esther; Chen, Li; Fadamiro, Henry

    2010-09-01

    In order to test whether the electroantennogram (EAG) response spectrum of an insect correlates to its degree of host specificity, we recorded EAG responses of two parasitoid species with different degrees of host specificity, Microplitis croceipes (specialist) and Cotesia marginiventris (generalist), to a wide array of odor stimuli including compounds representing green leaf volatiles (GLVs), herbivore-induced plant volatiles (HIPV), ecologically irrelevant (not used by the parasitoid species and their hosts for host location) plant volatiles, and host-specific odor stimuli (host sex pheromones, and extracts of host caterpillar body and frass). We also tested the EAG responses of female moths of the caterpillar hosts of the parasitoids, Heliothis virescens and Spodoptera exigua, to some of the odor stimuli. We hypothesized that the specialist parasitoid will have a narrower EAG response spectrum than the generalist, and that the two lepidopteran species, which are similar in their host plant use, will show similar EAG response spectra to plant volatiles. As predicted, the specialist parasitoid showed greater EAG responses than the generalist to host-specific odor and one HIPV (cis-3-hexenyl butyrate), whereas the generalist showed relatively greater EAG responses to the GLVs and unrelated plant volatiles. We detected no differences in the EAG responses of H. virescens and S. exigua to any of the tested odor. PMID:20371248

  17. Characterization of the Key Aroma Volatile Compounds in Cranberry (Vaccinium macrocarpon Ait.) Using Gas Chromatography-Olfactometry (GC-O) and Odor Activity Value (OAV).

    PubMed

    Zhu, JianCai; Chen, Feng; Wang, LingYing; Niu, YunWei; Chen, HeXing; Wang, HongLin; Xiao, ZuoBing

    2016-06-22

    The volatile compounds of cranberries obtained from four cultivars (Early Black, Y1; Howes, Y2; Searles, Y3; and McFarlin, Y4) were analyzed by gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS), and GC-flame photometric detection (FPD). The result presented that a total of thirty-three, thirty-four, thirty-four, and thirty-six odor-active compounds were identified by GC-O in the Y1, Y2, Y3, and Y4, respectively. In addition, twenty-two, twenty-two, thirty, and twenty-seven quantified compounds were demonstrated as important odorants according to odor activity values (OAVs > 1). Among these compounds, hexanal (OAV: 27-60), pentanal (OAV: 31-51), (E)-2-heptenal (OAV: 17-66), (E)-2-hexenal (OAV: 18-63), (E)-2-octenal (OAV: 10-28), (E)-2-nonenal (OAV: 8-77), ethyl 2-methylbutyrate (OAV: 10-33), β-ionone (OAV: 8-73), 2-methylbutyric acid (OAV: 18-37), and octanal (OAV: 4-24) contributed greatly to the aroma of cranberry. Partial least-squares regression (PLSR) was used to process the mean data accumulated from sensory evaluation by the panelists, odor-active aroma compounds (OAVs > 1), and samples. Sample Y3 was highly correlated with the sensory descriptors "floral" and "fruity". Sample Y4 was greatly related to the sensory descriptors "mellow" and "green and grass". Finally, an aroma reconstitution (Model A) was prepared by mixing the odor-active aroma compounds (OAVs > 1) based on their measured concentrations in the Y1 sample, indicating that the aroma profile of the reconstitution was pretty similar to that of the original sample. PMID:27265519

  18. 21 CFR 101.95 - “Fresh,” “freshly frozen,” “fresh frozen,” “frozen fresh.”

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false âFresh,â âfreshly frozen,â âfresh frozen,â âfrozen fresh.â 101.95 Section 101.95 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION FOOD LABELING Specific Requirements...

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

    PubMed Central

    Degl'Innocenti, Andrea

    2016-01-01

    Background 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. Aim 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. Procedures 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. Results 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

  20. Odor attributes change in relation to the time of the year. Cinnamon odor is more familiar and pleasant during Christmas season than summertime.

    PubMed

    Seo, Han-Seok; Buschhüter, Dorothee; Hummel, Thomas

    2009-10-01

    Aim of the present study was to examine whether odor attributes like pleasantness and familiarity change in relation to the time of the year. In the first part of the study a total of 100 subjects answered to questions without odor presentation whether a certain odor was more related to summertime or Christmas season. Another 41 and 51 subjects rated the familiarity and hedonicity of 12 odors either during summertime or Christmas season, respectively. Importantly, this investigation was performed at the same place within a science museum during stable environmental conditions. Subjects reported that rose odor was more related to summertime, whereas orange, cinnamon, and cloves were more associated with Christmas season with cinnamon being most intimately connected to this time of the year. Moreover, subjects showed significantly higher familiarity and pleasantness ratings when they smelled cinnamon during the Christmas season than during summertime. Taken together, this study demonstrated that attributes of some odors change throughout the year. PMID:19576937

  1. Ozone inactivation of norovirus surrogates on fresh produce.

    PubMed

    Hirneisen, K A; Markland, S M; Kniel, K E

    2011-05-01

    Preharvest contamination of produce by foodborne viruses can occur through a variety of agents, including animal feces/manures, soil, irrigation water, animals, and human handling. Problems of contamination are magnified by potential countrywide distribution. Postharvest processing of produce can involve spraying, washing, or immersion into water with disinfectants; however, disinfectants, including chlorine, have varying effects on viruses and harmful by-products pose a concern. The use of ozone as a disinfectant in produce washes has shown great promise for bacterial pathogens, but limited research exists on its efficacy on viruses. This study compares ozone inactivation of human norovirus surrogates (feline calicivirus [FCV] and murine norovirus [MNV]) on produce (green onions and lettuce) and in sterile water. Green onions and lettuce inoculated with FCV or MNV were treated with ozone (6.25 ppm) for 0.5- to 10-min time intervals. Infectivity was determined by 50% tissue culture infectious dose (TCID(50)) and plaque assay for FCV and MNV, respectively. After 5 min of ozone treatment, >6 log TCID(50)/ml of FCV was inactivated in water and ∼2-log TCID(50)/ml on lettuce and green onions. MNV inoculated onto green onions and lettuce showed a >2-log reduction after 1 min of ozone treatment. The food matrix played the largest role in protection against ozone inactivation. These results indicate that ozone is an alternative method to reduce viral contamination on the surface of fresh produce. PMID:21549058

  2. Antimicrobial packaging for fresh-cut fruits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fresh-cut fruits are minimally processed produce which are consumed directly at their fresh stage without any further kill step. Microbiological quality and safety are major challenges to fresh-cut fruits. Antimicrobial packaging is one of the innovative food packaging systems that is able to kill o...

  3. Attachment and localization of human norovirus and animal caliciviruses in fresh produce.

    PubMed

    DiCaprio, Erin; Purgianto, Anastasia; Ma, Yuanmei; Hughes, John; Dai, Xiangjun; Li, Jianrong

    2015-10-15

    Fresh produce is a high risk food for human norovirus (NoV) contamination. To help control this pathogen in fresh produce, a better understanding of the interaction of human NoV and fresh produce needs to be established. In this study the attachment of human NoV and animal caliciviruses (murine norovirus, MNV-1; Tulane virus, TV) to fresh produce was evaluated, using both visualization and viral enumeration techniques. It was found that a human NoV GII.4 strain attached efficiently to the Romaine lettuce leaves and roots and green onion shoots, and that washing with PBS or 200 ppm of chlorine removed less than 0.4 log of viral RNA copies from the tissues. In contrast, TV and MNV-1 bound more efficiently to Romaine lettuce leaves than to the roots, and simple washing removed less than 1 log of viruses from the lettuce leaves and 1-4 log PFU of viruses from roots. Subsequently, the location of virus particles in fresh produce was visualized using a fluorescence-based Quantum Dots (Q-Dots) assay and confocal microscopy. It was found that human NoV virus-like particles (VLPs), TV, and MNV-1 associated with the surface of Romaine lettuce and were found aggregating in and around the stomata. In green onions, human NoV VLPs were found between the cells of the epidermis and cell walls of both the shoots and roots. However, TV and MNV-1 were found to be covering the surface of the epidermal cells in both the shoots and roots of green onions. Collectively, these results demonstrate that (i) washing with 200 ppm chlorine is ineffective in removing human NoV from fresh produce; and (ii) different viruses vary in their localization patterns to different varieties of fresh produce. PMID:26188496

  4. Testing Odor Response Stereotypy in the Drosophila Mushroom Body

    PubMed Central

    Murthy, Mala; Fiete, Ila; Laurent, Gilles

    2008-01-01

    SUMMARY The mushroom body is required for olfactory learning in flies. Its principal neurons, the Kenyon cells (KCs), form a large cell population, usually divided into three classes(α/β, α’/β’, and γ) based on anatomical criteria. Both neuronal populations from which their olfactory input derives, the projection neurons (PNs) and the presynaptic partners of the PNs, the olfactory sensory neurons, can be identified individually by their glomerular projections, the expression of specific genes, and their odor responses. We ask here whether KCs are similarly identifiable individually. We focused on a subset of ~23 genetically labeled α/β KCs, and recorded their responses to odors using whole-cell patch-clamp in vivo. Response profiles across this sample provided no evidence for repeats across animals. Further, across-animal responses were as diverse within the genetically-labeled subset as across all KCs in a larger sample. By contrast, recorded PN odor responses clustered by glomerular type. Using these PN responses as inputs to a simple KC model, we find that measured inter-fly PN response variability combined with stereotyped PN-to-KC connectivity cannot explain the absence of KC odor response stereotypy. These results suggest differences in PN-to-KC connectivity across individual flies. PMID:18817738

  5. Olfaction in petrels: from homing to self-odor avoidance.

    PubMed

    Bonadonna, Francesco

    2009-07-01

    In the 1960s, Betsy Bang unraveled the complexity of the olfactory apparatus of procellariiform seabirds (petrels and albatrosses), suggesting an important role for olfaction in their ecology. Shortly thereafter, Prof. B. Wenzel continued the investigations on petrels' well-developed olfactory neuroanatomy as well as their sensitivity to food-related scents. Later studies demonstrated further that the sense of smell is also critical to these birds when homing to their burrow. Building on these findings, we have demonstrated in several petrel species the importance of the burrow olfactory signature in homing. The nature of this olfactory signature relies predominantly on their mate's odor. Indeed, in our Y-maze experiments, Antarctic prions (Pachyptila desolata) and blue petrels (Halobaena caerulea) could discriminate between their own and their mates' odors. However, although they are attracted by their mate odor, they prefer the odor of a conspecific bird to their own. These results have drawn attention to the possible use of chemical signals in birds' social behaviors, such as individual recognition and/or mate choice. Indeed, petrel life history traits suggest that olfactory-mediated mate choice may have evolved in this group to ensure genetic compatibility between mates. We have recently shown that a bird's semiochemical profile is more similar to itself, year after year, than to that of a conspecific. As a result, a novel function of olfaction emerges in petrels: the perception of a chemical signal that may broadcast individuals' identity and quality, thereby contributing to an optimal mate choice. PMID:19686171

  6. Odorant-binding proteins from a primitive termite.

    PubMed

    Ishida, Yuko; Chiang, Vicky P; Haverty, Michael I; Leal, Walter S

    2002-09-01

    Hitherto, odorant-binding proteins (OBPs) have been identified from insects belonging to more highly evolved insect orders (Lepidoptera, Coleoptera, Diptera, Hymenoptera, and Hemiptera), whereas only chemosensory proteins have been identified from more primitive species, such as orthopteran and phasmid species. Here, we report for the first time the isolation and cloning of odorant-binding proteins from a primitive termite species, the dampwood termite. Zootermopsis nevadensis nevadensis (Isoptera: Termopsidae). A major antennae-specific protein was detected by native PAGE along with four other minor proteins, which were also absent in the extract from control tissues (hindlegs). Multiple cDNA cloning led to the full characterization of the major antennae-specific protein (ZnevOBP1) and to the identification of two other antennae-specific cDNAs, encoding putative odorant-binding proteins (ZnevOBP2 and ZnevOBP3). N-terminal amino acid sequencing of the minor antennal bands and cDNA cloning showed that olfaction in Z. n. nevadensis may involve multiple odorant-binding proteins. Database searches suggest that the OBPs from this primitive termite are homologues of the pheromone-binding proteins from scarab beetles and antennal-binding proteins from moths. PMID:12449514

  7. Transitivity of Odor Preferences: Constant and Particularities in Hedonic Perception

    ERIC Educational Resources Information Center

    Brand, Gerard; Haaz, Virginie; Jacquot, Laurence

    2012-01-01

    Transitivity of preferences has been investigated for a long time in decision-making. In the field of perception, the pleasantness of odors raises several questions related to individual versus cultural or universal preferences and the existence of a classification in a delimited hedonic space. The aim of this study was to test transitivity in…

  8. Odor-associated idiopathic anaphylaxis. A case report.

    PubMed

    Saunders, R L; Halpern, G M; Gershwin, M E

    1995-01-01

    A 44 year old woman is described who appears to have idiopathic anaphylaxis triggered by chemical odors. Her case and a general discussion of anaphylaxis are presented. The known causes of anaphylaxis and a discourse on idiopathic anaphylaxis are given. The treatment of idiopathic anaphylaxis is discussed. PMID:7631593

  9. 46 CFR 193.15-17 - Odorizing units.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... carbon dioxide gas is present in a protected area and any other area into which the carbon dioxide may... 46 Shipping 7 2012-10-01 2012-10-01 false Odorizing units. 193.15-17 Section 193.15-17 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE...

  10. 46 CFR 95.15-60 - Odorizing units.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... is present in a protected area and any other area into which the carbon dioxide may migrate. “Altered... 46 Shipping 4 2013-10-01 2013-10-01 false Odorizing units. 95.15-60 Section 95.15-60 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE...

  11. 46 CFR 95.15-60 - Odorizing units.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... is present in a protected area and any other area into which the carbon dioxide may migrate. “Altered... 46 Shipping 4 2014-10-01 2014-10-01 false Odorizing units. 95.15-60 Section 95.15-60 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE...

  12. Odors and Air Pollution: A Bibliography with Abstracts.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Research Triangle Park, NC. Office of Air Programs.

    The annotated bibliography presents a compilation of abstracts which deal with odors as they relate to air pollution. The abstracts are arranged within the following categories: Emission sources; Control methods; Measurement methods; Air quality measurements; Atmospheric interaction; Basic science and technology; Effects-human health;…

  13. Odorous VOC emission following land application of swine manure slurry

    NASA Astrophysics Data System (ADS)

    Parker, David B.; Gilley, John; Woodbury, Bryan; Kim, Ki-Hyun; Galvin, Geordie; Bartelt-Hunt, Shannon L.; Li, Xu; Snow, Daniel D.

    2013-02-01

    Swine manure is often applied to crop land as a fertilizer source. Odor emissions from land-applied swine manure may pose a nuisance to downwind populations if manure is not applied with sufficient forethought. A research project was conducted to assess the time decay of odorous volatile organic compound (VOC) emissions following land application of swine manure. Three land application methods were compared: surface application, incorporation 24 h after surface application, and injection. Emission rates were measured in field plots using a small wind tunnel and sorbent tubes. VOCs including eight volatile fatty acids, five aromatics, and two sulfur-containing compounds were quantified by gas chromatography-mass spectrometry. In most cases, a first order exponential decay model adequately described the flux versus time relationship for the 24 h period following land application, but the model sometimes overestimated flux in the 6-24 h range. The same model but with the time term squared adequately predicted flux over the entire 24 h period. Three compounds (4-methylphenol, skatole, and 4-ethylphenol) accounted for 93 percent of the summed odor activity value. First order decay constants (k) for these three compounds ranged from 0.157 to 0.996 h-1. When compared to surface application, injection of swine manure resulted in 80-95 percent lower flux for the most odorous aromatic compounds. These results show that VOC flux decreases rapidly following land application of swine manure, declining below levels of detection and near background levels after 4 to 8 h.

  14. Investigation of breathing parameters during odor perception and olfactory imagery.

    PubMed

    Kleemann, A M; Kopietz, R; Albrecht, J; Schöpf, V; Pollatos, O; Schreder, T; May, J; Linn, J; Brückmann, H; Wiesmann, M

    2009-01-01

    Compared with visual and auditory imagery, little is known about olfactory imagery. There is evidence that respiration may be altered by both olfactory perception and olfactory imagery. In order to investigate this relationship, breathing parameters (respiratory minute volume, respiratory amplitude, and breathing rate) in human subjects during olfactory perception and olfactory imagery were investigated. Fifty-six subjects having normal olfactory function were tested. Nasal respiration was measured using a respiratory pressure sensor. Using an experimental block design, we alternately presented odors or asked the subjects to imagine a given smell. Four different pleasant odors were used: banana, rose, coffee, and lemon odor. We detected a significant increase in respiratory minute volume between olfactory perception and the baseline condition as well as between olfactory imagery and baseline condition. Additionally we found significant differences in the respiratory amplitude between imagery and baseline condition and between odor and imagery condition. Differences in the breathing rate between olfactory perception, olfactory imagery, and baseline were not statistically significant. We conclude from our results that olfactory perception and olfactory imagery both have effects on the human respiratory profile and that these effects are based on a common underlying mechanism. PMID:18701432

  15. Field sampling method for quantifying odorants in humid environments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most air quality studies in agricultural environments typically use thermal desorption analysis for quantifying volatile organic compounds (VOC) associated with odor. Carbon molecular sieves (CMS) are popular sorbent materials used in these studies. However, there is little information on the effe...

  16. Chemotopic Representations of Aromatic Odorants in the Rat Olfactory Bulb

    PubMed Central

    Farahbod, Haleh; Johnson, Brett A.; Minami, S. Sakura; Leon, Michael

    2008-01-01

    Our laboratory has characterized spatial patterns of evoked neural activity across the entire glomerular layer of the rat olfactory bulb using primarily aliphatic odorants that differ systematically in functional groups and hydrocarbon structures. To represent more fully the true range of odorant chemistry, we have investigated aromatic compounds, which have a more rigid molecular structure than most aliphatic compounds and are particularly salient olfactory stimuli for humans. We first investigated glomerular patterns of 2-deoxyglucose uptake in response to aromatic compounds that differ in the nature and position of their functional groups (e.g., xylenes, trimethylbenzenes, tolualdehydes, benzaldehydes, methyl toluates, and anisaldehydes). We also studied the effects of systematic increases in the number and length of alkyl substituents. We found that most aromatic compounds activated glomeruli in the dorsal part of the bulb. Within this general area, aromatic odorants with oxygen-containing substituents favored activation of more rostral regions, and aromatic hydrocarbons activated more posterior regions. The nature of substituents greatly affected the pattern of glomerular activation, whereas isomers differing in substitution position evoked very similar overall patterns. These relationships between the structure of aromatic compounds and their spatial representation in the bulb are contrasted with our previous findings with aliphatic odorants. PMID:16736464

  17. Major Odorants Released as Urinary Volatiles by Urinary Incontinent Patients

    PubMed Central

    Pandey, Sudhir Kumar; Kim, Ki-Hyun; Choi, Si On; Sa, In Young; Oh, Soo Yeon

    2013-01-01

    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. PMID:23823973

  18. Developing livestock odor reduction system using biochar/hydrochar characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Malodorous emissions from livestock operations disrupt quality of life in rural and urban communities. The objective of this study is to characterize various biochars, both made from wet and dry pyrolysis of biomass, in terms of their potential capacity to be used as a sorbent for removing odorous c...

  19. Marijuana odor perception: studies modeled from probable cause cases.

    PubMed

    Doty, Richard L; Wudarski, Thomas; Marshall, David A; Hastings, Lloyd

    2004-04-01

    The 4th Amendment of the United States Constitution protects American citizens against unreasonable search and seizure without probable cause. Although law enforcement officials routinely rely solely on the sense of smell to justify probable cause when entering vehicles and dwellings to search for illicit drugs, the accuracy of their perception in this regard has rarely been questioned and, to our knowledge, never tested. In this paper, we present data from two empirical studies based upon actual legal cases in which the odor of marijuana was used as probable cause for search. In the first, we simulated a situation in which, during a routine traffic stop, the odor of packaged marijuana located in the trunk of an automobile was said to be detected through the driver's window. In the second, we investigated a report that marijuana odor was discernable from a considerable distance from the chimney effluence of diesel exhaust emanating from an illicit California grow room. Our findings suggest that the odor of marijuana was not reliably discernable by persons with an excellent sense of smell in either case. These studies are the first to examine the ability of humans to detect marijuana in simulated real-life situations encountered by law enforcement officials, and are particularly relevant to the issue of probable cause. PMID:15141780

  20. Evaluation of odors associated with land application of biosolids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An odor study was performed at a biosolids application demonstration site using several different gas collection devices and analytical methods to determine changes in air concentration of several organic and inorganic compounds associated with biosolids application over various time periods. Vario...

  1. 46 CFR 193.15-17 - Odorizing units.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-17 Odorizing units. Each carbon dioxide extinguishing system installed or altered after July 9, 2013, must have an approved... carbon dioxide gas is present in a protected area and any other area into which the carbon dioxide...

  2. 46 CFR 76.15-60 - Odorizing units.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-60 Odorizing units. Each carbon dioxide... the scent of wintergreen, the detection of which will serve as an indication that carbon dioxide gas is present in a protected area and any other area into which the carbon dioxide may migrate....

  3. 46 CFR 76.15-60 - Odorizing units.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-60 Odorizing units. Each carbon dioxide... the scent of wintergreen, the detection of which will serve as an indication that carbon dioxide gas is present in a protected area and any other area into which the carbon dioxide may migrate....

  4. 46 CFR 95.15-60 - Odorizing units.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-60 Odorizing units. Each carbon dioxide... the scent of wintergreen, the detection of which will serve as an indication that carbon dioxide gas is present in a protected area and any other area into which the carbon dioxide may migrate....

  5. 46 CFR 76.15-60 - Odorizing units.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-60 Odorizing units. Each carbon dioxide... the scent of wintergreen, the detection of which will serve as an indication that carbon dioxide gas is present in a protected area and any other area into which the carbon dioxide may migrate....

  6. Odor mitigation with vegetative buffers: Swine production case study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetative environmental buffers (VEB) are a potentially low cost sustainable odor mitigation strategy, but there is little to no data supporting their effectiveness. Wind tunnel experiments and field monitoring were used to determine the effect VEB had on wind flow patterns within a swine facility....

  7. Sniffing the Unique “Odor Print” of Non-Small-Cell Lung Cancer with Gold Nanoparticles

    PubMed Central

    Barash, Orna; Peled, Nir; Hirsch, Fred R.

    2012-01-01

    A highly sensitive and fast-response array of sensors based on gold nanoparticles, in combination with pattern recognition methods, can distinguish between the odor prints of non-small-cell lung cancer and negative controls with 100% accuracy, with no need for preconcentration techniques. Additionally, preliminary results indicate that the same array of sensors might serve as a better tool for understanding the biochemical source of volatile organic compounds that might occur in cancer cells and appear in the exhaled breath, as compared to traditional spectrometry techniques. The reported results provide a launching pad to initiate a bedside tool that might be able to screen for early stages of lung cancer and allow higher cure rates. In addition, such a tool might be used for the immediate diagnosis of fresh (frozen) tissues of lung cancer in operating rooms, where a dichotomic diagnosis is crucial to guide surgeons. PMID:19705367

  8. Fancy Citrus, Feel Good: Positive Judgment of Citrus Odor, but Not the Odor Itself, Is Associated with Elevated Mood during Experienced Helplessness.

    PubMed

    Hoenen, Matthias; Müller, Katharina; Pause, Bettina M; Lübke, Katrin T

    2016-01-01

    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 < 0.001), 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 = 0.019). 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. PMID:26869973

  9. Structure-odor correlations in homologous series of alkanethiols and attempts to predict odor thresholds by 3D-QSAR studies.

    PubMed

    Polster, Johannes; Schieberle, Peter

    2015-02-11

    Homologous series of alkane-1-thiols, alkane-2-thiols, alkane-3-thiols, 2-methylalkane-1-thiols, 2-methylalkane-3-thiols, 2-methylalkane-2-thiols, and alkane-1,ω-dithiols were synthesized to study the influence of structural changes on odor qualities and odor thresholds. In particular, the odor thresholds were strongly influenced by steric effects: In all homologous series a minimum was observed for thiols with five to seven carbon atoms, whereas increasing the chain length led to an exponential increase in the odor threshold. Tertiary alkanethiols revealed clearly lower odor thresholds than found for primary or secondary thiols, whereas neither a second mercapto group in the molecule nor an additional methyl substitution lowered the threshold. To investigate the impact of the SH group, odor thresholds and odor qualities of thiols were compared to those of the corresponding alcohols and (methylthio)alkanes. Replacement of the SH group by an OH group as well as S-methylation of the thiols significantly increased the odor thresholds. By using comparative molecular field analysis, a 3D quantitative structure-activity relationship model was created, which was able to simulate the odor thresholds of alkanethiols in good agreement with the experimental results. NMR and mass spectrometric data for 46 sulfur-containing compounds are additionally supplied. PMID:25608797

  10. Aroma profile of star anise and the structure-odor relationship of anethole.

    PubMed

    Hasegaw, Toshio; Seimiya, Haruna; Fujihara, Takashi; Fujiwara, Noriko; Yamada, Hideo

    2014-02-01

    Star anise is an important fragrance material that has a characteristic anise-like odor. Although the main component of star anise is (E)-anethole, which accounts for over 90% of the constituents, the odor of (E)-anethole is different from that of the material itself. Here, we examined the aroma profile of star anise. GC-MS analysis of star anise extracts showed that it contains many compounds with structures similar to (E)-anethole. Our results indicate that (E)-anethole is the key compound in the odor of star anise, but structurally similar compounds play an important role in creating its odor. We examined the structure-odor relationship of (E)-anethole, focusing on the methoxy and 1-propenyl substituents. Altering the 1-propenyl group changed the odors of all the anethole derivatives. Replacing the methoxy group with a hydrogen atom created compounds with similar fatty odors. This shows that the methoxy group is important for the characteristic odor of anethole. We synthesized anethole derivatives where the methoxy group was replaced with a methyl group. In both methoxy- and methyl-substituted anethole derivatives, altering the 1-propenyl group changed the odors of the derivatives. Therefore, the methoxy and methyl benzene moieties are important structural features for the odor of star anise. The structural characteristics of anethole are closely related to its odor expression. PMID:24689303

  11. Habituation of glomerular responses in the olfactory bulb following prolonged odor stimulation reflects reduced peripheral input

    PubMed Central

    Ogg, M. Cameron; Bendahamane, Mounir; Fletcher, Max L.

    2015-01-01

    Following prolonged odor stimulation, output from olfactory bulb (OB) mitral/tufted (M/T) cells is decreased in response to subsequent olfactory stimulation. Currently, it is unclear if this decrease is a function of adaptation of peripheral olfactory sensory neuron (OSN) responses or reflects depression of bulb circuits. We used wide-field calcium imaging in anesthetized transgenic GCaMP2 mice to compare excitatory glomerular layer odor responses before and after a 30-s odor stimulation. Significant habituation of subsequent glomerular odor responses to both the same and structurally similar odorants was detected with our protocol. To test whether depression of OSN terminals contributed to this habituation, olfactory nerve layer (ON) stimulation was used to drive glomerular layer responses in the absence of peripheral odor activation of the OSNs. Following odor habituation, in contrast to odor-evoked glomerular responses, ON stimulation-evoked glomerular responses were not habituated. The difference in response between odor and electrical stimulation following odor habituation provides evidence that odor response reductions measured in the glomerular layer of the OB are most likely the result of OSN adaptation processes taking place in the periphery. PMID:26441516

  12. Identification of candidate odorant receptors in Asian corn borer Ostrinia furnacalis.

    PubMed

    Yang, Bin; Ozaki, Katsuhisa; Ishikawa, Yukio; Matsuo, Takashi

    2015-01-01

    In lepidopteran insects, odorant receptors are involved in the perception of sex pheromones and general odorants. In the Asian corn borer, Ostrinia furnacalis, although several pheromone receptors have been identified, no general odorant receptor has been reported. In this study, an RNA sequencing analysis was carried out to identify the whole repertoire of the odorant receptors expressed in the antennae of O. furnacalis. Among 12 million reads obtained from the antennae of male and female moths, 52 candidate odorant receptors were identified, including 45 novel ones. Expression levels of candidate odorant receptors were estimated by read mapping and quantitative reverse transcription PCR. These analyses confirmed that the expression of the previously identified pheromone receptors was highly male biased. In contrast, none of the newly identified odorant receptors showed male-biased expression. Three of the newly identified odorant receptors showed female-biased expression. Two of them were the most highly expressed odorant receptors in the female antennae, suggesting that they may be involved in the detection of odorants important for the induction of female-specific behaviors such as oviposition site selection. In addition, candidate genes of 21 ionotropic receptors, 5 gustatory receptors, 2 sensory neuron membrane proteins, and 26 odorant degrading enzymes were identified. Our results provide a basis for further analysis of the chemosensory system in the Ostrinia species. PMID:25803580

  13. Hazardous and odorous pollutants released from sewer manholes and stormwater catch basins in urban areas.

    PubMed

    Pandey, Sudhir Kumar; Kim, Ki-Hyun; Kwon, Eilhann E; Kim, Yong-Hyun

    2016-04-01

    To learn more about the emission characteristics of odorants released from sewer manholes and stormwater catch basins (SCBs) in an urban environment, we measured the emission concentrations of major odorants including 22 target compounds designated as offensive odorants by the Korean Ministry of Environment (KMOE). All of our measurements were made from urban sewer manholes and SCBs in a highly commercialized location in Seoul, Korea. The results of our study were analyzed to identify the major odorants from such sources and to assess their contribution to odor intensity. The malodor strengths at both types of underground sources were considerably higher in the afternoon than in the morning. The assessment of odor intensity (OI) and odor activity value (OAV) confirmed the dominance of key odorants like H2S, CH3SH, and ammonia along with various volatile fatty acids (VFAs) and phenol. The concentration of these major odorants (H2S, CH3SH, and NH3) exceeded the maximum permissible limit given as the odor prevention law in Korea. As such, significantly high levels of odorants released from these underground sources were greatly distinguished from those seen at above ground locations. PMID:26775004

  14. A framework for identifying characteristic odor compounds in municipal wastewater effluent.

    PubMed

    Agus, Eva; Zhang, Lifeng; Sedlak, David L

    2012-11-15

    Municipal wastewater often contains trace amounts of organic compounds that can compromise aesthetics of drinking water and undermine public confidence if a small amount of effluent enters the raw water source of a potable water supply. To efficiently identify compounds responsible for odors in wastewater effluent, an analytical framework consisting of gas chromatography with mass spectrometry (GC-MS) and gas chromatography with olfactometry detection (GC-Olf) coupled with flavor profile analysis (FPA) was used to identify and monitor compounds that could affect the aesthetics of drinking water. After prioritizing odor peaks detected in wastewater effluent by GC-Olf, the odorous components were tentatively identified using retention indices, mass spectra and odor descriptors. Wastewater effluent samples were typically dominated by earthy-musty odors with additional odors in the amine, sulfidic and fragrant categories. 2,4,6-trichloroanisole (246TCA), geosmin and 2-methylisoborneol (2MIB) were the main sources of the earthy/musty odors in wastewater effluent. The other odors were attributable to a suite of compounds, which were detected in some but not all of the wastewater effluents at levels well in excess of their odor thresholds. In most cases, the identities of odorants were confirmed using authentic standards. The fate of these odorous compounds, including 2-pyrrolidone, methylnaphthalenes, vanillin and 5-hydroxyvanillin (5-OH-vanillin), should be considered in future studies of water systems that receive effluent from upstream sources. PMID:22981490

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

    NASA Astrophysics Data System (ADS)

    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 < 0.05). By contrast, the 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.

  16. Green Power

    ERIC Educational Resources Information Center

    Schaffhauser, Dian

    2009-01-01

    In the world of higher education, even the most ambitious sustainability plans often begin with tiny steps taken by individual departments. Michael Crowley, a program manager for Environmental Health & Engineering (EH&E) and former assistant director of the Harvard (Massachusetts) Green Campus Initiative, explains that going for small wins through…

  17. Going Green.

    ERIC Educational Resources Information Center

    Kennedy, Mike

    2001-01-01

    Discusses the benefits that schools and universities can gain by adopting environmentally sensitive practices in their design and operations. Includes resources for locating additional information about green schools and a list of 11 features that represent a comprehensive, sustainable school. (GR)

  18. Green pioneers.

    PubMed

    Trueland, Jennifer

    The government has set tough targets for the NHS in England to reduce its carbon footprint. In this article, nurses and managers at Nottinghamshire Healthcare NHS Trust explain how a programme of 'greening' initiatives - including a trial of electric cars for community staff - have slashed the trust's CO2 output. PMID:23763098

  19. Going Green

    ERIC Educational Resources Information Center

    Witkowsky, Kathy

    2009-01-01

    Going green saves money and can even make money. Sustainable practices promote better health, less absenteeism, and more productivity. They also attract students, who are paying increasing attention to schools' environmental policies. Beyond being the smart thing to do, administrators at the University of Washington say repeatedly, it's the right…

  20. Buying Green

    ERIC Educational Resources Information Center

    Layng, T. V. Joe

    2010-01-01

    In "Buying Green," Joe Layng recognizes that, like all choices we make, our decisions as consumers are more likely to be influenced by their short-term consequences for us as individuals (price, quality) than they are by their long-term consequences for society (environmental impact). He believes that the equation can be tilted in favor of greener…