scholarly journals Olfactory object recognition based on fine-scale stimulus timing in Drosophila

2018 ◽  
Author(s):  
Aarti Sehdev ◽  
Yunusa G. Mohammed ◽  
Tilman Triphan ◽  
Paul Szyszka
Keyword(s):  
Food Sources ◽  
Odor Source ◽  
Fine Scale ◽  
Sound Segregation ◽  
Temporal Cues ◽  
Stimulus Timing ◽  
Onset Asynchrony ◽  
Different Sources ◽  
Source Segregation ◽  
Do So

SUMMARYOdorants of behaviorally relevant objects (e.g., food sources) intermingle with those from other sources. Therefore, to sniff out whether an odor source is good or bad – without actually visiting it – animals first need to segregate the odorants from different sources. To do so, animals could use temporal cues, since odorants from one source exhibit correlated fluctuations, while odorants from different sources are less correlated. However, it remains unclear whether animals can rely solely on temporal cues for odor source segregation. Here we show that 1) flies can use a few milliseconds differences in odorant arrival to segregate a target odorant from a binary mixture, 2) segregation does not improve when the target odorant arrives first, and 3) segregation works for odorants with innate, as well as learned valences. These properties of odor segregation parallel those of concurrent sound segregation and figure-ground segregation by onset asynchrony in humans.

scholarly journals Unequal chances: ex ante fairness and individual control

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Leticia Micheli ◽  
Nickolas Gagnon
Keyword(s):  
Perceived Control ◽  
Online Survey ◽  
Family Income ◽  
Financial Outcomes ◽  
Individual Control ◽  
Ex Ante ◽  
And Gender ◽  
Different Sources ◽  
Do So

AbstractUnequal financial outcomes often originate from unequal chances. Yet, compared to outcomes, little is known about how individuals perceive unequal distributions of chances. We investigate empirically the role of different sources of unequal chances in shaping inequality perceptions. Importantly, we do so from an ex ante perspective—i.e., before the chances are realized—which has rarely been explored. In an online survey, we asked uninvolved respondents to evaluate ex ante the fairness of unequal allocations of chances. We varied the source of inequality of chances, using a comprehensive range of factors which resemble several real world situations. Respondents also evaluated how much control individuals hold over the distribution of chances. Results show that different sources generate different ex ante perception of fairness. That is, unequal chances based on socioeconomic and biological factors, such as gender, family income and ethnicity, are evaluated to be unfair relative to the same chances based on effort, knowledge, and benevolence. Results also show that, for most individuals, there is a positive correlation between perceived control of a factor and fairness of unequal chances based on that factor. Luck appears to be an exception to this correlation, ranking as high in fairness as effort, knowledge, and benevolence, but similarly low in individual control as ethnicity, family income, and gender.

scholarly journals Isolation of Enterococcus Species from Food Sources and Its Antibacterial Activity against Staphylococcus Aureus

2020 ◽  
pp. 3164-3171
Author(s):  
Andalus S. Atiyah ◽  
Marwa H. Alkhafaji
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Dairy Products ◽  
Food Samples ◽  
Food Sources ◽  
Enterococcus Spp ◽  
Microbial Defense ◽  
Prevalent Species ◽  
Different Sources ◽  
By Products

The microbial production of substances that have the ability to inhibit the growth of other microorganisms is possibly the most common defense strategy developed in nature. Microorganisms produce a variable collection of microbial defense systems, which include antibiotics, metabolic by-products, lytic agents, bacteriocins and others. The aim of the present study was to isolate and identify Enterococcus spp. and  its most prevalent species from food samples and determine its antibacterial activity against Staphylococcus aureus isolates. A total of 50 food samples from different sources (dairy products (20 samples) and vegetables and fish (15 samples each)) were collected from different local markets in Baghdad and cultured. Enterococcus spp were isolated from only 32 food samples. E. faecium was the most predominant species which was recovered from 20 samples (62.5 %), 10 dairies, 7 vegetables, and 2 fish. E. faecalis was found in 8 samples (25 %), 5 vegetables and 3 fish.  E. avium was recovered 6.25% as well as E. gallinarium (2 samples for each) Enterococcus avium were all isolated from dairy products but Enterococcus gallinarium one sample isolated from dairies and the other from fish. This study indicates the presence of Enterococcus spp. in the food samples and the ability of these bacteria to produce antibacterial substances which are active against closely related clinical isolates.

scholarly journals Female bed bugs (Cimex lectularius L) anticipate the immunological consequences of traumatic insemination via feeding cues

2019 ◽  
Vol 116 (29) ◽  
pp. 14682-14687 ◽  
Author(s):  
Michael T. Siva-Jothy ◽  
Weihao Zhong ◽  
Richard Naylor ◽  
Louise Heaton ◽  
William Hentley ◽  
...  
Keyword(s):  
Temporal Correlation ◽  
Copulatory Organ ◽  
Lifetime Reproductive Success ◽  
Bed Bugs ◽  
Temporal Cues ◽  
Infection Cycles ◽  
Fitness Benefits ◽  
Access To Food ◽  
Induced Immunity ◽  
Do So

Not all encounters with pathogens are stochastic and insects can adjust their immune management in relation to cues associated with the likelihood of infection within a life cycle as well as across generations. In this study we show that female insects (bed bugs) up-regulate immune function in their copulatory organ in anticipation of mating by using feeding cues. Male bed bugs only mate with recently fed females and do so by traumatic insemination (TI). Consequently, there is a tight temporal correlation between female feeding and the likelihood of her being infected via TI. Females that received predictable access to food (and therefore predictable insemination and infection cycles) up-regulated induced immunity (generic antibacterial activity) in anticipation of feeding and mating. Females that received unpredictable (but the same mean periodicity) access to food did not. Females that anticipated mating-associated immune insult received measurable fitness benefits (survival and lifetime reproductive success) despite laying eggs at the same rate as females that were not able to predict these cycles. Given that mating is a time of increased likelihood of infection in many organisms, and is often associated with temporal cues such as courtship and/or feeding, we propose that anticipation of mating-associated infection in females may be more widespread than is currently evidenced.

scholarly journals Olfactory Object Recognition Based on Fine-Scale Stimulus Timing in Drosophila

iScience ◽  
2019 ◽  
Vol 13 ◽  
pp. 113-124 ◽  
Author(s):  
Aarti Sehdev ◽  
Yunusa G. Mohammed ◽  
Tilman Triphan ◽  
Paul Szyszka
Keyword(s):  
Object Recognition ◽  
Fine Scale ◽  
Stimulus Timing

Multimodale Listen. Form und Funktion körperlicher Ressourcen in Aufzählungen in französischen, spanischen und italienischen Interaktionen

2019 ◽  
Vol 70 (1) ◽  
pp. 58-104
Author(s):  
Philipp Dankel ◽  
Ignacio Satti
Keyword(s):  
Conversation Analysis ◽  
Spoken Language ◽  
Interactional Linguistics ◽  
Form And Function ◽  
Cross Lingual ◽  
And Function ◽  
Different Sources ◽  
Do So

Abstract This article focuses on the practice of listing in Talk-in-Interaction. Lists are frequently used in spoken language as a discursive resource and can be considered as a universal, cross-lingual practice for structuring ideas. As such, they have been given attention in several fields of linguistics, mainly in intonation research, conversation analysis and interactional linguistics. However, the role of gestures and other physical forms of expression in listing has been mostly disregarded so far. For this reason, we attempt to cast light on the form and function of gestures and other bodily resources that are embedded in this practice. We argue that lists are multimodal and that bodily resources play a major role in establishing the format and in organizing the interaction. In order to do so, we use a broad collection of examples from different sources in French, Italian and Spanish.

scholarly journals Odor-background segregation of unknown odorants based on stimulus onset asynchrony in honey bees

2019 ◽  
Author(s):  
Aarti Sehdev ◽  
Paul Szyszka
Keyword(s):  
Stimulus Onset Asynchrony ◽  
Honey Bees ◽  
Stimulus Onset ◽  
Sensory Adaptation ◽  
Behavioral Experiments ◽  
Olfactory Information ◽  
Background Stimulus ◽  
Olfactory Organs ◽  
Onset Asynchrony ◽  
Different Sources

ABSTRACTAnimals use olfaction to search for distant objects. Unlike vision, where objects are spaced out, olfactory information mixes when it reaches olfactory organs. Therefore, efficient olfactory search requires segregating odors that are mixed with background odors. Animals can segregate known target odors by detecting short differences in the arrival of odorants from different sources (stimulus onset asynchrony). However, it is unclear whether animals can also use stimulus onset asynchrony to segregate previously unknown odorants that have no innate or learned relevance. Using behavioral experiments in honey bees, we here show that stimulus onset asynchrony also improves odor-background segregation of unknown odorants. The stimulus onset asynchrony necessary to behaviorally segregate unknown odorants is in the range of seconds, which is two orders of magnitude larger than the previously reported stimulus asynchrony sufficient for segregating known odorants. We propose that for unknown odorants, odor-background segregation requires sensory adaptation to the background stimulus.

Navigation Along Windborne Plumes of Pheromone and Resource-Linked Odors

2021 ◽  
Vol 66 (1) ◽  
pp. 317-336
Author(s):  
Ring T. Cardé
Keyword(s):  
Behavioral Response ◽  
Scale Structure ◽  
Turbulent Structure ◽  
Odor Source ◽  
Fine Scale ◽  
Odor Concentration ◽  
Flying Insects ◽  
Odor Plumes ◽  
Clean Air ◽  
Sequential Measurements

Many insects locate resources such as a mate, a host, or food by flying upwind along the odor plumes that these resources emit to their source. A windborne plume has a turbulent structure comprised of odor filaments interspersed with clean air. As it propagates downwind, the plume becomes more dispersed and dilute, but filaments with concentrations above the threshold required to elicit a behavioral response from receiving organisms can persist for long distances. Flying insects orient along plumes by steering upwind, triggered by the optomotor reaction. Sequential measurements of differences in odor concentration are unreliable indicators of distance to or direction of the odor source. Plume intermittency and the plume's fine-scale structure can play a role in setting an insect's upwind course. The prowess of insects in navigating to odor sources has spawned bioinspired virtual models and even odor-seeking robots, although some of these approaches use mechanisms that are unnecessarily complex and probably exceed an insect's processing capabilities.

Accounting for measurement errors when harmonising incongruent soil data − a case study

Soil Research ◽  
2018 ◽  
Vol 56 (8) ◽  
pp. 793
Author(s):  
D. M. Crawford ◽  
S. Norng ◽  
M. Kitching ◽  
N. Robinson
Keyword(s):  
Measurement Errors ◽  
Complete Information ◽  
Sufficient Information ◽  
Precision Data ◽  
External Sources ◽  
Alternative Approaches ◽  
Predicted Values ◽  
Different Sources ◽  
Do So

When collating soil data from different sources, the data should be congruent. Ordinary linear regression (OLR) has often been used to harmonise incongruent data. To do so, one of the sources is nominated as the reference and so is assumed to provide data that are determined without error despite evidence to the contrary. Alternative approaches that can handle errors in both variables, such as constructing a maximum likelihood functional relationship (MLFR), are seldom used. Two scenarios compared these two approaches using soil organic carbon data determined by the Walkley and Black method or the Dumas method. An inter-laboratory proficiency program provided data to represent an ideal scenario of complete information on precision, i.e. a mean and standard error of multiple determinations for each method as applied to each soil sample. In this scenario, it was found that the recovery of carbon was not consistent between laboratories or methods, nor was the precision of determinations consistent. Importantly, the precision data showed how neither method had an advantage and so could serve as a reference. Unfortunately, soil researchers are more likely to be trying to harmonise data from single determinations and have no data on the precision of either method. This second scenario was explored using legacy data and new data from re-analysis of 116 archived soil samples, with precision data from different external sources. Here the OLR regression coefficients were found to be much less accurate than those from using the MLFR harmonisation model. We concluded from these scenarios, that MLFR should be used to harmonise incongruent data when data on measurement errors are available. MLFR gave different predicted values to OLR while accounting for measurement errors in both variables. Where sufficient information on precision is lacking, OLR yields similar results and so may be an easier but less rigorous option. However, more research is needed to establish when OLR can be used versus when MLFR should be used.

scholarly journals Effect of Dual-Carrier Processing on the Intelligibility of Concurrent Vocoded Sentences

2018 ◽  
Vol 61 (11) ◽  
pp. 2804-2813
Author(s):  
Frédéric Apoux ◽  
Brittney L. Carter ◽  
Eric W. Healy
Keyword(s):  
Sound Source ◽  
Speech Intelligibility ◽  
Target Sentence ◽  
Sound Sources ◽  
Single Carrier ◽  
Sound Source Segregation ◽  
Onset Asynchrony ◽  
Source Segregation ◽  
Vocoded Speech

Purpose The goal of this study was to examine the role of carrier cues in sound source segregation and the possibility to enhance the intelligibility of 2 sentences presented simultaneously. Dual-carrier (DC) processing (Apoux, Youngdahl, Yoho, & Healy, 2015) was used to introduce synthetic carrier cues in vocoded speech. Method Listeners with normal hearing heard sentences processed either with a DC or with a traditional single-carrier (SC) vocoder. One group was asked to repeat both sentences in a sentence pair (Experiment 1). The other group was asked to repeat only 1 sentence of the pair and was provided additional segregation cues involving onset asynchrony (Experiment 2). Results Both experiments showed that not only is the “target” sentence more intelligible in DC compared with SC, but the “background” sentence intelligibility is equally enhanced. The participants did not benefit from the additional segregation cues. Conclusions The data showed a clear benefit of using a distinct carrier to convey each sentence (i.e., DC processing). Accordingly, the poor speech intelligibility in noise typically observed with SC-vocoded speech may be partly attributed to the envelope of independent sound sources sharing the same carrier. Moreover, this work suggests that noise reduction may not be the only viable option to improve speech intelligibility in noise for users of cochlear implants. Alternative approaches aimed at enhancing sound source segregation such as DC processing may help to improve speech intelligibility while preserving and enhancing the background.

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