Search Results (84)

The migratory locust, Locusta migratoria, possesses a highly specialized olfactory system that exhibits remarkable density-dependent plasticity, which plays a crucial role in the formation of large aggregations and the resulting severe crop damage. However, the mechanisms by which population density influences phase-related plasticity in olfactory perception remain largely unexplored. Here, we conducted a comprehensive, multi-level comparison of the peripheral olfactory system between solitary and gregarious locusts. We found that solitary male locusts display the highest total number of antennal sensilla, with basiconica sensilla being the most abundant and particularly prominent in this group. At the physiological level, solitary males also displayed the greatest overall sensitivity in their electroantennogram (EAG) responses to volatile compounds highly specific to both phase and sex. At the molecular level, solitary males exhibited a significant upregulation of Or genes across all sex-phase combinations. These findings illuminate the intricate adaptation strategies of the insect peripheral olfactory system in response to environmental changes. Full article

This study reconstructs the geography of meaning of the German perception verb schmecken on the basis of 30 major dialect dictionaries, treating them as a distributed semantic corpus and coding attestations as binary variables reflecting the presence or absence of semantic options. Combining a construal-based framework with spatial modeling, the analysis shows that the polysemy of schmecken is structured by three mutually reinforcing forces: embodied sensory organization, construal-based perspectivization, and regionally patterned areal dynamics. The gustatory–olfactory axis forms the semantic core of the verb, from which tactile, visual, affective, and epistemic extensions emerge. These extensions align with systematic pathways constrained by agentive, experiential, emissive, and evaluative construals, demonstrating that semantic extension is channeled through specific construal modes—notably emissive and agentive—rather than determined by sensory modality alone. A detailed areal analysis reveals a pronounced north–south divide. While Low German dialects conform to the cross-linguistically more common tendency to avoid colexifying taste and smekk—itself the outcome of historical change rather than uninterrupted differentiation—Upper German varieties preserve a typologically rare gustatory–olfactory cluster and exhibit the richest range of cross-modal and abstract extensions. The resulting semantic graph formalizes how regional varieties activate different subsets of a lexeme’s semantic potential and demonstrates that semantic networks themselves display spatial organization. The study thus provides an empirically grounded reconstruction of a German geography of meaning and illustrates how dialect data illuminate the interplay between embodied cognition, construal-based lexical architecture, and areal dynamics. Full article

A growing body of evidence indicates that the gut microbiota has a role in the mating preference process in mammals. This likely occurs through the modulation of various mating signals induced by symbiotic bacteria, thereby leading to variations in mating behavior. Given that giant pandas are solitary wild animals that rely on chemical signals for mate selection, it is relevant to explore whether the mating behavior of giant pandas is also affected by the gut microbiota. We hypothesize that antibiotic treatment-induced residual antibiotic resistance genes in captive giant pandas may disrupt intestinal microbiota homeostasis, diminish the abundance of beneficial microorganisms involved in short-chain fatty acid synthesis, and consequently impair nervous system function via the gut–brain axis. The ensuing physiological stress is likely to suppress innate mating behavior and compromise pheromone synthesis, thereby reducing an individual’s attractiveness to potential mates. To answer this question, we utilize fecal metagenomics technology to analyze the differences in gut microbes and antibiotic resistance genes (ARGs) between captive male adult giant pandas displaying natural versus non-natural mating behavior. The research findings suggest that, when compared with captive adult male giant pandas demonstrating natural mating behavior, those with non-natural mating behavior exhibit a significantly reduction in the abundance of beneficial gut microorganisms (s_Clostridium sp. and f_Ruminococcaceae) (p < 0.05). Concurrently, there is a significantly increase in the observed resistance genes tetO and mgtA, which are mainly associated with macrolide and tetracycline resistance (p < 0.05). Furthermore, Kegg functional analysis reveals a significant up-regulation of metabolic pathways related to sensory systems, such as taste and olfactory transduction, in the intestines of captive adult male giant pandas showing natural mating behavior. These results imply that changes in the abundance of gut microbiota and ARGs are correlated with the manifestation of natural mating behavior in captive adult male giant pandas. Consequently, to improve the success rate of natural reproduction within the male giant panda populations in captive environments, it is advisable to administer antibiotics judiciously and closely monitor the composition of beneficial bacteria in their gut microbiota. The findings of this study provide novel perspectives on the mechanisms by which captive conditions affect the decline in natural mating behavior observed in adult male giant pandas. Full article

Anastatus orientalis, a prominent egg parasitoid of Lycorma delicatula, demonstrates considerable potential for biological control. A. orientalis is dependent on host volatiles to identify and locate appropriate hosts for reproduction, with its olfactory system playing a vital role in volatile detection. There is little known about the chemosensory genes in A. orientalis. Therefore, here, we conducted a transcriptome analysis of the males and females from A. orientalis. Overall, 24 odorant binding proteins (OBPs), 4 chemosensory proteins (CSPs), 26 odorant receptors (ORs), 3 gustatory receptors (GRs), 3 ionotropic receptors (IRs), and 2 sensory neuron membrane proteins (SNMPs) were identified by transcriptome analysis. The values for fragments per kilobase per million (FPKM) indicated that the chemosensory protein gene families in A. orientalis exhibit different expression levels in male and female adults, with some genes showing significant differences and displaying sex-biased expression. Furthermore, RACE technology, phylogenetic analysis, and expression analysis were used to investigate the role that AoOBP8 plays in olfaction in A. orientalis. AoOBP8 was highly expressed in females and the heads of adults, indicating that the gene has a crucial role to play in the search for hosts and in oviposition in female adults, while the head is crucial in recognizing chemical information. These results contribute to a deeper understanding of the functions of chemosensory protein gene families in A. orientalis and offer a reference for developing biocontrol methods for forestry pests. Full article

This study examines the impact of olfactory stimuli on user experience (UX) metrics in 360-degree videos under varying levels of audio–visual (AV) skew. Subjective responses and questionnaire results revealed that scents helped stabilize enjoyment and artifact tolerance scores, particularly under severe AV skews, compared to non-olfactory conditions. However, the stationary nature of the scent delivery device decreased the intensity of olfactory stimuli, limiting their potential impact. Objective analyses highlighted a masking effect in 360-degree videos, where participant visual exploration reduced sensitivity to AV skews. Despite these challenges, olfactory stimuli demonstrated resilience to AV skews, suggesting their potential to buffer negative effects and enhance immersive experiences. However, they did not significantly improve overall video quality ratings. The study underscores the need for advances in olfactory display technology, such as head-mounted scent emitters and dynamic sensory integration, to enhance multimedia experiences. Full article

Aedes aegypti, also known as the yellow fever mosquito, presents a major public health challenge, highlighting the need for effective biorational agents for mosquito control. Here, we investigated the synergistic effects of essential oil mixtures derived from Hypenia irregularis that is a mint-family shrub native to Brazil’s Cerrado biome, known as “alecrim do Cerrado”, in combination with essential oils from noni (Morinda citrifolia), Brazilian mint (“salva-do-Marajó”, Hyptis crenata), and lemongrass (Cymbopogon citratus) against Ae. aegypti. We conducted phytochemical analyses and assessed larvicidal, repellent, and oviposition deterrent activities. Using in silico methods, we predicted molecular interactions between key essential oil components and physiological targets involved in repellent action (odorant-binding protein AeagOBP1 and olfactory receptor Or31) and larvicidal activity (GABA and octopamine receptors, TRP channels, and acetylcholinesterase [AChE]). Major compounds identified included octanoic acid (23%; Hipe. irregularis × M. citrifolia), 2,5-dimethoxy-p-cymene (21.9%; Hipe. irregularis × Hypt. crenata), and citral (23.0%; Hipe. irregularis × C. citratus). Although individual oils showed strong larvicidal activity (Hipe. irregularis LC₅₀ = 2.35 µL/mL; Hypt. crenata = 2.37 µL/mL; M. citrifolia and C. citratus = 2.71 µL/mL), their mixtures did not display synergistic effects. Similarly, repellency and oviposition deterrence were comparable to DEET for individual oils but were not enhanced in mixtures. Notably, the Hipe. irregularis × C. citratus essential oil blend reduced oviposition deterrence. Molecular docking confirmed strong binding of major oil components to AeagOBP1 and Or31, supporting their role in repellency. For larvicidal effects, AChE showed the highest predicted binding affinity. Overall, our findings suggest that H. irregularis, Hypt. crenata, C. citratus, and M. citrifolia (alone or in 1:1 mixture) are promising, sustainable agents for A. aegypti control. Full article

Euplatypus parallelus is a polyphagous pest capable of harming multiple plant species. Adult beetles invade tree trunks by boring holes, which negatively impacts the trees’ growth and may result in tree death. E. parallelus depends on plant volatiles to identify and locate appropriate hosts for feeding or reproduction, with its olfactory system playing a vital role in volatile detection. In this work, we applied transcriptomics, phylogenetic analysis, and expression analysis to investigate four chemosensory membrane protein gene families that play a role in olfaction in E. parallelus. Based on the annotation analysis, 41 odorant receptors (ORs), 12 gustatory receptors (GRs), 14 ionotropic receptors (IRs), and 4 sensory neuron membrane proteins (SNMPs) were identified in the head. We used differential gene expression (DGE) and fragments per kilobase per million (FPKM) values to compare the transcription levels of chemosensory membrane protein gene families between males and females. The data indicate that the chemosensory membrane protein gene families in E. parallelus exhibit different expression levels in male and female heads, with some genes showing significant differences and displaying sex-biased expression. These results offer a basis for future exploration of the functions of chemosensory membrane protein gene families in E. parallelus and offer a theoretical framework for designing innovative eco-friendly control technologies. Full article

Background/Objectives: Autism is a complex neurodevelopmental disorder characterized by restricted behaviors and impaired social and communication skills. The exact cause of autism remains unknown. One promising animal model for studying autism is the valproic acid rat model. Due to a 1 to 4 bias for males in autism occurrence, most animal model studies investigate only males and neglect females. However, female autism often appears different from that observed in males. Females are said to be less regularly diagnosed because they can “mask” their symptoms. Female autism is as necessary to investigate as male autism. Methods: Fertile adult female Sprague-Dawley rats were impregnated and injected with valproic acid on gestational day 13. Male and female offspring were subjected to behavioral tests to investigate autistic symptoms. Tests included novel object recognition, balance-beam, Y-maze, hole-board, three-chamber, marble burying, olfactory, light/dark and hot plate tests. Results: The tests revealed that VPA-exposed rats had increased anxiety-like behaviors, hyperactivity, and impaired non-verbal communication. However, they did not display repetitive behaviors or cognitive impairments. Notably, male and female rats showed different autism-like traits, with both showing hyperactivity, and males (but not females) additionally showing impaired sociability and increased anxiety. Conclusions: The findings suggest that prenatal exposure to VPA induces autism-like behaviors in both male and female Sprague-Dawley rat offspring. However, males appear more impacted by VPA exposure as evinced by their display of more autism-like symptoms relative to females. This study provides support for including both sexes in all studies modelling autism, as outcomes are seemingly impacted by the sex being observed. Full article

Bats are the only mammals with the ability to fly and are the second largest order after rodents, with 20 families and 1213 species (over 3000 subspecies) and are widely distributed in regions around the world except for Antarctica. What makes bats unique are their biological traits: a tolerance to zoonotic infections without getting clinical symptoms, long lifespans, a low incidence of tumors, and a high metabolism. As a result, they are receiving increasing attention in the field of life sciences, particularly in medical research. The rapid advancements in sequencing technology have made it feasible to comprehensively analyze the diverse biological characteristics of bats. This review comprehensively discusses the following: (1) The assembly and annotation overview of 77 assemblies from 54 species across 11 families and the transcriptome sequencing overview of 42 species from 7 families, focused on a comparative analysis of genomic architecture, sensory adaptations (auditory, visual, and olfactory), and immune functions. Key findings encompass marked interspecies divergence in genome size, lineage-specific expansions/contractions of immune-related gene families (APOBEC, IFN, and PYHIN), and sensory gene adaptations linked to ecological niches. Notably, echolocating bats exhibited convergent evolution in auditory genes (SLC26A5 and FOXP2), while fruit-eating bats displayed a degeneration of vision-associated genes (RHO), reflecting trade-offs between sensory specialization and ecological demands. (2) The annotation of the V (variable), D (diversity), J (joining), and C (constant) gene families in the TR and IG loci of 12 species from five families, with a focus on a comparative analysis of the differences in TR and IG genes and CDR3 repertoires between different bats and between bats and other mammals, provides us with a deeper understanding of the development and function of the immune system in organisms. Integrated genomic, transcriptomic, and immune repertoire analyses reveal that bats employ distinct antiviral strategies, primarily mediated by enhanced immune tolerance and suppressed inflammatory responses. This review provides foundational information, collaboration directions, and new perspectives for various laboratories conducting basic and applied research on the vast array of bat biology. Full article

Olfaction plays a crucial role in crustaceans for essential activities such as foraging and predator evasion. Among the components involved in olfactory perception, Ionotropic Receptors (IRs) are particularly important. Oratosquilla oratoria, a perennial crustacean of substantial economic and ecological value, serves as an ideal model for studying olfactory mechanisms. Identifying the IR chemosensory genes in O. oratoria enhances our understanding of its olfactory recognition system. Based on the whole-genome data of O. oratoria, we identified and analyzed 50 members of the IR gene family (OratIRs) through bioinformatics approaches. These genes were classified into subfamilies of co-receptor IRs and tuning IRs. The physicochemical properties of the encoded proteins exhibit marked variability, indicating distinct roles. The motif types and conserved domains among these subfamilies display certain similarities, but their gene structures differ markedly. Furthermore, we found that OratIR25a, OratIR07629, and OratIR14286 are key nodes in protein–protein interaction networks, coordinating organisms’ responses to signals like temperature and acids. We utilized fluorescence in situ hybridization (FISH) to find that OratIR75-1 and OratIR8a demonstrated robust expression signals in the antennae of the O. oratoria. These findings lay a foundation for further investigations and elucidate the functional roles of olfactory receptor genes in crustaceans. Full article

Indoor air quality (IAQ) plays a vital role in supporting both the physical and mental well-being of individuals in enclosed spaces, and the role of mechanical ventilation systems has gained increasing attention due to building design’s focus on energy efficiency and thus airtight constructions. This study investigated the pre–post effects of installing a heat recovery mechanical ventilation system (MVHR) on indoor air quality in a high school classroom in Ferrara, Italy. The analysis focused on experimental measurements of temperature (T), relative humidity (RH), and carbon dioxide (CO₂) both inside and outside the same classroom, which had constant occupancy (17 students) for an entire school year, allowing a comparison between natural and mechanical ventilation. With a comprehensive approach, particulate matter (PM_2.5), volatile organic compounds (VOCs), and radon levels (Rn) were monitored as well, after the installation of the MVHR. By comparing natural and mechanical ventilation, the study highlights the strengths and limitations of the ventilation system implemented, together with an evaluation of the system’s energy consumption, including a 2 kW post-heating battery. In terms of results, the MVHR demonstrated clear benefits in managing CO₂ levels and improving sensory, olfactory, and psychophysical well-being, as well as the attention levels of students. In detail, under natural ventilation, peak concentrations exceeded 4500 ppm, while mechanical ventilation kept them below 1500 ppm. The average CO₂ concentration during occupancy dropped from 2500 ppm to around 1000 ppm, achieving a 62% reduction. However, beneficial effects were not observed for other parameters, such as PM_2.5, VOCs, or radon. The latter displayed annual average values around 21 Bq/m³ and peaks reaching 56 Bq/m³. Full article

The ORA (olfactory receptor class A) gene family in teleosts is related to the V1R (vomeronasal 1 receptors) family in mammals and plays a key role in odor detection. Although ORA genes have been identified in several teleosts, their characteristics in mandarin fish (Siniperca chuatsi) have not been explored. In this study, we conducted a comprehensive genomic analysis of the mandarin fish and discovered a complete ORA gene family consisting of five members located on chromosome 2 (ORA1, ORA2, ORA3, ORA4) and chromosome 16 (ORA6). Phylogenetic, synteny, and gene structure analyses revealed typical exon–intron conservation with strong evidence of purifying selection. Tissue expression analysis showed distinct expression profiles for each ORA gene, with some showing sexual dimorphism in specific tissues. The expression of ORA1 and ORA2 in the olfactory epithelium exhibits sexual dimorphism, while ORA3 shows sexual dimorphism in the brain. In situ hybridization confirmed that ORA1, ORA2, ORA3, and ORA6 are expressed in the microvillar sensory neurons of the olfactory epithelium, while ORA4 is expressed in crypt cells. Additionally, molecular docking simulations indicated that the five ORA proteins have a high binding affinity with seven bile acids (LAC, GLAC, CA, TLCA, 3-KLCA, 7-KLCA, and 12-KLCA), with ORAs showing stronger binding affinity with LCA and CA. This study comprehensively characterizes the ORA gene family in mandarin fish, examining its phylogeny, synteny, gene structure, and selection pressure. Furthermore, we found that each ORA displays a distinct expression pattern across multiple tissues, with notable sexual dimorphism, and shows potential binding interactions with specific bile acids and pheromones. Our findings provide valuable insights that enhance the overall understanding of fish ORAs and their potential functions. Full article

Brain size asymmetry differs considerably across species, including humans, vertebrates, and invertebrates. The subtle structural, functional, or size differences between the two brain sides are associated with processing specific cognitive tasks. To evaluate the differences between the sizes of the left and right sides of the whole brain and brain regions and the effect of predation risk (i.e., snake density) on brain size asymmetry among Chinese anurans, we compared the differences between the left and right hemisphere sizes of the whole brain and brain regions among anuran species and analyzed the correlations between the predation risk and size asymmetry index of the brain and brain regions. We found that when one side of the brain was consistently larger than the other, there was a significant difference between the sizes of the left and right sides of the brain and brain regions, displaying directional asymmetry of the whole brain and brain regions. We also found that total brain size was positively correlated with the size asymmetry index of the olfactory bulb and optic tecta when the left hemispheres of the whole brain and brain regions were larger than the right ones. Meanwhile, the index of telencephalon size asymmetry was positively correlated with predation risk when the right hemispheres of the brain and brain regions were larger than the left ones. However, there were non-significant differences between the sizes of the left and right sides of the brain and brain regions across 99 species of anurans. Our findings suggest that an increased predation risk linked to sociality is likely to drive an increase in right telencephalon size. Full article

To better cope with stress in emergencies, emergency personnel undergo virtual reality (VR) stress training. Such training typically includes visual, auditory and sometimes tactile impressions, whereas olfactory stimuli are mostly neglected. This concept paper therefore examines whether odors might be beneficial for further enhancing the experience of presence and immersion into a simulated environment. The aim is to demonstrate the benefits of VR civilian stress training for emergency personnel and to investigate the role of odors as stressors by manipulating the degree of perceived psychophysiological stress via olfactory impressions. Moreover, the current paper presents the development and validation of a convenient and portable fragrance dosing system that allows personalized odor presentation in VR. The presented system can transport reproducible small quantities of an air-fragrance mixture close to the human nose using piezoelectric stainless steel micropumps. The results of the fluidic system validation indicate that the micropump is suitable for releasing odors close to the nose with constant amounts of odor presentation. Furthermore, the theoretical background and the planned experimental design of VR stress training, including odor presentation via olfactory VR technology, are elucidated. Full article

Pesticides can induce target plants to release odors that are attractive or repellent to their herbivore insects. But, to date, the activity of volatile organic compounds (VOCs), singly or as mixtures, which play a crucial role in the olfactory behavior of herbivore insects, remains unclear. The objective of our research was to investigate the impact of thiamethoxam (TMX), a pesticide, on the emission of odors by wheat plants, and how these odors influence the behavior of grain aphids (Sitobion miscanthi). S. miscanthi showed a greater repellent response to the volatiles emitted by Thx-induced plants compared to those emitted by uncoated plants. Using gas chromatography–mass spectrometry (GCMS), we discovered that TMX greatly induced the release of VOCs in wheat plants. For instance, the levels of Bornyl acetate, 2-Oxepanone, Methyl acrylate, Cyclohexene, α-Pinene, and 1-Nonanol in coated wheat plants were significantly higher as compared to uncoated wheat plants. Moreover, varying concentrations also had an impact on the olfactory behavior of S. miscanthi. For instance, Cyclohexene exhibited clear attractiveness to aphids at concentrations of 100 μL/mL, whereas it displayed evident repellent properties at concentrations of 1 μL/mL and 10 μL/mL. These new findings demonstrate how TMX-induced VOCs affect the behavior of S. miscanthi and could help in developing innovative approaches to manage aphids by manipulating the emission of plant volatiles. Furthermore, these findings can also be utilized to evaluate substances that either attract or repel aphids, with the aim of implementing early monitoring and environmentally friendly methods to manage aphids, while simultaneously impeding the spread of viruses. Full article