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1.
Exp Eye Res ; 248: 110066, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39233305

RESUMEN

The eye lens contains convexly curved fiber cells that align in concentric layers around the lens anterior-posterior pole axis. For lens fiber differentiation at the equator, cells elongate with their apical and basal tips migrating towards the anterior and posterior poles, respectively. At each pole, the fiber tips meet opposing tips of other fiber cells, to form a suture. Although umbilical or point sutures are observed in fish and birds, line, Y- or star-shaped sutures are detected in other vertebrate lenses. Sutures that do not converge at the point are thought to result from intricate movements of the fiber tips, rather than a straightforward migration along a meridional path. The triggers that give rise to these variations are currently not understood. Our findings revealed that in the mouse embryo, the early-stage lens contains only concave curved fibers, and later, a zone of concave-to-convex curve conversion develops. At this point, a nascent suture in a linear shape appears at the posterior pole and subsequently progresses into a V-shape. This V-shape appears to further develop into a Y-shape as a branch extends from the apex of the V-shape. In lens of zebrafish and Xenopus larvae that form point sutures, this curve-conversion zone is not observed. In lens of adult birds (e.g. zebra finch) that form a point suture, these too also lack a curve-conversion zone. In our previous studies, we demonstrated that murine lens fibers undergoing curve conversion extend membrane protrusions, or lamellipodia, at their basal membranes. In line with this, we did not observe protrusions at the basal tips of fibers in the non-mammalian lenses of zebrafish, Xenopus, and zebra finch in which curve conversion does not occur. We propose that the concave-to-convex conversion in rodent lenses introduces defined paths for fiber cell tips, leading to a more elaborate and complex suture formation, compared to the simple point suture of lower vertebrates.

2.
Plants (Basel) ; 13(17)2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39273830

RESUMEN

Plant seedling morphogenesis is considerably related to photosynthesis, pigment synthesis, and circadian periodicity during seedling development. We identified and cloned a maize zebra or crossbanding leaves mutant wk3735, which produces pale white kernels and was identified and plays a role in the equilibrium of the Redox state the in/out of ETC by active oxygen scavenging. Interestingly, it produces the zebra leaves during the production of the first seven leaves, which is apparently different from the mutation of homologs AtPTOX in Arabidopsis. It is intriguing to investigate how and why yellow crossbands (zebra leaf phenotype) emerge on leaves. As expected, chlorophyll concentration and photosynthetic efficiency both significantly declined in the yellow sector of wk3735 leaves. Meanwhile, we observed the circadian expression pattern of ZmPTOX1, which was further validated by protein interaction assays of the circadian clock protein TIM1 and ZmPTOX1. The transcriptome data of yellow (muW) and green (muG) sectors of knock-out lines and normal leaves of overexpression lines (OE) at the 5th-leaf seedling stage were analyzed. Zebra leaf etiolated sections exhibit a marked defect in the expression of genes involved in the circadian rhythm and rhythmic stress (light and cold stress) responses than green sections. According to the analysis of co-DEGs of muW vs. OE and muG vs. OE, terms linked to cell repair function were upregulated while those linked to environmental adaptability and stress response were downregulated due to the mutation of ZmPTOX1. Further gene expression level analyses of reactive oxygen species (ROS) scavenging enzymes and detection of ROS deposition indicated that ZmPTOX1 played an essential role in plant stress resistance and ROS homeostasis. The pleiotropic roles of ZmPTOX1 in plant ROS homeostasis maintenance, stress response, and circadian rhythm character may collectively explain the phenotype of zebra leaves during wk3735 seedling development.

3.
Accid Anal Prev ; 208: 107783, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39288452

RESUMEN

Autonomous vehicles (AVs) offer a range of substantial safety and mobility benefits. However, successful deployment of AVs will involve interacting with other road users, such as pedestrians and other human-driven vehicles. While previous research has focused on factors that influence perceptions of AVs, less work has addressed how specific interactions with other road users influence acceptability from multiple perspectives. Accordingly, we conducted six studies examining how vehicles, either human-driven or autonomous, should behave at a zebra crossing in terms of stopping distance from the crossing, how long a vehicle should wait before setting off, and the influence of traffic context. Using computer-generated videos we found that: the optimal stopping distance was just before the stop line; participants were generally accepting of a vehicle that waited until a pedestrian had fully cleared the crossing before setting off, and sometime earlier; the presence of other vehicles, context and observer viewpoint can affect judgements of vehicle behaviour; autonomous vehicles were judged more harshly than human drivers with learner drivers judged less harshly in some circumstances, and that vehicle size appeared to have little influence over the acceptability of vehicle behaviours. The results are important for informing the design of autonomous vehicle manoeuvres from the viewpoints of vehicle occupants and other road users.

4.
Mol Ecol Resour ; : e14021, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39279489

RESUMEN

DNA methylation (DNAm) is a mechanism for rapid acclimation to environmental conditions. In natural systems, small effect sizes relative to noise necessitates large sampling efforts to detect differences. Large numbers of individually sequenced libraries are costly. Pooling DNA prior to library preparation may be an efficient way to reduce costs and increase sample size, yet there are to date no recommendations in ecological epigenetics research. We test whether pooled and individual libraries yield comparable DNAm signals in a natural system exposed to different pollution levels by generating whole-epigenome data from two invasive molluscs (Corbicula fluminea, Dreissena polymorpha) collected from polluted and unpolluted localities (Italy). DNA of the same individuals were used for pooled and individual epigenomic libraries and sequenced with equivalent resources per individual. We found that pooling effectively captures similar genome-wide and global methylation signals as individual libraries, highlighting that pooled libraries are representative of the global population signal. However, pooled libraries yielded orders of magnitude more data than individual libraries, which was a consequence of higher coverage. We would therefore recommend aiming for a high initial coverage of individual libraries (15×) in future studies. Consequently, we detected many more differentially methylated regions (DMRs) with the pooled libraries and a significantly lower statistical power for regions from individual libraries. Computationally pooled data from the individual libraries produced fewer DMRs and the overlap with wet-lab pooled DMRs was relatively low. We discuss possible causes for discrepancies, list benefits and drawbacks of pooling, and provide recommendations for future epigenomic studies.

5.
Cell Rep Methods ; 4(9): 100844, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39232558

RESUMEN

Understanding animal behavior is crucial in behavioral neuroscience, aiming to unravel the mechanisms driving these behaviors. A significant milestone in this field is the analysis of behavioral reactions during social interactions. Despite their importance in social learning, the behavioral aspects of these interaction are not well understood in detail due to the lack of appropriate tools. We introduce a high-precision, marker-based motion-capture system for analyzing behavior in songbirds, accurately tracking body location and head direction in multiple freely moving finches during social interaction. Focusing on zebra finches, our analysis revealed variations in eye use based on individuals presented. We also observed behavioral changes during virtual and live presentations and a conditioned-learning paradigm. Additionally, the system effectively analyzed social interactions among mice. This system provides an efficient tool for advanced behavioral analysis in small animals and offers an objective method to infer their focus of attention.


Asunto(s)
Atención , Conducta Animal , Pinzones , Interacción Social , Animales , Conducta Animal/fisiología , Atención/fisiología , Pinzones/fisiología , Ratones , Masculino , Pájaros Cantores/fisiología , Conducta Social
6.
R Soc Open Sci ; 11(6): 240007, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39100151

RESUMEN

Flying animals have had to evolve robust and effective guidance strategies for dealing with habitat clutter. Birds and insects use optic flow expansion cues to sense and avoid obstacles, but orchid bees have also been shown to use brightness cues during gap negotiation. Such brightness cues might therefore be of general importance in structuring visually guided flight behaviours. To test the hypothesis that brightness cues also affect gap negotiation behaviours in birds, we presented captive zebra finches Taeniopygia guttata with a symmetric or asymmetric background brightness distribution on the other side of a tunnel. The background brightness conditions influenced both the birds' decision to enter the tunnel aperture, and their flight direction upon exit. Zebra finches were more likely to initiate flight through the tunnel if they could see a bright background through it; they were also more likely to fly to the bright side upon exiting. We found no evidence of the centring response that would be expected if optic flow cues were balanced bilaterally during gap negotiation. Instead, the birds entered the tunnel by targeting a clearance of approximately one wing length from its near edge. Brightness cues therefore affect how zebra finches structure their flight when negotiating gaps in enclosed environments.

7.
J Exp Biol ; 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39206634

RESUMEN

It is widely accepted that birds can adaptively regulate body mass in different ecological contexts, but little is known about how birds monitor and interpret their body mass or the mechanisms that allow for rapid changes in mass. Using captive zebra finches (Taeniopygia guttata), we experimentally increased perceived mass via attachment of weighted backpacks and provided birds with either an ad libitum mixed-seed diet or supplementary high-fat diet to investigate (a) how birds assess their own body mass and (b) the physiological and/or behavioral mechanisms birds may employ to rapidly adjust body mass. In both experiments, and independent of diet treatment, birds with weighted backpacks rapidly lost mass within two days of backpack attachment while reducing overall activity and maintaining food intake. Additionally, our data suggest that birds interpret body mass via a physical mechanosensory pathway rather than a physiological pathway: rapid loss of mass between days 0 and 2 was not linked to changes in plasma metabolites (glycerol or triglyceride concentrations). We found no evidence that mass loss was a consequence of stress associated with attachment of weighted backpacks (based on plasma corticosterone measures). Our results suggest that the processes of energy balance and mass regulation involve a greater array of mechanisms than simply matching energy in through the amount of food consumed to energy out, dictated by activity: zebra finches were able to decrease body mass through other, unidentified, mechanisms even while maintaining dietary intake and reducing overall activity.

8.
Int Immunopharmacol ; 140: 112856, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39121609

RESUMEN

BACKGROUND: Wound healing pivots on a finely orchestrated inflammatory cascade, critical for tissue repair. Chronic wounds, compounded by persistent inflammation and susceptibility to infection, pose formidable clinical challenges. Nanofiber dressings offer promising avenues for wound care, yet their interaction with inflammation and infection remains elusive. We aim to delineate the inflammatory cascade preceding wound closure and assess Cu@Bbc nanofibers' therapeutic efficacy in mitigating inflammation and combating infection. Their unique attributes suggest promise in modulating inflammation, fostering tissue regeneration, and preventing microbial colonization. Investigating the intricate interplay between nanofiber scaffolds, inflammation, and infection may unveil mechanisms of enhanced wound healing. Our findings could stimulate the development of tailored dressings, urgently needed for effective wound management amidst immune dysregulation, infection, and inflammation. METHODS: In this investigation, we synthesized Cu@Bbc nanofibers, incorporating curcumin and berberine chloride, for wound healing applications. We evaluated their individual and combined antibacterial, anti-biofilm, and antioxidant activities, alongside binding affinity with pro-inflammatory cytokines through molecular docking. Morphological characterization was conducted via SEM, FTIR assessed functional groups, and wettability contact angle measured hydrophobic properties. The physical properties, including tensile strength, swelling behavior, and thermal stability, were evaluated using tensile testing, saline immersion method and thermogravimetric analysis. Biodegradability of the nanofibers was assessed through a soil burial test. Biocompatibility was determined via MTT assay, while wound healing efficacy was assessed with in vitro scratch assays. Controlled drug release and antibacterial activity against MRSA were examined, with in vivo assessment in a zebrafish model elucidating inflammatory responses and tissue remodeling. RESULTS: In this study, the synergistic action of curcumin and berberine chloride exhibited potent antibacterial efficacy against MRSA, with significant anti-mature biofilm disruption. Additionally, the combination demonstrated heightened antioxidant potential. Molecular docking studies revealed strong binding affinity with pro-inflammatory cytokines, suggesting a role in expediting the inflammatory response crucial for wound healing. Morphological analysis confirmed nanofiber quality, with drug presence verified via FTIR spectroscopy. Cu@Bbc demonstrated higher tensile strength, optimal swelling behavior, and robust thermal stability as evaluated through tensile testing and thermogravimetric analysis. Additionally, the Cu@Bbc nanofiber showed enhanced biodegradability, as confirmed by the soil burial test. Biocompatibility assessments showed favorable compatibility, while in vitro studies demonstrated potent antibacterial activity. In vivo zebrafish experiments revealed accelerated wound closure, re-epithelialization, and heightened immune response, indicative of enhanced wound healing. CONCLUSION: In summary, our investigation highlights the efficacy of Cu@Bbc nanofibers, laden with curcumin and berberine chloride, in displaying robust antibacterial and antioxidant attributes while also modulating immune responses and inflammatory cascades essential for wound healing. These results signify their potential as multifaceted wound dressings for clinical implementation.


Asunto(s)
Antibacterianos , Berberina , Curcumina , Staphylococcus aureus Resistente a Meticilina , Nanofibras , Infecciones Estafilocócicas , Cicatrización de Heridas , Pez Cebra , Animales , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Curcumina/farmacología , Curcumina/química , Curcumina/uso terapéutico , Berberina/farmacología , Berberina/química , Berberina/uso terapéutico , Cicatrización de Heridas/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/inmunología , Nanofibras/química , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antibacterianos/química , Sinergismo Farmacológico , Simulación del Acoplamiento Molecular , Citocinas/metabolismo , Biopelículas/efectos de los fármacos , Humanos , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico
9.
Environ Sci Technol ; 58(37): 16454-16464, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39214627

RESUMEN

Biogenic carbonates, including bivalve shells, record past environmental conditions, but their interpretation requires understanding environmental and biological factors that affect trace metal uptake. We examined stable barium (δ138Ba) and radiogenic strontium (87Sr/86Sr) isotope ratios in the aragonite shells of four native freshwater mussel species and two invasive species in five streams and assessed the effects of species identity, growth rate, and river water chemistry on shell isotopic composition. Shells were robust proxies for Sr, accurately reflecting 87Sr/86Sr ratios of river water, regardless of species or growth rate. In contrast, shell δ138Ba values, apart from invasive Corbicula fluminea, departed widely from those of river water and varied according to species and growth rate. Apparent fractionation between river water and the shell (Δ138Bashell-water) reached -0.86‰, the greatest offset observed for carbonate minerals. The shell deposited during slow growth periods was more enriched in lighter Ba isotopes than the rapidly deposited shell; thus, this phenomenon cannot be explained by aragonite precipitation kinetics. Instead, biological ion transport processes linked to growth rate may be largely responsible for Ba isotope variation. Our results provide information necessary to interpret water chemistry records preserved in shells and provide insights into biomineralization processes and bivalve biochemistry.


Asunto(s)
Exoesqueleto , Bario , Bivalvos , Agua Dulce , Isótopos de Estroncio , Animales , Exoesqueleto/química , Agua Dulce/química , Estroncio , Monitoreo del Ambiente , Isótopos , Corbicula/metabolismo
10.
Res Sq ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38978588

RESUMEN

Background: Vocal learning is a rare, convergent trait that is fundamental to both human speech and birdsong. The Forkhead Box P2 (FoxP2) transcription factor appears necessary for both types of learned signals, as human mutations in FoxP2 result in speech deficits, and disrupting its expression in zebra finches impairs male-specific song learning. In juvenile and adult male finches, striatal FoxP2 mRNA and protein decline acutely within song-dedicated neurons during singing, indicating that its transcriptional targets are also behaviorally regulated. The identities of these targets in songbirds, and whether they differ across sex, development and/or behavioral conditions, are largely unknown. Results: Here we used chromatin immunoprecipitation followed by sequencing (ChIP-Seq) to identify genomic sites bound by FoxP2 in male and female, juvenile and adult, and singing and non-singing birds. Our results suggest robust FoxP2 binding concentrated in putative promoter regions of genes. The number of genes likely to be bound by FoxP2 varied across conditions, suggesting specialized roles of the candidate targets related to sex, age, and behavioral state. We validated these binding targets both bioinformatically, with comparisons to previous studies and biochemically, with immunohistochemistry using an antibody for a putative target gene. Gene ontology analyses revealed enrichment for human speech- and language-related functions in males only, consistent with the sexual dimorphism of song learning in this species. Fewer such targets were found in juveniles relative to adults, suggesting an expansion of this regulatory network with maturation. The fewest speech-related targets were found in the singing condition, consistent with the well-documented singing-driven down-regulation of FoxP2 in the songbird striatum. Conclusions: Overall, these data provide an initial catalog of the regulatory landscape of FoxP2 in an avian vocal learner, offering dozens of target genes for future study and providing insight into the molecular underpinnings of vocal learning.

11.
Artículo en Inglés | MEDLINE | ID: mdl-39005228

RESUMEN

Developmental environmental stressors can have instructive effects on an organism's phenotype. This developmental plasticity can prepare organisms for potentially stressful future environments, circumventing detrimental effects on fitness. However, the physiological mechanisms underlying such adaptive plasticity are understudied, especially in vertebrates. We hypothesized that captive male zebra finches (Taeniopygia castanotis) exposed to a mild heat conditioning during development would acquire a persisting thermotolerance, and exhibit increased heat-shock protein (HSP) levels associated with a decrease in oxidative damage when exposed to a high-intensity stressor in adulthood. To test this, we exposed male finches to a prolonged mild heat conditioning (38°C) or control (22°C) treatment as juveniles. Then in a 2 × 2 factorial manner, these finches were exposed to a high heat stressor (42°C) or control (22°C) treatment as adults. Following the adult treatment, we collected testes and liver tissue and measured HSP70, HSP90, and HSP60 protein levels. In the testes, finches exhibited lower levels of HSP90 and HSP60 when exposed to the high heat stressor in adulthood if they were exposed to the mild heat conditioning as juveniles. In the liver, finches exposed to the high heat stressor in adulthood had reduced HSP90 and HSP60 levels, regardless of whether they were conditioned as juveniles. In some cases, elevated testes HSP60 levels were associated with increased liver oxidative damage and diminishment of a condition-dependent trait, indicating potential stress-induced tradeoffs. Our results indicate that a mild conditioning during development can have persisting effects on HSP expression and acquired thermotolerance.

12.
Environ Pollut ; 358: 124461, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38964643

RESUMEN

Identifying key molecular pathways and genes involved in the response to urban pollutants is an important step in furthering our understanding of the impact of urbanisation on wildlife. The expansion of urban habitats and the associated human-introduced environmental changes are considered a global threat to the health and persistence of humans and wildlife. The present study experimentally investigates how short-term exposure to three urban-related pollutants -soot, artificial light at night (ALAN) and traffic noise-affects transcriptome-wide gene expression in livers from captive female zebra finches (Taeniopygia guttata). Compared to unexposed controls, 17, 52, and 28 genes were differentially expressed in soot, ALAN and noise-exposed birds, respectively. In soot-exposed birds, the enriched gene ontology (GO) terms were associated with a suppressed immune system such as interferon regulating genes (IRGs) and responses to external stimuli. For ALAN-exposed birds, enriched GO terms were instead based on downregulated genes associated with detoxification, redox, hormonal-, and metabolic processes. Noise exposure resulted in downregulation of genes associated with the GO terms: cellular responses to substances, catabolic and cytokine responses. Among the individually differentially expressed genes (DEGs), soot led to an increased expression of genes related to tumour progression. Likewise, ALAN revealed an upregulation of multiple genes linked to different cancer types. Both sensory pollutants (ALAN and noise) led to increased expression of genes linked to neuronal function. Interestingly, noise caused upregulation of genes associated with serotonin regulation and function (SLC6A4 and HTR7), which previous studies have shown to be under selection in urban birds. These outcomes indicate that short-term exposure to the three urban pollutants perturbate the liver transcriptome, but most often in different ways, which highlights future studies of multiple-stress exposure and their interactive effects, along with their long-term impacts for urban-dwelling wildlife.


Asunto(s)
Perfilación de la Expresión Génica , Hígado , Transcriptoma , Animales , Hígado/metabolismo , Femenino , Ruido/efectos adversos , Pinzones/genética , Contaminantes Ambientales , Luz
13.
Sci Rep ; 14(1): 16248, 2024 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009624

RESUMEN

Psyllid species, including the potato psyllid (PoP) Bactericera cockerelli (Sulc) (Triozidae) serve as host and vector of "Candidatus Liberibacter spp." ("Ca. Liberibacter"), which also infects diverse plant hosts, including citrus and tomato. Psyllid transmission of "Ca. Liberibacter" is circulative and propagative. The time of "Ca. Liberibacter" acquisition and therefore vector life stage most competent for bacterial transmission varies by pathosystems. Here, the potato psyllid-"Ca. Liberibacter solanacearum" (CLso) pathosystem was investigated to dissect CLso-prophage interactions in the tomato plant and PoP-psyllid host by real-time quantitative reverse transcriptase amplification of CLso genes/loci with predicted involvement in host infection and psyllid-CLso transmission. Genes/loci analyzed were associated with (1) CLso-adhesion, -invasion, -pathogenicity, and -motility, (2) prophage-adhesion and pathogenicity, and (3) CLso-lysogenic cycle. Relative gene expression was quantified by qRT-PCR amplification from total RNA isolated from CLso-infected 1st-2nd and 4th-5th nymphs and teneral adults and CLso-infected tomato plants in which CLso infection is thought to occur without SC1-SC2 replication. Gene/loci expression was host-dependent and varied with the psyllid developmental stage. Loci previously associated with repressor-anti-repressor regulation in the "Ca Liberibacter asiaticus"-prophage pathosystem, which maintains the lysogenic cycle in Asian citrus psyllid Diaphorina citri, were expressed in CLso-infected psyllids but not in CLso-infected tomato plants.


Asunto(s)
Hemípteros , Enfermedades de las Plantas , Profagos , Solanum lycopersicum , Animales , Hemípteros/microbiología , Profagos/genética , Solanum lycopersicum/microbiología , Enfermedades de las Plantas/microbiología , Solanum tuberosum/microbiología , Solanum tuberosum/parasitología , Insectos Vectores/microbiología , Rhizobiaceae/genética , Regulación Bacteriana de la Expresión Génica , Estadios del Ciclo de Vida/genética
14.
bioRxiv ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38979160

RESUMEN

Sensory experience during development has lasting effects on perception and neural processing. Exposing animals to artificial stimuli early in life influences the tuning and functional organization of the auditory cortex, but less is known about how the rich acoustical environments experienced by vocal communicators affect the processing of complex vocalizations. Here, we show that in zebra finches (Taeniopygia guttata), a colonial-breeding songbird species, exposure to a naturalistic social-acoustical environment during development has a profound impact on cortical-level auditory responses to conspecific song. Compared to birds raised by pairs in acoustic isolation, birds raised in a breeding colony had higher average firing rates, selectivity, and discriminability, especially in the narrow-spiking, putatively inhibitory neurons of a higher-order auditory area, the caudomedial nidopallium (NCM). Neurons in colony-reared birds were also less correlated in their tuning and more efficient at encoding the spectrotemporal structure of conspecific song. These results suggest that the auditory cortex adapts to noisy, complex acoustical environments by strengthening inhibitory circuitry, functionally decoupling excitatory neurons while maintaining overall excitatory-inhibitory balance.

15.
Sci Rep ; 14(1): 17148, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39060369

RESUMEN

The Internet of Things (IoT) permeates various sectors, including healthcare, smart cities, and agriculture, alongside critical infrastructure management. However, its susceptibility to malware due to limited processing power and security protocols poses significant challenges. Traditional antimalware solutions fall short in combating evolving threats. To address this, the research work developed a feature selection-based classification model. At first stage, a preprocessing stage enhances dataset quality through data smoothing and consistency improvement. Feature selection via the Zebra Optimization Algorithm (ZOA) reduces dimensionality, while a classification phase integrates the Graph Attention Network (GAN), specifically the Dual-channel GAN (DGAN). DGAN incorporates Node Attention Networks and Semantic Attention Networks to capture intricate IoT device interactions and detect anomalous behaviors like botnet activity. The model's accuracy is further boosted by leveraging both structural and semantic data with the Sooty Tern Optimization Algorithm (STOA) for hyperparameter tuning. The proposed STOA-DGAN model achieves an impressive 99.87% accuracy in botnet activity classification, showcasing robustness and reliability compared to existing approaches.

16.
Elife ; 122024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38959057

RESUMEN

Songbirds' vocal mastery is impressive, but to what extent is it a result of practice? Can they, based on experienced mismatch with a known target, plan the necessary changes to recover the target in a practice-free manner without intermittently singing? In adult zebra finches, we drive the pitch of a song syllable away from its stable (baseline) variant acquired from a tutor, then we withdraw reinforcement and subsequently deprive them of singing experience by muting or deafening. In this deprived state, birds do not recover their baseline song. However, they revert their songs toward the target by about 1 standard deviation of their recent practice, provided the sensory feedback during the latter signaled a pitch mismatch with the target. Thus, targeted vocal plasticity does not require immediate sensory experience, showing that zebra finches are capable of goal-directed vocal planning.


Asunto(s)
Pinzones , Objetivos , Vocalización Animal , Animales , Vocalización Animal/fisiología , Pinzones/fisiología , Masculino
17.
Front Robot AI ; 11: 1386968, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38947861

RESUMEN

The performance of the robotic manipulator is negatively impacted by outside disturbances and uncertain parameters. The system's variables are also highly coupled, complex, and nonlinear, indicating that it is a multi-input, multi-output system. Therefore, it is necessary to develop a controller that can control the variables in the system in order to handle these complications. This work proposes six control structures based on neural networks (NNs) with proportional integral derivative (PID) and fractional-order PID (FOPID) controllers to operate a 2-link rigid robot manipulator (2-LRRM) for trajectory tracking. These are named as set-point-weighted PID (W-PID), set-point weighted FOPID (W-FOPID), recurrent neural network (RNN)-like PID (RNNPID), RNN-like FOPID (RNN-FOPID), NN+PID, and NN+FOPID controllers. The zebra optimization algorithm (ZOA) was used to adjust the parameters of the proposed controllers while reducing the integral-time-square error (ITSE). A new objective function was proposed for tuning to generate controllers with minimal chattering in the control signal. After implementing the proposed controller designs, a comparative robustness study was conducted among these controllers by altering the initial conditions, disturbances, and model uncertainties. The simulation results demonstrate that the NN+FOPID controller has the best trajectory tracking performance with the minimum ITSE and best robustness against changes in the initial states, external disturbances, and parameter uncertainties compared to the other controllers.

18.
Am Nat ; 204(1): 73-95, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38857346

RESUMEN

AbstractDevelopmental plasticity allows organisms to increase the fit between their phenotype and their early-life environment. The extent to which such plasticity also enhances adult fitness is not well understood, however, particularly when early-life and adult environments differ substantially. Using a cross-factorial design that manipulated diet at two life stages, we examined predictions of major hypotheses-silver spoon, environmental matching, and thrifty phenotype-concerning the joint impacts of early-life and adult diets on adult morphology/display traits, survival, and reproductive allocation. Overall, results aligned with the silver spoon hypothesis, which makes several predictions based on the premise that development in poor-quality environments constrains adult performance. Males reared and bred on a low-protein diet had lower adult survivorship than other male treatment groups; females' survivorship was higher than males' and not impacted by early diet. Measures of allocation to reproduction primarily reflected breeding diet, but where natal diet impacted reproduction, results supported the silver spoon. Both sexes showed reduced expression of display traits when reared on a low-protein diet. Results accord with other studies in supporting the relevance of the silver spoon hypothesis to birds and point to significant ramifications of sex differences in early-life viability selection on the applicability/strength of silver spoon effects.


Asunto(s)
Pinzones , Reproducción , Animales , Masculino , Femenino , Pinzones/fisiología , Longevidad , Dieta/veterinaria , Fenotipo , Dieta con Restricción de Proteínas
19.
Sci Rep ; 14(1): 13787, 2024 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877207

RESUMEN

Cultural and genetic inheritance combine to enable rapid changes in trait expression, but their relative importance in determining trait expression across generations is not clear. Birdsong is a socially learned cognitive trait that is subject to both cultural and genetic inheritance, as well as being affected by early developmental conditions. We sought to test whether early-life conditions in one generation can affect song acquisition in the next generation. We exposed one generation (F1) of nestlings to elevated corticosterone (CORT) levels, allowed them to breed freely as adults, and quantified their son's (F2) ability to copy the song of their social father. We also quantified the neurogenetic response to song playback through immediate early gene (IEG) expression in the auditory forebrain. F2 males with only one corticosterone-treated parent copied their social father's song less accurately than males with two control parents. Expression of ARC in caudomedial nidopallium (NCM) correlated with father-son song similarity, and patterns of expression levels of several IEGs in caudomedial mesopallium (CMM) in response to father song playback differed between control F2 sons and those with a CORT-treated father only. This is the first study to demonstrate that developmental conditions can affect social learning and neurogenetic responses in a subsequent generation.


Asunto(s)
Corticosterona , Aprendizaje , Vocalización Animal , Animales , Vocalización Animal/fisiología , Masculino , Aprendizaje/fisiología , Corticosterona/metabolismo , Femenino , Pinzones/fisiología , Prosencéfalo/metabolismo , Prosencéfalo/fisiología , Genes Inmediatos-Precoces
20.
Med Sci (Basel) ; 12(2)2024 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-38804381

RESUMEN

Phospholipidosis is a rare disorder which consists of an excessive intracellular accumulation of phospholipids and the appearance of zebra bodies or lamellar bodies when looking at them using electron microscopy. This disease is associated with certain genetic diseases or is secondary to drugs or toxins. Drug-induced phospholipidosis encompasses many types of pharmaceuticals, most notably chloroquine, amiodarone or ciprofloxacin. Clinically and histologically, renal involvement can be highly variable, with the diagnosis not being made until the zebra bodies are seen under an electron microscope. These findings may require genetic testing to discount Fabry disease, as its histological findings are indistinguishable. Most of the chemicals responsible are cationic amphiphilic drugs, and several mechanisms have been hypothesized for the formation of zebra bodies and their pathogenic significance. However, the relationship between drug toxicity and phospholipid accumulation, zebra bodies and organ dysfunction remains enigmatic, as do the renal consequences of drug withdrawal. We present, to our knowledge, the first case report of acute renal injury with a monoclonal gammopathy of renal significance, lesions, and sclerodermiform syndrome, with zebra bodies that were associated with the initiation of a hydroxychloroquine and amiodarone treatment, as an example of drug-induced-phospholipidosis.


Asunto(s)
Amiodarona , Hidroxicloroquina , Fosfolípidos , Humanos , Lesión Renal Aguda/inducido químicamente , Amiodarona/efectos adversos , Hidroxicloroquina/efectos adversos , Hidroxicloroquina/uso terapéutico , Lipidosis/inducido químicamente , Paraproteinemias/inducido químicamente , Femenino , Anciano
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