Prime Model Research Articles

Visuomotor and motorvisual priming with different types of set-level congruency: evidence in support of ideomotor theory, and the planning and control model (PCM)

Perception can prime action (visuomotor priming), and action can prime perception (motorvisual priming). According to ideomotor theory both effects rely on the overlap of mental representations between perception and action. This implies that both effects get more pronounced the more features they share. We tested this hypothesis by employing in a motorvisual (Exp. 1) and in a visuomotor (Exp. 2) setting, three different pairs of left/right target stimuli (hand pictures, arrows, and words) varying in how strongly they overlap with the pair of left/right responses. For two stimulus pairs (hands and words) the hypothesis was confirmed: hand pictures share more features with the responses than words, consequently hand pictures produced a stronger visuomotor and a stronger motorvisual priming effect than words. However, arrow stimuli showed a different pattern: the temporal dynamics of both priming effects, as well as the direction of the effect seen in motorvisual priming, were significant but opposite to that of the hand and word stimuli. This suggests that the arrows’ representations were not involved in ideomotor processes, and we propose instead that they were represented in a spatial or scalar fashion, outside the representations assumed in ideomotor theory. The results are discussed in the context of ideomotor theory, and the planning and control model of motorvisual priming.

Protocols for the delivery of small molecules to the two-spotted spider mite, Tetranychus urticae

The two-spotted spider mite, Tetranychus urticae, is a chelicerate herbivore with an extremely wide host range and an extraordinary ability to develop pesticide resistance. Due to its responsiveness to natural and synthetic xenobiotics, the spider mite is becoming a prime pest herbivore model for studies of the evolution of host range, plant-herbivore interactions and mechanisms of xenobiotic resistance. The spider mite genome has been sequenced and its transcriptional responses to developmental and various biotic and abiotic cues have been documented. However, to identify biological and evolutionary roles of T. urticae genes and proteins, it is necessary to develop methods for the efficient manipulation of mite gene function or protein activity. Here, we describe protocols developed for the delivery of small molecules into spider mites. Starting with mite maintenance and the preparation of the experimental mite populations of developmentally synchronized larvae and adults, we describe 3 methods for delivery of small molecules including artificial diet, leaf coating, and soaking. The presented results define critical steps in these methods and demonstrate that they can successfully deliver tracer dyes into mites. Described protocols provide guidelines for high-throughput setups for delivery of experimental compounds that could be used in reverse genetics platforms to modulate gene expression or protein activity, or for screens focused on discovery of new molecules for mite control. In addition, described protocols could be adapted for other Tetranychidae and related species of economic importance such as Varroa, dust and poultry mites.

Quasiminimal abstract elementary classes

We propose the notion of a quasiminimal abstract elementary class (AEC). This is an AEC satisfying four semantic conditions: countable L\"owenheim-Skolem-Tarski number, existence of a prime model, closure under intersections, and uniqueness of the generic orbital type over every countable model. We exhibit a correspondence between Zilber's quasiminimal pregeometry classes and quasiminimal AECs: any quasiminimal pregeometry class induces a quasiminimal AEC (this was known), and for any quasiminimal AEC there is a natural functorial expansion that induces a quasiminimal pregeometry class. We show in particular that the exchange axiom is redundant in Zilber's definition of a quasiminimal pregeometry class.

Effective prime uniqueness

Assuming the obvious definitions (see paper) we show the a decidable model that is prime is also atomic. This implies that two prime (decidable) models are computably isomorphic. This is in contrast to the theorem that there are two decidable models which are not computably isomorphic. The implications of this work in reverse mathematics is that effectively prime implies atomic holds in topped models. But due to an observation of David Belanger, effectively prime implies atomic fails for some Scott sets. The reserve mathematical strength of Prime Uniqueness remains open.

Rocking of rigid block on nonlinear flexible foundation

The two prime models used currently to describe rocking of rigid bodies, the Housner’s model and the Winkler foundation model, can capture some of the salient features of the physics of this important problem. These two models involve either null or linear interaction between the block and the foundation.Hopefully, some additional aspects of the problem can be captured by an enhanced nonlinear model for the base-foundation interaction. In this regard, what it is adopted in this paper is the Hunt and Crossley’s nonlinear impact force model in which the impact/contact force is represented by springs in parallel with nonlinear dampers. In this regard, a proper mathematical formulation is developed accounting for the possibility of uplifting in the case of strong excitation. Further, an averaging procedure has been developed to expeditiously derive the steady state response amplitude in case of harmonic base excitation. The analytical study is supplemented by experimental tests developed in the Laboratory of Experimental Dynamics at the University of Palermo, Italy. In this context, because of the obvious relevance for historical monuments, free-rocking tests are presented for several marble-block geometries on both rigid and flexible foundations. Numerical vis-à-vis experimental data are examined, showing that the proposed nonlinear model is sufficiently versatile to capture additional aspects of the physics of the problem even for quite soft foundation materials.

Genome-wide survey of switchgrass NACs family provides new insights into motif and structure arrangements and reveals stress-related and tissue-specific NACs

NAC proteins comprise of a plant-specific transcription factor (TF) family and play important roles in plant development and stress responses. Switchgrass (Panicum virgatum) is the prime candidate and model bioenergy grass across the world. Excavating agronomically valuable genes is important for switchgrass molecular breeding. In this study, a total of 251 switchgrass NAC (PvNACs) family genes clustered into 19 subgroups were analyzed, and those potentially involved in stress response or tissue-specific expression patterns were pinpointed. Specifically, 27 PvNACs were considered as abiotic stress-related including four membrane-associated ones. Among 40 tissue-specific PvNACs expression patterns eight factors were identified that might be relevant for lignin biosynthesis and/or secondary cell wall formation. Conserved functional domains and motifs were also identified among the PvNACs and potential association between these motifs and their predicted functions were proposed, that might encourage experimental studies to use PvNACs as possible targets to improve biomass production and abiotic stress tolerance.

The onset and time course of semantic priming during rapid recognition of visual words.

In 2 experiments, we assessed the effects of response latency and task-induced goals on the onset and time course of semantic priming during rapid processing of visual words as revealed by ocular response tasks. In Experiment 1 (ocular lexical decision task), participants performed a lexical decision task using eye movement responses on a sequence of 4 words. In Experiment 2, the same words were encoded for an episodic recognition memory task that did not require a metalinguistic judgment. For both tasks, survival analyses showed that the earliest observable effect (divergence point [DP]) of semantic priming on target-word reading times occurred at approximately 260 ms, and ex-Gaussian distribution fits revealed that the magnitude of the priming effect increased as a function of response time. Together, these distributional effects of semantic priming suggest that the influence of the prime increases when target processing is more effortful. This effect does not require that the task include a metalinguistic judgment; manipulation of the task goals across experiments affected the overall response speed but not the location of the DP or the overall distributional pattern of the priming effect. These results are more readily explained as the result of a retrospective, rather than a prospective, priming mechanism and are consistent with compound-cue models of semantic priming. (PsycINFO Database Record

Comparing different kinds of words and word-word relations to test an habituation model of priming

Huber and O'Reilly (2003) proposed that neural habituation exists to solve a temporal parsing problem, minimizing blending between one word and the next when words are visually presented in rapid succession. They developed a neural dynamics habituation model, explaining the finding that short duration primes produce positive priming whereas long duration primes produce negative repetition priming. The model contains three layers of processing, including a visual input layer, an orthographic layer, and a lexical-semantic layer. The predicted effect of prime duration depends both on this assumed representational hierarchy and the assumption that synaptic depression underlies habituation. The current study tested these assumptions by comparing different kinds of words (e.g., words versus non-words) and different kinds of word-word relations (e.g., associative versus repetition). For each experiment, the predictions of the original model were compared to an alternative model with different representational assumptions. Experiment 1 confirmed the prediction that non-words and inverted words require longer prime durations to eliminate positive repetition priming (i.e., a slower transition from positive to negative priming). Experiment 2 confirmed the prediction that associative priming increases and then decreases with increasing prime duration, but remains positive even with long duration primes. Experiment 3 replicated the effects of repetition and associative priming using a within-subjects design and combined these effects by examining target words that were expected to repeat (e.g., viewing the target word ‘BACK' after the prime phrase ‘back to'). These results support the originally assumed representational hierarchy and more generally the role of habituation in temporal parsing and priming.

(132) Microglia promote pain plasticity in males while CGRP promotes pain plasticity in females in the hyperalgesic priming model

(132) Microglia promote pain plasticity in males while CGRP promotes pain plasticity in females in the hyperalgesic priming model

(133) BDNF/TrkB signaling in the hyperalgesic priming model: temporal, sex and species differences

(133) BDNF/TrkB signaling in the hyperalgesic priming model: temporal, sex and species differences

A note on prime models in weakly o‐minimal structures

Let be a weakly o‐minimal structure with the strong cell decomposition property. In this note, we show that the canonical o‐minimal extension of is the unique prime model of the full first order theory of over any set . We also show that if two weakly o‐minimal structures with the strong cell decomposition property are isomorphic then, their canonical o‐minimal extensions are isomorphic too. Finally, we show the uniqueness of the prime models in a complete weakly o‐minimal theory with prime models.

Shelah's eventual categoricity conjecture in universal classes: Part I

We prove: Theorem 0.1Let K be a universal class. If K is categorical in cardinals of arbitrarily high cofinality, then K is categorical on a tail of cardinals.The proof stems from ideas of Adi Jarden and Will Boney, and also relies on a deep result of Shelah. As opposed to previous works, the argument is in ZFC and does not use the assumption of categoricity in a successor cardinal. The argument generalizes to abstract elementary classes (AECs) that satisfy a locality property and where certain prime models exist. Moreover assuming amalgamation we can give an explicit bound on the Hanf number and get rid of the cofinality restrictions:Theorem 0.2Let K be an AEC with amalgamation. Assume that K is fullyLS(K)-tame and short and has primes over sets of the formM∪{a}. WriteH2:=ℶ(2ℶ(2LS(K))+)+. If K is categorical in aλ>H2, then K is categorical in allλ′≥H2.

A stochastic model of active zone material mediated synaptic vesicle docking and priming at resting active zones

Synaptic vesicles (SVs) fuse with the presynaptic membrane (PM) at specialized regions called active zones for synaptic transmission. SVs are associated with dense aggregates of macromolecules called active zone material (AZM) that has been thought to be involved in SV release. However, its role has recently begun to be elucidated. Several morphological studies proposed distinctively different AZM mediated SV docking and priming models: sequential and concurrent SV docking/priming. To explore ways to reconcile the contradictory models we develop a stochastic AZM mediated SV docking and priming model. We assume that the position of each connection site of the AZM macromolecules on their SV, directly linking the SV with the PM, varies by random shortening and lengthening of the macromolecules at resting active zones. We also perform computer simulations of SVs near the PM at resting active zones, and the results show that the distribution of the AZM connection sites can significantly affect the SV’s docking efficiency and distribution of its contact area with the PM, thus priming and that the area correlates with the shape of the SVs providing a way to account for seemingly irreconcilable observations reported about the spatial relationship of SVs with the PM at active zones.

Hyperalgesic priming (type II) induced by repeated opioid exposure: maintenance mechanisms.

We previously developed a model of opioid-induced neuroplasticity in the peripheral terminal of the nociceptor that could contribute to opioid-induced hyperalgesia, type II hyperalgesic priming. Repeated administration of mu-opioid receptor (MOR) agonists, such as DAMGO, at the peripheral terminal of the nociceptor, induces long-lasting plasticity expressed, prototypically as opioid-induced hyperalgesia and prolongation of prostaglandin E2-induced hyperalgesia. In this study, we evaluated the mechanisms involved in the maintenance of type II priming. Opioid receptor antagonist, naloxone, induced hyperalgesia in DAMGO-primed paws. When repeatedly injected, naloxone-induced hyperalgesia, and hyperalgesic priming, supporting the suggestion that maintenance of priming involves changes in MOR signaling. However, the knockdown of MOR with oligodeoxynucleotide antisense did not reverse priming. Mitogen-activated protein kinase and focal adhesion kinase, which are involved in the Src signaling pathway, previously implicated in type II priming, also inhibited the expression, but not maintenance of priming. However, when Src and mitogen-activated protein kinase inhibitors were coadministered, type II priming was reversed, in male rats. A second model of priming, latent sensitization, induced by complete Freund's adjuvant was also reversed, in males. In females, the inhibitor combination was only able to inhibit the expression and maintenance of DAMGO-induced priming when knockdown of G-protein-coupled estrogen receptor 30 (GPR30) in the nociceptor was performed. These findings demonstrate that the maintenance of DAMGO-induced type II priming, and latent sensitization is mediated by an interaction between, Src and MAP kinases, which in females is GPR30 dependent.

Of fish and mirrors: Fluoxetine disrupts aggression and learning for social rewards

Aggressive signaling is a key social behavior of male Siamese fighting fish (Betta splendens). Successfully establishing a territory and defending it from intruders has direct fitness effects, making Betta splendens a prime model for studies examining the biological underpinnings of aggressive behavior. Current research has outlined serotonin transporter pathways as one key component for the engagement and coordination of aggressive behavior in Betta splendens. Using the selective serotonin reuptake inhibitor fluoxetine, we examined the impact of 10μmol exposures on associative learning and aggression between mirror and conspecific social reinforcers. Our results provide clear evidence that exposure to fluoxetine reduces aggression and impairs learning independent of social reinforce type. In addition, our results provide support for motor inhibition of aggressive behavior as the main behavioral mechanism of action for fluoxetine. Placed within the broader context of behavioral syndromes, our results, along with others, implicate serotonergic pathways as a key biological correlate of the bold-aggressive phenotype.

Priming and adaptation in native speakers and second-language learners

Native speakers show rapid adjustment of their processing strategies and preferences on the basis of the structures they have recently encountered. The present study investigated the nature of priming and adaptation in second-language (L2) speakers and, more specifically, whether similar mechanisms underlie L2 and native language adaptation. Native English speakers and Korean L2 learners of English completed a written priming study probing the use of double object and prepositional phrase datives. Both groups showed cumulative adaptation effects for both types of dative, which was stronger for the structure that was initially less frequent to them (prepositional phrase datives for the native English speakers, and double object datives for the L2 learners). This supports models of priming that incorporate frequency-based modulation of long-lasting activation of structures. L2 learners and native speakers use similar processing mechanisms; differences in adaptation can be accounted for by differences in the relative frequency of structures.

Generic orbits and type isolation in the Gurarij space

We study the question of when the space of embeddings of a separable Banach space $E$ into the separable Gurarij space $\mathbf G$ admits a generic orbit under the action of the linear isometry group of $\mathbf G$. The question is recast in model-theoretic terms, namely type isolation and the existence of prime models. We characterise isolated types over $E$ using tools from convex analysis. We show that if the set of isolated types over $E$ is dense, then a dense $G\_\delta$ orbit exists, and otherwise all orbits are meagre. We then study some (families of) examples with respect to this dichotomy. We also point out that the class of Gurarij spaces is the class of models of an $\aleph\_0$-categorical theory with quantifier elimination, and calculate the density character of the space of types over $E$, answering a question of Avil{\'e}s et al.

“Every New Land Demands Blood”: ‘Nature’ and the Justification of Frontier Violence in Hell on Wheels

This paper demonstrates how AMC’s TV show Hell on Wheels portrays the ideological force of nature to justify violence in frontier mythology. After a short look into the historical and ongoing relevance of frontier mythology in US culture, I will argue for its ideological reliance on nature. The following chapter will provide a theoretical background on social Darwinism, determinism, and scientism. I will then analyze how these relationships are examined in Hell on Wheels. First, as Thomas Durant’s social Darwinist monologue is paralleled with imagery that challenges the providential myth of Manifest Destiny, the show reveals that both ideologies equally replace human responsibility with a quasi-evolutionary rhetoric of inevitable progress. Second, the Swede’s deterministic notions of nature demonstrate the mythical power of the natural environment and evolutionary biology, which can easily assume Manifest Destiny’s divine authority as a justification for violence. Finally, the Swede’s and Reverend Cole’s discursive replacement of God with blood signifies a shift from religion to a redemptive scientism, in which science purports not only to explain but also to justify the violence of westward expansion. In these renditions, nature is variably utilized as the prime model for social behavior, as the ultimate victor over culture, and as the final authority whose imperatives are intelligible only through science.

How far is mitigation of Russian gas dependency possible through energy efficiency and renewable policies assuming different gas market structures?

This paper presents the results of a coordinated modelling assessment that incorporates European energy efficiency and renewable policies with two potential gas market scenarios. First, the impact of EU energy efficiency and renewable policies on natural gas demand is calculated using the PRIMES model 2014 Baseline projection, the Fraunhofer ISI Low Policy Intensity Energy Efficiency scenario, and the Green-X model for renewable deployment. Next, the effect of these policies on the natural gas markets is assessed, using the European Gas Market Model. The model tests scenarios for different positions on long-term gas contracts with Russia assuming different stages of European gas infrastructure development. The findings show that dependency on Russian natural gas can be reduced to low levels without triggering a significant increase in natural gas prices for any single EU member country. In an extreme scenario whereby energy efficiency savings, higher renewable energy sources deployment and the assumed positive gas market developments take place simultaneously, gas cost savings can reach as high as 37%. Benefits arise not only in the most recent round of EU Member States (12 MS) targeted in the study, but are visible across most EU gas markets. This underlines the interlinkages of the whole EU gas market, and the results suggest that security of gas supply is not only a challenge for new Member States, but in the broader European markets.

Identification of the fitness determinants of budding yeast on a natural substrate.

The budding yeasts are prime models in genomics and cell biology, but the ecological factors that determine their success in non-human-associated habitats is poorly understood. In North America Saccharomyces yeasts are present on the bark of deciduous trees, where they feed on bark and sap exudates. In the North East, Saccharomyces paradoxus is found on maples, which makes maple sap a natural substrate for this species. We measured growth rates of S. paradoxus natural isolates on maple sap and found variation along a geographical gradient not explained by the inherent variation observed under optimal laboratory conditions. We used a functional genomic screen to reveal the ecologically relevant genes and conditions required for optimal growth in this substrate. We found that the allantoin degradation pathway is required for optimal growth in maple sap, in particular genes necessary for allantoate utilization, which we demonstrate is the major nitrogen source available to yeast in this environment. Growth with allantoin or allantoate as the sole nitrogen source recapitulated the variation in growth rates in maple sap among strains. We also show that two lineages of S. paradoxus display different life-history traits on allantoin and allantoate media, highlighting the ecological relevance of this pathway.