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Inflammation, over-reacting innate immunity, and CD4+ T cell depletion are hallmarks of HIV-1 infection. Self-DNA is usually not considered in the context of HIV-1-associated inflammation, although self-DNA contributes to inflammation in diverse pathologies, including autoimmune diseases, cancer, multiorgan failure after trauma, and even virus infections. Cells undergoing HIV-1-associated pyroptotic bystander cell death release self-DNA and other damage-associated molecular patterns (DAMPs), including chaperones and histones. In complexes with such DAMPs or extracellular vesicles, self-DNA gains immunogenic potential and becomes accessible to intracellular DNA sensors. Therefore, we hypothesize that self-DNA can contribute to HIV-1-associated inflammation. Self-DNA might not only drive HIV-1-associated 'inflamm-ageing' but also provide new opportunities for 'shock and kill' strategies aimed at eliminating latent HIV-1. Stressed or dying cells release immunogenic self-DNA. Cytoplasmic self-DNA and its exchange among cells primes innate immunity and circulating DNA can trigger systemic inflammation and autoimmune diseases. HIV-1 primes DNA-sensing, favours DNA damage, and triggers bystander cell pyroptosis and the subsequent release of cellular content, including self-DNA and other DAMPs. Extracellular self-DNA gains immunogenic properties when bound to DAMPs. Self-DNA might not only trigger inflammatory feedforward-loops in HIV-1-infected individuals but also open up avenues for optimizing shock and kill strategies for HIV elimination. [ABSTRACT FROM AUTHOR]

Fungi emit a diverse blend of volatile organic compounds (VOCs) that mediate multiple fungus-fungus interactions. Plants emit VOCs as well, which can serve as resistance-inducing signals but might also act as direct resistance agents. We screened 22 VOCs that are emitted from infected plants for putative inhibitory effects on three fungal phytopathogens: Colletotrichum lindemuthianum , Fusarium oxysporum and Botrytis cinerea . The growth of all three fungi was significantly inhibited when the mycelia were exposed to an atmosphere containing nonanal, (+)-carvone, citral, trans -2-decenal, L -linalool, or nerolidol. Eugenol completely inhibited the growth of all three fungi, and 1-octen-3-ol, nonanal, 2,6-dimethyl-2,4,6-octatriene, citral, α-terpineol and trans -2-decanal inhibited at least one fungus completely. Most of these VOCs are also emitted from fungi. We conclude that antagonistic fungus-fungus and plant-fungus interactions might share common mechanisms and that plant VOCs can function as resistance agents that fungal pathogens must overcome for successful infection. [ABSTRACT FROM AUTHOR]

Phaseolus lunatus (lima bean) has been a model organism to understand direct and indirect defenses against herbivores. We investigated the identity and diversity of endophytic fungi associated with young, mature and old leaves of lima bean in its natural environment. We recovered 758 isolates that were identified and classified in 142 fungal species from 66 genera, with Curvularia , Fusarium , Phomopsis , Alternaria and Colletotrichum being the most abundant and diverse Ascomycota genera. Our data revealed that species richness and diversity increased with leaf age, this factor being also important for the structure of the endophytic community. The occurrence patterns of fungal species was highly heterogeneous among leaves, and only fourteen species were recovered from all three foliar ages investigated. In vitro dual assays between endophytes and the plant pathogen Colletotrichum lindemuthianum revealed that most endophytes tested can inhibit the growth of this pathogen, suggesting their potential as biocontrol agents. [ABSTRACT FROM AUTHOR]

Plants perceive injury and herbivore attack via the recognition of damage-associated molecular patterns (DAMPs) and herbivore-associated molecular patterns (HAMPs). Although HAMPs in particular are cues that can indicate the presence of a specific enemy, the application of pure DAMPs or HAMPs frequently activates general downstream responses: membrane depolarization, Ca 2+ influxes, oxidative stress, MAPKinase activation and octadecanoid signaling at the molecular level, and the expression of digestion inhibitors, cell wall modifications and other general defenses at the phenotypic level. We discuss the relative benefits of perceiving the non-self versus the damaged-self and of specific versus non-specific responses and suggest that the perception of a complex mixture of DAMPs and HAMPs triggers fine-tuned plant responses. DAMPs such as extracellular ATP (eATP), cell wall fragments, signaling peptides, herbivore-induced volatile organic compounds (HI-VOCs) and eDNA hold the key for a more complete understanding of how plants perceive that and by whom they are attacked. [ABSTRACT FROM AUTHOR]

Volatile compounds and extrafloral nectar are common defenses of wild plants; however, in crops they bear an as-yet underused potential for biological control of pests and diseases. Odor emission and nectar secretion are multigene traits in wild plants, and thus form difficult targets for breeding. Furthermore, domestication has changed the capacity of crops to express these traits. We propose that breeding crops for an enhanced capacity for tritrophic interactions and volatile-mediated direct resistance to herbivores and pathogens can contribute to environmentally-friendly and sustainable agriculture. Natural plant volatiles with antifungal or repellent properties can serve as direct resistance agents. In addition, volatiles mediating tritrophic interactions can be combined with nectar-based food rewards for carnivores to boost indirect plant defense. [ABSTRACT FROM AUTHOR]

Men outperform women in the Mental Rotation Test (MRT) by about one standard deviation. The present study replicated a gender belief account [Moè, A., & Pazzaglia, F. (2006). Following the instructions! Effects of gender beliefs in mental rotation. Learning and Individual Differences, 16, 369–377.] for (part of) this effect. A sample of 300 adults, whose gender beliefs about mental rotation were manipulated experimentally (instructions given: men are better, women are better, or no gender differences exist) had to complete the MRT. Artificially induced gender beliefs affected performance and guessing behavior differently in relation to gender. Women''s performance followed the gender belief induction but their guessing behavior remained unaffected. Men''s performance, however, remained unaffected but their guessing behavior followed the gender belief induction. These findings suggest that gender beliefs affect men and women differently, and they also suggest that a gender belief account cannot (fully) explain gender differences in mental rotation performance. [Copyright &y& Elsevier]

Host ranges are commonly quantified to classify herbivores and plant pathogens as either generalists or specialists. Here, we summarize patterns and mechanisms in the interactions of plants with these enemies along different axes of specificity. We highlight the many dimensions within which plant enemies can specify and consider the underlying ecological, evolutionary and molecular mechanisms. Host resistance traits and enemy effectors emerge as central players determining host utilization and thus host range. Finally, we review approaches to studying the causes and consequences of variation in the specificity of plant–enemy interactions. Knowledge of the molecular mechanisms that determine host range is required to understand host shifts, and evolutionary transitions among specialist and generalist strategies, and to predict potential host ranges of pathogens and herbivores. [Copyright &y& Elsevier]

Nectar contains water, sugars and amino acids to attract pollinators and defenders and is protected from nectar robbers and microorganisms by secondary compounds and antimicrobial proteins. Floral and extrafloral nectar secretion can be induced by jasmonic acid, it is often adjusted to consumer identity and consumption rate and depends on invertase activity. Invertases are likely to play at least three roles: the uploading of sucrose from the phloem, carbohydrate mobilization during active secretion and the postsecretory adjustment of the sucrose:hexose ratio of nectar. However, it remains to be studied how plants produce and secrete non-carbohydrate components. More research is needed to understand how plants produce nectar, the most important mediator of their interactions with mutualistic animals. [Copyright &y& Elsevier]

Abstract: Automatic semantic activation was recently called a myth when the behavioral semantic priming effect was found to be subject to task demands. Semantic priming effects as measured by lexical decision times are typically reduced to the point of being absent when a letter search has to be performed on the prime word. It seems premature to draw any definite conclusion from this behavioral result as ERP recordings show that the same prime task leaves N400 priming effects unaffected. It is still a matter of debate whether N400 priming effects are generated chiefly by automatic or by cognitively controlled priming processes. In the present study we therefore recorded both lexical decision times and ERPs while we varied the ratio of related to unrelated prime–probe pairs (25% vs. 75% related) and thus manipulated the degree to which controlled mechanisms contribute to the semantic priming effect. Behavioral measures revealed reliable semantic priming effects only when RP was high and the influence of controlled processes hence increased. The modulation of the N400, however, provided clear-cut evidence of semantic processing at both RPs, indicating that semantic activation occurred even when RP was low and the involvement of controlled mechanisms was thus minimal. [ABSTRACT FROM AUTHOR]

Abstract: Numerous lines of research indicate that attentional processes, working memory and saccadic processes are highly interrelated. In the current study, we examine the relation between these processes with respect to their cognitive-neurophysiological and neurobiological background by means of event-related potentials (ERPs) in a sample of N =72 healthy probands characterized for the functional serotonin receptor 1 A (5-HT1A) C(−1019)G polymorphism. The results support a close interrelation between working memory, attentional and saccadic processes. Yet, these processes are differentially modulated by the 5-HT1A C(−1019)G polymorphism. The 5-HT1A C(−1019)G polymorphism primarily affects attentional processing, whereas processes related to the mental rotation of an object are independent of 5-HT1A genetic variation. It is shown that an increasing number of −1019 G alleles leads to a differential reduction of the N1 above the left and right hemisphere and hence bottom-up attentional processing. In the way increasing numbers of −1019 G alleles lead to a reduction of attentional processes, saccadic activity increases as a similar function of the number of −1019 G alleles. This increase in activity occurs parallel in time to the process of mental rotation. It is hypothesized that decreased attentional processes, dependent on different 5-HT1A C(−1019)G genotypes, may cause parietal networks to increase saccadic activity in order to perform mental rotation. [Copyright &y& Elsevier]

In spite of initial doubts about the reality of ‘talking trees’, plant resistance expression mediated by volatile compounds that come from neighboring plants is now well described. Airborne signals usually improve the resistance of the receiver, but without obvious benefits for the emitter, thus making the evolutionary explanation of this phenomenon problematic. Here, we discuss four possible non-exclusive explanations involving the role of volatiles: in direct defense, as within-plant signals, as traits that synergistically interact with other defenses, and as cues among kin. Unfortunately, there is a lack of knowledge on the fitness consequences of plant communication for both emitter and receiver. This information is crucial to understanding the ecology and evolution of plant communication via airborne cues. [Copyright &y& Elsevier]

Feeding by herbivores induces plant defences, but we still do not know all the signals that mediate this response. Here, I argue that a general principle in this mediation is ‘damaged-self recognition’, that is, the perception of motifs by the plant that indicate disintegrated plant cells. Most defence-inducing molecules are (or contain) plant-derived motifs or disintegrate plant cells and thereby release defence elicitors. By perceiving the ‘damaged self’, plants can retain evolutionary control over their interactions with herbivores rather than allowing herbivores to dominate the interaction. The concept of ‘damaged-self recognition’ provides a paradigm for plant responses to herbivory and helps the search for the currently unknown elicitors of those defence responses, which have so far only been described at the phenotypic level. [Copyright &y& Elsevier]

Abstract: The otherwise robust behavioral semantic priming effect is reduced to the point of being absent when a letter search has to be performed on the prime word. As a result the automaticity of semantic activation has been called into question. It is unclear, however, in how far automatic processes are even measurable in the letter search priming paradigm as the prime task necessitates a long prime–probe stimulus-onset asynchrony (SOA). In a modified procedure, a short SOA can be realized by delaying the prime task response until after participants have made a lexical decision on the probe. While the absence of lexical decision priming has already been demonstrated in this design it seems premature to draw any definite conclusions from this purely behavioral result since event related potential (ERP) measures have been shown to be a more sensitive index of semantic activation. Using the modified paradigm we thus recorded ERP in addition to lexical decision times. Stimuli were presented at two different SOAs (240ms vs. 840ms) and participants performed either a grammatical discrimination (Experiment 1) or a letter search (Experiment 2) on the prime. Irrespective of prime task, the modulation of the N400, the ERP correlate of semantic activation, provided clear-cut evidence of semantic processing at the short SOA. Implications for theories of semantic activation as well as the constraints of the delayed prime task procedure are discussed. [Copyright &y& Elsevier]

Plants use inducible defence mechanisms to fend off harmful organisms. Resistance that is induced in response to local attack is often expressed systemically, that is, in organs that are not yet damaged. In the search for translocated defence signals, biochemical studies follow the physical movement of putative signals, and grafting experiments use mutants that are impaired in the production or perception of these signals. Long-distance signals can directly activate defence or can prime for the stronger and faster induction of defence. Historically, research has focused on the vascular transport of signalling metabolites, but volatiles can play a crucial role as well. We compare the advantages and constraints of vascular and airborne signals for the plant, and discuss how they can act in synergy to achieve optimised resistance in distal plant parts. [Copyright &y& Elsevier]

Abstract: Some recent evidence suggests that mental rotation of characters in children aged 7 or 8 years might be lateralized to the left parietal hemisphere. An alternative statement exists, however, the finding might be completely unspecific for mental rotation but either be simply a function of task difficulty or a consequence of the use of characters as stimuli. To test these alternatives, ERPs of 24 second graders were measured twice: (a) during mental rotation with characters as stimuli and orientations of 30°, 90°, or 150° and (b) during memory scanning with characters as stimuli and set sizes of 1, 2, or 3 letters. In both cases, an amplitude modulation was found. The effect of mental rotation as a function of character orientation turned out to be lateralized to the left parietal hemisphere. The effect of memory scanning as a function of set size, however, turned out to be completely non-lateralized. Thus, children''s left hemisphere activation during mental rotation is reliable as well as specific. [Copyright &y& Elsevier]

Abstract: Motivated by models that propose material-specific cortical long-term memory representations we expected different topographies of event-related slow waves of the EEG during cued retrieval of two distinct types of information (faces and spatial positions), which are assumed to be processed and stored in topographically distinct cortical areas, i.e., in either the ventral or the dorsal visual pathway. Seventeen participants learned associations either between words and spatial positions or between words and faces. Each word was associated with either one or two positions or faces. In a cued recall test, one day later, participants saw two words and had to decide whether these were linked to each other via an associated spatial position or a face. Slow event-related potentials (ERPs) of the EEG were recorded from 61 scalp electrodes during both acquisition and recall. Response times increased monotonically with the number of faces and positions to be reactivated. Negative slow ERPs showed a comparable topography during anticipation learning and cued recall, but dissociated topographically for positions and faces. The maximum of the negativity increased when items were presented repetitively (compared to the first presentation) during learning, and also with the number of the to-be-reactivated associations during retrieval. These results are consistent with an information-processing model that assumes material-specific cortical representations of episodic memory contents, which are established as localized cortical cell assemblies during encoding, and which are being reactivated during recall. [Copyright &y& Elsevier]

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Repetition blindness (RB) was used to investigate whether illusory words emerge at a lexical-perceptual or a semantic-reconstructional level. Illusory words were evoked by the rapid serial visual presentation (RSVP) of two real words and a word fragment. The initial words share the same string of letters (“CREEP”–“SHEEP”), producing a free-floating word fragment (“SH”). This fragment is likely to be linked to a subsequently presented fragment (“IFT”) if both combine to a meaningful word (“SHIFT”). The processing level of the illusions was probed by prime words preceding the RSVP sequence which were semantically related or unrelated to the second real word or to the illusion. Behavioural and electrophysiological correlates of the semantic priming effect were recorded in 14 subjects. Real words related to the prime were perceived more frequently, and evoked widespread N400-like effect in the event-related brain potentials (ERPs). An ERP effect of the same polarity was obtained for illusory words, however, its latency was delayed and the topographical distribution was restricted to left posterior electrode positions. These differences suggest that priming might affect real and illusory words at different levels of word processing: access to real words is facilitated at a semantic level, whereas lexical activation apparently accompanies the generation of illusory words. [Copyright &y& Elsevier]

There has been rapid progress in detecting the genetic or allocation costs of induced resistance. In addition to these ‘internal’ costs, ecological costs may result from external mechanisms, that is, from the detrimental effects of resistance on the plant''s interactions with its environment. All evolutionarily relevant costs affect a plant''s ability to perform under natural conditions. The conceptual separation of different forms of resistance costs simplifies the study of mechanisms by which these costs arise. Yet, integrative measures of fitness must be applied under natural conditions so that researchers can fully understand the costs and benefits of induced resistance. [ABSTRACT FROM AUTHOR]

Fitness costs can explain the evolution and maintenance of induced resistance in plants. However, the methods currently used to gather evidence for such costs do not allow decreases in fitness to be cleanly attributed to individual traits responsible for induced resistance, because the studies are plagued by multiple confounding responses. Reproductive performance provides an overview of physiological performance and is thus a useful currency to understand the function of induced responses. Integrated molecular, physiological and ecological studies are needed to identify the mechanisms responsible for the decrease in fitness and to evaluate fully the usefulness of the cost paradigm. [ABSTRACT FROM AUTHOR]

A recent study reports partner manipulation for an interaction that was considered a reward-for-defence mutualism. Secretions of lycaenid caterpillars altered ant locomotion and aggressiveness, likely by manipulating dopaminergic signalling. This study opens the question whether such manipulation is common and whether manipulation necessarily characterises an interaction as parasitism. [ABSTRACT FROM AUTHOR]

Wounded nightshade leaves secrete a sugary liquid that, like extrafloral nectar (EFN), attracts ants as defence against herbivores. The secretion of these droplets requires no detectable nectary tissue, showing how little it takes to produce a functioning nectary. Easy de novo formation of extrafloral nectaries explains their ‘scattered’ phylogenetic distribution. [ABSTRACT FROM AUTHOR]

Highlights • Previous research revealed inconclusive results with respect to (sex differences in) mental rotation in infants. • We used dynamic 3D stimuli and sufficient statistical power while measuring 5 and 9 month old infants' looking times. • 5 month old infants (N = 208) provided evidence for mental rotation in the absence of sex differences. • 9 month old infants (N = 168) provided no evidence for mental rotation, no sex differences, no effect of motor development. • Thus, evidence for sex differences in mental rotation in infancy was absent although statistical power was sufficient. Abstract In adults, the paper-and-pencil Mental Rotation Test (MRT) consistently produces large sex differences favouring men. In contrast, sex effects in response times in the mental rotation task are small or absent. In recent years, a number of studies using different stimuli and experimental approaches investigated sex differences in mental rotation in infants with inconsistent results. The goal of the present study was to examine on the basis of a sufficient statistical power (a) whether infants aged 5–6 (N = 208) or 9–10 months (N = 168) are able to use mental rotation in a habituation task with complex and dynamic 3D cube figures rotated in depth; (b) whether there were sex differences present, (c) whether looking times at 5–6 months can predict looking times at 9–10 months, and finally, (d) whether 9-month-olds' looking times during mental rotation depend upon their crawling ability. Our data suggest that the habituation paradigm is suited to reveal mental rotation in 5- to 6-month-old infants (although the effects are small) but not in older ones. Moreover, we obtained no evidence for sex differences, we found no stability of looking times across infancy, and obtained no evidence suggesting an effect of crawling experience on mental rotation ability. More studies based on sufficiently large sample sizes are needed to evaluate mental rotation and possible sex differences in infancy. [ABSTRACT FROM AUTHOR]

Defense priming conditions diverse plant species for the superinduction of defense, often resulting in enhanced pest and disease resistance and abiotic stress tolerance. Here, we propose a guideline that might assist the plant research community in a consistent assessment of defense priming in plants. [ABSTRACT FROM AUTHOR]

Abstract: In psychometric mental-rotation tasks, adult male participants usually outperform females. A large body of evidence suggests that this effect is reliable, quite stable over lifespan and one of the largest cognitive gender differences. However, there are controversial findings regarding the age in which the male advantage emerges. The present study aimed at contributing to a systematic developmental research of mental rotation by examining two grades and three stimulus types in order to determine how these variables influence the gender difference. Second and fourth graders (n =432) were tested with a paper–pencil mental-rotation task in three stimulus conditions (animal pictures, letters, cube figures). Whereas fourth graders showed a small, but significant, stimulus-independent gender difference favoring males, there was no effect of gender on the mental-rotation performance of second graders. Fourth-grade boys performed better than second-grade boys in all stimulus conditions. Fourth-grade girls, in contrast, outperformed second-grade girls in the animal pictures condition and the letters condition, but not in the cube-figures condition. Results are discussed with regard to implications for causal mechanisms underlying the gender difference in mental rotation. [Copyright &y& Elsevier]

Abstract: The influence of gender beliefs on cognitive task performance has been demonstrated repeatedly for adults. For children, there is evidence that gender beliefs can substantially impede or boost math performance — a task where gender differences in favour of boys declined over past decades. Therefore, we examined this phenomenon using the Mental Rotations Test (MRT), a task where gender differences still occur reliably favouring males — for adults as well as for children. A sample of 252 fourth graders, whose beliefs about spatial ability were manipulated experimentally (instructions given: boys are better, girls are better or independent of gender) had to complete the MRT. In contrast to adult''s literature, children''s performance did not decrease or increase as a function of instruction: boys always outperformed girls; girls not even outperformed their same-sex counterparts given the “girls better” instruction. The transfer of the conceptual approach failed — possible reasons are discussed. [Copyright &y& Elsevier]

• Girls are better able to delay gratification than boys. • Boys with higher prenatal testosterone levels are less able to delay gratification. • Boys with higher prenatal testosterone levels show more attentions problems/overactive behavior. • Boys with more attention problems/overactive behavior are less able to delay gratification. Sex differences in self-control become apparent during preschool years. Girls are better able to delay their gratification and show less attention problems and overactive behavior than boys. In this context, organizational effects of gonadal steroids affecting the neural circuitry underlying self-control could be responsible for these early sex differences. In the present study testosterone levels measured in amniotic fluid (via ultra performance liquid chromatography and tandem mass spectrometry) were used to examine the role of organizational sex hormones on self-control. One hundred and twenty-two 40-month-old children participated in a delay of gratification task (DoG task) and their parents reported on their attention problems and overactive behavior. Girls waited significantly longer for their preferred reward than boys, and significantly more girls than boys waited the maximum period of time, providing evidence for sex differences in delay of gratification. Boys that were rated as suffering from more attention problems and overactive behavior waited significantly shorter in the DoG task. Amniotic testosterone measures were reliable in boys only. Most importantly, boys who waited shorter in the DoG task and boys who were reported to suffer from more attention problems and overactive behavior had higher prenatal testosterone levels. These findings extend our knowledge concerning organizational effects of testosterone on the brain circuitry underlying self-control in boys, and are of relevance for understanding how sex differences in behavioral disorders are connected with a lack of self-control. [ABSTRACT FROM AUTHOR]

Abstract: We assessed conceptual priming for environmental sounds in two tasks using pairs of a visually presented word (prime) and an environmental sound (probe). In the physical task, participants indicated to which ear the sound was presented. In the semantic task, participants judged whether a word labeled a sound correctly. The physical always preceded the semantic task to exclude semantic carry-over effects. In both tasks prime word color indicated whether a response was required (Go/NoGo-trials). An N400-effect for unrelated vs. related sounds was observed in all four conditions resulting from the combination of both tasks with response requirement. However, the N400-effect was reduced in the physical task and in NoGo-trials. Hence, meaning of environmental sounds may be processed obligatorily. Both automatic and controlled processes mediate the analysis of sound meaning. [Copyright &y& Elsevier]