Mere Presence (mere + presence)

Distribution by Scientific Domains


Selected Abstracts


Mere presence of distractors: Another determining factor for the attentional blink1

JAPANESE PSYCHOLOGICAL RESEARCH, Issue 3 2003
Jun-Ichiro Kawahara
Abstract: When two visual targets are presented in rapid succession, perception of the second target is deteriorated if the temporal lag between the two targets is short (0,300 ms). This ,attentional blink' (AB) phenomenon has been believed to occur only when the second target is followed by a backward mask or when there is a task switching between two targets. The present study revealed another determining factor for the occurrence of the AB, the presence or absence of a distractor stream. Five experiments examined the effect of possible confounding factors in the extant literature and suggested that the mere presence of a distractor stream affects the processing of targets even when the observers tried to ignore them, resulting in a processing delay. This effect is discussed in a model of AB deficit in terms of decay of the second target's representation. [source]


Rumination in posttraumatic stress disorder

DEPRESSION AND ANXIETY, Issue 5 2007
Tanja Michael Ph.D.
Abstract Recent studies have shown that rumination is a powerful predictor of persistent posttraumatic stress disorder (PTSD). However, to date, the mechanisms by which rumination maintains PTSD symptoms are little understood. Two studies of assault survivors, a cross-sectional (N = 81) and a 6-month prospective longitudinal study (N = 73), examined several facets of ruminative thinking to establish which aspects of rumination provide the link to PTSD. The current investigation showed that rumination is not only used as a strategy to cope with intrusive memories but it also triggers such memories. Certain characteristics of rumination, such as compulsion to continue ruminating, occurrence of unproductive thoughts, and "why" and "what if" type questions, as well as negative emotions before and after rumination, were significantly associated with PTSD, concurrently and prospectively. These characteristics explained significantly more variance in PTSD severity than the mere presence of rumination, thereby indicating that not all ways of ruminative thinking are equally maladaptive. Depression and Anxiety 24:307,317, 2007. © 2006 Wiley-Liss, Inc. [source]


Enemy Recognition of Reed Warblers (Acrocephalus scirpaceus): Threats and Reproductive Value Act Independently in Nest Defence Modulation

ETHOLOGY, Issue 6 2010
Daniela Campobello
Organisms should respond more aggressively towards species perceived as a danger to their offspring, but intensity of defence may be gauged by the value of current offspring weighed against the value of future reproductive opportunities. We tested whether defensive responses of nesting reed warblers (Acrocephalus scirpaceus) are the result of an interaction effect between the type of stimulus confronted and the value of the warbler's nesting attempt. We quantified the ability of reed warblers to discriminate among brood parasites, nestling predators and non-threatening species at different stages of the breeding cycle. We also determined whether variables that influence the value of offspring, such as time of season, size and age of clutch or brood, and time of day and number of visits to the nest, explain variation in the intensity of defence recorded during the egg and nestling stages. Responses to the three stimuli differed significantly, as reed warblers consistently directed their mobbing calls and attacks towards parasites, whereas they were less conspicuous when confronted with models of predators. Reed warblers modulated their responses towards each stimulus in accordance with the threat each posed at a specific nesting stage, whereas they were not affected by other variables relative to their reproductive potential. The churr call, however, was uttered independently of the stimulus, as it was triggered by the mere presence of nestlings in the nest. [source]


Employee buyouts and employee involvement: a case study investigation of employee attitudes

INDUSTRIAL RELATIONS JOURNAL, Issue 5 2000
Lisa Trewhitt
This article investigates the association between employee share ownership (ESO) and employee involvement (EI) in an employee-owned firm.Based on data from the firm's employers and employees, the article concludes that the mere presence of share ownership is no guarantee on increased involvement for employees, highlighting instead the significance of other variables. [source]


Mere presence of distractors: Another determining factor for the attentional blink1

JAPANESE PSYCHOLOGICAL RESEARCH, Issue 3 2003
Jun-Ichiro Kawahara
Abstract: When two visual targets are presented in rapid succession, perception of the second target is deteriorated if the temporal lag between the two targets is short (0,300 ms). This ,attentional blink' (AB) phenomenon has been believed to occur only when the second target is followed by a backward mask or when there is a task switching between two targets. The present study revealed another determining factor for the occurrence of the AB, the presence or absence of a distractor stream. Five experiments examined the effect of possible confounding factors in the extant literature and suggested that the mere presence of a distractor stream affects the processing of targets even when the observers tried to ignore them, resulting in a processing delay. This effect is discussed in a model of AB deficit in terms of decay of the second target's representation. [source]


The impact of predation risk from small mustelids on prey populations

MAMMAL REVIEW, Issue 3-4 2000
Kai Norrdahl
ABSTRACT Small mustelids are ,snake-like' mammals adapted to hunt small rodents, which are their principal prey, in tunnels leaving practically no refuge for the prey. Prey rodents have adaptive behaviours to situations where the predation risk from mustelids is high, including reduced activity and escape by climbing. Small mustelids may affect prey population dynamics directly through killing (increased mortality) and/or indirectly through behavioural changes in prey as a response to the presence of mustelids (predation risk). The Predator-Induced Breeding Suppression hypothesis (PIBS) states that a trade-off between survival and reproduction should lead to delayed breeding under temporarily high predation risk, so that the mere presence of predators may reduce reproductive output. Current results suggest that small mustelids mainly affect prey population growth rate directly through killing. In many cyclic rodent populations, small mustelid predation is a major mortality factor, and experimental evidence supports the hypothesis that these predators drive prolonged summer declines in prey. In contrast, the evidence for PIBS is controversial. Experimental evidence shows that the indirect effects of small mustelids on prey populations are negligible during the best breeding season. However, in other seasons, the presence of predators may indirectly affect prey populations, although this has not been studied experimentally. Prey rodents may decrease mobility as a response to high predation risk by small mustelids, and this reduction in mobility decreases feeding. Reduced feeding affects the energy reserves of voles, and may delay maturation or lower the size of the first litter. [source]


Using ColE1-derived RNA I for suppression of a bacterially encoded gene: implication for a novel plasmid addiction system

BIOTECHNOLOGY JOURNAL, Issue 6 2006
Irene Pfaffenzeller
Abstract The use of plasmid DNA for gene therapeutical purposes is a novel technology with advantages and drawbacks. One of the required improvements is to avoid antibiotic resistance genes or other additional sequences for selection within the plasmid. Here, we describe an alternative approach to equip a ColE1 plasmid with a regulatory function within the cell, which could be used for selection of plasmid carrying cells. No additional sequences are required, since the mechanism is based on RNA/RNA antisense interaction involving the naturally occurring RNA I derived from the plasmid's origin of replication. The plasmid replicational regulatory network was linked to the transcriptional regulatory network of an engineered target gene, present on the bacterial chromosome. Thus, gene suppression of a reporter could be achieved by mere presence of the ColE1-type plasmid pBR322. Proof of this concept was shown in shaker-flask experiments and fed-batch fermentation processes. The strategy of regulating gene expression by plasmid replication implicates a novel strategy for plasmid selection, as the gene to be suppressed could be toxic or growth hampering, providing advantage to plasmid carrying host cells. [source]