Ms Of Exposure Research Articles

Trait impressions from voices are formed rapidly within 400 ms of exposure.

When seeing a face or hearing a voice, perceivers readily form first impressions of a person's characteristics-are they trustworthy, do they seem aggressive? One of the key claims about trait impressions from faces and voices alike is that these impressions are formed rapidly. For faces, studies have systematically mapped this rapid time course of trait impressions, finding that they are well formed and stable after approximately 100 ms of exposure. For voices, however, no systematic investigation of the time course of trait perception exists. In the current study, listeners provided trait judgments (attractiveness, dominance, trustworthiness) based on recordings of 100 voices that lasted either 50, 100, 200, 400, or 800 ms. Based on measures of intra- and interrater agreement as well as correlations of mean ratings for different exposure conditions, we find that trait perception from voices is indeed rapid. Unlike faces, however, trait impressions from voices require longer exposure to develop and stabilize although they are still formed by 400 ms. Furthermore, differences in the time course of trait perception from voices emerge across traits and voice gender: The formation of impressions of attractiveness and dominance required less exposure when based on male voices, whereas impressions of trustworthiness evolved over a more gradual time course for male and female voices alike. These findings not only provide the first estimate of the time course of the formation of voice trait impressions, but they also have implications for voice perception models where voices are regarded as "auditory faces." (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Supplemental Material for Trait Impressions From Voices Are Formed Rapidly Within 400 ms of Exposure

Supplemental Material for Trait Impressions From Voices Are Formed Rapidly Within 400 ms of Exposure

Drawings reveal accurate visual information in memory after just 100 ms of exposure

Drawings reveal accurate visual information in memory after just 100 ms of exposure

Estimating Response Time in Spatial Frequency Band Experiments involving Visual Perception

The present study aimed to determine the optimum response time (RT) needed to identify images of everyday objects when filtered using different spatial frequency bands. Subjects were randomly presented with different images of familiar objects that were both serialized and progressive in their spatial frequencies. The time needed to recognize them was then measured. The results showed that the optimum RT for identifying an image filtered in different spatial frequency bands was approximately 2000 ms of exposure. Specifically, stimuli presented using spatial frequency bands with Gaussian filters of variance V26-V32, which were familiar and of medium size to the viewer, were recognized in a mean time of 2126 ms.

Is believing seeing? The role of emotion-related beliefs in selective attention to affective cues

Attentional disengagement from negative affective information and engagement toward positive affective information appears to reflect an avoidant coping mechanism, one that may be associated with the belief that negative emotions are dangerous or undesirable (BNED). To test this hypothesis, we conducted two studies using a dot-probe task measuring attentional preference among college undergraduates. In the first study, BNED was associated with an attentional preference for positive facial cues over negative facial cues, evident after 1000 ms of exposure. In the second study, we included three exposure-time conditions; BNED appeared to be associated with an early disengagement from negative facial cues between 500 and 750 ms post-exposure and a subsequent orientation toward positive facial cues between 750 and 1000 ms post-exposure. We discuss these results in relation to avoidant coping and the relationship between anxiety and attention to affective cues.

Time Dependence of Demagnetization and Flux Losses Occurring in Sintered Nd-Fe-B Permanent Magnets

It is a common impression that the measured B(H) curves of permanent-magnet materials indicate the temperature and the operating point at which flux losses start to occur. As long as the operating point stays above the knee of the B(H) curve, no losses will be expected. The demagnetization process is, however, a time-dependent process and losses occurring immediately are followed by a thermal aftereffect. Here, we report our study of the time dependence of flux losses in commercial permanent Nd-Fe-B magnets. We present flux losses as a function of temperature for different exposure times. We then compare the measured B(H) curves of the Nd-Fe-B material to the results of loss measurements. We found that B(H) curves will not always indicate the overall losses well. The measured B(H) curve represents the demagnetization state of the tested magnet more or less after only 10 ms of exposure to the elevated temperature. When the operating point of the magnet is approaching the B(H) curve knee, the time-dependent losses will become significant. To control the time-dependent losses in sintered Nd-Fe-B magnets, the operating point needs to be sufficiently far away from the knee of the B(H) curve.

Predicting political elections from rapid and unreflective face judgments

Here we show that rapid judgments of competence based solely on the facial appearance of candidates predicted the outcomes of gubernatorial elections, the most important elections in the United States next to the presidential elections. In all experiments, participants were presented with the faces of the winner and the runner-up and asked to decide who is more competent. To ensure that competence judgments were based solely on facial appearance and not on prior person knowledge, judgments for races in which the participant recognized any of the faces were excluded from all analyses. Predictions were as accurate after a 100-ms exposure to the faces of the winner and the runner-up as exposure after 250 ms and unlimited time exposure (Experiment 1). Asking participants to deliberate and make a good judgment dramatically increased the response times and reduced the predictive accuracy of judgments relative to both judgments made after 250 ms of exposure to the faces and judgments made within a response deadline of 2 s (Experiment 2). Finally, competence judgments collected before the elections in 2006 predicted 68.6% of the gubernatorial races and 72.4% of the Senate races (Experiment 3). These effects were independent of the incumbency status of the candidates. The findings suggest that rapid, unreflective judgments of competence from faces can affect voting decisions.

The role of spatial location in auditory search

The majority of research findings to date indicate that spatial cues play a minor role in enhancing listeners’ ability to parse and detect a sound of interest when it is presented in a complex auditory scene comprising multiple simultaneous sounds. Frequency and temporal differences between sound streams provide more reliable cues for scene analysis as well as for directing attention to relevant auditory ‘objects’ in complex displays. The present study used naturalistic sounds with varying spectro-temporal profiles to examine whether spatial separation of sound sources can enhance target detection in an auditory search paradigm. The arrays of sounds were presented in virtual auditory space over headphones. The results of Experiment 1 suggest that target detection is enhanced when sound sources are spatially separated relative to when they are presented at the same location. Experiment 2 demonstrated that this effect is most prominent within the first 250 ms of exposure to the array of sounds. These findings suggest that spatial cues may be effective for enhancing early processes such as stream segregation, rather than simply directing attention to objects that have already been segmented.

The Rates of Type I X‐Ray Bursts from Transients Observed withRXTE: Evidence for Black Hole Event Horizons

We measure the rates of type I X-ray bursts from a likely flux-limited sample of 37 nonpulsing Galactic transients observed with RXTE during 1996-2004. These sources are well categorized in the literature as either neutron star systems or black hole candidates. Our goals are to test the burst model for neutron stars and to investigate whether black holes have event horizons. Target selection is one of several differences between the present study and the investigation of the event horizon question by Tournear and coworkers. Burst rates are measured as a function of bolometric luminosity, and the results are compared with augmented versions of the burst model developed by Narayan & Heyl. For a given mass, we consider a range in both the radius and the temperature at the boundary below the accretion layer. We find 135 spectrally confirmed type I bursts in 3.7 Ms of PCA exposures for the neutron star group (13 sources), and the burst rate function is generally consistent with the model predictions. However, for the black hole groups (18 sources), there are no confirmed type I bursts in 6.5 Ms of exposure, and the upper limits in the burst function are inconsistent with the model predictions for heavy compact objects with a solid surface. The consistency probability is ~2 × 10-7 for dynamical black hole binaries, falling to 3 × 10-13 with the added exposures of black hole candidates. Furthermore, there are systematic spectral differences between the neutron star and black hole groups, supporting the presumption that physical differences underly the classifications in our sample. These results provide indirect evidence that black holes do have event horizons.

Resolving the source populations that contribute to the X‐ray background: The 2 Ms Chandra Deep Field‐North Survey

AbstractWith ≈ 2 Ms of exposure, the Chandra Deep Field‐North (CDF‐N) survey provides the deepest view of the Universe in the 0.5–8.0 keV band. Five hundred and three (503) X‐ray sources are detected down to on‐axis 0.5–2.0 keV and 2–8 keV flux limits of ≈ 1.5 × 10–17 erg cm–2 s–1 and ≈ 1.0 × 10–16 erg cm–2 s–1, respectively. These flux limits correspond to L0.5–8.0 keV≈ 3 × 1041 erg s–1 at z = 1 and L0.5–8.0 keV≈ 2 × 1043 erg s–1 at z = 6; thus this survey is sensitive enough to detect starburst galaxies out to moderate redshift and Seyfert galaxies out to high redshift.We present the X‐ray observations, describe the broad diversity of X‐ray selected sources, and review the prospects for deeper exposures.

Study of the X-Ray Background Spectrum and Its Large-Scale Fluctuation with ASCA

Abstract We studied the energy spectrum and the large-scale fluctuation of the X-ray background with the ASCA GIS instrument based on the ASCA Medium Sensitivity Survey and Large Sky Survey observations. A total of 91 fields with Galactic latitude $|b| \gt 10^\circ$ were selected with a sky coverage of 50 deg$^2$ and 4.2 Ms of exposure. For each field, non-X-ray events were carefully subtracted and sources brighter than $\sim 2\times 10^{-13} \,\mathrm{erg} \,\mathrm{cm}^{-2} \,\mathrm{s}^{-1}$ (2–10 keV) were eliminated. Spectral fits with a single power-law model for the individual 0.7–10 keV spectra showed a significant excess below $\sim 2 \,\mathrm{keV}$, which could be expressed by an additional thermal model with $kT\simeq 0.4 \,\mathrm{keV}$ or a steep power-law model with a photon index of $\Gamma^\mathrm{soft}\simeq 6$. The 0.5–2 keV intensities of the soft thermal component varied significantly from field to field by $1\,\sigma= 52^{+4}_{-5}\%$, and showed a maximum toward the Galactic Center. This component is considered to be entirely Galactic. As for the hard power-law component, an average photon index of 91 fields was obtained to be $\Gamma^\mathrm{hard} = 1.412\pm 0.007\pm 0.025$ and the average 2–10 keV intensity was calculated as $F_\mathrm{X}^\mathrm{hard} = (6.38\pm 0.04\pm 0.64)\times 10^{-8} \,\mathrm{erg} \,\mathrm{cm}^{-2} \,\mathrm{s}^{-1} \,\mathrm{sr}^{-1}$ ($1\,\sigma$ statistical and systematic errors). The Galactic component is marginally detected in the hard band. The 2–10 keV intensities show a $1\,\sigma$ deviation of $6.49^{+0.56}_{-0.61}\%$, while deviation due to the reproducibility of the particle background is 3.2%. The observed deviation can be explained by the Poisson noise of the source count in the f.o.v. ($\sim 0.5 \,\mathrm{deg}^2$), even assuming a single $\log{N} \hbox{--} \log{S}$ relation on the whole sky. Based on the observed fluctuation and the absolute intensity, an acceptable region of the $\log{N} \hbox{--} \log{S}$ relation was derived, showing a consistent feature with the recent Chandra and XMM-Newton results. The fluctuation of the spectral index was also examined; it implied a large amount of hard sources and a substantial variation in the intrinsic source spectra ($\Gamma_\mathrm{S}\simeq 1.1\pm 1.0$).

Hypochlorous acid-promoted loss of metabolic energy in Escherichia coli.

Oxidation of Escherichia coli by hypochlorous acid (HOCl) or chloramine (NH2Cl) gives rise to massive hydrolysis of cytosolic nucleotide phosphoanhydride bonds, although no immediate change occurs in either the nucleotide pool size or the concentrations of extracellular end products of AMP catabolism. Titrimetric curves of the extent of hydrolysis coincide with curves for loss of cell viability, e.g., reduction in the adenylate energy charge from 0.8 to 0.1-0.2 accompanies loss of 99% of the bacterial CFU. The oxidative damage caused by HOCl is irreversible within 100 ms of exposure of the organism, although nucleotide phosphate bond hydrolysis requires several minutes to reach completion. Neither HOCl nor NH2Cl reacts directly with nucleotides to hydrolyze phosphoanhydride bonds. Loss of viability is also accompanied by inhibition of induction of beta-galactosidase. The proton motive force, determined from the distribution of 14C-radiolabeled lipophilic ions, declines with incremental addition of HOCl after loss of respiratory function; severalfold more oxidant is required for the dissipation of the proton motive force than for loss of viability. These observations establish a causal link between loss of metabolic energy and cellular death and indicate that the mechanisms of oxidant-induced nucleotide phosphate bond hydrolysis are indirect and that they probably involve damage to the energy-transducing and transport proteins located in the bacterial plasma membrane.