423 research outputs found
Serum antibody response to Chlamydia trachomatis TroA and HtrA in women with tubal factor infertility
Persistent genital chlamydial infection may lead to tubal factor infertility (TFI). Chlamydia trachomatis TroA and HtrA are proteins expressed during persistent chlamydial infection in vitro. We studied serum IgG antibody response against these proteins by EIA in women with TFI and in subfertile women without tubal pathology. Altogether, 22 of 258 subfertile women (8.5%) had TFI which was unilateral in 17 cases and bilateral in 5 cases. Overall, 55 (21.3%) of the 258 women had TroA and 39 (15.1%) had HtrA antibodies. Seropositivity to TroA and HtrA was more common among women with TFI than women with other causes for subfertility (45.5 vs. 19.1%, p = 0.004 for TroA; 36.4 vs. 13.1%, p = 0.004 for HtrA). Mean absorbance values and the prevalence of TroA and HtrA antibodies increased with increasing severity of TFI. On the basis of our results, TroA and HtrA serology has the potential to be further developed to a specific biomarker for C. trachomatis-related TFI.Peer reviewe
Rapid detection of snakes modulates spatial orienting in infancy
Recent evidence for an evolved fear module in the brain comes from studies showing that adults, children and infants detect evolutionarily threatening stimuli such as snakes faster than non-threatening ones. A decisive argument for a threat detection system efficient early in life would come from data showing, in young infants, a functional threat-detection mechanism in terms of “what” and “where” visual pathways. The present study used a variant of Posner’s cuing paradigm, adapted to 7–11-month-olds. On each trial, a threat-irrelevant or a threat-relevant cue was presented (a flower or a snake, i.e., “what”). We measured how fast infants detected these cues and the extent to which they further influenced the spatial allocation of attention (“where”). In line with previous findings, we observed that infants oriented faster towards snake than flower cues. Importantly, a facilitation effect was found at the cued location for flowers but not for snakes, suggesting that these latter cues elicit a broadening of attention and arguing in favour of sophisticated “what–where” connections. These results strongly support the claim that humans have an early propensity to detect evolutionarily threat-relevant stimuli
A survey on worries of pregnant women - testing the German version of the Cambridge Worry Scale
Background: Pregnancy is a transition period in a woman's life characterized by increased worries and anxiety. The Cambridge Worry Scale (CWS) was developed to assess the content and extent of maternal worries in pregnancy. It has been increasingly used in studies over recent years. However, a German version has not yet been developed and validated. The aim of this study was (1) to assess the extent and content of worries in pregnancy on a sample of women in Germany using a translated and adapted version of the Cambridge Worry Scale, and (2) to evaluate the psychometric properties of the German version. Methods: We conducted a cross-sectional study and enrolled 344 pregnant women in the federal state of Baden-Wurttemberg, Germany. Women filled out structured questionnaires that contained the CWS, the Spielberger-State-Trait-Anxiety Inventory (STAI), as well as questions on their obstetric history. Antenatal records were also analyzed. Results: The CWS was well understood and easy to fill in. The major worries referred to the process of giving birth (CWS mean value 2.26) and the possibility that something might be wrong with the baby (1.99), followed by coping with the new baby (1.57), going to hospital (1.29) and the possibility of going into labour too early (1.28). The internal consistency of the scale (0.80) was satisfactory, and we found a four-factor structure, similar to previous studies. Tests of convergent validity showed that the German CWS represents a different construct compared with state and trait anxiety but has the desired overlap. Conclusions: The German CWS has satisfactory psychometric properties. It represents a valuable tool for use in scientific studies and is likely to be useful also to clinicians
Polarization due to rotational distortion in the bright star Regulus
This is the full published article (retrieved from the 6 months post-publication posting on arXiv) including the Methods and Supplementary Information sections: 33 pages, 10 figures, 8 tablesPolarization in stars was first predicted by Chandrasekhar [1] who calculated a substantial linear polarization at the stellar limb for a pure electron-scattering atmosphere. This polarization will average to zero when integrated over a spherical star but could be detected if the symmetry is broken, for example by the eclipse of a binary companion. Nearly 50 years ago, Harrington and Collins [2] modeled another way of breaking the symmetry and producing net polarization - the distortion of a rapidly rotating hot star. Here we report the first detection of this effect. Observations of the linear polarization of Regulus, with two different high-precision polarimeters, range from +42 parts-per-million (ppm) at a wavelength of 741 nm to -22 ppm at 395 nm. The reversal from red to blue is a distinctive feature of rotation-induced polarization. Using a new set of models for the polarization of rapidly rotating stars we find that Regulus is rotating at 96.5(+0.6/-0.8)% of its critical angular velocity for breakup, and has an inclination greater than 76.5 degrees. The rotation axis of the star is at a position angle of 79.5+/-0.7 degrees. The conclusions are independent of, but in good agreement with, the results of previously published interferometric observations of Regulus [3]. The accurate measurement of rotation in early-type stars is important for understanding their stellar environments [4], and course of their evolution [5].Peer reviewedFinal Accepted Versio
Corporate governance performance ratings with machine learning
We use machine learning with a cross-sectional research design to predict governance controversies and to develop a measure of the governance component of the environmental, social, governance (ESG) metrics. Based on comprehensive governance data from 2,517 companies over a period of 10 years and investigating nine machine-learning algorithms, we find that governance controversies can be predicted with high predictive performance. Our proposed governance rating methodology has two unique advantages compared with traditional ESG ratings: it rates companies' compliance with governance responsibilities and it has predictive validity. Our study demonstrates a solution to what is likely the greatest challenge for the finance industry today: how to assess a company's sustainability with validity and accuracy. Prior to this study, the ESG rating industry and the literature have not provided evidence that widely adopted governance ratings are valid. This study describes the only methodology for developing governance performance ratings based on companies' compliance with governance responsibilities and for which there is evidence of predictive validity
Attentional bias for threat: Evidence for delayed disengagement from emotional faces
The present paper reports three new experiments suggesting that the valence of a face cue can influence attentional effects in a cueing paradigm. Moreover, heightened trait anxiety resulted in increased attentional dwell-time on emotional facial stimuli, relative to neutral faces. Experiment 1 presented a cueing task, in which the cue was either an "angry", "happy", or "neutral" facial expression. Targets could appear either in the same location as the face (valid trials) or in a different location to the face (invalid trials). Participants did not show significant variations across the different cue types (angry, happy, neutral) in responding to a target on valid trials. However, the valence of the face did affect response times on invalid trials. Specifically, participants took longer to respond to a target when the face cue was "angry" or "happy" relative to neutral. In Experiment 2, the cue-target stimulus onset asynchrony (SOA) was increased and an overall inhibition of return (IOR) effect was found (i.e., slower responses on valid trials). However, the "angry" face cue eliminated the IOR effect for both high and low trait anxious groups. In Experiment 3, threat-related and jumbled facial stimuli reduced the magnitude of IOR for high, but not for low, trait-anxious participants. These results suggest that: (i) attentional bias in anxiety may reflect a difficulty in disengaging from threat-related and emotional stimuli, and (ii) threat-related and ambiguous cues can influence the magnitude of the IOR effect
Accessible and reliable neurometric testing in humans using a smartphone platform
Tests of human brain circuit function typically require fixed equipment in lab environments. We have developed a smartphone-based platform for neurometric testing. This platform, which uses AI models like computer vision, is optimized for at-home use and produces reproducible, robust results on a battery of tests, including eyeblink conditioning, prepulse inhibition of acoustic startle response, and startle habituation. This approach provides a scalable, universal resource for quantitative assays of central nervous system function.</p
Negative emotional stimuli reduce contextual cueing but not response times in inefficient search
In visual search, previous work has shown that negative stimuli narrow the focus of attention and speed reaction times (RTs). This paper investigates these two effects by first asking whether negative emotional stimuli narrow the focus of attention to reduce the learning of a display context in a contextual cueing task and, second, whether exposure to negative stimuli also reduces RTs in inefficient search tasks. In Experiment 1, participants viewed either negative or neutral images (faces or scenes) prior to a contextual cueing task. In a typical contextual cueing experiment, RTs are reduced if displays are repeated across the experiment compared with novel displays that are not repeated. The results showed that a smaller contextual cueing effect was obtained after participants viewed negative stimuli than when they viewed neutral stimuli. However, in contrast to previous work, overall search RTs were not faster after viewing negative stimuli (Experiments 2 to 4). The findings are discussed in terms of the impact of emotional content on visual processing and the ability to use scene context to help facilitate search
Threat captures attention, but not automatically: Top-down goals modulate attentional orienting to threat distractors
The rapid orienting of attention to potential threats has been proposed to proceed outside of top-down control. However, paradigms that have been used to investigate this have struggled to separate the rapid orienting of attention (i.e. capture) from the later disengagement of focal attention that may be subject to top-down control. Consequently, it remains unclear whether and to what extent orienting to threat is contingent on top-down goals. The current study manipulated the goal-relevance of threat distractors (spiders), whilst a strict top-down attentional set was encouraged by presenting the saliently colored target and the threat distracter simultaneously for a limited time. The goal-relevance of threatening distractors was manipulated by including a spider amongst the possible target stimuli (Experiment 1: spider/cat targets) or excluding it (Experiment 2: bird/fish targets). Orienting and disengagement were disentangled by cueing attention away from or towards the threat prior to its onset. The results indicated that the threatening spider distractors elicited rapid orienting of attention when spiders were potentially goal-relevant (Experiment 1) but did so much less when they were irrelevant to the task goal (Experiment 2). Delayed disengagement from the threat distractors was even more strongly contingent on the task goal and occurred only when a spider was a possible target. These results highlight the role of top-down goals in attentional orienting to and disengagement from threat. © 2016 The Psychonomic Society, Inc
- …