32 research outputs found

    Grouping by feature of cross-modal flankers in temporal ventriloquism

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    Signals in one sensory modality can influence perception of another, for example the bias of visual timing by audition: temporal ventriloquism. Strong accounts of temporal ventriloquism hold that the sensory representation of visual signal timing changes to that of the nearby sound. Alternatively, underlying sensory representations do not change. Rather, perceptual grouping processes based on spatial, temporal, and featural information produce best-estimates of global event properties. In support of this interpretation, when feature-based perceptual grouping conflicts with temporal information-based in scenarios that reveal temporal ventriloquism, the effect is abolished. However, previous demonstrations of this disruption used long-range visual apparent-motion stimuli. We investigated whether similar manipulations of feature grouping could also disrupt the classical temporal ventriloquism demonstration, which occurs over a short temporal range. We estimated the precision of participants’ reports of which of two visual bars occurred first. The bars were accompanied by different cross-modal signals that onset synchronously or asynchronously with each bar. Participants’ performance improved with asynchronous presentation relative to synchronous - temporal ventriloquism - however, unlike the long-range apparent motion paradigm, this was unaffected by different combinations of cross-modal feature, suggesting that featural similarity of cross-modal signals may not modulate cross-modal temporal influences in short time scales

    Warm deep-drawing and post drawing analysis of two Al-Mg-Si alloys

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    The increasing use of aluminium alloys in light weight structural applications is restricted mainly due to their lower room temperature formability compared to steels. Forming at higher temperature is seen as a promising solution to this problem. In the present investigation two Al-Mg-Si alloys (EN AW-6016 and EN AW-6061) were deep-drawn at room temperature and 250 C and their behaviour during drawing were compared. The effect of ram speed, drawing ratio, holding time, and temper was also investigated. Among the parameters investigated temperature was found to have the most significant effect on the force-displacement response. Because anisotropy has been an important concern during the deep-drawing process, this parameter was also investigated by looking at the earing profile. With increasing temperature the amplitude of earing decreased while the number of ears remained the same, indicating that there is no change in anisotropy with temperature. The cup thickness increases from the bottom of the cup to the flange with a local minimum around the mid-height of the wall. © 2013 Elsevier B.V

    Relationship between obstructive coronary artery disease and abnormal stress testing in patients with paroxysmal or persistent atrial fibrillation

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    Atrial fibrillation (AF) has been linked to the presence of underlying coronary artery disease (CAD). However, whether the higher burden of CAD observed in AF patients translates into higher burden of myocardial ischemia is unknown. In 87 patients (71% male, mean age 61 ± 10 years) with paroxysmal or persistent AF and without history of CAD, MSCT coronary angiography and stress testing (exercise ECG test or myocardial perfusion imaging) were performed. CAD was classified as obstructive (≥50% luminal narrowing) or not. Stress tests were classified as normal or abnormal. A population of 122 patients without history of AF, similar to the AF group as to age, gender, symptomatic status and pre-test likelihood, served as a control group. Based on MSCT, 17% of AF patients were classified as having no CAD, whereas 43% showed non-obstructive CAD and the remaining 40% had obstructive CAD. A positive stress test was observed in 49% of AF patients with obstructive CAD. Among non-AF patients, 34% were classified as having no CAD, while 41% showed non-obstructive CAD and 25% had obstructive CAD (P = 0.013 compared to AF patients). A positive stress test was observed in 48% of non-AF patients with obstructive CAD. In conclusion, the higher burden of CAD observed in AF patients is not associated to higher burden of myocardial ischemia

    Multisensory Memory for Object Identity and Location

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    Researchers have reported that audiovisual object presentation improves memory encoding of object identity in comparison to either auditory or visual object presentation. However, multisensory memory effects on retrieval, on object location, and of other multisensory combinations are yet unknown. We investigated the effects of visuotactile presentation on the encoding and retrieval of object identity memory and object location memory. Participants played an electronic memory card game consisting of an encoding and retrieval phase. In the encoding phase (c) they explored four game cards, which were presented on a computer screen in a two by two arrangement. Participants could touch each card to experience a Morse code presented on the screen (V) and/or via a tactile vibrator attached to the participant’s index finger (T). In the retrieval phase (r), they had to indicate for eight cards if (recognition) and where (relocation) these had been presented earlier. Compared with the visual base line (cV-rV), we found that both ‘multisensory encoding’ (cVT-rV) and ‘multisensory retrieval’ (cV-rVT) significantly improved both recognition and relocation performance. Compared with the tactile base line (cT-rT), we found no multisensory encoding or retrieval effects. This means that vision can benefit from adding touch but not vice versa. We conclude that visuotactile presentation improves memory encoding and retrieval of object identity and location. However, it is not yet clear whether these benefits are due to multisensory integration or simply due to the processing of the same information in multiple sensory modalities

    Implementation of a Multicenter Biobanking Collaboration for Next-Generation Sequencing-Based Biomarker Discovery Based on Fresh Frozen Pretreatment Tumor Tissue Biopsies

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    BACKGROUND: The discovery of novel biomarkers that predict treatment response in advanced cancer patients requires acquisition of high-quality tumor samples. As cancer evolves over time, tissue is ideally obtained before the start of each treatment. Preferably, samples are freshly frozen to allow analysis by next-generation DNA/RNA sequencing (NGS) but also for making other emerging systematic techniques such as proteomics and metabolomics possible. Here, we describe the first 469 image-guided biopsies collected in a large collaboration in The Netherlands (Center for Personalized Cancer Treatment) and show the utility of these specimens for NGS analysis. PATIENTS AND METHODS: Image-guided tumor biopsies were performed in advanced cancer patients. Samples were fresh frozen, vital tumor cellularity was estimated, and DNA was isolated after macrodissection of tumor-rich areas. Safety of the image-guided biopsy procedures was assessed by reporting of serious adverse events within 14 days after the biopsy procedure. RESULTS: Biopsy procedures were generally well tolerated. Major complications occurred in 2.1%, most frequently consisting of pain. In 7.3% of the percutaneous lung biopsies, pneumothorax requiring drainage occurred. The majority of samples (81%) contained a vital tumor percentage of at least 30%, from which at least 500 ng DNA could be isolated in 91%. Given our preset criteria, 74% of samples were of sufficient quality for biomarker discovery. The NGS results in this cohort were in line with those in other groups. CONCLUSION: Image-guided biopsy procedures for biomarker discovery to enable personalized cancer treatment are safe and feasible and yield a highly valuable biobank. The Oncologist 2017;22:33-40Implications for Practice: This study shows that it is safe to perform image-guided biopsy procedures to obtain fresh frozen tumor samples and that it is feasible to use these biopsies for biomarker discovery purposes in a Dutch multicenter collaboration. From the majority of the samples, sufficient DNA could be yielded to perform next-generation sequencing. These results indicate that the way is paved for consortia to prospectively collect fresh frozen tumor tissue
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