915 research outputs found
Vertex evoked potentials in a rating-scale detection task: Relation to signal probability
Vertex evoked potentials were recorded from human subjects performing in an auditory detection task with rating scale responses. Three values of a priori probability of signal presentation were tested. The amplitudes of the N1 and P3 components of the vertex potential associated with correct detections of the signal were found to be systematically related to the strictness of the response criterion and independent of variations in a priori signal probability. No similar evoked potential components were found associated with signal absent judgements (misses and correct rejections) regardless of the confidence level of the judgement or signal probability. These results strongly support the contention that the form of the vertex evoked response is closely correlated with the subject's psychophysical decision regarding the presence or absence of a threshold level signal
Biochemical markers in bronchial carcinoma.
A total of 107 patients with bronchial carcinoma have been studied for the presence of potential circulating tumour markers which might be used as indicators of recurrence after primary treatment. Plasma carcinoembryonic antigen (CEA) levels were estimated in every patient and, after a preliminary hormone screening study, plasma calcitonin (CT) and parathyroid hormone (PTH) levels were assayed in 66 patients. Oat-cell tumours proved to be of particular interest in that CEA levels greater than 40 microgram/l were measured (initially or subsequently) in 40.6 percent and CT levels were elevated in 75 percent. Longitudinal studies point towards the possible use of elevated marker levels as guides to therapy when all other features of recurrent disease are lacking. It is clear that no ideal tumour marker exists for bronchial carcinoma but in an individual case an abnormal level of one or more marker substances may provide a valuable aid to treatment
Immunoreactive calcitonin production by human lung carcinoma cells in culture.
Monolayer cultures have been established from a poorly differentiated carcinoma of the lung. Homogeneous cell growth and morphology have been maintained for over 18 months through more than 80 subculture passages, and the cells have been found to produce both immunoreactive calcitonin and an immunoreactive carcinoembryonic antigen-like material
Impaired Motion Processing in Schizophrenia and the Attenuated Psychosis Syndrome : Etiological and Clinical Implications
The authors thank Gail Silipo, M.A. for assistance in subject recruitment, Raj Sangoi (RT)(R)(MR) and Caxia Hu, M.S., for assistance in MRI scanning and Isabel and Herb Stusser for their generous support. This research was supported by NIMH grant MH084031 (MJH) DA03383 (DCJ).Peer reviewedPostprin
Calcitonin Gene Peptides: The Diagnostic Value of Measurement in Medullary Thyroid Carcinoma
The calcitonin gene encodes a family of peptides, at least three of which normally circulate in man: calcitonin (CT), a calcium-lowering hormone; katacalcin (KC), a peptide of unknown function; and calcitonin gene-related peptide (CGRP), a neuropeptide and potent vasodilator. In a study of 45 patients with medullary thyroid carcinoma (MTC), plasma CGRP was elevated in approximately 50% of cases. Furthermore, CGRP levels did not correlate with CT levels. However, plasma KC was elevated in all cases, with a good correlation with CT levels, as has been noted previously. Measurement of CT or KC appears to be superior to measurement of CGRP for the detection of MTC
Intercomparability of X_(CO_2) and X_(CH_4) from the United States TCCON sites
The Total Carbon Column Observing Network (TCCON) has become the standard for long-term column-averaged measurements of CO_2 and CH_4. Here, we use a pair of portable spectrometers to test for intra-network bias among the four currently operating TCCON sites in the United States (US). A previous analytical error analysis has suggested that the maximum 2σ site-to-site relative (absolute) bias of TCCON should be less than 0.2% (0.8ppm) in X_(CO_2) and 0.4% (7ppb) in X_(CH_4). We find here experimentally that the 95% confidence intervals for maximum pairwise site-to-site bias among the four US TCCON sites are 0.05–0.14% for X_(CO_2) and 0.08–0.24% for X_(CH_4). This is close to the limit of the bias we can detect using this methodology
Representing environmental harm and resistance on Twitter: The case of the TAP pipeline
This research explores a new methodological path for doing green cultural criminological research via social media. It provides original case-study data and aims to stimulate further empirical and theoretical debate. In particular, the study explores how Twitter users have represented the harms related to an ongoing pipeline project in Italy (referred to as TAP), and the resistance to those harms. To these ends, it offers a virtual and visual ethnography of Twitter posts and posted images
Beliefs about the Minds of Others Influence How We Process Sensory Information
Attending where others gaze is one of the most fundamental mechanisms of social cognition. The present study is the first to examine the impact of the attribution of mind to others on gaze-guided attentional orienting and its ERP correlates. Using a paradigm in which attention was guided to a location by the gaze of a centrally presented face, we manipulated participants' beliefs about the gazer: gaze behavior was believed to result either from operations of a mind or from a machine. In Experiment 1, beliefs were manipulated by cue identity (human or robot), while in Experiment 2, cue identity (robot) remained identical across conditions and beliefs were manipulated solely via instruction, which was irrelevant to the task. ERP results and behavior showed that participants' attention was guided by gaze only when gaze was believed to be controlled by a human. Specifically, the P1 was more enhanced for validly, relative to invalidly, cued targets only when participants believed the gaze behavior was the result of a mind, rather than of a machine. This shows that sensory gain control can be influenced by higher-order (task-irrelevant) beliefs about the observed scene. We propose a new interdisciplinary model of social attention, which integrates ideas from cognitive and social neuroscience, as well as philosophy in order to provide a framework for understanding a crucial aspect of how humans' beliefs about the observed scene influence sensory processing
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