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Discover the most talked about and latest scientific content & concepts.

Concept: First-order logic

683

We study fifteen months of human mobility data for one and a half million individuals and find that human mobility traces are highly unique. In fact, in a dataset where the location of an individual is specified hourly, and with a spatial resolution equal to that given by the carrier’s antennas, four spatio-temporal points are enough to uniquely identify 95% of the individuals. We coarsen the data spatially and temporally to find a formula for the uniqueness of human mobility traces given their resolution and the available outside information. This formula shows that the uniqueness of mobility traces decays approximately as the 1/10 power of their resolution. Hence, even coarse datasets provide little anonymity. These findings represent fundamental constraints to an individual’s privacy and have important implications for the design of frameworks and institutions dedicated to protect the privacy of individuals.

Concepts: Optics, Data set, Law, First-order logic

167

The identification and surveillance of patients with preneoplastic lesions at high risk of progressing to gastric cancer (GC) represents the most effective way of reducing the burden of GC. The incomplete type of intestinal metaplasia (IM) could be considered as the best candidate for surveillance. However, the usefulness of subtyping of IM has been considered by some authors as limited and inconsistent. A search was carried out to identify all cross-sectional (n= 14) and follow-up (n= 10) studies that assessed the risk of GC among subjects with different types of IM. Out of the 14 cross-sectional studies, 13 reported that the prevalence of incomplete IM was statistically significantly higher in GC than in other gastric lesions. Out of the 10 follow-up studies, 6 found a statistically significant association between incomplete IM and subsequent GC risk. The relative risks of GC were from 4 to 11-fold higher for the presence of incomplete type in comparison to complete type or in comparison to the absence of incomplete type, among the studies that reported the magnitude of the risk. According to this comprehensive review, most of the scientific evidence supports the utility of subtyping IM as a predictor of GC risk. Recognizing its usefulness by gastroenterologists should encourage pathologists to subtype IM. © 2012 Wiley Periodicals, Inc.

Concepts: Scientific method, Epidemiology, Decision theory, First-order logic, Risk aversion, Type theory, Polymorphism in object-oriented programming, Subtype polymorphism

27

Abstract Psychologists have long assumed a connection between traumatic experience and psychological dissociation. This hypothesis is referred to as the Trauma Model of dissociation. In the last decade, a series of papers have been published that question this traditional causal link, proposing an alternative Fantasy Model of dissociation. In this research, the relationship among dissociation, suggestibility, and fantasy proneness were examined. Suggestibility was measured through the Gudjonsson Scale of Interrogative Suggestibility (GSS), as well as an autobiographically based version of this measure based on the events of September 11, 2001. Consistent with prior research and with the Trauma Model, dissociation correlated positively with trauma severity (r = .32, p < .01) and fantasy proneness (r = .60, p < .01). Inconsistent with the Fantasy Model, dissociation did not correlate with the neutral form of the Gudjonsson, and correlated negatively (r = -.24, p < .05) with the trauma-focused form of this suggestibility measure. Although some participants did become quite emotional during the procedure, the risk/benefit ratio was perceived by almost all participants to be positive, with more reactive individuals evaluating the procedure more positively. The results consistently support the Trauma Model of dissociation and fail to support the Fantasy Model of dissociation.

Concepts: Psychology, Measurement, Psychological trauma, First-order logic, Metalogic, Dissociation, Gödel's incompleteness theorems, September 11

27

A simple method for quantification of contrast in a fingerprint is proposed. Contrast is defined as the average difference in intensity of pixels between valleys and ridges in a fingerprint. It is quantified from a scanner-acquired image of the fingerprint using a histogram function of Adobe Photoshop. The method was validated with black inked prints and marks developed with aluminum powder. Moreover, we tested resistance of the method to rater-dependent errors and dependence of the measurements on the resolution of an image and the model of the scanner. For both groups of fingerprints, the method gave coherent and easily interpretable quantitative values for contrast. There were no significant differences between measurements performed by different raters and by the same rater in a test-retest procedure. However, the method was found to be instrument dependent, as measurements were significantly affected by image resolution and the model of the scanner.

Concepts: Function, Difference, First-order logic, Display resolution, Object-oriented programming, Method, RGB color model, Adobe Photoshop

27

To pin down the processing characteristics of symmetry and closure in contour processing, we investigated their ability to activate rapid motor responses in a primed flanker task. In three experiments, participants selected as quickly and accurately as possible the one of two target contours possessing symmetry or closure. Target pairs were preceded by prime pairs whose spatial arrangement was consistent or inconsistent with respect to the required response. We tested for the efficiency and automaticity of symmetry and closure processing. For both cues, priming effects were present in full magnitude in the fastest motor responses consistent with a simple feedforward model. Priming effects from symmetry cues were independent of skewing and the orientation of their symmetry axis but sometimes failed to increase with increasing prime-target interval. We conclude that closure and (possibly) viewpoint-independent symmetry cues are extracted rapidly during the first feedforward wave of neuronal processing.

Concepts: Time, Vector space, First-order logic, Metalogic, Consistency, Gödel's incompleteness theorems

25

Abstract The purpose of this study was to apply RQA (recurrence quantification analysis) on hypnotic electroencephalograph (EEG) signals recorded after hypnotic induction while subjects were doing standard tasks of the Waterloo-Stanford Group Scale (WSGS) of hypnotic susceptibility. Then recurrence quantifiers were used to analyse the influence of hypnotic depth on EEGs. By the application of this method, the capability of tasks to distinguish subjects of different hypnotizability levels was determined. Besides, medium hypnotizable subjects showed the highest disposition to be inducted by hypnotizer. Similarities between brain governing dynamics during tasks of the same type were also observed. The present study demonstrated two remarkable innovations; investigating the EEGs of the hypnotized as doing mental tasks of Waterloo-Stanford Group Scale (WSGS) and applying RQA on hypnotic EEGs.

Concepts: Scientific method, Signal processing, Electroencephalography, First-order logic, Logic, Hypnosis, Recurrence quantification analysis, Hypnotic susceptibility

24

Crisis resolution teams (CRTs) can provide effective home-based treatment for acute mental health crises, although critical ingredients of the model have not been clearly identified, and implementation has been inconsistent. In order to inform development of a more highly specified CRT model that meets service users' needs, this study used qualitative methods to investigate stakeholders' experiences and views of CRTs, and what is important in good quality home-based crisis care.

Concepts: Psychology, Educational psychology, First-order logic, Logic, Service

24

Parent participation in community-based child mental health services is an important yet understudied process associated with treatment effectiveness. This paper describes the development and psychometrics of the Parent Participation Engagement Measure in a sample of 1374 parents and 563 youth receiving publicly-funded mental health services. Analyses indicated excellent internal consistency, and model fit indices/factor loadings supported a one-factor model. Convergent and discriminant validity were supported, although some coefficients were modest in magnitude. Psychometric results were consistent for Caucasian versus Hispanic, parent versus youth, and English versus Spanish-language respondents. The clinical and research utility of this measure are discussed.

Concepts: Clinical trial, Mental health, Educational psychology, Psychometrics, First-order logic, Validity, Reliability, Cronbach's alpha

20

The extraction of general knowledge from individual episodes is critical if we are to learn new knowledge or abilities. Here we uncover some of the key cognitive mechanisms that characterise this process in the domain of language learning. In five experiments adult participants learned new morphological units embedded in fictitious words created by attaching new affixes (e.g., -afe) to familiar word stems (e.g., “sleepafe is a participant in a study about the effects of sleep”). Participants' ability to generalise semantic knowledge about the affixes was tested using tasks requiring the comprehension and production of novel words containing a trained affix (e.g., sailafe). We manipulated the delay between training and test (Experiment 1), the number of unique exemplars provided for each affix during training (Experiment 2), and the consistency of the form-to-meaning mapping of the affixes (Experiments 3-5). In a task where speeded online language processing is required (semantic priming), generalisation was achieved only after a memory consolidation opportunity following training, and only if the training included a sufficient number of unique exemplars. Semantic inconsistency disrupted speeded generalisation unless consolidation was allowed to operate on one of the two affix-meanings before introducing inconsistencies. In contrast, in tasks that required slow, deliberate reasoning, generalisation could be achieved largely irrespective of the above constraints. These findings point to two different mechanisms of generalisation that have different cognitive demands and rely on different types of memory representations.

Concepts: Psychology, Cognition, Memory, Linguistics, Language, First-order logic, Learning, Logic

12

The majority of anthropological studies on dermatoglyphics examine the heritability and inter-population variation of Level 1 detail (e.g., pattern type, total ridge count), while forensic scientists concentrate on individual uniqueness of Level 2 and 3 detail (e.g., minutiae and pores, respectively) used for positive identification. The present study bridges the gap between researcher-practitioner by examining sex, ancestral, and pattern type variation of Level 2 detail (e.g., minutiae).

Concepts: Genetics, First-order logic, Cultural studies, Forensic science, Sherlock Holmes, Fingerprint, Profiling practices, Minutiae