Home About us Contact
|
Home About us Contact | ||
|
|
||
Processing System (processing + system)
Selected AbstractsPrejudice Control and Interracial Relations: The Role of Motivation to Respond Without PrejudiceJOURNAL OF PERSONALITY, Issue 5 2009David A. Butz ABSTRACT A decade of research indicates that individual differences in motivation to respond without prejudice have important implications for the control of prejudice and interracial relations. In reviewing this work, we draw on W. Mischel and Y. Shoda's (1995, 1999) Cognitive,Affective Processing System (CAPS) to demonstrate that people with varying sources of motivation to respond without prejudice respond in distinct ways to situational cues, resulting in differing situation,behavior profiles in interracial contexts. People whose motivation is self-determined (i.e., the internally motivated) effectively control prejudice across situations and strive for positive interracial interactions. In contrast, people who respond without prejudice to avoid social sanction (i.e., the primarily externally motivated) consistently fail at regulating difficult to control prejudice and respond with anxiety and avoidance in interracial interactions. We further consider the nature of the cognitive,affective units of personality associated with motivation to respond without prejudice and their implications for the quality of interracial relations. [source] How does the brain learn language?DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2 2000Insights from the study of children with, without language impairment Neurobiological studies have generated new ways of thinking about development of brain structure and function. Development involves more than just growth from simple to complex structures. The initial over-abundance of neurons and synaptic connections is subsequently pruned of those that are non-functional. In addition, as behavioural and cognitive functions emerge and become automatized, the underlying brain representations are reorganized. In this paper, I shall argue that these different modes of neurodevelopmental change provide a useful metaphor for examining language acquisition. It will be argued that language acquisition can involve learning to ignore and inhibit irrelevant information, as well as forming new ways of representing complex information economically. Modular organization is not present from the outset, but develops gradually. This analysis suggests a new way of assessing specific language impairment (SLI). There has been much debate as to whether children with SLI lack specific modular components of a language processing system. I propose instead that these children persist in using inefficient ways of representing language. Finally, I consider what we know about the neurobiological basis of such a deficit. There is mounting evidence that children with SLI have subtle structural anomalies affecting the language areas of the brain, which are largely genetically determined. We should not, however, conclude that the language difficulties are immutable. [source] Sensitivity to visual and auditory stimuli in children with developmental dyslexiaDYSLEXIA, Issue 2 2008Bernardine King Abstract This study considered the extent to which 23 children with dyslexia differed from 23 reading age (RA) and 23 chronological age (CA) matched controls in their ability to make temporal judgements about auditory and visual sequences of stimuli, and in the speed of their reactions to the onsets and offsets of visual and auditory stimuli. The children with dyslexia were slower (p,=,0.039) than the CA controls in their reactions to non-verbal auditory onsets (tones), were less able to recognize the first stimulus of a sequence of tones (p,=,0.022), and were less accurate in identifying the initial phoneme of a sequence of three (p,<,0.001). These characteristics may be manifestations of an impaired temporal processing system for rapid auditory stimuli. CA controls responded more quickly to tone onsets than to tone offsets (p,=,0.025), but the dyslexic and RA groups showed no significant difference (p,>,0.05) in their reaction times to onsets and offsets of these non-verbal auditory stimuli. Dyslexic readers showed impairment compared with CA controls in responding to the last of a sequence of three non-verbal visual stimuli (shapes), p,=,0.02. Reaction times in the visual and auditory onset and offset tasks were richly intercorrelated in the control groups, but the dyslexic group did not show as many significant correlations in reaction times between the auditory and visual domains, or between the onset and offset RTs within each modality. These results suggest that there may be a less integrated cross-modal and intra-modal temporal system in children with dyslexia than in controls. In many of the measures in this study, the performance of the dyslexic group resembled that of the RA control group but differed from CA controls, which implies a developmental delay. The possibility that such a cognitive delay may be related to an underlying neurological disorder is discussed. Copyright © 2007 John Wiley & Sons, Ltd. [source] Spatial and temporal analysis of fMRI data on word and sentence readingEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007Sven Haller Abstract Written language comprehension at the word and the sentence level was analysed by the combination of spatial and temporal analysis of functional magnetic resonance imaging (fMRI). Spatial analysis was performed via general linear modelling (GLM). Concerning the temporal analysis, local differences in neurovascular coupling may confound a direct comparison of blood oxygenation level-dependent (BOLD) response estimates between regions. To avoid this problem, we parametrically varied linguistic task demands and compared only task-induced within-region BOLD response differences across areas. We reasoned that, in a hierarchical processing system, increasing task demands at lower processing levels induce delayed onset of higher-level processes in corresponding areas. The flow of activation is thus reflected in the size of task-induced delay increases. We estimated BOLD response delay and duration for each voxel and each participant by fitting a model function to the event-related average BOLD response. The GLM showed increasing activations with increasing linguistic demands dominantly in the left inferior frontal gyrus (IFG) and the left superior temporal gyrus (STG). The combination of spatial and temporal analysis allowed a functional differentiation of IFG subregions involved in written language comprehension. Ventral IFG region (BA 47) and STG subserve earlier processing stages than two dorsal IFG regions (BA 44 and 45). This is in accordance with the assumed early lexical semantic and late syntactic processing of these regions and illustrates the complementary information provided by spatial and temporal fMRI data analysis of the same data set. [source] Incident Monitoring in Emergency Departments An Australian ModelACADEMIC EMERGENCY MEDICINE, Issue 11 2000FIFEM, John Vinen FACEM Abstract. The specialty-based study of incidents, adverse events, and errors in medicine has largely occurred in anesthesia and to a lesser extent in intensive care and psychiatry. Few studies have specifically addressed the problem in emergency medicine (EM). Because of the significant risks, the resulting adverse outcome, and the high degree of preventability of errors occurring in the emergency department (ED), it is essential that an incident monitoring system be part of the ED's risk management program. The combination of time pressure, uncertainty, complexity, and workload means the ED is a high-risk environment. The delivery of high-quality emergency care is dependent on having an effective patient processing system in place and, because EM is a "systems-dependent" specialty, the environment lends itself to improvements to the system (re-engineering) to improve the safety of the environment given that the majority of errors in the ED are probably the result of failures of the system. This paper describes an existing incident monitoring system that has recently been adopted by six EDs in Australia. It was developed as a result of a similar successful program in anesthesia, and funded by the Federal Department of Health of Australia. Incorporating incident monitoring and analysis to identify causative factors of incidents and the subsequent implementation of corrective strategies as part of the ED risk management program may result in improvement in the quality of care through a reduction in the frequency of incidents. [source] Quality of applesauces processed by pulsed electric fields and HTST pasteurisation,INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2009Z. T. Jin Summary A pilot plant scale continuous flow pulsed electric field (PEF) and high temperature short time (HTST) processing system was integrated with an aseptic packaging machine. Fuji applesauce and blueberry applesauce were processed with PEF followed by HTST pasteurisation (PEF + HTST). PEF + HTST processed Fuji applesauce from fresh Fuji apples demonstrated high and stable sensory scores during 9 months storage at 27 °C, and had comparative sensory quality with Meal Read-to-Eat (MRE) and commercial applesauce products stored at 4 °C. PEF + HTST processed blueberry applesauce from pre-pasteurised materials had lower sensory scores than PEF + HTST processed Fuji applesauce and was significantly less stable during the storage at 27 °C. PEF + HTST processed applesauces had aerobic count and mould and yeast count of <10 cfu mL,1 during storage. Electrical conductivity, pH and °Brix, were not significantly changed throughout storage time (P > 0.05). [source] RTSVC: Real-time system for visual control of robotsINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 4 2008Eusebio Bugarin Abstract This article presents an image processing system that can work in hard real-time. Compared with systems that use the traditional multiprocessor architecture approach, this computer system takes advantage on recent technological advances and it is designed to work with a single processor PC under RTLinux. Its programming environment is similar to C programming language and it offers a friendly graphical user interface. The performance of the system is illustrated by means of experiments applied to visual guidance of mobile robots via velocity fields using a fixed high-speed camera. The experiments were carried out with a strict sampling frequency of 100 Hz. © 2008 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 18, 251,256, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). [source] Adaptive control for edge alignment in polyester film processingADVANCES IN POLYMER TECHNOLOGY, Issue 3 2007Chang-Chiun Huang Abstract Edge alignment of polyester (PET) films is important for achieving product quality and processing speed in winding, coating, drying, and other processes. The edge alignment can be achieved by lateral deflection control, provided that the film tension and transport speed are even at desired values. This article aims to correct the lateral deflection of films by designing robust controllers to swivel the guiding rollers and to maintain even tension and speed at target levels. The self-tuning neuro-proportional integral derivative controller and adaptive high-gain output feedback controller are adopted to guide the lateral deflection so that the film aligns at the desired position. A control scheme, neuron controller by associative learning, is used for maintaining tension and speed control. These strategies are applied to a simplified PET film processing system. The experimental results demonstrate that in our setup, the control schemes can effectively alleviate not only the lateral deflection but also the tension and speed fluctuation at target levels. © 2008 Wiley Periodicals, Inc. Adv Polym Techn 26:153,162, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20096 [source] A bird's eye view of the peppered mothJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2000Majerus Industrial melanism in Biston betularia is one of the best known examples of the role of natural selection in evolution and has received considerable scrutiny for many years. The rise in frequency of the dark form of the moth (carbonaria) and a decrease in the pale form (typica) was the result of differential predation by birds, the melanic form being more cyptic than typica in industrial areas where the tree bark was darkened by air pollution. One important aspect of early work evaluating the relative crypsis of the forms of B. betularia on tree trunks with different lichen flora was the reliance on human observers. Humans, however, do not have the same visual capabilities as birds. Birds have well-developed ultraviolet (UV) vision, an important component of their colour processing system that affects many aspects of behaviour, including prey detection. We examined the UV characteristics of the two forms of B. betularia and a number of foliose and crustose lichens. In human visible light the speckled form typica appeared cyptic when seen against a background of foliose lichen, whereas the dark form carbonaria was conspicuous. Under UV light the situation was reversed. The foliose lichens absorbed UV and appeared dark as did carbonaria. Typica, however, reflected UV and was conspicuous. Against crustose lichens, typica was less visible than carbonaria in both visible and UV light. These findings are considered in relation to the distribution and recolonization of trees by lichens and the resting behaviour of B. betularia. [source] Expression of human ,-defensins-1 and -2 peptides in unresolved chronic periodontitisJOURNAL OF PERIODONTAL RESEARCH, Issue 4 2004Qian Lu Background:, Human ,-defensins (hBDs) are antimicrobial peptides which contribute to host innate immunity by disrupting the membrane integrity of a broad spectrum of microorganisms. Objectives:, This study aimed to determine the expression profiles of hBD-1 and -2 peptides in gingiva and to assess the possible relations of these antimicrobial peptides with periodontal health and disease. Methods:, Seven periodontally healthy subjects and 22 patients with unresolved chronic periodontitis were recruited and the gingival biopsies collected consisted of healthy tissues from the healthy subjects (HT-C); periodontal pocket tissues (PoT) and inflamed connective tissues (ICT) from the base of pocket, i.e. granulation tissues, as well as clinically healthy tissues (HT-P) from the adjacent clinically healthy sites from the patients. The expression of hBD-1 and -2 peptides was detected by immunohistochemistry and quantitatively analyzed with a computerized image processing system. Results:, Both hBD-1 and -2 peptides were detected in all periodontally healthy subjects, while hBD-1 was detected in all patients and hBD-2 was found in most of the patients. Their expression was mainly confined to the granular and spinous layers of gingival epithelium, in which hBD-1 was detected in both intercellular spaces and cytoplasm, whereas hBD-2 was mainly observed in the cytoplasm. HT-C expressed significantly higher levels of hBD-2 than HT-P (p < 0.05). Within the patients, both defensins were up-regulated significantly in PoT as compared with the adjacent HT-P (p < 0.05). Conclusions:, The present study showed that hBD-1 and -2 were frequently expressed in the granular and spinous layers of gingival epithelia and their expression may be associated with periodontal health and disease. [source] Squirrel monkey chuck call: vocal response to playback chucks based on acoustic structure and affiliative relationship with the callerAMERICAN JOURNAL OF PRIMATOLOGY, Issue 3 2002Joseph Soltis Abstract Adult female squirrel monkeys (genus Saimiri) that are socially familiar often exchange the chuck vocalization, which differs acoustically across individuals. We used behavioral observations, vocalization playback experiments, and analysis of the acoustic properties of vocalizations to investigate the effect of caller identity and acoustic structure on vocal response to playback chucks in two all-female social groups (n=10 females). Females were most likely to respond with a chuck to the playback chucks of their closely affiliated partners compared to those of nonaffiliated group members. This shows for the first time that the chuck stimulus alone is sufficient to elicit a chuck response from a female's affiliated partner. Additionally, females responded with a chuck mostly to familiar playback chucks from their own group and least to playbacks of silent controls. Unfamiliar playback chucks from the same species and a different squirrel monkey species elicited chuck responses intermediate between familiar chucks and silent controls. Post-hoc discriminant function analyses provide preliminary evidence that females are most likely to respond to unfamiliar chucks when those chucks are close in acoustic structure to familiar chucks from their own social group. These results provide a provisional explanation for error in the squirrel monkey signal processing system, in which unfamiliar chucks never heard before nevertheless elicit a chuck response if they are similar in acoustic structure to familiar group chucks. © 2002 Wiley-Liss, Inc. [source] Optimal control of fuel processing system using generalized linear quadratic Gaussian and loop transfer recovery method,,ASIAN JOURNAL OF CONTROL, Issue 5 2010Huan-Liang Tsai Abstract This paper proposes an optimal control system that consists of both feedforward and state-feedback controllers designed using a generalized linear quadratic Gaussian and loop transfer recovery (GLQG/LTR) method for a fuel processing system (FPS). This FPS uses natural gas as fuel and reacts with atmospheric air through a catalytic partial oxidation (CPO) response. The control objective is focused on the regulatory performance of the output vector in response to a desired stack current command in the face of load variation. The proposed method provides another degree of freedom in the optimal control design and gives the compensated system a prescribed degree of stability. Finally, the numerical simulations of compensated FPS reveal that the proposed method displays better performance and robustness properties in both time-domain and frequency-domain responses than those obtained by the traditional LQ Method. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society [source] Computational Evidence for the Subitizing Phenomenon as an Emergent Property of the Human Cognitive ArchitectureCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 1 2000Scott A. Peterson A computational modeling approach was used to test one possible explanation for the limited capacity of the subitizing phenomenon. Most existing models of this phenomenon associate the subitizing span with an assumed structural limitation of the human information processing system. In contrast, we show how this limit might emerge as the combinatorics of the space of enumeration problems interacts with the human cognitive architecture in the context of an enumeration task. Subitizing-like behavior was generated in two different models of enumeration, one based on the ACT-R cognitive architecture and the other based on the principles of parallel distributed processing (PDP). Our results provide good qualitative fits to results obtained in a variety of empirical studies. [source] Cognitive visual dysfunctions in preterm children with periventricular leukomalaciaDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 12 2009ELISA FAZZI MD PHD Aim, Cognitive visual dysfunctions (CVDs) reflect an impairment of the capacity to process visual information. The question of whether CVDs might be classifiable according to the nature and distribution of the underlying brain damage is an intriguing one in child neuropsychology. Method, We studied 22 children born preterm (12 males, 10 females; mean age at examination 8y, range 6,15y; mean gestational age 30wks, range 28,36wks) with periventricular leukomalacia, spastic diplegia, normal intelligence (mean Full-scale IQ 84; mean Verbal IQ 97; mean Performance IQ 74), and normal visual acuity, focusing on higher visual functions. Brain magnetic resonance images (MRI) were analysed to establish the presence of lesions along the primary optic pathway, in the occipitoparietal and occipitotemporal regions. Results, Most children displayed an uneven cognitive profile, with deficits in visual object recognition, visual imagery, visual,spatial skills, and visual memory, and sparing of visual associative abilities, non-verbal intelligence, and face and letter recognition. Conventional brain MRI did not document major alterations of parietal and temporal white matter, or cortical alteration of areas involved in visual associative functions. Interpretation, We suggest a widespread involvement of higher visual processing systems, involving both the ventral and dorsal streams, in preterm children with periventricular leukomalacia. The lack of major alterations on conventional MRI does not exclude the possibility of malfunctioning of higher visual processing systems, expressing itself through discrete CVDs. Possible mechanisms underlying these neuropsychological deficits are discussed. [source] FDTD analysis of switching characteristics in magnetooptic functional devices using magnetostatic surface wavesELECTRICAL ENGINEERING IN JAPAN, Issue 1 2008Atsushi Noguchi Abstract Collinear magnetooptic interaction with magnetostatic surface waves (MSSW) can be used for wavelength-selective switches, wavelength filters, and frequency shifters in wavelength-division-multiplexed (WDM) photonic networks and optical processing systems. The switching efficiency can be improved with a multilayer waveguide structure. To investigate the dynamic switching characteristics, the FDTD method was employed. The mode conversion between TE and TM mode was successfully demonstrated with FDTD simulation. The filtering characteristics were also evaluated. The FDTD results were compared with the result from the coupled mode theory, and good agreement was obtained. Switching of an optical pulse was also demonstrated by the FDTD method. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(1): 40,47, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20501 [source] The heterogeneous distribution of functional synaptic connections in rat hippocampal dissociated neuron culturesELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 6 2009Suguru N. Kudoh Abstract The dynamics of functional synaptic connections are critical for information processing systems in the brain, such as perception and learning. Using rat hippocampal cells cultured on multielectrode arrays, we investigated the spatiotemporal pattern of spontaneous action potentials. The neurons developed connections and a characteristic high-frequency bursting (HFB) activity was observed transiently. After the period of HFB activity, the distribution of spontaneous activity changed drastically with the appearance of neurons with frequent electrical activity and neurons with little activity in the network. The functional connections of all the combinations of recorded spike trains were estimated and depicted simultaneously in a Connection Map. This map revealed that each culture contained hublike neurons with many functional connections, suggesting that the cultures of dissociated rat hippocampal neurons on multielectrode arrays formed heterogeneous networks of functional connections. In addition, the functional connections were drastically reorganized after the induction of synaptic potentiation, and novel hub neurons emerged. These results indicate that spontaneous activity is enough to construct dynamic assemblies of neurons connected to each other by functional synaptic connections, and that synaptic potentiation can induce reorganization of such assemblies of neurons. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 92(6): 41,49, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10063 [source] A comparison of five fMRI protocols for mapping speech comprehension systemsEPILEPSIA, Issue 12 2008Jeffrey R. Binder Summary Aims:, Many fMRI protocols for localizing speech comprehension have been described, but there has been little quantitative comparison of these methods. We compared five such protocols in terms of areas activated, extent of activation, and lateralization. Methods:, fMRI BOLD signals were measured in 26 healthy adults during passive listening and active tasks using words and tones. Contrasts were designed to identify speech perception and semantic processing systems. Activation extent and lateralization were quantified by counting activated voxels in each hemisphere for each participant. Results:, Passive listening to words produced bilateral superior temporal activation. After controlling for prelinguistic auditory processing, only a small area in the left superior temporal sulcus responded selectively to speech. Active tasks engaged an extensive, bilateral attention, and executive processing network. Optimal results (consistent activation and strongly lateralized pattern) were obtained by contrasting an active semantic decision task with a tone decision task. There was striking similarity between the network of brain regions activated by the semantic task and the network of brain regions that showed task-induced deactivation, suggesting that semantic processing occurs during the resting state. Conclusions:, fMRI protocols for mapping speech comprehension systems differ dramatically in pattern, extent, and lateralization of activation. Brain regions involved in semantic processing were identified only when an active, nonlinguistic task was used as a baseline, supporting the notion that semantic processing occurs whenever attentional resources are not controlled. Identification of these lexical-semantic regions is particularly important for predicting language outcome in patients undergoing temporal lobe surgery. [source] DYNAMIC MODELING OF RETORT PROCESSING USING NEURAL NETWORKSJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2002C. R. CHEN ABSTRACT Two neural network approaches , a moving-window and hybrid neural network , which combine neural network with polynomial regression models, were used for modeling F(t) and Qv(t) dynamic functions under constant retort temperature processing. The dynamic functions involved six variables: retort temperature (116,132C), thermal diffusivity (1.5,2.3 × 10,7m2/s), can radius (40,61 mm), can height (40,61 mm), and quality kinetic parameters z (15,39C) and D (150,250 min). A computer simulation designed for process calculations of food thermal processing systems was used to provide the fundamental data for training and generalization of ANN models. Training data and testing data were constructed by both second order central composite design and orthogonal array, respectively. The optimal configurations of ANN models were obtained by varying the number of hidden layers, number of neurons in hidden layer and learning runs, and a combination of learning rules and transfer function. Results demonstrated that both neural network models well described the F(t) and Qv(t) dynamic functions, but moving-window network had better modeling performance than the hybrid ANN models. By comparison of the configuration parameters, moving-window ANN models required more neurons in the hidden layer and more learning runs for training than the hybrid ANN models. [source] Failure Modes with Point Loading of Three Commercially Available Denture TeethJOURNAL OF PROSTHODONTICS, Issue 6 2008Andrew R. Moffitt DDS Abstract Purpose: A common problem associated with implant-supported prostheses is the fracture of denture teeth. This study was designed to compare the fracture modes of three denture teeth by compressive load at a 30° off-axis angle. Material and Methods: Three denture teeth (Vident Duostat, Ivoclar Vivadent, and Dentsply Trubyte) processed to two denture base processing systems [injection-molded (IM) SR-Ivocap system and compression-molded (CM) denture base resin] were evaluated. Each specimen was processed to a metal framework. Ultimate failure strength of each system when point loaded at a 30° off-axis angle was recorded, along with a visual inspection of each specimen. Results: The average load fracture for each group was (in N): Vident CM 1106.97 ± 223.20, Vident IM 1168.18 ± 322.52, Dentsply CM 1098.08 ± 286.32, Dentsply IM 1023.80 ± 282.45, Ivoclar CM 1616.98 ± 204.87, and Ivoclar IM 1373.54 ± 282.58. There was a significant difference between the groups and the Ivoclar CM group. The Ivoclar CM group had the highest average load force, and the Dentsply IM group had the lowest average load force. On average, the teeth within the groups fractured at a higher compression force than the average maximum occlusal force in natural dentition. Dentsply and Vident denture teeth fractured more horizontally, and the Ivoclar denture teeth fractured more vertically within the groups. There was no significant difference among the groups between the IM and CM processing methods. Conclusions: In the present in vitro study, all specimens were able to withstand 30° off-axis loading with the exception of one specimen. With these results, this would indicate that these denture teeth are able to withstand normal occlusal forces. [source] Overseeing organizations: configuring action and its environmentTHE BRITISH JOURNAL OF SOCIOLOGY, Issue 2 2002Christian Heath ABSTRACT Despite the widespread deployment of CCTV through most major cities and towns in great Britain, and the importance of surveillance to contemporary debates within the social sciences, there remains relatively little detailed research concerned with the practical use of these technologies in the workplace. In this paper, we examine how personnel in the operation rooms in London Underground use CCTV and related equipment to identify problems and events and to develop a co-ordinated response. In particular, we consider how personnel configure scenes to make sense of and interpret the conduct of the travelling public in organizationally relevant ways, and how they shape the ways in which both passengers and staff see and respond to each others' actions. In addressing how personnel constitute the sense and significance of CCTV images, we reflect on the development of information processing systems which are designed to automatically detect conduct and events. [source] Incentive-elicited mesolimbic activation and externalizing symptomatology in adolescentsTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 7 2010James M. Bjork Background:, Opponent-process theories of externalizing disorders (ExD) attribute them to some combination of overactive reward processing systems and/or underactive behavior inhibition systems. Reward processing has been indexed by recruitment of incentive-motivational neurocircuitry of the ventral striatum (VS), including nucleus accumbens (NAcc). Methods:, We used functional magnetic resonance imaging (fMRI) with an incentive task to determine whether externalizing symptomatology in adolescence is correlated with an enhanced VS recruitment by cues for rewards, or by deliveries of rewards. Twelve community-recruited adolescents with externalizing disorders (AED) and 12 age/gender-matched controls responded to targets to win or avoid losing $0, $0.20, $1, $5, or an unknown amount (ranging from $0.20 to $5). Results:, Cues to respond for rewards activated the NAcc (relative to cues for no incentive), in both subject groups similarly, with greatest NAcc recruitment by cues for the largest reward. Loss-anticipatory NAcc signal increase was detected in a volume-of-interest analysis , but this increase occurred only in trials when subjects hit the target. Relative to controls, AED showed significantly elevated NAcc activation by a linear contrast between reward notification versus notification of failure to win reward. In a post hoc reanalysis, VS and pregenual anterior cingulate activation by the reward versus non-reward outcome contrast also directly correlated with Child Behavior Checklist (CBCL) Externalizing total scores (across all subjects) in lieu of a binary diagnosis. Finally, both groups showed right insula activation by loss notifications (contrasted with avoided losses). Conclusions:, Externalizing behavior, whether assessed dimensionally with a questionnaire, or in the form of a diagnostic categorization, is associated with an exaggerated limbic response to outcomes of reward-directed behavior. This could be a neurobiological signature of the behavioral sensitivity to laboratory reward delivery that is characteristic of children with externalizing symptomatology. Of interest is future research on incentive-motivational processing in more severe, clinically referred AED. [source] Retrieval validation during the European Aqua Thermodynamic ExperimentTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue S3 2007Daniel K. Zhou Abstract Atmospheric and surface thermodynamic parameters retrieved with advanced hyperspectral remote sensors aboard Earth observing satellites are critical to weather prediction and scientific research. The retrieval algorithms and retrieved parameters from satellite sounders must be validated to demonstrate the capability and accuracy of both observation and data processing systems. The European Aqua Thermodynamic Experiment (EAQUATE) was conducted not only for validation of the Atmospheric InfraRed Sounder on the Aqua satellite, but also for assessment of validation systems of both ground-based and aircraft-based instruments that will be used for other satellite systems, such as the Infrared Atmospheric Sounding Interferometer on the European MetOp satellite, the Cross-track Infrared Sounder from the National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project and the continuing series of NPOESS satellites. Detailed intercomparisons were conducted and presented using different retrieval methodologies: measurements from airborne ultraspectral Fourier transform spectrometers, aircraft in situ instruments, dedicated dropsondes and radiosondes, ground-based Raman lidar, as well as the European Centre for Medium-range Weather Forecasting modelled thermal structures. The results of this study not only illustrate the quality of the measurements and retrieval products, but also demonstrate the capability of the validation systems put in place to validate current and future hyperspectral sounding instruments and their scientific products. Copyright © 2007 Royal Meteorological Society [source] Automatic Extraction of ECG Strips from Continuous 12-lead Holter Recordings for QT Analysis at Prescheduled versus Optimized Time PointsANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2009Fabio Badilini Ph.D. Background: Continuous 12-lead ECG monitoring (Holter) in early-phase pharmaceutical studies is today widely used as an ideal platform to extract discrete ECGs for analysis. The extraction process is typically performed manually by trained readers using commercial Holter processing systems. Methods: Antares, a novel method for automatic 12-lead extraction from continuous Holter recordings applying minimal noise criteria and heart-rate stability conditions is presented. A set of 12-lead Holter recordings from healthy subjects administered with sotalol is used to compare ECG extractions at fixed time points with ECG extractions generated by Antares optimizing noise and heart rate inside 5 minute windows centered around each expected time point of interest. Results: Global, low- and high-frequency noise content of extracted ECGs was significantly reduced via optimized approach by Antares. Heart rate was also slightly reduced (from 69 ± 13 to 64 ± 13 bpm, P < 0.05). Similarly, the corrected QT interval from optimized extractions was significantly reduced (QTcB from 414 ± 32 to 402 ± 30 ms, P < 0.05). Using only baseline data, and after adjusting for intersubject variability, the standard deviation (SD) of QT intervals was highly reduced with optimized extraction (SD of QTcF from 11 ± 8 to 7 ± 2 ms, P < 0.05). Conclusions: Extraction of discrete 12-lead ECG strips from continuous Holter generates less noisy and more stable ECGs leading to more robust QTc data, thereby potentially facilitating the assessment of ECG effects on clinical trials. [source] Age differences in learning from text: Evidence for functionally distinct text processing systemsAPPLIED COGNITIVE PSYCHOLOGY, Issue 4 2009Matthew C. Shake We investigated the influence of sentence elaboration on self-regulated learning in order to examine age differences in resource allocation to the construction of textbase- and discourse-level representations. Older and younger adults learned about a topic by reading a series of sentences varying in elaboration (from simple factoids to highly elaborated text) and manner of presentation (progressive change in elaboration vs. random change in elaboration). Younger readers were more likely to recall information from factoids; older adults, from highly elaborated text. Relative to young, older readers showed an advantage in the progressive presentation condition, which minimised frequent changes between textbase- and discourse-level processing. Older adults showed poorer memory monitoring for factoids and less elaborated discourse relative to young, but when passages were highly elaborated or presented progressively, age differences were eliminated. Results support the idea that textbase- and discourse-level encoding arise from functionally distinct systems whose regulation depends on text properties and reader age. Copyright © 2008 John Wiley & Sons, Ltd. [source] Analytic and Heuristic Processing Influences on Adolescent Reasoning and Decision-MakingCHILD DEVELOPMENT, Issue 3 2001Paul A. Klaczynski The normative/descriptive gap is the discrepancy between actual reasoning and traditional standards for reasoning. The relationship between age and the normative/descriptive gap was examined by presenting adolescents with a battery of reasoning and decision-making tasks. Middle adolescents (N= 76) performed closer to normative ideals than early adolescents (N=66), although the normative/descriptive gap was large for both groups. Correlational analyses revealed that (1) normative responses correlated positively with each other, (2) nonnormative responses were positively interrelated, and (3) normative and nonnormative responses were largely independent. Factor analyses suggested that performance was based on two processing systems. The "analytic" system operates on "decontextualized" task representations and underlies conscious, computational reasoning. The "heuristic" system operates on "contextualized," content-laden representations and produces "cognitively cheap" responses that sometimes conflict with traditional norms. Analytic processing was more clearly linked to age and to intelligence than heuristic processing. Implications for cognitive development, the competence/performance issue, and rationality are discussed. [source] How Should a Speech Recognizer Work?COGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 6 2005Odette Scharenborg Abstract Although researchers studying human speech recognition (HSR) and automatic speech recognition (ASR) share a common interest in how information processing systems (human or machine) recognize spoken language, there is little communication between the two disciplines. We suggest that this lack of communication follows largely from the fact that research in these related fields has focused on the mechanics of how speech can be recognized. In Marr's (1982) terms, emphasis has been on the algorithmic and implementational levels rather than on the computational level. In this article, we provide a computational-level analysis of the task of speech recognition, which reveals the close parallels between research concerned with HSR and ASR. We illustrate this relation by presenting a new computational model of human spoken-word recognition, built using techniques from the field of ASR that, in contrast to current existing models of HSR, recognizes words from real speech input. [source] | |||||||||||||||||||||||||