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Sample records for normal learning rate

  1. Attentional Processing and Teacher Ratings in Hyperactive, Learning Disabled and Normal Boys.

    Science.gov (United States)

    Brown, Ronald T.; Wynne, Martha Ellen

    Sustained attention and inhibitory control of 15 nonhyperactive, learning disabled (LD) boys, 15 hyperactive but not LD boys, and 15 normal boys (11-12 years old) were studied, on teacher ratings of impulse control in the classroom and testing results. Coming to attention, decision making, sustained attention, and attention-concentration were…

  2. Rate of Visual Information Pick-Up in Learning Disabled and Normal Boys.

    Science.gov (United States)

    Bryant, Susan K.; And Others

    1983-01-01

    A span-of-apprehension task and a backward masking technique were combined to allow measurement of the apprehension span of a sample of 34 learning disabled and normal boys about 8 to 13 years old at various time intervals following stimulus presentation. (Author/SW)

  3. Classification of caesarean section and normal vaginal deliveries using foetal heart rate signals and advanced machine learning algorithms.

    Science.gov (United States)

    Fergus, Paul; Hussain, Abir; Al-Jumeily, Dhiya; Huang, De-Shuang; Bouguila, Nizar

    2017-07-06

    Visual inspection of cardiotocography traces by obstetricians and midwives is the gold standard for monitoring the wellbeing of the foetus during antenatal care. However, inter- and intra-observer variability is high with only a 30% positive predictive value for the classification of pathological outcomes. This has a significant negative impact on the perinatal foetus and often results in cardio-pulmonary arrest, brain and vital organ damage, cerebral palsy, hearing, visual and cognitive defects and in severe cases, death. This paper shows that using machine learning and foetal heart rate signals provides direct information about the foetal state and helps to filter the subjective opinions of medical practitioners when used as a decision support tool. The primary aim is to provide a proof-of-concept that demonstrates how machine learning can be used to objectively determine when medical intervention, such as caesarean section, is required and help avoid preventable perinatal deaths. This is evidenced using an open dataset that comprises 506 controls (normal virginal deliveries) and 46 cases (caesarean due to pH ≤ 7.20-acidosis, n = 18; pH > 7.20 and pH machine-learning algorithms are trained, and validated, using binary classifier performance measures. The findings show that deep learning classification achieves sensitivity = 94%, specificity = 91%, Area under the curve = 99%, F-score = 100%, and mean square error = 1%. The results demonstrate that machine learning significantly improves the efficiency for the detection of caesarean section and normal vaginal deliveries using foetal heart rate signals compared with obstetrician and midwife predictions and systems reported in previous studies.

  4. Exchange rate arrangements: From extreme to "normal"

    Directory of Open Access Journals (Sweden)

    Beker Emilija

    2006-01-01

    Full Text Available The paper studies theoretical and empirical location dispersion of exchange rate arrangements - rigid-intermediate-flexible regimes, in the context of extreme arrangements of a currency board, dollarization and monetary union moderate characteristics of intermediate arrangements (adjustable pegs crawling pegs and target zones and imperative-process "normalization" in the form of a managed or clean floating system. It is established that de iure and de facto classifications generate "fear of floating" and "fear of pegging". The "impossible trinity" under the conditions of capital liberalization and globalization creates a bipolar view or hypothesis of vanishing intermediate exchange rate regimes.

  5. Normalization and Personalization of Learning Situation: NPLS

    Directory of Open Access Journals (Sweden)

    Mounia Abik

    2009-06-01

    Full Text Available The personalization of learning is a major pedagogical challenge solicited by pedagogues and didacts. There are several projects about the production of personalizable learning situations such as Reload-LDE and Alfanet. These projects are interested in producing new standardized and personalizable learning situations. However, on the Web, an important number of learning situations exist. These situations are rich in information but don't consider all the characteristics of participants taking part in the learning, nor their technical environments. In this paper we suggest a help system that can transform an existing learning situation to another structure standardized and personalizable depending on the context of learning personalization that we have defined.

  6. An investigation on normal school students’ learning burnout – A case study of English normal students

    Directory of Open Access Journals (Sweden)

    Linjing Xu

    2017-11-01

    Full Text Available Learning burnout is a phenomenon in which students hold a negative attitude to curriculum learning, which manifests in aspects of physiology, psychology, behavior and interpersonal communication. China attaches great importance to higher education, colleges and universities shoulder the important task of training national modernization personnel. The problem of university students’ learning burnout has become a social phenomenon that cannot be ignored. Normal university students are one of the important groups of college students, and this phenomenon of learning burnout may also occur among them. English majors are the backbone of English teachers in primary and secondary schools in the future. The learning status of these groups affects the overall quality of teaching in normal colleges and universities and, more importantly, the quality of teachers in primary and secondary schools in the future. This paper first reviews the definition of learning burnout and the research methods of measurement. Subsequently, it investigates the learning burnout of English matriculation students by taking the first-year English majors of Jiangxi Normal University as an example. In this way, this research is hoped to promote the study on learning burnout not only among English normal students but also other normal students.

  7. Developing Visualization Support System for Teaching/Learning Database Normalization

    Science.gov (United States)

    Folorunso, Olusegun; Akinwale, AdioTaofeek

    2010-01-01

    Purpose: In tertiary institution, some students find it hard to learn database design theory, in particular, database normalization. The purpose of this paper is to develop a visualization tool to give students an interactive hands-on experience in database normalization process. Design/methodology/approach: The model-view-controller architecture…

  8. Optimized reaction mechanism rate rules for ignition of normal alkanes

    KAUST Repository

    Cai, Liming

    2016-08-11

    The increasing demand for cleaner combustion and reduced greenhouse gas emissions motivates research on the combustion of hydrocarbon fuels and their surrogates. Accurate detailed chemical kinetic models are an important prerequisite for high fidelity reacting flow simulations capable of improving combustor design and operation. The development of such models for many new fuel components and/or surrogate molecules is greatly facilitated by the application of reaction classes and rate rules. Accurate and versatile rate rules are desirable to improve the predictive accuracy of kinetic models. A major contribution in the literature is the recent work by Bugler et al. (2015), which has significantly improved rate rules and thermochemical parameters used in kinetic modeling of alkanes. In the present study, it is demonstrated that rate rules can be used and consistently optimized for a set of normal alkanes including n-heptane, n-octane, n-nonane, n-decane, and n-undecane, thereby improving the predictive accuracy for all the considered fuels. A Bayesian framework is applied in the calibration of the rate rules. The optimized rate rules are subsequently applied to generate a mechanism for n-dodecane, which was not part of the training set for the optimized rate rules. The developed mechanism shows accurate predictions compared with published well-validated mechanisms for a wide range of conditions.

  9. General anesthesia suppresses normal heart rate variability in humans

    Science.gov (United States)

    Matchett, Gerald; Wood, Philip

    2014-06-01

    The human heart normally exhibits robust beat-to-beat heart rate variability (HRV). The loss of this variability is associated with pathology, including disease states such as congestive heart failure (CHF). The effect of general anesthesia on intrinsic HRV is unknown. In this prospective, observational study we enrolled 100 human subjects having elective major surgical procedures under general anesthesia. We recorded continuous heart rate data via continuous electrocardiogram before, during, and after anesthesia, and we assessed HRV of the R-R intervals. We assessed HRV using several common metrics including Detrended Fluctuation Analysis (DFA), Multifractal Analysis, and Multiscale Entropy Analysis. Each of these analyses was done in each of the four clinical phases for each study subject over the course of 24 h: Before anesthesia, during anesthesia, early recovery, and late recovery. On average, we observed a loss of variability on the aforementioned metrics that appeared to correspond to the state of general anesthesia. Following the conclusion of anesthesia, most study subjects appeared to regain their normal HRV, although this did not occur immediately. The resumption of normal HRV was especially delayed on DFA. Qualitatively, the reduction in HRV under anesthesia appears similar to the reduction in HRV observed in CHF. These observations will need to be validated in future studies, and the broader clinical implications of these observations, if any, are unknown.

  10. Learning attention for historical text normalization by learning to pronounce

    DEFF Research Database (Denmark)

    Bollmann, Marcel; Bingel, Joachim; Søgaard, Anders

    2017-01-01

    Automated processing of historical texts often relies on pre-normalization to modern word forms. Training encoder-decoder architectures to solve such problems typically requires a lot of training data, which is not available for the named task. We address this problem by using several novel encoder...

  11. An Experiential Learning Activity Demonstrating Normal and Phobic Anxiety

    Science.gov (United States)

    Canu, Will H.

    2008-01-01

    This article describes an activity for an undergraduate abnormal psychology course that used student-generated data to illustrate normal versus clinically significant anxiety responses related to specific phobias. Students (N = 37) viewed 14 images of low- or high-anxiety valence and rated their subjective response to each. Discussion in a…

  12. The effect of normal aging and age-related macular degeneration on perceptual learning.

    Science.gov (United States)

    Astle, Andrew T; Blighe, Alan J; Webb, Ben S; McGraw, Paul V

    2015-01-01

    We investigated whether perceptual learning could be used to improve peripheral word identification speed. The relationship between the magnitude of learning and age was established in normal participants to determine whether perceptual learning effects are age invariant. We then investigated whether training could lead to improvements in patients with age-related macular degeneration (AMD). Twenty-eight participants with normal vision and five participants with AMD trained on a word identification task. They were required to identify three-letter words, presented 10° from fixation. To standardize crowding across each of the letters that made up the word, words were flanked laterally by randomly chosen letters. Word identification performance was measured psychophysically using a staircase procedure. Significant improvements in peripheral word identification speed were demonstrated following training (71% ± 18%). Initial task performance was correlated with age, with older participants having poorer performance. However, older adults learned more rapidly such that, following training, they reached the same level of performance as their younger counterparts. As a function of number of trials completed, patients with AMD learned at an equivalent rate as age-matched participants with normal vision. Improvements in word identification speed were maintained at least 6 months after training. We have demonstrated that temporal aspects of word recognition can be improved in peripheral vision with training across a range of ages and these learned improvements are relatively enduring. However, training targeted at other bottlenecks to peripheral reading ability, such as visual crowding, may need to be incorporated to optimize this approach.

  13. Speech Rate Normalization and Phonemic Boundary Perception in Cochlear-Implant Users

    Science.gov (United States)

    Jaekel, Brittany N.; Newman, Rochelle S.; Goupell, Matthew J.

    2017-01-01

    Purpose: Normal-hearing (NH) listeners rate normalize, temporarily remapping phonemic category boundaries to account for a talker's speech rate. It is unknown if adults who use auditory prostheses called cochlear implants (CI) can rate normalize, as CIs transmit degraded speech signals to the auditory nerve. Ineffective adjustment to rate…

  14. Rate-Agnostic (Causal) Structure Learning.

    Science.gov (United States)

    Plis, Sergey; Danks, David; Freeman, Cynthia; Calhoun, Vince

    2015-12-01

    Causal structure learning from time series data is a major scientific challenge. Extant algorithms assume that measurements occur sufficiently quickly; more precisely, they assume approximately equal system and measurement timescales. In many domains, however, measurements occur at a significantly slower rate than the underlying system changes, but the size of the timescale mismatch is often unknown. This paper develops three causal structure learning algorithms, each of which discovers all dynamic causal graphs that explain the observed measurement data, perhaps given undersampling. That is, these algorithms all learn causal structure in a "rate-agnostic" manner: they do not assume any particular relation between the measurement and system timescales. We apply these algorithms to data from simulations to gain insight into the challenge of undersampling.

  15. Speech rate normalization used to improve speaker verification

    CSIR Research Space (South Africa)

    Van Heerden, CJ

    2006-11-01

    Full Text Available the normalized durations is then compared with the EER using unnormalized durations, and also with the EER when duration information is not employed. 2. Proposed phoneme duration modeling 2.1. Choosing parametric models Since the duration of a phoneme... the known transcription and the speaker-specific acoustic model described above. Only one pronunciation per word was allowed, thus resulting in 49 triphones. To decide which parametric model to use for the duration density func- tions of the triphones...

  16. Optimized reaction mechanism rate rules for ignition of normal alkanes

    KAUST Repository

    Cai, Liming; Pitsch, Heinz; Mohamed, Samah; Raman, Venkat; Bugler, John; Curran, Henry; Sarathy, Mani

    2016-01-01

    fidelity reacting flow simulations capable of improving combustor design and operation. The development of such models for many new fuel components and/or surrogate molecules is greatly facilitated by the application of reaction classes and rate rules

  17. Constraining slip rates and spacings for active normal faults

    Science.gov (United States)

    Cowie, Patience A.; Roberts, Gerald P.

    2001-12-01

    Numerous observations of extensional provinces indicate that neighbouring faults commonly slip at different rates and, moreover, may be active over different time intervals. These published observations include variations in slip rate measured along-strike of a fault array or fault zone, as well as significant across-strike differences in the timing and rates of movement on faults that have a similar orientation with respect to the regional stress field. Here we review published examples from the western USA, the North Sea, and central Greece, and present new data from the Italian Apennines that support the idea that such variations are systematic and thus to some extent predictable. The basis for the prediction is that: (1) the way in which a fault grows is fundamentally controlled by the ratio of maximum displacement to length, and (2) the regional strain rate must remain approximately constant through time. We show how data on fault lengths and displacements can be used to model the observed patterns of long-term slip rate where measured values are sparse. Specifically, we estimate the magnitude of spatial variation in slip rate along-strike and relate it to the across-strike spacing between active faults.

  18. Early Embryonic Heart Rate in Normal Pregnancies In Memory of ...

    African Journals Online (AJOL)

    To determine the appearance and development of embryonic heart rate a total of n = 317 Nigerian pregnant women were studied in the very early pregnancy from 23 – 56 days from the onset of last menstrual period (LMP). All pregnancies had a subsequent successful outcome. Transvaginal ultrasonography was ...

  19. Automatic heart rate normalization for accurate energy expenditure normalization : an analysis of activities of daily living and heart rate features

    NARCIS (Netherlands)

    Altini, M.; Penders, J.; Vullers, R.J.M.; Amft, O.D.

    2014-01-01

    Introduction: This article is part of the Focus Theme of Methods of Information in Medicine on "Pervasive Intelligent Technologies for Health". Background: Energy Expenditure (EE) estimation algorithms using Heart Rate (HR) or a combination of accelerometer and HR data suffer from large error due to

  20. Out of sight, out of mind: Categorization learning and normal aging.

    Science.gov (United States)

    Schenk, Sabrina; Minda, John P; Lech, Robert K; Suchan, Boris

    2016-10-01

    The present combined EEG and eye tracking study examined the process of categorization learning at different age ranges and aimed to investigate to which degree categorization learning is mediated by visual attention and perceptual strategies. Seventeen young subjects and ten elderly subjects had to perform a visual categorization task with two abstract categories. Each category consisted of prototypical stimuli and an exception. The categorization of prototypical stimuli was learned very early during the experiment, while the learning of exceptions was delayed. The categorization of exceptions was accompanied by higher P150, P250 and P300 amplitudes. In contrast to younger subjects, elderly subjects had problems in the categorization of exceptions, but showed an intact categorization performance for prototypical stimuli. Moreover, elderly subjects showed higher fixation rates for important stimulus features and higher P150 amplitudes, which were positively correlated with the categorization performances. These results indicate that elderly subjects compensate for cognitive decline through enhanced perceptual and attentional processing of individual stimulus features. Additionally, a computational approach has been applied and showed a transition away from purely abstraction-based learning to an exemplar-based learning in the middle block for both groups. However, the calculated models provide a better fit for younger subjects than for elderly subjects. The current study demonstrates that human categorization learning is based on early abstraction-based processing followed by an exemplar-memorization stage. This strategy combination facilitates the learning of real world categories with a nuanced category structure. In addition, the present study suggests that categorization learning is affected by normal aging and modulated by perceptual processing and visual attention. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Impact of statistical learning methods on the predictive power of multivariate normal tissue complication probability models

    NARCIS (Netherlands)

    Xu, Cheng-Jian; van der Schaaf, Arjen; Schilstra, Cornelis; Langendijk, Johannes A.; van t Veld, Aart A.

    2012-01-01

    PURPOSE: To study the impact of different statistical learning methods on the prediction performance of multivariate normal tissue complication probability (NTCP) models. METHODS AND MATERIALS: In this study, three learning methods, stepwise selection, least absolute shrinkage and selection operator

  2. Subcategory learning in normal and language learning-disabled adults: how much information do they need?

    Science.gov (United States)

    Richardson, Jessica; Harris, Laurel; Plante, Elena; Gerken, Louann

    2006-12-01

    The purpose of this experiment was to determine if nonreferential morphophonological information was sufficient to facilitate the learning of gender subcategories (i.e., masculine vs. feminine) in individuals with normal language (NL) and those with a history of language-based learning disabilities (HLD). Thirty-two adults listened for 18 min to a familiarization set of Russian words that included either 1 (single-marked) or 2 (double-marked) morphophonological markers indicating gender. Participants were then tested on their knowledge of both trained and untrained members of each gender subcategory. Testing indicated that morphophonological information is sufficient for lexical subcategory learning in both NL and HLD groups, although the HLD group had lower overall accuracy. The HLD group benefited from double-marking relative to single-marking for subcategory learning. The results demonstrated that learning through implicit mechanisms occurred after a relatively brief exposure to the language stimuli. In addition, the weaker overall learning by the HLD group was facilitated when multiple cues to linguistic subcategory were available in the input group members received.

  3. Increased heart rate variability but normal resting metabolic rate in hypocretin/orexin-deficient human narcolepsy.

    NARCIS (Netherlands)

    Fronczek, R.; Overeem, S.; Reijntjes, R.; Lammers, G.J.; Dijk, J.G.M.; Pijl, H.

    2008-01-01

    STUDY OBJECTIVES: We investigated autonomic balance and resting metabolic rate to explore their possible involvement in obesity in hypocretin/orexin-deficient narcoleptic subjects. METHODS: Resting metabolic rate (using indirect calorimetry) and variability in heart rate and blood pressure were

  4. Conductive Hearing Loss in Autistic, Learning-Disabled, and Normal Children.

    Science.gov (United States)

    Smith, Donald E. P.; And Others

    1988-01-01

    Repeated impedance measures were given over five weeks to 11 autistic, 20 learning-disabled, and 20 normal children. A repeated measures analysis of variance led to the conclusion that fluctuating, negative middle ear pressure greater than normal characterizes both autistic and learning-disabled children with the more abnormal pressures typical in…

  5. Hemispherical dominance of glucose metabolic rate in the brain of the 'normal' ageing population

    NARCIS (Netherlands)

    Cutts, DA; Maguire, RP; Leenders, KL; Spyrou, NM

    2004-01-01

    In the 'normal' ageing brain a decrease in the cerebral metabolic rate has been determined across many brain regions. This study determines whether age differences would affect metabolic rates in regions and different hemispheres of the brain. The regional metabolic rate of glucose (rCMRGlu) was

  6. Normal brain activation in schizophrenia patients during associative emotional learning

    NARCIS (Netherlands)

    Swart, Marte; Liemburg, Edith Jantine; Kortekaas, Rudie; Wiersma, Durk; Bruggeman, Richard; Aleman, Andre

    2013-01-01

    Emotional deficits are among the core features of schizophrenia and both associative emotional learning and the related ability to verbalize emotions can be reduced. We investigated whether schizophrenia patients demonstrated impaired function of limbic and prefrontal areas during associative

  7. Heart rate variability in normal-weight patients with polycystic ovary syndrome

    OpenAIRE

    Kilit, Celal; Kilit, T?rkan Pa?al?

    2017-01-01

    Objective: Polycystic ovary syndrome (PCOS) is an endocrine disease closely related to several risk factors of cardiovascular disease. Obese women with PCOS show altered autonomic modulation. The results of studies investigating cardiac autonomic functions of normal-weight women with PCOS are conflicting. The aim of the study was to assess the reactivity of cardiac sympathovagal balance in normal-weight women with PCOS by heart rate variability analysis. Methods: We examined the heart rate va...

  8. Catecholaminergic Regulation of Learning Rate in a Dynamic Environment.

    Directory of Open Access Journals (Sweden)

    Marieke Jepma

    2016-10-01

    Full Text Available Adaptive behavior in a changing world requires flexibly adapting one's rate of learning to the rate of environmental change. Recent studies have examined the computational mechanisms by which various environmental factors determine the impact of new outcomes on existing beliefs (i.e., the 'learning rate'. However, the brain mechanisms, and in particular the neuromodulators, involved in this process are still largely unknown. The brain-wide neurophysiological effects of the catecholamines norepinephrine and dopamine on stimulus-evoked cortical responses suggest that the catecholamine systems are well positioned to regulate learning about environmental change, but more direct evidence for a role of this system is scant. Here, we report evidence from a study employing pharmacology, scalp electrophysiology and computational modeling (N = 32 that suggests an important role for catecholamines in learning rate regulation. We found that the P3 component of the EEG-an electrophysiological index of outcome-evoked phasic catecholamine release in the cortex-predicted learning rate, and formally mediated the effect of prediction-error magnitude on learning rate. P3 amplitude also mediated the effects of two computational variables-capturing the unexpectedness of an outcome and the uncertainty of a preexisting belief-on learning rate. Furthermore, a pharmacological manipulation of catecholamine activity affected learning rate following unanticipated task changes, in a way that depended on participants' baseline learning rate. Our findings provide converging evidence for a causal role of the human catecholamine systems in learning-rate regulation as a function of environmental change.

  9. Catecholaminergic Regulation of Learning Rate in a Dynamic Environment.

    Science.gov (United States)

    Jepma, Marieke; Murphy, Peter R; Nassar, Matthew R; Rangel-Gomez, Mauricio; Meeter, Martijn; Nieuwenhuis, Sander

    2016-10-01

    Adaptive behavior in a changing world requires flexibly adapting one's rate of learning to the rate of environmental change. Recent studies have examined the computational mechanisms by which various environmental factors determine the impact of new outcomes on existing beliefs (i.e., the 'learning rate'). However, the brain mechanisms, and in particular the neuromodulators, involved in this process are still largely unknown. The brain-wide neurophysiological effects of the catecholamines norepinephrine and dopamine on stimulus-evoked cortical responses suggest that the catecholamine systems are well positioned to regulate learning about environmental change, but more direct evidence for a role of this system is scant. Here, we report evidence from a study employing pharmacology, scalp electrophysiology and computational modeling (N = 32) that suggests an important role for catecholamines in learning rate regulation. We found that the P3 component of the EEG-an electrophysiological index of outcome-evoked phasic catecholamine release in the cortex-predicted learning rate, and formally mediated the effect of prediction-error magnitude on learning rate. P3 amplitude also mediated the effects of two computational variables-capturing the unexpectedness of an outcome and the uncertainty of a preexisting belief-on learning rate. Furthermore, a pharmacological manipulation of catecholamine activity affected learning rate following unanticipated task changes, in a way that depended on participants' baseline learning rate. Our findings provide converging evidence for a causal role of the human catecholamine systems in learning-rate regulation as a function of environmental change.

  10. Quantitative assessment of thallium myocardial washout rate: Importance of peak heart rate and lung thallium uptake in defining normal values

    International Nuclear Information System (INIS)

    Nishimura, Tsunehiko; Uehara, Toshiisa; Hayashida, Kohei; Kozuka, Takahiro; Saito, Muneyasu; Sumiyoshi, Tetsuya; National Cardiovascular Center, Suita, Osaka

    1987-01-01

    Traditionally, the results of exercise thallium scintigraphy were interpreted by transient defect analysis using initial and delayed images. Recently, washout rate analysis has been used for the relative quantification of exercise thallium scintigraphy. A diffuse slow washout from all myocardial regions has been defined as the indicator of extensive coronary artery disease. However, slow washout has occasionally been observed in normal cases and in healthy myocardial segments which are not supplied by a stenosed artery in patients with single or double vessel disease. We evaluate the factors influencing washout rate in 100 normal patients and 63 patients with angina pectoris (33 cases of single vessel disease and 30 cases of double vessel disease). The washout rates were calculated using circumferential profile analysis. In normal patients, washout rate was closely related to peak heart rate (r=0.72) and inversely related to lung thallium uptake (r=-0.56). A diffuse slow washout was observed in seven (7%) of 100 normal patients, six (18%) of 33 cases of single vessel disease and eight (24%) of 30 cases of double vessel disease. The patients with diffuse slow washout showed significantly higher lung thallium uptake values and lower peak heart rates than those without diffuse slow washout (P<0.01). Thus, this false positive slow washout should be considered in the interpretation of quantitative exercise thallium scintigraphy. (orig.)

  11. Music as a mnemonic to learn gesture sequences in normal aging and Alzheimer’s disease

    OpenAIRE

    Aline eMoussard; Emmanuel eBigand; Emmanuel eBigand; Isabelle ePeretz; Isabelle ePeretz; Isabelle ePeretz; Sylvie eBelleville; Sylvie eBelleville

    2014-01-01

    Strong links between music and motor functions suggest that music could represent an interesting aid for motor learning. The present study aims for the first time to test the potential of music to assist in the learning of sequences of gestures in normal and pathological aging. Participants with mild Alzheimer's disease (AD) and healthy older adults (Controls) learned sequences of meaningless gestures that were either accompanied by music or a metronome. We also manipulated the learning proce...

  12. Music as a Mnemonic to Learn Gesture Sequences in Normal Aging and Alzheimer’s Disease

    OpenAIRE

    Moussard, Aline; Bigand, Emmanuel; Belleville, Sylvie; Peretz, Isabelle

    2014-01-01

    Strong links between music and motor functions suggest that music could represent an interesting aid for motor learning. The present study aims for the first time to test the potential of music to assist in the learning of sequences of gestures in normal and pathological aging. Participants with mild Alzheimer’s disease (AD) and healthy older adults (controls) learned sequences of meaningless gestures that were either accompanied by music or a metronome. We also manipulated the learning proce...

  13. Written Narratives of Normal and Learning Disabled Children.

    Science.gov (United States)

    Johnson, Doris J.; Grant, James O.

    1989-01-01

    Writing samples of 295 primary school children improved in productivity, syntax, and level of abstraction from grade one through three. The writing of learning-disabled children who were matched with average reading ability primary-school children indicated no significant differences in productivity, but problems in syntax (especially morphology),…

  14. Analysis of a Dynamic Viscoelastic Contact Problem with Normal Compliance, Normal Damped Response, and Nonmonotone Slip Rate Dependent Friction

    Directory of Open Access Journals (Sweden)

    Mikaël Barboteu

    2016-01-01

    Full Text Available We consider a mathematical model which describes the dynamic evolution of a viscoelastic body in frictional contact with an obstacle. The contact is modelled with a combination of a normal compliance and a normal damped response law associated with a slip rate-dependent version of Coulomb’s law of dry friction. We derive a variational formulation and an existence and uniqueness result of the weak solution of the problem is presented. Next, we introduce a fully discrete approximation of the variational problem based on a finite element method and on an implicit time integration scheme. We study this fully discrete approximation schemes and bound the errors of the approximate solutions. Under regularity assumptions imposed on the exact solution, optimal order error estimates are derived for the fully discrete solution. Finally, after recalling the solution of the frictional contact problem, some numerical simulations are provided in order to illustrate both the behavior of the solution related to the frictional contact conditions and the theoretical error estimate result.

  15. Comparability of Self-Concept among Learning Disabled, Normal, and Gifted Students.

    Science.gov (United States)

    Winne, Phillip H.; And Others

    1982-01-01

    Using 60 fourth- to seventh-grade learning disabled (LD), normal, and gifted students, the comparability of representations of self-concept across groups was analyzed for the Sears and Coopersmith inventories. (Author/SW)

  16. A comparison of chewing rate between overweight and normal BMI individuals.

    Science.gov (United States)

    White, Amy Kristin; Venn, Bernard; Lu, Louise Weiwei; Rush, Elaine; Gallo, Luigi Maria; Yong, Janet Lee Ching; Farella, Mauro

    2015-06-01

    Previous attempts to identify an 'obese eating style' have led to conflicting findings. This observational study compared the chewing features of overweight or obese young adults with those of normal range BMI. We hypothesised that chewing features are individual-specific and differ between participants of a normal BMI and high BMI. Fourteen overweight to obese participants (BMI≥25.0) were pairwise matched with 14 normal range BMI participants (18.5chewing episodes, including rate, duration, and power. Masticatory performance was assessed by a sieve test and was expressed as the percentage of particles ≤2mm after a standardised chewing test. Regardless of the meal, chewing rate was remarkably consistent among participants (ICC=0.89; 95% CI=0.79-0.94). Chewing rate did not differ between high and normal BMI participants (p>0.05), whereas chewing power was significantly higher in high BMI participants (pchewing characteristics were found between BMI groups. Participants chewed at similar rate in the natural environment (pizza) and in the laboratory (rice) setting (p>0.05). Masticatory performance did not differ significantly (p>0.05) between the high (55.9%) and normal (52.4%) BMI groups. Within the limitations of the present study, chewing characteristics appear to be individual-specific with wide variability. Overweight participants chew at a similar rate to control participants, albeit slightly stronger. Our preliminary findings need to be replicated in larger samples. Copyright © 2015. Published by Elsevier Inc.

  17. Heart rate variability in normal-weight patients with polycystic ovary syndrome.

    Science.gov (United States)

    Kilit, Celal; Paşalı Kilit, Türkan

    2017-05-01

    Polycystic ovary syndrome (PCOS) is an endocrine disease closely related to several risk factors of cardiovascular disease. Obese women with PCOS show altered autonomic modulation. The results of studies investigating cardiac autonomic functions of normal-weight women with PCOS are conflicting. The aim of the study was to assess the reactivity of cardiac sympathovagal balance in normal-weight women with PCOS by heart rate variability analysis. We examined the heart rate variability in 60 normal-weight women with PCOS and compared them with that in 60 age-matched healthy women having a similar metabolic profile. Time and frequency domain parameters of heart rate variability were analyzed based on 5-min-long continuous electrocardiography recordings for the following 3 periods: (1) during rest in supine position, (2) during controlled breathing, and (3) during isometric handgrip exercise. Time and frequency domain parameters of heart rate variability for the 3 periods assessed were similar in the two groups. Although modified Ferriman-Gallwey score and serum testosterone and luteinizing hormone levels were significantly higher in women with PCOS, homeostatic model assessment-insulin resistance (HOMA-IR) was not different the between the PCOS and control groups. There were no significant correlations between serum testosterone levels and heart rate variability parameters among the study population. The findings of this study suggest that the reactivity of cardiac sympathovagal balance is not altered in normal-weight women with PCOS having a normal HOMA-IR.

  18. Renewable electricity generation in India—A learning rate analysis

    International Nuclear Information System (INIS)

    Partridge, Ian

    2013-01-01

    The cost of electricity generation using renewable technologies is widely assumed to be higher than the cost for conventional generation technologies, but likely to fall with growing experience of the technologies concerned. This paper tests the second part of that statement using learning rate analysis, based on large samples of wind and small hydro projects in India, and projects likely changes in these costs through 2020. It is the first study of learning rates for renewable generation technologies in India, and only the second in any developing country—it provides valuable input to the development of Indian energy policy and will be relevant to policy makers in other developing countries. The paper considers some potential problems with learning rate analysis raised by Nordhaus (2009. The Perils of the Learning Model for Modeling Endogenous Technological Change. National Bureau of Economic Research Working Paper Series No. 14638). By taking account of these issues, it is possible both to improve the models used for making cost projections and to examine the potential impact of remaining forecasting problems. - Highlights: • The first learning rate analysis of wind generation costs in India. • Only the second learning rate analysis for wind in any developing country. • Reviews missing variable and related issues in learning rate analysis. • Finds a 17.7% learning rate for wind generation costs in India. • Finds no significant learning effect for small hydro

  19. Learning normalized inputs for iterative estimation in medical image segmentation.

    Science.gov (United States)

    Drozdzal, Michal; Chartrand, Gabriel; Vorontsov, Eugene; Shakeri, Mahsa; Di Jorio, Lisa; Tang, An; Romero, Adriana; Bengio, Yoshua; Pal, Chris; Kadoury, Samuel

    2018-02-01

    In this paper, we introduce a simple, yet powerful pipeline for medical image segmentation that combines Fully Convolutional Networks (FCNs) with Fully Convolutional Residual Networks (FC-ResNets). We propose and examine a design that takes particular advantage of recent advances in the understanding of both Convolutional Neural Networks as well as ResNets. Our approach focuses upon the importance of a trainable pre-processing when using FC-ResNets and we show that a low-capacity FCN model can serve as a pre-processor to normalize medical input data. In our image segmentation pipeline, we use FCNs to obtain normalized images, which are then iteratively refined by means of a FC-ResNet to generate a segmentation prediction. As in other fully convolutional approaches, our pipeline can be used off-the-shelf on different image modalities. We show that using this pipeline, we exhibit state-of-the-art performance on the challenging Electron Microscopy benchmark, when compared to other 2D methods. We improve segmentation results on CT images of liver lesions, when contrasting with standard FCN methods. Moreover, when applying our 2D pipeline on a challenging 3D MRI prostate segmentation challenge we reach results that are competitive even when compared to 3D methods. The obtained results illustrate the strong potential and versatility of the pipeline by achieving accurate segmentations on a variety of image modalities and different anatomical regions. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Catecholaminergic Regulation of Learning Rate in a Dynamic Environment

    NARCIS (Netherlands)

    Jepma, Marieke; Murphy, Peter R.; Nassar, Matthew R.; Rangel-Gomez, Mauricio; Meeter, Martijn; Nieuwenhuis, Sander

    2016-01-01

    Adaptive behavior in a changing world requires flexibly adapting one’s rate of learning to the rate of environmental change. Recent studies have examined the computational mechanisms by which various environmental factors determine the impact of new outcomes on existing beliefs (i.e., the ‘learning

  1. Dose rate effect of 125I irradiation on normal rabbit eyes and experimental choroidal melanoma

    International Nuclear Information System (INIS)

    Yang, C.M.; Olsen, K.R.; Schwade, J.G.; Houdek, P.V.; Markoe, A.M.; Pisciotta, V.; Xiaodong Wu

    1993-01-01

    The dose rate effect of radiation by 125 I plaque on choroidal melanoma and normal intraocular tissue was studied. In the first part of the experiment, high activity plaques (HAP) and low activity plagues (LAP) were implanted on rabbit eyes with experimental Greene choroidal melanoma to deliver a total dose of 10 000 cGy to the tumor apex. The mean dose rate calculated at 0.5 mm from the inner sclera in eight eyes with high activity plaques was 3341.5 cGy hr -1 while that in ten eyes with low activity plaques was 239.9 cGy hr -1 . For tumors less than 1.0 mm in height, both groups showed complete tumor regression at the tumor implantation site after plaque treatment. For tumours more than 1.0 mm in height, two out of two eyes in the low activity plaque group and one of four eyes in the high activity plaque group failed to show complete tumor regression. In the second part of the experiment, 125 I plaques were implanted on the sclera of 12 normal rabbits' eyes. Six received high dose rate plaque treatment, while the other six received low dose rate plaque treatment. Clinical and histologic examinations demonstrated more damaging effects to the normal chorioretinal tissues at the plaque implantation site in the high dose rate plaque group. These results suggest that high dose rate plaques are more effective than low dose rate plaques when tumor height is statistically controlled. (Author)

  2. Chromosomal Aberrations in Normal and AT Cells Exposed to High Dose of Low Dose Rate Irradiation

    Science.gov (United States)

    Kawata, T.; Shigematsu, N.; Kawaguchi, O.; Liu, C.; Furusawa, Y.; Hirayama, R.; George, K.; Cucinotta, F.

    2011-01-01

    Ataxia telangiectasia (A-T) is a human autosomally recessive syndrome characterized by cerebellar ataxia, telangiectases, immune dysfunction, and genomic instability, and high rate of cancer incidence. A-T cell lines are abnormally sensitive to agents that induce DNA double strand breaks, including ionizing radiation. The diverse clinical features in individuals affected by A-T and the complex cellular phenotypes are all linked to the functional inactivation of a single gene (AT mutated). It is well known that cells deficient in ATM show increased yields of both simple and complex chromosomal aberrations after high-dose-rate irradiation, but, less is known on how cells respond to low-dose-rate irradiation. It has been shown that AT cells contain a large number of unrejoined breaks after both low-dose-rate irradiation and high-dose-rate irradiation, however sensitivity for chromosomal aberrations at low-dose-rate are less often studied. To study how AT cells respond to low-dose-rate irradiation, we exposed confluent normal and AT fibroblast cells to up to 3 Gy of gamma-irradiation at a dose rate of 0.5 Gy/day and analyzed chromosomal aberrations in G0 using fusion PCC (Premature Chromosomal Condensation) technique. Giemsa staining showed that 1 Gy induces around 0.36 unrejoined fragments per cell in normal cells and around 1.35 fragments in AT cells, whereas 3Gy induces around 0.65 fragments in normal cells and around 3.3 fragments in AT cells. This result indicates that AT cells can rejoin breaks less effectively in G0 phase of the cell cycle? compared to normal cells. We also analyzed chromosomal exchanges in normal and AT cells after exposure to 3 Gy of low-dose-rate rays using a combination of G0 PCC and FISH techniques. Misrejoining was detected in the AT cells only? When cells irradiated with 3 Gy were subcultured and G2 chromosomal aberrations were analyzed using calyculin-A induced PCC technique, the yield of unrejoined breaks decreased in both normal and AT

  3. Adaptive Convergence Rates of a Dirichlet Process Mixture of Multivariate Normals

    OpenAIRE

    Tokdar, Surya T.

    2011-01-01

    It is shown that a simple Dirichlet process mixture of multivariate normals offers Bayesian density estimation with adaptive posterior convergence rates. Toward this, a novel sieve for non-parametric mixture densities is explored, and its rate adaptability to various smoothness classes of densities in arbitrary dimension is demonstrated. This sieve construction is expected to offer a substantial technical advancement in studying Bayesian non-parametric mixture models based on stick-breaking p...

  4. Major floods, poor land use delay return of sedimentation to normal rates

    Science.gov (United States)

    Henry W. Anderson

    1972-01-01

    Recovery from flood-accelerated sedimentation affects both estimates of long-term average deposition and short-term monitoring of changes. "Years to return to normal" for 10 watersheds in northern California after a major flood accelerated sediment concentrations were analyzed. Returns to normalcy took from 0 to 9 years; rate of decline was related to both...

  5. Acoustic properties of naturally produced clear speech at normal speaking rates

    Science.gov (United States)

    Krause, Jean C.; Braida, Louis D.

    2004-01-01

    Sentences spoken ``clearly'' are significantly more intelligible than those spoken ``conversationally'' for hearing-impaired listeners in a variety of backgrounds [Picheny et al., J. Speech Hear. Res. 28, 96-103 (1985); Uchanski et al., ibid. 39, 494-509 (1996); Payton et al., J. Acoust. Soc. Am. 95, 1581-1592 (1994)]. While producing clear speech, however, talkers often reduce their speaking rate significantly [Picheny et al., J. Speech Hear. Res. 29, 434-446 (1986); Uchanski et al., ibid. 39, 494-509 (1996)]. Yet speaking slowly is not solely responsible for the intelligibility benefit of clear speech (over conversational speech), since a recent study [Krause and Braida, J. Acoust. Soc. Am. 112, 2165-2172 (2002)] showed that talkers can produce clear speech at normal rates with training. This finding suggests that clear speech has inherent acoustic properties, independent of rate, that contribute to improved intelligibility. Identifying these acoustic properties could lead to improved signal processing schemes for hearing aids. To gain insight into these acoustical properties, conversational and clear speech produced at normal speaking rates were analyzed at three levels of detail (global, phonological, and phonetic). Although results suggest that talkers may have employed different strategies to achieve clear speech at normal rates, two global-level properties were identified that appear likely to be linked to the improvements in intelligibility provided by clear/normal speech: increased energy in the 1000-3000-Hz range of long-term spectra and increased modulation depth of low frequency modulations of the intensity envelope. Other phonological and phonetic differences associated with clear/normal speech include changes in (1) frequency of stop burst releases, (2) VOT of word-initial voiceless stop consonants, and (3) short-term vowel spectra.

  6. On the asymptotic improvement of supervised learning by utilizing additional unlabeled samples - Normal mixture density case

    Science.gov (United States)

    Shahshahani, Behzad M.; Landgrebe, David A.

    1992-01-01

    The effect of additional unlabeled samples in improving the supervised learning process is studied in this paper. Three learning processes. supervised, unsupervised, and combined supervised-unsupervised, are compared by studying the asymptotic behavior of the estimates obtained under each process. Upper and lower bounds on the asymptotic covariance matrices are derived. It is shown that under a normal mixture density assumption for the probability density function of the feature space, the combined supervised-unsupervised learning is always superior to the supervised learning in achieving better estimates. Experimental results are provided to verify the theoretical concepts.

  7. The Effects of a Normal Rate versus a Slow Intervalled Rate of Oral Nutrient Intake and Intravenous Low Rate Macronutrient Application on Psychophysical Function – Two Pilot Studies

    Directory of Open Access Journals (Sweden)

    Melanie Y. Denzer-Lippmann

    2017-06-01

    Full Text Available Stomach distension and energy per time are factors influencing satiety. Moreover, different rates of nutrient intake induce different stomach distension. The goal of our studies was to elucidate the influence of different oral rates of nutrient intake (normal rate versus slow intervalled rate; study I and intravenous low rate macronutrient application (protein, carbohydrate, fat or placebo (study II on psychophysical function. The pilot studies investigated the effects of 1 study I: a mixed nutrient solution (1/3 protein, 1/3 fat, 1/3 carbohydrates 2 study II: intravenous macronutrient infusions (protein, carbohydrate, fat or placebo on psychophysical function (mood, hunger, food craving, alertness, smell intensity ratings and hedonic ratings in human subjects. In study I 10 male subjects (age range: 21–30 years completed the study protocol participating in both test conditions and in study II 20 male subjects (age range: 19–41 years completed the study protocol participating in all test conditions. Additionally, metabolic function was analyzed and cognitive and olfactory tests were conducted twice starting 100 min before the beginning of the intervention and 240 min after. Psychophysical (mood, hunger, fat-, protein-, carbohydrate-, sweets- and vegetable-craving, alertness and metabolic function tests were performed seven times on each examination day. Greater effects on hunger and food cravings were observed for normal rate of intake compared to slow intervalled rate of intake and intravenous low rate macronutrient application. Our findings potentially confirm that volume of the food ingested and a higher rate of energy per time contribute to satiety during normal rate of food intake, while slow intervalled rate of food intake and intravenous low rate macronutrient application showed no effects on satiation. Our results motivate the view that a certain amount of volume of the food ingested and a certain energy per time ratio are necessary

  8. Determinants of global left ventricular peak diastolic filling rate during rest and exercise in normal volunteers

    International Nuclear Information System (INIS)

    Filiberti, A.W.; Bianco, J.A.; Baker, S.P.; Doherty; Nalivaika, L.A.; King, M.A.; Alpert, J.S.

    1984-01-01

    Early peak diastolic filling rate (PFR) of the left ventricle (LV) is said to be a sensitive index of LV dysfunction in patients with coronary disease, hypertension and hypertrophic cardiomyopathy. Radionuclide (RN0 multigated PFR was measured in 20 normal volunteers (13 males, 7 females, mean age 31 yrs., range 20-43) at rest and during supine bicycle exercise conducted to a symptomatic end-point. At rest, RN PFR was 3.4 +- SD 0.4 end-diastolic vols./sec (range 3.1 - 3.6). During exercise all normal volunteers had a progressive and numerically and statistically significant increase in PFR. Stepwise multiple linear regression (BMPD2R) was applied to the rest and exercise PFR data to develop a linear model describing the main determinants of the RN PFR. The potential independent variables which were included in the model were heart rate (HR), ejection fraction (EF), systolic arterial pressure, systolic ejection rate and exercise stage. Ranking of variables for prediction of RN PFR, and exclusion of less important variables, was done by F value criteria. The final multivariate equation was: LVPFR = -3.84437 + 0.03834 HR + 0.07537 LVEF. The model fit was highly significant (p<0.001), and accounted for 89 per cent of variability in the PFR. The authors conclude that the left ventricular peak filling rate is critically determined by heart rate and by ejection fraction at rest and during exercise

  9. Hemispherical dominance of glucose metabolic rate in the brain of the 'normal' ageing population

    International Nuclear Information System (INIS)

    Cutts, D.A.; Spyrou, N.M.

    2004-01-01

    In the 'normal' ageing brain a decrease in the cerebral metabolic rate has been determined across many brain regions. It is determined whether age differences would affect metabolic rates in regions and different hemispheres of the brain. The regional metabolic rate of glucose (rCMRGlu) was examined in a group of 72 subjects, ages 22 to 82 years, with 36 regions of interest chosen from both hemispheres of the cortex, midbrain and cerebellum. To determine metabolic rates the in-vivo technique of positron emission tomography (PET) was employed. Three age groups were chosen to compare hemispherical differences. In both young and intermediate age groups the left hemisphere had higher rCMRGlu values than those of the right for the majority of regions with, although less pronounced in the intermediate group. Importantly, the older age group displayed little difference between hemispheres. (author)

  10. Using wavelength-normalized optical spectroscopy to improve the accuracy of bacteria growth rate quantification

    Science.gov (United States)

    McBirney, Samantha E.; Trinh, Kristy; Wong-Beringer, Annie; Armani, Andrea M.

    2017-02-01

    One of the fundamental analytical measurements performed in microbiology is monitoring and characterizing cell concentration in culture media. Measurement error will give rise to reproducibility problems in a wide range of applications, from biomanufacturing to basic research. Therefore, it is critical that the generated results are consistent. Single wavelength optical density (OD) measurements have become the preferred approach. Here, we compare the conventional OD600 technique with a multi-wavelength normalized scattering optical spectroscopy method to measure the growth rates of Pseudomonas aeruginosa and Staphylococcus aureus, two of the leading nosocomial pathogens with proven abilities to develop resistance. The multi-wavelength normalization process minimizes the impact of bacteria byproducts and environmental noise on the signal, thereby accurately quantifying growth rates with high fidelity at low concentrations. In contrast, due to poor absorbance and scattering at 600 nm, the classic OD600 measurement method is able to detect bacteria but cannot quantify the growth rate reliably. Our wavelength-normalization protocol to detect bacteria growth rates can be readily and easily adopted by research labs, given that it only requires the use of a standard spectrophotometer and implementation of straightforward data analysis. Measuring and monitoring bacteria growth rates play a critical role in a wide range of settings, spanning from therapeutic design and development to diagnostics and disease prevention. Having a full understanding of the growth cycles of bacteria known to cause severe infections and diseases will lead to a better understanding of the pathogenesis of these illnesses, leading to better treatment and, ultimately, the development of a cure.

  11. Event-Related EEG Oscillations to Semantically Unrelated Words in Normal and Learning Disabled Children

    Science.gov (United States)

    Fernandez, Thalia; Harmony, Thalia; Mendoza, Omar; Lopez-Alanis, Paula; Marroquin, Jose Luis; Otero, Gloria; Ricardo-Garcell, Josefina

    2012-01-01

    Learning disabilities (LD) are one of the most frequent problems for elementary school-aged children. In this paper, event-related EEG oscillations to semantically related and unrelated pairs of words were studied in a group of 18 children with LD not otherwise specified (LD-NOS) and in 16 children with normal academic achievement. We propose that…

  12. The Interpersonal Values of Parents of Normal and Learning Disabled Children.

    Science.gov (United States)

    Miletic, Anne

    1986-01-01

    L. Gordon's Survey of Interpersonal Values was used to compare 136 parents of normal and learning disabled children. Fathers of LD boys scored higher on Independence and Leadership and lower on Conformity and Support. Mothers of LD boys favored authoritative attitudes; same-sexed experimental mothers valued conformity and sources of emotional and…

  13. Category Specificity in Normal Episodic Learning: Applications to Object Recognition and Category-Specific Agnosia

    Science.gov (United States)

    Bukach, Cindy M.; Bub, Daniel N.; Masson, Michael E. J.; Lindsay, D. Stephen

    2004-01-01

    Studies of patients with category-specific agnosia (CSA) have given rise to multiple theories of object recognition, most of which assume the existence of a stable, abstract semantic memory system. We applied an episodic view of memory to questions raised by CSA in a series of studies examining normal observers' recall of newly learned attributes…

  14. Convergence analysis of Chauvin's PCA learning algorithm with a constant learning rate

    International Nuclear Information System (INIS)

    Lv Jiancheng; Yi Zhang

    2007-01-01

    The convergence of Chauvin's PCA learning algorithm with a constant learning rate is studied in this paper by using a DDT method (deterministic discrete-time system method). Different from the DCT method (deterministic continuous-time system method), the DDT method does not require that the learning rate converges to zero. An invariant set of Chauvin's algorithm with a constant learning rate is obtained so that the non-divergence of this algorithm can be guaranteed. Rigorous mathematic proofs are provided to prove the local convergence of this algorithm

  15. Convergence analysis of Chauvin's PCA learning algorithm with a constant learning rate

    Energy Technology Data Exchange (ETDEWEB)

    Lv Jiancheng [Computational Intelligence Laboratory, School of Computer Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054 (China); Yi Zhang [Computational Intelligence Laboratory, School of Computer Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054 (China)]. E-mail: zhangyi@uestc.edu.cn

    2007-05-15

    The convergence of Chauvin's PCA learning algorithm with a constant learning rate is studied in this paper by using a DDT method (deterministic discrete-time system method). Different from the DCT method (deterministic continuous-time system method), the DDT method does not require that the learning rate converges to zero. An invariant set of Chauvin's algorithm with a constant learning rate is obtained so that the non-divergence of this algorithm can be guaranteed. Rigorous mathematic proofs are provided to prove the local convergence of this algorithm.

  16. Reducing Error Rates for Iris Image using higher Contrast in Normalization process

    Science.gov (United States)

    Aminu Ghali, Abdulrahman; Jamel, Sapiee; Abubakar Pindar, Zahraddeen; Hasssan Disina, Abdulkadir; Mat Daris, Mustafa

    2017-08-01

    Iris recognition system is the most secured, and faster means of identification and authentication. However, iris recognition system suffers a setback from blurring, low contrast and illumination due to low quality image which compromises the accuracy of the system. The acceptance or rejection rates of verified user depend solely on the quality of the image. In many cases, iris recognition system with low image contrast could falsely accept or reject user. Therefore this paper adopts Histogram Equalization Technique to address the problem of False Rejection Rate (FRR) and False Acceptance Rate (FAR) by enhancing the contrast of the iris image. A histogram equalization technique enhances the image quality and neutralizes the low contrast of the image at normalization stage. The experimental result shows that Histogram Equalization Technique has reduced FRR and FAR compared to the existing techniques.

  17. Compression-rate-dependent nonlinear mechanics of normal and impaired porcine knee joints.

    Science.gov (United States)

    Rodriguez, Marcel Leonardo; Li, LePing

    2017-11-14

    The knee joint performs mechanical functions with various loading and unloading processes. Past studies have focused on the kinematics and elastic response of the joint with less understanding of the rate-dependent load response associated with viscoelastic and poromechanical behaviors. Forty-five fresh porcine knee joints were used in the present study to determine the loading-rate-dependent force-compression relationship, creep and relaxation of normal, dehydrated and meniscectomized joints. The mechanical tests of all normal intact joints showed similar strong compression-rate-dependent behavior: for a given compression-magnitude up to 1.2 mm, the reaction force varied 6 times over compression rates. While the static response was essentially linear, the nonlinear behavior was boosted with the increased compression rate to approach the asymptote or limit at approximately 2 mm/s. On the other hand, the joint stiffness varied approximately 3 times over different joints, when accounting for the maturity and breed of the animals. Both a loss of joint hydration and a total meniscectomy greatly compromised the load support in the joint, resulting in a reduction of load support as much as 60% from the corresponding intact joint. However, the former only weakened the transient load support, but the latter also greatly weakened the equilibrium load support. A total meniscectomy did not diminish the compression-rate-dependence of the joint though. These findings are consistent with the fluid-pressurization loading mechanism, which may have a significant implication in the joint mechanical function and cartilage mechanobiology.

  18. Influence of peak exercise heart rate on normal thallium-201 myocardial clearance

    International Nuclear Information System (INIS)

    Kaul, S.; Chesler, D.A.; Pohost, G.M.; Strauss, H.W.; Okada, R.D.; Boucher, C.A.

    1986-01-01

    Measurement of myocardial clearance rates between initial and delayed images is a major justification for adding computer quantification to the interpretation of exercise 201 TI images. To clarify the range of normal thallium clearance and its relationship to the level of exercise achieved, exercise thallium images in 89 normal subjects were analyzed: 45 asymptomatic subjects with less than 1% probability of coronary artery disease (CAD) (Group I), and 44 patients with chest pain found to have no significant CAD on angiography (Group II). Mean initial regional thallium uptake was similar in the two groups, but myocardial thallium clearance (mean +/- 1 s.d.) was slower in Group II, expressed as a longer half-life in the myocardium (8.2 +/- 7.6 hr compared with 3.4 +/- 0.7 hr p less than 0.001). Analysis of variance using ten clinical and exercise variables as covariates showed that the slower clearance in Group II was related to a lower peak exercise heart rate (HR) (154 +/- 27 compared with 183 +/- 11, respectively, p less than 0.001). By linear regression analysis, a decrease in peak HR of 1 beat/min was associated with a slower thallium clearance (longer half-life) of 0.05 hr. Using this formula, the clearance value in each patient was then corrected for peak exercise heart rate by decreasing measured clearance by 0.05 hr multiplied by the amount peak exercise heart rate which was below 183 (the mean value in Group I). There were no differences in the corrected clearance between the two groups. We conclude that thallium myocardial clearance after exercise is related in part to factors other than the presence of CAD, being slower when peak exercise HR is lower. Therefore, thallium clearance rates alone uncorrected for peak exercise heart rate should be used with caution when diagnosing CAD

  19. A simple algebraic cancer equation: calculating how cancers may arise with normal mutation rates

    Directory of Open Access Journals (Sweden)

    Shibata Darryl

    2010-01-01

    Full Text Available Abstract Background The purpose of this article is to present a relatively easy to understand cancer model where transformation occurs when the first cell, among many at risk within a colon, accumulates a set of driver mutations. The analysis of this model yields a simple algebraic equation, which takes as inputs the number of stem cells, mutation and division rates, and the number of driver mutations, and makes predictions about cancer epidemiology. Methods The equation [p = 1 - (1 - (1 - (1 - udkNm ] calculates the probability of cancer (p and contains five parameters: the number of divisions (d, the number of stem cells (N × m, the number of critical rate-limiting pathway driver mutations (k, and the mutation rate (u. In this model progression to cancer "starts" at conception and mutations accumulate with cell division. Transformation occurs when a critical number of rate-limiting pathway mutations first accumulates within a single stem cell. Results When applied to several colorectal cancer data sets, parameter values consistent with crypt stem cell biology and normal mutation rates were able to match the increase in cancer with aging, and the mutation frequencies found in cancer genomes. The equation can help explain how cancer risks may vary with age, height, germline mutations, and aspirin use. APC mutations may shorten pathways to cancer by effectively increasing the numbers of stem cells at risk. Conclusions The equation illustrates that age-related increases in cancer frequencies may result from relatively normal division and mutation rates. Although this equation does not encompass all of the known complexity of cancer, it may be useful, especially in a teaching setting, to help illustrate relationships between small and large cancer features.

  20. Caffeine effects on learning, performance, and anxiety in normal school-age children.

    Science.gov (United States)

    Bernstein, G A; Carroll, M E; Crosby, R D; Perwien, A R; Go, F S; Benowitz, N L

    1994-01-01

    The purpose of this investigation was to study the acute effects of caffeine on learning, performance, and anxiety in normal prepubertal children. Twenty-one children were evaluated in a double-blind, placebo-controlled crossover design. Subjects were studied during four sessions, 1 week apart, under the following conditions: baseline, placebo, 2.5 mg/kg caffeine, and 5.0 mg/kg caffeine. Subjects were randomized to order of placebo and the two dosages of caffeine. Dependent measures included tests of attention, manual dexterity, short-term memory, and processing speed. Anxiety rating scales were also administered. Saliva samples were analyzed for caffeine levels. Caffeine improved performance on two of four measures of the Test of Variables of Attention and on a test of manual dexterity in the dominant hand. There was a trend toward increased current level of self-reported anxiety after caffeine on a visual analogue measure of anxiety. Children reported feeling significantly less "sluggish" after caffeine ingestion than after placebo ingestion. In a small sample size, there was indication that caffeine enhanced performance on a test of attention and on a motor task. Children also reported feeling less "sluggish" but somewhat more anxious. Because caffeine is so widely available and frequently consumed by children, these results are important and need replication.

  1. Intrinsic washout rates of thallium-201 in normal and ischemic myocardium after dipyridamole-induced vasodilation

    International Nuclear Information System (INIS)

    Beller, G.A.; Holzgrefe, H.H.; Watson, D.D.

    1985-01-01

    Infusion of dipyridamole has been suggested as an alternative to exercise stress for myocardial perfusion imaging for detection of ischemia, but the mechanism and significance of thallium-201 ( 201 Tl) redistribution after administration of dipyridamole are uncertain. If disparate intrinsic cellular efflux rates of 201 Tl from normal and relatively underperfused myocardium in response to dipyridamole-induced vasodilation were observed, this could explain delayed 201 Tl redistribution. We investigated the effect of an intravenous infusion of 0.15 mg/kg dipyridamole on the intrinsic myocardial washout rate of 201 Tl as measured with a gamma-detector probe after intracoronary injection (50 muCi) of the radionuclide in open-chested anesthetized dogs. In six normal dogs the t 1/2 for intrinsic 201 Tl washout from the myocardium was 89 +/- 11 min (SE) at control conditions and became more rapid at 59 +/- 10 min (p . .0001) after dipyridamole. This corresponded to a significant increase in microsphere-determined epicardial (0.95 +/- 0.11 to 2.23 +/- 0.46 ml/min/g; p . .01) and endocardial (0.86 +/- 0.10 to 1.53 +/- 0.27; p . .029) flows. In 12 dogs with a critical coronary stenosis, the 201 Tl intrinsic washout rate slowed from 70 +/- 5 to 104 +/- 6 min (p . .0001) after production of the stenosis and slowed even further to 169 +/- 21 min (p . .003) after dipyridamole

  2. Non-linear learning in online tutorial to enhance students’ knowledge on normal distribution application topic

    Science.gov (United States)

    Kartono; Suryadi, D.; Herman, T.

    2018-01-01

    This study aimed to analyze the enhancement of non-linear learning (NLL) in the online tutorial (OT) content to students’ knowledge of normal distribution application (KONDA). KONDA is a competence expected to be achieved after students studied the topic of normal distribution application in the course named Education Statistics. The analysis was performed by quasi-experiment study design. The subject of the study was divided into an experimental class that was given OT content in NLL model and a control class which was given OT content in conventional learning (CL) model. Data used in this study were the results of online objective tests to measure students’ statistical prior knowledge (SPK) and students’ pre- and post-test of KONDA. The statistical analysis test of a gain score of KONDA of students who had low and moderate SPK’s scores showed students’ KONDA who learn OT content with NLL model was better than students’ KONDA who learn OT content with CL model. Meanwhile, for students who had high SPK’s scores, the gain score of students who learn OT content with NLL model had relatively similar with the gain score of students who learn OT content with CL model. Based on those findings it could be concluded that the NLL model applied to OT content could enhance KONDA of students in low and moderate SPK’s levels. Extra and more challenging didactical situation was needed for students in high SPK’s level to achieve the significant gain score.

  3. L-Carnosine reduces telomere damage and shortening rate in cultured normal fibroblasts

    International Nuclear Information System (INIS)

    Shao Lan; Li Qinghuan; Tan Zheng

    2004-01-01

    Telomere is the repetitive DNA sequence at the end of chromosomes, which shortens progressively with cell division and limits the replicative potential of normal human somatic cells. L-Carnosine, a naturally occurring dipeptide, has been reported to delay the replicative senescence, and extend the lifespan of cultured human diploid fibroblasts. In this work, we studied the effect of carnosine on the telomeric DNA of cultured human fetal lung fibroblast cells. Cells continuously grown in 20 mM carnosine exhibited a slower telomere shortening rate and extended lifespan in population doublings. When kept in a long-term nonproliferating state, they accumulated much less damages in the telomeric DNA when cultured in the presence of carnosine. We suggest that the reduction in telomere shortening rate and damages in telomeric DNA made an important contribution to the life-extension effect of carnosine

  4. A globally convergent MC algorithm with an adaptive learning rate.

    Science.gov (United States)

    Peng, Dezhong; Yi, Zhang; Xiang, Yong; Zhang, Haixian

    2012-02-01

    This brief deals with the problem of minor component analysis (MCA). Artificial neural networks can be exploited to achieve the task of MCA. Recent research works show that convergence of neural networks based MCA algorithms can be guaranteed if the learning rates are less than certain thresholds. However, the computation of these thresholds needs information about the eigenvalues of the autocorrelation matrix of data set, which is unavailable in online extraction of minor component from input data stream. In this correspondence, we introduce an adaptive learning rate into the OJAn MCA algorithm, such that its convergence condition does not depend on any unobtainable information, and can be easily satisfied in practical applications.

  5. Quantification of pulmonary thallium-201 activity after upright exercise in normal persons: importance of peak heart rate and propranolol usage in defining normal values

    International Nuclear Information System (INIS)

    Brown, K.A.; Boucher, C.A.; Okada, R.D.; Strauss, H.W.; Pohost, G.M.

    1984-01-01

    Fifty-nine normal patients (34 angiographically normal and 25 clinically normal by Bayesian analysis) underwent thallium-201 imaging after maximal upright exercise. Lung activity was quantitated relative to myocardial activity and a lung/myocardial activity ratio was determined for each patient. Stepwise regression analysis was then used to examine the influence of patient clinical characteristics and exercise variables on the lung/myocardium ratio. Peak heart rate during exercise and propranolol usage both showed significant negative regression coefficients (p less than 0.001). No other patient data showed a significant relation. Using the regression equation and the estimated variance, a 95% confidence level upper limit of normal could be determined for a give peak heart rate and propranolol status. Sixty-one other patients were studied to validate the predicted upper limits of normal based on this model. None of the 27 patients without coronary artery disease had an elevated lung/myocardial ratio, compared with 1 of 8 with 1-vessel disease (difference not significant), 6 of 14 with 2-vessel disease (p less than 0.005), and 6 of 12 with 3-vessel disease (p less than 0.0001). Thus, lung activity on upright exercise thallium-201 studies can be quantitated relative to myocardial activity, and is inversely related to peak heart rate and propranolol use. Use of a regression analysis allows determination of a 95% confidence upper limit of normal to be anticipated in an individual patient

  6. A review of learning rates for electricity supply technologies

    International Nuclear Information System (INIS)

    Rubin, Edward S.; Azevedo, Inês M.L.; Jaramillo, Paulina; Yeh, Sonia

    2015-01-01

    A variety of mathematical models have been proposed to characterize and quantify the dependency of electricity supply technology costs on various drivers of technological change. The most prevalent model form, called a learning curve, or experience curve, is a log-linear equation relating the unit cost of a technology to its cumulative installed capacity or electricity generated. This one-factor model is also the most common method used to represent endogenous technical change in large-scale energy-economic models that inform energy planning and policy analysis. A characteristic parameter is the “learning rate,” defined as the fractional reduction in cost for each doubling of cumulative production or capacity. In this paper, a literature review of the learning rates reported for 11 power generation technologies employing an array of fossil fuels, nuclear, and renewable energy sources is presented. The review also includes multi-factor models proposed for some energy technologies, especially two-factor models relating cost to cumulative expenditures for research and development (R&D) as well as the cumulative installed capacity or electricity production of a technology. For all technologies studied, we found substantial variability (as much as an order of magnitude) in reported learning rates across different studies. Such variability is not readily explained by systematic differences in the time intervals, geographic regions, choice of independent variable, or other parameters of each study. This uncertainty in learning rates, together with other limitations of current learning curve formulations, suggests the need for much more careful and systematic examination of the influence of how different factors and assumptions affect policy-relevant outcomes related to the future choice and cost of electricity supply and other energy technologies. - Highlights: • We review models explaining the cost of 11 electricity supply technologies. • The most prevalent model

  7. Enabling an Integrated Rate-temporal Learning Scheme on Memristor

    Science.gov (United States)

    He, Wei; Huang, Kejie; Ning, Ning; Ramanathan, Kiruthika; Li, Guoqi; Jiang, Yu; Sze, Jiayin; Shi, Luping; Zhao, Rong; Pei, Jing

    2014-04-01

    Learning scheme is the key to the utilization of spike-based computation and the emulation of neural/synaptic behaviors toward realization of cognition. The biological observations reveal an integrated spike time- and spike rate-dependent plasticity as a function of presynaptic firing frequency. However, this integrated rate-temporal learning scheme has not been realized on any nano devices. In this paper, such scheme is successfully demonstrated on a memristor. Great robustness against the spiking rate fluctuation is achieved by waveform engineering with the aid of good analog properties exhibited by the iron oxide-based memristor. The spike-time-dependence plasticity (STDP) occurs at moderate presynaptic firing frequencies and spike-rate-dependence plasticity (SRDP) dominates other regions. This demonstration provides a novel approach in neural coding implementation, which facilitates the development of bio-inspired computing systems.

  8. Music as a mnemonic to learn gesture sequences in normal aging and Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    Aline eMoussard

    2014-05-01

    Full Text Available Strong links between music and motor functions suggest that music could represent an interesting aid for motor learning. The present study aims for the first time to test the potential of music to assist in the learning of sequences of gestures in normal and pathological aging. Participants with mild Alzheimer's disease (AD and healthy older adults (Controls learned sequences of meaningless gestures that were either accompanied by music or a metronome. We also manipulated the learning procedure such that participants had to imitate the gestures to-be-memorized in synchrony with the experimenter or after the experimenter during encoding. Results show different patterns of performance for the two groups. Overall, musical accompaniment had no impact on the Controls' performance, but improved those of AD participants. Conversely, synchronization of gestures during learning helped Controls but seemed to interfere with retention in AD. We discuss these findings regarding their relevance for a better understanding of auditory-motor memory, and we propose recommendations to maximize the mnemonic effect of music for motor sequence learning for dementia care.

  9. Music as a Mnemonic to Learn Gesture Sequences in Normal Aging and Alzheimer’s Disease

    Science.gov (United States)

    Moussard, Aline; Bigand, Emmanuel; Belleville, Sylvie; Peretz, Isabelle

    2014-01-01

    Strong links between music and motor functions suggest that music could represent an interesting aid for motor learning. The present study aims for the first time to test the potential of music to assist in the learning of sequences of gestures in normal and pathological aging. Participants with mild Alzheimer’s disease (AD) and healthy older adults (controls) learned sequences of meaningless gestures that were either accompanied by music or a metronome. We also manipulated the learning procedure such that participants had to imitate the gestures to-be-memorized in synchrony with the experimenter or after the experimenter during encoding. Results show different patterns of performance for the two groups. Overall, musical accompaniment had no impact on the controls’ performance but improved those of AD participants. Conversely, synchronization of gestures during learning helped controls but seemed to interfere with retention in AD. We discuss these findings regarding their relevance for a better understanding of auditory–motor memory, and we propose recommendations to maximize the mnemonic effect of music for motor sequence learning for dementia care. PMID:24860476

  10. Music as a mnemonic to learn gesture sequences in normal aging and Alzheimer's disease.

    Science.gov (United States)

    Moussard, Aline; Bigand, Emmanuel; Belleville, Sylvie; Peretz, Isabelle

    2014-01-01

    Strong links between music and motor functions suggest that music could represent an interesting aid for motor learning. The present study aims for the first time to test the potential of music to assist in the learning of sequences of gestures in normal and pathological aging. Participants with mild Alzheimer's disease (AD) and healthy older adults (controls) learned sequences of meaningless gestures that were either accompanied by music or a metronome. We also manipulated the learning procedure such that participants had to imitate the gestures to-be-memorized in synchrony with the experimenter or after the experimenter during encoding. Results show different patterns of performance for the two groups. Overall, musical accompaniment had no impact on the controls' performance but improved those of AD participants. Conversely, synchronization of gestures during learning helped controls but seemed to interfere with retention in AD. We discuss these findings regarding their relevance for a better understanding of auditory-motor memory, and we propose recommendations to maximize the mnemonic effect of music for motor sequence learning for dementia care.

  11. Learning sung lyrics aids retention in normal ageing and Alzheimer's disease.

    Science.gov (United States)

    Moussard, Aline; Bigand, Emmanuel; Belleville, Sylvie; Peretz, Isabelle

    2014-01-01

    Previous studies have suggested that presenting to-be-memorised lyrics in a singing mode, instead of a speaking mode, may facilitate learning and retention in normal adults. In this study, seven healthy older adults and eight participants with mild Alzheimer's disease (AD) learned and memorised lyrics that were either sung or spoken. We measured the percentage of words recalled from these lyrics immediately and after 10 minutes. Moreover, in AD participants, we tested the effect of successive learning episodes for one spoken and one sung excerpt, as well as long-term retention after a four week delay. Sung conditions did not influence lyrics recall in immediate recall but increased delayed recall for both groups. In AD, learning slopes for sung and spoken lyrics did not show a significant difference across successive learning episodes. However, sung lyrics showed a slight advantage over spoken ones after a four week delay. These results suggest that singing may increase the load of initial learning but improve long-term retention of newly acquired verbal information. We further propose some recommendations on how to maximise these effects and make them relevant for therapeutic applications.

  12. Unravelling the Mysteries of Slip Histories, Validating Cosmogenic 36Cl Derived Slip Rates on Normal Faults

    Science.gov (United States)

    Goodall, H.; Gregory, L. C.; Wedmore, L.; Roberts, G.; Shanks, R. P.; McCaffrey, K. J. W.; Amey, R.; Hooper, A. J.

    2017-12-01

    The cosmogenic isotope chlorine-36 (36Cl) is increasingly used as a tool to investigate normal fault slip rates over the last 10-20 thousand years. These slip histories are being used to address complex questions, including investigating slip clustering and understanding local and large scale fault interaction. Measurements are time consuming and expensive, and as a result there has been little work done validating these 36Cl derived slip histories. This study aims to investigate if the results are repeatable and therefore reliable estimates of how normal faults have been moving in the past. Our approach is to test if slip histories derived from 36Cl are the same when measured at different points along the same fault. As normal fault planes are progressively exhumed from the surface they accumulate 36Cl. Modelling these 36Cl concentrations allows estimation of a slip history. In a previous study, samples were collected from four sites on the Magnola fault in the Italian Apennines. Remodelling of the 36Cl data using a Bayesian approach shows that the sites produced disparate slip histories, which we interpret as being due to variable site geomorphology. In this study, multiple sites have been sampled along the Campo Felice fault in the central Italian Apennines. Initial results show strong agreement between the sites we have processed so far and a previous study. This indicates that if sample sites are selected taking the geomorphology into account, then 36Cl derived slip histories will be highly similar when sampled at any point along the fault. Therefore our study suggests that 36Cl derived slip histories are a consistent record of fault activity in the past.

  13. The effect of learning models and emotional intelligence toward students learning outcomes on reaction rate

    Science.gov (United States)

    Sutiani, Ani; Silitonga, Mei Y.

    2017-08-01

    This research focused on the effect of learning models and emotional intelligence in students' chemistry learning outcomes on reaction rate teaching topic. In order to achieve the objectives of the research, with 2x2 factorial research design was used. There were two factors tested, namely: the learning models (factor A), and emotional intelligence (factor B) factors. Then, two learning models were used; problem-based learning/PBL (A1), and project-based learning/PjBL (A2). While, the emotional intelligence was divided into higher and lower types. The number of population was six classes containing 243 grade X students of SMAN 10 Medan, Indonesia. There were 15 students of each class were chosen as the sample of the research by applying purposive sampling technique. The data were analyzed by applying two-ways analysis of variance (2X2) at the level of significant α = 0.05. Based on hypothesis testing, there was the interaction between learning models and emotional intelligence in students' chemistry learning outcomes. Then, the finding of the research showed that students' learning outcomes in reaction rate taught by using PBL with higher emotional intelligence is higher than those who were taught by using PjBL. There was no significant effect between students with lower emotional intelligence taught by using both PBL and PjBL in reaction rate topic. Based on the finding, the students with lower emotional intelligence were quite hard to get in touch with other students in group discussion.

  14. Impact of Statistical Learning Methods on the Predictive Power of Multivariate Normal Tissue Complication Probability Models

    Energy Technology Data Exchange (ETDEWEB)

    Xu Chengjian, E-mail: c.j.xu@umcg.nl [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Schaaf, Arjen van der; Schilstra, Cornelis; Langendijk, Johannes A.; Veld, Aart A. van' t [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)

    2012-03-15

    Purpose: To study the impact of different statistical learning methods on the prediction performance of multivariate normal tissue complication probability (NTCP) models. Methods and Materials: In this study, three learning methods, stepwise selection, least absolute shrinkage and selection operator (LASSO), and Bayesian model averaging (BMA), were used to build NTCP models of xerostomia following radiotherapy treatment for head and neck cancer. Performance of each learning method was evaluated by a repeated cross-validation scheme in order to obtain a fair comparison among methods. Results: It was found that the LASSO and BMA methods produced models with significantly better predictive power than that of the stepwise selection method. Furthermore, the LASSO method yields an easily interpretable model as the stepwise method does, in contrast to the less intuitive BMA method. Conclusions: The commonly used stepwise selection method, which is simple to execute, may be insufficient for NTCP modeling. The LASSO method is recommended.

  15. Impact of statistical learning methods on the predictive power of multivariate normal tissue complication probability models.

    Science.gov (United States)

    Xu, Cheng-Jian; van der Schaaf, Arjen; Schilstra, Cornelis; Langendijk, Johannes A; van't Veld, Aart A

    2012-03-15

    To study the impact of different statistical learning methods on the prediction performance of multivariate normal tissue complication probability (NTCP) models. In this study, three learning methods, stepwise selection, least absolute shrinkage and selection operator (LASSO), and Bayesian model averaging (BMA), were used to build NTCP models of xerostomia following radiotherapy treatment for head and neck cancer. Performance of each learning method was evaluated by a repeated cross-validation scheme in order to obtain a fair comparison among methods. It was found that the LASSO and BMA methods produced models with significantly better predictive power than that of the stepwise selection method. Furthermore, the LASSO method yields an easily interpretable model as the stepwise method does, in contrast to the less intuitive BMA method. The commonly used stepwise selection method, which is simple to execute, may be insufficient for NTCP modeling. The LASSO method is recommended. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Impact of Statistical Learning Methods on the Predictive Power of Multivariate Normal Tissue Complication Probability Models

    International Nuclear Information System (INIS)

    Xu Chengjian; Schaaf, Arjen van der; Schilstra, Cornelis; Langendijk, Johannes A.; Veld, Aart A. van’t

    2012-01-01

    Purpose: To study the impact of different statistical learning methods on the prediction performance of multivariate normal tissue complication probability (NTCP) models. Methods and Materials: In this study, three learning methods, stepwise selection, least absolute shrinkage and selection operator (LASSO), and Bayesian model averaging (BMA), were used to build NTCP models of xerostomia following radiotherapy treatment for head and neck cancer. Performance of each learning method was evaluated by a repeated cross-validation scheme in order to obtain a fair comparison among methods. Results: It was found that the LASSO and BMA methods produced models with significantly better predictive power than that of the stepwise selection method. Furthermore, the LASSO method yields an easily interpretable model as the stepwise method does, in contrast to the less intuitive BMA method. Conclusions: The commonly used stepwise selection method, which is simple to execute, may be insufficient for NTCP modeling. The LASSO method is recommended.

  17. Blood pressure and heart rate variability analysis of orthostatic challenge in normal human pregnancies.

    Science.gov (United States)

    Heiskanen, Nonna; Saarelainen, Heli; Valtonen, Pirjo; Lyyra-Laitinen, Tiina; Laitinen, Tomi; Vanninen, Esko; Heinonen, Seppo

    2008-11-01

    The aim of the present study was to evaluate pregnancy-related changes in autonomic regulatory functions in healthy subjects. We studied cardiovascular autonomic responses to head-up tilt (HUT) in 28 pregnant women during the third trimester of pregnancy and 3 months after parturition. The maternal ECG and non-invasive beat-to-beat blood pressure were recorded in the horizontal position (left-lateral position) and during HUT in the upright position. Stroke volume was assessed from blood pressure signal by using the arterial pulse contour method. Heart rate variability (HRV) was analysed in frequency domain, and baroreflex sensitivity by the cross-spectral and the sequence methods. In the horizontal position, all frequency components of HRV were lower during pregnancy than 3 months after parturition (P pregnancy had no influence on normalized low frequency and high frequency powers. During pregnancy haemodynamics was well balanced with only minor changes in response to postural change while haemodynamic responses to HUT were more remarkable after parturition. In pregnant women HRV and especially its very low frequency component increased in response to HUT, whereas at 3 months after parturition the direction of these changes was opposite. Parasympathetic deactivation towards term is likely to contribute to increased heart rate and cardiac output at rest, whereas restored sympathetic modulation with modest responses may contribute stable peripheral resistance and sufficient placental blood supply under stimulated conditions. It is important to understand cardiovascular autonomic nervous system and haemodynamic control in normal pregnancy before being able to judge whether they are dysregulated in complicated pregnancies.

  18. Comparison of Child Abuse between Normal Children and Children with Learning Disorder

    Directory of Open Access Journals (Sweden)

    Narges Keshavarz-Valiyan

    2010-10-01

    Full Text Available Objective: The aim of this study was to compare child abuse between normal children and children with learning disorder, aged 7-12 in Tehran city. Materials & Methods: This analytical and cross sectional study is a research in causative-comparative method. 120 normal children of primary school from districts 3.7 and 15 of Tehran education and 120 children with learning disorder from three center of primary school students with learning disorder (1.2 and 3 were selected by multistage cluster sampaling method and evaluated by Reliable Child Abuse Questionnaire. Data were analyzed by Pearson correlation coefficient Friedman rank test and Paired T and independent T tests. Results: In children view, there were signifivant differences in mean scores of affective abuse (p<0.001 and total score of child abuse (p=0.002 between two groups. Likewise in parent's view. there were significant differences in mean scores of affective abuse (p<0.001, physical abuse (p<0.011 and total score of child abuse (p<0.001 between two groups. Also, there were significant differences between the ideas of children and their parents about physical abuse (p<0.002, sexual abuse (p<0.001 and ignorance (p<0.001 Conclusion: The tindings reveal that there is a difference between normal chidren and children with learning disorder in the extent of child abuse regarding it's type and in comparison with previous researches, affective abuse is more than other abuse types. So. it is necessary for mental health professionals to provide programs for training parents in future.

  19. Normal overall mortality rate in Addison's disease, but young patients are at risk of premature death.

    Science.gov (United States)

    Erichsen, Martina M; Løvås, Kristian; Fougner, Kristian J; Svartberg, Johan; Hauge, Erik R; Bollerslev, Jens; Berg, Jens P; Mella, Bjarne; Husebye, Eystein S

    2009-02-01

    Primary adrenal insufficiency (Addison's disease) is a rare autoimmune disease. Until recently, life expectancy in Addison's disease patients was considered normal. To determine the mortality rate in Addison's disease patients. i) Patients registered with Addison's disease in Norway during 1943-2005 were identified through search in hospital diagnosis registries. Scrutiny of the medical records provided diagnostic accuracy and age at diagnosis. ii) The patients who had died were identified from the National Directory of Residents. iii) Background mortality data were obtained from Statistics Norway, and standard mortality rate (SMR) calculated. iv) Death diagnoses were obtained from the Norwegian Death Cause Registry. Totally 811 patients with Addison's disease were identified, of whom 147 were deceased. Overall SMR was 1.15 (95% confidence intervals (CI) 0.96-1.35), similar in females (1.18 (0.92-1.44)) and males (1.10 (0.80-1.39)). Patients diagnosed before the age of 40 had significantly elevated SMR at 1.50 (95% CI 1.09-2.01), most pronounced in males (2.03 (1.19-2.86)). Acute adrenal failure was a major cause of death; infection and sudden death were more common than in the general population. The mean ages at death for females (75.7 years) and males (64.8 years) were 3.2 and 11.2 years less than the estimated life expectancy. Addison's disease is still a potentially lethal condition, with excess mortality in acute adrenal failure, infection, and sudden death in patients diagnosed at young age. Otherwise, the prognosis is excellent for patients with Addison's disease.

  20. The Normalized-Rate Iterative Algorithm: A Practical Dynamic Spectrum Management Method for DSL

    Directory of Open Access Journals (Sweden)

    Statovci Driton

    2006-01-01

    Full Text Available We present a practical solution for dynamic spectrum management (DSM in digital subscriber line systems: the normalized-rate iterative algorithm (NRIA. Supported by a novel optimization problem formulation, the NRIA is the only DSM algorithm that jointly addresses spectrum balancing for frequency division duplexing systems and power allocation for the users sharing a common cable bundle. With a focus on being implementable rather than obtaining the highest possible theoretical performance, the NRIA is designed to efficiently solve the DSM optimization problem with the operators' business models in mind. This is achieved with the help of two types of parameters: the desired network asymmetry and the desired user priorities. The NRIA is a centralized DSM algorithm based on the iterative water-filling algorithm (IWFA for finding efficient power allocations, but extends the IWFA by finding the achievable bitrates and by optimizing the bandplan. It is compared with three other DSM proposals: the IWFA, the optimal spectrum balancing algorithm (OSBA, and the bidirectional IWFA (bi-IWFA. We show that the NRIA achieves better bitrate performance than the IWFA and the bi-IWFA. It can even achieve performance almost as good as the OSBA, but with dramatically lower requirements on complexity. Additionally, the NRIA can achieve bitrate combinations that cannot be supported by any other DSM algorithm.

  1. The Normalized-Rate Iterative Algorithm: A Practical Dynamic Spectrum Management Method for DSL

    Science.gov (United States)

    Statovci, Driton; Nordström, Tomas; Nilsson, Rickard

    2006-12-01

    We present a practical solution for dynamic spectrum management (DSM) in digital subscriber line systems: the normalized-rate iterative algorithm (NRIA). Supported by a novel optimization problem formulation, the NRIA is the only DSM algorithm that jointly addresses spectrum balancing for frequency division duplexing systems and power allocation for the users sharing a common cable bundle. With a focus on being implementable rather than obtaining the highest possible theoretical performance, the NRIA is designed to efficiently solve the DSM optimization problem with the operators' business models in mind. This is achieved with the help of two types of parameters: the desired network asymmetry and the desired user priorities. The NRIA is a centralized DSM algorithm based on the iterative water-filling algorithm (IWFA) for finding efficient power allocations, but extends the IWFA by finding the achievable bitrates and by optimizing the bandplan. It is compared with three other DSM proposals: the IWFA, the optimal spectrum balancing algorithm (OSBA), and the bidirectional IWFA (bi-IWFA). We show that the NRIA achieves better bitrate performance than the IWFA and the bi-IWFA. It can even achieve performance almost as good as the OSBA, but with dramatically lower requirements on complexity. Additionally, the NRIA can achieve bitrate combinations that cannot be supported by any other DSM algorithm.

  2. Communication between hearing impaired and normal hearing students: a facilitative proposal of learning in higher education

    Directory of Open Access Journals (Sweden)

    Krysne Kelly de França Oliveira

    2014-09-01

    Full Text Available Introduction: There has been an increase in the number of hearing impaired people with access to higher education. Most of them are young people from a different culture who present difficulties in communication, inter-relationship, and learning in a culture of normal hearing people, because they use a different language, the Brazilian Sign Language - LIBRAS. Objective: The present study aimed to identify the forms of communication used between hearing impaired and normal hearing students, verifying how they can interfere with the learning process of the first. Methods: A qualitative study that used the space of a private university in the city of Fortaleza, Ceará state, Brazil, from February to April 2009. We carried out semi-structured interviews with three hearing impaired students, three teachers, three interpreters, and three normal hearing students. The content of the speeches was categorized and organized by the method of thematic analysis. Results: We verified that the forms of communication used ranged from mime and gestures to writing and drawing, but the most accepted by the hearing impaired students was LIBRAS. As a method of communication, it supports the learning of hearing impaired students, and with the mediation of interpreters, it gives them conditions to settle in their zones of development, according to the precepts of Vygotsky. Conclusion: Thus, we recognize the importance of LIBRAS as predominant language, essential to the full academic achievement of hearing impaired students; however, their efforts and dedication, as well as the interest of institutions and teachers on the deaf culture, are also important for preparing future professionals.

  3. Reduction in the retinotopic early visual cortex with normal aging and magnitude of perceptual learning.

    Science.gov (United States)

    Chang, Li-Hung; Yotsumoto, Yuko; Salat, David H; Andersen, George J; Watanabe, Takeo; Sasaki, Yuka

    2015-01-01

    Although normal aging is known to reduce cortical structures globally, the effects of aging on local structures and functions of early visual cortex are less understood. Here, using standard retinotopic mapping and magnetic resonance imaging morphologic analyses, we investigated whether aging affects areal size of the early visual cortex, which were retinotopically localized, and whether those morphologic measures were associated with individual performance on visual perceptual learning. First, significant age-associated reduction was found in the areal size of V1, V2, and V3. Second, individual ability of visual perceptual learning was significantly correlated with areal size of V3 in older adults. These results demonstrate that aging changes local structures of the early visual cortex, and the degree of change may be associated with individual visual plasticity. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Multi-center MRI carotid plaque component segmentation using feature normalization and transfer learning

    DEFF Research Database (Denmark)

    van Engelen, Arna; van Dijk, Anouk C; Truijman, Martine T.B.

    2015-01-01

    implementation of supervised methods. In this paper we segment carotid plaque components of clinical interest (fibrous tissue, lipid tissue, calcification and intraplaque hemorrhage) in a multicenter MRI study. We perform voxelwise tissue classification by traditional same-center training, and compare results...... not yield significant differences from that reference. We conclude that both extensive feature normalization and transfer learning can be valuable for the development of supervised methods that perform well on different types of datasets.......Automated segmentation of plaque components in carotid artery MRI is important to enable large studies on plaque vulnerability, and for incorporating plaque composition as an imaging biomarker in clinical practice. Especially supervised classification techniques, which learn from labeled examples...

  5. Parameters optimization for wavelet denoising based on normalized spectral angle and threshold constraint machine learning

    Science.gov (United States)

    Li, Hao; Ma, Yong; Liang, Kun; Tian, Yong; Wang, Rui

    2012-01-01

    Wavelet parameters (e.g., wavelet type, level of decomposition) affect the performance of the wavelet denoising algorithm in hyperspectral applications. Current studies select the best wavelet parameters for a single spectral curve by comparing similarity criteria such as spectral angle (SA). However, the method to find the best parameters for a spectral library that contains multiple spectra has not been studied. In this paper, a criterion named normalized spectral angle (NSA) is proposed. By comparing NSA, the best combination of parameters for a spectral library can be selected. Moreover, a fast algorithm based on threshold constraint and machine learning is developed to reduce the time of a full search. After several iterations of learning, the combination of parameters that constantly surpasses a threshold is selected. The experiments proved that by using the NSA criterion, the SA values decreased significantly, and the fast algorithm could save 80% time consumption, while the denoising performance was not obviously impaired.

  6. A combination of HARMONIE short time direct normal irradiance forecasts and machine learning: The #hashtdim procedure

    Science.gov (United States)

    Gastón, Martín; Fernández-Peruchena, Carlos; Körnich, Heiner; Landelius, Tomas

    2017-06-01

    The present work describes the first approach of a new procedure to forecast Direct Normal Irradiance (DNI): the #hashtdim that treats to combine ground information and Numerical Weather Predictions. The system is centered in generate predictions for the very short time. It combines the outputs from the Numerical Weather Prediction Model HARMONIE with an adaptive methodology based on Machine Learning. The DNI predictions are generated with 15-minute and hourly temporal resolutions and presents 3-hourly updates. Each update offers forecasts to the next 12 hours, the first nine hours are generated with 15-minute temporal resolution meanwhile the last three hours present hourly temporal resolution. The system is proved over a Spanish emplacement with BSRN operative station in south of Spain (PSA station). The #hashtdim has been implemented in the framework of the Direct Normal Irradiance Nowcasting methods for optimized operation of concentrating solar technologies (DNICast) project, under the European Union's Seventh Programme for research, technological development and demonstration framework.

  7. Reconstruction of normal forms by learning informed observation geometries from data.

    Science.gov (United States)

    Yair, Or; Talmon, Ronen; Coifman, Ronald R; Kevrekidis, Ioannis G

    2017-09-19

    The discovery of physical laws consistent with empirical observations is at the heart of (applied) science and engineering. These laws typically take the form of nonlinear differential equations depending on parameters; dynamical systems theory provides, through the appropriate normal forms, an "intrinsic" prototypical characterization of the types of dynamical regimes accessible to a given model. Using an implementation of data-informed geometry learning, we directly reconstruct the relevant "normal forms": a quantitative mapping from empirical observations to prototypical realizations of the underlying dynamics. Interestingly, the state variables and the parameters of these realizations are inferred from the empirical observations; without prior knowledge or understanding, they parametrize the dynamics intrinsically without explicit reference to fundamental physical quantities.

  8. Scaling of normalized mean energy and scalar dissipation rates in a turbulent channel flow

    Science.gov (United States)

    Abe, Hiroyuki; Antonia, Robert Anthony

    2011-05-01

    Non-dimensional parameters for the mean energy and scalar dissipation rates Cɛ and Cɛθ are examined using direct numerical simulation (DNS) data obtained in a fully developed turbulent channel flow with a passive scalar (Pr = 0.71) at several values of the Kármán (Reynolds) number h+. It is shown that Cɛ and Cɛθ are approximately equal in the near-equilibrium region (viz., y+ = 100 to y/h = 0.7) where the production and dissipation rates of either the turbulent kinetic energy or scalar variance are approximately equal and the magnitudes of the diffusion terms are negligibly small. The magnitudes of Cɛ and Cɛθ are about 2 and 1 in the logarithmic and outer regions, respectively, when h+ is sufficiently large. The former value is about the same for the channel, pipe, and turbulent boundary layer, reflecting the similarity between the mean velocity and temperature distributions among these three canonical flows. The latter value is, on the other hand, about twice as large as in homogeneous isotropic turbulence due to the existence of the large-scale u structures in the channel. The behaviour of Cɛ and Cɛθ impacts on turbulence modeling. In particular, the similarity between Cɛ and Cɛθ leads to a simple relation for the scalar variance to turbulent kinetic energy time-scale ratio, an important ingredient in the eddy diffusivity model. This similarity also yields a relation between the Taylor and Corrsin microscales and analogous relations, in terms of h+, for the Taylor microscale Reynolds number and Corrsin microscale Peclet number. This dependence is reasonably well supported by both the DNS data at small to moderate h+ and the experimental data of Comte-Bellot [Ph. D. thesis (University of Grenoble, 1963)] at larger h+. It does not however apply to a turbulent boundary layer where the mean energy dissipation rate, normalized on either wall or outer variables, is about 30% larger than for the channel flow.

  9. Learning weighted sparse representation of encoded facial normal information for expression-robust 3D face recognition

    KAUST Repository

    Li, Huibin; Di, Huang; Morvan, Jean-Marie; Chen, Liming

    2011-01-01

    This paper proposes a novel approach for 3D face recognition by learning weighted sparse representation of encoded facial normal information. To comprehensively describe 3D facial surface, three components, in X, Y, and Z-plane respectively

  10. Learning weighted sparse representation of encoded facial normal information for expression-robust 3D face recognition

    KAUST Repository

    Li, Huibin

    2011-10-01

    This paper proposes a novel approach for 3D face recognition by learning weighted sparse representation of encoded facial normal information. To comprehensively describe 3D facial surface, three components, in X, Y, and Z-plane respectively, of normal vector are encoded locally to their corresponding normal pattern histograms. They are finally fed to a sparse representation classifier enhanced by learning based spatial weights. Experimental results achieved on the FRGC v2.0 database prove that the proposed encoded normal information is much more discriminative than original normal information. Moreover, the patch based weights learned using the FRGC v1.0 and Bosphorus datasets also demonstrate the importance of each facial physical component for 3D face recognition. © 2011 IEEE.

  11. Laboratory determination of normal operating flow rates with enlarged outlet fittings -- BDF reactors

    Energy Technology Data Exchange (ETDEWEB)

    Waters, E.D.

    1960-02-02

    Experiments have been conducted in the Hydraulics Laboratory, at the request of IPD`s Mechanical Development-A Operation, to determine the energy losses of various enlarged outlet fitting combinations. These experiments were conducted an steady state runs and allow the determination of the normal operating point (flow rate) of a reactor process channel under selected conditions of front header pressure and fuel charge. No attempt is made to make a mechanical or economic evaluation of the particular fitting combinations, although observations were noted which might bear on this evaluation. It is very important for the reader to bear in mind that changing outlet fittings will definitely affect the reactor tube power limits and outlet vater temperature limits. The size of the outlet fittings largely determines the present outlet temperature limits of the old reactors. The flow characteristics of these present fittings cause some degree of pressurization to suppress boiling on the fuel charge and also cause dual Panellit trip protection for certain flow changes and for power surges. Enlargement of the outlet fittings may actually reduce the allowable outlet coolant temperature limits. Since these effects cannot be determined on the apparatus used in these experiments, a complete discussion of this point is not included in this report. However, the seriousness of these effects should be known and carefully analyzed before a final selection of enlarged outlet fittings in made. This report will be one of a series. New reports in the series will be issued as data are obtained for other such outlet fitting combinations or for new concepts of outlet fitting assemblies such as the new nozzle being developed by C. E. Trantz for use on F-reactor stuck gunbarrel tubes.

  12. Private speech of learning disabled and normally achieving children in classroom academic and laboratory contexts.

    Science.gov (United States)

    Berk, L E; Landau, S

    1993-04-01

    Learning disabled (LD) children are often targets for cognitive-behavioral interventions designed to train them in effective use of a self-directed speech. The purpose of this study was to determine if, indeed, these children display immature private speech in the naturalistic classroom setting. Comparisons were made of the private speech, motor accompaniment to task, and attention of LD and normally achieving classmates during academic seatwork. Setting effects were examined by comparing classroom data with observations during academic seatwork and puzzle solving in the laboratory. Finally, a subgroup of LD children symptomatic of attention-deficit hyperactivity disorder (ADHD) was compared with pure LD and normally achieving controls to determine if the presumed immature private speech is a function of a learning disability or externalizing behavior problems. Results indicated that LD children used more task-relevant private speech than controls, an effect that was especially pronounced for the LD/ADHD subgroup. Use of private speech was setting- and task-specific. Implications for intervention and future research methodology are discussed.

  13. Use of scintigraphy for the determination of mucociliary clearance rates in normal, sedated, diseased and exercised horses.

    Science.gov (United States)

    Willoughby, R A; Ecker, G L; McKee, S L; Riddolls, L J

    1991-01-01

    Mucociliary clearance rates from the trachea were determined in normal, sedated, diseased and exercised horses from scintigraphs obtained after an injection of technetium-99m sulphide colloid into the tracheal lumen. The group mean tracheal clearance rate of eight clinically normal horses during 42 trials was 2.06 +/- 0.38 cm/min. Significant between horse differences were found (p less than 0.05). When six and seven of these horses were given xylazine and detomidine hydrochloride, respectively, mean group tracheal clearance rates dropped significantly (p less than 0.05). The decreases from each normal horse's mean tracheal clearance rate ranged from 18 to 54%. There did not appear to be a difference between the tracheal clearance rates (TCRs) of the normal horses and those with chronic respiratory disease. Postexercise evaluations were not significantly different from the pre-exercise TCRs in three clinically normal horses and three horses with chronic obstructive pulmonary disease (p greater than 0.05). This minimally invasive scintigraphic technique for determining TCRs has proved to be useful and reliable. Images Fig. 1. PMID:1790485

  14. [Clinical correlation of hypnagogic hypersynchrony during sleep in normal children and those with learning disability].

    Science.gov (United States)

    Olmos G de Alba, G; Fraire-Martínez, M I; Valenzuela-Romero, R

    One of the electroencephalographic (EEG) patterns that can be mistaken for paroxysmal clinical activity, when not taken into account and especially in children, is hypnagogic hypersynchrony (HH). This consists in generalised, paroxysmal, synchronic, symmetrical, slow, high voltage waves lasting 2 8 seconds, which appear in drowsiness and in stage I. It was observed that this pattern often appeared in children with learning disability (LD). AIMS. To correlate clinical data with the presence of HH during sleep in normal children and those with LD. We assessed 180 children between the ages of 6 12 years with normal neurological development, 130 of which suffered LD and 50 who did not have LD. EEG was performed with sleep deprivation, following the International Federation of Clinical Neurophysiology guidelines. The presence or absence of HH, together with its characteristics, was assessed. Of the children with LD, 35.38% displayed HH and of the children without LD, only 4% displayed HH. Since the characteristics of HH in the children with LD were different to previous descriptions, we put forward criteria with which to evaluate those differences. HH appeared more often in children with LD than in normal children. Qualitative, quantitative (p< 0.05) and morphological changes were found in the paroxysmal activity of HH during the stages of sleep in children with LD.

  15. Some chaotic behaviors in a MCA learning algorithm with a constant learning rate

    International Nuclear Information System (INIS)

    Lv Jiancheng; Yi Zhang

    2007-01-01

    Douglas's minor component analysis algorithm with a constant learning rate has both stability and chaotic dynamical behavior under some conditions. The paper explores such dynamical behavior of this algorithm. Certain stability and chaos of this algorithm are derived. Waveform plots, Lyapunov exponents and bifurcation diagrams are presented to illustrate the existence of chaotic behavior

  16. Deep Learning versus Professional Healthcare Equipment: A Fine-Grained Breathing Rate Monitoring Model

    Directory of Open Access Journals (Sweden)

    Bang Liu

    2018-01-01

    Full Text Available In mHealth field, accurate breathing rate monitoring technique has benefited a broad array of healthcare-related applications. Many approaches try to use smartphone or wearable device with fine-grained monitoring algorithm to accomplish the task, which can only be done by professional medical equipment before. However, such schemes usually result in bad performance in comparison to professional medical equipment. In this paper, we propose DeepFilter, a deep learning-based fine-grained breathing rate monitoring algorithm that works on smartphone and achieves professional-level accuracy. DeepFilter is a bidirectional recurrent neural network (RNN stacked with convolutional layers and speeded up by batch normalization. Moreover, we collect 16.17 GB breathing sound recording data of 248 hours from 109 and another 10 volunteers to train and test our model, respectively. The results show a reasonably good accuracy of breathing rate monitoring.

  17. Probing the effect of human normal sperm morphology rate on cycle outcomes and assisted reproductive methods selection.

    Directory of Open Access Journals (Sweden)

    Bo Li

    Full Text Available Sperm morphology is the best predictor of fertilization potential, and the critical predictive information for supporting assisted reproductive methods selection. Given its important predictive value and the declining reality of semen quality in recent years, the threshold of normal sperm morphology rate (NSMR is being constantly corrected and controversial, from the 4th edition (14% to the 5th version (4%. We retrospectively analyzed 4756 cases of infertility patients treated with conventional-IVF(c-IVF or ICSI, which were divided into three groups according to NSMR: ≥14%, 4%-14% and <4%. Here, we demonstrate that, with decrease in NSMR(≥14%, 4%-14%, <4%, in the c-IVF group, the rate of fertilization, normal fertilization, high-quality embryo, multi-pregnancy and birth weight of twins gradually decreased significantly (P<0.05, while the miscarriage rate was significantly increased (p<0.01 and implantation rate, clinical pregnancy rate, ectopic pregnancy rate, preterm birth rate, live birth rate, sex ratio, and birth weight(Singleton showed no significant change. In the ICSI group, with decrease in NSMR (≥14%, 4%-14%, <4%, high-quality embryo rate, multi-pregnancy rate and birth weight of twins were gradually decreased significantly (p<0.05, while other parameters had no significant difference. Considering the clinical assisted methods selection, in the NFMR ≥14% group, normal fertilization rate of c-IVF was significantly higher than the ICSI group (P<0.05, in the 4%-14% group, birth weight (twins of c-IVF were significantly higher than the ICSI group, in the <4% group, miscarriage of IVF was significantly higher than the ICSI group. Therefore, we conclude that NSMR is positively related to embryo reproductive potential, and when NSMR<4% (5th edition, ICSI should be considered first, while the NSMR≥4%, c-IVF assisted reproduction might be preferred.

  18. The effect of inertia, viscous damping, temperature and normal stress on chaotic behaviour of the rate and state friction model

    Science.gov (United States)

    Sinha, Nitish; Singh, Arun K.; Singh, Trilok N.

    2018-04-01

    A fundamental understanding of frictional sliding at rock surfaces is of practical importance for nucleation and propagation of earthquakes and rock slope stability. We investigate numerically the effect of different physical parameters such as inertia, viscous damping, temperature and normal stress on the chaotic behaviour of the two state variables rate and state friction (2sRSF) model. In general, a slight variation in any of inertia, viscous damping, temperature and effective normal stress reduces the chaotic behaviour of the sliding system. However, the present study has shown the appearance of chaos for the specific values of normal stress before it disappears again as the normal stress varies further. It is also observed that magnitude of system stiffness at which chaotic motion occurs, is less than the corresponding value of critical stiffness determined by using the linear stability analysis. These results explain the practical observation why chaotic nucleation of an earthquake is a rare phenomenon as reported in literature.

  19. Application of specific gravity method for normalization of urinary excretion rates of radionuclides

    International Nuclear Information System (INIS)

    Thakur, Smita S.; Yadav, J.R.; Rao, D.D.

    2015-01-01

    In vitro bioassay monitoring is based on the determination of activity concentration in biological samples excreted from the body and is most suitable for alpha and beta emitters. For occupational workers handling actinides in reprocessing facilities possibility of internal exposure exists and urine assay is preferred method for monitoring such exposure. Urine samples collected for 24 h duration, is the true representative of bioassay sample and hence in the case of insufficient collection time, specific gravity applied method of normalization of urine sample is used. The present study reports the data of specific gravity generated for controlled group of Indian population by the use of densitometer and its application in urinary sample activity normalization. The average specific gravity value obtained for the controlled group was 1.008±0.005 gm/ml. (author)

  20. The influence of dose fractionation and dose rate on normal tissue responses

    International Nuclear Information System (INIS)

    Barendsen, G.W.

    1982-01-01

    An analysis of responses of a variety of normal tissues in animals to fractionated irradiations has been made with the aim of developing a formalism for the prediction of tolerance doses as a function of the dose per fraction and the overall treatment time. An important feature of the formalism is that it is directly based on radiological insights and therefore provides a logical concept to account for the diversity of tissue responses. (Auth.)

  1. Accelerating regional atrophy rates in the progression from normal aging to Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Sluimer, Jasper D. [VU University Medical Centre, Department of Diagnostic Radiology, Amsterdam (Netherlands); VU University Medical Centre, Alzheimer Centre, Amsterdam (Netherlands); VU University Medical Centre, Image Analysis Centre, Amsterdam (Netherlands); VU University Medical Centre, Department of Diagnostic Radiology and Alzheimer Centre, PO Box 7057, Amsterdam (Netherlands); Flier, Wiesje M. van der; Scheltens, Philip [VU University Medical Centre, Alzheimer Centre, Amsterdam (Netherlands); VU University Medical Centre, Department of Neurology, Amsterdam (Netherlands); Karas, Giorgos B.; Barkhof, Frederik [VU University Medical Centre, Department of Diagnostic Radiology, Amsterdam (Netherlands); VU University Medical Centre, Alzheimer Centre, Amsterdam (Netherlands); VU University Medical Centre, Image Analysis Centre, Amsterdam (Netherlands); Schijndel, Ronald van [VU University Medical Centre, Image Analysis Centre, Amsterdam (Netherlands); VU University Medical Centre, Department of Informatics, Amsterdam (Netherlands); Barnes, Josephine; Boyes, Richard G. [UCL, Institute of Neurology, Dementia Research Centre, London (United Kingdom); Cover, Keith S. [VU University Medical Centre, Department of Physics and Medical Technology, Amsterdam (Netherlands); Olabarriaga, Silvia D. [University of Amsterdam, Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Academic Medical Centre, Amsterdam (Netherlands); Fox, Nick C. [VU University Medical Centre, Department of Neurology, Amsterdam (Netherlands); UCL, Institute of Neurology, Dementia Research Centre, London (United Kingdom); Vrenken, Hugo [VU University Medical Centre, Alzheimer Centre, Amsterdam (Netherlands); VU University Medical Centre, Image Analysis Centre, Amsterdam (Netherlands); VU University Medical Centre, Department of Physics and Medical Technology, Amsterdam (Netherlands)

    2009-12-15

    We investigated progression of atrophy in vivo, in Alzheimer's disease (AD), and mild cognitive impairment (MCI). We included 64 patients with AD, 44 with MCI and 34 controls with serial MRI examinations (interval 1.8 {+-} 0.7 years). A nonlinear registration algorithm (fluid) was used to calculate atrophy rates in six regions: frontal, medial temporal, temporal (extramedial), parietal, occipital lobes and insular cortex. In MCI, the highest atrophy rate was observed in the medial temporal lobe, comparable with AD. AD patients showed even higher atrophy rates in the extramedial temporal lobe. Additionally, atrophy rates in frontal, parietal and occipital lobes were increased. Cox proportional hazard models showed that all regional atrophy rates predicted conversion to AD. Hazard ratios varied between 2.6 (95% confidence interval (CI) = 1.1-6.2) for occipital atrophy and 15.8 (95% CI = 3.5-71.8) for medial temporal lobe atrophy. In conclusion, atrophy spreads through the brain with development of AD. MCI is marked by temporal lobe atrophy. In AD, atrophy rate in the extramedial temporal lobe was even higher. Moreover, atrophy rates also accelerated in parietal, frontal, insular and occipital lobes. Finally, in nondemented elderly, medial temporal lobe atrophy was most predictive of progression to AD, demonstrating the involvement of this region in the development of AD. (orig.)

  2. Accelerating regional atrophy rates in the progression from normal aging to Alzheimer's disease

    International Nuclear Information System (INIS)

    Sluimer, Jasper D.; Flier, Wiesje M. van der; Scheltens, Philip; Karas, Giorgos B.; Barkhof, Frederik; Schijndel, Ronald van; Barnes, Josephine; Boyes, Richard G.; Cover, Keith S.; Olabarriaga, Silvia D.; Fox, Nick C.; Vrenken, Hugo

    2009-01-01

    We investigated progression of atrophy in vivo, in Alzheimer's disease (AD), and mild cognitive impairment (MCI). We included 64 patients with AD, 44 with MCI and 34 controls with serial MRI examinations (interval 1.8 ± 0.7 years). A nonlinear registration algorithm (fluid) was used to calculate atrophy rates in six regions: frontal, medial temporal, temporal (extramedial), parietal, occipital lobes and insular cortex. In MCI, the highest atrophy rate was observed in the medial temporal lobe, comparable with AD. AD patients showed even higher atrophy rates in the extramedial temporal lobe. Additionally, atrophy rates in frontal, parietal and occipital lobes were increased. Cox proportional hazard models showed that all regional atrophy rates predicted conversion to AD. Hazard ratios varied between 2.6 (95% confidence interval (CI) = 1.1-6.2) for occipital atrophy and 15.8 (95% CI = 3.5-71.8) for medial temporal lobe atrophy. In conclusion, atrophy spreads through the brain with development of AD. MCI is marked by temporal lobe atrophy. In AD, atrophy rate in the extramedial temporal lobe was even higher. Moreover, atrophy rates also accelerated in parietal, frontal, insular and occipital lobes. Finally, in nondemented elderly, medial temporal lobe atrophy was most predictive of progression to AD, demonstrating the involvement of this region in the development of AD. (orig.)

  3. Rates of convergence and asymptotic normality of curve estimators for ergodic diffusion processes

    NARCIS (Netherlands)

    J.H. van Zanten (Harry)

    2000-01-01

    textabstractFor ergodic diffusion processes, we study kernel-type estimators for the invariant density, its derivatives and the drift function. We determine rates of convergence and find the joint asymptotic distribution of the estimators at different points.

  4. Normalized impact factor (NIF): an adjusted method for calculating the citation rate of biomedical journals.

    Science.gov (United States)

    Owlia, P; Vasei, M; Goliaei, B; Nassiri, I

    2011-04-01

    The interests in journal impact factor (JIF) in scientific communities have grown over the last decades. The JIFs are used to evaluate journals quality and the papers published therein. JIF is a discipline specific measure and the comparison between the JIF dedicated to different disciplines is inadequate, unless a normalization process is performed. In this study, normalized impact factor (NIF) was introduced as a relatively simple method enabling the JIFs to be used when evaluating the quality of journals and research works in different disciplines. The NIF index was established based on the multiplication of JIF by a constant factor. The constants were calculated for all 54 disciplines of biomedical field during 2005, 2006, 2007, 2008 and 2009 years. Also, ranking of 393 journals in different biomedical disciplines according to the NIF and JIF were compared to illustrate how the NIF index can be used for the evaluation of publications in different disciplines. The findings prove that the use of the NIF enhances the equality in assessing the quality of research works produced by researchers who work in different disciplines. Copyright © 2010 Elsevier Inc. All rights reserved.

  5. Measurement of urinary albumin excretion rate (AER) in normal and diabetic subjects

    International Nuclear Information System (INIS)

    Giampetro, O.; Clerico, A.; Cruschelli, L.; Miccoli, R.; Dipalma, L.; Navalesi, R.

    1987-01-01

    The chemico-clinical characteristics of two commercial RIA kits for the measurement of urinary albumin excretion in normal and diabetic subjects were compared. The chief difference between the two methods concerns the bound/free separation of the antigen, since one employs the second antybody plus PEG (Sclavo Kit), while the other uses the solid phase [antiserum bound to sepharose (Pharmacia kit)]. The two RIA methods have demonstrated a similar degree of sensitivity, feasibility and cost. The precision of the two RIAs was also similar, although the Sclavo kit has shown a better precision for lower albumin concentrations and the Pharmacia kit for higher values. In diabetic patients, elevated urinary albumin concentrations (>60 mg/L) have been found more frequently than low values (<5 mg/L); hence the Pharmacia kit seems to be preferable, because it less frequently needs dilution of urinary sample for measuring with a better precision supranormal urinary albumin values. A significant bias (about 15%) was found between the two RIAs. Bias between different albumin RIA methods could partially explain the differences of normal values previously reported in the literature

  6. Efficient Computation of Transition State Resonances and Reaction Rates from a Quantum Normal Form

    NARCIS (Netherlands)

    Schubert, Roman; Waalkens, Holger; Wiggins, Stephen

    2006-01-01

    A quantum version of a recent formulation of transition state theory in phase space is presented. The theory developed provides an algorithm to compute quantum reaction rates and the associated Gamov-Siegert resonances with very high accuracy. The algorithm is especially efficient for

  7. 46 CFR 401.428 - Basic rates and charges for carrying a U.S. pilot beyond normal change point or for boarding at...

    Science.gov (United States)

    2010-10-01

    ... boarding point, the ship shall pay at the rate of $719 per day or part thereof, plus reasonable travel... normal change point or for boarding at other than the normal boarding point. 401.428 Section 401.428... carrying a U.S. pilot beyond normal change point or for boarding at other than the normal boarding point...

  8. The rate of DNA synthesis in normal human and ataxia telangiectasia cells after exposure to X-irradiation

    International Nuclear Information System (INIS)

    Wit, J. de; Bootsma, D.; Jaspers, N.G.J.; Rijksverdedigingsorganisatie TNO, Rijswijk

    1981-01-01

    The rate of DNA synthesis was studied in normal cell strains and in strains from patients suffering from the inherited disorder ataxia telangiectasia (AT). After exposure to relatively low doses of oxic X-rays (0- 4 krad) DNA synthesis was depressed in AT cell strains to a significantly lesser extent than in normal cells. This response was observed in both an excision-deficient and an excision-proficient strain. In contrast, there was no difference in DNA-synthesis inhibition between AT and normal cells after UV exposure. After X-irradiation of cells from patients with xeroderma pigmentosum, both complementation group A and XP variants, the observed rate of DNA synthesis was equal to that in normal cells. An exception was the strain XP3BR which has been shown to be X-ray-sensitive. This strain exhibited diminished DNA synthesis inhibition after X-ray doses below 1 krad. These data suggest a relationship between hypersensitivity to X-rays and diminished depression of DNA synthesis. (orig.)

  9. Frequency modulation excursion and rate discrimination in normal-hearing and hearing-impaired listeners

    DEFF Research Database (Denmark)

    Schindwolf, Isabel; Vatti, Marianna; Santurette, Sébastien

    Most natural sounds contain frequency fluctuations over time such as changes in their fundamental frequency, non-periodic speech formant transitions, or periodic fluctuations like musical vibrato. These are sometimes characterized as frequency modulation (FM) with a given excursion (FMe) and rate......, this study investigated the effects of age and SNHL on FMe and FMr difference limens (DLs) for reference values typical of frequency fluctuations observed in speech and music signals....

  10. Durability predictions from rate of diffusion testing of normal portland cement, fly ash, and slag concrete

    International Nuclear Information System (INIS)

    Philipose, K.E.

    1991-09-01

    A waste repository for the belowground disposal of low-level radioactive waste, labelled IRUS (Intrusion Resistant Underground Structure), is planned at the Chalk River Laboratories. It relies greatly on the durability of concrete for a minimum of 500 years of service life. A research program based on laboratory testing to design a durable concrete and predict its useful engineered service life is in progress. The durability of concrete depends on its resistance to deterioration from both internal and external causes. Since the rate of degradation depends to a major extent on the rate of ingress of aggressive ions into concrete, laboratory testing is in progress to establish the diffusion rates of chlorides and sulphate ions. A total of 1000 concrete specimens and 500 paste specimens are being exposed at 22 degrees and 45 degrees C to twenty-five different combinations of corrosive agents, including CO 2 . Procedures to measure the ionic penetration profile and to determine the factors controlling diffusion of ions in the various concretes have been developed. The paper presents the initial results from the research program and the longevity predictions to qualify concretes for the IRUS waste repository, based on 16 months of diffusion testing on laboratory specimens

  11. Comparability of Self-Concept among Normal Achievers and Children with Learning Difficulties within a Greek Context.

    Science.gov (United States)

    Leonadari, Angeliki

    1994-01-01

    Assessed Greek third through sixth graders on the Perceived Competence Scale for Children (PCSC). Subjects were normally achieving (NA) and low achieving students and a special class (SC) of students identified as at risk for learning difficulties. The SC students scored lower than the NA students on the PCSC global self-worth, competence affect,…

  12. A fast simulation method for the Log-normal sum distribution using a hazard rate twisting technique

    KAUST Repository

    Rached, Nadhir B.

    2015-06-08

    The probability density function of the sum of Log-normally distributed random variables (RVs) is a well-known challenging problem. For instance, an analytical closed-form expression of the Log-normal sum distribution does not exist and is still an open problem. A crude Monte Carlo (MC) simulation is of course an alternative approach. However, this technique is computationally expensive especially when dealing with rare events (i.e. events with very small probabilities). Importance Sampling (IS) is a method that improves the computational efficiency of MC simulations. In this paper, we develop an efficient IS method for the estimation of the Complementary Cumulative Distribution Function (CCDF) of the sum of independent and not identically distributed Log-normal RVs. This technique is based on constructing a sampling distribution via twisting the hazard rate of the original probability measure. Our main result is that the estimation of the CCDF is asymptotically optimal using the proposed IS hazard rate twisting technique. We also offer some selected simulation results illustrating the considerable computational gain of the IS method compared to the naive MC simulation approach.

  13. A fast simulation method for the Log-normal sum distribution using a hazard rate twisting technique

    KAUST Repository

    Rached, Nadhir B.; Benkhelifa, Fatma; Alouini, Mohamed-Slim; Tempone, Raul

    2015-01-01

    The probability density function of the sum of Log-normally distributed random variables (RVs) is a well-known challenging problem. For instance, an analytical closed-form expression of the Log-normal sum distribution does not exist and is still an open problem. A crude Monte Carlo (MC) simulation is of course an alternative approach. However, this technique is computationally expensive especially when dealing with rare events (i.e. events with very small probabilities). Importance Sampling (IS) is a method that improves the computational efficiency of MC simulations. In this paper, we develop an efficient IS method for the estimation of the Complementary Cumulative Distribution Function (CCDF) of the sum of independent and not identically distributed Log-normal RVs. This technique is based on constructing a sampling distribution via twisting the hazard rate of the original probability measure. Our main result is that the estimation of the CCDF is asymptotically optimal using the proposed IS hazard rate twisting technique. We also offer some selected simulation results illustrating the considerable computational gain of the IS method compared to the naive MC simulation approach.

  14. Prediction of the time-dependent failure rate for normally operating components taking into account the operational history

    International Nuclear Information System (INIS)

    Vrbanic, I.; Simic, Z.; Sljivac, D.

    2008-01-01

    The prediction of the time-dependent failure rate has been studied, taking into account the operational history of a component used in applications such as system modeling in a probabilistic safety analysis in order to evaluate the impact of equipment aging and maintenance strategies on the risk measures considered. We have selected a time-dependent model for the failure rate which is based on the Weibull distribution and the principles of proportional age reduction by equipment overhauls. Estimation of the parameters that determine the failure rate is considered, including the definition of the operational history model and likelihood function for the Bayesian analysis of parameters for normally operating repairable components. The operational history is provided as a time axis with defined times of overhauls and failures. An example for demonstration is described with prediction of the future behavior for seven different operational histories. (orig.)

  15. Performance improvement of two-dimensional EUV spectroscopy based on high frame rate CCD and signal normalization method

    International Nuclear Information System (INIS)

    Zhang, H.M.; Morita, S.; Ohishi, T.; Goto, M.; Huang, X.L.

    2014-01-01

    In the Large Helical Device (LHD), the performance of two-dimensional (2-D) extreme ultraviolet (EUV) spectroscopy with wavelength range of 30-650A has been improved by installing a high frame rate CCD and applying a signal intensity normalization method. With upgraded 2-D space-resolved EUV spectrometer, measurement of 2-D impurity emission profiles with high horizontal resolution is possible in high-density NBI discharges. The variation in intensities of EUV emission among a few discharges is significantly reduced by normalizing the signal to the spectral intensity from EUV_—Long spectrometer which works as an impurity monitor with high-time resolution. As a result, high resolution 2-D intensity distribution has been obtained from CIV (384.176A), CV(2x40.27A), CVI(2x33.73A) and HeII(303.78A). (author)

  16. Episodic memory deficits slow down the dynamics of cognitive procedural learning in normal ageing

    Science.gov (United States)

    Beaunieux, Hélène; Hubert, Valérie; Pitel, Anne Lise; Desgranges, Béatrice; Eustache, Francis

    2009-01-01

    Cognitive procedural learning is characterized by three phases, each involving distinct processes. Considering the implication of the episodic memory in the first cognitive stage, the impairment of this memory system might be responsible for a slowing down of the cognitive procedural learning dynamics in the course of aging. Performances of massed cognitive procedural learning were evaluated in older and younger participants using the Tower of Toronto task. Nonverbal intelligence and psychomotor abilities were used to analyze procedural dynamics, while episodic memory and working memory were assessed to measure their respective contributions to learning strategies. This experiment showed that older participants did not spontaneously invoke episodic memory and presented a slowdown in the cognitive procedural learning associated with a late involvement of working memory. These findings suggest that the slowdown in the cognitive procedural learning may be linked with the implementation of different learning strategies less involving episodic memory in older subjects. PMID:18654928

  17. Effects of adipose tissue distribution on maximum lipid oxidation rate during exercise in normal-weight women.

    Science.gov (United States)

    Isacco, L; Thivel, D; Duclos, M; Aucouturier, J; Boisseau, N

    2014-06-01

    Fat mass localization affects lipid metabolism differently at rest and during exercise in overweight and normal-weight subjects. The aim of this study was to investigate the impact of a low vs high ratio of abdominal to lower-body fat mass (index of adipose tissue distribution) on the exercise intensity (Lipox(max)) that elicits the maximum lipid oxidation rate in normal-weight women. Twenty-one normal-weight women (22.0 ± 0.6 years, 22.3 ± 0.1 kg.m(-2)) were separated into two groups of either a low or high abdominal to lower-body fat mass ratio [L-A/LB (n = 11) or H-A/LB (n = 10), respectively]. Lipox(max) and maximum lipid oxidation rate (MLOR) were determined during a submaximum incremental exercise test. Abdominal and lower-body fat mass were determined from DXA scans. The two groups did not differ in aerobic fitness, total fat mass, or total and localized fat-free mass. Lipox(max) and MLOR were significantly lower in H-A/LB vs L-A/LB women (43 ± 3% VO(2max) vs 54 ± 4% VO(2max), and 4.8 ± 0.6 mg min(-1)kg FFM(-1)vs 8.4 ± 0.9 mg min(-1)kg FFM(-1), respectively; P normal-weight women, a predominantly abdominal fat mass distribution compared with a predominantly peripheral fat mass distribution is associated with a lower capacity to maximize lipid oxidation during exercise, as evidenced by their lower Lipox(max) and MLOR. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  18. Normal values of glomerular filtration rate in geriatrics in Bandung and its correlation with serum cystatin-C levels

    International Nuclear Information System (INIS)

    Resnaldi, A.; Yuliani, A.; Hidayat, B.; Kartamihardja, A.H.S.

    2007-01-01

    Full text: Determination of the normal values of glomerular filtration rate (GFR) is an essential part of the evaluation of patient with kidney disease. GFR almost linearly decreases with age at a mean annual rate of 0.8 ml/min/1.73 m2 over the age of 30 years old. According to NHANES III mean GFR for population with age > 60 years was 80 mL/min/1.73 m2. It is recommended for each centre to determine their own normal values of GFR for different age groups particularly in geriatric population. Recently, serum cystatin-C has been proposed as a new endogenous marker of glomerular filtration rate. Aim of the study was to determination of normal values of glomerular filtration rate (GFR) in geriatrics in Bandung and its correlation with serum Cystatin-C levels. Subjects were 24 males and 36 females (mean age 66.71 ± 6.7 years; range 60-87 yrs), without any renal and/or systemic disease. Creatinine clearance was estimated by using Cockroft-Gault formula and serum cystatin-C level were determined by using particle enhanced immunonephelometric method, while GFR values were determined by external body counting methods using Tc-99m DTPA ( Gates' methods ). Pearson correlation was used to determine correlation between variables and a P value < 0.05 is considered significant. Results and Discussion. Mean total GFR was 67.57 ml/min/1.73 m2 (SD ± 16.02), range from 45 to 100 ml/min/1.73 m2. Mean total GFR for male was 69.46 ml/min/1.73 m2, and female was 66.31 ml/min/1.73 m2, the difference was statistically significant (p < 0.05). The results were lower than NHANES III values. There was a better correlation between total GFR and cystatin-C level (r = -0.522 and p < 0.001) compared to total GFR and creatinine clearance (r 0.306 and p < 0.005). Mean creatinine clearance was 57.93 ml/min and serum cystatin-C was 0.97 mg/dl, the correlation was statistically significant (r -0.414 and p < 0.005). Conclusions: The normal values of GFR in geriatric population in Bandung were 69

  19. Patient-dependent count-rate adaptive normalization for PET detector efficiency with delayed-window coincidence events

    International Nuclear Information System (INIS)

    Niu, Xiaofeng; Ye, Hongwei; Xia, Ting; Asma, Evren; Gagnon, Daniel; Wang, Wenli; Winkler, Mark

    2015-01-01

    Quantitative PET imaging is widely used in clinical diagnosis in oncology and neuroimaging. Accurate normalization correction for the efficiency of each line-of- response is essential for accurate quantitative PET image reconstruction. In this paper, we propose a normalization calibration method by using the delayed-window coincidence events from the scanning phantom or patient. The proposed method could dramatically reduce the ‘ring’ artifacts caused by mismatched system count-rates between the calibration and phantom/patient datasets. Moreover, a modified algorithm for mean detector efficiency estimation is proposed, which could generate crystal efficiency maps with more uniform variance. Both phantom and real patient datasets are used for evaluation. The results show that the proposed method could lead to better uniformity in reconstructed images by removing ring artifacts, and more uniform axial variance profiles, especially around the axial edge slices of the scanner. The proposed method also has the potential benefit to simplify the normalization calibration procedure, since the calibration can be performed using the on-the-fly acquired delayed-window dataset. (paper)

  20. Speech Motor Sequence Learning: Acquisition and Retention in Parkinson Disease and Normal Aging

    Science.gov (United States)

    Whitfield, Jason A.; Goberman, Alexander M.

    2017-01-01

    Purpose: The aim of the current investigation was to examine speech motor sequence learning in neurologically healthy younger adults, neurologically healthy older adults, and individuals with Parkinson disease (PD) over a 2-day period. Method: A sequential nonword repetition task was used to examine learning over 2 days. Participants practiced a…

  1. Effect of soft drinks on proximal plaque pH at normal and low salivary secretion rates.

    Science.gov (United States)

    Johansson, Ann-Katrin; Lingström, Peter; Birkhed, Dowen

    2007-11-01

    The aim of this study was to investigate the effect of different types of drinks on plaque pH during normal and drug-induced low salivary secretion rates. Three drinks were tested in 10 healthy adult subjects: 1) Coca-Cola regular, 2) Coca-Cola light, and 3) fresh orange juice. pH was measured in the maxillary incisor and premolar region with the microtouch method. The area under the pH curve (AUC) was calculated. During normal salivary condition, mouth-rinsing with Coca-Cola regular resulted in a slightly more pronounced drop in pH during the first few minutes than it did with orange juice. After this initial phase, both products showed similar and relatively slow pH recovery. Coca-Cola light also resulted in low pH values during the very first minutes, but thereafter in a rapid recovery back to baseline. During dry mouth conditions, the regular Cola drink showed a large initial drop in pH, and slightly more pronounced than for orange juice. After the initial phase, both products had a similar and slow recovery back to baseline. At most time-points, AUC was significantly greater in dry conditions compared to normal conditions for Coca-Cola regular and orange juice, but not for Coca-Cola light. Coca-Cola light generally showed a significantly smaller AUC than Coca-Cola regular and orange juice. The main conclusion from this study is that a low salivary secretion rate may accentuate the fall in pH in dental plaque after gentle mouth-rinsing with soft drinks.

  2. Differences in Learning Strategies, Goal Orientations, and Self-Concept between Overachieving, Normal-Achieving, and Underachieving Secondary Students

    Science.gov (United States)

    Castejón, Juan L.; Gilar, Raquel; Veas, Alejandro; Miñano, Pablo

    2016-01-01

    The aims of this work were to identify and establish differential characteristics in learning strategies, goal orientations, and self-concept between overachieving, normal-achieving and underachieving secondary students. A total of 1400 Spanish first and second year high school students from the South-East geographical area participated in this study. Three groups of students were established: a group with underachieving students, a group with a normal level of achievement, and a third group with overachieving students. The students were assigned to each group depending on the residual punctuations obtained from a multiple regression analysis in which the punctuation of an IQ test was the predictor and a measure composed of the school grades of nine subjects was the criteria. The results of one-way ANOVA and the Games-Howell post-hoc test showed that underachieving students had significantly lower punctuations in all of the measures of learning strategies and learning goals, as well as all of the academic self-concept, personal self-concept, parental relationship, honesty, and personal stability factors. In contrast, overachieving students had higher punctuations than underachieving students in the same variables and higher punctuations than normal-achieving students in most of the variables in which significant differences were detected. These results have clear educational implications. PMID:27729879

  3. Radiobiological influence of megavoltage electron pulses of ultra-high pulse dose rate on normal tissue cells.

    Science.gov (United States)

    Laschinsky, Lydia; Karsch, Leonhard; Leßmann, Elisabeth; Oppelt, Melanie; Pawelke, Jörg; Richter, Christian; Schürer, Michael; Beyreuther, Elke

    2016-08-01

    Regarding the long-term goal to develop and establish laser-based particle accelerators for a future radiotherapeutic treatment of cancer, the radiobiological consequences of the characteristic short intense particle pulses with ultra-high peak dose rate, but low repetition rate of laser-driven beams have to be investigated. This work presents in vitro experiments performed at the radiation source ELBE (Electron Linac for beams with high Brilliance and low Emittance). This accelerator delivered 20-MeV electron pulses with ultra-high pulse dose rate of 10(10) Gy/min either at the low pulse frequency analogue to previous cell experiments with laser-driven electrons or at high frequency for minimizing the prolonged dose delivery and to perform comparison irradiation with a quasi-continuous electron beam analogue to a clinically used linear accelerator. The influence of the different electron beam pulse structures on the radiobiological response of the normal tissue cell line 184A1 and two primary fibroblasts was investigated regarding clonogenic survival and the number of DNA double-strand breaks that remain 24 h after irradiation. Thereby, no considerable differences in radiation response were revealed both for biological endpoints and for all probed cell cultures. These results provide evidence that the radiobiological effectiveness of the pulsed electron beams is not affected by the ultra-high pulse dose rates alone.

  4. Radiobiological influence of megavoltage electron pulses of ultra-high pulse dose rate on normal tissue cells

    International Nuclear Information System (INIS)

    Laschinsky, Lydia; Karsch, Leonhard; Schuerer, Michael; Lessmann, Elisabeth; Beyreuther, Elke; Oppelt, Melanie; Pawelke, Joerg; Richter, Christian

    2016-01-01

    Regarding the long-term goal to develop and establish laser-based particle accelerators for a future radiotherapeutic treatment of cancer, the radiobiological consequences of the characteristic short intense particle pulses with ultra-high peak dose rate, but low repetition rate of laser-driven beams have to be investigated. This work presents in vitro experiments performed at the radiation source ELBE (Electron Linac for beams with high Brilliance and low Emittance). This accelerator delivered 20-MeV electron pulses with ultra-high pulse dose rate of 10"1"0 Gy/min either at the low pulse frequency analogue to previous cell experiments with laser-driven electrons or at high frequency for minimizing the prolonged dose delivery and to perform comparison irradiation with a quasi-continuous electron beam analogue to a clinically used linear accelerator. The influence of the different electron beam pulse structures on the radiobiological response of the normal tissue cell line 184A1 and two primary fibroblasts was investigated regarding clonogenic survival and the number of DNA double-strand breaks that remain 24 h after irradiation. Thereby, no considerable differences in radiation response were revealed both for biological endpoints and for all probed cell cultures. These results provide evidence that the radiobiological effectiveness of the pulsed electron beams is not affected by the ultra-high pulse dose rates alone. (orig.)

  5. The effect of eating salt with iodine on the normal values of thyroid 131I uptake rate

    International Nuclear Information System (INIS)

    Zhang Chunyan; Wang Huawen; Li Guirong; Chen Chunmei; Zhang Lixia; Yu Yuehua

    2002-01-01

    131 I uptake rates of control group, which stop eating salt with iodine for over six weeks, eating salt with iodine group, the hyperthyroidism group are determined in 2 h, 6 h and 24 h respectively. The results show 131 I uptake rate of eating salt with iodine group are (7.7 +- 4.2)% in 2 h, (13.8 +- 5.3)% in 6 h and (21.9 +- 7.7)% in 24 h. There are no difference between sex. There is significance of difference (P 131 I uptake rates between the hyperthyroidism group of eating salt with iodine and control group is 5.0%, and eating salt with iodine group is 22.5%. To determine the thyroid iodine uptake rate in the patients who did not stop eating salt with iodine, the ranges of normal values must be defined. This result could be as a standard to diagnose the patients of hyperthyroidism of eating salt with iodine

  6. LEARNERS’ ATTITUDES TOWARDS ONLINE LANGUAGE LEARNING; AND CORRESPONDING SUCCESS RATES

    Directory of Open Access Journals (Sweden)

    Emrah CINKARA

    2013-04-01

    Full Text Available Online teaching has long been a key area of interest recently in every field of education as well as English language teaching. Numerous hardware tools, such as, mp3 players, mobile devices, and so on; and software applications, such as, podcasts, wikis, learning management systems, and so on, have been used in distance and online instruction and they have proved to be useful in facilitating learning individually (Finger, Sun, & Jamieson-Proctor, 2010. Learning management systems (LMS provide a virtual environment and various tools to support learning. The current institution where the researchers work deliver two 2-credit online English courses for a specific group of learners at a state university in south-eastern Turkey by using Modular Object Oriented Distance Learning Environment (MOODLE. Moodle is an open code LMS which provides teachers and course developers with numerous online tools to enhance distance learning/teaching environment. The course has both a synchronous and asynchronous instruction. Synchronous and asynchronous instructions are associated with the delivery of content in campus-based environments; however, their role differs in off the campus environments as they solve the problems of distance learners. Universities, colleges, and other education institutions are integrating online learning into every aspect of higher education. Many teachers and faculty members at higher education institutions who already run face-to-face courses have a website to post lecture notes or slide presentations as well as other course material. There is no doubt that these are effective strategies to expand teaching efforts. Still, there are other educators who design and teach totally online classes. The main purpose of this paper is to evaluate learners’ attitudes towards these online language courses, and there are two objectives of this research. The first one is to discover learners’ attitudes towards the online English course; and the

  7. Learning rates in supervised and unsupervised intelligent systems

    International Nuclear Information System (INIS)

    Hora, S.C.

    1986-01-01

    Classifying observations from a mixture distribution is considered a simple model for learning. Existing results are integrated to obtain asymptotically optimal estimators of the classification rule. The asymptotic relative efficiencies show that a tutored learner is considerably more efficient on difficult problems, but only slightly more efficient on easy problems. This suggests a combined method that seeks instruction on hard cases

  8. Nuclear Power Learning and Deployment Rates; Disruption and Global Benefits Forgone

    OpenAIRE

    Peter A. Lang

    2017-01-01

    This paper presents evidence of the disruption of a transition from fossil fuels to nuclear power, and finds the benefits forgone as a consequence are substantial. Learning rates are presented for nuclear power in seven countries, comprising 58% of all power reactors ever built globally. Learning rates and deployment rates changed in the late-1960s and 1970s from rapidly falling costs and accelerating deployment to rapidly rising costs and stalled deployment. Historical nuclear global capacit...

  9. Improving historical spelling normalization with bi-directional LSTMs and multi-task learning

    OpenAIRE

    Bollmann, Marcel; Søgaard, Anders

    2016-01-01

    Natural-language processing of historical documents is complicated by the abundance of variant spellings and lack of annotated data. A common approach is to normalize the spelling of historical words to modern forms. We explore the suitability of a deep neural network architecture for this task, particularly a deep bi-LSTM network applied on a character level. Our model compares well to previously established normalization algorithms when evaluated on a diverse set of texts from Early New Hig...

  10. The support of the ultrasonography of the shoulder in the diagnosis of polymyalgia rheumatica with normal erythrocyte sedimentation rate

    Directory of Open Access Journals (Sweden)

    G. Frisone

    2011-06-01

    Full Text Available The Polymyalgia Rheumatica (PMR is a cronic inflammatory syndrome that affects the elderly population and whose diagnosis is mainly based on clinical criteria taking little advantage of the latest innovatory methods of diagnostic imaging, for instance ultrasonography. Although it is generally characterised by increasing of inflammation values as well as pain and stiffness on the shoulder and pelvic girdles, there is a significant percentage of patients with PMR whose erythrocyte sedimentation rate (ESR is normal; in this case to make a diagnosis is difficult. The purpose of our study is to demonstrate how useful ultrasound investigations on the shoulders joints could be in order to make a diagnosis of PMR, especially for those patients with atypical normal ESR. Our case control study included 23 patients with atypical PMR and 88 patients with standard symptomatic PMR; both groups underwent shoulder ultrasound scans before receiving steroid therapy. As it has been previously shown, the ultrasound method is able to detect distinctive aspects in the joints and tissues of the patients with PMR; so that we could find that 90% of the patients with PMR of both groups suffered from bilateral subdeltoid bursitis. This disorder is seldom found in healthy people and consequently its presence could be considered a useful diagnostic test/check for/of PMR independently from ESR values.

  11. Heart rate variability and QT dispersion study in brain death patients and comatose patients with normal brainstem function

    International Nuclear Information System (INIS)

    Vakilian, A.R.; Iranmanesh, F.; Nadimi, A.E.; Kahnali, J.A.

    2011-01-01

    To compare heart rate variability (HRV) and QT dispersion in comatose patients with normal brainstem function and with brain death. Fourteen brain death patients with clinical signs of imminent brain death and 15 comatose patients were examined by neurologist in intensive care unit. HRV, RR interval and QT dispersion on ECG were assessed for 24 hours in both groups. Independent t-test and chi-square test were used for statistical analysis to determine significance which was set at p < 0.05. According to Holter findings, mean of standard deviation of RR-interval in the comatose and brain death groups was 48.33 and 35 respectively (p = 0.045). Mean of covariance coefficient of RR-interval was 0.065 in the comatose group and 0.043 in the brain deaths (p = 0.006). QT dispersion was not significant difference in two groups. HRV and RR-interval analysis appeared as an early finding for the diagnosis of brainstem death in comparison to comatose patients with normal brainstem function. QT dispersion had not significant in this regard. (author)

  12. Learning Programming Technique through Visual Programming Application as Learning Media with Fuzzy Rating

    Science.gov (United States)

    Buditjahjanto, I. G. P. Asto; Nurlaela, Luthfiyah; Ekohariadi; Riduwan, Mochamad

    2017-01-01

    Programming technique is one of the subjects at Vocational High School in Indonesia. This subject contains theory and application of programming utilizing Visual Programming. Students experience some difficulties to learn textual learning. Therefore, it is necessary to develop media as a tool to transfer learning materials. The objectives of this…

  13. High Rates of Psychiatric Disorders and Below Normal Mental Capacity Associated With Spastic Peroneal Flatfoot: A New Relationship.

    Science.gov (United States)

    Kılıçoğlu, Önder İsmet; Salduz, Ahmet; Birişik, Fevzi; Bilgili, Fuat; Polat, Gökhan; Kaya, İlyas; Süleyman, Funda; Coşkun, Murat

    Spastic peroneal flatfoot (SPFF) is a rare hindfoot pathology usually seen in the adolescent age group that is characterized by painful spasms in the peroneal muscles. We have clinically observed that patients with SPFF also have some behavioral and emotional difficulties and problems in their academic achievements. Because of these observations, we investigated the prevalence and patterns of psychiatric disorders and intellectual disability among young subjects with SPFF. Our cohort consisted of 16 patients with SPFF. Their mean age at presentation was 21 (range 13 to 31) years. Only 6 patients had a tarsal coalition as an underlying condition. The psychometric evaluation was conducted using validated instruments (Wechsler Intelligence Scale for Children-revised form, Stanford Binet intelligence quotient [IQ] test, and Cattell IQ test). Psychiatric disorders were assessed using a semistructured diagnostic instrument (Schedule for Affective Disorders and Schizophrenia for School Age Children Present and Lifetime Version). The testers and psychiatrists were unaware of the orthopedic condition and the preliminary psychiatric diagnoses. The ethical committee approved the study protocol. The mean follow-up period was 41 (range 12 to 97) months. The mean IQ score of the patients was 75.1 ± 17.9 (range 52 to 107). Compared with the general population, the rate of intellectual disability was significantly greater (p = .0001) and the rate of normal intelligence significantly lower (p = .0015) in our patient group. Furthermore, according to the community schooling ratio, our cohort also had lower junior high and secondary education rates compared with the general population. The rate of most psychiatric disorders diagnosed in the SPFF patients was greater than that in the normal population. The most commonly identified psychiatric disorders were social phobia and attention deficit and hyperactivity disorder (75%). Timely interventions of the psychosocial and

  14. SU-F-J-45: Sparing Normal Tissue with Ultra-High Dose Rate in Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Y [DCH Reg. Medical Center, Tuscaloosa, AL (United States)

    2016-06-15

    Purpose: To spare normal tissue by reducing the location uncertainty of a moving target, we proposed an ultra-high dose rate system and evaluated. Methods: High energy electrons generated with a linear accelerator were injected into a storage ring to be accumulated. The number of the electrons in the ring was determined based on the prescribed radiation dose. The dose was delivered within a millisecond, when an online imaging system found that the target was in the position that was consistent with that in a treatment plan. In such a short time period, the displacement of the target was negligible. The margin added to the clinical target volume (CTV) could be reduced that was evaluated by comparing of volumes between CTV and ITV in 14 cases of lung stereotactic body radiation therapy (SBRT) treatments. A design of the ultra-high dose rate system was evaluated based clinical needs and the recent developments of low energy (a few MeV) electron storage ring. Results: This design of ultra-high dose rate system was feasible based on the techniques currently available. The reduction of a target volume was significant by reducing the margin that accounted the motion of the target. ∼50% volume reduction of the internal target volume (ITV) could be achieved in lung SBRT treatments. Conclusion: With this innovation of ultra-high dose rate system, the margin of target is able to be significantly reduced. It will reduce treatment time of gating and allow precisely specified gating window to improve the accuracy of dose delivering.

  15. Efficient Photometry In-Frame Calibration (EPIC) Gaussian Corrections for Automated Background Normalization of Rate-Tracked Satellite Imagery

    Science.gov (United States)

    Griesbach, J.; Wetterer, C.; Sydney, P.; Gerber, J.

    Photometric processing of non-resolved Electro-Optical (EO) images has commonly required the use of dark and flat calibration frames that are obtained to correct for charge coupled device (CCD) dark (thermal) noise and CCD quantum efficiency/optical path vignetting effects respectively. It is necessary to account/calibrate for these effects so that the brightness of objects of interest (e.g. stars or resident space objects (RSOs)) may be measured in a consistent manner across the CCD field of view. Detected objects typically require further calibration using aperture photometry to compensate for sky background (shot noise). For this, annuluses are measured around each detected object whose contained pixels are used to estimate an average background level that is subtracted from the detected pixel measurements. In a new photometric calibration software tool developed for AFRL/RD, called Efficient Photometry In-Frame Calibration (EPIC), an automated background normalization technique is proposed that eliminates the requirement to capture dark and flat calibration images. The proposed technique simultaneously corrects for dark noise, shot noise, and CCD quantum efficiency/optical path vignetting effects. With this, a constant detection threshold may be applied for constant false alarm rate (CFAR) object detection without the need for aperture photometry corrections. The detected pixels may be simply summed (without further correction) for an accurate instrumental magnitude estimate. The noise distribution associated with each pixel is assumed to be sampled from a Poisson distribution. Since Poisson distributed data closely resembles Gaussian data for parameterized means greater than 10, the data may be corrected by applying bias subtraction and standard-deviation division. EPIC performs automated background normalization on rate-tracked satellite images using the following technique. A deck of approximately 50-100 images is combined by performing an independent median

  16. Life span prediction from the rate of age-related DNA demethylation in normal and cancer cell lines.

    Science.gov (United States)

    Mazin, A L

    1995-01-01

    A method has been proposed for the Hayflick Limit prediction by the analysis of the 5-methylcytosine content in DNA at earlier and later cell passages. The following facts were used as the basis of the method: (i) the rate of m5C loss from DNA remains approximately constant during cell divisions and it does not depend on the cell donor age; (ii) this rate is inversely proportional to the Hayflick Limit as well as to the life span of cell donor species; (iii) the period corresponded to loss of all m5C residues from the genome coincides with or somewhat exceeds the Hayflick Limit of normal cells. The prognosis of the Hayflick Limit has usually been found in good agreement with the experimental evidences for various human, hamster, and mouse cell lines. The method proposed may be used for early detection of precrisis and cancer cells. The age-related m5C loss may result from accumulation of the m5C-->T+C transitions occurring with DNA methylation in every cell division.

  17. Situated learning theory: adding rate and complexity effects via Kauffman's NK model.

    Science.gov (United States)

    Yuan, Yu; McKelvey, Bill

    2004-01-01

    For many firms, producing information, knowledge, and enhancing learning capability have become the primary basis of competitive advantage. A review of organizational learning theory identifies two approaches: (1) those that treat symbolic information processing as fundamental to learning, and (2) those that view the situated nature of cognition as fundamental. After noting that the former is inadequate because it focuses primarily on behavioral and cognitive aspects of individual learning, this paper argues the importance of studying learning as interactions among people in the context of their environment. It contributes to organizational learning in three ways. First, it argues that situated learning theory is to be preferred over traditional behavioral and cognitive learning theories, because it treats organizations as complex adaptive systems rather than mere information processors. Second, it adds rate and nonlinear learning effects. Third, following model-centered epistemology, it uses an agent-based computational model, in particular a "humanized" version of Kauffman's NK model, to study the situated nature of learning. Using simulation results, we test eight hypotheses extending situated learning theory in new directions. The paper ends with a discussion of possible extensions of the current study to better address key issues in situated learning.

  18. Figurative and Operative Bases of Memory: Evidence from Normal and Learning Disabled Child.

    Science.gov (United States)

    Trepanier, Mary L.; Liben, Lynn S.

    A set of studies investigated the relative importance of operative schemes and figurative (rote) memory. In Study I, 60 concrete operational children from grades 1-4 were asked to reconstruct two types of stimuli from memory. In order to separate the effects of operative and figurative skill use, learning disabled children with poor figurative…

  19. New Treatments for Autism: Effects of a Gluten-Free Diet on Rate of Learning.

    Science.gov (United States)

    Grace, Jennifer B.; Velez, Denise M.; Chambliss, Catherine

    This study assessed the effects of a gluten-free diet over one year on learning patterns in three autistic children (ages 5 to 8) participating in an applied behavioral analysis program. Rates of learning for five behavioral targets 3 months, 6 months, 9 months, and 12 months after the start of the diet were compared using a within-subjects…

  20. Automatic learning rate adjustment for self-supervising autonomous robot control

    Science.gov (United States)

    Arras, Michael K.; Protzel, Peter W.; Palumbo, Daniel L.

    1992-01-01

    Described is an application in which an Artificial Neural Network (ANN) controls the positioning of a robot arm with five degrees of freedom by using visual feedback provided by two cameras. This application and the specific ANN model, local liner maps, are based on the work of Ritter, Martinetz, and Schulten. We extended their approach by generating a filtered, average positioning error from the continuous camera feedback and by coupling the learning rate to this error. When the network learns to position the arm, the positioning error decreases and so does the learning rate until the system stabilizes at a minimum error and learning rate. This abolishes the need for a predetermined cooling schedule. The automatic cooling procedure results in a closed loop control with no distinction between a learning phase and a production phase. If the positioning error suddenly starts to increase due to an internal failure such as a broken joint, or an environmental change such as a camera moving, the learning rate increases accordingly. Thus, learning is automatically activated and the network adapts to the new condition after which the error decreases again and learning is 'shut off'. The automatic cooling is therefore a prerequisite for the autonomy and the fault tolerance of the system.

  1. Reliability of the Motor Learning Strategy Rating Instrument for Children and Youth with Acquired Brain Injury

    Science.gov (United States)

    Kamath, Trishna; Pfeifer, Megan; Banerjee-Guenette, Priyanka; Hunter, Theresa; Ito, Julia; Salbach, Nancy M.; Wright, Virginia; Levac, Danielle

    2012-01-01

    Purpose: To evaluate reliability and feasibility of the Motor Learning Strategy Rating Instrument (MLSRI) in children with acquired brain injury (ABI). The MLSRI quantifies the extent to which motor learning strategies (MLS) are used within physiotherapy (PT) interventions. Methods: PT sessions conducted by ABI team physiotherapists with a…

  2. Effects of Learning Experience on Forgetting Rates of Item and Associative Memories

    Science.gov (United States)

    Yang, Jiongjiong; Zhan, Lexia; Wang, Yingying; Du, Xiaoya; Zhou, Wenxi; Ning, Xueling; Sun, Qing; Moscovitch, Morris

    2016-01-01

    Are associative memories forgotten more quickly than item memories, and does the level of original learning differentially influence forgetting rates? In this study, we addressed these questions by having participants learn single words and word pairs once (Experiment 1), three times (Experiment 2), and six times (Experiment 3) in a massed…

  3. Punishing the Vulnerable: Exploring Suspension Rates for Students with Learning Disabilities

    Science.gov (United States)

    Brobbey, Gordon

    2018-01-01

    Students with learning disabilities are suspended at disproportionate rates in schools. Although research has shown the ineffectiveness of suspension as a disciplinary tool, school administrators continue to use it to combat behavior infractions. This column presents a review of the literature on suspension for students with learning disabilities,…

  4. Erythropoietin improves place learning in fimbria-fornix-transected rats and modifies the search pattern of normal rats

    DEFF Research Database (Denmark)

    Mogensen, Jesper; Miskowiak, Kamilla; Sørensen, Thomas Alrik

    2004-01-01

    administration of EPO significantly improves the posttraumatic functional recovery of the presently studied place learning task after transections of the fimbria-fornix. Additionally, administration of EPO influences the strategy, although not quality, of task solution in normal (sham-operated) rats.......The acquisition of a water-maze-based allocentric place learning task was studied in four groups of rats: two groups subjected to bilateral transections of the fimbria-fornix and two groups undergoing a sham control operation. At the moment of surgery all animals were given one systemic......-associated impairment. The two sham-operated groups did not differ with respect to the proficiency of task acquisition. But administration of EPO to intact animals caused a significant modification of swim patterns-apparently reflecting a somewhat modified strategy of task solution. It is concluded that systemic...

  5. Global Bi-ventricular endocardial distribution of activation rate during long duration ventricular fibrillation in normal and heart failure canines.

    Science.gov (United States)

    Luo, Qingzhi; Jin, Qi; Zhang, Ning; Han, Yanxin; Wang, Yilong; Huang, Shangwei; Lin, Changjian; Ling, Tianyou; Chen, Kang; Pan, Wenqi; Wu, Liqun

    2017-04-13

    The objective of this study was to detect differences in the distribution of the left and right ventricle (LV & RV) activation rate (AR) during short-duration ventricular fibrillation (SDVF, 1 min) in normal and heart failure (HF) canine hearts. Ventricular fibrillation (VF) was electrically induced in six healthy dogs (control group) and six dogs with right ventricular pacing-induced congestive HF (HF group). Two 64-electrode basket catheters deployed in the LV and RV were used for global endocardium electrical mapping. The AR of VF was estimated by fast Fourier transform analysis from each electrode. In the control group, the LV was activated faster than the RV in the first 20 s, after which there was no detectable difference in the AR between them. When analyzing the distribution of the AR within the bi-ventricles at 3 min of LDVF, the posterior LV was activated fastest, while the anterior was slowest. In the HF group, a detectable AR gradient existed between the two ventricles within 3 min of VF, with the LV activating more quickly than the RV. When analyzing the distribution of the AR within the bi-ventricles at 3 min of LDVF, the septum of the LV was activated fastest, while the anterior was activated slowest. A global bi-ventricular endocardial AR gradient existed within the first 20 s of VF but disappeared in the LDVF in healthy hearts. However, the AR gradient was always observed in both SDVF and LDVF in HF hearts. The findings of this study suggest that LDVF in HF hearts can be maintained differently from normal hearts, which accordingly should lead to the development of different management strategies for LDVF resuscitation.

  6. Classifying depression patients and normal subjects using machine learning techniques and nonlinear features from EEG signal.

    Science.gov (United States)

    Hosseinifard, Behshad; Moradi, Mohammad Hassan; Rostami, Reza

    2013-03-01

    Diagnosing depression in the early curable stages is very important and may even save the life of a patient. In this paper, we study nonlinear analysis of EEG signal for discriminating depression patients and normal controls. Forty-five unmedicated depressed patients and 45 normal subjects were participated in this study. Power of four EEG bands and four nonlinear features including detrended fluctuation analysis (DFA), higuchi fractal, correlation dimension and lyapunov exponent were extracted from EEG signal. For discriminating the two groups, k-nearest neighbor, linear discriminant analysis and logistic regression as the classifiers are then used. Highest classification accuracy of 83.3% is obtained by correlation dimension and LR classifier among other nonlinear features. For further improvement, all nonlinear features are combined and applied to classifiers. A classification accuracy of 90% is achieved by all nonlinear features and LR classifier. In all experiments, genetic algorithm is employed to select the most important features. The proposed technique is compared and contrasted with the other reported methods and it is demonstrated that by combining nonlinear features, the performance is enhanced. This study shows that nonlinear analysis of EEG can be a useful method for discriminating depressed patients and normal subjects. It is suggested that this analysis may be a complementary tool to help psychiatrists for diagnosing depressed patients. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  7. A Comparison of Evaluation Practices Based on E-Learning and Mobile Learning Delivery Rates

    Science.gov (United States)

    Marshall, James

    2018-01-01

    Learning and performance professionals are increasingly pressed to measure the results of their learning program design efforts, and ultimately prove their worth. However, evaluation efforts are often limited to measuring participant reaction. This study sought to quantify evaluation practices in organizations and investigate how the use of…

  8. Interpersonal Complementarity – Self-rated Behavior by Normal and Antisocial Adolescents with a Liked and Disliked Peer

    Directory of Open Access Journals (Sweden)

    Camilla Hakelind

    2007-12-01

    Full Text Available The principle of complementarity in interpersonal theory and the SASB model (Structural Analysis of Social Behavior as developed by Benjamin (1974 were used to study how adolescents in a normal group of 60 adolescents and a group of 42 adolescents with severe behavioural problems rated that they usually behaved in relation to a liked and disliked peer. The peer’s behaviour varied in a systematic way on the dimensions of affiliation and dominance. Complementary behavior was defined as the same behaviour from peer and self and anticomplementarity was defined as opposite behaviour from self in relation the peer’s behavior. Consistent over the two groups complementarity and anticomplementarity were influenced by both the peer’s behaviour and type of relationship with the peer. Friendly behaviour from a liked peer evoked much more complementary friendly behaviour compared to a disliked peer who with the same behaviour evoked almost as much anticomplementary hostile behaviour as complementary friendly behaviour. Hostile behaviour from a disliked peer evoked much more complementary hostile behaviour compared to a liked peer with the same kind of behavior. Autonomy granting from a liked peer evoked more complementary autonomous behaviour compared to a disliked peer. Differences between the two groups were small and only in relation with a disliked peer. The results were discussed in terms of interpersonal theory and the principle of complementarity with focus on kind of relationship.

  9. Late change of normal tissue treated either by high dose rate or low dose rate interstitial brachytherapy. A retrospective comparative study on oral and oropharyngeal mucosa

    International Nuclear Information System (INIS)

    Nose, Takayuki; Koizumi, Masahiko; Nishiyama, Kinji; Inoue, Toshihiko

    2002-01-01

    The purpose of this study was to compare late changes of normal tissue treated either by high dose rate (HDR) or low dose rate (LDR) interstitial brachytherapy. For HDR group, 22 oropharynx cancer patients who were treated by HDR Ir-192 interstitial brachytherapy with/without external beam radiotherapy in Osaka (Osaka Medical Center for Cancer and Cardiovascular Diseases and Osaka University Hospital) during June 1994 through April 2000 and came to the follow-up clinics during July 2000 through December 2000 were studied. For LDR group, 26 oropharynx cancer patients who were treated by LDR Ir-192 interstitial brachytherapy with/without external beam radiotherapy in Nancy (Centre Alexis Vautrin) during February 1989 through July 1998 and came to the follow-up clinics during April 1999 through July 1999 were studied. The standard HDR schedules were 54 Gy/9 fr/5-6 days for monotherapy and 18-24 Gy/3-4 fr/2-3 days following 45 Gy external beam radiotherapy. The standard LDR schedules were 65 Gy/5-6 days for monotherapy and 15-25 Gy/2-3 days following 50 Gy external beam radiotherapy. For evaluation of the late changes, we scored the mucosal and muscular changes inside the treated volume using the modified Dische score system and the RTOG/EORTC late radiation morbidity scoring scheme. For 6 items of the modified Dische score system, no significant difference was found between HDR and LDR groups. For the remaining 2 items (pallor, mobility impairment of faucial pillars), LDR group showed higher scores (p=0.010, 0.002). LDR group showed a trend toward higher scores for the RTOG/EORTC scheme (p=0.059). Some predict late effects by HDR interstitial brachytherapy to be severer than by LDR because no dose-rate effects can be expected. Our study, however, showed at least equivalent or even milder late changes by HDR. Appropriate fractionation schedule and extra geometrical sparing effects by optimized dose distribution of HDR group might result in milder late changes. With our

  10. Predicting High Frequency Exchange Rates using Machine Learning

    OpenAIRE

    Palikuca, Aleksandar; Seidl,, Timo

    2016-01-01

    This thesis applies a committee of Artificial Neural Networks and Support Vector Machines on high-dimensional, high-frequency EUR/USD exchange rate data in an effort to predict directional market movements on up to a 60 second prediction horizon. The study shows that combining multiple classifiers into a committee produces improved precision relative to the best individual committee members and outperforms previously reported results. A trading simulation implementing the committee classifier...

  11. Intrauterine growth-restricted piglets have similar gastric emptying rates but lower rectal temperatures and altered blood values when compared with normal-weight piglets at birth

    DEFF Research Database (Denmark)

    Williams, Charlotte Amdi; Klarlund, M. V.; Pedersen, Janni Hales

    2016-01-01

    Intrauterine growth-restricted (IUGR) piglets have lower survival rates and are more likely to have empty stomachs 24 h after birth than normal piglets. Although hypoglycemia may result from low colostrum intake per se, it is not known if slow gastric emptying may be an additional risk factor...... that the gastric emptying rate and blood glucose would be lower in IUGR piglets. We investigated gastric emptying rates in normal and IUGR piglets and blood glucose and rectal temperatures at birth and after 15, 30, 60, and 120 min. In addition, blood parameters relevant for metabolism were studied. Forty......-eight piglets (24 normal and 24 IUGR) were classified at birth as either normal or IUGR on the basis of head morphology. Piglets were removed from the sow at birth before suckling, and birth weight was recorded. Pooled porcine colostrum was tube-fed to all piglets at 12 mL/kg BW as soon as possible after birth...

  12. Scenario analysis for estimating the learning rate of photovoltaic power generation based on learning curve theory in South Korea

    International Nuclear Information System (INIS)

    Hong, Sungjun; Chung, Yanghon; Woo, Chungwon

    2015-01-01

    South Korea, as the 9th largest energy consuming in 2013 and the 7th largest greenhouse gas emitting country in 2011, established ‘Low Carbon Green Growth’ as the national vision in 2008, and is announcing various active energy policies that are set to gain the attention of the world. In this paper, we estimated the decrease of photovoltaic power generation cost in Korea based on the learning curve theory. Photovoltaic energy is one of the leading renewable energy sources, and countries all over the world are currently expanding R and D, demonstration and deployment of photovoltaic technology. In order to estimate the learning rate of photovoltaic energy in Korea, both conventional 1FLC (one-factor learning curve), which considers only the cumulative power generation, and 2FLC, which also considers R and D investment were applied. The 1FLC analysis showed that the cost of power generation decreased by 3.1% as the cumulative power generation doubled. The 2FCL analysis presented that the cost decreases by 2.33% every time the cumulative photovoltaic power generation is doubled and by 5.13% every time R and D investment is doubled. Moreover, the effect of R and D investment on photovoltaic technology took after around 3 years, and the depreciation rate of R and D investment was around 20%. - Highlights: • We analyze the learning effects of photovoltaic energy technology in Korea. • In order to calculate the learning rate, we use 1FLC (one-factor learning curve) and 2FLC methods, respectively. • 1FLC method considers only the cumulative power generation. • 2FLC method considers both cumulative power generation and knowledge stock. • We analyze a variety of scenarios by time lag and depreciation rate of R and D investment

  13. Type I error rates of rare single nucleotide variants are inflated in tests of association with non-normally distributed traits using simple linear regression methods.

    Science.gov (United States)

    Schwantes-An, Tae-Hwi; Sung, Heejong; Sabourin, Jeremy A; Justice, Cristina M; Sorant, Alexa J M; Wilson, Alexander F

    2016-01-01

    In this study, the effects of (a) the minor allele frequency of the single nucleotide variant (SNV), (b) the degree of departure from normality of the trait, and (c) the position of the SNVs on type I error rates were investigated in the Genetic Analysis Workshop (GAW) 19 whole exome sequence data. To test the distribution of the type I error rate, 5 simulated traits were considered: standard normal and gamma distributed traits; 2 transformed versions of the gamma trait (log 10 and rank-based inverse normal transformations); and trait Q1 provided by GAW 19. Each trait was tested with 313,340 SNVs. Tests of association were performed with simple linear regression and average type I error rates were determined for minor allele frequency classes. Rare SNVs (minor allele frequency < 0.05) showed inflated type I error rates for non-normally distributed traits that increased as the minor allele frequency decreased. The inflation of average type I error rates increased as the significance threshold decreased. Normally distributed traits did not show inflated type I error rates with respect to the minor allele frequency for rare SNVs. There was no consistent effect of transformation on the uniformity of the distribution of the location of SNVs with a type I error.

  14. Longitudinal Associations among Renal Urea Clearance-Corrected Normalized Protein Catabolic Rate, Serum Albumin, and Mortality in Patients on Hemodialysis.

    Science.gov (United States)

    Eriguchi, Rieko; Obi, Yoshitsugu; Streja, Elani; Tortorici, Amanda R; Rhee, Connie M; Soohoo, Melissa; Kim, Taehee; Kovesdy, Csaba P; Kalantar-Zadeh, Kamyar

    2017-07-07

    There are inconsistent reports on the association of dietary protein intake with serum albumin and outcomes among patients on hemodialysis. Using a new normalized protein catabolic rate (nPCR) variable accounting for residual renal urea clearance, we hypothesized that higher baseline nPCR and rise in nPCR would be associated with higher serum albumin and better survival among incident hemodialysis patients. Among 36,757 incident hemodialysis patients in a large United States dialysis organization, we examined baseline and change in renal urea clearance-corrected nPCR as a protein intake surrogate and modeled their associations with serum albumin and mortality over 5 years (1/2007-12/2011). Median nPCRs with and without accounting for renal urea clearance at baseline were 0.94 and 0.78 g/kg per day, respectively (median within-patient difference, 0.14 [interquartile range, 0.07-0.23] g/kg per day). During a median follow-up period of 1.4 years, 8481 deaths were observed. Baseline renal urea clearance-corrected nPCR was associated with higher serum albumin and lower mortality in the fully adjusted model ( P trend urea clearance-corrected nPCR during the first 6 months was also associated with attaining high serum albumin (≥3.8 g/dl) and lower mortality ( P trend urea clearance, higher levels of renal urea clearance-corrected nPCR consistently showed lower mortality risk. Among incident hemodialysis patients, higher dietary protein intake represented by nPCR and its changes over time appear to be associated with increased serum albumin levels and greater survival. nPCR may be underestimated when not accounting for renal urea clearance. Compared with the conventional nPCR, renal urea clearance-corrected nPCR may be a better marker of mortality. Copyright © 2017 by the American Society of Nephrology.

  15. The effect of puberty on fat oxidation rates during exercise in overweight and normal-weight girls.

    Science.gov (United States)

    Chu, L; Riddell, M C; Schneiderman, J E; McCrindle, B W; Hamilton, J K

    2014-01-01

    Excess weight is often associated with insulin resistance (IR) and may disrupt fat oxidation during exercise. This effect is further modified by puberty. While studies have shown that maximal fat oxidation rates (FOR) during exercise decrease with puberty in normal-weight (NW) and overweight (OW) boys, the effect of puberty in NW and OW girls is unclear. Thirty-three NW and OW girls ages 8-18 yr old completed a peak aerobic capacity test on a cycle ergometer. FOR were calculated during progressive submaximal exercise. Body composition and Tanner stage were determined. For each participant, a best-fit polynomial curve was constructed using fat oxidation vs. exercise intensity to estimate max FOR. In a subset of the girls, IR derived from an oral glucose tolerance test (n = 20), and leptin and adiponectin levels (n = 11) were assessed in relation to FOR. NW pre-early pubertal girls had higher max FOR [6.9 ± 1.4 mg·kg fat free mass (FFM)(-1)·min(-1)] than NW mid-late pubertal girls (2.2 ± 0.9 mg·kg FFM(-1)·min(-1)) (P = 0.002), OW pre-early pubertal girls (3.8 ± 2.1 mg·kg FFM(-1)·min(-1)), and OW mid-late pubertal girls (3.3 ± 0.9 mg·kg FFM(-1)·min(-1)) (P puberty; however, this decrease associated with puberty was blunted in OW girls due to lower FOR in pre-early puberty. The presence of IR due to obesity potentially masks the effect of puberty on FOR during exercise in girls.

  16. Progressive epicardial coronary blood flow reduction fails to produce ST-segment depression at normal heart rates.

    Science.gov (United States)

    de Chantal, Marilyn; Diodati, Jean G; Nasmith, James B; Amyot, Robert; LeBlanc, A Robert; Schampaert, Erick; Pharand, Chantal

    2006-12-01

    ST-segment depression is commonly seen in patients with acute coronary syndromes. Most authors have attributed it to transient reductions in coronary blood flow due to nonocclusive thrombus formation on a disrupted atherosclerotic plaque and dynamic focal vasospasm at the site of coronary artery stenosis. However, ST-segment depression was never reproduced in classic animal models of coronary stenosis without the presence of tachycardia. We hypothesized that ST-segment depression occurring during acute coronary syndromes is not entirely explained by changes in epicardial coronary artery resistance and thus evaluated the effect of a slow, progressive epicardial coronary artery occlusion on the ECG and regional myocardial blood flow in anesthetized pigs. Slow, progressive occlusion over 72 min (SD 27) of the left anterior descending coronary artery in 20 anesthetized pigs led to a 90% decrease in coronary blood flow and the development of ST-segment elevation associated with homogeneous and transmural myocardial blood flow reductions, confirmed by microspheres and myocardial contrast echocardiography. ST-segment depression was not observed in any ECG lead before the development of ST-segment elevation. At normal heart rates, progressive epicardial stenosis of a coronary artery results in myocardial ischemia associated with homogeneous, transmural reduction in regional myocardial blood flow and ST-segment elevation, without preceding ST-segment depression. Thus, in coronary syndromes with ST-segment depression and predominant subendocardial ischemia, factors other than mere increases in epicardial coronary resistance must be invoked to explain the heterogeneous parietal distribution of flow and associated ECG changes.

  17. Caudate nucleus reactivity predicts perceptual learning rate for visual feature conjunctions.

    Science.gov (United States)

    Reavis, Eric A; Frank, Sebastian M; Tse, Peter U

    2015-04-15

    Useful information in the visual environment is often contained in specific conjunctions of visual features (e.g., color and shape). The ability to quickly and accurately process such conjunctions can be learned. However, the neural mechanisms responsible for such learning remain largely unknown. It has been suggested that some forms of visual learning might involve the dopaminergic neuromodulatory system (Roelfsema et al., 2010; Seitz and Watanabe, 2005), but this hypothesis has not yet been directly tested. Here we test the hypothesis that learning visual feature conjunctions involves the dopaminergic system, using functional neuroimaging, genetic assays, and behavioral testing techniques. We use a correlative approach to evaluate potential associations between individual differences in visual feature conjunction learning rate and individual differences in dopaminergic function as indexed by neuroimaging and genetic markers. We find a significant correlation between activity in the caudate nucleus (a component of the dopaminergic system connected to visual areas of the brain) and visual feature conjunction learning rate. Specifically, individuals who showed a larger difference in activity between positive and negative feedback on an unrelated cognitive task, indicative of a more reactive dopaminergic system, learned visual feature conjunctions more quickly than those who showed a smaller activity difference. This finding supports the hypothesis that the dopaminergic system is involved in visual learning, and suggests that visual feature conjunction learning could be closely related to associative learning. However, no significant, reliable correlations were found between feature conjunction learning and genotype or dopaminergic activity in any other regions of interest. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Is "Learning" episodic memory? Distinct cognitive and neuroanatomic correlates of immediate recall during learning trials in neurologically normal aging and neurodegenerative cohorts.

    Science.gov (United States)

    Casaletto, K B; Marx, G; Dutt, S; Neuhaus, J; Saloner, R; Kritikos, L; Miller, B; Kramer, J H

    2017-07-28

    Although commonly interpreted as a marker of episodic memory during neuropsychological exams, relatively little is known regarding the neurobehavior of "total learning" immediate recall scores. Medial temporal lobes are clearly associated with delayed recall performances, yet immediate recall may necessitate networks beyond traditional episodic memory. We aimed to operationalize cognitive and neuroanatomic correlates of total immediate recall in several aging syndromes. Demographically-matched neurologically normal adults (n=91), individuals with Alzheimer's disease (n=566), logopenic variant primary progressive aphasia (PPA) (n=34), behavioral variant frontotemporal dementia (n=97), semantic variant PPA (n=71), or nonfluent/agrammatic variant PPA (n=39) completed a neurocognitive battery, including the CVLT-Short Form trials 1-4 Total Immediate Recall; a majority subset also completed a brain MRI. Regressions covaried for age and sex, and MMSE in cognitive and total intracranial volume in neuroanatomic models. Neurologically normal adults demonstrated a heterogeneous pattern of cognitive associations with total immediate recall (executive, speed, delayed recall), such that no singular cognitive or neuroanatomic correlate uniquely predicted performance. Within the clinical cohorts, there were syndrome-specific cognitive and neural associations with total immediate recall; e.g., semantic processing was the strongest cognitive correlate in svPPA (partial r=0.41), while frontal volumes was the only meaningful neural correlate in bvFTD (partial r=0.20). Medial temporal lobes were not independently associated with total immediate recall in any group (ps>0.05). Multiple neurobehavioral systems are associated with "total learning" immediate recall scores that importantly differ across distinct clinical syndromes. Conventional memory networks may not be sufficient or even importantly contribute to total immediate recall in many syndromes. Interpreting learning scores as

  19. Comparison of the predictions of the LQ and CRE models for normal tissue damage due to biologically targeted radiotherapy with exponentially decaying dose rates

    International Nuclear Information System (INIS)

    O'Donoghue, J.A.; West of Schotland Health Boards, Glasgow

    1989-01-01

    For biologically targeted radiotherapy organ dose rates may be complex functions of time, related to the biodistribution kinetics of the delivery vehicle and radiolabel. The simples situation is where dose rates are exponentially decaying functions of time. Two normal tissue isoeffect models enable the effects of exponentially decaying dose rates to be addressed. These are the extension of the linear-quadratic model and the cumulative radiation effect model. This communication will compare the predictions of these models. (author). 14 refs.; 1 fig

  20. PBODL : Parallel Bayesian Online Deep Learning for Click-Through Rate Prediction in Tencent Advertising System

    OpenAIRE

    Liu, Xun; Xue, Wei; Xiao, Lei; Zhang, Bo

    2017-01-01

    We describe a parallel bayesian online deep learning framework (PBODL) for click-through rate (CTR) prediction within today's Tencent advertising system, which provides quick and accurate learning of user preferences. We first explain the framework with a deep probit regression model, which is trained with probabilistic back-propagation in the mode of assumed Gaussian density filtering. Then we extend the model family to a variety of bayesian online models with increasing feature embedding ca...

  1. Attention Cueing and Activity Equally Reduce False Alarm Rate in Visual-Auditory Associative Learning through Improving Memory.

    Science.gov (United States)

    Nikouei Mahani, Mohammad-Ali; Haghgoo, Hojjat Allah; Azizi, Solmaz; Nili Ahmadabadi, Majid

    2016-01-01

    In our daily life, we continually exploit already learned multisensory associations and form new ones when facing novel situations. Improving our associative learning results in higher cognitive capabilities. We experimentally and computationally studied the learning performance of healthy subjects in a visual-auditory sensory associative learning task across active learning, attention cueing learning, and passive learning modes. According to our results, the learning mode had no significant effect on learning association of congruent pairs. In addition, subjects' performance in learning congruent samples was not correlated with their vigilance score. Nevertheless, vigilance score was significantly correlated with the learning performance of the non-congruent pairs. Moreover, in the last block of the passive learning mode, subjects significantly made more mistakes in taking non-congruent pairs as associated and consciously reported lower confidence. These results indicate that attention and activity equally enhanced visual-auditory associative learning for non-congruent pairs, while false alarm rate in the passive learning mode did not decrease after the second block. We investigated the cause of higher false alarm rate in the passive learning mode by using a computational model, composed of a reinforcement learning module and a memory-decay module. The results suggest that the higher rate of memory decay is the source of making more mistakes and reporting lower confidence in non-congruent pairs in the passive learning mode.

  2. The Effect of Learning Modality and Auditory Feedback on Word Memory: Cochlear-Implanted versus Normal-Hearing Adults.

    Science.gov (United States)

    Taitelbaum-Swead, Riki; Icht, Michal; Mama, Yaniv

    2017-03-01

    In recent years, the effect of cognitive abilities on the achievements of cochlear implant (CI) users has been evaluated. Some studies have suggested that gaps between CI users and normal-hearing (NH) peers in cognitive tasks are modality specific, and occur only in auditory tasks. The present study focused on the effect of learning modality (auditory, visual) and auditory feedback on word memory in young adults who were prelingually deafened and received CIs before the age of 5 yr, and their NH peers. A production effect (PE) paradigm was used, in which participants learned familiar study words by vocal production (saying aloud) or by no-production (silent reading or listening). Words were presented (1) in the visual modality (written) and (2) in the auditory modality (heard). CI users performed the visual condition twice-once with the implant ON and once with it OFF. All conditions were followed by free recall tests. Twelve young adults, long-term CI users, implanted between ages 1.7 and 4.5 yr, and who showed ≥50% in monosyllabic consonant-vowel-consonant open-set test with their implants were enrolled. A group of 14 age-matched NH young adults served as the comparison group. For each condition, we calculated the proportion of study words recalled. Mixed-measures analysis of variances were carried out with group (NH, CI) as a between-subjects variable, and learning condition (aloud or silent reading) as a within-subject variable. Following this, paired sample t tests were used to evaluate the PE size (differences between aloud and silent words) and overall recall ratios (aloud and silent words combined) in each of the learning conditions. With visual word presentation, young adults with CIs (regardless of implant status CI-ON or CI-OFF), showed comparable memory performance (and a similar PE) to NH peers. However, with auditory presentation, young adults with CIs showed poorer memory for nonproduced words (hence a larger PE) relative to their NH peers. The

  3. Interacting Effects of Instructions and Presentation Rate on Visual Statistical Learning

    Directory of Open Access Journals (Sweden)

    Julie eBertels

    2015-11-01

    Full Text Available The statistical regularities of a sequence of visual shapes can be learned incidentally. Arciuli et al. (2014 recently argued that intentional instructions only improve learning at slow presentation rates as they favor the use of explicit strategies. The aim of the present study was (1 to test this assumption directly by investigating how instructions (incidental vs. intentional and presentation rate (fast vs. slow affect the acquisition of knowledge and (2 to examine how these factors influence the conscious vs. unconscious nature of the knowledge acquired. To this aim, we exposed participants to four triplets of shapes, presented sequentially in a pseudo-random order, and assessed their degree of learning in a subsequent completion task that integrated confidence judgments. Supporting Arciuli et al.’s claim, participant performance only benefited from intentional instructions at slow presentation rates. Moreover, informing participants beforehand about the existence of statistical regularities increased their explicit knowledge of the sequences, an effect that was not modulated by presentation speed. These results support that, although visual statistical learning can take place incidentally and, to some extent, outside conscious awareness, factors such as presentation rate and prior knowledge can boost learning of these regularities, presumably by favoring the acquisition of explicit knowledge.

  4. Resting-state qEEG predicts rate of second language learning in adults.

    Science.gov (United States)

    Prat, Chantel S; Yamasaki, Brianna L; Kluender, Reina A; Stocco, Andrea

    2016-01-01

    Understanding the neurobiological basis of individual differences in second language acquisition (SLA) is important for research on bilingualism, learning, and neural plasticity. The current study used quantitative electroencephalography (qEEG) to predict SLA in college-aged individuals. Baseline, eyes-closed resting-state qEEG was used to predict language learning rate during eight weeks of French exposure using an immersive, virtual scenario software. Individual qEEG indices predicted up to 60% of the variability in SLA, whereas behavioral indices of fluid intelligence, executive functioning, and working-memory capacity were not correlated with learning rate. Specifically, power in beta and low-gamma frequency ranges over right temporoparietal regions were strongly positively correlated with SLA. These results highlight the utility of resting-state EEG for studying the neurobiological basis of SLA in a relatively construct-free, paradigm-independent manner. Published by Elsevier Inc.

  5. Development of a student rating scale to evaluate teachers' competencies for facilitating reflective learning

    NARCIS (Netherlands)

    Schaub-de Jong, Mirabelle A.; Schonrock-Adema, Johanna; Dekker, Hanke; Verkerk, Marian; Cohen-Schotanus, Janke

    Context Teaching students in reflection calls for specific teacher competencies. We developed and validated a rating scale focusing on Student perceptions of their Teachers' competencies to Encourage Reflective Learning in small Groups (STERLinG). Methods We applied an iterative procedure to reduce

  6. The interchangeability of learning rate and gain in backpropagation neural networks

    NARCIS (Netherlands)

    Thimm, G.; Moerland, P.; Fiesler, E.

    1996-01-01

    The backpropagation algorithm is widely used for training multilayer neural networks. In this publication the gain of its activation function(s) is investigated. In specific, it is proven that changing the gain of the activation function is equivalent to changing the learning rate and the weights.

  7. Inhibiting effect of plasma from normal and tumour bearing mice on the mitotic rate of regenerating liver.

    Science.gov (United States)

    Echave Llanos, J M; Moreno, F R; Badrán, A F

    1986-01-01

    Plasma from normal mice and from mice bearing the ES2 transplantable malignant tumour was injected intraperitoneally at a dose of 0.01 ml/g body weight in partially hepatectomized mice. Control animals were injected with a solution of sodium citrate in saline. The recipients were killed at the first (14:00 hours/48 h). These times are the time of day and the number of h after partial hepatectomy and second (14:00 hours/72 h) peak times after partial hepatectomy. The number of colchicine metaphases per 1000 nuclei was determined for hepatocytes and litoral cells. A different effect was obtained with plasma from tumour-bearing compared with normal mice. Plasma from both sources when injected 26 h after partial hepatectomy (16:00 hours/26 h) inhibited the mitotic activity of hepatocytes at the next peak of regenerative activity (14:00 hours/48 h). The plasma from tumour-bearing mice also inhibited the peak on the following day (14:00 hours/72 h), whereas plasma from normal mice had no inhibitory effect and, indeed, a compensatory wave was observed at this time. Furthermore, plasma from tumour-bearing mice also showed an inhibitory effect at the first peak (14:00 hours/48 h) when injected at the time of partial hepatectomy (14:00 hours/00 h) or at 22 h before partial hepatectomy (16:00 hours/-22 h) whereas the injection of plasma from normal mice at these times had no inhibitory effect. In the litoral cells the injection of plasma from tumour-bearing mice made 22 h before hepatectomy (16:00 hours/-22 h) led to a stimulation of mitotic activity which was controlled at 14:00 hours/48 h.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Adaptive response to ionizing radiation in normal human skin fibroblasts. Enhancement of DNA repair rate and modulation of gene expression

    International Nuclear Information System (INIS)

    Toledo, S.M. de; Mitchel, R.E.J.; Azzam, E.; Ottawa Univ., ON; Raaphorst, G.P.

    1994-01-01

    Low doses and dose rates of ionizing radiation enhance the rate of DNA repair in human fibroblasts and protect the cells against radiation-induced micronucleus formation. Chronic exposures reduce the mRNA levels of the genes topoisomerase II and FACC-1 (Fanconi's anemia, group C). (authors). 11 refs., 1 tab., 2 figs

  9. Reflex control of heart rate in normal subjects in relation to age: a data base for cardiac vagal neuropathy

    NARCIS (Netherlands)

    Wieling, W.; van Brederode, J. F.; de Rijk, L. G.; Borst, C.; Dunning, A. J.

    1982-01-01

    We examined the heart rate changes induced by forced breathing and by standing up in 133 healthy subjects in the age range 10-65 years in order to establish a data base for studies on parasympathetic heart rate control in autonomic neuropathy. Test results declined with age. Log-transformation was

  10. Non-Constant Learning Rates in Retrospective Experience Curve Analyses and their Correlation to Deployment Programs

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Smith, Sarah J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sohn, Michael D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-07-16

    A key challenge for policy-makers and technology market forecasters is to estimate future technology costs and in particular the rate of cost reduction versus production volume. A related, critical question is what role should state and federal governments have in advancing energy efficient and renewable energy technologies? This work provides retrospective experience curves and learning rates for several energy-related technologies, each of which have a known history of federal and state deployment programs. We derive learning rates for eight technologies including energy efficient lighting technologies, stationary fuel cell systems, and residential solar photovoltaics, and provide an overview and timeline of historical deployment programs such as state and federal standards and state and national incentive programs for each technology. Piecewise linear regimes are observed in a range of technology experience curves, and public investments or deployment programs are found to be strongly correlated to an increase in learning rate across multiple technologies. A downward bend in the experience curve is found in 5 out of the 8 energy-related technologies presented here (electronic ballasts, magnetic ballasts, compact fluorescent lighting, general service fluorescent lighting, and the installed cost of solar PV). In each of the five downward-bending experience curves, we believe that an increase in the learning rate can be linked to deployment programs to some degree. This work sheds light on the endogenous versus exogenous contributions to technological innovation and highlights the impact of exogenous government sponsored deployment programs. This work can inform future policy investment direction and can shed light on market transformation and technology learning behavior.

  11. Resting heart rate variability predicts safety learning and fear extinction in an interoceptive fear conditioning paradigm.

    Directory of Open Access Journals (Sweden)

    Meike Pappens

    Full Text Available This study aimed to investigate whether interindividual differences in autonomic inhibitory control predict safety learning and fear extinction in an interoceptive fear conditioning paradigm. Data from a previously reported study (N = 40 were extended (N = 17 and re-analyzed to test whether healthy participants' resting heart rate variability (HRV - a proxy of cardiac vagal tone - predicts learning performance. The conditioned stimulus (CS was a slight sensation of breathlessness induced by a flow resistor, the unconditioned stimulus (US was an aversive short-lasting suffocation experience induced by a complete occlusion of the breathing circuitry. During acquisition, the paired group received 6 paired CS-US presentations; the control group received 6 explicitly unpaired CS-US presentations. In the extinction phase, both groups were exposed to 6 CS-only presentations. Measures included startle blink EMG, skin conductance responses (SCR and US-expectancy ratings. Resting HRV significantly predicted the startle blink EMG learning curves both during acquisition and extinction. In the unpaired group, higher levels of HRV at rest predicted safety learning to the CS during acquisition. In the paired group, higher levels of HRV were associated with better extinction. Our findings suggest that the strength or integrity of prefrontal inhibitory mechanisms involved in safety- and extinction learning can be indexed by HRV at rest.

  12. On diffusion processes with variable drift rates as models for decision making during learning

    International Nuclear Information System (INIS)

    Eckhoff, P; Holmes, P; Law, C; Connolly, P M; Gold, J I

    2008-01-01

    We investigate Ornstein-Uhlenbeck and diffusion processes with variable drift rates as models of evidence accumulation in a visual discrimination task. We derive power-law and exponential drift-rate models and characterize how parameters of these models affect the psychometric function describing performance accuracy as a function of stimulus strength and viewing time. We fit the models to psychophysical data from monkeys learning the task to identify parameters that best capture performance as it improves with training. The most informative parameter was the overall drift rate describing the signal-to-noise ratio of the sensory evidence used to form the decision, which increased steadily with training. In contrast, secondary parameters describing the time course of the drift during motion viewing did not exhibit steady trends. The results indicate that relatively simple versions of the diffusion model can fit behavior over the course of training, thereby giving a quantitative account of learning effects on the underlying decision process

  13. The effect of presentation rate on foreign-language vocabulary learning.

    Science.gov (United States)

    Zeelenberg, René; de Jonge, Mario; Tabbers, Huib K; Pecher, Diane

    2015-01-01

    The present study examined the effect of presentation rate on foreign-language vocabulary learning. Experiment 1 varied presentation rates from 1 s to 16 s per pair while keeping the total study time per pair constant. Speakers of English studied Dutch-English translation pairs (e.g., kikker-frog) for 16 × 1 s, 8 × 2 s, 4 × 4 s, 2 × 8 s, or 1 × 16 s. The results showed a nonmonotonic relationship between presentation rate and recall performance for both translation directions (Dutch → English and English → Dutch). Performance was best for intermediate presentation rates and dropped off for short (1 s) or long (16 s) presentation rates. Experiment 2 showed that the nonmonotonic relationship between presentation rate and recall performance was still present after a 1-day retention interval for both translation directions. Our results suggest that a presentation rate in the order of 4 s results in optimal learning of foreign-language vocabulary.

  14. Classification of Laser Induced Fluorescence Spectra from Normal and Malignant bladder tissues using Learning Vector Quantization Neural Network in Bladder Cancer Diagnosis

    DEFF Research Database (Denmark)

    Karemore, Gopal Raghunath; Mascarenhas, Kim Komal; Patil, Choudhary

    2008-01-01

    In the present work we discuss the potential of recently developed classification algorithm, Learning Vector Quantization (LVQ), for the analysis of Laser Induced Fluorescence (LIF) Spectra, recorded from normal and malignant bladder tissue samples. The algorithm is prototype based and inherently...

  15. Bannatyne-Recategorized WISC-R Patterns of Mentally Retarded, Learning Disabled, Normal, and Intellectually Superior Children: A Meta-Analysis.

    Science.gov (United States)

    Mueller, Horst H.; And Others

    1983-01-01

    Metaanalytical procedures examined the Wechsler Intelligence Scale-Revised subtest performance patterns of 36 samples of below average, normal average, learning disabled average, and above average IQ children from research. Relative patterning of WISC-R subtests as reflected in children's Bannatyne-recategorized performance profiles appeared to be…

  16. Characteristics and Activities of Teachers on Distance Learning Programs that Affect Their Ratings

    Directory of Open Access Journals (Sweden)

    Svetlana M. Stanišić Stojić

    2014-09-01

    Full Text Available This paper presents an analysis of teachers’ ratings on distance learning undergraduate study programs: 7,156 students enrolled in traditional and 528 students enrolled in distance learning studies took part in the evaluation questionnaire, assessing 71 teachers. The data were collected from the Moodle platform and from the Singidunum University information system, and then analysed with SPSS statistical software. The parameters considered as potentially affecting teacher ratings are: number of teachers engaged in a particular course, total number of courses in which the teacher is engaged, teacher’s gender and age, total number of the available resources, and so forth. The results imply that scores assigned to individual teachers are consistent in both traditional and distance learning programs. The average rate was perceived to be lower when there were several teachers in a single course; such an effect was enhanced in cases where there was a significant age discrepancy among them. The other factors considered did not show a significant association with teacher ratings. Students’ main remarks about the work of the teachers have been summarised at the end of this paper. Possible explanations and implications of the results are discussed and recommendations are given.

  17. Heart rate response to post-learning stress predicts memory consolidation.

    Science.gov (United States)

    Larra, Mauro F; Schulz, André; Schilling, Thomas M; Ferreira de Sá, Diana S; Best, Daniel; Kozik, Bartlomiej; Schächinger, Hartmut

    2014-03-01

    Stressful experiences are often well remembered, an effect that has been explained by beta-adrenergic influences on memory consolidation. Here, we studied the impact of stress induced heart rate (HR) responses on memory consolidation in a post-learning stress paradigm. 206 male and female participants saw 52 happy and angry faces immediately before being exposed to the Cold Pressor Test or a non-stressful control procedure. Memory for the faces and their respective expression was tested twice, after 30 min and on the next day. High HR responders (in comparison to low HR responders as well as to the non-stressful control group) showed enhanced recognition memory one day after learning. Our results show that beta-adrenergic activation elicited shortly after learning enhances memory consolidation and that the stress induced HR response is a predictor for this effect. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Rapid word-learning in normal-hearing and hearing-impaired children: effects of age, receptive vocabulary, and high-frequency amplification.

    Science.gov (United States)

    Pittman, A L; Lewis, D E; Hoover, B M; Stelmachowicz, P G

    2005-12-01

    This study examined rapid word-learning in 5- to 14-year-old children with normal and impaired hearing. The effects of age and receptive vocabulary were examined as well as those of high-frequency amplification. Novel words were low-pass filtered at 4 kHz (typical of current amplification devices) and at 9 kHz. It was hypothesized that (1) the children with normal hearing would learn more words than the children with hearing loss, (2) word-learning would increase with age and receptive vocabulary for both groups, and (3) both groups would benefit from a broader frequency bandwidth. Sixty children with normal hearing and 37 children with moderate sensorineural hearing losses participated in this study. Each child viewed a 4-minute animated slideshow containing 8 nonsense words created using the 24 English consonant phonemes (3 consonants per word). Each word was repeated 3 times. Half of the 8 words were low-pass filtered at 4 kHz and half were filtered at 9 kHz. After viewing the story twice, each child was asked to identify the words from among pictures in the slide show. Before testing, a measure of current receptive vocabulary was obtained using the Peabody Picture Vocabulary Test (PPVT-III). The PPVT-III scores of the hearing-impaired children were consistently poorer than those of the normal-hearing children across the age range tested. A similar pattern of results was observed for word-learning in that the performance of the hearing-impaired children was significantly poorer than that of the normal-hearing children. Further analysis of the PPVT and word-learning scores suggested that although word-learning was reduced in the hearing-impaired children, their performance was consistent with their receptive vocabularies. Additionally, no correlation was found between overall performance and the age of identification, age of amplification, or years of amplification in the children with hearing loss. Results also revealed a small increase in performance for both

  19. Pretraining Cortical Thickness Predicts Subsequent Perceptual Learning Rate in a Visual Search Task.

    Science.gov (United States)

    Frank, Sebastian M; Reavis, Eric A; Greenlee, Mark W; Tse, Peter U

    2016-03-01

    We report that preexisting individual differences in the cortical thickness of brain areas involved in a perceptual learning task predict the subsequent perceptual learning rate. Participants trained in a motion-discrimination task involving visual search for a "V"-shaped target motion trajectory among inverted "V"-shaped distractor trajectories. Motion-sensitive area MT+ (V5) was functionally identified as critical to the task: after 3 weeks of training, activity increased in MT+ during task performance, as measured by functional magnetic resonance imaging. We computed the cortical thickness of MT+ from anatomical magnetic resonance imaging volumes collected before training started, and found that it significantly predicted subsequent perceptual learning rates in the visual search task. Participants with thicker neocortex in MT+ before training learned faster than those with thinner neocortex in that area. A similar association between cortical thickness and training success was also found in posterior parietal cortex (PPC). © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. The Study of the Application Rate of Effective Learning Technologies in Self-Regulation of KFU and VIIU Students

    Science.gov (United States)

    Khuziakhmetov, Anvar N.; Amin, Azimi Sayed

    2015-01-01

    The aim of the present research is the study of the application rate of learning technologies in KFU and VIIU electronic courses to improve students' self-regulation. For this aim, this research was based on Kitsantas research, the rate of the use of effective learning technologies in students' self-regulation in electronic courses in these two…

  1. Training of tonal similarity ratings in non-musicians: a "rapid learning" approach.

    Science.gov (United States)

    Oechslin, Mathias S; Läge, Damian; Vitouch, Oliver

    2012-01-01

    Although cognitive music psychology has a long tradition of expert-novice comparisons, experimental training studies are rare. Studies on the learning progress of trained novices in hearing harmonic relationships are still largely lacking. This paper presents a simple training concept using the example of tone/triad similarity ratings, demonstrating the gradual progress of non-musicians compared to musical experts: In a feedback-based "rapid learning" paradigm, participants had to decide for single tones and chords whether paired sounds matched each other well. Before and after the training sessions, they provided similarity judgments for a complete set of sound pairs. From these similarity matrices, individual relational sound maps, intended to display mental representations, were calculated by means of non-metric multidimensional scaling (NMDS), and were compared to an expert model through procrustean transformation. Approximately half of the novices showed substantial learning success, with some participants even reaching the level of professional musicians. Results speak for a fundamental ability to quickly train an understanding of harmony, show inter-individual differences in learning success, and demonstrate the suitability of the scaling method used for learning research in music and other domains. Results are discussed in the context of the "giftedness" debate.

  2. Blood disappearance rate of /sup 198/Au-colloid and changes of hepatic blood flow during position change in normal persons and in patients with various hepatic diseases

    Energy Technology Data Exchange (ETDEWEB)

    Cho, B Y [Capital Armed Forces General Hospital, Seoul (Republic of Korea); Hong, K S; Koh, C S; Lee, M [Seoul National Univ., Seoul (Republic of Korea). Coll. of Medicine

    1977-01-01

    To evaluate the diagnostic significance of the blood disappearance rate of /sup 198/Au-colloid and to evaluate the change of hepatic blood flow during position change from supine to erect, we measured the half time of blood disappearance rate of 7,1/sup 98/Au-colloid using external counting method in 94 normal persons and in 77 patients with various hepatic diseases. The results obtained were as follows: 1. In normal control, the mean blood disappearance half time of /sup 198/Au-colloid in supine position was 2.7+-0.4 minutes. There was no significant difference of hepatic blood flow in age and sex. 2. In acute hepatitits, chronic hepatitis and hepatic cirrhosis, the mean blood disappearance half times in supine position were 3.0+-0.45, 3.5+-0.74, 7.2+-3.6 minutes respectively. The hepatic blood flow of the patients with chronic hepatitis and hepatic cirrhosis were significantly decreased than that of normal control. 3. In the normal control and acute hepatitis, the decreaces of the hepatic blood flow during the position change from supine to erect were 27.7% and 22.6% respectively.

  3. The blood disappearance rate of 198Au-colloid and changes of hepatic blood flow during position change in normal persons and in patients with various hepatic diseases

    International Nuclear Information System (INIS)

    Cho, B.Y.; Hong, K.S.; Koh, C.S.; Lee, M.

    1977-01-01

    To evaluate the diagnostic significance of the blood disappearance rate of 198 Au-colloid and to evaluate the change of hepatic blood flow during position change from supine to erect, we measured the half time of blood disappearance rate of 7,1 98 Au-colloid using external counting method in 94 normal persons and in 77 patients with various hepatic diseases. The results obtained were as follows: 1. In normal control, the mean blood disappearance half time of 198 Au-colloid in supine position was 2.7+-0.4 minutes. There was no significant difference of hepatic blood flow in age and sex. 2. In acute hepatitits, chronic hepatitis and hepatic cirrhosis, the mean blood disappearance half times in supine position were 3.0+-0.45, 3.5+-0.74, 7.2+-3.6 minutes respectively. The hepatic blood flow of the patients with chronic hepatitis and hepatic cirrhosis were significantly decreased than that of normal control. 3. In the normal control and acute hepatitis, the decreaces of the hepatic blood flow during the position change from supine to erect were 27.7% and 22.6% respectively. (author)

  4. The Blood Disappearance Rate of 198Au-Colloid and Changes of Hepatic Blood Flow During Position Change in Normal Persons and in Patients with Various Hepatic Diseases

    International Nuclear Information System (INIS)

    Cho, Bo Yeon; Hong, Kee Suk; Koh, Chang Soon; Lee, Mun Ho

    1977-01-01

    To evaluate the diagnostic significance of the blood disappearance rate of 198 Au-colloid and to evaluate the change of hepatic blood flow during position change from supine to erect, we measured the half time of blood disappearance rate of 198 Au-colloid using external counting method in 94 normal persons and in 77 patients with various hepatic diseases. The results obtained were as follows: 1) In normal control, the mean blood disappearance half time of 198 Au-colloid in supine position was 2.7±0.4 minutes. There was no significant difference of hepatic blood flow in age and sex. 2) In acute hepatitis, chronic hepatitis and hepatic cirrhosis, the mean blood disappearance half times in supine position were 3.0±0.45, 3.5±0.74, 7.2±3.6 minutes respectively. The hepatic blood flow of the patients with chronic hepatitis and hepatic cirrhosis were significantly decreased than that of normal control. 3) In the normal control and acute hepatitis, the decreases of the hepatic blood flow during the position change from supine to erect were 27.7% and 22.6% respectively.

  5. Design and Selection of Machine Learning Methods Using Radiomics and Dosiomics for Normal Tissue Complication Probability Modeling of Xerostomia.

    Science.gov (United States)

    Gabryś, Hubert S; Buettner, Florian; Sterzing, Florian; Hauswald, Henrik; Bangert, Mark

    2018-01-01

    The purpose of this study is to investigate whether machine learning with dosiomic, radiomic, and demographic features allows for xerostomia risk assessment more precise than normal tissue complication probability (NTCP) models based on the mean radiation dose to parotid glands. A cohort of 153 head-and-neck cancer patients was used to model xerostomia at 0-6 months (early), 6-15 months (late), 15-24 months (long-term), and at any time (a longitudinal model) after radiotherapy. Predictive power of the features was evaluated by the area under the receiver operating characteristic curve (AUC) of univariate logistic regression models. The multivariate NTCP models were tuned and tested with single and nested cross-validation, respectively. We compared predictive performance of seven classification algorithms, six feature selection methods, and ten data cleaning/class balancing techniques using the Friedman test and the Nemenyi post hoc analysis. NTCP models based on the parotid mean dose failed to predict xerostomia (AUCs  0.85), dose gradients in the right-left (AUCs > 0.78), and the anterior-posterior (AUCs > 0.72) direction. Multivariate models of long-term xerostomia were typically based on the parotid volume, the parotid eccentricity, and the dose-volume histogram (DVH) spread with the generalization AUCs ranging from 0.74 to 0.88. On average, support vector machines and extra-trees were the top performing classifiers, whereas the algorithms based on logistic regression were the best choice for feature selection. We found no advantage in using data cleaning or class balancing methods. We demonstrated that incorporation of organ- and dose-shape descriptors is beneficial for xerostomia prediction in highly conformal radiotherapy treatments. Due to strong reliance on patient-specific, dose-independent factors, our results underscore the need for development of personalized data-driven risk profiles for NTCP models of xerostomia. The facilitated

  6. Design and Selection of Machine Learning Methods Using Radiomics and Dosiomics for Normal Tissue Complication Probability Modeling of Xerostomia

    Directory of Open Access Journals (Sweden)

    Hubert S. Gabryś

    2018-03-01

    Full Text Available PurposeThe purpose of this study is to investigate whether machine learning with dosiomic, radiomic, and demographic features allows for xerostomia risk assessment more precise than normal tissue complication probability (NTCP models based on the mean radiation dose to parotid glands.Material and methodsA cohort of 153 head-and-neck cancer patients was used to model xerostomia at 0–6 months (early, 6–15 months (late, 15–24 months (long-term, and at any time (a longitudinal model after radiotherapy. Predictive power of the features was evaluated by the area under the receiver operating characteristic curve (AUC of univariate logistic regression models. The multivariate NTCP models were tuned and tested with single and nested cross-validation, respectively. We compared predictive performance of seven classification algorithms, six feature selection methods, and ten data cleaning/class balancing techniques using the Friedman test and the Nemenyi post hoc analysis.ResultsNTCP models based on the parotid mean dose failed to predict xerostomia (AUCs < 0.60. The most informative predictors were found for late and long-term xerostomia. Late xerostomia correlated with the contralateral dose gradient in the anterior–posterior (AUC = 0.72 and the right–left (AUC = 0.68 direction, whereas long-term xerostomia was associated with parotid volumes (AUCs > 0.85, dose gradients in the right–left (AUCs > 0.78, and the anterior–posterior (AUCs > 0.72 direction. Multivariate models of long-term xerostomia were typically based on the parotid volume, the parotid eccentricity, and the dose–volume histogram (DVH spread with the generalization AUCs ranging from 0.74 to 0.88. On average, support vector machines and extra-trees were the top performing classifiers, whereas the algorithms based on logistic regression were the best choice for feature selection. We found no advantage in using data cleaning or class balancing

  7. Morphological evolution of dissolving feldspar particles with anisotropic surface kinetics and implications for dissolution rate normalization and grain size dependence: A kinetic modeling study

    Science.gov (United States)

    Zhang, Li; Lüttge, Andreas

    2009-11-01

    With previous two-dimensional (2D) simulations based on surface-specific feldspar dissolution succeeding in relating the macroscopic feldspar kinetics to the molecular-scale surface reactions of Si and Al atoms ( Zhang and Lüttge, 2008, 2009), we extended our modeling effort to three-dimensional (3D) feldspar particle dissolution simulations. Bearing on the same theoretical basis, the 3D feldspar particle dissolution simulations have verified the anisotropic surface kinetics observed in the 2D surface-specific simulations. The combined effect of saturation state, pH, and temperature on the surface kinetics anisotropy has been subsequently evaluated, found offering diverse options for morphological evolution of dissolving feldspar nanoparticles with varying grain sizes and starting shapes. Among the three primary faces on the simulated feldspar surface, the (1 0 0) face has the biggest dissolution rate across an extensively wide saturation state range and thus acquires a higher percentage of the surface area upon dissolution. The slowest dissolution occurs to either (0 0 1) or (0 1 0) faces depending on the bond energies of Si-(O)-Si ( ΦSi-O-Si/ kT) and Al-(O)-Si ( ΦAl-O-Si/ kT). When the ratio of ΦSi-O-Si/ kT to ΦAl-O-Si/ kT changes from 6:3 to 7:5, the dissolution rates of three primary faces change from the trend of (1 0 0) > (0 1 0) > (0 0 1) to the trend of (1 0 0) > (0 0 1) > (0 1 0). The rate difference between faces becomes more distinct and accordingly edge rounding becomes more significant. Feldspar nanoparticles also experience an increasing degree of edge rounding from far-from-equilibrium to close-to-equilibrium. Furthermore, we assessed the connection between the continuous morphological modification and the variation in the bulk dissolution rate during the dissolution of a single feldspar particle. Different normalization treatments equivalent to the commonly used mass, cube assumption, sphere assumption, geometric surface area, and reactive

  8. Motor proficiency in normal children and with learning difficulty: a comparative and correlational study based on the motor proficiency test of Bruininks-Oseretsky

    Directory of Open Access Journals (Sweden)

    Nilson Roberto Moreira

    2008-06-01

    Full Text Available The aim of this investigation is to verify the difference between children with learning disabilities and children without learning disabilities through motor proficiency test of Bruininks and Ozeretsky (1978. The sample was constituted by 30 children, with 8-year average age, 15 males and 15 females, subdivided into two groups of 15 children from both sexes: children without learning disabilities attending 3rd grade and children with learning disabilities attending 2nd grade having failed a term once. All of them came from a middle class background, according to Grafar scale (adapted by Fonseca, 1991. All children presenting any other disabilities were excluded from the sample. Intelligence factor “G” was controlled by using a percentile, higher or equal to 50 (middle and high level, measured by Raven’s (1974 progressive combinations test. In motor proficiency, children with learning disabilities showed significant differences when compared with normal children of the same age, in all components of global, composed and fine motricity. The tests administered showed a strong correlation between the variables of the motor proficiency components. The results lead to the conclusion that there were significant differences in motor proficiency between normal children and children with learning disabilities, who showed specific motor difficulties evincing a more vulnerable motor profile and not the presence of neurological dysfunction signs.

  9. Effect of mental challenge induced by movie clips on action potential duration in normal human subjects independent of heart rate.

    Science.gov (United States)

    Child, Nicholas; Hanson, Ben; Bishop, Martin; Rinaldi, Christopher A; Bostock, Julian; Western, David; Cooklin, Michael; O'Neil, Mark; Wright, Matthew; Razavi, Reza; Gill, Jaswinder; Taggart, Peter

    2014-06-01

    Mental stress and emotion have long been associated with ventricular arrhythmias and sudden death in animal models and humans. The effect of mental challenge on ventricular action potential duration (APD) in conscious healthy humans has not been reported. Activation recovery intervals measured from unipolar electrograms as a surrogate for APD (n=19) were recorded from right and left ventricular endocardium during steady-state pacing, whilst subjects watched an emotionally charged film clip. To assess the possible modulating role of altered respiration on APD, the subjects then repeated the same breathing pattern they had during the stress, but without the movie clip. Hemodynamic parameters (mean, systolic, and diastolic blood pressure, and rate of pressure increase) and respiration rate increased during the stressful part of the film clip (P=0.001). APD decreased during the stressful parts of the film clip, for example, for global right ventricular activation recovery interval at end of film clip 193.8 ms (SD, 14) versus 198.0 ms (SD, 13) during the matched breathing control (end film left ventricle 199.8 ms [SD, 16] versus control 201.6 ms [SD, 15]; P=0.004). Respiration rate increased during the stressful part of the film clip (by 2 breaths per minute) and was well matched in the respective control period without any hemodynamic or activation recovery interval changes. Our results document for the first time direct recordings of the effect of a mental challenge protocol on ventricular APD in conscious humans. The effect of mental challenge on APD was not secondary to emotionally induced altered respiration or heart rate. © 2014 American Heart Association, Inc.

  10. Combining Unsupervised and Supervised Statistical Learning Methods for Currency Exchange Rate Forecasting

    OpenAIRE

    Vasiljeva, Polina

    2016-01-01

    In this thesis we revisit the challenging problem of forecasting currency exchange rate. We combine machine learning methods such as agglomerative hierarchical clustering and random forest to construct a two-step approach for predicting movements in currency exchange prices of the Swedish krona and the US dollar. We use a data set with over 200 predictors comprised of different financial and macro-economic time series and their transformations. We perform forecasting for one week ahead with d...

  11. Assessment of cardiac performance with quantitative radionuclide angiocardiography: sequential left ventricular ejection fraction, normalized left ventricular ejection rate, and regional wall motion

    International Nuclear Information System (INIS)

    Marshall, R.C.; Berger, H.J.; Costin, J.C.; Freedman, G.S.; Wolberg, J.; Cohen, L.S.; Gotischalk, A.; Zaret, B.L.

    1977-01-01

    Sequential quantitative first pass radionuclide angiocardiograms (RA) were used to measure left ventricular ejection fraction (LVEF) and left ventricular ejection rate (LVER), and to assess regional wall motion (RWM) in the anterior (ANT) and left anterior oblique (LAO) positions. Studies were obtained with a computerized multicrystal scintillation camera suitable for acquiring high count-rate data. Background was determined in a new fashion by selecting frames temporally from the left ventricular region of interest time-activity curve. A ''representative'' cardiac cycle was formed by summing together counts over three to six cardiac cycles. From this background corrected, high count-rate ''representative''cardiac cycle, LVEF, LVER, and RWM were determined. In 22 patients with normal sinus rhythm in the absence of significant valvular regurgitation, RA LVEF correlated well with that measured by contrast angiography (r = 0.95). LVER correlated well with LVEF measured at contrast angiography (r = 0.90) and allowed complete separation of those with normal (LVER = 3.4 +- 0.17 sec -1 ) and abnormal (LVER = 1.22 +- 0.11 sec -1 ) (P < 0.001) left ventricular performance. This separation was independent of background. Isoproterenol infusion in five normal subjects caused LVER to increase by 81 +- 17% while LVEF increased by 10 +- 2.0%. RWM was correctly defined in 21/22 patients and 89% of left ventricular segments with abnormal wall motion

  12. Radiobiological equivalent of low/high dose rate brachytherapy and evaluation of tumor and normal responses to the dose.

    Science.gov (United States)

    Manimaran, S

    2007-06-01

    The aim of this study was to compare the biological equivalent of low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy in terms of the more recent linear quadratic (LQ) model, which leads to theoretical estimation of biological equivalence. One of the key features of the LQ model is that it allows a more systematic radiobiological comparison between different types of treatment because the main parameters alpha/beta and micro are tissue-specific. Such comparisons also allow assessment of the likely change in the therapeutic ratio when switching between LDR and HDR treatments. The main application of LQ methodology, which focuses on by increasing the availability of remote afterloading units, has been to design fractionated HDR treatments that can replace existing LDR techniques. In this study, with LDR treatments (39 Gy in 48 h) equivalent to 11 fractions of HDR irradiation at the experimental level, there are increasing reports of reproducible animal models that may be used to investigate the biological basis of brachytherapy and to help confirm theoretical predictions. This is a timely development owing to the nonavailability of sufficient retrospective patient data analysis. It appears that HDR brachytherapy is likely to be a viable alternative to LDR only if it is delivered without a prohibitively large number of fractions (e.g., fewer than 11). With increased scientific understanding and technological capability, the prospect of a dose equivalent to HDR brachytherapy will allow greater utilization of the concepts discussed in this article.

  13. Inhibitory interneuron progenitor transplantation restores normal learning and memory in ApoE4 knock-in mice without or with Aβ accumulation.

    Science.gov (United States)

    Tong, Leslie M; Djukic, Biljana; Arnold, Christine; Gillespie, Anna K; Yoon, Seo Yeon; Wang, Max M; Zhang, Olivia; Knoferle, Johanna; Rubenstein, John L R; Alvarez-Buylla, Arturo; Huang, Yadong

    2014-07-16

    Excitatory and inhibitory balance of neuronal network activity is essential for normal brain function and may be of particular importance to memory. Apolipoprotein (apo) E4 and amyloid-β (Aβ) peptides, two major players in Alzheimer's disease (AD), cause inhibitory interneuron impairments and aberrant neuronal activity in the hippocampal dentate gyrus in AD-related mouse models and humans, leading to learning and memory deficits. To determine whether replacing the lost or impaired interneurons rescues neuronal signaling and behavioral deficits, we transplanted embryonic interneuron progenitors into the hippocampal hilus of aged apoE4 knock-in mice without or with Aβ accumulation. In both conditions, the transplanted cells developed into mature interneurons, functionally integrated into the hippocampal circuitry, and restored normal learning and memory. Thus, restricted hilar transplantation of inhibitory interneurons restores normal cognitive function in two widely used AD-related mouse models, highlighting the importance of interneuron impairments in AD pathogenesis and the potential of cell replacement therapy for AD. More broadly, it demonstrates that excitatory and inhibitory balance are crucial for learning and memory, and suggests an avenue for investigating the processes of learning and memory and their alterations in healthy aging and diseases. Copyright © 2014 the authors 0270-6474/14/349506-10$15.00/0.

  14. Enhancement of relaxation rates in the normal state of superconductor PuRhGa5:NQR relaxation study

    International Nuclear Information System (INIS)

    Sakai, H.; Kambe, S.; Tokunaga, Y.; Fujimoto, T.; Walstedt, R.E.; Yasuoka, H.; Aoki, D.; Homma, Y.; Yamamoto, E.; Nakamura, A.; Shiokawa, Y.; Nakajima, K.; Arai, Y.; Matsuda, T.D.; Haga, Y.; Onuki, Y.

    2007-01-01

    The spin-lattice relaxation rates (1/T 1 ) have been measured under zero field using nuclear quadrupole resonance (NQR) lines in superconductor PuRhGa 5 and Pauli-paramagnet LuCoGa 5 . In the reference LuCoGa 5 with fully-occupied 4f shell, the 1/T 1 shows the constant behavior of (T 1 T) -1 =0.495+/-0.002(sK) -1 . On the other hand, in PuRhGa 5 , 1/T 1 is much larger than in LuCoGa 5 and the 1/T 1 ∝T behavior below ∼30K is seen, where its (T 1 T) -1 value is 3.27+/-0.005(sK) -1 . These results suggest a development of coherent Fermi liquid state incorporated with 5f electrons below ∼30K in PuRhGa 5

  15. Could Intermittent Energy Restriction and Intermittent Fasting Reduce Rates of Cancer in Obese, Overweight, and Normal-Weight Subjects? A Summary of Evidence.

    Science.gov (United States)

    Harvie, Michelle N; Howell, Tony

    2016-07-01

    Animal studies and human observational data link energy restriction (ER) to reduced rates of carcinogenesis. Most of these studies have involved continuous energy restriction (CER), but there is increasing public and scientific interest in the potential health and anticancer effects of intermittent energy restriction (IER) or intermittent fasting (IF), which comprise periods of marked ER or total fasting interspersed with periods of normal eating. This review summarizes animal studies that assessed tumor rates with IER and IF compared with CER or ad libitum feed consumption. The relevance of these animal data to human cancer is also considered by summarizing available human studies of the effects of IER or IF compared with CER on cancer biomarkers in obese, overweight, and normal-weight subjects. IER regimens that include periods of ER alternating with ad libitum feed consumption for 1, 2, or 3 wk have been reported to be superior to CER in reducing tumor rates in most spontaneous mice tumor models. Limited human data from short-term studies (≤6 mo) in overweight and obese subjects have shown that IER can lead to greater improvements in insulin sensitivity (homeostasis model assessment) than can CER, with comparable reductions in adipokines and inflammatory markers and minor changes in the insulin-like growth factor axis. There are currently no data comparing IER or IF with CER in normal-weight subjects. The benefits of IER in these short-term trials are of interest, but not sufficient evidence to recommend the use of IER above CER. Longer-term human studies of adherence to and efficacy and safety of IER are required in obese and overweight subjects, as well as normal-weight subjects. © 2016 American Society for Nutrition.

  16. [{sup 123}]FP-CIT SPECT scans initially rated as normal became abnormal over time in patients with probable dementia with Lewy bodies

    Energy Technology Data Exchange (ETDEWEB)

    Zande, J.J. van der; Scheltens, P.; Lemstra, A.W. [VU Medical Center Alzheimer Center, Amsterdam (Netherlands); Booij, J. [Academic Medical Center, Department of Nuclear Medicine, Amsterdam (Netherlands); Raijmakers, P.G.H.M. [VU Medical Center, Department of Nuclear Medicine, Amsterdam (Netherlands)

    2016-06-15

    Decreased striatal dopamine transporter (DAT) binding on SPECT imaging is a strong biomarker for the diagnosis of dementia with Lewy bodies (DLB). There is still a lot of uncertainty about patients meeting the clinical criteria for probable DLB who have a normal DAT SPECT scan (DLB/S-). The aim of this study was to describe the clinical and imaging follow-up in these patients, and compare them to DLB patients with abnormal baseline scans (DLB/S+). DLB patients who underwent DAT imaging ([{sup 123}I]FP-CIT SPECT) were selected from the Amsterdam Dementia Cohort. All [{sup 123}I]FP-CIT SPECT scans were evaluated independently by two nuclear medicine physicians and in patients with normal scans follow-up imaging was obtained. We matched DLB/S- patients for age and disease duration to DLB/S+ patients and compared their clinical characteristics. Of 67 [{sup 123}I]FP-CIT SPECT scans, 7 (10.4 %) were rated as normal. In five DLB/S- patients, a second [{sup 123}I]FP-CIT SPECT was performed (after on average 1.5 years) and these scans were all abnormal. No significant differences in clinical characteristics were found at baseline. DLB/S- patients could be expected to have a better MMSE score after 1 year. This study was the first to investigate DLB patients with the initial [{sup 123}I]FP-CIT SPECT scan rated as normal and subsequent scans during disease progression rated as abnormal. We hypothesize that DLB/S- scans could represent a relatively rare DLB subtype with possibly a different severity or spread of alpha-synuclein pathology (''neocortical predominant subtype''). In clinical practice, if an alternative diagnosis is not imminent in a DLB/S- patient, repeating [{sup 123}I]FP-CIT SPECT should be considered. (orig.)

  17. Could Intermittent Energy Restriction and Intermittent Fasting Reduce Rates of Cancer in Obese, Overweight, and Normal-Weight Subjects? A Summary of Evidence12

    Science.gov (United States)

    2016-01-01

    Animal studies and human observational data link energy restriction (ER) to reduced rates of carcinogenesis. Most of these studies have involved continuous energy restriction (CER), but there is increasing public and scientific interest in the potential health and anticancer effects of intermittent energy restriction (IER) or intermittent fasting (IF), which comprise periods of marked ER or total fasting interspersed with periods of normal eating. This review summarizes animal studies that assessed tumor rates with IER and IF compared with CER or ad libitum feed consumption. The relevance of these animal data to human cancer is also considered by summarizing available human studies of the effects of IER or IF compared with CER on cancer biomarkers in obese, overweight, and normal-weight subjects. IER regimens that include periods of ER alternating with ad libitum feed consumption for 1, 2, or 3 wk have been reported to be superior to CER in reducing tumor rates in most spontaneous mice tumor models. Limited human data from short-term studies (≤6 mo) in overweight and obese subjects have shown that IER can lead to greater improvements in insulin sensitivity (homeostasis model assessment) than can CER, with comparable reductions in adipokines and inflammatory markers and minor changes in the insulin-like growth factor axis. There are currently no data comparing IER or IF with CER in normal-weight subjects. The benefits of IER in these short-term trials are of interest, but not sufficient evidence to recommend the use of IER above CER. Longer-term human studies of adherence to and efficacy and safety of IER are required in obese and overweight subjects, as well as normal-weight subjects. PMID:27422504

  18. Training of tonal similarity ratings in non-musicians: a rapid learning approach

    Directory of Open Access Journals (Sweden)

    Mathias S Oechslin

    2012-05-01

    Full Text Available Although music psychology has a long tradition of expert-novice comparisons, experimental training studies are rare. Studies on the learning progress of trained novices in hearing harmonic relationships are still largely lacking. This paper presents a simple training concept using the example of tone/triad similarity ratings, demonstrating the gradual progress of non-musicians compared to musical experts: In a feedback-based rapid learning paradigm, participants had to decide for single tones and chords whether paired sounds matched each other well. Before and after the training sessions, they provided similarity judgments for a complete set of sound pairs. From these similarity matrices, individual relational sound maps, aiming to map the mental representations, were calculated by means of non-metric multidimensional scaling (NMDS, which were compared to an expert model through procrustean transformation. Approximately half of the novices showed substantial learning success, with some participants even reaching the level of professional musicians. Results speak for a fundamental ability to quickly train an understanding of harmony, show inter-individual differences in learning success, and demonstrate the suitability of the scaling method used for music psychological research. Results are discussed in the context of the giftedness debate.

  19. Normalization of water flow rate for external fire fighting of the buildings in settlements with zone water supply

    Directory of Open Access Journals (Sweden)

    Deryushev Leonid Georgievich

    2014-12-01

    Full Text Available In the article the requirements for fire safety assurance are justified for the objects, in which water is supplied with account for serial and parallel area zoning. In the process of zoning the district is segregated into such parts, for which head rate in any point of selection of water from network will not exceed 6 bar. In the current regulatory rules the requirements for the calculation of the costs of water points are stated, as well as in case of extinguishing fires at the sites with water-supply systems zones. It is recommended to analyze each zone of the system of water-supply separately, without interrelation with the common water feeders, water consumers and services of fire extinguishing. Such an approach to assign water discharge for fire extinguishing results in the decrease of fire safety of an object, deforms calculation technique of outside systems of water-supply of the similar-type objects located in different parts of the terrain. Taking the number of fires and water consumption for fire suppression by the number of residents in each zone, we thus underestimate the capacity of the pipeline system. It is offered to make changes in Norms and Standards in force on fire safety of settlements. The recommendations on regulation of the number of fires and water flow for fire fighting in residential objects with zoned systems of water-supply are formulated.

  20. Self-rated driving habits among older adults with clinically-defined mild cognitive impairment, clinically-defined dementia, and normal cognition.

    Science.gov (United States)

    O'Connor, Melissa L; Edwards, Jerri D; Bannon, Yvonne

    2013-12-01

    Older adults with clinically-defined dementia may report reducing their driving more than cognitively normal controls. However, it is unclear how these groups compare to individuals with clinically-defined mild cognitive impairment (MCI) in terms of driving behaviors. The current study investigated self-reported driving habits among adults age 60 and older with clinical MCI (n=41), clinical mild dementia (n=40), and normal cognition (n=43). Participants reported their driving status, driving frequency (days per week), and how often they avoided accessing the community, making left turns, driving at night, driving in unfamiliar areas, driving on high-traffic roads, and driving in bad weather. After adjusting for education, a MANCOVA revealed that participants with MCI and dementia avoided unfamiliar areas and high-traffic roads significantly more than normal participants. Participants with dementia also avoided left turns and accessing the community more than those with normal cognition and MCI (pdriving variables did not significantly differ between groups. Thus, older adults with clinically-defined MCI, as well as those with dementia, avoided some complex driving situations more than cognitively intact adults. However, all diagnostic groups had similar rates of driving cessation and frequency. Future research should examine the safety implications of such findings. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. A self-directed learning intervention for radiographers rating mammographic breast density

    International Nuclear Information System (INIS)

    Ekpo, E.U.; Hogg, P.; Wasike, E.; McEntee, M.F.

    2017-01-01

    Purpose: Subjective methods of mammographic breast density (MBD) assessment are prone to inter-reader variability. This work aims to assess the impact of a short self-directed, experiential learning intervention on radiographers' reproducibility of MBD assessment. Method: The study used two sets of images (test and learning intervention) containing left craniocaudal and left mediolateral oblique views. The test set had MBD ratings from Volpara™ and radiologists using the fourth edition Breast Imaging and Data Systems (BI-RADS ® ). Seven radiographers rated the MBD of the test set before and after a self-directed learning intervention using the percentage descriptors in the fourth edition BI-RADS ® Atlas. The inter-reader agreement, the agreement between radiographers and Volpara™ as well as radiologists, was assessed using a Weighted Kappa (κ w ). Results: Overall, radiographers' inter-reader agreement (κ w ) was substantial (0.79; 95% CI: 0.70–0.87) before the intervention and almost perfect (0.84; 95% CI: 0.77–0.90) after the intervention. Before the intervention, radiographers demonstrated fair agreement with radiologists (0.24; 95% CI: −0.46–0.61) and Volpara™ (0.24; 95% CI: −0.41–0.59). A fair but slightly improved agreement was also observed between radiographers and radiologists (0.31; 95% CI: −0.33–0.64) as well as Volpara™ (0.28; 95% CI: −0.34–0.61) after the intervention. Conclusion: Findings demonstrate that a short duration self-directed, experiential learning intervention reduces inter-reader differences in MBD classification, but has a negligible impact on improving the agreement between inexperienced and expert readers. - Highlights: • Radiographers' MBD rating show fair agreement with radiologists and Volpara™. • Experiential learning intervention improved reproducibility of MBD classification. • Enhanced MBD rating training may be required to develop a standard fit for practice.

  2. Baseline performance and learning rate of conceptual and perceptual skill-learning tasks: the effect of moderate to severe traumatic brain injury.

    Science.gov (United States)

    Vakil, Eli; Lev-Ran Galon, Carmit

    2014-01-01

    Existing literature presents a complex and inconsistent picture of the specific deficiencies involved in skill learning following traumatic brain injury (TBI). In an attempt to address this difficulty, individuals with moderate to severe TBI (n = 29) and a control group (n = 29) were tested with two different skill-learning tasks: conceptual (i.e., Tower of Hanoi Puzzle, TOHP) and perceptual (i.e., mirror reading, MR). Based on previous studies of the effect of divided attention on these tasks and findings regarding the effect of TBI on conceptual and perceptual priming tasks, it was predicted that the group with TBI would show impaired baseline performance compared to controls in the TOHP task though their learning rate would be maintained, while both baseline performance and learning rate on the MR task would be maintained. Consistent with our predictions, overall baseline performance of the group with TBI was impaired in the TOHP test, while the learning rate was not. The learning rate on the MR task was preserved but, contrary to our prediction, response time of the group with TBI was slower than that of controls. The pattern of results observed in the present study was interpreted to possibly reflect an impairment of both the frontal lobes as well as that of diffuse axonal injury, which is well documented as being affected by TBI. The former impairment affects baseline performance of the conceptual learning skill, while the latter affects the overall slower performance of the perceptual learning skill.

  3. Impact of problem-based, active learning on graduation rates for 10 generations of Dutch medical students.

    Science.gov (United States)

    Schmidt, Henk G; Cohen-Schotanus, Janke; Arends, Lidia R

    2009-03-01

    We aimed to study the effects of active-learning curricula on graduation rates of students and on the length of time needed to graduate. Graduation rates for 10 generations of students enrolling in the eight Dutch medical schools between 1989 and 1998 were analysed. In addition, time needed to graduate was recorded. Three of the eight schools had curricula emphasising active learning, small-group instruction and limited numbers of lectures; the other five had conventional curricula to varying degrees. Overall, the active-learning curricula graduated on average 8% more students per year, and these students graduated on average 5 months earlier than their colleagues from conventional curricula. Four hypotheses potentially explaining the effect of active learning on graduation rate and study duration were considered: (i) active-learning curricula promote the social and academic integration of students; (ii) active-learning curricula attract brighter students; (iii) active-learning curricula retain more poor students, and (iv) the active engagement of students with their study required by active-learning curricula induces better academic performance and, hence, lower dropout rates. The first three hypotheses had to be rejected. It was concluded that the better-learning hypothesis provides the most parsimonious account for the data.

  4. Ab initio calculation of transition state normal mode properties and rate constants for the H(T)+CH4(CD4) abstraction and exchange reactions

    International Nuclear Information System (INIS)

    Schatz, G.C.; Walch, S.P.; Wagner, A.F.

    1980-01-01

    We present ab initio (GVB--POL--CI) calculations for enough of the region about the abstraction and exchange saddle points for H(T)+CH 4 (CD 4 ) to perform a full normal mode analysis of the transition states. The resulting normal mode frequencies are compared to four other published surfaces: an ab initio UHF--SCF calculation by Carsky and Zahradnik, a semiempirical surface by Raff, and two semiempirical surfaces by Kurylo, Hollinden, and Timmons. Significant quantitative and qualitative differences exist between the POL--CI results and those of the other surfaces. Transition state theory rate constants and vibrationally adiabatic reaction threshold energies were computed for all surfaces and compared to available experimental values. For abstraction, the POL--CI rates are in good agreement with experimental rates and in better agreement than are the rates of any of the other surfaces. For exchange, uncertainties in the experimental values and in the importance of vibrationally nonadiabatic effects cloud the comparison of theory to experiment. Tentative conclusions are that the POL--CI barrier is too low by several kcal. Unless vibrationaly nonadiabatic effects are severe, the POL--CI surface is still in better agreement with experiment than are the other surfaces. The rates for a simple 3-atom transition state theory model (where CH 3 is treated as an atom) are compared to the rates for the full 6-atom model. The kinetic energy coupling of reaction coordinate modes to methyl group modes is identified as being of primary importance in determining the accuracy of the 3-atom model for this system. Substantial coupling in abstraction, but not exchange, causes the model to fail for abstraction but succeed for exchange

  5. Dose-rate effects between 0.3 and 30 Gy/h in a normal and a malignant human cell line

    International Nuclear Information System (INIS)

    Amdur, R.J.; Bedford, J.S.

    1994-01-01

    This study used continuous open-quotes intermediateclose quotes dose rate irradiation (0.3-30 Gy/h) to compare the capacity for and repair of sublethal radiation damage in different cell lines growing in tissue culture. Two human cell lines were studied; one was derived from normal human fibroblasts (AG1522) and the other from a squamous cell carcinoma of the uterine cervix (HTB-35). Dose-response curves for clonogenic survival were determined following irradiation of plateau-phase cultures at five different dose rates: 22.6, 6.12, 3.65, 1.04, and 0.38 Gy/h. Subculture following irradiation was delayed for 8-24 h to allow for the full repair of open-quotes potentially lethal damage.close quotes A significant dose-rate effect was seen in both cell lines. For irradiation at the highest dose rate, survival at 2 Gy (SF2) and the α/β ratio were similar for the two cell lines (approximately 0.7 and 8.0 Gy, respectively) but the half-time of repair of sublethal damage was estimated to be approximately five times longer in the normal human fibroblast line (154 min) than in the carcinoma (31 min) cell line. These results indicate that measuring the dose-rate effect between 0.3 and 30 Gy/h is a useful way to identify and quantify differences in sublethal damage repair between cell lines. To the extent that in vitro and in vivo repair parameters are similar, and that representative tumor biopsy specimens can be examined in this way, this approach may provide a prospective way of determining the dose rate (brachytherapy) or fractionation schedule that will optimize the therapeutic ratio. 32 refs., 1 fig

  6. Cumulative and current exposure to potentially nephrotoxic antiretrovirals and development of chronic kidney disease in HIV-positive individuals with a normal baseline estimated glomerular filtration rate

    DEFF Research Database (Denmark)

    Mocroft, Amanda; Lundgren, Jens D; Ross, Michael

    2016-01-01

    BACKGROUND: Whether or not the association between some antiretrovirals used in HIV infection and chronic kidney disease is cumulative is a controversial topic, especially in patients with initially normal renal function. In this study, we aimed to investigate the association between duration...... of exposure to antiretrovirals and the development of chronic kidney disease in people with initially normal renal function, as measured by estimated glomerular filtration rate (eGFR). METHODS: In this prospective international cohort study, HIV-positive adult participants (aged ≥16 years) from the D......:A:D study (based in Europe, the USA, and Australia) with first eGFR greater than 90 mL/min per 1·73 m(2) were followed from baseline (first eGFR measurement after Jan 1, 2004) until the occurrence of one of the following: chronic kidney disease; last eGFR measurement; Feb 1, 2014; or final visit plus 6...

  7. Learning to maximize reward rate: a model based on semi-Markov decision processes.

    Science.gov (United States)

    Khodadadi, Arash; Fakhari, Pegah; Busemeyer, Jerome R

    2014-01-01

    WHEN ANIMALS HAVE TO MAKE A NUMBER OF DECISIONS DURING A LIMITED TIME INTERVAL, THEY FACE A FUNDAMENTAL PROBLEM: how much time they should spend on each decision in order to achieve the maximum possible total outcome. Deliberating more on one decision usually leads to more outcome but less time will remain for other decisions. In the framework of sequential sampling models, the question is how animals learn to set their decision threshold such that the total expected outcome achieved during a limited time is maximized. The aim of this paper is to provide a theoretical framework for answering this question. To this end, we consider an experimental design in which each trial can come from one of the several possible "conditions." A condition specifies the difficulty of the trial, the reward, the penalty and so on. We show that to maximize the expected reward during a limited time, the subject should set a separate value of decision threshold for each condition. We propose a model of learning the optimal value of decision thresholds based on the theory of semi-Markov decision processes (SMDP). In our model, the experimental environment is modeled as an SMDP with each "condition" being a "state" and the value of decision thresholds being the "actions" taken in those states. The problem of finding the optimal decision thresholds then is cast as the stochastic optimal control problem of taking actions in each state in the corresponding SMDP such that the average reward rate is maximized. Our model utilizes a biologically plausible learning algorithm to solve this problem. The simulation results show that at the beginning of learning the model choses high values of decision threshold which lead to sub-optimal performance. With experience, however, the model learns to lower the value of decision thresholds till finally it finds the optimal values.

  8. The effect of speaking rate on serial-order sound-level errors in normal healthy controls and persons with aphasia.

    Science.gov (United States)

    Fossett, Tepanta R D; McNeil, Malcolm R; Pratt, Sheila R; Tompkins, Connie A; Shuster, Linda I

    Although many speech errors can be generated at either a linguistic or motoric level of production, phonetically well-formed sound-level serial-order errors are generally assumed to result from disruption of phonologic encoding (PE) processes. An influential model of PE (Dell, 1986; Dell, Burger & Svec, 1997) predicts that speaking rate should affect the relative proportion of these serial-order sound errors (anticipations, perseverations, exchanges). These predictions have been extended to, and have special relevance for persons with aphasia (PWA) because of the increased frequency with which speech errors occur and because their localization within the functional linguistic architecture may help in diagnosis and treatment. Supporting evidence regarding the effect of speaking rate on phonological encoding has been provided by studies using young normal language (NL) speakers and computer simulations. Limited data exist for older NL users and no group data exist for PWA. This study tested the phonologic encoding properties of Dell's model of speech production (Dell, 1986; Dell,et al., 1997), which predicts that increasing speaking rate affects the relative proportion of serial-order sound errors (i.e., anticipations, perseverations, and exchanges). The effects of speech rate on the error ratios of anticipation/exchange (AE), anticipation/perseveration (AP) and vocal reaction time (VRT) were examined in 16 normal healthy controls (NHC) and 16 PWA without concomitant motor speech disorders. The participants were recorded performing a phonologically challenging (tongue twister) speech production task at their typical and two faster speaking rates. A significant effect of increased rate was obtained for the AP but not the AE ratio. Significant effects of group and rate were obtained for VRT. Although the significant effect of rate for the AP ratio provided evidence that changes in speaking rate did affect PE, the results failed to support the model derived predictions

  9. Learning Materials Recommendation Using Good Learners' Ratings and Content-Based Filtering

    Science.gov (United States)

    Ghauth, Khairil Imran; Abdullah, Nor Aniza

    2010-01-01

    The enormity of the amount of learning materials in e-learning has led to the difficulty of locating suitable learning materials for a particular learning topic, creating the need for recommendation tools within a learning context. In this paper, we aim to address this need by proposing a novel e-learning recommender system framework that is based…

  10. Saliva composition in three selected groups with normal stimulated salivary flow rates, but yet major differences in caries experience and dental erosion.

    Science.gov (United States)

    Bardow, Allan; Lykkeaa, Joan; Qvist, Vibeke; Ekstrand, Kim; Twetman, Svante; Fiehn, Niels-Erik

    2014-08-01

    It was hypothesized that, by comparing matched subjects with major differences in these dental diseases, but yet normal saliva flow rates, it would be possible to obtain data on the effect of saliva composition on dental disease isolated from the effect of the flow rate. Thus, the aim of the study was to compare the major physicochemical characteristics of stimulated whole saliva in three groups of 85 subjects, each with normal saliva flow rates and at least 24 remaining teeth. A group with very little dental disease (healthy), a group with dental erosion (erosion) and a group with very high caries experience (caries) were chosen. Furthermore, the aim was to determine whether differences among groups could also be found on an individual level. Although it was not possible to retrieve three groups whose members were completely identical, the present study points in the direction that, on a group level, subjects with very little dental disease seemed to have a more favorable physicochemical saliva composition with respect to higher calcium, phosphate, bicarbonate, pH, degree of saturation with respect to hydroxyapatite and a lower critical pH (p dental erosion (p dental caries and erosion in single individuals.

  11. Joint Machine Learning and Game Theory for Rate Control in High Efficiency Video Coding.

    Science.gov (United States)

    Gao, Wei; Kwong, Sam; Jia, Yuheng

    2017-08-25

    In this paper, a joint machine learning and game theory modeling (MLGT) framework is proposed for inter frame coding tree unit (CTU) level bit allocation and rate control (RC) optimization in High Efficiency Video Coding (HEVC). First, a support vector machine (SVM) based multi-classification scheme is proposed to improve the prediction accuracy of CTU-level Rate-Distortion (R-D) model. The legacy "chicken-and-egg" dilemma in video coding is proposed to be overcome by the learning-based R-D model. Second, a mixed R-D model based cooperative bargaining game theory is proposed for bit allocation optimization, where the convexity of the mixed R-D model based utility function is proved, and Nash bargaining solution (NBS) is achieved by the proposed iterative solution search method. The minimum utility is adjusted by the reference coding distortion and frame-level Quantization parameter (QP) change. Lastly, intra frame QP and inter frame adaptive bit ratios are adjusted to make inter frames have more bit resources to maintain smooth quality and bit consumption in the bargaining game optimization. Experimental results demonstrate that the proposed MLGT based RC method can achieve much better R-D performances, quality smoothness, bit rate accuracy, buffer control results and subjective visual quality than the other state-of-the-art one-pass RC methods, and the achieved R-D performances are very close to the performance limits from the FixedQP method.

  12. Learning rate and attractor size of the single-layer perceptron

    International Nuclear Information System (INIS)

    Singleton, Martin S.; Huebler, Alfred W.

    2007-01-01

    We study the simplest possible order one single-layer perceptron with two inputs, using the delta rule with online learning, in order to derive closed form expressions for the mean convergence rates. We investigate the rate of convergence in weight space of the weight vectors corresponding to each of the 14 out of 16 linearly separable rules. These vectors follow zigzagging lines through the piecewise constant vector field to their respective attractors. Based on our studies, we conclude that a single-layer perceptron with N inputs will converge in an average number of steps given by an Nth order polynomial in (t/l), where t is the threshold, and l is the size of the initial weight distribution. Exact values for these averages are provided for the five linearly separable classes with N=2. We also demonstrate that the learning rate is determined by the attractor size, and that the attractors of a single-layer perceptron with N inputs partition R N +R N

  13. Do apolipoprotein E genotype and educational attainment predict the rate of cognitive decline in normal aging? A 12-year follow-up of the Maastricht Aging Study.

    Science.gov (United States)

    Van Gerven, Pascal W M; Van Boxtel, Martin P J; Ausems, Eleonora E B; Bekers, Otto; Jolles, Jelle

    2012-07-01

    We investigated suspected longitudinal interaction effects of apolipoprotein E (APOE) genotype and educational attainment on cognitive decline in normal aging. Our sample consisted of 571 healthy, nondemented adults aged between 49 and 82 years. Linear mixed-models analyses were performed with four measurement time points: baseline, 3-year, 6-year, and 12-year follow-up. Covariates included age at baseline, sex, and self-perceived physical and mental health. Dependent measures were global cognitive functioning (Mini-Mental State Examination; Folstein, Folstein, & McHugh, 1975), Stroop performance (Stroop Color-Word Test; Van der Elst, Van Boxtel, Van Breukelen, & Jolles, 2006a), set-shifting performance (Concept Shifting Test; Van der Elst, Van Boxtel, Van Breukelen, & Jolles, 2006b), cognitive speed (Letter-Digit Substitution Test; Van der Elst, Van Boxtel, Van Breukelen, & Jolles, 2006c), verbal learning (Verbal Learning Test: Sum of five trials; Van der Elst, Van Boxtel, Van Breukelen, & Jolles, 2005), and long-term memory (Verbal Learning Test: Delayed recall). We found only faint evidence that older, high-educated carriers of the APOE-ε4 allele (irrespective of zygosity) show a more pronounced decline than younger, low-educated carriers and noncarriers (irrespective of educational attainment). Moreover, this outcome was confined to concept-shifting performance and was especially observable between 6- and 12-year follow-ups. No protective effects of higher education were found on any of the six cognitive measures. We conclude that the combination of APOE-ε4 allele and high educational attainment may be a risk factor for accelerated cognitive decline in older age, as has been reported before, but only to a very limited extent. Moreover, we conclude that, within the cognitive reserve framework, education does not have significant protective power against age-related cognitive decline.

  14. New age- and sex-specific criteria for QT prolongation based on rate correction formulas that minimize bias at the upper normal limits.

    Science.gov (United States)

    Rautaharju, Pentti M; Mason, Jay W; Akiyama, Toshio

    2014-07-01

    Existing formulas for rate-corrected QT (QTc) commonly fail to properly adjust the upper normal limits which are more critical than the mean QTc for evaluation of prolonged QT. Age- and sex-related differences in QTc are also often overlooked. Our goal was to establish criteria for prolonged QTc using formulas that minimize QTc bias at the upper normal limits. Strict criteria were used in selecting a study group of 57,595 persons aged 5 to 89 years (54% women) and to exclude electrocardiograms (ECG) with possible disease-associated changes. Two QT rate adjustment formulas were identified which both minimized rate-dependency in the 98 th percentile limits: QTcmod, based on an electrophysiological model (QTcMod = QTx(120 + HR)/180)), and QTcLogLin, a power function of the RR interval with exponents 0.37 for men and 0.38 for women. QTc shortened in men during adolescence and QTcMod became 13 ms shorter than in women at age 20-29 years. The sex difference was maintained through adulthood although decreasing with age. The criteria established for prolonged QTc were: Age < 40 years, men 430 ms, women 440 ms; Age 40 to 69, men 440 ms, women 450 ms; Age ≥ 70 years, men 455 ms, and women 460 ms. Sex difference in QTc originates from shortened QT in adolescent males. Upper normal limits for QTc vary substantially by age and sex, and it is essential to use age- and sex-specific criteria for evaluation of QT prolongation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  15. Use of Sine Shaped High-Frequency Rhythmic Visual Stimuli Patterns for SSVEP Response Analysis and Fatigue Rate Evaluation in Normal Subjects

    Directory of Open Access Journals (Sweden)

    Ahmadreza Keihani

    2018-05-01

    Full Text Available Background: Recent EEG-SSVEP signal based BCI studies have used high frequency square pulse visual stimuli to reduce subjective fatigue. However, the effect of total harmonic distortion (THD has not been considered. Compared to CRT and LCD monitors, LED screen displays high-frequency wave with better refresh rate. In this study, we present high frequency sine wave simple and rhythmic patterns with low THD rate by LED to analyze SSVEP responses and evaluate subjective fatigue in normal subjects.Materials and Methods: We used patterns of 3-sequence high-frequency sine waves (25, 30, and 35 Hz to design our visual stimuli. Nine stimuli patterns, 3 simple (repetition of each of above 3 frequencies e.g., P25-25-25 and 6 rhythmic (all of the frequencies in 6 different sequences e.g., P25-30-35 were chosen. A hardware setup with low THD rate (<0.1% was designed to present these patterns on LED. Twenty two normal subjects (aged 23–30 (25 ± 2.1 yrs were enrolled. Visual analog scale (VAS was used for subjective fatigue evaluation after presentation of each stimulus pattern. PSD, CCA, and LASSO methods were employed to analyze SSVEP responses. The data including SSVEP features and fatigue rate for different visual stimuli patterns were statistically evaluated.Results: All 9 visual stimuli patterns elicited SSVEP responses. Overall, obtained accuracy rates were 88.35% for PSD and > 90% for CCA and LASSO (for TWs > 1 s. High frequency rhythmic patterns group with low THD rate showed higher accuracy rate (99.24% than simple patterns group (98.48%. Repeated measure ANOVA showed significant difference between rhythmic pattern features (P < 0.0005. Overall, there was no significant difference between the VAS of rhythmic [3.85 ± 2.13] compared to the simple patterns group [3.96 ± 2.21], (P = 0.63. Rhythmic group had lower within group VAS variation (min = P25-30-35 [2.90 ± 2.45], max = P35-25-30 [4.81 ± 2.65] as well as least individual pattern VAS (P25

  16. Effect of 3-substituted 1,4-benzodiazepin-2-ones on maximal normalized rate of bradykinin-induced smooth muscle contraction in the presence of calcium channel blockers

    Directory of Open Access Journals (Sweden)

    P. A. Virych

    2017-05-01

    Full Text Available The development of modern organic chemistry and molecular modeling technologies simplify the search for potential inhibitors of various receptor systems and biological processes. The one of the directions is the development of analgesics of broad spectrum and low toxicity. It is important to search for inhibitors of the kinin-kallikrein system that regulates many functions: inflammation, pain, carcinogenesis, vascular tone, smooth muscle contraction and other. Derivatives of 3-substituted 1,4-benzodiazepine-2-ones have a unique spatial conformation that allows one to simulate β-structures of bioactive peptides. The functional activity of compounds is determined by properties of their peripheral chemical radicals. We analyzed the effect of 3-substituted 1,4-benzodiazepin-2-ones derivatives on the normalized maximal rate of bradykinin-induced smooth muscle contraction and relaxation of the stomach in the presence of calcium channel blockers: verapamil (1 μM, gadolinium (300 μM and 2-aminoethyl diphenylborinate (0.1 μM. The levels of bradykinin and 3-arylamino-1,2-dihydro-3H-1,4-benzodiazepine-2-ones in incubation solution were 10–6 M. Data processing on dynamics of contraction was performed according to the method of Burdyha and Kosterin. Compounds MX-1775 and MX-1925 reduced maximal normalized rate (Vn of bradykinin-induced smooth muscle contraction in the presence of Gd3+ by 21.2% and 31.0% respectively. Compound MX-1925 increased Vn of relaxation by 11.6%. A similar effect is typical for MX-2011, where there is an increase by 34.6%. In the presence of verapamil this compound additionally decreased Vn contraction by 20.5%. Substances MX-1775, MX-2004 and MX-1925 restored maximal normalized rate of relaxation to original values of bradykinin-induced contraction. In the presence of 2-aminoethyldiphenylborinate MX-1775 additionally reduced Vn of contractions by 7.5%. 3-substituted 1,4-benzo­diazepine-2-ones did not change the maximal

  17. Comparison of Reversal Test Pictures among Three Groups of Students: Normal, Education Mental Retarded and Students with Learning Disabilities in Tehran

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Koushesh

    2007-01-01

    Full Text Available Objective: Riversal visual perception discrimination test is one of the dyslexia diagnostic tests in children which can be performed in the group (group-based and it is reliable to detect these disorders in students of the primary schools especially those who spend their first educational weeks or months. The aim of this survey is comparison of Riversal test pictures among three groups of students: normal, educable mental retarded students and students with learning disabilities, aged 8-12 years old that were under coverage of Tehran Welfare Department. Materials & Methods: This Comparative cross – sectional study has performed on 150 girls and boys of mentioned groups that were selected by simple randomize selection. Results: The findings suggested that there was significant difference between surveyed groups (P=0.001. The highest scores were related to normal students and the lowest scores to educable mental retarded. The interval of negative scores of educable mental retarded from normal students was more than that of between educable mental retarded and learning disabilities. Conclusion: This survey indicates that students with learning disabilities (dyslexia have problems in their visual perception and this test can help to diagnose and determine abnormal children as soon as possible in order to better treatment.

  18. A New Approach of an Intelligent E-Learning System Based on Learners' Skill Level and Learners' Success Rate

    Science.gov (United States)

    Mohamed, Hafidi; Lamia, Mahnane

    2015-01-01

    Learners usually meet cognitive overload and disorientation problems when using e-learning system. At present, most of the studies in e-learning either concentrate on the technological aspect or focus on adapting learner's interests or browsing behaviors, while, learner's skill level and learners' success rate is usually neglected. In this paper,…

  19. Adult Learner Graduation Rates at Four U.S. Community Colleges by Prior Learning Assessment Status and Method

    Science.gov (United States)

    Hayward, Milan S.; Williams, Mitchell R.

    2015-01-01

    The completion agenda demands higher community college graduation rates among adult learners, and prior learning assessment (PLA) is a promising solution. PLA permits students to earn credit for college-level learning acquired outside of higher education and is associated with improved student outcomes. However, little is known regarding community…

  20. Effect of Modifying Intervention Set Size with Acquisition Rate Data among Students Identified with a Learning Disability

    Science.gov (United States)

    Haegele, Katherine; Burns, Matthew K.

    2015-01-01

    The amount of information that students can successfully learn and recall at least 1 day later is called an acquisition rate (AR) and is unique to the individual student. The current study extended previous drill rehearsal research with word recognition by (a) using students identified with a learning disability in reading, (b) assessing set sizes…

  1. Policy learning for flood mitigation: a longitudinal assessment of the community rating system in Florida.

    Science.gov (United States)

    Brody, Samuel D; Zahran, Sammy; Highfield, Wesley E; Bernhardt, Sarah P; Vedlitz, Arnold

    2009-06-01

    Floods continue to inflict the most damage upon human communities among all natural hazards in the United States. Because localized flooding tends to be spatially repetitive over time, local decisionmakers often have an opportunity to learn from previous events and make proactive policy adjustments to reduce the adverse effects of a subsequent storm. Despite the importance of understanding the degree to which local jurisdictions learn from flood risks and under what circumstances, little if any empirical, longitudinal research has been conducted along these lines. This article addresses the research gap by examining the change in local flood mitigation policies in Florida from 1999 to 2005. We track 18 different mitigation activities organized into four series of activities under the Federal Emergency Management Agency's (FEMA) Community Rating System (CRS) for every local jurisdiction in Florida participating in the FEMA program on a yearly time step. We then identify the major factors contributing to policy changes based on CRS scores over the seven-year study period. Using multivariate statistical models to analyze both natural and social science data, we isolate the effects of several variables categorized into the following groups: hydrologic conditions, flood disaster history, socioeconomic and human capital controls. Results indicate that local jurisdictions do in fact learn from histories of flood risk and this process is expedited under specific conditions.

  2. Normal expiratory flow rate and lung volumes in patients with combined emphysema and interstitial lung disease: a case series and literature review.

    Science.gov (United States)

    Heathcote, Karen L; Cockcroft, Donald W; Fladeland, Derek A; Fenton, Mark E

    2011-01-01

    Pulmonary function tests in patients with idiopathic pulmonary fibrosis characteristically show a restrictive pattern including small lung volumes and increased expiratory flow rates resulting from a reduction in pulmonary compliance due to diffuse fibrosis. Conversely, an obstructive pattern with hyperinflation results in emphysema by loss of elastic recoil, expiratory collapse of the peripheral airways and air trapping. When the diseases coexist, pulmonary volumes are compensated, and a smaller than expected reduction or even normal lung volumes can be found. The present report describes 10 patients with progressive breathlessness, three of whom experienced severe limitation in their quality of life. All patients showed lung interstitial involvement and emphysema on computed tomography scan of the chest. The 10 patients showed normal spirometry and lung volumes with severe compromise of gas exchange. Normal lung volumes do not exclude diagnosis of idiopathic pulmonary fibrosis in patients with concomitant emphysema. The relatively preserved lung volumes may underestimate the severity of idiopathic pulmonary fibrosis and attenuate its effects on lung function parameters.

  3. Normal Expiratory Flow Rate and Lung Volumes in Patients with Combined Emphysema and Interstitial Lung Disease: A Case Series and Literature Review

    Directory of Open Access Journals (Sweden)

    Karen L Heathcote

    2011-01-01

    Full Text Available Pulmonary function tests in patients with idiopathic pulmonary fibrosis characteristically show a restrictive pattern including small lung volumes and increased expiratory flow rates resulting from a reduction in pulmonary compliance due to diffuse fibrosis. Conversely, an obstructive pattern with hyperinflation results in emphysema by loss of elastic recoil, expiratory collapse of the peripheral airways and air trapping. When the diseases coexist, pulmonary volumes are compensated, and a smaller than expected reduction or even normal lung volumes can be found. The present report describes 10 patients with progressive breathlessness, three of whom experienced severe limitation in their quality of life. All patients showed lung interstitial involvement and emphysema on computed tomography scan of the chest. The 10 patients showed normal spirometry and lung volumes with severe compromise of gas exchange. Normal lung volumes do not exclude diagnosis of idiopathic pulmonary fibrosis in patients with concomitant emphysema. The relatively preserved lung volumes may underestimate the severity of idiopathic pulmonary fibrosis and attenuate its effects on lung function parameters.

  4. Investigation of analytical methods in thermal stratification analysis. Evaluation of flow rates through flow holes for normal and scram conditions of 40% power operation with AQUA code

    International Nuclear Information System (INIS)

    Doi, Yoshihiro; Muramatsu, Toshiharu

    1997-08-01

    Thermal stratification phenomena are observed in an upper plenum of liquid metal fast breeder reactors (LMFBRs) under reactor scram conditions, which give rise to thermal stress on structural components. Therefore it is important to evaluate characteristics of phenomena in the design of the internal structure in an LMFBR plenum. To evaluate flow rates through flow holes of the prototype fast breeder reactor, MONJU, numerical analyses were carried out with AQUA code for normal and scram conditions with 40% power operation. Through comparison of analysis results and measured temperature, thermal stratification phenomena in 300 second period after the scram was evaluated. Flow rate through the upper flow holes, the lower flow holes and annular gap between the inner barrel and the reactor vessel were evaluated with the measured temperature and the analysis results individually. (J.P.N.)

  5. Perception of a Sung Vowel as a Function of Frequency-Modulation Rate and Excursionin Normal-Hearing and Hearing-Impaired Listeners

    DEFF Research Database (Denmark)

    Vatti, Marianna; Santurette, Sébastien; Pontoppidan, Niels henrik

    2014-01-01

    Purpose: Frequency fluctuations in human voices can usually be described as coherent frequency modulation (FM). As listeners with hearing impairment (HI listeners) are typically less sensitive to FM than listeners with normal hearing (NH listeners), this study investigated whether hearing loss...... affects the perception of a sung vowel based on FM cues. Method: Vibrato maps were obtained in 14 NH and 12 HI listeners with different degrees of musical experience. The FM rate and FM excursion of a synthesized vowel, to which coherent FM was applied, were adjusted until a singing voice emerged. Results......: In NH listeners, adding FM to the steady vowel components produced perception of a singing voice for FM rates between 4.1 and 7.5 Hz and FM excursions between 17 and 83 cents on average. In contrast, HI listeners showed substantially broader vibrato maps. Individual differences in map boundaries were...

  6. Shear rate normalization is not essential for removing the dependency of flow-mediated dilation on baseline artery diameter: past research revisited

    International Nuclear Information System (INIS)

    Atkinson, Greg

    2014-01-01

    A ratio index (FMD%) is used ubiquitously to scale (by simple division) brachial artery flow-mediated dilation (D diff ) in direct proportion to baseline diameter (D base ). It is now known that D diff is inversely proportional to D base rendering FMD% wholly inappropriate. Consequently, FMD% is still substantially dependent on D base . Although this problem is grounded in statistics, normalization of FMD% for the change in arterial shear rate (ΔSR) has been proposed to remove this D base -dependency. It was hypothesized that, if the flow-mediated response is scaled properly to D base in the first place, shear rate normalization would not be needed to remove D base -dependency. Dedicated software (Digitizelt) was employed to extract the data from a seminal study on FMD% normalization. The underlying allometric relationship between D base and peak diameter (D peak ) was described. The re-analyses revealed that the absolute change in arterial diameter was strongly inversely proportional to D base (r= − 0.7, P < 0.0005). The allometric exponent for the D base –D peak relationship was 0.82 (95% CI: 0.78–0.86) rather than the value of 1 needed for appropriate use of FMD%. The allometric approach completely eliminated the originally reported dependency on D base without any need for ΔSR normalization (r=0.0, P=0.96). The correlation between ΔSR and FMD% reduced from 0.69 to 0.37, when adjusted for D base . In conclusion, this new re-analysis of data from an influential study demonstrates that the FMD%–D base correlation is caused by the inappropriate size-scaling properties of FMD% itself. Removal of D base -dependency via FMD%/ΔSR normalization is not essential at all if allometric scaling is applied to isolate the flow-mediated response in the first place. Consequently, the influence of ΔSR on this properly scaled response can also be isolated and quantified accurately without the confounding influence of D base . (paper)

  7. Chaos Synchronization Using Adaptive Dynamic Neural Network Controller with Variable Learning Rates

    Directory of Open Access Journals (Sweden)

    Chih-Hong Kao

    2011-01-01

    Full Text Available This paper addresses the synchronization of chaotic gyros with unknown parameters and external disturbance via an adaptive dynamic neural network control (ADNNC system. The proposed ADNNC system is composed of a neural controller and a smooth compensator. The neural controller uses a dynamic RBF (DRBF network to online approximate an ideal controller. The DRBF network can create new hidden neurons online if the input data falls outside the hidden layer and prune the insignificant hidden neurons online if the hidden neuron is inappropriate. The smooth compensator is designed to compensate for the approximation error between the neural controller and the ideal controller. Moreover, the variable learning rates of the parameter adaptation laws are derived based on a discrete-type Lyapunov function to speed up the convergence rate of the tracking error. Finally, the simulation results which verified the chaotic behavior of two nonlinear identical chaotic gyros can be synchronized using the proposed ADNNC scheme.

  8. Use of Sine Shaped High-Frequency Rhythmic Visual Stimuli Patterns for SSVEP Response Analysis and Fatigue Rate Evaluation in Normal Subjects.

    Science.gov (United States)

    Keihani, Ahmadreza; Shirzhiyan, Zahra; Farahi, Morteza; Shamsi, Elham; Mahnam, Amin; Makkiabadi, Bahador; Haidari, Mohsen R; Jafari, Amir H

    2018-01-01

    Background: Recent EEG-SSVEP signal based BCI studies have used high frequency square pulse visual stimuli to reduce subjective fatigue. However, the effect of total harmonic distortion (THD) has not been considered. Compared to CRT and LCD monitors, LED screen displays high-frequency wave with better refresh rate. In this study, we present high frequency sine wave simple and rhythmic patterns with low THD rate by LED to analyze SSVEP responses and evaluate subjective fatigue in normal subjects. Materials and Methods: We used patterns of 3-sequence high-frequency sine waves (25, 30, and 35 Hz) to design our visual stimuli. Nine stimuli patterns, 3 simple (repetition of each of above 3 frequencies e.g., P25-25-25) and 6 rhythmic (all of the frequencies in 6 different sequences e.g., P25-30-35) were chosen. A hardware setup with low THD rate ( 90% for CCA and LASSO (for TWs > 1 s). High frequency rhythmic patterns group with low THD rate showed higher accuracy rate (99.24%) than simple patterns group (98.48%). Repeated measure ANOVA showed significant difference between rhythmic pattern features ( P rhythmic [3.85 ± 2.13] compared to the simple patterns group [3.96 ± 2.21], ( P = 0.63). Rhythmic group had lower within group VAS variation (min = P25-30-35 [2.90 ± 2.45], max = P35-25-30 [4.81 ± 2.65]) as well as least individual pattern VAS (P25-30-35). Discussion and Conclusion: Overall, rhythmic and simple pattern groups had higher and similar accuracy rates. Rhythmic stimuli patterns showed insignificantly lower fatigue rate than simple patterns. We conclude that both rhythmic and simple visual high frequency sine wave stimuli require further research for human subject SSVEP-BCI studies.

  9. Cultured cells from a severe combined immunodeficient mouse have a slower than normal rate of repair of potentially lethal damage sensitive to hypertonic treatment

    International Nuclear Information System (INIS)

    Kimura, H.; Terado, T.; Ikebuchi, M.; Aoyama, T.; Komatsu, K.; Nozawa, A.

    1995-01-01

    The effects of hypertonic 0.5 M NaCl treatment after irradiation on the repair of DNA damage were examined in fibroblasts of the severe combined immunodeficient (scid) mouse. These cells are hypersensitive to ionizing radiation because of a deficiency in the repair of double-strand breaks. Hypertonic treatment caused radiosensitization due to a fixation of potentially lethal damage (PLD) in scid cells, demonstrating that scid cells normally repair PLD. To assess the kinetics of the repair of PLD, hypertonic treatment was delayed for various times after irradiation. Potentially lethal damage was repaired during these times in isotonic medium at 37 degrees C. It was found that the rate of repair of PLD was much slower in scid cells than in BALB/c 3T3 cells, which have a open-quotes wild-typeclose quotes level of radiosensitivity. This fact indicates that the scid mutation affects the type of repair of PLD that is sensitive to 0.5 M NaCl treatment. In scid hybrid cells containing fragments of human chromosome 8, which complements the radiosensitivity of the scid cells, the rate of repair was restored to a normal level. An enzyme encoded by a gene on chromosome 8 may also be connected with PLD which is sensitive to hypertonic treatment. 29 refs., 3 figs

  10. Residual learning rates in lead-acid batteries: Effects on emerging technologies

    International Nuclear Information System (INIS)

    Matteson, Schuyler; Williams, Eric

    2015-01-01

    The low price of lead-acid, the most popular battery, is often used in setting cost targets for emerging energy storage technologies. Future cost reductions in lead acid batteries could increase investment and time scales needed for emerging storage technologies to reach cost-parity. In this paper the first documented model of cost reductions for lead-acid batteries is developed. Regression to a standard experience curve using 1989–2012 data yield a poor fit, with R 2 values of 0.17 for small batteries and 0.05 for larger systems. To address this problem, battery costs are separated into material and residual costs, and experience curves developed for residual costs. Depending on the year, residual costs account for 41–86% of total battery cost. Using running-time averages to address volatility in material costs, a 4-year time average experience curve for residual costs yield much higher R 2 , 0.78 for small and 0.74 for large lead-acid batteries. The learning rate for residual costs in lead-acid batteries is 20%, a discovery with policy implications. Neglecting to consider cost reductions in lead-acid batteries could result in failure of energy storage start-ups and public policy programs. Generalizing this result, learning in incumbent technologies must be understood to assess the potential of emerging ones. -- Highlights: •We analyze potential cost reductions in lead-acid batteries. •Modified experience curve for non-material costs gives good empirical fit. •Historical learning rate for non-material costs from 1985–2012 is 19–24%. •Progress in incumbent technology raises barrier to new entrants

  11. Acetylcholine Neuromodulation in Normal and Abnormal Learning and Memory: Vigilance Control in Waking, Sleep, Autism, Amnesia and Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Stephen Grossberg

    2017-11-01

    Full Text Available Adaptive Resonance Theory, or ART, is a neural model that explains how normal and abnormal brains may learn to categorize and recognize objects and events in a changing world, and how these learned categories may be remembered for a long time. This article uses ART to propose and unify the explanation of diverse data about normal and abnormal modulation of learning and memory by acetylcholine (ACh. In ART, vigilance control determines whether learned categories will be general and abstract, or specific and concrete. ART models how vigilance may be regulated by ACh release in layer 5 neocortical cells by influencing after-hyperpolarization (AHP currents. This phasic ACh release is mediated by cells in the nucleus basalis (NB of Meynert that are activated by unexpected events. The article additionally discusses data about ACh-mediated tonic control of vigilance. ART proposes that there are often dynamic breakdowns of tonic control in mental disorders such as autism, where vigilance remains high, and medial temporal amnesia, where vigilance remains low. Tonic control also occurs during sleep-wake cycles. Properties of Up and Down states during slow wave sleep arise in ACh-modulated laminar cortical ART circuits that carry out processes in awake individuals of contrast normalization, attentional modulation, decision-making, activity-dependent habituation, and mismatch-mediated reset. These slow wave sleep circuits interact with circuits that control circadian rhythms and memory consolidation. Tonic control properties also clarify how Alzheimer’s disease symptoms follow from a massive structural degeneration that includes undermining vigilance control by ACh in cortical layers 3 and 5. Sleep disruptions before and during Alzheimer’s disease, and how they contribute to a vicious cycle of plaque formation in layers 3 and 5, are also clarified from this perspective.

  12. Insulin production rate in normal man as an estimate for calibration of continuous intravenous insulin infusion in insulin-dependent diabetic patients.

    Science.gov (United States)

    Waldhäusl, W K; Bratusch-Marrain, P R; Francesconi, M; Nowotny, P; Kiss, A

    1982-01-01

    This study examines the feasibility of deriving the 24-h insulin requirement of insulin-dependent diabetic patients who were devoid of any endogenous insulin release (IDD) from the insulin-production rate (IPR) of healthy man (basal, 17 mU/min; stimulated 1.35 U/12.5 g glucose). To this end, continuous intravenous insulin infusion (CIVII) was initiated at a precalculated rate of 41.2 +/- 4.6 (SD) U/24 h in IDD (N - 12). Blood glucose profiles were compared with those obtained during intermittent subcutaneous (s.c.) insulin therapy (IIT) and those of healthy controls (N = 7). Regular insulin (Hoechst CS) was infused with an adapted Mill Hill Infuser at a basal infusion rate of 1.6 U/h (6:00 a.m. to 8:00 p.m.), and of 0.8 U/h from 8:00 p.m. to 6:00 a.m. Preprandial insulin (3.2-6.4 U) was added for breakfast, lunch, and dinner. Daily individual food intake totaled 7688 +/- 784 kJ (1836 +/- 187 kcal)/24 h including 184 +/- 37 g of glucose. Proper control of blood glucose (BG) (mean BG 105 +/- 10 mg/dl; mean amplitude of glycemic excursions 54 +/- 18 mg/dl; and 1 h postprandial BG levels not exceeding 160 mg/dl) and of plasma concentrations of beta-hydroxybutyrate and lactate was maintained by 41.4 +/- 4.4 U insulin/24 h. Although BG values only approximated the upper normal range as seen in healthy controls, they were well within the range reported by others during CIVII. Therefore, we conclude that in adult IDD completely devoid of endogenous insulin (1) the IPR of normal man can be used during CIVII as an estimate for the patient's minimal insulin requirement per 24 h, and (2) this approach allows for a blood glucose profile close to the upper range of a normal control group. Thus, deriving a patient's daily insulin dose from the insulin production rate of healthy man may add an additional experimental protocol which aids in making general calculations of a necessary insulin dose instead of using trial and error or a closed-loop insulin infusion system.

  13. Volatility forecasting for interbank offered rate using grey extreme learning machine: The case of China

    International Nuclear Information System (INIS)

    Liu, Xiaoyong; Fu, Hui

    2016-01-01

    Interbank Offered rate is the only direct market rate in China’s currency market. Volatility forecasting of China Interbank Offered Rate (IBOR) has a very important theoretical and practical significance for financial asset pricing and financial risk measure or management. However, IBOR is a dynamics and non-steady time series whose developmental changes have stronger random fluctuation, so it is difficult to forecast the volatility of IBOR. This paper offers a hybrid algorithm using grey model and extreme learning machine (ELM) to forecast volatility of IBOR. The proposed algorithm is composed of three phases. In the first, grey model is used to deal with the original IBOR time series by accumulated generating operation (AGO) and weaken the stochastic volatility in original series. And then, a forecasting model is founded by using ELM to analyze the new IBOR series. Lastly, the predictive value of the original IBOR series can be obtained by inverse accumulated generating operation (IAGO). The new model is applied to forecasting Interbank Offered Rate of China. Compared with the forecasting results of BP and classical ELM, the new model is more efficient to forecasting short- and middle-term volatility of IBOR.

  14. Heterogeneous Information about the Term Structure of Interest rates, Least-Squares Learning and Optimal Interest Rate Rules for Inflation Forecast Targeting

    NARCIS (Netherlands)

    Schaling, E.; Eijffinger, S.C.W.; Tesfaselassie, M.F.

    2004-01-01

    In this paper we incorporate the term structure of interest rates in a standard inflation forecast targeting framework.Learning about the transmission process of monetary policy is introduced by having heterogeneous agents - i.e. the central bank and private agents - who have different information

  15. Optimization of Korean energy planning for sustainability considering uncertainties in learning rates and external factors

    International Nuclear Information System (INIS)

    Kim, Seunghyok; Koo, Jamin; Lee, Chang Jun; Yoon, En Sup

    2012-01-01

    During the last few decades, energy planning has focused on meeting domestic demand at lower total costs. However, global warming and the shared recognition of it have transformed the problem of energy planning into a more complex task with a greater number of issues to be considered. Since the key issue is to reduce greenhouse effects, governments around the world have begun to make investments in renewable energy systems (e.g., hydro, wind, solar, and/or biomass power). The relatively high costs of renewable energy systems and the uncertain outlook of their rate of diffusion in the market make it difficult to heavily rely on them. The uncertain variations in production cost over time are especially challenging. To handle uncertainties, the concept of the learning rate was adopted in this study so as to compute the costs of energy systems in the future and Monte Carlo simulation was performed. The aim of this study was to optimize plans of conventional and prospective renewable energy systems with respect to production cost. The production cost included capital, fixed, variable, and external costs. For the case study, the energy situation in South Korea was used. The results of the case study where the proposed methodology was applied could provide useful insights economically and strategies of sustainable energy management for ambiguous environments. -- Highlights: ► We propose energy planning method for sustainability. ► We consider uncertainties such as learning rate, fuel prices, and CO 2 prices. ► We consider the possibility of CO 2 trading. ► The proposed method is applied to South Korea case. ► The added capacities of energy systems depend on uncertainties.

  16. VALUATION OF THE BLOG LIKE REVITALIZING WAY OF PROCESSES OF EDUCATION-LEARNING IN THE NORMAL EDUCATION

    Directory of Open Access Journals (Sweden)

    María Isabel Ramírez-Ochoa

    2016-07-01

    Full Text Available The article shares the results of the intervention Project blog called “Proyecto de lectura y escritura, ENEF” as an educational technological media to transform traditional learning environment of the course "Reading and Writing Workshop", during the 2012-1 school year, the group student educator form second semester. With this educational initiative is intended to 50 students use this technological medium as support in the process of teaching and learning. The investigation began with diagnosed digital skills as much as teachers, like students. Subsequently, the behavior of the teacher and the group blog was analyzed. The results demonstrate the usefulness of this technology as a catalyst for learning processes.

  17. The Serine Protease Inhibitor Neuroserpin Is Required for Normal Synaptic Plasticity and Regulates Learning and Social Behavior

    Science.gov (United States)

    Reumann, Rebecca; Vierk, Ricardo; Zhou, Lepu; Gries, Frederice; Kraus, Vanessa; Mienert, Julia; Romswinkel, Eva; Morellini, Fabio; Ferrer, Isidre; Nicolini, Chiara; Fahnestock, Margaret; Rune, Gabriele; Glatzel, Markus; Galliciotti, Giovanna

    2017-01-01

    The serine protease inhibitor neuroserpin regulates the activity of tissue-type plasminogen activator (tPA) in the nervous system. Neuroserpin expression is particularly prominent at late stages of neuronal development in most regions of the central nervous system (CNS), whereas it is restricted to regions related to learning and memory in the…

  18. "It's Not Like a Normal 9 to 5!": The Learning Journeys of Media Production Apprentices in Distributed Working Conditions

    Science.gov (United States)

    Lahiff, Ann; Guile, David

    2016-01-01

    An apprenticeship in media production in England is at the centre of this case study exploration. The context is exemplified by the organisation of the process of production around project teams and the development of project-based working cultures. Given these developments, the working conditions and learning opportunities presented to…

  19. Rate of transformation and normal range about cardiac size and cardiothoracic ratio according to patient position and age at chest radiography of Korean adult man

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Young Cheol [Dept. of Radiology, Samsung Medical Center, Seoul (Korea, Republic of); Lim, Cheong Hwan; Jung, Hong Ryang [Dept. of Radiological Science, Hanseo University, Seosan (Korea, Republic of); Kim, Yun Min [Dept. of Radiotechnology, Wonkwang Health Science University, Iksan (Korea, Republic of); Hong, Dong Hee [Dept. of Radiological Science, Far East University, Eumseong (Korea, Republic of)

    2017-06-15

    Purpose of this study is present the normal range of cardiac size and cardiothoracic ratio according to patient position(chest PA and AP) and age of Korean adult male on digital chest X - ray, And to propose a mutually compatible conversion rate. 1,024 males were eligible for this study, among 1,300 normal chest patients who underwent chest PA and low-dose CT examinations on the same day at the 'S' Hospital Health Examination Center in Seoul From January to December 2014. CS and CTR were measured by Danzer (1919). The mean difference between CS and CTR was statistically significant (p<0.01) in Chest PA (CS 135.48 mm, CTR 43.99%) and Chest AP image (CS 155.96 mm, CTR 51.75%). There was no statistically significant difference between left and right heart in chest PA and AP images(p>0.05). CS showed statistically significant difference between Chest PA (p>0. 05) and Chest AP (p<0.05). The thorax size and CTR were statistically significant (p<0.01) in both age and chest PA and AP. Result of this study, On Chest AP image CS was magnified 15%, CTR was magnified 17% compare with Chest PA image. CS and CTR were about 10% difference by changing posture at all ages.

  20. The Effect of Incorporating Good Learners' Ratings in e-Learning Content-Based Recommender System

    Science.gov (United States)

    Ghauth, Khairil Imran; Abdullah, Nor Aniza

    2011-01-01

    One of the anticipated challenges of today's e-learning is to solve the problem of recommending from a large number of learning materials. In this study, we introduce a novel architecture for an e-learning recommender system. More specifically, this paper comprises the following phases i) to propose an e-learning recommender system based on…

  1. Learning visual balance from large-scale datasets of aesthetically highly rated images

    Science.gov (United States)

    Jahanian, Ali; Vishwanathan, S. V. N.; Allebach, Jan P.

    2015-03-01

    The concept of visual balance is innate for humans, and influences how we perceive visual aesthetics and cognize harmony. Although visual balance is a vital principle of design and taught in schools of designs, it is barely quantified. On the other hand, with emergence of automantic/semi-automatic visual designs for self-publishing, learning visual balance and computationally modeling it, may escalate aesthetics of such designs. In this paper, we present how questing for understanding visual balance inspired us to revisit one of the well-known theories in visual arts, the so called theory of "visual rightness", elucidated by Arnheim. We define Arnheim's hypothesis as a design mining problem with the goal of learning visual balance from work of professionals. We collected a dataset of 120K images that are aesthetically highly rated, from a professional photography website. We then computed factors that contribute to visual balance based on the notion of visual saliency. We fitted a mixture of Gaussians to the saliency maps of the images, and obtained the hotspots of the images. Our inferred Gaussians align with Arnheim's hotspots, and confirm his theory. Moreover, the results support the viability of the center of mass, symmetry, as well as the Rule of Thirds in our dataset.

  2. Impact of problem-based, active learning on graduation rates for 10 generations of Dutch medical students

    NARCIS (Netherlands)

    Schmidt, Henk G.; Cohen-Schotanus, Janke; Arends, Lidia R.

    We aimed to study the effects of active-learning curricula on graduation rates of students and on the length of time needed to graduate. Graduation rates for 10 generations of students enrolling in the eight Dutch medical schools between 1989 and 1998 were analysed. In addition, time needed to

  3. Empirically observed learning rates for concentrating solar power and their responses to regime change

    Science.gov (United States)

    Lilliestam, Johan; Labordena, Mercè; Patt, Anthony; Pfenninger, Stefan

    2017-07-01

    Concentrating solar power (CSP) capacity has expanded slower than other renewable technologies and its costs are still high. Until now, there have been too few CSP projects to derive robust conclusions about its cost development. Here we present an empirical study of the cost development of all operating CSP stations and those under construction, examining the roles of capacity growth, industry continuity, and policy support design. We identify distinct CSP expansion phases, each characterized by different cost pressure in the policy regime and different industry continuity. In 2008-2011, with low cost pressure and following industry discontinuity, costs increased. In the current phase, with high cost pressure and continuous industry development, costs decreased rapidly, with learning rates exceeding 20%. Data for projects under construction suggest that this trend is continuing and accelerating. If support policies and industrial structure are sustained, we see no near-term factors that would hinder further cost decreases.

  4. SU-E-T-501: Normal Tissue Toxicities of Pulsed Low Dose Rate Radiotherapy and Conventional Radiotherapy: An in Vivo Total Body Irradiation Study

    Energy Technology Data Exchange (ETDEWEB)

    Cvetkovic, D; Zhang, P; Wang, B; Chen, L; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States)

    2014-06-01

    Purpose: Pulsed low dose rate radiotherapy (PLDR) is a re-irradiation technique for therapy of recurrent cancers. We have previously shown a significant difference in the weight and survival time between the mice treated with conventional radiotherapy (CRT) and PLDR using total body irradiation (TBI). The purpose of this study was to investigate the in vivo effects of PLDR on normal mouse tissues.Materials and Methods: Twenty two male BALB/c nude mice, 4 months of age, were randomly assigned into a PLDR group (n=10), a CRT group (n=10), and a non-irradiated control group (n=2). The Siemens Artiste accelerator with 6 MV photon beams was used. The mice received a total of 18Gy in 3 fractions with a 20day interval. The CRT group received the 6Gy dose continuously at a dose rate of 300 MU/min. The PLDR group was irradiated with 0.2Gyx20 pulses with a 3min interval between the pulses. The mice were weighed thrice weekly and sacrificed 2 weeks after the last treatment. Brain, heart, lung, liver, spleen, gastrointestinal, urinary and reproductive organs, and sternal bone marrow were removed, formalin-fixed, paraffin-embedded and stained with H and E. Morphological changes were observed under a microscope. Results: Histopathological examination revealed atrophy in several irradiated organs. The degree of atrophy was mild to moderate in the PLDR group, but severe in the CRT group. The most pronounced morphological abnormalities were in the immune and hematopoietic systems, namely spleen and bone marrow. Brain hemorrhage was seen in the CRT group, but not in the PLDR group. Conclusions: Our results showed that PLDR induced less toxicity in the normal mouse tissues than conventional radiotherapy for the same dose and regimen. Considering that PLDR produces equivalent tumor control as conventional radiotherapy, it would be a good modality for treatment of recurrent cancers.

  5. SU-F-R-08: Can Normalization of Brain MRI Texture Features Reduce Scanner-Dependent Effects in Unsupervised Machine Learning?

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, K; O’Dwyer, R [SUNY Upstate Medical University, Syracuse, NY (United States); Bradford, T [Syracuse University, Syracuse, NY (United States); Cussen, L [Rochester Institute of Technology, Rochester, NY (United States)

    2016-06-15

    Purpose: To reduce differences in features calculated from MRI brain scans acquired at different field strengths with or without Gadolinium contrast. Methods: Brain scans were processed for 111 epilepsy patients to extract hippocampus and thalamus features. Scans were acquired on 1.5 T scanners with Gadolinium contrast (group A), 1.5T scanners without Gd (group B), and 3.0 T scanners without Gd (group C). A total of 72 features were extracted. Features were extracted from original scans and from scans where the image pixel values were rescaled to the mean of the hippocampi and thalami values. For each data set, cluster analysis was performed on the raw feature set and for feature sets with normalization (conversion to Z scores). Two methods of normalization were used: The first was over all values of a given feature, and the second by normalizing within the patient group membership. The clustering software was configured to produce 3 clusters. Group fractions in each cluster were calculated. Results: For features calculated from both the non-rescaled and rescaled data, cluster membership was identical for both the non-normalized and normalized data sets. Cluster 1 was comprised entirely of Group A data, Cluster 2 contained data from all three groups, and Cluster 3 contained data from only groups 1 and 2. For the categorically normalized data sets there was a more uniform distribution of group data in the three Clusters. A less pronounced effect was seen in the rescaled image data features. Conclusion: Image Rescaling and feature renormalization can have a significant effect on the results of clustering analysis. These effects are also likely to influence the results of supervised machine learning algorithms. It may be possible to partly remove the influence of scanner field strength and the presence of Gadolinium based contrast in feature extraction for radiomics applications.

  6. SU-F-R-08: Can Normalization of Brain MRI Texture Features Reduce Scanner-Dependent Effects in Unsupervised Machine Learning?

    International Nuclear Information System (INIS)

    Ogden, K; O’Dwyer, R; Bradford, T; Cussen, L

    2016-01-01

    Purpose: To reduce differences in features calculated from MRI brain scans acquired at different field strengths with or without Gadolinium contrast. Methods: Brain scans were processed for 111 epilepsy patients to extract hippocampus and thalamus features. Scans were acquired on 1.5 T scanners with Gadolinium contrast (group A), 1.5T scanners without Gd (group B), and 3.0 T scanners without Gd (group C). A total of 72 features were extracted. Features were extracted from original scans and from scans where the image pixel values were rescaled to the mean of the hippocampi and thalami values. For each data set, cluster analysis was performed on the raw feature set and for feature sets with normalization (conversion to Z scores). Two methods of normalization were used: The first was over all values of a given feature, and the second by normalizing within the patient group membership. The clustering software was configured to produce 3 clusters. Group fractions in each cluster were calculated. Results: For features calculated from both the non-rescaled and rescaled data, cluster membership was identical for both the non-normalized and normalized data sets. Cluster 1 was comprised entirely of Group A data, Cluster 2 contained data from all three groups, and Cluster 3 contained data from only groups 1 and 2. For the categorically normalized data sets there was a more uniform distribution of group data in the three Clusters. A less pronounced effect was seen in the rescaled image data features. Conclusion: Image Rescaling and feature renormalization can have a significant effect on the results of clustering analysis. These effects are also likely to influence the results of supervised machine learning algorithms. It may be possible to partly remove the influence of scanner field strength and the presence of Gadolinium based contrast in feature extraction for radiomics applications.

  7. Biomass Gasification. The characteristics of technology development and the rate of learning

    Energy Technology Data Exchange (ETDEWEB)

    Dorca Duch, Andreu; Huertas Bermejo, Javier

    2008-09-15

    Gasification is considered one of the most promising technologies in biomass applications. The higher efficiency compared to boiler power systems, the perspectives in fuel synthesis and its environmental friendly features are some examples of its potential. Biomass gasification has evolved since its first applications, but it has not been possible to reach a solid commercial stage, except during periods of crises and only for some specific applications. Meanwhile, other gasification technologies, fed by fossil fuels, are currently widely used on industrial scales. This thesis aims to analyze the knowledge development and diffusion patterns of the biomass gasification technology since 1970s in Austria, Finland, Germany and Sweden. Additionally, it seeks to identify the factors that strengthen and weaken the learning process. Finally, the concept of learning curve will be used to numerically assess the rate of learning in small scale biomass gasification for electricity generation. The feasibility of various future scenarios will be evaluated in order to know what is the likelihood for the technology to become competitive in the short term. To do so, the historical evolution of biomass gasification in Austria, Finland, Germany and Sweden has been analyzed. These countries have been selected due to the increasing number of ongoing projects and initiatives since 1970. Subsequently, the development of this technology has been encouraged by two historical facts. Initially, the price of fossil fuels grew in 1973 and 1979 enhancing the interest for biomass gasification as a future alternative. Afterwards, the willingness, shown by the mentioned countries, to reduce greenhouse gases emissions following the Kyoto protocol has revived the interest in biomass gasification. However, none of these two events has driven this technology sufficiently to achieve a sustainable commercial status. In addition, small and large scale projects have followed different development processes

  8. Audiovisual spoken word training can promote or impede auditory-only perceptual learning: prelingually deafened adults with late-acquired cochlear implants versus normal hearing adults.

    Science.gov (United States)

    Bernstein, Lynne E; Eberhardt, Silvio P; Auer, Edward T

    2014-01-01

    Training with audiovisual (AV) speech has been shown to promote auditory perceptual learning of vocoded acoustic speech by adults with normal hearing. In Experiment 1, we investigated whether AV speech promotes auditory-only (AO) perceptual learning in prelingually deafened adults with late-acquired cochlear implants. Participants were assigned to learn associations between spoken disyllabic C(=consonant)V(=vowel)CVC non-sense words and non-sense pictures (fribbles), under AV and then AO (AV-AO; or counter-balanced AO then AV, AO-AV, during Periods 1 then 2) training conditions. After training on each list of paired-associates (PA), testing was carried out AO. Across all training, AO PA test scores improved (7.2 percentage points) as did identification of consonants in new untrained CVCVC stimuli (3.5 percentage points). However, there was evidence that AV training impeded immediate AO perceptual learning: During Period-1, training scores across AV and AO conditions were not different, but AO test scores were dramatically lower in the AV-trained participants. During Period-2 AO training, the AV-AO participants obtained significantly higher AO test scores, demonstrating their ability to learn the auditory speech. Across both orders of training, whenever training was AV, AO test scores were significantly lower than training scores. Experiment 2 repeated the procedures with vocoded speech and 43 normal-hearing adults. Following AV training, their AO test scores were as high as or higher than following AO training. Also, their CVCVC identification scores patterned differently than those of the cochlear implant users. In Experiment 1, initial consonants were most accurate, and in Experiment 2, medial consonants were most accurate. We suggest that our results are consistent with a multisensory reverse hierarchy theory, which predicts that, whenever possible, perceivers carry out perceptual tasks immediately based on the experience and biases they bring to the task. We

  9. A single-rate context-dependent learning process underlies rapid adaptation to familiar object dynamics.

    Science.gov (United States)

    Ingram, James N; Howard, Ian S; Flanagan, J Randall; Wolpert, Daniel M

    2011-09-01

    Motor learning has been extensively studied using dynamic (force-field) perturbations. These induce movement errors that result in adaptive changes to the motor commands. Several state-space models have been developed to explain how trial-by-trial errors drive the progressive adaptation observed in such studies. These models have been applied to adaptation involving novel dynamics, which typically occurs over tens to hundreds of trials, and which appears to be mediated by a dual-rate adaptation process. In contrast, when manipulating objects with familiar dynamics, subjects adapt rapidly within a few trials. Here, we apply state-space models to familiar dynamics, asking whether adaptation is mediated by a single-rate or dual-rate process. Previously, we reported a task in which subjects rotate an object with known dynamics. By presenting the object at different visual orientations, adaptation was shown to be context-specific, with limited generalization to novel orientations. Here we show that a multiple-context state-space model, with a generalization function tuned to visual object orientation, can reproduce the time-course of adaptation and de-adaptation as well as the observed context-dependent behavior. In contrast to the dual-rate process associated with novel dynamics, we show that a single-rate process mediates adaptation to familiar object dynamics. The model predicts that during exposure to the object across multiple orientations, there will be a degree of independence for adaptation and de-adaptation within each context, and that the states associated with all contexts will slowly de-adapt during exposure in one particular context. We confirm these predictions in two new experiments. Results of the current study thus highlight similarities and differences in the processes engaged during exposure to novel versus familiar dynamics. In both cases, adaptation is mediated by multiple context-specific representations. In the case of familiar object dynamics

  10. A single-rate context-dependent learning process underlies rapid adaptation to familiar object dynamics.

    Directory of Open Access Journals (Sweden)

    James N Ingram

    2011-09-01

    Full Text Available Motor learning has been extensively studied using dynamic (force-field perturbations. These induce movement errors that result in adaptive changes to the motor commands. Several state-space models have been developed to explain how trial-by-trial errors drive the progressive adaptation observed in such studies. These models have been applied to adaptation involving novel dynamics, which typically occurs over tens to hundreds of trials, and which appears to be mediated by a dual-rate adaptation process. In contrast, when manipulating objects with familiar dynamics, subjects adapt rapidly within a few trials. Here, we apply state-space models to familiar dynamics, asking whether adaptation is mediated by a single-rate or dual-rate process. Previously, we reported a task in which subjects rotate an object with known dynamics. By presenting the object at different visual orientations, adaptation was shown to be context-specific, with limited generalization to novel orientations. Here we show that a multiple-context state-space model, with a generalization function tuned to visual object orientation, can reproduce the time-course of adaptation and de-adaptation as well as the observed context-dependent behavior. In contrast to the dual-rate process associated with novel dynamics, we show that a single-rate process mediates adaptation to familiar object dynamics. The model predicts that during exposure to the object across multiple orientations, there will be a degree of independence for adaptation and de-adaptation within each context, and that the states associated with all contexts will slowly de-adapt during exposure in one particular context. We confirm these predictions in two new experiments. Results of the current study thus highlight similarities and differences in the processes engaged during exposure to novel versus familiar dynamics. In both cases, adaptation is mediated by multiple context-specific representations. In the case of familiar

  11. A Learning Collaborative Model to Improve Human Papillomavirus Vaccination Rates in Primary Care.

    Science.gov (United States)

    Rand, Cynthia M; Tyrrell, Hollyce; Wallace-Brodeur, Rachel; Goldstein, Nicolas P N; Darden, Paul M; Humiston, Sharon G; Albertin, Christina S; Stratbucker, William; Schaffer, Stanley J; Davis, Wendy; Szilagyi, Peter G

    2018-03-01

    Human papillomavirus (HPV) vaccination rates remain low, in part because of missed opportunities (MOs) for vaccination. We used a learning collaborative quality improvement (QI) model to assess the effect of a multicomponent intervention on reducing MOs. Study design: pre-post using a QI intervention in 33 community practices and 14 pediatric continuity clinics over 9 months to reduce MOs for HPV vaccination at all visit types. outcome measures comprised baseline and postproject measures of 1) MOs (primary outcome), and 2) HPV vaccine initiation and completion. Process measures comprised monthly chart audits of MOs for HPV vaccination for performance feedback, monthly Plan-Do-Study-Act surveys and pre-post surveys about office systems. providers were trained at the start of the project on offering a strong recommendation for HPV vaccination. Practices implemented provider prompts and/or standing orders and/or reminder/recall if desired, and were provided monthly feedback on MOs to assess their progress. chi-square tests were used to assess changes in office practices, and logistic regression used to assess changes in MOs according to visit type and overall, as well as HPV vaccine initiation and completion. MOs overall decreased (from 73% to 53% in community practices and 62% to 55% in continuity clinics; P < .01, and P = .03, respectively). HPV vaccine initiation increased for both genders in community practices (from 66% to 74% for female, 57% to 65% for male; P < .01), and for male patients in continuity clinics (from 68% to 75%; P = .05). Series completion increased overall in community practices (39% to 43%; P = .04) and for male patients in continuity clinics (from 36% to 44%; P = .03). Office systems changes using a QI model and multicomponent interventions decreased rates of MO for HPV vaccination and increased initiation and completion rates among some gender subgroups. A learning collaborative model provides an effective forum for practices to

  12. The effect of chronic administration of Apium graveolens aqueous extract on learning and memory in normal and diabetic rats

    Directory of Open Access Journals (Sweden)

    Mehdad Roghani

    2009-01-01

    Full Text Available   Abstract   Introduction: Diabetes mellitus accompanies with disturbances in learning, memory, and cognitive skills in the human society and experimental animals. Considering the beneficial antidiabetic potential of Apium graveolens (AG , this research study was conducted to evaluate the effect of chronic i.p. administration of AG on learning and memory in diabetic rats using passive avoidance and Y-maze tests.   Methods: Female Wistar rats were randomly divided into control, AG-treated control, diabetic, and AG-treated diabetic groups. AG treatment continued for 4 weeks. For induction of diabetes, streptozotocin was injected i.p. at a single dose of 60 mg/kg. For evaluation of learning and memory, initial latency (IL and step-through latency (STL were determined at the end of study using passive avoidance test. Meanwhile, alternation behavior percentage was determined using Y maze. Results: There was a significant increase (p<0.05 in IL in diabetic and AG-treated diabetic groups after 4 weeks as compared to control group. In this respect, there was no significant difference between diabetic and AG-treated diabetic groups. On the other hand, STL significantly decreased (p<0.05 in diabetic group and significantly increased (p<0.05 in AG-treated diabetic group as compared to control group at the end of study. In addition, STL did not significantly change in AG-treated control group in comparison with control group. In addition, results of Y-maze test showed that there is no significant difference between diabetic and Ag-treated diabetic groups and between control and Ag-treated control group regarding alternation behavior. Discussion: In summary, chronic oral administration of AG could enhance the consolidation and recall capability of stored information only in diabetic animals and did not affect spatial memory of diabetic animals.  

  13. The effect of chronic administration of Apium graveolens aqueous extract on learning and memory in normal and diabetic rats

    Directory of Open Access Journals (Sweden)

    Mehdad Roghani

    2009-01-01

    Full Text Available Abstract   Introduction: Diabetes mellitus accompanies with disturbances in learning, memory, and cognitive skills in the human society and experimental animals. Considering the beneficial antidiabetic potential of Apium graveolens (AG , this research study was conducted to evaluate the effect of chronic i.p. administration of AG on learning and memory in diabetic rats using passive avoidance and Y-maze tests.   Methods: Female Wistar rats were randomly divided into control, AG-treated control, diabetic, and AG-treated diabetic groups. AG treatment continued for 4 weeks. For induction of diabetes, streptozotocin was injected i.p. at a single dose of 60 mg/kg. For evaluation of learning and memory, initial latency (IL and step-through latency (STL were determined at the end of study using passive avoidance test. Meanwhile, alternation behavior percentage was determined using Y maze. Results: There was a significant increase (p<0.05 in IL in diabetic and AG-treated diabetic groups after 4 weeks as compared to control group. In this respect, there was no significant difference between diabetic and AG-treated diabetic groups. On the other hand, STL significantly decreased (p<0.05 in diabetic group and significantly increased (p<0.05 in AG-treated diabetic group as compared to control group at the end of study. In addition, STL did not significantly change in AG-treated control group in comparison with control group. In addition, results of Y-maze test showed that there is no significant difference between diabetic and Ag-treated diabetic groups and between control and Ag-treated control group regarding alternation behavior. Discussion: In summary, chronic oral administration of AG could enhance the consolidation and recall capability of stored information only in diabetic animals and did not affect spatial memory of diabetic animals.

  14. Dosimetric Coverage of the Prostate, Normal Tissue Sparing, and Acute Toxicity with High-Dose-Rate Brachytherapy for Large Prostate Volumes

    Directory of Open Access Journals (Sweden)

    George Yang

    2015-06-01

    Full Text Available ABSTRACTPurposeTo evaluate dosimetric coverage of the prostate, normal tissue sparing, and acute toxicity with HDR brachytherapy for large prostate volumes.Materials and MethodsOne hundred and two prostate cancer patients with prostate volumes >50 mL (range: 5-29 mL were treated with high-dose-rate (HDR brachytherapy ± intensity modulated radiation therapy (IMRT to 4,500 cGy in 25 daily fractions between 2009 and 2013. HDR brachytherapy monotherapy doses consisted of two 1,350-1,400 cGy fractions separated by 2-3 weeks, and HDR brachytherapy boost doses consisted of two 950-1,150 cGy fractions separated by 4 weeks. Twelve of 32 (38% unfavorable intermediate risk, high risk, and very high risk patients received androgen deprivation therapy. Acute toxicity was graded according to the Common Terminology Criteria for Adverse Events (CTCAE version 4.ResultsMedian follow-up was 14 months. Dosimetric goals were achieved in over 90% of cases. Three of 102 (3% patients developed Grade 2 acute proctitis. No variables were significantly associated with Grade 2 acute proctitis. Seventeen of 102 (17% patients developed Grade 2 acute urinary retention. American Urological Association (AUA symptom score was the only variable significantly associated with Grade 2 acute urinary retention (p=0.04. There was no ≥ Grade 3 acute toxicity.ConclusionsDosimetric coverage of the prostate and normal tissue sparing were adequate in patients with prostate volumes >50 mL. Higher pre-treatment AUA symptom scores increased the relative risk of Grade 2 acute urinary retention. However, the overall incidence of acute toxicity was acceptable in patients with large prostate volumes.

  15. Dosimetric coverage of the prostate, normal tissue sparing, and acute toxicity with high-dose-rate brachytherapy for large prostate volumes

    Energy Technology Data Exchange (ETDEWEB)

    Yang, George; Strom, Tobin J.; Shrinath, Kushagra; Mellon, Eric A.; Fernandez, Daniel C.; Biagioli, Matthew C. [Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States); Wilder, Richard B., E-mail: mcbiagioli@yahoo.com [Cancer Treatment Centers of America, Newnan, GA (United States)

    2015-05-15

    Purpose: to evaluate dosimetric coverage of the prostate, normal tissue sparing, and acute toxicity with HDR brachytherapy for large prostate volumes. Materials and methods: one hundred and two prostate cancer patients with prostate volumes >50 mL (range: 5-29 mL) were treated with high-dose-rate (HDR) brachytherapy ± intensity modulated radiation therapy (IMRT) to 4,500 cGy in 25 daily fractions between 2009 and 2013. HDR brachytherapy monotherapy doses consisted of two 1,350-1,400 cGy fractions separated by 2-3 weeks, and HDR brachytherapy boost doses consisted of two 950-1,150 cGy fractions separated by 4 weeks. Twelve of 32 (38%) unfavorable intermediate risk, high risk, and very high risk patients received androgen deprivation therapy. Acute toxicity was graded according to the Common Terminology Criteria for Adverse Events (CTCAE) version 4. Results: median follow-up was 14 months. Dosimetric goals were achieved in over 90% of cases. Three of 102 (3%) patients developed Grade 2 acute proctitis. No variables were significantly associated with Grade 2 acute proctitis. Seventeen of 102 (17%) patients developed Grade 2 acute urinary retention. American Urological Association (AUA) symptom score was the only variable significantly associated with Grade 2 acute urinary retention (p-0.04). There was no ≥ Grade 3 acute toxicity. Conclusions: dosimetric coverage of the prostate and normal tissue sparing were adequate in patients with prostate volumes >50 mL. Higher pre-treatment AUA symptom scores increased the relative risk of Grade 2 acute urinary retention. However, the overall incidence of acute toxicity was acceptable in patients with large prostate volumes. (author)

  16. An oral TRPV1 antagonist attenuates laser radiant-heat-evoked potentials and pain ratings from UV(B)-inflamed and normal skin.

    Science.gov (United States)

    Schaffler, Klaus; Reeh, Peter; Duan, W Rachel; Best, Andrea E; Othman, Ahmed A; Faltynek, Connie R; Locke, Charles; Nothaft, Wolfram

    2013-02-01

    Laser (radiant-heat) evoked potentials (LEPs) from vertex-EEG peak-to-peak (PtP) amplitude were used to determine acute antinociceptive/antihyperalgesic efficacy of ABT-102, a novel TRPV1 antagonist efficacious in preclinical pain models, compared with active controls and placebo in normal and UV(B)-inflamed skin. This was a randomized, placebo- and active-controlled, double-blind, intra-individual, crossover trial. Twenty-four healthy subjects received six sequences of single doses of ABT-102 (0.5, 2, 6 mg), etoricoxib 90 mg, tramadol 100 mg and placebo. Painful stimuli were induced by CO(2) -laser on normal and UV(B) -inflamed skin. LEPs and visual analogue scale (VAS-pain) ratings were taken at baseline and hourly up to 8 h post-dose from both skin types. Compared with placebo, significant mean decreases in the primary variable of LEP PtP-amplitude from UV(B)-inflamed skin were observed with ABT-102 6 mg (P < 0.001), ABT-102 2 mg (P = 0.002), tramadol 100 mg (P < 0.001), and etoricoxib 90 mg (P = 0.001) over the 8 h period; ABT-102 0.5 mg was similar to placebo. ABT-102 6 mg was superior to active controls over the 8 h period (P < 0.05) whereas ABT-102 2 mg was comparable. Improvements in VAS scores compared with placebo were observed with ABT-102 6 mg (P < 0.001) and ABT-102 2 mg (P = 0.002). ABT-102 average plasma concentrations were 1.3, 4.4 and 9.4 ng ml(-1) for the 0.5, 2 and 6 mg doses, respectively. There were no clinically significant safety findings. TRPV-1 antagonism appears promising in the management of clinical pain, but requires further investigation. © 2012 Abbott. British Journal of Clinical Pharmacology © 2012 The British Pharmacological Society.

  17. Adaptive high learning rate probabilistic disruption predictors from scratch for the next generation of tokamaks

    International Nuclear Information System (INIS)

    Vega, J.; Moreno, R.; Pereira, A.; Acero, A.; Murari, A.; Dormido-Canto, S.

    2014-01-01

    The development of accurate real-time disruption predictors is a pre-requisite to any mitigation action. Present theoretical models of disruptions do not reliably cope with the disruption issues. This article deals with data-driven predictors and a review of existing machine learning techniques, from both physics and engineering points of view, is provided. All these methods need large training datasets to develop successful predictors. However, ITER or DEMO cannot wait for hundreds of disruptions to have a reliable predictor. So far, the attempts to extrapolate predictors between different tokamaks have not shown satisfactory results. In addition, it is not clear how valid this approach can be between present devices and ITER/DEMO, due to the differences in their respective scales and possibly underlying physics. Therefore, this article analyses the requirements to create adaptive predictors from scratch to learn from the data of an individual machine from the beginning of operation. A particular algorithm based on probabilistic classifiers has been developed and it has been applied to the database of the three first ITER-like wall campaigns of JET (1036 non-disruptive and 201 disruptive discharges). The predictions start from the first disruption and only 12 re-trainings have been necessary as a consequence of missing 12 disruptions only. Almost 10 000 different predictors have been developed (they differ in their features) and after the chronological analysis of the 1237 discharges, the predictors recognize 94% of all disruptions with an average warning time (AWT) of 654 ms. This percentage corresponds to the sum of tardy detections (11%), valid alarms (76%) and premature alarms (7%). The false alarm rate is 4%. If only valid alarms are considered, the AWT is 244 ms and the standard deviation is 205 ms. The average probability interval about the reliability and accuracy of all the individual predictions is 0.811 ± 0.189. (paper)

  18. Adaptive high learning rate probabilistic disruption predictors from scratch for the next generation of tokamaks

    Science.gov (United States)

    Vega, J.; Murari, A.; Dormido-Canto, S.; Moreno, R.; Pereira, A.; Acero, A.; Contributors, JET-EFDA

    2014-12-01

    The development of accurate real-time disruption predictors is a pre-requisite to any mitigation action. Present theoretical models of disruptions do not reliably cope with the disruption issues. This article deals with data-driven predictors and a review of existing machine learning techniques, from both physics and engineering points of view, is provided. All these methods need large training datasets to develop successful predictors. However, ITER or DEMO cannot wait for hundreds of disruptions to have a reliable predictor. So far, the attempts to extrapolate predictors between different tokamaks have not shown satisfactory results. In addition, it is not clear how valid this approach can be between present devices and ITER/DEMO, due to the differences in their respective scales and possibly underlying physics. Therefore, this article analyses the requirements to create adaptive predictors from scratch to learn from the data of an individual machine from the beginning of operation. A particular algorithm based on probabilistic classifiers has been developed and it has been applied to the database of the three first ITER-like wall campaigns of JET (1036 non-disruptive and 201 disruptive discharges). The predictions start from the first disruption and only 12 re-trainings have been necessary as a consequence of missing 12 disruptions only. Almost 10 000 different predictors have been developed (they differ in their features) and after the chronological analysis of the 1237 discharges, the predictors recognize 94% of all disruptions with an average warning time (AWT) of 654 ms. This percentage corresponds to the sum of tardy detections (11%), valid alarms (76%) and premature alarms (7%). The false alarm rate is 4%. If only valid alarms are considered, the AWT is 244 ms and the standard deviation is 205 ms. The average probability interval about the reliability and accuracy of all the individual predictions is 0.811 ± 0.189.

  19. Stimulus Competition in Pre/Post and Online Ratings in an Evaluative Learning Design

    Science.gov (United States)

    Purkis, Helena M.; Lipp, Ottmar V.

    2010-01-01

    Evaluative learning is said to differ from Pavlovian associative learning in that it reflects stimulus contiguity, not contingency. Thus, evaluative learning should not be subject to stimulus competition, a proposal tested in the current experiments. Participants were presented in elemental and compound training phases with pictures of shapes as…

  20. Influence of Discussion Rating in Cooperative Learning Type Numbered Head Together on Learning Results Students VII MTSN Model Padang

    Science.gov (United States)

    Sasmita, E.; Edriati, S.; Yunita, A.

    2018-04-01

    Related to the math score of the first semester in class at seventh grade of MTSN Model Padang which much the score that low (less than KKM). It because of the students who feel less involved in learning process because the teacher don't do assessment the discussions. The solution of the problem is discussion assessment in Cooperative Learning Model type Numbered Head Together. This study aims to determine whether the discussion assessment in NHT effect on student learning outcomes of class VII MTsN Model Padang. The instrument used in this study is discussion assessment and final tests. The data analysis technique used is the simple linear regression analysis. Hypothesis test results Fcount greater than the value of Ftable then the hypothesis in this study received. So it concluded that the assessment of the discussion in NHT effect on student learning outcomes of class VII MTsN Model Padang.

  1. Use of computerized tests to evaluate psychomotor performance in children with specific learning disabilities in comparison to normal children

    Directory of Open Access Journals (Sweden)

    Santosh Taur

    2014-01-01

    Full Text Available Background & objectives: Children with specific learning disabilities (SpLD have an unexplained difficulty in acquiring basic academic skills resulting in a significant discrepancy between their academic potential and achievements. This study was undertaken to compare the performance on a battery of six psychomotor tests of children with SpLD and those without any learning disabilities (controls using computerized tests. Methods: In this study, 25 children with SpLD and 25 controls (matched for age, socio-economic status and medium of instruction were given three training sessions over one week. Then children were asked to perform on the six computerized psychomotor tests. Results were compared between the two groups. Results: Children with SpLD fared significantly worse on finger tapping test, choice reaction test, digit picture substitution test and card sorting test compared to the controls ( p <0.05. Interpretation & conclusions: Children with SpLD have impairment of psychomotor skills like attention, sensory-motor coordination and executive functioning. Further research is needed to evaluate if the remedial education plan results in improvement in psychomotor performance of children with SpLD on these selected tests.

  2. Uncertainty in action-value estimation affects both action choice and learning rate of the choice behaviors of rats.

    Science.gov (United States)

    Funamizu, Akihiro; Ito, Makoto; Doya, Kenji; Kanzaki, Ryohei; Takahashi, Hirokazu

    2012-04-01

    The estimation of reward outcomes for action candidates is essential for decision making. In this study, we examined whether and how the uncertainty in reward outcome estimation affects the action choice and learning rate. We designed a choice task in which rats selected either the left-poking or right-poking hole and received a reward of a food pellet stochastically. The reward probabilities of the left and right holes were chosen from six settings (high, 100% vs. 66%; mid, 66% vs. 33%; low, 33% vs. 0% for the left vs. right holes, and the opposites) in every 20-549 trials. We used Bayesian Q-learning models to estimate the time course of the probability distribution of action values and tested if they better explain the behaviors of rats than standard Q-learning models that estimate only the mean of action values. Model comparison by cross-validation revealed that a Bayesian Q-learning model with an asymmetric update for reward and non-reward outcomes fit the choice time course of the rats best. In the action-choice equation of the Bayesian Q-learning model, the estimated coefficient for the variance of action value was positive, meaning that rats were uncertainty seeking. Further analysis of the Bayesian Q-learning model suggested that the uncertainty facilitated the effective learning rate. These results suggest that the rats consider uncertainty in action-value estimation and that they have an uncertainty-seeking action policy and uncertainty-dependent modulation of the effective learning rate. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  3. How entorhinal grid cells may learn multiple spatial scales from a dorsoventral gradient of cell response rates in a self-organizing map.

    Directory of Open Access Journals (Sweden)

    Stephen Grossberg

    Full Text Available Place cells in the hippocampus of higher mammals are critical for spatial navigation. Recent modeling clarifies how this may be achieved by how grid cells in the medial entorhinal cortex (MEC input to place cells. Grid cells exhibit hexagonal grid firing patterns across space in multiple spatial scales along the MEC dorsoventral axis. Signals from grid cells of multiple scales combine adaptively to activate place cells that represent much larger spaces than grid cells. But how do grid cells learn to fire at multiple positions that form a hexagonal grid, and with spatial scales that increase along the dorsoventral axis? In vitro recordings of medial entorhinal layer II stellate cells have revealed subthreshold membrane potential oscillations (MPOs whose temporal periods, and time constants of excitatory postsynaptic potentials (EPSPs, both increase along this axis. Slower (faster subthreshold MPOs and slower (faster EPSPs correlate with larger (smaller grid spacings and field widths. A self-organizing map neural model explains how the anatomical gradient of grid spatial scales can be learned by cells that respond more slowly along the gradient to their inputs from stripe cells of multiple scales, which perform linear velocity path integration. The model cells also exhibit MPO frequencies that covary with their response rates. The gradient in intrinsic rhythmicity is thus not compelling evidence for oscillatory interference as a mechanism of grid cell firing. A response rate gradient combined with input stripe cells that have normalized receptive fields can reproduce all known spatial and temporal properties of grid cells along the MEC dorsoventral axis. This spatial gradient mechanism is homologous to a gradient mechanism for temporal learning in the lateral entorhinal cortex and its hippocampal projections. Spatial and temporal representations may hereby arise from homologous mechanisms, thereby embodying a mechanistic "neural relativity" that

  4. Exposure to 56Fe irradiation accelerates normal brain aging and produces deficits in spatial learning and memory

    Science.gov (United States)

    Shukitt-Hale, Barbara; Casadesus, Gemma; Carey, Amanda N.; Rabin, Bernard M.; Joseph, James A.

    Previous studies have shown that radiation exposure, particularly to particles of high energy and charge (HZE particles) such as 56Fe, produces deficits in spatial learning and memory. These adverse behavioral effects are similar to those seen in aged animals. It is possible that these shared effects may be produced by the same mechanism. For example, an increased release of reactive oxygen species, and the subsequent oxidative stress and inflammatory damage caused to the central nervous system, is likely responsible for the deficits seen in aging and following irradiation. Therefore, dietary antioxidants, such as those found in fruits and vegetables, could be used as countermeasures to prevent the behavioral changes seen in these conditions. Both aged and irradiated rats display cognitive impairment in tests of spatial learning and memory such as the Morris water maze and the radial arm maze. These rats have decrements in the ability to build spatial representations of the environment, and they utilize non-spatial strategies to solve tasks. Furthermore, they show a lack of spatial preference, due to a decline in the ability to process or retain place (position of a goal with reference to a “map” provided by the configuration of numerous cues in the environment) information. These declines in spatial memory occur in measures dependent on both reference and working memory, and in the flexibility to reset mental images. These results show that irradiation with 56Fe high-energy particles produces age-like decrements in cognitive behavior that may impair the ability of astronauts, particularly middle-aged ones, to perform critical tasks during long-term space travel beyond the magnetosphere.

  5. Learning to trust: social feedback normalizes trust behavior in first-episode psychosis and clinical high risk.

    Science.gov (United States)

    Lemmers-Jansen, Imke L J; Fett, Anne-Kathrin J; Hanssen, Esther; Veltman, Dick J; Krabbendam, Lydia

    2018-06-13

    Psychosis is characterized by problems in social functioning that exist well before illness onset, and in individuals at clinical high risk (CHR) for psychosis. Trust is an essential element for social interactions that is impaired in psychosis. In the trust game, chronic patients showed reduced baseline trust, impaired response to positive social feedback, and attenuated brain activation in reward and mentalizing areas. We investigated whether first-episode psychosis patients (FEP) and CHR show similar abnormalities in the neural and behavioral mechanisms underlying trust. Twenty-two FEP, 17 CHR, and 43 healthy controls performed two trust games, with a cooperative and an unfair partner in the fMRI scanner. Region of interest analyses were performed on mentalizing and reward processing areas, during the investment and outcome phases of the games. Compared with healthy controls, FEP and CHR showed reduced baseline trust, but like controls, learned to trust in response to cooperative and unfair feedback. Symptom severity was not associated with baseline trust, however in FEP associated with reduced response to feedback. The only group differences in brain activation were that CHR recruited the temporo-parietal junction (TPJ) more than FEP and controls during investment in the unfair condition. This hyper-activation in CHR was associated with greater symptom severity. Reduced baseline trust may be associated with risk for psychotic illness, or generally with poor mental health. Feedback learning is still intact in CHR and FEP, as opposed to chronic patients. CHR however show distinct neural activation patterns of hyper-activation of the TPJ.

  6. The Self-Rating Scale of Self-Directed Learning (SRSSDL): a factor analysis of the Italian version.

    Science.gov (United States)

    Cadorin, Lucia; Bortoluzzi, Guido; Palese, Alvisa

    2013-12-01

    The development of self-directed learning (SDL) is a growing priority among nurses and other health care workers: they need to be prepared in order for their university education to be effective and relevant to their lifelong learning. To learn in a self-directed manner, it is necessary to develop an awareness of one's ability to self-learn and then to implement appropriate and effective strategies; progress must be assessed using validated measurement tools. The aim of this study was to examine the factor structure of the Italian version of the Self-Rating Scale of Self-directed Learning (SRSSDL(Ita)), and to provide evidence of its validity. A cross-sectional design was undertaken. Given that the instrument is composed of 60 items, a total of 600 to 900 participants were targeted. In addition, according to the theoretical assumption that self-directed learning - as a crucial component of lifelong learning - is a measurable skill that is developed across the individual's professional life, a maximum variation sample was examined. Therefore, 847 participants were involved, including 453 nurses, 141 radiology technicians, 182 nursing students and 68 radiology technician students. Principal component analysis and factor analysis were performed. The Italian version of the SRSSDL Scale consists of 40 items composed of eight factors: Awareness (α=0.805), Attitudes (α=0.778), Motivation (α=0.789), Learning Strategies (α=0.789), Learning Methods (α=0.781), Learning Activities (α=0.676), Interpersonal Skills (α=0.684), and Constructing Knowledge (α=0.732). The SRSSDLIta consists of 40 items across eight factors. The shorter Italian version might reduce the time needed to complete, thereby making the tool faster and easier to use. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Effect of normalization methods on the performance of supervised learning algorithms applied to HTSeq-FPKM-UQ data sets: 7SK RNA expression as a predictor of survival in patients with colon adenocarcinoma.

    Science.gov (United States)

    Shahriyari, Leili

    2017-11-03

    One of the main challenges in machine learning (ML) is choosing an appropriate normalization method. Here, we examine the effect of various normalization methods on analyzing FPKM upper quartile (FPKM-UQ) RNA sequencing data sets. We collect the HTSeq-FPKM-UQ files of patients with colon adenocarcinoma from TCGA-COAD project. We compare three most common normalization methods: scaling, standardizing using z-score and vector normalization by visualizing the normalized data set and evaluating the performance of 12 supervised learning algorithms on the normalized data set. Additionally, for each of these normalization methods, we use two different normalization strategies: normalizing samples (files) or normalizing features (genes). Regardless of normalization methods, a support vector machine (SVM) model with the radial basis function kernel had the maximum accuracy (78%) in predicting the vital status of the patients. However, the fitting time of SVM depended on the normalization methods, and it reached its minimum fitting time when files were normalized to the unit length. Furthermore, among all 12 learning algorithms and 6 different normalization techniques, the Bernoulli naive Bayes model after standardizing files had the best performance in terms of maximizing the accuracy as well as minimizing the fitting time. We also investigated the effect of dimensionality reduction methods on the performance of the supervised ML algorithms. Reducing the dimension of the data set did not increase the maximum accuracy of 78%. However, it leaded to discovery of the 7SK RNA gene expression as a predictor of survival in patients with colon adenocarcinoma with accuracy of 78%. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  8. Uncertainty in the learning rates of energy technologies. An experiment in a global multi-regional energy system model

    International Nuclear Information System (INIS)

    Rout, Ullash K.; Blesl, Markus; Fahl, Ulrich; Remme, Uwe; Voss, Alfred

    2009-01-01

    The diffusion of promising energy technologies in the market depends on their future energy production-cost development. When analyzing these technologies in an integrated assessment model using endogenous technological learning, the uncertainty in the assumed learning rates (LRs) plays a crucial role in the production-cost development and model outcomes. This study examines the uncertainty in LRs of some energy technologies under endogenous global learning implementation and presents a floor-cost modeling procedure to systematically regulate the uncertainty in LRs of energy technologies. The article narrates the difficulties of data assimilation, as compatible with mixed integer programming segmentations, and comprehensively presents the causes of uncertainty in LRs. This work is executed using a multi-regional and long-horizon energy system model based on 'TIMES' framework. All regions receive an economic advantage to learn in a common domain, and resource-ample regions obtain a marginal advantage for better exploitation of the learning technologies, due to a lower supply-side fuel-cost development. The lowest learning investment associated with the maximum LR mobilizes more deployment of the learning technologies. The uncertainty in LRs has an impact on the diffusion of energy technologies tested, and therefore this study scrutinizes the role of policy support for some of the technologies investigated. (author)

  9. Effect of vicarious fear learning on children's heart rate responses and attentional bias for novel animals.

    Science.gov (United States)

    Reynolds, Gemma; Field, Andy P; Askew, Chris

    2014-10-01

    Research with children has shown that vicarious learning can result in changes to 2 of Lang's (1968) 3 anxiety response systems: subjective report and behavioral avoidance. The current study extended this research by exploring the effect of vicarious learning on physiological responses (Lang's final response system) and attentional bias. The study used Askew and Field's (2007) vicarious learning procedure and demonstrated fear-related increases in children's cognitive, behavioral, and physiological responses. Cognitive and behavioral changes were retested 1 week and 1 month later, and remained elevated. In addition, a visual search task demonstrated that fear-related vicarious learning creates an attentional bias for novel animals, which is moderated by increases in fear beliefs during learning. The findings demonstrate that vicarious learning leads to lasting changes in all 3 of Lang's anxiety response systems and is sufficient to create attentional bias to threat in children. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  10. Effect of vicarious fear learning on children's heart rate responses and attentional bias for novel animals

    OpenAIRE

    Reynolds, G; Field, AP; Askew, C

    2014-01-01

    Research with children has shown that vicarious learning can result in changes to 2 of Lang's (1968) 3 anxiety response systems: subjective report and behavioral avoidance. The current study extended this research by exploring the effect of vicarious learning on physiological responses (Lang's final response system) and attentional bias. The study used Askew and Field's (2007) vicarious learning procedure and demonstrated fear-related increases in children's cognitive, behavioral, and physiol...

  11. Learning control for riser-slug elimination and production-rate optimization for an offshore oil and gas production process

    DEFF Research Database (Denmark)

    Pedersen, Simon; Løhndorf, Petar Durdevic; Yang, Zhenyu

    2014-01-01

    , (ii) maximizing the production rate at the riser of an offshore production platform, by manipulating a topside choke valve through a learning switching model-free PID controller. The results show good steady-state performance, though a long settling time due to the unknown reference for no slugging...

  12. Natural variation in learning and memory dynamics studied by artificial selection on learning rate in parasitic wasps

    NARCIS (Netherlands)

    Berg, van den M.; Duivenvoorde, L.; Wang, G.; Tribuhl, S.V.; Bukovinszky, T.; Vet, L.E.M.; Dicke, M.; Smid, H.M.

    2011-01-01

    Although the neural and genetic pathways underlying learning and memory formation seem strikingly similar among species of distant animal phyla, several more subtle inter- and intraspecific differences become evident from studies on model organisms. The true significance of such variation can only

  13. Clarifying Normalization

    Science.gov (United States)

    Carpenter, Donald A.

    2008-01-01

    Confusion exists among database textbooks as to the goal of normalization as well as to which normal form a designer should aspire. This article discusses such discrepancies with the intention of simplifying normalization for both teacher and student. This author's industry and classroom experiences indicate such simplification yields quicker…

  14. The Effects of Stimulus Presentation Rate on the Short-Term Memory of Learning Disabled Children.

    Science.gov (United States)

    Tarver, Sara G.; Ellsworth, Patricia S.

    To test the hypothesis that the developmental lag in verbal rehearsal which has been documented for the learning disabled is due to a naming speed deficit (i.e., slow retrieval of stimulus names), the serial recall performance of 64 learning disabled children at four grade levels (1, 3, 5, and 7) was compared under three stimulus presentation…

  15. Errors in Computing the Normalized Protein Catabolic Rate due to Use of Single-pool Urea Kinetic Modeling or to Omission of the Residual Kidney Urea Clearance.

    Science.gov (United States)

    Daugirdas, John T

    2017-07-01

    The protein catabolic rate normalized to body size (PCRn) often is computed in dialysis units to obtain information about protein ingestion. However, errors can manifest when inappropriate modeling methods are used. We used a variable volume 2-pool urea kinetic model to examine the percent errors in PCRn due to use of a 1-pool urea kinetic model or after omission of residual urea clearance (Kru). When a single-pool model was used, 2 sources of errors were identified. The first, dependent on the ratio of dialyzer urea clearance to urea distribution volume (K/V), resulted in a 7% inflation of the PCRn when K/V was in the range of 6 mL/min per L. A second, larger error appeared when Kt/V values were below 1.0 and was related to underestimation of urea distribution volume (due to overestimation of effective clearance) by the single-pool model. A previously reported prediction equation for PCRn was valid, but data suggest that it should be modified using 2-pool eKt/V and V coefficients instead of single-pool values. A third source of error, this one unrelated to use of a single-pool model, namely omission of Kru, was shown to result in an underestimation of PCRn, such that each ml/minute Kru per 35 L of V caused a 5.6% underestimate in PCRn. Marked overestimation of PCRn can result due to inappropriate use of a single-pool urea kinetic model, particularly when Kt/V <1.0 (as in short daily dialysis), or after omission of residual native kidney clearance. Copyright © 2017 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  16. Output Information Based Fault-Tolerant Iterative Learning Control for Dual-Rate Sampling Process with Disturbances and Output Delay

    Directory of Open Access Journals (Sweden)

    Hongfeng Tao

    2018-01-01

    Full Text Available For a class of single-input single-output (SISO dual-rate sampling processes with disturbances and output delay, this paper presents a robust fault-tolerant iterative learning control algorithm based on output information. Firstly, the dual-rate sampling process with output delay is transformed into discrete system in state-space model form with slow sampling rate without time delay by using lifting technology; then output information based fault-tolerant iterative learning control scheme is designed and the control process is turned into an equivalent two-dimensional (2D repetitive process. Moreover, based on the repetitive process stability theory, the sufficient conditions for the stability of system and the design method of robust controller are given in terms of linear matrix inequalities (LMIs technique. Finally, the flow control simulations of two flow tanks in series demonstrate the feasibility and effectiveness of the proposed method.

  17. Implementation of 5E Inquiry Incorporated with Analogy Learning Approach to Enhance Conceptual Understanding of Chemical Reaction Rate for Grade 11 Students

    Science.gov (United States)

    Supasorn, Saksri; Promarak, Vinich

    2015-01-01

    The main purpose of this study was to enhance student understanding of the scientific concepts of chemical reaction rate. Forty-four grade 11 students were the target group. The treatment tools were seven learning plans of 5E inquiry incorporated with an analogy learning approach during 15 hours of class time. In each learning plan, the students…

  18. Stellar reaction rate for 22Mg+p→23Al from the asymptotic normalization coefficient in the mirror nuclear system 22Ne+n→23Ne

    International Nuclear Information System (INIS)

    Al-Abdullah, T.; Carstoiu, F.; Chen, X.; Clark, H. L.; Fu, C.; Gagliardi, C. A.; Lui, Y.-W.; Mukhamedzhanov, A.; Tabacaru, G.; Tokimoto, Y.; Trache, L.; Tribble, R. E.

    2010-01-01

    The production of 22 Na in ONe novae can be influenced by the 22 Mg(p,γ) 23 Al reaction. To investigate this reaction rate at stellar energies, we have determined the asymptotic normalization coefficient (ANC) for 22 Mg+p→ 23 Al through measurements of the ANCs in the mirror nuclear system 22 Ne+n→ 23 Ne. The peripheral neutron-transfer reactions 13 C( 12 C, 13 C) 12 C and 13 C( 22 Ne, 23 Ne) 12 C were studied. The identical entrance and exit channels of the first reaction make it possible to extract independently the ground-state ANC in 13 C. Our experiment gives C p 1/2 2 ( 13 C)=2.24±0.11 fm -1 , which agrees with the value obtained from several previous measurements. The weighted average for all the obtained C p 1/2 2 is 2.31±0.08 fm -1 . This value is adopted to be used in obtaining the ANCs in 23 Ne. The differential cross sections for the reaction 13 C( 22 Ne, 23 Ne) 12 C leading to the J π =5/2 + and 1/2 + states in 23 Ne have been measured at 12 MeV/u. Optical model parameters for use in the DWBA calculations were obtained from measurements of the elastic scatterings 22 Ne+ 13 C and 22 Ne+ 12 C. The extracted ANC for the ground state in 23 Ne, C d 5/2 2 =0.86±0.08±0.12 fm -1 , is converted to its corresponding value in 23 Al using mirror symmetry to give C d 5/2 2 ( 23 Al)=(4.63±0.77)x10 3 fm -1 . The astrophysical S factor S(0) for the 22 Mg(p,γ) reaction was determined to be 0.96±0.11 keV b. The consequences for nuclear astrophysics are discussed.

  19. Evaluation of a Machine-Learning Algorithm for Treatment Planning in Prostate Low-Dose-Rate Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Nicolae, Alexandru [Department of Physics, Ryerson University, Toronto, Ontario (Canada); Department of Medical Physics, Odette Cancer Center, Sunnybrook Health Sciences Centre, Toronto, Ontario (Canada); Morton, Gerard; Chung, Hans; Loblaw, Andrew [Department of Radiation Oncology, Odette Cancer Center, Sunnybrook Health Sciences Centre, Toronto, Ontario (Canada); Jain, Suneil; Mitchell, Darren [Department of Clinical Oncology, The Northern Ireland Cancer Centre, Belfast City Hospital, Antrim, Northern Ireland (United Kingdom); Lu, Lin [Department of Radiation Therapy, Odette Cancer Center, Sunnybrook Health Sciences Centre, Toronto, Ontario (Canada); Helou, Joelle; Al-Hanaqta, Motasem [Department of Radiation Oncology, Odette Cancer Center, Sunnybrook Health Sciences Centre, Toronto, Ontario (Canada); Heath, Emily [Department of Physics, Carleton University, Ottawa, Ontario (Canada); Ravi, Ananth, E-mail: ananth.ravi@sunnybrook.ca [Department of Medical Physics, Odette Cancer Center, Sunnybrook Health Sciences Centre, Toronto, Ontario (Canada)

    2017-03-15

    Purpose: This work presents the application of a machine learning (ML) algorithm to automatically generate high-quality, prostate low-dose-rate (LDR) brachytherapy treatment plans. The ML algorithm can mimic characteristics of preoperative treatment plans deemed clinically acceptable by brachytherapists. The planning efficiency, dosimetry, and quality (as assessed by experts) of preoperative plans generated with an ML planning approach was retrospectively evaluated in this study. Methods and Materials: Preimplantation and postimplantation treatment plans were extracted from 100 high-quality LDR treatments and stored within a training database. The ML training algorithm matches similar features from a new LDR case to those within the training database to rapidly obtain an initial seed distribution; plans were then further fine-tuned using stochastic optimization. Preimplantation treatment plans generated by the ML algorithm were compared with brachytherapist (BT) treatment plans in terms of planning time (Wilcoxon rank sum, α = 0.05) and dosimetry (1-way analysis of variance, α = 0.05). Qualitative preimplantation plan quality was evaluated by expert LDR radiation oncologists using a Likert scale questionnaire. Results: The average planning time for the ML approach was 0.84 ± 0.57 minutes, compared with 17.88 ± 8.76 minutes for the expert planner (P=.020). Preimplantation plans were dosimetrically equivalent to the BT plans; the average prostate V150% was 4% lower for ML plans (P=.002), although the difference was not clinically significant. Respondents ranked the ML-generated plans as equivalent to expert BT treatment plans in terms of target coverage, normal tissue avoidance, implant confidence, and the need for plan modifications. Respondents had difficulty differentiating between plans generated by a human or those generated by the ML algorithm. Conclusions: Prostate LDR preimplantation treatment plans that have equivalent quality to plans created

  20. Evaluation of a Machine-Learning Algorithm for Treatment Planning in Prostate Low-Dose-Rate Brachytherapy

    International Nuclear Information System (INIS)

    Nicolae, Alexandru; Morton, Gerard; Chung, Hans; Loblaw, Andrew; Jain, Suneil; Mitchell, Darren; Lu, Lin; Helou, Joelle; Al-Hanaqta, Motasem; Heath, Emily; Ravi, Ananth

    2017-01-01

    Purpose: This work presents the application of a machine learning (ML) algorithm to automatically generate high-quality, prostate low-dose-rate (LDR) brachytherapy treatment plans. The ML algorithm can mimic characteristics of preoperative treatment plans deemed clinically acceptable by brachytherapists. The planning efficiency, dosimetry, and quality (as assessed by experts) of preoperative plans generated with an ML planning approach was retrospectively evaluated in this study. Methods and Materials: Preimplantation and postimplantation treatment plans were extracted from 100 high-quality LDR treatments and stored within a training database. The ML training algorithm matches similar features from a new LDR case to those within the training database to rapidly obtain an initial seed distribution; plans were then further fine-tuned using stochastic optimization. Preimplantation treatment plans generated by the ML algorithm were compared with brachytherapist (BT) treatment plans in terms of planning time (Wilcoxon rank sum, α = 0.05) and dosimetry (1-way analysis of variance, α = 0.05). Qualitative preimplantation plan quality was evaluated by expert LDR radiation oncologists using a Likert scale questionnaire. Results: The average planning time for the ML approach was 0.84 ± 0.57 minutes, compared with 17.88 ± 8.76 minutes for the expert planner (P=.020). Preimplantation plans were dosimetrically equivalent to the BT plans; the average prostate V150% was 4% lower for ML plans (P=.002), although the difference was not clinically significant. Respondents ranked the ML-generated plans as equivalent to expert BT treatment plans in terms of target coverage, normal tissue avoidance, implant confidence, and the need for plan modifications. Respondents had difficulty differentiating between plans generated by a human or those generated by the ML algorithm. Conclusions: Prostate LDR preimplantation treatment plans that have equivalent quality to plans created

  1. On the electrification of road transport - Learning rates and price forecasts for hybrid-electric and battery-electric vehicles

    International Nuclear Information System (INIS)

    Weiss, Martin; Patel, Martin K.; Junginger, Martin; Perujo, Adolfo; Bonnel, Pierre; Grootveld, Geert van

    2012-01-01

    Hybrid-electric vehicles (HEVs) and battery-electric vehicles (BEVs) are currently more expensive than conventional passenger cars but may become cheaper due to technological learning. Here, we obtain insight into the prospects of future price decline by establishing ex-post learning rates for HEVs and ex-ante price forecasts for HEVs and BEVs. Since 1997, HEVs have shown a robust decline in their price and price differential at learning rates of 7±2% and 23±5%, respectively. By 2010, HEVs were only 31±22 € 2010 kW −1 more expensive than conventional cars. Mass-produced BEVs are currently introduced into the market at prices of 479±171 € 2010 kW −1 , which is 285±213 € 2010 kW −1 and 316±209 € 2010 kW −1 more expensive than HEVs and conventional cars. Our forecast suggests that price breakeven with these vehicles may only be achieved by 2026 and 2032, when 50 and 80 million BEVs, respectively, would have been produced worldwide. We estimate that BEVs may require until then global learning investments of 100–150 billion € which is less than the global subsidies for fossil fuel consumption paid in 2009. These findings suggest that HEVs, including plug-in HEVs, could become the dominant vehicle technology in the next two decades, while BEVs may require long-term policy support. - Highlights: ► Learning rates for hybrid-electric and battery-electric vehicles. ► Prices and price differentials of hybrid-electric vehicles show a robust decline. ► Battery-electric vehicles may require policy support for decades.

  2. Prediction and early detection of delirium in the intensive care unit by using heart rate variability and machine learning.

    Science.gov (United States)

    Oh, Jooyoung; Cho, Dongrae; Park, Jaesub; Na, Se Hee; Kim, Jongin; Heo, Jaeseok; Shin, Cheung Soo; Kim, Jae-Jin; Park, Jin Young; Lee, Boreom

    2018-03-27

    Delirium is an important syndrome found in patients in the intensive care unit (ICU), however, it is usually under-recognized during treatment. This study was performed to investigate whether delirious patients can be successfully distinguished from non-delirious patients by using heart rate variability (HRV) and machine learning. Electrocardiography data of 140 patients was acquired during daily ICU care, and HRV data were analyzed. Delirium, including its type, severity, and etiologies, was evaluated daily by trained psychiatrists. HRV data and various machine learning algorithms including linear support vector machine (SVM), SVM with radial basis function (RBF) kernels, linear extreme learning machine (ELM), ELM with RBF kernels, linear discriminant analysis, and quadratic discriminant analysis were utilized to distinguish delirium patients from non-delirium patients. HRV data of 4797 ECGs were included, and 39 patients had delirium at least once during their ICU stay. The maximum classification accuracy was acquired using SVM with RBF kernels. Our prediction method based on HRV with machine learning was comparable to previous delirium prediction models using massive amounts of clinical information. Our results show that autonomic alterations could be a significant feature of patients with delirium in the ICU, suggesting the potential for the automatic prediction and early detection of delirium based on HRV with machine learning.

  3. Birkhoff normalization

    NARCIS (Netherlands)

    Broer, H.; Hoveijn, I.; Lunter, G.; Vegter, G.

    2003-01-01

    The Birkhoff normal form procedure is a widely used tool for approximating a Hamiltonian systems by a simpler one. This chapter starts out with an introduction to Hamiltonian mechanics, followed by an explanation of the Birkhoff normal form procedure. Finally we discuss several algorithms for

  4. The influence of surgical transection and anastomosis on the rate of cell proliferation in the colonic epithelium of normal and DMH-treated rats.

    Science.gov (United States)

    Barkla, D H; Tutton, P M

    1983-10-01

    Normal and DMH-treated male rats aged 18-20 weeks underwent surgical transection and anastomosis of the transverse colon. Animals were subsequently killed at intervals of 14, 30 and 72 days. Three hours prior to sacrifice animals were injected with vinblastine sulphate and mitotic indices were subsequently estimated in histological sections. Possible differences between experimental and control groups were tested using a Student's t-test. The results show that the accumulated mitotic indices in normal and DMH-treated colon are statistically similar. The results also show that transection and anastomosis stimulates cell division in both normal and DMH-treated colon and that the increase is of greater amplitude and more prolonged duration in the DMH-treated rats. Carcinomas developed close to the line of anastomosis in DMH-treated but not in control rats. The results support the hypothesis that non-specific injury to hyperplastic colonic epithelium promotes carcinogenesis.

  5. Retrospective analysis of the learning curve associated with laparoscopic ovariectomy in dogs and associated perioperative complication rates.

    Science.gov (United States)

    Pope, Juliet Frances Anne; Knowles, Toby Grahame

    2014-08-01

    To assess the learning curve associated with laparoscopic ovariectomy (LOE) in 618 dogs and to report perioperative complication rates. Case series. Dogs (n = 618). Data retrieved from the medical records of bitches admitted for LOE over 42 months included date of surgery, breed, weight (kg), age (months), surgeon, suture material used, intraoperative complications and postoperative complications. Each LOE was defined as "successful" or "unsuccessful" by the absence or presence of an intraoperative complication and "failure" rate described using a CUSUM technique. Follow-up time ranged from 152 to 1,435 days (median, 737 days). Intraoperative complications occurred in 10 dogs (1.6%) and included: splenic laceration (6 dogs; 1%), urinary bladder perforation (3 dogs; 0.5%), and subcutaneous emphysema (1 dog; 0.2%). Postoperative complications occurred in 99 dogs (16%) and included: incisional inflammation treated with antibiotics (87 dogs [14%]; 96/1,854 incisions; 5.1%), incisional seroma (5 dogs [0.8%]; 5/1,854 incisions, 0.3%), incisional hernia (4 dogs [0.6%]; 4/1,854 incisions, 0.2%), and ovarian remnant syndrome (3 dogs; 0.5%). CUSUM charts indicated an initial "learning curve" of ∼80 LOE. LOE is a technique with an initial learning curve but once surgical proficiency is reached after ∼80 procedures then intraoperative complication rates associated with the procedure can be low. © Copyright 2014 by The American College of Veterinary Surgeons.

  6. High Classification Rates for Continuous Cow Activity Recognition using Low-cost GPS Positioning Sensors and Standard Machine Learning Techniques

    DEFF Research Database (Denmark)

    Godsk, Torben; Kjærgaard, Mikkel Baun

    2011-01-01

    activities. By preprocessing the raw cow position data, we obtain high classification rates using standard machine learning techniques to recognize cow activities. Our objectives were to (i) determine to what degree it is possible to robustly recognize cow activities from GPS positioning data, using low...... and their activities manually logged to serve as ground truth. For our dataset we managed to obtain an average classification success rate of 86.2% of the four activities: eating/seeking (90.0%), walking (100%), lying (76.5%), and standing (75.8%) by optimizing both the preprocessing of the raw GPS data...

  7. Behavioral Repertoire Influences the Rate and Nature of Learning in Climbing: Implications for Individualized Learning Design in Preparation for Extreme Sports Participation

    Directory of Open Access Journals (Sweden)

    Dominic Orth

    2018-06-01

    Full Text Available Extreme climbing where participants perform while knowing that a simple mistake could result in death requires a skill set normally acquired in non-extreme environments. In the ecological dynamics approach to perception and action, skill acquisition involves a process where the existing repertoire of behavioral capabilities (or coordination repertoire of a learner are destabilized and re-organized through practice—this process can expand the individuals affordance boundaries allowing the individual to explore new environments. Change in coordination repertoire has been observed in bi-manual coordination and postural regulation tasks, where individuals begin practice using one mode of coordination before transitioning to another, more effective, coordination mode during practice. However, individuals may also improve through practice without qualitatively reorganizing movement system components—they do not find a new mode of coordination. To explain these individual differences during learning (i.e., whether or not a new action is discovered, a key candidate is the existing coordination repertoire present prior to practice. In this study, the learning dynamics of body configuration patterns organized with respect to an indoor climbing surface were observed and the existing repertoire of coordination evaluated prior to and after practice. Specifically, performance outcomes and movement patterns of eight beginners were observed across 42 trials of practice over a 7-week period. A pre- and post-test scanning procedure was used to determine existing patterns of movement coordination and the emergence of new movement patterns after the practice period. Data suggested the presence of different learning dynamics by examining trial-to-trial performance in terms of jerk (an indicator of climbing fluency, at the individual level of analysis. The different learning dynamics (identified qualitatively included: continuous improvement, sudden improvement

  8. Perception of a Sung Vowel as a Function of Frequency-Modulation Rate and Excursion in Listeners with Normal Hearing and Hearing Impairment

    Science.gov (United States)

    Vatti, Marianna; Santurette, Sébastien; Pontoppidan, Niels Henrik; Dau, Torsten

    2014-01-01

    Purpose: Frequency fluctuations in human voices can usually be described as coherent frequency modulation (FM). As listeners with hearing impairment (HI listeners) are typically less sensitive to FM than listeners with normal hearing (NH listeners), this study investigated whether hearing loss affects the perception of a sung vowel based on FM…

  9. Apolipoprotein E Genotype and educational attainment predict the rate of cognitive decline in normal aging? A 12-year follow-up of the Maastricht Aging Study

    NARCIS (Netherlands)

    van Gerven, P.W.; van Boxtel, M.P.J.; Bekers, O.; Ausems, E.E.B.; Jolles, J.

    2012-01-01

    Objective: We investigated suspected longitudinal interaction effects of apolipoprotein E (APOE) genotype and educational attainment on cognitive decline in normal aging. Method: Our sample consisted of 571 healthy, nondemented adults aged between 49 and 82 years. Linear mixed-models analyses were

  10. Colour in Learning: Its Effect on the Retention Rate of Graduate Students

    Science.gov (United States)

    Olurinola, Oluwakemi; Tayo, Omoniyi

    2015-01-01

    Cognitive psychologists have discovered different design principles to enhance memory performance. It has been said that retrieving process depends on many variables and one of them is colour. This paper provides an overview of research on colour and learning. It includes the effect of colour on attention, retention and memory performance, and…

  11. MO-DE-207A-09: Low-Dose CT Image Reconstruction Via Learning From Different Patient Normal-Dose Images

    Energy Technology Data Exchange (ETDEWEB)

    Han, H; Xing, L [Stanford University, Palo Alto, CA (United States); Liang, Z [Stony Brook University, Stony Brook, NY (United States)

    2016-06-15

    Purpose: To investigate a novel low-dose CT (LdCT) image reconstruction strategy for lung CT imaging in radiation therapy. Methods: The proposed approach consists of four steps: (1) use the traditional filtered back-projection (FBP) method to reconstruct the LdCT image; (2) calculate structure similarity (SSIM) index between the FBP-reconstructed LdCT image and a set of normal-dose CT (NdCT) images, and select the NdCT image with the highest SSIM as the learning source; (3) segment the NdCT source image into lung and outside tissue regions via simple thresholding, and adopt multiple linear regression to learn high-order Markov random field (MRF) pattern for each tissue region in the NdCT source image; (4) segment the FBP-reconstructed LdCT image into lung and outside regions as well, and apply the learnt MRF prior in each tissue region for statistical iterative reconstruction of the LdCT image following the penalized weighted least squares (PWLS) framework. Quantitative evaluation of the reconstructed images was based on the signal-to-noise ratio (SNR), local binary pattern (LBP) and histogram of oriented gradients (HOG) metrics. Results: It was observed that lung and outside tissue regions have different MRF patterns predicted from the NdCT. Visual inspection showed that our method obviously outperformed the traditional FBP method. Comparing with the region-smoothing PWLS method, our method has, in average, 13% increase in SNR, 15% decrease in LBP difference, and 12% decrease in HOG difference from reference standard for all regions of interest, which indicated the superior performance of the proposed method in terms of image resolution and texture preservation. Conclusion: We proposed a novel LdCT image reconstruction method by learning similar image characteristics from a set of NdCT images, and the to-be-learnt NdCT image does not need to be scans from the same subject. This approach is particularly important for enhancing image quality in radiation therapy.

  12. MO-DE-207A-09: Low-Dose CT Image Reconstruction Via Learning From Different Patient Normal-Dose Images

    International Nuclear Information System (INIS)

    Han, H; Xing, L; Liang, Z

    2016-01-01

    Purpose: To investigate a novel low-dose CT (LdCT) image reconstruction strategy for lung CT imaging in radiation therapy. Methods: The proposed approach consists of four steps: (1) use the traditional filtered back-projection (FBP) method to reconstruct the LdCT image; (2) calculate structure similarity (SSIM) index between the FBP-reconstructed LdCT image and a set of normal-dose CT (NdCT) images, and select the NdCT image with the highest SSIM as the learning source; (3) segment the NdCT source image into lung and outside tissue regions via simple thresholding, and adopt multiple linear regression to learn high-order Markov random field (MRF) pattern for each tissue region in the NdCT source image; (4) segment the FBP-reconstructed LdCT image into lung and outside regions as well, and apply the learnt MRF prior in each tissue region for statistical iterative reconstruction of the LdCT image following the penalized weighted least squares (PWLS) framework. Quantitative evaluation of the reconstructed images was based on the signal-to-noise ratio (SNR), local binary pattern (LBP) and histogram of oriented gradients (HOG) metrics. Results: It was observed that lung and outside tissue regions have different MRF patterns predicted from the NdCT. Visual inspection showed that our method obviously outperformed the traditional FBP method. Comparing with the region-smoothing PWLS method, our method has, in average, 13% increase in SNR, 15% decrease in LBP difference, and 12% decrease in HOG difference from reference standard for all regions of interest, which indicated the superior performance of the proposed method in terms of image resolution and texture preservation. Conclusion: We proposed a novel LdCT image reconstruction method by learning similar image characteristics from a set of NdCT images, and the to-be-learnt NdCT image does not need to be scans from the same subject. This approach is particularly important for enhancing image quality in radiation therapy.

  13. The Reliability and Validity of the English and Spanish Strengths and Weaknesses of ADHD and Normal Behavior Rating Scales in a Preschool Sample: Continuum Measures of Hyperactivity and Inattention

    Science.gov (United States)

    Lakes, Kimberley D.; Swanson, James M.; Riggs, Matt

    2012-01-01

    Objective: To evaluate the reliability and validity of the English and Spanish versions of the Strengths and Weaknesses of ADHD-symptom and Normal-behavior (SWAN) rating scale. Method: Parents of preschoolers completed both a SWAN and the well-established Strengths and Difficulties Questionnaire (SDQ) on two separate occasions over a span of 3…

  14. Implementasi Jaringan Syaraf Tiruan Recurrent Menggunakan Gradient Descent Adaptive Learning Rate and Momentum Untuk Pendugaan Curah Hujan

    Directory of Open Access Journals (Sweden)

    Afan Galih Salman

    2011-06-01

    Full Text Available The artificial neural network (ANN technology in rainfall prediction can be done using the learning approach. The ANN prediction accuracy is measured by the determination coefficient (R2 and root mean square error (RMSE. This research implements Elman’s Recurrent ANN which is heuristically optimized based on el-nino southern oscilation (ENSO variables: wind, southern oscillation index (SOI, sea surface temperatur (SST dan outgoing long wave radiation (OLR to forecast regional monthly rainfall in Bongan Bali. The heuristic learning optimization done is basically a performance development of standard gradient descent learning algorithm into training algorithms: gradient descent momentum and adaptive learning rate. The patterns of input data affect the performance of Recurrent Elman neural network in estimation process. The first data group that is 75% training data and 25% testing data produce the maximum R2 leap 74,6% while the second data group that is 50% training data and 50% testing data produce the maximum R2 leap 49,8%.

  15. Investigating the Effectiveness of Case-based Learning Instruction on Students’ Understanding the Subject of Reaction Rate

    Directory of Open Access Journals (Sweden)

    Aysel Ünal SÜMEN

    2015-04-01

    Full Text Available This study has been carried out to determine the effectiveness of case-based learning related to reaction rate on students’ conceptual understanding and conceptual change. In this respect, a class of 11th grade students in an Anatolian High School in the center of Izmir city was chosen randomly as experimental group (n=26 and another as control group (n=22. Reaction rate unit was taught to the experimental group within case-based learning method, and to the control group through activities defined in Chemistry curriculum. Comprehension Test developed by Cakmakci (2005 was utilized as data collecting instrument. The Comprehension Test was applied simultaneously to both experimental and control groups before and after the teaching. The data collected via the Comprehension Test was analyzed in terms of both quantity and quality. As a result of the study, it was noted that there was a significant difference between the groups after the instruction in favor of the experimental group. Also, it was determined that case-based learning was more effective in promoting conceptual change and assuring higher level of conceptual understanding for students.

  16. Event-related brain potentials, bilateral electrodermal activity and Mangina-Test performance in learning disabled/ADHD pre-adolescents with severe behavioral disorders as compared to age-matched normal controls.

    Science.gov (United States)

    Mangina, C A; Beuzeron-Mangina, J H; Grizenko, N

    2000-07-01

    The most frequently encountered developmental problems of learning disabilities/ADHD often co-exist with severe behavioral disorders. As a direct consequence, this condition opens the way to delinquency, school drop-out, depression, suicide, substance abuse, work absenteeism, and other psycho-social complications. In this paper, we are presenting a selective overview of our previous research and its clinical applications in this field as it relates to our present research data pertaining to the effects of our original Memory Workload Paradigm on the event-related brain potentials in differentiating normal and pathological pre-adolescents (learning disabled/ADHD with concomitant severe behavioral disorders such as oppositional and conduct). In addition, it provides data on the bilateral electrodermal activity during cognitive workload and Mangina-Test performance of pathological and normal pre-adolescents conducted in separate sessions. The results of our present research indicate that a significant memory load effect for the P450 latency (F(3,27)=4.98, PWorkload Paradigm in pre-frontal and frontal regions clearly differentiated normal from pathological pre-adolescents (F(1, 18)=12.21, Presearch findings provide an original and valuable demonstration of an integrative and effective clinical psychophysiological application of central (ERPs), autonomic (bilateral electrodermal activity) and neuro-psychometric aspects (Mangina-Test) which characterize normal and pathological pre-adolescents and underpin the neurophysiological basis of learning disabled/ADHD with severe behavioral disorders as opposed to normal subjects.

  17. Effects of low dose rate γ-rays on cell proliferation and survival in exponentially growing and plateau phase cultures of normal rat kidney cells

    International Nuclear Information System (INIS)

    Tsuboi, A.

    1982-01-01

    The effects of 60 Co γ-rays on cell clonogenicity and cell proliferation were examined in NRK cells in exponential and plateau growth phases during and after irradiation at various dose rates. The typical dese rate effect for the survival responses was observed between acute irradiation and continuous irradiation at dose rates of 9.6-44 rads/h. Similar dose rate effect for the perturbation of the proliferation was observed in exponentially growing cells during irradiation. Some differences were found in survival when the cells were exposed to γ-rays at 9.6 rads/h or at 13.7 rads/h. The survival curves of exponential phase cells irradiated at these dose rates showed a shape different from that observed in plateau phase cells. Namely, a steady state of survival appeared around an accumulated dose of 1000 rads (dose-rate of 9.6 rads/h) and an accumulated dose of 1500 rads (dose-rate of 13.7 rads/h) in the exponential phase cells, while such a steady state of survival was not detected in plateau phase cells after similar conditions of irradiation. Moreover, the extrapolation number of the survival curve was much larger at the lower dose rate in exponential phase cells, in contrast to a value of the unity oberved in plateau phase cells, The radiosensitivity of plateau phase cells was somewhat lower compared to exponential phase cells over the range of accumulated doses at the dose rates used. These differences in cellular responses to the radiation between the two phases could be explained by changes in cell proliferation, the redistribution of the cell cycle compartments and the repair capacity of cellular damage during irradiation. (author)

  18. Learning by Heart: Students Use Heart Rate Patterns To Identify Nervous System Imbalances.

    Science.gov (United States)

    Ackerly, Spafford C.

    2001-01-01

    Introduces a science unit on heart rate variability (HVR) patterns. Uses spectral analysis to determine the effects of environmental stimulants such as music and emotional stress on heart rate. Observes relaxation techniques and their effects on the autonomous nervous system. (Contains 12 references.) (YDS)

  19. Insulin's acute effects on glomerular filtration rate correlate with insulin sensitivity whereas insulin's acute effects on proximal tubular sodium reabsorption correlate with salt sensitivity in normal subjects

    NARCIS (Netherlands)

    ter Maaten, JC; Bakker, SJL; Serne, EH; ter Wee, PM; Gans, ROB

    1999-01-01

    Background. Insulin induces increasing distal tubular sodium reabsorption. Opposite effects of insulin to offset insulin-induced sodium retention are supposedly increases in glomerular filtration rate (GFR) and decreases in proximal tubular sodium reabsorption. Defects in these opposing effects

  20. SEP PREPÁRATE: modelos de educación a distancia en el nivel medio superior SEP PREPÁRATE: e-learning models for high school

    Directory of Open Access Journals (Sweden)

    Gomez Zermeño Marcela Georgina

    2011-07-01

    Full Text Available Este documento presenta un estudio realizado sobre modelos innovadores de educación a distancia para adolescentes, con el propósito de generar información sobre los factores que permiten lograr que alumnos inscritos en programas a distancia, desarrollen las habilidades necesarias para su aprendizaje. Los alumnos que conforman la muestra de estudio, son adolescentes entre los 15 y 17 años de edad, en condiciones de rezago económico pero con necesidades propias de su edad y deseos de obtener sus estudios de preparatoria, inscritos en la Universidad TecMilenio y apoyados por la Fundación Bécalos, para que participen en el programa SEP Prepárate. Los alumnos cuentan con las herramientas necesarias para lograr sus estudios como son beca escolar, apoyo económico durante sus estudios, equipo de cómputo, conexión a Internet y Modem. Durante los trabajos de campo, se realizaron encuestas a los alumnos y padres de familia, entrevistas personales a los alumnos exitosos y a los alumnos no exitosos. El análisis de la información reveló que el programa SEP Prepárate creado por la Secretaría de Educación Pública y la Universidad Tecmilenio, es una alternativa viable que atiende las necesidades propias de los alumnos que estudian a distancia y como ayudar a los estudiantes a llegar con éxito al final de sus estudios de preparatoria. This document presents a study done about innovative e-learning models for trailed adolescents; it seeks to generate relevant information about the elements that would guarantee that enrolled students into an e-learning program develop the needed abilities for their instruction. The sample students that took part are adolescents between 15 and 17 years old, in poverty conditions but with the desire to graduate high school as any other teenager. The students are enrolled at TecMilenio University with the financial support of Fundación Bécalos, in coordination with the Mexican Ministry of Public Education, within

  1. Salivary protein concentration, flow rate, buffer capacity and pH estimation: A comparative study among young and elderly subjects, both normal and with gingivitis and periodontitis.

    Science.gov (United States)

    Shaila, Mulki; Pai, G Prakash; Shetty, Pushparaj

    2013-01-01

    To evaluate the salivary protein concentration in gingivitis and periodontitis patients and compare the parameters like salivary total protein, salivary albumin, salivary flow rate, pH, buffer capacity and flow rate in both young and elderly patients with simple methods. One hundred and twenty subjects were grouped based on their age as young and elderly. Each group was subgrouped (20 subjects) as controls, gingivitis and periodontitis. Unstimulated whole saliva was collected from patients and flow rate was noted down during collection of the sample. Salivary protein estimation was done using the Biuret method and salivary albumin was assessed using the Bromocresol green method. pH was estimated with a pHmeter and buffering capacity was analyzed with the titration method. Student's t-test, Fisher's test (ANOVA) and Tukey HSD (ANOVA) tests were used for statistical analysis. A very highly significant rise in the salivary total protein and albumin concentration was noted in gingivitis and periodontitis subjects of both young and elderly. An overall decrease in salivary flow rate was observed among the elderly, and also the salivary flow rate of women was significantly lower than that of men. Significant associations between salivary total protein and albumin in gingivitis and periodontitis were found with simple biochemical tests. A decrease in salivary flow rate among elderly and among women was noted.

  2. A Study of Course Design Factors that Influence E-Learning Course Completion Rates

    National Research Council Canada - National Science Library

    Mathews, Edward

    2004-01-01

    .... Although there is significant variation among institutions - with some reporting course-completion rates of more than 80 percent and others finding that fewer than 50 percent of distance-education...

  3. A twin study of Attention-Deficit/Hyperactivity Disorder Dimensions rated by the Strengths and Weaknesses of ADHD-symptoms and Normal-behavior (SWAN) Scale

    NARCIS (Netherlands)

    Hay, D.A.; Bennett, K.S.; Levy, J.; Sergeant, J.A.; Swanson, J.

    2007-01-01

    Background: When symptom rating scales are used in the general population, there is severe skewness, with many individuals having no symptoms. While this has major implications for genetic designs that require extremely discordant and concordant (EDAC) siblings, little is known of the genetics of

  4. The effect of study time distribution on learning and retention: a Goldilocks principle for presentation rate.

    Science.gov (United States)

    de Jonge, Mario; Tabbers, Huib K; Pecher, Diane; Zeelenberg, René

    2012-03-01

    In 2 experiments, we investigated the effect of presentation rate on both immediate (5 min) and delayed (2 days) cued recall of paired associates. Word pairs were presented for a total of 16 s per pair, with presentation duration of individual presentations varying from 1 to 16 s. In Experiment 1, participants studied word pairs with presentation rates of 16 × 1 s, 8 × 2 s, 4 × 4 s, 2 × 8 s, or 1 × 16 s. A nonmonotonic relationship was found between presentation rate and cued recall performance. Both short (e.g., 1 s) and long (e.g., 16 s) presentation durations resulted in poor immediate and delayed recall, compared with intermediate presentation durations. In Experiment 2, we replicated these general findings. Moreover, we showed that the 4 s condition resulted in less proportional forgetting than the 1 s and the 16 s conditions. 2012 APA, all rights reserved

  5. The Blood Disappearance Rate of 1{sup 98A}u-Colloid and Changes of Hepatic Blood Flow During Position Change in Normal Persons and in Patients with Various Hepatic Diseases

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Bo Yeon [Capital Armed Force General Hospital, Seoul (Korea, Republic of); Hong, Kee Suk; Koh, Chang Soon; Lee, Mun Ho [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1977-03-15

    To evaluate the diagnostic significance of the blood disappearance rate of {sup 198}Au-colloid and to evaluate the change of hepatic blood flow during position change from supine to erect, we measured the half time of blood disappearance rate of {sup 198}Au-colloid using external counting method in 94 normal persons and in 77 patients with various hepatic diseases. The results obtained were as follows: 1) In normal control, the mean blood disappearance half time of {sup 198}Au-colloid in supine position was 2.7+-0.4 minutes. There was no significant difference of hepatic blood flow in age and sex. 2) In acute hepatitis, chronic hepatitis and hepatic cirrhosis, the mean blood disappearance half times in supine position were 3.0+-0.45, 3.5+-0.74, 7.2+-3.6 minutes respectively. The hepatic blood flow of the patients with chronic hepatitis and hepatic cirrhosis were significantly decreased than that of normal control. 3) In the normal control and acute hepatitis, the decreases of the hepatic blood flow during the position change from supine to erect were 27.7% and 22.6% respectively.

  6. Malware Normalization

    OpenAIRE

    Christodorescu, Mihai; Kinder, Johannes; Jha, Somesh; Katzenbeisser, Stefan; Veith, Helmut

    2005-01-01

    Malware is code designed for a malicious purpose, such as obtaining root privilege on a host. A malware detector identifies malware and thus prevents it from adversely affecting a host. In order to evade detection by malware detectors, malware writers use various obfuscation techniques to transform their malware. There is strong evidence that commercial malware detectors are susceptible to these evasion tactics. In this paper, we describe the design and implementation of a malware normalizer ...

  7. Reducing the drop-out rate of a technical oriented course by introducing Problem Based Learning – a first concept

    Directory of Open Access Journals (Sweden)

    Christian Kaufmann

    2011-04-01

    Full Text Available At the University of Applied Sciences (UAS Technikum Wien one of the most difficult courses in the Bachelor degree program of Computer Science is “Database Systems and Database Design”. Together with “Advanced Computer Programming”, this course accounts for the high drop-out rate in the degree program. For this reason, this course was chosen for a redesign, in line with the research project QUADRO (Measures to increase quality of teaching and to reduce drop-out rates promoted by the City of Vienna – MA 27 (EU strategy and promote economic development. As the authors have already gained experience in Problem Based Learning (PBL, they saw an opportunity to improve students’ database knowledge by changing the teaching method to Problem Based Learning (PBL. The proposed paper first explains the current situation, identifies its drawbacks and difficulties. In a second step, it describes the new method, shows the students’ feedback after the first semester and the resulting changes in the concept.

  8. Comparison of the Readiness for Interprofessional Learning and the rate of contact among students from nine different healthcare courses.

    Science.gov (United States)

    de Oliveira, Vítor Falcão; Bittencourt, Mariana Fonseca; Navarro Pinto, Ícaro França; Lucchetti, Alessandra Lamas Granero; da Silva Ezequiel, Oscarina; Lucchetti, Giancarlo

    2018-04-01

    Despite the growth in the interprofessional literature, there are still few studies that have evaluated the differences among courses and periods in relation to Readiness for Interprofessional Learning. Likewise, the relationship between the influences of contact among students from different professions is still controversial. To evaluate whether greater contact among students from diverse health courses could be associated with improved Readiness for Interprofessional Learning (RIPLS) at the undergraduate level and to compare the RIPLS among healthcare courses, analyzing differences among courses and periods of their academic training. Cross-sectional study. A Brazilian public university. Students enrolled in the first and final periods of nine healthcare courses. The rates of contact between students and the Readiness for Interprofessional Learning were assessed. A comparison between students from these nine healthcare courses was carried out. A total of 545 (73.45%) students answered the questionnaire. The highest RIPLS scores were from Nursing (42.39), Dentistry (41.33) and Pharmacy students (40.72) and the lowest scores were from Physical Education (38.02), Medicine (38.17) and Psychology (38.66) students. The highest rates of contact between students (RC) were from Physical Education, Nutrition and Psychology students and the lowest RC were from Pharmacy, Social service and Dentistry. There was a significant effect of "healthcare course" on RIPLS. Comparing RIPLS and RC between the first and final years we found that, considering all courses, there was an increase in the RC, whereas a decrease in RIPLS scores. No correlation was found between RIPLS and RC in general. The current study found that RIPLS scores are very different between healthcare students. Although we found a significant increase in the RC, there was a decrease in the RIPLS scores. These findings lead to a greater understanding of the difficulties facing and potential for interprofessional

  9. Artificial neural networks can learn to estimate extinction rates from molecular phylogenies

    NARCIS (Netherlands)

    Bokma, Folmer

    2006-01-01

    Molecular phylogenies typically consist of only extant species, yet they allow inference of past rates of extinction, because. recently originated species are less likely to be extinct than ancient species. Despite the simple structure of the assumed underlying speciation-extinction process,

  10. Reducing Student "Suspension Rates" and Engaging Students in Learning: Principal and Teacher Approaches that Work

    Science.gov (United States)

    Riordan, Geoff

    2006-01-01

    The negative effects of student suspension from school on both the individual and the community are well documented and relate to a wide range of matters, including school completion rates, homelessness and crime. Two recent, extensive reviews of student suspensions in government and non-government schools in N.S.W. (Gonczi and Riordan, 2002;…

  11. Fisetin-Rich Extracts of Rhus verniciflua Stokes Improve Blood Flow Rates in Mice Fed Both Normal and High-Fat Diets.

    Science.gov (United States)

    Im, Won Kyun; Park, Hyun Jung; Lee, Kwang Soo; Lee, Jung Hoon; Kim, Young Dong; Kim, Kyeong-Hee; Park, Sang-Jae; Hong, Seokmann; Jeon, Sung Ho

    2016-02-01

    Although it has been previously reported that Rhus verniciflua Stokes (RVS) possesses in vitro anti-inflammatory activity, the precise in vivo mechanisms of RVS extracts and a main active component called fisetin have not been well elucidated. In this study, using newly developed protocols, we prepared urushiol-free but fisetin-enriched RVS extracts and investigated their effects on the vascular immune system. We found that the water-soluble fractions of detoxified RVS with the flavonoid fisetin can inhibit lipopolysaccharide-induced production of nitric oxide (NO) and prostaglandin E2 (PGE2). Furthermore, RVS can reduce inducible nitric oxide synthase and COX2 gene expression levels, which are responsible for NO and PGE2 production, respectively, in RAW264.7 macrophage cells. Because inflammation is linked to the activation of the coagulation system, we hypothesized that RVS and its active component fisetin possess anticoagulatory activities. As expected, we found that both RVS and fisetin could inhibit the coagulation of human peripheral blood cells. Moreover, in vivo RVS treatment could return the retarded blood flow elicited by a high-fat diet (HFD) back to the normal level in mice. In addition, RVS treatment has significantly reduced body weight gained by HFD in mice. Taken together, the fisetin-rich RVS extracts have potential antiplatelet and antiobesity activities and could be used as a functional food ingredient to improve blood circulation.

  12. Approach of the value of an annuity when non-central moments of the capitalization factor are known: an R application with interest rates following normal and beta distributions

    Directory of Open Access Journals (Sweden)

    Salvador Cruz Rambaud

    2015-07-01

    Full Text Available This paper proposes an expression of the value of an annuity with payments of 1 unit each when the interest rate is random. In order to attain this objective, we proceed on the assumption that the non-central moments of the capitalization factor are known. Specifically, to calculate the value of these annuities, we propose two different expressions. First, we suppose that the random interest rate is normally distributed; then, we assume that it follows the beta distribution. A practical application of these two methodologies is also implemented using the R statistical software.

  13. Advances and Challenges in Islet Transplantation: Islet Procurement Rates and Lessons Learned from Suboptimal Islet Transplantation

    OpenAIRE

    Annette Plesner; C. Bruce Verchere

    2011-01-01

    The initial step in successful islet transplantation is procurement of healthy donor islets. Given the limited number of donor pancreata selected for islet isolation and that islets from multiple donors are typically required to obtain insulin independence, it is critical to improve pancreas procurement rates and yield of islets for transplantation. Islets are delicate microorgans that are susceptible to apoptosis, hypoxia, and ischemia during isolation, culture, and the peritransplant period...

  14. Differentiating inflamed and normal lungs by the apparent reaction rate constants of lactate dehydrogenase probed by hyperpolarized (13)C labeled pyruvate.

    Science.gov (United States)

    Xu, He N; Kadlececk, Stephen; Shaghaghi, Hoora; Zhao, Huaqing; Profka, Harilla; Pourfathi, Mehrdad; Rizi, Rahim; Li, Lin Z

    2016-02-01

    Clinically translatable hyperpolarized (HP) (13)C-NMR can probe in vivo enzymatic reactions, e.g., lactate dehydrogenase (LDH)-catalyzed reaction by injecting HP (13)C-pyruvate into the subject, which is converted to (13)C labeled lactate by the enzyme. Parameters such as (13)C-lactate signals and lactate-to-pyruvate signal ratio are commonly used for analyzing the HP (13)C-NMR data. However, the biochemical/biological meaning of these parameters remains either unclear or dependent on experimental settings. It is preferable to quantify the reaction rate constants with a clearer physical meaning. Here we report the extraction of the kinetic parameters of the LDH reaction from HP (13)C-NMR data and investigate if they can be potential predictors of lung inflammation. Male Sprague-Dawley rats (12 controls, 14 treated) were used. One dose of bleomycin (2.5 U/kg) was administered intratracheally to the treatment group. The lungs were removed, perfused, and observed by the HP-NMR technique, where a HyperSense dynamic nuclear polarization system was used to generate the HP (13)C-pyruvate for injecting into the lungs. A 20 mm (1)H/(13)C dual-tuned coil in a 9.4-T Varian vertical bore NMR spectrometer was employed to acquire the (13)C spectral data every 1 s over a time period of 300 s using a non-selective, 15-degree radiofrequency pulse. The apparent rate constants of the LDH reaction and their ratio were quantified by applying ratiometric fitting analysis to the time series data of (13)C labeled pyruvate and lactate. The apparent forward rate constant kp =(3.67±3.31)×10(-4) s(-1), reverse rate constant kl =(4.95±2.90)×10(-2) s(-1), rate constant ratio kp /kl =(7.53±5.75)×10(-3) for the control lungs; kp =(11.71±4.35)×10(-4) s(-1), kl =(9.89±3.89)×10(-2) s(-1), and kp /kl =(12.39±4.18)×10(-3) for the inflamed lungs at the 7(th) day post treatment. Wilcoxon rank-sum test showed that the medians of these kinetic parameters of the 7-day cohort were significantly

  15. Quantifying long-term population growth rates of threatened bull trout: challenges, lessons learned, and opportunities

    Science.gov (United States)

    Budy, Phaedra; Bowerman, Tracy; Al-Chokhachy, Robert K.; Conner, Mary; Schaller, Howard

    2017-01-01

    Temporal symmetry models (TSM) represent advances in the analytical application of mark–recapture data to population status assessments. For a population of char, we employed 10 years of active and passive mark–recapture data to quantify population growth rates using different data sources and analytical approaches. Estimates of adult population growth rate were 1.01 (95% confidence interval = 0.84–1.20) using a temporal symmetry model (λTSM), 0.96 (0.68–1.34) based on logistic regressions of annual snorkel data (λA), and 0.92 (0.77–1.11) from redd counts (λR). Top-performing TSMs included an increasing time trend in recruitment (f) and changes in capture probability (p). There was only a 1% chance the population decreased ≥50%, and a 10% chance it decreased ≥30% (λMCMC; based on Bayesian Markov chain Monte Carlo procedure). Size structure was stable; however, the adult population was dominated by small adults, and over the study period there was a decline in the contribution of large adults to total biomass. Juvenile condition decreased with increasing adult densities. Utilization of these different information sources provided a robust weight-of-evidence approach to identifying population status and potential mechanisms driving changes in population growth rates.

  16. Normal accidents

    International Nuclear Information System (INIS)

    Perrow, C.

    1989-01-01

    The author has chosen numerous concrete examples to illustrate the hazardousness inherent in high-risk technologies. Starting with the TMI reactor accident in 1979, he shows that it is not only the nuclear energy sector that bears the risk of 'normal accidents', but also quite a number of other technologies and industrial sectors, or research fields. The author refers to the petrochemical industry, shipping, air traffic, large dams, mining activities, and genetic engineering, showing that due to the complexity of the systems and their manifold, rapidly interacting processes, accidents happen that cannot be thoroughly calculated, and hence are unavoidable. (orig./HP) [de

  17. Dissolution rates of unirradiated UO2, UO2 doped with 233U, and spent fuel under normal atmospheric conditions and under reducing conditions using an isotope dilution method

    International Nuclear Information System (INIS)

    Ollila, Kaija; Albinsson, Yngve; Oversby, Virginia; Cowper, Mark

    2003-10-01

    The experimental results given in this report allow us to draw the following conclusions. 1) Tests using unirradiated fuel pellet materials from two different manufacturers gave very different dissolution rates under air atmosphere testing. Tests for fragments of pellets from different pellets made by the same manufacturer gave good agreement. This indicates that details of the manufacturing process have a large effect on the behavior of unirradiated UO 2 in dissolution experiments. Care must be taken in interpreting differences in results obtained in different laboratories because the results may be affected by manufacturing effects. 2) Long-term tests under air atmosphere have begun to show the effects of precipitation. Further testing will be needed before the samples reach steady state. 3) Testing of unirradiated UO 2 in systems containing an iron strip to produce reducing conditions gave [U] less than detection limits ( 235 U added as spike was recovered, indicating that 90% of the spike had precipitated onto the solid sample or the iron strip. 9) Tests of UO 2 pellet materials containing 233 U to provide an alpha decay activity similar to that expected for spent fuel 3000 and 10,000 years after disposal showed that the pellet materials behaved as expected under air atmosphere conditions, showing that the manufacturing method was successful. 10) Early testing of the 233 U-doped materials under reducing conditions showed relatively rapid (30 minute) dissolution of small amounts of U at the start of the puff test procedure. Results of analyses of an acidified fraction of the same solutions after 1 or 2 weeks holding indicate that the solutions were inhomogeneous, indicating the presence of colloidal material or small grains of solid. 11) Samples from the 233 U-doped tests initially indicated dissolution of solid during the first week of testing, with some indication of more rapid dissolution of the material with the higher doping. 12) The second cycle of testing

  18. Different slopes for different folks: alpha and delta EEG power predict subsequent video game learning rate and improvements in cognitive control tasks.

    Science.gov (United States)

    Mathewson, Kyle E; Basak, Chandramallika; Maclin, Edward L; Low, Kathy A; Boot, Walter R; Kramer, Arthur F; Fabiani, Monica; Gratton, Gabriele

    2012-12-01

    We hypothesized that control processes, as measured using electrophysiological (EEG) variables, influence the rate of learning of complex tasks. Specifically, we measured alpha power, event-related spectral perturbations (ERSPs), and event-related brain potentials during early training of the Space Fortress task, and correlated these measures with subsequent learning rate and performance in transfer tasks. Once initial score was partialled out, the best predictors were frontal alpha power and alpha and delta ERSPs, but not P300. By combining these predictors, we could explain about 50% of the learning rate variance and 10%-20% of the variance in transfer to other tasks using only pretraining EEG measures. Thus, control processes, as indexed by alpha and delta EEG oscillations, can predict learning and skill improvements. The results are of potential use to optimize training regimes. Copyright © 2012 Society for Psychophysiological Research.

  19. Standardisation of tracer and type of meal in the evaluation of gastric emptying and colon transit rates in normal Beagle dogs

    International Nuclear Information System (INIS)

    Dormehl, I.C.; Jordaan, J.H.; Jacobs, D.J.; Plessis, M. du; Pilloy, W.

    1984-01-01

    The transit of 111 In-labelled polymer beads of different particle sizes in the stomach and colon of five healthy Beagle dogs was monitored after intake of different kinds of meal by a gamma camera and data processor system. The various meals studied were a solid balanced type of dog food mixed with molk, pure milk, and finally a metal of raw meat. The polymer beads carried triethylenetetramine type functions which efficiently chelated 111 In +3 from an aqueous solution of InCl 3 . These labelled beads were well mixed into the food before being offered to the dogs. Gastric emptying curves from which half-times of emptying (Tsub(1/2)) could be obtained are presented and statistically compared. Good quality images with quantification of the colon transit rate also became possible. It appeared that standardisation of the tracer and of the metal is compulsory for relevant and reproducible results. (orig.)

  20. Standardisation of tracer and type of meal in the evaluation of gastric emptying and colon transit rates in normal Beagle dogs

    Energy Technology Data Exchange (ETDEWEB)

    Dormehl, I.C.; Jordaan, J.H.; Jacobs, D.J.; Plessis, M. du; Pilloy, W.

    1984-01-01

    The transit of /sup 111/In-labelled polymer beads of different particle sizes in the stomach and colon of five healthy Beagle dogs was monitored after intake of different kinds of meal by a gamma camera and data processor system. The various meals studied were a solid balanced type of dog food mixed with molk, pure milk, and finally a meal of raw meat. The polymer beads carried triethylenetetramine type functions which efficiently chelated /sup 111/In/sup +3/ from an aqueous solution of InCl/sub 3/. These labelled beads were well mixed into the food before being offered to the dogs. Gastric emptying curves from which half-times of emptying (Tsub(1/2)) could be obtained are presented and statistically compared. Good quality images with quantification of the colon transit rate also became possible. It appeared that standardisation of the tracer and of the metal is compulsory for relevant and reproducible results.

  1. Measurement of fission gas release, internal pressure and cladding creep rate in the fuel pins of PHWR bundle of normal discharge burnup

    Energy Technology Data Exchange (ETDEWEB)

    Viswanathan, U.K. [Post Irradiation Examination Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Sah, D.N., E-mail: dnsah@barc.gov.i [Post Irradiation Examination Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Rath, B.N.; Anantharaman, S. [Post Irradiation Examination Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2009-08-01

    Fuel pins of a Pressurised Heavy Water Reactor (PHWR) fuel bundle discharged from Narora Atomic Power Station unit no. 1 after attaining a fuel burnup of 7528 MWd/tU have been subjected to two types of studies, namely (i) puncture test to estimate extent of fission gas release and internal pressure in the fuel pin and (ii) localized heating of the irradiated fuel pin to measure the creep rate of the cladding in temperature range 800 deg. C - 900 deg. C. The fission gas release in the fuel pins from the outer ring of the bundle was found to be about 8%. However, only marginal release was found in fuel pins from the middle ring and the central fuel pin. The internal gas pressure in the outer fuel pin was measured to be 0.55 +- 0.05 MPa at room temperature. In-cell isothermal heating of a small portion of the outer fuel pins was carried out at 800 deg. C, 850 deg. C and 900 deg. C for 10 min and the increase in diameter of the fuel pin was measured after heat treatment. Creep rates of the cladding obtained from the measurement of the diameter change of the cladding due to heating at 800 deg. C, 850 deg. C and 900 deg. C were found respectively to be 2.4 x 10{sup -5} s{sup -1}, 24.6 x 10{sup -5} s{sup -1} and 45.6 x 10{sup -5} s{sup -1}.

  2. Effect of ST36 Acupuncture on Hyperventilation-Induced CO2 Reactivity of the Basilar and Middle Cerebral Arteries and Heart Rate Variability in Normal Subjects

    Directory of Open Access Journals (Sweden)

    Sang-Ho Hyun

    2014-01-01

    Full Text Available This study was conducted to verify the effect of acupuncture on cerebral haemodynamics to provide evidence for the use of acupuncture treatment as a complementary therapy for the high-risk stroke population. The effect of ST36 acupuncture treatment on the hyperventilation-induced CO2 reactivity of the basilar and middle cerebral arteries was studied in 10 healthy male volunteers (mean age, 25.2 ± 1.5 years using a transcranial Doppler sonography with an interval of 1 week between measurements, and a portable ECG monitoring system was used to obtain ECG data simultaneously. The CO2 reactivity of the basilar and middle cerebral arteries increased significantly after ST36 acupuncture treatment, whereas the mean arterial blood pressure and pulse rate did not change significantly. The high-frequency power significantly increased after ST36 acupuncture treatment, and the percentage increase of high-frequency power correlated significantly with the percentage increase in the CO2 reactivity of the contralateral middle cerebral artery. These data suggest that ST36 acupuncture treatment increases CO2 reactivity, indicating improvement of vasodilatory potential of the cerebral vasculature to compensate for fluctuations caused by changes in external conditions. The increase in parasympathetic tone by ST36 acupuncture treatment is responsible for this therapeutic effect.

  3. A mathematical model resolving normal human blood lymphocyte population X-ray survival curves into six components: radiosensitivity, death rate and size of two responding sub-populations

    International Nuclear Information System (INIS)

    Thomson, A.E.R.; Vaughan-Smith, S.; Peel, W.E.

    1982-01-01

    The analysis was based on observations of survival decrease as a function of dose (range 0-5 Gy (= 500 rad)) and time after irradiation in vitro. Since lymphocyte survival is also sensitive to culture conditions the effects of radiation were examined daily up to 3 days only, while survival of control cells remained ca. 90 per cent. The time-dependent changes were resolved as the death rates (first-order governed) of lethally-hit cells (apparent survivors), so rendering these distinguishable from the morphologically identical, true (ultimate) survivors. For 12 blood donors the estimated dose permitting 37 per cent ultimate survival (D 37 value) averaged 0.72 +- 0.18 (SD) Gy for the more radiosensitive lymphocyte fraction and 2.50 +- 0.67 Gy for the less radiosensitive, each fraction proving homogeneously radiosensitive and the latter identifying substantially in kind with T-type (E-rosetting lymphocytes). The half-life of lethally-hit members of either fraction varied widely among the donors (ranges, 25-104 hours and 11-40 hours, respectively). Survival curves reconstructed by summating the numerical estimates of the six parameters according to the theoretical model closely matched those observed experimentally (ranged in multiple correlation coefficient, 0.9709-0.9994) for all donors). This signified the absence of any additional, totally radioresistant cell fraction. (author)

  4. Reconstructing Normality

    DEFF Research Database (Denmark)

    Gildberg, Frederik Alkier; Bradley, Stephen K.; Fristed, Peter Billeskov

    2012-01-01

    Forensic psychiatry is an area of priority for the Danish Government. As the field expands, this calls for increased knowledge about mental health nursing practice, as this is part of the forensic psychiatry treatment offered. However, only sparse research exists in this area. The aim of this study...... was to investigate the characteristics of forensic mental health nursing staff interaction with forensic mental health inpatients and to explore how staff give meaning to these interactions. The project included 32 forensic mental health staff members, with over 307 hours of participant observations, 48 informal....... The intention is to establish a trusting relationship to form behaviour and perceptual-corrective care, which is characterized by staff's endeavours to change, halt, or support the patient's behaviour or perception in relation to staff's perception of normality. The intention is to support and teach the patient...

  5. Pursuing Normality

    DEFF Research Database (Denmark)

    Madsen, Louise Sofia; Handberg, Charlotte

    2018-01-01

    implying an influence on whether to participate in cancer survivorship care programs. Because of "pursuing normality," 8 of 9 participants opted out of cancer survivorship care programming due to prospects of "being cured" and perceptions of cancer survivorship care as "a continuation of the disease......BACKGROUND: The present study explored the reflections on cancer survivorship care of lymphoma survivors in active treatment. Lymphoma survivors have survivorship care needs, yet their participation in cancer survivorship care programs is still reported as low. OBJECTIVE: The aim of this study...... was to understand the reflections on cancer survivorship care of lymphoma survivors to aid the future planning of cancer survivorship care and overcome barriers to participation. METHODS: Data were generated in a hematological ward during 4 months of ethnographic fieldwork, including participant observation and 46...

  6. The learning curve to achieve satisfactory completion rates in upper GI endoscopy: an analysis of a national training database.

    Science.gov (United States)

    Ward, S T; Hancox, A; Mohammed, M A; Ismail, T; Griffiths, E A; Valori, R; Dunckley, P

    2017-06-01

    The aim of this study was to determine the number of OGDs (oesophago-gastro-duodenoscopies) trainees need to perform to acquire competency in terms of successful unassisted completion to the second part of the duodenum 95% of the time. OGD data were retrieved from the trainee e-portfolio developed by the Joint Advisory Group on GI Endoscopy (JAG) in the UK. All trainees were included unless they were known to have a baseline experience of >20 procedures or had submitted data for 90% trainees had attained a 95% completion rate. Total number of OGDs performed, trainee age and experience in lower GI endoscopy were factors independently associated with OGD completion. There are limited published data on the OGD learning curve. This is the largest study to date analysing the learning curve for competency acquisition. The JAG competency requirement for 200 procedures appears appropriate. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  7. Reduced white matter MRI transverse relaxation rate in cognitively normal H63D-HFE human carriers and H67D-HFE mice.

    Science.gov (United States)

    Meadowcroft, Mark D; Wang, Jianli; Purnell, Carson J; Peters, Douglas G; Eslinger, Paul J; Neely, Elizabeth B; Gill, David J; Vasavada, Megha; Ali-Rahmani, Fatima; Yang, Qing X; Connor, James R

    2016-12-01

    Mutations within the HFE protein gene sequence have been associated with increased risk of developing a number of neurodegenerative disorders. To this effect, an animal model has been created which incorporates the mouse homologue to the human H63D-HFE mutation: the H67D-HFE knock-in mouse. These mice exhibit alterations in iron management proteins, have increased neuronal oxidative stress, and a disruption in cholesterol regulation. However, it remains undetermined how these differences translate to human H63D carriers in regards to white matter (WM) integrity. To this endeavor, MRI transverse relaxation rate (R 2 ) parametrics were employed to test the hypothesis that WM alterations are present in H63D human carriers and are recapitulated in the H67D mice. H63D carriers exhibit widespread reductions in brain R 2 compared to non-carriers within white matter association fibers in the brain. Similar R 2 decreases within white matter tracts were observed in the H67D mouse brain. Additionally, an exacerbation of age-related R 2 decrease is found in the H67D animal model in white matter regions of interest. The decrease in R 2 within white matter tracts of both species is speculated to be multifaceted. The R 2 changes are hypothesized to be due to alterations in axonal biochemical tissue composition. The R 2 changes observed in both the human-H63D and mouse-H67D data suggest that modified white matter myelination is occurring in subjects with HFE mutations, potentially increasing vulnerability to neurodegenerative disorders.

  8. Assessment of Adaptive Rate Response Provided by Accelerometer, Minute Ventilation and Dual Sensor Compared with Normal Sinus Rhythm During Exercise: A Self-controlled Study in Chronotropically Competent Subjects

    Directory of Open Access Journals (Sweden)

    Yuanyuan Cao

    2015-01-01

    Full Text Available Background: Dual sensor (DS for rate adaption was supposed to be more physiological. To evaluate its superiority, the DS (accelerometer [ACC] and minute ventilation [MV] and normal sinus rate response were compared in a self-controlled way during exercise treadmill testing. Methods: This self-controlled study was performed in atrioventricular block patients with normal sinus function who met the indications of pacemaker implant. Twenty-one patients came to the 1-month follow-up visit. Patients performed a treadmill test 1-month post implant while programmed in DDDR and sensor passive mode. For these patients, sensor response factors were left at default settings (ACC = 8, MV = 3 and sensor indicated rates (SIRs for DS, ACC and MV sensor were retrieved from the pacemaker memories, along with measured sinus node (SN rates from the beginning to 1-minute after the end of the treadmill test, and compared among study groups. Repeated measures analysis of variance and profile analysis, as well as variance analysis of randomized block designs, were used for statistical analysis. Results: Fifteen patients (15/21 were determined to be chronotropically competent. The mean differences between DS SIRs and intrinsic sinus rates during treadmill testing were smaller than those for ACC and MV sensor (mean difference between SIR and SN rate: ACC vs. SN, MV vs. SN, DS vs. SN, respectively, 34.84, 17.60, 16.15 beats/min, though no sensors could mimic sinus rates under the default settings for sensor response factor (ACC vs. SN P-adjusted < 0.001; MV vs. SN P-adjusted = 0.002; DS vs. SN P-adjusted = 0.005. However, both in the range of 1 st minute and first 3 minutes of exercise, only the DS SIR profile did not differ from sinus rates (P-adjusted = 0.09, 0.90, respectively. Conclusions: The DS under default settings provides more physiological rate response during physical activity than the corresponding single sensors (ACC or MV sensor. Further study is needed to

  9. Utilizing Learners' Negative Ratings in Semantic Content-Based Recommender System for e-Learning Forum

    Science.gov (United States)

    Albatayneh, Naji Ahmad; Ghauth, Khairil Imran; Chua, Fang-Fang

    2018-01-01

    Nowadays, most of e-learning systems embody online discussion forums as a medium for collaborative learning that supports knowledge sharing and information exchanging between learners. The exponential growth of the available shared information in e-learning online discussion forums has caused a difficulty for learners in discovering interesting…

  10. Chunking and Consolidation: A Theoretical Synthesis of Semantic Networks, Configuring in Conditioning, S--R Versus Cognitive Learning, Normal Forgetting, the Amnesic Syndrome, and the Hippocampal Arousal System.

    Science.gov (United States)

    Wickelgren, Wayne A.

    1979-01-01

    The relationship between current information processing and prior associative theories of human and animal learning, memory, and amnesia are discussed. The paper focuses on the two components of the amnesic syndrome, retrograde amnesia and anterograde amnesia. A neural theory of chunking and consolidation is proposed. (Author/RD)

  11. Wind Turbine Driving a PM Synchronous Generator Using Novel Recurrent Chebyshev Neural Network Control with the Ideal Learning Rate

    Directory of Open Access Journals (Sweden)

    Chih-Hong Lin

    2016-06-01

    Full Text Available A permanent magnet (PM synchronous generator system driven by wind turbine (WT, connected with smart grid via AC-DC converter and DC-AC converter, are controlled by the novel recurrent Chebyshev neural network (NN and amended particle swarm optimization (PSO to regulate output power and output voltage in two power converters in this study. Because a PM synchronous generator system driven by WT is an unknown non-linear and time-varying dynamic system, the on-line training novel recurrent Chebyshev NN control system is developed to regulate DC voltage of the AC-DC converter and AC voltage of the DC-AC converter connected with smart grid. Furthermore, the variable learning rate of the novel recurrent Chebyshev NN is regulated according to discrete-type Lyapunov function for improving the control performance and enhancing convergent speed. Finally, some experimental results are shown to verify the effectiveness of the proposed control method for a WT driving a PM synchronous generator system in smart grid.

  12. Effect of Vicarious Fear Learning on Children’s Heart Rate Responses and Attentional Bias for Novel Animals

    Science.gov (United States)

    2014-01-01

    Research with children has shown that vicarious learning can result in changes to 2 of Lang’s (1968) 3 anxiety response systems: subjective report and behavioral avoidance. The current study extended this research by exploring the effect of vicarious learning on physiological responses (Lang’s final response system) and attentional bias. The study used Askew and Field’s (2007) vicarious learning procedure and demonstrated fear-related increases in children’s cognitive, behavioral, and physiological responses. Cognitive and behavioral changes were retested 1 week and 1 month later, and remained elevated. In addition, a visual search task demonstrated that fear-related vicarious learning creates an attentional bias for novel animals, which is moderated by increases in fear beliefs during learning. The findings demonstrate that vicarious learning leads to lasting changes in all 3 of Lang’s anxiety response systems and is sufficient to create attentional bias to threat in children. PMID:25151521

  13. The Effect of Active Learning Techniques on Class Teacher Candidates' Success Rates and Attitudes toward Their Museum Theory and Application Unit in Their Visual Arts Course

    Science.gov (United States)

    Dilmac, Oguz

    2016-01-01

    The purpose of this study is to examine the effect that using active learning techniques during museum and gallery visits has on teacher candidates' academic success rates in and attitudes toward their Visual Arts Course. In this study, the importance and requirement of education to take place in museums and art galleries is emphasized. The…

  14. Glucose Injections into the Dorsal Hippocampus or Dorsolateral Striatum of Rats Prior to T-Maze Training: Modulation of Learning Rates and Strategy Selection

    Science.gov (United States)

    Canal, Clinton E.; Stutz, Sonja J.; Gold, Paul E.

    2005-01-01

    The present experiments examined the effects of injecting glucose into the dorsal hippocampus or dorsolateral striatum on learning rates and on strategy selection in rats trained on a T-maze that can be solved by using either a hippocampus-sensitive place or striatum-sensitive response strategy. Percentage strategy selection on a probe trial…

  15. A combination of high dose rate (10X FFF/2400 MU/min/10 MV X-rays) and total low dose (0.5 Gy) induces a higher rate of apoptosis in melanoma cells in vitro and superior preservation of normal melanocytes.

    Science.gov (United States)

    Sarojini, Sreeja; Pecora, Andrew; Milinovikj, Natasha; Barbiere, Joseph; Gupta, Saakshi; Hussain, Zeenathual M; Tuna, Mehmet; Jiang, Jennifer; Adrianzen, Laura; Jun, Jaewook; Catello, Laurice; Sanchez, Diana; Agarwal, Neha; Jeong, Stephanie; Jin, Youngjin; Remache, Yvonne; Goy, Andre; Ndlovu, Alois; Ingenito, Anthony; Suh, K Stephen

    2015-10-01

    The aim of this study was to determine the apoptotic effects, toxicity, and radiosensitization of total low dose irradiation delivered at a high dose rate in vitro to melanoma cells, normal human epidermal melanocytes (HEM), or normal human dermal fibroblasts (HDF) and to study the effect of mitochondrial inhibition in combination with radiation to enhance apoptosis in melanoma cells. Cells irradiated using 10X flattening filter-free (FFF) 10 MV X-rays at a dose rate of 400 or 2400 MU/min and a total dose of 0.25-8 Gy were analyzed by cell/colony counting, MitoTracker, MTT, and DNA-damage assays, as well as by quantitative real-time reverse transcriptase PCR in the presence or absence of mitochondrial respiration inhibitors. A dose rate of 2400 MU/min killed on average five-fold more melanoma cells than a dose rate 400 MU/min at a total dose of 0.5 Gy and preserved 80% survival of HEM and 90% survival of HDF. Increased apoptosis at the 2400 MU/min dose rate is mediated by greater DNA damage, reduced cell proliferation, upregulation of apoptotic genes, and downregulation of cell cycle genes. HEM and HDF were relatively unharmed at 2400 MU/min. Radiation induced upregulation of mitochondrial respiration in both normal and cancer cells, and blocking the respiration with inhibitors enhanced apoptosis only in melanoma cells. A high dose rate with a low total dose (2400 MU/min, 0.5 Gy/10X FFF 10 MV X-rays) enhances radiosensitivity of melanoma cells while reducing radiotoxicity toward HEM and HDF. Selective cytotoxicity of melanoma cells is increased by blocking mitochondrial respiration.

  16. Impact of deep learning on the normalization of reconstruction kernel effects in imaging biomarker quantification: a pilot study in CT emphysema

    Science.gov (United States)

    Jin, Hyeongmin; Heo, Changyong; Kim, Jong Hyo

    2018-02-01

    Differing reconstruction kernels are known to strongly affect the variability of imaging biomarkers and thus remain as a barrier in translating the computer aided quantification techniques into clinical practice. This study presents a deep learning application to CT kernel conversion which converts a CT image of sharp kernel to that of standard kernel and evaluates its impact on variability reduction of a pulmonary imaging biomarker, the emphysema index (EI). Forty cases of low-dose chest CT exams obtained with 120kVp, 40mAs, 1mm thickness, of 2 reconstruction kernels (B30f, B50f) were selected from the low dose lung cancer screening database of our institution. A Fully convolutional network was implemented with Keras deep learning library. The model consisted of symmetric layers to capture the context and fine structure characteristics of CT images from the standard and sharp reconstruction kernels. Pairs of the full-resolution CT data set were fed to input and output nodes to train the convolutional network to learn the appropriate filter kernels for converting the CT images of sharp kernel to standard kernel with a criterion of measuring the mean squared error between the input and target images. EIs (RA950 and Perc15) were measured with a software package (ImagePrism Pulmo, Seoul, South Korea) and compared for the data sets of B50f, B30f, and the converted B50f. The effect of kernel conversion was evaluated with the mean and standard deviation of pair-wise differences in EI. The population mean of RA950 was 27.65 +/- 7.28% for B50f data set, 10.82 +/- 6.71% for the B30f data set, and 8.87 +/- 6.20% for the converted B50f data set. The mean of pair-wise absolute differences in RA950 between B30f and B50f is reduced from 16.83% to 1.95% using kernel conversion. Our study demonstrates the feasibility of applying the deep learning technique for CT kernel conversion and reducing the kernel-induced variability of EI quantification. The deep learning model has a

  17. The Multimedia-Based Learning System Improved Cognitive Skills and Motivation of Disabled Children with a Very High Rate

    Science.gov (United States)

    Saad, Sawsan; Dandashi, Amal; Aljaam, Jihad M.; Saleh, Moataz

    2015-01-01

    A multimedia-based learning system to teach children with intellectual disabilities (ID) the basic living and science concepts is proposed. The tutorials' development is pedagogically based on Mayer's Cognitive Theory of Multimedia Learning combined with Skinner's Operant Conditioning Model. Two types of tutorials are proposed. In the first type;…

  18. An Advanced Deep Learning Approach for Ki-67 Stained Hotspot Detection and Proliferation Rate Scoring for Prognostic Evaluation of Breast Cancer.

    Science.gov (United States)

    Saha, Monjoy; Chakraborty, Chandan; Arun, Indu; Ahmed, Rosina; Chatterjee, Sanjoy

    2017-06-12

    Being a non-histone protein, Ki-67 is one of the essential biomarkers for the immunohistochemical assessment of proliferation rate in breast cancer screening and grading. The Ki-67 signature is always sensitive to radiotherapy and chemotherapy. Due to random morphological, color and intensity variations of cell nuclei (immunopositive and immunonegative), manual/subjective assessment of Ki-67 scoring is error-prone and time-consuming. Hence, several machine learning approaches have been reported; nevertheless, none of them had worked on deep learning based hotspots detection and proliferation scoring. In this article, we suggest an advanced deep learning model for computerized recognition of candidate hotspots and subsequent proliferation rate scoring by quantifying Ki-67 appearance in breast cancer immunohistochemical images. Unlike existing Ki-67 scoring techniques, our methodology uses Gamma mixture model (GMM) with Expectation-Maximization for seed point detection and patch selection and deep learning, comprises with decision layer, for hotspots detection and proliferation scoring. Experimental results provide 93% precision, 0.88% recall and 0.91% F-score value. The model performance has also been compared with the pathologists' manual annotations and recently published articles. In future, the proposed deep learning framework will be highly reliable and beneficial to the junior and senior pathologists for fast and efficient Ki-67 scoring.

  19. Intraoperative stroke volume optimization using stroke volume, arterial pressure, and heart rate: closed-loop (learning intravenous resuscitator) versus anesthesiologists.

    Science.gov (United States)

    Rinehart, Joseph; Chung, Elena; Canales, Cecilia; Cannesson, Maxime

    2012-10-01

    The authors compared the performance of a group of anesthesia providers to closed-loop (Learning Intravenous Resuscitator [LIR]) management in a simulated hemorrhage scenario using cardiac output monitoring. A prospective cohort study. In silico simulation. University hospital anesthesiologists and the LIR closed-loop fluid administration system. Using a patient simulator, a 90-minute simulated hemorrhage protocol was run, which included a 1,200-mL blood loss over 30 minutes. Twenty practicing anesthesiology providers were asked to manage this scenario by providing fluids and vasopressor medication at their discretion. The simulation program was also run 20 times with the LIR closed-loop algorithm managing fluids and an additional 20 times with no intervention. Simulated patient weight, height, heart rate, mean arterial pressure, and cardiac output (CO) were similar at baseline. The mean stroke volume, the mean arterial pressure, CO, and the final CO were higher in the closed-loop group than in the practitioners group, and the coefficient of variance was lower. The closed-loop group received slightly more fluid (2.1 v 1.9 L, p closed-loop maintained more stable hemodynamics than the practitioners primarily because the fluid was given earlier in the protocol and CO optimized before the hemorrhage began, whereas practitioners tended to resuscitate well but only after significant hemodynamic change indicated the need. Overall, these data support the potential usefulness of this closed-loop algorithm in clinical settings in which dynamic predictors are not available or applicable. Published by Elsevier Inc.

  20. Difference in the craniocaudal gradient of the maximum pixel value change rate between chronic obstructive pulmonary disease patients and normal subjects using sub-mGy dynamic chest radiography with a flat panel detector system.

    Science.gov (United States)

    Yamada, Yoshitake; Ueyama, Masako; Abe, Takehiko; Araki, Tetsuro; Abe, Takayuki; Nishino, Mizuki; Jinzaki, Masahiro; Hatabu, Hiroto; Kudoh, Shoji

    2017-07-01

    To compare the craniocaudal gradients of the maximum pixel value change rate (MPCR) during tidal breathing between chronic obstructive pulmonary disease (COPD) patients and normal subjects using dynamic chest radiography. This prospective study was approved by the institutional review board and all participants provided written informed consent. Forty-three COPD patients (mean age, 71.6±8.7 years) and 47 normal subjects (non-smoker healthy volunteers) (mean age, 54.8±9.8 years) underwent sequential chest radiographs during tidal breathing in a standing position using dynamic chest radiography with a flat panel detector system. We evaluated the craniocaudal gradient of MPCR. The results were analyzed using an unpaired t-test and the Tukey-Kramer method. The craniocaudal gradients of MPCR in COPD patients were significantly lower than those in normal subjects (right inspiratory phase, 75.5±48.1 vs. 108.9±42.0s -1 cm -1 , P<0.001; right expiratory phase, 66.4±40.6 vs. 89.8±31.6s -1 cm -1 , P=0.003; left inspiratory phase, 75.5±48.2 vs. 108.2±47.2s -1 cm -1 , P=0.002; left expiratory phase, 60.9±38.2 vs. 84.3±29.5s -1 cm -1 , P=0.002). No significant differences in height, weight, or BMI were observed between COPD and normal groups. In the sub-analysis, the gradients in severe COPD patients (global initiative for chronic obstructive lung disease [GOLD] 3 or 4, n=26) were significantly lower than those in mild COPD patients (GOLD 1 or 2, n=17) for both right and left inspiratory/expiratory phases (all P≤0.005). A decrease of the craniocaudal gradient of MPCR was observed in COPD patients. The craniocaudal gradient was lower in severe COPD patients than in mild COPD patients. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  1. The Normal Fetal Pancreas.

    Science.gov (United States)

    Kivilevitch, Zvi; Achiron, Reuven; Perlman, Sharon; Gilboa, Yinon

    2017-10-01

    The aim of the study was to assess the sonographic feasibility of measuring the fetal pancreas and its normal development throughout pregnancy. We conducted a cross-sectional prospective study between 19 and 36 weeks' gestation. The study included singleton pregnancies with normal pregnancy follow-up. The pancreas circumference was measured. The first 90 cases were tested to assess feasibility. Two hundred ninety-seven fetuses of nondiabetic mothers were recruited during a 3-year period. The overall satisfactory visualization rate was 61.6%. The intraobserver and interobserver variability had high interclass correlation coefficients of of 0.964 and 0.967, respectively. A cubic polynomial regression described best the correlation of pancreas circumference with gestational age (r = 0.744; P pancreas circumference percentiles for each week of gestation were calculated. During the study period, we detected 2 cases with overgrowth syndrome and 1 case with an annular pancreas. In this study, we assessed the feasibility of sonography for measuring the fetal pancreas and established a normal reference range for the fetal pancreas circumference throughout pregnancy. This database can be helpful when investigating fetomaternal disorders that can involve its normal development. © 2017 by the American Institute of Ultrasound in Medicine.

  2. IMPROVING STUDENTS’ GENERIC SKILL IN SCIENCE THROUGH CHEMISTRY LEARNING USING ICT-BASED MEDIA ON REACTION RATE AND OSMOTIC PRESSURE MATERIAL

    Directory of Open Access Journals (Sweden)

    S. Mulyani

    2016-04-01

    Full Text Available The research aims to obtain information of improvement students’ generic skills in science through chemistry learning using ICT-based media on reaction rate and osmotic pressure material. This research was designed with quasi-experimental research method, with the design of non-equivalent control group pretest-posttest design. The research subjects were students of class XI and XII one of Madrasah Aliyah Negeri (State Islamic Senior High School in Bandung. Learning process in experiment group were conducted using ICT-based media, whereas in control group conducted by applying laboratory activities. Data were collected through multiple-choice test. The result shows that there was no significant difference of n- gain of students’ generic skill in science between experiment and control group. Therefore it can be concluded that the learning process using ICT-based media can improve students' generic skills in science as well as laboratory-based activities.

  3. Normal Pressure Hydrocephalus (NPH)

    Science.gov (United States)

    ... local chapter Join our online community Normal Pressure Hydrocephalus (NPH) Normal pressure hydrocephalus is a brain disorder ... Symptoms Diagnosis Causes & risks Treatments About Normal Pressure Hydrocephalus Normal pressure hydrocephalus occurs when excess cerebrospinal fluid ...

  4. Learning

    Directory of Open Access Journals (Sweden)

    Mohsen Laabidi

    2014-01-01

    Full Text Available Nowadays learning technologies transformed educational systems with impressive progress of Information and Communication Technologies (ICT. Furthermore, when these technologies are available, affordable and accessible, they represent more than a transformation for people with disabilities. They represent real opportunities with access to an inclusive education and help to overcome the obstacles they met in classical educational systems. In this paper, we will cover basic concepts of e-accessibility, universal design and assistive technologies, with a special focus on accessible e-learning systems. Then, we will present recent research works conducted in our research Laboratory LaTICE toward the development of an accessible online learning environment for persons with disabilities from the design and specification step to the implementation. We will present, in particular, the accessible version “MoodleAcc+” of the well known e-learning platform Moodle as well as new elaborated generic models and a range of tools for authoring and evaluating accessible educational content.

  5. Comparison of the image quality of digital radiography system and film screen system - Radiologist' rating of the visibility of normal anatomic - Structures in chest PA, Skull radiograph and K. U. B

    International Nuclear Information System (INIS)

    Song, Kounn Sik; Kim, Young Goo; Lee, Jong Beum; Kim, Kun Sang

    1987-01-01

    Digital image acquisition and display is widely used in computed tomography, ultrasonography, digital subtraction angiography, nuclear medicine and magnetic resonance image. But most of the radiological examinations performed in radiology department are made by using conventional system. The development of the digital radiography system is essential if totally digitized radiology department is desired. The advantages of digitizing the radiographic information are usually discussed in terms of PACS (picture archiving and communication system), furthermore there are many other advantages such as contrast modification, spatial filtering subtraction and superimposition of the images through the image processing by computer. Currently several approaches are under development or in clinical use, the most promising approach is the use of imaging plate composed of photostimulate phosphors such as barium fluorohalide crystal read with a He-Ne laser to produce digital radiographic images. Another promising approach is scan projection radiography. The authors performed the clinical study of comparing the image qualities of digital radiography system using scanning laser luminescence (FCR) and conventional film-screen system in chest PA, skull radiography and K. U. B. in terms of the visibility of the normal anatomic structure rating those (qualities) on a scale of 0 to 3 and obtained the following results. Normal contrast digital images are comparable to conventional film-screen images, but the images of high frequency enhancement is far superior to conventional film-screen especially in peripherally located structures such as skin, subcutaneous fat, musculoskeletal systems, nasal bone, inner and outer table of the skull including the diploic space, paranasal sinuses, nasopharynx and larynx, trachea and main bronchi, mediastinal structures, retrocardiac and subphrenic vascular markings. Another promising aspects of digital radiography system is its wide exposure latitude and

  6. Does rating the operation videos with a checklist score improve the effect of E-learning for bariatric surgical training? Study protocol for a randomized controlled trial.

    Science.gov (United States)

    De La Garza, Javier Rodrigo; Kowalewski, Karl-Friedrich; Friedrich, Mirco; Schmidt, Mona Wanda; Bruckner, Thomas; Kenngott, Hannes Götz; Fischer, Lars; Müller-Stich, Beat-Peter; Nickel, Felix

    2017-03-21

    Laparoscopic training has become an important part of surgical education. Laparoscopic Roux-en-Y gastric bypass (RYGB) is the most common bariatric procedure performed. Surgeons must be well trained prior to operating on a patient. Multimodality training is vital for bariatric surgery. E-learning with videos is a standard approach for training. The present study investigates whether scoring the operation videos with performance checklists improves learning effects and transfer to a simulated operation. This is a monocentric, two-arm, randomized controlled trial. The trainees are medical students from the University of Heidelberg in their clinical years with no prior laparoscopic experience. After a laparoscopic basic virtual reality (VR) training, 80 students are randomized into one of two arms in a 1:1 ratio to the checklist group (group A) and control group without a checklist (group B). After all students are given an introduction of the training center, VR trainer and laparoscopic instruments, they start with E-learning while watching explanations and videos of RYGB. Only group A will perform ratings with a modified Bariatric Objective Structured Assessment of Technical Skill (BOSATS) scale checklist for all videos watched. Group B watches the same videos without rating. Both groups will then perform an RYGB in the VR trainer as a primary endpoint and small bowel suturing as an additional test in the box trainer for evaluation. This study aims to assess if E-learning and rating bariatric surgical videos with a modified BOSATS checklist will improve the learning curve for medical students in an RYGB VR performance. This study may help in future laparoscopic and bariatric training courses. German Clinical Trials Register, DRKS00010493 . Registered on 20 May 2016.

  7. Evaluation of {sup 123}I-orthoiodohippurate single kidney clearance rate by renal sequential scintigraphy in a large cohort of likely normal subjects aged between 0 and 18 years

    Energy Technology Data Exchange (ETDEWEB)

    Imperiale, Alessio; Olianti, Catia; Comis, Giannetto; Cava, Giuseppe la [University of Florence, Nuclear Medicine Unit, Department of Clinical Pathophysiology, Florence (Italy)

    2006-12-15

    Age-related values of{sup 123}I-orthoiodohippurate (OIH) single kidney clearance rate (Cl) were estimated in a large cohort of likely normal children aged between 0 and 18 years. Among 4,111 children examined in the past 10 years, 917 were selected with the following inclusion criteria: (a) mild ultrasonographic hydronephrosis with right differential renal function (DRF) <53% and >47% (498 pts), (b) known or suspected urinary tract infection with normal ultrasound, serum creatinine and DMSA and DRF <53% and >47% (419 pts).{sup 123}I-OIH-Cl was assessed using a validated gamma camera method. Children were divided into 21 age classes: from 0 to 2 years, eight 3-month classes; from 2 to 14 years, twelve 1-year classes; from 14 to 18 years, one 4-year class. Cl, plotted against age, was fitted using an increasing function (y = a - be - cx). Mean{sup 123}I-OIH-Cl of 1,834 kidneys was 306{+-}22 ml/min/1.73 m{sup 2} BSA. Mean{sup 123}I-OIH-Cl of the right and left kidneys was 307{+-}23 and 305{+-}22 ml/min/1.73 m{sup 2} BSA, respectively (p<0.002). The best-fitting{sup 123}I-OIH-Cl growing function was: Cl=311-230e-0.69 x Age (months).{sup 123}I-OIH-Cl improved progressively starting from birth, reaching 96% and 98% of the mature value at 1 and 1.5 years, respectively.{sup 123}I-OIH-Cl at birth (age=0) was 81 ml/min/1.73 m{sup 2} BSA. After 18.6 days of life, the renal function had doubled its starting value, and it reached a plateau of 311 ml/min/1.73 m{sup 2} BSA at 2 years. This work represents a systematic evaluation of ERPF by a gamma camera method in a large cohort of selected likely normal paediatric subjects. (orig.)

  8. Hebbian learning in a model with dynamic rate-coded neurons: an alternative to the generative model approach for learning receptive fields from natural scenes.

    Science.gov (United States)

    Hamker, Fred H; Wiltschut, Jan

    2007-09-01

    Most computational models of coding are based on a generative model according to which the feedback signal aims to reconstruct the visual scene as close as possible. We here explore an alternative model of feedback. It is derived from studies of attention and thus, probably more flexible with respect to attentive processing in higher brain areas. According to this model, feedback implements a gain increase of the feedforward signal. We use a dynamic model with presynaptic inhibition and Hebbian learning to simultaneously learn feedforward and feedback weights. The weights converge to localized, oriented, and bandpass filters similar as the ones found in V1. Due to presynaptic inhibition the model predicts the organization of receptive fields within the feedforward pathway, whereas feedback primarily serves to tune early visual processing according to the needs of the task.

  9. On the validity of the Middlesex Hospital Questionnaire: a comparison of diagnostic self-ratings in psychiatric out-patients, general practice patients, and 'normals' based on the Hebrew version.

    Science.gov (United States)

    Dasberg, H; Shalif, I

    1978-09-01

    The short clinical diagnostic self-rating scale for psycho-neurotic patients (The Middlesex Hospital Questionnaire) was translated into everyday Hebrew and tested on 216 subjects for: (1) concurrent validity with clinical diagnoses; (2) discriminatory validity on a psychoneurotic gradient of psychiatric out-patients, general practice patients, and normal controls; (3) validity of subscales and discrete items using matrices of Spearman rank correlation coefficients; (4) construct validity using Guttman's smallest space analysis based on coefficients of similarity. The Hebrew MHQ was found to retain its validity and to be easily applicable in waiting-room situations. It is a useful method for generating and substantiating hypotheses on psychosomatic and psychosocial interrelationships. The MHQ seems to enable the expression of the 'neurotic load' of a general practice subpopulation as a centile on a scale, thereby corroborating previous epidemiological findings on the high prevalence of neurotic illness in general practice. There is reason to believe that the MHQ is a valid instrument for the analysis of symptom profiles of subjects involved in future drug trials.

  10. Normalization: A Preprocessing Stage

    OpenAIRE

    Patro, S. Gopal Krishna; Sahu, Kishore Kumar

    2015-01-01

    As we know that the normalization is a pre-processing stage of any type problem statement. Especially normalization takes important role in the field of soft computing, cloud computing etc. for manipulation of data like scale down or scale up the range of data before it becomes used for further stage. There are so many normalization techniques are there namely Min-Max normalization, Z-score normalization and Decimal scaling normalization. So by referring these normalization techniques we are ...

  11. The Rey Auditory Verbal Learning Test forced-choice recognition task: Base-rate data and norms.

    Science.gov (United States)

    Poreh, Amir; Bezdicek, Ondrej; Korobkova, Irina; Levin, Jennifer B; Dines, Philipp

    2016-01-01

    The present study describes a novel Forced-Choice Response (FCR) index for detecting poor effort on the Rey Auditory Verbal Learning Test (RAVLT). This retrospective study analyzes the performance of 4 groups on the new index: clinically referred patients with suspected dementia, forensic patients identified as not exhibiting adequate effort on other measures of response bias, students who simulated poor effort, and a large normative sample collected in the Gulf State of Oman. Using sensitivity and specificity analyses, the study shows that much like the California Verbal Learning Test-Second Edition FCR index, the RAVLT FCR index misses a proportion of individuals with inadequate effort (low sensitivity), but those who fail this measure are highly likely to be exhibiting poor effort (high specificity). The limitations and benefits of utilizing the RAVLT FCR index in clinical practice are discussed.

  12. Controlling the chaotic discrete-Hénon system using a feedforward neural network with an adaptive learning rate

    OpenAIRE

    GÖKCE, Kürşad; UYAROĞLU, Yılmaz

    2013-01-01

    This paper proposes a feedforward neural network-based control scheme to control the chaotic trajectories of a discrete-Hénon map in order to stay within an acceptable distance from the stable fixed point. An adaptive learning back propagation algorithm with online training is employed to improve the effectiveness of the proposed method. The simulation study carried in the discrete-Hénon system verifies the validity of the proposed control system.

  13. Changes in Rate of Learning in Autistic Children Following 9 Months on a Gluten-Free Diet.

    Science.gov (United States)

    Pontino, Jamie Lyn; Schaal, Kelly; Chambliss, Catherine

    This report discusses the outcomes of a study that investigated the effects of a gluten-free diet on three males with autism between the ages of 5 to 8 years old. All subjects were also participants in prior studies on the effects of the gluten-free diet on the learning processes of children with autism in an applied behavioral analysis program.…

  14. Early evaluation of cerebral metabolic rate of glucose (CMRglu) with {sup 18}F-FDG PET/CT and clinical assessment in idiopathic normal pressure hydrocephalus (INPH) patients before and after ventricular shunt placement: preliminary experience

    Energy Technology Data Exchange (ETDEWEB)

    Calcagni, Maria Lucia; Lavalle, Mariadea; Leccisotti, Lucia; Giordano, Alessandro [Universita Cattolica del Sacro Cuore, Institute of Nuclear Medicine, Rome (Italy); Mangiola, Annunziato; De Bonis, Pasquale; Anile, Carmelo [Universita Cattolica del Sacro Cuore, Institute of Neurosurgery, Rome (Italy); Indovina, Luca [Universita Cattolica del Sacro Cuore, Institute of Physics, Rome (Italy); Marra, Camillo [Universita Cattolica del Sacro Cuore, Institute of Neurology, Rome (Italy); Pelliccioni, Armando [Istituto Nazionale per l' Assicurazione contro gli Infortuni sul Lavoro (INAIL), Rome (Italy)

    2012-02-15

    We evaluated the relationships between the cerebral metabolic rate of glucose (CMRglu) measured by dynamic {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) and the clinical and neuropsychological assessment before and after the surgical procedure in idiopathic normal pressure hydrocephalus (INPH) patients. Eleven selected INPH patients underwent clinical assessment (modified Rankin scale, Krauss scale, Larsson categorization system and Stein-Langfitt scale), cognitive evaluation (Mini-Mental State Examination, MMSE) and dynamic {sup 18}F-FDG PET/CT scan 3 days before and 1 week after ventricular shunt placement. After shunting, the global CMRglu significantly increased (2.95 {+-} 0.44 vs 4.38 {+-} 0.68, p = 10{sup -7}) in all INPH patients with a mean percentage value of 48.7%. After shunting, no significant change was found in the Evans ratio whereas a significant decrease in all clinical scale scores was observed. Only a slight reduction in the MMSE was found. After shunting, a significant correlation between the global CMRglu value and clinical assessment was found (R {sup 2} = 0.75, p = 0.024); indeed all clinical scale scores varied (decreasing) and the CMRglu value also varied (increasing) in all INPH patients. Our preliminary data show that changes in the CMRglu are promptly reversible after surgery and that there is a relationship between the early metabolic changes and clinical symptoms, independently from the simultaneous changes in the ventricular size. The remarkable and prompt improvement in the global CMRglu and in symptoms may also have important implications for the current concept of ''neuronal plasticity'' and for the cells' reactivity in order to recover their metabolic function. (orig.)

  15. iPhone 4s photoplethysmography: which light color yields the most accurate heart rate and normalized pulse volume using the iPhysioMeter Application in the presence of motion artifact?

    Directory of Open Access Journals (Sweden)

    Kenta Matsumura

    Full Text Available Recent progress in information and communication technologies has made it possible to measure heart rate (HR and normalized pulse volume (NPV, which are important physiological indices, using only a smartphone. This has been achieved with reflection mode photoplethysmography (PPG, by using a smartphone's embedded flash as a light source and the camera as a light sensor. Despite its widespread use, the method of PPG is susceptible to motion artifacts as physical displacements influence photon propagation phenomena and, thereby, the effective optical path length. Further, it is known that the wavelength of light used for PPG influences the photon penetration depth and we therefore hypothesized that influences of motion artifact could be wavelength-dependant. To test this hypothesis, we made measurements in 12 healthy volunteers of HR and NPV derived from reflection mode plethysmograms recorded simultaneously at three different spectral regions (red, green and blue at the same physical location with a smartphone. We then assessed the accuracy of the HR and NPV measurements under the influence of motion artifacts. The analyses revealed that the accuracy of HR was acceptably high with all three wavelengths (all rs > 0.996, fixed biases: -0.12 to 0.10 beats per minute, proportional biases: r =  -0.29 to 0.03, but that of NPV was the best with green light (r = 0.791, fixed biases: -0.01 arbitrary units, proportional bias: r = 0.11. Moreover, the signal-to-noise ratio obtained with green and blue light PPG was higher than that of red light PPG. These findings suggest that green is the most suitable color for measuring HR and NPV from the reflection mode photoplethysmogram under motion artifact conditions. We conclude that the use of green light PPG could be of particular benefit in ambulatory monitoring where motion artifacts are a significant issue.

  16. Early evaluation of cerebral metabolic rate of glucose (CMRglu) with 18F-FDG PET/CT and clinical assessment in idiopathic normal pressure hydrocephalus (INPH) patients before and after ventricular shunt placement: preliminary experience

    International Nuclear Information System (INIS)

    Calcagni, Maria Lucia; Lavalle, Mariadea; Leccisotti, Lucia; Giordano, Alessandro; Mangiola, Annunziato; De Bonis, Pasquale; Anile, Carmelo; Indovina, Luca; Marra, Camillo; Pelliccioni, Armando

    2012-01-01

    We evaluated the relationships between the cerebral metabolic rate of glucose (CMRglu) measured by dynamic 18 F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) and the clinical and neuropsychological assessment before and after the surgical procedure in idiopathic normal pressure hydrocephalus (INPH) patients. Eleven selected INPH patients underwent clinical assessment (modified Rankin scale, Krauss scale, Larsson categorization system and Stein-Langfitt scale), cognitive evaluation (Mini-Mental State Examination, MMSE) and dynamic 18 F-FDG PET/CT scan 3 days before and 1 week after ventricular shunt placement. After shunting, the global CMRglu significantly increased (2.95 ± 0.44 vs 4.38 ± 0.68, p = 10 -7 ) in all INPH patients with a mean percentage value of 48.7%. After shunting, no significant change was found in the Evans ratio whereas a significant decrease in all clinical scale scores was observed. Only a slight reduction in the MMSE was found. After shunting, a significant correlation between the global CMRglu value and clinical assessment was found (R 2 = 0.75, p = 0.024); indeed all clinical scale scores varied (decreasing) and the CMRglu value also varied (increasing) in all INPH patients. Our preliminary data show that changes in the CMRglu are promptly reversible after surgery and that there is a relationship between the early metabolic changes and clinical symptoms, independently from the simultaneous changes in the ventricular size. The remarkable and prompt improvement in the global CMRglu and in symptoms may also have important implications for the current concept of ''neuronal plasticity'' and for the cells' reactivity in order to recover their metabolic function. (orig.)

  17. CT and MRI normal findings

    International Nuclear Information System (INIS)

    Moeller, T.B.; Reif, E.

    1998-01-01

    This book gives answers to questions frequently heard especially from trainees and doctors not specialising in the field of radiology: Is that a normal finding? How do I decide? What are the objective criteria? The information presented is three-fold. The normal findings of the usual CT and MRI examinations are shown with high-quality pictures serving as a reference, with inscribed important additional information on measures, angles and other criteria describing the normal conditions. These criteria are further explained and evaluated in accompanying texts which also teach the systematic approach for individual picture analysis, and include a check list of major aspects, as a didactic guide for learning. The book is primarily intended for students, radiographers, radiology trainees and doctors from other medical fields, but radiology specialists will also find useful details of help in special cases. (orig./CB) [de

  18. Performance of normal adults on Rey Auditory Learning Test: a pilot study Desempenho de indivíduos saudáveis no Rey Auditory Verbal Learning Test (RAVLT: estudo piloto

    Directory of Open Access Journals (Sweden)

    Leila Cardoso Teruya

    2009-06-01

    Full Text Available The present study aimed to assess the performance of healthy Brazilian adults on the Rey Auditory Verbal Learning Test (RAVLT, a test devised for assessing memory, and to investigate the influence of the variables age, sex and education on the performance obtained, and finally to suggest scores which may be adopted for assessing memory with this instrument. The performance of 130 individuals, subdivided into groups according to age and education, was assessed. Overall performance decreased with age. Schooling presented a strong and positive relationship with scores on all subitems analyzed except learning, for which no influence was found. Mean scores of subitems analyzed did not differ significantly between men and women, except for the delayed recall subitem. This manuscript describes RAVLT scores according to age and education. In summary, this is a pilot study that presents a profile of Brazilian adults on A1, A7, recognition and LOT subitem.O objetivo deste estudo foi avaliar o desempenho de adultos normais brasileiros no Rey Auditory Verbal Learning Test (RAVLT, um teste destinado à avaliação da memória, e investigar a influência das variáveis idade, sexo e escolaridade no desempenho obtido, além de sugerir escores que possam ser utilizados na avaliação da memória segundo este instrumento. Foi avaliado o desempenho de 130 indivíduos, subdivididos em grupos de acordo com a idade e escolaridade. O desempenho geral no teste diminuiu com o aumento da idade. A escolaridade apresentou relação forte e positiva com os escores em todos os subitens analisados, exceto no aprendizado, no qual não foi verificada influência. As médias dos escores dos subitens analisados não foram estatisticamente diferentes entre homens e mulheres, exceto no subitem recordação tardia. Descrevemos os escores no RAVLT de acordo com faixa etária e escolaridade neste manuscrito.

  19. Extreme learning machine: a new alternative for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters.

    Science.gov (United States)

    Liu, Zhijian; Li, Hao; Tang, Xindong; Zhang, Xinyu; Lin, Fan; Cheng, Kewei

    2016-01-01

    Heat collection rate and heat loss coefficient are crucial indicators for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, the direct determination requires complex detection devices and a series of standard experiments, wasting too much time and manpower. To address this problem, we previously used artificial neural networks and support vector machine to develop precise knowledge-based models for predicting the heat collection rates and heat loss coefficients of water-in-glass evacuated tube solar water heaters, setting the properties measured by "portable test instruments" as the independent variables. A robust software for determination was also developed. However, in previous results, the prediction accuracy of heat loss coefficients can still be improved compared to those of heat collection rates. Also, in practical applications, even a small reduction in root mean square errors (RMSEs) can sometimes significantly improve the evaluation and business processes. As a further study, in this short report, we show that using a novel and fast machine learning algorithm-extreme learning machine can generate better predicted results for heat loss coefficient, which reduces the average RMSEs to 0.67 in testing.

  20. Learning how to rate video-recorded therapy sessions: a practical guide for trainees and advanced clinicians.

    Science.gov (United States)

    McCullough, Leigh; Bhatia, Maneet; Ulvenes, Pal; Berggraf, Lene; Osborn, Kristin

    2011-06-01

    Watching and rating psychotherapy sessions is an important yet often overlooked component of psychotherapy training. This article provides a simple and straightforward guide for using one Website (www.ATOStrainer.com) that provides an automated training protocol for rating of psychotherapy sessions. By the end of the article, readers will be able to have the knowledge to go to the Website and begin using this training method as soon as they have a recorded session to view. This article presents, (a) an overview of the Achievement of Therapeutic Objectives Scale (ATOS; McCullough et al., 2003a), a research tool used to rate psychotherapy sessions; (b) a description of APA training tapes, available for purchase from APA Books, that have been rated and scored by ATOS trained clinicians and posted on the Website; (c) step-by-step procedures on how ratings can be done; (d) an introduction to www.ATOStrainer.com where ratings can be entered and compared with expert ratings; and (e) first-hand personal experiences of the authors using this training method and the benefits it affords both trainees and experienced therapists. This psychotherapy training Website has the potential to be a key resource tool for graduate students, researchers, and clinicians. Our long-range goal is to promote the growth of our understanding of psychotherapy and to improve the quality of psychotherapy provided for patients.

  1. Accelerating the rate of improvement in cystic fibrosis care: contributions and insights of the learning and leadership collaborative.

    Science.gov (United States)

    Godfrey, Marjorie M; Oliver, Brant J

    2014-04-01

    The Learning and Leadership Collaborative (LLC) supports cystic fibrosis (CF) centres' responses to the variation in CF outcomes in the USA. Between 2002 and 2013, the Cystic Fibrosis Foundation (CFF) designed, tested and modified the LLC to guide front line staff efforts in these efforts. This paper describes the CFF LLC evolution and essential elements that have facilitated increased improvement capability of CF centres and improved CF outcomes. CF centre improvement teams across the USA have participated in 11 LLCs of 12 months' duration since 2002. Based on the Dartmouth Microsystem Improvement Curriculum, the original LLC included face to face meetings, an email listserv, conference calls and completion of between learning session task books. The LLCs evolved over time to include internet based learning, an electronic repository of improvement resources and examples, change ideas driven by evidence based clinical practice guidelines, benchmarking site visits, an applied QI measurement curriculum and team coaching. Over 90% of the CF centres in the USA have participated in the LLCs and have increased their improvement capabilities. Ten essential elements were identified as contributors to the successful LLCs: LLC national leadership and coordination, local leadership, people with CF and families involvement, registry data transparency, standardised improvement curriculum with evidence based change ideas, internet resources with reminders, team coaching, regular progress reporting and tracking, benchmarking site visits and applied improvement measurement. The LLCs have contributed to improved medical and process outcomes over the past 10 years. Ten essential elements of the LLCs may benefit improvement efforts in other chronic care populations and health systems.

  2. Learning time-dependent noise to reduce logical errors: real time error rate estimation in quantum error correction

    Science.gov (United States)

    Huo, Ming-Xia; Li, Ying

    2017-12-01

    Quantum error correction is important to quantum information processing, which allows us to reliably process information encoded in quantum error correction codes. Efficient quantum error correction benefits from the knowledge of error rates. We propose a protocol for monitoring error rates in real time without interrupting the quantum error correction. Any adaptation of the quantum error correction code or its implementation circuit is not required. The protocol can be directly applied to the most advanced quantum error correction techniques, e.g. surface code. A Gaussian processes algorithm is used to estimate and predict error rates based on error correction data in the past. We find that using these estimated error rates, the probability of error correction failures can be significantly reduced by a factor increasing with the code distance.

  3. Heart rate modulation in stable coronary artery disease without clinical heart failure: What we have already learned from SIGNIFY?

    Directory of Open Access Journals (Sweden)

    Gian Piero Perna

    2016-12-01

    In conclusion, heart rate is a marker of risk but is not a risk factor and/or a target of therapy in patients with stable coronary artery disease and preserved ventricular systolic function. Standard doses of ivabradine are indicated for treatment of angina as an alternative or in addition to beta-blockers, but should not be administered in association with CYP3A4 inhibitors or heart rate-lowering calcium-channel blockers.

  4. Learning While Earning: The New Normal

    Science.gov (United States)

    Carnevale, Anthony P.; Smith, Nicole; Melton, Michelle; Price, Eric, W.

    2015-01-01

    For decades, the popular conception of a college student in this country has been the full-time residential financially dependent student who enrolls in a four-year college immediately after graduating from high school. That student has not been the norm at U.S. postsecondary institutions for more than 30 years. Such students exist but they are…

  5. Normalized modes at selected points without normalization

    Science.gov (United States)

    Kausel, Eduardo

    2018-04-01

    As every textbook on linear algebra demonstrates, the eigenvectors for the general eigenvalue problem | K - λM | = 0 involving two real, symmetric, positive definite matrices K , M satisfy some well-defined orthogonality conditions. Equally well-known is the fact that those eigenvectors can be normalized so that their modal mass μ =ϕT Mϕ is unity: it suffices to divide each unscaled mode by the square root of the modal mass. Thus, the normalization is the result of an explicit calculation applied to the modes after they were obtained by some means. However, we show herein that the normalized modes are not merely convenient forms of scaling, but that they are actually intrinsic properties of the pair of matrices K , M, that is, the matrices already "know" about normalization even before the modes have been obtained. This means that we can obtain individual components of the normalized modes directly from the eigenvalue problem, and without needing to obtain either all of the modes or for that matter, any one complete mode. These results are achieved by means of the residue theorem of operational calculus, a finding that is rather remarkable inasmuch as the residues themselves do not make use of any orthogonality conditions or normalization in the first place. It appears that this obscure property connecting the general eigenvalue problem of modal analysis with the residue theorem of operational calculus may have been overlooked up until now, but which has in turn interesting theoretical implications.Á

  6. A systematic review of the effect of dietary exposure that could be achieved through normal dietary intake on learning and performance of school-aged children of relevance to UK schools.

    Science.gov (United States)

    Ells, Louisa J; Hillier, Frances C; Shucksmith, Janet; Crawley, Helen; Harbige, Laurence; Shield, Julian; Wiggins, Andy; Summerbell, Carolyn D

    2008-11-01

    The aim of the present review was to perform a systematic in-depth review of the best evidence from controlled trial studies that have investigated the effects of nutrition, diet and dietary change on learning, education and performance in school-aged children (4-18 years) from the UK and other developed countries. The twenty-nine studies identified for the review examined the effects of breakfast consumption, sugar intake, fish oil and vitamin supplementation and 'good diets'. In summary, the studies included in the present review suggest there is insufficient evidence to identify any effect of nutrition, diet and dietary change on learning, education or performance of school-aged children from the developed world. However, there is emerging evidence for the effects of certain fatty acids which appear to be a function of dose and time. Further research is required in settings of relevance to the UK and must be of high quality, representative of all populations, undertaken for longer durations and use universal validated measures of educational attainment. However, challenges in terms of interpreting the results of such studies within the context of factors such as family and community context, poverty, disease and the rate of individual maturation and neurodevelopment will remain. Whilst the importance of diet in educational attainment remains under investigation, the evidence for promotion of lower-fat, -salt and -sugar diets, high in fruits, vegetables and complex carbohydrates, as well as promotion of physical activity remains unequivocal in terms of health outcomes for all schoolchildren.

  7. An Extension to the Constructivist Coding Hypothesis as a Learning Model for Selective Feedback when the Base Rate Is High

    Science.gov (United States)

    Ghaffarzadegan, Navid; Stewart, Thomas R.

    2011-01-01

    Elwin, Juslin, Olsson, and Enkvist (2007) and Henriksson, Elwin, and Juslin (2010) offered the constructivist coding hypothesis to describe how people code the outcomes of their decisions when availability of feedback is conditional on the decision. They provided empirical evidence only for the 0.5 base rate condition. This commentary argues that…

  8. How Does Mozart's Music Affect Children's Reading? The Evidence from Learning Anxiety and Reading Rates with E-Books

    Science.gov (United States)

    Su, Yen-Ning; Kao, Chih-Chien; Hsu, Chia-Cheng; Pan, Lu-Chun; Cheng, Shu-Chen; Huang, Yueh-Min

    2017-01-01

    Some music has been proved effectively to mitigate anxiety, beneficial to reading. However, little was known on its influence of reading behaviors and outcomes. Thanks to the advance of e-book technology, it becomes possible to track reading rate and outcomes in a real-time manner by the underlying mobile devices. This study intends to examine the…

  9. Specific learning disorder: prevalence and gender differences.

    Directory of Open Access Journals (Sweden)

    Kristina Moll

    Full Text Available Comprehensive models of learning disorders have to consider both isolated learning disorders that affect one learning domain only, as well as comorbidity between learning disorders. However, empirical evidence on comorbidity rates including all three learning disorders as defined by DSM-5 (deficits in reading, writing, and mathematics is scarce. The current study assessed prevalence rates and gender ratios for isolated as well as comorbid learning disorders in a representative sample of 1633 German speaking children in 3rd and 4th Grade. Prevalence rates were analysed for isolated as well as combined learning disorders and for different deficit criteria, including a criterion for normal performance. Comorbid learning disorders occurred as frequently as isolated learning disorders, even when stricter cutoff criteria were applied. The relative proportion of isolated and combined disorders did not change when including a criterion for normal performance. Reading and spelling deficits differed with respect to their association with arithmetic problems: Deficits in arithmetic co-occurred more often with deficits in spelling than with deficits in reading. In addition, comorbidity rates for arithmetic and reading decreased when applying stricter deficit criteria, but stayed high for arithmetic and spelling irrespective of the chosen deficit criterion. These findings suggest that the processes underlying the relationship between arithmetic and reading might differ from those underlying the relationship between arithmetic and spelling. With respect to gender ratios, more boys than girls showed spelling deficits, while more girls were impaired in arithmetic. No gender differences were observed for isolated reading problems and for the combination of all three learning disorders. Implications of these findings for assessment and intervention of learning disorders are discussed.

  10. Room-temperature and temperature-dependent QSRR modelling for predicting the nitrate radical reaction rate constants of organic chemicals using ensemble learning methods.

    Science.gov (United States)

    Gupta, S; Basant, N; Mohan, D; Singh, K P

    2016-07-01

    Experimental determinations of the rate constants of the reaction of NO3 with a large number of organic chemicals are tedious, and time and resource intensive; and the development of computational methods has widely been advocated. In this study, we have developed room-temperature (298 K) and temperature-dependent quantitative structure-reactivity relationship (QSRR) models based on the ensemble learning approaches (decision tree forest (DTF) and decision treeboost (DTB)) for predicting the rate constant of the reaction of NO3 radicals with diverse organic chemicals, under OECD guidelines. Predictive powers of the developed models were established in terms of statistical coefficients. In the test phase, the QSRR models yielded a correlation (r(2)) of >0.94 between experimental and predicted rate constants. The applicability domains of the constructed models were determined. An attempt has been made to provide the mechanistic interpretation of the selected features for QSRR development. The proposed QSRR models outperformed the previous reports, and the temperature-dependent models offered a much wider applicability domain. This is the first report presenting a temperature-dependent QSRR model for predicting the nitrate radical reaction rate constant at different temperatures. The proposed models can be useful tools in predicting the reactivities of chemicals towards NO3 radicals in the atmosphere, hence, their persistence and exposure risk assessment.

  11. Normal foot and ankle

    International Nuclear Information System (INIS)

    Weissman, S.D.

    1989-01-01

    The foot may be thought of as a bag of bones tied tightly together and functioning as a unit. The bones re expected to maintain their alignment without causing symptomatology to the patient. The author discusses a normal radiograph. The bones must have normal shape and normal alignment. The density of the soft tissues should be normal and there should be no fractures, tumors, or foreign bodies

  12. Determination of the asymptotic normalization coefficients for C-14 + n - C-15,the C-14(n,gamma)C-15 reaction rate, and evaluation of a new method to determine spectroscopic factors

    Czech Academy of Sciences Publication Activity Database

    McCleskey, M.; Mukhamedzhanov, A. M.; Trache, L.; Tribble, R. E.; Banu, A.; Eremenko, V.; Goldberg, V. Z.; Lui, Y. W.; McCleskey, E.; Roeder, B. T.; Spiridon, A.; Carstoiu, F.; Burjan, Václav; Hons, Zdeněk; Thompson, I. J.

    2014-01-01

    Roč. 89, č. 4 (2014), 044605 ISSN 0556-2813 R&D Projects: GA MŠk(CZ) LH11001 Institutional support: RVO:61389005 Keywords : capture reactions * cross-section * asymptotic normalization coefficient Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.733, year: 2014

  13. 未来学习空间应用效果评价--以北京师范大学未来学习体验中心为例%Evaluation of the Future Learning Space:A Case Analysis of the Future Experiential Learning Center at Beijing Normal University

    Institute of Scientific and Technical Information of China (English)

    宋畅; 刘月; 陈悦; 李秋菊; 江丰光

    2015-01-01

    Research on active learning spaces has attracted great attention in recent years. A focus of the research is the design and use of these spaces that provide diverse and comfortable learning experiences. In 2014, the Future Ex-periential Learning Center at Beijing Normal University which contained eight classrooms with different functions was opened. They are interactive discussion classroom, interactive teaching classroom, interactive group-learning class-room, teacher education-training classroom, international cooperation remote classroom, mobile learning classroom, explore learning classroom, and recording and broadcasting control room. Twenty-one classes were taught in the Fu-ture Experiential Learning Center with eighteen teachers and more than 300 students involved. This study employed a combination of quantitative and qualitative methods to systematically evaluate the design and effects of the active learn-ing space at the Future Experiential Learning Center. We used questionnaires, interviews, and classroom observations to obtain data about student and teacher satisfaction and classroom interaction. Student satisfaction survey involved all the students. Questionnaires were sent to 215 students and 180 questionnaires were ultimate recovered. Teacher satis-faction survey was a sampling survey. Interviews were conducted with four typical teachers among all the eighteen teachers. Classroom observations were carried out in four typical classes which were chosen from all the twenty-one classes. The study found that students and teachers were overall satisfied with the classroom and believed the Future Learning Space could better support teaching. Firstly, the questionnaires showed that the mean value of the student satisfaction was 3. 90 (M=3. 90) which indicated the students were satisfied with the classroom generally. In all eight dimensions, there were five dimensions of which mean values were higher than the overall average (M=3. 90). They were classroom

  14. Lessons learned: the effect of increased production rate on operation and maintenance of OPG's Western Used Fuel Dry Storage Facility

    International Nuclear Information System (INIS)

    Morton, L.; Smith, N.

    2011-01-01

    In 2010, the Western Used Fuel Dry Storage Facility (WUFDSF) located at Ontario Power Generation's (OPG's) Western Waste Management Facility in Tiverton, ON, transferred, processed and stored a record-high number of Dry Storage Containers (DSC's) from Bruce Power's nuclear generating stations. The WUFDSF has been in operation since 2002. The facility transfers, processes, and stores the used fuel from the Bruce Power generating stations located in Tiverton, Ontario. As per a contractual agreement between OPG and Bruce Power, an annual DSC production and transfer schedule is agreed to between the two parties. In 2010, an increased annual production rate of 130 DSC's was agreed to between OPG and Bruce Power. Throughout 2007, 2008 and 2009, several facility modifications had been completed in anticipation of the increased production rate. These modifications included: Installation and commissioning of a second set of welding consoles; Addition of a second vacuum drying system; Procurement of a second transfer vehicle; and, Installation of a bulk gas system for welding cover gas. In 2010, the increased production rate of 130 DSC's/year came into effect. Throughout 2010, significant lessons learned were gained related to the impact of such a high production rate on the operation and maintenance of the facility. This paper presents the challenges and successes of that operation. The facility successfully achieved its production target with no safety incidents. This high rate of production is planned to continue for several years at the facility. Some challenges continue and these are being assessed and incorporated into the facility's business plan. In order to continue being successful, the facility must look to the future for opportunities for improvement and efficiencies to be gained. (author)

  15. Lessons learned: the effect of increased production rate on operation and maintenance of OPG's Western Used Fuel Dry Storage Facility

    Energy Technology Data Exchange (ETDEWEB)

    Morton, L.; Smith, N. [Ontario Power Generation, Tiverton, ON (Canada)

    2011-07-01

    In 2010, the Western Used Fuel Dry Storage Facility (WUFDSF) located at Ontario Power Generation's (OPG's) Western Waste Management Facility in Tiverton, ON, transferred, processed and stored a record-high number of Dry Storage Containers (DSC's) from Bruce Power's nuclear generating stations. The WUFDSF has been in operation since 2002. The facility transfers, processes, and stores the used fuel from the Bruce Power generating stations located in Tiverton, Ontario. As per a contractual agreement between OPG and Bruce Power, an annual DSC production and transfer schedule is agreed to between the two parties. In 2010, an increased annual production rate of 130 DSC's was agreed to between OPG and Bruce Power. Throughout 2007, 2008 and 2009, several facility modifications had been completed in anticipation of the increased production rate. These modifications included: Installation and commissioning of a second set of welding consoles; Addition of a second vacuum drying system; Procurement of a second transfer vehicle; and, Installation of a bulk gas system for welding cover gas. In 2010, the increased production rate of 130 DSC's/year came into effect. Throughout 2010, significant lessons learned were gained related to the impact of such a high production rate on the operation and maintenance of the facility. This paper presents the challenges and successes of that operation. The facility successfully achieved its production target with no safety incidents. This high rate of production is planned to continue for several years at the facility. Some challenges continue and these are being assessed and incorporated into the facility's business plan. In order to continue being successful, the facility must look to the future for opportunities for improvement and efficiencies to be gained. (author)

  16. Explorations in Statistics: The Analysis of Ratios and Normalized Data

    Science.gov (United States)

    Curran-Everett, Douglas

    2013-01-01

    Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This ninth installment of "Explorations in Statistics" explores the analysis of ratios and normalized--or standardized--data. As researchers, we compute a ratio--a numerator divided by a denominator--to compute a…

  17. Development of Chemistry Triangle Oriented Module on Topic of Reaction Rate for Senior High School Level Grade XI Chemistry Learning.

    Science.gov (United States)

    Sari, D. R.; Hardeli; Bayharti

    2018-04-01

    This study aims to produce chemistry triangle oriented module on topic of reaction rate, and to reveal the validity and practicality level of the generated module. The type of research used is EducationalDesign Research (EDR) with development model is Plompmodel. This model consists of three phases, which are preliminary research, prototyping phase, and assessment phase. The instrument used in this research is questionnaire validity and practicality. The data of the research were analyzed by using Kappa Cohen formula. The chemistry triangle oriented module validation sheet was given to 5 validators consisting of 3 chemistry lecturers and 2 high school chemistry teachers, while the practicality sheet was given to 2 chemistry teachers, 6 students of SMAN 10 Padang grade XII MIA 5 on the small groupevaluation and 25 students of SMAN 10 Padang grade XII MIA 6 on the field test. Based on the questionnaire validity analysis, the validity level of the module is very high with the value of kappa moment 0.87. The level of practicality based on teacher questionnaire response is very high category with a kappa moment value 0.96. Based on the questionnaire of student responses on small group evaluation, the level of practicality is very high category with a kappa moment 0.81, and the practicality is very high category with kappa moment value 0.83 based on questionnaire of student response on field test.

  18. Exciting Normal Distribution

    Science.gov (United States)

    Fuchs, Karl Josef; Simonovits, Reinhard; Thaller, Bernd

    2008-01-01

    This paper describes a high school project where the mathematics teaching and learning software M@th Desktop (MD) based on the Computer Algebra System Mathematica was used for symbolical and numerical calculations and for visualisation. The mathematics teaching and learning software M@th Desktop 2.0 (MD) contains the modules Basics including tools…

  19. Experiments on the learning ability of rats after a low dose-rate γ-irradation at various days of gestation

    International Nuclear Information System (INIS)

    Seitz, B.

    1986-01-01

    Pregnant Wistar rats were irradiated at days 11, 13 or 16 of gestation with 0.60 Gy of 60 Co-gamma-radiation at a dose-rate of 0.01 Gy/min. Controls were sham-irradiated and tested simultaneously. The adult female offspring was confronted with a set of standardized operant conditioning test sessions. Food reinforcement was made contingent to the fulfillment of gradually increased learning demand. The tests were micro-computer-controlled and the data stored on flexibe disks. Performance deficits were found in the groups (N=10) irradiated at gestational days 11 or 16 with respect to the controls. The pattern of operant test performance showed a circadian rhythm in all groups but was unaffected by irradiation. The observed performance differences between groups irradiated with the same dose but different dose-rate did not reach statistical significant levels. Motor coordination and strength were also tested in juvenile male littermates. In these tests the prenatally irradiated animals performed significantly poorer than the controls. (orig./MG) [de

  20. Diagnosis of major depressive disorder by combining multimodal information from heart rate dynamics and serum proteomics using machine-learning algorithm.

    Science.gov (United States)

    Kim, Eun Young; Lee, Min Young; Kim, Se Hyun; Ha, Kyooseob; Kim, Kwang Pyo; Ahn, Yong Min

    2017-06-02

    Major depressive disorder (MDD) is a systemic and multifactorial disorder that involves abnormalities in multiple biochemical pathways and the autonomic nervous system. This study applied a machine-learning method to classify MDD and control groups by incorporating data from serum proteomic analysis and heart rate variability (HRV) analysis for the identification of novel peripheral biomarkers. The study subjects consisted of 25 drug-free female MDD patients and 25 age- and sex-matched healthy controls. First, quantitative serum proteome profiles were analyzed by liquid chromatography-tandem mass spectrometry using pooled serum samples from 10 patients and 10 controls. Next, candidate proteins were quantified with multiple reaction monitoring (MRM) in 50 subjects. We also analyzed 22 linear and nonlinear HRV parameters in 50 subjects. Finally, we identified a combined biomarker panel consisting of proteins and HRV indexes using a support vector machine with recursive feature elimination. A separation between MDD and control groups was achieved using five parameters (apolipoprotein B, group-specific component, ceruloplasmin, RMSSD, and SampEn) at 80.1% classification accuracy. A combination of HRV and proteomic data achieved better classification accuracy. A high classification accuracy can be achieved by combining multimodal information from heart rate dynamics and serum proteomics in MDD. Our approach can be helpful for accurate clinical diagnosis of MDD. Further studies using larger, independent cohorts are needed to verify the role of these candidate biomarkers for MDD diagnosis. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Baby Poop: What's Normal?

    Science.gov (United States)

    ... I'm breast-feeding my newborn and her bowel movements are yellow and mushy. Is this normal for baby poop? Answers from Jay L. Hoecker, M.D. Yellow, mushy bowel movements are perfectly normal for breast-fed babies. Still, ...

  2. Visual Memories Bypass Normalization.

    Science.gov (United States)

    Bloem, Ilona M; Watanabe, Yurika L; Kibbe, Melissa M; Ling, Sam

    2018-05-01

    How distinct are visual memory representations from visual perception? Although evidence suggests that briefly remembered stimuli are represented within early visual cortices, the degree to which these memory traces resemble true visual representations remains something of a mystery. Here, we tested whether both visual memory and perception succumb to a seemingly ubiquitous neural computation: normalization. Observers were asked to remember the contrast of visual stimuli, which were pitted against each other to promote normalization either in perception or in visual memory. Our results revealed robust normalization between visual representations in perception, yet no signature of normalization occurring between working memory stores-neither between representations in memory nor between memory representations and visual inputs. These results provide unique insight into the nature of visual memory representations, illustrating that visual memory representations follow a different set of computational rules, bypassing normalization, a canonical visual computation.

  3. Making nuclear 'normal'

    International Nuclear Information System (INIS)

    Haehlen, Peter; Elmiger, Bruno

    2000-01-01

    The mechanics of the Swiss NPPs' 'come and see' programme 1995-1999 were illustrated in our contributions to all PIME workshops since 1996. Now, after four annual 'waves', all the country has been covered by the NPPs' invitation to dialogue. This makes PIME 2000 the right time to shed some light on one particular objective of this initiative: making nuclear 'normal'. The principal aim of the 'come and see' programme, namely to give the Swiss NPPs 'a voice of their own' by the end of the nuclear moratorium 1990-2000, has clearly been attained and was commented on during earlier PIMEs. It is, however, equally important that Swiss nuclear energy not only made progress in terms of public 'presence', but also in terms of being perceived as a normal part of industry, as a normal branch of the economy. The message that Swiss nuclear energy is nothing but a normal business involving normal people, was stressed by several components of the multi-prong campaign: - The speakers in the TV ads were real - 'normal' - visitors' guides and not actors; - The testimonials in the print ads were all real NPP visitors - 'normal' people - and not models; - The mailings inviting a very large number of associations to 'come and see' activated a typical channel of 'normal' Swiss social life; - Spending money on ads (a new activity for Swiss NPPs) appears to have resulted in being perceived by the media as a normal branch of the economy. Today we feel that the 'normality' message has well been received by the media. In the controversy dealing with antinuclear arguments brought forward by environmental organisations journalists nowadays as a rule give nuclear energy a voice - a normal right to be heard. As in a 'normal' controversy, the media again actively ask themselves questions about specific antinuclear claims, much more than before 1990 when the moratorium started. The result is that in many cases such arguments are discarded by journalists, because they are, e.g., found to be

  4. Normal Pressure Hydrocephalus

    Science.gov (United States)

    ... improves the chance of a good recovery. Without treatment, symptoms may worsen and cause death. What research is being done? The NINDS conducts and supports research on neurological disorders, including normal pressure hydrocephalus. Research on disorders such ...

  5. Normality in Analytical Psychology

    Science.gov (United States)

    Myers, Steve

    2013-01-01

    Although C.G. Jung’s interest in normality wavered throughout his career, it was one of the areas he identified in later life as worthy of further research. He began his career using a definition of normality which would have been the target of Foucault’s criticism, had Foucault chosen to review Jung’s work. However, Jung then evolved his thinking to a standpoint that was more aligned to Foucault’s own. Thereafter, the post Jungian concept of normality has remained relatively undeveloped by comparison with psychoanalysis and mainstream psychology. Jung’s disjecta membra on the subject suggest that, in contemporary analytical psychology, too much focus is placed on the process of individuation to the neglect of applications that consider collective processes. Also, there is potential for useful research and development into the nature of conflict between individuals and societies, and how normal people typically develop in relation to the spectrum between individuation and collectivity. PMID:25379262

  6. Normal pressure hydrocephalus

    Science.gov (United States)

    Hydrocephalus - occult; Hydrocephalus - idiopathic; Hydrocephalus - adult; Hydrocephalus - communicating; Dementia - hydrocephalus; NPH ... Ferri FF. Normal pressure hydrocephalus. In: Ferri FF, ed. ... Elsevier; 2016:chap 648. Rosenberg GA. Brain edema and disorders ...

  7. Normal Functioning Family

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Family Life Medical Home Family Dynamics Adoption & Foster Care ... Español Text Size Email Print Share Normal Functioning Family Page Content Article Body Is there any way ...

  8. Normal growth and development

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002456.htm Normal growth and development To use the sharing features on this page, please enable JavaScript. A child's growth and development can be divided into four periods: ...

  9. Late Quaternary Normal Faulting and Hanging Wall Basin Evolution of the Southwestern Rift Margin from Gravity and Geology, B.C.S., MX and Exploring the Influence of Text-Figure Format on Introductory Geology Learning

    Science.gov (United States)

    Busch, Melanie M. D.

    2011-01-01

    An array of north-striking, left-stepping, active normal faults is situated along the southwestern margin of the Gulf of California. This normal fault system is the marginal fault system of the oblique-divergent plate boundary within the Gulf of California. To better understand the role of upper-crustal processes during development of an obliquely…

  10. Non-Contact Heart Rate and Blood Pressure Estimations from Video Analysis and Machine Learning Modelling Applied to Food Sensory Responses: A Case Study for Chocolate.

    Science.gov (United States)

    Gonzalez Viejo, Claudia; Fuentes, Sigfredo; Torrico, Damir D; Dunshea, Frank R

    2018-06-03

    Traditional methods to assess heart rate (HR) and blood pressure (BP) are intrusive and can affect results in sensory analysis of food as participants are aware of the sensors. This paper aims to validate a non-contact method to measure HR using the photoplethysmography (PPG) technique and to develop models to predict the real HR and BP based on raw video analysis (RVA) with an example application in chocolate consumption using machine learning (ML). The RVA used a computer vision algorithm based on luminosity changes on the different RGB color channels using three face-regions (forehead and both cheeks). To validate the proposed method and ML models, a home oscillometric monitor and a finger sensor were used. Results showed high correlations with the G color channel (R² = 0.83). Two ML models were developed using three face-regions: (i) Model 1 to predict HR and BP using the RVA outputs with R = 0.85 and (ii) Model 2 based on time-series prediction with HR, magnitude and luminosity from RVA inputs to HR values every second with R = 0.97. An application for the sensory analysis of chocolate showed significant correlations between changes in HR and BP with chocolate hardness and purchase intention.

  11. Smooth quantile normalization.

    Science.gov (United States)

    Hicks, Stephanie C; Okrah, Kwame; Paulson, Joseph N; Quackenbush, John; Irizarry, Rafael A; Bravo, Héctor Corrada

    2018-04-01

    Between-sample normalization is a critical step in genomic data analysis to remove systematic bias and unwanted technical variation in high-throughput data. Global normalization methods are based on the assumption that observed variability in global properties is due to technical reasons and are unrelated to the biology of interest. For example, some methods correct for differences in sequencing read counts by scaling features to have similar median values across samples, but these fail to reduce other forms of unwanted technical variation. Methods such as quantile normalization transform the statistical distributions across samples to be the same and assume global differences in the distribution are induced by only technical variation. However, it remains unclear how to proceed with normalization if these assumptions are violated, for example, if there are global differences in the statistical distributions between biological conditions or groups, and external information, such as negative or control features, is not available. Here, we introduce a generalization of quantile normalization, referred to as smooth quantile normalization (qsmooth), which is based on the assumption that the statistical distribution of each sample should be the same (or have the same distributional shape) within biological groups or conditions, but allowing that they may differ between groups. We illustrate the advantages of our method on several high-throughput datasets with global differences in distributions corresponding to different biological conditions. We also perform a Monte Carlo simulation study to illustrate the bias-variance tradeoff and root mean squared error of qsmooth compared to other global normalization methods. A software implementation is available from https://github.com/stephaniehicks/qsmooth.

  12. Monitoring the normal body

    DEFF Research Database (Denmark)

    Nissen, Nina Konstantin; Holm, Lotte; Baarts, Charlotte

    2015-01-01

    of practices for monitoring their bodies based on different kinds of calculations of weight and body size, observations of body shape, and measurements of bodily firmness. Biometric measurements are familiar to them as are health authorities' recommendations. Despite not belonging to an extreme BMI category...... provides us with knowledge about how to prevent future overweight or obesity. This paper investigates body size ideals and monitoring practices among normal-weight and moderately overweight people. Methods : The study is based on in-depth interviews combined with observations. 24 participants were...... recruited by strategic sampling based on self-reported BMI 18.5-29.9 kg/m2 and socio-demographic factors. Inductive analysis was conducted. Results : Normal-weight and moderately overweight people have clear ideals for their body size. Despite being normal weight or close to this, they construct a variety...

  13. Normal modified stable processes

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole Eiler; Shephard, N.

    2002-01-01

    Gaussian (NGIG) laws. The wider framework thus established provides, in particular, for added flexibility in the modelling of the dynamics of financial time series, of importance especially as regards OU based stochastic volatility models for equities. In the special case of the tempered stable OU process......This paper discusses two classes of distributions, and stochastic processes derived from them: modified stable (MS) laws and normal modified stable (NMS) laws. This extends corresponding results for the generalised inverse Gaussian (GIG) and generalised hyperbolic (GH) or normal generalised inverse...

  14. Normalization of satellite imagery

    Science.gov (United States)

    Kim, Hongsuk H.; Elman, Gregory C.

    1990-01-01

    Sets of Thematic Mapper (TM) imagery taken over the Washington, DC metropolitan area during the months of November, March and May were converted into a form of ground reflectance imagery. This conversion was accomplished by adjusting the incident sunlight and view angles and by applying a pixel-by-pixel correction for atmospheric effects. Seasonal color changes of the area can be better observed when such normalization is applied to space imagery taken in time series. In normalized imagery, the grey scale depicts variations in surface reflectance and tonal signature of multi-band color imagery can be directly interpreted for quantitative information of the target.

  15. The normal holonomy group

    International Nuclear Information System (INIS)

    Olmos, C.

    1990-05-01

    The restricted holonomy group of a Riemannian manifold is a compact Lie group and its representation on the tangent space is a product of irreducible representations and a trivial one. Each one of the non-trivial factors is either an orthogonal representation of a connected compact Lie group which acts transitively on the unit sphere or it is the isotropy representation of a single Riemannian symmetric space of rank ≥ 2. We prove that, all these properties are also true for the representation on the normal space of the restricted normal holonomy group of any submanifold of a space of constant curvature. 4 refs

  16. Normality in Analytical Psychology

    Directory of Open Access Journals (Sweden)

    Steve Myers

    2013-11-01

    Full Text Available Although C.G. Jung’s interest in normality wavered throughout his career, it was one of the areas he identified in later life as worthy of further research. He began his career using a definition of normality which would have been the target of Foucault’s criticism, had Foucault chosen to review Jung’s work. However, Jung then evolved his thinking to a standpoint that was more aligned to Foucault’s own. Thereafter, the post Jungian concept of normality has remained relatively undeveloped by comparison with psychoanalysis and mainstream psychology. Jung’s disjecta membra on the subject suggest that, in contemporary analytical psychology, too much focus is placed on the process of individuation to the neglect of applications that consider collective processes. Also, there is potential for useful research and development into the nature of conflict between individuals and societies, and how normal people typically develop in relation to the spectrum between individuation and collectivity.

  17. Medically-enhanced normality

    DEFF Research Database (Denmark)

    Møldrup, Claus; Traulsen, Janine Morgall; Almarsdóttir, Anna Birna

    2003-01-01

    Objective: To consider public perspectives on the use of medicines for non-medical purposes, a usage called medically-enhanced normality (MEN). Method: Examples from the literature were combined with empirical data derived from two Danish research projects: a Delphi internet study and a Telebus...

  18. Operant learning and differential-reinforcement-of-low-rate 36-s responding in 5-HT1A and 5-HT1B receptor knockout mice.

    NARCIS (Netherlands)

    Pattij, T.; Broersen, L.M.; Linde, J. van der; Groenink, L.; Gugten, J. van der; Maes, R.A.A.; Olivier, B.

    2003-01-01

    Previous studies with mice lacking 5-HT(1A) (1AKO) and 5-HT(1B) (1BKO) receptors in hippocampus-dependent learning and memory paradigms, suggest that these receptors play an important role in learning and memory, although their precise role is unclear. In the present study, 1AKO and 1BKO mice were

  19. Assessing the Success Rate of Students Using a Learning Management System Together with a Collaborative Tool in Web-Based Teaching of Programming Languages

    Science.gov (United States)

    Cavus, Nadire; Ibrahim, Dogan

    2007-01-01

    The development of collaborative studies in learning has led to a renewed interest in the field of Web-based education. In this experimental study a highly interactive and collaborative virtual teaching environment has been created by supporting Moodle LMS with collaborative learning tool GREWPtool. The aim of this experimental study has been to…

  20. Underserved Students Who Earn Credit through Prior Learning Assessment (PLA) Have Higher Degree Completion Rates and Shorter Time-to-Degree. Research Brief

    Science.gov (United States)

    Klein-Collins, Rebecca

    2011-01-01

    In 2010, the Council for Adult and Experiential Learning (CAEL) released a report on a multi-institutional study on prior learning assessment (PLA) and adult student outcomes. The study examined data from 62,475 adult students at 48 colleges and universities, following the students' academic progress over the course of seven years. The data from…

  1. Comet Giacobini-Zinner - a normal comet?

    International Nuclear Information System (INIS)

    Cochran, A.L.; Barker, E.S.

    1987-01-01

    Observations of Comet Giacobini-Zinner were obtained during its 1985 apparition using an IDS spectrograph at McDonald Observatory. Column densities and production rates were computed. The production rates were compared to observations of other normal comets. Giacobini-Zinner is shown to be depleted in C2 and C3 relative to CN. These production rates are down by a factor of 5. 12 references

  2. Idiopathic Normal Pressure Hydrocephalus

    Directory of Open Access Journals (Sweden)

    Basant R. Nassar BS

    2016-04-01

    Full Text Available Idiopathic normal pressure hydrocephalus (iNPH is a potentially reversible neurodegenerative disease commonly characterized by a triad of dementia, gait, and urinary disturbance. Advancements in diagnosis and treatment have aided in properly identifying and improving symptoms in patients. However, a large proportion of iNPH patients remain either undiagnosed or misdiagnosed. Using PubMed search engine of keywords “normal pressure hydrocephalus,” “diagnosis,” “shunt treatment,” “biomarkers,” “gait disturbances,” “cognitive function,” “neuropsychology,” “imaging,” and “pathogenesis,” articles were obtained for this review. The majority of the articles were retrieved from the past 10 years. The purpose of this review article is to aid general practitioners in further understanding current findings on the pathogenesis, diagnosis, and treatment of iNPH.

  3. Normal Weight Dyslipidemia

    DEFF Research Database (Denmark)

    Ipsen, David Hojland; Tveden-Nyborg, Pernille; Lykkesfeldt, Jens

    2016-01-01

    Objective: The liver coordinates lipid metabolism and may play a vital role in the development of dyslipidemia, even in the absence of obesity. Normal weight dyslipidemia (NWD) and patients with nonalcoholic fatty liver disease (NAFLD) who do not have obesity constitute a unique subset...... of individuals characterized by dyslipidemia and metabolic deterioration. This review examined the available literature on the role of the liver in dyslipidemia and the metabolic characteristics of patients with NAFLD who do not have obesity. Methods: PubMed was searched using the following keywords: nonobese......, dyslipidemia, NAFLD, NWD, liver, and metabolically obese/unhealthy normal weight. Additionally, article bibliographies were screened, and relevant citations were retrieved. Studies were excluded if they had not measured relevant biomarkers of dyslipidemia. Results: NWD and NAFLD without obesity share a similar...

  4. Dissolution rates of unirradiated UO{sub 2}, UO{sub 2} doped with {sup 233}U, and spent fuel under normal atmospheric conditions and under reducing conditions using an isotope dilution method

    Energy Technology Data Exchange (ETDEWEB)

    Ollila, Kaija [VTT Processes, Helsinki (Finland); Albinsson, Yngve [Chalmers Univ. of Technology, Goeteborg (Sweden); Oversby, Virginia [VMO Konsult, Stockholm (Sweden); Cowper, Mark [AEA Technology, Harwell (United Kingdom)

    2003-10-01

    The experimental results given in this report allow us to draw the following conclusions. 1) Tests using unirradiated fuel pellet materials from two different manufacturers gave very different dissolution rates under air atmosphere testing. Tests for fragments of pellets from different pellets made by the same manufacturer gave good agreement. This indicates that details of the manufacturing process have a large effect on the behavior of unirradiated UO{sub 2} in dissolution experiments. Care must be taken in interpreting differences in results obtained in different laboratories because the results may be affected by manufacturing effects. 2) Long-term tests under air atmosphere have begun to show the effects of precipitation. Further testing will be needed before the samples reach steady state. 3) Testing of unirradiated UO{sub 2} in systems containing an iron strip to produce reducing conditions gave [U] less than detection limits (<0.02 ppb) after a few days to a few weeks of testing. Uranium recovered from the rinsing of reaction vessels and from acid stripping of vessels was shown to be from dissolution of grains of solid dislodged when the samples were handled after the tests were terminated. 4) Batch tests conducted under reducing conditions showed evidence of colloidal material in the early solution samples. 5) In the batch tests, measurements taken at day 3 and day 5 show that precipitation occurs from day 3 to day 5 without any further dissolution of the solid. 6) At termination of the batch tests, all but one sample had [U] in solution less than detection limits (< 0.02 ppb). Materials recovered in test termination samples showed evidence for recovery of small amounts - amounts corresponding to that expected from a few grains of 5 to 10 {mu}m size - in the acidified solution samples. These are interpreted to have been dislodged during sample handling operations. 7) Batch test data show that increasing test duration beyond 2 weeks does not provide

  5. Ethics and "normal birth".

    Science.gov (United States)

    Lyerly, Anne Drapkin

    2012-12-01

    The concept of "normal birth" has been promoted as ideal by several international organizations, although debate about its meaning is ongoing. In this article, I examine the concept of normalcy to explore its ethical implications and raise a trio of concerns. First, in its emphasis on nonuse of technology as a goal, the concept of normalcy may marginalize women for whom medical intervention is necessary or beneficial. Second, in its emphasis on birth as a socially meaningful event, the mantra of normalcy may unintentionally avert attention to meaning in medically complicated births. Third, the emphasis on birth as a normal and healthy event may be a contributor to the long-standing tolerance for the dearth of evidence guiding the treatment of illness during pregnancy and the failure to responsibly and productively engage pregnant women in health research. Given these concerns, it is worth debating not just what "normal birth" means, but whether the term as an ideal earns its keep. © 2012, Copyright the Authors Journal compilation © 2012, Wiley Periodicals, Inc.

  6. AFP Algorithm and a Canonical Normal Form for Horn Formulas

    OpenAIRE

    Majdoddin, Ruhollah

    2014-01-01

    AFP Algorithm is a learning algorithm for Horn formulas. We show that it does not improve the complexity of AFP Algorithm, if after each negative counterexample more that just one refinements are performed. Moreover, a canonical normal form for Horn formulas is presented, and it is proved that the output formula of AFP Algorithm is in this normal form.

  7. Advancing Normal Birth: Organizations, Goals, and Research

    OpenAIRE

    Hotelling, Barbara A.; Humenick, Sharron S.

    2005-01-01

    In this column, the support for advancing normal birth is summarized, based on a comparison of the goals of Healthy People 2010, Lamaze International, the Coalition for Improving Maternity Services, and the midwifery model of care. Research abstracts are presented to provide evidence that the midwifery model of care safely and economically advances normal birth. Rates of intervention experienced, as reported in the Listening to Mothers survey, are compared to the forms of care recommended by ...

  8. Distinguishing hyperhidrosis and normal physiological sweat production

    DEFF Research Database (Denmark)

    Thorlacius, Linnea; Gyldenløve, Mette; Zachariae, Claus

    2015-01-01

    of this study was to establish reference intervals for normal physiological axillary and palmar sweat production. METHODS: Gravimetric testing was performed in 75 healthy control subjects. Subsequently, these results were compared with findings in a cohort of patients with hyperhidrosis and with the results...... 100 mg/5 min. CONCLUSIONS: A sweat production rate of 100 mg/5 min as measured by gravimetric testing may be a reasonable cut-off value for distinguishing axillary and palmar hyperhidrosis from normal physiological sweat production....

  9. Theory of normal metals

    International Nuclear Information System (INIS)

    Mahan, G.D.

    1992-01-01

    The organizers requested that I give eight lectures on the theory of normal metals, ''with an eye on superconductivity.'' My job was to cover the general properties of metals. The topics were selected according to what the students would need to known for the following lectures on superconductivity. My role was to prepare the ground work for the later lectures. The problem is that there is not yet a widely accepted theory for the mechanism which pairs the electrons. Many mechanisms have been proposed, with those of phonons and spin fluctuations having the most followers. So I tried to discuss both topics. I also introduced the tight-binding model for metals, which forms the basis for most of the work on the cuprate superconductors

  10. Quantitative thallium-201 myocardial exercise scintigraphy in normal subjects and patients with normal coronary arteries

    International Nuclear Information System (INIS)

    Niemeyer, M.G.; St. Antonius Hospital Nieuwegein; Laarman, G.J.; Lelbach, S.; Cramer, M.J.; Ascoop, C.A.P.L.; Verzijlbergen, J.F.; Wall, E.E. van der; Zwinderman, A.H.; Pauwels, E.K.J.

    1990-01-01

    Quantitative thallium-201 myocardial exercise scintigraphy was tested in two patient populations representing alternative standards for cardiac normality: group I comprised 18 male uncatherized patients with a low likelihood of coronary artery disease (CAD); group II contained 41 patients with normal coronary arteriograms. Group I patients were younger, they achieved a higher rate-pressure product than group II patients; all had normal findings by phisical examination and electrocardiography at rest and exercise. Group II patients comprised 21 females, 11 patients showed abnormal electrocardiography at rest, and five patients showed ischemic ST depression during exercise. Twelve patients had sign of minimal CAD. Twelve patients revealed abnormal visual and quantitative thallium findings, three of these patients had minimal CAD. Profiles of uptake and washout of thallium-201 were derived from both patient groups, and compared with normal limits developed by Maddahi et al. Furthermore, low likelihood and angiographically normal patients may differ substantially, and both sets of normal patients should be considered when establishing criteria of abnormality in exercise thallium imaging. When commercial software containing normal limits for quantitative analysis of exercise thallium-201 imaging is used in clinical practice, it is mandatory to compare these with normal limits of uptake and washout of thallium-201, derived from the less heterogeneous group of low-likelihood subjects, which should be used in selecting a normal population to define normality. (author). 37 refs.; 3 figs; 1 tab

  11. Creating a brief rating scale for the assessment of learning disabilities using reliability and true score estimates of the scale's items based on the Rasch model.

    Science.gov (United States)

    Sideridis, Georgios; Padeliadu, Susana

    2013-01-01

    The purpose of the present studies was to provide the means to create brief versions of instruments that can aid the diagnosis and classification of students with learning disabilities and comorbid disorders (e.g., attention-deficit/hyperactivity disorder). A sample of 1,108 students with and without a diagnosis of learning disabilities took part in study 1. Using information from modern theory methods (i.e., the Rasch model), a scale was created that included fewer than one third of the original battery items designed to assess reading skills. This best item synthesis was then evaluated for its predictive and criterion validity with a valid external reading battery (study 2). Using a sample of 232 students with and without learning disabilities, results indicated that the brief version of the scale was equally effective as the original scale in predicting reading achievement. Analysis of the content of the brief scale indicated that the best item synthesis involved items from cognition, motivation, strategy use, and advanced reading skills. It is suggested that multiple psychometric criteria be employed in evaluating the psychometric adequacy of scales used for the assessment and identification of learning disabilities and comorbid disorders.

  12. Strength of Gamma Rhythm Depends on Normalization

    Science.gov (United States)

    Ray, Supratim; Ni, Amy M.; Maunsell, John H. R.

    2013-01-01

    Neuronal assemblies often exhibit stimulus-induced rhythmic activity in the gamma range (30–80 Hz), whose magnitude depends on the attentional load. This has led to the suggestion that gamma rhythms form dynamic communication channels across cortical areas processing the features of behaviorally relevant stimuli. Recently, attention has been linked to a normalization mechanism, in which the response of a neuron is suppressed (normalized) by the overall activity of a large pool of neighboring neurons. In this model, attention increases the excitatory drive received by the neuron, which in turn also increases the strength of normalization, thereby changing the balance of excitation and inhibition. Recent studies have shown that gamma power also depends on such excitatory–inhibitory interactions. Could modulation in gamma power during an attention task be a reflection of the changes in the underlying excitation–inhibition interactions? By manipulating the normalization strength independent of attentional load in macaque monkeys, we show that gamma power increases with increasing normalization, even when the attentional load is fixed. Further, manipulations of attention that increase normalization increase gamma power, even when they decrease the firing rate. Thus, gamma rhythms could be a reflection of changes in the relative strengths of excitation and normalization rather than playing a functional role in communication or control. PMID:23393427

  13. Comparative ultrasound measurement of normal thyroid gland ...

    African Journals Online (AJOL)

    2011-08-31

    Aug 31, 2011 ... the normal thyroid gland has a homogenous increased medium level echo texture. The childhood thyroid gland dimension correlates linearly with age and body surface unlike adults. [14] Iodothyronine (T3) and thyroxine (T4) are thyroid hormones which function to control the basal metabolic rate (BMR).

  14. Normal modes of weak colloidal gels

    Science.gov (United States)

    Varga, Zsigmond; Swan, James W.

    2018-01-01

    The normal modes and relaxation rates of weak colloidal gels are investigated in calculations using different models of the hydrodynamic interactions between suspended particles. The relaxation spectrum is computed for freely draining, Rotne-Prager-Yamakawa, and accelerated Stokesian dynamics approximations of the hydrodynamic mobility in a normal mode analysis of a harmonic network representing several colloidal gels. We find that the density of states and spatial structure of the normal modes are fundamentally altered by long-ranged hydrodynamic coupling among the particles. Short-ranged coupling due to hydrodynamic lubrication affects only the relaxation rates of short-wavelength modes. Hydrodynamic models accounting for long-ranged coupling exhibit a microscopic relaxation rate for each normal mode, λ that scales as l-2, where l is the spatial correlation length of the normal mode. For the freely draining approximation, which neglects long-ranged coupling, the microscopic relaxation rate scales as l-γ, where γ varies between three and two with increasing particle volume fraction. A simple phenomenological model of the internal elastic response to normal mode fluctuations is developed, which shows that long-ranged hydrodynamic interactions play a central role in the viscoelasticity of the gel network. Dynamic simulations of hard spheres that gel in response to short-ranged depletion attractions are used to test the applicability of the density of states predictions. For particle concentrations up to 30% by volume, the power law decay of the relaxation modulus in simulations accounting for long-ranged hydrodynamic interactions agrees with predictions generated by the density of states of the corresponding harmonic networks as well as experimental measurements. For higher volume fractions, excluded volume interactions dominate the stress response, and the prediction from the harmonic network density of states fails. Analogous to the Zimm model in polymer

  15. Metacognition and Reading: Comparing Three Forms of Metacognition in Normally Developing Readers and Readers with Dyslexia.

    Science.gov (United States)

    Furnes, Bjarte; Norman, Elisabeth

    2015-08-01

    Metacognition refers to 'cognition about cognition' and includes metacognitive knowledge, strategies and experiences (Efklides, 2008; Flavell, 1979). Research on reading has shown that better readers demonstrate more metacognitive knowledge than poor readers (Baker & Beall, 2009), and that reading ability improves through strategy instruction (Gersten, Fuchs, Williams, & Baker, 2001). The current study is the first to specifically compare the three forms of metacognition in dyslexic (N = 22) versus normally developing readers (N = 22). Participants read two factual texts, with learning outcome measured by a memory task. Metacognitive knowledge and skills were assessed by self-report. Metacognitive experiences were measured by predictions of performance and judgments of learning. Individuals with dyslexia showed insight into their reading problems, but less general knowledge of how to approach text reading. They more often reported lack of available reading strategies, but groups did not differ in the use of deep and surface strategies. Learning outcome and mean ratings of predictions of performance and judgments of learning were lower in dyslexic readers, but not the accuracy with which metacognitive experiences predicted learning. Overall, the results indicate that dyslexic reading and spelling problems are not generally associated with lower levels of metacognitive knowledge, metacognitive strategies or sensitivity to metacognitive experiences in reading situations. 2015 The Authors. Dyslexia Published by John Wiley & Sons Ltd.

  16. Theoretical Foundations of Active Learning

    Science.gov (United States)

    2009-05-01

    I study the informational complexity of active learning in a statistical learning theory framework. Specifically, I derive bounds on the rates of...convergence achievable by active learning , under various noise models and under general conditions on the hypothesis class. I also study the theoretical...advantages of active learning over passive learning, and develop procedures for transforming passive learning algorithms into active learning algorithms

  17. Determination of the asymptotic normalization coefficients for 14C + n <--> 15C, the 14C(n, gamma)15C reaction rate, and evaluation of a new method to determine spectroscopic factors

    Energy Technology Data Exchange (ETDEWEB)

    McCleskey, M; Mukhamedzhanov, A M; Trache, L; Tribble, R E; Banu, A; Eremenko, V; Goldberg, V Z; Lui, Y W; McCleskey, E; Roeder, B T; Spiridon, A; Carstoiu, F; Burjan, V; Hons, Z; Thompson, I J

    2014-04-17

    The 14C + n <--> 15C system has been used as a test case in the evaluation of a new method to determine spectroscopic factors that uses the asymptotic normalization coefficient (ANC). The method proved to be unsuccessful for this case. As part of this experimental program, the ANCs for the 15C ground state and first excited state were determined using a heavy-ion neutron transfer reaction as well as the inverse kinematics (d,p) reaction, measured at the Texas A&M Cyclotron Institute. The ANCs were used to evaluate the astrophysical direct neutron capture rate on 14C, which was then compared with the most recent direct measurement and found to be in good agreement. A study of the 15C SF via its mirror nucleus 15F and a new insight into deuteron stripping theory are also presented.

  18. Barriers and facilitators to learning and performing cardiopulmonary resuscitation in neighborhoods with low bystander cardiopulmonary resuscitation prevalence and high rates of cardiac arrest in Columbus, OH.

    Science.gov (United States)

    Sasson, Comilla; Haukoos, Jason S; Bond, Cindy; Rabe, Marilyn; Colbert, Susan H; King, Renee; Sayre, Michael; Heisler, Michele

    2013-09-01

    Residents who live in neighborhoods that are primarily black, Latino, or poor are more likely to have an out-of-hospital cardiac arrest, less likely to receive cardiopulmonary resuscitation (CPR), and less likely to survive. No prior studies have been conducted to understand the contributing factors that may decrease the likelihood of residents learning and performing CPR in these neighborhoods. The goal of this study was to identify barriers and facilitators to learning and performing CPR in 3 low-income, high-risk, and predominantly black neighborhoods in Columbus, OH. Community-Based Participatory Research approaches were used to develop and conduct 6 focus groups in conjunction with community partners in 3 target high-risk neighborhoods in Columbus, OH, in January to February 2011. Snowball and purposeful sampling, done by community liaisons, was used to recruit participants. Three reviewers analyzed the data in an iterative process to identify recurrent and unifying themes. Three major barriers to learning CPR were identified and included financial, informational, and motivational factors. Four major barriers were identified for performing CPR and included fear of legal consequences, emotional issues, knowledge, and situational concerns. Participants suggested that family/self-preservation, emotional, and economic factors may serve as potential facilitators in increasing the provision of bystander CPR. The financial cost of CPR training, lack of information, and the fear of risking one's own life must be addressed when designing a community-based CPR educational program. Using data from the community can facilitate improved design and implementation of CPR programs.

  19. Short proofs of strong normalization

    OpenAIRE

    Wojdyga, Aleksander

    2008-01-01

    This paper presents simple, syntactic strong normalization proofs for the simply-typed lambda-calculus and the polymorphic lambda-calculus (system F) with the full set of logical connectives, and all the permutative reductions. The normalization proofs use translations of terms and types to systems, for which strong normalization property is known.

  20. Differential metabolic rates in prefrontal and temporal Brodmann areas in schizophrenia and schizotypal personality disorder.

    Science.gov (United States)

    Buchsbaum, Monte S; Nenadic, Igor; Hazlett, Erin A; Spiegel-Cohen, Jacqueline; Fleischman, Michael B; Akhavan, Arash; Silverman, Jeremy M; Siever, Larry J

    2002-03-01

    In an exploration of the schizophrenia spectrum, we compared cortical metabolic rates in unmedicated patients with schizophrenia and schizotypal personality disorder (SPD) with findings in age- and sex-matched normal volunteers. Coregistered magnetic resonance imaging (MRI) and positron emission tomography (PET) scans were obtained in 27 schizophrenic, 13 SPD, and 32 normal volunteers who performed a serial verbal learning test during tracer uptake. A template of Brodmann areas derived from a whole brain histological section atlas was used to analyze PET findings. Significantly lower metabolic rates were found in prefrontal areas 44-46 in schizophrenic patients than in normal volunteers. SPD patients did not differ from normal volunteers in most lateral frontal regions, but they had values intermediate between those of normal volunteers and schizophrenic patients in lateral temporal regions. SPD patients showed higher than normal metabolic rates in both medial frontal and medial temporal areas. Metabolic rates in Brodmann area 10 were distinctly higher in SPD patients than in either normal volunteers or schizophrenic patients.

  1. Barriers and Facilitators to Learning and Performing Cardiopulmonary Resuscitation (CPR) in Neighborhoods with Low Bystander CPR Prevalence and High Rates of Cardiac Arrest in Columbus, Ohio

    Science.gov (United States)

    Sasson, Comilla; Haukoos, Jason S.; Bond, Cindy; Rabe, Marilyn; Colbert, Susan H.; King, Renee; Sayre, Michael; Heisler, Michele

    2013-01-01

    Background Residents who live in neighborhoods that are primarily African-American, Latino, or poor are more likely to have an out-of-hospital cardiac arrest (OHCA), less likely to receive cardiopulmonary resuscitation (CPR), and less likely to survive. No prior studies have been conducted to understand the contributing factors that may decrease the likelihood of residents learning and performing CPR in these neighborhoods. The goal of this study was to identify barriers and facilitators to learning and performing CPR in three low-income, “high-risk” predominantly African American, neighborhoods in Columbus, Ohio. Methods and Results Community-Based Participatory Research (CBPR) approaches were used to develop and conduct six focus groups in conjunction with community partners in three target high-risk neighborhoods in Columbus, Ohio in January-February 2011. Snowball and purposeful sampling, done by community liaisons, was used to recruit participants. Three reviewers analyzed the data in an iterative process to identify recurrent and unifying themes. Three major barriers to learning CPR were identified and included financial, informational, and motivational factors. Four major barriers were identified for performing CPR and included fear of legal consequences, emotional issues, knowledge, and situational concerns. Participants suggested that family/self-preservation, emotional, and economic factors may serve as potential facilitators in increasing the provision of bystander CPR. Conclusion The financial cost of CPR training, lack of information, and the fear of risking one's own life must be addressed when designing a community-based CPR educational program. Using data from the community can facilitate improved design and implementation of CPR programs. PMID:24021699

  2. Seeing the Errors You Feel Enhances Locomotor Performance but Not Learning.

    Science.gov (United States)

    Roemmich, Ryan T; Long, Andrew W; Bastian, Amy J

    2016-10-24

    In human motor learning, it is thought that the more information we have about our errors, the faster we learn. Here, we show that additional error information can lead to improved motor performance without any concomitant improvement in learning. We studied split-belt treadmill walking that drives people to learn a new gait pattern using sensory prediction errors detected by proprioceptive feedback. When we also provided visual error feedback, participants acquired the new walking pattern far more rapidly and showed accelerated restoration of the normal walking pattern during washout. However, when the visual error feedback was removed during either learning or washout, errors reappeared with performance immediately returning to the level expected based on proprioceptive learning alone. These findings support a model with two mechanisms: a dual-rate adaptation process that learns invariantly from sensory prediction error detected by proprioception and a visual-feedback-dependent process that monitors learning and corrects residual errors but shows no learning itself. We show that our voluntary correction model accurately predicted behavior in multiple situations where visual feedback was used to change acquisition of new walking patterns while the underlying learning was unaffected. The computational and behavioral framework proposed here suggests that parallel learning and error correction systems allow us to rapidly satisfy task demands without necessarily committing to learning, as the relative permanence of learning may be inappropriate or inefficient when facing environments that are liable to change. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. The dynamic nature of systems consolidation: Stress during learning as a switch guiding the rate of the hippocampal dependency and memory quality.

    Science.gov (United States)

    Pedraza, Lizeth K; Sierra, Rodrigo O; Boos, Flávia Z; Haubrich, Josué; Quillfeldt, Jorge A; Alvares, Lucas de Oliveira

    2016-03-01

    Memory fades over time, becoming more schematic or abstract. The loss of contextual detail in memory may reflect a time-dependent change in the brain structures supporting memory. It has been well established that contextual fear memory relies on the hippocampus for expression shortly after learning, but it becomes hippocampus-independent at a later time point, a process called systems consolidation. This time-dependent process correlates with the loss of memory precision. Here, we investigated whether training intensity predicts the gradual decay of hippocampal dependency to retrieve memory, and the quality of the contextual memory representation over time. We have found that training intensity modulates the progressive decay of hippocampal dependency and memory precision. Strong training intensity accelerates systems consolidation and memory generalization in a remarkable timeframe match. The mechanisms underpinning such process are triggered by glucocorticoid and noradrenaline released during training. These results suggest that the stress levels during emotional learning act as a switch, determining the fate of memory quality. Moderate stress will create a detailed memory, whereas a highly stressful training will develop a generic gist-like memory. © 2015 Wiley Periodicals, Inc.

  4. Asymptotic normalization coefficients and astrophysical factors

    International Nuclear Information System (INIS)

    Mukhamedzhanov, A.M.; Azhari, A.; Clark, H.L.; Gagliardi, C.A.; Lui, Y.-W.; Sattarov, A.; Trache, L.; Tribble, R.E.; Burjan, V.; Kroha, V.; Carstoiu, F.

    2000-01-01

    The S factor for the direct capture reaction 7 Be(p,γ) 8 B can be found at astrophysical energies from the asymptotic normalization coefficients (ANC's) which provide the normalization of the tails of the overlap functions for 8 B → 7 Be + p. Peripheral transfer reactions offer a technique to determine these ANC's. Using this technique, the 10 B( 7 Be, 8 B) 9 Be and 14 N( 7 Be, 8 B) 13 C reactions have been used to measure the asymptotic normalization coefficient for 7 Be(p, γ) 8 B. These results provide an indirect determination of S 17 (0). Analysis of the existing 9 Be(p, γ) 10 B experimental data within the framework of the R-matrix method demonstrates that experimentally measured ANC's can provide a reasonable determination of direct radiative capture rates. (author)

  5. Higher air-change rates improve the learning performance of school children; 'Hoehere Lueftungsraten verbessern Lernverhalten von Schuelern'

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, W.

    2007-07-01

    In this interview with professor Olli Seppann, president of the REHVA congress, the connection between productivity and air-quality is discussed. The REHVA is the Federation of European Heating and Air-Conditioning Associations and organised the conference in 2007 in Helsinki, Finland. In the interview, the following areas of interest are addressed: Optimal internal climatic conditions with as little energy use as possible, the sick building syndrome, optimal temperatures for learning environments, conflicts between political efforts to reduce energy consumption, hygiene and productivity, measurement methods for airborne toxic substances, priorities set for the improvement of in-house climate, measurement and control systems for air-quality as well as possible further improvements in building automation systems. Finally, the question why much research in the area of comfort systems is carried out in Scandinavia is addressed.

  6. Explaining quantitative variation in the rate of Optional Infinitive errors across languages: a comparison of MOSAIC and the Variational Learning Model.

    Science.gov (United States)

    Freudenthal, Daniel; Pine, Julian; Gobet, Fernand

    2010-06-01

    In this study, we use corpus analysis and computational modelling techniques to compare two recent accounts of the OI stage: Legate & Yang's (2007) Variational Learning Model and Freudenthal, Pine & Gobet's (2006) Model of Syntax Acquisition in Children. We first assess the extent to which each of these accounts can explain the level of OI errors across five different languages (English, Dutch, German, French and Spanish). We then differentiate between the two accounts by testing their predictions about the relation between children's OI errors and the distribution of infinitival verb forms in the input language. We conclude that, although both accounts fit the cross-linguistic patterning of OI errors reasonably well, only MOSAIC is able to explain why verbs that occur more frequently as infinitives than as finite verb forms in the input also occur more frequently as OI errors than as correct finite verb forms in the children's output.

  7. Bicervical normal uterus with normal vagina | Okeke | Annals of ...

    African Journals Online (AJOL)

    To the best of our knowledge, only few cases of bicervical normal uterus with normal vagina exist in the literature; one of the cases had an anterior‑posterior disposition. This form of uterine abnormality is not explicable by the existing classical theory of mullerian anomalies and suggests that a complex interplay of events ...

  8. Group normalization for genomic data.

    Science.gov (United States)

    Ghandi, Mahmoud; Beer, Michael A

    2012-01-01

    Data normalization is a crucial preliminary step in analyzing genomic datasets. The goal of normalization is to remove global variation to make readings across different experiments comparable. In addition, most genomic loci have non-uniform sensitivity to any given assay because of variation in local sequence properties. In microarray experiments, this non-uniform sensitivity is due to different DNA hybridization and cross-hybridization efficiencies, known as the probe effect. In this paper we introduce a new scheme, called Group Normalization (GN), to remove both global and local biases in one integrated step, whereby we determine the normalized probe signal by finding a set of reference probes with similar responses. Compared to conventional normalization methods such as Quantile normalization and physically motivated probe effect models, our proposed method is general in the sense that it does not require the assumption that the underlying signal distribution be identical for the treatment and control, and is flexible enough to correct for nonlinear and higher order probe effects. The Group Normalization algorithm is computationally efficient and easy to implement. We also describe a variant of the Group Normalization algorithm, called Cross Normalization, which efficiently amplifies biologically relevant differences between any two genomic datasets.

  9. Group normalization for genomic data.

    Directory of Open Access Journals (Sweden)

    Mahmoud Ghandi

    Full Text Available Data normalization is a crucial preliminary step in analyzing genomic datasets. The goal of normalization is to remove global variation to make readings across different experiments comparable. In addition, most genomic loci have non-uniform sensitivity to any given assay because of variation in local sequence properties. In microarray experiments, this non-uniform sensitivity is due to different DNA hybridization and cross-hybridization efficiencies, known as the probe effect. In this paper we introduce a new scheme, called Group Normalization (GN, to remove both global and local biases in one integrated step, whereby we determine the normalized probe signal by finding a set of reference probes with similar responses. Compared to conventional normalization methods such as Quantile normalization and physically motivated probe effect models, our proposed method is general in the sense that it does not require the assumption that the underlying signal distribution be identical for the treatment and control, and is flexible enough to correct for nonlinear and higher order probe effects. The Group Normalization algorithm is computationally efficient and easy to implement. We also describe a variant of the Group Normalization algorithm, called Cross Normalization, which efficiently amplifies biologically relevant differences between any two genomic datasets.

  10. Normalizing the causality between time series

    Science.gov (United States)

    Liang, X. San

    2015-08-01

    Recently, a rigorous yet concise formula was derived to evaluate information flow, and hence the causality in a quantitative sense, between time series. To assess the importance of a resulting causality, it needs to be normalized. The normalization is achieved through distinguishing a Lyapunov exponent-like, one-dimensional phase-space stretching rate and a noise-to-signal ratio from the rate of information flow in the balance of the marginal entropy evolution of the flow recipient. It is verified with autoregressive models and applied to a real financial analysis problem. An unusually strong one-way causality is identified from IBM (International Business Machines Corporation) to GE (General Electric Company) in their early era, revealing to us an old story, which has almost faded into oblivion, about "Seven Dwarfs" competing with a giant for the mainframe computer market.

  11. Learning more by being taught less: A "time-for-self-study" theory explaining curricular effects on graduation rate and study duration

    NARCIS (Netherlands)

    H.G. Schmidt (Henk); J. Cohen-Schotanus (Janke); H.T. van der Molen (Henk); T.A.W. Splinter (Ted); C. van den Bulte (Christophe); R. Holdrinet (Rob); H.J.M. van Rossum (Herman)

    2010-01-01

    textabstractIn this article, an alternative for Tinto's integration theory of student persistence is proposed and tested. In the proposed theory, time available for individual study is considered a major determinant of both study duration and graduation rate of students in a particular curriculum.

  12. Learning more by being taught less : a "time-for-self-study" theory explaining curricular effects on graduation rate and study duration

    NARCIS (Netherlands)

    Schmidt, H.G.; Cohen-Schotanus, J.; van der Molen, H.T.; Splinter, T.A.W.; Bulte, J.; Holdrinet, R.; van Rossum, H.J.M.

    In this article, an alternative for Tinto's integration theory of student persistence is proposed and tested. In the proposed theory, time available for individual study is considered a major determinant of both study duration and graduation rate of students in a particular curriculum. In this view,

  13. Learning More by Being Taught Less: A "Time-for-Self-Study" Theory Explaining Curricular Effects on Graduation Rate and Study Duration

    Science.gov (United States)

    Schmidt, Henk G.; Cohen-Schotanus, Janke; van der Molen, Henk T.; Splinter, Ted A. W.; Bulte, Jan; Holdrinet, Rob; van Rossum, Herman J. M.

    2010-01-01

    In this article, an alternative for Tinto's integration theory of student persistence is proposed and tested. In the proposed theory, time available for individual study is considered a major determinant of both study duration and graduation rate of students in a particular curriculum. In this view, other activities in the curriculum, in…

  14. Comparison of spectrum normalization techniques for univariate ...

    Indian Academy of Sciences (India)

    Laser-induced breakdown spectroscopy; univariate study; normalization models; stainless steel; standard error of prediction. Abstract. Analytical performance of six different spectrum normalization techniques, namelyinternal normalization, normalization with total light, normalization with background along with their ...

  15. Mobile learning in medicine

    Science.gov (United States)

    Serkan Güllüoüǧlu, Sabri

    2013-03-01

    This paper outlines the main infrastructure for implicating mobile learning in medicine and present a sample mobile learning application for medical learning within the framework of mobile learning systems. Mobile technology is developing nowadays. In this case it will be useful to develop different learning environments using these innovations in internet based distance education. M-learning makes the most of being on location, providing immediate access, being connected, and acknowledges learning that occurs beyond formal learning settings, in places such as the workplace, home, and outdoors. Central to m-learning is the principle that it is the learner who is mobile rather than the device used to deliver m learning. The integration of mobile technologies into training has made learning more accessible and portable. Mobile technologies make it possible for a learner to have access to a computer and subsequently learning material and activities; at any time and in any place. Mobile devices can include: mobile phone, personal digital assistants (PDAs), personal digital media players (eg iPods, MP3 players), portable digital media players, portable digital multimedia players. Mobile learning (m-learning) is particularly important in medical education, and the major users of mobile devices are in the field of medicine. The contexts and environment in which learning occurs necessitates m-learning. Medical students are placed in hospital/clinical settings very early in training and require access to course information and to record and reflect on their experiences while on the move. As a result of this paper, this paper strives to compare and contrast mobile learning with normal learning in medicine from various perspectives and give insights and advises into the essential characteristics of both for sustaining medical education.

  16. Normal matter storage of antiprotons

    International Nuclear Information System (INIS)

    Campbell, L.J.

    1987-01-01

    Various simple issues connected with the possible storage of anti p in relative proximity to normal matter are discussed. Although equilibrium storage looks to be impossible, condensed matter systems are sufficiently rich and controllable that nonequilibrium storage is well worth pursuing. Experiments to elucidate the anti p interactions with normal matter are suggested. 32 refs

  17. The N'ormal Distribution

    Indian Academy of Sciences (India)

    An optimal way of choosing sample size in an opinion poll is indicated using the normal distribution. Introduction. In this article, the ubiquitous normal distribution is intro- duced as a convenient approximation for computing bino- mial probabilities for large values of n. Stirling's formula. • and DeMoivre-Laplace theorem ...

  18. An experimental study on the normal stress of magnetorheological fluids

    International Nuclear Information System (INIS)

    Jiang, Jile; Tian, Yu; Ren, Dongxue; Meng, Yonggang

    2011-01-01

    The dependence of the normal stress on the shear rate and magnetic field strength in the shear flow of magnetorheological (MR) fluids has been studied experimentally. An obvious normal stress could be observed when the applied magnetic field was higher than a critical value. The normal stress increases considerably with increase of the shear rate and magnetic field, and decreases suddenly and significantly upon the onset of shear thickening in MR fluids. The ratio of shear stress to normal stress, an analogue of the friction coefficient, increases with increase of the shear rate, but decreases with increase of the applied magnetic field. Along with the shear stress, the normal stress in MR fluids could provide a more comprehensive understanding of the MR effect, and the evolution of the particle structure in shear flow, and may have important implications for preparing high performance magnetostrictive elastomers with high force output along the magnetic field direction

  19. Learning How to Learn

    DEFF Research Database (Denmark)

    Lauridsen, Karen M.; Lauridsen, Ole

    Ole Lauridsen, Aarhus School of Business and Social Sciences, Aarhus University, Denmark Karen M. Lauridsen, Aarhus School of Business and Social Sciences, Aarhus University, Denmark Learning Styles in Higher Education – Learning How to Learn Applying learning styles (LS) in higher education...... by Constructivist learning theory and current basic knowledge of how the brain learns. The LS concept will thus be placed in a broader learning theoretical context as a strong learning and teaching tool. Participants will be offered the opportunity to have their own LS preferences established before...... teaching leads to positive results and enhanced student learning. However, learning styles should not only be considered a didactic matter for the teacher, but also a tool for the individual students to improve their learning capabilities – not least in contexts where information is not necessarily...

  20. Normal stress Sestamibi study: why re inject?

    International Nuclear Information System (INIS)

    Unger, S.A.; Hughes, T.

    2000-01-01

    Full text: Myocardial perfusion imaging (MPI) is widely used for risk stratification of patients with known or suspected coronary artery disease. A normal MPI study predicts an annual cardiac event rate of 99 Tc m -Sestamibi (MIBI), omitting the rest study when the post-stress study is interpreted as normal. The safety of this approach has not been validated, all published reports utilising both rest and stress images to interpret a study as 'normal'. Between 1/1/98 and 30/8/98, 489 patients (patients) were referred to our department for stress MPI. Of these, 237 were interpreted as normal on the basis of their post-stress study, and did not undergo a rest study. 12 month clinical follow-up was available in 184 (78%) of these patients, representing the study group (82 males, 102 females; mean age 61±12 years). 156 of these patients were referred for assessment of chest pain, three for dyspnoea, six for abnormal ECGs, and 19 for pre-operative evaluation. At one year of follow-up, there were no myocardial infarcts or admissions for unstable angina, and no cardiac deaths. Three patients died of non-cardiac causes. Seven patients underwent coronary angiography: five were normal, one had a single 50% stenosis, and one had an 80% vein graft stenosis which was subsequently angioplastied. In conclusion, a normal stress MIBI image predicts an excellent prognosis and negates the need for a rest reinjection study, thus reducing patient camera time and radiation exposure, improving departmental throughput, and minimising public health expenditure. Copyright (2000) The Australian and New Zealand Society of Nuclear Medicine Inc

  1. Metabolomics data normalization with EigenMS.

    Directory of Open Access Journals (Sweden)

    Yuliya V Karpievitch

    Full Text Available Liquid chromatography mass spectrometry has become one of the analytical platforms of choice for metabolomics studies. However, LC-MS metabolomics data can suffer from the effects of various systematic biases. These include batch effects, day-to-day variations in instrument performance, signal intensity loss due to time-dependent effects of the LC column performance, accumulation of contaminants in the MS ion source and MS sensitivity among others. In this study we aimed to test a singular value decomposition-based method, called EigenMS, for normalization of metabolomics data. We analyzed a clinical human dataset where LC-MS serum metabolomics data and physiological measurements were collected from thirty nine healthy subjects and forty with type 2 diabetes and applied EigenMS to detect and correct for any systematic bias. EigenMS works in several stages. First, EigenMS preserves the treatment group differences in the metabolomics data by estimating treatment effects with an ANOVA model (multiple fixed effects can be estimated. Singular value decomposition of the residuals matrix is then used to determine bias trends in the data. The number of bias trends is then estimated via a permutation test and the effects of the bias trends are eliminated. EigenMS removed bias of unknown complexity from the LC-MS metabolomics data, allowing for increased sensitivity in differential analysis. Moreover, normalized samples better correlated with both other normalized samples and corresponding physiological data, such as blood glucose level, glycated haemoglobin, exercise central augmentation pressure normalized to heart rate of 75, and total cholesterol. We were able to report 2578 discriminatory metabolite peaks in the normalized data (p<0.05 as compared to only 1840 metabolite signals in the raw data. Our results support the use of singular value decomposition-based normalization for metabolomics data.

  2. Evaluation of 14 winter bread wheat genotypes in normal irrigation ...

    African Journals Online (AJOL)

    Evaluation of 14 winter bread wheat genotypes in normal irrigation and stress conditions after anthesis stage. ... African Journal of Biotechnology ... Using biplot graphic method, comparison of indices amounts and mean rating of indices for ...

  3. Factors affecting dropout rates for teacher training courses in the first third of the twentieth in the Cordoba teacher training schools’ Factores de incidencia en el abandono de los estudios de magisterio en el primer tercio del siglo XX en las escuelas normales de Córdoba

    Directory of Open Access Journals (Sweden)

    Antonia RAMÍREZ GARCÍA

    2013-02-01

    Full Text Available The aim of this paper is to determine which variables affected the dropout rate for the academic curricula applied in 1903, 1914 and 1931. The application of the quantitative methodology to the History of the Education is limited, but it opens new options of investigation. The tool used to compile information was a questionnaire applied to a stratified sample of 618 subjects. Statistical inference was used to prove or disprove the hypotheses. The results revolved around the conditioning factors that affected the students, for example gender (52% and 48% for male and female students, respectively, 51.6% of the students followed an official curriculum, and the dropout rate was 45%. The findings indicate that the dropout rate was influenced by the gender, the curriculum studied and the mode of teaching chosen.El objetivo de esta investigación es la identificación de las variables intervinientes en el abandono de los estudios de magisterio en las Escuelas Normales cordobesas durante los planes de estudio de 1903, 1914 y 1931. La aplicación de la metodología cuantitativa a la Historia de la Educación es reducida, pero abre nuevas opciones de investigación. La herramienta de recogida de información empleada fue un cuestionario-plantilla aplicado a una muestra estratificada de 618 sujetos. Para probar o rechazar las hipótesis se recurrió a la estadística inferencial. Los resultados han girado alrededor de los condicionantes del alumnado: sexo (52 y 48% para hombres y mujeres respectivamente, seguimiento de una enseñanza oficial en el 51,6% del alumnado y del abandono de los estudios en el 45% de los casos. Las conclusiones señalan que el abandono de los estudios de magisterio quedó condicionado por el sexo del alumnado, el plan de estudios cursado y la modalidad de enseñanza seleccionada.

  4. Learning to Learn.

    Science.gov (United States)

    Weiss, Helen; Weiss, Martin

    1988-01-01

    The article reviews theories of learning (e.g., stimulus-response, trial and error, operant conditioning, cognitive), considers the role of motivation, and summarizes nine research-supported rules of effective learning. Suggestions are applied to teaching learning strategies to learning-disabled students. (DB)

  5. Sensorimotor Learning in a Computerized Athletic Training Battery.

    Science.gov (United States)

    Krasich, Kristina; Ramger, Ben; Holton, Laura; Wang, Lingling; Mitroff, Stephen R; Gregory Appelbaum, L

    2016-01-01

    Sensorimotor abilities are crucial for performance in athletic, military, and other occupational activities, and there is great interest in understanding learning in these skills. Here, behavioral performance was measured over three days as twenty-seven participants practiced multiple sessions on the Nike SPARQ Sensory Station (Nike, Inc., Beaverton, Oregon), a computerized visual and motor assessment battery. Wrist-worn actigraphy was recorded to monitor sleep-wake cycles. Significant learning was observed in tasks with high visuomotor control demands but not in tasks of visual sensitivity. Learning was primarily linear, with up to 60% improvement, but did not relate to sleep quality in this normal-sleeping population. These results demonstrate differences in the rate and capacity for learning across perceptual and motor domains, indicating potential targets for sensorimotor training interventions.

  6. Learning Pulse: Using Wearable Biosensors and Learning Analytics to Investigate and Predict Learning Success in Self-regulated Learning

    NARCIS (Netherlands)

    Di Mitri, Daniele; Scheffel, Maren; Drachsler, Hendrik; Börner, Dirk; Ternier, Stefaan; Specht, Marcus

    2017-01-01

    The Learning Pulse study aims to explore whether physiological data such as heart rate and step count correlate with learning activity data and whether they are good predictors for learning success during self-regulated learning. To verify this hypothesis an experiment was set up involving eight

  7. Tuned Normalization Explains the Size of Attention Modulations

    OpenAIRE

    Ni, Amy M.; Ray, Supratim; Maunsell, John H.R.

    2012-01-01

    The effect of attention on firing rates varies considerably within a single cortical area. The firing rate of some neurons is greatly modulated by attention while others are hardly affected. The reason for this variability across neurons is unknown. We found that the variability in attention modulation across neurons in area MT of macaques can be well explained by variability in the strength of tuned normalization across neurons. The presence of tuned normalization also explains a striking as...

  8. Environmental enrichment normalizes hippocampal timing coding in a malformed hippocampus.

    Directory of Open Access Journals (Sweden)

    Amanda E Hernan

    Full Text Available Neurodevelopmental insults leading to malformations of cortical development (MCD are a common cause of psychiatric disorders, learning impairments and epilepsy. In the methylazoxymethanol (MAM model of MCDs, animals have impairments in spatial cognition that, remarkably, are improved by post-weaning environmental enrichment (EE. To establish how EE impacts network-level mechanisms of spatial cognition, hippocampal in vivo single unit recordings were performed in freely moving animals in an open arena. We took a generalized linear modeling approach to extract fine spike timing (FST characteristics and related these to place cell fidelity used as a surrogate of spatial cognition. We find that MAM disrupts FST and place-modulated rate coding in hippocampal CA1 and that EE improves many FST parameters towards normal. Moreover, FST parameters predict spatial coherence of neurons, suggesting that mechanisms determining altered FST are responsible for impaired cognition in MCDs. This suggests that FST parameters could represent a therapeutic target to improve cognition even in the context of a brain that develops with a structural abnormality.

  9. Expression-robust 3D face recognition via weighted sparse representation of multi-scale and multi-component local normal patterns

    KAUST Repository

    Li, Huibin

    2014-06-01

    In the theory of differential geometry, surface normal, as a first order surface differential quantity, determines the orientation of a surface at each point and contains informative local surface shape information. To fully exploit this kind of information for 3D face recognition (FR), this paper proposes a novel highly discriminative facial shape descriptor, namely multi-scale and multi-component local normal patterns (MSMC-LNP). Given a normalized facial range image, three components of normal vectors are first estimated, leading to three normal component images. Then, each normal component image is encoded locally to local normal patterns (LNP) on different scales. To utilize spatial information of facial shape, each normal component image is divided into several patches, and their LNP histograms are computed and concatenated according to the facial configuration. Finally, each original facial surface is represented by a set of LNP histograms including both global and local cues. Moreover, to make the proposed solution robust to the variations of facial expressions, we propose to learn the weight of each local patch on a given encoding scale and normal component image. Based on the learned weights and the weighted LNP histograms, we formulate a weighted sparse representation-based classifier (W-SRC). In contrast to the overwhelming majority of 3D FR approaches which were only benchmarked on the FRGC v2.0 database, we carried out extensive experiments on the FRGC v2.0, Bosphorus, BU-3DFE and 3D-TEC databases, thus including 3D face data captured in different scenarios through various sensors and depicting in particular different challenges with respect to facial expressions. The experimental results show that the proposed approach consistently achieves competitive rank-one recognition rates on these databases despite their heterogeneous nature, and thereby demonstrates its effectiveness and its generalizability. © 2014 Elsevier B.V.

  10. Complete Normal Ordering 1: Foundations

    CERN Document Server

    Ellis, John; Skliros, Dimitri P.

    2016-01-01

    We introduce a new prescription for quantising scalar field theories perturbatively around a true minimum of the full quantum effective action, which is to `complete normal order' the bare action of interest. When the true vacuum of the theory is located at zero field value, the key property of this prescription is the automatic cancellation, to any finite order in perturbation theory, of all tadpole and, more generally, all `cephalopod' Feynman diagrams. The latter are connected diagrams that can be disconnected into two pieces by cutting one internal vertex, with either one or both pieces free from external lines. In addition, this procedure of `complete normal ordering' (which is an extension of the standard field theory definition of normal ordering) reduces by a substantial factor the number of Feynman diagrams to be calculated at any given loop order. We illustrate explicitly the complete normal ordering procedure and the cancellation of cephalopod diagrams in scalar field theories with non-derivative i...

  11. Investigating the widely held belief that men and women with learning disabilities receive poor quality healthcare when admitted to hospital: a single-site study of 30-day readmission rates.

    Science.gov (United States)

    Kelly, C L; Thomson, K; Wagner, A P; Waters, J P; Thompson, A; Jones, S; Holland, A J; Redley, M

    2015-09-01

    This study aims to use 30-day readmission rates to investigate the presumption that men and women with learning disabilities (LDs, known internationally as intellectual disabilities) receive poorer quality hospital care than their non-disabled peers. A 12-month retrospective audit was conducted using Hospital Episode Statistics (HES) at a single acute hospital in the East of England. This identified all in-patient admissions; admissions where the person concerned was recognised as having a LD; and all emergency readmissions within 30 days of discharge. Additionally, the healthcare records of all patients identified as having a LD and readmitted within 30 days as a medical emergency were examined in order to determine whether or not these readmissions were potentially preventable. Over the study period, a total of 66 870 adults were admitted as in-patients, among whom 7408 were readmitted as medical emergencies within 30 days of discharge: a readmission rate of 11%. Of these 66 870 patients, 256 were identified as having a LD, with 32 of them experiencing at least one emergency readmission within 30 days: a readmission rate of 13%. When examined, the healthcare records pertaining to these 32 patients who had a total of 39 unique 30-day readmissions revealed that 69% (n = 26) of these readmissions were potentially preventable. Although overall readmission rates were similar for patients with LDs and those from the general population, patients with LDs had a much higher rate of potentially preventable readmissions when compared to a general population estimate from van Walraven et al. This suggests that there is still work to be done to ensure that this patient population receives hospital care that is both safe and of high quality. © 2015 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

  12. The normal and pathological language

    OpenAIRE

    Espejo, Luis D.

    2014-01-01

    The extraordinary development of normal and pathological psychology has achieved in recent decades, thanks to the dual method of objective observation and oral survey enabled the researcher spirit of neuro-psychiatrist penetrate the intimate mechanism of the nervous system whose supreme manifestation is thought. It is normal psychology explaining the complicated game of perceptions: their methods of transmission, their centers of projection, its transformations and its synthesis to construct ...

  13. Is normal science good science?

    Directory of Open Access Journals (Sweden)

    Adrianna Kępińska

    2015-09-01

    Full Text Available “Normal science” is a concept introduced by Thomas Kuhn in The Structure of Scientific Revolutions (1962. In Kuhn’s view, normal science means “puzzle solving”, solving problems within the paradigm—framework most successful in solving current major scientific problems—rather than producing major novelties. This paper examines Kuhnian and Popperian accounts of normal science and their criticisms to assess if normal science is good. The advantage of normal science according to Kuhn was “psychological”: subjective satisfaction from successful “puzzle solving”. Popper argues for an “intellectual” science, one that consistently refutes conjectures (hypotheses and offers new ideas rather than focus on personal advantages. His account is criticized as too impersonal and idealistic. Feyerabend’s perspective seems more balanced; he argues for a community that would introduce new ideas, defend old ones, and enable scientists to develop in line with their subjective preferences. The paper concludes that normal science has no one clear-cut set of criteria encompassing its meaning and enabling clear assessment.

  14. nth roots of normal contractions

    International Nuclear Information System (INIS)

    Duggal, B.P.

    1992-07-01

    Given a complex separable Hilbert space H and a contraction A on H such that A n , n≥2 some integer, is normal it is shown that if the defect operator D A = (1 - A * A) 1/2 is of the Hilbert-Schmidt class, then A is similar to a normal contraction, either A or A 2 is normal, and if A 2 is normal (but A is not) then there is a normal contraction N and a positive definite contraction P of trace class such that parallel to A - N parallel to 1 = 1/2 parallel to P + P parallel to 1 (where parallel to · parallel to 1 denotes the trace norm). If T is a compact contraction such that its characteristics function admits a scalar factor, if T = A n for some integer n≥2 and contraction A with simple eigen-values, and if both T and A satisfy a ''reductive property'', then A is a compact normal contraction. (author). 16 refs

  15. Interest rates mapping

    Science.gov (United States)

    Kanevski, M.; Maignan, M.; Pozdnoukhov, A.; Timonin, V.

    2008-06-01

    The present study deals with the analysis and mapping of Swiss franc interest rates. Interest rates depend on time and maturity, defining term structure of the interest rate curves (IRC). In the present study IRC are considered in a two-dimensional feature space-time and maturity. Exploratory data analysis includes a variety of tools widely used in econophysics and geostatistics. Geostatistical models and machine learning algorithms (multilayer perceptron and Support Vector Machines) were applied to produce interest rate maps. IR maps can be used for the visualisation and pattern perception purposes, to develop and to explore economical hypotheses, to produce dynamic asset-liability simulations and for financial risk assessments. The feasibility of an application of interest rates mapping approach for the IRC forecasting is considered as well.

  16. The classification of normal screening mammograms

    Science.gov (United States)

    Ang, Zoey Z. Y.; Rawashdeh, Mohammad A.; Heard, Robert; Brennan, Patrick C.; Lee, Warwick; Lewis, Sarah J.

    2016-03-01

    Rationale and objectives: To understand how breast screen readers classify the difficulty of normal screening mammograms using common lexicon describing normal appearances. Cases were also assessed on their suitability for a single reader strategy. Materials and Methods: 15 breast readers were asked to interpret a test set of 29 normal screening mammogram cases and classify them by rating the difficulty of the case on a five-point Likert scale, identifying the salient features and assessing their suitability for single reading. Using the False Positive Fractions from a previous study, the 29 cases were classified into 10 "low", 10 "medium" and nine "high" difficulties. Data was analyzed with descriptive statistics. Spearman's correlation was used to test the strength of association between the difficulty of the cases and the readers' recommendation for single reading strategy. Results: The ratings from readers in this study corresponded to the known difficulty level of cases for the 'low' and 'high' difficulty cases. Uniform ductal pattern and density, symmetrical mammographic features and the absence of micro-calcifications were the main reasons associated with 'low' difficulty cases. The 'high' difficulty cases were described as having `dense breasts'. There was a statistically significant negative correlation between the difficulty of the cases and readers' recommendation for single reading (r = -0.475, P = 0.009). Conclusion: The findings demonstrated potential relationships between certain mammographic features and the difficulty for readers to classify mammograms as 'normal'. The standard Australian practice of double reading was deemed more suitable for most cases. There was an inverse moderate association between the difficulty of the cases and the recommendations for single reading.

  17. KARATE WITH CONSTRUCTIVE LEARNING

    Directory of Open Access Journals (Sweden)

    Srikrishna Karanam

    2012-02-01

    Full Text Available Any conventional learning process involves the traditional hierarchy of garnering of information and then recall gathered information. Constructive learning is an important research area having wide impact on teaching methods in education, learning theories, and plays a major role in many education reform movements. It is observed that constructive learning advocates the interconnection between emotions and learning. Human teachers identify the emotions of students with varying degrees of accuracy and can improve the learning rate of the students by motivating them. In learning with computers, computers also should be given the capability to recognize emotions so as to optimize the learning process. Image Processing is a very popular tool used in the process of establishing the theory of Constructive Learning. In this paper we use the Optical Flow computation in image sequences to analyze the accuracy of the moves of a karate player. We have used the Lucas-Kanade method for computing the optical flow in image sequences. A database consisting of optical flow images by a group of persons learning karate is formed and the learning rates are analyzed in order to main constructive learning. The contours of flow images are compared with the standard images and the error graphs are plotted. Analysis of the emotion of the amateur karate player is made by observing the error plots.

  18. Supporting Photovoltaics in Market-Rate Residential NewConstruction: A Summary of Programmatic Experience to Date and LessonsLearned

    Energy Technology Data Exchange (ETDEWEB)

    Barbose, Galen; Wiser, Ryan; Bolinger, Mark

    2006-02-10

    , particularly in ''hot'' housing markets where builders face little difficulty selling homes. Builders may also be concerned about the up-front cost of PV and its impact on new home prices and profits. The potential for project delays associated with PV module availability, installation scheduling, utility interconnection agreements, building inspections, permit processing, or other factors, may also be of great concern. Finally, many builders may believe that most homebuyers are not particularly interested in PV, given its cost, and that some may even be opposed based on concerns about aesthetics, maintenance, or reliability. In this paper, prepared on behalf of the Clean Energy States Alliance (CESA), we describe early efforts by state clean energy funds to support the deployment of PV in new, market-rate homes. (Other recent reports prepared for CESA describe experiences with programs targeting affordable housing.) We focus on the activities of clean energy funds in nine states that have funded specific projects and/or have offered targeted programs for PV in market-rate residential new construction. We also include in our review several other state or local organizations whose efforts are particularly noteworthy or have some direct bearing on the efforts of clean energy funds in the same state--however, we do not attempt to comprehensively review the activities of entities other than state clean energy funds.

  19. Learning Styles.

    Science.gov (United States)

    Missouri Univ., Columbia. Coll. of Education.

    Information is provided regarding major learning styles and other factors important to student learning. Several typically asked questions are presented regarding different learning styles (visual, auditory, tactile and kinesthetic, and multisensory learning), associated considerations, determining individuals' learning styles, and appropriate…

  20. Precaval retropancreatic space: Normal anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yeon Hee; Kim, Ki Whang; Kim, Myung Jin; Yoo, Hyung Sik; Lee, Jong Tae [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1992-07-15

    The authors defined precaval retropancreatic space as the space between pancreatic head with portal vein and IVC and analyzed the CT findings of this space to know the normal structures and size in this space. We evaluated 100 cases of normal abdominal CT scan to find out normal anatomic structures of precaval retropancreatic space retrospectively. We also measured the distance between these structures and calculated the minimum, maximum and mean values. At the splenoportal confluence level, normal structures between portal vein and IVC were vessel (21%), lymph node (19%), and caudate lobe of liver (2%) in order of frequency. The maximum AP diameter of portocaval lymph node was 4 mm. Common bile duct (CBD) was seen in 44% and the diameter was mean 3 mm and maximum 11 mm. CBD was located in extrapancreatic (75%) and lateral (60.6%) to pancreatic head. At IVC-left renal vein level, the maximum distance between CBD and IVC was 5 mm and the structure between posterior pancreatic surface and IVC was only fat tissue. Knowledge of these normal structures and measurement will be helpful in differentiating pancreatic mass with retropancreatic mass such as lymphadenopathy.

  1. Normal probability plots with confidence.

    Science.gov (United States)

    Chantarangsi, Wanpen; Liu, Wei; Bretz, Frank; Kiatsupaibul, Seksan; Hayter, Anthony J; Wan, Fang

    2015-01-01

    Normal probability plots are widely used as a statistical tool for assessing whether an observed simple random sample is drawn from a normally distributed population. The users, however, have to judge subjectively, if no objective rule is provided, whether the plotted points fall close to a straight line. In this paper, we focus on how a normal probability plot can be augmented by intervals for all the points so that, if the population distribution is normal, then all the points should fall into the corresponding intervals simultaneously with probability 1-α. These simultaneous 1-α probability intervals provide therefore an objective mean to judge whether the plotted points fall close to the straight line: the plotted points fall close to the straight line if and only if all the points fall into the corresponding intervals. The powers of several normal probability plot based (graphical) tests and the most popular nongraphical Anderson-Darling and Shapiro-Wilk tests are compared by simulation. Based on this comparison, recommendations are given in Section 3 on which graphical tests should be used in what circumstances. An example is provided to illustrate the methods. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. 3j Symbols: To Normalize or Not to Normalize?

    Science.gov (United States)

    van Veenendaal, Michel

    2011-01-01

    The systematic use of alternative normalization constants for 3j symbols can lead to a more natural expression of quantities, such as vector products and spherical tensor operators. The redefined coupling constants directly equate tensor products to the inner and outer products without any additional square roots. The approach is extended to…

  3. Semantic and phonological coding in poor and normal readers.

    Science.gov (United States)

    Vellutino, F R; Scanlon, D M; Spearing, D

    1995-02-01

    Three studies were conducted evaluating semantic and phonological coding deficits as alternative explanations of reading disability. In the first study, poor and normal readers in second and sixth grade were compared on various tests evaluating semantic development as well as on tests evaluating rapid naming and pseudoword decoding as independent measures of phonological coding ability. In a second study, the same subjects were given verbal memory and visual-verbal learning tasks using high and low meaning words as verbal stimuli and Chinese ideographs as visual stimuli. On the semantic tasks, poor readers performed below the level of the normal readers only at the sixth grade level, but, on the rapid naming and pseudoword learning tasks, they performed below the normal readers at the second as well as at the sixth grade level. On both the verbal memory and visual-verbal learning tasks, performance in poor readers approximated that of normal readers when the word stimuli were high in meaning but not when they were low in meaning. These patterns were essentially replicated in a third study that used some of the same semantic and phonological measures used in the first experiment, and verbal memory and visual-verbal learning tasks that employed word lists and visual stimuli (novel alphabetic characters) that more closely approximated those used in learning to read. It was concluded that semantic coding deficits are an unlikely cause of reading difficulties in most poor readers at the beginning stages of reading skills acquisition, but accrue as a consequence of prolonged reading difficulties in older readers. It was also concluded that phonological coding deficits are a probable cause of reading difficulties in most poor readers.

  4. Marrow transfusions into normal recipients

    International Nuclear Information System (INIS)

    Brecher, G.

    1983-01-01

    During the past several years we have explored the transfusion of bone marrow into normal nonirradiated mice. While transfused marrow proliferates readily in irradiated animals, only minimal proliferation takes place in nonirradiated recipients. It has generally been assumed that this was due to the lack of available proliferative sites in recipients with normal marrow. Last year we were able to report that the transfusion of 200 million bone marrow cells (about 2/3 of the total complement of marrow cells of a normal mouse) resulted in 20% to 25% of the recipient's marrow being replaced by donor marrow. Thus we can now study the behavior of animals that have been transfused (donor) and endogenous (recipient) marrow cells, although none of the tissues of either donor or recipient have been irradiated. With these animals we hope to investigate the nature of the peculiar phenomenon of serial exhaustion of marrow, also referred to as the limited self-replicability of stem cells

  5. The construction of normal expectations

    DEFF Research Database (Denmark)

    Quitzau, Maj-Britt; Røpke, Inge

    2008-01-01

    The gradual upward changes of standards in normal everyday life have significant environmental implications, and it is therefore important to study how these changes come about. The intention of the article is to analyze the social construction of normal expectations through a case study. The case...... concerns the present boom in bathroom renovations in Denmark, which offers an excellent opportunity to study the interplay between a wide variety of consumption drivers and social changes pointing toward long-term changes of normal expectations regarding bathroom standards. The study is problemoriented...... and transdisciplinary and draws on a wide range of sociological, anthropological, and economic theories. The empirical basis comprises a combination of statistics, a review of magazine and media coverage, visits to exhibitions, and qualitative interviews. A variety of consumption drivers are identified. Among...

  6. Rating Movies and Rating the Raters Who Rate Them.

    Science.gov (United States)

    Zhou, Hua; Lange, Kenneth

    2009-11-01

    The movie distribution company Netflix has generated considerable buzz in the statistics community by offering a million dollar prize for improvements to its movie rating system. Among the statisticians and computer scientists who have disclosed their techniques, the emphasis has been on machine learning approaches. This article has the modest goal of discussing a simple model for movie rating and other forms of democratic rating. Because the model involves a large number of parameters, it is nontrivial to carry out maximum likelihood estimation. Here we derive a straightforward EM algorithm from the perspective of the more general MM algorithm. The algorithm is capable of finding the global maximum on a likelihood landscape littered with inferior modes. We apply two variants of the model to a dataset from the MovieLens archive and compare their results. Our model identifies quirky raters, redefines the raw rankings, and permits imputation of missing ratings. The model is intended to stimulate discussion and development of better theory rather than to win the prize. It has the added benefit of introducing readers to some of the issues connected with analyzing high-dimensional data.

  7. Normalized cDNA libraries

    Science.gov (United States)

    Soares, Marcelo B.; Efstratiadis, Argiris

    1997-01-01

    This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3' noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library.

  8. Random Generators and Normal Numbers

    OpenAIRE

    Bailey, David H.; Crandall, Richard E.

    2002-01-01

    Pursuant to the authors' previous chaotic-dynamical model for random digits of fundamental constants, we investigate a complementary, statistical picture in which pseudorandom number generators (PRNGs) are central. Some rigorous results are achieved: We establish b-normality for constants of the form $\\sum_i 1/(b^{m_i} c^{n_i})$ for certain sequences $(m_i), (n_i)$ of integers. This work unifies and extends previously known classes of explicit normals. We prove that for coprime $b,c>1$ the...

  9. Learning Networks, Networked Learning

    NARCIS (Netherlands)

    Sloep, Peter; Berlanga, Adriana

    2010-01-01

    Sloep, P. B., & Berlanga, A. J. (2011). Learning Networks, Networked Learning [Redes de Aprendizaje, Aprendizaje en Red]. Comunicar, XIX(37), 55-63. Retrieved from http://dx.doi.org/10.3916/C37-2011-02-05

  10. Habit learning and the genetics of the dopamine D3 receptor: evidence from patients with schizophrenia and healthy controls.

    Science.gov (United States)

    Kéri, Szabolcs; Juhász, Anna; Rimanóczy, Agnes; Szekeres, György; Kelemen, Oguz; Cimmer, Csongor; Szendi, István; Benedek, György; Janka, Zoltán

    2005-06-01

    In this study, the authors investigated the relationship between the Ser9Gly (SG) polymorphism of the dopamine D3 receptor (DRD3) and striatal habit learning in healthy controls and patients with schizophrenia. Participants were given the weather prediction task, during which probabilistic cue-response associations were learned for tarot cards and weather outcomes (rain or sunshine). In both healthy controls and patients with schizophrenia, participants with Ser9Ser (SS) genotype did not learn during the early phase of the task (1-50 trials), whereas participants with SG genotype did so. During the late phase of the task (51-100 trials), both participants with SS and SG genotype exhibited significant learning. Learning rate was normal in patients with schizophrenia. These results suggest that the DRD3 variant containing glycine is associated with more efficient striatal habit learning in healthy controls and patients with schizophrenia. (c) 2005 APA, all rights reserved.

  11. About Learning Disabilities and NF

    Science.gov (United States)

    ... complica- tions of NF1 include: • Learning disabilities: Although intelligence is usually within the normal range, 50-60% ... and the ability to access meaning from the printed word. 5 Recent findings suggest that a high ...

  12. Complete normal ordering 1: Foundations

    Directory of Open Access Journals (Sweden)

    John Ellis

    2016-08-01

    Full Text Available We introduce a new prescription for quantising scalar field theories (in generic spacetime dimension and background perturbatively around a true minimum of the full quantum effective action, which is to ‘complete normal order’ the bare action of interest. When the true vacuum of the theory is located at zero field value, the key property of this prescription is the automatic cancellation, to any finite order in perturbation theory, of all tadpole and, more generally, all ‘cephalopod’ Feynman diagrams. The latter are connected diagrams that can be disconnected into two pieces by cutting one internal vertex, with either one or both pieces free from external lines. In addition, this procedure of ‘complete normal ordering’ (which is an extension of the standard field theory definition of normal ordering reduces by a substantial factor the number of Feynman diagrams to be calculated at any given loop order. We illustrate explicitly the complete normal ordering procedure and the cancellation of cephalopod diagrams in scalar field theories with non-derivative interactions, and by using a point splitting ‘trick’ we extend this result to theories with derivative interactions, such as those appearing as non-linear σ-models in the world-sheet formulation of string theory. We focus here on theories with trivial vacua, generalising the discussion to non-trivial vacua in a follow-up paper.

  13. Normal forms in Poisson geometry

    NARCIS (Netherlands)

    Marcut, I.T.

    2013-01-01

    The structure of Poisson manifolds is highly nontrivial even locally. The first important result in this direction is Conn's linearization theorem around fixed points. One of the main results of this thesis (Theorem 2) is a normal form theorem in Poisson geometry, which is the Poisson-geometric

  14. Mixed normal inference on multicointegration

    NARCIS (Netherlands)

    Boswijk, H.P.

    2009-01-01

    Asymptotic likelihood analysis of cointegration in I(2) models, see Johansen (1997, 2006), Boswijk (2000) and Paruolo (2000), has shown that inference on most parameters is mixed normal, implying hypothesis test statistics with an asymptotic 2 null distribution. The asymptotic distribution of the

  15. Is My Child's Appetite Normal?

    Science.gov (United States)

    Is My Child’s Appetite Normal? Cayla, who is 4 years old, did not finish her lunch. But she is ready to play. Her ... snack for later. That is okay! Your child’s appetite changes. Children do not grow as fast in ...

  16. Transforming Normal Programs by Replacement

    NARCIS (Netherlands)

    Bossi, Annalisa; Pettorossi, A.; Cocco, Nicoletta; Etalle, Sandro

    1992-01-01

    The replacement transformation operation, already defined in [28], is studied wrt normal programs. We give applicability conditions able to ensure the correctness of the operation wrt Fitting's and Kunen's semantics. We show how replacement can mimic other transformation operations such as thinning,

  17. Semigroups of data normalization functions

    NARCIS (Netherlands)

    Warrens, Matthijs J.

    2016-01-01

    Variable centering and scaling are functions that are typically used in data normalization. Various properties of centering and scaling functions are presented. It is shown that if we use two centering functions (or scaling functions) successively, the result depends on the order in which the

  18. Normalizing Catastrophe: Sustainability and Scientism

    Science.gov (United States)

    Bonnett, Michael

    2013-01-01

    Making an adequate response to our deteriorating environmental situation is a matter of ever increasing urgency. It is argued that a central obstacle to achieving this is the way that scientism has become normalized in our thinking about environmental issues. This is taken to reflect on an underlying "metaphysics of mastery" that vitiates proper…

  19. Neutron RBE for normal tissues

    International Nuclear Information System (INIS)

    Field, S.B.; Hornsey, S.

    1979-01-01

    RBE for various normal tissues is considered as a function of neutron dose per fraction. Results from a variety of centres are reviewed. It is shown that RBE is dependent on neutron energy and is tissue dependent, but is not specially high for the more critical tissues or for damage occurring late after irradiation. (author)

  20. Normal and abnormal growth plate

    International Nuclear Information System (INIS)

    Kumar, R.; Madewell, J.E.; Swischuk, L.E.

    1987-01-01

    Skeletal growth is a dynamic process. A knowledge of the structure and function of the normal growth plate is essential in order to understand the pathophysiology of abnormal skeletal growth in various diseases. In this well-illustrated article, the authors provide a radiographic classification of abnormal growth plates and discuss mechanisms that lead to growth plate abnormalities

  1. Transforming learning?

    Science.gov (United States)

    1999-09-01

    launch of the new Institute for Learning and Teaching in York. This has been established with the aim of raising standards of teaching in higher education and improving learning and teaching methods in universities and colleges. Teaching is felt to be at least as important as research in higher education, and the new Institute will oversee the quality of training programmes for higher education teachers, highlight examples of good practice throughout the UK, as well as recognize and reward good teaching. It will also help to administer teaching and learning support schemes on behalf of the Higher Education Funding Council for England, including a new #1m a year fund for national teaching fellowships. The Institute has been set up in response to recommendations in the Dearing Report on higher education, and will be an independent body supported by the teaching organisations, universities and colleges of higher education and the funding councils. Besides accrediting programmes of training and development, it will provide a range of services for members. Membership will be open to those engaged in teaching or learning support who have completed accredited training programmes or provided other evidence of eligibility. It is expected that membership of the institute will become a normal requirement for new teachers in higher education. Further information about the Institute may be obtained from the Institute for Learning and Teaching, Genesis 3, York Science Park, York YO10 5DQ (tel: 01904 434222, e-mail: enquiries@ilt.ac.uk).

  2. Database of normal human cerebral blood flow, cerebral blood volume, cerebral oxygen extraction fraction and cerebral metabolic rate of oxygen measured by positron emission tomography with {sup 15}O-labelled carbon dioxide or water, carbon monoxide and oxygen: a multicentre study in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hiroshi [Department of Radiology and Nuclear Medicine, Akita Research Institute of Brain and Blood Vessels, Akita (Japan); Department of Nuclear Medicine and Radiology, Division of Brain Sciences, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-Machi, 980-8575, Aoba-Ku, Sendai (Japan); Kanno, Iwao [Department of Radiology and Nuclear Medicine, Akita Research Institute of Brain and Blood Vessels, Akita (Japan); Kato, Chietsugu [Department of Nuclear Medicine, Hokkaido University School of Medicine, Sapporo (Japan); Sasaki, Toshiaki [Cyclotoron Research Center, Iwate Medical University, Morioka (Japan); Ishii, Kenji [Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, Tokyo (Japan); Ouchi, Yasuomi [Positron Medical Center, Hamamatsu Medical Center, Hamakita (Japan); Iida, Akihiko [Nagoya City Rehabilitation Center, Nagoya (Japan); Okazawa, Hidehiko [PET Unit, Research Institute, Shiga Medical Center, Moriyama (Japan); Hayashida, Kohei [Department of Radiology, National Cardiovascular Center, Suita, Osaka (Japan); Tsuyuguchi, Naohiro [Department of Neurosurgery, Osaka City University Medical School, Osaka (Japan); Ishii, Kazunari [Division of Imaging Research, Hyogo Institute for Aging Brain and Cognitive Disorders, Himeji, Hyogo (Japan); Kuwabara, Yasuo [Department of Radiology, Faculty of Medicine, Kyushu University, Fukuoka (Japan); Senda, Michio [Department of Image-based Medicine, Institute of Biomedical Research and Innovation, Kobe (Japan)

    2004-05-01

    Measurement of cerebral blood flow (CBF), cerebral blood volume (CBV), cerebral oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO{sub 2}) by positron emission tomography (PET) with oxygen-15 labelled carbon dioxide (C{sup 15}O{sub 2}) or {sup 15}O-labelled water (H{sub 2}{sup 15}O), {sup 15}O-labelled carbon monoxide (C{sup 15}O) and {sup 15}O-labelled oxygen ({sup 15}O{sub 2}) is useful for diagnosis and treatment planning in cases of cerebrovascular disease. The measured values theoretically depend on various factors, which may differ between PET centres. This study explored the applicability of a database of {sup 15}O-PET by examining between-centre and within-centre variation in values. Eleven PET centres participated in this multicentre study; seven used the steady-state inhalation method, one used build-up inhalation and three used bolus administration of C{sup 15}O{sub 2} (or H{sub 2}{sup 15}O) and {sup 15}O{sub 2}. All used C{sup 15}O for measurement of CBV. Subjects comprised 70 healthy volunteers (43 men and 27 women; mean age 51.8{+-}15.1 years). Overall mean{+-}SD values for cerebral cortical regions were: CBF=44.4{+-}6.5 ml 100 ml{sup -1} min{sup -1}; CBV=3.8{+-}0.7 ml 100 ml{sup -1}; OEF=0.44{+-}0.06; CMRO{sub 2}=3.3{+-}0.5 ml 100 ml{sup -1} min{sup -1}. Significant between-centre variation was observed in CBV, OEF and CMRO{sub 2} by one-way analysis of variance. However, the overall inter-individual variation in CBF, CBV, OEF and CMRO{sub 2} was acceptably small. Building a database of normal cerebral haemodynamics obtained by the{sup 15}O-PET methods may be practicable. (orig.)

  3. Correlations of memory and learning with vision in aged patients before and after a cataract operation.

    Science.gov (United States)

    Fagerström, R

    1992-12-01

    The connection between memory and learning with vision was investigated by studying 100 cataract operation patients, aged 71 to 76 years, 25 of them being men and 75 women. The cataract operation restored sufficient acuity of vision for reading (minimum E-test value 0.40) to 79% of the subjects. Short-term memory was studied with series of numbers, homogenic and heterogenic inhibition, and long sentences. Learning was tested with paired-associate learning and word learning. Psychological symptoms were measured on the Brief Psychiatric Rating Scale and personality on the Mini-Mult MMPI. Memory and learning improved significantly when vision was normalized after the cataract operation. Poor memory and learning scores correlated with monocular vision before the operation and with defects in the field of vision, due to glaucoma and exceeding 20%, postsurgery. Monocular vision and defects in the visual field caused a continuous sense of abnormalness, which impaired old people's ability to concentrate on tasks of memory and learning. Cerebrovascular disturbances, beginning dementia, and moderate psychological symptoms obstructed memory and learning on both test rounds. Depression was the most important psychological symptom contributing to poor memory and learning scores after the cataract operation. The memory and learning defects mainly reflected disturbances in memorizing.

  4. Ratings Revisited

    DEFF Research Database (Denmark)

    Lai, Signe Sophus

    2015-01-01

    tværs af medier og platforme, forskudt i tid og on-demand. This article focuses on audience ratings, which have functioned as the central ‘currency’ informing the media trade. It discusses changes to the production and accuracy of audience ratings at a time when established standards are being...

  5. Ureterocolonic anastomosis in clinically normal dogs

    International Nuclear Information System (INIS)

    Stone, E.A.; Walter, M.C.; Goldschmidt, M.H.; Biery, D.N.; Bovee, K.C.

    1988-01-01

    Ureterocolonic anastomosis was evaluated in 13 clinically normal dogs. Urinary continence was maintained after surgery, and the procedure was completed without technique errors in all but 2 dogs. Three dogs died within 5 weeks (2 of undetermined causes and 1 of aspiration pneumonia and neurologic disease), and 1 dog was euthanatized 4 months after surgery because of neurologic signs. Two healthy dogs were euthanatized 3 months after surgery for light microscopic evaluation of their kidneys. Five dogs were euthanatized 6 months after surgery for light microscopic evaluation of their kidneys. Gastrointestinal and neurologic disturbances developed in 4 dogs at various postoperative intervals. Plasma ammonia concentration measured in 2 dogs with neurologic signs was increased. Plasma ammonia concentration measured in 5 dogs without neurologic signs was within normal limits. All 5 dogs, in which metabolic acidosis was diagnosed, had high normal or above normal serum chloride concentration. Serum urea nitrogen values were increased after surgery because of colonic absorption of urea. Serum creatinine concentration was increased in 1 dog 6 months after surgery. Individual kidney glomerular filtration rate was reduced in 38% (3/8) of the kidneys from 4 other dogs at 6 months after surgery. Of 5 dogs euthanatized at 3 to 4 months after surgery, 4 had bilateral pyelitis, and 1 had unilateral pyelonephritis. Six months after surgery, pyelonephritis was diagnosed in 40% (4/10) of the kidneys from 5 dogs. The ureterocolonic anastomosis procedure is a salvage procedure that should allow complete cystectomy. However, variable degress of metabolic acidosis, hyperammonemia, and neurologic disease may result

  6. Extravascular transport in normal and tumor tissues.

    Science.gov (United States)

    Jain, R K; Gerlowski, L E

    1986-01-01

    The transport characteristics of the normal and tumor tissue extravascular space provide the basis for the determination of the optimal dosage and schedule regimes of various pharmacological agents in detection and treatment of cancer. In order for the drug to reach the cellular space where most therapeutic action takes place, several transport steps must first occur: (1) tissue perfusion; (2) permeation across the capillary wall; (3) transport through interstitial space; and (4) transport across the cell membrane. Any of these steps including intracellular events such as metabolism can be the rate-limiting step to uptake of the drug, and these rate-limiting steps may be different in normal and tumor tissues. This review examines these transport limitations, first from an experimental point of view and then from a modeling point of view. Various types of experimental tumor models which have been used in animals to represent human tumors are discussed. Then, mathematical models of extravascular transport are discussed from the prespective of two approaches: compartmental and distributed. Compartmental models lump one or more sections of a tissue or body into a "compartment" to describe the time course of disposition of a substance. These models contain "effective" parameters which represent the entire compartment. Distributed models consider the structural and morphological aspects of the tissue to determine the transport properties of that tissue. These distributed models describe both the temporal and spatial distribution of a substance in tissues. Each of these modeling techniques is described in detail with applications for cancer detection and treatment in mind.

  7. Factors Affecting the Normalization of CALL in Chinese Senior High Schools

    Science.gov (United States)

    He, Bi; Puakpong, Nattaya; Lian, Andrew

    2015-01-01

    With the development of Information Technology, increasing attention has been paid to Computer Assisted Language Learning (CALL). Meanwhile, increasing enthusiasm is seen for English learning and teaching in China. Yet, few research studies have focused on the normalization of CALL in ethnically diverse areas. In response to this research gap,…

  8. Aggregate Social Discount Rate Derived from Individual Discount Rates

    OpenAIRE

    Kenneth F. Reinschmidt

    2002-01-01

    In the economic evaluation of large public-sector projects, an aggregate social discount rate may be used in present worth comparison of alternatives. This paper uses the assumptions that individual discount rates are constant over time and approximately Normally distributed across the affected population, with mean \\mu and variance \\sigma 2 , to derive an aggregate discount function that is exponential in form but with time-dependent aggregate discount rate \\rho (t) = \\mu - \\sigma 2 t/2, whe...

  9. Superconducting versus normal conducting cavities

    CERN Document Server

    Podlech, Holger

    2013-01-01

    One of the most important issues of high-power hadron linacs is the choice of technology with respect to superconducting or room-temperature operation. The favour for a specific technology depends on several parameters such as the beam energy, beam current, beam power and duty factor. This contribution gives an overview of the comparison between superconducting and normal conducting cavities. This includes basic radiofrequency (RF) parameters, design criteria, limitations, required RF and plug power as well as case studies.

  10. Normal Movement Selectivity in Autism

    OpenAIRE

    Dinstein, Ilan; Thomas, Cibu; Humphreys, Kate; Minshew, Nancy; Behrmann, Marlene; Heeger, David J.

    2010-01-01

    It has been proposed that individuals with autism have difficulties understanding the goals and intentions of others because of a fundamental dysfunction in the mirror neuron system. Here, however, we show that individuals with autism exhibited not only normal fMRI responses in mirror system areas during observation and execution of hand movements, but also exhibited typical movement-selective adaptation (repetition suppression) when observing or executing the same movement repeatedly. Moveme...

  11. Visions of normality? Early experiences of radiographic reporting

    Energy Technology Data Exchange (ETDEWEB)

    Reeves, Pauline E-mail: pauline.reeves@whnt.nhs.uk

    2004-08-01

    This article reflects on my early [student] experiences in learning to undertake radiographic reporting and uses critical incidents to highlight two areas of error during this period. These errors include perceptual (optical illusions and, in particular, the Mach band effect) and lack of subject specific knowledge (specifically anatomical knowledge--especially of normal anatomical variants). These two errors are analysed in the wider context of radiological error and the difficulty in reaching consensus even between experienced reporters.

  12. Visions of normality? Early experiences of radiographic reporting

    International Nuclear Information System (INIS)

    Reeves, Pauline

    2004-01-01

    This article reflects on my early [student] experiences in learning to undertake radiographic reporting and uses critical incidents to highlight two areas of error during this period. These errors include perceptual (optical illusions and, in particular, the Mach band effect) and lack of subject specific knowledge (specifically anatomical knowledge--especially of normal anatomical variants). These two errors are analysed in the wider context of radiological error and the difficulty in reaching consensus even between experienced reporters

  13. Lithium control during normal operation

    International Nuclear Information System (INIS)

    Suryanarayan, S.; Jain, D.

    2010-01-01

    Periodic increases in lithium (Li) concentrations in the primary heat transport (PHT) system during normal operation are a generic problem at CANDU® stations. Lithiated mixed bed ion exchange resins are used at stations for pH control in the PHT system. Typically tight chemistry controls including Li concentrations are maintained in the PHT water. The reason for the Li increases during normal operation at CANDU stations such as Pickering was not fully understood. In order to address this issue a two pronged approach was employed. Firstly, PNGS-A data and information from other available sources was reviewed in an effort to identify possible factors that may contribute to the observed Li variations. Secondly, experimental studies were carried out to assess the importance of these factors in order to establish reasons for Li increases during normal operation. Based on the results of these studies, plausible mechanisms/reasons for Li increases have been identified and recommendations made for proactive control of Li concentrations in the PHT system. (author)

  14. Normalization of Gravitational Acceleration Models

    Science.gov (United States)

    Eckman, Randy A.; Brown, Aaron J.; Adamo, Daniel R.

    2011-01-01

    Unlike the uniform density spherical shell approximations of Newton, the con- sequence of spaceflight in the real universe is that gravitational fields are sensitive to the nonsphericity of their generating central bodies. The gravitational potential of a nonspherical central body is typically resolved using spherical harmonic approximations. However, attempting to directly calculate the spherical harmonic approximations results in at least two singularities which must be removed in order to generalize the method and solve for any possible orbit, including polar orbits. Three unique algorithms have been developed to eliminate these singularities by Samuel Pines [1], Bill Lear [2], and Robert Gottlieb [3]. This paper documents the methodical normalization of two1 of the three known formulations for singularity-free gravitational acceleration (namely, the Lear [2] and Gottlieb [3] algorithms) and formulates a general method for defining normalization parameters used to generate normalized Legendre Polynomials and ALFs for any algorithm. A treatment of the conventional formulation of the gravitational potential and acceleration is also provided, in addition to a brief overview of the philosophical differences between the three known singularity-free algorithms.

  15. "Ser diferente é normal?"/"Being different: is it normal?"

    Directory of Open Access Journals (Sweden)

    Viviane Veras

    2007-01-01

    Full Text Available A pergunta título deste trabalho retoma o slogan “Ser diferente é normal”, que é parte da campanha criada para uma organização não-governamental que atende portadores de Síndrome de Down. O objetivo é a inclusão social da pessoa com deficiência e o primeiro passo foi propor a inclusão de um grupo de diferentes no grupo dito normal. No vídeo de lançamento da campanha, o diferente, identificado como normal, é mostrado por meio de exemplos – um negro com cabelo black-power, um skin-head, um corpo tatuado, um corpo feminino halterofílico, uma família hippie, uma garota com síndrome de Down. A visão da adolescente dançando reduz, de certo modo, o efeito imaginário que vai além da síndrome, uma vez que apenas o corpo com seus olhinhos puxados se destacam, e não se interrogam questões cognitivas. Minha proposta é refletir sobre o estatuto paradoxal do exemplo, tal como é trabalhado nesse vídeo: se, por definição, um exemplo mostra de fato seu pertencimento a uma classe, pode-se concluir que é exatamente por ser exemplar que ele se encontra fora dela, no exato momento em que a exibe e define. The question in the title of this paper refers to the slogan "ser diferente é normal" ("It´s normal to be different", which is part of a campaign created for a NGO that supports people with Down syndrome. The objective of the campaign is to promote the social inclusion of individuals with Down syndrome, and the first step was to propose the inclusion of a group of "differents" in the so-called normal group. The film launching the campaign shows the different identified as normal by means of examples: a black man exhibiting blackpower haircut, a skin-head, a tattooed body, an over-athletic female body, a hippie family and a girl with Down syndrome. The vision of the dancing teenager lessens the imaginary effect that surpasses the syndrome, since only her body and her little oriental eyes stand out and no cognitive issues are

  16. Normal Hg uptake values in children under 4 years old

    International Nuclear Information System (INIS)

    Raynaud, C.

    1976-01-01

    At birth the child's kidney is anatomically and functionally immature and the Hg uptake rate is only a quarter that of an adult. At 12 months this value is already 3/4 that of the adult and the final normal mature values are reached between 3 and 4 years. A curve of normal values for children below 4 years old is proposed, though being based on a small number of measurements only it must be taken as provisional [fr

  17. Understanding a Normal Distribution of Data.

    Science.gov (United States)

    Maltenfort, Mitchell G

    2015-12-01

    Assuming data follow a normal distribution is essential for many common statistical tests. However, what are normal data and when can we assume that a data set follows this distribution? What can be done to analyze non-normal data?

  18. Quantiles for Finite Mixtures of Normal Distributions

    Science.gov (United States)

    Rahman, Mezbahur; Rahman, Rumanur; Pearson, Larry M.

    2006-01-01

    Quantiles for finite mixtures of normal distributions are computed. The difference between a linear combination of independent normal random variables and a linear combination of independent normal densities is emphasized. (Contains 3 tables and 1 figure.)

  19. Learning Problems

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Learning Problems KidsHealth / For Kids / Learning Problems What's in ... for how to make it better. What Are Learning Disabilities? Learning disabilities aren't contagious, but they ...

  20. Peripartum haemodynamic status of bitches with normal birth or dystocia.

    Science.gov (United States)

    Lúcio, C F; Silva, L C G; Rodrigues, J A; Veiga, G A L; Vannucchi, C I

    2009-07-01

    There has been limited investigation of parturition in the bitch and there is little information published on clinical and obstetrical examination other than opinion and anecdote. While there are substantial data on haemodynamic and vascular changes during normal parturition in humans, little is known about the physiological events in the dog. This study was aimed at maternal haemodynamic changes occurring during normal parturition and to investigate how these were modified in bitches with dystocia (DYST) treated either medically or via assisted delivery and caesarean operation. Three groups of 10 bitches were investigated; those with normal parturition, those with DYST corrected by manipulative assistance or caesarean operation and those with uterine inertia treated by oxytocin administration. Heart rate, systolic and diastolic blood pressure, electrocardiogram and blood glucose concentration were measured pre-partum, intra-partum, immediately after parturition and 1 h later. Heart rate was high at all times throughout the study and the majority of bitches had normal sinus rhythm. Blood pressure was generally within the normal range, and although systolic and diastolic blood pressure was highest during the intra-partum period and sometimes during the immediate post-partum period, there were no significant differences between groups. All bitches had blood glucose concentrations within the normal range throughout the study although pre-partum concentrations were statistically lower than many of the other time periods. The study provides useful physiological data that will facilitate monitoring and clinical management of bitches throughout normal parturition and DYST.