Moderate Learning Difficulties: Searching for Clarity and Understanding

ERIC Educational Resources Information Center

Norwich, Brahm; Ylonen, Annamari; Gwernan-Jones, Ruth

2014-01-01

The concept of moderate learning difficulties (MLD) is not clearly understood in its definition and in its general use. Nevertheless, as a distinct area of special educational needs (SEN) this category has constituted about a quarter of all of those pupils identified as having SEN in England. This paper reports the analysis of findings from an…

Mathematics achievement and anxiety and their relation to internalizing and externalizing behaviors.

PubMed

Wu, Sarah S; Willcutt, Erik G; Escovar, Emily; Menon, Vinod

2014-01-01

Although behavioral difficulties are well documented in reading disabilities, little is known about the relationship between math ability and internalizing and externalizing behaviors. Here, we use standardized measures to investigate the relation among early math ability, math anxiety, and internalizing and externalizing behaviors in a group of 366 second and third graders. Math achievement was significantly correlated with attentional difficulties and social problems but not with internalizing symptoms. The relation between math achievement and externalizing behavioral problems was stronger in girls than in boys. Math achievement was not correlated with trait anxiety but was negatively correlated with math anxiety. Critically, math anxiety differed significantly between children classified as math learning disabled (MLD), low achieving (LA), and typically developing (TD), with math anxiety significantly higher in the MLD and LA groups compared to the TD group. Our findings suggest that, even in nonclinical samples, math difficulties at the earliest stages of formal math learning are associated with attentional difficulties and domain-specific anxiety. These findings underscore the need for further examination of the shared cognitive, neural, and genetic influences underlying problem solving and nonverbal learning difficulties and accompanying internalizing and externalizing behaviors. © Hammill Institute on Disabilities 2013.

Mathematics Achievement and Anxiety and Their Relation to Internalizing and Externalizing Behaviors

PubMed Central

Wu, Sarah S.; Willcutt, Erik G.; Escovar, Emily; Menon, Vinod

2013-01-01

Although behavioral difficulties are well documented in reading disabilities, little is known about the relationship between math ability and internalizing and externalizing behaviors. Here, we use standardized measures to investigate the relation among early math ability, math anxiety, and internalizing and externalizing behaviors in a group of 366 second and third graders. Math achievement was significantly correlated with attentional difficulties and social problems but not with internalizing symptoms. The relation between math achievement and externalizing behavioral problems was stronger in girls than in boys. Math achievement was not correlated with trait anxiety but was negatively correlated with math anxiety. Critically, math anxiety differed significantly between children classified as math learning disabled (MLD), low achieving (LA), and typically developing (TD), with math anxiety significantly higher in the MLD and LA groups compared to the TD group. Our findings suggest that, even in nonclinical samples, math difficulties at the earliest stages of formal math learning are associated with attentional difficulties and domain-specific anxiety. These findings underscore the need for further examination of the shared cognitive, neural, and genetic influences underlying problem solving and nonverbal learning difficulties and accompanying internalizing and externalizing behaviors. PMID:23313869

Embedding Number-Combinations Practice Within Word-Problem Tutoring

PubMed Central

Powell, Sarah R.; Fuchs, Lynn S.; Fuchs, Douglas

2012-01-01

Two aspects of mathematics with which students with mathematics learning difficulty (MLD) often struggle are word problems and number-combination skills. This article describes a math program in which students receive instruction on using algebraic equations to represent the underlying problem structure for three word-problem types. Students also learn counting strategies for answering number combinations that they cannot retrieve from memory. Results from randomized-control trials indicated that embedding the counting strategies for number combinations produces superior word-problem and number-combination outcomes for students with MLD beyond tutoring programs that focus exclusively on number combinations or word problems. PMID:22661880

Embedding Number-Combinations Practice Within Word-Problem Tutoring.

PubMed

Powell, Sarah R; Fuchs, Lynn S; Fuchs, Douglas

2010-09-01

Two aspects of mathematics with which students with mathematics learning difficulty (MLD) often struggle are word problems and number-combination skills. This article describes a math program in which students receive instruction on using algebraic equations to represent the underlying problem structure for three word-problem types. Students also learn counting strategies for answering number combinations that they cannot retrieve from memory. Results from randomized-control trials indicated that embedding the counting strategies for number combinations produces superior word-problem and number-combination outcomes for students with MLD beyond tutoring programs that focus exclusively on number combinations or word problems.

The Relationship between Vocabulary, Grammar, and False Belief Task Performance in Children with Autistic Spectrum Disorders and Children with Moderate Learning Difficulties

ERIC Educational Resources Information Center

Fisher, Naomi; Happe, Francesca; Dunn, Judy

2005-01-01

Background: The aim of this study was to examine the relationship between language and theory of mind in children with autistic spectrum disorders (ASD) and children with moderate learning difficulties (MLD). Previous studies have found a strong association between language and theory of mind in a range of groups, but mostly have not included…

Expressive drawing ability in children with autism.

PubMed

Jolley, Richard P; O'Kelly, Rachael; Barlow, Claire M; Jarrold, Christopher

2013-03-01

The autistic impairments in emotional and social competence, imagination and generating ideas predict qualitative differences in expressive drawings by children with autism beyond that accounted by any general learning difficulties. In a sample of 60 5-19-year-olds, happy and sad drawings were requested from 15 participants with non-savant autism and compared with those drawn by three control groups matched on either degree of learning difficulty (MLD), mental age (MA) or chronological age (CA). All drawings were rated by two artists on a 7-point quality of expression scale. Contrary to our predictions, the drawings from the autistic group were rated similar to those of the MA and MLD groups. Analysis of the people and social content of the drawings revealed that although children with autism did not draw fewer people, they did draw more immature forms than mental age controls. Furthermore, there was tentative evidence that fewer social scenes were produced by the autism sample. We conclude that the overall merit of expressive drawing in autism is commensurate with their general learning difficulties, but the social/emotional impairment in autism affects their drawings of people and social scenes. © 2013 The British Psychological Society.

Effects of Enhanced Anchored Instruction on Skills Aligned to Common Core Math Standards

ERIC Educational Resources Information Center

Bottge, Brian A.; Cho, Sun-Joo

2013-01-01

This study compared how students with learning difficulties in math (MLD) who were randomly assigned to two instructional conditions answered items on problem solving tests aligned to the Common Core State Standards Initiative for Mathematics. Posttest scores showed improvement in the math performance of students receiving Enhanced Anchored…

[New trends in the evaluation of mathematics learning disabilities. The role of metacognition].

PubMed

Miranda-Casas, A; Acosta-Escareño, G; Tarraga-Minguez, R; Fernández, M I; Rosel-Remírez, J

2005-01-15

The current trends in the evaluation of mathematics learning disabilities (MLD), based on cognitive and empirical models, are oriented towards combining procedures involving the criteria and the evaluation of cognitive and metacognitive processes, associated to performance in mathematical tasks. The objective of this study is to analyse the metacognitive skills of prediction and evaluation in performing maths tasks and to compare metacognitive performance among pupils with MLD and younger pupils without MLD, who have the same level of mathematical performance. Likewise, we analyse these pupils' desire to learn. Subjects and methods. We compare a total of 44 pupils from the second cycle of primary education (8-10 years old) with and without mathematics learning disabilities. Significant differences are observed between pupils with and without mathematics learning disabilities in their capacity to predict and assess all of the tasks evaluated. As regards their 'desire to learn', no significant differences were found between pupils with and without MLD, which indicated that those with MLD assess their chances of successfully performing maths tasks in the same way as those without MLD. Finally, the findings reveal a similar metacognitive profile in pupils with MLD and the younger pupils with no mathematics learning disabilities. In future studies we consider it important to analyse the influence of the socio-affective belief system in the use of metacognitive skills.

[Differential diagnosis of primary and secondary mathematical learning disability – indications from the dyscalculia test Basis-Math 4–8].

PubMed

Krinzinger, Helga

2016-09-01

Studies in children with AD(H)D without mathematical learning disability (MLD) as well as studies on the effects of methylphenidate on arithmetic have shown that most deficits in mathematics and most error types commonly described as specific to developmental dyscalculia (e. g., finger-counting, fact-retrieval deficit, complex counting, difficulties with carry/borrow procedures, self-corrections) cannot be classified as such and should thus not be used for the differential diagnosis of primary dyscalculia and secondary MLD. This article proposes using the overall score in the dyscalculia test Basis-Math 4-8 (Moser Opitz et al., 2010) as well as implausible subtraction errors as a marker for dyscalculia and the number of self-corrections made during the test as a cognitive marker for attention deficits. Hierarchical cluster analyses were calculated in a sample of 51 clinically referred children with normal IQ and suspicion of MLD, using IQ, years of schooling, overall score of the Basis-Math 4–8 and number of self-corrections in this test as variables. The results revealed a subgroup with primary dyscalculia as well as three subgroups with secondary MLD (two with attention deficit hyperactivity disorder, one with depression and one small subgroup with high IQ). In conclusion, the Basis-Math 4–8 (Moser Opitz et al., 2010) can offer substantial information for the differential diagnosis of dyscalculia and secondary deficits in mathematics due to attention problems and enable optimization of treatment decisions for the different groups.

Taking Stock of 40 Years of Research on Mathematical Learning Disability: Methodological Issues and Future Directions

ERIC Educational Resources Information Center

Lewis, Katherine E.; Fisher, Marie B.

2016-01-01

Although approximately 5-8% of students have a mathematical learning disability (MLD), researchers have yet to develop a consensus operational definition. To examine how MLD has been identified and what mathematics topics have been explored, the authors conducted a systematic review of 165 studies on MLD published between 1974 and 2013. To move…

Subtypes and comorbidity in mathematical learning disabilities: Multidimensional study of verbal and visual memory processes is key to understanding.

PubMed

Szűcs, D

2016-01-01

A large body of research suggests that mathematical learning disability (MLD) is related to working memory impairment. Here, I organize part of this literature through a meta-analysis of 36 studies with 665 MLD and 1049 control participants. I demonstrate that one subtype of MLD is associated with reading problems and weak verbal short-term and working memory. Another subtype of MLD does not have associated reading problems and is linked to weak visuospatial short-term and working memory. In order to better understand MLD we need to precisely define potentially modality-specific memory subprocesses and supporting executive functions, relevant for mathematical learning. This can be achieved by taking a multidimensional parametric approach systematically probing an extended network of cognitive functions. Rather than creating arbitrary subgroups and/or focus on a single factor, highly powered studies need to position individuals in a multidimensional parametric space. This will allow us to understand the multidimensional structure of cognitive functions and their relationship to mathematical performance. © 2016 Elsevier B.V. All rights reserved.

Kindergarten Predictors of Math Learning Disability

PubMed Central

Mazzocco, Michèle M. M.; Thompson, Richard E.

2009-01-01

The aim of the present study was to address how to effectively predict mathematics learning disability (MLD). Specifically, we addressed whether cognitive data obtained during kindergarten can effectively predict which children will have MLD in third grade, whether an abbreviated test battery could be as effective as a standard psychoeducational assessment at predicting MLD, and whether the abbreviated battery corresponded to the literature on MLD characteristics. Participants were 226 children who enrolled in a 4-year prospective longitudinal study during kindergarten. We administered measures of mathematics achievement, formal and informal mathematics ability, visual-spatial reasoning, and rapid automatized naming and examined which test scores and test items from kindergarten best predicted MLD at grades 2 and 3. Statistical models using standardized scores from the entire test battery correctly classified ~80–83 percent of the participants as having, or not having, MLD. Regression models using scores from only individual test items were less predictive than models containing the standard scores, except for models using a specific subset of test items that dealt with reading numerals, number constancy, magnitude judgments of one-digit numbers, or mental addition of one-digit numbers. These models were as accurate in predicting MLD as was the model including the entire set of standard scores from the battery of tests examined. Our findings indicate that it is possible to effectively predict which kindergartners are at risk for MLD, and thus the findings have implications for early screening of MLD. PMID:20084182

Cognitive tutoring induces widespread neuroplasticity and remediates brain function in children with mathematical learning disabilities.

PubMed

Iuculano, Teresa; Rosenberg-Lee, Miriam; Richardson, Jennifer; Tenison, Caitlin; Fuchs, Lynn; Supekar, Kaustubh; Menon, Vinod

2015-09-30

Competency with numbers is essential in today's society; yet, up to 20% of children exhibit moderate to severe mathematical learning disabilities (MLD). Behavioural intervention can be effective, but the neurobiological mechanisms underlying successful intervention are unknown. Here we demonstrate that eight weeks of 1:1 cognitive tutoring not only remediates poor performance in children with MLD, but also induces widespread changes in brain activity. Neuroplasticity manifests as normalization of aberrant functional responses in a distributed network of parietal, prefrontal and ventral temporal-occipital areas that support successful numerical problem solving, and is correlated with performance gains. Remarkably, machine learning algorithms show that brain activity patterns in children with MLD are significantly discriminable from neurotypical peers before, but not after, tutoring, suggesting that behavioural gains are not due to compensatory mechanisms. Our study identifies functional brain mechanisms underlying effective intervention in children with MLD and provides novel metrics for assessing response to intervention.

Cognitive characteristics of children with mathematics learning disability (MLD) vary as a function of the cutoff criterion used to define MLD.

PubMed

Murphy, Melissa M; Mazzocco, Michèle M M; Hanich, Laurie B; Early, Martha C

2007-01-01

Researchers of mathematics learning disability (MLD) commonly use cutoff scores to determine which participants have MLD. Some researchers apply more restrictive cutoffs than others (e.g., performance below the 10th vs. below the 35th percentile). Different cutoffs may lead to groups of children that differ in their profile of math and related skills, including reading, visual-spatial, and working memory skills. The present study assesses the characteristics of children with MLD based on varying MLD definitions of math performance either below the 10th percentile (n = 22) or between the 11th and 25th percentile (n = 42) on the Test of Early Math Ability, second edition (TEMA-2). Initial starting levels and growth rates for math and related skills were examined in these two MLD groups relative to a comparison group (n = 146) whose TEMA-2 performance exceeded the 25th percentile. Between kindergarten and third grade, differences emerged in the starting level and growth rate, suggesting qualitative differences among the three groups. Despite some similarities, qualitative group differences were also observed in the profiles of math-related skills across groups. These results highlight differences in student characteristics based on the definition of MLD and illustrate the value of examining skill areas associated with math performance in addition to math performance itself.

Impaired acuity of the approximate number system underlies mathematical learning disability (dyscalculia)

PubMed Central

Mazzocco, Michèle M. M.; Feigenson, Lisa; Halberda, Justin

2015-01-01

Many children have significant mathematical learning disabilities (MLD, or dyscalculia) despite adequate schooling. We hypothesize that MLD partly results from a deficiency in the Approximate Number System (ANS) that supports nonverbal numerical representations across species and throughout development. Here we show that ninth grade students with MLD have significantly poorer ANS precision than students in all other mathematics achievement groups (low-, typically-, and high-achieving), as measured by psychophysical assessments of ANS acuity (w) and of the mappings between ANS representations and number words (cv). This relationship persists even when controlling for domain-general abilities. Furthermore, this ANS precision does not differentiate low- from typically-achieving students, suggesting an ANS deficit that is specific to MLD. PMID:21679173

Impaired Acuity of the Approximate Number System Underlies Mathematical Learning Disability (Dyscalculia)

ERIC Educational Resources Information Center

Mazzocco, Michele M. M.; Feigenson, Lisa; Halberda, Justin

2011-01-01

Many children have significant mathematical learning disabilities (MLD, or dyscalculia) despite adequate schooling. The current study hypothesizes that MLD partly results from a deficiency in the Approximate Number System (ANS) that supports nonverbal numerical representations across species and throughout development. In this study of 71 ninth…

Mathematical Learning Disabilities in Special Populations: Phenotypic Variation and Cross-Disorder Comparisons

ERIC Educational Resources Information Center

Dennis, Maureen; Berch, Daniel B.; Mazzocco, Michele M. M.

2009-01-01

What is mathematical learning disability (MLD)? The reviews in this special issue adopt different approaches to defining the construct of MLD. Collectively, they demonstrate the current status of efforts to establish a consensus definition and the challenges faced in this endeavor. In this commentary, we reflect upon the proposed pathways to…

Cognitive tutoring induces widespread neuroplasticity and remediates brain function in children with mathematical learning disabilities

PubMed Central

Iuculano, Teresa; Rosenberg-Lee, Miriam; Richardson, Jennifer; Tenison, Caitlin; Fuchs, Lynn; Supekar, Kaustubh; Menon, Vinod

2015-01-01

Competency with numbers is essential in today's society; yet, up to 20% of children exhibit moderate to severe mathematical learning disabilities (MLD). Behavioural intervention can be effective, but the neurobiological mechanisms underlying successful intervention are unknown. Here we demonstrate that eight weeks of 1:1 cognitive tutoring not only remediates poor performance in children with MLD, but also induces widespread changes in brain activity. Neuroplasticity manifests as normalization of aberrant functional responses in a distributed network of parietal, prefrontal and ventral temporal–occipital areas that support successful numerical problem solving, and is correlated with performance gains. Remarkably, machine learning algorithms show that brain activity patterns in children with MLD are significantly discriminable from neurotypical peers before, but not after, tutoring, suggesting that behavioural gains are not due to compensatory mechanisms. Our study identifies functional brain mechanisms underlying effective intervention in children with MLD and provides novel metrics for assessing response to intervention. PMID:26419418

Impaired acuity of the approximate number system underlies mathematical learning disability (dyscalculia).

PubMed

Mazzocco, Michèle M M; Feigenson, Lisa; Halberda, Justin

2011-01-01

Many children have significant mathematical learning disabilities (MLD, or dyscalculia) despite adequate schooling. The current study hypothesizes that MLD partly results from a deficiency in the Approximate Number System (ANS) that supports nonverbal numerical representations across species and throughout development. In this study of 71 ninth graders, it is shown that students with MLD have significantly poorer ANS precision than students in all other mathematics achievement groups (low, typically, and high achieving), as measured by psychophysical assessments of ANS acuity (w) and of the mappings between ANS representations and number words (cv). This relation persists even when controlling for domain-general abilities. Furthermore, this ANS precision does not differentiate low-achieving from typically achieving students, suggesting an ANS deficit that is specific to MLD. © 2011 The Authors. Child Development © 2011 Society for Research in Child Development, Inc.

Identifying Subtypes among Children with Developmental Coordination Disorder and Mathematical Learning Disabilities, Using Model-Based Clustering

ERIC Educational Resources Information Center

Pieters, Stefanie; Roeyers, Herbert; Rosseel, Yves; Van Waelvelde, Hilde; Desoete, Annemie

2015-01-01

A relationship between motor and mathematical skills has been shown by previous research. However, the question of whether subtypes can be differentiated within developmental coordination disorder (DCD) and/or mathematical learning disability (MLD) remains unresolved. In a sample of children with and without DCD and/or MLD, a data-driven…

Number Magnitude Processing and Basic Cognitive Functions in Children with Mathematical Learning Disabilities

ERIC Educational Resources Information Center

Andersson, Ulf; Ostergren, Rickard

2012-01-01

The study sought out to extend our knowledge regarding the origin of mathematical learning disabilities (MLD) in children by testing different hypotheses in the same samples of children. Different aspects of cognitive functions and number processing were assessed in fifth- and sixth-graders (11-13 years old) with MLD and compared to controls. The…

Mathematical Learning Disabilities in Children with 22q11.2 Deletion Syndrome: A Review

ERIC Educational Resources Information Center

De Smedt, Bert; Swillen, Ann; Verschaffel, Lieven; Ghesquiere, Pol

2009-01-01

Mathematical learning disabilities (MLD) occur frequently in children with specific genetic disorders, like Turner syndrome, fragile X syndrome and neurofibromatosis. This review focuses on MLD in children with chromosome 22q11.2 deletion syndrome (22q11DS). This syndrome is the most common known microdeletion syndrome with a prevalence of at…

Mathematical learning disabilities and attention deficit and/or hyperactivity disorder: A study of the cognitive processes involved in arithmetic problem solving.

PubMed

Iglesias-Sarmiento, Valentín; Deaño, Manuel; Alfonso, Sonia; Conde, Ángeles

2017-02-01

The purpose of this study was to examine the contribution of cognitive functioning to arithmetic problem solving and to explore the cognitive profiles of children with attention deficit and/or hyperactivity disorder (ADHD) and with mathematical learning disabilities (MLD). The sample was made up of a total of 90 students of 4th, 5th, and 6th grade organized in three: ADHD (n=30), MLD (n=30) and typically achieving control (TA; n=30) group. Assessment was conducted in two sessions in which the PASS processes and arithmetic problem solving were evaluated. The ADHD group's performance in planning and attention was worse than that of the control group. Children with MLD obtained poorer results than the control group in planning and simultaneous and successive processing. Executive processes predicted arithmetic problem solving in the ADHD group whereas simultaneous processing was the unique predictor in the MLD sample. Children with ADHD and with MLD showed characteristic cognitive profiles. Groups' problem-solving performance can be predicted from their cognitive functioning. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mathematics Learning Disability in Girls with Turner Syndrome or Fragile X Syndrome

ERIC Educational Resources Information Center

Murphy, Melissa M.; Mazzocco, Michele M. M.; Gerner, Gwendolyn; Henry, Anne E.

2006-01-01

Two studies were carried out to examine the persistence (Study 1) and characteristics (Study 2) of mathematics learning disability (MLD) in girls with Turner syndrome or fragile X during the primary school years (ages 5-9 years). In Study 1, the rate of MLD for each syndrome group exceeded the rate observed in a grade-matched comparison group,…

Are WISC IQ scores in children with mathematical learning disabilities underestimated? The influence of a specialized intervention on test performance.

PubMed

Lambert, Katharina; Spinath, Birgit

2018-01-01

Intelligence measures play a pivotal role in the diagnosis of mathematical learning disabilities (MLD). Probably as a result of math-related material in IQ tests, children with MLD often display reduced IQ scores. However, it remains unclear whether the effects of math remediation extend to IQ scores. The present study investigated the impact of a special remediation program compared to a control group receiving private tutoring (PT) on the WISC IQ scores of children with MLD. We included N=45 MLD children (7-12 years) in a study with a pre- and post-test control group design. Children received remediation for two years on average. The analyses revealed significantly greater improvements in the experimental group on the Full-Scale IQ, and the Verbal Comprehension, Perceptual Reasoning, and Working Memory indices, but not Processing Speed, compared to the PT group. Children in the experimental group showed an average WISC IQ gain of more than ten points. Results indicate that the WISC IQ scores of MLD children might be underestimated and that an effective math intervention can improve WISC IQ test performance. Taking limitations into account, we discuss the use of IQ measures more generally for defining MLD in research and practice. Copyright © 2017 Elsevier Ltd. All rights reserved.

Selective Spatial Working Memory Impairment in a Group of Children with Mathematics Learning Disabilities and Poor Problem-Solving Skills

ERIC Educational Resources Information Center

Passolunghi, Maria Chiara; Mammarella, Irene Cristina

2012-01-01

This study examines visual and spatial working memory skills in 35 third to fifth graders with both mathematics learning disabilities (MLD) and poor problem-solving skills and 35 of their peers with typical development (TD) on tasks involving both low and high attentional control. Results revealed that children with MLD, relative to TD children,…

An Evolutionary Perspective on Learning Disability in Mathematics

PubMed Central

Geary, David C.

2015-01-01

A distinction between potentially evolved, or biologically-primary forms of cognition, and the culturally-specific, or biologically-secondary forms of cognition that are built from primary systems is used to explore mathematical learning disability (MLD). Using this model, MLD could result from deficits in the brain and cognitive systems that support biologically-primary mathematical competencies, or from the brain and cognitive systems that support the modification of primary systems for the creation of secondary knowledge and secondary cognitive competencies. The former include visuospatial long-term and working memory and the intraparietal sulcus, whereas the latter include the central executive component of working memory and the anterior cingulate cortex and lateral prefrontal cortex. Different forms of MLD are discussed as related to each of the cognitive and brain systems. PMID:17650991

Mathematical (Dis)abilities Within the Opportunity-Propensity Model: The Choice of Math Test Matters

PubMed Central

Baten, Elke; Desoete, Annemie

2018-01-01

This study examined individual differences in mathematics learning by combining antecedent (A), opportunity (O), and propensity (P) indicators within the Opportunity-Propensity Model. Although there is already some evidence for this model based on secondary datasets, there currently is no primary data available that simultaneously takes into account A, O, and P factors in children with and without Mathematical Learning Disabilities (MLD). Therefore, the mathematical abilities of 114 school-aged children (grade 3 till 6) with and without MLD were analyzed and combined with information retrieved from standardized tests and questionnaires. Results indicated significant differences in personality, motivation, temperament, subjective well-being, self-esteem, self-perceived competence, and parental aspirations when comparing children with and without MLD. In addition, A, O, and P factors were found to underlie mathematical abilities and disabilities. For the A factors, parental aspirations explained about half of the variance in fact retrieval speed in children without MLD, and SES was especially involved in the prediction of procedural accuracy in general. Teachers’ experience contributed as O factor and explained about 6% of the variance in mathematical abilities. P indicators explained between 52 and 69% of the variance, with especially intelligence as overall significant predictor. Indirect effects pointed towards the interrelatedness of the predictors and the value of including A, O, and P indicators in a comprehensive model. The role parental aspirations played in fact retrieval speed was partially mediated through the self-perceived competence of the children, whereas the effect of SES on procedural accuracy was partially mediated through intelligence in children of both groups and through working memory capacity in children with MLD. Moreover, in line with the componential structure of mathematics, our findings were dependent on the math task used. Different A, O, and P indicators seemed to be important for fact retrieval speed compared to procedural accuracy. Also, mathematical development type (MLD or typical development) mattered since some A, O, and P factors were predictive for MLD only and the other way around. Practical implications of these findings and recommendations for future research on MLD and on individual differences in mathematical abilities are provided. PMID:29867645

Mathematical (Dis)abilities Within the Opportunity-Propensity Model: The Choice of Math Test Matters.

PubMed

Baten, Elke; Desoete, Annemie

2018-01-01

This study examined individual differences in mathematics learning by combining antecedent (A), opportunity (O), and propensity (P) indicators within the Opportunity-Propensity Model. Although there is already some evidence for this model based on secondary datasets, there currently is no primary data available that simultaneously takes into account A, O, and P factors in children with and without Mathematical Learning Disabilities (MLD). Therefore, the mathematical abilities of 114 school-aged children (grade 3 till 6) with and without MLD were analyzed and combined with information retrieved from standardized tests and questionnaires. Results indicated significant differences in personality, motivation, temperament, subjective well-being, self-esteem, self-perceived competence, and parental aspirations when comparing children with and without MLD. In addition, A, O, and P factors were found to underlie mathematical abilities and disabilities. For the A factors, parental aspirations explained about half of the variance in fact retrieval speed in children without MLD, and SES was especially involved in the prediction of procedural accuracy in general. Teachers' experience contributed as O factor and explained about 6% of the variance in mathematical abilities. P indicators explained between 52 and 69% of the variance, with especially intelligence as overall significant predictor. Indirect effects pointed towards the interrelatedness of the predictors and the value of including A, O, and P indicators in a comprehensive model. The role parental aspirations played in fact retrieval speed was partially mediated through the self-perceived competence of the children, whereas the effect of SES on procedural accuracy was partially mediated through intelligence in children of both groups and through working memory capacity in children with MLD. Moreover, in line with the componential structure of mathematics, our findings were dependent on the math task used. Different A, O, and P indicators seemed to be important for fact retrieval speed compared to procedural accuracy. Also, mathematical development type (MLD or typical development) mattered since some A, O, and P factors were predictive for MLD only and the other way around. Practical implications of these findings and recommendations for future research on MLD and on individual differences in mathematical abilities are provided.

Growth in Rapid Automatized Naming from Grades K to 8 in Children with Math or Reading Disabilities

ERIC Educational Resources Information Center

Mazzocco, Michèle M. M.; Grimm, Kevin J.

2013-01-01

Rapid automatized naming (RAN) is widely used to identify reading disabilities (RD) and has recently been considered a potential predictor of risk for mathematics learning disabilities (MLD). Here we longitudinally examine RAN performance from Grades K to 8, to view how growth on RAN response time differs for children with RD versus MLD. Across…

Neuro-Cognitive Intervention for Working Memory: Preliminary Results and Future Directions.

PubMed

Bree, Kathleen D; Beljan, Paul

2016-01-01

Definitions of working memory identify it as a function of the executive function system in which an individual maintains two or more pieces of information in mind and uses that information simultaneously for some purpose. In academics, working memory is necessary for a variety of functions, including attending to the information one's teacher presents and then using that information simultaneously for problem solving. Research indicates difficulties with working memory are observed in children with mathematics learning disorder (MLD) and reading disorders (RD). To improve working memory and other executive function difficulties, and as an alternative to medication treatments for attention and executive function disorders, the Motor Cognition(2)® (MC(2)®)program was developed. Preliminary research on this program indicates statistically significant improvements in working memory, mathematics, and nonsense word decoding for reading. Further research on the MC(2)® program and its impact on working memory, as well as other areas of executive functioning, is warranted.

Data-driven heterogeneity in mathematical learning disabilities based on the triple code model.

PubMed

Peake, Christian; Jiménez, Juan E; Rodríguez, Cristina

2017-12-01

Many classifications of heterogeneity in mathematical learning disabilities (MLD) have been proposed over the past four decades, however no empirical research has been conducted until recently, and none of the classifications are derived from Triple Code Model (TCM) postulates. The TCM proposes MLD as a heterogeneous disorder, with two distinguishable profiles: a representational subtype and a verbal subtype. A sample of elementary school 3rd to 6th graders was divided into two age cohorts (3rd - 4th grades, and 5th - 6th grades). Using data-driven strategies, based on the cognitive classification variables predicted by the TCM, our sample of children with MLD clustered as expected: a group with representational deficits and a group with number-fact retrieval deficits. In the younger group, a spatial subtype also emerged, while in both cohorts a non-specific cluster was produced whose profile could not be explained by this theoretical approach. Copyright © 2017 Elsevier Ltd. All rights reserved.

The development of product parity sensitivity in children with mathematics learning disability and in typical achievers.

PubMed

Rotem, Avital; Henik, Avishai

2013-02-01

Parity helps us determine whether an arithmetic equation is true or false. The current research examines the development of sensitivity to parity cues in multiplication in typically achieving (TA) children (grades 2, 3, 4 and 6) and in children with mathematics learning disabilities (MLD, grades 6 and 8), via a verification task. In TA children the onset of parity sensitivity was observed at the beginning of 3rd grade, whereas in children with MLD it was documented only in 8th grade. These results suggest that children with MLD develop parity aspects of number sense, though later than TA children. To check the plausibility of equations, children used mainly the multiplication parity rule rather than familiarity with even products. Similar to observations in adults, parity sensitivity was largest for problems with two even operands, moderate for problems with one even and one odd operand, and smallest for problems with two odd operands. Copyright © 2012 Elsevier Ltd. All rights reserved.

Development of Number Line Representations in Children With Mathematical Learning Disability

PubMed Central

Geary, David C.; Hoard, Mary K.; Nugent, Lara; Byrd-Craven, Jennifer

2015-01-01

Children with a mathematical learning disability (MLD, n = 19) and low achieving (LA, n = 43) children were identified using mathematics achievement scores below the 11th percentile and between the 11th and 25th percentiles, respectively. A control group of typically achieving (TA, n = 50) children was also identified. Number line and speed of processing tasks were administered in 1st and 2nd grade and a working memory battery in 1st grade. In both grades, the MLD children were less accurate in their number line placements and more reliant on a natural number-magnitude representational system to make these placements than were TA children. The TA children were more reliant on the school-taught linear system in both grades. The performance of the LA children was similar to that of the MLD children in first grade and to the TA children in second. The central executive component of working memory contributed to across-grade improvements in number line performance and to group differences in this performance. PMID:18473200

Detecting Strengths and Weaknesses in Learning Mathematics through a Model Classifying Mathematical Skills

ERIC Educational Resources Information Center

Karagiannakis, Giannis N.; Baccaglini-Frank, Anna E.; Roussos, Petros

2016-01-01

Through a review of the literature on mathematical learning disabilities (MLD) and low achievement in mathematics (LA) we have proposed a model classifying mathematical skills involved in learning mathematics into four domains (Core number, Memory, Reasoning, and Visual-spatial). In this paper we present a new experimental computer-based battery…

Masking Level Difference Response Norms from Learning Disabled Individuals.

ERIC Educational Resources Information Center

Waryas, Paul A.; Battin, R. Ray

1985-01-01

The study presents normative data on Masking Level Difference (an improvement of the auditory processing of interaural time/intensity differences between signals and masking noises) for 90 learning disabled persons (4-35 years old). It was concluded that the MLD may quickly screen for auditory processing problems. (CL)

Cognitive and Emotional Factors in Children with Mathematical Learning Disabilities

ERIC Educational Resources Information Center

Passolunghi, Maria Chiara

2011-01-01

Emotional and cognitive factors were examined in 18 children with mathematical learning disabilities (MLD), compared with 18 normally achieving children, matched for chronological age, school level, gender and verbal IQ. Working memory, short-term memory, inhibitory processes, speed of processing and level of anxiety in mathematics were assessed…

Nanopatterning of Group V Elements for Tailoring the Electronic Properties of Semiconductors by Monolayer Doping.

PubMed

Thissen, Peter; Cho, Kyeongjae; Longo, Roberto C

2017-01-18

Control of the electronic properties of semiconductors is primarily achieved through doping. While scaling down the device dimensions to the molecular regime presents an increasing number of difficulties, doping control at the nanoscale is still regarded as one of the major challenges of the electronic industry. Within this context, new techniques such as monolayer doping (MLD) represent a substantial improvement toward surface doping with atomic and specific doping dose control at the nanoscale. Our previous work has explained in detail the atomistic mechanism behind MLD by means of density-functional theory calculations (Chem. Mater. 2016, 28, 1975). Here, we address the key questions that will ultimately allow one to optimize the scalability of the MLD process. First, we show that dopant coverage control cannot be achieved by simultaneous reaction of several group V elements, but stepwise reactions make it possible. Second, using ab initio molecular dynamics, we investigate the thermal decomposition of the molecular precursors, together with the stability of the corresponding binary and ternary dopant oxides, prior to the dopant diffusion into the semiconductor surface. Finally, the effect of the coverage and type of dopant on the electronic properties of the semiconductor is also analyzed. Furthermore, the atomistic characterization of the MLD process raises unexpected questions regarding possible crystal damage effects by dopant exchange with the semiconductor ions or the final distribution of the doping impurities within the crystal structure. By combining all our results, optimization recipes to create ultrashallow doped junctions at the nanoscale are finally proposed.

Development of Product Relatedness and Distance Effects in Typical Achievers and in Children With Mathematics Learning Disabilities.

PubMed

Rotem, Avital; Henik, Avishai

2015-01-01

The current study examined the development of two effects that have been found in single-digit multiplication errors: relatedness and distance. Typically achieving (TA) second, fourth, and sixth graders and adults, and sixth and eighth graders with a mathematics learning disability (MLD) performed a verification task. Relatedness was defined by a slow and inaccurate response to false results that were related to one of the operands via a shared multiplication row (e.g., 3 × 4 = 16). Distance was defined by a slow and inaccurate response to false results that were close in magnitude to the true result (e.g., 6 × 8 = 49). The presence of these effects indicates that participants are sensitive to numerical features of products. TA children demonstrated sensitivity to relatedness and distance from second grade onward. With age their sensitivity expanded from easy problems (e.g., 2 × 3) to difficult ones (e.g., 8 × 9). Children with MLD were sensitive to relatedness on easy problems. Their sensitivity to distance differed from the pattern seen in sixth grade and was partial in eighth grade. The presence of numerical sensitivity in children with MLD calls for instructional methods that would further develop their number sense. © Hammill Institute on Disabilities 2014.

Long-term outcomes after allogeneic hematopoietic stem cell transplantation for metachromatic leukodystrophy: the largest single-institution cohort report.

PubMed

Boucher, Alexander A; Miller, Weston; Shanley, Ryan; Ziegler, Richard; Lund, Troy; Raymond, Gerald; Orchard, Paul J

2015-08-07

Metachromatic Leukodystrophy (MLD) is a rare, fatal demyelinating disorder with limited treatment options. Published outcomes after hematopoietic stem cell transplantation (HSCT) are scant and mixed. We report survival and function following HSCT for a large, single-center MLD cohort. Transplant-related data, survival and serial measures (brain MRI, nerve conduction velocity (NCV), neurologic and neuropsychology evaluations) were reviewed. When possible, parental interviews informed current neurologic status, quality-of-life, and adaptive functioning. Gross motor and expressive functions for late-infantile (LI-MLD) and juvenile (J-MLD) patients were described using previously reported, MLD-specific scales. Forty patients with confirmed MLD have undergone HSCT at our center. Twenty-one (53 %) survive at a median 12 years post-HSCT. Most deaths (n = 17) were treatment-related; two died from disease progression. Survival did not depend upon MLD subtype or symptom status at transplant. LI-MLD patients survive beyond reported life expectancy in untreated disease. Abnormal brain MRI and peripheral nerve conduction velocities (NCV) were common before HSCT. Following transplant, fewer patients experienced MRI progression compared to NCV deterioration. Sixteen LI-MLD and J-MLD survivors were evaluable for long-term gross motor and/or expressive language functioning using existing MLD clinical scoring systems. While most J-MLD patients regressed, the aggregate cohort demonstrated superior retention of function compared to published natural history. Seventeen LI-MLD, J-MLD and adult subtype (A-MLD) survivors were evaluable for long-term adaptive functioning, activities of daily living, and/or cognition. Relative cognitive sparing was observed despite overall global decline. Five sibling pairs (one LI-MLD and four J-MLD), in which at least one underwent transplant in our cohort, were evaluable. Within each familial dyad, survival or function was superior for the treated sibling, or if both siblings were transplanted, for the pre-symptomatic sibling. HSCT is a viable treatment option for MLD, but has significant limitations. Later-onset phenotypes may benefit most from early, pre-symptomatic transplant. Until superior, novel treatment strategies are demonstrated, MLD patients should be carefully considered for HSCT.

Cognitive Mechanisms Underlying Achievement Deficits in Children with Mathematical Learning Disability

ERIC Educational Resources Information Center

Geary, David C.; Hoard, Mary K.; Byrd-Craven, Jennifer; Nugent, Lara; Numtee, Chattavee

2007-01-01

Using strict and lenient mathematics achievement cutoff scores to define a learning disability, respective groups of children who are math disabled (MLD, n = 15) and low achieving (LA, n = 44) were identified. These groups and a group of typically achieving (TA, n = 46) children were administered a battery of mathematical cognition, working…

Fact Retrieval Deficits in Low Achieving Children and Children with Mathematical Learning Disability

ERIC Educational Resources Information Center

Geary, David C.; Hoard, Mary K.; Bailey, Drew H.

2012-01-01

Using 4 years of mathematics achievement scores, groups of typically achieving children (n = 101) and low achieving children with mild (LA-mild fact retrieval; n = 97) and severe (LA-severe fact retrieval; n = 18) fact retrieval deficits and mathematically learning disabled children (MLD; n = 15) were identified. Multilevel models contrasted…

The Contributions of Domain-General and Numerical Factors to Third-Grade Arithmetic Skills and Mathematical Learning Disability

ERIC Educational Resources Information Center

Cowan, Richard; Powell, Daisy

2014-01-01

Explanations of the marked individual differences in elementary school mathematical achievement and mathematical learning disability (MLD or dyscalculia) have involved domain-general factors (working memory, reasoning, processing speed, and oral language) and numerical factors that include single-digit processing efficiency and multidigit skills…

Improving the Fraction Word Problem Solving of Students with Mathematics Learning Disabilities: Interactive Computer Application

ERIC Educational Resources Information Center

Shin, Mikyung; Bryant, Diane P.

2017-01-01

Students with mathematics learning disabilities (MLD) have a weak understanding of fraction concepts and skills, which are foundations of algebra. Such students might benefit from computer-assisted instruction that utilizes evidence-based instructional components (cognitive strategies, feedback, virtual manipulatives). As a pilot study using a…

Effects of Two Interventions on Solving Basic Fact Problems by Second Graders with Mathematics Learning Disabilities

ERIC Educational Resources Information Center

Dennis, Minyi Shih; Sorrells, Audrey McCray; Falcomata, Terry S.

2016-01-01

This study used a multiple probe across participants design, replicated across two interventions and counterbalanced across participant groups to examine the effects of number sense intervention and extensive practice intervention on strategy transformation when students with mathematics learning disabilities (MLD) solved basic fact problems. In…

Behind Mathematical Learning Disabilities: What about Visual Perception and Motor Skills?

ERIC Educational Resources Information Center

Pieters, Stefanie; Desoete, Annemie; Roeyers, Herbert; Vanderswalmen, Ruth; Van Waelvelde, Hilde

2012-01-01

In a sample of 39 children with mathematical learning disabilities (MLD) and 106 typically developing controls belonging to three control groups of three different ages, we found that visual perception, motor skills and visual-motor integration explained a substantial proportion of the variance in either number fact retrieval or procedural…

Multilineage dysplasia is associated with a poorer prognosis in patients with de novo acute myeloid leukemia with intermediate-risk cytogenetics and wild-type NPM1.

PubMed

Rozman, María; Navarro, José-Tomás; Arenillas, Leonor; Aventín, Anna; Giménez, Teresa; Alonso, Esther; Perea, Granada; Camós, Mireia; Navarrete, Mayda; Tuset, Esperanza; Florensa, Lourdes; Millá, Fuensanta; Nomdedéu, Josep; de la Banda, Esmeralda; Díaz-Beyá, Marina; Pratcorona, Marta; Garrido, Ana; Navarro, Blanca; Brunet, Salut; Sierra, Jorge; Esteve, Jordi

2014-10-01

Acute myeloid leukemia (AML) with myelodysplasia-related changes is characterized by the presence of multilineage dysplasia (MLD), frequently related to high-risk cytogenetics and poor outcome. However, the presence of MLD does not modify the favorable prognostic impact of NPM1 mutation. The prognosis of patients with AML presenting marked dysplasia lacking high-risk cytogenetics and NPM1 mutation is uncertain. We evaluated the prognostic impact of MLD in 177 patients with intermediate-risk cytogenetics AML (IR-AML) and wild-type NPM1. Patients were categorized as MLD-WHO (WHO myelodysplasia criteria; n = 43, 24 %), MLD-NRW (significant MLD non-reaching WHO criteria; n = 16, 9 %), absent MLD (n = 80, 45 %), or non-evaluable MLD (n = 38, 22 %). No differences concerning the main characteristics were observed between patients with or without MLD. Outcome of patients with MLD-WHO and MLD-NRW was similar, and significantly worse than patients lacking MLD. The presence of MLD (66 vs. 80 %, p = 0.03; HR, 95 % CI = 2.3, 1.08-4.08) and higher leukocyte count at diagnosis was the only variable associated with lower probability of complete remission after frontline therapy. Concerning survival, age and leukocytes showed an independent prognostic value, whereas MLD showed a trend to a negative impact (p = 0.087, HR, 95 % CI = 1.426, 0.95-2.142). Moreover, after excluding patients receiving an allogeneic stem cell transplantation in first CR, MLD was associated with a shorter survival (HR, 95 % CI = 1.599, 1.026-2.492; p = 0.038). In conclusion, MLD identifies a subgroup of patients with poorer outcome among patients with IR-AML and wild-type NPM1.

Development of the Metacognitive Skills of Prediction and Evaluation in Children With or Without Math Disability

PubMed Central

Garrett, Adia J.; Mazzocco, Michèle M. M.; Baker, Linda

2009-01-01

Metacognition refers to knowledge about one’s own cognition. The present study was designed to assess metacognitive skills that either precede or follow task engagement, rather than the processes that occur during a task. Specifically, we examined prediction and evaluation skills among children with (n = 17) or without (n = 179) mathematics learning disability (MLD), from grades 2 to 4. Children were asked to predict which of several math problems they could solve correctly; later, they were asked to solve those problems. They were asked to evaluate whether their solution to each of another set of problems was correct. Children’s ability to evaluate their answers to math problems improved from grade 2 to grade 3, whereas there was no change over time in the children’s ability to predict which problems they could solve correctly. Children with MLD were less accurate than children without MLD in evaluating both their correct and incorrect solutions, and they were less accurate at predicting which problems they could solve correctly. However, children with MLD were as accurate as their peers in correctly predicting that they could not solve specific math problems. The findings have implications for the usefulness of children’s self-review during mathematics problem solving. PMID:20084181

Quantification of sulfatides in dried blood and urine spots from metachromatic leukodystrophy patients by liquid chromatography/electrospray tandem mass spectrometry.

PubMed

Barcenas, Mariana; Suhr, Teryn R; Scott, C Ronald; Turecek, Frantisek; Gelb, Michael H

2014-06-10

Treatments are being developed for metachromatic leukodystrophy (MLD), suggesting the need for eventual newborn screening. Previous studies have shown that sulfatide molecular species are increased in the urine of MLD patients compared to samples from non-MLD individuals, but there is no data using dried blood spots (DBS), the most common sample available for newborn screening laboratories. We used ultra-high performance liquid chromatography/tandem mass spectrometry (UHPLC/MS/MS) to quantify sulfatides in DBS and dried urine spots from 14 MLD patients and 50 non-MLD individuals. Several sulfatide molecular species were increased in dried urine samples from all MLD samples compared to non-MLD samples. Sulfatides, especially low molecular species, were increased in DBS from MLD patients, but the sulfatide levels were relatively low. There was good separation in sulfatide levels between MLD and non-MLD samples when dried urine spots were used, but not with DBS, because DBS from non-MLD individuals have measurable levels of sulfatides. Sulfatide accumulation studies in urine, but not in DBS, emerges as the method of choice if newborn screening is to be proposed for MLD. Copyright © 2013 Elsevier B.V. All rights reserved.

Seasonal variation of the global mixed layer depth: comparison between Argo data and FIO-ESM

NASA Astrophysics Data System (ADS)

Zhang, Yutong; Xu, Haiming; Qiao, Fangli; Dong, Changming

2018-03-01

The present study evaluates a simulation of the global ocean mixed layer depth (MLD) using the First Institute of Oceanography-Earth System Model (FIOESM). The seasonal variation of the global MLD from the FIO-ESM simulation is compared to Argo observational data. The Argo data show that the global ocean MLD has a strong seasonal variation with a deep MLD in winter and a shallow MLD in summer, while the spring and fall seasons act as transitional periods. Overall, the FIO-ESM simulation accurately captures the seasonal variation in MLD in most areas. It exhibits a better performance during summer and fall than during winter and spring. The simulated MLD in the Southern Hemisphere is much closer to observations than that in the Northern Hemisphere. In general, the simulated MLD over the South Atlantic Ocean matches the observation best among the six areas. Additionally, the model slightly underestimates the MLD in parts of the North Atlantic Ocean, and slightly overestimates the MLD over the other ocean basins.

A Review of Mathematical Learning Disabilities in Children with Fragile X Syndrome

ERIC Educational Resources Information Center

Murphy, Melissa M.

2009-01-01

The prevalence rate of mathematical learning disabilities (MLD) among children with fragile X syndrome who do not meet criteria for intellectual and developmental disabilities ([approximately equal to] 50% of female children) exceeds the rate reported in the general population. The purpose of this article is two-fold: (1) to review the findings on…

The Gross Motor Skills of Children with Mild Learning Disabilities

ERIC Educational Resources Information Center

Nonis, Karen P.; Jernice, Tan Sing Yee

2014-01-01

Many international studies have examined the gross motor skills of children studying in special schools while local studies of such nature are limited. This study investigated the gross motor skills of children with Mild Learning Disabilities (MLD; n = 14, M age = 8.93 years, SD = 0.33) with the Test of Gross Motor Development-2 (TGMD-2, Ulrich,…

Development of Product Relatedness and Distance Effects in Typical Achievers and in Children with Mathematics Learning Disabilities

ERIC Educational Resources Information Center

Rotem, Avital; Henik, Avishai

2015-01-01

The current study examined the development of two effects that have been found in single-digit multiplication errors: relatedness and distance. Typically achieving (TA) second, fourth, and sixth graders and adults, and sixth and eighth graders with a mathematics learning disability (MLD) performed a verification task. Relatedness was defined by a…

Learning toward practical head pose estimation

NASA Astrophysics Data System (ADS)

Sang, Gaoli; He, Feixiang; Zhu, Rong; Xuan, Shibin

2017-08-01

Head pose is useful information for many face-related tasks, such as face recognition, behavior analysis, human-computer interfaces, etc. Existing head pose estimation methods usually assume that the face images have been well aligned or that sufficient and precise training data are available. In practical applications, however, these assumptions are very likely to be invalid. This paper first investigates the impact of the failure of these assumptions, i.e., misalignment of face images, uncertainty and undersampling of training data, on head pose estimation accuracy of state-of-the-art methods. A learning-based approach is then designed to enhance the robustness of head pose estimation to these factors. To cope with misalignment, instead of using hand-crafted features, it seeks suitable features by learning from a set of training data with a deep convolutional neural network (DCNN), such that the training data can be best classified into the correct head pose categories. To handle uncertainty and undersampling, it employs multivariate labeling distributions (MLDs) with dense sampling intervals to represent the head pose attributes of face images. The correlation between the features and the dense MLD representations of face images is approximated by a maximum entropy model, whose parameters are optimized on the given training data. To estimate the head pose of a face image, its MLD representation is first computed according to the model based on the features extracted from the image by the trained DCNN, and its head pose is then assumed to be the one corresponding to the peak in its MLD. Evaluation experiments on the Pointing'04, FacePix, Multi-PIE, and CASIA-PEAL databases prove the effectiveness and efficiency of the proposed method.

Electrophysiological Evidence for the Sources of the Masking Level Difference.

PubMed

Fowler, Cynthia G

2017-08-16

The purpose of this review article is to review evidence from auditory evoked potential studies to describe the contributions of the auditory brainstem and cortex to the generation of the masking level difference (MLD). A literature review was performed, focusing on the auditory brainstem, middle, and late latency responses used in protocols similar to those used to generate the behavioral MLD. Temporal coding of the signals necessary for generating the MLD occurs in the auditory periphery and brainstem. Brainstem disorders up to wave III of the auditory brainstem response (ABR) can disrupt the MLD. The full MLD requires input to the generators of the auditory late latency potentials to produce all characteristics of the MLD; these characteristics include threshold differences for various binaural signal and noise conditions. Studies using central auditory lesions are beginning to identify the cortical effects on the MLD. The MLD requires auditory processing from the periphery to cortical areas. A healthy auditory periphery and brainstem codes temporal synchrony, which is essential for the ABR. Threshold differences require engaging cortical function beyond the primary auditory cortex. More studies using cortical lesions and evoked potentials or imaging should clarify the specific cortical areas involved in the MLD.

First-Grade Predictors of Mathematical Learning Disability: A Latent Class Trajectory Analysis

PubMed Central

Geary, David C.; Bailey, Drew H.; Littlefield, Andrew; Wood, Phillip; Hoard, Mary K.; Nugent, Lara

2009-01-01

Kindergarten to 3rd grade mathematics achievement scores from a prospective study of mathematical development were subjected to latent growth trajectory analyses (n = 306). The four corresponding classes included children with mathematical learning disability (MLD, 6% of sample), and low (LA, 50%), typically (TA, 39%) and high (HA, 5%) achieving children. The groups were administered a battery of intelligence (IQ), working memory, and mathematical-cognition measures in 1st grade. The children with MLD had general deficits in working memory and IQ, and potentially more specific deficits on measures of number sense. The LA children did not have working memory or IQ deficits, but showed moderate deficits on these number sense measures and for addition fact retrieval. The distinguishing features of the HA children were a strong visuospatial working memory, a strong number sense, and frequent use of memory-based processes to solve addition problems. Implications for the early identification of children at risk for poor mathematics achievement are discussed. PMID:20046817

Water intake and beverage consumption of pre-schoolers from six European countries and associations with socio-economic status: the ToyBox-study.

PubMed

Pinket, An-Sofie; De Craemer, Marieke; Maes, Lea; De Bourdeaudhuij, Ilse; Cardon, Greet; Androutsos, Odysseas; Koletzko, Berthold; Moreno, Luis; Socha, Piotr; Iotova, Violeta; Manios, Yannis; Van Lippevelde, Wendy

2016-09-01

To study the quantity and quality of water intake from beverages among pre-schoolers and investigate associations with gender and socio-economic status (SES). Kindergarten-based cross-sectional survey within the large-scale European ToyBox-study. A standardized protocol was used and parents/caregivers filled in sociodemographic data and a semi-quantitative FFQ. Kindergartens in six European countries (Belgium, Bulgaria, Germany, Greece, Poland and Spain). European pre-schoolers (aged 3·5-5·5 years) and their parents/caregivers (n 7051). Mean water intake was 1051 ml/d; plain water, 547 ml/d; plain milk, 241 ml/d; other fruit juice, 104 ml/d; pure fruit juice, 59 ml/d; soft drinks, 55 ml/d; tea, 45 ml/d; sugared and chocolate milk, 37 ml/d; smoothies, 15 ml/d; and light soft drinks, 6 ml/d. Boys had a higher water intake than girls due to a higher consumption of plain water, but more importantly to the consumption of beverages of less quality. Lower-SES pre-schoolers scored better on quantity than high-SES pre-schoolers, but as a consequence of consumption of sugared beverages. Nevertheless, the associations differed by country. The water intake from beverages did not meet the European Food Safety Authority standard of 1280 ml/d; especially in Western European countries water intake from beverages was low. The most important water sources were plain water, milk and fruit juices. Interventions aiming at a proper and sufficient water intake should focus on both quantity and quality. Messages about water and water sources should be clear for everyone and interventions should be sufficiently tailored.

Re-examining minimal luminal diameter relocation and quantitative coronary angiography--intravascular ultrasound correlations in stented saphenous vein grafts: methodological insights from the randomised RRISC trial.

PubMed

Semeraro, Oscar; Agostoni, Pierfrancesco; Verheye, Stefan; Van Langenhove, Glenn; Van den Heuvel, Paul; Convens, Carl; Van den Branden, Frank; Bruining, Nico; Vermeersch, Paul

2009-03-01

Angiographic parameters (such as late luminal loss) are common endpoints in drug-eluting stent trials, but their correlation with the neointimal process and their reliability in predicting restenosis are debated. Using quantitative coronary angiography (QCA) data (49 bare metal stent and 44 sirolimus-eluting stent lesions) and intravascular ultrasound (IVUS) data (39 bare metal stent and 34 sirolimus-eluting stent lesions) from the randomised Reduction of Restenosis In Saphenous vein grafts with Cypher stent (RRISC) trial, we analysed the "relocation phenomenon" of QCA-based in-stent minimal luminal diameter (MLD) between post-procedure and follow-up and we correlated QCA-based and IVUS-based restenotic parameters in stented saphenous vein grafts. We expected the presence of MLD relocation for low late loss values, as MLD can "migrate" along the stent if minimal re-narrowing occurs, while we anticipated follow-up MLD to be located close to post-procedural MLD position for higher late loss. QCA-based MLD relocation occurred frequently: the site of MLD shifted from post-procedure to follow-up an "absolute" distance of 5.8 mm [2.5-10.2] and a "relative" value of 29% [10-46]. MLD relocation failed to correlate with in-stent late loss (rho = 0.14 for "absolute" MLD relocation [p = 0.17], and rho=0.03 for "relative" relocation [p = 0.811). Follow-up QCA-based and IVUS-based MLD values well correlated in the overall population (rho = 0.76, p < 0.001), but QCA underestimated MLD on average 0.55 +/- 0.49 mm, and this was mainly evident for lower MLD values. Conversely, the location of QCA-based MLD failed to correlate with the location of IVUS-based MLD (rho = 0.01 for "absolute" values--in mm [p = 0.911, rho = 0.19 for "relative" values--in % [p = 0.111). Overall, the ability of late loss to "predict" IVUS parameters of restenosis (maximum neointimal hyperplasia diameter, neointimal hyperplasia index and maximum neointimal hyperplasia area) was moderate (rho between 0.46 and 0.54 for the 3 IVUS parameters). These findings suggest the need for a critical re-evaluation of angiographic parameters (such as late loss) as endpoints for drug-eluting stent trials and the use of more precise techniques to describe accurately and properly the restenotic process.

Integrating Reform-Oriented Math Instruction in Special Education Settings

ERIC Educational Resources Information Center

Bottge, Brian A.; Rueda, Enrique; LaRoque, Perry T.; Serlin, Ronald C.; Kwon, Jungmin

2007-01-01

This mixed-methods study assessed the effects of Enhanced Anchored Instruction (EAI) on the math performance of adolescents with learning disabilities in math (MLD). A quasi-experimental pretest-posttest control group design with switching replications was used to measure students' computation and problem-solving skills on EAI compared to control…

Evaluation of an automated milk leukocyte differential test and the California Mastitis Test for detecting intramammary infection in early- and late-lactation quarters and cows.

PubMed

Godden, S M; Royster, E; Timmerman, J; Rapnicki, P; Green, H

2017-08-01

Study objectives were to (1) describe the diagnostic test characteristics of an automated milk leukocyte differential (MLD) test and the California Mastitis Test (CMT) to identify intramammary infection (IMI) in early- (EL) and late-lactation (LL) quarters and cows when using 3 different approaches to define IMI from milk culture, and (2) describe the repeatability of MLD test results at both the quarter and cow level. Eighty-six EL and 90 LL Holstein cows were sampled from 3 Midwest herds. Quarter milk samples were collected for a cow-side CMT test, milk culture, and MLD testing. Quarter IMI status was defined by 3 methods: culture of a single milk sample, culture of duplicate samples with parallel interpretation, and culture of duplicate samples with serial interpretation. The MLD testing was completed in duplicate within 8 h of sample collection; MLD results (positive/negative) were reported at each possible threshold setting (1-18 for EL; 1-12 for LL) and CMT results (positive/negative) were reported at each possible cut-points (trace, ≥1, ≥2, or 3). We created 2 × 2 tables to compare MLD and CMT results to milk culture, at both the quarter and cow level, when using each of 3 different definitions of IMI as the referent test. Paired MLD test results were compared with evaluate repeatability. The MLD test showed excellent repeatability. The choice of definition of IMI from milk culture had minor effects on estimates of MLD and CMT test characteristics. For EL samples, when interpreting MLD and CMT results at the quarter level, and regardless of the referent test used, both tests had low sensitivity (MLD = 11.7-39.1%; CMT = 0-52.2%) but good to very good specificity (MLD = 82.1-95.2%; CMT = 68.1-100%), depending on the cut-point used. Sensitivity improved slightly if diagnosis was interpreted at the cow level (MLD = 25.6-56.4%; CMT = 0-72.2%), though specificity generally declined (MLD = 61.8-100%; CMT = 25.0-100%) depending on the cut-point used. For LL samples, when interpreted at the quarter level, both tests had variable sensitivity (MLD = 46.6-84.8%; CMT = 9.6-72.7%) and variable specificity (MLD = 59.2-79.8%; CMT = 52.5-97.3%), depending on the cut-point used. Test sensitivity improved if interpreted at the cow level (MLD = 59.6-86.4%; CMT = 19.1-86.4%), though specificity declined (MLD = 32.4-56.8%; CMT = 14.3-92.3%). Producers considering adopting either test for LL or EL screening programs will need to carefully consider the goals and priorities of the program (e.g., whether to prioritize test sensitivity or specificity) when deciding on the level of interpretation (quarter or cow) and when selecting the optimal cut-point for interpreting test results. Additional validation studies and large randomized field studies will be needed to evaluate the effect of adopting either test in selective dry cow therapy or fresh cow screening programs on udder health, antibiotic use, and economics. The Authors. Published by the Federation of Animal Science Societies and Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).

Using milk leukocyte differentials for diagnosis of subclinical bovine mastitis.

PubMed

Gonçalves, Juliano Leonel; Lyman, Roberta L; Hockett, Mitchell; Rodriguez, Rudy; Dos Santos, Marcos Veiga; Anderson, Kevin L

2017-08-01

This research study aimed to evaluate the use of the milk leukocyte differential (MLD) to: (a) identify quarter milks that are culture-positive; and (b) characterize the milk leukocyte responses to specific groups of pathogens causing subclinical mastitis. The MLD measures the absolute number and relative percentage of inflammatory cells in milk samples. Using the MLD in two dairy herds (170 and 172 lactating cows, respectively), we studied all lactating cows with a most recent monthly Dairy Herd Improvement Association somatic cell count (SCC) >200 × 103 cells/ml. Quarter milk samples from 78 cows meeting study criteria were analysed by MLD and aseptically collected milk samples were subjected to microbiological culture (MC). Based upon automated instrument evaluation of the number and percentage of inflammatory cells in milk, samples were designated as either MLD-positive or - negative for subclinicial mastitis. Positive MC were obtained from 102/156 (65·4%) of MLD-positive milk samples, and 28/135 (20·7%) of MLD-negative milk samples were MC-positive. When MC was considered the gold standard for mastitis diagnosis, the calculated diagnostic Se of the MLD was 65·4% (IC95% = 57·4 to 72·8%) and the Sp was 79·3% (IC95% = 71·4 to 85·7%). Quarter milks positive on MC had higher absolute numbers of neutrophils, lymphocytes and macrophages, with higher neutrophils% and lymphocytes% but lower macrophages%. The Log10 (N/L) ratios were the most useful ratio to differentiate specific subclinical mastitis quarters from healthy quarters. Use of the MLD on cows with monthly composite SCC > 200 × 103 cells/ml for screening at quarter level identified quarters more likely to be culture-positive. In conclusion, the MLD can provide an analysis of mammary quarter status more detailed than provided by SCC alone; however, the MLD response to subclinical mastitis was not found useful to specifically identify the causative pathogen.

Cognitive Processing and Mathematical Achievement: A Study with Schoolchildren between Fourth and Sixth Grade of Primary Education

ERIC Educational Resources Information Center

Iglesias-Sarmiento, Valentin; Deano, Manuel

2011-01-01

This investigation analyzed the relation between cognitive functioning and mathematical achievement in 114 students in fourth, fifth, and sixth grades. Differences in cognitive performance were studied concurrently in three selected achievement groups: mathematical learning disability group (MLD), low achieving group (LA), and typically achieving…

Defining the ecologically relevant mixed-layer depth for Antarctica's coastal seas

NASA Astrophysics Data System (ADS)

Carvalho, Filipa; Kohut, Josh; Oliver, Matthew J.; Schofield, Oscar

2017-01-01

Mixed-layer depth (MLD) has been widely linked to phytoplankton dynamics in Antarctica's coastal regions; however, inconsistent definitions have made intercomparisons among region-specific studies difficult. Using a data set with over 20,000 water column profiles corresponding to 32 Slocum glider deployments in three coastal Antarctic regions (Ross Sea, Amundsen Sea, and West Antarctic Peninsula), we evaluated the relationship between MLD and phytoplankton vertical distribution. Comparisons of these MLD estimates to an applied definition of phytoplankton bloom depth, as defined by the deepest inflection point in the chlorophyll profile, show that the maximum of buoyancy frequency is a good proxy for an ecologically relevant MLD. A quality index is used to filter profiles where MLD is not determined. Despite the different regional physical settings, we found that the MLD definition based on the maximum of buoyancy frequency best describes the depth to which phytoplankton can be mixed in Antarctica's coastal seas.

Effect of Normal Lung Definition on Lung Dosimetry and Lung Toxicity Prediction in Radiation Therapy Treatment Planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Weili; Department of Radiation Oncology, the Fourth Affiliated Hospital, China Medical University, Shenyang; Xu, Yaping

2013-08-01

Purpose: This study aimed to compare lung dose–volume histogram (DVH) parameters such as mean lung dose (MLD) and the lung volume receiving ≥20 Gy (V20) of commonly used definitions of normal lung in terms of tumor/target subtraction and to determine to what extent they differ in predicting radiation pneumonitis (RP). Methods and Materials: One hundred lung cancer patients treated with definitive radiation therapy were assessed. The gross tumor volume (GTV) and clinical planning target volume (PTV{sub c}) were defined by the treating physician and dosimetrist. For this study, the clinical target volume (CTV) was defined as GTV with 8-mm uniformmore » expansion, and the PTV was defined as CTV with an 8-mm uniform expansion. Lung DVHs were generated with exclusion of targets: (1) GTV (DVH{sub G}); (2) CTV (DVH{sub C}); (3) PTV (DVH{sub P}); and (4) PTV{sub c} (DVH{sub Pc}). The lung DVHs, V20s, and MLDs from each of the 4 methods were compared, as was their significance in predicting radiation pneumonitis of grade 2 or greater (RP2). Results: There are significant differences in dosimetric parameters among the various definition methods (all Ps<.05). The mean and maximum differences in V20 are 4.4% and 12.6% (95% confidence interval 3.6%-5.1%), respectively. The mean and maximum differences in MLD are 3.3 Gy and 7.5 Gy (95% confidence interval, 1.7-4.8 Gy), respectively. MLDs of all methods are highly correlated with each other and significantly correlated with clinical RP2, although V20s are not. For RP2 prediction, on the receiver operating characteristic curve, MLD from DVH{sub G} (MLD{sub G}) has a greater area under curve of than MLD from DVH{sub C} (MLD{sub C}) or DVH{sub P} (MLD{sub P}). Limiting RP2 to 30%, the threshold is 22.4, 20.6, and 18.8 Gy, for MLD{sub G}, MLD{sub C}, and MLD{sub P}, respectively. Conclusions: The differences in MLD and V20 from various lung definitions are significant. MLD from the GTV exclusion method may be more accurate in predicting clinical significant radiation pneumonitis.« less

[Total drinking water intake and sources of children and adolescent in one district of Shenzhen].

PubMed

Du, Songming; Hu, Xiaoqi; Zhang, Qian; Wang, Xiaojun; Liu, Ailing; Pan, Hui; He, Shuang; Ma, Guansheng

2013-05-01

To describe total drinking water intake among primary and middle school students in one district of Shenzhen and to provide scientific evidence for adequate intakes of drinking water for different people in China. A total of 816 students from three primary and middle schools of Shenzhen was selected using three-stage random sampling method. The information on amounts and types of daily drinking water was recorded by subjects for seven consecutive days using a 24 hours measurement. The amounts and types of daily drinking water among different ages and between boys and girls were analyzed. The average total drinking water of subjects was (1225+/-557) ml/d, and the consumption of total drinking water in boys ((1303+/-639) ml/d) was significantly higher than that in girls ((1134+/-478) ml/d, P<0.01). The consumption of total drinking water of secondary school students ((1389+/-541) ml/d) and high school student ((1318+/-641) ml/d) was no statistically difference, but was higher than primary school students ((1097+/-525) ml/d, P<0.01). The average plain water and beverages of the subjects was (818+/-541) ml/d and (407+/-294) ml/d respectively. Major of fluid intake comes from drinking water in children and adolescenct of Shenzhen. The knowledge of drinking water of primary school students is need to comprehensive enough.

Molecular Layer Deposition for Surface Modification of Lithium-Ion Battery Electrodes

DOE PAGES

Ban, Chunmei; George, Steven M.

2016-10-21

This review presents the MLD process and its outstanding attributes for electrochemical applications and is inspired by recent successes in applying molecular layer deposition (MLD) to stabilize lithium-ion (Li-ion) electrodes. Furthermore, this review discusses various MLD materials and their implementation in Li-ion electrodes. The rationale behind these emerging uses of MLD is examined to motivate future efforts on the fundamental understanding of interphase chemistry and the development of new materials for enhanced electrochemical performance.

Innovative Leaders Take the Phone and Run: Profiles of Four Trailblazing Programs

ERIC Educational Resources Information Center

Norris, Cathleen; Soloway, Elliot; Menchhofer, Kyle; Bauman, Billie Diane; Dickerson, Mindy; Schad, Lenny; Tomko, Sue

2010-01-01

While the Internet changed everything, mobile will change everything squared. The Internet is just a roadway, and computers--the equivalent of cars for the Internet--have been expensive. The keepers of the information roadway--the telecommunication companies--will give one a "computer," such as cell phone, mobile learning device, or MLD,…

Master Logic Diagram: method for hazard and initiating event identification in process plants.

PubMed

Papazoglou, I A; Aneziris, O N

2003-02-28

Master Logic Diagram (MLD), a method for identifying events initiating accidents in chemical installations, is presented. MLD is a logic diagram that resembles a fault tree but without the formal mathematical properties of the latter. MLD starts with a Top Event "Loss of Containment" and decomposes it into simpler contributing events. A generic MLD has been developed which may be applied to all chemical installations storing toxic and/or flammable substances. The method is exemplified through its application to an ammonia storage facility.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berger, J.; Loeschl, B.; Bernheimer, H.

Occurrence, distribution, and phenotype of arylsulfatase A (ASA) mutations were investigated in 27 patients with metachromatic leukodystrophy (MLD) from Central Europe, mainly from Austria (n = 15) and Poland (n = 9). Genomic DNA from leukocytes, fibroblasts, or paraffin-embedded, formalin-fixed brain or nerve tissue, respectively, was tested by natural or mutated primer-modulated PCR restriction fragment length polymorphism for the eight most common European mutations: R84Q, S96F, 459+1G>A, I179S, A212V, 1204+1G>A, P426L, and 1401del11bp. The overall identification rate of unrelated MLD alleles was the highest in adult (90%), medium in juvenile (50%), and lowest in late infantile (36%) MLD patients. Themore » two common alleles, 459+1G>A and P426L, together accounted for 42% of all 50 unrelated MLD alleles investigated; I179S was observed in 6 of 50 MLD alleles (12%). Thus, I179S was far more frequent than hitherto thought and appears to be a third common mutation in Europe. Moreover, a different allelic distribution between Austrian and Polish juvenile patients was disclosed, indicating genetic heterogeneity of MLD even within Central Europe. The genotype-phenotype correlation suggested by Polten et al. was not followed by all of our MLD patients. Moreover, some MLD patients with identical ASA mutations presented with different phenotypes. This may be due, at least in some cases, to the presence of an additional mutation on individual mutant alleles. Therefore, prediction of the clinical course from single mutation analysis is not possible. 28 refs.« less

Mathematics Deficiencies in Children with Very Low Birth Weight or Very Preterm Birth

ERIC Educational Resources Information Center

Taylor, H. Gerry; Espy, Kimberly Andrews; Anderson, Peter J.

2009-01-01

Children with very low birth weight (VLBW, less than 1500 g) or very preterm birth (VPTB, less than 32 weeks gestational age or GA) have more mathematics disabilities or deficiencies (MD) and higher rates of mathematics learning disabilities (MLD) than normal birth weight term-born children (NBW, greater than 2500 g and greater than 36 weeks GA).…

Manual Lymphatic Drainage and Active Exercise Effects on Lymphatic Function Do Not Translate Into Morbidities in Women Who Underwent Breast Cancer Surgery.

PubMed

Freire de Oliveira, Mariana Maia; Costa Gurgel, Maria Salete; Pace do Amaral, Maria Teresa; Amorim, Bárbara Juarez; Ramos, Celso Darío; Almeida Filho, José Geraldo; de Rezende, Laura Ferreira; Zanatta Sarian, Luís Otávio

2017-02-01

To evaluate manual lymphatic drainage (MLD) and active exercise effects on lymphatic alterations of the upper limb (UL), range of motion (ROM) of shoulder, and scar complications after breast cancer surgery. Clinical trial. Health care center. Women (N=105) undergoing radical breast cancer surgery who were matched for staging, age, and body mass index. Women (n=52) were submitted to MLD and 53 to active exercises for UL for 1 month and followed up. Shoulder ROM, surgical wound inspection and palpation, UL circumference measurements, and lymphoscintigraphy were performed in preoperative and postoperative periods. There was no significant difference between groups with regard to wound healing complications, ROM, and UL circumferences. After surgery, 25 (48.1%) of the MLD group and 19 (35.8%) of the active exercise group showed worsening in radiopharmaceutical uptake velocity, whereas 9 (17.3%) of the MLD group and 11 (20.8%) of the active exercise group showed improved velocity (P=.445). With regard to uptake intensity, 27 (51.9%) of the MLD group and 21 (39.6%) of the active exercise group showed worsening whereas 7 (13.5%) of the MLD group and 7 (13.2%) of the active exercise group showed some improvement (P=.391). The presence of collateral circulation was similar in both groups at both time points evaluated. The active exercise group had a significant increase in postoperative liver absorption (P=.005), and the MLD group had a significant increase in postoperative dermal backflow (P=.024). MLD and active exercise effects are equivalent with regard to morbidity. Minor changes in lymphatic function associated with either MLD or active exercises were not related to patients' symptoms or signs. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Spatial localization of the Ebola virus glycoprotein mucin-like domain determined by cryo-electron tomography.

PubMed

Tran, Erin E H; Simmons, James A; Bartesaghi, Alberto; Shoemaker, Charles J; Nelson, Elizabeth; White, Judith M; Subramaniam, Sriram

2014-09-01

The Ebola virus glycoprotein mucin-like domain (MLD) is implicated in Ebola virus cell entry and immune evasion. Using cryo-electron tomography of Ebola virus-like particles, we determined a three-dimensional structure for the full-length glycoprotein in a near-native state and compared it to that of a glycoprotein lacking the MLD. Our results, which show that the MLD is located at the apex and the sides of each glycoprotein monomer, provide a structural template for analysis of MLD function. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Gallbladder Polyps in Metachromatic Leukodystrophy.

PubMed

Almarzooqi, Saeeda; Quadri, Asif; Albawardi, Alia

2018-04-01

Metachromatic leukodystrophy (MLD) is an autosomal recessive lysosomal storage disease, caused by a deficiency of arylsulfatase A, and leads to demyelination of the nervous system. A putative association between MLD and gallbladder pathology including malignancy is documented in the medical literature. A 10-year-old boy with MLD was found to have a papillary growth within a cystically dilated gallbladder. The lesion was confirmed to be papillomatosis/polyp with focal intestinal metaplasia. Dysplasia was not identified. MLD may be associated with a spectrum of gallbladder pathology including neoplastic conditions. Pathologists and clinicians should be aware of this association/risk. The patient may be offered regular ultrasound screening of the gallbladder.

Characterization of nano-porosity in molecular layer deposited films.

PubMed

Perrotta, Alberto; Poodt, Paul; van den Bruele, F J Fieke; Kessels, W M M Erwin; Creatore, Mariadriana

2018-06-12

Molecular layer deposition (MLD) delivers (ultra-) thin organic and hybrid materials, with atomic-level thickness control. However, such layers are often reported to be unstable under ambient conditions, due to the interaction of water and oxygen with the hybrid structure, consequently limiting their applications. In this contribution, we investigate the impact of porosity in MLD layers on their degradation. Alucone layers were deposited by means of trimethylaluminium and ethylene glycol, adopting both temporal and spatial MLD and characterized by means of FT-IR spectroscopy, spectroscopic ellipsometry, and ellipsometric porosimetry. The highest growth per cycle (GPC) achieved by spatial MLD resulted in alucone layers with very low stability in ambient air, leading to their conversion to AlOx. Alucones deposited by means of temporal MLD, instead, showed a lower GPC and a higher ambient stability. Ellipsometric porosimetry showed the presence of open nano-porosity in pristine alucone layers. Pores with a diameter in the range of 0.42-2 nm were probed, with a relative content between 1.5% and 5%, respectively, which are attributed to the temporal and spatial MLD layers. We concluded that a correlation exists between the process GPC, the open-porosity relative content, and the degradation of alucone layers.

Number Line Estimation: The Use of Number Line Magnitude Estimation to Detect the Presence of Math Disability in Postsecondary Students

ERIC Educational Resources Information Center

McDonald, Steven A.

2010-01-01

This study arose from an interest in the possible presence of mathematics disabilities among students enrolled in the developmental math program at a large university in the Mid-Atlantic region. Research in mathematics learning disabilities (MLD) has included a focus on the construct of working memory and number sense. A component of number sense…

Combining Manual Lymph Drainage with Physical Exercise after Modified Radical Mastectomy Effectively Prevents Upper Limb Lymphedema.

PubMed

Zhang, Lijuan; Fan, Aiqun; Yan, Jun; He, Yan; Zhang, Huiting; Zhang, Huizhen; Zhong, Qiaoling; Liu, Feng; Luo, Qinghua; Zhang, Liping; Tang, Hailin; Xin, Mingzhu

2016-06-01

Upper limb lymphedema is a common complication after radical mastectomy in patients with breast cancer. In this study, we examined the efficacy of self-manual lymph drainage (MLD) after modified radical mastectomy for the prevention of upper limb lymphedema, scar formation, or shoulder joint dysfunction in breast cancer patients. Breast cancer patients scheduled for modified radical mastectomy were randomly apportioned to undergo physical exercise only (PE group, the control; n = 500) or self-MLD as well as exercise (MLD group; n = 500) after surgery. In the PE group, patients started to undertake remedial exercises and progressive weight training after recovery from anesthesia. In the MLD group, in addition to receiving the same treatments as in the PE group, the patients were trained to perform self-MLD on the surgical incision for 10 min/session, 3 sessions/day, beginning after suture removal and incision closure (10 to 30 days after the surgery). Scar formation was evaluated at one week, and 1, 3, 6, and 12 months after the surgery, respectively. Upper limb circumference and shoulder abduction were measured 24 h before surgery, and at one week, and 1, 3, 6 and 12 months after the surgery. Compared to those in the PE group, patients in MLD group experienced significant improvements in scar contracture, shoulder abduction, and upper limb circumference. Self-MLD, in combination with physical exercise, is beneficial for breast cancer patients in preventing postmastectomy scar formation, upper limb lymphedema, and shoulder joint dysfunction.

Randomized trial investigating the efficacy of manual lymphatic drainage to improve early outcome after total knee arthroplasty.

PubMed

Ebert, Jay R; Joss, Brendan; Jardine, Berit; Wood, David J

2013-11-01

To investigate the efficacy of manual lymphatic drainage (MLD) in the early postoperative period after total knee arthroplasty (TKA) to reduce edema and pain and improve knee range of motion. Prospective randomized controlled trial. Private hospital and functional rehabilitation clinic. Consecutive sample of patients (N=43; 53 knees) scheduled for TKA. MLD (vs no MLD) on days 2, 3, and 4 postoperatively. Both groups underwent conventional, concomitant physical therapy. Clinical assessment was undertaken pre- and postoperatively prior to and after the designated postoperative MLD sessions (days 2, 3, and 4) and at 6 weeks postsurgery. This included active knee flexion and extension range of motion, lower limb girths (ankle, midpatella, thigh, and calf), and knee pain using a numeric rating scale and the Knee Injury and Osteoarthritis Outcome Score. A significant group effect was observed for active knee flexion, with post hoc tests demonstrating a significantly greater active knee flexion in the MLD group when compared with the control (no MLD) group at the final measure prior to hospital discharge (day 4 postsurgery) and at 6 weeks postsurgery. There were no further group effects observed for the remaining patient-reported and functional outcomes. MLD in the early postoperative stages after TKA appears to improve active knee flexion up to 6 weeks postsurgery, in addition to conventional care. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Extended GTST-MLD for aerospace system safety analysis.

PubMed

Guo, Chiming; Gong, Shiyu; Tan, Lin; Guo, Bo

2012-06-01

The hazards caused by complex interactions in the aerospace system have become a problem that urgently needs to be settled. This article introduces a method for aerospace system hazard interaction identification based on extended GTST-MLD (goal tree-success tree-master logic diagram) during the design stage. GTST-MLD is a functional modeling framework with a simple architecture. Ontology is used to extend the ability of system interaction description in GTST-MLD by adding the system design knowledge and the past accident experience. From the level of functionality and equipment, respectively, this approach can help the technician detect potential hazard interactions. Finally, a case is used to show the method. © 2011 Society for Risk Analysis.

Functionalization of SiO2 Surfaces for Si Monolayer Doping with Minimal Carbon Contamination.

PubMed

van Druenen, Maart; Collins, Gillian; Glynn, Colm; O'Dwyer, Colm; Holmes, Justin D

2018-01-17

Monolayer doping (MLD) involves the functionalization of semiconductor surfaces followed by an annealing step to diffuse the dopant into the substrate. We report an alternative doping method, oxide-MLD, where ultrathin SiO 2 overlayers are functionalized with phosphonic acids for doping Si. Similar peak carrier concentrations were achieved when compared with hydrosilylated surfaces (∼2 × 10 20 atoms/cm 3 ). Oxide-MLD offers several advantages over conventional MLD, such as ease of sample processing, superior ambient stability, and minimal carbon contamination. The incorporation of an oxide layer minimizes carbon contamination by facilitating attachment of carbon-free precursors or by impeding carbon diffusion. The oxide-MLD strategy allows selection of many inexpensive precursors and therefore allows application to both p- and n-doping. The phosphonic acid-functionalized SiO 2 surfaces were investigated using X-ray photoelectron spectroscopy and attenuated total reflectance Fourier transform infrared spectroscopy, whereas doping was assessed using electrochemical capacitance voltage and Hall measurements.

Mixed and mixing layer depths in the ocean surface boundary layer under conditions of diurnal stratification

NASA Astrophysics Data System (ADS)

Sutherland, G.; Reverdin, G.; Marié, L.; Ward, B.

2014-12-01

A comparison between mixed (MLD) and mixing (XLD) layer depths is presented from the SubTRopical Atlantic Surface Salinity Experiment (STRASSE) cruise in the subtropical Atlantic. This study consists of 400 microstructure profiles during fairly calm and moderate conditions (2 < U10 < 10 m s-1) and strong solar heating O(1000 W m-2). The XLD is determined from a decrease in the turbulent dissipation rate to an assumed background level. Two different thresholds for the background dissipation level are tested, 10-8 and 10-9 m2 s-3, and these are compared with the MLD as calculated using a density threshold. The larger background threshold agrees with the MLD during restratification but only extends to half the MLD during nighttime convection, while the lesser threshold agrees well during convection but is deeper by a factor of 2 during restratification. Observations suggest the use of a larger density threshold to determine the MLD in a buoyancy driven regime.

Real-time handling of existing content sources on a multi-layer display

NASA Astrophysics Data System (ADS)

Singh, Darryl S. K.; Shin, Jung

2013-03-01

A Multi-Layer Display (MLD) consists of two or more imaging planes separated by physical depth where the depth is a key component in creating a glasses-free 3D effect. Its core benefits include being viewable from multiple angles, having full panel resolution for 3D effects with no side effects of nausea or eye-strain. However, typically content must be designed for its optical configuration in foreground and background image pairs. A process was designed to give a consistent 3D effect in a 2-layer MLD from existing stereo video content in real-time. Optimizations to stereo matching algorithms that generate depth maps in real-time were specifically tailored for the optical characteristics and image processing algorithms of a MLD. The end-to-end process included improvements to the Hierarchical Belief Propagation (HBP) stereo matching algorithm, improvements to optical flow and temporal consistency. Imaging algorithms designed for the optical characteristics of a MLD provided some visual compensation for depth map inaccuracies. The result can be demonstrated in a PC environment, displayed on a 22" MLD, used in the casino slot market, with 8mm of panel seperation. Prior to this development, stereo content had not been used to achieve a depth-based 3D effect on a MLD in real-time

Effects of lymphatic drainage and local cryo exposition regeneration after high-intensive exercises

PubMed Central

Behringer, Michael; Jedlicka, Diana; McCourt, Molly; Ring, Matthias; Mester, Joachim

2016-01-01

Summary Background Recovery from exercise and competition is important in sports medicine, particularly when rest periods are short. The objective is to determine the efficacy of cryo exposition (CRY) and manual lymphatic drainage (MLD) to hasten short term recovery of muscle performance after eccentric contractions. Methods In a randomized controlled trial, 30 healthy sport students (21 males, 9 females; age: 25.7±2.8 years) performed 4×20 eccentric contractions of knee extensors, followed by 30 min MLD, CRY, or rest (RST) under controlled laboratory environment. Maximal voluntary contractions (MVC), electrically induced muscle fatigue (FI), and electrically induced tetani (EIT) at low (T2: 20 Hz) and high frequencies were tested. Results Force decline and recovery kinetics regarding MVC, FI, and EIT did not differ significantly (p<0.05) between groups. That is, 24 h after the intervention, MVC (MLD: 80.9±5.5%; CRY: 81.1±8.5%; RST: 83.5±7.3%), FI (MLD: 83.2±23.7%; CRY: 81.2±38.8%; RST: 93.2±22.9%), and EIT (T1: MLD: 53.0±29.5%; CRY: 39.0±32.9%; RST: 46.3±26.1%; T2: MLD: 84.2±27.2%; CRY: 64.2±24.2%; RST: 66.6±22.3%) were similarly depressed irrespective of applied treatments. Conclusion Neither CRY nor MLD hastened the recovery of muscle performance, when applied for 30 min. Identification number of the Primary Registry Network: DRKS00007608. PMID:27900297

Venous flow during manual lymphatic drainage applied to different regions of the lower extremity in people with and without chronic venous insufficiency: a cross-sectional study.

PubMed

Crisóstomo, R S S; Candeias, M S; Armada-da-Silva, P A S

2017-03-01

To evaluate the effect of manual lymphatic drainage (MLD) on venous flow when applied to the medial and lateral aspects of the thigh and leg in patients with chronic venous insufficiency (CVI) and healthy subjects. Cross-sectional study. Participants were assessed in a school-based health community attendant service. Fifty-seven subjects participated in this study {mean age: 43 [standard deviation (SD) 14] years, 38 women and 19 men}. Of these, 28 subjects had CVI [mean age 47 (SD 12) years] and 29 subjects did not have CVI [mean age 39 (14) years]. MLD was applied by a certificated physical therapist to the medial and lateral aspects of the thigh and leg. Cross-sectional area; blood flow velocities in the femoral vein, great saphenous vein, popliteal vein and small saphenous vein at baseline and during MLD, measured by duplex ultrasound. Flow volume in the femoral vein increased from baseline [5.19 (SD 3.25)cm 3 /second] when MLD was applied to the medial [7.03 (SD 3.65)cm 3 /second; P≤0.001; mean difference -1.69; 95% confidence interval (CI) -2.42 to -0.97] and lateral [6.16 (SD 3.35)cm 3 /second; P≤0.001; mean difference -1.04; 95% CI -1.70 to -0.39] aspects of the thigh. Venous flow augmentation in the femoral vein and great saphenous vein was higher when MLD was applied to the medial aspect of the thigh (P<0.001), while MLD had a similar effect on venous blood flow regardless of whether it was applied to the medial or the lateral aspect of the leg (P=0.731). MLD increases blood flow in deep and superficial veins. MLD should be applied along the route of the venous vessels for improved venous return. Copyright © 2016 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

[Low dose volume histogram analysis of the lungs in prediction of acute radiation pneumonitis in patients with esophageal cancer treated with three-dimensional conformal radiotherapy].

PubMed

Shen, Wen-bin; Zhu, Shu-chai; Gao, Hong-mei; Li, You-mei; Liu, Zhi-kun; Li, Juan; Su, Jing-wei; Wan, Jun

2013-01-01

To investigate the predictive value of low dose volume of the lung on acute radiation pneumonitis (RP) in patients with esophageal cancer treated with three-dimensional conformal radiotherapy (3D-CRT) only, and to analyze the relation of comprehensive parameters of the dose-volume V5, V20 and mean lung dose (MLD) with acute RP. Two hundred and twenty-two patients with esophageal cancer treated by 3D-CRT have been followed up. The V5-V30 and MLD were calculated from the dose-volume histogram system. The clinical factors and treatment parameters were collected and analyzed. The acute RP was evaluated according to the RTOG toxicity criteria. The acute RP of grade 1, 2, 3 and 4 were observed in 68 (30.6%), 40 (18.0%), 8 (3.6%) and 1 (0.5%) cases, respectively. The univariate analysis of measurement data:The primary tumor length, radiation fields, MLD and lung V5-V30 had a significant relationship with the acute RP. The magnitude of the number of radiation fields, the volume of GTV, MLD and Lung V5-V30 had a significant difference in whether the ≥ grade 1 and ≥ grade 2 acute RP developed or not. Binary logistic regression analysis showed that MLD, Lung V5, V20 and V25 were independent risk factors of ≥ grade 1 acute RP, and the radiation fields, MLD and Lung V5 were independent risk factors of ≥ grade 2 acute RP. The ≥ grade 1 and ≥ grade 2 acute RP were significantly decreased when MLD less than 14 Gy, V5 and V20 were less than 60% and 28%,respectively. When the V20 ≤ 28%, the acute RP was significantly decreased in V5 ≤ 60% group. When the MLD was ≤ 14 Gy, the ≥ 1 grade acute RP was significantly decreased in the V5 ≤ 60% group. When the MLD was >14 Gy, the ≥ grade 2 acute RP was significantly decreased in the V5 ≤ 60% group. The low dose volume of the lung is effective in predicting radiation pneumonitis in patients with esophageal cancer treated with 3D-CRT only. The comprehensive parameters combined with V5, V20 and MLD may increase the effect in predicting radiation pneumonitis.

Modified lingguizhugan decoction incorporated with dietary restriction and exercise ameliorates hyperglycemia, hyperlipidemia and hypertension in a rat model of the metabolic syndrome.

PubMed

Yao, Limei; Wei, Jingjing; Shi, Si; Guo, Kunbin; Wang, Xiangyu; Wang, Qi; Chen, Dingsheng; Li, Weirong

2017-02-28

Modified Lingguizhugan Decoction (MLD) came from famous Chinese medicine Linggui Zhugan Decoction. The MLD is used for the treatment of metabolic syndrome in the clinical setting. Our study focuses on the comprehensive treatment of MLD incorporated with dietary restriction and exercise in a rat model of the metabolic syndrome (MS). Rats were divided into five groups: control group (Cont), high-fat diet group (HFD), high-fat diet incorporated with dietary restriction group (HFD-DR), exercise incorporated with dietary restriction group (HFD-DR-Ex) and MLD incorporated with dietary restriction and exercise group (HFD-DR-Ex-MLD). Treatments were conducted for 1 week after feeding high-fat diet for 12 weeks. The effects of treatments on high fat diet-induced obesity, hyperglycemia, hyperlipidemia, hypertension, hepatic injury and insulin resistance in rats of MS were examined. In addition, the tumor necrosis factor-α (TNF-α), leptin and protein kinase B (PKB) in rats serum and liver were also examined by enzyme-linked immunosorbent assay (ELISA). After a week's intervention by dietary restriction, dietary restriction incorporated with exercise or MLD, compared with HFD rats, the relative weight of liver and fat, levels of triglyceride, total cholesterol, low-density lipoprotein, free fatty acid, aspartate aminotransferase, glutamic-pyruvic transaminase and alkaline phosphatase, insulin, were significantly decreased (p < 0.05 or 0.01). This treatment also inhibited abnormal increases of TNF-α, leptin and PKB in serum and liver. MLD incorporated with dietary restriction and exercise treatment exhibit effects in alleviating high-fat diet-induced obesity, hyperglycemia, hyperlipidemia, hypertension, hepatic injury and insulin resistance, which are possibly due to the down-regulation of TNF-α, leptin and PKB.

Effect of Manual Lymphatic Drainage After Total Knee Arthroplasty: A Randomized Controlled Trial.

PubMed

Pichonnaz, Claude; Bassin, Jean-Philippe; Lécureux, Estelle; Christe, Guillaume; Currat, Damien; Aminian, Kamiar; Jolles, Brigitte M

2016-05-01

To evaluate the effects of manual lymphatic drainage (MLD) on knee swelling and the assumed consequences of swelling after total knee arthroplasty (TKA). Randomized controlled trial. Primary care hospital. Two groups of 30 patients were randomized before TKA surgery (N=60; 65% women [39]; mean age, 70.7±8.8y; weight, 77.8±11.3kg; size, 1.64±0.08m; body mass index, 29.9±4.1kg/m(2)). Participants received either 5 MLD treatments or a placebo, added to rehabilitation, in between the second day and the seventh day after surgery. Swelling was measured by blinded evaluators before surgery and at second day, seventh day, and 3 months using bioimpedance spectroscopy and volume measurement. Secondary outcomes were active and passive range of motion, pain, knee function, and gait parameters. At seventh day and 3 months, no outcome was significantly different between groups, except for the knee passive flexion contracture at 3 months, which was lower and less frequent in the MLD group (-2.6°; 95% confidence interval, -5.0° to -0.21°; P=.04; absolute risk reduction, 26.6%; 95% confidence interval, 0.9%-52.3%; number needed to treat, 4). The mean pain level decreased between 5.8 and 8.2mm on the visual analog scale immediately after MLD, which was significant after 4 of 5 MLD treatments. MLD treatments applied immediately after TKA surgery did not reduce swelling. It reduced pain immediately after the treatment. Further studies should investigate whether the positive effect of MLD on knee extension is replicable. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Insights Into Layering in the Cratonic Lithosphere Beneath Western Australia

NASA Astrophysics Data System (ADS)

Sun, Weijia; Fu, Li-Yun; Saygin, Erdinc; Zhao, Liang

2018-02-01

The characteristics of internal lithospheric discontinuities carry crucial information regarding the origin and evolution of the lithosphere. However, the formation and mechanisms of the midlithosphere discontinuity (MLD) are still enigmatic and controversial. We investigate the midlithospheric discontinuities beneath the Archean Western Australian Craton, which represents one of the oldest continents on the globe, using a novel receiver-based reflectivity approach combined with other geophysical information comprising tomographic P and S wave velocity, radial anisotropy, electrical resistivity, and heat flow data. The MLD is rather shallow with a depth of 68-82 km. Multiple prominent discontinuities are observed in the lithospheric mantle using constructed high-frequency (0.5-4 Hz) P wave reflectivities. These multiple discontinuities coincide well with the broad-scale reduction of relative P and SV wave velocities at the top of the graded transition zone from the lithosphere to the asthenosphere. Strong radial anisotropy in the upper lithosphere mantle tends to be weak across the MLD, which might reflect quasi-laminar lithospheric heterogeneity behavior with a horizontal correlation length that is greater than its vertical correlation length. Broad-scale electrical resistivity variations show little coherence with the MLD. Given these various geophysical observations, the upper lithosphere exhibits rigid and elastic properties above the MLD, while the lower lithosphere tends to be ductile and rheological or viscous. A model comprising quasi-laminar lithospheric heterogeneity could effectively represent the MLD characteristics beneath the Archean continent.

Organic and inorganic–organic thin film structures by molecular layer deposition: A review

PubMed Central

Sundberg, Pia

2014-01-01

Summary The possibility to deposit purely organic and hybrid inorganic–organic materials in a way parallel to the state-of-the-art gas-phase deposition method of inorganic thin films, i.e., atomic layer deposition (ALD), is currently experiencing a strongly growing interest. Like ALD in case of the inorganics, the emerging molecular layer deposition (MLD) technique for organic constituents can be employed to fabricate high-quality thin films and coatings with thickness and composition control on the molecular scale, even on complex three-dimensional structures. Moreover, by combining the two techniques, ALD and MLD, fundamentally new types of inorganic–organic hybrid materials can be produced. In this review article, we first describe the basic concepts regarding the MLD and ALD/MLD processes, followed by a comprehensive review of the various precursors and precursor pairs so far employed in these processes. Finally, we discuss the first proof-of-concept experiments in which the newly developed MLD and ALD/MLD processes are exploited to fabricate novel multilayer and nanostructure architectures by combining different inorganic, organic and hybrid material layers into on-demand designed mixtures, superlattices and nanolaminates, and employing new innovative nanotemplates or post-deposition treatments to, e.g., selectively decompose parts of the structure. Such layer-engineered and/or nanostructured hybrid materials with exciting combinations of functional properties hold great promise for high-end technological applications. PMID:25161845

The results of skin prick testing in patients with allergic rhinitis: a comparison between a multiple lancet device and a single lancet.

PubMed

Ateş, Aşkin; Kinikli, Gülay; Turgay, Murat; Aydoğan, Nergis; Duman, Murat

2004-01-01

Skin prick testing (SPT) is widely used in the assessment of allergic disorders. Different SPT techniques are widely used. The aim of this study was to compare the response to SPT using a multiple lancet device (MLD) with the results of a single lancet (SL). Fifty patients with allergic rhinitis were included in this study. Initially, SPT was performed by a SL technique. After one week SPT was repeated using the MLD on all patients. The patients were tested with a panel containing 19 specific allergens including grass pollen, tree pollen, house dust mites, weed pollen allergen extracts, histamine and a negative control. The skin responses were recorded after 15 minutes for each device by measuring the diameter of the wheal and the erythema. The skin wheal responses for grass pollen, tree pollen, weed pollen and house dust mite allergen extracts obtained using the SL were generally significantly larger than those using the MLD. The comparison between the MLD and the SL methods revealed that SPT was positive with SL and negative with MLD in 176 tests (15.3%), and on the contrary SPT was positive with MLD and negative with SL in only 13 tests (1%). In conclusion, we claim that SPT using SL shows a higher degree of sensitivity and reproducibility.

Calculation of Cumulative Distributions and Detection Probabilities in Communications and Optics.

DTIC Science & Technology

1984-10-01

the CMLD . As an example of a particular result, Figure 8.1 shows the additional SNR required (often called the CFAR loss) for the MLD, CMLD , and OSD in...the background noise level is known. Notice that although the CFAR loss increases with INR for the MLD, the CMLD and OSD have a bounded loss as the INR...Radar Detectors (J. A. Ritcey) Mean-level detectors (MLD) are commonly used in radar to maintain a constant -*! false-alarm rate ( CFAR ) when the

Manual lymph drainage efficiently reduces postoperative facial swelling and discomfort after removal of impacted third molars.

PubMed

Szolnoky, G; Szendi-Horváth, K; Seres, L; Boda, K; Kemény, L

2007-09-01

The removal of wisdom teeth is often associated with severe postoperative edema and pain, and operation on the third molar can cause local inflammation that impairs lymph transport. The objective of the study was to assess the efficacy of manual lymph drainage (MLD) in reducing swelling following bilateral wisdom tooth removal. Ten consecutive patients with bilateral impacted wisdom teeth that required surgical removal were enrolled in the study. Each patient was postoperatively treated with MLD (after Vodder's method) on one side of the neck region with the untreated contralateral side as a control. Swelling was evaluated using a tape-measure placed in contact with the skin. The six landmarks of measurement included tragus-lip junction, tragus-pogonion, mandibular angle-external corner of eye, mandibular angle-ala nasi, mandibular angle-lip junction, and mandibular angle-median point of chin. Subjective assessment of MLD was conducted with self-evaluation using a visual analogue bar scale (VAS, range 0-100 mm). Of the 6 linear measurements, 4 lines (2, 4, 5, 6) showed a significant reduction of swelling on the side of MLD compared to the untreated side. Mean score of VAS of pretreatment condition was 35.5 +/- 20.60 mm that decreased to 22 +/- 19.32 mm measured after MLD (p=0.0295). This initial study demonstrates that MLD may promote an improvement of lymph circulation and work in an adjunctive role for reduction of postoperative swelling and pain following removal of impacted third molars.

Properties of blocking and non-blocking monoclonal antibodies specific for human macrophage galactose-type C-type lectin (MGL/ClecSF10A/CD301).

PubMed

Sano, Yoshihiko; Usami, Katsuaki; Izawa, Ryota; Denda-Nagai, Kaori; Higashi, Nobuaki; Kimura, Toshifumi; Suzuki, Noriko; Irimura, Tatsuro

2007-01-01

Monoclonal antibodies (mAbs) specific for the human macrophage galactose-type calcium-type lectin (MGL) were established. The recombinant extracellular domain of MGL was used to immunize a mouse, and 10 hybridoma clones were obtained. Binding of recombinant MGL to asialo-bovine submaxillary mucin was shown to be blocked by mAbs MLD-1, 4 and 6. Immunoprecipitation of MGL from lysates of COS-1 cells transfected with MGL cDNA (form 6A) was achieved with mAbs MLD-1, 4, 7, 8 and 16. Chimeric recombinant proteins between human MGL and mouse MGL1 were used to determine the location of the epitopes for these mAbs. mAbs MLD-8, 13, 15 and 16 interacted with the amino terminal side of the conserved WVDGTD sequence immediately upstream of QPD, whereas mAbs MLD-7, 12 and 17 interacted with the other side. mAbs MLD-1, 4, and 6 apparently required both sides of this boundary. mAbs MLD-15 and 16 were shown to recognize the protein products of alternatively spliced mRNA 6A/8A and 6C/8A, having deletions at the boundary of exons 7 and 8, in addition to full length and other spliced forms of MGL (6A, 6B and 6C), whereas the other mAbs bound only full length and forms 6A, 6B and 6C.

Seasonal Variation of Submesoscale Flow Features in a Mesoscale Eddy-dominant Region in the East Sea

NASA Astrophysics Data System (ADS)

Chang, Yeon S.; Choi, Byoung-Ju; Park, Young-Gyu

2018-03-01

Seasonal changes in the distribution of submesoscale (SM) flow features were examined using a fine-resolution numerical simulation. The SM flows are expected to be strong where mesoscale (MS) eddies actively develop and also when the mixed layer depth (MLD) is deep due to enhanced baroclinic instability. In the East Sea (ES), MS eddies more actively develop in summer while the MLD is deeper in winter, which provided the motivation to conduct this study to test the effects of MLD and MS eddies on the SM activity in this region. Finite-scale Liapunov exponents and the vertical velocity components were employed to analyze the SM activities. It was found that the SM intensity was marked by seasonality: it is stronger in winter when the mixed layer is deep but weaker in summer - despite the greater eddy kinetic energy. This is because in summer the mixed layer is so thin that there is not enough available potential energy. When the SM activity was quantified based on parameterization, (MLD × density gradient), it was determined that the seasonal variation of MLD plays a more important role than the lateral density gradient variation on SM flow motion in the ES.

Induction of ebolavirus cross-species immunity using retrovirus-like particles bearing the Ebola virus glycoprotein lacking the mucin-like domain

PubMed Central

2012-01-01

Background The genus Ebolavirus includes five distinct viruses. Four of these viruses cause hemorrhagic fever in humans. Currently there are no licensed vaccines for any of them; however, several vaccines are under development. Ebola virus envelope glycoprotein (GP1,2) is highly immunogenic, but antibodies frequently arise against its least conserved mucin-like domain (MLD). We hypothesized that immunization with MLD-deleted GP1,2 (GPΔMLD) would induce cross-species immunity by making more conserved regions accessible to the immune system. Methods To test this hypothesis, mice were immunized with retrovirus-like particles (retroVLPs) bearing Ebola virus GPΔMLD, DNA plasmids (plasmo-retroVLP) that can produce such retroVLPs in vivo, or plasmo-retroVLP followed by retroVLPs. Results Cross-species neutralizing antibody and GP1,2-specific cellular immune responses were successfully induced. Conclusion Our findings suggest that GPΔMLD presented through retroVLPs may provide a strategy for development of a vaccine against multiple ebolaviruses. Similar vaccination strategies may be adopted for other viruses whose envelope proteins contain highly variable regions that may mask more conserved domains from the immune system. PMID:22273269

Induction of ebolavirus cross-species immunity using retrovirus-like particles bearing the Ebola virus glycoprotein lacking the mucin-like domain.

PubMed

Ou, Wu; Delisle, Josie; Jacques, Jerome; Shih, Joanna; Price, Graeme; Kuhn, Jens H; Wang, Vivian; Verthelyi, Daniela; Kaplan, Gerardo; Wilson, Carolyn A

2012-01-25

The genus Ebolavirus includes five distinct viruses. Four of these viruses cause hemorrhagic fever in humans. Currently there are no licensed vaccines for any of them; however, several vaccines are under development. Ebola virus envelope glycoprotein (GP1,2) is highly immunogenic, but antibodies frequently arise against its least conserved mucin-like domain (MLD). We hypothesized that immunization with MLD-deleted GP1,2 (GPΔMLD) would induce cross-species immunity by making more conserved regions accessible to the immune system. To test this hypothesis, mice were immunized with retrovirus-like particles (retroVLPs) bearing Ebola virus GPΔMLD, DNA plasmids (plasmo-retroVLP) that can produce such retroVLPs in vivo, or plasmo-retroVLP followed by retroVLPs. Cross-species neutralizing antibody and GP1,2-specific cellular immune responses were successfully induced. Our findings suggest that GPΔMLD presented through retroVLPs may provide a strategy for development of a vaccine against multiple ebolaviruses. Similar vaccination strategies may be adopted for other viruses whose envelope proteins contain highly variable regions that may mask more conserved domains from the immune system.

Deciphering the Temporal and Spatial Complexity in Submarine Canyons in Antarctica: the Role of Mixed Layer Depth in Regulating Primary Production

NASA Astrophysics Data System (ADS)

Carvalho, F.; Kohut, J. T.; Schofield, O.; Oliver, M. J.; Gorbunov, M. Y.

2016-02-01

There is a high spatial and temporal variability in the biophysical processes regulating primary productivity in submarine canyons in the West Antarctic Peninsula (WAP). WAP canyon heads are considered biological "hotspots" by providing predictable food resource and driving penguin foraging locations. Because the physiology and composition of the phytoplankton blooms and the physical mechanisms driving them aren't well understood, we aim to characterize the dynamics of the spring phytoplankton bloom at the head of a canyon in the WAP. A 6-year record of Slocum glider deployments is analyzed, corresponding to over 16,000 water column profiles. The mixed layer depth (MLD), determined by the maximum of the buoyancy frequency criteria, was found to be the MLD definition with the highest ecological relevance. The same holds true for other regions in Antarctica such as the Ross and Amundsen Seas. A FIRe sensor on a glider was used to evaluate physiological responses of phytoplankton to canyon dynamics using fluorescence kinetics. Initial results show a spatial influence, with increased photosynthetic efficiencies found at the canyon head. The strongest signal was the seasonal cycle. The shoaling of the MLD in early January results in increased chlorophyll a concentrations and as MLD deepens in mid season due to wind forcing, phytoplankton concentrations decrease, likely due to decreased light availability. A consistent secondary peak in chlorophyll matches a shoaling in MLD later in the growth season. A steady warming and increase in salinity of the MLD is seen throughout the season. Spatial differences were recorded at the head of the canyon and result from the local circulation. Shallower MLD found on the northern region are consistent with a fresher surface ocean (coastal influence) and increased chlorophyll concentrations. The southern region is thought to be more oceanic influenced as intrusions of warm deep water (mUCDW) to the upper water column were recorded regularly there.

GLUT2 in pancreatic islets: crucial target molecule in diabetes induced with multiple low doses of streptozotocin in mice.

PubMed

Wang, Z; Gleichmann, H

1998-01-01

In mice, diabetes can be induced by multiple low doses of streptozotocin (MLD-STZ), i.e., 40 mg/kg body wt on each of 5 consecutive days. In this model, diabetes develops only when STZ induces both beta-cell toxicity and T-cell-dependent immune reactions. The target molecule(s) of MLD-STZ-induced beta-cell toxicity are not known, however. In this study, we report that GLUT2 is a target molecule for MLD-STZ toxicity. Ex vivo, a gradual decrement of both GLUT2 protein and mRNA expression was found in pancreatic islets isolated from MLD-STZ-treated C57BL/6 male mice, whereas mRNA expression of beta-actin, glucokinase, and proinsulin remained unaffected. Significant reduction of both GLUT2 protein and mRNA expression was first noted 1 day after the third STZ injection, clearly preceding the onset of hyperglycemia. The extent of reduction increased with the number of STZ injections administered and increased over time, after the last, i.e., fifth, STZ injection. The STZ-induced reduction of GLUT2 protein and mRNA was not due to an essential loss of beta-cells, because ex vivo, not only the total RNA yield and protein content in isolated islets, but also proinsulin mRNA expression, failed to differ significantly in the differently treated groups. Furthermore, islets isolated from MLD-STZ-treated donors responded to the nonglucose secretagogue arginine in a pattern similar to that of solvent-treated donors. Interestingly, the MLD-STZ-induced reduction of both GLUT2 protein and mRNA was prevented by preinjecting mice with 5-thio-D-glucose before each STZ injection. Apparently, GLUT2 is a crucial target molecule of MLD-STZ toxicity, and this toxicity seems to precede the immune reactions against beta-cells.

Continuous quantitative measurement of the proximal airway dimensions and lung density on four-dimensional dynamic-ventilation CT in smokers

PubMed Central

Yamashiro, Tsuneo; Moriya, Hiroshi; Tsubakimoto, Maho; Matsuoka, Shin; Murayama, Sadayuki

2016-01-01

Purpose Four-dimensional dynamic-ventilation computed tomography (CT) imaging demonstrates continuous movement of the airways and lungs, which cannot be depicted with conventional CT. We aimed to investigate continuous changes in lung density and airway dimensions and to assess the correlation with spirometric values in smokers. Materials and methods This retrospective study was approved by the Institutional Review Board, and informed consent was waived. Twenty-one smokers including six patients with COPD underwent four-dimensional dynamic-ventilation CT during free breathing (160 mm in length). The mean lung density (MLD) of the scanned lung and luminal areas (Ai) of fixed points in the trachea and the right proximal bronchi (main bronchus, upper bronchus, bronchus intermedius, and lower bronchus) were continuously measured. Concordance between the time curve of the MLD and that of the airway Ai values was expressed by cross-correlation coefficients. The associations between these quantitative measurements and the forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) values were assessed by Spearman’s rank correlation analysis. Results On the time curve for the MLD, the Δ-MLD1.05 values between the peak inspiratory frame to the later third frame (1.05 seconds later) were strongly correlated with the FEV1/FVC (ρ=0.76, P<0.0001). The cross-correlation coefficients between the airway Ai and MLD values were significantly correlated with the FEV1/FVC (ρ=−0.56 to −0.66, P<0.01), except for the right upper bronchus. This suggested that the synchrony between the airway and lung movement was lost in patients with severe airflow limitation. Conclusion Respiratory changes in the MLD and synchrony between the airway Ai and the MLD measured with dynamic-ventilation CT were correlated with patient’s spirometric values. PMID:27110108

Three subdivisions of the auditory midbrain in chicks (Gallus gallus) identified by their afferent and commissural projections

PubMed Central

Wang, Yuan; Karten, Harvey J.

2010-01-01

The auditory midbrain is a site of convergence of multiple auditory channels from the brainstem. In birds, two separate ascending channels have been identified, through which time and intensity information is sent to nucleus mesencephalicus lateralis, pars dorsalis (MLd), the homologue of the central nucleus of mammalian inferior colliculus. Using in vivo anterograde and retrograde tracing techniques, the current study provides two lines of anatomical evidence supporting the presence of a third ascending channel to the chick MLd. First, three non-overlapping zones of MLd receive inputs from three distinct cell groups in the caudodorsal brainstem. The projections from nucleus angularis (NA) and nucleus laminaris (NL) are predominately contralateral and may correspond to the time and intensity channels. A rostromedial portion of MLd receives bilateral projections mainly from the Regio Intermedius, an interposed region of cells lying at a caudal level between NL and NA, as well as scattered neurons embedded in 8th nerve tract, and probably a very ventral region of NA. Second, the bilateral zones of MLd on two sides of the brain are reciprocally connected and do not interact with other zones of MLd via commissural connections. In contrast, the NL-recipient zone projects contralaterally upon the NA-recipient zone. The structural separation of the third pathway from the NA and NL projections suggests a third information-processing channel, in parallel with the time and intensity channels. Neurons in the third channel appear to process very low frequency information including infrasound, probably utilizing different mechanisms than that underlying higher frequency processing. PMID:20148439

Use of nicotine patches in breast-feeding mothers: transfer of nicotine and cotinine into human milk.

PubMed

Ilett, Kenneth F; Hale, Thomas W; Page-Sharp, Madhu; Kristensen, Judith H; Kohan, Rolland; Hackett, L Peter

2003-12-01

Our objective was to assess the extent of exposure to nicotine and cotinine in breast-fed infants during maternal smoking and later during maternal use of the nicotine transdermal patch to achieve smoking cessation. Fifteen lactating women (mean age, 32 years; mean weight, 72 kg) who were smokers (mean of 17 cigarettes per day) participated in a trial of the nicotine patch to assist in smoking cessation. Serial milk samples were collected from the women over sequential 24-hour periods when they were smoking and when they were stabilized on the 21-mg/d, 14-mg/d, and 7-mg/d nicotine patches. Nicotine and cotinine in milk were quantified by HPLC, and infant dose was calculated. Plasma concentrations of nicotine in the breast-fed infants were assessed, and the infants were also clinically assessed. Nicotine and cotinine concentrations in milk were not significantly different between smoking (mean of 17 cigarettes per day) and the 21-mg/d patch, but concentrations were significantly lower (P <.05) when patients were using the 14-mg/d and 7-mg/d patches than when smoking. There was also a downward trend in absolute infant dose (nicotine equivalents) from smoking or the 21-mg patch through to the 14-mg and 7-mg patches (P <.05 at both 14-mg and 7-mg doses, compared with smoking). Milk intake (shown as median and 25th to 75th percentile) by the breast-fed infants was similar while their mothers were smoking (585 mL/d [507-755 mL/d]) and subsequently when their mothers were using the 21-mg (717 mL/d [504-776 mL/d]), 14-mg (731 mL/d [535-864 mL/d]), and 7-mg (619 mL/d [520-706 mL/d]) patches (chi(2) = 3.19, P =.364). We conclude that the absolute infant dose of nicotine and its metabolite cotinine decreases by about 70% from when subjects were smoking or using the 21-mg patch to when they were using the 7-mg patch. In addition, use of the nicotine patch had no significant influence on the milk intake by the breast-fed infant. Undertaking maternal smoking cessation with the nicotine patch is, therefore, a safer option than continued smoking.

WE-AB-207B-12: Prospective Study of the Relationship Between Dose-Volume Clinical Toxicity and Patient Reported Outcomes in Lung Cancer Patients Treated with SBRT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mayyas, E; Vance, S; Brown, S

Purpose: To determine in a prospective study, the correlation between radiation dose/volume, clinical toxicities and patient-reported, quality of life (QOL) resulting from lung SBRT. Methods: For 106 non-small cell lung cancer (NSCLC) patients receiving SBRT (12 Gy × 4), symptoms including cough, dyspnea, fatigue and pneumonitis were measured at baseline (before treatment), after treatment and 3, 6, and 12 months post-treatment. Toxicity was graded from zero to five. Dosimetric parameters such as the MLD, D10%, D20%, and lung subvolumes (V10 and V20) were obtained from the treatment plan. Dosimetric parameters and number of patients demonstrating toxicity ≥ grade 2 weremore » tabulated. Linear regression analysis was used to calculate correlations between MLD and D10, D20, V10 and V20. Results: The percentages of patients with > grade 2 pneumonitis, fatigue, cough, and dyspnea over 3 to 12 months increased from 0.0% to 3.5%, 3.2% to 10.5%, 4.3% to 8.3%, and 10.8% to 18.8%, respectively. Computed dose indices D10%, D20% were 7.9±4.8 Gy and 3.0±2.3 Gy, respectively. MLD ranged from 0.34 Gy up to 9.9 Gy with overall average 3.0±1.7 Gy. The averages of the subvolumes V10 and V20 were respectively 8.9±5.3% and 3.0±2.4%. The linear regression analysis showed that V10 and D10 demonstrated the strongest correlation to MLD; R2= 0.92 and 0.87, respectively. V20, and D20 were also strongly correlated with MLD; R2 = 0.81 and 0.84 respectively. A correlation was also found to exist between MLD > 2 Gy and ≥ grade 2 cough and dyspnea. Subvolume values for 2Gy MLD were 5.3% for V10 and 2% for V20. Conclusion: Dosimetric indices: MLD ≥ 2Gy, D10 ≥ 5Gy and V10 ≥ 5% of the total lung volume were predictive of > grade 2 cough and dyspnea QOL data. The QOL results are a novel component of this work. acknowledgement of the Varian grant support.« less

The warmer the ocean surface, the shallower the mixed layer. How much of this is true?

PubMed Central

González‐Pola, C.; Fernández‐Diaz, J.

2017-01-01

Abstract Ocean surface warming is commonly associated with a more stratified, less productive, and less oxygenated ocean. Such an assertion is mainly based on consistent projections of increased near‐surface stratification and shallower mixed layers under global warming scenarios. However, while the observed sea surface temperature (SST) is rising at midlatitudes, the concurrent ocean record shows that stratification is not unequivocally increasing nor is MLD shoaling. We find that while SST increases at three study areas at midlatitudes, stratification both increases and decreases, and MLD deepens with enhanced deepening of winter MLDs at rates over 10 m  decade−1. These results rely on the estimation of several MLD and stratification indexes of different complexity on hydrographic profiles from long‐term hydrographic time‐series, ocean reanalysis, and Argo floats. Combining this information with estimated MLDs from buoyancy fluxes and the enhanced deepening/attenuation of the winter MLD trends due to changes in the Ekman pumping, MLD variability involves a subtle interplay between circulation and atmospheric forcing at midlatitudes. Besides, it is highlighted that the density difference between the surface and 200 m, the most widely used stratification index, should not be expected to reliably inform about changes in the vertical extent of mixing. PMID:29201584

Visible region MCD and MLD spectra of nitrosylferrohemoglobin and oxyhemoglobin.

PubMed

Pearce, Linda L; Bominaar, Emile L; Peterson, Jim

2002-09-20

Magnetic circular dichroism (MCD) and magnetic linear dichroism (MLD) spectroscopies at various applied magnetic fields (0-6T) and temperatures (2.0-31K) have been used to investigate the electronic properties of the visible (Q(0-0), or alpha band) region of oxy- and nitrosylferrohemoglobin (HbNO). OxyHb, a d(6) (S=0) diamagnet, exhibits the expected pseudo-first derivative MCD and pseudo-second derivative MLD temperature-independent features centered at 574nm. HbNO, a d(7) (S=1/2) paramagnet, also exhibits a temperature-independent pseudo-first derivative MCD spectrum, but centered at 571nm. So far as we are aware, this behavior is unprecedented in the MCD spectra of paramagetic iron-porphyrins, which are expected to be dominated by temperature-dependent C(0) terms. The HbNO MCD spectrum does, however, demonstrate limited field-dependent saturation magnetization behavior and the MLD spectrum is currently below the detection limit. In addition, an MCD signal from reoxygenated venous blood is reported and compared with MCD signals from oxy- and HbNO derivatives. Finally, a combination of MCD and MLD spectroscopies has been used to estimate the orbital angular momentum (M(L)) value of the alpha band excited state of oxyHb as 4.2 (+/-0.7).

Molecular layer deposition of APTES on silicon nanowire biosensors: Surface characterization, stability and pH response

NASA Astrophysics Data System (ADS)

Liang, Yuchen; Huang, Jie; Zang, Pengyuan; Kim, Jiyoung; Hu, Walter

2014-12-01

We report the use of molecular layer deposition (MLD) for depositing 3-aminopropyltriethoxysilane (APTES) on a silicon dioxide surface. The APTES monolayer was characterized using spectroscopic ellipsometry, contact angle goniometry, and atomic force microscopy. Effects of reaction time of repeating pulses and simultaneous feeding of water vapor with APTES were tested. The results indicate that the synergistic effects of water vapor and reaction time are significant for the formation of a stable monolayer. Additionally, increasing the number of repeating pulses improved the APTES surface coverage but led to saturation after 10 pulses. In comparing MLD with solution-phase deposition, the APTES surface coverage and the surface quality were nearly equivalent. The hydrolytic stability of the resulting films was also studied. The results confirmed that the hydrolysis process was necessary for MLD to obtain stable surface chemistry. Furthermore, we compared the pH sensing results of Si nanowire field effect transistors (Si NWFETs) modified by both the MLD and solution methods. The highly repeatable pH sensing results reflected the stability of APTES monolayers. The results also showed an improved pH response of the sensor prepared by MLD compared to the one prepared by the solution treatment, which indicated higher surface coverage of APTES.

The role of off-frequency masking in binaural hearing

PubMed Central

Buss, Emily; Hall, Joseph W.

2010-01-01

The present studies examined the binaural masking level difference (MLD) for off-frequency masking. It has been shown previously that the MLD decreases steeply with increasing spectral separation between a pure tone signal and a 10-Hz wide band of masking noise. Data collected here show that this reduction in the off-frequency MLD as a function of signal∕masker separation is comparable at 250 and 2500 Hz, indicating that neither interaural phase cues nor frequency resolution are critical to this finding. The MLD decreases more gradually with spectral separation when the masker is a 250-Hz-wide band of noise, a result that implicates the rate of inherent amplitude modulation of the masker. Thresholds were also measured for a brief signal presented coincident with a local masker modulation minimum or maximum. Sensitivity was better in the minima for all NoSπ and off-frequency NoSo conditions, with little or no effect of signal position for on-frequency NoSo conditions. Taken together, the present results indicate that the steep reduction in the off-frequency MLD for a narrowband noise masker is due at least in part to envelope cues in the NoSo conditions. There was no evidence of a reduction in binaural cue quality for off-frequency masking. PMID:20550265

The warmer the ocean surface, the shallower the mixed layer. How much of this is true?

PubMed

Somavilla, R; González-Pola, C; Fernández-Diaz, J

2017-09-01

Ocean surface warming is commonly associated with a more stratified, less productive, and less oxygenated ocean. Such an assertion is mainly based on consistent projections of increased near-surface stratification and shallower mixed layers under global warming scenarios. However, while the observed sea surface temperature (SST) is rising at midlatitudes, the concurrent ocean record shows that stratification is not unequivocally increasing nor is MLD shoaling. We find that while SST increases at three study areas at midlatitudes, stratification both increases and decreases, and MLD deepens with enhanced deepening of winter MLDs at rates over 10 m  decade-1. These results rely on the estimation of several MLD and stratification indexes of different complexity on hydrographic profiles from long-term hydrographic time-series, ocean reanalysis, and Argo floats. Combining this information with estimated MLDs from buoyancy fluxes and the enhanced deepening/attenuation of the winter MLD trends due to changes in the Ekman pumping, MLD variability involves a subtle interplay between circulation and atmospheric forcing at midlatitudes. Besides, it is highlighted that the density difference between the surface and 200 m, the most widely used stratification index, should not be expected to reliably inform about changes in the vertical extent of mixing.

ACTN3 R577X genotype and performance of elite middle-long distance swimmers in China

PubMed Central

Li, YC; Wang, LQ; Yi, LY; Liu, JH; Lu, YF; Wang, M

2016-01-01

The ACTN3 gene is one of the genes that have a potential influence on physical performance. Studies have shown that the 577R genotype of ACTN3 is more prevalent in sprint athletes, while the 577X genotype is more prevalent in endurance athletes. In swimming, both power and endurance related phenotypes are equally needed for swimmers to excel at the elite level. Therefore, the ACTN3 R577X polymorphism may become a genetic marker for swimmers. The study aimed to examine the association of the ACTN3 R577X genotype with the performance of elite middle-long distance (MLD) swimmers. The distributions of the ACTN3 R577X (rs1815739) genotype and allele were examined in a general population (206) and a group of elite MLD swimmers (160) in China by using PCR-RFLP and TOF. Compared with the general population, the elite MLD swimmers, especially the females, had a higher frequency of the RR genotype. The swimmers had a higher frequency of the R allele than the general population. However, the difference was not statistically significant. After being stratified by performance, the difference of the R allele frequency between the international master athletes and the general population was statistically significant. The elite MLD swimmers had a higher frequency of the RR genotype than the RX+XX genotype compared with the general population. The ACTN3 R577X polymorphism was associated with the performance of elite MLD swimmers in China. The SNP R577X could be used as a biomarker for selecting elite MLD swimmers in China. PMID:28416896

Apolipoprotein E genotype and LRP1 polymorphisms in patients with different clinical types of metachromatic leukodystrophy.

PubMed

Ługowska, Agnieszka; Musielak, Małgorzata; Jamroz, Ewa; Pyrkosz, Antoni; Kmieć, Tomasz; Tylki-Szymańska, Anna; Bednarska-Makaruk, Małgorzata

2013-09-10

Metachromatic leukodystrophy (MLD) is a severe, neurodegenerative, metabolic disease which is caused by deficient activity of arylsulfatase A (ARSA). Sulfatides and other substrates of ARSA are stored in central and peripheral nervous systems, and in some other organs. Accumulated sulfatides are especially toxic to oligodendrocytes and Schwann cells leading to progressive demyelination. The kind of apolipoprotein E (apoE) isoform is of essential significance for the modulation of sulfatide quantity in the brain as apoE4 contains more sulfatides than apoE3. Taking into consideration the fact that apoE4 leads to the loss of sulfatides in CSF of Alzheimer's disease patients, we examined if apoE isoforms display any impact on clinical outcome in patients with different forms of MLD in whom sulfatides accumulate. The significant association of age at the onset of MLD symptoms with APOE ε2/ε3/ε4 and LRP1 c.766C>T polymorphisms was shown in multivariate stepwise regression analysis, in which other factors known to affect age at onset of the disease, i.e. clinical type of MLD, family connection of the patient and sex were also analyzed. As expected, the clinical type of MLD explained about 80% of the variance of the dependent variable. The impact of both polymorphisms on age of onset of the disease was considerably lower: 2.0% in the case of APOE polymorphism and 1.0% in the case of LRP1 polymorphism. Thus, the clinical outcome in MLD patients is related principally to the genotype of the ARSA gene, while the polymorphisms in the APOE and LRP1 genes are only slightly modifying factors. Copyright © 2013 Elsevier B.V. All rights reserved.

Gallbladder and the risk of polyps and carcinoma in metachromatic leukodystrophy.

PubMed

van Rappard, Diane F; Bugiani, Marianna; Boelens, Jaap J; van der Steeg, Alida F W; Daams, Freek; de Meij, Tim G J; van Doorn, Martine M A C; van Hasselt, Peter M; Gouma, Dirk J; Verbeke, Jonathan I M L; Hollak, Carla E M; van Hecke, Wim; Salomons, Gajja S; van der Knaap, Marjo S; Wolf, Nicole I

2016-07-05

To assess frequency of gallbladder polyposis and carcinoma in metachromatic leukodystrophy (MLD). We evaluated 34 patients with MLD (average age 16.7 years, age range 2-39 years) screened for gallbladder abnormalities by ultrasound. In the case of cholecystectomy, findings at pathology were reviewed. Only 8 of 34 patients (23%) had a normal gallbladder at ultrasound. Gallbladder polyps were visible in 8 patients (23%). Cholecystectomy was performed in 11 patients (32%). In these, pathology revealed various abnormalities, including hyperplastic polyps, intestinal metaplasia, prominent Rokitansky-Aschoff sinuses, and sulfatide storage. Our results demonstrate that gallbladder involvement is the rule rather than the exception in MLD. The high prevalence of hyperplastic polyps, a known precancerous condition, and one death from gallbladder carcinoma at a young age suggest that MLD predisposes to neoplastic gallbladder abnormalities. As novel therapies for this patient group are emerging leading to increased life expectancy, we recommend screening for gallbladder abnormalities by ultrasound in order to prevent early death. © 2016 American Academy of Neurology.

Medical and Transmission Vector Vocabulary Alignment with Schema.org

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, William P.; Chappell, Alan R.; Corley, Courtney D.

Available biomedical ontologies and knowledge bases currently lack formal and standards-based interconnections between disease, disease vector, and drug treatment vocabularies. The PNNL Medical Linked Dataset (PNNL-MLD) addresses this gap. This paper describes the PNNL-MLD, which provides a unified vocabulary and dataset of drug, disease, side effect, and vector transmission background information. Currently, the PNNL-MLD combines and curates data from the following research projects: DrugBank, DailyMed, Diseasome, DisGeNet, Wikipedia Infobox, Sider, and PharmGKB. The main outcomes of this effort are a dataset aligned to Schema.org, including a parsing framework, and extensible hooks ready for integration with selected medical ontologies. The PNNL-MLDmore » enables researchers more quickly and easily to query distinct datasets. Future extensions to the PNNL-MLD will include Traditional Chinese Medicine, broader interlinks across genetic structures, a larger thesaurus of synonyms and hypernyms, explicit coding of diseases and drugs across research systems, and incorporating vector-borne transmission vocabularies.« less

The Effect of Otitis Media with Effusion on the Masking-Level Difference and the Auditory Brainstem Response.

ERIC Educational Resources Information Center

Hall, Joseph W.; Grose, John H.

1993-01-01

This study of 14 children (ages 5-9) with a history of otitis media with effusion found that subjects had significantly reduced masking-level differences (MLD) compared to controls. Results suggest that the reduction in MLD may be related to abnormal brainstem processing. (Author/JDD)

Gene Therapy for Metachromatic Leukodystrophy

PubMed Central

Rosenberg, Jonathan B.; Kaminsky, Stephen M.; Aubourg, Patrick; Crystal, Ronald G.; Sondhi, Dolan

2016-01-01

Summary Leukodystrophies are rare white matter genetic disorders of the central nervous system (CNS) with progressive neurologic deterioration. One approach to the treatment of leukodystrophies is by gene therapy. Using metachromatic leukodystrophy (MLD), a leukodystrophy resulting from deficiency of a lysosomal catabolic enzyme arylsulfatase A (ARSA) as the example, this review is focused on the current status of preclinical and clinical development of gene therapy as a viable treatment option for leukodystrophies. In MLD, mutations in the ARSA gene result in excess buildup of sulfatides, which triggers apoptosis of glia and neurons. The disease is characterized by severe cerebral demyelination and atrophy, with progressive loss of oligodendrocytes, neurons and Schwann cells. The optimal therapy for MLD would provide persistent and high level expression of ARSA in the CNS. Gene therapy using adeno-associated virus (AAV) is an ideal choice for clinical development as it provides the best balance of potential for efficacy with a reduced safety risk profile. In this review, we have summarized preclinical data that support the use of a gene therapy with the AAVrh.10 serotype for clinical development as a treatment for MLD. PMID:27638601

Intercomparison and validation of the mixed layer depth fields of global ocean syntheses

NASA Astrophysics Data System (ADS)

Toyoda, Takahiro; Fujii, Yosuke; Kuragano, Tsurane; Kamachi, Masafumi; Ishikawa, Yoichi; Masuda, Shuhei; Sato, Kanako; Awaji, Toshiyuki; Hernandez, Fabrice; Ferry, Nicolas; Guinehut, Stéphanie; Martin, Matthew J.; Peterson, K. Andrew; Good, Simon A.; Valdivieso, Maria; Haines, Keith; Storto, Andrea; Masina, Simona; Köhl, Armin; Zuo, Hao; Balmaseda, Magdalena; Yin, Yonghong; Shi, Li; Alves, Oscar; Smith, Gregory; Chang, You-Soon; Vernieres, Guillaume; Wang, Xiaochun; Forget, Gael; Heimbach, Patrick; Wang, Ou; Fukumori, Ichiro; Lee, Tong

2017-08-01

Intercomparison and evaluation of the global ocean surface mixed layer depth (MLD) fields estimated from a suite of major ocean syntheses are conducted. Compared with the reference MLDs calculated from individual profiles, MLDs calculated from monthly mean and gridded profiles show negative biases of 10-20 m in early spring related to the re-stratification process of relatively deep mixed layers. Vertical resolution of profiles also influences the MLD estimation. MLDs are underestimated by approximately 5-7 (14-16) m with the vertical resolution of 25 (50) m when the criterion of potential density exceeding the 10-m value by 0.03 kg m-3 is used for the MLD estimation. Using the larger criterion (0.125 kg m-3) generally reduces the underestimations. In addition, positive biases greater than 100 m are found in wintertime subpolar regions when MLD criteria based on temperature are used. Biases of the reanalyses are due to both model errors and errors related to differences between the assimilation methods. The result shows that these errors are partially cancelled out through the ensemble averaging. Moreover, the bias in the ensemble mean field of the reanalyses is smaller than in the observation-only analyses. This is largely attributed to comparably higher resolutions of the reanalyses. The robust reproduction of both the seasonal cycle and interannual variability by the ensemble mean of the reanalyses indicates a great potential of the ensemble mean MLD field for investigating and monitoring upper ocean processes.

Connections of the Auditory Brainstem in a Songbird, Taeniopygia guttata. III. Projections of the Superior Olive and Lateral Lemniscal Nuclei

PubMed Central

Wild, J. Martin; Krützfeldt, Nils O.E.; Kubke, M. Fabiana

2013-01-01

Sequential to companion articles that report the projections of the cochlear nucleus angularis (NA) and the third-order nucleus laminaris (NL) to the central nucleus of the inferior colliculus (MLd) and to the superior olive (OS) and lateral lemniscal nuclei (LLV, LLI, and LLD) (Krützfeldt et al., J Comp Neurol, this issue), we here describe the projections of the latter group of nuclei using standard tract-tracing methods. OS projects on LLV and both have further ascending projections on LLI, LLD, and MLd. LLV also provides auditory input to the song system, via nucleus uvaeformis, and to the thalamo-telencephalic auditory system, via nucleus ovoidalis (Ov), thus bypassing MLd. The two divisions of LLD (LLDa and LLDp) project across the midline via the commissure of Probst each to innervate the homologous contralateral nucleus and MLd. Both, particularly LLDp, also project on Ov. Injections in LLD and LLV resulted in anterograde labeling of caudal nucleus basorostralis (Bas) in the frontal telencephalon, but retrograde tracing so far suggests that only LLI is a real source of this projection (Wild and Farabaugh [1996] J Comp Neurol 365:306–328). OS and LLV also have descending projections on the ipsilateral NA, NM, and NL, and LLV also projects on OS. The ascending inputs to MLd and more rostral nuclei may contribute importantly to mechanisms of auditory pattern (song) recognition. Consistent with previous studies, some of the descending projections may be inhibitory. PMID:20394063

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Jingbo; Department of Radiation Oncology, Cancer Hospital, Chinese Academic Medical Sciences and Peking Union Medical College, Beijing; Cao, Jianzhong

Purpose: Poor pulmonary function (PF) is often considered a contraindication to definitive radiation therapy for lung cancer. This study investigated whether baseline PF was associated with radiation-induced lung toxicity (RILT) in patients with non-small cell lung cancer (NSCLC) receiving conformal radiation therapy (CRT). Methods and Materials: NSCLC patients treated with CRT and tested for PF at baseline were eligible. Baseline predicted values of forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC), and diffusion capacity of lung for carbon monoxide (DLCO) were analyzed. Additional factors included age, gender, smoking status, Karnofsky performance status, coexisting chronic obstructive pulmonary diseasemore » (COPD), tumor location, histology, concurrent chemotherapy, radiation dose, and mean lung dose (MLD) were evaluated for RILT. The primary endpoint was symptomatic RILT (SRILT), including grade ≥2 radiation pneumonitis and fibrosis. Results: There was a total of 260 patients, and SRILT occurred in 58 (22.3%) of them. Mean FEV1 values for SRILT and non-SRILT patients were 71.7% and 65.9% (P=.077). Under univariate analysis, risk of SRILT increased with MLD (P=.008), the absence of COPD (P=.047), and FEV1 (P=.077). Age (65 split) and MLD were significantly associated with SRILT in multivariate analysis. The addition of FEV1 and age with the MLD-based model slightly improved the predictability of SRILT (area under curve from 0.63-0.70, P=.088). Conclusions: Poor baseline PF does not increase the risk of SRILT, and combining FEV1, age, and MLD may improve the predictive ability.« less

Intravascular Ultrasound and Angiographic Predictors of In-Stent Restenosis of Chronic Total Occlusion Lesions.

PubMed

Kang, Jeehoon; Cho, Young-Seok; Kim, Seong-Wook; Park, Jin Joo; Yoon, Yeonyee E; Oh, Il-Young; Yoon, Chang-Hwan; Suh, Jung-Won; Youn, Tae-Jin; Chae, In-Ho; Choi, Dong-Ju

2015-01-01

Despite the benefits of successful percutaneous coronary interventions (PCIs) for chronic total occlusion (CTO) lesions, PCIs of CTO lesions still carry a high rate of adverse events, including in-stent restenosis (ISR). Because previous reports have not specifically investigated the intravascular ultrasound (IVUS) predictors of ISR in CTO lesions, we focused on these predictors. We included 126 patients who underwent successful PCIs, using drug-eluting stents, and post-PCI IVUS of CTO lesions. Patient and lesion characteristics were analyzed to elucidate the ISR predictors. In each lesion, an average of 1.7 ± 0.7 (mean length, 46.4 ± 20.3 mm) stents were used. At 9 months follow-up, 14 (11%) patients demonstrated ISR, and 8 (6.3%) underwent target lesion revascularization. Multivariate logistic regression analysis showed that the independent predictors of ISR were the post-PCI minimal luminal diameter (MLD) and the stent expansion ratio (SER; minimal stent cross-sectional area (CSA) over the nominal CSA of the implanted stent), measured using quantitative coronary angiography (QCA) and IVUS, respectively. A receiver operating characteristic analysis indicated that the best post-PCI MLD and SER cut-off values for predicting ISR were 2.4 mm (area under the curve [AUC], 0.762; 95% confidence interval (CI), 0.639-0.885) and 70% (AUC, 0.714; 95% CI, 0.577-0.852), respectively. Lesions with post-PCI MLD and SER values less than these threshold values were at a higher risk of ISR, with an odds ratio of 23.3 (95% CI, 2.74-198.08), compared with lesions having larger MLD and SER values. Thus, the potential predictors of ISR, after PCI of CTO lesions, are the post-PCI MLD and SER values. The ISR rate was highest in lesions with a post-PCI MLD ≤2.4 mm and an SER ≤70%.

Predicting pneumonitis risk: a dosimetric alternative to mean lung dose.

PubMed

Tucker, Susan L; Mohan, Radhe; Liengsawangwong, Raweewan; Martel, Mary K; Liao, Zhongxing

2013-02-01

To determine whether the association between mean lung dose (MLD) and risk of severe (grade ≥3) radiation pneumonitis (RP) depends on the dose distribution pattern to normal lung among patients receiving 3-dimensional conformal radiation therapy for non-small-cell lung cancer. Three cohorts treated with different beam arrangements were identified. One cohort (2-field boost [2FB]) received 2 parallel-opposed (anteroposterior-posteroanterior) fields per fraction initially, followed by a sequential boost delivered using 2 oblique beams. The other 2 cohorts received 3 or 4 straight fields (3FS and 4FS, respectively), ie, all fields were irradiated every day. The incidence of severe RP was plotted against MLD in each cohort, and data were analyzed using the Lyman-Kutcher-Burman (LKB) model. The incidence of grade ≥3 RP rose more steeply as a function of MLD in the 2FB cohort (N=120) than in the 4FS cohort (N=138), with an intermediate slope for the 3FS group (N=99). The estimated volume parameter from the LKB model was n=0.41 (95% confidence interval, 0.15-1.0) and led to a significant improvement in fit (P=.05) compared to a fit with volume parameter fixed at n=1 (the MLD model). Unlike the MLD model, the LKB model with n=0.41 provided a consistent description of the risk of severe RP in all three cohorts (2FB, 3FS, 4FS) simultaneously. When predicting risk of grade ≥3 RP, the mean lung dose does not adequately take into account the effects of high doses. Instead, the effective dose, computed from the LKB model using volume parameter n=0.41, may provide a better dosimetric parameter for predicting RP risk. If confirmed, these findings support the conclusion that for the same MLD, high doses to small lung volumes ("a lot to a little") are worse than low doses to large volumes ("a little to a lot"). Copyright © 2013 Elsevier Inc. All rights reserved.

Low-Temperature Molecular Layer Deposition Using Monofunctional Aromatic Precursors and Ozone-Based Ring-Opening Reactions.

PubMed

Svärd, Laura; Putkonen, Matti; Kenttä, Eija; Sajavaara, Timo; Krahl, Fabian; Karppinen, Maarit; Van de Kerckhove, Kevin; Detavernier, Christophe; Simell, Pekka

2017-09-26

Molecular layer deposition (MLD) is an increasingly used deposition technique for producing thin coatings consisting of purely organic or hybrid inorganic-organic materials. When organic materials are prepared, low deposition temperatures are often required to avoid decomposition, thus causing problems with low vapor pressure precursors. Monofunctional compounds have higher vapor pressures than traditional bi- or trifunctional MLD precursors, but do not offer the required functional groups for continuing the MLD growth in subsequent deposition cycles. In this study, we have used high vapor pressure monofunctional aromatic precursors in combination with ozone-triggered ring-opening reactions to achieve sustained sequential growth. MLD depositions were carried out by using three different aromatic precursors in an ABC sequence, namely with TMA + phenol + O 3 , TMA + 3-(trifluoromethyl)phenol + O 3 , and TMA + 2-fluoro-4-(trifluoromethyl)benzaldehyde + O 3 . Furthermore, the effect of hydrogen peroxide as a fourth step was evaluated for all studied processes resulting in a four-precursor ABCD sequence. According to the characterization results by ellipsometry, infrared spectroscopy, and X-ray reflectivity, self-limiting MLD processes could be obtained between 75 and 150 °C with each of the three aromatic precursors. In all cases, the GPC (growth per cycle) decreased with increasing temperature. In situ infrared spectroscopy indicated that ring-opening reactions occurred in each ABC sequence. Compositional analysis using time-of-flight elastic recoil detection indicated that fluorine could be incorporated into the film when 3-(trifluoromethyl)phenol and 2-fluoro-4-(trifluoromethyl)benzaldehyde were used as precursors.

Interannual and seasonal variability of winter-spring cohort of neon flying squid abundance in the Northwest Pacific Ocean during 1995-2011

NASA Astrophysics Data System (ADS)

Yu, Wei; Chen, Xinjun; Yi, Qian

2016-06-01

The neon flying squid, Ommastrephes bartramii, is a species of economically important cephalopod in the Northwest Pacific Ocean. Its short lifespan increases the susceptibility of the distribution and abundance to the direct impact of the environmental conditions. Based on the generalized linear model (GLM) and generalized additive model (GAM), the commercial fishery data from the Chinese squid-jigging fleets during 1995 to 2011 were used to examine the interannual and seasonal variability in the abundance of O. bartramii, and to evaluate the influences of variables on the abundance (catch per unit effort, CPUE). The results from GLM suggested that year, month, latitude, sea surface temperature (SST), mixed layer depth (MLD), and the interaction term ( SST×MLD) were significant factors. The optimal model based on GAM included all the six significant variables and could explain 42.43% of the variance in nominal CPUE. The importance of the six variables was ranked by decreasing magnitude: year, month, latitude, SST, MLD and SST×MLD. The squid was mainly distributed in the waters between 40°N and 44°N in the Northwest Pacific Ocean. The optimal ranges of SST and MLD were from 14 to 20°C and from 10 to 30 m, respectively. The squid abundance greatly fluctuated from 1995 to 2011. The CPUE was low during 1995-2002 and high during 2003-2008. Furthermore, the squid abundance was typically high in August. The interannual and seasonal variabilities in the squid abundance were associated with the variations of marine environmental conditions and the life history characteristics of squid.

SU-F-T-687: Comparison of SPECT/CT-Based Methodologies for Estimating Lung Dose from Y-90 Radioembolization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kost, S; Yu, N; Lin, S

2016-06-15

Purpose: To compare mean lung dose (MLD) estimates from 99mTc macroaggregated albumin (MAA) SPECT/CT using two published methodologies for patients treated with {sup 90}Y radioembolization for liver cancer. Methods: MLD was estimated retrospectively using two methodologies for 40 patients from SPECT/CT images of 99mTc-MAA administered prior to radioembolization. In these two methods, lung shunt fractions (LSFs) were calculated as the ratio of scanned lung activity to the activity in the entire scan volume or to the sum of activity in the lung and liver respectively. Misregistration of liver activity into the lungs during SPECT acquisition was overcome by excluding lungmore » counts within either 2 or 1.5 cm of the diaphragm apex respectively. Patient lung density was assumed to be 0.3 g/cm{sup 3} or derived from CT densitovolumetry respectively. Results from both approaches were compared to MLD determined by planar scintigraphy (PS). The effect of patient size on the difference between MLD from PS and SPECT/CT was also investigated. Results: Lung density from CT densitovolumetry is not different from the reference density (p = 0.68). The second method resulted in lung dose of an average 1.5 times larger lung dose compared to the first method; however the difference between the means of the two estimates was not significant (p = 0.07). Lung dose from both methods were statistically different from those estimated from 2D PS (p < 0.001). There was no correlation between patient size and the difference between MLD from PS and both SPECT/CT methods (r < 0.22, p > 0.17). Conclusion: There is no statistically significant difference between MLD estimated from the two techniques. Both methods are statistically different from conventional PS, with PS overestimating dose by a factor of three or larger. The difference between lung doses estimated from 2D planar or 3D SPECT/CT is not dependent on patient size.« less

Angiographic core laboratory reproducibility analyses: implications for planning clinical trials using coronary angiography and left ventriculography end-points.

PubMed

Steigen, Terje K; Claudio, Cheryl; Abbott, David; Schulzer, Michael; Burton, Jeff; Tymchak, Wayne; Buller, Christopher E; John Mancini, G B

2008-06-01

To assess reproducibility of core laboratory performance and impact on sample size calculations. Little information exists about overall reproducibility of core laboratories in contradistinction to performance of individual technicians. Also, qualitative parameters are being adjudicated increasingly as either primary or secondary end-points. The comparative impact of using diverse indexes on sample sizes has not been previously reported. We compared initial and repeat assessments of five quantitative parameters [e.g., minimum lumen diameter (MLD), ejection fraction (EF), etc.] and six qualitative parameters [e.g., TIMI myocardial perfusion grade (TMPG) or thrombus grade (TTG), etc.], as performed by differing technicians and separated by a year or more. Sample sizes were calculated from these results. TMPG and TTG were also adjudicated by a second core laboratory. MLD and EF were the most reproducible, yielding the smallest sample size calculations, whereas percent diameter stenosis and centerline wall motion require substantially larger trials. Of the qualitative parameters, all except TIMI flow grade gave reproducibility characteristics yielding sample sizes of many 100's of patients. Reproducibility of TMPG and TTG was only moderately good both within and between core laboratories, underscoring an intrinsic difficulty in assessing these. Core laboratories can be shown to provide reproducibility performance that is comparable to performance commonly ascribed to individual technicians. The differences in reproducibility yield huge differences in sample size when comparing quantitative and qualitative parameters. TMPG and TTG are intrinsically difficult to assess and conclusions based on these parameters should arise only from very large trials.

Comparison of four software packages for CT lung volumetry in healthy individuals.

PubMed

Nemec, Stefan F; Molinari, Francesco; Dufresne, Valerie; Gosset, Natacha; Silva, Mario; Bankier, Alexander A

2015-06-01

To compare CT lung volumetry (CTLV) measurements provided by different software packages, and to provide normative data for lung densitometric measurements in healthy individuals. This retrospective study included 51 chest CTs of 17 volunteers (eight men and nine women; mean age, 30 ± 6 years), who underwent spirometrically monitored CT at total lung capacity (TLC), functional residual capacity (FRC), and mean inspiratory capacity (MIC). Volumetric differences assessed by four commercial software packages were compared with analysis of variance (ANOVA) for repeated measurements and benchmarked against the threshold for acceptable variability between spirometric measurements. Mean lung density (MLD) and parenchymal heterogeneity (MLD-SD) were also compared with ANOVA. Volumetric differences ranged from 12 to 213 ml (0.20 % to 6.45 %). Although 16/18 comparisons (among four software packages at TLC, MIC, and FRC) were statistically significant (P < 0.001 to P = 0.004), only 3/18 comparisons, one at MIC and two at FRC, exceeded the spirometry variability threshold. MLD and MLD-SD significantly increased with decreasing volumes, and were significantly larger in lower compared to upper lobes (P < 0.001). Lung volumetric differences provided by different software packages are small. These differences should not be interpreted based on statistical significance alone, but together with absolute volumetric differences. • Volumetric differences, assessed by different CTLV software, are small but statistically significant. • Volumetric differences are smaller at TLC than at MIC and FRC. • Volumetric differences rarely exceed spirometric repeatability thresholds at MIC and FRC. • Differences between CTLV measurements should be interpreted based on comparison of absolute differences. • MLD increases with decreasing volumes, and is larger in lower compared to upper lobes.

Effects of lymphatic drainage and cryotherapy on indirect markers of muscle damage.

PubMed

Behringer, Michael; Jedlicka, Diana; Mester, Joachim

2018-06-01

Muscle enzymes are cleared from the extracellular space by the lymphatic system, while smaller proteins enter the bloodstream directly. We investigated if manual lymphatic drainage (MLD), local cryotherapy (CRY), and rest (RST) differently affect the time course of creatine kinase (CK, 84 kDa) and heart-type fatty acid binding protein (h-FABP, 15 kDa) in the blood. Randomized controlled trial. After 4x20 unilateral, eccentric accentuated knee extensions (with one-third of the maximal isometric force) 30 sports students randomly received either a 30 min MLD, CRY or they rested (RST) for the same amount of time. CK, h-FABP, neutrophil granulocytes, and the perceived muscle soreness were assessed before, immediately after, and 1 hour, 4 hours, and 24 hours after the exercise. All measures increased significantly (P<0.001) after the protocol indicating that muscle damage was induced. However, the responses did not differ between the treatments. Large and small damage markers were not affected differently by MLD, CRY, or RST, when applied for 30 min and no beneficial effects on inflammation or muscle soreness could be found for MLD and CRY when compared to RST. This information is particularly important for those sports physicians and conditioning specialists who use biochemical muscle damage markers to adjust the training load and volume of athletes.

Measurement of functional task difficulty during motor learning: What level of difficulty corresponds to the optimal challenge point?

PubMed

Akizuki, Kazunori; Ohashi, Yukari

2015-10-01

The relationship between task difficulty and learning benefit was examined, as was the measurability of task difficulty. Participants were required to learn a postural control task on an unstable surface at one of four different task difficulty levels. Results from the retention test showed an inverted-U relationship between task difficulty during acquisition and motor learning. The second-highest level of task difficulty was the most effective for motor learning, while learning was delayed at the most and least difficult levels. Additionally, the results indicate that salivary α-amylase and the performance dimension of the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) are useful indices of task difficulty. Our findings suggested that instructors may be able to adjust task difficulty based on salivary α-amylase and the performance dimension of the NASA-TLX to enhance learning. Copyright © 2015 Elsevier B.V. All rights reserved.

Evaluating the Sonic Layer Depth Relative to the Mixed Layer Depth

DTIC Science & Technology

2008-07-24

upper ocean to trap acoustic energy in a surface duct while MLD characterizes upper ocean mixing. The SLD is computed from temperature and salinity...and compared over the annual cycle. The SLD characterizes the potential of the upper ocean to trap acoustic energy in a surface duct while MLD...exists a tropical cyclone formation [e.g., Mao et al., 2000], to Minimum acoustic Cutoff Frequency (MCF) above which phytoplankton bloom critical depth

Diffusion and ADC-map images detect ongoing demyelination on subcortical white matter in an adult metachromatic leukodystrophy patient with autoimmune Hashimoto thyroiditis

PubMed Central

Miura, Akiko; Kumabe, Yuri; Kimura, En; Yamashita, Satoshi; Ueda, Akihiko; Hirano, Teruyuki; Uchino, Makoto

2010-01-01

Adult-onset metachromatic leukodystrophy (MLD) often shows schizophrenia- or encephalopathy-like symptoms at an early stage, such as behavioural abnormalities, cognitive impairment, mood disorders and hallucinations. The authors report the case of an adult woman with MLD who had been given antipsychotic medication for schizophrenia. In the differential diagnosis, screening of auto-antibodies was important for ruling out other encephalopathies as she had a euthyroid Hashimoto thyroiditis. Diagnosis was based the results of MRI, nerve conduction velocity, sensory evoked potential, motor evoked potential, lysosomal enzyme activity and gene analysis studies. Brain MRI showed diffuse demyelination spreading from the deep white matter to subcortical area as high signals at the edges of these lesions in diffusion and apparent diffusion coefficient-map images with the U-fibres conserved. The authors diagnosed adult-onset MLD coexisting with euthyroid autoimmune Hashimoto thyroiditis. PMID:22798296

Historic water-level changes and pumpage from the principal aquifers of the Memphis area, Tennessee: 1886-1975

USGS Publications Warehouse

Criner, James H.; Parks, William Scott

1976-01-01

Pumpage from the Fort Pillow Sand ("1,400-foot" sand) began in 1924 and increased at a yearly rate of about 0.6 Mgal/d (2.3 Ml/d) until 1942. From 1943 to 1962, pumpage averaged about 11.5 Mgal/d (43.5 Ml/d), then was reduced as MLGW (Memphis Light, Gas and Water Division) discontinued wells that became unserviceable. MLGW ceased pumping from the aquifer in 1974, and pumpage from the remaining industrial wells in Shelby County in 1975 was 4.4 Mgal/d (16.6 Ml/d). Water levels in the Fort Pillow Sand generally have risen since 1963. Water l evels in the aquifers in the Memphis area fluctuate inversely with changes in pumping. Analysis of observation-well and pumpage data indicates that local water levels can be altered by changing the pumping rates or by varying the areal distribution of pumping.

Trellises and Trellis-Based Decoding Algorithms for Linear Block Codes. Part 3; The Map and Related Decoding Algirithms

NASA Technical Reports Server (NTRS)

Lin, Shu; Fossorier, Marc

1998-01-01

In a coded communication system with equiprobable signaling, MLD minimizes the word error probability and delivers the most likely codeword associated with the corresponding received sequence. This decoding has two drawbacks. First, minimization of the word error probability is not equivalent to minimization of the bit error probability. Therefore, MLD becomes suboptimum with respect to the bit error probability. Second, MLD delivers a hard-decision estimate of the received sequence, so that information is lost between the input and output of the ML decoder. This information is important in coded schemes where the decoded sequence is further processed, such as concatenated coding schemes, multi-stage and iterative decoding schemes. In this chapter, we first present a decoding algorithm which both minimizes bit error probability, and provides the corresponding soft information at the output of the decoder. This algorithm is referred to as the MAP (maximum aposteriori probability) decoding algorithm.

Elasticity of Pargasite Amphibole: A Hydrous Phase at Mid Lithospheric Discontinuity

NASA Astrophysics Data System (ADS)

Peng, Y.; Mookherjee, M.

2017-12-01

Mid Lithospheric Discontinuity (MLD) is characterized by a low shear wave velocity ( 3 to 10 %). In cratons, the depth of MLD varies between 80 and 100 km. The reduction of the shear wave velocity at MLD is similar to what is observed in the lithosphere-asthenosphere boundary (LAB). Such low velocity at MLD could be caused by partial melting, temperature induced grain boundary sliding, changes in the elastic anisotropy, and/or metasomatism which may lead to the formation of hydrous phases including mica and amphibole. Thus, it is clear that in order to assess the role of metasomatism at MLD, we need better constraints on the elasticity of hydrous phases. However, such elasticity data are scarce. In this study, we explore elasticity of pargasite amphibole [NaCa2(Mg4Al)(Si6Al2)O22(OH)2] using density functional theory (DFT) with local density approximation (LDA) and generalized gradient approximation (GGA). We find that the pressure-volume results can be adequately described by a finite strain equation with the bulk modulus, K0 being 102 and 85 GPa for LDA and GGA respectively. We also determined the full elastic constant tensor (Cij) using the finite difference method. The bulk modulus, K0 determined from the full elastic constant tensor is 104 GPa for LDA and 87 GPa for GGA. The shear modulus, G0 determined from the full elastic constant tensor is 64 GPa for LDA and 58 GPa for GGA. The bulk and shear moduli predicted with LDA are 5 and 1 % stiffer than the recent results [1]. In contrast, the bulk and shear moduli predicted with GGA are 12 and 10 % softer compared to the recent results [1]. The full elastic constant tensor for pargasite shows significant anisotropy. For instance, LDA predicts compressional (AVP) and shear (AVS) wave anisotropy of 22 and 20 % respectively. At higher pressure, elastic moduli stiffen. However, temperature is likely to have an opposite effect on the elasticity and this remains largely unknown for pargasite. Compared to the major mantle minerals, pargasite has softer elastic constants and significant anisotropy and may explain the reduction in shear wave velocity at MLD. Reference: [1] Brown, J. M., Abramson, E. H.,2016, Phys. Earth Planet. Int., 261, 161-171. Acknowledgement: This work is supported by US NSF award EAR 1639552.

WE-AB-202-02: Incorporating Regional Ventilation Function in Predicting Radiation Fibrosis After Concurrent Chemoradiotherapy for Lung Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lan, F; Jeudy, J; Tseng, H

Purpose: To investigate the incorporation of pre-therapy regional ventilation function in predicting radiation fibrosis (RF) in stage III non-small-cell lung cancer (NSCLC) patients treated with concurrent thoracic chemoradiotherapy. Methods: 37 stage III NSCLC patients were retrospectively studied. Patients received one cycle of cisplatin-gemcitabine, followed by two to three cycles of cisplatin-etoposide concurrently with involved-field thoracic radiotherapy between 46 and 66 Gy (2 Gy per fraction). Pre-therapy regional ventilation images of the lung were derived from 4DCT via a density-change-based image registration algorithm with mass correction. RF was evaluated at 6-months post-treatment using radiographic scoring based on airway dilation and volumemore » loss. Three types of ipsilateral lung metrics were studied: (1) conventional dose-volume metrics (V20, V30, V40, and mean-lung-dose (MLD)), (2) dose-function metrics (fV20, fV30, fV40, and functional mean-lung-dose (fMLD) generated by combining regional ventilation and dose), and (3) dose-subvolume metrics (sV20, sV30, sV40, and subvolume mean-lung-dose (sMLD) defined as the dose-volume metrics computed on the sub-volume of the lung with at least 60% of the quantified maximum ventilation status). Receiver operating characteristic (ROC) curve analysis and logistic regression analysis were used to evaluate the predictability of these metrics for RF. Results: In predicting airway dilation, the area under the ROC curve (AUC) values for (V20, MLD), (fV20, fMLD), and (sV20, and sMLD) were (0.76, 0.70), (0.80, 0.74) and (0.82, 0.80), respectively. The logistic regression p-values were (0.09, 0.18), (0.02, 0.05) and (0.004, 0.006), respectively. With regard to volume loss, the corresponding AUC values for these metrics were (0.66, 0.57), (0.67, 0.61) and (0.71, 0.69), and p-values were (0.95, 0.90), (0.43, 0.64) and (0.08, 0.12), respectively. Conclusion: The inclusion of regional ventilation function improved predictability of radiation fibrosis. Dose-subvolume metrics provided a promising method for incorporating functional information into the conventional dose-volume parameters for outcome assessment.« less

Effect of Fill Temperature on Clostridium botulinum Type A Toxin Activity during the Hot Filling of Juice Bottles.

PubMed

Skinner, Guy E; Fleischman, Gregory J; Balster, Fran; Reineke, Karl; Reddy, N Rukma; Larkin, John W

2015-08-01

The potential threat of terrorist attacks against the United States food supply using neurotoxin produced by Clostridium botulinum (BoNT) has resulted in the need for studying the effect of various food process operations on the bioavailability of this toxin. The objective of this study was to evaluate C. botulinum type A neurotoxin bioavailability after a simulated hot fill juice bottling operation. C. botulinum type A acid mud toxin (∼10(6) mouse lethal dose [MLD50]/ml) was deposited into juice bottles at an experimentally determined fastest cooling spot. Bottles (12 or 20 oz [355 and 592 ml]) were filled with either apple juice or an orange drink, at 80 or 85°C, in either upright or inverted orientations. Toxicity of the juice was evaluated as a function of holding time (1 to 2 min) by the mouse bioassay. The fastest cooling point in the upright orientation was determined to be at a bottle's bottom rim. In the inverted orientation, the fastest cooling point was in the bottle cap region. With respect to these two points, the upright bottle cooled faster than the inverted bottle, which was reflected in a higher inactivation of BoNT in the latter. For the orange drink (pH 2.9) toxicity was reduced by 0.5 × 10(6) MLD50/ml to a nondetectable level after 1 min in all bottle sizes, orientations, and temperatures as measured by the mouse bioassay. This indicates that there was at least a 0.5 × 10(6) MLD50/ml reduction in activity. Inactivation in apple juice (pH 4.0), to the same degree as in the orange drink, was found only for the inverted orientation at 85°C. Complete inactivation in apple juice for all conditions was found at a lower added toxin level of 0.25 × 10(5) MLD50/ml. In general, bottle inversion and filling at 85°C provided complete inactivation of BoNT to the 0.5 × 10(6) MLD50/ml level. All experiments resulted in the inactivation of 2.5 × 10(4) MLD50/ml of BoNT regardless of juice type, fill temperature, or bottle orientation and size.

Acute Toxicity and Efficacy of Current Medical Countermeasures against VM in Guinea Pigs: A Comparison to VX and VR

DTIC Science & Technology

2013-05-01

and diazepam with and without pretreatment with pyridostigmine bromide . The 24 hr median lethal dose (MLD) of VM was determined using a sequential... pyridostigmine bromide . The 24 hr median lethal dose (MLD) of VM was determined using a sequential stage approach. The efficacy of medical...with and without pyridostigmine bromide (PB) pretreatment against lethal intoxication with VM, VR or VX. Methods Animals: Adult male Hartley

A Non-Fickian Mixing Model for Stratified Turbulent Flows

DTIC Science & Technology

2013-09-30

lateral gradients in the mixed layer, indicative of surface fronts, and with the magnitude of mixed layer depth MLD. Direct testing with our results shows...both are induced by atmospheric forcing. In our case, atmospheric fluxes and wind forcing are still the cause of SM occurrence, but mostly through their...California upwelling simulations, where MLD did not change significantly between HR and LR simulations. As suggested by Capet et al. (2008b), this is likely

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lemaire, Paul C.; Oldham, Christopher J.; Parsons, Gregory N., E-mail: gnp@ncsu.edu

Molecular layer deposition (MLD) of “metalcones,” including alucone, zincone, titanicone, and others, involves self-limiting half-reactions between organic and organometallic (or metal-halide) reactants. Studies have typically focused on metal precursors reacting with ethylene glycol or glycerol to form the films' polymeric O-M-O-(CH{sub x}){sub y}-O-M-O repeat units. The authors report new MLD materials that incorporate tertiary amine groups into the organic linkage. Specifically, reacting triethanolamine (TEA) with either trimethylaluminum or titanium tetrachloride produces TEA-alucone (Al-TEA) and TEA-titanicone (Ti-TEA), respectively, and the amine group leads to unique physical and optical properties. Fourier-transform infrared (FTIR) analysis confirms that the films have prominent C-H, C-N,more » and M-O-C peaks, consistent with the expected bond structure. When exposed to vapors, including water, alcohol, or ammonia, the Ti-TEA films changed their visible color within minutes and increased physical thickness by >35%. The Al-TEA showed significantly less response. X-ray photoelectron spectroscopy and FTIR suggest that HCl generated during MLD coordinates to the amine forming a quaternary ammonium salt that readily binds adsorbates via hydrogen bonding. The visible color change is reversible, and ellipsometry confirms that the color change results from vapor absorption. The unique absorptive and color-changing properties of the TEA-metalcone films point to new possible applications for MLD materials in filtration, chemical absorption, and multifunctional chemical separations/sensing device systems.« less

Interannual variability of Indian Ocean subtropical mode water subduction rate

NASA Astrophysics Data System (ADS)

Ma, Jie; Lan, Jian

2017-06-01

The interannual variation of Indian Ocean subtropical mode water (IOSTMW) subduction rate in the Southwest Indian Ocean from 1980 to 2007 is investigated in this paper based on Simple Ocean Data Assimilation (SODA) outputs. Climatology of subduction rate exceeds 75 m/year in the IOSTMW formation area. The renewal time of permanent pycnocline water mass based on the subduction rate is calculated for each density class: 3-6 years for IOSTMW (25.8 < σ θ < 26.2 kg m-3). Subduction rate in the Southwest Indian Ocean subtropical gyre exhibits a great year-to-year variability. This interannual variations of the IOSTMW subduction rate is primarily dominated by the lateral induction term, associated with the interannual variations of strong meridional gradient of winter mixed layer depth (MLD). The slope of the mixed layer depth in the mode water is closely linked to the large variations of deep late winter MLD in the mid-latitudes and negligible variations of shallow winter MLD in lower latitudes. It is further identified that the interannual variation of late winter MLD in this area is largely controlled by the latent and sensible heat flux components. The water volume of the permanent pycnocline in the IOSTMW distribution area is also found to show a significant interannual variability, and it is well correlated with the interannual variation of subduction rate.

Gastrointestinal blood loss induced by three different non-steroidal anti-inflammatory drugs.

PubMed

Bidlingmaier, A; Hammermaier, A; Nagyiványi, P; Pabst, G; Waitzinger, J

1995-04-01

A clinical study was performed on 18 healthy volunteers to compare the gastrointestinal daily blood loss induced by oral intake of three different non-steroidal anti-inflammatory drugs, lysine clonixinate (CAS 55837-30-4), ibuprofen (CAS 15687-27-1) and acetylsalicylic acid (CAS 50-78-2 ASA). For quantitative determination of gastrointestinal blood loss, autologous erythrocytes were radiolabelled in vitro with 51Cr and reinfused at study start. The amount of radioactivity excreted in faeces was measured during a placebo baseline phase of three days, a treatment phase of five days with thrice daily dosing of ASA, ibuprofen or lysine clonixinate and a subsequent wash-out phase of five days. The highest increase of mean daily blood loss over baseline was observed after treatment with ASA (+ 1.66 ml/d versus baseline). Treatment with ibuprofen led to an increase of mean daily blood loss by + 0.52 ml/d. During treatment with lysine clonixinate the mean increase of daily blood loss was +0.32 ml/d versus baseline. In the ibuprofen and lysine clonixinate treatment groups the values of mean daily blood loss decreased during the wash-out phase with respect to the verum phase, whereas the mean daily blood loss during the wash-out phase after treatment with ASA even increased in comparison to the verum phase (mean daily blood loss: +2.07 ml/d versus baseline.

Modelling study of sea breezes in a complex coastal environment

NASA Astrophysics Data System (ADS)

Cai, X.-M.; Steyn, D. G.

This study investigates a mesoscale modelling of sea breezes blowing from a narrow strait into the lower Fraser valley (LFV), British Columbia, Canada, during the period of 17-20 July, 1985. Without a nudging scheme in the inner grid, the CSU-RAMS model produces satisfactory wind and temperature fields during the daytime. In comparison with observation, the agreement indices for surface wind and temperature during daytime reach about 0.6 and 0.95, respectively, while the agreement indices drop to 0.4 at night. In the vertical, profiles of modelled wind and temperature generally agree with tethersonde data collected on 17 and 19 July. The study demonstrates that in late afternoon, the model does not capture the advection of an elevated warm layer which originated from land surfaces outside of the inner grid. Mixed layer depth (MLD) is calculated from model output of turbulent kinetic energy field. Comparison of MLD results with observation shows that the method generates a reliable MLD during the daytime, and that accurate estimates of MLD near the coast require the correct simulation of wind conditions over the sea. The study has shown that for a complex coast environment like the LFV, a reliable modelling study depends not only on local surface fluxes but also on elevated layers transported from remote land surfaces. This dependence is especially important when local forcings are weak, for example, during late afternoon and at night.

Enzymatic characterization of novel arylsulfatase A variants using human arylsulfatase A-deficient immortalized mesenchymal stromal cells.

PubMed

Böhringer, Judith; Santer, René; Schumacher, Neele; Gieseke, Friederike; Cornils, Kerstin; Pechan, Maria; Kustermann-Kuhn, Birgit; Handgretinger, Rupert; Schöls, Ludger; Harzer, Klaus; Krägeloh-Mann, Ingeborg; Müller, Ingo

2017-11-01

Metachromatic leukodystrophy (MLD) is an autosomal-recessive lysosomal storage disease caused by mutations in the ARSA gene leading to arylsulfatase A (ARSA) deficiency and causing sulfatide accumulation. Main symptoms of the disease are progressive demyelination, neurological dysfunction, and reduced life expectancy. To date, more than 200 different ARSA variants have been reported in MLD patients. Here, we report the biochemical characterization of seven novel pathogenic variants (c.98T > C, c.195delC, c.229G > C, c.545C > G, c.674A > G, c.852T > A, and c.1274A > G), which were found when sequencing a cohort of 31 German MLD families. For that purpose, the ARSA cDNAs carrying the respective mutations inserted by site-directed mutagenesis were cloned into a MigR1 (MSCV, IRES, GFP, retrovirus-1) vector. The constructs were overexpressed using retroviral gene transfer in immortalized, human multipotent mesenchymal stromal cells prepared from a patient deficient in ARSA activity (late infantile MLD). In this novel ARSA -/- cell system, the seven ARSA mutants showed ARSA activity of less than 10% when compared with wild type, which is evidence for the pathogenicity of all seven variants. In conclusion, the system of ARSA -/- -immortalized MSC turned out to be a helpful novel tool for the biochemical characterization of ARSA variants. © 2017 Wiley Periodicals, Inc.

Ergonovine-induced changes of coronary artery diameter in patients with nonsignificant coronary artery stenosis : relation with lipid profile.

PubMed

Nedeljkovic, Milan A; Ostojic, Miodrag C; Beleslin, Branko D; Nedeljkovic, Ivana; Milic, Natasa; Vukcevic, Vladan; Stojkovic, Sinisa; Saponjski, Jovica; Orlic, Dejan; Djordjevic-Dikic, Ana; Stepanovic, Jelena; Giga, Vojislav; Petrasinovic, Zorica; Arandjelovic, Aleksandra; Beleslin, Biljana; Kanjuh, Vladimir

2007-06-01

Serum cholesterol is positively associated with the risk of developing coronary heart disease. The aim of this study was to determine the relation between response of coronary arteries to ergonovine provocation and lipid profile in patients with nonsignificant coronary artery disease. 105 patients (46 male, 59 female, mean age 52 +/- 8 years) with chest pain syndrome and nonsignificant coronary artery stenosis (< 50% diameter stenosis) were analyzed. Ergonovine test was performed at the end of diagnostic catheterization. Coronary spasm was defined as total or near total obstruction of the coronary artery. By quantitative coronary arteriography, changes of minimal luminal diameter (MLD) during ergonovine provocation were evaluated. Total cholesterol, LDL and HDL cholesterol, and triglycerides were measured. There was a significant negative correlation between resting MLD and LDL cholesterol (r = -0.215; p = 0.034), and a significant positive correlation between MLD decrease provoked by ergonovine and total cholesterol (r = 0.275; p = 0.006), as well as LDL cholesterol (r = 0.284; p = 0.004), but not for HDL cholesterol and triglycerides (p = NS [not significant]). In patients with nonsignificant coronary artery stenosis evaluated by ergonovine provocation, there was not only a significant negative correlation between MLD and LDL cholesterol, but also a positive correlation between coronary vasoconstriction induced by ergonovine provocation and both total and LDL cholesterol.

Status of Muslim Immigrants' Children with Learning Difficulties in Vienna

ERIC Educational Resources Information Center

Mohsin, M. Naeem; Shabbir, Muhammad; Saeed, Wizra; Mohsin, M. Saleem

2013-01-01

The study was conducted to know the status of Muslim immigrants' children with learning difficulties and importance of parents' involvement for the education whose children are with learning difficulties, and the factors responsible for the learning difficulties among immigrants' children. There were 81 immigrant children with learning…

What Do Romanian Teachers Know about Learning Difficulties

ERIC Educational Resources Information Center

Pop, Cristina Florina; Ciascai, Liliana

2013-01-01

There is a growing concern for students with learning difficulties and teachers are responsible for identifying and helping these students. The present study aims to explore the teachers' knowledge of manifestations, causes and types of learning difficulties, necessary to diagnose, prevent or remedy learning difficulties. The participants involved…

Method of predicting the mean lung dose based on a patient's anatomy and dose-volume histograms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zawadzka, Anna, E-mail: a.zawadzka@zfm.coi.pl; Nesteruk, Marta; Department of Radiation Oncology, University Hospital Zurich and University of Zurich, Zurich

The aim of this study was to propose a method to predict the minimum achievable mean lung dose (MLD) and corresponding dosimetric parameters for organs-at-risk (OAR) based on individual patient anatomy. For each patient, the dose for 36 equidistant individual multileaf collimator shaped fields in the treatment planning system (TPS) was calculated. Based on these dose matrices, the MLD for each patient was predicted by the homemade DosePredictor software in which the solution of linear equations was implemented. The software prediction results were validated based on 3D conformal radiotherapy (3D-CRT) and volumetric modulated arc therapy (VMAT) plans previously prepared formore » 16 patients with stage III non–small-cell lung cancer (NSCLC). For each patient, dosimetric parameters derived from plans and the results calculated by DosePredictor were compared. The MLD, the maximum dose to the spinal cord (D{sub max} {sub cord}) and the mean esophageal dose (MED) were analyzed. There was a strong correlation between the MLD calculated by the DosePredictor and those obtained in treatment plans regardless of the technique used. The correlation coefficient was 0.96 for both 3D-CRT and VMAT techniques. In a similar manner, MED correlations of 0.98 and 0.96 were obtained for 3D-CRT and VMAT plans, respectively. The maximum dose to the spinal cord was not predicted very well. The correlation coefficient was 0.30 and 0.61 for 3D-CRT and VMAT, respectively. The presented method allows us to predict the minimum MLD and corresponding dosimetric parameters to OARs without the necessity of plan preparation. The method can serve as a guide during the treatment planning process, for example, as initial constraints in VMAT optimization. It allows the probability of lung pneumonitis to be predicted.« less

Calculation of Cumulative Distributions and Detection Probabilities in Communications and Optics.

DTIC Science & Technology

1986-03-31

result, Figure 3.1 shows the additional SNR required (often called the CFAR loss) for the MLD, CMLD , and OSD in a multiple target environment to...Notice that although the CFAR loss increases with INR for the MLD, the CMLD and OSD have a bounded loss as the INR + w. These results have been more...false-alarm rate ( CFAR ) when the background noise level is unknown. In Section 2 we described the application of saddlepoint integration techniques to

Assessing College-Level Learning Difficulties and "At Riskness" for Learning Disabilities and ADHD: Development and Validation of the Learning Difficulties Assessment

ERIC Educational Resources Information Center

Kane, Steven T.; Walker, John H.; Schmidt, George R.

2011-01-01

This article describes the development and validation of the "Learning Difficulties Assessment" (LDA), a normed and web-based survey that assesses perceived difficulties with reading, writing, spelling, mathematics, listening, concentration, memory, organizational skills, sense of control, and anxiety in college students. The LDA is designed to…

Master Logic Diagram: An Approach to Identify Initiating Events of HTGRs

NASA Astrophysics Data System (ADS)

Purba, J. H.

2018-02-01

Initiating events of a nuclear power plant being evaluated need to be firstly identified prior to applying probabilistic safety assessment on that plant. Various types of master logic diagrams (MLDs) have been proposedforsearching initiating events of the next generation of nuclear power plants, which have limited data and operating experiences. Those MLDs are different in the number of steps or levels and different in the basis for developing them. This study proposed another type of MLD approach to find high temperature gas cooled reactor (HTGR) initiating events. It consists of five functional steps starting from the top event representing the final objective of the safety functions to the basic event representing the goal of the MLD development, which is an initiating event. The application of the proposed approach to search for two HTGR initiating events, i.e. power turbine generator trip and loss of offsite power, is provided. The results confirmed that the proposed MLD is feasiblefor finding HTGR initiating events.

Clinical verification of a theory for predicting side branch stenosis after main vessel stenting in coronary bifurcation lesions.

PubMed

Vassilev, Dobrin; Gil, Robert

2008-12-01

To verify in a clinical scenario a theory for predicting side branch (SB) stenosis after main vessel stent implantation in coronary bifurcation lesions. Many unresolved issues remain regarding SB compromise when the parent vessel is stented. Bifurcation lesions (all Medina types) were subjected to angiographic analysis to determine the angle, defined as alpha, between the axes of the parent vessel and the SB. Using the prediction that the percent diameter stenosis (%DS) is equal to the cosine of angle alpha and relating it to a formula to determine the minimal lumen diameter (MLD) led to the following equation: MLD = ds x (1 -cos alpha); ds refers to the diameter of the SB. The predicted and observed SB stenosis values following angiography were compared. Fifty-two patients with 57 lesions were included in the analysis. Patient demographics and characteristics were similar to those in previous studies. There was a high coefficient of determination between the predicted and observed values of %DS (r(2)= 0.82, P < 0.001) and MLD (r(2)= 0.86, P < 0.001). We determined a cutoff value of 70% for predicted %DS for SB closure. When using multivariate regression analysis, the only predictor of SB ostial stenosis after stenting was alpha angle, whereas the predictors of MLD included the angle alpha and the RVD of the SB. Our analysis shows that the most powerful independent predictor of SB compromise is a new variable angle alpha.

Return-to-play outcomes after microscopic lumbar diskectomy in professional athletes.

PubMed

Watkins, Robert G; Hanna, Robert; Chang, David; Watkins, Robert G

2012-11-01

It has been shown a microscopic lumbar diskectomy (MLD) is effective in getting professional athletes back to their sport after a herniated nucleus pulposus (HNP). There is a need for more information on the time it takes professional athletes to return after surgery. To determine average time for return to play and success in returning to play for professional athletes undergoing MLD. Case series; Level of evidence, 4. Between 1996 and 2010, the senior authors treated 171 professional athletes for lumbar HNP. A retrospective review was performed using patient charts, operative reports, team medical records, and internet search. Eighty-five patients were treated with MLD, and 86 patients were treated nonoperatively. This study focused on the return to play of the operatively treated patients. Primary outcome measures were return rate and average return time, considering only patients whose sport is in season at specific postoperative time points. Of surgically treated patients, 89.3% returned to sport. The average time it took operative patients to return to their sport (return time) was 5.8 months. Progressive return data for surgically treated patients showed the percentage of athletes who returned increased from 50% at 3 months to 72% at 6 months to 77% at 9 months and 84% at 12 months. The chance a player returns to play after MLD is 50% at 3 months, 72% at 6 months, 77% at 9 months, and 84% at 12 months. The overall chance of returning to play at any point is 89%.

The protective effect of habitual tea consumption on hypertension.

PubMed

Yang, Yi-Ching; Lu, Feng-Hwa; Wu, Jin-Shang; Wu, Chih-Hsing; Chang, Chih-Jen

2004-07-26

Tea has long been believed to possess hypotensive effects in popular Chinese medicine. However, conflicting results have been shown among human trials and animal studies on the relation between tea consumption and blood pressure. Epidemiological evidence about the long-term effect of tea on hypertensive risk is also inconsistent. We examined the effect of tea drinking, measured in detail for the past decades, on the risk of newly diagnosed hypertension in 1507 subjects (711 men and 796 women), 20 years or older, who did not have a hypertensive history during 1996 in Taiwan. Six hundred subjects (39.8%) were habitual tea drinkers, defined by tea consumption of 120 mL/d or more for at least 1 year. Compared with nonhabitual tea drinkers, the risk of developing hypertension decreased by 46% for those who drank 120 to 599 mL/d and was further reduced by 65% for those who drank 600 mL/d or more after carefully adjusting for age, sex, socioeconomic status, family history of hypertension, body mass index, waist-hip ratio, lifestyle factors (total physical activity, high sodium intake, cigarette smoking, alcohol consumption, and coffee drinking), and dietary factors (vegetable, fruit, unrefined grain, fish, milk, visible-fat food, and deep fried food intake). However, tea consumption for more than 1 year was not associated with a further reduction of hypertension risk. Habitual moderate strength green or oolong tea consumption, 120 mL/d or more for 1 year, significantly reduces the risk of developing hypertension in the Chinese population.

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, Yang; Piper, Daniela M.; Gu, Meng

Surface modification of silicon nanoparticle via molecular layer deposition (MLD) has been recently proved to be an effective way for dramatically enhancing the cyclic performance in lithium ion batteries. However, the fundamental mechanism as how this thin layer of coating function is not known, which is even complicated by the inevitable presence of native oxide of several nanometers on the silicon nanoparticle. Using in-situ TEM, we probed in detail the structural and chemical evolution of both uncoated and coated silicon particles upon cyclic lithiation/delithation. We discovered that upon initial lithiation, the native oxide layer converts to crystalline Li2O islands, whichmore » essentially increases the impedance on the particle, resulting in ineffective lithiation/delithiation, and therefore low coulombic efficiency. In contrast, the alucone MLD coated particles show extremely fast, thorough and highly reversible lithiation behaviors, which are clarified to be associated with the mechanical flexibility and fast Li+/e- conductivity of the alucone coating. Surprisingly, the alucone MLD coating process chemically changes the silicon surface, essentially removing the native oxide layer and therefore mitigates side reaction and detrimental effects of the native oxide. This study provides a vivid picture of how the MLD coating works to enhance the coulombic efficiency and preserve capacity and clarifies the role of the native oxide on silicon nanoparticles during cyclic lithiation and delithiation. More broadly, this work also demonstrated that the effect of the subtle chemical modification of the surface during the coating process may be of equal importance as the coating layer itself.« less

Fan-shaped complete block on helical tomotherapy for esophageal cancer: a phantom study.

PubMed

Chang, Chiu-Han; Mok, Greta S P; Shueng, Pei-Wei; Yeh, Hsin-Pei; Shiau, An-Cheng; Tien, Hui-Ju; Lin, Chi-Ta; Wu, Tung-Hsin

2015-01-01

Radiation pneumonitis (RP) is a common complication for radiotherapy of esophageal cancer and is associated with the low dose irradiated lung volume. This study aims to reduce the mean lung dose (MLD) and the relative lung volume at 20 Gy (V 20) and at low dose region using various designs of the fan-shaped complete block (FSCB) in helical tomotherapy. Hypothetical esophageal tumor was delineated on an anthropomorphic phantom. The FSCB was defined as the fan-shaped radiation restricted area located in both lungs. Seven treatment plans were performed with nonblock design and FSCB with different fan angles, that is, from 90° to 140°, with increment of 10°. The homogeneous index, conformation number, MLD, and the relative lung volume receiving more than 5, 10, 15, and 20 Gy (V 5, V 10, V 15, and V 20) were determined for each treatment scheme. There was a substantial reduction in the MLD, V 5, V 10, V 15, and V 20 when using different types of FSCB as compared to the nonblock design. The reduction of V 20, V 15, V 10, and V 5 was 6.3%-8.6%, 16%-23%, 42%-57%, and 42%-66% for FSCB 90°-140°, respectively. The use of FSCB in helical tomotherapy is a promising method to reduce the MLD, V 20, and relative lung volume in low dose region, especially in V 5 and V 10 for esophageal cancer.

A Meta-Analysis of Working Memory Deficits in Children with Learning Difficulties: Is There a Difference between Verbal Domain and Numerical Domain?

ERIC Educational Resources Information Center

Peng, Peng; Fuchs, Douglas

2016-01-01

Children with learning difficulties suffer from working memory (WM) deficits. Yet the specificity of deficits associated with different types of learning difficulties remains unclear. Further research can contribute to our understanding of the nature of WM and the relationship between it and learning difficulties. The current meta-analysis…

Students' performance in phonological awareness, rapid naming, reading, and writing.

PubMed

Capellini, Simone Aparecida; Lanza, Simone Cristina

2010-01-01

phonological awareness, rapid naming, reading and writing in students with learning difficulties of a municipal public school. to characterize and compare the performance of students from public schools with and without learning difficulties in phonological awareness, rapid naming, reading and writing. participants were 60 students from the 2nd to the 4th grades of municipal public schools divided into 6 groups. Each group was composed by 10 students, being 3 groups of students without learning difficulties and 3 groups with students with learning difficulties. As testing procedure phonological awareness, rapid automatized naming, oral reading and writing under dictation assessments were used. the results highlighted the better performance of students with no learning difficulties. Students with learning difficulties presented a higher ratios considering time/speed in rapid naming tasks and, consequently, lower production in activities of phonological awareness and reading and writing, when compared to students without learning difficulties. students with learning difficulties presented deficits when considering the relationship between naming and automatization skills, and among lexical access, visual discrimination, stimulus frequency use and competition in using less time for code naming, i.e. necessary for the phoneme-grapheme conversion process required in the reading and writing alphabetic system like the Portuguese language.

Estimation of Surface Seawater Fugacity of Carbon Dioxide Using Satellite Data and Machine Learning

NASA Astrophysics Data System (ADS)

Jang, E.; Im, J.; Park, G.; Park, Y.

2016-12-01

The ocean controls the climate of Earth by absorbing and releasing CO2 through the carbon cycle. The amount of CO2 in the ocean has increased since the industrial revolution. High CO2 concentration in the ocean has a negative influence to marine organisms and reduces the ability of absorbing CO2 in the ocean. This study estimated surface seawater fugacity of CO2 (fCO2) in the East Sea of Korea using Geostationary Ocean Color Imager (GOCI) and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data, and Hybrid Coordinate Ocean Model (HYCOM) reanalysis data. GOCI is the world first geostationary ocean color observation satellite sensor, and it provides 8 images with 8 bands hourly per day from 9 am to 4 pm at 500m resolution. Two machine learning approaches (i.e., random forest and support vector regression) were used to model fCO2 in this study. While most of the existing studies used multiple linear regression to estimate the pressure of CO2 in the ocean, machine learning may handle more complex relationship between surface seawater fCO2 and ocean parameters in a dynamic spatiotemporal environment. Five ocean related parameters, colored dissolved organic matter (CDOM), chlorophyll-a (chla), sea surface temperature (SST), sea surface salinity (SSS), and mixed layer depth (MLD), were used as input variables. This study examined two schemes, one with GOCI-derived products and the other with MODIS-derived ones. Results show that random forest performed better than support vector regression regardless of satellite data used. The accuracy of GOCI-based estimation was higher than MODIS-based one, possibly thanks to the better spatiotemporal resolution of GOCI data. MLD was identified the most contributing parameter in estimating surface seawater fCO2 among the five ocean related parameters, which might be related with an active deep convection in the East Sea. The surface seawater fCO2 in summer was higher in general with some spatial variation than the other seasons because of higher SST.

Effects of Persuasive Designed Courseware on Children with Learning Difficulties in Learning Malay Language Subject

ERIC Educational Resources Information Center

Ng, Kien Heng; Bakri, Aryati; Rahman, Azizah Abdul

2016-01-01

The effects of courseware learning for children with learning difficulties have been studied over the years. Educational courseware is very common nowadays as a teaching tool for children's early education. However, most of the coursewares are designed for children with normal learning ability. Special children who face difficulty in the learning…

Effects of a specific blend of essential oils on apparent nutrient digestion, rumen fermentation and rumen microbial populations in sheep fed a 50:50 alfalfa hay:concentrate diet

PubMed Central

Khateri, N.; Azizi, O.; Jahani-Azizabadi, H.

2017-01-01

Objective An experiment was conducted to investigate the effects of a specific mixture of essential oils (MEO), containing thyme, clove and cinnamon EO, on rumen microbial fermentation, nutrient apparent digestibility and blood metabolites in fistulated sheep. Methods Six sheep fitted with ruminal fistulas were used in a repeated measurement design with two 24-d periods to investigate the effect of adding MEO at 0 (control), 0.8, and 1.6 mL/d on apparent nutrient digestibility, rumen fermentation characteristics, rumen microbial population and blood chemical metabolites. Animals were fed with a 50:50 alfalfa hay:concentrate diet. Results Ruminal pH, total volatile fatty acids (VFA) concentration, molar proportion of individual VFA, acetate: propionate ratio and methane production were not affected with MEO. Relative to the control, Small peptides plus amino acid nitrogen and large peptides nitrogen concentration in rumen fluid were not affected with MEO supplementation; while, rumen fluid ammonia nitrogen concentration at 0 and 6 h after morning feeding in sheep fed with 1.6 mL/d of MEO was lower (p<0.05) compared to the control and 0.8 mL/d of MEO. At 0 h after morning feeding, ammonia nitrogen concentration was higher (p<0.05) in sheep fed 0.8 mL/d of MEO relative to 1.6 mL/d and control diet. Ruminal protozoa and hyper ammonia producing (HAP) bacteria counts were not affected by addition of MEO in the diet. Relative to the control, no changes were observed in the red and white blood cells, hemoglobin, hematocrit, glucose, beta-hydroxybutyric acid, cholesterol, total protein, albumin, blood urea nitrogen and aspartate aminotransferase and alanine aminotransferase concentration. Apparent total tract digestibility of dry matter, crude proten, organic matter, and neutral detergent fiber were not influenced by MEO supplementation. Conclusion The results of the present study suggested that supplementation of MEO may have limited effects on apparent nutrient digestibility, ruminal fermentation and protozoa and HAP bacteria count, blood cells and metabolites. PMID:28249376

Delineation of marine ecosystem zones in the northern Arabian Sea during winter

NASA Astrophysics Data System (ADS)

Shalin, Saleem; Samuelsen, Annette; Korosov, Anton; Menon, Nandini; Backeberg, Björn C.; Pettersson, Lasse H.

2018-03-01

The spatial and temporal variability of marine autotrophic abundance, expressed as chlorophyll concentration, is monitored from space and used to delineate the surface signature of marine ecosystem zones with distinct optical characteristics. An objective zoning method is presented and applied to satellite-derived Chlorophyll a (Chl a) data from the northern Arabian Sea (50-75° E and 15-30° N) during the winter months (November-March). Principal component analysis (PCA) and cluster analysis (CA) were used to statistically delineate the Chl a into zones with similar surface distribution patterns and temporal variability. The PCA identifies principal components of variability and the CA splits these into zones based on similar characteristics. Based on the temporal variability of the Chl a pattern within the study area, the statistical clustering revealed six distinct ecological zones. The obtained zones are related to the Longhurst provinces to evaluate how these compared to established ecological provinces. The Chl a variability within each zone was then compared with the variability of oceanic and atmospheric properties viz. mixed-layer depth (MLD), wind speed, sea-surface temperature (SST), photosynthetically active radiation (PAR), nitrate and dust optical thickness (DOT) as an indication of atmospheric input of iron to the ocean. The analysis showed that in all zones, peak values of Chl a coincided with low SST and deep MLD. The rate of decrease in SST and the deepening of MLD are observed to trigger the algae bloom events in the first four zones. Lagged cross-correlation analysis shows that peak Chl a follows peak MLD and SST minima. The MLD time lag is shorter than the SST lag by 8 days, indicating that the cool surface conditions might have enhanced mixing, leading to increased primary production in the study area. An analysis of monthly climatological nitrate values showed increased concentrations associated with the deepening of the mixed layer. The input of iron seems to be important in both the open-ocean and coastal areas of the northern and north-western parts of the northern Arabian Sea, where the seasonal variability of the Chl a pattern closely follows the variability of iron deposition.

Combined Ventilation and Perfusion Imaging Correlates With the Dosimetric Parameters of Radiation Pneumonitis in Radiation Therapy Planning for Lung Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kimura, Tomoki, E-mail: tkkimura@hiroshima-u.ac.jp; Doi, Yoshiko; Nakashima, Takeo

2015-11-15

Purpose: The purpose of this study was to prospectively investigate clinical correlations between dosimetric parameters associated with radiation pneumonitis (RP) and functional lung imaging. Methods and Materials: Functional lung imaging was performed using four-dimensional computed tomography (4D-CT) for ventilation imaging, single-photon emission computed tomography (SPECT) for perfusion imaging, or both (V/Q-matched region). Using 4D-CT, ventilation imaging was derived from a low attenuation area according to CT numbers below different thresholds (vent-860 and -910). Perfusion imaging at the 10th, 30th, 50th, and 70th percentile perfusion levels (F10-F70) were defined as the top 10%, 30%, 50%, and 70% hyperperfused normal lung, respectively.more » All imaging data were incorporated into a 3D planning system to evaluate correlations between RP dosimetric parameters (where fV20 is the percentage of functional lung volume irradiated with >20 Gy, or fMLD, the mean dose administered to functional lung) and the percentage of functional lung volume. Radiation pneumonitis was evaluated using Common Terminology Criteria for Adverse Events version 4.0. Statistical significance was defined as a P value of <.05. Results: Sixty patients who underwent curative radiation therapy were enrolled (48 patients for non-small cell lung cancer, and 12 patients for small cell lung cancer). Grades 1, 2, and ≥3 RP were observed in 16, 44, and 6 patients, respectively. Significant correlations were observed between the percentage of functional lung volume and fV20 (r=0.4475 in vent-860 and 0.3508 in F30) or fMLD (r=0.4701 in vent-860 and 0.3128 in F30) in patients with grade ≥2 RP. F30∩vent-860 results exhibited stronger correlations with fV20 and fMLD in patients with grade ≥2 (r=0.5509 in fV20 and 0.5320 in fMLD) and grade ≥3 RP (r=0.8770 in fV20 and 0.8518 in fMLD). Conclusions: RP dosimetric parameters correlated significantly with functional lung imaging.« less

Atomic and Molecular Layer Deposition for Enhanced Lithium Ion Battery Electrodes and Development of Conductive Metal Oxide/Carbon Composites

NASA Astrophysics Data System (ADS)

Travis, Jonathan

The performance and safety of lithium-ion batteries (LIBs) are dependent on interfacial processes at the positive and negative electrodes. For example, the surface layers that form on cathodes and anodes are known to affect the kinetics and capacity of LIBs. Interfacial reactions between the electrolyte and the electrodes are also known to initiate electrolyte combustion during thermal runaway events that compromise battery safety. Atomic layer deposition (ALD) and molecular layer deposition (MLD) are thin film deposition techniques based on sequential, self-limiting surface reactions. ALD and MLD can deposit ultrathin and conformal films on high aspect ratio and porous substrates such as composite particulate electrodes in lithium-ion batteries. The effects of electrode surface modification via ALD and MLD are studied using a variety of techniques. It was found that sub-nm thick coatings of Al2O 3 deposited via ALD have beneficial effects on the stability of LIB anodes and cathodes. These same Al2O3 ALD films were found to improve the safety of graphite based anodes through prevention of exothermic solid electrolyte interface (SEI) degradation at elevated temperatures. Ultrathin and conformal metal alkoxide polymer films known as "metalcones" were grown utilizing MLD techniques with trimethylaluminum (TMA) or titanium tetrachloride (TiCl4) and organic diols or triols, such as ethylene glycol (EG), glycerol (GL) or hydroquinone (HQ), as the reactants. Pyrolysis of these metalcone films under inert gas conditions led to the development of conductive metal oxide/carbon composites. The composites were found to contain sp2 carbon using micro-Raman spectroscopy in the pyrolyzed films with pyrolysis temperatures ≥ 600°C. Four point probe measurements demonstrated that the graphitic sp2 carbon domains in the metalcone films grown using GL and HQ led to significant conductivity. The pyrolysis of conformal MLD films to obtain conductive metal oxide/carbon composite films is presented as a method for enabling non-conductive, but possibly electrochemically active materials, to be used for electrochemical applications.

What Is Literacy for Students with Severe Learning Difficulties? Exploring Conventional and Inclusive Literacy

ERIC Educational Resources Information Center

Lacey, Penny; Layton, Lyn; Miller, Carol; Goldbart, Juliet; Lawson, Hazel

2007-01-01

This paper arises from research into inclusive literacy for pupils with severe learning difficulties who do not learn to read and write conventionally. The ultimate aim of the study was to seek out examples of good practice in teaching and learning literacy that includes students with severe learning difficulties and disseminate them as widely as…

Structural basis for ribosome protein S1 interaction with RNA in trans-translation of Mycobacterium tuberculosis.

PubMed

Fan, Yi; Dai, Yazhuang; Hou, Meijing; Wang, Huilin; Yao, Hongwei; Guo, Chenyun; Lin, Donghai; Liao, Xinli

2017-05-27

Ribosomal protein S1 (RpsA), the largest 30S protein in ribosome, plays a significant role in translation and trans-translation. In Mycobacterium tuberculosis, the C-terminus of RpsA is known as tuberculosis drug target of pyrazinoic acid, which inhibits the interaction between MtRpsA and tmRNA in trans-translation. However, the molecular mechanism underlying the interaction of MtRpsA with tmRNA remains unknown. We herein analyzed the interaction of the C-terminal domain of MtRpsA with three RNA fragments poly(A), sMLD and pre-sMLD. NMR titration analysis revealed that the RNA binding sites on MtRpsA CTD are mainly located in the β2, β3 and β5 strands and the adjacent L3 loop of the S1 domain. Fluorescence experiments determined the MtRpsA CTD binding to RNAs are in the micromolar affinity range. Sequence analysis also revealed conserved residues in the mapped RNA binding region. Residues L304, V305, G308, F310, H322, I323, R357 and I358 were verified to be the key residues influencing the interaction between MtRpsA CTD and pre-sMLD. Molecular docking further confirmed that the poly(A)-like sequence and sMLD of tmRNA are all involved in the protein-RNA interaction, through charged interaction and hydrogen bonds. The results will be beneficial for designing new anti-tuberculosis drugs. Copyright © 2017 Elsevier Inc. All rights reserved.

Can we map the interannual variability of the whole upper Southern Ocean with the current database of hydrographic observations?

NASA Astrophysics Data System (ADS)

Heuzé, C.; Vivier, F.; Le Sommer, J.; Molines, J.-M.; Penduff, T.

2015-12-01

With the advent of Argo floats, it now seems feasible to study the interannual variations of upper ocean hydrographic properties of the historically undersampled Southern Ocean. To do so, scattered hydrographic profiles often first need to be mapped. To investigate biases and errors associated both with the limited space-time distribution of the profiles and with the mapping methods, we colocate the mixed-layer depth (MLD) output from a state-of-the-art 1/12° DRAKKAR simulation onto the latitude, longitude, and date of actual in situ profiles from 2005 to 2014. We compare the results obtained after remapping using a nearest neighbor (NN) interpolation and an objective analysis (OA) with different spatiotemporal grid resolutions and decorrelation scales. NN is improved with a coarser resolution. OA performs best with low decorrelation scales, avoiding too strong a smoothing, but returns values over larger areas with large decorrelation scales and low temporal resolution, as more points are available. For all resolutions OA represents better the annual extreme values than NN. Both methods underestimate the seasonal cycle in MLD. MLD biases are lower than 10 m on average but can exceed 250 m locally in winter. We argue that current Argo data should not be mapped to infer decadal trends in MLD, as all methods are unable to reproduce existing trends without creating unrealistic extra ones. We also show that regions of the subtropical Atlantic, Indian, and Pacific Oceans, and the whole ice-covered Southern Ocean, still cannot be mapped even by the best method because of the lack of observational data.

Evaluating mice lacking serum carboxylesterase as a behavioral model for nerve agent intoxication.

PubMed

Dunn, Emily N; Ferrara-Bowens, Teresa M; Chachich, Mark E; Honnold, Cary L; Rothwell, Cristin C; Hoard-Fruchey, Heidi M; Lesyna, Catherine A; Johnson, Erik A; Cerasoli, Douglas M; McDonough, John H; Cadieux, C Linn

2018-06-07

Mice and other rodents are typically utilized for chemical warfare nerve agent research. Rodents have large amounts of carboxylesterase in their blood, while humans do not. Carboxylesterase nonspecifically binds to and detoxifies nerve agent. The presence of this natural bioscavenger makes mice and other rodents poor models for studies identifying therapeutics to treat humans exposed to nerve agents. To obviate this problem, a serum carboxylesterase knockout (Es1 KO) mouse was created. In this study, Es1 KO and wild type (WT) mice were assessed for differences in gene expression, nerve agent (soman; GD) median lethal dose (MLD) values, and behavior prior to and following nerve agent exposure. No expression differences were detected between Es1 KO and WT mice in more than 34 000 mouse genes tested. There was a significant difference between Es1 KO and WT mice in MLD values, as the MLD for GD-exposed WT mice was significantly higher than the MLD for GD-exposed Es1 KO mice. Behavioral assessments of Es1 KO and WT mice included an open field test, a zero maze, a Barnes maze, and a sucrose preference test (SPT). While sex differences were observed in various measures of these tests, overall, Es1 KO mice behaved similarly to WT mice. The two genotypes also showed virtually identical neuropathological changes following GD exposure. Es1 KO mice appear to have an enhanced susceptibility to GD toxicity while retaining all other behavioral and physiological responses to this nerve agent, making the Es1 KO mouse a more human-like model for nerve agent research.

Consequences of Early Conductive Hearing Loss on Long-Term Binaural Processing.

PubMed

Graydon, Kelley; Rance, Gary; Dowell, Richard; Van Dun, Bram

The aim of the study was to investigate the long-term effects of early conductive hearing loss on binaural processing in school-age children. One hundred and eighteen children participated in the study, 82 children with a documented history of conductive hearing loss associated with otitis media and 36 controls who had documented histories showing no evidence of otitis media or conductive hearing loss. All children were demonstrated to have normal-hearing acuity and middle ear function at the time of assessment. The Listening in Spatialized Noise Sentence (LiSN-S) task and the masking level difference (MLD) task were used as the two different measures of binaural interaction ability. Children with a history of conductive hearing loss performed significantly poorer than controls on all LiSN-S conditions relying on binaural cues (DV90, p = <0.001 and SV90, p = 0.003). No significant difference was found between the groups in listening conditions without binaural cues. Fifteen children with a conductive hearing loss history (18%) showed results consistent with a spatial processing disorder. No significant difference was observed between the conductive hearing loss group and the controls on the MLD task. Furthermore, no correlations were found between LiSN-S and MLD. Results show a relationship between early conductive hearing loss and listening deficits that persist once hearing has returned to normal. Results also suggest that the two binaural interaction tasks (LiSN-S and MLD) may be measuring binaural processing at different levels. Findings highlight the need for a screening measure of functional listening ability in children with a history of early otitis media.

The anatomy of the musculocutaneous latissimus dorsi flap for neophalloplasty.

PubMed

Dennis, M; Granger, A; Ortiz, A; Terrell, M; Loukos, M; Schober, J

2018-03-01

In transgender surgery, the ideal neophallus is one that: (a) is constructed using a reproducible procedure, (b) possesses tactile and erogenous sensation, (c) is large and rigid enough (naturally, or using a prosthesis) to permit penetrative intercourse, (d) leaves acceptable donor site morbidity, (e) results in esthetically satisfactory appearance, and (f) allows for voiding while standing. The musculocutaneous latissimus dorsi (MLD) flap has favorable results in the area of neophalloplasty. Among its advantages are acceptable donor site appearance, stiffness sufficient for intercourse, and esthetically satisfactory genital appearance. The anatomy of the MLD flap supports the creation of a neophallus for transsexual anatomy revision. Herein, we give an overview of the advantages and disadvantages of the procedure, and the anatomical details and surgical steps involved. Novel illustrations were created from standard surgical text descriptions to clarify this topic for surgical training and patient understanding and decision making. A review of the relevant literature regarding the anatomy, procedure development, and outcomes is presented. The MLD flap uses part of the latissimus dorsi muscle with branches of the thoracodorsal vessels and nerve to construct a neophallus. A thin strip of muscle around the pedicle is harvested, resulting in a slightly curvilinear scar. The blood supply is connected to the femoral artery and saphenous vein or the deep inferior epigastric artery and vein, while the nerve is connected to the ilioinguinal nerve or the obturator nerve. The MLD flap for neophalloplasty is a reliable graft with a well concealed scar and low donor site morbidity. Clin. Anat. 31:152-159, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Desirable Difficulties in Vocabulary Learning

PubMed Central

BJORK, ROBERT A.; KROLL, JUDITH F.

2016-01-01

In this article we discuss the role of desirable difficulties in vocabulary learning from two perspectives, one having to do with identifying conditions of learning that impose initial challenges to the learner but then benefit later retention and transfer, and the other having to do with the role of certain difficulties that are intrinsic to language processes, are engaged during word learning, and reflect how language is understood and produced. From each perspective we discuss evidence that supports the notion that difficulties in learning and imposed costs to language processing may produce benefits because they are likely to increase conceptual understanding. We then consider the consequences of these processes for actual second-language learning and suggest that some of the domain-general cognitive advantages that have been reported for proficient bilinguals may reflect difficulties imposed by the learning process, and by the requirement to negotiate cross-language competition, that are broadly desirable. As Alice Healy and her collaborators were perhaps the first to demonstrate, research on desirable difficulties in vocabulary and language learning holds the promise of bringing together research traditions on memory and language that have much to offer each other. PMID:26255443

Desirable Difficulties in Vocabulary Learning.

PubMed

Bjork, Robert A; Kroll, Judith F

2015-01-01

In this article we discuss the role of desirable difficulties in vocabulary learning from two perspectives, one having to do with identifying conditions of learning that impose initial challenges to the learner but then benefit later retention and transfer, and the other having to do with the role of certain difficulties that are intrinsic to language processes, are engaged during word learning, and reflect how language is understood and produced. From each perspective we discuss evidence that supports the notion that difficulties in learning and imposed costs to language processing may produce benefits because they are likely to increase conceptual understanding. We then consider the consequences of these processes for actual second-language learning and suggest that some of the domain-general cognitive advantages that have been reported for proficient bilinguals may reflect difficulties imposed by the learning process, and by the requirement to negotiate cross-language competition, that are broadly desirable. As Alice Healy and her collaborators were perhaps the first to demonstrate, research on desirable difficulties in vocabulary and language learning holds the promise of bringing together research traditions on memory and language that have much to offer each other.

A multiplex PCR method discriminating between the TYLCV and TYLCV-Mld clades of tomato yellow leaf curl virus.

PubMed

Lefeuvre, P; Hoareau, M; Delatte, H; Reynaud, B; Lett, J-M

2007-09-01

Tomato yellow leaf curl virus (TYLCV) is one of the causal agents of tomato yellow leaf curl disease (TYLCD) and can cause up to 100% yield losses in tomato fields. As TYLCV continues to spread, many isolates have been described in different parts of the world. Recently two closely related but distinct TYLCV clades, called TYLCV and TYLCV-Mld, have been identified. Isolates from those two clades differ mainly in the nucleotide sequences of their replication associated protein genes but do not display significantly different symptomatology. In order to improve monitoring of the rapidly expanding worldwide TYLCD epidemic, a multiplex polymerase chain reaction assay (mPCR) was developed. A set of three primers were designed to detect and characterize the TYLCV and TYLCV-Mld clade isolates. The specificity and sensitivity of the mPCR were validated on TYLCV infected tomato plants and Bemisia tabaci whiteflies. Being cheap, fast and highly sensitive this new diagnostic tool should greatly simplify efforts to trace the global spread of TYLCV.

Molecular layer deposition of alucone films using trimethylaluminum and hydroquinone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choudhury, Devika; Sarkar, Shaibal K., E-mail: shaibal.sarkar@iitb.ac.in; Mahuli, Neha

2015-01-01

A hybrid organic–inorganic polymer film grown by molecular layer deposition (MLD) is demonstrated here. Sequential exposures of trimethylaluminum [Al(CH{sub 3}){sub 3}] and hydroquinone [C{sub 6}H{sub 4}(OH){sub 2}] are used to deposit the polymeric films, which is a representative of a class of aluminum oxide polymers known as “alucones.” In-situ quartz crystal microbalance (QCM) studies are employed to determine the growth characteristics. An average growth rate of 4.1 Å per cycle at 150 °C is obtained by QCM and subsequently verified with x-ray reflectivity measurements. Surface chemistry during each MLD-half cycle is studied in depth by in-situ Fourier transform infrared (FTIR) vibrationmore » spectroscopy. Self limiting nature of the reaction is confirmed from both QCM and FTIR measurements. The conformal nature of the deposit, typical for atomic layer deposition and MLD, is verified with transmission electron microscopy imaging. Secondary ion mass spectroscopy measurements confirm the uniform elemental distribution along the depth of the films.« less

On the response of subduction in the South Pacific to an intensification of westerlies and heat flux in an eddy permitting ocean model

NASA Astrophysics Data System (ADS)

Liu, Chengyan; Wang, Zhaomin; Li, Bingrui; Cheng, Chen; Xia, Ruibin

2017-04-01

Based on an eddy permitting ocean general circulation model, the response of water masses to two distinct climate scenarios in the South Pacific is assessed in this paper. Under annually repeating atmospheric forcing that is characterized by different westerlies and associated heat flux, the response of Subantarctic Mode Water (SAMW) and Antarctic Intermediate Water (AAIW) is quantitatively estimated. Both SAMW and AAIW are found to be warmer, saltier and denser under intensified westerlies and increased heat loss. The increase in the subduction volume of SAMW and AAIW is about 19.8 Sv (1 Sv = 106 m3 s-1). The lateral induction term plays a dominant role in the changes in the subduction volume due to the deepening of the mixed layer depth (MLD). Furthermore, analysis of the buoyancy budget is used to quantitatively diagnose the reason for the changes in the MLD. The deepening of the MLD is found to be primarily caused by the strengthening of heat loss from the ocean to the atmosphere in the formation region of SAMW and AAIW.

[The comorbidity of learning difficulties and ADHD symptoms in primary-school-age children].

PubMed

Schuchardt, Kirsten; Fischbach, Anne; Balke-Melcher, Christina; Mähler, Claudia

2015-05-01

Children having difficulties in acquiring early literacy and mathematical skills often show an increased rate of inattention, hyperactivity, and impulsivity. This study provides data on the comorbidity rates of specific learning difficulties and ADHD symptoms. We analyzed the data of 273 children with learning difficulties despite an at least average IQ, 57 children with low IQ, and 270 children without learning difficulties and average IQ (comparison group). We assessed children’s IQ and school achievement using standardized achievement tests. ADHD symptoms were assessed via parents’ ratings. Our results showed that only 5 % of both the control group and the group with solely mathematical difficulties fulfilled the criteria of an ADHD subtype according to the DSM-IV based on parents’ ratings. In contrast, this was the case in even 20 % of the children with difficulties in reading/writing and of those with low IQ. Compared to girls, boys in the control group had a 150% higher risk for matching the criteria of one of the ADHD subtypes in parents’ ratings, whereas boys with learning difficulties and those with low IQ had an even 200% to 600% higher risk for it. The relationship between learning difficulties and ADHD symptoms can be found predominantly in the inattentive type. Possible reasons for the results are discussed.

Learning difficulties of senior high school students based on probability understanding levels

NASA Astrophysics Data System (ADS)

Anggara, B.; Priatna, N.; Juandi, D.

2018-05-01

Identifying students' difficulties in learning concept of probability is important for teachers to prepare the appropriate learning processes and can overcome obstacles that may arise in the next learning processes. This study revealed the level of students' understanding of the concept of probability and identified their difficulties as a part of the epistemological obstacles identification of the concept of probability. This study employed a qualitative approach that tends to be the character of descriptive research involving 55 students of class XII. In this case, the writer used the diagnostic test of probability concept learning difficulty, observation, and interview as the techniques to collect the data needed. The data was used to determine levels of understanding and the learning difficulties experienced by the students. From the result of students' test result and learning observation, it was found that the mean cognitive level was at level 2. The findings indicated that students had appropriate quantitative information of probability concept but it might be incomplete or incorrectly used. The difficulties found are the ones in arranging sample space, events, and mathematical models related to probability problems. Besides, students had difficulties in understanding the principles of events and prerequisite concept.

Social competence and learning difficulties: Teacher perceptions.

PubMed

Wight, Megan; Chapparo, Christine

2008-12-01

Social competence has been linked to children's classroom performance with three out of four children with learning difficulties reported to have problems with social skills. Social participation remains a predominant childhood occupation and a key indicator of school performance. Occupational therapists work with teachers to accurately assess the social performance of children in context and to provide targeted intervention. There is limited research about what teachers perceive are the specific nature of social difficulties experienced by children with learning difficulties in the classroom. This study investigated teacher perceptions of the social competence of a small sample of Australian boys with learning difficulties within the classroom context. The Teacher Skillstreaming Checklist was used to investigate teacher perceptions of the social abilities of 21 primary school aged boys with learning difficulties compared to a control group. A correlational analysis was used to examine the relationship. The study identified that the boys with learning difficulties were perceived by their teachers as having poorer social performance across multiple domains when compared to their typically developing peers. Implications of these findings are that children's social performance may negatively impact learning and classroom participation and that for some children, social competence should be a focus of occupational therapy assessment and treatment.

Magneto-Optic Materials for Biasing Ring Laser Gyros. Report Number 3. (Computer Model for Evaluating Scattering from Multi-Layer Dielectric Thin Film Structures Containing a Magnetic Layer.

DTIC Science & Technology

1980-09-30

16. "Substituted Rare Earth Garnet Substrate Crystals and LPE Films for Magneto-optic Applications," M. Kestigian, W.R. Bekebrede and A.B. Smith, J...transparent garnet magnetic films have been discussed by workers at Sperry [4,5]. The above considerations indicate that it is highly desirable to have...metallic magnetic film , such as a garnet , on top of an MLD stack. C. A partially transparent (very thin) magnetic metal film on top of an MLD stack. We

[Metachromatic Leukodystrophy. Case Presentation].

PubMed

Espejo, Lina María; de la Espriella, Ricardo; Hernández, José Fernando

Metachromatic leukodystrophy (MLD) is a rare demyelinating disease (prevalence 1:40 000), also called arylsulfatase A deficiency (ARS-A), which may present with neurological and psychiatric symptoms. Clinical assessment may be difficult, due to unspecific signs and symptoms. A case is presented of a 16 year-old female patient seen in psychiatry due to behavioural changes, psychosis, and with impaired overall performance. She was initially diagnosed with schizophrenia, but the Nuclear Magnetic Resonance (NMR) scan and laboratory tests lead to the diagnosis of MLD. Copyright © 2016 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

A Case Study on Learning Difficulties and Corresponding Supports for Learning in cMOOCs

ERIC Educational Resources Information Center

Li, Shuang; Tang, Qi; Zhang, Yanxia

2016-01-01

cMOOCs, which are based on connectivist learning theory, bring challenges for learners as well as opportunities for self-inquiry. Previous studies have shown that learners in cMOOCs may have difficulties learning, but these studies do not provide any in-depth, empirical explorations of student difficulties or support strategies. This paper…

Medical students’ perceptions and understanding of their specific learning difficulties

PubMed Central

Abbott, Stephen; Bevere, Grazia; Roberts, Christopher M.

2013-01-01

Objectives The purpose of this study is to explore how medical students with Specific Learning Difficulties perceive and understand their Specific Learning Difficulty and how it has impacted on their experience of medical training. Method A purposive sample of fifteen students from one medical school was interviewed. Framework Analysis was used to identify and organise themes emerging from the data. An interpretation of the data was made capturing the essence of what had been learned. The concept of ‘reframing’ was then used to re-analyse and organise the data. Results Students reported having found ways to cope with their Specific Leaning Difficulty in the past, some of which proved inadequate to deal with the pressures of medical school. Diagnosis was a mixed experience: many felt relieved to understand their difficulties better, but some feared discrimination. Practical support was available in university but not in placement. Students focused on the impact of their Specific Learning Difficulty on their ability to pass undergraduate exams. Most did not contemplate difficulties post-qualification. Conclusions The rigours of the undergraduate medical course may reveal undisclosed Specific Learning Difficulties. Students need help to cope with such challenges, psychologically and practically in both classroom and clinical practice. University services for students with Specific Learning Difficulties should become familiar with the challenges of clinical placements, and ensure that academic staff has access to information about the needs of these students and how these can be met.

Pharmacokinetics and brain uptake in the rhesus monkey of a fusion protein of arylsulfatase a and a monoclonal antibody against the human insulin receptor.

PubMed

Boado, Ruben J; Lu, Jeff Zhiqiang; Hui, Eric K-W; Sumbria, Rachita K; Pardridge, William M

2013-05-01

Metachromatic leukodystrophy (MLD) is a lysosomal storage disorder of the brain caused by mutations in the gene encoding the lysosomal sulfatase, arylsulfatase A (ASA). It is not possible to treat the brain in MLD with recombinant ASA, because the enzyme does not cross the blood-brain barrier (BBB). In the present investigation, a BBB-penetrating IgG-ASA fusion protein is engineered and expressed, where the ASA monomer is fused to the carboxyl terminus of each heavy chain of an engineered monoclonal antibody (MAb) against the human insulin receptor (HIR). The HIRMAb crosses the BBB via receptor-mediated transport on the endogenous BBB insulin receptor, and acts as a molecular Trojan horse to ferry the ASA into brain from blood. The HIRMAb-ASA is expressed in stably transfected Chinese hamster ovary cells grown in serum free medium, and purified by protein A affinity chromatography. The fusion protein retains high affinity binding to the HIR, EC50 = 0.34 ± 0.11 nM, and retains high ASA enzyme activity, 20 ± 1 units/mg. The HIRMAb-ASA fusion protein is endocytosed and triaged to the lysosomal compartment in MLD fibroblasts. The fusion protein was radio-labeled with the Bolton-Hunter reagent, and the [(125) I]-HIRMAb-ASA rapidly penetrates the brain in the Rhesus monkey following intravenous administration. Film and emulsion autoradiography of primate brain shows global distribution of the fusion protein throughout the monkey brain. These studies describe a new biological entity that is designed to treat the brain of humans with MLD following non-invasive, intravenous infusion of an IgG-ASA fusion protein. Copyright © 2012 Wiley Periodicals, Inc.

Lithospheric Layering beneath Southern Africa Constrained by S-to-P Receiver Functions

NASA Astrophysics Data System (ADS)

Liu, L.; Liu, K. H.; Gao, S. S.

2016-12-01

To investigate the existence of intra-lithospheric interfaces in an area of active rifting of ancient lithosphere, we stack S-to-P receiver functions (SRFs) recorded by broadband seismic stations in the vicinity of the non-volcanic sections of the East African Rift System and the stable Kaapvaal and Zimbabwe cratons. The data set was recorded by about 200 permanent and portable seismic stations installed over the past 30 years. The SRFs are computed using frequency-domain deconvolution, and are stacked in consecutive circles with a radius of 2 degrees. They are converted to depth series after moveout corrections using the IASP91 Earth model. In the upper mantle , a robust negative arrival is found in virtually all the stacked traces in the depth range of 50-100 km. Comparison with results from seismic tomography and mantle xenolith studies suggests that this discontinuity represents a mid-lithospheric discontinuity (MLD), similar to what was observed beneath the North American continent. The absence of observable negative arrivals in the anticipated depth of 250 km or greater beneath the study area suggests a gradual instead of sharp transition from the lithosphere to the asthenosphere. No significant shallowing of the MLD is observed beneath the young rift segments, suggesting that rifting is limited in the crust, an observation that is consistent with recent results from the SAFARI (Seismic Arrays for African Rift Initiation) project. The shallowest MLD of about 65 km in the study area is found in a NW-SE trending zone across central Zimbabwe and western Zambia. The MLD may reflect a low velocity zone caused by metasomatism, a process commonly found beneath ancient cratons.

Phthalates in Commercial Chinese Rice Wines: Concentrations and the Cumulative Risk Assessment to Adult Males in Shanghai.

PubMed

Huang, Yue; Lu, Wen Wei; Chen, Bo; You, Jie; Wu, Min; Li, Shu Guang

2014-10-01

The concentrations of 16 phthalates in 164 commercial Chinese rice wines (CRW) were detected by GC-MS, and consumption data on CRW in different packaging types was investigated from 634 adult males in Shanghai using a food frequency questionnaire. Based on the principles of probabilistic modelling and cumulative risk assessment, the exposure and health risk of phthalates from CRW to adult males in Shanghai was evaluated. DMP, DEP, DIBP, DnBP, BBP, and DEHP were detected in the samples, the range of detection frequency of individual phthalates varied from 6.10% for BBP to 15.24% for DIBP, and the detected concentrations were 51.06-200.34 ng/mL. All the respondents consumed CRW, 90.69% of them consumed CRW 0.01-49.9 mL/d, the minimum value of the average daily intake of CRW was 6.25 mL/d, the median was 13.72 mL/d and the maximum was 300 mL/d. The median exposure level of the 6 detected Phthalates to adult males in Shanghai were 6.58-7.10 ng/(d•kg), and the maximum exposure level were 137.38-540.47 ng/(d•kg). The cumulative exposure health risk index (HI) based on the median and maximum exposure level of the 6 Phthalates (DMP, DEP, DIBP, DnBP, BBP, and DEHP) were 0.001147 and 0.063396, both were far less than 1. In conclusion, CRW were generally consumed by the adult males in Shanghai, although multiple phthalates were detected in commercial CRW, health risk of such exposure levels from commercial CRW to the target adult males in Shanghai was very low. Copyright © 2014 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

Can we map the interannual variability of the whole upper Southern Ocean with the current database of hydrographic observations?

NASA Astrophysics Data System (ADS)

Heuzé, Céline; Vivier, Frédéric; Le Sommer, Julien; Molines, Jean-Marc; Penduff, Thierry

2016-04-01

With the advent of Argo floats, it now seems feasible to study the interannual variations of upper ocean hydrographic properties of the historically undersampled Southern Ocean. To do so, scattered hydrographic profiles often first need to be mapped. To investigate biases and errors associated both with the limited space-time distribution of the profiles and with the mapping methods, we colocate the mixed layer depth (MLD) output from a state-of-the-art 1/12° DRAKKAR simulation onto the latitude, longitude and date of actual in-situ profiles from 2005 to 2014. We compare the results obtained after remapping using a nearest-neighbor (NN) interpolation and an objective analysis (OA) with different spatio-temporal grid resolutions and decorrelation scales. NN is improved with a coarser resolution. OA performs best with low decorrelation scales, avoiding too strong a smoothing, but returns values over larger areas with large decorrelation scales and low temporal resolution, as more points are available. For all resolutions OA represents better the annual extreme values than NN. Both methods underestimate the seasonal cycle in MLD. MLD biases are lower than 10 m on average but can exceed 250 m locally in winter. We argue that current Argo data should not be mapped to infer decadal trends in MLD, as all methods are unable to reproduce existing trends without creating unrealistic extra ones. We also show that regions of the subtropical Atlantic, Indian and Pacific Oceans, and the whole ice-covered Southern Ocean, still cannot be mapped even by the best method because of the lack of observational data. This article is protected by copyright. All rights reserved.

Improved correlation between CT emphysema quantification and pulmonary function test by density correction of volumetric CT data based on air and aortic density.

PubMed

Kim, Song Soo; Seo, Joon Beom; Kim, Namkug; Chae, Eun Jin; Lee, Young Kyung; Oh, Yeon Mok; Lee, Sang Do

2014-01-01

To determine the improvement of emphysema quantification with density correction and to determine the optimal site to use for air density correction on volumetric computed tomography (CT). Seventy-eight CT scans of COPD patients (GOLD II-IV, smoking history 39.2±25.3 pack-years) were obtained from several single-vendor 16-MDCT scanners. After density measurement of aorta, tracheal- and external air, volumetric CT density correction was conducted (two reference values: air, -1,000 HU/blood, +50 HU). Using in-house software, emphysema index (EI) and mean lung density (MLD) were calculated. Differences in air densities, MLD and EI prior to and after density correction were evaluated (paired t-test). Correlation between those parameters and FEV1 and FEV1/FVC were compared (age- and sex adjusted partial correlation analysis). Measured densities (HU) of tracheal- and external air differed significantly (-990 ± 14, -1016 ± 9, P<0.001). MLD and EI on original CT data, after density correction using tracheal- and external air also differed significantly (MLD: -874.9 ± 27.6 vs. -882.3 ± 24.9 vs. -860.5 ± 26.6; EI: 16.8 ± 13.4 vs. 21.1 ± 14.5 vs. 9.7 ± 10.5, respectively, P<0.001). The correlation coefficients between CT quantification indices and FEV1, and FEV1/FVC increased after density correction. The tracheal air correction showed better results than the external air correction. Density correction of volumetric CT data can improve correlations of emphysema quantification and PFT. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Importance of solar subsurface heating in ocean general circulation models

NASA Astrophysics Data System (ADS)

Rochford, Peter A.; Kara, A. Birol; Wallcraft, Alan J.; Arnone, Robert A.

2001-12-01

The importance of subsurface heating on surface mixed layer properties in an ocean general circulation model (OGCM) is examined using attenuation of solar irradiance with depth below the ocean surface. The depth-dependent attenuation of subsurface heating is given by global monthly mean fields for the attenuation of photosynthetically available radiation (PAR), kPAR. These global fields of kPAR are derived from Sea-viewing Wide Field-of-view Sensor (SeaWiFS) data on the spectral diffuse attenuation coefficient at 490 nm (k490), and have been processed to have the smoothly varying and continuous coverage necessary for use in OGCM applications. These monthly fields provide the first complete global data sets of subsurface optical fields that can be used for OGCM applications of subsurface heating and bio-optical processes. The effect on global OGCM prediction of sea surface temperature (SST) and surface mixed layer depth (MLD) is examined when solar heating, as given by monthly mean kPAR and PAR fields, is included in the model. It is found that subsurface heating yields a marked increase in the SST predictive skill of the OGCM at low latitudes. No significant improvement in MLD predictive skill is obtained when including subsurface heating. Use of the monthly mean kPAR produces an SST decrease of up to 0.8°C and a MLD increase of up to only 4-5 m for climatological surface forcing, with this primarily confined to the equatorial regions. Remarkably, a constant kPAR value of 0.06 m-1, which is indicative of optically clear open ocean conditions, is found to serve very well for OGCM prediction of SST and MLD over most of the global ocean.

Difficulties of Diabetic Patients in Learning about Their Illness.

ERIC Educational Resources Information Center

Bonnet, Caroline; Gagnayre, Remi; d'Ivernois, Jean Francois

2001-01-01

Examines the difficulties experienced by diabetic patients in learning about their illness. Diabetic people (N=138) were questioned by means of a closed answer questionnaire. Results reveal that patients easily acquired manual skills, yet numerous learning difficulties were associated with the skills required to solve problems and make decisions,…

Learning Difficulty and Learner Identity: A Symbiotic Relationship

ERIC Educational Resources Information Center

Hirano, Eliana

2009-01-01

This paper reports on a longitudinal case study of an adult EFL learner who perceived himself as having difficulty learning English. Both learning difficulty and learner identity are viewed as being constructed in discursive interactions throughout one's life and, hence, amenable to reconstruction. Data collected from classroom interactions,…

The System of the Learner Experiencing Difficulty: Some Reflections on the Use of a Simulation as a Tool for Investigating and Analysing Elements of a Complex System.

ERIC Educational Resources Information Center

Thatcher, Donald; Robinson, June

1990-01-01

Discusses learning systems and learning difficulties, and describes the use of a simulation to help professionals better understand people with learning difficulties. The General Systems Theory and a systems approach are discussed, the role of debriefing is considered, and theoretical perspectives on the development of learning disabilities are…

Using Biology Education Research and Qualitative Inquiry to Inform Genomic Nursing Education.

PubMed

Ward, Linda D

Decades of research in biology education show that learning genetics is difficult and reveals specific sources of learning difficulty. Little is known about how nursing students learn in this domain, although they likely encounter similar difficulties as nonnursing students. Using qualitative approaches, this study investigated challenges to learning genetics among nursing students. Findings indicate that nursing students face learning difficulties already identified among biology students, suggesting that nurse educators might benefit from biology education research.

Analysis of difficulties in mathematics learning on students with guardian personality type in problem-solving HOTS geometry test

NASA Astrophysics Data System (ADS)

Karimah, R. K. N.; Kusmayadi, T. A.; Pramudya, I.

2018-04-01

Learning in the current 2013 curriculum is based on contextual issues based on questions that can encourage students to think broadly. HOTS is a real-life based assessment of everyday life, but in practice, the students are having trouble completing the HOTS issue. Learning difficulty is also influenced by personality type Based on the fact that the real difference one can see from a person is behavior. Kersey classifies the personality into 4 types, namely Idealist, Rational, Artisan, and Guardian. The researcher focuses on the type of guardian personality that is the type of personality that does not like the picture. This study aims to describe the difficulty of learning mathematics in students with a type of guardian personality in the completion of Geometry materials especially in solving HOTS. This research type is descriptive qualitative research. Instruments used in this study were the researchers themselves, personality class test sheets, learning difficulty test sheets in the form of HOTS Geometry test, and interview guides. The results showed that students with guardian personality it was found that a total of 3.37 % difficulties of number fact skill, 4.49 % difficulties of arithmetics skill, 37.08 % difficulties of information skill, 31.46% difficulties of language skill, 23.60 % difficulties of visual-spatial skill.

Psychometric Properties of a Newly Developed Learning Difficulties Scale in the Omani Society

ERIC Educational Resources Information Center

Al-Qaryout, Ibrahim A.; Abu-Hilal, Maher M.; Alsulaimani, Humaira

2013-01-01

Introduction: Learning difficulties (LD) is a recent construct. It has been agreed that the individual who suffers from learning difficulties has a disorder in one or more of the basis psychological processes, including attention, cognition, formation of concepts, memory, problem solving, understanding or reading, speaking or writing, or…

Reconsidering Learning Difficulties and Misconceptions in Chemistry: Emergence in Chemistry and Its Implications for Chemical Education

ERIC Educational Resources Information Center

Tümay, Halil

2016-01-01

Identifying students' misconceptions and learning difficulties and finding effective ways of addressing them has been one of the major concerns in chemistry education. However, the chemistry education community has paid little attention to determining discipline-specific aspects of chemistry that can lead to learning difficulties and…

Men with Learning Difficulties Doing Research: Challenging Views of Learning Difficulties

ERIC Educational Resources Information Center

Inglis, Pamela A.; Swain, John

2012-01-01

This paper explores the views of men with learning difficulties living in a secure environment. Reflecting findings from a doctoral thesis based upon a research project where the participants looked at the processes and concepts of research, the dialogues within the study were analysed using critical discourse analysis. Thesis aims relevant here…

Researching Learning Difficulties: A Guide for Practitioners

ERIC Educational Resources Information Center

Porter, Jill; Lacey, Penny

2005-01-01

The aim of this book is to provide a source for teachers and other professionals working with children and adults with learning difficulties and disabilities that will enable them to: (1) access selected recent and relevant research in the field of learning difficulties, drawn from a range of disciplines and groups of people; (2) reflect on…

Laptops Meet Schools, One-One Draw: M-Learning for Secondary Students with Literacy Difficulties

ERIC Educational Resources Information Center

Conway, Paul F.; Amberson, Jessica

2011-01-01

Mobile technology-enhanced literacy initiatives have become a focus of efforts to support learning for students with literacy difficulties. The "Laptops Initiative for Post-Primary Students with Dyslexia or other Reading/Writing Difficulties" offers insights into and addresses questions about ICT policy making regarding m-learning technologies for…

Learning Difficulties: A Portuguese Perspective of a Universal Issue

ERIC Educational Resources Information Center

Martins, Ana Paula Loucao; Correia, Luis de Miranda; Hallahan, Daniel P.

2012-01-01

In this article we present findings of a study that was conducted with the purpose of deepening the knowledge about the field of learning difficulties in Portugal. Therefore, within these findings we will discuss across several cultural boundaries, themes related with the existence of learning difficulties as a construct, the terminology, the…

Effects of manual lymph drainage on cardiac autonomic tone in healthy subjects.

PubMed

Kim, Sung-Joong; Kwon, Oh-Yun; Yi, Chung-Hwi

2009-01-01

This study was designed to investigate the effects of manual lymph drainage on the cardiac autonomic tone. Thirty-two healthy male subjects were randomly assigned to manual lymph drainage (MLD) (experimental) and rest (control) groups. Electrocardiogram (ECG) parameters were recorded with bipolar electrocardiography using standard limb lead positions. The pressure-pain threshold (PPT) was quantitatively measured using an algometer. Heart rate variability differed significantly between the experimental and control groups (p < 0.05), but the PPT in the upper trapezius muscle did not (p > 0.05). These findings indicate that the application of MLD was effective in reducing the activity of the sympathetic nervous system.

Cichoric acid improved hyperglycaemia and restored muscle injury via activating antioxidant response in MLD-STZ-induced diabetic mice.

PubMed

Zhu, Di; Zhang, Xinglin; Niu, Yajie; Diao, Zhijun; Ren, Bo; Li, Xingyu; Liu, Zhigang; Liu, Xuebo

2017-09-01

Cichoric acid (CA), extracted from edible plants and vegetables, is a potential natural nutraceutical, with antioxidant and hypoglycaemic biological functions. The objective of this study was to explore the potential underlying molecular mechanisms involved in normalizing diabetes-related changes in hyperglycaemia via pancreas apoptosis and muscle injury induced by multiple low-dose STZ (MLD-STZ) injection in response to dietary supplementation with CA. To induce the MLD-STZ diabetic mice, the C57BL/6J mice were intraperitoneally injected with STZ (50 mg/kg body weight) for consecutive five days. CA (60 mg/kg/d) was supplemented in drinking water for 4 weeks. Compared with control, CA inhibited pancreas apoptosis and adjusted islet function in diabetic mice, leading to an increase in insulin generation and secretion. Moreover, CA regulated mitochondrial biogenesis, glycogen synthesis, and inhibited inflammation via activating antioxidant responses, which contributes to the improvement in athletic ability and diabetic myopathy. In general, CA is a natural food-derived compound with the potential application for regulating glucose homeostasis and improving diabetes and its complications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gene therapy for metachromatic leukodystrophy.

PubMed

Rosenberg, Jonathan B; Kaminsky, Stephen M; Aubourg, Patrick; Crystal, Ronald G; Sondhi, Dolan

2016-11-01

Leukodystrophies (LDs) are rare, often devastating genetic disorders with neurologic symptoms. There are currently no disease-specific therapeutic approaches for these diseases. In this review we use metachromatic leukodystrophy as an example to outline in the brief the therapeutic approaches to MLD that have been tested in animal models and in clinical trials, such as enzyme-replacement therapy, bone marrow/umbilical cord blood transplants, ex vivo transplantation of genetically modified hematopoietic stem cells, and gene therapy. These studies suggest that to be successful the ideal therapy for MLD must provide persistent and high level expression of the deficient gene, arylsulfatase A in the CNS. Gene therapy using adeno-associated viruses is therefore the ideal choice for clinical development as it provides the best balance of potential for efficacy with reduced safety risk. Here we have summarized the published preclinical data from our group and from others that support the use of a gene therapy with AAVrh.10 serotype for clinical development as a treatment for MLD, and as an example of the potential of gene therapy for LDs especially for Krabbe disease, which is the focus of this special issue. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kreysing, J.; Bohne, W.; Boesenberg, C.

The authors identified a patient suffering from late-infantile metachromatic leukodystrophy (MLD) who has a residual arylsulfatase A (ARSA) activity of about 10%. Fibroblasts of the patient show significant sulfatide degradation activity exceeding that of adult MLD patients. Analysis of the ARSA gene in this patient revealed heterozygosity for two new mutant alleles: in one allele, deletion of C 447 in exon 2 leads to a frameshift and to a premature stop codon at amino acid position 105; in the second allele, a G[yields]A transition in exon 5 causes a Gly[sup 309][yields]Ser substitution. Transient expression of the mutant Ser[sup 309]-ARSA resultedmore » in only 13% enzyme activity of that observed in cells expressing normal ARSA. The mutant ARSA is correctly targeted to the lyosomes but is unstable. These findings are in contrast to previous results showing that the late-infantile type of MLD is always associated with the complete absence of ARSA activity. The expression of the mutant ARSA protein may be influenced by particular features of oligodendrocytes, such that the level of mutant enzymes is lower in these cells than in others. 23 refs., 4 figs., 2 tabs.« less

Why do organizations not learn from incidents? Bottlenecks, causes and conditions for a failure to effectively learn.

PubMed

Drupsteen, Linda; Hasle, Peter

2014-11-01

If organizations would be able to learn more effectively from incidents that occurred in the past, future incidents and consequential injury or damage can be prevented. To improve learning from incidents, this study aimed to identify limiting factors, i.e. the causes of the failure to effectively learn. In seven organizations focus groups were held to discuss factors that according to employees contributed to the failure to learn. By use of a model of the learning from incidents process, the steps, where difficulties for learning arose, became visible, and the causes for these difficulties could be studied. Difficulties were identified in multiple steps of the learning process, but most difficulties became visible when planning actions, which is the phase that bridges the gap from incident investigation to actions for improvement. The main causes for learning difficulties, which were identified by the participants in this study, were tightly related to the learning process, but some indirect causes - or conditions - such as lack of ownership and limitations in expertise were also mentioned. The results illustrate that there are two types of causes for the failure to effectively learn: direct causes and indirect causes, here called conditions. By actively and systematically studying learning, more conditions might be identified and indicators for a successful learning process may be determined. Studying the learning process does, however, require a shift from learning from incidents to learning to learn. Copyright © 2014 Elsevier Ltd. All rights reserved.

Upper Water Structure and Mixed Layer Depth in Sub-Tropical Waters: The Seats Station in the Northern South China Sea

NASA Astrophysics Data System (ADS)

Wong, G. T. F.; Tai, J. H.

2014-12-01

702 CTD profiles were collected in the subtropical northern South China Sea at and in the vicinity of the SouthEast Asian Time-series Study (SEATS) station (18.2oN, 115.8oE) between 17.5 and 18.5oN and 115.3 and 116.3oE in 64 cruises in 1997 to 2013. The hydrographic structure of the upper water above the permanent thermocline may be classified into 4 principal types: (a) classic type (an almost isopycnic upper water); (b) stepwise type (with one or more small but significant step-increases in σθ in the upper water); (c) graded type (an approximately constant depth gradient in a monotonic increase in σθ in the upper water); and (d) mixed type (a combination of the stepwise and graded types). The 4 types of upper water were found in 75, 14, 5, and 6% of the cruises, respectively. Ten schemes were applied to these data to determine the mixed layer depth (MLD): 4 fixed temperature difference (FTD) methods (0.2, 0.5, 0.8 and 1.0oC decrease from 10 m); 1 fixed density difference (FDD) method (0.125 σθ increase from 10 m); 1 fixed temperature gradient (FTG) method (at 0.05oC/m); 3 fixed density gradient (FDG) methods (at 0.01, 0.05 and 0.1 σθ/m); and the maximum density gradient (MDG) method. MLD could not be clearly depicted in the 3 minor types of upper water. In the classical type, while similar MLD-s were found in a large majority of the cruises among all 10 methods, substantial discrepancies among methods could be found. The most consistent results, generally within ±5 m, were found among the FDG method at 0.05, 0.1 σθ/m and FTD method at 0.8 and 1.0oC. The MDG method gave consistently deeper MLD by ~8 m. If that difference was taken into account, the results were generally consistent with those from the other 4 methods. The remaining 5 methods could all yield MLD-s shallower than the first 4 methods by >10 m as they failed to capture the bottom of the mixed layer as indicated by visual inspection.

Growth, characterization and post-processing of inorganic and hybrid organic-inorganic thin films deposited using atomic and molecular layer deposition techniques

NASA Astrophysics Data System (ADS)

Abdulagatov, Aziz Ilmutdinovich

Atomic layer deposition (ALD) and molecular layer deposition (MLD) are advanced thin film coating techniques developed for deposition of inorganic and hybrid organic-inorganic films respectively. Decreasing device dimensions and increasing aspect ratios in semiconductor processing has motivated developments in ALD. The beginning of this thesis will cover study of new ALD chemistry for high dielectric constant Y 2O3. In addition, the feasibility of conducting low temperature ALD of TiN and TiAlN is explored using highly reactive hydrazine as a new nitrogen source. Developments of these ALD processes are important for the electronics industry. As the search for new materials with more advanced properties continues, attention has shifted toward exploring the synthesis of hierarchically nanostructured thin films. Such complex architectures can provide novel functions important to the development of state of the art devices for the electronics industry, catalysis, energy conversion and memory storage as a few examples. Therefore, the main focus of this thesis is on the growth, characterization, and post-processing of ALD and MLD films for fabrication of novel composite (nanostructured) thin films. Novel composite materials are created by annealing amorphous ALD oxide alloys in air and by heat treatment of hybrid organic-inorganic MLD films in inert atmosphere (pyrolysis). The synthesis of porous TiO2 or Al2O3 supported V2O5 for enhanced surface area catalysis was achieved by the annealing of inorganic TiVxOy and AlV xOy ALD films in air. The interplay between phase separation, surface energy difference, crystallization, and melting temperature of individual oxides were studied for their control of film morphology. In other work, a class of novel metal oxide-graphitic carbon composite thin films was produced by pyrolysis of MLD hybrid organic-inorganic films. For example, annealing in argon of titania based hybrid films enabled fabrication of thin films of intimately mixed TiO2 and nanographitized carbon. The graphitized carbon in the film was formed as a result of the removal of hydrogen by pyrolysis of the organic constituency of the MLD film. The presence of graphitic carbon allowed a 14 orders of magnitude increase in the electrical conductivity of the composite material compared fully oxidized rutile TiO 2.

Errors in Multi-Digit Arithmetic and Behavioral Inattention in Children With Math Difficulties

PubMed Central

Raghubar, Kimberly; Cirino, Paul; Barnes, Marcia; Ewing-Cobbs, Linda; Fletcher, Jack; Fuchs, Lynn

2009-01-01

Errors in written multi-digit computation were investigated in children with math difficulties. Third-and fourth-grade children (n = 291) with coexisting math and reading difficulties, math difficulties, reading difficulties, or no learning difficulties were compared. A second analysis compared those with severe math learning difficulties, low average achievement in math, and no learning difficulties. Math fact errors were related to the severity of the math difficulties, not to reading status. Contrary to predictions, children with poorer reading, regardless of math achievement, committed more visually based errors. Operation switch errors were not systematically related to group membership. Teacher ratings of behavioral inattention were related to accuracy, math fact errors, and procedural bugs. The findings are discussed with respect to hypotheses about the cognitive origins of arithmetic errors and in relation to current discussions about how to conceptualize math disabilities. PMID:19380494

The Vision of Children with Learning Difficulties: The Role of the Teacher and Psychologist.

ERIC Educational Resources Information Center

Willis, Marilyn A.

1981-01-01

The role of optometry in the study of learning difficulties and the problems of interpreting research results in the fields of optometry and ophthalmology are discussed. Limitations of school visual screening are described, and it is suggested that many children with learning difficulties should be referred for a full clinical visual examination.…

A Few Steps along the Road? Promoting Support for Parents with Learning Difficulties

ERIC Educational Resources Information Center

Tarleton, Beth

2015-01-01

This paper considers the impact of research and development work around parenting by adults with a learning difficulty undertaken at the Norah Fry Research Centre (NFRC) since 2005. It discusses how our understanding of the support needs of parents with learning difficulties grew through an initial mapping study which led to the concept of…

Identifying College Students at Risk for Learning Disabilities: Evidence for Use of the Learning Difficulties Assessment in Postsecondary Settings

ERIC Educational Resources Information Center

Kane, Steven T.; Roy, Soma; Medina, Steffanie

2013-01-01

This article describes research supporting the use of the Learning Difficulties Assessment (LDA), a normed and no-cost, web-based survey that assesses difficulties with reading, writing, spelling, mathematics, listening, concentration, memory, organizational skills, sense of control, and anxiety in college students. Previous research has supported…

The Curriculum for Children with Severe and Profound Learning Difficulties at Stephen Hawking School

ERIC Educational Resources Information Center

Rayner, Matthew

2011-01-01

The increasing number of children with profound and multiple learning difficulties means that many schools for children with severe learning difficulties are having to review the curriculum that they offer. In addition, these schools are continuing to question whether a subject-based approach, in line with the National Curriculum, is the most…

The effects of task difficulty and workload on training

NASA Technical Reports Server (NTRS)

Mane, Amir; Wickens, Christopher D.

1986-01-01

Four hypotheses regarding the possible effects of workload and task difficulty on training are proposed. These are: (1) increased levels of task difficulty will facilitate learning to the extent that these increases are (a) resource loading and (b) intrinsic to the component task to be learned; (2) decrease of task difficulty will facilitate learning to the extent that these decreases (a) reduce the resource load and (b) are extrinsic of the component task to be learned; (3) the lerner's tendency to conserve resources may bead to the adoption of undesirable, short-term, low resource strategies early in training; and (4) the effect of changes in resource demand on learning will depend upon the similarity of the resource whose demand is changed to the resource involved in learning.

A Two Hundred Year History of Learning Disabilities

ERIC Educational Resources Information Center

Carlson, Shirley

2005-01-01

The purpose of this paper was to track the history of learning disabilities and collect intervention theories which might be helpful for adult college students suffering from any number of learning disabilities (LD). There is a vast difference between a learning difficulty and a learning disability; an individual with learning difficulty can learn…

Assessing college-level learning difficulties and "at riskness" for learning disabilities and ADHD: development and validation of the learning difficulties assessment.

PubMed

Kane, Steven T; Walker, John H; Schmidt, George R

2011-01-01

This article describes the development and validation of the Learning Difficulties Assessment (LDA), a normed and web-based survey that assesses perceived difficulties with reading, writing, spelling, mathematics, listening, concentration, memory, organizational skills, sense of control, and anxiety in college students. The LDA is designed to (a) map individual learning strengths and weaknesses, (b) provide users with a comparative sense of their academic skills, (c) integrate research in user-interface design to assist those with reading and learning challenges, and (d) identify individuals who may be at risk for learning disabilities and attention-deficit/hyperactivity disorder (ADHD) and who should thus be further assessed. Data from a large-scale 5-year study describing the instrument's validity as a screening tool for learning disabilities and ADHD are presented. This article also describes unique characteristics of the LDA including its user-interface design, normative characteristics, and use as a no-cost screening tool for identifying college students at risk for learning disorders and ADHD.

Why Is Math So Hard for Some Children? The Nature and Origins of Mathematical Learning Difficulties and Disabilities

ERIC Educational Resources Information Center

Berch, Daniel B., Ed; Mazzocco, Michele M.M., Ed.

2007-01-01

In order for schools to help students with learning difficulties and disabilities improve their achievement in mathematics, educators, researchers, practitioners, and policymakers need a better understanding of the evidence based on what is behind these students' difficulties in learning math. That is just what they will get with this landmark…

"May We Please Have Sex Tonight?"--People with Learning Difficulties Pursuing Privacy in Residential Group Settings

ERIC Educational Resources Information Center

Hollomotz, Andrea

2009-01-01

Many residential group settings for people with learning difficulties do not provide individuals with the private space in which they can explore their sexual relationships in a safe and dignified manner. Lack of agreed private spaces seriously infringes the individual's human rights. Many people with learning difficulties who lack privacy have no…

The Relationships between Indonesian Fourth Graders' Difficulties in Fractions and the Opportunity to Learn Fractions: A Snapshot of TIMSS Results

ERIC Educational Resources Information Center

Wijaya, Ariyadi

2017-01-01

This paper reports an exploration into Indonesian fourth graders' difficulties in fractions and their relation to the opportunity to learn fractions students got at schools. The concept of "opportunity to learn" is often considered as a framework to investigate possible reasons for students' difficulties. The data for this study was…

An Examination of the Effectiveness of Instruction in Which Pre-Service Mathematics Teachers Use Technology to Overcome Student Difficulties

ERIC Educational Resources Information Center

Yenmez, Arzu Aydogan

2017-01-01

It is seen that students face certain difficulties when learning the concepts and the relationships between them in the mathematics education that aims at enabling students to learn on the highest level. Identifying and eliminating these difficulties, helping students in the learning process and guiding them are among teachers' tasks. Overcoming…

Innovation Meets Performance Demands of Advanced Lithium-ion Batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Advancements in high capacity and low density battery technologies have led to a growing need for battery materials with greater charge capacity and therefore stability. NREL's developments in ALD and molecular layer MLD allow for thin film coatings to battery composite electrodes, which can improve battery lifespan, high charge capacity, and stability. Silicon, one of the best high-energy anode materials for Li-ion batteries, can experience capacity fade from volumetric expansion. Using MLD to examine how surface modification could stabilize silicon anode material in Li-ion batteries, researchers discovered a new reaction precursor that leads to a flexible surface coating that accommodatesmore » volumetric expansion of silicon electrodes.« less

Relating Difficulty in School Mathematics to Nature of Mathematics: Perception of High School Students from Kerala

ERIC Educational Resources Information Center

Gafoor, Kunnathodi Abdul; Sarabi, M. K.

2015-01-01

This study relates factors in nature of Mathematics and its teaching learning to student difficulties for diverse mathematics tasks. Descriptive survey was done on a sample of 300 high school students in Kerala with a questionnaire on difficulties in learning. Student perception of difficulty on 26 types of tasks, under five heads that students…

Numerical Investigations of Wave-Induced Mixing in Upper Ocean Layer

NASA Astrophysics Data System (ADS)

Guan, Changlong

2017-04-01

The upper ocean layer is playing an important role in ocean-atmosphere interaction. The typical characteristics depicting the upper ocean layer are the sea surface temperature (SST) and the mixed layer depth (MLD). So far, the existing ocean models tend to over-estimate SST and to under-estimate MLD, due to the inadequate mixing in the mixing layer, which is owing to that several processes related mixing in physics are ignored in these ocean models. The mixing induced by surface gravity wave is expected to be able to enhance the mixing in the upper ocean layer, and therefore the over-estimation of SST and the under-estimate of MLD could be improved by including wave-induced mixing. The wave-induced mixing could be accomplished by the physical mechanisms, such as wave breaking (WB), wave-induced Reynolds stress (WR), and wave-turbulence interaction (WT). The General Ocean Turbulence Model (GOTM) is employed to investigate the effects of the three mechanisms concerning wave-induced mixing. The numerical investigation is carried out for three turbulence closure schemes, say, k-epsilon, k-omega and Mellor-Yamada (1982), with the observational data from OSC Papa station and wave data from ECMWF. The mixing enhancement by various waved-induced mixing mechanisms is investigated and verified.

The sensitivity of primary productivity to intra-seasonal mixed layer variability in the sub-Antarctic Zone of the Atlantic Ocean

NASA Astrophysics Data System (ADS)

Joubert, W. R.; Swart, S.; Tagliabue, A.; Thomalla, S. J.; Monteiro, P. M. S.

2014-03-01

The seasonal cycle of primary productivity is impacted by seasonal and intra-seasonal dynamics of the mixed layer through the changing balance between mixing and buoyancy forcing, which regulates nutrient supply and light availability. Of particular recent interest is the role of synoptic scale events in supplying nutrients, particularly iron, to the euphotic zone in the Sub Antarctic Zone (SAZ), where phytoplankton blooms occur throughout summer. In this study, we present high resolution measurements of net community production (NCP) constrained by ΔO2/Ar ratios, and mixed layer depth (MLD) in the Atlantic SAZ. We found a non-linear relationship between NCP and MLD, with the highest and most variable NCP observed in shallow MLDs (< 45 m). We propose that NCP variability in the SAZ may be driven by alternating states of synoptic-scale deepening of the mixed layer, leading to the entrainment of iron (dFe), followed by restratification, allowing rapid growth in an iron replete, high light environment. Synoptic iron fluxes into the euphotic zone based on water column dFe profiles and high resolution glider MLD data, reveal a potentially significant contribution of "new iron" which could sustain NCP throughout summer. Future process studies will help elaborate these findings further.

Identifying Students' Difficulties When Learning Technical Skills via a Wireless Sensor Network

ERIC Educational Resources Information Center

Wang, Jingying; Wen, Ming-Lee; Jou, Min

2016-01-01

Practical training and actual application of acquired knowledge and techniques are crucial for the learning of technical skills. We established a wireless sensor network system (WSNS) based on the 5E learning cycle in a practical learning environment to improve students' reflective abilities and to reduce difficulties for the learning of technical…

What Makes Biology Learning Difficult and Effective: Students' Views

ERIC Educational Resources Information Center

Cimer, Atilla

2012-01-01

The present study aims to determine the biological topics that students have difficulties learning, the reasons why secondary school students have difficulties in learning biology, and ways to improve the effectiveness of students' biology learning. For these purposes, a self-administered questionnaire including three open-ended questions was…

Inter comparison of Tropical Indian Ocean features in different ocean reanalysis products

NASA Astrophysics Data System (ADS)

Karmakar, Ananya; Parekh, Anant; Chowdary, J. S.; Gnanaseelan, C.

2017-09-01

This study makes an inter comparison of ocean state of the Tropical Indian Ocean (TIO) in different ocean reanalyses such as global ocean data assimilation system (GODAS), ensemble coupled data assimilation (ECDA), ocean reanalysis system 4 (ORAS4) and simple ocean data assimilation (SODA) with reference to the in-situ buoy observations, satellite observed sea surface temperature (SST), EN4 analysis and ocean surface current analysis real time (OSCAR). Analysis of mean state of SST and sea surface salinity (SSS) reveals that ORAS4 is better comparable with satellite observations as well as EN4 analysis, and is followed by SODA, ECDA and GODAS. The surface circulation in ORAS4 is closer to OSCAR compared to the other reanalyses. However mixed layer depth (MLD) is better simulated by SODA, followed by ECDA, ORAS4 and GODAS. Seasonal evolution of error indicates that the highest deviation in SST and MLD over the TIO exists during spring and summer in GODAS. Statistical analysis with concurrent data of EN4 for the period of 1980-2010 supports that the difference and standard deviation (variability strength) ratio for SSS and MLD is mostly greater than one. In general the strength of variability is overestimated by all the reanalyses. Further comparison with in-situ buoy observations supports that MLD errors over the equatorial Indian Ocean (EIO) and the Bay of Bengal are higher than with EN4 analysis. Overall ORAS4 displays higher correlation and lower error among all reanalyses with respect to both EN4 analysis and buoy observations. Major issues in the reanalyses are the underestimation of upper ocean stability in the TIO, underestimation of surface current in the EIO, overestimation of vertical shear of current and improper variability in different oceanic variables. To improve the skill of reanalyses over the TIO, salinity vertical structure and upper ocean circulation need to be better represented in reanalyses.

Correlation of Clinical and Dosimetric Factors With Adverse Pulmonary Outcomes in Children After Lung Irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Venkatramani, Rajkumar, E-mail: rvenkatramani@chla.usc.edu; Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, California; Kamath, Sunil

Purpose: To identify the incidence and the risk factors for pulmonary toxicity in children treated for cancer with contemporary lung irradiation. Methods and Materials: We analyzed clinical features, radiographic findings, pulmonary function tests, and dosimetric parameters of children receiving irradiation to the lung fields over a 10-year period. Results: We identified 109 patients (75 male patients). The median age at irradiation was 13.8 years (range, 0.04-20.9 years). The median follow-up period was 3.4 years. The median prescribed radiation dose was 21 Gy (range, 0.4-64.8 Gy). Pulmonary toxic chemotherapy included bleomycin in 58.7% of patients and cyclophosphamide in 83.5%. The followingmore » pulmonary outcomes were identified and the 5-year cumulative incidence after irradiation was determined: pneumonitis, 6%; chronic cough, 10%; pneumonia, 35%; dyspnea, 11%; supplemental oxygen requirement, 2%; radiographic interstitial lung disease, 40%; and chest wall deformity, 12%. One patient died of progressive respiratory failure. Post-irradiation pulmonary function tests available from 44 patients showed evidence of obstructive lung disease (25%), restrictive disease (11%), hyperinflation (32%), and abnormal diffusion capacity (12%). Thoracic surgery, bleomycin, age, mean lung irradiation dose (MLD), maximum lung dose, prescribed dose, and dosimetric parameters between V{sub 22} (volume of lung exposed to a radiation dose ≥22 Gy) and V{sub 30} (volume of lung exposed to a radiation dose ≥30 Gy) were significant for the development of adverse pulmonary outcomes on univariate analysis. MLD, maximum lung dose, and V{sub dose} (percentage of volume of lung receiving the threshold dose or greater) were highly correlated. On multivariate analysis, MLD was the sole significant predictor of adverse pulmonary outcome (P=.01). Conclusions: Significant pulmonary dysfunction occurs in children receiving lung irradiation by contemporary techniques. MLD rather than prescribed dose should be used to perform risk stratification of patients receiving lung irradiation.« less

Functional image-guided stereotactic body radiation therapy planning for patients with hepatocellular carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsegmed, Uranchimeg; Kimura, Tomoki, E-mail: tkkimura@hiroshima-u.ac.jp; Nakashima, Takeo

The aim of the current planning study is to evaluate the ability of gadoxetate disodium-enhanced magnetic resonance imaging (EOB-MRI)–guided stereotactic body radiation therapy (SBRT) planning by using intensity-modulated radiation therapy (IMRT) techniques in sparing the functional liver tissues during SBRT for hepatocellular carcinoma. In this study, 20 patients with hepatocellular carcinoma were enrolled. Functional liver tissues were defined according to quantitative liver-spleen contrast ratios ≥ 1.5 on a hepatobiliary phase scan. Functional images were fused with the planning computed tomography (CT) images; the following 2 SBRT plans were designed using a “step-and-shoot” static IMRT technique for each patient: (1) an anatomicalmore » SBRT plan optimization based on the total liver; and (2) a functional SBRT plan based on the functional liver. The total prescribed dose was 48 gray (Gy) in 4 fractions. Dosimetric parameters, including dose to 95% of the planning target volume (PTV D{sub 95%}), percentages of total and functional liver volumes, which received doses from 5 to 30 Gy (V5 to V30 and fV5 to fV30), and mean doses to total and functional liver (MLD and fMLD, respectively) of the 2 plans were compared. Compared with anatomical plans, functional image-guided SBRT plans reduced MLD (mean: plan A, 5.5 Gy; and plan F, 5.1 Gy; p < 0.0001) and fMLD (mean: plan A, 5.4 Gy; and plan F, 4.9 Gy; p < 0.0001), as well as V5 to V30 and fV5 to fV30. No differences were noted in PTV coverage and nonhepatic organs at risk (OARs) doses. In conclusion, EOB-MRI–guided SBRT planning using the IMRT technique may preserve functional liver tissues in patients with hepatocellular carcinoma (HCC).« less

Mutation-linked, excessively tight interaction between the calmodulin binding domain and the C-terminal domain of the cardiac ryanodine receptor as a novel cause of catecholaminergic polymorphic ventricular tachycardia.

PubMed

Nishimura, Shigehiko; Yamamoto, Takeshi; Nakamura, Yoshihide; Kohno, Michiaki; Hamada, Yoriomi; Sufu, Yoko; Fukui, Go; Nanno, Takuma; Ishiguchi, Hironori; Kato, Takayoshi; Xu, Xiaojuan; Ono, Makoto; Oda, Tetsuro; Okuda, Shinichi; Kobayashi, Shigeki; Yano, Masafumi

2018-06-01

Ryanodine receptor (RyR2) is known to be a causal gene of catecholaminergic polymorphic ventricular tachycardia (CPVT), an important inherited disease. Some of the human CPVT-associated mutations have been found in a domain (4026-4172) that has EF hand motifs, the so-called calmodulin (CaM)-like domain (CaMLD). The purpose of this study was to investigate the underlying mechanism by which CPVT is induced by a mutation at CaMLD. A new N4103K/+ knock-in (KI) mice model was generated. Sustained ventricular tachycardia was frequently observed after infusion of caffeine plus epinephrine in KI mice. Endogenous CaM bound to RyR2 decreased even at baseline in isolated KI cardiomyocytes. Ca 2+ spark frequency (CaSpF) was much higher in KI cells than in wild-type cells. Addition of GSH-CaM (higher affinity CaM to RyR2) significantly decreased CaSpF. In response to isoproterenol, spontaneous Ca 2+ transient (SCaT) was frequently observed in intact KI cells. Incorporation of GSH-CaM into intact KI cells using a protein delivery kit decreased SCaT significantly. An assay using a quartz crystal microbalance technique revealed that mutated CaMLD peptide showed higher binding affinity to CaM binding domain (CaMBD) peptide. In the N4103K mutant, CaM binding affinity to RyR2 was significantly reduced regardless of beta-adrenergic stimulation. We found that this was caused by an abnormally tight interaction between CaMBD and mutated CaM-like domain (N4103K-CaMBD). Thus, CaMBD-CaMLD interaction may be a novel therapeutic target for treatment of lethal arrhythmia. Copyright © 2018 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Incorporating Single-nucleotide Polymorphisms Into the Lyman Model to Improve Prediction of Radiation Pneumonitis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tucker, Susan L., E-mail: sltucker@mdanderson.org; Li Minghuan; Xu Ting

2013-01-01

Purpose: To determine whether single-nucleotide polymorphisms (SNPs) in genes associated with DNA repair, cell cycle, transforming growth factor-{beta}, tumor necrosis factor and receptor, folic acid metabolism, and angiogenesis can significantly improve the fit of the Lyman-Kutcher-Burman (LKB) normal-tissue complication probability (NTCP) model of radiation pneumonitis (RP) risk among patients with non-small cell lung cancer (NSCLC). Methods and Materials: Sixteen SNPs from 10 different genes (XRCC1, XRCC3, APEX1, MDM2, TGF{beta}, TNF{alpha}, TNFR, MTHFR, MTRR, and VEGF) were genotyped in 141 NSCLC patients treated with definitive radiation therapy, with or without chemotherapy. The LKB model was used to estimate the risk ofmore » severe (grade {>=}3) RP as a function of mean lung dose (MLD), with SNPs and patient smoking status incorporated into the model as dose-modifying factors. Multivariate analyses were performed by adding significant factors to the MLD model in a forward stepwise procedure, with significance assessed using the likelihood-ratio test. Bootstrap analyses were used to assess the reproducibility of results under variations in the data. Results: Five SNPs were selected for inclusion in the multivariate NTCP model based on MLD alone. SNPs associated with an increased risk of severe RP were in genes for TGF{beta}, VEGF, TNF{alpha}, XRCC1 and APEX1. With smoking status included in the multivariate model, the SNPs significantly associated with increased risk of RP were in genes for TGF{beta}, VEGF, and XRCC3. Bootstrap analyses selected a median of 4 SNPs per model fit, with the 6 genes listed above selected most often. Conclusions: This study provides evidence that SNPs can significantly improve the predictive ability of the Lyman MLD model. With a small number of SNPs, it was possible to distinguish cohorts with >50% risk vs <10% risk of RP when they were exposed to high MLDs.« less

A Novel Phosphatidylinositol 4,5-Bisphosphate Binding Domain Mediates Plasma Membrane Localization of ExoU and Other Patatin-like Phospholipases*

PubMed Central

Tyson, Gregory H.; Halavaty, Andrei S.; Kim, Hyunjin; Geissler, Brett; Agard, Mallory; Satchell, Karla J.; Cho, Wonhwa; Anderson, Wayne F.; Hauser, Alan R.

2015-01-01

Bacterial toxins require localization to specific intracellular compartments following injection into host cells. In this study, we examined the membrane targeting of a broad family of bacterial proteins, the patatin-like phospholipases. The best characterized member of this family is ExoU, an effector of the Pseudomonas aeruginosa type III secretion system. Upon injection into host cells, ExoU localizes to the plasma membrane, where it uses its phospholipase A2 activity to lyse infected cells. The targeting mechanism of ExoU is poorly characterized, but it was recently found to bind to the phospholipid phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), a marker for the plasma membrane of eukaryotic cells. We confirmed that the membrane localization domain (MLD) of ExoU had a direct affinity for PI(4,5)P2, and we determined that this binding was required for ExoU localization. Previously uncharacterized ExoU homologs from Pseudomonas fluorescens and Photorhabdus asymbiotica also localized to the plasma membrane and required PI(4,5)P2 for this localization. A conserved arginine within the MLD was critical for interaction of each protein with PI(4,5)P2 and for localization. Furthermore, we determined the crystal structure of the full-length P. fluorescens ExoU and found that it was similar to that of P. aeruginosa ExoU. Each MLD contains a four-helical bundle, with the conserved arginine exposed at its cap to allow for interaction with the negatively charged PI(4,5)P2. Overall, these findings provide a structural explanation for the targeting of patatin-like phospholipases to the plasma membrane and define the MLD of ExoU as a member of a new class of PI(4,5)P2 binding domains. PMID:25505182

Novel processing to produce polymer/ceramic nanocomposites by atomic layer deposition

NASA Astrophysics Data System (ADS)

Liang, Xinhua

Polymeric materials can be greatly influenced by nanoscale inclusions of inorganic materials. The main goal of this thesis is to fabricate novel polymer/ceramic composite materials for two different applications using atomic layer deposition (ALD) or molecular layer deposition (MLD) methods. One is to produce well-dispersed polymer/ceramic nanocomposites with improved barrier properties for packaging applications. The other is to produce porous polymer/ceramic composites with improved bioactivity for tissue engineering applications. ALD has been successfully utilized for the conformal and uniform deposition of ultra-thin alumina and titania films on primary micron-sized polymer particles. The mechanism to initiate alumina and titania ALD on polymer particles without chemical functional groups was confirmed. A nucleation period was needed for both alumina and titania ALD on high density polyethylene (HDPE) particles and no nucleation period was needed for alumina ALD on polymethyl methacrylate particles. Titania ALD films deposited at low temperatures had an amorphous structure and showed much weaker photoactivity than common pigment-grade anatase TiO2 particles. Highly uniform and conformal ultra-thin aluminum alkoxide (alucone) polymer films were deposited on primary silica and titania nanoparticles using MLD in a fluidized bed reactor. The deposition chemistry and properties of alucone MLD films were investigated. The photoactivity of pigment-grade TiO2 particles was quenched after 20 cycles of an alucone MLD film, but the films shrank and decomposed in the presence of water, which decreased the passivation effect of the photoactivity of TiO2 particles. Well-dispersed polymer/ceramic nanocomposites were obtained by extruding alumina ALD coated HDPE particles. The diffusion coefficient of the fabricated nanocomposite membranes can be reduced by half with the inclusion of 7.3 vol.% alumina flakes. However, a corresponding increase in permeability was also observed due to the voids formed at or near the interface of the polymer and alumina flakes during the extrusion process. Efforts to improve the barrier properties of the membranes included 3-aminopropyltriethoxysilane treatment and coating alucone MLD films on alumina coated particles prior to extrusion. The porous polymer/ceramic particles were synthesized by depositing ultra-thin alumina or titania films on highly porous poly(styrene-divinylbenzene) particles using a low-temperature ALD process. Analytical characterization revealed that conformal alumina and titania films were grown on internal and external polymer particle surfaces, and the pore filling mechanism was a uniform coating of the pore walls. The ALD layers can improve the bioactivity and protein adsorption of the polymer substrates.

Genetics - Are There Inherent Learning Difficulties?

ERIC Educational Resources Information Center

Longden, Bernard

1982-01-01

Sources of misconceptions and learning difficulties were identified by interviewing academically sound A-level students (N=10) who were having difficulties with genetics. Indicates misconceptions were related to nature of concepts used in genetics, such as frequent representation of meiosis by fixed inanimate stage diagrams and to instructional…

Colorado Learning Difficulties Questionnaire:Validation of a parent-report screening measure

PubMed Central

Willcutt, Erik G.; Boada, Richard; Riddle, Margaret W.; Chhabildas, Nomita; DeFries, John C.; Pennington, Bruce F.

2011-01-01

This study evaluated the internal structure and convergent and discriminant evidence for the Colorado Learning Difficulties Questionnaire (CLDQ), a 20-item parent-report rating scale that was developed to provide a brief screening measure for learning difficulties. CLDQ ratings were obtained from parents of children in two large community samples and two samples from clinics that specialize in the assessment of learning disabilities and related disorders (total N = 8,004). Exploratory and confirmatory factor analyses revealed five correlated but separable dimensions that were labeled reading, math, social cognition, social anxiety, and spatial difficulties. Results revealed strong convergent and discriminant evidence for the CLDQ Reading scale, suggesting that this scale may provide a useful method to screen for reading difficulties in both research studies and clinical settings. Results are also promising for the other four CLDQ scales, but additional research is needed to refine each of these measures. PMID:21574721

The Effects of Generative Learning Strategy Prompts and Metacognitive Feedback on Learners' Self-Regulation, Generation Process, and Achievement

ERIC Educational Resources Information Center

Lee, Hyeon Woo

2008-01-01

Instructional designers need to understand the internal processes of learning, identify learners' cognitive difficulties with those processes, and create strategies to help learners overcome those difficulties. Generative learning theory, one conception of human learning about cognitive functioning and process, emphasizes that meaningful learning…

Changing How We Think, Changing How We Learn: Scaffolding Executive Function Processes for Students with Learning Disabilities

ERIC Educational Resources Information Center

Rosen, Sonia M.; Boyle, Joseph R.; Cariss, Kaitlyn; Forchelli, Gina A.

2014-01-01

Students with learning disabilities have been reported to have difficulty in a number of different executive function processes that affect their academic performance (Singer & Bashir, 1999). Executive function difficulties for students with learning disabilities have been implicated as the reason why these students struggle with complex…

Pre-Service Physics Teachers' Comprehension of Quantum Mechanical Concepts

ERIC Educational Resources Information Center

Didis, Nilufer; Eryilmaz, Ali; Erkoc, Sakir

2010-01-01

When quantum theory caused a paradigm shift in physics, it introduced difficulties in both learning and teaching of physics. Because of its abstract, counter-intuitive and mathematical structure, students have difficulty in learning this theory, and instructors have difficulty in teaching the concepts of the theory. This case study investigates…

Allogeneic Bone Marrow Transplant for Inherited Metabolic Disorders

ClinicalTrials.gov

2018-01-09

Mucopolysaccharidosis; Hurler Syndrome; Hunter Syndrome; Maroteaux-Lamy Syndrome; Sly Syndrome; Alpha Mannosidosis; Fucosidosis; Aspartylglucosaminuria; Adrenoleukodystrophy (ALD); Krabbe Disease; Metachromatic Leukodystrophy (MLD); Sphingolipidoses; Peroxisomal Disorders

The Role of Metacognitive Reading Strategies, Metacognitive Study and Learning Strategies, and Behavioral Study and Learning Strategies in Predicting Academic Success in Students with and without a History of Reading Difficulties

ERIC Educational Resources Information Center

Chevalier, Thérèse M.; Parrila, Rauno; Ritchie, Krista C.; Deacon, S. Hélène

2017-01-01

We examined the self-reported use of reading, study, and learning strategies in university students with a history of reading difficulties (HRD; n = 77) and with no history of reading difficulties (NRD; n = 295). We examined both between-groups differences in strategy use and strategy use as a predictive measure of academic success. Participants…

Perception of Contingency and Mental Retardation.

ERIC Educational Resources Information Center

DeVellis, Robert F.; McCauley, Charley

1979-01-01

It is argued that the general learning difficulties exhibited by mentally retarded persons are similar in many respects to the learning difficulties of nonretarded persons who are in a state of learned helplessness (M. Seligman, 1975) or who are external in locus of control orientation. (Author)

Meaning-Led Learning for Pupils with Severe and Profound and Multiple Learning Difficulties

ERIC Educational Resources Information Center

Goss, Phil

2006-01-01

This paper proposes that learning and teaching for pupils with severe and profound and multiple learning difficulties could be enhanced by a closer focus on emotional factors and on the careful identification of what is meaningful for them. Phil Goss, senior lecturer in counselling and psychotherapy at the University of Central Lancashire draws on…

Teachers' Perceptions of the Concomitance of Emotional Behavioural Difficulties and Learning Disabilities in Children Referred for Learning Disabilities in Oman

ERIC Educational Resources Information Center

Emam, Mahmoud Mohamed; Kazem, Ali Mahdi

2015-01-01

Research has documented overlapping and coexisting characteristics of learning disabilities (LD) and emotional and behavioural difficulties (EBD). Such concomitance may impact teacher referrals of children at risk for LD which in turn may influence service delivery. Using the Learning Disabilities Diagnostic Inventory (LDDI) and the Strengths and…

Reflections on providing sport science support for athletes with learning difficulties.

PubMed

Hills, Laura; Utley, Andrea

2010-01-01

To highlight the benefits and the need for sport science support for athletes with learning difficulties, and to reflect on our experience of working with the GB squad for athletes with learning difficulties. A review of key and relevant literature is presented, followed by a discussion of the sport science support provision and the issues that emerged in working with athletes with learning difficulties. Pre- and post- physiological tests along with evaluations of athletes' potential to benefit from sport psychology support were conducted. The aim of these tests was to provide information for the athletes and the coaches on fitness levels, to use this information to plan future training, and to identify how well the performance could be enhanced. A case study is presented for one athlete, who had competed in distance events. The focus is the psychological support that was provided. It is clear that athletes with learning difficulties require the same type of sports science support as their mainstream peers. However, sport scientists will need to consider ways to extend their practice in order to provide the appropriate level of support.

Learner's Learning Experiences & Difficulties towards (ESL) among UKM Undergraduates

ERIC Educational Resources Information Center

Maarof, Nooreiny; Munusamy, Indira Malani A/P

2015-01-01

This paper aims to investigate the learners learning experiences and difficulties of ESL among the UKM undergraduates. This study will be focusing on identifying the factors behind Malaysian undergraduate's experiences and also their difficulties in the English as Second Language (ESL) classroom. This paper discusses some of the issues of English…

Students' Emotional and Behavioral Difficulties: The Role of Teachers' Social and Emotional Learning and Teacher-Student Relationships

ERIC Educational Resources Information Center

Poulou, Maria S.

2017-01-01

This study investigates how teachers? perceptions of Emotional Intelligence (EI), Social and Emotional Learning (SEL) skills, and teacher-student relationships relate to students? emotional and behavioral difficulties. We examined teachers and students? perceptions of students? emotional and behavioral difficulties and the degree of agreement…

A Review of Factors Associated with Young Children's Difficulties in Acquiring Age-Appropriate Mathematical Abilities.

ERIC Educational Resources Information Center

Evans, Roy; Goodman, Kathy

1995-01-01

Analyzes the factors behind children's learning difficulties in mathematics from three kinds of characteristics: characteristics of the child, of the teacher/teaching method, and of the subject. Suggests that perceived underachievement comes mainly from poor self-image, learning style, poor language skills, dyslexic-type difficulties, lack of…

Initial Understandings of Fraction Concepts Evidenced by Students with Mathematics Learning Disabilities and Difficulties: A Framework

ERIC Educational Resources Information Center

Hunt, Jessica H.; Welch-Ptak, Jasmine J.; Silva, Juanita M.

2016-01-01

Documenting how students with learning disabilities (LD) initially conceive of fractional quantities, and how their understandings may align with or differ from students with mathematics difficulties, is necessary to guide development of assessments and interventions that attach to unique ways of thinking or inherent difficulties these students…

Learners' Listening Comprehension Difficulties in English Language Learning: A Literature Review

ERIC Educational Resources Information Center

Gilakjani, Abbas Pourhosein; Sabouri, Narjes Banou

2016-01-01

Listening is one of the most important skills in English language learning. When students listen to English language, they face a lot of listening difficulties. Students have critical difficulties in listening comprehension because universities and schools pay more attention to writing, reading, and vocabulary. Listening is not an important part…

Player Modeling for Intelligent Difficulty Adjustment

NASA Astrophysics Data System (ADS)

Missura, Olana; Gärtner, Thomas

In this paper we aim at automatically adjusting the difficulty of computer games by clustering players into different types and supervised prediction of the type from short traces of gameplay. An important ingredient of video games is to challenge players by providing them with tasks of appropriate and increasing difficulty. How this difficulty should be chosen and increase over time strongly depends on the ability, experience, perception and learning curve of each individual player. It is a subjective parameter that is very difficult to set. Wrong choices can easily lead to players stopping to play the game as they get bored (if underburdened) or frustrated (if overburdened). An ideal game should be able to adjust its difficulty dynamically governed by the player’s performance. Modern video games utilise a game-testing process to investigate among other factors the perceived difficulty for a multitude of players. In this paper, we investigate how machine learning techniques can be used for automatic difficulty adjustment. Our experiments confirm the potential of machine learning in this application.

Web-Based Technology for Children with Learning Disabilities

ERIC Educational Resources Information Center

Kumar, S. Praveen; Raja, B. William Dharma

2010-01-01

Individuals with special educational needs may face difficulties in acquiring basic skills needed for learning such as reading, spelling, writing, speaking, understanding, listening, thinking or arithmetic. The difficulties they face in the learning process have begun to attract serious attention throughout the globe. They suffer from severe…

Human urine-derived stem cells play a novel role in the treatment of STZ-induced diabetic mice.

PubMed

Zhao, Tianxue; Luo, Deng; Sun, Yun; Niu, Xin; Wang, Yang; Wang, Chen; Jia, Weiping

2018-04-19

Human urine-derived stem cells (hUSCs) are a potential stem cell source for cell therapy. However, the effect of hUSCs on glucose metabolism regulation in type 1 diabetes was not clear. Therefore, the aim of the study was to evaluate whether hUSCs have protective effect on streptozotocin (STZ)-induced diabetes. hUSCs were extracted and cultivated with a special culture medium. Flow cytometry analysis was applied to detect cell surface markers. BALB/c male nude mice were either injected with high-dose STZ (HD-STZ) or multiple low-dose STZ (MLD-STZ). Serum and pancreatic insulin were measured, islet morphology and its vascularization were investigated. hUSCs highly expressed CD29, CD73, CD90 and CD146, and could differentiate into, at least, bone and fat in vitro. Transplantation of hUSCs into HD-STZ treated mice prolonged the median survival time and improved their blood glucose, and into those with MLD-STZ improved the glucose tolerance, islet morphology and increased the serum and pancreas insulin content. Furthermore, CD31 expression increased significantly in islets of BALB/c nude mice treated with hUSCs compared to those of un-transplanted MLD-STZ mice. hUSCs could improve the median survival time and glucose homeostasis in STZ-treated mice through promoting islet vascular regeneration and pancreatic beta-cell survival.

Posture and activity recognition and energy expenditure estimation in a wearable platform.

PubMed

Sazonov, Edward; Hegde, Nagaraj; Browning, Raymond C; Melanson, Edward L; Sazonova, Nadezhda A

2015-07-01

The use of wearable sensors coupled with the processing power of mobile phones may be an attractive way to provide real-time feedback about physical activity and energy expenditure (EE). Here, we describe the use of a shoe-based wearable sensor system (SmartShoe) with a mobile phone for real-time recognition of various postures/physical activities and the resulting EE. To deal with processing power and memory limitations of the phone, we compare the use of support vector machines (SVM), multinomial logistic discrimination (MLD), and multilayer perceptrons (MLP) for posture and activity classification followed by activity-branched EE estimation. The algorithms were validated using data from 15 subjects who performed up to 15 different activities of daily living during a 4-h stay in a room calorimeter. MLD and MLP demonstrated activity classification accuracy virtually identical to SVM (∼ 95%) while reducing the running time and the memory requirements by a factor of >10 3. Comparison of per-minute EE estimation using activity-branched models resulted in accurate EE prediction (RMSE = 0.78 kcal/min for SVM and MLD activity classification, 0.77 kcal/min for MLP versus RMSE of 0.75 kcal/min for manual annotation). These results suggest that low-power computational algorithms can be successfully used for real-time physical activity monitoring and EE estimation on a wearable platform.

Changes in tissue water and indentation resistance of lymphedematous limbs accompanying low level laser therapy (LLLT) of fibrotic skin.

PubMed

Mayrovitz, H N; Davey, S

2011-12-01

Our goal was to determine effects of low-level-laser-therapy (LLLT) on skin water and tissue indentation resistance (TIR) in patients with arm (N = 38) or leg (N = 38) lymphedema. Skin water was determined from tissue dielectric constant (TDC) measurements and TIR determined from measurements of force resulting from tissue indentations of 3-4 mm. A limb-location with fibrosis was identified by palpation and treated with an LLLT device for one minute at each of five points within a 3 cm2 area. TDC and TIR at these sites and corresponding sites on the contralateral limb were measured prior to LLLT (pre-LLLT), immediately after LLLT (post-LLLT) and after a manual lymphatic drainage (MLD) session (post-MLD). Results, from arms and legs, showed that post-LLLT values of TIR and TDC were significantly less than pre-LLLT. TIR values remained significantly reduced at post-MLD whereas TDC values were not significantly different from pre-LLLT values. On follow-up visit, 17 previously LLLT treated legs were sham treated with an inactive LLLT unit and measurements replicated. A TIR and TDC change-pattern similar to that obtained with the active LLLT was obtained, but sham-related reductions in TIR and TDC immediately post sham-treatment were significantly less than achieved with the prior active LLLT treatment.

A comparison of hydrographically and optically derived mixed layer depths

USGS Publications Warehouse

Zawada, D.G.; Zaneveld, J.R.V.; Boss, E.; Gardner, W.D.; Richardson, M.J.; Mishonov, A.V.

2005-01-01

Efforts to understand and model the dynamics of the upper ocean would be significantly advanced given the ability to rapidly determine mixed layer depths (MLDs) over large regions. Remote sensing technologies are an ideal choice for achieving this goal. This study addresses the feasibility of estimating MLDs from optical properties. These properties are strongly influenced by suspended particle concentrations, which generally reach a maximum at pycnoclines. The premise therefore is to use a gradient in beam attenuation at 660 nm (c660) as a proxy for the depth of a particle-scattering layer. Using a global data set collected during World Ocean Circulation Experiment cruises from 1988-1997, six algorithms were employed to compute MLDs from either density or temperature profiles. Given the absence of published optically based MLD algorithms, two new methods were developed that use c660 profiles to estimate the MLD. Intercomparison of the six hydrographically based algorithms revealed some significant disparities among the resulting MLD values. Comparisons between the hydrographical and optical approaches indicated a first-order agreement between the MLDs based on the depths of gradient maxima for density and c660. When comparing various hydrographically based algorithms, other investigators reported that inherent fluctuations of the mixed layer depth limit the accuracy of its determination to 20 m. Using this benchmark, we found a ???70% agreement between the best hydrographical-optical algorithm pairings. Copyright 2005 by the American Geophysical Union.

The Role of Parenting for the Adjustment of Children with and without Learning Disabilities: A Person-Oriented Approach

ERIC Educational Resources Information Center

Barkauskiene, Rasa

2009-01-01

A person-oriented approach was used to examine the role of parenting in the associations between single learning disabilities and multiple learning disabilities and the adjustment difficulties in 8-11-year-olds. The results revealed that multiple, but not single, learning disabilities were associated with greater difficulties in emotional and…

Developing Pedagogical Expertise in Modern Language Learning and Specific Learning Difficulties through Collaborative and Open Educational Practices

ERIC Educational Resources Information Center

Gallardo, Matilde; Heiser, Sarah; Arias McLaughlin, Ximena

2017-01-01

This paper analyses teachers' engagement with collaborative and open educational practices to develop their pedagogical expertise in the field of modern language (ML) learning and specific learning difficulties (SpLD). The study analyses the findings of a staff development initiative at the Department of Languages, Open University, UK, in 2013,…

Making It Work: Embedding a Supported Employment Approach in Vocational Education and Training for People with Learning Difficulties

ERIC Educational Resources Information Center

Jacobsen, Yola

2010-01-01

The "Making it Work" book is for practitioners and managers working with people with learning difficulties in FE colleges, adult and community learning services, work-based learning and voluntary sector organisations. This book was produced as a result of a two-year project funded by the Department of Health. It provides information…

The Effectiveness of Project-Based Learning on Pupils with Learning Difficulties Regarding Academic Performance, Group Work and Motivation

ERIC Educational Resources Information Center

Filippatou, Diamanto; Kaldi, Stavroula

2010-01-01

This study focuses upon the effectiveness of project-based learning on primary school pupils with learning difficulties regarding their academic performance and attitudes towards self efficacy, task value, group work and teaching methods applied. The present study is a part of a larger one that included six Greek fourth-grade primary school…

Foreign Language Learning Difficulties in Italian Children: Are They Associated with Other Learning Difficulties?

ERIC Educational Resources Information Center

Ferrari, Marcella; Palladino, Paola

2007-01-01

A group of seventh- and eighth-grade Italian students with low achievement (LA) in learning English as a foreign language (FL) was selected and compared to a group with high achievement (HA) in FL learning. The two groups were matched for age and nonverbal intelligence. Two experiments were conducted to examine the participants' verbal and…

What is the optimal task difficulty for reinforcement learning of brain self-regulation?

PubMed

Bauer, Robert; Vukelić, Mathias; Gharabaghi, Alireza

2016-09-01

The balance between action and reward during neurofeedback may influence reinforcement learning of brain self-regulation. Eleven healthy volunteers participated in three runs of motor imagery-based brain-machine interface feedback where a robot passively opened the hand contingent to β-band modulation. For each run, the β-desynchronization threshold to initiate the hand robot movement increased in difficulty (low, moderate, and demanding). In this context, the incentive to learn was estimated by the change of reward per action, operationalized as the change in reward duration per movement onset. Variance analysis revealed a significant interaction between threshold difficulty and the relationship between reward duration and number of movement onsets (p<0.001), indicating a negative learning incentive for low difficulty, but a positive learning incentive for moderate and demanding runs. Exploration of different thresholds in the same data set indicated that the learning incentive peaked at higher thresholds than the threshold which resulted in maximum classification accuracy. Specificity is more important than sensitivity of neurofeedback for reinforcement learning of brain self-regulation. Learning efficiency requires adequate challenge by neurofeedback interventions. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Blended Learning for College Students with English Reading Difficulties

ERIC Educational Resources Information Center

Yang, Yu-Fen

2012-01-01

Most previous studies in blended learning simply involved on-site and online instruction without considering students' control of their own learning in these two different modalities. The purpose of this study was to investigate how college students with English reading difficulties integrate their conceptions of and approaches to blended learning…

Too Late at Eight: Prevention and Intervention, Young Children's Learning Difficulties.

ERIC Educational Resources Information Center

Atkinson, Joan K., Ed.

The report contains 15 papers given at a 1979 Australian conference on prevention and intervention with young children at risk of developmental and learning difficulties. Papers have the following titles and authors: "Prevention and Early Amelioration of Developmental and Learning Disabilities: Progress, Problems and Prospects" (W.…

Ranking the Difficulty Level of the Knowledge Units Based on Learning Dependency

ERIC Educational Resources Information Center

Liu, Jun; Sha, Sha; Zheng, Qinghua; Zhang, Wei

2012-01-01

Assigning difficulty level indicators to the knowledge units helps the learners plan their learning activities more efficiently. This paper focuses on how to use the topology of a knowledge map to compute and rank the difficulty levels of knowledge units. Firstly, the authors present the hierarchical structure and properties of the knowledge map.…

A Review of the Approaches Investigating the Post-16 Transition of Young Adults with Learning Difficulties

ERIC Educational Resources Information Center

Carroll, Catherine

2015-01-01

Investigations into the lives and transition from compulsory schooling of young adults with a disability, including a learning difficulty (LD), are increasing. The emerging consensus is one which points to this group of young people experiencing greater difficulties and poorer outcomes compared to the general population. How these investigations…

Lessons from Preventing Reading Difficulties in Young Children for Adult Learning and Literacy

ERIC Educational Resources Information Center

Snow, Catherine E.; Strucker, John

1999-01-01

In the spring of 1998 the National Research Council released a report, Preventing Reading Difficulties in Young Children for Adult Learning and Literacy (PRD). PRD was written with the goal of contributing to the prevention of reading difficulties by documenting the contributions of research to an understanding of reading development and the…

Safe and Durable High-Temperature Lithium-Sulfur Batteries via Molecular Layer Deposited Coating.

PubMed

Li, Xia; Lushington, Andrew; Sun, Qian; Xiao, Wei; Liu, Jian; Wang, Biqiong; Ye, Yifan; Nie, Kaiqi; Hu, Yongfeng; Xiao, Qunfeng; Li, Ruying; Guo, Jinghua; Sham, Tsun-Kong; Sun, Xueliang

2016-06-08

Lithium-sulfur (Li-S) battery is a promising high energy storage candidate in electric vehicles. However, the commonly employed ether based electrolyte does not enable to realize safe high-temperature Li-S batteries due to the low boiling and flash temperatures. Traditional carbonate based electrolyte obtains safe physical properties at high temperature but does not complete reversible electrochemical reaction for most Li-S batteries. Here we realize safe high temperature Li-S batteries on universal carbon-sulfur electrodes by molecular layer deposited (MLD) alucone coating. Sulfur cathodes with MLD coating complete the reversible electrochemical process in carbonate electrolyte and exhibit a safe and ultrastable cycle life at high temperature, which promise practicable Li-S batteries for electric vehicles and other large-scale energy storage systems.

Iron-Terephthalate Coordination Network Thin Films Through In-Situ Atomic/Molecular Layer Deposition.

PubMed

Tanskanen, A; Karppinen, M

2018-06-12

Iron terephthalate coordination network thin films can be fabricated using the state-of-the-art gas-phase atomic/molecular layer deposition (ALD/MLD) technique in a highly controlled manner. Iron is an Earth-abundant and nonhazardous transition metal, and with its rich variety of potential applications an interesting metal constituent for the inorganic-organic coordination network films. Our work underlines the role of the metal precursor used when aiming at in-situ ALD/MLD growth of crystalline inorganic-organic thin films. We obtain crystalline iron terephthalate films when FeCl 3 is employed as the iron source whereas depositions based on the bulkier Fe(acac) 3 precursor yield amorphous films. The chemical composition and structure of the films are investigated with GIXRD, XRR, FTIR and XPS.

True coronary bifurcation lesions: meta-analysis and review of literature.

PubMed

Athappan, Ganesh; Ponniah, Thirumalaikolundiusubramanian; Jeyaseelan, Lakshmanan

2010-02-01

Percutaneous intervention of true coronary bifurcation lesions is challenging. Based on the results of randomized trials and registry data, the approach of stenting of main vessel only with balloon dilatation of the side branch has become the default approach for false bifurcation lesions except when a complication occurs or in cases of suboptimal result. However, the optimal stenting strategy for true coronary bifurcation lesions - to stent or not to stent the side branch - is still a matter of debate. The purpose of this study was, therefore, to compare the clinical and angiographic outcomes of the double stent technique (stenting of the main branch and side branch) over the single stent technique (stenting of main vessel only with balloon dilatation of the side branch) for treatment of true coronary bifurcation lesions, with drug-eluting stents (DES). Comparative studies published between January 2000 and February 2009 of the double stent technique vs. single stent technique with DES for true coronary bifurcations were identified using an electronic search and reviewed using a random effects model. The primary endpoints of our study were side-branch and main-branch restenoses, all-cause mortality, myocardial infarction (MI) and target lesion revascularization (TLR) at longest available follow-up. The secondary endpoints of our analysis were postprocedural minimal luminal diameter (MLD) of the side branch and main branch, follow-up MLD of side branch and main branch and stent thrombosis. Heterogeneity was assessed and sensitivity analysis was performed to test the robustness of the overall summary odds ratios (ORs). Five studies comprising 1145 patients (616 single stent and 529 double stent) were included in the analysis. Three studies were randomized comparisons between the two techniques for true coronary bifurcation lesions. Incomplete reporting of data in the primary studies was common. The lengths of clinical and angiographic follow-up ranged between 6 and 12 months and 6 and 7 months, respectively. Postprocedural MLD of the side branch was significantly smaller in the single stent group [standardized mean difference (SMD) -0.71, 95% CI -0.88 to -0.54, P < 0.000, I2 = 0%]. The odds of side-branch restenosis (OR 1.11, 95% CI 0.47-2.67, P = 0.81, I2 = 76%), main-branch restenois (OR 0.88, 95% CI 0.56-1.39, P = 0.58, I = 0%), all-cause mortality (OR 0.52, 95% CI 0.11-2.45, P = 0.41, I2 = 0%), MI (OR 0.92, 95% CI 0.34-2.54, P = 0.87, I = 49%) and TLR (OR 0.87, 95% CI 0.46-1.65, P = 0.68, I2 = 0%) were similar between the two groups. Postprocedural MLD of the main branch [standardized mean difference (SMD) -0.08, 95% CI -0.42 to -0.26, P < 0.65, I2 = 67%], follow-up MLD of side branch (SMD -0.19, 95% CI -0.40 to 0.01, P < 0.31, I2 = 15%) and main branch MLD (SMD 0.17, 95% CI -0.18 to 0.542, P < 0.35, I2 = 65%) were also similar between the two groups. In patients undergoing percutaneous coronary intervention (PCI) for true coronary bifurcations, there is no added advantage of stenting both branches as compared with a conventional one-stent strategy. The results, however, need to be interpreted considering the poor study methods and/or poor quality of reporting in publications. We propose to move forward and consider the conduct of more systematic, well-designed and scientific trials to investigate the treatment of true coronary bifurcation lesions.

SU-C-210-01: Are Clinically Relevant Dosimetric Endpoints Significantly Better with Gating of Lung SBRT Vs. ITV-Based Treatment?: Results of a Large Cohort Investigation Analyzing Predictive Dosimetric Indicators as a Function of Tumor Volume and Motion Amplitude

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, J; Zhao, B; Ajlouni, M

2015-06-15

Purpose: To quantitatively compare patient internal target volume (ITV)-based plans with retrospectively generated gated plans to evaluate potential dosimetric improvements in lung toxicity from gated radiotherapy. Methods: Evaluation was conducted for 150 stereotactic body radiation therapy (SBRT) treatment plans for 128 early-stage (T1–T3, <5cm) NSCLC patients. PTV margins were: ITV+5 mm (ITV-plan) and GTV+5 mm (Gated-plan). ITV-based and gated treatment plans were compared on the same free-breathing CT. ITV-based plan constraints were used to re-optimize and recalculate new gated plans. Plans were generated for 3 fractionation regimens: 3×18Gy, 4×12Gy (original), and 5×10Gy. Physical dose was converted to equivalent dose inmore » 2Gy fractions (EQD2), which was used to determine mean lung dose (MLD) and percent volume of lung receiving ≥20Gy (V20). MLD and V20 differences between gating and ITV-based plans were analyzed as a function of both three-dimensional (3D) motion and tumor volume. The low dose region, V5, was also evaluated. Results: MLD and V20 differences between gated and ITV-based plans were larger for lower (1.48±1.32Gy and 1.44±1.29%) than for upper lobe tumors (0.89±0.74Gy and 0.92±0.71%) due to smaller tumor motion (2.9±3.4mm) compared to lower lobe tumors (8.1±6.1mm). Average differences of <1–2% were noted in V5 between ITV and gated plans. Dosimetric differences between gating and ITV-based methods increased with increasing tumor motion and decreasing tumor volume. Overall, average MLD (8.04±3.92Gy) and V20 (8.29±4.33%) values for ITV-based plans were already well below clinical guidelines, even for the 3×18Gy dose scheme, for which largest differences were noted relative to gated plans. Similar results were obtained for 5×10Gy and 4×12Gy regimens. Conclusion: Clinically relevant improvement in pulmonary toxicity, based on predictors of radiation pneumonitis (MLD and V20) was not generally observed, though improvement for tumors with 3D motion >15 mm, mainly concentrated in peripheral lower lobe tumors, may be considered clinically relevant. Work supported in part by a grant from Varian Medical systems, Palo Alto, CA.« less

Helping Students Draw Correct Free-Body Diagrams

ERIC Educational Resources Information Center

Lee, Albert

2017-01-01

As physics instructors, we try to help our students learn physics. But most of us begin to realize that our students are not learning as much as we hope they would. As we listen to our students, we begin to see some of their difficulties. Some of their difficulties are expected, but some are unexpected. One such difficulty is drawing the force…

A Study on the Difficulties of Learning Phase Transition in Object-Oriented Analysis and Design from the Viewpoint of Semantic Distance

ERIC Educational Resources Information Center

Shin, Shin-Shing

2015-01-01

Students in object-oriented analysis and design (OOAD) courses typically encounter difficulties transitioning from object-oriented analysis (OOA) to logical design (OOLD). This study conducted an empirical experiment to examine these learning difficulties by evaluating differences between OOA-to-OOLD and OOLD-to-object-oriented-physical-design…

Self-Control of Task Difficulty during Training Enhances Motor Learning of a Complex Coincidence-Anticipation Task

ERIC Educational Resources Information Center

Andrieux, Mathieu; Danna, Jeremy; Thon, Bernard

2012-01-01

The aim of the present work was to analyze the influence of self-controlled task difficulty on motor learning. Participants had to intercept three targets falling at different velocities by displacing a stylus above a digitizer. Task difficulty corresponded to racquet width. Half the participants (self-control condition) could choose the racquet…

Learners with Behavioural, Emotional and Social Difficulties' Experiences of Reintegration into Mainstream Education

ERIC Educational Resources Information Center

Pillay, Jace; Dunbar-Krige, Helen; Mostert, Jacques

2013-01-01

Behavioural, emotional and social difficulties (BESD) are a significant impediment to effective teaching and learning in England and Wales. Initiatives such as in-school Learning Support Units (LSUs) and off-site Pupil Referral Units (PRUs) aim to address BESD through short-term individualised learning programmes, followed by mandatory…

Opportunity-to-Learn Context-Based Tasks Provided by Mathematics Textbooks

ERIC Educational Resources Information Center

Wijaya, Ariyadi; van den Heuvel-Panhuizen, Marja; Doorman, Michiel

2015-01-01

Based on the findings of an error analysis revealing that Indonesian ninth- and tenth-graders had difficulties in solving context-based tasks, we investigated the opportunity-to-learn offered by Indonesian textbooks for solving context-based mathematics tasks and the relation of this opportunity-to-learn to students' difficulties in solving these…

Enabling Pupils with Learning Difficulties to Reflect on Their Own Thinking.

ERIC Educational Resources Information Center

Powell, Stuart D.; Makin, Michael

1994-01-01

Reports on a study of the impact of metacognition among 10 middle school-aged British students with learning difficulties. Finds that student awareness and subsequent control over thought processes were enhanced through self-reporting and self-appraisal. Examines this kind of reflection on enhanced learning capabilities and self-esteem. (CFR)

Analysis of Learning in the Case of a Teaching on Heat and Temperature.

ERIC Educational Resources Information Center

Tiberghien, Andree

In the domain of research on physics education, results on students' conceptions show difficulties in physics learning. This paper aims to propose theoretical elements to interpret such learning difficulties related to physics teaching in the case of heat and temperature. Sections in this paper include: (1) Introduction; (2) Epistemological…

Learning Computing Topics in Undergraduate Information Systems Courses: Managing Perceived Difficulty

ERIC Educational Resources Information Center

Wall, Jeffrey D.; Knapp, Janice

2014-01-01

Learning technical computing skills is increasingly important in our technology driven society. However, learning technical skills in information systems (IS) courses can be difficult. More than 20 percent of students in some technical courses may dropout or fail. Unfortunately, little is known about students' perceptions of the difficulty of…

Effects of Semantic Ambiguity Detection Training on Reading Comprehension Achievement of English Learners with Learning Difficulties

ERIC Educational Resources Information Center

Jozwik, Sara L.; Douglas, Karen H.

2016-01-01

This study examined how explicit instruction in semantic ambiguity detection affected the reading comprehension and metalinguistic awareness of five English learners (ELs) with learning difficulties (e.g., attention deficit/hyperactivity disorder, specific learning disability). A multiple probe across participants design (Gast & Ledford, 2010)…

Learning Difficulties of Diabetic Patients: A Survey of Educators.

ERIC Educational Resources Information Center

Bonnet, Caroline; Gagnayre, Remi; d'Ivernois, Jean-Francois

1998-01-01

Surveys 85 health care professionals on the learning difficulties of diabetic patients. Results show that educators find it easy to teach techniques: patients master procedures well and make few mistakes. In contrast, diabetic patients seem to have problems learning skills, such as insulin dose adjustment, that require complex problem-solving.…

EasyLexia 2.0: Redesigning Our Mobile Application for Children with Learning Difficulties

ERIC Educational Resources Information Center

Skiada, Roxani; Soroniati, Eva; Gardeli, Anna; Zissis, Dimitrios

2014-01-01

Dyslexia is one of the most common learning difficulties affecting approximately 15 to 20 per cent of the world's population. A large amount of research is currently being conducted in exploring the potential benefits of using Information & Communication Technologies as a learning platform for individuals and especially children with such…

Academic Attainment in Students with Dyslexia in Distance Education.

PubMed

Richardson, John T E

2015-11-01

This investigation studied attainment in students with dyslexia or other specific learning difficulties who were taking modules by distance learning with the Open University in 2012. Students with dyslexia or other specific learning difficulties who had no additional disabilities were just as likely as nondisabled students to complete their modules, but they were less likely to pass the modules that they had completed and less likely to obtain good grades on the modules that they had passed. Students with dyslexia or other specific learning difficulties who had additional disabilities were less likely to complete their modules, less likely to pass the modules that they had completed and less likely to obtain good grades on the modules that they had passed than were nondisabled students. Nevertheless, around 40% of students with dyslexia or other specific learning difficulties obtained good grades (i.e. those that would lead to a bachelor's degree with first-class or upper second-class honours). Copyright © 2015 John Wiley & Sons, Ltd.

Adaptive categorization of ART networks in robot behavior learning using game-theoretic formulation.

PubMed

Fung, Wai-keung; Liu, Yun-hui

2003-12-01

Adaptive Resonance Theory (ART) networks are employed in robot behavior learning. Two of the difficulties in online robot behavior learning, namely, (1) exponential memory increases with time, (2) difficulty for operators to specify learning tasks accuracy and control learning attention before learning. In order to remedy the aforementioned difficulties, an adaptive categorization mechanism is introduced in ART networks for perceptual and action patterns categorization in this paper. A game-theoretic formulation of adaptive categorization for ART networks is proposed for vigilance parameter adaptation for category size control on the categories formed. The proposed vigilance parameter update rule can help improving categorization performance in the aspect of category number stability and solve the problem of selecting initial vigilance parameter prior to pattern categorization in traditional ART networks. Behavior learning using physical robot is conducted to demonstrate the effectiveness of the proposed adaptive categorization mechanism in ART networks.

Soda Intake Is Directly Associated with Serum C-Reactive Protein Concentration in Mexican Women.

PubMed

Tamez, Martha; Monge, Adriana; López-Ridaura, Ruy; Fagherazzi, Guy; Rinaldi, Sabina; Ortiz-Panozo, Eduardo; Yunes, Elsa; Romieu, Isabelle; Lajous, Martin

2018-01-01

Soda intake is associated with an increased risk of cardiovascular disease. Consumption of diet sodas, often considered healthy alternatives to sodas, could also increase the likelihood of cardiovascular outcomes. This study aims to evaluate the relation between soda and diet soda and biomarkers of cardiovascular risk. We conducted a cross-sectional analysis among 825 Mexican women free of diabetes, cardiovascular disease, and cancer, and for whom serum concentrations of C-reactive protein (CRP), C-peptide, adiponectin, and leptin were available. Mean ± SD age was 45.9 ± 6.6 y, the majority of women were premenopausal (60.4%), and the prevalence of obesity was 35%. We estimated the adjusted percentage differences in biomarkers and 95% CIs by performing multiple linear regression models comparing categories of consumption for soda and diet soda adjusting for age, family history of heart disease, menopause, menopausal hormone therapy, socioeconomic status, region, smoking, physical activity, alcohol intake, and dietary patterns. In the entire study sample we observed a 50% higher serum CRP concentration in women in the highest soda intake quartile (median intake: 202.9 mL/d, IQR: 101.4, 304.3 mL/d) compared to those in the lowest (median intake: 11.8 mL/d, IQR: 0.0, 152.1 mL/d). After stratification by menopausal status, results remained significant only for premenopausal women. Premenopausal women in the highest quartile of soda intake had 56% higher CRP concentration relative to women in the lowest quartile. We observed no significant association with the other biomarkers. After further adjustment for body mass index, a potential mediator, results remained significant only for CRP. Diet soda consumption was not associated with any of the biomarkers. Consumption of soda was associated with adverse levels in a biomarker of inflammation and cardiovascular risk, serum CRP, in Mexican women. These results add to the accumulating evidence on soda and cardiovascular risk. More research is necessary to understand the potential impact of artificially sweetened sodas. © 2018 American Society for Nutrition. All rights reserved.

Influence of manual lymphatic drainage on health-related quality of life and symptoms of chronic venous insufficiency: a randomized controlled trial.

PubMed

dos Santos Crisóstomo, Rute Sofia; Costa, Daniela Sofia Albino; de Luz Belo Martins, Catarina; Fernandes, Tânia Isabel Russo; Armada-da-Silva, Paulo A

2015-02-01

To evaluate the efficacy of manual lymphatic drainage (MLD) in improving health-related quality of life (HRQOL), symptomatology, and physical status in patients with chronic venous insufficiency (CVI). Single-blind randomized controlled trial. Health community attendant service. Subjects with CVI (N=41) were randomly assigned to an experimental group (n=20; mean age, 54.6±11.3y) or control group (n=21; mean age, 46.8±11.1y). The experimental group completed 10 lower extremity MLD sessions over 4 weeks and 1 educational session. The control group only attended the educational session. Outcome measures were taken at baseline (t0), at the end of 4 weeks (t1), and after 2 months for follow-up (t2). HRQOL was assessed with the Chronic Venous Insufficiency Quality of Life Questionnaire-20, symptoms (fatigue, heaviness) were assessed with a visual analog scale, severity of the disease was assessed with the Venous Clinical Severity Score (VCSS) (total score, score for each item), leg volumetry was assessed with perimeters, and plantar/dorsiflexion strength and ankle range of motion (ROM) were assessed with dynamometry. A significant interaction group×time effect was found for pain on HRQOL (F2,78=3.507; P=.035; partial η2=.087), clinical severity (F2,78=5.231; P=.007; partial η2=.118), especially for venous edema (assessed with the VCSS), fatigue (F1.67,65.21=4.690; P=.012; partial η2=.107), and heaviness (F1.57,61.32=9.702; P=.001; partial η2=.199), with the experimental group improving from t0 to t1 and t0 to t2 in all of these outcomes. No effect of MLD treatment could be found for ankle muscle strength, ankle ROM, and leg volume. Short-term MLD treatment ameliorates CVI severity and related edema, symptoms, and pain HRQOL in patients with CVI. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Surface wave effect on the upper ocean in marine forecast

NASA Astrophysics Data System (ADS)

Wang, Guansuo; Qiao, Fangli; Xia, Changshui; Zhao, Chang

2015-04-01

An Operational Coupled Forecast System for the seas off China and adjacent (OCFS-C) is constructed based on the paralleled wave-circulation coupled model, which is tested with comprehensive experiments and operational since November 1st, 2007. The main feature of the system is that the wave-induced mixing is considered in circulation model. Daily analyses and three day forecasts of three-dimensional temperature, salinity, currents and wave height are produced. Coverage is global at 1/2 degreed resolution with nested models up to 1/24 degree resolution in China Sea. Daily remote sensing sea surface temperatures (SST) are taken to relax to an analytical product as hot restarting fields for OCFS-C by the Nudging techniques. Forecasting-data inter-comparisons are performed to measure the effectiveness of OCFS-C in predicting upper-ocean quantities including SST, mixed layer depth (MLD) and subsurface temperature. The variety of performance with lead time and real-time is discussed as well using the daily statistic results for SST between forecast and satellite data. Several buoy observations and many Argo profiles are used for this validation. Except the conventional statistical metrics, non-dimension skill scores (SS) is taken to estimate forecast skill. Model SST comparisons with more one year-long SST time series from 2 buoys given a large SS value (more than 0.90). And skill in predicting the seasonal variability of SST is confirmed. Model subsurface temperature comparisons with that from a lot of Argo profiles indicated that OCFS-C has low skill in predicting subsurface temperatures between 80m and 120m. Inter-comparisons of MLD reveal that MLD from model is shallower than that from Argo profiles by about 12m. QCFS-C is successful and steady in predicting MLD. The daily statistic results for SST between 1-d, 2-d and 3-d forecast and data is adopted to describe variability of Skill in predicting SST with lead time or real time. In a word QCFS-C shows reasonable accuracy over a series of studies designed to test ability to predict upper ocean conditions.

SU-F-J-138: An Extension of PCA-Based Respiratory Deformation Modeling Via Multi-Linear Decomposition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iliopoulos, AS; Sun, X; Pitsianis, N

Purpose: To address and lift the limited degree of freedom (DoF) of globally bilinear motion components such as those based on principal components analysis (PCA), for encoding and modeling volumetric deformation motion. Methods: We provide a systematic approach to obtaining a multi-linear decomposition (MLD) and associated motion model from deformation vector field (DVF) data. We had previously introduced MLD for capturing multi-way relationships between DVF variables, without being restricted by the bilinear component format of PCA-based models. PCA-based modeling is commonly used for encoding patient-specific deformation as per planning 4D-CT images, and aiding on-board motion estimation during radiotherapy. However, themore » bilinear space-time decomposition inherently limits the DoF of such models by the small number of respiratory phases. While this limit is not reached in model studies using analytical or digital phantoms with low-rank motion, it compromises modeling power in the presence of relative motion, asymmetries and hysteresis, etc, which are often observed in patient data. Specifically, a low-DoF model will spuriously couple incoherent motion components, compromising its adaptability to on-board deformation changes. By the multi-linear format of extracted motion components, MLD-based models can encode higher-DoF deformation structure. Results: We conduct mathematical and experimental comparisons between PCA- and MLD-based models. A set of temporally-sampled analytical trajectories provides a synthetic, high-rank DVF; trajectories correspond to respiratory and cardiac motion factors, including different relative frequencies and spatial variations. Additionally, a digital XCAT phantom is used to simulate a lung lesion deforming incoherently with respect to the body, which adheres to a simple respiratory trend. In both cases, coupling of incoherent motion components due to a low model DoF is clearly demonstrated. Conclusion: Multi-linear decomposition can enable decoupling of distinct motion factors in high-rank DVF measurements. This may improve motion model expressiveness and adaptability to on-board deformation, aiding model-based image reconstruction for target verification. NIH Grant No. R01-184173.« less

Association between absolute volumes of lung spared from low-dose irradiation and radiation-induced lung injury after intensity-modulated radiotherapy in lung cancer: a retrospective analysis.

PubMed

Chen, Jinmei; Hong, Jinsheng; Zou, Xi; Lv, Wenlong; Guo, Feibao; Hong, Hualan; Zhang, Weijian

2015-11-01

The aim of this study was to investigate the association between absolute volumes of lung spared from low-dose irradiation and radiation-induced lung injury (RILI) after intensity-modulated radiotherapy (IMRT) for lung cancer. The normal lung relative volumes receiving greater than 5, 10, 20 and 30 Gy (V5-30) mean lung dose (MLD), and absolute volumes spared from greater than 5, 10, 20 and 30 Gy (AVS5-30) for the bilateral and ipsilateral lungs of 83 patients were recorded. Any association of clinical factors and dose-volume parameters with Grade ≥2 RILI was analyzed. The median follow-up was 12.3 months; 18 (21.7%) cases of Grade 2 RILI, seven (8.4%) of Grade 3 and two (2.4%) of Grade 4 were observed. Univariate analysis revealed the located lobe of the primary tumor. V5, V10, V20, MLD of the ipsilateral lung, V5, V10, V20, V30 and MLD of the bilateral lung, and AVS5 and AVS10 of the ipsilateral lung were associated with Grade ≥2 RILI (P < 0.05). Multivariate analysis indicated AVS5 of the ipsilateral lung was prognostic for Grade ≥2 RILI (P = 0.010, OR = 0.272, 95% CI: 0.102-0.729). Receiver operating characteristic curves indicated Grade ≥2 RILI could be predicted using AVS5 of the ipsilateral lung (area under curve, 0.668; cutoff value, 564.9 cm(3); sensitivity, 60.7%; specificity, 70.4%). The incidence of Grade ≥2 RILI was significantly lower with AVS5 of the ipsilateral lung ≥564.9 cm(3) than with AVS5 < 564.9 cm(3) (P = 0.008). Low-dose irradiation relative volumes and MLD of the bilateral or ipsilateral lung were associated with Grade ≥2 RILI, and AVS5 of the ipsilateral lung was prognostic for Grade ≥2 RILI for lung cancer after IMRT. © The Author 2015. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

The use of depth interviewing with vulnerable subjects: lessons from a research study of parents with learning difficulties.

PubMed

Booth, T; Booth, W

1994-08-01

This paper explores the practicalities of using the technique of depth interviewing with people who have learning difficulties. The authors set out to provide other researchers with guidance in the use of the life story approach and to demonstrate its utility with this vulnerable and devalued group of informants. They conclude that depth interviewing can provide new knowledge not accessible through other methods of data collection, and offers a way of giving people with learning difficulties a voice in the making of their own history.

College students' understanding of stereochemistry: Difficulties in learning and critical junctures

NASA Astrophysics Data System (ADS)

Lyon, Gary Lester

Because stereochemistry is an important part of both high school and college chemistry curricula, a study of difficulties experienced by students in the learning of stereochemistry was undertaken in a one-semester college organic chemistry course. This study, conducted over the course of two semesters with more than two hundred students, utilized clinical interviews, concept maps, and student journals to identify these difficulties, which were then tabulated and categorized. Although student journals were not a productive source of information, the types of difficulties that emerged from the concept maps were compared and contrasted with those that emerged from the clinical interviews. Data from the concept maps were analyzed using Kendall's W, a nonparametric statistic that was deemed appropriate for determining concordance between individual concept maps. The correlation between values of Kendall's W for sets of concept maps and multiple choice questions designed to evaluate the content of these same maps was determined, with values of Pearson's r of .8093 (p = .051) and .7191 (p = .044) for the Fall, 1997 and Spring, 1998 semesters, respectively. These data were used to estimate the occurrence of critical junctures in the learning of stereochemistry, or points at which students must possess a certain framework of understanding of previous concepts in order to master new material (Trowbridge & Wandersee, 1994). One critical juncture was identified that occurred when the topics of enantiorners, absolute configuration, and inversion of configuration were introduced. Among the more important conclusions of this study to the learning of stereochemistry are the following. Both concept maps and interviews provided useful information regarding difficulties in the learning of stereochemistry; this information was complementary in some aspects and similar in others. Concept maps were useful in diagnosing difficulties in application of terms and definitions, whereas interviews were useful when seeking information about difficulties in the manipulation of chemical structures. Both concept maps and interviews were superior to student journals as tools to probe student difficulties in the learning of stereochemistry.

Psychomotor development and learning difficulties in preschool children with probable attention deficit hyperactivity disorder: An epidemiological study in Navarre and La Rioja.

PubMed

Marín-Méndez, J J; Borra-Ruiz, M C; Álvarez-Gómez, M J; Soutullo Esperón, C

2017-10-01

ADHD symptoms begin to appear at preschool age. ADHD may have a significant negative impact on academic performance. In Spain, there are no standardized tools for detecting ADHD at preschool age, nor is there data about the incidence of this disorder. To evaluate developmental factors and learning difficulties associated with probable ADHD and to assess the impact of ADHD in school performance. We conducted a population-based study with a stratified multistage proportional cluster sample design. We found significant differences between probable ADHD and parents' perception of difficulties in expressive language, comprehension, and fine motor skills, as well as in emotions, concentration, behaviour, and relationships. Around 34% of preschool children with probable ADHD showed global learning difficulties, mainly in patients with the inattentive type. According to the multivariate analysis, learning difficulties were significantly associated with both delayed psychomotor development during the first 3 years of life (OR: 5.57) as assessed by parents, and probable ADHD (OR: 2.34) CONCLUSIONS: There is a connection between probable ADHD in preschool children and parents' perception of difficulties in several dimensions of development and learning. Early detection of ADHD at preschool ages is necessary to start prompt and effective clinical and educational interventions. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Learning approaches and learning difficulties: a comparison of Indian and Nepali dental science students.

PubMed

Mayya, Shreemathi S; Rao, A Krishna; Ramnarayan, K

2002-11-01

This study explored the difference in learning approaches and difficulties of Nepali and Indian undergraduate students of dental science. A locally developed inventory was used to measure learning approach and learning difficulties. Data collected from 166 Indians and 69 Nepalis were compared. The scores on various scales of the inventory indicate that Nepalis are more fearful and less confident regarding examination and course completion and have significantly less positive perception about academic capability. Indian students scored significantly higher on motivation, interest, and deep processing. The language problem was significantly greater for Nepali students. Higher percentages of Nepalis experienced various academic and nonacademic problems. The study highlights the need to consider difference in learning approach among the students of health science courses that admit students from different academic, nonacademic, and cultural backgrounds.

Novel-word learning deficits in Mandarin-speaking preschool children with specific language impairments.

PubMed

Chen, Yuchun; Liu, Huei-Mei

2014-01-01

Children with SLI exhibit overall deficits in novel word learning compared to their age-matched peers. However, the manifestation of the word learning difficulty in SLI was not consistent across tasks and the factors affecting the learning performance were not yet determined. Our aim is to examine the extent of word learning difficulties in Mandarin-speaking preschool children with SLI, and to explore the potent influence of existing lexical knowledge on to the word learning process. Preschool children with SLI (n=37) and typical language development (n=33) were exposed to novel words for unfamiliar objects embedded in stories. Word learning tasks including the initial mapping and short-term repetitive learning were designed. Results revealed that Mandarin-speaking preschool children with SLI performed as well as their age-peers in the initial form-meaning mapping task. Their word learning difficulty was only evidently shown in the short-term repetitive learning task under a production demand, and their learning speed was slower than the control group. Children with SLI learned the novel words with a semantic head better in both the initial mapping and repetitive learning tasks. Moderate correlations between stand word learning performances and scores on standardized vocabulary were found after controlling for children's age and nonverbal IQ. The results suggested that the word learning difficulty in children with SLI occurred in the process of establishing a robust phonological representation at the beginning stage of word learning. Also, implicit compound knowledge is applied to aid word learning process for children with and without SLI. We also provide the empirical data to validate the relationship between preschool children's word learning performance and their existing receptive vocabulary ability. Copyright © 2013 Elsevier Ltd. All rights reserved.

Making the Jump: 'We Can Do a Good Job'. A Pack for Adults with Learning Difficulties Who Want To Work.

ERIC Educational Resources Information Center

Jacobsen, Yola

This document uses clear language and pictures to help adults with learning disabilities learn how other adults with learning difficulties have made the jump from courses and training into jobs and kept working. The following are among the topics discussed in Sections 1 through 9: (1) the objectives and activities of the Making the Jump project…

Gradual training reduces practice difficulty while preserving motor learning of a novel locomotor task.

PubMed

Sawers, Andrew; Hahn, Michael E

2013-08-01

Motor learning strategies that increase practice difficulty and the size of movement errors are thought to facilitate motor learning. In contrast to this, gradual training minimizes movement errors and reduces practice difficulty by incrementally introducing task requirements, yet remains as effective as sudden training and its large movement errors for learning novel reaching tasks. While attractive as a locomotor rehabilitation strategy, it remains unknown whether the efficacy of gradual training extends to learning locomotor tasks and their unique requirements. The influence of gradual vs. sudden training on learning a locomotor task, asymmetric split belt treadmill walking, was examined by assessing whole body sagittal plane kinematics during 24 hour retention and transfer performance following either gradual or sudden training. Despite less difficult and less specific practice for the gradual cohort on day 1, gradual training resulted in equivalent motor learning of the novel locomotor task as sudden training when assessed by retention and transfer a day later. This suggests that large movement errors and increased practice difficulty may not be necessary for learning novel locomotor tasks. Further, gradual training may present a viable locomotor rehabilitation strategy avoiding large movement errors that could limit or impair improvements in locomotor performance. Copyright © 2013 Elsevier B.V. All rights reserved.

Improving students' understanding of quantum mechanics

NASA Astrophysics Data System (ADS)

Zhu, Guangtian

2011-12-01

Learning physics is challenging at all levels. Students' difficulties in the introductory level physics courses have been widely studied and many instructional strategies have been developed to help students learn introductory physics. However, research shows that there is a large diversity in students' preparation and skills in the upper-level physics courses and it is necessary to provide scaffolding support to help students learn advanced physics. This thesis explores issues related to students' common difficulties in learning upper-level undergraduate quantum mechanics and how these difficulties can be reduced by research-based learning tutorials and peer instruction tools. We investigated students' difficulties in learning quantum mechanics by administering written tests and surveys to many classes and conducting individual interviews with a subset of students. Based on these investigations, we developed Quantum Interactive Learning Tutorials (QuILTs) and peer instruction tools to help students build a hierarchical knowledge structure of quantum mechanics through a guided approach. Preliminary assessments indicate that students' understanding of quantum mechanics is improved after using the research-based learning tools in the junior-senior level quantum mechanics courses. We also designed a standardized conceptual survey that can help instructors better probe students' understanding of quantum mechanics concepts in one spatial dimension. The validity and reliability of this quantum mechanics survey is discussed.

Math Anxiety and Math Ability in Early Primary School Years.

PubMed

Krinzinger, Helga; Kaufmann, Liane; Willmes, Klaus

2009-06-01

Mathematical learning disabilities (MLDs) are often associated with math anxiety, yet until now, very little is known about the causal relations between calculation ability and math anxiety during early primary school years. The main aim of this study was to longitudinally investigate the relationship between calculation ability, self-reported evaluation of mathematics, and math anxiety in 140 primary school children between the end of first grade and the middle of third grade. Structural equation modeling revealed a strong influence of calculation ability and math anxiety on the evaluation of mathematics but no effect of math anxiety on calculation ability or vice versa-contrasting with the frequent clinical reports of math anxiety even in very young MLD children. To summarize, our study is a first step toward a better understanding of the link between math anxiety and math performance in early primary school years performance during typical and atypical courses of development.

Math Anxiety and Math Ability in Early Primary School Years

PubMed Central

Krinzinger, Helga; Kaufmann, Liane; Willmes, Klaus

2010-01-01

Mathematical learning disabilities (MLDs) are often associated with math anxiety, yet until now, very little is known about the causal relations between calculation ability and math anxiety during early primary school years. The main aim of this study was to longitudinally investigate the relationship between calculation ability, self-reported evaluation of mathematics, and math anxiety in 140 primary school children between the end of first grade and the middle of third grade. Structural equation modeling revealed a strong influence of calculation ability and math anxiety on the evaluation of mathematics but no effect of math anxiety on calculation ability or vice versa—contrasting with the frequent clinical reports of math anxiety even in very young MLD children. To summarize, our study is a first step toward a better understanding of the link between math anxiety and math performance in early primary school years performance during typical and atypical courses of development. PMID:20401159

The Creation of Task-Based Differentiated Learning Materials for Students with Learning Difficulties and/or Disabilities.

ERIC Educational Resources Information Center

Barker, Trevor; Jones, Sara; Britton, Carol; Messer, David

This paper describes Horizon, a European-funded project designed to increase employment opportunities for students with disabilities or learning difficulties. The project established a working cafe/restaurant (Cafe Horizon) in East London staffed by students. Part of the project involved the creation of multimedia units linked directly to Level 1…

Morphing Images: A Potential Tool for Teaching Word Recognition to Children with Severe Learning Difficulties

ERIC Educational Resources Information Center

Sheehy, Kieron

2005-01-01

Children with severe learning difficulties who fail to begin word recognition can learn to recognise pictures and symbols relatively easily. However, finding an effective means of using pictures to teach word recognition has proved problematic. This research explores the use of morphing software to support the transition from picture to word…

Text Difficulty Affects Metacomprehension Accuracy and Knowledge Test Performance in Text Learning

ERIC Educational Resources Information Center

Vössing, J.; Stamov-Roßnagel, C.; Heinitz, K.

2017-01-01

Metacomprehension as reflected in judgements of one's learning is crucial for self-regulated study, yet their accuracy is often low. We investigated text difficulty as a constraint on metacomprehension accuracy in text learning. A total of 235 participants studied a 10-section expository text and afterwards took a knowledge test. They made…

Response to Intervention: Building the Capacity of Teachers to Serve Students with Learning Difficulties

ERIC Educational Resources Information Center

Richards, Catherine; Pavri, Shireen; Golez, Felipe; Canges, Rebecca; Murphy, Joanne

2007-01-01

In thirty years since federal special education law, PL 94-142 (1975), there has been much debate about how to best identify and serve students with learning disabilities and those at-risk for learning difficulties. This debate continues even after the most recent reauthorization of the Individuals with Disabilities Education Improvement Act…

Towards Motivation-Based Adaptation of Difficulty in E-Learning Programs

ERIC Educational Resources Information Center

Endler, Anke; Rey, Gunter Daniel; Butz, Martin V.

2012-01-01

The objective of this study was to investigate if an e-learning environment may use measurements of the user's current motivation to adapt the level of task difficulty for more effective learning. In the reported study, motivation-based adaptation was applied randomly to collect a wide range of data for different adaptations in a variety of…

Applying Cognitive Behavioural Methods to Retrain Children's Attributions for Success and Failure in Learning

ERIC Educational Resources Information Center

Toland, John; Boyle, Christopher

2008-01-01

This study involves the use of methods derived from cognitive behavioral therapy (CBT) to change the attributions for success and failure of school children with regard to learning. Children with learning difficulties and/or motivational and self-esteem difficulties (n = 29) were identified by their schools. The children then took part in twelve…

"Trying, Failing, Succeeding, and Trying Again and Again": Perspectives of Teachers of Pupils with Severe Profound Multiple Learning Difficulties

ERIC Educational Resources Information Center

Jones, Phyllis; Riley, Michael W.

2017-01-01

This article explores the perspectives of seven teachers in England who teach pupils with severe profound and multiple learning difficulties about their learning to teach this group of students. Teachers' views were captured through a combination of synchronous and asynchronous online communications. Four themes emerged from teachers' perspectives…

Spatial Working Memory and Arithmetic Deficits in Children with Nonverbal Learning Difficulties

ERIC Educational Resources Information Center

Mammarella, Irene Cristina; Lucangeli, Daniela; Cornoldi, Cesare

2010-01-01

Visuospatial working memory and its involvement in arithmetic were examined in two groups of 7- to 11-year-olds: one comprising children described by teachers as displaying symptoms of nonverbal learning difficulties (N = 21), the other a control group without learning disabilities (N = 21). The two groups were matched for verbal abilities, age,…

Mathematics Learning Difficulties in Primary Education: Teachers' Professional Knowledge and the Use of Commercially Available Learning Packages

ERIC Educational Resources Information Center

Van Steenbrugge, H.; Valcke, M.; Desoete, A.

2010-01-01

The present study builds on teachers' professional knowledge about mathematics learning difficulties. Based on the input of 918 primary school teachers, an attempt is made to develop an overview of difficult curriculum topics in primary school mathematics. The research approach builds on new conceptions about the professional identity of teachers…

Storytelling Supported by Technology: An Alternative for EFL Children with Learning Difficulties

ERIC Educational Resources Information Center

Lee, Sy-ying

2012-01-01

This action research aims to investigate how technology improves the conditions of storytelling to help enhance the learning attitude and motivation of EFL children with learning difficulty using power point designs and an online recording system--VoiceThread (http://voicethread.com/). The use of power point designs is to assure children of clear…

Learning Journeys: A Resource Handbook on Adult Learning and Mental Health.

ERIC Educational Resources Information Center

Mather, Joy; Atkinson, Sue

This document explains how tutors and managers in adult education programs across the United Kingdom can smooth the journeys of adults with mental health difficulties who are returning to learning. The handbook begins with suggestions for its use and case studies of two adult learners with mental health difficulties. Sections 1 through 4 discuss…

The Effect of Selected "Desirable Difficulties" on the Ability to Recall Anatomy Information

ERIC Educational Resources Information Center

Dobson, John L.; Linderholm, Tracy

2015-01-01

"Desirable difficulties" is a theory from cognitive science used to promote learning in a variety of contexts. The basic premise is that creating a cognitively challenging environment at the learning acquisition phase, by actively engaging learners in the retrieval of to-be-learned materials, promotes long-term retention. In this study,…

Getting the Gist: Relating Text Processing Research to Reading and Writing Instruction for Learning Disabled Secondary Students. Long Island University Transition Project Learning How to Learn: A High School/College Linkage Model to Expand Higher Educational Opportunities for Learning Disabled Students. Position Paper Series: Document No. 5.

ERIC Educational Resources Information Center

Seidenberg, Pearl L.

Many learning disabled secondary school students have difficulties with text organization in both subject area reading and expository writing. Problems may include difficulty in following the main ideas in text, recognizing the main text topics and their interrelationships, or recognizing the subordinate and superordinate ideas and examples.…

Neurological outcomes after hematopoietic stem cell transplantation for cerebral X-linked adrenoleukodystrophy, late onset metachromatic leukodystrophy and Hurler syndrome.

PubMed

Saute, Jonas Alex Morales; Souza, Carolina Fischinger Moura de; Poswar, Fabiano de Oliveira; Donis, Karina Carvalho; Campos, Lillian Gonçalves; Deyl, Adriana Vanessa Santini; Burin, Maira Graeff; Vargas, Carmen Regla; Matte, Ursula da Silveira; Giugliani, Roberto; Saraiva-Pereira, Maria Luiza; Vedolin, Leonardo Modesti; Gregianin, Lauro José; Jardim, Laura Bannach

2016-12-01

To describe survival and neurological outcomes after HSCT for these disorders. Seven CALD, 2 MLD and 2 MPS-IH patients underwent HSCT between 2007 and 2014. Neurological examinations, magnetic resonance imaging, molecular and biochemical studies were obtained at baseline and repeated when appropriated. Favorable outcomes were obtained with 4/5 related and 3/6 unrelated donors. Two patients died from procedure-related complications. Nine transplanted patients were alive after a median of 3.7 years: neurological stabilization was obtained in 5/6 CALD, 1/2 MLD, and one MPS-IH patient. Brain lesions of the MPS-IH patient were reduced four years after HSCT. Good outcomes were obtained when HSCT was performed before adulthood, early in the clinical course, and/or from a related donor.

Kinetics of the immune response to the (F1+V) vaccine in models of bubonic and pneumonic plague.

PubMed

Williamson, E D; Stagg, A J; Eley, S M; Taylor, R; Green, M; Jones, S M; Titball, R W

2007-01-22

Protection against aerosol challenge with > 300 MLD of Yersinia pestis was observed 7 days after a single immunisation of mice with the F1+V vaccine. At day 60, mice were protected against injected challenge (10(7)MLD) in a vaccine dose-related manner. Recall responses to rV in splenocytes ex vivo at day 98 correlated significantly (p<0.001) with the immunising dose-level of V antigen; no memory response or anti-V serum IgG was detected in killed whole cell vaccine (KWCV) recipients. This may explain the susceptibility of KWCV recipients to aerosol challenge and the enhanced protection conferred by the F1+V sub-unit vaccine, particularly since the anti-F1 responses induced by either vaccine were similarly IgG1-polarised.

18-year variability of ultraviolet radiation penetration in the mid-latitude coastal waters of the western boundary Pacific

NASA Astrophysics Data System (ADS)

Kuwahara, Victor S.; Nozaki, Sena; Nakano, Junji; Toda, Tatsuki; Kikuchi, Tomohiko; Taguchi, Satoru

2015-07-01

The 18-year time-series shows in situ ultraviolet radiation (UVR) and photosynthetically active radiation (PAR) diffuse attenuation coefficient Kd(λ) have recurrent seasonal variability of high/low attenuation during summer/winter months, respectively, dependent on variability in water column stratification and concentrations of bio-optical properties. The mid-latitude coastal survey station displayed significant seasonality of the mixed layer depth (MLD) between 12 and 82 m which modified the distribution of chlorophyll a (4.6-24.9 mg m-2) and absorption of colored dissolved organic matter [aCDOM(320 nm) 0.043-1.34 m-1]. The median Kd(320 nm) displayed significant seasonality at 0.19-0.74 m-1 (C.V. = 44.1%) and seasonal variability within the euphotic layer [Z10%(320 nm) = 7-20%]. High attenuation of UVR with relatively moderate attenuation of PAR was consistently observed during the summer months when increased concentrations of terrestrially derived CDOM coupled with a shallow MLD were present. The winter season showed the opposite of low UVR and PAR attenuation due to a relatively deeper MLD coupled with low concentrations of bio-optical properties. Although the long term Kd(λ) did not vary significantly during the time-series, analysis of the interannual variability suggests there are positive and negative phases following the Pacific Decadal Oscillation (PDO) vis-a-vis variability in bio-optical properties (p < 0.001).

Effects of Erythropoiesis-stimulating Agents on Intestinal Flora in Peritoneal Fibrosis.

PubMed

Bilici, Muammer; Oz, Ibrahim Ilker; Uygun Ilikhan, Sevil; Borazan, Ali

2017-05-01

This study aimed to investigate the effects of erythropoiesis-stimulating agents (ESAs) on intestinal flora in peritoneal fibrosis. Twenty-four Wistar albino rats were divided into 3 groups as the control group, which received 0.9% saline (3 mL/d) intraperitoneally; the chlorhexidine gluconate (CH) group, which received 3 mL/d injections of 0.1% CH intraperitoneally, and the ESA group, which received 3 mL/d injections of 0.1% CH intraperitoneally and epoetin beta (3 doses of 20 IU/kg/wk) subcutaneously. On the 21st day, the rats were sacrificed and the visceral peritoneum samples were obtained from left liver bowel. Blood samples were obtained from abdominal aorta and intestinal flora samples were obtained from transverse colon. Histopathologically, the CH, ESA, and control groups had peritoneal thickness of 135.4 ± 22.2 µm, 48.6 ± 12.8 µm, and 6.0 ± 2.3 µm, respectively. Escherichia coli was the predominant bacterium in the intestinal flora in the control group. Significant changes in microbial composition of intestinal flora towards Proteus species and Enterobacter species was seen among the groups (P < .001). There was no significant difference between the ESA and CH groups regarding the isolates from blood cultures. However, the bacterial isolates from cultures of intestinal flora among these groups were significantly different (P < .05). Erythropoiesis-stimulating agents change intestinal flora by a clinically significant amount in experimental peritoneal fibrosis. We consider that ESAs achieve this via regulating intestinal peristaltism.

Kinetics and thermodynamics of ethanol production by Saccharomyces cerevisiae MLD10 using molasses.

PubMed

Arshad, Muhammad; Ahmed, Sibtain; Zia, Muhammad Anjum; Rajoka, Muhammad Ibrahim

2014-03-01

In this study, we have used ultraviolet (UV) and γ-ray induction to get a catabolite repression resistant and thermotolerant mutant with enhanced ethanol production along with optimization of sugar concentration and temperature of fermentation. Classical mutagenesis in two consecutive cycles of UV- and γ-ray-induced mutations evolved one best catabolite-resistant and thermotolerant mutant Saccharomyces cerevisiae MLD10 which showed improved ethanol yield (0.48 ± 0.02 g g(-1)), theoretical yield (93 ± 3%), and extracellular invertase productivity (1,430 ± 50 IU l(-1) h(-1)), respectively, when fermenting 180 g sugars l(-1) in molasses medium at 43 °C in 300 m(3) working volume fermenter. Ethanol production was highly dependent on invertase production. Enthalpy (ΔH*) (32.27 kJ M(-1)) and entropy (ΔS*) (-202.88 J M(-1) K(-1)) values at 43 °C by the mutant MLD10 were significantly lower than those of β-glucosidase production by a thermophilic mutant derivative of Thermomyces lanuginosus. These results confirmed the enhanced production of ethanol and invertase by this mutant derivative. These studies proved that mutant was significantly improved for ethanol production and was thermostable in nature. Lower fermentation time for ethanol production and maintenance of ethanol production rates (3.1 g l(-1) h(-1)) at higher temperature (43 °C) by this mutant could decrease the overall cost of fermentation process and increase the quality of ethanol production.

Comparison of the antiviral potential among soluble forms of herpes simplex virus type-2 glycoprotein D receptors, herpes virus entry mediator A, nectin-1 and nectin-2, in transgenic mice.

PubMed

Fujimoto, Yoshikazu; Tomioka, Yukiko; Ozaki, Kinuyo; Takeda, Keiko; Suyama, Haruka; Yamamoto, Sayo; Takakuwa, Hiroki; Morimatsu, Masami; Uede, Toshimitsu; Ono, Etsuro

2017-07-01

Herpesvirus entry mediator A (HVEM), nectin-1 and nectin-2 are cellular receptors of glycoprotein D (gD) of herpes simplex virus type-2 (HSV-2). It has been shown that soluble forms of HSV gD receptors have the antiviral potential in cultured cells and transgenic mice. Here, to compare antiviral potential of soluble forms of HVEM, nectin-1 and nectin-2 against HSV-2 infections in vivo, transgenic mice expressing fusion proteins consisting of the entire ectodomain of HVEM, nectin-1 or nectin-2 and the Fc portion of human IgG (HVEMIg, nectin-1Ig and nectin-2Ig, respectively) were intraperitoneally infected with HSV-2. In the infection with 3 MLD50 (50 % mouse lethal dose), effective resistance was not observed in transgenic mice expressing nectin-2Ig. In a transgenic mouse line with high expression of nectin-1Ig, significant protection from the infection with 30 and 300 MLD50 was observed (survival rate of 100 and 71 %, respectively). On the other hand, transgenic mice expressing HVEMIg showed a complete resistance to the lethal infection even with 300 MLD50 (survival rate of 100 %). These results demonstrated that HVEMIg could exert effective antiviral activities against HSV-2 infections in vivo as compared with other soluble forms of HSV gD receptors.

Seasonal surface circulation, temperature, and salinity in Prince William Sound, Alaska

NASA Astrophysics Data System (ADS)

Musgrave, David L.; Halverson, Mark J.; Scott Pegau, W.

2013-02-01

Salinity, temperature, and depth profiles from 1973 to 2010 were used to construct a seasonal climatology of surface temperature, surface salinity, mixed layer depth (MLD), potential energy of mixing, and surface geostrophic circulation in Prince William Sound (PWS) and the adjacent Gulf of Alaska. Surface salinity is greatest in winter and least in summer due to the influence of increased freshwater runoff in summer. It is generally lowest in the northwest and highest in the Gulf of Alaska. The surface temperature is lowest in the winter and highest in the summer when surface heating is greatest, with little spatial variability across the Sound. The MLD is deepest in winter (9-27 m) and shallowest in summer (4-5 m). The work by winds was estimated from meteorological buoy data in central PWS and compared to the potential energy of mixing of the upper water column. The potential depth to which winds mix the upper water column was generally consistent with the MLD. The surface geostrophic circulation in the central Sound has: a southerly flow in the western central Sound in the winter; a closed, weak anticyclonic cell in spring; a closed, cyclonic cell in the summer; an open, cyclonic circulation in the fall. In the western passages, a southerly flow occurs in spring, summer, and fall. These results have important implications for oil spill response in PWS, the use of oil dispersants, and for comparison to numerical studies.

To Find a Better Dosimetric Parameter in the Predicting of Radiation-Induced Lung Toxicity Individually: Ventilation, Perfusion or CT based.

PubMed

Xiao, Lin-Lin; Yang, Guoren; Chen, Jinhu; Wang, Xiaohui; Wu, Qingwei; Huo, Zongwei; Yu, Qingxi; Yu, Jinming; Yuan, Shuanghu

2017-03-15

This study aimed to find a better dosimetric parameter in predicting of radiation-induced lung toxicity (RILT) in patients with non-small cell lung cancer (NSCLC) individually: ventilation(V), perfusion (Q) or computerized tomography (CT) based. V/Q single-photon emission computerized tomography (SPECT) was performed within 1 week prior to radiotherapy (RT). All V/Q imaging data was integrated into RT planning system, generating functional parameters based on V/Q SPECT. Fifty-seven NSCLC patients were enrolled in this prospective study. Fifteen (26.3%) patients underwent grade ≥2 RILT, the remaining forty-two (73.7%) patients didn't. Q-MLD, Q-V20, V-MLD, V-V20 of functional parameters correlated more significantly with the occurrence of RILT compared to V20, MLD of anatomical parameters (r = 0.630; r = 0.644; r = 0.617; r = 0.651 vs. r = 0.424; r = 0.520 p < 0.05, respectively). In patients with chronic obstructive pulmonary diseases (COPD), V functional parameters reflected significant advantage in predicting RILT; while in patients without COPD, Q functional parameters reflected significant advantage. Analogous results were existed in fractimal analysis of global pulmonary function test (PFT). In patients with central-type NSCLC, V parameters were better than Q parameters; while in patients with peripheral-type NSCLC, the results were inverse. Therefore, this study demonstrated that choosing a suitable dosimetric parameter individually can help us predict RILT accurately.

Effect of Physical Methods of Lymphatic Drainage on Postexercise Recovery of Mixed Martial Arts Athletes.

PubMed

Zebrowska, Aleksandra; Trybulski, Robert; Roczniok, Robert; Marcol, Wieslaw

2017-08-16

Physical methods are reported to be important for accelerating skeletal muscle regeneration, decreasing muscle soreness, and shortening of the recovery time. The aim of the study was to assess the effect of the physical methods of lymphatic drainage (PMLD) such as manual lymphatic drainage (MLD), the Bodyflow (BF) therapy, and lymphatic drainage by deep oscillation (DO) on postexercise regeneration of the forearm muscles of mixed martial arts (MMA) athletes. Eighty MMA athletes aged 27.5 ± 6.4 years were allocated to 4 groups: MLD, the BF device, DO therapy, and the control group. Blood flow velocity in the cephalic vein was measured with the ultrasound Doppler velocity meter. Maximal strength of the forearm muscles (Fmax), muscle tissue tension, pain threshold, blood lactate concentration (LA), and activity of creatine kinase were measured in all groups at rest, after the muscle fatigue test (post-ex) and then 20 minutes, 24, and 48 hours after the application of PMLD. The muscle fatigue test reduced Fmax in all subjects, but in the groups receiving MLD, DO, and BF significantly higher Fmax was observed at recovery compared with post-ex values. The application of MDL reduced the postexercise blood LA and postexercise muscle tension. The lymphatic drainage methods, whether manual or using electro-stimulation and DO, improve postexercise regeneration of the forearm muscles of MMA athletes. The methods can be an important element of therapeutic management focused on optimizing training effects and reducing the risk of injuries of the combat sports athletes.

Difficulty in learning similar-sounding words: a developmental stage or a general property of learning?

PubMed Central

Pajak, Bozena; Creel, Sarah C.; Levy, Roger

2016-01-01

How are languages learned, and to what extent are learning mechanisms similar in infant native-language (L1) and adult second-language (L2) acquisition? In terms of vocabulary acquisition, we know from the infant literature that the ability to discriminate similar-sounding words at a particular age does not guarantee successful word-meaning mapping at that age (Stager & Werker, 1997). However, it is unclear whether this difficulty arises from developmental limitations of young infants (e.g., poorer working memory) or whether it is an intrinsic part of the initial word learning, L1 and L2 alike. Here we show that adults of particular L1 backgrounds—just like young infants—have difficulty learning similar-sounding L2 words that they can nevertheless discriminate perceptually. This suggests that the early stages of word learning, whether L1 or L2, intrinsically involve difficulty in mapping similar-sounding words onto referents. We argue that this is due to an interaction between two main factors: (1) memory limitations that pose particular challenges for highly similar-sounding words, and (2) uncertainty regarding the language's phonetic categories, as these are being learned concurrently with words. Overall, our results show that vocabulary acquisition in infancy and in adulthood share more similarities than previously thought, thus supporting the existence of common learning mechanisms that operate throughout the lifespan. PMID:26962959

Socioeconomic variation, number competence, and mathematics learning difficulties in young children.

PubMed

Jordan, Nancy C; Levine, Susan C

2009-01-01

As a group, children from disadvantaged, low-income families perform substantially worse in mathematics than their counterparts from higher-income families. Minority children are disproportionately represented in low-income populations, resulting in significant racial and social-class disparities in mathematics learning linked to diminished learning opportunities. The consequences of poor mathematics achievement are serious for daily functioning and for career advancement. This article provides an overview of children's mathematics difficulties in relation to socioeconomic status (SES). We review foundations for early mathematics learning and key characteristics of mathematics learning difficulties. A particular focus is the delays or deficiencies in number competencies exhibited by low-income children entering school. Weaknesses in number competence can be reliably identified in early childhood, and there is good evidence that most children have the capacity to develop number competence that lays the foundation for later learning.

Learning Self-Evaluation: Challenges for Students.

ERIC Educational Resources Information Center

MacGregor, Jean

1993-01-01

Self-evaluation is unfamiliar to most college students. Teachers can use varied approaches to support students in overcoming unfamiliarity with self-evaluation, lack of confidence in describing learning, writing difficulties, evaluation difficulties, discomfort discussing academic problems, cultural bias against self-evaluation, emotional…

Helping children with reading difficulties: some things we have learned so far

NASA Astrophysics Data System (ADS)

McArthur, Genevieve; Castles, Anne

2017-03-01

A substantial proportion of children struggle to learn to read. This not only impairs their academic achievement, but increases their risk of social, emotional, and mental health problems. In order to help these children, reading scientists have worked hard for over a century to better understand the nature of reading difficulties and the people who have them. The aim of this perspective is to outline some of the things that we have learned so far, and to provide a framework for considering the causes of reading difficulties and the most effective ways to treat them.

The Impact of Learning Difficulties and Socioemotional and Behavioural Problems on Transition to Postsecondary Education or Work Life in Finland: A Five-Year Follow-Up Study

ERIC Educational Resources Information Center

Hakkarainen, Airi M.; Holopainen, Leena K.; Savolainen, Hannu K.

2016-01-01

Learning difficulties have been found to dilute the possibilities that young adults have in their educational careers. However, during the last few decades, education has become increasingly important for employment and overall life satisfaction. In the present study, we were interested in the effects of mathematical and reading difficulties and…

Learning in the Learner's Perspective. III. Level of Difficulty Seen as a Relationship Between the Reader and the Text. No. 78.

ERIC Educational Resources Information Center

Marton, Ference; Saljo, Roger

Structural reading difficulty of argumentative prose (text with an underlying message or superordinate principle), is related to the reader's approach to reading and learning. Ninety Swedish teenagers and adults with varying levels of formal education, were divided into three groups, based on their own descriptions of reading and learning: deep…

Evaluation of an Innovative Programme for Training Teachers of Children with Learning and Behavioural Difficulties in New Zealand

ERIC Educational Resources Information Center

Pilgrim, Marcia; Hornby, Garry; Everatt, John; Macfarlane, Angus

2017-01-01

This article reports the views of recent graduates of a competency based, blended learning teacher education programme for specialist resource teachers of children with learning and behaviour difficulties in New Zealand. Identifying and developing the competencies needed by teachers in the field of special needs education is important in ensuring…

Movement and Learning in the Early Years: Supporting Dyspraxia (DCD) and Other Difficulties

ERIC Educational Resources Information Center

Macintrye, Christine; McVitty, Kim

2004-01-01

This book is written to support parents and practitioners who wish to understand movement and how it contributes to all aspects of learning--intellectual, social and emotional, as well as the movement/motor aspect itself. Moreover, as there is a huge increase in the number of children with movement learning difficulties (Keen, 2001), that is…

Investigating Cognitive Task Difficulties and Expert Skills in E-Learning Storyboards Using a Cognitive Task Analysis Technique

ERIC Educational Resources Information Center

Yusoff, Nor'ain Mohd; Salim, Siti Salwah

2012-01-01

E-learning storyboards have been a useful approach in distance learning development to support interaction between instructional designers and subject-matter experts. Current works show that researchers are focusing on different approaches for use in storyboards, and there is less emphasis on the effect of design and process difficulties faced by…

Treating the Whole Person: A Counseling, Psychology and Support Model for Learners with Learning Difficulty and Disabilities

ERIC Educational Resources Information Center

Lee, Larry

2014-01-01

Concerned about traditional practice that attempted to manage the challenging behavior of learners with learning difficulty and disabilities (LLDD) in learning and social environments, I questioned the extent to which they could manage themselves. From 265 students, 15 males, median age of 19, were invited to participate in 12 weekly one-hour…

The Role of Sentence Recall in Reading and Language Skills of Children with Learning Difficulties

ERIC Educational Resources Information Center

Alloway, Tracy Packiam; Gathercole, Susan Elizabeth

2005-01-01

The present study explores the relationship between sentence recall and reading and language skills in a group of 7--11-year-old children with learning difficulties. While recent studies have found that performance on sentence recall tasks plays a role in learning, it is possible that this contribution is a reflection of shared resources with…

On the Roots of Difficulties in Learning about Cell Division: Process-Based Analysis of Students' Conceptual Development in Teaching Experiments

ERIC Educational Resources Information Center

Riemeier, Tanja; Gropengiesser, Harald

2008-01-01

Empirical investigations on students' conceptions of cell biology indicate major misunderstandings of scientific concepts even after thorough teaching. Therefore, the main aim of our research project was to investigate students' difficulties in learning this topic and to study the impact of learning activities on students' conceptions. Using the…

9 CFR 113.110 - Clostridium Botulinum Type C Bacterin-Toxoid.

Code of Federal Regulations, 2011 CFR

2011-01-01

... challenged intraperitoneally with botulinum Type C toxin which has been titrated in mice to provide for a 104.0 mouse MLD dose. The titration technique shall include inoculation of the mice intraperitoneally...

Investigation Of Student Learning In Thermodynamics And Implications For Instruction In Chemistry And Engineering

NASA Astrophysics Data System (ADS)

Meltzer, David E.

2007-01-01

As part of an investigation into student learning of thermodynamics, we have probed the reasoning of students enrolled in introductory and advanced courses in both physics and chemistry. A particular focus of this work has been put on the learning difficulties encountered by physics, chemistry, and engineering students enrolled in an upper-level thermal physics course that included many topics also covered in physical chemistry courses. We have explored the evolution of students' understanding as they progressed from the introductory course through more advanced courses. Through this investigation we have gained insights into students' learning difficulties in thermodynamics at various levels. Our experience in addressing these learning difficulties may provide insights into analogous pedagogical issues in upper-level courses in both engineering and chemistry which focus on the theory and applications of thermodynamics.

The interface between spoken and written language: developmental disorders.

PubMed

Hulme, Charles; Snowling, Margaret J

2014-01-01

We review current knowledge about reading development and the origins of difficulties in learning to read. We distinguish between the processes involved in learning to decode print, and the processes involved in reading for meaning (reading comprehension). At a cognitive level, difficulties in learning to read appear to be predominantly caused by deficits in underlying oral language skills. The development of decoding skills appears to depend critically upon phonological language skills, and variations in phoneme awareness, letter-sound knowledge and rapid automatized naming each appear to be causally related to problems in learning to read. Reading comprehension difficulties in contrast appear to be critically dependent on a range of oral language comprehension skills (including vocabulary knowledge and grammatical, morphological and pragmatic skills).

Reading disorders and dyslexia.

PubMed

Hulme, Charles; Snowling, Margaret J

2016-12-01

We review current knowledge about the nature of reading development and disorders, distinguishing between the processes involved in learning to decode print, and the processes involved in reading comprehension. Children with decoding difficulties/dyslexia experience deficits in phoneme awareness, letter-sound knowledge and rapid automatized naming in the preschool years and beyond. These phonological/language difficulties appear to be proximal causes of the problems in learning to decode print in dyslexia. We review data from a prospective study of children at high risk of dyslexia to show that being at family risk of dyslexia is a primary risk factor for poor reading and children with persistent language difficulties at school entry are more likely to develop reading problems. Early oral language difficulties are strong predictors of later difficulties in reading comprehension. There are two distinct forms of reading disorder in children: dyslexia (a difficulty in learning to translate print into speech) and reading comprehension impairment. Both forms of reading problem appear to be predominantly caused by deficits in underlying oral language skills. Implications for screening and for the delivery of robust interventions for language and reading are discussed.

The nature and extent of aggressive behaviour amongst people with learning difficulties (mental handicap) in a single health district.

PubMed

Harris, P

1993-06-01

This paper describes the method and results of a survey of aggressive behaviour amongst people with learning difficulties. The study was confined to a single health district in the South Western Region of the UK with a general population of about 370,000. At the time of the survey, the Mental Handicap Register for the district recorded 1,362 people as having a learning difficulty. The overall prevalence of aggressive behaviour amongst people with learning difficulties for whom base population data was available was 17.6%. The lowest rate was identified amongst day facilities (9.7%) and the highest in hospitals within the district (38.2%). The prevalence rate amongst those attending schools for children with severe learning difficulties was 12.6%. Proportionately more males than females were reported to present problems of aggressive behaviour. The gender difference appeared to be largely accounted for by the disproportionate number of men identified within day facilities. There was no significant evidence of an association between the person's gender and the presence aggressive behaviour within schools or hospitals. The results indicated that, although physical and verbal aggression were the most frequently reported behaviours, many of the sample were also said to engage in other forms of challenging behaviour, particularly self-injurious, ritualistic, stereotypical and withdrawn behaviour. The risk of a serious or very serious injury to another person was very low; 0.7% or six people with learning difficulties from the district were reported to be currently presenting such a risk. Similarly, only 2% of the base population (n = 18) were reported to be extremely difficult to manage. The implications of the findings are discussed.

Involving users with learning difficulties in health improvement: lessons from inclusive learning disability research.

PubMed

Walmsley, Jan

2004-03-01

In this paper the author considers the lessons to be drawn from what is termed "inclusive" learning disability research for user involvement around health improvement. Inclusive learning disability research refers to research where people with learning difficulties (intellectual disability) are involved as active participants, as opposed to passive subjects. There is by now a considerable body of such research, developed over the past 25 years. From the review, the author draws attention to areas which can inform practice in involvement of users in a way that adds value.

The Effect of Self-Regulated and Experimenter-Imposed Practice Schedules on Motor Learning for Tasks of Varying Difficulty

ERIC Educational Resources Information Center

Keetch, Katherine M.; Lee, Timothy D.

2007-01-01

Research suggests that allowing individuals to control their own practice schedule has a positive effect on motor learning. In this experiment we examined the effect of task difficulty and self-regulated practice strategies on motor learning. The task was to move a mouse-operated cursor through pattern arrays that differed in two levels of…

Differentiated Curriculum Design: Responding to the Individual and Group Needs of Students with Learning Difficulties with Self-Regulated Learning Strategies

ERIC Educational Resources Information Center

Pui, Winnie Sin Wai

2016-01-01

The purpose of this study was to explore special educational curriculum design at senior secondary school level and whether this helps to enhance the academic attainment and self-confidence of students with learning difficulties. An in-depth discussion focuses on lesson planning for the individual needs and group needs of students by…

Obstaculos al aprendizaje--obstaculos a la ensenanza en contextos (Barriers to Learning--Barriers to Teaching in Multicultural Contexts). Papers on Teacher Training and Multicultural/Intercultural Education 25.

ERIC Educational Resources Information Center

Gagliardi, Raul

This study focused on identifying learning difficulties with a view to incorporating both understanding of those difficulties and methods for minimizing or neutralizing them in multicultural classroom settings. Discussion gives guidelines for teachers to use in analyzing student concepts and approaches to learning, particularly in the…

Children's Attitudes towards ADHD, Depression and Learning Disabilities

ERIC Educational Resources Information Center

Bellanca, Faye Francesca; Pote, Helen

2013-01-01

Attention deficit hyperactivity disorder (ADHD), depression and general learning disabilities (LD) are common difficulties for British primary school children. It has been found that characteristics associated with these difficulties can result in negative attitudes and stigma from other children, causing problems with peer relationships.…

Hybrid inorganic–organic superlattice structures with atomic layer deposition/molecular layer deposition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tynell, Tommi; Yamauchi, Hisao; Karppinen, Maarit, E-mail: maarit.karppinen@aalto.fi

2014-01-15

A combination of the atomic layer deposition (ALD) and molecular layer deposition (MLD) techniques is successfully employed to fabricate thin films incorporating superlattice structures that consist of single layers of organic molecules between thicker layers of ZnO. Diethyl zinc and water are used as precursors for the deposition of ZnO by ALD, while three different organic precursors are investigated for the MLD part: hydroquinone, 4-aminophenol and 4,4′-oxydianiline. The successful superlattice formation with all the organic precursors is verified through x-ray reflectivity studies. The effects of the interspersed organic layers/superlattice structure on the electrical and thermoelectric properties of ZnO are investigatedmore » through resistivity and Seebeck coefficient measurements at room temperature. The results suggest an increase in carrier concentration for small concentrations of organic layers, while higher concentrations seem to lead to rather large reductions in carrier concentration.« less

Meta-Analysis of Fluid Intelligence Tests of Children from the Chinese Mainland with Learning Difficulties

PubMed Central

Tong, Fang; Fu, Tong

2013-01-01

Objective To evaluate the differences in fluid intelligence tests between normal children and children with learning difficulties in China. Method PubMed, MD Consult, and other Chinese Journal Database were searched from their establishment to November 2012. After finding comparative studies of Raven measurements of normal children and children with learning difficulties, full Intelligent Quotation (FIQ) values and the original values of the sub-measurement were extracted. The corresponding effect model was selected based on the results of heterogeneity and parallel sub-group analysis was performed. Results Twelve documents were included in the meta-analysis, and the studies were all performed in mainland of China. Among these, two studies were performed at child health clinics, the other ten sites were schools and control children were schoolmates or classmates. FIQ was evaluated using a random effects model. WMD was −13.18 (95% CI: −16.50–−9.85). Children with learning difficulties showed significantly lower FIQ scores than controls (P<0.00001); Type of learning difficulty and gender differences were evaluated using a fixed-effects model (I2 = 0%). The sites and purposes of the studies evaluated here were taken into account, but the reasons of heterogeneity could not be eliminated; The sum IQ of all the subgroups showed considerable heterogeneity (I2 = 76.5%). The sub-measurement score of document A showed moderate heterogeneity among all documents, and AB, B, and E showed considerable heterogeneity, which was used in a random effect model. Individuals with learning difficulties showed heterogeneity as well. There was a moderate delay in the first three items (−0.5 to −0.9), and a much more pronounced delay in the latter three items (−1.4 to −1.6). Conclusion In the Chinese mainland, the level of fluid intelligence of children with learning difficulties was lower than that of normal children. Delayed development in sub-items of C, D, and E was more obvious. PMID:24236016

[Integral assessment of learning subjects difficulties].

PubMed

Grebniak, N P; Shchudro, S A

2010-01-01

The integral criterion for subject difficulties in senior classes is substantiated in terms of progress in studies, variation coefficient, and subjective and expert appraisals of the difficulty of subjects. The compiled regression models adequately determine the difficulty of academic subjects. According to the root-mean-square deviation, all subjects were found to have 3 degrees of difficulty.

Poor Executive Functions among Children with Moderate-into-Severe Asthma: Evidence from WCST Performance.

PubMed

Taha, Haitham

2017-01-01

Executive functions (EFs) measures of 27 asthmatic children, with general learning difficulties, were tested by using the Wisconsin card sorting test (WCST), and were compared to the performances of 30 non-asthmatic children with general learning difficulties. The results revealed that the asthmatic group has poor performance through all the WCST psychometric parameters and especially the perseverative errors one. The results were discussed in light of the postulation that poor EFs could be associated with the learning difficulties of asthmatic children. Neurophysiological framework has been suggested to explain the etiology of poor EFs among children with moderate into severe asthma.

Specific Learning Difficulties--What Teachers Need to Know

ERIC Educational Resources Information Center

Hudson, Diana

2015-01-01

This book clearly explains what Specific Learning Difficulties (SpLD) are, and describes the symptoms of conditions most commonly encountered in the mainstream classroom: dyslexia, dyspraxia, dyscalculia, dysgraphia, Autism Spectrum Disorder, ADHD, and OCD. The author provides an overview of the strengths and weaknesses commonly associated with…

In Physics Education, Perception Matters

ERIC Educational Resources Information Center

Sattizahn, Jason R.; Lyons, Daniel J.; Kontra, Carly; Fischer, Susan M.; Beilock, Sian L.

2015-01-01

Student difficulties in science learning are frequently attributed to misconceptions about scientific concepts. We argue that domain-general perceptual processes may also influence students' ability to learn and demonstrate mastery of difficult science concepts. Using the concept of center of gravity (CoG), we show how student difficulty in…

Difficulties in Initial Algebra Learning in Indonesia

ERIC Educational Resources Information Center

Jupri, Al; Drijvers, Paul; van den Heuvel-Panhuizen, Marja

2014-01-01

Within mathematics curricula, algebra has been widely recognized as one of the most difficult topics, which leads to learning difficulties worldwide. In Indonesia, algebra performance is an important issue. In the Trends in International Mathematics and Science Study (TIMSS) 2007, Indonesian students' achievement in the algebra domain was…

Characterisation of Sleep Problems in Children with Williams Syndrome

ERIC Educational Resources Information Center

Annaz, Dagmara; Hill, Catherine M.; Ashworth, Anna; Holley, Simone; Karmiloff-Smith, Annette

2011-01-01

Sleep is critical to optimal daytime functioning, learning and general health. In children with established developmental disorders sleep difficulties may compound existing learning difficulties. The purpose of the present study was to evaluate the prevalence and syndrome specificity of sleep problems in Williams syndrome (WS), a…

Learning difficulties: a retrospective study of their co morbidity and continuity as indicators of adult criminal behaviour in 18-70-year-old prisoners.

PubMed

Zakopoulou, Victoria; Pashou, Theodora; Tzavelas, Panagiotis; Christodoulides, Pavlos; Anna, Milona; Iliana, Kolotoura

2013-11-01

The development of learning difficulties is associated with problems in external (executive) and extensive behaviour in a co-occurrence with psycho-emotional problems beginning from pre-school, school age, and adolescence up to adulthood. Through the current survey, we aim to emphasise the early role of learning difficulties during the school age and adolescence of prisoners and their effects on the onset of offending behaviours in adulthood, such as criminal behaviour. Altogether, we studied 117 Greek adult prisoners from 18 to 70 years old who were accused of different types or degrees of offences. Through statistical analyses, the following factors were observed with high statistical significance as early indicators of criminal behaviour in the adult lives of the prisoners: (i) learning difficulties, (ii) family problems, (iii) behaviour disorders, (iv) developmental disorders, and (v) psycho-emotional disorders. As a result, the learning difficulties were assumed to be the most decisive factor in the developmental progression of prisoners because they manifested early in the prisoners' lives, weakened the prisoners to be competitive and robust, provoked a bad self-image and low self-esteem, and, in the frame of a weak or negative family and educational environment, they accompanied antisocial behaviour and psycho-emotional disorders even from adolescence, which continued into adulthood. Copyright © 2013 Elsevier Ltd. All rights reserved.

Atomic and molecular layer deposition for surface modification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vähä-Nissi, Mika, E-mail: mika.vaha-nissi@vtt.fi; Sievänen, Jenni; Salo, Erkki

2014-06-01

Atomic and molecular layer deposition (ALD and MLD, respectively) techniques are based on repeated cycles of gas–solid surface reactions. A partial monolayer of atoms or molecules is deposited to the surface during a single deposition cycle, enabling tailored film composition in principle down to molecular resolution on ideal surfaces. Typically ALD/MLD has been used for applications where uniform and pinhole free thin film is a necessity even on 3D surfaces. However, thin – even non-uniform – atomic and molecular deposited layers can also be used to tailor the surface characteristics of different non-ideal substrates. For example, print quality of inkjetmore » printing on polymer films and penetration of water into porous nonwovens can be adjusted with low-temperature deposited metal oxide. In addition, adhesion of extrusion coated biopolymer to inorganic oxides can be improved with a hybrid layer based on lactic acid. - Graphical abstract: Print quality of a polylactide film surface modified with atomic layer deposition prior to inkjet printing (360 dpi) with an aqueous ink. Number of printed dots illustrated as a function of 0, 5, 15 and 25 deposition cycles of trimethylaluminum and water. - Highlights: • ALD/MLD can be used to adjust surface characteristics of films and fiber materials. • Hydrophobicity after few deposition cycles of Al{sub 2}O{sub 3} due to e.g. complex formation. • Same effect on cellulosic fabrics observed with low temperature deposited TiO{sub 2}. • Different film growth and oxidation potential with different precursors. • Hybrid layer on inorganic layer can be used to improve adhesion of polymer melt.« less

On-line determination of pork color and intramuscular fat by computer vision

NASA Astrophysics Data System (ADS)

Liao, Yi-Tao; Fan, Yu-Xia; Wu, Xue-Qian; Xie, Li-juan; Cheng, Fang

2010-04-01

In this study, the application potential of computer vision in on-line determination of CIE L*a*b* and content of intramuscular fat (IMF) of pork was evaluated. Images of pork chop from 211 pig carcasses were captured while samples were on a conveyor belt at the speed of 0.25 m•s-1 to simulate the on-line environment. CIE L*a*b* and IMF content were measured with colorimeter and chemical extractor as reference. The KSW algorithm combined with region selection was employed in eliminating the surrounding fat of longissimus dorsi muscle (MLD). RGB values of the pork were counted and five methods were applied for transforming RGB values to CIE L*a*b* values. The region growing algorithm with multiple seed points was applied to mask out the IMF pixels within the intensity corrected images. The performances of the proposed algorithms were verified by comparing the measured reference values and the quality characteristics obtained by image processing. MLD region of six samples could not be identified using the KSW algorithm. Intensity nonuniformity of pork surface in the image can be eliminated efficiently, and IMF region of three corrected images failed to be extracted. Given considerable variety of color and complexity of the pork surface, CIE L*, a* and b* color of MLD could be predicted with correlation coefficients of 0.84, 0.54 and 0.47 respectively, and IMF content could be determined with a correlation coefficient more than 0.70. The study demonstrated that it is feasible to evaluate CIE L*a*b* values and IMF content on-line using computer vision.

Importance of interaction between nerve growth factor and α9β1 integrin in glial tumor angiogenesis

PubMed Central

Walsh, Erin M.; Kim, Richard; Del Valle, Luis; Weaver, Michael; Sheffield, Joel; Lazarovici, Philip; Marcinkiewicz, Cezary

2012-01-01

NGF is a growth factor for which the role in the promotion of angiogenesis is still not completely understood. We found that NGF promotes the pathological neovascularization process in glioma through a direct interaction with α9β1 integrin, which is up-regulated on microvascular endothelial cells in cancer tissue. We propagated gHMVEC primary cells using a new method of immune-selection, and these cells demonstrated α9β1 integrin-dependent binding of NGF in a cell adhesion assay. Moreover, NGF induced gHMVEC proliferation and chemotaxis inhibited by specific blockers of α9β1 integrin, such as MLD-disintegrins and monoclonal antibody Y9A2. A Matrigel tube formation assay revealed that NGF significantly increased capillary-like growth from gHMVEC to a level comparable to treatment with VEGF. The snake venom disintegrin, VLO5, inhibited the agonistic effect of both growth factors, whereas the effect of Y9A2 was not statistically significant. Angiogenesis exogenously induced by NGF  was also α9β1-integrin dependent in an embryonic quail CAM system. However, angiogenesis pathologically induced by developing glioma in this system was only sensitive for inhibition with MLD-disintegrin, suggesting a more complex effect of cancer cells on the neovascularization process. The anti-angiogenic effect of MLD-disintegrins is probably related to their pro-apoptotic ability induced in activated tumoral endothelial cells. Therefore, the molecular basis of these disintegrins may be useful for developing new angiostatic pharmaceuticals for application in cancer therapy. PMID:22611032

Coffee, tea and caffeine intake and the risk of severe depression in middle-aged Finnish men: the Kuopio Ischaemic Heart Disease Risk Factor Study.

PubMed

Ruusunen, Anu; Lehto, Soili M; Tolmunen, Tommi; Mursu, Jaakko; Kaplan, George A; Voutilainen, Sari

2010-08-01

Only a few cross-sectional studies have assessed the association between coffee, tea and caffeine and the risk of depression. Our aim was to determine the association in a population-based cohort study. The population-based Kuopio Ischaemic Heart Disease Risk Factor Study cohort was recruited between 1984 and 1989 and followed until the end of 2006. We investigated the association between the intake of coffee, tea and caffeine and depression. Eastern Finland. Middle-aged men (n 2232). Altogether, forty-nine men received a discharge diagnosis of depression. We classified subjects into quartiles according to their mean daily coffee intake: non-drinkers (n 82), light drinkers (<375 ml/d, n 517), moderate drinkers (375-813 ml/d, n 1243) and heavy drinkers (>813 ml/d, n 390). Heavy drinkers had a decreased risk (RR = 0.28, 95 % CI 0.08, 0.98) for depression when compared with non-drinkers, after adjustment for age and examination years. Further adjustment for socio-economic status, alcohol consumption, smoking, maximal oxygen uptake, BMI and the energy-adjusted daily intakes of folate and PUFA did not attenuate this association (relative risk (RR) = 0.23, 95 % CI 0.06, 0.83). No associations were observed between depression and intake of tea (drinkers v. non-drinkers; RR = 1.19, 95 % CI 0.54, 2.23) or caffeine (highest quartile v. lowest quartile; RR = 0.99, 95 % CI 0.40, 2.45). Coffee consumption may decrease the risk of depression, whereas no association was found for tea and caffeine intake.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pastor-Soler, N.M.; Hu, D.; Schertz, E.

Metachromatic leukodystrophy (MLD) is an autosomal recessive lysosomal disorder caused by defective catabolism of sulfatide, an important sphingolipid in myelin. Late infantile (LI), juvenile and adult patients with MLD are found throughout the world. Mutational analysis of the ARSA gene in patients with MLD has resulted in the identification of about 30 mutations. Recently we identified a mutation in the ARSA gene that was present in all Navajo Indian patients tested with LIMLD. All of the patients were homozygous for the G to A change at position 1 of intron 4 which causes aberrant splicing and a low level ofmore » ARSA mRNA. This mutation had not been found in any non-Navajo population. However, recently we were sent samples from two Alaskan Eskimo siblings with LIMLD. Sequencing of amplified genomic DNA showed that the affected siblings were homozygous for the above mutation. A simple DNA-based test will permit accurate patient and carrier identification in both the Eskimo and Navajo populations. Many studies have focused on the migrations of the Amerindian, Athapaskan and Eskimo from eastern Asia to the new world and the intermingling of these peoples. While it is clear that Na-Dene speaking Navajo split from other Athapaskan tribes and migrated from western Canada and Alaska to the southwest area of the United States, a direct genetic connection between the Western Eskimo and the Navajo has not been made. The presence of the same unique mutation causing a fatal inherited disease in both populations may point to interaction between these peoples prior to the migration of the Navajos south about 1000 years ago.« less

Suppressive effects of standard-dose rosuvastatin therapy on the progression of coronary atherosclerosis in Japanese patients: the APOLLO study.

PubMed

Amemiya, Kisaki; Yokoi, Hiroyoshi; Domei, Takenori; Shirai, Shinichi; Ando, Kenji; Goya, Masahiko; Iwabuchi, Masashi

2014-01-01

We used quantitative coronary angiography (QCA) to investigate whether coronary plaque progression can be inhibited by controlling lipids with rosuvastatin at Japanese standard doses following elective percutaneous coronary intervention (PCI). A total of 143 patients who underwent elective PCI were randomized to either the rosuvastatin (5 or 2.5mg/day) or non-statin group. Changes from baseline in the minimal lumen diameter (MLD) and average lumen diameter (ALD) measured using QCA were analyzed in both target and non-target lesions. The changes in MLD and ALD from baseline to 24 months in the non-target lesions were significantly smaller in the rosuvastatin group than in the non-statin group (-0.079 ± 0.014 mm vs.-0.135 ± 0.019 mm, p=0.022; -0.062 ± 0.012 mmvs. -0.109 ± 0.016mm, p=0.025). The changes in MLD from six to 24 months in the target lesions were significantly lower in the rosuvastatin group than in the non-statin group among the patients treated with drug-eluting stents (-0.046 ± 0.108 mm vs. -0.133 ± 0.108 mm, p=0.009) versus those treated with bare-metal stents (-0.011 ± 0.094 mm vs. -0.015 ± 0.040 mm, p=0.255). The present study demonstrated that the administration of a standard dose of rosuvastatin slows coronary plaque progression and may prevent the late catch-up phenomenon associated with drug-eluting stents in patients who undergo elective PCI.

Current trends in stenting for aortic coarctation in Japan: Subanalysis of Japanese Society of Pediatric Interventional Cardiology (JPIC) stent survey.

PubMed

Fujii, Takanari; Tomita, Hideshi; Otsuki, Shinichi; Kobayashi, Toshiki; Ono, Yasuo; Yazaki, Satoshi; Kim, Sung-Hae; Nakanishi, Toshio

2016-02-01

Stenting for aortic coarctation (CoA) has been accepted as an alternative to surgery for adolescents and adults, but only a few case have been reported in Japan. The purpose of this study was to provide a detailed review of Japanese national data on stenting of CoA. In a subanalysis of the data of the Japanese Society of Pediatric Interventional Cardiology (JPIC), we identified 35 patients with CoA who underwent stenting. We analyzed procedural characteristics including factors that may have contributed to hemodynamic effectiveness, and we compared these parameters between the patients under and over 15 years of age. The mean ratio of balloon diameter/minimum lumen diameter (MLD) before stenting was 1.7 (range, 1.2-4.0), and the mean difference between the balloon diameter and the reference vessel diameter was -0.7 mm (range, -5.0 to +3.0 mm). %MLD/balloon diameter, which was defined as [(balloon diameter - MLD after dilation)/balloon diameter] × 100 predicted achievement of <10 mmHg pressure gradient after stenting. The sensitivity and the specificity of its cut-off of 7% were 93% and 47% (AUC, 0.7), respectively. There was no statistical difference between the two age groups under and over 15 years of age, in terms of selection criteria of stent size, balloon type used for deployment and immediate angiographic and hemodynamic result. Stenting for CoA was clinically effective with few complications in Japan, even in patients not fully grown. © 2015 Japan Pediatric Society.

What Are the Symptoms of Learning Disabilities?

MedlinePlus

... Difficulty with reading and/or writing Problems with math skills Difficulty remembering Problems paying attention Trouble following ... numbers. Other symptoms may include 7 : Difficulty with math-related word problems Trouble making change in cash ...

Investigating Difficulties of Learning Computer Programming in Saudi Arabia

ERIC Educational Resources Information Center

Alakeel, Ali M.

2015-01-01

Learning computer programming is one of the main requirements of many educational study plans in higher education. Research has shown that many students face difficulties acquiring reasonable programming skills during their first year of college. In Saudi Arabia, there are twenty-three state-owned universities scattered around the country that…

A Preschool Program for Preventing Learning Difficulties in Arithmetic.

ERIC Educational Resources Information Center

Dunlap, William P.

Described are many concrete readiness activities within ten broad categories that are designed to provide children with a solid foundation for mathematics and that help prevent learning difficulties in mathematics. Preschool mathematical experiences form the foundation for all studies in mathematics. Without a sufficient number of appropriate…

Associations among Sleep Problems, Learning Difficulties and Substance Use in Adolescence

ERIC Educational Resources Information Center

Fakier, Nuraan; Wild, Lauren G.

2011-01-01

This study investigated the relationships among sleep problems, learning difficulties and substance use in adolescence. Previous research suggests that these variables share an association with executive functioning deficits, and are intertwined. The sample comprised 427 adolescents (M age = 16 years) attending remedial schools and 276 adolescents…

Fractions Learning in Children with Mathematics Difficulties

ERIC Educational Resources Information Center

Tian, Jing; Siegler, Robert S.

2017-01-01

Learning fractions is difficult for children in general and especially difficult for children with mathematics difficulties (MD). Recent research on developmental and individual differences in fraction knowledge of children with MD and typically achieving (TA) children has demonstrated that U.S. children with MD start middle school behind their TA…

Fractions Learning in Children with Mathematics Difficulties

ERIC Educational Resources Information Center

Tian, Jing; Siegler, Robert S.

2016-01-01

Learning of fractions is difficult for children in general and especially difficult for children with mathematics difficulties (MD). Recent research on developmental and individual differences in fraction knowledge of MD and typically achieving (TA) children has demonstrated that U.S. children with MD start middle school behind TA peers in…

Learning Disabilities: A Practitioner's Scriptal Accommodation of More Recent Trends.

ERIC Educational Resources Information Center

Majsterek, David J.

Intended for teachers of students with learning disabilities, the paper reviews recent trends in research. The importance and the difficulty of keeping up with new developments in the field are noted. Research and theoretical considerations are presented for the following topic areas: definition and identification difficulties (including,…

Bullying Risk in Children with Learning Difficulties in Inclusive Educational Settings

ERIC Educational Resources Information Center

Luciano, Severina; Savage, Robert S.

2007-01-01

This study investigated whether students with learning difficulties (LDs) attending inclusive schools that eschewed segregated "pull out" programs reported more incidents of being bullied than their peers without LDs. Cognitive and self-perception factors associated with reports of peer victimization were also explored. Participants were…

Improving Student Understanding of Addition of Angular Momentum in Quantum Mechanics

ERIC Educational Resources Information Center

Zhu, Guangtian; Singh, Chandralekha

2013-01-01

We describe the difficulties advanced undergraduate and graduate students have with concepts related to addition of angular momentum in quantum mechanics. We also describe the development and implementation of a research-based learning tool, Quantum Interactive Learning Tutorial (QuILT), to reduce these difficulties. The preliminary evaluation…

Students' Difficulties With Multiple Representations in Introductory Mechanics

ERIC Educational Resources Information Center

Nguyen, Dong-Hai; Rebello, N. Sanjay

2011-01-01

Research in physics education indicates that the use of multiple representations in teaching and learning helps students become better problem-solvers. We report on a study to investigate students' difficulties in solving mechanics problems presented in multiple representations. We conducted teaching/learning interviews with 20 students in a…

Academic Difficulties Encountered by East Asian International University Students in New Zealand

ERIC Educational Resources Information Center

Lee, Boram; Farruggia, Susan P.; Brown, Gavin T. L.

2013-01-01

The study focused on learning difficulties experienced by East Asian International (EAI) students. Participants were 117 EAI students undertaking tertiary study at a major university, all were surveyed and 21 students were interviewed. The findings suggest that language limitations, academic content and learning styles were associated with…

Tackling the Difficulties in Learning Evolution: Effects of Adaptive Self-Explanation Prompts

ERIC Educational Resources Information Center

Neubrand, Charlotte; Harms, Ute

2017-01-01

Teaching and learning evolution is challenging. Biology education research shows that the underlying evolutionary concepts are poorly understood among students. This prevents a meaningful understanding of the central biological concepts. The instructional format of self-explanation prompts seems to be promising to respond to these difficulties.…

A Process Approach to Assessing Children with Learning Difficulties: Merging Assessment and Intervention.

ERIC Educational Resources Information Center

Smith, Corinne Roth

A multidimensional approach to assessment of children with learning difficulties is examined. The approach explores factors along five dimensions: (1) learner characteristics (motivation, social-emotional maturity, cognitive abilities and styles); (2) task-based contributors (match of tasks to maturational levels and to cognitive style); (3)…

Children with congenital limb deficiency in Norway: issues related to school life and health-related quality of life. A cross-sectional study.

PubMed

Johansen, Heidi; Dammann, Brede; Øinæs Andersen, Liv; Andresen, Inger-Lise

2016-09-01

To describe clinical features, issues related to school life and health-related quality of life (HRQOL) for children with congenital limb deficiency (CLD) and compare these children to Norwegian school children on HRQOL. Cross-sectional study. In 2010, a postal questionnaire, designed for this study and the Paediatric Quality of Life Inventory (PedsQL), was sent to 154 eligible parents of children with CLD, aged 6-18 years and registered at TRS National Resource Centre for Rare Disorders in Norway. Response rate 44% (n = 67), median age 11 years, 42% were girls. Of the total group, 46 had unilateral upper limb deficiency (UULD) and 21 had multiple/lower limb deficiency (MLD/LLD). The most common UULD was below-elbow deficiency, of these, 65% used grip-improving devices, and 35% used prostheses. Children with UULD-reported PedsQL score similar to Norwegian schoolchildren (NSC). The MLD/LLD group was heterogeneous; most had below-elbow/knee deficiency. In this group, PedsQL scores were reduced for physical and social functioning compared with NSC. Compared with children with UULD, more children with MLD/LLD were restricted in participation because of pain and fewer participated in physical education with peers. Most children with CLD participated with their peers and managed well in everyday life. Children with MLD/LLD seemed to have more challenges than children with UULD. Approximately one-third of all the children had assistive devices and/or practical assistance in school. Implications for Rehabilitation Most children with upper-limb deficiency (UULD) in Norway manage well in everyday life and have HRQOL equal to other Norwegian children. Many choose grip-improving devices instead of prostheses. Their preferences should be respected and taken into account as the need for new assistive devices arise. For children with pronounced disabilities, access to, and use of, assistive devices, adaptions and practical assistance may be important for participation. Cooperation with the child and the parents is necessary to find useful measures. Physical education and practical subjects may provide special challenges, both for children and their teachers. Children themselves often find good solutions and the tasks should be planned ahead in cooperation with them.

In Situ Infrared Spectroscopic Studies of Molecular Layer Deposition and Atomic Layer Etching Processes

NASA Astrophysics Data System (ADS)

DuMont, Jaime Willadean

In this thesis, in situ Fourier transform infrared (FTIR) spectroscopy was used to study: i) the growth and pyrolysis of molecular layer deposition (MLD) films. ii) the surface chemistry of atomic layer etching (ALE) processes. Atomic layer processes such as molecular layer deposition (MLD) and atomic layer etching (ALE) are techniques that can add or remove material with atomic level precision using sequential, self-limiting surface reactions. Deposition and removal processes at the atomic scale are powerful tools for many industrial and research applications such as energy storage and semiconductor nanofabrication. The first section of this thesis describes the chemistry of reactions leading to the MLD of aluminum and tin alkoxide polymer films known as "alucone" and "tincone", respectively. The subsequent pyrolysis of these films to produce metal oxide/carbon composites was also investigated. In situ FTIR spectroscopy was conducted to monitor surface species during MLD film growth and to monitor the films background infrared absorbance versus pyrolysis temperature. Ex situ techniques such as transmission electron microscopy (TEM), four-point probe and X-ray diffraction (XRD) were utilized to study the properties of the films post-pyrolysis. TEM confirmed that the pyrolyzed films maintained conformality during post-processing. Four-point probe monitored film resistivity versus pyrolysis temperature and XRD determined the film crystallinity. The second section of this thesis focuses on the surface chemistry of Al2O3 and SiO2 ALE processes, respectively. Thermal ALE processes have been recently developed which utilize sequential fluorination and ligand exchange reactions. An intimate knowledge of the surface chemistry is important in understanding the ALE process. In this section, the competition between the Al2O3 etching and AlF 3 growth that occur during sequential HF (fluorinating agent) and TMA (ligand exchange) exposures is investigated using in situ FTIR spectroscopy. Also included in this section is the first demonstration of thermal ALE for SiO2. In situ FTIR spectroscopy was conducted to monitor the loss of bulk Si-O vibrational modes corresponding to the removal of SiO2. FTIR was also used to monitor surface species during each ALE half cycle and to verify self-limiting behavior. X-ray reflectivity experiments were conducted to establish etch rates on thermal oxide silicon wafers.

Rule learning in autism: the role of reward type and social context.

PubMed

Jones, E J H; Webb, S J; Estes, A; Dawson, G

2013-01-01

Learning abstract rules is central to social and cognitive development. Across two experiments, we used Delayed Non-Matching to Sample tasks to characterize the longitudinal development and nature of rule-learning impairments in children with Autism Spectrum Disorder (ASD). Results showed that children with ASD consistently experienced more difficulty learning an abstract rule from a discrete physical reward than children with DD. Rule learning was facilitated by the provision of more concrete reinforcement, suggesting an underlying difficulty in forming conceptual connections. Learning abstract rules about social stimuli remained challenging through late childhood, indicating the importance of testing executive functions in both social and non-social contexts.

Learning Paths and Learning Styles in Dyslexia: Possibilites and Effectiveness--Case Study of Two Elementary School Students Aged 7 Years Old

ERIC Educational Resources Information Center

Tsampalas, Evangelos; Dimitrios, Sarris; Papadimitropoulou, Panagoula; Vergou, Maria; Zakopoulou, Victoria

2018-01-01

The difficulty in reading and writing, spelling mistakes and poor speech are considered as the main elements that characterize students with dyslexia. If one thinks that most of the things in a class are based on writing and reading, then the importance of such a learning difficulty is that it is recognized as soon as possible and with appropriate…

The Effect of the 4MAT Learning Model on the Achievement and Motivation of 7th Grade Students on the Subject of Particulate Nature of Matter and an Examination of Student Opinions on the Model

ERIC Educational Resources Information Center

Aktas, Idris; Bilgin, Ibrahim

2015-01-01

Background: Many researchers agree that students, especially primary students, have learning difficulties on the "Particulate Nature of Matter" unit. One reason for this difficulty is not considering individual differences for teaching science. In 4MAT model learning, environment is arranged according to individual differences. Purpose:…

Who Needs Learning Theory Anyway?

ERIC Educational Resources Information Center

Zemke, Ron

2002-01-01

Looks at a variety of learning theories: andragogy, behaviorism, cognitivism, conditions of learning, Gestalt, and social learning. Addresses the difficulty of selecting an appropriate theory for training. (JOW)

Natural History Study of Children With Metachromatic Leukodystrophy

ClinicalTrials.gov

2016-04-19

Lipid Metabolism Disorders; Metachromatic Leukodystrophy (MLD); Nervous System Diseases; Brain Diseases; Central Nervous System Diseases; Demyelinating Diseases; Metabolism, Inborn Errors; Genetic Diseases, Inborn; Sphingolipidoses; Hereditary Central Nervous System Demyelinating Diseases; Metabolic Inborn Brain Diseases; Lysosomal Storage Diseases; Metabolic Diseases; Sulfatidosis

A Five-Year Follow-Up on the Role of Educational Support in Preventing Dropout From Upper Secondary Education in Finland.

PubMed

Hakkarainen, Airi M; Holopainen, Leena K; Savolainen, Hannu K

2015-01-01

In this longitudinal study, we investigated the role of word reading and mathematical difficulties measured in 9th grade as factors for receiving educational support for learning in upper secondary education in Grades 10 to 12 (from ages 16 to 19) and furthermore as predictors of dropout from upper secondary education within 5 years after compulsory education. In addition, we studied the role of school achievement in Grades 9 and 11 in this prediction. The participants of this study were members of one age group of 16-year-old ninth graders (N = 595, females 302, males 293) in a midsized Finnish city, who were followed for 5 years after completing compulsory education. The path model results, where the effects of gender, educational track, and SES were controlled, showed, first, that students with academic learning difficulties received educational support for learning particularly in the 11th grade. Second, academic learning difficulties directly affected school achievement in the 9th grade, but no longer in the 11th grade. Third, mathematical difficulties directly predicted dropout from upper secondary education, and difficulties in both word reading and mathematics had an indirect effect through school achievement in Grades 9 and 11 on dropout. © Hammill Institute on Disabilities 2013.

Foreign Language Learning Difficulties and Teaching Strategies

ERIC Educational Resources Information Center

Banks, Tiffini

2008-01-01

Beginning foreign language (FL) courses in high school often have high numbers of learning disabled (LED) and at-risk students, perhaps because many students who are considered to be college bound begin foreign language study in middle school. This paper examines FL difficulties as well as effective strategies that others have used to conquer…

Mathematical Interventions for Secondary Students with Learning Disabilities and Mathematics Difficulties: A Meta-Analysis

ERIC Educational Resources Information Center

Jitendra, Asha K.; Lein, Amy E.; Im, Soo-hyun; Alghamdi, Ahmed A.; Hefte, Scott B.; Mouanoutoua, John

2018-01-01

This meta-analysis is the first to provide a quantitative synthesis of empirical evaluations of mathematical intervention programs implemented in secondary schools for students with learning disabilities and mathematics difficulties. Included studies used a treatment-control group design. A total of 19 experimental and quasi-experimental studies…

Learning Difficulties with Solids of Revolution: Classroom Observations

ERIC Educational Resources Information Center

Mofolo-Mbokane, Batseba; Engelbrecht, Johann; Harding, Ansie

2013-01-01

The study aims to identify areas of difficulty in learning about volumes of solids of revolution (VSOR) at a Further Education and Training college in South Africa. Students' competency is evaluated along five skill factors which refer to knowledge skills required to succeed in performing tasks relating to applications of the definite integral, in…

Educating Chinese, Japanese, and Korean International Students: Recommendations to American Professors

ERIC Educational Resources Information Center

Roy, Shelly R.

2013-01-01

This paper discusses the unique barriers and learning difficulties encountered by Chinese, Japanese, and Korean international students when they study at institutions of higher education in the US. These learning difficulties arise because of inability of some American professors to use discourse markers, summarize at the end of lectures, write…

Accessing Mainstream: Examining the Struggle for Parents of Children Who Have Learning Difficulties

ERIC Educational Resources Information Center

Kenny, Mairin; Shevlin, Michael; Walsh, Patricia Noonan; McNeela, Eileen

2005-01-01

In the past decade Ireland has witnessed substantial changes in policy and provision for children with general learning difficulties as government policies and legislation increasingly underpin the move towards more inclusive provision. Despite this series of policy initiatives parents of children who experience Down syndrome and general learning…

Psycho-Pedagogical Interventions in the Prevention and the Therapy of Learning Difficulties in the Field of Mathematics

ERIC Educational Resources Information Center

Anca, Maria; Hategan, Carolina

2009-01-01

In the given study dyscalculia is approached in the context of learning difficulties, but also in relation with damaged psychic processes and functions. The practical part of the study describes intervention models from the perspective of dyscalculia prevention and therapymaterialized in personalized intervention programs.

Machine Learning Based Evaluation of Reading and Writing Difficulties.

PubMed

Iwabuchi, Mamoru; Hirabayashi, Rumi; Nakamura, Kenryu; Dim, Nem Khan

2017-01-01

The possibility of auto evaluation of reading and writing difficulties was investigated using non-parametric machine learning (ML) regression technique for URAWSS (Understanding Reading and Writing Skills of Schoolchildren) [1] test data of 168 children of grade 1 - 9. The result showed that the ML had better prediction than the ordinary rule-based decision.

The Twin Twin Paradox: Exploring Student Approaches to Understanding Relativistic Concepts

ERIC Educational Resources Information Center

Cormier, Sebastien; Steinberg, Richard

2010-01-01

A great deal has long been known about student difficulties connecting real-world experiences with what they are learning in their physics classes, making learning basic ideas of classical physics challenging. Understanding these difficulties has led to the development of many instructional approaches that have been shown to help students make…

CAS-Induced Difficulties in Learning Mathematics?

ERIC Educational Resources Information Center

Jankvist, Uffe Thomas; Misfeldt, Morten

2015-01-01

In recent years computer algebra systems (CAS) have become an integrated part of the upper secondary school mathematics program. Despite the many positive possibilities of CAS, there also seems to be a flip side of the coin in relation to actual difficulties in learning mathematics, not least because a strong dependence on CAS for mathematical…

Multigenerational Learning for Expanding the Educational Involvement of Bilinguals Experiencing Academic Difficulties

ERIC Educational Resources Information Center

Martínez-Álvarez, Patricia

2017-01-01

Focusing on two bilingual children experiencing learning difficulties, I explore the scientific representations these students generate in an afterschool programme where they have opportunities to exercise agency. In the programme, children use a digital camera to document science in their lives and engage in conversations about the products they…

An Evolving Approach to Learning Problem Solving and Program Development: The Distributed Learning Model

ERIC Educational Resources Information Center

Deek, Fadi; Espinosa, Idania

2005-01-01

Traditionally, novice programmers have had difficulties in three distinct areas: breaking down a given problem, designing a workable solution, and debugging the resulting program. Many programming environments, software applications, and teaching tools have been developed to address the difficulties faced by these novices. Along with advancements…

Multiple Goals Perspective in Adolescent Students with Learning Difficulties

ERIC Educational Resources Information Center

Nunez, Jose Carlos; Gonzalez-Pienda, Julio Antonio; Rodriguez, Celestino; Valle, Antonio; Gonzalez-Cabanach, Ramon; Rosario, Pedro

2011-01-01

In the present work, the hypothesis of the existence of diverse motivational profiles in students with learning difficulties (LD) and the differential implications for intervention in the classroom are analyzed. Various assessment scales (academic goals, self-concept, and causal attributions) were administered to a sample of 259 students with LD,…

Observing and Analyzing Children's Mathematical Development, Based on Action Theory

ERIC Educational Resources Information Center

Bunck, M. J. A.; Terlien, E.; van Groenestijn, M.; Toll, S. W. M.; Van Luit, J. E. H.

2017-01-01

Children who experience difficulties with learning mathematics should be taught by teachers who focus on the child's best way of learning. Analyses of the mathematical difficulties are necessary for fine-tuning mathematics education to the needs of these children. For this reason, an instrument for Observing and Analyzing children's Mathematical…

Difficulties in Learning and Teaching Statistics: Teacher Views

ERIC Educational Resources Information Center

Koparan, Timur

2015-01-01

The purpose of this study is to define teacher views about the difficulties in learning and teaching middle school statistics subjects. To serve this aim, a number of interviews were conducted with 10 middle school maths teachers in 2011-2012 school year in the province of Trabzon. Of the qualitative descriptive research methods, the…

Students with Disabilities, Learning Difficulties and Disadvantages: Policies, Statistics and Indicators--2007

ERIC Educational Resources Information Center

OECD Publishing (NJ3), 2008

2008-01-01

This book provides an internationally comparable set of indicators on educational provision for students with disabilities, learning difficulties and disadvantages (DDD). It highlights the number of students involved, where they are educated--special schools, special classes or regular classes--and in what phases of education--pre-primary,…

Multi-sensory Environments: An Exploration of Their Potential for Young People with Profound and Multiple Learning Difficulties.

ERIC Educational Resources Information Center

Mount, Helen; Cavet, Judith

1995-01-01

This article addresses the controversy concerning multisensory environments for children and adults with profound and multiple learning difficulties, from a British perspective. The need for critical evaluation of such multisensory interventions as the "snoezelen" approach and the paucity of relevant, rigorous research on educational…

Learning Difficulties Experienced by Grade 12 South African Students in the Chemical Representation of Phenomena

ERIC Educational Resources Information Center

Ramnarain, Umesh; Joseph, Aleyamma

2012-01-01

This study investigated the learning difficulties of grade 12 South African students in a national chemistry examination. A quantitative analysis of students' performance in the examination revealed there was a significant difference between student performance in questions where students needed to execute a transformation across levels of…

Language Difficulties of International Students in Australia: The Effects of Prior Learning Experience

ERIC Educational Resources Information Center

Sawir, Erlenawati

2005-01-01

Globalisation has placed a growing importance on English language speaking and listening. Prior research indicates that many international students from Asia, studying in Australia, face serious learning difficulties and lack confidence in speaking and taking a proactive role in classrooms. The paper reports on data gathered in interviews with…

The Relation between Children's Conceptual Functioning with Color and Color Term Acquisition

ERIC Educational Resources Information Center

Kowalski, Kurt; Zimiles, Herbert

2006-01-01

Young children experience considerable difficulty in learning their first few color terms. One explanation for this difficulty is that initially they lack a conceptual representation of color sufficiently abstract to support word meaning. This hypothesis, that prior to learning color terms children do not represent color as an abstraction, was…

A Mobile Application to Improve Learning Performance of Dyslexic Children with Writing Difficulties

ERIC Educational Resources Information Center

Tariq, Rabbia; Latif, Seemab

2016-01-01

A neurological learning disability, termed as Dyslexia, is characterized by difficulties in various aspects of writing skills making the individuals unable to develop age-appropriate and ability-appropriate functional skills. In Pakistan, lack of dyslexia awareness and remedial education training restrains the remediation of dyslexic children at…

Morphological Processing and Learning to Read: The Case of Deaf Children

ERIC Educational Resources Information Center

Berthiaume, Rachel; Daigle, Daniel

2014-01-01

Many deaf students encounter great difficulty in learning to read. Typically, research has cited deaf students' difficulties to use phonological processing as the source of their reading deficit. However, recent studies have shown that morphological processing also plays an important part in reading. Since morphological units are visually…

Differences in the Mathematics-Vocabulary Knowledge of Fifth-Grade Students with and without Learning Difficulties

ERIC Educational Resources Information Center

Forsyth, Suzanne R.; Powell, Sarah R.

2017-01-01

The purpose of this pilot study was to explore the impact of mathematics and reading learning difficulties on the mathematics-vocabulary understanding of fifth-grade students. Students (n = 114) completed three measures: mathematics computation, general vocabulary, and mathematics vocabulary. Based on performance on the mathematics computation and…

The effects of autonomous difficulty selection on engagement, motivation, and learning in a motion-controlled video game task.

PubMed

Leiker, Amber M; Bruzi, Alessandro T; Miller, Matthew W; Nelson, Monica; Wegman, Rebecca; Lohse, Keith R

2016-10-01

This experiment investigated the relationship between motivation, engagement, and learning in a video game task. Previous studies have shown increased autonomy during practice leads to superior retention of motor skills, but it is not clear why this benefit occurs. Some studies suggest this benefit arises from increased motivation during practice; others suggest the benefit arises from better information processing. Sixty novice participants were randomly assigned to a self-controlled group, who chose the progression of difficulty during practice, or to a yoked group, who experienced the same difficulty progression but did not have choice. At the end of practice, participants completed surveys measuring intrinsic motivation and engagement. One week later, participants returned for a series of retention tests at three different difficulty levels. RM-ANCOVA (controlling for pre-test) showed that the self-controlled group had improved retention compared to the yoked group, on average, β=46.78, 95% CI=[2.68, 90.87], p=0.04, but this difference was only statistically significant on the moderate difficulty post-test (p=0.004). The self-controlled group also showed greater intrinsic motivation during practice, t(58)=2.61, p=0.01. However, there was no evidence that individual differences in engagement (p=0.20) or motivation (p=0.87) were associated with learning, which was the relationship this experiment was powered to detect. These data are inconsistent with strictly motivational accounts of how autonomy benefits learning, instead suggesting the benefits of autonomy may be mediated through other mechanisms. For instance, within the information processing framework, the learning benefits may emerge from learners appropriately adjusting difficulty to maintain an appropriate level of challenge (i.e., maintaining the relationship between task demands and cognitive resources). Copyright © 2016 Elsevier B.V. All rights reserved.

Current management for word finding difficulties by speech-language therapists in South African remedial schools.

PubMed

de Rauville, Ingrid; Chetty, Sandhya; Pahl, Jenny

2006-01-01

Word finding difficulties frequently found in learners with language learning difficulties (Casby, 1992) are an integral part of Speech-Language Therapists' management role when working with learning disabled children. This study investigated current management for word finding difficulties by 70 Speech-Language Therapists in South African remedial schools. A descriptive survey design using a quantitative and qualitative approach was used. A questionnaire and follow-up focus group discussion were used to collect data. Results highlighted the use of the Renfrew Word Finding Scale (Renfrew, 1972, 1995) as the most frequently used formal assessment tool. Language sample analysis and discourse analysis were the most frequently used informal assessment procedures. Formal intervention programmes were generally not used. Phonetic, phonemic or phonological cueing were the most frequently used therapeutic strategies. The authors note strengths and raise concerns about current management for word finding difficulties in South African remedial schools, particularly in terms of bilingualism. Opportunities are highlighted regarding the development of assessment and intervention measures relevant to the diverse learning disabled population in South Africa.

Rule Learning in Autism: The Role of Reward Type and Social Context

PubMed Central

Jones, E. J. H.; Webb, S. J.; Estes, A.; Dawson, G.

2013-01-01

Learning abstract rules is central to social and cognitive development. Across two experiments, we used Delayed Non-Matching to Sample tasks to characterize the longitudinal development and nature of rule-learning impairments in children with Autism Spectrum Disorder (ASD). Results showed that children with ASD consistently experienced more difficulty learning an abstract rule from a discrete physical reward than children with DD. Rule learning was facilitated by the provision of more concrete reinforcement, suggesting an underlying difficulty in forming conceptual connections. Learning abstract rules about social stimuli remained challenging through late childhood, indicating the importance of testing executive functions in both social and non-social contexts. PMID:23311315

Searching for Interference Effects in Learning New Face-Name Associations

PubMed Central

James, Lori E.; Tauber, Sarah K.; McMahan, Ethan A.; Oberle, Shalyn; Martinez, Ashley P.; Fogler, Kethera A.

2012-01-01

In 3 experiments, we attempted to increase interference using experimental manipulations in a face-name learning paradigm. All experiments included young and older adult participants because aging is associated with increases in both susceptibility to interference and difficulty in learning face-name associations. None of the experiments produced interference for either age group: The inclusion of confusable (i.e., ambiguous) names and occupations, having to learn an additional piece of information in association with each face, and requiring participants to guess when uncertain all failed to negatively impact name learning. Interference does not appear to be the critical mechanism underlying the difficulty of learning proper names, and it cannot account for older adults’ disproportionate decline in name-learning ability. PMID:22292565

Self-reported learning difficulties and dietary intake in Norwegian adolescents.

PubMed

Øverby, Nina Cecilie; Lüdemann, Eva; Høigaard, Rune

2013-11-01

The academic performance of children impacts future educational attainment which may increase socioeconomic status which again influences their health. One of several factors that might affect academic performance is the diet. The aim of this study was to investigate the cross sectional relation between diet and self-reported reading-, writing-, and mathematical difficulties in Norwegian adolescents. In total, 475 ninth- and tenth-grade students out of 625 eligible ones from four different secondary schools in three different municipalities in Vest-Agder County, Norway, participated, giving a participation rate of 77%. The students filled in a questionnaire with food frequency questions of selected healthy and unhealthy food items, questions of meal frequency and different learning difficulties. Regular breakfast was significantly associated with decreased odds of both writing and reading difficulties (OR: 0.44 (0.2-0.8), p = 0.01) and mathematical difficulties (OR: 0.33 (0.2-0.6), p ≤ 0.001). In addition, having lunch, dinner and supper regularly were associated with decreased odds of mathematical difficulties. Further, a high intake of foods representing a poor diet (sugar-sweetened soft drinks, sweets, chocolate, savory snacks, pizza and hot dogs) was significantly associated with increased odds of mathematical difficulties. Having a less-frequent intake of unhealthy foods and not skipping meals are associated with decreased odds of self-reported learning difficulties in Norwegian adolescents in this study. The results of this study support the need for a larger study with a more representative sample.

What Research Says about Text Complexity and Learning to Read

ERIC Educational Resources Information Center

Allington, Richard L.; McCuiston, Kimberly; Billen, Monica

2015-01-01

The CCSS framework indicates more difficult texts are to be used with students. However, the rationale for increasing text difficulty, decreasing text difficulty, is unsupported by the research that shows texts have been increasing in difficulty for at least 50 years. Oral reading accuracy is a traditional method of estimating text difficulty. For…

Learner-Controlled Practice Difficulty in the Training of a Complex Task: Cognitive and Motivational Mechanisms

ERIC Educational Resources Information Center

Hughes, Michael G.; Day, Eric Anthony; Wang, Xiaoqian; Schuelke, Matthew J.; Arsenault, Matthew L.; Harkrider, Lauren N.; Cooper, Olivia D.

2013-01-01

An inherent aspect of learner-controlled instructional environments is the ability of learners to affect the degree of difficulty faced during training. However, research has yet to examine how learner-controlled practice difficulty affects learning. Based on the notion of "desirable difficulties" (Bjork, 1994), this study examined the…

Science teacher's perception about science learning experiences as a foundation for teacher training program

NASA Astrophysics Data System (ADS)

Tapilouw, Marisa Christina; Firman, Harry; Redjeki, Sri; Chandra, Didi Teguh

2017-05-01

Teacher training is one form of continuous professional development. Before organizing teacher training (material, time frame), a survey about teacher's need has to be done. Science teacher's perception about science learning in the classroom, the most difficult learning model, difficulties of lesson plan would be a good input for teacher training program. This survey conducted in June 2016. About 23 science teacher filled in the questionnaire. The core of questions are training participation, the most difficult science subject matter, the most difficult learning model, the difficulties of making lesson plan, knowledge of integrated science and problem based learning. Mostly, experienced teacher participated training once a year. Science training is very important to enhance professional competency and to improve the way of teaching. The difficulties of subject matter depend on teacher's education background. The physics subject matter in class VIII and IX are difficult to teach for most respondent because of many formulas and abstract. Respondents found difficulties in making lesson plan, in term of choosing the right learning model for some subject matter. Based on the result, inquiry, cooperative, practice are frequently used in science class. Integrated science is understood as a mix between Biology, Physics and Chemistry concepts. On the other hand, respondents argue that problem based learning was difficult especially in finding contextual problem. All the questionnaire result can be used as an input for teacher training program in order to enhanced teacher's competency. Difficult concepts, integrated science, teaching plan, problem based learning can be shared in teacher training.

The Role of Self-Assessment in Foundation of Mathematics Learning

NASA Astrophysics Data System (ADS)

Masriyah

2018-01-01

This research is motivated by the low performance of students who took Foundations of Mathematics course. This study was aimed to describe (1) the learning outcomes of students who learned Mathematics Foundation after learning axiomatic applying self-assessment; (2) the difficulty of students and the alternative solutions; and (3) the response of students toward Foundation of Mathematics learning taught by applying self-assessment. This research was a descriptive research. The subjects were 25 mathematics students who studied Foundation of Mathematics in odd semester of the 2015/2016 academic year. Data collection was done using questionnaires, and testing methods. Based on the results of data analysis, it can be concluded that the learning outcomes of students were categorized as “good.” Student responses were positive; the difficulties lied in the sub material: Classification of Axiom Systems and the requirements, Theorem and how the formation, and finite geometry. The alternatives deal with these difficulties are to give emphasis and explanation as needed on these materials, as well as provide some more exercises to reinforce their understanding.

Comparing a 7-day diary vs. 24 h-recall for estimating fluid consumption in overweight and obese Mexican women.

PubMed

Hernández-Cordero, Sonia; López-Olmedo, Nancy; Rodríguez-Ramírez, Sonia; Barquera-Cervera, Simón; Rivera-Dommarco, Juan; Popkin, Barry

2015-10-07

High intake of sugar-sweetened beverages (SSB) is linked to increased weight, energy intake, and diabetes. Even though the increasing interest on beverages and water intake, there are few dietary tools carefully validated. The purpose of this paper is to compare a fluid intake 7-day diary against a 24-h recall questionnaire to estimate the fluid consumption in overweight and obese women participating in a randomized controlled trial in Mexico. This cross-sectional study explored the correlation of reported fluid consumption between two methods: 3-day 24-hr recalls and 7-day diary beverage registry in overweight and obese Mexican women aged 18-45 y (n = 190). There was no difference on median estimated volume (mL/d), nor the median estimated energy (kcal/d) from total beverage consumption registered by the two dietary tools. The crude and rank correlation among the two dietary instruments was high for total fluid consumption in mL/d r = 0.7, p < 0.001 (crude and rank correlation) and for fluid consumption measured as energy intake: r = 0.7; p < 0.001 crude, and r = 0.5; p < 0.001 rank correlation. By type of beverage, the more meaningful rank correlations were for fluid intake in: mL/d, water, alcohol beverages, and SSB; and in kcal/d, alcohol beverages and SSBs (rank correlation ≥ 0.6). Overall, the 7-day diary showed high and strong rank correlations with that reported in the 24-h recall, suggesting that the diary method is a valid dietary tool to evaluate total fluid, water and SSB intake in this population.

Start-up of a sequential dry anaerobic digestion of paunch under psychrophilic and mesophilic temperatures.

PubMed

Nkemka, Valentine Nkongndem; Hao, Xiying

2018-04-01

The present laboratory study evaluated the sequential leach bed dry anaerobic digestion (DAD) of paunch under psychrophilic (22°C) and mesophilic (40°C) temperatures. Three leach bed reactors were operated under the mesophilic temperature in sequence at a solid retention time (SRT) of 40d with a new batch started 27d into the run of the previous one. A total of six batches were operated for 135d. The results showed that the mesophilic DAD of paunch was efficient, reaching methane yields of 126.9-212.1mLg -1 volatile solid (VS) and a VS reduction of 32.9-55.5%. The average daily methane production rate increased from 334.3mLd -1 to 571.4mLd -1 and 825.7mLd -1 when one, two and three leach bed reactors were in operation, respectively. The psychrophilic DAD of paunch was operated under a SRT of 100d and a total of three batches were performed in sequence for 300d with each batch starting after completion of the previous one. Improvements in the methane yield from 93.9 to 107.3 and 148.3mLg -1 VS and VS reductions of 24.8, 30.2 and 38.6% were obtained in the consecutive runs, indicating the adaptation of anaerobic microbes from mesophilic to psychrophilic temperatures. In addition, it took three runs for anaerobic microbes to reduce the volatile fatty acid accumulation observed in the first and second trials. This study demonstrates the potential of renewable energy recovery from paunch under psychrophilic and mesophilic temperatures. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Effect of the Barrier Layer on the Upper Ocean Response to MJO Forcing

NASA Astrophysics Data System (ADS)

Bulusu, S.

2014-12-01

Recently, attention has been given to an upper ocean feature known as the Barrier Layer, which has been shown to impact meteorological phenomena from ENSO to tropical cyclones by suppressing vertical mixing, which reduces sea surface cooling and enhances surface heat fluxes. The calculation defines the Barrier Layer as the difference between the Isothermal Layer Depth (ILD) and Mixed Layer Depth (MLD). Proper representation of these features relies on precise observations of SSS to attain accurate measurements of the MLD and subsequently, the BLT. Compared to the many available in situ SSS measurements, the NASA Aquarius salinity mission currently obtains the closest observations to the true SSS. The role of subsurface features will be better understood through increased accuracy of SSS measurements. In this study BLT estimates are derived from satellite measurements using a multilinear regression model (MRM) in the Indian Ocean. The MRM relates BLT to satellite derived SSS, sea surface temperature (SST) and sea surface height anomalies (SSHA). Besides being a variable that responds passively to atmospheric conditions, SSS significantly controls upper ocean density and therefore the MLD. The formation of a Barrier Layer can lead to possible feedbacks that impact the atmospheric component of the Madden-Julian Oscillation (MJO), as stated as one of the three major hypotheses of the DYNAMO field campaign. This layer produces a stable stratification, reducing vertical mixing, which influences surface heat fluxes and thus could possibly impact atmospheric conditions during the MJO. Establishing the magnitude and extent of SSS variations during the MJO will be a useful tool for data assimilation into models to correctly represent both oceanic thermodynamic characteristics and atmospheric processes during intraseasonal variations.

Fully automatic quantitative assessment of emphysema in computed tomography: comparison with pulmonary function testing and normal values.

PubMed

Heussel, C P; Herth, F J F; Kappes, J; Hantusch, R; Hartlieb, S; Weinheimer, O; Kauczor, H U; Eberhardt, R

2009-10-01

Characterisation and quantification of emphysema are necessary for planning of local treatment and monitoring. Sensitive, easy to measure, and stable parameters have to be established and their relation to the well-known pulmonary function testing (PFT) has to be investigated. A retrospective analysis of 221 nonenhanced thin-section MDCT with a corresponding PFT was carried out, with a subgroup analysis in 102 COPD stage III+IV, 44 COPD stage 0, and 33 investigations into interstitial lung disease (ILD). The in-house YACTA software was used for automatic quantification of lung and emphysema volume [l], emphysema index, mean lung density (MLD [HU]) and 15(th) percentile [HU]. CT-derived lung volume is significantly smaller in ILD (3.8) and larger in COPD (7.2) than in controls (5.9, p < 0.0001). Emphysema volume and index are significantly higher in COPD than in controls (3.2 vs. 0.5, p < 0.0001, 45% vs. 8%, p < 0.0001). MLD and 15(th) percentile are significantly smaller in COPD (-877/-985, p < 0.0001) and significantly higher in ILD (-777, p < 0.0006/-914, p < 0.0001) than in controls (-829/-935). A relevant amount of COPD patients apparently do not suffer from emphysema, while controls who do not fulfil PFT criteria for COPD also demonstrate CT features of emphysema. Automatic quantification of thin-section CT delivers convincing parameters and ranges that are able to differentiate among emphysema, control and ILD. An emphysema index of lower 20%, MLD higher than -850, and 15(th) percentile lower than -950 might be regarded as normal (thin-section, nonenhanced, B40, YACTA). These ranges might be helpful in the judgement of individual measures.

Connections of the Auditory Brainstem in a Songbird, Taeniopygia guttata. II. Projections of Nucleus Angularis and Nucleus Laminaris to the Superior Olive and Lateral Lemniscal Nuclei

PubMed Central

Krützfeldt, Nils O.E.; Logerot, Priscilla; Kubke, M. Fabiana; Wild, J. Martin

2013-01-01

Three nuclei of the lateral lemniscus are present in the zebra finch, ventral (LLV), intermediate (LLI), and dorsal (LLD). LLV is separate from the superior olive (OS): it lies closer to the spinal lemniscus and extends much further rostrally around the pontine periphery. LLI extends from a caudal position ventrolateral to the principal sensory trigeminal nucleus (LLIc) to a rostral position medial to the ventrolateral parabrachial nucleus (LLIr). LLD consists of posterior (LLDp) and anterior (LLDa) parts, which are largely coextensive rostrocaudally, although LLDa lies medial to LLDp. All nuclei are identifiable on the basis of cytochrome oxidase activity. The cochlear nucleus angularis (NA) and the third-order nucleus laminaris (NL) project on OS predominantly ipsilaterally, on LLV and LLI predominantly contralaterally, and on LLD contralaterally only. The NA projections are heavier than those of NL and differ from them primarily in their terminations within LLD: NA projects to LLDp, whereas NL projects to LLDa. In this the projections are similar to those in the barn owl (Takahashi and Konishi [1988] J Comp Neurol 274:212–238), in which time and intensity pathways remain separate as far as the central nucleus of the inferior colliculus (MLd). In contrast, in the zebra finch, although NA and NL projections remain separate within LLD, the projections of LLDa and LLDp become intermixed within MLd (Wild et al., J Comp Neurol, this issue), consistent with the intermixing of the direct NA and NL projections to MLd (Krützfeldt et al., J Comp Neurol, this issue). J. Comp. Neurol. 518:2135–2148, 2010. PMID:20394062

Scan-rescan reproducibility of CT densitometric measures of emphysema

NASA Astrophysics Data System (ADS)

Chong, D.; van Rikxoort, E. M.; Kim, H. J.; Goldin, J. G.; Brown, M. S.

2011-03-01

This study investigated the reproducibility of HRCT densitometric measures of emphysema in patients scanned twice one week apart. 24 emphysema patients from a multicenter study were scanned at full inspiration (TLC) and expiration (RV), then again a week later for four scans total. Scans for each patient used the same scanner and protocol, except for tube current in three patients. Lung segmentation with gross airway removal was performed on the scans. Volume, weight, mean lung density (MLD), relative area under -950HU (RA-950), and 15th percentile (PD-15) were calculated for TLC, and volume and an airtrapping mask (RA-air) between -950 and -850HU for RV. For each measure, absolute differences were computed for each scan pair, and linear regression was performed against volume difference in a subgroup with volume difference <500mL. Two TLC scan pairs were excluded due to segmentation failure. The mean lung volumes were 5802 +/- 1420mL for TLC, 3878 +/- 1077mL for RV. The mean absolute differences were 169mL for TLC volume, 316mL for RV volume, 14.5g for weight, 5.0HU for MLD, 0.66p.p. for RA-950, 2.4HU for PD-15, and 3.1p.p. for RA-air. The <500mL subgroup had 20 scan pairs for TLC and RV. The R2 values were 0.8 for weight, 0.60 for MLD, 0.29 for RA-950, 0.31 for PD-15, and 0.64 for RA-air. Our results indicate that considerable variability exists in densitometric measures over one week that cannot be attributed to breathhold or physiology. This has implications for clinical trials relying on these measures to assess emphysema treatment efficacy.

Patient feature based dosimetric Pareto front prediction in esophageal cancer radiotherapy.

PubMed

Wang, Jiazhou; Jin, Xiance; Zhao, Kuaike; Peng, Jiayuan; Xie, Jiang; Chen, Junchao; Zhang, Zhen; Studenski, Matthew; Hu, Weigang

2015-02-01

To investigate the feasibility of the dosimetric Pareto front (PF) prediction based on patient's anatomic and dosimetric parameters for esophageal cancer patients. Eighty esophagus patients in the authors' institution were enrolled in this study. A total of 2928 intensity-modulated radiotherapy plans were obtained and used to generate PF for each patient. On average, each patient had 36.6 plans. The anatomic and dosimetric features were extracted from these plans. The mean lung dose (MLD), mean heart dose (MHD), spinal cord max dose, and PTV homogeneity index were recorded for each plan. Principal component analysis was used to extract overlap volume histogram (OVH) features between PTV and other organs at risk. The full dataset was separated into two parts; a training dataset and a validation dataset. The prediction outcomes were the MHD and MLD. The spearman's rank correlation coefficient was used to evaluate the correlation between the anatomical features and dosimetric features. The stepwise multiple regression method was used to fit the PF. The cross validation method was used to evaluate the model. With 1000 repetitions, the mean prediction error of the MHD was 469 cGy. The most correlated factor was the first principal components of the OVH between heart and PTV and the overlap between heart and PTV in Z-axis. The mean prediction error of the MLD was 284 cGy. The most correlated factors were the first principal components of the OVH between heart and PTV and the overlap between lung and PTV in Z-axis. It is feasible to use patients' anatomic and dosimetric features to generate a predicted Pareto front. Additional samples and further studies are required improve the prediction model.

Physical and Biogeochemical Controls of the Phytoplankton Blooms in North Western Mediterranean Sea: A Multiplatform Approach Over a Complete Annual Cycle (2012-2013 DEWEX Experiment)

NASA Astrophysics Data System (ADS)

Mayot, Nicolas; D'Ortenzio, Fabrizio; Taillandier, Vincent; Prieur, Louis; de Fommervault, Orens Pasqueron; Claustre, Hervé; Bosse, Anthony; Testor, Pierre; Conan, Pascal

2017-12-01

The North Western Mediterranean Sea exhibits recurrent and significant autumnal and spring phytoplankton blooms. The existence of these two blooms coincides with typical temperate dynamics. To determine the potential control of physical and biogeochemical factors on these phytoplankton blooms, data from a multiplatform approach (combining ships, Argo and BGC-Argo floats, and bio-optical gliders) were analyzed in association with satellite observations in 2012-2013. The satellite framework allowed a simultaneous analysis over the whole annual cycle of in situ observations of mixed layer depth, photosynthetical available radiation, particle backscattering, nutrients (nitrate and silicate), and chlorophyll-a concentrations. During the year 2012-2013, satellite ocean color observations, confirmed by in situ data, have revealed the existence of two areas (or bioregions) with comparable autumnal blooms but contrasting spring blooms. In both bioregions, the ratio of the euphotic zone (defined as the isolume 0.415 mol photons m-2 d-1, Z0.415) and the MLD identified the initiation of the autumnal bloom, as well as the maximal annual increase in [Chl-a] in spring. In fact, the autumnal phytoplankton bloom might be initiated by mixing of the summer shallowing deep chlorophyll maximum, while the spring restratification (when Z0.415/MLD ratio became >1) might induce surface phytoplankton production that largely overcomes the losses. Finally, winter deep convection events that took place in one of the bioregions induced higher net accumulation rate of phytoplankton in spring associated with a diatom-dominated phytoplankton community principally. We suggest that very deep winter MLD lead to an increase in surface silicates availability, which favored the development of diatoms.

TU-C-17A-10: Patient Features Based Dosimetric Pareto Front Prediction In Esophagus Cancer Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, J; Zhao, K; Peng, J

2014-06-15

Purpose: The purpose of this study is to study the feasibility of the dosimetric pareto front (PF) prediction based on patient anatomic and dosimetric parameters for esophagus cancer patients. Methods: Sixty esophagus patients in our institution were enrolled in this study. A total 2920 IMRT plans were created to generated PF for each patient. On average, each patient had 48 plans. The anatomic and dosimetric features were extracted from those plans. The mean lung dose (MLD), mean heart dose (MHD), spinal cord max dose and PTV homogeneous index (PTVHI) were recorded for each plan. The principal component analysis (PCA) wasmore » used to extract overlap volume histogram (OVH) features between PTV and other critical organs. The full dataset was separated into two parts include the training dataset and the validation dataset. The prediction outcomes were the MHD and MLD for the current study. The spearman rank correlation coefficient was used to evaluate the correlation between the anatomical features and dosimetric features. The PF was fit by the the stepwise multiple regression method. The cross-validation method was used to evaluation the model. Results: The mean prediction error of the MHD was 465 cGy with 100 repetitions. The most correlated factors were the first principal components of the OVH between heart and PTV, and the overlap between heart and PTV in Z-axis. The mean prediction error of the MLD was 195 cGy. The most correlated factors were the first principal components of the OVH between lung and PTV, and the overlap between lung and PTV in Z-axis. Conclusion: It is feasible to use patients anatomic and dosimetric features to generate a predicted PF. Additional samples and further studies were required to get a better prediction model.« less

Impact of intra-seasonal oscillations of Indian summer monsoon on biogeochemical constituents of North Indian Ocean

NASA Astrophysics Data System (ADS)

Das, D.; Chakrabarty, M.; Goswami, S.; Basu, D.; Chaudhuri, S.

2018-05-01

The intra-seasonal perturbations in the atmospheric weather are closely related to the variability in the ocean circulation. NASA Ocean Biogeochemical Model (NOBM) couples the oceanic general circulation and the radiative forcing. The NOBM model products of nitrate, total chlorophyll, and mixed layer depth (MLD) collected during the period from 1998 to 2007 as well as the sea surface temperature (SST), precipitation, outgoing long wave radiation (OLR), and wind are considered in this study to identify the influence of intra-seasonal oscillation (ISO) of Indian summer monsoon (ISM) on the biogeochemical constituents of Bay of Bengal (BOB) (6°-22° N; 80°-100° E) and Arabian Sea (AS) (3°-17° N; 55°-73.5° E) of North Indian Ocean (NIO). The active and break phases are the most significant components of ISO during ISM. The result of the study reveals that the upper ocean biology and chemistry significantly vary during the said phases of ISM. The nitrate, total chlorophyll, and MLD are observed to be strongly correlated with the ISO of ISM. The result shows that, during ISO of ISM, the concentration of nitrate and chlorophyll is strongly and positively correlated both in BOB and AS. However, the correlation is more in AS, endorsing that the Arabian Sea is more nutrient reach than Bay of Bengal. Nitrate and MLD, on the other hand, are strongly but negatively correlated in the said basins of North Indian Ocean (NIO). The forcing behind the variability of the biogeochemical constituents of BOB and AS during active and break phases of ISM is identified through the analyses of SST, precipitation, OLR, and wind.

Patient feature based dosimetric Pareto front prediction in esophageal cancer radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Jiazhou; Zhao, Kuaike; Peng, Jiayuan

2015-02-15

Purpose: To investigate the feasibility of the dosimetric Pareto front (PF) prediction based on patient’s anatomic and dosimetric parameters for esophageal cancer patients. Methods: Eighty esophagus patients in the authors’ institution were enrolled in this study. A total of 2928 intensity-modulated radiotherapy plans were obtained and used to generate PF for each patient. On average, each patient had 36.6 plans. The anatomic and dosimetric features were extracted from these plans. The mean lung dose (MLD), mean heart dose (MHD), spinal cord max dose, and PTV homogeneity index were recorded for each plan. Principal component analysis was used to extract overlapmore » volume histogram (OVH) features between PTV and other organs at risk. The full dataset was separated into two parts; a training dataset and a validation dataset. The prediction outcomes were the MHD and MLD. The spearman’s rank correlation coefficient was used to evaluate the correlation between the anatomical features and dosimetric features. The stepwise multiple regression method was used to fit the PF. The cross validation method was used to evaluate the model. Results: With 1000 repetitions, the mean prediction error of the MHD was 469 cGy. The most correlated factor was the first principal components of the OVH between heart and PTV and the overlap between heart and PTV in Z-axis. The mean prediction error of the MLD was 284 cGy. The most correlated factors were the first principal components of the OVH between heart and PTV and the overlap between lung and PTV in Z-axis. Conclusions: It is feasible to use patients’ anatomic and dosimetric features to generate a predicted Pareto front. Additional samples and further studies are required improve the prediction model.« less

Quantifying the processes controlling intraseasonal mixed-layer temperature variability in the tropical Indian Ocean

NASA Astrophysics Data System (ADS)

Halkides, D. J.; Waliser, Duane E.; Lee, Tong; Menemenlis, Dimitris; Guan, Bin

2015-02-01

Spatial and temporal variation of processes that determine ocean mixed-layer (ML) temperature (MLT) variability on the timescale of the Madden-Julian Oscillation (MJO) in the Tropical Indian Ocean (TIO) are examined in a heat-conserving ocean state estimate for years 1993-2011. We introduce a new metric for representing spatial variability of the relative importance of processes. In general, horizontal advection is most important at the Equator. Subsurface processes and surface heat flux are more important away from the Equator, with surface heat flux being the more dominant factor. Analyses at key sites are discussed in the context of local dynamics and literature. At 0°, 80.5°E, for MLT events > 2 standard deviations, ocean dynamics account for more than two thirds of the net tendency during cooling and warming phases. Zonal advection alone accounts for ˜40% of the net tendency. Moderate events (1-2 standard deviations) show more differences between events, and some are dominated by surface heat flux. At 8°S, 67°E in the Seychelles-Chagos Thermocline Ridge (SCTR) area, surface heat flux accounts for ˜70% of the tendency during strong cooling and warming phases; subsurface processes linked to ML depth (MLD) deepening (shoaling) during cooling (warming) account for ˜30%. MLT is more sensitive to subsurface processes in the SCTR, due to the thin MLD, thin barrier layer and raised thermocline. Results for 8°S, 67°E support assertions by Vialard et al. (2008) not previously confirmed due to measurement error that prevented budget closure and the small number of events studied. The roles of MLD, barrier layer thickness, and thermocline depth on different timescales are examined.

SU-E-T-125: Application of Jaw-Tracking Function in VMAT for Upper Thoracic Esophageal Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, W; Chen, J; Zhai, T

2015-06-15

Purpose: To explore the effect of the Jaw-tracking with RapidArc(JT-RapidArc) plans for upper thoracic esophageal cancer. Methods: Treatment planning was designed by using RapidArc and JT-RapidArc techniques for 11 consecutive patients. The dose-volume histogram parameters of PTV and the organs at risk(OAR), conformity index(CI), heterogeneity index(HI), low dose volume of normal tissue(B-P) and monitor units(MUs) were compared between the different techniques. Results: JT-RapidArc plans provided the better coverage of PTV1(64) D98 and HI(P<0.05), lower MLD, D2 of PTV1(64) and PTV2(54), but no statistically difference in CI(P>0.05), which comparison with RapidArc plans. Plans with JT- RapidArc had lower Lung of V5,more » V10, V13, V20, V30, MLD(P<0.05); heart of V20, MLD(P<0.05); and B-P of V5, V10, V15, V20, V30(P<0.05); but no significantly different in Spinal cord and SC-PRV as compared with RapidArc plans. JT-RapidArc plans increaseed the MUs by 1%(P>0.05) as compared with RapidArc plans. Conclusion: All of the plans had met the requirements of clinical dosimetry. JT-RapidArc plans as compared with RapidArc plans, showing better part of target coverage, part of OARS(lung and heart) and heart and B-P sparing, which MUs was slightly increased. This work was sponsored by Shantou University Medical College Clinical Research Enhancement Initiative(NO.201424)« less

Associations among attitudes, perceived difficulty of learning science, gender, parents' occupation and students' scientific competencies

NASA Astrophysics Data System (ADS)

Chi, ShaoHui; Wang, Zuhao; Liu, Xiufeng; Zhu, Lei

2017-11-01

This study investigated the associations among students' attitudes towards science, students' perceived difficulty of learning science, gender, parents' occupations and their scientific competencies. A sample of 1591 (720 males and 871 females) ninth-grade students from 29 junior high schools in Shanghai completed a scientific competency test and a Likert scale questionnaire. Multiple regression analysis revealed that students' general interest of science, their parents' occupations and perceived difficulty of science significantly associated with their scientific competencies. However, there was no gender gap in terms of scientific competencies.

Typically Developing Children's Understanding of and Attitudes towards Diversity and Peers with Learning Difficulties in the Greek Setting

ERIC Educational Resources Information Center

Ralli, A. M.; Margeti, M.; Doudoni, E.; Pantelemidou, V.; Rozou, T.; Evaggelopoulou, E.

2011-01-01

During the last few years, across Europe, special education has been orientated towards an inclusive model. Accordingly, in Greece, special education functions as an integral part of general education. However, few studies have investigated how children in the mainstream school understand diversity issues and specifically learning difficulties.…

Survey of Complementary and Alternative Therapies Used by Children with Specific Learning Difficulties (Dyslexia)

ERIC Educational Resources Information Center

Bull, Leona

2009-01-01

Background: Dyslexia is a common learning difficulty affecting up to 10% of British children that is associated with a wide range of cognitive, emotional and physical symptoms. In the absence of effective conventional treatment, it is likely that parents will seek complementary and alternative medicine (CAM) to try and help their children.…

Prevalence and Pattern of Learning Difficulties in Primary School Students in Jordan

ERIC Educational Resources Information Center

Abu-Hamour, Bashir; Al-Hmouz, Hanan

2016-01-01

The major purpose of this study was to investigate the prevalence of learning difficulties (LDs) among primary school students (Grade 1 to Grade 3) in Jordan. A total of 306 students were randomly selected and tested using the Arabic version of the Woodcock-Johnson Basic Achievement Tests that measure reading, spelling, and calculation skills. The…

Hands-On Tabletop Units for Addressing Persistent Conceptual Difficulties in Continuity and Frictional Loss in Fluid Mechanics

ERIC Educational Resources Information Center

Li, Xuesong; Van Wie, Bernard J.

2016-01-01

The difficulty in covering chemical engineering concepts using traditional lectures and whiteboard teaching approaches means today's students' learning demands are unfulfilled, so alternate methods are needed. Desktop learning modules (DLMs) are designed to show industrial fluid flow and heat transfer concepts in a standard classroom so students…

A Comparative Study of Teachers' Pedagogical Competencies in Supporting Children with Learning Difficulties in Primary Schools in Ghana and Brunei Darussalam

ERIC Educational Resources Information Center

Abosi, Okechukwu; Alhassan, Abdul Razak Kuyini

2017-01-01

Teachers' pedagogical competencies level is increasingly affecting the implementation of inclusive education policy in many countries. The aimed at comparing primary school teachers' competence levels in supporting children with learning difficulties in Brunei Darussalam and Ghana. Descriptive survey design was used and 188 primary school teachers…

Formative Assessment Pre-Test to Identify College Students' Prior Knowledge, Misconceptions and Learning Difficulties in Biology

ERIC Educational Resources Information Center

Lazarowitz, Reuven; Lieb, Carl

2006-01-01

A formative assessment pretest was administered to undergraduate students at the beginning of a science course in order to find out their prior knowledge, misconceptions and learning difficulties on the topic of the human respiratory system and energy issues. Those findings could provide their instructors with the valuable information required in…

A Comparison of Saudi and Canadian Children's Knowledge of the Causes of Learning Difficulties

ERIC Educational Resources Information Center

Felimban, Huda; Nowicki, Elizabeth A.; Dare, Lynn; Brown, Jason

2016-01-01

In this comparative study, students from inclusive schools in Canada and Saudi Arabia shared their beliefs about factors associated with learning difficulties. Qualitative data were collected through interviews with 36 Canadian and 62 Saudi elementary students in Grades 5 and 6. Thematic analysis uncovered six themes: lack of knowledge,…

Educating Children and Young People with Fetal Alcohol Spectrum Disorders: Constructing Personalised Pathways to Learning

ERIC Educational Resources Information Center

Blackburn, Carolyn; Carpenter, Barry; Egerton, Jo

2012-01-01

The range of learning difficulties associated with children and young people who have Fetal Alcohol Spectrum Disorders (FASD) has been highlighted as an emerging but little understood area of Special Educational Needs. This engaging, timely and highly practical book will raise awareness about FASD and its associated difficulties across the entire…

Awareness of Number In Children With Severe And Profound Learning Difficulties: Three Exploratory Case Studies

ERIC Educational Resources Information Center

Porter, Jill

2005-01-01

This paper reports on exploratory work investigating how children with severe and profound learning difficulties register an awareness of small quantities and how they might use this information to inform their understanding. It draws on studies of typically developing children and investigates their application to pupils whose response to…

Learning Difficulties and Ethnicity: Updating a Framework for Action

ERIC Educational Resources Information Center

Poxton, Richard

2012-01-01

This update of the Framework for Action highlights the continuing relevance of its message as well as those raised by Valuing People Now. People with learning difficulties and their families from Black and minority ethnic (BME) communities have been highlighted as a priority group by Valuing People since 2001 and remain a priority for better…

Naming Abilities in Low-Proficiency Second Language Learners

ERIC Educational Resources Information Center

Borodkin, Katy; Faust, Miriam

2014-01-01

Difficulties in second language (L2) learning are often associated with recognizable learning difficulties in native language (L1), such as in dyslexia. However, some individuals have low L2 proficiency but intact L1 reading skills. These L2 learners experience frequent tip-of-the-tongue states while naming in L1, which indicates that they have a…

A Review of Teaching Sentence-Level Writing Skills to Students with Writing Difficulties and Learning Disabilities

ERIC Educational Resources Information Center

Datchuk, Shawn M.; Kubina, Richard M.

2013-01-01

Students with writing difficulties and learning disabilities struggle with many aspects of the writing process, including use of sentence-level skills. This literature review summarizes results from 19 published articles that used single-case or group-experimental and quasi-experimental designs to investigate effects of intervention on the…

A Preliminary Instrument for Measuring Students' Subjective Perceptions of Difficulties in Learning Recursion

ERIC Educational Resources Information Center

Lacave, Carmen; Molina, Ana I.; Redondo, Miguel A.

2018-01-01

Contribution: Findings are provided from an initial survey to evaluate the magnitude of the recursion problem from the student point of view. Background: A major difficulty that programming students must overcome--the learning of recursion--has been addressed by many authors, using various approaches, but none have considered how students perceive…

Comparison of Scores on Two Visual-Motor Tests for Children Referred for Learning or Adjustment Difficulties.

ERIC Educational Resources Information Center

DeMers, Stephen T.; And Others

1981-01-01

This study compared the performance of school-aged children referred for learning or adjustment difficulties on Beery's Developmental Test of Visual-Motor Integration and Koppitz's version of the Bender-Gestalt test. Results indicated that the tests are related but not equivalent when administered to referred populations. (Author/AL)

How Does the Legal System Respond when Children with Learning Difficulties Are Victimized?

ERIC Educational Resources Information Center

Cederborg, Ann-Christin; Lamb, Michael E.

2006-01-01

Objective: To understand how the Swedish legal system perceives and handles mentally handicapped children who may have been victimized. Method: Twenty-two judicial districts in Sweden provided complete files on 39 District Court cases (including the Appeals Court files on 17 of these cases) involving children with learning difficulties or other…

Initial Considerations for Helping Your Infant Learn To Eat [and] Strategies To Promote Oral Eating in Infants.

ERIC Educational Resources Information Center

Pagano, John

These two papers offer parents of infants and toddlers with developmental disabilities and feeding problems both general advice and specific intervention strategies. The first paper examines the causes of feeding difficulty (such as a physical structure problem, fear of eating, or difficulty learning to eat); the need for intervention while…

Children Placed at Risk for Learning and Behavioral Difficulties: Implementing a School-Wide System of Early Identification and Intervention.

ERIC Educational Resources Information Center

O'Shaughnessy, Tam E.; Lane, Kathleen L.; Gresham, Frank M.; Beebe-Frankenberger, Margaret E.

2003-01-01

This article describes a school-wide system of early identification and intervention for children recognized as being at risk for learning and behavior difficulties. Suggested guidelines for implementing such a program include: evaluating existing theory, knowledge, and practice; providing ongoing professional development; creating a school-wide…

An Examination of the Relationship among Teachers' Perceptions of Social-Emotional Learning, Teaching Efficacy, Teacher-Student Interactions, and Students' Behavioral Difficulties

ERIC Educational Resources Information Center

Poulou, Maria S.

2017-01-01

The study investigated how teachers' perceptions of emotional intelligence (EI), social and emotional learning (SEL) skills, and teaching efficacy relate to perceptions of teacher-student relationships and students' emotional and behavioral difficulties. Ninety-eight elementary teachers from public schools in central Greece completed the…

Perry's Scheme of Intellectual and Epistemological Development as a Framework for Describing Student Difficulties in Learning Organic Chemistry

ERIC Educational Resources Information Center

Grove, Nathaniel P.; Bretz, Stacey Lowery

2010-01-01

We have investigated student difficulties with the learning of organic chemistry. Using Perry's Model of Intellectual Development as a framework revealed that organic chemistry students who function as dualistic thinkers struggle with the complexity of the subject matter. Understanding substitution/elimination reactions and multi-step syntheses is…

Fraction Intervention for Students with Mathematics Difficulties: Lessons Learned from Five Randomized Controlled Trials

ERIC Educational Resources Information Center

Fuchs, Lynn S.; Malone, Amelia S.; Schumacher, Robin F.; Namkung, Jessica; Wang, Amber

2017-01-01

In this article, the authors summarize results from 5 randomized controlled trials assessing the effects of intervention to improve the fraction performance of fourth-grade students at risk for difficulty in learning about fractions. The authors begin by explaining the importance of competence with fractions and why an instructional focus on…

Difficulties in Academic Writing: From the Perspective of King Saud University Postgraduate Students

ERIC Educational Resources Information Center

Al Fadda, Hind

2012-01-01

The purpose of this study was to determine what difficulties King Saud University students encounter when learning to write academic English and to differentiate between students' learning needs and objectives. The sample consisted of 50 postgraduate students enrolled in King Saud University during the academic year 2009-2010. Analysis of the data…

Considerations of Numbers Used in Tasks for Promoting Multiplicative Reasoning in Students with Learning Difficulties in Mathematics

ERIC Educational Resources Information Center

Risley, Rachael Ann

2016-01-01

This study explored the impact of numbers used in instructional tasks on the construction and generalization of multiplicative reasoning by fourth grade students designated as having learning difficulties or disabilities in mathematics (SLDs). In particular, this study addressed the following research questions: (1) In what ways do SLDs'…

Inclusive Education for Children with Specific Learning Difficulties: Analysis of Opportunities and Barriers in Inclusive Education in Slovenia

ERIC Educational Resources Information Center

Kavkler, Marija; Babuder, Milena Košak; Magajna, Lidija

2015-01-01

Inclusive education allows for universal inclusion, participation and achievement of all children, including children with specific learning difficulties (SpLD). Children with SpLD form a heterogeneous group with diverse cognitive deficits, special educational needs (SEN) and strengths, and have a legislated right to the continuum of both…

Emergence, Learning Difficulties, and Misconceptions in Chemistry Undergraduate Students' Conceptualizations of Acid Strength

ERIC Educational Resources Information Center

Tümay, Halil

2016-01-01

Philosophical debates about chemistry have clarified that the issue of emergence plays a critical role in the epistemology and ontology of chemistry. In this article, it is argued that the issue of emergence has also significant implications for understanding learning difficulties and finding ways of addressing them in chemistry. Particularly, it…

Associations among Attitudes, Perceived Difficulty of Learning Science, Gender, Parents' Occupation and Students' Scientific Competencies

ERIC Educational Resources Information Center

Chi, ShaoHui; Wang, Zuhao; Liu, Xiufeng; Zhu, Lei

2017-01-01

This study investigated the associations among students' attitudes towards science, students' perceived difficulty of learning science, gender, parents' occupations and their scientific competencies. A sample of 1591 (720 males and 871 females) ninth-grade students from 29 junior high schools in Shanghai completed a scientific competency test and…

A School-Based Movement Programme for Children with Motor Learning Difficulty

ERIC Educational Resources Information Center

Mannisto, Juha-Pekka; Cantell, Marja; Huovinen, Tommi; Kooistra, Libbe; Larkin, Dawne

2006-01-01

The study investigated the effectiveness of a school-based movement programme for a population of 5 to 7 year old children. Performance profiles on the Movement ABC were used to classify the children and to assess skill changes over time. Children were assigned to four different groups: motor learning difficulty (n = 10), borderline motor learning…

Development and Validation of Curriculum-Based Measurement (CBM) for Identifying Students with Reading Difficulties

ERIC Educational Resources Information Center

Valladolid, Violeta C.

2015-01-01

The role of classroom teachers in the early detection of learning difficulty/disability in school children cannot be ignored. When it comes to young children's literacy learning, there is substantial consensus that the teacher is the primary assessment agent (Johnston & Rogers, 2002). But classroom teachers also have a lot of responsibilities…

Difference and Choice: Exploring Prenatal Testing and the Use of Genetic Information with People with Learning Difficulties.

ERIC Educational Resources Information Center

Ward, Linda; Howarth, Joyce; Rodgers, Jackie

2002-01-01

This article describes two workshops that explained the use of prenatal testing and genetic information to inform choices in pregnancy to people with learning difficulties, explored the issues with them, and describe the contribution subsequently made by these people to a British national conference on this subject. (Contains references.)…

Student Difficulties in Learning Density: A Distributed Cognition Perspective

ERIC Educational Resources Information Center

Xu, Lihua; Clarke, David

2012-01-01

Density has been reported as one of the most difficult concepts for secondary school students (e.g. Smith et al. 1997). Discussion about the difficulties of learning this concept has been largely focused on the complexity of the concept itself or student misconceptions. Few, if any, have investigated how the concept of density was constituted in…

Learning Difficulties and the Power of Labelling in ABE. Mendip Papers MP071.

ERIC Educational Resources Information Center

Bergin, Sue; Johnson, Andy

A study examined recent developments in adult basic education (ABE) in Great Britain in relation to students with learning difficulties and issues about the ways in which programs seemed to be moving. Information was collected from ABE staff and students in case study sites in northwest England from the following sources: semistructured interviews…

Performance of Children with Developmental Dyslexia on Two Skill Learning Tasks--Serial Reaction Time and Tower of Hanoi Puzzle

ERIC Educational Resources Information Center

Vakil, Eli; Lowe, Michal; Goldfus, Carol

2015-01-01

Among the various theories proposed to explain developmental dyslexia (DD), the theory of specific procedural learning difficulties has gained certain support and is the framework for the current research. This theory claims that an inability to achieve skill automaticity explains the difficulties experienced by individuals with DD. Previous…

Do Learning Difficulties Differentiate Elementary Teachers' Attributional Patterns for Students' Academic Failure? A Comparison between Greek Regular and Special Education Teachers

ERIC Educational Resources Information Center

Vlachou, Anastasia; Eleftheriadou, Dimitra; Metallidou, Panayiota

2014-01-01

This study aimed to (a) investigate whether the presence of learning difficulties (LD) in primary school children differentiates Greek teachers' attributional patterns, emotional responses, expectations and evaluative feedback for the children's academic failures and (b) to examine possible differences between regular and special education…

Ethnic & Linguistic Minority Children with Special Needs. A Critical Review of Educational Language & Culture.

ERIC Educational Resources Information Center

Miles, Christine

This paper describes experiences in teaching ethnic and linguistic minority children with learning difficulties and counseling their families, from 1976 to 1992 in Pakistan and England. The paper begins with a vignette describing an ethnic minority child with learning difficulties. A global approach to the issues is then presented, examining the…

Children's Structured Conceptualizations of Their Beliefs on the Causes of Learning Difficulties

ERIC Educational Resources Information Center

Nowicki, Elizabeth A.; Brown, Jason; Stepien, Magdalena

2014-01-01

Elementary school children between 9 and 12 years of age were interviewed on what they believed to be the causes of learning difficulties and were invited to take part in the analysis of the data. We achieved this with Trochim's concept mapping approach that combines qualitative and quantitative data analyses. Study results indicated that children…

Real Power? An Examination of the Involvement of People with Learning Difficulties in Strategic Service Development in Cambridgeshire

ERIC Educational Resources Information Center

Dearden-Phillips, Craig; Fountain, Rob

2005-01-01

Securing meaningful involvement in service development and provision can be seen as a particular challenge for people with learning difficulties. The National Health Service & Community Care Act [(1990) HMSO, ISBN 0105419907] and more recently Valuing People [Department of Health (2001) "Valuing people: a new strategy for learning…

Conservative interventions for preventing clinically detectable upper-limb lymphoedema in patients who are at risk of developing lymphoedema after breast cancer therapy.

PubMed

Stuiver, Martijn M; ten Tusscher, Marieke R; Agasi-Idenburg, Carla S; Lucas, Cees; Aaronson, Neil K; Bossuyt, Patrick M M

2015-02-13

Breast cancer-related lymphoedema can be a debilitating long-term sequela of breast cancer treatment. Several studies have investigated the effectiveness of different treatment strategies to reduce the risk of breast cancer-related lymphoedema. To assess the effects of conservative (non-surgical and non-pharmacological) interventions for preventing clinically-detectable upper-limb lymphoedema after breast cancer treatment. We searched the Cochrane Breast Cancer Group's (CBCG) Specialised Register, CENTRAL, MEDLINE, EMBASE, CINAHL, PEDro, PsycINFO, and the World Health Organization (WHO) International Clinical Trials Registry Platform in May 2013. Reference lists of included trials and other systematic reviews were searched. Randomised controlled trials that reported lymphoedema as the primary outcome and compared any conservative intervention to either no intervention or to another conservative intervention. Three authors independently assessed the risk of bias and extracted data. Outcome measures included lymphoedema, infection, range of motion of the shoulder, pain, psychosocial morbidity, level of functioning in activities of daily life (ADL), and health-related quality of life (HRQoL). Where possible, meta-analyses were performed. Risk ratio (RRs) or hazard ratio (HRs) were reported for dichotomous outcomes or lymphoedema incidence, and mean differences (MDs) for range of motion and patient-reported outcomes. Ten trials involving 1205 participants were included. The duration of patient follow-up ranged from 2 days to 2 years after the intervention. Overall, the quality of the evidence generated by these trials was low, due to risk of bias in the included trials and inconsistency in the results. Manual lymph drainageIn total, four studies used manual lymph drainage (MLD) in combination with usual care or other interventions. In one study, lymphoedema incidence was lower in patients receiving MLD and usual care (consisting of standard education or exercise, or both) compared to usual care alone. A second study reported no difference in lymphoedema incidence when MLD was combined with physiotherapy and education compared to physiotherapy alone. Two other studies combining MLD with compression and scar massage or exercise observed a reduction in lymphoedema incidence compared to education only, although this was not significant in one of the studies. Two out of the four studies reported on shoulder mobility where MLD combined with exercise gave better shoulder mobility for lateral arm movement (shoulder abduction) and forward flexion in the first weeks after breast cancer surgery, compared to education only (mean difference for abduction 22°; 95% confidence interval (CI) 14 to 30; mean difference for forward flexion 14°; 95% CI 7 to 22). Two of the studies on MLD reported on pain, with inconsistent results. Results on HRQoL in two studies on MLD were also contradictory. Exercise: early versus delayed start of shoulder mobilising exercisesThree studies examined early versus late start of postoperative shoulder exercises. The pooled relative risk of lymphoedema after an early start of exercises was 1.69 (95% CI 0.94 to 3.01, 3 studies, 378 participants). Shoulder forward flexion was better at one and six months follow-up for participants who started early with mobilisation exercises compared to a delayed start (two studies), but no meta-analysis could be performed due to statistical heterogeneity. There was no difference in shoulder mobility or self-reported shoulder disability at 12 months follow-up (one study). One study evaluated HRQoL and reported difference at one year follow-up (mean difference 1.6 points, 95% CI -2.14 to 5.34, on the Trial Outcome Index of the FACT-B). Two studies collected data on wound drainage volumes and only one study reported higher wound drainage volumes in the early exercise group. Exercise: resistance trainingTwo studies compared progressive resistance training to restricted activity. Resistance training after breast cancer treatment did not increase the risk of developing lymphoedema (RR 0.58; 95% CI 0.30 to 1.13, two studies, 358 participants) provided that symptoms are monitored and treated immediately if they occur. One out of the two studies measured pain where participants in the resistance training group reported pain more often at three months and six months compared to the control group. One study reported HRQoL and found no significant difference between the groups. Patient education, monitoring and early interventionOne study investigated the effects of a comprehensive outpatient follow-up programme, consisting of patient education, exercise, monitoring of lymphoedema symptoms and early intervention for lymphoedema, compared to education alone. Lymphoedema incidence was lower in the comprehensive outpatient follow-up programme (at any time point) compared to education alone (65 people). Participants in the outpatient follow-up programme had a significantly faster recovery of shoulder abduction compared to the education alone group. Based on the current available evidence, we cannot draw firm conclusions about the effectiveness of interventions containing MLD. The evidence does not indicate a higher risk of lymphoedema when starting shoulder-mobilising exercises early after surgery compared to a delayed start (i.e. seven days after surgery). Shoulder mobility (that is, lateral arm movements and forward flexion) is better in the short term when starting shoulder exercises earlier compared to later. The evidence suggests that progressive resistance exercise therapy does not increase the risk of developing lymphoedema, provided that symptoms are closely monitored and adequately treated if they occur.Given the degree of heterogeneity encountered, limited precision, and the risk of bias across the included studies, the results of this review should be interpreted with caution.

Phase I/II Pilot Study of Mixed Chimerism to Treat Inherited Metabolic Disorders

ClinicalTrials.gov

2017-11-15

Hurler Syndrome (MPS I); Hurler-Scheie Syndrome; Hunter Syndrome (MPS II); Sanfilippo Syndrome (MPS III); Krabbe Disease (Globoid Leukodystrophy); Metachromatic Leukodystrophy (MLD); Adrenoleukodystrophy (ALD and AMN); Sandhoff Disease; Tay Sachs Disease; Pelizaeus Merzbacher (PMD); Niemann-Pick Disease; Alpha-mannosidosis

Conformal and highly luminescent monolayers of Alq3 prepared by gas-phase molecular layer deposition.

PubMed

Räupke, André; Albrecht, Fabian; Maibach, Julia; Behrendt, Andreas; Polywka, Andreas; Heiderhoff, Ralf; Helzel, Jonatan; Rabe, Torsten; Johannes, Hans-Hermann; Kowalsky, Wolfgang; Mankel, Eric; Mayer, Thomas; Görrn, Patrick; Riedl, Thomas

2014-01-22

The gas-phase molecular layer deposition (MLD) of conformal and highly luminescent monolayers of tris(8-hydroxyquinolinato)aluminum (Alq3) is reported. The controlled formation of Alq3 monolayers is achieved for the first time by functionalization of the substrate with amino groups, which serve as initial docking sites for trimethyl aluminum (TMA) molecules binding datively to the amine. Thereby, upon exposure to 8-hydroxyquinoline (8-HQ), the self-limiting formation of highly luminescent Alq3 monolayers is afforded. The growth process and monolayer formation were studied and verified by in situ quartz crystal monitoring, optical emission and absorption spectroscopy, and X-ray photoelectron spectroscopy. The nature of the MLD process provides an avenue to coat arbitrarily shaped 3D surfaces and porous structures with high surface areas, as demonstrated in this work for silica aerogels. The concept presented here paves the way to highly sensitive luminescent sensors and dye-sensitized metal oxides for future applications (e.g., in photocatalysis and solar cells).

Mid-Latitude Disturbances - Triggered by Hurricane Dennis?

NASA Astrophysics Data System (ADS)

Earle, G. D.; Bishop, R. L.

2001-05-01

Midlatitude irregularities in F-region electron density have been previously observed in-situ by the Atmosphere Explorer-E satellite [Hanson and Johnson, 1992]. These authors noted the similarity of the irregularities to equatorial spread-F, which is commonly observed at much lower latitudes (within 20 degrees of the magnetic equator). They coined the term midlatitude disturbances (MLDs), and postulated that the irregularities resulted from the Perkins instability in a region where the east-west velocities of the ions differs from that of the neutrals. We present ionosonde observations of range spread-F made over Wallops Island, VA that may show signatures of similar MLD events. The data show evidence of an apparent correlation between the occurrence of the irregularities and the passage of hurricane Dennis over the magnetic meridian of Wallops Island. Based on this evidence, we examine the possibility that the Perkins instability and/or MLD events can be triggered by gravity waves spawned by the hurricane. Reference: Hanson, W.B., and F.S. Johnson, Planet. Space Sci., vol. 40, pp. 1615-1630, 1992.

Ancient Continental Lithosphere Dislocated Beneath Ocean Basins Along the Mid-Lithosphere Discontinuity: A Hypothesis

NASA Astrophysics Data System (ADS)

Wang, Zhensheng; Kusky, Timothy M.; Capitanio, Fabio A.

2017-09-01

The documented occurrence of ancient continental cratonic roots beneath several oceanic basins remains poorly explained by the plate tectonic paradigm. These roots are found beneath some ocean-continent boundaries, on the trailing sides of some continents, extending for hundreds of kilometers or farther into oceanic basins. We postulate that these cratonic roots were left behind during plate motion, by differential shearing along the seismically imaged mid-lithosphere discontinuity (MLD), and then emplaced beneath the ocean-continent boundary. Here we use numerical models of cratons with realistic crustal rheologies drifting at observed plate velocities to support the idea that the mid-lithosphere weak layer fostered the decoupling and offset of the African continent's buoyant cratonic root, which was left behind during Meso-Cenozoic continental drift and emplaced beneath the Atlantic Ocean. We show that in some cratonic areas, the MLD plays a similar role as the lithosphere-asthenosphere boundary for accommodating lateral plate tectonic displacements.

Similarity is not enough: Tipping points of Ebola Zaire mortalities

NASA Astrophysics Data System (ADS)

Phillips, J. C.

2015-06-01

In early 2014 an outbreak of a slightly mutated Zaire Ebola subtype appeared in West Africa which is less virulent than 1976 and 1994 strains. The numbers of cases per year appear to be ∼1000 times larger than the earlier strains, suggesting a greatly enhanced transmissibility. Although the fraction of the 2014 spike glycoprotein mutations is very small (∼3%), the mortality is significantly reduced, while the transmission appears to have increased strongly. Bioinformatic scaling had previously shown similar inversely correlated trends in virulence and transmission in N1 (H1N1) and N2 (H3N2) influenza spike glycoprotein mutations. These trends appear to be related to various external factors (migration, availability of pure water, and vaccination programs). The molecular mechanisms for Ebola's mutational response involve mainly changes in the disordered mucin-like domain (MLD) of its spike glycoprotein amino acids. The MLD has been observed to form the tip of an oligomeric amphiphilic wedge that selectively pries apart cell-cell interfaces via an oxidative mechanism.

Associated factors of radiation pneumonitis induced by precise radiotherapy in 186 elderly patients with esophageal cancer.

PubMed

Cui, Zhen; Tian, Ye; He, Bin; Li, Hongwei; Li, Duojie; Liu, Jingjing; Cai, Hanfei; Lou, Jianjun; Jiang, Hao; Shen, Xueming; Peng, Kaigui

2015-01-01

Radiation pneumonitis is one of the most severe complications of esophageal cancer. To explore the factors correlated to radiation pneumonitis induced by precise radiotherapy for elderly patients with esophageal cancer. The retrospective analysis was used to collect clinical data from 186 elderly patients with esophageal cancer. The incidence of radiation pneumonitis was observed, followed by statistical analysis through ANVON or multiple regression analysis. 27 in 186 cases of esophageal cancer suffered from radiation pneumonitis, with incidence of 14.52%. The single factor analysis showed that, Karnofsky performance status (KPS) score, chronic obstructive pulmonary disease, concurrent chemoradiotherapy, gross tumor volume (GTV) dose, lung V20, mean lung dose (MLD) and planning target volume (PTV) were associated with radiation pneumonitis. The logistic regression analysis indicated that, concurrent chemoradiotherapy, GTV dose, lung V20 and PTV were the independent factors of radiation pneumonitis. The concurrent chemoradiotherapy, GTV dose, lung V20, MLD and PTV are the major risk factors of radiation pneumonitis for elderly patients with esophageal cancer.

Hybrid Model Predictive Control for Sequential Decision Policies in Adaptive Behavioral Interventions.

PubMed

Dong, Yuwen; Deshpande, Sunil; Rivera, Daniel E; Downs, Danielle S; Savage, Jennifer S

2014-06-01

Control engineering offers a systematic and efficient method to optimize the effectiveness of individually tailored treatment and prevention policies known as adaptive or "just-in-time" behavioral interventions. The nature of these interventions requires assigning dosages at categorical levels, which has been addressed in prior work using Mixed Logical Dynamical (MLD)-based hybrid model predictive control (HMPC) schemes. However, certain requirements of adaptive behavioral interventions that involve sequential decision making have not been comprehensively explored in the literature. This paper presents an extension of the traditional MLD framework for HMPC by representing the requirements of sequential decision policies as mixed-integer linear constraints. This is accomplished with user-specified dosage sequence tables, manipulation of one input at a time, and a switching time strategy for assigning dosages at time intervals less frequent than the measurement sampling interval. A model developed for a gestational weight gain (GWG) intervention is used to illustrate the generation of these sequential decision policies and their effectiveness for implementing adaptive behavioral interventions involving multiple components.

Can Multiple-Choice Testing Induce Desirable Difficulties? Evidence from the Laboratory and the Classroom.

PubMed

Bjork, Elizabeth Ligon; Soderstrom, Nicholas C; Little, Jeri L

2015-01-01

The term desirable difficulties (Bjork, 1994) refers to conditions of learning that, though often appearing to cause difficulties for the learner and to slow down the process of acquisition, actually improve long-term retention and transfer. One known desirable difficulty is testing (as compared with restudy), although typically it is tests that clearly involve retrieval--such as free and cued recall tests--that are thought to induce these learning benefits and not multiple-choice tests. Nonetheless, multiple-choice testing is ubiquitous in educational settings and many other high-stakes situations. In this article, we discuss research, in both the laboratory and the classroom, exploring whether multiple-choice testing can also be fashioned to promote the type of retrieval processes known to improve learning, and we speculate about the necessary properties that multiple-choice questions must possess, as well as the metacognitive strategy students need to use in answering such questions, to achieve this goal.

Keeping Wartime Memory Alive: An Oral History Project about the Wartime Memories of People with Learning Difficulties in Cumbria

ERIC Educational Resources Information Center

Dias, John; Eardley, Malcolm; Harkness, Elizabeth; Townson, Louise; Brownlee-Chapman, Chloe; Chapman, Rohhss

2012-01-01

This article discusses an oral history project funded by the Heritage Lottery. It recorded the memories of eight people with learning difficulties during the Second World War in Cumbria, UK, before their personal histories were lost forever. This qualitative, inclusive research project was supported by various organisations. The process of…

Effects on Reading of an Early Intervention Program for Children at Risk of Learning Difficulties

ERIC Educational Resources Information Center

González-Valenzuela, María-José; Martín-Ruiz, Isaías

2017-01-01

The study aimed to analyze the effects on reading of an early oral and written language intervention program for Spanish children at risk of learning difficulties. The goal of this classroom-based program was to prioritize a systematic approach to reading and writing and to foster phonological knowledge and the development of oral language…

The Value of Using ICT in the Education of School Students with Learning Difficulties

ERIC Educational Resources Information Center

Adam, Tas; Tatnall, Arthur

2017-01-01

This article argues that whatever the 2015 OECD report says about the value of ICT in relation to PISA results, our research has shown that using ICT in the education of students with Learning Difficulties has great value in interesting, enthusing and inspiring these students, so leading to better educational outcomes. The term "Learning…

Succeeding against the Odds: Observations on Coping by Three Intellectually Very Able University Students with Specific Learning Difficulties in Hong Kong

ERIC Educational Resources Information Center

Lo, Cecilia C.; Yuen, Mantak

2017-01-01

This small-scale exploratory study identified strategies used by three intellectually very able university students with specific learning difficulties for maintaining motivation on their path to achievement. All three participants were located in Hong Kong. The research questions were: (a) What coping strategies are used by intellectually very…

Primary School Teachers' Practices and Troubles with the Students Who They Think Have Undiagnosed Difficulties in Verbal Communication, Reading and Writing

ERIC Educational Resources Information Center

Ergen, Yusuf; Elma, Cevat

2018-01-01

The primary school Turkish program was basically built on three learning domains. These are the learning domains of verbal communication, reading and writing. The purpose of the present study is to determine primary school teachers' practices and difficulties related to students considered to have undiognosed verbal communication, reading and…

Enhancing Peer Acceptance of Children with Learning Difficulties: Classroom Goal Orientation and Effects of a Storytelling Programme with Drama Techniques

ERIC Educational Resources Information Center

Law, Yin-kum; Lam, Shui-fong; Law, Wilbert; Tam, Zoe W. Y.

2017-01-01

Peer acceptance is an important facilitator for the success of inclusive education. The aim of the current study is twofold: (1) to examine how classroom goal orientation is associated with children's acceptance of peers with learning difficulties; and (2) to evaluate the effectiveness of a storytelling programme with drama techniques on…

To What Extent Does Information and Communication Technology Support Inclusion in Education of Students with Learning Difficulties?

ERIC Educational Resources Information Center

Mølster, Terje; Nes, Kari

2018-01-01

The main intention of this study is to explore the relationship between information and communication technology (ICT) and inclusion. The target group is students who are conceived as having learning difficulties or special educational needs. To illuminate this issue, we draw on data collected in a recent national research project about the…

Fraction Intervention for Students with Mathematics Difficulties: Lessons Learned from Five Randomized Control Trials

ERIC Educational Resources Information Center

Fuchs, Lynn S.; Malone, Amelia S.; Schumacher, Robin F.; Namkung, Jessica; Wang, Amber

2016-01-01

The purpose of this article was to summarize results from 5 randomized control trials assessing the effects of intervention to improve the fraction performance of 4th-grade students at-risk for difficulty in learning about fractions. We begin by explaining the importance of competence with fractions and why an instructional focus on fractions…

Self-Reported Substance Use among High School Students with and without Learning Difficulties

ERIC Educational Resources Information Center

Carroll, Annemaree; Houghton, Stephen; Bourgeois, Amanda

2014-01-01

A total of 197 Year 9 and 10 students, 74 of whom had learning difficulties (LD), from two high schools in Brisbane, the capital city of Queensland, Australia, self-reported their substance use. Seventeen substances, including two fictitious ones to detect over-reporting, were presented to participants for them to indicate their current usage,…

Pre-Service Science Teachers' PCK: Inconsistency of Pre-Service Teachers' Predictions and Student Learning Difficulties in Newton's Third Law

ERIC Educational Resources Information Center

Zhou, Shaona; Wang, Yanlin; Zhang, Chunbin

2016-01-01

There is widespread agreement that science learning always builds upon students' existing ideas and that science teachers should possess knowledge of learners. This study aims at investigating pre-service science teachers' knowledge of student misconceptions and difficulties, a crucial component of PCK, on Newton's Third Law. A questionnaire was…

Effect of Self-Instruction Strategy on the Achievement in Algebra of Students with Learning Difficulty in Mathematics

ERIC Educational Resources Information Center

Adani, Anthony; Eskay, Michael; Onu, Victoria

2012-01-01

This quasi-experimental study examined the effect of self-instruction strategy on the achievement in algebra of students with learning difficulty in mathematics. Two research questions and one null hypothesis were formulated to guide the study. The study adopted a non-randomized pre-test and post-test control group design with one experimental…

The Persistence and Functional Impact of English Language Difficulties Experienced by Children Learning English as an Additional Language and Monolingual Peers

ERIC Educational Resources Information Center

Whiteside, Katie E.; Norbury, Courtenay Frazier

2017-01-01

Purpose: This study explored whether a monolingual-normed English language battery could identify children with English as an additional language (EAL) who have persistent English language learning difficulties that affect functional academic attainment. Method: Children with EAL (n = 43) and monolingual English-speaking children (n = 46)…

Potential or Problem? An Investigation of Secondary School Teachers' Attributions of the Educational Outcomes of Students with Specific Learning Difficulties

ERIC Educational Resources Information Center

Woodcock, Stuart; Hitches, Elizabeth

2017-01-01

Despite strong support for inclusive education in principle, many teachers and administrators still demonstrate mixed responses to the inclusion of certain students in their classrooms. Students with specific learning difficulties (SpLD) form a large group of students in inclusive classrooms yet some provincial, state and national jurisdictions…

"Why Do I Slog through the Physics?" Understanding High School Students' Difficulties in Learning Physics

ERIC Educational Resources Information Center

Ekici, Erhan

2016-01-01

The aim of this study is to develop a valid and reliable instrument to assess why physics courses are perceived as one of the most difficult courses among high school students and to investigate the reasons why students have difficulty in learning physics through this scale. This study includes the development and validation studies of the…

Discriminating Children with Autism from Children with Learning Difficulties with an Adaptation of the Short Sensory Profile

ERIC Educational Resources Information Center

O'Brien, Justin; Tsermentseli, Stella; Cummins, Omar; Happe, Francesca; Heaton, Pamela; Spencer, Janine

2009-01-01

In this article, we examine the extent to which children with autism and children with learning difficulties can be discriminated from their responses to different patterns of sensory stimuli. Using an adapted version of the Short Sensory Profile (SSP), sensory processing was compared in 34 children with autism to 33 children with typical…

Lifelong Learning Programs of Education Faculty in Sinop: Evaluation of Participants' Problems and Worries

ERIC Educational Resources Information Center

Usakli, Hakan

2009-01-01

In this paper Lifelong Learning Program of Education Faculty in Sinop was evaluated in terms of interrelations between LLP and cultural shock. The barriers of LLP in Education Faculty in Sinop can be examined in two main parts: difficulties of finding suitable partner and students' difficulty in deciding whether to apply or not. These two main…

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

ERIC Educational Resources Information Center

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,…

Learner and Teacher Perception on Difficulties in Learning and Teaching Mathematics: Some Implications

ERIC Educational Resources Information Center

Abdul Gafoor, K.; Kurukkan, Abidha

2015-01-01

Mathematics holds a relevant and unique place in the school curriculum as it is important for a better living of the individual. But, it is known that most of the students are considering mathematics as difficult. This study examines the difficulties perceived by high school students and teachers in learning and teaching mathematics. Two hundred…

The Effect of Time on Difficulty of Learning (The Case of Problem Solving with Natural Numbers)

ERIC Educational Resources Information Center

Kaya, Deniz; Kesan, Cenk

2017-01-01

The main purpose of this study is to determine the time-dependent learning difficulty of "solving problems that require making four operations with natural numbers" of the sixth grade students. The study, adopting the scanning model, consisted of a total of 140 students, including 69 female and 71 male students at the sixth grade. Data…