The Role of Content Knowledge in Ill-Structured Problem Solving for High School Physics Students

ERIC Educational Resources Information Center

Milbourne, Jeff; Wiebe, Eric

2018-01-01

While Physics Education Research has a rich tradition of problem-solving scholarship, most of the work has focused on more traditional, well-defined problems. Less work has been done with ill-structured problems, problems that are better aligned with the engineering and design-based scenarios promoted by the Next Generation Science Standards. This…

Sorting Tasks and Vocabulary-in-Context Activities for Assessing Introductory Astronomy Understanding

NASA Astrophysics Data System (ADS)

Slater, Timothy F.; Loranz, D.; Prather, E. E.

2006-12-01

One of the most ardent challenges for astronomy teachers is to deeply and meaningfully assess students’ conceptual and quantitative understanding of astronomy topics. In an effort to uncover students’ actual understanding, members and affiliates of the Conceptual Astronomy and Physics Education Research (CAPER) Team at the University of Arizona and Truckee Meadows Community College are creating and field-testing innovative approaches to assessment. Leveraging from the highly successful work from physics education research, we are creating a series of tasks where students categorize a list describing common astronomical events or phenomenon; or vocabulary terms into context rich categories or conceptually rich sentences. These intellectually challenging tasks are being created to span the entire domain of topics in introductory astronomy for non-science majoring undergraduates. When completed, these sorting tasks and vocabulary-in-context activities will be able to be delivered via a drag-and-drop computer interface.

Large Context Problems and Their Applications to Education: Some Contemporary Examples

ERIC Educational Resources Information Center

Winchester, Ian

2006-01-01

Some 35 years ago, Gerard K. O'Neill used the large context of space travel with his undergraduate physics students. A Canadian physics teacher, Art Stinner, independently arrived at a similar notion in a more limited but, therefore, more generally useful sense, which he referred to as the "large context problem" approach. At a slightly earlier…

Investigating Students' Success in Solving and Attitudes towards Context-Rich Open-Ended Problems in Chemistry

ERIC Educational Resources Information Center

Overton, Tina L.; Potter, Nicholas M.

2011-01-01

Much research has been carried out on how students solve algorithmic and structured problems in chemistry. This study is concerned with how students solve open-ended, ill-defined problems in chemistry. Over 200 undergraduate chemistry students solved a number of open-ended problem in groups and individually. The three cognitive variables of…

Making the Most of Mobility: Virtual Mentoring and Education Practitioner Professional Development

ERIC Educational Resources Information Center

Owen, Hazel D.

2015-01-01

Learning provision, including professional learning, needs to embrace mobility (of knowledge, cultures and contexts--physical and cerebral) to enable education practitioners to interact locally and globally, engage with new literacies, access rich contexts, and to question, co-construct and collaborate. Virtual mentoring, also known as distance,…

Cognitive development in introductory physics: A research-based approach to curriculum reform

NASA Astrophysics Data System (ADS)

Teodorescu, Raluca Elena

This project describes the research on a classification of physics problems in the context of introductory physics courses. This classification, called the Taxonomy of Introductory Physics Problems (TIPP), relates physics problems to the cognitive processes required to solve them. TIPP was created for designing and clarifying educational objectives, for developing assessments that can evaluate individual component processes of the problem-solving process, and for guiding curriculum design in introductory physics courses, specifically within the context of a "thinking-skills" curriculum. TIPP relies on the following resources: (1) cognitive research findings adopted by physics education research, (2) expert-novice research discoveries acknowledged by physics education research, (3) an educational psychology taxonomy for educational objectives, and (4) various collections of physics problems created by physics education researchers or developed by textbook authors. TIPP was used in the years 2006--2008 to reform the first semester of the introductory algebra-based physics course (called Phys 11) at The George Washington University. The reform sought to transform our curriculum into a "thinking-skills" curriculum that trades "breadth for depth" by focusing on fewer topics while targeting the students' cognitive development. We employed existing research on the physics problem-solving expert-novice behavior, cognitive science and behavioral science findings, and educational psychology recommendations. Our pedagogy relies on didactic constructs such as the GW-ACCESS problem-solving protocol, learning progressions and concept maps that we have developed and implemented in our introductory physics course. These tools were designed based on TIPP. Their purpose is: (1) to help students build local and global coherent knowledge structures, (2) to develop more context-independent problem-solving abilities, (3) to gain confidence in problem solving, and (4) to establish connections between everyday phenomena and underlying physics concepts. We organize traditional and research-based physics problems such that students experience a gradual increase in complexity related to problem context, problem features and cognitive processes needed to solve the problem. The instructional environment that we designed allows for explicit monitoring, control and measurement of the cognitive processes exercised during the instruction period. It is easily adaptable to any kind of curriculum and can be readily adjusted throughout the semester. To assess the development of students' problem-solving abilities, we created rubrics that measure specific aspects of the thinking involved in physics problem solving. The Colorado Learning Attitudes about Science Survey (CLASS) was administered pre- and post-instruction to determine students' shift in dispositions towards learning physics. The Force Concept Inventory (FCI) was administered pre- and post-instruction to determine students' level of conceptual understanding. The results feature improvements in students' problem-solving abilities and in their attitudes towards learning physics.

A Course on the Physics of Urban and Environmental Problems

ERIC Educational Resources Information Center

Marston, Edwin H.

1970-01-01

Presents a physics course for social scientists. Physics problems are presented within the context of several urban and environmental case studies. The problems considered include transportation, air pollution, thermal pollution of water, and scarcity of resources. (LS)

Examining Problem Solving in Physics-Intensive Ph.D. Research

ERIC Educational Resources Information Center

Leak, Anne E.; Rothwell, Susan L.; Olivera, Javier; Zwickl, Benjamin; Vosburg, Jarrett; Martin, Kelly Norris

2017-01-01

Problem-solving strategies learned by physics undergraduates should prepare them for real-world contexts as they transition from students to professionals. Yet, graduate students in physics-intensive research face problems that go beyond problem sets they experienced as undergraduates and are solved by different strategies than are typically…

Top 10 Research Questions Related to Assessing Physical Activity and Its Contexts Using Systematic Observation

ERIC Educational Resources Information Center

McKenzie, Thomas L.; van der Mars, Hans

2015-01-01

Numerous methods are available to assess physical activity (PA) but systematic observation (SO) excels in being able to provide contextually rich data on the setting in which the activity occurs. As SO is particularly useful for determining how activity is influenced by the immediate physical and social environments, its use is becoming more…

Approaches to Interactive Video Anchors in Problem-Based Science Learning

ERIC Educational Resources Information Center

Kumar, David Devraj

2010-01-01

This paper is an invited adaptation of the IEEE Education Society Distinguished Lecture Approaches to Interactive Video Anchors in Problem-Based Science Learning. Interactive video anchors have a cognitive theory base, and they help to enlarge the context of learning with information-rich real-world situations. Carefully selected movie clips and…

Stealing from Physics: Modeling with Mathematical Functions in Data-Rich Contexts

ERIC Educational Resources Information Center

Erickson, Tim

2006-01-01

In the course of a project to create physics education materials for secondary schools in the USA we have, not surprisingly, had insights into how students develop certain mathematical understandings. Some of these translate directly into the mathematics classroom. With our materials, students get data from a variety of sources, data that arise in…

Assessing Student Expertise in Introductory Physics with Isomorphic Problems. II. Effect of Some Potential Factors on Problem Solving and Transfer

ERIC Educational Resources Information Center

Chandralekha; Singh

2008-01-01

In this paper, we explore the use of isomorphic problem pairs (IPPs) to assess introductory physics students' ability to solve and successfully transfer problem-solving knowledge from one context to another in mechanics. We call the paired problems "isomorphic" because they require the same physics principle to solve them. We analyze written…

Reflections on Language and Mathematics Problem Solving: A Case Study of a Bilingual First-Grade Teacher

ERIC Educational Resources Information Center

Musanti, Sandra I.; Celedon-Pattichis, Sylvia; Marshall, Mary E.

2009-01-01

This case study investigates a professional development initiative in which a first-grade bilingual teacher engages in learning and teaching Cognitively Guided Instruction, a framework for understanding student thinking through context-rich word-problem lessons. The study explores (a) the impact of classroom-based professional development on a…

Epistemological beliefs of physics undergraduate and graduate students and faculty in the context of a well-structured and an ill-structured problem

NASA Astrophysics Data System (ADS)

Mercan, Fatih C.

This study examines epistemological beliefs of physics undergraduate and graduate students and faculty in the context of solving a well-structured and an ill-structured problem. The data collection consisted of a think aloud problem solving session followed by a semi-structured interview conducted with 50 participants, 10 participants at freshmen, seniors, masters, PhD, and faculty levels. The data analysis involved (a) identification of the range of beliefs about knowledge in the context of the well-structured and the ill-structured problem solving, (b) construction of a framework that unites the individual beliefs identified in each problem context under the same conceptual base, and (c) comparisons of the problem contexts and expertise level groups using the framework. The results of the comparison of the contexts of the well-structured and the ill-structured problem showed that (a) authoritative beliefs about knowledge were expressed in the well-structured problem context, (b) relativistic and religious beliefs about knowledge were expressed in the ill-structured problem context, and (c) rational, empirical, modeling beliefs about knowledge were expressed in both problem contexts. The results of the comparison of the expertise level groups showed that (a) undergraduates expressed authoritative beliefs about knowledge more than graduate students and faculty did not express authoritative beliefs, (b) faculty expressed modeling beliefs about knowledge more than graduate students and undergraduates did not express modeling beliefs, and (c) there were no differences in rational, empirical, experiential, relativistic, and religious beliefs about knowledge among the expertise level groups. As the expertise level increased the number of participants who expressed authoritative beliefs about knowledge decreased and the number of participants who expressed modeling based beliefs about knowledge increased. The results of this study implied that existing developmental and cognitive models of personal epistemology can explain personal epistemology in physics to a limited extent, however, these models cannot adequately account for the variation of epistemological beliefs across problem contexts. Modeling beliefs about knowledge emerged as a part of personal epistemology and an indicator of epistemological sophistication, which do not develop until extensive experience in the field. Based on these findings, the researcher recommended providing opportunities for practicing model construction for students.

The Context of Ethnicity: Peer Victimization and Adjustment Problems in Early Adolescence

ERIC Educational Resources Information Center

Hoglund, Wendy L. G.; Hosan, Naheed E.

2013-01-01

The current study bridges research on peer relational and physical victimization with research on ethnic victimization and situates this research in the context of ethnic diversity. Specifically, the authors investigate how ethnic, relational, and physical victimization relate to concurrent levels of depression/anxiety and physical aggression and…

Sexuality and Physical Contact in National Social Life, Health, and Aging Project Wave 2

PubMed Central

McClintock, Martha K.; Waite, Linda J.

2014-01-01

Introduction. Wave 2 of the National Social Life, Health, and Aging Project (NSHAP) includes new measures of sexual interest and behavior, as well as new measures of the context of sexual experience and the frequency and appeal of physical contact. This is the first time many of these constructs have been measured in a nationally representative sample. Method. We describe the new measures and compare the distributions of each across gender and age groups, in some cases by partnership status. Results. Two components of sexuality decrease with age among both men and women: frequency of finding an unknown person sexually attractive and receptivity to a partner’s sexual overtures. In contrast, the inclination to make one’s self sexually attractive to others was a more complicated function of partner status, gender, and age: partnered women and unpartnered men made the most effort, with the more effortful gender’s effort decreasing with age. Both men and women find nonsexual physical contact appealing but sexual physical contact is more appealing to men than women. Finally, two fifths of men and women report dissatisfaction with their partner’s frequency of caring behaviors that make later sexual interactions pleasurable, and a fifth of women and a quarter of men who had vaginal sex in the past year report dissatisfaction with amount of foreplay. Discussion. These data offer the opportunity to characterize sexual motivation in older adulthood more precisely and richly and to examine how the context of sexual experience and the nonsexual aspects of physical intimacy correlate with sexual behavior, enjoyment, and problems. PMID:25360027

Social energy exchange theory for postpartum depression.

PubMed

Posmontier, Bobbie; Waite, Roberta

2011-01-01

Postpartum depression (PPD), a significant health problem affecting about 19.4% of postpartum women worldwide, may result in long-term cognitive and behavior problems in children, spousal depression, widespread family dysfunction, and chronic and increasingly severe maternal depression. Although current theoretical frameworks provide a rich context for studying PPD,none provides a framework that specifically addresses the dynamic relationship of the inner personal experience with the social and cultural context of PPD. The authors propose the social energy exchange theory for postpartum depression to understand how PPD impedes this dynamic relationship and suggest it as a theoretical framework for the study of interventions that would target intra- and interpersonal disturbance within the social and cultural context.

Designing authentic assessment: strategies for nurse educators.

PubMed

Poindexter, Kathleen; Hagler, Debra; Lindell, Deborah

2015-01-01

Increased emphasis on health care safety requires renewed attention to teaching and learning processes for future health care professionals. When presented with problems situated in a clinical context, learners have rich opportunities to demonstrate integration of concepts. Authentic assessment is an approach to evaluation of learning through which students can demonstrate acquired knowledge, skills, and attitudes in the context of real-world or realistic nursing practice activities. This article describes features, approaches, and examples of authentic assessment processes in the context of classroom, clinical, and online nursing education.

The role of physicality in rich programming environments

NASA Astrophysics Data System (ADS)

Liu, Allison S.; Schunn, Christian D.; Flot, Jesse; Shoop, Robin

2013-12-01

Computer science proficiency continues to grow in importance, while the number of students entering computer science-related fields declines. Many rich programming environments have been created to motivate student interest and expertise in computer science. In the current study, we investigated whether a recently created environment, Robot Virtual Worlds (RVWs), can be used to teach computer science principles within a robotics context by examining its use in high-school classrooms. We also investigated whether the lack of physicality in these environments impacts student learning by comparing classrooms that used either virtual or physical robots for the RVW curriculum. Results suggest that the RVW environment leads to significant gains in computer science knowledge, that virtual robots lead to faster learning, and that physical robots may have some influence on algorithmic thinking. We discuss the implications of physicality in these programming environments for learning computer science.

Assessing Student Knowledge of Chemistry and Climate Science Concepts Associated with Climate Change: Resources to Inform Teaching and Learning

ERIC Educational Resources Information Center

Versprille, Ashley; Zabih, Adam; Holme, Thomas A.; McKenzie, Lallie; Mahaffy, Peter; Martin, Brian; Towns, Marcy

2017-01-01

Climate change is one of the most critical problems facing citizens today. Chemistry faculty are presented with the problem of making general chemistry content simultaneously relevant and interesting. Using climate science to teach chemistry allows faculty to help students learn chemistry content in a rich context. Concepts related to…

Internet Computer Coaches for Introductory Physics Problem Solving

ERIC Educational Resources Information Center

Xu Ryan, Qing

2013-01-01

The ability to solve problems in a variety of contexts is becoming increasingly important in our rapidly changing technological society. Problem-solving is a complex process that is important for everyday life and crucial for learning physics. Although there is a great deal of effort to improve student problem solving skills throughout the…

A cognitive framework for analyzing and describing introductory students' use and understanding of mathematics in physics

NASA Astrophysics Data System (ADS)

Tuminaro, Jonathan

Many introductory, algebra-based physics students perform poorly on mathematical problem solving tasks in physics. There are at least two possible, distinct reasons for this poor performance: (1) students simply lack the mathematical skills needed to solve problems in physics, or (2) students do not know how to apply the mathematical skills they have to particular problem situations in physics. While many students do lack the requisite mathematical skills, a major finding from this work is that the majority of students possess the requisite mathematical skills, yet fail to use or interpret them in the context of physics. In this thesis I propose a theoretical framework to analyze and describe students' mathematical thinking in physics. In particular, I attempt to answer two questions. What are the cognitive tools involved in formal mathematical thinking in physics? And, why do students make the kinds of mistakes they do when using mathematics in physics? According to the proposed theoretical framework there are three major theoretical constructs: mathematical resources, which are the knowledge elements that are activated in mathematical thinking and problem solving; epistemic games, which are patterns of activities that use particular kinds of knowledge to create new knowledge or solve a problem; and frames, which are structures of expectations that determine how individuals interpret situations or events. The empirical basis for this study comes from videotaped sessions of college students solving homework problems. The students are enrolled in an algebra-based introductory physics course. The videotapes were transcribed and analyzed using the aforementioned theoretical framework. Two important results from this work are: (1) the construction of a theoretical framework that offers researchers a vocabulary (ontological classification of cognitive structures) and grammar (relationship between the cognitive structures) for understanding the nature and origin of mathematical use in the context physics, and (2) a detailed understanding, in terms of the proposed theoretical framework, of the errors that students make when using mathematics in the context of physics.

Applying physics to solve problems in new contexts and representations: Methods Students Use

NASA Astrophysics Data System (ADS)

Zollman, Dean

2010-02-01

``The questions on the test were, like, totally different from the homework.'' All of us have heard variations on this statement. Yet, when we look at the homework and the test questions, we see great similarities. Changing the context or the representation in a physics problem can cause students to have significant difficulties. These difficulties persist sometimes in homework problems, exams and even hands-on activities. With significant effort from Sanjay Rebello our group has been investigating some of the issues which lead to the inability to apply physics learned in one context or with one representation to other situations. By looking at what aspects students are able to use easily and those that they have difficulty applying, we are beginning to understand some of the aspects that help this transfer of learning and some that do not. (Supported by the grants from the National Science Foundation and US Department of Education) )

Using Categorization of Problems as an Instructional Tool to Help Introductory Students Learn Physics

ERIC Educational Resources Information Center

Mason, Andrew; Singh, Chandralekha

2016-01-01

The ability to categorize problems based upon underlying principles, rather than contexts, is considered a hallmark of expertise in physics problem solving. With inspiration from a classic study by Chi, Feltovich, and Glaser, we compared the categorization of 25 introductory mechanics problems based upon similarity of solution by students in large…

Experimenting in a constructivist high school physics laboratory

NASA Astrophysics Data System (ADS)

Roth, Wolff-Michael

Although laboratory activities have long been recognized for their potential to facilitate the learning of science concepts and skills, this potential has yet to be realized. To remediate this problem, researchers have called for constructivist learning environments in which students can pursue open inquiry and frame their own research problems. The present study was designed to describe and understand students' experimenting and problem solving in such an environment. An interpretive research methodology was adopted for the construction of meaning from the data. The data sources included videotapes, their transcripts, student laboratory reports and reflections, interviews with the students, and the teacher's course outline and reflective notes. Forty-six students from three sections of an introductory physics course taught at a private school for boys participated in the study. This article shows the students' remarkable ability and willingness to generate research questions and to design and develop apparatus for data collection. In their effort to frame research questions, students often used narrative explanations to explore and think about the phenomena to be studied. In some cases, blind alleys, students framed research questions and planned experiments that did not lead to the expected results. We observed a remarkable flexibility to deal with problems that arose during the implementation of their plans in the context of the inquiry. These problems, as well as their solutions and the necessary decision-making processes, were characterized by their situated nature. Finally, students pursued meaningful learning during the interpretation of data and graphs to arrive at reasonable answers of their research questions. We concluded that students should be provided with problem-rich learning environments in which they learn to investigate phenomena of their own interest and in which they can develop complex problem-solving skills.

Force, Velocity, and Work: The Effects of Different Contexts on Students' Understanding of Vector Concepts Using Isomorphic Problems

ERIC Educational Resources Information Center

Barniol, Pablo; Zavala, Genaro

2014-01-01

In this article we compare students' understanding of vector concepts in problems with no physical context, and with three mechanics contexts: force, velocity, and work. Based on our "Test of Understanding of Vectors," a multiple-choice test presented elsewhere, we designed two isomorphic shorter versions of 12 items each: a test with no…

Problem-Based Learning in the Physical Science Classroom, K-12

ERIC Educational Resources Information Center

McConnell, Tom J.; Parker, Joyce; Eberhardt, Janet

2018-01-01

"Problem-Based Learning in the Physical Science Classroom, K-12" will help your students truly understand concepts such as motion, energy, and magnetism in true-to-life contexts. The book offers a comprehensive description of why, how, and when to implement problem-based learning (PBL) in your curriculum. Its 14 developmentally…

Sexuality and physical contact in National Social Life, Health, and Aging Project Wave 2.

PubMed

Galinsky, Adena M; McClintock, Martha K; Waite, Linda J

2014-11-01

Wave 2 of the National Social Life, Health, and Aging Project (NSHAP) includes new measures of sexual interest and behavior, as well as new measures of the context of sexual experience and the frequency and appeal of physical contact. This is the first time many of these constructs have been measured in a nationally representative sample. We describe the new measures and compare the distributions of each across gender and age groups, in some cases by partnership status. Two components of sexuality decrease with age among both men and women: frequency of finding an unknown person sexually attractive and receptivity to a partner's sexual overtures. In contrast, the inclination to make one's self sexually attractive to others was a more complicated function of partner status, gender, and age: partnered women and unpartnered men made the most effort, with the more effortful gender's effort decreasing with age. Both men and women find nonsexual physical contact appealing but sexual physical contact is more appealing to men than women. Finally, two fifths of men and women report dissatisfaction with their partner's frequency of caring behaviors that make later sexual interactions pleasurable, and a fifth of women and a quarter of men who had vaginal sex in the past year report dissatisfaction with amount of foreplay. These data offer the opportunity to characterize sexual motivation in older adulthood more precisely and richly and to examine how the context of sexual experience and the nonsexual aspects of physical intimacy correlate with sexual behavior, enjoyment, and problems. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Creating opportunities to influence self-efficacy through modeling instruction

NASA Astrophysics Data System (ADS)

Sawtelle, Vashti; Brewe, Eric; Goertzen, Renee Michelle; Kramer, Laird H.

2012-02-01

In this paper we present an initial analysis connecting key elements of Modeling Instruction (MI) to self-efficacy experience opportunities. Previously, we demonstrated that MI has positive effects on self-efficacy when compared with traditional Lecture instruction [1]. We also found a particularly strong positive effect on the social persuasion source of self-efficacy for women in the MI class. Our current study seeks to understand through what mechanisms MI influences self-efficacy. We demonstrate this connection through an in-depth analysis of video chosen to exemplify Modeling techniques used in a problem-solving episode by three female participants enrolled in a MI introductory physics class. We provide a rich and descriptive analysis of the self-efficacy experiences opportunities within this context and discuss how these opportunities provide a potential explanation of how MI influences self-efficacy.

Interactions Between Mathematics and Physics: The History of the Concept of Function—Teaching with and About Nature of Mathematics

NASA Astrophysics Data System (ADS)

Kjeldsen, Tinne Hoff; Lützen, Jesper

2015-07-01

In this paper, we discuss the history of the concept of function and emphasize in particular how problems in physics have led to essential changes in its definition and application in mathematical practices. Euler defined a function as an analytic expression, whereas Dirichlet defined it as a variable that depends in an arbitrary manner on another variable. The change was required when mathematicians discovered that analytic expressions were not sufficient to represent physical phenomena such as the vibration of a string (Euler) and heat conduction (Fourier and Dirichlet). The introduction of generalized functions or distributions is shown to stem partly from the development of new theories of physics such as electrical engineering and quantum mechanics that led to the use of improper functions such as the delta function that demanded a proper foundation. We argue that the development of student understanding of mathematics and its nature is enhanced by embedding mathematical concepts and theories, within an explicit-reflective framework, into a rich historical context emphasizing its interaction with other disciplines such as physics. Students recognize and become engaged with meta-discursive rules governing mathematics. Mathematics teachers can thereby teach inquiry in mathematics as it occurs in the sciences, as mathematical practice aimed at obtaining new mathematical knowledge. We illustrate such a historical teaching and learning of mathematics within an explicit and reflective framework by two examples of student-directed, problem-oriented project work following the Roskilde Model, in which the connection to physics is explicit and provides a learning space where the nature of mathematics and mathematical practices are linked to natural science.

Toward an Understanding of Development of Learning to Solve Ill-Defined Problems in an Online Context: A Multi-Year Qualitative Exploratory Study

ERIC Educational Resources Information Center

Peddibhotla, Naren

2016-01-01

The case study is a classic tool used in several educational programs that emphasizes solving of illdefined problems. Though it has been used in classroom-based teaching and educators have developed a rich repertoire of methods, its use in online courses presents different challenges. To explore factors that develop skills in solving ill-defined…

Space Strategies for the New Learning Landscape

ERIC Educational Resources Information Center

Dugdale, Shirley

2009-01-01

The Learning Landscape is the total context for students' learning experiences and the diverse landscape of learning settings available today--from specialized to multipurpose, from formal to informal, and from physical to virtual. The goal of the Learning Landscape approach is to acknowledge this richness and maximize encounters among people,…

Do Students Trust in Mathematics or Intuition during Physics Problem Solving? An Epistemic Game Perspective

ERIC Educational Resources Information Center

Yavuz, Ahmet

2015-01-01

This study aims to investigate (1) students' trust in mathematics calculation versus intuition in a physics problem solving and (2) whether this trust is related to achievement in physics in the context of epistemic game theoretical framework. To achieve this research objective, paper-pencil and interview sessions were conducted. A paper-pencil…

The Use of Metacognitive Knowledge Patterns to Compose Physics Higher Order Thinking Problems

ERIC Educational Resources Information Center

Abdullah, Helmi; Malago, Jasruddin D.; Bundu, Patta; Thalib, Syamsul Bachri

2013-01-01

The main aspect in physics learning is the use of equation in problem solving. Equation is a mathematical form of theoretical statements, principles, and laws in physics, and describes a relationship between one concept to another by using a specific symbol. In a context of knowledge dimension, equation is a procedural knowledge. Students are…

Students' Difficulties with Integration in Electricity

ERIC Educational Resources Information Center

Nguyen, Dong-Hai; Rebello, N. Sanjay

2011-01-01

This study investigates the common difficulties that students in introductory physics experience when solving problems involving integration in the context of electricity. We conducted teaching-learning interviews with 15 students in a second-semester calculus-based introductory physics course on several problems involving integration. We found…

Exploring University Students' Expectations and Beliefs about Physics and Physics Learning in a Problem-Based Learning Context

ERIC Educational Resources Information Center

Sahin, Mehmet

2009-01-01

This paper reports the results of an exploratory study aimed to determine university students' expectations and beliefs in a problem-based introductory physics course, how those expectations compare to that of students in other universities, and change as a result of one semester of instruction. In total, 264 freshmen engineering students of Dokuz…

Behaviour of mathematics and physics students in solving problem of Vector-Physics context

NASA Astrophysics Data System (ADS)

Sardi; Rizal, M.; Mansyur, J.

2018-04-01

This research aimed to describe behaviors of mathematics and physics students in solving problem of the vector concept in physics context. The subjects of the research were students who enrolled in Mathematics Education Study Program and Physics Education Study Program of FKIP Universitas Tadulako. The selected participants were students who received the highest score in vector fundamental concept test in each study program. The data were collected through thinking-aloud activity followed by an interview. The steps of data analysis included data reduction, display, and conclusion drawing. The credibility of the data was tested using a triangulation method. Based on the data analysis, it can be concluded that the two groups of students did not show fundamental differences in problem-solving behavior, especially in the steps of understanding the problem (identifying, collecting and analyzing facts and information), planning (looking for alternative strategies) and conducting the alternative strategy. The two groups were differ only in the evaluation aspect. In contrast to Physics students who evaluated their answer, mathematics students did not conducted an evaluation activity on their work. However, the difference was not caused by the differences in background knowledge.

Challenges And Results of the Applications of Fuzzy Logic in the Classification of Rich Galaxy Clusters

NASA Astrophysics Data System (ADS)

Santiago Girola Schneider, Rafael

2015-08-01

The fuzzy logic is a branch of the artificial intelligence founded on the concept that 'everything is a matter of degree.' It intends to create mathematical approximations on the resolution of certain types of problems. In addition, it aims to produce exact results obtained from imprecise data, for which it is particularly useful for electronic and computer applications. This enables it to handle vague or unspecific information when certain parts of a system are unknown or ambiguous and, therefore, they cannot be measured in a reliable manner. Also, when the variation of a variable can produce an alteration on the others.The main focus of this paper is to prove the importance of these techniques formulated from a theoretical analysis on its application on ambiguous situations in the field of the rich clusters of galaxies. The purpose is to show its applicability in the several classification systems proposed for the rich clusters, which are based on criteria such as the level of richness of the cluster, the distribution of the brightest galaxies, whether there are signs of type-cD galaxies or not or the existence of sub-clusters.Fuzzy logic enables the researcher to work with “imprecise” information implementing fuzzy sets and combining rules to define actions. The control systems based on fuzzy logic join input variables that are defined in terms of fuzzy sets through rule groups that produce one or several output values of the system under study. From this context, the application of the fuzzy logic’s techniques approximates the solution of the mathematical models in abstractions about the rich galaxy cluster classification of physical properties in order to solve the obscurities that must be confronted by an investigation group in order to make a decision.

Challenges And Results of the Applications of Fuzzy Logic in the Classification of Rich Galaxy Clusters

NASA Astrophysics Data System (ADS)

Girola Schneider, R.

2017-07-01

The fuzzy logic is a branch of the artificial intelligence founded on the concept that everything is a matter of degree. It intends to create mathematical approximations on the resolution of certain types of problems. In addition, it aims to produce exact results obtained from imprecise data, for which it is particularly useful for electronic and computer applications. This enables it to handle vague or unspecific information when certain parts of a system are unknown or ambiguous and, therefore, they cannot be measured in a reliable manner. Also, when the variation of a variable can produce an alteration on the others The main focus of this paper is to prove the importance of these techniques formulated from a theoretical analysis on its application on ambiguous situations in the field of the rich clusters of galaxies. The purpose is to show its applicability in the several classification systems proposed for the rich clusters, which are based on criteria such as the level of richness of the cluster, the distribution of the brightest galaxies, whether there are signs of type-cD galaxies or not or the existence of sub-clusters. Fuzzy logic enables the researcher to work with "imprecise" information implementing fuzzy sets and combining rules to define actions. The control systems based on fuzzy logic join input variables that are defined in terms of fuzzy sets through rule groups that produce one or several output values of the system under study. From this context, the application of the fuzzy logic's techniques approximates the solution of the mathematical models in abstractions about the rich galaxy cluster classification of physical properties in order to solve the obscurities that must be confronted by an investigation group in order to make a decision.

Assessing Expertise in Introductory Physics Using Categorization Task

ERIC Educational Resources Information Center

Mason, Andrew; Singh, Chandralekha

2011-01-01

The ability to categorize problems based upon underlying principles, rather than surface features or contexts, is considered one of several proxy predictors of expertise in problem solving. With inspiration from the classic study by Chi, Feltovich, and Glaser, we assess the distribution of expertise among introductory physics students by asking…

Geometric Reasoning in an Active-Engagement Upper-Division E&M Classroom

ERIC Educational Resources Information Center

Cerny, Leonard Thomas

2012-01-01

A combination of theoretical perspectives is used to create a rich description of student reasoning when facing a highly-geometric electricity and magnetism problem in an upper-division active-engagement physics classroom at Oregon State University. Geometric reasoning as students encounter problem situations ranging from familiar to novel is…

Physics students' approaches to learning and cognitive processes in solving physics problems

NASA Astrophysics Data System (ADS)

Bouchard, Josee

This study examined traditional instruction and problem-based learning (PBL) approaches to teaching and the extent to which they foster the development of desirable cognitive processes, including metacognition, critical thinking, physical intuition, and problem solving among undergraduate physics students. The study also examined students' approaches to learning and their perceived role as physics students. The research took place in the context of advanced courses of electromagnetism at a Canadian research university. The cognitive science, expertise, physics and science education, instructional psychology, and discourse processes literature provided the framework and background to conceptualize and structure this study. A within-stage mixed-model design was used and a number of instruments, including a survey, observation grids, and problem sets were developed specifically for this study. A special one-week long problem-based learning (PBL) intervention was also designed. Interviews with the instructors participating in the study provided complementary data. Findings include evidence that students in general engage in metacognitive processes in the organization of their personal study time. However, this potential, including the development of other cognitive processes, might not be stimulated as much as it could in the traditional lecture instructional context. The PBL approach was deemed as more empowering for the students. An unexpected finding came from the realisation that a simple exposure to a structured exercise of problem-solving (pre-test) was sufficient to produce superior planning and solving strategies on a second exposure (post-test) even for the students who had not been exposed to any special treatment. Maturation was ruled out as a potential threat to the validity of this finding. Another promising finding appears to be that the problem-based learning (PBL) intervention tends to foster the development of cognitive competencies, particularly physical intuition, even if it was only implemented for a short period of time. Other findings relate to the nature of the cognitive actions and activities that the students engage in when learning to solve electromagnetism problems in a PBL environment for the first time and the tutoring actions that guide students in this context.

Investigating Prospective Teachers' Ability to Write Context-Based Problems

ERIC Educational Resources Information Center

Ültay, Neslihan; Donmez Usta, Necla

2016-01-01

Purpose: The purpose of this study is to investigate the prospective teachers' ability to write context-based problems about the concepts in radioactivity unit. Methodology: The study is carried out in a university in Turkey with 21 prospective teachers in physics, chemistry and biology in 2014-2015 fall terms. In the study, data are collected…

The first stars: our evolving theoretical picture

NASA Astrophysics Data System (ADS)

Bromm, V.

This brief review will discuss what we have learned about the formation, properties, evolution and death of the first stars, the so-called Population III (Pop III). It is crucial to embed the problem into its proper cosmological context, including insights into the particle-physics nature of dark matter. This is a good time to reflect on where we are, just ahead of the James Webb Space Telescope (JWST) launch, and of the imminent arrival of a suite of next-generation observational facilities. How can we test our emerging theoretical picture with observations both in-situ, at high redshifts, and in our local cosmic neighborhood? This may indeed be our main challenge for the near future, given that individual Pop III stars cannot be directly observed, unless we get very lucky, and catch them at the moment of their death as transient events. We therefore need powerful diagnostics that make use of an increasingly rich data set of indirect clues.

A reflective lens: applying critical systems thinking and visual methods to ecohealth research.

PubMed

Cleland, Deborah; Wyborn, Carina

2010-12-01

Critical systems methodology has been advocated as an effective and ethical way to engage with the uncertainty and conflicting values common to ecohealth problems. We use two contrasting case studies, coral reef management in the Philippines and national park management in Australia, to illustrate the value of critical systems approaches in exploring how people respond to environmental threats to their physical and spiritual well-being. In both cases, we used visual methods--participatory modeling and rich picturing, respectively. The critical systems methodology, with its emphasis on reflection, guided an appraisal of the research process. A discussion of these two case studies suggests that visual methods can be usefully applied within a critical systems framework to offer new insights into ecohealth issues across a diverse range of socio-political contexts. With this article, we hope to open up a conversation with other practitioners to expand the use of visual methods in integrated research.

Teacher and Student Reflections on ICT-Rich Science Inquiry

ERIC Educational Resources Information Center

Williams, P. John; Otrel-Cass, Kathrin

2017-01-01

Background: Inquiry learning in science provides authentic and relevant contexts in which students can create knowledge to solve problems, make decisions and find solutions to issues in today's world. The use of electronic networks can facilitate this interaction, dialogue and sharing, and adds a new dimension to classroom pedagogy. Purpose: This…

Promoting Positive Academic Dispositions Using a Web-Based PBL Environment: The GlobalEd 2 Project

ERIC Educational Resources Information Center

Brown, Scott W.; Lawless, Kimberly A.; Boyer, Mark A.

2013-01-01

Problem-based learning (PBL) is an instructional design approach for promoting student learning, understanding and knowledge development in context rich settings. Previous PBL research has primarily focused on face-to-face learning environments, but current technologies afford PBL designers the opportunities to create online, virtual, PBL…

Gaming Personality and Game Dynamics in Online Discussion Instructions

ERIC Educational Resources Information Center

Tu, Chih-Hsiung; Yen, Cherng-Jyh; Sujo-Montes, Laura; Roberts, Gayle A.

2015-01-01

Gamification is the use of game mechanics to drive game-like engagements and actions. It applies game mechanics, dynamics and frameworks to promote desired learning behaviours. Positive and effective gamification could enhance learning and engage learners in more social and context-rich decision-making for problem-solving in learning tasks.…

Increasing Students' Science Writing Skills through a PBL Simulation

ERIC Educational Resources Information Center

Brown, Scott W.; Lawless, Kimberly A.; Rhoads, Christopher; Newton, Sarah D.; Lynn, Lisa

2016-01-01

Problem-based learning (PBL) is an instructional design approach for promoting student learning, in context-rich settings. GlobalEd 2 (GE2) is PBL intervention that combines face-to-face and online environments into a 12-week simulation of international negotiations of science advisors on global water resource issues. The GE2 environment is…

Forming Physical Education Teachers' Pedagogical Mastery in the Context of Native and Foreign Scholars' Views

ERIC Educational Resources Information Center

Maksymchuk, Iryna

2016-01-01

The article deals with studying the process of forming physical education teachers' pedagogical mastery in the context of native and foreign scholars' views. It has been indicated that the problem of pedagogical activity and pedagogical mastery efficiency has been raised in the works of a number of scholars who developed the principles and…

The Turn of the Screw: An Exercise in Protein Secondary Structure

ERIC Educational Resources Information Center

Pikaart, Michael

2011-01-01

An exercise using simple paper strips to illustrate protein helical and sheet secondary structures is presented. Drawing on the rich historical context of the use of physical models in protein biochemistry by early practitioners, in particular Linus Pauling, the purpose of this activity is to cultivate in students a hands-on, intuitive sense of…

[Neural basis of self-face recognition: social aspects].

PubMed

Sugiura, Motoaki

2012-07-01

Considering the importance of the face in social survival and evidence from evolutionary psychology of visual self-recognition, it is reasonable that we expect neural mechanisms for higher social-cognitive processes to underlie self-face recognition. A decade of neuroimaging studies so far has, however, not provided an encouraging finding in this respect. Self-face specific activation has typically been reported in the areas for sensory-motor integration in the right lateral cortices. This observation appears to reflect the physical nature of the self-face which representation is developed via the detection of contingency between one's own action and sensory feedback. We have recently revealed that the medial prefrontal cortex, implicated in socially nuanced self-referential process, is activated during self-face recognition under a rich social context where multiple other faces are available for reference. The posterior cingulate cortex has also exhibited this activation modulation, and in the separate experiment showed a response to attractively manipulated self-face suggesting its relevance to positive self-value. Furthermore, the regions in the right lateral cortices typically showing self-face-specific activation have responded also to the face of one's close friend under the rich social context. This observation is potentially explained by the fact that the contingency detection for physical self-recognition also plays a role in physical social interaction, which characterizes the representation of personally familiar people. These findings demonstrate that neuroscientific exploration reveals multiple facets of the relationship between self-face recognition and social-cognitive process, and that technically the manipulation of social context is key to its success.

Rethinking the Effects of Classroom Activity Structure on the Engagement of Low-Achieving Students

ERIC Educational Resources Information Center

Kelly, Sean; Turner, Julianne

2009-01-01

Background/Context: A common perspective found in the literature on classroom activity structures hypothesizes that a whole-class mode of instruction is linked with increased problems of achievement motivation for low-achieving students. If whole-class methods of instruction (e.g., recitation-style question-and-answer sessions) are rich in…

How Students Use Physics to Reason about Calculus Tasks

ERIC Educational Resources Information Center

Marrongelle, Karen A.

2004-01-01

The present research study investigates how undergraduate students in an integrated calculus and physics class use physics to help them solve calculus problems. Using Zandieh's (2000) framework for analyzing student understanding of derivative as a starting point, this study adds detail to her "paradigmatic physical" context and begins to address…

Contrasting grading approaches in introductory physics and quantum mechanics: The case of graduate teaching assistants

NASA Astrophysics Data System (ADS)

Marshman, Emily; Sayer, Ryan; Henderson, Charles; Singh, Chandralekha

2017-06-01

At large research universities, physics graduate teaching assistants (TAs) are often responsible for grading in courses at all levels. However, few studies have focused on TAs' grading practices in introductory and advanced physics courses. This study was designed to investigate whether physics graduate TAs grade students in introductory physics and quantum mechanics using different criteria and if so, why they may be inclined to do so. To investigate possible discrepancies in TAs' grading approaches in courses at different levels, we implemented a sequence of instructional activities in a TA professional development course that asked TAs to grade student solutions of introductory physics and upper-level quantum mechanics problems and explain why, if at all, their grading approaches were different or similar in the two contexts. We analyzed the differences in TAs' grading approaches in the two contexts and discuss the reasons they provided for the differences in their grading approaches in introductory physics and quantum mechanics in individual interviews, class discussions, and written responses. We find that a majority of the TAs graded solutions to quantum mechanics problems differently than solutions to introductory physics problems. In quantum mechanics, the TAs focused more on physics concepts and reasoning and penalized students for not showing evidence of understanding. The findings of the study have implications for TA professional development programs, e.g., the importance of helping TAs think about the difficulty of a problem from an introductory students' perspective and reflecting on the benefits of formative assessment.

Incorporating Problem-Based Learning in Physical Education Teacher Education

ERIC Educational Resources Information Center

Hushman, Glenn; Napper-Owen, Gloria

2011-01-01

Problem-based learning (PBL) is an educational method that identifies a problem as a context for student learning. Critical-thinking skills, deductive reasoning, knowledge, and behaviors are developed as students learn how theory can be applied to practical settings. Problem-based learning encourages self-direction, lifelong learning, and sharing…

Talking Physics: Two Case Studies on Short Answers and Self-explanation in Learning Physics

NASA Astrophysics Data System (ADS)

Badeau, Ryan C.

This thesis explores two case studies into the use of short answers and self-explanation to improve student learning in physics. The first set of experiments focuses on the role of short answer questions in the context of computer-based instruction. Through a series of six experiments, we compare and evaluate the performance of computer-assessed short answer questions versus multiple choice for training conceptual topics in physics, controlling for feedback between the two formats. In addition to finding overall similar improvements on subsequent student performance and retention, we identify unique differences in how students interact with the treatments in terms of time spent on feedback and performance on follow-up short answer assessment. In addition, we identify interactions between the level of interactivity of the training, question format, and student attitudinal ratings of each respective training. The second case study focuses on the use of worked examples in the context of multi-concept physics problems - which we call "synthesis problems." For this part of the thesis, four experiments were designed to evaluate the effectiveness of two instructional methods employing worked examples on student performance with synthesis problems; these instructional techniques, analogical comparison and self-explanation, have previously been studied primarily in the context of single-concept problems. As such, the work presented here represents a novel focus on extending these two techniques to this class of more complicated physics problem. Across the four experiments, both self-explanation and certain kinds of analogical comparison of worked examples significantly improved student performance on a target synthesis problem, with distinct improvements in recognition of the relevant concepts. More specifically, analogical comparison significantly improved student performance when the comparisons were invoked between worked synthesis examples. In contrast, similar comparisons between corresponding pairs of worked single-concept examples did not significantly improve performance. On a more complicated synthesis problem, self-explanation was significantly more effective than analogical comparison, potentially due to differences in how successfully students encoded the full structure of the worked examples. Finally, we find that the two techniques can be combined for additional benefit, with the trade-off of slightly more time-on-task.

Beyond "Inert" Ideas to Teaching General Chemistry from Rich Contexts: Visualizing the Chemistry of Climate Change (VC3)

ERIC Educational Resources Information Center

Mahaffy, Peter G.; Holme, Thomas A.; Martin-Visscher, Leah; Martin, Brian E.; Versprille, Ashley; Kirchhoff, Mary; McKenzie, Lallie; Town, Marcy

2017-01-01

As one approach to moving beyond transmitting "inert" ideas to chemistry students, we use the term "teaching from rich contexts" to describe implementations of case studies or context-based learning based on systems thinking that provide deep and rich opportunities for learning crosscutting concepts through contexts. This…

The Role of Content Knowledge in Ill-Structured Problem Solving for High School Physics Students

NASA Astrophysics Data System (ADS)

Milbourne, Jeff; Wiebe, Eric

2018-02-01

While Physics Education Research has a rich tradition of problem-solving scholarship, most of the work has focused on more traditional, well-defined problems. Less work has been done with ill-structured problems, problems that are better aligned with the engineering and design-based scenarios promoted by the Next Generation Science Standards. This study explored the relationship between physics content knowledge and ill-structured problem solving for two groups of high school students with different levels of content knowledge. Both groups of students completed an ill-structured problem set, using a talk-aloud procedure to narrate their thought process as they worked. Analysis of the data focused on identifying students' solution pathways, as well as the obstacles that prevented them from reaching "reasonable" solutions. Students with more content knowledge were more successful reaching reasonable solutions for each of the problems, experiencing fewer obstacles. These students also employed a greater variety of solution pathways than those with less content knowledge. Results suggest that a student's solution pathway choice may depend on how she perceives the problem.

Students' Misconceptions about Heat Transfer Mechanisms and Elementary Kinetic Theory

ERIC Educational Resources Information Center

Pathare, S. R.; Pradhan, H. C.

2010-01-01

Heat and thermodynamics is a conceptually rich area of undergraduate physics. In the Indian context in particular there has been little work done in this area from the point of view of misconceptions. This prompted us to undertake a study in this area. We present a study of students' misconceptions about heat transfer mechanisms, i.e. conduction,…

Studying PubMed usages in the field for complex problem solving: Implications for tool design

PubMed Central

Song, Jean; Tonks, Jennifer Steiner; Meng, Fan; Xuan, Weijian; Ameziane, Rafiqa

2012-01-01

Many recent studies on MEDLINE-based information seeking have shed light on scientists’ behaviors and associated tool innovations that may improve efficiency and effectiveness. Few if any studies, however, examine scientists’ problem-solving uses of PubMed in actual contexts of work and corresponding needs for better tool support. Addressing this gap, we conducted a field study of novice scientists (14 upper level undergraduate majors in molecular biology) as they engaged in a problem solving activity with PubMed in a laboratory setting. Findings reveal many common stages and patterns of information seeking across users as well as variations, especially variations in cognitive search styles. Based on findings, we suggest tool improvements that both confirm and qualify many results found in other recent studies. Our findings highlight the need to use results from context-rich studies to inform decisions in tool design about when to offer improved features to users. PMID:24376375

Grasping the invisible: semantic processing of abstract words.

PubMed

Zdrazilova, Lenka; Pexman, Penny M

2013-12-01

The problem of how abstract word meanings are represented has been a challenging one. In the present study, we extended the semantic richness approach (e.g., Yap, Tan, Pexman, & Hargreaves in Psychonomic Bulletin & Review 18:742-750, 2011) to abstract words, examining the effects of six semantic richness variables on lexical-semantic processing for 207 abstract nouns. The candidate richness dimensions were context availability (CA), sensory experience rating (SER), valence, arousal, semantic neighborhood (SN), and number of associates (NoA). The behavioral tasks were lexical decision (LDT) and semantic categorization (SCT). Our results showed that the semantic richness variables were significantly related to both LDT and SCT latencies, even after lexical and orthographic factors were controlled. The patterns of richness effects varied across tasks, with CA effects in the LDT, and SER and valence effects in the SCT. These results provide new insight into how abstract meanings may be grounded, and are consistent with a dynamic, multidimensional framework for semantic processing.

Engineering Problem-Solving Knowledge: The Impact of Context

ERIC Educational Resources Information Center

Wolff, Karin

2017-01-01

Employer complaints of engineering graduate inability to "apply knowledge" suggests a need to interrogate the complex theory-practice relationship in twenty-first century real world contexts. Focussing specifically on the application of mathematics, physics and logic-based disciplinary knowledge, the research examines engineering…

Sixth-Grade Physical Education: An Acculturation of Bullying and Fear

ERIC Educational Resources Information Center

O'Connor, Jamie A.; Graber, Kim C.

2014-01-01

Purpose: Although bullying is recognized as a serious problem among adolescents, more information is needed regarding bullying within the context of physical education. Grounded in a social-ecological framework, the purpose of this investigation was to discover the perceptions students and teachers have about bullying in physical education and…

Revisiting the Velocity Selector Problem with VPython

ERIC Educational Resources Information Center

Milbourne, Jeff; Lim, Halson

2015-01-01

The velocity selector is a classic first-year physics problem that demonstrates the influence of perpendicular electric and magnetic fields on a charged particle. Traditionally textbooks introduce this problem in the context of balanced forces, often asking for field strengths that would allow a charged particle, with a specific target velocity,…

Motivating Calculus-Based Kinematics Instruction with Super Mario Bros

NASA Astrophysics Data System (ADS)

Nordine, Jeffrey C.

2011-09-01

High-quality physics instruction is contextualized, motivates students to learn, and represents the discipline as a way of investigating the world rather than as a collection of facts and equations. Inquiry-oriented pedagogy, such as problem-based instruction, holds great promise for both teaching physics content and representing the process of doing real science.2 A challenge for physics teachers is to find instructional contexts that are meaningful, accessible, and motivating for students. Today's students are spending a growing fraction of their lives interacting with virtual environments, and these environments—physically realistic or not—can provide valuable contexts for physics explorations3-5 and lead to thoughtful discussions about decisions that programmers make when designing virtual environments. In this article, I describe a problem-based approach to calculus-based kinematics instruction that contextualizes students' learning within the Super Mario Bros. video game—a game that is more than 20 years old, but still remarkably popular with today's high school and college students.

Focus group discussion in mathematical physics learning

NASA Astrophysics Data System (ADS)

Ellianawati; Rudiana, D.; Sabandar, J.; Subali, B.

2018-03-01

The Focus Group Discussion (FGD) activity in Mathematical Physics learning has helped students perform the stages of problem solving reflectively. The FGD implementation was conducted to explore the problems and find the right strategy to improve the students' ability to solve the problem accurately which is one of reflective thinking component that has been difficult to improve. The research method used is descriptive qualitative by using single subject response in Physics student. During the FGD process, one student was observed of her reflective thinking development in solving the physics problem. The strategy chosen in the discussion activity was the Cognitive Apprenticeship-Instruction (CA-I) syntax. Based on the results of this study, it is obtained the information that after going through a series of stages of discussion, the students' reflective thinking skills is increased significantly. The scaffolding stage in the CA-I model plays an important role in the process of solving physics problems accurately. Students are able to recognize and formulate problems by describing problem sketches, identifying the variables involved, applying mathematical equations that accord to physics concepts, executing accurately, and applying evaluation by explaining the solution to various contexts.

Evolution of School Physics in the People's Republic of China.

ERIC Educational Resources Information Center

Wang, Jianjun

This paper traces the evolution of school physics in China and elaborates on the current situation, ongoing experiments, and problems of school physics in terms of the historical, cultural, political, and social contexts in China. School physics as a major subject was imported into China almost wholesale by the end of the 19th century.…

Consideration of learning orientations as an application of achievement goals in evaluating life science majors in introductory physics

NASA Astrophysics Data System (ADS)

Mason, Andrew J.; Bertram, Charles A.

2018-06-01

When considering performing an Introductory Physics for Life Sciences course transformation for one's own institution, life science majors' achievement goals are a necessary consideration to ensure the pedagogical transformation will be effective. However, achievement goals are rarely an explicit consideration in physics education research topics such as metacognition. We investigate a sample population of 218 students in a first-semester introductory algebra-based physics course, drawn from 14 laboratory sections within six semesters of course sections, to determine the influence of achievement goals on life science majors' attitudes towards physics. Learning orientations that, respectively, pertain to mastery goals and performance goals, in addition to a learning orientation that does not report a performance goal, were recorded from students in the specific context of learning a problem-solving framework during an in-class exercise. Students' learning orientations, defined within the context of students' self-reported statements in the specific context of a problem-solving-related research-based course implementation, are compared to pre-post results on physics problem-solving items in a well-established attitudinal survey instrument, in order to establish the categories' validity. In addition, mastery-related and performance-related orientations appear to extend to overall pre-post attitudinal shifts, but not to force and motion concepts or to overall course grade, within the scope of an introductory physics course. There also appears to be differentiation regarding overall course performance within health science majors, but not within biology majors, in terms of learning orientations; however, health science majors generally appear to fare less well on all measurements in the study than do biology majors, regardless of learning orientations.

Student Understanding of Cross Product Direction and Use of Right-hand Rules: An Exploration of Representation and Context-dependence

NASA Astrophysics Data System (ADS)

Kustusch, Mary Bridget

2011-12-01

Students in introductory physics struggle with vector algebra and with cross product direction in particular. Some have suggested that this may be due to misapplied right-hand rules, but there are few studies that have had the resolution to explore this. Additionally, previous research on student understanding has noted several kinds of representation-dependence of student performance with vector algebra in both physics and non-physics (or math) contexts (e.g. Hawkins et al., 2009; Van Deventer, 2008). Yet with few exceptions (e.g. Scaife and Heckler, 2010), these findings have not been applied to cross product direction questions or the use of right-hand rules. Also, the extensive work in spatial cognition is particularly applicable to cross product direction due to the spatial and kinesthetic nature of the right-hand rule. A synthesis of the literature from these various fields reveals four categories of problem features likely to impact the understanding of cross product direction: (1) the type of reasoning required, (2) the orientation of the vectors, (3) the need for parallel transport, and (4) the physics context and features (or lack thereof). These features formed the basis of the present effort to systematically explore the context-dependence and representation- dependence of student performance on cross product direction questions. This study used a mix of qualitative and quantitative techniques to analyze twenty-seven individual think-aloud interviews. During these interviews, second semester introductory physics students answered 80-100 cross product direction questions in different contexts and with varying problem features. These features were then used as the predictors in regression analyses for correctness and response time. In addition, each problem was coded for the methods used and the errors made to gain a deeper understanding of student behavior and the impact of these features. The results revealed a wide variety of methods (including six different right-hand rules), many different types of errors, and significant context-dependence and representation-dependence for the features mentioned above. Problems that required reasoning backward to find A⃗ (for C⃗=A⃗ xB⃗ ) presented the biggest challenge for students. Participants who recognized the non-commutativity of the cross product would often reverse the order ( B⃗xA⃗ ) on these problems. Also, this error occurred less frequently when a Guess and Check method was used in addition to the right-hand rule. Three different aspects of orientation had a significant impact on performance: (1) the physical discomfort of using a right-hand rule, (2) the plane of the given vectors, and to a lesser extent, (3) the angle between the vectors. One participant was more likely to switch the order of the vectors for the physically awkward orientations than for the physically easy orientations; and there was evidence that some of the difficulty with vector orientations that were not in the xy-plane was due to misinterpretations of the into and out of the page symbols. The impact of both physical discomfort and the plane of the vectors was reduced when participants rotated the paper. Unlike other problem features, the issue of parallel transport did not appear to be nearly as prevalent for cross product direction as it is for vector addition and subtraction. In addition to these findings, this study confirmed earlier findings regarding physics difficulties with magnetic field and magnetic force, such as differences in performance based on the representation of magnetic field (Scaife and Heckler, 2010) and confusion between electric and magnetic fields (Maloney et al., 2001). It also provided evidence of physics difficulties with magnetic field and magnetic force that have been suspected but never explored, specifically the impact of the sign of the charge and the observation location. This study demonstrated that student difficulty with cross product direction is not as simple as misapplied right-hand rules, although this is an issue. Student behavior on cross product direction questions is significantly dependent on both the context of the question and the representation of various problem features. Although more research is necessary, particularly in regard to individual differences, this study represents a significant step forward in our understanding of student difficulties with cross product direction.

Attitudes about high school physics in relationship to gender and ethnicity: A mixed method analysis

NASA Astrophysics Data System (ADS)

Hafza, Rabieh Jamal

There is an achievement gap and lack of participation in science, technology, engineering, and math (STEM) by minority females. The number of minority females majoring in STEM related fields and earning advanced degrees in these fields has not significantly increased over the past 40 years. Previous research has evaluated the relationship between self-identity concept and factors that promote the academic achievement as well the motivation of students to study different subject areas. This study examined the interaction between gender and ethnicity in terms of physics attitudes in the context of real world connections, personal interest, sense making/effort, problem solving confidence, and problem solving sophistication. The Colorado Learning Attitudes about Science Survey (CLASS) was given to 131 students enrolled in physics classes. There was a statistically significant Gender*Ethnicity interaction for attitude in the context of Real World Connections, Personal Interest, Sense Making/Effort, Problem Solving Confidence, and Problem Solving Sophistication as a whole. There was also a statistically significant Gender*Ethnicity interaction for attitude in the context of Real World Connections, Personal Interest, and Sense Making/Effort individually. Five Black females were interviewed to triangulate the quantitative results and to describe the experiences of minority females taking physics classes. There were four themes that emerged from the interviews and supported the findings from the quantitative results. The data supported previous research done on attitudes about STEM. The results reported that Real World Connections and Personal Interest could be possible factors that explain the lack of participation and achievement gaps that exists among minority females.

Role of multiple representations in physics problem solving

NASA Astrophysics Data System (ADS)

Maries, Alexandru

This thesis explores the role of multiple representations in introductory physics students' problem solving performance through several investigations. Representations can help students focus on the conceptual aspects of physics and play a major role in effective problem solving. Diagrammatic representations can play a particularly important role in the initial stages of conceptual analysis and planning of the problem solution. Findings suggest that students who draw productive diagrams are more successful problem solvers even if their approach is primarily mathematical. Furthermore, students provided with a diagram of the physical situation presented in a problem sometimes exhibited deteriorated performance. Think-aloud interviews suggest that this deteriorated performance is in part due to reduced conceptual planning time which caused students to jump to the implementation stage without fully understanding the problem and planning problem solution. Another study investigated two interventions aimed at improving introductory students' representational consistency between mathematical and graphical representations and revealed that excessive scaffolding can have a detrimental effect. The detrimental effect was partly due to increased cognitive load brought on by the additional steps and instructions. Moreover, students who exhibited representational consistency also showed improved problem solving performance. The final investigation is centered on a problem solving task designed to provide information about the pedagogical content knowledge (PCK) of graduate student teaching assistants (TAs). In particular, the TAs identified what they considered to be the most common difficulties of introductory physics students related to graphical representations of kinematics concepts as they occur in the Test of Understanding Graphs in Kinematics (TUG-K). As an extension, the Force Concept Inventory (FCI) was also used to assess this aspect of PCK related to knowledge of student difficulties of both physics instructors and TAs. We find that teaching an independent course and recent teaching experience do not correlate with improved PCK. In addition, the performance of American TAs, Chinese TAs and other foreign TAs in identifying common student difficulties both in the context of the TUG-K and in the context of the FCI is similar. Moreover, there were many common difficulties of introductory physics students that were not identified by many instructors and TAs.

Student reasoning about graphs in different contexts

NASA Astrophysics Data System (ADS)

Ivanjek, Lana; Susac, Ana; Planinic, Maja; Andrasevic, Aneta; Milin-Sipus, Zeljka

2016-06-01

This study investigates university students' graph interpretation strategies and difficulties in mathematics, physics (kinematics), and contexts other than physics. Eight sets of parallel (isomorphic) mathematics, physics, and other context questions about graphs, which were developed by us, were administered to 385 first-year students at the Faculty of Science, University of Zagreb. Students were asked to provide explanations and/or mathematical procedures with their answers. Students' main strategies and difficulties identified through the analysis of those explanations and procedures are described. Student strategies of graph interpretation were found to be largely context dependent and domain specific. A small fraction of students have used the same strategy in all three domains (mathematics, physics, and other contexts) on most sets of parallel questions. Some students have shown indications of transfer of knowledge in the sense that they used techniques and strategies developed in physics for solving (or attempting to solve) other context problems. In physics, the preferred strategy was the use of formulas, which sometimes seemed to block the use of other, more productive strategies which students displayed in other domains. Students' answers indicated the presence of slope-height confusion and interval-point confusion in all three domains. Students generally better interpreted graph slope than the area under a graph, although the concept of slope still seemed to be quite vague for many. The interpretation of the concept of area under a graph needs more attention in both physics and mathematics teaching.

Fuel/oxidizer-rich high-pressure preburners. [staged-combustion rocket engine

NASA Technical Reports Server (NTRS)

Schoenman, L.

1981-01-01

The analyses, designs, fabrication, and cold-flow acceptance testing of LOX/RP-1 preburner components required for a high-pressure staged-combustion rocket engine are discussed. Separate designs of injectors, combustion chambers, turbine simulators, and hot-gas mixing devices are provided for fuel-rich and oxidizer-rich operation. The fuel-rich design addresses the problem of non-equilibrium LOX/RP-1 combustion. The development and use of a pseudo-kinetic combustion model for predicting operating efficiency, physical properties of the combustion products, and the potential for generating solid carbon is presented. The oxygen-rich design addresses the design criteria for the prevention of metal ignition. This is accomplished by the selection of materials and the generation of well-mixed gases. The combining of unique propellant injector element designs with secondary mixing devices is predicted to be the best approach.

The Crisis in High-School Physics Education: Overview of the Problem.

ERIC Educational Resources Information Center

Layman, John W.

1983-01-01

Discusses the current crisis in science education, focusing on declining physics enrollments and physics teacher shortages. Indicates that the present situation is the culmination of a long trend, interrupted only weakly in the sputnik era, and that the state of the economy may provide a new context for examining the issues. (JN)

Citrus Quality Control: An NMR/MRI Problem-Based Experiment

ERIC Educational Resources Information Center

Erhart, Sarah E.; McCarrick, Robert M.; Lorigan, Gary A.; Yezierski, Ellen J.

2016-01-01

An experiment seated in an industrial context can provide an engaging framework and unique learning opportunity for an upper-division physical chemistry laboratory. An experiment that teaches NMR/MRI through a problem-based quality control of citrus products was developed. In this experiment, using a problem-based learning (PBL) approach, students…

Exploring the Physics of Music with Temperament Studio

NASA Astrophysics Data System (ADS)

Durfee, Dallin; Colton, John

2016-03-01

The physics of waves, resonance, harmonics, and beats has determined how musical instruments are tuned, and has even affected the kinds of music written in different time periods. The laws of physics make it impossible for any fixed scale to have perfect consonance for all chords in all keys, and as a result, various musical scales, or temperaments, have been developed and used throughout history. The study of musical temperament is a rich application of wave physics. It ties several principles together in a context which can be very motivating for students. Furthermore, the topic is accessible to students in introductory classes. We have developed an open source application called Temperament Studio which allows students to explore musical temperament and to hear and measure the effects predicted by wave physics.

Examining the cost effectiveness of interventions to promote the physical health of people with mental health problems: a systematic review

PubMed Central

2013-01-01

Background Recently attention has begun to focus not only on assessing the effectiveness of interventions to tackle mental health problems, but also on measures to prevent physical co-morbidity. Individuals with mental health problems are at significantly increased risk of chronic physical health problems, such as cardiovascular disease or diabetes, as well as reduced life expectancy. The excess costs of co-morbid physical and mental health problems are substantial. Potentially, measures to reduce the risk of co-morbid physical health problems may represent excellent value for money. Methods To conduct a systematic review to determine what is known about economic evaluations of actions to promote better physical health in individuals identified as having a clinically diagnosed mental disorder, but no physical co-morbidity. Systematic searches of databases were supplemented by hand searches of relevant journals and websites. Results Of 1970 studies originally assessed, 11 met our inclusion criteria. In addition, five protocols for other studies were also identified. Studies looked at exercise programmes, nutritional advice, smoking, alcohol and drug cessation, and reducing the risk of blood borne infectious diseases such as HIV/AIDS and hepatitis. All of the lifestyle and smoking cessation studies focused on people with depression and anxiety disorders. Substance abuse and infectious disease prevention studies focused on people with psychoses and bipolar disorder. Conclusions There is a very small, albeit growing, literature on the cost effectiveness of interventions to promote the physical health of people with mental health problems. Most studies suggest that value for money actions in specific contexts and settings are available. Given that the success or failure of health promoting interventions can be very context specific, more studies are needed in more settings, focused on different population groups with different mental health problems and reporting intermediate and long term outcomes. There is a need to better distinguish between resource use and costs in a transparent manner, including impacts outside of the health care system. Issues such as programme fidelity, uptake and adherence should also be accounted for in economic analysis. The role of behavioural psychological techniques to influence health behaviours might also be considered. PMID:23988266

Examining the cost effectiveness of interventions to promote the physical health of people with mental health problems: a systematic review.

PubMed

Park, A-La; McDaid, David; Weiser, Prisca; Von Gottberg, Carolin; Becker, Thomas; Kilian, Reinhold

2013-08-29

Recently attention has begun to focus not only on assessing the effectiveness of interventions to tackle mental health problems, but also on measures to prevent physical co-morbidity. Individuals with mental health problems are at significantly increased risk of chronic physical health problems, such as cardiovascular disease or diabetes, as well as reduced life expectancy. The excess costs of co-morbid physical and mental health problems are substantial. Potentially, measures to reduce the risk of co-morbid physical health problems may represent excellent value for money. To conduct a systematic review to determine what is known about economic evaluations of actions to promote better physical health in individuals identified as having a clinically diagnosed mental disorder, but no physical co-morbidity. Systematic searches of databases were supplemented by hand searches of relevant journals and websites. Of 1970 studies originally assessed, 11 met our inclusion criteria. In addition, five protocols for other studies were also identified. Studies looked at exercise programmes, nutritional advice, smoking, alcohol and drug cessation, and reducing the risk of blood borne infectious diseases such as HIV/AIDS and hepatitis. All of the lifestyle and smoking cessation studies focused on people with depression and anxiety disorders. Substance abuse and infectious disease prevention studies focused on people with psychoses and bipolar disorder. There is a very small, albeit growing, literature on the cost effectiveness of interventions to promote the physical health of people with mental health problems. Most studies suggest that value for money actions in specific contexts and settings are available. Given that the success or failure of health promoting interventions can be very context specific, more studies are needed in more settings, focused on different population groups with different mental health problems and reporting intermediate and long term outcomes. There is a need to better distinguish between resource use and costs in a transparent manner, including impacts outside of the health care system. Issues such as programme fidelity, uptake and adherence should also be accounted for in economic analysis. The role of behavioural psychological techniques to influence health behaviours might also be considered.

Explicit reflection in an introductory physics course

NASA Astrophysics Data System (ADS)

Scott, Michael Lee

This dissertation details a classroom intervention that supplements assigned in-class problems in weekly problem sets with reflective activities that are aimed to assist in knowledge integration. Using the framework of cognitive load theory, this intervention should assist in schema acquisition leading to (1) students recognizing the use and appropriately applying physical concepts across different problem contexts, and (2) enhanced physics understanding of students resulting in improved class performance. The intervention was embedded in the discussion component of an introductory, university physics course, and spanned a 14-week period. Evaluation of the intervention was based on the relative performance between a control and treatment group. Instruments used in this study to assess performance included the Force Concept Inventory (FCI), a physics problem categorization test, and four class exams. A full discussion of this implementation and the accompanying measures will be given. Possible limitations to this study and lines of future research will be proposed.

The Ecocultural Context and Child Behavior Problems: A Qualitative Analysis in Rural Nepal

PubMed Central

Burkey, Matthew D.; Ghimire, Lajina; Adhikari, Ramesh Prasad; Wissow, Lawrence S.; Jordans, Mark J.D.; Kohrt, Brandon A.

2016-01-01

Commonly used paradigms for studying child psychopathology emphasize individual-level factors and often neglect the role of context in shaping risk and protective factors among children, families, and communities. To address this gap, we evaluated influences of ecocultural contextual factors on definitions, development of, and responses to child behavior problems and examined how contextual knowledge can inform culturally responsive interventions. We drew on Super and Harkness’ “developmental niche” framework to evaluate the influences of physical and social settings, childcare customs and practices, and parental ethnotheories on the definitions, development of, and responses to child behavior problems in a community in rural Nepal. Data were collected between February and October 2014 through in-depth interviews with a purposive sampling strategy targeting parents (N=10), teachers (N=6), and community leaders (N=8) familiar with child-rearing. Results were supplemented by focus group discussions with children (N=9) and teachers (N=8), pile-sort interviews with mothers (N=8) of school-aged children, and direct observations in homes, schools, and community spaces. Behavior problems were largely defined in light of parents’ socialization goals and role expectations for children. Certain physical settings and times were seen to carry greater risk for problematic behavior when children were unsupervised. Parents and other adults attempted to mitigate behavior problems by supervising them and their social interactions, providing for their physical needs, educating them, and through a shared verbal reminding strategy (samjhaune). The findings of our study illustrate the transactional nature of behavior problem development that involves context-specific goals, roles, and concerns that are likely to affect adults’ interpretations and responses to children’s behavior. Ultimately, employing a developmental niche framework will elucidate setting-specific risk and protective factors for culturally compelling intervention strategies. PMID:27173743

MAUVE: A New Strategy for Solving and Grading Physics Problems

NASA Astrophysics Data System (ADS)

Hill, Nicole Breanne

2016-05-01

MAUVE (magnitude, answer, units, variables, and equations) is a framework and rubric to help students and teachers through the process of clearly solving and assessing solutions to introductory physics problems. Success in introductory physics often derives from an understanding of units, a command over dimensional analysis, and good bookkeeping. I developed MAUVE for an introductory-level environmental physics course as an easy-to-remember checklist to help students construct organized and thoughtful solutions to physics problems. Environmental physics is a core physics course for environmental and sustainability science (ESS) majors that teaches principles of radiation, thermodynamics, and mechanics within the context of the environment and sustainable energy systems. ESS student concentrations include environmental biology, applied ecology, biogeochemistry, and natural resources. The MAUVE rubric, inspired by nature, has encouraged my students to produce legible and tactical work, and has significantly clarified the grading process.

Probing student reasoning approaches through the lens of dual-process theories: A case study in buoyancy

NASA Astrophysics Data System (ADS)

Gette, Cody R.; Kryjevskaia, Mila; Stetzer, MacKenzie R.; Heron, Paula R. L.

2018-06-01

A growing body of scholarly work indicates that student performance on physics problems stems from many factors, including relevant conceptual understanding. However, in contexts in which significant conceptual difficulties have been documented via research, it can be difficult to pinpoint and isolate such factors because students' written and interview responses rarely reveal the full richness of their conscious and, perhaps more importantly, subconscious reasoning paths. In this investigation, informed by dual-process theories of reasoning and decision making as well as the theoretical construct of accessibility, we conducted a series of experiments in order to gain greater insight into the factors impacting student performance on the "five-block problem," which has been used in the literature to probe student thinking about buoyancy. In particular, we examined both the impact of problem design (including salient features and cueing) and the impact of targeted instruction focused on density-based arguments for sinking and floating and on neutral buoyancy. The investigation found that instructional modifications designed to remove the strong intuitive appeal of the first-available response led to significantly improved performance, without improving student conceptual understanding of the requisite buoyancy concepts. As such, our findings represent an important first step in identifying systematic strategies for using theories from cognitive science to guide the development and refinement of research-based instructional materials.

Numerical algebraic geometry: a new perspective on gauge and string theories

NASA Astrophysics Data System (ADS)

Mehta, Dhagash; He, Yang-Hui; Hauensteine, Jonathan D.

2012-07-01

There is a rich interplay between algebraic geometry and string and gauge theories which has been recently aided immensely by advances in computational algebra. However, symbolic (Gröbner) methods are severely limited by algorithmic issues such as exponential space complexity and being highly sequential. In this paper, we introduce a novel paradigm of numerical algebraic geometry which in a plethora of situations overcomes these shortcomings. The so-called `embarrassing parallelizability' allows us to solve many problems and extract physical information which elude symbolic methods. We describe the method and then use it to solve various problems arising from physics which could not be otherwise solved.

Academic Failure in Secondary School: The Inter-Related Role of Health Problems and Educational Context.

PubMed

Needham, Belinda L; Crosnoe, Robert; Muller, Chandra

2004-01-01

This study explores whether the interplay of health problems and school environment predicts academic failure, an individual event with consequences for the life course, as well as for society at large. This exploration proceeds in three steps: 1) we examine whether physical and mental health problems are an academic risk factor during secondary school; 2) we investigate the academic mechanisms underlying this risk status; and 3) we explore whether this risk status varies by school context. A series of logistic regressions reveals that self-rated health and emotional distress are both associated with greater likelihood of failing one or more classes in the next year and that absenteeism, trouble with homework, and student-teacher bonding account for much of these associations. Associations of physical and mental health problems with academic failure vary only slightly across schools, however. We discuss the implications of these findings for both research and policy and argue that the examination of overlap among different domains of adolescent functioning can advance the sociological understanding of health, education, and social problems in general.

Biological Sensitivity to Context in Couples: Why Partner Aggression Hurts Some More Than Others

PubMed Central

Lorber, Michael F.; Erlanger, Ann C. Eckardt; Slep, Amy M. Smith

2015-01-01

Objective Cardiovascular reactivity to laboratory stressors was investigated as (a) a moderator of associations of partner aggression with affective functioning, alcohol problems, and parenting, and (b) a consequence of partner aggression. Method Cohabiting adult couples (N = 453) with 3- to 7-year-old children were recruited by random digit dialing and completed questionnaires assessing couple physical aggression, discipline practices, anger, stress, depressive symptoms, and problem alcohol use. Heart rate and blood pressure were measured at rest and in response to laboratory stressors (mental arithmetic and video presentations of family conflict). Results Males’ physical aggression more strongly predicted women’s affective functioning and alcohol problems when the women had greater cardiovascular reactivity. This pattern did not extend to men. Physical victimization was associated with lower cardiovascular reactivity. Conclusions The present results provide partial support for the Biological Sensitivity to Context model of Boyce and Ellis (2005) and suggest that incorporating the moderating influence of biological reactivity may improve the precision of models of the effects of aggression on adult adjustment. PMID:23379267

Computer Systems for Teaching Complex Concepts.

ERIC Educational Resources Information Center

Feurzeig, Wallace

Four Programing systems--Mentor, Stringcomp, Simon, and Logo--were designed and implemented as integral parts of research into the various ways computers may be used for teaching problem-solving concepts and skills. Various instructional contexts, among them medicine, mathematics, physics, and basic problem-solving for elementary school children,…

Extreme value problems without calculus: a good link with geometry and elementary maths

NASA Astrophysics Data System (ADS)

Ganci, Salvatore

2016-11-01

Some classical examples of problem solving, where an extreme value condition is required, are here considered and/or revisited. The search for non-calculus solutions appears pedagogically useful and intriguing as shown through a rich literature. A teacher, who teaches both maths and physics, (as happens in Italian High schools) can find in these kinds of problems a mind stimulating exercise compared with the standard solution obtained by the differential calculus. A good link between the geometric and analytical explanations is so established.

Rarity-weighted richness: a simple and reliable alternative to integer programming and heuristic algorithms for minimum set and maximum coverage problems in conservation planning.

PubMed

Albuquerque, Fabio; Beier, Paul

2015-01-01

Here we report that prioritizing sites in order of rarity-weighted richness (RWR) is a simple, reliable way to identify sites that represent all species in the fewest number of sites (minimum set problem) or to identify sites that represent the largest number of species within a given number of sites (maximum coverage problem). We compared the number of species represented in sites prioritized by RWR to numbers of species represented in sites prioritized by the Zonation software package for 11 datasets in which the size of individual planning units (sites) ranged from <1 ha to 2,500 km2. On average, RWR solutions were more efficient than Zonation solutions. Integer programming remains the only guaranteed way find an optimal solution, and heuristic algorithms remain superior for conservation prioritizations that consider compactness and multiple near-optimal solutions in addition to species representation. But because RWR can be implemented easily and quickly in R or a spreadsheet, it is an attractive alternative to integer programming or heuristic algorithms in some conservation prioritization contexts.

A pilot examination of social context and everyday physical activity among adults receiving Community Mental Health Services.

PubMed

McCormick, B P; Frey, G C; Lee, C-T; Gajic, T; Stamatovic-Gajic, B; Maksimovic, M

2009-03-01

Community mental health center (CMHC) clients include a variety of people with moderate to severe mental illnesses who also report a number of physical health problems. Physical activity (PA) has been identified as one intervention to improve health among this population; however, little is known about the role of social context in PA. The purpose of this study was to examine the role of social context in everyday PA among CMHC clients. Data were collected from CMHC clients in two cultures using accelerometery and experience sampling methods. Data were analyzed using hierarchical linear modeling. Independence in housing nor culture was significantly associated with levels of PA. Being alone was significantly negatively related to PA level. Social isolation appears to be negatively related to PA at the level of everyday life. Physical activity interventions with this population should consider including social components as a part of PA.

Vector Addition: Effect of the Context and Position of the Vectors

NASA Astrophysics Data System (ADS)

Barniol, Pablo; Zavala, Genaro

2010-10-01

In this article we investigate the effect of: 1) the context, and 2) the position of the vectors, on 2D vector addition tasks. We administered a test to 512 students completing introductory physics courses at a private Mexican university. In the first part, we analyze students' responses in three isomorphic problems: displacements, forces, and no physical context. Students were asked to draw two vectors and the vector sum. We analyzed students' procedures detecting the difficulties when drawing the vector addition and proved that the context matters, not only compared to the context-free case but also between the contexts. In the second part, we analyze students' responses with three different arrangements of the sum of two vectors: tail-to-tail, head-to-tail and separated vectors. We compared the frequencies of the errors in the three different positions to deduce students' conceptions in the addition of vectors.

Science modelling in pre-calculus: how to make mathematics problems contextually meaningful

NASA Astrophysics Data System (ADS)

Sokolowski, Andrzej; Yalvac, Bugrahan; Loving, Cathleen

2011-04-01

'Use of mathematical representations to model and interpret physical phenomena and solve problems is one of the major teaching objectives in high school math curriculum' (National Council of Teachers of Mathematics (NCTM), Principles and Standards for School Mathematics, NCTM, Reston, VA, 2000). Commonly used pre-calculus textbooks provide a wide range of application problems. However, these problems focus students' attention on evaluating or solving pre-arranged formulas for given values. The role of scientific content is reduced to provide a background for these problems instead of being sources of data gathering for inducing mathematical tools. Students are neither required to construct mathematical models based on the contexts nor are they asked to validate or discuss the limitations of applied formulas. Using these contexts, the instructor may think that he/she is teaching problem solving, where in reality he/she is teaching algorithms of the mathematical operations (G. Kulm (ed.), New directions for mathematics assessment, in Assessing Higher Order Thinking in Mathematics, Erlbaum, Hillsdale, NJ, 1994, pp. 221-240). Without a thorough representation of the physical phenomena and the mathematical modelling processes undertaken, problem solving unintentionally appears as simple algorithmic operations. In this article, we deconstruct the representations of mathematics problems from selected pre-calculus textbooks and explicate their limitations. We argue that the structure and content of those problems limits students' coherent understanding of mathematical modelling, and this could result in weak student problem-solving skills. Simultaneously, we explore the ways to enhance representations of those mathematical problems, which we have characterized as lacking a meaningful physical context and limiting coherent student understanding. In light of our discussion, we recommend an alternative to strengthen the process of teaching mathematical modelling - utilization of computer-based science simulations. Although there are several exceptional computer-based science simulations designed for mathematics classes (see, e.g. Kinetic Book (http://www.kineticbooks.com/) or Gizmos (http://www.explorelearning.com/)), we concentrate mainly on the PhET Interactive Simulations developed at the University of Colorado at Boulder (http://phet.colorado.edu/) in generating our argument that computer simulations more accurately represent the contextual characteristics of scientific phenomena than their textual descriptions.

An Integrative Perspective on Students' Proportional Reasoning in High School Physics in a West African Context

ERIC Educational Resources Information Center

Akatugba, Ayo Harriet; Wallace, John

2009-01-01

This study examines students' use of proportional reasoning in high school physics problem-solving in a West African school setting. An in-depth, constructivist, and interpretive case study was carried out with six physics students from a co-educational senior secondary school in Nigeria over a period of five months. The study aimed to elicit…

The Relation between Students' Math and Reading Ability and Their Mathematics, Physics, and Chemistry Examination Grades in Secondary Education

ERIC Educational Resources Information Center

Korpershoek, Hanke; Kuyper, Hans; van der Werf, Greetje

2015-01-01

Word problems are math- or science-related problems presented in the context of a story or real-life scenario. Literature suggests that, to solve these problems, advanced reading skills are required, in addition to content-related skills in, for example, mathematics. In the present study, we investigated the relation between students' reading…

Force, velocity, and work: The effects of different contexts on students' understanding of vector concepts using isomorphic problems

NASA Astrophysics Data System (ADS)

Barniol, Pablo; Zavala, Genaro

2014-12-01

In this article we compare students' understanding of vector concepts in problems with no physical context, and with three mechanics contexts: force, velocity, and work. Based on our "Test of Understanding of Vectors," a multiple-choice test presented elsewhere, we designed two isomorphic shorter versions of 12 items each: a test with no physical context, and a test with mechanics contexts. For this study, we administered the items twice to students who were finishing an introductory mechanics course at a large private university in Mexico. The first time, we administered the two 12-item tests to 608 students. In the second, we only tested the items for which we had found differences in students' performances that were difficult to explain, and in this case, we asked them to show their reasoning in written form. In the first administration, we detected no significant difference between the medians obtained in the tests; however, we did identify significant differences in some of the items. For each item we analyze the type of difference found between the tests in the selection of the correct answer, the most common error on each of the tests, and the differences in the selection of incorrect answers. We also investigate the causes of the different context effects. Based on these analyses, we establish specific recommendations for the instruction of vector concepts in an introductory mechanics course. In the Supplemental Material we include both tests for other researchers studying vector learning, and for physics teachers who teach this material.

A case study of analyzing 11th graders’ problem solving ability on heat and temperature topic

NASA Astrophysics Data System (ADS)

Yulianawati, D.; Muslim; Hasanah, L.; Samsudin, A.

2018-05-01

Problem solving ability must be owned by students after the process of physics learning so that the concept of physics becomes meaningful. Consequently, the research aims to describe their problem solving ability. Metacognition is contributed to physics learning to the success of students in solving problems. This research has already been implemented to 37 science students (30 women and 7 men) of eleventh grade from one of the secondary schools in Bandung. The research methods utilized the single case study with embedded research design. The instrument is Heat and Temperature Problem Solving Ability Test (HT-PSAT) which consists of twelve questions from three context problems. The result shows that the average value of the test is 8.27 out of the maximum total value of 36. In conclusion, eleventh graders’ problem-solving ability is still under expected. The implication of the findings is able to create learning situations which are probably developing students to embrace better problem solving ability.

Motivational valence alters memory formation without altering exploration of a real-life spatial environment.

PubMed

Chiew, Kimberly S; Hashemi, Jordan; Gans, Lee K; Lerebours, Laura; Clement, Nathaniel J; Vu, Mai-Anh T; Sapiro, Guillermo; Heller, Nicole E; Adcock, R Alison

2018-01-01

Volitional exploration and learning are key to adaptive behavior, yet their characterization remains a complex problem for cognitive science. Exploration has been posited as a mechanism by which motivation promotes memory, but this relationship is not well-understood, in part because novel stimuli that motivate exploration also reliably elicit changes in neuromodulatory brain systems that directly alter memory formation, via effects on neural plasticity. To deconfound interrelationships between motivation, exploration, and memory formation we manipulated motivational state prior to entering a spatial context, measured exploratory responses to the context and novel stimuli within it, and then examined motivation and exploration as predictors of memory outcomes. To elicit spontaneous exploration, we used the physical space of an art exhibit with affectively rich content; we expected motivated exploration and memory to reflect multiple factors, including not only motivational valence, but also individual differences. Motivation was manipulated via an introductory statement framing exhibit themes in terms of Promotion- or Prevention-oriented goals. Participants explored the exhibit while being tracked by video. They returned 24 hours later for recall and spatial memory tests, followed by measures of motivation, personality, and relevant attitude variables. Promotion and Prevention condition participants did not differ in terms of group-level exploration time or memory metrics, suggesting similar motivation to explore under both framing contexts. However, exploratory behavior and memory outcomes were significantly more closely related under Promotion than Prevention, indicating that Prevention framing disrupted expected depth-of-encoding effects. Additionally, while trait measures predicted exploration similarly across framing conditions, traits interacted with motivational framing context and facial affect to predict memory outcomes. This novel characterization of motivated learning implies that dissociable behavioral and biological mechanisms, here varying as a function of valence, contribute to memory outcomes in complex, real-life environments.

Motivational valence alters memory formation without altering exploration of a real-life spatial environment

PubMed Central

Hashemi, Jordan; Gans, Lee K.; Lerebours, Laura; Clement, Nathaniel J.; Vu, Mai-Anh T.; Sapiro, Guillermo; Heller, Nicole E.; Adcock, R. Alison

2018-01-01

Volitional exploration and learning are key to adaptive behavior, yet their characterization remains a complex problem for cognitive science. Exploration has been posited as a mechanism by which motivation promotes memory, but this relationship is not well-understood, in part because novel stimuli that motivate exploration also reliably elicit changes in neuromodulatory brain systems that directly alter memory formation, via effects on neural plasticity. To deconfound interrelationships between motivation, exploration, and memory formation we manipulated motivational state prior to entering a spatial context, measured exploratory responses to the context and novel stimuli within it, and then examined motivation and exploration as predictors of memory outcomes. To elicit spontaneous exploration, we used the physical space of an art exhibit with affectively rich content; we expected motivated exploration and memory to reflect multiple factors, including not only motivational valence, but also individual differences. Motivation was manipulated via an introductory statement framing exhibit themes in terms of Promotion- or Prevention-oriented goals. Participants explored the exhibit while being tracked by video. They returned 24 hours later for recall and spatial memory tests, followed by measures of motivation, personality, and relevant attitude variables. Promotion and Prevention condition participants did not differ in terms of group-level exploration time or memory metrics, suggesting similar motivation to explore under both framing contexts. However, exploratory behavior and memory outcomes were significantly more closely related under Promotion than Prevention, indicating that Prevention framing disrupted expected depth-of-encoding effects. Additionally, while trait measures predicted exploration similarly across framing conditions, traits interacted with motivational framing context and facial affect to predict memory outcomes. This novel characterization of motivated learning implies that dissociable behavioral and biological mechanisms, here varying as a function of valence, contribute to memory outcomes in complex, real-life environments. PMID:29558526

Adding Value to Force Diagrams: Representing Relative Force Magnitudes

ERIC Educational Resources Information Center

Wendel, Paul

2011-01-01

Nearly all physics instructors recognize the instructional value of force diagrams, and this journal has published several collections of exercises to improve student skill in this area. Yet some instructors worry that too few students perceive the conceptual and problem-solving utility of force diagrams, and over recent years a rich variety of…

Physics and Hard Disk Drives-A Career in Industry

NASA Astrophysics Data System (ADS)

Lambert, Steven

2014-03-01

I will participate in a panel discussion about ``Career Opportunities for Physicists.'' I enjoyed 27 years doing technology development and product support in the hard disk drive business. My PhD in low temperature physics was excellent training for this career since I learned how to work in a lab, analyze data, write and present technical information, and define experiments that got to the heart of a problem. An academic position did not appeal to me because I had no passion to pursue a particular topic in basic physics. My work in industry provided an unending stream of challenging problems to solve, and it was a rich and rewarding experience. I'm now employed by the APS to focus on our interactions with physicists in industry. I welcome the chance to share my industrial experience with students, post-docs, and others who are making decisions about their career path. Industrial Physics Fellow, APS Headquarters.

Patellar Tendinopathy

PubMed Central

Schwartz, Aaron; Watson, Jonathan N.; Hutchinson, Mark R.

2015-01-01

Context: Patellar tendinopathy is a common condition. There are a wide variety of treatment options available, the majority of which are nonoperative. No consensus exists on the optimal method of treatment. Evidence Acquisition: PubMed spanning 1962-2014. Study Design: Clinical review. Level of Evidence: Level 4. Results: The majority of cases resolve with nonoperative therapy: rest, physical therapy with eccentric exercises, cryotherapy, anti-inflammatories, corticosteroid injections, extracorporeal shockwave therapy, glyceryl trinitrate, platelet-rich plasma injections, and ultrasound-guided sclerosis. Refractory cases may require either open or arthroscopic debridement of the patellar tendon. Corticosteroid injections provide short-term pain relief but increase risk of tendon rupture. Anti-inflammatories and injectable agents have shown mixed results. Surgical treatment is effective in many refractory cases unresponsive to nonoperative modalities. Conclusion: Physical therapy with an eccentric exercise program is the mainstay of treatment for patellar tendinopathy. Platelet-rich plasma has demonstrated mixed results; evidence-based recommendations on its efficacy cannot be made. In the event that nonoperative treatment fails, surgical intervention has produced good to excellent outcomes in the majority of patients. PMID:26502416

Who Helps You? Self and Other Sources of Support among Youth in Japan and the USA

ERIC Educational Resources Information Center

Crystal, David S.; Kakinuma, Miki; DeBell, Matthew; Azuma, Hiroshi; Miyashita, Takahiro

2008-01-01

Japanese and U.S. sixth, eighth, and tenth graders (N = 2141) responded to questionnaires asking whom they depended on in six contexts of need. These contexts were: morning awakening, physical illness, emotional upset, help with homework, causing a problem, and guidance in extracurricular activities. Findings indicated that, relative to culture,…

Video Analysis of a Plucked String: An Example of Problem-based Learning

NASA Astrophysics Data System (ADS)

Wentworth, Christopher D.; Buse, Eric

2009-11-01

Problem-based learning is a teaching methodology that grounds learning within the context of solving a real problem. Typically the problem initiates learning of concepts rather than simply being an application of the concept, and students take the lead in identifying what must be developed to solve the problem. Problem-based learning in upper-level physics courses can be challenging, because of the time and financial requirements necessary to generate real data. Here, we present a problem that motivates learning about partial differential equations and their solution in a mathematical methods for physics course. Students study a plucked elastic cord using high speed digital video. After creating video clips of the cord motion under different tensions they are asked to create a mathematical model. Ultimately, students develop and solve a model that includes damping effects that are clearly visible in the videos. The digital video files used in this project are available on the web at http://physics.doane.edu .

Gravity, Magnetism, and "Down": Non-Physics College Students' Conceptions of Gravity

ERIC Educational Resources Information Center

Asghar, Anila; Libarkin, Julie C.

2010-01-01

This study investigates how students enrolled in entry-level geology, most of whom would graduate from college without university-level physics courses, thought about and applied the concept of gravity while solving problems concerning gravity. The repercussions of students' gravity concepts are then considered in the context of non-physics…

Approaches to Interactive Video Anchors in Problem-based Science Learning

NASA Astrophysics Data System (ADS)

Kumar, David Devraj

2010-02-01

This paper is an invited adaptation of the IEEE Education Society Distinguished Lecture Approaches to Interactive Video Anchors in Problem-Based Science Learning. Interactive video anchors have a cognitive theory base, and they help to enlarge the context of learning with information-rich real-world situations. Carefully selected movie clips and custom-developed regular videos and virtual simulations have been successfully used as anchors in problem-based science learning. Examples discussed include a range of situations such as Indiana Jones tackling a trap, a teenager misrepresenting lead for gold, an agriculture inspection at the US border, counterintuitive events, analyzing a river ecosystem for pollution, and finding the cause of illness in a nineteenth century river city. Suggestions for teachers are provided.

From entropy-maximization to equality-maximization: Gauss, Laplace, Pareto, and Subbotin

NASA Astrophysics Data System (ADS)

Eliazar, Iddo

2014-12-01

The entropy-maximization paradigm of statistical physics is well known to generate the omnipresent Gauss law. In this paper we establish an analogous socioeconomic model which maximizes social equality, rather than physical disorder, in the context of the distributions of income and wealth in human societies. We show that-on a logarithmic scale-the Laplace law is the socioeconomic equality-maximizing counterpart of the physical entropy-maximizing Gauss law, and that this law manifests an optimized balance between two opposing forces: (i) the rich and powerful, striving to amass ever more wealth, and thus to increase social inequality; and (ii) the masses, struggling to form more egalitarian societies, and thus to increase social equality. Our results lead from log-Gauss statistics to log-Laplace statistics, yield Paretian power-law tails of income and wealth distributions, and show how the emergence of a middle-class depends on the underlying levels of socioeconomic inequality and variability. Also, in the context of asset-prices with Laplace-distributed returns, our results imply that financial markets generate an optimized balance between risk and predictability.

Using Mathematics and Engineering to Solve Problems in Secondary Level Biology

ERIC Educational Resources Information Center

Cox, Charles; Reynolds, Birdy; Schunn, Christian; Schuchardt, Anita

2016-01-01

There are strong classroom ties between mathematics and the sciences of physics and chemistry, but those ties seem weaker between mathematics and biology. Practicing biologists realize both that there are interesting mathematics problems in biology, and that viewing classroom biology in the context of another discipline could support students'…

Sharing the Benefits of Research Fairly: Two Approaches

PubMed Central

Millum, Joseph

2016-01-01

Research projects sponsored by rich countries or companies and carried out in developing countries are frequently described as exploitative. One important debate about the prevention of exploitation in research centers on whether and how clinical research in developing countries should be responsive to local health problems. This paper analyses the responsiveness debate and draws out more general lessons for how policy makers can prevent exploitation in various research contexts. There are two independent ways to do this in the face of entrenched power differences: to impose restrictions on the content of benefit-sharing arrangements, and to institute independent effective oversight. Which method should be chosen is highly dependent on context. PMID:21947808

The influence of mastery on mother's health in middle years: Moderating role of stressful life context.

PubMed

King, Victoria; Wickrama, K A S; Klopack, Erick; Lorenz, Frederick O

2018-06-07

Using data from 416 middle-aged mothers gathered over the course of a decade, this study examined the influence of mastery trajectories (the initial level and change), on change in physical health. Mastery is defined as one's ability to control and influence his/her life and environment to reach a desired outcome or goal. Both the initial level and change in mastery from 1991 to 1994 were associated with decreased physical health problems over the middle years (1991-2001). Contextual moderation of this association by stressful life contexts including negative life events and work-family conflict was investigated. Moderation analysis showed that under conditions of low contextual life stressors, the level and increase in mastery significantly contributed to decreases in physical health problems in middle-aged mothers. Alternatively, conditions of high contextual life stressors inhibited the ability of mastery to influence physical health of mothers, suggesting that the positive health impact of mastery on physical health is mitigated by stressful life experiences. Implications for the need to maintain important personal resources, such as mastery, during times of stress are discussed. Copyright © 2018 John Wiley & Sons, Ltd.

Maxwell-Faraday Stresses in Electromagnetic Fields and the Self-Force on a Uniformly Accelerating Point Charge

ERIC Educational Resources Information Center

Rowland, D. R.

2007-01-01

The physical analysis of a uniformly accelerating point charge provides a rich problem to explore in advanced courses in electrodynamics and relativity since it brings together fundamental concepts in relation to electromagnetic radiation, Einstein's equivalence principle and the inertial mass of field energy in ways that reveal subtleties in each…

The ecocultural context and child behavior problems: A qualitative analysis in rural Nepal.

PubMed

Burkey, Matthew D; Ghimire, Lajina; Adhikari, Ramesh Prasad; Wissow, Lawrence S; Jordans, Mark J D; Kohrt, Brandon A

2016-06-01

Commonly used paradigms for studying child psychopathology emphasize individual-level factors and often neglect the role of context in shaping risk and protective factors among children, families, and communities. To address this gap, we evaluated influences of ecocultural contextual factors on definitions, development of, and responses to child behavior problems and examined how contextual knowledge can inform culturally responsive interventions. We drew on Super and Harkness' "developmental niche" framework to evaluate the influences of physical and social settings, childcare customs and practices, and parental ethnotheories on the definitions, development of, and responses to child behavior problems in a community in rural Nepal. Data were collected between February and October 2014 through in-depth interviews with a purposive sampling strategy targeting parents (N = 10), teachers (N = 6), and community leaders (N = 8) familiar with child-rearing. Results were supplemented by focus group discussions with children (N = 9) and teachers (N = 8), pile-sort interviews with mothers (N = 8) of school-aged children, and direct observations in homes, schools, and community spaces. Behavior problems were largely defined in light of parents' socialization goals and role expectations for children. Certain physical settings and times were seen to carry greater risk for problematic behavior when children were unsupervised. Parents and other adults attempted to mitigate behavior problems by supervising them and their social interactions, providing for their physical needs, educating them, and through a shared verbal reminding strategy (samjhaune). The findings of our study illustrate the transactional nature of behavior problem development that involves context-specific goals, roles, and concerns that are likely to affect adults' interpretations and responses to children's behavior. Ultimately, employing a developmental niche framework will elucidate setting-specific risk and protective factors for culturally compelling intervention strategies. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Place of Learning Quantum Theory in Physics Teacher Education: Motivational Elements Arising from the Context

ERIC Educational Resources Information Center

Körhasan, Nilüfer Didis

2015-01-01

Quantum theory is one of the most successful theories in physics. Because of its abstract, mathematical, and counter-intuitive nature, many students have problems learning the theory, just as teachers experience difficulty in teaching it. Pedagogical research on quantum theory has mainly focused on cognitive issues. However, affective issues about…

The Social Psychology of Perception Experiments: Hills, Backpacks, Glucose, and the Problem of Generalizability

ERIC Educational Resources Information Center

Durgin, Frank H.; Klein, Brennan; Spiegel, Ariana; Strawser, Cassandra J.; Williams, Morgan

2012-01-01

Experiments take place in a physical environment but also a social environment. Generalizability from experimental manipulations to more typical contexts may be limited by violations of ecological validity with respect to either the physical or the social environment. A replication and extension of a recent study (a blood glucose manipulation) was…

Biology Education & Health Education: A School Garden as a Location of Learning & Well-Being

ERIC Educational Resources Information Center

Retzlaff-Fürst, Carolin

2016-01-01

Children and adolescents spend a large part of their day at school. Physical and mental problems result from physical inactivity, sitting positions at work and "indoor lifestyle" (WHO 2004). Therefore, health education is a major topic in school. Biology classes (scholastic) can make an important contribution in this context. Health as a…

What Physicist Mean By The Equals Sign In Undergraduate Education

NASA Astrophysics Data System (ADS)

Zohrabi Alaee, Dina; Kornick, Kellianne; Sayre, Eleanor C.; Franklin, Scott V.

2017-01-01

Mathematical concepts and tools have an important role in physics. Faculties want students to think critically about mathematics and the underlying fundamental concepts, rather than simply memorizing a series of equations and answers. The equals sign - ubiquitous in problem solving - carries different conceptual meaning depending on how it is used; this meaning is deeply tied to cultural practices in problem solving in physics. We use symbolic forms to investigate the conceptual and cultural meanings of the equals sign across physics contexts. We built and validated a rubric to classify the ways that physics students use the equals sign in their written work. Our categories are causality, assignments, definitional, balancing, and just math. We analyze students' use of the equals sign in their written homework and exam solutions in an upper-division electrostatics course. We correlate the kinds of equal signs within problem solutions with the difficulty of the problem. We compare they ways students use the equals sign to their course lectures and textbook.

Maltreatment and Emotional and Behavioral Problems in Chinese Children With and Without Oppositional Defiant Disorder: The Mediating Role of the Parent-Child Relationship.

PubMed

Li, Longfeng; Lin, Xiuyun; Chi, Peilian; Heath, Melissa Allen; Fang, Xiaoyi; Du, Hongfei; Wang, Zhonghui

2016-11-01

Maltreatment has negative effects on the parent-child relationship and the emotional and behavioral development of children. The current study aimed to examine the associations among maltreatment, parent-child relationship, and emotional and behavioral problems in Chinese children with or without oppositional defiant disorder (ODD). Participants in the study included 259 children with ODD and their 269 non-ODD counterparts from northern, eastern, and southwestern China. We also collected data from their teachers and fathers or mothers. The results showed that ODD children suffered more maltreatment and had more emotional and behavioral problems than their non-ODD peers. For all children (both ODD and non-ODD children), emotional abuse predicted emotional problems but not behavioral problems. Physical abuse predicted behavioral problems but not emotional problems. Parent-child relationship mediated the effects of emotional abuse and physical abuse on emotional problems among ODD children but not among non-ODD children. Implications for prevention of emotional and physical abuse and ODD in the Chinese cultural context are discussed. © The Author(s) 2016.

Impact of Problem-Based Learning to Students and Teachers

ERIC Educational Resources Information Center

Hirca, Necati

2011-01-01

The Ministry of National Education of Turkey has decided to give up traditional methods to be used in the classes and to develop a new secondary school curriculum based on Context-Based Learning (CBL) in 2007. This paper discusses integrating Problem-Based Learning (PBL) tasks into the new physics curriculum in Turkey. A brief overview of a…

Challenges and Responses to the Vulnerability of Families in a Preschool Context

ERIC Educational Resources Information Center

Turnšek, Nada; Škraban, Olga Poljšak; Razpotnik, Špela; Pavel, Jana Rapuš

2016-01-01

Problems in vulnerable families are multilayered and include the intersection of physical, psychosocial and other forms of distress. The multidimensional nature of the problems of these families is closely linked to the fact that there are many institutions in the field of education, social welfare, health care and others, in which treatment and…

Major galaxy mergers and the growth of supermassive black holes in quasars.

PubMed

Treister, Ezequiel; Natarajan, Priyamvada; Sanders, David B; Urry, C Megan; Schawinski, Kevin; Kartaltepe, Jeyhan

2010-04-30

Despite observed strong correlations between central supermassive black holes (SMBHs) and star formation in galactic nuclei, uncertainties exist in our understanding of their coupling. We present observations of the ratio of heavily obscured to unobscured quasars as a function of cosmic epoch up to z congruent with 3 and show that a simple physical model describing mergers of massive, gas-rich galaxies matches these observations. In the context of this model, every obscured and unobscured quasar represents two distinct phases that result from a massive galaxy merger event. Much of the mass growth of the SMBH occurs during the heavily obscured phase. These observations provide additional evidence for a causal link between gas-rich galaxy mergers, accretion onto the nuclear SMBH, and coeval star formation.

Operational method of solution of linear non-integer ordinary and partial differential equations.

PubMed

Zhukovsky, K V

2016-01-01

We propose operational method with recourse to generalized forms of orthogonal polynomials for solution of a variety of differential equations of mathematical physics. Operational definitions of generalized families of orthogonal polynomials are used in this context. Integral transforms and the operational exponent together with some special functions are also employed in the solutions. The examples of solution of physical problems, related to such problems as the heat propagation in various models, evolutional processes, Black-Scholes-like equations etc. are demonstrated by the operational technique.

Learning stoichiometry: A comparison of text and multimedia instructional formats

NASA Astrophysics Data System (ADS)

Evans, Karen L.

Even after multiple instructional opportunities, first year college chemistry students are often unable to apply stoichiometry knowledge in equilibrium and acid-base chemistry problem solving. Cognitive research findings suggest that for learning to be meaningful, learners need to actively construct their own knowledge by integrating new information into, and reorganizing, their prior understandings. Scaffolded inquiry in which facts, procedures, and principles are introduced as needed within the context of authentic problem solving may provide the practice and encoding opportunities necessary for construction of a memorable and usable knowledge base. The dynamic and interactive capabilities of online technology may facilitate stoichiometry instruction that promotes this meaningful learning. Entering college freshmen were randomly assigned to either a technology-rich or text-only set of cognitively informed stoichiometry review materials. Analysis of posttest scores revealed a significant but small difference in the performance of the two treatment groups, with the technology-rich group having the advantage. Both SAT and gender, however, explained more of the variability in the scores. Analysis of the posttest scores from the technology-rich treatment group revealed that the degree of interaction with the Virtual Lab simulation was significantly related to posttest performance and subsumed any effect of prior knowledge as measured by SAT scores. Future users of the online course should be encouraged to engage with the problem-solving opportunities provided by the Virtual Lab simulation through either explicit instruction and/or implementation of some level of program control within the course's navigational features.

Teaching with Data: Resources for Designing Effective Activities

NASA Astrophysics Data System (ADS)

Manduca, C. A.; Mogk, D. W.

2004-12-01

Faculty and teachers understand the power of engaging students directly with data and are tremendously enthusiastic about the possibilities of incorporating data-rich activities in their teaching. This enthusiasm reflects the desire to empower students to solve problems, to place learning in an exciting and authentic real world context that motivates learning, and to illuminate students' understanding of the nature of science. Data-rich activities provide abundant opportunities to motivate students to engage in learning, to integrate learning of facts and skills, and to build on prior knowledge. These are all factors that are identified by research as fundamental to the learning process (How People Learn, 1999, NRC). Data-rich activities can place learning in a context that enhances students' ability to use information in new situations. Seismological data offer many opportunities due to students' familiarity with and interest in earthquakes, and its use to probe the internal structure of the Earth. Three of the most challenging aspects of teaching with data are 1) presenting data with analysis tools that can be quickly mastered, 2) designing learning activities to match the level of student expertise with data analysis and critical thinking, and 3) creating assessments that capture learning beyond factual recall. The Using Data in the Classroom website (serc.carleton.edu/usingdata) helps faculty excel at teaching with data by providing easy access to a wide range of data, discussion of the ways in which data can be effectively used in the classroom, examples of data-rich activities at a variety of educational levels across a range of geoscience topics, and references to pedagogic information. The Earth Exploration Toolbook (serc.Carleton.edu/eet) supports teachers' use of particular datasets and tools by providing step-by-step instructions in the context of an example. The Investigating Earthquakes chapter focuses specifically on use of GIS to analyze USGS earthquake data (serc.Carleton.edu/eet/earthquakes).

Ecological Factors in Human Development.

PubMed

Cross, William E

2017-05-01

Urie Bronfenbrenner (1992) helped developmental psychologists comprehend and define "context" as a rich, thick multidimensional construct. His ecological systems theory consists of five layers, and within each layer are developmental processes unique to each layer. The four articles in this section limit the exploration of context to the three innermost systems: the individual plus micro- and macrolayers. Rather than examine both the physical features and processes, the articles tend to focus solely on processes associated with a niche. Processes explored include social identity development, social network dynamics, peer influences, and school-based friendship patterns. The works tend to extend the generalization of extant theory to the developmental experience of various minority group experiences. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

Exploring the Use of Electroencephalography to Gather Objective Evidence of Cognitive Processing During Problem Solving

NASA Astrophysics Data System (ADS)

Delahunty, Thomas; Seery, Niall; Lynch, Raymond

2018-04-01

Currently, there is significant interest being directed towards the development of STEM education to meet economic and societal demands. While economic concerns can be a powerful driving force in advancing the STEM agenda, care must be taken that such economic imperative does not promote research approaches that overemphasize pragmatic application at the expense of augmenting the fundamental knowledge base of the discipline. This can be seen in the predominance of studies investigating problem solving approaches and procedures, while neglecting representational and conceptual processes, within the literature. Complementing concerns about STEM graduates' problem solving capabilities, raised within the pertinent literature, this paper discusses a novel methodological approach aimed at investigating the cognitive elements of problem conceptualization. The intention is to demonstrate a novel method of data collection that overcomes some of the limitations cited in classic problem solving research while balancing a search for fundamental understanding with the possibility of application. The methodology described in this study employs an electroencephalographic (EEG) headset, as part of a mixed methods approach, to gather objective evidence of students' cognitive processing during problem solving epochs. The method described provides rich evidence of students' cognitive representations of problems during episodes of applied reasoning. The reliability and validity of the EEG method is supported by the stability of the findings across the triangulated data sources. The paper presents a novel method in the context of research within STEM education and demonstrates an effective procedure for gathering rich evidence of cognitive processing during the early stages of problem conceptualization.

Tails and Ties. Editorial

NASA Astrophysics Data System (ADS)

Carbone, A.; Kaniadakis, G.; Scarfone, A. M.

2007-05-01

The study of behavioural and social phenomena has experienced a surge of interest over the last decade. One reason for this great attention is the huge amount of high quality data made available by the internet technologies. The many studies spanning concepts and problems belonging to economics, biology, ecology, physics and computer science, clearly indicates increasing interdisciplinary cross-fertilization, commonalities in the different approaches and communication across these disciplines. This issue of The European Physical Journal B is devoted to the interdisciplinary field of Sociophysics. The papers have been selected from the contributions presented at the 5th International Conference on “Applications of Physics in Financial Analysis" (APFA5) held in Torino from June 29th to July 1st 2006 ( http://www.polito.it/apfa5). The synergy and richness of results obtained from the investigation of problems belonging to the area of complexity science from different perspectives clearly indicates future directions and research methodologies in this field.

Flare physics at high energies

NASA Technical Reports Server (NTRS)

Ramaty, R.

1990-01-01

High-energy processes, involving a rich variety of accelerated particle phenomena, lie at the core of the solar flare problem. The most direct manifestation of these processes are high-energy radiations, gamma rays, hard X-rays and neutrons, as well as the accelerated particles themselves, which can be detected in interplanetary space. In the study of astrophysics from the moon, the understanding of these processes should have great importance. The inner solar system environment is strongly influenced by activity on the sun; the physics of solar flares is of great intrinsic interest; and much high-energy astrophysics can be learned from investigations of flare physics at high energies.

Health problems in adolescents with alcohol use disorders: self-report, liver injury, and physical examination findings and correlates.

PubMed

Clark, D B; Lynch, K G; Donovan, J E; Block, G D

2001-09-01

Although adolescent alcohol consumption has been found to be positively correlated with self-reported health problems, few studies have examined other health indicators. This study compared adolescents with alcohol use disorders (AUDs) and a community reference group on self-reported health problems, serum liver enzymes, and physical examination findings. The relevance of negative emotionality to understanding these health problems was also investigated. The subjects were adolescents with AUDs recruited from clinical programs and classified as having DSM-IV alcohol dependence (n = 71) or alcohol abuse (n = 57) and reference adolescents without AUDs recruited from community sources (n = 131). The assessment of health status included self-reported health problems in 15 areas; serum liver enzyme assays, including gamma-glutamyl transpeptidase, alanine aminotransferase, and aspartate aminotransferase; and physical examination findings. Negative emotionality was determined by systematically combining scores from the Hamilton Anxiety Rating Scale, the Beck Depression Inventory, the Child Behavior Checklist, and the Multidimensional Personality Questionnaire. Adolescent AUDs were associated with more self-reported health problems, higher gamma-glutamyl transpeptidase and alanine aminotransferase levels, and more physical examination abnormalities. Negative emotionality was highly correlated with self-reported health problems, mediated the relationship between AUDs and self-reported health problems, and was not correlated with serum liver enzyme levels or physical examination abnormalities. These results indicated that AUDs during adolescence were associated with health problems, including modest but demonstrable liver injury. Self-reported health problems were probably best understood, in this context, as a negative emotionality manifestation.

The Influence of Accelerator Science on Physics Research

NASA Astrophysics Data System (ADS)

Haussecker, Enzo F.; Chao, Alexander W.

2011-06-01

We evaluate accelerator science in the context of its contributions to the physics community. We address the problem of quantifying these contributions and present a scheme for a numerical evaluation of them. We show by using a statistical sample of important developments in modern physics that accelerator science has influenced 28% of post-1938 physicists and also 28% of post-1938 physics research. We also examine how the influence of accelerator science has evolved over time, and show that on average it has contributed to a physics Nobel Prize-winning research every 2.9 years.

What works with worked examples: Extending self-explanation and analogical comparison to synthesis problems

NASA Astrophysics Data System (ADS)

Badeau, Ryan; White, Daniel R.; Ibrahim, Bashirah; Ding, Lin; Heckler, Andrew F.

2017-12-01

The ability to solve physics problems that require multiple concepts from across the physics curriculum—"synthesis" problems—is often a goal of physics instruction. Three experiments were designed to evaluate the effectiveness of two instructional methods employing worked examples on student performance with synthesis problems; these instructional techniques, analogical comparison and self-explanation, have previously been studied primarily in the context of single-concept problems. Across three experiments with students from introductory calculus-based physics courses, both self-explanation and certain kinds of analogical comparison of worked examples significantly improved student performance on a target synthesis problem, with distinct improvements in recognition of the relevant concepts. More specifically, analogical comparison significantly improved student performance when the comparisons were invoked between worked synthesis examples. In contrast, similar comparisons between corresponding pairs of worked single-concept examples did not significantly improve performance. On a more complicated synthesis problem, self-explanation was significantly more effective than analogical comparison, potentially due to differences in how successfully students encoded the full structure of the worked examples. Finally, we find that the two techniques can be combined for additional benefit, with the trade-off of slightly more time on task.

Answer First: Applying the Heuristic-Analytic Theory of Reasoning to Examine Student Intuitive Thinking in the Context of Physics

ERIC Educational Resources Information Center

Kryjevskaia, Mila; Stetzer, MacKenzie R.; Grosz, Nathaniel

2014-01-01

We have applied the heuristic-analytic theory of reasoning to interpret inconsistencies in student reasoning approaches to physics problems. This study was motivated by an emerging body of evidence that suggests that student conceptual and reasoning competence demonstrated on one task often fails to be exhibited on another. Indeed, even after…

Authentic Research in the Classroom: NITARP Teachers Connect Astronomy with NGSS.

NASA Astrophysics Data System (ADS)

Pruett, Lee; Gibbs, John; Palmer, Robert; Young, Diedre; Gorjian, Varoujan

2016-01-01

The NASA/IPAC Teacher Archive Research Program (NITARP) uses authentic astronomical research to bring the Next Generation Science Standards (NGSS) into the classroom. The creation of the NGSS was a collaborative effort between teams composed of teachers, scientists and other professionals from twenty-six states. These standards provide a framework for the change in how science is taught at all levels from kindergarten to twelfth grade in participating states. Scientific concepts are grouped into broad categories (physical, biological and earth sciences), and call for an interdisciplinary approach to content, along with the integration of engineering practices into the curriculum. This approach to the teaching of science has led educators to place more emphasis on authentic learning and problem-solving in their curricula. Project-based learning is a strategy that can effectively allow students to learn core scientific concepts within the context of a focused and complex scientific problem.The NASA/IPAC Teacher Archive Research Program (NITARP) pairs teams of teachers and students with NASA astronomers. These teams are immersed in an astronomy research project over the course of the year, and are responsible for writing a project proposal, doing original research and presenting that research at a professional conference. The students who are involved in the NITARP research are provided with a rich hands-on experience that both exposes them to a deep understanding of an astronomical problem (and the core physics and math behind it), as well as the process of doing real science. The NITARP program offers a unique opportunity to bring project-based learning into K-12 science classrooms. We will highlight the ways in which this program has been implemented in classrooms across the country, as well as the connections to the NGSS.This research was made possible through the NASA/IPAC Teacher Archive Research Program (NITARP) and was funded by NASA Astrophysics Data Program.

New tools for investigating student learning in upper-division electrostatics

NASA Astrophysics Data System (ADS)

Wilcox, Bethany R.

Student learning in upper-division physics courses is a growing area of research in the field of Physics Education. Developing effective new curricular materials and pedagogical techniques to improve student learning in upper-division courses requires knowledge of both what material students struggle with and what curricular approaches help to overcome these struggles. To facilitate the course transformation process for one specific content area --- upper-division electrostatics --- this thesis presents two new methodological tools: (1) an analytical framework designed to investigate students' struggles with the advanced physics content and mathematically sophisticated tools/techniques required at the junior and senior level, and (2) a new multiple-response conceptual assessment designed to measure student learning and assess the effectiveness of different curricular approaches. We first describe the development and theoretical grounding of a new analytical framework designed to characterize how students use mathematical tools and techniques during physics problem solving. We apply this framework to investigate student difficulties with three specific mathematical tools used in upper-division electrostatics: multivariable integration in the context of Coulomb's law, the Dirac delta function in the context of expressing volume charge densities, and separation of variables as a technique to solve Laplace's equation. We find a number of common themes in students' difficulties around these mathematical tools including: recognizing when a particular mathematical tool is appropriate for a given physics problem, mapping between the specific physical context and the formal mathematical structures, and reflecting spontaneously on the solution to a physics problem to gain physical insight or ensure consistency with expected results. We then describe the development of a novel, multiple-response version of an existing conceptual assessment in upper-division electrostatics courses. The goal of this new version is to provide an easily-graded electrostatics assessment that can potentially be implemented to investigate student learning on a large scale. We show that student performance on the new multiple-response version exhibits a significant degree of consistency with performance on the free-response version, and that it continues to provide significant insight into student reasoning and student difficulties. Moreover, we demonstrate that the new assessment is both valid and reliable using data from upper-division physics students at multiple institutions. Overall, the work described in this thesis represents a significant contribution to the methodological tools available to researchers and instructors interested in improving student learning at the upper-division level.

No space for girliness in physics: understanding and overcoming the masculinity of physics

NASA Astrophysics Data System (ADS)

Götschel, Helene

2014-06-01

Allison Gonsalves' article on "women doctoral students' positioning around discourses of gender and competence in physics" explores narratives of Canadian women physicists concerning their strategies to gain recognition as physicists. In my response to her rewarding and inspiring analysis I will reflect on her findings and arguments and put them into a broader context of research in gender and physics. In addition to her promising strategies to make physics attractive and welcoming to all genders I want to stress two more aspects of the tricky problem: diversity and contextuality of physics.

The Neural Basis of Risky Choice with Affective Outcomes

PubMed Central

Suter, Renata S.; Pachur, Thorsten; Hertwig, Ralph; Endestad, Tor; Biele, Guido

2015-01-01

Both normative and many descriptive theories of decision making under risk are based on the notion that outcomes are weighted by their probability, with subsequent maximization of the (subjective) expected outcome. Numerous investigations from psychology, economics, and neuroscience have produced evidence consistent with this notion. However, this research has typically investigated choices involving relatively affect-poor, monetary outcomes. We compared choice in relatively affect-poor, monetary lottery problems with choice in relatively affect-rich medical decision problems. Computational modeling of behavioral data and model-based neuroimaging analyses provide converging evidence for substantial differences in the respective decision mechanisms. Relative to affect-poor choices, affect-rich choices yielded a more strongly curved probability weighting function of cumulative prospect theory, thus signaling that the psychological impact of probabilities is strongly diminished for affect-rich outcomes. Examining task-dependent brain activation, we identified a region-by-condition interaction indicating qualitative differences of activation between affect-rich and affect-poor choices. Moreover, brain activation in regions that were more active during affect-poor choices (e.g., the supramarginal gyrus) correlated with individual trial-by-trial decision weights, indicating that these regions reflect processing of probabilities. Formal reverse inference Neurosynth meta-analyses suggested that whereas affect-poor choices seem to be based on brain mechanisms for calculative processes, affect-rich choices are driven by the representation of outcomes’ emotional value and autobiographical memories associated with them. These results provide evidence that the traditional notion of expectation maximization may not apply in the context of outcomes laden with affective responses, and that understanding the brain mechanisms of decision making requires the domain of the decision to be taken into account. PMID:25830918

The neural basis of risky choice with affective outcomes.

PubMed

Suter, Renata S; Pachur, Thorsten; Hertwig, Ralph; Endestad, Tor; Biele, Guido

2015-01-01

Both normative and many descriptive theories of decision making under risk are based on the notion that outcomes are weighted by their probability, with subsequent maximization of the (subjective) expected outcome. Numerous investigations from psychology, economics, and neuroscience have produced evidence consistent with this notion. However, this research has typically investigated choices involving relatively affect-poor, monetary outcomes. We compared choice in relatively affect-poor, monetary lottery problems with choice in relatively affect-rich medical decision problems. Computational modeling of behavioral data and model-based neuroimaging analyses provide converging evidence for substantial differences in the respective decision mechanisms. Relative to affect-poor choices, affect-rich choices yielded a more strongly curved probability weighting function of cumulative prospect theory, thus signaling that the psychological impact of probabilities is strongly diminished for affect-rich outcomes. Examining task-dependent brain activation, we identified a region-by-condition interaction indicating qualitative differences of activation between affect-rich and affect-poor choices. Moreover, brain activation in regions that were more active during affect-poor choices (e.g., the supramarginal gyrus) correlated with individual trial-by-trial decision weights, indicating that these regions reflect processing of probabilities. Formal reverse inference Neurosynth meta-analyses suggested that whereas affect-poor choices seem to be based on brain mechanisms for calculative processes, affect-rich choices are driven by the representation of outcomes' emotional value and autobiographical memories associated with them. These results provide evidence that the traditional notion of expectation maximization may not apply in the context of outcomes laden with affective responses, and that understanding the brain mechanisms of decision making requires the domain of the decision to be taken into account.

An investigation of the effect of instruction in physics on the formation of mental models for problem-solving in the context of simple electric circuits

NASA Astrophysics Data System (ADS)

Beh, Kian Lim

2000-10-01

This study was designed to explore the effect of a typical traditional method of instruction in physics on the formation of useful mental models among college students for problem-solving using simple electric circuits as a context. The study was also aimed at providing a comprehensive description of the understanding regarding electric circuits among novices and experts. In order to achieve these objectives, the following two research approaches were employed: (1) A students survey to collect data from 268 physics students; and (2) An interview protocol to collect data from 23 physics students and 24 experts (including 10 electrical engineering graduates, 4 practicing electrical engineers, 2 secondary school physics teachers, 8 physics lecturers, and 4 electrical engineers). Among the major findings are: (1) Most students do not possess accurate models of simple electric circuits as presented implicitly in physics textbooks; (2) Most students display good procedural understanding for solving simple problems concerning electric circuits but have no in-depth conceptual understanding in terms of practical knowledge of current, voltage, resistance, and circuit connections; (3) Most students encounter difficulty in discerning parallel connections that are drawn in a non-conventional format; (4) After a year of college physics, students show significant improvement in areas, including practical knowledge of current and voltage, ability to compute effective resistance and capacitance, ability to identify circuit connections, and ability to solve problems; however, no significance was found in practical knowledge of resistance and ability to connect circuits; and (5) The differences and similarities between the physics students and the experts include: (a) Novices perceive parallel circuits more in terms of 'branch', 'current', and 'resistors with the same resistance' while experts perceive parallel circuits more in terms of 'node', 'voltage', and 'less resistance'; and (b) Both novices and experts use phrases such as 'side-by side' and 'one on top of the other' in describing parallel circuits which emphasize the geometry of the standard circuit drawing when describing parallel resistors.

Chance, necessity and the origins of life: a physical sciences perspective

NASA Astrophysics Data System (ADS)

Hazen, Robert M.

2017-11-01

Earth's 4.5-billion-year history has witnessed a complex sequence of high-probability chemical and physical processes, as well as `frozen accidents'. Most models of life's origins similarly invoke a sequence of chemical reactions and molecular self-assemblies in which both necessity and chance play important roles. Recent research adds two important insights into this discussion. First, in the context of chemical reactions, chance versus necessity is an inherently false dichotomy-a range of probabilities exists for many natural events. Second, given the combinatorial richness of early Earth's chemical and physical environments, events in molecular evolution that are unlikely at limited laboratory scales of space and time may, nevertheless, be inevitable on an Earth-like planet at time scales of a billion years. This article is part of the themed issue 'Reconceptualizing the origins of life'.

``Physics with a Smile''-Explaining Phenomena with a Qualitative Problem-Solving Strategy

NASA Astrophysics Data System (ADS)

Mualem, Roni; Eylon, Bat-Sheva

2007-03-01

Various studies indicate that high school physics students and even college students majoring in physics have difficulties in qualitative understanding of basic concepts and principles of physics.1-5 For example, studies carried out with the Force Concept Inventory (FCI)1,6 illustrate that qualitative tasks are not easy to solve even at the college level. Consequently, "conceptual physics" courses have been designed to foster qualitative understanding, and advanced high school physics courses as well as introductory college-level courses strive to develop qualitative understanding. Many physics education researchers emphasize the importance of acquiring some qualitative understanding of basic concepts in physics as early as middle school or in the context of courses that offer "Physics First" in the ninth grade before biology or chemistry.7 This trend is consistent with the call to focus the science curriculum on a small number of basic concepts and ideas, and to instruct students in a more "meaningful way" leading to better understanding. Studies7-10 suggest that familiar everyday contexts (see Fig. 1) are useful in fostering qualitative understanding.

Evaluating changes in stream fish species richness over a 50-year time-period within a landscape context

USGS Publications Warehouse

Midway, Stephen R.; Wagner, Tyler; Tracy, Bryn H.; Hogue, Gabriela M.; Starnes, Wayne C.

2015-01-01

Worldwide, streams and rivers are facing a suite of pressures that alter water quality and degrade physical habitat, both of which can lead to changes in the composition and richness of fish populations. These potential changes are of particular importance in the Southeast USA, home to one of the richest stream fish assemblages in North America. Using data from 83 stream sites in North Carolina sampled in the 1960’s and the past decade, we used hierarchical Bayesian models to evaluate relationships between species richness and catchment land use and land cover (e.g., agriculture and forest cover). In addition, we examined how the rate of change in species richness over 50 years was related to catchment land use and land cover. We found a negative and positive correlation between forest land cover and agricultural land use and average species richness, respectively. After controlling for introduced species, most (66 %) stream sites showed an increase in native fish species richness, and the magnitude of the rate of increase was positively correlated to the amount of forested land cover in the catchment. Site-specific trends in species richness were not positive, on average, until the percentage forest cover in the network catchment exceeded about 55 %. These results suggest that streams with catchments that have moderate to high (>55 %) levels of forested land in upstream network catchments may be better able to increase the number of native species at a faster rate compared to less-forested catchments.

Patterns of behavior in online homework for introductory physics

NASA Astrophysics Data System (ADS)

Fredericks, Colin

Student activity in online homework was obtained from courses in physics in 2003 and 2005. This data was analyzed through a variety of methods, including principal component analysis, Pearson's r correlation, and comparison to performance measures such as detailed exam scores. Through this analysis it was determined which measured homework behaviors were associated with high exam scores and course grades. It was also determined that homework problems requiring analysis can have an impact on certain types of exam problems where traditional homework does not. Suggestions are given for future research and possible use of these methods in other contexts.

Using an innovative multiple regression procedure in a cancer population (Part II): fever, depressive affect, and mobility problems clarify an influential symptom pair (pain-fatigue/weakness) and cluster (pain-fatigue/weakness-sleep problems).

PubMed

Francoeur, Richard B

2015-01-01

Most patients with advanced cancer experience symptom pairs or clusters among pain, fatigue, and insomnia. However, only combinations where symptoms are mutually influential hold potential for identifying patient subgroups at greater risk, and in some contexts, interventions with "cross-over" (multisymptom) effects. Improved methods to detect and interpret interactions among symptoms, signs, or biomarkers are needed to reveal these influential pairs and clusters. I recently created sequential residual centering (SRC) to reduce multicollinearity in moderated regression, which enhances sensitivity to detect these interactions. I applied SRC to moderated regressions of single-item symptoms that interact to predict outcomes from 268 palliative radiation outpatients. I investigated: 1) the hypothesis that the interaction, pain × fatigue/weakness × sleep problems, predicts depressive affect only when fever presents, and 2) an exploratory analysis, when fever is absent, that the interaction, pain × fatigue/weakness × sleep problems × depressive affect, predicts mobility problems. In the fever context, three-way interactions (and derivative terms) of the four symptoms (pain, fatigue/weakness, fever, sleep problems) are tested individually and simultaneously; in the non-fever context, a single four-way interaction (and derivative terms) is tested. Fever interacts separately with fatigue/weakness and sleep problems; these comoderators each magnify the pain-depressive affect relationship along the upper or full range of pain values. In non-fever contexts, fatigue/weakness, sleep problems, and depressive affect comagnify the relationship between pain and mobility problems. Different mechanisms contribute to the pain × fatigue/weakness × sleep problems interaction, but all depend on the presence of fever, a sign/biomarker/symptom of proinflammatory sickness behavior. In non-fever contexts, depressive affect is no longer an outcome representing malaise from the physical symptoms of sickness, but becomes a fourth symptom of the interaction. In outpatient subgroups at heightened risk, single interventions could potentially relieve multiple symptoms when fever accompanies sickness malaise and in non-fever contexts with mobility problems. SRC strengthens insights into symptom pairs/clusters.

The Differential Impacts of Early Physical and Sexual Abuse and Internalizing Problems on Daytime Cortisol Rhythm in School-Aged Children

ERIC Educational Resources Information Center

Cicchetti, Dante; Rogosch, Fred A.; Gunnar, Megan R.; Toth, Sheree L.

2010-01-01

The impact of early physical and sexual abuse (EPA/SA) occurring in the first 5 years of life was investigated in relation to depressive and internalizing symptomatology and diurnal cortisol regulation. In a summer camp context, school-aged maltreated (n = 265) and nonmaltreated (n = 288) children provided morning and late afternoon saliva samples…

Video analysis for insight and coding: Examples from tutorials in introductory physics

NASA Astrophysics Data System (ADS)

Scherr, Rachel E.

2009-12-01

The increasing ease of video recording offers new opportunities to create richly detailed records of classroom activities. These recordings, in turn, call for research methodologies that balance generalizability with interpretive validity. This paper shares methodology for two practices of video analysis: (1) gaining insight into specific brief classroom episodes and (2) developing and applying a systematic observational protocol for a relatively large corpus of video data. These two aspects of analytic practice are illustrated in the context of a particular research interest but are intended to serve as general suggestions.

β-decay studies of r-process nuclei at NSCL

NASA Astrophysics Data System (ADS)

Pereira, J.; Aprahamian, A.; Arndt, O.; Becerril, A.; Elliot, T.; Estrade, A.; Galaviz, D.; Hennrich, S.; Hosmer, P.; Schnorrenberger, L.; Kessler, R.; Kratz, K.-L.; Lorusso, G.; Mantica, P. F.; Matos, M.; Montes, F.; Pfeiffer, B.; Quinn, M.; Santi, P.; Schatz, H.; Schertz, F.; Smith, E.; Tomlin, B. E.; Walters, W. B.; Wöhr, A.

2008-06-01

Observed neutron-capture elemental abundances in metal-poor stars, along with ongoing analysis of the extremely metal-poor Eu-enriched sub-class provide new guidance for astrophysical models aimed at finding the r-process sites. The present paper emphasizes the importance of nuclear physics parameters entering in these models, particularly β-decay properties of neutron-rich nuclei. In this context, several r-process motivated β-decay experiments performed at the National Superconducting Cyclotron Laboratory (NSCL) are presented, including a summary of results and impact on model calculations.

Nature of the Physical Observer

NASA Astrophysics Data System (ADS)

Osoroma, Drahcir S.

2010-12-01

The nature of the observer has long plagued physical science. Here we review the current status of cognitive science in the context of a cosmology of mind in an Anthropic Multiverse. The concept of an élan vital or life force has long been considered the elementary action principle driving the evolution of living-systems by theologically minded scientists and individuals. Sufficiently extending Einstein's original model of a Static Universe, to a Holographic Anthropic Multiverse (HAM), provides a context for solving this centuries old problem for introducing this type of teleological principle into Physics, Biology, Medicine and Psychology. This means the contemporary framework of biological mechanism should no longer be considered the formal philosophical basis for describing living systems and contemporary allopathic (scientific) medicine. The new noetic action principle has far reaching implications for medicine and transpersonal psychology.

Secondary implementation of interactive engagement teaching techniques: Choices and challenges in a Gulf Arab context

NASA Astrophysics Data System (ADS)

Hitt, G. W.; Isakovic, A. F.; Fawwaz, O.; Bawa'aneh, M. S.; El-Kork, N.; Makkiyil, S.; Qattan, I. A.

2014-12-01

We report on efforts to design the "Collaborative Workshop Physics" (CWP) instructional strategy to deliver the first interactive engagement (IE) physics course at Khalifa University of Science, Technology and Research (KU), United Arab Emirates (UAE). To our knowledge, this work reports the first calculus-based, introductory mechanics course on the Arabian Peninsula using physics education research (PER)-based instruction. A brief history and present context of general university and STEM teaching in the UAE is given. We present this secondary implementation (SI) as a case study of a novel context and use it to determine if PER-based instruction can be successfully implemented far from the cultural context of the primary developer and, if so, how might such SIs differ from SIs within the United States (U.S.) in terms of criteria for and risks to their success. With these questions in view, a prereform baseline comprised of Maryland Physics Expectations in Physics survey, Force Concept Inventory (FCI), course exam grades, and English language proficiency data are used to design a hybrid implementation of Cooperative Group Problem Solving. We find that for students with high English proficiency, normalized gain on FCI improves substantially, from ⟨g⟩=0.16±0.10 prereform to ⟨g⟩=0.47±0.08 in the CWP pilot (standard errors), indicating a successful SI. However, we also find evidence that normalized gains on FCI are strongly modulated by language proficiency and discuss likely causes. Regardless of language ability, problem-solving skill is also substantially improved and course drop-fail-withdrawal rates are cut from 50% to 24%. In particular, we find evidence in postreform student interviews that prior classroom experiences, and not broader cultural expectations about education, are the more significant cause of expectations that are at odds with the classroom norms of well-functioning PER-based instruction. We present this result as evidence that PER-based innovations can be implemented across great changes in cultural context, provided that the method is thoughtfully adapted in anticipation of context and culture-specific student expectations. This case study should be valuable for future reforms at KU, the broader Gulf region, and other institutions facing similar challenges involving SI of PER-based instruction outside the U.S.

Canonical Descriptions of High Intensity Laser-Plasma Interaction

NASA Astrophysics Data System (ADS)

Le Cornu, B. J.

The problem of laser-plasma interaction has been studied extensively in the context of inertial confinement fusion (ICF). These studies have focussed on effects like the nonlinear force, self-focusing, Rayleigh- Taylor instabilities, stimulated Brillouin scattering and stimulated Raman scattering observed in ICF schemes. However, there remains a large discrepancy between theory and experiment in the context of nuclear fusion schemes. Several authors have attempted to gain greater understanding of the physics involved by the application of standard or 'canonical' methods used in Lagrangian and Hamiltonian mechanics to the problem of plasma physics. This thesis presents a new canonical description of laser-plasma interaction based on the Podolsky Lagrangian. Finite self-energy of charged particles, incroporation of high-frequency effects and an ability to quantise are the main advantages of this new model. The nature of the Podolsky constant is also analysed in the context of plasma physics, specifically in terms of the plasma dispersion relation. A new gauge invariant expression of the energy-momentum tensor for any gauge invariant Lagrangian dependent on second order derivatives is derived for the first time. Finally, the transient and nontransient expressions of the nonlinear ponderomotive force in laser-plasma interaction are discussed and shown to be closely approximated by a canonical derivation of the electromagnetic Lagrangian, a fact that seems to have been missed in the literature.

A study of meteor spectroscopy and physics from earth-orbit: A preliminary survey into ultraviolet meteor spectra

NASA Technical Reports Server (NTRS)

Meisel, D. D.

1976-01-01

Preliminary data required to extrapolate available meteor physics information (obtained in the photographic, visual and near ultraviolet spectral regions) into the middle and far ultraviolet are presented. Wavelength tables, telluric attenuation factors, meteor rates, and telluric airglow data are summarized in the context of near-earth observation vehicle parameters using moderate to low spectral resolution instrumentation. Considerable attenuation is given to the problem of meteor excitation temperatures since these are required to predict the strength of UV features. Relative line intensities are computed for an assumed chondritic composition. Features of greatest predicted intensities, the major problems in meteor physics, detectability of UV meteor events, complications of spacecraft motion, and UV instrumentation options are summarized.

The Gibbs paradox and the physical criteria for indistinguishability of identical particles

NASA Astrophysics Data System (ADS)

Unnikrishnan, C. S.

2016-08-01

Gibbs paradox in the context of statistical mechanics addresses the issue of additivity of entropy of mixing gases. The usual discussion attributes the paradoxical situation to classical distinguishability of identical particles and credits quantum theory for enabling indistinguishability of identical particles to solve the problem. We argue that indistinguishability of identical particles is already a feature in classical mechanics and this is clearly brought out when the problem is treated in the language of information and associated entropy. We pinpoint the physical criteria for indistinguishability that is crucial for the treatment of the Gibbs’ problem and the consistency of its solution with conventional thermodynamics. Quantum mechanics provides a quantitative criterion, not possible in the classical picture, for the degree of indistinguishability in terms of visibility of quantum interference, or overlap of the states as pointed out by von Neumann, thereby endowing the entropy expression with mathematical continuity and physical reasonableness.

Additional Crime Scenes for Projectile Motion Unit

NASA Astrophysics Data System (ADS)

Fullerton, Dan; Bonner, David

2011-12-01

Building students' ability to transfer physics fundamentals to real-world applications establishes a deeper understanding of underlying concepts while enhancing student interest. Forensic science offers a great opportunity for students to apply physics to highly engaging, real-world contexts. Integrating these opportunities into inquiry-based problem solving in a team environment provides a terrific backdrop for fostering communication, analysis, and critical thinking skills. One such activity, inspired jointly by the museum exhibit "CSI: The Experience"2 and David Bonner's TPT article "Increasing Student Engagement and Enthusiasm: A Projectile Motion Crime Scene,"3 provides students with three different crime scenes, each requiring an analysis of projectile motion. In this lesson students socially engage in higher-order analysis of two-dimensional projectile motion problems by collecting information from 3-D scale models and collaborating with one another on its interpretation, in addition to diagramming and mathematical analysis typical to problem solving in physics.

Neutron matter with Quantum Monte Carlo: chiral 3N forces and static response

DOE PAGES

Buraczynski, M.; Gandolfi, S.; Gezerlis, A.; ...

2016-03-14

Neutron matter is related to the physics of neutron stars and that of neutron-rich nuclei. Moreover, Quantum Monte Carlo (QMC) methods offer a unique way of solving the many-body problem non-perturbatively, providing feedback on features of nuclear interactions and addressing scenarios that are inaccessible to other approaches. Our contribution goes over two recent accomplishments in the theory of neutron matter: a) the fusing of QMC with chiral effective field theory interactions, focusing on local chiral 3N forces, and b) the first attempt to find an ab initio solution to the problem of static response.

Explaining suicide in an urban slum of Mumbai, India: a sociocultural autopsy.

PubMed

Parkar, Shubhangi R; Nagarsekar, Balkrishna; Weiss, Mitchell G

2009-01-01

Health demographic mortality studies use verbal autopsies to identify suicide as a cause of death. Psychological autopsies focus almost exclusively on associated high-risk psychiatric disorders. New approaches considering contextual factors are needed for preventing suicide and promoting mental health. This study examined explanations of suicide reported by surviving family members or close friends with reference to social, cultural, and environmental conditions as well as the challenges of life in the Malavani slum of Mumbai. An EMIC (Explanatory Model Interview Catalog) interview based on a cultural epidemiological framework considered underlying problems, perceived causes, and sociocultural contexts. It was administered to survivors of 76 people who had died by suicide (56.6% women). Accounts of underlying problems typically referred to various aspects of tension (73.7%). Perceived causes often identified multiple factors. The sociocultural contexts of suicide included the victimization of women, the personal and social impact of problem drinking, marital problems, physical health problems, mental tension, possession and sorcery. Women were particularly vulnerable to the impact of problem drinking by a spouse or father. This study demonstrates the value of an approach to sociocultural autopsy examining local contexts and explanations of suicide. Findings highlight needs for both mental health services and culturally sensitive social interventions.

Parental physical illness as a risk for psychosocial maladjustment in children and adolescents: epidemiological findings from a national survey in Germany.

PubMed

Barkmann, Claus; Romer, Georg; Watson, Maggie; Schulte-Markwort, Michael

2007-01-01

The authors assessed the risk for psychosocial maladjustment in a population-based sample of dependent children of parents with serious physical illness. In the context of The Hamburg Health Survey, a wide range of data on current life situation and health status was collected from a representative sample of families with children and adolescents between 4 and 18 years old (N=1,950). For 4- to 18-year-old children and adolescents in Germany, the prevalence of a serious physical illness in a parent was 4.1%. The adjusted risk of psychosocial maladjustment in this target group, depending on the case definition, is elevated, with internalizing problems being more prevalent than externalizing problems. Although problems for affected boys decline with puberty, they increase for girls. In this age-group, girls and boys appear to be under particular strain when the respective same-sex parent has a serious physical illness. Exposure to serious parental physical illness is an epidemiologically relevant risk factor for psychosocial maladjustment in children and adolescents that needs to be better recognized by medical professionals.

Safety of sports facilities and training of graduates in physical education.

PubMed

Romano Spica, V; Giampaoli, S; Di Onofrio, V; Liguori, G

2015-01-01

Post-industrial societies have to face the problem of physical inactivity and inappropriate lifestyles. Programs to promote physical activity are strongly supported by supranational, national and local institutions and organizations. These programs can be developed in sport facilities but also in places that are not institutionally dedicated to sport. The use of urban and working sites has the advantage of better reach the various segments of the population, but at the same time requires coordination between various professionals in structuring an effective intervention. Bibliographical research in the historical archives of the library of the University of Rome Foro Italico, online databases, paleoigiene (wikigiene), documents archives (GSMS-SItI, WHO, ISS, OsEPi, INAIL, ISTAT, national laws). Several guidelines and regulations face the problem of safety in sport environments. The context is in rapid evolution and directions are provided by public health authorities. Graduates in Sport and Physical Activity, represent an additional resource in terms of: prevention and safety in the workplace, health education, application of preventive and adapted physical activities in the territory. These tasks can be integrated in all prevention stages: e.g. childhood and primary prevention programs in school, adapted physical activity for the elderly. The contribution of public health specialists is strategic in the surveillance and coordination of integrated projects. At the same time, graduates in Physical Education appear to be pivots for health promotion and qualified resources for institutions in the territory. Their training should always include contents related to prevention and safety, regulations on sport and working environments, along with bases of preventive medicine related to the context of physical activity.

Studying primate learning in group contexts: Tests of social foraging, response to novelty, and cooperative problem solving.

PubMed

Drea, Christine M

2006-03-01

Learning commonly refers to the modification of behavior through experience, whereby an animal gains information about stimulus-response contingencies from interacting with its physical environment. Social learning, on the other hand, occurs when the same information originates, not from the animal's personal experience, but from the actions of others. Socially biased learning is the 'collective outcome of interacting physical, social, and individual factors' [D. Fragaszy, E. Visalberghi, Learn. Behav. 32 (2004) 24-35.] (see p. 24). Mounting interest in animal social learning has brought with it certain innovations in animal testing procedures. Variants of the observer-demonstrator and cooperation paradigms, for instance, have been used widely in captive settings to examine the transmission or coordination of behavior, respectively, between two animals. Relatively few studies, however, have examined social learning in more complex group settings and even fewer have manipulated the social environment to empirically test the effect of group dynamics on problem solving. The present paper outlines procedures for group testing captive non-human primates, in spacious arenas, to evaluate the social modulation of learning and performance. These methods are illustrated in the context of (1) naturalistic social foraging problems, modeled after traditional visual discrimination paradigms, (2) response to novel objects and novel extractive foraging tasks, and (3) cooperative problem solving. Each example showcases the benefits of experimentally manipulating social context to compare an animal's performance in intact groups (or even pairs) against its performance under different social circumstances. Broader application of group testing procedures and manipulation of group composition promise to provide meaningful insight into socially biased learning.

Chance, necessity and the origins of life: a physical sciences perspective.

PubMed

Hazen, Robert M

2017-12-28

Earth's 4.5-billion-year history has witnessed a complex sequence of high-probability chemical and physical processes, as well as 'frozen accidents'. Most models of life's origins similarly invoke a sequence of chemical reactions and molecular self-assemblies in which both necessity and chance play important roles. Recent research adds two important insights into this discussion. First, in the context of chemical reactions, chance versus necessity is an inherently false dichotomy-a range of probabilities exists for many natural events. Second, given the combinatorial richness of early Earth's chemical and physical environments, events in molecular evolution that are unlikely at limited laboratory scales of space and time may, nevertheless, be inevitable on an Earth-like planet at time scales of a billion years.This article is part of the themed issue 'Reconceptualizing the origins of life'. © 2017 The Author(s).

Traditional Practicing with Arsenic Rich Water in Fish Industries Leads to Health Hazards in West Bengal and North-Eastern States of India

NASA Astrophysics Data System (ADS)

Kashyap, C. A.

2014-12-01

The supply of good quality food is main necessity for economic and social health of urban and rural population throughout the globe. This study comes to know the severity of As in the west Bengal and north-eastern states of the India. Over the 75% large population of India lives in villages and associated with farming and its related work. West Bengal is the densest populated area of India, fish and rice is the staple food as well as in north-eastern states. For the fulfil demand of fish large population the area are used fisheries as the business. Arsenic contamination in ground water is major growing threat to worldwide drinking water resources. High As contamination in water have been reported in many parts of the world Chandrasekharam et al., 2001; Smedley and Kinniburgh, 2002; Farooq et al., 2010). In context to West Bengal and north-east states of India arsenic is main problem in the food chain. These areas are very rich in arsenic many fold higher concentrations of Arsenic than their respective WHO permissible limits have been reported in the water. Over the 36 million people in Bengal delta are at risk due to drinking of As contaminated water (Nordstrom, 2002). The highest concentration of arsenic (535 μg/L Chandrashekhar et al. 2012) was registered from Ngangkha Lawai Mamang Leikai area of Bishnupur district which is fifty fold of the WHO limit for arsenic and tenfold of Indian permissible limit. With the continuous traditional practicing (As rich water pond) and untreated arsenic rich water in fish industries leads to health hazards. A sustainable development in aquaculture should comprise of various fields including environmental, social, cultural and economic aspects. A scientific study has to be needed for the overcome on this problem and rain harvested water may be used for reduce the arsenic problems in fisheries.

Replicating effective pedagogical approaches from introductory physics to improve student learning of quantum mechanics

NASA Astrophysics Data System (ADS)

Sayer, Ryan Thomas

Upper-level undergraduate students entering a quantum mechanics (QM) course are in many ways similar to students entering an introductory physics course. Numerous studies have investigated the difficulties that novices face in introductory physics as well as the pedagogical approaches that are effective in helping them overcome those difficulties. My research focuses on replicating effective approaches and instructional strategies used in introductory physics courses to help advanced students in an upper-level QM course. I have investigated the use of Just-in-time Teaching (JiTT) and peer discussion involving clicker questions in an upper-level quantum mechanics course. The JiTT approach including peer discussions was effective in helping students overcome their difficulties and improve their understanding of QM concepts. Learning tools, such as a Quantum Interactive Learning Tutorial (QuILT) based on the Doubleslit Experiment (DSE) which I helped develop, have been successful in helping upper-level undergraduate students improve their understanding of QM. Many students have also demonstrated the ability to transfer knowledge from a QuILT based on the Mach-Zehnder interferometer while working on the DSE QuILT. In addition, I have been involved in implementing research-based activities during our semester-long professional development course for teaching assistants (TAs). In one intervention, TAs were asked to grade student solutions to introductory physics problems first using their choice of method, then again using a rubric designed to promote effective problem-solving approaches, then once more at the end of the semester using their choice of method. This intervention found that many TAs have ingrained beliefs about the purposes of grading which include placing the burden of proof on the instructor as well as a belief that grading cannot serve as a formative assessment. I also compared TAs grading practices and considerations when grading student solutions to QM problems versus when grading student solutions to introductory physics. Many TAs penalized students for not explicating the problem solving process more often in the QM context than in the introductory physics context. The implications of these interventions for promoting student learning in QM are discussed.

Environmental Accounting for the Urban Water System: Past, Present and Future - Oregon

EPA Science Inventory

The modern urban water system (UWS), or the provision of supply, sanitation and drainage services in an urban context, represents the ever-evolving physical manifestation of society’s propensity to solve pressing water problems. While solutions generally entail immediate be...

Contextual Influences on Resistance to Disruption in Children with Intellectual Disabilities

ERIC Educational Resources Information Center

Lionello-DeNolf, Karen; Dube, William V.

2011-01-01

Training context can influence resistance to disruption under differing reinforcement schedules. With nonhumans, when relatively lean and rich reinforcement schedules are experienced in the context of a multiple schedule, greater resistance is found in the rich than the lean component, as described by behavioral momentum theory. By contrast, when…

Research on a Unique Instructional Framework for Elevating Students’ Quantitative Problem Solving Abilities

NASA Astrophysics Data System (ADS)

Prather, Edward E.; Wallace, Colin Scott

2018-06-01

We present an instructional framework that allowed a first time physics instructor to improve students quantitative problem solving abilities by more than a letter grade over what was achieved by students in an experienced instructor’s course. This instructional framework uses a Think-Pair-Share approach to foster collaborative quantitative problem solving during the lecture portion of a large enrollment introductory calculus-based mechanics course. Through the development of carefully crafted and sequenced TPS questions, we engage students in rich discussions on key problem solving issues that we typically only hear about when a student comes for help during office hours. Current work in the sophomore E&M course illustrates that this framework is generalizable to classes beyond the introductory level and for topics beyond mechanics.

Microporoelastic Modeling of Organic-Rich Shales

NASA Astrophysics Data System (ADS)

Khosh Sokhan Monfared, S.; Abedi, S.; Ulm, F. J.

2014-12-01

Organic-rich shale is an extremely complex, naturally occurring geo-composite. The heterogeneous nature of organic-rich shale and its anisotropic behavior pose grand challenges for characterization, modeling and engineering design The intricacy of organic-rich shale, in the context of its mechanical and poromechanical properties, originates in the presence of organic/inorganic constituents and their interfaces as well as the occurrence of porosity and elastic anisotropy, at multiple length scales. To capture the contributing mechanisms, of 1st order, responsible for organic-rich shale complex behavior, we introduce an original approach for micromechanical modeling of organic-rich shales which accounts for the effect of maturity of organics on the overall elasticity through morphology considerations. This morphology contribution is captured by means of an effective media theory that bridges the gap between immature and mature systems through the choice of system's microtexture; namely a matrix-inclusion morphology (Mori-Tanaka) for immature systems and a polycrystal/granular morphology for mature systems. Also, we show that interfaces play a role on the effective elasticity of mature, organic-rich shales. The models are calibrated by means of ultrasonic pulse velocity measurements of elastic properties and validated by means of nanoindentation results. Sensitivity analyses using Spearman's Partial Rank Correlation Coefficient shows the importance of porosity and Total Organic Carbon (TOC) as key input parameters for accurate model predictions. These modeling developments pave the way to reach a "unique" set of clay properties and highlight the importance of depositional environment, burial and diagenetic processes on overall mechanical and poromechanical behavior of organic-rich shale. These developments also emphasize the importance of understanding and modeling clay elasticity and organic maturity on the overall rock behavior which is of critical importance for a practical rock physics model that accounts for time dependent phenomena which can be employed for seismic inversion.

Entering the policy debate: An economic evaluation of groundwater policy in flux

NASA Astrophysics Data System (ADS)

Livingston, Marie Leigh; Garrido, Alberto

2004-12-01

This is an age of transition in groundwater policy. The ownership and control of aquifers, changing groundwater quality, and the impact of groundwater on the environment command the attention of policy makers around the globe. Substantial pressure exists for change in the laws and regulations governing groundwater, which are critical to the management of this critical resource. The objective of this paper is to contribute to the practical policy debate from an economic perspective. This study begins by outlining the basic stages of change in groundwater policy and their economic relevance. A set of physical, economic, and institutional indicators are suggested that may help to understand various country issues. The indicators are used to describe some actual experiences in groundwater policy in the United States and Spain that are examined for insights into common policy questions. This study suggests that the public authority to initiate groundwater policy innovations often results from the physical ties between surface and groundwater. In contexts rich with spatial and temporal externalities the situation is more complex, but this increases the social benefits that result from successful reform. A credible threat of losing rights is often necessary to create enough incentives to firm existing rights. Reductions in overall use are better achieved through purchasing and retiring rights, rather than through compensation for nonuse. Finally, the policy issues important to groundwater are often more fundamental than pricing alone. These insights may help policy makers adapt to emerging groundwater management problems.

They go straight home - don't they? Using global positioning systems to assess adolescent school-travel patterns.

PubMed

Voss, Christine; Winters, Meghan; Frazer, Amanda D; McKay, Heather A

2014-12-01

Active travel to school is a potential source of physical activity for adolescents, but its assessments often rely on assumptions around travel patterns. Global positioning system (GPS) and accelerometry provide an objective assessment of physical activity from school-travel and the context in which it occurs (where, when, how long). To describe school-travel patterns of adolescents and to compare estimates of physical activity during the hour before/after school - a commonly used proxy for school-travel time - with physical activity accrued during school trips identified through GPS ('GPS-trips'). Adolescents ( n =49, 13.3±0.7 years, 37% female) from Downtown Vancouver wore an accelerometer (GT3X+) and GPS (Qstarz) for 7 days (October 2012). Minutes of moderate-to-vigorous physical activity (MVPA) during the hour before/after school and during GPS-trips were calculated for the n =130 school-trips made by 43 students. We used multilevel linear regression to assess the association between MVPA during GPS-trips and MVPA during the hour/before school. Only 55% of school-trips were from/to home and within the hour before/after school ('normal'). Estimates of MVPA during the hour before/after school were higher than during GPS-trips (12.0 vs. 8.0 min). On average, MVPA during GPS-trips was linearly associated with MVPA during the hour before/after school, suggesting that physical activity levels during the hour before/after school are broadly reflective of physical activity from school-travel. GPS and accelerometry provide context-rich information relating to school-travel. The hour before/after school may - on average - provide a simple means to crudely estimate physical activity from school-travel when GPS are not available.

They go straight home – don’t they? Using global positioning systems to assess adolescent school-travel patterns

PubMed Central

Voss, Christine; Winters, Meghan; Frazer, Amanda D.; McKay, Heather A.

2015-01-01

Background Active travel to school is a potential source of physical activity for adolescents, but its assessments often rely on assumptions around travel patterns. Global positioning system (GPS) and accelerometry provide an objective assessment of physical activity from school-travel and the context in which it occurs (where, when, how long). Purpose To describe school-travel patterns of adolescents and to compare estimates of physical activity during the hour before/after school – a commonly used proxy for school-travel time – with physical activity accrued during school trips identified through GPS (‘GPS-trips’). Methods Adolescents (n=49, 13.3±0.7 years, 37% female) from Downtown Vancouver wore an accelerometer (GT3X+) and GPS (Qstarz) for 7 days (October 2012). Minutes of moderate-to-vigorous physical activity (MVPA) during the hour before/after school and during GPS-trips were calculated for the n=130 school-trips made by 43 students. We used multilevel linear regression to assess the association between MVPA during GPS-trips and MVPA during the hour/before school. Results Only 55% of school-trips were from/to home and within the hour before/after school (‘normal’). Estimates of MVPA during the hour before/after school were higher than during GPS-trips (12.0 vs. 8.0 min). On average, MVPA during GPS-trips was linearly associated with MVPA during the hour before/after school, suggesting that physical activity levels during the hour before/after school are broadly reflective of physical activity from school-travel. Conclusion GPS and accelerometry provide context-rich information relating to school-travel. The hour before/after school may – on average – provide a simple means to crudely estimate physical activity from school-travel when GPS are not available. PMID:26793437

Teaching medical physics to general audiences.

PubMed Central

Amador, S

1994-01-01

By judiciously selecting topics and reading materials, one can teach a full semester course on medical physics appropriate for college students not majoring in the natural sciences. This interdisciplinary field offers an opportunity to teach a great deal of basic physics at the freshman level in the context of explaining modern medical technologies such as ultrasound imaging, laser surgery, and positron emission tomography. This article describes one such course which combines lectures, outside visitors, varied readings, and laboratories to convey a select subset of physical principles and quantitative problem-solving skills. These resources are also valuable for enriching the standard freshman physics sequence for premedical students. PMID:8075355

Aid in the midst of plenty: oil wealth, misery and advocacy in Angola.

PubMed

Le Billon, Philippe

2005-03-01

This paper examines advocacy initiatives by humanitarian and human rights organisations to address problems of governance in resource-rich and conflict-affected countries, focussing on the case of Angola. Humanitarian principles preclude the use of indiscriminate conditionality and point towards a cautious approach to advocacy aimed at assisting vulnerable populations. Furthermore, the relatively insignificant amount of aid supplied to resource-rich local authorities means that individual agencies have precious little leverage, especially when commercial interests rather than humanitarian or 'good governance' principles influence the priorities of bilateral donors. A context of resource wealth calls for: high levels of coordination and cooperation between human rights groups, aid agencies and donors; balanced use of conditionality, based on the drawing, by donors, of a clear distinction between emergency and development-oriented assistance; and a sustained effort to highlight the responsibilities of local authorities, foreign governments and businesses in meeting humanitarian and development objectives.

Physical properties of the WR stars in Westerlund 1

NASA Astrophysics Data System (ADS)

Rosslowe, C. K.; Crowther, P. A.; Clark, J. S.; Negueruela, I.

The Westerlund 1 (Wd1) cluster hosts a rich and varied collection of massive stars. Its dynamical youth and the absence of ongoing star formation indicate a coeval population. As such, the simultaneous presence of both late-type supergiants and Wolf-Rayet stars has defied explanation in the context of single-star evolution. Observational evidence points to a high binary fraction, hence this stellar population offers a robust test for stellar models accounting for both single-star and binary evolution. We present an optical to near-IR (VLT & NTT) spectroscopic analysis of 22 WR stars in Wd 1, delivering physical properties for the WR stars. We discuss how these differ from the Galactic field population, and how they may be reconciled with the predictions of single and binary evolutionary models.

Formation of quasiparallel Alfven solitons

NASA Technical Reports Server (NTRS)

Hamilton, R. L.; Kennel, C. F.; Mjolhus, E.

1992-01-01

The formation of quasi-parallel Alfven solitons is investigated through the inverse scattering transformation (IST) for the derivative nonlinear Schroedinger (DNLS) equation. The DNLS has a rich complement of soliton solutions consisting of a two-parameter soliton family and a one-parameter bright/dark soliton family. In this paper, the physical roles and origins of these soliton families are inferred through an analytic study of the scattering data generated by the IST for a set of initial profiles. The DNLS equation has as limiting forms the nonlinear Schroedinger (NLS), Korteweg-de-Vries (KdV) and modified Korteweg-de-Vries (MKdV) equations. Each of these limits is briefly reviewed in the physical context of quasi-parallel Alfven waves. The existence of these limiting forms serves as a natural framework for discussing the formation of Alfven solitons.

Strongly interacting dynamics and the search for new physics at the LHC

DOE PAGES

Appelquist, T.; Brower, R. C.; Fleming, G. T.; ...

2016-06-21

We present results for the spectrum of a strongly interacting SU(3) gauge theory with N f = 8 light fermions in the fundamental representation. Carrying out nonperturbative lattice calculations at the lightest masses and largest volumes considered to date, we confirm the existence of a remarkably light singlet scalar particle. We explore the rich resonance spectrum of the 8-flavor theory in the context of the search for new physics beyond the standard model at the Large Hadron Collider (LHC). Lastly, connecting our results to models of dynamical electroweak symmetry breaking, we estimate the vector resonance mass to be about 2more » TeV with a width of roughly 450 GeV, and predict additional resonances with masses below ~3 TeV.« less

Mechanochemical spinodal decomposition: a phenomenological theory of phase transformations in multi-component, crystalline solids

DOE PAGES

Rudraraju, Shiva; Van der Ven, Anton; Garikipati, Krishna

2016-06-10

Here, we present a phenomenological treatment of diffusion-driven martensitic phase transformations in multi-component crystalline solids that arise from non-convex free energies in mechanical and chemical variables. The treatment describes diffusional phase transformations that are accompanied by symmetry-breaking structural changes of the crystal unit cell and reveals the importance of a mechanochemical spinodal, defined as the region in strain-composition space, where the free-energy density function is non-convex. The approach is relevant to phase transformations wherein the structural order parameters can be expressed as linear combinations of strains relative to a high-symmetry reference crystal. The governing equations describing mechanochemical spinodal decomposition aremore » variationally derived from a free-energy density function that accounts for interfacial energy via gradients of the rapidly varying strain and composition fields. A robust computational framework for treating the coupled, higher-order diffusion and nonlinear strain gradient elasticity problems is presented. Because the local strains in an inhomogeneous, transforming microstructure can be finite, the elasticity problem must account for geometric nonlinearity. An evaluation of available experimental phase diagrams and first-principles free energies suggests that mechanochemical spinodal decomposition should occur in metal hydrides such as ZrH 2-2c. The rich physics that ensues is explored in several numerical examples in two and three dimensions, and the relevance of the mechanism is discussed in the context of important electrode materials for Li-ion batteries and high-temperature ceramics.« less

ContextProvider: Context awareness for medical monitoring applications.

PubMed

Mitchell, Michael; Meyers, Christopher; Wang, An-I Andy; Tyson, Gary

2011-01-01

Smartphones are sensor-rich and Internet-enabled. With their on-board sensors, web services, social media, and external biosensors, smartphones can provide contextual information about the device, user, and environment, thereby enabling the creation of rich, biologically driven applications. We introduce ContextProvider, a framework that offers a unified, query-able interface to contextual data on the device. Unlike other context-based frameworks, ContextProvider offers interactive user feedback, self-adaptive sensor polling, and minimal reliance on third-party infrastructure. ContextProvider also allows for rapid development of new context and bio-aware applications. Evaluation of ContextProvider shows the incorporation of an additional monitoring sensor into the framework with fewer than 100 lines of Java code. With adaptive sensor monitoring, power consumption per sensor can be reduced down to 1% overhead. Finally, through the use of context, accuracy of data interpretation can be improved by up to 80%.

The Free Energy in the Derrida-Retaux Recursive Model

NASA Astrophysics Data System (ADS)

Hu, Yueyun; Shi, Zhan

2018-05-01

We are interested in a simple max-type recursive model studied by Derrida and Retaux (J Stat Phys 156:268-290, 2014) in the context of a physics problem, and find a wide range for the exponent in the free energy in the nearly supercritical regime.

STEM education and Fermi problems

NASA Astrophysics Data System (ADS)

Holubova, Renata

2017-01-01

One of the research areas of Physics education is the study of the educational process. Investigations in this area are aimed for example on the teaching and learning process and its results. The conception of STEM education (Science, Technology, Engineering, and Mathematics) is discussed - it is one possible approach to the preparation of the curriculum and the focus on the educational process at basic and secondary schools. At schools in the Czech Republic STEM is much more realized by the application of interdisciplinary relations between subjects Physics-Nature-Technique. In both conceptions the aim is to support pupils' creativity, critical thinking, cross-curricular links. In this context the possibility of using Fermi problems in teaching Physics was discussed (as an interdisciplinary and constructivist activity). The aim of our research was the analysis of Fermi problems solving strategies, the ability of pupils to solve Fermi problems. The outcome of our analysis was to find out methods and teaching strategies which are important to use in teaching - how to solve qualitative and interdisciplinary tasks in physics. In this paper the theoretical basis of STEM education and Fermi problems will be presented. The outcome of our findings based on the research activities will be discussed so as our experiences from 10 years of Fermi problems competition that takes place at the Science Faculty, Palacky University in Olomouc. Changes in competencies of solving tasks by our students (from the point of view in terms of modern, activating teaching methods recommended by theory of Physics education and other science subjects) will be identified.

Crack problems involving nonhomogeneous interfacial regions in bonded materials

NASA Technical Reports Server (NTRS)

Erdogan, F.

1990-01-01

Consideration is given to two classes of fracture-related solid mechanics problems in which the model leads to some physically anomalous results. The first is the interface crack problem associated with the debonding process in which the corresponding elasticity solution predicts severe oscillations of stresses and the crack surface displacements vary near the crack tip. The second deals with crack intersecting the interface. The nature of the solutions around the crack tips arising from these problems is reviewed. The rationale for introducing a new interfacial zone model is discussed, its analytical consequences within the context of the two crack-problem classes are described, and some examples are presented.

Problem Solving in Physics: Undergraduates' Framing, Procedures, and Decision Making

NASA Astrophysics Data System (ADS)

Modir, Bahar

In this dissertation I will start with the broad research question of what does problem solving in upper division physics look like? My focus in this study is on students' problem solving in physics theory courses. Some mathematical formalisms are common across all physics core courses such as using the process of separation of variables, doing Taylor series, or using the orthogonality properties of mathematical functions to set terms equal to zero. However, there are slight differences in their use of these mathematical formalisms across different courses, possibly because of how students map different physical systems to these processes. Thus, my first main research question aims to answer how students perform these recurring processes across upper division physics courses. I break this broad question into three particular research questions: What knowledge pieces do students use to make connections between physics and procedural math? How do students use their knowledge pieces coherently to provide reasoning strategies in estimation problems? How do students look ahead into the problem to read the information out of the physical scenario to align their use of math in physics? Building on the previous body of the literature, I will use the theory family of Knowledge in Pieces and provide evidence to expand this theoretical foundation. I will compare my study with previous studies and provide suggestions on how to generalize these theory expansions for future use. My experimental data mostly come from video-based classroom data. Students in groups of 2-4 students solve in-class problems in quantum mechanics and electromagnetic fields 1 courses collaboratively. In addition, I will analyze clinical interviews to demonstrate how a single case study student plays an epistemic game to estimate the total energy in a hurricane. My second research question is more focused on a particular instructional context. How do students frame problem solving in quantum mechanics? I will lay out a new theoretical framework based in epistemic framing that separates the problem solving space into four frames divided along two axes. The first axis models students' framing in math and physics, expanded through the second axis of conceptual problem solving and algorithmic problem solving. I use this framework to show how students navigate problem solving. Lastly, I will use this developed framework to interpret existing difficulties in quantum mechanics.

An analysis of science content and representations in introductory college physics textbooks and multimodal learning resources

NASA Astrophysics Data System (ADS)

Donnelly, Suzanne M.

This study features a comparative descriptive analysis of the physics content and representations surrounding the first law of thermodynamics as presented in four widely used introductory college physics textbooks representing each of four physics textbook categories (calculus-based, algebra/trigonometry-based, conceptual, and technical/applied). Introducing and employing a newly developed theoretical framework, multimodal generative learning theory (MGLT), an analysis of the multimodal characteristics of textbook and multimedia representations of physics principles was conducted. The modal affordances of textbook representations were identified, characterized, and compared across the four physics textbook categories in the context of their support of problem-solving. Keywords: college science, science textbooks, multimodal learning theory, thermodynamics, representations

Exploring context and content links in social media: a latent space method.

PubMed

Qi, Guo-Jun; Aggarwal, Charu; Tian, Qi; Ji, Heng; Huang, Thomas S

2012-05-01

Social media networks contain both content and context-specific information. Most existing methods work with either of the two for the purpose of multimedia mining and retrieval. In reality, both content and context information are rich sources of information for mining, and the full power of mining and processing algorithms can be realized only with the use of a combination of the two. This paper proposes a new algorithm which mines both context and content links in social media networks to discover the underlying latent semantic space. This mapping of the multimedia objects into latent feature vectors enables the use of any off-the-shelf multimedia retrieval algorithms. Compared to the state-of-the-art latent methods in multimedia analysis, this algorithm effectively solves the problem of sparse context links by mining the geometric structure underlying the content links between multimedia objects. Specifically for multimedia annotation, we show that an effective algorithm can be developed to directly construct annotation models by simultaneously leveraging both context and content information based on latent structure between correlated semantic concepts. We conduct experiments on the Flickr data set, which contains user tags linked with images. We illustrate the advantages of our approach over the state-of-the-art multimedia retrieval techniques.

Few-Body Techniques Using Momentum Space for Bound and Continuum States

NASA Astrophysics Data System (ADS)

Yamashita, M. T.; Rosa, D. S.; Sandoval, J. H.

2018-05-01

This article is based on the notes (arxiv:1710.11228) written for a set of three lectures given in a school at the Max Planck Institute for the Physics of Complex Systems in October/2017 before the workshop "Critical Stability of Quantum Few-Body Systems". The last part of the article includes the specific topic presented in the workshop related to the dimensional effects in three-body systems. These notes are primarily dedicated to the students and are only a tentative to show a technique, among many others, to solve problems in a very rich area of the contemporary physics—the Few-Body Physics.

Multiple representations and free-body diagrams: Do students benefit from using them?

NASA Astrophysics Data System (ADS)

Rosengrant, David R.

2007-12-01

Introductory physics students have difficulties understanding concepts and solving problems. When they solve problems, they use surface features of the problems to find an equation to calculate a numerical answer often not understanding the physics in the problem. How do we help students approach problem solving in an expert manner? A possible answer is to help them learn to represent knowledge in multiple ways and then use these different representations for conceptual understanding and problem solving. This solution follows from research in cognitive science and in physics education. However, there are no studies in physics that investigate whether students who learn to use multiple representations are in fact better problem solvers. This study focuses on one specific representation used in physics--a free body diagram. A free-body diagram is a graphical representation of forces exerted on an object of interest by other objects. I used the free-body diagram to investigate five main questions: (1) If students are in a course where they consistently use free body diagrams to construct and test concepts in mechanics, electricity and magnetism and to solve problems in class and in homework, will they draw free-body diagrams on their own when solving exam problems? (2) Are students who use free-body diagrams to solve problems more successful then those who do not? (3) Why do students draw free-body diagrams when solving problems? (4) Are students consistent in constructing diagrams for different concepts in physics and are they consistent in the quality of their diagrams? (5) What are possible relationships between features of a problem and how likely a student will draw a free body diagram to help them solve the problem? I utilized a mixed-methods approach to answer these questions. Questions 1, 2, 4 and 5 required a quantitative approach while question 3 required a qualitative approach, a case study. When I completed my study, I found that if students are in an environment which fosters the use of representations for problem solving and for concept development, then the majority of students will consistently construct helpful free-body diagrams and use them on their own to solve problems. Additionally, those that construct correct free-body diagrams are significantly more likely to successfully solve the problem. Finally, those students that are high achieving tend to use diagrams more and for more reasons then students who have low course grades. These findings will have major impacts on how introductory physics instructors run their classes and how curriculums are designed. These results favor a problem solving strategy that is rich with representations.

The Caregiving Context in Institution-Reared and Family-Reared Infants and Toddlers in Romania

ERIC Educational Resources Information Center

Smyke, Anna T.; Koga, Sebastian F.; Johnson, Dana E.; Fox, Nathan A.; Marshall, Peter J.; Nelson, Charles A.; Zeanah, Charles H.

2007-01-01

Background: We assess individual differences in the caregiving environments of young children being raised in institutions in Romania in relation to developmental characteristics such as physical growth, cognitive development, emotional expression, and problem and competence behaviors. Method: Videotaped observations of the child and favorite…

Problems, Solutions, and Strategies Reported by Users of Transcutaneous Electrical Nerve Stimulation for Chronic Musculoskeletal Pain: Qualitative Exploration Using Patient Interviews.

PubMed

Gladwell, Peter William; Badlan, Kathryn; Cramp, Fiona; Palmer, Shea

2016-07-01

Transcutaneous electrical nerve stimulation (TENS) could offer a non-drug form of pain relief, but there is no consensus regarding its effectiveness for chronic musculoskeletal pain or chronic low back pain. A recent review of previous trial methods identified significant problems with low treatment fidelity. There is little information available to inform the development of a pragmatic implementation design for a TENS evaluation. The aim of this study was to explore the experiences of patients who were receiving secondary care in a pain clinic and who had expertise in using TENS to manage chronic musculoskeletal pain. These key informants were selected because they had the potential to generate knowledge that could inform research design and clinical practice. A qualitative method using individual semistructured interviews with open questions was selected for its capacity to generate rich data. Semistructured interviews were conducted with 9 patients (6 women, 3 men). Thematic analysis was used as the primary data analysis method, and this analysis was enhanced by a case-level analysis of the context and processes of TENS use of each individual. Data analysis indicated that patients learned to address a range of problems in order to optimize TENS use. Patients may need to personalize the positioning of electrodes and the TENS settings and to readjust them over time. Patients learned to use TENS in a strategic manner, and the outcomes of each strategy varied. The findings indicated that a pragmatic TENS evaluation may need to incorporate a learning phase to allow patients to optimize this complex pattern of TENS usage, and evaluation may need to be sensitive to the outcomes of strategic use. These findings also have implications for clinical practice. © 2016 American Physical Therapy Association.

Internet computer coaches for introductory physics problem solving

NASA Astrophysics Data System (ADS)

Xu Ryan, Qing

The ability to solve problems in a variety of contexts is becoming increasingly important in our rapidly changing technological society. Problem-solving is a complex process that is important for everyday life and crucial for learning physics. Although there is a great deal of effort to improve student problem solving skills throughout the educational system, national studies have shown that the majority of students emerge from such courses having made little progress toward developing good problem-solving skills. The Physics Education Research Group at the University of Minnesota has been developing Internet computer coaches to help students become more expert-like problem solvers. During the Fall 2011 and Spring 2013 semesters, the coaches were introduced into large sections (200+ students) of the calculus based introductory mechanics course at the University of Minnesota. This dissertation, will address the research background of the project, including the pedagogical design of the coaches and the assessment of problem solving. The methodological framework of conducting experiments will be explained. The data collected from the large-scale experimental studies will be discussed from the following aspects: the usage and usability of these coaches; the usefulness perceived by students; and the usefulness measured by final exam and problem solving rubric. It will also address the implications drawn from this study, including using this data to direct future coach design and difficulties in conducting authentic assessment of problem-solving.

A New Framework for Analysis of Coevolutionary Systems-Directed Graph Representation and Random Walks.

PubMed

Chong, Siang Yew; Tiňo, Peter; He, Jun; Yao, Xin

2017-11-20

Studying coevolutionary systems in the context of simplified models (i.e., games with pairwise interactions between coevolving solutions modeled as self plays) remains an open challenge since the rich underlying structures associated with pairwise-comparison-based fitness measures are often not taken fully into account. Although cyclic dynamics have been demonstrated in several contexts (such as intransitivity in coevolutionary problems), there is no complete characterization of cycle structures and their effects on coevolutionary search. We develop a new framework to address this issue. At the core of our approach is the directed graph (digraph) representation of coevolutionary problems that fully captures structures in the relations between candidate solutions. Coevolutionary processes are modeled as a specific type of Markov chains-random walks on digraphs. Using this framework, we show that coevolutionary problems admit a qualitative characterization: a coevolutionary problem is either solvable (there is a subset of solutions that dominates the remaining candidate solutions) or not. This has an implication on coevolutionary search. We further develop our framework that provides the means to construct quantitative tools for analysis of coevolutionary processes and demonstrate their applications through case studies. We show that coevolution of solvable problems corresponds to an absorbing Markov chain for which we can compute the expected hitting time of the absorbing class. Otherwise, coevolution will cycle indefinitely and the quantity of interest will be the limiting invariant distribution of the Markov chain. We also provide an index for characterizing complexity in coevolutionary problems and show how they can be generated in a controlled manner.

Book Review: Book review

NASA Astrophysics Data System (ADS)

Wüthrich, Christian

Symmetry considerations stand at the core of classical and quantum physics. No modern-and few older-physical theories forgo the immense services that these considerations offer. It is therefore only natural that philosophers of physics have increasingly started to study the motivations for, as well as the technical implementations and the interpretative implications of, symmetries in fundamental physics. Apart from the extraordinary foundational interest of symmetries, they provide a vehicle to study more general philosophical issues such as the relation between the physical world and its representations and between physics and mathematics. Moreover, traditional problems in metaphysics and philosophy of science such as the nature and status of laws of nature, scientific realism, and determinism naturally arise in, and enjoy substantial fertilisation from, the context of symmetries in physics.

Facilitating students' application of the integral and the area under the curve concepts in physics problems

NASA Astrophysics Data System (ADS)

Nguyen, Dong-Hai

This research project investigates the difficulties students encounter when solving physics problems involving the integral and the area under the curve concepts and the strategies to facilitate students learning to solve those types of problems. The research contexts of this project are calculus-based physics courses covering mechanics and electromagnetism. In phase I of the project, individual teaching/learning interviews were conducted with 20 students in mechanics and 15 students from the same cohort in electromagnetism. The students were asked to solve problems on several topics of mechanics and electromagnetism. These problems involved calculating physical quantities (e.g. velocity, acceleration, work, electric field, electric resistance, electric current) by integrating or finding the area under the curve of functions of related quantities (e.g. position, velocity, force, charge density, resistivity, current density). Verbal hints were provided when students made an error or were unable to proceed. A total number of 140 one-hour interviews were conducted in this phase, which provided insights into students' difficulties when solving the problems involving the integral and the area under the curve concepts and the hints to help students overcome those difficulties. In phase II of the project, tutorials were created to facilitate students' learning to solve physics problems involving the integral and the area under the curve concepts. Each tutorial consisted of a set of exercises and a protocol that incorporated the helpful hints to target the difficulties that students expressed in phase I of the project. Focus group learning interviews were conducted to test the effectiveness of the tutorials in comparison with standard learning materials (i.e. textbook problems and solutions). Overall results indicated that students learning with our tutorials outperformed students learning with standard materials in applying the integral and the area under the curve concepts to physics problems. The results of this project provide broader and deeper insights into students' problem solving with the integral and the area under the curve concepts and suggest strategies to facilitate students' learning to apply these concepts to physics problems. This study also has significant implications for further research, curriculum development and instruction.

Geometric Reasoning in an Active-Engagement Upper-Division E&M Classroom

NASA Astrophysics Data System (ADS)

Cerny, Leonard Thomas

A combination of theoretical perspectives is used to create a rich description of student reasoning when facing a highly-geometric electricity and magnetism problem in an upper-division active-engagement physics classroom at Oregon State University. Geometric reasoning as students encounter problem situations ranging from familiar to novel is described using van Zee and Manogue's (2010) ethnography of communication. Bing's (2008) epistemic framing model is used to illuminate how students are framing what they are doing and whether or not they see the problem as geometric. Kuo, Hull, Gupta, and Elby's (2010) blending model and Krutetskii's (1976) model of harmonic reasoning are used to illuminate ways students show problem-solving expertise. Sayer and Wittmann's (2008) model is used to show how resource plasticity impacts students' geometric reasoning and the degree to which students accept incorrect results.

What is occupational therapy’s role in addressing sleep problems among older adults?

PubMed Central

Leland, Natalie E.; Marcione, Nicole; Niemiec, Stacey L. Schepens; Don Fogelberg, Kaivalya Kelkar

2014-01-01

Sleep problems, prevalent among older adults, are associated with poor outcomes and high healthcare costs. In 2008, rest and sleep became its own area of occupation in the AOTA Occupational Therapy Practice Framework. This scoping review examined a broad context of sleep research in order to highlight efficacious interventions for older adults that fall within the occupational therapy scope of practice and present an agenda for research and practice. Four sleep intervention areas clearly aligned with the Practice Framework, including cognitive behavioral therapy for insomnia, physical activity, and multi-component interventions. Occupational therapy is primed to address sleep problems by targeting the context and environment, performance patterns, and limited engagement in evening activities that may contribute to poor sleep. Occupational therapy researchers and clinicians need to work collaboratively to establish the evidence-base for occupation-centered sleep interventions in order to improve the health and quality of life of the older adult. PMID:24844879

The use of multiple representations and visualizations in student learning of introductory physics: An example from work and energy

NASA Astrophysics Data System (ADS)

Zou, Xueli

In the past three decades, physics education research has primarily focused on student conceptual understanding; little work has been conducted to investigate student difficulties in problem solving. In cognitive science and psychology, however, extensive studies have explored the differences in problem solving between experts and naive students. A major finding indicates that experts often apply qualitative representations in problem solving, but that novices use an equation-centered method. This dissertation describes investigations into the use of multiple representations and visualizations in student understanding and problem solving with the concepts of work and energy. A multiple-representation strategy was developed to help students acquire expertise in solving work-energy problems. In this approach, a typical work-energy problem is considered as a physical process. The process is first described in words-the verbal representation of the process. Next, a sketch or a picture, called a pictorial representation, is used to represent the process. This is followed by work-energy bar charts-a physical representation of the same processes. Finally, this process is represented mathematically by using a generalized work-energy equation. In terms of the multiple representations, the goal of solving a work- energy problem is to represent the physical process the more intuitive pictorial and diagrammatic physical representations. Ongoing assessment of student learning indicates that this multiple-representation technique is more effective than standard instruction methods in student problem solving. visualize this difficult-to-understand concept, a guided- inquiry learning activity using a pair of model carts and an experiment problem using a sandbag were developed. Assessment results have shown that these research-based materials are effective in helping students visualize this concept and give a pictorial idea of ``where the kinetic energy goes'' during inelastic collisions. The research and curriculum development was conducted in the context of the introductory calculus-based physics course. Investigations were carried out using common physics education research tools, including open-ended surveys, written test questions, and individual student interviews.

Amygdala activity for the modulation of goal-directed behavior in emotional contexts

PubMed Central

Kunimatsu, Jun; Hikosaka, Okihide

2018-01-01

Choosing valuable objects and rewarding actions is critical for survival. While such choices must be made in a way that suits the animal’s circumstances, the neural mechanisms underlying such context-appropriate behavior are unclear. To address this question, we devised a context-dependent reward-seeking task for macaque monkeys. Each trial started with the appearance of one of many visual scenes containing two or more objects, and the monkey had to choose the good object by saccade to get a reward. These scenes were categorized into two dimensions of emotional context: dangerous versus safe and rich versus poor. We found that many amygdala neurons were more strongly activated by dangerous scenes, by rich scenes, or by both. Furthermore, saccades to target objects occurred more quickly in dangerous than in safe scenes and were also quicker in rich than in poor scenes. Thus, amygdala neuronal activity and saccadic reaction times were negatively correlated in each monkey. These results suggest that amygdala neurons facilitate targeting saccades predictably based on aspects of emotional context, as is necessary for goal-directed and social behavior. PMID:29870524

Aristotelian Physics in the Context of Teaching Science: A Historical-Philosophical Approach

NASA Astrophysics Data System (ADS)

Lombardi, Olimpia

Nowadays in the community of researchers there is a practically unanimous consensus about the relevance of the history of science to the educational process. In this context, Aristotelian physics was rediscovered and reassessed for didactic purposes. But unfortunately, it is very often presented in a rather fragmentary and oversimplified way that distorts the true meaning of Aristotelian concepts. Facing this problem, the purpose of the present paper is to point out some blunders that originate in the partial reading of Aristotle's work. Particularly, it intends to contribute to the following points: (i) to warn against a hurried identification of pre-scientific notions and Aristotelian physical concepts; (ii) to promote an epistemologically not naïve and historiographically not anachronic interpretation of Aristotle's work on physics, both in the theoretical and in the methodological aspects; (iii) to warn against the interpretative confusion that arises from projecting the conceptual frame of contemporary science on Aristotelian physics, ignoring Aristotle's natural philosophy as a whole; (iv) to show the need of understanding the metaphysical foundations of the Aristotelian system; (v) to promote a return to the reading of the original texts.

Effects of preprocessing Landsat MSS data on derived features

NASA Technical Reports Server (NTRS)

Parris, T. M.; Cicone, R. C.

1983-01-01

Important to the use of multitemporal Landsat MSS data for earth resources monitoring, such as agricultural inventories, is the ability to minimize the effects of varying atmospheric and satellite viewing conditions, while extracting physically meaningful features from the data. In general, the approaches to the preprocessing problem have been derived from either physical or statistical models. This paper compares three proposed algorithms; XSTAR haze correction, Color Normalization, and Multiple Acquisition Mean Level Adjustment. These techniques represent physical, statistical, and hybrid physical-statistical models, respectively. The comparisons are made in the context of three feature extraction techniques; the Tasseled Cap, the Cate Color Cube. and Normalized Difference.

Factors associated with different smoking status in European adolescents: results of the SEYLE study.

PubMed

Banzer, Raphaela; Haring, C; Buchheim, A; Oehler, S; Carli, V; Wasserman, C; Kaess, M; Apter, A; Balazs, J; Bobes, J; Brunner, R; Corcoran, P; Cosman, D; Hoven, C W; Kahn, J P; Keeley, H S; Postuvan, V; Podlogar, T; Sisask, M; Värnik, A; Sarchiapone, M; Wasserman, D

2017-11-01

Early onset and long-term smoking are associated with physical and psychological health problems. The aim of the presented analysis was to investigate risk and influencing factors for different smoking status in a big sample of European adolescents. In the context of the "saving and empowering young lives in Europe" (SEYLE) study we surveyed 12,328 adolescents at the age of 13-17 from 11 countries. The survey took place in a school-based context using a questionnaire. Overall 58% reported the onset of ever-smoking under the age of 14 and 30.9% smoke on a daily basis. Multinomial logistic regression model showed significant positive associations between adolescent smoking and internalizing problems (suicidal behavior, direct self-injurious behavior, anxiety), externalizing problems (conduct problems, hyperactivity, substance consumption) and family problems (parental substance consumption, broken home). Our data show that smoking among adolescents is still a major public health problem and adolescents who smoke are at higher risk for mental problems. Further, adolescent smoking is associated with broken home families and parental behaviors. Therefore, early preventive measures are necessary not only for adolescents, but also for their parents.

Probability versus representativeness in infancy: can infants use naïve physics to adjust population base rates in probabilistic inference?

PubMed

Denison, Stephanie; Trikutam, Pallavi; Xu, Fei

2014-08-01

A rich tradition in developmental psychology explores physical reasoning in infancy. However, no research to date has investigated whether infants can reason about physical objects that behave probabilistically, rather than deterministically. Physical events are often quite variable, in that similar-looking objects can be placed in similar contexts with different outcomes. Can infants rapidly acquire probabilistic physical knowledge, such as some leaves fall and some glasses break by simply observing the statistical regularity with which objects behave and apply that knowledge in subsequent reasoning? We taught 11-month-old infants physical constraints on objects and asked them to reason about the probability of different outcomes when objects were drawn from a large distribution. Infants could have reasoned either by using the perceptual similarity between the samples and larger distributions or by applying physical rules to adjust base rates and estimate the probabilities. Infants learned the physical constraints quickly and used them to estimate probabilities, rather than relying on similarity, a version of the representativeness heuristic. These results indicate that infants can rapidly and flexibly acquire physical knowledge about objects following very brief exposure and apply it in subsequent reasoning. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Spatial patterns of species richness in New World coral snakes and the metabolic theory of ecology

NASA Astrophysics Data System (ADS)

Terribile, Levi Carina; Diniz-Filho, José Alexandre Felizola

2009-03-01

The metabolic theory of ecology (MTE) has attracted great interest because it proposes an explanation for species diversity gradients based on temperature-metabolism relationships of organisms. Here we analyse the spatial richness pattern of 73 coral snake species from the New World in the context of MTE. We first analysed the association between ln-transformed richness and environmental variables, including the inverse transformation of annual temperature (1/ kT). We used eigenvector-based spatial filtering to remove the residual spatial autocorrelation in the data and geographically weighted regression to account for non-stationarity in data. In a model I regression (OLS), the observed slope between ln-richness and 1/ kT was -0.626 ( r2 = 0.413), but a model II regression generated a much steeper slope (-0.975). When we added additional environmental correlates and the spatial filters in the OLS model, the R2 increased to 0.863 and the partial regression coefficient of 1/ kT was -0.676. The GWR detected highly significant non-stationarity, in data, and the median of local slopes of ln-richness against 1/ kT was -0.38. Our results expose several problems regarding the assumptions needed to test MTE: although the slope of OLS fell within that predicted by the theory and the dataset complied with the assumption of temperature-independence of average body size, the fact that coral snakes consist of a restricted taxonomic group and the non-stationarity of slopes across geographical space makes MTE invalid to explain richness in this case. Also, it is clear that other ecological and historical factors are important drivers of species richness patterns and must be taken into account both in theoretical modeling and data analysis.

Associations between children's social functioning and physical activity participation are not mediated by social acceptance: a cross-sectional study.

PubMed

Sebire, Simon J; Jago, Russell; Fox, Kenneth R; Page, Angie S; Brockman, Rowan; Thompson, Janice L

2011-09-30

Physical activity (PA) during childhood often occurs in social contexts. As such, children's ability to develop and maintain friendship groups may be important in understanding their PA. This paper investigates the associations among children's social functioning, and physical activity and whether perceptions of social acceptance mediate any social functioning-PA association. A cross sectional survey in which 652 10-11 year olds self-reported their peer (e.g. difficulties with friends) and conduct (e.g. anger/aggression) problems, prosocial behaviours (e.g. being kind to others) and perceptions of social acceptance. Physical activity was objectively assessed by Actigraph GT1M accelerometers to estimate counts per minute, (CPM) and minutes of moderate-to-vigorous physical activity (MVPA). Linear regression analyses were conducted to investigate associations between social functioning and PA. Indirect effects were analysed to explore mediation by social acceptance. Among boys, peer problems were negatively associated with CPM and MVPA and conduct problems were positively associated with CPM and MVPA. Prosocial behaviour was unrelated to PA in boys. Social functioning was not associated with PA among girls. Social acceptance did not mediate the social functioning-PA relationship. Boys' conduct and peer problems were associated positively and negatively respectively with their PA but this relationship was not mediated by perceptions of social acceptance. Future research should study alternative mediators to understand the processes underpinning this relationship.

A Worksheet to Enhance Students’ Conceptual Understanding in Vector Components

NASA Astrophysics Data System (ADS)

Wutchana, Umporn; Emarat, Narumon

2017-09-01

With and without physical context, we explored 59 undergraduate students’conceptual and procedural understanding of vector components using both open ended problems and multiple choice items designed based on research instruments used in physics education research. The results showed that a number of students produce errors and revealed alternative conceptions especially when asked to draw graphical form of vector components. It indicated that most of them did not develop a strong foundation of understanding in vector components and could not apply those concepts to such problems with physical context. Based on the findings, we designed a worksheet to enhance the students’ conceptual understanding in vector components. The worksheet is composed of three parts which help students to construct their own understanding of definition, graphical form, and magnitude of vector components. To validate the worksheet, focus group discussions of 3 and 10 graduate students (science in-service teachers) had been conducted. The modified worksheet was then distributed to 41 grade 9 students in a science class. The students spent approximately 50 minutes to complete the worksheet. They sketched and measured vectors and its components and compared with the trigonometry ratio to condense the concepts of vector components. After completing the worksheet, their conceptual model had been verified. 83% of them constructed the correct model of vector components.

Investigating the Role of Traditional Children's Games in Teaching Ten Universal Values in Turkey

ERIC Educational Resources Information Center

Aypay, Ayse

2016-01-01

Statement of the Problem: Children are constantly stimulated in different developmental areas through playing games with other children or adults. Play can provide a context wherein children achieve deep learning through the integration of intellectual, physical, moral, and spiritual values and commit themselves to learning, developing, and…

Children with Autism Spectrum Disorder Have an Exceptional Explanatory Drive

ERIC Educational Resources Information Center

Rutherford, M. D.; Subiaul, Francys

2016-01-01

An "explanatory drive" motivates children to explain ambiguity. Individuals with autism spectrum disorders are interested in how systems work, but it is unknown whether they have an explanatory drive. We presented children with and without autism spectrum disorder unsolvable problems in a physical and in a social context and evaluated…

Children and Violence: The Role of Children's Regulation in the Marital Aggression-Child Adjustment Link

ERIC Educational Resources Information Center

Cummings, E. Mark; El-Sheikh, Mona; Kouros, Chrystyna D.; Buckhalt, Joseph A.

2009-01-01

Exposure to marital psychological and physical abuse has been established as a risk factor for children's socio-emotional, behavioral, and cognitive problems. Understanding the processes by which children develop symptoms of psychopathology and deficits in cognitive functioning in the context of marital aggression is imperative for developing…

Nicotinamide-rich diet improves physical endurance by up-regulating SUR2A in the heart

PubMed Central

Sukhodub, Andriy; Sudhir, Rajni; Du, Qingyou; Jovanović, Sofija; Reyes, Santiago; Jovanović, Aleksandar

2011-01-01

Abstract SUR2A is an ATP-binding protein that serves as a regulatory subunit of cardioprotective ATP-sensitive K+ (KATP) channels. Based on signalling pathway regulating SUR2A expression and SUR2A role in regulating numbers of fully assembled KATP channels, we have suggested that nicotinamide-rich diet could improve physical endurance by stimulating SUR2A expression. We have found that mice on nicotinamide-rich diet significantly improved physical endurance, which was associated with significant increase in expression of SUR2A. Transgenic mice with solely overexpressed SUR2A on control diet had increased physical endurance in a similar manner as the wild-type mice on nicotinamide-rich diet. The experiments focused on action membrane potential and intracellular Ca2+ concentration have demonstrated that increased SUR2A expression was associated with the activation of sarcolemmal KATP channels and steady Ca2+ levels in cardiomyocytes in response to β-adrenergic stimulation. In contrast, the same challenge in the wild-type was characterized by a lack of the channel activation and rise in intracellular Ca2+. Nicotinamide-rich diet was ineffective to increase physical endurance in mice lacking KATP channels. This study has shown that nicotinamide-rich diet improves physical endurance by increasing expression of SUR2A and that this is a sole mechanism of the nicotinamide-rich diet effect. The obtained results suggest that oral nicotinamide is a regulator of SUR2A expression and has a potential as a drug that can improve physical endurance in conditions where this effect would be desirable. PMID:20731746

The globalization of epidemiology: introductory remarks.

PubMed

Pearce, Neil

2004-10-01

We are all living in the era of globalization, and like it or not, it is going to change the way we practice epidemiology, the kinds of questions we ask, and the methods we use to answer them. Increasingly, pubic health problems are being shifted from rich countries to poor countries and from rich to poor populations within Western countries. There is increasing interest and concern about the situation in non-Western populations on the part of Western epidemiologists, with regards to collaborative research, skills transfer, and 'volunteerism' to enable the 'benefits' of Western approaches to epidemiology to be shared by the non-Western world. However, most existing collaborations benefit Western epidemiologists rather than the countries in which the research is conducted. Even when research in non-Western populations is conducted as a genuine collaboration, it can too often 'export failure' from the West. On the other hand, non-Western epidemiologists are increasingly developing new and innovative approaches to health research that are more appropriate to the global public health issues they are addressing. These include recognition of the importance of context and the importance of diversity and local knowledge, and a problem-based approach to addressing the major public health problems using appropriate technology. These debates formed the background for a plenary session on 'International Epidemiology and International Health' at the recent International Epidemiological Association (IEA) meeting in Montreal, and the papers from this session are presented here. The development of a truly global epidemiology can not only better address the public health problems in non-Western populations, but can shed light on the current limitations of epidemiology in addressing the major public health problems in the West.

Students' Energy Understanding Across Biology, Chemistry, and Physics Contexts

NASA Astrophysics Data System (ADS)

Opitz, S. T.; Neumann, K.; Bernholt, S.; Harms, U.

2017-07-01

Energy is considered both as a disciplinary core idea and as a concept cutting across science disciplines. Most previous approaches studied progressing energy understanding in specific disciplinary contexts, while disregarding the relation of understanding across them. Hence, this study provides a systematic analysis of cross-disciplinary energy learning. On the basis of a cross-sectional study with n = 742 students from grades 6, 8, and 10, we analyze students' progression in understanding energy across biology, chemistry, and physics contexts. The study is guided by three hypothetical scenarios that describe how the connection between energy understanding in the three disciplinary contexts changes across grade levels. These scenarios are compared using confirmatory factor analysis (CFA). The results suggest that, from grade 6 to grade 10, energy understanding in the three disciplinary contexts is highly interrelated, thus indicating a parallel progression of energy understanding in the three disciplinary contexts. In our study, students from grade 6 onwards appeared to have few problems to apply one energy understanding across the three disciplinary contexts. These findings were unexpected, as previous research concluded that students likely face difficulties in connecting energy learning across disciplinary boundaries. Potential reasons for these results and the characteristics of the observed cross-disciplinary energy understanding are discussed in the light of earlier findings and implications for future research, and the teaching of energy as a core idea and a crosscutting concept are addressed.

Potential impacts of iron biofortification in India.

PubMed

Stein, Alexander J; Meenakshi, J V; Qaim, Matin; Nestel, Penelope; Sachdev, H P S; Bhutta, Zulfiqar A

2008-04-01

Iron deficiency is a widespread nutrition and health problem in developing countries, causing impairments in physical activity and cognitive development, as well as maternal mortality. Although food fortification and supplementation programmes have been effective in some countries, their overall success remains limited. Biofortification, that is, breeding food crops for higher micronutrient content, is a relatively new approach, which has been gaining international attention recently. We propose a methodology for ex ante impact assessment of iron biofortification, building on a disability-adjusted life years (DALYs) framework. This methodology is applied in an Indian context. Using a large and representative data set of household food consumption, the likely effects of iron-rich rice and wheat varieties are simulated for different target groups and regions. These varieties, which are being developed by an international public research consortium, based on conventional breeding techniques, might be ready for local distribution within the next couple of years. The results indicate sizeable potential health benefits. Depending on the underlying assumptions, the disease burden associated with iron deficiency could be reduced by 19-58%. Due to the relatively low institutional cost to reach the target population, the expected cost-effectiveness of iron biofortification compares favourably with other micronutrient interventions. Nonetheless, biofortification should not be seen as a substitute for other interventions. Each approach has its particular strengths, so they complement one another.

Dynamical dark energy vs. Λ = const in light of observations

NASA Astrophysics Data System (ADS)

Solà Peracaula, Joan; de Cruz Pérez, Javier; Gómez-Valent, Adrià

2018-02-01

After about two decades of the first observational papers confirming the accelerated expansion of the universe, we are still facing the question whether the cause of it is a rigid cosmological constant Λ-term or a mildly evolving dynamical dark energy (DDE). While studies focusing mainly on CMB measurements do not perceive signs of physics beyond the ΛCDM, in this work we show that if we take a large string SNIa+BAO+H(z)+LSS+CMB of modern cosmological observations, in which not only the CMB but also a rich sample of large-scale structure formation data are included, one can extract ∼3.3σ signs of DDE using a simple XCDM parameterization. These signs can be enhanced up to near 3.8σ in the context of the running vacuum model (RVM), in which the vacuum energy density is in interaction with dark matter. Recently, the RVM has been shown to provide an efficient and economical solution to the σ8 -tension, which is one of the intriguing phenomenological problems that has not been possible to solve within the ΛCDM so far. This fact contributes to strengthen the possibility that dynamical vacuum energy, or in general DDE, could be presently favored by the observations.

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

Goriely, S.; Bauswein, A.; Janka, H.-T.

About half of the nuclei heavier than iron observed in nature are produced by the so-called rapid neutron capture process, or r-process, of nucleosynthesis. The identification of the astrophysics site and the specific conditions in which the r-process takes place remains, however, one of the still-unsolved mysteries of modern astrophysics. Another underlying difficulty associated with our understanding of the r-process concerns the uncertainties in the predictions of nuclear properties for the few thousands exotic neutron-rich nuclei involved, for which essentially no experimental data exist. The present paper emphasizes some important future challenges faced by nuclear physics in this problem, particularlymore » in the determination of the nuclear structure properties of exotic neutron-rich nuclei as well as their radiative neutron capture rates and their fission probabilities. These quantities are particularly relevant to determine the composition of the matter resulting from the r-process. Both the astrophysics and the nuclear physics difficulties are critically reviewed with special attention paid to the r-process taking place during the decompression of neutron star matter following the merging of two neutron stars.« less

Self-Regulation in the Midst of Complexity: A Case Study of High School Physics Students Engaged in Ill-Structured Problem Solving

NASA Astrophysics Data System (ADS)

Milbourne, Jeffrey David

The purpose of this dissertation study was to explore the experiences of high school physics students who were solving complex, ill-structured problems, in an effort to better understand how self-regulatory behavior mediated the project experience. Consistent with Voss, Green, Post, and Penner's (1983) conception of an ill-structured problem in the natural sciences, the 'problems' consisted of scientific research projects that students completed under the supervision of a faculty mentor. Zimmerman and Campillo's (2003) self-regulatory framework of problem solving provided a holistic guide to data collection and analysis of this multi-case study, with five individual student cases. The study's results are explored in two manuscripts, each targeting a different audience. The first manuscript, intended for the Science Education Research community, presents a thick, rich description of the students' project experiences, consistent with a qualitative, case study analysis. Findings suggest that intrinsic interest was an important self-regulatory factor that helped motivate students throughout their project work, and that the self-regulatory cycle of forethought, performance monitoring, and self-reflection was an important component of the problem-solving process. Findings also support the application of Zimmerman and Campillo's framework to complex, ill-structured problems, particularly the cyclical nature of the framework. Finally, this study suggests that scientific research projects, with the appropriate support, can be a mechanism for improving students' selfregulatory behavior. The second manuscript, intended for Physics practitioners, combines the findings of the first manuscript with the perspectives of the primary, on-site research mentor, who has over a decade's worth of experience mentoring students doing physics research. His experience suggests that a successful research experience requires certain characteristics, including: a slow, 'on-ramp' to the research experience, space to experience productive failure, and an opportunity to enjoy the work they are doing.

Introductory Physics Students' Physics and Mathematics Epistemologies

NASA Astrophysics Data System (ADS)

Scanlon, Erin M.

The purpose of this three study dissertation is to investigate why students are enrolled in introductory physics courses experience difficulties in being successful; one possible source of their difficulties is related to their epistemology. In order to investigate students' epistemologies about mathematics and physics, students were observed solving physics problems in groups during a laboratory course (study 1) and while solving physics and mathematics problems individually during office-hour sessions (study 2). The Epistemological Resources theoretical framework was employed (Hammer & Elby, 2002). Using emergent and a priori epistemological resource operationalizations (Jones, 2015), 25 distinct epistemological resources were identified in study 1. Differences in physics epistemological resource usage between students of varying academic background (as measured by their number of previously completed mathematics and science classes were identified. By employing an external (Jones, 2015) and internal (Scanlon, 2016) a priori epistemological resource coding scheme, a total of 17 distinct epistemological resources were identified in study 2. The data were sampled to compare the mathematics and physics epistemological resource usage of participants with consistent and inconsistent sign usage in an energy conservation physics problem in order to provide a meaningful context for discussion. Participants of the same sign usage group employed epistemological resources similarly. Conversely, participants in different groups had significantly different physics epistemological resource usage patterns. Finally, student epistemological resource usage patterns from the first two studies were compared to course outcomes in order to determine implications for practice (study 3). Educators must be aware of and address the epistemological underpinnings of students' difficulties in introductory physics courses.

Relationship between cancer-related fatigue and physical activity in inpatient cancer rehabilitation.

PubMed

Kummer, Franziska; Catuogno, Silvio; Perseus, Josef M; Bloch, Wilhelm; Baumann, Freerk T

2013-08-01

Fatigue is a serious problem for the majority of patients with cancer. In this context, several studies have shown benefits of physical activity during and following treatment. However, uncertainties remain regarding the optimal type and duration of physical activity. Therefore, this study examined the relationship between cancer-related fatigue and physical activity in the course of inpatient rehabilitation. Fatigue (Multidimensional Fatigue Inventory) and physical activity (Freiburg Questionnaire of Physical Activity) were assessed in a consecutive series of 35 patients with cancer attending oncological inpatient rehabilitation during a six-month study period. The three-week rehabilitation program included daily exercise therapy consisting of aerobic endurance training, moderate resistance training, coordination exercises, relaxation training and individual physiotherapy. At discharge, a significant improvement in each dimension of cancer-related fatigue (p=0.001-0.003) and a significant increase of physical activity levels (p=0.001) were observed. A small, but significant negative correlation was found between cancer-related fatigue and the level of physical activity (R=-0.438, p=0.004). The largest effects were associated with a weekly energy expenditure of 3000 kcal through physical activity. The results support a non-linear dose-response relationship between cancer-related fatigue and physical activity. Since this is the first study providing specific exercise recommendations for an effective treatment of cancer-related fatigue in the context of inpatient rehabilitation, further research is required to validate the observed trends.

The Math You Need, When You Need It: Student-Centered Web Resources Designed to Decrease Math Review and Increase Quantitative Geology in the Classroom

NASA Astrophysics Data System (ADS)

Wenner, J. M.; Baer, E. M.

2007-12-01

Introductory geoscience courses are rife with quantitative concepts from graphing to rates to unit conversions. Recent research suggests that supplementary mathematical instruction increases post-secondary students' retention and performance in science courses. Nonetheless, many geoscience faculty feel that they do not have enough time to cover all the geoscience content, let alone covering the math they often feel students should have learned before reaching their classes. We present our NSF-funded effort to create web modules for students that address these concerns. Our web resources focus on both student performance and faculty time issues by building students' quantitative skills through web-based, self-paced modular tutorials. Each module can be assigned to individual students who have demonstrated on a pre-test that they are in need of supplemental instruction. The pre-test involves problems that place mathematical concepts in a geoscience context and determines the students who need the most support with these skills. Students needing support are asked to complete a three-pronged web-based module just before the concept is needed in class. The three parts of each tutorial include: an explanation of the mathematics, a page of practice problems and an on-line quiz that is graded and sent to the instructor. Each of the modules is steeped in best practices in mathematics and geoscience education, drawing on multiple contexts and utilizing technology. The tutorials also provide students with further resources so that they can explore the mathematics in more depth. To assess the rigor of this program, students are given the pre-test again at the end of the course. The uniqueness of this program lies in a rich combination of mathematical concepts placed in multiple geoscience contexts, giving students the opportunity to explore the way that math relates to the physical world. We present several preliminary modules dealing with topics common in introductory geoscience courses. We seek feedback from faculty teaching all levels of geoscience addressing several questions: In what math/geoscience topics do you feel students need supplemental instruction? Where do students come up against quantitative topics that make them drop the class or perform poorly? Would you be willing to review or help us to test these modules in your class?

It's NOT rocket science: rethinking our metaphors for research in health professions education.

PubMed

Regehr, Glenn

2010-01-01

The health professional education community is struggling with a number of issues regarding the place and value of research in the field, including: the role of theory-building versus applied research; the relative value of generalisable versus contextually rich, localised solutions, and the relative value of local versus multi-institutional research. In part, these debates are limited by the fact that the health professional education community has become deeply entrenched in the notion of the physical sciences as presenting a model for 'ideal' research. The resulting emphasis on an 'imperative of proof' in our dominant research approaches has translated poorly to the domain of education, with a resulting denigration of the domain as 'soft' and 'unscientific' and a devaluing of knowledge acquired to date. Similarly, our adoption of the physical sciences''imperative of generalisable simplicity' has created difficulties for our ability to represent well the complexity of the social interactions that shape education and learning at a local level. Using references to the scientific paradigms associated with the physical sciences, this paper will reconsider the place of our current goals for education research in the production and evolution of knowledge within our community, and will explore the implications for enhancing the value of research in health professional education. Reorienting education research from its alignment with the imperative of proof to one with an imperative of understanding, and from the imperative of simplicity to an imperative of representing complexity well may enable a shift in research focus away from a problematic search for proofs of simple generalisable solutions to our collective problems, towards the generation of rich understandings of the complex environments in which our collective problems are uniquely embedded.

Compensation Techniques in Accelerator Physics

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

Sayed, Hisham Kamal

2011-05-01

Accelerator physics is one of the most diverse multidisciplinary fields of physics, wherein the dynamics of particle beams is studied. It takes more than the understanding of basic electromagnetic interactions to be able to predict the beam dynamics, and to be able to develop new techniques to produce, maintain, and deliver high quality beams for different applications. In this work, some basic theory regarding particle beam dynamics in accelerators will be presented. This basic theory, along with applying state of the art techniques in beam dynamics will be used in this dissertation to study and solve accelerator physics problems. Twomore » problems involving compensation are studied in the context of the MEIC (Medium Energy Electron Ion Collider) project at Jefferson Laboratory. Several chromaticity (the energy dependence of the particle tune) compensation methods are evaluated numerically and deployed in a figure eight ring designed for the electrons in the collider. Furthermore, transverse coupling optics have been developed to compensate the coupling introduced by the spin rotators in the MEIC electron ring design.« less

Physics faculty beliefs and values about the teaching and learning of problem solving. II. Procedures for measurement and analysis

NASA Astrophysics Data System (ADS)

Henderson, Charles; Yerushalmi, Edit; Kuo, Vince H.; Heller, Kenneth; Heller, Patricia

2007-12-01

To identify and describe the basis upon which instructors make curricular and pedagogical decisions, we have developed an artifact-based interview and an analysis technique based on multilayered concept maps. The policy capturing technique used in the interview asks instructors to make judgments about concrete instructional artifacts similar to those they likely encounter in their teaching environment. The analysis procedure alternatively employs both an a priori systems view analysis and an emergent categorization to construct a multilayered concept map, which is a hierarchically arranged set of concept maps where child maps include more details than parent maps. Although our goal was to develop a model of physics faculty beliefs about the teaching and learning of problem solving in the context of an introductory calculus-based physics course, the techniques described here are applicable to a variety of situations in which instructors make decisions that influence teaching and learning.

PREFACE: Theory of Fusion Plasmas, 13th Joint Varenna-Lausanne International Workshop (2012)

NASA Astrophysics Data System (ADS)

Garbet, Xavier; Sauter, Olivier

2012-12-01

The 2012 joint Varenna-Lausanne international workshop on the theory of fusion plasmas has been very fruitful. A broad variety of topics were addressed, as usual covering turbulence, MHD, edge physic, RF wave heating and a taste of astrophysics. Moreover the scope of the meeting was extended this year to include the physics of materials and diagnostics for burning plasmas. This evolution reflects the complexity of problems at hand in fusion, in particular in the context of ITER construction. Long-standing problems without immediate consequences have sometimes become an urgent matter in that context. One may quote for instance the choice of plasma facing components or the design of control systems. Another characteristic of the meeting is the interplay between various domains of plasma physics. For instance MHD modes are now currently investigated with gyrokinetic codes, kinetic effects are more and more included in MHD stability analysis, and turbulence is now accounted for in wave propagation problems. This is the proof of cross-fertilization and it is certainly a healthy sign in our community. Finally introducing some novelty in the programme does not prevent us from respecting the traditions of the meeting. As usual a good deal of the presentations were dedicated to numerical simulations. Combining advanced numerical techniques with elaborated analytical theory is certainly a trademark of the Varenna-Lausanne conference, which was respected again this year. The quality and size of the scientific production is illustrated by the 26 papers which appear in the present volume of Journal of Physics: Conference Series, all refereed. We would also like to mention another set of 20 papers to be published in Plasma Physics and Controlled Fusion. We hope the readers will enjoy this special issue of JPCS and the one to come in PPCF. Xavier Garbet and Olivier Sauter October 26, 2012

A Survey on the Feasibility of Sound Classification on Wireless Sensor Nodes

PubMed Central

Salomons, Etto L.; Havinga, Paul J. M.

2015-01-01

Wireless sensor networks are suitable to gain context awareness for indoor environments. As sound waves form a rich source of context information, equipping the nodes with microphones can be of great benefit. The algorithms to extract features from sound waves are often highly computationally intensive. This can be problematic as wireless nodes are usually restricted in resources. In order to be able to make a proper decision about which features to use, we survey how sound is used in the literature for global sound classification, age and gender classification, emotion recognition, person verification and identification and indoor and outdoor environmental sound classification. The results of the surveyed algorithms are compared with respect to accuracy and computational load. The accuracies are taken from the surveyed papers; the computational loads are determined by benchmarking the algorithms on an actual sensor node. We conclude that for indoor context awareness, the low-cost algorithms for feature extraction perform equally well as the more computationally-intensive variants. As the feature extraction still requires a large amount of processing time, we present four possible strategies to deal with this problem. PMID:25822142

Distance learning for University Physics in South Africa

NASA Astrophysics Data System (ADS)

Cilliers, J. A.; Basson, I.

1997-03-01

The University of South Africa (Unisa) is one of the largest distance education universities in the world. Teaching physics at a distance is a complex and multifaceted problem which is compounded in the South African context by the diversity of educational backgrounds of the learners involved. The fact that students are distributed over a vast geographical area, presents unique problems for the incorporation of the practical component into the curriculum. Current research involves a fundamental evaluation of the aims and objectives of the introductory laboratory. The project is based on the notion that practicals, as they have been used in most physics curricula, are not particularly effective or efficient, although they are costly both financially and logistically. Design, development and delivery of efficient study material imply that there should be agreement between what the student knows and can do, and what the material offers. An in depth profile that takes into account biographic as well as cognitive characteristics of the target group, is therefore being compiled. This paper gives an overview of the specific problems and circumstances that were identified for distance education in physics in a multi-cultural society, and proposes a new model for the incorporation of the introductory laboratory into the curriculum.

Does stress mediate the association between personal relative deprivation and gambling?

PubMed

Mishra, Sandeep; Meadows, Tyler J S

2018-04-01

Evidence has linked subjective feelings of personal relative deprivation with general gambling involvement and problem gambling tendencies. In turn, problem gambling tendencies have been linked with a wide array of damaging physical and mental health consequences. It has been theorized that the deleterious effects of perceived inequality on mental and physical health operate at the individual level through the experience of personal relative deprivation leading to psychosocial stress. We empirically examined whether the experience of perceived stress contributes to explaining the deprivation-gambling link using cross-sectional, self-reported survey data collected from a crowdsourced population of adults (n = 565). Results indicate that personal relative deprivation is associated with problem gambling tendencies (but not general gambling involvement) and that this association is mediated by perceived stress. These associations were particularly strong among participants who reported non-zero levels of problem gambling tendencies. Together, our results further emphasize the importance of individual-level social comparison reactions in the context of health. Copyright © 2017 John Wiley & Sons, Ltd.

The future of computing--new architectures and new technologies.

PubMed

Warren, P

2004-02-01

All modern computers are designed using the 'von Neumann' architecture and built using silicon transistor technology. Both architecture and technology have been remarkably successful. Yet there are a range of problems for which this conventional architecture is not particularly well adapted, and new architectures are being proposed to solve these problems, in particular based on insight from nature. Transistor technology has enjoyed 50 years of continuing progress. However, the laws of physics dictate that within a relatively short time period this progress will come to an end. New technologies, based on molecular and biological sciences as well as quantum physics, are vying to replace silicon, or at least coexist with it and extend its capability. The paper describes these novel architectures and technologies, places them in the context of the kinds of problems they might help to solve, and predicts their possible manner and time of adoption. Finally it describes some key questions and research problems associated with their use.

Psychological Coercion in Human Trafficking: An Application of Biderman's Framework.

PubMed

Baldwin, Susie B; Fehrenbacher, Anne E; Eisenman, David P

2015-09-01

This study examined coercive conditions experienced by trafficked persons in the context of Biderman's theory of coercion. We conducted semi-structured interviews with 12 adult women trafficked into Los Angeles County, from 10 countries, for domestic work and/or sex work. Participants described health problems they experienced in relation to their trafficking experience and their perceptions of conditions that caused health problems. Utilizing a framework analysis approach, we analyzed themes using Biderman's framework. Participants reported experiencing the range of nonphysical coercive tactics outlined by Biderman, including isolation, monopolization of perception, induced debility or exhaustion, threats, occasional indulgences, demonstration of omnipotence, degradation, and enforcement of trivial demands. Our analysis demonstrates how these coercion tactics reinforced the submission of trafficked persons to their traffickers even in the absence of physical force or restraints. Such psychological abuse creates extreme stress that can lead to acute and chronic, physical and mental health problems. © The Author(s) 2014.

Searching for Physics Beyond the Standard Model and Beyond

NASA Astrophysics Data System (ADS)

Abdullah, Mohammad

The hierarchy problem, convolved with the various known puzzles in particle physics, grants us a great outlook of new physics soon to be discovered. We present multiple approaches to searching for physics beyond the standard model. First, two models with a minimal amount of theoretical guidance are analyzed using existing or simulated LHC data. Then, an extension of the Minimal Supersymmetric Standard Model (MSSM) is studied with an emphasis on the cosmological implications as well as the current and future sensitivity of colliders, direct detection and indirect detection experiments. Finally, a more complete model of the MSSM is presented through which we attempt to resolve tension with observations within the context of gauge mediated supersymmetry breaking.

Physical inactivity as a policy problem: applying a concept from policy analysis to a public health issue.

PubMed

Rütten, Alfred; Abu-Omar, Karim; Gelius, Peter; Schow, Diana

2013-03-07

Despite the recent rapid development of policies to counteract physical inactivity (PI), only a small number of systematic analyses on the evolution of these policies exists. In this article we analyze how PI, as a public health issue, "translates" into a policy-making issue. First, we discuss why PI has become an increasingly important public health issue during the last two decades. We then follow Guy Peters and conceptualize PI as a "policy problem" that has the potential to be linked to policy instruments and policy impact. Analysis indicates that PI is a policy problem that i) is chronic in nature; ii) involves a high degree of political complexity; iii) can be disaggregated into smaller scales; iv) is addressed through interventions that can be difficult to "sell" to the public when their benefits are not highly divisible; v) cannot be solved by government spending alone; vi) must be addressed through a broad scope of activities; and vii) involves interdependencies among both multiple sectors and levels of government.We conclude that the new perspective on PI proposed in this article might be useful and important for i) describing and mapping policies to counteract PI in different contexts; ii) evaluating whether or not existing policy instruments are appropriate to the policy problem of PI, and iii) explaining the factors and processes that underlie policy development and implementation. More research is warranted in all these areas. In particular, we propose to focus on comparative analyses of how the problem of PI is defined and tackled in different contexts, and on the identification of truly effective policy instruments that are designed to "solve" the PI policy problem.

The complex array of antecedents of depression in women with physical disabilities: implications for clinicians.

PubMed

Nosek, Margaret A; Hughes, Rosemary B; Robinson-Whelen, Susan

2008-01-01

This article discusses the complex interrelation of elements of the physical, psychological, social, and environmental life context of women with physical disabilities and the association of these elements with significant disparities in rates of depression and access to mental health care for this population. Literature and concept review. High rates of depression in women with physical disabilities are well documented in the literature. Many elements that are disproportionately common in the lives of women with physical disabilities, including socio-economic disadvantage, functional limitations, pain and other chronic health conditions, poor diet, physical inactivity, smoking, violence, low self-esteem, sexuality problems, chronic stress, environmental barriers, and barriers to health care, have also been linked with higher rates of depression and depressive symptomatology. Depression self-management interventions tailored for women with disabilities have been developed and proven effective. Many women who must deal with the stresses surrounding an array of health problems may experience symptoms of depression without necessarily meeting the criteria for clinical depression. Psychologists, counselors, primary care physicians, specialists, and other medical and rehabilitation professionals are challenged to recognize the symptoms of depression in women with physical disabilities and assist them in obtaining appropriate psychological and pharmacological interventions.

[Can sports and physical activity promote young peoples' psychosocial health?].

PubMed

Ommundsen, Y

2000-11-30

Sport and physical activity is generally believed to be beneficial to young people's psychosocial health, but the scientific evidence seems equivocal. This article gives a narrative review of recent developments in the literature on psychosocial health effects of physical activity and sport among children and adolescents. Based on a narrative review of a selection of metaanalytical and key studies, results in four areas of psychosocial functioning are presented. Findings support an association between involvement in physical activity and sport and well-being. Physical activity is associated with lower levels of mental health problems, and seems to promote self-esteem. Physical activity as a treatment of mental health problems for this age group is underexplored and no firm conclusions can be made. The evidence with respect to effects on cognitive and academic functioning is weak. Further, the evidence that juvenile delinquency and antisocial development could be counteracted is equivocal. There is a paucity of studies that can confirm any causal effects. Future research would benefit particularly from studying the role of sports and physical activity mode as well as the psychological and social context in which it may produce beneficial psychosocial outcomes.

[Design of a conceptual model on the transference of public health research results in Honduras].

PubMed

Macías-Chapula, César A

2012-01-01

To design a conceptual model on the transference of public health research results at the local, context level. Using systems thinking concepts, a soft systems approach (SSM) was used to analyse and solve what was perceived as a problem situation related to the transference of research results within Honduras public health system. A bibliometric analysis was also conducted to enrich the problem situation. Six root definitions were defined and modeled as relevant to the expressed problem situation. This led to the development of the conceptual model. The model obtained identified four levels of resolution as derived from the human activities involved in the transference of research results: 1) those of the researchers; 2) the information/documentation professionals; 3) health staff; and 4) the population/society. These actors/ clients and their activities were essential to the functioning of the model since they represent what the model is and does. SSM helped to design the conceptual model. The bibliometric analysis was relevant to construct the rich image of the problem situation.

Test of Understanding of Vectors: A Reliable Multiple-Choice Vector Concept Test

ERIC Educational Resources Information Center

Barniol, Pablo; Zavala, Genaro

2014-01-01

In this article we discuss the findings of our research on students' understanding of vector concepts in problems without physical context. First, we develop a complete taxonomy of the most frequent errors made by university students when learning vector concepts. This study is based on the results of several test administrations of open-ended…

How Can "Weightless" Astronauts Be Weighed?

ERIC Educational Resources Information Center

Carnicer, Jesus; Reyes, Francisco; Guisasola, Jenaro

2012-01-01

In introductory physics courses, within the context of studying Newton's laws, it is common to consider the problem of a body's "weight" when it is in free fall. The solution shows that the "weight" is zero and this leads to a discussion of the concept of weight. There are permanent free-fall situations such as astronauts in a spacecraft orbiting…

Probing Student Reasoning Approaches through the Lens of Dual-Process Theories: A Case Study in Buoyancy

ERIC Educational Resources Information Center

Gette, Cody R.; Kryjevskaia, Mila; Stetzer, MacKenzie R.; Heron, Paula R. L.

2018-01-01

A growing body of scholarly work indicates that student performance on physics problems stems from many factors, including relevant conceptual understanding. However, in contexts in which significant conceptual difficulties have been documented via research, it can be difficult to pinpoint and isolate such factors because students' written and…

Have Sex Differences in Spatial Ability Evolved from Male Competition for Mating and Female Concern for Survival?

ERIC Educational Resources Information Center

Ecuyer-Dab, Isabelle; Robert, Michele

2004-01-01

Drawing on the theoretical and empirical foundations of two evolutionary models, we argue that, among humans and other mammals, a twofold selection process would parsimoniously account for sex-linked advantages in spatial contexts. In males, a superiority for both solving navigation-related spatial problems and understanding physical principles…

Learning about Flood Risk: Comparing the Web-Based and Physical Flood-Walk Learning Environments

ERIC Educational Resources Information Center

Chang Rundgren, Shu-Nu; Nyberg, Lars; Evers, Mariele; Alexandersson, Jan

2015-01-01

Numerous of sustainable development related challenges are emerging today, e.g. flooding problems. Our group has developed "the flood walk" project since 2010 to convey flood risk knowledge in an authentic context. Considering the limitation of time and space to educate people the flood risk knowledge, we tried to transform the physical…

Exploring the quantum speed limit with computer games.

PubMed

Sørensen, Jens Jakob W H; Pedersen, Mads Kock; Munch, Michael; Haikka, Pinja; Jensen, Jesper Halkjær; Planke, Tilo; Andreasen, Morten Ginnerup; Gajdacz, Miroslav; Mølmer, Klaus; Lieberoth, Andreas; Sherson, Jacob F

2016-04-14

Humans routinely solve problems of immense computational complexity by intuitively forming simple, low-dimensional heuristic strategies. Citizen science (or crowd sourcing) is a way of exploiting this ability by presenting scientific research problems to non-experts. 'Gamification'--the application of game elements in a non-game context--is an effective tool with which to enable citizen scientists to provide solutions to research problems. The citizen science games Foldit, EteRNA and EyeWire have been used successfully to study protein and RNA folding and neuron mapping, but so far gamification has not been applied to problems in quantum physics. Here we report on Quantum Moves, an online platform gamifying optimization problems in quantum physics. We show that human players are able to find solutions to difficult problems associated with the task of quantum computing. Players succeed where purely numerical optimization fails, and analyses of their solutions provide insights into the problem of optimization of a more profound and general nature. Using player strategies, we have thus developed a few-parameter heuristic optimization method that efficiently outperforms the most prominent established numerical methods. The numerical complexity associated with time-optimal solutions increases for shorter process durations. To understand this better, we produced a low-dimensional rendering of the optimization landscape. This rendering reveals why traditional optimization methods fail near the quantum speed limit (that is, the shortest process duration with perfect fidelity). Combined analyses of optimization landscapes and heuristic solution strategies may benefit wider classes of optimization problems in quantum physics and beyond.

More than just "plug-and-chug": Exploring how physics students make sense with equations

NASA Astrophysics Data System (ADS)

Kuo, Eric

Although a large part the Physics Education Research (PER) literature investigates students' conceptual understanding in physics, these investigations focus on qualitative, conceptual reasoning. Even in modeling expert problem solving, attention to conceptual understanding means a focus on initial qualitative analysis of the problem; the equations are typically conceived of as tools for "plug-and-chug" calculations. In this dissertation, I explore the ways that undergraduate physics students make conceptual sense of physics equations and the factors that support this type of reasoning through three separate studies. In the first study, I investigate how students' can understand physics equations intuitively through use of a particular class of cognitive elements, symbolic forms (Sherin, 2001). Additionally, I show how students leverage this intuitive, conceptual meaning of equations in problem solving. By doing so, these students avoid algorithmic manipulations, instead using a heuristic approach that leverages the equation in a conceptual argument. The second study asks the question why some students use symbolic forms and others don't. Although it is possible that students simply lack the knowledge required, I argue that this is not the only explanation. Rather, symbolic forms use is connected to particular epistemological stances, in-the-moment views on what kinds of knowledge and reasoning are appropriate in physics. Specifically, stances that value coherence between formal, mathematical knowledge and intuitive, conceptual knowledge are likely to support symbolic forms use. Through the case study of one student, I argue that both reasoning with equations and epistemological stances are dynamic, and that shifts in epistemological stance can produce shifts in whether symbolic forms are used to reason with equations. The third study expands the focus to what influences how students reason with equations across disciplinary problem contexts. In seeking to understand differences in how the same student reasons on two similar problems in calculus and physics, I show two factors, beyond the content or structure of the problems, that can help explain why reasoning on these two problems would be so different. This contributes to an understanding of what can support or impede transfer of content knowledge across disciplinary boundaries.

Time-lagged response of carabid species richness and composition to past management practices and landscape context of semi-natural field margins.

PubMed

Alignier, Audrey; Aviron, Stéphanie

2017-12-15

Field margins are key features for the maintenance of biodiversity and associated ecosystem services in agricultural landscapes. Little is known about the effects of management practices of old semi-natural field margins, and their historical dimension regarding past management practices and landscape context is rarely considered. In this paper, the relative influence of recent and past management practices and landscape context (during the last five years) were assessed on the local biodiversity (species richness and composition) of carabid assemblages of field margins in agricultural landscapes of northwestern France. The results showed that recent patterns of carabid species richness and composition were best explained by management practices and landscape context measured four or five years ago. It suggests the existence of a time lag in the response of carabid assemblages to past environmental conditions of field margins. The relative contribution of past management practices and past landscape context varied depending on the spatial scale at which landscape context was taken into account. Carabid species richness was higher in grazed or sprayed field margins probably due to increased heterogeneity in habitat conditions. Field margins surrounded by grasslands and crops harbored species associated with open habitats whilst forest species dominated field margins surrounded by woodland. Landscape effect was higher at fine spatial scale, within 50 m around field margins. The present study highlights the importance of considering time-lagged responses of biodiversity when managing environment. It also suggests that old semi-natural field margins should not be considered as undisturbed habitats but more as management units being part of farming activities in agricultural landscapes, as for arable fields. Copyright © 2017 Elsevier Ltd. All rights reserved.

Visual Activities for Assessing Non-science Majors’ Understanding in Introductory Astronomy

NASA Astrophysics Data System (ADS)

Loranz, Daniel; Prather, E. E.; Slater, T. F.

2006-12-01

One of the most ardent challenges for astronomy teachers is to deeply and meaningfully assess students’ conceptual and quantitative understanding of astronomy topics. In an effort to uncover students’ actual understanding, members and affiliates of the Conceptual Astronomy and Physics Education Research (CAPER) Team at the University of Arizona and Truckee Meadows Community College are creating and field-testing innovative approaches to assessment. Leveraging from the highly successful work on interactive lecture demonstrations from astronomy and physics education research, we are creating a series of conceptually rich questions that are matched to visually captivating and purposefully interactive astronomical animations. These conceptually challenging tasks are being created to span the entire domain of topics in introductory astronomy for non-science majoring undergraduates. When completed, these sorting tasks and vocabulary-in-context activities will be able to be delivered via a drag-and-drop computer interface.

Rich Experiences, Physical Activity Create Healthy Brains: An Interview with Developmental Psychologist William Greenough. Perspectives

ERIC Educational Resources Information Center

Ray, Marcy, Ed.

2006-01-01

In this interview, Council member William Greenough discusses the need for rich, complex experiences combined with physical activity in early childhood to help build a strong foundation for learning. He explains how rich, complex experiences are necessary for the development of sound brain architecture, particularly during early childhood, but…

Enhancing Practice through Clinically Rich Methods Courses in Physical Education: Perceptions of Preservice Teachers and Their Cooperating Teachers

ERIC Educational Resources Information Center

Flory, Sara Barnard; Burns, Rebecca West

2017-01-01

Similar to other teacher education disciplines, Physical Education Teacher Education (PETE) must adjust to calls for clinically rich teacher preparation because knowledge learned in PETE does not easily transfer to cultures of schools, classrooms, and gymnasia. Opportunity exists to understand more about clinically rich PETE courses, particularly…

[Violence against women in transnational communities in San Luis Potosí, Mexico: a public health problem].

PubMed

Flores, Yesica Yolanda Rangel

2016-08-01

Violence against women is a worldwide problem due to its impact on quality of life for those living under the complicity of a patriarchal culture and a state that makes such violence invisible. This article aims to give visibility to the contexts of violence affecting female "partners of migrants" in their places of origin, problematizing how such violence assaults their physical and mental health. This was a qualitative study with an interpretative anthropological focus, drawing on a sample of 21 women from rural and urban areas in San Luis Potosí, Mexico. Interviews were based on daily life history and discourse analysis. According to the results, women experience more violence when their spouses migrate, new forms of violence are committed against them, and the violence occurs in both the household and the community. Violence against women is a public health problem that should be treated through a framework that is sensitive to the social and cultural dynamics characterizing the contexts in which health programs are implemented.

Introducing a Framework for Physics Innovation and Entrepreneurship (PIE) Education

NASA Astrophysics Data System (ADS)

Roughani, Bahram

A desired outcome for Physics Innovation and Entrepreneurship (PIE) education is preparing physics majors with an innovative and entrepreneurial mindset who are capable of opportunity recognition and adept in leveraging physics knowledge to address specific needs. Physics as a discipline is well-recognized to prepare students who become problem solvers and critical thinkers, gifted in dealing with abstract ideas and ambiguities in the context of complex and real-world problems. These characteristics when enhanced through appropriate combinations of curricular, co-curricular, and extra-curricular programs can prepare physics majors for careers and future challenges that may involve translating physics knowledge into useful products and services either as part of a technical team within an organization or through startups. A viable PIE education model prepares graduates for various career paths in addition to the traditional options such as pursuing graduate studies or becoming a science teacher. Having a well-defined ``third option'' for physics will benefit the robustness of the physics discipline through recruitment and retention of prospective students who in principle are interested in physics as a subject, but in practice they may overlook physics as their preferred major primarily because they are uncertain about a viable career path based on an undergraduate physics education. The ''Pathways to Innovation'' at Loyola is established based on the program developed by VentureWell and Epicenter (NSF Supported).

Combining physical and virtual contexts through augmented reality: design and evaluation of a prototype using a drug box as a marker for antibiotic training

PubMed Central

Tomson, Tanja; Zary, Nabil

2014-01-01

Introduction. Antimicrobial resistance is a global health issue. Studies have shown that improved antibiotic prescription education among healthcare professionals reduces mistakes during the antibiotic prescription process. The aim of this study was to investigate novel educational approaches that through the use of Augmented Reality technology could make use of the real physical context and thereby enrich the educational process of antibiotics prescription. The objective is to investigate which type of information related to antibiotics could be used in an augmented reality application for antibiotics education. Methods. This study followed the Design-Based Research Methodology composed of the following main steps: problem analysis, investigation of information that should be visualized for the training session, and finally the involvement of the end users the development and evaluation processes of the prototype. Results. Two of the most important aspects in the antibiotic prescription process, to represent in an augmented reality application, are the antibiotic guidelines and the side effects. Moreover, this study showed how this information could be visualized from a mobile device using an Augmented Reality scanner and antibiotic drug boxes as markers. Discussion. In this study we investigated the usage of objects from a real physical context such as drug boxes and how they could be used as educational resources. The logical next steps are to examine how this approach of combining physical and virtual contexts through Augmented Reality applications could contribute to the improvement of competencies among healthcare professionals and its impact on the decrease of antibiotics resistance. PMID:25548733

Combining physical and virtual contexts through augmented reality: design and evaluation of a prototype using a drug box as a marker for antibiotic training.

PubMed

Nifakos, Sokratis; Tomson, Tanja; Zary, Nabil

2014-01-01

Introduction. Antimicrobial resistance is a global health issue. Studies have shown that improved antibiotic prescription education among healthcare professionals reduces mistakes during the antibiotic prescription process. The aim of this study was to investigate novel educational approaches that through the use of Augmented Reality technology could make use of the real physical context and thereby enrich the educational process of antibiotics prescription. The objective is to investigate which type of information related to antibiotics could be used in an augmented reality application for antibiotics education. Methods. This study followed the Design-Based Research Methodology composed of the following main steps: problem analysis, investigation of information that should be visualized for the training session, and finally the involvement of the end users the development and evaluation processes of the prototype. Results. Two of the most important aspects in the antibiotic prescription process, to represent in an augmented reality application, are the antibiotic guidelines and the side effects. Moreover, this study showed how this information could be visualized from a mobile device using an Augmented Reality scanner and antibiotic drug boxes as markers. Discussion. In this study we investigated the usage of objects from a real physical context such as drug boxes and how they could be used as educational resources. The logical next steps are to examine how this approach of combining physical and virtual contexts through Augmented Reality applications could contribute to the improvement of competencies among healthcare professionals and its impact on the decrease of antibiotics resistance.

Measuring self-regulation in a physically active context: Psychometric analyses of scores derived from an observer-rated measure of self-regulation.

PubMed

Lakes, Kimberley D

2013-10-01

The purpose of this study is to report psychometric properties of scores obtained using a novel observer-rated measure of children's self-regulation, the Response to Challenge Scale (RCS). The RCS was developed to rate children's self-regulatory abilities in a physically active context (e.g., while completing a physical challenge course). The RCS and other study measures were administered in a private school sample of 207 children. Analyses of score distributions indicated that the RCS was able to capture variance among children in self-regulatory abilities; the distribution was normal for the Affective, Cognitive, and Total Self-Regulation scales. Validity analyses revealed significant positive correlations between Cognitive, Affective, Motor, and Total Self-Regulation and executive function task performance; significant negative correlations between Cognitive Regulation and teacher-rated hyperactivity and inattention; significant negative correlations between Affective, Motor, and Total Self-Regulation and teacher ratings of peer problems; and significant positive correlations between Cognitive and Affective Regulation and parent ratings of prosocial behavior. Parent and teacher rated Total Difficulties scores were both negatively correlated with RCS Total Self-Regulation scores. Results suggest that it is possible for observers to rate self-regulatory abilities in the context of physical activities, and that these ratings correspond with performance on tasks requiring executive function as well as teacher and parent ratings of children's difficulties.

Autotransfusion in cardiac surgery.

PubMed

Cross, M H

2001-09-01

There are a number of problems with allogeneic blood transfusion. Some of these problems are defined and can be quantified, such as the problem of rising cost or the risk of viral infection, but some of the problems are not well defined and it is only outcome data that point to allogeneic blood transfusion contributing to patient mortality and morbidity. Autotransfusion includes any technique in which the patient's own blood is collected, processed and stored, followed by reinfusion when circumstances dictate. In the perioperative period of cardiac surgery, a number of techniques are recognized as useful in this context. Preoperative autologous donation, with or without erythropoietin supplementation, intraoperative acute normovolaemic haemodilution, intraoperative cell salvage, postoperative cell salvage (reinfusion of shed mediastinal blood) and platelet rich plasmapheresis are all techniques which are used with more or less enthusiasm to reduce the need for an allogeneic blood transfusion. Modification of the priming technique of the cardiopulmonary bypass circuit using an autologous blood prime is included in this review even though it does not fall strictly within the definition of autotransfusion. Although autotransfusion is not the answer to every problem, there is no doubt that it should play a significant part in the strategy of blood conservation.

Features versus context: An approach for precise and detailed detection and delineation of faces and facial features.

PubMed

Ding, Liya; Martinez, Aleix M

2010-11-01

The appearance-based approach to face detection has seen great advances in the last several years. In this approach, we learn the image statistics describing the texture pattern (appearance) of the object class we want to detect, e.g., the face. However, this approach has had limited success in providing an accurate and detailed description of the internal facial features, i.e., eyes, brows, nose, and mouth. In general, this is due to the limited information carried by the learned statistical model. While the face template is relatively rich in texture, facial features (e.g., eyes, nose, and mouth) do not carry enough discriminative information to tell them apart from all possible background images. We resolve this problem by adding the context information of each facial feature in the design of the statistical model. In the proposed approach, the context information defines the image statistics most correlated with the surroundings of each facial component. This means that when we search for a face or facial feature, we look for those locations which most resemble the feature yet are most dissimilar to its context. This dissimilarity with the context features forces the detector to gravitate toward an accurate estimate of the position of the facial feature. Learning to discriminate between feature and context templates is difficult, however, because the context and the texture of the facial features vary widely under changing expression, pose, and illumination, and may even resemble one another. We address this problem with the use of subclass divisions. We derive two algorithms to automatically divide the training samples of each facial feature into a set of subclasses, each representing a distinct construction of the same facial component (e.g., closed versus open eyes) or its context (e.g., different hairstyles). The first algorithm is based on a discriminant analysis formulation. The second algorithm is an extension of the AdaBoost approach. We provide extensive experimental results using still images and video sequences for a total of 3,930 images. We show that the results are almost as good as those obtained with manual detection.

Contextual Richness and Word Learning: Context Enhances Comprehension but Retrieval Enhances Retention

ERIC Educational Resources Information Center

van den Broek, Gesa S. E.; Takashima, Atsuko; Segers, Eliane; Verhoeven, Ludo

2018-01-01

Learning new vocabulary from context typically requires multiple encounters during which word meaning can be retrieved from memory or inferred from context. We compared the effect of memory retrieval and context inferences on short- and long-term retention in three experiments. Participants studied novel words and then practiced the words either…

Automatic Identification of Nutritious Contexts for Learning Vocabulary Words

ERIC Educational Resources Information Center

Mostow, Jack; Gates, Donna; Ellison, Ross; Goutam, Rahul

2015-01-01

Vocabulary knowledge is crucial to literacy development and academic success. Previous research has shown learning the meaning of a word requires encountering it in diverse informative contexts. In this work, we try to identify "nutritious" contexts for a word--contexts that help students build a rich mental representation of the word's…

Medical Settings as a Context for Research on Cognitive Development

ERIC Educational Resources Information Center

Salmon, Karen; Brown, Deirdre A.

2013-01-01

Medical contexts provide a rich opportunity to study important theoretical questions in cognitive development and to investigate the influence of a range of interacting factors relating to the child, the experience, and the broader social context on children's cognition. In the context of examples of research investigating these issues, we…

Relationship among fish assemblages and main-channel-border physical habitats in the unimpounded Upper Mississippi River

USGS Publications Warehouse

Barko, V.A.; Herzog, D.P.; Hrabik, R.A.; Scheibe, J.S.

2004-01-01

Large rivers worldwide have been altered by the construction and maintenance of navigation channels, which include extensive bank revetments, wing dikes, and levees. Using 7 years of Long-Term Resource Monitoring Program (LTRMP) data collected from the unimpounded upper Mississippi River, we investigated assemblages in two main-channel-border physical habitats-those with wing dikes and those without wing dikes. Fishes were captured using daytime electrofishing, mini-fyke netting, large hoop netting, and small hoop netting. Our objectives were to (1) assess associations among fish species richness, physical measurements, and main-channel-border physical habitats using stepwise multiple regression and indicator variables; (2) identify abundant adult and young-of-year (age-0) families in both physical habitats to further investigate assemblage composition; and (3) calculate standardized species richness estimates within each physical habitat for adult and age-0 fishes to provide additional information on community structure. We found species richness was greater at wing dikes for both adult and age-0 fishes when compared with main channel borders. Stepwise multiple regression revealed significant relationships between adult species richness and passive gear deployment (e.g,, hoop nets and mini-fyke nets), physical habitat type, and river elevation, as well as interactions between physical habitat and passive gears, and physical habitat and transparency (i.e., Secchi depth). This model explained 56% of the variance in adult species richness. Approximately 15% of the variation in age-0 species richness was explained by the sample period, sample date, transparency, physical habitat, and depth of gear deployment. Long-term impacts of river modifications on fishes have not been well documented in many large river systems and warrant further study. The findings from this study provide baseline ecological information on fish assemblages using main channel borders in the unimpounded upper Mississippi River, information that will aid managers making channel maintenance decisions in large river systems.

New ligand platforms featuring boron-rich clusters as organomimetic substituents*,**

PubMed Central

Spokoyny, Alexander M.

2013-01-01

200 years of research with carbon-rich molecules have shaped the development of modern chemistry. Research pertaining to the chemistry of boron-rich species has historically trailed behind its more distinguished neighbor (carbon) in the periodic table. Notably, a potentially rich and, in many cases, unmatched field of coordination chemistry using boronrich clusters remains fundamentally underdeveloped. Our work has been devoted to examining several basic concepts related to the functionalization of icosahedral boron-rich clusters and their use as ligands, aimed at designing fundamentally new hybrid molecular motifs and materials. Particularly interesting are icosahedral carboranes, which can be regarded as 3D analogs of benzene. These species comprise a class of boron-rich clusters that were discovered in the 1950s during the “space race” while researchers were developing energetic materials for rocket fuels. Ultimately, the unique chemical and physical properties of carborane species, such as rigidity, indefinite stability to air and moisture, and 3D aromaticity, may allow one to access a set of properties not normally available in carbon-based chemistry. While technically these species are considered as inorganic clusters, the chemical properties they possess make these boron-rich species suitable for replacing and/or altering structural and functional features of the organic and organometallic molecules—a phenomenon best described as “organomimetic”. Aside from purely fundamental features associated with the organomimetic chemistry of icosahedral carboranes, their use can also provide new avenues in the development of systems relevant to solving current problems associated with energy production, storage, and conversion. PMID:24311823

Elaboration of the Environmental Stress Hypothesis–Results from a Population-Based 6-Year Follow-Up

PubMed Central

Wagner, Matthias; Jekauc, Darko; Worth, Annette; Woll, Alexander

2016-01-01

The aim of this paper was to contribute to the elaboration of the Environmental Stress Hypothesis framework by testing eight hypotheses addressing the direct impact of gross motor coordination problems in elementary-school on selected physical, behavioral and psychosocial outcomes in adolescence. Results are based on a longitudinal sample of 940 participants who were (i) recruited as part of a population-based representative survey on health, physical fitness and physical activity in childhood and adolescence, (ii) assessed twice within 6 years, between the ages of 6 and 10 years old as well as between the ages of 12 and 16 years old (Response Rate: 55.9%) and (iii) classified as having gross motor coordination problems (N = 115) or having no gross motor coordination problems (N = 825) at baseline. Motor tests from the Körperkoordinationstest, measures of weight and height, a validated physical activity questionnaire as well as the Strength and Difficulties Questionnaire were conducted. Data were analyzed by use of binary logistic regressions. Results indicated that elementary-school children with gross motor coordination problems show a higher risk of persistent gross motor coordination problems (OR = 7.99, p < 0.001), avoiding organized physical activities (OR = 1.53, p < 0.05), an elevated body mass (OR = 1.78, p < 0.05), bonding with sedentary peers (OR = 1.84, p < 0.01) as well as emotional (OR = 1.73, p < 0.05) and conduct (OR = 1.79, p < 0.05) problems in adolescence in comparison to elementary-school children without gross motor coordination problems. However, elementary-school children with gross motor coordination problems did not show a significantly higher risk of peer problems (OR = 1.35, p = 0.164) or diminished prosocial behavior (OR = 1.90, p = 0.168) in adolescence, respectively in comparison to elementary-school children without gross motor coordination problems. This study is the first to provide population-based longitudinal data ranging from childhood to adolescence in the context of the Environmental Stress Hypothesis which can be considered a substantial methodological progress. In summary, gross motor coordination problems represent a serious issue for a healthy transition from childhood to adolescence which substantiates respective early movement interventions. PMID:28018254

The Anatomy of a Pitch: Doing Physics with PITCHf/x Data

NASA Astrophysics Data System (ADS)

Kagan, David

2009-10-01

On Aug. 7, 2007, Barry Bonds of the San Francisco Giants was at bat waiting for a 3-2 pitch from Mike Bacsik of the Washington Nationals. The ball left the pitcher's hand at 84.7 mph and arrived at home plate traveling 77.2 mph. It was within 0.2 in of the center of home plate and 3.213 ft above the ground when Bonds swung and hit his 756th home run, making him the all-time leader for homers in a career. Thanks to a company called Sportvision and Major League Baseball, you can get kinematic data on any pitch thrown. Just think of the interesting and realistic physics problems you can generate from such a rich data set!

Time use differences in activity participation among children 4-5 years old with and without the risk of developing conduct problems.

PubMed

Yu, Mong-Lin; Ziviani, Jenny; Baxter, Janeen; Haynes, Michele

2012-01-01

Conduct problems in childhood are associated with the way in which children engage in daily activities. Research, to date, on conduct problems in relation to time use has primarily focused on school aged children and their participation in discrete activities such as watching TV and sport. The purpose of the present study is to determine if children at risk of developing conduct problems have different activity patterns compared to those not at risk. Specifically aspects of time use which concern involvement in activities that provide physical exertion, structure, rest and social engagement were examined. Data for this investigation were drawn from the Longitudinal Study of Australian Children (Wave 1) and focused on 4936 children aged 4-5 years. Findings indicate that children at risk of developing conduct problems spend significantly more time in: physical activities such as "riding a bike", and "in the company of adults only" than children not at risk of developing conduct problems but less time "with peers under adult supervision". Gender differences were also found in the same activities with boys participating in more "bike riding" and activities "without peers under adult supervision" than girls. Young children generally participated in more physical activities and spend more time "with peers while supervised by adults" on weekend days, and more time in "structured activities" and "in the company of adults only" on weekdays. These findings are discussed in respect of the potentially risky nature of physical activity choice and the contribution of adult supervision in the context of peer group participation for children at risk of developing conduct problems. Copyright © 2011 Elsevier Ltd. All rights reserved.

Exposure to air pollution and self-reported effects on Chinese students: A case study of 13 megacities.

PubMed

Rajper, Sohail Ahmed; Ullah, Sana; Li, Zhongqiu

2018-01-01

Air pollution causes severe physical and psychological health complications. Considering China's continuously-deteriorating air quality, this study aimed to assess the self-reported effects of air pollution on the behavior and physical health of the students of 13 densely populated cities, and their awareness, practices, and perception of air pollution and its associated public health risks. A detailed, closed-ended questionnaire was administered to 2100 students from 54 universities and schools across China. The questionnaire, which had 24 questions, was categorized into four sections. The first two sections were focused on air pollution-associated behavior and psychology, and physical effects; while the final two sections focused on the subjects' awareness and perceptions, and practices and concerns about air pollution. The respondents reported that long-term exposure to air pollution had significantly affected their psychology and behavior, as well as their physical health. The respondents were aware of the different adverse impacts of air pollution (respiratory infections, allergies, and cardiovascular problems), and hence had adopted different preventive measures, such as the use of respiratory masks and glasses or goggles, regularly drinking water, and consuming rich foods. It was concluded that air pollution and haze had negative physical and psychological effects on the respondents, which led to severe changes in behavior. Proper management, future planning, and implementing strict environmental laws are suggested before this problem worsens and becomes life-threatening.

Atomistic Model of Physical Ageing in Se-rich As-Se Glasses

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

Golovchak,R.; Shpotyuk, O.; Kozdras, A.

2007-01-01

Thermal, optical, X-ray excited and magnetic methods were used to develop a microstructural model of physical ageing in Se-rich glasses. The glass composition As10Se90, possessing a typical cross-linked chain structure, was chosen as a model object for the investigations. The effect of physical ageing in this glass was revealed by differential scanning calorimetry, whereas the corresponding changes in its atomic arrangement were studied by extended X-ray absorption fine structure, Raman and solid-state 77Se nuclear magnetic resonance spectroscopy. Straightening-shrinkage processes are shown to be responsible for the physical ageing in this Se-rich As-Se glass.

Design Steps for Physic STEM Education Learning in Secondary School

NASA Astrophysics Data System (ADS)

Teevasuthonsakul, C.; Yuvanatheeme, V.; Sriput, V.; Suwandecha, S.

2017-09-01

This study aimed to develop the process of STEM Education activity design used in Physics subjects in the Thai secondary schools. The researchers have conducted the study by reviewing the literature and related works, interviewing Physics experts, designing and revising the process accordingly, and experimenting the designed process in actual classrooms. This brought about the five-step process of STEM Education activity design which Physics teachers applied to their actual teaching context. The results from the after-class evaluation revealed that the students’ satisfaction level toward Physics subject and critical thinking skill was found higher statistically significant at p < .05. Moreover, teachers were advised to integrate the principles of science, mathematics, technology, and engineering design process as the foundation when creating case study of problems and solutions.

Mapping Social Ecological Systems Archetypes

NASA Astrophysics Data System (ADS)

Rocha, J. C.; Malmborg, K.; Gordon, L.

2016-12-01

Achieving sustainable development goals requires targeting and monitoring sustainable solutions tailored to different social and ecological contexts. Elinor Ostrom stressed that there is no panaceas or universal solutions to environmental problems, and developed a social-ecological systems' (SES) framework -a nested multi tier set of variables- to help diagnose problems, identify complex interactions, and solutions tailored to each SES arena. However, to our knowledge, the SES framework has only been applied to over a hundred cases, and typically reflect the analysis of local case studies with relatively small coverage in space and time. While case studies are context rich and necessary, their conclusions might not reach policy making instances. Here we develop a data driven method for upscaling Ostrom's SES framework and applied to a context where we expect data is scarce, incomplete, but also where sustainable solutions are badly needed. The purpose of upscaling the framework is to create a tool that facilitates decision making on data scarce environments such as developing countries. We mapped SES by applying the SES framework to poverty alleviation and food security issues in the Volta River basin in Ghana and Burkina Faso. We found archetypical configurations of SES in space given data availability, we study their change over time, and discuss where agricultural innovations such as water reservoirs might have a stronger impact at increasing food security and therefore alleviating poverty and hunger. We conclude outlining how the method can be used in other SES comparative studies.

Time-dependent interstellar chemistry

NASA Technical Reports Server (NTRS)

Glassgold, A. E.

1985-01-01

Some current problems in interstellar chemistry are considered in the context of time-dependent calculations. The limitations of steady-state models of interstellar gas-phase chemistry are discussed, and attempts to chemically date interstellar clouds are reviewed. The importance of studying the physical and chemical properties of interstellar dust is emphasized. Finally, the results of a series of studies of collapsing clouds are described.

The Effect of Friction in Pulleys on the Tension in Cables and Strings

ERIC Educational Resources Information Center

Martell, Eric C.; Martell, Verda Beth

2013-01-01

Atwood's machine is used in countless introductory physics classes as an illustration of Newton's second law. Initially, the analysis is performed assuming the pulley and string are massless and the axle is frictionless. Although the mass of the pulley is often included when the problem is revisited later in the context of rotational dynamics, the…

Learning with Multiple Representations: An Example of a Revision Lesson in Mathematics

ERIC Educational Resources Information Center

Wong, Darren; Poo, Sng Peng; Hock, Ng Eng; Kang, Wee Loo

2011-01-01

We describe an example of learning with multiple representations in an A-level revision lesson on mechanics. The context of the problem involved the motion of a ball thrown vertically upwards in air and studying how the associated physical quantities changed during its flight. Different groups of students were assigned to look at the ball's motion…

Taking the hit: focusing on caregiver "error" masks organizational-level risk factors for nursing aide assault.

PubMed

Morgan, Debra G; Crossley, Margaret F; Stewart, Norma J; D'Arcy, Carl; Forbes, Dorothy A; Normand, Sandy A; Cammer, Allison L

2008-03-01

Beliefs about the causes of events have implications for emotional reactions, distress, expectations for the future, and behavioral responses. In this article we report on two issues: the organizational context that contributes to nursing aide (NA) assault and reporting, and serendipitous findings that arose from investigating unexpected response rates to a survey. Data were collected in 11 rural nursing homes using a structured prospective event-reporting diary to collect detailed information about incidents of physical aggression, followed by focus groups to further explore NAs' perceptions of these events. Here we report on analysis of 19 focus groups conducted with 138 NAs. Participants described organizational-level factors that constrained their practice, affected their interactions with residents, and created a context that put them at risk for physical assault. These factors also affected their willingness to provide written documentation about aggressive incidents. The key issues were frustration at being blamed for causing aggression, lack of action to address the problem, and a desire for respect and involvement in decision making. Organizational changes are needed to modify the contextual factors contributing to assault risk. Researchers must be willing to modify study designs to more fully understand the nature of the problem studied.

Leveraging Cognitive Context for Object Recognition

DTIC Science & Technology

2014-06-01

learned from large image databases. We build upon this concept by exploring cognitive context, demonstrating how rich dynamic context provided by...context that people rely upon as they perceive the world. Context in ACT-R/E takes the form of associations between related concepts that are learned ...and accuracy of object recognition. Context is most often viewed as a static concept, learned from large image databases. We build upon this concept by

Collaboration, Communication and Co-ordination in Agile Software Development Practice

NASA Astrophysics Data System (ADS)

Robinson, Hugh; Sharp, Helen

This chapter analyses the results of a series of observational studies of agile software developmentagile software development teams, identifying commonalities in collaboration, co-ordination and communication activities. Pairing and customer collaborationcustomer collaboration are focussed on to illustrate the nature of collaboration and communication, as are two simple physical artefacts that emerged through analysis as being an information-rich focal point for the co-ordination of collaboration and communication activities. The analysis shows that pairingpairing has common characteristics across all teams, while customer collaboration differs between the teams depending on the application and organisational context of development.

Toward a virtual building laboratory

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

Klems, J.H.; Finlayson, E.U.; Olsen, T.H.

1999-03-01

In order to achieve in a timely manner the large energy and dollar savings technically possible through improvements in building energy efficiency, it will be necessary to solve the problem of design failure risk. The most economical method of doing this would be to learn to calculate building performance with sufficient detail, accuracy and reliability to avoid design failure. Existing building simulation models (BSM) are a large step in this direction, but are still not capable of this level of modeling. Developments in computational fluid dynamics (CFD) techniques now allow one to construct a road map from present BSM's tomore » a complete building physical model. The most useful first step is a building interior model (BIM) that would allow prediction of local conditions affecting occupant health and comfort. To provide reliable prediction a BIM must incorporate the correct physical boundary conditions on a building interior. Doing so raises a number of specific technical problems and research questions. The solution of these within a context useful for building research and design is not likely to result from other research on CFD, which is directed toward the solution of different types of problems. A six-step plan for incorporating the correct boundary conditions within the context of the model problem of a large atrium has been outlined. A promising strategy for constructing a BIM is the overset grid technique for representing a building space in a CFD calculation. This technique promises to adapt well to building design and allows a step-by-step approach. A state-of-the-art CFD computer code using this technique has been adapted to the problem and can form the departure point for this research.« less

Teaching at the edge of knowledge: Non-equilibrium statistical physics

NASA Astrophysics Data System (ADS)

Schmittmann, Beate

2007-03-01

As physicists become increasingly interested in biological problems, we frequently find ourselves confronted with complex open systems, involving many interacting constituents and characterized by non-vanishing fluxes of mass or energy. Faced with the task of predicting macroscopic behaviors from microscopic information for these non-equilibrium systems, the familiar Gibbs-Boltzmann framework fails. The development of a comprehensive theoretical characterization of non-equilibrium behavior is one of the key challenges of modern condensed matter physics. In its absence, several approaches have been developed, from master equations to thermostatted molecular dynamics, which provide key insights into the rich and often surprising phenomenology of systems far from equilibrium. In my talk, I will address some of these methods, selecting those that are most relevant for a broad range of interdisciplinary problems from biology to traffic, finance, and sociology. The ``portability'' of these methods makes them valuable for graduate students from a variety of disciplines. To illustrate how different methods can complement each other when probing a problem from, e.g., the life sciences, I will discuss some recent attempts at modeling translation, i.e., the process by which the genetic information encoded on an mRNA is translated into the corresponding protein.

Caring in context: caring practices in a sample of Hong Kong nurses.

PubMed

Arthur, D; Pang, S; Wong, T

1998-12-01

In an effort to place the international literature and research in nursing in a Chinese cultural context a study was commenced to examine the caring practices of nurses in Hong Kong. In view of a recent study (Wilkes & Wallis, 1993) which utilised Roach's 5Cs of caring (Roach, 1987, 1992), a pilot study was commenced on a sample of 77 Hong Kong Registered Nurses studying a Diploma of Nursing. An open ended questionnaire was designed which asked nurses to respond to questions about caring in general and the 5Cs: compassion, competence, confidence, conscience and commitment. The questions asked what each of the concepts meant to them as a nurse. Data was analysed into themes based on key words for each of the six areas revealing that the sample of Hong Kong nurses viewed caring in a similar light to those in overseas studies. The sample highlighted compassion and competence as their major features and it is suggested that methodological problems may have inhibited a deeper analysis of their caring attributes and behaviours. When asked to expand on the 5 Cs in terms of their own practice they were able to supply themes which were closely related to Roach's definitions but which may have been more 'textbook' in their origin and certainly lacked a richness of response. The paucity of responses in terms of clarity and richness of data, followed by discussions with the participants led to conclusions about the methodological issues of cross-cultural research and recommendations for future research are made. Highlighted are the problems with attempting to use concepts such as the 5 Cs across cultures and the problems encountered with translation of concepts related to caring from Chinese into English, and vice-versa. The study has provided some insights into the concepts of caring in Hong Kong Chinese nurses. In the light of advances in China and unification of previously separate countries these findings provide and offer insights into nursing in China and are encouraging for future research.

Supporting Collective Inquiry: A Technology Framework for Distributed Learning

NASA Astrophysics Data System (ADS)

Tissenbaum, Michael

This design-based study describes the implementation and evaluation of a technology framework to support smart classrooms and Distributed Technology Enhanced Learning (DTEL) called SAIL Smart Space (S3). S3 is an open-source technology framework designed to support students engaged in inquiry investigations as a knowledge community. To evaluate the effectiveness of S3 as a generalizable technology framework, a curriculum named PLACE (Physics Learning Across Contexts and Environments) was developed to support two grade-11 physics classes (n = 22; n = 23) engaged in a multi-context inquiry curriculum based on the Knowledge Community and Inquiry (KCI) pedagogical model. This dissertation outlines three initial design studies that established a set of design principles for DTEL curricula, and related technology infrastructures. These principles guided the development of PLACE, a twelve-week inquiry curriculum in which students drew upon their community-generated knowledge base as a source of evidence for solving ill-structured physics problems based on the physics of Hollywood movies. During the culminating smart classroom activity, the S3 framework played a central role in orchestrating student activities, including managing the flow of materials and students using real-time data mining and intelligent agents that responded to emergent class patterns. S3 supported students' construction of knowledge through the use individual, collective and collaborative scripts and technologies, including tablets and interactive large-format displays. Aggregate and real-time ambient visualizations helped the teacher act as a wondering facilitator, supporting students in their inquiry where needed. A teacher orchestration tablet gave the teacher some control over the flow of the scripted activities, and alerted him to critical moments for intervention. Analysis focuses on S3's effectiveness in supporting students' inquiry across multiple learning contexts and scales of time, and in making timely and effective use of the community's knowledge base, towards producing solutions to sophisticated, ill defined problems in the domain of physics. Video analysis examined whether S3 supported teacher orchestration, freeing him to focus less on classroom management and more on students' inquiry. Three important outcomes of this research are a set of design principles for DTEL environments, a specific technology infrastructure (S3), and a DTEL research framework.

Who is the competent physics student? A study of students' positions and social interaction in small-group discussions

NASA Astrophysics Data System (ADS)

Due, Karin

2014-06-01

This article describes a study which explored the social interaction and the reproduction and challenge of gendered discourses in small group discussions in physics. Data for the study consisted of video recordings of eight upper secondary school groups solving physics problems and 15 audiotaped individual interviews with participating students. The analysis was based on gender theory viewing gender both as a process and a discourse. Specifically discursive psychology analysis was used to examine how students position themselves and their peers within discourses of physics and gender. The results of the study reveal how images of physics and of "skilled physics student" were constructed in the context of the interviews. These discourses were reconstructed in the students' discussions and their social interactions within groups. Traditional gendered positions were reconstructed, for example with boys positioned as more competent in physics than girls. These positions were however also resisted and challenged.

Analysis of wireless sensor network topology and estimation of optimal network deployment by deterministic radio channel characterization.

PubMed

Aguirre, Erik; Lopez-Iturri, Peio; Azpilicueta, Leire; Astrain, José Javier; Villadangos, Jesús; Falcone, Francisco

2015-02-05

One of the main challenges in the implementation and design of context-aware scenarios is the adequate deployment strategy for Wireless Sensor Networks (WSNs), mainly due to the strong dependence of the radiofrequency physical layer with the surrounding media, which can lead to non-optimal network designs. In this work, radioplanning analysis for WSN deployment is proposed by employing a deterministic 3D ray launching technique in order to provide insight into complex wireless channel behavior in context-aware indoor scenarios. The proposed radioplanning procedure is validated with a testbed implemented with a Mobile Ad Hoc Network WSN following a chain configuration, enabling the analysis and assessment of a rich variety of parameters, such as received signal level, signal quality and estimation of power consumption. The adoption of deterministic radio channel techniques allows the design and further deployment of WSNs in heterogeneous wireless scenarios with optimized behavior in terms of coverage, capacity, quality of service and energy consumption.

Drawing Connections Between Local and Global Observations: An Essential Element of Geoscience Education

NASA Astrophysics Data System (ADS)

Manduca, C. A.; Mogk, D. W.

2002-12-01

One of the hallmarks of geoscience research is the process of moving between observations and interpretations on local and global scales to develop an integrated understanding of Earth processes. Understanding this interplay is an important aspect of student geoscience learning which leads to an understanding of the fundamental principles of science and geoscience and of the connections between local natural phenomena or human activity and global processes. Several techniques that engage students in inquiry and discovery (as recommended in the National Science Education Standards, NRC 1996, Shaping the Future of Undergraduate Earth Science Education, AGU, 1997) hold promise for helping students make these connections. These include the development of global data sets from local observations (e.g. GLOBE); studying small scale or local phenomenon in the context of global models (e.g. carbon storage in local vegetation and its role in the carbon cycle); or an analysis of local environmental issues in a global context (e.g. a comparison of local flooding to flooding in other countries and analysis in the context of weather, geology and development patterns). Research on learning suggests that data-rich activities linking the local and global have excellent potential for enhancing student learning because 1) students have already developed observations and interpretations of their local environment which can serve as a starting point for constructing new knowledge and 2) this context may motivate learning and develop understanding that can be transferred to other situations. (How People Learn, NRC, 2001). Faculty and teachers at two recent workshops confirm that projects that involve local or global data can engage students in learning by providing real world context, creating student ownership of the learning process, and developing scientific skills applicable to the complex problems that characterize modern science and society. Workshop participants called for increased dissemination of examples of effective practice, evaluation of the impact of data-rich activities on learning, and further development of data access infrastructure and services. (for additional workshop results and discussion see http://serc.carleton.edu/research_education/usingdata)

A Natural Extension of Standard Warped Higher-Dimensional Compactifications: Theory and Phenomenology

NASA Astrophysics Data System (ADS)

Hong, Sungwoo

Warped higher-dimensional compactifications with "bulk'' standard model, or their AdS/CFT dual as the purely 4D scenario of Higgs compositeness and partial compositeness, offer an elegant approach to resolving the electroweak hierarchy problem as well as the origins of flavor structure. However, low-energy electroweak/flavor/CP constraints and the absence of non-standard physics at LHC Run 1 suggest that a "little hierarchy problem'' remains, and that the new physics underlying naturalness may lie out of LHC reach. Assuming this to be the case, we show that there is a simple and natural extension of the minimal warped model in the Randall-Sundrum framework, in which matter, gauge and gravitational fields propagate modestly different degrees into the IR of the warped dimension, resulting in rich and striking consequences for the LHC (and beyond). The LHC-accessible part of the new physics is AdS/CFT dual to the mechanism of "vectorlike confinement'', with TeV-scale Kaluza-Klein excitations of the gauge and gravitational fields dual to spin-0,1,2 composites. Unlike the minimal warped model, these low-lying excitations have predominantly flavor-blind and flavor/CP-safe interactions with the standard model. In addition, the usual leading decay modes of the lightest KK gauge bosons into top and Higgs bosons are suppressed. This effect permits erstwhile subdominant channels to become significant. These include flavor-universal decays to all pairs of SM fermions, and a novel channel--decay to a radion and a SM gauge boson, followed by radion decay to a pair of SM gauge bosons. We present a detailed phenomenological study of the latter cascade decay processes. Remarkably, this scenario also predicts small deviations from flavor-blindness originating from virtual effects of Higgs/top compositeness at O(10) TeV, with subdominant resonance decays into a pair of Higgs/top-rich final states, giving the LHC an early "preview'' of the nature of the resolution of the hierarchy problem. Discoveries of this type at LHC Run 2 would thereby anticipate (and set a target for) even more explicit explorations of Higgs compositeness at a 100 TeV collider, or for next-generation flavor tests.

Physics of the gut: How polymers dynamically structure the gut environment

NASA Astrophysics Data System (ADS)

Preska Steinberg, Asher; Datta, Sujit; Bogatyrev, Said; Ismagilov, Rustem

While the gut microbiome and biological regulation of the gut environment is being exhaustively studied by the microbiology community, little is known about the rich physics that governs the macro- and microstructure of the gut environment. The mammalian gut abounds in soft materials; ranging from soluble polymers (e.g. dietary fibers, therapeutic polymers and mucins) to colloidal matter (e.g. bacteria, viruses and nanoparticles carrying drugs). We have found experimentally that soluble polymers can dynamically re-structure the colonic mucus hydrogel by modulating its degree of swelling. We implemented a mean-field Flory-Huggins model to reveal that these polymer-mucus interactions can be captured using a simple, first principles thermodynamics model. In this model, the amount of deswelling increases with polymer concentration and size. We then used these physical principles to make predictions about how different polymer solutions affect the structure of mucus. Lastly, we explore applying this framework and similar physical principles to a variety of biological problems in the gut.

Physics moves to the provinces: the Siberian physics community and Soviet power, 1917-1940.

PubMed

Josephson, Paul; Sorokin, Aleksandr

2017-06-01

The rich tradition of Siberian science and higher education is little known outside Russian academic circles. Using institutional history, this article focuses on the founding and pre-war period of the Siberian Physical Technical Institute, the establishment of its research focus and its first difficult steps to become a leading centre of R & D in Siberia. Based on archival materials, the article describes how local and national physicists justified the institute's creation by demonstrating ties with industry and building on the presence of a cohort of locally trained physicists, whose numbers were augmented by Leningrad specialists. The strength of local cadres enabled the institute to navigate civil war and cultural revolution successfully. Physicists were able to take advantage of ongoing industrialization campaigns to gain support to create the institute, although local disputes and economic problems slowed its further development. The article describes the circulation of scientific, political and philosophical knowledge between Moscow, Leningrad and the provinces, and the impact of Bolshevik rule and Stalinism on the Siberian physics enterprise.

Measuring physical activity in children and adolescents for dietary surveys: practicalities, problems and pitfalls.

PubMed

Mindell, Jennifer S; Coombs, Ngaire; Stamatakis, Emmanuel

2014-05-01

Physical inactivity is an important risk factor for many chronic diseases and contributes to obesity and poor mental well-being. The present paper describes the main advantages and disadvantages, practical problems, suggested uses, and future developments regarding self-reported and objective data collection in the context of dietary surveys. In dietary surveys, physical activity is measured primarily to estimate energy expenditure. Energy expenditure surveillance is important for tracking changes over time, particularly given the debates over the role of the relative importance of energy intake and expenditure changes in the aetiology of obesity. It is also important to assess the extent of underreporting of dietary intake in these surveys. Physical activity data collected should include details on the frequency, duration and relative intensity of activity for each activity type that contributes considerably to overall activity and energy expenditure. Problems of validity and reliability, associated with inaccurate assessment, recall bias, and social desirability bias, are well-known; children under 10 years cannot report their activities accurately. However, despite such limitations, questionnaires are still the dominant method of physical activity assessment in dietary surveys due to their low cost and relatively low participant burden. Objective, time-stamped measures that monitor heart rate and/or movement can provide more comprehensive, quantitative assessment of physical activity but at greater cost and participant burden. Although overcoming many limitations of questionnaires, objective measures also have drawbacks, including technical, practical and interpretational issues.

Searching for Authentic Context in Designing PISA-like Mathematics Problem: From Indoor to Outdoor Field Experience

NASA Astrophysics Data System (ADS)

Siswono, T. Y. E.; Kohar, A. W.; Rosyidi, A. H.; Hartono, S.; Masriyah

2018-01-01

Designing problem like in PISA is known as a challenging activity for teachers particularly as the use of authentic context within that type of problem. This paper aims to describe the experiences of secondary mathematics teachers in designing PISA-like problems within an innovative training program focusing on building teachers’ understanding on the concept of mathematical literacy. The teachers were engaged in a set of problem-solving and problem-posing activities using PISA-based problem within indoor and outdoor field experiences. Within indoor field experience, the teachers worked collaboratively in groups on designing PISA-like problems with a given context through problem generation and reformulation techniques. Within outdoor field experience, they worked on designing PISA-like problems with self-chosen context from the place where the outdoor field experience took place. Our analysis indicates that there were improvements on the PISA-like problems designed by teachers based on its level use of context from indoor to outdoor experience. Also, the teachers were relatively successful with creating appropriate and motivating contexts by harnessing a variety of context consisting of personal, occupational, societal, and scientific contexts. However, they still experienced difficulties in turning these contexts into an appropriate problem satisfying PISA framework such as regarding authenticity of context use, language structure, and PISA task profile.

Writing to Learn Statistics in an Advanced Placement Statistics Course

ERIC Educational Resources Information Center

Northrup, Christian Glenn

2012-01-01

This study investigated the use of writing in a statistics classroom to learn if writing provided a rich description of problem-solving processes of students as they solved problems. Through analysis of 329 written samples provided by students, it was determined that writing provided a rich description of problem-solving processes and enabled…

Molecular deconstruction, detection, and computational prediction of microenvironment-modulated cellular responses to cancer therapeutics

PubMed Central

LaBarge, Mark A; Parvin, Bahram; Lorens, James B

2014-01-01

The field of bioengineering has pioneered the application of new precision fabrication technologies to model the different geometric, physical or molecular components of tissue microenvironments on solid-state substrata. Tissue engineering approaches building on these advances are used to assemble multicellular mimetic-tissues where cells reside within defined spatial contexts. The functional responses of cells in fabricated microenvironments has revealed a rich interplay between the genome and extracellular effectors in determining cellular phenotypes, and in a number of cases has revealed the dominance of microenvironment over genotype. Precision bioengineered substrata are limited to a few aspects, whereas cell/tissue-derived microenvironments have many undefined components. Thus introducing a computational module may serve to integrate these types of platforms to create reasonable models of drug responses in human tissues. This review discusses how combinatorial microenvironment microarrays and other biomimetic microenvironments have revealed emergent properties of cells in particular microenvironmental contexts, the platforms that can measure phenotypic changes within those contexts, and the computational tools that can unify the microenvironment-imposed functional phenotypes with underlying constellations of proteins and genes. Ultimately we propose that a merger of these technologies will enable more accurate pre-clinical drug discovery. PMID:24582543

Soil stabilization linked to plant diversity and environmental context in coastal wetlands.

PubMed

Ford, Hilary; Garbutt, Angus; Ladd, Cai; Malarkey, Jonathan; Skov, Martin W

2016-03-01

Plants play a pivotal role in soil stabilization, with above-ground vegetation and roots combining to physically protect soil against erosion. It is possible that diverse plant communities boost root biomass, with knock-on positive effects for soil stability, but these relationships are yet to be disentangled. We hypothesize that soil erosion rates fall with increased plant species richness, and test explicitly how closely root biomass is associated with plant diversity. We tested this hypothesis in salt marsh grasslands, dynamic ecosystems with a key role in flood protection. Using step-wise regression, the influences of biotic (e.g. plant diversity) and abiotic variables on root biomass and soil stability were determined for salt marshes with two contrasting soil types: erosion-resistant clay (Essex, southeast UK) and erosion-prone sand (Morecambe Bay, northwest UK). A total of 132 (30-cm depth) cores of natural marsh were extracted and exposed to lateral erosion by water in a re-circulating flume. Soil erosion rates fell with increased plant species richness ( R 2  = 0.55), when richness was modelled as a single explanatory variable, but was more important in erosion-prone ( R 2  = 0.44) than erosion-resistant ( R 2  = 0.18) regions. As plant species richness increased from two to nine species·m -2 , the coefficient of variation in soil erosion rate decreased significantly ( R 2  = 0.92). Plant species richness was a significant predictor of root biomass ( R 2  = 0.22). Step-wise regression showed that five key variables accounted for 80% of variation in soil erosion rate across regions. Clay-silt fraction and soil carbon stock were linked to lower rates, contributing 24% and 31%, respectively, to variation in erosion rate. In regional analysis, abiotic factors declined in importance, with root biomass explaining 25% of variation. Plant diversity explained 12% of variation in the erosion-prone sandy region. Our study indicates that soil stabilization and root biomass are positively associated with plant diversity. Diversity effects are more pronounced in biogeographical contexts where soils are erosion-prone (sandy, low organic content), suggesting that the pervasive influence of biodiversity on environmental processes also applies to the ecosystem service of erosion protection.

Saying good goodbyes to your clients: A functional analytic psychotherapy (FAP) perspective.

PubMed

Tsai, Mavis; Gustafsson, Tore; Kanter, Jonathan; Plummer Loudon, Mary; Kohlenberg, Robert J

2017-03-01

Functional analytic psychotherapy (FAP) promotes client growth by shaping clients' daily life problems that also show up in session with their therapists. FAP therapists create evocative contexts within therapy that afford clients the opportunity to practice, refine, and be reinforced for new, more adaptive behaviors which then can be generalized into their outside lives. In FAP, the termination process will vary from client to client depending on the nature of the client's problems and targets. For many clients, the process can be a rich, multifaceted, final opportunity to evoke, reinforce, and promote generalization of clients' in-session improvements, particularly improvements related to vulnerable self-expression in the service of intimate and close relationships. By making explicit agreements at the outset of therapy to participate in an intentional termination process, and by later providing an evocative structure for ending therapy with vulnerable emotional expression, clients have the opportunity to develop more adaptive behaviors in the context of relationship endings which can be a painful part of the human experience. Equipped with the skills of open-hearted communication developed from an authentic relationship with their therapist, clients can leave therapy on a trajectory of further growth in interpersonal connection and living more boldly. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

At the crossroads: new paradigms of food security, public health nutrition and school food.

PubMed

Ashe, Leah M; Sonnino, Roberta

2013-06-01

Public health nutrition sits at the nexus of a global crisis in food, environmental and health systems that has generated - along with numerous other problems - an urgent and changing problem of food insecurity. The 'new' food insecurity, however, is different from the old: it is bimodal, encompassing issues of both under- and over-consumption, hunger and obesity, quantity and quality; it has assumed a decidedly urban dimension; and it implicates rich and poor countries alike. The complexity of the expressions of this challenge requires new approaches to public health nutrition and food policy that privilege systemic, structural and environmental factors over individual and mechanistic ones. In this context, the current paper argues that school food systems rise with buoyant potential as promising intervention sites: they are poised to address both modes of the food security crisis; integrate systemic, structural and environmental with behavioural approaches; and comprise far-reaching, system-wide efforts that influence the wider functioning of the food system. Based on a discussion of Bogotá and other pioneering policies that explicitly aim to create a broader food system with long-term foundations for good public health and food security, the paper suggests a new research and action agenda that gives special attention to school food in urban contexts.

Testing alternative explanations for common responses to conceptual questions: An example in the context of center of mass

NASA Astrophysics Data System (ADS)

Heron, Paula R. L.

2017-06-01

In physics education research it has been common to interpret student errors on conceptual questions in topic-specific ways, rather than in terms of general perceptual or reasoning difficulties. This paper examines two alternative accounts for responses to questions related to the concept of center of mass. In one account, difficulties are said to be perceptual in nature; in the other, difficulties are said to be tightly linked to the concepts in question. Hypotheses derived from the former perspective are tested in studies conducted among university students in introductory physics courses. The results do not provide strong support for the perceptual hypothesis; in fact, there is evidence that performance on perception tasks may be influenced by subjects' ideas about the physical scenario. While the results do not provide general support for one perspective versus the other, the paper serves as an illustration of the type of investigation needed to develop the kind of rich representation of student thinking that will allow instructional resources to be most effectively targeted.

The Emotional Impact of Being Myself: Emotions and Foreign-Language Processing

ERIC Educational Resources Information Center

Ivaz, Lela; Costa, Albert; Duñabeitia, Jon Andoni

2016-01-01

Native languages are acquired in emotionally rich contexts, whereas foreign languages are typically acquired in emotionally neutral academic environments. As a consequence of this difference, it has been suggested that bilinguals' emotional reactivity in foreign-language contexts is reduced as compared with native language contexts. In the current…

Storytelling: A Strategy for Providing Context for Learning.

PubMed

Billings, Diane M

2016-03-01

Storytelling--a narrative of events related to nursing and linked to evidence--provides a context for learning, particularly for learners who require a rich context to understand and integrate concepts related to patient care. This article offers suggestions for developing and using stories in nursing education. Copyright 2016, SLACK Incorporated.

PREFACE: 17th International School on Condensed Matter Physics (ISCMP): Open Problems in Condensed Matter Physics, Biomedical Physics and their Applications

NASA Astrophysics Data System (ADS)

Dimova-Malinovska, Doriana; Nesheva, Diana; Pecheva, Emilia; Petrov, Alexander G.; Primatarowa, Marina T.

2012-12-01

We are pleased to introduce the Proceedings of the 17th International School on Condensed Matter Physics: Open Problems in Condensed Matter Physics, Biomedical Physics and their Applications, organized by the Institute of Solid State Physics of the Bulgarian Academy of Sciences. The Chairman of the School was Professor Alexander G Petrov. Like prior events, the School took place in the beautiful Black Sea resort of Saints Constantine and Helena near Varna, going back to the refurbished facilities of the Panorama hotel. Participants from 17 different countries delivered 31 invited lecturers and 78 posters, contributing through three sessions of poster presentations. Papers submitted to the Proceedings were refereed according to the high standards of the Journal of Physics: Conference Series and the accepted papers illustrate the diversity and the high level of the contributions. Not least significant factor for the success of the 17 ISCMP was the social program, both the organized events (Welcome and Farewell Parties) and the variety of pleasant local restaurants and beaches. Visits to the Archaeological Museum (rich in valuable gold treasures of the ancient Thracian culture) and to the famous rock monastery Aladja were organized for the participants from the Varna Municipality. These Proceedings are published for the second time by the Journal of Physics: Conference Series. We are grateful to the Journal's staff for supporting this idea. The Committee decided that the next event will take place again in Saints Constantine and Helena, 1-5 September 2014. It will be entitled: Challenges of the Nanoscale Science: Theory, Materials and Applications. Doriana Dimova-Malinovska, Diana Nesheva, Emilia Pecheva, Alexander G Petrov and Marina T Primatarowa Editors

The Effect of Friction in Pulleys on the Tension in Cables and Strings

NASA Astrophysics Data System (ADS)

Martell, Eric C.; Martell, Verda Beth

2013-02-01

Atwood's machine is used in countless introductory physics classes as an illustration of Newton's second law. Initially, the analysis is performed assuming the pulley and string are massless and the axle is frictionless. Although the mass of the pulley is often included when the problem is revisited later in the context of rotational dynamics, the mass of the string and the friction associated with the axle are less frequently discussed. Two questions then arise: 1) If we are ignoring these effects, how realistic is our model? and 2) How can we determine when or if we need to incorporate these effects in order to make our model match up with reality? These questions are connected to fundamental issues faced by physics teachers, namely the frustration students sometimes feel when they do not see how they can use the results of the problems they have been working on and how we can help our students develop effective models for physical systems.

The physics of life: one molecule at a time

PubMed Central

Leake, Mark C.

2013-01-01

The esteemed physicist Erwin Schrödinger, whose name is associated with the most notorious equation of quantum mechanics, also wrote a brief essay entitled ‘What is Life?’, asking: ‘How can the events in space and time which take place within the spatial boundary of a living organism be accounted for by physics and chemistry?’ The 60+ years following this seminal work have seen enormous developments in our understanding of biology on the molecular scale, with physics playing a key role in solving many central problems through the development and application of new physical science techniques, biophysical analysis and rigorous intellectual insight. The early days of single-molecule biophysics research was centred around molecular motors and biopolymers, largely divorced from a real physiological context. The new generation of single-molecule bioscience investigations has much greater scope, involving robust methods for understanding molecular-level details of the most fundamental biological processes in far more realistic, and technically challenging, physiological contexts, emerging into a new field of ‘single-molecule cellular biophysics’. Here, I outline how this new field has evolved, discuss the key active areas of current research and speculate on where this may all lead in the near future. PMID:23267186

The Integration of Care and Education: A Case Study concerning the Problem of Noise

ERIC Educational Resources Information Center

Kishimoto, Tizuko Morchida

2012-01-01

This article presents a study in the context of action-research performed on three-year-old children at an early childhood education centre in Sao Paulo, Brazil aiming at controlling the high noise level and ensuring the well-being of children and adults. Well-being is perceived as a state of physical and psychological satisfaction, and is a…

Army Ecosystem Management Policy Study

DTIC Science & Technology

1997-03-01

natural resources. A new generation of environmental issues is now upon us, defined by greater political, economic, social , and even cultural complexity...be established according to physical and biological criteria, and should account for the regional political, social , economic, and cultural context...speaks to what is known or what is knowable about a problem or situation. This determination is heavily influenced by social values and perceptions. We

The role of physical habitat and sampling effort on estimates of benthic macroinvertebrate taxonomic richness at basin and site scales.

PubMed

Silva, Déborah R O; Ligeiro, Raphael; Hughes, Robert M; Callisto, Marcos

2016-06-01

Taxonomic richness is one of the most important measures of biological diversity in ecological studies, including those with stream macroinvertebrates. However, it is impractical to measure the true richness of any site directly by sampling. Our objective was to evaluate the effect of sampling effort on estimates of macroinvertebrate family and Ephemeroptera, Plecoptera, and Trichoptera (EPT) genera richness at two scales: basin and stream site. In addition, we tried to determine which environmental factors at the site scale most influenced the amount of sampling effort needed. We sampled 39 sites in the Cerrado biome (neotropical savanna). In each site, we obtained 11 equidistant samples of the benthic assemblage and multiple physical habitat measurements. The observed basin-scale richness achieved a consistent estimation from Chao 1, Jack 1, and Jack 2 richness estimators. However, at the site scale, there was a constant increase in the observed number of taxa with increased number of samples. Models that best explained the slope of site-scale sampling curves (representing the necessity of greater sampling effort) included metrics that describe habitat heterogeneity, habitat structure, anthropogenic disturbance, and water quality, for both macroinvertebrate family and EPT genera richness. Our results demonstrate the importance of considering basin- and site-scale sampling effort in ecological surveys and that taxa accumulation curves and richness estimators are good tools for assessing sampling efficiency. The physical habitat explained a significant amount of the sampling effort needed. Therefore, future studies should explore the possible implications of physical habitat characteristics when developing sampling objectives, study designs, and calculating the needed sampling effort.

An investigation on a two-dimensional problem of Mode-I crack in a thermoelastic medium

NASA Astrophysics Data System (ADS)

Kant, Shashi; Gupta, Manushi; Shivay, Om Namha; Mukhopadhyay, Santwana

2018-04-01

In this work, we consider a two-dimensional dynamical problem of an infinite space with finite linear Mode-I crack and employ a recently proposed heat conduction model: an exact heat conduction with a single delay term. The thermoelastic medium is taken to be homogeneous and isotropic. However, the boundary of the crack is subjected to a prescribed temperature and stress distributions. The Fourier and Laplace transform techniques are used to solve the problem. Mathematical modeling of the present problem reduces the solution of the problem into the solution of a system of four dual integral equations. The solution of these equations is equivalent to the solution of the Fredholm's integral equation of the first kind which has been solved by using the regularization method. Inverse Laplace transform is carried out by using the Bellman method, and we obtain the numerical solution for all the physical field variables in the physical domain. Results are shown graphically, and we highlight the effects of the presence of crack in the behavior of thermoelastic interactions inside the medium in the present context, and its results are compared with the results of the thermoelasticity of type-III.

Soft matter perspective on protein crystal assembly.

PubMed

Fusco, Diana; Charbonneau, Patrick

2016-01-01

Crystallography may be the gold standard of protein structure determination, but obtaining the necessary high-quality crystals is also in some ways akin to prospecting for the precious metal. The tools and models developed in soft matter physics to understand colloidal assembly offer some insights into the problem of crystallizing proteins. This topical review describes the various analogies that have been made between proteins and colloids in that context. We highlight the explanatory power of patchy particle models, but also the challenges of providing guidance for crystallizing specific proteins. We conclude with a presentation of possible future research directions. This review is intended for soft matter scientists interested in protein crystallization as a self-assembly problem, and as an introduction to the pertinent physics literature for protein scientists more generally. Copyright © 2015 Elsevier B.V. All rights reserved.

Developing a Theoretical Framework for Classifying Levels of Context Use for Mathematical Problems

ERIC Educational Resources Information Center

Almuna Salgado, Felipe

2016-01-01

This paper aims to revisit and clarify the term problem context and to develop a theoretical classification of the construct of levels of context use (LCU) to analyse how the context of a problem is used to formulate a problem in mathematical terms and to interpret the answer in relation to the context of a given problem. Two criteria and six…

Fitting in to Move Forward: How Belonging Affects Women in Physics

NASA Astrophysics Data System (ADS)

Ito, Tiffany

2017-01-01

This talk will consider different factors that have been shown to negatively affect women in physics and other STEM fields by decreasing their subjective sense of belonging, fit, and acceptance. I will discuss recent studies documenting gender disparities in belonging and the negative effect this has on women's persistence. I will also consider the effects of gender composition within group problem-solving tasks on women's belonging, behavior, and perceived competency. Finally, I will discuss potential interventions and changes in classroom context that may serve to encourage women and members of other underrepresented groups.

Underworld results as a triple (shopping list, posterior, priors)

NASA Astrophysics Data System (ADS)

Quenette, S. M.; Moresi, L. N.; Abramson, D.

2013-12-01

When studying long-term lithosphere deformation and other such large-scale, spatially distinct and behaviour rich problems, there is a natural trade-off between the meaning of a model, the observations used to validate the model and the ability to compute over this space. For example, many models of varying lithologies, rheological properties and underlying physics may reasonably match (or not match) observables. To compound this problem, each realisation is computationally intensive, requiring high resolution, algorithm tuning and code tuning to contemporary computer hardware. It is often intractable to use sampling based assimilation methods, but with better optimisation, the window of tractability becomes wider. The ultimate goal is to find a sweet-spot where a formal assimilation method is used, and where a model affines to observations. Its natural to think of this as an inverse problem, in which the underlying physics may be fixed and the rheological properties and possibly the lithologies themselves are unknown. What happens when we push this approach and treat some portion of the underlying physics as an unknown? At its extreme this is an intractable problem. However, there is an analogy here with how we develop software for these scientific problems. What happens when we treat the changing part of a largely complete code as an unknown, where the changes are working towards this sweet-spot? When posed as a Bayesian inverse problem the result is a triple - the model changes, the real priors and the real posterior. Not only does this give meaning to the process by which a code changes, it forms a mathematical bridge from an inverse problem to compiler optimisations given such changes. As a stepping stone example we show a regional scale heat flow model with constraining observations, and the inverse process including increasingly complexity in the software. The implementation uses Underworld-GT (Underworld plus research extras to import geology and export geothermic measures, etc). Underworld uses StGermain an early (partial) implementation of the theories described here.

Modeling science: Supporting a more authentic epistemology of science

NASA Astrophysics Data System (ADS)

Svoboda, Julia Marie

In this dissertation I argue that model-based inquiry has the potential to create experiences for students to consider how scientific knowledge is generated and evaluated - that is, for students to consider the epistemology of science. I also argue that such epistemically rich experiences can lead to shifts in students' conceptions of the nature of scientific knowledge. The context of this work is a yearlong biological modeling traineeship for undergraduate mathematics and biology majors called Collaborative Learning at the Interface of Mathematics and Biology (CLIMB). I used an ethnographically-based approach to collect detailed field notes, video, documents and interviews with faculty and students in CLIMB. The resulting dataset provides a rich description of the CLIMB program as well as students experiences in this program. Analysis of the CLIMB curriculum revealed that the degree to which students were treated as independent scholars and challenged with authentic problems influenced the productivity of their activity. A more detailed analysis of the nature of modeling tasks revealed that only when models were at the center of their activity did students have opportunities to consider epistemic themes relating to how knowledge is created and critiqued in science. Finally, a case study that followed a single student described how rich epistemically rich experiences with modeling have the potential to shift the ways in which students conceive of scientific knowledge and practice. It also provided evidence that supports the theory that students have complex multidimensional epistemic ecologies as opposed to static views about science. As a whole, this dissertation provides a rich description of how model-based inquiry can support learning about the epistemology of science and suggests that scientific modeling should have a more central role in science education.

The Dreyfus model of clinical problem-solving skills acquisition: a critical perspective

PubMed Central

Peña, Adolfo

2010-01-01

Context The Dreyfus model describes how individuals progress through various levels in their acquisition of skills and subsumes ideas with regard to how individuals learn. Such a model is being accepted almost without debate from physicians to explain the ‘acquisition’ of clinical skills. Objectives This paper reviews such a model, discusses several controversial points, clarifies what kind of knowledge the model is about, and examines its coherence in terms of problem-solving skills. Dreyfus' main idea that intuition is a major aspect of expertise is also discussed in some detail. Relevant scientific evidence from cognitive science, psychology, and neuroscience is reviewed to accomplish these aims. Conclusions Although the Dreyfus model may partially explain the ‘acquisition’ of some skills, it is debatable if it can explain the acquisition of clinical skills. The complex nature of clinical problem-solving skills and the rich interplay between the implicit and explicit forms of knowledge must be taken into consideration when we want to explain ‘acquisition’ of clinical skills. The idea that experts work from intuition, not from reason, should be evaluated carefully. PMID:20563279

Using Rich Context and Data Exploration to Improve Engagement with Climate Data and Data Literacy: Bringing a Field Station into the College Classroom

ERIC Educational Resources Information Center

Ellwein, Amy L.; Hartley, Laurel M.; Donovan, Sam; Billick, Ian

2014-01-01

Authentic scientific data, when richly contextualized, can provide the basis for compelling learning experiences. Many undergraduate students either do not have access to primary data, or if they do, the data are so abstract that student engagement is limited. Here, we describe contextual information and data-rich, student-centered activities we…

Conceptual Developments of 20th Century Field Theories

NASA Astrophysics Data System (ADS)

Cao, Tian Yu

1998-06-01

This volume provides a broad synthesis of conceptual developments of twentieth century field theories, from the general theory of relativity to quantum field theory and gauge theory. The book traces the foundations and evolution of these theories within a historio-critical context. Theoretical physicists and students of theoretical physics will find this a valuable account of the foundational problems of their discipline that will help them understand the internal logic and dynamics of theoretical physics. It will also provide professional historians and philosophers of science, particularly philosophers of physics, with a conceptual basis for further historical, cultural and sociological analysis of the theories discussed. Finally, the scientifically qualified general reader will find in this book a deeper analysis of contemporary conceptions of the physical world than can be found in popular accounts of the subject.

Conceptual Developments of 20th Century Field Theories

NASA Astrophysics Data System (ADS)

Cao, Tian Yu

1997-02-01

This volume provides a broad synthesis of conceptual developments of twentieth century field theories, from the general theory of relativity to quantum field theory and gauge theory. The book traces the foundations and evolution of these theories within a historio-critical context. Theoretical physicists and students of theoretical physics will find this a valuable account of the foundational problems of their discipline that will help them understand the internal logic and dynamics of theoretical physics. It will also provide professional historians and philosophers of science, particularly philosophers of physics, with a conceptual basis for further historical, cultural and sociological analysis of the theories discussed. Finally, the scientifically qualified general reader will find in this book a deeper analysis of contemporary conceptions of the physical world than can be found in popular accounts of the subject.

Replacing textbook problems with lab experiences

NASA Astrophysics Data System (ADS)

Register, Trevor

2017-10-01

End-of-the-chapter textbook problems are often the bread and butter of any traditional physics classroom. However, research strongly suggests that students be given the opportunity to apply their knowledge in multiple contexts as well as be provided with opportunities to do the process of science through laboratory experiences. Little correlation has been shown linking the number of textbook problems solved with conceptual understanding of topics in mechanics. Furthermore, textbook problems as the primary source of practice for students robs them of the joy and productive struggle of learning how to think like an experimental physicist. Methods such as Modeling Instruction tackle this problem head-on by starting each instructional unit with an inquiry-based lab aimed at establishing the important concepts and equations for the unit, and this article will discuss ideas and experiences for how to carry that philosophy throughout a unit.

On the existence of solutions to a one-dimensional degenerate nonlinear wave equation

NASA Astrophysics Data System (ADS)

Hu, Yanbo

2018-07-01

This paper is concerned with the degenerate initial-boundary value problem to the one-dimensional nonlinear wave equation utt =((1 + u) aux) x which arises in a number of various physical contexts. The global existence of smooth solutions to the degenerate problem was established under relaxed conditions on the initial-boundary data by the characteristic decomposition method. Moreover, we show that the solution is uniformly C 1 , α continuous up to the degenerate boundary and the degenerate curve is C 1 , α continuous for α ∈ (0 , min ⁡ a/1+a, 1/1+a).

Advantages of heterogeneous therapy groups in the psychotherapy of the traumatically abused: treating the problem as well as the person.

PubMed

Nicholas, M; Forrester, A

1999-07-01

The authors combine a social-constructionist perspective with a psychodynamic one in discussing the problem of trauma and its treatment. They argue that effective treatment of traumatic physical, sexual, and psychological abuse must do more than alleviate the pain of the sufferer. Factors that cause and perpetuate abuse must be addressed by the abused person in conjunction with other nontraumatized persons who may have been abusive or passive in the face of abuse. An argument is made for heterogeneous therapy groups as a context for this to occur.

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

Dinh, Nam; Athe, Paridhi; Jones, Christopher

The Virtual Environment for Reactor Applications (VERA) code suite is assessed in terms of capability and credibility against the Consortium for Advanced Simulation of Light Water Reactors (CASL) Verification and Validation Plan (presented herein) in the context of three selected challenge problems: CRUD-Induced Power Shift (CIPS), Departure from Nucleate Boiling (DNB), and Pellet-Clad Interaction (PCI). Capability refers to evidence of required functionality for capturing phenomena of interest while capability refers to the evidence that provides confidence in the calculated results. For this assessment, each challenge problem defines a set of phenomenological requirements against which the VERA software is assessed. Thismore » approach, in turn, enables the focused assessment of only those capabilities relevant to the challenge problem. The evaluation of VERA against the challenge problem requirements represents a capability assessment. The mechanism for assessment is the Sandia-developed Predictive Capability Maturity Model (PCMM) that, for this assessment, evaluates VERA on 8 major criteria: (1) Representation and Geometric Fidelity, (2) Physics and Material Model Fidelity, (3) Software Quality Assurance and Engineering, (4) Code Verification, (5) Solution Verification, (6) Separate Effects Model Validation, (7) Integral Effects Model Validation, and (8) Uncertainty Quantification. For each attribute, a maturity score from zero to three is assigned in the context of each challenge problem. The evaluation of these eight elements constitutes the credibility assessment for VERA.« less

The Coming Revolutions in Particle Physics

ScienceCinema

Quigg, Chris

2017-12-09

Wonderful opportunities await particle physics over the next decade, with new instruments and experiments poised to explore the frontiers of high energy, infinitesimal distances, and exquisite rarity. We look forward to the Large Hadron Collider at CERN to explore the 1-TeV scale (extending efforts at LEP and the Tevatron to unravel the nature of electroweak symmetry breaking) and many initiatives to develop our understanding of the problem of identity: what makes a neutrino a neutrino and a top quark a top quark. We suspect that the detection of proton decay is only a few orders of magnitude away in sensitivity. Astronomical observations should help to tell us what kinds of matter and energy make up the universe. We might even learn to read experiment for clues about the dimensionality of spacetime. If we are inventive enough, we may be able to follow this rich menu with the physics opportunities offered by a linear electron-positron collider and a (muon storage ring) neutrino factory. I expect a remarkable flowering of experimental particle physics, and of theoretical physics that engages with experiment.

Exposure to air pollution and self-reported effects on Chinese students: A case study of 13 megacities

PubMed Central

2018-01-01

Air pollution causes severe physical and psychological health complications. Considering China’s continuously-deteriorating air quality, this study aimed to assess the self-reported effects of air pollution on the behavior and physical health of the students of 13 densely populated cities, and their awareness, practices, and perception of air pollution and its associated public health risks. A detailed, closed-ended questionnaire was administered to 2100 students from 54 universities and schools across China. The questionnaire, which had 24 questions, was categorized into four sections. The first two sections were focused on air pollution-associated behavior and psychology, and physical effects; while the final two sections focused on the subjects’ awareness and perceptions, and practices and concerns about air pollution. The respondents reported that long-term exposure to air pollution had significantly affected their psychology and behavior, as well as their physical health. The respondents were aware of the different adverse impacts of air pollution (respiratory infections, allergies, and cardiovascular problems), and hence had adopted different preventive measures, such as the use of respiratory masks and glasses or goggles, regularly drinking water, and consuming rich foods. It was concluded that air pollution and haze had negative physical and psychological effects on the respondents, which led to severe changes in behavior. Proper management, future planning, and implementing strict environmental laws are suggested before this problem worsens and becomes life-threatening. PMID:29547657

Problem Solving in Technology-Rich Environments. A Report from the NAEP Technology-Based Assessment Project, Research and Development Series. NCES 2007-466

ERIC Educational Resources Information Center

Bennett, Randy Elliot; Persky, Hilary; Weiss, Andrew R.; Jenkins, Frank

2007-01-01

The Problem Solving in Technology-Rich Environments (TRE) study was designed to demonstrate and explore innovative use of computers for developing, administering, scoring, and analyzing the results of National Assessment of Educational Progress (NAEP) assessments. Two scenarios (Search and Simulation) were created for measuring problem solving…

Massive stars: privileged sources of cosmic-rays for interstellar astrochemistry

NASA Astrophysics Data System (ADS)

De Becker, M.

2015-01-01

Massive stars can be considered as crucial engines for interstellar physics. They are indeed the main providers of UV radiation field, and constitute a substantial source of chemical enrichment. On their evolution time-scale (at most about 10 Myr), they typically stay close to their formation site, i.e. close to molecular clouds very rich in interstellar molecules. These stellar objects have also the property to be involved in particle acceleration processes leading to the production of high energy charged particles (cosmic-rays). After rejection in the interstellar medium, these particles will play a substantial role in processes such as those simulated in various facilities dedicated to experimental astrochemistry. This short contribution intends to put these particles, crucial for astrochemistry, in their adequate astrophysical context.

Numerical Simulation of Two-Fluid Mingling Using the Particle Finite Element Method with Applications to Magmatic and Volcanic Processes

NASA Astrophysics Data System (ADS)

de Mier, M.; Costa, F.; Idelsohn, S.

2008-12-01

Many magmatic and volcanic processes (e.g., magma differentiation, mingling, transport in the volcanic conduit) are controlled by the physical properties and flow styles of high-temperature silicate melts. Such processes can be experimentally investigated using analog systems and scaling methods, but it is difficult to find the suitable material and it is generally not possible to quantitatively extrapolate the results to the natural system. An alternative means of studying fluid dynamics in volcanic systems is with numerical models. We have chosen the Particle Finite Element Method (PFEM), which is based on a Delaunay mesh that moves with the fluid velocity, the Navier-Stokes equations in Lagrangian formulation, and linear elements for velocity, pressure, and temperature. Remeshing is performed when the grid becomes too distorted [E. Oñate et al., 2004. The Particle Finite Element Method: An Overview. Int. J. Comput. Meth. 1, 267-307]. The method is ideal for tracking material interfaces between different fluids or media. Methods based on Eulerian reference frames need special techniques, such as level-set or volume-of-fluid, to capture the interface position, and these techniques add a significant numerical diffusion at the interface. We have performed a series of two-dimensional simulations of a classical problem of fluid dynamics in magmatic and volcanic systems: intrusion of a basaltic melt in a silica-rich magma reservoir. We have used realistic physical properties and equations of state for the silicate melts (e.g., temperature, viscosity, and density) and tracked the changes in the system for geologically relevant time scales (up to 100 years). The problem is modeled by the low-Mach-number equations derived from an asymptotic analysis of the compressible Navier-Stokes equations that removes shock waves from the flow but allows however large variations of density due to temperature variations. Non-constant viscosity and volume changes are taken into account in the momentum conservation equation through the full shear-stress tensor. The implications of different magma intrusion rates, volumes, and times will be discussed in the context of mafic-silicic magma mixing and eruption triggers.

Careers in Government: Bench Scientist to Policy Wonk

NASA Astrophysics Data System (ADS)

Gebbie, Katharine B.

1998-04-01

The U.S. system for graduate education in physics is arguably the most effective system yet devised for advanced training in physics. Focused as it is on original research, it teaches students to identify significant problems, study them in depth, and communicate the results. Because it trains them to be analytical, adaptable, persevering, and pragmatic problem solvers, it prepares them for a wide variety of nontraditional careers. Hence the demand for physicists by Wall Street and management consultant teams. Yet, as stressed in the 1995 report by the Committee on Science, Engineering and Public Policy (COSEPUP)("Reshaping the Graduate Education of Scientists and Engineers," COSEPUP; National Academy of Sciences/National Academy of Engineering/Institute of Medicine. National Academy Press, 1995), what is lacking is exposure to career information and guidance. Many students appear to be unaware of the range and richness of opportunities outside academe. In an effort to fill this gap, illustrative examples of diverse careers and career changes in government will be presented, together with examples of cooperative programs that can enhance the student's appreciation of career possibilities.

RICH detectors: Analysis methods and their impact on physics

NASA Astrophysics Data System (ADS)

Križan, Peter

2017-12-01

The paper discusses the importance of particle identification in particle physics experiments, and reviews the impact of ring imaging Cherenkov (RICH) counters in experiments that are currently running, or are under construction. Several analysis methods are discussed that are needed to calibrate a RICH counter, and to align its components with the rest of the detector. Finally, methods are reviewed on how to employ the collected data to efficiently separate one particle species from the other.

Physical pretreatment of biogenic-rich trommel fines for fast pyrolysis.

PubMed

Eke, Joseph; Onwudili, Jude A; Bridgwater, Anthony V

2017-12-01

Energy from Waste (EfW) technologies such as fluidized bed fast pyrolysis, are beneficial for both energy generation and waste management. Such technologies, however face significant challenges due to the heterogeneous nature, particularly the high ash contents of some municipal solid waste types e.g. trommel fines. A study of the physical/mechanical and thermal characteristics of these complex wastes is important for two main reasons; (a) to inform the design and operation of pyrolysis systems to handle the characteristics of such waste; (b) to control/modify the characteristics of the waste to fit with existing EFW technologies via appropriate feedstock preparation methods. In this study, the preparation and detailed characterisation of a sample of biogenic-rich trommel fines has been carried out with a view to making the feedstock suitable for fast pyrolysis based on an existing fluidized bed reactor. Results indicate that control of feed particle size was very important to prevent problems of dust entrainment in the fluidizing gas as well as to prevent feeder hardware problems caused by large stones and aggregates. After physical separation and size reduction, nearly 70wt% of the trommel fines was obtained within the size range suitable for energy recovery using the existing fast pyrolysis system. This pyrolyzable fraction could account for about 83% of the energy content of the 'as received' trommel fines sample. Therefore there was no significant differences in the thermochemical properties of the raw and pre-treated feedstocks, indicating that suitably prepared trommel fines samples can be used for energy recovery, with significant reduction in mass and volume of the original waste. Consequently, this can lead to more than 90% reduction in the present costs of disposal of trommel fines in landfills. In addition, the recovered plastics and textile materials could be used as refuse derived fuel. Copyright © 2017 Elsevier Ltd. All rights reserved.

Analysis of a Physics Teacher's Pedagogical "Micro-Actions" That Support 17-Year-Olds' Learning of Free Body Diagrams via a Modelling Approach

ERIC Educational Resources Information Center

Tay, Su Lynn; Yeo, Jennifer

2018-01-01

Great teaching is characterised by the specific actions a teacher takes in the classroom to bring about learning. In the context of model-based teaching (MBT), teachers' difficulty in working with students' models that are not scientifically consistent is troubling. To address this problem, the aim of this study is to identify the pedagogical…

The birthplace of compact groups of galaxies

NASA Technical Reports Server (NTRS)

Ramella, Massimo; Diaferio, Antonaldo; Geller, Margaret J.; Huchra, John P.

1994-01-01

We use complete redshift surveys to study the redshift neighborhoods of 38 Hickson compact groups (HCGs). Twenty-nine of these HCGs (76%) are embedded in rich looser systems which we call HCG associations. Analysis of the redshift neighborhood of HCGs outside the CfA survey suggests that most HCGs are embedded in more extended physical systems. Rich loose groups extracted from the CfA survey (Ramella et al. (1994)) have physical properties similar to those of the HCG associations. These rich loose groups often contain compact configurations. N-body experiments (Diaferio (1994)) suggest that compact configurations analogous to HCGs form continually during the collapse of rich loose groups. These observational and numerical results suggest that rich loose groups are the birthplace of HCGs.

Baselines and null hypotheses for climate change: Phytoplankton biomass structure in the California Current

NASA Astrophysics Data System (ADS)

Landry, M. R.; Taylor, A. G.

2016-02-01

Phytoplankton community structure is shaped both by the bottom-up influences of the physical-chemical environment and by the top-down impacts of food webs. Emergent patterns in the contemporary ocean can thus be "null hypotheses" of future changes assuming that the underlying structuring relationships remain intact but only shift spatially. To provide such a context for the California Current Ecosystem (CCE) and adjacent open-ocean ecosystems, we used a combination of digital epifluorescence microscopy and flow cytometry to investigate variability of phytoplankton biomass, composition and size structure across gradients of ecosystem richness, as represented by total autotrophic carbon (AC). Biomass of large micro-sized (>20 µm) phytoplankton increases as a power function with system richness. Nano-sized cells (2-20 µm) increase at a lower rate at low AC, and level off at high AC. Pico-sized cells (<2-µm) do not clearly dominate at low AC and decline significantly at high AC, neither predicted by competition theory. This study provides several new insights into structural relationships and mechanisms in the CCE: 1) diatoms and dinoflagellates co-dominate the micro-phytoplankton size class throughout the range of system richness; 2) nano-phytoplankton co-dominate biomass in oligotrophic (low AC) waters, suggesting widespread mixotrophy rather than direct competition with pico-phytoplankton for nutrients; and 3) the pico-phytoplankton decline at high AC impacts small eukaryotes as well as photosynthetic bacteria, consistent with a broad stimulation of grazing pressure on all bacterial-sized cells in richer systems. Observed variability in heterotrophic bacteria and nano-flagellate grazers with system richness is consistent with this mechanism.

Problem-based learning in an on-line biotechnology course

NASA Astrophysics Data System (ADS)

Cheaney, James Daniel

Problem-based learning (PBL) is a pedagogical tool that uses a "real world" problem or situation as a context for learning. PBL encourages student development of critical thinking skills, a high professional competency, problem-solving ability, knowledge acquisition, the ability to work productively as a team member and make decisions in unfamiliar situations, and the acquisition of skills that support self-directed life-long learning, metacognition, and adaptation to change. However, little research has focused on the use of PBL in on-line "virtual" classes. We conducted two studies exploring the use of PBL in an on-line biotechnology course. In the first study, ethical, legal, social, and human issues were used as a motivation for learning about DNA testing technologies, applications, and bioethical issues. In the second study, we combined PBL pedagogy with a rich multimedia environment of streaming video interviews, physical artifacts, and extensive links to articles and databases to create a multidimensional immersive PBL environment called "Robert's World". In "Robert's World", a man is determining whether to undergo a pre-symptomatic DNA test for an untreatable, incurable, fatal genetic disease for which he has a family history. In both studies, design and implementation issues of the on-line PBL environment are discussed, as are differences between on-line PBL and face-to-face PBL. Both studies provide evidence to suggest that PBL stimulates higher-order learning in students. However, in both studies, student performance on an exam testing acquisition of lower-order factual learning was lower for PBL students than for students who learned the same material through a traditional lecture-based approach. Possible reasons for this lower level of performance are explored. Student feedback expressed engagement with the issues and material covered, with reservations about some aspects of the PBL format, such as the lack of flexibility provided in cooperative learning. We conclude that on-line PBL is a powerful tool in helping to develop higher-order learning in students. The reasons for the decrease in student understanding of factual information are unclear. However, there are certain circumstances unique to on-line classes to keep in mind when implementing on-line PBL. These are summarized in concluding recommendations.

Varying Use of Conceptual Metaphors across Levels of Expertise in Thermodynamics

NASA Astrophysics Data System (ADS)

Jeppsson, Fredrik; Haglund, Jesper; Amin, Tamer G.

2015-04-01

Many studies have previously focused on how people with different levels of expertise solve physics problems. In early work, focus was on characterising differences between experts and novices and a key finding was the central role that propositionally expressed principles and laws play in expert, but not novice, problem-solving. A more recent line of research has focused on characterising continuity between experts and novices at the level of non-propositional knowledge structures and processes such as image-schemas, imagistic simulation and analogical reasoning. This study contributes to an emerging literature addressing the coordination of both propositional and non-propositional knowledge structures and processes in the development of expertise. Specifically, in this paper, we compare problem-solving across two levels of expertise-undergraduate students of chemistry and Ph.D. students in physical chemistry-identifying differences in how conceptual metaphors (CMs) are used (or not) to coordinate propositional and non-propositional knowledge structures in the context of solving problems on entropy. It is hypothesised that the acquisition of expertise involves learning to coordinate the use of CMs to interpret propositional (linguistic and mathematical) knowledge and apply it to specific problem situations. Moreover, we suggest that with increasing expertise, the use of CMs involves a greater degree of subjective engagement with physical entities and processes. Implications for research on learning and instructional practice are discussed. Third contribution to special issue entitled: Conceptual metaphor and embodied cognition in science learning

A Neural Network Aero Design System for Advanced Turbo-Engines

NASA Technical Reports Server (NTRS)

Sanz, Jose M.

1999-01-01

An inverse design method calculates the blade shape that produces a prescribed input pressure distribution. By controlling this input pressure distribution the aerodynamic design objectives can easily be met. Because of the intrinsic relationship between pressure distribution and airfoil physical properties, a Neural Network can be trained to choose the optimal pressure distribution that would meet a set of physical requirements. Neural network systems have been attempted in the context of direct design methods. From properties ascribed to a set of blades the neural network is trained to infer the properties of an 'interpolated' blade shape. The problem is that, especially in transonic regimes where we deal with intrinsically non linear and ill posed problems, small perturbations of the blade shape can produce very large variations of the flow parameters. It is very unlikely that, under these circumstances, a neural network will be able to find the proper solution. The unique situation in the present method is that the neural network can be trained to extract the required input pressure distribution from a database of pressure distributions while the inverse method will still compute the exact blade shape that corresponds to this 'interpolated' input pressure distribution. In other words, the interpolation process is transferred to a smoother problem, namely, finding what pressure distribution would produce the required flow conditions and, once this is done, the inverse method will compute the exact solution for this problem. The use of neural network is, in this context, highly related to the use of proper optimization techniques. The optimization is used essentially as an automation procedure to force the input pressure distributions to achieve the required aero and structural design parameters. A multilayered feed forward network with back-propagation is used to train the system for pattern association and classification.

Negation in context: Evidence from the visual world paradigm.

PubMed

Orenes, Isabel; Moxey, Linda; Scheepers, Christoph; Santamaría, Carlos

2016-01-01

Literature assumes that negation is more difficult to understand than affirmation, but this might depend on the pragmatic context. The goal of this paper is to show that pragmatic knowledge modulates the unfolding processing of negation due to the previous activation of the negated situation. To test this, we used the visual world paradigm. In this task, we presented affirmative (e.g., her dad was rich) and negative sentences (e.g., her dad was not poor) while viewing two images of the affirmed and denied entities. The critical sentence in each item was preceded by one of three types of contexts: an inconsistent context (e.g., She supposed that her dad had little savings) that activates the negated situation (a poor man), a consistent context (e.g., She supposed that her dad had enough savings) that activates the actual situation (a rich man), or a neutral context (e.g., her dad lived on the other side of town) that activates neither of the two models previously suggested. The results corroborated our hypothesis. Pragmatics is implicated in the unfolding processing of negation. We found an increase in fixations on the target compared to the baseline for negative sentences at 800 ms in the neutral context, 600 ms in the inconsistent context, and 1450 ms in the consistent context. Thus, when the negated situation has been previously introduced via an inconsistent context, negation is facilitated.

Designing students’ worksheet based on open-ended approach to foster students’ creative thinking skills

NASA Astrophysics Data System (ADS)

Romli, S.; Abdurrahman; Riyadi, B.

2018-01-01

This study aimed at designing an open-ended worksheet to enhance students’ creative thinking skills. The study was conducted at one private school in Bandar Lampung, Indonesia. The participants of the study were twenty students of tenth grade students and two physics teachers. This study used descriptive data. Data were collected by analyzing qualitative data, literature and focus group discussion to gain information about students’ conceptions of physics in the context of open-ended learning. The result showed that students needed innovative learning resources in form of open ended-based worksheet which could give the students an opportunity to develop various solutions related to physics problem. Therefore, students’ creative thinking skill could be improved.

News Almost dry but never dull: ASE 2014 EuroPhysicsFun shows physics to Europe Institute of Physics for Africa (IOPfA) South Sudan Report October 2013 Celebrating the centenary of x-ray diffraction The Niels Bohr Institute—an EPS Historical Site Nordic Research Symposium on Science Education (NFSUN) 2014: inquiry-based science education in technology-rich environments Physics World Cup 2013

NASA Astrophysics Data System (ADS)

2014-03-01

Almost dry but never dull: ASE 2014 EuroPhysicsFun shows physics to Europe Institute of Physics for Africa (IOPfA) South Sudan Report October 2013 Celebrating the centenary of x-ray diffraction The Niels Bohr Institute—an EPS Historical Site Nordic Research Symposium on Science Education (NFSUN) 2014: inquiry-based science education in technology-rich environments Physics World Cup 2013

Community Discovery in Dynamic, Rich-Context Social Networks

ERIC Educational Resources Information Center

Lin, Yu-Ru

2010-01-01

My research interest has been in understanding the human communities formed through interpersonal social activities. Participation in online communities on social network sites such as Twitter has been observed to influence people's behavior in diverse ways including financial decision-making and political choices, suggesting the rich potential…

Citizen Science in the Classroom: Perils and Promise of the New Web

NASA Astrophysics Data System (ADS)

Loughran, T.; Dirksen, R.

2010-12-01

Classroom citizen science projects invite students to generate, curate, post, query, and analyze data, publishing and discussing results in potentially large collaborative contexts. The new web offers a rich palette of such projects for any STEM educator to select from or create. This easy access to citizen science in the classroom is full of both promise and peril for science education. By offering examples of classroom citizen science projects in particle physics, earth and environmental sciences, each supported by a common mashup of technologies available to ordinary users, we will illustrate something of the promise of these projects for science education, and point to some of the challenges and failure modes--the peril--raised by easy access and particularly easy publication of data. How one sensibly responds to this promise and peril depends on how one views the goals of science (or more broadly, STEM) education: either as the equipping of individual students with STEM knowledge and skills so as to empower them for future options, or as the issuing of effective invitations into STEM communities. Building on the claim that these are complementary perspectives, both of value, we will provide an example of a classroom citizen science project analyzed from both perspectives. The BOSCO classroom-to-classroom water source mapping project provides students both in Northern Uganda and in South Dakota a collaborative platform for analyzing and responding to local water quality concerns. Students gather water quality data, use Google Forms embedded in a project wiki to enter data in a spreadsheet, which then automatically (through Mapalist, a free web service) gets posted to a Google Map, itself embedded in the project wiki. Using these technologies, data is thus collected and posted for analysis in a collaborative environment: the stage is set for classroom citizen science. In the context of this project we will address the question of how teachers can take advantage of the new web to encourage students to become creative problem-solvers in online collaborative contexts without looking past the foundation of careful preparation and the standards of reliability associated with publication in the STEM disciplines.

Design of an assessment to probe teachers' content knowledge for teaching: An example from energy in high school physics

NASA Astrophysics Data System (ADS)

Etkina, Eugenia; Gitomer, Drew; Iaconangelo, Charles; Phelps, Geoffrey; Seeley, Lane; Vokos, Stamatis

2018-06-01

Research into teacher learning and practice over the last three decades shows that the teachers of a specific subject need to possess knowledge that is different from the knowledge of other content experts. Yet this specialized version of content knowledge that teachers need to plan instruction, respond to student ideas, and assess student understanding in real time is a theoretically elusive construct. It is crucial for the fields of precollege teacher preparation, teacher professional education, and postsecondary faculty professional development to (a) clarify the construct that underlies this specialized content knowledge, (b) operationalize it in some domain, (c) measure it in both static contexts and as it is enacted in the classroom, and (d) correlate its presence with "richness" of classroom instruction and its effect on student learning. This paper documents a piece of a multiyear, multi-institutional effort to investigate points (a)-(d) in the domain of energy in the first high school physics course. In particular, we describe the framework that we developed to clarify content knowledge for teaching in the context of high school energy learning. We then outline the process through which we developed, tested, and refined a "paper-and-pencil" assessment administered on a computer and discuss the substantive and psychometric features of several items based on a field test of the final form of the assessment. We choose to discuss these items for a dual purpose: to illustrate the application of our general framework and to present performance findings from a sample of 362 practicing high school teachers of physics.

How patients and clinicians make meaning of physical suffering in mental health evaluations.

PubMed

Carson, Nicholas J; Katz, Arlene M; Alegría, Margarita

2016-10-01

Clinicians in community mental health settings frequently evaluate individuals suffering from physical health problems. How patients make meaning of such "comorbidity" can affect mental health in ways that may be influenced by cultural expectations and by the responses of clinicians, with implications for delivering culturally sensitive care. A sample of 30 adult mental health intakes exemplifying physical illness assessment was identified from a larger study of patient-provider communication. The recordings of patient-provider interactions were coded using an information checklist containing 21 physical illness items. Intakes were analyzed for themes of meaning making by patients and responses by clinicians. Post-diagnostic interviews with these patients and clinicians were analyzed in similar fashion. Clinicians facilitated disclosures of physical suffering to varying degrees and formulated them in the context of the culture of mental health services. Patients discussed their perceptions of what was at stake in their experience of physical illness: existential loss, embodiment, and limits on the capacity to work and on their sense of agency. The experiences of physical illness, mental health difficulties, and social stressors were described as mutually reinforcing. In mental health intakes, patients attributed meaning to the negative effects of physical health problems in relation to mental health functioning and social stressors. Decreased capacity to work was a particularly salient concern. The complexity of these patient-provider interactions may best be captured by a sociosomatic formulation that addresses the meaning of physical and mental illness in relation to social stressors. © The Author(s) 2016.

The Kantian element in the Copenhagen interpretation of quantum mechanics

NASA Astrophysics Data System (ADS)

Cale, David Lee

In Quantum Physics and the Philosophical Tradition, Aage Petersen makes the troubling claim that the entirety of the tradition of Western philosophy is "deconstructed" by quantum mechanics. This viewpoint applies, especially, to the relationship between Kantian philosophy and quantum theory. It is generally accepted that quantum mechanics, in its Copenhagen interpretation, has destroyed all validity for the classical belief in a deterministic underlying reality, a belief sustained throughout the nineteenth century through a philosophical ground in Kant's critical philosophy. This dissertation takes on the daunting task of determining what, if any, relationship can be had between contemporary physics and Kantian philosophy. It begins with a historical review of the challenges posed for Kant's arguments and proposed solutions, especially those offered by Cassirer. It then turns to the task of providing the Western philosophical tradition with an interpretation apart from Petersen's, which sees it as concerned only with the problem of being. The offered solution is the suggestion that Western philosophy be understood as a struggle, between epistemological and ontological perspectives, to provide a context for the various descriptions of nature provided by human scientific progress. Kant's philosophy is then interpreted as an effort to provide Newtonian physics with a valid context in the face of Hume's skepticism. The finding is that Kant was the first to suggest that an object does not acquire the spatio-temporal properties used in its physical description until introduced to an observer. The dissertation concludes that the authors of the Copenhagen interpretation were essentially engaged in Kant's enterprise through their attempt to provide an observer based context for the spatio-temporal descriptive principles used in the physics of their time.

From Feynman rules to conserved quantum numbers, I

NASA Astrophysics Data System (ADS)

Nogueira, P.

2017-05-01

In the context of Quantum Field Theory (QFT) there is often the need to find sets of graph-like diagrams (the so-called Feynman diagrams) for a given physical model. If negative, the answer to the related problem 'Are there any diagrams with this set of external fields?' may settle certain physical questions at once. Here the latter problem is formulated in terms of a system of linear diophantine equations derived from the Lagrangian density, from which necessary conditions for the existence of the required diagrams may be obtained. Those conditions are equalities that look like either linear diophantine equations or linear modular (i.e. congruence) equations, and may be found by means of fairly simple algorithms that involve integer computations. The diophantine equations so obtained represent (particle) number conservation rules, and are related to the conserved (additive) quantum numbers that may be assigned to the fields of the model.

Brain Dynamics: Methodological Issues and Applications in Psychiatric and Neurologic Diseases

NASA Astrophysics Data System (ADS)

Pezard, Laurent

The human brain is a complex dynamical system generating the EEG signal. Numerical methods developed to study complex physical dynamics have been used to characterize EEG since the mid-eighties. This endeavor raised several issues related to the specificity of EEG. Firstly, theoretical and methodological studies should address the major differences between the dynamics of the human brain and physical systems. Secondly, this approach of EEG signal should prove to be relevant for dealing with physiological or clinical problems. A set of studies performed in our group is presented here within the context of these two problematic aspects. After the discussion of methodological drawbacks, we review numerical simulations related to the high dimension and spatial extension of brain dynamics. Experimental studies in neurologic and psychiatric disease are then presented. We conclude that if it is now clear that brain dynamics changes in relation with clinical situations, methodological problems remain largely unsolved.

Military sexual trauma research: a proposed agenda.

PubMed

Allard, Carolyn B; Nunnink, Sarah; Gregory, Amber M; Klest, Bridget; Platt, Melissa

2011-01-01

Military sexual trauma (MST) is a widespread problem associated with negative psychological and physical health problems. This article presents the current state of MST research and highlights specific areas in need of more focused study. Areas that have produced the greatest body of knowledge include MST prevalence and psychological and physical health correlates. We propose a research agenda based on gaps noted in our research review and empirical and theoretical evidence of issues relevant to but not studied directly in MST populations. We present evidence that MST is qualitatively distinct from other forms of sexual maltreatment in terms of its relational and vocational context as well as the severity of associated psychological distress, examine underexplored gender and sexual issues in MST, and discuss the lack of treatment and prevention studies specific to MST. Specific recommendations are made throughout in an attempt to guide and advance the field.

Tree diversity and species identity effects on soil fungi, protists and animals are context dependent

PubMed Central

Tedersoo, Leho; Bahram, Mohammad; Cajthaml, Tomáš; Põlme, Sergei; Hiiesalu, Indrek; Anslan, Sten; Harend, Helery; Buegger, Franz; Pritsch, Karin; Koricheva, Julia; Abarenkov, Kessy

2016-01-01

Plant species richness and the presence of certain influential species (sampling effect) drive the stability and functionality of ecosystems as well as primary production and biomass of consumers. However, little is known about these floristic effects on richness and community composition of soil biota in forest habitats owing to methodological constraints. We developed a DNA metabarcoding approach to identify the major eukaryote groups directly from soil with roughly species-level resolution. Using this method, we examined the effects of tree diversity and individual tree species on soil microbial biomass and taxonomic richness of soil biota in two experimental study systems in Finland and Estonia and accounted for edaphic variables and spatial autocorrelation. Our analyses revealed that the effects of tree diversity and individual species on soil biota are largely context dependent. Multiple regression and structural equation modelling suggested that biomass, soil pH, nutrients and tree species directly affect richness of different taxonomic groups. The community composition of most soil organisms was strongly correlated due to similar response to environmental predictors rather than causal relationships. On a local scale, soil resources and tree species have stronger effect on diversity of soil biota than tree species richness per se. PMID:26172210

Tree diversity and species identity effects on soil fungi, protists and animals are context dependent.

PubMed

Tedersoo, Leho; Bahram, Mohammad; Cajthaml, Tomáš; Põlme, Sergei; Hiiesalu, Indrek; Anslan, Sten; Harend, Helery; Buegger, Franz; Pritsch, Karin; Koricheva, Julia; Abarenkov, Kessy

2016-02-01

Plant species richness and the presence of certain influential species (sampling effect) drive the stability and functionality of ecosystems as well as primary production and biomass of consumers. However, little is known about these floristic effects on richness and community composition of soil biota in forest habitats owing to methodological constraints. We developed a DNA metabarcoding approach to identify the major eukaryote groups directly from soil with roughly species-level resolution. Using this method, we examined the effects of tree diversity and individual tree species on soil microbial biomass and taxonomic richness of soil biota in two experimental study systems in Finland and Estonia and accounted for edaphic variables and spatial autocorrelation. Our analyses revealed that the effects of tree diversity and individual species on soil biota are largely context dependent. Multiple regression and structural equation modelling suggested that biomass, soil pH, nutrients and tree species directly affect richness of different taxonomic groups. The community composition of most soil organisms was strongly correlated due to similar response to environmental predictors rather than causal relationships. On a local scale, soil resources and tree species have stronger effect on diversity of soil biota than tree species richness per se.

Is the survival-processing memory advantage due to richness of encoding?

PubMed

Röer, Jan P; Bell, Raoul; Buchner, Axel

2013-07-01

Memory for words rated according to their relevance in a grassland survival context is exceptionally good. According to Nairne, Thompson, and Pandeirada's (2007) evolutionary-based explanation, natural selection processes have tuned the human memory system to prioritize the processing of fitness-relevant information. The survival-processing memory advantage has been replicated numerous times, but very little is known about the proximate mechanisms behind it. The richness-of-encoding hypothesis (Kroneisen & Erdfelder, 2011) implies that rating the usefulness of items in a survival context leads to the generation of a large number of ideas that may be used as retrieval cues at test to boost recall. In Experiment 1, the typical survival-processing recall advantage was obtained when words were rated according to their usefulness in 1 of 3 fictional contexts. In Experiment 2, participants were asked to write down any ideas that came to mind when thinking about the usefulness of the words. Consistent with the richness-of-encoding hypothesis, participants generated more ideas in the survival condition than in the fitness-irrelevant control conditions. In Experiment 3, participants generated more ideas for congruent than for incongruent words, demonstrating that the richness-of-encoding hypothesis can also account for the previously obtained congruency effect on recall (Butler, Kang, & Roediger, 2009). In both experiments the number of ideas written down predicted future recall performance well. Our results provide further evidence for the assumption that richness of encoding is an important proximate mechanism involved in memory performance in the survival-processing paradigm. PsycINFO Database Record (c) 2013 APA, all rights reserved.

SEACAS Theory Manuals: Part 1. Problem Formulation in Nonlinear Solid Mechancis

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

Attaway, S.W.; Laursen, T.A.; Zadoks, R.I.

1998-08-01

This report gives an introduction to the basic concepts and principles involved in the formulation of nonlinear problems in solid mechanics. By way of motivation, the discussion begins with a survey of some of the important sources of nonlinearity in solid mechanics applications, using wherever possible simple one dimensional idealizations to demonstrate the physical concepts. This discussion is then generalized by presenting generic statements of initial/boundary value problems in solid mechanics, using linear elasticity as a template and encompassing such ideas as strong and weak forms of boundary value problems, boundary and initial conditions, and dynamic and quasistatic idealizations. Themore » notational framework used for the linearized problem is then extended to account for finite deformation of possibly inelastic solids, providing the context for the descriptions of nonlinear continuum mechanics, constitutive modeling, and finite element technology given in three companion reports.« less

Resource Prospector, the Decadal Survey and the Scientific Context for the Exploration of the Moon

NASA Technical Reports Server (NTRS)

Elphic, R. C.; Colaprete, A.; Andrews, D. R.

2017-01-01

The Inner Planets Panel of the Planetary Exploration Decadal Survey defined several science questions related to the origins, emplacement, and sequestration of lunar polar volatiles: 1. What is the lateral and vertical distribution of the volatile deposits? 2. What is the chemical composition and variability of polar volatiles? 3. What is the isotopic composition of the volatiles? 4. What is the physical form of the volatiles? 5. What is the rate of the current volatile deposition? A mission concept study, the Lunar Polar Volatiles Explorer (LPVE), defined a approximately $1B New Frontiers mission to address these questions. The NAS/NRC report, 'Scientific Context for the Exploration of the Moon' identified he lunar poles as special environments with important implications. It put forth the following goals: Science Goal 4a-Determine the compositional state (elemental, isotopic, mineralogic) and compositional distribution (lateral and depth) of the volatile component in lunar polar regions. Science Goal 4b-Determine the source(s) for lunar polar volatiles. Science Goal 4c-Understand the transport, retention, alteration, and loss processes that operate on volatile materials at permanently shaded lunar regions. Science Goal 4d-Understand the physical properties of the extremely cold (and possibly volatile rich) polar regolith. Science Goal 4e-Determine what the cold polar regolith reveals about the ancient solar environment.

The International Postal Network and Other Global Flows as Proxies for National Wellbeing.

PubMed

Hristova, Desislava; Rutherford, Alex; Anson, Jose; Luengo-Oroz, Miguel; Mascolo, Cecilia

2016-01-01

The digital exhaust left by flows of physical and digital commodities provides a rich measure of the nature, strength and significance of relationships between countries in the global network. With this work, we examine how these traces and the network structure can reveal the socioeconomic profile of different countries. We take into account multiple international networks of physical and digital flows, including the previously unexplored international postal network. By measuring the position of each country in the Trade, Postal, Migration, International Flights, IP and Digital Communications networks, we are able to build proxies for a number of crucial socioeconomic indicators such as GDP per capita and the Human Development Index ranking along with twelve other indicators used as benchmarks of national well-being by the United Nations and other international organisations. In this context, we have also proposed and evaluated a global connectivity degree measure applying multiplex theory across the six networks that accounts for the strength of relationships between countries. We conclude by showing how countries with shared community membership over multiple networks have similar socioeconomic profiles. Combining multiple flow data sources can help understand the forces which drive economic activity on a global level. Such an ability to infer proxy indicators in a context of incomplete information is extremely timely in light of recent discussions on measurement of indicators relevant to the Sustainable Development Goals.

The International Postal Network and Other Global Flows as Proxies for National Wellbeing

PubMed Central

Rutherford, Alex; Anson, Jose; Luengo-Oroz, Miguel; Mascolo, Cecilia

2016-01-01

The digital exhaust left by flows of physical and digital commodities provides a rich measure of the nature, strength and significance of relationships between countries in the global network. With this work, we examine how these traces and the network structure can reveal the socioeconomic profile of different countries. We take into account multiple international networks of physical and digital flows, including the previously unexplored international postal network. By measuring the position of each country in the Trade, Postal, Migration, International Flights, IP and Digital Communications networks, we are able to build proxies for a number of crucial socioeconomic indicators such as GDP per capita and the Human Development Index ranking along with twelve other indicators used as benchmarks of national well-being by the United Nations and other international organisations. In this context, we have also proposed and evaluated a global connectivity degree measure applying multiplex theory across the six networks that accounts for the strength of relationships between countries. We conclude by showing how countries with shared community membership over multiple networks have similar socioeconomic profiles. Combining multiple flow data sources can help understand the forces which drive economic activity on a global level. Such an ability to infer proxy indicators in a context of incomplete information is extremely timely in light of recent discussions on measurement of indicators relevant to the Sustainable Development Goals. PMID:27248142

Cocoa antioxidants and cardiovascular health.

PubMed

Keen, Carl L; Holt, Roberta R; Oteiza, Patricia I; Fraga, César G; Schmitz, Harold H

2005-01-01

An increasing body of epidemiologic evidence supports the concept that diets rich in fruits and vegetables can promote health and attenuate, or delay, the onset of various diseases. Epidemiologic data support the idea that these health benefits are causally linked to the consumption of certain flavonoids present in fruit and vegetables. In the context of cardiovascular health, a particular group of flavonoids, namely, the flavan-3-ols (flavanols), has received attention. Flavanol-rich, plant-derived foods and beverages include wine, tea, and various fruits and berries, as well as cocoa and cocoa products. Numerous dietary intervention studies in humans and animals indicate that flavanol-rich foods and beverages might exert cardioprotective effects with respect to vascular function and platelet reactivity. This review discusses the bioactivity of flavanols in the context of cardiovascular health, with respect to their bioavailability, their antioxidant properties, and their vascular effects.

Effects of Videodisc Macrocontexts on Comprehension and Composition of Causally Coherent Stories.

ERIC Educational Resources Information Center

Risko, Victoria J.; And Others

A study determined whether instruction on story elements within rich contexts can increase students' understanding of the characters' traits and motives, their comprehension of stories, and their ability to write causally coherent stories. Instruction was organized around an "anchor" (a story rich with embedded information presented on…

A social ecological assessment of physical activity among urban adolescents.

PubMed

Yan, Alice Fang; Voorhees, Carolyn C; Beck, Kenneth H; Wang, Min Qi

2014-05-01

To examine the physical, social and temporal contexts of physical activity, as well as sex variations of the associations among 314 urban adolescents. Three-day physical activity recall measured contextual information of physical activities. Logistic regressions and generalized estimating equation models examined associations among physical activity types and contexts, and sex differences. Active transportation was the most common physical activity. Home/neighborhood and school were the most common physical activity locations. School was the main location for organized physical activity. Boys spent more time on recreational physical activity, regardless of the social context, compared to girls. The average physical activity level was significantly lower for girls than for boys after school. Physical activity promotion interventions need to target physical activity environments and social contexts in a sex-specific manner.

Physics Teachers' Education (PTE): Problems and Challenges

NASA Astrophysics Data System (ADS)

Sassi, Elena; Michelini, Marisa

A vast majority of the research results acknowledge the crucial role of teacher's education, as a vital tool in enhancing the quality of physics education. The projects like PISA, ROSE and TIMMS showcase the impact of teacher's education as a qualitative improvement in the physics learning environment. In Physics Education Research (PER), the impact of teacher's education had been addressed for the its role in the enhancement of positive interest among the students. The current world-wide state of the art characterizes a large variety of boundary conditions, traditions and practices that are being followed. In our present context, we foucus and discuss on the multidimensional challanges such as competencies needed, degrees required, problems encountered, support to be provided and the basic pre-requirements of Teacher's education for the secondary schools. We present some of the teaching methods and practices followed in coherent with, both, the Student centered and open learning environments along with some of the useful didactical indicators. Also, we potray a couple of research-based examples successfully experimented in Italy. Finally we propose some useful recommendations along with the criteria to be followed in the teachers education for the overall improvement.

Methods of Mathematical and Computational Physics for Industry, Science, and Technology

NASA Astrophysics Data System (ADS)

Melnik, Roderick V. N.; Voss, Frands

2006-11-01

Many industrial problems provide scientists with important and challenging problems that need to be solved today rather than tomorrow. The key role of mathematical physics, modelling, and computational methodologies in addressing such problems continues to increase. Science has never been exogenous to applied research. Gigantic ships and steam engines, repeating catapult of Dionysius and the Antikythera `computer' invented around 80BC are just a few examples demonstrating a profound link between theoretical and applied science in the ancient world. Nowadays, many industrial problems are typically approached by groups of researchers who are working as a team bringing their expertise to the success of the entire enterprise. Since the late 1960s several groups of European mathematicians and scientists have started organizing regular meetings, seeking new challenges from industry and contributing to the solution of important industrial problems. In particular, this often took the format of week-long workshops originally initiated by the Oxford Study Groups with Industry in 1968. Such workshops are now held in many European countries (typically under the auspices of the European Study Groups with Industry - ESGI), as well as in Australia, Canada, the United States, and other countries around the world. Problems given by industrial partners are sometimes very difficult to complete within a week. However, during a week of brainstorming activities these problems inevitably stimulate developing fruitful new ideas, new approaches, and new collaborations. At the same time, there are cases where as soon as the problem is formulated mathematically, it is relatively easy to solve. Hence, putting the industrial problem into a mathematical framework, based on physical laws, often provides a key element to the success. In addition to this important first step, the value in such cases is the real, practical applicability of the results obtained for an industrial partner who presents the problem. Under both outlined scenarios, scientists and mathematicians are provided with an opportunity to challenge themselves with real-world problems and to work together in a team on important industrial issues. This issue is a result of selected contributions by participants of the meeting that took place in the Sønderborg area of Denmark, one of the most important centers for information technology, telecommunication and electronics in the country. The meeting was hosted by the University of Southern Denmark in a picturesque area of Southern Jutland. It brought together about 65 participants, among whom were professional mathematicians, engineers, physicists, and industrial participants. The meeting was a truly international one, with delegates from four major Danish Universities, the UK, Norway, Italy, Czech Republic, Turkey, China, Germany, Latvia, Canada, the United States, and Finland. Five challenging projects were presented by leading industrial companies, including Grundfos, Danfoss Industrial Control, Unisensor, and Danfoss Flow Division (now Siemens). The meeting featured also the Mathematics for Industry Workshop with several distinguished international speakers. This volume of Journal of Physics: Conference Series on `Methods of Mathematical and Computational Physics for Industry, Science, and Technology' contains contributions from some of the participants of the workshop as well as the papers produced as a result of collaborative efforts with the above mentioned industrial companies. We would like to thank all authors and participants for their contributions and for bearing with us during the review process and preparation of this issue. We thank also all our referees for their timely and detailed reports. The publication of the proceedings of this meeting in Denmark was delayed due to problems with a previous publisher. We are very grateful that Journal of Physics: Conference Series kindly agreed to publish the proceedings rapidly at this late stage. As industrial problems become increasingly multidisciplinary, their successful solutions are often contingent on effective collaborative efforts between scientists, mathematicians, industrialists, and engineers. This volume has provided several examples of such collaborative efforts in the context of real-world industrial problems along with the analysis of important physics-based mathematical models applicable in a range of industrial contexts. Roderick V N Melnik, Professor of Mathematical Modelling, Syddansk Universitet (Denmark) and Professor and Canada Research Chair, Wilfrid Laurier University, Waterloo, Canada E-mail: rmelnik@wlu.ca Frands Voss, Director of the Mads Clausen Institute, Syddansk Universitet (Denmark)

Maternal and paternal physical abuse: Unique and joint associations with child behavioral problems.

PubMed

Cui, Naixue; Deatrick, Janet A; Liu, Jianghong

2018-02-01

Although there is a substantial amount of literature documenting the relationship between child abuse and behavioral problems in China, there is, on the other hand, a limited number of studies on the joint and unique associations of maternal and paternal physical abuse with child behaviors within the Chinese context. The present study, using the family systems theory as the theoretical framework, aims to examine these joint and the unique associations of maternal and paternal physical abuse with externalizing and internalizing behaviors among a community sample of Chinese children. A total of 296 children (54.7% boys, mean age 12.31±0.56years) from two-parent families participated in the study, and they reported their physical abuse experience by their mother and father in the previous year using the Chinese version of the Parent-Child Conflict Tactics Scale. Participants, using the Youth Self Report, reported personal externalizing and internalizing behaviors, and, similarly, their mothers, using the Child Behavior Checklist, assessed children's externalizing and internalizing behaviors. Linear mixed effect models with random intercept and slope were used to examine the joint and unique associations of maternal and paternal physical abuse with child externalizing and internalizing behaviors. Results revealed that physically abused children were more likely to be simultaneously abused by both mothers and fathers. Furthermore, when compared with their non-abused counterparts, children with physical abuse that was carried out solely by mothers (externalizing behaviors: β=6.71, 95% CI=2.45-10.98, p<0.01; internalizing behaviors: β=4.52, 95% CI=0.37-8.66, p<0.05) or by both mothers and fathers (externalizing behaviors: β=4.52, 95% CI=1.80-7.24, p<0.001; internalizing behaviors: β=2.98, 95% CI=0.34-5.61, p<0.05) reported more externalizing and internalizing behaviors. Externalizing and internalizing behaviors of children who were physically abused solely by fathers did not significantly differ from those of their non-abused counterparts, which may result from the small sample size. The present findings suggest that maternal physical abuse may have a dominant and unique association with child behaviors, regardless of whether paternal physical abuse occurs within the family. Implications for future research and practice within the Chinese context regarding the subject of child behaviors and parental abuse are discussed. Copyright © 2017. Published by Elsevier Ltd.

A unified model of avian species richness on islands and continents.

PubMed

Kalmar, Attila; Currie, David J

2007-05-01

How many species in a given taxon should be found in a delimited area in a specified place in the world? Some recent literature suggests that the answer to this question depends strongly on the geographical, evolutionary, and ecological context. For example, current theory suggests that species accumulate as a function of area differently on continents and islands. Species richness-climate relationships have been examined separately on continents and on islands. This study tests the hypotheses that (1) the functional relationship between richness and climate is the same on continents and islands; (2) the species-area slope depends on distance-based isolation; (3) species-area relationships differ among land bridge islands, oceanic islands, and continents; (4) richness differs among biogeographic regions independently of climate and isolation. We related bird species numbers in a worldwide sample of 240 continental parcels and 346 islands to several environmental variables. We found that breeding bird richness varies similarly on islands and on continents as a function of mean annual temperature, an area x precipitation interaction, and the distance separating insular samples from the nearest continent (R2 = 0.86). Most studies to date have postulated that the slope of the species-area relationship depends upon isolation. In contrast, we found no such interaction. A richness-environment relationship derived using Old World sites accurately predicts patterns of richness in the New World and vice versa (R2 = 0.85). Our results suggest that most of the global variation in richness is not strongly context-specific; rather, it reflects a small number of general environmental constraints operating on both continents and islands.

Climatic and Catchment-Scale Predictors of Chinese Stream Insect Richness Differ between Taxonomic Groups

PubMed Central

Tonkin, Jonathan D.; Shah, Deep Narayan; Kuemmerlen, Mathias; Li, Fengqing; Cai, Qinghua; Haase, Peter; Jähnig, Sonja C.

2015-01-01

Little work has been done on large-scale patterns of stream insect richness in China. We explored the influence of climatic and catchment-scale factors on stream insect (Ephemeroptera, Plecoptera, Trichoptera; EPT) richness across mid-latitude China. We assessed the predictive ability of climatic, catchment land cover and physical structure variables on genus richness of EPT, both individually and combined, in 80 mid-latitude Chinese streams, spanning a 3899-m altitudinal gradient. We performed analyses using boosted regression trees and explored the nature of their influence on richness patterns. The relative importance of climate, land cover, and physical factors on stream insect richness varied considerably between the three orders, and while important for Ephemeroptera and Plecoptera, latitude did not improve model fit for any of the groups. EPT richness was linked with areas comprising high forest cover, elevation and slope, large catchments and low temperatures. Ephemeroptera favoured areas with high forest cover, medium-to-large catchment sizes, high temperature seasonality, and low potential evapotranspiration. Plecoptera richness was linked with low temperature seasonality and annual mean, and high slope, elevation and warm-season rainfall. Finally, Trichoptera favoured high elevation areas, with high forest cover, and low mean annual temperature, seasonality and aridity. Our findings highlight the variable role that catchment land cover, physical properties and climatic influences have on stream insect richness. This is one of the first studies of its kind in Chinese streams, thus we set the scene for more in-depth assessments of stream insect richness across broader spatial scales in China, but stress the importance of improving data availability and consistency through time. PMID:25909190

Physical inactivity: the "Cinderella" risk factor for noncommunicable disease prevention.

PubMed

Bull, Fiona C; Bauman, Adrian E

2011-08-01

There is strong evidence demonstrating the direct and indirect pathways by which physical activity prevents many of the major noncommunicable diseases (NCD) responsible for premature death and disability. Physical inactivity was identified as the 4th leading risk factor for the prevention of NCD, preceded only by tobacco use, hypertension, and high blood glucose levels, and accounting for more than 3 million preventable deaths globally in 2010. Physical inactivity is a global public health priority but, in most countries, this has not yet resulted in widespread recognition nor specific physical activity-related policy action at the necessary scale. Instead, physical inactivity could be described as the Cinderella of NCD risk factors, defined as "poverty of policy attention and resourcing proportionate to its importance." The pressing question is "Why is this so?" The authors identify and discuss 8 possible explanations and the need for more effective communication on the importance of physical activity in the NCD prevention context. Although not all of the issues identified will be relevant for any 1 country, it is likely that at different times and in different combinations these 8 problems continue to delay national-level progress on addressing physical inactivity in many countries. The authors confirm that there is sufficient evidence to act, and that much better use of well-planned, coherent communication strategies are needed in most countries and at the international level. Significant opportunities exist. The Toronto Charter on Physical Activity and the Seven Investments that Work are 2 useful tools to support increased advocacy on physical activity within and beyond the context of the crucial 2011 UN High-Level Meeting on NCDs.

Incoherent Scatter Plasma Lines: Observations and Applications

NASA Astrophysics Data System (ADS)

Akbari, Hassanali; Bhatt, Asti; La Hoz, Cesar; Semeter, Joshua L.

2017-10-01

Space plasmas are host to the electrostatic Langmuir waves and a rich range of processes associated with them. Many of such processes that are of interest in micro-scale plasma physics and magnetosphere-ionosphere physics are open to investigation via incoherent scatter plasma lines—i.e., a pair of resonant peaks in the incoherent scatter radar (ISR) spectrum, symmetrically displaced from the radar transmitting frequency by about the plasma frequency, as the signature of Langmuir waves in the ISR spectrum. There now exists a large body of literature devoted to the investigation of a number of topics in ionospheric physics via plasma line theory and observation. It is the goal of this work to provide a comprehensive review of this literature, from the early theoretical works on oscillations in magnetized plasma to the recent advances in plasma line measurements and applications. This review includes detailed theoretical discussions on the intensity and frequency displacement of plasma lines. It reviews the experimental observations of plasma lines enhanced by various sources of energy and discusses the implications of the observations in the context of ionospheric physics. The review also covers the practical aspects of plasma line measurements, from measurement techniques to the applications of plasma lines in estimating the bulk parameters of the ionosphere.

An evolving perspective on physical activity counselling by medical professionals.

PubMed

McPhail, Steven; Schippers, Mandy

2012-04-23

Physical inactivity is a modifiable risk factor for many chronic conditions and a leading cause of premature mortality. An increasing proportion of adults worldwide are not engaging in a level of physical activity sufficient to prevent or alleviate these adverse effects. Medical professionals have been identified as potentially powerful sources of influence for those who do not meet minimum physical activity guidelines. Health professionals are respected and expected sources of advice and they reach a large and relevant proportion of the population. Despite this potential, health professionals are not routinely practicing physical activity promotion. Medical professionals experience several known barriers to physical activity promotion including lack of time and lack of perceived efficacy in changing physical activity behaviour in patients. Furthermore, evidence for effective physical activity promotion by medical professionals is inconclusive. To address these problems, new approaches to physical activity promotion are being proposed. These include collaborating with community based physical activity behaviour change interventions, preparing patients for effective brief counselling during a consultation with the medical professional, and use of interactive behaviour change technology. It is important that we recognise the latent risk of physical inactivity among patients presenting in clinical settings. Preparation for improving patient physical activity behaviours should commence before the consultation and may include physical activity screening. Medical professionals should also identify suitable community interventions to which they can refer physically inactive patients. Outsourcing the majority of a comprehensive physical activity intervention to community based interventions will reduce the required clinical consultation time for addressing the issue with each patient. Priorities for future research include investigating ways to promote successful referrals and subsequent engagement in comprehensive community support programs to increase physical activity levels of inactive patients. Additionally, future clinical trials of physical activity interventions should be evaluated in the context of a broader framework of outcomes to inform a systematic consideration of broad strengths and weaknesses regarding not only efficacy but cost-effectiveness and likelihood of successful translation of interventions to clinical contexts.

Province-Level Income Inequality and Health Outcomes in Canadian Adolescents

PubMed Central

McGrath, Jennifer J.

2015-01-01

Objective To examine the effects of provincial income inequality (disparity between rich and poor), independent of provincial income and family socioeconomic status, on multiple adolescent health outcomes. Methods Participants (aged 12–17 years; N = 11,899) were from the Canadian National Longitudinal Survey of Children and Youth. Parental education, household income, province income inequality, and province mean income were measured. Health outcomes were measured across a number of domains, including self-rated health, mental health, health behaviors, substance use behaviors, and physical health. Results Income inequality was associated with injuries, general physical symptoms, and limiting conditions, but not associated with most adolescent health outcomes and behaviors. Income inequality had a moderating effect on family socioeconomic status for limiting conditions, hyperactivity/inattention, and conduct problems, but not for other outcomes. Conclusions Province-level income inequality was associated with some physical and mental health outcomes in adolescents, which has research and policy implications for this age-group. PMID:25324533

Molecular deconstruction, detection, and computational prediction of microenvironment-modulated cellular responses to cancer therapeutics.

PubMed

Labarge, Mark A; Parvin, Bahram; Lorens, James B

2014-04-01

The field of bioengineering has pioneered the application of new precision fabrication technologies to model the different geometric, physical or molecular components of tissue microenvironments on solid-state substrata. Tissue engineering approaches building on these advances are used to assemble multicellular mimetic-tissues where cells reside within defined spatial contexts. The functional responses of cells in fabricated microenvironments have revealed a rich interplay between the genome and extracellular effectors in determining cellular phenotypes and in a number of cases have revealed the dominance of microenvironment over genotype. Precision bioengineered substrata are limited to a few aspects, whereas cell/tissue-derived microenvironments have many undefined components. Thus, introducing a computational module may serve to integrate these types of platforms to create reasonable models of drug responses in human tissues. This review discusses how combinatorial microenvironment microarrays and other biomimetic microenvironments have revealed emergent properties of cells in particular microenvironmental contexts, the platforms that can measure phenotypic changes within those contexts, and the computational tools that can unify the microenvironment-imposed functional phenotypes with underlying constellations of proteins and genes. Ultimately we propose that a merger of these technologies will enable more accurate pre-clinical drug discovery. Copyright © 2014 Elsevier B.V. All rights reserved.

Comparison of university students' understanding of graphs in different contexts

NASA Astrophysics Data System (ADS)

Planinic, Maja; Ivanjek, Lana; Susac, Ana; Milin-Sipus, Zeljka

2013-12-01

This study investigates university students’ understanding of graphs in three different domains: mathematics, physics (kinematics), and contexts other than physics. Eight sets of parallel mathematics, physics, and other context questions about graphs were developed. A test consisting of these eight sets of questions (24 questions in all) was administered to 385 first year students at University of Zagreb who were either prospective physics or mathematics teachers or prospective physicists or mathematicians. Rasch analysis of data was conducted and linear measures for item difficulties were obtained. Average difficulties of items in three domains (mathematics, physics, and other contexts) and over two concepts (graph slope, area under the graph) were computed and compared. Analysis suggests that the variation of average difficulty among the three domains is much smaller for the concept of graph slope than for the concept of area under the graph. Most of the slope items are very close in difficulty, suggesting that students who have developed sufficient understanding of graph slope in mathematics are generally able to transfer it almost equally successfully to other contexts. A large difference was found between the difficulty of the concept of area under the graph in physics and other contexts on one side and mathematics on the other side. Comparison of average difficulty of the three domains suggests that mathematics without context is the easiest domain for students. Adding either physics or other context to mathematical items generally seems to increase item difficulty. No significant difference was found between the average item difficulty in physics and contexts other than physics, suggesting that physics (kinematics) remains a difficult context for most students despite the received instruction on kinematics in high school.

Continuum-Kinetic Models and Numerical Methods for Multiphase Applications

NASA Astrophysics Data System (ADS)

Nault, Isaac Michael

This thesis presents a continuum-kinetic approach for modeling general problems in multiphase solid mechanics. In this context, a continuum model refers to any model, typically on the macro-scale, in which continuous state variables are used to capture the most important physics: conservation of mass, momentum, and energy. A kinetic model refers to any model, typically on the meso-scale, which captures the statistical motion and evolution of microscopic entitites. Multiphase phenomena usually involve non-negligible micro or meso-scopic effects at the interfaces between phases. The approach developed in the thesis attempts to combine the computational performance benefits of a continuum model with the physical accuracy of a kinetic model when applied to a multiphase problem. The approach is applied to modeling a single particle impact in Cold Spray, an engineering process that intimately involves the interaction of crystal grains with high-magnitude elastic waves. Such a situation could be classified a multiphase application due to the discrete nature of grains on the spatial scale of the problem. For this application, a hyper elasto-plastic model is solved by a finite volume method with approximate Riemann solver. The results of this model are compared for two types of plastic closure: a phenomenological macro-scale constitutive law, and a physics-based meso-scale Crystal Plasticity model.

Providing Effective Speech-Language Pathology Group Treatment in the Comprehensive Inpatient Rehabilitation Setting.

PubMed

Baron, Christine; Holcombe, Molly; van der Stelt, Candace

2018-02-01

Group treatment is an integral part of speech-language pathology (SLP) practice. The majority of SLP literature concerns group treatment provided in outpatient settings. This article describes the goals, procedures, and benefits of providing quality SLP group therapy in the comprehensive inpatient rehabilitation (CIR) setting. Effective CIR groups must be designed with attention to type and severity of communication impairment, as well physical stamina of group members. Group leaders need to target individualized patient goals while creating a challenging, complex, and dynamic group context that supports participation by all group members. Direct patient-to-patient interaction is fostered as much as possible. Peer feedback supports goal acquisition by fellow group members. The rich, complex group context fosters improved insight, initiation, social connectedness, and generalization of communication skills. Group treatment provides a unique type of treatment not easily replicated with individual treatment. SLP group treatment in a CIR is an essential component of an intensive, high-quality program. Continued advocacy for group therapy provision and research into its efficacy and effectiveness are warranted. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Geological and taphonomic context for the new hominin species Homo naledi from the Dinaledi Chamber, South Africa

PubMed Central

Dirks, Paul HGM; Berger, Lee R; Roberts, Eric M; Kramers, Jan D; Hawks, John; Randolph-Quinney, Patrick S; Elliott, Marina; Musiba, Charles M; Churchill, Steven E; de Ruiter, Darryl J; Schmid, Peter; Backwell, Lucinda R; Belyanin, Georgy A; Boshoff, Pedro; Hunter, K Lindsay; Feuerriegel, Elen M; Gurtov, Alia; Harrison, James du G; Hunter, Rick; Kruger, Ashley; Morris, Hannah; Makhubela, Tebogo V; Peixotto, Becca; Tucker, Steven

2015-01-01

We describe the physical context of the Dinaledi Chamber within the Rising Star cave, South Africa, which contains the fossils of Homo naledi. Approximately 1550 specimens of hominin remains have been recovered from at least 15 individuals, representing a small portion of the total fossil content. Macro-vertebrate fossils are exclusively H. naledi, and occur within clay-rich sediments derived from in situ weathering, and exogenous clay and silt, which entered the chamber through fractures that prevented passage of coarser-grained material. The chamber was always in the dark zone, and not accessible to non-hominins. Bone taphonomy indicates that hominin individuals reached the chamber complete, with disarticulation occurring during/after deposition. Hominins accumulated over time as older laminated mudstone units and sediment along the cave floor were eroded. Preliminary evidence is consistent with deliberate body disposal in a single location, by a hominin species other than Homo sapiens, at an as-yet unknown date. DOI: http://dx.doi.org/10.7554/eLife.09561.001 PMID:26354289

Dispersive shock waves and modulation theory

NASA Astrophysics Data System (ADS)

El, G. A.; Hoefer, M. A.

2016-10-01

There is growing physical and mathematical interest in the hydrodynamics of dissipationless/dispersive media. Since G.B. Whitham's seminal publication fifty years ago that ushered in the mathematical study of dispersive hydrodynamics, there has been a significant body of work in this area. However, there has been no comprehensive survey of the field of dispersive hydrodynamics. Utilizing Whitham's averaging theory as the primary mathematical tool, we review the rich mathematical developments over the past fifty years with an emphasis on physical applications. The fundamental, large scale, coherent excitation in dispersive hydrodynamic systems is an expanding, oscillatory dispersive shock wave or DSW. Both the macroscopic and microscopic properties of DSWs are analyzed in detail within the context of the universal, integrable, and foundational models for uni-directional (Korteweg-de Vries equation) and bi-directional (Nonlinear Schrödinger equation) dispersive hydrodynamics. A DSW fitting procedure that does not rely upon integrable structure yet reveals important macroscopic DSW properties is described. DSW theory is then applied to a number of physical applications: superfluids, nonlinear optics, geophysics, and fluid dynamics. Finally, we survey some of the more recent developments including non-classical DSWs, DSW interactions, DSWs in perturbed and inhomogeneous environments, and two-dimensional, oblique DSWs.

Reporting heterogeneity in self-assessed health among elderly Europeans.

PubMed

Pfarr, Christian; Schmid, Andreas; Schneider, Udo

2012-10-05

Self-assessed health (SAH) is a frequently used measure of individuals' health status. It is also prone to reporting heterogeneity. To control for reporting heterogeneity objective measures of true health need to be included in an analysis. The topic becomes even more complex for cross-country comparisons, as many key variables tend to vary strongly across countries, influenced by cultural and institutional differences. This study aims at exploring the key drivers for reporting heterogeneity in SAH in an international context. To this end, country specific effects are accounted for and the objective health measure is concretized, distinguishing effects of mental and physical health conditions. We use panel data from the SHARE-project which provides a rich dataset on the elderly European population. To obtain distinct indicators for physical and mental health conditions two indices are constructed. Finally, to identify potential reporting heterogeneity in SAH a generalized ordered probit model is estimated. We find evidence that in addition to health behaviour, health care utilization, mental and physical health condition as well as country characteristics affect reporting behaviour. We conclude that observed and unobserved heterogeneity play an important role when analysing SAH and have to be taken into account.

Diagnostic Problem-Solving Process in Professional Contexts: Theory and Empirical Investigation in the Context of Car Mechatronics Using Computer-Generated Log-Files

ERIC Educational Resources Information Center

Abele, Stephan

2018-01-01

This article deals with a theory-based investigation of the diagnostic problem-solving process in professional contexts. To begin with, a theory of the diagnostic problem-solving process was developed drawing on findings from different professional contexts. The theory distinguishes between four sub-processes of the diagnostic problem-solving…

Biology meets physics: Reductionism and multi-scale modeling of morphogenesis.

PubMed

Green, Sara; Batterman, Robert

2017-02-01

A common reductionist assumption is that macro-scale behaviors can be described "bottom-up" if only sufficient details about lower-scale processes are available. The view that an "ideal" or "fundamental" physics would be sufficient to explain all macro-scale phenomena has been met with criticism from philosophers of biology. Specifically, scholars have pointed to the impossibility of deducing biological explanations from physical ones, and to the irreducible nature of distinctively biological processes such as gene regulation and evolution. This paper takes a step back in asking whether bottom-up modeling is feasible even when modeling simple physical systems across scales. By comparing examples of multi-scale modeling in physics and biology, we argue that the "tyranny of scales" problem presents a challenge to reductive explanations in both physics and biology. The problem refers to the scale-dependency of physical and biological behaviors that forces researchers to combine different models relying on different scale-specific mathematical strategies and boundary conditions. Analyzing the ways in which different models are combined in multi-scale modeling also has implications for the relation between physics and biology. Contrary to the assumption that physical science approaches provide reductive explanations in biology, we exemplify how inputs from physics often reveal the importance of macro-scale models and explanations. We illustrate this through an examination of the role of biomechanical modeling in developmental biology. In such contexts, the relation between models at different scales and from different disciplines is neither reductive nor completely autonomous, but interdependent. Copyright © 2016 Elsevier Ltd. All rights reserved.

Body image, media, and eating disorders.

PubMed

Derenne, Jennifer L; Beresin, Eugene V

2006-01-01

Eating disorders, including obesity, are a major public health problem today. Throughout history, body image has been determined by various factors, including politics and media. Exposure to mass media (television, movies, magazines, Internet) is correlated with obesity and negative body image, which may lead to disordered eating. The authors attempt to explain the historical context of the problem and explore potential avenues for change. The authors review changes in ideal female body type throughout history, comment on current attitudes toward shape and weight in both men and women, and outline interventions aimed at increasing healthy habits and fostering self-esteem in youth. Throughout history, the ideal of beauty has been difficult to achieve and has been shaped by social context. Current mass media is ubiquitous and powerful, leading to increased body dissatisfaction among both men and women. Parents need to limit children's exposure to media, promote healthy eating and moderate physical activity, and encourage participation in activities that increase mastery and self-esteem. Funding for high-quality, visible advertising campaigns promoting healthy life styles may increase awareness.

Constructing an Interdisciplinary Context for Definition of Life

NASA Astrophysics Data System (ADS)

Tsokolov, S. A.

One of the main problems in understanding life is that that lifecannot be defined as a self-evident phenomenon. Instead, definitions of life inevitably depend on the context: social, ethical, theological, and scientific. Even in a purely scientific context, different scientific disciplines and approaches provide a variety of criteria related to life. My intention is to define life in an interdisciplinary context, where the class of living systems can be presented as a particular case in series of systems: physical, chemical, prebiotic, biotic, ecological, social, cognitive, etc. related by a universal principle. To this end, the first step in establishing general criteria for life is to define the essential features of life processes. The very functional principle of living beings is circular organization (feedback circularity) embedded on different levels of organization: molecular, genetic, cellular, neural, behavioural, mental, and social. Understanding that the degree of system's wholeness, i.e. degree of feedback net integration can serve as a primary parameter, we can in principle construct an interdisciplinary context in which different systems including living beings can be analyzed, defined and compared.

Research-based active-learning instruction in physics

NASA Astrophysics Data System (ADS)

Meltzer, David E.; Thornton, Ronald K.

2013-04-01

The development of research-based active-learning instructional methods in physics has significantly altered the landscape of U.S. physics education during the past 20 years. Based on a recent review [D.E. Meltzer and R.K. Thornton, Am. J. Phys. 80, 478 (2012)], we define these methods as those (1) explicitly based on research in the learning and teaching of physics, (2) that incorporate classroom and/or laboratory activities that require students to express their thinking through speaking, writing, or other actions that go beyond listening and the copying of notes, or execution of prescribed procedures, and (3) that have been tested repeatedly in actual classroom settings and have yielded objective evidence of improved student learning. We describe some key features common to methods in current use. These features focus on (a) recognizing and addressing students' physics ideas, and (b) guiding students to solve problems in realistic physical settings, in novel and diverse contexts, and to justify or explain the reasoning they have used.

The effect of familiarity on perceived interestingness of images

NASA Astrophysics Data System (ADS)

Chu, Sharon Lynn; Fedorovskaya, Elena; Quek, Francis; Snyder, Jeffrey

2013-03-01

We present an exploration of familiarity as a meaningful dimension for the individualized adaptation of media-rich interfaces. In this paper, we investigate in particular the effect of digital images personalized for familiarity on users' perceived interestingness. Two dimensions of familiarity, facial familiarity and familiarity with image context, are manipulated. Our investigation consisted of three studies: the first two address how morphing technology can be used to convey meaningful familiarity, and the third studies the effect of such familiarity on users' sense of interestingness. Four levels of person familiarity varying in degree of person knowledge, and two levels of context familiarity varying in frequency of exposure, were considered: Self, Friend, Celebrity, and Stranger in Familiar and Unfamiliar contexts. Experimental results showed significant main effects of context and person familiarity. Our findings deepen understanding of the critical element of familiarity in HCI and its relationship to the interestingness of images, and can have great impact for the design of media-rich systems.

Semantic Richness and Word Learning in Children with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Gladfelter, Allison; Goffman, Lisa

2018-01-01

Semantically rich learning contexts facilitate semantic, phonological, and articulatory aspects of word learning in children with typical development (TD). However, because children with autism spectrum disorder (ASD) show differences at each of these processing levels, it is unclear whether they will benefit from semantic cues in the same manner…

Stylizing Voices, Stances, and Identities Related to Medium of Education in India

ERIC Educational Resources Information Center

Sandhu, Priti

2015-01-01

This study analyzes the narrative-based interview data of three Indian women to examine the manner in which they utilize stylization to construct identity-rich, ideological stances related to discriminatory discourses of Hindi and English medium education in the linguistically rich, albeit complex, present-day context of India. Stylization is…

Uncertainty Calculations in the First Introductory Physics Laboratory

NASA Astrophysics Data System (ADS)

Rahman, Shafiqur

2005-03-01

Uncertainty in a measured quantity is an integral part of reporting any experimental data. Consequently, Introductory Physics laboratories at many institutions require that students report the values of the quantities being measured as well as their uncertainties. Unfortunately, given that there are three main ways of calculating uncertainty, each suitable for particular situations (which is usually not explained in the lab manual), this is also an area that students feel highly confused about. It frequently generates large number of complaints in the end-of-the semester course evaluations. Students at some institutions are not asked to calculate uncertainty at all, which gives them a fall sense of the nature of experimental data. Taking advantage of the increased sophistication in the use of computers and spreadsheets that students are coming to college with, we have completely restructured our first Introductory Physics Lab to address this problem. Always in the context of a typical lab, we now systematically and sequentially introduce the various ways of calculating uncertainty including a theoretical understanding as opposed to a cookbook approach, all within the context of six three-hour labs. Complaints about the lab in student evaluations have dropped by 80%. * supported by a grant from A. V. Davis Foundation

The Functioning of Context-Based Physics Instruction in Higher Education

ERIC Educational Resources Information Center

Tural, Guner

2014-01-01

The effects of the context-based approach have been discussed in educational settings as one of the innovative instructional approaches. Many countries throughout the world have implemented context-based physics projects or programs to make physics more relevant to students' lives. This paper examined the effects of context-based physics…

Cyber physical systems based on cloud computing and internet of things for energy efficiency

NASA Astrophysics Data System (ADS)

Suciu, George; Butca, Cristina; Suciu, Victor; Cretu, Alexandru; Fratu, Octavian

2016-12-01

Cyber Physical Systems (CPS) and energy efficiency play a major role in the context of industry expansion. Management practices for improving efficiency in the field of energy consumption became a priority of many major industries who are inefficient in terms of exploitation costs. The effort of adopting energy management means in an organization is quite challenging due to the lack of resources and expertise. One major problem consists in the lack of knowledge for energy management and practices. This paper aims to present authors' concept in creating a Cyber Physical Energy System (CPES) that will change organizations' way of consuming energy, by making them aware of their use. The presented concept will consider the security of the whole system and the easy integration with the existing electric network infrastructure.

Dietary behaviour and socioeconomic position: the role of physical activity patterns.

PubMed

Finger, Jonas D; Tylleskär, Thorkild; Lampert, Thomas; Mensink, Gert B M

2013-01-01

The positive association between education level and health outcomes can be partly explained by dietary behaviour. We investigated the associations between education and several indices of food intake and potential influencing factors, placing special emphasis on physical-activity patterns, using a representative sample of the German adult population. The German National Health Interview and Examination Survey 1998 (GNHIES98) involved 7,124 participants aged between 18 and 79. Complete information on the exposure (education) and outcome (nutrition) variables was available for 6,767 persons. The associations between 'education' and indices of 'sugar-rich food', 'fat-rich food', 'fruit-and-vegetable' and 'alcohol' intake were analysed separately for men and women using multivariate logistic regression analysis. Odds ratios (OR) of education level on nutrition outcomes were calculated and adjusted for age, region (former East/West Germany), occupation, income and other influencing factors such as physical activity indicators. Men and women with only a primary education had a more frequent intake of sugar-rich and fat-rich foods and a less frequent intake of fruit and vegetables and alcohol than people with a tertiary education. 'Physical work activity' partly explained the associations between education and sugar-rich food intake. The interference with physical work activity was stronger among men than women. No significant associations between education and energy-dense food intake were observed in the retirement-age group of persons aged 65+ and among persons with low energy expenditure. In Germany, adults with a low level of education report that they consume energy-dense foods more frequently - and fruit and vegetables and alcohol less frequently - than adults with a high education level. High levels of physical work activity among adults with a low education level may partly explain why they consume more energy-dense foods.

NASA Taxonomies for Searching Problem Reports and FMEAs

NASA Technical Reports Server (NTRS)

Malin, Jane T.; Throop, David R.

2006-01-01

Many types of hazard and risk analyses are used during the life cycle of complex systems, including Failure Modes and Effects Analysis (FMEA), Hazard Analysis, Fault Tree and Event Tree Analysis, Probabilistic Risk Assessment, Reliability Analysis and analysis of Problem Reporting and Corrective Action (PRACA) databases. The success of these methods depends on the availability of input data and the analysts knowledge. Standard nomenclature can increase the reusability of hazard, risk and problem data. When nomenclature in the source texts is not standard, taxonomies with mapping words (sets of rough synonyms) can be combined with semantic search to identify items and tag them with metadata based on a rich standard nomenclature. Semantic search uses word meanings in the context of parsed phrases to find matches. The NASA taxonomies provide the word meanings. Spacecraft taxonomies and ontologies (generalization hierarchies with attributes and relationships, based on terms meanings) are being developed for types of subsystems, functions, entities, hazards and failures. The ontologies are broad and general, covering hardware, software and human systems. Semantic search of Space Station texts was used to validate and extend the taxonomies. The taxonomies have also been used to extract system connectivity (interaction) models and functions from requirements text. Now the Reconciler semantic search tool and the taxonomies are being applied to improve search in the Space Shuttle PRACA database, to discover recurring patterns of failure. Usual methods of string search and keyword search fall short because the entries are terse and have numerous shortcuts (irregular abbreviations, nonstandard acronyms, cryptic codes) and modifier words cannot be used in sentence context to refine the search. The limited and fixed FMEA categories associated with the entries do not make the fine distinctions needed in the search. The approach assigns PRACA report titles to problem classes in the taxonomy. Each ontology class includes mapping words - near-synonyms naming different manifestations of that problem class. The mapping words for Problems, Entities and Functions are converted to a canonical form plus any of a small set of modifier words (e.g. non-uniformity NOT + UNIFORM.) The report titles are parsed as sentences if possible, or treated as a flat sequence of word tokens if parsing fails. When canonical forms in the title match mapping words, the PRACA entry is associated with the corresponding Problem, Entity or Function in the ontology. The user can search for types of failures associated with types of equipment, clustering by type of problem (e.g., all bearings found with problems of being uneven: rough, irregular, gritty ). The results could also be used for tagging PRACA report entries with rich metadata. This approach could also be applied to searching and tagging failure modes, failure effects and mitigations in FMEAs. In the pilot work, parsing 52K+ truncated titles (the test cases that were available), has resulted in identification of both a type of equipment and type of problem in about 75% of the cases. The results are displayed in a manner analogous to Google search results. The effort has also led to the enrichment of the taxonomy, adding some new categories and many new mapping words. Further work would make enhancements that have been identified for improving the clustering and further reducing the false alarm rate. (In searching for recurring problems, good clustering is more important than reducing false alarms). Searching complete PRACA reports should lead to immediate improvement.

Providing Real Research Opoportunities to Undergraduates

NASA Astrophysics Data System (ADS)

Ragozzine, Darin

2016-01-01

The current approach to undergraduate education focuses on teaching classes which provide the foundational knowledge for more applied experiences such as scientific research. Like most programs, Florida Institute of Technology (Florida Tech or FIT) strongly encourages undergraduate research, but is dominated by content-focused courses (e.g., "Physical Mechanics"). Research-like experiences are generally offered through "lab" classes, but these are almost always reproductions of past experiments: contrived, formulaic, and lacking the "heart" of real (i.e., potentially publishable) scientific research. Real research opportunities 1) provide students with realistic insight into the actual scientific process; 2) excite students far more than end-of-chapter problems; 3) provide context for the importance of learning math, physics, and astrophysics concepts; and 4) allow unique research progress for well-chosen problems. I have provided real research opportunities as an "Exoplanet Lab" component of my Introduction to Space Science (SPS1020) class at Florida Tech, generally taken by first-year majors in our Physics, Astronomy & Astrophysics, Planetary Science, and Astrobiology degree programs. These labs are a hybrid between citizen science (e.g., PlanetHunters) and simultaneously mentoring ~60 undergraduates in similar small research projects. These projects focus on problems that can be understood in the context of the course, but which benefit from "crowdsourcing". Examples include: dividing up the known planetary systems and developing a classification scheme and organizing them into populations (Fall 2013); searching through folded light curves to discover new exoplanets missed by previous pipelines (Fall 2014); and fitting n-body models to all exoplanets with known Transit Timing Variations to estimate planet masses (Fall 2015). The students love the fact that they are doing real potentially publishable research: not many undergraduates can claim to have discovered new exoplanets! Based on these experiences, I will present practical insights into successfully organizing real research opportunities. By employing some of these best practices, we can truly educate students and make scientific progress.

The role of neighborhood economic context on physical activity among children: Evidence from the Geographic Research on Wellbeing (GROW) study.

PubMed

Kim, Yeonwoo; Cubbin, Catherine

2017-08-01

Less than half of young children in the U.S. meet physical activity recommendations. While neighborhood economic context has been shown to be associated with physical activity, it is unknown whether this association varies according to family economic context. This study thus investigates whether neighborhood economic context, measured by poverty concentration and income inequality, are associated with physical activity among poor and non-poor children using data from the Geographic Research on Wellbeing study, California, 2012-2013 (N=2670). Poor children who resided in (a) poor and equal neighborhoods or (b) non-poor and equal neighborhoods were more likely to engage in sufficient physical activity than were children residing in non-poor and unequal neighborhoods. Poor children in (a) non-poor and equal neighborhoods, (b) poor and equal neighborhoods, or (c) poor and unequal neighborhoods were less likely to report insufficient physical activity than those in non-poor and unequal neighborhoods. Neighborhood economic context was not associated with physical activity among non-poor children. Findings suggest that neighborhood economic context presents a social barrier to physical activity among poor children. Increasing physical activity among poor children in non-poor and unequal neighborhoods should be a high policy priority. Perceived social cohesion, perceived neighborhood safety, and park and walkability indicators did not mediate the associations between neighborhood economic context and physical activity. Further research needs to explore the mechanisms by which neighborhood economic context affects physical activity among children. Copyright © 2017 Elsevier Inc. All rights reserved.

[Problem based learning from the perspective of tutors].

PubMed

Navarro Hernández, Nancy; Illesca P, Mónica; Cabezas G, Mirtha

2009-02-01

Problem based learning is a student centered learning technique that develops deductive, constructive and reasoning capacities among the students. Teachers must adapt to this paradigm of constructing rather than transmitting knowledge. To interpret the importance of tutors in problem based learning during a module of Health research and management given to medical, nursing, physical therapy, midwifery, technology and nutrition students. Eight teachers that participated in a module using problem based learning accepted to participate in an in depth interview. The qualitative analysis of the textual information recorded, was performed using the ATLAS software. We identified 662 meaning units, grouped in 29 descriptive categories, with eight emerging meta categories. The sequential and cross-generated qualitative analysis generated four domains: competence among students, competence of teachers, student-centered learning and evaluation process. Multiprofessional problem based learning contributes to the development of generic competences among future health professionals, such as multidisciplinary work, critical capacity and social skills. Teachers must shelter the students in the context of their problems and social situation.

Prediction of brittleness based on anisotropic rock physics model for kerogen-rich shale

NASA Astrophysics Data System (ADS)

Qian, Ke-Ran; He, Zhi-Liang; Chen, Ye-Quan; Liu, Xi-Wu; Li, Xiang-Yang

2017-12-01

The construction of a shale rock physics model and the selection of an appropriate brittleness index ( BI) are two significant steps that can influence the accuracy of brittleness prediction. On one hand, the existing models of kerogen-rich shale are controversial, so a reasonable rock physics model needs to be built. On the other hand, several types of equations already exist for predicting the BI whose feasibility needs to be carefully considered. This study constructed a kerogen-rich rock physics model by performing the selfconsistent approximation and the differential effective medium theory to model intercoupled clay and kerogen mixtures. The feasibility of our model was confirmed by comparison with classical models, showing better accuracy. Templates were constructed based on our model to link physical properties and the BI. Different equations for the BI had different sensitivities, making them suitable for different types of formations. Equations based on Young's Modulus were sensitive to variations in lithology, while those using Lame's Coefficients were sensitive to porosity and pore fluids. Physical information must be considered to improve brittleness prediction.

Characterization of NEOs from the Policy Perspective: Implications from Problem and Solution Definitions

NASA Astrophysics Data System (ADS)

Lindquist, E.

2015-12-01

The characterization of near-Earth-objects (NEOs) in regard to physical attributes and potential risk and impact factors presents a complex and complicates scientific and engineering challenge. The societal and policy risks and impacts are no less complex, yet are rarely considered in the same context as material properties or related factors. The objective of this contribution is to position the characterization of NEOs within the public policy process domain as a means to reflect on the science-policy nexus in regard to risks associated with NEOs. This will be accomplished through, first, a brief overview of the science-policy nexus, followed by a discussion of several policy process frameworks, such as agenda setting and the multiple streams model, focusing events, and punctuated equilibrium, and their application and appropriateness to the problem of NEOs. How, too, for example, does NEO hazard and risk compare with other low probability, high risk, hazards in regard to public policy? Finally, we will reflect on the implications of alternative NEO "solutions" and the characterization of the NEO "problem," and the political and public acceptance of policy alternatives as a way to link NEO science and policy in the context of the overall NH004 panel.

The psychology of thinking before the cognitive revolution: Otto Selz on problems, schemas, and creativity.

PubMed

ter Hark, Michel

2010-02-01

Otto Selz has been hailed as one of the most important precursors of the cognitive revolution, yet surprisingly few studies of his work exist. He is often mentioned in the context of the Würzburg School of the psychology of thinking and sometimes in the context of Gestalt psychology. In this paper, it is argued that Selz's emphasis on the role of problems and schemas in the direction of thought processes and creativity sets him apart from the program of the Würzburg School. On the other hand, by developing a theory of thinking that is exclusively at the intentional level, Selz also differs from psychologists that take physics as a model for psychology, such as the Gestalt psychology of Wolfgang Kihler. Special emphasis is given in this paper to Selz's use of the concept of problem or task and the concept of the schema. It is further argued that the concept of the schema is the result of Selz's adaptation of the theory of relations as developed by the philosopher Meinong. The paper begins with a sketch of Selz's life that ended so tragically.

A multidisciplinary approach of the problem of noise nuisance in urban environment

NASA Astrophysics Data System (ADS)

Rabah, Derbal Cobis; Hamza, Zeghlache

2002-05-01

More often the problem of noise and sonic pollution, particularly in urban sites, is studied by different disciplines such as physics, the acoustics, the psychoacoustics, the medicine and others. It is independently of each other that these sciences are often approaching this subject. Some studies are carried out in laboratories taking noise as samples cut off their realistic context. Urban noise is studied as well by making an abstraction of the different contextual parameters by idealizing a rather complex sonic environment. The noise, according to this present approach, is suposed to react with surounding space, and it takes the form and the quality of the place by defining and requalifying it. It is found that the contextual aspects such as social, cultural or even symbolic dimensions modulate the listening conditions and the perception quality of the noise and even the living and the daily practice of the urban space. The multiparameter dimension study of the noise in an urban context is necessary to better work out the problem and to try to come up with some practical and efficient solutions. The little amount of studies based on such multidisciplinary approach, confort well our effort to go ahead with this methodological approach.

A Wicked Problem: Early Childhood Safety in the Dynamic, Interactive Environment of Home

PubMed Central

Simpson, Jean; Fougere, Geoff; McGee, Rob

2013-01-01

Young children being injured at home is a perennial problem. When parents of young children and family workers discussed what influenced parents’ perceptions and responses to child injury risk at home, both “upstream” and “downstream” causal factors were identified. Among the former, complex and interactive facets of society and contemporary living emerged as potentially critical features. The “wicked problems” model arose from the need to find resolutions for complex problems in multidimensional environments and it proved a useful analogy for child injury. Designing dynamic strategies to provide resolutions to childhood injury, may address our over-dependence on ‘tame solutions’ that only deal with physical cause-and-effect relationships and which cannot address the complex interactive contexts in which young children are often injured. PMID:23615453

Female sex workers and the social context of workplace violence in Tijuana, Mexico.

PubMed

Katsulis, Yasmina; Lopez, Vera; Durfee, Alesha; Robillard, Alyssa

2010-09-01

Gender-based violence in the workplace impacts the physical and emotional wellbeing of sex workers and may lead to other health problems, such as PTSD and depression, drug abuse, and a greater likelihood of sexually transmitted infections. This study examines the social context of workplace violence and risk avoidance in the context of legal regulations meant to reduce harms associated with the industry. Ethnographic research, including 18 months of extended field observations and interviews with 190 female sex workers, is used to illustrate how sex workers in Tijuana, Mexico, experience and manage workplace violence. Multiple subthemes emerge from this analysis, including deciding where to work, working with a third party, avoiding theft, and dealing with police. These findings support the idea that the risk of violence is part of a larger "hierarchy of risk" that can result in a "tradeoff" of harms.

Identification of mutated driver pathways in cancer using a multi-objective optimization model.

PubMed

Zheng, Chun-Hou; Yang, Wu; Chong, Yan-Wen; Xia, Jun-Feng

2016-05-01

New-generation high-throughput technologies, including next-generation sequencing technology, have been extensively applied to solve biological problems. As a result, large cancer genomics projects such as the Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium are producing large amount of rich and diverse data in multiple cancer types. The identification of mutated driver genes and driver pathways from these data is a significant challenge. Genome aberrations in cancer cells can be divided into two types: random 'passenger mutation' and functional 'driver mutation'. In this paper, we introduced a Multi-objective Optimization model based on a Genetic Algorithm (MOGA) to solve the maximum weight submatrix problem, which can be employed to identify driver genes and driver pathways promoting cancer proliferation. The maximum weight submatrix problem defined to find mutated driver pathways is based on two specific properties, i.e., high coverage and high exclusivity. The multi-objective optimization model can adjust the trade-off between high coverage and high exclusivity. We proposed an integrative model by combining gene expression data and mutation data to improve the performance of the MOGA algorithm in a biological context. Copyright © 2016 Elsevier Ltd. All rights reserved.

Phenomenology of pure-gauge hidden valleys at hadron colliders

NASA Astrophysics Data System (ADS)

Juknevich, Jose E.

Expectations for new physics at the LHC have been greatly influenced by the Hierarchy problem of electroweak symmetry breaking. However, there are reasons to believe that the LHC may still discover new physics, but not directly related to the resolution of the Hierarchy problem. To ensure that such a physics does not go undiscovered requires precise understanding of how new phenomena will reveal themselves in the current and future generation of particle-physics experiments. Given this fact it seems sensible to explore other approaches to this problem; we study three alternatives here. In this thesis I argue for the plausibility that the standard model is coupled, through new massive charged or colored particles, to a hidden sector whose low energy dynamics is controlled by a pure Yang-Mills theory, with no light matter. Such a sector would have numerous metastable "hidden glueballs" built from the hidden gluons. These states would decay to particles of the standard model. I consider the phenomenology of this scenario, and find formulas for the lifetimes and branching ratios of the most important of these states. The dominant decays are to two standard model gauge bosons or to fermion-antifermion pairs, or by radiative decays with photon or Higgs emission, leading to jet- and photon-rich signals, and some occasional leptons. The presence of effective operators of different mass dimensions, often competing with each other, together with a great diversity of states, leads to a great variability in the lifetimes and decay modes of the hidden glueballs. I find that most of the operators considered in this work are not heavily constrained by precision electroweak physics, therefore leaving plenty of room in the parameter space to be explored by the future experiments at the LHC. Finally, I discuss several issues on the phenomenology of the new massive particles as well as an outlook for experimental searches.

The turbulent formation of stars

NASA Astrophysics Data System (ADS)

Federrath, Christoph

2018-06-01

How stars are born from clouds of gas is a rich physics problem whose solution will inform our understanding of not just stars but also planets, galaxies, and the universe itself. Star formation is stupendously inefficient. Take the Milky Way. Our galaxy contains about a billion solar masses of fresh gas available to form stars-and yet it produces only one solar mass of new stars a year. Accounting for that inefficiency is one of the biggest challenges of modern astrophysics. Why should we care about star formation? Because the process powers the evolution of galaxies and sets the initial conditions for planet formation and thus, ultimately, for life.

Physical and emotional health problems experienced by youth engaged in physical fighting and weapon carrying.

PubMed

Walsh, Sophie D; Molcho, Michal; Craig, Wendy; Harel-Fisch, Yossi; Huynh, Quynh; Kukaswadia, Atif; Aasvee, Katrin; Várnai, Dora; Ottova, Veronika; Ravens-Sieberer, Ulrike; Pickett, William

2013-01-01

Then aims of the current study were 1) to provide cross-national estimates of the prevalence of physical fighting and weapon carrying among adolescents aged 11-15 years; (2) To examine the possible effects of physical fighting and weapon carrying on the occurrence of physical (medically treated injuries) and emotional health outcomes (multiple health complaints) among adolescents within the theoretical framework of Problem Behaviour Theory. 20,125 adolescents aged 11-15 in five countries (Belgium, Israel, USA, Canada, FYR Macedonia) were surveyed via the 2006 Health Behaviour in School Aged Children survey. Prevalence was calculated for physical fighting and weapon carrying along with physical and emotional measures that potentially result from violence. Regression analyses were used to quantify associations between violence/weapon carrying and the potential health consequences within each country. Large variations in fighting and weapon carrying were observed across countries. Boys reported more frequent episodes of fighting/weapon carrying and medically attended injuries in every country, while girls reported more emotional symptoms. Although there were some notable variations in findings between different participating countries, increased weapon carrying and physical fighting were both independently and consistently associated with more frequent reports of the potential health outcomes. Adolescents engaging in fighting and weapon carrying are also at risk for physical and emotional health outcomes. Involvement in fighting and weapon carrying can be seen as part of a constellation of risk behaviours with obvious health implications. Our findings also highlight the importance of the cultural context when examining the nature of violent behaviour for adolescents.

Physical and Emotional Health Problems Experienced by Youth Engaged in Physical Fighting and Weapon Carrying

PubMed Central

Walsh, Sophie D.; Molcho, Michal; Craig, Wendy; Harel-Fisch, Yossi; Huynh, Quynh; Kukaswadia, Atif; Aasvee, Katrin; Várnai, Dora; Ottova, Veronika; Ravens-Sieberer, Ulrike; Pickett, William

2013-01-01

Then aims of the current study were 1) to provide cross-national estimates of the prevalence of physical fighting and weapon carrying among adolescents aged 11–15 years; (2) To examine the possible effects of physical fighting and weapon carrying on the occurrence of physical (medically treated injuries) and emotional health outcomes (multiple health complaints) among adolescents within the theoretical framework of Problem Behaviour Theory. 20,125 adolescents aged 11–15 in five countries (Belgium, Israel, USA, Canada, FYR Macedonia) were surveyed via the 2006 Health Behaviour in School Aged Children survey. Prevalence was calculated for physical fighting and weapon carrying along with physical and emotional measures that potentially result from violence. Regression analyses were used to quantify associations between violence/weapon carrying and the potential health consequences within each country. Large variations in fighting and weapon carrying were observed across countries. Boys reported more frequent episodes of fighting/weapon carrying and medically attended injuries in every country, while girls reported more emotional symptoms. Although there were some notable variations in findings between different participating countries, increased weapon carrying and physical fighting were both independently and consistently associated with more frequent reports of the potential health outcomes. Adolescents engaging in fighting and weapon carrying are also at risk for physical and emotional health outcomes. Involvement in fighting and weapon carrying can be seen as part of a constellation of risk behaviours with obvious health implications. Our findings also highlight the importance of the cultural context when examining the nature of violent behaviour for adolescents. PMID:23437126

Language of Physics, Language of Math: Disciplinary Culture and Dynamic Epistemology

NASA Astrophysics Data System (ADS)

Redish, Edward F.; Kuo, Eric

2015-07-01

Mathematics is a critical part of much scientific research. Physics in particular weaves math extensively into its instruction beginning in high school. Despite much research on the learning of both physics and math, the problem of how to effectively include math in physics in a way that reaches most students remains unsolved. In this paper, we suggest that a fundamental issue has received insufficient exploration: the fact that in science, we don't just use math, we make meaning with it in a different way than mathematicians do. In this reflective essay, we explore math as a language and consider the language of math in physics through the lens of cognitive linguistics. We begin by offering a number of examples that show how the use of math in physics differs from the use of math as typically found in math classes. We then explore basic concepts in cognitive semantics to show how humans make meaning with language in general. The critical elements are the roles of embodied cognition and interpretation in context. Then, we show how a theoretical framework commonly used in physics education research, resources, is coherent with and extends the ideas of cognitive semantics by connecting embodiment to phenomenological primitives and contextual interpretation to the dynamics of meaning-making with conceptual resources, epistemological resources, and affect. We present these ideas with illustrative case studies of students working on physics problems with math and demonstrate the dynamical nature of student reasoning with math in physics. We conclude with some thoughts about the implications for instruction.

Amazing Physics: Learning about Work, Energy and Projectile Motion in a Historical Context

ERIC Educational Resources Information Center

Tural, Guner

2013-01-01

Teaching physics through a historical context provides effective learning and increases students' motivation for and interest in physics. For example, trebuchets and mangonels may be interesting historical contexts for learning about energy, work, and projectile motion. In this study, the implementation of physics lessons related to these subjects…

The Chemical Adventures of Sherlock Holmes: The Baker Street Burning

NASA Astrophysics Data System (ADS)

Waddell, Thomas G.; Rybolt, Thomas R.

1998-04-01

This story describes a chemical mystery with an emphasis on forensic chemistry, physical properties, and qualitative organic analysis. This is the ninth article in a series presenting a scientific problem in mystery form in the context of the popular and beloved characters Sherlock Holmes and Dr. Watson. There is a break in the story where the reader (students and teachers) can ponder and solve the mystery. Sherlock Holmes provides his solution in the paragraphs following this break.

The Chemical Adventures of Sherlock Holmes: The Case of Three

NASA Astrophysics Data System (ADS)

Rybolt, Thomas R.; Waddell, Thomas G.

2002-04-01

This story is a chemical mystery with an emphasis on simple physical properties and chemical characterization of metals. It is the 13th in a series presenting scientific problems in mystery format in the context of the popular and beloved characters Sherlock Holmes and Dr. Watson. There is a break in the story where the reader (students and teachers) can ponder and solve the mystery. Sherlock Holmes provides his solution in the paragraphs following this break.

A collaborative learning approach for service-oriented introductory physics

NASA Astrophysics Data System (ADS)

Smith, Michael R.

1997-03-01

I have taught algebra-based introductory physics for six years to liberal arts students. It was primarily a service course for students majoring in Athletic Training, Physical Therapy, Geology, Biology, and Pre-Med. The typical student was characterized by having a minimal math and problem-solving proficiency. There also was a pattern of students being predisposed to memorizing facts and formulas, and attempting to solve problems by finding the correct formula and "plugging in" numbers to get an answer. The students seemed to have a minimal ability in deductive reasoning and problem solving, starting from basic principles. It is no wonder that they entered the introductory physics service course with extreme trepidation, based upon a strongly perceived physics phobia. A standard lecture format was used for the class size of approximately 25-30 students; and an attempt was always made to engage the students through the Socratic approach, by asking leading questions during the course of the lecture. The students were relatively unprepared and couldn't participate in the class, and often responded antagonistically. They indicated they didn't want to be asked to think about an issue, but would rather just be told the facts so they could take specific notes for subsequent memorization. It was clear from the results of the open book exams given during the semester that the majority of students could not approach problem solving using deductive reasoning based on basic principles, but relied on attempting to force-fit the problem into a worked example in the text (often out of context, with illogical results). The absentee rate in the classroom was usually around 30-40%. The academic administration of my liberal arts university has the policy of formal course evaluations by the students at the end of each semester. The evaluation questionnaire appears to be primarily a measurement of the stress level of the student during the course, and the evaluation score I received for the service physics course was typically on the order of 3 out of a possible 5; a score considered unsatisfactory by the administration.

Feminist ethics and the metaphor of AIDS.

PubMed

Sherwin, S

2001-08-01

This paper looks at a range of metaphors used within HIV/AIDS discussions and research in support of the claim that bioethicists should pay serious attention to metaphors. Metaphors shape the ways we think about problems and the types of solutions we investigate. HIV/AIDS is an especially rich field for the investigation of metaphor, since the struggles for dominance among different metaphorical options has been very evident. In the field of medical research as well as in the area of public policy, different metaphors support different strategies and, therefore, the choice of metaphor has ethical significance. I argue that feminists should engage in these debates since they have an interest in the metaphors selected. They can also learn to be more self-conscious in choosing politically liberating metaphors in other bioethics contexts.

Electronic Medical Records (EMRs), Epidemiology, and Epistemology: Reflections on EMRs and Future Pediatric Clinical Research

PubMed Central

Wasserman, Richard C.

2011-01-01

Electronic medical records (EMRs) are increasingly common in pediatric patient care. EMR data represent a relatively novel and rich resource for clinical research. The fact, however, that pediatric EMR data are collected for the purposes of clinical documentation and billing rather than research creates obstacles to their use in scientific investigation. Particular issues include accuracy, completeness, comparability between settings, ease of extraction, and context of recording. Although these problems can be addressed through standard strategies for dealing with partially accurate and incomplete data, a longer term solution will involve work with pediatric clinicians to improve data quality. As research becomes one of the explicit purposes for which pediatricians collect EMR data, the pediatric clinician will play a central role in future pediatric clinical research. PMID:21622040

Expanding color design methods for architecture and allied disciplines

NASA Astrophysics Data System (ADS)

Linton, Harold E.

2002-06-01

The color design processes of visual artists, architects, designers, and theoreticians included in this presentation reflect the practical role of color in architecture. What the color design professional brings to the architectural design team is an expertise and rich sensibility made up of a broad awareness and a finely tuned visual perception. This includes a knowledge of design and its history, expertise with industrial color materials and their methods of application, an awareness of design context and cultural identity, a background in physiology and psychology as it relates to human welfare, and an ability to problem-solve and respond creatively to design concepts with innovative ideas. The broadening of the definition of the colorists's role in architectural design provides architects, artists and designers with significant opportunities for continued professional and educational development.

Setting the stage for chronic health problems: cumulative childhood adversity among homeless adults with mental illness in Vancouver, British Columbia.

PubMed

Patterson, Michelle L; Moniruzzaman, Akm; Somers, Julian M

2014-04-12

It is well documented that childhood abuse, neglect and household dysfunction are disproportionately present in the backgrounds of homeless adults, and that these experiences adversely impact child development and a wide range of adult outcomes. However, few studies have examined the cumulative impact of adverse childhood experiences on homeless adults with mental illness. This study examines adverse events in childhood as predictors of duration of homelessness, psychiatric and substance use disorders, and physical health in a sample of homeless adults with mental illness. This study was conducted using baseline data from a randomized controlled trial in Vancouver, British Columbia for participants who completed the Adverse Childhood Experiences (ACE) scale at 18 months follow-up (n=364). Primary outcomes included current mental disorders; substance use including type, frequency and severity; physical health; duration of homelessness; and vocational functioning. In multivariable regression models, ACE total score independently predicted a range of mental health, physical health, and substance use problems, and marginally predicted duration of homelessness. Adverse childhood experiences are overrepresented among homeless adults with complex comorbidities and chronic homelessness. Our findings are consistent with a growing body of literature indicating that childhood traumas are potent risk factors for a number of adult health and psychiatric problems, particularly substance use problems. Results are discussed in the context of cumulative adversity and self-trauma theory. This trial has been registered with the International Standard Randomized Control Trial Number Register and assigned ISRCTN42520374.

Network Analysis of Students' Use of Representations in Problem Solving

NASA Astrophysics Data System (ADS)

McPadden, Daryl; Brewe, Eric

2016-03-01

We present the preliminary results of a study on student use of representations in problem solving within the Modeling Instruction - Electricity and Magnetism (MI-E&M) course. Representational competence is a critical skill needed for students to develop a sophisticated understanding of college science topics and to succeed in their science courses. In this study, 70 students from the MI-E&M, calculus-based course were given a survey of 25 physics problem statements both pre- and post- instruction, covering both Newtonian Mechanics and Electricity and Magnetism (E&M). For each problem statement, students were asked which representations they would use in that given situation. We analyze the survey results through network analysis, identifying which representations are linked together in which contexts. We also compare the representation networks for those students who had already taken the first-semester Modeling Instruction Mechanics course and those students who had taken a non-Modeling Mechanics course.

Enhancing Students' Problem-Solving Skills through Context-Based Learning

ERIC Educational Resources Information Center

Yu, Kuang-Chao; Fan, Szu-Chun; Lin, Kuen-Yi

2015-01-01

Problem solving is often challenging for students because they do not understand the problem-solving process (PSP). This study presents a three-stage, context-based, problem-solving, learning activity that involves watching detective films, constructing a context-simulation activity, and introducing a project design to enable students to construct…

Tuning Out the World with Noise-Canceling Headphones

ERIC Educational Resources Information Center

McCulloch, Allison W.; Whitehead, Ashley; Lovett, Jennifer N.; Whitley, Blake

2017-01-01

Context is what makes mathematical modeling tasks different from more traditional textbook word problems. Math problems are sometimes stripped of context as they are worked on. For modeling problems, however, context is important for making sense of the mathematics. The task should be brought back to its real-world context as often as possible. In…

VET Workers' Problem-Solving Skills in Technology-Rich Environments: European Approach

ERIC Educational Resources Information Center

Hämäläinen, Raija; Cincinnato, Sebastiano; Malin, Antero; De Wever, Bram

2014-01-01

The European workplace is challenging VET adults' problem-solving skills in technology-rich environments (TREs). So far, no international large-scale assessment data has been available for VET. The PIAAC data comprise the most comprehensive source of information on adults' skills to date. The present study (N = 50 369) focuses on gaining insight…

Beyond deficits: intimate partner violence, maternal parenting, and child behavior over time.

PubMed

Greeson, Megan R; Kennedy, Angie C; Bybee, Deborah I; Beeble, Marisa; Adams, Adrienne E; Sullivan, Cris

2014-09-01

Exposure to intimate partner violence (IPV) has negative consequences for children's well-being and behavior. Much of the research on parenting in the context of IPV has focused on whether and how IPV victimization may negatively shape maternal parenting, and how parenting may in turn negatively influence child behavior, resulting in a deficit model of mothering in the context of IPV. However, extant research has yet to untangle the interrelationships among the constructs and test whether the negative effects of IPV on child behavior are indeed attributable to IPV affecting mothers' parenting. The current study employed path analysis to examine the relationships among IPV, mothers' parenting practices, and their children's externalizing behaviors over three waves of data collection among a sample of 160 women with physically abusive partners. Findings indicate that women who reported higher levels of IPV also reported higher levels of behavior problems in their children at the next time point. When parenting practices were examined individually as mediators of the relationship between IPV and child behavior over time, one type of parenting was significant, such that higher IPV led to higher authoritative parenting and lower child behavior problems [corrected]. On the other hand, there was no evidence that higher levels of IPV contributed to more child behavior problems due to maternal parenting. Instead, IPV had a significant cumulative indirect effect on child behavior via the stability of both IPV and behavior over time. Implications for promoting women's and children's well-being in the context of IPV are discussed.

Nutrition and Physical Performance in Military Environments

DTIC Science & Technology

1987-12-01

6 4.0 Adaptations to fat -rich diets ............................................................................... 7 5.0 M icronutrients and...dense, fat -rich, i.e carbohydrate-poor, diet may be possible although the time course and extent of adaptation mu3t be clarified before such a diet can be...anorexia which can result in insufficient energy and/or carbohydrate intake to maintain optimal physical peeformance. Cold environments are usually

Terrain and vegetation structural influences on local avian species richness in two mixed-conifer forests

Treesearch

Jody C. Vogeler; Andrew T. Hudak; Lee A. Vierling; Jeffrey Evans; Patricia Green; Kerri T. Vierling

2014-01-01

Using remotely-sensed metrics to identify regions containing high animal diversity and/or specific animal species or guilds can help prioritize forest management and conservation objectives across actively managed landscapes. We predicted avian species richness in two mixed conifer forests, Moscow Mountain and Slate Creek, containing different management contexts and...

Suppression of Literal Meanings in L2 Idiom Processing: Does Context Help?

ERIC Educational Resources Information Center

Cieslicka, Anna B.

2011-01-01

Most current idiom processing models acknowledge, after Gernsbacher and Robertson (1999) that deriving an idiomatic meaning entails suppression of contextually inappropriate, literal meanings of idiom constituent words. While embedding idioms in the rich disambiguating context can promote earlier suppression of incompatible literal meanings,…

Rich Schools, Poor Schools. Hidden Resource Inequalities between Primary Schools

ERIC Educational Resources Information Center

Poesen-Vandeputte, Mayke; Nicaise, Ides

2015-01-01

Background: There has been relatively little analysis of school context including a large number of elements from the broader social, political and economic influences. However, primary schools in Flanders (Belgium) are supposed to consider their school context when implementing the Flemish policy on equal opportunities in education. Purpose: In…

Understanding the role of contrasting urban contexts in healthy aging: an international cohort study using wearable sensor devices (the CURHA study protocol).

PubMed

Kestens, Yan; Chaix, Basile; Gerber, Philippe; Desprès, Michel; Gauvin, Lise; Klein, Olivier; Klein, Sylvain; Köppen, Bernhard; Lord, Sébastien; Naud, Alexandre; Payette, Hélène; Richard, Lucie; Rondier, Pierre; Shareck, Martine; Sueur, Cédric; Thierry, Benoit; Vallée, Julie; Wasfi, Rania

2016-05-05

Given the challenges of aging populations, calls have been issued for more sustainable urban re-development and implementation of local solutions to address global environmental and healthy aging issues. However, few studies have considered older adults' daily mobility to better understand how local built and social environments may contribute to healthy aging. Meanwhile, wearable sensors and interactive map-based applications offer novel means for gathering information on people's mobility, levels of physical activity, or social network structure. Combining such data with classical questionnaires on well-being, physical activity, perceived environments and qualitative assessment of experience of places opens new opportunities to assess the complex interplay between individuals and environments. In line with current gaps and novel analytical capabilities, this research proposes an international research agenda to collect and analyse detailed data on daily mobility, social networks and health outcomes among older adults using interactive web-based questionnaires and wearable sensors. Our study resorts to a battery of innovative data collection methods including use of a novel multisensor device for collection of location and physical activity, interactive map-based questionnaires on regular destinations and social networks, and qualitative assessment of experience of places. This rich data will allow advanced quantitative and qualitative analyses in the aim to disentangle the complex people-environment interactions linking urban local contexts to healthy aging, with a focus on active living, social networks and participation, and well-being. This project will generate evidence about what characteristics of urban environments relate to active mobility, social participation, and well-being, three important dimensions of healthy aging. It also sets the basis for an international research agenda on built environment and healthy aging based on a shared and comprehensive data collection protocol.

From Crew Communication to Coordination: A Fundamental Means to an End

NASA Technical Reports Server (NTRS)

Kanki, Barbara G.; Connors, Mary M. (Technical Monitor)

1998-01-01

This viewgraph presentation describes the purposes and contexts of communication, factors which affect the interpretation of communication, and the advantages of effective, systematic communication to and from crews. Communication accomplishes information transfer, team/task management, shared problem solving and decision making, and establishment of the interpersonal climate. These accomplishments support outcomes: Technical task performance; CRM (crew resource management); Procedures and ATC (air traffic control); and Work/team atmosphere. The presentation lists various types of management inefficiency which can result from a lack of each of the four accomplishments. Communication skills are used within the following contexts: physical; social and organizational; task and operational; and speech and linguistic. Crew communication can be evaluated through investigation (case study), research (experimentation), and training.

Cognitive science as an interface between rational and mechanistic explanation.

PubMed

Chater, Nick

2014-04-01

Cognitive science views thought as computation; and computation, by its very nature, can be understood in both rational and mechanistic terms. In rational terms, a computation solves some information processing problem (e.g., mapping sensory information into a description of the external world; parsing a sentence; selecting among a set of possible actions). In mechanistic terms, a computation corresponds to causal chain of events in a physical device (in engineering context, a silicon chip; in biological context, the nervous system). The discipline is thus at the interface between two very different styles of explanation--as the papers in the current special issue well illustrate, it explores the interplay of rational and mechanistic forces. Copyright © 2014 Cognitive Science Society, Inc.

[El niño phenomenon and natural disasters: public health interventions for disaster preparedness and response].

PubMed

Hijar, Gisely; Bonilla, Catherine; Munayco, Cesar V; Gutierrez, Ericson L; Ramos, Willy

2016-06-01

This article reviews public health interventions for preparedness and response to natural disasters within the context of El Niño phenomenon using systematic reviews and a review of revisions with emphasis on vector-borne diseases, water-borne diseases, malnutrition, heat stress, drought, flood-associated diseases, mental health problems, vulnerability of the physical health-system infrastructure, as well as long-term policies aimed at protecting the populations of these cases. Environmental interventions were identified, including vector control, chemoprophylaxis, immunization, and intradomiciliary water treatment. While these finds are based primarily on systematic reviews, it is necessary to evaluate the benefit of these interventions within the population, according to the context of each region.

Does cultural context make a difference to women's experiences of maternity care? A qualitative study comparing the perspectives of breast-feeding women of Bangladeshi origin and health practitioners.

PubMed

McFadden, Alison; Renfrew, Mary J; Atkin, Karl

2013-12-01

Maternity services struggle to provide culturally appropriate care that meets the needs of women from diverse populations. Problems include simplistic understandings of ethnicity and the role of culture in women's lives, and stereotypes held by health practitioners. To explore the extent to which cultural context makes a difference to experiences of breast-feeding support for women of Bangladeshi origin and to consider the implications for the provision of culturally appropriate care. The study comprised individual interviews with 23 women of Bangladeshi origin and four health service managers, and focus group discussions with 28 health practitioners between February and December 2008. Participants were recruited from four localities in northern England. Women's rich descriptions of various facets of their identities were in contrast to practitioners' representations of women of Bangladeshi origin as homogenous. Practitioners did not recognize when the needs of women of Bangladeshi origin were similar to those of the majority white population, or where cultural context made a difference to their experiences of breast-feeding and breast-feeding support. Some practitioners used cultural stereotypes which, combined with organizational constraints, resulted in services not meeting many of the women's needs. Implications for education, policy and practice include the need for training of health practitioners to work with diverse populations, implementing evidence-based practice and providing an organizational context which supports practitioners to respond to diversity without using cultural stereotypes. © 2012 John Wiley & Sons Ltd.

Context-dependent interactions and the regulation of species richness in freshwater fish.

PubMed

MacDougall, Andrew S; Harvey, Eric; McCune, Jenny L; Nilsson, Karin A; Bennett, Joseph; Firn, Jennifer; Bartley, Timothy; Grace, James B; Kelly, Jocelyn; Tunney, Tyler D; McMeans, Bailey; Matsuzaki, Shin-Ichiro S; Kadoya, Taku; Esch, Ellen; Cazelles, Kevin; Lester, Nigel; McCann, Kevin S

2018-03-06

Species richness is regulated by a complex network of scale-dependent processes. This complexity can obscure the influence of limiting species interactions, making it difficult to determine if abiotic or biotic drivers are more predominant regulators of richness. Using integrative modeling of freshwater fish richness from 721 lakes along an 11 o latitudinal gradient, we find negative interactions to be a relatively minor independent predictor of species richness in lakes despite the widespread presence of predators. Instead, interaction effects, when detectable among major functional groups and 231 species pairs, were strong, often positive, but contextually dependent on environment. These results are consistent with the idea that negative interactions internally structure lake communities but do not consistently 'scale-up' to regulate richness independently of the environment. The importance of environment for interaction outcomes and its role in the regulation of species richness highlights the potential sensitivity of fish communities to the environmental changes affecting lakes globally.

Context-dependent interactions and the regulation of species richness in freshwater fish

USGS Publications Warehouse

MacDougall, Andrew S.; Harvey, Eric; McCune, Jenny L.; Nilsson, Karin A.; Bennett, Joseph; Firn, Jennifer; Bartley, Timothy; Grace, James B.; Kelly, Jocelyn; Tunney, Tyler D.; McMeans, Bailey; Matsuzaki, Shin-Ichiro S.; Kadoya, Taku; Esch, Ellen; Cazelles, Kevin; Lester, Nigel; McCann, Kevin S.

2018-01-01

Species richness is regulated by a complex network of scale-dependent processes. This complexity can obscure the influence of limiting species interactions, making it difficult to determine if abiotic or biotic drivers are more predominant regulators of richness. Using integrative modeling of freshwater fish richness from 721 lakes along an 11olatitudinal gradient, we find negative interactions to be a relatively minor independent predictor of species richness in lakes despite the widespread presence of predators. Instead, interaction effects, when detectable among major functional groups and 231 species pairs, were strong, often positive, but contextually dependent on environment. These results are consistent with the idea that negative interactions internally structure lake communities but do not consistently ‘scale-up’ to regulate richness independently of the environment. The importance of environment for interaction outcomes and its role in the regulation of species richness highlights the potential sensitivity of fish communities to the environmental changes affecting lakes globally.

Evolution of a designless nanoparticle network into reconfigurable Boolean logic

NASA Astrophysics Data System (ADS)

Bose, S. K.; Lawrence, C. P.; Liu, Z.; Makarenko, K. S.; van Damme, R. M. J.; Broersma, H. J.; van der Wiel, W. G.

2015-12-01

Natural computers exploit the emergent properties and massive parallelism of interconnected networks of locally active components. Evolution has resulted in systems that compute quickly and that use energy efficiently, utilizing whatever physical properties are exploitable. Man-made computers, on the other hand, are based on circuits of functional units that follow given design rules. Hence, potentially exploitable physical processes, such as capacitive crosstalk, to solve a problem are left out. Until now, designless nanoscale networks of inanimate matter that exhibit robust computational functionality had not been realized. Here we artificially evolve the electrical properties of a disordered nanomaterials system (by optimizing the values of control voltages using a genetic algorithm) to perform computational tasks reconfigurably. We exploit the rich behaviour that emerges from interconnected metal nanoparticles, which act as strongly nonlinear single-electron transistors, and find that this nanoscale architecture can be configured in situ into any Boolean logic gate. This universal, reconfigurable gate would require about ten transistors in a conventional circuit. Our system meets the criteria for the physical realization of (cellular) neural networks: universality (arbitrary Boolean functions), compactness, robustness and evolvability, which implies scalability to perform more advanced tasks. Our evolutionary approach works around device-to-device variations and the accompanying uncertainties in performance. Moreover, it bears a great potential for more energy-efficient computation, and for solving problems that are very hard to tackle in conventional architectures.

Mental reinstatement of encoding context improves episodic remembering.

PubMed

Bramão, Inês; Karlsson, Anna; Johansson, Mikael

2017-09-01

This study investigates context-dependent memory retrieval. Previous work has shown that physically re-experiencing the encoding context at retrieval improves memory accessibility. The current study examined if mental reconstruction of the original encoding context would yield parallel memory benefits. Participants performed a cued-recall memory task, preceded either by a mental or by a physical context reinstatement task, and we manipulated whether the context reinstated at retrieval overlapped with the context of the target episode. Both behavioral and electrophysiological measures of brain activity showed strong encoding-retrieval (E-R) overlap effects, with facilitated episodic retrieval when the encoding and retrieval contexts overlapped. The electrophysiological E-R overlap effect was more sustained and involved more posterior regions when context was mentally compared with physically reinstated. Additionally, a time-frequency analysis revealed that context reinstatement alone engenders recollection of the target episode. However, while recollection of the target memory is readily prompted by a physical reinstatement, target recollection during mental reinstatement is delayed and depends on the gradual reconstruction of the context. Taken together, our results show facilitated episodic remembering also when mentally reinstating the encoding context; and that such benefits are supported by both shared and partially non-overlapping neural mechanisms when the encoding context is mentally reconstructed as compared with physically presented at the time of retrieval. Copyright © 2017 Elsevier Ltd. All rights reserved.

Colour and Optical Properties of Materials: An Exploration of the Relationship Between Light, the Optical Properties of Materials and Colour

NASA Astrophysics Data System (ADS)

Tilley, Richard J. D.

2003-05-01

Colour is an important and integral part of everyday life, and an understanding and knowledge of the scientific principles behind colour, with its many applications and uses, is becoming increasingly important to a wide range of academic disciplines, from physical, medical and biological sciences through to the arts. Colour and the Optical Properties of Materials carefully introduces the science behind the subject, along with many modern and cutting-edge applications, chose to appeal to today's students. For science students, it provides a broad introduction to the subject and the many applications of colour. To more applied students, such as engineering and arts students, it provides the essential scientific background to colour and the many applications. Features: * Introduces the science behind the subject whilst closely connecting it to modern applications, such as colour displays, optical amplifiers and colour centre lasers * Richly illustrated with full-colour plates * Includes many worked examples, along with problems and exercises at the end of each chapter and selected answers at the back of the book * A Web site, including additional problems and full solutions to all the problems, which may be accessed at: www.cardiff.ac.uk/uwcc/engin/staff/rdjt/colour Written for students taking an introductory course in colour in a wide range of disciplines such as physics, chemistry, engineering, materials science, computer science, design, photography, architecture and textiles.

A Two-Stage Composition Method for Danger-Aware Services Based on Context Similarity

NASA Astrophysics Data System (ADS)

Wang, Junbo; Cheng, Zixue; Jing, Lei; Ota, Kaoru; Kansen, Mizuo

Context-aware systems detect user's physical and social contexts based on sensor networks, and provide services that adapt to the user accordingly. Representing, detecting, and managing the contexts are important issues in context-aware systems. Composition of contexts is a useful method for these works, since it can detect a context by automatically composing small pieces of information to discover service. Danger-aware services are a kind of context-aware services which need description of relations between a user and his/her surrounding objects and between users. However when applying the existing composition methods to danger-aware services, they show the following shortcomings that (1) they have not provided an explicit method for representing composition of multi-user' contexts, (2) there is no flexible reasoning mechanism based on similarity of contexts, so that they can just provide services exactly following the predefined context reasoning rules. Therefore, in this paper, we propose a two-stage composition method based on context similarity to solve the above problems. The first stage is composition of the useful information to represent the context for a single user. The second stage is composition of multi-users' contexts to provide services by considering the relation of users. Finally the danger degree of the detected context is computed by using context similarity between the detected context and the predefined context. Context is dynamically represented based on two-stage composition rules and a Situation theory based Ontology, which combines the advantages of Ontology and Situation theory. We implement the system in an indoor ubiquitous environment, and evaluate the system through two experiments with the support of subjects. The experiment results show the method is effective, and the accuracy of danger detection is acceptable to a danger-aware system.

Impact of Platelet-Rich Plasma on Viability and Proliferation in Wound Healing Processes after External Radiation

PubMed Central

Reinders, Yvonne; Felthaus, Oliver; Brockhoff, Gero; Pohl, Fabian; Prantl, Lukas; Haubner, Frank

2017-01-01

Platelet-rich plasma is a current subject of studies on chronic wound healing therapy due to possible pro-angiogenic effects. Microvascular compromise represents the major component in radiogenic wound healing complications. The effects of platelet-rich plasma on irradiated cells of the cutaneous wound healing process are poorly understood so far. In this study, the interaction of endothelial cells and adipose-derived stem cells in conjunction with treatment with platelet-rich plasma is investigated in the context of radiation effects. Therefore, the expression of surface-marker CD90 and CD31 was determined. Moreover, cell proliferation and viability after external radiation was analyzed with and without treatment by platelet-rich plasma. PMID:28829358

The "Boom" and "Bust" Patterns of Communities within the Energy Rich Region of West Virginia: A Case Study of Moundsville

NASA Astrophysics Data System (ADS)

Kiger, Brandon S.

The increasing worldwide demand for energy will provide Energy Rich Regions (ERRs) the opportunity to increase their wealth and quality of living. However, a reoccurring pattern of boom and bust cycles in ERRs suggests the need for more sustainable development strategies. A mixed methods approach (case study) is employed to explore the "wicked human problems" occurring in one community, Moundsville, WV and to discover development patterns that might inform sustainable development strategies for the future. This study explores briefly the distant past development patterns, and in greater detail the pre-boom and most current boom in natural gas. First, data will be derived from a conceptual "Energy Rich Region Template" that explores the sustainability of development from the inclusive wealth forms of natural, human, and physical capital. The qualitative data analysis software (MAXQDA) is used to systematically collect and organize data and information into a community-wide knowledge base (specifically the seven years of city council minutes). This framework can assist future research dedicated to similar cases. Furthermore, this case may support communities and or policymakers in the development of a programming guide for converting the natural capital into other reproducible capital forms, thus avoiding the development cycle of boom and bust.

Does country-context matter? A cross-national analysis of gender and leisure time physical inactivity in Europe.

PubMed

Van Tuyckom, Charlotte; Van de Velde, Sarah; Bracke, Piet

2013-06-01

It is well known that European women are less physically active in their leisure time than European men. Attempts to explain this gender difference often do not succeed in raising the problem above the individual level. However, the size of the disadvantage for women varies considerably across countries, proving that leisure time physical (in)activity takes place in a broader societal context and must also be approached as such. In this sense, some authors have explained women's lack of leisure time physical activity in terms of gendered power relations in society. Therefore, the present article postulates that over and above the individual effect of gender, there is an additional impact of a society's gender-based (in)equality distribution. By means of the 2005 Eurobarometer survey (comprising 25,745 adults from 27 European countries), gender differences in leisure time physical inactivity (LTPI) were analysed by means of multilevel logistic regression analysis. National gender-based (in)equality was measured by the Gender Empowerment Measure and the Gender Gap Index. Controlled for compositional effects, gender differences in LTPI varied as a function of gender-related characteristics at the macro-level. In particular, in countries characterized by high levels of gender-based equality, LTPI differences between men and women even disappeared. The findings underscore the need to adopt a society-level approach and to incorporate socio-contextual factors in the study of gender disparities in LTPI.

High precision optical spectroscopy and quantum state selected photodissociation of ultracold 88Sr2 molecules in an optical lattice

NASA Astrophysics Data System (ADS)

McDonald, Mickey Patrick

Over the past several decades, rapid progress has been made toward the accurate characterization and control of atoms, made possible largely by the development of narrow-linewidth lasers and techniques for trapping and cooling at ultracold temperatures. Extending this progress to molecules will have exciting implications for chemistry, condensed matter physics, and precision tests of physics beyond the Standard Model. These possibilities are all consequences of the richness of molecular structure, which is governed by physics substantially different from that characterizing atomic structure. This same richness of structure, however, increases the complexity of any molecular experiment manyfold over its atomic counterpart, magnifying the difficulty of everything from trapping and cooling to the comparison of theory with experiment. This thesis describes work performed over the past six years to establish the state of the art in manipulation and quantum control of ultracold molecules. Our molecules are produced via photoassociation of ultracold strontium atoms followed by spontaneous decay to a stable ground state. We describe a thorough set of measurements characterizing the rovibrational structure of very weakly bound (and therefore very large) 88Sr2 molecules from several different perspectives, including determinations of binding energies; linear, quadratic, and higher order Zeeman shifts; transition strengths between bound states; and lifetimes of narrow subradiant states. The physical intuition gained in these experiments applies generally to weakly bound diatomic molecules, and suggests extensive applications in precision measurement and metrology. In addition, we present a detailed analysis of the thermally broadened spectroscopic lineshape of molecules in a non-magic optical lattice trap, showing how such lineshapes can be used to directly determine the temperature of atoms or molecules in situ, addressing a long-standing problem in ultracold physics. Finally, we discuss the measurement of photofragment angular distributions produced by photodissociation, leading to an exploration of quantum-state-resolved ultracold chemistry.

Accessing resources for identity development by urban students and teachers: foregrounding context

NASA Astrophysics Data System (ADS)

Luehmann, April Lynn

2009-03-01

Many attempt to address the documented achievement gap between urban and suburban students by offering special programs to enrich urban students' academic experiences and proficiencies. Such was the case in the study described by DeGennaro and Brown in which urban students participated in an after-school technology course intended to address the "digital divide" by giving these youth supported experiences as technology users. However, also like the initial situation described in this study, instructional design that does not capitalize on what we know about urban education or informal learning contexts can actually further damage urban youths' identities as learners by positioning them as powerless and passive recipients instead of meaningful contributors to their own learning. The analysis presented in this forum is intended to further the conversation begun by DeGennaro and Brown by explicitly complexifying our consideration of context (activity structures and setting) so as to support the development of contexts that afford rich learning potential for both the urban students and their learning facilitators, positioned in the role of teachers. Carefully constructed contexts can afford participants as learners (urban students and teachers) opportunities to access rich identity resources (not typically available in traditional school contexts) including, but not limited to, the opportunity to exercise agency that allows participants to reorganize their learning context and enacted culture as needed.

Student Reasoning about Graphs in Different Contexts

ERIC Educational Resources Information Center

Ivanjek, Lana; Susac, Ana; Planinic, Maja; Andrasevic, Aneta; Milin-Sipus, Zeljka

2016-01-01

This study investigates university students' graph interpretation strategies and difficulties in mathematics, physics (kinematics), and contexts other than physics. Eight sets of parallel (isomorphic) mathematics, physics, and other context questions about graphs, which were developed by us, were administered to 385 first-year students at the…

Earth Science Contexts for Teaching Physics. Part 2: Contexts Relating to the Teaching of Energy, Earth and Beyond and Radioactivity.

ERIC Educational Resources Information Center

King, Chris; Kennett, Peter

2002-01-01

Explains how physics teaching can be more relevant for elementary and secondary students by integrating physics and earth science content that students can relate to and understand. Identifies and explains Earth contexts that can be appropriately implemented into the physics curriculum such as energy resources and radioactivity. (Author/YDS)

Binge drinking and sleep problems among young adults.

PubMed

Popovici, Ioana; French, Michael T

2013-09-01

As most of the literature exploring the relationships between alcohol use and sleep problems is descriptive and with small sample sizes, the present study seeks to provide new information on the topic by employing a large, nationally representative dataset with several waves of data and a broad set of measures for binge drinking and sleep problems. We use data from the National Longitudinal Study of Adolescent Health (Add Health), a nationally representative survey of adolescents and young adults. The analysis sample consists of all Wave 4 observations without missing values for the sleep problems variables (N=14,089, 53% females). We estimate gender-specific multivariate probit models with a rich set of socioeconomic, demographic, physical, and mental health variables to control for confounding factors. Our results confirm that alcohol use, and specifically binge drinking, is positively and significantly associated with various types of sleep problems. The detrimental effects on sleep increase in magnitude with frequency of binge drinking, suggesting a dose-response relationship. Moreover, binge drinking is associated with sleep problems independent of psychiatric conditions. The statistically strong association between sleep problems and binge drinking found in this study is a first step in understanding these relationships. Future research is needed to determine the causal links between alcohol misuse and sleep problems to inform appropriate clinical and policy responses. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Fast ray-tracing algorithm for circumstellar structures (FRACS). II. Disc parameters of the B[e] supergiant CPD-57°,2874 from VLTI/MIDI data

NASA Astrophysics Data System (ADS)

Domiciano de Souza, A.; Bendjoya, P.; Niccolini, G.; Chesneau, O.; Borges Fernandes, M.; Carciofi, A. C.; Spang, A.; Stee, P.; Driebe, T.

2011-01-01

Context. B[e] supergiants are luminous, massive post-main sequence stars exhibiting non-spherical winds, forbidden lines, and hot dust in a disc-like structure. The physical properties of their rich and complex circumstellar environment (CSE) are not well understood, partly because these CSE cannot be easily resolved at the large distances found for B[e] supergiants (typically ⪆1 kpc). Aims: From mid-IR spectro-interferometric observations obtained with VLTI/MIDI we seek to resolve and study the CSE of the Galactic B[e] supergiant CPD-57° 2874. Methods: For a physical interpretation of the observables (visibilities and spectrum) we use our ray-tracing radiative transfer code (FRACS), which is optimised for thermal spectro-interferometric observations. Results: Thanks to the short computing time required by FRACS (<10 s per monochromatic model), best-fit parameters and uncertainties for several physical quantities of CPD-57° 2874 were obtained, such as inner dust radius, relative flux contribution of the central source and of the dusty CSE, dust temperature profile, and disc inclination. Conclusions: The analysis of VLTI/MIDI data with FRACS allowed one of the first direct determinations of physical parameters of the dusty CSE of a B[e] supergiant based on interferometric data and using a full model-fitting approach. In a larger context, the study of B[e] supergiants is important for a deeper understanding of the complex structure and evolution of hot, massive stars. Based on VLTI/MIDI observations collected at the European Southern Observatory (ESO), Paranal, Chile under ESO Programmes 074.D-0101 and 078.D-0213. Also based on observations at the ESO 2.2-m telescope, La Silla, Chile, under agreement with the Observatório Nacional-MCT (Brazil).Figure 5 is only available in electronic form at http://www.aanda.org

Atmospheric waves and the nature of buoyancy turbulence in the context of the waves VS 2D-turbulence debate

NASA Technical Reports Server (NTRS)

Dewan, E. M.

1986-01-01

The problem of how to empirically distinguish between velocity fluctuations due to turbulence and those due to atmospheric waves is addressed. The physical differences between waves and turbulence are reviewed. New theoretical ideas on the subject of bouyancy range turbulence are presented. A unique scale K sub B is given that allows one to differentiate between waves and turbulence for the special case of theta = 0 (i.e., horizontal propagating waves).

Initial data sets and the topology of closed three-manifolds in general relativity

NASA Astrophysics Data System (ADS)

Carfora, M.

1983-10-01

The interaction between the matter content of a closed physical space associated with a generic gravitational configuration and the topology of the underlying closed three-manifold is discussed. Within the context of the conformal approach to the initial value problem, it is shown that the presence of enough matter and radiation favors the three-sphere topology or the worm-hole topology. It is argued that such topologies leave more room for possible gravitational initial data sets for the field equations.

Perfect relativistic magnetohydrodynamics around black holes in horizon penetrating coordinates

NASA Astrophysics Data System (ADS)

Cherubini, Christian; Filippi, Simonetta; Loppini, Alessandro; Moradi, Rahim; Ruffini, Remo; Wang, Yu; Xue, She-Sheng

2018-03-01

Plasma accreting processes on black holes represent a central problem for relativistic astrophysics. In this context, here we specifically revisit the classical Ruffini-Wilson work developed for analytically modeling via geodesic equations the accretion of perfect magnetized plasma on a rotating Kerr black hole. Introducing the horizon penetrating coordinates found by Doran 25 years later, we revisit the entire approach studying Maxwell invariants, electric and magnetic fields, volumetric charge density and electromagnetic total energy. We finally discuss the physical implications of this analysis.

Conceptual model of acid attacks based on survivor's experiences: Lessons from a qualitative exploration.

PubMed

Sabzi Khoshnami, Mohammad; Mohammadi, Elham; Addelyan Rasi, Hamideh; Khankeh, Hamid Reza; Arshi, Maliheh

2017-05-01

Acid attack, a worldwide phenomenon, has been increasing in recent years. In addition to severe injuries to the face and body, such violence leads to psychological and social problems that affect the survivors' quality of life. The present study provides a more in-depth understanding of this phenomenon and explores the nature and dimensions of acid attacks based on survivors' experiences. A grounded theory study using semi-structured, recorded interviews and applying purposeful theoretical sampling was conducted with 12 acid attack survivors in Iran. Data were analysed using constant comparison in open, axial and selective coding stages. A conceptual model was developed to explain the relationships among the main categories extracted through the grounded theory study. Physical and psychological wounds emerged as a core category. Traditional context and extreme beauty value in society acted as the context of the physical and psychological wounds experienced. Living with a drug abuser with behavioural disorders and lack of problem-solving skills in interpersonal conflict were found to be causal conditions. Action strategies to deal with this experience were found to be composed of individual, interpersonal and structural levels. Education, percentage and place of burning acted as intervening conditions that influenced survivors' strategies. Finally, adverse consequences of social deprivation and feeling helpless and hindered were found to have an important impact. Acid attack lead to physical and psychological wounds in survivors. This is a multi-dimensional phenomenon involving illness, disability, and victimization, and requires a wide range of strategies at different levels. The conceptual model derived through this study can serve as a good basis for intervention programs. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Discomfort and avoidance of touch: new insights on the emotional deficits of social anxiety.

PubMed

Kashdan, Todd B; Doorley, James; Stiksma, Melissa C; Hertenstein, Matthew J

2017-12-01

Physical touch is central to the emotional intimacy that separates romantic relationships from other social contexts. In this study of 256 adults (128 heterosexual couples, mean relationship length = 20.5 months), we examined whether individual differences in social anxiety influenced comfort with and avoidance of physical touch. Because of prior work on sex difference in touch use, touch comfort, and social anxiety symptoms and impairment, we explored sex-specific findings. We found evidence that women with greater social anxiety were less comfortable with touch and more avoidant of touch in same-sex friendships. Additionally, a woman's social anxiety had a bigger effect on a man's comfort with touch and avoidance of touch in the romantic relationship than a man's social anxiety had on the woman's endorsement of touch-related problems. These effects were uninfluenced by the length of romantic relationships. Touch is a neglected emotional experience that offers new insights into the difficulties of individuals suffering from social anxiety problems, and their romantic partners.

Test of understanding of vectors: A reliable multiple-choice vector concept test

NASA Astrophysics Data System (ADS)

Barniol, Pablo; Zavala, Genaro

2014-06-01

In this article we discuss the findings of our research on students' understanding of vector concepts in problems without physical context. First, we develop a complete taxonomy of the most frequent errors made by university students when learning vector concepts. This study is based on the results of several test administrations of open-ended problems in which a total of 2067 students participated. Using this taxonomy, we then designed a 20-item multiple-choice test [Test of understanding of vectors (TUV)] and administered it in English to 423 students who were completing the required sequence of introductory physics courses at a large private Mexican university. We evaluated the test's content validity, reliability, and discriminatory power. The results indicate that the TUV is a reliable assessment tool. We also conducted a detailed analysis of the students' understanding of the vector concepts evaluated in the test. The TUV is included in the Supplemental Material as a resource for other researchers studying vector learning, as well as instructors teaching the material.

Development of the Modes of Collaboration framework

NASA Astrophysics Data System (ADS)

Pawlak, Alanna; Irving, Paul W.; Caballero, Marcos D.

2018-01-01

Group work is becoming increasingly common in introductory physics classrooms. Understanding how students engage in these group learning environments is important for designing and facilitating productive learning opportunities for students. We conducted a study in which we collected video of groups of students working on conceptual electricity and magnetism problems in an introductory physics course. In this setting, students needed to negotiate a common understanding and coordinate group decisions in order to complete the activity successfully. We observed students interacting in several distinct ways while solving these problems. Analysis of these observations focused on identifying the different ways students interacted and articulating what defines and distinguishes them, resulting in the development of the modes of collaboration framework. The modes of collaboration framework defines student interactions along three dimensions: social, discursive, and disciplinary content. This multidimensional approach offers a unique lens through which to consider group work and provides a flexibility that could allow the framework to be adapted for a variety of contexts. We present the framework and several examples of its application here.

Carrying capacity for species richness as context for conservation: a case study of North American birds

Treesearch

Andrew J. Hansen; Linda Bowers Phillips; Curtis H. Flather; Jim Robinson-Cox

2011-01-01

We evaluated the leading hypotheses on biophysical factors affecting species richness for Breeding Bird Survey routes from areas with little influence of human activities.We then derived a best model based on information theory, and used this model to extrapolate SK across North America based on the biophysical predictor variables. The predictor variables included the...

Bad eating habits as the main cause of obesity among children.

PubMed

Kuźbicka, Karolina; Rachoń, Dominik

2013-01-01

Obesity is undoubtedly one of the biggest medical problems of the 21st century. Regrettably, the problem affects more and more children and adolescents. 10% of world's school-aged children have an excess body weight and a quarter of these children are obese. In Europe every fifth school-aged child suffers from an excess body weight. The prevalence of overweight and obesity among Polish adolescents is about 14%. An excess body weight can be the consequence of genetic factors, endocrine disorders or certain drugs. However, "simple obesity" is the most common, consequence of providing too much energy from food products in comparison to energy expenditure (caloric excess). Today's lifestyle promotes the development of obesity. The lack of physical activity, sedentary lifestyle and energy-rich diet are the main causes of an excess body fat accumulation. Because of improper eating behaviours children consume an excess amount of energy; and their diet is deficient in elements necessary for proper development. The examples of such bad eating habits are: snacking highly processed and calorie-rich foods between meals eating in front of the TV screen, skipping breakfasts, drinking sugar-sweetened beverages, "eating out" frequently and "emotional eating". Bad eating behaviours are crucial factors for the development of obesity. Eating habits are usually formed in early childhood and parents play a very important role in their development.

Comparison of University Students' Understanding of Graphs in Different Contexts

ERIC Educational Resources Information Center

Planinic, Maja; Ivanjek, Lana; Susac, Ana; Milin-Sipus, Zeljka

2013-01-01

This study investigates university students' understanding of graphs in three different domains: mathematics, physics (kinematics), and contexts other than physics. Eight sets of parallel mathematics, physics, and other context questions about graphs were developed. A test consisting of these eight sets of questions (24 questions in all) was…

Adaptive Multimedia Content Delivery for Context-Aware U-Learning

ERIC Educational Resources Information Center

Zhao, Xinyou; Okamoto, Toshio

2011-01-01

Empowered by mobile computing, teachers and students can benefit from computing in more scenarios beyond the traditional computer classroom. But because of the much diversity of device specification, learning contents and mobile context existing today, the learners get a bad learning experience (e.g. rich contents cannot be displayed correctly)…

Untangling the Intervention-Context Dyad through Horizontal Comparison: Examples from Israeli Peacebuilding Organizations

ERIC Educational Resources Information Center

Ross, Karen

2017-01-01

In this article, I argue for the importance of conducting comparative studies of educational interventions implemented within the same sociopolitical environment. Taking into account both arguments for comparative research in education and recent calls for context-rich vertical case studies, I suggest that horizontal comparisons in a single…

Conversation as a Model of Instructional Interaction

ERIC Educational Resources Information Center

Van Bramer, Joan

2003-01-01

The role of social context and the nature of human interaction provide rich resources for the study of learning and human cognition. In order to understand these elements more fully, it is important to consider the language in use within these contexts. The early intervention Reading Recovery is grounded in the belief that the conversation between…

Probing Student Understanding of Scientific Thinking in the Context of Introductory Astrophysics

ERIC Educational Resources Information Center

Steinberg, Richard N.; Cormier, Sebastien; Fernandez, Adiel

2009-01-01

Common forms of testing of student understanding of science content can be misleading about their understanding of the nature of scientific thinking. Observational astronomy integrated with related ideas of force and motion is a rich context to explore the correlation between student content knowledge and student understanding of the scientific…

Learning to Teach Elementary Science through Iterative Cycles of Enactment in Culturally and Linguistically Diverse Contexts

ERIC Educational Resources Information Center

Bottoms, SueAnn I.; Ciechanowski, Kathryn M.; Hartman, Brian

2015-01-01

Iterative cycles of enactment embedded in culturally and linguistically diverse contexts provide rich opportunities for preservice teachers (PSTs) to enact core practices of science. This study is situated in the larger Families Involved in Sociocultural Teaching and Science, Technology, Engineering and Mathematics (FIESTAS) project, which weaves…

Designing Learning Personalized to Students' Interests: Balancing Rich Experiences with Mathematical Goals

ERIC Educational Resources Information Center

Walkington, Candace; Hayata, Carole A.

2017-01-01

Context personalization is an instructional design principle where tasks are presented to students in the context of their interest areas like sports, music, or video games. Personalization allows for understanding of domain principles to be grounded in concrete and familiar experiences. By making connections to prior knowledge, personalization…

Improving Flood Predictions in Data-Scarce Basins

NASA Astrophysics Data System (ADS)

Vimal, Solomon; Zanardo, Stefano; Rafique, Farhat; Hilberts, Arno

2017-04-01

Flood modeling methodology at Risk Management Solutions Ltd. has evolved over several years with the development of continental scale flood risk models spanning most of Europe, the United States and Japan. Pluvial (rain fed) and fluvial (river fed) flood maps represent the basis for the assessment of regional flood risk. These maps are derived by solving the 1D energy balance equation for river routing and 2D shallow water equation (SWE) for overland flow. The models are run with high performance computing and GPU based solvers as the time taken for simulation is large in such continental scale modeling. These results are validated with data from authorities and business partners, and have been used in the insurance industry for many years. While this methodology has been proven extremely effective in regions where the quality and availability of data are high, its application is very challenging in other regions where data are scarce. This is generally the case for low and middle income countries, where simpler approaches are needed for flood risk modeling and assessment. In this study we explore new methods to make use of modeling results obtained in data-rich contexts to improve predictive ability in data-scarce contexts. As an example, based on our modeled flood maps in data-rich countries, we identify statistical relationships between flood characteristics and topographic and climatic indicators, and test their generalization across physical domains. Moreover, we apply the Height Above Nearest Drainage (HAND)approach to estimate "probable" saturated areas for different return period flood events as functions of basin characteristics. This work falls into the well-established research field of Predictions in Ungauged Basins.

Chemical content of the circumstellar envelope of the oxygen-rich AGB star R Doradus. Non-LTE abundance analysis of CO, SiO, and HCN

NASA Astrophysics Data System (ADS)

Van de Sande, M.; Decin, L.; Lombaert, R.; Khouri, T.; de Koter, A.; Wyrowski, F.; De Nutte, R.; Homan, W.

2018-01-01

Context. The stellar outflows of low- to intermediate-mass stars are characterised by a rich chemistry. Condensation of molecular gas species into dust grains is a key component in a chain of physical processes that leads to the onset of a stellar wind. In order to improve our understanding of the coupling between the micro-scale chemistry and macro-scale dynamics, we need to retrieve the abundance of molecules throughout the outflow. Aims: Our aim is to determine the radial abundance profile of SiO and HCN throughout the stellar outflow of R Dor, an oxygen-rich AGB star with a low mass-loss rate. SiO is thought to play an essential role in the dust-formation process of oxygen-rich AGB stars. The presence of HCN in an oxygen-rich environment is thought to be due to non-equilibrium chemistry in the inner wind. Methods: We analysed molecular transitions of CO, SiO, and HCN measured with the APEX telescope and all three instruments on the Herschel Space Observatory, together with data available in the literature. Photometric data and the infrared spectrum measured by ISO-SWS were used to constrain the dust component of the outflow. Using both continuum and line radiative transfer methods, a physical envelope model of both gas and dust was established. We performed an analysis of the SiO and HCN molecular transitions in order to calculate their abundances. Results: We have obtained an envelope model that describes the dust and the gas in the outflow, and determined the abundance of SiO and HCN throughout the region of the stellar outflow probed by our molecular data. For SiO, we find that the initial abundance lies between 5.5 × 10-5 and 6.0 × 10-5 with respect to H2. The abundance profile is constant up to 60 ± 10 R∗, after which it declines following a Gaussian profile with an e-folding radius of 3.5 ± 0.5 × 1013 cm or 1.4 ± 0.2 R∗. For HCN, we find an initial abundance of 5.0 × 10-7 with respect to H2. The Gaussian profile that describes the decline starts at the stellar surface and has an e-folding radius re of 1.85 ± 0.05 × 1015 cm or 74 ± 2 R∗. Conclusions: We cannot unambiguously identify the mechanism by which SiO is destroyed at 60 ± 10 R∗. The initial abundances found are higher than previously determined (except for one previous study on SiO), which might be due to the inclusion of higher-J transitions. The difference in abundance for SiO and HCN compared to high mass-loss rate Mira star IK Tau might be due to different pulsation characteristics of the central star and/or a difference in dust condensation physics.

Nonlinear Inference in Partially Observed Physical Systems and Deep Neural Networks

NASA Astrophysics Data System (ADS)

Rozdeba, Paul J.

The problem of model state and parameter estimation is a significant challenge in nonlinear systems. Due to practical considerations of experimental design, it is often the case that physical systems are partially observed, meaning that data is only available for a subset of the degrees of freedom required to fully model the observed system's behaviors and, ultimately, predict future observations. Estimation in this context is highly complicated by the presence of chaos, stochasticity, and measurement noise in dynamical systems. One of the aims of this dissertation is to simultaneously analyze state and parameter estimation in as a regularized inverse problem, where the introduction of a model makes it possible to reverse the forward problem of partial, noisy observation; and as a statistical inference problem using data assimilation to transfer information from measurements to the model states and parameters. Ultimately these two formulations achieve the same goal. Similar aspects that appear in both are highlighted as a means for better understanding the structure of the nonlinear inference problem. An alternative approach to data assimilation that uses model reduction is then examined as a way to eliminate unresolved nonlinear gating variables from neuron models. In this formulation, only measured variables enter into the model, and the resulting errors are themselves modeled by nonlinear stochastic processes with memory. Finally, variational annealing, a data assimilation method previously applied to dynamical systems, is introduced as a potentially useful tool for understanding deep neural network training in machine learning by exploiting similarities between the two problems.

Human behavior understanding for assisted living by means of hierarchical context free grammars

NASA Astrophysics Data System (ADS)

Rosani, A.; Conci, N.; De Natale, F. G. B.

2014-03-01

Human behavior understanding has attracted the attention of researchers in various fields over the last years. Recognizing behaviors with sufficient accuracy from sensors analysis is still an unsolved problem, because of many reasons, including the low accuracy of the data, differences in the human behaviors as well as the gap between low-level sensors data and high-level scene semantics. In this context, an application that is attracting the interest of both public and industrial entities is the possibility to allow elderly or physically impaired people conducting a normal life at home. Ambient intelligence (AmI) technologies, intended as the possibility of automatically detecting and reacting to the status of the environment and of the persons, is probably the major enabling factor for the achievement of such an ambitious objective. AmI technologies require suitable networks of sensors and actuators, as well as adequate processing and communication technologies. In this paper we propose a solution based on context free grammars for human behavior understanding with an application to assisted living. First, the grammars of the different actions performed by a person in his/her daily life are discovered. Then, a longterm analysis of the behavior is used to generate a control grammar, taking care of the context when an action is performed, and adding semantics. The proposed framework is tested on a dataset acquired in a real environment and compared with state of the art methods already available for the problem considered.

Alcohol Use Among Female Sex Workers and Male Clients: An Integrative Review of Global Literature

PubMed Central

Li, Qing; Li, Xiaoming; Stanton, Bonita

2010-01-01

Aims: To review the patterns, contexts and impacts of alcohol use associated with commercial sex reported in the global literature. Methods: We identified peer-reviewed English-language articles from 1980 to 2008 reporting alcohol consumption among female sex workers (FSWs) or male clients. We retrieved 70 articles describing 76 studies, in which 64 were quantitative (52 for FSWs, 12 for male clients) and 12 qualitative. Results: Studies increased over the past three decades, with geographic concentration of the research in Asia and North America. Alcohol use was prevalent among FSWs and clients. Integrating quantitative and qualitative studies, multilevel contexts of alcohol use in the sex work environment were identified, including workplace and occupation-related use, the use of alcohol to facilitate the transition into and practice of commercial sex among both FSWs and male clients, and self-medication among FSWs. Alcohol use was associated with adverse physical health, illicit drug use, mental health problems, and victimization of sexual violence, although its associations with HIV/sexually transmitted infections and unprotected sex among FSWs were inconclusive. Conclusions: Alcohol use in the context of commercial sex is prevalent, harmful among FSWs and male clients, but under-researched. Research in this area in more diverse settings and with standardized measures is required. The review underscores the importance of integrated intervention for alcohol use and related problems in multilevel contexts and with multiple components in order to effectively reduce alcohol use and its harmful effects among FSWs and their clients. PMID:20089544

Comparing the cognitive differences resulting from modeling instruction: Using computer microworld and physical object instruction to model real world problems

NASA Astrophysics Data System (ADS)

Oursland, Mark David

This study compared the modeling achievement of students receiving mathematical modeling instruction using the computer microworld, Interactive Physics, and students receiving instruction using physical objects. Modeling instruction included activities where students applied the (a) linear model to a variety of situations, (b) linear model to two-rate situations with a constant rate, (c) quadratic model to familiar geometric figures. Both quantitative and qualitative methods were used to analyze achievement differences between students (a) receiving different methods of modeling instruction, (b) with different levels of beginning modeling ability, or (c) with different levels of computer literacy. Student achievement was analyzed quantitatively through a three-factor analysis of variance where modeling instruction, beginning modeling ability, and computer literacy were used as the three independent factors. The SOLO (Structure of the Observed Learning Outcome) assessment framework was used to design written modeling assessment instruments to measure the students' modeling achievement. The same three independent factors were used to collect and analyze the interviews and observations of student behaviors. Both methods of modeling instruction used the data analysis approach to mathematical modeling. The instructional lessons presented problem situations where students were asked to collect data, analyze the data, write a symbolic mathematical equation, and use equation to solve the problem. The researcher recommends the following practice for modeling instruction based on the conclusions of this study. A variety of activities with a common structure are needed to make explicit the modeling process of applying a standard mathematical model. The modeling process is influenced strongly by prior knowledge of the problem context and previous modeling experiences. The conclusions of this study imply that knowledge of the properties about squares improved the students' ability to model a geometric problem more than instruction in data analysis modeling. The uses of computer microworlds such as Interactive Physics in conjunction with cooperative groups are a viable method of modeling instruction.

The turn of the screw: an exercise in protein secondary structure.

PubMed

Pikaart, Michael

2011-01-01

An exercise using simple paper strips to illustrate protein helical and sheet secondary structures is presented. Drawing on the rich historical context of the use of physical models in protein biochemistry by early practitioners, in particular Linus Pauling, the purpose of this activity is to cultivate in students a hands-on, intuitive sense of protein secondary structure and to complement the common computer-based structural portrayals often used in teaching biochemistry. As students fold these paper strips into model secondary structures, they will better grasp how intramolecular hydrogen bonds form in the folding of a polypeptide into secondary structure, and how these hydrogen bonds direct the overall shape of helical and sheet structures, including the handedness of the α-helix and the difference between right- and the left-handed twist. Copyright © 2010 Wiley Periodicals, Inc.

Quantum channels from reflections on moving mirrors.

PubMed

Gianfelici, Giulio; Mancini, Stefano

2017-11-16

Light reflection on a mirror can be thought as a simple physical effect. However if this happens when the mirror moves a rich scenario opens up. Here we aim at analyzing it from a quantum communication perspective. In particular, we study the kind of quantum channel that arises from (Gaussian) light reflection upon an accelerating mirror. Two competing mechanisms emerge in such a context, namely photons production by the mirror's motion and interference between modes. As consequence we find out a quantum amplifier channel and quantum lossy channel respectively below and above a threshold frequency (that depends on parameters determining mirror's acceleration). Exactly at the threshold frequency the channel behaves like a purely classical additive channel, while it becomes purely erasure for large frequencies. In addition the time behavior of the channel is analyzed by employing wave packets expansion of the light field.

Contribution of radiation hybrids to genome mapping in domestic animals.

PubMed

Faraut, T; de Givry, S; Hitte, C; Lahbib-Mansais, Y; Morisson, M; Milan, D; Schiex, T; Servin, B; Vignal, A; Galibert, F; Yerle, M

2009-01-01

Radiation hybrid mapping has emerged in the end of the 1990 s as a successful and complementary approach to map genomes, essentially because of its ability to bridge the gaps between genetic and clone-based physical maps, but also using comparative mapping approaches, between 'gene-rich' and 'gene-poor' maps. Since its early development in human, radiation hybrid mapping played a pivotal role in the process of mapping animal genomes, especially mammalian ones. We review here all the different steps involved in radiation hybrid mapping from the constitution of panels to the construction of maps. A description of its contribution to whole genome maps with a special emphasis on domestic animals will also be presented. Finally, current applications of radiation hybrid mapping in the context of whole genome assemblies will be described. (c) 2009 S. Karger AG, Basel.

When physics is not "just physics": complexity science invites new measurement frames for exploring the physics of cognitive and biological development.

PubMed

Kelty-Stephen, Damian; Dixon, James A

2012-01-01

The neurobiological sciences have struggled to resolve the physical foundations for biological and cognitive phenomena with a suspicion that biological and cognitive systems, capable of exhibiting and contributing to structure within themselves and through their contexts, are fundamentally distinct or autonomous from purely physical systems. Complexity science offers new physics-based approaches to explaining biological and cognitive phenomena. In response to controversy over whether complexity science might seek to "explain away" biology and cognition as "just physics," we propose that complexity science serves as an application of recent advances in physics to phenomena in biology and cognition without reducing or undermining the integrity of the phenomena to be explained. We highlight that physics is, like the neurobiological sciences, an evolving field and that the threat of reduction is overstated. We propose that distinctions between biological and cognitive systems from physical systems are pretheoretical and thus optional. We review our own work applying insights from post-classical physics regarding turbulence and fractal fluctuations to the problems of developing cognitive structure. Far from hoping to reduce biology and cognition to "nothing but" physics, we present our view that complexity science offers new explanatory frameworks for considering physical foundations of biological and cognitive phenomena.

Landscape structure affects specialists but not generalists in naturally fragmented grasslands

USGS Publications Warehouse

Miller, Jesse E.D.; Damschen, Ellen Ingman; Harrison, Susan P.; Grace, James B.

2015-01-01

Understanding how biotic communities respond to landscape spatial structure is critically important for conservation management as natural landscapes become increasingly fragmented. However, empirical studies of the effects of spatial structure on plant species richness have found inconsistent results, suggesting that more comprehensive approaches are needed. In this study, we asked how landscape structure affects total plant species richness and the richness of a guild of specialized plants in a multivariate context. We sampled herbaceous plant communities at 56 dolomite glades (insular, fire-adapted grasslands) across the Missouri Ozarks, and used structural equation modeling (SEM) to analyze the relative importance of landscape structure, soil resource availability, and fire history for plant communities. We found that landscape spatial structure-defined as the area-weighted proximity of glade habitat surrounding study sites (proximity index)-had a significant effect on total plant species richness, but only after we controlled for environmental covariates. Richness of specialist species, but not generalists, was positively related to landscape spatial structure. Our results highlight that local environmental filters must be considered to understand the influence of landscape structure on communities, and that unique species guilds may respond differently to landscape structure than the community as a whole. These findings suggest that both local environment and landscape context should be considered when developing management strategies for species of conservation concern in fragmented habitats.

The application of statistical mechanics on the study of glassy behaviors in transportation networks and dynamics in models of financial markets

NASA Astrophysics Data System (ADS)

Yeung, Chi Ho

In this thesis, we study two interdisciplinary problems in the framework of statistical physics, which show the broad applicability of physics on problems with various origins. The first problem corresponds to an optimization problem in allocating resources on random regular networks. Frustrations arise from competition for resources. When the initial resources are uniform, different regimes with discrete fractions of satisfied nodes are observed, resembling the Devil's staircase. We apply the spin glass theory in analyses and demonstrate how functional recursions are converted to simple recursions of probabilities. Equilibrium properties such as the average energy and the fraction of free nodes are derived. When the initial resources are bimodally distributed, increases in the fraction of rich nodes induce a glassy transition, entering a glassy phase described by the existence of multiple metastable states, in which we employ the replica symmetry breaking ansatz for analysis. The second problem corresponds to the study of multi-agent systems modeling financial markets. Agents in the system trade among themselves, and self-organize to produce macroscopic trading behaviors resembling the real financial markets. These behaviors include the arbitraging activities, the setting up and the following of price trends. A phase diagram of these behaviors is obtained, as a function of the sensitivity of price and the market impact factor. We finally test the applicability of the models with real financial data including the Hang Seng Index, the Nasdaq Composite and the Dow Jones Industrial Average. A substantial fraction of agents gains faster than the inflation rate of the indices, suggesting the possibility of using multi-agent systems as a tool for real trading.

Analysis of Anderson Acceleration on a Simplified Neutronics/Thermal Hydraulics System

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

Toth, Alex; Kelley, C. T.; Slattery, Stuart R

ABSTRACT A standard method for solving coupled multiphysics problems in light water reactors is Picard iteration, which sequentially alternates between solving single physics applications. This solution approach is appealing due to simplicity of implementation and the ability to leverage existing software packages to accurately solve single physics applications. However, there are several drawbacks in the convergence behavior of this method; namely slow convergence and the necessity of heuristically chosen damping factors to achieve convergence in many cases. Anderson acceleration is a method that has been seen to be more robust and fast converging than Picard iteration for many problems, withoutmore » significantly higher cost per iteration or complexity of implementation, though its effectiveness in the context of multiphysics coupling is not well explored. In this work, we develop a one-dimensional model simulating the coupling between the neutron distribution and fuel and coolant properties in a single fuel pin. We show that this model generally captures the convergence issues noted in Picard iterations which couple high-fidelity physics codes. We then use this model to gauge potential improvements with regard to rate of convergence and robustness from utilizing Anderson acceleration as an alternative to Picard iteration.« less

Size Distributions of Solar Proton Events: Methodological and Physical Restrictions

NASA Astrophysics Data System (ADS)

Miroshnichenko, L. I.; Yanke, V. G.

2016-12-01

Based on the new catalogue of solar proton events (SPEs) for the period of 1997 - 2009 (Solar Cycle 23) we revisit the long-studied problem of the event-size distributions in the context of those constructed for other solar-flare parameters. Recent results on the problem of size distributions of solar flares and proton events are briefly reviewed. Even a cursory acquaintance with this research field reveals a rather mixed and controversial picture. We concentrate on three main issues: i) SPE size distribution for {>} 10 MeV protons in Solar Cycle 23; ii) size distribution of {>} 1 GV proton events in 1942 - 2014; iii) variations of annual numbers for {>} 10 MeV proton events on long time scales (1955 - 2015). Different results are critically compared; most of the studies in this field are shown to suffer from vastly different input datasets as well as from insufficient knowledge of underlying physical processes in the SPEs under consideration. New studies in this field should be made on more distinct physical and methodological bases. It is important to note the evident similarity in size distributions of solar flares and superflares in Sun-like stars.

Towards a richer evolutionary game theory

PubMed Central

McNamara, John M.

2013-01-01

Most examples of the application of evolutionary game theory to problems in biology involve highly simplified models. I contend that it is time to move on and include much more richness in models. In particular, more thought needs to be given to the importance of (i) between-individual variation; (ii) the interaction between individuals, and hence the process by which decisions are reached; (iii) the ecological and life-history context of the situation; (iv) the traits that are under selection, and (v) the underlying psychological mechanisms that lead to behaviour. I give examples where including variation between individuals fundamentally changes predicted outcomes of a game. Variation also selects for real-time responses, again resulting in changed outcomes. Variation can select for other traits, such as choosiness and social sensitivity. More generally, many problems involve coevolution of more than one trait. I identify situations where a reductionist approach, in which a game is isolated from is ecological setting, can be misleading. I also highlight the need to consider flexibility of behaviour, mental states and other issues concerned with the evolution of mechanism. PMID:23966616

Functional richness: Overview of indices and underlying concepts

NASA Astrophysics Data System (ADS)

Legras, G.; Loiseau, N.; Gaertner, J.-C.

2018-02-01

Functional richness, currently defined as the amount of niche space occupied by the species within a community, is one of the three major components of functional diversity. Different indices have been developed in order to quantify this component. However, the range of indices available for assessing functional richness, often mathematically complex and based on different rationales, can cause confusion for field ecologists and lead to misinterpretation of the results obtained. In this context, we have provided the first study exclusively focused on the comparison of the definitions, advantages and drawbacks of a large set of functional richness indices. The first part of this work is focused on four indices (FDP&G, FRic, TOP and N-hypervolumes indices) that are currently the most commonly used for assessing functional richness. We have completed our study by including recently developed indices that enable us to take into account the intraspecific trait variability (i.e. FRim index and TDP framework), because there is currently a growing scientific consensus regarding the necessity of including this aspect in the assessment of the functional diversity of communities. We demonstrate that although authors have argued that their index describes the functional richness, each of them describes only part of it, and this part may strongly differ from one index to another. Rather than advocating the general use of a single index and/or systematically avoiding others, our study highlights the need for selecting indices in close relation with the context, the available data and the aims of each study. Such a strategy is an essential preliminary step for preventing misunderstanding and artefactual controversies. Along these lines, we propose some guidelines to help users in selecting the most appropriate indices according both to the facet of functional richness on which they wish to focus and to the characteristics of the available data.

The Volumetric Rate of Calcium-rich Transients in the Local Universe

DOE PAGES

Frohmaier, Chris; Sullivan, Mark; Maguire, Kate; ...

2018-05-04

Here, we present a measurement of the volumetric rate of "calcium-rich" optical transients in the local universe, using a sample of three events from the Palomar Transient Factory (PTF). This measurement builds on a detailed study of the PTF transient detection efficiencies and uses a Monte Carlo simulation of the PTF survey. We measure the volumetric rate of calcium-rich transients to be higher than previous estimates: 1.21 -0.39 +1.13 10 -5 events yr -1Mpc -3. This is equivalent to 33%-94% of the local volumetric Type Ia supernova rate. This calcium-rich transient rate is sufficient to reproduce the observed calcium abundancesmore » in galaxy clusters, assuming an asymptotic calcium yield per calcium-rich event of ~0.05 M ⊙. As a result, we also study the PTF detection efficiency of these transients as a function of position within their candidate host galaxies. We confirm as a real physical effect previous results that suggest that calcium-rich transients prefer large physical offsets from their host galaxies.« less

The Volumetric Rate of Calcium-rich Transients in the Local Universe

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

Frohmaier, Chris; Sullivan, Mark; Maguire, Kate

Here, we present a measurement of the volumetric rate of "calcium-rich" optical transients in the local universe, using a sample of three events from the Palomar Transient Factory (PTF). This measurement builds on a detailed study of the PTF transient detection efficiencies and uses a Monte Carlo simulation of the PTF survey. We measure the volumetric rate of calcium-rich transients to be higher than previous estimates: 1.21 -0.39 +1.13 10 -5 events yr -1Mpc -3. This is equivalent to 33%-94% of the local volumetric Type Ia supernova rate. This calcium-rich transient rate is sufficient to reproduce the observed calcium abundancesmore » in galaxy clusters, assuming an asymptotic calcium yield per calcium-rich event of ~0.05 M ⊙. As a result, we also study the PTF detection efficiency of these transients as a function of position within their candidate host galaxies. We confirm as a real physical effect previous results that suggest that calcium-rich transients prefer large physical offsets from their host galaxies.« less

An evolving perspective on physical activity counselling by medical professionals

PubMed Central

2012-01-01

Background Physical inactivity is a modifiable risk factor for many chronic conditions and a leading cause of premature mortality. An increasing proportion of adults worldwide are not engaging in a level of physical activity sufficient to prevent or alleviate these adverse effects. Medical professionals have been identified as potentially powerful sources of influence for those who do not meet minimum physical activity guidelines. Health professionals are respected and expected sources of advice and they reach a large and relevant proportion of the population. Despite this potential, health professionals are not routinely practicing physical activity promotion. Discussion Medical professionals experience several known barriers to physical activity promotion including lack of time and lack of perceived efficacy in changing physical activity behaviour in patients. Furthermore, evidence for effective physical activity promotion by medical professionals is inconclusive. To address these problems, new approaches to physical activity promotion are being proposed. These include collaborating with community based physical activity behaviour change interventions, preparing patients for effective brief counselling during a consultation with the medical professional, and use of interactive behaviour change technology. Summary It is important that we recognise the latent risk of physical inactivity among patients presenting in clinical settings. Preparation for improving patient physical activity behaviours should commence before the consultation and may include physical activity screening. Medical professionals should also identify suitable community interventions to which they can refer physically inactive patients. Outsourcing the majority of a comprehensive physical activity intervention to community based interventions will reduce the required clinical consultation time for addressing the issue with each patient. Priorities for future research include investigating ways to promote successful referrals and subsequent engagement in comprehensive community support programs to increase physical activity levels of inactive patients. Additionally, future clinical trials of physical activity interventions should be evaluated in the context of a broader framework of outcomes to inform a systematic consideration of broad strengths and weaknesses regarding not only efficacy but cost-effectiveness and likelihood of successful translation of interventions to clinical contexts. PMID:22524484

Sophisticated epistemologies of physics versus high-stakes tests: How do elite high school students respond to competing influences about how to learn physics?

NASA Astrophysics Data System (ADS)

Yerdelen-Damar, Sevda; Elby, Andrew

2016-06-01

This study investigates how elite Turkish high school physics students claim to approach learning physics when they are simultaneously (i) engaged in a curriculum that led to significant gains in their epistemological sophistication and (ii) subject to a high-stakes college entrance exam. Students reported taking surface (rote) approaches to learning physics, largely driven by college entrance exam preparation and therefore focused on algorithmic problem solving at the expense of exploring concepts and real-life examples more deeply. By contrast, in recommending study strategies to "Arzu," a hypothetical student who doesn't need to take a college entrance exam and just wants to understand physics deeply, the students focused more on linking concepts and real-life examples and on making sense of the formulas and concepts—deep approaches to learning that reflect somewhat sophisticated epistemologies. These results illustrate how students can epistemically compartmentalize, consciously taking different epistemic stances—different views of what counts as knowing and learning—in different contexts even within the same discipline.

Province-level income inequality and health outcomes in Canadian adolescents.

PubMed

Quon, Elizabeth C; McGrath, Jennifer J

2015-03-01

To examine the effects of provincial income inequality (disparity between rich and poor), independent of provincial income and family socioeconomic status, on multiple adolescent health outcomes. Participants (aged 12-17 years; N = 11,899) were from the Canadian National Longitudinal Survey of Children and Youth. Parental education, household income, province income inequality, and province mean income were measured. Health outcomes were measured across a number of domains, including self-rated health, mental health, health behaviors, substance use behaviors, and physical health. Income inequality was associated with injuries, general physical symptoms, and limiting conditions, but not associated with most adolescent health outcomes and behaviors. Income inequality had a moderating effect on family socioeconomic status for limiting conditions, hyperactivity/inattention, and conduct problems, but not for other outcomes. Province-level income inequality was associated with some physical and mental health outcomes in adolescents, which has research and policy implications for this age-group. © The Author 2014. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

DEEP MIXING IN EVOLVED STARS. II. INTERPRETING Li ABUNDANCES IN RED GIANT BRANCH AND ASYMPTOTIC GIANT BRANCH STARS

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

Palmerini, S.; Busso, M.; Maiorca, E.

2011-11-01

We reanalyze the problem of Li abundances in red giants of nearly solar metallicity. After outlining the problems affecting our knowledge of the Li content in low-mass stars (M {<=} 3 M{sub sun}), we discuss deep-mixing models for the red giant branch stages suitable to account for the observed trends and for the correlated variations of the carbon isotope ratio; we find that Li destruction in these phases is limited to masses below about 2.3 M{sub sun}. Subsequently, we concentrate on the final stages of evolution for both O-rich and C-rich asymptotic giant branch (AGB) stars. Here, the constraints onmore » extra-mixing phenomena previously derived from heavier nuclei (from C to Al), coupled to recent updates in stellar structure models (including both the input physics and the set of reaction rates used), are suitable to account for the observations of Li abundances below A(Li) {identical_to} log {epsilon}(Li) {approx_equal} 1.5 (and sometimes more). Also, their relations with other nucleosynthesis signatures of AGB phases (like the abundance of F, and the C/O and {sup 12}C/{sup 13}C ratios) can be explained. This requires generally moderate efficiencies (M-dot < or approx. 0.3-0.5 x 10{sup -6} M{sub sun} yr{sup -1}) for non-convective mass transport. At such rates, slow extra mixing does not remarkably modify Li abundances in early AGB phases; on the other hand, faster mixing encounters a physical limit in destroying Li, set by the mixing velocity. Beyond this limit, Li starts to be produced; therefore, its destruction on the AGB is modest. Li is then significantly produced by the third dredge up. We also show that effective circulation episodes, while not destroying Li, would easily bring the {sup 12}C/{sup 13}C ratios to equilibrium, contrary to the evidence in most AGB stars, and would burn F beyond the limits shown by C(N) giants. Hence, we do not confirm the common idea that efficient extra mixing drastically reduces the Li content of C stars with respect to K-M giants. This misleading appearance is induced by biases in the data, namely: (1) the difficulty of measuring very low Li abundances in O-rich AGB stars due to the presence of TiO bands and (2) the fact that many, relatively massive (M > 3 M{sub sun}) K- and M-type giants may remain Li-rich, not evolving to the C-rich stages. Efficient extra mixing on the AGB is instead typical of very low masses (M {approx}< 1.5 M{sub sun}). It also characterizes CJ stars, where it produces Li and reduces F and the carbon isotope ratio, as observed in these peculiar objects.« less

Design and R&D of RICH detectors for EIC experiments

NASA Astrophysics Data System (ADS)

Del Dotto, A.; Wong, C.-P.; Allison, L.; Awadi, M.; Azmoun, B.; Barbosa, F.; Brooks, W.; Cao, T.; Chiu, M.; Cisbani, E.; Contalbrigo, M.; Datta, A.; Demarteau, M.; Durham, J. M.; Dzhygadlo, R.; Fields, D.; Furletova, Y.; Gleason, C.; Grosse-Perdekamp, M.; Harris, J.; He, X.; van Hecke, H.; Horn, T.; Huang, J.; Hyde, C.; Ilieva, Y.; Kalicy, G.; Kimball, M.; Kistenev, E.; Kulinich, Y.; Liu, M.; Majka, R.; McKisson, J.; Mendez, R.; Nadel-Turonski, P.; Park, K.; Peters, K.; Rao, T.; Pisani, R.; Qiang, Y.; Rescia, S.; Rossi, P.; Sarsour, M.; Schwarz, C.; Schwiening, J.; da Silva, C. L.; Smirnov, N.; Stein, H.; Stevens, J.; Sukhanov, A.; Syed, S.; Tate, A.; Toh, J.; Towell, C.; Towell, R.; Tsang, T.; Wagner, R.; Wang, J.; Woody, C.; Xi, W.; Xie, J.; Zhao, Z. W.; Zihlmann, B.; Zorn, C.

2017-12-01

An Electron-Ion Collider (EIC) has been proposed to further explore the strong force and QCD, focusing on the structure and the interaction of gluon-dominated matter. A generic detector R&D program (EIC PID consortium) for the particle identification in EIC experiments was formed to explore technologically advanced solutions in this scope. In this context two Ring Imaging Cherenkov (RICH) counters have been proposed: a modular RICH detector which consists of an aerogel radiator, a Fresnel lens, a mirrored box, and pixelated photon sensor; a dual-radiator RICH, consisting of an aerogel radiator and C2F6 gas in a mirror-focused configuration. We present the simulations of the two detectors and their estimated performance.

Statistical mechanics of complex neural systems and high dimensional data

NASA Astrophysics Data System (ADS)

Advani, Madhu; Lahiri, Subhaneil; Ganguli, Surya

2013-03-01

Recent experimental advances in neuroscience have opened new vistas into the immense complexity of neuronal networks. This proliferation of data challenges us on two parallel fronts. First, how can we form adequate theoretical frameworks for understanding how dynamical network processes cooperate across widely disparate spatiotemporal scales to solve important computational problems? Second, how can we extract meaningful models of neuronal systems from high dimensional datasets? To aid in these challenges, we give a pedagogical review of a collection of ideas and theoretical methods arising at the intersection of statistical physics, computer science and neurobiology. We introduce the interrelated replica and cavity methods, which originated in statistical physics as powerful ways to quantitatively analyze large highly heterogeneous systems of many interacting degrees of freedom. We also introduce the closely related notion of message passing in graphical models, which originated in computer science as a distributed algorithm capable of solving large inference and optimization problems involving many coupled variables. We then show how both the statistical physics and computer science perspectives can be applied in a wide diversity of contexts to problems arising in theoretical neuroscience and data analysis. Along the way we discuss spin glasses, learning theory, illusions of structure in noise, random matrices, dimensionality reduction and compressed sensing, all within the unified formalism of the replica method. Moreover, we review recent conceptual connections between message passing in graphical models, and neural computation and learning. Overall, these ideas illustrate how statistical physics and computer science might provide a lens through which we can uncover emergent computational functions buried deep within the dynamical complexities of neuronal networks.

Stabilized FE simulation of prototype thermal-hydraulics problems with integrated adjoint-based capabilities

NASA Astrophysics Data System (ADS)

Shadid, J. N.; Smith, T. M.; Cyr, E. C.; Wildey, T. M.; Pawlowski, R. P.

2016-09-01

A critical aspect of applying modern computational solution methods to complex multiphysics systems of relevance to nuclear reactor modeling, is the assessment of the predictive capability of specific proposed mathematical models. In this respect the understanding of numerical error, the sensitivity of the solution to parameters associated with input data, boundary condition uncertainty, and mathematical models is critical. Additionally, the ability to evaluate and or approximate the model efficiently, to allow development of a reasonable level of statistical diagnostics of the mathematical model and the physical system, is of central importance. In this study we report on initial efforts to apply integrated adjoint-based computational analysis and automatic differentiation tools to begin to address these issues. The study is carried out in the context of a Reynolds averaged Navier-Stokes approximation to turbulent fluid flow and heat transfer using a particular spatial discretization based on implicit fully-coupled stabilized FE methods. Initial results are presented that show the promise of these computational techniques in the context of nuclear reactor relevant prototype thermal-hydraulics problems.

Stabilized FE simulation of prototype thermal-hydraulics problems with integrated adjoint-based capabilities

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

Shadid, J.N., E-mail: jnshadi@sandia.gov; Department of Mathematics and Statistics, University of New Mexico; Smith, T.M.

A critical aspect of applying modern computational solution methods to complex multiphysics systems of relevance to nuclear reactor modeling, is the assessment of the predictive capability of specific proposed mathematical models. In this respect the understanding of numerical error, the sensitivity of the solution to parameters associated with input data, boundary condition uncertainty, and mathematical models is critical. Additionally, the ability to evaluate and or approximate the model efficiently, to allow development of a reasonable level of statistical diagnostics of the mathematical model and the physical system, is of central importance. In this study we report on initial efforts tomore » apply integrated adjoint-based computational analysis and automatic differentiation tools to begin to address these issues. The study is carried out in the context of a Reynolds averaged Navier–Stokes approximation to turbulent fluid flow and heat transfer using a particular spatial discretization based on implicit fully-coupled stabilized FE methods. Initial results are presented that show the promise of these computational techniques in the context of nuclear reactor relevant prototype thermal-hydraulics problems.« less

Stabilized FE simulation of prototype thermal-hydraulics problems with integrated adjoint-based capabilities

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

Shadid, J. N.; Smith, T. M.; Cyr, E. C.

A critical aspect of applying modern computational solution methods to complex multiphysics systems of relevance to nuclear reactor modeling, is the assessment of the predictive capability of specific proposed mathematical models. The understanding of numerical error, the sensitivity of the solution to parameters associated with input data, boundary condition uncertainty, and mathematical models is critical. Additionally, the ability to evaluate and or approximate the model efficiently, to allow development of a reasonable level of statistical diagnostics of the mathematical model and the physical system, is of central importance. In our study we report on initial efforts to apply integrated adjoint-basedmore » computational analysis and automatic differentiation tools to begin to address these issues. The study is carried out in the context of a Reynolds averaged Navier–Stokes approximation to turbulent fluid flow and heat transfer using a particular spatial discretization based on implicit fully-coupled stabilized FE methods. We present the initial results that show the promise of these computational techniques in the context of nuclear reactor relevant prototype thermal-hydraulics problems.« less

Stabilized FE simulation of prototype thermal-hydraulics problems with integrated adjoint-based capabilities

DOE PAGES

Shadid, J. N.; Smith, T. M.; Cyr, E. C.; ...

2016-05-20

A critical aspect of applying modern computational solution methods to complex multiphysics systems of relevance to nuclear reactor modeling, is the assessment of the predictive capability of specific proposed mathematical models. The understanding of numerical error, the sensitivity of the solution to parameters associated with input data, boundary condition uncertainty, and mathematical models is critical. Additionally, the ability to evaluate and or approximate the model efficiently, to allow development of a reasonable level of statistical diagnostics of the mathematical model and the physical system, is of central importance. In our study we report on initial efforts to apply integrated adjoint-basedmore » computational analysis and automatic differentiation tools to begin to address these issues. The study is carried out in the context of a Reynolds averaged Navier–Stokes approximation to turbulent fluid flow and heat transfer using a particular spatial discretization based on implicit fully-coupled stabilized FE methods. We present the initial results that show the promise of these computational techniques in the context of nuclear reactor relevant prototype thermal-hydraulics problems.« less

α-induced reaction cross section measurements on 197Au

NASA Astrophysics Data System (ADS)

Szücs, Tamás; Gyürky, György; Halász, Zoltán; Kiss, Gábor Gy.; Fülöp, Zsolt

2018-01-01

The γ-process is responsible for creating the majority of the isotopes of heavier elements on the proton rich side of the valley of stability. The γ-process simulations fail to reproduce the measured solar system abundance of these isotopes. The problem can lie in the not well known astrophysical scenarios where the process takes place, or in the not sufficiently known nuclear physics input. To improve the latter part, α-induced reaction cross section measurements on 197Au were carried out at Atomki. With this dataset new experimental information will become available, which can be later used as validation of the theoretical cross section calculations used in the γ-process simulations.

Design of physical and logical topologies with fault-tolerant ability in wavelength-routed optical network

NASA Astrophysics Data System (ADS)

Chen, Chunfeng; Liu, Hua; Fan, Ge

2005-02-01

In this paper we consider the problem of designing a network of optical cross-connects(OXCs) to provide end-to-end lightpath services to label switched routers (LSRs). Like some previous work, we select the number of OXCs as our objective. Compared with the previous studies, we take into account the fault-tolerant characteristic of logical topology. First of all, using a Prufer number randomly generated, we generate a tree. By adding some edges to the tree, we can obtain a physical topology which consists of a certain number of OXCs and fiber links connecting OXCs. It is notable that we for the first time limit the number of layers of the tree produced according to the method mentioned above. Then we design the logical topologies based on the physical topologies mentioned above. In principle, we will select the shortest path in addition to some consideration on the load balancing of links and the limitation owing to the SRLG. Notably, we implement the routing algorithm for the nodes in increasing order of the degree of the nodes. With regarding to the problem of the wavelength assignment, we adopt the heuristic algorithm of the graph coloring commonly used. It is clear our problem is computationally intractable especially when the scale of the network is large. We adopt the taboo search algorithm to find the near optimal solution to our objective. We present numerical results for up to 1000 LSRs and for a wide range of system parameters such as the number of wavelengths supported by each fiber link and traffic. The results indicate that it is possible to build large-scale optical networks with rich connectivity in a cost-effective manner, using relatively few but properly dimensioned OXCs.

Muon Physics at the Paul Scherrer Institut (psi) and at Triumf

NASA Astrophysics Data System (ADS)

Walter, Hans-Kristian

Muons can be produced abundantly at so-called pion factories. Fundamental information about todays standard model of particle physics is obtained by studying their decays. New experiments have been proposed at PSI and TRIUMF to measure the muons lifetime, the Michel parameters, describing its main decay μ+ → e+ + ve + ` vμ, as well as the decay positrons polarizations. Muon and electron number violating decays like μ+ → e+ + γ and neutrinoless muon electron conversion in nuclei μ- N → e- N are especially sensitive to new physics beyond the standard model. The moon when bound in a muonic atom or to an electron to form muonium, can also serve as a tool to investigate properties of its binding partner and the electroweak binding forces. Muonic and pionic hydrogen isotopes and Helium are mostly being studied. Finally muons can be applied to address problems in solid state and surface physics. Here cold and ultracold muons are of special interest, because of their very small phase space. Muon catalyzed fusion in addtition to offering a rich field for atomic and molecular physics could be used in technological applications like energy production (in connection with conventional breeders) or to construct a strong source of 14 MeV neutrons.

Two-Body Approximations in the Design of Low-Energy Transfers Between Galilean Moons

NASA Astrophysics Data System (ADS)

Fantino, Elena; Castelli, Roberto

Over the past two decades, the robotic exploration of the Solar System has reached the moons of the giant planets. In the case of Jupiter, a strong scientific interest towards its icy moons has motivated important space missions (e.g., ESAs' JUICE and NASA's Europa Mission). A major issue in this context is the design of efficient trajectories enabling satellite tours, i.e., visiting the several moons in succession. Concepts like the Petit Grand Tour and the Multi-Moon Orbiter have been developed to this purpose, and the literature on the subject is quite rich. The models adopted are the two-body problem (with the patched conics approximation and gravity assists) and the three-body problem (giving rise to the so-called low-energy transfers, LETs). In this contribution, we deal with the connection between two moons, Europa and Ganymede, and we investigate a two-body approximation of trajectories originating from the stable/unstable invariant manifolds of the two circular restricted three body problems, i.e., Jupiter-Ganymede and Jupiter-Europa. We develop ad-hoc algorithms to determine the intersections of the resulting elliptical arcs, and the magnitude of the maneuver at the intersections. We provide a means to perform very fast and accurate evaluations of the minimum-cost trajectories between the two moons. Eventually, we validate the methodology by comparison with numerical integrations in the three-body problem.

The Volumetric Rate of Calcium-rich Transients in the Local Universe

NASA Astrophysics Data System (ADS)

Frohmaier, Chris; Sullivan, Mark; Maguire, Kate; Nugent, Peter

2018-05-01

We present a measurement of the volumetric rate of “calcium-rich” optical transients in the local universe, using a sample of three events from the Palomar Transient Factory (PTF). This measurement builds on a detailed study of the PTF transient detection efficiencies and uses a Monte Carlo simulation of the PTF survey. We measure the volumetric rate of calcium-rich transients to be higher than previous estimates: {1.21}-0.39+1.13 × {10}-5 events yr‑1 Mpc‑3. This is equivalent to 33%–94% of the local volumetric Type Ia supernova rate. This calcium-rich transient rate is sufficient to reproduce the observed calcium abundances in galaxy clusters, assuming an asymptotic calcium yield per calcium-rich event of ∼0.05 {M}ȯ . We also study the PTF detection efficiency of these transients as a function of position within their candidate host galaxies. We confirm as a real physical effect previous results that suggest that calcium-rich transients prefer large physical offsets from their host galaxies.

Social Context of Drinking and Alcohol Problems among College Students

ERIC Educational Resources Information Center

Beck, Kenneth H.; Arria, Amelia M.; Caldeira, Kimberly M.; Vincent, Kathryn B.; O'Grady, Kevin E.; Wish, Eric D.

2008-01-01

Objective: To examine how social contexts of drinking are related to alcohol use disorders, other alcohol-related problems, and depression among college students. Methods: Logistic regression models controlling for drinking frequency measured the association between social context and problems, among 728 current drinkers. Results: Drinking for…

Performance of the LHCb RICH detectors during the LHC Run II

NASA Astrophysics Data System (ADS)

Papanestis, A.; D'Ambrosio, C.; LHCb RICH Collaboration

2017-12-01

The LHCb RICH system provides hadron identification over a wide momentum range (2-100 GeV/c). This detector system is key to LHCb's precision flavour physics programme, which has unique sensitivity to physics beyond the standard model. This paper reports on the performance of the LHCb RICH in Run II, following significant changes in the detector and operating conditions. The changes include the refurbishment of significant number of photon detectors, assembled using new vacuum technologies, and the removal of the aerogel radiator. The start of Run II of the LHC saw the beam energy increase to 6.5 TeV per beam and a new trigger strategy for LHCb with full online detector calibration. The RICH information has also been made available for all trigger streams in the High Level Trigger for the first time.

The Design and Development of a Context-Rich, Photo-Based Online Testing to Assess Students' Science Learning

ERIC Educational Resources Information Center

Lin, Min-Jin; Guo, Chorng-Jee; Hsu, Chia-Er

2011-01-01

This study designed and developed a CP-MCT (content-rich, photo-based multiple choice online test) to assess whether college students can apply the basic light concept to interpret daily light phenomena. One hundred college students volunteered to take the CP-MCT, and the results were statistically analyzed by applying t-test or ANOVA (Analysis of…

Investigating Variation in Teaching with Technology-Rich Intervention: What Matters in Teaching and Teacher Training at Scale?

ERIC Educational Resources Information Center

Dunn, Margaret Breslin

2009-01-01

A main question this dissertation addresses is: what variation in teaching and teacher training matter? This question is examined within a specific but important context: the scale-up of a technology-rich intervention focused on the algebra strand of 8th grade mathematics. I conducted a multi-level case study by gathering and analyzing data at…

Unwanted Sexual Experiences in Young Men: Evidence from a Survey of University Students in Chile

PubMed Central

Lehrer, Jocelyn A.; Lehrer, Evelyn L.; Koss, Mary P.

2012-01-01

The public health problem of unwanted sexual experiences (USE) in male youths has received little attention. In this study, we examined prevalence of USE, risk factors, contexts, and barriers to disclosure with data from a quantitative survey of students enrolled in General Education courses at a public university in Chile. This study focused on the male sample (N = 466). Approximately 20.4% of participants reported some form of USE since age 14. Forced sex through physical coercion, forced sex through verbal coercion or while intoxicated, attempted forced sex, and less severe forms of USE were reported by 0.2%, 10.1%, 1.4%, and 8.7% of participants, respectively. USE before age 14 was reported by 9.4% of participants and was a significant predictor of USE since age 14 (AOR 6.38, 95% CI 3.22–12.65, p < .01). The perpetrator of USE since age 14 was most commonly identified as a date/partner or friend/acquaintance; other findings on contexts and barriers to disclosure were also generally consistent with previous results in the literature. In addition, we found substantial co-occurrence of USE since age 14 with two other forms of coercion: physical dating violence victimization and coerced condom non-use. The study findings indicate a need for further attention to these public health problems and have implications for the development of violence and HIV/STI prevention programs for adolescent boys and young adult men in Chile and elsewhere. PMID:22971801

A Framework for Rebuilding Initial Certification and Preparation Programs in Educational Leadership: Lessons from Whole-State Reform Initiatives

ERIC Educational Resources Information Center

Murphy, Joseph; Moorman, Hunter N.; McCarthy, Martha

2008-01-01

Background/Context: This study examines the extent of reform in preparation programs in school leadership in six states employing a comprehensive, whole-state intervention design. Although no studies of these or other comprehensive reform designs are available, there is a rich context surrounding preparation reform work that informed our…

Imagination and the Cognitive Tools of Place-Making

ERIC Educational Resources Information Center

Fettes, Mark; Judson, Gillian

2011-01-01

In environmental and ecological education, a rich literature builds on the premise that place, the local natural context in which one lives, can be an emotionally engaging context for learning and the source of life-long concern for nature. A theory of imaginative education can help uncover new tools and strategies for place-based educators.…

Computational procedures for mixed equations with shock waves

NASA Technical Reports Server (NTRS)

Yu, N. J.; Seebass, R.

1974-01-01

This paper discusses the procedures we have developed to treat a canonical problem involving a mixed nonlinear equation with boundary data that imply a discontinuous solution. This equation arises in various physical contexts and is basic to the description of the nonlinear acoustic behavior of a shock wave near a caustic. The numerical scheme developed is of second order, treats discontinuities as such by applying the appropriate jump conditions across them, and eliminates the numerical dissipation and dispersion associated with large gradients. Our results are compared with the results of a first-order scheme and with those of a second-order scheme we have developed. The algorithm used here can easily be generalized to more complicated problems, including transonic flows with imbedded shocks.

What We Don't Understand About Ion Acceleration Flares

NASA Technical Reports Server (NTRS)

Reames, Donald V.; Ng, C. K.; Tylka, A. J.

1999-01-01

There are now strong associations between the (3)He-rich, Fe-rich ions in "impulsive" solar energetic particle (SEP) events and the similar abundances derived from gamma-ray lines from flares. Compact flares, where wave energy can predominate, are ideal sites for the study of wave-particle physics. Yet there are nagging questions about the magnetic geometry, the relation between ions that escape and those that interact, and the relative roles of cascading Alfven waves and the EMIC waves required to enhance He-3. There are also questions about the relative timing of ion and electron acceleration and of heating; these relate to the variation of ionization states before and during acceleration and during transport out of the corona. We can construct a model that addresses many of these issues, but problems do remain. Our greatest lack is realistic theoretical simulations of element abundances, spectra, and their variations. By contrast, we now have a much better idea of the acceleration at CME-driven shock waves in the rare but large "gradual" SEP events, largely because of their slow temporal evolution and great spatial extent.

Merging of a CO WD and a He-rich WD to produce a type Ia supernovae

NASA Astrophysics Data System (ADS)

Liu, D.; Wang, B.; Wu, C.; Han, Z.

2017-10-01

Context. Although type Ia supernovae (SNe Ia) play a key role in astrophysics, the companions of the exploding carbon-oxygen white dwarfs (CO WDs) are still not completely identified. It has been suggested recently that a He-rich WD (a He WD or a hybrid HeCO WD) that merges with a CO WD may produce an SN Ia. This theory was based on the double-detonation model, in which the shock compression in the CO core caused by the surface explosion of the He-rich shell might lead to the explosion of the whole CO WD. However, so far, very few binary population synthesis (BPS) studies have been made on the merger scenario of a CO WD and a He-rich WD in the context of SNe Ia. Aims: We aim to systematically study the Galactic birthrates and delay-time distributions of SNe Ia based on the merger scenario of a CO WD and a He-rich WD. Methods: We performed a series of Monte Carlo BPS simulations to investigate the properties of SNe Ia from the merging of a CO WD and a He-rich WD based on the Hurley rapid binary evolution code. We also considered the influence of different metallicities on the final results. Results: From our simulations, we found that no more than 15% of all SNe Ia stem from the merger scenario of a CO WD and a He-rich WD, and their delay times range from 110 Myr to the Hubble time. This scenario mainly contributes to SN Ia explosions with intermediate and long delay times. The present work indicates that the merger scenario of a CO WD and a He-rich WD can roughly reproduce the birthrates of SN 1991bg-like events, and cover the range of their delay times. We also found that SN Ia birthrates from this scenario would be higher for the cases with low metallicities.

Herbivore species richness, composition and community structure mediate predator richness effects and top-down control of herbivore biomass.

PubMed

Wilby, Andrew; Orwin, Kate H

2013-08-01

Changes in predator species richness can have important consequences for ecosystem functioning at multiple trophic levels, but these effects are variable and depend on the ecological context in addition to the properties of predators themselves. Here, we report an experimental study to test how species identity, community attributes, and community structure at the herbivore level moderate the effects of predator richness on ecosystem functioning. Using mesocosms containing predatory insects and aphid prey, we independently manipulated species richness at both predator and herbivore trophic levels. Community structure was also manipulated by changing the distribution of herbivore species across two plant species. Predator species richness and herbivore species richness were found to negatively interact to influence predator biomass accumulation, an effect which is hypothesised to be due to the breakdown of functional complementarity among predators in species-rich herbivore assemblages. The strength of predator suppression of herbivore biomass decreased as herbivore species richness and distribution across host plants increased, and positive predator richness effects on herbivore biomass suppression were only observed in herbivore assemblages of relatively low productivity. In summary, the study shows that the species richness, productivity and host plant distribution of prey communities can all moderate the general influence of predators and the emergence of predator species richness effects on ecosystem functioning.

Science, Sex, and Pictures: Reflections on Van Fraassen's Use of Perspectival Representations

NASA Astrophysics Data System (ADS)

Okruhlik, Kathleen

2014-03-01

Bas van Fraassen's brand of empiricism, as articulated in his well-known constructive empiricism and his more recent empiricist structuralism, has been developed using the so-called semantic approach to scientific theories. This approach has allowed van Fraassen to espouse quite a robust form of non-realism about unobservable entities while avoiding some of the problems that contributed to the demise of logical empiricism. I shall argue, however, that in other respects van Fraassen replicates many of the serious shortcomings associated with the earlier tradition -- despite the fact that his choice of language sometimes obscures those similarities. Because van Fraassen's empiricist structuralism is much less well-known than his constructive empiricism, the rather lengthy first section of this paper provides an overview and initial assessment of that position. Subsequent sections deal with the ways in which van Fraassen's very sophisticated form of empiricism not only fails to address some of the most serious shortcomings of logical empiricism but actually reinforces them. The chief focus is on the failure to address issues that arise from the historical and social contexts within which science is pursued -- this despite a vocabulary rich in references to perspectivity, pragmatics, context, use, and aims.

Evolutionary Design of Convolutional Neural Networks for Human Activity Recognition in Sensor-Rich Environments.

PubMed

Baldominos, Alejandro; Saez, Yago; Isasi, Pedro

2018-04-23

Human activity recognition is a challenging problem for context-aware systems and applications. It is gaining interest due to the ubiquity of different sensor sources, wearable smart objects, ambient sensors, etc. This task is usually approached as a supervised machine learning problem, where a label is to be predicted given some input data, such as the signals retrieved from different sensors. For tackling the human activity recognition problem in sensor network environments, in this paper we propose the use of deep learning (convolutional neural networks) to perform activity recognition using the publicly available OPPORTUNITY dataset. Instead of manually choosing a suitable topology, we will let an evolutionary algorithm design the optimal topology in order to maximize the classification F1 score. After that, we will also explore the performance of committees of the models resulting from the evolutionary process. Results analysis indicates that the proposed model was able to perform activity recognition within a heterogeneous sensor network environment, achieving very high accuracies when tested with new sensor data. Based on all conducted experiments, the proposed neuroevolutionary system has proved to be able to systematically find a classification model which is capable of outperforming previous results reported in the state-of-the-art, showing that this approach is useful and improves upon previously manually-designed architectures.

Evolutionary Design of Convolutional Neural Networks for Human Activity Recognition in Sensor-Rich Environments

PubMed Central

2018-01-01

Human activity recognition is a challenging problem for context-aware systems and applications. It is gaining interest due to the ubiquity of different sensor sources, wearable smart objects, ambient sensors, etc. This task is usually approached as a supervised machine learning problem, where a label is to be predicted given some input data, such as the signals retrieved from different sensors. For tackling the human activity recognition problem in sensor network environments, in this paper we propose the use of deep learning (convolutional neural networks) to perform activity recognition using the publicly available OPPORTUNITY dataset. Instead of manually choosing a suitable topology, we will let an evolutionary algorithm design the optimal topology in order to maximize the classification F1 score. After that, we will also explore the performance of committees of the models resulting from the evolutionary process. Results analysis indicates that the proposed model was able to perform activity recognition within a heterogeneous sensor network environment, achieving very high accuracies when tested with new sensor data. Based on all conducted experiments, the proposed neuroevolutionary system has proved to be able to systematically find a classification model which is capable of outperforming previous results reported in the state-of-the-art, showing that this approach is useful and improves upon previously manually-designed architectures. PMID:29690587

Emotion Knowledge and Attentional Differences in Preschoolers Showing Context-Inappropriate Anger.

PubMed

Locke, Robin L; Lang, Nichole J

2016-08-01

Some children show anger inappropriate for the situation based on the predominant incentives, which is called context-inappropriate anger. Children need to attend to and interpret situational incentives for appropriate emotional responses. We examined associations of context-inappropriate anger with emotion recognition and attention problems in 43 preschoolers (42% male; M age = 55.1 months, SD = 4.1). Parents rated context-inappropriate anger across situations. Teachers rated attention problems using the Child Behavior Checklist-Teacher Report Form. Emotion recognition was ability to recognize emotional faces using the Emotion Matching Test. Anger perception bias was indicated by anger to non-anger situations using an adapted Affect Knowledge Test. 28% of children showed context-inappropriate anger, which correlated with lower emotion recognition (β = -.28) and higher attention problems (β = .36). Higher attention problems correlated with more anger perception bias (β = .32). This cross-sectional, correlational study provides preliminary findings that children with context-inappropriate anger showed more attention problems, which suggests that both "problems" tend to covary and associate with deficits or biases in emotion knowledge. © The Author(s) 2016.