bluuebunny/crossref_metadata_2025 huggingface dataset:
Elevation of CSF albumin in old sheep: relations to CSF turnover and albumin extraction at blood‐CSF barrier
Authors: Chen Ruo‐Li , Chen Carl Pai‐Chu , Preston Jane Elizabeth
Published: March 2010

J. Neurochem.(2010)113, 1230–1239.

Albumin is the most abundant protein in both CSF and plasma, and albumin quotient is often used to assess the functions of brain barriers especially that of the blood‐CSF barrier [i.e. the choroid plexus (CP) which also secretes CSF]. In this study, we took albumin as a model molecule to investigate ageing‐related alterations in the CSF‐CP system in sheep. We found significant ageing‐related increases in the weight of lateral CP [122.4 ± 14.0 mg in the young, 198.6 ± 35.4 mg in the middle aged, 286.1 ± 25.1 mg in the old (p < 0.05)], in the CSF albumin as well as the albumin quotient. Albumin protein spots in old CSF displayed wider on 2D western immunoblotting images, and had higher densities on images of 2D large gels stained with Pro‐Q Emerald 488 compared to the young samples, suggesting ageing‐related post‐translational modification in the albumin. CSF secretion was reduced with age: 0.148 ± 0.013 mL/min/g in the young, 0.092 ± 0.02 mL/min/g in the middle aged, 0.070 ± 0.013 mL/min/g in the old (p < 0.05). The125I‐BSA extraction was not different among the sheep groups, nor was altered by temperature reduction, monensin, nocodazole, anti‐transforming growth factor β receptor II antibody, as well as unlabelled albumins. In conclusion, elevation of albumin in old CSF is associated with reduced CSF secretion by the CP, which size increases with age.125I‐BSA extract, reflecting the extracellular space rather than the active albumin uptake in the CP, is not different between ages. These early changes in health ageing may result in the accumulation and modifications of CSF proteins leading to neurotoxicity.
Cytosolic protein interactions of the schizophrenia susceptibility gene dysbindin
Authors: Mead Carri‐Lyn R. , Kuzyk Michael A. , Moradian Annie , Wilson Gary M. , Holt Robert A. , Morin Gregg B.
Published: March 2010

J. Neurochem. (2010) 113, 1491–1503.

Using immunoprecipitation, mass spectrometry, and western blot analysis we investigated cytosolic protein interactions of the schizophrenia susceptibility gene dysbindin in mammalian cells. We identified novel interactions with members of the exocyst, dynactin and chaperonin containing T‐complex protein complexes, and we confirmed interactions reported previously with all members of the biogenesis of lysosome‐related organelles complex‐1 and the adaptor‐related protein complex 3. We report interactions between dysbindin and the exocyst and dynactin complex that confirm a link between two important schizophrenia susceptibility genes: dysbindin and disrupted‐in‐schizophrenia‐1. To expand upon this network of interacting proteins we also investigated protein interactions for members of the exocyst and dynactin complexes in mammalian cells. Our results are consistent with the notion that impairment of aspects of the synaptic vesicle life cycle may be a pathogenic mechanism in schizophrenia.
Controlling the Formation of Silver Nanoparticles on Silica by Photochemical Deposition and Other Means†
Authors: Vinci John Cody , Bilski Piotr , Kotek Richard , Chignell Colin
Published: March 2010

Silver nanoparticles (Ag‐NP) on silica were produced in aqueous solution by deposition of silver on colloidal silica in a small cuvette using radiation from a xenon‐mercury lamp. Ag‐NP were also synthesized on a much larger scale with low‐level, long‐term visible light irradiation for several months. In both cases, the nanoparticle production was monitored by the appearance of the surface plasmon resonance (SPR) band at around 410 nm. The growth of the nanoparticles was directly related to the time exposed to radiation, which could be tracked spectrophotometrically over time. We also investigated the possibilities of rapid nanoparticle production without the assistance of radiation though silver oxide by adding alkali hydroxide, which is a relatively unexplored approach for syntheses of Ag‐NP on silica. The SPR absorption of Ag‐NP was used as a tool in evaluating the size and shape of the resulting nanoparticles along with dynamic light scattering and transmission electron microscopy data. In order to better utilize and understand Ag‐NP, we present various ways to control their production through initial concentration adjustments, irradiation effects, gravitational fractionation, sonication and silver oxide formation.
HISTORY OF ALGEBRA
Authors: Carnahan Walter H.
Published: March 2010

The articles of this series are from scripts of broadcasts over radio station WBAA. This series is a part of the Purdue University School of the Air. There is one broadcast each week on some subject of mathematics. The first series had the general title Mathematics Is Where You Find It and ran for thirteen weeks. A second series of thirteen broadcasts has the title Mathematical History and the Men Who Made It. The articles as here given are in the exact words in which they were broadcast. They have been timed to be read in thirteen and a half to fourteen and a half minutes a the rate found most effective for understanding by the radio audience. Rebroadcasting of these talks in the original form or with adaptations is permitted. Write to the author for specific permission for their use.
Middle School Students' Understanding of Number Sense Related to Percent
Authors: Gay A. Susan , Aichele Douglas B.
Published: March 2010

This study examined middle school students' understanding of percent, focusing on number sense. Participants in the study were 106 seventh‐grade and 93 eighth‐grade students. Students were given a written test that included 21 multiple‐choice questions and an open‐ended item. Research interviews were conducted with 28 selected students. Students performed better interpreting a quantity expressed as a percent given a pictorial continuous region than when a pictorial discrete set of circles was given. Students had difficulty interpreting a quantity expressed as a percent of a number. The strategies used by students to make comparisons about percents represent a wide range of correct and incorrect approaches to the questions. In addition to the use of 50% and 100% as common reference points, students successfully applied fractional relationships, estimation and mental computation to make comparisons. A variety of inappropriate strategies which included computational procedures and numerical comparisons were also employed, some of which resulted in the correct multiple‐choice response.
The Nature of Student Thinking in Life Science Laboratories
Authors: Shepardson Daniel P.
Published: March 2010

The nature of student thinking in confirmation and open‐inquiry laboratory activities was compared. Student thinking in laboratory activities was contextualized by the laboratory activity structure and teacher and student interactions. Students in each laboratory treatment were observed throughout five life science laboratories, with the life science topic consistent across treatments. From a frequency perspective there appeared to be no difference in the student thinking processes exhibited across life science content. Based on the multiple regression analysis, however, the nature of student thinking differed across laboratory treatments. Student thinking processes exhibited in confirmation laboratories emphasized procedures and techniques, making sense of and doing the laboratory, whereas student thinking in open‐inquiry laboratories emphasized data analysis, making sense of the results. Student‐student interactions contributed more to student thinking in open‐inquiry laboratories, whereas teacher‐student interactions promoted student thinking in confirmation laboratories.
In‐Service Teacher Education Through an After‐School Hands‐On Science Program
Authors: Spickler Theodore R. , Hernandez‐Azarraga Laurie C. , Komorowski Mary Ellen
Published: March 2010

An after‐school hands‐on science program was offered for two years for the purpose of stimulating in‐service elementary schoolteachers to increase their use of a hands‐on approach to the teaching of science and mathematics. Parents were brought into the after‐school classes as active partners in the education of their children. Surveys of parents and teachers yielded judgments of high regard for the effectiveness of the program. This intervention appeared to be of limited value however in bringing unscientifically oriented elementary school teachers up to a high level of proficiency in the hands‐on approach to science teaching.
Fibonacci Numbers and an Area Puzzle: Connecting Geometry and Algebra in the Mathematics Classroom
Authors: Sullivan Mary M. , Panasuk Regina M.
Published: March 2010

A mathematical puzzle that asks about “missing” area leads to an exploration of the Fibonacci sequence as well as genuine inquiry in plane geometry connected to algebra. This article discusses the inquiry, the concepts, the solution, and an extension that deepens all students’ understanding of connections between algebra and geometry.
Student‐Invented Numeration Systems: Pattern‐Analysis and Mathematical Understanding
Authors: Senger Elizabeth S.
Published: March 2010

Thirteen fifth graders were given an assignment to invent their own numeration systems, following a unit on bases and a look at early events in the history of numbers. The task presented options that required the students to make decisions (such as whether to use a base, which base to use, design of symbols, etc.), and build a rationale for the elements of their system. Analyses of patterns embedded in their invented systems provided an assessment of student understanding of numeration. The progression of more and less complex thinking related to the student's choice of a base other than 10, consistency of logic throughout the system in words and symbols, rationale for change, and perception of real life examples that would change if the system was adopted. The invention task is presented as another way to make connections.
Lakatos’Proofs and Refutations Comes Alive in an Elementary Classroom
Authors: Atkins Sandra L.
Published: March 2010

This paper presents an alternative pedagogy implicit in Imre Lakatos’ Proofs and Refutations: The Logic of Mathematical Discovery. Through the voices of his characters, Lakatos reveals that learning mathematics is a discourse laden activity. In this approach it is acceptable, if not preferable, to refute a conjecture. Examples of the use of a Lakatosian approach in an elementary classroom are given. In this classroom setting students are able to propose more mature solutions, through posing and refuting conjectures.
Performance Assessment in Science as a Tool to Enhance the Picture of Student Learning
Authors: Shymansky James A. , Enger Sandra , Chidsey Jennifer L. , Yore Larry D. , Jorgensen Margaret , Henriques Laura , Wolfe Edward W.
Published: March 2010

The Iowa Assessment Project was funded by the National Science Foundation to explore the feasibility of combining the expertise of science teachers, science educators, and test developers to build innovative performance assessments that complement traditional, norm‐referenced, multiple‐choice science tests. The science teachers, graduate students, and science educators designed and tested performance assessment tasks to enhance the picture of science understanding in students through multiple points of evidence. This paper describes the design of four science performance tasks for Grade 9 students and the relationship between their performance on these tasks and multiple‐choice items in the Iowa Tests of Educational Development. Students and schools used to develop the tasks were not included in the verification sample.
Preparing Science Teachers in an Era of Reform: Practitioners' Perspectives of Methods Courses
Authors: Letts William J. , Bailey Bambi L. , Scantlebury Kathryn
Published: March 2010

With recent national calls for the reform of science education have come standards that delineate not only science content but also assessment, pedagogy, and teachers’ professional development. If teachers must teach science differently, then teacher preparation must change. This study asked 31 inservice secondary science teachers to complete a survey about topics for inclusion in a secondary science methods course. Respondents ranked a list of prespecified topics and had an opportunity to suggest other topics for inclusion in the course. Results showed that the majority of prespecified potential topics were judged important enough by these teachers to warrant inclusion in a methods course, though no individual added topic appeared on more than two surveys. Results demonstrate that these teachers believe teaching many of the traditional topics in science methods courses is still needed. In addition, they advocated the inclusion of several topics that either represent recent technological and theoretical advances, or longstanding ideas that have recently received considerable attention.
Integrating Tech Prep into Science Teacher Preparation
Authors: Gilbert Steven W.
Published: March 2010

Tech Prep is an emerging educational reform in the United States. Thirty of 37 states responding to a recent survey had some type offormal Tech Prep initiative in place (R. Hayes, 1995). Although Tech Prep has received its strongest backing from practitioners in technology education, science teacher educators must prepare teachers for these programs. The problem is that few may be ready. This paper provides an overview of Tech Prep and a model for its integration into the K‐12 curriculum. It then discusses implications for science and mathematics teacher preparation.
What Can Be Learned From Informal Student Writings in a Science Context?
Authors: Levine Tamar , Geldman‐Caspar Zehava
Published: March 2010

This exploratory study analyzed four informal science‐related writing tasks produced by 374 seventh‐grade students (172 boys and 202 girls) from two schools with different socioeconomic populations. The study demonstrates that students' informal writing in science contexts can provide a rich source of information regarding students' cognitive and attitudinal engagement with science. Students' writing reflects the level at which students understand previously learned science‐related ideas and gives insight into themes and issues they would be interested in learning. This study further demonstrates how students organize and personalize science knowledge acquired inside as well as outside of school when given novel and unconventional (informal) science‐related tasks. The study also demonstrates that informal writing tasks encourage students to express opinions, values, and attitudes associated with science and science learning. Examples are provided of similarities and differences in students' writing preferences and in the quality of writing produced by boys and girls. Suggestions for further studies for teachers and researchers are discussed.
Promoting Equity in Secondary Science and Mathematics Classrooms With Biography Projects
Authors: Daisey Peggy
Published: March 2010

Teachers have been called upon to give their students the opportunity to consider the perspectives of diverse individuals across the science and mathematics curriculum. This is because inclusion enhances motivation and achievement. Biographies provide context for construction of knowledge, vicarious experiences, positive attitudes toward instruction, and literacy enhancement. The purpose of this paper is to provide a rationale for including biography projects representing diverse contributors to science and mathematics, describe a biography project assignment used in a methods course for secondary teacher preparation, provide preservice teachers' comments about the assignment, and make connections to current research about equitable instruction.
Implicit Assumptions and Communication in Statistics
Authors: Pereira‐Mendoza Lionel , Schulz Henry
Published: March 2010

Statistics is becoming an increasingly important component of the school curriculum. The subject provides students with opportunities to explore situations that they read about or face in their everyday lives. This article describes a statistics project that focuses on communicating conclusions and on understanding implicit assumptions that may affect conclusions based on the information. The ability to make a table and draw graphs and charts is an important component of statistical education. However, the ability to communicate ideas to others and understand implicit assumptions associated with data are key objectives of educating students for a world that increasingly relies on statistical information as a means of mass communication.
A Telecommunications Project to Empower Kansas Elementary/Middle Level Teachers as Change Agents for Integrated Science and Mathematics Education
Authors: Slater Timothy F. , Coltharp Hazel , Scott Steven A.
Published: March 2010

Nineteen elementary and 5 middle school in‐service teachers served as regional lead teachers to provide 13 two‐ and four‐day workshops for 235 in‐service teachers. The lead teachers attended 100 hours of inservice training on national science/math reform curricula, cognitive theory, pedagogical strategies for enhancing problem solving, and authentic assessment procedures. The lead teachers then selected $30,000 worth of instructional materials for use in their classrooms. Subsequently, they developed four hands‐on‐manipulative‐based workshops through extensive use of video‐teleconferencing technology. The lead teachers strongly believe that this extensive project has made a permanent positive impact on the quality and quantity of integrated science and math instruction in Kansas.
Children's Perspectives on the Engagement Potential of Mathematical Problem Tasks
Authors: English Lyn D.
Published: March 2010

This article examines elementary students' perspectives on the engagement potential of particular mathematical problems and students' views on their general classroom problem activities. Third‐, fifth‐, and seventh‐grade children from different reform‐oriented classrooms were individually interviewed about (a) how they would improve their classroom problem‐solving activities and (b) the problems they find the most and least potentially engaging when presented with a range of routine and nonroutine problems. The children requested more relevant, meaningful, and interesting problem experiences in their classrooms, and the fifth and seventh graders requested more representational materials. The children's criteria for determining potentially engaging and nonengaging problems primarily pertained to problem structure and perceived cognitive demands. The nonroutine examples that focused on important reasoning processes and did not involve computation had the greatest engagement potential, while the computational problems had the least appeal.
Student Attitudes and Calculus Reform
Authors: Bookman Jack , Friedman Charles P.
Published: March 2010

This paper compares the attitudes about mathematics of students from traditionally taught calculus classes and those from a “reformed” calculus course. The paper is based on three studies, which together present a consistent picture of student attitudes about calculus reform. The reformed course appeared to violate students' deeply held beliefs about the nature of mathematics and how it should be learned. Although during their first months in the reformed course most students disliked it, their attitudes gradually changed. One and 2 years after, reform students felt significantly more than the traditionally taught students that they better understood how math was used and that they had been required to understand math rather than memorize formulas.
Geometric Knowledge of Middle School Students in a Reform‐based Mathematics Curriculum
Authors: Carroll William M.
Published: March 2010

National and international studies have found U.S. elementary students to be weak in their understandings and applications of geometric concepts. The University of Chicago School Mathematics Project's (UCMSP) Everyday Mathematics Program is one of the current reform‐based elementary curricula incorporating geometry throughout the K‐6 curriculum, with an emphasis on hands‐on and problem‐solving activities. In this study, the geometric knowledge of fifth and sixth graders using the UCSMP curriculum is compared to the knowledge of students using more traditional curricula. Because UCSMP students had been in the program since kindergarten, this research attempts to measure the longitudinal effects of such an approach. Along with an overall score, a subset of test items was used to assign each student a van Hiele level for geometric thinking, as well as a reasoning score. On all measures, UCSMP students substantially outperformed their counterparts, and nearly all differences were significant. Aspects of the UCSMP curriculum and the van Hiele model for learning geometry are discussed relative to these results.
Learning How Amanda, a High School Cerebral Palsy Student, Understands Angles
Authors: Shaw Kenneth L. , Baker Amanda , Durden Paul
Published: March 2010

Little is known about how well cerebral palsy students learn high school geometry. A case study was used to better understand how one student, Amanda, understood angles. Three major accommodations were made to assist her in learning: a) a self‐paced curriculum, b) The Geometer's Sketchpad, and c) nontraditional assessment (portfolio, interviews, observations). It was found that Amanda needed a lot of time to process visual information. The orientation of angles, the complexity of the diagram, and the length of the side of an angle all had an impact on her understanding. The software was beneficial for Amanda, because she could hide unnecessary and distracting information, she could make her drawings legible, and she could measure the angles without relying on her own visual perception.
Blended Science: The Rewards and Challenges of Integrating the Science Disciplines for Instruction
Authors: McComas William F. , Wang HsingChi A.
Published: March 2010

This paper provides an overview of blended science instruction, a term used to represent instructional plans by which the science disciplines are connected to each other and occasionally to other school subjects. The central rationales for such instruction, the historical development of blended instructional plans, and a review of the current proponents and forms of such instruction are provided. The primary varieties of blended instruction, including integrated, unified, and coordinated science, are compared and contrasted. Special attention is given to the major recommendations in support of blended science coming from philosophical, psychological, pedagogical, and pragmatic domains. The conclusions section includes some of the challenges facing those who plan an integrated teaching focus.
Potential Benefits and Barriers to Integration
Authors: Meier Sherry L. , Nicol Marsha , Cobbs Georgia
Published: March 2010

The rhetoric surrounding integration of mathematics and science abounds. Professional organizations’ standards and recommendations for reform in mathematics and science education each point out the need to make connections among various disciplines. However, some remain unconvinced, citing a lack of research supporting the assertion that integration improves student achievement. This article examines the current situation, discusses the growing body of related research, and examines the implementation issues related to integrated curriculum projects. The conclusion calls for mathematics and science educators to work collaboratively to address implementation issues surrounding reform of any kind and to explore further the possibilities of integration.
A Blueprint for Problem Posing
Authors: Gonzales Nancy A.
Published: March 2010

The purpose of this paper is to outline a plan of action designed to enhance growth in problem‐posing skills. The “blueprint” provides a model for teachers and teacher educators who wish to integrate more problem posing into their curriculum. Specific activities and instructional strategies are cited to illustrate the development of problem posing as a process in the classroom.
Teaching Length Measurement: Research Challenges
Authors: Clements Douglas H.
Published: March 2010

Many publications and curriculum materials promote a specific instructional sequence for introducing length measure: gross comparisons of length, measurement with nonstandard units such as paper clips, measurement with manipulative standard units, and finally measurement with standard instruments such as rulers. Several recent studies, however, imply that aspects of this traditional approach may not match children's developmental progression. This article describes several studies that challenge conventional wisdom regarding the teaching and learning of nonstandard and standard units, rulers, and measurement sense and draws educational implications from their results.
The Development and Validation of the Measure of Acceptance of the Theory of Evolution Instrument
Authors: Rutledge Michael L. , Warden Melissa A.
Published: March 2010

A biology teacher's acceptance or rejection of evolutionary theory as a scientifically valid explanation is potentially important to the role that evolution takes in the high school biology curriculum. Due to the nature of available instrumentation, our understanding of teacher acceptance of this complex overreaching biological theory may be incomplete or confounded. This paper describes the development and validation of the Measure of Acceptance of the Theory of Evolution (MATE)—a 20‐item Likert‐scaled instrument that assesses teachers' overall acceptance of evolutionary theory. Chronbach alpha reliability of the MATE is also reported.
Mathematical Dimensions of Students' Use of Proportional Reasoning In High School Physics
Authors: Akatugba Ayo Harriet , Wallace John
Published: March 2010

This study examines the mathematical processes used by students when solving physics tasks requiring proportional reasoning. The study investigates students' understanding and explanations of their mathematical processes. A qualitative and interpretive case study was conducted with 6 students from a coeducational urban high school for 5 months. Students were engaged with some high school physics tasks requiring proportional reasoning, during which a hermeneutic dialectic design was used to investigate their processes, understandings, and difficulties. Research techniques such as interviews, dialectical discourses, journal dialogue, and video and audio recordings were employed to generate, analyze, and interpret data. Results of the study indicate that the students employed mathematical proportional reasoning patterns and algorithms which they could not explain. Students also had difficulties translating physics tasks into mathematical statements, symbols, and relations. Students could not perform mathematical operations that were not directly obvious from the physics tasks, and some had difficulty with division. Students did not have adequate understanding of the mathematical processes involved in proportional reasoning.
The Border Crossings of a Multicultural Science Education Enthusiast
Authors: Luft Julie A.
Published: March 2010

Jill was a preservice science education student who wanted to make science more accessible to all students. This study is an examination of the “borders” she encountered as she completed her student teaching in a cultural setting that was different from her own. Her student teaching experience was documented through interviews, participant observations, field notes, lesson plans, and a journal. An inductive analysis of the documents and a context chart of the coded data revealed that Jill encountered the (a) cultural border of her students, (b) cultural border of science instruction, and (c) cultural border of the school. While some borders were crossed, others were not. This study suggests that during field experiences, preservice teachers may encounter multiple cultural borders, some consistent and some inconsistent with their instructional philosophy. As student teachers work with diverse populations, supervisors and cooperating teachers need to recognize the borders student teachers will encounter and encourage student teachers to examine their beliefs about practice as a means to acknowledge and understand the encountered borders.
A Literature Review of Science and Mathematics Integration
Authors: Czerniak Charlene M. , Weber William B. , Sandmann Alexa , Ahern John
Published: March 2010

Integrated curricula has gained a great deal of acceptance among educators. Many educators provide testimonials about the effectiveness of units they teach, and many professional organizations stress integration across the curriculum. However, few empirical studies exist to support the notion that an integrated curriculum is any better than a well‐designed traditional curriculum. Some educators question integration across the curriculum, because in the effort to integrate topics, science and mathematics content becomes superficial and trivial. This paper presents a review of the literature on integrated curricula. It concludes with a call to action for members of School Science and Mathematics Association.
Preservice Teacher Beliefs About Proofs
Authors: Mingus Tabitha T. Y. , Grassl Richard M.
Published: March 2010

This article describes a study of backgrounds, beliefs, and attitudes of teachers about proofs. Thirty preservice elementary teachers enrolled in a mathematics content course and 21 secondary mathematics teachers in an abstract algebra course were surveyed. The study explored four issues: preservice teachers' experiences/exposure to proof, their beliefs about what constitutes a proof and the role of proof in mathematics, and their beliefs about when proof should be introduced in grades K‐12. Results of the survey are described as a means for discussing the backgrounds and beliefs future teachers hold with regard to teaching proofs in their own classrooms. Finally, a short collection of sample explorations and questions, which could be used to encourage the thinking and writing of proofs in grades K‐12, is provided. One of these questions was posed to 215 secondary students; examples of their reasoning and a discussion of the various techniques employed by the students are included.
Integrating Science, Mathematics, and Technology in Middle School Technology‐Rich Environments: A Study of Implementation and Change
Authors: James Robert K. , Lamb Charles E. , Householder Daniel L. , Bailey Melynda A.
Published: March 2010

The GTECH project, funded through a grant from the GTE Foundation, prepared school teams of science, mathematics and technology teachers and an administrator to set goals for their local schools regarding implementation of electronic technology and integration of content across curricular areas. A variety of teacher‐centered staff development strategies were used to enable participants to achieve local school objectives, model and encourage active learning environments involving technology, develop integrated curriculum and provide training to their peers. GTECH staff provided workshops and summer institutes based on teacher feedback and classroom observations. Data from the Stages of Concerns Questionnaire assisted the staff in designing effective staff development activities. Over the 2‐year period, teacher teams developed and implemented integrated instructional materials and developed skills in using HyperStudio, PowerPoint, telecommunications applications, and instructional resources from the Internet. They also linked instruction to new state and national standards in science, mathematics, and technology. GTECH teachers reported that their students have expanded their knowledge and skill in problem solving, teamwork, technical expertise, and creativity.
A Case Study of the Effectiveness of Teacher Experience in the Use of Explanation‐Based Assessment in High School Physics
Authors: Lawrence Michael , Pallrand George
Published: March 2010

This article reports on the results of a study involving an innovative assessment program initiated to investigate student predictions and revised explanations regarding a variety of optical phenomena. The assessments were administered via videotape to two classes of high school physics students from different high schools. Two high school teachers with similar educational and teaching backgrounds administered the tapes to the two groups of students. The school environments and the ability levels of the two student groups were similar. The students of the teacher with greater experience with this new form of assessment provided considerably more substantive explanations to the phenomena presented on the videos. The results of the case study suggest that the introduction of new forms of assessment in science education, although desirable, will require significant reordering of the goals and strategies of science teaching.
Science Education for the 21st Century
Authors: Hurd Paul DeHart
Published: March 2010

Paul DeHart Hurd was a biology teacher and science supervisor in Colorado and California high schools and junior colleges for 20 years and a professor of science education at Stanford University for 22 years. He has authored 11 books and monographs on developments in the sciences and over 300 articles on various aspects of science education in the US and foreign countries. He has served on the National Science Foundation's Advisory Committee for Science Education and as a special educational consultant to the National Academy of Sciences, Commission on Life Sciences. Honors include the Apollo Award from the National Aeronautics and Space Agency, the Distinguished Contributions to Science Education Through Research Award from the National Association for Research in Science Teaching, and the Award for National Leadership in Science Education from the National Science Teachers Association. Dr. Hurd is currently focusing his writings on the history of science and technology education in the US over the past 200 years and current activities to modernize the precollege science curriculum.
Teaching for Understanding and Application of Science Knowledge
Authors: Gallagher James J.
Published: March 2010

James Gallagher is Professor of Science Education at Michigan State University and currently co‐editor of Journal of Research in Science Teaching. He was a member of the Working Group on Teaching in the formulation of National Science Education Standards. His recent work has included the me of continuous assessment as a tool to aid teachers in teaching for understanding.
The diffeotopy group of S1×S2 via contact topology
Authors: Ding Fan , Geiges Hansjörg
Published: March 2010

As shown by Gluck in 1962, the diffeotopy group of S1×S2 is isomorphic to ℤ2⊕ℤ2
⊕ℤ2. Here an alternative proof of this result is given, relying on contact topology. We then discuss two applications to contact topology: (i) it is shown that the fundamental group of the space of contact structures on S1×S2, based at the standard tight contact structure, is isomorphic to ℤ; (ii) inspired by previous work of Fraser, an example is given of an integer family of Legendrian knots in S1×S2#S1×S2 (with its standard tight contact structure) that can be distinguished with the help of contact surgery, but not by the classical invariants (topological knot type, Thurston–Bennequin invariant, and rotation number).
Lifting of characters on p-adic orthogonal and metaplectic groups
Authors: Howard Tatiana K.
Published: March 2010

Let F be a p-adic field. Consider a dual pair $({\rm SO}(2n+1)_+, \widetilde {{\rm Sp}}(2n)),$ where SO(2n+1)+ is the split orthogonal group and $\widetilde {{\rm Sp}}(2n)$ is the metaplectic cover of the symplectic group Sp(2n) over F. We study lifting of characters between orthogonal and metaplectic groups. We say that a representation of SO(2n+1)+ lifts to a representation of $\widetilde {{\rm Sp}}(2n)$ if their characters on corresponding conjugacy classes are equal up to a transfer factor. We study properties of this transfer factor, which is essentially the character of the difference of the two halves of the oscillator representation. We show that the lifting commutes with parabolic induction. These results were motivated by the paper ‘Lifting of characters on orthogonal and metaplectic groups’ by Adams who considered the case F=ℝ.
Tire Damping Effect on H2 Optimal Control of Half-Car Active Suspensions
Authors: Türkay Semiha , Akçay Hüseyin
Published: March 2010

In this note, the root-mean-square response of a half-car model following a random road profile is studied. Road excitation at the front wheel is modeled by a first-order linear shape filter driven by white-noise and the temporal correlation between the front and the rear wheels is predicted by a second-order Pade filter. It is demonstrated that the effect of tire damping on the rms response of actively controlled half-car suspension system can be significant, in particular, at high vehicle velocities.
Measured Dynamic Properties of Flexible Hoses
Authors: Johnston D. Nigel , Way Tim M. , Cone Kerry M.
Published: March 2010

A method for measuring the impedance matrix and the dynamic properties of a liquid-filled flexible hose is described in this paper. Dynamic hose properties are presented for a wide range of hose types. Nylon-reinforced hoses are shown to have considerably lower bulk moduli and stiffnesses than steel-reinforced hoses. The dynamic bulk moduli and stiffnesses are shown to be significantly and consistently higher than the static values. These results may be used to give an estimate of representative properties for a hose, based on its maximum pressure rating and its type of reinforcement.
PEM Based Sensitivity Analysis for Acoustic Radiation Problems of Random Responses
Authors: Liu Baoshan , Zhao Guozhong , Li Alex
Published: March 2010

A new effective method for computing the acoustic radiation and its sensitivity analysis of a structure subjected to stochastic excitation is presented. Previous work in the area of structural and acoustic sensitivity analysis systems was mostly focused on the deterministic excitation. New methods are developed to account for stochastic excitation. The structural-acoustic response is calculated using finite element method and boundary element method combined with stochastic analysis techniques. An accurate and highly efficient algorithm series for structural stationary random response analysis, pseudo-excitation method (PEM), is extended to acoustic random analysis in this paper, which was used to calculate structural random analysis in the past. So the acoustic radiation problems of random responses are transformed to the structural-acoustic harmonic analyses. This is a time-saving progress in comparison with traditional method. Based on the PEM, the acoustic radiation sensitivities of the structure are developed in emphasis that are transformed to harmonic sensitivity analyses. They are validated by comparing with the results of finite difference sensitivity method. Numerical examples are given to demonstrate the effectiveness of the methods and the program.
A Note on the Use of Approximate Solutions for the Bending Vibrations of Simply Supported Cracked Beams
Authors: Rubio L. , Fernández-Sáez J.
Published: March 2010

The main goal of this note is to discuss the applicability of approximate closed-form solutions to evaluate the natural frequencies for bending vibrations of simply supported Euler–Bernoulli cracked beams. From the well-known model, which considers the cracked beam as two beams connected by a rotational spring, different approximate solutions are revisited and compared with those found by a direct method, which has been chosen as reference.
Advanced Signal Processing Tools for the Vibratory Surveillance of Assembly Faults in Diesel Engine Cold Tests
Authors: Delvecchio Simone , D’Elia Gianluca , Mucchi Emiliano , Dalpiaz Giorgio
Published: March 2010

This paper addresses the use of several signal processing tools for monitoring and diagnosis of assembly faults in diesel engines through the cold test technology. One specific fault is considered here as an example: connecting rod with incorrectly tightened screws. First, the experimental apparatus concerning the vibration tests is introduced. Subsequently, the dynamic analysis of the engine has been carried out in order to calculate the connecting rod forces against the crankpin for predicting the position where mechanical impacts are expected. Then, a vibration signal model for this type of faults is introduced. It deals with the cyclostationary model in which the signal is subdivided into two main parts: deterministic and nondeterministic. Finally, the acceleration signals acquired from the engine block during a cold test cycle at the end of the assembly line are analyzed. For quality control purposes in order to obtain reliable thresholds for the pass/fail decision, a method based on the image correlation of symmetrized dot patterns is proposed. This method visualizes vibration signals in a diagrammatic representation in order to quickly detect the faulty engines in cold tests. Moreover, the fault identification is discussed on the basis of the cyclostationary model of the signals. The first-order cyclostationarity is exploited by the analysis of the time synchronous average (TSA). In addition, the residual signal is evaluated by subtracting the TSA from the raw synchronized signal, and thus, the second-order cyclostationarity analysis is developed by means of the Wigner–Ville distribution (WVD), Wigner–Ville spectrum (WVS), and mean instantaneous power. Moreover, continuous wavelet transform is presented and compared with the WVD and WVS.
Damage Detection in Nonlinear Systems Using Optimal Feedback Auxiliary Signals and System Augmentations
Authors: D’Souza Kiran , Epureanu Bogdan I.
Published: March 2010

An optimal sensitivity enhancing feedback control has been proposed recently. This method differs from previous sensitivity enhancing approaches because in addition to placing the closed-loop eigenvalues of the interrogated system, the eigenvectors are also optimally placed. This technique addresses two major limitations of frequency-based damage detection methods: the low sensitivity of the frequencies to damages and the limited range of damage scenarios identifiable from frequency-only measurement data. An unresolved challenge is enhancing sensitivity for nonlinear systems. This paper addresses this challenge by using optimal feedback auxiliary signals to enhance sensitivity for damage detection in nonlinear systems. The nonlinearity is accounted for by creating augmented linear models of higher order (in a higher dimensional state space). The methodology for constructing augmented linear systems with this property has been previously proposed by the authors (2008, “Multiple Augmentations of Nonlinear Systems and Generalized Minimum Rank Perturbations for Damage Detection,” J. Sound Vib., 316(1-5), pp. 101–121). Herein, the focus is on generalizing the previous work on sensitivity enhancing feedback and on system augmentation for enhancing sensitivity of damage detection in nonlinear systems. Results obtained by applying the optimal feedback auxiliary signals and optimal augmentation to a nonlinear mass-spring system are presented.
Modal Methodology for the Simulation and Optimization of the Free-Layer Damping Treatment of a Car Body
Authors: Danti Marco , Vigè Davide , Nierop Guido Vincent
Published: March 2010

The cost and weight reduction requirements in automotive applications are very important targets in the design of a new car. For this reason, all the components of the vehicle have to be optimized and the design of the damping material layout has to be deeply analyzed in order to have a good noise, vibration, and harshness (NVH) performance with minimum mass and cost. A tool for the optimization of the damping material layout has been implemented and tested; the need to explore the entire design space with a big number of variables suggested the use of a genetic multi-objective algorithm for the optimization. These algorithms require a large number of calculations and the solution of the complete NVH model would be too expensive in terms of computation time. For this reason, a new software tool has been developed based on the simulation of the damping material treatments by means of an auxiliary mass and stiffness matrix, which was added to the baseline modal base; using this procedure, the required time for the simulation of each damping material layout configuration is reduced to a few minutes, allowing to exploit the genetic algorithm capability to efficiently explore the design space. As a result, some configurations with an important mass reduction or a much better acoustic performance have been found. This method has been verified on a simple Aluminum box in order to verify all the assumptions and to test the effectiveness in predicting the vibration levels of plates with free layer damping added to it.
Performance of a Novel Rotating Gas-Liquid Separator
Authors: Willems G. P. , Kroes J. P. , Golombok M. , van Esch B. P. M. , van Kemenade H. P. , Brouwers J. J. H.
Published: March 2010

A novel gas separation process makes use of a rotating phase separator to separate micron-sized droplets from a gas stream. Based on an industrial scale design, a water/air separator is constructed and tested. The first experiment concerns the drainage of large fractions of separated liquid. During operation, drainage is observed via windows and a descriptive model is formulated. Because of the major influence on overall separation efficiency, liquid drainage is a key issue in the separator design. The second experiment comprises a droplet collection efficiency measurement using micron-sized droplets dispersed within the airstream. The separation efficiency of fine droplet removal is measured. This is an important factor in reducing capital costs.
Reliable and Accurate Prediction of Three-Dimensional Separation in Asymmetric Diffusers Using Large-Eddy Simulation
Authors: Schneider Hayder , von Terzi Dominic , Bauer Hans-Jörg , Rodi Wolfgang
Published: March 2010

Large-eddy simulations (LES) and Reynolds-averaged Navier–Stokes (RANS) calculations of the flow in two asymmetric three-dimensional diffusers were performed. The setup was chosen to match an existing experiment with separation. Both diffusers possess the same expansion ratio but differ in performance. The aim of the present study is to find the least expensive method to reliably and with reasonable accuracy account for the impact of the change in geometry. RANS calculations failed to predict both the extent and location of the separation. In contrast, LES with wall-functions delivered results within the accuracy of the experimental data.
A Novel 2D Incompressible Viscous Inverse Design Method for Internal Flows Using Flexible String Algorithm
Authors: Nili-Ahmadabadi Mahdi , Hajilouy-Benisi Ali , Ghadak Farhad , Durali Mohammad
Published: March 2010

In this investigation, the flexible string algorithm (FSA), used before for inverse design of subsonic and supersonic ducts in compressible flows with and without normal shock, is developed and applied for inverse design of 2D incompressible viscous internal flow with and without separation. In the proposed method, the duct wall shape is changed under an algorithm based on deformation of a virtual flexible string in flow. At each modification step, the difference between current and target wall pressure distributions is applied to the string. The method is an iterative inverse design method and utilizes the analysis code for the flow field solution as a black-box. Some validation test cases and design examples are presented here, which show the robustness and flexibility of the method in handling complex geometries. In cases with separated flow pressure distribution, a unique solution for inverse design problem does not exist. The design algorithm is a physical and quick converging approach and can efficiently utilize commercial flow analysis software.