bluuebunny/crossref_metadata_2025 huggingface dataset:
Long range surface polaritons supported by lossy thin films
Authors: Arnold Christophe , Zhang Yichen , Rivas Jaime Gómez
Published: March 2010

We demonstrate experimentally that strongly absorbing chalcogenide thin films can support long range surface polaritons. Moreover, the possibility to change the phase of this material allows us to investigate the influence of the permittivity of the thin film on the surface modes. We demonstrate the relative insensitivity of these modes to the permittivity of the thin film. Extending the range of materials that support long range surface polaritons to strongly absorbing layers opens new possibilities for applications that were thought to be limited to weakly absorbing media.
In-plane reorientation of magnetization in epitaxial exchange biased Fe/MnPd bilayers
Authors: Zhan Qing-feng , Krishnan Kannan M.
Published: March 2010

We investigated the in-plane reorientation of magnetization in epitaxial Fe/MnPd bilayers. The samples with various thicknesses of MnPd and Fe layers present a conventional square and an unusual two-step exchange biased hysteresis loops at different temperature. The shape of the loops is reproduced using the coherent rotation model and including the relative orientation of the uniaxial anisotropy with respect to the exchange bias. The parallel and perpendicular uniaxial anisotropies in the ferromagnetic layer are linked to the aligned and the reoriented states, respectively. The magnetic reorientation between the aligned and the reoriented states, which is determined by the competition between the interface exchange coupling and the intrinsic uniaxial energies, is shown to be driven by the temperature, as well as the thickness of MnPd and Fe layers.
Functionally distinct hematopoietic stem cells modulate hematopoietic lineage potential during aging by a mechanism of clonal expansion
Authors: Beerman Isabel , Bhattacharya Deepta , Zandi Sasan , Sigvardsson Mikael , Weissman Irving L. , Bryder David , Rossi Derrick J.
Published: March 2010

Aging of the hematopoietic stem cell compartment is believed to contribute to the onset of a variety of age-dependent blood cell pathophysiologies. Mechanistic drivers of hematopoietic stem cell (HSC) aging include DNA damage accumulation and induction of tumor suppressor pathways that combine to reduce the regenerative capacity of aged HSCs. Such mechanisms do not however account for the change in lymphoid and myeloid lineage potential characteristic of HSC aging, which is believed to be central to the decline of immune competence and predisposition to myelogenous diseases in the elderly. Here we have prospectively isolated functionally distinct HSC clonal subtypes, based on cell surface phenotype, bearing intrinsically different capacities to differentiate toward lymphoid and myeloid effector cells mediated by quantitative differences in lineage priming. Finally, we present data supporting a model in which clonal expansion of a class of intrinsically myeloid-biased HSCs with robust self-renewal potential is a central component of hematopoietic aging.
Going from where to why—interpretable prediction of protein subcellular localization
Authors: Briesemeister Sebastian , Rahnenführer Jörg , Kohlbacher Oliver
Published: March 2010

Motivation: Protein subcellular localization is pivotal in understanding a protein's function. Computational prediction of subcellular localization has become a viable alternative to experimental approaches. While current machine learning-based methods yield good prediction accuracy, most of them suffer from two key problems: lack of interpretability and dealing with multiple locations.

Results: We present YLoc, a novel method for predicting protein subcellular localization that addresses these issues. Due to its simple architecture, YLoc can identify the relevant features of a protein sequence contributing to its subcellular localization, e.g. localization signals or motifs relevant to protein sorting. We present several example applications where YLoc identifies the sequence features responsible for protein localization, and thus reveals not only to which location a protein is transported to, but also why it is transported there. YLoc also provides a confidence estimate for the prediction. Thus, the user can decide what level of error is acceptable for a prediction. Due to a probabilistic approach and the use of several thousands of dual-targeted proteins, YLoc is able to predict multiple locations per protein. YLoc was benchmarked using several independent datasets for protein subcellular localization and performs on par with other state-of-the-art predictors. Disregarding low-confidence predictions, YLoc can achieve prediction accuracies of over 90%. Moreover, we show that YLoc is able to reliably predict multiple locations and outperforms the best predictors in this area.

Availability:  www.multiloc.org/YLoc

Contact:  briese@informatik.uni-tuebingen.de

Supplementary information:  Supplementary data are available at Bioinformatics online.
Carers and the Issues They Face
Authors: Cameron Judith
Published: March 2010

With a rapidly ageing population, it is widely accepted that many more of us will become carers of a family member before needing care ourselves later in life. With anticipated medical advances and higher expectations with regard to quality of life, it is estimated that one in three of us will become a carer at some point. This article aims to define who carers are and their importance to the well-being of the general population, describe their health-related problems and explore the different ways GP surgeries can support them.
Personality Disorders
Authors: Amiel Cressida
Published: March 2010

The term ‘personality’ refers to the enduring characteristics which influence the way a person thinks, feels or behaves in a wide variety of circumstances. A personality is deemed to be ‘disordered’ when it causes suffering to that person or to other people. The Department of Health estimates that 10–13% of the adult population have personality disorders, and it is therefore extremely important that GPs are aware of current thinking regarding the classification, diagnosis and treatment of these complex conditions.
Single Oral Dose of Azithromycin Versus 5 Days of Oral Erythromycin or No Antibiotic in Treatment of Campylobacter Enterocolitis in Children: A Prospective Randomized Assessor‐Blind Study
Authors: Vukelic Dalibor , Trkulja Vladimir , Salkovic‐Petrisic Melita
Published: March 2010

Objective:

To evaluate efficacy of a single oral azithromycin dose versus standard oral erythromycin regimen or no antibiotic for Campylobacter enterocolitis in children younger than or equal to 12 years of age.

Patients and Methods:

Randomized parallel group assessor‐blind trial testing for inequality in efficacy between treatments was done. Patients (N = 120) were enrolled at less than or equal to 48 hours since disease onset to receive erythromycin 50 mg kg−1 day−1 for 5 days, single‐dose azithromycin 20 mg/kg or 30 mg/kg, or no antibiotic (no treatment control) (1: 1: 1: 1). Antibiotics were commenced 8 to 10 hours after enrollment. Patients were assessed at 24‐hour intervals for 6 days.

Results:

In the intent‐to‐treat analysis, Campylobacter eradication was achieved in 20 of 30 controls and in all of the patients treated with antibiotic. Incidence of clinical cure during the observed period was 15 of 30 in the control, 14 of 30 in the erythromycin, 20 of 30 in the lower, and 25 of 30 in the higher azithromycin dose group. With adjustment for age, sex, baseline disease severity, and disease duration before enrollment, only azithromycin 30 mg/kg was superior to no treatment: incidence ratio (IR) 1.76 (95% confidence interval [CI] 1.11–2.87). It was also superior to erythromycin (IR 1.80, 97.5% CI 1.13–2.84). Regarding time to clinical cure, only azithromycin 30 mg/kg was superior to no treatment (adjusted hazard ratio [HR] 4.90, 95% CI 2.44–9.84). It was also superior to erythromycin (HR 4.17, 97.5% CI 1.91–9.09). All treatments were well tolerated.

Conclusions:

The administration of single oral dose of azithromycin 30 mg/kg early after disease onset effectively eradicates the pathogen and accelerates clinical cure in childhood Campylobacter enterocolitis. It is clinically superior to an early commenced 5‐day erythromycin regimen, which apparently conveys no clinically relevant benefit over no antibiotic treatment.
A Qualitative Study of the Quality of Life of Children Receiving Intravenous Nutrition at Home
Authors: Emedo Marylyn‐Jane , Godfrey Emma I , Hill Susan M
Published: March 2010

Objectives:

To discover the views of children with severe intestinal failure treated with intravenous nutrition from early life and who remained heavily dependent on treatment throughout childhood.

Methods:

Seven children ages 7 to 17 years (mean 13 years) were interviewed. The diagnoses were enteropathy in 3, extreme short gut in 1, complex (associated mucosal inflammation and dysmotitlity) in 2, and intestinal pseudo‐obstruction in 1. They were treated with intravenous nutrition overnight at home that was administered by trained parents using the simplest possible system. The children were individually questioned about their lifestyle and health. Transcripts were analysed using interpretive phenomenological analysis.

Results:

Children coped well with life with intravenous nutrition (apart from septicaemia in 2 cases), but were troubled when complications of the underlying disease persisted (eg, nocturnal disturbance, stool frequency, abdominal pain). Children were aware that life was restricted (eg, fewer sleepovers with friends, fewer late nights out). There was a high level of family functioning. Older children wished to take care of themselves. The burdens of life with intravenous nutrition appear to be less significant for these children than living with the effects of chronic illness. There was resilience and acceptance in the face of illness‐related demands.

Conclusions:

This study has found that despite the problems they may face, it is possible for children fed intravenously at home to develop a level of resilience, maintain a positive outlook, and cope well with illness‐related demands even when they have had virtually lifelong severe intestinal failure. Families can continue to function well.
Oral Beclomethasone Dipropionate in Pediatric Active Ulcerative Colitis: A Comparison Trial With Mesalazine
Authors: Romano Claudio , Famiani Annalisa , Comito Donatella , Rossi Paolo , Raffa Vanessa , Fries Walter
Published: March 2010

Objective:

The objective of the study was to evaluate the clinical efficacy of oral beclomethasone diproprionate (BDP) in inducing clinical and endoscopic remission in children with mild to moderate active ulcerative colitis (UC).

Patients and Methods:

Thirty patients with active UC (pancolitis or left‐sided colitis) were enrolled in an open‐labeled, randomized, head‐to‐head study. Group 1 (n = 15) received oral BDP (5 mg/day) for 8 weeks, followed by maintenance therapy with oral mesalazine, 5‐aminosalycilate (5‐ASA); group 2 (n = 15) received oral 5‐ASA (80 mg · kg−1 · day−1). Assessments were carried out (at 4, 8, and 12 weeks) for clinical scores and for endoscopy (at 12 weeks), together with a final clinical assessment after 1 year follow‐up.

Results:

Patients treated with BDP showed a significant reduced clinical activity within 4 weeks (P < 0.001 vs pretreatment values) with 80% achieving clinical remission compared with 33% treated with only 5‐ASA (P < 0.025). A significant reduction in clinical activity was achieved by 5‐ASA after 8 weeks. Comparing clinical activity between BDP and 5‐ASA, the former did significantly better at 8 (P < 0.003) and at 12 weeks (P < 0.015). In 73% of BDP‐treated patients colonoscopy showed remission compared with 27% of 5‐ASA (P < 0.025). Both treatments led to better scores compared with pretreatment values (P < 0.001, both). Erythrocyte sedimentation rate was significantly reduced (P < 0.025 or less) with both treatments, whereas C‐reactive protein dropped significantly (P < 0.02) only in BDP.

Conclusions:

Oral BDP was well tolerated and acts significantly faster and more effectively than 5‐ASA in inducing clinical remission and endoscopic improvement in pediatric mild‐to‐moderate UC.
Congenital Diarrheal Disorders: Improved Understanding of Gene Defects Is Leading to Advances in Intestinal Physiology and Clinical Management
Authors: Berni Canani Roberto , Terrin Gianluca , Cardillo Giuseppe , Tomaiuolo Rossella , Castaldo Giuseppe
Published: March 2010

Congenital diarrheal disorders (CDD, Online Mendelian Inheritance in Man [OMIM] 251850) represent one of the most challenging clinical conditions for pediatric gastroenterologists because of the severity of the clinical picture and the broad range of disorders in its differential diagnosis. The number of conditions included within CDD has gradually increased. Recent advances made in the pathophysiology of these conditions have led to a better understanding of the more common diarrheal diseases. Based on the body of data accumulated in recent years, we suggest that CDD be classified in 4 categories depending on the alteration in absorption and transport of nutrients and electrolytes, enterocyte differentiation and polarization, enteroendocrine cell differentiation, and modulation of the intestinal immune response. Our knowledge of the genes responsible for CDD is also rapidly increasing, thanks to linkage studies based on genome‐wide analysis of polymorphisms. In this context, the identification of disease genes is a step forward in the diagnostic approach to a patient in whom CDD is strongly suspected. However, it is conceivable that faster, less expensive molecular procedures will, in the near future, become available. This approach could spare the patient invasive procedures and limit complications associated with a delay in diagnosis. Furthermore, carrier and prenatal molecular diagnosis may help pediatricians better manage the condition in the early stages of life.
Aspergillus niger: an unusual cause of invasive pulmonary aspergillosis
Authors: Person A. K. , Chudgar S. M. , Norton B. L. , Tong B. C. , Stout J. E.
Published: March 2010

Infections due to Aspergillus species cause significant morbidity and mortality. Most are attributed to Aspergillus fumigatus, followed by Aspergillus flavus and Aspergillus terreus. Aspergillus niger is a mould that is rarely reported as a cause of pneumonia. A 72-year-old female with chronic obstructive pulmonary disease and temporal arteritis being treated with steroids long term presented with haemoptysis and pleuritic chest pain. Chest radiography revealed areas of heterogeneous consolidation with cavitation in the right upper lobe of the lung. Induced bacterial sputum cultures, and acid-fast smears and cultures were negative. Fungal sputum cultures grew A. niger. The patient clinically improved on a combination therapy of empiric antibacterials and voriconazole, followed by voriconazole monotherapy. After 4 weeks of voriconazole therapy, however, repeat chest computed tomography scanning showed a significant progression of the infection and near-complete necrosis of the right upper lobe of the lung. Serum voriconazole levels were low–normal (1.0 μg ml−1, normal range for the assay 0.5–6.0 μg ml−1). A. niger was again recovered from bronchoalveolar lavage specimens. A right upper lobectomy was performed, and lung tissue cultures grew A. niger. Furthermore, the lung histopathology showed acute and organizing pneumonia, fungal hyphae and oxalate crystallosis, confirming the diagnosis of invasive A. niger infection. A. niger, unlike A. fumigatus and A. flavus, is less commonly considered a cause of invasive aspergillosis (IA). The finding of calcium oxalate crystals in histopathology specimens is classic for A. niger infection and can be helpful in making a diagnosis even in the absence of conidia. Therapeutic drug monitoring may be useful in optimizing the treatment of IA given the wide variations in the oral bioavailability of voriconazole.
RESEARCH TN BIOLOGY“XENIA”1
Authors: Waller A. E.
Published: March 2010

It is the object of this department to present to teachers of physics the results of recent research. In so far as is possible, the articles and items will be nontechnical, and it is hoped that they will furnish material that will be of value in the classroom. Suggestions and contributions should be sent to Dr. Homer C. Sampson, Department of Zoology, Ohio State University, Columbus, Ohio.
RESEARCH IN CHEMISTRY
Authors: Hopkins B. S.
Published: March 2010

It will be the object of this department to present each month the very latest results of investigations in the pedagogy of chemistry, to bring to the teacher those new and progressive ideas which will enable him to keep abreast of the times. Suggestions and contributions should be sent to Dr. B. S. Hopkins, University of Illinois. Urbana, III.
ORIGIN OF THE NAMES ARITHMETICAL AND GEOMETRICAL PROGRESSION AND PROPORTION
Authors: Cojori Florian
Published: March 2010

“You shall also understande, that there are infinite kindes of Progressions, but for you (as yet) two are sufficient to be exercised in, of whiche the one I call Arithmeticall, and the other Geometricall.” Robert Recorde, about 1543.
ILLINOIS COAL AND THE NEW ILLINOIS WATERWAY1
Authors: Utzig Esther W.
Published: March 2010

An investigation of conditions that will affect the transportation of coal on the proposed new Inland Waterway, with special attention to the Chicago Switching District, the chief consumer of Illinois coal.
SCIENCE QUESTIONS: April, 1935
Authors: Jones Franklin T.
Published: March 2010

Please send copies of Tests and Examinations to Franklin T. Jones, 10109 Wilbur Avenue, Cleveland, Ohio.

Send your most interesting question in Biology, Chemistry, General Science, or Physics, Join the GQRA (Guild Question Raisers & Answers). Have your class answer or propose a problem or question.

Please, check Mr. Reade's answer and Mr. Hoilman's comments with the solution Mr. Hebl gives to his own problem.
PROBLEM DEPARTMENT
Authors: Jamison G. H.
Published: March 2010

This department aims to provide problems of varying degrees of difficulty which will interest anyone engaged in the study of mathematics.

All readers are invited to propose problems and to solve problems here proposed. Drawings to illustrate the problems should be well done in India ink. Problems and solutions will be credited to their authors. Each solution, or proposed problem, sent to the Editor should have the author's name introducing the problem or solution as on the following pages.

The Editor of the department desires to serve its readers by making it interesting and helpful to them. Address suggestions and problems to G. H. Jamison, State Teachers College, Kirksville, Missouri.
BOOK REVIEWS
Authors: Parker Druley
Published: March 2010

Book reviewed in this article:

A Course of Study in Chemical Principles: by Arthur A. Noyes, Late Professor of Chemistry, California Institute of Technology and Miles S. Sherrill, Professor of Physical Chemistry, Massachusetts Institute of Technology. Second edition, rewritten

Chemistry and You: by B. S. Hopkins, Professor of Inorganic Chemistry, The University of Illinois; R. E. Davis, Head of the Chemistry Department, Lane Technical High School, Chicago; H. R. Smith, Head of the Chemistry Department, Lake View High School, Chicago; Martin V. McGill, Head of the Chemistry Department, Lorain High School, Lorain, Ohio; G. M. Bradbury, Head of the Science Department, Montclair High School, Montclair, New Jersey

Health and Achievement. A Textbook of Health with a Physiological Background: by Edgar A. Cockefair, Professor of Biology, Central Missouri State Teachers College and Ada Milarn Cockefair, Instructor in Physiology, West High School, Madison, Wis.

Methods and Materials for Teaching Biological Sciences. A Text and Source Book for Teachers in Training and in Service: by David F. Miller, Associate Professor of Zoology and Supervisor of Teacher Training in the Biological Sciences, Ohio State University and Glenn W. Blaydes, Associate Professor of Botany, Ohio State University

Adventures with Living Things. A General Biology: by Elsbeth Kroeber, Chairman Department of Biology James Madison High School, New York City and Walter H. Wolff, Chairman Department of Biology and General Science De Witt Clinton High School, New York City and Instructor, School of Education College of the City of New York

The Relative Merits of Three Methods of Subtraction: by John Theodore Johnson

Teaching Arithmetic in the Elementary School: by Robert Lee Morton

Elliptic and Hyperelliptic Integrals and Allied Theory: by the Late W. R. Westropp Roberts

Introduction to the Theory of Equations: by Louis Weisner

Analytic Geometry and Calculus: by Frederick S. Woods and Frederick H. Bailey

Mathematical Adventures: by Fletcher Durell

Trigonometry with tables: by Howard K. Hughes, Assistant Professor of Mathematics, Purdue University, and Glen T. Miller, Instructor in Mathematics, Purdue University

College Algebra: by Louis J. Rouse

Physical Geography and Geology: by L. Dudley Stamp

Science in General Education, A Report of the Committee on the Function of Science in General Education, Commission of Secondary School Curriculum, Progressive Education Association. V. T. Thayer, Chairman

Science Problems for the Junior High School: by Wilbur Beauchamp, John C. Mayfield, and Joe Young West

An Introduction to Laboratory Technique: by A. J. Ansley

Physics, A Textbook for Colleges: by Oscar M. Stewart
Software Reviews
Authors: McGrath Diane
Published: March 2010

Talking Dinosaurs

Adventure with Charts and Graphs: PROJECT ZOO
Software Review
Authors: McGrath Diane
Published: March 2010

The Newtonian Sandbox
BOOK REVIEWS
Authors: Abdi S. Wali
Published: March 2010

Book reviewed in this article:

Educational Prospective for Science Technology and Society in Japan, Japan Society for Science Education

All Natural Pogo, Norman F. Hale
A Look at Project AIMS
Authors: Deal Debby
Published: March 2010

Project AIMS (Activities that Integrate Mathematics and Science) began in 1981 as a National Science Foundation grant. Twelve years later it is a flourishing program which relies on materials developed and written by teachers, and one which uses inexpensive, easily acquired equipment and materials. It is particularly noteworthy that the focus of AIMS‐integration through hands‐on mathematics and science‐supports such recent initiatives as the NCTM Standards and Project 2061 of the AAAS, even though it predates both of them.
Development and Implementation of an Integrated Mathematics/Science Preservice Elementary Methods Course
Authors: Lonning Robert A. , DeFranco Thomas C.
Published: March 2010

If integration of mathematics and science is to occur, teacher preparation programs at colleges and universities must provide leadership in developing and modeling methods of teaching integrated content. This paper describes the development and implementation of an integrated mathematics/science preservice elementary methods course at the University of Connecticut. In planning the course several questions were addressed: (a) What does integration of mathematics and science mean? (b) What content should be taught in an integrated mathematics/science (IM/S) elementary methods course? and (c) How should an IM/S elementary methods course be taught? An important element of the course involved enlisting an exemplary elementary teacher who was released from her classroom one day per week to co‐teach the methods class. Establishing a definition of integration proved to be one of the most challenging aspects of course development. The authors determined that most difficulties in integration of disciplines result from attempts to “force” the integration. As the team struggled with the philosophical, theoretical and logistical problems in the development of the course, it became apparent why integration has not been more widely implemented. It is believed this model can be adapted to allow for integration of all content areas. Plans are currently underway to incorporate social studies into the methods class for Fall of 1993.
The Integration of Science and Mathematics Education: Highlights from the NSF/SSMA Wingspread Conference Plenary Papers
Authors: Berlin Donna F.
Published: March 2010

In April, 1991 the NSF/SSMA conference entitled “A Network for Integrated Science and Mathematics Teaching and Learning” was held at the Wingspread conference facility in Racine, Wisconsin. Five plenary papers were presented offering very diverse perspectives related to the integration of science and mathematics education. This publication summarizes the significant points advanced in each plenary paper. The full text of these papers is being published as part of the SSMA Monograph Series.
Science and Mathematics Equity Issues at a Local School District Level
Authors: Shroyer M. Gail , Borchers Carol A. , Smith Nancy J. , Wright Emmett L.
Published: March 2010

Many reports to the nation have revealed differences in the educational experiences of males and females. This is especially true in mathematics and science where females are not receiving the necessary educational background to develop the skills and understanding required to be citizens and employees in today's technological world. As a result, females are underrepresented in science, mathematics, and engineering professions. This study compares one school district's data with the data in national reports and then attempts to analyze what factors exist in the community and school district that reinforce and perpetuate inequitable situations for females. This study also provides a model for other school districts to conduct a self‐study of gender equity education issues.
BOOK REVIEWS
Authors: Abdi S. Wali
Published: March 2010

Book reviewed in this article:

Minerals of the World, Walter Schumann.

A‐Z of Snake Keeping, Chris Mattison.
Solving Equations and the Inverse of Mathematical Operations
Authors: Eberhart James G.
Published: March 2010

Many of the simpler equation‐solving problems in science and mathematics can be approached in a nontraditional way that de‐emphasizes skills with algebra and calculus. This alternative procedure emphasizes an examination of the steps or operations necessary to perform a calculation, followed by the inversion of those steps. Specifically, each step is replaced by its inverse, and the steps are performed in reverse order. The approach is especially attractive to students with limited mathematical skills.
Exploring Repunits
Authors: Toumasis Charalampos
Published: March 2010

This article describes a discovery activity which is organized and developed at two different levels of treatment corresponding to the different degree of mathematical maturity of students. Using an 8‐digit calculator, students at the first level (7‐9th graders) explore patterns which lead them to discover the properties of repunits and their relationships to many mathematical curiosities. At the second level (10‐12th graders) students may be interested in further extension exploring why these patterns emerge and offering algebraic justification.
Charting Northern Skies With the Aid of a Spreadsheet
Authors: Lucas Keith B.
Published: March 2010

An obstacle often encountered in preparing for an astronomical viewing evening is the difficulty of locating appropriate and easy‐to‐use star charts. This article describes, briefly, two types of star charts commonly available. Both are less than ideal for use by school students because of their complexity or lack of direct applicability to the observer's location. A strategy is outlined by which teachers can have students prepare, using a computer spreadsheet, their own easy‐to‐use star charts which are appropriate for the location, date, and time of viewing.
A Comparison of Sentential Logic Skills: Are Teachers Sufficiently Prepared to Teach Logic?
Authors: Easterday Kenneth E. , Galloway Linda L.
Published: March 2010

A sentential logic test consisting of 30 items was administered to advanced 7th grade, 8th grade, and 12th grade students and preservice secondary mathematics teachers in 1986 and 1992. The resulting data were compared with data obtained in a similar study conducted in 1976. An examination of the changes in scores by age level according to item type and semantic form was made over the three data collection periods. The results indicate that the impact of maturation and/or education has decreased in its effect on the development of logic skills. Concern is raised over preservice teachers' level of understanding of sentential logic.
Problem Solving: Teachers' Perceptions, Content Area Models, and Interdisciplinary Connections
Authors: Meier Sherry L. , Hovde Robert L. , Meier Ronald L.
Published: March 2010

Features of common problem‐solving models in mathematics and science, as well as those found in business and industry today, are discussed. Commonalties in the models are used to advance a case for interdisciplinary or integrated instruction in mathematics, science and technology. The Integrated Mathematics, Science and Technology (IMaST) program's problem‐solving model is presented as an example of a curriculum project that draws upon the commonalties in the problem‐solving models as a basis for a seventh grade integrated curriculum.
Numerical and Experimental Study of Interface Delamination in Flip Chip BGA Package
Authors: Guojun Hu , Tay Andrew A. O. , Jing-En Luan , Yiyi Ma
Published: March 2010

The reliability of the flip chip package is strongly influenced by underfill, which has a much higher coefficient of thermal expansion (CTE) compared with other packaging materials and leads to large thermomechanical stresses developed during the assembly processes. Thermal expansion mismatch between different materials causes interface delamination between epoxy molding compound and silicon die as well as interface delamination between underfill and silicon die. The main objective of this study is to investigate the effects of underfill material properties, fillet height, and silicon die thickness on the interface delamination between epoxy molding compound and silicon die during a lead-free solder reflow process based on the modified virtual crack closure method. Based on finite element analysis and experiment study, it can be concluded that the energy release rates at reflow temperature are the suitable criteria for the estimation of interface delamination. Furthermore, it is found that underfill material properties (elastic modulus, CTE, and chemical cure shrinkage), fillet height, and silicon die thickness can be optimized to reduce the risk of interface delamination between epoxy molding compound and silicon die in the flip chip ball grid array package.
Teaching Physics Using PhET Simulations
Authors: Wieman C. E. , Adams W. K. , Loeblein P. , Perkins K. K.
Published: March 2010

PhET Interactive Simulations (sims) are now being widely used in teaching physics and chemistry. Sims can be used in many different educational settings, including lecture, individual or small group inquiry activities, homework, and lab. Here we will highlight a few ways to use them in teaching, based on our research1 and experiences using them in high school and college classes. On our website we have a more complete guide to using PhET sims in the classroom: phet.colorado.edu/teacher_ideas/classroom-use.php.
Three-Dimensional Invisibility Cloak at Optical Wavelengths
Authors: Ergin Tolga , Stenger Nicolas , Brenner Patrice , Pendry John B. , Wegener Martin
Published: March 2010

Hidden Under the Carpet

Transformation optics, combined with the ability to fabricate structures with complex refractive index profiles, allow materials to be formed with fascinating optical properties, such as cloaks where both the object and the cloak concealing the object are rendered invisible. To date, the cloaks have been restricted to two dimensions, which limits realistic applications. Based on a photonic crystal structure with a polymer filling the empty space,

Ergin
et al.

(p.
337
, published online 18 March) have designed, fabricated, and realized a three-dimensional cloak operating at optical wavelengths.
MIXED FINITE ELEMENT METHODS FOR LINEAR VISCOELASTICITY USING WEAK SYMMETRY
Authors: ROGNES MARIE E. , WINTHER RAGNAR
Published: March 2010

Small deformations of a viscoelastic body are considered through the linear Maxwell and Kelvin–Voigt models in the quasi-static equilibrium. A robust mixed finite element method, enforcing the symmetry of the stress tensor weakly, is proposed for these equations on simplicial tessellations in two and three dimensions. A priori error estimates are derived and numerical experiments presented. The approach can be applied to general models for linear viscoelasticity and thus offers a unified framework.
ON MODULES OVER GROUP RINGS OF LOCALLY SOLUBLE GROUPS WITH RANK RESTRICTIONS ON SOME SYSTEMS OF SUBGROUPS
Authors: Dashkova O. Yu.
Published: March 2010

We consider a DG-module A over a Dedekind domain D. Let G be a group having infinite section p-rank (or infinite 0-rank) such that CG(A) = 1. It is known that if A is not an artinian D-module then for every proper subgroup H, the quotient A/CA(H) is an artinian D-module for every proper subgroup H of infinite section p-rank (or infinite 0-rank respectively). In this paper, it is proved that if G is a locally soluble group, then G is soluble. Some properties of soluble groups of this type are also obtained.
THE DYNAMICAL SYSTEMS METHOD FOR SOLVING NONLINEAR EQUATIONS WITH MONOTONE OPERATORS
Authors: Hoang N. S. , Ramm A. G.
Published: March 2010

A review of the authors' results is given. Several methods are discussed for solving nonlinear equations F(u) = f, where F is a monotone operator in a Hilbert space, and noisy data are given in place of the exact data. A discrepancy principle for solving the equation is formulated and justified. Various versions of the Dynamical Systems Method (DSM) for solving the equation are formulated. These versions of the DSM include a regularized Newton-type method, a gradient-type method, and a simple iteration method. A priori and a posteriori choices of stopping rules for these methods are proposed and justified. Convergence of the solutions, obtained by these methods, to the minimal norm solution to the equation F(u) = f is proved. Iterative schemes with a posteriori choices of stopping rule corresponding to the proposed DSM are formulated. Convergence of these iterative schemes to a solution to equation F(u) = f is justified. New nonlinear differential inequalities are derived and applied to a study of large-time behavior of solutions to evolution equations. Discrete versions of these inequalities are established.
PRIMENESS IN MODULE CATEGORY
Authors: Van Sanh Nguyen , Anh Vu Nguyen , Ahmed K. F. U. , Asawasamrit S. , Thao Le Phuong
Published: March 2010

We introduce the notion of prime submodules of a given right R-module and describe all properties of them as a generalization of prime ideals in associative rings.
HIGHER PRODUCT PYTHAGORAS NUMBERS OF SKEW FIELDS
Authors: Velušček Dejan
Published: March 2010

We introduce the n–th product Pythagoras number p n(D), the skew field analogue of the n–th Pythagoras number of a field. For a valued skew field (D, v) where v has the property of preserving sums of permuted products of n–th powers when passing to the residue skew field k v and where Newton's lemma holds for polynomials of the form Xn - a, a ∈ 1 + I v , p n(D) is bounded above by either p n( k v ) or p n( k v ) + 1. Spherical completeness of a valued skew field (D, v) implies that the Newton's lemma holds for Xn - a, a ∈ 1 + I v but the lemma does not hold for arbitrary polynomials. Using the above results we deduce that p n (D((G))) = p n(D) for skew fields of generalized Laurent series.
Fast min-hashing indexing and robust spatio-temporal matching for detecting video copies
Authors: Chiu Chih-Yi , Wang Hsin-Min , Chen Chu-Song
Published: March 2010

The increase in the number of video copies, both legal and illegal, has become a major problem in the multimedia and Internet era. In this article, we propose a novel method for detecting various video copies in a video sequence. To achieve fast and robust detection, the method fully integrates several components, namely the min-hashing signature to compactly represent a video sequence, a spatio-temporal matching scheme to accurately evaluate video similarity compiled from the spatial and temporal aspects, and some speedup techniques to expedite both min-hashing indexing and spatio-temporal matching. The results of experiments demonstrate that, compared to several baseline methods with different feature descriptors and matching schemes, the proposed method which combines both global and local feature descriptors yields the best performance when encountering a variety of video transformations. The method is very fast, requiring approximately 0.06 seconds to search for copies of a thirty-second video clip in a six-hour video sequence.
The case for a versatile storage system
Authors: Al-Kiswany Samer , Gharaibeh Abdullah , Ripeanu Matei
Published: March 2010

Storage systems in emerging large-scale (a.k.a. peta-scale) computing systems often introduce a performance or scalability bottleneck. To deal with these limitations we propose a new operational approach: versatile storage, an application-optimized and highly configurable storage system that harnesses node-local resources, is configured and deployed at application deployment time, and has a lifetime dependent on the application lifetime. Our prototype evaluation, using synthetic and application-level benchmarks, on a small cluster as well as on a 96K processor machine, provides evidence that the versatile storage approach can bring valuable benefits to large scale deployments in terms of storage system performance and scalability.
On the energy (in)efficiency of Hadoop clusters
Authors: Leverich Jacob , Kozyrakis Christos
Published: March 2010

Distributed processing frameworks, such as Yahoo!'s Hadoop and Google's MapReduce, have been successful at harnessing expansive datacenter resources for large-scale data analysis. However, their effect on datacenter energy efficiency has not been scrutinized. Moreover, the filesystem component of these frameworks effectively precludes scale-down of clusters deploying these frameworks (i.e. operating at reduced capacity). This paper presents our early work on modifying Hadoop to allow scale-down of operational clusters. We find that running Hadoop clusters in fractional configurations can save between 9% and 50% of energy consumption, and that there is a tradeoff between performance energy consumption. We also outline further research into the energy-efficiency of these frameworks.
Low-power amdahl-balanced blades for data intensive computing
Authors: Szalay Alexander S. , Bell Gordon C. , Huang H. Howie , Terzis Andreas , White Alainna
Published: March 2010

Enterprise and scientific data sets double every year, forcing similar growths in storage size and power consumption. As a consequence, current system architectures used to build data warehouses are about to hit a power consumption wall. In this paper we propose an alternative architecture comprising large number of so-called Amdahl blades that combine energy-efficient CPUs with solid state disks to increase sequential read I/O throughput by an order of magnitude while keeping power consumption constant. We also show that while keeping the total cost of ownership constant, Amdahl blades offer five times the throughput of a state-of-theart computing cluster for data-intensive applications. Finally, using the scaling laws originally postulated by Amdahl, we show that systems for data-intensive computing must maintain a balance between low power consumption and per-server throughput to optimize performance perWatt.
Schlafen 3 induction by cyclic strain regulates intestinal epithelial differentiation
Authors: Yuan Lisi , Yu Yingjie , Sanders Matthew A. , Majumdar Adhip P. N. , Basson Marc D.
Published: March 2010

The intestinal epithelium is subjected to repetitive deformation during normal gut function by peristalsis and villous motility. In vitro, cyclic strain promotes intestinal epithelial proliferation and induces an absorptive phenotype characterized by increased dipeptidyl dipeptidase (DPPIV) expression. Schlafen 3 is a novel gene recently associated with cellular differentiation. We sought to evaluate whether Schlafen 3 mediates the effects of strain on the differentiation of intestinal epithelial cell (IEC)-6 in the absence or presence of cyclic strain. Strain increased Schlafen 3 mRNA and protein. In cells transfected with a control-nontargeting siRNA, strain increased DPPIV-specific activity. However, Schlafen 3 reduction by siRNA decreased basal DPPIV and prevented any stimulation of DPPIV activity by strain. Schlafen 3 reduction also prevented DPPIV induction by sodium butyrate (1 mM) or transforming growth factor (TGF)-β (0.1 ng/ml), two unrelated differentiating stimuli. However, Schlafen-3 reduction by siRNA did not prevent the mitogenic effect of strain or that of EGF. Blocking Src and phosphatidyl inositol (PI3)-kinase prevented strain induction of Schlafen 3, but Schlafen 3 induction required activation of p38 but not ERK. These results suggest that cyclic strain induces an absorptive phenotype characterized by increased DPPIV activity via Src-, p38-, and PI3-kinase-dependent induction of Schlafen 3 in rat IEC-6 cells on collagen, whereas Schlafen 3 may also be a key factor in the induction of intestinal epithelial differentiation by other stimuli such as sodium butyrate or TGF-β. The induction of Schlafen 3 or its human homologs may modulate intestinal epithelial differentiation and preserve the gut mucosa during normal gut function.
Increased intramuscular lipid synthesis and low saturation relate to insulin sensitivity in endurance-trained athletes
Authors: Bergman Bryan C. , Perreault Leigh , Hunerdosse Devon M. , Koehler Mary C. , Samek Ali M. , Eckel Robert H.
Published: March 2010

Intramuscular triglyceride (IMTG) has received considerable attention as a potential mechanism promoting insulin resistance. Endurance-trained athletes have high amounts of IMTG but are insulin sensitive, suggesting IMTG content alone does not change insulin action. Recent data suggest increased muscle lipid synthesis protects against fat-induced insulin resistance. We hypothesized that rates of IMTG synthesis at rest would be increased in athletes compared with controls. Eleven sedentary men and 11 endurance-trained male cyclists participated in this study. An intravenous glucose tolerance test was performed to assess insulin action. After 3 days of dietary control and an overnight fast, [13C16]palmitate was infused at 0.0174 μmol·kg−1·min−1for 4 h, followed by a muscle biopsy to measure isotope incorporation into IMTG and diacylglycerol. Compared with controls, athletes were twice as insulin sensitive ( P = 0.004) and had a significantly greater resting IMTG concentration (athletes: 20.4 ± 1.6 μg IMTG/mg dry wt, controls: 14.5 ± 1.8 μg IMTG/mg dry wt, P = 0.04) and IMTG fractional synthesis rate (athletes: 1.56 ± 0.37%/h, controls: 0.61 ± 0.15%/h, P = 0.03). Stearoyl-CoA desaturase 1 mRNA expression ( P = 0.02) and protein content ( P = 0.03) were also significantly greater in athletes. Diacylglycerol, but not IMTG, saturation was significantly less in athletes compared with controls ( P = 0.002). These data indicate endurance-trained athletes have increased synthesis rates of skeletal muscle IMTG and decreased saturation of skeletal muscle diacylglycerol. Increased synthesis rates are not due to recovery from exercise and are likely adaptations to chronic endurance exercise training.
A common haplotype and the Pro582Ser polymorphism of the hypoxia-inducible factor-1α (HIF1A) gene in elite endurance athletes
Authors: Döring Frank , Onur Simone , Fischer Alexandra , Boulay Marcel R. , Pérusse Louis , Rankinen Tuomo , Rauramaa Rainer , Wolfarth Bernd , Bouchard Claude
Published: March 2010

Hypoxia-inducible factor-1α ( HIF1A) is a transcription factor regulating several genes in response to hypoxic stimuli. HIF1A target genes code for proteins involved in oxygen transport, glycolytic enzymes, and glucose transporters. We investigated whether single-nucleotide polymorphisms and haplotypes in the HIF1A gene are associated with endurance performance in the Genathlete cohort, which includes 316 Caucasian male elite endurance athletes (EEA) with a maximal oxygen uptake of 79.0 ± 3.5 ml·kg−1·min−1 (mean ± SD) and 304 Caucasian male sedentary controls with a maximal oxygen uptake of 40.1 ± 7.0 ml·kg−1·min−1. Six single-nucleotide polymorphisms (rs1951795, rs11158358, rs2301113, rs11549465, rs115494657, rs17099207) were genotyped with the TaqMan system. We found a nominal significant tendency for a difference between the two groups for HIF1A Pro582Ser (rs11549465) genotype distributions ( P χ2 = 0.017). Homozygotes of the Pro genotype were slightly more frequent in athletes than in controls (84 vs. 75%). Compared with Ser carriers, the odds ratio (OR) of being an EEA in Pro/Pro homozygotes was 1.77 [95% confidence interval (CI): 1.18–2.67, P = 0.006] compared with the other genotypes. A common HIF1A haplotype (frequency: 15%), including the rs11549465 Pro allele and the minor A allele of rs17099207 in the 3′ flanking region of the gene, showed a significant association with EEA status (OR: 2.37, 95% CI: 1.21–4.66, P = 0.012), whereas the most prevalent haplotype (frequency: 59%) comprising the rs11549465 Pro allele and the major G allele of rs1709920 showed no association with EEA status (OR: 0.93, 95% CI: 0.58–1.50, P = 0.769). We found preliminary evidence that the HIF1A Pro582Ser polymorphism and a common haplotype of the HIF1A gene may be associated with EEA status in Caucasian men.
Reduction of total lung capacity in obese men: comparison of total intrathoracic and gas volumes
Authors: Watson R. A. , Pride N. B. , Thomas E. Louise , Fitzpatrick J. , Durighel G. , McCarthy J. , Morin S. X. , Ind P. W. , Bell J. D.
Published: March 2010

Restriction of total lung capacity (TLC) is found in some obese subjects, but the mechanism is unclear. Two hypotheses are as follows: 1) increased abdominal volume prevents full descent of the diaphragm; and 2) increased intrathoracic fat reduces space for full lung expansion. We have measured total intrathoracic volume at full inflation using magnetic resonance imaging (MRI) in 14 asymptomatic obese men [mean age 52 yr, body mass index (BMI) 35–45 kg/m2] and 7 control men (mean age 50 yr, BMI 22–27 kg/m2). MRI volumes were compared with gas volumes at TLC. All measurements were made with subjects supine. Obese men had smaller functional residual capacity (FRC) and FRC-to-TLC ratio than control men. There was a 12% predicted difference in mean TLC between obese (84% predicted) and control men (96% predicted). In contrast, differences in total intrathoracic volume (MRI) at full inflation were only 4% predicted TLC (obese 116% predicted TLC, control 120% predicted TLC), because mediastinal volume was larger in obese than in control [heart and major vessels (obese 1.10 liter, control 0.87 liter, P = 0.016) and intrathoracic fat (obese 0.68 liter, control 0.23 liter, P < 0.0001)]. As a consequence of increased mediastinal volume, intrathoracic volume at FRC in obese men was considerably larger than indicated by the gas volume at FRC. The difference in gas volume at TLC between the six obese men with restriction, TLC < 80% predicted (OR), and the eight obese men with TLC > 80% predicted (ON) was 26% predicted TLC. Mediastinal volume was similar in OR (1.84 liter) and ON (1.73 liter), but total intrathoracic volume was 19% predicted TLC smaller in OR than in ON. We conclude that the major factor restricting TLC in some obese men was reduced thoracic expansion at full inflation.