bluuebunny/crossref_metadata_2025 huggingface dataset:
Multidisciplinary students and instructors
Authors: Sturtevant Nathan R. , Hoover H. James , Schaeffer Jonathan , Gouglas Sean , Bowling Michael H. , Southey Finnegan , Bouchard Matthew , Zabaneh Ghassan
Published: March 2008

Computer games are a multi-billion dollar industry and have become an important part of our private and social lives. It is only natural, then, that the technology used to create games should become part of a computing science curriculum. However, game development is more than a massive programming endeavor. Today's games are largely about generating content within multidisciplinary teams. CMPUT 250 is a new computing science course at the University of Alberta that emphasizes creating games in multidisciplinary teams. This paper describes our experiences with the course, emphasizing the issues of multidisciplinary interactions: teaching, teamwork, and evaluation.
An interdisciplinary major emphasizing multimedia
Authors: Spradling Carol , Strauch Jody , Warner Craig
Published: March 2008

In this paper, we describe a new interdisciplinary Bachelor of Science degree in Interactive Digital Media at Northwest Missouri State University, developed and maintained by three departments, Art, Computer Science/Information Systems and Mass Communication. The majors share a common core of courses taught by the three departments with each having its own concentration of Visual Imaging, Computer Science Programming and New Media, respectively. This paper describes the process utilized to develop the major, the curriculum, some observations and the process to maintain the major.
A system for developing tablet pc applications for education
Authors: Kamin Sam , Hines Michael , Peiper Chad , Capitanu Boris
Published: March 2008

We describe a new system for building Tablet PC-based classroom software. The system, called SLICE, is built for extensibility, using a unique "explicit state" model.

Applications developed thus far include presentation, classroom interaction, shared code review, and exam grading.

The paper presents an overview of the system and describes these four applications. It then explains the extensibility model, showing how users can add new features.
Developing inclusive outreach activities for students with visual impairments
Authors: Ludi Stephanie Ann , Reichlmayr Thomas
Published: March 2008

Despite advances in assistive technology, relatively few visually impaired students participate in university-level computing courses. Significant factors in this under representation include lack of relevant precollege preparation, lack of role models, access to resources, and the highly visual nature of modern computing. This paper describes the development of inclusive activities and materials for use in a summer workshop for precollege students with visual impairments. All activities utilized commercial technologies in the areas of robotics and programming using Lego Mindstorms NXT. The workshop activities are designed to provide a foundation in computing that encourages students to pursue computing in high school and beyond. In addition to activity design, initial results and lessons learned from the summer workshop will be presented.
Improving retention and graduate recruitment through immersive research experiences for undergraduates
Authors: Dahlberg Teresa , Barnes Tiffany , Rorrer Audrey , Powell Eve , Cairco Lauren
Published: March 2008

Research experiences for undergraduates are considered an effective means for increasing student retention and encouraging undergraduate students to continue on to graduate school. However, managing a cohort of undergraduate researchers, with varying skill levels, can be daunting for faculty advisors. We have developed a program to engage students in research and outreach in visualization, virtual reality, networked robotics, and interactive games. Our program immerses students into the life of a lab, employing a situated learning approach that includes tiered mentoring and collaboration to enable students at all levels to contribute to research. Students work in research teams comprised of other undergraduates, graduate students and faculty, and participate in professional development and social gatherings within the larger cohort. Results from our first two years indicate this approach is manageable and effective for increasing students' ability and desire to conduct research.
Can great research be taught?
Authors: Feamster Nick , Gray Alexander
Published: March 2008

This paper describes a course we have developed for preparing new Ph.D. students in computer science for a career in research. The course is intended to teach the skills needed for research and independent work, prepare students psychologically and socially for years lying before them, and help them find a good Ph.D. topic by providing principles and examples. In this course, we emphasize and encourage impact through cross-disciplinary research and broader societal outreach. To our knowledge, the course represents a first-of-its-kind systematic introduction to a graduate research career. This paper describes our high-level goals for this curricular initiative, the structure of the course (including lecture components and assignments), and the challenges we faced in developing this course. As we continue to develop this course, which is now in its second year, we hope it will serve as a model "introduction of Ph.D. research" course for other computer science departments.
A citation analysis of the sigcse 2007 proceedings
Authors: Lister Raymond , Box Ilona
Published: March 2008

This paper identifies the most commonly cited conferences, journals and books among the 1398 citations made in the 122 publications of the SIGCSE 2007 proceedings. The SIGCSE 2007 authors cited a very large array of conferences, journals and books, but the majority are only cited within a single paper. There are only a very small set of journals and conferences cited frequently. Most books cited are concerned with technical information or are textbooks. Only 2% of books are concerned with computer science education and 23% with education in general. The picture that emerges from this citation analysis is that the SIGCSE community does not have a substantial core set of educational literature. Also, the epistemology of the SIGCSE community is primarily objectivist, with a focus on content, rather than a constructivist, student-centered focus on learning.
A cross-domain visual learning engine for interactive generation of instructional materials
Authors: Subramanian K. R. , Cassen T.
Published: March 2008

We present the design and development of a Visual Learning Engine, a tool that can form the basis for interactive development of visually rich teaching and learning modules across multiple disciplines. The engine has three key features that makes it powerful and cross-disciplinary, (1) it is based on a finite state machine model, that supports concepts presented in any defined sequence, (2) instructional modules are designed and generated interactively using graphical interface widgets, facilitating non-programmers to use the system, and (3) ability to simultaneously present concepts and their visual representation that allows for a more intuitive and exploratory learning experience. We demonstrate a prototype of the learning engine by testing it on examples from Computer Science(sorting)algorithms, recursion) and Electrical Engineering (signal manipulations).
Test-driven learning in early programming courses
Authors: Janzen David , Saiedian Hossein
Published: March 2008

Coercing new programmers to adopt disciplined development practices such as thorough unit testing is a challenging endeavor. Test-driven development (TDD) has been proposed as a solution to improve both software design and testing. Test-driven learning (TDL) has been proposed as a pedagogical approach for teaching TDD without imposing significant additional instruction time.

This research evaluates the effects of students using a test-first (TDD) versus test-last approach in early programming courses, and considers the use of TDL on a limited basis in CS1 and CS2. Software testing, programmer productivity, programmer performance, and programmer opinions are compared between test-first and test-last programming groups. Results from this research indicate that a test-first approach can increase student testing and programmer performance, but that early programmers are very reluctant to adopt a test-first approach, even after having positive experiences using TDD. Further, this research demonstrates that TDL can be applied in CS1/2, but suggests that a more pervasive implementation of TDL may be necessary to motivate and establish disciplined testing practice among early programmers.
Formation and Properties of Quasicrystals
Authors: Louzguine-Luzgin D.V. , Inoue A.
Published: March 2008

This article summarizes the general structural features and important properties of quasicrystals, a relatively new class of materials belonging to solid-state substances. Quasicrystals, which have a long-range quasiperiodic order but no three-dimensional translational periodicity, are structurally different from both conventional crystals and glassy solids. Although applications are still highly limited, quasicrystals are attracting significant attention as a structual constituent of mixed-phase materials exhibiting high strength together with certain ductility and can be applied as structural materials.
Active and Passive Immunotherapy for Neurodegenerative Disorders
Authors: Brody David L. , Holtzman David M.
Published: March 2008

Immunotherapeutic strategies to combat neurodegenerative disorders have galvanized the scientific community since the first dramatic successes in mouse models recreating aspects of Alzheimer disease (AD) were reported. However, initial human trials of active amyloid-beta (Aβ) vaccination were halted early because of a serious safety issue: meningoencephalitis in 6% of subjects. Nonetheless, some encouraging preliminary data were obtained, and rapid progress has been made toward developing alternative, possibly safer active and passive immunotherapeutic approaches for several neurodegenerative conditions. Many of these are currently in human trials for AD. Despite these advances, our understanding of the essential mechanisms underlying the effects seen in preclinical models and human subjects is still incomplete. Antibody-induced phagocytosis of pathological protein deposits, direct antibody-mediated disruption of aggregates, neutralization of toxic soluble proteins, a shift in equilibrium toward efflux of specific proteins from the brain, cell-mediated immune responses, and other mechanisms may all play roles depending on the specific immunotherapeutic scenario.
A moderate increase in carnitine palmitoyltransferase 1a activity is sufficient to substantially reduce hepatic triglyceride levels
Authors: Stefanovic-Racic Maja , Perdomo German , Mantell Benjamin S. , Sipula Ian J. , Brown Nicholas F. , O'Doherty Robert M.
Published: March 2008

Nonalcoholic fatty liver disease (NAFLD), hypertriglyceridemia, and elevated free fatty acids are present in the majority of patients with metabolic syndrome and type 2 diabetes mellitus and are strongly associated with hepatic insulin resistance. In the current study, we tested the hypothesis that an increased rate of fatty acid oxidation in liver would prevent the potentially harmful effects of fatty acid elevation, including hepatic triglyceride (TG) accumulation and elevated TG secretion. Primary rat hepatocytes were transduced with adenovirus encoding carnitine palmitoyltransferase 1a (Adv-CPT-1a) or control adenoviruses encoding either β-galactosidase (Adv-β-gal) or carnitine palmitoyltransferase 2 (Adv-CPT-2). Overexpression of CPT-1a increased the rate of β-oxidation and ketogenesis by ∼70%, whereas esterification of exogenous fatty acids and de novo lipogenesis were unchanged. Importantly, CPT-1a overexpression was accompanied by a 35% reduction in TG accumulation and a 60% decrease in TG secretion by hepatocytes. There were no changes in secretion of apolipoprotein B (apoB), suggesting the synthesis of smaller, less atherogenic VLDL particles. To evaluate the effect of increasing hepatic CPT-1a activity in vivo, we injected lean or obese male rats with Adv-CPT-1a, Adv-β-gal, or Adv-CPT-2. Hepatic CPT-1a activity was increased by ∼46%, and the rate of fatty acid oxidation was increased by ∼44% in lean and ∼36% in obese CPT-1a-overexpressing animals compared with Adv-CPT-2- or Adv-β-gal-treated rats. Similar to observations in vitro, liver TG content was reduced by ∼37% (lean) and ∼69% (obese) by this in vivo intervention. We conclude that a moderate stimulation of fatty acid oxidation achieved by an increase in CPT-1a activity is sufficient to substantially reduce hepatic TG accumulation both in vitro and in vivo. Therefore, interventions that increase CPT-1a activity could have potential benefits in the treatment of NAFLD.
Inhibition of Ca2+signaling and glucagon secretion in mouse pancreatic α-cells by extracellular ATP and purinergic receptors
Authors: Tudurí Eva , Filiputti Eliane , Carneiro Everardo M. , Quesada Ivan
Published: March 2008

Glucagon secreted from pancreatic α-cells plays a critical role in glycemia, mainly by hepatic glucose mobilization. In diabetic patients, an impaired control of glucagon release can worsen glucose homeostasis. Despite its importance, the mechanisms that regulate its secretion are still poorly understood. Since α-cells are particularly sensitive to neural and paracrine factors, in this report we studied the role of purinergic receptors and extracellular ATP, which can be released from nerve terminals and β-cell secretory granules. Using immunocytochemistry, we identified in α-cells the P2 receptor subtype P2Y1, as well as the P1 receptors A1and A2A. In contrast, only P2Y1and A1receptors were localized in β-cells. To analyze the role of purinergic receptors in α-cell function, we studied their participation in Ca2+signaling. At low glucose concentrations, mouse α-cells exhibited the characteristic oscillatory Ca2+signals that lead to secretion. Application of ATP (1–10 μM) abolished these oscillations or reduced their frequency in α-cells within intact islets and isolated in culture. ATPγS, a nonhydrolyzable ATP derivative, indicated that the ATP effect was mainly direct rather than through ATP-hydrolytic products. Additionally, adenosine (1–10 μM) was also found to reduce Ca2+signals. ATP-mediated inhibition of Ca2+signaling was accompanied by a decrease in glucagon release from intact islets in contrast to the adenosine effect. Using pharmacological agonists, we found that only P2Y1and A2Awere likely involved in the inhibitory effect on Ca2+signaling. All these findings indicate that extracellular ATP and purinergic stimulation are effective regulators of the α-cell function.
PGC-1α's relationship with skeletal muscle palmitate oxidation is not present with obesity despite maintained PGC-1α and PGC-1β protein
Authors: Holloway Graham P. , Perry Christopher G. R. , Thrush A. Brianne , Heigenhauser George J. F. , Dyck David J. , Bonen Arend , Spriet Lawrence L.
Published: March 2008

Reduced skeletal muscle mitochondrial content and fatty acid oxidation are associated with obesity and insulin resistance. Although the exact mechanisms remain elusive, this may result from impaired mitochondrial biogenesis or reductions in the mitochondrial reticulum network. Therefore, the purpose of this study was to determine whether the protein contents of various transcription factors, including PGC-1α and PGC-1β and proteins associated with mitochondrial fusion events, were reduced in skeletal muscle of nine obese (BMI = 37.6 ± 2.2 kg/m−2) compared with nine age-matched lean (BMI = 23.3 ± 0.7 kg/m−2) women. The protein contents of PGC-1α, PGC-1β, PPARα, and tFAM were not reduced with obesity. In contrast, PPARγ was increased (+22%, P < 0.05) with obesity, and there was a trend toward an increase (+31%, P = 0.13) in PPARδ/β. In lean individuals, PGC-1α protein correlated with citrate synthase (CS; r = 0.67) and rates of palmitate oxidation ( r = 0.87), whereas PGC-1β correlated with PPARγ ( r = 0.90), PPARδ/β ( r = 0.63), and cytochrome c oxidase IV (COX-IV; r = 0.63). In obese individuals, the relationship between PGC-1α and CS was maintained ( r = 0.65); however, the associations between PGC-1α and palmitate oxidation ( r = −0.38) and PGC-1β with PPARγ ( r = 0.14), PPARδ/β ( r = 0.21), and COX-IV ( r = 0.01) were lost. In addition, mitofusin-1 (MFN-1), MFN-2, and dynamin-related protein-1 (DRP-1) total protein contents were not altered with obesity ( P > 0.05). These data suggest that altered regulation, and not reductions in the protein contents of transcription factors, is associated with insulin resistance. Also, it does not appear that alterations in the proteins associated with mitochondrial network formation and degradation can account for the observed decrease in mitochondrial content.
Transcriptional adaptation to Clcn5 knockout in proximal tubules of mouse kidney
Authors: Wright Jerry , Morales Marcelo M. , Sousa-Menzes Jackson , Ornellas Debora , Sipes Jennifer , Cui Yan , Cui Isabelle , Hulamm Phuson , Cebotaru Valeriu , Cebotaru Liudmila , Guggino William B. , Guggino Sandra E.
Published: March 2008

Dent disease has multiple defects attributed to proximal tubule malfunction including low-molecular-weight proteinuria, aminoaciduria, phosphaturia, and glycosuria. To understand the changes in kidney function of the Clc5 chloride/proton exchanger gene knockout mouse model of Dent disease, we examined gene expression profiles from proximal S1 and S2 tubules of mouse kidneys. We found many changes in gene expression not known previously to be altered in this disease. Genes involved in lipid metabolism, organ development, and organismal physiological processes had the greatest number of significantly changed transcripts. In addition, genes of catalytic activity and transporter activity also had a great number of changed transcripts. Overall, 720 genes are expressed differentially in the proximal tubules of the Dent Clcn5 knockout mouse model compared with those of control wild-type mice. The fingerprint of these gene changes may help us to understand the phenotype of Dent disease.
A Context‐Sensitive Active Contour for 2D Corpus Callosum Segmentation
Authors: He Qing , Duan Ye , Miles Judith , Takahashi Nicole
Published: March 2008

We propose a new context‐sensitive active contour for 2D corpus callosum segmentation. After a seed contour consisting of interconnected parts is being initialized by the user, each part will start to deform according to its own motion law derived from high‐level prior knowledge, and is constantly aware of its own orientation and destination during the deformation process. Experimental results demonstrate the accuracy and robustness of our algorithm.
A Common Fixed Point Theorem in "Equation missing" -Metric Spaces
Authors: Sedghi Shaban , Shobe Nabi , Zhou Haiyun
Published: March 2008

We give some new definitions of "Equation missing"-metric spaces and we prove a common fixed point theorem for a class of mappings under the condition of weakly commuting mappings in complete "Equation missing"-metric spaces. We get some improved versions of several fixed point theorems in complete "Equation missing"-metric spaces.
Further Properties ofβ-Pascu Convex Functions of Orderα
Authors: Güney H. Özlem , Sâlâgean Grigore Stefan
Published: March 2008

We obtain several further properties ofβ-Pascu convex functions of orderαwhich were recently introduced and studied by Ali et al. in (2006).
On Weak Statistical Convergence
Authors: Bhardwaj Vinod K. , Bala Indu
Published: March 2008

The main object of this paper is to introduce a new concept of weak statistically Cauchy sequence in a normed space. It is shown that in a reflexive space, weak statistically Cauchy sequences are the same as weakly statistically convergent sequences. Finally, weak statistical convergence has been discussed inlpspaces.
Analysis of Convective Straight and Radial Fins with Temperature-Dependent Thermal Conductivity Using Variational Iteration Method with Comparison with Respect to Finite Element Analysis
Authors: Coşkun Safa Bozkurt , Atay Mehmet Tarik
Published: March 2008

In order to enhance heat transfer between primary surface and the environment, radiating extended surfaces are commonly utilized. Especially in the case of large temperature differences, variable thermal conductivity has a strong effect on performance of such a surface. In this paper, variational iteration method is used to analyze convective straight and radial fins with temperature-dependent thermal conductivity. In order to show the efficiency of variational iteration method (VIM), the results obtained from VIM analysis are compared with previously obtained results using Adomian decomposition method (ADM) and the results from finite element analysis. VIM produces analytical expressions for the solution of nonlinear differential equations. However, these expressions obtained from VIM must be tested with respect to the results obtained from a reliable numerical method or analytical solution. This work assures that VIM is a promising method for the analysis of convective straight and radial fin problems.
On a Cubic Equation and a Jensen-Quadratic Equation
Authors: Bae Jae-Hyeong , Park Won-Gil
Published: March 2008

We obtain the general solutions of the cubic functional equation3[g(x+y)+g(x−y)+6g(x)]=2g(2x+y)+2g(2x−y)+g(−x−y)+g(−x+y)+6g(−x)and the Jensen-quadratic functional equationf((x+y)/2,z+w)+f((x+y)/2,z−w)=f(x,z)+f(x,w)+f(y,z)+f(y,w).
How Should an Increase in Alkaline Phosphatase Activity Be Interpreted?
Authors: Hawkins Denise , Abrahamse Heidi
Published: March 2008

Low‐level laser therapy, commonly known as LLLT, is the application of low power, monochromatic, and coherent light to injuries and lesions to stimulate healing and give pain relief. There are conflicting reports in the literature regarding the role of ALP.
Objective: this study aimed to compare the cellular responses of wounded human skin fibroblasts exposed to doses of 0.5 J/cm2, 2.5 J/cm2, 5 J/cm2, or 16 J/cm2 using LLLT with a Helium‐Neon laser (632.8 nm, 18.8 mW power output, 2.07 mW/cm2 power density, and 3.4 cm diameter spot size or area 9.1 cm2) to elucidate the role of alkaline phosphatase (ALP) in cell proliferation.
Methods: cellular responses to laser irradiation were evaluated using ALP enzyme activity, LDH membrane integrity, neutral red for cell proliferation, optical density at 540 nm, and basic fibroblast growth factor (bFGF) expression.
Results: results suggest that an increase in ALP is negatively correlated with cell growth depending on the concentration of growth factors in the medium. Results also indicate that an increase in ALP may be related to cellular damage.
Conclusion: since the exact role of ALP is unknown, the ALP enzyme activity assay should be considered in conjunction with other cell proliferation assays such as neutral red, optical density, or more specifically bFGF expression.
Switching Systems: Active Mode Recognition, Identification of the Switching Law
Authors: Domlan Elom Ayih , Ragot José , Maquin Didier
Published: March 2008

The problem of the estimation of the discrete state of a switching system is studied. The knowledge of the switching law is essential for this kind of system as it simplifies their manipulation for control purposes. This paper investigates the use of a model-based diagnosis method for the determination of the active mode at each time point based on the system input/output data. The issue of the parametric identification of the switching law is also addressed.
Synthesis, X-Ray Structure, and Characterization of a Complex Containing the Hexakis(urea)cobalt(II) Cation and Lattice Urea Molecules
Authors: Drakopoulou Labrini , Papatriantafyllopoulou Constantina , Terzis Aris , Perlepes Spyros P. , Manessi-Zoupa Evy , Papaefstathiou Giannis S.
Published: March 2008

The 12: 1 reaction of urea (U) with CoI2in EtOH yielded the “clathrate-coordination” compound[CoU6]I2·4U (1). The complex crystallizes in the monoclinic space group P21/c. The lattice constants area= 9.844(4),b= 7.268(3),c= 24.12(1) Å, andβ=98.12(1)∘. The crystal structure determination demonstrates the existence of octahedral[CoU6]2+cations,I-counterions, and two different types (twoU1and twoU2) of hydrogen-bonded, lattice urea molecules. The[CoU6]2+cations and theU1lattice molecules form two-dimensional hydrogen-bonded layers which are parallel to theabplane. TheI-anions are placed above and below each layer, and are hydrogen bonded both toU1molecules and[CoU6]2+cations. EachU2molecule is connected to a[CoU6]2+cation through anN–H⋯Ohydrogen bond resulting in a three-dimensional network. Room temperature magnetic susceptibility and spectroscopic (solid-state UV/Vis, IR, Raman) data of1are discussed in terms of the nature of bonding and the known structure.
Common Fixed Points of Mappings and Set-Valued Mappings in Symmetric Spaces with Application to Probabilistic Spaces
Authors: Aamri M. , Bassou A. , Bennani S. , El Moutawakil D.
Published: March 2008

The main purpose of this paper is to give some common fixed point theorems of mappings and set-valued mappings of a symmetric space with some applications to probabilistic spaces. In order to get these results, we define the concept of E-weak compatibility between set-valued and single-valued mappings of a symmetric space.
Forgery Detection in Dynamic Signature Verification by Entailing Principal Component Analysis
Authors: Sayeed Shohel , Andrews S. , Besar Rosli , Kiong Loo Chu
Published: March 2008

The critical analysis of the data glove-based signature identification and forgery detection system emphasizes the essentiality of noise-free signals for input. Lucid inputs are expected for the accuracy enhancement and performance. The raw signals that are captured using 14- and 5-electrode data gloves for this purpose have a noisy and voluminous nature. Reduction of electrodes may reduce the volume but it may also reduce the efficiency of the system. The principal component analysis (PCA) technique has been used for this purpose to condense the volume and enrich the operational data by noise reduction without affecting the efficiency. The advantage of increased discernment in between the original and forged signatures using 14-electrode glove over 5-electrode glove has been discussed here and proved by experiments with many subjects. Calculation of the sum of mean squares of Euclidean distance has been used to project the advantage of our proposed method. 3.1% and 7.5% of equal error rates for 14 and 5 channels further reiterate the effectiveness of this technique.
On the Lower Bound for the Number of Real Roots of a
Random Algebraic Equation
Authors: Uno Takashi
Published: March 2008

We estimate a lower bound for the number of real roots of a random alegebraic equation whose random coeffcients are dependent normal random variables.
Operator Representation of Fermi-Dirac and Bose-Einstein Integral Functions with Applications
Authors: Chaudhry M. Aslam , Qadir Asghar
Published: March 2008

Fermi-Dirac and Bose-Einstein functions arise as quantum statistical distributions. The Riemann zeta function and its extension, the polylogarithm function, arise in the theory of numbers. Though it might not have been expected, these two sets of functions belong to a wider class of functions whose members have operator representations. In particular, we show that the Fermi-Dirac and Bose-Einstein integral functions are expressible as operator representations in terms of themselves. Simpler derivations of previously known results of these functions are obtained by their operator representations.
Electron Transfer Mediators for Photoelectrochemical Cells Based on Cu(I) Metal Complexes
Authors: Brugnati Michele , Caramori Stefano , Cazzanti Silvia , Marchini Luca , Argazzi Roberto , Bignozzi Carlo A.
Published: March 2008

The preparation and the photoelectrochemical characterization of a series of bipyridine and pyridyl-quinoline Cu(I) complexes, used as electron transfer mediators in regenerative photoelectrochemical cells, are reported. The best performing mediators produced maximum IPCEs of the order of 35–40%. The J-V curves recorded under monochromatic light showed that the selected Cu(I)/(II) couples generated higher Vocs and fill factors compared to an equivalentI-/I3-cell, due to a decreased dark current.
Some External Characterizations of SV-Rings and Hereditary Rings
Authors: Haily A. , Rahnaoui H.
Published: March 2008

We introduce a new class of rings which we callAI-rings. By applying this property to endomorphism rings, we give characterizations of semi-ArtinianV-rings and hereditary rings.
Regulatory T Cells and Human Disease
Authors: Cools Nathalie , Ponsaerts Peter , Van Tendeloo Viggo F. I. , Berneman Zwi N.
Published: March 2008

The main function of our immune system is to protect us from invading pathogens and microorganisms by destroying infected cells, while minimizing collateral damage to tissues. In order to maintain this balance between immunity and tolerance, current understanding of the immune system attributes a major role to regulatory T cells (Tregs) in controlling both immunity and tolerance. Various subsets of Tregs have been identified based on their expression of cell surface markers, production of cytokines, and mechanisms of action. In brief, naturally occurring thymic-derivedCD4+CD25+Tregs are characterized by constitutive expression of the transcription factor FOXP3, while antigen-induced or adaptive Tregs are mainly identified by expression of immunosuppressive cytokines (interleukin-10 (IL-10) and/or transforming growth factor-β(TGF-β)). While Tregs in normal conditions regulate ongoing immune responses and prevent autoimmunity, imbalanced function or number of these Tregs, either enhanced or decreased, might lead, respectively, to decreased immunity (e.g., with tumor development or infections) or autoimmunity (e.g., multiple sclerosis). This review will discuss recent research towards a better understanding of the biology of Tregs, their interaction with other immune effector cells, such as dendritic cells, and possible interventions in human disease.
Design of Biotin-Functionalized Luminescent Quantum Dots
Authors: Susumu Kimihiro , Uyeda H. Tetsuo , Medintz Igor L. , Mattoussi Hedi
Published: March 2008

We report the design and synthesis of a tetraethylene glycol- (TEG-) based bidentate ligand functionalized with dihydrolipoic acid (DHLA) and biotin (DHLA—TEG—biotin) to promote biocompatibility of luminescent quantum dots (QD's). This new ligand readily binds to CdSe—ZnS core-shell QDs via surface ligand exchange. QDs capped with a mixture of DHLA and DHLA—TEG—biotin or polyethylene glycol- (PEG-) (molecular weight average∼600) modified DHLA (DHLA—PEG600) and DHLA—TEG—biotin are easily dispersed in aqueous buffer solutions. In particular, homogeneous buffer solutions of QDs capped with a mixture of DHLA—PEG600 and DHLA—TEG—biotin that are stable over broad pH range have been prepared. QDs coated with mixtures of DHLA/DHLA—TEG—biotin and with DHLA—PEG600/DHLA—TEG—biotin were tested in surface binding assays and the results indicate that biotin groups on the QD surface interact specifically with NeutrAvidin-functionalized microtiter well plates.
Synthesis ofβ-Phase (Bi2O3)1-x(Dy2O3)x(0.01<x<0.10) System and Measurement of Oxygen Ionic Conductivity
Authors: Yilmaz Serdar , Turkoglu Orhan , Belenli Ibrahim
Published: March 2008

β-phase (Bi2O3)1-x(Dy2O3)xsystem with tetragonal structure is synthesized for0.01<x<0.10molar doping. Unit cell parameters increased with increasing the doping. We have studied the dependence of total electrical conductvity on temperature, doping concentration ofβ-phase systems. The phase transition which manifests itself by the jump in the conductivity curve was also verified by DTA and both measurements are rather compatible. The electrical conductivity curves ofβ-phase structure revealed regular increase in the form of an Arrhenius curve. The activation energies are calculated from these graphs.Bi2O3-basedDy2O3doped ceramics show ionic oxygen conductivity. The conductivity increased as the doping concentration increased. The highest value of conductivity is 0.006 0.006ohm-1cm-1(600∘C)for theβ-phase (Bi2O3)0.91(Dy2O3)0.09(800∘C). The sample with the highest conductivity is (Bi2O3)0.91(Dy2O3)0.09(800∘C)binary system where 1.450 ohm−1cm−1(745∘C).
Stannic Oxide-Titanium Dioxide Coupled Semiconductor Photocatalyst Loaded with Polyaniline for Enhanced Photocatalytic Oxidation of 1-Octene
Authors: Nur Hadi , Misnon Izan Izwan , Wei Lim Kheng
Published: March 2008

Stannic oxide-titanium dioxide (SnO2–TiO2) coupled semiconductor photocatalyst loaded with polyaniline (PANI), a conducting polymer, possesses a high photocatalytic activity in oxidation of 1-octene to 1,2-epoxyoctane with aqueous hydrogen peroxide. The photocatalyst was prepared by impregnation ofSnO2and followed by attachment of PANI onto aTiO2powder to give sample PANI-SnO2–TiO2. The electrical conductivity of the system becomes high in the presence of PANI. Enhanced photocatalytic activity was observed in the case of PANI-SnO2–TiO2compared to PANI-TiO2,SnO2–TiO2, andTiO2. A higher photocatalytic activity in the oxidation of 1-octene on PANI-SnO2–TiO2thanSnO2–TiO2, PANI-TiO2, andTiO2can be considered as an evidence of enhanced charge separation of PANI-SnO2–TiO2photocatalyst as confirmed by photoluminescence spectroscopy. It suggests that photoinjected electrons are tunneled fromTiO2toSnO2and then to PANI in order to allow wider separation of excited carriers.
Design and Assessment of a Multiple Sensor Fault Tolerant Robust Control System
Authors: Yang S.S. , Chen J.
Published: March 2008

This paper presents an enhanced robust control design structure to realise fault tolerance towards sensor faults suitable for multi‐input‐multi‐output (MIMO) systems implementation. The proposed design permits fault detection and controller elements to be designed with considerations to stability and robustness towards uncertainties besides multiple faults environment on a common mathematical platform. This framework can also cater to systems requiring fast responses. A design example is illustrated with a fast, multivariable and unstable system, that is, the double inverted pendulum system. Results indicate the potential of this design framework to handle fast systems with multiple sensor faults.
Second Hankel Determinant for a Class of Analytic Functions Defined by Fractional Derivative
Authors: Mishra A. K. , Gochhayat P.
Published: March 2008

By making use of the fractional differential
operator due to Owa and Srivastava, a class of
analytic functions ℛλ(α, ρ)    (0 ≤ ρ ≤ 1,   0 ≤ λ < 1,     |α| < π/2) is introduced. The sharp bound for the nonlinear functional is found. Several basic properties such as inclusion, subordination,
integral transform, Hadamard product are also studied.
Bleeding Jejunal Diverticulosis in a Patient with Myasthenia Gravis
Authors: Zuber-Jerger I. , Endlicher E. , Kullmann F.
Published: March 2008

A seventy-year-old male presented with severe myasthenia gravis and an episode of obscure bleeding. There was a history of gastric ulcer leading to Billroth II surgery twenty-five years ago. Upper endoscopy revealed no pathology. Colonoscopy showed a few solitary diverticula and traces of old blood in the terminal ileum. Capsule endoscopy pictured red smear in the upper jejunum. Diverticula were seen as well. Suspecting bleeding jejunal diverticulosis double balloon enteroscopy was performed. The complete jejunal ascending loop and about 100 cm of the jejunum through the descending jejunal loop could be inspected. Large diverticula with fecoliths were found in both loops. Bleeding had ceased. The patient was discharged to neurology for optimizing therapy for myasthenia gravis.
Minimization of Tikhonov Functionals in Banach Spaces
Authors: Bonesky Thomas , Kazimierski Kamil S. , Maass Peter , Schöpfer Frank , Schuster Thomas
Published: March 2008

Tikhonov functionals are known to be well suited for obtaining regularized
solutions of linear operator equations. We analyze two iterative
methods for finding the minimizer of norm‐based Tikhonov functionals in
Banach spaces. One is the steepest descent method, whereby the iterations
are directly carried out in the underlying space, and the other one performs
iterations in the dual space. We prove strong convergence of both methods.
Effect of Incorporating Nanoporous Metal Phosphate Materials on the Compressive Strength of Portland Cement
Authors: Wellman Dawn M. , Parker Kent E. , Mattigod Shas V. , Fryxell Glen E.
Published: March 2008

Nanoporous metal phosphate (NP-MPO) materials are being developed for removal of contaminant oxyanions (As(OH), , and ), and cations (mercury, cadmium, and lead) from water and waste streams. Following sequestration, incorporation of metal laden NP-MPOs as a portion of cement formulation would provide an efficient and low-cost way to immobilize metal laden NP-MPOs in an easily handled waste form suitable for permanent disposal. There are no known investigations regarding the incorporation of NP-MPOs in concrete and the effects imparted on the physical and mechanical properties of concrete. Results of this investigation demonstrated that incorporating of NP-MPO materials requires additional water in the concrete formulation which decreases the compressive strength. Thus, incorporation of NP-MPOs in concrete may not serve as an efficient means for long-term disposal.
Development Considerations of AREVA NP Inc.'s Realistic LBLOCA Analysis Methodology
Authors: Martin Robert P. , O'Dell Larry D.
Published: March 2008

The AREVA NP Inc. realistic large-break loss-of-coolant-accident (LOCA) analysis methodology references the 1988 amended 10 CFR 50.46 allowing best-estimate calculations of emergency core cooling system performance. This methodology conforms to the code scaling, applicability, and uncertainty (CSAU) methodology developed by the Technical Program Group for the United States Nuclear Regulatory Commission in the late 1980s. In addition, several practical considerations were revealed with the move to a production application. This paper describes the methodology development within the CSAU framework and utility objectives, lessons learned, and insight about current LOCA issues.
Peroxisome Proliferator‐Activated Receptor‐γ Is a Potent Target for Prevention and Treatment in Human Prostate and Testicular Cancer
Authors: Matsuyama Masahide , Yoshimura Rikio
Published: March 2008

Peroxisome proliferator‐activated receptor‐γ (PPAR)‐γ is a ligand‐activated transcriptional factor belonging to steroid receptor superfamily. PPAR‐γ plays a role in both adipocyte differentiation and tumorigenesis. Up to date, PPAR‐γ is expressed in various cancer tissues, and PPAR‐γ ligand induces growth arrest of these cancer cells. In this study, we examined the expression of PPAR‐γ in prostate cancer (PC) and testicular cancer (TC) by RT‐PCR and immunohistochemistry, and we also examined the effect of PPAR‐γ ligand in these cells by MTT assay, hoechest staining, and flow cytometry. PPAR‐γ expression was significantly more extensive and intense in malignant tissues than in normal tissues. PPAR‐γ ligand induced the reduction of malignant cell viability through apoptosis. These results demonstrated that the generated PPAR‐γ in PC and TC cells might play an important role in the tumorigenesis. PPAR‐γ may become a new target in the treatment of PC and TC.
Influence of Irradiance, Flow Rate, Reactor Geometry, and Photopromoter Concentration in Mineralization Kinetics of Methane in Air and in Aqueous Solutions by Photocatalytic Membranes Immobilizing Titanium Dioxide
Authors: Bellobono Ignazio Renato , Rossi Mauro , Testino Andrea , Morazzoni Franca , Bianchi Riccardo , de Martini Giulia , Tozzi Paola Maria , Stanescu Rodica , Costache Cristina , Bobirica Liliana , Bonardi Mauro Luigi , Groppi Flavia
Published: March 2008

Photomineralization of methane in air (10.0–1000 ppm (mass/volume) of C) at 100% relative humidity (dioxygen as oxygen donor) was systematically studied at 318 ± 3 K in an annular laboratory‐scale reactor by photocatalytic membranes immobilizing titanium dioxide as a function of substrate concentration, absorbed power per unit length of membrane, reactor geometry, and concentration of a proprietary vanadium alkoxide as photopromoter. Kinetics of both substrate disappearance, to yield intermediates, and total organic carbon (TOC) disappearance, to yield carbon dioxide, were followed. At a fixed value of irradiance (0.30 W · cm−1), the mineralization experiments in gaseous phase were repeated as a function of flow rate (4–400 m3 · h−1). Moreover, at a standard flow rate of 300 m3 · h−1, the ratio between the overall reaction volume and the length of the membrane was varied, substantially by varying the volume of reservoir, from and to which circulation of gaseous stream took place.
Photomineralization of methane in aqueous solutions was also studied, in the same annular reactor and in the same conditions, but in a concentration range of 0.8–2.0 ppm of C, and by using stoichiometric hydrogen peroxide as an oxygen donor. A kinetic model was employed, from which, by a set of differential equations, four final optimised parameters, k1 and K1, k2 and K2, were calculated, which is able to fit the whole kinetic profile adequately. The influence of irradiance on k1 and k2, as well as of flow rate on K1 and K2, is rationalized. The influence of reactor geometry on k values is discussed in view of standardization procedures of photocatalytic experiments. Modeling of quantum yields, as a function of substrate concentration and irradiance, as well as of concentration of photopromoter, was carried out very satisfactorily. Kinetics of hydroxyl radicals reacting between themselves, leading to hydrogen peroxide, other than with substrate or intermediates leading to mineralization, were considered, and it is paralleled by a second competition kinetics involving superoxide radical anion.
The Weighted Fermat Triangle Problem
Authors: Shen Yujin , Tolosa Juan
Published: March 2008

We completely solve the generalized Fermat problem: given a triangle P1, P2, P3 and
three positive numbers λ1, λ2, λ3, find a point P for which the sum λ1P1P + λ2P2P + λ3P3P
is minimal. We show that the point always exists and is unique, and indicate necessary
and sufficient conditions for the point to lie inside the triangle. We provide geometric
interpretations of the conditions and briefly indicate a connection with dynamical systems.
COX‐2 Gene Promoter Polymorphism and Coronary Artery Disease in Middle‐Aged Men: The Helsinki Sudden Death Study
Authors: Huuskonen KatiH. , Kunnas TarjaA. , Tanner MinnaM. , Mikkelsson Jussi , Ilveskoski Erkki , Karhunen PekkaJ. , Nikkari SeppoT.
Published: March 2008

Cyclooxygenase (COX) catalyzes formation of prostaglandins that contribute to the inflammation in atherosclerosis. Our objective was to study whether the functional C variant of the −765G → C polymorphism in the human COX‐2 gene associates with
the severity of coronary atherosclerosis measured at the coronary
artery level. The Helsinki sudden death study autopsy material
(n = 300) comprised of Finnish men who died suddenly.
The area of atherosclerotic lesions in the coronary arteries was
quantitated, and coronary narrowing was measured. The occurrence
of myocardial infarction (MI) was assessed. Genotyping was by
restriction endonuclease analysis. Men carrying the minor C allele
had larger areas of complicated lesions (P = .024)
and a higher number of coronary arteries that had over 50%
stenosis (P = .036) compared to men representing the
common GG genotype. The COX‐2 polymorphism was not associated with
MI. Our data suggest that COX‐2 may be involved in plaque
growth.
The Gain of Performance of Optical WDM Networks
Authors: Bahleda Miroslav , Blunar Karol
Published: March 2008

We study the blocking probability and performance of single‐fiber and multifiber optical networks with wavelength division multiplexing (WDM). We extend the well‐known analytical blocking probability model by Barry and Humblet to the general model, which is proposed for both single‐fiber and multifiber network paths with any kind of wavelength conversion (no, limited, or full wavelength conversion) and for uniform and nonuniform link loads. We investigate the effect of the link load, wavelength conversion degree, and the number of wavelengths, fibers, and hops on blocking probability. We also extend the definition of the gain of wavelength conversion by Barry and Humblet to the gain of performance, which is fully general. Thanks to this definition and implementation of our model, we compare different WDM node architectures and present interesting results.
A Statistical Methodology for Determination of Safety Systems Actuation Setpoints Based on Extreme Value Statistics
Authors: Novog D. R. , Sermer P.
Published: March 2008

This paper provides a novel and robust methodology for determination of nuclear reactor trip setpoints which accounts for uncertainties in input parameters and models, as well as accounting for the variations in operating states that periodically occur. Further it demonstrates that in performing best estimate and uncertainty calculations, it is critical to consider the impact of all fuel channels and instrumentation in the integration of these uncertainties in setpoint determination. This methodology is based on the concept of a true trip setpoint, which is the reactor setpoint that would be required in an ideal situation where all key inputs and plant responses were known, such that during the accident sequence a reactor shutdown will occur which just prevents the acceptance criteria from being exceeded. Since this true value cannot be established, the uncertainties in plant simulations and plant measurements as well as operational variations which lead to time changes in the true value of initial conditions must be considered. This paper presents the general concept used to determine the actuation setpoints considering the uncertainties and changes in initial conditions, and allowing for safety systems instrumentation redundancy. The results demonstrate unique statistical behavior with respect to both fuel and instrumentation uncertainties which has not previously been investigated.
Cryptochrome and Period Proteins Are Regulated by the CLOCK/BMAL1 Gene: Crosstalk between the PPARs/RXRα‐Regulated and CLOCK/BMAL1‐Regulated Systems
Authors: Nakamura Koh-ichi , Inoue Ikuo , Takahashi Seiichiro , Komoda Tsugikazu , Katayama Shigehiro
Published: March 2008

Feeding and the circadian system regulate lipid absorption and metabolism, and the expression of enzymes involved in lipid metabolism is believed to be directly controlled by the clock system. To investigate the interaction between the lipid metabolism system and the circadian system, we analyzed the effect of a CLOCK/BMAL1 heterodimer on the transcriptional regulation of PPAR‐controlled genes through PPAR response elements (PPREs). Transcription of acyl‐CoA oxidase, cellular retinol binding protein II (CRBPII), and 3‐hydroxy‐3‐methylglutaryl coenzyme A (HMG‐CoA) synthase was altered by CLOCK/BMAL1, and transcriptional activity via PPRE by PPARs/RXRα was enhanced by CLOCK/BMAL1 and/or by PPARs ligand/activators. We also found that CLOCK/BMAL1‐mediated transcription of period (PER) and cryptochrome (CRY) was modulated by PPARα/RXRα. These results suggest that there may be crosstalk between the PPARs/RXRα‐regulated system and the CLOCK/BMAL1‐regulated system.