bluuebunny/crossref_metadata_2025 huggingface dataset:
SNAP-STABILIZING PREFIX TREE FOR PEER-TO-PEER SYSTEMS
Authors: CARON EDDY , DESPREZ FRÉDÉRIC , PETIT FRANCK , TEDESCHI CÉDRIC
Published: April 2010

Several factors still hinder the deployment of computational grids over large scale platforms. Among them, the resource discovery is one crucial issue. New approaches, based on peer-to-peer technologies, tackle this issue. Because they efficiently allow range queries, Tries (a.k.a., Prefix Trees) appear to be among promising ways in the design of distributed data structures indexing resources. Despite their lack of robustness in dynamic settings, trie-structured approaches outperform other peer-to-peer fashioned technologies by efficiently supporting range queries. Within recent trie-based approaches, the fault-tolerance is handled by preventive mechanisms, intensively using replication. However, replication can be very costly in terms of computing and storage resources and does not ensure the recovery of the system after arbitrary failures.

Self-stabilization is an efficient approach in the design of reliable solutions for dynamic systems. It ensures a system to converge to its intended behavior, regardless of its initial state, in a finite time. A snap-stabilizing algorithm guarantees that it always behaves according to its specification, once the protocol is launched. In this paper, we provide the first snap-stabilizing protocol for trie construction. We design particular tries called Proper Greatest Common Prefix (PGCP) Tree. The proposed algorithm arranges the n label values stored in the tree, in average, in O(h + h′) rounds, where h and h′ are the initial and final heights of the tree, respectively. In the worst case, the algorithm requires an O(n) extra space on each node, O(n) rounds and O(n2) actions. However, simulations allow to state that this worst case is far from being reached and to confirm the average complexities, showing the practical efficiency of this protocol.
ON THE INPUT ACCEPTANCE OF TRANSACTIONAL MEMORY
Authors: Gramoli Vincent , Harmanci Derin , Felber Pascal
Published: April 2010

We present the Input Acceptance of Transactional Memory (TM). Despite the large interest for performance of TMs, no existing research work has investigated the impact of solving a conflict that does not need to be solved. Traditional solutions for a TM to be correct is to delay or abort a transaction as soon as it presents a risk to violate consistency. Both alternatives are costly and should be avoided if consistency is actually preserved. To address this problem, we introduce the input acceptance of a TM as its ability to commit transactions, we upper-bound the input acceptance of existing TMs and propose a new TM with higher input acceptance.
ON THE COMPILATION OF A LANGUAGE FOR GENERAL CONCURRENT TARGET ARCHITECTURES
Authors: BERNARD THOMAS A.M. , GRELCK CLEMENS , JESSHOPE CHRIS R.
Published: April 2010

The challenge of programming many-core architectures efficiently and effectively requires models and methods to co-design chip architectures and their software tool chain, using an approach that is both vertical and general. In this paper, we present compilation schemes for a general model of concurrency captured in a parallel language designed for system-level programming and as a target for higher level compilers. We also expose the challenges of integrating these transformation rules into a sequential-oriented compiler. Moreover, we discuss resource mapping inherent to those challenges. Our aim has been to reuse as much of the existing sequential compiler technology as possible in order to harness decades of prior research in compiling sequential languages.
AN IMPROVED BACKGROUND SUBTRACTION ALGORITHM AND CONCURRENT IMPLEMENTATIONS
Authors: SILVEIRA CÉSAR L. B. , CAVALHEIRO GERSON GERALDO H. , JUNG CLÁUDIO R. , JACQUES JULIO C. S. , MUSSE SORAIA R.
Published: April 2010

This paper proposes a concurrent implementation of a background subtraction algorithm suitable for monochromatic video sequences. In the training period, a set of frames is used to determine an estimate of the scene background, as well as background noise. In the test period, each new frame of the video sequence is compared to the background model, and foreground objects are obtained taking into account the background noise estimate. Shadows and highlights are also detected and removed. Concurrent programming tools and techniques, such as multithreading, are used to implement a concurrent solution for this problem, and combined with other optimization tools (such as destination word accumulation for morphological operators and the use of lookup tables for shadow detection/removal) to achieve the highest frame rate possible. Experimental results comprise a comparison of the performance including progressively each optimization tool, and they show that the fully optimized algorithm is much faster than a naive sequential implementation. Also, experiments performed on two-way processor and on dual-core processor computers indicate that the proposed algorithm is suited for the recent multi-core technology.
OPTIMAL SUBCUBE EMBEDDABILITY IN HYPERCUBES WITH ADDITIONAL DIMENSIONS
Authors: YASIM SHAMEEMA , LATIFI SHAHRAM
Published: April 2010

Subcube embeddability of the hypercube can be enhanced by introducing an additional dimension. A set of new dimensions, characterized by the Hamming distance between the pairs of nodes it connects, is introduced using a measure defined as the magnitude of a dimension. An enumeration of subcubes of various size is presented for a dimension parameterized by its magnitude. It is shown that the maximum number of subcubes for a Qn can only be attained when the magnitude of dimension is n-1 or n. It is further shown that the latter two dimensions can optimally increase the number of subcubes among all possible choices.
SDP RELAXATIONS FOR QUADRATIC OPTIMIZATION PROBLEMS DERIVED FROM POLYNOMIAL OPTIMIZATION PROBLEMS
Authors: MEVISSEN MARTIN , KOJIMA MASAKAZU
Published: April 2010

Based on the convergent sequence of SDP relaxations for a multivariate polynomial optimization problem (POP) by Lasserre (2006), Waki et al. (2006) constructed a sequence of sparse SDP relaxations to solve sparse POPs efficiently. Nevertheless, the size of the sparse SDP relaxation is the major obstacle in order to solve POPs of higher degree. This paper proposes an approach to transform general POPs to quadratic optimization problems (QOPs), which allows to reduce the size of the SDP relaxation substantially. We introduce different heuristics resulting in equivalent QOPs and show how sparsity of a POP is maintained under the transformation procedure. As the most important issue, we discuss how to increase the quality of the SDP relaxation for a QOP. Moreover, we increase the accuracy of the solution of the SDP relaxation by applying additional local optimization techniques. Finally, we demonstrate the high potential of this approach through numerical results for large scale POPs of higher degree.
METRIC-PRESERVING REDUCTION OF EARTH MOVER'S DISTANCE
Authors: TAKANO YUICHI , YAMAMOTO YOSHITSUGU
Published: April 2010

Earth mover's distance (EMD for short) is a perceptually meaningful dissimilarity measure between histograms. The computation of EMD reduces to a network flow optimization problem; however, it lays a heavy computational burden when the number of locations of histograms is large. In this paper, we address an efficient formulation for computing the exact EMD value. We prove that the EMD problem reduces to a problem with half the number of constraints regardless of the ground distance. We then propose a further reduced formula in which the number of variables is reduced from O(m2) to O(m) for histograms with m locations when the ground distance is derived from a graph with a homogeneous neighborhood structure. Specifically, EMD problems with L1, L∞ and D-norm ground distances can be reduced in this manner. Some experiments show that the reduction helps compute the EMD efficiently.
A CONVEX APPROXIMATION METHOD FOR LARGE SCALE LINEAR INEQUALITY CONSTRAINED MINIMIZATION
Authors: WANG HAI-JUN , NI QIN
Published: April 2010

A new method of moving asymptotes for large scale minimization subject to linear inequality constraints is discussed in this paper. In each step of the iterative process, a descend direction is obtained by solving a convex separable subproblem with dual technique. The new rules for controlling the asymptotes parameters are designed by the trust region radius and some approximation properties such that the global convergence of the new method are obtained. The numerical results show that the new method may be capable of processing some large scale problems.
EVALUATION OF THE ARROWS METHOD FOR CLASSIFICATION OF DATA
Authors: LU LANTING , CURRIE CHRISTINE S. M.
Published: April 2010

We evaluate the Arrows Classification Method (ACM) for grouping objects based on the similarity of their data. This is a new method, which aims to achieve a balance between the conflicting objectives of maximizing internal cohesion and external isolation in the output groups. The method is widely applicable, especially in simulation input and output modelling, and has previously been used for grouping machines on an assembly line, based on data on time-to-repair; and hospital procedures, based on length-of-stay data. The similarity of the data from a pair of objects is measured using the two-sample Cramér-von-Mises goodness of fit statistic, with bootstrapping employed to find the significance or p-value of the calculated statistic. The p-values coming from the paired comparisons serve as inputs to the ACM, and allow the objects to be classified such that no pair of objects that are grouped together have significantly different data. In this article, we give the technical details of the method and evaluate its use through testing with specially generated samples. We will also demonstrate its practical application with two real examples.
AHARONOV–BOHM EFFECT ON QUANTUM TRANSPORT IN SINGLE-WALLED CARBON NANOTUBE INTERFEROMETERS
Authors: HAN MEI , ZHANG YONG
Published: April 2010

The quantum conductance of the electron interferometers composed of the armchair and metallic zigzag single-walled carbon nanotubes (SWNTs) in an axial magnetic field lower than 100 T has been studied by using the tight-binding approximation and Landauer–Buttiker formula. Quantum conductance oscillation as a function of gate voltage due to Fabry–Perot like electron interference was found. The analytical expressions of the rapid and slow conductance oscillation periods for the armchair SWNTs have been derived. It is shown that they depend on the magnetic field, gate voltage, and tube length. For the case of the metallic zigzag SWNTs, except rapid conductance oscillation, slow conductance oscillation was also found, which should not exist without the axial magnetic field.
LONG-LIVED ENTANGLEMENT OF THREE-ATOM IN AN OPTICAL CAVITY WITH PHASE DECOHERENCE
Authors: ZHANG JIAN-SONG , CHEN AI-XI
Published: April 2010

We investigate the entanglement dynamics in a quantum system consisting of three two-level atoms resonantly coupled to a single mode cavity in the presence of phase decoherence. With the help of the dynamical algebraic method, we obtain an analytical solution of the present system. The influence of phase decoherence on the entanglement of the system is studied. We find that the entanglement between the cavity field and any atom will be destroyed completely by phase decoherence as the system evolves. However, there is long-lived entanglement (or stationary state entanglement) of arbitrary two atoms, that is, the entanglement of atoms is more robust against phase decoherence than that of the atom-field system.
ON THE POSSIBILITY OF SUPPRESSING DIFFRACTION OSCILLATIONS NEAR THE PHOTONIC BAND GAP
Authors: GEVORGYAN A. H.
Published: April 2010

Oblique light propagation through a chiral photonic crystal (PC) layer with gradient parameters of modulation is considered. The problem is solved by Ambartsumian's layer addition modified method. It is shown that suppressing of diffraction oscillations near the photonic band gap (PBG) is possible at certain conditions. Thus, at certain conditions, the spectra for the finite PC layer is the same as that for the half space.
EXPERIMENTAL REALIZATION OF A RECONFIGURABLE THREE INPUT, ONE OUTPUT LOGIC FUNCTION BASED ON A CHAOTIC CIRCUIT
Authors: POURSHAGHAGHI HAMID REZA , AHMADI REZA , JAHED-MOTLAGH MOHAMMAD REZA , KIA BEHNAM
Published: April 2010

This paper addresses and reports the construction of a reconfigurable logic block that can morph between all three input, one output logic functions based on chaos computing theory. The logic block is constructed based on a discrete chaotic circuit and can emulate all three input, one output logic functions. We have derived instruction set table of this logic block from the block that can be used as a look up table to generate any special three input, one output logic function. Additionally, sensitivity of constructed logic block to noise is investigated and a method for enhancing robustness of block with respect to the environment noise is proposed and implemented. This chaotic block offers inventive approaches for constructing higher order logic functions.
HYPERSTRUCTURES, A NEW APPROACH TO COMPLEX SYSTEMS
Authors: CRIADO R. , ROMANCE M. , VELA-PÉREZ M.
Published: April 2010

We define a new concept, a hyperstructure, which is related to networks and hypernetworks and allows us to represent real problems. We also define the efficiency of this hyperstructure and we apply it to an example.
THIRD ORDER LOOPS OF CONTACTS IN A GRANULAR FORCE NETWORK
Authors: ARÉVALO ROBERTO , ZURIGUEL IKER , TREVIJANO SERGIO ARDANZA , MAZA DIEGO
Published: April 2010

The existence of small order loops of contacts is presented as an intrinsic characteristic of force granular networks. Based on molecular dynamics simulations, it is proposed that the presence of these small order loops — and in particular third order loops of contacts — is important to understand the transition from fluid-like to solid-like behavior of granular packings. In addition, we show a close relationship between the development of third order loops and the small forces of the granular packing in the sense that almost all third order loops allocate a force component smaller than the average.
SWITCHER-RANDOM-WALKS: A COGNITIVE-INSPIRED MECHANISM FOR NETWORK EXPLORATION
Authors: GOÑI JOAQUÍN , MARTINCORENA IÑIGO , COROMINAS-MURTRA BERNAT , ARRONDO GONZALO , ARDANZA-TREVIJANO SERGIO , VILLOSLADA PABLO
Published: April 2010

Semantic memory is the subsystem of human memory that stores knowledge of concepts or meanings, as opposed to life specific experiences. The organization of concepts within semantic memory can be understood as a semantic network, where the concepts (nodes) are associated (linked) to others depending on perceptions, similarities, etc. Lexical access is the complementary part of this system and allows the retrieval of such organized knowledge. While conceptual information is stored under certain underlying organization (and thus gives rise to a specific topology), it is crucial to have an accurate access to any of the information units, e.g. the concepts, for efficiently retrieving semantic information for real-time need. An example of an information retrieval process occurs in verbal fluency tasks, and it is known to involve two different mechanisms: "clustering", or generating words within a subcategory, and, when a subcategory is exhausted, "switching" to a new subcategory. We extended this approach to random-walking on a network (clustering) in combination to jumping (switching) to any node with certain probability and derived its analytical expression based on Markov chains. Results show that this dual mechanism contributes to optimize the exploration of different network models in terms of the mean first passage time. Additionally, this cognitive inspired dual mechanism opens a new framework to better understand and evaluate exploration, propagation and transport phenomena in other complex systems where switching-like phenomena are feasible.
ROBUSTNESS OF TRANSCRIPTIONAL REGULATION IN YEAST-LIKE MODEL BOOLEAN NETWORKS
Authors: TUĞRUL MURAT , KABAKÇIOĞLU ALKAN
Published: April 2010

We investigate the dynamical properties of the transcriptional regulation of gene expression in the yeast Saccharomyces Cerevisiae within the framework of a synchronously and deterministically updated Boolean network model. With a dynamically determinant subnetwork, we explore the robustness of transcriptional regulation as a function of the type of Boolean functions used in the model that mimic the influence of regulating agents on the transcription level of a gene. We compare the results obtained for the actual yeast network with those from two different model networks, one with similar in-degree distribution as the yeast and otherwise random, and another due to Balcan et al., where the global topology of the yeast network is reproduced faithfully. We, surprisingly, find that the first set of model networks better reproduce the results found with the actual yeast network, even though the Balcan et al. model networks are structurally more similar to that of yeast.
UNIQUELY 2-DIVISIBLE BOL LOOPS
Authors: FOGUEL TUVAL , KINYON MICHAEL
Published: April 2010

Although any finite Bol loop of odd prime exponent is solvable, we show there exist such Bol loops with trivial center. We also construct finitely generated, infinite, simple Bruck loops of odd prime exponent for sufficiently large primes. This shows that the Burnside problem for Bruck loops has a negative answer.
DERIVATIONS OF THE LOCALLY NILPOTENT MATRIX RINGS
Authors: LEVCHUK VLADIMIR M. , RADCHENKO OKSANA V.
Published: April 2010

Derivations of the ring of all finitary niltriangular matrices over an arbitrary associative ring with identity for any chain of matrix indices are described. Every Lie or Jordan derivation is a derivation of this ring modulo third hypercenter.
AN ALGEBRA GENERATED BY TWO SETS OF MUTUALLY ORTHOGONAL IDEMPOTENTS
Authors: ITO TATSURO , TERWILLIGER PAUL
Published: April 2010

For a field 𝔽 and an integer d ≥ 1, we consider the universal associative 𝔽-algebra A generated by two sets of d + 1 mutually orthogonal idempotents. We display four bases for the 𝔽-vector space A that we find attractive. We determine how these bases are related to each other. We describe how the multiplication in A looks with respect to our bases. Using our bases we obtain an infinite nested sequence of two-sided ideals for A. Using our bases we obtain an infinite exact sequence involving a certain 𝔽-linear map ∂: A → A. We obtain several results concerning the kernel of ∂; for instance this kernel is a subalgebra of A that is free of rank d.
Airport Safety
Authors: Kabay M. E.
Published: April 2010

The current implementation of do-not-fly lists and the use of documents to authenticate passenger identity won't necessarily improve airport security.
Mihai Nadin on Anticipatory Systems
Authors: Staff Ubiquity
Published: April 2010

What is the difference between a falling stone and a falling cat? Mihai Nadin, who directs the newly established Institute for Research in Anticipatory Systems at the University of Texas at Dallas, holds a Ph.D. degree in aesthetics from the University of Bucharest and a post-doctoral degree in philosophy, logic and theory of science from Ludwig Maximilian University in Munich, West Germany. He earned an M.S. degree in electronics and computer science from the Polytechnic Institute of Bucharest and an M.A. degree in philosophy from the University of Bucharest. He has authored 23 books, including "The Civilization of Illiteracy," "Mind: Anticipation and Chaos," and "Anticipation: The End is Where We Start From."
IT job outsourcing
Authors: Ghimire Bhumika
Published: April 2010

Bhumika Ghimire, who is from Nepal, is a graduate of Schiller University, where he studied IT Management and where outsourcing was his special field of interest. Here, he asks, "How do we define outsourcing?"
What Can Be Taught: Part I
Authors: Schank Roger C.
Published: April 2010

Not everything we would like to teach can be taught. Similarly, not everything we would like to learn can be learned, especially if we are taking the wrong approach to learning. In a previous column, I discussed things that can't be taught. Here I discuss what can be taught. In this two-part article, I discuss the kinds of thing we can learn. I consider how we can best approach learning by listing 16 types of learning. There may be more, but those 16 will at least cover enough ground to describe how human learning looks. The types of learning are divided into four groups: 1) conscious processes, which I will cover here in Part I, 2) subconscious processes, 3) analytic processes, and 4) mixed processes (nos. 2, 3, and 4 are covered in the forthcoming Part II).
Work and Learning
Authors: Barr Tom
Published: April 2010

The days of orchestrating corporate learning through special "events," such as classroom training and seminars, have given way to learning on-the-job. Indeed, working and learning are becoming so tightly integrated that it's often difficult to differentiate between them. Motorola University, and indeed corporate universities and training departments in general, have undergone or are undergoing quite a transition in the wake of Web 2.0 technologies. System work tools and learning tools are becoming synonymous.
Book Review of Make Money Teaching Online
Authors: Welch Mark
Published: April 2010

Mark Welch reviews the book Make Money Teaching Online: How to Land Your First Academic Job, Build Credibility, and Earn a Six-Figure Salary by Dr. Danielle Babb and Dr. Jim Mirabella, published by Wiley Press (2007).
lrnchat
Authors: Ferguson Dave , Pettit Christy
Published: April 2010

#lrnchat (or "Learn Chat") is an open online meeting about learning that takes place weekly on Twitter. eLearn Magazine asked two recent participants to share their thoughts about #lrnchat, describe how it works, and explain the benefits of participating. According to Dave Ferguson, Twitter chats are no different than the business conference cocktail houra prime time for networking. And Christy Pettit has explored business opportunities thanks to her involvement in #lrnchat. So instead of must-see TV, tune into #lrnchat on Thursday nights, 8:30 p.m. to 10:00 p.m. Eastern time.
Publish or Perish
Authors: Quinn Clark
Published: April 2010

It's not news that we're experiencing increasing change. The quantity of information available is growing astronomically, new offerings are increasingly quick to be copied, businesses are under pressure to do more with less, and the internet is a disruptive force, threatening all manner of content industries. Organizations have to become more nimble, more agile. Optimal execution is only the cost of entry, and organizations have to be tapping into continual innovation. Publishers are not exempt from this. There are major pressures coming in a variety of guises. Yet, surprisingly, we're seeing little innovation in products, services, or business models.
The State of Distance Education in Saudi Arabia
Authors: Al-Khalifa Hend Suliman
Published: April 2010

In this exclusive report, Hend Suliman Al-Khalifa of King Saud University, Riyadh, explains how Saudi Arabia has begun adopting distance education as part of its educational and development strategies. Saudi Arabia has been slower than many nations to move into distance education. Bachelor degree programs have only been offered through traditional universities' distance education programs for about a decade, and policies for single-mode, distance, and virtual tertiary institutions are still under development for approval by the Ministry of Higher Education. Some public universities, such as King Abdulaziz University and Al-Imam Mohammad ibn Saud Islamic University, are dual-mode, while single-mode distance education is offered by the Arab Open University. Distance education is primarily applied where gender segregation is required in tertiary education, where male lecturers are only authorized to teach female students by means of closed-circuit television, one-way video and two-way audio and broadcast.
Teaching Teachers to Use Blended Learning
Authors: Knipe Sally , Edwards Miriam
Published: April 2010

Blended learning focuses on what students do and how teachers support the learning process. At Charles Sturt University, Australia, first-year undergraduate preservice teachers use blended learning in their own education as they become more familiar with the physical, emotional, social, and cultural aspects of the early adolescents they will soon teach.
Enhancing K-12 Academic Integrity
Authors: Barnard Doug , Hutchins Terry
Published: April 2010

Cheating has dramatically increased, at all levels, in the past few years. How cheating and false identity issues are addressed by individual online education programs will determine the collective futures of everyone working in e-learning.
Book Review: 'Rethinking Education in the Age of Technology'
Authors: McWilliams Jenna
Published: April 2010

"Our fear is that social cohesion and equity inherent in the promise of public schooling will be undermined by (the Knowledge Revolution)." Allan Collins and Richard Halverson make this statement early on in their fascinating, but ultimately somewhat short-sighted book, Rethinking Education in the Age of Technology: The Digital Revolution and Schooling in America (2008). This fear comprises the lynchpin of the authors' thesis: that new media technologies are changing how, where, and why learning happens as well as what role schools play in that learning. The results of this shift, according to the authors, aren't good.
U.K. Study Finds 'People Problems' in e-Learning
Authors: Little Bob
Published: April 2010

Attitudes in Britain toward the use of learning technologies are changing, which has implications for U.S.-based firms that want to use e-learning in its U.K. offices. A recently published benchmarking study by Towards Maturity showed that 64 percent of organizations in the U.K. are increasing their learning technologies budgets in 2009 for the following top three reasons: 1) strengthening on-boarding training, 2) improving the quality of learning, and 3) developing a better qualified workforce.
Book Review of 'Disrupting Class' by Clayton M. Christensen, Michael B. Horn, and Curtis W. Johnson
Authors: Sener John
Published: April 2010

It seems like everyone these days wants to "fix" American education -- including the business community, which has produced a steady stream of books offering business-oriented solutions to the education "problem." 'Disrupting Class,' by Christensen, Horn, and Johnson, was 2008's star solutions manual, receiving much attention and acclaim from not only the business community, but also education leaders, as evidenced by favorable reviews and testimonials found on a web site related to the book. But is the book suitable for the unique structure of online education?
e-Learning Optimism
Authors: Little Bob
Published: April 2010

The e-learning sector is "flowering" in 2009 despite the recession, or so says a recent report on e-learning in the U.K.
An Alternative Way to Assess the ROI of e-Learning in Training
Authors: Lambe Patrick
Published: April 2010

In Part I of this article, Patrick Lambe provided a brief background on the economics of e-learning. Here in Part II, he looks at some of the most common ways that organizations deploy e-learning to support their strategic objectives, and shows how measurement of viability and impact can be approached within those situations.
Learning is Still the Same
Authors: Schank Roger C.
Published: April 2010

Learning is learning and technology is technology. The two are related if and only if the technology makes it possible to learn something that can be learned in no other way. E-learning is quite often a watered down version of school. Whether it relies on computers, mobile devices, or any other technology the question is, "Is it any better than what it replaced?"
Mobilizing and Globalizing with Online Education
Authors: Kanwar Anju
Published: April 2010

Whatever the times, education is an important vehicle to rise above certain of life's inequities. While many countries, including so-called third world nations, have slowly been building their educational systems, Americadespite its policies, programs, and good intenthas paid mere lip service to the realization of its educational goals. Consequently, education in many states in America is witnessing a breakdown.
Predictors of Success for Adult Online Learners: A Review of the Literature
Authors: Gruenbaum Elizabeth A.
Published: April 2010

What are the predictors of adult students' success in online learning environments? Is there a difference in undergraduate versus graduate online learners and their motivations? Does age play a factor? Do the course's characteristics have an impact on performance and learner satisfaction? What are the implications of these findings for online instructors, and how could that affect their practices and approaches to retaining students in the future?
Unresolved Obstacles to the Credibility of Online Degrees
Authors: Howard Craig
Published: April 2010

"This is too much work for an online class." For the last two years I've heard that comment repeatedly from students. I've been teaching since 1995, but about two years ago, I started teaching online. The "too much work" these students refer to is actually the exact same amount of work as in the face-to-face equivalent course. So what's behind what these students are saying?
21st Century Skills
Authors: Cogan-Drew Dan
Published: April 2010

If you've been following public discourse in education over the last couple of years, you have likely witnessed the emergence of a new, ubiquitous catch phrase: "21st century skills." What is still lacking in the landscape of 21st century education, however, are examples of 21st century student work.
Teaching Diagnosis
Authors: Schank Roger C.
Published: April 2010

What do people need to learn? Every curriculum committee and every training organization has at one time or another convened a committee to answer this question. Their answers are always given in terms of subjects: "more math," "telecommunication," "risk management," "company policies." But subject matter is far less important in learning than you think.
E-Learning and ICT Integration in Colleges and Universities in Saudi Arabia
Authors: Al-Khalifa Hend Suliman
Published: April 2010

In 2002, GOTEVOT, the government authority responsible for the Kingdom of Saudi Arabia's technical education and vocational training, established the E-Learning Training and Resources Centre. The Centre provides an e-library of more than 50,000 books and 3,000 training programs for lifelong learning and community services with electronic training portfolios. The organization publishes its technical and vocational courses in both Arabic and English on the web.
Review: 'The E-Learning Handbook: Past Promises, Present Challenges,' by Saul Carliner and Patti Shank
Authors: Kapp Karl M.
Published: April 2010

The E-Learning Handbook covers the good, the bad, and the ugly of e-learning and provides a glimpse into the industry's future. The Handbook provides a broad look at the past expectations of e-learning and then follows up those expectations with myriad instructions, ideas, and concepts to carry the industry forward.
Career Tracks for Online Educators
Authors: Welch Mark , Robertson Bob , Adamson Darren
Published: April 2010

When the best online instructors can see a viable and attractive career track for themselves, they are more likely to be satisfied and more productive with the institution and their students. To increase instructor retention in online education, we propose four separate but interchangeable career tracks that instructors can move between.
eLearning Tools for English Composition
Authors: Bjorklund Keri
Published: April 2010

One of the hurdles to getting faculty and students to use technology in education is introducing them to the right tools for their needs. A number of technologies are indispensible for any online course, but some apply specifically to teaching composition. Here are 30 that every English instructor should explore.
Leakage-saving opportunities in mesh-based massive multi-core architectures
Authors: Musoll Enric
Published: April 2010

When processing multi-threaded workloads requiring significant inter-thread communication, opportunities to reduce power consumption arise due to the large latencies in obtaining data from the threads running on remote cores and the lack of architectural resources implemented in the simple cores to cover these latencies.

In this work we propose to use the drowsy mode technique to save leakage power on the cores and leverage the mesh-based communication fabric to hide the wake-up latency of the core blocks. We have observed a potential for reducing the overall power of around 70% in a generic homogeneous 256-core tile-based multi-core architecture.
Scalability of relaxed consistency models in NoC based multicore architectures
Authors: Naeem Abdul , Chen Xiaowen , Lu Zhonghai , Jantsch Axel
Published: April 2010

This paper studies realization of relaxed memory consistency models in the network-on-chip based distributed shared memory (DSM) multi-core systems. Within DSM systems, memory consistency is a critical issue since it affects not only the performance but also the correctness of programs. We investigate the scalability of the relaxed consistency models (weak, release consistency) implemented by using transaction counters. Our experimental results compare the average and maximum code, synchronization and data latencies of the two consistency models for various network sizes with regular mesh topologies. The observed latencies rise for both the consistency models as the network size grows. However, the scaling behaviors are different. With the release consistency model these latencies grow significantly slower than with the weak consistency due to better optimization potential by means of overlapping, reordering and program order relaxations. The release consistency improves the performance by 15.6% and 26.5% on average in the code and consistency latencies over the weak consistency model for the specific application, as the system grows from single core to 64 cores. The latency of data transactions grows 2.2 times faster on the average with a weak consistency model than with a release consistency model when the system scales from single core to 64 core
Reliability and path length analysis of irregular fault tolerant multistage interconnection network
Authors: Sharma Sandeep , Kahlon K. S. , Bansal P. K.
Published: April 2010

In this paper reliability and path length analysis of irregular Multistage Interconnection Networks have been presented. We have examined FT(Four Tree)[8],MFT(Modified Four Tree)[2],NFT(New Four Tree)[4],IFT(improved Four Tree)[5],IASN(Irregular Augmented Shuffle)[14] and IIASN(Improved Irregular Augmented Shuffle)[3] networks in which the number of switches in each stage are different in numbers and also have express links[11]. Using upper and lower bounds[7][13][15] for larger networks, the reliability[9] in terms of mean time to failure of all these networks are evaluated and compared with each other. Each source is connected to destination with one or multiple paths with varying path lengths in a network. The path length analysis of all these networks is also analyzed in this paper. A path length[8] algorithm for IIASN network is also propose
Pitfalls for testbed evaluations of internet systems
Authors: Choffnes David R. , Bustamante Fabian E.
Published: April 2010

Today's open platforms for network measurement and distributed system research, which we collectively refer to as testbeds in this article, provide opportunities for controllable experimentation and evaluations of systems at the scale of hundreds or thousands of hosts. In this article, we identify several issues with extending results from such platforms to Internet wide perspectives. Specifically, we try to quantify the level of inaccuracy and incompleteness of testbed results when applied to the context of a large-scale peer-to-peer (P2P) system. Based on our results, we emphasize the importance of measurements in the appropriate environment when evaluating Internet-scale systems.
3-Hydroxymethyl coenzyme A reductase inhibition attenuates spontaneous smooth muscle tone via RhoA/ROCK pathway regulated by RhoA prenylation
Authors: Rattan Satish
Published: April 2010

RhoA prenylation may play an important step in the translocation of RhoA in the basal internal anal sphincter (IAS) smooth muscle tone. Statins inhibit downstream posttranslational RhoA prenylation by 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibition (HMGCRI). The role of statins in relation to RhoA prenylation in the pathophysiology of the spontaneously tonic smooth muscle has not been investigated. In the present studies, we determined the effect of classical HMGCRI simvastatin on the basal IAS tone and RhoA prenylation and in the levels of RhoA/Rho kinase (ROCK) in the cytosolic vs. membrane fractions of the smooth muscle. Simvastatin produced concentration-dependent decrease in the IAS tone (via direct actions at the smooth muscle cells). The decrease in the IAS tone by simvastatin was associated with the decrease in the prenylation of RhoA, as well as RhoA/ROCK in the membrane fractions of the IAS, in the basal state. The inhibitory effects of the HMGCRI were completely reversible by geranylgeranyltransferase substrate geranylgeranyl pyrophosphate. Relaxation of the IAS smooth muscle via HMGCRI simvastatin is mediated via the downstream decrease in the levels of RhoA prenylation and ROCK activity. Studies support the concept that RhoA prenylation leading to RhoA/ROCK translocation followed by activation is important for the basal tone in the IAS. Data suggest that the role of HMG-CoA reductase may go beyond cholesterol biosynthesis, such as the regulation of the smooth muscle tone. The studies have important implications in the pathophysiological mechanisms and in the novel therapeutic approaches for anorectal motility disorders.
Carbon monoxide reverses diabetic gastroparesis in NOD mice
Authors: Kashyap Purna C. , Choi Kyoung Moo , Dutta Nirjhar , Linden David R. , Szurszewski Joseph H. , Gibbons Simon J. , Farrugia Gianrico
Published: April 2010

Diabetic gastroparesis is associated with increased oxidative stress attributable to loss of upregulation of heme oxygenase-1 (HO1), with resultant damage to interstitial cells of Cajal and delayed gastric emptying. These changes can be reversed by induction of HO1. HO1 catalyzes the breakdown of heme into iron, biliverdin and, carbon monoxide (CO). The aim of this study was to determine whether inhalation of CO can mimic the protective effects of HO1. Nonobese diabetic (NOD) mice with delayed gastric emptying were treated with CO inhalation. Serum malondialdehyde was measured as a marker of oxidative stress. Gastric emptying of solids was measured using a [13C]octanoic acid breath test. Kit expression levels were determined in immunoblots of protein extracted from the external muscle layers of the gastric body and antrum. The effect of CO on oxidative stress and gastric emptying was also determined in the presence of HO activity inhibitor chromium mesoporphyrin. CO inhalation reduced oxidative stress, restored Kit expression and reversed delayed gastric emptying in diabetic NOD mice with delayed gastric emptying. CO inhalation maintained this effect in the presence of the HO activity inhibitor, chromium mesoporphyrin, also resulting in restoration of the delay in gastric emptying. CO inhalation mimics the protective effect of upregulation of HO1 and decreased oxidative stress, increased Kit expression, and restored delay in gastric emptying. This effect of CO was independent of HO activity, suggesting that its effects were downstream of HO1. CO represents a potential therapeutic option for treatment of diabetic gastroparesis.
Identification of CD44 as a senescence-induced cell adhesion gene responsible for the enhanced monocyte recruitment to senescent endothelial cells
Authors: Mun Gyeong In , Boo Yong Chool
Published: April 2010

The mechanism that is responsible for progression of atherosclerosis seen with increasing age remains controversial. This issue was addressed in the present study, by searching for genes that are uniquely expressed in senescent endothelial cells and functionally involved in inflammatory leukocyte adhesion recognized as a critical step in the initiation of atherogenesis. Senescent human umbilical vein endothelial cells (HUVECs) prepared by continuous subculturing in vitro showed higher binding affinity for monocytes (THP-1 cells, human acute monocytic leukemia cell line) compared with young cells. Gene expression profiles between young and senescent endothelial cells were compared by the cDNA microarray method, and CD44 was identified as one of the “senescence-induced cell adhesion genes” whose expression was upregulated in senescent cells and whose gene ontology annotation indicated their role in cell adhesion. The enhanced gene expression of CD44 in senescent endothelial cells was verified both at the mRNA and protein levels. Adhesion of monocytes to senescent endothelial cells was significantly reduced following pretreatment of endothelial cells with the CD44 antibody or small-interfering RNA, thus reinforcing the critical role of CD44 in the inflammatory event. Exogenous expression of CD44 in young HUVECs and in human aortic endothelial cells led to an increase in monocyte adhesion. CD44 expression levels in the rat aorta endothelium were found to increase in an age-dependent manner, as determined by immunohistochemistry and Western blotting. CD44 and other senescence-induced cell adhesion genes identified in this study may provide the novel targets for the prevention of inflammatory leukocyte adhesion leading to the development atherosclerosis.
Interferons modulate mitogen-induced protein synthesis in airway smooth muscle
Authors: Goncharova Elena A. , Lim Poay N. , Chisolm Amelia , Fogle Homer W. , Taylor Jerome H. , Goncharov Dmitry A. , Eszterhas Andrew , Panettieri Reynold A. , Krymskaya Vera P.
Published: April 2010

Severe asthma is characterized by increased airway smooth muscle (ASM) mass due, in part, to ASM cell growth and contractile protein expression associated with increased protein synthesis. Little is known regarding the combined effects of mitogens and interferons on ASM cytosolic protein synthesis. We demonstrate that human ASM mitogens including PDGF, EGF, and thrombin stimulate protein synthesis. Surprisingly, pleiotropic cytokines IFN-β and IFN-γ, which inhibit ASM proliferation, also increased cytosolic protein content in ASM cells. Thus IFN-β alone significantly increased protein synthesis by 1.62 ± 0.09-fold that was further enhanced by EGF to 2.52 ± 0.17-fold. IFN-γ alone also stimulated protein synthesis by 1.91 ± 0.15-fold; treatment of cells with PDGF, EGF, and thrombin in the presence of IFN-γ stimulated protein synthesis by 2.24 ± 0.3-, 1.25 ± 0.17-, and 2.67 ± 0.34-fold, respectively, compared with growth factors alone. The mammalian target of rapamycin (mTOR)/S6 kinase 1 (S6K1) inhibition with rapamycin inhibited IFN- and EGF-induced protein synthesis, suggesting that IFN-induced protein synthesis is modulated by mTOR/S6K1 activation. Furthermore, overexpression of tumor suppressor protein tuberous sclerosis complex 2 (TSC2), which is an upstream negative regulator of mTOR/S6K1 signaling, also inhibited mitogen-induced protein synthesis in ASM cells. IFN-β and IFN-γ stimulated miR143/145 microRNA expression and increased SM α-actin accumulation but had little effect on ASM cell size. In contrast, EGF increased ASM cell size but had little effect on miR143/145 expression. Our data demonstrate that both IFNs and mitogens stimulate protein synthesis but have differential effects on cell size and contractile protein expression and suggest that combined effects of IFNs and mitogens may contribute to ASM cell growth, contractile protein expression, and ASM remodeling in asthma.
Epigenetics and environment: a complex relationship
Authors: Aguilera Oscar , Fernández Agustín F. , Muñoz Alberto , Fraga Mario F.
Published: April 2010

The epigenomes of higher organisms constantly change over time. Many of these epigenetic changes are necessary to direct normal cellular development and differentiation in the developing organism. However, developmental abnormalities may occur in response to inappropriate epigenetic signaling that occurs secondarily to still poorly understood causes. In addition to genetic and stochastic influences on epigenetic processes, epigenetic variation can arise as a consequence of environmental factors. Here we review the effects of such environmental factors on the epigenomes of higher organisms. We discuss the possible impact of epigenetic changes on physiological and pathophysiological processes, depending in part on whether these changes occur during embryonic development or adulthood.
Thrombin and exercise similarly influence expression of cell cycle genes in cultured putative endothelial progenitor cells
Authors: Lockard Michael M. , Witkowski Sarah , Jenkins Nathan T. , Spangenburg Espen E. , Obisesan Thomas O. , Hagberg James M.
Published: April 2010

Acute exercise and exercise training may influence putative endothelial progenitor cell (EPC) number and colony forming units (CFU-ECs), although the mechanisms remain unclear. This study examined the effects of in vitro thrombin supplementation and acute exercise on CFU-EC gene expression, associated with cellular proliferation and differentiation. The effect of habitual physical activity was evaluated through analysis of EPCs from chronically high- and low-active men. Participants were healthy high- and low-active men ( n = 23), aged 55–80 yr. Circulating CD34+/VEGFR2+ number, CFU-ECs, plasma prothrombin fragment (F1+2), and thrombin-antithrombin III were measured at rest and after 30 min of exercise. Gene expression of cyclin A2, cyclin D1, p27, VE-cadherin, and VEGFR2 was assessed in postexercise CFU-ECs and resting CFU-ECs treated with 0, 1, 5, or 10 U/ml of thrombin. Outcomes were compared between high- and low-active participants. F1+2 and thrombin-antithrombin III, but not CD34+/VEGFR2+ number and CFU-ECs, increased with exercise. Exercise-induced changes in F1+2 correlated with changes in CD34+/VEGFR2+ number in both groups. Thrombin treatments and acute exercise increased cyclin A2 and cyclin D1 expression and decreased p27 expression. One unit per milliliter thrombin increased VEGFR2 and VE-cadherin expression, whereas 5 U/ml, 10 U/ml, and acute exercise did not elicit any changes. An exercise training effect was observed with greater decreases in p27 expression with 5 and 10 U/ml thrombin and greater increases in VEGFR2 and VE-cadherin expression with 1 U/ml thrombin in high-active men. Exercise-induced changes in putative EPC gene expression are associated with thrombin production and may be modulated by long-term exercise training.