bluuebunny/crossref_metadata_2025 huggingface dataset:
Heterologous Plasmid DNA Prime-Recombinant Human Adenovirus 5 Boost Vaccination Generates a Stable Pool of Protective Long-Lived CD8
+
T Effector Memory Cells Specific for a Human Parasite, Trypanosoma cruzi
Authors: Rigato Paula Ordonhez , de Alencar Bruna C. , de Vasconcelos José Ronnie C. , Dominguez Mariana R. , Araújo Adriano F. , Machado Alexandre V. , Gazzinelli Ricardo T. , Bruna-Romero Oscar , Rodrigues Mauricio M.
Published: March 2011

Recently, we described a heterologous prime-boost strategy using plasmid DNA followed by replication-defective human recombinant adenovirus type 5 as a powerful strategy to elicit long-lived CD8
+
T-cell-mediated protective immunity against experimental systemic infection of mice with a human intracellular protozoan parasite,
Trypanosoma cruzi
. In the present study, we further characterized the protective long-lived CD8
+
T cells. We compared several functional and phenotypic aspects of specific CD8
+
T cells present 14 or 98 days after the last immunizing dose and found the following: (i) the numbers of specific cells were similar, as determined by multimer staining or by determining the number of gamma interferon (IFN-γ)-secreting cells by enzyme-linked immunospot (ELISPOT) assay; (ii) these cells were equally cytotoxic
in vivo
; (iii) following
in vitro
stimulation, a slight decline in the frequency of multifunctional cells (CD107a
+
IFN-γ
+
or CD107a
+
IFN-γ
+
tumor necrosis factor alpha positive [TNF-α
+
]) was paralleled by a significant increase of CD107a singly positive cells after 98 days; (iv) the expression of several surface markers was identical, except for the reexpression of CD127 after 98 days; (v) the use of genetically deficient mice revealed a role for interleukin-12 (IL-12)/IL-23, but not IFN-γ, in the maintenance of these memory cells; and (vi) subsequent immunizations with an unrelated virus or a plasmid vaccine or the depletion of CD4
+
T cells did not significantly erode the number or function of these CD8
+
T cells during the 15-week period. From these results, we concluded that heterologous plasmid DNA prime-adenovirus boost vaccination generated a stable pool of functional protective long-lived CD8
+
T cells with an effector memory phenotype.
ArcA-Regulated Glycosyltransferase Lic2B Promotes Complement Evasion and Pathogenesis of Nontypeable Haemophilus influenzae
Authors: Wong Sandy M. S. , St. Michael Frank , Cox Andrew , Ram Sanjay , Akerley Brian J.
Published: March 2011

Signaling mechanisms used byHaemophilus influenzaeto adapt to conditions it encounters during stages of infection and pathogenesis are not well understood. The ArcAB two-component signal transduction system controls gene expression in response to respiratory conditions of growth and contributes to resistance to bactericidal effects of serum and to bloodstream infection byH. influenzae. We show that ArcA of nontypeableH. influenzae(NTHI) activates expression of a glycosyltransferase gene,lic2B.Structural comparison of the lipooligosaccharide (LOS) of alic2Bmutant to that of the wild-type strain NT127 revealed thatlic2Bis required for addition of a galactose residue to the LOS outer core. Thelic2Bgene was crucial for optimal survival of NTHI in a mouse model of bacteremia and for evasion of serum complement. The results demonstrate that ArcA, which controls cellular metabolism in response to environmental reduction and oxidation (redox) conditions, also coordinately controls genes that are critical for immune evasion, providing evidence that NTHI integrates redox signals to regulate specific countermeasures against host defense.
Recognition and Blocking of Innate Immunity Cells by Candida albicans Chitin
Authors: Mora-Montes Héctor M. , Netea Mihai G. , Ferwerda Gerben , Lenardon Megan D. , Brown Gordon D. , Mistry Anita R. , Kullberg Bart Jan , O'Callaghan Chris A. , Sheth Chirag C. , Odds Frank C. , Brown Alistair J. P. , Munro Carol A. , Gow Neil A. R.
Published: March 2011

Chitin is a skeletal cell wall polysaccharide of the inner cell wall of fungal pathogens. As yet, little about its role during fungus-host immune cell interactions is known. We show here that ultrapurified chitin fromCandida albicanscell walls did not stimulate cytokine production directly but blocked the recognition ofC. albicansby human peripheral blood mononuclear cells (PBMCs) and murine macrophages, leading to significant reductions in cytokine production. Chitin did not affect the induction of cytokines stimulated by bacterial cells or lipopolysaccharide (LPS), indicating that blocking was not due to steric masking of specific receptors. Toll-like receptor 2 (TLR2), TLR4, and Mincle (the macrophage-inducible C-type lectin) were not required for interactions with chitin. Dectin-1 was required for immune blocking but did not bind chitin directly. Cytokine stimulation was significantly reduced upon stimulation of PBMCs with heat-killed chitin-deficientC. albicanscells but not with live cells. Therefore, chitin is normally not exposed to cells of the innate immune system but is capable of influencing immune recognition by blocking dectin-1-mediated engagement with fungal cell walls.
Direct Current Electrical Stimulation of Acupuncture Needles for Peripheral Nerve Regeneration: An Exploratory Case Series
Authors: Inoue Motohiro , Katsumi Yasukazu , Itoi Megumi , Hojo Tatsuya , Nakajima Miwa , Ohashi Suzuyo , Oi Yuki , Kitakoji Hiroshi
Published: March 2011

Objective

To examine the therapeutic effect of a novel therapeutic method based on electroacupuncture with intermittent direct current (DCEA) and associated adverse events in patients with peripheral nerve damage and a poor clinical prognosis.

Methods

In seven older patients with peripheral nerve damage (neurapraxia 2, axonotmesis 4, neuromesis 1), an acupuncture needle connected to an anode electrode was inserted proximal to the site of the injury along the route of the nerve, while the cathode electrode was inserted into the innervated muscle, and DCEA was performed (100 Hz for 20 min, weekly). Muscular paralysis was evaluated weekly with manual muscle testing, the active range of motion of joints related to the muscular paralysis and, when necessary, needle electromyography. Adverse events were also recorded during the course of the treatment.

Results

Complete functional recovery was observed in the two cases with neurapraxia and two with axonotmesis, while one axonotmesis case achieved improvement and the other showed reinnervation potential without functional recovery. No improvement was observed in the neurotmesis case. Pigmentation of the skin where the anode needle was inserted occurred in three cases. Although there was no definite causal link, one case showed excessive formation and resorption of bone in the area close to the cathode needle site.

Discussion

Accelerated nerve regeneration caused by DCEA may contribute to recovery. The skin pigmentation and callus formation suggest that the shape of the anode electrode, current intensity and other factors should be examined to establish a safer treatment method.
Effects of lameness, subclinical mastitis and loss of body condition on the reproductive performance of dairy cows
Authors: Peake K. A. , Biggs A. M. , Argo C. M. , Smith R. F. , Christley R. M. , Routly J. E. , Dobson H.
Published: March 2011

A total of 318 cows were monitored in the pre‐breeding postpartum period for the presence of three production stressors: lameness, subclinical mastitis and body condition score (BCS) loss. For each stressor, cows were given a classification of severely, moderately or non‐affected based on mobility scores, somatic cell counts and BCS change. The number of days from calving to onset of the first luteal phase was greater in cows that had one severe production stressor (median 44 days) or two moderate production stressors (41 days) compared with cows that had no stressors (31 days) (P=0.02 and P=0.04, respectively). More than one severe stressor increased the interval further. There was no difference between cows with one moderate stressor (median 38 days) and those with none (P=0.13). The delay to the first luteal phase was significantly longer in cows with two moderate stressors if the onset of one stressor occurred at the time when resumption of ovarian activity was expected. The presence of these production stressors in early lactation had no effect on the interval from calving to establishment of the next pregnancy or the number of inseminations required despite the negative effect on the onset of the luteal phase.
Veterinary opinions on refusing euthanasia: justifications and philosophical frameworks
Authors: Yeates J. W. , Main D. C. J.
Published: March 2011

To obtain information on euthanasia decisions from practising veterinary surgeons, respondents were asked to estimate how often during their time in practice they had refused to euthanase a dog and how often they had wanted to refuse to euthanase a dog but not done so because of other pressures. For each, respondents were then asked to state their most common reasons for refusing/not refusing in free text. The responses of clinicians were considered in the light of established ethical concepts to produce an evidence‐based ethical framework for decision making. In total, 58 practitioners responded. Common reasons given for decisions on whether to refuse euthanasia referred to the patient's interests, such as the possibility of treatment or rehoming, and the fear of other unacceptable outcomes for the dog. Other reasons were based on concern for owners' interests. Some respondents reported being pressured into euthanasia by clients and other veterinary surgeons. This gives insight into the ethical principles that explicitly underlie veterinary surgeons' euthanasia decisions and the resultant framework may be useful for discussing and teaching euthanasia.
A MEAN FIELD APPROACH FOR ISING MODELS ON SCALE-FREE NETWORKS
Authors: IANNONE G. , LUONGO ORLANDO
Published: March 2011

Recently, the study of complex networks led to the analysis of the so-called scale-free models in statistical mechanics. This study has increased its importance, thanks to the wide range of applications in numerous physical contexts; for example, one important question is to understand the behavior of various models on such networks. We start first by investigating the Ising model in the mean field approximation and on scale-free networks, studying especially the Ising model with annealed dilution and Clock model, with particular attention devoted to focusing on similarities between the mean field approximations with or without scale-free statistics. A particular emphasis is given to the possible practical applications of these results in other disciplines such as medicine and social science.
GRAPHENE: SYNTHESIS, FUNCTIONALIZATION AND PROPERTIES
Authors: RAO C. N. R. , SUBRAHMANYAM K. S. , RAMAKRISHNA MATTE H. S. S. , GOVINDARAJ A.
Published: March 2011

Graphenes with varying number of layers can be synthesized by different strategies. Thus, single-layer graphene is obtained by the reduction of single layer graphene oxide, CVD and other methods besides micromechanical cleavage. Few-layer graphenes are prepared by the conversion of nanodiamond, arc-discharge of graphite and other means. We briefly present the various methods of synthesis and the nature of graphenes obtained. We then discuss the various properties of graphenes. The remarkable property of graphene of quenching fluorescence of aromatic molecules is shown to be associated with photo-induced electron transfer, on the basis of fluorescence decay and time-resolved transient absorption spectroscopic measurements. The interaction of electron donor and acceptor molecules with few-layer graphene samples has been discussed. Decoration of metal nano-particles on graphene sheets and the resulting changes in electronic structure are examined. Few-layer graphenes exhibit ferromagnetic features along with antiferromagnetic properties, independent of the method of preparation. Graphene-like MoS2and WS2have been prepared by chemical methods, and the materials are characterized by electron microscopy, atomic force microscopy (AFM) and other methods. Boron nitride analogues of graphene have been obtained by a simple chemical procedure starting with boric acid and urea and have been characterized by various techniques.
TWO-DIMENSIONAL CHANGE-POINT MODELING FOR SOFTWARE RELIABILITY ASSESSMENT
Authors: INOUE SHINJI , FUKUMA KEISUKE , YAMADA SHIGERU
Published: March 2011

Most of software reliability growth models (SRGMs) describe a software reliability growth process depending on only testing-time. However, it is said that a software reliability growth process in an actual testing-phase of a software development process depends on not only testing-time but also testing-effort factors. And we often observe a phenomenon that stochastic characteristics of the software failure-occurrence time or the software failure-occurrence time-interval changes notably in an actual testing-phase. The testing-time when such phenomenon is observed is called change-point. It is said that the effect of change-point on the software reliability growth process influences accuracy for software reliability assessment based on conventional SRGMs. This paper discusses a two-dimensional software reliability growth modeling with change-point for describing an actual phenomenon being related to the software reliability growth process. Further, we show examples of the applications of software reliability assessment based on our two-dimensional SRGM by using actual data.
MAXIMUM ENTROPY AND DISCRETE TIME SOFTWARE RELIABILITY GROWTH MODELS
Authors: ZEEPHONGSEKUL PANLOP , YAMADA SHIGERU
Published: March 2011

This paper provides a preliminary investigation into the application of the Maximum Entropy Principle (MEP), introduced by Jaynes in 1957, in modeling discrete time Software Reliability Growth Model (SRGM). On their own, each of these two topics are interesting with extensive applications, and here we will show how they can be combined to provide yet another application of the MEP among a huge array of proven successful applications. A brief discussion of MEP and SRGM will be given and a hitherto unnoticed relationship between MEP distribution and the Lagrange interpolation polynomials highlighted. We then show how MEP can be used to obtain some important distributions arising from discrete time SRGM. Finally, a simple example is given to illustrate the theory.
Meso-meso phenyl bridged unsymmetrical porphyrin dyads: synthesis, spectral, electrochemical and photophysical properties
Authors: Yedukondalu Meesala , Maity Dilip K. , Ravikanth Mangalampalli
Published: March 2011

Seven phenyl bridged meso-meso unsymmetrical porphyrin dyads containing two different porphyrins either two types of heteroporphyrins or one porphyrin and one heteroporphyrin were synthesized by coupling of readily accessible appropriate mono-meso porphyrin boronate/heteroporphyrin boronate with meso-bromoheteroporphyrin in the presence of Cs2CO3/Pd(PPh}3)4 in toluene/DMF at 80°C for 4 h. The dyads are freely soluble in common organic solvents and were characterized by mass, NMR, absorption, electrochemical and fluorescence techniques. The NMR, absorption and electrochemical studies indicated that the two porphyrin sub-units in dyads interact weakly and they retain their characteristic features. In six out of seven dyads, the free-base porphyrin with N4 core or its Zn(II) derivative possess singlet state energy level at higher energy hence acts as energy donor and the heteroporphyrin sub-unit with N3S , N2SO and N2S2 cores having singlet state energy level at lower energy acts as energy acceptor. Our preliminary photophysical studies on six unsymmetrical porphyrin dyads indicated a possibility of energy transfer at singlet state from donor porphyrin sub-unit to acceptor porphyrin sub-unit on selective excitation of donor porphyrin sub-unit. To gain the structural information and to demonstrate possible electronic interaction between the donor and acceptor porphyrin sub-units, DFT calculations were carried out on dyads 1, 3 and 5 by adopting B3LYP hybrid functional with Gaussian atomic basis functions. The theoretical studies predicted a considerable modification of electronic energy levels in these dyads with the change of porphyrin core in acceptor sub-unit. Calculations also indicate most efficient donor → acceptor energy transfer in case of dyad 5 supporting the experimental results.
GALOIS THEORY OF THE CANONICAL THETA STRUCTURE
Authors: CARLS ROBERT
Published: March 2011

In this article, we give a Galois-theoretic characterization of the canonical theta structure. The Galois property of the canonical theta structure translates into certain p-adic theta relations which are satisfied by the canonical theta null point of the canonical lift. As an application, we prove some 2-adic theta identities which describe the set of canonical theta null points of the canonical lifts of ordinary abelian varieties in characteristic 2. The latter theta relations are suitable for explicit canonical lifting. Using the theory of canonical theta null points, we are able to give a theoretical foundation to Mestre's point counting algorithm which is based on the computation of the generalized arithmetic geometric mean sequence.
ORTHOGONAL SYSTEMS OF MODULAR FORMS AND SUPERSINGULAR POLYNOMIALS
Authors: BABA SRINATH , GRANATH HÅKAN
Published: March 2011

We extend a construction of Kaneko and Zagier to obtain modular forms which, modulo a prime, vanish at the supersingular points. These modular forms arise simultaneously as solutions of certain second-order differential equations, and as an orthogonal basis for an inner product on the space of modular forms.
A REVIEW OF THE APPLICATIONS OF NANOCARBON POLYMER COMPOSITES
Authors: RAHMAN ATEEQ , ALI ILIAS , AL ZAHRANI SAEED M. , ELEITHY RABEH H.
Published: March 2011

Nanotechnology offers fundamentally new capabilities to architect a broad array of novel materials, composites and structures on a molecular scale. It is potentially capable of redefining the methods used for developing lighter, stronger, high-performance structures and processes with unique and nontraditional properties. This review summarizes different classes of nanocarbon-based polymer composites and their applications. Also, it highlights different ways to create smaller, cheaper, lighter and faster devices using nanocarbon-based polymer composites. The potential applications of such materials are in the fields of membrane, aviation, electronics, polymer composites, as well as the marine and transport industries. A detailed description of nanocarbon-based composite materials manufactured from PE, PP, PS, PS, PVC, PPS, ABS, PMMA, nitrile rubber, etc. is also reviewed. Some of the major applications of carbon-based polymer nanocomposites are in the tyre industry, semiconductors, and many more, which has brought about the new, developing and exciting research field called nanoscience.
THE REGIONAL ENGINEERING DAMAGE AND RECONSTRUCTION STRATEGY IN WENCHUAN EARTHQUAKE OF CHINA
Authors: OU J. P. , LI H.
Published: March 2011

Wenchuan earthquake, occurred on 12 May 2008, has caused a catastrophe. This paper first presents an overview of this earthquake disaster. The characteristics of earthquake ground motion records are analyzed. The geohazards, seismic damage of hydraulic engineering structures, building structures, structures for transportation, and their chain effects are summarized. Policies and actions on emergency rescue, relief, settlement, earthquake damage assessment and evaluation, the plan on retrofitting school buildings, and recovery are also introduced. The status of the reconstruction is also surveyed and presented. Finally, the suggestions pertaining to key scientific and technological issues on earthquake disaster prevention and mitigation, and the systematic recovery actions are put on record.
ASSESSMENT OF DAMAGE AND LOSS OF SEISMICALLY EXCITED STRUCTURES BASED ON CONVEX ANALYSIS
Authors: LI H. , JIA L. Z.
Published: March 2011

Probabilistic results drawn upon inadequate information are suspicious. The convex set theory, which requires much less information, is employed to model the uncertainties of the spectral displacement and damage state medians. Furthermore, a convex model of fragility function is established based on the envelope bound convex models of the spectral displacement and damage state medians. A bound loss estimation method is derived by integrating HAZUS-AEBM module with the convex set theory. The loss bounds of a hotel in southern China are obtained and compared to the loss calculated by HAZUS-AEBM method, which locates in the lower half interval of convex analysis results. The uncertainty propagation is analyzed and damage state medians are found to be the most critical factor to the loss. Finally, the PEER's probabilistic loss estimation methodology is also applied to this example to deduce the probability of loss exceeding the bound values of convex analysis results.
Twitter as medium and message
Authors: Savage Neil
Published: March 2011

Researchers are mining Twitter's vast flow of data to measure public sentiment, follow political activity, and detect earthquakes and flu outbreaks.
Evaluating government funding
Authors: Geller Tom
Published: March 2011

Presidential report asserts the value of U.S. government funding and specifies areas needing greater focus.
Gary Chapman, technologist
Authors: Greengard Samuel
Published: March 2011

He raised important public issues, such as the impact of computers and the Internet on society, and encouraged social responsibility for computer professionals.
Do you own the software you buy?
Authors: Samuelson Pamela
Published: March 2011

Examining the fine print concerning your rights in your copies of purchased software.
Surrounded by machines
Authors: Pimple Kenneth D.
Published: March 2011

A chilling scenario portends a possible future.
B.Y.O.C (1,342 times and counting)
Authors: Kamp Poul-Henning
Published: March 2011

Why can't we all use standard libraries for commonly needed algorithms?
Plug-and-play macroscopes
Authors: Börner Katy
Published: March 2011

Compose "dream tools" from continuously evolving bundles of software to make sense of complex scientific data sets.
Understanding scam victims
Authors: Stajano Frank , Wilson Paul
Published: March 2011

Effective countermeasures depend on first understanding how users naturally fall victim to fraudsters.
VL2
Authors: Greenberg Albert , Hamilton James R. , Jain Navendu , Kandula Srikanth , Kim Changhoon , Lahiri Parantap , Maltz David A. , Patel Parveen , Sengupta Sudipta
Published: March 2011

To be agile and cost effective, data centers must allow dynamic resource allocation across large server pools. In particular, the data center network should provide a simple flat abstraction: it should be able to take any set of servers anywhere in the data center and give them the illusion that they are plugged into a physically separate, noninterfering Ethernet switch with as many ports as the service needs. To meet this goal, we present VL2, a practical network architecture that scales to support huge data centers with uniform high capacity between servers, performance isolation between services, and Ethernet layer-2 semantics. VL2 uses (1) flat addressing to allow service instances to be placed anywhere in the network, (2) Valiant Load Balancing to spread traffic uniformly across network paths, and (3) end system--based address resolution to scale to large server pools without introducing complexity to the network control plane. VL2's design is driven by detailed measurements of traffic and fault data from a large operational cloud service provider. VL2's implementation leverages proven network technologies, already available at low cost in high-speed hardware implementations, to build a scalable and reliable network architecture. As a result, VL2 networks can be deployed today, and we have built a working prototype. We evaluate the merits of the VL2 design using measurement, analysis, and experiments. Our VL2 prototype shuffles 2.7 TB of data among 75 servers in 395 s---sustaining a rate that is 94% of the maximum possible.
Future Tense: Catch me if you can
Authors: Benford Gregory
Published: March 2011

Future Tense, one of the revolving features on this page, presents stories and essays from the intersection of computational science and technological speculation, their boundaries limited only by our ability to imagine what will and could be.

Or how to lose a billion in your spare time…
Reaching out to the media
Authors: Rosamond Frances , Bardohl Roswitha , Diehl Stephan , Geisler Uwe , Bolduan Gordon , Lessmöllmann Annette , Schwill Andreas , Stege Ulrike
Published: March 2011

Why computer scientists should come out from "behind the scenes" more often and work with the media to draw public attention to their fundamental innovations.
Web Art Science Camp London 2010
Authors: Matias J. Nathan
Published: March 2011

Web Art Science Camp London was a day of ideas, fun, and creativity with Hypertext and the web. Open to anyone, our unconference was abuzz with fascinating ideas and demos across hypertext, the arts, and web science. In addition to introducing newcomers to SIGWEB, we also raised several hundred pounds for student travel bursaries. Our aim was to open up SIGWEB's work to new audiences and experiment with the potential of informal gatherings for sparking new collaborative research ideas. The resulting event was splendid, and the organising team hopes that our lessons can be applied to other regions and further UK events. http://doi.acm.org/10.1145/1942800.1942801.
Interview with Peter King
Authors: Atzenbeck Claus
Published: March 2011

Dr. Peter King has been active in digital documents and hypertext for almost thirty years. He was one of the founders of the Electronic Publishing conference series and of the ACM Symposium on Document Engineering, whose Steering Committee he now chairs. He holds the position of Professor Emeritus of Computer Science at the University of Manitoba in Winnipeg, Canada. He has recently held research positions at the University of Kent, UK and at LIRMM, Montpellier, France, and has worked at several other European and Canadian research institutes.

Peter's work in document engineering covers several areas. He has performed individual and collaborative work on formalisms for multimedia document specification and on document description languages and systems, leading to the creation of several working systems. He has collaborated on work on hypertext, including the OPALES system and its successors, and on hypertext architectures supporting collaborative document usage and user communities. His joint work with Marc and Jocelyne Nanard won the ACM Engelbart award for best paper at the Hypertext 2003 Conference. Prior to developing his interest in document engineering and hypertext, he worked extensively in the area of programming language design and implementation.

Peter King is a leader in computing education and educational standards. He is Director of Accreditation for CIPS, the Canadian Information Processing Society, which establishes and assesses industry recognized standards for postsecondary computing education in university and college institutions across Canada and internationally.
Towards behaviour-driven transcoding of web content through an analysis of user coping strategies
Authors: Lunn Darren
Published: March 2011

Darren Lunn is a research associate at the University of Manchester, working in the Web Ergonomics Lab. Darren completed his PhD in 2009 at the School of Computer Science at the University of Manchester under the supervision of Simon Harper and Sean Bechhofer. His PhD thesis was entitled
Towards Behaviour-Driven Transcoding of Web Content Through an Analysis of User Coping Strategies
where a transcoding engine was developed that modified Web content based on annotations of the Cascading Style Sheets associated with the page. This was coupled with a framework that was developed to allow strategies to be identified that visually impaired users employed to overcome Web content that was difficult to interact with. This framework was used to develop the adaptations incorporated into the transcoding engine and allowed easier access to Web content for visually impaired users. A complete copy of the thesis can be found at: http://wel-eprints.cs.manchester.ac.uk/127/.
Assisting cross-lingual editing in collaborative writing
Authors: Au Yeung Ching-man , Duh Kevin , Nagata Masaaki
Published: March 2011

Wikis have enabled Web users to author and edit documents in a collaborative manner. In many cases such as Wikipedia and Wikibooks, they have been used to host a set of parallel or comparable documents written in different languages. While a wiki provides an environment in which editors can work together efficiently, maintaining a set of multi-lingual documents is still a very demanding task for the editors. When documents in different languages are maintained by different groups of editors, it is even harder for a contributor to determine whether some information is missing and should be translated from one language to another. In this article, we briefly describe a framework that can be used to assist authors and editors in collaborative writing to perform cross-lingual editing.
Bothnia
Authors: Chinya Gautham N. , Collins Jamison D. , Wang Perry H. , Jiang Hong , Lueh Guei-Yuan , Piazza Thomas A. , Wang Hong
Published: March 2011

In this paper, we introduce Bothnia, an extension to the Intel production graphics driver to support a shared virtual memory heterogeneous multithreading programming model. With Bothnia, the Intel graphics device driver can support both the traditional 3D graphics rendering software stack and a new class of heterogeneous multithreaded applications, which can use both IA (Intel Architecture) CPU cores and Intel integrated Graphics and Media Accelerator (GMA) cores in the same virtual address space. We describe the necessary architectural supports in both IA CPU and the GMA cores and present a reference Bothnia implementation. For a set of GPU accelerated media applications on a PC platform with Intel Core 2 Duo CPU and the Intel integrated GMA X3000 running under the Windows XP operating system, Bothnia achieves an average speedup of 3.6x compared to using the GPU as a device, primarily due to Bothnia's support for creation of shared virtual address space between heterogeneous threads of the same application spread on both IA CPU and GMA cores.
Efficient interaction between OS and architecture in heterogeneous platforms
Authors: Srinivasan Sadagopan , Zhao Li , Illikkal Ramesh , Iyer Ravishankar
Published: March 2011

Almost all hardware platforms to date have been homogeneous with one or more identical processors managed by the operating system (OS). However, recently, it has been recognized that power constraints and the need for domain-specific high performance computing may lead architects towards building heterogeneous architectures and platforms in the near future. In this paper, we consider the three types of heterogeneous core architectures: (a) Virtual asymmetric cores: multiple processors that have identical core micro-architectures and ISA but each running at a different frequency point or perhaps having a different cache size, (b) Physically asymmetric cores: heterogeneous cores, each with a fundamentally different microarchitecture (in-order vs. out-of-order for instance) running at similar or different frequencies, with identical ISA and (c) Hybrid cores: multiple cores, where some cores have tightly-coupled hardware accelerators or special functional units. We show case studies that highlight why existing OS and hardware interaction in such heterogeneous architectures is inefficient and causes loss in application performance, throughput efficiency and lack of quality of service. We then discuss hardware and software support needed to address these challenges in heterogeneous platforms and establish efficient heterogeneous environments for platforms in the next decade. In particular, we will outline a monitoring and prediction framework for heterogeneity along with software support to take advantage of this information. Based on measurements on real platforms, we will show that these proposed techniques can provide significant advantage in terms of performance and power efficiency in heterogeneous platforms.
Log-based architectures
Authors: Chen Shimin , Gibbons Phillip B. , Kozuch Michael , Mowry Todd C.
Published: March 2011

While application performance and power-efficiency are both important, application correctness is even more important. In other words, if the application is misbehaving, it is little consolation that it is doing so quickly or power-efficiently. In the Log-Based Architectures (LBA) project, we are focusing on a challenging source of application misbehavior: software bugs, including obscure bugs that only cause problems during security attacks. To help detect and fix software bugs, we have been exploring techniques for accelerating dynamic program monitoring tools, which we call "lifeguards". Lifeguards are typically written today using dynamic binary instrumentation frameworks such as Valgrind or Pin. Due to the overheads of binary instrumentation, lifeguards that require instructiongrain information typically experience 30X-100X slowdowns, and hence it is only practical to use them during explicit debug cycles. The goal in the LBA project is to reduce these overheads to the point where lifeguards can run continuously on deployed code. To accomplish this, we propose hardware mechanisms to create a dynamic log of instruction-level events in the monitored application and stream this information to one or more software lifeguards running on separate cores on the same multicore processor. In this paper, we highlight techniques and features of LBA that reduce the slowdown to just 2%--51% for sequential programs and 28%--51% for parallel programs.
Optimizing a shared virtual memory system for a heterogeneous CPU-accelerator platform
Authors: Yan Shoumeng , Zhou Xiaocheng , Gao Ying , Chen Hu , Wu Gansha , Luo Sai , Saha Bratin
Published: March 2011

The client computing platform is moving towards a heterogeneous architecture that combines scalar-oriented CPU cores and throughput-oriented accelerator cores. Recognizing that existing programming models for such heterogeneous platforms are still difficult for most programmers, we advocate a shared virtual memory programming model to improve programmability. In this paper, we focus on performance, and demonstrate that users need not sacrifice performance for programmability. We describe our approaches, experiences, and results in optimizing MYO on a heterogeneous platform consisting of a CPU and an Aubrey Isle accelerator. Our efforts involve the whole system software stack including the OS, runtime, and application.
RouteBricks
Authors: Fall Kevin , Iannaccone Gianluca , Manesh Maziar , Ratnasamy Sylvia , Argyraki Katerina , Dobrescu Mihai , Egi Norbert
Published: March 2011

We revisit the problem of scaling software routers, motivated by recent advances in server technology that enable highspeed parallel processing a feature router workloads appear ideally suited to exploit. We propose a software router architecture that parallelizes router functionality both across multiple servers and across multiple cores within a single server. By carefully exploiting parallelism at every opportunity, we demonstrate a 40Gbps parallel router prototype; this router capacity can be linearly scaled through the use of additional servers. Our prototype router is fully programmable using the familiar Click/Linux environment and is built entirely from off-the-shelf, general-purpose server hardware. We also describe some of the lessons learned while supporting field deployments of Routebricks-based software routers.
Small trusted primitives for dependable systems
Authors: Maniatis Petros , Chun Byung-Gon
Published: March 2011

Secure, fault-tolerant distributed systems are difficult to build, to validate, and to operate. Conservative design for such systems dictates that their security and fault tolerance depend on a very small number of assumptions taken on faith; such assumptions are typically called the "trusted computing base" (TCB) of a system. However, a rich trade-off exists between larger TCBs and more secure, more faulttolerant, or more efficient systems. In our recent work, we have explored this trade-off by defining "small," generic trusted primitives--for example, an attested, monotonically sequenced FIFO buffer of a few hundred machine words guaranteed to hold appended words until eviction and showing how such primitives can improve the performance, fault tolerance, and security of systems using them. In this article, we review our efforts in generating simple trusted primitives such as an attested circular buffer (called Attested Appendonly Memory), and an attested human activity detector. We describe the benefits of using these primitives to increase the fault-tolerance of replicated systems and archival storage, and to improve the security of email SPAM and click-fraud prevention systems. Finally, we share some lessons we have learned from this endeavor.
TaintEraser
Authors: Zhu David (Yu) , Jung Jaeyeon , Song Dawn , Kohno Tadayoshi , Wetherall David
Published: March 2011

We present TaintEraser, a new tool that tracks the movement of sensitive user data as it flows through off-the-shelf applications. TaintEraser uses application-level dynamic taint analysis to let users run applications in their own environment while preventing unwanted information exposure. It is made possible by techniques we developed for accurate and efficient tainting: (1) Semantic-aware instruction-level tainting is critical to track taint accurately, without explosion or loss. (2) Function summaries provide an interface to handle taint propagation within the kernel and reduce the overhead of instruction-level tracking. (3) On-demand instrumentation enables fast loading of large applications. Together, these techniques let us analyze large, multi-threaded, networked applications in near real-time. In tests on Internet Explorer, Yahoo! Messenger, and Windows Notepad, Taint- Eraser generated no false positives and instrumented fewer than 5% of the executed instructions while precisely scrubbing user-defined sensitive data that would otherwise have been exposed to restricted output channels. Our research provides the first evidence that it is viable to track taint accurately and efficiently for real, interactive applications running on commodity hardware.
VII Brazilian workshop on operating systems
Authors: da Silva Dilma , Barreto Luciano , Pereira Paulo César A.
Published: March 2011

This paper reports on the VII Brazilian Workshop on Operating Systems.
Abstract specification and formalization of an operating system kernel in Z
Authors: Barreto Luciano , Andrade Aline , Duran Adolfo , Lima Caique , Lima Ademilson
Published: March 2011

One of the mini challenges in software verification related to the Grand Challenge proposed by Tony Hoare concerns the formal specification and verification of an operating system kernel. This paper proposes a simple and correct specification of an OS kernel in Z which simplifies the understanding and verification of operating system components. Our current specification comprises process management, interprocess communication and a POSIX-compliant file system.
Online mathematics manipulation for the visually impaired
Authors: Alajarmeh Nancy
Published: March 2011

Mathematics manipulation accessibility is a newly discussed and introduced research area extending the general mathematics accessibility approaches on the web. This project goes further beyond what researchers already started in mathematics rendering accessibility approaches; so that the final outcome we aim into is allowing visually impaired students to have some manipulation controls over the rendered mathematical algebraic expressions; i.e. solving an equation, have a complete history of doing mathematics (algebra) in steps they perform to reach what they are looking for, exactly the same as giving them a pencil and a piece of paper to do whatever they see appropriate to get a final simplified equation or result.
REACT
Authors: Boujarwah Fatima A , Riedl Mark O , Abowd Gregory D , Arriaga Rosa I
Published: March 2011

Difficulties in social skills are generally considered defining characteristics of High-functioning Autism (HFA). These difficulties interfere with the educational experiences and quality of life of individuals with HFA, and interventions must be highly individualized to be effective. For these reasons, we are interested in exploring the way technologies may play a role in assisting individuals with the acquisition of social skills. In this article we present an approach to developing an authoring tool designed to help parents and other caregivers to create social problem solving skills instructional modules. The authoring tool, which we call REACT, will help non-experts create interactive social scenarios personalized to individual adolescents with HFA. The technology will assist by advising the author on instructional strategies, and on scenario creation.
Towards designing more accessible interactions of older people with digital TV
Authors: Ferreira Susan , Sayago Sergio , Arroyo Ernesto , Blat Josep
Published: March 2011

This paper outlines an ongoing PhD thesis about accessibility, DTV (Digital TV) and older people. We aim to design and evaluate accessible interactions of older people with DTV services enabling communication and access to information about health and wellbeing. DTV opens up a wide range of opportunities for older people to communicate with their social circles and access online information. However, DTV services are far from being accessible to older people. We aim to fill this gap by addressing three relevant and up to now relatively unexplored areas in DTV accessibility research with older people: interaction barriers, everyday use of DTV services enabling communication and access to information about health, and cultural differences in both interaction and use. We will use key ethnographical methods to understand these aspects with two user groups of older people living in developed and developing countries (Spain and Brazil). We will also design and evaluate interactive prototypes of related DTV services by drawing upon the ethnographical data, and involving older people in the design and evaluation (participatory design) process.
Promoting sharing behaviours in children through the use of a customised novel computer system
Authors: Menzies Rachel
Published: March 2011

Asperger Syndrome is a condition on the Autism Spectrum, characterised by a lack of ability to recognise and understand the thoughts, beliefs, desires and intentions of others. Thus, the ability to make sense of others' behaviours and predict their social actions is reduced.

This paper aims to develop a technology-enhanced learning environment in which children with Asperger Syndrome can explore and improve their sharing skills. This may increase their social awareness and interaction. The system is scenario-based, with each scenario focussing on a specific aspect of sharing. It is expected that, through the user-centred development and implementation of this system, children who previously were socially isolated will be more capable of becoming more socially networked as individuals. This will have implications on learning and interaction.
Accessible design through shared user modelling
Authors: Montague Kyle
Published: March 2011

In the proposed thesis, research examines possible exploitations of shared user modelling in order to improve the accuracy and scope of models used for personalisation within touch screen mobile devices to improve the accessibility and usability of software applications. Previous work in adaptive user interfaces has relied on local and domain specific user models, which lack in scope and detail. Shared user models can increase the accuracy and depth of data used to adapt the interfaces and user interactions.
Developing a phoneme-based talking joystick for nonspeaking individuals
Authors: Trinh Ha
Published: March 2011

This research investigates the potential of developing a novel phoneme-based assistive communication system for pre-literate individuals with severe speech and physical impairments. Using a force-feedback joystick-like game controller as the access tool, the system enables users to select forty-two phonemes (i.e., English sounds) used in literacy teaching and combine them together to generate spoken messages. What distinguishes this phoneme-based device from other communication systems currently available on the market is that it allows users who have not mastered literacy skills to create novel words and sentences without the need for a visual interface. Natural Language Processing (NLP) technologies, including phoneme-to-speech synthesis, phoneme-based disambiguation and prediction, and haptic force feedback technology are being incorporated into the device to improve its accessibility and usability.
Immersive virtual exercise environment for people with lower body disabilities
Authors: Zhang Shaojie , Banerjee P. Pat , Luciano Cristian
Published: March 2011

This paper presents the development and evaluation of the use of virtual reality technology, together with appropriately adapted exercises through an augmented reality interface, to create Virtual Exercise Environments (VEEs). These environments allow persons with lower body disabilities to exercise and train just like what people do in real world. The major aim of this research is an architecture to create virtual exercise environments for people with lower body disabilities, which can make exercise more enjoyable and less repetitive. This paper presents our current research on this architecture to facilitate participation and adherence using a VEE as a prototype and common-off-the-shelf hardware components.
Accessible electronic health records
Authors: Sears Andrew , Hanson Vicki
Published: March 2011

An NSF-sponsored workshop, convened in October 2010, addressed the question of a research agenda that would lead to accessible electronic health records. The highest priority identified research areas included addressing the challenges people experience as a result of temporary disabilities; understanding and addressing the issues faced by older adults; investigating the efficacy of personalization technologies for improving accessibility; documenting the current state-of-the-art with regard to the accessibility of existing electronic health records; and carefully documenting the potential benefits of accessible electronic health records for various audiences and with regard to potential improvements in one's health.
Oxidative Stress and Cell Membranes in the Pathogenesis of Alzheimer's Disease
Authors: Axelsen Paul H. , Komatsu Hiroaki , Murray Ian V. J.
Published: March 2011

Amyloid β proteins and oxidative stress are believed to have central roles in the development of Alzheimer's disease. Lipid membranes are among the most vulnerable cellular components to oxidative stress, and membranes in susceptible regions of the brain are compositionally distinct from those in other tissues. This review considers the evidence that membranes are either a source of neurotoxic lipid oxidation products or the target of pathogenic processes involving amyloid β proteins that cause permeability changes or ion channel formation. Progress toward a comprehensive theory of Alzheimer's disease pathogenesis is discussed in which lipid membranes assume both roles and promote the conversion of monomeric amyloid β proteins into fibrils, the pathognomonic histopathological lesion of the disease.