bluuebunny/crossref_metadata_2025 huggingface dataset:
Automatic size determination of membrane vesicles by freeze‐fracture electron microscopy
Authors: Starink J. P. P. , Verkleij A. J.
Published: October 2012

In biological processes involving membrane vesicles, the vesicle sizes and the size distribution of the vesicle population are usually important process parameters. A previous method for determining these parameters by freeze‐fracture electron microscopy exclusively makes use of concave profiles with half‐cast shadow, the so‐called equatorial profiles. This method suffers from two disadvantages: (i) the measurement is done manually and is therefore subjective, and (ii) only a small subpopulation of the profiles, those showing half‐cast shadow, can be used.

We describe an automatic, computerized method with which the vesicle size can be calculated from any concave profile with cast shadow. This method is based on the relationship between the angle of shadowing and the surface areas of the profile and the profile's uncoated region. Since the vesicles are processed automatically, the procedure is reproducible and not biased by subjective measurements.

The method was tested both on synthetic, computer‐generated profiles and on large unilamellar vesicles. It allows for the use of about four times as many profiles as the equator method in determining the vesicle size distribution. This means that the distribution is more reliable thanks to the larger population used for its determination. Furthermore, the reliability of our method is exemplified by its stability concerning errors in its parameters.
Hierarchical Narrative Collage For Digital Photo Album
Authors: Zhang Lei , Huang Hua
Published: October 2012

Collage can provide a summary form on the collection of photos in an album. In this paper, we introduce a novel approach to constructing photo collage in the hierarchical narrative manner. As opposed to previous methods focusing on spatial coherence in the collage layout, our narrative collage arranges the photos according to the basic narrative elements from literary writings, i.e., character, setting and plot. Face, time and place attributes are exploited to embody those narrative elements in the collage. Then, photos are organized into the hierarchical structure for the multi‐level details in the events recorded by the album. Such hierarchical narrative collage can present a visual overview in the chronological order on what happened in the album. Experimental results show that our approach offers a better summarization to browse on the photo album content than previous ones.
The Adjustment of Housing Markets to Migration Change: Lessons from Modern History
Authors: Meen Geoffrey
Published: October 2012

This study is concerned with two issues: first, the factors that determine the local location decisions of migrants within the UK and, second, the impact of migrant communities on domestic housing markets. Most migration studies are concerned with the determinants of international migration to the UK. Few look at the drivers of the spatial distributions once migrants arrive. However, migrant housing is primarily a local, urban problem and, arguably, the main issue is the spatial concentrations, rather than absolute numbers. The UK has experienced waves of migrants throughout its history and these are well documented in the censuses since the mid 19th century. A feature of the study is its long‐run perspective, which allows the examination of the characteristics of the different waves and shows the high degree of persistence in spatial structures. The second part of the study examines why there is little evidence that migration has much effect on house prices, despite the popular perception that the impact is important. The study demonstrates that the nature of housing market adjustment is more complex than price indicators alone would suggest. Adjustment also takes place through changes to household formation and through the mobility of domestic residents, which mitigate the price effects.
ESTIMATING THE SIZE OF THE IRREGULAR MIGRANT POPULATION IN PRAGUE – AN ALTERNATIVE APPROACH
Authors: MEDOVÁ LENKA , DRBOHLAV DUŠAN
Published: October 2012

This paper's primary objective is to contribute to the ‘never‐ending story’ of estimating irregular migration. It presents an attempt to develop an empirically based approach/technique for estimating the size of an irregular migrant population, or more specifically of irregularly residing immigrants within the city of Prague. A pilot study, based on discovering the actual number of immigrants residing in selected localities, was conducted via observations and inquiries to local residents, and, subsequently, by comparing these numbers with local official statistics concerning inhabitants. Getting to know the types of built environment in selected localities aided in efforts to extrapolate an estimate for the entire city. Moreover, the spatial distribution of irregular migrants within a city is discussed.
WHAT TYPE OF HISTORIAN? CONCEPTUAL HISTORY AND THE HISTORY OF CONCEPTS: A COMPLEX LEGACY AND A RECENT CONTRIBUTION
Authors: Cuttica Cesare
Published: October 2012

Javier Fernández Sebastián's edited collections of essays, Political Concepts and Time, is both a critical homage to the monumental work of Reinhart Koselleck (1923–2006) and an important contribution to the methodology of history‐writing. Centered on the polysemic nature of concepts, which are read as “‘vehicles for thought’” studied in their pragmatic and communicative applications in society, Political Concepts and Time provides a stimulating analysis of the role, weight, and future of conceptual history.

Its thirteen essays offer an account of problems, questions, and debates on the interplay of words and concepts, meaning and historical change, context and discourse. They endeavor to clarify the complicated and perennially unresolved relationship between theory and practice. In order to do so, Fernández Sebastián has assembled a scholarly composite and broadly international group of specialists from a variety of disciplines and research fields.

With the intellectual legacy of Koselleck's Begriffsgeschichte looming large, this book rethinks the ways in which not just historians but also social scientists and philosophers study the past as the expression of contingent, ever‐changing, and revocable semantic units shaping the culturally plural worlds we inhabit. Informed by the idea that history is porous, Political Concepts and Time also deals with the perhaps obvious but no less challenging issue of our approach to time as everyday experience and through its representation(s).

Together with exploring the volume's specific historical topics, this essay will highlight some of its limitations and, above all, will respond to its criticism of intellectual history. The following pages will thus argue the case for the latter methodological perspective by reflecting on the type of historian it delineates. Claiming that in their investigation of past meanings intellectual historians make use of creative imagination, the essay will suggest that this model of history‐writing leads to a better understanding of multiple sources and that it might ultimately help overcome some of the inconsistencies and often simplistic divisions between various branches of the historiographical tree. In particular, a small proposal to reconcile conceptual and intellectual history will be advanced.
Hypertrichosis Lanuginosa Congenita Treated with Diode Laser Epilation During Infancy
Authors: Salas‐Alanis Julio C. , Lopez‐Cepeda Larissa D. , Elizondo‐Rodriguez Aurora , Morales‐Barrera Maria Enriqueta , Ramos‐Garibay Alberto R.
Published: October 2012

We report the case of a girl with hypertrichosis lanuginosa congenita treated with diode laser depilation since the age of 9 months. The treatment was well tolerated, and neither general nor local anesthesia was needed. A reduction of approximately 80% of facial and body hair was noted, which improved her condition significantly.
Hallucinogens and Cannabinoids for Headache
Authors: McGeeney Brian E.
Published: October 2012

Most hallucinogens and cannabinoids fall into Federal Controlled Substances schedule 1, meaning they cannot be prescribed by practitioners, allegedly have no accepted medical use, and have a high abuse potential. The legal and regulatory status has inhibited clinical research on these substances such that there are no blinded studies from which to assess true efficacy. Despite such classification, hallucinogens and cannabinoids are used by patients with headache on occasion. Cannabinoids in particular have a long history of use for headache and migraine before prohibition and are still used by patients as a migraine abortive. Hallucinogens are being increasing used by cluster headache patients outside of physician recommendation mainly to abort a cluster period and to maintain quiescence for which there is considerable anecdotal success.
Modeling Teacher Beliefs and Practices in Context: A Multimethods Approach
Authors: NISHINO TAKAKO
Published: October 2012

This study investigates the relationship among Japanese high school teachers’ beliefs, their practices, and socioeducational factors regarding communicative language teaching (CLT). A multimethods approach was used consisting of a survey, interviews, and class observations. A Teacher Beliefs Questionnaire was sent to 188 randomly selected Japanese high schools, and 139 teachers responded. Additionally, 12 English classes taught by 4 Japanese high school teachers were observed, focusing on how they used communicative activities. The same 4 teachers were later interviewed. A path model based on Borg's (2003) conceptual framework of teacher cognition was tested. The best‐fitting model indicated that Student‐Related Communicative Conditions directly impacted Classroom Practices, Positive CLT Beliefs indirectly influenced Classroom Practices via CLT Self‐Efficacy, and Exam‐Related Expectations both directly and indirectly affected Classroom Practices. Findings from the interviews and observations revealed that the participants’ learning experiences, in‐service training, and contextual factors (e.g., university entrance examinations) influenced their beliefs and practices.
Barriers to Electronic Prescribing: Nebraska Pharmacists’ Perspective
Authors: Lander Lina , Klepser Donald G. , Cochran Gary L. , Lomelin Daniel E. , Morien Marsha
Published: October 2012

Purpose: Electronic prescribing (e‐prescribing) and its accompanying clinical decision support capabilities have been promoted as means for reducing medication errors and improving efficiency. The objectives of this study were to identify the barriers to adoption of e‐prescribing among nonparticipating Nebraska pharmacies and to describe how the lack of pharmacy participation impacts the ability of physicians to meet meaningful use criteria.

Methods: We interviewed pharmacists and/or managers from nonparticipating pharmacies to determine barriers to the adoption of e‐prescribing. We used open‐ended questions and a structured questionnaire to capture participants’ responses.

Findings: Of the 23 participants, 10 (43%) reported plans to implement e‐prescribing sometime in the future but delayed participation due to transaction fees and maintenance costs, as well as lack of demand from customers and prescribers to implement e‐prescribing. Nine participants (39%) reported no intention to e‐prescribe in the future, citing start‐up costs for implementing e‐prescribing, transaction fees and maintenance costs, happiness with the current system, and lack of understanding about e‐prescribing's benefits and how to implement e‐prescribing.

Conclusions: The barriers to e‐prescribing identified by both late adopters and those not willing to accept e‐prescriptions were similar and were mainly initial costs and transaction fees associated with each new prescription. For some rural pharmacies, not participating in e‐prescribing may be a rational business decision. To increase participation, waiving or reimbursing transaction fees, based on demographic or financial characteristics of the pharmacy, may be warranted.
A proposed theoretical model of help‐seeking among Korean‐American women with urinary incontinence
Authors: Kang Youngmi
Published: October 2012

ABSTRACT

There is no integrated theoretical model explaining help‐seeking for urinary incontinence (UI) that links individual factors to socio‐cultural and systemic factors among Korean‐American women. The purpose of this article was to develop a theoretical model derived from a systemic perspective to explain the help‐seeking among Korean‐American women with UI. The Behavioural Model for Vulnerable Populations derived from a systemic perspective was adapted to develop a theoretical model. Individual factors (i.e. biological risk factors, health beliefs, social structure, income, a regular source of health care and perceived need), systemic factors (i.e. social support and transportation), and unique cultural factors (i.e. acculturation, family tradition and authority, and the preference of a health care provider) were included in the theoretical model. A proposed theoretical model in this article will give an opportunity to understand the relationships among factors that influence to help‐seeking among Korean‐American women with UI. This will be helpful to design culturally competent UI care intervention for Korean‐American women.
Structural tuning and plasticity of the axon initial segment in auditory neurons
Authors: Kuba Hiroshi
Published: October 2012

Abstract  The axon initial segment (AIS) that separates axonal and somato‐dendritic compartments is a highly specialised neuronal structure enriched with voltage‐gated Na+ channels and functions as the site of spike initiation in neurons. The AIS was once thought to be uniform and static in structure, but has been found to be organised in a manner specific to the function of individual neurons and to exhibit plasticity with changes in synaptic inputs. Such structural specialisations are found in the avian auditory system. In the nucleus magnocellularis (NM), which is involved in a precise relay of timing information, the length of the AIS differs depending on sound frequency and increases with decreasing frequencies to accommodate frequency‐specific variations in synaptic inputs. In the nucleus laminaris, which integrates the timing information from both NMs for sound localisation, the length and the location of the AIS vary depending on sound frequency: AISs are shorter and more remote for higher frequency. Furthermore, the AISs of NM neurons elongate to increase their excitability when synaptic inputs are removed by cochlea ablation, suggesting their contribution to the homeostatic control of neural activity. These structural tunings and plasticities of the AIS are thus indispensable for the function of the auditory circuits in both normal and pathological conditions.
A Two-Pressure Humidity Generator
Authors: Durand Keith , Slocum Alexander
Published: October 2012

A device for precisely humidifying a process gas is presented, with particular application to document preservation. The machine is designed to minimize the risk of damage from overpressure by incorporating multiple safety mechanisms and a simple user interface. The design theory is presented, discussed, and verified. This device is capable of generating humidified gases with relative humidities between 7% and 96% to high accuracy. At conditions suitable for document preservation, the machine is accurate to within ±3.5%, generating a relative humidity of (40±1.4)%.
Fks1 and Fks2 Are Functionally Redundant but Differentially Regulated in Candida glabrata: Implications for Echinocandin Resistance
Authors: Katiyar Santosh K. , Alastruey-Izquierdo Ana , Healey Kelley R. , Johnson Michael E. , Perlin David S. , Edlind Thomas D.
Published: October 2012

The echinocandins caspofungin, micafungin, and anidulafungin, inhibitors of cell wall β-1,3-glucan synthesis, were recently elevated to first-line agents for treating infections due to the azole-refractory yeast
Candida glabrata
. In
Candida albicans
, echinocandin resistance is strictly associated with mutations in Fks1, a large integral membrane protein and putative β-1,3-glucan synthase, while mutations in both Fks1 and its paralog Fks2 (but not Fks3) have been associated with resistance in
C. glabrata
. To further explore their function, regulation, and role in resistance,
C. glabrata
fks
genes were disrupted and subjected to mutational analysis, and their differential regulation was explored. An
fks1
Δ
fks2
Δ double disruptant was not able to be generated; otherwise, all three single and remaining two double disruptants displayed normal growth and echinocandin susceptibility, indicating Fks1-Fks2 redundancy. Selection on echinocandin-containing medium for resistant mutants was dependent on strain background: only
fks1
Δ and
fks1
Δ
fks3
Δ strains consistently yielded mutants exhibiting high-level resistance, all with Fks2 hot spot 1 mutations. Thus, Fks1-Fks2 redundancy attenuates the rate of resistance; further analysis showed that it also attenuates the impact of resistance-conferring mutations. Growth of the
fks1
Δ and, especially,
fks1
Δ
fks3
Δ strains was specifically susceptible to the calcineurin inhibitor FK506. Relatedly, FK506 addition or calcineurin gene
CMP2
disruption specifically reversed Fks2-mediated resistance of laboratory mutants and clinical isolates. RNA analysis suggests that transcriptional control is not the sole mechanism by which calcineurin modulates Fks2 activity.
Full and Broad-Spectrum
In Vivo
Eradication of Catheter-Associated Biofilms Using Gentamicin-EDTA Antibiotic Lock Therapy
Authors: Chauhan Ashwini , Lebeaux David , Ghigo Jean-Marc , Beloin Christophe
Published: October 2012

Biofilms that develop on indwelling devices are a major concern in clinical settings. While removal of colonized devices remains the most frequent strategy for avoiding device-related complications, antibiotic lock therapy constitutes an adjunct therapy for catheter-related infection. However, currently used antibiotic lock solutions are not fully effective against biofilms, thus warranting a search for new antibiotic locks. Metal-binding chelators have emerged as potential adjuvants due to their dual anticoagulant/antibiofilm activities, but studies investigating their efficiency were mainly
in vitro
or else focused on their effects in prevention of infection. To assess the ability of such chelators to eradicate mature biofilms, we used an
in vivo
model of a totally implantable venous access port inserted in rats and colonized by either
Staphylococcus aureus
,
Staphylococcus epidermidis
,
Escherichia coli
, or
Pseudomonas aeruginosa
. We demonstrate that use of tetrasodium EDTA (30 mg/ml) as a supplement to the gentamicin (5 mg/ml) antibiotic lock solution associated with systemic antibiotics completely eradicated Gram-positive and Gram-negative bacterial biofilms developed in totally implantable venous access ports. Gentamicin-EDTA lock was able to eliminate biofilms with a single instillation, thus reducing length of treatment. Moreover, we show that this combination was effective for immunosuppressed rats. Lastly, we demonstrate that a gentamicin-EDTA lock is able to eradicate the biofilm formed by a gentamicin-resistant strain of methicillin-resistant
S. aureus
. This
in vivo
study demonstrates the potential of EDTA as an efficient antibiotic adjuvant to eradicate catheter-associated biofilms of major bacterial pathogens and thus provides a promising new lock solution.
ALMOST RICH WORDS AS MORPHIC IMAGES OF RICH WORDS
Authors: PELANTOVÁ EDITA , STAROSTA ŠTÉPÁN
Published: October 2012

We focus on Θ-rich and almost Θ-rich words over a finite alphabet [Formula: see text], where Θ is an involutive antimorphism over [Formula: see text]. We show that any recurrent almost Θ-rich word u is an image of a recurrent Θ′-rich word under a suitable morphism, where Θ′ is also an involutive antimorphism. Moreover, if the word u is uniformly recurrent, we show that Θ′ can be set to the reversal mapping. We also treat one special case of almost Θ-rich words: we show that every Θ-standard word with seed is an image of an Arnoux-Rauzy word.
PIXE MAPS OF INTRACELLULAR ELEMENT DISTRIBUTION IN CEREBELLAR NEURONS
Authors: KRANDA K. , HAVRANEK V. , PURKARTOVA Z. , VOZEH F. , HAJKOVA L.
Published: October 2012

Neurodegenerative disorders are accompanied by altered compositions of metals that may convey some information about the health and possibly metabolic state of neurons. Here we opted for PIXE technique to perform a spatially-resolved elemental analysis of intracellular space of individual neurons. Primarily, we measured element distribution within Purkinje cells (PC) of normal and Lurcher (Lc/+) mutant mice to detect any anomalies in concentrations of individual elements attributable to cell death. Lc/+ mutant mice provide an excellent animal model for time-course of excitotoxic cell death. PCs, some with autofluorescence, were scanned with a proton beam to record their X-ray emission and RBS spectra and to construct 2D-concentration maps of individual elements. PCs with auto-fluorescence, presumed to be either already dead or moribund, showed elevated concentrations of Cu , Fe , and Zn , when compared to healthy PCs. In conclusion, excitotoxic mode of death, as observed in the moribund PCs of Lc/+ cerebellum, may activate enzymatic processes, manifested as increased intracellular concentrations of Cu and Zn that are possibly constituents of some metalloenzyme complexes.
COHERENT AND INCOHERENT CONTENTS OF CORRELATIONS
Authors: MODI KAVAN , GU MILE
Published: October 2012

We examine bipartite and multipartite correlations within the construct of unitary orbits. We show that the set of product states is a very small subset of set of all possible states, while all unitary orbits contain classically correlated states. Using this we give meaning to degeneration of quantum correlations due to a unitary interactions, which we call coherent correlations. The remaining classical correlations are called incoherent correlations and quantified in terms of the distance of the joint probability distributions to its marginals. Finally, we look at how entanglement looks in this picture for the two-qubit case.
LATTICES OF QUASI-EQUATIONAL THEORIES AS CONGRUENCE LATTICES OF SEMILATTICES WITH OPERATORS: PART II
Authors: ADARICHEVA KIRA , NATION J. B.
Published: October 2012

Part I proved that for every quasivariety 𝒦 of structures (which may have both operations and relations) there is a semilattice S with operators such that the lattice of quasi-equational theories of 𝒦 (the dual of the lattice of sub-quasivarieties of 𝒦) is isomorphic to Con(S, +, 0, 𝒡). It is known that if S is a join semilattice with 0 (and no operators), then there is a quasivariety 𝒬 such that the lattice of theories of 𝒬 is isomorphic to Con(S, +, 0). We prove that if S is a semilattice having both 0 and 1 with a group 𝒢 of operators acting on S, and each operator in 𝒢 fixes both 0 and 1, then there is a quasivariety 𝒲 such that the lattice of theories of 𝒲 is isomorphic to Con(S, +, 0, 𝒢).
ON CERTAIN PAIRS OF NON-ENGEL ELEMENTS IN FINITE GROUPS
Authors: QUEK S. G. , WONG K. B. , WONG P. C.
Published: October 2012

Let G be a group and h, g ∈ G. The 2-tuple (h, g) is said to be an n-Engel pair if h = [h,n g] and g = [g,n h]. In this paper, we will study the subgroup generated by the n-Engel pair under certain conditions.
TUNING THE PRECISION OF PREDICTORS TO REDUCE OVERESTIMATION OF PROTEIN DISORDER OVER LARGE DATASETS
Authors: DEIANA ANTONIO , GIANSANTI ANDREA
Published: October 2012

This is a study on the precision of four known protein disorder predictors, ranked among the best-performing ones: DISOPRED2, PONDR VSL2B, IUPred and ESpritz. We address here the problem of a systematic overestimation of the number of disordered proteins recognized through the use of these predictors, considered as a standard. Some of these predictors, used with their default setting, have a low precision, implying a tendency to overestimate the occurrence of disordered proteins in genome-wide surveys. Moreover, different predictors often disagree on the evaluation of individual proteins. To cope with this problem and in order to propose a simple procedure that enhances precision based on precision-recall curves, we re-tuned the discriminative thresholds of the predictors by training and cross-validating their performance on a cured dataset. After re-tuning, both the disagreement among predictors and the tendency to overestimate the occurrence of disordered proteins are reduced. This is shown in a dedicated study over the human proteome and a set of cancer-related human proteins, with no a priori disorder annotation. Simple quantitative estimates suggest that the occurrence of disorder among cancer-related proteins and other similar large-scale surveys has been overestimated in the past.
Rock magnetic properties of drill cutting from a hydrocarbon exploratory well and their relationship to hydrocarbon presence and petrophysical properties
Authors: Mena M. , Walther A. M.
Published: October 2012

The Golfo San Jorge Basin is one of the most important hydrocarbon-producing basins in Argentina. A study of magnetic properties performed on drill cutting from an oil well drilled in this basin was carried out. The cutting samples, taken from an interval of about 400 m thickness, correspond to the upper units of the Pozo D-129 Formation, the main source rock of the basin. Magnetic susceptibility measurements were made and rock-magnetism studies were conducted. Concentration indices of the different magnetic species determined were calculated based on isothermal remanent magnetization acquisition curves. A correlation analysis among magnetic properties, hydrocarbon content and well logs (sonic, neutron, density, induction, resistivity and photoelectric factor) was performed. Several kinds of significant correlations were found: a positive correlation between susceptibility and relative hydrocarbon content; a positive correlation between magnetic properties and porosities (especially good with the neutron log porosity); and a negative correlation between the concentration indices of some magnetic species (magnetite and pyrrhotite) and resistivity. Pyrrhotite could be directly related to the presence or migration of hydrocarbons through the porous units.

The qualitative correlations between magnetic data and key petrophysical parameters such as porosity, along with the association of magnetic mineralogy to hydrocarbon presence or migration, suggest the potential usefulness of these techniques for subsurface exploration.
INVISIOS
Authors: Arora Divya , Aaraj Najwa , Raghunathan Anand , Jha Niraj K.
Published: October 2012

Many information security attacks exploit vulnerabilities in “trusted” and privileged software executing on the system, such as the operating system (OS). On the other hand, most security mechanisms provide no immunity to security-critical user applications if vulnerabilities are present in the underlying OS. While technologies have been proposed that facilitate isolation of security-critical software, they require either significant computational resources and are hence not applicable to many resource-constrained embedded systems, or necessitate extensive redesign of the underlying processors and hardware.

In this work, we propose INVISIOS: a lightweight, minimally intrusive hardware-software architecture to make the execution of security-critical software invisible to the OS, and hence protected from its vulnerabilities. The INVISIOS software architecture encapsulates the security-critical software into a self-contained software module. While this module is part of the kernel and is run with kernel-level privileges, its code, data, and execution are transparent to and protected from the rest of the kernel. The INVISIOS hardware architecture consists of simple add-on hardware components that are responsible for bootstrapping the secure core, ensuring that it is exercised by applications in only permitted ways, and enforcing the isolation of its code and data. We implemented INVISIOS by enhancing a full-system emulator and Linux to model the proposed software and hardware enhancements, and applied it to protect a commercial cryptographic library. Our experiments demonstrate that INVISIOS is capable of facilitating secure execution at very small overheads, making it suitable for resource-constrained embedded systems and systems-on-chip.
Scheduling and Optimization of Fault-Tolerant Embedded Systems with Transparency/Performance Trade-Offs
Authors: Izosimov Viacheslav , Pop Paul , Eles Petru , Peng Zebo
Published: October 2012

In this article, we propose a strategy for the synthesis of fault-tolerant schedules and for the mapping of fault-tolerant applications. Our techniques handle transparency/performance trade-offs and use the fault-occurrence information to reduce the overhead due to fault tolerance. Processes and messages are statically scheduled, and we use process reexecution for recovering from multiple transient faults. We propose a fine-grained transparent recovery, where the property of transparency can be selectively applied to processes and messages. Transparency hides the recovery actions in a selected part of the application so that they do not affect the schedule of other processes and messages. While leading to longer schedules, transparent recovery has the advantage of both improved debuggability and less memory needed to store the fault-tolerant schedules.
Power Analysis Attack Resistance Engineering by Dynamic Voltage and Frequency Scaling
Authors: Yang Shengqi , Gupta Pallav , Wolf Marilyn , Serpanos Dimitrios , Narayanan Vijaykrishnan , Xie Yuan
Published: October 2012

This article proposes a novel approach to cryptosystem design to prevent power analysis attacks. Such attacks infer program behavior by continuously monitoring the power supply current going into the processor core. They form an important class of security attacks. Our approach is based on dynamic voltage and frequency scaling (DVFS), which hides processor state to make it harder for an attacker to gain access to a secure system. Three designs are studied to test the efficacy of the DVFS method against power analysis attacks. The advanced realization of our cryptosystem is presented which achieves enough high power and time trace entropies to block various kinds of power analysis attacks in the DES algorithm. We observed 27% energy reduction and 16% time overhead in these algorithms. Finally, DVFS hardness analysis is presented.
On Heuristic Solutions to the Simple Offset Assignment Problem in Address-Code Optimization
Authors: Shokry Hesham , El-Boghdadi Hatem M.
Published: October 2012

The increasing demand for more functionality in embedded systems applications nowadays requires efficient generation of compact code for embedded DSP processors. Because such processors have highly irregular data-paths, compilers targeting those processors are challenged with the automatic generation of optimized code with competent quality comparable to hand-crafted code. A major issue in code-generation is to optimize the placement of program variables in ROM relative to each other so as to reduce the overhead instructions dedicated for address computations. Modern DSP processors are typically shipped with a feature called Address Generation Unit (AGU) that provides efficient address-generation instructions for accessing program variables. Compilers targeting those processors are expected to exploit the AGU to optimize variables assignment. This article focuses on one of the basic offset-assignment problems; the Simple Offset Assignment (SOA) problem, where the AGU has only one Address Register and no Modify Registers. The notion of Tie-Break Function, TBF, introduced by Leupers and Marwedel [1996], has been used to guide the placement of variables in memory.

In this article, we introduce a more effective form of the TBF; the Effective Tie-Breaking Function, ETBF, and show that the ETBF is better at guiding the variables placement process. Underpinning ETBF is the fact that program variables are placed in memory in sequence, with each variable having only two neighbors. We applied our technique to randomly generated graphs as well as to real-world code from the OffsetStone testbench [2010]).

In previous work [Ali et al. 2008], our technique showed up to 7% reduction in overhead when applied to randomly-generated problem instances. We report in this article on a further experiment of our technique on real-code from the Offsetstone testbench. Despite the substantial improvement our technique has achieved when applied to random problem instances, we found that it shows slight overhead reduction when applied to real-world instances in OffsetStone, which agrees with similar existing experiments. We analyze these results and show that the ETBF defaults to TBF.
Heterogeneity playing key role
Authors: Wang Yufeng , Nakao Akihiro , Vasilakos Athanasios V.
Published: October 2012

Heterogeneities (heterogeneous characteristics) are intrinsic in dynamic and autonomous networks, and may be caused by the following factors: finite nodes, structured network graph, mutation of node's strategy and topological view, and dynamic linking, and so on. However, few works systematically investigate the effect of the intrinsic heterogeneities on the evolutionary dynamics of incentive mechanisms in autonomous networks. In this article, we thoroughly discuss this interesting problem. Specifically, this article respectively models the pairwise interaction between peers as PD (prisoner's dilemma)-like game and multiple peers' interactions as public-goods game, proposes a general analytical framework for dynamics in evolutionary game theory (EGT)-based incentive mechanisms, and draws the following conclusions. First, for explicit incentive mechanisms, due to heterogeneity, it is impossible to get the static equilibrium of absolutely-full-cooperation (or state that provides service to the networks—so-called reciprocation), but, on the other hand, heterogeneity can facilitate reciprocation evolution, and drive the whole system into almost-full-reciprocation state, that is, most of the system time would be occupied by the full reciprocation state. Second, even without any explicit incentive mechanisms, simultaneous coevolution between dynamic linking and peers' rational strategies can not only facilitate the cooperation evolution, but drive the network structure into the desirable small-world structure. The philosophical implication of our work is that simplicity and homogeneity are too idealized for incentive mechanisms in autonomous networks—diversity and heterogeneity are intrinsic for any incentive mechanism that is compatible with the essence of our real society. Diversity is everywhere.
Combining recency of information with selective random and a victim cache in last-level caches
Authors: Valero Alejandro , Sahuquillo Julio , Petit Salvador , López Pedro , Duato José
Published: October 2012

Memory latency has become an important performance bottleneck in current microprocessors. This problem aggravates as the number of cores sharing the same memory controller increases. To palliate this problem, a common solution is to implement cache hierarchies with large or huge Last-Level Cache (LLC) organizations.

LLC memories are implemented with a high number of ways (e.g., 16) to reduce conflict misses. Typically, caches have implemented the LRU algorithm to exploit temporal locality, but its performance goes away from the optimal as the number of ways increases. In addition, the implementation of a strict LRU algorithm is costly in terms of area and power.

This article focuses on a family of low-cost replacement strategies, whose implementation scales with the number of ways while maintaining the performance. The proposed strategies track the accessing order for just a few blocks, which cannot be replaced. The victim is randomly selected among those blocks exhibiting poor locality. Although, in general, the random policy helps improving the performance, in some applications the scheme fails with respect to the LRU policy leading to performance degradation. This drawback can be overcome by the addition of a small victim cache of the large LLC.

Experimental results show that, using the best version of the family without victim cache, MPKI reduction falls in between 10% and 11% compared to a set of the most representative state-of-the-art algorithms, whereas the reduction grows up to 22% with respect to LRU. The proposal with victim cache achieves speedup improvements, on average, by 4% compared to LRU. In addition, it reduces dynamic energy, on average, up to 8%. Finally, compared to the studied algorithms, hardware complexity is largely reduced by the baseline algorithm of the family.
Dynamic QoS management for chip multiprocessors
Authors: Li Bin , Peh Li-Shiuan , Zhao Li , Iyer Ravi
Published: October 2012

With the continuing scaling of semiconductor technologies, chip multiprocessor (CMP) has become the de facto design for modern high performance computer architectures. It is expected that more and more applications with diverse requirements will run simultaneously on the CMP platform. However, this will exert contention on shared resources such as the last level cache, network-on-chip bandwidth and off-chip memory bandwidth, thus affecting the performance and quality-of-service (QoS) significantly. In this environment, efficient resource sharing and a guarantee of a certain level of performance is highly desirable. Researchers have proposed different frameworks for providing QoS. Most of these frameworks focus on individual resource for QoS management. Coordinated management of multiple QoS-aware shared resources at runtime remains an open problem. Recently, there has been work that proposed a class-of-serviced based framework to jointly managing cache, NoC and memory resources simultaneously. However, the work allocates shared resources
statically
at the beginning of application runtime, and do not dynamically track, manage and share shared resources across applications. In this article, we address this limitation by proposing dynamic resource management policies that monitor the resource usage of applications at runtime, then steals resources from the high-priority applications for lower-priority ones. The goal is to maintain the targeted level of performance for high-priority applications while improving the performance of lower-priority applications. We use a PI (Proportional-Integral gain) feedback controller based technique to maintain stability in our framework. Our evaluation results show that our policy can improve performance for lower-priority applications significantly while maintaining the performance for high-priority application, thus demonstrating the effectiveness of our dynamic QoS resource management policy.
Say Anything
Authors: Swanson Reid , Gordon Andrew S.
Published: October 2012

We describe Say Anything, a new interactive storytelling system that collaboratively writes textual narratives with human users. Unlike previous attempts, this interactive storytelling system places no restrictions on the content or direction of the user’s contribution to the emerging storyline. In response to these contributions, the computer continues the storyline with narration that is both coherent and entertaining. This capacity for open-domain interactive storytelling is enabled by an extremely large repository of nonfiction personal stories, which is used as a knowledge base in a case-based reasoning architecture. In this article, we describe the three main components of our case-based reasoning approach: a million-item corpus of personal stories mined from internet weblogs, a case retrieval strategy that is optimized for narrative coherence, and an adaptation strategy that ensures that repurposed sentences from the case base are appropriate for the user’s emerging fiction. We describe a series of evaluations of the system’s ability to produce coherent and entertaining stories, and we compare these narratives with single-author stories posted to internet weblogs.
Aberrant Activation of Heat Shock Protein 60/65 Reactive T Cells in Patients with Behcet’s Disease
Authors: Shimizu Jun , Izumi Tomoko , Suzuki Noboru
Published: October 2012

Behcet’s disease (BD) is a multisystemic inflammatory disease and is characterized by recurrent attacks on eyes, brain, skin, and gut. There is evidence that skewed T-cell responses contributed to its pathophysiology in patients with BD. We found that heat shock proteins (HSPs) reactive T cells were prevalent in patients with BD. Here, we summarize current findings on HSP reactive T cells and their contribution to the pathogenesis in patients with BD.
Osteoporotic Characteristics Persist in the Spine of Ovariectomized Sheep after Withdrawal of Corticosteroid Administration
Authors: Zarrinkalam Mohammad-Reza , Schultz Christopher G. , Parkinson Ian H. , Moore Robert J.
Published: October 2012

A validated ovine model of osteoporosis achieves severe bone loss in a relatively short period. This study investigated if osteoporotic features persist in this model after cessation of corticosteroid administration.Methods.Osteoporosis was induced in nine ewes by chronic corticosteroid injection, ovariectomy, and low calcium diet. Six ewes were used as controls. Bone mineral density (BMD) of the lumbar spine (LS) and body weight were assessed at regular intervals. After five months, corticosteroid treatment was withdrawn systematically over one month. Three months later, all animals were euthanised, and the LS was collected for histomorphometric analysis.Results.BMD in the LS of osteoporotic sheep was 25% lower than control sheep. Body weight of osteoporotic sheep was reduced in the first month of the corticosteroid withdrawal period but returned to baseline level thereafter. Trabecular bone volume of LS in osteoporotic sheep was 27% lower than controls and showed a heterogeneous structure.Conclusions.Osteoporotic characteristics remain in the vertebra after ceasing corticosteroid administration providing an opportunity to evaluate potential systemic or local treatmentsin vivounder realistic physiological conditions. The microstructural arrangement of vertebral trabecular bone in sheep is similar to humans demonstrating further relevance of this model for preclinical investigations.
Practically Efficient Blind Speech Separation Using Frequency Band Selection Based on Magnitude Squared Coherence and a Small Dodecahedral Microphone Array
Authors: Kondo Kazunobu , Mizuno Yusuke , Nishino Takanori , Takeda Kazuya
Published: October 2012

Small agglomerative microphone array systems have been proposed for use with speech communication and recognition systems. Blind source separation methods based on frequency domain independent component analysis have shown significant separation performance, and the microphone arrays are small enough to make them portable. However, the level of computational complexity involved is very high because the conventional signal collection and processing method uses 60 microphones. In this paper, we propose a band selection method based on magnitude squared coherence. Frequency bands are selected based on the spatial and geometric characteristics of the microphone array device which is strongly related to the dodecahedral shape, and the selected bands are nonuniformly spaced. The estimated reduction in the computational complexity is 90% with a 68% reduction in the number of frequency bands. Separation performance achieved during our experimental evaluation was 7.45 (dB) (signal‐to‐noise ratio) and 2.30 (dB) (cepstral distortion). These results show improvement in performance compared to the use of uniformly spaced frequency band.
Elevated Serum Levels of Homocysteine as an Early Prognostic Factor of Psychiatric Disorders in Children and Adolescents
Authors: Kevere Laura , Purvina Santa , Bauze Daiga , Zeibarts Marcis , Andrezina Raisa , Rizevs Arnis , Jelisejevs Sergejs , Piekuse Linda , Kreile Madara , Purvins Indulis
Published: October 2012

Background and Goal. The aim was to examine the serum levels of homocysteine (Hcy) and their associations with the methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism in patients with schizophrenia and mood disorders as well as controls.Materials and Methods. There were 198 patients: 82 with schizophrenia spectrum disorders, 22 with mood disorders, and 94 controls. The level of Hcy was determined by an isocratic high-performance liquid chromatography system.MTHFRC677T polymorphism was analysed using the restriction fragment length polymorphism-polymerase chain reaction method.Results. The average level of Hcy was11.94±5.6 μmol/L for patients with schizophrenia,11.65±3.3 μmol/L for patients with affective disorders, versus6.80±2.93 μmol/L in a control. The highest level of Hcy has been observed in patients with episodic-recurrent course of schizophrenia (11.30±7.74 μmol/L), paranoid schizophrenia continuous (12.76±5.25 μmol/L), and in patients with affective disorders (11.65±3.26 μmol/L). An association between theMTHFRgene C677T polymorphism and Hcy level was found by linear regression analysis (r=1.41,P=0.029).Conclusions. The data indicate a link between Hcy levels and schizophrenia and mood disorders. No associations between the level of Hcy in patients with schizophrenia and mood disorders and theMTHFRC677T polymorphism were found.
On the Convergence of Multistep Iteration for Uniformly Continuous Φ‐Hemicontractive Mappings
Authors: Xue Zhiqun , Rafiq Arif , Zhou Haiyun
Published: October 2012

It is shown that the convergence of the multistep iterative process with errors is obtained for uniformly continuous Φ‐hemicontractive mappings in real Banach spaces. We also revise the problems of C. E. Chidume and C. O. Chidume (2005).
Factors Influencing the Outcome of Patients with Incidental Papillary Thyroid Microcarcinoma
Authors: Mantinan Beatriz , Rego-Iraeta Antonia , Larrañaga Alejandra , Fluiters Enrique , Sánchez-Sobrino Paula , Garcia-Mayor Ricardo V.
Published: October 2012

Objective. To analyze some factors that could influence the outcome of patients with PTMC.Material and Methods. This is a longitudinal observational study. All patients diagnosed and treated for papillary thyroid microcarcinoma at the University Hospital of Vigo, between January 1994 and December 2003, were included in the present study. Demographic characteristics, tumour characteristics, TNM stage, rate of recurrence, and treatment with131I were the study variables.Results. Ninety-one patients (75 females) with an average age of years, range 19–81, were studied. Initial tumour staging was T1 in 90 patients and T4a in 1 case. Initial lymph node involvement was present in 4 cases (4.4%). We only found one case with distant metastases at diagnosis. Postsurgical evaluation of thyroid specimens revealed that 28 (30.7%) tumours were multifocal. The average size of the tumour was  cm, range 0.1–1. Univariate analysis reveals a statistically significant association between tumour multifocality and postsurgical131I therapy with the recurrence rate. In the multivariate analysis only multifocality (, HR 5.7) was a significant risk factor for the recurrence rate.Conclusions. Our results indicate that tumour multifocality is an independent predictor of relapse but neither the tumour size nor postsurgical131I therapy.