bluuebunny/crossref_metadata_2025 huggingface dataset:
Time domain simulation and sound synthesis for the snare drum
Authors: Bilbao Stefan
Published: January 2012

The snare drum is a complex system, relying on the interaction of multiple components: the drumheads, or membranes, a set of snares, the surrounding acoustic field and an internal cavity. Because these components are multidimensional, and due to a strong distributed non-linearity (the snare interaction), many techniques used frequently in physical modeling synthesis applications, such as digital waveguides and modal methods are difficult to apply. In this article, finite difference time domain techniques are applied to a full 3D system, and various features of interest, such as the coupling between membranes, and the interaction between the membranes and the snares, are examined in detail. Also discussed are various numerical features, such as spurious splitting of degenerate modes and bandwidth limitation, and estimates of computational complexity are provided. Sound examples are presented.
Experimentally based description of harp plucking
Authors: Chadefaux Delphine , Le Carrou Jean-Loïc , Fabre Benoît , Daudet Laurent
Published: January 2012

This paper describes an experimental study of string plucking for the classical harp. Its goal is to characterize the playing parameters that play the most important roles in expressivity, and in the way harp players recognize each other, even on isolated notes—what we call the “acoustical signature” of each player. We have designed a specific experimental setup using a high-speed camera that tracks some markers on the fingers and on the string. This provides accurate three-dimensional positioning of the finger and of the string throughout the plucking action, in different musical contexts. From measurements of ten harp players, combined with measurements of the soundboard vibrations, we extract a set of parameters that finely control the initial conditions of the string’s free oscillations. Results indicate that these initial conditions are typically a complex mix of displacement and velocity, with additional rotation. Although remarkably reproducible by a single player—and the more so for professional players—we observe that some of these control parameters vary significantly from one player to another.
Lateralization produced by interaural temporal and intensitive disparities of high-frequency, raised-sine stimuli: Data and modeling
Authors: Bernstein Leslie R. , Trahiotis Constantine
Published: January 2012

An acoustic pointing task was used to measure extents of laterality produced by combinations of ongoing envelope-based interaural temporal disparities (ITDs) and interaural intensitive disparities (IIDs) of 4-kHz-centered raised-sine stimuli [Bernstein and Trahiotis, J. Acoust. Soc. Am. 125, 3234–3242 (2009),] while varying, parametrically, their peakedness, depth of modulation, and frequency of modulation. The study was designed to assess whether IIDs act as “weights” within the putative “binaural display” at high spectral frequencies (where the envelopes convey ITD-information) as appears to be the case at low spectral frequencies (where the waveforms, i.e., fine-structure and envelopes, convey ITD-information). The data indicate that envelope-based IIDs do principally act as weights and that they appear to exert their influence on lateral position independently of the influence of ITDs. Quantitative analyses revealed that an augmented form of the cross-correlation-based “position-variable” model of Stern and Shear [J. Acoust. Soc. Am. 100, 2278–2288 (1996)] accounted for 94% of the variance in the data. This success notwithstanding, for a small subset of the data, predictions could be improved by assuming that the listeners utilized information within auditory filters having center frequencies above 4 kHz.
Experimental investigation of the effects of the acoustical conditions in a simulated classroom on speech recognition and learning in children
Authors: Valente Daniel L. , Plevinsky Hallie M. , Franco John M. , Heinrichs-Graham Elizabeth C. , Lewis Dawna E.
Published: January 2012

The potential effects of acoustical environment on speech understanding are especially important as children enter school where students’ ability to hear and understand complex verbal information is critical to learning. However, this ability is compromised because of widely varied and unfavorable classroom acoustics. The extent to which unfavorable classroom acoustics affect children’s performance on longer learning tasks is largely unknown as most research has focused on testing children using words, syllables, or sentences as stimuli. In the current study, a simulated classroom environment was used to measure comprehension performance of two classroom learning activities: a discussion and lecture. Comprehension performance was measured for groups of elementary-aged students in one of four environments with varied reverberation times and background noise levels. The reverberation time was either 0.6 or 1.5 s, and the signal-to-noise level was either +10 or +7 dB. Performance is compared to adult subjects as well as to sentence-recognition in the same condition. Significant differences were seen in comprehension scores as a function of age and condition; both increasing background noise and reverberation degraded performance in comprehension tasks compared to minimal differences in measures of sentence-recognition.
Subjective and objective speech intelligibility investigations in primary school classrooms
Authors: Astolfi Arianna , Bottalico Pasquale , Barbato Giulio
Published: January 2012

This work concerns speech intelligibility tests and measurements in three primary schools in Italy, one of which was conducted before and after an acoustical treatment. Speech intelligibility scores (IS) with different reverberation times (RT) and types of noise were obtained using diagnostic rhyme tests on 983 pupils from grades 2–5 (nominally 7–10 year olds), and these scores were then correlated with the Speech Transmission Index (STI). The grade 2 pupils understood fewer words in the lower STI range than the pupils in the higher grades, whereas an IS of ∼97% was achieved by all the grades with a STI of 0.9. In the presence of traffic noise, which resulted the most interfering noise, a decrease in RT from 1.6 to 0.4 s determined an IS increase on equal A-weighted speech-to-noise level difference, S/N(A), which varied from 13% to 6%, over the S/N(A) range of −15 to +6 dB, respectively. In the case of babble noise, whose source was located in the middle of the classroom, the same decrease in reverberation time leads to a negligible variation in IS over a similar S/N(A) range.
The direct and indirect roles of fundamental frequency in vowel perception
Authors: Barreda Santiago , Nearey Terrance M.
Published: January 2012

Several experiments have found that changing the intrinsic f0 of a vowel can have an effect on perceived vowel quality. It has been suggested that these shifts may occur because f0 is involved in the specification of vowel quality in the same way as the formant frequencies. Another possibility is that f0 affects vowel quality indirectly, by changing a listener’s assumptions about characteristics of a speaker who is likely to have uttered the vowel. In the experiment outlined here, participants were asked to listen to vowels differing in terms of f0 and their formant frequencies and report vowel quality and the apparent speaker’s gender and size on a trial-by-trial basis. The results presented here suggest that f0 affects vowel quality mainly indirectly via its effects on the apparent-speaker characteristics; however, f0 may also have some residual direct effects on vowel quality. Furthermore, the formant frequencies were also found to have significant indirect effects on vowel quality by way of their strong influence on the apparent speaker.
Echolocation with bat buzz emissions: Model and biomimetic sonar for elevation estimation
Authors: Kuc Roman
Published: January 2012

Just prior to capture the Buzz II emissions of some mouth-emitting bats, such as Eptesicus fuscus, are observed to exhibit spectra having multiple peaks. This paper proposes an echolocation strategy that uses such spectra with energy concentrated in specific frequency bands for determining target elevation. A biomimetic sonar was implemented to produce a tri-modal spectrum by driving a speaker with a signal rich in harmonics. The emission magnitudes at these harmonic frequencies measured as a function of elevation in the zero-azimuth plane form distinct beams. A template was formed from the ratio of the first harmonic and fundamental magnitudes to determine elevation. The elevation estimator exhibited a sub-degree accuracy (SD=0.4∘) over a 20° interval centered at the elevation at which these two beams intersect in the zero-azimuth plane. Spectral cues from –40° to +10° elevation allow a qualitative non-linear control of sonar orientation to drive the target to the beam-intersection point where quantitative elevation estimates are available.
Changing only the probability that spoken words will be distorted changes how they are recognized
Authors: McQueen James M. , Huettig Falk
Published: January 2012

An eye-tracking experiment examined contextual flexibility in speech processing in response to distortions in spoken input. Dutch participants heard Dutch sentences containing critical words and saw four-picture displays. The name of one picture either had the same onset phonemes as the critical word or had a different first phoneme and rhymed. Participants fixated on onset-overlap more than rhyme-overlap pictures, but this tendency varied with speech quality. Relative to a baseline with noise-free sentences, participants looked less at onset-overlap and more at rhyme-overlap pictures when phonemes in the sentences (but not in the critical words) were replaced by noises like those heard on a badly tuned AM radio. The position of the noises (word-initial or word-medial) had no effect. Noises elsewhere in the sentences apparently made evidence about the critical word less reliable: Listeners became less confident of having heard the onset-overlap name but also less sure of having not heard the rhyme-overlap name. The same acoustic information has different effects on spoken-word recognition as the probability of distortion changes.
Underwater ambient noise on the Chukchi Sea continental slope from 2006–2009
Authors: Roth Ethan H , Hildebrand John A. , Wiggins Sean M. , Ross Donald
Published: January 2012

From September 2006 to June 2009, an autonomous acoustic recorder measured ambient noise north of Barrow, Alaska on the continental slope at 235 m depth, between the Chukchi and Beaufort Seas. Mean monthly spectrum levels, selected to exclude impulsive events, show that months with open-water had the highest noise levels (80–83 dB re: 1 μPa2/Hz at 20–50 Hz), months with ice coverage had lower spectral levels (70 dB at 50 Hz), and months with both ice cover and low wind speeds had the lowest noise levels (65 dB at 50 Hz). During ice covered periods in winter-spring there was significant transient energy between 10 and 100 Hz from ice fracture events. During ice covered periods in late spring there were significantly fewer transient events. Ambient noise increased with wind speed by ∼1 dB/m/s for relatively open-water (0%–25% ice cover) and by ∼0.5 dB/m/s for nearly complete ice cover (> 75%). In September and early October for all years, mean noise levels were elevated by 2–8 dB due to the presence of seismic surveys in the Chukchi and Beaufort Seas.
Acoustic streaming field structure. Part II. Examples that include boundary-driven flow
Authors: Bradley Charles
Published: January 2012

In this paper three simple acoustic streaming problems are presented and solved. The purpose of the paper is to demonstrate the use of a previously published streaming model by Bradley [J. Acoust. Soc. Am. 100(3), 1399–1408 (1996)] and illustrate, with concrete examples, some of the features of streaming flows that were predicted by the general model. In particular, the problems are intended to demonstrate cases in which the streaming field boundary condition at the face of the radiator has a nontrivial lateral dc velocity component. Such a boundary condition drives a steady solenoidal flow just like a laterally translating boundary drives Couette flow.
Comparing the effects of reverberation and of noise on speech recognition in simulated electric-acoustic listening
Authors: Helms Tillery Kate , Brown Christopher A. , Bacon Sid P.
Published: January 2012

Cochlear implant users report difficulty understanding speech in both noisy and reverberant environments. Electric-acoustic stimulation (EAS) is known to improve speech intelligibility in noise. However, little is known about the potential benefits of EAS in reverberation, or about how such benefits relate to those observed in noise. The present study used EAS simulations to examine these questions. Sentences were convolved with impulse responses from a model of a room whose estimated reverberation times were varied from 0 to 1 sec. These reverberated stimuli were then vocoded to simulate electric stimulation, or presented as a combination of vocoder plus low-pass filtered speech to simulate EAS. Monaural sentence recognition scores were measured in two conditions: reverberated speech and speech in a reverberated noise. The long-term spectrum and amplitude modulations of the noise were equated to the reverberant energy, allowing a comparison of the effects of the interferer (speech vs noise). Results indicate that, at least in simulation, (1) EAS provides significant benefit in reverberation; (2) the benefits of EAS in reverberation may be underestimated by those in a comparable noise; and (3) the EAS benefit in reverberation likely arises from partially preserved cues in this background accessible via the low-frequency acoustic component.
A physical approach to the automated classification of clinical percussion sounds
Authors: Pantea M. A. , Maev R. Gr. , Malyarenko E. V. , Baylor A. E.
Published: January 2012

Chest percussion is a traditional technique used for the physical examination of pulmonary injuries and diseases. It is a method of tapping body parts with fingers or small instruments to evaluate the size, consistency, borders, and presence of fluid/air in the lungs and abdomen. Percussion has been successfully used for the diagnosis of such potentially lethal conditions as traumatic and tension pneumothorax. This technique, however, has certain shortcomings, including limitations of the human ear and the subjectivity of the administrator, that lead to overall low sensitivity. Automation of the method by using a standardized percussion source and computerized classification of digitized signals would remove the subjective factor and other limitations of the technique. It would also enable rapid on-site diagnostics of pulmonary traumas when thorough clinical examination is impossible. This paper lays the groundwork for an objective signal classification approach based on a general physical model of a damped harmonic oscillator. Using this concept, critical parameters that effectively subdivide percussion signals into three main groups, historically known as “tympanic,” “resonant,” and “dull,” are identified, opening the possibility for automated diagnostics of air/liquid inclusions in the thorax and abdomen. The key role of damping in forming the character of the percussion signal is investigated using a 3D thorax phantom. The contribution of the abdominal component into the complex multimode spectrum of chest percussion signals is demonstrated.
Managing the distinctiveness of phonemic nasal vowels: Articulatory evidence from Hindi
Authors: Shosted Ryan , Carignan Christopher , Rong Panying
Published: January 2012

There is increasing evidence that fine articulatory adjustments are made by speakers to reinforce and sometimes counteract the acoustic consequences of nasality. However, it is difficult to attribute the acoustic changes in nasal vowel spectra to either oral cavity configuration or to velopharyngeal opening (VPO). This paper takes the position that it is possible to disambiguate the effects of VPO and oropharyngeal configuration on the acoustic output of the vocal tract by studying the position and movement of the tongue and lips during the production of oral and nasal vowels. This paper uses simultaneously collected articulatory, acoustic, and nasal airflow data during the production of all oral and phonemically nasal vowels in Hindi (four speakers) to understand the consequences of the movements of oral articulators on the spectra of nasal vowels. For Hindi nasal vowels, the tongue body is generally lowered for back vowels, fronted for low vowels, and raised for front vowels (with respect to their oral congeners). These movements are generally supported by accompanying changes in the vowel spectra. In Hindi, the lowering of back nasal vowels may have originally served to enhance the acoustic salience of nasality, but has since engendered a nasal vowel chain shift.
Time-frequency analysis of the bistatic acoustic scattering from a spherical elastic shell
Authors: Anderson Shaun D. , Sabra Karim G. , Zakharia Manell E. , Sessarego Jean-Pierre
Published: January 2012

The development of low-frequency sonar systems, using, for instance, a network of autonomous systems in unmanned vehicles, provides a practical means for bistatic measurements (i.e., when the source and receiver are widely separated) allowing for multiple viewpoints of the target of interest. Time-frequency analysis, in particular, Wigner–Ville analysis, takes advantage of the evolution time dependent aspect of the echo spectrum to differentiate a man-made target, such as an elastic spherical shell, from a natural object of the similar shape. A key energetic feature of fluid-loaded and thin spherical shell is the coincidence pattern, also referred to as the mid-frequency enhancement (MFE), that results from antisymmetric Lamb-waves propagating around the circumference of the shell. This article investigates numerically the bistatic variations of the MFE with respect to the monostatic configuration using the Wigner–Ville analysis. The observed time-frequency shifts of the MFE are modeled using a previously derived quantitative ray theory by Zhang et al. [J. Acoust. Soc. Am. 91, 1862–1874 (1993)] for spherical shell’s scattering. Additionally, the advantage of an optimal array beamformer, based on joint time delays and frequency shifts is illustrated for enhancing the detection of the MFE recorded across a bistatic receiver array when compared to a conventional time-delay beamformer.
GROUND STATES OF A MIXTURE OF TWO SPECIES OF SPIN-1 BOSE GASES WITH INTERSPECIES SPIN EXCHANGE IN A MAGNETIC FIELD
Authors: SHI YU , GE LI
Published: January 2012

We consider a mixture of two species of spin-1 atoms with both interspecies and intraspecies spin exchanges in a weak magnetic field. Under the usual single mode approximation, it can be reduced to a model of coupled giant spins. We find most of its ground states. This is a complicated problem of energy minimization, with three quantum variables under constraints, i.e., the total spin of each species and the total spin of the whole mixture, as well as four parameters, including intraspecies and interspecies spin coupling strengths and the magnetic field. The quantum phase diagram is very rich. Compared with the case without a magnetic field, the ground states are modified by a magnetic field, which also modifies the ground state boundaries or introduces new crossover regimes on the phase diagram. Without interspecies spin coupling, the quantum phase transitions existing in absence of a magnetic field disappear when a magnetic field is applied, which leads to crossover regimes in the phase diagram. Under ferromagnetic interspecies spin coupling, the ground states remain disentangled no matter whether there is a magnetic field. For antiferromagnetic interspecies spin coupling, a magnetic field entangles the ground states in some parameter regimes. When the intraspecies spin couplings are both ferromagnetic, the quantum phase transition between antiferromagnetic and zero interspecies spin couplings survives the magnetic field. When the intraspecies spin couplings are both antiferromagnetic, a magnetic field induces new quantum phase transitions between antiferromagnetic and zero interspecies spin couplings.
GENERALIZED MODEL OF MIGRATION-DRIVEN AGGREGATE GROWTH — ASYMPTOTIC DISTRIBUTIONS, POWER LAWS AND APPARENT FRACTALITY
Authors: GORDIENKO YURI G.
Published: January 2012

The rate equation for exchange-driven aggregation of monomers between clusters of size n by power-law exchange rate (~ nα), where detaching and attaching processes were considered separately, is reduced to Fokker–Planck equation. Its exact solution was found for unbiased aggregation and agreed with asymptotic conclusions of other models. Asymptotic transitions were found from exact solution to Weibull/normal/exponential distribution, and then to power law distribution. Intermediate asymptotic size distributions were found to be functions of exponent α and vary from normal (α = 0) through Weibull (0 < α < 1) to exponential (α =1) ones, that gives the new system for linking these basic statistical distributions. Simulations were performed for the unbiased aggregation model on the basis of the initial rate equation without simplifications used for reduction to Fokker–Planck equation. The exact solution was confirmed, shape and scale parameters of Weibull distribution (for 0 < α < 1) were determined by analysis of cumulative distribution functions and mean cluster sizes, which are of great interest, because they can be measured in experiments and allow to identify details of aggregation kinetics (like α). In practical sense, scaling analysis of evolving series of aggregating cluster distributions can give much more reliable estimations of their parameters than analysis of solitary distributions. It is assumed that some apparent power and fractal laws observed experimentally may be manifestations of such simple migration-driven aggregation kinetics even.
Water-soluble porphyrin-based logic gates
Authors: Li Lili , Cai Peiying , Deng Yuefei , Yang Liutao , He Xuan , Pu Lingsong , Wu Di , Liu Jin , Xiang Haifeng , Zhou Xiangge
Published: January 2012

A series of simple logic gates based on a water-soluble porphyrin molecule, 5,10,15,20-tetrakis-(4-sulfonatophenyl)porphyrin (TPPS4) is designed. Logic operations, including OR, NOR, INHIBIT and AND, have been built by two inputs of acid/base or metal ions (Al3+ and/or Sn4+) and two outputs of UV-vis absorption and fluorescent spectra. An OFF–ON switch triggered by Al3+ ion in vitro is developed based on TPPS4.
Concentration-dependent aggregation of water-soluble phosphorus porphyrin in an aqueous solution
Authors: Matsumoto Jin , Tanimura Shin-ichio , Shiragami Tsutomu , Yasuda Masahide
Published: January 2012

Water-soluble phosphorus tetraphenylporphyrins (1) were prepared by the introduction of axial polyoxaalkyloxo ligands (–O–(CH2CH2O)m–(CH2)n–H) . Bioaffinity of 1 for Saccharomyces cerevisiae was evaluated on the basis of the concentration (B A ) of 1 absorbed into the cells after they were immersed into an aqueous solution of 1 (10 μM). The behavior of 1 in the concentration range from 1 μM to 0.1 mM were estimated by measuring surface tension and absorption spectra and the behavior at a concentration of 1 mM were estimated by NMR spectroscopy. The 1 (m = 2, n = 4; m = 1, 2 and 3, n = 6) with a high B A of 123–171 mM were solved as monomers at 10 μM and could pass through the cell wall to accumulate inside the cell. Once inside the cell, where they reached a concentration of more than 10 μM, they formed aggregates that were unable to escape to the outside of the cell. On the other hand, it was found that 1 (m = 2 and 3, n = 1; m = 2, n = 2), whose B A values were <24 mM, did not form aggregates in the range from 1 μM to 1 mM; this indicated that they easily passed through the cell wall in both directions. In the case of 1 (m = 2 and 3, n = 12), whose B A values were low, passage through the cell wall was not possible because aggregates formed even at <1 μM.
Configuration coverage in the analysis of large-scale system software
Authors: Tartler Reinhard , Lohmann Daniel , Dietrich Christian , Egger Christoph , Sincero Julio
Published: January 2012

System software, especially operating systems, tends to be highly configurable. Like every complex piece of software, a considerable amount of bugs in the implementation has to be expected. In order to improve the general code quality, tools for static analysis provide means to check for source code defects without having to run actual test cases on real hardware. Still, for proper type checking a specific configuration is required so that all header include paths are available and all types are properly resolved.

In order to find as many bugs as possible, usually a "full configuration" is used for the check. However, mainly because of alternative blocks in form of #else-blocks, a single configuration is insufficient to achieve full coverage. In this paper, we present a metric for configuration coverage (CC) and explain the challenges for (properly) calculating it. Furthermore, we present an efficient approach for determining a sufficiently small set of configurations that achieve (nearly) full coverage and evaluate it on a recent Linux kernel version.
SEEP
Authors: Hönig Timo , Eibel Christopher , Kapitza Rüdiger , Schröder-Preikschat Wolfgang
Published: January 2012

In recent years, there has been a rapid evolution of energyaware computing systems (e.g., mobile devices, wireless sensor nodes), as still rising system complexity and increasing user demands make energy a permanently scarce resource. While static and dynamic optimizations for energy-aware execution have been explored massively, writing energyefficient programs in the first place has only received limited attention. This paper proposes SEEP, a framework which exploits symbolic execution and platform-specific energy profiles to provide the basis for
energy-aware programming
. More specifically, the framework provides developers with information about the energy demand of their code at hand, even for the invocation of library functions and in settings with multiple possibly strongly heterogeneous target platforms. This equips developers with the necessary knowledge to take energy demand into account during the task of writing programs.
The meaningful use of big data
Authors: Bizer Christian , Boncz Peter , Brodie Michael L. , Erling Orri
Published: January 2012

Twenty-five Semantic Web and Database researchers met at the 2011 STI Semantic Summit in Riga, Latvia July 6-8, 2011[1] to discuss the opportunities and challenges posed by Big Data for the Semantic Web, Semantic Technologies, and Database communities. The unanimous conclusion was that the greatest shared challenge was not only engineering Big Data, but also doing so meaningfully. The following are four expressions of that challenge from different perspectives.
Evaluating the benefits and feasibility of coordinated medium access in MANETS
Authors: Sobral Marcelo M. , Becker Leandro B.
Published: January 2012

Mobile ad hoc wireless network (MANETs) are characterized by a highly-dynamic topology where neither the duration of links between nodes nor their densities within the network can be foreseing. To better understand the effects of such issues in the medium access we provide a performance evaluation of two distinct MAC protocols. The first is our previously proposed HCT (Hybrid Contention/TDMA) Real-Time MAC protocol, which continuously adapts to topology modifications in order to provide a kind of coordinated medium access. Its performance is compared with a contention-based, non-coordinated CSMA protocol, which is the typical MAC protocol used in MANETs. We analyze both protocols with respect to their ability to deliver messages in a timely manner. More specifically, we compared the ratio of messages delivered within their deadlines and the medium utilization provided by these protocols. Such aspects where analyzed considering mobile networks with different spatial densities and speeds of nodes. This study also addresses the protocols overhead, especially for HCT-MAC. Obtained results show that HCT-MAC appears as a good solution for applications like search-and-rescue, autonomous highway driving (platooning), and multimedia, which require some kind of QoS guarantee in respect to the timely delivery of messages.
Privacy in "the cloud"
Authors: Grodzinsky F. S. , Tavani H. T.
Published: January 2012

The present essay is organized into five main sections. We begin with a few preliminary remarks about "cloud computing," which are developed more fully in a later section. This is followed by a brief overview of the evolution of Helen Nissenbaum's framework of "privacy as contextual integrity." In particular, we examine Nissenbaum's "Decision Heuristic" model, described in her most recent work on privacy (Nissenabum 2010), to see how it enables the contextual-integrity framework to respond to privacy challenges posed by new and emerging technologies. We then apply that heuristic device to questions surrounding one aspect of cloud computing -- viz., "cloud storage" technology. In particular, we focus on current practices affecting Google Docs as an instance of a cloud-storage system.
E-government
Authors: Mishra Alok , Mishra Deepti
Published: January 2012

This paper explores the different dimensions of e-government significant issues -- Challenges, Implementation, and Success Factors. The main objective is to highlight the current research and practice direction in these important areas of e-government. The results were limited to peer-reviewed conference papers and journal articles, published from 2001 up to and including early 2011. The analysis revealed that most research has been done in formulating challenges and barriers, implementation plan, evaluation/assessment and success factors of e-government while studies on knowledge management in e-government, readiness for e-government, e-Gov. process and security/privacy issues could get only limited attention. This indicates the need for future research (quantitative and qualitative) in these areas. Further it also reports a summary of the research in these e-government areas.
Bringing back monad comprehensions
Authors: Giorgidze George , Grust Torsten , Schweinsberg Nils , Weijers Jeroen
Published: January 2012

This paper is about a Glasgow Haskell Compiler (GHC) extension that generalises Haskell's list comprehension notation to monads. The monad comprehension notation implemented by the extension supports generator and filter clauses, as was the case in the Haskell 1.4 standard. In addition, the extension generalises the recently proposed parallel and SQL-like list comprehension notations to monads. The aforementioned generalisations are formally defined in this paper. The extension will be available in GHC 7.2.

This paper gives several instructive examples that we hope will facilitate wide adoption of the extension by the Haskell community. We also argue why the do notation is not always a good fit for monadic libraries and embedded domain-specific languages, especially for those that are based on collection monads. Should the question of how to integrate the extension into the Haskell standard arise, the paper proposes a solution to the problem that led to the removal of the monad comprehension notation from the language standard.
Efficient parallel stencil convolution in Haskell
Authors: Lippmeier Ben , Keller Gabriele
Published: January 2012

Stencil convolution is a fundamental building block of many scientific and image processing algorithms. We present a declarative approach to writing such convolutions in Haskell that is both efficient at runtime and implicitly parallel. To achieve this we extend our prior work on the Repa array library with two new features: partitioned and cursored arrays. Combined with careful management of the interaction between GHC and its back-end code generator LLVM, we achieve performance comparable to the standard OpenCV library.
Stability of an n‐Dimensional Mixed‐Type Additive and Quadratic Functional Equation in Random Normed Spaces
Authors: Lee Yang-Hi , Jung Soon-Mo
Published: January 2012

We investigate the stability problems for the n‐dimensional mixed‐type additive and quadratic functional equation in random normed spaces by applying the fixed point method.
Isolation, Purification, and Characterization of Xylanase Produced by a New Species ofBacillusin Solid State Fermentation
Authors: Kamble Rajashri D. , Jadhav Anandrao R.
Published: January 2012

A thermoalkalophilic new species ofBacillus, similar toBacillus arseniciselenatisDSM 15340, produced extracellular xylanase under solid state fermentation when wheat bran is used as carbon source. The extracellular xylanase was isolated by ammonium sulfate (80%) precipitation and purified using ion exchange chromatography. The molecular weight of xylanase was ~29.8 ;kDa. The optimum temperature and pH for the enzyme activity were 50°C and pH 8.0. The enzyme was active on birchwood xylan and little active onp-nitrophenyl xylopyranoside but not on Avicel, CMC, cellobiose, and starch, showing its absolute substrate specificity. For birchwood xylan, the enzyme gave a Km 5.26 ;mg/mL and Vmax 277.7 ;μmol/min/mg, respectively. In addition, the xylanase was also capable of producing high-quality xylo-oligosaccharides, which indicated its application potential not only in pulp biobleaching processes but also in the nutraceutical industry.
PlasmodiumRiboprotein PfP0 Induces a Deviant Humoral Immune Response in Balb/cMice
Authors: Pathak Sulabha , Rajeshwari K. , Garg Swati , Rajagopal Sudarsan , Patel Kalpesh , Das Bidyut , Pied Sylviane , Ravindran Balachandran , Sharma Shobhona
Published: January 2012

Passive immunization with antibodies to recombinantPlasmodium falciparumP0 riboprotein (rPfP0, 61–316 amino acids) provides protection against malaria. Carboxy-terminal 16 amino acids of the protein (PfP0C0) are conserved and show 69% identity to human and mouse P0. Antibodies to this domain are found in 10–15% of systemic lupus erythematosus patients. We probed the nature of humoral response to PfP0C0 by repeatedly immunizing mice with rPfP0. We failed to raise stable anti-PfP0C0 hybridomas from any of the 21 mice. The average serum anti-PfP0C0 titer remained low (5.1±1.3×104). Pathological changes were observed in the mice after seven boosts. Adsorption with dinitrophenyl hapten revealed that the anti-PfP0C0 response was largely polyreactive. This polyreactivity was distributed across all isotypes. Similar polyreactive responses to PfP0 and PfP0C0 were observed in sera from malaria patients. Our data suggests that PfP0 induces a deviant humoral response, and this may contribute to immune evasion mechanisms of the parasite.
Well‐Posedness for a Class of Strongly Mixed Variational‐Hemivariational Inequalities with Perturbations
Authors: Ceng Lu-Chuan , Wong Ngai-Ching , Yao Jen-Chih
Published: January 2012

The concept of well‐posedness for a minimization problem is
extended to develop the concept of well‐posedness for a class of strongly mixed variational‐hemivariational
inequalities with perturbations which includes as a special case the class of
variational‐hemivariational inequalities with perturbations. We establish some metric characterizations
for the well‐posed strongly mixed variational‐hemivariational inequality and give
some conditions under which the strongly mixed variational‐hemivariational inequality is
strongly well‐posed in the generalized sense. On the other hand, it is also proven that under
some mild conditions there holds the equivalence between the well posedness for a strongly
mixed variational‐hemivariational inequality and the well‐posedness for the corresponding inclusion
problem.
Fluorescence Enhancement Factors on Optical Antennas: Enlarging the Experimental Values without Changing the Antenna Design
Authors: Wenger Jérôme
Published: January 2012

Plasmonic antennas offer promising opportunities to control the emission of quantum objects. As a consequence, the fluorescence enhancement factor is widely used as a figure of merit for a practical antenna realization. However, the fluorescence enhancement factor is not an intrinsic property of the antenna. It critically depends on several parameters, some of which are often disregarded. In this contribution, I explore the influence of the setup collection efficiency, emitter's quantum yield, and excitation intensity. Improperly setting these parameters may significantly alter the enhancement values, leading to potential misinterpretations. The discussion is illustrated by an antenna example of a nanoaperture surrounded by plasmonic corrugations.
Lifetime Cancer Risks in Individuals with Germline PTEN Mutations
Authors: Tan Min-Han , Mester Jessica L. , Ngeow Joanne , Rybicki Lisa A. , Orloff Mohammed S. , Eng Charis
Published: January 2012

Purpose: Age-adjusted cancer incidence and age-related penetrance studies have helped guide cancer risk assessment and management. PTEN hamartoma tumor syndrome (PHTS) is a term encompassing subsets of several clinical syndromes with germline mutations in the PTEN tumor suppressor gene. We conducted the first prospective study to clarify corresponding cancer risks to shed biologic insights on human germline PTEN mutations, and to better inform current surveillance recommendations on the basis of expert opinion.

Experimental Design: A series of 3,399 individuals meeting relaxed International Cowden Consortium PHTS criteria were prospectively recruited; 368 individuals were found to have deleterious germline PTEN mutations. Age-adjusted standardized incidence ratio (SIR) calculations and genotype–phenotype analyses were carried out.

Results: Elevated SIRs were found for carcinomas of the breast [25.4, 95% confidence interval (CI), 19.8–32.0], thyroid (51.1, 38.1–67.1), endometrium (42.9, 28.1–62.8), colorectum (10.3, 5.6–17.4), kidney (30.6, 17.8–49.4), and melanoma (8.5, 4.1–15.6). Estimated lifetime risks were, respectively, 85.2% (95% CI, 71.4%–99.1%), 35.2% (19.7%–50.7%), 28.2% (17.1%–39.3%), 9.0% (3.8%–14.1%), 33.6% (10.4%–56.9%), and 6% (1.6%-9.4%). Promoter mutations were associated with breast cancer, whereas colorectal cancer was associated with nonsense mutations.

Conclusion: Lifetime risks for a variety of cancers, now extending to colorectal cancer, kidney cancer, and melanoma, are increased in patients with PTEN mutations. The genotype–phenotype associations here may provide new insights on PTEN structure and function. We propose a comprehensive approach to surveillance of patients with PTEN mutations. Clin Cancer Res; 18(2); 400–7. ©2012 AACR.
EGFR-Mediated Reactivation of MAPK Signaling Contributes to Insensitivity of BRAF-Mutant Colorectal Cancers to RAF Inhibition with Vemurafenib
Authors: Corcoran Ryan B. , Ebi Hiromichi , Turke Alexa B. , Coffee Erin M. , Nishino Michiya , Cogdill Alexandria P. , Brown Ronald D. , Della Pelle Patricia , Dias-Santagata Dora , Hung Kenneth E. , Flaherty Keith T. , Piris Adriano , Wargo Jennifer A. , Settleman Jeffrey , Mino-Kenudson Mari , Engelman Jeffrey A.
Published: January 2012

BRAF mutations occur in 10% to 15% of colorectal cancers and confer adverse outcome in the metastatic setting. Although RAF inhibitors such as vemurafenib (PLX4032) have proven effective in the treatment of BRAF-mutant melanoma, they are surprisingly ineffective in BRAF-mutant colorectal cancers, and the reason for this disparity remains unclear. Compared with BRAF-mutant melanoma cells, BRAF-mutant colorectal cancer cells were less sensitive to vemurafenib, and phospho-extracellular signal-regulated kinase (P-ERK) suppression was not sustained in response to treatment. Although transient inhibition of P-ERK by vemurafenib was observed in colorectal cancer, rapid ERK reactivation occurred through epidermal growth factor receptor (EGFR)-mediated activation of RAS and CRAF. BRAF-mutant colorectal cancers expressed greater levels of phospho-EGFR than BRAF-mutant melanomas, suggesting that colorectal cancers are specifically poised for EGFR-mediated resistance. Combined RAF and EGFR inhibition blocked reactivation of mitogen-activated protein kinase (MAPK) signaling in BRAF-mutant colorectal cancer cells and markedly improved efficacy in vitro and in vivo. These findings support the evaluation of combined RAF and EGFR inhibition in patients with BRAF-mutant colorectal cancer.

Significance: BRAF valine 600 (V600) mutations occur in 10% to 15% of colorectal cancers, yet these tumors show a surprisingly low clinical response rate (∼5%) to selective RAF inhibitors such as vemurafenib, which have produced dramatic response rates (60%–80%) in melanomas harboring the identical BRAF V600 mutation. We found that EGFR-mediated MAPK pathway reactivation leads to resistance to vemurafenib in BRAF-mutant colorectal cancers and that combined RAF and EGFR inhibition can lead to sustained MAPK pathway suppression and improved efficacy in vitro and in tumor xenografts. Cancer Discovery; 2(3); 227–35. ©2012 AACR.

This article is highlighted in the In This Issue feature, p. 193
Differential Diagnosis in Alzheimer’s Disease and Dementia with Lewy Bodies via VMAT2 and Amyloid Imaging
Authors: Villemagne Victor L. , Okamura Nobuyuki , Pejoska Svetlana , Drago John , Mulligan Rachel S. , Chételat Gaël , O’Keefe Graeme , Jones Gareth , Kung Hank F. , Pontecorvo Michael , Masters Colin L. , Skovronsky Daniel M. , Rowe Christopher C.
Published: January 2012

Background: The noninvasive evaluation of nigrostriatal dopaminergic integrity by PET can provide useful information for the differential diagnosis between dementia with Lewy bodies (DLB) and Alzheimer’s disease (AD). Objectives: To evaluate the diagnostic potential of imaging striatal monoaminergic terminal integrity with the novel vesicular monoamine transporter type 2 (VMAT2) radioligand [18F]AV-133 and PET to distinguish DLB from AD. Methods: Fifty participants [9 DLB, 11 AD, 20 Parkinson’s disease (PD) and 10 healthy age-matched control subjects (HC)] underwent [18F]AV-133 PET studies. Additionally, 20 participants underwent amyloid imaging PET scans with either [11C]PiB or 18F-florbetaben. VMAT2 density was calculated through normalized tissue uptake value ratios (RT) at 120–140 min after injection using the primary visual or the cerebellar cortex as reference region. Comparison of the RT for [18F]AV-133 was done between the different clinical diagnostic groups. Results: Significantly lower striatal VMAT2 densities were observed in DLB and PD when compared to AD and HC, especially in the posterior putamen. In contrast to PD and DLB, no reductions were observed in AD patients when compared to HC. Conclusions: [18F]AV-133 allows assessment of nigrostriatal degeneration in Lewy body diseases. In contrast to amyloid imaging, VMAT2 imaging with [18F]AV-133 can robustly detect reductions of dopaminergic nigrostriatal afferents in DLB patients, assisting in the differential diagnosis from AD.
α-Lipoic Acid, Diabetic Neuropathy, and Nathan’s Prophecy
Authors: Papanas N. , Maltezos E.
Published: January 2012

Both oral and intravenous administration of alpha-lipoic acid (ALA) has been investigated as add-on treatment for diabetic peripheral neuropathy. The recent Neurological Assessment of Thioctic Acid in Diabetic Neuropathy (NATHAN) 1 trial has shown that 4-year oral ALA administration is of some value in achieving a clinically meaningful improvement and a slight delay in the progression of neuropathic deficits among patients with mild/moderate diabetic peripheral neuropathy. Despite these promising results, important questions remain to be answered, mainly appropriate patient selection and optimal treatment duration. Moreover, a cost-benefit analysis would be useful.
Assisted dying in liberalised jurisdictions and the role of psychiatry: A clinician’s view
Authors: Macleod Sandy
Published: January 2012

Objective:

Assisted dying is a contentious and topical issue. Mental disorder is a relevant influence on requests of hastened death. The psychiatry of dying is not a prominent component in the assessment of euthanasia and physician-assisted suicide (PAS) in jurisdictions with liberalised assisted dying laws. The literature on the assessment processes, with particular reference to mental status, involved in euthanasia requests is considered.

Methods:

An experienced palliative medicine specialist and psychiatrist selectively reviewed the recent literature published about the mental health issues involved in euthanasia and PAS.

Results:

Assessments of competency, sustained wish to die prematurely, depressive disorder, demoralisation and ‘unbearable suffering’ in the terminally ill are clinically uncertain and difficult tasks. There is a growing psychiatric and psychological literature on the mental status of the terminally ill. As yet psychiatry does not have the expertise to ‘select’ those whose wish for hastened death is rational, humane and ‘healthy’. Rarely in those societies with liberalised assisted dying laws are psychiatrists involved in the decision-making for individuals requesting early death. This role is fulfilled by non-specialists.

Conclusions:

There remain significant concerns about the accuracy of psychiatric assessment in the terminally ill. Mental processes are more relevant influences on a hastened wish to die than are the physical symptoms of terminal malignant disease. Psychiatric review of persons requesting euthanasia is relevant. It is not obligatory or emphasised in those legislations allowing assisted dying. Psychiatry needs to play a greater role in the assessment processes of euthanasia and PAS.
An Avant-Garde Architecture for an Avant-Garde Socialism: Yugoslavia at EXPO ’58
Authors: Kulić Vladimir
Published: January 2012

The Pavilion of Yugoslavia at EXPO ’58 in Brussels was an attempt to internationally showcase the specific brand of socialism developed in that country since its break from the Soviet bloc ten years prior. That goal was best achieved through the pavilion building, an inspired piece of modern architecture designed by the Croatian architect Vjenceslav Richter, which attracted much positive attention. In most other respects, the presentation was a relative disappointment, failing to engage the visitors in an attractive and well-rounded experience. This article provides an analysis of the conceptualization, development, and reception of the pavilion based on the abundant material from the Archive of Yugoslavia in Belgrade. It argues that Richter’s avant-garde design resonated with the self-proclaimed avant-garde status of Yugoslav socialism, but that its complex connotations, when seen through the lens of the Cold War, were reduced to a mere index of Yugoslavia’s break from the Soviet bloc.
Immunological method for the identification of animal hair fibres
Authors: Tonetti Cinzia , Vineis Claudia , Aluigi Annalisa , Tonin Claudio
Published: January 2012

A new approach to the objective identification of the different animal hair fibres based on the application of monoclonal antibodies has been discussed. Three different extraction methods including metabisulphite/urea, dithiothreitol/urea, thiourea/urea/dithiothreitol were compared to evaluate efficiency and repeatability in extracting keratin from wool and cashmere fibres.

 ‘Anti-cashmere’ monoclonal antibodies were produced by immunization of mice with Type II intermediate filament proteins extracted from cashmere, purified by 2D preparative electrophoresis.

Two monoclonal antibodies (named P21 and I6) were tested with both wool and cashmere blends for both qualitative and quantitative analysis. The interaction of P21 and I6 antibodies was studied by the immunoblot method.

 After a calibration carried out on both the antibodies, the method was applied to unknown wool/cashmere blends and compared with the results of the analysis carried out by the SEM (scanning electron microscopy) method IWTO 58-00 in order to preliminarily assess the method.