bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical evaluation of a medical high dynamic range display
Authors: Marchessoux Cedric , de Paepe Lode , Vanovermeire Olivier , Albani Luigi
Published: June 2016

Purpose:

Recent new medical displays do have higher contrast and higher luminance but do not have a High Dynamic Range (HDR). HDR implies a minimum luminance value close to zero. A medical HDR display prototype based on two Liquid Crystal layers has been developed. The goal of this study is to evaluate the potential clinical benefit of such display in comparison with a low dynamic range (LDR) display.

Methods:

The study evaluated the clinical performance of the displays in a search and detection task. Eight radiologists read chest x‐ray images some of which contained simulated lung nodules. The study used a JAFROC (Jacknife Free Receiver Operating Characteristic) approach for analyzing FROC data. The calculated figure of merit (FoM) is the probability that a lesion is rated higher than all rated nonlesions on all images. Time per case and accuracy for locating the center of the nodules were also compared. The nodules were simulated using Samei's model. 214 CR and DR images [half were “healthy images” (chest nodule‐free) and half “diseased images”] were used resulting in a total number of nodules equal to 199 with 25 images with 1 nodule, 51 images with 2 nodules, and 24 images with 3 nodules. A dedicated software interface was designed for visualizing the images for each session. For the JAFROC1 statistical analysis, the study is done per nodule category: all nodules, difficult nodules, and very difficult nodules.

Results:

For all nodules, the averaged FoMHDR is slightly higher than FoMLDR with 0.09% of difference. For the difficult nodules, the averaged FoMHDR is slightly higher than FoMLDR with 1.38% of difference. The averaged FoMHDR is slightly higher than FoMLDR with 0.71% of difference. For the true positive fraction (TPF), both displays (the HDR and the LDR ones) have similar TPF for all nodules, but looking at difficult and very difficult nodules, there are more TP for the HDR display. The true positive fraction has been also computed in function of the local average luminance around the nodules. For the lowest luminance range, there is more than 30% in favor of the HDR display. For the highest luminance range, there is less than 6% in favor of the LDR display.

Conclusions:

This study shows the potential benefit of using a HDR display in radiology.
Characterization of air temperature in modern ion chambers due to phantom geometry and ambient temperature changes
Authors: Saenz Daniel L. , Kirby Neil , Gutiérrez Alonso N.
Published: June 2016

Purpose:

Temperature and pressure corrections are necessary to account for the varying mass of air in the sensitive volume of a vented ionization chamber (IC) when performing absolute dose measurements. Locations commonly used to measure the presumed IC air temperature may not accurately represent the chamber cavity air temperature, and phantoms undergoing temperature changes further compound the problem. Prior studies have characterized thermal equilibrium in separate phantoms for Farmer chambers alone. However, the purpose of this study was to characterize the cavity air temperature dependence on changes in the ambient temperature and phantom geometry configuration for a wider and more modern variety of chambers to determine if previously published wait times apply to these chambers as well.

Methods:

Thermal conduction properties were experimentally investigated by modifying a PTW 0.3 cm3 Semiflex IC with a thermocouple replacing the central electrode. Air cavity temperature versus time was recorded in three phantom geometries characteristic of common absolute dose measurements. The phantoms were (15 ± 1) °C before measurement with an IC at the treatment vault temperature of (21 ± 1) °C. Simulations were conducted to provide a theoretical basis for the measurements and to simulate temperature response of a PTW PinPoint® and Farmer chamber. The simulation methods were first validated by comparison with measured Semiflex chamber thermal response curves before extension to the other chambers.

Results:

Two thermal equilibria curves were recorded on different time scales. IC temperature initially dropped to the colder phantom temperature but subsequently increased as the phantom itself equilibrated with the warmer room temperature. In a large phantom of dimensions (25.5 × 25.5 × 23.4) cm3, 3 min was required before the IC temperature reached within 0.5 °C of its equilibrium within the phantom. Similarly, wait times of 2 min were needed for 7.5 and 2 cm slab phantoms.

Conclusions:

Recording of temperature in the phantom was deemed far more accurate than measurement in ambient air due to the air cavity thermally equilibrating with phantom temperature instead of the vented ambient air. Wait times of 3 and 2 min are needed for a cube and 7.5 cm slab phantom, respectively, to achieve 0.2% dosimetric accuracy (temperature accuracy of 0.5 °C). Chamber volume alone did not determine wait times, as a 0.3 cm3 IC required a longer wait time than a Farmer chamber, suggesting wall thickness as an important variable as well.
Coalescence in PLA-PBAT blends under shear flow: Effects of blend preparation and PLA molecular weight
Authors: Nofar M. , Heuzey M. C. , Carreau P. J. , Kamal M. R. , Randall J.
Published: June 2016

Blends containing 75 wt. % of an amorphous polylactide (PLA) with two different molecular weights and 25 wt. % of a poly[(butylene adipate)-co-terephthalate] (PBAT) were prepared using either a Brabender batch mixer or a twin-screw extruder. These compounds were selected because blending PLA with PBAT can overcome various drawbacks of PLA such as its brittleness and processability limitations. In this study, we investigated the effects of varying the molecular weight of the PLA matrix and of two different mixing processes on the blend morphology and, further, on droplet coalescence during shearing. The rheological properties of these blends were investigated and the interfacial properties were analyzed using the Palierne emulsion model. Droplet coalescence was investigated by applying shear flows of 0.05 and 0.20 s−1 at a fixed strain of 60. Subsequently, small amplitude oscillatory shear tests were conducted to investigate changes in the viscoelastic properties. The morphology of the blends was also examined using scanning electron microscope (SEM) micrographs. It was observed that the PBAT droplets were much smaller when twin-screw extrusion was used for the blend preparation. Shearing at 0.05 s−1 induced significant droplet coalescence in all blends, but coalescence and changes in the viscoelastic properties were much more pronounced for the PLA-PBAT blend based on a lower molecular weight PLA. The viscoelastic responses were also somehow affected by the thermal degradation of the PLA matrix during the experiments.
From Assessment to Purchase: A Three-Stage Model of the Marketing Funnel in Sponsorship Activities
Authors: Visentin Marco , Scarpi Daniele , Pizzi Gabriele
Published: June 2016

In this research we develop a comprehensive model of sponsorship effects accounting for behavioral outcomes such as actual purchase, purchase intentions, and word-of-mouth referral intention. We recombine constructs that have been traditionally considered separately into three stages—assessment, elaboration, and behavior. We collect data on actual customers of Nike and Adidas flagship stores during the FIFA World Cup sponsorship. Basing on our results, we provide a consumer-oriented perspective on the role of attitude toward the brand, fit, and involvement with the event in determining customer reaction to sponsorship activities.
The Contributions of Special Events to Sport-for-Development Programs
Authors: Schulenkorf Nico
Published: June 2016

For several years, sport-for-development (SFD) programs have been implemented around the world to make a positive difference for disadvantaged or underprivileged communities. Within this context, special events have been used to complement regular development activities to celebrate social, cultural, and sporting achievements. To date, little managerial work has been conducted on the specific contributions that special events can play in the context of ongoing SFD endeavors. In addressing this issue, this paper presents findings from an empirical investigation of a participatory SFD event in the Pacific Islands. Findings suggest that special events can create new interest and excitement for SFD activities, reengage stakeholders to the wider SFD program, leverage partnerships, and provide opportunities to build and shape local management capacity. In discussing these findings, the paper highlights potential positive and negative impacts of special SFD events and provides practical and theoretical implications for SFD program design, management, and leverage.
Whole-Genome Sequences of Seven Strains of Bacillus cereus Isolated from Foodstuff or Poisoning Incidents
Authors: Crovadore Julien , Calmin Gautier , Tonacini Jenna , Chablais Romain , Schnyder Bruno , Messelhäußer Ute , Lefort François
Published: June 2016

We present here the whole shotgun genome sequences of seven strains of
Bacillus cereus
isolated from foodstuff samples or food poisoning incidents.
Draft Genome Sequence of Lactobacillus collinoides CUPV237, an Exopolysaccharide and Riboflavin Producer Isolated from Cider
Authors: Puertas Ana Isabel , Capozzi Vittorio , Llamas María Goretti , López Paloma , Lamontanara Antonella , Orrù Luigi , Russo Pasquale , Spano Giuseppe , Dueñas María Teresa
Published: June 2016

Lactobacillus collinoides
CUPV237 is a strain isolated from a Basque cider.
Lactobacillus collinoides
is one of the most frequent species found in cider from Spain, France, or England. A notable feature of the
L. collinoides
CUPV237 strain is its ability to produce exopolysaccharides.
Complete Genome Sequence of Mesorhizobium ciceri bv. biserrulae Strain WSM1284, an Efficient Nitrogen-Fixing Microsymbiont of the Pasture Legume
Biserrula pelecinus
Authors: Haskett Timothy , Wang Penghao , Ramsay Joshua , O'Hara Graham , Reeve Wayne , Howieson John , Terpolilli Jason
Published: June 2016

We report the complete genome sequence of
Mesorhizobium ciceri
bv. biserrulae strain WSM1284, a nitrogen-fixing microsymbiont of the pasture legume
Biserrula pelecinus
. The genome consists of 6.88 Mb distributed between a single chromosome (6.33 Mb) and a single plasmid (0.55 Mb).
Genome Sequences of Multiresistant Staphylococcus capitis Pulsotype NRCS-A and Methicillin-Susceptible
S. capitis
Pulsotype NRCS-C
Authors: Lemriss H. , Dumont Y. , Lemriss S. , Martins-Simoes P. , Butin M. , Lahlou L. , Rasigade J. P. , El Kabbaj S. , Laurent F. , Ibrahimi A.
Published: June 2016

Here, we report the draft genome sequences of methicillin-susceptible
Staphylococcus captis
pulsotype NCRS-C (CR02 strain) and multiresistant
Staphylococcus captis
pulsotype NCRS-A (CR07 strain).
Draft Genome Sequence of Dietzia maris DSM 43672, a Gram-Positive Bacterium of the Mycolata Group
Authors: Ganguly Sonalli , Jimenez-Galisteo Guadalupe , Pletzer Daniel , Winterhalter Mathias , Benz Roland , Viñas Miguel
Published: June 2016

Here, we report the draft genome sequence of
Dietzia maris
, known previously as
Rhodococcus maris
. It is 3,505,372 bp in size with a G+C content of 73%. The draft genome sequence will improve our understanding of
Dietzia maris
related to other mycolata species and constitutes a basic tool for exploring the cell wall proteins.
Successful treatment of hepatitis C, genotype 3, with sofosbuvir/ledipasvir in decompensated cirrhosis complicated by mixed cryoglobulinaemia
Authors: Flemming Jennifer A , Lowe Catherine E
Published: June 2016

Advances in the treatment of chronic hepatitis C (HCV) have given HCV providers access to treatment regimens able to achieve sustained virological response (SVR or ‘cure’) in the majority of patients. There are, however, groups of patients in whom HCV treatment outcomes with direct acting antivirals (DAAs) are suboptimal (genotype (GT) 3 patients, decompensated cirrhosis, renal failure) or have not been studied in large cohorts (patients with cryoglobulinaemia (CG)). This case outlines the successful eradication of GT-3 hepatitis C (HCV) in a patient with decompensated cirrhosis and renal failure secondary to mixed CG with DAA failure, using a 12-week course of sofosbuvir, ledipasvir and ribavirin. The achievement of SVR in this patient resulted in significant improvement in hepatic and renal function. Patients with decompensated cirrhosis and GT-3 disease remain a difficult to treat population, and the safety and efficacy of sofosbuvir, ledipasvir and ribavirin in this cohort require further study.
Differential physiological response to sea lamprey parasitism between lake trout (Salvelinus namaycush) morphotypes from Lake Superior
Authors: Smith Sara E. , Sitar Shawn P. , Goetz Frederick W. , Huertas Mar , Armstrong Brandon M. , Murphy Cheryl A.
Published: June 2016

Assessment of stress from varied sources is usually evaluated using individuals derived from a single population and is assumed to represent all populations of that species. However, recent research has identified intraspecies variations in the stress response, which may be mediated by life history. We examined how life history can influence the physiological responses to an acute stress event by evaluating sea lamprey (Petromyzon marinus) parasitism response in two lake trout (Salvelinus namaycush) morphotypes: the lean and the siscowet. The morphotypes differ in that the lean grows faster, is more fecund, and has a shorter life span. In contrast, the siscowet grows slower, is older at maturity, and lives longer. Our study compared long-term parasitism responses between wild leans and siscowets in Lake Superior and immediate responses in laboratory parasitism trials using lake trout reared under common environmental conditions. Leans, but not siscowets, showed changes in steroid-binding protein function and weak evidence of gigantism in response to parasitism. Both morphotypes showed indications of reproductive endocrine alterations in response to parasitism. Our results demonstrate intraspecies variation in physiological stressor response, which is mediated by life history differences that could potentially have differential population implications.
Characterization of two LuxI/R homologs in Pantoea ananatis LMG 2665T
Authors: Sibanda Siphathele , Theron Jacques , Shyntum Divine Y. , Moleleki Lucy N. , Coutinho Teresa A.
Published: June 2016

Quorum sensing (QS) plays an important role in the regulation of bacteria–host interactions and ecological fitness in many bacteria. In this study, 2 luxI/R homologs, namely eanI/eanR and rhlI/rhlR, were identified in the genome sequence of Pantoea ananatis LMG 2665T. To determine a role for these luxI/R homologs in pathogenicity and biofilm formation, mutant bacterial strains lacking either eanI/R or rhlI/R and both of these homologs were generated. The results indicated that both the RhlI/R and EanI/R systems are required for pathogenicity and biofilm formation in strain LMG 2665T. This is the first study to characterize the biological significance of the RhlI/R QS system in P. ananatis.
Local characterizations of complex curves in C2 and sphere Schwarz maps
Authors: Ando Naoya
Published: June 2016

In this paper, we obtain a local characterization of a complex curve in [Formula: see text] in terms of the induced metric and a holomorphic cubic differential [Formula: see text], and we see that any complex curve in [Formula: see text] is locally represented as the image by the composition of an affine Schwarz map and a parallel translation in [Formula: see text]. We obtain a local characterization of a sphere Schwarz immersion in terms of a positive-valued function [Formula: see text].
(DE)STABILIZING EXCHANGE RATE STRATEGIES IN EAST ASIAN MONETARY AND ECONOMIC INTEGRATION
Authors: SCHNABL GUNTHER , SPANTIG KRISTINA
Published: June 2016

The East Asian monetary integration process is at the crossroads. Given very benign liquidity conditions in the US, the prevailing common US dollar peg has contributed to growing macroeconomic and financial instability in the region. This has sparked demands to embark on an independent monetary integration process in East Asia. The paper shows that, however, neither the Japanese yen nor the Chinese yuan can challenge the US dollar as anchor currency in the region. Large fluctuations of the Japanese yen against the US dollar have undermined the potential of the Japanese yen to become a regional anchor currency. Exchange rate stability of the Chinese yuan against the US dollar has enhanced intra-regional exchange rate stability and growth, stressing the potential of the Chinese yuan to emerge as a regional anchor currency. Yet, it is shown that underdeveloped Chinese capital markets and financial repression originating in US low interest rate policies constitute an insurmountable impediment for the Chinese yuan to gain anchor currency status in East Asia. Empirical estimations provide evidence in favor of positive growth effects of the exchange rate stability against the US dollar in East Asia.
Effect of CuO2 planes on the structural and superconducting transport properties of [CuTl − 12(n − 1)n;n = 2,3,4] superconductor family
Authors: Muzaffar M. Usman , Khan Nawazish A.
Published: June 2016

[Formula: see text] [Formula: see text] superconducting bulk samples have been synthesized by using two-step solid state reaction method. We investigated the effects of [Formula: see text] planes on the structural and superconducting transport properties of [Formula: see text] superconducting family. These samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) absorption spectroscopy and DC-resistivity [Formula: see text] measurements. These samples are [Formula: see text]-axis length oriented and have shown orthorhombic crystal structure. All the samples have shown metallic variations of resistivity from room temperature down to onset of superconductivity. The zero resistivity critical temperature [Formula: see text] increases with the increase in superconducting planes and normal state resistivity systematically decreases, which show the density of inadvertent defects decreases in the final compound. The apical oxygen phonon modes are hardened as observed in the FTIR absorption measurements. The intrinsic microscopic superconducting parameters, such as the cross-over temperatures, coherence length along [Formula: see text]-axis [Formula: see text] at 0 K, inter-layer coupling [Formula: see text], inter-grain coupling [Formula: see text] and fermi velocity [Formula: see text], were extracted from the fluctuation-induced conductivity (FIC) analysis. FIC analysis also showed the improvement in superconductivity with the increase in [Formula: see text] planes.
On construction of surface-knots
Authors: Mohamad A. , Yashiro T.
Published: June 2016

In this paper, we present a construction of a family of surface-knot diagrams with cross-exchangeable curves, along which we can change the crossing information to obtain trivial diagrams. These diagrams also satisfy a kind of minimality, called [Formula: see text]-minimal surface-knot diagrams.
Schrödinger-like quantum dynamics in loop quantized black holes
Authors: Gambini Rodolfo , Olmedo Javier , Pullin Jorge
Published: June 2016

We show, following a previous quantization of a vacuum spherically symmetric spacetime carried out in [R. Gambini, J. Olmedo and J. Pullin, Class. Quantum Grav. 31 (2014) 095009.] that this setting admits a Schrödinger-like picture. More precisely, the technique adopted there for the definition of parametrized Dirac observables (that codify local information of the quantum theory) can be extended in order to accommodate different pictures. In this new picture, the quantum states are parametrized in terms of suitable gauge parameters and the observables constructed out of the kinematical ones on this space of parametrized states.
Gauge invariant nonlocal quantum dynamics of the Aharonov–Bohm effect and how it may be tested
Authors: Kaufherr T.
Published: June 2016

The gauge invariant nonlocal quantum dynamics that is responsible for the Aharonov–Bohm (AB) effect is described. It is shown that it may be verified experimentally.
On Darboux rotation axis of lightlike curves
Authors: Şekerci Gülşah Aydın , Çöken Abdilkadir Ceylan , Ekici Cumali
Published: June 2016

In this paper, by used Frenet trihedron for a lightlike curve, the motion of Darboux rotation axis is seperated to two simultaneous rotation motions. These rotation motions are that tangent and normal vectors of lightlike curve rotate around each other. But, the angular speeds of them are different. Then, by doing the similar operations, we obtain that Darboux axis rotates around spacelike vector of Frenet trihedron of the lightlike curve and this spacelike vector rotates around Darboux axis. Consequently, we obtain the series of Darboux vectors by this way. So, simple mechanisms can be formed.
Hydrothermal Synthesis of Few-Layer and Edge-Rich Cobalt-Doped Molybdenum Selenide/Nitrogenated Graphene Composite and Investigation of Its Electrocatalytic Activity for Hydrogen Evolution Reaction
Authors: Ou Ming , Ma Lin , Xu Limei , Yang Zhuomei , Li Haizhen
Published: June 2016

Cobalt-doped MoSe2/nitrogenated graphene composite has been successfully synthesized via a facile hydrothermal route and is investigated as an electrocatalyst for hydrogen evolution reaction (HER). The as-prepared samples are well characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and Raman spectrum. The results reveal that Co-doped MoSe2 nanosheets which are characteristic of few layers (2–4 layers) and abundant exposed active edge sites are well anchored on the nitrogen-doped graphene sheets to constitute robust composites. When evaluated as catalysts for HER, the obtained composites demonstrate superior electrocatalytic activities toward HER.
Isoclinism of crossed modules
Authors: Salemkar Ali Reza , Mohammadzadeh Hamid , Shahrokhi Saeed
Published: June 2016

In this paper, we introduce the notion of the equivalence relation, isoclinism, on crossed modules of groups, and give some equivalent conditions for crossed modules to be isoclinic. In particular, it is shown that if two crossed modules [Formula: see text] and [Formula: see text] are isoclinic then [Formula: see text] can be constructed from [Formula: see text] and vice versa using the operations of forming direct products, taking crossed submodules, and factoring crossed modules, which generalizes the work of Weichsel. Also, similar to a result of Hall in the group case, we show that any equivalence class of crossed modules contains at least one stem crossed module.
Performance Evaluation of Dynamic Page Allocation Strategies in SSDs
Authors: Tavakkol Arash , Mehrvarzy Pooyan , Arjomand Mohammad , Sarbazi-Azad Hamid
Published: June 2016

Solid-state drives (SSDs) with tens of NAND flash chips and highly parallel architectures are widely used in enterprise and client storage systems. As any write operation in NAND flash is preceded by a slow erase operation, an out-of-place update mechanism is used to distribute writes through SSD storage space to postpone erase operations as far as possible. SSD controllers use a mapping table along with a specific allocation strategy to map logical host addresses to physical page addresses within storage space. The allocation strategy is further responsible for accelerating I/O operations through better striping of physical addresses over SSD parallel resources. Proposals already exist for using static logical-to-physical address mapping that does not balance the I/O traffic load within the SSD, and its efficiency highly depends on access patterns. A more balanced distribution of I/O operations is to alternate resource allocation in a round-robin manner irrespective of logical addresses. The number of resources that can be dynamically allocated in this fashion is defined as the degree of freedom, and to the best of our knowledge, there has been no research thus far to show what happens if different degrees of freedom are used in allocation strategy. This article explores the possibility of using dynamic resource allocation and identifies key design opportunities that it presents to improve SSD performance. Specifically, using steady-state analysis of SSDs, we show that dynamism helps to mitigate performance and endurance overheads of garbage collection. Our steady-state experiments indicate that midrange/high-end SSDs with dynamic allocation can provide I/O operations per second (IOPS) improvement of up to 3.3x/9.6x, response time improvement of up to 56%/32%, and about 88%/96% average reduction in the standard deviation of erase counts of NAND flash blocks.
An Efficient Multidimensional Big Data Fusion Approach in Machine-to-Machine Communication
Authors: Ahmad Awais , Paul Anand , Rathore Mazhar , Chang Hangbae
Published: June 2016

Machine-to-Machine communication (M2M) is nowadays increasingly becoming a world-wide network of interconnected devices uniquely addressable, via standard communication protocols. The prevalence of M2M is bound to generate a massive volume of heterogeneous, multisource, dynamic, and sparse data, which leads a system towards major computational challenges, such as, analysis, aggregation, and storage. Moreover, a critical problem arises to extract the useful information in an efficient manner from the massive volume of data. Hence, to govern an adequate quality of the analysis, diverse and capacious data needs to be aggregated and fused. Therefore, it is imperative to enhance the computational efficiency for fusing and analyzing the massive volume of data. Therefore, to address these issues, this article proposes an efficient, multidimensional, big data analytical architecture based on the fusion model. The basic concept implicates the division of magnitudes (attributes), i.e., big datasets with complex magnitudes can be altered into smaller data subsets using five levels of the fusion model that can be easily processed by the Hadoop Processing Server, resulting in formalizing the problem of feature extraction applications using earth observatory system, social networking, or networking applications. Moreover, a four-layered network architecture is also proposed that fulfills the basic requirements of the analytical architecture. The feasibility and efficiency of the proposed algorithms used in the fusion model are implemented on Hadoop single-node setup on UBUNTU 14.04 LTS core i5 machine with 3.2GHz processor and 4GB memory. The results show that the proposed system architecture efficiently extracts various features (such as land and sea) from the massive volume of satellite data.
A New Compilation Flow for Software-Defined Radio Applications on Heterogeneous MPSoCs
Authors: Dardaillon Mickaël , Marquet Kevin , Risset Tanguy , Martin Jérôme , Charles Henri-Pierre
Published: June 2016

The advent of portable software-defined radio (
sdr
) technology is tightly linked to the resolution of a difficult problem: efficient compilation of signal processing applications on embedded computing devices. Modern wireless communication protocols use packet processing rather than infinite stream processing and also introduce dependencies between data value and computation behavior leading to dynamic dataflow behavior. Recently, parametric dataflow has been proposed to support dynamicity while maintaining the high level of analyzability needed for efficient real-life implementations of signal processing computations.

This article presents a new compilation flow that is able to compile parametric dataflow graphs. Built on the
llvm
compiler infrastructure, the compiler offers an actor-based C++ programming model to describe parametric graphs, a compilation front end for graph analysis, and a back end that currently matches the Magali platform: a prototype heterogeneous MPSoC dedicated to LTE-Advanced. We also introduce an innovative scheduling technique, called
microscheduling
, allowing one to adapt the mapping of parametric dataflow programs to the specificities of the different possible MPSoCs targeted. A specific focus on
fifo
sizing on the target architecture is presented. The experimental results show compilation of 3
gpp
lte
-
a
dvanced demodulation on Magali with tight memory size constraints. The compiled programs achieve performance similar to handwritten code.
Undergraduate Students’ Perceptions of the Impact of Pre-College Computing Activities on Choices of Major
Authors: McGill Monica M. , Decker Adrienne , Settle Amber
Published: June 2016

A lack of diversity in the computing field has existed for several decades, and although female participation in computing remains low, outreach programs attempting to address the situation are now quite numerous. To begin to understand whether or not these past activities have had long-term impact, we conducted a systematic literature review. Upon discovering that longitudinal studies were lacking, we investigated whether undergraduate students believed that their participation in computing activities prior to college contributed to their decision to major in a computing field. From the 770 participants in the study, we discovered that approximately 20% of males and 24% of females who were required to participate in computing activities chose a computing or related major, but that males perceived that the activity had a greater affect on their decision (20%) than females (6.9%). Females who participated in an outreach activity were more likely to major in computing. Compared with females who chose to major in computing, females who did not were less likely to indicate that the majority of students participating in activities were boys and that they were a welcome part of the groups. Results also showed that female participants who do not ultimately major in computing have a much stronger negative perception of the outreach activities than male participants who also chose a non-computing major. Although many computing outreach activities are designed to diversify computing, it may be the case that, overall, boys receive these activities more favorably than girls, although requiring participation yields approximately the same net positive impact.
Query Performance Prediction Using Reference Lists
Authors: Shtok Anna , Kurland Oren , Carmel David
Published: June 2016

The task of query performance prediction is to estimate the effectiveness of search performed in response to a query when no relevance judgments are available. We present a novel probabilistic analysis of the performance prediction task. The analysis gives rise to a general prediction framework that uses pseudo-effective or ineffective document lists that are retrieved in response to the query. These lists serve as reference to the result list at hand, the effectiveness of which we want to predict. We show that many previously proposed prediction methods can be explained using our framework. More generally, we shed new light on existing prediction methods and establish formal common grounds to seemingly different prediction approaches. In addition, we formally demonstrate the connection between prediction using reference lists and fusion of retrieved lists, and provide empirical support to this connection. Through an extensive empirical exploration, we study various factors that affect the quality of prediction using reference lists.
Computational Geometry Column 63
Authors: Klein Rolf , Langetepe Elmar
Published: June 2016

Assume that a fire spreads inside a geometric environment. The fire-fighter's task is to extinguish the fire, or to build a barrier that encloses and stops the fire. This problem has been considered in many different models and variants. For example, the spreading can occur in a discrete world or in the continuous plane. Many computational questions arise. How fast must the fighters be in comparison to the fire's speed, in order to fulfill their task? How many fire-fighters are necessary and sufficient? How can they enclose the fire as efficiently as possible? Of the wealth of existing results we present some appetizers indicating the wide range of this topic, and mention a number of open questions.
Guest Column
Authors: Razborov Alexander
Published: June 2016

This essay is a highly personal and biased account of some main concepts and several research directions in modern propositional proof complexity. Special attention will be paid to connections with other disciplines.
How to Build Static Checking Systems Using Orders of Magnitude Less Code
Authors: Brown Fraser , Nötzli Andres , Engler Dawson
Published: June 2016

Modern static bug finding tools are complex. They typically consist of hundreds of thousands of lines of code, and most of them are wedded to one language (or even one compiler). This complexity makes the systems hard to understand, hard to debug, and hard to retarget to new languages, thereby dramatically limiting their scope. This paper reduces checking system complexity by addressing a fundamental assumption, the assumption that checkers must depend on a full-blown language specification and compiler front end. Instead, our program checkers are based on drastically incomplete language grammars ("micro-grammars") that describe only portions of a language relevant to a checker. As a result, our implementation is tiny-roughly 2500 lines of code, about two orders of magnitude smaller than a typical system. We hope that this dramatic increase in simplicity will allow people to use more checkers on more systems in more languages.

We implement our approach in μchex, a language-agnostic framework for writing static bug checkers. We use it to build micro-grammar based checkers for six languages (C, the C preprocessor, C++, Java, JavaScript, and Dart) and find over 700 errors in real-world projects.
ReBudget
Authors: Wang Xiaodong , Martínez José F.
Published: June 2016

Efficiently allocating shared resources in computer systems is critical to optimizing execution. Recently, a number of market-based solutions have been proposed to attack this problem. Some of them provide provable theoretical bounds to efficiency and/or fairness losses under market equilibrium. However, they are limited to markets with potentially important constraints, such as enforcing equal budget for all players, or curve-fitting players' utility into a specific function type. Moreover, they do not generally provide an intuitive "knob" to control efficiency vs. fairness. In this paper, we introduce two new metrics, Market Utility Range (MUR) and Market Budget Range (MBR), through which we provide for the first time theoretical bounds on efficiency and fairness of market equilibria under
arbitrary
budget assignments. We leverage this result and propose
ReBudget
, an iterative budget re-assignment algorithm that can be used to control efficiency vs. fairness at run-time. We apply our algorithm to a multi-resource allocation problem in multicore chips. Our evaluation using detailed execution-driven simulations shows that our budget re-assignment technique is intuitive, effective, and efficient.
NVWAL
Authors: Kim Wook-Hee , Kim Jinwoong , Baek Woongki , Nam Beomseok , Won Youjip
Published: June 2016

Emerging byte-addressable non-volatile memory is considered an alternative storage device for database logs that require persistency and high performance. In this work, we develop NVWAL (NVRAM Write-Ahead Logging) for SQLite. The contribution of NVWAL consists of three elements: (i) byte-granularity differential logging that effectively eliminates the excessive I/O overhead of filesystem-based logging or journaling, (ii) transaction-aware lazy synchronization that reduces cache synchronization overhead by two-thirds, and (iii) user-level heap management of the NVRAM persistent WAL structure, which reduces the overhead of managing persistent objects.

We implemented NVWAL in SQLite and measured the performance on a Nexus 5 smartphone and an NVRAM emulation board - Tuna. Our performance study shows the following: (i) the overhead of enforcing strict ordering of NVRAM writes can be reduced via NVRAM-aware transaction management. (ii) From the application performance point of view, the overhead of guaranteeing failure atomicity is negligible; the cache line flush overhead accounts for only 0.8~4.6% of transaction execution time. Therefore, application performance is much less sensitive to the NVRAM performance than we expected. Decreasing the NVRAM latency by one-fifth (from 1942 nsec to 437 nsec), SQLite achieves a mere 4% performance gain (from 2517 ins/sec to 2621 ins/sec). (iii) Overall, when the write latency of NVRAM is 2 usec, NVWAL increases SQLite performance by at least 10x compared to that of WAL on flash memory (from 541 ins/sec to 5812 ins/sec).
Cogent
Authors: Amani Sidney , Hixon Alex , Chen Zilin , Rizkallah Christine , Chubb Peter , O'Connor Liam , Beeren Joel , Nagashima Yutaka , Lim Japheth , Sewell Thomas , Tuong Joseph , Keller Gabriele , Murray Toby , Klein Gerwin , Heiser Gernot
Published: June 2016

We present an approach to writing and formally verifying high-assurance file-system code in a restricted language called Cogent, supported by a certifying compiler that produces C code, high-level specification of Cogent, and translation correctness proofs. The language is strongly typed and guarantees absence of a number of common file system implementation errors. We show how verification effort is drastically reduced for proving higher-level properties of the file system implementation by reasoning about the generated formal specification rather than its low-level C code. We use the framework to write two Linux file systems, and compare their performance with their native C implementations.
High-Density Image Storage Using Approximate Memory Cells
Authors: Guo Qing , Strauss Karin , Ceze Luis , Malvar Henrique S.
Published: June 2016

This paper proposes tailoring image encoding for an approximate storage substrate. We demonstrate that indiscriminately storing encoded images in approximate memory generates unacceptable and uncontrollable quality degradation. The key finding is that errors in the encoded bit streams have non-uniform impact on the decoded image quality. We develop a methodology to determine the relative importance of encoded bits and store them in an approximate storage substrate. The storage cells are optimized to reduce error rate via biasing and are tuned to meet the desired reliability requirement via selective error correction. In a case study with the progressive transform codec (PTC), a precursor to JPEG XR, the proposed approximate image storage system exhibits a 2.7x increase in density of pixels per silicon volume under bounded error rates, and this achievement is additive to the storage savings of PTC compression.
Generating Configurable Hardware from Parallel Patterns
Authors: Prabhakar Raghu , Koeplinger David , Brown Kevin J. , Lee HyoukJoong , De Sa Christopher , Kozyrakis Christos , Olukotun Kunle
Published: June 2016

In recent years the computing landscape has seen an increasing shift towards specialized accelerators. Field programmable gate arrays (FPGAs) are particularly promising for the implementation of these accelerators, as they offer significant performance and energy improvements over CPUs for a wide class of applications and are far more flexible than fixed-function ASICs. However, FPGAs are difficult to program. Traditional programming models for reconfigurable logic use low-level hardware description languages like Verilog and VHDL, which have none of the productivity features of modern software languages but produce very efficient designs, and low-level software languages like C and OpenCL coupled with high-level synthesis (HLS) tools that typically produce designs that are far less efficient. Functional languages with parallel patterns are a better fit for hardware generation because they provide high-level abstractions to programmers with little experience in hardware design and avoid many of the problems faced when generating hardware from imperative languages. In this paper, we identify two important optimizations for using parallel patterns to generate efficient hardware: tiling and metapipelining. We present a general representation of tiled parallel patterns, and provide rules for automatically tiling patterns and generating metapipelines. We demonstrate experimentally that these optimizations result in speedups up to 39.4× on a set of benchmarks from the data analytics domain.
Programming Uncertain hings
Authors: McKinley Kathryn S.
Published: June 2016

Innovation flourishes with good abstractions. For instance, codification of the IEEE Floating Point standard in 1985 was critical to the subsequent success of scientific computing. Programming languages currently lack appropriate abstractions for uncertain data. Applications already use estimates from sensors, machine learning, big data, humans, and approximate algorithms, but most programming languages do not help developers address correctness, programmability, and optimization problems due to estimates.

To address these problems, we propose a new programming abstraction called Uncertain embedded into languages, such as C#, C++, Java, Python, and JavaScript. Applications use familiar discrete operations for estimates with Uncertain. Overloaded conditional operators specify hypothesis tests and applications use them to control false positives and negatives. A simple compositional operator expresses domain knowledge. We carefully restrict expressiveness such that we can build a runtime that implements correct statistical reasoning at conditionals. Our system relieves developers of the need to implement or deeply understand statistics. We demonstrate substantial programmability, correctness, and efficiency benefits of this programming model for GPS sensor navigation, approximate computing, machine learning, and xBox.

We encourage the community to develop and use abstractions for estimates.
Genomic EWSR1 Fusion Sequence as Highly Sensitive and Dynamic Plasma Tumor Marker in Ewing Sarcoma
Authors: Krumbholz Manuela , Hellberg Julia , Steif Benedikt , Bäuerle Tobias , Gillmann Clarissa , Fritscher Torsten , Agaimy Abbas , Frey Benjamin , Juengert Joerg , Wardelmann Eva , Hartmann Wolfgang , Juergens Heribert , Dirksen Uta , Metzler Markus
Published: June 2016

Purpose: The application of the tumor-specific genomic fusion sequence as noninvasive biomarker for therapy monitoring in Ewing sarcoma (EwS) has been evaluated.

Experimental Design: EwS xenograft mouse models were used to explore detectability in small plasma volumes and correlation of genomic EWSR1-FLI1 copy numbers with tumor burden. Furthermore, 234 blood samples from 20 EwS patients were analyzed before and during multimodal treatment. EWSR1 fusion sequence levels in patients' plasma were quantified using droplet digital PCR and compared with tumor volumes calculated from MRI or CT imaging studies.

Results: Kinetics of EWSR1 fusion sequence copy numbers in the plasma are correlated with changes of the tumor volume in patients with localized and metastatic disease. The majority of patients showed a fast reduction of cell-free tumor DNA (ctDNA) during initial chemotherapy. Recurrence of increasing ctDNA levels signalized relapse development.

Conclusions: Genomic fusion sequences represent promising noninvasive biomarkers for improved therapy monitoring in EwS. Until now, response assessment is largely based on MRI and CT imaging, implying restrictions on closely repeated performance and limitations on the differentiation between vital tumor and reactive stromal tissue. Particularly in patients with prognostic unfavorable disseminated disease, ctDNA is a valuable addition for the assessment of therapy response. Clin Cancer Res; 22(17); 4356–65. ©2016 AACR.
Audiological Monitoring in Children Treated with Platinum Chemotherapy
Authors: Fetoni A.R. , Ruggiero A. , Lucidi D. , De Corso E. , Sergi B. , Conti G. , Paludetti G.
Published: June 2016

Platinum compounds constitute the standard treatment for solid tumors in pediatric oncology. The purpose of this study is to assess the impact of platinum compounds in the development of ototoxicity in children following chemotherapy. This study included 160 patients treated with cisplatin and carboplatin for malignant solid diseases from 2007 to 2014. Their audiograms were classified according to the Boston SIOP ototoxicity scale. Twenty-five percent of the children treated with platinum compounds developed ototoxicity. The incidence of ototoxicity was correlated with the type of platinum derivative (i.e. cisplatin vs. carboplatin), coadministration of both drugs and concomitant cranial radiotherapy, but not with sex and age. Cumulative dose was correlated only with the cisplatin administration. Nine patients (8.6%) showed further progression of hearing impairment after the end of chemotherapy. The low rate of ototoxicity suggests the pivotal role of auditory monitoring in children treated with platinum compounds in order to be able to identify hearing loss at an early stage and to provide, jointly with pediatric oncologists, strategies to reduce further progression of cochlear toxicity.
Human Epidermal Growth Factor Receptor 2 (HER-2/neu)-Directed Therapy for Rare Metastatic Epithelial Tumors with HER-2 Amplification
Authors: Shin Daniel Sanghoon , Sherry Timothy , Kallen Michael E. , Wong Steven , Drakaki Alexandra
Published: June 2016

Case 1: A 67-year-old Asian female was diagnosed with locally advanced high-grade salivary duct carcinoma in June 2011. Molecular analysis revealed human epidermal growth factor receptor 2 (HER-2) amplification. She received adjuvant therapy with carboplatin/paclitaxel/ trastuzumab and maintenance of trastuzumab. Upon disease progression, trastuzumab could not be continued due to lack of financial coverage. Instead, she was treated with compassionate use of lapatinib from April 2013 and standard 5-fluorouracil. Her disease ultimately progressed and she expired later in 2013. Case 2: A 68-year-old Asian male was diagnosed with extramammary Paget's disease of the scrotum with HER-2 amplification in May 2011. He received 6 cycles of adjuvant trastuzumab/docetaxel/carboplatin followed by maintenance trastuzumab, which was changed to compassionate use of lapatinib as his insurance did not cover further administration of trastuzumab. He showed clinical benefits from single-agent lapatinib and a combination of lapatinib/capecitabine upon progression to the single-agent lapatinib. Ultimately, he was started on ado-trastuzumab emtansine, which was approved at that time by the FDA for HER-2-positive breast cancer progressed on trastuzumab. He is having clinical and radiographic complete response based on current imaging and normalization of his tumor markers. Conclusion: HER-2-targeted therapy should be considered for tumors with HER-2 amplification. In our case series, we would like to emphasize this approach in other rare histologies. Specifically, our patient with extramammary Paget's disease of the scrotum represents the first reported case of a non-breast, non-gastric tumor with HER-2 overexpression with complete clinical and radiographic response to HER-2-targeted therapy.