bluuebunny/crossref_metadata_2025 huggingface dataset:
What Happens After Menopause? (WHAM): protocol for a prospective, multicentre, age-matched cohort trial of risk-reducing bilateral salpingo-oophorectomy in high-risk premenopausal women
Authors: Hickey Martha , Trainer Alison , Braat Sabine , Davey Mary-Ann , Krejany Efrosinia , Wark John
Published: November 2017

Introduction

Women at high inherited risk of ovarian cancer are advised to undergo risk-reducing bilateral salpingo-oophorectomy (RRBSO) at age 40–45 years or when their families are complete. Most women are premenopausal at this age, so RRBSO will induce surgical menopause. Despite the clear benefits of RRBSO for cancer risk reduction, much less is known about the impact on non-cancer outcomes that contribute to health and well-being and inform surveillance and management strategies.

Methods and analysis

This will be a multicentre, prospective cohort study of 105 premenopausal high-risk women undergoing RRBSO and an age-matched comparison group of 105 premenopausal women not planning oophorectomy or pregnancy in the next 2 years. The aim of this study is to measure the impact of RRBSO on sexual function (primary outcome) at 24 months in high-risk premenopausal women compared with the comparison group. Secondary outcomes include menopausal symptoms and menopause-related quality of life, mood, sleep quality, markers of cardiovascular disease and pre-diabetes, bone density and markers of bone turnover, and the impact of hormone replacement therapy use on these outcomes. Data analysis methods will include logistic and linear regression using general estimating equations accounting for the repeated outcome measurements within each participant.

Ethics and dissemination

The study has been approved by institutional ethics committees at each participating centre. Findings will be disseminated through peer-reviewed publications and conference presentations, and national and international networks of centres managing high-risk women, and will inform national and international clinical guidelines.

Trial registration number

The pre-results protocol for this trial is registered with the Australian New Zealand Clinical Trials Registry (anzctr.org.au; registration no: ACTRN12615000082505).
Challenges in delivering computed tomography coronary angiography as the first-line test for stable chest pain
Authors: Dreisbach John G , Nicol Edward D , Roobottom Carl A , Padley Simon , Roditi Giles
Published: November 2017

Objective

The National Institute for Health and Care Excellence (NICE) clinical guidelines ‘chest pain of recent onset: assessment and diagnosis’ (update 2016) state CT coronary angiography (CTCA) should be offered as the first-line investigation for patients with stable chest pain. However, the current provision in the UK is unknown. We aimed to evaluate this and estimate the requirements for full implementation of the guidelines including geographical variation. Ancillary aims included surveying the number of CTCA-capable scanners and accredited practitioners in the UK.

Methods

The number of CTCA scans performed annually was surveyed across the National Health Service (NHS). The number of percutaneous coronary interventions performed for stable angina in the NHS in 2015 was applied to a model based on SCOT-HEART (CTCA in patients with suspected angina due to coronary heart disease: an open-label, parallel-group, multicentre trial) data to estimate the requirement for CTCA, for full guideline implementation. Details of CTCA-capable scanners were obtained from manufacturers and formally accredited practitioner details from professional societies.

Results

An estimated 42 340 CTCAs are currently performed annually in the UK. We estimate that 350 000 would be required to fully implement the guidelines. 304 CTCA-capable scanners and 198 accredited practitioners were identified. A marked geographical variation between health regions was observed.

Conclusions

This study provides insight into the scale of increase in the provision of CTCA required to fully implement the updated NICE guidelines. A small specialist workforce and limited number of CTCA-capable scanners may present challenges to service expansion.
Rapid diagnosis of pulmonary tuberculosis and detection of drug resistance by combined simultaneous amplification testing and reverse dot blot
Authors: Chen Yiwen , Zhang Lahong , Hong Liquan , Luo Xian , Chen Juping , Tang Leiming , Chen Jiahuan , Liu Xia , Chen Zhaojun
Published: November 2017

Aims

Making a correct and rapid diagnosis is essential for managing pulmonary tuberculosis (PTB), particularly multidrug-resistant tuberculosis. We aimed to evaluate the efficacy of the combination of simultaneous amplification testing (SAT) and reverse dot blot (RDB) for the rapid detection ofMycobacterium tuberculosis(MTB) and drug-resistant mutants in respiratory samples.

Methods

225 suspected PTB and 32 non-TB pulmonary disease samples were collected. All sputum samples were sent for acid-fast bacilli smear, SAT, culture and drug susceptibility testing (DST) by the BACTECTMMGITTM960 system. 53 PTB samples were tested by both RDB and DNA sequencing to identify drug resistance genes and mutated sites.

Results

The SAT positive rate (64.9%) was higher than the culture positive rate (55.1%), with a coincidence rate of 83.7%. The sensitivity and specificity of SAT for diagnosing PTB were 66.7% and 100%, respectively, while those for culture were 53.9% and 84.2%, respectively. RDB has high sensitivity and specificity in identifying drug resistance genes and mutated sites. The results of RDB correlated well with those of DST and DNA sequencing, with coincidence rates of 92.5% and 98.1%, respectively.

Conclusions

The combination of SAT and RDB is promising for rapidly detecting PTB and monitoring drug resistance in clinical laboratories.
Strength behavior of plain cement concrete subjected to true triaxial compression
Authors: Rukhaiyar Saurav , Sajwan Gaurav , Samadhiya Narendra Kumar
Published: November 2017

True triaxial compression test was conducted on 100 mm × 100 mm × 100 mm cubical sample of plain cement concrete using the true triaxial testing machine. A total of 30 tests were conducted on two concrete mixes having characteristic strengths of 24.39 MPa and 34.67 MPa. The minor and intermediate principal stresses were varied from 2.5 MPa to 10 MPa and 2.5 MPa to 30 MPa respectively. The samples were loaded until failure under the stress rate of 1 MPa/min. The failure mode and direction of fracture planes were observed carefully. It was observed that the ratio of intermediate and minor principal stress had an incremental effect on the strength of the concrete. The results obtained from our experimental study as well as the true triaxial compression test data published in literature has been used to conduct a quantitative evaluation of three commonly used failure criteria presented for the concrete. The three failure criteria considered are Drucker-Prager (DP) criterion, Bresler-Pester (BP) criterion, and Hsieh-Ting-Chen (HTC) criterion. It was observed that for the normal strength concrete, the HTC criterion predicts the strength with least error while for the high strength concrete, the DP criterion gives better predictions. Overall the DP and BP criteria underestimate the strength while the HTC criterion overestimates.
Plasmon modes in Dirac–Schrödinger hybrid electron systems including layer-thickness and exchange-correlation effects
Authors: Van Men Nguyen , Khanh Nguyen Quoc
Published: November 2017

We calculate the plasmon dispersion relation and damping rate of collective excitations in a double-layer system consisting of monolayer graphene and GaAs quantum well at zero temperature including layer-thickness and exchange-correlation effects. We use the generalized random-phase-approximation dielectric function and take into account the nonhomogeneity of the dielectric background of the system. We show that the effects of layer thickness, electron densities, and exchange-correlations are more pronounced for acoustic modes, while the optical branch depends remarkably on dielectric constants of the contacting media.
Obstructions to deforming curves on a 3-fold, III: Deformations of curves lying on a K3 surface
Authors: Nasu Hirokazu
Published: November 2017

We study the deformations of a smooth curve [Formula: see text] on a smooth projective [Formula: see text]-fold [Formula: see text], assuming the presence of a smooth surface [Formula: see text] satisfying [Formula: see text]. Generalizing a result of Mukai and Nasu, we give a new sufficient condition for a first order infinitesimal deformation of [Formula: see text] in [Formula: see text] to be primarily obstructed. In particular, when [Formula: see text] is Fano and [Formula: see text] is [Formula: see text], we give a sufficient condition for [Formula: see text] to be (un)obstructed in [Formula: see text], in terms of [Formula: see text]-curves and elliptic curves on [Formula: see text]. Applying this result, we prove that the Hilbert scheme [Formula: see text] of smooth connected curves on a smooth quartic [Formula: see text]-fold [Formula: see text] contains infinitely many generically non-reduced irreducible components, which are variations of Mumford’s example for [Formula: see text].
Dynamic characteristics of traffic flow with consideration of crossing pedestrians’ behavior at a nonsignalized T-shaped intersection
Authors: Echab H. , Ez-Zahraouy H.
Published: November 2017

In this paper, we present a cellular automata model to depict the traffic characteristics at such a nonsignalized [Formula: see text]-shaped intersection in the presence of pedestrian crossings. The vehicular traffic flow characteristics with different parameters are studied. Throughput, phase diagrams, space-time and density profiles are built to point various traffic states and the phase transition features. The principal finding of the simulation are as follows: (1) The presence of crossing pedestrians has a significant influence on the vehicular traffic and the system performance, (2) The intersection capacity has a close relevance with the state of the weaving section. The smaller the interactions are at the weaving section, the higher the capacity and (3) In order to have a higher system ability, the crosswalk location should not be far from the yield line of the weaving section.
A computational approach to the ample cone of moduli spaces of curves
Authors: Fontanari Claudio , Ghiloni Riccardo , Lella Paolo
Published: November 2017

We present an alternate proof, much quicker and more straightforward than the original one, of the celebrated F-conjecture on the ample cone of the moduli space [Formula: see text] of stable rational curves with [Formula: see text] marked points in the case [Formula: see text].
Stick number of spatial graphs
Authors: Lee Minjung , No Sungjong , Oh Seungsang
Published: November 2017

For a nontrivial knot [Formula: see text], Negami found an upper bound on the stick number [Formula: see text] in terms of its crossing number [Formula: see text] which is [Formula: see text]. Later, Huh and Oh utilized the arc index [Formula: see text] to present a more precise upper bound [Formula: see text]. Furthermore, Kim, No and Oh found an upper bound on the equilateral stick number [Formula: see text] as follows; [Formula: see text]. As a sequel to this research program, we similarly define the stick number [Formula: see text] and the equilateral stick number [Formula: see text] of a spatial graph [Formula: see text], and present their upper bounds as follows; [Formula: see text] [Formula: see text] where [Formula: see text] and [Formula: see text] are the number of edges and vertices of [Formula: see text], respectively, [Formula: see text] is the number of bouquet cut-components, and [Formula: see text] is the number of non-splittable components.
Existence of unilateral, ternary, integral quadratic forms
Authors: Montesinos-Amilibia José María
Published: November 2017

A ternary, integral quadratic form is called unilateral if its associated orbifold [Formula: see text] is orientable. Examples of unilateral forms [Formula: see text] and their associated orbifolds [Formula: see text] are given. The examples are selected to give credit to the conjecture that every form with square-free, prime determinant has a unilateral [Formula: see text]-cover.
Knots having the same Seifert form and primary decomposition of knot concordance
Authors: Kim Taehee
Published: November 2017

We show that for each Seifert form of an algebraically slice knot with nontrivial Alexander polynomial, there exists an infinite family of knots having the Seifert form such that the knots are linearly independent in the knot concordance group and not concordant to any knot with coprime Alexander polynomial. Key ingredients for the proof are Cheeger–Gromov–von Neumann [Formula: see text]-invariants for amenable groups developed by Cha–Orr and polynomial splittings of metabelian [Formula: see text]-invariants.
STRUCTURAL AND ELECTROCHEMICAL PROPERTIES OF THIN LAYERS OF BINARY Ni–Fe ALLOYS ELECTRODEPOSITED BY TWO DIFFERENT BATHS: ACID AND IONIC LIQUID
Authors: MAIZI RAFIK , MEDDOUR ATHMANE , ROUSSE CÉLINE
Published: November 2017

The deposition of Ni–Fe thin layers in boric acid and ionic liquid ([BuMePyr][Tf2N]) baths were successfully prepared. The obtained materials have been characterized by X-ray diffraction (XRD), Energy Dispersive X-ray spectroscopy (EDX) and SEM. Meanwhile, these materials were carried out by chronoamperometry or chronopotentiometry by varying the intensity of the current and the deposition potential. The results indicate that the coatings of Ni–Fe alloys were successfully obtained by electroplating on the copper substrates, and the alloys composition shows irregular behavior with polarization. The nickel content in the samples is in the range of 55–90%, but the iron content ranges from 10–30%, when potential deposits were varied from [Formula: see text]2[Formula: see text]V to [Formula: see text]4[Formula: see text]V vs Ni electrode. The results also showed that the thin layers are monophased; they contain the Ni3Fe phase. Further, SEM images of Ni–Fe alloys show the different shapes of particles.
The asymptotics of the analytic torsion on CR manifolds with S1 action
Authors: Hsiao Chin-Yu , Huang Rung-Tzung
Published: November 2017

Let [Formula: see text] be a compact connected strongly pseudoconvex CR manifold of dimension [Formula: see text], [Formula: see text] with a transversal CR [Formula: see text]-action on [Formula: see text]. We introduce the Fourier components of the Ray–Singer analytic torsion on [Formula: see text] with respect to the [Formula: see text]-action. We establish an asymptotic formula for the Fourier components of the analytic torsion with respect to the [Formula: see text]-action. This generalizes the asymptotic formula of Bismut and Vasserot on the holomorphic Ray–Singer torsion associated with high powers of a positive line bundle to strongly pseudoconvex CR manifolds with a transversal CR [Formula: see text]-action.
SOCIAL CONFLICT AND SOCIAL INNOVATION
Authors: KWOK NGAI KUEN ALVIN
Published: November 2017

While the spot light in recent years is focusing on the merits of social enterprises and their contributions to social innovation, this paper tries to look from a different angle on social innovation — on the relationship between social conflict and social innovation. From the perspective of social change, social conflict will inevitably bring about change even though forces of resistance to change may also exist at the same time. No matter such change is on the positive or negative side, and no matter how significant or immaterial it is, social change is manifested in the form of new social practices, norms, new values, or even new culture. Starting from an attempt on conceptualization of social innovation, this paper argues that social conflict can bring forth social innovation, provided that the former meets essential criteria and conditions. It urges for an enabling environment that will foster social conflicts into social innovations. It further argues that a cultural turn may be the keystone for such a change to occur.
GENDERED BoP HYGIENE MARKETS IN RURAL INDIA: A CASE STUDY OF SOCIAL ENTREPRENEURSHIP AND SOCIAL INNOVATION
Authors: SINGH SUKHPAL
Published: November 2017

Water scarcity and non-existent or poor sanitation have special implications for the poor in a rural context of a developing country such as India, especially in the case of women due to their personal hygiene needs. The penetration of sanitary napkins is very low in Indian villages for reasons such as the high cost of branded napkins, availability, and cultural barriers. Over 88% of rural women use unhygienic alternatives during menstruation, with 77% using a piece of old cloth and many others nothing at all. These practices lead to a deterioration in health of the mother as well as the child and, sometimes, the death of the mother. Furthermore, a large proportion of girls in India do not go to school during their menstruation period, for an average of 4–5 days every month, and at least 23% of girls drop out of school when they start menstruating. Adult women cut down on their productive day-to-day activities. Menstruating lower-income women also have to follow certain social exclusion norms and treat it as a purely private matter as it is considered a social taboo. The access to personal reproductive hygiene products and services thus becomes indispensable in terms of addressing hygiene and sanitation needs. Furthermore, this is more of a developmental/social venture rather than just pure rural marketing. This paper examines the issue from a social enterprise and social innovation perspective in order to understand the issues involved in changing the situation. It examines the case of a social venture in India (Goonj) which has attempted to deal with this market in terms of its approach, product design, market creation, performance, issues faced, and impact made. The paper attempts to infer lessons for making social entrepreneurship and social innovations work in developing country health and hygiene contexts in the form of a Bottom of Pyramid (BoP) market solution.
New molecular target insights about protein kinases of the Plasmodium falciparum. Using molecular docking and DFT-based reactivity descriptors
Authors: Morales-Bayuelo Alejandro
Published: November 2017

Currently, there is increasing interest in the potential of malaria inhibitors in Plasmodium falciparum activity. In this work, is propose a possible alternative to classifying 154 antimalarials, with P. falciparum activity. These antimalarials were synthesized by the Chibale’s group ( http://www.kellychibaleresearch.uct.ac.za/ ), with the goal of finding new insights on the binding pocket of the protein kinase PfPK5, PfPK7, PfCDPK1, PfCDPK4, PfMAP1, and PfPK6 of the malaria parasite. However, there is only information about crystallography of PfPK5 and PfPK7. The protein kinases PfCDPK1, PfCDPK4, PfMAP1, and PfPK6 were modeled using molecular homology. The validation used shows that our homology models can be an alternative for the protein kinases from P. falciparum, unknown today. The antimalarials were classified by taking into account the interactions in the hinge zone. These ligands bind to the kinase through the formation of one of two hydrogen bonds, with the backbone residues of the hinge region connecting the kinase N- and C-terminal loops. These interactions were supported by a reactivity chemistry analysis, using global chemical reactivity descriptors such as chemical potential, hardness, softness, electrophilicity, and the Fukui functions as local reactivity descriptors, within the Density Functional Theory (DFT) context.
A tale of two velocities: Threading versus slicing
Authors: Gharechahi Razieh , Nouri-Zonoz Mohammad , Tavanfar Alireza
Published: November 2017

One of the important quantities in cosmology and astrophysics is the 3-velocity of an object. Specifically, when the gravitational fields are strong, one should require the employment of general relativity both in its definition and measurement. Looking into the literature for GR-based definitions of 3-velocity, one usually finds different ad hoc definitions applied according to the case under consideration. Here, we introduce and analyze systematically the two principal definitions of 3-velocity assigned to a test particle following the timelike trajectories in stationary spacetimes. These definitions are based on the [Formula: see text] (threading) and [Formula: see text] (slicing) spacetime decomposition formalisms and defined relative to two different sets of observers. After showing that Synge’s definition of spatial distance and 3-velocity is equivalent to those defined in the [Formula: see text] (threading) formalism, we exemplify the differences between these two definitions by calculating them for particles in circular orbits in axially symmetric stationary spacetimes. Illustrating its geometric nature, the relative linear velocity between the corresponding observers is obtained in terms of the spacetime metric components. Circular particle orbits in the Kerr spacetime, as the prototype and the most well known of stationary spacetimes, are examined with respect to these definitions to highlight their observer-dependent nature.

We also examine the Kerr-NUT spacetime in which the NUT parameter, contributing to the off-diagonal terms in the metric, is mainly interpreted not as a rotation parameter but as a gravitomagnetic monopole charge. Finally, in a specific astrophysical setup which includes rotating black holes, it is shown how the local velocity of an orbiting star could be related to its spectral line shifts measured by distant observers.
Symmetrical or Non-Symmetrical Debonds at Fiber–Matrix Interfaces: A Study by BEM and Finite Fracture Mechanics on Elastic Interfaces
Authors: Muñoz-Reja Mar , Távara Luis , Mantič Vladislav
Published: November 2017

A recently proposed criterion is used to study the behavior of debonds produced at a fiber–matrix interface. The criterion is based on the Linear Elastic–(Perfectly) Brittle Interface Model (LEBIM) combined with a Finite Fracture Mechanics (FFM) approach, where the stress and energy criteria are suitably coupled. Special attention is given to the discussion about the symmetry of the debond onset and growth in an isolated single fiber specimen under uniaxial transverse tension. A common composite material system, glass fiber–epoxy matrix, is considered. The present methodology uses a two-dimensional (2D) Boundary Element Method (BEM) code to carry out the analysis of interface failure. The present results show that a non-symmetrical interface crack configuration (debonds at one side only) is produced by a lower critical remote load than the symmetrical case (debonds at both sides). Thus, the non-symmetrical solution is the preferred one, which agrees with the experimental evidences found in the literature.
The backward bifurcation of a model for malaria infection
Authors: Wang Juan , Li Xue-Zhi , Bhattacharya Souvik
Published: November 2017

In this paper, an epidemic model of a vector-borne disease, namely, malaria, is considered. The explicit expression of the basic reproduction number is obtained, the local and global asymptotical stability of the disease-free equilibrium is proved under certain conditions. It is shown that the model exhibits the phenomenon of backward bifurcation where the stable disease-free equilibrium coexists with a stable endemic equilibrium. Further, it is proved that the unique endemic equilibrium is globally asymptotically stable under certain conditions.
Bio-inspired computational heuristics to study models of HIV infection of CD4+ T-cell
Authors: Raja Muhammad Asif Zahoor , Asma Kiran , Aslam Muhammad Saeed
Published: November 2017

In this work, biologically-inspired computing framework is developed for HIV infection of CD4[Formula: see text] T-cell model using feed-forward artificial neural networks (ANNs), genetic algorithms (GAs), sequential quadratic programming (SQP) and hybrid approach based on GA-SQP. The mathematical model for HIV infection of CD4[Formula: see text] T-cells is represented with the help of initial value problems (IVPs) based on the system of ordinary differential equations (ODEs). The ANN model for the system is constructed by exploiting its strength of universal approximation. An objective function is developed for the system through unsupervised error using ANNs in the mean square sense. Training with weights of ANNs is carried out with GAs for effective global search supported with SQP for efficient local search. The proposed scheme is evaluated on a number of scenarios for the HIV infection model by taking the different levels for infected cells, natural substitution rates of uninfected cells, and virus particles. Comparisons of the approximate solutions are made with results of Adams numerical solver to establish the correctness of the proposed scheme. Accuracy and convergence of the approach are validated through the results of statistical analysis based on the sufficient large number of independent runs.
Improving Write Performance and Extending Endurance of Object-Based NAND Flash Devices
Authors: Guo Jie , Min Chuhan , Cai Tao , Chen Yiran
Published: November 2017

Write amplification is a major cause of performance and endurance degradations in NAND flash-based storage systems. In an object-based NAND flash device (ONFD), two causes of write amplification are onode partial update and cascading update. Here, onode is a type of small-sized object metadata, and multiple onodes are stored in one NAND flash page. Updating one onode invokes partial page update (i.e., onode partial update), incurring unnecessary migration of the un-updated data. Cascading update denotes updating object metadata in a cascading manner due to object data update or migration. Although there are only several bytes that need to be updated in the object metadata, one or more pages have to be re-written accordingly. In this work, we propose a system design to alleviate the write amplification issue in the object-based NAND flash device. The proposed design includes (1) a multi-level garbage collection technique to minimize unnecessary data migration incurred by onode partial update and (2) a B+ table tree, Semantics-Aware Flexible (SAF) data layout, and selective cache design to reduce the write operations associated with cascading update. To guarantee system consistency, we also propose a power failure handling technique. Experiment results show that our proposed design can achieve up to 20% write reduction compared to the best states of the art.
SUPA
Authors: Kim Dongjin , Park Kyu Ho , Youn Chan-Hyun
Published: November 2017

To design the write buffer and flash translation layer (FTL) for a solid-state drive (SSD), previous studies have tried to increase overall SSD performance by parallel I/O and garbage collection overhead reduction. Recent works have proposed pattern-based managements, which uses the request size and read- or write-intensiveness to apply different policies to each type of data. In our observation, the locations of read and write requests are closely related, and the pattern of each type of data can be changed. In this work, we propose SUPA, a single unified read-write buffer and pattern-change-aware FTL on multi-channel SSD architecture. To increase both read and write hit ratios on the buffer based on locality, we use a single unified read-write buffer for both clean and dirty blocks. With proposed buffer, we can increase buffer hit ratio up to 8.0% and reduce 33.6% and 7.5% of read and write latencies, respectively. To handle pattern-changed blocks, we add a pattern handler between the buffer and the FTL, which monitors channel status and handles data by applying one of the two different policies according to the pattern changes. With pattern change handling process, we can reduce 1.0% and 15.4% of read and write latencies, respectively. In total, our evaluations show that SUPA can get up to 2.0 and 3.9 times less read and write latency, respectively, without loss of lifetime in comparison to previous works.
Metatation
Authors: Mehta Hrim , Bradley Adam , Hancock Mark , Collins Christopher
Published: November 2017

In the domain of literary criticism, many critics practice
close reading
, annotating by hand while performing a detailed analysis of a single text. Often this process employs the use of external resources to aid analysis. In this article, we present a study and subsequent tool design focused on leveraging a critic’s annotations as implicit interactions for initiating context-specific computational support that automatically searches external resources. We observed 14 poetry critics performing a close reading, revealing a set of cognitive practices supported through free-form annotation that have not previously been discussed in this context. We used guidelines derived from our study to design a tool, Metatation, which uses a pen-and-paper system with a peripheral display to utilize reader annotations as underspecified interactions to augment close reading. By turning paper-based annotations into implicit queries, Metatation provides relevant supplemental information in a just-in-time manner and acts as a bridge between close and distant reading.
Linear Time Membership in a Class of Regular Expressions with Counting, Interleaving, and Unordered Concatenation
Authors: Colazzo Dario , Ghelli Giorgio , Sartiani Carlo
Published: November 2017

Regular Expressions (REs) are ubiquitous in database and programming languages. While many applications make use of REs extended with
interleaving
(
shuffle
) and
unordered concatenation
operators, this extension badly affects the complexity of basic operations, and, especially, makes
membership
NP-hard, which is unacceptable in most practical scenarios.

In this article, we study the problem of membership checking for a restricted class of these extended REs, called
conflict-free REs
, which are expressive enough to cover the vast majority of real-world applications. We present several polynomial algorithms for membership checking over conflict-free REs. The algorithms are all polynomial and differ in terms of adopted optimization techniques and in the kind of supported operators. As a particular application, we generalize the approach to check membership of Extensible Markup Language trees into a class of EDTDs (Extended Document Type Definitions) that models the crucial aspects of DTDs (Document Type Definitions) and XSD (XML Schema Definitions) schemas.

Results about an extensive experimental analysis validate the efficiency of the presented membership checking techniques.
Modeling and Simulating the Web of Things from an Information Retrieval Perspective
Authors: Manta-Caro Cristyan , Fernández-Luna Juan M.
Published: November 2017

Internet and Web technologies have changed our lives in ways we are not yet fully aware of. In the near future, Internet will interconnect more than 50 billion things in the real world, nodes will sense billions of features and properties of interest, and things will be represented by web-based, bi-directional services with highly dynamic content and real-time data. This is the new era of the
Internet and the Web of Things
. Since the emergence of such paradigms implies the evolution and integration of the systems with which they interact, it is essential to develop abstract models for representing and simulating the Web of Things in order to establish new approaches. This article describes a Web of Things model based on a structured XML representation. We also present a simulator whose ultimate goal is to encapsulate the expected dynamics of the Web of Things for the future development of information retrieval (IR) systems. The simulator generates a real-time collection of XML documents containing spatio-temporal contexts and textual and sensed information of highly dynamic dimensions. The simulator is characterized by its flexibility and versatility for representing real-world scenarios and offers a unique perspective for information retrieval. In this article, we evaluate and test the simulator in terms of its performance variables for computing resource consumption and present our experimentation with the simulator on three real scenarios by considering the generation variables for the IR document collection.
A Survey of Presence and Related Concepts
Authors: Skarbez Richard , Brooks, Jr. Frederick P. , Whitton Mary C.
Published: November 2017

The presence construct, most commonly defined as the sense of “being there,” has driven research and development of virtual environments (VEs) for decades. Despite that, there is not widespread agreement on how to define or operationalize this construct. The literature contains many different definitions of presence and many proposed measures for it. This article reviews many of the definitions, measures, and models of presence from the literature. We also review several related constructs, including social presence, copresence, immersion, agency, transportation, reality judgment, and embodiment. In addition, we present a meta-analysis of existing presence models and propose a model of presence informed by Slater’s Place Illusion and Plausibility Illusion constructs.
Cache Exclusivity and Sharing
Authors: Ye Chencheng , Ding Chen , Luo Hao , Brock Jacob , Chen Dong , Jin Hai
Published: November 2017

A problem on multicore systems is cache sharing, where the cache occupancy of a program depends on the cache usage of peer programs. Exclusive cache hierarchy as used on AMD processors is an effective solution to allow processor cores to have a large private cache while still benefitting from shared cache. The shared cache stores the “victims” (i.e., data evicted from private caches). The performance depends on how victims of co-run programs interact in shared cache.

This article presents a new metric called the
victim footprint
(VFP). It is measured once per program in its solo execution and can then be combined to compute the performance of any exclusive cache hierarchy, replacing parallel testing with theoretical analysis. The work evaluates the VFP by using it to analyze cache sharing by parallel mixes of sequential programs, comparing the accuracy of the theory to hardware counter results, and measuring the benefit of exclusivity-aware analysis and optimization.
Energy-Efficient Compilation of Irregular Task-Parallel Loops
Authors: Shrivastava Rahul , Nandivada V. Krishna
Published: November 2017

Energy-efficient compilation is an important problem for multi-core systems. In this context, irregular programs with task-parallel loops  present interesting challenges: the threads with lesser work-loads (
non-critical
-threads) wait at the join-points for the thread with maximum work-load (
critical
-thread); this leads to significant energy wastage. This problem becomes more interesting in the context of multi-socket-multi-core (MSMC) systems, where different sockets may run at different frequencies, but all the cores connected to a socket run at a single frequency. In such a configuration, even though the load-imbalance among the cores may be significant, an MSMC-oblivious technique may miss the opportunities to reduce energy consumption, if the load-imbalance across the sockets is minimal. This problem becomes further challenging in the presence of mutual-exclusion, where scaling the frequencies of a socket executing the non-critical-threads can impact the execution time of the critical-threads. In this article, we propose a scheme (X10Ergy) to obtain energy gains with minimal impact on the execution time, for task-parallel languages, such as X10, HJ, and so on. X10Ergy takes as input a loop-chunked program (parallel-loop iterations divided into chunks and each chunk is executed by a unique thread). X10Ergy follows a mixed compile-time + runtime approach that (i) uses static analysis to efficiently compute the work-load of each chunk at runtime, (ii) computes the “remaining” work-load of the chunks running on the cores of each socket at regular intervals and tunes the frequency of the sockets accordingly, (iii) groups the threads into different sockets (based on the remaining work-load of their respective chunks), and (iv) in the presence of atomic-blocks, models the effect of frequency-scaling on the critical-thread. We implemented X10Ergy for X10 and have obtained encouraging results for the IMSuite kernels.
Optimal Repair Layering for Erasure-Coded Data Centers
Authors: Hu Yuchong , Li Xiaolu , Zhang Mi , Lee Patrick P. C. , Zhang Xiaoyang , Zhou Pan , Feng Dan
Published: November 2017

Repair performance in hierarchical data centers is often bottlenecked by cross-rack network transfer. Recent theoretical results show that the cross-rack repair traffic can be minimized through repair layering, whose idea is to partition a repair operation into inner-rack and cross-rack layers. However, how repair layering should be implemented and deployed in practice remains an open issue. In this article, we address this issue by proposing a practical repair layering framework called
DoubleR
. We design two families of practical double regenerating codes (DRC), which not only minimize the cross-rack repair traffic but also have several practical properties that improve state-of-the-art regenerating codes. We implement and deploy DoubleR atop the Hadoop Distributed File System (HDFS) and show that DoubleR maintains the theoretical guarantees of DRC and improves the repair performance of regenerating codes in both node recovery and degraded read operations.
CosaFS
Authors: Zeng Lingfang , Zhang Zehao , Wang Yang , Feng Dan , Kent Kenneth B.
Published: November 2017

In this article, we design and implement a cooperative shingle-aware file system, called
CosaFS
, on heterogeneous storage devices that mix solid-state drives (SSDs) and shingled magnetic recording (SMR) technology to improve the overall performance of storage systems. The basic idea of CosaFS is to classify objects as hot or cold objects based on a proposed Lookahead with Recency Weight scheme. If an object is identified as a hot (small) object, then it will be served by SSD. Otherwise, cold (large) objects are stored on SMR. For an SMR, large objects can be accessed in large sequential blocks, rendering the performance of their accesses comparable with that of accessing the same large sequential blocks as if they were stored on a hard drive. Small objects, such as inodes and directories, are stored on the SSD where “seeks” for such objects are nearly free. With thorough empirical studies, we demonstrate that CosaFS, as a cooperative shingle-aware file system, with metadata separation and cache-assistance, is a very effective way to handle the disk-based data demanded by the shingled writes and outperforms the device- and host-side shingle-aware file systems in terms of throughput, IOPS, and access latency as well.
Short-term metformin and exercise training effects on strength, aerobic capacity, glycemic control, and mitochondrial function in children with burn injury
Authors: Rivas Eric , Herndon David N. , Porter Craig , Meyer Walter , Suman Oscar E.
Published: November 2017

Severely burned children experience a chronic state of sympathetic nervous system activation that is associated with hypermetabolic/cardiac stress and muscle wasting. Metformin, a diabetes medication, helps control hyperglycemia in obese diabetic populations, and exercise has been shown to improve exercise strength and aerobic exercise capacity after severe burns. However, whether exercise improves glycemic control in burned children and whether combining exercise and metformin improves outcomes to a greater degree than exercise alone are unknown. We tested the hypothesis that a 6-wk exercise program combined with short-term metformin administration (E + M) improves aerobic and strength exercise capacity to a greater degree than exercise and placebo (E), while improving glucose tolerance and muscle metabolic function. We found that, before exercise training, the metformin group compared with the placebo group had attenuated mitochondrial respiration (pmol·s−1·mg−1) for each state: state 2 (−22.5 ± 3), state 3 (−42.4 ± 13), and oxphos (−58.9 ± 19) ( P ≤ 0.02, M vs. E + M group for each state). However, in the E + M group, exercise increased mitochondrial respiration in each state ( P ≤ 0.05), with respiration being comparable to that in the E group (each P > 0.05). In both groups, exercise induced comparable improvements in strength (change from preexercise, Δ1.6 ± 0.6 N-M·kgLBM) and V̇o2peak (Δ9 ± 7 mlO2·kgLBM) as well as fasting glucose (Δ19.3 ± 13 mg·dl) and glucose AUC (Δ3402 ± 3674 mg·dl−1·min−1), as measured by a 75-g OGTT (all P ≤ 0.03). Exercise reduced resting energy expenditure in E + M (Δ539 ± 480 kcal/24 h, P < 0.01) but not E subjects ( P = 0.68). Both groups exhibited reduced resting heart rate (Δ30 ± 23 beats/min, P ≤ 0.02). These data indicate that short-term metformin combined with exercise provides no further improvement beyond that of exercise alone for strength, exercise capacity, and glycemic control.
Androgen signaling expands β-cell mass in male rats and β-cell androgen receptor is degraded under high-glucose conditions
Authors: Harada Naoki , Yoda Yasuhiro , Yotsumoto Yusuke , Masuda Tatsuya , Takahashi Yuji , Katsuki Takahiro , Kai Kenji , Shiraki Nobuaki , Inui Hiroshi , Yamaji Ryoichi
Published: November 2017

A deficient pancreatic β-cell mass increases the risk of type 2 diabetes mellitus. Here, we investigated the effects of testosterone on the development of pancreatic β-cell mass in male rats. The β-cell mass of male rats castrated at 6 wk of age was reduced to ~30% of that of control rats at 16 wk of age, and castration caused glucose intolerance. Loss of β-cell mass occurred because of decreases in islet density per pancreas and β-cell cluster size. Castration was negatively associated with the number of Ki-67-positive β-cells and positively associated with the number of TUNEL-positive β-cells. These β-cell changes could be prevented by testosterone treatment. In contrast, castration did not affect β-cell mass in male mice. Androgen receptor (AR) localized differently in mouse and rat β-cells. Testosterone enhanced the viability of INS-1 and INS-1 #6, which expresses high levels of AR, in rat β-cell lines. siRNA-mediated AR knockdown or AR antagonism with hydroxyflutamide attenuated this enhancement. Moreover, testosterone did not stimulate INS-1 β-cell viability under high d-glucose conditions. In INS-1 β-cells, d-glucose dose dependently (5.5–22.2 mM) downregulated AR protein levels both in the presence and absence of testosterone. The intracellular calcium chelator (BAPTA-AM) could prevent this decrease in AR expression. AR levels were also reduced by a calcium ionophore (A23187), but not by insulin, in the absence of the proteasome inhibitor MG132. Our results indicate that testosterone regulates β-cell mass, at least in part, by AR activation in the β-cells of male rats and that the β-cell AR is degraded under hyperglycemic conditions.
Insulin secretory effect of sitagliptin: assessment with a hyperglycemic clamp combined with a meal challenge
Authors: Shankar Sudha S. , Shankar R. Ravi , Mixson Lori A. , Miller Deborah L. , Steinberg Helmut O. , Beals Chan R. , Kelley David E.
Published: November 2017

Sitagliptin, a dipeptidyl peptidase-IV inhibitor (DPP-4), sustains activity of the incretin hormones GLP-1 and GIP and improves hyperglycemia in Type 2 diabetes mellitus (T2DM). It has however proven challenging to quantify the effect of sitagliptin on rates of insulin secretion (ISR) during a prandial challenge. The tight feedback governance of ISR by plasma glucose means that in the face of treatment-related lowering of postprandial glycemia, corresponding stimulation of ISR is lessened. We postulated that sustaining a stable level of moderate hyperglycemia before and during a meal challenge (MC) would be a platform that enables greater clarity to assess the effect of sitagliptin on ISR and an approach that could be valuable to evaluate novel targets that increase insulin secretion directly and by augmenting incretins. A hyperglycemic clamp (HGC) at 160 mg/dl was conducted in 12 healthy volunteers (without diabetes) for 6 h; 3 h into the HGC, MC was administered while maintaining stable hyperglycemia of the HGC for an additional 3 h. Modeling of C-peptide response was used to calculate ISR. In crossover design of three periods (sitagliptin twice and placebo once), the effect of sitagliptin vs. placebo on ISR and the reproducibility of the response to sitagliptin were assessed. Sitagliptin increased ISR compared with placebo by 50% and 20% during the HGC alone and the HGC-MC phases, respectively ( P < 0.001 for both). There was an associated significant treatment-based increase in circulating insulin, as well as active levels of GLP-1. Robust reproducibility of the sitagliptin-mediated ISR response was observed; the intraclass correlation value was 0.94. The findings delineate the effect of sitagliptin to stimulate insulin secretion, and these benchmark data also demonstrate that an HGC-MC can be a useful platform for interrogating therapeutic targets that could potentially modulate ISR via direct action on beta-cells as well as by augmenting release or action of incretins.
Hepatoma-Derived Growth Factor Secreted from Mesenchymal Stem Cells Reduces Myocardial Ischemia-Reperfusion Injury
Authors: Zhou Yu , Chen Panpan , Liu Qingnian , Wang Yingchao , Zhang Ling , Wu Rongrong , Chen Jinghai , Yu Hong , Zhu Wei , Hu Xinyang , Wang Jian-An
Published: November 2017

Objectives. The present study aimed to explore the major factors that account for the beneficial effects of mesenchymal stem cells (MSCs). Methods. Using isobaric tags for relative and absolute quantitation method, hepatoma-derived growth factor (HDGF) was identified as an important factor secreted by MSCs, but not by cardiac fibroblasts (CFs). The protective effects of conditioned medium (CdM) from MSCs or CFs were tested by using either H9C2 cells that were exposed by hypoxia-reoxygenation (H/R) insult or an in vivo mouse model of myocardial ischemia-reperfusion. Results. Compared to CF-CdM, MSC-CdM conferred protection against reperfusion injury. CdM obtained from MSCs that were treated with HDGF-targeted shRNA failed to offer any protection in vitro. In addition, administration of recombinant HDGF alone recapitulated the beneficial effects of MSC-CdM, which was associated with increased protein kinase C epsilon (PKCε) phosphorylation, enhanced mitochondria aldehyde dehydrogenase family 2 activity, and decreased 4-hydroxy-2-nonenal accumulation. A significant decrease in infarct size and ameliorated cardiac dysfunction was achieved by administration of HDGF in wild-type mice, which was absent in PKCε dominant negative mice, indicating the essential roles of PKCε in HDGF-mediated protection. Conclusions. HDGF secreted from MSCs plays a key role in the protection against reperfusion injury through PKCε activation.