bluuebunny/crossref_metadata_2025 huggingface dataset:
Analyzing the Tradeoffs Between Economies of Scale, Time-Value of Money, and Flexibility in Design Under Uncertainty: Study of Centralized Versus Decentralized Waste-to-Energy Systems
Authors: Cardin Michel-Alexandre , Hu Junfei
Published: August 2015

This paper presents and applies a simulation-based methodology to assess the value of flexible decentralized engineering systems design (i.e., the ability to flexibly expand the capacity in multiple sites over time and space) under uncertainty. This work differs from others by analyzing explicitly the tradeoffs between economies of scale (EoS)—which favors designing large capacity upfront to reduce unit cost and accommodate high anticipated demand—and the time value of money—which favors deferring capacity investments to the future and deploying smaller modules to reduce unit cost. The study aims to identify the best strategies to design and deploy the capacity of complex engineered systems over time and improve their economic lifecycle performance in the face of uncertainty by exploiting the idea of flexibility. This study is illustrated using a waste-to-energy (WTE) system operated in Singapore. The results show that a decentralized design with the real option to expand the capacity in different locations and times improves the expected net present value (ENPV) by more than 30% under the condition of EoS  α  = 0.8 and discount rate λ   = 8%, as compared to a fixed centralized design. The results also indicate that a flexible decentralized design outperforms other rigid designs under certain circumstances since it not only reduces transportation costs but also takes advantage of flexibility, such as deferring investment and avoiding unnecessary capacity deployment. The modeling framework and results help designers and managers better compare centralized and decentralized design alternatives facing significant uncertainty. The proposed method helps them analyze the value of flexibility (VOF) in small-scale urban environments, while considering explicitly the tradeoffs between EoS and the time-value of money.
Experimental Analysis of a Small-Scale Flowing Electrolyte–Direct Methanol Fuel Cell Stack
Authors: Kablou Yashar , Cruickshank Cynthia A. , Matida Edgar
Published: August 2015

A small-scale five-cell flowing electrolyte–direct methanol fuel cell (FE-DMFC) stack with U-type manifold configuration and parallel serpentine flow bed design was studied experimentally. The active area of a single cell was approximately 25 cm2. For every stack cell, diluted sulphuric acid was used as the flowing electrolyte (FE) which was circulated through a porous medium placed between two Nafion® 115 polymer electrolyte membranes. The stack performance was studied over a range of several operating conditions, such as temperature (50–80 °C), FE flow rate (0–17.5 ml/min), methanol concentration (0.5–4.0 M), and methanol solution flow rate (10–20 ml/min). In addition, the stack cell to cell voltage variations and the effects of the FE stream interruption on the output voltage were investigated at various operating loads. Experimental results showed that utilization of the FE effectively reduced methanol crossover and improved the stack power output. It was found that increasing the FE flow rate enhanced the stack capability to operate at higher inlet methanol concentrations without any degradation to the performance. The results also demonstrated that the stack power output can be directly controlled by regulating the FE stream especially at high operating currents.
Minimum Weight Design for Toroidal Shells With Strengthening Component
Authors: Truong Vu Vu
Published: August 2015

This article presents an approach to the minimum weight design for toroidal shells with strengthening component subject to internal pressure. The optimal shape is obtained by adjusting the geometry and wall thickness of the cross section associated with the thickness and position of the strengthening component. Constraints include first yield pressure, plastic pressures, plastic instability pressure, and internal volume of toroid. The weight saving can reach over 70% in some toroid configurations. The comparison of two optimization methods shows that differential evolution (DE) slightly outperforms particle swarm optimization (PSO) in the majority of investigated cases.
Segmented slant hole collimator for stationary cardiac SPECT: Monte Carlo simulations
Authors: Mao Yanfei , Yu Zhicong , Zeng Gengsheng L.
Published: August 2015

Purpose:

This work is a preliminary study of a stationary cardiac SPECT system. The goal of this research is to propose a stationary cardiac SPECT system using segmented slant‐hole collimators and to perform computer simulations to test the feasibility. Compared to the rotational SPECT, a stationary system has a benefit of acquiring temporally consistent projections. The most challenging issue in building a stationary system is to provide sufficient projection view‐angles.

Methods:

A gate (geant4 application for tomographic emission) Monte Carlo model was developed to simulate a two‐detector stationary cardiac SPECT that uses segmented slant‐hole collimators. Each detector contains seven segmented slant‐hole sections that slant to a common volume at the rotation center. Consequently, 14 view‐angles over 180° were acquired without any gantry rotation. The NCAT phantom was used for data generation and a tailored maximum‐likelihood expectation‐maximization algorithm was used for image reconstruction. Effects of limited number of view‐angles and data truncation were carefully evaluated in the paper.

Results:

Simulation results indicated that the proposed segmented slant‐hole stationary cardiac SPECT system is able to acquire sufficient data for cardiac imaging without a loss of image quality, even when the uptakes in the liver and kidneys are high. Seven views are acquired simultaneously at each detector, leading to 5‐fold sensitivity gain over the conventional dual‐head system at the same total acquisition time, which in turn increases the signal‐to‐noise ratio by 19%. The segmented slant‐hole SPECT system also showed a good performance in lesion detection. In our prototype system, a short hole‐length was used to reduce the dead zone between neighboring collimator segments. The measured sensitivity gain is about 17‐fold over the conventional dual‐head system.

Conclusions:

The gate Monte Carlo simulations confirm the feasibility of the proposed stationary cardiac SPECT system with segmented slant‐hole collimators. The proposed collimator consists of combined parallel and slant holes, and the image on the detector is not reduced in size.
Structure of a yeast spliceosome at 3.6-angstrom resolution
Authors: Yan Chuangye , Hang Jing , Wan Ruixue , Huang Min , Wong Catherine C. L. , Shi Yigong
Published: August 2015

Structure and function of the spliceosome

When RNA is transcribed from DNA in the eukaryotic cell nucleus, the initial transcript includes noncoding introns that must be spliced out. This splicing is done by a complex macromolecular machine, the spliceosome, which comprises five small nuclear RNAs and more than 100 associated proteins. Now, two papers reveal insights into the structure and function of the yeast spliceosome. Yan
et al.
describe a high-resolution structure determined by electron microscopy of a spliceosome complex comprising four RNAs and 37 proteins. Hang
et al.
focus on the catalytic site and show how protein components anchor the transcribed RNA and allow sufficient flexibility to deliver RNA components involved in catalyzing the splicing reaction.

Science
, this issue pp.
1182
and
1191
Easy View Care Maps as an alternative to the traditional specialist to GP clinic letter
Authors: Jaboli Maria Francesca , Rayne Timothy , Durcan Colette , Mason Isobel , Epstein Owen
Published: August 2015

Introduction

In most UK hospitals, clinical episodes are recorded with a letter sent to the referring general practitioners (GPs). This requires dictation, typing, proof-reading, correction, printing, sign-off and posting. We have used a mind map template to record the patient journey. We evaluated the GP responses to these Easy View Care Maps (EVCMs) and the cost comparison with the traditional GP letter.

Methods

An EVCM was prepared by a secretary using information available from the GP referral. The draft EVCM was available for the clinician to complete during the consultation with the patient. Three completed EVCMs were printed: one to be incorporated into the patient's notes; the second to be given to the patient; and a third copy posted to the GP. At follow-up, the EVCM was modified to reflect results. GP responses to EVCMs were sought by a postal questionnaire sent to 266 GPs. A comparative cost analysis was performed.

Results

Over 10 months, 568 EVCMs were used as the sole source of information recorded for the hospital file, patient and GP. The mean turnaround time for a dictated letter is 5.2 days while EVCM generation is immediate. Ninety per cent of GPs reported that they received the necessary information with 71% indicating acceptance as an alternative to the traditional letter. Net annual departmental saving was £31 344.

Conclusions

EVCMs offer a new visual representation of the patient's journey. They are easy to follow and expose the clinician's thought processes. They provide an intuitive record at low cost.
Human trafficking and health: a cross-sectional survey of NHS professionals’ contact with victims of human trafficking
Authors: Ross Claire , Dimitrova Stoyanka , Howard Louise M , Dewey Michael , Zimmerman Cathy , Oram Siân
Published: August 2015

Objectives

(1) To estimate the proportion of National Health Service (NHS) professionals who have come into contact with trafficked people and (2) to measure NHS professionals’ knowledge and confidence to respond to human trafficking.

Design

A cross-sectional survey.

Setting

Face-to-face mandatory child protection and/or vulnerable adults training sessions at 10 secondary healthcare provider organisations in England, and meetings of the UK College of Emergency Medicine.

Participants

782/892 (84.4%) NHS professionals participated, including from emergency medicine, maternity, mental health, paediatrics and other clinical disciplines.

Measures

Self-completed questionnaire developed by an expert panel. Questionnaire asks about prior training and contact with potential victims of trafficking, perceived and actual human trafficking knowledge, confidence in responding to human trafficking, and interest in future human trafficking training.

Results

13% participants reported previous contact with a patient they knew or suspected of having been trafficked; among maternity services professionals this was 20.4%. However, 86.8% (n=679) reported lacking knowledge of what questions to ask to identify potential victims and 78.3% (n=613) reported that they had insufficient training to assist trafficked people. 71% (n=556), 67.5% (n=528) and 53.4% (n=418) lacked confidence in making appropriate referrals for men, women and children, respectively, who had been trafficked. 95.3% (n=746) of respondents were unaware of the scale of human trafficking in the UK, and 76.5% (n=598) were unaware that calling the police could put patients in more danger. Psychometric analysis showed that subscales measuring perceived knowledge, actual knowledge and confidence to respond to human trafficking demonstrated good internal consistency (Cronbach's αs 0.93, 0.63 and 0.64, respectively) and internal correlations.

Conclusions

NHS professionals working in secondary care are in contact with potential victims of human trafficking, but lack knowledge and confidence in how to respond appropriately. Training is needed, particularly for maternity staff, on how to identify and respond to victims’ needs, including through making safe referrals.
An improved estimator for the sampling error of local competition variables
Authors: Antón-Fernández Clara , Froese Robert E.
Published: August 2015

We present a revised estimator for the sampling error of local competition variables that builds on the conceptual framework given by Stage and Wykoff (Stage, A.R., and Wykoff, W.R. For. Sci. 44(2): 224–238, 1998). Accurate estimation of the sampling error of local competition variables is a requisite for most approaches that correct the effects of measurement error in model fitting and application. Our revision addresses the bias inherent in Stage and Wykoff’s estimator due to the overlapping of random samples that are constrained to include a subject tree. We also argue that the adjustment that Stage and Wykoff used to account for the absence of treeless plots (zero truncation) is unnecessary. We illustrate the performance of the new estimator and the estimator of Stage and Wykoff through simulation. For a hypothetical Poisson forest (800 trees·ha−1; mean diameter at breast height, 9.8 cm), bias is negligible for the new estimator, and variance is reduced by 92%.
Pressure-induced vibrational and superconducting properties of lanthanum hydrides from first principles calculations
Authors: He De-Chun , Shao Han-Xiao , Wei Yong-Kai
Published: August 2015

Pressure-induced vibrational and superconducting properties of lanthanum hydrides (LaH2 and LaH3) have been studied using first principles calculations. It is found that LaH2 and LaH3 are dynamically stable in the pressure ranges of 0–39 GPa and 4–35 GPa, respectively. The character of phonon dispersion curves for LaH2 and LaH3 is analyzed under pressure. The zone-center phonon mode eigen displacements that represent infrared and Raman activity are also obtained, which are essential to the analysis of spectral experiments. The calculations based on Bardeen–Cooper–Schrieffer theory indicate that LaH2 almost has no superconducting behavior even under pressure, in reasonable agreement with previous theoretical calculations and experiments. Whereas, LaH3 presents a considerable high superconducting transition temperature (Tc) at the onset of the face centered cubic structure, while it decreases exponentially under further compression up to 25 GPa and finally almost approaches zero. Further analysis indicates that the underlying mechanism of these two distinct superconducting behaviors are closely related to the hybridization between the HO-s state and La-d state. The mode Grüneisen parameters of two hydrides are also analyzed under 35 GPa, finding that the hydrogen atoms at octahedral sites are responsible for the superconducting properties of LaH3, and in fact, the unobserved superconducting behavior in LaH2 can be interpreted as the absence of hydrogen at octahedral sites compared with LaH3.
Extending invariant complex structures
Authors: Campoamor Stursberg Rutwig , Cardoso Isolda E. , Ovando Gabriela P.
Published: August 2015

We study the problem of extending a complex structure to a given Lie algebra 𝔤, which is firstly defined on an ideal 𝔥 ⊂ 𝔤. We consider the next situations: 𝔥 is either complex or it is totally real. The next question is to equip 𝔤 with an additional structure, such as a (non)-definite metric or a symplectic structure and to ask either 𝔥 is non-degenerate, isotropic, etc. with respect to this structure, by imposing a compatibility assumption. We show that this implies certain constraints on the algebraic structure of 𝔤. Constructive examples illustrating this situation are shown, in particular computations in dimension six are given.
Theoretical investigations of 63Cu2+ orbital Knight shifts for YBa2Cu4O8
Authors: Kuang Min-Quan , Wu Shao-Yi , Zhang Zhi-Hong , Hu Xian-Fen
Published: August 2015

The temperature-independent orbital Knight shifts for the orthorhombic [Formula: see text] site in [Formula: see text] (Y124) are investigated by utilizing the high order perturbation formulae of these parameters for a [Formula: see text] ion situated into orthorhombically elongated octahedra. The calculation results are in good agreement with the experimental data. The moderate quasi-axial anisotropies of the Knight shifts are ascribed to the elongation distortion of the four-fold coordinated Cu[Formula: see text] site. The [Formula: see text] factors are also theoretically calculated in a uniform way for further experimental verification.
Grassmannian Spectral Regression for Learning and Classification
Authors: Azary Sherif , Savakis Andreas
Published: August 2015

Computational performance associated with high dimensional data is a common challenge for real-world action classification systems. Subspace learning, and manifold learning in particular, have received considerable attention as means of finding efficient low-dimensional representations that lead to better classification and efficient processing. A Grassmann manifold is a space that promotes smooth surfaces where points represent subspaces. In this paper, Grassmannian Spectral Regression (GRASP) is presented as a Grassmann inspired subspace learning algorithm that combines the benefits of Grassmann manifolds and spectral regression for fast and accurate classification. GRASP involves embedding high dimensional action subspaces as individual points onto a Grassmann manifold, kernelizing the embeddings onto a projection space, and then applying Spectral Regression for fast and accurate action classification. Furthermore, spatiotemporal action descriptions called Motion History Surfaces and Motion Depth Surfaces are utilized. The effectiveness of GRASP is illustrated for computationally intensive, multi-view and 3D action classification datasets.
Evaluation of Image Forgery Detection Using Multi-Scale Weber Local Descriptors
Authors: Hussain Muhammad , Qasem Sahar , Bebis George , Muhammad Ghulam , Aboalsamh Hatim , Mathkour Hassan
Published: August 2015

Due to the maturing of digital image processing techniques, there are many tools that can forge an image easily without leaving visible traces and lead to the problem of the authentication of digital images. Based on the assumption that forgery alters the texture micro-patterns in a digital image and texture descriptors can be used for modeling this change; we employed two stat-of-the-art local texture descriptors: multi-scale Weber's law descriptor (multi-WLD) and multi-scale local binary pattern (multi-LBP) for splicing and copy-move forgery detection. As the tamper traces are not visible to open eyes, so the chrominance components of an image encode these traces and were used for modeling tamper traces with the texture descriptors. To reduce the dimension of the feature space and get rid of redundant features, we employed locally learning based (LLB) algorithm. For identifying an image as authentic or tampered, Support vector machine (SVM) was used. This paper presents the thorough investigation for the validation of this forgery detection method. The experiments were conducted on three benchmark image data sets, namely, CASIA v1.0, CASIA v2.0, and Columbia color. The experimental results showed that the accuracy rate of multi-WLD based method was 94.19% on CASIA v1.0, 96.52% on CASIA v2.0, and 94.17% on Columbia data set. It is not only significantly better than multi-LBP based method, but also it outperforms other stat-of-the-art similar forgery detection methods.
Nuclear collective excitations: A relativistic density functional approach
Authors: Piekarewicz J.
Published: August 2015

Density functional theory provides the most promising, and likely unique, microscopic framework to describe nuclear systems ranging from finite nuclei to neutron stars. Properly optimized energy density functionals define a new paradigm in nuclear theory where predictive capability is possible and uncertainty quantification is demanded. Moreover, density functional theory offers a consistent approach to the linear response of the nuclear ground state. In this paper, we review the fundamental role played by nuclear collective modes in uncovering novel excitations and in guiding the optimization of the density functional. Indeed, without collective excitations the determination of the density functional remains incomplete. Without collective excitations, the equation of state of neutron-rich matter continues to be poorly constrained. We conclude with a discussion of some of the remaining challenges in this field and propose a path forward to address these challenges.
Collective modes in the superfluid inner crust of neutron stars
Authors: Urban Michael , Oertel Micaela
Published: August 2015

The neutron star inner crust is assumed to be superfluid at relevant temperatures. The contribution of neutron quasiparticles to thermodynamic and transport properties of the crust is therefore strongly suppressed by the pairing gap. Nevertheless, the neutron gas still has low-energy excitations, namely long-wavelength collective modes. We summarize different approaches to describe the collective modes in the crystalline phases of the inner crust and present an improved model for the description of the collective modes in the pasta phases within superfluid hydrodynamics.
The quotient of two Glauberman–Isaacs correspondences
Authors: Turull Alexandre , Wolf Thomas R.
Published: August 2015

Let a finite group [Formula: see text] act coprimely on a finite group [Formula: see text]. The Glauberman–Isaacs correspondence [Formula: see text] is a bijection from the set of [Formula: see text]-invariant irreducible characters of [Formula: see text] onto the set [Formula: see text] of irreducible characters of the centralizer of [Formula: see text] in [Formula: see text]. Let [Formula: see text] be a subgroup of [Formula: see text]. Composing from left to right, it follows that [Formula: see text] is an injection from [Formula: see text] into [Formula: see text]. We show that, in some cases, the map can be defined via the actions of some subgroups of [Formula: see text] containing [Formula: see text] on the centralizers in [Formula: see text] of some other such subgroups. We also show in many instances, such as [Formula: see text] odd or [Formula: see text] supersolvable and [Formula: see text] solvable, that this map is independent of the overgroup [Formula: see text].
A blind digital image watermarking method based on the dyadic wavelet packet transform and fast interval arithmetic techniques
Authors: Ohura Ryuji , Minamoto Teruya
Published: August 2015

We propose a new digital image watermarking method based on the dyadic wavelet packet transform (DYWPT) and fast interval arithmetic (IA) techniques. Because the DYWPT has a redundant representation, like the dyadic wavelet transform (DYWT), the amount of information that the watermark must contain is greater than in the case of methods based on ordinary discrete wavelet transforms (DWTs) and the discrete wavelet packet transform (DWPT). However, the order of the high frequency components is not necessarily the same as the order of their frequency domain. Therefore, in our approach, we rearrange the order of the high frequency components in descending order of frequency components and embed a watermark selectively into higher frequency components. Our watermark is a ternary-valued logo that is embedded into higher frequency components through use of the DYWPT and fast IA techniques. We describe our watermarking procedure in detail and present experimental results demonstrating that our method produces watermarked images that have better quality and are robust with respect to various types of attacks, including marking, clipping, median filtering, contrast tuning (histeq and imadjust commands in the MATLAB Image Processing Toolbox), addition of Gaussian white noise, addition of salt & pepper noise, JPEG and JPEG 2000 compressions, rotation, and resizing.
Effects of Communication Style and Age Diversity in Innovation Teams
Authors: Pesch Robin , Bouncken Ricarda B. , Kraus Sascha
Published: August 2015

This study explores how new product development is affected by age and communication style diversity in teams. Results are derived from a survey study of 232 German SMEs and indicate that a diversity of communication styles in teams has ambivalent effects. On the one hand, it improves a creative team environment that facilitates product innovativeness and speed to market of new product development within teams. On the other hand, it increases relationship conflicts. Even though relationship conflicts have no direct impact on innovation performance, they hamper a creative team environment. Our results indicate that the beneficial effects of communication style diversity outweigh the dysfunctional effects on innovation performance in teams. Age diversity however has only a positive association with relationship conflicts.
Evaluating Science Parks Capacity to Create Competitive Advantages: Comparison of Pardis Technology Park and Sheikh Bahaei Science and Technology Park in Iran
Authors: Sadeghi Mohammad Ebrahim , Sadabadi Ali Asghar
Published: August 2015

Many countries have used science and technology parks to develop high-tech industries. In recent years, Iranian policymakers have been keenly examining this institution. By reviewing papers in this field and considering local dimensions of the issue, we tried to present a framework to evaluate the potential of creating competitive advantages by science and technology parks in Iran. Framework contains “human resources”, “R&D and technology transfer”, “market development” and “facilities” aspects with 12 factors. Use of this evaluation framework will help managers and policymakers of science parks to identify the main requirements of companies and strengths and weaknesses of the parks and the ability to provide more effective services. Finally, by designing the questionnaire and asking the experts (owners and managers of companies located in the Park) the Pardis Technology Park (PTP) and Sheikh Bahaei Science and Technology Park (SBSTP) were evaluated and compared in creating competitive advantages for their firms. The results show that PTP is significantly superior in providing the factors.
On an extension of general coordinate transformations algebra
Authors: Bandelloni Giuseppe
Published: August 2015

An extension of the general coordinate transformations algebra is constructed by means geometrical consistency conditions. A class of infinite invariants is derived. In particular we construct the consistent extension of the gravitational anomaly for each even dimension. The new contributions for these anomalies allow to define an improved Ward operator for which the symmetry is restored.
Arithmetic properties of l-regular overpartitions
Authors: Shen Erin Y. Y.
Published: August 2015

Recently, Andrews introduced the partition function [Formula: see text] as the number of overpartitions of [Formula: see text] in which no part is divisible by [Formula: see text] and only parts [Formula: see text] may be overlined. He proved that [Formula: see text] and [Formula: see text] are divisible by [Formula: see text]. Let [Formula: see text] be the number of overpartitions of [Formula: see text] into parts not divisible by [Formula: see text]. In this paper, we call the overpartitions enumerated by the function [Formula: see text] [Formula: see text]-regular overpartitions. For [Formula: see text] and [Formula: see text], we obtain some explicit results on the generating function dissections. We also derive some congruences for [Formula: see text] modulo [Formula: see text], [Formula: see text] and [Formula: see text] which imply the congruences for [Formula: see text] proved by Andrews. By introducing a rank of vector partitions, we give a combinatorial interpretation of the congruences of Andrews for [Formula: see text] and [Formula: see text].
Solutions of the cubic Fermat equation in ring class fields of imaginary quadratic fields (as periodic points of a 3-adic algebraic function)
Authors: Morton Patrick
Published: August 2015

Explicit solutions of the cubic Fermat equation are constructed in ring class fields [Formula: see text], with conductor [Formula: see text] prime to [Formula: see text], of any imaginary quadratic field [Formula: see text] whose discriminant satisfies [Formula: see text] (mod [Formula: see text]), in terms of the Dedekind [Formula: see text]-function. As [Formula: see text] and [Formula: see text] vary, the set of coordinates of all solutions is shown to be the exact set of periodic points of a single algebraic function and its inverse defined on natural subsets of the maximal unramified, algebraic extension [Formula: see text] of the [Formula: see text]-adic field [Formula: see text]. This is used to give a dynamical proof of a class number relation of Deuring. These solutions are then used to give an unconditional proof of part of Aigner’s conjecture: the cubic Fermat equation has a nontrivial solution in [Formula: see text] if [Formula: see text] (mod [Formula: see text]) and the class number [Formula: see text] is not divisible by [Formula: see text]. If [Formula: see text], congruence conditions for the trace of specific elements of [Formula: see text] are exhibited which imply the existence of a point of infinite order in [Formula: see text].
Affine Refinement Types for Secure Distributed Programming
Authors: Bugliesi Michele , Calzavara Stefano , Eigner Fabienne , Maffei Matteo
Published: August 2015

Recent research has shown that it is possible to leverage general-purpose theorem-proving techniques to develop powerful type systems for the verification of a wide range of security properties on application code. Although successful in many respects, these type systems fall short of capturing resource-conscious properties that are crucial in large classes of modern distributed applications. In this article, we propose the first type system that statically enforces the safety of cryptographic protocol implementations with respect to authorization policies expressed in affine logic. Our type system draws on a novel notion of “exponential serialization” of affine formulas, a general technique to protect affine formulas from the effect of duplication. This technique allows formulate of an expressive logical encoding of the authentication mechanisms underpinning distributed resource-aware authorization policies. We discuss the effectiveness of our approach on two case studies: the EPMO e-commerce protocol and the Kerberos authentication protocol. We finally devise a sound and complete type-checking algorithm, which is the key to achieving an efficient implementation of our analysis technique.
Augmented notes
Authors: Rubart Jessica
Published: August 2015

This article proposes
augmented notes
, which extend paper-based notes with virtual ones on multitouch devices. In the Hypertext community, tools for making notes, structuring and sharing ideas have been worked on in several directions. Augmented notes complement existing approaches by transferring paper-based notes to the virtual world using an interaction metaphor that is well-known from the physical world.
Partitioning of algebraic subexpressions in computer algebra systems
Authors: Fateman Richard
Published: August 2015

A popular technique to direct transformations of algebraic expressions in a computer algebra system such as Macsyma/Maxima or Mathematica is to first write out a pattern or template for some expected class of "input" expressions and use a built-in system routine to match it, identifying pieces and giving them names, then proceeding to compute with these parts. Sometimes this is not such a good approach, and an alternative, presented here, may be more appealing.
Racing line optimization @ race optimal
Authors: Vesel Ricky
Published: August 2015

Race Optimal (www.raceoptimal.com) is a project aimed at creating an effective and fully automated process for racing line optimization in order to produce a database of racing line for racing circuits around the world. The ideal racing line is defined as the trajectory around a track that allows a given vehicle to traverse the circuit in the minimum time. In practice, it is an abstraction that varies with track, environmental conditions, vehicle type and condition, competitive traffic, and other factors. A certain extent of the talent possessed by the elite driver is the ability to perceive this optimal path and its variations, as well as to navigate it as quickly as possible. Until now, automated methods have struggled to match the performance of human-generated or human-guided racing lines [1]. This article describes the optimization engine and representation scheme used at Race Optimal to compute realistic and high performing racing lines for a wide variety of vehicle types.
Evolving multimodal behavior through modular multiobjective neuroevolution
Authors: Schrum Jacob
Published: August 2015

Intelligent organisms do not simply perform one task, but exhibit multiple distinct modes of behavior. For instance, humans can swim, climb, write, solve problems, and play sports. To be fully autonomous and robust, it would be advantageous for artificial agents, both in physical and virtual worlds, to exhibit a similar diversity of behaviors. Artificial evolution, in particular neuroevolution [3, 4], is known to be capable of discovering complex agent behavior. This dissertation expands on existing neuroevolution methods, specifically NEAT (Neuro-Evolution of Augmenting Topologies [7]), to make the discovery of multiple modes of behavior possible. More specifically, it proposes four extensions: (1) multiobjective evolution, (2) sensors that are split up according to context, (3) modular neural network structures, and (4) fitness-based shaping. All of these technical contributions are incorporated into the software framework of Modular Multiobjective NEAT (MM-NEAT), which can be downloaded here.
Optimal buffer-size by synthetic self-similar traces for different traffics for NoC
Authors: Chaurasia Amit , Sehgal Vivek Kumar
Published: August 2015

The importance of the traffic modeling in the field of communication became crucial for the optimization of the network resources used in the communication as the quality of service became the bottleneck in the early design of an architecture. In this paper we analyze different parameters for the quality of service by the multicore architecture using the synthetic generated traces for the multimedia applications. The parameters calculated for the multicore architectures with the help of the synthetic self-similar traces helps the designer to choose the optimal resources in the early design process due to the flexibility nature of the traces which is not possible with the real-time applications. The packet loss probability is calculated for different traffic patterns for different architecture against buffer sizes for different traffic patterns.
Digitally assisted analog front-end power management strategy via dynamic reconfigurability for robust heart rate monitoring
Authors: Zong Chengzhi , Mondal Somok , Hall Drew A. , Jafari Roozbeh
Published: August 2015

This paper presents a reconfiguration methodology to digitally assist a reconfigurable analog front-end (AFE), with the objective of reducing the power consumption of an ECG-based cardiac activity monitoring system, while maintaining an acceptable performance for the desired signal processing. In this study, we focus on the performance of ECG-based heart rate estimation as an example to demonstrate our proposed strategy. Utilizing the consistency and quasi-periodicity of the ECG waveform, two regions are pre-defined based on the prediction of the R peak by a normalized least mean square (NLMS) adaptive filter. The power consumption and performance of the AFE is dynamically reconfigured accordingly. Experimental evaluations show the system can measure heart rate variability (HRV) with an error of 0.5-4 beats/min with the sampling rate reduced from 488 sps to 100 sps and 40 sps for the two regions respectively, bit resolution reduced from 10-bit to 6-bit and noise tolerance substantially relaxed, offering an estimated 62% total power saving.
A Novel Model of Conforming Delaunay Triangulation for Sensor Network Configuration
Authors: Ma Yan , Hao Yan-ling , Tian Feng-min
Published: August 2015

Delaunay refinement is a technique for generating unstructured meshes of triangles for sensor network configuration engineering practice. A new method for solving Delaunay triangulation problem is proposed in this paper, which is called endpoint triangle’s circumcircle model (ETCM). As compared with the original fractional node refinement algorithms, the proposed algorithm can get well refinement stability with least time cost. Simulations are performed under five aspects including refinement stability, the number of additional nodes, time cost, mesh quality after intruding additional nodes, and the aspect ratio improved by single additional node. All experimental results show the advantages of the proposed algorithm as compared with the existing algorithms and confirm the algorithm analysis sufficiently.
Notch1 Activation or Loss Promotes HPV-Induced Oral Tumorigenesis
Authors: Zhong Rong , Bao Riyue , Faber Pieter W. , Bindokas Vytautas P. , Bechill John , Lingen Mark W. , Spiotto Michael T.
Published: August 2015

Viral oncogene expression is insufficient for neoplastic transformation of human cells, so human papillomavirus (HPV)–associated cancers will also rely upon mutations in cellular oncogenes and tumor suppressors. However, it has been difficult so far to distinguish incidental mutations without phenotypic impact from causal mutations that drive the development of HPV-associated cancers. In this study, we addressed this issue by conducting a functional screen for genes that facilitate the formation of HPV E6/E7–induced squamous cell cancers in mice using a transposon-mediated insertional mutagenesis protocol. Overall, we identified 39 candidate driver genes, including Notch1, which unexpectedly was scored by gain- or loss-of-function mutations that were capable of promoting squamous cell carcinogenesis. Autochthonous HPV-positive oral tumors possessing an activated Notch1 allele exhibited high rates of cell proliferation and tumor growth. Conversely, Notch1 loss could accelerate the growth of invasive tumors in a manner associated with increased expression of matrix metalloproteinases and other proinvasive genes. HPV oncogenes clearly cooperated with loss of Notch1, insofar as its haploinsufficiency accelerated tumor growth only in HPV-positive tumors. In clinical specimens of various human cancers, there was a consistent pattern of NOTCH1 expression that correlated with invasive character, in support of our observations in mice. Although Notch1 acts as a tumor suppressor in mouse skin, we found that oncogenes enabling any perturbation in Notch1 expression promoted tumor growth, albeit via distinct pathways. Our findings suggest caution in interpreting the meaning of putative driver gene mutations in cancer, and therefore therapeutic efforts to target them, given the significant contextual differences in which such mutations may arise, including in virus-associated tumors. Cancer Res; 75(18); 3958–69. ©2015 AACR.
Differences in Expression of Key DNA Damage Repair Genes after Epigenetic-Induced BRCAness Dictate Synthetic Lethality with PARP1 Inhibition
Authors: Wiegmans Adrian P. , Yap Pei-Yi , Ward Ambber , Lim Yi Chieh , Khanna Kum Kum
Published: August 2015

The triple-negative breast cancer (TNBC) subtype represents a cancer that is highly aggressive with poor patient outcome. Current preclinical success has been gained through synthetic lethality, targeting genome instability with PARP inhibition in breast cancer cells that harbor silencing of the homologous recombination (HR) pathway. Histone deacetylase inhibitors (HDACi) are a class of drugs that mediate epigenetic changes in expression of HR pathway genes. Here, we compare the activity of the pan-HDAC inhibitor suberoylanilide hydroxamic acid (SAHA), the class I/IIa HDAC inhibitor valproic acid (VPA), and the HDAC1/2–specific inhibitor romidepsin (ROMI) for their capability to regulate DNA damage repair gene expression and in sensitizing TNBC to PARPi. We found that two of the HDACis tested, SAHA and ROMI, but not VPA, indeed inhibit HR repair and that RAD51, BARD1, and FANCD2 represent key proteins whose inhibition is required for HDACi-mediated therapy with PARP inhibition in TNBC. We also observed that restoration of BRCA1 function stabilizes the genome compared with mutant BRCA1 that results in enhanced polyploid population after combination treatment with HDACi and PARPi. Furthermore, we found that overexpression of the key HR protein RAD51 represents a mechanism for this resistance, promoting aberrant repair and the enhanced polyploidy observed. These findings highlight the key components of HR in guiding synthetic lethality with PARP inhibition and support the rationale for utilizing the novel combination of HDACi and PARPi against TNBC in the clinical setting. Mol Cancer Ther; 14(10); 2321–31. ©2015 AACR.
Abstract A09: CD138-negative myeloma cells regulate mechanical properties of bone marrow stromal cells through SDF-1/CXCR4/AKT signaling pathway.
Authors: Wu Dan , Guo Xinyi , Su Jing , Chen Ruoying , Berenzon Dmitriy , Bonin Keith , Guthold Martin , Zhao Weiling , Zhou Xiaobo
Published: August 2015

As the second most prevalent hematologic malignancy, multiple myeloma (MM) remains incurable and relapses due to intrinsic or acquired drug resistance. Therefore, new therapeutic strategies that target molecular mechanisms responsible for drug resistance are attractive. Interactions of tumor cells with their surrounding microenvironment impact tumor initiation, progression and metastasis, as well as patient prognosis. This cross-talk is bidirectional. Tumor cells can also attract or activate tumor-associated stromal cells by releasing cytokines to facilitate their growth, invasion and metastasis. The effect of myeloma cells on bone marrow stromal cells (BMSCs) has not been well studied.

In current study, we determined the effect of myeloma cells on the stiffness of BMSCs and explored the molecular mechanisms underlying these mechanical changes. Cell stiffness measurements were performed using a combined atomic force microscope (AFM)/inverted optical microscope. We found that higher stiffness of BMSCs was not a unique characteristic of BMSCs from MM patients (M-BMSCs). BMSCs from MGUS (Monoclonal gammopathy of undetermined significance) patients were also stiffer than the BMSCs from healthy volunteers (N-BMSCs). The stiffness of M-BMSCs was enhanced when cocultured with myeloma cells. In contrast, no changes were seen in myeloma cell-primed MGUS- and N-BMSCs. Interestingly, our data indicated that CD138- myeloma cells, but not CD138+ cells, regulated M-BMSC stiffness. SDF-1 was highly expressed in the CD138- myeloma subpopulation compared with that in CD138+ cells. Inhibition of SDF-1 using AMD3100 or knocking-down CXCR4 in M-BMSCs blocked CD138- myeloma cells-induced increase in M-BMSC stiffness, suggesting a crucial role of SDF-1/CXCR4. AKT inhibition attenuated SDF-1-induced increases in M-BMSC stiffness. These findings demonstrate, for the first time, CD138- myeloma cell-directed cross-talk with BMSCs and reveal that CD138- myeloma cells regulate M-BMSC stiffness through SDF-1/CXCR4/AKT signaling.

Citation Format: Dan Wu, Xinyi Guo, Jing Su, Ruoying Chen, Dmitriy Berenzon, Keith Bonin, Martin Guthold, Weiling Zhao, Xiaobo Zhou. CD138-negative myeloma cells regulate mechanical properties of bone marrow stromal cells through SDF-1/CXCR4/AKT signaling pathway. [abstract]. In: Proceedings of the AACR Special Conference on Hematologic Malignancies: Translating Discoveries to Novel Therapies; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Clin Cancer Res 2015;21(17 Suppl):Abstract nr A09.
Abstract A38: Remodeling of the malignant bone marrow niche represents a therapeutic target.
Authors: Campbell Timothy B. , Passegué Emmanuelle
Published: August 2015

Myeloproliferative neoplasms (MPNs) are malignant diseases of the hematopoietic stem cell (HSC). Targeting driver mutations in these diseases has had variable success. In chronic myelogenous leukemia (CML), targeting the BCR/ABL pathway has completely changed the way these patients are treated; however, there still remain a significant proportion of patients who have no targetable mutation for therapy and treatments centered on non-cell autonomous pathways of disease progression may have significant value. Previously, our lab showed that malignant myeloid cells from a mouse model of CML overexpressing BCR/ABL (BA mice) expand a remodeled mesenchymal stem cell (MSC) derived osteoblast population which leads to a fibrotic bone marrow (BM) niche and preserves malignant hematopoiesis (Schepers et al. Cell Stem Cell 2013; 13: 285-299). Disrupting the establishment of this fibrotic niche hopefully could delay clinical MPN progression and restore normal hematopoiesis. Bisphosphonates are known to act locally in the BM microenvironment on many cell types and improve the survival of patients with BM-involved disease, including multiple myeloma and breast cancer (Modi and Lentzsch. Leukemia 2012; 26:589-594). The focus of our current studies is to test the effect of zoledronic acid (ZA), a widely used bisphosphonate, on in vitro MSC fibrotic colony formation induced by malignant CML cells. Using whole BM from BA or control mice co-cultured with wild type MSCs, we found that ZA potently inhibited the increase in MSC colony formation induced by CML cells. The significant four-fold increase in MSC colony size (measured by cell number per colony) in BA co-cultures was completely negated by ZA at concentrations as low as 500 nM. The BA co-cultures were exquisitely sensitive to ZA and no breakthrough colonies were seen as compared to a 65 percent reduction in colony size in control co-cultures with 500 nM ZA. Our results suggest that zoledronic acid could be an interesting therapeutic compound to target the fibrotic BM niche in MPNs. Ongoing studies seek to understand the mechanism of action of ZA and to test its efficacy in preventing fibrosis and restoring a healthy BM niche in the BA model of CML. The goal is also to expand these results to other, more strongly fibrotic, mouse models of MPNs and human MPN samples.

Citation Format: Timothy B. Campbell, Emmanuelle Passegué. Remodeling of the malignant bone marrow niche represents a therapeutic target. [abstract]. In: Proceedings of the AACR Special Conference on Hematologic Malignancies: Translating Discoveries to Novel Therapies; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Clin Cancer Res 2015;21(17 Suppl):Abstract nr A38.