bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel Hyperchaotic System and Its Circuit Implementation
Authors: Feng Chaowen , Cai Li , Kang Qiang , Wang Sen , Zhang Hongmei
Published: November 2014

It is very important to generate hyperchaos with more complicated dynamics as a model for theoretical research and practical application. A new hyperchaotic system with double piecewise-linear functions in state equations is presented and physically implemented by circuit design. Based on the theoretical analyses and simulations, the hyperchaotic dynamical properties of this nonlinear system are revealed by equilibria, Lyapunov exponents, and bifurcations, verifying its unusual random nature and indicating its great potential for some relevant engineering applications such as secure communications.
New Deployable Structures Based on an Elastic Origami Model
Authors: Saito Kazuya , Tsukahara Akira , Okabe Yoji
Published: November 2014

Traditionally, origami-based structures are designed on the premise of “rigid folding,” However, every act of folding and unfolding is accompanied by elastic deformations in real structures. This study focuses on these elastic deformations in order to expand origami into a new method of designing morphing structures. The authors start by proposing a simple model for evaluating elastic deformation in nonrigid origami structures. Next, these methods are applied to deployable plate models. Initial strain is introduced into the elastic parts as actuators for deployment. Finally, by using the finite element method (FEM), it is confirmed that the proposed system can accomplish the complete deployment in 3 × 3 Miura-or model.
Performance of Flat-Plate and Compound Parabolic Concentrating Solar Collectors in Underfloor Heating Systems
Authors: Sobhansarbandi Sarvenaz , Atikol Uğur
Published: November 2014

There is a growing interest in using solar energy in underfloor heating systems. However, the large areas required for the installation of solar thermal collector's array can be discouraging, especially in the apartment buildings where the apartment's roof is a common area. The objective of this study is to investigate the possibility of using compound parabolic concentrating (CPC) solar collectors instead of the commonly used flat-plate collectors (FPCs) in such systems. It is aimed to explore the feasibility of area reduction required by the collectors. Second, the temperature profiles of circulating water loop and the concrete slabs are sought to be examined. The system consists of solar thermal collectors, a storage tank, and circulation of water to transport the heat to four similar floor slabs. The CPC collector outlet fluid's temperature can reach a maximum of 95 °C, compared to 70 °C obtained from the FPCs. The results from the simulations show that a 2 m2 CPC collector array can perform satisfactorily to match the job of an 8 m2 FPC array, obtaining the same required circulating water's temperature in the slabs.
A Novel Transformable Structural Mechanism for Doubly Ruled Hypar Surfaces
Authors: Maden Feray , Aktaş Engin , Korkmaz Koray
Published: November 2014

A novel structural mechanism (SM) that is capable of transforming itself into various hyperbolic paraboloid (hypar) geometries is introduced in this paper. Composed of straight bars and novel joint types, the SM is designed based on the ruled surface generation method. Thus, the paper first investigates the geometrical properties and morphology of the hypar surface. Second, it constructs the SM and discusses its transformation capability with respect to its kinematic properties. Then, it presents a parametric model not only to analyze the geometry and possible configurations of the SM but also to prepare a model for the structural analysis. Finally, a transformable shelter structure is proposed as an architectural application of the SM and its feasibility is tested based on the structural analysis conducted in different configurations of the structure. According to the results of the structural analysis, the strength, and the stiffness of the structure are discussed in detail.
Realization of an Inexpensive Embedded Mini-Datalogger for Measuring and Controlling Photovoltaic System
Authors: Houcine Naim , Abdelatif Hassini , Noureddine Benabadji , Fatima Zohra Falil , Abed Bouadi
Published: November 2014

This article describes the design and the realization of an automatic recording device for measurements and controls of multiple physical parameters, in order to manage and monitor a mini central photovoltaic (PV) electricity. It is based on an 8-bit microcontroller, a PIC16F716, which is the lowest cost in the midrange portfolio from Microchip. The automatic recording device (or datalogger) measures the following parameters: the current sourced by a set of PV panels to solar batteries, the voltage across these batteries, the internal and the external temperatures, through a 4 channel multiplexed 8-bit analog–digital converter (ADC) integrated module. This datalogger is clocked with a real time clock and calendar (RTCC), which controls also the periodic measurements. These are stored in an external 8 kB flash electrically erasable/programable read-only memory (EEPROM), a 24LC64, using the I2C protocol, which allows us to easily increase the storage capacity by adding, if necessary, in parallel, up to eight external flash EEPROM.
Metal artifact correction for x‐ray computed tomography using kV and selective MV imaging
Authors: Wu Meng , Keil Andreas , Constantin Dragos , Star‐Lack Josh , Zhu Lei , Fahrig Rebecca
Published: November 2014

Purpose:

The overall goal of this work is to improve the computed tomography (CT) image quality for patients with metal implants or fillings by completing the missing kilovoltage (kV) projection data with selectively acquired megavoltage (MV) data that do not suffer from photon starvation. When both of these imaging systems, which are available on current radiotherapy devices, are used, metal streak artifacts are avoided, and the soft‐tissue contrast is restored, even for regions in which the kV data cannot contribute any information.

Methods:

Three image‐reconstruction methods, including two filtered back‐projection (FBP)‐based analytic methods and one iterative method, for combining kV and MV projection data from the two on‐board imaging systems of a radiotherapy device are presented in this work. The analytic reconstruction methods modify the MV data based on the information in the projection or image domains and then patch the data onto the kV projections for a FBP reconstruction. In the iterative reconstruction, the authors used dual‐energy (DE) penalized weighted least‐squares (PWLS) methods to simultaneously combine the kV/MV data and perform the reconstruction.

Results:

The authors compared kV/MV reconstructions to kV‐only reconstructions using a dental phantom with fillings and a hip‐implant numerical phantom. Simulation results indicated that dual‐energy sinogram patch FBP and the modified dual‐energy PWLS method can successfully suppress metal streak artifacts and restore information lost due to photon starvation in the kV projections. The root‐mean‐square errors of soft‐tissue patterns obtained using combined kV/MV data are 10–15 Hounsfield units smaller than those of the kV‐only images, and the structural similarity index measure also indicates a 5%–10% improvement in the image quality. The added dose from the MV scan is much less than the dose from the kV scan if a high efficiency MV detector is assumed.

Conclusions:

The authors have shown that it is possible to improve the image quality of kV CTs for patients with metal implants or fillings by completing the missing kV projection data with selectively acquired MV data that do not suffer from photon starvation. Numerical simulations demonstrated that dual‐energy sinogram patch FBP and a modified kV/MV PWLS method can successfully suppress metal streak artifacts and restore information lost due to photon starvation in kV projections. Combined kV/MV images may permit the improved delineation of structures of interest in CT images for patients with metal implants or fillings.
Mad1 for Integrin Trafficking
Authors: VanHook Annalisa M.
Published: November 2014

Mad1 promotes trafficking of the α5 integrin subunit to the plasma membrane during interphase.
HIV Drugs Can Dampen Inflammation, Too
Authors: Mueller Kristin L.
Published: November 2014

Anti-HIV nucleoside analogs treat retinal degeneration and graft-versus-host disease in mice.
The Gut Microbiota and the Blood-Brain Barrier
Authors: Smith Orla
Published: November 2014

The intestinal microbiota contribute to the integrity of the blood-brain barrier in fetal and adult mice.
Crowdsourcing Disease Prognosis
Authors: Tsalik Ephraim L.
Published: November 2014

Opening clinical trial data to crowdsourcing improves prognosis in ALS.
Role of the FtsA C Terminus as a Switch for Polymerization and Membrane Association
Authors: Krupka Marcin , Cabré Elisa J. , Jiménez Mercedes , Rivas Germán , Rico Ana Isabel , Vicente Miguel
Published: November 2014

Together with ATP, the C-terminal region of the essential streptococcal FtsA protein acts as an intramolecular switch to promote its polymerization and attachment to the membrane. During septation, FtsA is known to anchor the constricting FtsZ ring and, subsequently, the divisome to the membrane. Truncation of the C terminus of the streptococcal FtsA (FtsAΔCt) facilitates a more rapid ATP-dependent polymerization in solution than is seen with the full-length protein (FtsA
+
). The FtsAΔCt polymers are more organized and compact than those formed in solution by FtsA
+
, resembling the shape of the membrane-associated FtsA
+
polymers. We find that ATP, besides being needed for polymerization, is required for the attachment of FtsA
+
to lipid monolayers and to vesicle membranes. We propose a model in which the binding of ATP activates a switch favoring the polymerization of FtsA and at the same time driving the amphipathic helix at its C terminus to become attached to the membrane. Conversely, when FtsA is in the cytoplasm, the C terminus is not engaged in the attachment to the membrane, and it obstructs polymerization. ATP-dependent polymerization of FtsA inside membrane vesicles causes vesicle shrinkage, suggesting that, besides providing a membrane attachment for FtsZ, the FtsA C terminus may also introduce local alterations in the membrane to facilitate septation.

IMPORTANCE
FtsA is a protein needed in many bacteria to construct a septum that divides one fully grown cell, producing two daughters. We show that the region located at the C-terminal end of the
Streptococcus pneumoniae
FtsA protein works as a switch triggered by ATP, a molecule that stores energy. This region contains an amphipathic helix that obstructs the assembly of FtsA into polymers in the cytoplasm. In the presence of ATP, the obstruction is removed by switching the position of the helix. The switch directs the helix to the membrane and simultaneously facilitates the polymerization of the protein. The accumulation of FtsA molecules at the membrane causes distortions, an effect produced also by proteins such as MinD, MreB, and SepF that also contain amphipathic helixes as membrane attachment devices. In the case of FtsA, these distortions may also facilitate the initial events that lead to the division of bacteria.
Internal Sense of Direction: Sensing and Signaling from Cytoplasmic Chemoreceptors
Authors: Collins Kieran D. , Lacal Jesus , Ottemann Karen M.
Published: November 2014

Chemoreceptors sense environmental signals and drive chemotactic responses in
Bacteria
and
Archaea
. There are two main classes of chemoreceptors: integral inner membrane and soluble cytoplasmic proteins. The latter were identified more recently than integral membrane chemoreceptors and have been studied much less thoroughly. These cytoplasmic chemoreceptors are the subject of this review. Our analysis determined that 14% of bacterial and 43% of archaeal chemoreceptors are cytoplasmic, based on currently sequenced genomes. Cytoplasmic chemoreceptors appear to share the same key structural features as integral membrane chemoreceptors, including the formations of homodimers, trimers of dimers, and 12-nm hexagonal arrays within the cell. Cytoplasmic chemoreceptors exhibit varied subcellular locations, with some localizing to the poles and others appearing both cytoplasmic and polar. Some cytoplasmic chemoreceptors adopt more exotic locations, including the formations of exclusively internal clusters or moving dynamic clusters that coalesce at points of contact with other cells. Cytoplasmic chemoreceptors presumably sense signals within the cytoplasm and bear diverse signal input domains that are mostly N terminal to the domain that defines chemoreceptors, the so-called MA domain. Similar to the case for transmembrane receptors, our analysis suggests that the most common signal input domain is the PAS (Per-Arnt-Sim) domain, but a variety of other N-terminal domains exist. It is also common, however, for cytoplasmic chemoreceptors to have C-terminal domains that may function for signal input. The most common of these is the recently identified chemoreceptor zinc binding (CZB) domain, found in 8% of all cytoplasmic chemoreceptors. The widespread nature and diverse signal input domains suggest that these chemoreceptors can monitor a variety of cytoplasmically based signals, most of which remain to be determined.
Hypercementosis: a rare finding in a patient with systemic lupus erythematosus
Authors: Shoor Hitesh , Sujir Nanditha , Mutalik Sunil , Pai Keerthilatha M
Published: November 2014

Hypercementosis is excessive deposition of non-neoplastic cementum over normal root cementum, which alters root morphology. This cementum may be either hypocellular or cellular in nature. The aetiopathogenesis of hypercementosis is ambiguous. Although most of the cases are idiopathic, several local and systemic factors are also linked to this condition, such as Paget's disease, acromegaly, vitamin A deficiency, etc. We report two rare cases of hypercementosis associated with systemic lupus erythematosus, not previously described in the literature, and also discuss the possible aetiopathogenesis.
Suicide Information Database-Cymru: a protocol for a population-based, routinely collected data linkage study to explore risks and patterns of healthcare contact prior to suicide to identify opportunities for intervention
Authors: John Ann , Dennis M , Kosnes L , Gunnell D , Scourfield J , Ford D V , Lloyd K
Published: November 2014

Introduction

Prevention of suicide is a global public health challenge extending beyond mental health services. Linking routinely collected health and social care system data records for the same individual across different services and over time has enormous potential in suicide research. Most previous research linking suicide mortality data with routinely collected electronic health records involves only one or two domains of healthcare provision such as psychiatric inpatient care. This protocol paper describes the development of a population-based, routinely collected data linkage study: the Suicide Information Database Cymru (SID-Cymru). SID-Cymru aims to contribute to the information available on people who complete suicide.

Methods and analysis

SID-Cymru will facilitate a series of electronic case–control studies based in the Secure Anonymised Information Linkage (SAIL) Databank. We have identified 2664 cases of suicide in Wales between 2003 and 2011 from routinely collected mortality data using International Classification of Diseases, Tenth Revision, codes X60–X84 (intentional self-harm) and Y10–Y34 (undetermined intent). Each case will be matched by age and sex to at least five controls. Records will be collated and linked from routinely collected health and social data in Wales for each individual. Conditional logistic regression will be applied to produce crude and confounder (including general practice, socioeconomic status) adjusted ORs.

Ethics and dissemination

The SAIL Databank has the required ethical permissions in place to analyse anonymised data. Ethical approval has been granted by the Information Governance Review Panel (IGRP). Findings will be disseminated through peer-reviewed publications, consultations with stakeholders and national/international conference presentations. The improved understanding of the prior health, nature of previous contacts with services and wider social circumstances of those who complete suicide will assist in prevention policy, service organisation and delivery. SID-Cymru is funded through the National Institute for Social Care and Health Research, Welsh Government (RFS-12-25).
Clinicopathological correlates of adrenal Cushing's syndrome
Authors: Duan Kai , Hernandez Karen Gomez , Mete Ozgur
Published: November 2014

Endogenous Cushing's syndrome is a rare endocrine disorder that incurs significant cardiovascular morbidity and mortality, due to glucocorticoid excess. It comprises adrenal (20%) and non-adrenal (80%) aetiologies. While the majority of cases are attributed to pituitary or ectopic corticotropin (ACTH) overproduction, primary cortisol-producing adrenal cortical lesions are increasingly recognised in the pathophysiology of Cushing's syndrome. Our understanding of this disease has progressed substantially over the past decade. Recently, important mechanisms underlying the pathogenesis of adrenal hypercortisolism have been elucidated with the discovery of mutations in cyclic AMP signalling (PRKACA, PRKAR1A, GNAS, PDE11A, PDE8B), armadillo repeat containing 5 gene (ARMC5) a putative tumour suppressor gene, aberrant G-protein-coupled receptors, and intra-adrenal secretion of ACTH. Accurate subtyping of Cushing's syndrome is crucial for treatment decision-making and requires a complete integration of clinical, biochemical, imaging and pathology findings. Pathological correlates in the adrenal glands include hyperplasia, adenoma and carcinoma. While the most common presentation is diffuse adrenocortical hyperplasia secondary to excess ACTH production, this entity is usually treated with pituitary or ectopic tumour resection. Therefore, when confronted with adrenalectomy specimens in the setting of Cushing's syndrome, surgical pathologists are most commonly exposed to adrenocortical adenomas, carcinomas and primary macronodular or micronodular hyperplasia. This review provides an update on the rapidly evolving knowledge of adrenal Cushing's syndrome and discusses the clinicopathological correlations of this important disease.
Changes in migratory fish communities and their health, hydrology, and water chemistry in rivers of the Athabasca oil sands region: a review of historical and current data
Authors: Schwalb Astrid N. , Alexander Alexa C. , Paul Andrew J. , Cottenie Karl , Rasmussen Joseph B.
Published: November 2014

The long-lived migratory fish in the lower Athabasca region (including the Athabasca oil sands region) are valued ecosystem components and good bio-indicators of changes in habitat condition, water quality and quantity over the entire stream network. Changes in this region may have been caused by a variety of human activities including oil sands development, forestry, urban development, and recreational activities. We reviewed existing data to examine whether community composition and health of migratory fish (such as northern pike, walleye, and suckers) in the lower Athabasca region have changed over the past 40 years and whether these could be explained by changes in hydrology or water chemistry. Declines of 53%–100% in the abundance of three migratory fish species were detected in the Muskeg watershed (15% land change). Significant changes in fish health were detected. The largest decreases in body condition of fish in the region occurred in the late 1990s and coincided with elevated levels of fin erosion, the most frequently occurring external abnormality, and with extreme discharge conditions. Fish habitat can be affected by both increases and decreases in discharge, and the most pronounced changes were increases in some watersheds of up to 20% of average discharge post-development. In contrast, decreases in discharge post-development in the Muskeg and Steepbank rivers correlated with a decrease in precipitation. Our results show that climatic events and landscape features such as wetlands are important for understanding changes in the system. Further research is needed to examine potential ecological consequences of the observed changes in hydrology for fish and to explore what caused the changes in migratory fish communities and fish health. This will require a better understanding of the trophic structure of the system and a better monitoring program for migratory fish.
Operational issues and assessment of risk for light UAVs
Authors: Guglieri G. , Quagliotti F. , Ristorto G.
Published: November 2014

ENAC, the Italian Civil Aviation Authority, has published the regulation for remotely piloted aircraft systems (RPAS) with a maximum take-off mass of less than 150 kg. The aim of this paper is the application of Italian regulatory prescriptions for risk assessment to a family of RPAS. The results of this analysis, performed in collaboration with ENAC, are compared with other available methods, providing a comprehensive insight for mission feasibility and operational implications in a set of realistic application cases. Practical solutions are proposed for risk mitigation of RPAS specialized operations.
Homogenization of a multiscale viscoelastic model with nonlocal damping, application to the human lungs
Authors: Cazeaux Paul , Grandmont Céline
Published: November 2014

We are interested in the mathematical modeling of the deformation of the human lung tissue, called the lung parenchyma, during the respiration process. The parenchyma is a foam-like elastic material containing millions of air-filled alveoli connected by a tree-shaped network of airways. In this study, the parenchyma is governed by the linearized elasticity equations and the air movement in the tree by the Poiseuille law in each airway. The geometric arrangement of the alveoli is assumed to be periodic with a small period ε > 0. We use the two-scale convergence theory to study the asymptotic behavior as ε goes to zero. The effect of the network of airways is described by a nonlocal operator and we propose a simple geometrical setting for which we show that this operator converges as ε goes to zero. We identify in the limit the equations modeling the homogenized behavior under an abstract convergence condition on this nonlocal operator. We derive some mechanical properties of the limit material by studying the homogenized equations: the limit model is nonlocal both in space and time if the parenchyma material is considered compressible, but only in space if it is incompressible. Finally, we propose a numerical method to solve the homogenized equations and we study numerically a few properties of the homogenized parenchyma model.
Carbon Dioxide Adsorption Behavior of Modified HKUST-1
Authors: Ma Lan , Tang Huamin , Zhou Chaohua , Zhang Hongpeng , Yan Chunxiao , Hu Xiaochun , Yang Yang , Yang Weiwei , Li Yuming , He Dehua
Published: November 2014

A kind of typical metal-organic frameworks (MOFs) material, HKUST-1 was prepared by hydrothermal method and characterized by XRD and SEM. The results of characterizations manifested that HKUST-1 showed a regular octahedral crystal structure. The as-prepared HKUST-1 was modified by several kinds of organic base materials and the CO 2 adsorption behaviors of modified HKUST-1 materials were evaluated. The CO 2 adsorption capacities of different base modified HKUST-1 varied with the base intensity of modified organic base materials.
Soluble meso-tetrakis(arylethynyl)porphyrins — synthesis and optical properties
Authors: Nowak-Król Agnieszka , Łukasiewicz Łukasz G. , Haley Joy E. , Drobizhev Mikhail , Rebane Aleksander , Cooper Thomas M. , Gryko Daniel T.
Published: November 2014

Trans- A 2 B 2-tetrakis(arylethynyl)porphyrins with suitable solubility in CH 2 Cl 2, CHCl 3, EtOAc , acetone and toluene have been obtained for the first time. Among two possible strategies the one comprising the synthesis of 5,15-dibromo-10,20-bis[(isopropylsilyl)ethynyl]porphyrin proved to be more efficient. The pathway towards densely substituted arylacetylenes has been optimized. The use of previously identified 3,4,5-trialkoxyaryl substituent was crucial for achieving the reasonable solubility. The optical properties of meso-substituted tetrakis(arylethynyl)porphyrins were studied showing that strong polarization imparted by direct conjugation of all four substituents with porphyrin core resulted not only in strong absorption of red light but also in a relatively long triplet lifetime. Meso-tetrakis(arylethynyl)porphyrins have a significantly longer lifetime of T1 state than bis(arylethynyl)porphyrins and in their case all the states are mixtures of transitions between the HOMO-1, HOMO and LUMO, LUMO+1 MOs. We show that the presence of two additional arylethynyl substituents at meso-positions enhance the maximum two-photon absorption cross-section of trans- A 2 B 2-tetrakis(arylethynyl)porphyrins by more than one order of magnitude. Maximum values as high as σ2 = 500 GM at 950 nm result from realization of suitable conditions for effective resonance enhancement along with a lowering of the energy and intensification of the two-photon allowed transitions in the Soret region.
A fast auto-focusing method of microscopic imaging based on an improved MCS algorithm
Authors: Fu Guangkai , Cao Yiping , Lu Mingteng
Published: November 2014

An improved "three steps" mountain-climb searching (MCS) algorithm is proposed which is applied to auto-focusing for microscopic imaging accurately and efficiently. By analyzing the performance of several evaluation functions, the variance function and the Brenner function are synthesized as a new evaluation function. In the first step, a self-adaptive step length which is much dependent on the reciprocal of the evaluation function value at the beginning position of climbing is used for approaching the halfway up the mountain roughly. Secondly, a fixed moderate step length is applied for approaching the mountaintop of the variance function as closer as possible. Finally, a fine step is employed for reaching the exact mountaintop of the Brenner function. The microscope auto-focusing experiments based on the proposed algorithm for blood smear detection have been carried out comprehensively. The results show that the improved algorithm can not only guarantee the precision to get clear focal images, but also improve the auto-focusing efficiency.
Optimizing signal collection efficiency of the VIPA-based Brillouin spectrometer
Authors: Meng Zhaokai , Yakovlev Vladislav V.
Published: November 2014

Brillouin spectroscopy is an emerging tool for microscopic optical imaging as it allows for noninvasive and direct assessment of the viscoelastic properties of materials. Recent advances of background-free confocal Brillouin spectrometer allows investigators to acquire the Brillouin spectra for turbid samples as well as transparent ones. However, due to strong signal loss induced by the imperfect optical setup, the Brillouin photons are usually immersed in background noise. In this report, we proposed and experimentally demonstrated multiple approaches to enhance the signal collection efficiency. A signal enhancement by > 4 times can be observed, enabling observation of ultra-weak signals.
Molecular Beacon Enables Combination of Highly Processive and Highly Sensitive Rolling Circle Amplification Readouts for Detection of DNA-Modifying Enzymes
Authors: Kristoffersen Emil L. , Gonzalez Maria , Stougaard Magnus , Tesauro Cinzia
Published: November 2014

Here we present an optimized readout format for detection of the circularized products from a DNA-based sensor for measurement of DNA-modifying enzymes including DNA Topoisomerase I. The basic design of the DNA-sensor relies on the use of a substrate that can be circularized by the activity of DNA-modifying enzymes like type IB Topoisomerases and subsequently amplified by a rolling circle amplification (RCA) mechanism. The RCA process can be followed in real-time by the addition of a molecular beacon with a fluorophore/quencher pair. Upon hybridization to the amplified product, the fluorophore/quencher pair is separated, giving rise to a fluorescent signal, measurable in pseudo real-time using a qPCR machine or in a fluorimeter. The RCA products in complex with the molecular beacon can subsequently be moved to microscopic slides and analyzed in a fluorescence microscope. We describe the proof of the principle of this molecular beacon-based method combining the qPCR readout format with the standard Rolling circle Enhanced Enzymatic Assay previously reported. Although the qPCR setup is less sensitive, it allows easy, fast, and high-throughput measurement of enzyme activities. Human Topoisomerase IB (TopIB) is a well-known target for the clinically used anticancer drugs of the camptothecin family. The cytotoxic effect of camptothecins correlates directly with the intracellular TopIB activity affecting reversibly the Topoisomerase/DNA cleavage complexes. Therefore, we envisioned that the presented method may find use for the prediction of cellular drug response and for drug screening to discover novel molecules that specifically inhibit TopIB or other DNA-modifying enzymes.
Editor's introduction
Authors: Procaccia Ariel D.
Published: November 2014

Issue 12.2 of SIGecom Exchanges includes a letter from David Parkes in his role as the SIG chair, a position paper, and six research letters. By now this new format should be familiar from issues 11.2 and 12.1, with the caveat that the SIG-related letter alternates between the SIG chair and the PC chairs of EC (which, as David explains in his letter, is now the
ACM Conference on Economics and Computation
).
Arbitration and stability in cooperative games
Authors: Zick Yair , Elkind Edith
Published: November 2014

We present a formal framework for handling deviation in settings where players divide resources among multiple projects, forming overlapping coalition structures. Having formed such a coalition structure, players share the revenue generated among themselves. Given a profit division, some players may decide that they are underpaid, and deviate from the outcome. The main insight of the work presented in this survey is that when players want to deviate, they must know how the non-deviators would react to their deviation: after the deviation, the deviators may still work with some of the non-deviators, which presents an opportunity for the non-deviators to exert leverage on deviators. We extend the
overlapping coalition formation (OCF)
model of Chalkiadakis et al. [2010] for cooperation with partial coalitions, by introducing
arbitration functions
, a general framework for handling deviation in OCF games. We review some interesting aspects of the model, characterizations of stability in this model, as well as methods for computing stable outcomes.
Strategyproof facility location with concave costs
Authors: Fotakis Dimitris , Tzamos Christos
Published: November 2014

In
k
-Facility Location games,
n
strategic agents report their locations on the real line and a mechanism maps them to
k
facilities. Each agent seeks to minimize her connection cost to the nearest facility and the mechanism should be strategyproof and approximately efficient. Facility Location games have received considerable attention in the framework of approximate mechanism design without money. In this letter, we discuss some recent positive results on the approximability of
k
-Facility Location by randomized strategyproof mechanisms. Interestingly, these results hold even if the agents' connection cost is a concave cost function of the distance.
Structure and learning of valuation functions
Authors: Feldman Vitaly , Vondrák Jan
Published: November 2014

We discuss structural results and learning algorithms for submodular and fractionally subadditive valuation functions. While learning these valuation functions over general distributions turns out to be hard, we present compact approximate representations and efficient learning algorithms for such functions over the uniform distribution.
Bayesian algorithmic mechanism design
Authors: Chawla Shuchi , Sivan Balasubramanian
Published: November 2014

This article surveys recent work with an algorithmic flavor in Bayesian mechanism design. Bayesian mechanism design involves optimization in economic settings where the designer possesses some stochastic information about the input. Recent years have witnessed huge advances in our knowledge and understanding of algorithmic techniques for Bayesian mechanism design problems. These include, for example, revenue maximization in settings where buyers have multi-dimensional preferences, optimization of non-linear objectives such as makespan, and generic reductions from mechanism design to algorithm design. However, a number of tantalizing questions remain un-solved.

This article is meant to serve as an introduction to Bayesian mechanism design for a novice, as well as a starting point for a broader literature search for an experienced researcher.
The economics of the cloud
Authors: Anselmi Jonatha , Ardagna Danilo , Lui John C. S. , Wierman Adam , Xu Yunjian , Yang Zichao
Published: November 2014

This letter provides an overview of our recent work studying the impacts of price competition and congestion in the cloud marketplace. Specifically, we discuss a three-tier market model that studies a vertical marketplace where users purchase services from Software-as-a-Service (SaaS) providers, which in turn purchase computing resources from either Provider-as-a-Service (PaaS) or Infrastructure-as-a-Service (IaaS) providers.
The output-agreement method induces honest behavior in the presence of social projection
Authors: Carvalho Arthur , Dimitrov Stanko , Larson Kate
Published: November 2014

The output-agreement method has been successfully used to reward agents in a variety of crowdsourcing settings. This method consists of a simple payment function that randomly matches two agents' reported information and rewards agreement. In this letter, we discuss how the output-agreement method might induce honest behavior when there exists
social projection, i.e
., when each agent believes that his private information is the most popular one amongst his peers.
Dynamic power management for thermal control of many-core real-time systems
Authors: Becker Matthias , Sandström Kristian , Behnam Moris , Nolte Thomas
Published: November 2014

Many-core systems, processors incorporating numerous cores interconnected by a Network on Chip (NoC), provide the computing power needed by future applications. High power density caused by the steadily shrinking transistor size, which is still following Moore's law, leads to a number of problems such as overheating cores, affecting processor reliability and lifetime. Embedded real-time systems are exposed to a changing ambient temperature and thus need to adapt their configuration in order to keep the individual core temperature below critical values. In our approach a hysteresis controller is implemented on each core, triggering a redistribution of the cores' workload and the transition into an idle state allowing the core to cool down. We propose two approaches, one global and one local approach, to redistribute the tasks and relive overheating cores during runtime. We evaluate the two proposed approaches by comparing them against each other based on simulations.
Rorα deficiency and decreased adiposity are associated with induction of thermogenic gene expression in subcutaneous white adipose and brown adipose tissue
Authors: Lau Patrick , Tuong Zewen K. , Wang Shu-Ching , Fitzsimmons Rebecca L. , Goode Joel M. , Thomas Gethin P. , Cowin Gary J. , Pearen Michael A. , Mardon Karine , Stow Jennifer L. , Muscat George E. O.
Published: November 2014

The Rar-related orphan receptor-α (Rorα) is a nuclear receptor that regulates adiposity and is a potential regulator of energy homeostasis. We have demonstrated that the Rorα-deficient staggerer ( sg/sg) mice display a lean and obesity-resistant phenotype. Adaptive Ucp1-dependent thermogenesis in beige/brite and brown adipose tissue serves as a mechanism to increase energy expenditure and resist obesity. DEXA and MRI analysis demonstrated significantly decreased total fat mass and fat/lean mass tissue ratio in male chow-fed sg/sg mice relative to wt mice. In addition, we observed increased Ucp1 expression in brown adipose and subcutaneous white adipose tissue but not in visceral adipose tissue from Rorα-deficient mice. Moreover, this was associated with significant increases in the expression of the mRNAs encoding the thermogenic genes (i.e., markers of brown and beige adipose) Pparα, Errα, Dio2, Acot11/Bfit, Cpt1β, and Cidea in the subcutaneous adipose in the sg/sg relative to WT mice. These changes in thermogenic gene expression involved the significantly increased expression of the (cell-fate controlling) histone-lysine N-methyltransferase 1 (Ehmt1), which stabilizes the Prdm16 transcriptional complex. Moreover, primary brown adipocytes from sg/sg mice displayed a higher metabolic rate, and further analysis was consistent with increased uncoupling. Finally, core body temperature analysis and infrared thermography demonstrated that the sg/sg mice maintained greater thermal control and cold tolerance relative to the WT littermates. We suggest that enhanced Ucp1 and thermogenic gene expression/activity may be an important contributor to the lean, obesity-resistant phenotype in Rorα-deficient mice.
Optimizing the Long-Term Operating Plan of Railway Marshalling Station for Capacity Utilization Analysis
Authors: Zhou Wenliang , Yang Xia , Qin Jin , Deng Lianbo
Published: November 2014

Not only is the operating plan the basis of organizing marshalling station’s operation, but it is also used to analyze in detail the capacity utilization of each facility in marshalling station. In this paper, a long-term operating plan is optimized mainly for capacity utilization analysis. Firstly, a model is developed to minimize railcars’ average staying time with the constraints of minimum time intervals, marshalling track capacity, and so forth. Secondly, an algorithm is designed to solve this model based on genetic algorithm (GA) and simulation method. It divides the plan of whole planning horizon into many subplans, and optimizes them with GA one by one in order to obtain a satisfactory plan with less computing time. Finally, some numeric examples are constructed to analyze (1) the convergence of the algorithm, (2) the effect of some algorithm parameters, and (3) the influence of arrival train flow on the algorithm.
Coverage Capacity Optimization for Mobile Sensor Networks Based on Evolutionary Games
Authors: Liu Jianhua , Yue Guangxue , Shen Shigen , Shang Huiliang , Li Hongjie
Published: November 2014

The optimal and distributed provisioning of high coverage capacity in mobile sensor networks is known as a fundamental but hard problem. The situation is exacerbated in a mobile wireless setting due to the dynamic coverage of a mobile sensor network resulting from continuous movement of sensors. In this paper, we propose an optimization framework for maximizing the coverage capacity in mobile sensor networks that comprise both stationary sensors (SSs) and mobile sensors (MSs). Both the intracoverage capacity and the intercoverage capacity are jointly optimized by considering the control of the power and distance between MSs and SSs and the interference among MSs. We propose a new noncooperative control algorithm that iteratively solves intracoverage capacity optimization between MSs and SSs. We also further formulate intercoverage capacity as evolutionary coalition game and present a new cooperative interference control algorithm that iteratively solves intercoverage capacity optimization among MSs. We prove the existence of a solution for iteration control equation of the power and distance and the interference to maximize the coverage capacity. Finally, we assess the performance of the proposed algorithm and show that proposed control scheme can effectively improve the average coveragecapacity in mobile sensor networks.
Antioxidant Capacity and Radical Scavenging Effect of Polyphenol RichMallotus philippenensisFruit Extract on Human Erythrocytes: AnIn VitroStudy
Authors: Gangwar Mayank , Gautam Manish Kumar , Sharma Amit Kumar , Tripathi Yamini B. , Goel R. K. , Nath Gopal
Published: November 2014

Mallotus philippinensisis an important source of molecules with strong antioxidant activity widely used medicinal plant. Previous studies have highlighted their anticestodal, antibacterial, wound healing activities, and so forth. So, present investigation was designed to evaluate the total antioxidant activity and radical scavenging effect of 50% ethanol fruit glandular hair extract (MPE) and its role on Human Erythrocytes. MPE was tested for phytochemical test followed by its HPLC analysis. Standard antioxidant assays like DPPH, ABTS, hydroxyl, superoxide radical, nitric oxide, and lipid peroxidation assay were determined along with total phenolic and flavonoids content. Results showed that MPE contains the presence of various phytochemicals, with high total phenolic and flavonoid content. HPLC analysis showed the presence of rottlerin, a polyphenolic compound in a very rich quantity. MPE exhibits significant strong scavenging activity on DPPH and ABTS assay. Reducing power showed dose dependent increase in concentration absorption compared to standard, Quercetin. Superoxide, hydroxyl radical, lipid peroxidation, nitric oxide assay showed a comparable scavenging activity compared to its standard. Our finding further provides evidence thatMallotusfruit extract is a potential natural source of antioxidants which have a protective role on human Erythrocytes exhibiting minimum hemolytic activity and this justified its uses in folklore medicines.
Identification and Antimicrobial Resistance ofEnterococcusSpp. Isolated from the River and Coastal Waters in Northern Iran
Authors: Alipour Majid , Hajiesmaili Reza , Talebjannat Maryam , Yahyapour Yousef
Published: November 2014

As fecal streptococci commonly inhabit the intestinal tract of humans and warm blooded animals, and daily detection of all pathogenic bacteria in coastal water is not practical, thus these bacteria are used to detect the fecal contamination of water. The present study examined the presence and the antibiotic resistance patterns ofEnterococcusspp. isolated from the Babolrud River in Babol and coastal waters in Babolsar. Seventy samples of water were collected in various regions of the Babolrud and coastal waters. Isolated bacteria were identified to the species level using standard biochemical tests and PCR technique. In total, 70Enterococcusspp. were isolated from the Babolrud River and coastal waters of Babolsar.Enterococcus faecalis(68.6%) andEnterococcus faecium(20%) were the most prevalent species. Resistance to chloramphenicol, ciprofloxacin, and tetracyclin was prevalent. The presence of resistantEnterococcusspp. in coastal waters may transmit resistant genes to other bacteria; therefore, swimming in such environments is not suitable.
Gastroretentive Pulsatile Release Tablets of Lercanidipine HCl: Development, Statistical Optimization, andIn VitroandIn VivoEvaluation
Authors: Reddy Gagganapalli Santhoshi , Nayak Usha Yogendra , Deshpande Praful Balavant , Mutalik Srinivas
Published: November 2014

The present study was aimed at the development of gastroretentive floating pulsatile release tablets (FPRTs) of lercanidipine HCl to enhance the bioavailability and treat early morning surge in blood pressure. Immediate release core tablets containing lercanidipine HCl were prepared and optimized core tablets were compression-coated using buoyant layer containing polyethylene oxide (PEO) WSR coagulant, sodium bicarbonate, and directly compressible lactose. FPRTs were evaluated for variousin vitrophysicochemical parameters, drug-excipient compatibility, buoyancy, swelling, and release studies. The optimized FPRTs were testedin vivoin New Zealand white rabbits for buoyancy and pharmacokinetics. DoE optimization of data revealed FPRTs containing PEO (20% w/w) with coat weight 480 mg were promising systems exhibiting good floating behavior and lag time in drug release. Abdominal X-ray imaging of rabbits after oral administration of the tablets, confirmed the floating behavior and lag time. A quadratic model was suggested for release at 7th and 12th h and a linear model was suggested for release lag time. The FPRT formulation improved pharmacokinetic parameters compared to immediate release tablet formulation in terms of extent of absorption in rabbits. As the formulation showed delay in drug release bothin vitroandin vivo, nighttime administration could be beneficial to reduce the cardiovascular complications due to early morning surge in blood pressure.
Identification and Quantification of Aldose Reductase Inhibitory Flavonoids in Herbal Formulation and Extract of Gymnema sylvestre Using HPLC-PDA and LC-MS/MS
Authors: Satheeshkumar Nanjappan , Shantikumar Saladi , Komali Mopuri
Published: November 2014

Adulteration of herbal supplements is a major issue for many countries. A simple and reliable HPLC-PDA method was developed for quantification of aldose reductase inhibitory flavonoids rutin, quercetin, and kaempferol. The chromatographic separation was performed on a Fortis C18 column in gradient mode with detection at 267 nm. The presence of these markers was confirmed through the accurate m/z values and MS/MS data obtained using quadruple time of flight mass spectrometry (QTOF-MS). The proposed method was successfully applied to examine the amount of these active constituents in antiobese polyherbal formulation and plant extract of Gymnema sylvestre.
Size Dependent Optical Nonlinearity and Optical Limiting Properties of Water Soluble CdSe Quantum Dots
Authors: Augustine Anju K. , Mathew S. , Radhakrishnan P. , Nampoori V. P. N. , Kailasnath M.
Published: November 2014

We present third-order optical nonlinear absorption in CdSe quantum dots (QDs) with particle sizes in the range of 4.16–5.25 nm which has been evaluated by the Z-scan technique. At an excitation irradiance of 0.54 GW/cm2 the CdSe QDs exhibit reverse saturation indicating a clear nonlinear behavior. Nonlinearity increases with particle size in CdSe QDs within the range of our investigations which in turn depends on the optical band gap. The optical limiting threshold of the QDs varies from 0.35 GW/cm2 to 0.57 GW/cm2 which makes CdSe QDs a promising candidate for reverse-saturable absorption based devices at high laser intensities such as optical limiters.
Pairing-Free Certificateless Signature with Security Proof
Authors: Liu Wenhao , Xie Qi , Wang Shengbao , Han Lidong , Hu Bin
Published: November 2014

Since certificateless public key cryptosystem can solve the complex certificate management problem in the traditional public key cryptosystem and the key escrow problem in identity-based cryptosystem and the pairing computation is slower than scalar multiplication over the elliptic curve, how to design certificateless signature (CLS) scheme without bilinear pairings is a challenge. In this paper, we first propose a new pairing-free CLS scheme, and then the security proof is presented in the random oracle model (ROM) under the discrete logarithm assumption. The proposed scheme is more efficient than the previous CLS schemes in terms of computation and communication costs and is more suitable for the applications of low-bandwidth environments.