bluuebunny/crossref_metadata_2025 huggingface dataset:
Dietary supplementation with omega-3 polyunsaturated fatty acids ameliorates acute pneumonia induced byKlebsiella pneumoniaein BALB/c mice
Authors: Sharma Sonica , Chhibber Sanjay , Mohan Harsh , Sharma Saroj
Published: May 2013

The immune benefits associated with the optimal intake of dietary fatty acids are widely known. The objective of the present investigation was to elucidate the role of omega-3 polyunsaturated fatty acids (n-3 PUFA) food source on acute pneumonia induced by Klebsiella pneumoniae. Three different n-3 PUFA preparations (cod liver oil, Maxigard, and flaxseed oil) were orally supplemented and infection was induced in different groups of experimental mice. Mice fed olive oil and normal saline served as oil and saline controls, respectively. After 2 weeks of fatty acid feeding, no effect on the establishment of infection was observed when acute pneumonia was induced in animals. On the other hand, 6 weeks of n-3 PUFA administration was found to improve resistance in mice, as reduced lung bacterial load coupled with significant improvement in pathology was seen in infected mice. Alveolar macrophages collected from all 3 groups of mice fed n-3 PUFA exhibited a significant decrease in the level of apoptosis following infection with K. pneumoniae and an enhanced in vitro phagocytic potential for the pathogen. Lower lung levels of nitric oxide, malondialdehyde, and lactate dehydrogenase were associated with a decrease in the severity of tissue damage. There was a significant increase in the lung levels of pro-inflammatory cytokines (tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β)). No significant change was observed in the levels of interleukin-10 (IL-10). This study highlights that dietary n-3 PUFA supplementation exerts an overall beneficial effect against acute experimental pneumonia. This mechanism is operative through upregulation of nonspecific and specific immune defenses of the host.
OUTDOOR VIEW RECOGNITION BASED ON LANDMARK GROUPING AND LOGISTIC REGRESSION
Authors: TODT EDUARDO , TORRAS CARME
Published: May 2013

Vision-based robot localization outdoors has remained more elusive than its indoors counterpart. Drastic illumination changes and the scarceness of suitable landmarks are the main difficulties. This paper attempts to surmount them by deviating from the main trend of using local features. Instead, a global descriptor called landmark-view is defined, which aggregates the most visually-salient landmarks present in each scene. Thus, landmark co-occurrence and spatial and saliency relationships between them are added to the single landmark characterization, based on saliency and color distribution. A suitable framework to compare landmark-views is developed, and it is shown how this remarkably enhances the recognition performance, compared against single landmark recognition. A view-matching model is constructed using logistic regression. Experimentation using 45 views, acquired outdoors, containing 273 landmarks, yielded good recognition results. The overall percentage of correct view classification obtained was 80.6%, indicating the adequacy of the approach.
ON THE ROMAN BONDAGE NUMBER OF A GRAPH
Authors: BAHREMANDPOUR A. , HU FU-TAO , SHEIKHOLESLAMI S. M. , XU JUN-MING
Published: May 2013

A Roman dominating function (RDF) on a graph G = (V, E) is a function f : V → {0, 1, 2} such that every vertex v ∈ V with f(v) = 0 has at least one neighbor u ∈ V with f(u) = 2. The weight of a RDF is the value f(V(G)) = Σu∈V(G) f(u). The minimum weight of a RDF on a graph G is called the Roman domination number, denoted by γR(G). The Roman bondage number bR(G) of a graph G with maximum degree at least two is the minimum cardinality of all sets E′ ⊆ E(G) for which γR(G - E′) > γR(G). In this paper, we first show that the decision problem for determining bR(G) is NP-hard even for bipartite graphs and then we establish some sharp bounds for bR(G) and characterizes all graphs attaining some of these bounds.
A LOW-COST RANGE-FREE LOCALIZATION SCHEME FOR THREE-DIMENSIONAL UNDERWATER SENSOR NETWORKS
Authors: LU XIANLING , LI DEYING , HONG YI , CHEN WENPING
Published: May 2013

Localization is one of the fundamental tasks for underwater sensors networks (USNs). It is required for data tagging, target detection, route protocols, and so on. In this paper, we propose an efficient low-cost range-free localization scheme for 3D underwater sensor networks (3D-LRLS) without any additional hardware infrastructure. In our scheme, each anchor node has variable transmission power levels. At first, the power levels of each anchor are decided by the Delaunay triangulation for the network space. Then, ordinary sensors listen to the beacons sent from the anchor nodes. Based on the beacon messages, each node calculates its location individually by a low computational complexity method. The extensive simulation results demonstrate that 3D-LRLS is efficient in terms of both localization ratio and localization accuracy.
A NOVEL OPTIMIZATION APPROACH — FREE SEARCH WITH DOUBLE POPULATIONS
Authors: WEI YUEFEI , CHEN ZENGQIANG , LI YIBO , SUN QINGLIN
Published: May 2013

In this paper, an improved optimization approach, free search with double populations (FSDP) which is based on free search (FS) algorithm, is proposed. Comparing to FS algorithm, FSDP preserves the sub-optimal solutions and adopts elitist strategy in the searching process, which effectively avoids falling into local optimum and improves the convergence speed and the search accuracy. Simulation results show that FSDP has a better comprehensive performance over FS, PSO and GA.
HEURISTIC QUANTUM GENETIC ALGORITHM FOR AIR COMBAT DECISION MAKING ON COOPERATIVE MULTIPLE TARGET ATTACK
Authors: KONG HAIPENG , LI NI
Published: May 2013

In order to achieve the optimal attack outcome in the air combat under the beyond visual range (BVR) condition, the decision-making (DM) problem which is to set a proper assignment for the friendly fighters on the hostile fighters is the most crucial task for cooperative multiple target attack (CMTA). In this paper, a heuristic quantum genetic algorithm (HQGA) is proposed to solve the DM problem. The originality of our work can be supported in the following aspects: (1) the HQGA assigns all hostile fighters to every missile rather than fighters so that the HQGA can encode chromosomes with quantum bits (Q-bits); (2) the relative successful sequence probability (RSSP) is defined, based on which the priority attack vector is constructed; (3) the HQGA can heuristically modify quantum chromosomes according to modification technique proposed in this paper; (4) last but not the least, in some special conditions, the HQGA gets rid of the constraint described by other algorithms that to obtain a better result. In the end of this paper, two examples are illustrated to show that the HQGA has its own advantage over other algorithms when dealing with the DM problem in the context of CMTA.
REALISTIC AND CORRECT MODELS OF IMPRESSED SOURCES FOR TIME-HARMONIC ELECTROMAGNETIC BOUNDARY VALUE PROBLEMS INVOLVING METAMATERIALS
Authors: FERNANDES PAOLO , RAFFETTO MIRCO
Published: May 2013

The aim of this work is to analyze the role of the impressed sources in determining the well or ill-posedness of time harmonic electromagnetic boundary value problems involving isotropic effective media. It is shown, in particular, that, even if all interfaces are regular, the class of ill-posed problems can be very large in the presence of general square-integrable impressed sources. However, when a simple and realistic constraint is enforced on these sources, requiring that the support of the sources does not include any interface between a traditional medium and a metamaterial, among the problems here considered just those involving an interface between complementary materials remain ill-posed. These considerations have a very significant impact also on the approximability of the solution of well-posed problems since the numerical noise can introduce small fictitious sources even where the sources to be simulated are not present. These effects on finite element simulators are fully analyzed. Finally, we propose an algorithm that allows to obtain much better approximations of the solutions of the most critical well-posed problems.
HIGH ORDER ACCURATE QUINTIC NONPOLYNOMIAL SPLINE FINITE DIFFERENCE APPROXIMATIONS FOR THE NUMERICAL SOLUTION OF NON-LINEAR TWO POINT BOUNDARY VALUE PROBLEMS
Authors: JHA NAVNIT
Published: May 2013

We develop a new sixth-order accurate numerical scheme for the solution of two point boundary value problems. The scheme uses nonpolynomial spline basis and high order finite difference approximations. With the help of spline functions, we derive consistency conditions and it is used to derive high order discretizations of the first derivative. The resulting difference schemes are solved by the standard Newton's method and have very small computing time. The new method is analyzed for its convergence and the efficiency of the proposed scheme is illustrated by convection-diffusion problem and nonlinear Lotka–Volterra equation. The order of convergence and maximum absolute errors are computed to present the utility of the new scheme.
Near-invariant blur for depth and 2D motion via time-varying light field analysis
Authors: Bando Yosuke , Holtzman Henry , Raskar Ramesh
Published: May 2013

Recently, several camera designs have been proposed for either making defocus blur invariant to scene depth or making motion blur invariant to object motion. The benefit of such invariant capture is that no depth or motion estimation is required to remove the resultant spatially uniform blur. So far, the techniques have been studied separately for defocus and motion blur, and object motion has been assumed 1D (e.g., horizontal). This article explores a more general capture method that makes both defocus blur and motion blur nearly invariant to scene depth and in-plane 2D object motion. We formulate the problem as capturing a time-varying light field through a time-varying light field modulator at the lens aperture, and perform 5D (4D light field + 1D time) analysis of all the existing computational cameras for defocus/motion-only deblurring and their hybrids. This leads to a surprising conclusion that focus sweep, previously known as a depth-invariant capture method that moves the plane of focus through a range of scene depth during exposure, is near-optimal both in terms of depth and 2D motion invariance and in terms of high-frequency preservation for certain combinations of depth and motion ranges. Using our prototype camera, we demonstrate joint defocus and motion deblurring for moving scenes with depth variation.
Ubiquity symposium: Evolutionary computation and the processes of life
Authors: Zenil Hector , Marshall James A. R.
Published: May 2013

While evolution has inspired algorithmic methods of heuristic optimization, little has been done in the way of using concepts of computation to advance our understanding of salient aspects of biological phenomena. The authors argue under reasonable assumptions, interesting conclusions can be drawn that are of relevance to behavioral evolution. The authors will focus on two important features of life---robustness and fitness---which, they will argue, are related to algorithmic probability and to the thermodynamics of computation, disciplines that may be capable of modeling key features of living organisms, and which can be used in formulating new algorithms of evolutionary computation.
Big graph mining
Authors: Kang U. , Faloutsos Christos
Published: May 2013

How do we find patterns and anomalies in very large graphs with billions of nodes and edges? How to mine such big graphs efficiently? Big graphs are everywhere, ranging from social networks and mobile call networks to biological networks and the World Wide Web. Mining big graphs leads to many interesting applications including cyber security, fraud detection, Web search, recommendation, and many more.

In this paper we describe Pegasus, a big graph mining system built on top of MapReduce, a modern distributed data processing platform. We introduce GIM-V, an important primitive that Pegasus uses for its algorithms to analyze structures of large graphs. We also introduce HEigen, a large scale eigensolver which is also a part of Pegasus. Both GIM-V and HEigen are highly optimized, achieving linear scale up on the number of machines and edges, and providing 9.2x and 76x faster performance than their naive counterparts, respectively.

Using Pegasus, we analyze very large, real world graphs with billions of nodes and edges. Our findings include anomalous spikes in the connected component size distribution, the 7 degrees of separation in a Web graph, and anomalous adult advertisers in the who-follows-whom Twitter social network.
Membrane Microdomains, Rafts, and Detergent-Resistant Membranes in Plants and Fungi
Authors: Malinsky Jan , Opekarová Miroslava , Grossmann Guido , Tanner Widmar
Published: May 2013

The existence of specialized microdomains in plasma membranes, postulated for almost 25 years, has been popularized by the concept of lipid or membrane rafts. The idea that detergent-resistant membranes are equivalent to lipid rafts, which was generally abandoned after a decade of vigorous data accumulation, contributed to intense discussions about the validity of the raft concept. The existence of membrane microdomains, meanwhile, has been verified by unequivocal independent evidence. This review summarizes the current state of research in plants and fungi with respect to common aspects of both kingdoms. In these organisms, principally immobile microdomains large enough for microscopic detection have been visualized. These microdomains are found in the context of cell-cell interactions (plant symbionts and pathogens), membrane transport, stress, and polarized growth, and the data corroborate at least three mechanisms of formation. As documented in this review, modern methods of visualization of lateral membrane compartments are also able to uncover the functional relevance of membrane microdomains.
Readout of Epigenetic Modifications
Authors: Patel Dinshaw J. , Wang Zhanxin
Published: May 2013

This review focuses on a structure-based analysis of histone posttranslational modification (PTM) readout, where the PTMs serve as docking sites for reader modules as part of larger complexes displaying chromatin modifier and remodeling activities, with the capacity to alter chromatin architecture and templated processes. Individual topics addressed include the diversity of reader-binding pocket architectures and common principles underlying readout of methyl-lysine and methyl-arginine marks, their unmodified counterparts, as well as acetyl-lysine and phosphoserine marks. The review also discusses the impact of multivalent readout of combinations of PTMs localized at specific genomic sites by linked binding modules on processes ranging from gene transcription to repair. Additional topics include cross talk between histone PTMs, histone mimics, epigenetic-based diseases, and drug-based therapeutic intervention. The review ends by highlighting new initiatives and advances, as well as future challenges, toward the promise of enhancing our structural and mechanistic understanding of the readout of histone PTMs at the nucleosomal level.
Heterogeneity in the Dynamics of Labor Earnings
Authors: Browning Martin , Ejrnæs Mette
Published: May 2013

In this article, we survey the literature on individual earnings dynamics with a particular focus on allowing for pervasive heterogeneity across individuals. We structure the discussion around ARMA processes with nonlinear trends for each individual. We show that allowing for pervasive and codependent heterogeneity in individual parameters has a major impact on econometric modeling, estimation, and substantive conclusions. We describe an econometric method that is suitable for models with pervasive heterogeneity. We develop a long list of statistics that describe any earnings panel in great detail and provide a demanding set of features of the data for fitting. This list encompasses most moments used in the literature and provides novel statistics based on individual regressions. Finally, we present an empirical illustration using a long Danish panel. Based on this, we provide some conclusions concerning earnings dynamics but emphasize that details will vary according to the sample.
Financial Literacy, Financial Education, and Economic Outcomes
Authors: Hastings Justine S. , Madrian Brigitte C. , Skimmyhorn William L.
Published: May 2013

In this article, we review the literature on financial literacy, financial education, and consumer financial outcomes. We consider how financial literacy is measured in the current literature and examine how well the existing literature addresses whether financial education improves financial literacy or personal financial outcomes. We discuss the extent to which a competitive market provides incentives for firms to educate consumers or to offer products that facilitate informed choice. We review the literature on alternative policies to improve financial outcomes and compare the evidence with that on the efficacy and cost of financial education. Finally, we discuss directions for future research.
Electronic-Structure Theory of Organic Semiconductors: Charge-Transport Parameters and Metal/Organic Interfaces
Authors: Coropceanu Veaceslav , Li Hong , Winget Paul , Zhu Lingyun , Brédas Jean-Luc
Published: May 2013

We focus this review on the theoretical description, at the density functional theory level, of two key processes that are common to electronic devices based on organic semiconductors (such as organic light-emitting diodes, field-effect transistors, and solar cells), namely charge transport and charge injection from electrodes. By using representative examples of current interest, our main goal is to introduce some of the reliable theoretical methodologies that can best depict these processes. We first discuss the evaluation of the microscopic parameters that determine charge-carrier transport in organic molecular crystals, i.e., electronic couplings and electron-vibration couplings. We then examine the electronic structure at interfaces between an organic layer and a metal or conducting oxide electrode, with an emphasis on the work-function modifications induced by the organic layer and on the interfacial energy-level alignments.
Cocoa and Human Health
Authors: Ellam Samantha , Williamson Gary
Published: May 2013

Cocoa is a dry, powdered, nonfat component product prepared from the seeds of the Theobroma cacao L. tree and is a common ingredient of many food products, particularly chocolate. Nutritionally, cocoa contains biologically active substances that may affect human health: flavonoids (epicatechin and oligomeric procyanidins), theobromine, and magnesium. Theobromine and epicatechin are absorbed efficiently in the small intestine, and the nature of their conjugates and metabolites are now known. Oligomeric procyanidins are poorly absorbed in the small intestine, but catabolites are very efficiently absorbed after microbial biotransformation in the colon. A significant number of studies, using in vitro and in vivo approaches, on the effects of cocoa and its constituent flavonoids have been conducted. Most human intervention studies have been performed on cocoa as an ingredient, whereas many in vitro studies have been performed on individual components. Approximately 70 human intervention studies have been carried out on cocoa and cocoa-containing products over the past 12 years, with a variety of endpoints. These studies indicate that the most robust biomarkers affected are endothelial function, blood pressure, and cholesterol level. Mechanistically, supporting evidence shows that epicatechin affects nitric oxide synthesis and breakdown (via inhibition of nicotinamide adenine di-nucleotide phosphate oxidase) and the substrate arginine (via inhibition of arginase), among other targets. Evidence further supports cocoa as a biologically active ingredient with potential benefits on biomarkers related to cardiovascular disease. However, the calorie and sugar content of chocolate and its contribution to the total diet should be taken into account in intervention studies.
The Political Economy of Fishery Reform
Authors: Grainger Corbett A. , Parker Dominic P.
Published: May 2013

Despite compelling evidence that property rights–based management can improve the economic and ecological performance of fisheries, reform proposals are often met with political opposition. Moreover, the opposition sometimes comes from incumbent fishermen and fishing communities that would ostensibly gain the most from rent-enhancing reforms. We flesh out this puzzle by describing the political economy of past and present institutional changes in North America such as bans on fish traps, limited-entry regulations, and individual transferable quotas (ITQs). Our review identifies patterns of distributional concerns surrounding property rights; many of the same groups that opposed limits on entry and fish traps also oppose ITQs. We provide examples of how political opposition to ITQs is mollified by modifications in program design, although these design compromises may have efficiency costs. We conclude by pointing to the need for more research on equity-efficiency trade-offs and for greater attention to fishermen heterogeneity in economic analysis.
Thermally Activated Emission from Direct Bandgap-Like Silicon Quantum Dots
Authors: Dohnalova Katerina , Saeed Saba , Poddubny Alexander N , Prokofiev Alexei A , Gregorkiewicz Tom
Published: May 2013

Due to the covalent character of silicon-carbon (Si-C) bond, C- linked molecules on the silicon quantum dot (SiQD) surface lead to dramatic changes in wavefunctions of the excited electron-hole pairs. Some of the optical transitions are strongly modified and attain direct bandgap-like character, giving rise to bright phonon-less fast decaying emission, while many other transitions keep their typical indirect bandgap character. It appears that in C-terminated SiQDs, with diameter larger than ~2 nm, the most efficient recombination occurs from states slightly above the ground state. This leads to thermal activation of the fast emission, dominating the photoluminescence from these SiQDs. On the other hand, in the smallest SiQDs of less than 2 nm, the lowest excited states have the direct bandgap-like character and therefore their emission becomes gradually dominant at lower temperatures, as indeed supported by our experimental observations.
(Invited) Optimizing Er-Doped Layer Stacks for Integrated Light Emitting Devices
Authors: Ramírez Joan Manel , Berencén Yonder , López-Conesa Luis , Rebled Jose Maria , Eljarrat Alberto , Estradé Sonia , Peiró Francisca , Fedeli J. M. , Garrido Blas
Published: May 2013

A detailed itinerary of our main results and current advances in Er-doped light emitting devices are here reported. We start with the photoluminescence, then the electrical characterization and the electroluminescence of Er-doped capacitors and active slot waveguides. Finally a summary of the ongoing work focused on the combination of Er-doped semiconductor superlattices with more complex devices such as slot-based ring resonators or metal-oxide-semiconductor-field-effect transistors is presented
(Invited) Ballistic Electron Effects in Nanosilicon and Their Applications
Authors: Koshida Nobuyoshi , Ikegami Naokatsu I , Kojima Akira , Mentek Romain , Gelloz Bernard
Published: May 2013

In nanocrystalline silicon (nc-Si) dots interconnected with tunnel oxides, the characteristic electron transport mode appears followed by highly hot electron effects: avalanche photoconduction and quasi-ballistic electron emission. Analysis of the former clarifies that the impact ionization rate in nc-Si dots is considerably higher than in bulk Si. The usefulness of the latter has been confirmed in various media. A typical example of the application in vacuum is the use as the excitation source for parallel electron beam lithography. Another potential is induced by the operation in aqueous and metal salt solutions, where the highly reducing reaction proceeds at the emitter surface. In SiCl4 and GeCl4 solutions, for instance, thin Si and Ge films are deposited without the use of any counter electrodes. Some topics of these effects are discussed here.
(Invited) Nanocrystals Embedded High-k Nonvolatile Memories – Bulk Film and Nanocrystal Material Effects
Authors: Kuo Yue
Published: May 2013

The principle of the nanocrystals embedded high-k nonvolatile memory device has been reviewed. The high-k stack could be fabricated with a simple and low cost one pumpdown sputtering method followed by rapid thermal annealing. The memory function of the device is controlled by material properties of the high-k and the embedded nanocrystal. Factors influencing the type of trapped charges, the charge trapping capacity, and reliability with respect to operation parameters and environment are discussed. This kind of device is potentially important for high density and highly reliable electronic products.
Improved Performance of Silicon Nanocrystal Memories for Application Working Over a Wide Range of Temperature
Authors: Della Marca Vincenzo , Amouroux Julien , Molas Gabriel , Postel-Pellerin Jérémy , Lalande Frédéric , Boivin Philippe , Ogier Jean-Luc
Published: May 2013

The microelectronic industry requires more and more low consumption and high reliability solutions. In this scenario the silicon nanocrystal memories (Si-nc) are one of the most mature technologies able to replace the Flash floating gate in NOR embedded applications. The main advantages of Si-nc memories are: the full compatibility with the CMOS process using a reduced number of masks (1) and the robustness against SILC (2). In this paper we present an experimental work on the optimized silicon nanocrystal cell industrially manufactured, where the reliability is improved (3). In particular the impact of silicon nanocrystals size and temperature on cell programming window is shown. Moreover we demonstrated for the first time at our knowledge that it is possible to achieve 1Mcycles endurance characteristic in the temperature range of [-40°C; 150°C], programming by channel hot electron (CHE) and erasing by Fowler-Nordheim (FN).
(Invited) Electrical Conductivity Bistability in Nano-Composite
Authors: Prime Dominic C. , Al Halafi Zahra , Green Mark A , Salaoru Iulia , Paul Shashi
Published: May 2013

Nano-composite polymer memory devices are fabricated by depositing a blend (an admixture of organic polymer, small organic molecules and nanoparticles) between two metal electrodes. These devices show two electrical conductance states (“1” and “0”) when voltage is applied, thus rendering the structures suitable for data retention. These two states can be viewed as the realisation of non-volatile memory. Nano-composite polymer memory devices comprising of a blend of a polymer and small molecules and/or nanoparticles are investigated. This study is aimed at further understanding the electrical bistability observed in such devices. This work also investigates if an electrical charge can be transferred to gold nano-particles and, between small molecule complexes.
Characteristics of Fluorine-Doped Tin Oxide as a Transparent Heater on PET Prepared by ECR-MOCVD
Authors: Hudaya Chairul , Park Ji Hun , Choi Wonchang , Lee Joong Kee
Published: May 2013

The flexible transparent heater of fluorine-doped tin oxide (FTO) thin films on a polyethylene terephthalate (PET) was prepared by electron cyclotron resonance – metal organic chemical vapor deposition (ECR-MOCVD). Under plasma environment, the films were fabricated by supplying tetra-methyl tin (TMT) as precursors for tin, sulfur-hexafluorides (SF6) as precursor for fluorine atoms, oxygen and hydrogen for about 15 min deposition. The result shows that the FTO films have nanocrystalline structure with a grain size of 30-60 nm, a thickness of 300 nm and transmittance over 85 %. The observed lowest sheet resistance of 253 Ω/□ was found in our experimental range. We conclude the optimum fluorine doping plays an important role to affect the structural, electrical, optical and thermal properties of the FTO thin films as transparent materials.
Sharp Switching SOI Devices
Authors: Cristoloveanu Sorin , Wan Jing , Le Royer Cyrille , Zaslavsky Alexander
Published: May 2013

We present two classes of sharp-switching SOI devices: tunneling FETs (TFETs) and feedback transistors. The TFET is a reverse-biased pin gated diode: gate voltage VG controls the electric field in the interband p+/n+ tunneling junction. In principle, the TFET current can be switched faster than thesubthreshold current of a MOSFET. We will review technologicalsolutions for improving the ION current and subthreshold swing. The recently proposed feedback transistor has a similar gated-diode configuration, but operated in forward bias. Electrostatic gate-controlled barriers prevent carrier injection into the channel until the gate bias reaches a turn-on value, at which point the device switches abruptly (< 1 mV/decade) to a high ION current. We will discuss the device physics, architecture, and outstanding performance of the Z2-FET variant, with applications in CMOS-compatible memories, sensors, logicand protection circuits.
Sharp-Switching High-Current Tunneling Devices
Authors: Zaslavsky Alexander , Wan Jing , Le Son T. , Jannaty P. , Cristoloveanu Sorin , Le Royer Cyrille , Perea D. E. , Dayeh Shadi A. , Picraux S. T.
Published: May 2013

Tunneling FETs (TFETs) offer the possibility of overcoming the 60 mV/dec subthreshold slope limit of conventional transistors and thereby providing sharp-switching logic devices. We discuss two approaches to increasing the current drive of tunneling devices, both implemented in the silicon-germanium heterostructure system. First, the bipolar-enhanced TFET (BET-FET) multiplies the gate-controlled interband tunneling current by the Si/Ge heterojunction bipolar current gain. Both vertical and planar versions have been simulated, with high I
ON > 1000 mA/mm accompanying low subthreshold swing over many decades of current. Second, the trigate Si/Ge heteronanowire TFET is based on shifting the tunneling junction from Ge in the on-state to Si in the off-state. Fabricated with a vapor-liquid-solid epitaxial Si/Ge hetero-nanowire channel and high-k dielectric trigate stack, the proof-of-concept prototype device exhibits reasonable I
ON, sub-60 mV/dec slope, as well as surprising backgating properties.
Impact of Disturb on Retention Time in Single FBRAM Cells
Authors: dos Santos S. D. , Nicoletti T. , Martino J. A. , Aoulaiche M. , Jurczak M. , Simoen E. , Claeys C.
Published: May 2013

This manuscript presents an investigation of the wordline (WL) and bitline (BL) voltage disturb based on a single floating body random access memory (FBRAM) cell. It is found that several physical mechanisms can disturb the stored charge either fully or partially. The worst cases for disturb are shown and the disturb window for BL and WL are characterized for further operating condition optimization. Moreover, it is shown that in the very dense memory coupling between bitlines or wordlines will spread the disturb even to cells which are not sharing the same BL and WL.
Analog Behavior of Submicron Graded-Channel SOI MOSFETs Varying Channel Length, Doping Concentration and Temperature
Authors: Nemer J. P. , de Souza M. , Flandre D. , Pavanello M. A.
Published: May 2013

In this paper the analog performance of Graded-Channel (GC) SOI nMOSFETs with deep submicrometer channel length is presented. Experimental data of GC transistors fabricated in an industrial 150 nm fully-depleted SOI technology from OKI Semiconductorswere used to adjust the two-dimensional numerical simulations, in order to analyze the devices analog behavior by extrapolating their physical parameters. The obtained results show that the larger intrinsic voltage gain improvement occurs when the length of the lightly doped region is approximately 100 nm regardless the total channel length, doping concentration and temperature.
Spin Lifetime Enhancement by Shear Strain in Thin Silicon-On-Insulator Films
Authors: Osintsev Dmitri , Sverdlov Viktor , Selberherr Siegfried
Published: May 2013

Spintronics attracts at present much interest because of the potential to build novel spin-based devices which are superior to nowadays charge-based microelectronic elements. Utilizing spin properties of electrons opens great opportunities to reduce device power consumption in future electronic circuits. Silicon, the main element of microelectronics, is promising for spin-driven applications. Understanding the details of the spin propagation in silicon structures is a key for building novel spin-based nanoelectronic devices. We investigate the influence of shear strain on surface roughness induced spin relaxation in a thin silicon-on-insulator-based transistor. Shear strain dramatically influences the spin, which opens a new opportunity to boost spin lifetime in a silicon spin field-effect transistor.
Characteristics Of SnSbSe (SSS) Thin Films Grown by Atomic Layer Deposition for High Performance Phase Change Random Access Memory (PCRAM)
Authors: Lee Keun , Kang Sehun , Ku Jachun , Hong Kwon , Park Sungki
Published: May 2013

Characteristics of SSS(SnSbSe) thin films grown by atomic layer deposition(ALD) were investigated for high performance phase change random access memory(PCRAM). Adopting super-cycle concept which consist of SbSe binary and Sn single sub-cycle and adjusting Sb/Se exposure ratio, stoichiometry was successfully controlled. Microstructure and crystallization speed of ALD Sn-doped Sb-rich SbSe films were confirmed. Furthermore, ALD SSS film showed excellent gap-filling performance using confined cell structure of aspect ratio 5.0 (cell dimension 15nm).
Changes in the Electrochemical Behavior of Silicon after Platinum Deposition and Ionic Bombardment
Authors: Hervier Antoine , Aureau Damien , Etcheberry Arnaud
Published: May 2013

The electrochemical response of thin Pt films on Si was studied at different stages of mixing between Pt and Si, from fully segregated to fully mixed. This phase change was induced by subjecting the films to helium ion bombardment at energies in the range of 30 keV. The formation of a PtxSi phase was confirmed by XPS measurements. As the bombardment dose increases, the voltammogram peaks characteristic of bulk platinum eventually disappear, giving way to the practically featureless voltammogram of electrocatalytically inactive platinum silicide.
High Power Density Redox Flow Battery Cells
Authors: Perry Mike L. , Darling Robert M. , Zaffou Rachid
Published: May 2013

Redox flow batteries possess several key advantages that make them well suited for grid-scale energy-storage applications. However, the capital cost of flow batteries has been a major barrier to commercialization of this technology. One attractive path to cost reduction is the development of flow-battery cells with substantially higher power densities than conventional flow-battery cells. The cost of the cells comprises a significant portion of the total flow-battery system cost, especially at low production volumes, since cell parts are custom-built components. UTRC has developed high power density vanadium-redox battery cells utilizing a material set similar to conventional cells. This advanced cell technology can theoretically be applied to other flow-battery chemistries as well. This breakthrough in cell performance should motivate additional development of flow-battery technologies, since a realistic path to substantial cost reduction, which can be realized even at low production volumes, has now been demonstrated.
Dynamic Modeling of Community Energy Storage for Lifetime Estimation During Islanding
Authors: Fares Robert L. , Webber Michael E.
Published: May 2013

This paper implements a dynamic model of “community energy storage,” a 25 kWh transformer-level battery system, to show its ability to island downstream electric loads during a grid outage. We utilize one-minute electric demand and rooftop photovoltaic generation data collected in Austin, Texas with the dynamic model to quantify how long community energy storage could island downstream loads before its minimum cutoff voltage is reached and it is brought offline. Our results show that photovoltaics nearly triple the average islanding lifetime of community energy storage during outages occurring in the morning, highlighting the symbiosis between distributed energy storage and distributed photovoltaic generation.
Study of the Electrochemical Behavior of High Voltage Vanadium-Metal Hydride Hybrid Semi-Flow Battery
Authors: Weng Guo-Ming , Li Chi-Ying Vanessa , Chan Kwong-Yu
Published: May 2013

A vanadium-MH rechargeable semi-flow battery hybridizing the V4+/V5+ redox couple (positive) with the metal hydride (negative) was investigated. This battery has a higher cell voltage and the V(II)/V(III) redox couple is absent, hence avoiding the problems of V2+ oxidation. An experimental open circuit voltage of 1.86 V and an operating voltage of 1.65 V for this hybrid battery were obtained. These are very high values among all rechargeable flow batteries. The system demonstrated superior stability, reversibility, and efficiencies in coulomb (97%), energy (81.3%), and voltage (83.8%).
Numerical and Analytic Modeling of a Membraneless Hydrogen Bromine Laminar Flow Batter
Authors: Braff William A. , Buie Cullen R. , Bazant Martin Z.
Published: May 2013

The current-voltage performance of a membrane-less Hydrogen Bromine Laminar Flow Battery is examined in the context of numerical and analytic models. A numerical finite element model of the system has been constructed and examined in order to better understand the potential and limitations of this system. An analytic description of the system has also been derived and solved to provide a broadly applicable, computationally inexpensive tool that is can be used to understand and optimize the performance of a wide range of membrane-less laminar flow electrochemical cells.
Asymmetric Performance Testing of Carbon Felt Electrodes to Identify the Limiting Electrode in Vanadium Redox Flow Battery
Authors: Agar Ertan , Dennison Christopher R. , Knehr Kevin W. , Kumbur Emin Caglan
Published: May 2013

In this study, the performance of a vanadium redox flow battery (VRFB) is measured with raw and heat-treated electrodes using symmetric (i.e., same electrode used in both half-cell) and asymmetric electrode configuration (i.e., different electrodes used in positive and negative half-cells). The goal with these tests is to determine the effects of the surface functionalization on the half-cell reactions and identify the half-cell that limits the performance of a VRFB. Results indicate that surface functionalization has a minimal impact on the reaction kinetics at the positive half-cell; however it substantially affects the reaction kinetics of the negative half-cell, suggesting that the negative half-cell electrode may limit the performance of these systems.
Novel Quinone-Based Couples for Flow Batteries
Authors: Huskinson Brian , Nawar Saraf , Gerhardt Michael R , Aziz Michael J.
Published: May 2013

Flow batteries are of interest for low-cost grid-scale electrical energy storage in the face of rising electricity production from intermittent renewables like wind and solar. We report on investigations of redox couples based on the reversible protonation of small organic molecules called quinones. These molecules can be very inexpensive and may therefore offer a low cost per kWh of electrical energy storage. Furthermore they are known to rapidly undergo oxidation and reduction with high reversibility under some conditions, suggesting the possibility of high current density operation, which could lead to low cost per kW. We report cyclic voltammetry measurements for 1,4-parabenzoquinone in neutral pH aqueous solution using a three-electrode setup. We report full fuel cell measurements as well, utilizing p-benzoquinone in an acidic solution as a positive electrode material and a hydrogen negative electrode, where current densities in excess of 240 mA cm-2 have been achieved to date. These initial results indicate that the quinone/hydroquinone redox couple is a promising candidate for use in redox flow batteries.
TRPM5-dependent amiloride- and benzamil-insensitive NaCl chorda tympani taste nerve response
Authors: Ren ZuoJun , Rhyu Mee-Ra , Phan Tam-Hao T. , Mummalaneni Shobha , Murthy Karnam S. , Grider John R. , DeSimone John A. , Lyall Vijay
Published: May 2013

Transient receptor potential (TRP) subfamily M member 5 (TRPM5) cation channel is involved in sensing sweet, bitter, umami, and fat taste stimuli, complex-tasting divalent salts, and temperature-induced changes in sweet taste. To investigate if the amiloride- and benzamil (Bz)-insensitive NaCl chorda tympani (CT) taste nerve response is also regulated in part by TRPM5, CT responses to 100 mM NaCl + 5 μM Bz (NaCl + Bz) were monitored in Sprague-Dawley rats, wild-type (WT) mice, and TRP vanilloid subfamily member 1 (TRPV1) and TRPM5 knockout (KO) mice in the presence of resiniferatoxin (RTX), a TRPV1 agonist. In rats, NaCl + Bz + RTX CT responses were also monitored in the presence of triphenylphosphine oxide, a specific TRPM5 blocker, and capsazepine and N-(3-methoxyphenyl)-4-chlorocinnamid (SB-366791), specific TRPV1 blockers. In rats and WT mice, RTX produced biphasic effects on the NaCl + Bz CT response, enhancing the response at 0.5–1 μM and inhibiting it at >1 μM. The NaCl + Bz + SB-366791 CT response in rats and WT mice and the NaCl + Bz CT response in TRPV1 KO mice were inhibited to baseline level and were RTX-insensitive. In rats, blocking TRPV1 by capsazepine or TRPM5 by triphenylphosphine oxide inhibited the tonic NaCl + Bz CT response and shifted the relationship between RTX concentration and the magnitude of the tonic CT response to higher RTX concentrations. TRPM5 KO mice elicited no constitutive NaCl + Bz tonic CT response. The relationship between RTX concentration and the magnitude of the tonic NaCl + Bz CT response was significantly attenuated and shifted to higher RTX concentrations. The results suggest that pharmacological or genetic alteration of TRPM5 activity modulates the Bz-insensitive NaCl CT response and its modulation by TRPV1 agonists.
Tetrahydrobiopterin deficiency induces gastroparesis in newborn mice
Authors: Welsh Christopher , Enomoto Masahiro , Pan Jingyi , Shifrin Yulia , Belik Jaques
Published: May 2013

Pyloric stenosis, the most common infant gastrointestinal disease, has no known etiology and clinically presents as abnormal gastric emptying with evidence of pyloric muscle hypertrophy. Whether abnormalities in gastric muscle contraction and/or relaxation have a role in this condition is poorly known, but gastroparesis is commonly observed in association with delayed gastric emptying in adults. Therefore, we evaluated the tetrahydrobiopterin (BH4)-deficient newborn mouse model of this disease ( hph-1) and hypothesized that their gastric muscle properties are impaired, when compared with wild-type control animals. In vitro studies evaluating the age-dependent gastric fundus muscle contraction and relaxation potential were conducted. Compared with wild-type mice, the hph-1 stomach content/body weight ratio was significantly increased in newborn but not juvenile or adult animals, confirming abnormal gastric emptying. Gastric tissue neuronal nitric oxide synthase (nNOS) protein expression was upregulated in both newborn and adult hph-1 mice, but in the former there was evidence of enzyme uncoupling and higher tissue superoxide generation when compared with same age-matched animals. As opposed to the lack of strain differences in the U46619-induced force, the newborn hph-1 gastric muscle carbachol-induced contraction and nNOS-dependent relaxation were significantly reduced ( P < 0.01). These group differences were not present in juvenile or adult mice. Preincubation with BH4 significantly enhanced the newborn hph-1, but not wild-type, gastric muscle contraction. In conclusion, changes compatible with gastroparesis are present in the newborn mouse model of pyloric stenosis. The role of BH4 deficiency and possibly associated gastroparesis in the pathogenesis of infantile pyloric stenosis warrants further investigation.
Muscle metabolic determinants of exercise tolerance following exhaustion: relationship to the “critical power”
Authors: Chidnok Weerapong , Fulford Jonathan , Bailey Stephen J. , DiMenna Fred J. , Skiba Philip F. , Vanhatalo Anni , Jones Andrew M.
Published: May 2013

We tested the hypothesis that muscle high-energy phosphate compounds and metabolites related to the fatigue process would be recovered after exhaustion during recovery exercise performed below but not above critical power (CP) and that these changes would influence the capacity to continue exercise. Eight male subjects completed single-leg, knee-extension exercise to exhaustion (for ∼180 s) on three occasions, followed by a work-rate reduction to severe-intensity exercise, heavy-intensity exercise (<CP), or a 10-min passive recovery period, in random order. The muscle metabolic responses to exercise were assessed using 31P magnetic resonance spectroscopy. There was a significant difference between the sustainable exercise duration during the recovery from exhaustive exercise between the CP conditions (at least 10 min and 39 ± 31 s, respectively; P < 0.05). During passive recovery and <CP recovery exercise, muscle phosphocreatine concentration ([PCr]) increased rapidly after the exhaustion point, reaching ∼96% and ∼76% of baseline values, respectively, after 10 min ( P < 0.05). Moreover, pH increased abruptly, reaching 7.0 ± 0.0 and 7.0 ± 0.2, respectively, after 10 min recovery ( P < 0.05). However, during >CP recovery exercise, neither muscle [PCr] nor pH recovered, reaching ∼37% of the initial baseline and 6.6 ± 0.2, respectively. These results indicate that the muscle metabolic dynamics in recovery from exhaustive >CP differ according to whether the recovery exercise is performed below or above the CP. These findings confirm the importance of the CP as an intramuscular metabolic threshold that dictates the accumulation of fatigue-related metabolites and the capacity to tolerate high-intensity exercise.
Comparison of cardiovascular and biomechanical parameters of supine lower body negative pressure and upright lower body positive pressure to simulate activity in 1/6 G and 3/8 G
Authors: Schlabs Thomas , Rosales-Velderrain Armando , Ruckstuhl Heidi , Stahn Alexander C. , Hargens Alan R.
Published: May 2013

For future space exploration missions, it is important to determine the best method of simulating on Earth cardiovascular and biomechanical conditions for lunar and Martian gravities. For this purpose, we compared exercise performed within a lower body negative pressure (LBNP) and a lower body positive pressure (LBPP) chamber. Twelve subjects underwent a protocol of resting and walking (0.25 Froude) within supine LBNP and upright LBPP simulation. Each protocol was performed in simulated 1/6 G and 3/8 G. We assessed heart rate (HR), mean arterial blood pressure, oxygen consumption (V̇o2), normalized stride length, normalized vertical peak ground reaction force, duty factor, cadence, perceived exertion (Borg), and comfort of the subject. A mixed linear model was employed to determine effects of the simulation on the respective parameters. Furthermore, parameters were compared with predicted values for lunar and Martian gravities to determine the method that showed the best agreement. During walking, all cardiovascular and biomechanical parameters were unaffected by the simulation used for lunar and Martian gravities. During rest, HR and V̇o2were lower in supine LBNP compared with upright LBPP. HR, V̇o2, and normalized vertical peak ground reaction force obtained with supine LBNP and upright LBPP showed good agreement with predicted values. Since supine LBNP and upright LBPP are lacking significant differences, we conclude that both simulations are suited to simulate the cardiovascular and biomechanical conditions during activity in lunar and Martian gravities. Operational characteristics and the intended application should be considered when choosing either supine LBNP or upright LBPP to simulate partial gravities on Earth.