bluuebunny/crossref_metadata_2025 huggingface dataset:
System-level calibration for data fusion in wireless sensor networks
Authors: Tan Rui , Xing Guoliang , Yuan Zhaohui , Liu Xue , Yao Jianguo
Published: June 2013

Wireless sensor networks are typically composed of low-cost sensors that are deeply integrated in physical environments. As a result, the sensing performance of a wireless sensor network is inevitably undermined by biases in imperfect sensor hardware and the noises in data measurements. Although a variety of calibration methods have been proposed to address these issues, they often adopt the
device-level
approach that becomes intractable for moderate-to large-scale networks. In this article, we propose a two-tier
system-level
calibration approach for a class of sensor networks that employ data fusion to improve the sensing performance. In the first tier of our calibration approach, each sensor learns its local sensing model from noisy measurements using an online algorithm and only transmits a few model parameters. In the second tier, sensors' local sensing models are then calibrated to a common system sensing model. Our approach fairly distributes computation overhead among sensors and significantly reduces the communication overhead of calibration compared with the device-level approach. Based on this approach, we develop an
optimal
model calibration scheme that maximizes the target detection probability of a sensor network under bounded false alarm rate. Our approach is evaluated by both experiments on a testbed of TelosB motes and extensive simulations based on synthetic datasets as well as data traces collected in a real vehicle detection experiment. The results demonstrate that our system-level calibration approach can significantly boost the detection performance of sensor networks in scenarios with low signal-to-noise ratios.
Localization with sparse acoustic sensor network using UAVs as information-seeking data mules
Authors: Klein Daniel J. , Venkateswaran Sriram , Isaacs Jason T. , Burman Jerry , Pham Tien , Hespanha João , Madhow Upamanyu
Published: June 2013

We propose and demonstrate a novel architecture for on-the-fly inference while collecting data from sparse sensor networks. In particular, we consider source localization using acoustic sensors dispersed over a large area, with the individual sensors located too far apart for direct connectivity. An Unmanned Aerial Vehicle (UAV) is employed for collecting sensor data, with the UAV route adaptively adjusted based on data from sensors already visited, in order to minimize the time to localize events of interest. The UAV therefore acts as a information-seeking data mule, not only providing connectivity, but also making Bayesian inferences from the data gathered in order to guide its future actions. The system we demonstrate has a modular architecture, comprising efficient algorithms for acoustic signal processing, routing the UAV to the sensors, and source localization. We report on extensive field tests which not only demonstrate the effectiveness of our general approach, but also yield specific practical insights into GPS time synchronization and localization accuracy, acoustic signal and channel characteristics, and the effects of environmental phenomena.
Distributed and compact routing using spatial distributions in wireless sensor networks
Authors: Sarkar Rik , Zhu Xianjin , Gao Jie
Published: June 2013

In traditional routing, the routing tables store shortest paths to all other destinations and have size linear in the size of the network, which is not scalable for resource-constrained networks such as wireless sensor networks. In this article we show that by storing selectively a much smaller set of routing paths in the routing tables one can get low-stretch, compact routing schemes.

Our routing scheme includes an approximate distance oracle with which one can obtain approximate shortest path length estimates to destinations. This distance oracle can be obtained, for example, by a landmark-based scheme, or in case of sensor networks, from the geographic distance between node locations. With an approximate distance oracle one can attempt
greedy routing
by forwarding to the neighbor whose estimate is closer to the destination. But there is no guarantee of delivery nor of the routing path length. We augment the distance oracle by storing, for each node
u
, routing paths to
O
(log
2
n
) strategically selected nodes that serve as intermediate destinations. These nodes are selected with probability proportional to 1/
r
ρ
, where
r
is the distance to
u
and ρ is a suitable constant for the network. Then we derive a set of sufficient conditions to select the next step at each stage of routing, such that these conditions can be verified locally and guarantee 1+ε stretch routing on any metric. These conditions serve as the “greedy routing” or local decision rule.

On graphs of bounded growth, our scheme guarantees 1+ε stretch routing with high probability, with an average routing table size of
O
(√n log
2
n
). This scheme is favorable for its simplicity, generality, and blindness to any global state. It demonstrates that global routing properties could emerge from purely distributed and uncoordinated routing table design.
Adaptive energy-efficient scheduling for hierarchical wireless sensor networks
Authors: Li Wei , Delicato Flávia C. , Zomaya Albert Y.
Published: June 2013

Most Wireless Sensor Network (WSN) applications require distributed signal and collaborative data processing. One of the critical issues for enabling collaborative processing in WSNs is how to schedule tasks in a systematic way, including assigning tasks to sensor nodes, and determining their execution and communication sequence. Since WSN nodes are very resource constrained, mainly regarding their energy supply, one major concern when scheduling tasks in such environments is to minimize and balance the energy consumption, so that the system operational lifetime is maximized. We propose a heuristic-based three-phase algorithm (TPTS) for allocating tasks to multiple clusters in hierarchical WSNs that aims at finding a scheduling scheme that minimizes the overall energy consumption and balances the workload of the system while meeting the application's deadline. The performance of the proposed algorithm and the effect of several parameters on its behavior were evaluated by simulations, with promising results. The experimental results show that the time and energy performance of TPTS are close to the time and energy of benchmarks in most cases, while load balance is always provided.
Property management in wireless sensor networks with overcomplete radon bases
Authors: Jiang Xiaoye , Li Mo , Yao Yuan , Guibas Leonidas
Published: June 2013

This article presents a scalable algorithm for managing property information about moving objects tracked by a sensor network. Property information is obtained via distributed sensor observations, but will be corrupted when objects mix up with each other. The association between properties and objects then becomes ambiguous. We build a novel representation framework, exploiting an overcomplete Radon basis dictionary to model property uncertainty in such circumstances. By making use of the combinatorial structure of the basis design and sparse representations we can efficiently approximate the underlying probability distribution of the association between target properties and tracks, overcoming the exponential space that would otherwise be required. Based on the proposed theories, we design a fully distributed algorithm on wireless sensor networks. We conduct comparative simulations and the results validate the effectiveness of our approach.
An integrated development platform of a reconfigurable radio processor for software defined radio
Authors: Saha Amrita , Biswas Pijush , Sinha Amitabha
Published: June 2013

Performance required by "Software Defined Radio (SDR)" poses many challenges in real-time applications because of their high computational complexity. Designing a high performance SDR with a high degree of flexibility becomes an issue of importance. While the fastest programmable DSP processors are unable to meet the speed requirements for SDR, FPGAs also cannot offer the highest possible performance at the lowest silicon cost for a given signal processing function. Moreover, they are not optimized for radio applications because of their LUT based approach. To overcome the limitations of both DSP Processor and FPGAs, Radio Processor, a reconfigurable Processor optimized for Radio applications was conceived.[14],[17]. However, advantages of this Radio Processor cannot be made useful unless there is an integrated development environment to develop SDR. This paper addresses these issues by introducing a new Integrated Development platform for reconfigurable "Radio Processor" for implementing SDR.
Activation of the amino acid response modulates lineage specification during differentiation of murine embryonic stem cells
Authors: Shan Jixiu , Hamazaki Takashi , Tang Tiffany A. , Terada Naohiro , Kilberg Michael S.
Published: June 2013

In somatic cells, a collection of signaling pathways activated by amino acid limitation have been identified and referred to as the amino acid response (AAR). Despite the importance of possible detrimental effects of nutrient limitation during in vitro culture, the AAR has not been investigated in embryonic stem cells (ESC). AAR activation caused the expected increase in transcription factors that mediate specific AAR pathways, as well as the induction of asparagine synthetase, a terminal AAR target gene. Neither AAR activation nor stable knockdown of activating transcription factor (Atf) 4, a transcriptional mediator of the AAR, adversely affected ESC self-renewal or pluripotency. Low-level induction of the AAR over a 12-day period of embryoid body differentiation did alter lineage specification such that the primitive endodermal, visceral endodermal, and endodermal lineages were favored, whereas mesodermal and certain ectodermal lineages were suppressed. Knockdown of Atf4 further enhanced the AAR-induced increase in endodermal formation, suggesting that this phenomenon is mediated by an Atf4-independent mechanism. Collectively, the results indicate that, during differentiation of mouse embryoid bodies in culture, the availability of nutrients, such as amino acids, can influence the formation of specific cell lineages.
Sex-specific transcriptional responses of the zebrafish (Danio rerio) brain selenoproteome to acute sodium selenite supplementation
Authors: Benner Maia J. , Settles Matt L. , Murdoch Gordon K. , Hardy Ronald W. , Robison Barrie D.
Published: June 2013

The potential benefits of selenium (Se) supplementation are currently under investigation for prevention of certain cancers and treatment of neurological disorders. However, little is known concerning the response of the brain to increased dietary Se under conditions of Se sufficiency, despite the majority of Se supplementation trials occurring in healthy, Se sufficient subjects. We evaluated the transcriptional response of Se-dependent genes, selenoproteins and the genes necessary for their synthesis (the selenoproteome), in the zebrafish ( Danio rerio) brain to supplementation with nutritionally relevant levels of dietary Se (sodium selenite) during conditions of assumed Se sufficiency. We first used a microarray approach to analyze the response of the brain selenoproteome to dietary Se supplementation for 14 days and then assessed the immediacy and time-scale transcriptional response of the brain selenoproteome to 1, 7, and 14 days of Se supplementation by quantitative real-time PCR (qRT-PCR). The microarray approach did not indicate large-scale influences of Se on the brain transcriptome as a whole or the selenoproteome specifically; only one nonselenoproteome gene (si:ch73-44m9.2) was significantly differentially expressed. Our qRT-PCR results, however, indicate that increases of dietary Se cause small, but significant transcriptional changes within the brain selenoproteome, even after only 1 day of supplementation. These responses were dynamic over a short period of supplementation in a manner highly dependent on sex and the duration of Se supplementation. In nutritional intervention studies, it may be necessary to utilize methods such as qRT-PCR, which allow larger sample sizes, for detecting subtle transcriptional changes in the brain.
Predictors of Gait Speeds and the Relationship of Gait Speeds to Falls in Men and Women with Parkinson Disease
Authors: Nemanich Samuel T. , Duncan Ryan P. , Dibble Leland E. , Cavanaugh James T. , Ellis Terry D. , Ford Matthew P. , Foreman Kenneth B. , Earhart Gammon M.
Published: June 2013

Gait difficulties and falls are commonly reported in people with Parkinson disease (PD). Reduction in gait speed is a major characteristic of Parkinsonian gait, yet little is known about its underlying determinants, its ability to reflect an internal reservation about walking, or its relationship to falls. To study these issues, we selected age, disease severity, and nonmotor factors (i.e., depression, quality of life, balance confidence, and exercise beliefs and attitudes) to predict self-selected (SELF), fast-as-possible (FAST), and the difference (DIFF) between these walking speeds in 78 individuals with PD. We also examined gender differences in gait speeds and evaluated how gait speeds were related to a retrospective fall report. Age, disease severity, and balance confidence were strong predictors of SELF, FAST, and, to a lesser extent, DIFF. All three parameters were strongly associated with falling. DIFF was significantly greater in men compared to women and was significantly associated with male but not female fallers. The results supported the clinical utility of using a suite of gait speed parameters to provide insight into the gait difficulties and differentiating between fallers in people with PD.
Physical Properties of Nanostructured CdO Films from Alkaline Baths Containing Saccharin as Additive
Authors: Şahin Bünyamin
Published: June 2013

Nanostructured cadmium oxide (CdO) films were fabricated on glass substrates from alkaline baths containing saccharin as an additive by a successive ionic layer adsorption and reaction (SILAR) method. The effects of saccharin concentration in the bath on the structural, morphological, and optical properties were studied by means of scanning electron microscopy (SEM), X‐ray diffraction (XRD), photoluminescence, and Raman spectroscopy. The analyses showed that the surface morphologies, XRD peak intensities, Raman spectroscopy, and photoluminescence properties of CdO films changed with saccharin concentration. From the results, it can be said that morphological characteristic and optical properties of the films could be calibrated by adding various saccharin percentages in the growth bath.
Design Concept of Advanced Sodium-Cooled Fast Reactor and Related R&D in Korea
Authors: Kim Yeong-il , Lee Yong Bum , Lee Chan Bock , Chang Jinwook , Choi Chiwoong
Published: June 2013

Korea imports about 97% of its energy resources due to a lack of available energy resources. In this status, the role of nuclear power in electricity generation is expected to become more important in future years. In particular, a fast reactor system is one of the most promising reactor types for electricity generation, because it can utilize efficiently uranium resources and reduce radioactive waste. Acknowledging the importance of a fast reactor in a future energy policy, the long-term advanced SFR development plan was authorized by KAEC in 2008 and updated in 2011 which will be carried out toward the construction of an advanced SFR prototype plant by 2028. Based upon the experiences gained during the development of the conceptual designs for KALIMER, KAERI recently developed advanced sodium-cooled fast reactor (SFR) design concepts of TRU burner that can better meet the generation IV technology goals. The current status of nuclear power and SFR design technology development program in Korea will be discussed. The developments of design concepts including core, fuel, fluid system, mechanical structure, and safety evaluation have been performed. In addition, the advanced SFR technologies necessary for its commercialization and the basic key technologies have been developed including a large-scale sodium thermal-hydraulic test facility, super-critical Brayton cycle system, under-sodium viewing techniques, metal fuel development, and developments of codes, and validations are described as R&D activities.
Formation of Humic Substances in Weathered MSWI Bottom Ash
Authors: Zhang Haixia , Shimaoka Takayuki
Published: June 2013

The study aimed at evaluating the humic substances (HSs) content from municipal solid waste incinerator (MSWI) bottom ash and its variation with time and the effect of temperature on HSs formation. The process suggested by IHSS was applied to extract HSs from two different bottom ash samples, and the extracted efficiency with NaOH and Na4P2O7 was compared. MSWI bottom ash samples were incubated at 37∘C and 50∘C for 1 year. HSs and nonhumic substances were extracted from the bottom ash sample with different incubated period by 0.1 M NaOH/Na4P2O7. Results show that the rate of humic acid formation increased originally with incubation time, reached a maximum at 12th week under 37∘C and at 18th week under 50∘C, and then decreased with time. More humic acid in MSWI bottom ash was formed under 50∘C incubated condition compared with that incubated under 37∘C. Also, the elemental compositions of HSs extracted from bottom ash are reported.
Stability of Matrix Polytopes with a Dominant Vertex and Implications for System Dynamics
Authors: Pastravanu Octavian , Matcovschi Mihaela-Hanako
Published: June 2013

The paper considers the class of matrix polytopes with a dominant vertex and the class of uncertain dynamical systems defined in discrete time and continuous time, respectively, by such polytopes. We analyze the standard concept of stability in the sense of Schur—abbreviated as SS (resp., Hurwitz—abbreviated as HS), and we develop a general framework for the investigation of the diagonal stability relative to an arbitrary Hölderp-norm,1≤p≤∞, abbreviated asSDSp(resp.,HDSp). Our framework incorporates, as the particular case withp=2, the known condition of quadratic stability satisfied by a diagonal positive-definite matrix, i.e.SDS2(resp.,HDS2) means that the standard inequality of Stein (resp., Lyapunov) associated with all matrices of the polytope has a common diagonal solution. For the considered class of matrix polytopes, we prove the equivalence between SS andSDSp(resp., HS andHDSp),1≤p≤∞(fact which is not true for matrix polytopes with arbitrary structures). We show that the dominant vertex provides all the information needed for testing these stability properties and for computing the corresponding robustness indices. From the dynamical point of view, if an uncertain system is defined by a polytope with a dominant vertex, then the standard asymptotic stability ensures supplementary properties for the state-space trajectories, which refer to special types of Lyapunov functions and contractive invariant sets (characterized through vectorp-norms weighted by diagonal positive-definite matrices). The applicability of the main results is illustrated by two numerical examples that cover both discrete- and continuous-time cases for the class of uncertain dynamics studied in our paper.
On Stress-Strength Reliability with a Time-Dependent Strength
Authors: Eryilmaz Serkan
Published: June 2013

The study of stress-strength reliability in a time-dependent context needs to model at least one of the stress or strength quantities as dynamic. We study the stress-strength reliability for the case in which the strength of the system is decreasing in time and the stress remains fixed over time; that is, the strength of the system is modeled as a stochastic process and the stress is considered to be a usual random variable. We present stochastic ordering results among the lifetimes of the systems which have the same strength but are subjected to different stresses. Multicomponent form of the aforementioned stress-strength interference is also considered. We illustrate the results for the special case when the strength is modeled by a Weibull process.
A Human/Murine Chimeric Fab Antibody Neutralizes Anthrax Lethal ToxinIn Vitro
Authors: Ding Guipeng , Chen Ximin , Zhu Jin , Duesbery Nicholas S. , Cheng Xunjia , Cao Brian
Published: June 2013

Human anthrax infection caused by exposure toBacillus anthraciscannot always be treated by antibiotics. This is mostly because of the effect of the remaining anthrax toxin in the body. Lethal factor (LF) is a component of lethal toxin (LeTx), which is the major virulence of anthrax toxin. A murine IgG monoclonal antibody (mAb) against LF with blocking activity (coded LF8) was produced in a previous study. In this report, a human/murine chimeric Fab mAb (coded LF8-Fab) was developed from LF8 by inserting murine variable regions into human constant regions using antibody engineering to reduce the incompatibility of the murine antibody for human use. The LF8-Fab expressed inEscherichia colicould specifically identify LF with an affinity of3.46×107 L/mol and could neutralize LeTx with an EC50of 85 μg/mL. Even after LeTx challenge at various time points, the LF8-Fab demonstrated protection of J774A.1 cellsin vitro. The results suggest that the LF8-Fab might be further characterized and potentially be used for clinical applications against anthrax infection.
Dietary Flavonoids as Therapeutics for Preterm Birth: Luteolin and Kaempferol Suppress Inflammation in Human Gestational TissuesIn Vitro
Authors: Wall Courtney , Lim Ratana , Poljak Marin , Lappas Martha
Published: June 2013

Infection/inflammation is commonly associated with preterm birth (PTB), initiating uterine contractions and rupture of fetal membranes. Proinflammatory cytokines induce matrix metalloproteinases (MMPs) that degrade the extracellular matrix (ECM) and prostaglandins which initiate uterine contractions. Nuclear factor-κB (NF-κB) and activator-protein- (AP-)1 have key roles in the formation of these prolabour mediators. In nongestational tissues, dietary flavonoids such as luteolin and kaempferol inhibit NF-κB, AP-1, and their downstream targets. The aim of this study was to determine if luteolin and kaempferol reduce infection-induced prolabour mediators in human gestational tissues. Fetal membranes were incubated with LPS, and primary amnion cells and myometrial cells were incubated with IL-1βin the absence or presence of luteolin or kaempferol. Luteolin and kaempferol significantly reduced LPS-induced secretion of proinflammatory cytokines (IL-6 and IL-8) and prostaglandins (PGE2and PGF2α) in fetal membranes, IL-1β-induced COX-2 gene expression and prostaglandin production in myometrium, and IL-1β-induced MMP-9 activity in amnion and myometrial cells. Luteolin and kaempferol decreased IL-1β-induced NF-κB p65 DNA binding activity and nuclear c-Jun expression. In conclusion, luteolin and kaempferol inhibit prolabour mediators in human gestational tissues. Given the central role of inflammation in provoking preterm labour, phytophenols may be a therapeutic approach to reduce the incidence of PTB.
Impact of Tropical Storm Bopha on the Intensity Change of Super Typhoon Saomai in the 2006 Typhoon Season
Authors: Xu Hongxiong , Zhang Xuejin , Xu Xiangde
Published: June 2013

Super Typhoon Saomai (2006, 08W), which caused historical disaster in the landfall region, is the most powerful typhoon ever making landfall in Mainland China since 1949. The impact of Tropical Storm Bopha (2006, 10W) on Saomai is regarded as a binary tropical cyclone (TC) interaction. In order to quantify the influence of Bopha on the intensity of Saomai, a set of numerical experiments are performed by artificially modifying the intensity of Bopha in its initial conditions. It is shown that changing the intensity of Bopha has significant effects on simulating Saomai’s intensities, structures, and tracks. We find that moisture transport is a pivotal process of binary TC interaction. It is interesting that there are opposite effects by Bopha at different development stages of Saomai. The existence of Bopha and increasing its intensity would weaken Saomai at its intensifying stage while intensifying Saomai at its weakening stage. A possible explanation of these effects is the direction change of moisture transport from/to Saomai at its intensifying/weakening stages through the channel. It may suggest a significant relevance for operational intensity forecasts under active binary TC interaction.
Bioactive Surface Modification of Hydroxyapatite
Authors: Abe Yasuhiko , Okazaki Yohei , Hiasa Kyou , Yasuda Keisuke , Nogami Keisuke , Mizumachi Wataru , Hirata Isao
Published: June 2013

The purpose of this study was to establish an acid-etching procedure for altering the Ca/P ratio of the nanostructured surface of hydroxyapatite (HAP) by using surface chemical and morphological analyses (XPS, XRD, SEM, surface roughness, and wettability) and to evaluate thein vitroresponse of osteoblast-like cells (MC3T3-E1 cells) to the modified surfaces. This study utilized HAP and HAP treated with 10%, 20%, 30%, 40%, 50%, or 60% phosphoric acid solution for 10 minutes at 25°C, followed by rinsing 3 times with ultrapure water. The 30% phosphoric acid etching process that provided a Ca/P ratio of 1.50, without destruction of the grain boundary of HAP, was selected as a surface-modification procedure. Additionally, HAP treated by the 30% phosphoric acid etching process was stored under dry conditions at 25°C for 12 hours, and the Ca/P ratio approximated to 1.00 accidentally. The initial adhesion, proliferation, and differentiation (alkaline phosphatase (ALP) activity and relative mRNA level for ALP) of MC3T3-E1 cells on the modified surfaces were significantly promoted (P<0.05and 0.01). These findings show that the 30% phosphoric acid etching process for the nanostructured HAP surface can alter the Ca/P ratio effectively and may accelerate the initial adhesion, proliferation, and differentiation of MC3T3-E1 cells.
Neurovascular Unit in Chronic Pain
Authors: Radu Beatrice Mihaela , Bramanti Placido , Osculati Francesco , Flonta Maria-Luisa , Radu Mihai , Bertini Giuseppe , Fabene Paolo Francesco
Published: June 2013

Chronic pain is a debilitating condition with major socioeconomic impact, whose neurobiological basis is still not clear. An involvement of the neurovascular unit (NVU) has been recently proposed. In particular, the blood-brain barrier (BBB) and blood-spinal cord barrier (BSCB), two NVU key players, may be affected during the development of chronic pain; in particular, transient permeabilization of the barrier is suggested by several inflammatory- and nerve-injury-based pain models, and we argue that the clarification of molecular BBB/BSCB permeabilization events will shed new light in understanding chronic pain mechanisms. Possible biases in experiments supporting this theory and its translational potentials are discussed. Moving beyond an exclusive focus on the role of the endothelium, we propose that our understanding of the mechanisms subserving chronic pain will benefit from the extension of research efforts to the NVU as a whole. In this view, the available evidence on the interaction between analgesic drugs and the NVU is here reviewed. Chronic pain comorbidities, such as neuroinflammatory and neurodegenerative diseases, are also discussed in view of NVU changes, together with innovative pharmacological solutions targeting NVU components in chronic pain treatment.
Design and Implementation of a Control Strategy for Microgrid Containing Renewable Energy Generations and Electric Vehicles
Authors: Xia Mingchao , He Xuanhu , Zhang Xiaoqing
Published: June 2013

Large amount of such renewable energy generations as wind/photovoltaic generations directly connected to grid acting as distributed generations will cause control, protection, security, and safety problems. Microgrid, which has advantages in usage and control of distributed generations, is a promising approach to coordinate the conflict between distributed generations and the grid. Regarded as mobile power storages, batteries of electric vehicles can depress the fluctuation of power through the point of common coupling of microgrid. This paper presents a control strategy for microgrid containing renewable energy generations and electric vehicles. The control strategy uses current control for renewable energy generations under parallel-to-grid mode, and uses master-slave control under islanding mode. Simulations and laboratory experiments prove that the control strategy works well for microgrid containing renewable energy generations and electric vehicles and provides maximum power output of renewable energy and a stable and sustainable running under islanding mode.
Vibrations of a Slightly Curved Microbeam Resting on an Elastic Foundation with Nonideal Boundary Conditions
Authors: Sarı Gözde , Pakdemirli Mehmet
Published: June 2013

An investigation into the dynamic behavior of a slightly curved resonant microbeam having nonideal boundary conditions is presented. The model accounts for midplane stretching, an applied axial load, and a small AC harmonic force. The ends of the curved microbeam are on immovable simple supports and the microbeam is resting on a nonlinear elastic foundation. The forced vibration response of curved microbeam due to the small AC load is obtained analytically by means of direct application of the method of multiple scales (a perturbation method). The effects of the nonlinear elastic foundation as well as the effect of curvature on the vibrations of the microbeam are examined. It is found that the effect of curvature is of softening type. For sufficiently high values of the coefficients, the elastic foundation and the axial load may suppress the softening behavior resulting in hardening behavior of the nonlinearity. The frequencies and mode shapes obtained are compared with the ideal boundary conditions case and the differences between them are contrasted on frequency-response curves. The frequency response and nonlinear frequency curves obtained may provide a reference for the choice of reasonable resonant conditions, design, and industrial applications of such systems. Results may be beneficial for future experimental and theoretical works on MEMS.
Improving Anaerobic Digestion of Wheat Straw by Plasma-Assisted Pretreatment
Authors: Heiske Stefan , Schultz-Jensen Nadja , Leipold Frank , Schmidt Jens Ejbye
Published: June 2013

Plasma-assisted pretreatment (PAP) of lignocellulosic biomass has been shown to be an efficient method to decompose lignin and consequently facilitate microbial access to cellulose and hemicellulose. In the present study, PAP was tested for its suitability to enhance bioconversion of wheat straw to methane. In thermophilic batch experiments, methane yields of up to 366 mL/g volatile solids (VSs) were achieved, accounting for a yield increase of 45%. Common lignin-derived inhibitors like 5-hydroxymethylfurfural (5-HMF) and furfural were not detected after PAP, but toxicity test resulted in lower methane yields at higher substrate concentrations, indicating the presence of other unidentified inhibitors. However, in a continuous lab-scale biogas reactor experiment, stable codigestion of cattle manure with 20% PAP wheat straw was demonstrated, while no signs of adverse effects on the anaerobic digestion process were observed. After the introduction of the pretreated wheat straw to the reactor, volatile fatty acid concentrations remained low and stable, while gas production increased. In co-digestion, the PAP wheat straw was converted at an average yield of 343 mL CH4/gVS.
An Image Enhancement Method Using the Quantum-Behaved Particle Swarm Optimization with an Adaptive Strategy
Authors: Su Xiaoping , Fang Wei , Shen Qing , Hao Xiulan
Published: June 2013

Image enhancement techniques are very important to image processing, which are used to improve image quality or extract the fine details in degraded images. In this paper, two novel objective functions based on the normalized incomplete Beta transform function are proposed to evaluate the effectiveness of grayscale image enhancement and color image enhancement, respectively. Using these objective functions, the parameters of transform functions are estimated by the quantum-behaved particle swarm optimization (QPSO). We also propose an improved QPSO with an adaptive parameter control strategy. The QPSO and the AQPSO algorithms, along with genetic algorithm (GA) and particle swarm optimization (PSO), are tested on several benchmark grayscale and color images. The results show that the QPSO and AQPSO perform better than GA and PSO for the enhancement of these images, and the AQPSO has some advantages over QPSO due to its adaptive parameter control strategy.
Preparation of Fe-DopedTiO2Nanotubes and Their Photocatalytic Activities under Visible Light
Authors: Teng Honghui , Xu Shukun , Sun Dandan , Zhang Ying
Published: June 2013

Fe-doped TiO2nanotubes (Fe-TNTs) have been prepared by ultrasonic-assisted hydrothermal method. The structure and composition of the as-prepared TiO2nanotubes were characterized by transmission electron microscopy, X-ray diffraction, and UV-Visible absorption spectroscopy. Their photocatalytic activities were evaluated by the degradation of MO under visible light. The UV-visible absorption spectra of the Fe-TNT showed a red shift and an enhancement of the absorption in the visible region compared to the pure TNT. The Fe-TNTs were provided with good photocatalytic activities and photostability and under visible light irradiation, and the optimum molar ratio of Ti : Fe was found to be 100 : 1 in our experiments.
C-RAF Mutations Confer Resistance to RAF Inhibitors
Authors: Antony Rajee , Emery Caroline M. , Sawyer Allison M. , Garraway Levi A.
Published: June 2013

Melanomas that contain B-RAFV600E mutations respond transiently to RAF and MEK inhibitors; however, resistance to these agents remains a formidable challenge. Although B- or C-RAF dysregulation represents prominent resistance mechanisms, resistance-associated point mutations in RAF oncoproteins are surprisingly rare. To gain insights herein, we conducted random mutagenesis screens to identify B- or C-RAF mutations that confer resistance to RAF inhibitors. Whereas bona fide B-RAFV600E resistance alleles were rarely observed, we identified multiple C-RAF mutations that produced biochemical and pharmacologic resistance. Potent C-RAF resistance alleles localized to a 14-3-3 consensus binding site or a separate site within the P loop. These mutations elicited paradoxical upregulation of RAF kinase activity in a dimerization-dependent manner following exposure to RAF inhibitors. Knowledge of resistance-associated C-RAF mutations may enhance biochemical understanding of RAF-dependent signaling, anticipate clinical resistance to novel RAF inhibitors, and guide the design of “next-generation” inhibitors for deployment in RAF- or RAS-driven malignancies. Cancer Res; 73(15); 4840–51. ©2013 AACR.
Potent Immunomodulatory Effects of the Trifunctional Antibody Catumaxomab
Authors: Goéré Diane , Flament Caroline , Rusakiewicz Sylvie , Poirier-Colame Vichnou , Kepp Oliver , Martins Isabelle , Pesquet Julien , Eggermont Alexander , Elias Dominique , Chaput Nathalie , Zitvogel Laurence
Published: June 2013

Catumaxomab (CatmAb), a trifunctional bispecific antibody directed against the epithelial cell adhesion molecule (EpCAM) and the T-cell antigen CD3, is approved as intraperitoneal therapy for the treatment of malignant ascites in patients with EpCAM-positive carcinomas. The immunomonitoring results of a phase II/III study using CatmAb revealed a tumoricidal effect associated with reduced VEGF levels, CD69-expressing T cells, and the release of T-helper cell (TH)-1 cytokines. We comprehensively dissected the immunomodulatory effects of the CatmAb on the major subsets of malignant ascites-infiltrating leukocytes and the molecular fingerprint of tumor cell death. Herein we show that in the presence of EpCAM-positive tumor targets, CatmAb markedly enhanced T-cell activation [CD69, CD107A (LAMP1), HLA-DR and PD-1(PDCD1) expression] and stimulated inflammatory CD4+ TH1 and CD8+ TH1 to release IFN-γ but failed to trigger TH17 cells. Engagement of CD16-expressing cells caused upregulation of TRAIL (TNFSF10) and costimulatory CD40 and CD80 molecules. CatmAb promoted tumor cell death associated with ATP release and strongly synergized with oxaliplatin for the exposure of the three hallmarks of immunogenic cell death (calreticulin, HMGB1, and ATP). These findings warrant validation as potential biomarkers of efficacy of CatmAb. Cancer Res; 73(15); 4663–73. ©2013 AACR.
Clinical and Morphological Characteristics of Sporadic Genetically Determined Pancreatitis as Compared to Idiopathic Pancreatitis: Higher Risk of Pancreatic Cancer in CFTR Variants
Authors: Hamoir Coralie , Pepermans Xavier , Piessevaux Hubert , Jouret-Mourin Anne , Weynand Birgit , Habyalimana Jean-Baptiste , Leal Teresinha , Geubel André , Gigot Jean-François , Deprez Pierre H.
Published: June 2013

Background/Aims: Idiopathic pancreatitis is considered to be a multigenic and multifactorial disease. Genetically determined pancreatitis is associated with mutations in the PRSS1,SPINK1 and CFTR genes. This study aimed at examining the clinical and morphological characteristics of patients diagnosed with genetically determined sporadic pancreatitis. Methods: Inclusion criteria were the presence of PRSS1,CFTR or SPINK1 gene mutations in patients with idiopathic recurrent or chronic pancreatitis. Patients with hereditary pancreatitis were excluded. Age- and sex-matched patients with idiopathic pancreatitis and negative genetic testing served as controls (n = 68). Results: Genetic testing was performed in 351 probands referred to our centre since 1999. Sixty-one patients (17.4%) carried at least 1 detected mutation in 1 of the 3 tested genes (34 CFTR, 10 PRSS1 and 13 SPINK1 mutations), and 4 patients showed a combination of mutations. Follow-up has been currently extended to a median of 5 years (range 1-40). Similar clinical features were noted in the case and matched groups except for an earlier age of onset of pancreatic symptoms and a higher incidence of pancreatic cancer in the case group and in patients with CFTR mutations compared to the control group (p < 0.05). The standardized incidence ratio, the ratio of observed to expected pancreatic cancers, averaged 26.5 (95% confidence interval 8.6-61.9). All pancreatic cancer patients were smokers. Conclusion: Clinical parameters of patients with sporadic idiopathic pancreatitis and gene mutations are similar to those of age- and sex-matched patients without gene mutations, except for the age of pancreatic disease onset. A significantly higher occurrence of pancreas cancer was observed in the case group, particularly in those patients carrying CFTR mutations. We therefore suggest to include patients with CFTR variants presenting with risk factors in a screening and surveillance programme and to strongly advise them to stop smoking.
Chronic Active Epstein-Barr Virus Infection-Associated Hydroa Vacciniforme-Like Eruption and Behçet's-Like Orogenital Ulcers
Authors: Park B.M. , Ahn J.-S. , Lee J.B. , Won Y.H. , Yun S.J.
Published: June 2013

The cutaneous manifestations of chronic active Epstein-Barr virus (EBV) infection can be diverse. Among them, hydroa vacciniforme-like eruption is one of the best-known features. Although rare, mucosal ulcers have been reported to be associated with EBV as a result of primary infection or immune suppression. We describe a 65-year-old female with recurrent necrotic papulovesicles on the face and both arms for 2 years. She also complained of recurrent oral and genital mucosal ulcers developing simultaneously with skin eruptions. They appeared periodically during the spring and summer and were triggered or aggravated by sun exposure. Skin biopsies from the face and genitalia showed identical findings with dense lymphocytic infiltrations. In addition, in situ hybridization revealed EBV-positive lymphoid cells in both specimens. To our knowledge, this is the first case of serologically and pathologically proven chronic active EBV infection presenting hydroa vacciniforme-like eruption and orogenital ulcers at the same time in one patient.
Post-Stroke Apathy: An Exploratory Longitudinal Study
Authors: Caeiro Lara , Ferro José M. , Pinho e Melo Teresa , Canhão Patrícia , Figueira M. Luísa
Published: June 2013

Introduction: Post-stroke apathy is a disturbance of motivation evidenced by low initiative, difficulties in starting, sustaining or finishing any goal-directed activity, low self-activation or self-initiated behavior and emotional indifference. Apathy is a common behavioral disturbance in stroke survivors. We aimed to analyze the relationship between post-stroke apathy at 1 year after stroke and (1) apathy in acute phase; (2) demographic, pre-stroke predisposing conditions (previous mild cognitive impairment, alcohol abuse, mood/anxiety disorder) and clinical features (stroke type and location, neurological symptoms); (3) post-stroke depression and post-stroke cognitive impairment, and (4) post-stroke functional outcome, quality of life and the perception of health. Methods: Consecutive stroke (infarct/intracerebral hemorrhage) patients without aphasia or consciousness disturbances were included in the acute phase of stroke and assessed at 1 year after stroke. We assessed apathy with the clinically rated version of the Apathy Evaluation Scale. We also assessed post-stroke depression (Montgomery Asberg Depression Rating Scale) and post-stroke cognitive impairment (attention, mental flexibility, verbal, motor and graphomotor initiative, and non-verbal and verbal abstract reasoning, and Mini-Mental State Examination), functional outcome (Barthel Index), quality of life and perception of health (EuroQol). Data were analyzed using bivariate associations (χ2 and t test) and stepwise multivariate analysis. Results: We included 76 stroke patients [32.9% women, mean age 62.9 years (SD = 10.9) and a mean of 6.9 (SD = 4.3) years of education]. Apathy was present in 17 patients in the acute phase and in 18 (23.7%) patients at 1 year after stroke. At 1 year after stroke, 41% of the acute apathetic patients remained apathetic. Sixty-one percent of new cases of post-stroke apathy were detected. Post-stroke apathy was associated only with previous cognitive impairment, apathy in acute stroke, post-stroke cognitive impairment, verbal abstract reasoning and with worse Barthel Index scale scores. In the multivariate logistic regression model, verbal abstract reasoning (odds ratio, OR = 7.03) and apathy in acute stroke (OR = 3.8) were identified as independent factors for post-stroke apathy at 1 year. Apathetic patients did not report worse quality of life or health. Conclusion: Apathy in acute stroke phase was a reliable indicator of post-stroke apathy. Apathy should be assessed in both phases. Verbal abstract reasoning impairment was also an independent factor for post-stroke apathy impairing patients' ability to reason about goal-directed activity. Even though apathetic patients had worse post-stroke functional outcome, they did not report losing quality of life or having worse health.
Minimally Invasive Surgery for Patients with Bulky Bladder Stones and Large Benign Prostatic Hyperplasia Simultaneously: A Novel Design
Authors: Zhao JunJie , Shi Lei , Gao ZhenLi , Liu QingZuo , Wang Ke , Zhang Peng
Published: June 2013

Objective: To determine the efficacy and safety of a novel minimally invasive design for treating bulky vesical calculi and large benign prostatic hyperplasia (BPH) simultaneously. Methods: 76 patients with large bladder stones (>4 cm) and large BPH (≥50 cm3) were treated from August 2008 to January 2011. 38 patients (group 1) underwent transurethral cystolithotripsy followed by transurethral resection of the prostate (TURP), 38 patients (group 2) received percutaneous cystolithotripsy within a laparoscopic entrapment bag and TURP by two surgeons simultaneously. 72 patients were followed up for 1 year. Patient demographics, perioperative parameters and follow-up data were compared. Results: Patient baseline characteristics were comparable in the two groups. In group 1, 3 patients converted to open surgery and received blood transfusion, 4 patients had postoperative fever, 2 had residual stones and 1 developed urethral stricture postoperatively. In group 2, the mean total operative and the operative times for stone management were 71.6 and 30.1 min, respectively, the mean hemoglobin decrease was 0.80 g/dl, no patients received blood transfusion and no complications occurred, signiﬁcantly superior to group 1. Conclusions: Percutaneous cystolithotripsy using a laparoscopic entrapment bag associated with TURP by two surgeons simultaneously is a highly effective, safe and minimally invasive method for managing large vesical calculi and large BPH.
Impact of Humans on Long-Distance Communication Behaviour of Eastern Chimpanzees (Pan troglodytes schweinfurthii) in the Northern Democratic Republic of the Congo
Authors: Hicks Thurston C. , Roessingh Peter , Menken Steph B.J.
Published: June 2013

We systematically recorded all long-distance chimpanzee vocalizations and tree drums over a 26-month study period in 13 forest regions in the Democratic Republic of the Congo. We found that the frequency of chimpanzee vocalizations and tree drums was considerably higher in the remote Gangu Forest than in other forest regions closer to human settlements and roads. We present evidence indicating that chimpanzees may reduce their levels of vocalizations in areas characterized by high levels of human hunting. The chimpanzees appear to have the behavioural flexibility necessary to modify their behaviour in areas where humans are a major threat. We discuss the possible consequences of this reduction in vocalization rate on the social system of the chimpanzees.
Association of Oesophageal Varices and Splanchnic Vein Thromboses in Patients with JAK2-Positive Myeloproliferative Neoplasms: Presentation of Two Cases and Data from a Retrospective Analysis
Authors: Link Cornelia S. , Platzbecker Uwe , Kroschinsky Frank , Pannach Sven , Thiede Christian , Platzek Ivan , Ehninger Gerhard , Schuler Markus K.
Published: June 2013

Background: Oesophageal varices and gastrointestinal bleeding are common complications of liver cirrhosis. More rarely, oesophageal varices occur in patients with non-cirrhotic portal hypertension that results from thromboses of portal or splanchnic veins. Case Report: We describe 2 young men who initially presented with varices as a result of portal vein thromboses. In the clinical follow-up, both were tested positive for a JAK2 mutation and consequently diagnosed with myeloproliferative neoplasms (MPNs). In an attempt to characterise the frequency of gastrointestinal complications in patients with JAK2-positive MPNs, we retrospectively analysed all known affected patients from our clinic for the diagnosis of portal vein thromboses and oesophageal varices. Strikingly, 48% of those who had received an oesophagogastroduodenoscopy had detectable oesophageal or gastric varices, and 82% of those suffered from portal or splanchnic vein thromboses. Conclusion: While the association between JAK2, myeloproliferative disease and thrombotic events is well established, patients with idiopathic oesophageal varices are not regularly tested for JAK2 mutations. However, the occurrence of oesophageal varices may be the first presenting symptom of a MPN with a JAK2 mutation, and affected patients may profit from a close haematological monitoring to assure the early detection of developing MPN.