bluuebunny/crossref_metadata_2025_split huggingface dataset:
Poly(butylene succinate)/layered double hydroxide bionanocomposites: Relationships between chemical structure of LDH anion, delamination strategy, and final properties
Authors: Sisti Laura , Totaro Grazia , Fiorini Maurizio , Celli Annamaria , Coelho Christian , Hennous Mohammed , Verney Vincent , Leroux Fabrice 
Published: May 2013

ABSTRACTA series of poly(butylene succinate) (PBS) containing organo‐modified layered double hydroxide (LDH) are prepared by melt compounding and by in situ polymerization of succinic ester and 1,4‐butanediol. Various LDHs intercalated with renewable organic anions are used. More specifically, lauryl sulfate, stearate, succinate, adipate, sebacate, citrate, and ricinoleate ions are used as LDHs organo‐modifiers. The thermal, rheological, and dynamic mechanical properties of the samples are investigated. The results reveal a general mechanical reinforcement imparted by the clays. Significant changes are observed for the in situ polymerized nanocomposites, especially for LDH stearate which improves the properties of PBS nanostructure, whereas very few differences are observed for the other samples. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1931–1940, 2013
Highly scalable nanoparticle–polymer composite fiber via wet spinning
Authors: Stone Roland , Hipp Stephen , Barden Joel , Brown Phillip J. , Mefford O. Thompson 
Published: May 2013

ABSTRACTMagnetic nanoparticles have continued to gather the interest of researchers due to the unique physical properties of materials found at this size scale. Herein, the production of composite magnetic fibers composed of iron oxide nanoparticles suspended in alginate is described. These materials were produced via wet spinning of a sodium alginate solution into a bath of an aqueous solution of calcium chloride. The magnetic fibers were found to have similar mechanical properties to normal alginate fibers, and exhibited superparamagnetic behavior when subjected to an external DC magnetic field. In addition, the particle loaded fibers demonstrated the potential to produce significant amounts of heat when exposed to an AC magnetic field, suggesting these new materials could be applicable to a variety of applications including magnetic hyperthermia. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1975–1980, 2013
Stimulation of Fibrotic Processes by the Infrapatellar Fat Pad in Cultured Synoviocytes From Patients With Osteoarthritis: A Possible Role for Prostaglandin F2α
Authors: Bastiaansen‐Jenniskens Yvonne M. , Wei Wu , Feijt Carola , Waarsing Jan H. , Verhaar Jan A. N. , Zuurmond Anne‐Marie , Hanemaaijer Roeland , Stoop Reinout , van Osch Gerjo J. V. M. 
Published: May 2013

ObjectiveStiffening of the joint is a feature of knee osteoarthritis (OA) that can be caused by fibrosis of the synovium. The infrapatellar fat pad (IPFP) present in the knee joint produces immune‐modulatory and angiogenic factors. The goal of the present study was to investigate whether the IPFP can influence fibrotic processes in synovial fibroblasts, and to determine the role of transforming growth factor β (TGFβ) and prostaglandin F2α (PGF2α) in these processes.MethodsBatches of fat‐conditioned medium (FCM) were made by culturing pieces of IPFP obtained from the knees of 13 patients with OA. Human OA fibroblast‐like synoviocytes (FLS) (from passage 3) were cultured in FCM with or without inhibitors of TGFβ/activin receptor–like kinase 5 or PGF2α for 4 days. The FLS were analyzed for production of collagen and expression of the gene for procollagen‐lysine, 2‐oxoglutarate 5‐dioxygenase 2 (PLOD2; encoding lysyl hydroxylase 2b, an enzyme involved in collagen crosslinking) as well as the genes encoding α‐smooth muscle actin and type I collagen α1 chain. In parallel, proliferation and migration of the synoviocytes were analyzed.ResultsCollagen production and PLOD2 gene expression by the FLS were increased 1.8‐fold (P < 0.05) and 6.0‐fold (P < 0.01), respectively, in the presence of FCM, relative to control cultures without FCM. Moreover, the migration and proliferation of synoviocytes were stimulated by FCM. Collagen production was positively associated with PGF2α levels in the FCM (R = 0.89, P < 0.05), and inhibition of PGF2α levels reduced the extent of FCM‐induced collagen production and PLOD2 expression. Inhibition of TGFβ signaling had no effect on the profibrotic changes.ConclusionThese results indicate that the IPFP can contribute to the development of synovial fibrosis in the knee joint by increasing collagen production, PLOD2 expression, cell proliferation, and cell migration. In addition, whereas the findings showed that TGFβ is not involved, the more recently discovered profibrotic factor PGF2α appears to be partially involved in the regulation of profibrotic changes.
Osteoprotegerin Causes Apoptosis of Endothelial Progenitor Cells by Induction of Oxidative Stress
Authors: Kim Ji‐Young , Park Yune‐Jung , Kim Ki‐Jo , Choi Jin‐Jung , Kim Wan‐Uk , Cho Chul‐Soo 
Published: May 2013

ObjectiveElevated serum osteoprotegerin (OPG) levels represent an independent risk factor for atherosclerotic disease, although the underlying mechanism is not clear. The aim of this study was to investigate the association of serum OPG levels and circulating endothelial progenitor cell (EPC) numbers, and to explore the effect of OPG on EPC apoptosis and its underlying mechanisms.MethodsFlow cytometry was used to enumerate EPCs in the peripheral blood of 91 patients with systemic lupus erythematosus (SLE). Cultured EPCs, isolated from peripheral blood, were challenged with OPG, and apoptosis was evaluated by TUNEL staining. Expression of apoptosis‐related proteins was measured by real‐time quantitative polymerase chain reaction (qPCR) and Western blotting. Reactive oxygen species (ROS) were detected by flow cytometry, and the expression of NADPH oxidase (NOX) and MAP kinases (MAPK) was measured by qPCR and Western blotting.ResultsThe serum OPG level was independently associated with reduced numbers of EPCs in patients with SLE. In vitro treatment with OPG significantly induced apoptosis of EPCs; this effect was mediated by syndecan 4. OPG‐induced apoptosis was abolished by the ROS scavenger N‐acetylcysteine and the NOX inhibitor diphenyleniodonium. OPG increased ROS production through activation of NOX‐2 and NOX‐4 and triggered phosphorylation of ERK‐1/2 and p38 MAPK. Quenching of ROS by knockdown of NOX‐2 or NOX‐4 transcripts inhibited phosphorylation of ERK‐1/2 and p38 MAPK. Moreover, inhibitors of ERK‐1/2 and p38 MAPK decreased ROS production and subsequent EPC apoptosis, indicating a feed‐forward loop between NOX and MAPK to amplify ROS production related to apoptosis.ConclusionElevated OPG levels increase apoptosis of EPCs by induction of oxidative stress.
HLA–B27 Alters the Response to Tumor Necrosis Factor α and Promotes Osteoclastogenesis in Bone Marrow Monocytes From HLA–B27–Transgenic Rats
Authors: Layh‐Schmitt Gerlinde , Yang Eva Y. , Kwon Grace , Colbert Robert A. 
Published: May 2013

ObjectiveTo determine whether HLA–B27 expression alters the response of bone marrow monocytes from HLA–B27/human β2‐microglobulin–transgenic (B27‐Tg) rats to tumor necrosis factor α (TNFα) and, if so, whether this affects the cells involved in bone homeostasis.MethodsBone marrow monocytes were treated with RANKL or with TNFα to promote osteoclast formation. Osteoclasts were quantified by counting. Gene expression was measured using quantitative polymerase chain reaction analysis, and protein was detected by enzyme‐linked immunosorbent assay, immunoblotting, or immunofluorescence. Effects of endogenously produced cytokines on osteoclast formation were determined with neutralizing antibodies.ResultsTNFα treatment enhanced osteoclast formation 2.5‐fold in HLA–B27–expressing cells as compared to wild‐type or to HLA–B7/human β2‐microglobulin–expressing monocytes. TNFα induced ∼4‐fold up‐regulation of HLA–B27, which was associated with the accumulation of misfolded heavy chains, binding of the endoplasmic reticulum (ER) chaperone BiP, and activation of an ER stress response, which was not seen with HLA–B7. No differences were seen with RANKL‐induced osteoclastogenesis. Enhanced interleukin‐1α (IL‐1α) production from ER‐stressed bone marrow monocytes from B27‐Tg rats was found to be necessary and sufficient for enhanced osteoclast formation. However, bone marrow monocytes from B27‐Tg rats also produced more interferon‐β (IFNβ), which attenuated the effect of IL‐1α on osteoclast formation.ConclusionHLA–B27–induced ER stress alters the response of bone marrow monocytes from B27‐Tg rats to TNFα, which is associated with enhanced production of IL‐1α and IFNβ, cytokines that exhibit opposing effects on osteoclast formation. The altered response of cells expressing HLA–B27 to proinflammatory cytokines suggests that this class I major histocompatibility complex allele may contribute to the pathogenesis of spondyloarthritis and its unique phenotype through downstream effects involving alterations in bone homeostasis.
Ribosomally Synthesized and Post‐Translationally Modified Peptide Natural Products: New Insights into the Role of Leader and Core Peptides during Biosynthesis
Authors: Yang Xiao , van der Donk Wilfred A. 
Published: May 2013

AbstractRibosomally synthesized and post‐translationally modified peptides (RiPPs) are a major class of natural products with a high degree of structural diversity and a wide variety of bioactivities. Understanding the biosynthetic machinery of these RiPPs will benefit the discovery and development of new molecules with potential pharmaceutical applications. In this Concept article, we discuss the features of the biosynthetic pathways to different RiPP classes, and propose mechanisms regarding recognition of the precursor peptide by the post‐translational modification enzymes. We propose that the leader peptides function as allosteric regulators that bind the active form of the biosynthetic enzymes in a conformational selection process. We also speculate how enzymes that generate polycyclic products of defined topologies may have been selected for during evolution.
Color reproduction of authenticable luminescent backlit transmissive color images
Authors: Andres Julien , Hersch Roger D. 
Published: May 2013

AbstractWe propose a method for creating authenticable color images under UV excitation backlight by printing an invisible luminescent white emissive ink layer on the verso side of a transmissive substrate and a classical cmy image on the recto side of the substrate. In order to obtain a backlit image whose colors are as close as possible to the original image colors, we map the input image sRGB color gamut into the gamut formed by the emissive white source attenuated by the classical ink halftones. The relationship between surface coverages of the classical cmy ink halftones and the resulting backlit colors is obtained by accounting for the transmission of the emissive white through the paper substrate and through the classical cmy ink halftones. The transmittance of the classical ink halftones is modeled by a new halftone absorbance prediction model. The lightness range of the luminescent backlit color gamut is expanded by printing a black and white UV‐absorbing instance of the original color image in superposition with the luminescent white emissive layer and in registration with the cmy image printed on the recto side. Luminescent backlit color images provide a high anticounterfeiting security, as they combine a verso printed invisible luminescent ink layer, a verso printed black and white instance of the original image and a matching recto printed cmy instance of the original image. The resulting luminescent backlit image colors are close to the original image colors only when observed in transmission mode under UV light. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 331–340, 2014
Accelerating R‐based analytics on the cloud
Authors: Patel Ishan , Rau‐Chaplin Andrew , Varghese Blesson 
Published: May 2013

SummaryThis paper addresses how the benefits of cloud‐based infrastructure can be harnessed for analytical workloads. Often, the software handling analytical workloads is not developed by a professional programmer but on an ad hoc basis by analysts in high‐level programming environments such as R or MATLAB. The goal of this research is to allow Analysts to take an analytical job that executes on their personal workstations and with minimum effort execute it on cloud infrastructure and manage both the resources and the data required by the job. If this can be facilitated gracefully, then the Analyst benefits from on‐demand resources, low maintenance cost and scalability of computing resources, all of which are offered by the cloud. In this paper, a Platform for Parallel R‐based Analytics on the Cloud (P2RAC) that is placed between an Analyst and a cloud infrastructure is proposed and implemented. P2RAC offers a set of command‐line tools for managing the resources, such as instances and clusters, the data and the execution of the software on the Amazon Elastic Computing Cloud infrastructure. Experimental studies are pursued using two parallel problems and the results obtained confirm the feasibility of employing P2RAC for solving large‐scale analytical problems on the cloud.Copyright © 2013 John Wiley & Sons, Ltd.
PU text classification enhanced by term frequency–inverse document frequency‐improved weighting
Authors: Peng Tao , Liu Lu , Zuo Wanli 
Published: May 2013

SUMMARYTerm frequency–inverse document frequency (TF–IDF), one of the most popular feature (also called term or word) weighting methods used to describe documents in the vector space model and the applications related to text mining and information retrieval, can effectively reflect the importance of the term in the collection of documents, in which all documents play the same roles. But, TF–IDF does not take into account the difference of term IDF weighting if the documents play different roles in the collection of documents, such as positive and negative training set in text classification. In view of the aforementioned text, this paper presents a novel TF–IDF‐improved feature weighting approach, which reflects the importance of the term in the positive and the negative training examples, respectively. We also build a weighted voting classifier by iteratively applying the support vector machine algorithm and implement one‐class support vector machine and Positive Example Based Learning methods used for comparison. During classifying, an improved 1‐DNF algorithm, called 1‐DNFC, is also adopted, aiming at identifying more reliable negative documents from the unlabeled examples set. The experimental results show that the performance of term frequency inverse positive–negative document frequency‐based classifier outperforms that of TF–IDF‐based one, and the performance of weighted voting classifier also exceeds that of one‐class support vector machine‐based classifier and Positive Example Based Learning‐based classifier. Copyright © 2013 John Wiley & Sons, Ltd.
Impossible differential cryptanalysis on cipher E2
Authors: Wei Yuechuan , Yang Xiaoyuan , Li Chao 
Published: May 2013

SUMMARYE2, a block cipher, is an Advanced Encryption Standard candidate designed and submitted by Nippon Telegraph and Telephone Corporation. It employs a Feistel structure as global structure and two‐layer substitution–permutation network structure in round function. The conservative structure makes E2 immune to kinds of current cryptanalysis. Previously, there is no result of impossible differential attacks on E2 because it was once supposed to have no more than five‐round impossible differential characteristic. In this paper, we present a series of six‐round impossible differential characteristics of E2 with/without initial transformation (IT)/ final transformation (FT) functions. Based on these impossible differentials, the immunity of E2 against impossible differential cryptanalysis is evaluated. We perform a seven‐round attack on tweaked E2 (E2 without IT and FT ) with 128, 192, and 256 bits key and an eight‐round attack on tweaked E2 with 256 bits key. The seven‐round attack requires about 2120 chosen plaintexts and 2115.5 seven‐round encryptions; the eight‐round attack needs 2121 chosen plaintexts and less than 2214 eight‐round encryptions. We also discuss the seven‐round attack on E2 with IT or FT, and the result shows that the attack has the same complexities with the seven‐round attack on tweaked E2. Copyright © 2013 John Wiley & Sons, Ltd.
Plasma processing for carbon nanomaterials. Syntheses of nanostructures and their process control by numerical simulation of plasma
Authors: Suda Yoshiyuki , Takikawa Hirofumi , Tanoue Hideto 
Published: May 2013

AbstractPlasma is a useful tool to synthesize carbon nanomaterials, including diamonds, fullerenes, nanotubes, and graphenes. This review gives an overview of these carbon nanomaterials produced by thermal or nonthermal plasmas and of the authors' work related to plasma‐enhanced chemical vapor deposition of carbon nanotubes, along with an analysis and numerical simulation of CH4/H2 feedstock gas plasmas. The amount of carbon atoms in the grown carbon nanotubes and that calculated by simulation showed good agreement. © 2013 Wiley Periodicals, Inc. Electron Comm Jpn, 96(6): 1–8, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11504
Load and battery charge oriented flooding for broadcast streaming over ad hoc networks
Authors: Utsu Keisuke , Ishii Hiroshi 
Published: May 2013

AbstractThis paper considers cases where a speciﬁc number of nodes in an ad hoc network broadcast video and audio streams over the entire network, and proposes Load and Battery Charge Oriented Flooding (LBF), which reduces degradation in delivery quality, lowers energy consumption, and prevents nodes from being interrupted due to the complete discharge of their batteries. It also describes an evaluation of the proposed method through network simulation, and conﬁrms its eﬀectiveness. © 2013 Wiley Periodicals, Inc. Electron Comm Jpn, 96(6): 57–66, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11567
Estimation of the current peak value distribution of all lightning to the ground by electro‐geometric model
Authors: Sakata Tadashi , Yamamoto Kazuo , Sekioka Shozo , Yokoyama Shigeru 
Published: May 2013

AbstractWhen we examine the lightning frequency and the lightning shielding eﬀect of the electro‐geometric model (EGM), we need the current distribution of all lightning to the ground. The distribution of lightning current to structures is diﬀerent from this distribution, but it has been used in EGM conventionally. We assumed the lightning striking distance coeﬃcient related to the height of structures in order to obtain a result which corresponds to the observed frequency of lightning to structures, and estimated the current distribution of all lightning to the ground from data listed in the IEC 62305 series of EGM. The estimated distribution adjusted by the LLS detection eﬃciency agreed well with the distribution observed by LLS. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 184(3): 14–26, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22356
Position sensorless control of IPMSMs based on a novel flux model suitable for maximum torque control
Authors: Matsumoto Atsushi , Hasegawa Masaru , Matsui Keiju 
Published: May 2013

AbstractIn this paper, a novel position sensorless control method for interior permanent magnet synchronous motors (IPMSMs) that is based on a novel ﬂux model suitable for maximum torque control has been proposed. Maximum torque per ampere (MTPA) control is often utilized for driving IPMSMs with the maximum eﬃciency. In order to implement this control, generally, the accurate motor parameters are required. However, the inductance varies dramatically because of magnetic saturation, which has been one of the most important problems in recent years. Therefore, the conventional MTPA control method fails to achieve maximum eﬃciency for IPMSMs because of parameter mismatches. In this paper, ﬁrst, a novel ﬂux model has been proposed for realizing the position sensorless control of IPMSMs, which is insensitive to Lq. In addition, in this paper it is shown that the proposed ﬂux model can approximately estimate the maximum torque control (MTC) frame, which is a new coordinate aligned with the current vector for MTPA control. Next, in this paper, a precise estimation method for the MTC frame has been proposed. By this method, highly accurate maximum torque control can be achieved. A decoupling control algorithm based on the proposed model is also addressed in this paper. Finally, some experimental results demonstrate the feasibility and eﬀectiveness of the proposed method. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 184(3): 55–66, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22380
Security issues for mega penetration of photovoltaic power generation in future electric power systems. A case study of stability for power swing oscillation using the IEEJ WEST 10‐machine model
Authors: Okumoto Yoshiharu , Yorino Naoto , Sasaki Yutaka , Zoka Yoshifumi , Fujita Shoki , Yamanaka Toshihiro 
Published: May 2013

AbstractMega penetration of photovoltaic power generation (PV) will be introduced in future electric power systems, dealing with environmental problems such as global warming and energy exhaustion. The authors have pointed out that diﬃculties will arise in meeting the N‐1 security standard if increases in uncertainties cannot be avoided due to PV penetration. Thus, we have proposed a new concept of “robust power system security” together with several conditions to be satisﬁed in order to guarantee the N‐1 security standard under uncertainties. In this paper, (1) a model of uncertainties due to PV generation is proposed based on robust power system security; a method for proper parameter selection is also provided. Then, (2) the inﬂuence on the stability of the PV and load disconnection from the power system is studied through simulation using the model system; (3) the eﬀect of PV fault ride‐through (FRT) on stability is investigated along with dynamic voltage support (DVS). Finally, it is shown that (4) complicated and burdensome tasks will be considerably increased in power system operation planning and real‐time operation under future circumstances by the mega penetration of PV. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 184(3): 1–13, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22391
A method for designing the power and capacitance of fuel cells and electric double‐layer capacitors of hybrid railway vehicles
Authors: Takizawa Kenji , Kondo Keiichiro 
Published: May 2013

AbstractA hybrid railway traction system with fuel cells (FC) and electric double‐layer capacitors (EDLC) is discussed in this paper. This system can save FC costs and absorb regenerative energy. A method for designing FC and EDLC on the basis of the output power and capacitance, respectively, has not been reported, although their design is one of the most important technical issues encountered in the design of hybrid railway vehicles. Such a design method is presented along with a train load proﬁle and an energy management strategy. The design results obtained using the proposed method are veriﬁed by performing numerical simulations for a running train. These results reveal that the proposed method for designing the EDLC and FC on the basis of the capacitance and power, respectively, and using a method for controlling the EDLC voltage, is suﬃciently eﬀective in designing eﬃcient EDLC and FC of hybrid railway traction systems. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 184(3): 47–54, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22395