bluuebunny/crossref_metadata_2025 huggingface dataset:
Oligopoly and Price Transmission in Turkey's Fluid Milk Market
Authors: Tekgüç Hasan
Published: February 2013

Farmers and consumers suspect that processing firms abuse their power in the milk marketing chain by engaging in price fixing behavior. The author employs threshold autoregressive and moment threshold autoregressive tests, and contrary to expectations, finds evidence for a downward trend in wholesale milk price without a corresponding decline in farm‐gate prices. The downward trend coincides with increased competition in the dairy industry and with the growing market share of the formal sector at the expense of the informal sector. Major dairy processing firms expand their market share and yet continue to enjoy healthy profits thanks to increasing returns due to economies of scale in their processing and distribution operations in a growing market.
Thermogravimetric study and modeling for the drying of a Chinese lignite
Authors: Tahmasebi Arash , Yu Jianglong , Han Yanna , Zhao Huan , Bhattacharya Sankar
Published: February 2013

Study of drying characteristics and kinetics of coal is necessary in order to optimize drying operation and design a dryer in industrial scale. Drying characteristics of Chinese lignite was investigated experimentally using thermogravimetric method, and the effect of drying variables on drying rate was systematically studied. For CFD modeling and scale‐up purposes, it is useful to have an algebraic equation that describes the drying process of lignite. Therefore, different thin layer drying models given in the literature were employed to analyze coal drying kinetics under different conditions. During studying the consistency of all the models, statistical tests such as χ2, residual sum of squares (RSS), F‐value, and the coefficient of determination R2 were employed. It was found that the Midilli–Kucuk model best describes the drying process within 99.9% accuracy. The effects of drying temperature and coal sample weight on the constants and coefficients of the selected model were also studied by multiple regression analysis. Apparent diffusion coefficient of moisture from sample was calculated using the experimental kinetics data. Higher drying temperatures and smaller sample weights resulted in higher diffusion coefficient, which was consistent with experimental data. Activation energy of moisture evaporation calculated from Arrhenius equation for drying process was 21.17 kJ/mol. The selected algebraic drying model can be used for CFD modeling during scale‐up of drying facility for industrial applications. © 2013 Curtin University of Technology and John Wiley & Sons, Ltd.
Essential work of fracture of poly(ϵ‐caprolactone)/boehmite alumina nanocomposites: Effect of surface coating
Authors: Tuba Ferenc , Khumalo Vincent M. , Karger‐Kocsis József
Published: February 2013

The essential work of fracture (EWF) approach was adopted to reveal the effect of nanofillers on the toughness of poly (ϵ‐caprolactone) (PCL)/boehmite alumina (BA) nanocomposites. Synthetic BA particles with different surface treatments were dispersed into the PCL matrix by extrusion melt compounding. The morphology of the composites was studied by scanning electron microscopy. Differential scanning calorimetry and wide‐angle X‐ray scattering were used to detect changes in the crystalline structure of PCL. Also, mode I type EWF tests, dynamic mechanical analysis, and quasi‐static tensile tests were applied to study the effect of the BA nanofillers on the mechanical properties of the nanocomposites. BA was homogeneously dispersed and acted as heterogeneous crystallization nucleant and a nonreinforcing filler in PCL. The tensile modulus and yield strength slightly increased and the yield strain decreased with increasing BA content (up to 10 wt %). The effect of the BA surface treatment with octylsilane was negligible by contrast to that with alkylbenzene sulfonic acid (OS2). Like the tensile mechanical data, the essential and nonessential work of fracture parameters did not change significantly either. The improved PCL/BA adhesion in case of OS2 treatment excluded the usual EWF treatise. This was circumvented by energy partitioning between yielding and necking. The yielding‐related EWF decreased, whereas the nonessential EWF increased with BA content and with better interfacial adhesion. This was attributed to the effect of matrix/filler debonding. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Modification of ramie fabric with a metal‐ion‐doped flame‐retardant coating
Authors: Wang Lili , Zhang Tao , Yan Hongqiang , Peng Mao , Fang Zhengping
Published: February 2013

Transition‐metal‐ion‐doped flame‐retardant coatings were constructed on the surface of ramie fabrics by a layer‐by‐layer (LbL) assembly technique to investigate possible cooperative actions that could improve the fabric's flame‐retardant efficiency. We found that these functional coatings, consisting of poly(vinylphosphonic acid) (the anionic layer) and branched polyethylenimine/cupric or zinc ions (the cationic layer), improved the fire retardancy of the ramie fabrics remarkably. Attenuated total reflectance–Fourier transform infrared (FTIR) spectroscopy and energy dispersive X‐ray spectroscopy demonstrated the successful LbL assembly process and the incorporation of metal ions into the coating. Thermogravimetric analysis coupled with FTIR spectrometry, vertical flame testing, and microscale combustion calorimetry confirmed the improved thermal stability and reduced flammability of the coated ramie fabrics. All of the results show that the metal‐ion‐doped flame‐retardant coatings not only dramatically increased the residues but also retained the original weave structure and fiber morphology of ramie fabrics well. The enhanced flame‐retardant efficiency may have been caused by the lower decomposition temperature of the flame‐retardant coating, as promoted by cupric and zinc ions, and as a result, may have helped the flame‐retardant activity to take place earlier. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Raster was Yesterday: Using Vector Engines to Process Geophysical Data
Authors: Schmidt Armin , Tsetskhladze Gocha
Published: February 2013

Tools for the processing of raster data are well developed, but noisy data still pose considerable challenges. If anomalies are broken up into isolated individual readings, for example due to high noise levels, it may still be possible for a human interpreter to recognize the isolated readings as being part of a single anomaly. However, such a concept of neighbourhood is difficult to implement with raster tools and an alternative, vector‐based approach is presented here. By converting the measured raster data into polygons, it is possible to undertake shape and neighbourhood analysis to process the data. This allows discriminating, reshaping and merging of the anomalies based on their spatial location relative to each other (neighbourhood) and with respect to the size of each anomaly. The added advantage of this approach is the possibility to use the processed vector data as a basis for interpretation and visualization diagrams in two‐ and three dimensions. This method is applied to the GPR survey of a necropolis at Pessinus, showing several types of grave monuments. Copyright © 2013 John Wiley & Sons, Ltd.
Coronary artery aneurysms
Authors: Wood Frances O. , Trivax Justin E. , Safian Robert D.
Published: February 2013

There is no consensus on the best management of coronary artery aneurysms (CAA) in adults. We describe two patients with CAA and review transcatheter approaches to exclude them from the circulation. © 2013 Wiley Periodicals, Inc.
Continuous Procrustes Distance Between Two Surfaces
Authors: Al‐Aifari Reema , Daubechies Ingrid , Lipman Yaron
Published: February 2013

The Procrustes distance is used to quantify the similarity or dissimilarity of (three‐dimensional) shapes and extensively used in biological morphometrics. Typically each (normalized) shape is represented by N landmark points, chosen to be homologous, as far as possible, and the Procrustes distance is then computed as
$\inf_{R}\sum_{j=1}^N \|Rx_j-x'_j\|^2$, where the minimization is over all euclidean transformations, and the correspondences $x_j \leftrightarrow x'_j$
are picked in an optimal way.

The discrete Procrustes distance has the drawback that each shape is represented by only a finite number of points, which may not capture all the geometric aspects of interest; a need has been expressed for alternatives that are still easy to compute. We propose in this paper the concept of continuous Procrustes distance and prove that it provides a true metric for two‐dimensional surfaces embedded in three dimensions. We also propose an efficient algorithm to calculate approximations to this new distance. © 2012 Wiley Periodicals, Inc.
A framework of data caching for improving decoding efficiency of opportunistic network coding
Authors: Liu Qinglong , Feng Gang
Published: February 2013

Throughput performance of wireless networks can be enhanced by applying network coding (NC) technique based on opportunistic listening. The packets sent or overheard by a network node should be locally cached for the purpose of possible future decoding. How to manage the cache to reduce the overhead incurred in performing NC and, meanwhile, exploit performance gain is an interesting issue that has not been deeply investigated. In this paper, we present a framework for packet caching policy in multihop wireless networks, aiming at improving decoding efficiency, and thus throughput gain of NC. We formulate the caching policy design as an optimization problem for maximizing decoding utility and derive a set of optimization rules. We propose a distributed network coding caching policy (NCP), which can be readily incorporated into various existing NC architectures to improve NC performance gain. We theoretically analyze the performance improvement of NCP over completely opportunistic NC (COPE). In addition, we use simulation experiments based on ns‐2 to evaluate the performance of NCP. Numerical results validate our analytical model and show that NCP can effectively improve the performance gain of NC compared with COPE. Copyright © 2013 John Wiley & Sons, Ltd.
Geographical origin of Leucobryum boninense Sull. & Lesq. (Leucobryaceae, Musci) endemic to the Bonin Islands, Japan
Authors: Oguri Emiko , Yamaguchi Tomio , Tsubota Hiromi , Deguchi Hironori , Murakami Noriaki
Published: February 2013

Leucobryum boninense is endemic to the Bonin Islands, Japan, and its related species are widely distributed in Asia and the Pacific. We aimed to clarify the phylogenetic relationships among Leucobryum species and infer the origin of L. boninense. We also describe the utility of the chloroplast trnK intron including matK for resolving the phylogenetic relationships among Leucobryum species, as phylogenetic analyses using trnK intron and/or matK have not been performed well in bryophytes to date. Fifty samples containing 15 species of Leucobryum from Asia and the Pacific were examined for six chloroplast DNA regions including rbcL, rps4, partial 5′ trnK intron, matK, partial 3′ trnK intron, and trnL‐F intergenic spacer plus one nuclear DNA region including ITS. A molecular phylogenetic tree showed that L. boninense made a clade with L. scabrum from Japan, Taiwan and, Hong Kong; L. javense which is widely distributed in East and Southeast Asia, and L. pachyphyllum and L. seemannii restricted to the Hawaii Islands, as well as with L. scaberulum from the Ryukyus, Japan, Taiwan, and southeastern China. Leucobryum boninense from various islands of the Bonin Islands made a monophylic group that was closely related to L. scabrum and L. javense from Japan. Therefore, L. boninense may have evolved from L. scabrum from Japan, Taiwan, or Hong Kong, or L. javense from Japan. We also described the utility of trnK intron including matK. A percentage of the parsimony‐informative characters in trnK intron sequence data (5.8%) was significantly higher than that from other chloroplast regions, rbcL (2.4%) and rps4 (3.2%) sequence data. Nucleotide sequence data of the trnK intron including matK are more informative than other chloroplast DNA regions for identifying the phylogenetic relationships among Leucobryum species.
Wideband visible wavelength range MEMS Fabry‐Perot Tunable Filter with Ag alloy mirror
Authors: Hirokubo Nozomu , Komatsu Hiroshi , Hashimoto Nobuaki , Sonehara Makoto , Sato Toshiro
Published: February 2013

In this paper we report the structure and the fabrication process of the new microelectromechanical systems (MEMS) Fabry‐Perot Tunable Filter (FPTF) device with Ag alloy mirror which is tunable in the wide wavelength range of visible light. The device has a very simple structure, which consists of two substrates bonded by a novel bonding technology, polymer films, and inert gas plasma treatment. We confirmed that the wavelength of the first‐order transmission peak of the fabricated device can be adjusted to a range of 400 to 700 nm by applying the different DC voltage. Our MEMS FPTF device successfully operates in the wide wavelength range of visible light and shows good agreement with simulation results. © 2013 Wiley Periodicals, Inc. Electron Comm Jpn, 96(3): 17–23, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11451.
Basic study of loss reduction effect by Stator‐Tooth slits in turbine generators. comparison between calculated results of generators and basic experiments
Authors: Yamazaki Katsumi , Nishioka Kazuyoshi , Nakahara Akihito , Furukawa Yoko , Takahashi Kazuhiko , Yabumoto Masao
Published: February 2013

In this study, we investigate the loss reduction effect by stator‐teeth slits in turbine generators on the basis of electromagnetic field analysis and basic experiments. First, the loss reduction effect in the generator is estimated by the 3D finite element method and the theoretical solution of eddy current loss. Next, an experiment using a simple model that simulates the stator‐core ends of the turbine generator is carried out. It is clarified that the loss reduction effect by the slits depends on the frequency, flux density, and permeability of the stator teeth because the loss reduction effect weakens with the skin effect. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(3): 17–25, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22345
Effects of an environmentally relevant polychlorinated biphenyl (PCB) mixture on embryonic survival and cardiac development in the domestic chicken
Authors: Carro Tiffany , Dean Karen , Ottinger Mary Ann
Published: February 2013

A 58-congener polychlorinated biphenyl (PCB) mixture based on contaminant analysis of spotted sandpiper eggs collected along the upper Hudson River, New York, USA, in 2004 was used to study in ovo PCB effects on cardiac development in the domestic chicken. Fertile eggs were injected prior to incubation with the following doses of the PCB mixture: untreated, sham, 0, 0.03, 0.08, 0.3, 0.5, 0.7, and 2.06 µg PCBs/g egg weight (toxic equivalent quotient [TEQ] range of 0.004–0.266 ng/g). In addition, there were untreated and sham-control groups. Embryonic development was monitored throughout incubation and chicks were necropsied at hatch. Hatchability followed a dose-dependent curve with significant (p < 0.05) mortality above the 0.5 µg PCBs/g egg weight treatment compared with controls. The median lethal dose (LD50) of this PCB mixture in hatchling chicks was estimated as 0.4 µg/g egg weight (0.052 ng TEQ/g egg wt) based on the lethality curve. Cardiac arrhythmia was observed at embryonic day 14 of development in embryos treated at concentrations of 0.5 µg/g egg weight and above. Histological analysis was utilized to characterize any cardiac abnormalities. Cardiomyopathies increased across treatments in a dose-dependent manner compared with control groups. Identified abnormalities included the absence of the trabeculated layer of the ventricular wall, ventricular dilation, thinning of the ventricular walls, malformation of the septal wall, and most commonly, absence of the compact layer of the ventricular wall. Chick heart width, depth, total area, compact layer depth, septal width, chamber area, and ventricular wall dimensions did not differ across treatments. The present study supports prior reports of adverse developmental effects of PCBs on cardiovascular systems in birds. Although the eggs hatched, measured cardiomyopathies suggest potential deleterious long-term impacts on individual health and fitness. Environ Toxicol Chem 2013;32:1325–1331. © 2013 SETAC
Estimating population-level HC5 for copper using a species sensitivity distribution approach
Authors: Iwasaki Yuichi , Hayashi Takehiko I. , Kamo Masashi
Published: February 2013

Estimation of population-level benchmark concentrations for protecting aquatic organisms from chemicals is important for value-relevant ecological risk assessments. By employing a species sensitivity distribution (SSD) approach, the authors aimed to derive the population-level hazardous concentration for 5% of species (PHC5) for copper. Based on available information on copper toxicity and population models, the authors estimated population threshold concentrations at which the population size is stable (that is, 0 net population growth) for 13 freshwater species (3 algal, 6 invertebrate, and 4 fish species). The PHC5 for copper was then estimated (6.8 µg/L; 95% confidence interval [CI], 1.8–13.6 µg/L), by fitting a log-normal distribution to the population threshold concentrations obtained. The close overlap between the present study's estimate of the PHC5 and a field-derived threshold concentration suggests that the population-level SSD approach provides a reasonable level of protection for species richness in the natural environment. By contrast, and counterintuitively, the authors' estimate was comparable with the individual-level HC5 reported in the European Union risk assessment. Although the present study cannot determine the underlying reasons for the similar figures, the result provides an indication that the margin between individual-level and population-level benchmarks derived from SSD approaches can be very small. The results therefore suggest that attention is needed to achieve population-level protection using an individual-level SSD approach. Environ Toxicol Chem 2013;32:1396–1402. © 2013 SETAC
Determination of mercury speciation in fish tissue with a direct mercury analyzer
Authors: Barst Benjamin D. , Hammerschmidt Chad R. , Chumchal Matthew M. , Muir Derek C.G. , Smith James D. , Roberts Aaron P. , Rainwater Thomas R. , Drevnick Paul E.
Published: February 2013

Knowledge of Hg speciation in tissue is valuable for assessing potential toxicological effects in fish. Direct Hg analyzers, which use thermal decomposition and atomic absorption spectrometry, have recently gained popularity for determining organic Hg after procedural solvent extraction from some environmental media, although quantitative recovery from lipid-rich materials, such as fish liver, has been problematic. The authors developed a new method by which organic Hg in fish liver and muscle is estimated by the difference between direct measurements of inorganic Hg in an acid extract and total Hg in whole tissue. The method was validated by analysis of a certified reference material (DOLT-4 dogfish liver) and naturally contaminated fish tissues with comparison to an established Hg speciation method (gas chromatography cold vapor atomic fluorescence spectrometry). Recovery of organic Hg from DOLT-4, estimated by difference, averaged 99 ± 5% of the mean certified value for methylmercury. In most liver samples and all muscle samples, estimates of organic Hg from the proposed method were indiscernible from direct speciation measurements of methylmercury (99% ± 6%). Estimation of organic Hg by the difference between total Hg and inorganic Hg was less accurate in liver samples with a high percentage of inorganic Hg (90%). This was because of the increased uncertainty that results from estimating a third value (i.e., organic Hg) by using the difference between two large concentrations (inorganic and total Hg). The proposed method is a useful tool for examining the speciation of Hg in fish muscle and liver, and by extension, potentially other tissues and environmental media. Environ Toxicol Chem 2013;32:1237–1241. © 2013 SETAC
A Jump Diffusion Model for Agricultural Commodities with Bayesian Analysis
Authors: Schmitz Adam , Wang Zhiguang , Kimn Jung‐Han
Published: February 2013

Stochastic volatility, price jumps, seasonality, and stochastic cost of carry have been included separately, but not collectively, in pricing models of agricultural commodity futures and options. We propose a comprehensive model that incorporates all four features. We employ a special Markov chain Monte Carlo algorithm, new in the agricultural commodity derivatives pricing literature, to estimate the proposed stochastic volatility (SV) and stochastic volatility with jumps (SVJ) models. Overall model fitness tests favor the SVJ model. The in‐sample and out‐of‐sample pricing results for corn, soybeans and wheat generally, with few exceptions, lend support for the SVJ model. © 2013 Wiley Periodicals, Inc. Jrl Fut Mark 34:235–260, 2014
Efficient spherical harmonic transforms aimed at pseudospectral numerical simulations
Authors: Schaeffer Nathanaël
Published: February 2013

In this paper, we report on very efficient algorithms for spherical harmonic transform (SHT). Explicitly vectorized variations of the algorithm based on the Gauss‐Legendre quadrature are discussed and implemented in the SHTns library, which includes scalar and vector transforms. The main breakthrough is to achieve very efficient on‐the‐fly computations of the Legendre‐associated functions, even for very high resolutions, by taking advantage of the specific properties of the SHT and the advanced capabilities of current and future computers. This allows us to simultaneously and significantly reduce memory usage and computation time of the SHT. We measure the performance and accuracy of our algorithms. Although the complexity of the algorithms implemented in SHTns are in (where N is the maximum harmonic degree of the transform), they perform much better than any third‐party implementation, including lower‐complexity algorithms, even for truncations as high as N = 1023. SHTns is available at https://bitbucket.org/nschaeff/shtns as open source software.
Upper‐mantle fabrics beneath the Northern Apennines revealed by seismic anisotropy
Authors: Munzarová Helena , Plomerová Jaroslava , Babuška Vladislav , Vecsey Luděk
Published: February 2013

We image anisotropic structure of the upper mantle beneath the Northern Apennines based on body‐wave data collected during the RETREAT experiment (2003–2006). Joint analysis of anisotropic parameters evaluated from independent data sets—teleseismic P‐wave travel times and shear‐wave splitting—allows us to identify regions of different fabrics both in the mantle lithosphere and in the sublithospheric mantle. We recognize three regions—the Tyrrhenian, Adriatic, and Transition—with their own anisotropic characteristics. The slab‐parallel flow prevails in the sublithospheric mantle beneath the thin Tyrrhenian plate, while nearly slab‐perpendicular orientation of the high velocities dominates on the Adriatic side of the region. The asthenospheric‐flow pattern excludes a simple corner‐flow model to fit the fabric of the upper mantle in the syn‐convergent extensional tectonics and suggests the end of the subduction roll‐back. We map fossil anisotropy with inclined symmetry axes within two domains of the thick continental Adriatic lithosphere. We estimate the lithosphere thickness of the Tyrrhenian and Adriatic plates at ~50 km and ~80 km, respectively, the latter being subducted down to no more than ~200 km with indications of inherited frozen‐in anisotropic fabric. If a potential detachment at the northern end of the Apennine slab exists, then it would have to be narrow and in its initial stage. Synthetic tests of the well‐known trade‐off between isotropic heterogeneity and evaluated anisotropic parameters, along with combining independent data sets, document a sufficient separation of both effects.
Triggering of El Niño onset through trade wind–induced charging of the equatorial Pacific
Authors: Anderson Bruce T. , Perez Renellys C. , Karspeck Alicia
Published: February 2013

Sea surface temperature variations over the equatorial Pacific associated with the El Niño/Southern Oscillation (ENSO) produce changes in climates across the globe. Here we report evidence from observationally constrained ocean data for the initiation of warm ENSO events (El Niños) resulting from subsurface equatorial Pacific heat content increases related to tropical/extratropical sea level pressure (SLP) changes over the North Pacific. We hypothesize that the increase in heat content is a response to SLP‐generated variations in the North Pacific trade winds, which we term trade wind charging of the equatorial Pacific. Experiments using a high‐resolution numerical ocean model verify that the charging of subsurface heat content along the equatorial Pacific can be induced by SLP‐generated trade wind variations. Furthermore, analysis of the numerical model results and historical observations indicates that the trade wind–induced ocean heat content increases are sufficiently large to initiate the onset of El Niño events, which mature approximately 12 months after the trade wind forcing itself.
Cracking the MJO nut
Authors: Zhang Chidong , Gottschalck Jon , Maloney Eric D. , Moncrieff Mitchell W. , Vitart Frederic , Waliser Duane E. , Wang Bin , Wheeler Matthew C.
Published: February 2013

The Madden‐Julian oscillation poses great challenges to our understanding and prediction of tropical convection and the large‐scale circulation. Several internationally coordinated activities were recently formed to meet the challenges from the perspectives of numerical simulations, prediction, diagnostics, and virtual and actual field campaigns. This article provides a brief description of these activities and their connections, with the motivation in part to encourage the next generation of physical scientists to help solve the grand challenging problem of the Madden‐Julian oscillation.
Integrating a novel shape memory polymer into surgical meshes decreases placement time in laparoscopic surgery: An in vitro and acute in vivo study
Authors: Zimkowski Michael M. , Rentschler Mark E. , Schoen Jonathan , Rech Bryan A. , Mandava Nageswara , Shandas Robin
Published: February 2013

About 600,000 hernia repair surgeries are performed each year; recently, the use of laparoscopic minimally invasive techniques has become increasingly popular in these operations. Use of surgical mesh in hernia repair has shown lower recurrence rates compared to other repair methods. However in many procedures, placement of surgical mesh can be challenging and even complicate the procedure, potentially leading to lengthy operating times. Various techniques have been attempted to improve mesh placement, including use of specialized systems to orient the mesh into a specific shape, with limited success and acceptance. In this study, a programmed novel Shape Memory Polymer (SMP) was integrated into commercially available polyester surgical meshes to add automatic unrolling and tissue conforming functionalities, while preserving the intrinsic structural properties of the original surgical mesh. Tensile testing and Dynamic Mechanical Analysis was performed on four different SMP formulas to identify appropriate mechanical properties for surgical mesh integration. In vitro testing involved monitoring the time required for a modified surgical mesh to deploy in a 37°C water bath. An acute porcine model was used to test the in vivo unrolling of SMP integrated surgical meshes. The SMP‐integrated surgical meshes produced an automated, temperature activated, controlled deployment of surgical mesh on the order of several seconds, via laparoscopy in the animal model. Results indicate surgical mesh modified with SMP is capable of laparoscopic deployment in vivo, activated by body temperature. This suggests a reduction in surgical operating time and improved mesh placement characteristics is possible with SMP‐integrated surgical meshes. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 2613–2620, 2013.
Hydrodynamic processes and sediment erosion mechanisms in an open channel bend of strong curvature with deformed bathymetry
Authors: Constantinescu G. , Kashyap S. , Tokyay T. , Rennie C. D. , Townsend R. D.
Published: February 2013

Most rivers exhibit regions of strong channel curvature that are characterized by more complex and variable flow and erosion patterns, compared to regions of lower curvature. Studies investigating high‐curvature bends using eddy‐resolving techniques have been limited, and the effect of bend angle on flow and erosion has rarely been investigated. This study investigates flow in a 135° nonerodible bank open channel bend of high curvature: ratio of radius of curvature, R, to channel width, B, is 1.5. The bathymetry is obtained during the final stages of a clear water scour experiment. Large Eddy Simulation is used to investigate the effect of secondary flow on the redistribution of streamwise momentum, the details of coherent structures, and mechanisms leading to erosion within the bend. Results are compared with those from a similar numerical study of a 193° sharply curved open channel bend with R/B = 1.35. The angle of the 135° bend is representative of typical regular meander geometry, while the larger angle of the 193° bend is representative of a tortuous meander geometry. The different bathymetries induced important quantitative and qualitative differences in the vortical and turbulence structure within the open channel for the two cases. Inner bank streamwise‐oriented vortical (SOV) cells formed in both cases, but the position and extent of shear layers forming between regions of fast and slow moving fluid differed, and flow did not separate at the inner bank in the 135° bend. An outer‐bank cell was observed in the 135° bend, but not in the 193° bend. Distributions of predicted boundary shear stresses indicated the capacity of the flow to erode the outer bank of a sharply curved bend under two representative regimes found in the field.
Impact of influenza virus escape‐mutations on influenza detection by the rapid influenza diagnostic test
Authors: Yi Hwajung , Kim Young‐Hoon , Kim Jun‐Sub , Lee Nam‐Joo , Shin Kyeongcheol , Choi Jang‐Hoon , Kwon Donghyok , Lee Joo‐Yeon , Kang Chun
Published: February 2013

During the influenza pandemic of 2009–2010, rapid influenza diagnostic tests (RIDTs) were used to detect influenza viral infections because they are quick and simple to use. However, retrospective studies showed that RIDTs performed poorly when used to diagnose pandemic viral infections. Determining how amino acid sequence changes in pandemic or epidemic influenza viral antigens impact clinical value of RIDTs has not been possible, because the viral epitopes recognized by RIDTs have been not mapped. In this study, the effect of escape‐variations or mutations in influenza viral antigens upon the sensitivity and specificity of an RIDT was investigated by characterizing the immunological properties of the antibodies used in the RIDT. Escape‐mutants were generated by cultivating A/Korea/01/2009 in the presence of an excess of the same antibodies used in the RIDT. Escape‐mutants not recognized by the RIDT were selected. Epitopes recognized by the RIDT were mapped by comparing the sequence and immunological analysis of the escape‐variants and wild‐type isolates. The RIDT antibodies recognized epitopes on the Sa antigenic site and in the F subdomain in hemagglutinin. Variants bearing mutations in these epitopes were not detected by the RIDT. The frequency of escape‐variants emerging since the 2009–2010 pandemic was calculated as 1.27% using in silico surveillance of influenza sequence databases. These results suggest that mapping the relevant epitopes of RIDTs and making such information available to clinics would be helpful for determining whether RIDTs match newly emergent strains and subtypes prior to retrospective re‐evaluation of the RIDTs using clinical specimens. J. Med. Virol. 85:709–715, 2013. © 2013 Wiley Periodicals, Inc.
Effect of pressure and temperature on the molecular interaction of polar lubricant containing oleic acid in polypropylene glycol observed by infrared spectroscopy
Authors: Takiwatari Koji , Nanao Hidetaka , Mori Shigeyuki
Published: February 2013

In this work, we have investigated the infrared spectra of polar lubricant in order to explore the molecular interaction under high pressure and temperature conditions using diamond anvil cell. Polypropylene glycol and oleic acid were used as base oil and additive, respectively. Stretching vibration mode of polar functional groups, such as νO–H and νC═O, was found to be sensitive to pressure and temperature. The peak positions of the vibration mode were shifted clearly to lower wavenumber as pressure increases, and temperature increase induced a slight shift to higher wavenumber. These results indicate that hydrogen bonding between lubricant molecules of base oil and additive was influenced by pressure and temperature. And furthermore, the dependency of the peak shift was discontinuous and affected mainly by pressure. These results imply a structural change on the basis of the molecular interaction of the lubricating molecules at elastohydrodynamic lubrication contacts. Copyright © 2013 John Wiley & Sons, Ltd.
Analytic approximation of the blow‐up time for nonlinear differential equations by the ADM–Padé technique
Authors: Duan Jun‐Sheng , Rach Randolph , Lin Shi‐Ming
Published: February 2013

We present a new approach to calculate analytic approximations of blow‐up solutions and their critical blow‐up times. Our approach applies the Adomian decomposition–Padé method to quickly and easily compute the critical blow‐up times, which comprises the Adomian decomposition method combined with the Padé approximants technique. We validate our new approach with a variety of numerical examples, including nonlinear ODEs, systems of nonlinear ODEs, and nonlinear PDEs. Furthermore, our new method is shown to be more convenient than prior art that relies on compound discretized algorithms. Copyright © 2013 John Wiley & Sons, Ltd.
Nonlinear stability of viscous contact wave for the one‐dimensional compressible fluid models of Korteweg type
Authors: Chen Zhengzheng , Xiao Qinghua
Published: February 2013

This paper is concerned with the large time behavior of solutions of the Cauchy problem to the one‐dimensional compressible fluid models of Korteweg type, which governs the motions of the compressible fluids with internal capillarity. When the corresponding Riemann problem for the Euler system admits a contact discontinuity wave, it is shown that the viscous contact wave corresponding to the contact discontinuity is asymptotically stable provided that the strength of contact discontinuity and the initial perturbation are suitably small. The analysis is based on the elementary L2‐energy method together with continuation argument. Copyright © 2013 John Wiley & Sons, Ltd.
Parallel indirect solution of optimal control problems
Authors: Fabien Brian C.
Published: February 2013

This paper presents an algorithm for the indirect solution of optimal control problems that contain mixed state and control variable inequality constraints. The necessary conditions for optimality lead to an inequality constrained two‐point BVP with index‐1 differential‐algebraic equations (BVP‐DAEs). These BVP‐DAEs are solved using a multiple shooting method where the DAEs are approximated using a single‐step linearly implicit Runge–Kutta (Rosenbrock–Wanner) method. An interior‐point Newton method is used to solve the residual equations associated with the multiple shooting discretization. The elements of the residual equations, and the Jacobian of the residual equations, are constructed in parallel. The search direction for the interior‐point method is computed by solving a sparse bordered almost block diagonal (BABD) linear system. Here, a parallel‐structured orthogonal factorization algorithm is used to solve the BABD system. Examples are presented to illustrate the efficiency of the parallel algorithm. It is shown that an American National Standards Institute C implementation of the parallel algorithm achieves significant speedup with the increase in the number of processors used. Copyright © 2013 John Wiley & Sons, Ltd.
Absolute immature platelet count may predict imminent platelet recovery in thrombocytopenic children following chemotherapy
Authors: Have Laerke Walther Junggreen , Hasle Henrik , Vestergaard Else Marie , Kjaersgaard Mimi
Published: February 2013

Background

Immature platelets are the youngest circulating platelets and they reflect the rate of thrombopoiesis. The immature platelet fraction (IPF) or the absolute immature platelet count (AIPC) may predict platelet count recovery following chemotherapy‐induced thrombocytopenia in pediatric patients and help guiding prophylactic platelet transfusion therapy.

Procedure

To test IPF and AIPC as predictors of platelet recovery, 19 children with platelet nadirs of less than 20 × 109/L after chemotherapy were prospectively enrolled. IPF, platelet count, and C‐reactive protein (CRP) were analyzed in 416 paired samples from 37 patients with malignancies to test if IPF‐levels were CRP dependent.

Results

A significant increase of 0.6 × 109/L in AIPC was seen between 1 and 2 days prior to platelet count recovery. No predictive day‐to‐day differences were found for IPF. Platelet count recovery did not occur significantly earlier for patients with a peak IPF > 10% than for those patients with a peak IPF < 10%. IPF and AIPC showed no correlation to CRP. AIPC was in contrast to IPF not influenced by platelet transfusions.

Conclusion

AIPC increased significantly between 24 and 48 hours before platelet recovery whereas IPF showed no significant increase during the same time period. AIPC may be a better indicator than IPF for predicting platelet recovery after chemotherapy in pediatric patients. Pediatr Blood Cancer 2013; 60: 1198–1203. © 2013 Wiley Periodicals, Inc.
Screening tool for late‐effect pediatric neuro‐oncological clinics: A treatment‐oriented questionnaire
Authors: Greenberg‐Kushnir Noa , Freedman Sigal , Eshel Rina , Zwerdling Nirit , Elhasid Ronit , Dvir Rina , Yalon Michal , Kulkarni Abhaya V. , Constantini Shlomi
Published: February 2013

Background

Many survivors of pediatric brain tumors (SPBTs) suffer from long‐term late effects (LEs). Our aim was to create a practical screening tool for detecting LEs in this population. Such a screening tool will improve our ability to identify those patients who may benefit from treatment in LE clinics while focusing on individual relevant issues.

Procedure

We developed the Treatment‐Oriented Screening Questionnaire (TOSQ); a self‐reported, risk‐based questionnaire that addresses all LEs SPBTs can potentially suffer. As a basis for the TOSQ design we used the Long‐Term Follow‐Up Guidelines published by the Children's Oncology Group. Output includes individual recommendations for further treatment. We prospectively assessed whether the TOSQ can accurately detect treatment targets in SPBTs by comparing patient and caregiver questionnaire scores with physician evaluations. Data are presented from 41 SPBTs.

Results

The TOSQ is a precise screening tool for identifying LEs in SPBTs based on the significant correlation (P < 0.05) that was found between parental scores and physician evaluations. Statistical testing proved that parents are a good source of information about child's health status, and that TOSQ accurately reflects the correlation between patient difficulties and quality of life.

Conclusions

The TOSQ is the first described screening tool for identification of LEs designed specifically for SPBTs. It is simple to use and provides a valid, comprehensive and economic assessment followed by targeted treatment plan for each patient. By repeatedly using the TOSQ over the years, we can improve our ability to detect and give focused treatment to those who require assistance. Pediatr Blood Cancer 2013;60:1369–1374. © 2013 Wiley Periodicals, Inc.
Influence of mesophase–crystal transition on thermal and mechanical properties of stretched poly(L‐lactide)
Authors: Lv Ruihua , Zou Shufen , Na Bing , Deng Huiyu , Yu Zhiwei
Published: February 2013

The mesophase in the as‐stretched poly(L‐lactide) (PLLA) exhibits low thermal stability and undergoes melting around Tg. As a consequence, without constraints as‐stretched PLLA can recover to its original (unstretched) length while being held above Tg. Upon constrained annealing at 70°C mesophase is transformed into highly oriented crystals, responsible for little free shrinkage and superior dimensional stability. At the same time, molecular orientation in the amorphous phase first decreases significantly due to thermodynamic relaxation, and then increases moderately with the advent of cold crystallization. It correlates well with the change of yield strength with respect to annealing time. POLYM. ENG. SCI., 53:2568–2572, 2013. © 2013 Society of Plastics Engineers
Solvent replacement to thermo‐responsive nanoparticles from long‐subchain hyperbranched PSt grafted with PNIPAM for encapsulation
Authors: He Chen , Jin Ban‐Kun , He Wei‐Dong , Ge Xue‐Song , Tao Jing , Yang Jing , Chen Sheng‐Qi
Published: February 2013

Long‐subchain hyperbranched polystyrene (lsc‐hp PSt) with uniform subchain length was obtained through copper‐catalyzed azide‐alkyne cycloaddition click chemistry from seesaw macromonomer of PSt having one alkynyl group anchored at the chain centre and two azido group attached to both chain ends [alkynyl‐(PSt‐N3)2]. After precipitation fraction, different portions of lsc‐hp PSt having narrow overall molecular weight distribution were obtained for further grafting with alkynyl‐capped poly(N‐isopropylacrylamide) (alkynyl‐PNIPAM), which was obtained via single‐electron transfer living radical polymerization of NIPAM with propargyl 2‐bromoisobutyrate as the initiator and grafted onto the peripheral azido groups of lsc‐hp PSt via click chemistry. Thus, amphiphilic lsc‐hp PSt grafted with PNIPAM chains (lsc‐hp PSt‐g‐PNIPAM) was obtained and would have star‐like conformation in tetrahydrofuran (THF). By replacing THF with water, lsc‐hp PSt‐g‐PNIPAM was dissolved at molecular level in aqueous solution due to the hydrophilicity of PNIPAM and exhibited thermal induced shrinkage of PNIPAM arms. The water‐insoluble lsc‐hp PSt would collapse densely and could be served as a reservoir to absorb hydrophobic chemicals in aqueous solution. The influence of overall molecular weight of lsc‐hp PSt on the absorption of pyrene was studied. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
Behavior of N‐oxide derivatives in atmospheric pressure ionization mass spectrometry
Authors: Ibrahim Hany , Couderc François , Perio Pierre , Collin Fabrice , Nepveu Françoise
Published: February 2013

RATIONALE

Indolone‐N‐oxide derivatives possess interesting biological properties. The analysis of these compounds using mass spectrometry (MS) may lead to interference or under‐estimation due to the tendency of the N‐oxides to lose oxygen. All the previous works focused only on the temperature of the heated parts (vaporizer and ion‐transfer tube) of the mass spectrometer without investigating other parameters. This work is extended to the investigation of other parameters.

METHODS

The behavior of N‐oxides during atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI) has been investigated using MSn ion trap mass spectrometry. Different parameters were investigated to clarify the factors implicated in the deoxygenation process. The investigated parameters were vaporizer temperature (APCI), ion‐transfer tube temperature, solvent type, and the flow rates of the sheath gas, auxiliary gas, sweep gas and mobile phase.

RESULTS

The deoxygenation increased when the vaporizer temperature increased. The extent of the 'thermally' induced deoxygenation was inversely proportional to the ion‐transfer tube temperature and auxiliary gas flow rate and in direct proportion to the mobile phase flow rate. Deoxygenation was not detected under MS/MS fragmentation and hence it is a non‐collision‐induced dissociation. N‐Oxides have the tendency to form abundant 'non‐classical' dimers under ESI, which fragment via dehydration rather than giving their corresponding monomer.

CONCLUSIONS

Deoxygenation is not solely a 'classical' thermal process but it is a thermal process that is solvent‐mediated in the source. Deoxygenation was maximal with an APCI source while dimerization was predominant with an ESI source. Therefore, attention should be paid to these molecular changes in the mass spectrometer as well as to the choice of the ionization mode for N‐oxides. Copyright © 2013 John Wiley & Sons, Ltd.
Design of a low‐temperature plasma (LTP) probe with adjustable output temperature and variable beam diameter for the direct detection of organic molecules
Authors: Martínez‐Jarquín Sandra , Winkler Robert
Published: February 2013

RATIONALE

The direct detection of organic molecules by mass spectrometry requires ionization methods which are compatible with ambient conditions. A relatively new strategy is the use of a free low‐temperature plasma beam for ionization. The objective is to design a safe and adjustable plasma beam to enable optimal ionization and desorption parameters for specific molecules.

METHODS

A plasma probe based on a dielectric barrier discharge was designed, where the plasma is guided through an internal second tube. This setup permits different beam diameter settings and the control of the plasma temperature. The ionization and desorption of pure organic compounds, as well as their direct detection from roasted coffee beans, were tested.

RESULTS

The presented plasma probe provides improved safety with respect to arcing, ozone generation and electric shock, compared with conventional designs. The functionality of previously reported devices is expanded. A defined plasma diameter can be set by choosing the appropriate insert, while the input voltage controls the plasma temperature. The variation of measurement parameters enables the optimized direct detection of target compounds from roasted coffee beans, such as caffeine, guaiacol and vanillin.

CONCLUSIONS

The presented low‐temperature plasma probe allows the fine‐tuning of ionization and desorption parameters, according to the target molecules. Possible applications include: (1) The ambient ionization and desorption of organic compounds with different volatility and (2) The direct analysis of food products such as roasted coffee beans. Copyright © 2013 John Wiley & Sons, Ltd.
AAPL: assessing association between p‐value lists
Authors: Yu Tianwei , Zhao Yize , Shen Shihao
Published: February 2013

Joint analyses of high‐throughput datasets generate the need to assess the association between two long lists of p‐values. In such p‐value lists, the vast majority of the features are insignificant. Ideally contributions of features that are null in both tests should be minimized. However, by random chance their p‐values are uniformly distributed between 0 and 1, and weak correlations of the p‐values may exist due to inherent biases in the high‐throughput technology used to generate the multiple datasets. Rank‐based agreement test may capture such unwanted effects. Testing contingency tables generated using hard cutoffs may be sensitive to arbitrary threshold choice. We develop a novel method on the basis of feature‐level concordance using local false discovery rate. The association score enjoys straight‐forward interpretation. The method shows higher statistical power to detect the association between p‐value lists in simulation. We demonstrate its utility using real data analysis. The R implementation of the method is available at http://userwww.service.emory.edu/∼tyu8/AAPL/. © 2013 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 6: 144–155, 2013