bluuebunny/crossref_metadata_2025 huggingface dataset:
Collective Information Filtering for Web Observatories
Authors: Nanas Nikolaos , Vavalis Manolis , Kellis Lefteris , Koutsaftikis Dimitris , Houstis Elias
Published: July 2010

Web observatories are becoming a common on-line practice. Their role is to compile, organize and convey information that serves the needs of a thematically focused Web community. So far they are typically following a centralized approach, with an editorial team being responsible for finding, collecting, editing and presenting the observatory‘s information content. We propose a new approach for the development of Web observatories based on Collective Information Filtering. Community profiles are used to capture the collective interests of community members and evaluate the relevance of information content accordingly. We can thus build Web observatories that can be dynamically enriched and can continuously adapt their content to the interests/needs of the observatory‘s community. This new approach not only reduces significantly the cost of developing and maintaining a Web observatory, but also, following the current Web trends, it is community driven. In this chapter, we discuss Collective Information Filtering and we describe the architecture for applying it to a Web Observatory. We also present a series of prototype Web Observatories that adopt the proposed approach.
Applications of a Social Software Model
Authors: Coenen Tanguy , Van den Bosch Wouter
Published: July 2010

This paper discusses social software technologies and presents an integrated social software model that can be used to achieve collective goals. This model has grown out of a need among practitioners to identify useful social software functionalities and to find out what to do with them. As the number of social software technologies increases, the question increasingly remains what to do with them and how to apply them usefully. The model can be used within an organization, to guide it in attaining organizational goals, but it can also be used to support activities in a network of organizations or in a network of non-affiliated individuals. First, we discuss social software in general. Subsequently, we discuss a model for understanding social software data and functionality. Finally, two possible applications of the social software model are discussed: knowledge sharing and increasing social inclusion among youth.
Social and Ethical Concerns of Biomedical Engineering Research and Practice
Authors: Mishra Snehasish
Published: July 2010

Biomedical engineering is an advanced and relatively new field in the healthcare sector. Owing to the very nature of the various professional challenges faced by healthcare professionals, the moral and ethical values seem to have taken the backburner. The factors contributing to it may include a sound knowledge of the healthcare professional on the legally-permissible ethical values, and the desperate situations requiring precise split-moment decision-making. No technological advancement without a human face is worth it, and hence, during the course of the degree, a biomedical engineering student needs to be exposed to various ethical issues through theory, live cases and demonstrations. Being intrinsically multi- and inter-disciplinary, biomedical engineering lacks precise ethical rules that delineate and delimit professional responsibility, thus blurring the ethical understanding of biomedical engineering. The solution seems to lie in giving due place to human virtues. In the coming days, bioethical issues are expected to be increasingly complicated and dominating the decision-making process owing to the advancements in sciences, and the ever-complicated cases handled by healthcare professionals. A global healthcare and ethics-related online open-access portal may serve as a common platform for all the stakeholders in the interest and ethical growth of biomedical engineering in particular and medical sciences in general.
Methods for Improving Foot Displacement Measurements Calculated from Inertial Sensors
Authors: Charry Edgar , Lai Daniel T.H.
Published: July 2010

The use of inertial sensors to measure human movement has recently gained momentum with the advent of low cost micro-electro-mechanical systems (MEMS) technology. These sensors comprise accelerometer and gyroscopes which measure accelerations and angular velocities respectively. Secondary quantities such as displacement can be obtained by integration of these quantities, a method which presents challenging issues due to the problem of accumulative sensor errors. This chapter investigates the spectral evaluation of individual sensor errors and looks at the effectiveness of minimizing these errors using static digital filters. The primary focus is on the derivation of foot displacement data from inertial sensor measurements. The importance of foot, in particular toe displacement measurements is evident in the context of tripping and falling which are serious health concerns for the elderly. The Minimum Toe Clearance (MTC) as an important gait variable for falls-risk prediction and assessment, and therefore the measurement variable of interest. A brief sketch of the current devices employing accelerometers and gyroscopes is presented, highlighting the problems and difficulties reported in literature to achieve good precision. These have been mainly due to the presence of sensor errors and the error accumulative process employed in obtaining displacement measurements. The investigation first proceeds to identify the location of these sensor errors in the frequency domain using the Fast Fourier Transform (FFT) on raw inertial sensor data. The frequency content of velocity and displacement measurements obtained from integrating the inertial data using a well known strap-down method is then explored. These investigations revealed that large sensor errors occurred mainly in the low frequency spectrum while white noise exists in all frequency spectra. The efficacy of employing a band-pass filter to remove a large portion of these errors and their effect on the derived displacements is elaborated on. The cross-correlation of the FFT power spectra from a highly accurate optical measurement system and processed sensor data is used as a metric to evaluate the performance of the band-pass filter at several stages of the processing stage. The motivation is that a more fundamental method would require less computational demand and could lead to more efficient implementations in low-power and systems with limited resources, so that portable sensor based motion measurement system would provide a good degree of measurement accuracy.
E-Medical Education
Authors: Doyle D. John
Published: July 2010

The World Wide Web has made available a large variety of medical information and education resources only dreamed of two decades ago. This review discusses a number of Web-based e-Medical education concepts and resources likely to be of interest to the medical education community as well as a number of other groups. The resources described focus especially on those that are free and those that have an interactive component. The importance of interactivity and its role in the “constructivist” approach to education is emphasized. Problem-based learning in medical education is also discussed. In addition, the importance of “Web 2.0” and related developments is discussed, along with an overview of Web-based medical simulation software that can complement medical education programs. The importance of podcasts and videocasts as an educational resource are also emphasized. Other concepts such as mashups and the semantic Web are briefly described. Intellectual property issues are also discussed, such as Creative Commons license arrangements, as well as the concept of “information philanthropy”. Finally, the importance of peer-review and technology evaluation for online educational materials is discussed.
Cryopreservation of Spermatozoa
Authors: Kundu Chanakya Nath , Majumder Gopal C. , Preet Ranjan
Published: July 2010

Cryopreservation of sperm has many applications in agriculture, biotechnology, and clinical medicine. The spermatozoon is a very specialized cell that loses the ability of biosynthesis, repair, growth and cell division during the final phase of spermatogenesis. Cryopreservation of sperm generally requires a reduction or arrest of the metabolism of cells, thereby prolonging their life. Semen samples of mammalian species are diluted with a suitable diluent [containing a complex extender (e.g., egg-yolk, milk, milk-whey), cryoprotectant (e.g., glycerol)] and processed through different freezing protocol prior to storage in liquid nitrogen (-196°C). Despite the use of complex media and cryoprotectants, a substantial portion of the cells die during freezing and thawing (recovery rate do not exceeds more than 50%). As the complex media contain large numbers of undefined biomolecules (proteins, lipids, carbohydrates), it is difficult to analyze the beneficial/detrimental effects of a particular compound on sperm cryopreservation. In the present book chapter we have briefly discussed the knowledge and limitations of the current semen cryopreservation technology and mainly focused on the development of a simple cryopreservation model using chemically-defined medium and goat cauda-epididymal sperm. Using this model system, several novel cryoprotectants have been identified and biochemical basis of sperm membrane damage during cryopreservation has been investigated.
The Fundamental Group ofS1-manifolds
Authors: Godinho Leonor , Sousa-Dias M. E.
Published: July 2010

We address the problem of computing the fundamental group of a symplecticS1-manifold for non-Hamiltonian actions on compact manifolds, and for Hamiltonian actions on non-compact manifolds with a proper moment map. We generalize known results for compact manifolds equipped with a HamiltonianS1-action. Several examples are presented to illustrate our main results.
Curvature Bounds for Surfaces in Hyperbolic 3-Manifolds
Authors: Breslin William
Published: July 2010

A triangulation of a hyperbolic 3-manifold is L-thick if each tetrahedron having all vertices in the thick part of M is L-bilipschitz diffeomorphic to the standard Euclidean tetrahedron. We show that there exists a fixed constant L such that every complete hyperbolic 3-manifold has an L-thick geodesic triangulation. We use this to prove the existence of universal bounds on the principal curvatures of π1-injective surfaces and strongly irreducible Heegaard surfaces in hyperbolic 3-manifolds.
Riemann Extensions of Torsion-Free Connections with Degenerate Ricci Tensor
Authors: Calviño-Louzao E. , García-Río E. , Vázquez-Lorenzo R.
Published: July 2010

Correspondence between torsion-free connections with nilpotent skew-symmetric curvature operator and IP Riemann extensions is shown. Some consequences are derived in the study of four-dimensional IP metrics and locally homogeneous affine surfaces.
A probabilistic measure of air traffic complexity in 3‐D airspace
Authors: Prandini Maria , Putta Vamsi , Hu Jianghai
Published: July 2010

In this paper, we propose a new method to evaluate air traffic complexity in 3‐D airspace through a probabilistic measure of the airspace occupancy. The key novelty of the approach is that uncertainty in the future aircraft positions is explicitly accounted for when evaluating complexity. Analytic—though approximate—expressions of the complexity measure are derived.

Prospective applications for the proposed complexity metric include the timely identification of those multi‐aircraft conflict situations that would be difficult to solve because of limited maneuverability space, and the design of trajectories so as to avoid congested regions that would require many tactical maneuvers to pass them through. Numerical examples are provided to illustrate the approach. Copyright © 2010 John Wiley & Sons, Ltd.
Highly Enantioselective Michael Addition of Cyclic 1,3‐Dicarbonyl Compounds to β,γ‐Unsaturated α‐Keto Esters
Authors: Chen Xing‐Kuan , Zheng Chang‐Wu , Zhao Sheng‐Li , Chai Zhuo , Yang Ying‐Quan , Zhao Gang , Cao Wei‐Guo
Published: July 2010

A highly enantioselective Michael addition of cyclic 1,3‐dicarbonyl compounds to β,γ‐unsaturated α‐keto esters catalyzed by amino acid‐derived thiourea‐tertiary‐amine catalysts is presented. Using 5 mol% of a novel tyrosine‐derived thiourea catalyst, a series of chiral coumarin derivatives were obtained in excellent yields (up to 99%) and with up to 96% ee under very mild conditions within a short reaction time.
The First Example of Saccharin‐Lithium Bromide Catalysis: Direct Synthesis of N‐Tosylimines from Alcohols
Authors: Patel Rajesh , Srivastava Vishnu P. , Yadav Lal Dhar S.
Published: July 2010

The first procedure to access N‐tosylimines directly from alcohols under mild and neutral conditions is reported. The protocol involves saccharin‐lithium bromide‐catalyzed oxidation of alcohols to aldehydes/ketones with chloramine‐T followed by their condensation with the in situ generated oxidation by‐product p‐toluenesulfonamide in the same reaction vessel to afford N‐tosylimines in 40–90% overall yields. The present work opens up a new and efficient synthetic route to N‐tosyimines directly from alcohols in a one‐pot procedure.
Magnetic resonance imaging study of complex flow of viscoelastic fluids
Authors: Maddinelli Giuseppe , Guarneri Alberto , Carminati Stefano
Published: July 2010

NMR imaging techniques have been applied to investigate complex fluid dynamics in pipes and in annular flow conditions. In this application, aimed to simulate drilling and production operations, two lines have been set up to reproduce, at small laboratory scale, respectively, a pipe flow and an annular flow that are typical flow geometries in oilfield wells during drilling. NMR imaging measurements have been performed inside a horizontal‐bore magnet with a fluid flow assured in a velocity range of 10–100 cm s−1. The studies were dedicated to investigate the different flow regimes associated to circulating viscous polymer solutions applied in drilling mud formulations. Early transitions from laminar to turbulent regime were observed at very low Reynolds number (in a range between 300 and 500, to be compared with the theoretical transition value greater than 2100). © 2010 American Institute of Chemical Engineers AIChE J, 2011
Study on degradation reactions in polyethylene terephthalate containing 5‐sulpho isophthalyl moieties
Authors: Nayak Shilpa , Labde Jayprakash , Geedh Santosh , Jaisingh Sanjiv K. , Rao Krishna , Venkatachalam S. , Kelkar Anil K.
Published: July 2010

Kinetics of thermal degradation occurring on polyester containing cationic dyeable comonomer units viz. 5‐sulphoisophthalate moieties are studied by measurement of changes in intrinsic viscosity and carboxyl values on the polymer after subjecting the polymer chips to temperatures in the range 275–285°C for different residence times ranging from 5 to 60 min and comparing with the homopolymer. The activation energy values for degradation are estimated from the kinetic data. Mechanical properties of the textured yarns produced from the partially oriented yarns (POY) spun under different residence times are measured. Yarn produced with higher residence time has poor mechanical properties. The SEM images of the POY show presence of particles at the surface of the yarn due to polymer degradation. The size of the particles as seen on the surface increase with increase of retention time. Addition of thermal stabilizer helps in controlling the thermal degradation. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Acid‐synergized grafting of sodium styrene sulfonate onto electron beam irradiated‐poly(vinylidene fluoride) films for preparation of fuel cell membrane
Authors: Nasef Mohamed Mahmoud , Saidi Hamdani , Dahlan Khairul Zaman Mohd
Published: July 2010

The role of acid addition in synergizing radiation induced grafting of sodium styrene sulfonate (SSS) onto electron beam‐irradiated poly(vinylidene fluoride) (PVDF) films as a single‐step route for preparation of proton exchange membranes containing sulfonic acid groups was systematically investigated. The grafting reaction, known for its poor kinetics, was studied using SSS diluted in various solvents and solvent/acid solutions of different concentrations and volumes. The addition of acid solution was found to marvelously synergize the grafting reaction from very low values (e.g., 0.5%) to achieve high degrees (e.g., 65%) of grafting and such synergetic effect depends on the type, concentration and volume of the added acid. The degree of grafting was also found to be function of the monomer concentration and the irradiation dose at constant acid concentration and volume. The obtained membranes were investigated with Fourier transform infrared spectroscopy (FTIR), scanning transmission electron microscopy (STEM), and X‐ray diffractometry (XRD). The results of present study reveal that grafting of SSS to levels suitable for fuel cell application onto PVDF film is only possible by adding aqueous acids solution. Moreover, the addition of acid makes this shorter single‐step method more economical route for preparation of proton exchange membranes for fuel cells. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The effect of different modified multiwalled carbon nanotubes on tribological behaviors of poly(furfuryl alcohol) composite coatings
Authors: Men Xue Hu , Zhang Zhao Zhu , Yang Jin , Wang Kun , Jiang Wei
Published: July 2010

Three kinds of modified multiwalled carbon nanotubes (MWNTs) with different length were obtained by grafting carboxylic groups on long MWNTs or copolymer groups on short and long MWNTs. The modified MWNTs were examined by infrared spectroscopy, thermal gravimetric analysis, X‐ray photoelectron spectroscopy, and field emission scanning electron microscopy (FESEM). Afterward, the modified MWNTs were introduced into poly (furfuryl alcohol) (PFA), and the tribological behaviors of the resultant PFA composite coatings were investigated using a ring‐on‐block wear tester under dry friction condition. The dispersion of MWNTs in PFA composites and the worn surfaces were investigated by FESEM. The results indicated that the MWNTs dispersion and the tribological behaviors of PFA composite coatings could be obviously improved by modification with the copolymer. More significantly, under similarly uniform dispersion of MWNTs, the tribological properties of PFA composite coatings with short nanotubes presented better results when compared with those with long nanotubes because of the influence of nanotube length on the degree of modification of the MWNTs surfaces. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Influence of the recycled glass fibers from nonmetals of waste printed circuit boards on properties and reinforcing mechanism of polypropylene composites
Authors: Zheng Yanhong , Shen Zhigang , Ma Shulin , Cai Chujiang , Zhao Xiaohu , Xing Yushan , Guo Baohua , Zeng Xinmiao , Wang Liancai
Published: July 2010

The feasibility of reusing the recycled glass fibers (RGF) from nonmetals of waste printed circuit boards in polypropylene (PP) composites is studied by mechanical properties, vicat softening temperature and heat distortion temperature. The influence of RGF on reinforcing mechanism of the composites is watched under scanning electron microscopy (SEM) in situ tensile test. The results show that the mechanical and thermal properties of the RGF/PP composites can be significantly improved by adding the RGF into PP. In situ SEM observation results show that the RGF are the excellent supporting bodies and can effectively lead to mass microcracks. Crack initiation, propagation, and fiber breakage dissipate tremendous energy. Therefore, the mechanical properties are reinforced. All the above results indicate that the reuse of RGF in the PP composites represents a promising way for closing the recycling loop and realizing the high added value utilization. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Cellulose as a renewable resource for the synthesis of wood consolidants
Authors: Cipriani Giacomo , Salvini Antonella , Baglioni Piero , Bucciarelli Erica
Published: July 2010

Crosslinkable cellulose ethers as allyl cellulose, allyl carboxymethyl cellulose, and allyl n‐hydroxypropyl cellulose were synthesized and characterized, and their use as consolidating agents for waterlogged wood was studied. For this kind of application, structural properties similar to those of wood's polysaccharide components are desired in the design stage of new consolidants. The choice to synthesize cellulose ethers was determined from the possibility of using cellulose as the starting material because of its large availability in nature, biocompatibility, and low cost. In addition, cellulose ethers are quite easy to obtain, and they can have different properties, depending on the nature and the amount of the functional groups introduced. For this purpose, a cellulose with a lower degree of polymerization was also used for the synthesis of related cellulose ethers. By means of Fourier transform infrared spectroscopy, the affinity of the cellulose derivatives for degraded lignin flours was detected. The preliminary results of this study show that these polysaccharide compounds may be proposed as wood consolidating agents. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis and solution properties of amphiphilic cyclopolymers and terpolymers of 4‐methoxycarbonyl‐1,1‐diallylpiperidinium chloride, diallyloctadecylammonium chloride, and sulfur dioxide
Authors: Ali Shaikh A. , Al‐Muallem Hasan A. , Abu‐Thabit N. Y.
Published: July 2010

The cycloterpolymerization of a hydrophilic monomer, 4‐methoxycarbonyl‐1,1‐diallylpiperidinium chloride, with a hydrophobic monomer, diallyloctadecylammonium chloride (3–7 mol %), and sulfur dioxide in dimethyl sulfoxide with azobisisobutyronitrile as the initiator afforded a series of water‐soluble cationic polyelectrolytes (CPEs) at well over 90% yields. Acidic (HCl) hydrolysis of the ester groups in CPEs to CO2H groups gave the cationic acid salts (CASs), which on treatment with 1 equiv of NaOH, furnished polyzwitterions (PZs). Contrary to the well‐known behavior that the normal PZs are only soluble in brine, PZ in the absence of the hydrophobe was found to be soluble in salt‐free water. The solution properties of the resulting series of interconvertible polymers (CPE → CAS ⇋ PZ) were investigated by viscometric techniques. At a shear rate of 0.36 s−1, 2 g/dL solutions of CPE having 0, 3, 5, and 7 mol % hydrophobe in salt‐free water at 30°C were found to have apparent viscosity values of 4000, 164,000, 670,000, and 1,430,000 cps, respectively. Polymer–surfactant interactions were investigated with the cationic surfactant cetyltrimethylammonium bromide (CTAB). Tremendous increases in the viscosity values of the CPE having 7 mol % of the hydrophobe were observed in the presence of the surfactant at a shear rate of 0.36 s−1; a 0.75 g/dL solution of the polymer in salt‐free water was found to have apparent viscosity values of 18,000 and 235,000 cps in the absence and presence, respectively, of 3 mM CTAB. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Improved surface wettability of polyurethane films by ultraviolet ozone treatment
Authors: Kuang Ping , Lee Jae‐Hwang , Kim Chang‐Hwang , Ho Kai‐Ming , Constant Kristen
Published: July 2010

The wettability of polyurethane (PU) was altered using ultraviolet ozone (UVO) treatment. The effect of UVO treatment on PU surface chemistry was investigated with various experiments. The direct measurement of sessile drops was employed to quantify the static contact angle of different wetting liquids on homogeneous PU films with various UVO treatment times. The contact angle of DI water droplets was decreased to 17.2° from 70.04° after 5 min UVO treatment. The surface free energy of PU films was 51.46 mN m−1 before treatment and was increased to 71.5 mN m−1 after being fully treated. X‐ray photoelectron spectroscopy (XPS) analysis shows a significant amount of polar functional species (CO and CO bonding) were formed on the PU surface by UVO treatment. atomic force microscopy (AFM) characterization shows the PU surface morphology was different before and after UVO treatment. The effect of water washing on UVO treated surface was also investigated. An aging effect study indicates the UVO modification can sustain the improved wettability with limited hydrophobic recovery, where the DI water contact angle remains constant at around 22° after the UVO treatment. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Influence of filler and cure systems on thermal aging resistance of natural rubber vulcanizates under strained condition
Authors: Choi Sung‐Seen , Jose Jobin , Lyu Min‐Young , Huh Yang‐Il , Cho Baik Hwan , Nah Changwoon
Published: July 2010

Aging and decomposition of polymer based articles are influenced by various environmental factors. Hence, it is important to research the various factors precisely to interpret the aging mechanism. This study deals with the tensile set properties of natural rubber (NR) vulcanizates with different reinforcing and cure systems after thermal aging. The tensile set increased with increasing both the aging temperature and aging period. Thermal aging resistance and tension set was enhanced by increasing the cure accelerator content in the sample. The carbon black‐filled NR vulcanizates showed better thermal aging resistance than the silica‐filled ones. It was found that silane coupling agent enhanced the thermal aging resistance of the silica‐filled NR vulcanizates. The experimental results could be explained by the cross‐link density change and also from the consumption of the antidegradants due to thermal aging. The permanent tension set and cross‐link density were increased as the aging temperature and aging time were increased. The filler and cure systems were found to influence on the surface morphologies of the thermally aged samples. The cross‐link density change was a key factor of the changes of tension set. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Molecular characterization ofmariner‐like elements in emerald ash borer,Agrilus planipennis(Coleoptera, Polyphaga)
Authors: Rivera‐Vega L. , Mittapalli O.
Published: July 2010

Emerald ash borer (EAB, Agrilus planipennis), an exotic invasive pest, has killed millions of ash trees (Fraxinus spp.) in North America and continues to threaten the very survival of the entire Fraxinus genus. Despite its high‐impact status, to date very little knowledge exists for this devastating insect pest at the molecular level. Mariner‐like elements (MLEs) are transposable elements, which are ubiquitous in occurrence in insects and other invertebrates. Because of their low specificity and broad host range, they can be used for epitope‐tagging, gene mapping, and in vitro mutagenesis. The majority of the known MLEs are inactive due to in‐frame shifts and stop codons within the open reading frame (ORF). We report on the cloning and characterization of two MLEs in A. planipennis genome (Apmar1 and Apmar2). Southern analysis indicated a very high copy number for Apmar1 and a moderate copy number for Apmar2. Phylogenetic analysis revealed that both elements belong to the irritans subfamily. Based on the high copy number for Apmar1, the full‐length sequence was obtained using degenerate primers designed to the inverted terminal repeat (ITR) sequences of irritans MLEs. The recovered nucleotide sequence for Apmar1 consisted of 1,292 bases with perfect ITRs, and an ORF of 1,050 bases encoding a putative transposase of 349 amino acids. The deduced amino acid sequence of Apmar1 contained the conserved regions of mariner transposases including WVPHEL and YSPDLAP, and the D,D(34)D motif. Both Apmar1 and Apmar2 could represent useful genetic tools and provide insights on EAB adaptation. © 2010 Wiley Periodicals, Inc.
Stepped frequency ground‐penetrating radar survey with a multi‐element array antenna: Results from field application on archaeological sites
Authors: Linford Neil , Linford Paul , Martin Louise , Payne Andy
Published: July 2010

A series of trial geophysical surveys were conducted with a 3d‐Radar GeoScope ground‐penetrating radar (GPR) utilizing a multi‐element array antenna. This system offers the potential for rapid data acquisition at very high sample densities over a wide frequency bandwidth. Field tests, conducted over the Roman town at Silchester, Hampshire, UK, suggested that a revised antenna configuration was necessary to obtain optimum results from the system, which was then successfully deployed in the collection of over 5 ha of survey data at a sample density of 0.075 m × 0.075 m. The wide area survey produced a wealth of archaeological detail to complement and expand upon the extensive record of excavation, aerial photography and other geophysical results. Initial trial surveys were conducted with a range of antenna arrays (B2431, B1831 and B1823) incorporating different sized elements to fully exploit the wide potential bandwidth of the system. However, the differing response of elements proved difficult to combine within a single data set and a marked increase in quality was obtained with the use of a prototype V1821 antenna array of identical sized elements. Some concerns remain regarding both the suitability of air‐launched antenna arrays to certain site conditions, as one early survey visit to Silchester produced very poor results that remain unexplained, and the maximum penetration depth compared with an impulse GPR using ground‐coupled antenna. © 2010 Crown copyright.
Modeling and simulation of vehicle projection arrival–discharge process in adaptive traffic signal controls
Authors: Fang Fang Clara , Elefteriadou Lily
Published: July 2010

Real‐time signal control operates as a function of the vehicular arrival and discharge process to satisfy a pre‐specified operational performance. This process is often predicted based on loop detectors placed upstream of the signal. In our newly developed signal control for diamond interchanges, a microscopic model is proposed to estimate traffic flows at the stop‐line. The model considers the traffic dynamics of vehicular detection, arrivals, and departures, by taking into account varying speeds, length of queues, and signal control. As the signal control is optimized over a rolling horizon that is divided into intervals, the vehicular detection for and projection into the corresponding horizon intervals are also modeled. The signal control algorithm is based on dynamic programming and the optimization of signal policy is performed using a certain performance measure involving delays, queue lengths, and queue storage ratios. The arrival–discharge model is embedded in the optimization algorithm and both are programmed into AIMSUN, a microscopic stochastic simulation program. AIMSUN is then used to simulate the traffic flow and implement the optimal signal control by accessing internal data including detected traffic demand and vehicle speeds. Sensitivity analysis is conducted to study the effect of selecting different optimization criteria on the signal control performance. It is concluded that the queue length and queue storage ratio are the most appropriate performance measures in real‐time signal control of interchanges. Copyright © 2010 John Wiley & Sons, Ltd.
Hybrid model for prediction of bus arrival times at next station
Authors: Yu Bin , Yang Zhong‐Zhen , Chen Kang , Yu Bo
Published: July 2010

Effective prediction of bus arrival times is important to advanced traveler information systems (ATIS). Here a hybrid model, based on support vector machine (SVM) and Kalman filtering technique, is presented to predict bus arrival times. In the model, the SVM model predicts the baseline travel times on the basic of historical trips occurring data at given time‐of‐day, weather conditions, route segment, the travel times on the current segment, and the latest travel times on the predicted segment; the Kalman filtering‐based dynamic algorithm uses the latest bus arrival information, together with estimated baseline travel times, to predict arrival times at the next point. The predicted bus arrival times are examined by data of bus no. 7 in a satellite town of Dalian in China. Results show that the hybrid model proposed in this paper is feasible and applicable in bus arrival time forecasting area, and generally provides better performance than artificial neural network (ANN)–based methods. Copyright © 2010 John Wiley & Sons, Ltd.
IF‐EM: An interval‐parameter fuzzy linear programming model for environment‐oriented evacuation planning under uncertainty
Authors: Tan Qian , Huang Guo H. , Wu Chaozhong , Cai Yanpeng
Published: July 2010

The processes and factors involved in evacuation activities are associated with a variety of uncertainties, posing major challenges to evacuation planners. This study represents an attempt to employ inexact optimization techniques for addressing uncertainties in evacuation practices. In this study, an interval‐parameter fuzzy evacuation management (IF‐EM) model is developed for supporting environment‐oriented evacuation management under uncertainty. Through IF‐EM, uncertainties in the model's stipulations and coefficients which are expressed as fuzzy sets and interval numbers can be directly communicated into the optimization process, greatly enhancing the robustness of the optimization system. The model is then applied to a case study and solved through a two‐step interactive algorithm. A number of evacuation schemes can be generated by adjusting decision variables within their solution intervals according to projected planning conditions, reflecting various decision policies and a compromise between system optimality and stability. The relationships among vehicle allocation pattern, evacuation time, system satisfaction level, and system reliability level can be effectively reflected, facilitating more in‐depth analyses of interactions among system efficiency, environmental protection, and economic cost. Results from the case study suggest that the proposed IF‐EM model is applicable to practical evacuation problems that are associated with uncertainties and complexities. Copyright © 2010 John Wiley & Sons, Ltd.
Kinetics of the self‐aggregation and film formation of poly‐L‐proline at high temperatures explored by circular dichroism spectroscopy
Authors: Tooke Lonna , Duitch Laura , Measey Thomas J. , Schweitzer‐Stenner Reinhard
Published: July 2010

Poly‐L‐proline has been used as a model system for various purposes over a period of more than 60 years. Its relevance among the protein/peptide community stems from its use as a reference system for determining the conformational distributions of unfolded peptides and proteins, its use as a molecular ruler, and from the pivotal role of proline residues in conformational transitions and protein–protein interactions. While several studies indicate that polyproline can aggregate and precipitate in aqueous solution, a systematic study of the aggregation process is still outstanding. We found, by means of UV‐circular dichroism and IR measurements, that polyproline is predominately monomeric at room temperature at millimolar concentrations. Upon heating, the polypeptide stays in its monomeric state until the temperature reaches a threshold of ca. 60°C. At higher temperatures, the peptide aggregates as a film on the inside surface of the employed cuvette. The process proceeds on a time scale of 103 s and can best be described by a bi‐exponential relaxation function. The respective CD and IR spectra are qualitatively different from the canonical spectra of polyproline in aqueous solution, and are indicative of a highly packed state. © 2009 Wiley Periodicals, Inc. Biopolymers 93: 451–457, 2010.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Short-term outcomes with intrathecal versus epidural analgesia in laparoscopic colorectal surgery
Authors: Virlos I , Clements D , Beynon J , Ratnalikar V , Khot U
Published: July 2010

Background

Epidural analgesia is the mainstay of perioperative pain management in enhanced recovery programmes. This study compared short-term outcomes following epidural or intrathecal analgesia in patients undergoing elective laparoscopic colorectal surgery.

Methods

A single-centre observational study was carried out in 175 consecutive patients who had elective laparoscopic colorectal surgery for benign or malignant disease within an enhanced recovery programme. Seventy-six patients received epidural analgesia and 99 had a single injection of intrathecal analgesia to provide perioperative pain control.

Results

Patients who had intrathecal analgesia had a reduced median postoperative pain score compared with those receiving epidural analgesia (0 versus 3·5; P < 0·001), an earlier return to mobility (1 versus 4 days; P < 0·001) and a shorter hospital stay (4 versus 5 days; P < 0·001). Return to normal gut function and postoperative nausea and vomiting were similar in the two groups.

Conclusion

Intrathecal analgesia may have advantages over epidural analgesia in patients undergoing laparoscopic colorectal surgery.
A novel model for web‐based adaptive educational hypermedia systems: SAHM (supervised adaptive hypermedia model)
Authors: Kahraman H. Tolga , Sagiroglu Seref , Colak İlhami
Published: July 2010

Existing adaptive educational hypermedia systems focus on preparing adaptive educational environments for students and educators meeting their needs. In an educational adaptive hypermedia (AH) application, important problems faced by application developers (educators) are to create and update the domain model accurately. This study presents a new reference model and its concept for web‐based adaptive educational hypermedia called SAHM (supervised adaptive hypermedia model). The new model redefines the storage layer of existing AH reference models and helps to solve the problems encountered in AH applications. With the help of this proposed model, application developers might develop a domain model of AH applications easily, effectively, and successfully. It is expected that the new SAHM would provide a new direction in designing new and more adaptive systems and new applications. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 60–74, 2013
A visual toolbox for modeling and testing multi‐net neural systems
Authors: Melin Patricia , Mendoza Olivia , Castillo Oscar , Castro Juan Ramon
Published: July 2010

Neural networks (NN) and muti‐net neural systems are popular and important topics for graduate engineering students. This paper describes a visual toolbox that has been developed to perform experiments with new multi‐net neural structures, including ensemble and modular NN approaches. This toolbox can be considered an important contribution for graduate engineering education and research because it is a complete tool that allows to draw models, set parameters, save projects, and generate files with results in a user friendly visual environment. Experimental results with a group of students after using the toolbox show a significant improvement on the acquired knowledge of NNs concepts. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 164–184, 2013
Community and school choice: Geographies of care and responsibility
Authors: Wilkins Andrew
Published: July 2010

This paper draws on elements of critical discursive psychology in order to explore some of the issues and concerns raised by parents' responses to the policy and practice of school choice. Drawing on data from a group of mothers of diverse social class and racial backgrounds, this paper examines the dilemmas some mothers engage with in their role as chooser—reconciling competing rationalities for choosing or trying to manage contradictions. A central argument of this paper is that the policy and political context shaping the emergence of school choice in Britain has provisionally secured the development of certain trends in education—consumerism, individualism and competition. Alongside and coupled with this has been the veneration of a narrow utilitarian conception of parents as consumers of education services, defined as people who share the capacity and willingness to maximize the utility of their decisions in a rationally self‐interested way. This paper questions the value of this approach as a framing for understanding the aspirations, motivations and fantasies informing parents' school choice and highlights instead the ways in which some mothers articulate the importance of community in their decision‐making practices. Copyright © 2010 John Wiley & Sons, Ltd.
Group identity, ethnic separatism and multiple out‐groups: The Basque case
Authors: Martinovic Borja , Verkuyten Maykel , Weesie Jeroen
Published: July 2010

Within the context of the Basque Country in Spain we examined how ethnic (Basque) and national (Spanish) identification relate to the evaluation of Spaniards, Basques, Andalusians and Catalans. On a sample of adolescent participants we tested a structural equation model which considered identity content (Basque separatism) as a mediator of the relationship between group identifications and group evaluations. While Spanish and Basque identification were associated with a positive evaluation of Spanish and Basque in‐groups, respectively, the evaluation of out‐groups that are relatively similar to the in‐group were not affected by identification. In contrast, dissimilar out‐groups tended to be evaluated more negatively by higher in‐group identifiers. Basque separatism mediated the negative relationship between Basque identification and the evaluation of Spaniards and of Andalusians as a prototypically Spanish subgroup. It is concluded that identification relates differently to the evaluation of different out‐groups, and that the ideological content of identity plays an important role in determining intergroup relations. Copyright © 2010 John Wiley & Sons, Ltd.
The SCAI Structural Heart Disease Council: Toward addressing training, credentialing, and guidelines for structural heart disease intervention
Authors: Feldman Ted , Ruiz Carlos E. , Hijazi Ziyad M.
Published: July 2010

The field of structural heart disease (SHD) intervention has grown rapidly over the past several years. While training program content, standards, credentialing, and board examinations for percutaneous coronary intervention have matured and become well developed, no such structure exists in the field of SHD. Recognition of the need for training program standards and SHD curriculum stimulated the SCAI to form a SHD council, described in this report. In the accompanying two articles, we report the results of a survey of the status of SHD training in programs in the United States and define a core curriculum for structural intervention training. © 2010 Wiley‐Liss, Inc.
Results of the society of cardiac angiography and interventions survey of physicians and training directors on procedures for structural and valvular heart disease
Authors: Herrmann Howard C. , Baxter Sandra , Ruiz Carlos E. , Feldman Ted E. , Hijazi Ziyad M.
Published: July 2010

Background: Minimal information is available on the number and type of procedures being performed for structural and valvular heart disease, the physicians who perform these procedures, and on the training requirements for this emerging field. Methods: Surveys were performed using an online survey of members of the Society of Cardiac Angiography and Interventions (SCAI), including its Council on Structural Heart Disease and the Congenital Heart Disease Committee. The responses of 107 US‐based interventional cardiologists were analyzed. A second questionnaire of a purposive sample of 10 training directors of US interventional cardiology programs was also performed. Results: Although many procedures (e.g., transseptal puncture, PFO, and ASD closure) are commonly performed by most respondents, others are limited to a significant minority of respondents (e.g., alcohol septal ablation, transcatheter valve repair, and implantation). In addition, the number of procedures performed varies greatly as does the training directors' estimate of the number necessary to gain proficiency. There is no single method being used to gain the requisite skills. A number of factors that limit the more widespread growth of this field were identified. Conclusions: The field of intervention for structural and valvular heart disease is new, growing rapidly, and will require a core knowledge base and new didactic methods. The cardiovascular community will be challenged to devise new training standards and credentialing approaches to serve interventionalists interested in this field. © 2010 Wiley‐Liss, Inc.
Premere occlusion system for transcatheter patent foramen ovale closure: Mid‐term results of a single‐center registry
Authors: Rigatelli Gianluca , Cardaioli Paolo , Dell'Avvocata Fabio , Giordan Massimo , Chinaglia Mauro
Published: July 2010

Background: Transcatheter closure of patent foramen ovale (PFO) with rigid devices may be problematic in patients with long channel PFO: alternative devices with asymmetrical opening and more physiological positioning may be preferable in such cases. We present the mid‐term results of transcatheter closure of PFO with Premere Occlusion System, a device studied for this specific anatomy, in a single‐center registry of adults with previous cerebral ischemia. Methods: During a 53‐months period (July 1, 2005 to December 1, 2009) 70 patients (48 females and 22 males, mean age 38 ± 6.7 years) with previous stroke were admitted in our center for transcatheter closure of PFO with Premere Occlusion System on the basis of absence of moderate or severe atrial septal aneurysm (ASA) on Transesophageal echocardiography and intracardiac echocardiography (< 3RL or 3LR ASA and length of PFO channel >10 mm). Results: The procedure was successful in all of the patients with no peri‐operative and in‐hospital complications. Forty‐six 20 mm and twenty‐four 25 mm Premere devices were implanted. Rates of procedural success, predischarge occlusion, and complication were: 100%, 95.7% and 0%, respectively. On mean follow‐up of 40 ± 10.9 months (range 6–54), the follow‐up occlusion rate was 98.5%. During follow‐up, no cases of permanent atrial fibrillation, aortic/atrial erosion, device thrombosis, or atrioventricular valve inferences were noted. Conclusion: The mid‐term outcomes of our registry suggests that the Premere Occlusion System may be an excellent device for patients with long‐channel PFO and absence of moderate/severe ASA, offering a physiological and anatomically respective closure of PFO also in patients with hypertrophic rims. © 2010 Wiley‐Liss, Inc.