bluuebunny/crossref_metadata_2025 huggingface dataset:
Copolymer networks from carboxyl‐containing polyaryletherketone and diglycidyl ether of bisphenol‐A: Preparation and properties
Authors: Liu Fuhua , Wang Zhonggang , Wang Yilong , Zhang Bin
Published: September 2010

This article presents a new type of epoxy‐toughening system, in which high‐Tg polyaryletherketone (PEK‐L) containing one carboxyl group per repeating unit was utilized to randomly copolymerize with epoxy resin (DGEBA) to form crosslinking network. Compared to the neat epoxy resin, the PEK‐L/DGEBA copolymers showed simultaneous enhancement in flexural strains at break by 282%, GIC value by 193%, and flexural strength by 14%. The reason was attributed to the uniform three‐dimensional copolymer network interweaved by PEK‐L and DGEBA segments through strong covalent bonds. The copolymerization process were monitored and examined by FTIR spectra. The effect of copolymer composition on the thermal and mechanical properties as well as toughening mechanism were also investigated and discussed in detail. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2010
Carbon nanotube‐coupled cell adhesion peptides are non‐immunogenic: a promising step toward new biomedical devices
Authors: Gaillard Claire , Duval Monique , Dumortier Hélène , Bianco Alberto
Published: September 2010

Carbon nanotubes functionalized with cell adhesion peptides can be considered as novel, promising candidates for the development of advanced drug delivery systems or for designing new generation of self‐assembling nerve ‘bridges’. An important step toward the integration of these types of conjugates in living bodies is the assessment of their impact on the immune system. In this direction, an integrin‐derived peptide has been covalently conjugated to carbon nanotubes. Following intraperitoneal administration, peptide–carbon nanotubes do not trigger an anti‐peptide antibody production. Demonstration of the immune neutrality of peptide–carbon nanotubes reinforces their potential use as substrates for neuronal regeneration in vivo. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Iterative method based on CFD data for the assessment of seakeeping control effects, considering amplitude and rate saturation
Authors: Giron‐Sierra J. M. , Recas J. , Esteban S.
Published: September 2010

An iterative procedure for the frequency domain evaluation of control effects in nonlinear loops is introduced. The article focuses on ship seakeeping control, to attenuate ship motions. There is no model of the ship, only CFD tabulated data. The proposed procedure could be used for design or empirical tuning of a controller. The actuators have angle and rate limits. In the case of a ship, the actuators are submerged moving wings: flaps, fins and T‐foil. The control evaluation procedure uses a describing function approach. The paper considers amplitude and rate saturation in series. The results are validated with experiments using a scaled ship in a towing tank facility. Copyright © 2010 John Wiley & Sons, Ltd.
Dissipative design of unknown input observers for systems with sector nonlinearities
Authors: Rocha‐Cózatl Edmundo , Moreno Jaime A.
Published: September 2010

In this paper a design method for nonlinear Unknown Input Observers (UIO) for a class of nonlinear systems is proposed. This design is based on a dissipative characterization of the existence conditions for such observers made recently by the authors. The main condition corresponds to an abstract incremental dissipativity property of the plant, which can be made computable by the use of LMI techniques for the considered class of systems. This leads to a constructive design method for nonlinear UIOs. Copyright © 2010 John Wiley & Sons, Ltd.
Cluster‐based modularization of processes recovered from web applications
Authors: Di Francescomarino Chiara , Marchetto Alessandro , Tonella Paolo
Published: September 2010

Web applications are often used to expose business processes implemented as software systems. This paper describes a technique for recovering business processes based on a dynamic analysis of the applications behavior. The technique described here does not require any access to internal software artifacts of the application, such as source code or documentation. An initial process is inferred to by means of the analysis of execution traces, in which the execution of GUI elements such as forms and links is recorded. The recovered process is then abstracted by clustering its elements according to four different criteria: structural, page‐based, dependency‐based and semantical. A case study has been conducted with the aim of evaluating understandability and readability of the reverse engineered processes as well as the clustering techniques used in refining them. Copyright © 2010 John Wiley & Sons, Ltd.
Computational models of analogy
Authors: Gentner Dedre , Forbus Kenneth D.
Published: September 2010

Analogical mapping is a core process in human cognition. A number of valuable computational models of analogy have been created, capturing aspects of how people compare representations, retrieve potential analogs from memory, and learn from the results. In the past 25 years, this area has progressed rapidly, fueled by strong collaboration between psychologists and Artificial Intelligence (AI) scientists, with contributions from linguists and philosophers as well. There is now considerable consensus regarding the constraints governing the mapping process. However, computational models still differ in their focus, with some aimed at capturing the range of analogical phenomena at the cognitive level and others aimed at modeling how analogical processes might be implemented in neural systems. Some recent work has focused on modeling interactions between analogy and other processes, and on modeling analogy as a part of larger cognitive systems. WIREs Cogni Sci 2011 2 266–276 DOI: 10.1002/wcs.105

This article is categorized under:

Computer Science > Artificial Intelligence

Psychology > Reasoning and Decision Making
Ab‐initio Structure Determination of the New Ion Conductor K2Al2O3F2 from Powder Diffraction Data
Authors: Kubel Frank , Fleig Jürgen , Pantazi Mariana , Januschewsky Judith
Published: September 2010

The crystal structure of K2Al2O3F2, prepared at 800 °C by ceramic methods, was determined from conventional laboratory X‐ray powder diffraction data. The compound crystallizes in the monoclinic space group C2/m (No. 12) with a = 11.21675(8), b = 8.16351(6), c = 6.12301(5) Å β = 88.8108(6) ° and Z = 4. Unit cell and space group suggestions were found by using the TOPAS program. Starting positional parameters for potassium and aluminum atoms were obtained from 548 reflections by the methods implemented in the FOX program. Oxygen and fluorine atom positions were determined by structural considerations. The structure was refined using the fundamental parameter approach of TOPAS, which gave the final residuals (%) RBragg = 1.6 and Rwp = 4.6. The crystal structure consists of individual layers of oxygen connected AlO3F tetrahedral groups with the fluorine atoms separating the layers. Empirical energy calculations agree with the crystal structure refinements and suggest no or little oxygen–fluorine exchange. Between and perpendicular to the sheets, the potassium ion can move without steric hindrance. Conductivity measurements from room temperature to 300 °C show decent potassium ion conductivity.
Truncation of subunit ND2 disrupts the threefold symmetry of the antiporter‐like subunits in complex I from higher metazoans
Authors: Birrell James A. , Hirst Judy
Published: September 2010

Three of the conserved, membrane‐bound subunits in NADH:ubiquinone oxidoreductase (complex I) are related to one another, and to Mrp sodium‐proton antiporters. Recent structural analysis of two prokaryotic complexes I revealed that the three subunits each contain fourteen transmembrane helices that overlay in structural alignments: the translocation of three protons may be coordinated by a lateral helix connecting them together (Efremov, R.G., Baradaran, R. and Sazanov, L.A. (2010). The architecture of respiratory complex I. Nature 465, 441–447). Here, we show that in higher metazoans the threefold symmetry is broken by the loss of three helices from subunit ND2; possible implications for the mechanism of proton translocation are discussed.
Human Rights Enforcement by People Living in Poverty: Access to Justice in Nigeria
Authors: Brems Eva , Adekoya Charles Olufemi
Published: September 2010

This article analyses the challenges facing those living in poverty in Nigeria in accessing justice for the enforcement of their rights, despite those rights being constitutionally protected and despite the existence of a specific procedure for their enforcement. People living in poverty are generally most likely to see their human rights violated, and least likely to enforce their rights. The article posits that the judiciary in developing countries has a crucial role to play in fighting human rights violations specifically affecting people living in poverty, and notes the great challenge for the Nigerian legislator and judiciary towards making justice accessible in practical terms to the needy in Nigeria. The example of public interest litigation in India can serve as a source of inspiration in this respect.
The structural basis of function in Cys-loop receptors
Authors: Thompson Andrew J. , Lester Henry A. , Lummis Sarah C. R.
Published: September 2010

Cys-loop receptors are membrane-spanning neurotransmitter-gated ion channels that are responsible for fast excitatory and inhibitory transmission in the peripheral and central nervous systems. The best studied members of the Cys-loop family are nACh, 5-HT3, GABAAand glycine receptors. All these receptors share a common structure of five subunits, pseudo-symmetrically arranged to form a rosette with a central ion-conducting pore. Some are cation selective (e.g. nACh and 5-HT3) and some are anion selective (e.g. GABAAand glycine). Each receptor has an extracellular domain (ECD) that contains the ligand-binding sites, a transmembrane domain (TMD) that allows ions to pass across the membrane, and an intracellular domain (ICD) that plays a role in channel conductance and receptor modulation. Cys-loop receptors are the targets for many currently used clinically relevant drugs (e.g. benzodiazepines and anaesthetics). Understanding the molecular mechanisms of these receptors could therefore provide the catalyst for further development in this field, as well as promoting the development of experimental techniques for other areas of neuroscience.

In this review, we present our current understanding of Cys-loop receptor structure and function. The ECD has been extensively studied. Research in this area has been stimulated in recent years by the publication of high-resolution structures of nACh receptors and related proteins, which have permitted the creation of many Cys loop receptor homology models of this region. Here, using the 5-HT3receptor as a typical member of the family, we describe how homology modelling and ligand docking can provide useful but not definitive information about ligand interactions. We briefly consider some of the many Cys-loop receptors modulators. We discuss the current understanding of the structure of the TMD, and how this links to the ECD to allow channel gating, and consider the roles of the ICD, whose structure is poorly understood. We also describe some of the current methods that are beginning to reveal the differences between different receptor states, and may ultimately show structural details of transitions between them.
Non-real zeros of derivatives of real meromorphic functions of infinite order
Authors: LANGLEY J. K.
Published: September 2010

Let f be a real meromorphic function of infinite order in the plane, with finitely many zeros and non-real poles. Then f″ has infinitely many non-real zeros.
Cardiovascular effects of edible oils: a comparison between four popular edible oils
Authors: Bester D. , Esterhuyse A. J. , Truter E. J. , van Rooyen J.
Published: September 2010

Edible oils form an essential part of the modern diet. These oils play a role as an energy source, and provide the diet with many beneficial micronutrients. Although a popular conception may be that fat should be avoided, certain edible oils as a dietary supplement may play an important role in the improvement of cardiovascular health. CVD has become one of the leading causes of death worldwide. Dietary supplementation with different oils may have beneficial effects on cardiovascular health. While olive oil and sunflower-seed oil are known to reduce serum cholesterol, fish oil has become well known for reducing potentially fatal cardiac arrhythmias. Recently, red palm oil research has shown beneficial effects on cardiac recovery from ischaemia–reperfusion injury. It is clear that dietary supplementation with edible oils may play a vital role in reducing the mortality rate due to heart disease. The specific benefits and disadvantages of these oils should, however, be explored in greater depth. The present review will attempt to identify the benefits and shortcomings of four popular edible oils, namely olive oil, sunflower-seed oil, fish oil and palm oil. Additionally the present review will aim to reveal potential areas of research which could further enhance our understanding of the effects of edible oils on cardiovascular health.
Stroke thrombolysis in the very elderly
Authors: McGreevy Cora , Moore Alan , Donegan Ciaran , Williams David JP
Published: September 2010

Acute ischaemic stroke is common in older people and is associated with a higher morbidity and mortality compared with younger patients. Intravenous thrombolysis with recombinant tissue plasminogen activator (r-tPA) has become the mainstay of treatment and is the only evidence-based specific treatment for acute ischaemic stroke. However, little data are available on the safety of thrombolysis in the over-80 years age group due to under-representation of this group in trials and the upper age limit for licensing of the drug. In this review, we look at the pathophysiology of stroke and recent advances in neuroimaging techniques. We also look at the evidence base for use of thrombolysis in stroke and in particular analyse the trials that include the very elderly as subjects. Finally, issues around ongoing trials and future research are discussed.
JOB COMPETITION, CROWDING OUT, AND UNEMPLOYMENT FLUCTUATIONS
Authors: Khalifa Sherif
Published: September 2010

This paper attempts to determine the factors generating the persistence of unemployment over the business cycle. The observations show that the total unemployment rate is highly persistent, and that the persistence of the unemployment rate of unskilled workers is higher than that of skilled workers. To account for these observations, the paper develops a framework that features search frictions. Individuals are either high educated or low educated, and firms post two types of vacancies: the complex, which can be matched with the high educated, and the simple, which can be matched with the high and the low educated. On-the-job search for a complex occupation is undertaken by the high educated in simple occupations. A negative aggregate technological shock induces the high educated unemployed to compete with the low educated by increasing their search intensity for simple vacancies. As the high educated occupy simple vacancies, they crowd out the low educated into unemployment. This downgrading of jobs in a cyclical downturn, or the increase in the labor input of the high educated in simple occupations, and the subsequent crowding out of the low educated into unemployment, provide a possible explanation for unemployment persistence.
Hispanic consumers' perceptions toward locally grown ethnic produce: A study from the east-coast US
Authors: Govindasamy Ramu , Puduri Venkata S.
Published: September 2010

The purpose of this study was to predict Hispanic consumer's willingness to buy ethnic produce grown on local farms. Specifically, this result analyzes and compares the effects of Hispanic consumers' socio-economic characteristics and their expressed value judgments on their willingness to buy locally grown ethnic fruits and vegetables. The survey instrument asked respondents whether they were willing to buy ethnic produce grown on local farms, and based on this, an ordered probit model was developed to predict the willingness to buy ethnic produce grown on local farms. The model has significant explanatory power with 80% overall model prediction success. According to the survey results, overall, 80% of the Hispanic respondents were willing to buy locally grown ethnic produce, 13% of them were indifferent and only 7% of them were less willing to buy. The high positive percentage indicates the intensity of consumers' interest toward willing to buy locally grown produce. The study results indicated that growing demand for Hispanic ethnic produce provides a potential opportunity for farmers in the region.
Increasing the Gender Diversity of High Courts: A Comparative View
Authors: Hoekstra Valerie
Published: September 2010

The appointment of Sonia Sotomayor and the nomination of Elena Kagan to the United States Supreme Court provides a timely opportunity for scholars, policymakers, and members of the legal community to consider why there are so few women on the world's highest courts. Although singular moments draw our attention to the importance of women on high courts, sadly, this attention is rarely sustained over long periods. While much was made of Ronald Reagan's historic nomination of Sandra Day O'Connor to serve as the first female justice of the U.S. Supreme Court, more than a decade and four nomination opportunities passed by before Ruth Bader Ginsburg was appointed. On this point, Paula Monopoli aptly observes: “[T]he assumption that progress would steadily continue until gender parity was achieved has proven to be wrong” (2007, 43). Unfortunately, this same observation could be said of virtually all other high courts across the globe.
Judging Alone: Reflections on the Importance of Women on the Court
Authors: O'Connor Karen , Yanus Alixandra B.
Published: September 2010

“The word I would use to describe my position on the bench is lonely.” So said Justice Ruth Bader Ginsburg in 2007, when asked to comment on her position on the U.S. Supreme Court after the resignation of Justice Sandra Day O'Connor. After a year as the Court's only woman, Ginsburg had begun to feel the solitude that comes from judging alone, being the Court's only descriptive and often symbolic representative of women's interests. Ginsburg's position was not, sadly, as rare as we might hope in industrialized democracies. Although some countries, such as Canada, have had near majorities of women on their respective high courts, other countries, such as the United Kingdom, continue to have only one woman on their national tribunals.
Critical Perspectives on Gender and Judging
Authors: Kenney Sally J.
Published: September 2010

I began to write this essay as confirmation hearings opened for President Barack Obama's nominee for the U.S. Supreme Court, Judge Sonia Sotomayor, and long before he nominated Elena Kagan. The nominations have made the gender and ethnic identities of judges and senators alike salient. In their opening statements, senators burst with pride about a great country where anyone can achieve anything, regardless of gender, class, or ethnicity, while some equated empathy with prejudice and difference with partiality. In aNew York Times Magazineinterview the Sunday before, Justice Ruth Bader Ginsburg stressed the importance of more women on the bench (Bazelon 2009). Opponents' carefully orchestrated media attacks against Sotomayor, arguing that she lacked judicial temperament (too mean) and was racist, came straight from the misogynist playbook well thumbed from Hillary Clinton's presidential campaign. I share Nancy Maveety's disappointment that the hearings squelched, rather than explored, the questions of what Martha Minow (1987) has so aptly named “the dilemma of difference”—how women can be both equal to and different from men—and the nature of judging, which has to do with how one's social location and life experiences inevitably shape judgment. The dullness of the actual hearings stood in sharp contrast to the euphoria in the Latino community where many sported the latest fashion: “Wise Latina Woman” T-shirts, dispelling any doubt about the symbolic importance of such appointments.
Seismic source mechanism of degassing bursts at Kilauea Volcano, Hawaii: Results from waveform inversion in the 10–50 s band
Authors: Chouet Bernard A. , Dawson Phillip B. , James Mike R. , Lane Stephen J.
Published: September 2010

The current (March 2008 to February 2009) summit eruptive activity at Kilauea Volcano is characterized by explosive degassing bursts accompanied by very long period (VLP) seismic signals. We model the source mechanisms of VLP signals in the 10–50 s band using data recorded for 15 bursts with a 10‐station broadband network deployed in the summit caldera. To determine the source centroid location and source mechanism, we minimize the residual error between data and synthetics calculated by the finite difference method for a point source embedded in a homogeneous medium that takes topography into account. The VLP signals associated with the bursts originate in a source region ∼1 km below the eastern perimeter of Halemaumau pit crater. The observed waveforms are well explained by the combination of a volumetric component and a vertical single force component. For the volumetric component, several source geometries are obtained which equally explain the observed waveforms. These geometries include (1) a pipe dipping 64° to the northeast; (2) two intersecting cracks including an east striking crack (dike) dipping 80° to the north, intersecting a north striking crack (another dike) dipping 65° to the east; (3) a pipe dipping 58° to the northeast, intersecting a crack dipping 48° to the west–southwest; and (4) a pipe dipping 57° to the northeast, intersecting a pipe dipping 58° to the west–southwest. Using the dual‐crack model as reference, the largest volume change obtained among the 15 bursts is ∼24,400 m3, and the maximum amplitude (peak to peak) of the force is ∼20 GN. Each burst is marked by a similar sequence of deflation and inflation, trailed by decaying oscillations of the volumetric source. The vertical force is initially upward, synchronous with source deflation, then downward, synchronous with source reinflation, followed by oscillations with polarity opposite to the volumetric oscillations. This combination of force and volume change is attributed to pressure and momentum changes induced during a fluid dynamic source mechanism involving the ascent, expansion, and burst of a large slug of gas within the upper ∼150 m of the magma conduit. As the slug expands upon approach to the surface and more liquid becomes wall supported by viscous shear forces, the pressure below the slug decreases, inducing conduit deflation and an upward force on the Earth. The final rapid slug expansion and burst stimulate VLP and LP oscillations of the conduit system, which slowly decay due to viscous dissipation and elastic radiation. Consideration of the fluid dynamic arguments leads us to prefer the dual‐crack VLP source model as it is the only candidate model capable of producing plausible values of length scales and pressure changes. The magnitudes of the vertical forces observed in the 15 bursts appear consistent with slug masses of 104 to 106 kg.
Emergency use of groundwater as a backup supply: Quantifying hydraulic impacts and economic benefits
Authors: Reichard Eric G. , Li Zhen , Hermans Caroline
Published: September 2010

Groundwater can play an important role in water‐supply emergency planning. A framework is presented for assessing the hydraulic impacts and associated costs of using groundwater as a backup supply when imported‐water deliveries are disrupted, and for quantifying the emergency benefits of groundwater management strategies that enable better response to such disruptions. Response functions are derived, which relate additional groundwater pumpage during water‐supply emergencies to impacts such as increased pumping costs, subsidence, and seawater intrusion. Monte Carlo analysis is employed to estimate the incremental costs of using groundwater as a backup supply. The emergency benefits of alternative groundwater management strategies are computed for different expected durations of imported water disruption, percentages of imported water replaced by groundwater, and threshold drawdowns for subsidence impacts. The methodology is applied to the coastal Los Angeles Basin. For this case study, emergency benefits of artificial recharge strategies are dominated by reduction of potential subsidence costs. The variance of the results also is primarily due to subsidence effects. Incorporation of probability distributions reflecting a larger expected use of groundwater during the imported‐water disruption results in higher estimated emergency benefits of artificial recharge strategies. The framework presented for quantifying incremental costs and economic benefits of using groundwater as a backup supply could be applied to a broad range of water emergency planning decisions.
In situ evaluation of the initiation of the North Atlantic phytoplankton bloom
Authors: Boss E. , Behrenfeld M.
Published: September 2010

Two years of continuous physical and optical measurements from a profiling float in the western subarctic North Atlantic are used to analyze seasonal phytoplankton dynamics. The observed annual cycle challenges the traditional view that initiation of spring accumulations of phytoplankton in the upper water column requires a critical stratification threshold (known as the ‘Gran effect’ or the ‘Sverdrup Hypothesis’). Instead, we find that biomass accumulation begins in mid‐winter when light levels are minimal and near‐surface mixing is deepest. These observations are consistent with the recently proposed dilution–recoupling hypothesis which states that deep winter mixing in the North Atlantic is essential for bloom formation as it decouples phytoplankton growth from grazing losses, thereby allowing net biomass accumulation despite low‐light conditions.
Characterization of the electric potential distribution and large scale auroral zone flows in the ionosphere
Authors: Keating C. F. , Heelis R. A.
Published: September 2010

In this investigation, we examine the latitude distribution of convective F region ion drifts at latitudes below the convection reversal boundary. We express latitude variations in terms of an electrostatic potential distribution to determine the sensitivity to interplanetary conditions, magnetic activity, and local time. We use a Gaussian curve segment to best represent the distribution of the potential equatorward of the polar cap and find the Gaussian half width is dependent on the potential at the convection reversal boundary with the half width being larger on the duskside than on the dawnside. We also find this parameter is dependent on local time as well as Kp. In all cases, the half width shows a greater variability on the duskside than on the dawnside.
Equatorial Atlantic interannual variability: Role of heat content
Authors: Ding Hui , Keenlyside Noel S. , Latif Mojib
Published: September 2010

The dynamics of the equatorial Atlantic zonal mode are studied using observed sea surface height (SSH), sea surface temperature (SST), and heat flux and reanalysis wind stress and upper ocean temperature. Principal oscillation pattern (POP) analysis shows that the zonal mode is an oscillatory normal mode of the observed coupled system, obeying the delayed action/recharge oscillator paradigm for El Niño Southern Oscillation. Variations in equatorial averaged SSH, a proxy for upper ocean heat content, precede SST anomalies in the cold tongue by 4–5 months, about a quarter of the POP period. Positive subsurface temperature anomalies appear in the west, as a delayed response to the preceding cold event. These propagate eastward, where due to the shallow thermocline they can influence SST, leading to the next warm event. Although SST variations exhibit weak westward propagation during some zonal mode events, POP analysis indicates that to first order there is no zonal propagation in SST. Net surface heat flux anomalies generally act to damp SST anomalies. The zonal mode explains a large amount (70%) of SST variability in the east and a significant fraction (19%) of equatorial variability. Thus, the predictability potential in the equatorial Atlantic on seasonal time scales may be considerably higher than currently thought.
Spin-wave resonances in exchange-coupled Permalloy/garnet bilayers
Authors: Ben Youssef J. , Castel V. , Vukadinovic N. , Labrune M.
Published: September 2010

Exchange coupling at the interface between a single-crystal garnet film with a perpendicular anisotropy and a Permalloy film with an in-plane anisotropy was investigated both experimentally and theoretically. Wide-band (2–20 GHz) ferromagnetic resonance measurements in parallel configuration reveal spectra with multiple resonance lines (up to four). These data were analyzed by means of a standing spin-wave model extended to account for in-plane/out-of-plane anisotropy bilayers and to include a finite value of the bilinear interfacial exchange coupling J. The field and frequency evolutions of the observed multiple resonance peaks were satisfactorily reproduced using the value J=0.18±0.05 erg/cm2.
Model core potentials of p-block elements generated considering the Douglas–Kroll relativistic effects, suitable for accurate spin-orbit coupling calculations
Authors: Zeng Tao , Fedorov Dmitri G. , Klobukowski Mariusz
Published: September 2010

Model core potentials with scalar-relativistic effect at the third order Douglas–Kroll level combined with the first-order Douglas–Kroll for spin-orbit coupling are developed for the 25 p-block elements, B-Tl, with the valence space starting at (n−1)p(n−1)d, except group 13, where (n−1)s is also included because its importance was clearly demonstrated for Tl. All of the comparisons between model core potential and all-electron calculations of atomic and ionic term and level energies and the spectroscopic constants of monohydrides and cationic dimers indicate the chemical accuracy of our new potentials in reproducing all-electron properties. The applications of the new potentials to the cationic dimers show that polyatomic calculations with model core potential atoms are accurate. The periodic trends in the spectroscopic properties of cationic dimers and hydrides are discussed. The timing study demonstrates the extent of the computational savings. These new sets of model core potentials and basis sets, which we call ZFKn-DK3, have been implemented in the the widely used quantum chemistry program package GAMESS-U.S.
Fabrication and characterization of the multiferroic birelaxor lead–iron–tungstate/lead–zirconate–titanate
Authors: Kumar Ashok , Katiyar R. S. , Scott J. F.
Published: September 2010

We compare chemical solution deposition (CSD) and pulsed laser deposition (PLD), specimens of the room temperature, single-phase, multiferroic magnetoelectric, [PbFe0.67W0.33O3]x[PbZr0.53Ti0.47O3]1−x (PZTFWx∼0.40<x<0.20) with high polarization, low loss (∼2%–5%), and high resistivity (typically 108 Ω cm). Single phase polycrystalline multiferroics PZTFWx thin films were fabricated on platinized silicon substrate by CSD and as epitaxial single-crystal films on MgO (100) substrate by PLD. PLD grown samples showed high dielectric constants (1200–3000), high polarization (30–60 μC/cm2), and weak saturation magnetization (2.11–5.47 emu/cm3) compare to the dielectric constants (800–1400), polarization (11–22 μC/cm2), and magnetization (0.48–4.53 emu/cm3) of CSD grown films, where as a broad dielectric temperature peak, high-frequency dispersion, low dielectric loss, and low leakage current were observed in these materials synthesized by both methods, suggesting the family as candidates for room temperature multiferroic devices. The ferroelectric switching in these materials can be suppressed or quenched with applied magnetic field.
Resistance switching at the interface of LaAlO3/SrTiO3
Authors: Chen Y. Z. , Zhao J. L. , Sun J. R. , Pryds N. , Shen B. G.
Published: September 2010

At the interface of LaAlO3/SrTiO3 with film thickness of 3 unit cells or greater, a reproducible electric-field-induced bipolar resistance switching of the interfacial conduction is observed on nanometer scale by a biased conducting atomic force microscopy under vacuum environment. The switching behavior is suggested to be an intrinsic feature of the SrTiO3 single crystal substrates, which mainly originates from the modulation of oxygen ion transfer in SrTiO3 surface by external electric field in the vicinity of interface, whereas the LaAlO3 film acts as a barrier layer.
The Missing Link between Technological Standards and Value-Chain Governance: The Case of Patent-Distribution Strategies in the Mobile-Communication Industry
Authors: Wen Hu , Yang Daniel You-Ren
Published: September 2010

In this paper we explore the effects of technological standards on the governance structure of production networks by investigating patent-distribution strategies in the global mobile-communication industry. Through a comparative analysis of two mobile-communication technology standards—GSM and CDMA—we find that there exist significantly different patent-distribution strategies which result in varied governance structure as well as power relations within seemingly similar production networks. Furthermore, the different social–institutional processes of standard setting and implementation of GSM and CDMA contribute to this varied governance structure to a significant degree. Thus, we highlight the role of patent-distribution strategies in influencing value-chain governance, and provide a dynamic view of technological standards.
The Living Conditions Diamond: An Analytical and Theoretical Framework for Understanding Slums
Authors: Gulyani Sumila , Bassett Ellen M
Published: September 2010

What constitutes a ‘slum’ is much debated in the urban poverty and affordable housing literature. We argue that a focus on living conditions can help clarify this and present a framework, the living conditions diamond, for detailing living conditions and determining how the settlements we deem ‘slums’ compare with each other and with nonslum settlements. The diamond distils living conditions into four dimensions: (i) tenure, (ii) infrastructure, (iii) unit quality, and (iv) neighbourhood and location. This framework depicts conditions in graphic terms enabling comparison of conditions within and across cities. The diamond moves us beyond the notion that slums are homogeneously poor in quality, and facilitates analyses that can reveal why they differ. Settlements in Nairobi, Kenya and Dakar, Senegal are compared.
Using Geodemographics to Measure and Explain Social and Environment Differences in Road Traffic Accident Risk
Authors: Anderson Tessa K
Published: September 2010

Geodemographic systems currently provide classifications of small areas based primarily on their demographic and socioeconomic characteristics. This paper presents an innovative use of geodemographic methods in the public sector, in particular to determine people's road injury risk. It uses Stats19 road accident data from the London Metropolitan Police, specifically postcode information relating to the driver and casualty of each road accident from 1999 to 2003. Experian's Mosaic software was used to append each postcode to a geodemographic Mosaic type. The results showed distinct spatial and statistical prevalence of certain groups within society to be more at risk of being in a road accident. This highlights the need for a more sophisticated understanding of the different risks people face as they engage in the road environment.
ATTACHMENT TO EUROPE AMONG SCHOOL LEADERS IN BERLIN AND LONDON
Authors: Pöllmann Andreas
Published: September 2010

Comparisons of public opinion in England and Germany consistently show higher levels of attachment to Europe and support for European integration in Germany. The respective cross-national differences are empirically well-documented, can be framed in plausible macro-contextual explanations, and are – on the descriptive level – confirmed in the present survey of Berlin and London state secondary school head teachers. However, in view of such conclusive evidence, it is easy to overlook cross-national convergences pertaining to people's individual experiences and perceptions. This article offers an alternative view on empirically well-documented and theoretically plausible cross-national differences in levels of attachment to Europe, with a particular interest in the field of formal education. Drawing on a series of multivariate statistical analyses, it demonstrates that – in Berlin as well as in London – levels of attachment to Europe largely depend on the head teachers' intercultural experiences and skills as well as their notions of Europe as object of attachment. The respective findings lend support to educational programmes and initiatives that promote intercultural experiences and skills as means towards further European integration.
Functional Characterization of fst1 in Fusarium verticillioides During Colonization of Maize Kernels
Authors: Kim Hun , Woloshuk Charles P.
Published: September 2010

The putative hexose transporter gene fst1 in Fusarium verticillioides was identified previously by microarray analysis as a gene that was more highly expressed during colonization of autoclaved maize endosperm than germ. In contrast to a previous study, in which disruption of fst1 did not affect growth of the pathogen on autoclaved maize kernels, in the current study, we demonstrated that disruption of fst1 delayed growth and symptom development on wounded maize ears. Characterization of the fst1 promoter revealed that regulation of fst1 expression was similar to that of fumonisin biosynthetic (fum) genes; expression was highest during growth on endosperm tissue and repressed by elevated concentrations of ammonium in the growth medium. With a fluorescent tag attached to FST1, the protein localized transiently to the periphery of the cells near the plasma membrane and in vacuole-like structures, suggesting that membrane-localized FST1 was internalized and degraded in vacuoles. Expression of fst1 in a yeast strain lacking hexose transporter genes did not complement the yeast mutation, suggesting that FST1 does not transport glucose, fructose, or mannose. The results indicate a functional role for FST1 in pathogenesis during the colonization of living kernels.
First Report of Grapevine leafroll-associated virus 5 in Spain
Authors: Padilla C. V. , Cretazzo E. , Hita I. , López N. , Padilla V. , Velasco L.
Published: September 2010

Grapevine leafroll-associated viruses (GLRaVs) cause significant reductions in yield and quality in the wine industry worldwide. At least nine different GLRaVs have been found in different regions of the world. In the process of virus indexing of candidate grapevine clones for certification, which includes grafting of scions onto rootstocks, we observed strong leafroll symptoms 1 year after grafting with one vine of cv. Estaladina in Castilla y León, Spain and one vine of cv. Tempranillo in La Rioja, Spain, collected in 2008 and 2007, respectively. Both vines tested positive by real-time reverse transcription (RT)-PCR with TaqMan probes specific for Grapevine leafroll-associated virus 5 and double-antibody sandwich (DAS)-ELISA with a mix of monoclonal antibodies that recognizes GLRaV-4, 5, 6, 7, and 9 (Bioreba, Reinach, Switzerland). RNA extracts of both GLRaV-5 positive vines were analyzed by conventional RT-PCR with a pair of consensus degenerated primers derived from GLRaV-5 hsp70 sequences available in GenBank: LR5HYF (5′-TGGGATGAAYAARTTCAATGC-3′) and LR5HYR (5′-TGAAATTCCTCATRTARGAGC-3′) that amplified a 250-bp fragment. Amplicons were cloned and the comparison of the amino acid sequences (Estaladina isolate, Est110: Accession No. HM208622; Tempranillo isolate, Tem020: Accession No. HM208618) showed in the case of the Est110 isolate, 100 and 82.6% identity, respectively, with the homologous genes of one GLRaV-5 isolate from the United States (AF233934 [3]) and Argentina (EU815935 [2]). For isolate Tem020, the hsp70 gene showed 97.1 and 81.2% amino acid identity with the homologous hsp70 genes of the United States and Argentina isolates. The coat protein (cp) genes of both isolates were also amplified and cloned using the specific GLRaV-5 primers, LR53413 (5′-CGTGATACAAGGTAGGACAACCGT-3′) and LR53843 (5′-CTTGCACTATCGCTGCCGTGAAT-3′), designed according to the sequence of AF233934. Fragments were of the expected size (430 bp) and the nucleotide sequences were obtained (Est110: Accession No. HM363522; Tem020: Accession No. HM363523) and used for pairwise nucleotide comparisons. The Est110 isolate showed 96.7 and 97.5% amino acid identity with the isolates from the United States and Argentina, respectively, while the Tem020 isolate showed 94.8 and 95.6% identity, respectively. Amino acid identity of Est110 and Tem020 cp genes was 100% when compared with the homologous genes of isolates AF233934 and EU815935. To our knowledge this is the first report of GRLaV-5 in Spain. Since 2008, we have detected eight additional vines positive for this virus in 200 clones analyzed for certification, suggesting that the incidence of GLRaV-5 in Spain could be widespread. This research indicates that virus indexing for GLRaV should be included in certification schemes for grapevine candidate clones (1) in Spain.

References: (1) Anonymous. OEPP/EPPO Bull. 38:422, 2008. (2) S. Gomez Talquenca et al. Virus Genes 38:184, 2009. (3) F. Osman et al. J. Virol. Methods 141:22, 2007.
Tribological advancements for reliable wind turbine performance
Authors: Kotzalas Michael N. , Doll Gary L.
Published: September 2010

Wind turbines have had various limitations to their mechanical system reliability owing to tribological problems over the past few decades. While several studies show that turbines are becoming more reliable, it is still not at an overall acceptable level to the operators based on their current business models. Data show that the electrical components are the most problematic; however, the parts are small, thus easy and inexpensive to replace in the nacelle, on top of the tower. It is the tribological issues that receive the most attention as they have higher costs associated with repair or replacement. These include the blade pitch systems, nacelle yaw systems, main shaft bearings, gearboxes and generator bearings, which are the focus of this review paper. The major tribological issues in wind turbines and the technological developments to understand and solve them are discussed within. The study starts with an overview of fretting corrosion, rolling contact fatigue, and frictional torque of the blade pitch and nacelle yaw bearings, and references to some of the recent design approaches applied to solve them. Also included is a brief overview into lubricant contamination issues in the gearbox and electric current discharge or arcing damage of the generator bearings. The primary focus of this review is the detailed examination of main shaft spherical roller bearing micropitting and gearbox bearing scuffing, micropitting and the newer phenomenon of white-etch area flaking. The main shaft and gearbox are integrally related and are the most commonly referred to items involving expensive repair costs and downtime. As such, the latest research and developments related to the cause of the wear and damage modes and the technologies used or proposed to solve them are presented.
Shark-skin surfaces for fluid-drag reduction in turbulent flow: a review
Authors: Dean Brian , Bhushan Bharat
Published: September 2010

The skin of fast-swimming sharks exhibits riblet structures aligned in the direction of flow that are known to reduce skin friction drag in the turbulent-flow regime. Structures have been fabricated for study and application that replicate and improve upon the natural shape of the shark-skin riblets, providing a maximum drag reduction of nearly 10 per cent. Mechanisms of fluid drag in turbulent flow and riblet-drag reduction theories from experiment and simulation are discussed. A review of riblet-performance studies is given, and optimal riblet geometries are defined. A survey of studies experimenting with riblet-topped shark-scale replicas is also given. A method for selecting optimal riblet dimensions based on fluid-flow characteristics is detailed, and current manufacturing techniques are outlined. Due to the presence of small amounts of mucus on the skin of a shark, it is expected that the localized application of hydrophobic materials will alter the flow field around the riblets in some way beneficial to the goals of increased drag reduction.
The rose petal effect and the modes of superhydrophobicity
Authors: Bhushan Bharat , Nosonovsky Michael
Published: September 2010

The wetting of rough surfaces remains a subject of active investigation by scientists. The contact angle (CA) is a traditional parameter used to characterize the hydrophobicity/philicity of a solid surface. However, it was found recently that high CAs can coexist with strong adhesion between water and a solid surface in the case of the so-called ‘rose petal effect’. Several additional parameters have been proposed to characterize the interaction of water with a rough solid surface, including the CA hysteresis, the ability of water droplets to bounce off a solid surface, the tilt angle needed to initiate the flow of a droplet, and the normal and shear adhesion. It is clear now that wetting is not characterized by a single parameter, since several modes or regimes of wetting of a rough surface can exist, including the Wenzel, Cassie, lotus and petal. Understanding the wetting of rough surfaces is important in order to design non-adhesive surfaces for various applications.
Hominin diversity in the Middle Pliocene of eastern Africa: the maxilla of KNM-WT 40000
Authors: Spoor Fred , Leakey Meave G. , Leakey Louise N.
Published: September 2010

The 3.5-Myr-old hominin cranium KNM-WT 40000 from Lomekwi, west of Lake Turkana, has been assigned to a new hominin genus and species,
Kenyanthropus platyops
, on the basis of a unique combination of derived facial and primitive neurocranial features. Central to the diagnosis of
K. platyops
is the morphology of the maxilla, characterized by a flat and relatively orthognathic subnasal region, anteriorly placed zygomatic processes and small molars. To study this morphology in more detail, we compare the maxillae of African Plio-Pleistocene hominin fossils and samples of modern humans, chimpanzees and gorillas, using conventional and geometric morphometric methods. Computed tomography scans and detailed preparation of the KNM-WT 40000 maxilla enable comprehensive assessment of post-mortem changes, so that landmark data characterizing the morphology can be corrected for distortion. Based on a substantially larger comparative sample than previously available, the results of statistical analyses show that KNM-WT 40000 is indeed significantly different from and falls outside the known range of variation of species of
Australopithecus
and
Paranthropus
, contemporary
Australopithecus afarensis
in particular. These results support the attribution of KNM-WT 40000 to a separate species and the notion that hominin taxonomic diversity in Africa extends back well into the Middle Pliocene.