bluuebunny/crossref_metadata_2025 huggingface dataset:
Optical absorption enhancement of embedded Ag nanoparticles with ZnO nanorod arrays
Authors: Ko Yeong Hwan , Yu Jae Su
Published: September 2011

We report the enhancement in optical absorption of embedded silver (Ag) nanoparticles (NPs), which are self‐assembled from Ag films with different thicknesses by a rapid thermal annealing treatment, with zinc oxide (ZnO) nanorod arrays (NRAs) on fluorine‐doped SnO2/glass by a simple wet‐chemical synthesis using a thin sputtered ZnO seed layer. The optical absorption and photoluminescence (PL) emission are enhanced by the resonant coupling between the localized surface plasmons of Ag NPs. For optimized ZnO NRAs with embedded Ag NPs, the PL peak intensity is increased up to 4.1 times and the optical absorption of Ag NPs is maximized with dipole and quadrupole resonance peaks.
Generation of an electromotive force by hydrogen‐to‐water oxidation with Pt‐coated oxidized titanium foils
Authors: Schierbaum Klaus , El Achhab Mhamed
Published: September 2011

We show that chemically induced current densities up to 20 mA cm−2 and an electromotive force (EMF) up to 465 mV are generated during the hydrogen‐to‐water‐oxidation over Pt/TiO2/Ti devices. We prepare the samples by plasma electrolytic oxidation (PEO) of titanium foils and deposition of Pt contact paste. This process yields porous structures and, depending on the anodization voltage, Schottky diode‐type current–voltage curves of various ideality parameters. Our experiments demonstrate that Pt coated anodized titanium can also be utilized as hydrogen sensor; the system offers a number of advantages such as a wide temperature range of operation from −40 to 80 °C, quick response and decay times of signals, and good electrical stability.

Idealized sketch of the Pt coated anodized Ti foil and application as hydrogen sensor and electric generator.

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Transmission of terahertz radiation by anisotropic MWCNT/polystyrene composite films
Authors: Okotrub A. V. , Kubarev V. V. , Kanygin M. A. , Sedelnikova O. V. , Bulusheva L. G.
Published: September 2011

Anisotropic composite materials have been prepared by repeated forge rolling of polystyrene and carbon nanotubes (CNTs) with length of ∼65 µm. Transmission spectra of the composites were recorded for two different polarizations of the electric field. Obtained data indicated that the forge rolling resulted in a predominant orientation of CNTs in polymer matrix. Anisotropic response of the composites was measured at 130 µm wavelength on the Novosibirsk terahertz free electron laser and angular dependence of the transmitted light was determined. Absorption spectrum showed no strong resonance features and it was interpreted by CNTs breaking and agglomeration of CNT fragments during the composite fabrication procedure. Based on classical theory of scattering, considered the scatters as electromagnetic antennas, the size distribution of CNTs in composites was found.

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Anisotropy of terahertz radiation transmitted from MWCNT/polystyrene composite film on the Novosibirsk free electron laser at 130 µm wavelength.
Ferromagnetic coupling in Mg‐doped passivated AlN nanowires: A first‐principles study
Authors: Tang Zhen‐Kun , Wang Ling‐Ling , Tang Li‐Ming , Li Xiao‐Fei , Xiao Wen‐Zhi , Xu Liang , Zhao Li‐Hua
Published: September 2011

Based on density functional theory calculations, we have studied the electronic structures and magnetic properties of passivated AlN nanowires (NWs) with Mg dopants. The calculated results show that double Mg atom doped passivated AlN NWs display ferromagnetic properties, and the total magnetic moment is 1.80 µB per 96‐atom unit cell excluding the pseudohydrogen atoms. However, a couple of Mg atom doped bare AlN nanowire unit cells display anti‐ferromagnetic (AFM) properties. Unequal properties of magnetic coupling in different Mg‐doped AlN structures are due to the different localization and overlapping of impurity wave functions. It is also found that the ferromagnetic stability and Curie temperature of the passivated AlN NWs are much higher than those of bulk structures.
Effect of Co doping at the B‐site on the structure and transport properties in La2/3Ca1/3MnO3
Authors: Zhang A. M. , Wu X. S. , Bian Q.
Published: September 2011

Polycrystalline samples La2/3Ca1/3(Mn1‐xCox)O3 with x=0.1, 0.2, 0.3, 0.4, and 0.5 were synthesized by standard solid‐state reaction. X‐ray diffraction results show that they are of single phase for the specimens with x≤0.3. Rietveld refinement of X‐ray diffraction data shows Mn‐O‐Mn angle decreases from 178.8° for x=0.1 to 128.8° for x=0.3. A metal‐to‐insulator transition was observed only in sample with x=0.1. The different transport properties of these samples were attributed to the different Jahn‐Teller distortion effect. The temperature dependence of resistivity at low and high temperature can be described by the small polaron model and Kondo‐like effect (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
X‐ray reciprocal space mapping study on semipolar InAlN films coherently grown on ZnO substrates
Authors: Kajima Tomofumi , Kobayashi Atsushi , Shimomoto Kazuma , Ueno Kohei , Fujii Tomoaki , Ohta Jitsuo , Fujioka Hiroshi , Oshima Masaharu
Published: September 2011

We have grown semipolar InAlN films on nearly lattice‐matched ZnO $(1\bar 101)$ substrates and investigated their structural properties. Symmetric and asymmetric reciprocal space‐mapping measurements have revealed that semipolar InAlN films grow coherently on ZnO $(1\bar 101)$ at room temperature. The narrow width of the X‐ray rocking curves and the suppression of tilting of semipolar films can be attributed to this coherency. This forms a striking contrast with the case of semipolar AlN films grown on ZnO. We calculated In composition and lattice strain in the semipolar InAlN films based on a model for the lattice distortion of semipolar wurtzite crystal, and found that In0.26Al0.74N $(1\bar 101)$ grows on ZnO substrates with small lattice strains of less than 1%. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Genus Broussonetia: A Review of its Phytochemistry and Pharmacology
Authors: Wang Guo‐Wei , Huang Bao‐Kang , Qin Lu‐Ping
Published: September 2011

Plants belonging to the genus Broussonetia (Moraceae), which grow naturally in Asian and Pacific countries, have long been used in traditional Chinese medicine to treat various conditions, particularly tinea, dysentery, hernia and oedema. Various parts of plants of this genus such as the fruits, bark, leaves, flowers and roots are used medicinally. According to Flora of China, the inner bark fibre is used in making paper, and the wood is used for furniture. Several active compounds including coumarins, polyphenols, alkaloids, flavonoids, glycosides, lignans and diterpenes have been isolated from the plants of this genus in the past few years, and some members of these constituents have been demonstrated to exert antioxidant, antiinflammatory, antiplatelet, antityrosinase, antimicrobial and antinociceptive effects. Antidiabetic and antitumoural properties seem possible, but need further support. Due to the lack of clinical trials, there are few published reports on target‐organ toxicity or side effects. Currently, some East Asian nations such as China, South Korea and Japan have shown increased interest in these plants. This article reviews the phytochemical and potential beneficial therapeutic effects of plants of this genus reported since 2000. Copyright © 2011 John Wiley & Sons, Ltd.
Vibration Testing of Intermediate Bulk Containers for Dangerous Goods
Authors: Schurig Michael , Klinger Christian
Published: September 2011

Intermediate bulk containers (IBCs) for liquid dangerous goods require a ‘vibration test’ for type approval introduced in the United Nations Recommendations on the transport of dangerous goods. The test has to be performed as a repetitive shock test practically identical to the test procedure previously prescribed by the US Department of Transport. It is conceptually simple but has several drawbacks.

The kinetics and dynamics of a bouncing IBC have been investigated by means of simple computational models. With increasing complexity, partially plastic impact, elastodynamic response and the excitation of internal vibrations not directly affected by the bounces can be covered. The latter is a model for the sidewall vibrations. The numerical results show that the control over the specimens' response is only partially defined in the test procedure. Chaotic movements at resonance are possible and must be suppressed by changing the test parameters, which is mostly left to the test engineer. Accordingly, it is not possible to interpret the test results with a sound relation to real transport vibration environment.

Experimental results, however, suggest that vibration testing of IBCs improves safety because resonance effects in a frequency range excited by typical transportation loads exist. A more detailed numerical model is necessary for the assessment of the fatigue damage imposed on IBCs by the prescribed or alternative, more realistic test procedures. Copyright © 2011 John Wiley & Sons, Ltd.
Comparative Carbon Footprint of Packaging Systems for Tuna Products
Authors: Poovarodom Ngamtip , Ponnak Chularat , Manatphrom Natthaphon
Published: September 2011

The present study aimed to evaluate and compare the carbon footprint associated with canned tuna meat with a focus on packaging systems used to provide one single‐serve meal. The manufacturing process of retort pouches and cups produced 60% and 70% less greenhouse gas emissions, respectively, than that of metal cans. However, the overall carbon footprint of canned tuna in retort cups was 10% and 22% less than when packaged in metal cans and retort pouches, respectively. Packaging and its associated processing constituted significant fractions of the product's carbon footprint, ranging from 20% to 40%. Hotspots in the life cycle assessment of canned tuna are packaging production and disposal and product sterilization. The improvement of retort operation in terms of capacity and energy utilization and the efficiency of post‐consumption packaging material recovery are the key factors responsible for the reduction of a product's carbon footprint. These issues present a challenge to both the food industry and the local authorities. Copyright © 2011 John Wiley & Sons, Ltd.
Bayesian modelling and ensemble reconstruction of mid‐scale spatial variability in North Atlantic sea‐surface temperatures for 1850–2008
Authors: Karspeck Alicia R. , Kaplan Alexey , Sain Stephan R.
Published: September 2011

Existing historical records of sea‐surface temperature extending back to the mid‐1800s are a valuable source of information about climate variability on interannual and decadal time‐scales. However, the temporal and spatial irregularity of these data make them difficult to use in climate research, where gridded and complete data fields are expected for both statistical analysis and forcing numerical models.

Infilling methods based on constraining the solution to the linear space spanned by the leading eigenvectors of the global‐scale covariance, otherwise known as reduced‐space methods, have proven very successful in creating gridded estimates of sea‐surface temperature. These methods are especially useful for infilling the vast regions of unobserved ocean typical of the earliest segments of the data record. Regional variability, on the other hand, is not well represented by these methods, especially in data‐poor regions. Here we present a method for augmenting the established large‐scale reconstruction methods with a statistical model of the mid‐scale variability. Using high quality sea‐surface temperature data from the last 30 years including satellite‐derived records, we specify a spatially non‐stationary, anisotropic covariance model for the mid‐scale sea‐surface temperature variability. With the parameters of the covariance model estimated from the modern record, historical observations are used for conditioning the posterior distribution. Specifically, we form the expected value and correlated uncertainty of the mid‐scales as well as generating samples from the posterior.

While this work focuses on a limited domain in the midlatitude North Atlantic Ocean, the method employed here can be extended to global reconstructions. Copyright © 2011 Royal Meteorological Society
Coupled cluster and DFT calculations of 14N nuclear quadrupole coupling constants
Authors: Brzyska Agnieszka , Jaszuński Michał
Published: September 2011

The dependence of 14N quadrupole coupling constants calculated using coupled cluster theory on the level of approximation is examined for a series of small molecules. For HCN, HNC, CH3CN, and CH3NC, we use the coupled cluster singles‐and‐doubles with a noniterative perturbative triples correction—CCSD(T)—approach, and we analyze the basis set dependence of the results. For aziridine, diazirine, and cyclopropyl cyanide, we use the CCSD(T) approach, but smaller basis sets, and for the largest studied molecules—quinuclidine and hexamine—we present CCSD results. The differences between computed and experimental values for the best basis sets used are ≈ 5% at the CCSD level and decrease noticeably at the CCSD(T) level. The ‐ N≡C bonds are an exception—in this case the quadrupole coupling constants are very small, hence the differences between theory and experiment become larger (up to 9%). We also consider the performance of density functional theory, comparing the results for different density functionals with the coupled cluster values of the same constants. Most of the functionals provide results systematically improved with respect to the Hartree–Fock values, with 14N coupling constants in ‐ N≡C bonds being again an exception. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Theoretical study of disubstituted pyrrolopyrimidines as focal adhesion kinase inhibitors
Authors: de Oliveira Daniel Augusto Barra , de Oliveira Neto Marçal , Martins João B. L.
Published: September 2011

An in silico molecular modeling study of selected 7H‐pyrrolo[2,3‐d]pyrimidines with FAK inhibitory activities was performed. Rigid docking of each inhibitor at the FAK catalytic site was employed to obtain the most appropriate starting structures, followed by molecular mechanics‐based energy minimizations associated with molecular dynamics at the FAK binding site using the AMBER force field. Theoretical values of interaction energies obtained from the geometry optimization calculations for the protein‐inhibitor complexes were compared with published IC50 values for FAK and showed a reasonable correlation. Based on these results and in view of the geometry of the most potent inhibitors, two new molecular structures were designed as possible FAK inhibitors and submitted to the same theoretical procedures. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Codon usage roles in human papillomavirus
Authors: Zhao Kong‐Nan , Chen Jiezhong
Published: September 2011

Human papillomavirus (HPV) genomes, similar to other virus genomes, frequently have a G + C content significantly different from their host species. The HPV genomes show a strong codon usage bias to 18 codons, with 14 showing T at the third position amongst degenerately encoded amino acids. The codon usage pattern in HPV genome plays an important role, which regulates low or non‐translational expression of the viral capsid genes and results in very weak protein expression of oncogenes in a wide range of mammalian cells. Codon modification has been proved to be a powerful technology to overcome the translational blockage and weak expression of both HPV capsid genes and oncogenes in different expression systems. Furthermore, keratinocytes are the host cells of HPV infection; the codon usage in HPV capsid genes matches available aminoacyl‐tRNAs in differentiated keratinocytes to modulate their protein expression. HPV DNA vaccines with codon optimization have been shown to have higher immunogenicity and induce both strong cellular and humoral responses in animal models, which may be a promising form of therapeutic HPV vaccines. Copyright © 2011 John Wiley & Sons, Ltd.
Properly coloured copies and rainbow copies of large graphs with small maximum degree
Authors: Böttcher Julia , Kohayakawa Yoshiharu , Procacci Aldo
Published: September 2011

Let G be a graph on n vertices with maximum degree Δ. We use the Lovász local lemma to show the following two results about colourings χ of the edges of the complete graph Kn. If for each vertex v of Kn the colouring χ assigns each colour to at most (n ‐ 2)/(22.4Δ2) edges emanating from v, then there is a copy of G in Kn which is properly edge‐coloured by χ. This improves on a result of Alon, Jiang, Miller, and Pritikin [Random Struct. Algorithms 23(4), 409–433, 2003]. On the other hand, if χ assigns each colour to at most n/(51Δ2) edges of Kn, then there is a copy of G in Kn such that each edge of G receives a different colour from χ. This proves a conjecture of Frieze and Krivelevich [Electron. J. Comb. 15(1), R59, 2008].

Our proofs rely on a framework developed by Lu and Székely [Electron. J. Comb. 14(1), R63, 2007] for applying the local lemma to random injections. In order to improve the constants in our results we use a version of the local lemma due to Bissacot, Fernández, Procacci, and Scoppola [preprint, arXiv:0910.1824]. © 2011 Wiley Periodicals, Inc. Random Struct. Alg., 40, 425–436, 2012
Synthesis of Silver Nanoparticle–Hollow Titanium Phosphate Sphere Hybrid as a Label for Ultrasensitive Electrochemical Detection of Human Interleukin‐6
Authors: Peng Juan , Feng Li‐Na , Ren Zhong‐Jie , Jiang Li‐Ping , Zhu Jun‐Jie
Published: September 2011

A silver nanoparticle–hollow titanium phosphate sphere (AgNP–TiP) hybrid is successfully synthesized and used as a label for electrochemical detection of human interleukin‐6 (IL‐6). Hollow TiP spheres with a diameter of 430 nm and an average thickness of 40 nm are synthesized by a template approach. The AgNPs are incorporated in situ into the TiP shell via an exchange process. The as‐prepared AgNP–TiP hybrid shows outstanding biocompatibility, good dispersity and solubility in water, and high silver loading properties (289.2 mg of silver in 1.0 g of TiP). These advantages make the AgNP–TiP hybrid an effective candidate as an amplification label in immunoassay systems. Herein, the as‐prepared AgNP–TiP hybrid is attached to a signal antibody (Ab2) to produce Ab2–AgNP–TiP labels in the fabrication of an electrochemical immunosensor. The nanoparticle‐based amplification labels, upon coupling with a magnetic sensing array, give rise to an extremely sensitive response to IL‐6 in a linear range of 0.0005–10 ng mL−1 with a detection limit of 0.1 pg mL−1. The proposed sensor exhibits high specificity, good reproducibility, and long‐term stability, and may be a promising technique for protein and DNA detection.
Innovative Membran‐Stadiondächer in Kiew, Warschau und Vancouver
Authors: Cremers Jan , Grunwald Gregor
Published: September 2011

Während früher oft unter freiem Himmel gespielt wurde, haben die meisten Stadien heutzutage mindestens überdachte Ränge. Dies ist nicht nur Ausdruck eines gesteigerten Komfortbedürfnisses der Zuschauer, sondern eine zentrale Forderung der FIFA für Austragungsorte von internationalen Sportereignissen. Neben dem Witterungsschutz stehen hier vor allem die Lichtverhältnisse im Inneren im Mittelpunkt des Interesses – es geht um die Wachstumsbedingungen für den Rasen, um eine Reduktion des Aggressionspotenzials, aber vor allem um möglichst hochwertige Fernsehbilder: Stützenfreiheit und gleichmäßige Ausleuchtung mit begrenzten Kontrasten. Hier kommt ein zentraler Vorteil von biegeweichen Membranwerkstoffen zum Tragen: Transluzenz, zumeist mit hohem diffusen Anteil.

Innovative membrane stadia roofs in Kiev, Warsaw and Vancouver. Due to improved comfort levels and FIFA requirements, most new or rebuilt stadia in the world have their seats covered by a roof. This protection against weathering also significantly influences the indoor light situation. Adequate natural light levels are an important condition for the lawn to grow but also reduce visitor’s aggression potential and – of most importance – are the key to high quality television images in connection with a column‐free space. Here, membrane materials show their key advantages: very large column‐free span width and very even and low‐contrast light distribution through highly diffusing translucent textiles and foils.
Wandscheibentragfähigkeit von Sandwichelementen
Authors: Lange Jörg , Berner Klaus , Hörnel‐Metzger Beate
Published: September 2011

Für Gebäude aus tragenden Sandwichelementen ohne Unterkonstruktion ist zunächst zu klären, ob die Paneele geeignet sind, angreifende Horizontallasten als aussteifende Scheiben in den Baugrund abzuleiten. Dazu wurden Versuche zur Wandscheibentragfähigkeit von Sandwichelementen durchgeführt. Neben Einzelelementen wurden Scheiben aus zwei bzw. drei Sandwichpaneelen untersucht. Die Beanspruchbarkeiten sind insbesondere abhängig von Anzahl und Anordnung der Schrauben am Fußpunkt. Horizontallasten, in der Größenordnung wie sie in kleinen und mittleren Gebäuden auftreten [2], können problemlos aufgenommen werden.

Racking strength and stiffness of sandwich wall panels. For small buildings consisting of supporting sandwich panels without load‐bearing substructure it needs to be clarified first whether the panels are suitable to transfer horizontal loads in the plane of the wall to the foundation. For this purpose wall racking tests on sandwich elements were performed. Both single panels and two or three panel configurations were tested. Wall performance was mainly dependent on the number and the arrangement of screw fixings at the base rail of the panel. Horizontal loads, in a magnitude as they occur on small and medium‐sized buildings, can be borne easily.
Tragfähigkeit von Sandwichelementen mit profilierten Deckschichten und Öffnungen
Authors: Rädel Felicitas , Lange Jörg
Published: September 2011

Sandwichelemente mit profilierten Deckschichten werden üblicherweise als Dacheindeckung eingesetzt. Um gebäudetechnische und architektonische Anforderungen zu erfüllen, ist es notwendig Öffnungen in die Dachebene einzubringen. Im vorliegenden Aufsatz werden experimentelle und numerische Untersuchungen zur Tragfähigkeit von Sandwichelementen mit profilierten Deckschichten und Öffnungen vorgestellt. Aufbauend darauf werden Berechnungsansätze für die verbleibenden Traglasten des Restquerschnittes angegeben.

Load bearing capacity of sandwich panels with profiled faces and openings. Sandwich panels with profiled faces are usually used as roof covering. Due to different requirements it is necessary to cut openings into the roofing. In this paper experimental and numerical investigations of sandwich panels with profiled faces and openings are presented. As result, calculation models for the load bearing capacity of the effective cross section are given.
The impact of sourdough addition to frozen stored wheat‐flour rolls on glycemic response in human volunteers
Authors: Borczak Barbara , Sikora Elżbieta , Sikora Marek , Van Haesendonck Ingrid
Published: September 2011

The aim of this study was to examine the effect of sourdough addition to partially baked and frozen (PBF) wheat rolls on the glycemic index (GI). The study was performed on healthy humans (n = 15). The volunteers were asked to attend six times in the early morning, over 3 weeks. Each human tested four types of wheat rolls – two without sourdough addition: (i) fully baked, non‐frozen (FBNF); (ii) PBF; and two with the addition of 3% dehydrated sourdough: (iii) FBNF (FBNF + S), (iv) PBF (PBF + S). Glucose solution was used as a reference food and tested twice. Blood glucose concentrations were measured before consumption, as well as at 15, 30, 45, 60, 90, and 120 min after the start of the meal. In the study, the addition of 3% dehydrated sourdough to fresh and frozen wheat rolls resulted in a significant decrease in the glycemic response, by 24% – FBNF + S (GI = 63 ± 7) and PBF + S (GI = 43 ± 4) – compared to the samples without sourdough: FBNF (GI = 87 ± 11), PBF (GI = 67 ± 3) (p ≤ 0.05). Both factors (freezing and sourdough), applied to the wheat rolls at the same time, statistically significantly reduced the GI, by 44% (p ≤ 0.05). The results of the study show that sourdough supplementation separately and sourdough supplementation combined with frozen storage of white wheat rolls have a significant impact on the glycemic response.
Control of a wind farm with an internal direct current collection grid
Authors: Max Lena , Thiringer Torbjörn , Carlson Ola
Published: September 2011

For a high‐voltage, direct current connected wind farm, an internal direct current (DC) collection grid is a possible further development that can reduce the weight of the transformers significantly, with average losses for the DC system of 3%. For the internal DC grid, the DC/DC converters control the power flow and thereby also the voltages. In this paper, the control of the DC/DC converters in the wind farm is investigated in detail. The control strategy is presented, and suitable time constants are chosen depending on the switching frequency of the converters. Also, the required capacitor size to keep the voltage variations within 5% of the rated value in the case without communication within the wind farm is derived. It is shown that the control is stable and can handle faults on the external grid without any communication within the wind farm. Copyright © 2011 John Wiley & Sons, Ltd.
Assessment of lightning current parameters suitable for wind turbine overvoltage protection analysis
Authors: Sarajcev Petar , Goic Ranko
Published: September 2011

A selection procedure for determining the lightning current parameters, suitable for wind turbine overvoltage protection analysis, will be presented in this paper. It will be based on the mathematical model that accounts for the wind turbine geometry, keraunic level, statistical distribution of lightning current parameters and correlation between statistical variables defining lightning current waveshape. Theoretical analysis will be backed up by the most recent propositions of parameters that define statistical distributions and thereafter applied on the concrete wind turbine example. Subsequently, obtained results would provide insight into the selection procedure for the lightning current parameters (i.e., amplitude, front duration, wave duration and polarity), associated with lightning stroke incidence to wind turbines. Emphases will be given to the modern new‐generation wind turbines. This selection procedure could be subsequently applied in the analysis (and design) of the wind turbine and wind farm overvoltage protection, with emphasis on the so‐called back‐surge phenomenon. Copyright © 2011 John Wiley & Sons, Ltd.
Genetic algorithms for clustering and fuzzy clustering
Authors: Bandyopadhyay Sanghamitra
Published: September 2011

Clustering has been an area of intensive research for several decades because of its multifaceted applications in innumerable domains. Clustering can be either Boolean, where a single data point belongs to exactly one cluster, or fuzzy, where a single data point can have nonzero belongingness to more than one cluster. Traditionally, optimization of some well‐defined objective function has been the standard approach in both clustering and fuzzy clustering. Hence, researchers have investigated the utility of evolutionary computing and related techniques in this regard. The different approaches differ in their choice of the objective function and/or the optimization strategy used. In particular, clustering using genetic algorithms (GAs) has attracted attention of researchers, and has been studied extensively. This paper presents a short review of some of different approaches of GA‐based clustering methods. Two techniques, one with fixed number of clusters and another with a variable number of fuzzy clusters, are described along with some experimental results on numerical as well as image data sets. © 2011 John Wiley & Sons, Inc. WIREs Data Mining Knowl Discov 2011 1 524–531 DOI: 10.1002/widm.47

This article is categorized under:

Algorithmic Development > Structure Discovery

Technologies > Structure Discovery and Clustering
Why mentoring in the workplace works
Authors: Hamilton Mary Agnes , Hamilton Stephen F.
Published: September 2011

Workplaces are ideal contexts for mentoring relationships between adults and older youth. To teach the competencies required in contemporary workplaces (many of which are equally useful in other settings), mentors need to use sophisticated teaching behaviors, which the authors characterize as reflective questioning and problem solving.
Tetraethylene Glycol Adducts of Alkaline Earth Halides
Authors: Gschwind Fabienne , Fromm Katharina M.
Published: September 2011

Abstract. Reaction of commercially available tetraethylene glycol with different alkaline earth metal halides affords tetraethylene glycol complexes with different coordination numbers at the metal ion and structural features; depending on the ionic radius of the metal ion, one or two ligand molecules will be coordinated to the metal ion. In this article we will first present complexes with Mg2+([Mg(C8H18O5)(H2O)2]Cl·I) (1), Ca2+([Ca(C8H18O5)·3H2O]Cl2 (2), [Ca(C8H18O5)(H2O)2]I2 (3), [Ca(C8H18O5)(H2O)3]I2·H2O (4), ([Ca(C8H18O5)(H2O)3]Cl·I) (5),Sr2+ ([Sr(C8H18O5)(H2O)4]Cl2 (6), [Sr(C8H18O5)2]I2·CHCl3) (7) and Ba2+ ([Ba(C8H18O5)2]I2) (8). Secondly we will show preliminary tests for the combustion of some selected compounds and their thermal decomposition behavior. Furthermore, selected compounds were evaporated by MOCVD (metal organic chemical vapor deposition) to evaluate their capacity as future single source precursors for oxide materials.
Synthesis, Structure, and Surface Photoelectric Properties of Two Novel Cobalt(II) Complexes
Authors: Shi Zhong‐Feng , Li Jia‐Ming , Li Lei , Niu Shu‐Yun
Published: September 2011

Abstract. Two novel cobalt(II) complexes {[Co2(Hdcbp)4(H2O)2]n·7n(H2O)(1) and [Co(Q)2(CH3OH)2] (2) (H2dcbp = 2,2′‐bipyridyl‐4,4′‐dicarboxylic acid, HQ = quinoline‐2‐carboxylic acid) were synthesized by hydrothermal methods and characterized by single‐crystal X‐ray diffraction, IR, UV/Vis, and surface photovoltage spectroscopy (SPS). Structural analysis indicated that complex 1 has a 1D chain structure which is further extended to a 3D supramolecular architecture by hydrogen bonds. Complex 2 is a mononuclear complex, which is further extended to a 2D supramolecular architecture by hydrogen bonds. The SPS of complexes 1 and 2 indicate that there are positive response bands in the range of 300–600 nm, which show different levels of photoelectric conversion properties. The intensity, position in SPS are obviously different since the structure, coordinated environment of the centered metals are different. There are good relationships between SPS and UV/Vis spectra.
Between Sin and Salvation: The Seventeenth-Century Dutch Artisan Pieter Plockhoy and His Ethics of Work
Authors: Looijesteijn Henk
Published: September 2011

There have been few attempts systematically to study the ethics of work in the early modern age on the basis of contemporary sources. Such a study should start with case studies of individual thinkers, as stepping stones to a more comprehensive study of the ethics of work. This article provides such a case study, of the seventeenth-century Dutch artisan Pieter Plockhoy (c.1620–1664). As will be shown, work was a central component of Plockhoy's philosophy of true, practical Christianity, and on the basis of his tracts a more or less coherent ethics of work can be reconstructed. Although this article concentrates on Plockhoy's philosophy of labour, his thought fits into a broader context of related contemporary thinkers, many of whom shared his concerns. Thus the article shows that for scholars wishing to study the ethics of work there is still a whole field which, though yielding a potentially rich harvest, lies fallow.
‘I wasn't angry, because I couldn't believe it was happening’: Affect and discourse in responses to 9/11
Authors: SOLOMON TY
Published: September 2011

While the recent interest in affects and emotions in world politics is encouraging, the crucial relationships between affect, emotion, and discourse have remained largely under-examined. This article offers a framework for understanding the relations between affect and discourse by drawing upon the theories of Jacques Lacan. Lacan conceptualises affect as an experience which lies beyond the realm of discourse, yet nevertheless has an effect upon discourse. Emotion results when affects are articulated within discourse as recognisable signifiers. In addition, Lacanian theory conceptualises affect and discourse as overlapping yet not as coextensive, allowing analyses to theoretically distinguish between discourses which become sites of affective investment for audiences and those that do not. Thus, analysing the mutual infusion of affect and discourse can shed light on why some discourses are more politically efficacious than others. The empirical import of these ideas is offered in an analysis of American affective reactions to 11 September 2001.
Design and analysis of a 3-DOF spherical parallel manipulator – CORRECTED VERSION
Authors: Zhang Dan , Zhang Fan
Published: September 2011

In this paper, we propose a unique, 3 degree-of-freedom (DOF) parallel wrist. Specifically, an over-constrained spherical 3-DOF parallel mechanism is presented and the modified structure, which avoids the redundant constraints, is also introduced.
Video-stimulated reflection as a professional development tool in interactive whiteboard research
Authors: Cutrim Schmid Euline
Published: September 2011

Several authors (e.g., Mcniff & Whitehead, 2006; Wallace, 1998) defend the idea that teachers’ own involvement in research has the potential to encourage professional growth. Journal writing, teacher logs, written narratives and stimulated recall are some examples of methods that have been used by researchers to encourage and support teachers’ reflective practice in teacher-researcher collaborative research. This paper discusses the use of video-stimulated reflection as both a research method and as a means for teacher professional growth. The research findings are drawn from a longitudinal study that investigates a model of Interactive Whiteboard (IWB) technology professional development programme. The research was carried out in the form of seven in-depth case studies with English as a Foreign Language (EFL) teachers in German secondary/vocational schools, as they learn how to integrate the IWB into their teaching. Research data were collected via a variety of research instruments, namely classroom observations and field notes, video recordings of school lessons and teacher training workshops, interviews and video-stimulated reflection. Findings based on the analysis of the copious amount of data gathered indicate that the video-stimulated dialogues were used by the teachers as effective opportunities for reflection, self-evaluation and pedagogical development.
Learning to teach with videoconferencing in primary foreign language classrooms
Authors: Whyte Shona
Published: September 2011

This qualitative study investigates the relationship between learning opportunities and teacher cognition in the context of a videoconferencing (VC) project for foreign languages (FL) in French primary schools. Six generalist primary teachers were followed throughout the initial six-month stage of the initiative, and data were collected from learners, teachers, and trainers via questionnaire, video and audio recordings of class and feedback sessions, online teacher and trainer discussion, and video-stimulated recall interviews. Interview data revealed distinct teacher profiles involving differences in orientation to teaching and the teacher, learning and learners, and technology. These profiles corresponded to different teaching strategies and resulted in varying patterns of learner interaction in VC sessions. Teachers’ comments showed them to be guided by general rather than FL-specific pedagogical principles, and pedagogical concerns frequently intersected with technical issues as teachers learned to exploit the new VC technology. While most teachers valued spontaneous FL interaction as a key VC affordance, the filmed sessions revealed little unplanned learner-learner communication. This finding is related to teachers’ views of second language acquisition as product rather than a process; for more learner-centred teachers, spontaneity was affected by rehearsal, and for more teacher-oriented practitioners, sustained teacher intervention influenced patterns of learner participation. In addition to these classroom findings, the study highlights the value of this type of participant research in facilitating the exchange of resources and expertise, classroom video footage, and participants’ comments and queries, and thus contributing to professional development in CALL and CMC-based teacher education.
Identifying target groups for the prevention of depression among caregivers of dementia patients
Authors: Joling Karlijn J. , Smit Filip , van Marwijk Harm W. J. , van der Horst Henriëtte E. , Scheltens Philip , Schulz Richard , van Hout Hein P. J.
Published: September 2011

Background:Depression in informal caregivers of persons with dementia is a major, costly and growing problem. However, it is not yet clear which caregivers are at increased risk of developing depression. With this knowledge preventive strategies could focus on these groups to maximize health gain and minimize effort.

Methods:The onset of clinically relevant depression was measured with the Center for Epidemiologic Studies - Depression Scale in 725 caregivers who were not depressed at baseline and who were providing care for a relative with dementia. Caregivers were followed over 18 months. The indices calculated to identify the most important risk indicators were: odds ratio, attributable fraction, exposure rate and number needing to be treated.

Results:The following significant indicators of depression onset were identified: increased initial depressive symptoms, poor self-rated health status and white or Hispanic race/ethnicity. The incidence of depression would decrease by 72.3% (attributive fraction) if these risk indicators together are targeted by a completely effective intervention. Race/ethnicity was not a significant predictor if caregivers of patients who died or were institutionalized were left out of the analyses.

Conclusion:Detection of only a few characteristics makes it possible to identify high-risk groups in an efficient way. Focusing on these easy-to-assess characteristics might contribute to a cost-effective prevention of depression in caregivers.
Nocturnal emissions
Authors: Jacobs Howy
Published: September 2011

Howy argues that sophisticated communication technology is no substitute for the face‐to‐face contacts that are vital to scientific work. Instead of ever‐fancier electronic devices, we should be focusing on making travel more efficient and humane.
Coherent dynamics and association networks among lake bacterioplankton taxa
Authors: Eiler Alexander , Heinrich Friederike , Bertilsson Stefan
Published: September 2011

Bacteria have important roles in freshwater food webs and in the cycling of elements in the ecosystem. Yet specific ecological features of individual phylogenetic groups and interactions among these are largely unknown. We used 454 pyrosequencing of 16S rRNA genes to study associations of different bacterioplankton groups to environmental characteristics and their co-occurrence patterns over an annual cycle in a dimictic lake. Clear seasonal succession of the bacterioplankton community was observed. After binning of sequences into previously described and highly resolved phylogenetic groups (tribes), their temporal dynamics revealed extensive synchrony and associations with seasonal events such as ice coverage, ice-off, mixing and phytoplankton blooms. Coupling between closely and distantly related tribes was resolved by time-dependent rank correlations, suggesting ecological coherence that was often dependent on taxonomic relatedness. Association networks with the abundant freshwater Actinobacteria and Proteobacteria in focus revealed complex interdependencies within bacterioplankton communities and contrasting linkages to environmental conditions. Accordingly, unique ecological features can be inferred for each tribe and reveal the natural history of abundant cultured and uncultured freshwater bacteria.
Characterization of a novel peripheral pro-lipolytic mechanism in mice: role of VGF-derived peptide TLQP-21
Authors: Possenti Roberta , Muccioli Giampiero , Petrocchi Pamela , Cero Cheryl , Cabassi Aderville , Vulchanova Lucy , Riedl Maureen S. , Manieri Monia , Frontini Andrea , Giordano Antonio , Cinti Saverio , Govoni Paolo , Graiani Gallia , Quaini Federico , Ghè Corrado , Bresciani Elena , Bulgarelli Ilaria , Torsello Antonio , Locatelli Vittorio , Sanghez Valentina , Larsen Bjarne D. , Petersen Jorgen S. , Palanza Paola , Parmigiani Stefano , Moles Anna , Levi Andrea , Bartolomucci Alessandro
Published: September 2011

The peptides encoded by the VGF gene are gaining biomedical interest and are increasingly being scrutinized as biomarkers for human disease. An endocrine/neuromodulatory role for VGF peptides has been suggested but never demonstrated. Furthermore, no study has demonstrated so far the existence of a receptor-mediated mechanism for any VGF peptide. In the present study, we provide a comprehensive in vitro, ex vivo and in vivo identification of a novel pro-lipolytic pathway mediated by the TLQP-21 peptide. We show for the first time that VGF-immunoreactivity is present within sympathetic fibres in the WAT (white adipose tissue) but not in the adipocytes. Furthermore, we identified a saturable receptor-binding activity for the TLQP-21 peptide. The maximum binding capacity for TLQP-21 was higher in the WAT as compared with other tissues, and selectively up-regulated in the adipose tissue of obese mice. TLQP-21 increases lipolysis in murine adipocytes via a mechanism encompassing the activation of noradrenaline/β-adrenergic receptors pathways and dose-dependently decreases adipocytes diameters in two models of obesity. In conclusion, we demonstrated a novel and previously uncharacterized peripheral lipolytic pathway encompassing the VGF peptide TLQP-21. Targeting the sympathetic nerve–adipocytes interaction might prove to be a novel approach for the treatment of obesity-associated metabolic complications.
Enhancement of microwave oscillation under angled in-plane magnetic field in ferromagnetic nano-contact spin-valves
Authors: Suzuki Hiroaki , Nakamura Tetsuya , Endo Hiroaki , Doi Masaaki , Tsukahara Hiroshi , Imamura Hiroshi , Fuke Hiromi N. , Hashimoto Susumu , Iwasaki Hitoshi , Sahashi Masashi
Published: September 2011

We investigated the microwave oscillation of resistance due to spin-transfer torque in ferromagnetic nano-contact spin-valves under an external in-plane magnetic field. We varied the direction of the external magnetic field and therefore the relative angle, θ, between magnetizations of the free and reference layers. We showed that the level of microwave oscillation takes a maximum value at around θ = 140°. We also showed that the microwave oscillation frequency increases with increases in the applied direct current.
Texture and microstructure evolution in single-phase TixTa1−xN alloys of rocksalt structure
Authors: Koutsokeras L. E. , Abadias G. , Patsalas P.
Published: September 2011

The mechanisms controlling the structural and morphological features (texture and microstructure) of ternary transition metal nitride thin films of the TixTa1−xN system, grown by various physical vapor deposition techniques, are reported. Films deposited by pulsed laser deposition, dual cathode magnetron sputtering, and dual ion beam sputtering have been investigated by means of x-ray diffraction in various geometries and scanning electron microscopy. We studied the effects of composition, energetic, and kinetics in the evolution of the microstructure and texture of the films. We obtain films with single and mixed texture as well as films with columnar “zone-T” and globular type morphology. The results have shown that the texture evolution of ternary transition metal nitrides as well as the microstructural features of such films can be well understood in the framework of the kinetic mechanisms proposed for their binary counterparts, thus giving these mechanisms a global application.
Electron-beam activated thermal sputtering of thermoelectric materials
Authors: Wu Jinsong , He Jiaqing , Han Mi-Kyung , Sootsman Joseph R. , Girard Steven , Arachchige Indika U. , Kanatzidis Mercouri G. , Dravid Vinayak P.
Published: September 2011

Thermoelectricity and Seebeck effect have long been observed and validated in bulk materials. With the development of advanced tools of materials characterization, here we report the first observation of such an effect in the nanometer scale: in situ directional sputtering of several thermoelectric materials inside electron microscopes. The temperature gradient introduced by the electron beam creates a voltage-drop across the samples, which enhances spontaneous sputtering of specimen ions. The sputtering occurs along a preferential direction determined by the direction of the temperature gradient. A large number of nanoparticles form and accumulate away from the beam location as a result. The sputtering and re-crystallization are found to occur at temperatures far below the melting points of bulk materials. The sputtering occurs even when a liquid nitrogen cooling holder is used to keep the overall temperature at −170 °C. This unique phenomenon that occurred in the nanometer scale may provide useful clues to understanding the mechanism of thermoelectric effect.
Depth distribution of silver particulate films deposited in softened polystyrene substrates studied through Rutherford backscattering spectrometry
Authors: Thompson Richard L. , Gurumurthy S. C. , Pattabi Manjunatha
Published: September 2011

The depth distribution of silver particulate films deposited on softened polystyrene substrates has been studied through Rutherford backscattering spectrometry (RBS). 150 nm thick silver films were deposited on polystyrene (PS) coated glass substrates held at 455 K and 490 K in a vacuum of 8 × 10−6 Torr. The substrates were irradiated with 8 MeV electrons to a dose of 25 kGy prior to deposition. Ion scattering measurements indicated that the silver particulates are formed at a few tens of nanometers beneath the PS surface for both unirradiated and irradiated substrates. The particulate structure seems to be a two-dimensional array rather than a three-dimensional distribution. The morphology of the particulate structure, the depth of maximum concentration of the particles as well as the width of the distribution seems to depend on the deposition rate and substrate temperature. The electron irradiation of the PS substrate gives rise to the modification of the morphology of the particulate structure due to the induced polymer-metal interaction arising from the free radicals created by the irradiation.