bluuebunny/crossref_metadata_2025 huggingface dataset:
Geographic Information Systems
Authors: Ramirez J. Raul
Published: December 2007

A geographic imformation system (GIS) is a set of computer‐based tools to collect, store, retrieve, manipulate, visualize, and analyze geo‐spatial information (information identified by its location on the surface of reference, for example, the Earth). This article describes the major components of a GIS (hardware and software) with emphasis in the central processing units and peripheral device and major software components: collection, storage, retrieval, manipulation, query and analyze, and visualization. This discussion is followed by a discussion of applications in several fields using a set of examples to illustrate these topics. Then, the concept and implications of quality in GIS (spatial data quality, quality on embedded and external models) is discussed. Finally, some comments are presented over the future of GIS.
Programming Models: Client–Server, Process Groups, and Peer‐to‐Peer
Authors: van Renesse Robbert
Published: December 2007

This article discusses various programming models for implementing distributed applications. We focus mostly on data‐sharing rather than CPU‐sharing applications. First we describe the client‐server model, and how basic distributed applications can be built using Remote Procedure Calls. We then move on to discuss how more sophisticated distributed applications can be developed with process groups and look in more detail at the virtual synchrony and publish/subscribe paradigms. Finally, we consider highly scalable peer‐to‐peer approaches to resource sharing and location, application level routing, and monitoring and aggregation.
A multicenter retrospective study defining the clinical and hematological manifestations of brucellosis and pancytopenia in a large series: Hematological malignancies, the unusual cause of pancytopenia in patients with brucellosis
Authors: Sari Ismail , Altuntas Fevzi , Hacioglu Sibel , Kocyigit Ismail , Sevinc Alper , Sacar Suzan , Deniz Kemal , Alp Emine , Eser Bulent , Yildiz Orhan , Kaynar Leylagul , Unal Ali , Cetin Mustafa
Published: December 2007

The aim of the study is to review the clinical manifestations and the hematological findings of brucellosis and pancytopenia, with or without hematological malignancies. The records of 202 patients with brucellosis were evaluated retrospectively. Among these cases of brucellosis seen in a 6 year period between April 1999 and June 2005, 30 patients with pancytopenia were identified. The most common manifestation was fever, followed by weight loss, anorexia, malaise, arthralgia, and hepatosplenomegaly. Bone marrow biopsies revealed hypercellularity or normocellularity. The most common findings in the bone marrow evaluation were histiocytic hemophagocytosis and granulomas. Among all cases, we diagnosed 5 hematological malignancies (1 acute myelogenous leukemia, 2 acute lymphoblastic leukemia, and 2 multiple myeloma) concurrently with brucellosis. The clinical symptoms and findings were similar in patients with and without malignancies. In cases with malignancies, the bone marrow biopsy revealed predominant primary disease involvement. Significant increases in ESR and CRP, severe anemia and thrombocytopenia were observed in patients with malignancies. Peripheral blood counts in patients without malignancies returned to normal after antibiotic treatment for brucellosis. However, pancytopenia in two patients with malignancies did not recover because of primary resistant disease. We conclude that while histiocytic hemophagocytosis may be considered as a major cause of pancytopenia, leukemic infiltration can also be an extreme and unusual cause of pancytopenia in patients in whom brucellosis was concurrently diagnosed with hematological malignancies. Am. J. Hematol., 2008. © 2007 Wiley‐Liss, Inc.
First Homo erectus from Turkey and implications for migrations into temperate Eurasia
Authors: Kappelman John , Alçiçek Mehmet Cihat , Kazancı Nizamettin , Schultz Michael , Özkul Mehmet , Şen Şevket
Published: December 2007

Remains of fossil hominins from temperate regions of the Old World are rare across both time and space, but such specimens are necessary for understanding basic issues in human evolution including linkages between their adaptations and early migration patterns. We report here the remarkable circumstances surrounding the discovery of the first fossil hominin calvaria from Turkey. The specimen was found in the Denizli province of western Turkey and recovered from within a solid block of travertine stone as it was being sawed into tile‐sized slabs for the commercial natural stone building market. The new specimen fills an important geographical and temporal gap and displays several anatomical features that are shared with other Middle Pleistocene hominins from both Africa and Asia attributed to Homo erectus. It also preserves an unusual pathology on the endocranial surface of the frontal bone that is consistent with a diagnosis of Leptomeningitis tuberculosa (TB), and this evidence represents the most ancient example of this disease known for a fossil human. TB is exacerbated in dark‐skinned peoples living in northern latitudes by a vitamin D deficiency because of reduced levels of ultraviolet radiation (UVR). Evidence for TB in the new specimen supports the thesis that reduced UVR was one of the many climatic variables presenting an adaptive challenge to ancient hominins during their migration into the temperate regions of Europe and Asia. Am J Phys Anthropol, 2008. © 2007 Wiley‐Liss, Inc.
Functional neuroimaging of belief, disbelief, and uncertainty
Authors: Harris Sam , Sheth Sameer A. , Cohen Mark S.
Published: December 2007

Objective

The difference between believing and disbelieving a proposition is one of the most potent regulators of human behavior and emotion. When one accepts a statement as true, it becomes the basis for further thought and action; rejected as false, it remains a string of words. The purpose of this study was to differentiate belief, disbelief, and uncertainty at the level of the brain.

Methods

We used functional magnetic resonance imaging (fMRI) to study the brains of 14 adults while they judged written statements to be “true” (belief), “false” (disbelief), or “undecidable” (uncertainty). To characterize belief, disbelief, and uncertainty in a content‐independent manner, we included statements from a wide range of categories: autobiographical, mathematical, geographical, religious, ethical, semantic, and factual.

Results

The states of belief, disbelief, and uncertainty differentially activated distinct regions of the prefrontal and parietal cortices, as well as the basal ganglia.

Interpretation

Belief and disbelief differ from uncertainty in that both provide information that can subsequently inform behavior and emotion. The mechanism underlying this difference appears to involve the anterior cingulate cortex and the caudate. Although many areas of higher cognition are likely involved in assessing the truth‐value of linguistic propositions, the final acceptance of a statement as “true” or its rejection as “false” appears to rely on more primitive, hedonic processing in the medial prefrontal cortex and the anterior insula. Truth may be beauty, and beauty truth, in more than a metaphorical sense, and false propositions may actually disgust us. Ann Neurol 2007
Alkaline hydrolysis of methyl acrylate grafted cellulose fibers
Authors: Jain Vaibhav , Ni Yonghao
Published: December 2007

In this work, methyl acrylate grafted cellulose fibers were hydrolyzed in an aqueous NaOH solution to obtain a superabsorbent hydrogel. The effect of process variables, such as the hydrolysis reaction time, temperature, and NaOH concentration, during alkaline hydrolysis were carefully determined and optimized. The degree of hydrolysis was estimated on the basis of the determination of the carboxylate group contents. The material loss during hydrolysis followed a first‐order reaction mechanism. The differences in the behavior of the grafted fibers during hydrolysis could be explained by their structural differences. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis and characterization of polypyrrole rod doped with p‐toluenesulfonic acid via micelle formation
Authors: Kim Duk Ki , Oh Kyung Wha , Ahn Hee Jun , Kim Seong Hun
Published: December 2007

Rod‐type polypyrrole (PPY) doped with p‐toluenesulfonic acid (TSA) was synthesized by chemical oxidative polymerization via a self‐assembly process. The shape of the PPY particles is mainly determined by the ratio of TSA/pyrrole (PY) and feed rate of the oxidant. Particle of different shapes (rod, grain, and partially rod) exhibit differences in morphology, electrical properties, dispersity, and thermal properties. Wide‐angle X‐ray diffraction patterning analysis was used to investigate the mechanism of rod formation. The effect of the TSA concentration on the PPY structure was investigated using Fourier transform infrared spectroscopy. The PPY rods doped with TSA exhibited better electrical conductivity than granular PPY doped with TSA, and their dispersity and thermal stability were also higher. Self‐orientation of PPY in the micelles of TSA and high crystallinity of the rod particles led to improved thermal stability. Hence, the decomposition temperature of the polymer chain was considerably increased. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008
Effects of the cosurfactant 1‐butanol and feed composition on nanoparticle properties produced by microemulsion copolymerization of styrene and methyl methacrylate
Authors: Otto Daniel P. , Vosloo Hermanus C. M. , Liebenberg Wilna , de Villiers Melgardt M.
Published: December 2007

The concentration of the cosurfactant 1‐butanol (BuOH) determined the polymer weight and size for a series of poly(styrene‐co‐methyl methacrylate)s (P(St‐co‐MMA)) synthesized by the free‐radical (o/w) microemulsion technique. A factorial design established the levels of the experimental conditions for the polymerization i.e., concentration of the surfactant, sodium dodecyl sulfate (SDS); concentration of the cosurfactant, BuOH; temperature and ratio of the styrene (St) to methyl methacrylate (MMA). An increase in the weight‐average molecular weight (Mw) and number‐average molecular weight (Mn) was observed in the P(St‐co‐MMA) series with an increase in BuOH concentration from 1 to 5 wt %. These effects could arise from the micellar aggregation induced by interfacial BuOH. The unique micellar conditions could be exploited to synthesize copolymers of varying molecular weight and size. Additionally, the composition of the copolymers was virtually templates of the feed composition. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008
Syntheses and Biological Activities of Benzimidazolo[2,1‐b] benzo[e]thiazepin‐5(10H)‐ones
Authors: Rastkari Noushin , Abdollahi Mohammad , Ahmadkhaniha Reza , Shafiee Abbas
Published: December 2007

Substituted benzimidazolo[2,1‐b]benzo[e]thiazepin‐5(10H)‐one derivatives were prepared in moderate to good yield by reaction of mercapto benzimidazole derivatives with 2‐chloromethylbenzoyl chloride as a coupling component. Their structures were confirmed by elemental analysis, IR, NMR, and MS. Their antioxidant properties were evaluated by several methods: scavenging effect on 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radicals, reducing power assay, and inhibition of lipid peroxidation. In DPPH assay, 3h exhibited an activity stronger than trolox. In the reducing power assay and inhibition of lipid peroxidation, compound 3a was more active than 3h and similar to trolox. The antidiabetic effect was also determined, and the antidiabetic activities were correlated with their antioxidant properties, compound 3a was the most active compound in the in‐vivo experiments.
Usage impact factor: The effects of sample characteristics on usage‐based impact metrics
Authors: Bollen Johan , Sompel Herbert Van de
Published: December 2007

There exist ample demonstrations that indicators of scholarly impact analogous to the citation‐based ISI Impact Factor can be derived from usage data; however, so far, usage can practically be recorded only at the level of distinct information services. This leads to community‐specific assessments of scholarly impact that are difficult to generalize to the global scholarly community. In contrast, the ISI Impact Factor is based on citation data and thereby represents the global community of scholarly authors. The objective of this study is to examine the effects of community characteristics on assessments of scholarly impact from usage. We define a journal Usage Impact Factor that mimics the definition of the Thomson Scientific ISI Impact Factor. Usage Impact Factor rankings are calculated on the basis of a large‐scale usage dataset recorded by the linking servers of the California State University system from 2003 to 2005. The resulting journal rankings are then compared to the Thomson Scientific ISI Impact Factor that is used as a reference indicator of general impact. Our results indicate that the particular scientific and demographic characteristics of a discipline have a strong effect on resulting usage‐based assessments of scholarly impact. In particular, we observed that as the number of graduate students and faculty increases in a particular discipline, Usage Impact Factor rankings will converge more strongly with the ISI Impact Factor.
An HPSG approach to Arabic nominal sentences
Authors: Mutawa A.M. , Alnajem Salah , Alzhouri Fadi
Published: December 2007

This paper introduces a grammar for Arabic nominal sentences written in the formalism of Head‐Driven Phrase Structure Grammar (HPSG). This grammar covers simple Arabic nominal sentences, though the same approach can be extended to cover other types of Arabic nominal sentences. The formalization has been implemented using the Linguistic Knowledge Building (LKB) system.
Writing consumer research: the world according to Belk
Authors: Brown Stephen , Schau Hope Jensen
Published: December 2007

Writing is a core scholarly competence. Not only is it a skill that every academic must acquire, regardless of their methodological, philosophical or empirical affiliations, but also it is ‘a substantial differentiating characteristic of eminent researchers’. This article offers an analysis of the writing style of one of the field's most eminent researchers, Russell W. Belk. It identifies five literary devices that help Belk's writing stand out from the crowd and, while the article does not claim to contain the secret of writing success, it considers the crucial part writing plays in the consumer research process.

Copyright © 2007 John Wiley & Sons, Ltd.
Conformational Analysis of a Dermatan Sulfate‐Derived Tetrasaccharide by NMR, Molecular Modeling, and Residual Dipolar Couplings
Authors: Silipo Alba , Zhang Zhenqing , Cañada F. Javier , Molinaro Antonio , Linhardt Robert J. , Jiménez‐Barbero Jesús
Published: December 2007

The solution conformation behavior of a dermatan‐derived tetrasaccharide—ΔHexA‐(1→3)‐GalNAc4S‐β‐(1→4)‐IdoA‐α‐(1→3)‐red‐GalNAc4S (S is a sulfate group)—has been explored by means of NMR spectroscopy, especially by NOE‐based conformational analysis. The tetrasaccharide was present as four species, two of which are chemically different in the anomeric orientation of the reducing 2‐deoxy‐2‐acetamido‐galactose (red‐GalNAc) residue, while the other two are the result of different conformations of the iduronic acid (IdoA) unit. The two α–β‐interconverting anomers were present in a 0.6:1 ratio. Ring conformations have been defined by analysis of 3JH,H coupling constants and interresidual NOE contacts. Both 2‐deoxy‐2‐acetamido‐galactose (GalNAc) residues were found in the 4C1 chair conformation, the unsaturated uronic acid (Δ‐Hex A) adopts a strongly predominant half‐chair 1H2 conformation, while the IdoA residue exists either in the 1C4 chair or in the 2S0 skewed boat geometries, in a 4:1 ratio. There is a moderate flexibility of Φ and Ψ torsions as suggested by nuclear Overhauser effects (NOEs), molecular modeling (MM), and molecular dynamics (MD) studies. This was further investigated by residual dipolar couplings (RDCs). One‐bond CH RDCs (1DC,H) and long‐range H–H (3DH,H) RDCs were measured for the tetrasaccharide in a phage solution and interpreted in combination with restrained MD simulation. The RDC‐derived data substantially confirmed the validity of the conformer distribution resulting from the NOE‐derived simulations, but allowed an improved definition of the conformational behavior of the oligosaccharides in solution. In summary, the data show a moderate flexibility of the four tetrasaccharide species at the central glycosidic linkage. Differences in the shapes of species with the IdoA in skew and in chair conformations and in the distribution of the sulfate groups have also been highlighted.
Editorial for “Mammography Screening of Women in Their Forties
Authors: Brem Rachel F.
Published: December 2007

Mammographic screening has resulted in ≤44% reduction in breast cancer mortality. Understanding what influences and motivates women to obtain mammograms is critical to achieving the highest compliance rate
Transient expression of LIM‐domain transcription factors is coincident with delayed maturation of photoreceptors in the chicken retina
Authors: Fischer Andy J. , Foster Shane , Scott Melissa A. , Sherwood Patrick
Published: December 2007

In the retina of warm‐blooded vertebrates, photoreceptors are specified many days before the onset of synaptogenesis and the expression of photopigments. The factors that regulate the maturation of photoreceptors in the developing retina remain unknown. We report here that photoreceptors transiently express LIM‐domain transcription factors during the development of the chicken retina. We examined the differentiation of photoreceptors through the normal course of embryonic development and at the far periphery of the postnatal retina, where the differentiation of photoreceptors is slowed and persists across a spatial gradient. In the embryonic retina, we find visinin‐positive photoreceptors that transiently express Islet2 and Lim3 starting at E8 and ending around E15, but persisting in far peripheral regions of the retina through the first 2 weeks of postnatal development. During early stages of photoreceptor maturation, there is coincident and transient expression of the LIM‐domain factors with axonin1, a cell surface glycoprotein that is a member of the immunoglobulin superfamily. Coincident with the downregulation of Islet2 and Lim3, we find the upregulation of calbindin, red/green opsin, rhodopsin, and a synaptic marker in the outer plexiform layer (OPL; dystrophin). In the periphery of the postnatal retina, photoreceptors that express Islet2, Lim3, and axonin1 do not overlap with photoreceptors that express calbindin, red/green opsin, rhodopsin, and dystrophin. We propose that Islet2 and Lim3 may promote the expression of genes that are involved in the early stages of differentiation but may suppress the expression of genes that are required in the mature photoreceptors. J. Comp. Neurol. 506:584–603, 2008. © 2007 Wiley‐Liss, Inc.
Two‐Photon Absorption Cross‐Sections of Reference Dyes: A Critical Examination
Authors: Chandra Jha Prakash , Wang Yanhua , Ågren Hans
Published: December 2007

The electronic structure and one‐ and two‐photon absorption spectra of four fluorophores, p‐bis(o‐methoxystyryl)benzene (Bis‐MSB), coumarin 307, fluorescein and rhodamine B, commonly used as reference compounds for two‐photon absorption spectra, have been theoretically calculated and compared with available experimental data. The possible reasons for the wide discrepancies in two‐photon absorption cross‐sections reported in the literature are discussed on the basis of the theoretical findings. The role of a solvent environment on the electronic one‐ and two‐photon absorption spectra is also studied. We highlight some necessary precautions that one needs to take when comparing literature results of two‐photon absorption cross‐sections.
Photobleaching in Two‐Photon Scanning Fluorescence Correlation Spectroscopy
Authors: Petrášek Zdeněk , Schwille Petra
Published: December 2007

Two‐photon excitation in fluorescence correlation spectroscopy (FCS) is often preferred to one‐photon excitation because of reduced bulk photobleaching and photodamage, and deeper penetration into scattering media, such as thick biological specimens. Two‐photon FCS, however, suffers from lower signal‐to‐noise ratios which are directly related to the lower molecular brightness achieved. We compare standard FCS with a fixed measurement volume with scanning FCS, where the measurement volume is scanned along a circular path. The experimental results show that photobleaching is the dominant cause of the effects observed at the high excitation powers necessary for good signal‐to‐noise ratios. Theoretical calculations assuming a nonuniform excitation intensity profile, and using the concept of generalized volume contrast, provide an explanation for the photobleaching effects commonly observed in two‐photon FCS at high excitation intensities, without having to assume optical saturation. Scanning alleviates these effects by spreading the photobleaching dose over a larger area, thereby reducing the depletion of fluorescent molecules in the measurement volume. These results, which facilitate understanding of the photobleaching in FCS and of the positive effects of scanning, are particularly important in studies involving the autocorrelation amplitude g(0), such as concentration measurements or binding studies using fluorescence cross‐correlation between two labeled species.
Electrical and Optical Properties of Cetineite‐Type Rb‐, Sr‐, and Ba‐Oxoselenoantimonates(III)
Authors: Sendor Dorota , Fokwa Boniface P. T. , Dronskowski Richard , Simon Ulrich
Published: December 2007

Large single‐crystals of the cetineite‐type phases (Rb;Se), (Sr;Se) and (Ba;Se) have been synthesized by hydrothermal reactions and single‐crystal X‐ray analyses with atomic resolution together with the electrical and optical measurements confirm a trend in the optical gap related to the chemical composition. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Pyrazole‐Bridged NHC Ligands and Their Dimetallic (Allyl)palladium Complexes
Authors: Scheele Ulrich J. , John Michael , Dechert Sebastian , Meyer Franc
Published: December 2007

A set of compartmental pyrazole‐based ligands with appended NHC donors has been synthesized and isolated as [H4L]Cl3 and [H3L](PF6)2 salts. Dinuclear (allyl)palladium complexes of these ligands are conveniently accessible via the in situ prepared silver species. Three complexes [(allyl)2Pd2L]PF6 and one derivative [(methallyl)2Pd2L]PF6 have been characterized crystallographically, which revealed that the metal ions are positioned in close proximity [d(Pd···Pd) = 3.97–4.05 Å], with two possible mutual orientations of the (meth)allyl ligands within the dimetallic pocket. NMR spectroscopy shows slow interconversion of these isomers (k = 0.05–0.4 s–1), where the (meth)allyl ligands are detached trans to the carbene during this η3‐η1‐η3 dynamic process.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Microfluidic chip‐based cell electrophoresis with multipoint laser‐induced fluorescence detection system
Authors: Yu Linfen , Shen Zheng , Mo Jiankun , Dong Xiuling , Qin Jianhua , Lin Bingcheng
Published: December 2007

In this work, the electrophoretic mobility (EPM) measurement of individual cells was investigated by a simple on‐chip electrophoresis system with LIF multipoint detection. The system enabled the characterization of cell electrophoresis behavior as well as the fluorescence signal from individual cells simultaneously. The measurement yielded the electropherograms of a large number of cells labeled with dye, in which the migration time and migration distance could be obtained easily. The EPM has been demonstrated to be different between the K562 cells and K562 cells treated with anticancer drug arsenic trioxide (As2O3). The K562 cells were found to exhibit a lower EPM compared to the cells after drug addition with different concentration. In this preliminary study, over 300 cells could be analyzed within 2 h, demonstrated a much higher analysis throughput compared with traditional methods. The established system is simple and fast, which is expected to be a promising method for evaluating cell surface properties and to be useful in clinical and pharmaceutical applications.
Electrodeless direct current dielectrophoresis using reconfigurable field‐shaping oil barriers
Authors: Thwar Prasanna K. , Linderman Jennifer J. , Burns Mark A.
Published: December 2007

We demonstrate dielectrophoretic (DEP) potential wells using pairs of insulating oil menisci to shape the DC electric field. These oil menisci are arranged in a configuration similar to the quadrupolar electrodes, typically used in DEP, and are shown to produce similar field gradients. While the one‐pair well produces a focusing effect on particles in flow, the two‐pair well results in creating spatial traps against crossflows. Uncharged polystyrene particles were used to map the DEP force fields and the experimental observations were compared against the field profiles obtained by numerically solving Maxwell's equations. We demonstrate trapping of a single particle due to negative DEP against a pressure‐driven crossflow. This can be easily extended to trap and hold cells and other objects against flow for a longer time. We also show the results of particle trapping experiments performed to observe the effect of adjusting the oil menisci and the gap between two pairs of menisci in a four‐menisci configuration on the nature of the DEP well formed at the center. A design parameter, Θ, capturing the dimensions of the DEP energy well, is defined and simulations exploring the effects of different geometric features on Θ are presented.
The locally conservative Galerkin (LCG) method for solving the incompressible Navier–Stokes equations
Authors: Thomas C. G. , Nithiarasu P. , Bevan R. L. T.
Published: December 2007

In this paper, the locally conservative Galerkin (LCG) method (Numer. Heat Transfer B Fundam. 2004; 46:357–370; Int. J. Numer. Methods Eng. 2007) has been extended to solve the incompressible Navier–Stokes equations. A new correction term is also incorporated to make the formulation to give identical results to that of the continuous Galerkin (CG) method. In addition to ensuring element‐by‐element conservation, the method also allows solution of the governing equations over individual elements, independent of the neighbouring elements. This is achieved within the CG framework by breaking the domain into elemental sub‐domains. Although this allows discontinuous trial function field, we have carried out the formulation using the continuous trial function space as the basis. Thus, the changes in the existing CFD codes are kept to a minimum. The edge fluxes, establishing the continuity between neighbouring elements, are calculated via a post‐processing step during the time‐stepping operation. Therefore, the employed formulation needs to be carried out using either a time‐stepping or an equivalent iterative scheme that allows post‐processing of fluxes. The time‐stepping algorithm employed in this paper is based on the characteristic‐based split (CBS) scheme. Both steady‐ and unsteady‐state examples presented show that the element‐by‐element formulation employed is accurate and robust. Copyright © 2007 John Wiley & Sons, Ltd.
High‐order 𝒞1 finite‐element interpolating schemes—Part I: Semi‐Lagrangian linear advection
Authors: Djoumna G. , Pierre R. , Le Roux D. Y.
Published: December 2007

This paper is devoted to the development of accurate high‐order interpolating schemes for semi‐Lagrangian advection. The characteristic‐Galerkin formulation is obtained by using a semi‐Lagrangian temporal discretization of the total derivative. The semi‐Lagrangian method requires high‐order interpolators for accuracy. A class of 𝒞1 finite‐element interpolating schemes is developed and two semi‐Lagrangian methods are considered by tracking the feet of the characteristic lines either from the interpolation or from the integration nodes. Numerical stability and analytical results quantifying the amount of artificial viscosity induced by the two methods are presented in the case of the one‐dimensional linear advection equation, based on the modified equation approach. Results of test problems to simulate the linear advection of a cosine hill illustrate the performance of the proposed approach. Copyright © 2007 John Wiley & Sons, Ltd.
A comparison of solvers for quadratic eigenvalue problems from combustion
Authors: Sensiau C. , Nicoud F. , van Gijzen M. , van Leeuwen J. W.
Published: December 2007

Two iterative subspace methods (Arnoldi and Jacobi–Davidson) are compared for solving typical quadratic eigenvalue problems arising when studying combustion instabilities. An academic, representative test case is presented with associated analytical solution. The efficiency of the iterative methods is studied in terms of running time when 1–10 eigenpairs are sought for, the computational domain being discretized with 500–32 000‐node finite element meshes. The sensitivity of the methods to the dimension of the search subspace is also investigated. Copyright © 2007 John Wiley & Sons, Ltd.
A fully implicit, mass‐conserving, semi‐Lagrangian scheme for the f‐plane shallow‐water equations
Authors: Thuburn J.
Published: December 2007

A fully implicit, mass‐conserving, semi‐Lagrangian discretization of the shallow‐water equations on a doubly periodic f‐plane is proposed. The scheme requires the solution of a nonlinear and nonlocal system of equations at each time step. When a Newton method is used to solve this system of equations, a partial elimination of the unknowns can be carried out to leave a near standard elliptic problem at each Newton iteration, for which efficient solution methods are well known. Moreover, the nonlinearity is, in fact, rather weak so that a small number of Newton iterations (1–3) should be sufficient for practical application.

Setting up the Newton method and solving the resulting elliptic problem can be made cheaper by making certain approximations to the terms in the Jacobian matrix; the price to pay is a slowing of the Newton convergence rate. Numerical experiments are carried out to quantify the effects on convergence rate of such approximations to help decide the optimum trade‐off between cost per Newton iteration and iteration count. Copyright © 2007 John Wiley & Sons, Ltd.
Practical considerations in the use of polarized light microscopy in the analysis of the collagen network in articular cartilage
Authors: Rieppo Jarno , Hallikainen Jarmo , Jurvelin Jukka S. , Kiviranta Ilkka , Helminen Heikki J. , Hyttinen Mika M.
Published: December 2007

Polarized light microscopy is a traditional method for visualizing the collagen network architecture of articular cartilage. Articular cartilage repair and tissue engineering studies have raised new demands for techniques capable of quantitative characterization of the scar and repair tissues, including properties of the collagen network. Modern polarized light microscopy can be used to measure collagen fibril orientation, parallelism, and birefringence. New commercial instruments are computer controlled and the measurements are easy to perform. However, often the interpretation of results causes difficulties, even errors, because the theoretical aspects of the technique are demanding. The aim of this study was to describe the instrumentation and properties of a modern polarized light microscope, to point out some sources of error in the interpretation of the results, and to recall the theoretical background of the polarized light microscopy. Microsc. Res. Tech., 2008. © 2007 Wiley‐Liss, Inc.
Characterization of Antarctic psychrotrophic bacteria with antibacterial activities against terrestrial microorganisms
Authors: Lo Giudice Angelina , Bruni Vivia , Michaud Luigi
Published: December 2007

Five‐hundreds and eighty bacterial strains, isolated from various Antarctic marine sources and locations, were screened for antimicrobial activity against terrestrial microorganisms. Twenty‐two Antarctic isolates (3.8%), mainly retrieved from the water column at Terra Nova Bay (Ross Sea), expressed antagonistic activity against one to three indicator organisms. Escherichia coli and Proteus mirabilis resulted as the more susceptible, followed by Micrococcus luteus and Bacillus subtilis. None of the isolates inhibited the growth of Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella enterica and the eukaryotic fungus Candida albicans.

Active Antarctic isolates, identified by 16S rDNA sequencing and phenotypically characterized by classical methods, were phylogenetically affiliated to the Actinobacteria (16 strains) and the γ‐Proteobacteria (6 strains). Inhibition patterns, as well as phenotypic characteristics, highly vary for different isolates, even though they were affiliated to the same genus or closely related to the identical microorganism retrieved from the database, suggesting that these features were more likely strain‐rather than species‐specific.

Results obtained from the present study confirm previous observations and highlight the potentiality of Antarctic marine bacteria as novel source of antibacterial substances. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
PAM‐Microfabricated Polyurethane Scaffolds: in vivo and in vitro Preliminary Studies
Authors: Vozzi Giovanni , Rechichi Alfonsina , Dini Francesca , Salvadori Claudia , Vozzi Federico , Burchielli Silvia , Carlucci Fabio , Arispici Mario , Ciardelli Gianluca , Giusti Paolo , Ahluwalia Arti
Published: December 2007

Polymeric scaffolds were realised with linear degradable PU in the form of square, hexagonal and octagonal grids. They were characterised in terms of their mechanical properties. Analysis shows that the mechanical properties of the scaffolds depend on their geometries which are easily modulated using PAM. In vitro biological assays showed that PU promotes the adhesion and proliferation of fibroblast cells and that cell activities are better on PU scaffolds than on PU films. In vivo implantation of PU and PLGA scaffolds and PU films demonstrated that the scaffolds are completely resorbed after three months with a slight inflammatory response, while the PU film was still present after six months with an intense granulomatous reaction.

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Optimizing periodic inspections in chemical plants by corrosion monitoring
Authors: Winkelmans M. , Müller U. , Bassler H.‐J.
Published: December 2007

An efficient industrial corrosion monitoring system would give information about the corrosion activity and corrosion damage of critical components within a chemical plant in real time. A research project to develop an industrial tool for the simultaneous monitoring of general and localized corrosion was initiated. General and localized corrosion can be monitored by combining several non‐destructive techniques.

An industrial probe for corrosion monitoring is an excellent tool for an intelligent material selection, to identify critical process conditions or to optimize the use of corrosion inhibitors.

The highest added value of an industrial tool for corrosion monitoring is its capacity to optimize periodic inspections.
Use of the wavelet method for analyzing electrochemical noise data
Authors: Duran O. , Vera E. , Ortiz C. A. , Heyn A.
Published: December 2007

This research paper shows the application of the mathematical tool “wavelet's” to be used in the interpretation and analysis of electrochemical noise signals. The Fast Fourier Transformation (FFT) is one of the most commonly used techniques for analyzing electrochemical noise. But the application of this methodology to the analysis of stochastic signals does not allow their interpretation in a suitable way. The wavelet's methodology carries out the analysis by means of the construction of finite base functions. In several studies, it has been found out that the function that is closest to the electrochemical oscillations is the one called “coiflets,” which presents a similar geometry to what it is observed when an ionic–electronic interchange occurs during an electrochemical interphase. The analysis that appears here was implemented using the toolbox “LabView™.”
Aliphatic Polyesters of Butyne‐1,4‐Diol
Authors: Kricheldorf Hans R. , Gao Quinwei , Buzin Pavel , Schwarz Gert
Published: December 2007

Polyesters of butyne‐1,4‐diol (ByD) and aliphatic dicarboxylic acids (ADAs) were prepared in three different ways. Method I is based on the transesterification of ByD with the dimethyl esters of ADAs in bulk. Although catalyst and temperature were varied, only oligomers were obtained, because even at 220 °C the conversions were far from complete. Higher molar masses resulted from method II, the acid‐catalyzed polycondensation of ByD with sebacic acid, but this method yielded a high fraction of ether groups. The best results were obtained from method III, which consisted of pyridine‐catalyzed polycondensations of ByD and various ADA dichlorides at 0–20 °C. SEC measurements yielded corrected number average molecular weights ($\overline M _{\rm n}$) up to 20 000 Da. The success of this method depended largely on the excess of the ADA dichloride in the feed ratio. MALDI‐TOF mass spectrometry evidenced that under optimized reaction conditions the chain‐growth was mainly limited by cyclization. With the exception of the polysuccinate, all polyesters were rapidly crystallized materials with melting temperatures in the range of 50–90 °C.

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Freezing of gait and executive functions in patients with Parkinson's disease
Authors: Amboni Marianna , Cozzolino Autilia , Longo Katia , Picillo Marina , Barone Paolo
Published: December 2007

Freezing of gait (FOG) is a frequent, disabling symptom of Parkinson's disease (PD). FOG usually lasts a few seconds. It refers to brief paroxysmal events during which a subject is unable to start or continue locomotion. Despite its frequency, FOG pathophysiology is unclear. Because a frontal lobe dysfunction or a disconnection between the frontal lobe and basal ganglia has been implicated in FOG, we explored frontal functions in PD patients using neuropsychological tests. Thirteen early‐stage PD patients [Hoehn & Yahr score (H&Y) ≤ 2.5] with freezing during “on ” state (FOG+), and 15 age‐, H&Y score‐, and disease‐duration‐matched PD patients without freezing (FOG−) were investigated. No patient was demented or depressed. Assessment included the Unified Parkinson's Disease Rating Scale (UPDRS), FOG questionnaire, Mini Mental State Examination (MMSE), frontal assessment battery (FAB), phonemic verbal fluency, Stroop test (parts II and III), and ten‐point clock test (TPCT). UPDRS and MMSE scores did not differ between the two groups. FAB, verbal fluency, and TPCT scores were significantly lower in FOG+ patients than in FOG− patients (FAB: P = 0.008; phonemic verbal fluency: P = 0.011; TPCT: P = 0.024). FOG correlated with lower scores at frontal tests in patients with early‐stage PD. © 2007 Movement Disorder Society
The development of duodenal microadenomas in FAP patients: the human correlate of the Min mouse
Authors: Preston SL , Leedham SJ , Oukrif D , Deheregoda M , Goodlad RA , Poulsom R , Alison MR , Wright NA , Novelli M
Published: December 2007

The morphological changes associated with the adenoma‐carcinoma sequence are well documented in the colorectum. Small intestinal carcinogenesis is thought to progress through a similar adenoma‐to‐carcinoma pathway, but there is a relative dearth of studies examining the associated morphological changes. The best‐known mouse model of intestinal neoplasia, the multiple intestinal neoplasia (Min) mouse, has been criticized as a genetic model of intestinal neoplasia, as the majority of its tumours occur in the small intestine. We examined pancreatico‐duodenal resection specimens from seven familial adenomatous polyposis (FAP) patients. Serial sections of these were stained with haematoxylin and eosin for β‐catenin and its downstream target CD44, for BMPR1a, lysozyme, carbonic anhydrase II, and with MIB‐1. Individual dysplastic crypts were isolated and mutations in the FAP (APC) gene compared between the top and bottom of the crypt. We found that: (a) duodenal microadenomas are extremely common in FAP patients; (b) these grow in the core of duodenal villi, forming lesions similar to those described in the Min mouse; (c) many lesions arise as monocryptal adenomas and grow by a process of crypt fission and branching; (d) migrating adenomatous cells lose their dysplastic phenotype as they migrate up the crypt villous axis; and (e) Paneth cells lose positional information. In conclusion: (a) the morphological similarity of adenomas in the Min mouse and human suggest the Min mouse is a good model of FAP; (b) duodenal adenomas in FAP originate in monocryptal adenomas and follow the ‘bottom‐up’ rather than the ‘top‐down’ model of morphogenesis; (c) early microadenomas show evidence of cellular differentiation; (d) defects in the positioning of Paneth cells suggests disruption of the EphB2:EphB3 receptor system. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Suitability of two laboratory testing methods to evaluate the side effects of pesticides on Typhlodromus pyri Scheuten (Acari: Phytoseiidae)
Authors: Bonafos Romain , Auger Philippe , Guichou Sabine , Kreiter Serge
Published: December 2007

BACKGROUND: Laboratory results of the French ANPP/CEB guideline No. 167 and IOBC/WPRS Ring Testing Group methods for testing the side effects of pesticides on the predatory mite Typhlodromus pyri Scheuten were compared with respect to their suitability to evaluate the toxicity of three pesticides.

RESULTS: Results obtained with the ANPP/CEB guideline allow the demonstration of significant differences between two slightly toxic products, a dichlofluanid 500 g kg−1 kWP (Euparen® 50WP) and a quinoxyfen 250 g L−1 SCC (Legend®), and a highly toxic cymoxanil 60/mancozeb 200/folpet 275 g kg−1 WP [Remiltine F Pepite® (RFP)], on the basis of bioassays conducted in the laboratory. In contrast, results obtained with the IOBC/WPRS method classified all three as harmful.

CONCLUSION: The evaluation of the toxicity of RFP revealed that the concentration, the quantity of the wet deposit and the food source used in the IOBC/WPRS method maximise the toxicity, in comparison with those used in the ANPP/CEB protocol. Valid criteria in controls were all respected in the ANPP/CEB tests but not in the IOBC/WPRS samples. This result revealed difficulties related to the use of the IOBC/WPRS method in laboratories. Copyright © 2007 Society of Chemical Industry
The dependence of luminescence lifetimes on additive irradiation in natural sedimentary quartz: sands from Santa Elina, Brazil
Authors: Chithambo M. L. , Ogundare F. O. , Feathers J. , Hong D. G.
Published: December 2007

Time‐resolved luminescence and its component lifetimes have been measured from natural quartz in order to interpret the associated dynamics of luminescence emission. The influence of beta irradiation, and measurement temperature on the lifetimes have been investigated and parameters of the kinetics involved calculated. The results are explained by considering the extent of non‐radiative processes and the role of charge transfer between several types of luminescence centres. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
IV and CV measurements of Schottky diodes deposited on Ge by electron beam and sputter deposition
Authors: Coelho S. M. M. , Auret F. D. , Janse van Rensberg P. J. , Nyamhere C. , Nel J. M. , Hayes M.
Published: December 2007

Various Schottky metal contacts were deposited on bulk grown (111) Sb‐doped n‐type Germanium. The Schottky contacts were deposited by resistive evaporation, electron beam deposition and RF sputter deposition. Current–voltage (IV) and capacitance–voltage (CV) measurements revealed differences in the diode performance that suggested damage caused to the germanium semiconductor crystal by the more energetic deposition methods of electron beam deposition and sputter deposition. Subsequent annealing improved the diode performance thus succeeding in removing some of the defects introduced, but not all. Sputter deposition produced the poorest diodes highlighting this as the most damaging process. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Evaluation of exchange‐correlation functionals in comparison to B3LYP for the description of silicon and Cu‐doped silicon clusters
Authors: Dkhissi Ahmed
Published: December 2007

Several developed exchange‐correlation functionals in density functional theory have been systematically applied to describe the geometries and electronic properties of small silicon (Sin+1, n < 5) and doped silicon (CuSin) clusters. The performance of the various approaches is done with their critical comparison with B3LYP and available high level wave function methods. Our calculations indicate that all functional give reasonable results. Further, OLYP/6‐311+G* approach generally agrees with B3LYP results. The good performance of OLYP is of significant interest knowing that the hybrid functionals are computationally more demanding than nonhybrid schemes. So, we recommend OLYP/6‐311+G* approach for studying the doped silicon clusters and understanding the electronic properties of silicon by the presence of doped metal impurities. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
The philosophical dimension to the principle of sustainable development in the Polish scientific literature
Authors: Papuziński Andrzej
Published: December 2007

The main philosophical dimensions to discourse on sustainable development are presented. They are concerned with such issues as the specific nature of this discourse vis‐à‐vis the cognitive perspectives of the social and economic sciences; the philosophical principles underpinning sustainable development; philosophical conceptualizations of sustainable development and a typology thereof (in line with ontological, anthropological, axiological and historiosophical criteria) and philosophical issues in sustainable development (quality of life, justice, rationality, progress and utopia). The article also considers the need for philosophical research on sustainable development, ways of understanding the concept of the sustainable development philosophy (including the need to construct this type of concept) and the sense in implementing the sustainable development project as a further version of enlightened social philosophy. Copyright © 2007 John Wiley & Sons, Ltd and ERP Environment.
Two-State Dynamics for Replicating Two-Strand Systems
Authors: Aerts Diederik , Czachor Marek
Published: December 2007

We propose a formalism for describing two-strand systems of a DNA type by means of soliton von Neumann equations, and illustrate how it works on a simple example exactly solvably by a Darboux transformation. The main idea behind the construction is the link between solutions of von Neumann equations and entangled states of systems consisting of two subsystems evolving in time in opposite directions. Such a time evolution has analogies in realistic DNA where the polymerazes move on leading and lagging strands in opposite directions.