bluuebunny/crossref_metadata_2025 huggingface dataset:
Defining and optimizing algorithms for neighbouring particle identification in SPH fluid simulations
Authors: Viccione G. , Bovolin V. , Carratelli E. Pugliese
Published: March 2008

Lagrangian particle methods such as smoothed particle hydrodynamics (SPH) are very demanding in terms of computing time for large domains. Since the numerical integration of the governing equations is only carried out for each particle on a restricted number of neighbouring ones located inside a cut‐off radius rc, a substantial part of the computational burden depends on the actual search procedure; it is therefore vital that efficient methods are adopted for such a search.

The cut‐off radius is indeed much lower than the typical domain's size; hence, the number of neighbouring particles is only a little fraction of the total number. Straightforward determination of which particles are inside the interaction range requires the computation of all pair‐wise distances, a procedure whose computational time would be unpractical or totally impossible for large problems.

Two main strategies have been developed in the past in order to reduce the unnecessary computation of distances: the first based on dynamically storing each particle's neighbourhood list (Verlet list) and the second based on a framework of fixed cells.

The paper presents the results of a numerical sensitivity study on the efficiency of the two procedures as a function of such parameters as the Verlet size and the cell dimensions. An insight is given into the relative computational burden; a discussion of the relative merits of the different approaches is also given and some suggestions are provided on the computational and data structure of the neighbourhood search part of SPH codes. Copyright © 2008 John Wiley & Sons, Ltd.
A continuous adjoint formulation for the computation of topological and surface sensitivities of ducted flows
Authors: Othmer C.
Published: March 2008

Topology optimization of fluid dynamic systems is a comparatively young optimal design technique. Its central ingredient is the computation of topological sensitivity maps. Whereas, for finite element solvers, implementations of such sensitivity maps have been accomplished in the past, this study focuses on providing this functionality within a professional finite volume computational fluid dynamics solver. On the basis of a continuous adjoint formulation, we derive the adjoint equations and the boundary conditions for typical cost functions of ducted flows and present first results for two‐ and three‐dimensional geometries. Emphasis is placed on the versatility of our approach with respect to changes in the objective function. We further demonstrate that surface sensitivity maps can also be computed with the implemented functionality and establish their connection with topological sensitivities. Copyright © 2008 John Wiley & Sons, Ltd.
Simple association analysis combining data from trios/sibships and unrelated controls
Authors: Chen Yi‐Hau , Lin Hui‐Wen
Published: March 2008

We consider genetic association analysis that combines data from case‐parent trios/sibships and unrelated controls. A general and simple methodology is proposed, using a weighted least‐squares approach to combine separate information from the case‐parent/case‐sibling analysis and the case‐unrelated control analysis. The new proposal improves over the existing methods in that it requires no assumptions and estimation on the mating‐type distribution. Simulation results show that the new method competes well with the likelihood‐based method when the latter is applicable, and achieves substantial power gains over separate analyses in general. Therefore, the proposed combined association analysis can enjoy wide applications, including the multiallele/locus, haplotype, and genome‐wide association studies. Genet. Epidemiol. 2008. © 2008 Wiley‐Liss, Inc.
Xanthohumol inhibits inflammatory factor production and angiogenesis in breast cancer xenografts
Authors: Monteiro Rosário , Calhau Conceição , Silva Artur Oliveira e , Pinheiro‐Silva Sandra , Guerreiro Susana , Gärtner Fátima , Azevedo Isabel , Soares Raquel
Published: March 2008

Xanthohumol (XN), a natural polyphenol present in beer, is known to exert anti‐cancer effects. However, its precise mechanisms are not yet clearly defined. The aim of this study was to investigate the effect of oral administration of XN in breast cancer xenografts in nude mice. Proliferation and apoptosis were first examined in MCF7 cell cultures after incubation with XN by trypan blue exclusion assay, [3H]‐thymidine incorporation, KI67 immunostaining and TUNEL. Morphological and histological characteristics of tumours from XN‐treated or control (vehicle‐treated) mice were compared. Immunohistochemistry for proliferative, inflammatory and endothelial cell markers was performed and activation of nuclear factor kappa B (NFκB) pathway was assessed by ELISA. In vitro MCF7 cell proliferation decreased in a dose‐dependent manner. Oral administration of XN to nude mice inoculated with MCF7 cells resulted in central necrosis within tumours, reduced inflammatory cell number, focal proliferation areas, increased percentage of apoptotic cells and decreased microvessel density. Anti‐angiogenic effects of XN were further confirmed by immunoblotting for factor VIII expression in XN‐treated tumours as compared to controls. Decreased immunostaining for NFκB, phosphorylated‐inhibitor of kappa B and interleukin‐1β were also observed as well as a significant decrease in NFκB activity to 60% of control values. These novel findings indicate that XN is able to target both breast cancer and host cells, namely inflammatory and endothelial cells, suggesting its potential use as a double‐edge anti‐cancer agent. J. Cell. Biochem. 104: 1699–1707, 2008. © 2008 Wiley‐Liss, Inc.
The effects of erdosteine, N‐acetylcysteine, and vitamin E on nicotine‐induced apoptosis of hippocampal neural cells
Authors: Demiralay Rezan , Gürsan Nesrin , Erdem Havva
Published: March 2008

This study investigated the frequency of apoptosis in rat hippocampal neural cells after intraperitoneal nicotine injection, examining the roles of the inflammatory markers myeloperoxidase (MPO) and tumor necrosis factor alpha (TNF‐α) in nicotine‐induced brain damage and the protective effects of three known antioxidant agents, N‐acetylcysteine (NAC), erdosteine, and vitamin E. Female Wistar rats were divided into seven groups, each composed of nine rats: 2 negative control groups, 2 positive control groups, one erdosteine‐treated group (500 mg/kg), one NAC‐treated group (500 mg/kg), and one vitamin E‐treated group (500 mg/kg). Nicotine was intraperitoneally injected at a dosage of 0.6 mg/kg for 21 days. Following nicotine injection, the antioxidants were administered orally; treatment was continued until the rats were killed. Apoptosis level in hippocampal neural cells was determined by using TUNEL (terminal deoxynucleotidyl transferase‐mediated dUTP nick endlabeling) method. Staining of cytoplasmic TNF‐α in hippocampal neural cells and hippocampus MPO activity were evaluated by immunohistochemistry. Nicotine administration had no effect on local TNF‐α production, or hippocampal MPO activity. The treatments with erdosteine, NAC and vitamin E significantly reduced the rate of nicotine‐induced hippocampal neural cell apoptosis. This findings suggest that erdosteine and NAC can be as effective as vitamin E in protecting against nicotine‐induced hippocampal neural cell apoptosis. J. Cell. Biochem. 104: 1740–1746, 2008. © 2008 Wiley‐Liss, Inc.
Differential regulation of HSP70 expression by the JNK kinases SEK1 and MKK7 in mouse embryonic stem cells treated with cadmium
Authors: Nishitai Gen , Matsuoka Masato
Published: March 2008

JNK, a member of the mitogen‐activated protein kinases (MAPKs), is activated by the MAPK kinases SEK1 and MKK7 in response to environmental stresses. In the present study, the effects of CdCl2 treatment on MAPK phosphorylation and HSP70 expression were examined in mouse embryonic stem (ES) cells lacking the sek1 gene, the mkk7 gene, or both. Following CdCl2 exposure, the phosphorylation of JNK, p38, and ERK was suppressed in sek1−/− mkk7−/− cells. When sek1−/− or mkk7−/− cells were treated with CdCl2, JNK phosphorylation, but not the phosphorylation of either p38 or ERK, was markedly reduced, while a weak reduction in p38 phosphorylation was observed in sek1−/− cells. Thus, both SEK1 and MKK7 are required for JNK phosphorylation, whereas their role in p38 and ERK phosphorylation could overlap with that of another kinase. We also observed that CdCl2‐induced HSP70 expression was abolished in sek1−/− mkk7−/− cells, was reduced in sek1−/− cells, and was enhanced in mkk7−/− cells. Similarly, the phosphorylation of heat shock factor 1 (HSF1) was decreased in sek1−/− mkk7−/− and sek1−/− cells, but was increased in mkk7−/− cells. Transfection with siRNA specific for JNK1, JNK2, p38α, ERK1, or ERK2 suppressed CdCl2‐induced HSP70 expression. In contrast, silencing of p38β or p38γ resulted in further accumulation of HSP70 protein. These results suggest that HSP70 expression is up‐regulated by SEK1 and down‐regulated by MKK7 through distinct MAPK isoforms in mouse ES cells treated with CdCl2. J. Cell. Biochem. 104: 1771–1780, 2008. © 2008 Wiley‐Liss, Inc.
JNK modulates the effect of caspases and NF‐κB in the TNF‐α‐induced down‐regulation of Na+/K+ATPase in HepG2 cells
Authors: Kassardjian Ari , Kreydiyyeh Sawsan Ibrahim
Published: March 2008

An inhibition of the Na+/K+ATPase was previously shown to accompany and potentiate apoptosis in different experimental models. Since TNF‐α is known to be a pro and anti‐apoptotic cytokine, this work was undertaken to study the effect of TNF‐α on the Na+/K+ATPase in HepG2 cells and to determine the signaling pathway involved. Cells were incubated for 1 h with TNF‐α in presence and absence of PDTC, SP600125 and FK009, respective inhibitors of NF‐KB, c‐JNK, and caspases. The activity of the pump was assayed by measuring the ouabain‐inhibitable release of inorganic phosphate, and changes in its expression were monitored by western blot analysis. TNF‐α decreased significantly the activity and protein expression of the Na+/K+ATPase. NF‐κB and caspases were found to be the main effectors of the cytokine, mediating respectively down‐regulation and up‐regulation of the pump. Their activity was however modulated at 1 h by c‐JNK, which stimulated the caspases and inhibited NF‐κB, resulting in a net inhibition of the ATPase, and probably favoring the apoptotic pathway. J. Cell. Physiol. 216: 615–620, 2008, © 2008 Wiley‐Liss, Inc.
High‐pressure Raman spectroscopy study of α and γ polymorphs of AlH3
Authors: Tkacz Marek , Palasyuk Taras , Graetz Jason , Saxena Surendra
Published: March 2008

For the first time, Raman spectroscopy of α and γ polymorphs of AlH3 has been performed in the pressure range from ambient up to 16.9 and 32.7 GPa, respectively using the diamond anvil cell (DAC) technique. An analysis of pressure response wavenumbers (ν) for α‐AlH3 showed a change of dνi/dP at a pressure of about 8 GPa and may indicate a monoclinic distortion from the initially hexagonal α‐AlH3. The distortion is stable at least up to 16.9 GPa. The γ form exhibited more complex behavior transforming to the α form at a pressure of about 12 GPa. The structural phase transition was shown to be an irreversible and kinetically slow process that required at least 5 h to complete. Copyright © 2008 John Wiley & Sons, Ltd.
Erratum: Prehistoric dental disease and the dietary shift from cactus to cultigens in northwest Mexico
Authors: Watson J. T.
Published: March 2008

The original article to which this erratum refers was published in International Journal of Osteoarchaeology Volume 18 Issue No. 2, pages 202–212. Copyright © 2008 John Wiley & Sons, Ltd.
Preparation and properties of dipropargyl ether of bisphenol A‐modified bismaleimide resins and composites
Authors: Rong Zhuxia , Huang Fuwei , Shen Xuening , Huang Farong
Published: March 2008

A kind of modified bismaleimide resin, with good heat resistance and processing properties for advanced composites, was developed. The modifier, dipropargyl ether of bisphenol A (DPBPA), was prepared by a phase‐transfer catalyzing procedure, characterized by FTIR, 1H NMR, and elementary analysis, and used to modify 4,4′‐bismaleimidodiphenylmethane (BMDPM). The thermopolymerization of a DPBPA‐modified BMDPM resin was followed up by FTIR. The curing of the resin was investigated by differential scanning calorimeter and gelation characterization. The relation of viscosity and temperature was used to characterize the processability of the resin. The results of DMA analysis showed that the cured DPBPA‐modified BMDPM resins had a glass transition temperature higher than 320°C. The carbon fiber (T700) reinforced composites showed excellent flexural properties at ambient temperature and at 250°C. DPBPA could effectively improve mechanical properties without deteriorating heat resistance of the BMDPM resin a lot. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Effect of γ‐irradiation on the physical properties and dyeability of poly(vinyl butyral) blends with polystyrene and poly(ethylene glycol)
Authors: Nizam El‐Din Horia M. , El‐Naggar Abdel Wahab M.
Published: March 2008

Cast films of polymer blends essentially based on poly(vinyl butyral) (PVB) and equal ratios of polystyrene (PS) and poly(ethylene glycol) (PEG) were prepared from benzene and butyl alcohol solutions of the individual polymers. The effect of γ‐irradiation on the thermal decomposition and tensile mechanical properties was investigated. Moreover, the effect of γ‐irradiation on the dye affinity of PVB/PS and PVB/PEG for basic and acid dyestuffs was studied. The thermogravimetric analysis (TGA) study showed that the unirradiated PVB polymer films prepared in benzene displayed higher thermal stability than the same polymer films prepared in butanol. However, in all cases the thermal stability was found to increase with increasing γ‐irradiation dose. On the other hand, PVB/PS blend possesses higher thermal stability than PVB/PEG, as shown from the determination of the weight loss (%) at different heating temperatures, the temperatures of the maximum rate of reaction and the activation energy. While, pure PS films showed the stress‐strain behavior of brittle polymers, PVB/PS films showed the behavior of tough polymers with yielding properties. The results of dyeing clearly showed that the solvent type, blend composition, and irradiation dose are determining factors for the dye affinity for basic or acid dyes. For example, unirradiated PVB films prepared from butanol displayed a higher affinity for the basic and acid dyes than the same polymer prepared from the same benzene. However, PVB prepared from butanol showed higher affinity to the dyes than PS prepared from the same solvent. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Modification of asphalt by packaging waste‐polyethylene
Authors: Fang Changqing , Li Tiehu , Zhang Zengping , Jing Deqi
Published: March 2008

The “white pollution” made of packaging waste polymers and its recycling has become a common issue. In this article, the retrieved waste milk‐packing bag (its main ingredients was polyethylene) was selected to modify the ordinary oil asphalt. Asphalt was modified with 1, 3, 6, and 9 wt% content of waste‐polyethylene. The results showed that the softening point and the freeze‐to‐crack stress of asphalt increased the penetration and the freeze‐to‐crack temperature decreased after modification. The comprehensive performance of raw asphalt improved noticeably. Infrared analysis suggests that waste‐polyethylene in packaging (WPE) combines the matrix of asphalt through physical mixture modification. And the modification mechanism of WPE was studied by the analysis of its micro structure, the characteristics of WPE, the effects of Crack pinning and Silver Shear yield in the decentralized process. Using waste packaging polymers to modify the asphalt proved to be an ideal way, for not only solving the problem of “white pollution”, but also for improving the performance of asphalt. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Investigation of flow properties of asphalt binders containing polymer modifiers
Authors: Nien Yu‐Hsun , Yeh Pei‐Hung , Chen Wei‐Chyum , Liu Wen‐Tsung , Chen Jean‐Hong
Published: March 2008

Modified asphalts using polymeric additives, including isotactic polypropylene (iPP) and different degrees of chlorinated polypropylene (CPP), have been prepared and examined using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), rotational viscometer, and dynamic shear rheometer (DSR) in this study. The results of DSC studies show that different levels of the crystallization occur in asphalt/iPP blends because most of the crystallinity of iPP remain intact in the blend, while those asphalt samples having CPP tend to affect the thermal behavior in the DSC thermograms because of increasing the amorphous region of CPP. From the images of SEM, the distinctions of the phase distributions between the asphalt/iPP and asphalt/CPP blends illustrate that the chlorine content in CPP is a significant factor in controlling its compatibility with asphalt. The rheological studies show that the asphalt blends containing CPP (26 wt% of Cl) exhibit higher viscosity in terms of higher temperature to get Newtonian behavior and display superior rutting resistance to avoid permanent deformation at high temperature. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Synthesis and characterization of graft copolymers of ethyl acrylate/acrylamide mixtures onto starch
Authors: Zhang Bin , Zhou Yongyuan
Published: March 2008

Graft copolymerization of ethyl acrylate/acrylamide onto corn starch using potassium permanganate–citric acid initiation system was investigated. Major factors affecting the polymerization reaction were thoroughly investigated in terms of initiator concentration, monomer concentration, polymerization time, polymerization temperature, and starch/liquor, and the obtained results implied that the polymer yield which were expressed by total monomer conversion, grafting ratio, and grafting efficiency were determined by these factors. The optimum reaction conditions were as follows: starch, 30 g; potassium permanganate (based on weight of starch), 0.1%; citric acid (based on weight of starch), 0.5%; ethyl acrylate, 20%; acrylamide, 0.4 g; time, 3 h; temperature, 40°C; starch/liquor, 1:3. We concluded that the initiator of potassium permanganate–citric acid system could be used as a cheap initiator in manufacturing the starch graft copolymer. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Effects of crosslinking density on structure and properties of interpenetrating polymer networks from polyurethane and nitroguar gum
Authors: Fan Qingchun , Xiao Chaobo
Published: March 2008

Semi‐interpenetrating polymer networks (semi‐IPNs) of castor oil‐based polyurethane prepolymer and nitroguar gum (NGG) with different crosslinking density of the PU network, coded as UNG films, were prepared through varying the trimethanol propane (TMP)/1,4‐butanediol (BDO) molar ratios in the chain extender mixture. The effects of crosslinking density on the structure and properties of the UNG films was investigated by attenuated total reflection Fourier transform infrared spectroscopy, differential scanning calorimetry, dynamic mechanical thermal analysis, scanning electron microscopy, crosslinking density measurements, solvent‐extracting tests, and tensile tests. The experimental results revealed that incorporation of TMP crosslinker into the hard segments of polyurethane resulted in a decrease in the aggregation of hard segments. With an increase of the TMP/BDO molar ratios, the semi‐IPN films exhibited the higher crosslinking density, glass temperature (Tg), stiffness, and tensile strength (σb). Furthermore, the experimental results also indicated that NGG restricted the formation of crosslinking networks when the TMP content is relatively high, which led to the negative deviation of the theoretically predicted crosslinking density and Dibenedetto's equation. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Reverse ATRP process of acrylonitrile in the presence of ionic liquids
Authors: Hou Chen , Qu Rongjun , Ji Chunnuan , Sun Changmei , Wang Chunhua
Published: March 2008

An ionic liquid, 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([C4mim] [BF4]), was first used as the solvent in azobisisobutyronitrile (AIBN)‐initiated reverse atom transfer radical polymerization (RATRP) of acrylonitrile with FeCl3/succinic acid (SA) as the catalyst system. The polymerization in [C4mim][BF4] proceeded in a well‐controlled manner as evidenced by kinetic studies. Compared with the polymerization in bulk, the polymerization in [C4mim][BF4] not only showed the best control of molecular weight and its distribution but also provided rather rapid reaction rate with the ratio of [C4mim][BF4] at 200:1:2:4. The polymerization apparent activation energies in [C4mim][BF4] and bulk were calculated to be 48.2 and 55.7 kJ mol−1, respectively. Polyacrylonitrile obtained was successfully used as a macroinitiator to proceed the chain extension polymerization in [C4mim][BF4] via a conventional ATRP process. [C4mim][BF4] and the catalyst system could be easily recycled and reused after simple purification and had no effect on the living nature of polymerization. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2701–2707, 2008
Novel hepatoma‐targeting micelles based on chemoenzymatic synthesis and self‐assembly of galactose‐functionalized ribavirin‐containing amphiphilic random copolymer
Authors: Li Xia , Wu Qi , Lu Min , Zhang Fu , Lin Xianfu
Published: March 2008

Hepatoma‐targeting micelles were successfully prepared by self‐assembly of galactose‐functionalized ribavirin‐containing amphiphilic random copolymer as novel drug delivery vehicles. The ribavirin‐containing random copolymer with galactose as the targeting ligand was facilely synthesized by combining enzymatic transesterification with radical polymerization and fully characterized by FTIR, NMR, and GPC. The formation of micelle‐type aggregates from the random copolymer was verified by UV–vis and fluorescence spectroscopy using pyrene as the guest molecule. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) experiments revealed that the micelles were well dispersed as spherical nanoparticles in water, whose hydrodynamic diameter was 217 ± 19 nm. Their biological recognition to fluorescein‐labeled peanut agglutinin investigated by confocal laser scanning microscopy (CLSM) proved the existence of hydrophilic galactose targeting moieties on the surface of micelles. Cell cytotoxicity tests and the inhibition experiment of galactose performed by MTT assay showed that the micelles had evident targeting function to hepG2 cells and the galactose moieties on the surface of micelles mediated cellar uptake of micelles. In vitro release studies indicated that ribavirin could be slowly released from the copolymer with pseudo zero‐order kinetics. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2734–2744, 2008
Thermodynamic of polymer mixtures: The LCT applied to the poly(styrene)/poly(vinyl methylether) system
Authors: Vicini Silvia , Princi Elisabetta , Pedemonte Enrico
Published: March 2008

In this article, the Lattice Cluster Theory developed by Freed and coworkers is applied to the poly(styrene)/poly(vinyl methylether) system by measuring the enthalpy and the volume variation associated with the mixing of the two homopolymers. It comes out that the chains architectures previously chosen for the two macromolecules based on the phase diagram and of the partition function developed by the theory correctly predicts the sign of both ΔHM and ΔVM. The foreseen trends as function of mixture composition fit the experimental data only for ΔVM; ΔHM is higher than predicted, asymmetrical and independent on the chain lengths of the components. The conclusion is that the theory needs some final touches in order to obtain a better agreement with experiments. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 791–797, 2008
Blast charts for explosive evaporation of superheated liquids
Authors: van den Berg A.C.
Published: March 2008

Explosive evaporation of superheated liquids is a hazard faced in many sectors of the process industries. The assumption that the explosive evaporation process is as fast as the inertia of the expanding mix of vapor and liquid in the surrounding air allows has been used as a safe and conservative starting point for the numerical computation of the blast. The result represents the maximum blast potential of an evaporating superheated liquid.

The modeling has been applied for the compilation of blast charts for some gaseous substances that are usually stored, transported, or handled in liquefied form. Because the blast charts have been directly computed from the gas dynamics of an explosive evaporation process, they enable a more realistic assessment of the blast potential of superheated liquids than the usual methods based on TNT‐equivalency. © 2008 American Institute of Chemical Engineers Process Saf Prog, 2008
Spectroscopic ellipsometry study of amorphous SrxBa1–xNb2O6 thin films obtained by pulsed laser deposition
Authors: Ion V. , Gâlcă A. C. , Scărisoreanu N. D. , Filipescu M. , Dinescu M.
Published: March 2008

Optical properties of amorphous Strontium Barium Niobate (a‐SBN) thin films are investigated using spectroscopic ellipsometry. Since the SBN can be applied to optoelectronic devices, the dispersion of refractive index is desirable. The films are obtained by Pulsed Laser Deposition (PLD) onto MgO and Si substrates by targeting a SBN:60 monocrystal. The dielectric function of a‐SBN is approximated using a single Tauc‐Lorentz oscillator model. Thicknesses of the films and of their rough layer are in agreement with SEM and AFM results. The dispersion of the refractive index is presented in the 1 –5 eV range. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Condensation and cleaning of an organometallic copper compound to/from porous low‐dielectric constant thin films in supercritical carbon dioxide
Authors: Kondoh E. , Ukai E. , Aruga S.
Published: March 2008

Porous low‐dielectric‐constant (low‐k) thin films are demanded as insulating material for high‐performance integrated circuits. One of the key technologies matching low‐k processing is the use of supercritical carbon dioxide (scCO2) fluids. ScCO2 has a nano‐penetration capability as well as solvent capability, which makes it a promising medium for the cleaning and modification of low‐k pores. However, few studies have been reported so‐far on in‐situ ellipsometric measurement within supercritical fluids. We have developed an in‐situ ellipsometry technique for use in scCO2. In this ar‐ticle, the sorption behaviour of an organometallic compound, Cu(dibm)2, on organosilica‐based low‐k thin films is reported as a model case of Cu contamination and the cleaning of low‐k pores. Reversible adsorption/desorption behaviour was observed when the amount of Cu(dibm)2 loaded was low, while less reversibility was observed when a larger amount of Cu(dibm)2 was used. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Suppression of backside reflections from transparent substrates
Authors: Synowicki R. A.
Published: March 2008

A variety of simple non‐destructive techniques were investigated to suppress backside reflections from transparent glass and plastic substrates. Different “glassy” materials such as translucent adhesive tape, white glue, grease, paint, and modelling clay were investigated and found to work well for substrate materials with refractive indices in the range of 1.35 to 1.60, including materials such as fused silica, float glass, display glass, microscope slides, plastic sheets, etc. These back‐surface suppression techniques are also useful in suppressing anisotropic effects from plastic substrates. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermal behaviour of chitosan and chitin thin films studied by spectroscopic ellipsometry
Authors: Montiel‐González Z. , Luna‐Bárcenas G. , Mendoza‐Galván A.
Published: March 2008

In‐situ spectroscopic ellipsometry was used to evaluate the temperature behaviour of chitin and chitosan thin films. For both biopolymers it was found that film thickness decreases with temperature. Two different linear rates were clearly identified by a characteristic temperature Tc, of 51 and 59 °C for chitin and chitosan, respectively. However, the refractive index for chitin decreases with temperature and a more complex behaviour was found for chitosan. The results of this work show that a more complex transformation than water desorption should be claimed to explain the observations. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of silicide stacks by combination of spectroscopic ellipsometry and reflectometry
Authors: Fursenko O. , Bolze D. , Costina I. , Zaumseil P. , Huelsmann T. , Niess J. , Lerch W.
Published: March 2008

In this work we show that by combining spectroscopic ellipsometry with reflectometry in the wavelength range from visual to deep ultraviolet the characterization of silicide (NiSi and CoSi2) stacks can be performed by determination of optical constants and thickness of all stack components. Especially, the diagnostic of the surface layer on silicide structures has been performed. By this way non‐destructive monitoring of silicidation process was improved.

Additional methods such as X‐ray photoelectron spectroscopy and atomic force microscopy were used to confirm the results. Different impacts of type and thickness of initial metal (Co or Ni), protective cap layer type (Ti or TiN), and rapid thermal process temperature on surface and silicide layers formation were found. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
UV‐induced in‐plane anisotropy in layers of mixture of the azo‐dyes SD‐1/SDA‐2 characterized by spectroscopic ellipsometry
Authors: Valyukh Iryna , Arwin Hans , Chigrinov Vladimir , Valyukh Sergiy
Published: March 2008

The optical properties of the azo‐dyes SD‐1/SDA‐2, which are used for photoaligning of liquid crystals (LCs), are investigated with Variable Angle Spectroscopic Ellipsometry (VASE). Films of mixture of SD‐1/SDA‐2 are deposited by spin coating on silicon wafers. The estimated thickness is approximately 10 nm. To achieve photo‐induced anisotropy, one of the samples is illuminated during 15 minutes with linearly polarized UV light followed by thermal stabilization during 1 hour at 150 °C. VASE measurements are performed in the wavelength range 200–1350 nm at several angles of incidence and at different sample orientations. Dielectric functions of azo‐dye films without/with polarized UV light illumination were modelled using an ensemble of Lorentz oscillators. The results confirm the diffusion model proposed recently for explanation of the formation of the photo‐induced order in azo‐dye films under the action of polarized light. Refractive indices, their wavelength dispersion and thicknesses of films of SD‐1/SDA‐2 are reported here. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Product decomposition of measured Mueller matrices from the FLC based NIR Mueller Matrix Ellipsometer
Authors: Stabo‐Eeg F. , Ladstein J. , Kildemo M.
Published: March 2008

This paper reports on the application of the first near‐infrared spectroscopic Mueller Matrix Ellipsometer (MME) based on Ferro‐electric Liquid Crystal retarders (FLC) and fixed waveplates. Operation of the instrument is demonstrated by transmission Mueller matrix measurements, and product decomposition of an imperfect dichroic polarizer and a depolarizing rough glass surface. The decomposition of the measured matrices is qualtitatively discussed in terms of retardance, diattenuation, depolarization, and azimuthal orientation. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fast near‐infra‐red spectroscopic Mueller matrix ellipsometer based on ferroelectric liquid crystal retarders
Authors: Ladstein J. , Stabo‐Eeg F. , Garcia‐Caurel E. , Kildemo M.
Published: March 2008

This paper reports on the design and construction of the first near‐infra‐red spectroscopic Mueller Matrix Ellipsometer (MME) based on Ferroelectric Liquid Crystal retarders (FLC) and fixed waveplates. The design was performed by assuming ideal optical polarizing components. In particular, the current FLC‐MME is optimised to operate in the near‐infra‐red (NIR) spectral range from 800 nm to 1800 nm. The FLC based Polarization State Generator (PSG) and Polarization State Analyzer (PSA) have been optimized by keeping the condition number of the PSG's modulation matrix and the PSA's analysis matrix close to an optimum over the spectral design range. The design is realized in a setup using the full Mueller matrix measurement formalism based on the Eigenvalue Calibration Method (ECM). The actual modulation matrix and analysis matrix are obtained from the ECM, and the condition numbers immediately indicates the quality of the design. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Combined effect of ultraviolet‐B radiation and cadmium contamination on nutrient uptake and photosynthetic pigments in Brassica campestris L. seedlings
Authors: Shukla U. C. , Murthy R. C. , Kakkar P.
Published: March 2008

Environmental and industrial pollution along with increase in ground level UV‐B radiation, because of stratospheric ozone depletion, present multiple stresses, which may affect crop photosynthesis and productivity. The present study was undertaken to see interactive effects of heavy metal contamination (Cd2+) and UV‐B exposure on essential nutrient (Ca2+, Mg2+, K+) uptake, biomass, and chlorophyll content in mustard (Brassica campestris L.) seedlings. Plants grown in 0.5, 1.0, 2.5, and 5.0 mg L−1 Cd2+ supplemented medium were exposed to UV‐B for 30 min (0.4 mW cm−2) per day. The interactive effect of two stresses measured after 5 and 10 days showed an overall decline in biomass. Under dual stress (5 mg Cd2+ L−1) significant (P < 0.001) decrease in chlorophyll a (43%), chlorophyll b (23%), and carotenoid (53%) was observed. Ca2+ uptake was reduced by 51% in roots under high doses of Cd2+ (5 mg L−1) and simultaneous exposure to 0.4 mW cm−2 UV‐B for 10 days. Mg2+ content was reduced by 48% and K+ by 62% under similar exposure conditions. Decline in nutrient uptake in Brassica campestris L. seedlings was observed both in root and shoot leaf in the initial growth period under controlled lab conditions. Cadmium ion (Cd2+) uptake was significantly enhanced by 33% (P < 0.001) in the presence of UV‐B. The findings are significant as multiple stress conditions prevalent in the environment play an important role during the early growth period, a period critical for crop yield. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2008.
Late Presentation of Intestinal Malrotation: An Argument for Elective Repair
Authors: Moldrem Amy W. , Papaconstantinou Harry , Broker Harshal , Megison Steve , Jeyarajah D. Rohan
Published: March 2008

Background

Midgut malrotation most commonly presents in young children. This diagnosis is not often entertained in the adolescent or adult with abdominal complaints. We reviewed our experience with this subset of malrotation patients.

Methods

A retrospective review of medical records from adolescent or adult patients identified with a diagnosis of anomaly of intestinal fixation or malrotation, who were treated within our health system between 1993 and 2004.

Results

A total of 33 patients were diagnosed with malrotation and treated with Ladd’s procedure. Acute abdominal pain was present in 50%, and chronic complaints were present in the other patients. Initial work‐up included computed tomography (CT) scan (28%), upper gastrointestinal (UGI) study (38%), and plain films (47%) Postoperative complications occurred more frequently in patients that were operated on emergently (60%) than in those that underwent elective surgery (22%; p = 0.04).

Conclusions

This large case series of intestinal malrotation in the nonpediatric age group suggests that Ladd’s procedure can be performed very safely. Moreover, the results suggest that patients with known malrotation should have Ladd’s procedure performed electively rather than urgently.
Folate and vitamin B12status in relation to cognitive impairment and anaemia in the setting of voluntary fortification in the UK
Authors: Clarke Robert , Sherliker Paul , Hin Harold , Molloy Anne M. , Nexo Ebba , Ueland Per M. , Emmens Kathleen , Scott John M. , Evans John Grimley
Published: March 2008

Concerns about risks for older people with vitamin B12deficiency have delayed the introduction of mandatory folic acid fortification in the UK. We examined the risks of anaemia and cognitive impairment in older people with low B12and high folate status in the setting of voluntary fortification in the UK. Data were obtained from two cross-sectional studies (n2403) conducted in Oxford city and Banbury in 1995 and 2003, respectively. Associations (OR and 95 % CI) of cognitive impairment and of anaemia with low B12status (holotranscobalamin < 45 pmol/l) with or without high folate status (defined either as serum folate >30 nmol/l or >60 nmol/l) were estimated after adjustment for age, sex, smoking and study. Mean serum folate levels increased from 15·8 (sd14·7) nmol/l in 1995 to 31·1 (sd26·2) nmol/l in 2003. Serum folate levels were greater than 30 nmol/l in 9 % and greater than 60 nmol/l in 5 %. The association of cognitive impairment with low B12status was unaffected by highv.low folate status (>30 nmol/l) (OR 1·50 (95 % CI 0·91, 2·46)v.1·45 (95 % CI 1·19, 1·76)), respectively. The associations of cognitive impairment with low B12status were also similar using the higher cut-off point of 60 nmol/l for folate status ((OR 2·46; 95 % CI 0·90, 6·71)v.(1·56; 95 % CI 1·30, 1·88)). There was no evidence of modification by high folate status of the associations of low B12with anaemia or cognitive impairment in the setting of voluntary fortification, but periodic surveys are needed to monitor fortification.
Grommet insertion using a branula
Authors: Raman R , Rahmat O
Published: March 2008

Objective:

To develop an easy method of performing myringotomy and grommet insertion, using minimal instruments.

Methods:

An ear speculum and a branula were used.

Results:

This method was found to be useful.

Conclusion:

An easy method of performing myringotomy and grommet insertion is proposed.
Management of temporal bone meningo-encephalocoele
Authors: Ramalingam K K , Ramalingam R , SreenivasaMurthy T M , Chandrakala G R
Published: March 2008

Meningo-encephalocoele of the temporal bone, also known as fungus cerebri, is a rare occurrence in clinical practice. We present a series of 13 patients with chronic otitis media who suffered brain herniation into the mastoid cavity. We also discuss the presentation and management of brain herniation with or without cerebrospinal fluid leak.

Study design:

Retrospective.

Methods:

Among 963 cases undergoing revision mastoid surgery, 13 patients suffered brain herniation. These cases were identified and analysed.

Results:

All 13 patients' initial diagnosis was chronic suppurative otitis media with cholesteatoma, and all had undergone previous mastoid surgery resulting in a defect in the tegmen and weakening of the dura mater. The revision procedures performed included 10 (76.9 per cent) modified radical mastoidectomies without ossicular chain reconstruction and one (7.6 per cent) modified radical mastoidectomy with ossicular chain reconstruction; two (15.3 per cent) patients required a blind sac closure. Brain herniation and/or cerebrospinal fluid leak were repaired by a transmastoid ± minicraniotomy procedure.

Conclusions:

Injury to the tegmen and dura should be avoided during surgery for chronic middle-ear disease. Cerebrospinal fluid leaks, if encountered, should be managed in the same surgical session. The transmastoid approach is helpful in repairing defects smaller than 1 cm in diameter, whereas the combined transmastoid-minicraniotomy approach provides good access when closing defects larger than 1 cm in diameter and also enables auto-calvarial grafting.
Strandings of striped dolphin Stenella coeruleoalba in Scottish waters (1992–2003) with notes on the diet of this species
Authors: Santos M.B. , Pierce G.J. , Learmonth J.A. , Reid R.J. , Sacau M. , Patterson I.A.P. , Ross H.M.
Published: March 2008

During 1992–2003, 52 striped dolphin strandings were recorded in Scotland (UK). Although strandings were recorded in every month of the year, highest numbers were found in January–March and August. Striped dolphins were stranded all around the Scottish coast, but the majority were recovered from the west coast. Necropsies were carried out on 33 of these animals: 29 had live-stranded and cause of death was not established for four animals. Stomach contents were analysed for 20 animals: whiting and Trisopterus were the main prey species in the diet (both by number and by reconstructed biomass). Females had a higher average number of Trisopterus in their stomachs than did males. Trisopterus eaten in winter were larger than Trisopterus eaten in summer and both Trisopterus and whiting eaten on the east coast were bigger than those eaten on the west coast. The reproductive status was determined for six females and six males during 2001–2003, with the majority being immature but the sample included one pregnant female and one sexually active mature male. We calculated the length–weight relationship for this species in Scottish waters. In addition, age data were collected from samples obtained during necropsies on six striped dolphins: the oldest dolphin sampled was around 14 y old but the majority were 2–7 y old. Although the numbers are low, the regular occurrence of stranded striped dolphins in recent years around Scotland, suggests that this warm water species may now be considered resident in Scottish waters.
Transmission and quantification of verocytotoxin-producingEscherichia coliO157 in dairy cattle and calves
Authors: SCHOUTEN J. M. , GRAAT E. A. M. , FRANKENA K. , VAN ZIJDERVELD F. , DE JONG M. C. M.
Published: March 2008

Data from a field study of 14 months duration in a naturally colonized dairy herd and data from an experiment with calves were used to quantify transmission of verocytotoxin-producingEscherichia coli(VTEC O157) in cattle. For the latter, two groups of 10 calves were randomly assigned and put out in one of two pastures. From each group, five animals were experimentally inoculated with 109c.f.u. O157 VTEC and, considered infectious, put back in their group. Each of the susceptible contact calves became positive within 6 days of being reunited. The estimate of the basic reproduction ratio (R0) in the experiment was 7·3 (95% CI 3·92–11·5), indicating that each infectious calf will infect seven other calves on average during an assumed infectious period of 28 days in a fully susceptible population. TheR0among dairy cows appeared to be about 10 times lower (0·70, 95% CI 0·48–1·04). After the transmission experiment, six contact-infected animals that were shedding continuously during the experiment were housed in a tie stall during winter. After 40 days, all six tested negative for O157 VTEC. In June, after a period of 34 weeks in which the heifers remained negative, they were put out in a clean and isolated pasture to observe whether they started shedding again. On each pasture that was infected with O157 VTEC during the transmission experiment the previous summer, newly purchased susceptible calves were placed. None of the heifers or calves started shedding during 14 weeks, indicating that both the heifers and the previously contaminated pasture did not function as reservoir of O157 VTEC.
FINNIS ON NATURE, REASON, GOD
Authors: Murphy Mark C.
Published: March 2008

It is often claimed that John Finnis's natural law theory is detachable from the ultimate theistic explanation that he offers in the final chapter of Natural Law and Natural Rights. My aim in this paper is to think through the question of the detachability of Finnis's theistic explanation of the natural law from the remainder of his natural law view, both in Natural Law and Natural Rights and beyond. I argue that Finnis's theistic explanation of the natural law as actually presented can be, without too much strain, treated as largely detachable in the way that his readers have by and large supposed it to be; indeed, Finnis's account as actually presented really amounts to no explanation of the natural law at all, theistic or otherwise, and that fact accounts in part for the ease with which Finnis's natural law view can be detached from theism of that final chapter. Nevertheless, the considerations raised in that chapter militate in favor of a much more thoroughgoing, largely nondetachable theistic account. And it is just such an account that we find Finnis affirming in the development of his views after Natural Law and Natural Rights.
Antigen-independent priming: a transitional response of bovine γδ T-cells to infection
Authors: Jutila Mark A. , Holderness Jeff , Graff Jill C. , Hedges Jodi F.
Published: March 2008

Analysis of global gene expression in immune cells has provided unique insights into immune system function and response to infection. Recently, we applied microarray and serial analysis of gene expression (SAGE) techniques to the study of γδ T-cell function in humans and cattle. The intent of this review is to summarize the knowledge gained since our original comprehensive studies of bovine γδ T-cell subsets. More recently, we have characterized the effects of mucosal infection or treatment with microbial products or mitogens on gene expression patterns in sorted γδ and αβ T-cells. These studies provided new insights into the function of bovine γδ T-cells and led to a model in which response to pathogen-associated molecular patterns (PAMPs) induces ‘priming’ of γδ T-cells, resulting in more robust responses to downstream cytokine and/or antigen signals. PAMP primed γδ T-cells are defined by up-regulation of a select number of cytokines, including MIP1α and MIP1β, and by antigens such as surface IL2 receptor α (IL-2Rα) and CD69, in the absence of a prototypic marker for an activated γδ T-cell, IFN-γ. Furthermore, PAMP primed γδ T-cells are more capable of proliferation in response to IL-2 or IL-15 in the absence of antigen. PAMPs such as endotoxin, peptidoglycan and β-glucan are effective γδ T-cell priming agents, but the most potent antigen-independent priming agonists defined to date are condensed oligomeric tannins produced by some plants.
Seasonal and latitudinal variation of noctilucent cloud altitudes
Authors: Lübken F.‐J. , Baumgarten G. , Fiedler J. , Gerding M. , Höffner J. , Berger U.
Published: March 2008

We present a summary of ∼1500 hours of lidar measurements of noctilucent cloud (NLC) altitudes at Kühlungsborn (54°N), ALOMAR (69°N), and Spitsbergen (78°N). Mean centroid altitudes (zc) are 82.75 km, 83.33 km, and 83.68 km, respectively. Standard deviations σ representing geophysical variability are ∼0.7–1.6 km. Errors of mean heights Δzc are much smaller (60–340 m). Several processes which are not yet fully understood influence zc. Therefore, σ is a better measure of uncertainties in zc compared to Δzc. The increase of NLC heights with latitude is very small (43 ± 65 m/deg) and statistically not significant. At ALOMAR zc varies with season by up to ∼1–1.5 km. NLC heights accumulate around climatological temperatures of 145 K at 69°N and 78°N (higher at 54°N). The LIMA model nicely reproduces observations and indicates that non‐variation of NLC heights at polar latitudes is caused by temperature uniformity: the 145 K isotherm varies in height by less than 250 m from the pole to 60°N.