bluuebunny/crossref_metadata_2025 huggingface dataset:
Preservice training in response to intervention: Learning by doing an interdisciplinary field experience
Authors: Hawkins Renee O. , Kroeger Stephen D. , Musti‐Rao Shobana , Barnett David W. , Ward Justine E.
Published: August 2008

Marking major changes in professional role performance, response to intervention (RTI) is now in the Individuals with Disabilities Education Act (IDEA, 2004) as a possible method to improve the identification of specific learning disabilities. Moreover, RTI and related concepts and initiatives have fundamentally influenced more general methods of prevention, instruction and intervention services, and decision making in schools. Although RTI will continue to evolve, core characteristics of RTI that form the basis of state initiatives are well founded in intervention and instructional research and practice. These core characteristics (i.e., data‐based decision making, evidence‐based intervention, teaming, and problem solving) represent skills immediately needed by professionals‐in‐training. This article reports collaboration between school psychology and special education faculty in designing and implementing an integrative field experience in RTI. Training, student, and program outcomes are used summatively for accountability. © 2008 Wiley Periodicals, Inc.
The influence of student perceptions of parenting and coping on achievement and classroom behavior among African American children
Authors: Gaylord‐Harden Noni K.
Published: August 2008

The present study examined children's coping strategies as mediators and moderators of the association between parenting factors and outcomes in 235 African American children (mean age = 10.37 years). Information about parenting and child coping strategies was obtained by child self‐report. School adjustment was assessed by standardized achievement scores and by teacher ratings of behavior. Structural equation modeling indicated that positive parenting was related to higher achievement and lower behavior problems. Contrary to the hypotheses, coping strategies did not mediate or moderate this association. The results are discussed in terms of how factors at the family and child level may influence child behavior and academic performance in the classroom. © 2008 Wiley Periodicals, Inc.
Psychological functioning in persons considering genetic counseling and testing for Li–Fraumeni syndrome
Authors: Peterson Susan K. , Pentz Rebecca D. , Marani Salma K. , Ward Patricia A. , Blanco Amie M. , LaRue Denise , Vogel Kristen , Solomon Tamara , Strong Louise C.
Published: August 2008

Objective: Li–Fraumeni syndrome (LFS) confers an increased risk of multiple types of cancer in both children and adults. Clinical genetic testing for deleterious germline p53 gene mutations can identify most LFS‐affected families. We evaluated factors associated with cancer‐specific distress and perceived self‐efficacy in coping with a positive genetic test result among persons at risk of having deleterious p53 mutations.

Methods: One hundred thirty‐five persons from 15 LFS‐affected families were invited to take part in a study that offered p53 genetic counseling and testing and to complete psychosocial measures.

Results: Participants (n=92) were more likely to be younger and female than nonparticipants (n=43). In multivariate analyses, greater cancer‐specific distress was associated with having a lower quality of life, a higher perceived risk of having a p53 mutation, no personal history of cancer and a greater number of first degree relatives (FDRs) affected with cancer. Lower perceived self‐efficacy in coping with a positive test result was associated with greater cancer worry, higher decisional conflict about p53 testing and having no personal history of cancer.

Conclusions: Individual perceptions about cancer risk and p53 genetic testing, as well as personal experience with FDRs' cancer diagnoses and deaths, should be addressed during the counseling and testing process for LFS‐affected families. Copyright © 2008 John Wiley & Sons, Ltd.
Validation of DSD Relations for RDX‐TNT‐Based Cast Explosives for Lower Diameters and Dn–κ Surface Equation
Authors: Rofi Shakeel Abbas , Fenglei Huang
Published: August 2008

In this paper, we extended our work on RDX and TNT‐based explosives to lower diameter to validate detonation shock dynamics (DSD) first‐order relationships between normal detonation velocity Dn and detonation wave curvature κ. At 25 mm diameter, we observed that Dn–κ relationship approximates, although not perfectly, the relation for 50 mm diameter. Thus to an approximation, the first order DSD theory is independent of geometry. On that basis, a general equation has been proposed, which can predict Dn–κ for RDX/TNT cast explosives in the mixing ratios 60 : 40–40 : 60.
Production of Exploding Materials for Electro Explosive Devices
Authors: Orbovic Nikola , Luco Ana Cofré , Bozovic Milomir
Published: August 2008

The production of some explosive materials for use in the manufacture of electro explosive devices has been investigated. This work concerns the production of lead salts of some polynitro derivatives of hydroxybenzene (phenol), 1,3‐dihydroxybenzene (resorcinol), and carboxybenzene (benzoic acid), suitable for making fusehead dipping suspensions. During our research, we have discovered that polynitro derivatives of phenol, resorcinol, and benzoic acid react directly with lead oxide in semi‐aprotic solvents such as ethanol or methanol, without the need to convert them to soluble salts. After filtering, washing, and drying (only partially) the products can be used, in wet state for electro explosive device manufacture, without any pretreatment (total drying, screening, or ball grinding). The reactions depend on the acidity of the polynitro derivatives. The effect of different solvents, reaction temperature, procedure, and others, on the product yields and quality has been investigated. The acidity of the polynitro derivatives is the driving force for the reaction. The type of solvent (semi‐aprotic, moderate proton attraction) allows that reactions take place slowly and with uniform particle sizes. The reaction mechanism is discussed. Some of the products obtained in wet state, were used for dipping mixtures and fusehead production. The obtained dipping mixtures have very good stability regarding sedimentation. Fuseheads made with these dipping mixtures have the expected performance.
Malayamycin, a new streptomycete antifungal compound, specifically inhibits sporulation of Stagonospora nodorum (Berk) Castell and Germano, the cause of wheat glume blotch disease
Authors: Li Wenfeng , Csukai Michael , Corran Andrew , Crowley Patrick , Solomon Peter S , Oliver Richard P
Published: August 2008

BACKGROUND: Malayamycin is a novel perhydrofuropyran C‐nucleoside isolated from Streptomyces malaysiensis that shows promising antifungal activity, fully controlling a range of diseases when applied to plants at 100 µg mL−1. The goal of this study was to determine the mode of action.

RESULTS: Malayamycin exhibited in vitro antifungal activity against Stagonospora nodorum (Berk) Castell & Germano, the cause of stagonospora nodorum blotch of wheat. Growth in liquid minimum medium was merely delayed at 50 µg mL−1, but sporulation was suppressed by more than 50% by 10 µg mL−1 of malayamycin. When applied to wheat seedlings 36 h prior to infection, 10 µg mL−1 of malayamycin reduced lesion size and significantly reduced pycnidiation to only 5% of the non‐treated level. A transcription factor gene, Mrg1 (malayamycin response gene) whose expression was upregulated by application of malayamycin, was identified. Both Mrg1 knockout and overexpression strains were created. These strains were fully pathogenic, suggesting that the expression of Mrg1 did not affect pathogenicity. Interestingly, a strain that expressed Mrg1 50 times more than wild type showed a significant reduction in sporulation. However, all the tested knockout and overexpression strains retained sensitivity to malayamycin.

CONCLUSIONS: Malayamycin is a new type of antifungal compound that acts primarily by inhibiting sporulation. Although Mrg1 may be involved in the sporulation process, it is not the major contributor for sporulation inhibition caused by malayamycin treatment. Copyright © 2008 Society of Chemical Industry
Magnetic‐field dependence of electrothermal conductivity in YBCO
Authors: Mariño A. , Uribe R.
Published: August 2008

Experimental measurements of the electrothermal conductivity (P) near Tc, as a function of external magnetic field were carried out in undoped YBCO (123) superconducting samples. The electrothermal conductivity which relates electrical and thermal currents, depends on the applied magnetic field in high Tc materials, contrary to conventional low Tc superconductors where P is nearly independent of the magnetic field. The experimental P (B, T) data determined from resistivity and thermopower measurements were analyzed in terms of theoretical models and showed a behavior consistent with an order‐parameter symmetry (OPS) of d‐wave type. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Progress in dye‐sensitized solid state solar cells
Authors: Sirimanne P. M. , Perera V. P. S.
Published: August 2008

Recently, dye sensitized solid‐state solar cells with the configuration of n‐semiconductor | sensitizer | hole‐conductor (NDP) have been demonstrated. The maximum power conversion efficiency of this type of solar cells reaches only one third compared to that of dye sensitized photo‐electrochemical cells. The properties of different types of solid‐state dye‐sensitized solar cells are discussed with the aim to understand the mechanisms of operation of these devices. Here we present an overview and the current state of NDP type solar cells based on copper iodide (or copper thiocyanate) as a hole‐conductor. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Origin of the broad lifetime distribution of localized excitons in InGaN/GaN quantum dots
Authors: Winkelnkemper M. , Dworzak M. , Bartel T. P. , Strittmatter A. , Hoffmann A. , Bimberg D.
Published: August 2008

We derive an energy‐dependent decay‐time distribution function from the multi‐exponential decay of the ensemble photoluminescence (PL) of Inx Ga1–x N/GaN quantum dots (QDs), which agrees well with recently published single‐QD time‐resolved PL measurements. Using eight‐band k · p modelling, we show that the built‐in piezo‐ and pyroelectric fields within the QDs cause a sensitive dependence of the radiative lifetimes on the exact QD geometry and composition. Moreover, the radiative lifetimes also depend heavily on the composition of the direct surrounding of the QDs. A broad lifetime distribution occurs even for moderate variations of the QD structure. Thus, for unscreened fields a multi‐exponential decay of the ensemble PL is generally expected in this material system. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural, electronic and optical properties of spinel MgAl2O4 oxide
Authors: Hosseini S. M.
Published: August 2008

The structure, band structure, total density of states, dielectric function, reflectivity, refractive index and loss function have been calculated for spinel MgAl2O4 oxide using density functional theory. The full‐potential linearized augmented plane wave method was used with the generalized gradient approximation. Calculations of the optical spectra have been performed for the energy range 0–40 eV. It is shown that the material is transparent at visible wavelengths and the dispersion curve of the refractive index is fairly flat in the long‐wavelength region and rises rapidly towards shorter wavelengths. The refractive index is 1.774 at 800 nm near the visible region. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Impurity effects on Fe‐ or MgO‐doped LiNbO3 crystals studied by 7Li and 93Nb NMR relaxation
Authors: Yeom Tae Ho , Lim Ae Ran , Noiret I.
Published: August 2008

The spin–lattice and spin–spin relaxation times of 7Li and 93Nb nuclei were investigated as a function of the concentration of Fe or MgO species in LiNbO3 crystals using pulse NMR spectrometry. The spin–lattice relaxation times T1 of both nuclei were found to decrease as the number of Fe impurities increased in Fe‐doped LiNbO3 single crystals, because of paramagnetic‐impurity effects. On the other hand, the T1 values of the 7Li and 93Nb nuclei in LiNbO3:MgO crystals remained nearly constant with increasing MgO concentration. The T1 of 7Li was found to be longer than that of 93Nb for both Fe‐ or MgO‐doped single crystals. The spin–spin relaxation times T2 of the 7Li and 93Nb nuclei remained nearly constant with increasing concentration of Fe or MgO. From our results, we can conclude that T1 depends on the concentration of Fe impurities but is independent of the concentration of Mg impurities. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Carrier density and effective mass calculations in carbon nanotubes
Authors: Marulanda Jose M. , Srivastava Ashok
Published: August 2008

In this work, the intrinsic carrier concentration and doping effects have been investigated for different carbon nanotubes. Electronic structure and the density of states functions have been utilized to derive analytical equations for the carrier concentration under high and low doping concentrations. The temperature dependence has also been investigated. The results show how varying diameters and wrapping angles of carbon nanotubes change their concentration profile. The implications of these results allow us to use the same material (carbon nanotube) for a wide range of applications only by varying the chiral vector (n,m). The calculations performed in this work set an upper limit for a wide range of applications including carbon nanotube interconnects and carbon nanotube field effect transistors. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrodeposition of α‐ and β‐cobalt hydroxide thin films via dilute nitrate solution reduction
Authors: Brownson Jeffrey R. S. , Lévy‐Clément Claude
Published: August 2008

α‐ and β‐cobalt hydroxyde thin films were synthesized by cathodic electrodeposition on transparent conductive oxide (TCO) substrates, at 60 °C and 95 °C, respectively, using a very low concentration of Co(NO3)2 and an alkali nitrate supporting electrolyte. Localized cathodic electrochemical generation of hydroxyl species via the reduction of nitrate precursors led to the formation of well crystallized nanostructured films. Scanning Electron Microscopy and X‐ray diffraction confirmed the films were composed of vertically oriented nanoparticle platelets with the c‐axis parallel to the substrate surface, and free of turbostratic disorder. UV/Vis spectra and thermal gravimetric analyses (TGA) indicated variation between the cobalt structures. Films deposited at 60 °C yielded a hydrotalcite‐like compound namely an “hydroxyl‐deficient” [Co(OH)2–x (H2O)x ]x + with NO3– intercalated anion along with water molecules in the interlayer region. Those deposited at 95 °C yielded the brucite β‐Co(OH)2. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Highly active photocatalyst Bix Tiy Vx O4x +2y (x ≈ y) for oxygen evolution under visible‐light illumination
Authors: Liu Haimei , Imanishi Akihito , Nakamura Ryuhei , Nakato Yoshihiro
Published: August 2008

A coupled TiO2‐BiVO4 system, Bix Tiy Vx O4x +2y (x ≈ y), with modified TiO2 and BiVO4 crystals through their interaction, was prepared in the form of powder by solid‐state reaction under the concept of combining properties of active photocatalysts. Experiments of photocatalytic oxygen evolution from an aqueous powder suspension under visible‐light irradiation (λ ≥ 420 nm) have shown that Bix Tiy Vx O4x +2y (x ≈ y) exhibits activity much higher than that of BiVO4, which is known as one of the most active visible‐light‐responsive photocatalysts, indicating the effectiveness of the interaction and the modification of TiO2 and BiVO4. XRD experiments showed that Bix Tiy Vx O4x +2y (x ≈ y) was composed of BiVO4 and TiO2 crystals slightly modified probably by partial exchange of V5+ and Ti4+ ions. Photocurrent vs. wavelength for a particulate Bix Tiy Vx O4x +2y (x ≈ y) film electrode demonstrated several components, in agreement with the conclusion that Bix Tiy Vx O4x +2y (x ≈ y) consisted of modified BiVO4 and TiO2 crystals. A possible band model was tentatively proposed to explain observed characteristics such as photocurrent density (j) vs. potential (U), j vs. illumination wavelength (λ), the U dependence of j vs. λ, and the effect of the addition of a reductant such as I−, MeOH, SCN− and Br– on j vs. U and j vs. λ. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Niobium‐doped TiO2 films as window layer for chalcopyrite solar cells
Authors: Neumann Bernhard , Bierau Frauke , Johnson Benjamin , Kaufmann Christian Alexander , Ellmer Klaus , Tributsch Helmut
Published: August 2008

Smooth and semitransparent Nbx Ti1–x Oy (x = 0.03, y = 1.84–1.91) films have been prepared by reactive magnetron sputtering at temperatures below 420 K. Structural investigations by RAMAN‐spectroscopy together with resistivity‐ and temperature‐dependent Hall‐measurements were used in order to analyze the film structure and the nature of the charge transport in this material. These films can be used as a window layer (TCO) for thin film solar cells. Cu(In,Ga)Se2 solar cells equipped with the new window layer keep their functionality which excludes first, the presence of strong energetic barriers and second, a strong interfacial recombination. The development of TiO2‐based window layers is expected to make thin film solar cells less sensitive against corrosion after contact with humidity. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Enzyme–semiconductor interactions: Routes from fundamental aspects to photoactive devices
Authors: Lewerenz H. J.
Published: August 2008

Scanning tunnelling microscopy (STM) experiments at protein–semiconductor systems are analyzed using concepts from applied semiconductor physics such as Fermi level pinning and MIS (metal–insulator–semiconductor) junction electronics. Routes for immobilization of enzymes (proteins) on nanostructured surfaces of MoTe2 and Si are outlined using so‐called DLVO and non‐DLVO interaction forces. An overview of the catalytic activity of the imaged enzymes, reverse transcriptases of the retroviruses HIV 1 and AMV (avian myeloblastosis virus), is given including their tertiary structural properties which is revealed also in the STM and tapping mode AFM images. For the interpretation of STM images, a resonant charge transfer mechanism is invoked, based on the potential dependence of the image contrast and the energy band structure of MoTe2 near the valence band maximum. First analyses of the charge transport from the semiconductor to the STM tip at negative bias of MoTe2 suggest that the observed uninhibited conductivity in the constant current experiments results from solvation‐assisted release of electrons from traps that exist along the polypeptide chains and that charge transport occurs at the circumference of the enzymes where biological water is present. Therefore, charge injection into catalytically active enzymes such as hydrogenase or water oxidase of Photosystem I and II with subsequent charge transport to the active sites appears difficult to realize. Possibilities of radiation‐less long‐distance energy transfer based on the Förster mechanism, its multichromic extension and on Dexter exciton hopping are considered for catalytically active hybrid inorganic/organic absorber–enzyme structures. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preparation routes based on magnetron sputtering for tungsten disulfide (WS2) films for thin‐film solar cells
Authors: Ellmer K.
Published: August 2008

The semiconductor tungsten disulfide (WS2) exhibits van der Waals bonding, crystallizes in a layer‐type structure and is of interest as an absorber layer for thin‐film solar cells. In this review article different preparation routes for WS2 thin films, based on magnetron sputtering, are reviewed. Films prepared by direct magnetron sputtering, though exhibiting quite a good structural quality, are not or only poorly photoactive. This can be attributed to the generation of recombination centers, especially sulfur vacancies, during the ion bombardment of the films, due to the low defect‐formation energy of tungsten disulfide, an intrinsic property of transition metal dichalcogenides. A promising preparation route, which leads to photoactive WS2 films, is a two‐step process, where, in a first step, a sulfur‐rich, X‐ray amorphous tungsten sulfide is deposited at low substrate temperatures onto a thin metal film (Ni, Co). This film sandwich is after wards annealed in an ampoule in a sulfur atmosphere or in flowing gas with a sufficient H2S partial pressure. From in‐situ transmission electron microscopy and energy‐dispersive X‐ray diffraction, it was found that the WS2 film crystallization with a pronounced (001) texture is closely related to the formation of the liquid (eutectic) metal–sulfur phase. Based on these in‐situ investigations the growth of the 2‐dimensional WS2 nanosheets from an amorphous WS3+x precursor can be described as an amorphous solid‐liquid‐crystalline solid process (SLS), somewhat similar to the well‐known vapor‐liquid‐solid (VLS) process for the growth of whiskers or nanorods and nanotubes. Research opportunities, to overcome current limitations for a broad use of WS2 (and MoS2) as thin‐film solar cell absorbers are given. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the homogeneity region, growth modes and optoelectronic properties of chalcopyrite‐type CuInS2
Authors: Fiechter Sebastian , Tomm Yvonne , Kanis Michael , Scheer Roland , Kautek Wolfgang
Published: August 2008

Studying the pseudo‐binary phase diagrams of Cu2S–In2S3 and CuS–InS in the ternary system Cu–In–S showed that the CuInS2 compound semiconductor exhibits a melting point at T = 1093(±3) °C and a homogeneity region at room temperature ranging from 2 mol% in In2S3 to 1.5 mol% in the CuS direction. This material, which crystallizes in the chalcopyrite‐type structure, occurs in nature as the mineral roquésite. Investigating the influence of inert gas pressure on the crystallization of a stoichiometric melt, a disproportionation of the crystallized material into a Cu2S‐rich bulk material of composition Cu1.06In0.98S2 epitaxially intergrown with ∼1.5 µm thick lamellae of the thiospinel phase CuIn5S8 was observed. Structure and composition of the bulk material were characterized by applying scanning Auger microscopy (SAM) and scanning electron microscopy (SEM) as well as differential thermal analysis (DTA) and X‐ray diffractometry (XRD). In photoluminescence measurements (PL), Cu‐rich bulk material is distinguished by sharp emission lines representing excitons close to the band to band transition at 1.55 eV and a broadband emission in the range from 1.3 eV to 1.45 eV. Exciton peaks of highest intensity were found at a Cu:In ratio = 1.0524. Investigating the spectral response of thin film chalcopyrite solar cells, a significant change of the optical gap from 1.45 eV for a “Cu‐rich” to 1.37 eV for an “In‐rich” absorber layer was observed. The results show that the homogeneity region of the material can be varied in the percentage range. A shift of the optical band gap can be influenced by stoichiometry (at% sulphur: at% metal) and the crystallization conditions of the adamantine‐type structure. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of different doses of Manuka honey in experimentally induced inflammatory bowel disease in rats
Authors: Prakash A. , Medhi B. , Avti P. K. , Saikia U. N. , Pandhi P. , Khanduja K. L.
Published: August 2008

To evaluate the effect of different doses of Manuka honey in experimentally induced inflammatory bowel disease in rats. Adult Wistar rats of either sex were used (n = 30). Colitis was induced by a single intracolonic administration of TNBS dissolved in 35% ethanol. The rats (n = 30) were divided into five groups (n = 6) and were treated with vehicle (ethanol), TNBS, Manuka honey (5 g/kg, p.o.), Manuka honey (10 g/kg, p.o.) or sulfasalazine (360 mg/kg, p.o.) body weight for 14 days. After completion of treatment, the animals were killed and the following parameters were assessed: morphological score, histological score and different antioxidant parameters.

Manuka honey at different doses provided protection against TNBS‐induced colonic damage. There was significant protection with Manuka honey 5 g/kg as well as with 10 g/kg body weight compared with the control (p < 0.001). All the treated groups showed reduced colonic inflammation and all the biochemical parameters were significantly reduced compared with the control in the Manuka honey treated groups (p < 0.001). Manuka honey at different doses restored lipid peroxidation as well as improved antioxidant parameters. Morphological and histological scores were significantly reduced in the low dose Manuka honey treated group (p < 0.001). In the inflammatory model of colitis, oral administration of Manuka honey 5 g/kg and Manuka honey 10 g/kg body weight significantly reduced the colonic inflammation. The present study indicates that Manuka honey is efficacious in the TNBS‐induced rat colitis model, but these results require further confirmation in human studies. Copyright © 2008 John Wiley & Sons, Ltd.
Effect of Tilia × viridis flower extract on the proliferation of a lymphoma cell line and on normal murine lymphocytes: contribution of monoterpenes, especially limonene
Authors: Manuele Maria Gabriela , Ferraro Graciela , Anesini Claudia
Published: August 2008

Tilia species are widely used in Europe as medicinal plants. The selective antiproliferative activity of a Tilia cordata flower dichloromethane extract (DME) on a lymphoma cell line has been reported previously and in order to extend this to other unstudied Tilia species, the effect of Tilia × viridis DME on the proliferation of tumor and normal murine lymphocytes was investigated. The bioguided fractionation of DME yielded a fraction rich in limonene (L), α‐pinene and β‐pinene, which presented a selective antiproliferative action on tumor lymphocytes (EC50 on tumor cells: 3.8 ± 0.2 µg/mL; EC50 on normal cells: 205 ± 1.8 µg/mL). While all monoterpenes exhibited this activity, limonene proved to be the most active (EC50 on tumor cells: 35 ± 2.0 µg/mL; EC50 on normal cells: 72 ± 5.0 µg/mL) also exerting a stimulatory effect on non‐mitogen stimulated lymphocytes proliferation (% of stimulation respect to control) (mean ± SEM): L 10 µg/mL: 25 ± 1.0%; 20 µg/mL: 38.5 ± 2.5%; L 40 µg/mL: 41 ± 0.9%; L 60 µg/mL: 58.5 ± 3%. T. × viridis may thus constitute a potential source of monoterpenes with immunomodulatory activity. Copyright © 2008 John Wiley & Sons, Ltd.
The effects of Alcea rosea L., Malva sylvestris L. and Salvia libanotica L. water extracts on the production of Anti‐egg albumin antibodies, interleukin‐4, gamma interferon and interleukin‐12 in BALB/c mice
Authors: Ghaoui Walid Bou Jaber El , Ghanem Elsa Bou , Chedid Lara Abou , Abdelnoor Alexander M.
Published: August 2008

Polysaccharides obtained from certain plants have been reported to have immunomodulatory properties. As a consequence of these reports the aim of this study was to investigate some immunomodulatory properties of water extracts of Alcea rosea L. (ARE), Malva sylvestris L. (MSE) and Salvia libanotica L. (SLE).

Groups of egg albumin (EA)‐immunized and ‐non‐immunized Balb/c mice were treated with the carbohydrate‐rich water extracts. Mice from each group were bled and their spleens removed at 3, 6 and 10 days post‐immunization/treatment. Anti‐egg albumin antibody levels in the processed sera were determined by an enzyme linked immunosorbent assay (ELISA). RNA was extracted from spleen cells and interleukin‐4 (IL‐4), interleukin‐12 (IL‐12) and γ‐interferon transcripts were determined by the reverse transcription polymerase chain reaction (RT‐PCR).

ARE appeared to boost the antibody response to EA, but had no effect on IL‐4 and γ‐interferon gene transcription. MSE and SLE appeared to have no effect on anti‐EA antibody production, but enhanced IL‐12 and γ‐interferon gene transcription. MSE appeared to switch off, and SLE had no effect on, IL‐4 transcription.

In conclusion, it appears that ARE is a B‐lymphocyte polyclonal activator, and MSE and SLE are macrophage and T helper‐1 (Th‐1) activators. Copyright © 2008 John Wiley & Sons, Ltd.
Buddleja officinalis inhibits high glucose‐induced matrix metalloproteinase activity in human umbilical vein endothelial cells
Authors: Lee Yun Jung , Kang Dae Gill , Kim Jin Sook , Lee Ho Sub
Published: August 2008

The aim of the present investigation was to investigate whether an aqueous extract of Buddleja officinalis (ABO), a traditional Korean herbal medicine, suppresses the endothelial extracellular matrix degradation under high glucose condition. The incubation with high concentration of glucose (25 mM) increased significantly matrix metalloproteinase (MMP)‐2/‐9 expressions and activities in primary cultured human umbilical vein endothelial cells (HUVEC). Pretreatment with ABO decreased high glucose‐induced increase of MMP‐2/‐9 activities in a dose‐dependent manner. Real time qRT‐PCR revealed that high glucose‐induced MMP‐2/‐9 mRNA expression levels were attenuated by pretreatment with ABO. High glucose‐induced MCP‐1 and IL‐8 mRNA expression levels also decreased by ABO. ABO decreased high glucose‐induced hydrogen peroxide production, oxidative stress marker. These results provide new insights into the pathophysiological mechanisms for anti‐inflammatory properties of ABO in vascular diseases associated with diabetes mellitus. Copyright © 2008 John Wiley & Sons, Ltd.
Echinacea purpureaand P‐glycoprotein drug transport in Caco‐2 cells
Authors: Hansen Torstein Schrøder , Nilsen Odd Georg
Published: August 2008

Echinacea is widely used as a medical herbal product, but its interaction potential with the drug efflux transporter P‐glycoprotein (P‐gp) has not yet been evaluated. The interaction potential ofEchinacea purpureatowards P‐gp mediated drug transport was studied in human intestinal Caco‐2 cells. Digoxin (30 nm) was used as a substrate and verapamil as a control inhibitor. Ethanol, 0.8%, needed for herbal extraction and compatibility with the commercial products, inhibited the net digoxin flux by 18%.E. purpureainfluenced to a higher degree the B–A transport of digoxin than the A–B transport. A minor increase in net digoxin flux was observed at low concentrations ofE. purpurea, an effect anticipated to be allosteric in nature. At higher concentrations, from 0.4 to 6.36 mg dry weight/mL, a statistically significant linear dose‐related decrease was observed in the net digoxin flux, indicating a dose dependentE. purpureainhibition of P‐gp. BothVmaxandKmof the net digoxin flux, calculated to 23.7 nmol/cm2/h and 385 µm, respectively, decreased in the presence ofE. purpureain an uncompetitive fashion. Although the effects ofEchinacea purpureaon systemic P‐gp mediated drug transport are probably limited, an influence on drug bioavailability can not be excluded. Copyright © 2008 John Wiley & Sons, Ltd.
Advances in simulating atmospheric variability with the ECMWF model: From synoptic to decadal time‐scales
Authors: Bechtold Peter , Köhler Martin , Jung Thomas , Doblas‐Reyes Francisco , Leutbecher Martin , Rodwell Mark J. , Vitart Frederic , Balsamo Gianpaolo
Published: August 2008

Advances in simulating atmospheric variability with the ECMWF model are presented that stem from revisions of the convection and diffusion parametrizations. The revisions concern in particular the introduction of a variable convective adjustment time‐scale, a convective entrainment rate proportional to the environmental relative humidity, as well as free tropospheric diffusion coefficients for heat and momentum based on Monin–Obukhov functional dependencies.

The forecasting system is evaluated against analyses and observations using high‐resolution medium‐range deterministic and ensemble forecasts, monthly and seasonal integrations, and decadal integrations with coupled atmosphere‐ocean models. The results show a significantly higher and more realistic level of model activity in terms of the amplitude of tropical and extratropical mesoscale, synoptic and planetary perturbations. Importantly, with the higher variability and reduced bias not only the probabilistic scores are improved, but also the midlatitude deterministic scores in the short and medium ranges. Furthermore, for the first time the model is able to represent a realistic spectrum of convectively coupled equatorial Kelvin and Rossby waves, and maintains a realistic amplitude of the Madden–Julian oscillation (MJO) during monthly forecasts. However, the propagation speed of the MJO is slower than observed. The higher tropical tropospheric wave activity also results in better stratospheric temperatures and winds through the deposition of momentum.

The partitioning between convective and resolved precipitation is unaffected by the model changes with roughly 62% of the total global precipitation being of the convective type. Finally, the changes in convection and diffusion parametrizations resulted in a larger spread of the ensemble forecasts, which allowed the amplitude of the initial perturbations in the ensemble prediction system to decrease by 30%. Copyright © 2008 Royal Meteorological Society
Average run length when monitoring capability indices using EWMA
Authors: Castagliola P. , Vännman K.
Published: August 2008

In order to monitor unstable but capable processes Castagliola and Vännman have recently suggested a procedure based on an EWMA approach, called EWMA capability chart, for monitoring Vännman's Cp(u,v)‐family of capability indices and showed how their proposed approach efficiently monitors capable processes by detecting a decrease or increase in the capability level. The goal of this paper is to investigate the efficiency of this capability chart in terms of ARL. The procedure used for computing this ARL is presented and simple guidelines for obtaining approximations to the optimal EWMA parameters are proposed. Copyright © 2008 John Wiley & Sons, Ltd.
A sequential constant‐stress accelerated life testing scheme and its Bayesian inference
Authors: Liu Xiao , Tang Loon‐Ching
Published: August 2008

In the analysis of accelerated life testing (ALT) data, some stress‐life model is typically used to relate results obtained at stressed conditions to those at use condition. For example, the Arrhenius model has been widely used for accelerated testing involving high temperature. Motivated by the fact that some prior knowledge of particular model parameters is usually available, this paper proposes a sequential constant‐stress ALT scheme and its Bayesian inference. Under this scheme, test at the highest stress is firstly conducted to quickly generate failures. Then, using the proposed Bayesian inference method, information obtained at the highest stress is used to construct prior distributions for data analysis at lower stress levels. In this paper, two frameworks of the Bayesian inference method are presented, namely, the all‐at‐one prior distribution construction and the full sequential prior distribution construction. Assuming Weibull failure times, we (1) derive the closed‐form expression for estimating the smallest extreme value location parameter at each stress level, (2) compare the performance of the proposed Bayesian inference with that of MLE by simulations, and (3) assess the risk of including empirical engineering knowledge into ALT data analysis under the proposed framework. Step‐by‐step illustrations of both frameworks are presented using a real‐life ALT data set. Copyright © 2008 John Wiley & Sons, Ltd.
A3M: an agent architecture for automated manufacturing
Authors: Di Stefano Antonella , Santoro Corrado
Published: August 2008

This paper proposes a software architecture based onmobile agentsfor distributed process control applications. A set of agents is employed to handle, in a single manufacturing cell, automatic assignment of control tasks to controllers, monitoring of cell functionalities and dynamic cell reconfiguration. The agents operate in a two‐layered structure: at the highest level, theplanning agentsanalyse the inputs of the system designer and automatically create thefield agents, which operate at the lowest level and embed the control tasks to be executed. Field agents, which are mobile, are able to reach autonomously the controllers of the cell, in order to perform the control activity there. Exploiting the mobility enables a field agent to change its running device when the variation of the design parameters or a system fault requires a new task distribution. Aload‐balancingalgorithm is introduced, with the objective of assigning each field agent to a controller of the manufacturing cell in order to fairly distribute the computation load. The algorithm uses abranch‐and‐boundtechnique to explore all possible solutions and applies two heuristics to throw away non‐feasible solutions and select the best branch to analyse. The algorithm is designed to run on‐line in order to allow a fast task redistribution when a fault condition occurs in the process control environment. Copyright © 2008 John Wiley & Sons, Ltd.
Prenatal detection of trisomy 21 by second‐trimester ultrasound examination and maternal age in a non‐selected population of 49 314 births in Norway
Authors: Offerdal K. , Blaas H.‐G. K. , Eik‐Nes S. H.
Published: August 2008

Objectives

To assess the contribution of the second‐trimester routine ultrasound examination and maternal age (≥ 38 years) to the prenatal detection of trisomy 21 in a large non‐selected population in which no other screening methods were carried out.

Methods

A prospective follow‐up study was carried out in a non‐selected Norwegian population from 1987 to 2004, including a total of 49 314 births. Data from all cases of trisomy 21, detected prenatally by karyotyping following amniocentesis performed for abnormal ultrasound findings or because of maternal age ≥ 38 years, or postnatally after delivery, were registered. The study period was divided into three 6‐year periods.

Results

Eighty‐eight cases of trisomy 21 were registered. The prenatal detection rate was 43% (38/88). No significant change in the detection rate was observed over the 18 years. Fourteen percent (12/88) of cases were detected as a result of advanced maternal age and 30% (26/88) by prenatal ultrasound examination. Of all women with a trisomy 21 fetus, 72% (63/88) were under 38 years of age. The percentage of women ≥ 38 years opting for karyotyping during the three time periods decreased significantly from 51% to 50% and 36%, respectively. The termination rate of trisomy 21 fetuses was 84%, with no significant change over time.

Conclusions

Our data can be considered as a reference standard for population screening for trisomy 21 based solely on maternal age and second‐trimester ultrasound imaging. The prenatal detection rate of trisomy 21 cases was poor and remained unchanged throughout the 18‐year study period. If improvement in detection rates is desired, additional programs are necessary. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Beschichtung von metallischen Membranen mittels Pulsed Laser Deposition
Authors: Lackner J.M. , Mukherji D. , Waldhauser W. , Wanderka N. , Kardjilov N. , Näth O. , Jäger S. , Schmitz F. , Rösler J.
Published: August 2008

Der Funktionalisierung von meso‐ und nanoporösen Werkstoffen durch Beschichtungen kommt zunehmend größere Bedeutung zu. So kann z.B. deren Porenoberfläche hinsichtlich der Biokompatibilität oder dem katalytischen Verhalten modifiziert werden. Derzeit sind dafür vor allem CVD‐Verfahren im Einsatz. Die vorliegende Arbeit zeigt jedoch am Beispiel der Pulslaserbeschichtung (PLD)‐‐ einem PVD‐Verfahren —, dass nanoporöse Membranen auf Ni3Al‐Basis und Porendimensionen von etwa 200 nm mit hoher Schichtdicken‐Homogenität und Schichthaftung von diamantähnlichen Kohlenstoffschichten bei geringen Membrandicken beschichtet werden können.
Beschichtungen für Zahnräder
Authors: Petrik Marko , Wittdorf Ralf , Thomsen Helge , Kaestner Peter , Kropp Jan Peter
Published: August 2008

Um das Ziel zu erreichen, Stahlzahnräder hinsichtlich Tragfähigkeit und Verschleiß zu optimieren, wurden in diesem Vorhaben Beschichtungen erprobt. Im Rahmen von Vorarbeiten wurden verschiedene Schichtsysteme numerisch mit der Software ELASTICA® auf ihre Eignung geprüft. Dabei wurden die Eigenschaften der Schichtsysteme abhängig vom Werkstoff, seiner Oberflächenbehandlung sowie den Radien relevanter Wälzpartner bestimmt. Unterschieden wurden makroskopische Wälzkontakte zwischen den Zahnflanken sowie mikroskopische Kontakte mit Oberflächenrauheit sowie Abriebpartikeln. Die vier am besten geeigneten Schichtsysteme wurden zunächst auf vereinfachte Rollkörper aufgetragen und unter verschiedenen Bedingungen geprüft. Dadurch wurden zwei Schichtsysteme ermittelt, die besondere Eignung für die Beschichtung der Zahnräder zeigen: a:C‐H mit CrN‐Stützschicht sowie a:C‐H mit CrN‐Stützschicht und vorhergehender Plasmanitrierung (Duplex‐Prozess). Um die Schichten auf den Zahnflanken gegen Eingriffsstöße zu schützen, wurde deren evolventisches Profil mit einer Kopfrücknahme versehen. Als Zahnradwerkstoffe wurden 16MnCr5, 42CrMo4 sowie der Sonderstahl ETG®88 eingesetzt. Als Schmiermittel kamen zwei Arten von Fließfetten zum Einsatz. Zudem wurde der Trockenlauf untersucht. Die Zahnräder wurden bei drei verschiedenen Drehzahlen geprüft. Geprüft wurden die Zahnräder auf einem eigens dafür konstruierten Prüfstand. Die Prüfung verlief in sogenannten Kraftstufen. Jede Stufe steht für eine feste Anzahl von Wälzkontakten, d. h. Umdrehungen der Zahnräder, sowie für ein bestimmtes Drehmoment, das eine Hertz'sche Pressung auf den Zahnflanken hervorruft. Mit steigender Stufenzahl wird das Drehmoment erhöht. Das Schadenskriterium ist der Beginn des Fressens des Grundwerkstoffs als Indikator, dass das jeweilige Schichtsystem seine Schutzwirkung eingebüßt hat. Die Versuchsergebnisse zeigten, dass insbesondere bei den Stählen 16MnCr5 und 42CrMo4 das Schichtsystem a:C‐H mit CrN‐Stützschicht und vorhergehender Plasmanitrierung zu nennenswerten Steigerungen der Flankentragfähigkeit und des Verschleißschutzes führt. Diese Steigerung wurde sowohl bei fettgeschmierten als auch bei trockenlaufenden Zahnrädern beobachtet. Die Ergebnisse für den Sonderstahl ETG®88 fielen weniger gut aus.

Durch die beschriebenen Beschichtungen konnte ein Trockenlauf ermöglicht werden, der ohne Beschichtung nicht denkbar gewesen wäre. Die Ergebnisse reichen aber noch nicht ganz an die Ergebnisse der unbeschichteten Zahnräder bei Verwendung additivierten Fettes bei Minimalmengenschmierung heran. Gründe dafür sind in einer unzureichenden Nitrierhärtetiefe zu sehen. Für die gewählten Stähle wurden deshalb die Nitrierparameter hinsichtlich der Nitrierhärtetiefe angepasst. Nach der Auswertung der Versuche mit optimal nitrierten Zahnrädern ist es dann möglich, Empfehlungen für die Plasmanitrierung, die notwendige Beschichtung sowie die Auswahl des Fettes zu geben.
Regulatory processes and population cyclicity in laboratory populations of Anagasta Kühniella (Zeller) (Lepidoptera: Phycitidae) II. Parasitism, predation, competition and protective cover
Authors: White E. G. , Huffaker C. B.
Published: August 2008

The population dynamics of Anagasta kühniella has been studied in standardized conditions in replicated ecosystems in which the variables have been increased one at a time. Additional to the variables reported earlier (WHITE and HUFFAKER, 1969), the present ecosystems included larval and pupal parasitism by Venturia canescens, both in the presence and absence of the egg‐predator Blattisocius tarsalis, and also in the presence and absence of two levels of protective cover for the host. In the presence of V. canescens, parasitism was generally of major importance as a regulating instrument in determining host population densities and it characteristically produced cycling and discrete host generations that arose from a parasite‐induced discontinuity in the age‐structure of the host populations. When the predatory mite and/or protective cover was also present, modifying interactions arose but these were not sufficient to dispel completely the discontinuous age‐structure and the cycling induced by the parasite. The actual degree of protective cover was particularly important insofar as it modified the levels and patterns of parasitism and permitted competition for food among host larvae to assume greater importance in the collective regulating process.

Three forms of population cyclicity are described and discussed: a four‐generation cyclicity which was the basic pattern of cycling and occurred both in the presence and absence of protective cover; an eight‐generation cyclicity that arose from disturbed four‐generation cycling in the presence of a minimal level of host protection; and a nine‐generation cyclicity in which extensive protection compounded the collective nature of density‐dependent regulation.
Biology of hyphantria cunea drury (lepidoptera : Arctiidae) in Japan. IX. population dynamics
Authors: Itô Yosiaki , Shibazaki Atsuhiro , Iwahashi Osamu
Published: August 2008

Fluctuations in population density of Hyphantria cunea in Japan are characterized by a gradation‐like pattern. Analysis of the life table data taken from two stations during eight successive generations showed that (1) mortality during egg and early larval stages was density‐independent, (2) mortality during later larval stages was inversely density‐dependent, and (3) mortality during prepupal and pupal stages was density‐independent. Thus the overall mortality process from egg to adults eclosion was inversely density‐dependent. The inverse density‐dependence in mortality process during later larval instars was mainly attributed to the ‘escape’ (VOÛTE, 1946) of H. cunea populations from the predation pressure of polyphagous predators such as birds and Politses wasps. This inverse density‐dependence was considered to be a cause of gradation‐like fluctuation. Field collection of egg‐masses showed that the mean number of eggs per egg‐mass, which was believed to be a good representation of mean fecundity, varied from 425 to 1050 during 4 years. Density‐dependent reduction in the mean number of eggs per egg‐mass was demonstrated, and this reduction was a factor regulating the population density. Assuming fixed sex ratio and survival rate of adults, a preliminary population model was constructed. The number of eggs laid in the survey station could be predicted well by the model based on the number of eggs laid in the previous generation, in 9 out of 13 cases. An attempt to apply a model of the same type to mimic the fluctuation of abundance (peak number of larval colonies per tree) on road‐side trees suggested another density‐dependent process, that is, insecticide application by man. Discussion was also presented on the causes responsible for the turn of population trend from decreasing to increasing in the 1st generation of 1968.