bluuebunny/crossref_metadata_2025 huggingface dataset:
DnaJB6 is present in the core of Lewy bodies and is highly up‐regulated in parkinsonian astrocytes
Authors: Durrenberger P.F. , Filiou M.D. , Moran L.B. , Michael G.J. , Novoselov S. , Cheetham M.E. , Clark P. , Pearce R.K.B. , Graeber M.B.
Published: August 2008

DnaJ/Hsp40 chaperones determine the activity of Hsp70s by stabilizing their interaction with substrate proteins. We have predicted, based on the in silico analysis of a brain‐derived whole‐genome transcriptome data set, an increased expression of DnaJ/Hsp40 homologue, subfamily B, member 6 (DnaJB6) in Parkinson's disease (PD; Moran et al. [2006] Neurogenetics 7:1–11). We now show that DnaJB6 is a novel component of Lewy bodies (LBs) in both PD substantia nigra and PD cortex and that it is strongly up‐regulated in parkinsonian astrocytes. The presence of DnaJB6 in the center of LBs suggests an early and direct involvement of this chaperone in the neuronal disease process associated with PD. The strong concomitant expression of DnaJB6 in astrocytes emphasizes the involvement of glial cells in PD and could indicate a route for therapeutic intervention. Extracellular alpha‐synuclein originating from intravesicular alpha‐synuclein is prone to aggregation and the potential source of extracellular aggregates (Lee [2008] J. Mol. Neurosci. 34:17–22). The observed strong expression of DnaJB6 by astrocytes could reflect a protective reaction, so reducing the neuronal release of toxic alpha‐synuclein and supporting the astrocyte response in PD might limit the progression of the disease process. © 2008 Wiley‐Liss, Inc.
Effects of maternal antenatal glucocorticoid treatment on apoptosis in the ovine fetal cerebral cortex
Authors: Malaeb Shadi N. , Hovanesian Virginia , Sarasin Matthew D. , Hartmann Silvia M. , Sadowska Grazyna B. , Stonestreet Barbara S.
Published: August 2008

We examined the effects of single and multiple maternal glucocorticoid courses on apoptosis in the cerebral cortices of ovine fetuses (CC). Ewes received single dexamethasone or placebo courses at 104–106 or 133–135 days or multiple courses between 76–78 and 104–106 days gestation. In the single‐course groups, ewes received four 6 mg dexamethasone or placebo injections every 12 hr for 48 hr. Multiple‐course groups received the same treatment once per week for 5 weeks. Neuronal and nonneuronal apoptotic cell numbers per square millimeter were determined with TUNEL and NeuN staining and with caspase‐3 enzyme activity on CC tissues harvested at 106–108 (70%) or 135–137 (90%) days of gestation. Apoptotic cell numbers and caspase‐3 activity were 50% lower (P < 0.02) after single placebo courses at 90% than 70% gestation; 90% of apoptotic cells were (P < 0.01) nonneuronal at both ages. Nonneuronal apoptotic cells and caspase‐3 activity were 40% and 20% lower (P < 0.02) after single dexamethasone than placebo courses at 70%, but not 90%, gestation. Caspase‐3 activity was 20% lower (P < 0.01) after multiple dexamethasone than placebo courses, but apoptotic cell number did not differ. We conclude that nonneuronal apoptosis represents the major form of apoptosis in the CC at both 70% and 90% of gestation. Apoptosis in nonneuronal cells decreases with maturity and after a single course of dexamethasone at 70%, but not at 90%, gestation and not after multiple courses at 70% gestation. We speculate that a single course of glucocorticoids exerts maturational changes on the rate of apoptosis in the cerebral cortex of preterm ovine fetuses. © 2008 Wiley‐Liss, Inc.
Nitric oxide donor up‐regulation of SDF1/CXCR4 and Ang1/Tie2 promotes neuroblast cell migration after stroke
Authors: Cui Xu , Chen Jieli , Zacharek Alex , Roberts Cynthia , Yang Yuping , Chopp Michael
Published: August 2008

We tested the hypothesis that a nitric oxide donor, DETA‐NONOate, up‐regulates stromal cell‐derived factor‐1 (SDF1) and angiopoietin 1 (Ang1) in the ischemic brain and their respective receptors chemokine CXC motif receptor 4 (CXCR4) and Tie2 in the subventricular zone (SVZ) and thereby promote SVZ neuroblast cell migration after stroke. C57BL/6J mice were subjected to middle cerebral artery occlusion (MCAo), and 24 hr later DETA‐NONOate (0.4 mg/kg) or phosphate‐buffered solution was intravenously administered. Mice were sacrificed at 14 days for histological assessment or sacrificed at 3 days for analysis by real‐time polymerase chain reaction and migration after MCAo. To elucidate whether SDF1/CXCR4 and Ang1/Tie2 pathways mediate DETA‐NONOate‐induced SVZ migration after stroke, SDF1α, Ang1 peptide, a specific antagonist of CXCR4 (AMD3100), and a neutralizing antibody of Tie2 (anti‐Tie2) were used in vitro. DETA‐NONOate significantly increased the percentage area of doublecortin (DCX, a marker of migrating neuroblasts)‐immunoreactive cells in the SVZ and ischemic boundary zone. DETA‐NONOate significantly increased the expression of SDF1 and Ang1 in the ischemic border and up‐regulated CXCR4 and Tie2 in the SVZ compared with MCAo control. DCX‐positive cell migration from SVZ explants was significantly increased in the DETA‐NONOate treatment group compared with MCAo‐alone animals. In vitro, SDF1α and Ang1 significantly increased SVZ explants cell migration. In addition, inhibition of CXCR4 or Tie2 significantly attenuated DETA‐NONOate‐induced SVZ cell migration. Our data indicate that treatment of stroke with a nitric oxide donor up‐regulates SDF1/CXCR4 and Ang1/Tie2 pathways and thereby likely increases SVZ neuroblast cell migration. © 2008 Wiley‐Liss, Inc.
Immediate effects of prescribed burning, chopping and clearing on runoff, infiltration and erosion in a shrubland area in Galicia (NW Spain)
Authors: Fernández C. , Vega J. A. , Fonturbel T. , Jiménez E. , Pérez J. R.
Published: August 2008

The immediate effects of three different fuel management treatments on runoff, infiltration and erosion were evaluated in a mixed heathland in Galicia (NW Spain). The treatments compared were: prescribed burning, shrub chopping and shrub clearing.

Rainfall simulations were conducted immediately before and after fuel reduction treatments. A rainfall rate of 67 mm h−1 was applied for 30 min to each runoff plot.

Application of treatments significantly affected runoff and infiltration, but the parameter most affected by treatment was soil erosion, especially after prescribed burning. However, sediment yields measured immediately after treatments were low in all the cases, varying from 32 kg ha−1 after shrub clearing to 248 kg ha−1 after prescribed burning. In the rainfall simulation plots subjected to prescribed burning, the maximum temperatures reached at mineral soil surface during burns significantly affected soil losses. The organic layer remaining after treatments and soil moisture contents appeared to be critical variables in controlling runoff and erosion during the first rainfall event following fuel reduction treatments. When the remaining organic layer was removed just after treatments and a new rainfall simulation was carried out, mean infiltration rate trended to decrease and cumulative runoff and sediment yield tended to increase.

The above information could be useful for determining whether fuel management prescriptions are compatible with fire hazard reduction and soil conservation. Copyright © 2008 John Wiley & Sons, Ltd.
Second order problems with functional conditions including Sturm–Liouville and multipoint conditions
Authors: Cabada Alberto , O'Regan Donal , Pouso Rodrigo L.
Published: August 2008

In this paper we study the solvability of equations of the form

‐(d/dt)φ (t, u, u (t), u ′(t)) = f (t, u, u (t), u ′(t)) for a.e. t ∈ I = [a, b ],

together with functional‐boundary conditions which cover, amongst others, Sturm–Liouville and multipoint boundary data as particular cases. Our approach uses upper and lower solutions together with growth restrictions of Nagumo's type. An example is presented to show the applicability of the obtained results. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A unified approach for a class of problems involving a pseudo‐monotone operator
Authors: Jebelean Petru , Motreanu Dumitru , Motreanu Viorica Venera
Published: August 2008

In this paper we establish the solvability and approximation of a general inequality problem by means of a sequence of problems satisfying some compatibility conditions with respect to the initial one. The setting allows to unify and extend various existence results in the smooth and nonsmooth analysis. The approach mainly relies on Galerkin like approximations, pseudo‐monotone operators and topics from nonsmooth analysis. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimal quantization for dyadic homogeneous Cantor distributions
Authors: Kreitmeier Wolfgang
Published: August 2008

For a large class of dyadic homogeneous Cantor distributions in ℝ, which are not necessarily self‐similar, we determine the optimal quantizers, give a characterization for the existence of the quantization dimension, and show the non‐existence of the quantization coefficient. The class contains all self‐similar dyadic Cantor distributions, with contraction factor less than or equal to 1/3. For these distributions we calculate the quantization errors explicitly. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Boundedness of multilinear commutators of generalized fractional integrals
Authors: Mo Huixia , Lu Shanzhen
Published: August 2008

Let L be the infinitesimal generator of an analytic semigroup on L2(ℝn ) with Gaussian kernel bound, and let L–α /2 be the fractional integral of L for 0 < α < n. Suppose that b = (b1, b2, …, bm ) is a finite family of locally integral functions, then the multilinear commutator generated by b and L–α /2 is defined by

L–α /2bf = [bm , …, [b2, [b1, L–α /2]], …, ] f,

where m ∈ ℤ+. When b1, b2, …, bm ∈ BMO or bj ∈ Λ (0 < βj < 1) for 1 ≤ j ≤ m, the authors study the boundedness of L–α /2b. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the principal eigenvalue of degenerate quasilinear elliptic systems
Authors: Zographopoulos Nikolaos B.
Published: August 2008

We study the properties of the positive principal eigenvalue of a degenerate quasilinear elliptic system. We prove that this eigenvalue is simple, unique up to positive eigenfunctions and isolated. Under certain restrictions on the given data, the regularity of the corresponding eigenfunctions is established. The extension of the main result in the case of an unbounded domain is also discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonlinear Riemann–Hilbert problems with circular target curves
Authors: Glader Christer , Wegert Elias
Published: August 2008

The paper gives a systematic and self‐contained treatment of the nonlinear Riemann–Hilbert problem with circular target curves |w–c| =r, sometimes also called the generalized modulus problem. We assume thatcandrare Hölder continuous functions on the unit circle and describe the complete set of solutionswin the disk algebraH∞∩Cand in the Hardy spaceH∞of bounded holomorphic functions.

The approach is based on the interplay with the Nehari problem of best approximation by bounded holomorphic functions. It is shown that the considered problems fall into three classes (regular, singular, and void) and we give criteria which allow to classify a given problem.

For regular problems the target manifold is covered by the traces of solutions with winding number zero in a schlicht manner. Counterexamples demonstrate that this need not be so if the boundary condition is merely continuous.

Paying special attention to constructive aspects of the matter we show how the Nevanlinna parametrization of the full solution set can be obtained from one particular solution of arbitrary winding number. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Macromol. Rapid Commun. 16/2008
Authors: Shunmugam Raja , Tew Gregory N.
Published: August 2008

Front Cover: The cover picture shows a cartoon representation of emission colors of terpyridine–lanthanide complexes attached along a polymer backbone. A recent study of these terpyridine‐containing polymers with various concentrations of Dy(III), Eu(III), and Tb(III) demonstrated the ability to generate a variety of colors, including true white light. Continued progress in synthetic chemistry and macromolecular characterization will enable advanced materials from these metal‐ligated polymers. Further details can be found in the article by R. Shunmugam and G. N. Tew* on page 1355. Dr. Morris Slutsky is acknowledged for assistance with the cover image.
Expression Profile of pha Gene Cluster of Pseudomonas putida KT2442
Authors: de Eugenio Laura I. , Escapa Isabel F. , Galán Beatriz , García José L. , Prieto María A.
Published: August 2008

Polyhydroxyalkanoates (PHAs) are biodegradable polymers that many bacteria accumulate as carbon and energy storage when growth conditions are unbalanced. Pseudomonas strains belonging to the rRNA homology group I such as P. putida can accumulate medium‐chain‐length‐PHA from monomers in the C8 to C10 range. Regulation of PHA synthesis and degradation in P. putida KT2442 has been studied using different molecular approaches. In this study six promoter regions located upstream of each pha gene were identified. The expression of the pha cluster have been analysed in the presence of octanoic acid versus glucose in the culture medium. Results demonstrated that the system is activated in the presence of octanoic acid as PHA precursor.
Conformational Dynamics of Poly(acrylic acid)‐Bovine Serum Albumin Polycomplexes at Different pH Conditions
Authors: Akkilic Namik , Mustafaev Mamed , Chegel Volodymyr
Published: August 2008

This work presents the real time surface plasmon resonance (SPR) and fluorescence spectroscopy observation of cooperative interactions between aggregate‐forming bovine serum albumin (BSA) and oppositely charged linear macromolecule poly(acrylic) acid (PAA). Interactions between protein and polymer result in formation of polyelectrolyte‐protein polycomplexes, which exhibit expressed conformational transformations, especially at low pH. The rate constants of observed kinetic transformations were calculated and found to vary in the range from 0.8 × 10−3 to 6.7 × 10−3 for different pH values. The processes of aggregation, sedimentation and conformation of BSA‐PAA complex are discussed.
Soybean allergen detection methods – A comparison study
Authors: Pedersen Mona H. , Holzhauser Thomas , Bisson Caroline , Conti Amedeo , Jensen Louise B. , Skov Per S. , Bindslev‐Jensen Carsten , Brinch Ditte S. , Poulsen Lars K.
Published: August 2008

Soybean containing products are widely consumed, thus reliable methods for detection of soy in foods are needed in order to make appropriate risk assessment studies to adequately protect soy allergic patients. Six methods were compared using eight food products with a declared content of soy: a direct sandwich ELISA based on polyclonal rabbit antibody (ab) to raw soy flakes, a commercial and an in‐house competitive ELISA both based on ab to denatured, ‘renatured’ soy protein, an enzyme‐allergosorbent test (EAST) inhibition based on two sera from soy allergic patients, histamine release (HR) using basophils passively sensitized with patient serum and a PCR method detecting soy DNA. Eight food products were selected as model foods to test the performance of the methods. There was an overall good agreement between the methods in terms of ranks of soy content but not the quantity. The sandwich ELISA aimed at native soy proteins had the lowest detection limit of 0.05 ppm, but only identified soy in 5/8 products, and generally in lower amounts compared to other methods. The competitive ELISA had a higher detection limit of 21 ppm, but seemed more successful in detecting processed soy. Only HR, EAST inhibition and PCR detected soy in all eight products. In spite of a general good correlation in terms of ranks of soy content, more than a single method may be necessary to confirm the presence of soy in foods.
An error‐estimate‐free and remapping‐free variational mesh refinement and coarsening method for dissipative solids at finite strains
Authors: Mosler J. , Ortiz M.
Published: August 2008

A variational h‐adaptive finite element formulation is proposed. The distinguishing feature of this method is that mesh refinement and coarsening are governed by the same minimization principle characterizing the underlying physical problem. Hence, no error estimates are invoked at any stage of the adaption procedure. As a consequence, linearity of the problem and a corresponding Hilbert‐space functional framework are not required and the proposed formulation can be applied to highly non‐linear phenomena. The basic strategy is to refine (respectively, unrefine) the spatial discretization locally if such refinement (respectively, unrefinement) results in a sufficiently large reduction (respectively, sufficiently small increase) in the energy. This strategy leads to an adaption algorithm having O(N) complexity. Local refinement is effected by edge‐bisection and local unrefinement by the deletion of terminal vertices. Dissipation is accounted for within a time‐discretized variational framework resulting in an incremental potential energy. In addition, the entire hierarchy of successive refinements is stored and the internal state of parent elements is updated so that no mesh‐transfer operator is required upon unrefinement. The versatility and robustness of the resulting variational adaptive finite element formulation is illustrated by means of selected numerical examples. Copyright © 2008 John Wiley & Sons, Ltd.
Preparation of ion conductive inorganic–organic composite systems by in situ sol–gel reaction of polymerizable ionic liquids
Authors: Mizumo Tomonobu , Watanabe Takeshi , Matsumi Noriyoshi , Ohno Hiroyuki
Published: August 2008

Inorganic–organic composites that conduct lithium ions were prepared by in situ sol–gel processing, with polymerizable ionic liquids and functional silicate or borosilicate network. In the presence of lithium salts, radical polymerization of 1‐ethyl‐3‐vinylimidazolium bis(trifluoromethane sulfonyl) imide ([evim][Tf2N]) was performed in parallel with the hydrolysis/polycondensation reaction of tetramethoxysilane (TMOS) with various trialkoxyboranes such as trimethoxyboran (TMOB), triisopropoxyborane (TiPOB) or mesityldimethoxyborane (Mes‐DMOB). Many of the resulting composites were obtained as transparent or translucent glass‐like solids. The composites had high decomposition temperatures above 300°C, due to the high thermal stability of both the inorganic network and the polymerized ionic liquids. The ionic conductivity was increased by increasing the fraction of organic compounds. The ionic conductivity of the compound was also altered by the addition of LiTf2N, up to at least 10−5 S cm−1 at room temperature. The ionic conductivity of the LiSO3CF3 doped system was about one order of magnitude less than that. The ionic conductivity was found to be influenced by the boron content of the inorganic matrix. Interaction between the triflate anion and the empty p‐orbital of boron may enhance the salt dissociation. This interaction appears to increase the lithium ion transference number. In situ sol–gel processing is a valuable way to provide mechanical strength, as well as specific functions, of polymerized ionic liquids. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis, characterization, and electrorheological properties of polyindene/calcium carbonate composites
Authors: Sarikaya Seyma , Yavuz Mustafa , Yilmaz Hasim , Unal H. Ibrahim , Sari Bekir
Published: August 2008

In this study, synthesis, characterization, and electrorheological (ER) properties of polyindene (PIn) and PIn/calcium carbonate (PIn/CaCO3) conducting composites were carried out by free radical polymerization. In the experiments, FeCl3 was used as oxidizing agent and the ratio of salt:monomer was 2:1. First, PIn was synthesized and obtained with 70% yield. Then, PIn/CaCO3 composites containing various amounts of PIn were prepared. PIn and PIn/CaCO3 composites were characterized by FTIR spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), dynamic light scattering (DLS) methods, Gouy Balance, and dielectric measurements. Suspensions of PIn and PIn/CaCO3 composites were prepared in silicone oil (SO), at a series of concentrations (c = 10–25%, m/m) and their sedimentation stabilities were determined. The effects of dispersed particle concentration, particle size, shear rate, external electric field strength, frequency, and temperature onto ER activities of suspensions were investigated. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Structure and properties of starch nanocrystal‐reinforced soy protein plastics
Authors: Zheng Hua , Ai Fujin , Chang Peter R. , Huang Jin , Dufresne Alain
Published: August 2008

Pea starch nanocrystals (StNs) were incorporated into a soy protein isolate (SPI) matrix to produce a class of full‐biodegradable nanocomposites. The StN with low loading level (2 wt%) showed a predominant reinforcing function, resulting in an enhancement in strength and Young's modulus. This was attributed to uniform dispersion of StN in the amorphous region of the SPI matrix, as well as maintaining stress of the rigid StN and transfer of stress mediated by interfacial interaction between the active StN surface and the SPI matrix. As a result, the nanocomposite containing 2 wt% StN had the maximum strength and Young's modulus in all the materials. With an increase in StN content, the number and the size of StN domains simultaneously increased due to a strong self‐aggregation tendency of StN. It lowered the effective active StN surface for interaction with the SPI matrix and destroyed the ordered structure in the SPI matrix, resulting in a gradual decrease of strength and Young's modulus. The introduction of relatively hydrophilic StN did not cause an obvious decrease of water resistance for any of the nanocomposites. The water uptake behavior of all the nanocomposites similar to that of neat SPI material was attributed mainly to the strong interfacial interaction between the StN filler and the SPI matrix. POLYM. COMPOS., 2009. Published by the 2008 Society of Plastics Engineers
Fabrication of core‐shell Fe3O4/polypyrrole and hollow polypyrrole microspheres
Authors: Lu Xiaofeng , Mao Hui , Zhang Wanjin
Published: August 2008

A facile synthesis of highly‐regulated core‐shell Fe3O4/polypyrrole (PPy) microspheres is achieved using a surfactant directed chemical oxidation polymerization in aqueous solution. The thickness of the PPy layer can be tuned by the quantity of the pyrrole monomer. The formation of core‐shell Fe3O4/PPy microspheres lies on the static interactions between the SO3− group in sodium dodecyl sulphate molecules and Fe3O4 microspheres. Other surfactants such as cetyltrimethylammonium bromide and polyoxyethylene (10) isooctylcyclohexyl ether (Triton X‐100) directed polymerization cannot produce such highly‐regulated core‐shell Fe3O4/PPy microspheres. XPS spectra proved the core‐shell structure of the composite microspheres. XRD, FTIR, and UV–vis spectra are used to characterize the chemical structure of the composite microspheres. The electrical and magnetic properties are also investigated. Moreover, the obtained core‐shell Fe3O4/PPy microspheres can be converted to highly‐regulated hollow PPy microspheres by dissolving the Fe3O4 core with acid solution. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Ion beam induced charge (IBIC) irradiation damage study in synthetic single crystal diamond using 2.6 MeV protons
Authors: Lohstroh A. , Sellin P. J. , Gkoumas S. , Parkin J. , Veeramani P. , Prekas G. , Veale M. C. , Morse J.
Published: August 2008

We have studied the effects of irradiation induced damage on the detector response of a synthetic single crystal diamond radiation detector. Before introducing radiation damage, the spatial variation of the detector response was investigated using a highly focused 2.6 MeV proton beam. A very uniform response close to 100% charge collection efficiency (CCE) over the whole contact area was found at applied electric field strengths as low as 0.4 V μm–1. At lower biases, time dependent polarisation phenomena were observed and clearly reduced the average signal amplitude. Subsequently, the 2.6 MeV proton beam has been used to introduce radiation damage within selected areas. The ion beam induced charge imaging was repeated to probe the modified regions. Even at an applied electric field of 2.6 V μm–1, no signal above the analogue threshold of the system was observed in the areas which had received a dose larger then 5 × 1014 cm–2, whereas more than 90% CCE was reached in the area with 1012 protons cm–2. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrical characterization of locally charged oxidized nanocrystalline diamond films by Kelvin force microscopy
Authors: Cˇermák J. , Kromka A. , Rezek B.
Published: August 2008

A nanocrystalline diamond (NCD) thin film is deposited on a gold electrode and oxygen terminated by r.f. oxygen plasma. An atomic force microscope (AFM) is used to induce electrostatically charged micrometer‐sized areas on the diamond film by applying bias voltages in the range between –30 V and +30 V on the AFM tip during scanning in contact mode. Trapped charge was detected by Kelvin force microscopy showing a contact potential difference of 150 mV for both polarities. Decrease of surface potential by 20 mV in the positively charged area and by 90 mV in the negatively charged area is observed after 15 h under ambient conditions. Possible charge trapping mechanisms are discussed in terms of electret‐like or semiconductor‐like behavior of NCD thin films. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermal conductivity of polycrystalline CVD diamond: effect of annealing‐induced transformations of defects and grain boundaries
Authors: Inyushkin A. V. , Taldenkov A. N. , Ralchenko V. G. , Vlasov I. I. , Konov V. I. , Khomich A. V. , Khmelnitskii R. A. , Trushin A. S.
Published: August 2008

Polycrystalline CVD diamond has been annealed in vacuum at temperatures tan = 1550 °C–1690 °C to investigate an influence of modifications of grain boundaries (GB) and defects on thermal conductivity and optical properties of originally optical quality material. While the sample was converted by this heat treatment to “black diamond”, excitons still could be observed in cathodoluminescence spectra. Photoluminescence spectra revealed an aggregation of nitrogen (formation of H3 optical center) after annealing at 1690 °C. In‐plane thermal conductivity k (T) measured by a heated bar method in the temperature range T = 5–410 K shows a strong (up to 5 times) and monotonic decrease at T < 45 K upon annealing, while room temperature k (298 K) value remains almost constant (ca. 19.0 W/cm K) till tan = 1650 °C, rapidly degrading at higher tan. The experimental data on thermal conductivity are analyzed in the framework of full Callaway theory taking into account three‐phonon scattering processes, phonon scattering on point defects, sample boundaries, and GB. The proposed model reproduces well the observed k (T) behavior, the phonon scattering on the modified GB playing an important role. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Understanding the local and global impacts of model physics changes: an aerosol example
Authors: Rodwell Mark J. , Jung Thomas
Published: August 2008

This study demonstrates the use of a package of diagnostic techniques to understand the local and global responses to a given physics change within a general circulation model. Here, the package is applied to the case of a change in the aerosol climatology in the forecast model of the European Centre for Medium‐range Weather Forecasts. The largest difference between old and new climatologies is over the Sahara where, in particular, soil‐dust aerosol is reduced. Conventional diagnostics show that the change lead to improvements in local medium‐range forecast skill and reductions in seasonal‐mean errors throughout the globe. To study the local physics response, short‐range tendencies in weather forecasts are diagnosed. These tendencies are decomposed into the contributions from each physical process within the model. The resulting ‘initial tendency’ budget reveals how the local atmosphere responds to the aerosol change. The net tendencies also provide strong evidence to confirm that the new aerosol climatology is superior. Seasonal integrations demonstrate that the tropic‐wide response can be understood in terms of equatorial waves and their enhancement by diabatic processes. The so‐called ‘Rossby‐wave source’ is made applicable to general circulation models and used to understand how the tropical anomalies subsequently impact on the global circulation. The mean response in the extratropics is found to be a stationary wave field. Precipitation anomalies that are co‐located with extratropical divergent vorticity sources suggest the possibility for diabatic modification of the tropically forced Rossby‐wave response. Copyright © 2008 Royal Meteorological Society
Evaluation of irrigation canal networks to assess stream connectivity in a watershed
Authors: Colvin Michael E. , Moffitt Christine M.
Published: August 2008

We used digital data sets, aerial photos and direct field observations in a geographical information system to evaluate the stream habitat in an Idaho watershed affected by agriculture. We found that the scale of the digital data sets affected the outcome of the assessment due to the presence of dewatered stream channels in the drainage. We analysed the spatial configuration of irrigation canals in the watershed to determine if the contemporary stream network connectivity could be attributed to human‐ caused or to natural hydrological processes. Many irrigation canals were significantly longer than would have been expected if these canals were constructed to capture water from the closest portion of the abandoned stream channels. Our findings provide evidence that some of these tributary streams had reaches that were likely ephemeral or intermittent at the time of canal construction. Our approach for assessing stream and irrigation network connectivity in pastoral and agricultural lands should aid managers in prioritizing the effective and appropriate reconnection efforts. Published in 2008 by John Wiley & Sons, Ltd.
A reach‐scale remote sensing technique to relate wetland inundation to river flow
Authors: Frazier Paul , Page Ken
Published: August 2008

Knowledge of the relationship between river flow and wetland inundation at a reach‐scale is important for effective flow management, particularly, for environmental outcomes. Historical remotely sensed data, such as Landsat TM, provide the potential to determine the relationship between flow and wetland inundation for extended river reaches. In this paper we apply, adapt and evaluate a technique using sets of before‐flood and after‐flood image pairs to relate river flow to wetland inundation on a 640 km reach of the mid‐Murrumbidgee River, Australia. Stratification of the complete reach into relatively uniform sub‐reaches on the basis of hydrology and geomorphology was undertaken as a key pre‐analysis step. Analysis of flood wave attenuation within each sub‐reach showed that flood peaks entering and leaving a reach were highly correlated. Therefore, we argue that a flood peak measured at a single gauge within the reach can be used to provide a reliable indication of the behaviour of similar sized floods within the reach. The remote sensing technique proved capable of producing a model relating wetland inundation thresholds to flood peak discharge for each sub‐reach within the extended river reach. Although the model simplifies the complex relationship between river flow and wetland inundation, reliable key wetland inundation flow thresholds were determined. Copyright © 2008 John Wiley & Sons, Ltd.
Impact of partial removal of the invasive macrophyte Lagarosiphon major (hydrocharitaceae) on invertebrates and fish
Authors: Bickel Tobias O. , Closs Gerard P.
Published: August 2008

Invasive macrophyte species are a threat to native biodiversity and often grow to nuisance levels, therefore, making control options necessary. Macrophyte control can have pronounced impacts on littoral fish by reducing habitat heterogeneity and the loss of profitable (high density of invertebrates) foraging areas. Yet, there is little known about the impacts of macrophyte removal on invertebrates themselves. We conducted a macrophyte removal experiment, that is the cutting of channels into dense macrophyte beds, to investigate the impact of mechanical macrophyte control on invertebrate and fish communities in a littoral zone dominated by the invasive macrophyte Lagarosiphon major. The effect of macrophyte removal had only a temporary effect on macrophyte areal cover (4 months). Nevertheless, the treatment increased light penetration significantly. However, we could not detect any difference in epiphyton biomass. Invertebrate biomass increased in macrophyte stands 4 months after treatment and there was a shift in the invertebrate community composition. Mechanical control had no effect on invertebrate biodiversity. The higher invertebrate biomass did not translate into a higher fish density in the treated areas. The results of this study indicated that partial mechanical removal is a suitable option to control unwanted macrophyte stands. Copyright © 2008 John Wiley & Sons, Ltd.
Comparison of methods for analysing salmon habitat rehabilitation designs for regulated rivers
Authors: Brown Rocko A. , Pasternack Gregory B.
Published: August 2008

River restoration practices aiming to sustain wild salmonid populations have received considerable attention in the Unites States and abroad, as cumulative anthropogenic impacts have caused fish population declines. An accurate representation of local depth and velocity in designs of spatially complex riffle‐pool units is paramount for evaluating such practices, because these two variables constitute key instream habitat requirements and they can be used to predict channel stability. In this study, three models for predicting channel hydraulics—1D analytical, 1D numerical and 2D numerical—were compared for two theoretical spawning habitat rehabilitation (SHR) designs at two discharges to constrain the utility of these models for use in river restoration design evaluation. Hydraulic predictions from each method were used in the same physical habitat quality and sediment transport regime equations to determine how deviations propagated through those highly nonlinear functions to influence site assessments. The results showed that riffle‐pool hydraulics, sediment transport regime and physical habitat quality were very poorly estimated using the 1D analytical method. The 1D and 2D numerical models did capture characteristic longitudinal profiles in cross‐sectionally averaged variables. The deviation of both 1D approaches from the spatially distributed 2D model was found to be greatest at the low discharge for an oblique riffle crest with converging cross‐stream flow vectors. As decision making for river rehabilitation is dependent on methods used to evaluate designs, this analysis provides managers with an awareness of the limitations used in developing designs and recommendations using the tested methods. Copyright © 2008 John Wiley & Sons, Ltd.
Aussteifung von Gebäudehüllen durch eckgeklotzte Glasscheiben
Authors: Wellershoff Frank
Published: August 2008

Hinsichtlich seiner Festigkeit zeigt Glas eine große hnlichkeit zum Beton und kann ebenso wie dieser ca. 10 fach höhere Druckspannungen als Zugspannungen aufnehmen. Das Potential der hohen Druckfestigkeit des Glases wurde jedoch bislang nur in wenigen Sonderprojekten genutzt. Übliche Verglasungen in Gebäudehüllen werden ausschließlich durch Lasten beansprucht, die senkrecht zur Scheibenebene wirken und bemessungsrelevante Oberflächenzugspannungen hervorrufen. Die Möglichkeit einer gleichzeitigen Übertragung von Druckkräften in der Scheibenebene könnte genutzt werden, um die Gebäudehülle auszusteifen oder um ein seitliches Ausweichen von Pfosten und Riegeln zu verhindern.

Für das hier betrachtete System wurden neue Eckklotzungsdetails konzipiert und getestet. Das Tragverhalten von quadratischen Glasscheiben unter kombinierten Belastungen in der Scheibenebene und senkrecht zur Scheibenebene wurde analysiert und Bemessungsmodelle entwickelt. Die Verzweigungslast von eckgeklotzten, monolithischen Scheiben unter diagonaler Druckkraft konnte mit der Energiemethode analytisch bestimmt werden.
Schweißen ermüdungsbeanspruchter Altstahlkonstruktionen – Untersuchungen zum Sprödbruchverhalten geschweißter Verbindungen aus Flussstahl
Authors: Lüddecke Falk , Mehdianpour Milad , Graße Wolfgang
Published: August 2008

Beim Schweißen wird durch die induzierte Kerbschärfe und die Eigenspannungen die Gefahr eines Sprödbruchs erhöht. Aufgrund der verringerten Zähigkeitseigenschaften von alten Flussstählen im Vergleich zu heutigen Baustählen ist daher eine Bewertung der Sprödbruchgefahr von Flussstählen nach dem Schweißen erforderlich. Für eine Bewertung auf bruchmechanischem Niveau wird der Spannungsintensitätsfaktor auf der Beanspruchungsseite mit der Bruchzähigkeit auf der Widerstandsseite verglichen. Für einen Großteil der früher verbauten Bleche bis 11 mm Dicke kann gezeigt werden, dass kein Sprödbruch zu erwarten ist. Darüber hinaus werden für größere Blechdicken Daten aufbereitet, die auf Basis der tatsächlich vorliegenden Materialbeanspruchbarkeiten und rechnerisch ermittelten Beanspruchungen eine Bewertung ermöglichen.
Experimentelle Tragfähigkeitsüberprüfung von Plattenmaterial Hohlkammerpolycarbonat 16 mm
Authors: Jahnke Hartwig , Jordan Sandra , Klink Thomas
Published: August 2008

Um die Vermietbarkeit von Geschosswohnungen zu verbessern, werden zunehmend Balkone an Wohnhäuser angebaut. Fenster werden dabei zu Balkontüren umgestaltet. Der oberste Balkon soll dabei stets ein Dach erhalten. Das Dach besteht aus Plattenmaterial Hohlkammerpolykarbonat 16 mm, aufgelegt auf Vierkantprofilen. Ein statischer Nachweis für die Auflagerung und Befestigung der Hohlkammerplatten in den Vierkantprofilen, im Gegensatz zu dem Plattenmaterial selbst, kann nicht geführt werden. Da seitens des Balkonherstellers gewünscht wird, die Balkone deutschlandweit aufstellen zu können, muss die zulässige Belastung des Balkondaches experimentell ermittelt werden. Abgeleitet aus der Bruchlast im Belastungsversuch werden mit einem Sicherheitsfaktor von γ = 2,0 sowohl die zulässige Schnee‐ als auch die Windlast errechnet.
Elevated synaptophysin I in the prefrontal cortex of human chronic alcoholics
Authors: Henriksson Richard , Kuzmin Alexander , Ökvist Anna , Harper Clive , Sheedy Donna , Garrick Therese , Yakovleva Tatjana , Bakalkin Georgy
Published: August 2008

Convergent lines of evidence suggest potentiation of glutamatergic synapses after chronic ethanol exposure, and indicate that the presynaptic effect hereof is on modulators of synaptic strength rather than on executors of glutamate release. To address this hypothesis in the context of ethanol dependence in humans, we used semiquantitative immunoblotting to compare the immunoreactivities of synaptophysin I, syntaxin 1A, synaptosome‐associated protein 25, and vesicle‐associated membrane protein in the prefrontal and motor cortices between chronic alcoholics and control subjects. We found a region‐specific elevation in synaptophysin I immunoreactivity in the prefrontal cortex of alcoholics, but detected no significant differences between the groups in the immunoreactivities of the other three proteins. Our findings are consistent with an effect of repeated ethanol exposure on modulators of synaptic strength but not on executors of glutamate release, and suggest a role for synaptophysin I in the enduring neuroplasticity in the prefrontal cortical glutamate circuitry that is associated with ethanol dependence. Synapse 62:829–833, 2008. © 2008 Wiley‐Liss, Inc.
Multidimensional social control variables as predictors of drunkenness among French adolescents
Authors: Bègue Laurent , Roché Sebastian
Published: August 2008

Background

Previous studies of the determinants of drunkenness among youth investigated the contribution of a limited range of variables measuring social control. For the first time in France, this study including 1295 participants aged 14–19 years aimed at assessing the relative contribution of a broad range of multidimensional variables relating to social control such as parental and school functioning, conventional and religious beliefs, and activity level, in a single model predicting self‐reported drunkenness episodes.

Methods

A logistic regression model based on a survey involving nearly 50 measures selected at the first step was conducted using a backward elimination procedure to identify the significant predictors of drunken experience controlling for age, gender and SES among a sample of French adolescents.

Results

We found a protective effect of attachment and commitment to institutions in drunkenness experience among youth. Previous findings on parental variables were confirmed with qualifications, whereas the effect of religion was limited. The negative role of sport practice and impulsivity was also emphasized for some participants.
Predicting adolescent suicidality: Comparing multiple informants and assessment techniques
Authors: Connor Jennifer , Rueter Martha
Published: August 2008

Adolescent suicidality is a serious problem among American youth. Common risk factors for adolescent suicidality include depression and conduct problems but there is little agreement on the best means to assess these factors. We compared multiple informants (mothers, fathers, the adolescent and a sibling) and multiple assessment techniques using a sample of more than 460 families. Assessment techniques included paper–pencil instruments, observer ratings, and diagnostic interviews. Suicidality was assessed concurrently and two years after the risk assessment. Adolescent‐reported paper–pencil instruments and diagnostic interviews were strongly associated with concurrent and future suicidality. Parents' report of adolescent feelings and behaviors were also useful. Observed behaviors were not useful in assessing suicidality risk factors. Clinical recommendations include utilizing paper–pencil and diagnostic adolescent risk factor assessment and focusing on emotions.
Student engagement and its relationship with early high school dropout
Authors: Archambault Isabelle , Janosz Michel , Fallu Jean‐Sébastien , Pagani Linda S.
Published: August 2008

Although the concept of school engagement figures prominently in most school dropout theories, there has been little empirical research conducted on its nature and course and, more importantly, the association with dropout. Information on the natural development of school engagement would greatly benefit those interested in preventing student alienation during adolescence. Using a longitudinal sample of 11,827 French‐Canadian high school students, we tested behavioral, affective, cognitive indices of engagement both separately and as a global construct. We then assessed their contribution as prospective predictors of school dropout using factor analysis and structural equation modeling. Global engagement reliably predicted school dropout. Among its three specific dimensions, only behavioral engagement made a significant contribution in the prediction equation. Our findings confirm the robustness of the overall multidimensional construct of school engagement, which reflects both cognitive and psychosocial characteristics, and underscore the importance attributed to basic participation and compliance issues in reliably estimating risk of not completing basic schooling during adolescence.
Early and middle adolescents' disclosure to parents about activities in different domains
Authors: Smetana Judith G. , Villalobos Myriam , Tasopoulos‐Chan Marina , Gettman Denise C. , Campione‐Barr Nicole
Published: August 2008

Disclosure, disclosure strategies, and justifications for nondisclosure for prudential, peer, multifaceted, and personal acts were assessed using a sorting task with 118 lower‐middle class early and middle adolescents (Ms = 12.77 and 15.68 years). Adolescents were less involved in prudential than other behaviors, although prudential behavior was greater among middle than early adolescents; adolescents disclosed more about prudential and personal than multifaceted and peer behaviors. Nondisclosure was primarily due to concerns about parental disapproval (for prudential acts), claims that acts were personal or not harmful (for personal acts), and their mixture (for peer and multifaceted acts). When concerned about parental disapproval, older adolescents fully disclosed less (and lied somewhat more) than younger adolescents, whereas adolescents primarily avoided discussing the issue when they viewed acts as personal. Full disclosure was associated with better relationships with parents and less depressed mood; lying was associated with more parental behavioral control over personal issues and poorer relationships with fathers.
RNA interference of the BMPR‐IB gene blocks BMP‐2‐induced osteogenic gene expression in human bone cells
Authors: Singhatanadgit W. , Salih V. , Olsen I.
Published: August 2008

We have previously shown that human bone cells express bone morphogenetic protein receptor‐IB (BMPR‐IB). However, little is known about the precise role of this receptor in the response of osteoblastic genes to the BMP in these cells. To determine BMPR‐IB‐dependent osteoblastic gene expression, the present study examined the effects of BMPR‐IB knockdown on BMP‐induced osteoblast‐associated genes. BMPR‐IB mRNA and protein were markedly suppressed by transfection of cells with BMPR‐IB siRNA. Using three different bone cell samples, BMP‐2 stimulation of alkaline phosphatase (ALP), osteocalcin (OC), distal‐less homeobox‐5 (Dlx5) and core binding factor alpha‐1 (Cbfa1) was found to be specifically and significantly reduced in the BMPR‐IB siRNA‐transfected cultures compared with that of control cultures. Our study has provided evidence that BMPR‐IB‐dependent signaling plays a crucial role in BMP‐2 up‐regulation of the ALP, OC, Dlx5 and Cbfa1 genes in bone cells, suggesting a pivotal role of this receptor in BMP‐2‐induced osteoblast differentiation in vitro. These findings thus suggest the possibility that BMPR‐IB could be a therapeutic target for enhancing bone regeneration in vivo.
Temporal summation of pressure pain during muscle hyperalgesia evoked by nerve growth factor and eccentric contractions
Authors: Nie Hongling , Madeleine Pascal , Arendt‐Nielsen Lars , Graven‐Nielsen Thomas
Published: August 2008

Nerve growth factor (NGF) has a key role in the generation and potentiation of pain. Its centrally sensitizing effects may facilitate pain responses to noxious stimulus. This study assessed (1) the influence of NGF on delayed onset muscle soreness (DOMS) in shoulder muscles; and (2) the temporal summation of pressure pain during hyperalgesia induced by NGF and DOMS. In a blinded design, 10 healthy subjects were injected with NGF in the trapezius muscle on one side and with isotonic saline on the contralateral side as control. The subjects undertook shoulder eccentric exercise to induce DOMS in the shoulder muscles 3h after the injections. The soreness intensity to muscle contraction, pressure pain thresholds (PPT), and pain intensity to sequential stimuli (i.e. temporal summation at 1 and 30s inter‐stimulus interval (ISI)) were assessed before injections −3, 24h, and 4, 7, and 21 days after injections. The soreness intensity to muscle contraction significantly increased at 3 and 24h in both shoulders (P<0.05) and went back to baseline levels at day 7. The same development was seen in PPT as reduced thresholds (P<0.05). The NGF injected side had higher pain ratings during temporal summation at 1s ISI compared with the contralateral side 24h after injections. Intramuscular administration of NGF intensified the DOMS responses, evoking facilitated temporal summation. Central as well as peripheral sensitization mechanisms may play a role in the facilitation.