bluuebunny/crossref_metadata_2025 huggingface dataset:
LEARNING FROM LOCAL KNOWLEDGE: MODELING THE PASTORAL‐NOMADIC RANGE MANAGEMENT OF THE HIMBA, NAMIBIA
Authors: Müller Birgit , Linstädter Anja , Frank Karin , Bollig Michael , Wissel Christian
Published: October 2007

It is widely accepted that successful grazing management strategies in semiarid ecosystems need to be adapted to the highly temporal and spatially heterogeneous forage production. Nevertheless, a full understanding of the key factors and processes for sustainable adaptive management has yet to be reached. The investigation of existing, successful range management systems by simulation models may help to derive general understanding and basic principles.

The semi‐nomadic Himba in northern Namibia applied a sophisticated management system until the mid‐1990s which combined season‐dependent pasture use (resulting in rainy‐season pastures and dry‐season pastures), preservation of reserves for drought and sanctions for rule breaking. A stochastic ecological simulation model has been developed here which represents the main aspects of this management system. With this model we analyze (1) which components of the traditional Himba strategy are essential for sustainability and (2) what happens to the state of the rangeland system under socioeconomic changes.

This study shows that temporally and spatially heterogeneous pasture use yields higher productivity and quality of a pasture area than the pressure of homogeneous permanent grazing. Two aspects are of importance: (1) intra‐annual heterogeneous use (resting of the dry‐season pastures during the rainy season) and (2) interannual heterogeneous use (spatial extension of grazing in years of drought). This management system leads to an effective build‐up and use of a buffer in the system: the reserve biomass (the non‐photosynthetic reserve organs of the plants), an indicator for grazing and management history.

Analyzing purchase as one form of socioeconomic change, we demonstrate that easier market access to purchase livestock may lead to a decline in vegetation quality. However, cattle production increases as long as rest periods on parts of the pasture during the rainy season are granted.

Methodologically, we emphasize that simulation models offer an excellent framework for analyzing and depicting basic principles in sustainable range management derived from local knowledge. They provide the opportunity of testing whether these basic principles are also valid under different ecological and socioeconomic settings.
MERCURY BIOACCUMULATION AND TROPHIC TRANSFER IN SYMPATRIC SNAPPER SPECIES FROM THE GULF OF MEXICO
Authors: Bank Michael S. , Chesney Edward , Shine James P. , Maage Amund , Senn David B.
Published: October 2007

Consumption of marine fish is a major route of toxic methyl mercury (MeHg) exposure to ocean apex predators and human populations. Here we explore the influence of trophic structure on total mercury (Hg) accumulation in red snapper (RS, Lutjanus campechanus) and gray snapper (GS, Lutjanus griseus) from the coastal Louisiana region of the Gulf of Mexico, west of the Mississippi River. The objectives of this investigation were to: (1) determine the effectiveness of the use of offshore recreational fishing charter boats and marinas as sources of fish samples and (2) compare species differences in Hg bioaccumulation, trophic position, and carbon sources. Our data show that length‐normalized Hg concentrations (≥97% as MeHg in tissue of both species) were 230% greater in GS in comparison to RS collected from the same general area. Stable C and N isotope signatures (δ15N and δ13C) indicate that GS occupy a slightly higher trophic position (∼30% of one trophic position higher) on the Gulf food web in comparison to RS and that GS appear to incorporate higher trophic positioned prey, continually and at smaller sizes. Mercury was strongly correlated with combined δ15N and δ13C in pooled species data, arguing that most of the substantial difference in Hg bioaccumulation between RS and GS can be explained by modest differences in their trophic position and, to a lesser degree, carbon sources, which had low variation and high overlap among species. These observations demonstrate that even minor to moderate differences in trophic position and food habits in sympatric species can create relatively large differences in bioaccumulation regimes and underscores the importance of quantitative characterization of trophic structure in marine MeHg bioaccumulation studies.
Neuritin Mediates Nerve Growth Factor–Induced Axonal Regeneration and Is Deficient in Experimental Diabetic Neuropathy
Authors: Karamoysoyli Eugenia , Burnand Rebecca C. , Tomlinson David R. , Gardiner Natalie J.
Published: October 2007

OBJECTIVE—Axonal regeneration is defective in both experimental and clinical diabetic neuropathy, contributing to loss of axonal extremities and neuronal dysfunction. The mechanisms behind this failure are not fully understood; however, a deficit in neurotrophic support and signaling has been implicated.

RESEARCH DESIGN AND METHODS—We investigated the expression of neuritin (also known as candidate plasticity gene 15, cpg15) in the sensory nervous system of control rats and rats with streptozotocin (STZ)-induced diabetes using microarray PCR, Western blotting, and immunocytochemical analysis. The functional role of neuritin in sensory neurons in vitro was assessed using silencing RNA.

RESULTS—Neuritin was expressed by a population of small-diameter neurons in the dorsal root ganglia (DRG) and was anterogradely and retrogradely transported along the sciatic nerve in vivo. Nerve growth factor (NGF) treatment induced an increase in the transcription and translation of neuritin in sensory neurons in vitro. This increase was both time and dose dependent and occurred via mitogen-activated protein kinase or phosphatidylinositol-3 kinase activation. Inhibition of neuritin using silencing RNA abolished NGF-mediated neurite outgrowth, demonstrating the crucial role played by neuritin in mediating regeneration. Neuritin levels were reduced in both the DRG and sciatic nerve of rats with 12 weeks of STZ-induced diabetes, and these deficits were reversed in vivo by treatment with NGF.

CONCLUSIONS—Manipulation of neuritin levels in diabetes may therefore provide a potential target for therapeutic intervention in the management of neuropathy.
The Big-Fish-Little-Pond Effect: Persistent Negative Effects of Selective High Schools on Self-Concept After Graduation
Authors: Marsh Herbert W. , Trautwein Ulrich , Lüdtke Oliver , Baumert Jürgen , Köller Olaf
Published: October 2007

According to the big-fish-little-pond effect (BFLPE), attending academically selective high schools negatively affects academic self-concept. Does the BFLPE persist after graduation from high school? In two large, representative samples of German high school students (Study 1: 2,306 students, 147 schools; Study 2: 1,758 students, 94 schools), the predictive effects of individual achievement test scores and school grades on math self-concept are very positive, whereas the predictive effects of school-average achievement are negative (the BFLPE). Both studies showed that the BFLPE was substantial at the end of high school and was still substantial 2 years (Study 1) or 4 years (Study 2) later. In addition, because of the highly salient system of school tracks within the German education system, the authors are able to show that negative effects associated with school type (highly academically selective schools, the Gymnasium) were similar—but smaller—than the BFLPE based on school-average achievement.
Assessing No Child Left Behind and the Rise of Neoliberal Education Policies
Authors: Hursh David
Published: October 2007

No Child Left Behind and other education reforms promoting high-stakes testing, accountability, and competitive markets continue to receive wide support from politicians and public figures. This support, the author suggests, has been achieved by situating education within neoliberal policies that argue that such reforms are necessary within an increasingly globalized economy, will increase academic achievement, and will close the achievement gap. However, the author offers preliminary data suggesting that the reforms are not achieving their stated goals. Consequently, educators need to question whether neoliberal approaches to education should replace the previously dominant social democratic approaches.
Synthesis and Surface Engineering of Complex Nanostructures by Atomic Layer Deposition
Authors: Knez M. , Nielsch K. , Niinistö L.
Published: October 2007

Atomic layer deposition (ALD) has recently become the method of choice for the semiconductor industry to conformally process extremely thin insulating layers (high‐k oxides) onto large‐area silicon substrates. ALD is also a key technology for the surface modification of complex nanostructured materials. After briefly introducing ALD, this Review will focus on the various aspects of nanomaterials and their processing by ALD, including nanopores, nanowires and ‐tubes, nanopatterning and nanolaminates as well as low‐temperature ALD for organic nanostructures and biomaterials. Finally, selected examples will be given of device applications, illustrating recent innovative approaches of how ALD can be used in nanotechnology.
Solvent‐free reactions of alcohols with β‐dicarbonyl compounds catalyzed by iron(III) chloride
Authors: Yuan Yu , Shi Zhuangzhi , Feng Xuan , Liu Xiangnong
Published: October 2007

The direct substitution of alcohols and β‐dicarbonyl compounds was catalyzed with FeCl3 under solvent‐free conditions. The catalyst loading could be decreased to 0.01 mol% at high activities. It was shown that the reaction proceeded in two steps via the etherification of the alcohols. This method provided an easy and practical procedure for CC bond formation.Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis, Characterization and Antimycobacterial Activity of Ag(I)‐Aspartame, Ag(I)‐Saccharin and Ag(I)‐Cyclamate Complexes
Authors: Cavicchioli Maurício , Leite Clarice Q. F. , Sato Daisy N. , Massabni Antonio C.
Published: October 2007

The present work describes the synthesis and antimycobacterial activity of three Ag(I)‐complexes with the sweeteners aspartame, saccharin, and cyclamate as ligands, with the aim of finding new candidate substances for fighting tuberculosis and other mycobacterial infections. The minimal inhibitory concentration of these three complexes was investigated in order to determine their in‐vitro antimycobacterial activity against Mycobacterium tuberculosis, Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium malmoense, and Mycobacterium kansasii. The MIC values were determined using the Microplate Alamar Blue Assay. The best MIC values found for the complexes were 9.75 μM for Ag(I)‐aspartame against M. kansasii and 15.7 μM for Ag(I)‐cyclamate against M. tuberculosis.
Synthesis and Molluscicidal Activity of New Chromene and Pyrano[2,3‐c]pyrazole Derivatives
Authors: Abdelrazek Fathy M. , Metz Peter , Kataeva Olga , Jäger Anne , El‐Mahrouky Sherif F.
Published: October 2007

The chromene derivative 4 reacts with acetic anhydride, phenylisothiocyanate and ethyl orthoformate to afford the N‐acetyl derivative 6, the chromenopyrimidine 8 and the formimidate 9, respectively. 2‐(1H‐Indol‐3‐ylmethylene)‐malononitrile 10b reacts with 1,3‐cyclohexanedione and dimedone 11a, b to afford the 4(3‐indolyl)‐chromene derivatives 12a, b respectively, and with the pyrazolone derivatives 13a–d to afford the arylidene exchange derivatives 14a–c and the pyranopyrazole derivative 15, respectively. The arylidene derivatives 10a, b react also with indane‐1,3‐dione 16 to afford the arylidene exchange derivatives 18a, b. The molluscicidal activity of the synthesized compounds towards Biomphalaria alexandrina snails, the intermediate host of Schistosoma mansoni, was investigated and most of them showed weak to moderate activity.
Principal component analysis with boundary constraints
Authors: Giordani Paolo , Kiers Henk A. L.
Published: October 2007

Observed data often belong to some specific intervals of values (for instance in case of percentages or proportions) or are higher (lower) than pre‐specified values (for instance, chemical concentrations are higher than zero). The use of classical principal component analysis (PCA) may lead to extract components such that the reconstructed data take unfeasible values. In order to cope with this problem, a constrained generalization of PCA is proposed. The new technique, called bounded principal component analysis (B‐PCA), detects components such that the reconstructed data are constrained to belong to some pre‐specified bounds. This is done by implementing a row‐wise alternating least squares (ALS) algorithm, which exploits the potentialities of the least squares with inequality (LSI) algorithm. The results of a simulation study and two applications to bounded data are discussed for evaluating how the method and the algorithm for solving it work in practice. Copyright © 2007 John Wiley & Sons, Ltd.
Selective Catalytic Oxidation of Ethanol to Acetic Acid on Dispersed Mo‐V‐Nb Mixed Oxides
Authors: Li Xuebing , Iglesia Enrique
Published: October 2007

The direct oxidation of ethanol to acetic acid is catalyzed by multicomponent metal oxides (Mo‐V‐NbOx) prepared by precipitation in the presence of colloidal TiO2 (Mo0.61V0.31Nb0.08Ox/TiO2). Acetic acid synthesis rates and selectivities (∼95 % even at 100 % ethanol conversion) were much higher than in previous reports. The presence of TiO2 during synthesis led to more highly active surface areas without detectable changes in the reactivity or selectivity of exposed active oxide surfaces. Ethanol oxidation proceeds via acetaldehyde intermediates that are converted to acetic acid. Water increases acetic acid selectivity by inhibiting acetaldehyde synthesis more strongly than its oxidation to acetic acid, thus minimizing prevalent acetaldehyde concentrations and its intervening conversion to COx. Kinetic and isotopic effects indicate that CH bond activation in chemisorbed ethoxide species limits acetaldehyde synthesis rates and overall rates of ethanol conversion to acetic acid. The VOx component in Mo‐V‐Nb is responsible for the high reactivity of these materials. Mo and Nb oxide components increase the accessibility and reducibility of VOx domains, while concurrently decreasing the number of unselective V‐O‐Ti linkages in VOx domains dispersed on TiO2.
Application of Zinc(II)–Binol for the Formal Aza‐Diels–Alder Reaction of N‐Arylimines with Danishefsky's Diene: CD‐Based Absolute Stereochemistry Determination, Origin of Asymmetric Induction and Mechanistic Considerations
Authors: Di Bari Lorenzo , Guillarme Stéphane , Hanan John , Henderson Andrew P. , Howard Judith A. K. , Pescitelli Gennaro , Probert Michael R. , Salvadori Piero , Whiting Andrew
Published: October 2007

Zinc(II)–binol has been employed as an efficient Lewis acid catalyst (10 or 100 mol‐% loading) for the formal aza‐Diels–Alder reaction of ester, furyl and dimethyl acetal‐substituted N‐aryl imines. Asymmetric induction varies from poor to good, with the major enantiomer obtained being (S) when the (S)‐binol complex has been employed. The absolute stereochemistry of the dimethyl acetal‐substituted cycloaduct was determined by CD, and both efficient aza‐Diels–Alder reaction and asymmetric induction are proposed to be dependent upon the formation of bidentate zinc‐imine complexes. These complexes have been modelled using semi‐empirical methods. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Turbulent mixing in spherical implosions
Authors: Youngs David L. , Williams Robin J. R.
Published: October 2007

We discuss the application of the numerical code TURMOIL to turbulent mixing in a simple spherical implosion, a much simplified version of an inertial confinement fusion implosion. Some form of Monotone integrated large eddy simulation is required to eliminate non‐physical oscillations, as shocks and contact discontinuities are present. The dissipation in the TURMOIL scheme is analysed. It is argued that this is relatively low and that the ‘sub‐grid’ dissipation can be precisely quantified. © British Crown Copyright 2007/MOD. Reproduced with permission. Published by John Wiley & Sons, Ltd.
An accurate finite element scheme with moving meshes for computing 3D‐axisymmetric interface flows
Authors: Ganesan Sashikumaar , Tobiska Lutz
Published: October 2007

An accurate finite element scheme for computing 3D‐axisymmetric incompressible free surface and interface flows is proposed. It is based on the arbitrary Lagrangian Eulerian (ALE) approach using free surface/interface‐resolved moving meshes. Key features like the surface force, consisting of surface tension and the local curvature, and jumps in the density and viscosity over different fluid phases are precisely incorporated in the finite element formulation. The local curvature is approximated by using the Laplace–Beltrami operator technique combined with a boundary approximation by isoparametric finite elements. A new approach is used to derive the 3D‐axisymmetric form from the variational form in 3D‐Cartesian coordinates. Several test examples show the high accuracy and the robustness of the proposed scheme. Copyright © 2007 John Wiley & Sons, Ltd.
Projections of the costs associated with colorectal cancer care in the United States, 2000–2020
Authors: Yabroff K. Robin , Mariotto Angela B. , Feuer Eric , Brown Martin L.
Published: October 2007

Because of aging trends in the US, the number of prevalent colorectal cancer patients is expected to increase. We projected economic burden to the Medicare program and its beneficiaries through the year 2020. Burden was estimated for the initial phase of care, the period following diagnosis, the last year of life, and the continuing phase. Projected burden was evaluated with varying assumptions about incidence, survival, and costs of care. Estimated costs of care in 2000 in the initial, continuing, and last year of life phases of care were approximately $3.18 billion, $1.68 billion, and $2.63 billion, respectively. By the year 2020 under the ‘fixed’ current incidence, survival, and cost scenario, projected costs for the initial, continuing, and last year of life phases were $4.75 billion, $2.63 billion, and $4.05 billion. Under the current trends scenario (decreasing incidence, improving survival, and increasing costs), costs were $5.19 billion, $3.57 billion, and $5.27 billion. By the year 2020, estimated costs of colorectal cancer care among individuals aged 65 and older increased by 53% in the fixed scenario and by 89% in the current trends scenario. The future economic burden of colorectal cancer to the Medicare program and its beneficiaries in the US will be substantial. Published in 2007 by John Wiley & Sons, Ltd.
The interactive effects of temperament and maternal parenting on toddlers' externalizing behaviours
Authors: van Aken C. , Junger M. , Verhoeven M. , van Aken M. A. G. , Deković M.
Published: October 2007

The present study aimed to determine the potential moderating effects of temperamental traits on the relation between parenting and toddlers' externalizing behaviours. For that purpose, this study examined the interplay between temperament and maternal parenting behaviours in predicting the level as well as the development of toddlers' externalizing behaviours. Participants were 115 boys (wave 1, M=16.9 months; wave 2, M=23.2 months) and their mothers, who were observed in a 13‐min structured play session at home. With regard to the prediction of the level of externalizing behaviours at wave 1, main effects were found for children's temperamental characteristics. In addition, maternal negative control interacted significantly with children's inhibitory control in predicting this level of externalizing behaviours. The findings with regard to the development of externalizing behaviours showed that the effects of maternal negative control and lack of maternal sensitivity were stronger for toddlers with a difficult temperament: maternal negative control and lack of maternal sensitivity were related to an increase in externalizing behaviours for temperamentally difficult children only. These results offer support for the goodness‐of‐fit hypothesis, stressing the idea that the effects of temperament and the social environment depend to a large extent on their interplay. Copyright © 2007 John Wiley & Sons, Ltd.
Endothelial cytoprotection from oxidized LDL by some crude melanesian plant extracts is not related to their antioxidant capacity
Authors: Owen Patrick L. , Matainaho Teatulohi , Sirois Martin , Johns Timothy
Published: October 2007

Habitual consumption of some Melanesian medicinal and food plants may influence atherosclerosis development via their antioxidant capacity at the endothelial level. Areca nut (AN; Areca catechu), piper inflorescence (PBI; Piper betle), betel quid (BQ), guava buds (GB; Psidium guajava), the leaves (NL), juice (NJ), fruit (NF), and root (NR) of noni (Morinda citrifolia), the propagules of raw (MBR), and cooked (MBC) mangrove (Bruguiera gymnorrhiza) were evaluated for their ability to scavenge the 1,1‐diphenyl‐2‐picryl‐hydrazyle (DPPH) radical, to protect human low‐density lipoprotein (LDL) from Cu2+‐catalyzed oxidation and to protect cultured bovine aortal endothelial cells (BAEC) from oxidized LDL (oxLDL)‐induced cytotoxicity. Polyphenol‐rich extracts AN, PBI, and BQ were potent DPPH scavengers, having similar activity to quercetin and able to protect LDL from oxidation in a dose‐dependent manner at concentrations higher than 10 μg/mL, but were pro‐oxidants at lower concentrations. These extracts were cytotoxic to BAEC at concentrations above 10 μg/mL and were unable to prevent oxLDL endotheliopathy. GB and NR at 10 μg/mL displayed both the ability to delay LDL oxidation and prevent oxLDL cytotoxicity, although the latter lacked the ability to scavenge the DPPH radical. At higher concentrations, however, both were cytotoxic in themselves. The remaining noni extracts NF, NJ, NL, and both mangrove extracts MBC and MBR were unable to protect LDL from oxidation at all tested concentrations, but were effective cytoprotective agents at 50 μg/mL. All extracts were able to prevent an oxLDL‐mediated increase in intracellular aldehyde generation but had little effect on extracellular peroxidation as measured by thiobarbituric acid reactive substances (TBARS). On the basis of this model system, we conclude that the antioxidant benefits of AN, PBI, and BQ may be offset by their enhancement of their cytotoxic effects of oxLDL toward BAEC, whereas GB and low concentrations of noni and mangrove may be considered antiatherogenic. The discrepancies between our in vitro and cellular culture experiments emphasize the importance of experimental conditions in evaluating the antioxidant potential of crude plant extracts. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:231–242, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20186
Cigarette smoke extract affects functional activity of MRP1 in bronchial epithelial cells
Authors: van der Deen Margaretha , de Vries Elisabeth G. E. , Visserman Hylke , Zandbergen Wouter , Postma Dirkje S. , Timens Wim , Timmer‐Bosscha Hetty
Published: October 2007

Cigarette smoke is the principal risk factor for development of chronic obstructive pulmonary disease (COPD). Multidrug resistance‐associated protein 1 (MRP1) is a member of the ATP‐binding cassette (ABC) superfamily of transporters, which transport physiologic and toxic substrates across cell membranes. MRP1 is highly expressed in lung epithelium. This study aims to analyze the effect of cigarette smoke extract (CSE) on MRP1 activity. In the human bronchial epithelial cell line 16HBE14o−, MRP1 function was studied flow cytometrically by cellular retention of carboxyfluorescein (CF) after CSE incubation and MRP1 downregulation by RNA interference (siRNA). Cell survival was measured by the MTT assay. Immunocytochemically, it was shown that 16HBE14o− expressed MRP1 and breast cancer resistance protein. Coincubation of CSE IC50 (1.53% ± 0.22%) with MK571 further decreased cell survival 31% (p, = 0.018). CSE increased cellular CF retention dose dependently from 1.7‐fold at 5% CSE to 10.3‐fold at 40% CSE (both p < 0.05). siRNA reduced MRP1 RNA expression with 49% and increased CF accumulation 67% versus control transfected cells. CSE exposure further increased CF retention 24% (p = 0.031). A linear positive relation between MRP1 function and CSE‐modulating effects (r = 0.99, p =0.089) was shown in untransfected, control transfected, and MRP1 downregulated 16HBE14o− cells analogous to blocking effects with MRP1 inhibitor MK571 (r = 0.99, p = 0.034). In conclusion, cigarette smoke extract affects MRP1 activity probably competitively in bronchial epithelial cells. Inhibition of MRP1 in turn results in higher CSE toxicity. We propose that MRP1 may be a protective protein for COPD development. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:243–251, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20187
Transcriptional responses of alpha‐ and rho‐class glutathione S‐transferase genes in the liver of three freshwater fishes intraperitoneally injected with microcystin‐LR: Relationship of inducible expression and tolerance
Authors: Liang Xu‐Fang , Li Guan‐Gui , He Shan , Huang Yan
Published: October 2007

Rho‐class glutathione S‐transferase (GST) is found only in teleost fish with no homologues in mammals. Silver carp (Hypophthalmichthys molitrix), grass carp (Ctenopharyngodon idellus), and Nile tilapia (Oreochromis nilotica) are three warm freshwater fishes with differential tolerance to microcystin‐LR (MC‐LR): Nile tilapia has a little higher tolerance than silver carp, but both have much higher tolerance than grass carp. Full‐length cDNAs encoding the rho‐class GST were cloned and sequenced from the livers of the three fishes. The silver carp, grass carp, and Nile tilapia rho‐class GST cDNAs were 1078, 1104, and 904 bp in length, respectively, and all contained an open‐reading frame (ORF) of 681 bp (encoding a polypeptide of 226 amino acids). Using beta‐actin as an external control, semiquantitative RT‐PCR was conducted to determine the constitutive and inducible expression level of alpha‐ and rho‐class GST genes among the three fishes (6–12 g) intraperitoneally injected with MC‐LR (50 μg kg−1 body weight). Liver mRNA expression levels of alpha‐class GST gene were found to be higher than those of rho‐class GST gene in both exposed and control fish of silver carp and grass carp, whereas liver mRNA expression levels of rho‐class GST gene were higher than those of alpha ‐class GST gene in both exposed and control fish of Nile tilapia. Increased liver transcription of GST isoforms was detected at 8‐h postinjection of MC‐LR in silver carp (alpha‐ and rho‐class GST) and Nile tilapia (rho‐class GST), and at 24‐h postinjection in silver carp (alpha‐class GST) and Nile tilapia (alpha‐class GST), but an increase in liver transcription neither of alpha‐class GST nor of rho‐class GST was detected in grass carp at either 8‐h or 24‐h postinjection. The inducible expression of the liver GST gene showed a close relationship with their tolerance to MC‐LR: high‐resistant fish (phytoplanktivorous silver carp and Nile tilapia) had inducible liver expression of either alpha‐ or rho‐class GST, and the high‐sensitive fish (herbivorous grass carp) had no inducible liver expression of either one. We suggest that inducible expression (instead of constitutive expression) of the liver GST gene should play an important role in the tolerance to microcystin exposure, and that in addition to alpha‐class GST, high‐liver expression of rho‐class GST gene might have facilitated the evolutionary radiation of teleost fish. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:289–298, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20188
Dimethylsphingosine and FTY720 inhibit the SK1 form but activate the SK2 form of sphingosine kinase from rat heart
Authors: Vessey Donald A. , Kelley Michael , Zhang Jianqing , Li Luyi , Tao Rong , Karliner Joel S.
Published: October 2007

Fractionation of cytosolic sphingosine kinase (SKase) activity by gel filtration chromatography gave rise to a 96‐kDa peak that contained only the SK2 form of SKase (by Western analysis) and a broad ca. 46 kDa peak that contained only SK1 forms. SK2 appeared to have a bound accessory protein. When tested with the classic SKase inhibitor dimethylsphingosine (DMS), SK1 was extensively inhibited; however, SK2 was not inhibited but unexpectedly was activated. Activation of SK2 was the result of DMS enhancing the affinity of the enzyme for sphingosine, and, at low concentrations of ATP and sphingosine, activated by more than 100%. Activation of SK2 could be demonstrated in the cytosolic fraction indicating it was unrelated to the purification step. The immunomodulator FTY720 also activated SK2 (although to a lesser extent), but was a potent inhibitor of SK1. SK2 from rat liver and spleen was also not inhibited by DMS. L‐Sphingosine and to a lesser extent dihydrosphingosine and phytosphingosine were effective inhibitors of both forms.© 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:273–279, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20193
Modulation of indomethacin‐induced gastric injury by spermine and taurine in rats
Authors: Motawi Tarek K. , Abd Elgawad Hanan M. , Shahin Nancy N.
Published: October 2007

This study investigated the involvement of neutrophil infiltration, nitric oxide (NO) generation, and oxidative stress in indomethacin‐induced ulcer and the possible gastroprotective potentials of spermine and taurine, known for their tissue regenerating and antioxidant effects, respectively. Male Wistar albino rats (180–220 g) were allocated into a normal control group, ulcer control group (received a single dose of indomethacin 40 mg–kg p.o.), and two ulcer groups pretreated with spermine (150 mg–kg p.o. 1 h before ulcer induction) and taurine (250 mg–kg i.p. for three consecutive days before ulcer induction). The animals were killed 6 h after indomethacin administration, and the gastric juice, serum, and mucosal tissue were used for gastric injury evaluation. Both modulators significantly ameliorated the indomethacin–induced gastric lesions in glandular mucosa. Notably, spermine exhibited the most pronounced effect as manifested by great reduction in the gastric ulcer index, normalization of the elevated gastric acidity, and triggering of mucin production. Spermine and taurine were able to decrease the elevated levels of gastric myeloperoxidase, conjugated diene, and serum NO. However, the lowered tissue NO content was markedly elevated only by taurine. The antioxidant action of taurine was illustrated by restoration of the depressed content of glutathione, normalization of the inhibited activities of glutathione reductase, and superoxide dismutase. These results suggest that spermine and taurine confer significant gastroprotection against indomethacin‐induced gastric injury with the priority of spermine. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:280–288, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20194
The unwary purchaser: Consumer psychology and the regulation of commerce in America
Authors: Pettit Michael J.
Published: October 2007

Starting in the 1870s, American jurists deciding cases of trademark infringement began advancing arguments that the ordinary purchaser was an unwary one, easily deceived by imitations. Embedded within their legal decisions was a vision of the typical consumers' habitual behavior and cognitive ability. In response to legal critics who argued that the presumed psychology of the consumer was unevenly deployed, applied psychologists developed laboratory‐based experiments and scales for determining the likelihood that the “average” purchaser would be confused. Although these psychologists failed in their goal of securing regular legal patronage, this commercial context and the resulting experiments were constitutive of the delineation of “recognition” as a distinct mental process. Furthermore, this case study complicates the scholarly consensus about the role of standardization and personal responsibility in the liberal administration of mass society. © 2007 Wiley Periodicals, Inc.
Alpha‐amylase production by Bacillus subtilis CM3 in solid state fermentation using cassava fibrous residue
Authors: Swain M.R. , Ray R.C.
Published: October 2007

In extraction of starch from cassava (Manihot esculenta Crantz), one of the major solid waste released is fibrous residues which constitute 15–20% by weight of the cassava chips/tuber processed. Production of α ‐amylase under solid state fermentation by Bacillus subtilis CM3 has been investigated using cassava fibrous residue. Response surface methodology (RSM) was used to evaluate the effect of the main variables, i.e. incubation period, initial medium pH, moisture holding capacity and temperature on enzyme production. A full factorial Central Composite Design (CCD) was applied to study these main factors that affected α ‐amylase production. The experimental results showed that the optimum incubation period, initial medium pH, moisture holding capacity and temperature were 6 days, 8.0, 70% and 50 °C, respectively. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Determination of cadmium and selected micronutrients in commonly used and traded medicinal plants in Turkey
Authors: Sekeroglu Nazim , Ozkutlu Faruk , Kara S Metin , Ozguven Mensure
Published: October 2007

BACKGROUND: Medicinal plants commonly used and traded in Turkey were monitored for their cadmium and selected micronutrient (copper, iron, manganese and zinc) content.

RESULTS: Cadmium was not detected in any sample of licorice extract, linden flowers or nettle leaves. However, in the rest of the samples, cadmium was found in the range of 7–126 µg kg−1, with the highest concentration in chamomile leaf. Of all the monitored trace elements, the highest concentration found was 520 mg kg−1 iron in zahter. The highest copper, manganese and zinc concentrations were found in rose hips (24 mg kg−1), Turkish oregano (58 mg kg−1) and zahter (50 mg kg−1), respectively.

CONCLUSION: The results of the present study reveal that cadmium and trace element concentrations in medicinal plants commonly used as traditional medicines in Turkey are well below the critical levels. Copyright © 2007 Society of Chemical Industry
Preparation and Biodegradation of Sugar‐Containing Poly(vinyl acetate) Emulsions
Authors: Takasu Akinori , Baba Michiko , Hirabayashi Tadamichi
Published: October 2007

To accelerate the biodegradability of poly(vinyl acetate)‐based emulsions, emulsion copolymerizations of vinyl sugars, including triacetylated N‐acetyl‐D‐glucosamine (GlcNAc)‐substituted 2‐hydroxyethyl methacrylate (GlcNAc(Ac)3‐substituted HEMA), glucose‐substituted HEMA (GEMA) and 6‐O‐vinyladipoyl‐D‐glucose (6‐O‐VAG) with vinyl acetate (VAc), were carried out using poly(vinyl alcohol) as an emulsifying agent in the presence of poly[(butylene succinate)‐co‐(butylene adipate)] [poly(BS‐co‐BA)]. Copolymerization with GEMA produced a stable emulsion and that with 6‐O‐VAG also produced a homogeneous emulsion. Their biodegradation tests indicated that PVAc main chain scission was accelerated by copolymerization with vinyl sugars.

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Electrospun Chitosan‐Coated Fibers of Poly(L‐lactide) and Poly(L‐lactide)/Poly(ethylene glycol): Preparation and Characterization
Authors: Spasova Maria , Paneva Dilyana , Manolova Nevena , Radenkov Philip , Rashkov Iliya
Published: October 2007

Fibrous poly(L‐lactide) (PLLA) and bicomponent PLLA/poly(ethylene glycol) mats were prepared by electrospinning and then were coated with chitosan. The presence of chitosan coating was proved by scanning electron microscopy and by fluorescence microscopy. On contact with blood, the chitosan coating led to changes in erythrocyte shape and in their aggregation. The haemostatic activity of the mats increased with increasing chitosan content. Microbiological studies against Staphylococcus aureus revealed that the chitosan coating imparts antibacterial activity to the hybrid mats. The combined haemostatic and antibacterial activities render these novel materials suitable for wound‐healing applications.

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Rheological Response of Polyethylene/Clay Nanocomposites to Annealing Treatment
Authors: Botta Luigi , La Mantia Francesco Paolo , Dintcheva Nadka Tzankova , Scaffaro Roberto
Published: October 2007

The rheological response of a polyethylene/clay nanocomposite to annealing treatment under air and nitrogen atmospheres was studied. The treatment influences the rheology of the nanocomposite significantly. In particular, the viscosity and the non‐Newtonian behavior dramatically increase with annealing time, and a liquid‐like/solid‐like transition is observed. The annealed samples were characterized by ATR‐FT‐IR spectrometry and it was shown that a silicate‐rich layer is formed on the surface of the nanocomposite. This result was confirmed by TEM images of bulk and surface of annealed samples. It was demonstrated that the formation of this coating is the main cause of the change of rheological behavior.

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Effect of Arrangement of L‐Lactide and D‐Lactide in Poly[(L‐lactide)‐co‐(D‐lactide)] on its Resistance to Hydrolysis Studied by Molecular Modeling
Authors: Karst David , Yang Yiqi
Published: October 2007

Molecular modeling is used to explain how the resistance of poly[(L‐lactide)‐co‐(D‐lactide)] to hydrolysis is affected by the percentages of L‐ and D‐lactide and their arrangements in blocks or random arrangements in the polymer. Previous studies on improving the hydrolysis resistance of PLA have involved forming either poly(L‐lactide)/poly(D‐lactide) (PLLA/PDLA) polyblends or copolymers of L‐ and D‐lactide. In this study, molecular modeling was used to study the hydrolysis resistance of PLA containing various arrangements of L‐ and D‐lactide in the polymers. PLA copolymers are found to have less resistance to hydrolysis than a PLLA/PDLA polyblend having the same percentages of L‐ and D‐lactide because a polyblend can form more stereocomplexes, which is the most stable structure PLA can form.

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Preparation and Fluorescent and Magnetic Properties of Polyurethane/Eu(MA)3 Films
Authors: Zhou Shuxue , Yin Yijing , You Bo , Wu Limin , Chen Min
Published: October 2007

Europium(III) (Eu3+)‐doped polyurethane films were prepared by mixing Eu‐methacrylic acid complex (Eu(MA)3) with aliphatic polyurethane oligomer and subsequently curing under UV irradiation. Transmission electron microscopy photos and the appearance of the resulting hybrid films showed that phase separation occurred only at an Eu(MA)3 content above 20 wt.‐%. Fluorescence spectra indicated that the fluorescence of Eu3+ was barely influenced by the polyurethane matrix and its intensity increased with an Eu(MA)3 content in the range of approximately 0 to 10 wt.‐%. An obvious applied external‐field‐dependent magnetization (M) of polyurethane/Eu(MA)3 films, namely, an increasing M at low field and a decreasing M at high field, was observed at room temperature from the hysteresis loops, which was influenced by both the Eu(MA)3 content and the ultrasonication imposed on the coatings before curing. It seems that ultrasonication leads to a thermodynamically‐unstable structure of Eu3+ in hybrid films, which can be fixed by UV curing but gradually rearranges to its original form during the thermal‐curing process, and enhances the diamagnetic part of the hybrid film. Thus, the magnetic property of Eu3+‐doped polyurethane film at room temperature can be adjusted by simply changing the preparation method and the Eu(MA)3 content instead of the type of Eu3+‐organic complex.

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How can Nanohybrids Enhance Polyester/Sepiolite Nanocomposite Properties?
Authors: Duquesne Emmanuel , Moins Sébastien , Alexandre Michaël , Dubois Philippe
Published: October 2007

PCL/sepiolite (nano)composites are prepared by melt blending in a twin‐screw mini‐extruder, and PCL/sepiolite nanohybrids are synthesized by ROP of ε‐CL. The nanohybrids have been used as masterbatches and dispersed in a commercial PCL matrix. Composites with 3 wt.‐% nanofiller were prepared and characterized thermally, mechanically, and morphologically. Sepiolite addition has a profound effect on the mechanical properties of the PCL/sepiolite nanocomposites. Sepiolite disperses well in PCL, which leads to a significant increase in Young's modulus. The use of a PCL nanohybrid as masterbatch further improves the stiffness but also the toughness of the material in the elastic range.

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Effect of the Penultimate Unit on the CON Bond Homolysis in SG1‐Based Alkoxyamines
Authors: Bertin Denis , Dufils Pierre‐Emmanuel , Durand Isabelle , Gigmes Didier , Giovanetti Bruno , Guillaneuf Yohann , Marque Sylvain R. A. , Phan Trang , Tordo Paul
Published: October 2007

The effect of the penultimate unit on the CON bond homolysis rate constant kd was studied for model alkoxyamines. It was shown that the kd for fragments containing penultimate and antepenultimate units were nicely predicted by the tri‐parametric relationship developed in Macromolecules 2005, 38, 2638 and Eur. J. Org. Chem. 2006, 7, 1755 (log kd = −14.33 + 15.06 × σRS + 20.00 × σI + 6.96 × υ). A striking effect was observed only for a tert‐butyl‐like group as the penultimate unit.

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Interpenetrating Thermo and pH Stimuli‐Responsive Polymer Networks of PAAc/PNIPAAm Grafted onto PP
Authors: Ruiz Juan‐Carlos , Burillo Guillermina , Bucio Emilio
Published: October 2007

A new strategy was used to prepare an interpenetrating polymer network of two stimuli‐responsive polymers, a thermosensitive poly N‐isopropylacrylamide (PNIPAAm) and a pH sensitive poly(acrylic acid) (PAAc) grafted onto poly(propylene) (PP) films (PP‐g‐PAAc). Three consecutive steps were used: graft copolymerization of PAAc onto PP films by gamma radiation, crosslinking of PP‐g‐PAAc to form the first network, and synthesis of a second network of PNIPAAm in situ within the crosslinked PP‐g‐PAAc by chemical polymerization and crosslinking. The phase transition temperature (LCST), measured by swelling measurements and DSC, the pH critical point, obtained by swelling, and the SEM derived morphology of network samples are reported.

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Process Engineering for Production of Chiral Hydroxycarboxylic Acids from Bacterial Polyhydroxyalkanoates
Authors: Ren Qun , Ruth Katinka , Thöny‐Meyer Linda , Zinn Manfred
Published: October 2007

An efficient process for the production of (R)‐hydroxycarboxylic acids (RHAs) from polyhydroxyalkanoates (PHAs) was developed. It involved the synthesis of PHA in bacteria, followed by bringing the culture broth directly to a pH optimal for in vivo PHA degradation, thus avoiding cell collection by centrifugation and pellet resuspension. The optimal pH was maintained to allow maximal release of RHAs. Using this process, cells having a dry weight (w) of 1.8 g · L−1 and 45% (w/w) PHA exhibited a linear PHA degradation rate of about 0.059 g · L−1 · h−1 in the first 9 h. Concomitantly, RHAs were released with a rate of 0.057 g · L−1 · h−1. Further incubation of up to 15 h resulted in almost 90% (w/w) degradation of PHA. Based on this approach in combination with chemostat and a plug flow reactor a continuous process for the production of RHAs could be achieved.

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Suppression of Crazing in Polystyrene Crosslinked with a Multifunctional Zirconium Oxo Cluster Observed In Situ during Tensile Tests
Authors: Puchegger Stephan , Rennhofer Harald , Kogler Franz Rene , Loidl Dieter , Bernstorff Sigrid , Schubert Ulrich , Peterlik Herwig
Published: October 2007

The structural development of polystyrene, which was crosslinked with varying amounts of the multifunctional cluster Zr6O4(OH)4(methacrylate)12, was followed in situ by small‐angle X‐ray scattering at a synchrotron radiation source. It was observed that crazing strongly diminishes with increasing cluster proportion and disappears nearly completely for the material with the highest cluster proportion of 0.87 mol‐%. Accordingly, the maximum stress before failure is strongly enhanced, whereas the maximum strain decreases.

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Down syndrome: Cognitive phenotype
Authors: Silverman Wayne
Published: October 2007

Down syndrome is the most prevalent cause of intellectual impairment associated with a genetic anomaly, in this case, trisomy of chromosome 21. It affects both physical and cognitive development and produces a characteristic phenotype, although affected individuals vary considerably with respect to severity of specific impairments. Studies focusing on the cognitive characteristics of Down syndrome were reviewed, and while performance in most areas could be predicted based upon overall intellectual disability, relative weaknesses were consistently found to be associated with expressive language, syntactic/morphosyntactic processing, and verbal working memory. This profile of uneven deficits could result from a failure to develop typically automatic processing for speech perception and production, and this possibility is discussed along with its implications for intervention. © 2007 Wiley‐Liss, Inc. MRDD Research Reviews 2007;13:228–236.
Psychiatric and behavioral disorders in persons with Down syndrome
Authors: Dykens Elisabeth M.
Published: October 2007

Similar to the state of the broader intellectual disabilities field, many gaps exist in the research and treatment of mental health concerns in people with Down syndrome. This review summarizes key findings on the type and prevalence of behavior and emotional problems in children, adolescents, and adults with Down syndrome. Such findings include relatively low rates of severe problems in children, and well‐documented risks of depression and Alzheimer's disease in older adults. The review also considers emerging data on autism, and the paucity of studies on adolescents. Three next steps for research are highlighted, including a need to: (1) connect research on psychiatric status and diagnoses across developmental periods, including adolescence, and to examine such associated processes as sociability, anxiety and attention; (2) unravel complicated biopsycho‐social risk and protective factors that serve to increase or diminish psychopathology; and (3) identify evidence‐based treatments that both reduce distressful symptoms and enhance well‐being in individuals with Down syndrome. © 2007 Wiley‐Liss, Inc. MRDD Research Reviews 2007;13:272–278.
Genetic mechanisms involved in the phenotype of Down syndrome
Authors: Patterson David
Published: October 2007

Down syndrome (DS) is the most common genetic cause of significant intellectual disability in the human population, occurring in roughly 1 in 700 live births. The ultimate cause of DS is trisomy of all or part of the set of genes located on chromosome 21. How this trisomy leads to the phenotype of DS is unclear. The completion of the DNA sequencing and annotation of the long arm of chromosome 21 was a critical step towards understanding the genetics of the phenotype. However, annotation of the chromosome continues and the functions of many genes on chromosome 21 remain uncertain. Recent findings about the structure of the human genome and of chromosome 21, in particular, and studies on mechanisms of gene regulation indicate that various genetic mechanisms may be contributors to the phenotype of DS and to the variability of the phenotype. These include variability of gene expression, the activity of transcription factors both encoded on chromosome 21 and encoded elsewhere in the genome, copy number polymorphisms, the function of conserved nongenic regions, microRNA activities, RNA editing, and perhaps DNA methylation. In this manuscript, we describe current knowledge about these genetic complexities and their likely importance in the context of DS. We identify gaps in current knowledge and suggest priorities to fill these gaps. © 2007 Wiley‐Liss, Inc. MRDD Research Reviews 2007;13:199–206.