bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

AbstractBACKGROUND: 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

AbstractTo 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.magnified image
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

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

AbstractThe 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.magnified image
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

AbstractMolecular 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.magnified image
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

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

AbstractPCL/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.magnified image
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

AbstractThe 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.magnified image
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

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

AbstractAn 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.magnified image
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

AbstractThe 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.magnified image
Down syndrome: Cognitive phenotype
Authors: Silverman Wayne 
Published: October 2007

AbstractDown 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

AbstractSimilar 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

AbstractDown 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.
Using mouse models to explore genotype–phenotype relationship in Down syndrome
Authors: Salehi Ahmad , Faizi Mehrdad , Belichenko Pavel V. , Mobley William C. 
Published: October 2007

AbstractDown Syndrome (DS) caused by trisomy 21 is characterized by a variety of phenotypes and involves multiple organs. Sequencing of human chromosome 21 (HSA21) and subsequently of its orthologues on mouse chromosome 16 have created an unprecedented opportunity to explore the complex relationship between various DS phenotypes and the extra copy of ∼300 genes on HSA21. Advances in genetics together with the ability to generate genetically well‐defined mouse models have been instrumental in understanding the relationships between genotype and phenotype in DS. Indeed, elucidation of these relationships will play an important role in understanding the pathophysiological basis of this disorder and helping to develop therapeutic interventions. A successful example of using such a strategy is our recent studies exploring the relationship between failed nerve growth factor (NGF) transport and amyloid precursor protein (App) overexpression. We found that increased dosage of the gene for App is linked to failed NGF signaling and cholinergic neurodegeneration in a mouse model of DS. Herein, we discuss several mouse models of DS and explore the emergence of exciting new insights into genotype–phenotype relationships, particularly those related to nervous system abnormalities. An important conclusion is that uncovering these relationships is enhanced by working from carefully defined phenotypes to the genes responsible. © 2007 Wiley‐Liss, Inc. MRDD Research Reviews 2007;13:207–214.
Organoaluminum‐mediated polymerization of diazoketones
Authors: Ihara Eiji , Kida Masami , Itoh Tomomichi , Inoue Kenzo 
Published: October 2007

AbstractPolymerization of diazoketones mediated by organoaluminum compounds was investigated. Trialkylaluminum R3Al (R = iBu, Et, Me) and diisobutylaluminum hydride (DIBAL) polymerized (E)‐1‐diazo‐3‐nonen‐2‐one (1) to give polymers with Mn = 2000–3500, which contained nearly 33 mol % of azo group (NN) along with the dominant acylmethylene unit in the main chain. On the other hand, when (E)‐1‐diazo‐4‐phenyl‐3‐buten‐2‐one (2) was used as a monomer for the organoaluminum‐mediated polymerization, the resulting polymers had ethylidene (CH[CH3]) units in the main chain along with acylmethylene and azo group, as a result of reductive cleavage of the acyl group during the polymerization. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5209–5214, 2007
Developing a hybrid emulsion polymerization system to synthesize Fe3O4/polystyrene latexes with narrow size distribution and high magnetite content
Authors: Cui Longlan , Xu Hong , He Ping , Sumitomo Keiko , Yamaguchi Yoshinori , Gu Hongchen 
Published: October 2007

AbstractA hybrid emulsion polymerization was formulated for synthesizing Fe3O4/polystyrene composite latex. This system, containing binary droplets that are magnetic (Mag)‐droplets with a diameter of 100–200 nm and styrene (St)‐droplets with a diameter of 3–4 μm, was obtained by mixing Mag‐miniemulsion and St‐macroemulsion. With extremely low surfactants concentration (≪critical micelle concentration, CMC), the nucleated loci are selectively controlled in the Mag‐droplets, as the result of smaller droplet size and larger surface ratio. Both water‐soluble potassium persulfate (KPS) and oil‐soluble 2,2′‐azobis(2‐isobutyronitrile) was adopted to initiate the polymerization. In the presence of KPS, magnetic polystyrene latices with particles size of 60–200 nm, narrow size distribution, and high magnetite content (86 wt % measured by TGA) were attained successfully. The synthesized magnetic Fe3O4/polystyrene latices assembled into well‐ordered hexagonal structure in the surface of a carbon supported copper grid. The influence of various parameters on various aspects of the as‐synthesized Fe3O4/polystyrene was investigated in detail: type of initiator on composite morphology, feed ratio of Mag‐miniemulsion and St‐macroemulsion on magnetite content, and hydrophobic agent or amount of surfactant on size and size distribution. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5285–5295, 2007
Quantification of allele E198A in beta‐tubulin conferring benzimidazole resistance in Monilinia fructicola using real‐time PCR
Authors: Luo Yong , Ma Zhonghua , Michailides Themis J 
Published: October 2007

AbstractBACKGROUND: Thiophanate‐methyl, a member of the benzimidazole class of fungicides, is used in California to control brown rot of stone fruit caused by Monilinia fructicola (G. Wint.) Honey. The goal of this study was to develop a real‐time polymerase chain reaction (PCR) assay as an efficient method to quantify the E198A allele of β‐tubulin that confers benzimidazole resistance.RESULTS: Using the real‐time PCR assay, the frequency of allele E198A (FEA) in a population was determined from the quantities of DNA amplified with the E198A allele‐specific primer pair HRF/HRR and the M. fructicola—specific primer pair MfF6/MfR6. The average proportions of highly resistant isolates determined with the conventional fungicide sensitivity method were within the range of average FEA values determined with the real‐time PCR assay. We also determined the FEAs of M. fructicola populations sampled from 21 stone fruit orchards in California. Only one orchard showed a high FEA over 0.20, seven orchards had values between 0.01 and 0.1, and 13 orchards had values less than 0.01.CONCLUSION: The real‐time PCR assay developed in this study provides a potentially useful tool to efficiently quantify benzimidazole resistance for large M. fructicola populations. Copyright © 2007 Society of Chemical Industry
Strobilurin fungicides induce changes in photosynthetic gas exchange that do not improve water use efficiency of plants grown under conditions of water stress
Authors: Nason Mark A , Farrar John , Bartlett David 
Published: October 2007

AbstractThe effects of five strobilurin (beta‐methoxyacrylate) fungicides and one triazole fungicide on the physiological parameters of well‐watered or water‐stressed wheat (Triticum aestivum L.), barley (Hordeum vulgare L.) and soya (Glycine max Merr.) plants were compared. Water use efficiency (WUE) (the ratio of rate of transpiration, E, to net rate of photosynthesis, An) of well‐watered wheat plants was improved slightly by strobilurin fungicides, but was reduced in water‐stressed plants, so there is limited scope for using strobilurins to improve the water status of crops grown under conditions of drought. The different strobilurin fungicides had similar effects on plant physiology but differed in persistence and potency. When applied to whole plants using a spray gun, they reduced the conductance of water through the epidermis (stomatal and cuticular transpiration), gsw, of leaves. Concomitantly, leaves of treated plants had a lower rate of transpiration, E, a lower intercellular carbon dioxide concentration, ci, and a lower net rate of photosynthesis, An, compared with leaves of control plants or plants treated with the triazole. The mechanism for the photosynthetic effects is not known, but it is hypothesised that they are caused either by strobilurin fungicides acting directly on ATP production in guard cell mitochondria or by stomata responding to strobilurin‐induced changes in mesophyll photosynthesis. The latter may be important since, for leaves of soya plants, the chlorophyll fluorescence parameter Fv/Fm (an indication of the potential quantum efficiency of PSII photochemistry) was reduced by strobilurin fungicides. It is likely that the response of stomata to strobilurin fungicides is complex, and further research is required to elucidate the different biochemical pathways involved. Copyright © 2007 Society of Chemical Industry
Behaviour of sulcotrione and mesotrione in two soils
Authors: Chaabane Hanène , Vulliet Emmanuelle , Calvayrac Christophe , Coste Camille‐Michel , Cooper Jean‐François 
Published: October 2007

AbstractThe behaviour of sulcotrione, a recently introduced triketone herbicide, in various soil types was studied under laboratory conditions. In particular, degradation and sorption processes were examined on Ghent and Perpignan soils. Kinetics showed that the degradation of sulcotrione was influenced by biotic and/or abiotic factors. Half‐lives ranged between 45 and 65 days. Among the degradation compounds identified were 1,3‐cyclohexanedione (CHD) and 2‐chloro‐4‐mesyl benzoic acid (CMBA), previously described as hydrolysis products, and, under special conditions, a derivative of phenylheptanoic acid (PHD). This new degradation product suggested that sulcotrione could follow two possible pathways in the soil, as in water. During the sorption study, a moderate retention of sulcotrione and CMBA relative to CHD and PHD, which were highly adsorbed whatever the soil type, was reported. Experiments carried out under the same conditions for sulcotrione and mesotrione, another triketone herbicide recommended in maize culture, made it possible to compare the two triketones and to conclude that they exhibited relatively similar behaviour in the soil, i.e. that their leaching potential needs to be properly addressed and risks evaluated. Copyright © 2007 Society of Chemical Industry