bluuebunny/crossref_metadata_2025 huggingface dataset:
Annual Changes of Abundance and Biomass of Planktonic Ciliates in the Gdańsk Basin, Southern Baltic
Authors: Witek Marzena
Published: February 2007

Seasonal changes in the species composition, abundance and biomass of planktonic ciliates were determined every 2–3 weeks at two sites of 30 m depth and one location of 105 m depth in the southwestern Gdańsk Basin between January 1987 and January 1988. A total of 40 ciliate taxa were observed during this period. Autotrophic Mesodinium rubrum dominated ciliate abundance and biomass: maximal values of 50 · 10−1 ind. 1‐1 and 65 μg C 1−1 were recorded. The annual mean biomass of M. rubrum comprised 6 to 9% of the annual mean phytoplankton biomass. The highest abundances and biomasses of heterotrophic ciliates were noted at all stations in the spring and summer in the euphotic zone with maximum values of 28 · 103 ind. 1−1 and 23 μg C 1−1. Three ciliates assemblages were distinguished in the epipelagic layer: large and medium‐size non‐predatory ciliates, achieving peak abundance in spring and autumn; small‐size microphagous ciliates and epibiotic ciliates which were abundant in summer, and large‐size predacious ciliates dominating in spring. Below 60 m, a separate deep‐water ciliate community composed of Prorodon‐like ciliates and Metacystis spp. was found. The ciliate biomass in the 60–105 m layer was similar to the ciliate biomass in the euphotic zone. The heterotrophic ciliate community contributed 10 to 13% to the annual mean zooplankton biomass. The potential annual production of M. rubrum comprised 6 to 9% of the total primary production. Carbon demand of non‐predatory ciliates, calculated on the basis of their potential production, was estimated to be equivalent to 12–15% of the gross primary production.
Rotifera Recorded from China, 1893–1997, with Remarks on Their Composition and Distribution
Authors: Zhuge Yan , Huang Xiangfei , Koste Walter
Published: February 2007

A search of the literature on rotifers recorded from China, includes today 477 valid species names and 42 subspecies or infrasubspecific variants in 84 genera and 28 families recorded since 1893. Chinese rotifera research is reviewed, and all recorded species are listed with current taxonomic status and their first localities in China. Most of the named taxa are widely distributed or cosmopolitan, with only a small number (about 3%) possibly restricted to China. This fauna exhibits 15 endemic taxa. The composition and distribution of Chinese Rotifera are briefly analyzed. It is likely that considerably more rotifers remain to be described from China as further study to be carried on and taxonomic resolution improves.
Suppression of growth and cancer‐induced angiogenesis of aggressive human breast cancer cells (MDA‐MB‐231) on the chorioallantoic membrane of developing chicken embryos by E‐peptide of pro‐IGF‐I
Authors: Chen Maria J. , Peter Chiou Pinwen , Lin Patrick , Lin Chun‐Mean , Siri S. , Peck Konan , Chen Thomas T.
Published: February 2007

E‐peptide of the pro‐Insulin‐like growth factor‐I (pro‐IGF‐I) is produced from pre‐pro‐IGF‐I by proteolytic cleavage in the post‐translational processing. Previous in vitro studies conducted in our laboratory showed that Ea4‐peptide of rainbow trout (rt) pro‐IGF‐I or Eb‐peptide of human (h) pro‐IGF‐I exhibited activities including induction of morphological differentiation, inhibition of anchorage‐independent cell growth and suppression of invasion of several well established human cancer cell lines such as MDA‐MB‐231, HT‐29, SK‐N‐F1, and HepG‐2 (Chen et al. [2002] Gen Comp Endocrinol 126:342–351; Kuo and Chen [2002] Exp Cell Res 280:75–89). Seeding of aggressive human breast cancer cells, MDA‐MB‐231, on the chorioallantoic membrane (CAM) of 5 days old chicken embryos resulted in rapid growth and invasion of the cells and induction of blood vessel formation around the MDA‐MB‐231 cell mass in the chicken embryos. The invasion of MDA‐MB‐231 cells in the chicken embryos was further confirmed by immunocytochemistry. The rapid growth and invasion of MDA‐MB‐231 cells and the induction of blood vessel formation by MDA‐MB‐231 cells on chicken CAM are inhibited by treatment with a single or multiple doses of rtEa4‐ or hEb‐peptide. Furthermore, a dose‐dependent inhibition of angiogenesis by rtEa4‐ or hEb‐peptide was also demonstrated by the chicken CAM assay. Results of microarray analysis of human gene chips (containing 9,500 unique cDNA clones) and confirmation by comparative real‐time RT‐PCR analysis showed that a group of genes related to cancer cell activities are up‐ or down‐regulated in MDA‐MB‐231 cells transfected with a rtEa4‐peptide gene. Together these results confirm the anti‐tumor activity of rtEa4‐ and hEb‐peptides, and further suggest that these peptides could be developed as therapeutics for treating human cancers. J. Cell. Biochem. 101:1316–1327, 2007. © 2007 Wiley‐Liss, Inc.
Dissociation of growth arrest and CYP24 induction by VDR ligands in mammary tumor cells
Authors: Valrance Meggan E. , Brunet Andrea H. , Acosta Anna , Welsh JoEllen
Published: February 2007

Murine mammary tumor cells with differential vitamin D receptor (VDR) expression were used to study the mechanisms of growth inhibition by vitamin D steroids. In VDR‐expressing WT145 cells, 1,25D and its synthetic analog EB1089 induce growth arrest and transcriptionally upregulate the well‐characterized VDR target gene CYP24. 1,25D also induces apoptosis in WT145 cells through activation of initiator and executioner caspases and the calcium‐dependent protease calpain. We also demonstrate that WT145 cells express CYP27B1, the enzyme that converts 25‐hydroxyvitamin D3 (25D) to 1,25D, and that 25D inhibits growth of these cells but does not trigger apoptosis or induce CYP24 expression. Comparative studies were conducted in KO240 cells, which were derived from VDR knockout mice and found to retain expression of CYP27B1. KO240 cells were not growth inhibited nor rendered apoptotic by any of the tested vitamin D compounds. These data conclusively demonstrate that VDR mediates the anti‐proliferative and pro‐apoptotic effects of vitamin D metabolites and analogs, but that the potency of a vitamin D compound to induce the VDR target gene CYP24 does not accurately predict its potency in mediating growth regulation. J. Cell. Biochem. 101: 1505–1519, 2007. © 2007 Wiley‐Liss, Inc.
Supracolloidal Structures through Liquid‐Liquid Interface Driven Assembly and Polymerization
Authors: Colver Patrick J. , Chen Tao , Bon Stefan A. F.
Published: February 2007

Solid particles can adhere to liquid‐liquid interfaces. When emulsion droplets are stabilized in such a way one speaks of a Pickering emulsion. The supracolloidal structures formed by this interface driven assembly process can be referred to as colloidosomes. Herein we explain the concept of colloidosome formation, their deformation behavior upon evaporation of their inner phase. Moreover, we describe Pickering miniemulsion and suspension polymerization processes, both yielding armored raspberry‐type core‐shell composite polymer particles.
Poly(styrene‐co‐butyl acrylate)‐Brazilian Montmorillonite Nanocomposites, Synthesis of Hybrid Latexes via Miniemulsion Polymerization
Authors: Moraes Raul P. , Santos Amilton M. , Oliveira Pedro C. , Souza Fátima C. T. , do Amaral Marcelo , Valera Ticiane S. , Demarquette Nicole R.
Published: February 2007

In this work hybrid latexes of poly(styrene‐co‐butyl acrylate)/montmorillonite were synthesized via miniemulsion polymerization using a Brazilian organically modified montmorillonite. The natural clay was previously treated with Cetyltrimethyl ammonium chloride (CTAC) in order to increase the interaction between the clay and the monomer phase. Three different methodologies to modify the clay and their influence on the final properties of the composites obtained were evaluated in this work. The modified clays were characterized by X‐ray diffraction (XRD). The films obtained after drying the latexes were characterized by dynamic‐mechanical thermal analyses (DMTA), small amplitude oscillatory shear (SAOS), transmission electronic microscopy (TEM) and Cobb test. The X‐ray diffractograms, showed an increase of basal spacing after organic treatment indicating the introduction of CTA+ within the clay interlamelar space. This interlamelar space was further increased after polymerization for all of the three differently modified clays studied, indicating that in situ polymerization occurred. The introduction of organically modified clays did not influence the kinetics of polymerization. Stable latexes were obtained. The DMTA presented improved mechanical properties for the materials charged with two of the modified clays studied when compared to a conventional composite. SAOS analysis revealed that an exfoliated structure might have been obtained when adding one of the modified clays to the reacting medium. Cobb tests showed that the permeability to water was reduced by the incorporation of clays to the copolymer.
Study on Element Migration from Plastic Food Packagings to Simulating Solutions
Authors: Soares Eufemia Paez , Saiki Mitiko
Published: February 2007

In the present study a radiometric method was established for element migration determination from plastic food packagings to simulating solutions of 3% acetic acid solution and of water. This radiometric method consisted in irradiating plastics with neutrons, followed by exposition for migration and measurement the radioactivity in food‐simulating solution. The experimental conditions used were 10 days of exposure at 40 °C. The migration was studied for packagings of water and dairy products. The results indicated the migration of Co, Cr and Sb to the simulating solutions. The advantages of this methodology are no necessity of blank analysis, as well as the use of high purity simulants. Moreover, it is possible to evaluate the migration to the food contents, instead of simulants. The detection limits of migration indicated the high sensitivity of the radiometric method.
Three‐Dimensional Observations of Grain Boundary Morphologies in a Cylinder‐Forming Block Copolymer
Authors: Jinnai Hiroshi , Yasuda Kaoru , Nishi Toshio
Published: February 2007

The grain boundary morphology of a cylinder‐forming poly(styreneblock‐isoprene) (SI) diblock copolymer was investigated using transmission electron microtomography (TEMT). The three‐dimensional (3D) morphologies of the grain boundaries between the two grains with different orientation angle, α, were investigated. In the present study, two kinds of grain boundary morphologies, α ≃ 90° and α ≃ 120°, were examined in 3D. It was found that, in the case of α ≃ 90°, most of the cylindrical domains bent at the grain boundary in order not to intersect each other, while the cylindrical domains were found to be smoothly connected and were continuous in the case of α ≃ 120°. The observed morphologies indicated that the chain conformation inside the cylindrical microdomains plays more significant role than the segmental interaction between the two blocks.
Production of a Clay‐Polymer Composite Aiming the Removal of Residual Sodium from Biodiesel
Authors: Lopes Toni Jefferson , Gonçalves Odinei Hess , Quadri Mara Gabriela Novy , Machado Ricardo Antonio Francisco , Quadri Marintho Bastos
Published: February 2007

Clay particles are frequently used in adsorption processes with aqueous solution, but the formed colloidal dispersion is responsible for several phenomena that hinder the flow. To overcome these problems, this work deals with adsorption experiments carried out using an adsorptive media prepared with clay immobilized on the surface of polymer pellets. The effect of biodiesel on three polymer pellets and on a clay‐polymer composite was evaluated. Only the composite was not affected by the biodiesel, and its optimal operational conditions were determined. The composite was effective to remove residual sodium from biodiesel, attaining levels below law requirements.
Morphological Parameters of PP/PA6 Blend Measured In‐Line During Extrusion
Authors: Pinheiro Luís Antonio , Bitencourt Celina Souza , Pessan Luiz Antonio , Canevarolo Sebastião Vicente
Published: February 2007

An optical detector, assembled at a slit die at the exit of a twin screw extruder was used to quantify in‐line the extrusion of a PP/PA6 immiscible blend. During the extrusion the detector respond according to the changes in concentration and particle size of the polyamide 6 phase. The influence of dispersed phase concentration was evaluated varying its concentration from 0 to 5% (w/w). Reduction in the PA6 particle size was followed adding different amounts of polypropylene grafted with acrylic acid (PP‐g‐AA), which acts as a compatibilizer. The normalized detector signal intensity increases with an increase in PA6 concentration, due to an increase in the number of scattering particles in the medium, and with a decrease in its particle size. Plots of detector signal as a function of particle concentration and size enabled the calculation of the extinction cross sections of the PA6 segregated particles.
Glassy‐Crystalline Nanostructured Polymers Via Reactive Blending
Authors: Iliopoulos Ilias , Leibler Ludwik , Freluche Mathilde , Flat Jean‐Jacques , Gerard Pierre
Published: February 2007

Nanostructured glassy‐crystalline blends were obtained by reactive blending of poly(methyl methacrylate) (PMMA), or of poly(methyl methacrylate)‐b‐poly‐(n‐butyl acrylate)‐b‐poly(methyl methacrylate) (MBM) triblock copolymer, with polyamide‐6 (PA). The PMMA chain, or block, contains a low fraction of glutaric anhydride units which are strongly reactive toward the terminal amino group of PA. Under the blending conditions the grafting reaction is very efficient leading to a high fraction of graft copolymer. When the PA is short, Mn = 2500, nanostructured blends are obtained with both PMMA and MBM while for longer PA, Mn = 15000, nanostructures form only with the triblock MBM copolymer. The intrinsic property of MBM to self‐organize in lamellar‐like morphology seems to favour the nanostructure formation in the final blend. The resulting materials exhibit unique properties such as transparency, creep resistance and solvent resistance.
Polymers of Intrinsic Microporosity (PIMs): High Free Volume Polymers for Membrane Applications
Authors: Budd Peter M. , McKeown Neil B. , Fritsch Detlev
Published: February 2007

We are developing new types of polymer – termed polymers of intrinsic microporosity (PIMs) – which in the solid state behave like molecular sieves. As pervaporation membranes, they show selectivity for organics over water. As gas separation membranes, they exhibit a remarkable combination of high permeability and good selectivity for gas pairs such as O2/N2.
Sulfonated SEBS Membranes for HVAC Systems
Authors: Hwang Hae Young , Ha Seong Yong , Nam Sang Yong
Published: February 2007

A series of partially sulfonated SEBS(polystyrene‐b‐poly(ethylene‐r‐butylene)‐ b‐polystyrene) was synthesized. The sulfonation degree of the sulfonated SEBS, that reacted with acetyl sulfate, was characterized by FT‐IR and elementary analysis. Water permeability, water sorption (which strongly affect proton conductivity), and DSC (to determine the amount of bound water and free water) were investigated for application of sulfonated SEBS for HVAC system. It was observed that increasing sulfonation degree water permeability, water sorption, and bound water content increased. It revealed that sulfonation of SEBS membrane contributes to elevate hydrogen bonding between water vapour and hydrophilic polymer.
Oligomerization of Bovine Hemoglobin and Characterization of the Potential Blood Substitutes
Authors: Lima Maria Celiana Pinheiro , Pinto Patrícia Reis , Andrade Cristina Tristão
Published: February 2007

Bovine hemoglobin (HbBv) was isolated from whole blood and additionally purified by anion exchange chromatography. To obtain derivatives potentially suitable as oxygen carriers, oxidized trehalose was used as cross‐linking reagent. Intra‐ and intermolecular bonds were formed by reaction between reactive aldehyde groups of oxidized trehalose and primary amine groups on the protein surface. After reduction of the Schiff bases formed, the HbBv derivatives were characterized by high performance liquid chromatography (HPLC), electrophoresis and by ultraviolet spectroscopy to evaluate methemoglobin contents.
Solid State Nitric Oxide Sensor Using a Latex Rubber Matrix
Authors: Herculano R. D. , Brunello C. A. , Graeff C. F. O.
Published: February 2007

In this work we propose a sensor made of a spin trap (iron(II)‐diethyldithiocarbamate complex, FeDETC) encapsulated in a latex rubber matrix. Latex was used as solid matrix due to its excellent mechanical properties, biocompatibility and natural angiogenic properties. The fabrication and optimization processes were done by varying: FeCl36H2O and DETC concentrations in the system, polymerization temperature, FeDETC/latex ratio. The sensor presents high stability, the observed Electron Paramagnetic Resonance signal can be detected even after the sensor is exposed to ambient atmosphere for 40 days. It can be reused and is able to measure NO concentration as low as 0,1 mM. These results make NO‐FeDETC in the rubber matrix a promising NO sensor.
Preparation of Biocompatible Materials and Their Evaluation
Authors: Nakabayashi Nobuo
Published: February 2007

Biomedical application of polymers is an important topicin polymer society. Firstly, we have applied polymers developed for general usage. There has also been a need to prepare speciallydesigned polymers to substitute or assist lost or diseased function of tissues and organs to improve quality of patients' lives. There was a big demand for non‐thrombogenic materials to develop artificialheart. 2‐Methacryloyloxyethyl phosphorylcholine (MPC) was prepared and functions of MPC copolymers were evaluated. MPC is a promising methacrylate to develop several advanced artificialorgans and therapeutic instruments requiring fouling‐free, bloodcompatibility, permeability, biocompatibility, etc.
The Influence of the Chemical Additives in Polystyrene on the Features of Flocculants Obtained during Sulphonation of the Polystyrene
Authors: Sułkowski Wiesłw W. , Wolińska Agnieszka , Pentak Danuta , Maślanka Sławomir , Sułkowska Anna
Published: February 2007

Sumary: One of the ways of polymer waste management is its chemical modification. Waste polystyrene foam (EPS) and virgin polystyrene (VPS) as reference material were converted into polymeric flocculants by chemical reactions. One of the most popular and widely used procedures to follow the flocculation kinetics is the monitoring of the turbidity as a function of the polyelectrolyte dosage. The application of the obtained products caused a significant decrease of turbidity of the studied solutions. The products were successfully used as flocculants in the treatment of waste water. A colloid system composed of ferrum(III) hydroxide formed the discharge model.
Reinforcing of Elastomers with Mesoporous Silica
Authors: León D. Pérez , Luis F. Giraldo , Betty L. López , Hess Michael
Published: February 2007

Abstract: Mesoporous silica is used as filler for styrene–butadiene rubber (SBR); filler–polymer interactions are compared with those exhibited when commercial ultrasil silica (VN3) is used. A silane coupling agent is added to improve the filler dispersion and its influence on the bound rubber formation is also investigated before vulcanization. The bound rubber content is higher for the mesoporous silica and increases further for the sample containing alquil silanes improving the mechanical properties. For vulcanized samples, the reinforcing is measured by the vulcanization degree and the mechanical properties. The swelling degree, elastic modulus and glass transition temperature (Tg) are higher for samples containing mesoporous silica and increased by the use of organosilane (bis‐ trietoxisililpropil tetrasulfano (TESPT) or bis‐trietoxisililpropil disulfano (TESPD) during vulcanization. The vulcanization kinetics of the SBR is evaluated by rheometry and differential scanning calorimetry. The vulcanization rate is higher for the rubber filled with mesoporous silica indicating its autocatalytic effect. This can be explained by chemical interactions between the filler and rubber and the penetration of the rubber chains into the mesopore.
Various Ways to Reduce Zinc Oxide Levels in S‐SBR Rubber Compounds
Authors: Heideman Geert , Noordermeer Jacques W.M. , Datta Rabin N. , van Baarle Ben
Published: February 2007

Because of environmental concerns, the zinc content in rubber compounds has come under scrutiny. The research described in this article encompasses zinc‐oxide, various zinc‐complexes and alternative metal oxides as activators for sulphur vulcanisation. Regarding zinc complexes, it can be concluded that zinc‐ m‐glycerolate is a good substitute for ZnO as activator for sulphur vulcanisation in s‐SBR rubber, without detrimental effects on the cure characteristics. Of particular interest is also the positive effect of CaO and MgO in s‐SBR, while BaO, Cu(II)O and BeO hardly show any activation. The present article also reports on the application of a novel activator for sulphur vulcanisation: ZnClay. Results with s‐SBR rubber demonstrate, that this ZnClay can substitute conventional ZnO, retaining the curing and physical properties of the rubber products, while significantly reducing the environmental impact. A reduction of the zinc concentration with a factor 10 to 20 can be realised. Model Compound Vulcanisation studies are used to gain insight into the mechanism of this activator.
MRI of intravenously injected bone marrow cells homing to the site of injured arteries
Authors: Gao Fabao , Kar Sourav , Zhang Jiangyang , Qiu Bensheng , Walczak Piotr , Larabi Malika , Xue Rong , Frost Emma , Qian Zhiping , Bulte Jeff W. M. , Yang Xiaoming
Published: February 2007

The aim of this study was to test the feasibility of using MRI to detect magnetically labeled, intravenously injected bone marrow (BM) cells homing to injured arteries. In the first phase, BM cells from LacZ‐transgenic or green fluorescent protein (GFP)‐transgenic mice were transplanted into eight recipient mice. The left femoral arteries of recipient mice were injured using a cuff‐constriction or endothelium‐damage approach, and the right femoral arteries were uninjured to serve as controls. The location and distribution of migrated LacZ‐BM or GFP‐BM cells were confirmed with histology. In the second phase, BM‐derived cells from LacZ‐transgenic mice were labeled with superparamagnetic iron oxide (Feridex) and then transplanted into eight recipient mice with cuff‐induced injuries in the left femoral arteries. Migrated Feridex/LacZ‐BM cells were monitored in vivo using a 4.7 T MR scanner. Subsequently, high‐resolution ex vivo MRI was performed on 9.4 T and 11.7 T. LacZ‐positive or GFP‐positive cells in the thickened adventitia of the injured arteries were evident on histology. Both in vivo and ex vivo MRI showed larger regions of hypointensity with Feridex‐labeled cells at the sites of the injured arteries compared with control arteries (P < 0.01). This study provides initial evidence that may support the potential use of MRI to detect homing of intravenously injected BM cells to injured arteries. Copyright © 2007 John Wiley & Sons, Ltd.
The neurological basis of occupation
Authors: Gutman Sharon A , Schindler Victoria P
Published: February 2007

The purpose of the present paper was to survey the literature about the neurological basis of human activity and its relationship to occupation and health. Activities related to neurological function were organized into three categories: those that activate the brain's reward system; those that promote the relaxation response; and those that preserve cognitive function into old age. The results from the literature review correlating neurological evidence and activities showed that purposeful and meaningful activities could counter the effects of stress‐related diseases and reduce the risk for dementia. Specifically, it was found that music, drawing, meditation, reading, arts and crafts, and home repairs, for example, can stimulate the neurogical system and enhance health and well‐being, Prospective research studies are needed to examine the effects of purposeful activities on reducing stress and slowing the rate of cognitive decline. Copyright © 2007 John Wiley & Sons, Ltd.
Evaluation of energy policies for promotion and dissemination of photovoltaic technology in Italy
Authors: Aste N. , Adhikari R. S. , Tagliabue L. C.
Published: February 2007

The present paper describes three case studies of photovoltaic installation integrated in shelters and realised between 2003 and 2005 under the Italian national financing programme Tetti Fotovoltaici (PV Roofs) based on Subsidy Grant Scheme. These multifunctional shelters, located near to school buildings, offer a suitable protection for bicycles and motorbikes of the students and the employees of the schools and, at the same time, produce electric energy from photovoltaic modules integrated in the roof of the structure. Based on net present value (NPV) calculations, an economical feasibility analysis is carried out for these three PV installations. Further, for a comparison purpose, the calculations have also been made considering (hypothetically) if these systems were realised under the new Italian financing programme Conto Energia, based on Feed in Tariffs Scheme, recently launched in Italy and substitutive of the previous one. For the environmental benefits derived from these plants, also the preliminary results are presented on the avoided GHG emission to the atmosphere. Copyright © 2007 John Wiley & Sons, Ltd.
Mapping the 5–50‐kDa fraction of human amniotic fluid proteins by 2‐DE and ESI‐MS
Authors: Gianazza Elisabetta , Wait Robin , Begum Shaina , Eberini Ivano , Campagnoli Monica , Labò Sara , Galliano Monica
Published: February 2007

This report presents a proteomic analysis and provides a reference map of the 5–50‐kDa components of normal amniotic fluid collected in gestational weeks 16–18. Early amniocentesis samples were pooled and proteins with molecular mass lower than albumin were separated by gel filtration chromatography. The 2‐DE protocol was optimized for the separation of the small proteins and peptides in the fraction of interest. A total of 132 Coomassie blue‐stained protein spots were analyzed, following in‐gel tryptic digestion, by ESI‐MS/MS and 49 different gene products were identified. The treatment with alkaline phosphatase caused the shift of the phosphoisoforms of insulin‐like growth factor‐binding protein‐1 and of the N‐terminal osteopontin fragment. Of the 33 full‐length proteins identified in the 2‐DE profile, 23 had not been previously detected in the amniotic fluid and, of these, 22 are not present in the human plasma proteome under physiological conditions. Fragments of 16 larger proteins were identified and the sequence coverage data revealed that several correspond to autonomous domains that may have biological roles on their own. Several of the detected proteins and peptides appear to be involved in critical regulatory processes associated with placentation and early development, thus representing potential markers of various physiological or pathological conditions.
Spin‐Hall effect in a finite 2D Rashba electron system
Authors: Liu S. Y. , Horing Norman J. M. , Lei X. L.
Published: February 2007

The spin‐Hall effect in semiconductors with spin‐orbit coupling has been extensively investigated recently. However, such spin‐Hall current was shown to vanish quite generally in the diffusive regime in infinitely large two‐dimensional (2D) semiconductors with Rashba spin‐orbit interaction. Here, employing a kinetic equation approach, we investigate the spin‐Hall effect in finite‐size Rashba 2D semiconductors. We find that the fluctuation of electron density near the sample boundaries may give rise to a nonvanishing spin polarization, notwithstanding the vanishing of spin‐Hall current. With decreasing impurity density, the spin polarization increases. Our result indicates that the spin‐Hall current does not directly relate to spin accumulation, the latter of which may be observed experimentally. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Selective deposition of gold nanoparticles using Van der Waals interactions
Authors: Viallet B. , Ressier L. , Grisolia J. , Peyrade J. P. , Podgajny R. , Amiens C. , van den Boogaart M. A. F. , Brugger J.
Published: February 2007

Gold nanoparticles with hydrophobic surface have been deposited on a silicon substrate chemically patterned by reactive ion etching through a stencil mask and chemical vapour deposition of alkyl silanes. After deposition by dipping and adequate rinsing, the density of nanoparticles was found twice higher on the chemical patterns due to a difference of solvent affinity between patterned and bare silica. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Rapid quantitative determination of free fatty acids in fats and oils by fourier transform infrared spectroscopy
Authors: Ismail A. A. , van de Voort F. R. , Emo G. , Sedman J.
Published: February 2007

Rapid direct and indirect Fourier transform infrared (FTIR) spectroscopic methods were developed for the determination of free fatty acids (FFA) in fats and oils based on both transmission and attenuated total reflectance approaches, covering an analytical range of 0.2–8% FFA. Calibration curves were prepared by adding oleic acid to the oil chosen for analysis and measuring the C=O band @ 1711 cm–1 after ratioing the sample spectrum against that of the same oil free of fatty acids. For fats and oils that may have undergone significant thermal stress or extensive oxidation, an indirect method was developed in which 1% KOH/methanol is used to extract the FFAs and convert them to their potassium salts. The carboxylate anion absorbs @ 1570 cm–1, well away from interfering absorptions of carbonyl‐containing oxidation end products that are commonly present in oxidized oils. Both approaches gave results comparable in precision and accuracy to that of the American Oil Chemists’ Society reference titration method. Through macroprogramming, the FFA analysis procedure was completely automated, making it suitable for routine quality control applications. As such, the method requires no knowledge of FTIR spectroscopy on the part of the operator, and an analysis takes less than 2 min.
Polymorphic stability of hydrogenated palm oleins in dilutions with unhydrogenated liquid oils
Authors: deMan L. , Xu Y. J. , Chen H. S. , deMan J. M.
Published: February 2007

Palm oil was hydrogenated under selective and nonselective conditions. Some of the hydrogenated samples were chosen for their physical characteristics and were diluted with 70% sunflower oil. A commercial hydrogenated palm olein (H‐olein) was diluted up to 80% with canola oil. The diluted mixtures were evaluated for their polymorphic β' stability by a temperature‐cycling procedure between 4 and 20°C. All of the mixtures were stable in the β' form. The dropping point and solid fat content of the mixtures were compared with those of commercial soft and stick margarines. Soft margarines can be prepared from mixtures of 20% H‐olein and 80% unhydrogenated oil, and stick margarines from 40% H‐olein and 60% liquid oil. If canola oil is the liquid oil, the saturated content in the soft formulation is 13% and that of a stick formulation 17%.
Interaction of amylopectin with monoglycerides in model systems
Authors: Batres Lilian V. , White Pamela J.
Published: February 2007

The ability of glyceryl monomyristate (GMM), glyceryl monopalmitate (GMP) and glyceryl monostearate (GMS) to form insoluble complexes with amylopectin was studied in model systems. Amylopectin complexed to the greatest extent with GMP, followed by GMM and GMS, respectively. The degree of complex formation was statistically different (p<0.01) among monoglycerides. Iodimetric titrations of the complexes showed that the presence of GMP and GMM in the model systems significantly (p<0.01) decreased the iodine affinity of the amylopectin when compared with the control. The presence of GMS in the model systems decreased the iodine affinity of the amylopectin slightly but not with statistical significance. The decrease in iodine affinity caused by the three monoglycerides was statistically different (p<0.01) among treatments. There was a negative linear relationship between the yield of complex and the amount of monoglyceride (MG) and the iodine affinity of the complexes. No conclusion about the nature of the interaction between amylopectin and the MG could be made by doing infrared and NMR analyses of the model systems.
Fractionation of commercial frying oil samples using sep‐pak cartridges
Authors: Sebedio J. L. , Septier Ch. , Grandgirard A.
Published: February 2007

Commercial frying oil samples were fractionated by column chromatography on hydrated silicic acid according to the standardized DGF‐IUPAC‐AOAC method. The non‐polar fraction was isolated using a mixture of petroleum ether:diethyl ether (87:13), while the polar fraction was eluted by diethyl ether. These used frying oil samples were also fractionated using Sep‐Pak cartridges. The non‐polar fraction was eluted with 20 ml of a mixture of petroleum ether:diethyl ether (92:8), while the polar fraction was eluted with methanol.

The purity of each fraction was studied by thin layer chromatography (TLC) and by the Iatroscan TLC/FID system using a mixture of hexane:tetrahydrofuran:acetic acid (97:3:1) as solvent system.

The Sep‐Pak and the standardized methods gave similar results. This indicates that the state of degradation of a frying oil (detection of polar components) could be studied using Sep‐Pak cartridges, which is less time‐ and solvent‐consuming than column chromatography.
Diozonide of jojoba wax as intermediate for synthesis
Authors: Zabicky Jacob , Mhasalkar Moshe
Published: February 2007

Jojoba wax reacts with ozone yielding diozonide, which is a viable synthetic intermediate. The diozonide of jojoba wax is a white solid of low titre which decomposes violently around 110–120 C. We have studied several synthetic methods based on the diozonide, such as the preparation of dialdehyde; the corresponding dicarboxylic acid, and derivatives of the latter, such as metal soaps, esters and polyesters. Many additional paths may start from the diozonide intermediate and its derivatives.
Monomeric N‐hydroxyethylated amides
Authors: Sonnet Philip E. , Piotrowski Edwin G. , Wise William B. , Micich Thomas J.
Published: February 2007

Oxyethylated amides that are good wetting agents have been prepared as mixtures by allowing amides to react with ethylene oxide under base catalysis. Individual components of such mixtures can be synthesized by allowing 1‐alkylaziridines to react with p‐toluenesulfonic acid in monomethylethers of di‐, tri‐ and tetraethylene glycol used as solvents. The aminoethers are then acylated, and the methylether group is removed with trimethylsilyliodide from the resulting amide ethers. The sequence should allow the synthesis of specific wetting agents of quite varied structure (alkyl, aryl groups) with an option for isotopic labeling for more detailed analysis of the wetting properties.
Synthesis and properties of new cationic surfactants
Authors: Pegiadou‐Koemtjopoulou S. , Tsatsaroni E.
Published: February 2007

New pyrimidinium cationic surfactants containing a positively charged nitrogen atom of the pyrimidine ring and a long‐chain alkyl group of 6,8,10,12,14 carbon atoms were prepared. The structural assignment of these compounds was made on the basis of the elemental analysis and spectroscopic data, infrared, nuclear magnetic resonance and mass spectroscopy. Surface tension and after‐treatment of direct dyed cotton fabrics were determined for these surfactants. Antibacterial activities also were examined.
The determination of tocopherol content during the commercial processing of soybean oil
Authors: Rawlings H. W. , Kuhrt Noel H. , Baxter J. G.
Published: February 2007

A method for the analysis of the total tocopherols in soybean oil has been presented, and judged by distillation and other procedures is estimated to be accurate to within 10%. A discussion is made of the tocopherol to within 10%. A discussion is made of the tocopherol losses in various steps of soybean oil refining.
Temperature and frequency dependence of ultrasonic velocity and absorption in sperm and seal oils
Authors: Kuo Hung‐Liang , Weng Jung‐Shien
Published: February 2007

The variation of ultrasonic velocity and absorption in sperm oil and seal oil with temperature range of 5–55 C and frequency range of 1.5–60 MHz are measured. In both oils, the velocity increases ca. linearly with decreasing temperature and increases with increasing frequency; the absorption increases not only with decreasing temperature but also with decreasing frequency.
Gas‐liquid chromatography of hydroxy fatty esters: Comparison of trifluoroacetyl and trimethylsilyl derivatives
Authors: Freedman Bernard
Published: February 2007

Transformations of hydroxy to keto fatty esters have been monitored successfully by converting the hydroxy compounds to their trifluoroacetyl (TFA) or trimethylsilyl (TMS) derivatives followed by gas‐liquid chromatography (GLC). The TFA derivatives have shorter retention times, are better separated from the keto esters, and permit more complete resolution of saturated and unsaturated hydroxy fatty esters than the TMS derivatives. Improved methods for derivative preparation which are rapid and convenient are described. Methyl dimorphecolate (methyl 9‐hydroxy‐trans,trans,10,12‐octadecadienoate), which is thermally unstable and cannot be chromatographed as the trifluoroacetate or free hydroxy compound, was chromatographed satisfactorily as the trimethylsilyl ether.
Are green caterers more likely to serve healthy meals than non-green caterers? Results from a quantitative study in Danish worksite catering
Authors: Mikkelsen BE , Bruselius-Jensen M , Andersen JS , Lassen A
Published: February 2007

Objective

The present study aimed to investigate whether organic conversion in catering has positive effects on the nutritional quality of menus offered.

Design

The methodology was based on a self-administered questionnaire. The self-declared priority given to the use of organic foods was measured as the basis for assigning catering managers to one of two groups: ‘green’ or ‘non-green’ caterers. These groups were then compared with regard to the relative nutritional quality of the menu options offered to customers.

Setting

The study was carried out among randomly selected Danish worksite catering outlets.

Subjects

The subjects participating in the study comprised 526 Danish worksite catering managers.

Results

The results showed a strong correlation between caterers' ‘green-ness’ and the nutritional quality of the menu options offered. Green caters had more healthy options in their menus than non-green caters, which is likely to result in improved nutritional quality of the diets of end consumers. The reason for this may partly be the increased service training efforts that green caterers practise in order to be able to implement organic foods successfully. It may also be associated with the fact that the price premiums and availability of the organic products forces caterers to serve menus with higher amounts of root and non-green leafy vegetables, pulses and seasonal vegetables.

Conclusion

The present findings suggest that organic conversion of public canteens may be a good opportunity to promote healthier eating in public catering.
Validation of an estimated food record
Authors: Chinnock Anne
Published: February 2007

Objective

To validate an estimated food record (EFR), using a weighed food record (WFR) as the reference method, for the determination of food consumption and nutrient intakes in a group of Costa Rican adults.

Design

For the WFR, all foods consumed by subjects during seven consecutive days were weighed and recorded by nutrition students. Two EFRs (a 4-day and a 3-day record) were recorded by subjects with the use of home measures and photographs to estimate amounts.

Setting

Costa Rica.

Subjects

Sixty adults: 30 men and 30 women; 30 living in urban and 30 in rural areas.

Results

The EFR gave statistically significant lower average intake estimates for energy and 12 of the 22 nutrients examined. The correlation coefficients ranged from 0.68 (polyunsaturated fats) to 0.87 (calcium). The percentage of subjects classified into the same quartile ranged from 45.0% (polyunsaturated fats) to 68.3% (vitamin B12). For all nutrients except vitamin C, 0 or 1.7% were misclassified into extreme quartiles. For food group consumption, the EFR gave statistically significant lower estimates for six of the 17 groups and correlation coefficients ranged from 0.22 (fish) to 0.93 (beverages). Greater differences in estimates of mean energy and nutrient intakes were detected among subjects from rural areas, caused in part by a tendency to underestimate the amounts of rice and beans consumed.

Conclusion

Validation of the EFR using a WFR as the reference method gave results that compare favourably with those reported by other authors, and support the use of the EFR for dietary surveys among Costa Rican adults.
A comparison of the availability and affordability of a market basket in two communities in the Chicago area
Authors: Block Daniel , Kouba Joanne
Published: February 2007

Objective

The purpose of the present study was to characterise the food landscape of an inner city African American neighbourhood and its mixed-race suburban neighbour. Detailed analysis focuses on the relationship between community store mix and price, availability and produce quality.

Design

A market basket study was completed by members of the Chicago Food Systems Collaborative. The US Department of Agriculture's standard market basket survey and methodology were used. Additional items and analyses were added in consultation with community members.

Setting

Austin is a lower-middle-class African American community of 117 500 on the western edge of Chicago. Oak Park, which borders Austin, is an upper-middle-income suburb of 52 500 with a mixed racial profile.

Subjects

A market basket survey of every retail food store in Austin and Oak Park was completed. A total of 134 were included.

Results

Results indicate that Austin has many grocery stores and few supermarkets. Many Austin groceries stores carry produce that is usually competitively priced, but often of unacceptable quality. Supermarkets had the best selection. Prices were lowest at discount supermarkets. Prices of packaged items were higher at independent stores than at chain supermarkets, but fresh items were cheaper.

Conclusions

Food access is related more to store type than number. In this study, item availability and produce quality varied greatly between store types. Price differences were complicated and varied by store type and food category. This has consequences in terms of food purchasing decisions and dietary quality that public health professionals should acknowledge.
From flood basalts to the inception of oceanization: Example from the 40Ar/39Ar high‐resolution picture of the Karoo large igneous province
Authors: Jourdan F. , Féraud G. , Bertrand H. , Watkeys M. K.
Published: February 2007

The Jurassic Karoo large igneous province consists of vast quantities of basaltic lava flows, giant dike swarms, and poorly dated silicic magmatism. The Karoo magmatism occurred over more than 3 × 106 km2 and was associated with the opening of the Indian Ocean. We present new 40Ar/39Ar geochronological data concerning the easternmost part (i.e., the Mwenezi and Lebombo areas) of the Karoo province, close to the future rifted margin. These data allow documenting the final history of the province and the time elapsed between the end of the Karoo magmatism and the inception of oceanization. This important type of information is poorly constrained for most of the large igneous provinces. Eighteen plagioclase separates yielded 14 plateau and “mini‐plateau” ages obtained on 3 basaltic dikes (178.1 ± 1.1 to 177.2 ± 2.4 Ma; 2σ), 3 gabbroic (178.2 ± 1.7 to 176.8 ± 0.7 Ma) and 2 silicic (175.8 ± 0.7 to 174.4 ± 0.7 Ma) plutons, and 1 rhyolitic lava flow (177.8 ± 0.7 Ma). We also obtained three concordant plateau and mini‐plateau ages ranging from 173.9 ± 0.7 Ma to 172.1 ± 2.3 Ma on the atypical E‐MORB‐like N–S striking Rooi Rand dikes. One dike from the Save‐Limpopo N70°‐oriented giant dike swarm provides a mini‐plateau age of 177.7 ± 0.8 Ma in agreement with the dates previously determined on this branch and possibly assessing the same age and short duration (≤1–2 Myr) as for the 179 Ma giant Okavango dike swarm. New and previous selected age data obtained on the Karoo province show that the magmatism was active over ∼10 Myr from 184 to 174 Ma. The main basaltic phase occurred mostly over the first ∼5 Myr and was progressively followed by a more differentiated and less voluminous magmatism over the last 4 Myr. The easternmost Lebombo‐Mwenezi long‐lasting magmatism is interpreted as being triggered by the progressive lithospheric extension preceding the continental disruption. The transition from rifting to oceanization is probably illustrated by the E‐MORB‐like Rooi Rand dikes which are likely to be emplaced during or shortly after the final stage of the Karoo magmatism. A geodynamic evolution of the province is proposed. These data indicate that the Karoo magmatism represents an atypical province (admitting that other large igneous provinces are sufficiently known) with a long‐lasting and relatively low‐emission rate magmatic activity. It appears from a reevaluation of major Phanerozoic Continental Flood Basalts (CFBs) that for most of them, including the Karoo, the onset of oceanization shortly follows (or is coeval to) the latest CFB‐related activity more closely than previously thought.
Global analysis of scintillation variance: Indication of gravity wave breaking in the polar winter upper stratosphere
Authors: Sofieva V. F. , Kyrölä E. , Hassinen S. , Backman L. , Tamminen J. , Seppälä A. , Thölix L. , Gurvich A. S. , Kan V. , Dalaudier F. , Hauchecorne A. , Bertaux J.‐L. , Fussen D. , Vanhellemont F. , Fanton d' Andon O. , Barrot G. , Mangin A. , Guirlet M. , Fehr T. , Snoeij P. , Saavedra L. , Koopman R. , Fraisse R.
Published: February 2007

Stellar scintillations observed through the Earth atmosphere are caused by air density irregularities generated mainly by internal gravity waves and turbulence. We present global analysis of scintillation variance in two seasons of year 2003 based on GOMOS/Envisat fast photometer measurements. Scintillation variance can serve as a qualitative indicator of intensity of small‐scale processes in the stratosphere. Strong increase of scintillation variance at high latitudes in winter is observed. The maximum of scintillation variance can be associated with the polar night jet. The simplified spectral analysis has shown the transition of scintillation spectra toward small scales with altitude, which is probably related with turbulence appearing as a result of wave breaking. The breaking of gravity waves in the polar night jet seems to start in the upper stratosphere, a predicted, but not confirmed by observations before, feature. Weaker enhancements in tropics are also observed; they might be related to tropical convection.