bluuebunny/crossref_metadata_2025 huggingface dataset:
Fuel properties and emissions of soybean oil esters as diesel fuel
Authors: Chang David Y. Z. , Van Gerpen Jon H. , Lee Inmok , Johnson Lawrence A. , Hammond Earl G. , Marley Stephen J.
Published: November 2006

The effects of using blends of methyl and isopropyl esters of soybean oil with No. 2 diesel fuel were studied at several steady‐state operating conditions in a four‐cylinder turbocharged diesel engine. Fuel blends that contained 20, 50, and 70% methyl soyate and 20 and 50% isopropyl soyate were tested. Fuel properties, such as cetane number, also were investigated. Both methyl and isopropyl esters provided significant reductions in particulate emissions compared with No. 2 diesel fuel. A blend of 50% methyl ester and 50% No. 2 diesel fuel provided a reduction of 37% in the carbon portion of the particulates and 25% in the total particulates. The 50% blend of isopropyl ester and 50% No. 2 diesel fuel gave a 55% reduction in carbon and a 28% reduction in total particulate emissions. Emissions of carbon monoxide and unburned hydrocarbons also were reduced significantly. Oxides of nitrogen increased by 12%.
Turbidimetric measurement of haze in canola oil by acetone precipitation
Authors: Liu Hua , Przybylski Roman , Michael Eskin N. A.
Published: November 2006

Formation of turbidity in canola oil was facilitated with addition of acetone, and a method to measure the sediment content based on the oil turbidity has been developed. Canola oil was mixed with acetone at the ratio of 60:40, and the turbid solution developed in an ice bath for 20 min. The turbidity of the oil solution was determined by a turbidimeter. The relation between turbidity of the oil solution and sediment content was nonlinear and could be correlated by a second‐order polynomial. There was no difficulty in the development of turbidity in canola oil solutions in the presence of added lecithin (2%, w/w). However, with added lecithin, turbidity was 23% higher at the same sediment content.
Uses of biotechnology in modifying plant lipids
Authors: Budziszewski Greg J. , Croft Kevan P. C. , Hildebrand David F.
Published: November 2006

This review discusses fatty acid modification of oilseeds with additional emphasis on production of oxygenated derivatives. In a relatively short period, less than a decade, our understanding of the enzymes involved in plant fatty acid synthesis has increased to the point where we understand how they might be used in oilseed modification. Further, through modern molecular biological techniques, the actual genes for many of these important enzymes have been cloned. Use of genetic transformation systems has allowed us to fundamentally alter the normal biosynthetic pathways in highly specific ways, in manners that would be either difficult or impossible using traditional breeding techniques. Alteration of plant lipid biosynthesis is not restricted to using genes from the plants themselves, but interspecies transfer is possible, either from completely unrelated plant species (often of no commercial value but possessing unusual biochemical properties) or from animals, fungi, and prokaryotic organisms. In this way “designer” plants possessing altered metabolism, tailored to the interests or needs of certain industries, nutritionists, and the consumer can be created.
Eicosapentaenoic acid, but not docosahexaenoic acid, increases mitochondrial fatty acid oxidation and upregulates 2,4‐dienoyl‐CoA reductase gene expression in rats
Authors: Willumsen Nina , Vaagenes Hege , Lie Øyvind , Rustan Arild C. , Berge Rolf K.
Published: November 2006

The aim of the present study was to investigate whether eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) was responsible for the triglyceride‐lowering effect of fish oil. In rats fed a single dose of EPA as ethyl ester (EPA‐EE), the plasma concentration of triglycerides was decreased at 8 h after acute administration. This was accompanied by an increased hepatic fatty acid oxidation and mitochondrial 2,4‐dienoyl‐CoA reductase activity. The steady‐state level of 2,4‐dienoyl‐CoA reductase mRNA increased in parallel with the enzyme activity. An increased hepatic long‐chain acyl‐CoA content, but a reduced amount of hepatic malonyl‐CoA, was obtained at 8 h after acute EPA‐EE treatment. On EPA‐EE supplementation, both EPA (20:5n‐3) and docosapentaenoic acid (DPA, 22:5n‐3) increased in the liver, whereas the hepatic DHA (22:6n‐3) concentration was unchanged. On DHA‐EE supplementation retroconversion to EPA occurred. No statistically significant differences were found, however, for mitochondrial enzyme activities, malonyl‐CoA, long‐chain acyl‐CoA, plasma lipid levels, and the amount of cellular fatty acids between DHA‐EE treated rats and their controls at any time point studied. In cultured rat hepatocytes, the oxidation of [1‐14C]palmitic acid was reduced by DHA, whereas it was stimulated by EPA. In thein vivo studies, the activities of phosphatidate phosphohydrolase and acetyl‐CoA carboxylase were unaffected after acute EPA‐EE and DHA‐EE administration, but the fatty acyl‐CoA oxidase, the rate‐limiting enzyme in peroxisomal fatty acid oxidation, was increased after feeding these n‐3 fatty acids. The hypocholesterolemic properties of EPA‐EE may be due to decreased 3‐hydroxy‐3‐methylglutaryl‐CoA reductase activity. Furthermore, replacement of the ordinary fatty acids, i.e., the monoenes (16:1n‐7, 18:1n‐7, and 18:1n‐9) with EPA and some conversion to DPA concomitant with increased fatty acid oxidation is probably the mechanism leading to changed fatty acid composition. In contrast, DHA does not stimulate fatty acid oxidation and, consequently, no such displacement mechanism operates. In conclusion, we have obtained evidence that EPA, and not DHA, is the fatty acid primarily responsible for the triglyceride‐lowering effect of fish oil in rats.
Dietary fatty acid composition induces comparable changes in cardiolipin fatty acid profile of heart and brain mitochondria
Authors: McGree Carl D. , Lieberman Pamela , Greenwood Carol E.
Published: November 2006

The fatty acid profile of cardiolipin (CL) from brain and cardiac mitochondria was measured to determine whether CL isolated from these two tissue sources responded similarly to alterations in dietary fat composition. Male Wistar rats were fed 20% (w/w) diets containing 2 to 12% (w/w) 18∶2n‐6 for four weeks. Despite higher baseline levels of CL 18∶2n‐6 in cardiac (54±1% of total fatty acids) compared to brain (13±1%) mitochondria, CL 18∶2n‐6 levels increased in proportion to dietary 18∶2 levels. The degree of change in 18∶2n‐6 was comparable with both tissues showing an approximate 1.5‐ to 2‐fold increase. The time course of changes in CL fatty acid profile was examined in a subsequent experiment in which animals were fed 20% (w/w) fat diets containing either 3 or 15% α‐linoleate. Changes in cardiac CL 18∶1, 18∶2n‐6, and 22∶6n‐3 levels were observed within one week of feeding. While statistically significant differences were not observed in brain CL until the second week of feeding, the time course did not differ substantively from that observed in heart. The results from this study suggest that while baseline fatty acid profile of cardiac and neural CL differ, mitochondria from both tissues show comparable sensitivity to changes in dietary fat composition. Furthermore, it would appear that the turnover rate of fatty acids in CL is similar in both tissues.
Unusually high levels of eicosatetraenoic, eicosapentaenoic, and docosahexaenoic fatty acids in palestinian freshwater sponges
Authors: Dembitsky Valery M. , Rezanka Tomas
Published: November 2006

The fatty acid composition of three freshwater sponges—Ephydatia syriaca, Nudospongilla sp., andCortispongilla barroisi—were studied. Twenty principal fatty acids, and unusually high levels of eicosatetraenoic (5,8,11,14–20:4 up to 10.1% of the total acid mixture), eicosapentaenoic (5,8,11,14,17–20:5 up to 11.6%), and docosahexaenoic acids (4,7,10,13,16,19–22:6 up to 11.8%) were detected. The only demospongic acid found was 5,9,17‐hexacosatrienoic acid (1.8–3.7%).
AOCS collaborative study on sensory and volatile compound analyses of vegetable oils
Authors: Warner K. , Nelsen T.
Published: November 2006

An AOCS collaborative study was conducted to determine the effectiveness of sensory analysis and gas chromatographic analyses of volatile compounds in measuring vegetable oils for levels of oxidation that ranged from none to high. Sixteen laboratories from industry, government, and academia in Canada and the United States participated in the study to evaluate the flavor quality and oxidative stability of aged soybean, corn, sunflower, and canola (low‐erucic acid rapeseed) oils. Analytical methods included sensory analyses with both flavor intensity and flavor quality scales and gas‐chromatographic volatiles by direct injection, static headspace, and dynamic headspace (purge and trap) techniques. Sensory and volatile compound data were used to rank each of the oils at four levels of oxidation—none, low, moderate, and high. For soybean, canola, and sunflower oils, 85–90% of laboratories correctly ranked the oils by either analysis. For corn oil, only 60% of the laboratories ranked the samples according to the correct levels of oxidation by either analysis. Variance component estimates for flavor scores showed that the variation between sensory panelists within laboratories was lowest for the unaged oils. As storage time increased, the variance also increased, indicating that differences among panelists were greater for more highly oxidized oils. Between‐laboratory variance of sensory panel scores was significantly lower than within‐laboratory variance.
The antioxidant capacity of complex mixtures by kinetic analysis of crocin bleaching inhibition
Authors: Tubaro Franco , Micossi Elena , Ursini Fulvio
Published: November 2006

The capability of a compound or of a mixture of compounds to quench peroxyl radicals was measured by analyzing the kinetics of the competition of a parallel reaction where peroxyl radicals bleach the carotenoid crocin. This kinetic approach, originally described for the analysis of antioxidants reacting with hydroxyl radicals in water, was modified by both decreasing the polarity of the solvent, thus allowing the analysis of lipophilic compounds, and by substituting a source of peroxyl radicals for the hydroxyl radical generating system. Single compounds as well as complex mixtures were analyzed by kinetic data processing. Overall antioxidant capacity, relative to that of α‐tocopherol or of its soluble analog Trolox C, was calculated. As examples of the use of this test, the antioxidant capacities of a crude rosemary extract, Maillard reaction products, and virgin olive oils were measured.
Polymorphism of stabilized and nonstabilized tristearin, pure and in the presence of food emulsifiers
Authors: Elisabettini Paola , Desmedt Amélia , Durant François
Published: November 2006

The polymorphism of tristearin (SSS) was studied by means of differential scanning calorimetry and powder X‐ray diffraction. The influence of 5% in weight of different food emulsifiers—i.e., 1‐monostearin, sorbitan tristearate, and sugar monostearate—was also studied. Because polymorphism is sensitive to thermal treatment, two thermal conditionings were applied. According to the dynamic process (melting, quenching, and heating at 5°C/min), SSS showed three polymorphic forms: α, β′, and β1. The presence of the emulsifiers hindered the β′→β transformation, and a destructured β2 form was recorded. According to the stabilization process (stabilization at 57°C for various periods of time), SSS showed two β′ forms: β2′ and β1′. Three hours of stabilization were necessary to recover the whole triglyceride under the β form. The emulsifiers slowed down the polymorphic transition rates. Indeed, after six hours of stabilization, mixtures of β′ and β were observed. Sugar monostearate seemed to have the most powerful effect on the transition kinetics because large amounts of α form were detected.
Continuous supercritical carbon dioxide processing of palm oil
Authors: Ooi C. K. , Bhaskar A. , Yener M. S. , Tuan D. Q. , Hsu J. , Rizvi S. S. H.
Published: November 2006

Crude palm oil was processed by continuous supercritical carbon dioxide. The process reduces the contents of free fatty acids, monoglycerides and diglycerides, certain triglycerides, and some carotenes. The refined palm oil from the process has less than 0.1% free fatty acids, higher carotene content, and low diglycerides. Solubility of palm oil in supercritical carbon dioxide increased with pressure. A co‐solvent improves the refining process of palm oil.
Enzymatic synthesis of structured lipids: Transesterification of triolein and caprylic acid ethyl ester
Authors: Huang Kuan‐Hsiang , Akoh Casimir C.
Published: November 2006

Structured lipids were successfully synthesized by lipase‐catalyzed transesterification (ester interchange) of caprylic acid ethyl ester and triolein. The transesterification reaction was carried out in organic solvent as reaction media. Eight commercially‐available lipases (10% w/w substrates) were screened for their ability to synthesize structured lipid by incubating with 100 mg triolein and 78.0 mg caprylic acid ethyl ester in 3 mL hexane at 45°C for 24 h. The products were analyzed by reverse‐phase high‐performance liquid chromatography with evaporative light‐scattering detector. Immobilized lipase IM60 fromRhizomucor miehei converted most triolein into structured lipids (41.7% dicapryloolein, 46.0% monocapryloolein, and 12.3% unreacted triolein). However, lipase SP435 fromCandida antarctica had a higher activity at higher temperature. The reaction catalyzed by lipase SP435 yielded 62.0% dicapryloolein, 33.5% monocapryloolein, and 4.5% unreacted triolein at 55°C. Time course, incubation media, added water, and substrate concentration were also investigated in this study. The results suggest that lipase‐catalyzed transesterification of long‐chain triglycerides and medium‐chain fatty acid ethyl ester is feasible to synthesize structured lipids.
A detailed triglyceride analysis ofLesquerella fendleri oil: Column chromatographic fractionation followed by supercritical fluid chromatography
Authors: Hayes Douglas G. , Kleiman Robert
Published: November 2006

The triglyceride structure of oil fromLesquerella fendleri, a potential new U.S. crop, rich in C20 hydroxy fatty acids, was examined by silica gel column chromatographic fractionation followed by supercritical fluid chromatography. The analysis confirmed previous findings derived by our research group, but provided further detail. The analysis demonstrated the presence of trihydroxy triglyceride, which contained all of the oil’s C18 hydroxy acyl groups (present at less than 0.5% in the oil). Lipolysis indicated that these groups were located solely at the 2‐position. In addition, a strong correlation was detected between the presence of α‐linolenic (18:39,12,15) and auricolic (20:211,17 OH14) acids in triglycerides.
Identification of fatty acid methyl ester as naturally occurring transcriptional regulators of the members of the peroxisome proliferator‐activated receptor family
Authors: Schmidt Azriel , Vogel Robert L. , Witherup Keith M. , Rutledge Su Jane , Pitzenberger Steven M. , Adam Mohammed , Rodan Gideon A.
Published: November 2006

The nuclear hormone receptors NUC‐1 (PPARδ) and PPARα are members of the peroxisome proliferator‐activated receptor (PPAR) family. The members of this receptor family are activated by agents that stimulate peroxisome proliferation, free fatty acids, prostaglandin J2 metabolites, and agents considered for the therapy of insulin‐independent diabetes mellitus. To identify putative physiological agents that activate NUC‐1, we tested the ability of acetone extracts of various rat tissues to activate the transcription of an MMTV‐luciferase reporter gene, via a GR/NUC‐1 hybrid receptor. GR/NUC‐1 contains the ligand binding region of the NUC‐1 receptor and the DNA binding domain of the glucocorticoid receptor. Using this assay, we found stimulatory activity in the pancreas, which upon purification and characterization was identified as methylpalmitate, known to be enriched in pancreatic lipids. In addition, we determined that ethyl esters of palmitic and oleic acids are also potent activators of this receptor. thus, fatty acid ester formation may control the cellular concentrations of fatty acids, and acyl‐ester formation may play a role in the control of metabolic pathways and the activation of the PPAR.
Dietary docosahexaenoic acid has little effect on peroxisomes in healthy mice
Authors: De Craemer Dirk , Pauwels Marina , Van den Branden Christiane
Published: November 2006

NMRI mice were fed diets supplemented with 0.05, 0.2, or 2% (w/w) docosahexaenoic acid (DHA), a polyunsaturated fatty acid present in fish oil, for 3 d, 3 wk, or 3 mon. The doses of DHA were chosen to supply the mice with concentrations of DHA which approximate those that have been reported to be beneficial to patients with peroxisomal disease. Diets containing 0.05 or 0.2% DHA did not change hepatic, myocardial, and renal catalase (EC 1.11.1.6) activity except for a slight but significant increase (to 120%) in myocardial catalase activity in mice treated with the 0.05% DHA diet for 3 mon. A diet with 2% DHA induced myocardial catalase activity to 150% after both 3 d and 3 wk of administration. In the liver of mice fed this diet for 3 wk, hepatic catalase activity was increased to 140% while no induction of palmitoyl‐CoA oxidase (EC 1.3.99.3), urate oxidase (EC 1.7.3.3), andl‐α‐hydroxyisovalerate oxidase (EC 1.1.3.a) was observed. With the light microscope, no changes in peroxisomal morphology were visually evaluated in catalase stained sections of liver, myocardium, and kidney of mice fed either diet. Our results show that in healthy mice a low dietary DHA dose (<0.2%; this corresponds to a dose prescribed to peroxisomal patients) has no effect on several hepatic peroxisomal H2O2‐producing enzymes, including the rate‐limiting enzyme of the peroxisomal fatty acid β‐oxidation. This may indicate that such a DHA dose will not add a strong load on the often disturbed fatty acid metabolism in the liver of patients with peroxisomal disorders.
Alk‐1‐enylacyl, alkylacyl, and diacyl subclasses of native ethanolamine and choline glycerophospholipids can be quantified directly by phosphorus‐31 NMR in solution
Authors: Malewicz Barbara , Baumann Wolfgang J.
Published: November 2006

We show that phosphorus‐31 nuclear magnetic resonance spectroscopy can be used to distinguish and to quantify the alk‐1‐enylacyl, alkylacyl, and diacyl glycerophosphoethanolamine (GPE) subclasses, and the respective glycerophosphocholine (GPC) subclasses, in their native form without prior degradation or derivatization, provided the phospholipids are observed in the nonaggregated state. Monomeric phospholipid distribution is ascertained by recording the spectra, after removal of metal ions, on CDCI3/CD3OD/D2O (50∶50∶15, by vol) solutions. The utility of this approach is exemplified for the ethanolamine glycerophospholipids (EPL) from bovine brain and the choline glycerophospholipids (CPL) from bovine heart. Sharp and well‐resolved resonances are obtained for alkylacylGPE (+0.395 ppm; re 1% H3PO4), alkenylacylGPE (+0.353 ppm), and diacylGPE (+0.315 ppm), and for alkylacylGPC (−0.383 ppm), alkenylacylGPC (−0.436 ppm) and diacylGPC (−0.451 ppm). Integrated peak reas are shown to closely correlate with dose. Accurate quantitation of EPL and CPL subclasses at submicromolar levels can further be facilitated by use of synthetic dialkylGPE (+0.602 ppm) and dialkylGPC (−0.196 ppm) as internal standards. The method is simple, rapid, sensitive and reproducible, and permits the complete resolution and direct quantitation of all ethanolamine and choline glycerophospholipid subclasses quite independent of fatty chain length and degree of unsaturation.
Viscosity and its relationship to crystallization in a binary system of saturated triacylglycerides and sesame seed oil
Authors: Toro‐Vazquez Jorge F. , Gallegos‐Infante Alberto
Published: November 2006

This paper describes the relationship of viscosity with the crystallization process in a binary system formed by sasame oil and different concentrations of tripalmitin (TP) and tristerian (TS) (0.0, 0.032, 0.098, 0.18, 0.26, 0.344 g/dL). The behavior of the reduced viscosity (ηred) indicated that TP and TS affected the native bilayer lamellar organization of sesame oil triacylglycerides. The behaviour of ηred at TP or TS concentrations ≤0.098 g/dL suggested that, as a result of intermolecular interactions between the saturated triacylglyceride and the unsaturated triacylglycerides of sesame oil, the oil solution developed lamellar structures with a smaller size than the native structures in sesame oil. At TP or TS concentrations >0.098 g/dL, the behavior of ηred indicated that TP or TS segregated out of the lamellar structure as the temperature was decreased. The kinetics of the segregation phenomenon was a function of the concentration of saturated triacylglyceride and the type of triacylglyceride (i.e., TP or TS), and was favored by an increase in the shear rate. In all situations, the temperature of nucleation was achieved when ηred=0, which may represent the point at which the interfacial energy between sesame oil and the developing nuclei achieved its maximum value. The higher the intermolecular interaction between the TP or TS and the triacylglyceride structure of the sesame oil, the lower the temperature at which ηred=0 in the oil solutions. As a result, the diffusion term (i.e., viscosity of the liquid phase) became a limiting factor for crystal growth rate, especially at TP and TS concentrations ≤0.18 g/dL.
Phase diagrams for oil/methanol/ether mixtures
Authors: Boocock David G. B. , Konar Samir K. , Sidi Hanif
Published: November 2006

One‐phase transmethylations of vegetable oils with methanol to form methyl esters occur considerably faster than conventional two‐phase reactions. Addition of simple ethers is an efficient method for producing a single phase. Ternary phase diagrams have been determined at 23°C for oil/methanol/ether mixtures; these are useful when applying the one‐phase method across a wide range of conditions. Soybean, canola, palm, and coconut oils were used in combination with five ethers, namely, tetrahydrofuran (THF), 1,4‐dioxane (DO), diethyl ether (DE), diisopropyl ether (DI), andtert‐butyl methyl ether (TBM). All five ethers can produce miscibility for all methanol/oil compositions. The ether/methanol volumetric ratios required for miscibility at a methanol/soybean or canola oil volumetric ratio of 0.20 (5.4 molar ratio) at 23°C are: THF, 1.15; DO, 1.60; DE, 1.38 DI, 1.57; and TBM, 1.57. For THF, this results in one‐phase mixtures that contain 65 vol% oil. Soybean and canola oil form identical diagrams. Palm oil requires slightly less ether at the lower methanol concentrations, but coconut oil requires considerably less across the whole concentration range. Acid‐catalyzed reactions, when performed at the boiling point of the most volatile component, require less ether than predicted from the diagrams.
Low‐molecular weight organic composition of acid water from coconut oil soapstock
Authors: Sivasothy Arunthathi , Reilly Peter J.
Published: November 2006

Soapstock from alkaline refining of coconut oil was acidified, and the resulting acid water after neutralization was subjected to gas chromatography, electron‐ionization and chemical‐ionization mass spectroscopy, and high‐performance liquid chromatography. The chief low‐molecular weight organic components were C4−C18 fatty acids, hydroxylated acids, and sugar alcohols. The prevalence of acids and total absence of phosphate compounds make coconut acid water different in composition from the acid waters from other soapstocks.
Gas‐liquid chromatography‐mass spectrometry of the 4,4‐dimethyloxazoline derivatives of Δ5‐unsaturated polymethylene‐interrupted fatty acids from conifer seed oils
Authors: Berdeaux Olivier , Wolff Robert L.
Published: November 2006

The fatty acids from the seed oils of three Conifer species (one Pinaceae,Pinus pinaster, and two Cupressaceae,Chamaecyparis lawsoniana andBiota orientalis) have been analyzed as their 4,4‐dimethyloxazoline (DMOX) derivatives by gas‐liquid chromatography coupled with mass spectrometry. The structures of six Δ5‐unsaturated polymethylene‐interrupted fatty acids (Δ5‐UPIFA) were established, confirming previous studies in which they were identified by their equivalent chainlengths (ECL) and by comparison with related authentic standards. These acids were:cis‐5,cis‐9 18∶2,cis‐5,cis‐9,cis‐12 18∶3 (P. pinaster),cis‐5,cis‐9,cis‐12,cis‐15 18∶4 (C.lawsoniana),cis‐5,cis‐11 20∶2,cis‐5,cis‐11,cis‐14 20∶3 (all species),cis‐5,cis‐11,cis‐14,cis‐17 20∶4 (B. orientalis) acids. In addition,cis‐9 18∶1,cis‐9,cis‐12 18∶2 (all species) andcis‐9,cis‐12,cis‐15 18∶3 (Cupressaceae) acids, together with their elongation products [cis‐11 20∶1,cis‐11,cis‐14 20∶2 (all species) andcis‐11,cis‐14,cis‐17 20∶3 (B. orientalis) acids] were also identified. In the mass spectra, DMOX derivatives of all Δ5‐UPIFA showed an intense peak atm/z 153, which is a diagnostic ion of fatty acid derivatives with a Δ5‐ethylenic bond. Other double bonds were localized by ion pairs that differed by 12 atomic mass units. The present study fully justifies the use of ECL to identify Δ5‐UPIFA in Conifer seed oils, in which they are ordinary components.
Quantitative extraction of hamster liver lipid and cholesterol with supercritical carbon dioxide
Authors: Kahlon Talwinder S. , Chow Faye I. , Sayre Robert N.
Published: November 2006

A quantitative method for liver lipid and cholesterol extraction with supercritical CO2 and ethanol entrainer (SCE) is reported and compared with the Folch (chloroform/methanol) procedure. Mean values for lipid and cholesterol in hamster livers (n=48) were similar between the SCE and Folch methods. Correlation coefficients between the two methods were 0.9866 for total lipid and 0.9546 for cholesterol. Similar mean values and high correlations between the two methods validate the SCE procedure as a precise alternative method for quantitative liver lipid extractions. The SCE method also reduces the use of hazardous solvents.
Effect of heterospecifics on foraging of endangered red‐crowned and white‐naped cranes in the Korean Demilitarized Zone
Authors: Lee Sang Don , Jabłoński Piotr G. , Higuchi Hiroyoshi
Published: November 2006

We determined how the presence of heterospecific individuals in the vicinity of a focal individual affects the behavior of two critically endangered species of cranes on their wintering grounds at Cheolwon in the Korean Demilitarized Zone. The red‐crowned crane, Grus japonensis, is larger than the white‐naped crane, Grus vipio, and it dominates the white‐naped crane in aggressive interactions. We showed that the dominant species increases foraging activity in the presence of the subordinate species presumably because of scrounging of food from the subordinate. Because interspecific interactions may affect avian endangerments these behavioral findings should be taken into account when managing winter refuges for the two endangered crane species.
Genetische Befunde bei der Aufmerksamkeitsdefizit- und Hyperaktivitätsstörung (ADHS)
Authors: Schimmelmann Benno Graf , Friedel Susann , Christiansen Hanna , Dempfle Astrid , Hinney Anke , Hebebrand Johannes
Published: November 2006

Zusammenfassung: Die Aufmerksamkeitsdefizit- und Hyperaktivitätsstörung (ADHS) ist mit einer Prävalenz von 3-7% eine häufige kinder- und jugendpsychiatrische Störung. Auf der Basis formalgenetischer Studien ergibt sich eine Heritabilitätsschätzung von 60-80% für ADHS mit einem ca. 5-fach erhöhten Risiko für erstgradige Verwandte von Betroffenen. Bislang vier Genomscans lieferten potentiell relevante chromosomale Regionen, insbesondere den einheitlichen Kopplungsbefund auf 5p13. Aus einer Vielzahl von Assoziationsstudien zu Kandidatengenen deuten aktuelle Metaanalysen auf die Relevanz der Gene der dopaminergen Rezeptoren DRD4 und DRD5 sowie des serotonergen Rezeptors HTR1B und des Synaptosomal Assoziierten Proteins (SNAP-25). In Tiermodellen liegen vorwiegend Paradigmen für Hyperaktivität vor; diese sind in knockout- und Quantitative Trait Loci (QTL) Designs mit viel versprechenden Ergebnissen zum dopaminergen System untersucht worden. Es ist davon auszugehen, dass erst das Zusammenwirken verschiedener Gen-Varianten mit jeweils moderatem bis hin zu kleinem Effekt den Phänotyp ADHS bedingen (Oligo-/ Polygenie) und bei verschiedenen Betroffenen unterschiedliche Kombinationen von prädisponierenden Gen-Polymorphismen zu ADHS führen können. Entsprechend sind für molekulargenetische Studien große Fallzahlen notwendig und die bisherigen Befunde als vorläufig zu interpretieren. Zukunftsweisend für die molekulargenetische Aufklärung von ADHS sind SNP-basierte Genomscans, mit denen 10 000-1 000 000 einzelne Polymorphismen (SNPs) gleichzeitig untersucht werden können. Tiermodelle liefern Hinweise auf die Funktion relevanter Kandidatengene und tragen zur Erweiterung der bislang teilweise widersprüchlichen Kenntnisse zur Neurobiologie des ADHS bei.
Zur Genetik der Lese-Rechtschreibschwäche
Authors: Schulte-Körne Gerd , Warnke Andreas , Remschmidt Helmut
Published: November 2006

Zusammenfassung: Die Lese-Rechtschreibstörung (LRS) ist eine der häufigsten Entwicklungsstörungen. Die Ursachen dieser komplexen Störung sind bisher nur kaum verstanden. Familienuntersuchungen zeigen, dass die LRS familiär gehäuft auftritt und dass das Risiko für ein Geschwisterkind, eine LRS zu entwickeln, ca. 3,5fach erhöht ist. Verschiedene kognitive Fähigkeiten sind mit der LRS korreliert. Hierzu gehören die phonologische Bewusstheit, orthographisches Wissen, phonologisches Dekodieren, auditives Kurzzeitgedächtnis und schnelles Benennen. Eine familiäre Häufung dieser mit der LRS korrelierten Dimensionen und eine hohe Erblichkeit (Heritabilität) wurden wiederholt gefunden. Die Heritabilität für die Lesefähigkeit liegt zwischen 50-60%, für die Rechtschreibstörung zwischen 50 und 70%. Durch genomweite Kopplungsuntersuchungen wurden bisher 9 Kandidatengenregionen (DYX1-9) identifiziert. Vier Kandidatengene, DCDC2, KIAA0319, ROBO1 und DYX1C1 wurden kürzlich beschrieben. Diese beeinflussen die neuronale Migration und sind daher funktionell aussichtsreiche Kandidatengene für die LRS. Allerdings konnte bisher keine funktionell relevante Mutation gefunden werden. Die Komorbidität zwischen LRS und ADHD sowie LRS und Sprachentwicklungsstörungen könnte zum Teil durch gemeinsame genetische Faktoren erklärt werden. In der Zukunft wird es für die Ursachenforschung der LRS entscheidend sein, möglichst alle ursachenrelevanten Dimensionen gemeinsam an ausreichend großen Stichproben zu untersuchen. Neben den relevanten neurobiologischen Faktoren sollten auch Umweltfaktoren und die verschiedenen Interaktionen, wie z.B. Gen-Umwelt und Gen-Gen-Interaktionen untersucht werden. In einem europäischen, kollaborativen Forschungsvorhaben (NeuroDys) wird weltweit die größte Stichprobe von Kindern mit einer LRS gesammelt und untersucht, um durch ein verbessertes Ursachenverständnis unter Einschluss der Identifikation von genetischen Risikofaktoren die Komplexität des Störungsbildes besser zu verstehen und perspektivisch spezifische Therapien zu entwickeln.
Klinische Kinder- und Jugendlichen-Psychologie
Authors: Wyschkon Anne , Esser Günter
Published: November 2006

Zusammenfassung. Fragestellung: Welche Entwicklungstendenzen gibt es in der Klinischen Kinder- und Jugendlichen-Psychologie in den letzten Jahren und welche Perspektiven können daraus für zukünftige Forschungsbemühungen und Veröffentlichungen abgeleitet werden? Methode: Analyse der Artikel in der Zeitschrift für Klinische Psychologie und Psychotherapie der vergangenen vier Jahre. Ergebnisse: Im Zeitraum von 2002 bis 2005 befasst sich mit Ausnahme des Jahrganges 2004 etwa ein Fünftel der Originalarbeiten mit Kindern und Jugendlichen. Arbeiten, die ausschließlich Jugendliche betreffen, sind bisher eher die Ausnahme. Die meisten Publikationen beschäftigen sich mit Angststörungen bei Kindern und Jugendlichen. Diskussion: Eine Erhöhung der Themenvielfalt bei den Arbeiten zu Kindern und Jugendlichen, insbesondere im Bereich der diagnostischen Verfahren, der untersuchten Störungsbilder sowie im Hinblick auf den Einsatz vielfältiger Behandlungsmethoden, wäre wünschenswert.
Increased surface seawater pCO2 in the eastern Bering Sea shelf: An effect of blooms of coccolithophorid Emiliania huxleyi?
Authors: Murata Akihiko
Published: November 2006

Increased surface seawater pCO2 observed in the eastern Bering Sea shelf (long 168°W–160°W; lat 54°N–68°N) were examined in relation to blooms of the coccolithophorid Emiliania huxleyi, using data obtained from R/V Mirai cruises once or twice annually (August–October 1998–2002). A principal component analysis demonstrated that there are two spatial scales of pCO2 variability associated with E. huxleyi blooms. One is a small‐scale variation (∼0.2° in latitude), which shows a decrease of pCO2 by 18 μatm relative to surrounding waters. The other is a large‐scale variation (∼10.0° in latitude), with spatial gradient in pCO2 of up to 250 μatm. Detailed analyses show that the large‐scale variation is associated with diatom blooms, while the small‐scale variation is associated with coccolithophorid blooms with a calcification:photosynthesis = 1.0, and thus that seawater pCO2 is affected by the composition of marine ecosystems and its response to climate variability. SST rise also contributed to increased pCO2.
Mediterranean Sea level and barotropic flow through the Strait of Gibraltar for the period 1958–2001 and reconstructed since 1659
Authors: Gomis D. , Tsimplis M. N. , Martín‐Míguez B. , Ratsimandresy A. W. , García‐Lafuente J. , Josey S. A.
Published: November 2006

Sea level values from a two‐dimensional model of the Mediterranean Sea forced by atmospheric pressure and wind are used to estimate the barotropic flow through the Strait of Gibraltar for the period 1958–2001. The Mediterranean mean sea level derived from the model ranges between ±20 cm with a standard deviation of 5.5 cm and is correlated to the North Atlantic Oscillation (NAO) index. Thus NAO historical data and reconstructions are used to derive the Mediterranean Sea level variability from 1659 until 2001. The accuracy of the reconstruction is estimated in 2.7 cm for monthly mean values, 0.41 cm for annual mean values, and 0.22 cm for decadal mean values (0.48 cm for decadal winter mean sea level). The barotropic flow through the strait is computed from the model output as the time derivative of the total volume of the basin. During the period 1958–2001 the estimated daily flow ranges between ±2.7 Sv, with a standard deviation of 0.56 Sv. The dominant periodicities are in between 1 and 2 weeks. At these scales the model successfully reproduces previously published flow estimates based on current meter observations, which confirms that atmospheric pressure and wind dominate the intraseasonal variability of the flow. For the annual cycle the variability of the atmospherically induced flow is similar to the variability of the flow induced by the evaporation‐precipitation (E‐P) budget (±0.025 Sv), though absolute values of the first are about a third of the latter. At longer timescales the atmospheric contribution is much smaller than the E‐P induced flow.
Characterization of iron oxides in mineral dust aerosols: Implications for light absorption
Authors: Lafon Sandra , Sokolik Irina N. , Rajot Jean Louis , Caquineau Sandrine , Gaudichet Annie
Published: November 2006

We report on measurements that were specifically designed to determine iron oxides in mineral dust aerosols needed for improved optical modeling. Atmospheric dust samples as well as samples generated in a wind tunnel from soils were analyzed by a number of analytical techniques for their total and free iron content (bulk and size resolved), hematite and goethite, mineralogy, and size distribution. These samples are representative of several important dust sources in East Asia and northern Africa. A novel data set generated from these measurements enables us to perform an in‐depth modeling study of dust optical properties in the solar spectrum. We modeled the iron oxide–clay aggregates, which are the key light‐absorbing species, as well as their mixtures with nonabsorbing minerals. A volume fraction of iron oxide in aggregates was determined from measurements. Significant differences in the single‐scattering albedo, ω0, were found between hematite‐ and goethite‐clay aggregates, although these calculations involved several important assumptions about the partition of hematite and goethite in size‐resolved aggregates. Furthermore, we found that variability of the free iron content is large enough to cause important differences in ω0 of mineral dust originating from different sources. In contrast, this variability has little effect on the extinction coefficient and optical depth. We demonstrate that for the same size distribution, ω0 calculated from data obtained for Chinese and Tunisian samples show higher values and more distinct wavelength dependence than those of Niger dust. All the above ω0 differ from ones calculated using the refractive indices of Patterson et al. (1977) or the OPAC model (Hess et al., 1998), which are often used in radiative transfer studies. We conclude that information on a size‐resolved content of free iron and a fraction of hematite and goethite in aggregates will need to be known on a regional basis to improve the prediction of the single‐scattering albedo at solar wavelengths and hence the radiative impact of atmospheric mineral dust.
Storms in the ionosphere: Patterns and processes for total electron content
Authors: Mendillo Michael
Published: November 2006

The ionosphere's total electron content (TEC) is a parameter widely used in studies of the near‐Earth plasma environment. The scientific use of TEC appeared early in the artificial satellite era, and among its many contributions were fundamental insights into how the ionosphere responds to geomagnetic storms. While many excellent reviews of solar‐terrestrial disturbances exist in the literature, none have concentrated on the TEC parameter per se. With new TEC data sets increasingly available from the Global Positioning System (GPS), a comprehensive summary of pre‐GPS storm studies is needed to set the base for progress in the GPS era. This review summarizes past case studies, describes statistical occurrence pattern, and identifies responsible mechanisms validated via modeling. It presents a new set of results of TEC disturbance patterns during 180 geomagnetic storms to describe seasonal and solar cycle effects. It concludes with a set of open questions that require additional study.
Where are the hottest spots on Earth?
Authors: Mildrexler David J. , Zhao Maosheng , Running Steven W.
Published: November 2006

The location of the hottest spot on the Earth's surface has long been a source of interest and curiosity. With images of blazing desert landscapes, several places have proudly claimed the title of ‘hottest place on Earth.’ Death Valley, California, the hottest place in North America, held the world record air temperature of 56.7°C from 1913 to 1922, until the current world record air temperature of 58.0°C was recorded in 1922 in El Azizia, Libya. Until recently, only point‐based air temperature measurements in scattered locations were available to researchers trying to understand maximum temperatures. This incomplete picture, based largely on the locations of weather stations, clearly suggested that hotter air temperatures were occurring, but measurements on the scale needed to locate the hottest place simply were not practical.
Earthquake loss estimates in near real‐time
Authors: Wyss Max , Wang Rongjiang , Zschau Jochen , Xia Ye
Published: November 2006

The usefulness to rescue teams of nearreal‐time loss estimates after major earthquakes is advancing rapidly.The difference in the quality of data available in highly developed compared with developing countries dictates that different approaches be used to maximize mitigation efforts. In developed countries, extensive information from tax and insurance records, together with accurate census figures, furnish detailed data on the fragility of buildings and on the number of people at risk. For example, these data are exploited by the method to estimate losses used in the Hazards USMulfrHazard (HAZUSMH) software program (http://www.fema.gov/plan/prevent/hazus/). However, in developing countries, the population at risk is estimated from inferior data sources and the fragility of the building stock often is derived empirically, using past disastrous earthquakes for calibration [Wyss, 2004].
Land warming as part of global warming
Authors: Huang Shaopeng
Published: November 2006

The recent warming of Earth's surface is well documented in meteorological records. According to the World Meteorological Organization, the Earth's average surface air temperature (SAT) rose about 0.6°C in the twentieth century [Jones and Moberg,2003].

Any global scale variation in SAT is accompanied by variation of the thermal state of all major climate system components including the continental landmasses. Based on worldwide meteorological and borehole temperature records, this study suggests that the twentieth century global warming has deposited a large amount of thermal energy into the continental landmasses, and has resulted in an intensified heating of rocks underground. The feedback to the global climate system and the long‐term environmental consequences of the on‐going subsurface warming of the land remain to be recognized.
SABER temperature observations in the summer polar mesosphere and lower thermosphere: Importance of accounting for the CO2ν2 quanta V–V exchange
Authors: Kutepov Alexander A. , Feofilov Artem G. , Marshall Benjamin T. , Gordley Larry L. , Pesnell W. Dean , Goldberg Richard A. , Russell James M.
Published: November 2006

The polar summer thermal structure, with its cold mesopause and steep temperature gradients, both below and above the mesopause, produces the largest non‐LTE effects in the CO2ν2 mode manifold states. In this paper we focus on validating the non‐LTE model applied for operational temperature retrievals from the SABER 15 μm limb radiance observations for these extreme conditions. We demonstrate that accounting for the redistribution of ν2 quanta among various CO2 isotopes shifts the retrieved summer 2002 polar mesopause altitude upwards by 2 to 4 km. It brings the SABER temperature measurements into a better agreement with those of falling sphere experiments, lidar observations, as well as with climatological data.
Time‐frequency variability of Kuroshio meanders in Tokara Strait
Authors: Nakamura Hirohiko , Yamashiro Toru , Nishina Ayako , Ichikawa Hiroshi
Published: November 2006

The meander of the Kuroshio path, with periods of 30–90 days, dominates Tokara Strait, Japan. To understand the time‐frequency variability of this meander, two Kuroshio indicators were subjected to wavelet analysis for the period 1984–2004. The 30–90 day variance of the position of the Kuroshio in Tokara Strait shows a season‐fixed nature, with larger amplitudes in the period December–July. The amplitude of the variance in this phenomenon is also modulated by interannual variations, with small variance recorded during 1989–1992, large variance during 1993–1998, and a return to small variance from 1999–2003. This interannual variation is positively correlated with that of Kuroshio volume transport in Tokara Strait. The largest variance during February–April precedes the largest volume transport in April–May by about 1 month, suggesting that mesoscale menders are the forcing of the volume transport increase, not the other way around.
Symmetry and stability of the geomagnetic field
Authors: Coe R. S. , Glatzmaier G. A.
Published: November 2006

Computer simulations of the geodynamo reveal a strong inverse correlation between stability and equatorial symmetry of the simulated field. This result is consistent with the paleomagnetically inferred degree of symmetry of Earth's magnetic field during the past 150 Ma, which reversed polarity more frequently when it was more symmetrical. A geodynamo simulation with solid inner core much smaller than it is today produced an exceptionally antisymmetric field, raising the possibility that reversals may have been much less common in the distant geologic past than more recently. Paleomagnetic evidence suggests that this might well be true.
Dynamics of thin current sheets associated with magnetotail reconnection
Authors: Nakamura R. , Baumjohann W. , Asano Y. , Runov A. , Balogh A. , Owen C. J. , Fazakerley A. N. , Fujimoto M. , Klecker B. , Rème H.
Published: November 2006

We have examined the detailed structure of thin current sheets and their evolution during a substorm interval on 24 August 2003, when Cluster experienced several rapid current sheet crossings within a couple of ion gyrotimes. These crossings took place during an interval of high‐speed ion flows with BZ reversals and signatures of accelerated electrons, suggesting crossing of the reconnection region. On the basis of four‐point observations with a tetrahedron scale of ∼200 km, we could quantify for the first time the thickness of the current sheet, which was comparable to or less than one ion inertia length, and resolve some internal structures such as multiple peaks within these thin current sheets. Different patterns in jX and in electron anisotropy were identified during the current sheet crossings: two crossings during tailward flow interval exhibited a quadrupole‐type Hall current in the ion diffusion region without a guide field, while one crossing during earthward flow showed a current system as predicted in the ion diffusion region under the presence of a guide field. Multiple flux rope type signatures or transient skewed structures are observed in the thin current sheets, particularly in regions where signatures of electron acceleration are observed. These observations suggest that three‐dimensional localized/transient structures could play an essential role in the dynamics of the thin current sheets, while a gross X‐line picture can be established only in an average sense.
Cosmic ray induced ionization in the atmosphere: Full modeling and practical applications
Authors: Usoskin Ilya G. , Kovaltsov Gennady A.
Published: November 2006

We present a physical model to calculate cosmic ray induced ionization in the atmosphere. The model is based on the Monte Carlo CORSIKA tool, which simulates full development of an electromagnetic‐muon‐nucleonic cascade in the atmosphere, with the FLUKA package used for low‐energy interactions. The direct ionization by primary cosmic rays is explicitly taken into account. The model is applicable to the entire atmosphere, from the ground up to the stratosphere. A comparison to fragmentary direct measurements of the ionization in the atmosphere confirms the validity of the model in the whole range of geographical latitudes and altitudes. Results of the full Monte Carlo simulation are tabulated in a form of the ionization yield function. These tables are given together with a detailed recipe, which allows a user to compute easily the cosmic ray induced ionization for given location, altitude and the spectrum of cosmic rays. This provides a new tool for a quantitative study of the space weather influence upon the Earth's environment. Some practical applications are discussed.