bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blasenaufstieg an geneigter Wand in Wasser und Flüssigmetall mit Magnetfeld
Authors: Kaiser E. 
Published: May 2006

AbstractDer Blasenaufstieg in geneigten Rohren, mit Flüssigmetall (vergleichsweise mit Wasser) gefüllt, wird anhand von außen gemessener Blasenfrequenzen und ‐geschwindigkeiten als eine elementare Zweiphasenströmung untersucht. Nach den Ergebnissen wird in Flüssigmetall mit einem DC‐Magnetfeld die Blasengeschwindigkeit entgegen dem senkrechten Rohr eindeutig vermindert und damit die Verweilzeit steuerbar. Die Blasen werden gestaucht.
Einfache Methode zur Bestimmung von Fluidströmen
Authors: Mitrovic J. 
Published: May 2006

AbstractVorgestellt wird eine einfache Methode zur Bestimmung von Massenströmen flüssiger Fluide. Sie beruht auf der Messung des hydrostatischen Druckes und der Massenbilanz eines Systems mit einem Flüssigkeitszulauf. Diese Messmethode kann durch eine Ergänzung zur Ermittlung des Volumenstroms angewandt werden.
Kontrollierte Wasserstoffoxidation in einem mikrostrukturierten Mischer‐Reaktormodul
Authors: Görke O. , Pfeifer P. , Schubert K. 
Published: May 2006

AbstractFür die heterogen‐katalysierte Wasserstoffoxidation wird ein Mikrostrukturreaktor konzipiert, der Misch‐, Reaktions‐ und Wärmeübertragungseigenschaften vereinigt und mit dessen Hilfe es möglich ist, Wasserstoff kontrolliert zu oxidieren. Dieser Typus eines Mikrostrukturapparats kann bei geeigneter Variation der Außenmaße und der Überströmöffnungen der Reaktionspartner so angepasst werden, dass viele denkbare Gasphasen‐Reaktionen thermisch miteinander gekoppelt werden können. So können exotherme und endotherme Reaktionen auch bei stark unterschiedlichen Kinetiken der zu koppelnden Reaktionen energetisch ausgenutzt werden.
A Joint Experimental and Computational Study on the Electronic Communication in Diethynylaryl‐Bridged (η5‐C5H5)Fe(η2‐dppe) and (η5‐C5H5)Fe(CO)2 Units
Authors: Medei Laura , Orian Laura , Semeikin Oleg V. , Peterleitner Mikhail G. , Ustynyuk Nikolai A. , Santi Saverio , Durante Christian , Ricci Antonella , Lo Sterzo Claudio 
Published: May 2006

AbstractA family of bimetallic complexes [Cp(CO)2Fe–C≡C–Ar–C≡C–Fe(CO)2Cp] {Cp = C5H5; 6a–g: Ar = C4H2S (a), 3‐(C4H9)‐C4HS (b), 3‐(C16H33)‐C4HS (c), C6H4 (d), 2,5‐bis(OC4H9)‐C6H2 (e), 2,5‐bis(OC8H17)‐C6H2 (f), (C6H4)2 (g)} was prepared by the three‐step Pd‐catalysed extended one‐pot (EOP) synthetic protocol from Bu3Sn–C≡CH, X–Ar–X (X = I, Br) and Cp(CO)2FeI. Complexes 6a,d,g were then exposed to ultraviolet irradiation in the presence of an equivalent amount of 1,2‐bis(diphenylphosphanyl)ethane (dppe) to form the corresponding bimetallic complexes [Cp(dppe)Fe–C≡C–Ar–C≡C–Fe(dppe)Cp] (7a,d,g). Compounds 6a–g and 7a,d,g were characterised by cyclic voltammetry (CV). The most significant electrochemical information comes from the oxidation of the dppe derivatives. The ΔE° separations between the subsequent reversible waves suggest that the efficiency of the metal–metal electronic coupling decreases in the order 7a > 7d > 7g. Complexes 7a and 7g were also chemically oxidised with [Fe(Cp*)]2[BF4] {Cp* = C5(CH3)5} and [Fe(Cp)]2[BF4] respectively, and the near infrared (NIR) spectra of the mixed‐valence species 7a+ and 7g+ were recorded. A strong intervalence transition (IT) band was observed only for the radical cation 7a+. While this finding confirms the existence of an electronic interaction between the two termini when a 2,5‐thiophene group is present in the spacer, the NIR spectrum of 7g+ reveals a reduced efficiency in conveying electrons when the C4H2S moiety is replaced by a 4,4′‐biphenyl. In order to rationalise and quantify the extent of electronic communication, ruled by geometrical and electronic factors, density functional computational results on selected [Cp (PH3)2Fe] and [Cp(CO)2Fe] binuclear model complexes are reported. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Oxovanadium(IV) Complexes with Pyrazinecarboxylic Acids:The Coordinating Properties of Ligands with the (Naromatic, COO–) Donor Set
Authors: Garribba Eugenio , Micera Giovanni , Lodyga‐Chruscinska Elzbieta , Sanna Daniele 
Published: May 2006

AbstractComplex formation between the VIVO ion and four pyrazine derivatives, 2‐pyrazinecarboxylic acid (pzc), 5‐methyl‐2‐pyrazinecarboxylic acid (5‐Mepzc), 2,3‐pyrazinedicarboxylic acid (3‐COOHpzc) and 5‐hydroxy‐2‐pyrazinecarboxylic acid (5‐OHpzc), was studied in aqueous solution and in the solid state through the combined application of potentiometric and spectroscopic (EPR and FT‐IR) techniques. The results indicate that in acidic and neutral aqueous solution all theligands form mono(chelated), bis(chelated) and dinuclear species of composition VOL, VOL2 and (VO)2L2H–2. Hexacoordinated VOL2 complexes are characterised by a cis/trans isomerism, where cis and trans are the species with a water molecule bound in the cis or trans position with respect to the V=O group. The trans arrangement is favoured over the cis arrangement. Three solid derivatives, [VO(5‐Mepzc)2] (1), cis‐[VO(pzc)2(H2O)] (2) and cis‐[VO(3‐COOHpzc)2(H2O)] (3), were isolated and characterised. Based on the experimental results and on the data in the literature, the stability of cis and trans isomers in aqueous solution and in the solid state has been discussed, showing that with ligands of comparable basicity and size of the chelate ring the hydrophilicity favours the cis species and determines the relative amount of the two isomers. The analysis of the magnetic properties of the hydroxo‐bridged VIVO dimers suggests that for the (VO)2L2H–2 species the anti‐coplanar arrangement is realised. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Hydrolysis Rate of Functionalized Fullerenes Bearing Alkoxysilanes: A Comparative Study
Authors: Bianco Alberto , Maggini Michele , Nogarole Marco , Scorrano Gianfranco 
Published: May 2006

AbstractSoluble fulleropyrrolidines bearing a trialkoxysilyl functionality (methoxy, ethoxy, butoxy, and isopropoxy) have been prepared and characterized. The hydrolysis rate constant for each fulleropyrrolidine was measured with 1H NMR spectroscopy by following the disappearance of selected resonances of the fullerene substrate under the conditions (HCl/H2O/THF) used for the preparation of fullerene‐doped sol–gel glasses. It has been found that fulleropyrrolidine 1, bearing the trimethoxysilyl group, hydrolyzes faster than substrates 2–7 and should be the reagent of choice to minimize aggregation of the fullerene spheroid in sol–gel glassy matrices. The triethoxysilyl derivative 2, our benchmark fulleropyrrolidine for incorporation in sol–gel glasses, has the secondfastest hydrolysis rate. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Voltammetric Behavior of Arsenic(III) in the Presence of Sodium Diethyl Dithiocarbamate and Its Determination in Water and Highly Saline Samples by Adsorptive Stripping Voltammetry
Authors: de Carvalho Leandro M. , do Nascimento Paulo C. , Bohrer Denise , Pilau Eduardo J. , Stefanello Raquel , Lauer Markus 
Published: May 2006

AbstractThis paper describes the voltammetric behavior of As(III) at the hanging mercury drop electrode (HMDE) in the presence of sodium diethyl dithiocarbamate (SDDC) and a new voltammetric method for the determination of As(III) at trace levels. The method is based on the adsorptive deposition of a As(III) complex with SDDC at −0.45 V (vs. Ag/AgCl) on the HMDE in acidic medium of 0.01 mol L−1 HCl (pH 2.0) and its cathodic stripping during the potential scan (100 mV s−1). The linear range for the determination of As(III) in the presence of SDDC (4 μmol L−1) in water samples was between 1 and 10 μg L−1 for a deposition time of 300 s (r=0.994) and between 10 and 100 μg L−1 for a deposition time of 60 s (r=0.999). For the determination of As(III) in dialysis concentrate samples, the linear range was between 5 and 25 μg L−1 for a deposition time of 180 s (r=0.992) and between 10 and 100 μg L−1 for a deposition time of 60 s (r=0.996). Detection limits of 0.3 and 2.2 μg L−1 in water and dialysis concentrate samples were calculated for the method using a deposition time of 300 and 180 s, respectively. Recovery values between 93.0 and 110.0% for As(III) added to deionized, mineral, seawater (synthetic and real) and dialysis concentrate samples prove the satisfactory accuracy and applicability of the procedure.
Estimation of episodic exfoliation rates of rock sheets on a granite dome in Korea from cosmogenic nuclide analysis
Authors: Wakasa Sachi , Matsuzaki Hiroyuki , Tanaka Yukiya , Matsukura Yukinori 
Published: May 2006

AbstractWe have measured concentrations of cosmogenic 10Be and 26Al produced in situ at bare bedrock surfaces of successive sheets developing on a granite dome in Korea and calculated the exfoliation rate of sheeting joints. The exfoliation rate was obtained using a simple model in which the sheeting joints experience intermittent denudation, i.e. peeling off along the bedrock face. We find that the average exfoliation (erosion) rate of the episodic peeling‐off process is 5·6 cm/ka−1. The analysis is useful for understanding the evolution of granite sheeting structures on this dome in Korea. Copyright © 2006 John Wiley & Sons, Ltd.
Nonparametric linkage analysis using person‐specific covariates
Authors: Whittemore Alice S. , Halpern Jerry 
Published: May 2006

AbstractLinkage analysis provides an important tool for mapping genes for complex disease. However its usefulness has been limited by inadequate marker density, inadequate sample sizes and the possibility that different genes account for different subtypes of the disease (phenotypic heterogeneity). The first two limitations can be addressed by high‐density single nucleotide polymorphism (SNP) genotyping and the pooling of large sets of multiple‐case families. Phenotypic heterogeneity can be addressed by analyses that weigh the contributions of affected family members according to characteristics of their disease phenotypes. Here we introduce a method for including such person‐specific weights in nonparametric linkage analysis. We show with simulations that such weighting can provide stronger linkage signals when a causal polymorphism affects some manifestations of the disease more than others. We applied the method to prostate cancer linkage data in a region on chromosome 19p, and obtained higher lod scores by assigning weights of one to men with early‐onset aggressive cancers, weights of zero to those with late‐onset nonaggressive cancers, and intermediate weights to all other affected men. We have developed a modified version of GENEHUNTER that allows inclusion of person‐specific weights in the nonparametric analyses. This program is freely available at http://med.stanford.edu/epidemiology/statisticalSoftware/weightedKAC. Genet. Epidemiol. 2006. © 2006 Wiley‐Liss, Inc.
Omnibus permutation tests of the association of an ensemble of genetic markers with disease in case‐control studies
Authors: Potter Douglas M. 
Published: May 2006

AbstractAn omnibus permutation test of the overall null hypothesis can be used to assess the association of an entire ensemble of genetic markers with disease in case‐control studies. In this approach, p‐values for univariate marker‐specific Armitage trend tests are combined to form a scalar statistic, which is then used in a permutation test to determine an overall p‐value. Two previously described competing methods utilize either a standard two‐sample Hotelling's T2 statistic or a global U statistic that is a weighted sum of univariate U statistics. In contrast to Hotelling's test, omnibus tests are much less sensitive to missing data, and utilize all available data. In contrast to the global U test, omnibus tests do not require that the direction of the effects of the individual markers on the risk of disease be correctly specified in advance; in fact, any combination of one‐ and two‐sided univariate tests can be used. Simulations show that, even under circumstances favoring the competing tests (no missing data; direction of effects known), omnibus permutation tests based on Fisher's combining function or the Anderson‐Darling statistic typically have power comparable to or greater than Hotelling's and the global U tests. Genet. Epidemiol. 2006. © 2006 Wiley‐Liss, Inc.
Variance component models for X‐linked QTLs
Authors: Lange Kenneth , Sobel Eric 
Published: May 2006

AbstractThis paper discusses the theory and implementation of a model for mapping X‐linked quantitative trait loci (QTL). As a result of X inactivation, a female's body is subdivided into a number of patches. In each patch one of her two X chromosomes is randomly switched off. This smooths the allelic contributions in a heterozygote and implies that females should show less trait variation than males for an X‐linked trait. The latest version of the genetic analysis program Mendel incorporates a simple variance component version of this model. An application to head circumference in autistic children illustrates Mendel in action. Genet. Epidemiol. 2006. © 2006 Wiley‐Liss, Inc.
Fractal dimension in human cortical surface: Multiple regression analysis with cortical thickness, sulcal depth, and folding area
Authors: Im Kiho , Lee Jong‐Min , Yoon Uicheul , Shin Yong‐Wook , Hong Soon Beom , Kim In Young , Kwon Jun Soo , Kim Sun I. 
Published: May 2006

AbstractFractal dimension (FD) has been widely used to provide a quantitative description of structural complexity in the cerebral cortex. FD is an extremely compact measure of shape complexity, condensing all details into a single numeric value. We interpreted the variation of the FD in the cortical surface of normal controls through multiple regression analysis with cortical thickness, sulcal depth, and folding area related to cortical complexity. We used a cortical surface showing a reliable representation of folded gyri and manually parcellated it into frontal, parietal, temporal, and occipital regions for regional analysis. In both hemispheres the mean cortical thickness and folding area showed significant combination effects on cortical complexity and accounted for about 50% of its variance. The folding area was significant in accounting for the FD of the cortical surface, with positive coefficients in both hemispheres and several lobe regions, while sulcal depth was significant only in the left temporal region. The results may suggest that human cortex develops a complex structure through the thinning of cortical thickness and by increasing the frequency of folds and the convolution of gyral shape rather than by deepening sulcal regions. Through correlation analysis of FD with IQ and the number of years of education, the results showed that a complex shape of the cortical surface has a significant relationship with intelligence and education. Our findings may indicate the structural characteristics that are revealed in the cerebral cortex when the FD in human brain is increased, and provide important information about brain development. Hum Brain Mapp, 2006. © 2006 Wiley‐Liss, Inc.
Calibration of BOLD fMRI using breath holding reduces group variance during a cognitive task
Authors: Thomason Moriah E. , Foland Lara C. , Glover Gary H. 
Published: May 2006

AbstractThe proportionality of blood oxygen level‐dependent (BOLD) response during a cognitive task and that from a hypercapnic challenge was investigated in cortical structures involved in working memory (WM). Breath holding (BH) following inspiration was used to induce a BOLD response characteristic of regional vasomotor reactivity but devoid of metabolic changes. BOLD effects measured during BH were used to normalize individual subject activations during WM, which effectively reduced the confounding influence of individual‐ and region‐specific differences in hemodynamic responsivity common to both tasks. In a study of seven subjects, the BH calibration reduced intersubject variability in WM effect amplitude by 24.8% (P < 0.03). Reduced intersubject variability resulted in a 23.7% increase in group WM activation voxel extent significant at P < 0.001, with further increases at more stringent thresholds. Because the BH task does not require CO2 inhalation or other invasive manipulations and is broadly applicable across cortical regions, the proposed approach is simple to implement and may be beneficial for use not only in quantitative group fMRI analyses, but also for multicenter and longitudinal studies. Hum Brain Mapp, 2007. © 2006 Wiley‐Liss, Inc.
The vascular endothelial growth factor receptor (VEGFR‐1) supports growth and survival of human breast carcinoma
Authors: Wu Yan , Hooper Andrea T. , Zhong Zhaojing , Witte Larry , Bohlen Peter , Rafii Shahin , Hicklin Daniel J. 
Published: May 2006

AbstractVascular endothelial growth factor receptor 1 (VEGFR‐1) is present on endothelial cells and subsets of human tumor cells, raising the hypothesis that angiogenic factors may promote tumor growth both by inducing angiogenesis and directly signaling through activation of VEGFR‐1 on tumor cells. Here, we report that VEGFR‐1 is expressed on a panel of 16 human breast tumor cell lines, and the vasculature and the tumor cell compartment of a subset of breast carcinoma lesions, and that selective signaling through VEGFR‐1 on breast cancer cells supports tumor growth through downstream activation of the p44/42 mitogen‐activated protein kinase (MAPK) or Akt pathways. Ligand‐stimulated proliferation of breast tumor cells was inhibited by specific blockade with an anti‐VEGFR‐1 neutralizing monoclonal antibody. Treatment with anti‐VEGFR‐1 mAb significantly suppressed the growth of DU4475, MCF‐7, BT‐474 and MDA‐MB‐231 breast xenografts in athymic mice. Histological examination of anti‐VEGFR‐1 mAb treated tumor xenografts showed a significant reduction of activation of the p44/42 MAPK or Akt pathways in tumor cells resulting in an increase in tumor cell apoptosis. Importantly, cotreatment with mAbs targeting human VEGFR‐1 on tumor cells and murine VEGFR‐1 on vasculature led to more potent growth inhibition of breast tumor xenografts. The results suggest that VEGF receptors may not only modulate angiogenesis, but also directly influence the growth of VEGF receptor expressing tumors. © 2006 Wiley‐Liss, Inc.
Analysis of genes upregulated by the demethylating agent 5‐aza‐2′‐deoxycytidine in gastric cancer cell lines
Authors: Mikata Rintaro , Yokosuka Osamu , Fukai Kenichi , Imazeki Fumio , Arai Makoto , Tada Motohisa , Kurihara Tomoko , Zhang Kaiyu , Kanda Tatsuo , Saisho Hiromitsu 
Published: May 2006

AbstractIn gastric cancer, increasing numbers of genes have been reported to be silenced by aberrant methylation. However, global analysis of epigenetic inactivation in cancer cells has rarely been performed. For screening the genes upregulated by the demethylating agent 5‐aza‐2′‐deoxycytidine (DAC), cDNA microarray analysis (AceGene®, containing 30,000 genes) was performed using gastric cancer cell lines (AGS, MKN74, MKN1, MKN45 and Kato3) treated with DAC. The candidate upregulated genes were confirmed by real‐time PCR, and the methylation status of 5′CpG islands was determined by bisulfite DNA sequencing or methylation‐specific PCR. Among the upregulated genes considered to have CpG island in their promoter regions, we selected 5 genes (BCL2L10, DKK1, DNAJD1, GAGED2 and NMU) that exhibited a greater than 3‐fold increase in at least 2 cell lines. Of these, we could determine the methylation status of 5′CpG islands of BCL2L10, DKK1 and DNAJD1. 5′CpG of BCL2L10 and DNAJD1 was hypermethylated in 4 of 5 gastric cancer cell lines, whereas 5′CpG of DKK1 was hypermethylated in only 1 cell line. MSP analysis for BCL2L10 revealed that the CpG island was demethylated after DAC treatment. In addition, we observed that overexpression of BCL2L10 could promote apoptosis and growth‐inhibitory effect in gastric cancer cell lines. In conclusion, some of the genes upregulated by DAC treatment may be transcriptionally repressed by promoter hypermethylation. These genes might be related to gastric carcinogenesis. In particular, the suppression of BCL2L10, which could induce apoptosis and inhibit proliferation of cancer cells, might be one of the underlying mechanisms for gastric carcinogenesis. © 2006 Wiley‐Liss, Inc.
Lactic acid: recent advances in products, processes and technologies — a review
Authors: Datta Rathin , Henry Michael 
Published: May 2006

AbstractLactic acid, the most widely occurring hydroxycarboxylic acid, is an enigmatic chemical. It was discovered a long time ago and its use in food preservation and processing and as a specialty chemical has grown over the years with current production of about 120 000 t yr−1. Its potential as a major chemical feedstock, derived from renewable carbohydrates by sustainable technologies, to make plastics, fibers, solvents and oxygenated chemicals, had also been recognized. Recently, new technologies have emerged that can overcome major barriers in separations and purification and processing. Advances in electrodialysis (ED) and bipolar membranes and one particular process configuration termed the ‘double ED’ process, a specific combination of desalting ED followed by ‘water‐splitting’ ED with bipolar membranes, has given very promising results, showing a strong potential for an efficient and economic process for recovery and purification of lactic acid without generating a salt waste. For the production of polymers, several advances in catalysts and process improvements have occurred in the technology to produce dilactide and its polymerization to produce plastics and fibers by Natureworks LLC, which is the leader in lactic polymer technology and markets. Other advances in esterification technology with pervaporation and development of biosolvent blends also have a high potential for ‘green’ solvents in many applications. Recently, a considerable amount of pioneering effort in technology, product development and commercialization has been expended by several companies. To overcome the barriers to replace long‐established petroleum‐derived products, further real support from consumer, regulatory and government organizations is also needed. Copyright © 2006 Society of Chemical Industry
New aqueous two‐phase systems based on poly(ethylene oxide sulfide) (PEOS) and potassium phosphate for the potential recovery of proteins
Authors: Hernandez‐Mireles Tanhia , Rito‐Palomares Marco 
Published: May 2006

AbstractA new aqueous two‐phase system (ATPS) based on a degradable polymer called poly(ethylene oxide sulfide) with a molecular weight of 33 000 g mol−1 (identified as PEOS‐12) and potassium phosphate was exploited for the potential recovery of proteins. An initial characterisation of the ATPS was achieved by the construction of a phase diagram for the PEOS‐12/phosphate system. The protein partitioning behaviour of lysozyme and bovine serum albumin (BSA), selected as single model proteins, and B‐phycoerythrin (BPE) produced by Porphyridium cruentum in the new ATPS under increasing tie line length (TLL) conditions at constant phase volume ratio (Vr) and system pH was investigated. Both single proteins partitioned in the new ATPS, initially exhibiting bottom phase preference; however, lysozyme changed phase preference when TLL was increased. Fractionation of a complex model (production of BPE by P. cruentum) using PEOS‐12/phosphate ATPS was performed to evaluate the potential protein recovery from fermentation broth or cell homogenate. The proposed new ATPS proved to be suitable for the potential recovery of BPE from crude extract of P. cruentum. In general, a system comprising Vr = 1.0, 18% (w/w) PEOS‐12, 8% (w/w) phosphate and 30% (w/w) TLL at pH 7.0 provided conditions to concentrate BPE into the bottom phase (i.e. partitioning behaviour of BPE; lnKBPE = −1.8) with a protein recovery of 84%. The findings reported here demonstrate the potential application of the new ATPS for the recovery of proteins from complex biological suspensions. Copyright © 2006 Society of Chemical Industry