bluuebunny/crossref_metadata_2025 huggingface dataset:
Tumor necrosis factor α blockers and malignancy in children: Forty‐eight cases reported to the food and drug administration
Authors: Diak Peter , Siegel Jeffrey , La Grenade Lois , Choi Lauren , Lemery Steven , McMahon Ann
Published: April 2010

Objective

Malignancies reported in children using tumor necrosis factor α (TNFα) blockers have raised concerns of a potential increased risk. This study was undertaken to investigate postmarketing reports of malignancy in children treated with TNF blockers.

Methods

The FDA's Adverse Event Reporting System was searched to identify malignancies associated with the use of infliximab, etanercept, and adalimumab in children in whom therapy was initiated between the ages of 0 and 18 years. The reporting rates for infliximab and etanercept were compared with the background rate of malignancy in the general pediatric population.

Results

Forty‐eight reports of malignancy in children were identified: 31 following infliximab use, 15 following etanercept use, and 2 following adalimumab use. Half of the malignancies reported were lymphomas and included both Hodgkin's and non‐Hodgkin's lymphoma. The remaining reported cases involved a variety of different malignancies including leukemia, melanoma, and solid organ cancers. The majority of the reported cases (88%) involved the concomitant use of other immunosuppressants. Reporting rates for malignancy showed that infliximab had a consistently higher reporting rate when compared with background rates in the general pediatric population for lymphomas and all malignancies. The reporting rates for etanercept were elevated above background for lymphomas and were on par with background for all malignancies.

Conclusion

There is evidence that treatment with TNF blockers in children may increase the risk of malignancy. However, the cases were confounded by the potential risk of malignancy associated with underlying illnesses and the use of concomitant immunosuppressants; therefore, a clear causal relationship could not be established.
Biofuels in China: past, present and future
Authors: Zhong Cheng , Cao Ying‐Xiu , Li Bing‐Zhi , Yuan Ying‐Jin
Published: April 2010

Energy security and environmental stress force China to seek and develop biofuels as a substitute of fossil energy. Meanwhile, China has great potential to provide a large quantity of feedstocks for biofuel production due to its vast amount of non‐food crops, such as tuberous crops, sweet sorghum, cellulosic biomass, and algae. Recently, the study and the industrial‐scale production of biofuels, particularly, fuel ethanol and biodiesel, have progressed remarkably in China as a result of government preferential policies and funding supports. We have briefly reviewed the historical development of biofuels in China with special emphasis on current feedstock utilization and process technology development. The bottlenecks of utilizing various feedstocks have also been analyzed and the prospects for future biofuel development in China have been explored. Biorefineries integrating reliable, low‐cost and sufficient non‐food feedstock supplies with highly efficient, environmentally friendly process technologies could sustain a bright future for biofuel development in China. Copyright © 2010 Society of Chemical Industry and John Wiley & Sons, Ltd
Evaluation of alternatives for human lysozyme purification from transgenic rice: Impact of phytic acid and buffer
Authors: Wilken Lisa R. , Nikolov Zivko L.
Published: April 2010

Producing economically competitive recombinant human lysozyme from transgenic rice demands an inexpensive purification process for nonpharmaceutical applications. Human lysozyme is a basic protein, and thus, cation exchange chromatography was the selected method for lysozyme purification. Similar to other protein production systems, the identification of critical impurities in the rice extract was important for the development of an efficient purification process. Previous adsorption data indicated that phytic acid was probably responsible for an unacceptably low cation exchange adsorption capacity. In this study, we confirm that reducing phytic acid concentration improves lysozyme binding capacity and investigate alternative process conditions that reduce phytic acid interference. Compared with the previous best process, the adsorption capacity of human lysozyme was increased from 8.6 to 19.7 mg/mL when rice extract was treated with phytase to degrade phytic acid. Using tris buffer to adjust pH 4.5 extract to pH 6 before adsorption reduced phytic acid interference by minimizing phytic acid‐lysozyme interactions, eliminated the need for phytase treatment, and increased the binding capacity to 25 mg/mL. Another method of reducing phytic acid concentration was to extract human lysozyme from rice flour at pH 10 with 50 mM NaCl in 50 mM sodium carbonate buffer. A similar binding capacity (25.5 mg/mL) was achieved from pH 10 extract that was clarified by acidic precipitation and adjusted to pH 6 for adsorption. Lysozyme purities ranged from 95 to 98% for all three processing methods. The tris‐mediated purification was the most efficient of the alternatives considered. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010
Effect of the usage of wikis on an educational context
Authors: Abreu Pedro , Castro Silva Daniel , Mendes Pedro , Vinhas Vasco
Published: April 2010

The use of wiki tools in personal and professional contexts has increased in the past years. This article provides an overview on recent developments of wiki technologies, and tries to determine their acceptance level in an academic environment. Also, suggestions are presented that may influence future developments in this area. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 646–653, 2012
Optical coefficient‐based multivariate calibration on near‐infrared spectroscopy
Authors: Shi Zhenqi , Cogdill Robert P. , Martens Harald , Anderson Carl A.
Published: April 2010

The time and expense of calibration development limit the feasibility of NIR spectroscopy for many industrial applications, with a major portion of the costs being related to creation of a sufficient set of calibration samples. Net analyte signal (NAS) and generalized least squares (GLS) pre‐processing have been proposed in the literature as methods to simplify multivariate calibration by reducing the quantity of calibration samples by orthogonalizing or shrinking interference signals. Synthetic calibration has also been reported as a method to combine interference signals with pure component spectra to generate virtual calibration models, thereby reducing the number of real calibration samples required. The goals of this paper were to (1) compare theoretical and practical differences between NAS and GLS pre‐processing and (2) explore the potential of simplified NIR calibrations, both empirical and synthetic, constructed using optical coefficient‐based signal processing on predicting chemical compositions of pharmaceutical powder mixtures. A reduced calibration dataset including only one pharmaceutical powder mixture composition and pure component spectra was used for both empirical and synthetic calibrations. Absorption and reduced scattering coefficients, obtained from spatially‐resolved spectroscopy, were used herein as interference signals in NAS/GLS pre‐processing for both calibrations. As a result, NAS and GLS were shown to be equivalent in both theoretical and practical senses. After optical coefficient‐based signal processing, simplified calibrations, both empirical and synthetic, were demonstrated to have similar model performance as generic pre‐processing methods such as SNV and derivative, while requiring fewer principal components and achieving a lower prediction error. Copyright © 2010 John Wiley & Sons, Ltd.
Computational performance and cross‐validation error precision of five PLS algorithms using designed and real data sets
Authors: Martins João Paulo A. , Teófilo Reinaldo F. , Ferreira Márcia M. C.
Published: April 2010

An evaluation of computational performance and precision regarding the cross‐validation error of five partial least squares (PLS) algorithms (NIPALS, modified NIPALS, Kernel, SIMPLS and bidiagonal PLS), available and widely used in the literature, is presented. When dealing with large data sets, computational time is an important issue, mainly in cross‐validation and variable selection. In the present paper, the PLS algorithms are compared in terms of the run time and the relative error in the precision obtained when performing leave‐one‐out cross‐validation using simulated and real data sets. The simulated data sets were investigated through factorial and Latin square experimental designs. The evaluations were based on the number of rows, the number of columns and the number of latent variables. With respect to their performance, the results for both simulated and real data sets have shown that the differences in run time are statistically different. PLS bidiagonal is the fastest algorithm, followed by Kernel and SIMPLS. Regarding cross‐validation error, all algorithms showed similar results. However, in some situations as, for example, when many latent variables were in question, discrepancies were observed, especially with respect to SIMPLS. Copyright © 2010 John Wiley & Sons, Ltd.
Red‐NIR Luminescent Hybrid Poly(methyl methacrylate) Containing Covalently Linked Octahedral Rhenium Metallic Clusters
Authors: Molard Yann , Dorson Frederick , Brylev Konstantin A. , Shestopalov Michael A. , Le Gal Yann , Cordier Stéphane , Mironov Yuri V. , Kitamura Noboru , Perrin Christiane
Published: April 2010

The embedding of functional inorganic entities into polymer matrices has become an intense field of investigation in which the main challenges are to keep the added value of the inorganic entities while preventing their self‐aggregation within the organic matrix. We present a simple way to obtain a homogeneous highly red‐NIR luminescent hybrid copolymer that contains covalently bonded nanometric‐sized {Re6} octahedral clusters. The [Re6Sei8(OH)a6]4− cluster complexes are primarily functionalized in two steps with tert‐butylpyridine (TBP) and methacrylic acid (MAC) to give neutral [Re6Se8(TBP)4(MAC)2] building blocks that are copolymerized with methyl methacrylate (MMA) either in solution or in bulk in the presence of azobisisobutyronitrile as an initiator. Several samples containing 0, 0.025, 0.05, and 0.1 wt % of functionalized {Re6} clusters were prepared. As the {Re6} cluster/MMA ratio is very low, the obtained copolymers keep the entire processability of pure poly(methyl methacrylate) (PMMA), as demonstrated by differential scanning calorimetry and thermogravimetric analysis. Voltammetric and luminescence studies also indicate that the intrinsic properties of the clusters are preserved within the polymer matrix. All the samples show a bright (emission quantum yield=0.07), broad, and structureless emission band, which extends from λ=600 nm to more than λ=950 nm, with the maximum wavelength centered around λem=710 nm either in solution or in the solid state. Moreover, the high stability of the incorporated inorganic phosphors prevents the material from photobleaching, and thus the luminescence properties are kept entirely even after nine months of ageing.
A Spirocyclohexyl Nitroxide Amino Acid Spin Label for Pulsed EPR Spectroscopy Distance Measurements
Authors: Rajca Andrzej , Kathirvelu Velavan , Roy Sandip K. , Pink Maren , Rajca Suchada , Sarkar Santanu , Eaton Sandra S. , Eaton Gareth R.
Published: April 2010

Site‐directed spin labeling and EPR spectroscopy offer accurate, sensitive tools for the characterization of structure and function of macromolecules and their assemblies. A new rigid spin label, spirocyclohexyl nitroxide α‐amino acid and its N‐(9‐fluorenylmethoxycarbonyl) derivative, have been synthesized, which exhibit slow enough spin‐echo dephasing to permit accurate distance measurements by pulsed EPR spectroscopy at temperatures up to 125 K in 1:1 water/glycerol and at higher temperatures in matrices with higher glass transition temperatures. Distance measurements in the liquid nitrogen temperature range are less expensive than those that require liquid helium, which will greatly facilitate applications of pulsed EPR spectroscopy to the study of structure and conformation of peptides and proteins.
Group 13 Ligand Supported Heavy‐Metal Complexes: First Structural Evidence for Gallium–Lead and Gallium–Mercury Bonds
Authors: Prabusankar Ganesan , Gemel Christian , Winter Manuela , Seidel Rüdiger W. , Fischer Roland A.
Published: April 2010

Heavy‐metal complexes of lead and mercury stabilized by Group 13 ligands were derived from the oxidative addition of Ga(ddp) (ddp=HC(CMeNC6H3‐2,6‐iPr2)2, 2‐diisopropylphenylamino‐4‐diisopropyl phenylimino‐2‐pentene) with corresponding metal precursors. The reaction of Me3PbCl and Ga(ddp) afforded compound [{(ddp)Ga(Cl)}PbMe3] (1) composed of GaPbIV bonds. In addition, the monomeric plumbylene‐type compound [{(ddp)Ga(OSO2CF3)}2Pb(thf)] (2 a) with an unsupported Ga‐PbII‐Ga linkage was obtained by the reaction of [Pb(OSO2CF3)3] with Ga(ddp) (2 equiv). Compound 2 a falls under the rare example of a discrete plumbylene‐type compound supported by a nonclassical ligand. Interesting structural changes were observed when [Pb(OSO2CF3)3]⋅2 H2O was treated with Ga(ddp) in a 1:2 ratio to yield [{(ddp)Ga(μ‐OSO2CF3)}2(OH2)Pb] (2 b) at below −10 °C. Compound 2 b consists of a bent Ga‐Pb‐Ga backbone with a bridging triflate group between the GaPb bond and a weakly interacting water molecule at the gallium center. Similarly, the reaction of mercury thiolate Hg(SC6F5) with Ga(ddp) (2 equiv) produced the bimetallic homoleptic compounds anti‐[{(ddp)Ga(SC6F5)}2Hg] (3 a) and gauche‐[{(ddp)Ga(SC6F5)}2Hg] (3 b), respectively, with a linear Ga‐Hg‐Ga linkage. Compounds 1–3 were structurally characterized and these are the first examples of compounds comprised of GaPbII, GaPbIV, and GaHg bonds.
Binuclear Terbium(III) Complex as a Probe for Tyrosine Phosphorylation
Authors: Akiba Hiroki , Sumaoka Jun , Komiyama Makoto
Published: April 2010

By using the luminescence from binuclear complexes of TbIII (Tb2‐L1 and Tb2‐L2), phosphorylated Tyr residue in peptides was selectively detected in neutral aqueous solutions. Neither the non‐phosphorylated Tyr, pSer, pThr, nor the other phosphate‐containing biomolecules tested affected the luminescence intensity to any notable extent. Upon the binding of the pTyr to these TbIII complexes, the luminescence from the metal ion was notably promoted, as the light energy absorbed by the benzene ring of pTyr is efficiently transferred to the TbIII center. The binding activity of the binuclear TbIII complexes towards pTyr is two orders of magnitude larger than that of the corresponding mononuclear complex. These binuclear complexes were successfully used for real‐time monitoring of enzymatic phosphorylation of a peptide by a tyrosine kinase.
Efficient Photoinduced Energy Transfer Mediated by Aromatic Homoconjugated Bridges
Authors: Osío Barcina José , Herrero‐García Noelia , Cucinotta Fabio , De Cola Luisa , Contreras‐Carballada Pablo , Williams Rene M. , Guerrero‐Martínez Andrés
Published: April 2010

A new donor–bridge–acceptor (D‐B‐A) dyad consisting of ruthenium(II) and iridium(III) species separated by an homoconjugated bridge derived from 7,7‐diphenylnorbornane [Ir‐Nor‐Ru]3+ has been synthesised. The photophysical and electrochemical properties of the heterodinuclear complex have been compared with those of the analogous homodinuclear complexes [Ru‐Nor‐Ru]4+ and [Ir‐Nor‐ Ir]2+ . Transient absorption spectra on the nanosecond and sub‐picosecond timescales show, for the first time, that an homoconjugated bridge can mediate efficiently in the photoinduced energy transfer from the iridium(III) to the ruthenium(II) centres according to a Dexter‐type mechanism.
Racemization of the gastrointestinal antisecretory chiral drug esomeprazole magnesium via the pyramidal inversion mechanism: A theoretical study
Authors: Marom Hili , Agranat Israel
Published: April 2010

The pyramidal inversion mechanisms of the 6‐methoxy and the 5‐methoxy tautomers of (S)‐omeprazole were studied, employing ab initio and DFT methods. The conformational space of the model molecule (S)‐2‐[(3‐methyl‐2‐pyridinyl)methyl]sulfinyl‐1H‐benzimidazole was calculated, with respect to rotations around single bonds, at the B3LYP/6‐311G(d,p) level. All of the resulting conformations were used as starting points for full optimizations of (S)‐omeprazole, at B3LYP/6‐31G(d), B3LYP/6‐311G(d,p), B3LYP/6‐311++G(d,p), B3LYP/6‐311G(2df,2pd), MP2/6‐31G(d), and MP2/6‐311G(d,p) levels. Four distinct pathways were found for enantiomerization via the pyramidal inversion mechanism for each of the tautomers of (S)‐omeprazole. Each transition state, in which the sulfur, the oxygen and the two carbon atoms connected directly to the sulfur are in one plane, connects two diastereomeric minima. The enantiomerization is completed by free rotation around the sulfur–methylene bond, and around the methylene–pyridine ring bond. The effective Gibbs' free energy barrier for racemization ΔG of the two tautomers of (S)‐omeprazole are 39.8 kcal/mol (5‐methoxy tautomer) and 40.0 kcal/mol (6‐methoxy tautomer), indicating that the enantiomers of omeprazole are stable at room temperature (in the gas phase). The 5‐methoxy tautomer of (S)‐omeprazole was found to be slightly more stable than the 6‐methoxy tautomer, in the gas phase. The energy barrier (ΔG‡) for the(S,M)
$ \rightleftharpoons $(S,P) diastereomerization of (S)‐omeprazole due to the rotation around the pyridine chiral axis was very low, 5.8 kcal/mole at B3LYP/6‐311G(d,p). Chirality 2010. © 2010 Wiley‐Liss, Inc.
Online coupling of enantioselective capillary gas chromatography with proton nuclear magnetic resonance spectroscopy
Authors: Kühnle Maximilian , Kreidler Diana , Holtin Karsten , Czesla Harri , Schuler Paul , Schurig Volker , Albert Klaus
Published: April 2010

The hyphenation of enantioselective capillary gas chromatography and mass spectrometry is not always sufficient to distinguish between structural isomers, thus requiring peak identification by NMR spectroscopy. Here the first online coupling of enantioselective capillary gas chromatography with proton nuclear resonance spectroscopy is described for the unfunctionalized chiral alkane 2,4‐dimethylhexane resolved on octakis(6‐O‐methyl‐2,3‐di‐O‐pentyl)‐γ‐cyclodextrin at 60°C. NMR allows constitutional and configurational isomers (diastereomers and enantiomers) to be distinguished. Enantiomers display identical spectra at different retention times, which enable an indirect identification of these unfunctionalized alkanes. The presented method is still at an early development stage, and will require instrumental optimization in the future. Chirality 2010. © 2010 Wiley‐Liss, Inc.
Recent advances in asymmetric oxidative coupling of 2‐naphthol and its derivatives
Authors: Wang Hui
Published: April 2010

The enantiomeric atropoisomers of 1,1′‐binaphthyl‐2,2′‐diol (BINOL) have become one of the most widely used chiral ligands and auxiliaries for asymmetric synthesis. This review provides an overview of enantioselective synthesis of optical active BINOLs by straightforward asymmetric oxidative coupling of identical 2‐naphthol and its substituted derivatives. Chirality 2010. © 2010 Wiley‐Liss, Inc.
A novel chiral aliphatic–aromatic diamine promoted direct, highly enantio‐ and diastereoselective Michael addition of cyclohexanone to nitroolefins under solvent‐free conditions
Authors: Miao Shifeng , Bai Jinjin , Yang Jin , Zhang Yawen
Published: April 2010

A series of new highly efficient chiral aliphatic–aromatic diamine catalysts have been designed and successfully applied to the asymmetric Michael addition of cyclohexanone with nitroolefins under solvent‐free conditions without any acidic additives. The desired adducts were obtained in high yields with excellent enantio‐ and diastereoselectivities of syn products (up to >99% ee, >99:1 dr). Chirality 2010. © 2010 Wiley‐Liss, Inc
“Can You See Atoms?” – A Reflection from Different Scientific Perspectives
Authors: Parchmann Ilka , Lienau Christoph , Klüner Thorsten , Drögemüller Sarah , Al‐Shamery Katharina
Published: April 2010

Dieser Beitrag erörtert die Frage, ob man „Atome sehen“ kann, unter chemisch‐physikalischer, aber auch unter erkenntnistheoretischer und fachdidaktischer Perspektive. Dabei wird auf verschiedenen Niveaustufen dargestellt, mit welchen Modellen man Techniken wie die Rastertunnelmikroskopie erklären kann, wo aber auch Grenzen der Darstellung und des Verstehens liegen können. Eine abschließende Reflexion erörtert die Verwendung von Modellen im Chemieunterricht und in der Lehrerbildung.
Alternative Concepts About Density
Authors: Grüß‐Niehaus Thomas , Schanze Sascha
Published: April 2010

Dichte ist eine Stoffeigenschaft und wird im Chemieanfangsunterricht zur Charakterisierung der Stoffe herangezogen. Oft liegt bereits aus dem Physikunterricht ein Verständnis über die Dichte homogener Körper als Quotient aus Masse und Volumen vor. Mit der Einführung eines Teilchenmodells besteht bei einer unreflektierten Verwendung der lebensweltlichen Vorstellung des „dicht‐aneinander‐gedrängt‐seins“ die Gefahr alternativer Konzepte, sodass zum Beispiel die Unlöslichkeit oder Nicht‐Mischbarkeit über die Dichte zu erklären versucht wird. Dieser Beitrag zeigt konkrete Beispiele dieser Problematik auf und plädiert für eine regelmäßige Thematisierung der Problematik im Unterricht.
1,25D3 Enhances antitumor activity of gemcitabine and cisplatin in human bladder cancer models
Authors: Ma Yingyu , Yu Wei‐Dong , Trump Donald L. , Johnson Candace S.
Published: April 2010

BACKGROUND:

1,25 dihydroxyvitamin D3 (1,25D3) potentiates the cytotoxic effects of several common chemotherapeutic agents. The combination of gemcitabine and cisplatin is a current standard chemotherapy regimen for bladder cancer. The authors investigated whether 1,25D3 could enhance the antitumor activity of gemcitabine and cisplatin in bladder cancer model systems.

METHODS:

Human bladder cancer T24 and UMUC3 cells were pretreated with 1,25D3 followed by gemcitabine and cisplatin. Apoptosis was assessed by annexin V staining. Caspase activation was examined by immunoblot analysis and substrate‐based caspase activity assay. The cytotoxic effects were examined by using 3‐(4,5‐Dimethyl‐2‐thiazolyl)‐2,5‐diphenyl‐2H‐tetrazolium bromide (MTT) and in vitro clonogenic assay. p73 protein levels were assessed by immunoblot analysis. Knockdown of p73 was achieved by siRNA. The in vivo antitumor activity was assessed by in vivo excision clonogenic assay and tumor regrowth delay in the T24 xenograft model.

RESULTS:

1,25D3 pretreatment enhanced gemcitabine and cisplatin‐induced apoptosis and the activities of caspases 8, 9, and 3 in T24 and UMUC3 cells. 1,25D3 synergistically reduced gemcitabine and cisplatin‐suppressed surviving fraction in T24 cells. 1,25D3, gemcitabine, or cisplatin induced p73 accumulation, which was enhanced by gemcitabine and cisplatin or 1,25D3 and gemcitabine and cisplatin. p73 expression was lower in human primary bladder tumor tissue compared with adjacent normal tissue. Knockdown of p73 increased clonogenic capacity of T24 cells treated with 1,25D3, gemcitabine and cisplatin, or 1,25D3 and gemcitabine and cisplatin. 1,25D3 and gemcitabine and cisplatin combination enhanced tumor regression compared with 1,25D3 or gemcitabine and cisplatin alone.

CONCLUSIONS:

1,25D3 potentiates gemcitabine and cisplatin‐mediated growth inhibition in human bladder cancer models in vitro and in vivo, which involves p73 induction and apoptosis. Cancer 2010; 116:3294‐303. © 2010 American Cancer Society.
Palliative radiotherapy tailored to life expectancy in end‐stage cancer patients
Authors: Gripp Stephan , Mjartan Sibylle , Boelke Edwin , Willers Reinhardt
Published: April 2010

BACKGROUND:

The purpose of the study was to investigate the adequacy of palliative radiation treatment in end‐stage cancer patients.

METHODS:

Of 216 patients referred for palliative radiotherapy, 33 died within 30 days and constitute the population of the study. Symptoms, Karnofsky Performance Status (KPS), laboratory tests, and survival estimates were obtained. Treatment course was evaluated by medical records. Univariate analyses were performed by using the 2‐sided chi‐square test. With significant variables, multiple regression analysis was performed.

RESULTS:

Median age was 65 years, and median survival was 15 days. Prevailing primary cancer types were lung (39%) and breast (18%). Metastases were present in 94% of patients, brain (36%), bone (24%) and lung (18%). In 91%, KPS was <50%. KPS, lactate dehydrogenase, dyspnea, leucocytosis, and brain metastases conveyed a poor prognosis. From 85 survival estimates, only 16% were correct, but 21% expected more than 6 months. Radiotherapy was delivered to 91% of patients. In 90% of radiation treatments, regimens of at least 30 Gy with fractions of 2‐3 Gy were applied. Half of the patients spent greater than 60% of their remaining lifespan on therapy. In only 58% of patients was radiotherapy completed. Progressive complaints were noted in 52% and palliation in 26%.

CONCLUSIONS:

Radiotherapy was not appropriately customized to these patients considering the median treatment time, which resembles the median survival time. About half of the patients did not benefit despite spending most of their remaining lives on therapy. Prolonged irradiation schedules probably reflect overly optimistic prognoses and unrealistic concerns about late radiation damage. Single‐fraction radiotherapy was too seldom used. Cancer 2010. © 2010 American Cancer Society.
Experimental determination of laws of color harmony. Part 5: The harmony content of the various hue triads
Authors: Nemcsics Antal
Published: April 2010

We, in 1956 the Department of Architecture at the Budapest University of Technology and Economics, decided to start an extensive color harmony experiment. The experimental work, the collation, and processing of the collected data, lasting 50 years, was completed in 2006. The experiments described in this article are based on earlier experimental results obtained from investigation into the harmony content of hue pairs. We then decided to search for a third hue, which in association with an existing pair, with high‐color harmony, forms a hue triad with high‐harmony content too. The compositions prepared for the experiment were composed in each case of three hues of four identical saturation but different brightness, forming a group of 12 colors. The color content of the compositions covered the color space uniformly. That was the first stage in the experiment, carried out with 60 compositions. In the second stage, we investigated the effect of the saturation content of the colors used in the composition, on the harmony content of the hue triads. For this experiment, we prepared 48 compositions. In these experiments, we applied the method of grading. We concluded that the level of the harmony content of the hue triads depends on the inclination between the hue planes in the Coloroid color space. We also concluded that to every hue, selected for starting point, six well‐definable groups of hues can be ordered from the Coloroid color space, from which color triads with high harmony content, can be selected. It showed conclusively that the saturation level of the individual members of the triads has a significant influence on their harmony content. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2011
Color heterogeneity in visual search
Authors: Monnier Patrick
Published: April 2010

Distractor color heterogeneity refers to a condition in which a target is presented among distractors of different chromaticities. In the present study, the amount distractor color heterogeneity was varied systematically to determine how efficiently the visual system processes displays composed of search elements of multiple colors. Distractor color heterogeneity was expressed by selecting distractor chromaticities from sectors of various angles in a cone‐based normalized color space. The generalizability of the measurements was tested using two different visual search paradigms. An accuracy search task was used in which the search displays were presented as brief flashes and the dependent variable was search accuracy. A latency search task was used in which the display presentation time was under the participant's control and the dependent variable was reaction time. Compared to a homogeneous condition with distractors of a single color, distractor color heterogeneity had a deleterious effect on search performance in both paradigms. In normalized units, the measurements were similar across participants, target chromaticities, and tasks, but the same measurements expressed in non‐normalized units showed clear and systematic individual differences. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2011
Caenorhabditis elegans as a model system to study intercompartmental proteostasis: Interrelation of mitochondrial function, longevity, and neurodegenerative diseases
Authors: Kirstein‐Miles Janine , Morimoto Richard I.
Published: April 2010

The protein quality control system, composed of molecular chaperones and proteases, is of vital importance for the maintenance and function of the proteome and the health of the cell. To achieve this, the cellular proteostasis network integrates the protein folding machinery across all compartments of the eukaryotic cell to enable efficient communication and coordinate a rapid response of folding capacity. Quality control in the mitochondria, however, differs from its cytosolic counterpart due to its prokaryotic origin, and is entirely encoded by the nuclear genome. The control and regulatory cross‐talk of mitochondrial function in cellular proteostasis is essential for cellular metabolism, organismal development, and lifespan. Consequently, mitochondrial dysfunction has dramatic effects on the development and progression of a number of neurodegenerative diseases, such as Friedreich's ataxia and Parkinson's disease. Studies using Caenorhabditis elegans as a model system have greatly contributed to our current knowledge of inter‐compartmental proteostasis on the cellular and organismal levels. Developmental Dynamics 239:1529–1538, 2010. © 2010 Wiley‐Liss, Inc.
Inducible lineage tracing of Pax7‐descendant cells reveals embryonic origin of adult satellite cells
Authors: Lepper Christoph , Fan Chen‐Ming
Published: April 2010

We have generated a mouse strain carrying a Cre‐ERT2 knock‐in allele at the Pax7 locus, the Pax7CE allele (Lepper et al., 2009, Nature 460:627–631). Combining Pax7CE and the R26RLacZ Cre reporter allele, here we describe temporal‐specific tamoxifen (tmx)‐inducible lineage tracing of embryonic Pax7‐expressing cells. In particular, we focus on the somitic lineage. Tmx‐inducible Cre activity directed by the Pax7CE allele is similar to the endogenous Pax7 expression pattern. The somitic Pax7‐expressing cells selectively marked at embryonic day 9.5 (E9.5) give rise to dorsal dermis and brown adipose tissue, in addition to dorsal aspects of trunk muscles and the diaphragm muscle. However, they do not contribute to ventral body wall and limb muscles. After E12.5, marked Pax7‐expressing cells become lineage restricted to muscles. Descendants of these early marked Pax7‐expressing cells begin to occupy sublaminal positions associated with the myofibers around E16.5, characteristic of embryonic satellite cells. Furthermore, they contribute to adult myofibers and regeneration competent satellite cells in the tibialis anterior muscle, providing evidence that some adult satellite cells are of embryonic origin. genesis 48:424–436, 2010. © 2010 Wiley‐Liss, Inc.
Analysis of a zebrafish behavioral mutant reveals a dominant mutation in atp2a1/SERCA1
Authors: Olson Bryan D. , Sgourdou Paraskevi , Downes Gerald B.
Published: April 2010

Zebrafish embryos demonstrate robust swimming behavior, which consists of smooth, alternating body bends. In contrast, several motility mutants have been identified that perform sustained, bilateral trunk muscle contractions which result in abnormal body shortening. Unlike most of these mutants, accordion (acc)dta5 demonstrates a semidominant effect: Heterozygotes exhibit a distinct but less severe phenotype than homozygotes. Using molecular‐genetic mapping and candidate gene analysis, we determined that accdta5 mutants harbor a novel mutation in atp2a1, which encodes SERCA1, a calcium pump important for muscle relaxation. Previous studies have shown that eight other acc alleles compromise SERCA1 function, but these alleles were all reported to be recessive. Quantitative behavioral assays, complementation testing, and analysis of molecular models all indicate that the accdta5 mutation diminishes SERCA1 function to a greater degree than other acc alleles through either haploinsufficient or dominant‐negative molecular mechanisms. Since mutation of human ATP2A1 results in Brody disease, an exercise‐induced impairment of muscle relaxation, accdta5 mutants may provide a particularly sensitive model of this disorder. genesis, 48:354–361, 2010. © 2010 Wiley‐Liss, Inc.
Numerical analysis of chaos synchronization in semiconductor lasers subject to a common drive signal
Authors: Oowada Isao , Yamamoto Toru , Uchida Atsushi , Yoshimori Shigeru , Yoshimura Kazuyuki , Muramatsu Jun , Goto Shin‐Itiro , Davis Peter
Published: April 2010

Chaos synchronization of two semiconductor lasers commonly driven by a chaotic semiconductor laser subject to optical feedback was observed. Strongly correlated chaos synchronization between the two response lasers was observed even when the correlation between the drive and response lasers was low. It is shown that the cross correlation between the two responses is larger than that between the drive and response lasers over a wide parameter region. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(5): 50–58, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10200
A study on adaptive notch filter using exponential all‐pass transfer function
Authors: Kobayashi Masaki , Wang Chi
Published: April 2010

We propose an adaptive notch filter that realizes the phase shift of the all‐pass filter by the expression of Fourier sine series. The method of controlling the weights of the all‐pass filter formed by IIR filters is well known. However, these adaptive notch filters have not been put to practical use due to the peculiar stability problems of IIR filters and the problem of determining the degree of the IIR filter. The proposed adaptive notch filter is always stable since the all‐pass filter is formed by exponential filters. Furthermore, the adaptive algorithm is a simple gradient‐based algorithm and convergence of weights is guaranteed. The degree of the all‐pass filter depends only on the required steepness of the elimination characteristic and does not depend on the number of narrowband signals that are to be eliminated. Furthermore, the proposed method is suitable for practical use because the elimination characteristic is hardly influenced by a broadband signal added to the narrowband signal. The analytical results and a rigorous verification of the above features by computer simulation are presented. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(5): 8–14, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10256
Analysis of structural deformation and vibration of a transformer core by using magnetic property of magnetostriction
Authors: Kitagawa Wataru , Ishihara Yoshiyuki , Todaka Toshiyuki , Nakasaka Akira
Published: April 2010

A technique for structural analysis of transformer cores in terms of magnetostriction is proposed. The magnetic flux density of each element is first calculated by the finite element method (FEM). Then the magnetostrictive force on each element is calculated from measurements. The magnetostriction is specified as the initial strain and is converted into the force on each node, and a structural analysis is performed. The advantage of specifying the magnetostriction as the initial strain is that it is possible to obtain the force at the location of each element as a vector. Modal analysis and frequency response analysis were also performed and it was shown that resonance is related to the magnetostrictive frequency and the natural mode. Thus, it becomes possible to forecast the frequency at which the core vibrates most strongly which makes the proposed technique of analysis is very useful. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 172(1): 19–26, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20947
A test method of a PEFC single cell with reference electrodes
Authors: Tsutsumi Yasuyuki , Ono Seiichirou , Eguchi Mika
Published: April 2010

A test method is proposed for obtaining correct polarization curves of PEFC single cells with reference electrodes, which in principle should have identical anode polarization curves for both H2/O2 and H2/Air. Measured anode polarization curves are usually linear to the current density but not ohmic. Leak current between cathode and reference electrode causes voltage shift on the anode polarization curve. In order to obtain the ohmic anode polarization, the measured anode polarization curve should be moved vertically up to overlap with the base point. Configuration of the electrode edge adjacent to the reference electrode gives a significant effect on the anode and cathode potential. Polarization of an electrode which is 0.5 mm nearer to the reference electrode than the other electrode does not include the ohmic loss of the membrane. Instead, polarization of the other electrode includes the ohmic loss of the membrane. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 172(1): 10–18, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20979
Photoactive Ternary Lanthanide‐Centered Hybrids with Schiff‐Base Functionalized Polysilsesquioxane Bridges and N‐Heterocyclic Ligands
Authors: Liu Jin‐Liang , Yan Bing , Guo Lei
Published: April 2010

This work focuses on the synthesis of a series of silica‐based organic–inorganic hybrid materials, containing different Schiff‐base organic compounds, through a covalent self‐assembly process. We first prepared three functional molecular bridges that can both coordinate to lanthanide ions (Eu3+ and Tb3+) and form inorganic Si–O–Si networks with tetraethoxysilane (TEOS) from cohydrolysis and copolycondensation processes. Meanwhile, we selected N‐heterocyclic ligands [1,10‐phenanthroline (Phen) and 2,2′‐bipyridine (Bipy)] as the second ligands to act as the main energy donor to absorb abundant energy in the UV/Vis region and to transfer the energy to the corresponding lanthanide ions to sensitize their emission. The introduction of the second ligand can also take the place of the coordinated H2O and thus reduce the quenching effect of the OH group. Measurements of the photoluminescent properties of these materials show that the ternary lanthanide/inorganic/organic hybrids present stronger luminescent intensities and higher emission quantum efficiencies. The resulting amorphous materials exhibit regular, uniform microstructures and no phase separation occured since the organic and inorganic compounds were covalently linked through Si–O bonds through a self‐assembly process.
Electrocatalytic Application of Girard's Reagent T to Simultaneous Determination of Furaldehydes in Pharmaceutical and Food Matrices by Highly Sensitive Voltammetric Methods
Authors: Shamsipur Mojtaba , Beigi Ali Akbar Miran , Teymouri Mohammad , Tash Shahram Abolhassan , Samimi Vahid
Published: April 2010

Sensitive and precise voltammetric methods for the determination of trace amounts of furaldehydes, mainly as furfural (F) and 5‐hydroxymethyl‐2‐furaldehyde (HMF), in foods, pharmaceutical and other matrices is described. Determination of total furaldehyde at <μg g−1 levels in alkaline buffered aqueous media was individually investigated. By the use of ordinary SWV and adsorptive square wave stripping voltammetry (Ad‐SWSV), the detection limits for determination of F and HMF found to be 400 and 10 ng g−1, respectively. At a 1.0 μg g−1 level of furfural in sample, the relative standard deviation (n=4) was 2.79%. The application of Ad‐SWSV to the determination of F and HMF, after their in situ derivatization with trimethylaminoacetohydrazide chloride (Girard's reagent T) at a static mercury drop electrode (SMDE) in NH3‐NH4Cl buffer of pH 9.5, resulted in a limit of detection of 10 ng g−1 for the resolved peaks of HMF and F. The results obtained by the proposed method for the real samples were compared with the corresponding results from UV‐spectrophotometry and HPLC experiments in various matrices.
Preparation and Properties of Mercury Film Electrodes on Solid Amalgam Surface
Authors: Yosypchuk Bogdan , Fojta Miroslav , Barek Jiří
Published: April 2010

A simple apparatus (electrolyzer) and a reliable procedure were developed for the preparation of mercury films of exactly defined thickness on a silver solid amalgam substrate. Constant concentration of Hg(II) in the electrolyzer is ensured by dissolution of an anode from silver paste amalgam. Small volume of electrolyte, which can be used repeatedly many times, and paste amalgam preventing the spillage of liquid mercury substantially decrease the danger of environmental contamination with mercury. Parameters and behavior of mercury film electrodes on silver solid amalgam substrate (MF‐AgSAE) were compared with polished silver solid amalgam electrode (p‐AgSAE) which does not contain liquid mercury, with mercury meniscus modified silver solid amalgam electrode (m‐AgSAE), and with hanging mercury drop electrode (HMDE). The height of anodic stripping voltammetric peaks divided by electrode area was highest for MF‐AgSAE and the width of those peaks, which determines the resolution of the method, was minimal at MF‐AgSAE. Available potential window of MF‐AgSAE in different supporting electrolytes is comparable with that of HMDE.
Mitochondrial dysfunction in neurodegenerative diseases and cancer
Authors: de Moura Michelle Barbi , dos Santos Lucas Santana , Van Houten Bennett
Published: April 2010

Mitochondria are important integrators of cellular function and therefore affect the homeostatic balance of the cell. Besides their important role in producing adenosine triphosphate through oxidative phosphorylation, mitochondria are involved in the control of cytosolic calcium concentration, metabolism of key cellular intermediates, and Fe/S cluster biogenesis and contributed to programmed cell death. Mitochondria are also one of the major cellular producers of reactive oxygen species (ROS). Several human pathologies, including neurodegenerative diseases and cancer, are associated with mitochondrial dysfunction and increased ROS damage. This article reviews how dysfunctional mitochondria contribute to Alzheimer's disease, Parkinson's disease, Huntington's disease, and several human cancers. Environ. Mol. Mutagen., 2010. © 2010 Wiley‐Liss, Inc.
Experimental characterization of the mechanism of perfluorocarboxylic acids' liver protein bioaccumulation: The key role of the neutral species
Authors: Woodcroft Mark W. , Ellis David A. , Rafferty Steven P. , Burns Darcy C. , March Raymond E. , Stock Naomi L. , Trumpour Kyle S. , Yee Janet , Munro Kim
Published: April 2010

Perfluorocarboxylic acids (PFCAs) of chain length greater than seven carbon atoms bioconcentrate in the livers of fish. However, a mechanistic cause for the empirically observed increase in the bioconcentration potential of PFCAs as a function of chain length has yet to be determined. To this end, recombinant rat liver fatty acid-binding protein (L-FABP) was purified, and its interaction with PFCAs was characterized in an aqueous system at pH 7.4. Relative binding affinities of L-FABP with PFCAs of carbon chain lengths of five to nine were established fluorimetrically. The energetics, mechanism, and stoichiometry of the interaction of perfluorooctanoic acid (PFOA) with L-FABP were examined further by isothermal titration calorimetry (ITC) and electrospray ionization combined with tandem mass spectrometry (ESI-MS/MS). Perfluorooctanoic acid was shown to bind to L-FABP with an affinity approximately an order of magnitude less than the natural ligand, oleic acid, and to have at least 3:1 PFOA:L-FABP stoichiometry. Two distinct modes of PFOA binding to L-FABP were observed by ESI-MS/MS analysis; in both cases, PFOA binds solely as the neutral species under typical physiological pH and aqueous concentrations of the anion. A comparison of their chemical and physical properties with other well-studied biologically relevant chemicals showed that accumulation of PFCAs in proteins as the neutral species is predictable. For example, the interaction of PFOA with L-FABP is almost identical to that of the acidic ionizing drugs ketolac, ibuprofen, and warfarin that show specificity to protein partitioning with a magnitude that is proportional to the KOW (octanol–water partitioning) of the neutral species. The experimental results suggest that routine pharmacochemical models may be applicable to predicting the protein-based bioaccumulation of long-chain PFCAs. Environ. Toxicol. Chem. 2010; 29:1669–1677. © 2010 SETAC
Noonan syndrome, the SOS1 gene and embryonal rhabdomyosarcoma
Authors: Jongmans Marjolijn C. J. , Hoogerbrugge Peter M. , Hilkens Linda , Flucke Uta , van der Burgt Ineke , Noordam Kees , Ruiterkamp‐Versteeg Martina , Yntema Helger G. , Nillesen Willy M. , Ligtenberg Marjolijn J. L. , van Kessel Ad Geurts , Kuiper Roland P. , Hoogerbrugge Nicoline
Published: April 2010

Noonan Syndrome (NS) is an autosomal dominant condition characterized by short stature, facial dysmorphisms, and congenital heart defects, and is caused by mutations in either PTPN11, KRAS, NRAS, SHOC2, RAF1, or SOS1. Furthermore, NS is known for its predisposition to develop cancer, particularly hematological malignancies and specific solid tumors, mainly neuroblastoma and embryonal rhabdomyosacroma (ERMS). Until recently, however, cancer predisposition in NS patients with SOS1 mutations was not reported. Here we present a NS patient with a de novo germline SOS1 mutation (p.Lys728Ile) and ERMS. This heterozygous germline mutation was homozygously present in the ERMS of this patient due to an acquired uniparental disomy (UPD) of chromosome 2. In addition, several other chromosomal aberrations were encountered, some of which are known to recurrently occur in ERMS. Sequence analysis of the SOS1 gene in 20 sporadic ERMS tumors failed to reveal any pathogenic mutations, implicating that SOS1 is not a major player in the development of this tumor outside the context of NS. © 2010 Wiley‐Liss, Inc.