bluuebunny/crossref_metadata_2025 huggingface dataset:
Modular Synthesis of Functional Nanoscale Coordination Polymers
Authors: Lin Wenbin , Rieter William J. , Taylor Kathryn M. L.
Published: December 2008

The coordination‐directed assembly of metal ions and organic bridging ligands has afforded a variety of bulk‐scale hybrid materials with promising characteristics for a number of practical applications, such as gas storage and heterogeneous catalysis. Recently, so‐called coordination polymers have emerged as a new class of hybrid nanomaterials. Herein, we highlight advances in the syntheses of both amorphous and crystalline nanoscale coordination polymers. We also illustrate how scaling down these materials to the nano‐regime has enabled their use in a broad range of applications including catalysis, spin‐crossover, templating, biosensing, biomedical imaging, and anticancer drug delivery. These results underscore the exciting opportunities of developing next‐generation functional nanomaterials based on molecular components.
Single‐input and single‐output (SISO) controller reduction based on theL1‐norm
Authors: Yang Yu , Wu Jun , Xiong Rong , Xu Weihua , Chen Sheng
Published: December 2008

This paper proposes a new method to solve the controller‐reduction problem based on theL1‐norm. This method uses a reduced‐order closed‐loop system to deduce reduced‐order controllers. The problem of obtaining the required lower‐order closed‐loop system was formulated as anL1‐norm optimization, and the conditions were provided for guaranteeing the internal stability and the existence of lower‐order controllers from the obtained reduced‐order closed‐loop system. In addition, the particle swarm optimization and sequence linear programming were adopted to solve the resultantL1‐norm optimization. Two numerical examples demonstrated the effectiveness of the proposed method. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd.
Airborne remote sensing of valley floor geoarchaeology using Daedalus ATM and CASI
Authors: Challis Keith , Kincey Mark , Howard Andy J
Published: December 2008

This paper investigates the potential of multispectral methods of airborne remote sensing for geological and archaeological prospection in river valleys, specifically the archaeologically rich, well‐documented aggregate landscape of the middle Trent Valley in the East Midlands of England. The paper reviews the systematic examination of Daedalus 1268 Airborne Thematic Mapper (ATM) and Compact Airborne Spectrographic Imager (CASI) multispectral data. Data from a single flight along the Trent Valley in 1996 were subject to a comprehensive suit of analytical techniques including the calculation of vegetation indices and multivariate analysis. The results suggest that both ATM and CASI data have great potential for detecting and characterizing archaeological and geological features. Vegetation indices relying on ratios of red to infrared reflectance were particularly effective at highlighting cropmarks, in some cases revealing crop variation not apparent in the visible spectrum. Copyright © 2008 John Wiley & Sons, Ltd.
A Retrospective on the Design and Synthesis of Novel Molecules through a Strategic Consideration of Metathesis and Suzuki–Miyaura Cross‐Coupling
Authors: Kotha Sambasivarao , Mandal Kalyaneswar
Published: December 2008

Synergy in synthesis: Strategic consideration of metathesis and Suzuki–Miyaura (SM) cross‐coupling for CC bond‐formation processes has opened up new and “green” synthetic routes to various complex targets. The use of this synergistic combination for the synthesis of supramolecular ligands, polyaromatic compounds, and complex natural products is covered in this Focus Review.

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In recent years, ruthenium‐catalyzed metathesis and palladium‐catalyzed Suzuki–Miyaura cross‐coupling reactions have proven to be the most efficient tools for carbon–carbon bond formation in synthetic organic chemistry. This is mainly because of the stability and remarkable functional‐group tolerance of these catalysts. Therefore, the strategic consideration of these two powerful reactions can eventually minimize the synthetic steps for the construction of complex target molecules. In this perspective we summarize the efforts of many research groups who have used the combination of these two powerful reactions (either together in concert or separated by a few multistep sequences) for the synthesis of supramolecular ligands, polyaromatic compounds, and complex natural products.
Single and Double CCl‐Activation of Methylene Chloride by P,N‐ligand Coordinated Rhodium Complexes
Authors: Blank Benoît , Glatz Germund , Kempe Rhett
Published: December 2008

Two in one: The simultaneous formation of bimetallic μ‐methylene bridged RhIII complexes as well as dimeric RhIII complexes with terminal chloromethyl groups is observed for P,N‐ligand stabilized RhI complexes by CCl bond activation of methylene chloride. A mechanistic proposal for the formation of both activation products is also discussed.

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The synthesis of RhI complexes with P‐functionalized aminopyridine ligands is reported as well as the first simultaneous observation of a single and double activation of CCl bonds of methylene chloride affording both a dimeric RhIII complex bearing terminal CH2Cl groups in addition to a binuclear RhIII complex with a bridging μ‐CH2 group. The structures of the oxidative addition products were obtained by X‐ray diffraction studies and NMR experiments were performed to elucidate some aspects of the reaction pathway.
Magneto‐Structural Correlations in a 1,3,2‐Dithiazolyl Radical Crystal, BBDTA⋅GaBr4: Structure and Magnetic Properties of its Three Polymorphs
Authors: Fujita Wataru , Kikuchi Koichi
Published: December 2008

Three attractions in one cage: Various magnetic networks are formed in the three polymorphs of an organic magnet, BBTDA(=benzo[1,2‐d:4,5‐d′]bis[1,3,2]dithiazole)⋅GaBr4. The three phases show quite different magnetic behaviors in spite of having the same chemical formula. Their magnetic differences originate from the relative configuration of the neighboring organic radical molecules in their crystals.

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We investigate the preparation, crystal growth, crystal structure, and magnetic properties of the three polymorphs (α, β, and γ) of an organic magnet, BBDTA(=benzo[1,2‐d:4,5‐d′] bis[1,3,2]dithiazole)⋅GaBr4, which is an S‐1/2 system. In the α phase, BBDTA+ units form a square‐planar lattice, and show canted antiferromagnetism with a magnetic coupling constant J/kB of −18 K and a canting angle of 0.15° below 15.5 K. The β phase is composed of a ferromagnetic regular chain with a J/kB value of +4.5 K and a strong antiferromagnetic chain with J/kB=−99 K, and shows ferromagnetic ordering in spins of purely the ferromagnetic chain below 0.4 K. The γ phase is isostructural with γ‐BBDTA⋅GaCl4, which is an organic ferromagnet below 7.0 K, and possesses antiferromagnetic interactions of J/kB=−60 K between BBDTA+ cations, and shows no magnetic ordering until 2 K. The magnetic properties of these phases are quite sensitive to the molecular alignment in the crystals.
Point and Interval Estimation of the Population Size Using a Zero‐Truncated Negative Binomial Regression Model
Authors: Cruyff Maarten J. L. F. , van der Heijden Peter G. M.
Published: December 2008

This paper presents the zero‐truncated negative binomial regression model to estimate the population size in the presence of a single registration file. The model is an alternative to the zero‐truncated Poisson regression model and it may be useful if the data are overdispersed due to unobserved heterogeneity. Horvitz–Thompson point and interval estimates for the population size are derived, and the performance of these estimators is evaluated in a simulation study. To illustrate the model, the size of the population of opiate users in the city of Rotterdam is estimated. In comparison to the Poisson model, the zero‐truncated negative binomial regression model fits these data better and yields a substantially higher population size estimate. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Comparison of Population Size Estimators under the Truncated Count Model With and Without Allowance for Contaminations
Authors: Viwatwongkasem Chukiat , Kuhnert Ronny , Satitvipawee Pratana
Published: December 2008

The purpose of the study is to estimate the population size under a homogeneous truncated count model and under model contaminations via the Horvitz‐Thompson approach on the basis of a count capture‐recapture experiment. The proposed estimator is based on a mixture of zero‐truncated Poisson distributions. The benefit of using the proposed model is statistical inference of the long‐tailed or skewed distributions and the concavity of the likelihood function with strong results available on the nonparametric maximum likelihood estimator (NPMLE). The results of comparisons, for finding the appropriate estimator among McKendrick's, Mantel‐Haenszel's, Zelterman's, Chao's, the maximum likelihood, and the proposed methods in a simulation study, reveal that under model contaminations the proposed estimator provides the best choice according to its smallest bias and smallest mean square error for a situation of sufficiently large population sizes and the further results show that the proposed estimator performs well even for a homogeneous situation. The empirical examples, containing the cholera epidemic in India based on homogeneity and the heroin user data in Bangkok 2002 based on heterogeneity, are fitted with an excellent goodness‐of‐fit of the models and the confidence interval estimations may also be of considerable interest. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the role of protein structural dynamics in the catalytic activity and thermostability of serine protease subtilisin Carlsberg
Authors: Pagán Miraida , Solá Ricardo J. , Griebenow Kai
Published: December 2008

The effect of structural dynamics on enzyme activity and thermostability has thus far only been investigated in detail for the serine protease α‐chymotrypsin (for a recent review see Solá et al., Cell Mol Life Sci 2007, 64(16): 2133–2152). Herein, we extend this type of study to a structurally unrelated serine protease, specifically, subtilisin Carlsberg. The protease was incrementally glycosylated with chemically activated lactose to obtain various subtilisin glycoconjugates which were biophysically characterized. Near UV‐CD spectroscopy revealed that the tertiary structure was unaffected by the glycosylation procedure. H/D exchange FT‐IR spectroscopy was performed to assess the changes in structural dynamics of the enzyme. It was found that increasing the level of glycosylation caused a linearly dependent reduction in structural dynamics. This led to an increase in thermostability and a decrease in the catalytic turnover rate for both, the enzyme acylation and deacylation steps. These results highlight the possibility that a structural dynamics—activity relationship might be a phenomenon generally found in serine proteases. Biotechnol. Bioeng. 2009;103: 77–84. © 2008 Wiley Periodicals, Inc.
Biofilm monitoring on rotating discs by image analysis
Authors: Pons Marie‐Noëlle , Milferstedt Kim , Morgenroth Eberhard
Published: December 2008

The macrostructure development of biofilms grown in a lab‐scale rotating biological contactor was monitored by analyzing the average opacity and the texture of gray‐level images of the discs. The reactor was fed with municipal or synthetic wastewater. Experiments lasted on average 4–14 weeks. The images were obtained with a flat‐bed scanner. The opacity and its standard deviation are directly extracted from the annular zone where the biofilm develops. This zone is defined by the outer edge of the disc and the waterline. The spatial gray‐level dependence matrix (SGLDM) approach was used for the texture assessment. As this method requires rectangular images, a geometrical transformation had to be developed to transform the ring into a workable area. This transformation now allows quantitative image analysis on circular biofilms. As a last step, Principal Components Analysis was applied to the set of textural descriptors to reduce the number of textural parameters. Opacity and textural information allowed the non‐intrusive monitoring of the growth/regrowth of the biofilms as well as biofilm loss, due to detachment, auto‐digestion, or protozoan grazing. Textural description was very valuable by helping to discriminate biofilms of similar opacity characteristics but presenting different macrostructures. Biotechnol. Bioeng. 2009;103: 105–116. © 2008 Wiley Periodicals, Inc.
Modern cross‐linking strategies for synthesizing acellular hemoglobin‐based oxygen carriers
Authors: Harris David Raphael , Palmer Andre Francis
Published: December 2008

Unmodified cell‐free hemoglobin (Hb) is structurally unstable when transfused into the blood stream (Valeri et al., Artif Cells Blood Substit Immobil Biotechnol. 2000;28:451‐475; Chan et al., Toxicol Pathol. 2000;28:635‐642; Eike, Dissertation, 2005; Eike and Palmer, Biotechnol Prog. 2004;20:946‐952). This review examines some of the latest chemical strategies used over the last 5 years to intra‐ and intermolecularly cross‐link Hb, thereby stabilizing its quaternary structure. Therefore, this work will address the following aspects: (1) site‐specific chemical modifications of Hb and (2) non‐site‐specific chemical modifications of Hb, including, but not limited to, PolyHeme®, Hemopure®, Oxyglobin®, and SOD‐Hb. Current strategies for synthesizing PEGylated Hb is outside the scope of this review and will not be discussed herein. For a more thorough review of PEGylated Hb, the reader is directed to the following works: Cabrales and Friedman, Transfus Alternatives in Transfus Med. 2007;9:281–293 and Winslow, Biochim Biophys Acta, 2008;1784(10):1382–1386.
Surface‐Induced Regulation of Podosome Organization and Dynamics in Cultured Osteoclasts
Authors: Geblinger Dafna , Geiger Benjamin , Addadi Lia
Published: December 2008

Bone is continuously repaired and remodeled through the well‐coordinated activity of osteoblasts, which form new bone, and osteoclasts, which resorb it. How osteoclasts sense the properties of the bone surface remains unclear. By combining light and electron microscopy, we compared osteoclast behavior on three distinct surfaces: glass, calcite single crystals, and bone. Podosomes, the basic units of the adhesion structure, and their organization into superstructures were found to be common to cells that were attached to all three substrates, whereas the structure of the resorption organelle, the so‐called “ruffled border,” markedly differed. Moreover, the integrity, stability, and dynamic behavior of the adhesion superstructures also fundamentally differed, depending on the substrate. We conclude that osteoclasts sense the local properties of the underlying substrate and respond to these signals, both locally and globally.
Utilization of Evaporation during the Crystallization Process: Self‐Templation of Organic Parallelogrammatic Pipes
Authors: Seo Myungeun , Kim Jung Hak , Seo Gon , Shin Chae‐Ho , Kim Sang Youl
Published: December 2008

Analogues of 4‐dodecyloxy‐2‐trifluoromethylbenzamide (12FH2) consisting of a hydrophobic alkyl chain, a trifluoromethylated aromatic ring, and a self‐complementary hydrogen‐bonding amido group were synthesized, and the structural effect of each component on the formation of parallelogrammatic pipes was investigated. Differential scanning calorimetry and powder XRD analyses revealed that all‐trans L and gauche‐rich S polymorphic forms appeared for the analogues with more than eight carbon atoms in the alkyl chain, that is, the polymorphism originates in the conformation of the alkyl groups and hydrogen‐bonding patterns of the benzamide group. Also, the trifluoromethyl substituent is crucial in that it provides an appropriate molecular balance between the benzamide and alkyl groups. Scanning electron microscopy and powder XRD analyses of solids obtained by a drying‐mediated assembly process revealed that production of the L polymorph by polymorphic transition from the S polymorph resulted in evolution of a three‐dimensional structure when the alkyl group has more than 12 carbon atoms. Among the series of compounds, 12FH2 and 4‐tetradecyloxy‐2‐trifluoromethylbenzamide (14FH2) formed parallelogrammatic pipes with micrometer dimensions. An atomic force microscopy study of 12FH2 suggested that a single pipe may be composed of platelike crystallites of L polymorph. From a mercury‐intrusion porosimetry study, it was determined that macroporous materials with average pore diameters of about 40 μm and porosity of about 80 % were obtained. The previously proposed self‐templation mechanism by polymorphic transition from S to L polymorph was further discussed in view of polymorphism and the crystallization rate. An appropriate molecular balance between the benzamide and alkyl groups is necessary to induce a proper polymorphic transition for the development of a three‐dimensional hollow structure in the evaporation process.
Photochemical Regulation of an Artificial Hydrolase by a Backbone Incorporated Tertiary Structure Switch
Authors: Lindgren N. Johan V. , Varedian Miranda , Gogoll Adolf
Published: December 2008

A stilbene chromophore has been incorporated into the turn region of a 42 amino acid peptide, linking two helical peptide sections. Spatial proximity between these sections, as well as aggregation into dimers, is required to facilitate the catalytic function of this artificial hydrolase. Photomodulation of the hydrolase activity results in an increase of the activity of 42 % upon switching from the trans to the cis isomer of the chromophore. This is rationalized by a change in the aggregation state of the peptidomimetic, which is supported by diffusion coefficients obtained from PFG‐NMR experiments. The results show that incorporation of a small, relatively flexible chromophore into a large peptide is capable of inducing a considerable change in tertiary structure and thus, functionality.
Structural Analysis of Zincocenes with Substituted Cyclopentadienyl Rings
Authors: Fernández Rafael , Grirrane Abdessamad , Resa Irene , Rodríguez Amor , Carmona Ernesto , Álvarez Eleuterio , Gutiérrez‐Puebla Enrique , Monge Ángeles , López del Amo Juan Miguel , Limbach Hans‐Heinrich , Lledós Agustí , Maseras Feliu , del Río Diego
Published: December 2008

New zincocenes [ZnCp′2] (2–5) with substituted cyclopentadienyl ligands C5Me4H, C5Me4tBu, C5Me4SiMe2tBu and C5Me4SiMe3, respectively, have been prepared by the reaction of ZnCl2 with the appropriate Cp′‐transfer reagent. For a comparative structural study, the known [Zn(C5H4SiMe3)2] (1), has also been investigated, along with the mixed‐ring zincocenes [Zn(C5Me5)(C5Me4SiMe3)] (6) and [Zn(C5Me5)(C5H4SiMe3)] (7), the last two obtained by conproportionation of [Zn(C5Me5)2] with 5 or 1, as appropriate. All new compounds were characterised by NMR spectroscopy, and by X‐ray methods, with the exception of 7, which yields a side‐product (C) upon attempted crystallisation. Compounds 5 and 6 were also investigated by 13C CPMAS NMR spectroscopy. Zincocenes 1 and 2 have infinite chain structures with bridging Cp′ ligands, while 3 and 4 exhibit slipped‐sandwich geometries. Compounds 5 and 6 have rigid, η5/η1(σ) structures, in which the monohapto C5Me4SiMe3 ligand is bound to zinc through the silyl‐bearing carbon atom, forming a ZnC bond of comparable strength to the ZnMe bond in ZnMe2. Zincocene 5 has dynamic behaviour in solution, but a rigid η5/η1(σ) structure in the solid state, as revealed by 13C CPMAS NMR studies, whereas for 6 the different nature of the Cp′ ligands and of the ring substituents of the η1‐Cp′ group (Me and SiMe3) have permitted observation for the first time of the rigid η5/η1 solution structure. Iminoacyl compounds of composition [Zn(η5‐C5Me4R)(η1‐C(NXyl)C5Me4R)] resulting from the reactions of some of the above zincocenes and CNXyl (Xyl=2,6‐dimethylphenylisocyanide) have also been obtained and characterised.
Grün fluoreszierendes Protein: unschätzbares Werkzeug der Zellforscher
Authors: Welter Kira
Published: December 2008

Die Verwendung fluoreszierender Proteine zur Untersuchung von chemischen Prozessen in lebenden Zellen ist heute eine Standardmethode in der Biologie und der medizinischen Forschung. Damit können Wissenschaftler neue Einblicke in die molekularen Dimensionen des Lebens gewinnen und Prozesse wie etwa die Ausbreitung von Krebszellen oder die Arbeitsweise von Nervenzellen im Gehirn in Echtzeit untersuchen. Das grün fluoreszierende Protein (GFP) hat bei der Entwicklung dieser wertvollen Technik eine Pionierrolle gespielt. Für die Entdeckung und Weiterentwicklung des GFP teilen sich in diesem Jahr der Japaner Osamu Shimomura und die beiden US‐Amerikaner Martin Chalfie und Roger Y. Tsien den Nobelpreis für Chemie.
A simple PWM method for improving lamp current crest factor of valley‐filled electronic ballast
Authors: Lee Zhi‐Ren , Hsiao Horng‐Ching
Published: December 2008

In this paper, a PWM method to improve the lamp current crest factor (CCF) of the valley‐filled electronic ballast (VFEB) is presented. The VFEB has merits of high power factor, simple structure, and low cost. However, it results in an excessive CCF, which will shorten the lifetime of low‐pressure discharge lamp. The proposed method controls switching duty ratio by feeding forward the dc‐link voltage waveform of VFEB. It decreased the duty ratio with rising of dc‐link voltage. Therefore, the proposed method could restrain the lamp peak current and improve the lamp CCF. The control block diagram and basic theory are introduced to improve the CCF. The computer simulations verify the proposed method and derive a minimum lamp CCF. The experimental results demonstrate that the lamp CCF was reduced from 1.9 to 1.58, the ac line power factor is 96%, and the input current THD is 29.3%. The fixed switching frequency operation gains a satisfactory power quality. Copyright © 2008 John Wiley & Sons, Ltd.
Serum homocysteine, folate, vitamin B12 levels and arterial stiffness in diabetic patients: which of them is really important in atherogenesis?
Authors: Shargorodsky M. , Boaz M. , Pasternak S. , Hanah R. , Matas Z. , Fux A. , Beigel Y. , Mashavi M.
Published: December 2008

Aim

Hyperhomocystinaemia is associated with macro‐ and microangiopathic diabetic complications. However, the role of homocysteine (Hcy), serum folate, and vitamin B12 level in the development of premature vascular damage in type 2 diabetic patients is not clear. The present study was designed to assess the relationship between total Hcy, folate, and vitamin B12 levels and arterial stiffness, an early marker of generalized atherosclerosis.

Methods

As many as 86 subjects with type 2 diabetes mellitus were studied. All participants were evaluated for glucose, HbA1C, lipid profile, hs‐CRP, endothelin, Hcy, vitamin B12, and folate. Pulse wave velocity (PWV) and augmentation index (AI) were performed as a non‐invasive recording and computer analysis of the two artery sites pressure waveform using SphygmoCor (version 7.1, AtCor Medical, Sydney, Australia).

Results

Hcy was significantly positively associated with age, serum creatinine, and vitamin B12 levels. No association between Hcy and folate was observed. The Hcy concentration was significantly positively associated with PWV (r = 0.540, p < 0.0001) and AI (r = 0.390, p < 0.0001). In a general linear model of PWV, Hcy emerged as an independent predictor of PWV even after controlling for age, creatinine, vitamin B12, and folate levels. In a multiple linear regression analysis, the association between Hcy and arterial stiffness was independent of traditional cardiovascular risk factors. Vitamin B12 levels were significantly inversely associated with tHcy (r = − 0.263, p = 0.015) and marginally associated with PWV(r = − 0.212, p = 0.052). Significant associations between folate levels and PWV were not detected.

Conclusions

The results lend support to the hypothesis that elevated Hcy may have a key role in the development of atherogenesis in diabetic patients. Additionally, vitamin B12 is significantly associated with tHcy concentrations and is identified as a marginally independent correlate of PWV in diabetic patients in the absence of folate deficiency. Copyright © 2008 John Wiley & Sons, Ltd.
Proneural gene ash1 promotes amacrine cell production in the chick retina
Authors: Mao Weiming , Yan Run‐Tao , Wang Shu‐Zhen
Published: December 2008

The diverse types of neurons and Müller glia in the vertebrate retina are believed to arise from common progenitor cells. To better understand how neural diversity is achieved during retinal neurogenesis, we examined the function of ash1, a proneural bHLH gene expressed in progenitor cells throughout retinal neurogenesis. Published studies using retinal explant culture derived from knockout mice concluded that ash1 is required for the production of late‐born neurons, including bipolar cells. In this study, gain‐of‐function experiments were carried out in ovo in embryonic chick retina. In the developing chick retina, expression of ash1 temporally overlapped with, but spatially differed from, the expression of ngn2, also a proneural gene expressed in progenitor cells throughout retinal neurogenesis. Retrovirus‐driven overexpression of ash1 in the developing chick retina decreased the progenitor population (BrdU+ or expressing ngn2), expanded the amacrine population (AP2α+ or Pax6+), and reduced bipolar (chx10 mRNA+) and Müller glial (vimentin+) populations. Photoreceptor deficiency occurred after the completion of neurogenesis. The number of ganglion cells, which are born first during retinal neurogenesis, remained unchanged. Similar overexpression of ngn2 did not produce discernible changes in retinal neurogenesis, nor in ash1 expression. These results suggest that ash1 promotes the production of amacrine cells and thus may participate in a regulatory network governing neural diversity in the chick retina. © 2008 Wiley Periodicals, Inc. Develop Neurobiol, 2009
Image contrast enhancement based on differential gray level of gradient pixel pairs
Authors: Saitoh Fumihiko
Published: December 2008

This paper proposes a method for image contrast enhancement by using not only the distribution of gray levels but also the spatial features included in an objective input image. A contour appears on the boundary between two planes that have different gray levels. For image contrast enhancement, expanding the difference of the gray levels in the planes located on both sides of the contour is assumed to be effective. By expanding the subtraction between the gray levels in the neighboring planes, the contour becomes visually conspicuous. Therefore, the difference between the gray levels of the pixel pair is treated as the weight for contrast enhancement in the proposed method. The resultant images obtained by the proposed method had better contrast and less noise than those obtained by the conventional methods. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(7): 1–9, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10014
Ultrasonic diagnosis of cirrhosis based on preprocessing using pyramid recurrent neural network
Authors: Lu Jianming , Liu Jiang , Zhao Xueqin , Yahagi Takashi
Published: December 2008

In this paper, a pyramid recurrent neural network is applied to characterize the hepatic parenchymal diseases in ultrasonic B‐scan texture. The cirrhotic parenchymal diseases are classified into four types according to the size of hypoechoic nodular lesions. The B‐mode patterns are wavelet transformed, and then the compressed data are fed into a pyramid neural network to diagnose the type of cirrhotic diseases. Compared with the three‐layer neural networks, the performance of the proposed pyramid recurrent neural network is improved by a more efficient utilization of lower layers. Simulation results show that the proposed system is suitable for diagnosis of cirrhosis diseases. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(7): 10–19, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10121
Epitaxial growth of WOx nanorods on single‐crystal tungsten substrate
Authors: Shingaya Yoshitaka , Nakayama Tomonobu
Published: December 2008

Nanorods of substoichiometric tungsten oxide (WOx) were grown on single‐crystal tungsten substrate. The grown nanorods were investigated with scanning electron microscopy and atomic force microscopy. WOx nanorods were grown on W(001) in accordance with epitaxial relationship between WO3 crystals and W(001) surface. The results indicate that the WO3 crystals formed at the initial stage act as the nuclei of WOx nanorods. Nanorod growth of certain epitaxial directions can be selectively enhanced by choosing growth methods or choosing suitable crystallographic orientation of substrate surface. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(7): 20–24, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10122
Comparison of standard link color visibility between young adults and elderly adults
Authors: Saito Daisuke , Saito Keiichi , Notomi Kazuhiro , Saito Masao
Published: December 2008

The rapid dissemination of the World Wide Web raises the issue of Web accessibility, and one important aspect is the combination of foreground and background colors. In our previous study, the visibility of Web‐safe colors on a white background was examined, and the blue used for unvisited standard link colors was found to have high visibility for a wide range of ages. Since the use of blue and underlining are recommended for links, in this study we examine high‐visibility background colors for the unvisited standard link color, that is, blue. One hundred and twenty‐three background colors for blue were examined using the pair comparison method, and the relationship between visibility and color difference was discussed in the uniform CIELAB color space (L*a*b* color space). Effective background colors for the standard link color were determined in the CIELAB space, namely, L* larger than 68, a* smaller than 50, and b* larger than −50 provided high visibility for a wide range of ages. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(7): 41–47, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10126
Experimental study on improvement of transient stability with braking resistor
Authors: Iida Shinji , Imamura Shunji , Shirai Goro , Fujita Goro
Published: December 2008

The electric power industry has undergone considerable changes in the past decade throughout the world. The essential feature of these changes is to promote competition among utilities and to form active power market with reliable and less expensive electricity. Under these circumstances, stabilization and voltage stability problems of power systems are very important. Power systems engineers are examining the effect of the resistance value of braking resistors and the timing of their insertion on the improvement of the stability level.

In this paper, we report on experiments carried out on the optimal size and switching of braking resistors, shunt capacitors, and other auxiliary devices. The experimental system model consists of a single synchronous generator connected through two parallel transmission lines to an infinite bus. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(8): 11–19, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10130
Modeling of secondary arc on high‐voltage solar array in space
Authors: Cho Mengu
Published: December 2008

Secondary arc on solar arrays in space in defined as an arc discharge short‐circuiting adjacent solar cells. As the operational voltage of spacecraft increases to 100 V, there is more risk of secondary arc that can destroy solar array circuits. Secondary arc is categorized as a vacuum arc, although its current is very low, even less than 1 A. One‐dimensional modeling is carried out to derive sets of parameters that satisfy the governing equations. Genetic algorithm is used to find the optimal set of solutions. Even at a current less than 1 A, the solutions exist though the arc voltage is higher than the experimental values by several tens of volts. ©2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(4): 1– 8, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20571
A PAM control method for a matrix converter based on a virtual AC/DC/AC conversion method
Authors: Odaka Akihiro , Sato Ikuya , Ohguchi Hideki , Tamai Yasuhiro , Mine Hironori , Itoh Jun‐Ichi
Published: December 2008

In this paper, a novel control method for a matrix converter is proposed. The proposed method is a PAM (Pulse Amplitude Modulation) control method based on a virtual AC/DC/AC conversion method. Output voltage amplitude is controlled by controlling a virtual DC link voltage with a virtual rectifier. Output frequency is controlled by a virtual inverter.

First, the proposed method is explained. Next, the validity of the proposed method is confirmed through simulation and experiment using a 750‐W prototype matrix converter. Moreover, various characteristics of the proposed method and conventional virtual AC/DC/AC method are compared through experiment. As a result of the experiment, it has been understood that total harmonic distortion of output current and common‐mode voltage can be reduced compared with the case of using a conventional virtual AC/DC/AC conversion method. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(4): 88–96, 2009; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/eej.20601
Evaluation of the introduction of a micro‐cogeneration system into residential houses based on monitored daily‐basis energy demand data
Authors: Inada Ryo , Sugihara Hideharu , Saeki Osamu , Tsuji Kiichiro
Published: December 2008

In order to reduce CO2 emission from residential sectors in Japan, PEFC with high efficiency and low environmental impact is expected as one of the promising micro‐cogeneration (µCGS) systems. However, the energy demands in houses largely differ from each other and the profiles are also changed every day. Thus, when µCGS is actually introduced, it is necessary to examine the equipment capacity and operation of µCGS in each house. In this paper, the optimization model is developed in order to evaluate the µCGS based on daily‐basis demand data. Using actually monitored energy demand data in four households, the differences between using daily‐basis data and using the monthly‐average data are evaluated from viewpoints of economic and environmental performance of µCGS systems. Moreover, by adding the penalty factor to disposal heat of µCGS, it is seen that system configuration and system operation of µCGS can attain CO2 reduction and energy conservation as well as cost reduction. ©2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(4): 20–30, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20653
Syntheses, Structures, and Theoretical Studies of New Ternary Antimonides β‐RECoSb3 (RE = La–Nd, Sm)
Authors: Cai Wei‐Zhao , Wu Li‐Ming , Li Long‐Hua , Chen Ling
Published: December 2008

Five new intermetallic ternary cobalt antimonides β‐RECoSb3 have been prepared by solid state reactions and characterized by single‐crystal X‐ray diffraction. The title compounds crystallize in β‐RENiSb3‐type structure, Pbcm (No.57), Z = 8, with a = 12.985(4)–12.5530(13) Å, b = 6.1603(18)–6.1043(4) Å, c = 12.166(4)–12.0267(12) Å for RE = La, Ce, Pr, Nd, and Sm. Their structures feature the anionic Sb square nets and CoSb6 octahedron layers that are separated by RE3+ cations along the a axis. The structural relationship among parent‐type (RECrSb3), α‐type (RENiSb3), and β‐type (RECoSb3) has been presented. The electronic band structure of β‐LaCoSb3 has been calculated with the aid of the tight‐bonding linear muffin‐tin orbital (TB‐LMTO) method and the results suggest that the three types of RETSb3 are metallic in both b and c directions and the electrical conductivities along the a direction are relatively weak. The magnetic calculations indicated that the rare‐earth atoms would be the only source for the magnetic properties. Therefore, β‐type Co analogues should be magnetically identical to the corresponding Ni members. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Chemical composition of essential oils from aerial parts of Cinnamomum malabatrum (Burman f.) Bercht & Presl.
Authors: Leela N. K. , Vipin T. M. , Shafeekh K. M. , Priyanka V. , Rema J.
Published: December 2008

The constituents of the essential oils of leaf, petiole, shoot and terminal shoot of Cinnamomum malabatrum were determined by GC and GC–MS. Thirty‐nine compounds, constituting 95% of the oil, were identified in the leaves. Major constituents of the leaf oil were (E)‐caryophyllene (28.6%), (E)‐cinnamyl acetate (15.1%), bicyclogermacrene (14.4%) and benzyl benzoate (8.5%). Twenty‐eight compounds, representing 98% and 97% of the oil, were identified in the petioles and shoots, respectively, whereas in the oil of the terminal shoots 34 compounds, accounting for 97%, were identified. The essential oils of the petioles, shoots and terminal shoots were dominated by linalool (77.8−79.4%). This is the first report of the essential oil constituents of C. malabatrum. Copyright © 2008 John Wiley & Sons, Ltd.
Decimalization, ETFs and futures pricing efficiency
Authors: Chen Wei‐Peng , Chou Robin K. , Chung Huimin
Published: December 2008

This study investigates the impact of decimalization (penny pricing) on the arbitrage relationship between index exchange‐traded funds and E‐mini index futures. The empirical results reveal that subsequent to penny pricing, there is a significant fall in the mean ex ante arbitrage profit, especially in the cases with higher transaction costs. Using the ordinary least squares and quantile regressions to control for the influences of changes in other market characteristics, it is found that the overall pricing efficiency has deteriorated in the post‐decimalization period. These results are consistent with the hypothesis that, due to the lowered market depth and increased execution risks, the introduction of decimalization has in general resulted in weakening the ability and the willingness of arbitrageurs to initiate arbitrage trades, which subsequently leads to a reduction in the general efficiency of the cash/futures pricing system. © 2008 Wiley Periodicals, Inc. Jrl Fut Mark 29:157–178, 2009
Can structural MRI indices of cerebral integrity track cognitive trends in executive control function during normal maturation and adulthood?
Authors: Kochunov Peter , Robin Don A. , Royall Don R. , Coyle Thomas , Lancaster Jack , Kochunov Valeria , Schlosser Anita E. , Fox Peter T.
Published: December 2008

We explored the relationship between structural neuroimaging‐based indices of cerebral integrity and executive control function (ECF) in two groups of healthy subjects: A maturing group (33 subjects; 19–29 years) and a senescing group (38 adults; 30–90 years). ECF was assessed using the Executive Interview (EXIT) battery. Cortical indices of cerebral integrity included GM thickness, intergyral span, and sulcal span, each measured for five cortical regions per hemisphere. Subcortical indices included fractional anisotropy (FA), measured using track‐based‐spatial‐statistics (TBSS), and the volume of T2‐hyperintense WM (HWM). In the maturing group, no significant relationships between neuroanatomical changes and ECF were found; however, there were hints that late‐term maturation of cerebral WM influenced variability in ECF. In the senescing group, the decline in ECF corresponded to atrophic changes in cerebral WM (sulcal and intergyral span) primarily in the superior frontal and anterior cingulate regions. A large fraction of the variability in ECF (62%) can be explained by variability in the structural indices from these two regions. Hum Brain Mapp 2009. © 2008 Wiley‐Liss, Inc.
An early complement-dependent and TLR-4–independent phase in the pathogenesis of ethanol-induced liver injury in mice #
Authors: Roychowdhury Sanjoy , McMullen Megan R. , Pritchard Michele T. , Hise Amy G. , van Rooijen Nico , Medof Edward M. , Stavitsky Abram B. , Nagy Laura E.
Published: December 2008

The innate immune system has been implicated in the pathogenesis of alcoholic liver disease. Although innate immunity is usually considered an early response to injury, previous work implicating innate immunity in ethanol-induced liver injury focuses primarily on long-term ethanol exposure. We investigated the early period of ethanol exposure to determine whether there were temporal associations between activation of innate immune responses and known correlates of liver injury. Female C57BL/6 mice were allowed free access to an ethanol-containing Lieber-DeCarli diet or were pair-fed a control diet. Within 4 days of ethanol exposure, we observed a striking spike in expression of hepatic proinflammatory cytokines—including tumor necrosis factor α (TNF-α), interleukin-6, and interferon-γ—prior to hepatic triglyceride accumulation or increased plasma alanine aminotransferase activities, as well as before the induction of cytochrome P450 2E1 or oxidative stress. This early spike in inflammatory cytokines coincided with deposition of C3b-iC3b/C3c (C3b) in the liver. This deposition, resulting from the cleavage of the third component of the complement system (C3), is evidence for activation of complement in response to ethanol. C3
−/− mice were protected from the early, ethanol-induced increase in hepatic TNF-α expression. Ethanol increased C3b deposition in mice deficient in C3a receptor or C5a receptor, as well as in wild-type mice depleted of hepatic macrophages; however, there was no increase in hepatic TNF-α in the absence of C3a receptor, C5a receptor, or hepatic macrophages. In contrast, the absence of Toll-like receptor 4 (TLR-4) had no effect on the early, ethanol-induced increase in either C3b or TNF-α. Conclusion: We have identified a complement- and macrophage-dependent, but TLR-4 independent, phase in the pathogenesis of ethanol-induced liver injury. (Hepatology 2009.)
Dietary administration of the licorice flavonoid isoliquiritigenin deters the growth of MCF‐7 cells overexpressing aromatase
Authors: Ye Lan , Gho Wai M. , Chan Franky L. , Chen Shiuan , Leung Lai K.
Published: December 2008

Licorice is the sweet‐tasting rhizomes of a bean plant and is quite commonly used in Western countries for culinary purposes, while it is a medicinal herb in China. Many flavonoids have been isolated from licorice, and their pharmacological properties may be applicable in preventive medicine. Overexposure to estrogen has been implicated in the etiology of breast cancer, and cytochrome P450 (CYP) 19 enzyme, or aromatase, catalyzes the rate‐limiting reaction. Phytocompounds that are able to inhibit this enzyme may potentially suppress breast cancer development. In the present study the licorice flavonoid isoliquiritigenin (ILN) was shown to be an aromatase inhibitor in recombinant protein and MCF‐7 cells stably transfected with CYP19 (MCF‐7aro). ILN displayed a Ki value of around 3 μM, and it also blocked the MCF‐7aro cell growth pertaining to the enzyme activity in vitro. Subsequently, the compound administered in diet was given to ovariectomized athymic mice transplanted with MCF‐7aro cells. This mouse model is widely accepted for studying postmenopausal breast cancer. The phytochemical significantly deterred the xenograft growth without affecting the body weight. Subsequently, the flavonoid's effect on CYP19 transcriptional control in vitro was also investigated. At the mRNA level, ILN could also suppress the expression in wild‐type MCF‐7 cells. Reporter gene assay and real‐time PCR verified that the transactivity of CYP19 driven by promoters I.3 and II was suppressed in these cells. Deactivation of C/EBP could be the underlying molecular mechanism. Our study demonstrated that ILN was an inhibitor of aromatase and a potential chemopreventive agent against breast cancer. © 2008 Wiley‐Liss, Inc.
Inhibition of matrix metalloproteinase‐2 enhances radiosensitivity by abrogating radiation‐induced FoxM1‐mediated G2/M arrest in A549 lung cancer cells
Authors: Chetty Chandramu , Bhoopathi Praveen , Rao Jasti S. , Lakka Sajani S.
Published: December 2008

Matrix metalloproteinase‐2 (MMP‐2), is known to degrade the collagen IV, plays a role in radiation‐induced lung injury. We therefore investigated the antitumor effects of combining MMP‐2 inhibition using an adenovirus expressing siRNA against MMP‐2 (Ad‐MMP‐2‐Si) with radiation therapy (IR) on A549 lung cancer cells in vitro and in vivo. IR increased MMP‐2 mRNA, protein and activity in lung cancer cells. MMP‐2 inhibition along with IR enhanced radiosensitivity as determined by clonogenic assay, flow cytometry and TUNEL assay. We show that MMP‐2 inhibition prior to irradiation reduced p53 phosphorylation, with a corresponding reduction in the expression of the p53 downstream target gene p21Cip1/Waf1. Irradiated tumor cells induced the FoxM1‐mediated DNA repair gene, XRCC1 and Checkpoint kinases 2/1, which were abrogated with combined treatment of Ad‐MMP‐2‐Si and IR. Further, the combination of Ad‐MMP‐2‐Si with radiotherapy significantly increased antitumor efficacy in vivo compared to either agent alone. Indeed, histological analysis of tumor sections collected from the combination group revealed more apoptotic cells. These studies suggest that MMP‐2 inhibition in combination with radiotherapy abrogates G2 cell cycle arrest leading to apoptosis and provide evidence of the antitumor efficacy of combining MMP‐2 inhibition with irradiation as a new therapeutic strategy for the effective treatment of NSCLC patients. © 2008 Wiley‐Liss, Inc.
Doxorubicin and mitoxantrone drug eluting beads for the treatment of experimental peritoneal carcinomatosis in colorectal cancer
Authors: Keese Michael , Gasimova Lala , Schwenke Kay , Yagublu Vugar , Shang Edward , Faissner Ralf , Lewis Andrew , Samel Stefan , Löhr Matthias
Published: December 2008

We investigated the therapeutic efficiency of sulfonate‐modified polyvinyl alcohol beads loaded with doxorubicin, irinotecan or mitoxantrone in vitro and in vivo in a model of experimental peritoneal carcinomatosis (PC). In vitro, cell proliferation was efficiently impaired by doxorubicin drug eluting bead (DEB) treatment while mitoxantrone DEBs were less effective than. Irinotecan showed little effect for both DEBs and free drug. Apoptosis was not different between free mitoxantrone and the DEB form while more apoptosis induction was observed in cells incubated with free doxorubicin and irinotecan. Experimental PC was produced in mice. The therapeutic efficiency of either mitoxantrone and doxorubicin DEB or free drugs were compared. Mice were treated either once on day 12 or by 3 repetitive applications on days 7, 10 and 12. Mice treated by DEBs showed less weight loss and mortality. Therapeutic effect was determined by measuring tumor volume and tumor load on the day 15 after tumor inoculation. For the single application on the day 12, an advantage could be observed for the free drugs. After 3 repeated injections of both free and mitoxantrone DEB no difference in tumor load or tumor volume could be observed. Least tumor load and tumor volume was observed in mice that received 3 repeated injections of doxorubicin DEB. No animal survived 3 injections of free doxorubicin. We conclude that bead encapsulation of chemotherapeutic drugs may show the advantage of less toxicity in peritoneal spread of colorectal cancer. © 2008 Wiley‐Liss, Inc.