bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic Assemblies and Photophysical Changes of Zinc Porphyrin Dimer Regulated by N‐Containing Ligands
Authors: ZHOU Zai‐Chun , HE Lin , ZHU Yi‐Zhou , ZHENG Jian‐Yu
Published: November 2007

Zinc porphyrin dimer (1) has been designed and synthesized as a novel host of N‐containing ligands. The assembly behavior and photophysical changes of its host‐guest complexes were evaluated by 1H NMR, fluorescence, and UV‐visible titrations, and the processes reveal that the host‐guest assembly first creates a stable sandwich complex, then an axial coordination equilibrium appears between the sandwich complex and free ligand. The changes of absorption spectra of the assembly processes rely on the stabilities of the complexes, and fluorescence quenching depends on the axial coordination equilibrium, which indicates that the axial ligation/de‐ligation dynamics is indeed a pathway from the excited state to the ground state for metalloporphyrin complexes.
Preconcentration and Determination of Copper(II) Using Octadecyl Silica Membrane Disks Modified by 1,5‐Diphenylcarhazide and Flame Atomic Absorption Spectrometry
Authors: MOGHIMI Ali
Published: November 2007

A simple and reproducible method for the rapid extraction and determination of trace amounts of copper(II) ions using octadecyl‐bonded silica membrane disks modified by 1,5‐diphenylcarbazide (DPC) and atomic absorption spectrometry was presented, which was based on complex formation on the surface of the ENVI‐18 DISKTM disks followed by stripping of the retained species by minimum amounts of appropriate organic solvents. The elution was efficient and quantitative. The effect of potential interfering ions, pH, ligand amount, stripping solvent, and sample flow rate were also investigated. Under the optimal experimental conditions, the break‐through volume was found to be about 1000 mL providing a preconcentration factor of 400. The maximum capacity of the disks was found to be (255±5) µg for Cu2+, and the limit of detection of the proposed method was 5 ng per 1000 mL. The method was applied to the extraction and recovery of copper in different water samples.
L‐Proline Catalyzed Solvent‐Free Knoevenagel Condensation for the Synthesis of 3‐Substituted Coumarins
Authors: KARADE Nandkishor. N. , GAMPAWAR Sumit V. , SHINDE Sandeep. V. , JADHAV Wamanrao. N.
Published: November 2007

L‐Proline was utilized as an efficient organo‐catalyst for the environmentally benign synthesis of 3‐substituted coumarins by the Knoevenagel condensation of substituted 2‐hydroxybenzaldehydes with reactive methylene compounds under solvent free conditions.
New Sesquiterpene Glycosides from Culture Hairy Roots of Catharanthus roseus
Authors: CHUNG ILL‐Min , ALI Mohd , CHUN Se‐Chul , LEE Sun‐Joo , SAN Ka‐Yiu , CHRISTIE A. M. Peebles , AHMAD Ateeque
Published: November 2007

Two new compounds cadin‐2‐en‐1β‐ol‐1β‐D‐glucuronopyranoside (1), guaia‐1,7‐dien‐3β,13‐diol‐13α‐D‐ glucofuranoside (2) along with three known compounds have been isolated from the culture hairy roots of Catharanthus roseus. Their structures have been elucidated with the help of 500 MHz NMR using 1D and 2D spectral methods: viz: 1H and 13C NMR, 1H‐1H COSY, 1H‐13C HETCOR and DEPT aided by EIMS, FAB‐MS, HR‐FABMS and IR spectroscopy.
Kinetic Resolution of 2‐Chloro‐1‐(3,4‐dichlorophenyl)ethanol by Lipase‐Catalyzed Transesterification
Authors: WANG Ming‐Hui , LI Ya‐Feng , LIU Yong‐Jun , ZHANG Shu‐Sheng
Published: November 2007

Kinetic resolution of racemic 2‐chloro‐1‐(3,4‐dichlorophenyl)ethanol was performed by free Alcaligene sp. lipase‐catalyzed irreversible transesterification affording the (R)‐isomer with ≧ 95% ee and the (S)‐isomer with ≧ 90% ee. The activity of lipase Alcaligene sp. strongly depends on the basicity of the reaction system, and an organic base such as triethylamine can enhance the activity of the lipase and enantioselectivity markedly.
A Convenient Synthesis of 2‐Arylnaphtho[1,2‐d]oxazole Derivatives Promoted by Triethylamine
Authors: LI Hong , WEI Kun , WU Yang‐Jie
Published: November 2007

A variety of 2‐arylnaphtho[1,2‐d]oxazole derivatives were efficiently synthesized in moderate to high yields by the reaction of aromatic aldehydes with 1‐amino‐2‐naphthol derivatives in the presence of triethylamine in refluxing ethanol in air. Seven new 2‐arylnaphtho[1,2‐d]oxazole derivatives were obtained and characterized by the spectral data and elemental analysis. In addition, the X‐ray crystal structures of 2‐[4‐(N,N‐dimethylamino)phenyl]naphtho[1,2‐d] oxzole (3d) and 1,1′‐bis(naphtho[1,2‐d]oxazol‐2‐yl)ferrocene (3n) have been determined.
Supramolecular Assemblies in Salts of 2,2′‐Biimidazole with 5‐Sulfosalicylic Acid and 3,4,5‐Trihydroxybenzoic Acid
Authors: LI Yan‐Ping , YANG Pin
Published: November 2007

Supramolecular assemblies of 2,2′‐biimidazole with 5‐sulfosalicylic acid and 3,4,5‐trihydroxybenzoic acid, have been synthesized and characterized by single‐crystal X‐ray diffraction methods. Both the two proton‐transfer compounds of 2,2′‐biimidazole with 3‐carboxy‐4‐hydroxybenzenesulfonic acid (5‐sulfosalicylic acid, 5‐SSA) [namely bis(2‐(2‐1H‐imidazolyl)‐1H‐imidazolium) 4‐hydroxybenzene‐3‐carboxylate‐1‐sulfonate monohydrate, 2(C6H7N4)+· C7H4O6S2−·H2O, (I)] and 3,4,5‐trihydroxybenzoic acid [namely 2,2′‐bi‐1H‐imidazolium bis(3,4,5‐trihydroxybenzoate) tetrahydrate, C6H8N42+·2(C7H5O5)−·4(H2O), (II)] feature extensively hydrogen‐bonded three‐dimensional network structures having significant interlayer π‐ π interactions between the cation and anion species. In I, a 5‐SSA2− dianionic species results from deprotonation of both the sulfonic and the carboxylic acid groups, all available O‐atom acceptors interact with all cation and water molecule donors by hydrogen bonds. In II, the formula unit displays a crystallographic inversion symmetry. The structural information about the two complexes between 2,2′‐biimidazole compound and benzenecarboxylic acids obtained in this work will be particularly important for the rational design of supramolecular organic functional materials.
Expression and Purification of ZNF191(243–368) in Three Expression Systems
Authors: ZHAO Dong‐Xin , TENG Xin‐Cheng , DING Zhi‐Chun , HUANG Zhong‐Xian
Published: November 2007

ZNF191(243–368), a new human zinc finger protein, probably relates to some hereditary diseases and cancers. To obtain adequate amount of ZNF191(243–368) for the study of its property, structure and function, three different expression systems of inclusion‐body, glutathione S‐transferase (GST), and hexahistidine (6×His) were used and compared. Among these systems, the expression level of ZNF191(243–368) was increased in inclusion body system under a higher isopropylthio‐β‐D‐galactoside (IPTG) concentration, but the non‐target proteins were also increased more, which made its purification more difficult and the yield lower. The expression of His‐tag fusion protein was almost not affected by IPTG concentration, temperature and inducing time. At a high IPTG concentration the highest expression yield for GST fusion protein was obtained. And the fusion proteins can be partially purified by a single affinity chromatography step. The fusion protein systems show advantages for expression of these proteins.
Synthesis, X‐ray Structure and Aggregation Effect of Tetramethoxy Substituted Dibenzo[fg,op]naphthacene
Authors: CHENG Xiao‐Hong , FU Chang‐Jin
Published: November 2007

Tetramethoxy substituted dibenzo[fg,op]naphthacene was synthesised by using Friedel‐Crafts acylation, tandem Aldol‐Michael solvent‐free reaction and palladium catalyzed dehydrohalogenation cyclization as key steps. The X‐ray structure of the product and its aggregation effect in solvent were also reported.
Novel interaction partners of Bardet‐Biedl syndrome proteins
Authors: Oeffner F. , Moch C. , Neundorf A. , Hofmann J. , Koch M. , Grzeschik K. H.
Published: November 2007

Bardet‐Biedl syndrome (BBS) is a rare, developmental disorder characterized by six major symptoms: rod‐cone dystrophy, obesity, polydactyly, renal abnormalities, learning difficulties, and hypogonadism. Secondary features include cardiac and hepatic anomalies, metabolic disturbancies, and hearing loss. BBS is genetically heterogeneous with 12 disease genes (BBS1–BBS12) described thus far. Current data suggest a functional disturbance in ciliary function and intraflagellar transport being associated with the phenotype. However, the precise functions of the BBS proteins have yet to be elucidated. This study focuses on the detection of protein factors interacting with BBS proteins. Applying yeast two‐hybrid (Y2H) technology we found a series of novel, functionally potentially plausible binding partners of BBS1, BBS2, BBS4, and BBS7. Protein interactions were supported by coimmunoprecipitation analyses (ALDOB, EPAS1) and substantiated by colocalization studies at the subcellular level (ALDOB, EXOC7, FLOT1, KRT18, PAX2). Our work provides new insights into the understanding of BBS interactions and thus their biological function. Cell Motil. Cytoskeleton 2007. © 2007 Wiley‐Liss, Inc.
MRI evaluation of pathologically complete response and residual tumors in breast cancer after neoadjuvant chemotherapy
Authors: Chen Jeon Hor , Feig Byon , Agrawal Garima , Yu Hon , Carpenter Philip M. , Mehta Rita S. , Nalcioglu Orhan , Su Min Ying
Published: November 2007

BACKGROUND.

This study investigated the role of magnetic resonance imaging (MRI) in evaluation of pathologically complete response and residual tumors in patients who were receiving neoadjuvant chemotherapy (NAC) for both positive and negative HER‐2 breast cancer.

METHODS.

Fifty‐one individuals, comprised of 25 HER‐2 positive and 26 HER‐2 negative patients, were included in the study. Serial MRI studies were acquired before, during, and after NAC. On the basis of the final MRI, response was determined to be a clinically complete response ([CCR], no enhancement), probable CCR (residual enhancement equal to or less than that of glandular tissue), or residual tumor. All patients received surgery. Pathological outcomes were categorized as 1) no residual cancer, 2) no residual invasive cancer but ductal carcinoma in situ (DCIS) present, or 3) residual invasive cancer. The pathologically complete response (pCR) was defined as no invasive cancer.

RESULTS.

Complete clinical response as seen through MRI, including CCR and probable CCR, was identified in 35 (35 of 51, 69%) patients. MRI correctly diagnosed pCR in 26 (26 of 35, 74%) patients, including 18 of 19 (95%) patients in the HER‐2 positive group and 8 of 16 (50%) patients in the HER‐2 negative group (P < .005). The accuracy of MRI in identifying pCR varied according to the chemotherapy agent that was administered. MRI was more accurate in identifying pCR in patients who were receiving trastuzumab and less accurate in patients receiving bevacizumab. The high false‐negative rate found in HER‐2 negative patients was associated with residual disease that presented as scattered cells or small foci. In cases with residual bulk tumor, the lesion size, determined by MRI, correlated highly with that found in histopathological measurements (r = 0.93).

CONCLUSIONS.

MRI may predict pCR with high accuracy in HER‐2 positive patients, but it has a high false‐negative rate in HER‐2 negative patients, particularly in patients who are receiving antiangiogenic agents. Results indicate that the chemotherapy agent should be taken into consideration when using MRI to interpret therapeutic outcomes. More studies are needed to establish the role of MRI in managing, especially surgical planning, patients who are receiving NAC. Cancer 2008. © 2007 American Cancer Society.
Cancer in Appalachia, 2001–2003
Authors: Wingo Phyllis A. , Tucker Thomas C. , Jamison Patricia M. , Martin Howard , McLaughlin Colleen , Bayakly Rana , Bolick‐Aldrich Susan , Colsher Pat , Indian Robert , Knight Karen , Neloms Stacey , Wilson Reda , Richards Thomas B.
Published: November 2007

BACKGROUND.

Researchers have not been able to examine cancer incidence rates in Appalachia because high‐quality data have not been uniformly available across the region. This study is the first to report cancer incidence rates for a large proportion of the Appalachian population and describe the differences in incidence rates between Northern, Central, and Southern Appalachia.

METHODS.

Forty‐four states and the District of Columbia provided information for the diagnosis years 2001 through 2003 from cancer registries that met high‐quality data criteria. Eleven of 13 states with counties in Appalachia, covering 88% of the Appalachian population, met these criteria; Virginia and Mississippi were included for 2003 only. SEER*Stat was used to calculate age‐adjusted rates per 100,000 population and 95% gamma confidence limits.

RESULTS.

Overall, cancer incidence rates were higher in Appalachia than in the rest of the US; the rates for lung, colon/rectum, and other tobacco‐related cancers were particularly high. Central Appalachia had the highest rates of lung (men: 143.8; women: 75.2) and cervical cancer (11.2)—higher than the other 2 regions and the rest of the US. Northern Appalachia had the highest rates for prostate, female breast, and selected other sites, and Southern Appalachia had the lowest overall cancer incidence rates.

CONCLUSIONS.

Cancer incidence rates in Appalachia are higher than in the rest of the US, and they vary substantially between regions. Additional studies are needed to understand how these variations within Appalachia are associated with lifestyle, socioeconomic factors, urban/rural residence, and access to care. Cancer 2008. Published 2007 by the American Cancer Society.
On the applicability of the pseudospectral Legendre method for edge detection
Authors: Ahmad Falih H. , Castellane Ray M. , Miller Ernest L.
Published: November 2007

The pseudospectral Legendre method is utilized to develop a gradient detector. This detector is proposed in this communication for the detection of edges in discrete images. The detector can be applied in both the horizontal and vertical directions. It is a separable detector where the smoothing orthogonal part resembles a one‐dimensional notch filter. Discrete Canny's criteria values of the detector are similar to those of other known basic derivative filters. An example is given in which this detector is utilized and its applicability and validity are supported using comparison results from the use of the Sobel filter. Copyright © 2007 John Wiley & Sons, Ltd.
The Czochralski Method ‐ where we are 90 years after Jan Czochralski’s invention
Authors: Müller G.
Published: November 2007

The Czochralski method, i.e. pulling a crystal from the melt, became the most important technology for the production of large semiconductor (Si, GaAs, InP, GaP …) and optical crystals (oxides, CaF2…). The present status is achieved by a profound analysis of the mechanisms of heat and species transport which are relevant for the stability of the Czochralski growth process and the performance of the growing crystal. It was clearly demonstrated in the last few years that modeling by numerical simulation is an indispensable tool to analyze the Czochralski process and to understand the governing mechanisms. The contribution presents examples of this kind of modeling the Czochralski technique in correlation with experimental investigations in order to illustrate the present status of understanding relevant processing phenomena. Furthermore, it is shown what problems need still to be solved in the future in order to further improve the yield and quality of Czochralski‐grown crystals. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bulk growth of gallium nitride: challenges and difficulties
Authors: Bockowski M.
Published: November 2007

The present status of the GaN bulk growth by High Pressure Solution (HPS) method and combination of HPS and Hydride Vapor Phase Epitaxy (HVPE) methods is reviewed. Up to now the spontaneous high pressure solution growth of GaN results in crystals having habit of hexagonal platelets of surface area of 3 cm2 or needles with length up to 1 cm. Recently, the platelets and needles have been used as seeds for the HVPE growth. On the other hand, the LPE technique under pressure with pressure‐grown GaN (hp‐GaN), GaN/sapphire template, patterned GaN/sapphire template and free standing HVPE GaN as seeds has been examined and developed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth morphology of crystals from kinetic and geometric perspective
Authors: Prywer J. , Krasiński M. J.
Published: November 2007

The growth morphology of crystals is analysed from macroscopic point of view and the recent developments in this field are surveyed. In particular, it is shown that, for specific geometry characterized by interfacial angles a given face can increase in size for a very wide range of relative growth rates and need not be the slow‐growing face. Even growing faster than the neighbouring faces, such a face can increase in its size. However, there are other faces with other specific geometry, which can decrease the size growing more slowly than one of the neighbouring faces. If the growth time is sufficiently long, such a face may disappear and not be represented in the final crystal morphology. In the present survey the concepts given earlier [5] are extended. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Measurement of specific surface free energy of ruby and quartz single crystals using contact angle of liquids
Authors: Suzuki Takaomi , Sugihara Naoki , Iguchi Eiichi , Teshima Katsuya , Oishi Shuji , Kawasaki Masayuki
Published: November 2007

The specific surface free energy of ruby and quartz single crystal was experimentally obtained using contact angle of water and formamide droplets on the crystal surfaces, and compared with the morphology of each crystal. The ruby crystals satisfied Wulff's relationship even though their shape were not equilibrium form. The specific surface free energies of the growing faces of synthetic quartz crystal, ‐X, +X, Z, and S faces were obtained as 51.9, 55.6, 57.4, and 58.9 mN/m, respectively. The growth rates of these faces were 0.09, 0.23, 0.28, and 0.33 mm/day, respectively. The growth rate of each face of the quartz crystal can be regarded as a function of the experimentally obtained specific surface free energy. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of in‐plane structures of vapor deposited thin‐films of distyryl‐oligothiophenes by grazing incidence x‐ray diffractometry
Authors: Yoshimoto Noriyuki , Aosawa Keijyu , Taniswa Toshinori , Omote Kazuhiko , Ackermann J. , Videlot‐Ackermann C. , Brisset H. , Fages F.
Published: November 2007

The in‐plane structures of vapor deposited ultrathin films of distyryl‐oligothiophenes (DS‐2T) on SiO2 substrate were characterized by grazing incidence x‐ray diffractometry (GIXD). Two polymorphs, low‐temperature and high‐temperature phases, were identified, and the two dimensional unit cell parameters were determined for each polymorph. The polymorphism depends on substrate temperature and film thickness. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
In situ study of growth and dissolution kinetics of ammonium oxalate monohydrate single crystals from aqueous solutions containing cationic impurities
Authors: Sangwal K. , Wójcik K. , Borc J.
Published: November 2007

The results of an in situ investigation of the effect of four different bi‐ and trivalent cations (Fe(III), Cu(II), Mn(II) and Cr(III)) on the displacement velocity of individual growth steps on the (110) face of ammonium oxalate monohydrate crystals as a function of supersaturation are described and discussed. It was observed that: (1) at a particular temperature of pure solutions and solutions containing impurities, the velocity v of movement of the [110] growth steps is always greater than that of the [111] steps, (2) fluctuations in the velocity of individual growth steps occur in all solutions containing similar concentrations of different impurities, (3) the value of kinetic coefficient β for growth steps decreases with an increase in the concentration ci of Cu(II) impurity, but that for dissolution steps does not depend on ci; moreover, the value of kinetic coefficient β for growth steps is higher than that of dissolution steps, and (4) in the presence of Mn(II) and Cr(III) impurities, the kinetic coefficient β for dissolution steps is several times greater than that for growth steps. The results are explained from the standpoint of Kubota‐Mullin model of adsorption of impurities at kinks in the steps and the stability of dominating complexes present in solutions. Analysis of the results revealed that: (1) the effectiveness of different impurities in inhibiting growth increases in the order: Fe(III), Cu(II), Mn(II), and Cr(III), and this behavior is directly connected with the stability and chemical constitution of dominating complexes in saturated solutions, (2) fluctuations in the velocity of growth steps is associated with the effectiveness of an impurity for adsorption; the stronger the adsorption of an impurity, the higher is the fluctuation in step velocity v, and (3) depending on the nature of the impurity, the kinetic coefficient for the dissolution steps can remain unchanged or can be higher than that of the growth steps. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
3D simulation of the effects of growth parameters on the growth of sapphire crystals using heat exchanger method
Authors: Lu Chung‐Wei , Chi Pei‐Hung
Published: November 2007

3D simulations using the commercial CFDRC and FIDAP code, which are based on finite element techniques, were performed to investigate the effects of anisotropic conductivity on the convexity of the melt–crystal interface and the hot spots of sapphire crystal in a heat‐exchanger‐method crystal growth system. The convection boundary conditions of both the energy input to the crucible by the radiation as well as convection inside the furnace and the energy output through the heat exchanger are modeled. The cross‐sectional flow pattern and the shape of the melt–crystal interface are confirmed by comparing the 3‐D modeling results with previous 2D simulation results. In the 3D model, the “hot spots” in the corners of the crucible are donut shaped, and the shape changes with the value of the conductivity of anisotropic crystal. The outline of the crystal becomes more convex as the conductivity in the z direction (ksz) increases. The outline of melt–crystal interface is elliptical when the anisotropic conductivity is moving in the radial direction (ksx and ksy). The portion at the outline touching the bottom of the crucible is smaller than the maximum outline of the crystal, meaning that the shape at the “hot spot”, changes with the value of the conductivities of anisotropic crystal. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigation of GaN crystal quality on silicon substrates using GaN/AlN superlattice structures
Authors: Wu Gwo‐Mei , Tsai Chen‐Wen , Chen Nie‐Chuan , Chang Pen‐Hsiu
Published: November 2007

The crystal quality of GaN thin film on silicon using GaN/AlN superlattice structures was investigated. The growth was carried out on Si(111) for GaN(0001) in a metal‐organic vapor phase epitaxy system. Various GaN/AlN superlattice intermediate layers have been designed to decrease the dislocation density. The results showed that the etch pit density could be greatly reduced by one order of magnitude. Cross‐sectional transmission electron microscopy (XTEM) study confirmed the efficiency of GaN/AlN superlattice in blocking threading dislocation propagation in GaN crystal. The design of nine period GaN/AlN (20nm/2nm) superlattice has been evidenced to be effective in reducing the dislocation density and improving the crystal quality. In addition, the dislocation bending in GaN/AlN interface and dislocation merging is investigated. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystal growth, optical and luminescence properties of (Ce,Sr)‐doped PrAlO3 single crystals
Authors: Novoselov A. , Yoshikawa A. , Solovieva N. , Nikl M.
Published: November 2007

Using the micro‐pulling‐down method, (Ce,Sr)‐doped PrAlO3 square‐shaped single crystals (4×4×12 mm) were grown. Structural parameters studied by X‐ray powder diffraction were consistent with R3m space group. Compositional homogeneity was checked with electron probe micro‐analysis and found quite uniform. Absorption spectra and luminescence characteristics under UV and X‐ray excitations were measured at room temperature with no Ce‐related emission appeared. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spectroscopic properties of a Tm3+:Bi2TeO5 single crystal
Authors: Dominiak‐Dzik G. , Ryba‐Romanowski W. , Lisiecki R. , Főldvári I.
Published: November 2007

Single crystal of bismuth tellurite Bi2TeO5 (BTO) doped with trivalent thulium (Tm3+) was grown by the Czochralski method and investigated by spectroscopic techniques (absorption, emission). Absorption and emission of the Tm:BTO crystal collected in the VIS‐IR spectral range are presented. Spectroscopic features were investigated as a function of the excitation light polarisation (E//X, Y, and Z axis of optical indicatrix) and sample temperature. The oscillator strength of the 3H6 → 3F4 transition at 1.7 μm was determined by numerical integration of the X, Y and Z polarised absorption spectra. The obtained values are: PX = 4.7 × 10−6, PY = 6.8 × 10−6 and PZ = 5.9 × 10−6 that gives a mean value Pmean = 5.8 × 10−6. Emission was observed from the 1G4 and 3H4 levels. The 3H4 and 1G4 excited state dynamics was studied. Decay curves and time constants of luminescence were collected at 5 and 300 K and analysed. The 3F4 → 3H6 luminescence at around 1.8 μm was too weak to be acquired from the low concentrated sample. However, based on optical data it was possible to estimate the radiative probability Arad of this transition and the 3F4 radiative lifetime. The resultant values are: Arad = 668 ± 0.4 s−1 and τrad = 1.5 ms. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
XPS characterization of YAlO3:Co single crystals
Authors: Talik E. , Kruczek M. , Zarek W. , Kusz J. , Wójcik K. , Sakowska H. , Szyrski W.
Published: November 2007

YAlO3:Co (YAP:Co) single crystals have been obtained by the Czochralski method. The XPS spectra of YAP:Co annealed in reducing atmospheres: H2, vacuum and vacuum plus H2 are presented and discussed. As confirmed by magnetic measurements and the electron spectroscopy XPS the dopant concentration of Co is lower than a nominal one. The annealing processes removed colour centers due to relocation and some reduction of oxygen ions in the structure. The increased unit volume during the long annealing process may be caused by the change in some Co3+ ions into Co2+ ions. This explains the occurrence of the violet colour of the longtime annealed samples. The chemical shift analysis shows more ionic bond of Y–O than Al–O. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Physical properties of single crystalline CeNi4.2Mn0.8
Authors: Klimczak M. , Talik E. , Kusz J. , Kowalczyk A. , Toliński T.
Published: November 2007

A single crystal CeNi4.2Mn0.8 was grown by the Czochralski method from a levitating melt. The structural, magnetic, electrical transport and electronic structure properties were examined. X‐ray diffraction confirms the hexagonal structure. The f occupancy nf and the coupling Δ between the f level and the conduction states are derived to be about 0.95 and 100 meV, respectively. The X‐ray photoemission spectroscopy shows that Ce ions in CeNi4.2Mn0.8 are in the intermediate valance state. The temperature dependence of resistivity exhibits the metallic character of this compound and reveals a small inflection at 136 K. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On setting the DC voltage level of an active power filter
Authors: Lo Yu‐Kang , Pan Tian‐Fu , Wang Jian‐Min
Published: November 2007

A new strategy for setting the DC voltage level of an active power filter is proposed in this letter. By determining the peak slope of the command for the compensating current within a defined load range, an optimal value for the DC voltage level can be determined based on the trade‐off between an undistorted input current and a minimum switching loss. Experimental results conform well with the theoretical analysis. Copyright © 2007 John Wiley & Sons, Ltd.
The SMN binding protein gemin2 is not involved in motor axon outgrowth
Authors: McWhorter Michelle L. , Boon Kum‐loong , Horan Erin S. , Burghes Arthur H.M. , Beattie Christine E.
Published: November 2007

A paramount question in spinal muscular atrophy (SMA) research is why reduced levels of SMN, a ubiquitously expressed protein, leads to a motoneuron‐specific disease. It has been hypothesized that SMN may have a dual function: a role in snRNP assembly and a novel function that affects axons. We have previously shown that decreasing Smn levels in zebrafish causes defects in motor axon outgrowth. To determine whether decreasing other components of the snRNP complex would also cause motor axon defects, we knocked down Gemin2, a SMN binding protein involved in snRNP assembly. Moderate knockdown of Gemin2 yields a large percentage of morphologically abnormal embryos with shortened trunks and overall delayed development. Examination of motor axons revealed that only embryos with abnormal body morphology had aberrant motor axons indicating that the motor axon defects are secondary to the overall body defects observed in these embryos. To directly test this, we knocked down Gemin2 specifically in motoneurons using two separate approaches and found that motor axons developed normally. Furthermore, wild‐type neurons transplanted into morphologically abnormal gemin2 morphants had aberrant motor axons indicating that the motor axon defects observed when Gemin2 is decreased are secondary to the defects in body morphology. These data show that reduction of Gemin2, unlike reduction of SMN, in zebrafish embryos does not directly cause motor axon outgrowth defects. Since Gemin2 and SMN both function in snRNP biogenesis yet only SMN knockdown causes motor axon defects, these data are consistent with an additional role for SMN that is snRNP independent. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2008
Effect of astrocyte‐targeted production of IL‐6 on traumatic brain injury and its impact on the cortical transcriptome
Authors: Quintana Albert , Molinero Amalia , Borup Rehannah , Nielsen Finn Cilius , Campbell Iain L. , Penkowa Milena , Hidalgo Juan
Published: November 2007

Interleukin‐6 (IL‐6) is one of the key players in the response of the brain cortex to injury. We have described previously that astrocyte‐driven production of IL‐6 (GFAP‐IL6) in transgenic mice, although causing spontaneous neuroinflammation and long term damage, is beneficial after an acute (freeze) injury in the cortex, increasing healing and decreasing oxidative stress and apoptosis. To determine the transcriptional basis for these responses here we analyzed the global gene expression profile of the cortex, at 0 (unlesioned), 1 or 4 days post lesion (dpl), in both GFAP‐IL6 mice and their control littermates. GFAP‐IL6 mice showed an increase in genes associated with the inflammatory response both at 1 dpl (Iftm1, Endod1) and 4 dpl (Gfap, C4b), decreased expression of proapoptotic genes (i.e. Gadd45b, Clic4, p21) as well as reduced expression of genes involved in the control of oxidative stress (Atf4). Furthermore, the presence of IL‐6 altered the expression of genes involved in hemostasis (Vwf), cell migration and proliferation (Cap2), and synaptic activity (Vamp2). All these changes in gene expression could underlie the phenotype of the GFAP‐IL6 mice after injury, but many other possible factors were also identified in this study, highlighting the utility of this approach for deciphering new pathways orchestrated by IL‐6. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2008
Gastrulation in the spider Zygiella x‐notata involves three distinct phases of cell internalization
Authors: Chaw R. Crystal , Vance Emily , Black Steven D.
Published: November 2007

The cell movements of gastrulation were analyzed in embryos of the spider Zygiella x‐notata, using time‐lapse video, cell tracing, and improved histology. Cells are internalized near the center of the germ disc in three distinct phases. First, cumulus mesenchyme cells ingress and migrate as a group beneath the superficial layer. Second, mass internalization through a blastopore yields a diffusely organized deep layer. Third, superficial cells accumulate at the center of the germ disc to form the caudal bud. The floor is internalized, and the caudal bud moves over the nascent dorsal field to form the caudal lobe. This pattern of gastrulation differs from the canonical pattern described in the historical literature: (1) the cumulus of Z. x‐notata is completely formed before any other cells internalize; and (2) the caudal lobe is formed by means of the caudal bud, which is a locus of cell internalization. Developmental Dynamics 236:3484–3495, 2007. © 2007 Wiley‐Liss, Inc.
The commonly used marker ELAV is transiently expressed in neuroblasts and glial cells in the Drosophila embryonic CNS
Authors: Berger Christian , Renner Simone , Lüer Karin , Technau Gerhard M.
Published: November 2007

Glial cells in the Drosophila embryonic nervous system can be monitored with the marker Reversed‐polarity (Repo), whereas neurons lack Repo and express the RNA‐binding protein ELAV (Embryonic Lethal, Abnormal Vision). Since the first description of the ELAV protein distribution in 1991 (Robinow and White), it is believed that ELAV is an exclusive neuronal and postmitotic marker. Looking at ELAV expression, we unexpectedly observed that, in addition to neurons, ELAV is transiently expressed in embryonic glial cells. Furthermore, it is transiently present in the proliferating longitudinal glioblast, and it is transcribed in embryonic neuroblasts. Likewise, elav‐Gal4 lines, which are generally used as postmitotic neuronal driver lines, show expression in neural progenitor cells and nearly all embryonic glial cells. Thus, in the embryo, elav can no longer be considered an exclusive marker or driver for postmitotic neurons. elav loss‐of‐function mutants show no obvious effects on the number and pattern of embryonic glia. Developmental Dynamics 236:3562–3568, 2007. © 2007 Wiley‐Liss, Inc.
DjCBC‐1, a conserved DEAD box RNA helicase of the RCK/p54/Me31B family, is a component of RNA‐protein complexes in planarian stem cells and neurons
Authors: Yoshida‐Kashikawa Maki , Shibata Norito , Takechi Katsuaki , Agata Kiyokazu
Published: November 2007

The stem cells of planarians, known as neoblasts, can give rise to all cell types in planarians. Neoblasts can be identified by electron microscopy as cells with electron‐dense chromatoid bodies, which are large RNP (ribonucleoprotein) complexes, in their cytoplasm. However, the components and function of chromatoid bodies are still relatively unknown. Here we identified a DEAD box RNA helicase gene of the RCK/p54/Me31B family from a planarian EST database and showed the localization of its product in chromatoid bodies by immunoelectron microscopy. We named this gene Djcbc‐1 (Dugesia japonica chromatoid body component 1). Djcbc‐1 was also strongly expressed in the brain and in the germline stem cells of sexualized planarians. We observed chromatoid body‐like electron‐dense bodies in brain neurons, where DjCBC‐1 was also expressed. These observations suggest that common molecular components of RNP complexes may be involved in the regulation of somatic and germline stem cells, and neurons in planarians. Departmental Dynamics 236:3436–3450, 2007. © 2007 Wiley‐Liss, Inc.
A Combined Experimental and Theoretical Study of Anion–π Interactions in Bis(pyr­imidine) Salts
Authors: Garcia‐Raso Angel , Albertí Francisca M. , Fiol Juan J. , Tasada Andrés , Barceló‐Oliver Miquel , Molins Elies , Escudero Daniel , Frontera Antonio , Quiñonero David , Deyà Pere M.
Published: November 2007

We report the synthesis and X‐ray characterization of an N,N′‐tetramethylenebis(2‐aminopyrimidinium) tetrafluoroborate salt that exhibits anion–π interactions that are responsible for the crystal packing. The anion forms a sandwich complex with two pyrimidine rings. When the anion is nitrate, the crystal packing is governed by anion–π interactions and hydrogen bonds, and the sandwich complex is not formed. Finally, a theoretical study of the anion–π interactions in charged pyrimidine rings is in good agreement with the experimental findings. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Dynamics of multiple intertidal bars over semi‐diurnal and lunar tidal cycles, North Lincolnshire, England
Authors: Houwelingen Selma van , Masselink Gerhard , Bullard Joanna
Published: November 2007

Multiple intertidal bars are common features of wave‐dominated sandy beaches, yet their short‐term (<1 month) and small‐scale (<1 km) morphology and dynamics remain poorly understood. This study describes the morphodynamics of multiple intertidal bars in North Lincolnshire, England, during single and lunar tidal cycles under two contrasting conditions – first when significant wave height was <0·5 m and second when significant wave height frequently exceeded 1 m. The relative importance of swash, surf and shoaling processes in determining morphological change was examined using detailed field observations and a numerical model. The beach featured four intertidal bars and both cross‐shore and longshore bar morphology evolved during the field investigation, particularly under medium to high wave‐energy conditions. Numerical modelling suggests shoaling processes are most common on the seaward two bars under calm wave conditions (Hs < 0·5 m) and that surf zone processes become more common during neap tides and under more energetic (Hs < 0·5 m) conditions. Surf processes dominate the inner two bars, though swash influence increases in a landward direction. The numerical modelling results combined with low tide survey data and high‐resolution morphological measurements strongly suggest changes in the intertidal bar morphology are accomplished by surf zone processes rather than by shoaling wave or swash processes. This is because shoaling waves do not induce significant sediment transport to have any morphological effect, whereas swash action generally does not have enough scope to act as the swash zone is much narrower than the surf zone. It was found, however, that the absolute rate of morphological change under swash action and surfzone processes are of similar magnitudes and that swash action may induce a significant amount of local morphological change when the high tide mark is located on the upper bar, making this process important for bar morphodynamics. Copyright © 2007 John Wiley & Sons, Ltd.
tPA‐mediated generation of plasmin is catalyzed by the proteoglycan NG2
Authors: Nolin Westley B. , Emmetsberger Jaime , Bukhari Noreen , Zhang Yan , Levine Joel M. , Tsirka Stella E.
Published: November 2007

Paralysis resulting from spinal cord injury is devastating and persistent. One major reason for the inability of the body to heal this type of injury ensues from the local increase of glial cells leading to the formation of a glial scar, and the upregulation of chondroitin sulfate proteoglycans (CSPGs) at the site of injury through which axons are unable to regenerate. Experimental approaches to overcome this problem have accordingly focused on reducing the inhibitory properties of CSPGs, for example by using chondroitinase to remove the sugar chains and reduce the CSPGs to their core protein constituents, although this step alone does not provide dramatic benefits as a monotherapy. Using in vitro and in vivo approaches, we describe here a potentially synergistic therapeutic opportunity based on tissue plasminogen activator (tPA), an extracellular protease that converts plasminogen (plg) into the active protease plasmin. We show that tPA and plg both bind to the CSPG protein NG2, which functions as a scaffold to accelerate the tPA‐driven conversion of plg to plasmin. The binding occurs via the tPA and plg kringle domains to domain 2 of the NG2 CSPG core protein, and is enhanced in some settings after chondroitinase‐mediated removal of the NG2 proteoglycan side chains. Once generated, plasmin then degrades NG2, both in an in vitro setting using recombinant protein, and in vivo models of spinal cord injury. Our finding that the tPA and plg binding is in some instances more efficient after exposure of the NG2 proteoglycan to chondroitinase treatment suggests that a combined therapeutic approach employing both chondroitinase and the tPA/plasmin proteolytic system could be of significant benefit in promoting axonal regeneration through glial scars after spinal cord injury. © 2007 Wiley‐Liss, Inc.
Long‐term potentiation inhibition by low‐level N‐methyl‐D‐aspartate receptor activation involves calcineurin, nitric oxide, and p38 mitogen‐activated protein kinase
Authors: Izumi Yukitoshi , Tokuda Kazuhiro , Zorumski Charles F.
Published: November 2007

Low‐level activation of N‐methyl‐d‐aspartate receptors (NMDARs) results in a decrease in the ability of tetanic stimulation to induce long‐term potentiation (LTP). This NMDAR‐mediated LTP inhibition is observed with low micromolar concentrations of NMDA or chelation of ambient extracellular zinc. In rat hippocampal slices, we examined whether LTP inhibition by 1 μM NMDA and zinc chelation share common mechanisms. We found that both forms of LTP inhibition involve nitric oxide (NO) synthase (NOS) and calcineurin. Furthermore, both forms of LTP inhibition are overcome by block of p38 mitogen‐activated protein kinase (MAPK), but not by inhibition of extracellular signal‐regulated kinase 1/2 or c‐Jun‐N‐terminal kinase. A p38 antagonist also overcame the block of LTP by sodium nitroprusside, an agent that releases NO, suggesting that NO release occurs upstream of MAPK activation. Despite the involvement of p38 MAPK in NMDAR‐mediated LTP inhibition, p38 antagonism did not enhance LTP induction in response to weak tetanic stimulation under baseline conditions. These results indicate that p38 MAPK is part of a complex NMDAR‐driven signaling pathway involving calcineurin and NO that helps to regulate synaptic plasticity in the CA1 region. © 2007 Wiley‐Liss, Inc.
Safety, immunogenicity, and efficacy of quadrivalent human papillomavirus (types 6, 11, 16, 18) L1 virus‐like‐particle vaccine in Latin American women
Authors: Perez Gonzalo , Lazcano‐Ponce Eduardo , Hernandez‐Avila Mauricio , García Patricia J. , Muñoz Nubia , Villa Luisa L. , Bryan Janine , Taddeo Frank J. , Lu Shuang , Esser Mark T. , Vuocolo Scott , Sattler Carlos , Barr Eliav
Published: November 2007

The prevalence of HPV infection in Latin America is among the highest in the world. A quadrivalent (types 6/11/16/18) human papillomavirus L1 virus‐like‐particle vaccine has been shown to be 95–100% effective in preventing HPV 6/11/16/18‐related cervical and genital disease in women naïve to vaccine HPV types. A total of 6,004 female subjects aged 9–24 were recruited from Brazil, Mexico, Colombia, Costa Rica, Guatemala and Peru. Subjects were randomized to immunization with intramuscular (deltoid) injections of HPV vaccine or placebo at enrollment (day 1), month 2 and month 6. Among vaccinated subjects in the per‐protocol population from Latin America, quadrivalent HPV vaccine was 92.8 and 100% effective in preventing cervical intraepithelial neoplasia and external genital lesions related to vaccine HPV types, respectively. These data support vaccination of adolescents and young adults in the region, which is expected to greatly reduce the burden of cervical and genital cancers, precancers and genital warts. © 2007 Wiley‐Liss, Inc.
On the design of a real‐time knowledge‐based system for managing logistics operations
Authors: Chow K. H. , Choy K. L. , Lee W. B.
Published: November 2007

Over the past 10 years, various kinds of logistics information systems have been developed to store and process all sorts of data and information to support daily logistics operations. However, the logistics planning or decision‐making of logistics activity is still executed manually. In this paper, a real‐time knowledge‐based system (RKBS) is designed to support logistic service providers in making decisions during the stage of logistics planning and operation by extracting, sharing and storing real‐time logistics knowledge. The proposed system, which is suitable for usage in different business processes in a warehouse operating environment, is developed by integrating radio‐frequency identification, online analytical processing, case‐based reasoning technologies, and a branch‐and‐bound resource‐route‐optimizing programming model. Through applying the RKBS in GENCO, a US‐based logistics service company, the overall logistics servicing level is enhanced through accurate decision‐making and planning of warehouse operations. Copyright © 2007 John Wiley & Sons, Ltd.
A genetic algorithm approach to detecting temporal patterns indicative of financial statement fraud
Authors: Hoogs Bethany , Kiehl Thomas , Lacomb Christina , Senturk Deniz
Published: November 2007

This study presents a genetic algorithm approach to detecting financial statement fraud. The study uses a sample comprising a target class of 51 companies accused by the Securities and Exchange Commission of improperly recognizing revenue and a peer class of 339 companies matched on industry and size (revenue). Variables include 76 comparative metrics, based on specific financial metrics and ratios that capture company performance in the context of historical and industry performance, and nine company characteristics. Time‐based patterns detected by the genetic algorithm accurately classify 63% of the target class companies and 95% of the peer class companies. Copyright © 2007 John Wiley & Sons, Ltd.
Index tracking with constrained portfolios
Authors: Maringer Dietmar , Oyewumi Olufemi
Published: November 2007

Passive portfolio management strategies, such as index tracking, are popular in the industry, but so far little research has been done on the cardinality of such a portfolio, i.e. on how many different assets ought to be included in it. One reason for this is the computational complexity of the associated optimization problems. Traditional optimization techniques cannot deal appropriately with the discontinuities and the many local optima emerging from the introduction of explicit cardinality constraints. More recent approaches, such as heuristic methods, on the other hand, can overcome these hurdles.

This paper demonstrates how one of these methods, differential evolution, can be used to solve the constrained index‐tracking problem. We analyse the financial implication of cardinality constraints for a tracking portfolio using an empirical study of the Down Jones Industrial Average. We find that the index can be tracked satisfactorily with a subset of its components and, more important, that the deviation between computed actual tracking error and the theoretically achievable tracking error out of sample is negligibly affected by the portfolio's cardinality. Copyright © 2007 John Wiley & Sons, Ltd.
Knowledge representation of rules: a note
Authors: O'Leary Daniel E.
Published: November 2007

This paper examines knowledge acquisition and representation of ‘if–then’ rules and the linkage between the two. It provides an empirical analysis of the relationship between using different knowledge representations that are logically equivalent. A priori, logically equivalent forms would be expected to result in gathering the same knowledge. However, this paper does not substantiate that conclusion. Instead, different logically equivalent representations used for knowledge elicitation can result in different orderings of the probability of events. As a result, elicitation and representation must be tightly linked. In addition, this paper finds that groups of non‐professionals can generate better orderings than individual professionals and non‐professionals. Copyright © 2007 John Wiley & Sons, Ltd.