bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential pulse anodic stripping voltammetric determination of lead with heparin modified electrode
Authors: Li Nian‐Bing , Duan Jian‐Ping , Chen Guo‐Nan
Published: September 2010

A novel differential pulse anodic stripping voltammetry for the determination of trace amounts of lead, using a biomacromolecule heparin drop‐coated modified glassy carbon electrode, has been described. Pb2‐ was deposited on the surface of a heparin‐modified electrode at ‐1.0 V (vs. SCE) via forming Pb2‐heparin and subsequent reduction at the electrode. In the following step, Pb‐heparin was oxidized, and voltammograms were recorded by scanning the potential in a positive direction. Conditions were optimized with respect to the pH of the medium, the mass of drop‐coated heparin, accumulation potential and accumulation time. The peak current was proportional to the Pb2‐ concentration in the range of 2.0X 10−‐9 to 7.0X 10−‐7 mol/L. The detection limit was 3.0X 10−‐10 mol/L. The relative standard deviation was 4.83% for 1.0X 10−‐8 mol/L Pb2‐ (n = 10). The developed method has been applied to the determination of Pb2‐ in water samples with satisfactory results.
A relative study on two‐photon absorption properties of C60 and C70
Authors: Zhou Xin , Ren Ai‐Min , Feng Ji‐Kang , Liu Xiao‐Juan
Published: September 2010

We have theoretically investigated the one‐ and two‐photon absorption properties of C60 and C70 using the ZINDO method. From the results it is suggested that the one‐photon absorption spectra are in agreement with the experimental observations. It is found that the maximum TPA cross section of C70 is more than twice that of C60 which is consistent with the experimental results. A notable point is that the TPA process of C60 is different from that of C70 as well as other ordinary conjugated molecules.
A novel silver(I) s̀‐complex supramolecular polymer: [Ag2(o‐HOPhCO2)2]n
Authors: Jian Fang‐Fang , Wang Qing‐Xiang , Zhao Pu‐Su , Jiao Kui
Published: September 2010

The hydrothermal reactions of sodium o‐hydroxybenzoate with AgNO3 yield a novel stable Ag(I) s̀‐complex supramolecular polymer, [Ag2(o‐HOPhCO2)2]n. The structure of [Ag2(o‐HOPhCO2)2] was solved by single crystal X‐ray diffraction analysis. It is monoclinic with space group P2Jc and unit cell parameters a=0.7394(2) nm, b= 0.8822(2) nm, c=1.0662(2) nm, β= 107.66(3)°, Z=4. The silver(I) atom is two‐coordinated by two carboxylic oxygen atoms of two o‐hydroxybenzoate ligands, and meanwhile, forms supramolecular interaction with one carbon atom of phenyl‐ring in the third o‐hydroxybenzoate group. The a‐form Ag…C supramolecular bond bridges [Ag2(o‐HOPhCO2)2] units into an infinite 2D layered polymer [Ag2(o‐HOPhCO2)2]n. The coordination sphere of the silver atom is best described as a distorted T‐shaped geometry.
Kinetic studies on the reaction of sodium hexa‐cyanoferrate(II) complex with peroxydisulfate anion
Authors: Meng Xiang‐Li , Yuan Cai‐Xia , Zhou Qing‐Hua , Li Miao‐Yu , Yang Pin
Published: September 2010

The oxidation of Na4Fe(CN)6 complex by S2O anion was found to follow an outer‐sphere electron transfer mechanism. We firstly carried out the reaction at pH=1. The specific rate constants of the reaction, kox, are (8.1±0.07)×10−2 and (4.3±0.1)×10−2 mol−1·L·s−1 at μ=1.0 mol·L−1 NaClO4, T=298 K for pH=1 (0.1 mol·L−1 HCl04) and 8, respectively. The activation parameters, obtained by measuring the rate constants of oxidation 283–303 K, were ΔH≠=(69.0±5.6) kJ·mol−1, ΔS≠=(−0.34±0.041)×102 J·mol−1·K−1 at pH=l and ΔH≠=(41.3±5.5) kJ·mol−1, ΔS≠=(−1.27±0.33)×102 J·mol−1·K−1 at pH=8, respectively. The cyclic voltammetry of Fe(CN) shows that the oxidation is a one‐electron reversible redox process with E1/2 values of 0.55 and 0.46 V vs. normal hydrogen electrode at μ=1.0 mol·L−1 LiClO4, for pH=1 and pH=8 (Tris). respectively. The kinetic results were discussed on the basis of Marcus theory.
Cochinchin from Dracaena cochinchinensis
Authors: He Lan , Wang Zhu‐Hong , Liu Xue‐Hui , Fang De‐Cai , Li Hua‐Min
Published: September 2010

A new compound, Cochinchin (1), together with 7,4′‐dihydroxyflavone (2), 7‐hydroxy‐4′‐methoxyflavane (3). 7‐hydroxy‐3‐(4‐hydroxybenzyl)chroman (4), 4′‐hydroxy‐2,4‐dimethoxydihydrochalcone (5) and 4′‐hydroxy‐2,4,6‐trimethoxydihydrochalcone (6) was isolated from the resin (trivial name, “dragon's blood”) of Dracaena cochinchinensis (Lour.) S. C. Chen. The structure of 1 was elucidated on the basis of spectroscopic data as (2,3‐trans)‐6‐allyl‐2‐(3,5‐dimethoxyphenyl)‐3‐(4‐hydroxyphenyl)‐2,3‐dihydrobenzo[1,4]dioxin which is a natural product possessing a new framework.
Elucidation of O‐phosphoryl and N‐phosphoryl amino acids by electrospray ionization tandem mass spectrometry
Authors: Zhang Jian‐Chen , Cao Shu‐Xia , Xu Jun , Liao Xin‐Cheng , Zhao Yu‐Fen
Published: September 2010

Mass spectroscopic characteristics of phosphoryl amino acids were studied in detail by positive and negative electrospray ionization mass spectrometry (ESI‐MS) in conjunction with tandem mass spectrometry (MS/MS). Besides N‐diisopropyloxyphosphoryl amino acids (N‐DIPP‐AA), O‐phospho‐ and O‐diisopropyloxyphosphoryl amino acids (O‐DIPP‐AA) were studied and compared to N‐DIPP‐AA. The fragmentation pathways of [M+H]+, [M+Na]+ and [M−H]− ions of phosphoryl amino acids were summarized. In addition to several similar patterns. each of them showed its characteristic fragmention.
Synthesis of 5,6‐Dihydro‐OSW‐1 and its antitumor activities
Authors: Deng Le‐Hua , Wu Hao , Yu Biao , Jiang Man‐Rong , Wu Jia‐Rui
Published: September 2010

5,6‐Dihydro‐OSW‐1 (1) was synthesized following our previous procedure for the total synthesis of OSW‐1. This compound demonstrated slightly stronger potency than that of OSW‐1 against the growth of cancer cells.
Reaction of ketene dithioacetals with pyrazolylcarbohydrazide: Synthesis and biological activities of ethyl 5‐amino‐1–(5′‐methyl‐1′‐t‐butyl‐4′‐pyrazolyl)carbonyl‐3‐methylthio‐1 H‐pyrazole‐4‐carboxylate
Authors: Li Ming , Wen Li‐Rong , Fu Wei‐Jun , Zhao Gui‐Long , Hu Fang‐Zhong , Yang Hua‐Zheng
Published: September 2010

The title compound, C16H23N5O3S, ethyl 5‐amino‐l‐(5′‐methyl‐l'‐t‐butyl‐4′‐pyrazolyl)carbonyl‐3‐methylthio 1H‐pyrazole‐4‐carboxylate (5) has been synthesized by the treatment of ethyl 2‐cyano‐3,3‐dimethylthioacrylate with 1 ‐t‐butyl‐5‐methyl‐4‐hydrazinocarbonylpyrazole (4) in refluxed ethanol. The possible mechanism of the above reaction was also discussed. The results of biological test show that the title compound has fungicidal and plant growth regulation activities.
Assembly synthesis of sheet‐like calcite array and stable‐vaterite by supported liquid membrane
Authors: Sun Dong‐Mei , Wu Qing‐Sheng
Published: September 2010

Sheet‐like calcite array and stable vaterite were synthesized by bio‐mimetic supported liquid membrane system under different reaction conditions. Both of the FTIR spectra of products showed narrower peak at 1418 cm−1 than that of bulk CaCO3, and that of vaterite has a split in this peak.
Thermokinetics on the reaction of formation of the ternary complex Nd[(C5H8NS2)3(C12H8N2)]
Authors: Fan Xue‐Zhong , Meng Xiang‐Xin , Chen San‐Ping , Jiao Bao‐Juan , Ren Yi‐Xia , Gao Sheng‐Li , Shi Qi‐Zhen
Published: September 2010

The title ternary complex Nd[(C5H8NS2)3(C12H8N2)] has been synthesized in absolute ethanol by the reaction of NdCl3·3.74H2O with ammonium pyrrolidmyldifhiocaboxylate (APDC) and 1,10‐phenanthroline (phen·H2O) at air atmosphere without any cautions against moisture. The bonding characteristics of the complex were characterized by IR, showing that Nd3+ is bonded with sulfur atom in the APDC and coordinated with nitrogen atom in the phen. TG‐DTG investigation indicates that the title complex was decomposed into Nd2S3 and deposited carbon in one step where Nd2S3 predominated in the final products. The enthalpy change of formation of the reaction on the title complex in liquid‐phase has been determined by a microcalorimeter. Thermodynamic parameters (the activation enthalpy, the activation entropy and the activation free energy) and kinetics parameters (the rate constant, the apparent activation energy, the pre‐exponential constant and the reaction order) of the title reaction have been calculated. The enthalpy change of the soLid‐phase reaction has been obtained by a thermochemistry cycle.
A novel photochemical reaction of 4‐bromo‐3‐methyl‐1‐phenyl‐4,5‐dihydro‐pyrazol‐5‐one
Authors: Xiao‐Liu L. I. , Song Zhi‐Yi , Meng Ji‐Ben
Published: September 2010

UV‐Irradiation of 4‐bromo‐3‐methyl‐l‐phenyl‐4,5‐dihydro‐pyrazol‐5‐one (1) in the presence of various aromatic hydrocarbons gave different types of photoproducts depending on the nature of the hydrocarbons via an electron‐transfer mechanism. In the presence of naphthalene or phenanthrene a photochemical homocoupling reaction of 1 occurred to form 2 or 2 and 3, respectively.
Thermokinetic study on the reversible competitive inhibition of bovine liver arginase
Authors: Xie Xiu‐Yin , Wang Cun‐Xin , Wang Zhi‐Yong
Published: September 2010

A new thermokinetic reduced extent method for studying of the reversible Competitive inhibition of single substrate enzyme‐catalyzed reactions was proposed in this paper. The reaction that arginase‐catalyzed hydrolysis of L‐arginine to L‐ornithine and urea and the inhibition of this reaction by the product, L‐ornithine, and exogenous L‐lysine were studied at 37 °C in 40 mmol−L−1 sodium barbiturate‐HC1 buffer solution (pH=9.4). Michealis constant Km for arginine and maximum velocity Vm of the reaction were determined to be 5.14 mmol.L−1 and 1.13X 10−‐2 mmol‐L−1.s‐1, respectively. The product inhibition constant Kp and inhibitory constant K1 of L‐lysine were determined to be 1.18 and 5.6 mmol.L−1, respectively. All the results have better repeatability and self‐consistency and are in agreement with literature values. This new method using more direct thermal information from the process would give more reliable kinetic information than the traditional initial rate method.
Reaction of molybdenum hexa‐carbonyl with mercapto‐pyridine (PySH) or mercapto‐pyridine oxide (PyS→O) and crystal structure of [Et4N][Mo2(PyS)3(CO)5]
Authors: Zhuang Bo‐Tao , Yu Pei‐Hua , Huang Liang‐Ren , He Ling‐Jie , Zhou Zhang‐Feng , Wu Ke‐Chen
Published: September 2010

Mixed‐valence dinuclear molybdenum complex [Et4N][ Mo2(PyS)3(CO)5] (1) (PyS=C5H4NS) has been synthesized and characterized by crystallography. 1 crystallizes in monoclinic system with space group P21/c with a= 1.5769(11) nm, b= 1.3144(5) nm, c= 1.6935(10) nm; β= 111.20(4)o; V=3.2724 nm3; Z=4, Dc=l.61 g/cm3, μ= 9.7 cm−' and F(000)=1600. The final R=0.054 and wR=0.073, for 1811 observed reflection with I >3@I). In compound 1, one chelating PyS ligand and two bridging PyS ligands are 3‐electron and 5‐electron donors, respectively, and two molybdenum atoms are located in different coordination environments resulting in mixed‐valence state. The reaction mechanism of Mo(CO)6 with PySH and PyS→O (C5H5SN→O) was investigated and two reaction pathways were proposed.
Formation of nanographite using GaPO4‐LTA as template
Authors: Xi Chun‐Yu , Li Guo‐Dong , Zhao Xu , Tian Ye , Zhang Yu , Chen Jie‐Sheng
Published: September 2010

An attempt was made to prepare nanographite with uniform size by pyrolysis of 4‐methyl pyridine (MPy), which is the structure‐directing agent for the formation of GaPO4‐LTA single crystals, in the GaPO4‐LTA framework at 760°C. The as‐prepared nanographite has been examined by Raman spectroscopy, transmission electron microscopy (TEM), electron spin resonance (ESR) and magnetization characterizations. The TEM image shows that the size of individual nanographite particles is about 7 nm, and it is proved that there are spins of sp2‐type (π‐type) radical electrons localized on the zigzag edge sites of the nanographite. The magnetic susceptibility of the nanographite shows crossover from a high‐temperature diamagnetic to a low‐temperature paramagnetic behavior, in good agreement with the theoretical expectation.
Molecular predictors of outcome in a phase 3 study of gemcitabine and erlotinib therapy in patients with advanced pancreatic cancer
Authors: da Cunha Santos Gilda , Dhani Neesha , Tu Dongsheng , Chin Kayu , Ludkovski Olga , Kamel‐Reid Suzanne , Squire Jeremy , Parulekar Wendy , Moore Malcolm J. , Tsao Ming Sound
Published: September 2010

BACKGROUND:

National Cancer Institute of Canada Clinical Trials Group PA.3 (NCIC CTG PA.3) was a phase 3 study (n = 569) that demonstrated benefits for overall survival and progression‐free survival with the addition of the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) erlotinib to gemcitabine in patients with advanced pancreatic carcinoma (APC). Mutation status of the v‐Ki‐ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) and EGFR gene copy number (GCN) were evaluated as predictive markers in 26% of patients who had tumor samples available for analysis.

METHODS:

KRAS mutation status was evaluated by direct sequencing of exon 2, and EGFR GCN was determined by fluorescence in situ hybridization (FISH) analysis. The results were correlated with survival, which was the primary endpoint of the trial.

RESULTS:

KRAS analysis was successful in 117 patients, and EGFR FISH analysis was successful in 107 patients. KRAS mutations were identified in 92 patients (78.6%), and EGFR amplification or high polysomy (FISH‐positive results) was identified in 50 patients (46.7%). The hazard ratio of death between gemcitabine/erlotinib and gemcitabine/placebo was 0.66 (95% confidence interval [CI], 0.28‐1.57) for patients with wild‐type KRAS and 1.07 (95% CI, 0.68‐1.66) for patients with mutant KRAS (P value for interaction = .38), and the hazard ratio was 0.6 (95% CI, 0.34‐1.07) for FISH‐negative patients and 0.90 (95% CI, 0.49‐1.65) for FISH‐positive patients (P value for interaction = .32).

CONCLUSIONS:

In a molecular subset analysis of patients from NCIC CTG PA.3, EGFR GCN and KRAS mutation status were not identified as markers predictive of a survival benefit from the combination of erlotinib with gemcitabine for the first‐line treatment of APC. Cancer 2010. © 2010 American Cancer Society.
First‐line chemotherapy with capecitabine and temozolomide in patients with metastatic pancreatic endocrine carcinomas
Authors: Strosberg Jonathan R. , Fine Robert L. , Choi Junsung , Nasir Aejaz , Coppola Domenico , Chen Dung‐Tsa , Helm James , Kvols Larry
Published: September 2010

BACKGROUND.

Temozolomide is an active agent in metastatic pancreatic endocrine carcinomas. In vitro data indicate that the combination of capecitabine and temozolomide is synergistic for induction of apoptosis in neuroendocrine tumor cell lines. The authors retrospectively evaluated the efficacy of capecitabine and temozolomide in 30 patients with metastatic pancreatic endocrine carcinomas to assess response rate, progression free survival (PFS), and overall survival (OS).

METHODS.

Patients with metastatic, well, or moderately differentiated pancreatic endocrine carcinomas who had not received prior systemic chemotherapy were treated with capecitabine (750 mg/m2 twice daily, days 1‐14) and temozolomide (200 mg/m2 once daily, days 10‐14) every 28 days.

RESULTS.

Among 30 patients treated, 21 (70%) patients achieved an objective radiographic response. Median progression‐free survival was 18 months. The rate of survival at two years was 92%. Only 4 patients (12%) experienced grade 3 or 4 adverse events.

CONCLUSIONS.

The combination of capecitabine and temozolomide is associated with an exceptionally high and durable response rate in metastatic endocrine carcinomas of the pancreas. Clinical endpoints, including response rate, survival, and toxicity, are superior to those observed with streptozocin‐based regimens Cancer 2011. © 2010 American Cancer Society.
Optimizing communication for Charm++ applications by reducing network contention
Authors: Bhatelé Abhinav , Bohm Eric , Kalé Laxmikant V.
Published: September 2010

Optimal network performance is critical for efficient parallel scaling of communication‐bound applications on large machines. No‐load latencies do not increase significantly with the number of hops traveled when wormhole routing is deployed. Yet, we and others have recently shown that in the presence of contention, message latencies can grow substantially large. Hence, task mapping strategies should take the topology of the machine into account on large machines. In this paper, we present topology aware mapping as a technique to optimize communication on three‐dimensional mesh interconnects and hence improve the performance. Our methodology is facilitated by the idea of object‐based decomposition used in Charm++ which separates the processes of decomposition from mapping of computation to processors and allows a more flexible mapping based on communication patterns between objects. Exploiting this and the topology of the allocated job partition, we present mapping strategies for a production code, OpenAtom to improve the overall performance and scaling. OpenAtom presents complex communication scenarios of interaction involving multiple groups of objects and makes the mapping task a challenge. Results are presented for OpenAtom on up to 16 384 processors of Blue Gene/L, 8192 processors of Blue Gene/P and 2048 processors of Cray XT3. Copyright © 2010 John Wiley & Sons, Ltd.
Cath6, a bHLH atonal family proneural gene, negatively regulates neuronal differentiation in the retina
Authors: Kubo Fumi , Nakagawa Shinichi
Published: September 2010

Basic helix–loop–helix (bHLH) transcription factors play important roles in cell type specification and differentiation during the development of the nervous system. In this study, we identified a chicken homolog of Atonal 8/ath6 (Cath6) and examined its role in the developing retina. Unlike other Atonal‐family proneural genes that induce neuronal differentiation, Cath6 was expressed in stem cell‐like progenitor cells in the marginal region of the retina, and its overexpression inhibited neuronal differentiation. A Cath6 fused with a VP16 transactivation domain recapitulated the inhibitory effect of Cath6 on neuronal differentiation, indicating that Cath6 functions as a transcription activator. These results demonstrate that Cath6 constitutes a unique member of the Atonal‐family of genes in that it acts as a negative regulator of neuronal differentiation. Developmental Dynamics 239:2492–2500, 2010. © 2010 Wiley‐Liss, Inc.
Neuron‐specific expression of atp6v0c2 in zebrafish CNS
Authors: Chung Ah‐Young , Kim Myoung‐Jin , Kim Dohyun , Bang Sangsu , Hwang Sun Wook , Lim Chae Seung , Lee Sanggyu , Park Hae‐Chul , Huh Tae‐Lin
Published: September 2010

Vacuolar ATPase (V‐ATPase) is a multi‐subunit enzyme that plays an important role in the acidification of a variety of intracellular compartments. ATP6V0C is subunit c of the V0 domain that forms the proteolipid pore of the enzyme. In the present study, we investigated the neuron‐specific expression of atp6v0c2, a novel isoform of the V‐ATPase c‐subunit, during the development of the zebrafish CNS. Zebrafish atp6v0c2 was isolated from a genome‐wide analysis of the zebrafish mibta52b mutant designed to identify genes differentially regulated by Notch signaling. Whole‐mount in situ hybridization revealed that atp6v0c2 is expressed in a subset of CNS neurons beginning several hours after the emergence of post‐mitotic neurons. The ATP6V0C2 protein is co‐localized with the presynaptic vesicle marker, SV2, suggesting that it is involved in neurotransmitter storage and/or secretion in neurons. In addition, the loss‐of‐function experiment suggests that ATP6V0C2 is involved in the control of neuronal excitability. Developmental Dynamics 239:2501–2508, 2010. © 2010 Wiley‐Liss, Inc.
Specific isoforms of Drosophila shroom define spatial requirements for the induction of apical constriction
Authors: Bolinger Cory , Zasadil Lauren , Rizaldy Ryan , Hildebrand Jeffrey D.
Published: September 2010

The Drosophila Shroom protein, dShrmA, induces apical constriction when ectopically expressed in the embryonic ectoderm. An embryo expressing dShrmA in the dorsal ectoderm was stained to detect dShrm (green) and F‐actin (red). Inset shows a scanning electron micrograph of a similar staged embryo also expressing dShrmA in the dorsal ectoderm. From Bolinger et al., Developmental Dynamics 239:2078–2093, 2010.
Brain expression of Cre recombinase driven by pancreas‐specific promoters
Authors: Song Junghun , Xu Yuanzhong , Hu Xiaoxia , Choi Brian , Tong Qingchun
Published: September 2010

Cre‐loxP technology enables specific examination of the function and development of individual nuclei in the complex brain network. However, for most brain regions, the utilization of this technique has been hindered by the lack of mouse lines with Cre expression restricted to these regions. Here, we identified brain expressions of three transgenic Cre lines previously thought to be pancreas‐specific. Cre expression driven by the rat‐insulin promoter (Rip‐Cre) was found mainly in the arcuate nucleus, and to a lesser degree in other hypothalamic regions. Cre expression driven by the neurogenin 3 promoter (Ngn3‐Cre mice) was found in the ventromedial hypothalamus. Cre expression driven by the pancreas‐duodenum homeobox 1 promoter (Pdx1‐Cre) was found in several hypothalamic nuclei, the dorsal raphe and inferior olivary nuclei. Interestingly, Pdx1‐Cre mediated deletion of vesicular GABA transporter led to postnatal growth retardation while Ngn3‐Cre mediated deletion had no effects, suggesting a role for Pdx1‐Cre neurons, but not pancreas, in the regulation of postnatal growth. These results demonstrate the potential for these Cre lines to study the function and development of brain neurons. genesis 48:628–634, 2010. © 2010 Wiley‐Liss, Inc.
High‐bandwidth design of hard disk control system using H∞ control with feedback‐type uncertainty
Authors: Hirata Mitsuo , Hasegawa Yumi
Published: September 2010

In hard disk drives, it is important to enlarge the control bandwidth in order to shorten the track pitch for larger data capacity. However, it is difficult for the H∞ control method to increase the control bandwidth if the mechanical resonance modes have uncertainty. This is because the robustness of the H∞ control method is assured by the small‐gain theorem for additive or multiplicative perturbation and the control bandwidth is limited by the uncertainty. In this study, we propose an H∞ control method for high‐bandwidth design by introducing a new uncertainty model with a feedforward and a feedback path in order to reduce the conservatism of robust design. The effectiveness is shown by numerical simulations. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 173(4): 54–62, 2010; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21025
Reactions of [Re(CO)3]+ with Histidylhistidine and Modified Histidines (Eur. J. Inorg. Chem. 25/2010)
Authors: Herrick Richard S. , Ziegler Christopher J. , Gambella Americo
Published: September 2010

The cover picture shows the crystal structures of two complexes that were prepared from aqueous reactions of histidine‐based ligands with Re(CO)3(H2O)3+ and serve as models of 99mTc(CO)3+/His‐tag protein complexes. The complexes, similar to those found in certain enzymes, show unexpected peptide carboxamido‐N donor bonds that underscore the stability of the labeled His‐tag proteins as discussed in the Short Communication by R. S. Herrick, C. J. Ziegler et al. on p. 3905 ff. Artwork: Christopher J. Ziegler.
A General and Highly Efficient Method for the Construction of Aryl‐Substituted N‐Heteroarenes
Authors: Liu Chun , Han Na , Song Xiaoxiao , Qiu Jieshan
Published: September 2010

A general, simple and highly efficient method has been developed for the Pd(OAc)2‐catalyzed ligand‐free and aerobic Suzuki reaction of N‐heteroaryl halides, which is strongly dependent on the molecular structure of solvent.
Facilitated Transfer of Alkali and Alkaline‐Earth Metal Ions by a Calix[4]arene Derivative Across Water/1,2‐Dichloroethane Microinterface: Amperometric Detection of Ca2+
Authors: Bingol Haluk , Kaykal Ferhat , Akgemci Emine G. , Sirit Abdulkadir
Published: September 2010

The host–guest complexation reactions between 5,11,17,23‐tetra‐tert‐butyl‐25,27‐diethoxycarbonylmethoxy‐26,28‐dimethoxy calix[4]arene (BDDC4) and alkali and alkaline‐earth metal ions were investigated by facilitated ion transfer processes across water/1,2‐dichloroethane microinterface by using steady‐state cyclic voltammetry and differential pulse voltammetry. The obtained facilitated transfers for Li+, Na+, K+, Rb+ and Ca2+ were evaluated under the different experimental conditions, at the excess concentrations of metal ions with respect to BDDC4 and vice versa. The association constants having 1 : 1 stoichiometry for Li+, Na+, K+ and Rb+ in 1,2‐DCE were determined. Also, we demonstrated that BDDC4 can play an important role for the development of highly selective chemical sensor for Ca2+ among alkaline‐metal ions in the concentration range of 0.1–1.0 mM in aqueous solution.
Determination of Lead in Ambient Aerosol Samples by Anodic Stripping Voltammetry on a Bismuth Film Electrode
Authors: Marín Mª Rosario Palomo , Gil Eduardo Pinilla , Blázquez Lorenzo Calvo
Published: September 2010

Cd and Pb determination in ambient aerosol samples based on SWASV at a Bi film glassy carbon electrode is described. Extremely acid solutions resulting from sample digestion were directly assayed, with sufficient detection limits for testing the fulfilment of air quality regulations. Accuracy was tested on NIST Standard Reference Materials and real aerosol samples, with good recoveries for Pb comparable to ICP‐MS results. Cd was not detected, probably due to the combined effects of low Cd and high interfering Zn and Cu contents. The proposed method provides an attractive alternative to ICP‐MS with potential applicability for decentralized analysis.
Optical features of the fluorophore azotobactin: Applications for iron sensing in biological fluids
Authors: Sharma Manisha , Gohil Nivedita Karmakar
Published: September 2010

Siderophores are bio‐organic ligands secreted by microbes to chelate and assimilate iron to meet their metabolic requirements. Siderophores and their analogs have tremendous therapeutic and analytical potential including the use as Fe (III) biosensors; however, only few practical applications have been realized. The aim of this study was the optical and biophysical characterization of the siderophore azotobactin (Az) secreted by the nitrogen‐fixing bacteria Azotobacter vinelandii. The peptide exhibited fluorescence in the visible range. Quantum yield and lifetime in excited state were measured to ascertain the sensitivity of the molecule as a fluorescent marker in biochemical assays. Its high affinity toward iron in the ferric state was demonstrated through fluorescence emission quenching studies. The accuracy of azotobactin as biosensing tool was determined by analyzing the levels of iron in biological fluids, particularly in human serum. Furthermore, it was demonstrated that it can be encapsulated in sol–gel matrices without significant loss of its fluorescence signal, thus enabling it suitable for adaptation to optical biosensor for Fe (III).
Dementia services in Canada
Authors: Rockwood Kenneth , Keren Ron
Published: September 2010

Canadians with dementia have access to Medicare, a universal, single payer healthcare program. Implementation of Medicare is through the provinces and territories, giving variation in the level of care available. At present, there is no national strategy for dementia, although a recent report from the Alzheimer Society of Canada is expected to catalyze one. Most dementia care is provided by primary care practitioners, with three specialties (geriatric psychiatry, geriatric medicine and neurology) providing consultant expertise. Primary care reforms are aimed at developing a more coordinated approach to the complex needs of people with dementia, and have especially emphasized education of providers. Any national strategy is expected to underscore prevention and research, the latter building on Canada's strong contribution to this international undertaking. Copyright © 2010 John Wiley & Sons, Ltd.
Malnutrition and quality of life in patients treated for oral or oropharyngeal cancer
Authors: Jager‐Wittenaar Harriët , Dijkstra Pieter U. , Vissink Arjan , van der Laan Bernard F. A. M. , van Oort Rob P. , Roodenburg Jan L. N.
Published: September 2010

Background.

This study assessed whether malnourished patients score lower on quality of life after treatment for oral/oropharyngeal cancer.

Methods.

Malnutrition (weight loss ≥10% in 6 months/≥5% in 1 month) and quality of life (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 questionnaire) were assessed cross‐sectionally in patients treated for oral/oropharyngeal cancer. The interval after treatment varied from 1 day to 3 years. The relationship between malnutrition and quality of life was analyzed univariately (Mann–Whitney U test) and multivariately (linear regression analyses). Statistical significance was set at p < .05.

Results.

Prevalence of posttreatment malnutrition was 16% (18/115, 95% confidence interval [CI]: 9% to 23%). Analyzed univariately, malnourished patients scored significantly worse on physical functioning (p = .007) and fatigue (p = .034) than well‐nourished patients. Multivariate analysis revealed that malnutrition was significantly related to physical functioning (p = .015).

Conclusions.

Malnourished patients treated for oral/oropharyngeal cancer score lower on quality of life scales related to physical fitness. © 2010 Wiley Periodicals, Inc. Head Neck, 2011
Cysteinyl leukotriene receptor expression pattern affects migration of breast cancer cells and survival of breast cancer patients
Authors: Magnusson Cecilia , Liu Jian , Ehrnström Roy , Manjer Jonas , Jirström Karin , Andersson Tommy , Sjölander Anita
Published: September 2010

The fact that breast cancer patients with local or distal dissemination exhibit decreased survival, promotes a search for novel mechanisms to suppress such tumor progression. Here, we have determined the expression of proinflammatory cysteinyl leukotriene receptors (CysLTRs) in breast tumor tissue and their signaling effect on breast cancer cell functions related to tumor progression. Patients with breast tumors characterized by high CysLT1R and low CysLT2R expression levels exhibited increased risk of cancer‐induced death in univariate analysis for both the total patient group (hazard ratio [HR] = 2.88, 95% confidence interval [CI] = 1.11–7.41), as well as patients with large (>20 mm) tumors (HR = 5.08, 95% CI = 1.39–18.5). Multivariate analysis revealed that patients with large tumors exhibiting high CysLT1R and low CysLT2R expression levels had a significantly reduced survival, also when adjusted for established prognostic parameters (HR = 7.51, 95% CI = 1.83–30.8). In patients with large (>20 mm) tumors, elevated CysLT2R expression predicted an improved 5‐year survival (log‐rank test p = 0.04). Surprisingly, for longer time periods, this prognostic value was lost. This disappearance coincided with the termination of hormonal treatment. Tamoxifen preserved and even induced transcription of CysLT2R, but not CysLT1R, in estrogene receptor‐positive MCF‐7 breast cancer cells. This elevated CysLT2R expression decreased, even below the level of untreated cells, when tamoxifen was withdrawn. CysLT2R signaling reduced MCF‐7 cell migration, but had no effect on either proliferation or apoptosis. Our data indicate that low CysLT1R together with high CysLT2R expression levels might be useful parameters in prognostication and treatment stratification of breast cancer patients.
Electrospun cross‐linked gelatin fibers with controlled diameter: The effect of matrix stiffness on proliferative and biosynthetic activity of chondrocytes cultured in vitro
Authors: Skotak Maciej , Noriega Sandra , Larsen Gustavo , Subramanian Anuradha
Published: September 2010

Nanofibrous scaffolds were prepared from gelatin solutions and were further cross‐linked with glutaraldehyde (GA). The fiber diameter was varied from 100 to 1000 nm by controlling the applied voltage (4–15 kV) and the concentration of the gelatin solution (4–15%). The tensile moduli and the tensile strength of the noncross‐linked scaffolds varied from 20 to 120 MPa and 0.5 to 3.5 MPa, respectively. Cross‐linking with GA led to an increase in both the tensile modulus and strength and correlated with cross‐linker concentration. Gelatin‐based matrices were characterized by Fourier transform infrared spectroscopy and differential scanning calorimetry. High cellular viabilities and rounded morphology of chondrocytes was observed at the end of 7 days in culture with added matrix deposition and flattening of cells at 15 days. Matrix stiffness was noted to impact cell densities and the expression of chondrocytic markers, especially aggrecan. The ratios of collagen‐II (C‐II) to collagen‐I (C‐I) of 0.62 and 1.33 were noted on gelatin nanofibrous scaffolds cross‐linked with 0.1% GA at the end of 7 and 15 days in culture, respectively. C‐II/C‐I ratios of 1.30 and 2.58 were noted on scaffolds cross‐linked with 1.0% GA at the end of 7 and 15 days in culture, respectively. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
Differential mechanisms for the inhibition of human cytochrome P450 1A2 by apigenin and genistein
Authors: Shimada Hideaki , Eto Masashi , Ohtaguro Misa , Ohtsubo Michihiro , Mizukami Yosuke , Ide Tsuyoshi , Imamura Yorishige
Published: September 2010

The inhibitory effects of flavonoids on the human cytochrome P450 1A2 (CYP1A2) were examined. Among flavonoids tested, galangin, kaempferol, chrysin, and apigenin were potent inhibitors. Although apigenin belonging to flavones and genistein belonging to isoflavones are similar in the chemical structures, the inhibitory potencies for CYP1A2 were distinguished markedly between these two flavonoids. In computer‐docking simulation, apigenin interacted with the same mode of cocrystallized α‐naphthoflavone in the active site of CYP1A2, and then the B ring of apigenin was placed close to the heme iron of the enzyme with a single orientation. In contrast, the docked genistein conformation showed two different binding modes, and the A ring of genistein was oriented to the heme iron of CYP1A2. Furthermore, the binding free energy of apigenin was lower than that of genistein. These results demonstrate a possible mechanism that causes the differential inhibitory potencies of apigenin and genistein for CYP1A2. © 2010 Wiley Periodicals, Inc. J Biochem Mol Toxicol 24:230–234, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20328
How to transition from assessing performance to enhancing performance with balanced scorecard goal action plans
Authors: Albright Thomas L. , Burgess Christopher M. , Hibbets Aleecia R. , Roberts Michael L.
Published: September 2010

The balanced scorecard (BSC) has achieved widespread acceptance as a strategic performance measurement tool. This article builds on the BSC process by showing how goal action plans can be used to help organizations translate strategic goals into actionable employee behavior to improve bottom‐line performance. © 2010 Wiley Periodicals, Inc.
A Raman spectroscopic study of copiapites Fe2+Fe3+(SO4)6(OH)2 · 20H2O: environmental implications
Authors: Frost Ray L.
Published: September 2010

Raman spectroscopy has been used to study selected mineral samples of the copiapite group. Copiapite (Fe2+Fe3+(SO4)6(OH)2 · 20H2O) is a secondary mineral formed through the oxidation of pyrite. Minerals of the copiapite group have the general formula AFe4(SO4)6(OH)2 · 20H2O, where A has a + 2 charge and can be either magnesium, iron, copper, calcium and/or zinc. The formula can also be B2/3Fe4(SO4)6(OH)2 · 20H2O, where B has a + 3 charge and may be either aluminium or iron. For each mineral, two Raman bands are observed at around 992 and 1029 cm−1, assigned to the (SO4)2−ν1 symmetric stretching mode. The observation of two bands provides evidence for the existence of two non‐equivalent sulfate anions in the mineral structure. Three Raman bands at 1112, 1142 and 1161 cm−1 are observed in the Raman spectrum of copiapites, indicating a reduction of symmetry of the sulfate anion in the copiapite structure. This reduction in symmetry is supported by multiple bands in the ν2 and ν4(SO4)2− spectral regions. Copyright © 2010 John Wiley & Sons, Ltd.
Arbitrage between capital sources in entrepreneurial firms: a foreword note
Authors: Kianfar Michael , Milana Carlo , Smith Helen Lawton
Published: September 2010

Firms born to grow could find their way successfully no matter how harsh the external financial conditions seem to be.
Venture capital syndication and its causal relationship with performance outcomes
Authors: Checkley Matthew , Higón Dolores Añón , Angwin Duncan
Published: September 2010

Venture capital firms benefit from frequent and diverse syndication ties; these are causal of increased IPO generation.
Intellectual property governance and the pursuit of economic rewards in UK universities
Authors: Andersen Birgitte , Rossi Federica
Published: September 2010

Universities can obtain economic rewards not only by commercializing intellectual property embedded in patents, but also by sharing open access knowledge.
Ultrasound‐guided needle aspiration: Impact of immediate cytologic review
Authors: Moberly Aaron C. , Vural Emre , Nahas Bari , Bergeson Tonya R. , Kokoska Mimi S.
Published: September 2010

Objectives/Hypothesis:

To compare the diagnostic adequacy of ultrasound‐guided fine‐needle aspiration biopsy (USFNA) of the head and neck with immediate on‐site microscopic evaluation and feedback by a cytopathologist (IMMEDIATE) versus delayed examination without immediate feedback (DELAYED).

Study Design:

Retrospective chart review of office‐based USFNA performed in both IMMEDIATE and DELAYED settings by the same otolaryngologist.

Methods:

A total of 199 USFNA procedures in the head and neck were performed by one practitioner. Of these procedures, 137 biopsies were performed in the DELAYED setting, whereas 62 biopsies were performed in the IMMEDIATE setting. Cytopathology reports were reviewed for diagnostic conclusions as well as adequacy of biopsies. The results from both settings were compared using Pearson χ2 test.

Results:

The ability to obtain a diagnosis from USFNA was 73.0% in the DELAYED group as compared with 90.3% in the IMMEDIATE group. The rate of adequate cells on biopsy was 89.1% in the DELAYED group as compared with 96.8% in the IMMEDIATE group. There was a statistically significant difference between observed and expected diagnostic rates (χ2[1] = 7.568, P = .006) and a trend toward a significant difference between the observed and expected adequacy rates (χ2[1] = 3.259, P = .071) when IMMEDIATE evaluation by a cytopathologist was performed.

Conclusions:

An immediate microscopic evaluation of USFNA specimens to confirm adequacy of sampling is strongly recommended. Diagnostic conclusions were increased when an evaluation of the specimen was performed at the time of biopsy. The specimen adequacy rate tended to increase with an immediate cytopathologic assessment. Laryngoscope, 2010
Balloon catheter technology in rhinology: Reviewing the Evidence
Authors: Batra Pete S. , Ryan Matthew W. , Sindwani Raj , Marple Bradley F.
Published: September 2010

Balloon catheter technology (BCT) for management of paranasal sinus inflammatory disease was introduced to otolaryngology in 2005. Since its introduction, BCT has been a subject of considerable controversy with proponents for and against adoption of the technology. Balloon procedures have been promoted as a less invasive alternative to endoscopic sinus surgery that results in reduced pain and quicker recovery. The technology and its promotion have generated significant press coverage and interest by the lay public looking for new solutions for sinonasal problems. Over time, alternate balloon devices have been advocated for operating room and office‐based sinus ostia dilatation. This contemporary review will evaluate the existing evidence on the available balloon devices. The frank strengths and weaknesses of the peer‐reviewed literature will be highlighted. The potential complications unique to balloon catheters and radiation exposure from fluoroscopy will also be discussed. Laryngoscope, 2011
GreenLight HPS laser 120‐W versus diode laser 200‐W vaporization of the prostate: Comparative clinical experience
Authors: Chiang Po Hui , Chen Chien Hsu , Kang Chih Hsiung , Chuang Yao Chi
Published: September 2010

Background and Objective

We present our clinical experiences of two recently introduced vaporization laser systems: the GreenLight High Performance System (HPS) laser (532 nm, 120 W) and the Diolas LFD diode laser (980 nm, 200 W).

Materials and Methods

Two laser systems were evaluated to compare their clinical results for the treatment of benign prostatic hyperplasia (BPH). Patients were treated using either the GreenLight HPS laser (n = 84) or the diode laser (n = 55) in a prospective randomized study. The data of International Prostate Symptom Score (IPSS), maximum flow rate (Qmax), post‐void residual urine (PVR), and quality of life score (Qols) were recorded at baseline, 1‐, 6‐, and 12‐month follow‐ups. The prostate volume and prostate‐specific antigen (PSA) level were assessed at baseline and 6‐month follow‐up. All complications were also recorded.

Results

There was a statistically significant difference in IPSS, Qmax, PVR, and QoLs in each laser group at the 1‐, 6‐, and 12‐month follow‐ups compared with baseline. There was no statistical significant difference in any of these parameters at any follow‐up interval between each group. The diode laser demonstrates superior hemostatic properties compared with the GreenLight HPS laser. Postoperative incontinence and postoperative irritative symptoms are more pronounced (P < 0.05) after diode laser prostatectomy. Higher incidence of dysuria with sloughing tissues and epididymitis (P < 0.05) is noted after diode laser prostatectomy. Other complications were comparable for both procedures.

Conclusions

Although both lasers can improve subjective and objective parameters of BPH, both can produce undesired effects. The search for the ideal vaporization laser to treat BPH still continues. Lasers Surg. Med. 42:624–629, 2010. © 2010 Wiley‐Liss, Inc.
Increasing the efficiency of photodynamic therapy by improved light delivery and oxygen supply using an anticoagulant in a solid tumor model
Authors: Yang Liyong , Wei Yanchun , Xing Da , Chen Qun
Published: September 2010

Background and Objective

The main factors in photodynamic therapy (PDT) are: photosensitizer retention, photon absorption, and oxygen supply. Each factor has its unique set of problems that poses limitation to the treatment. Both light delivery and oxygen supply are significant bottlenecks in PDT. Vascular closure during PDT reduces oxygen supply to the targeted tissue. On the other hand, with the changes in blood perfusion, the tissue optical properties change, and result in variation in irradiation light transmission. For these reasons, it becomes very important to avoid blood coagulation and vascular closure during PDT.

Study Design/Materials and Methods

The efficiency of PDT combined with the anticoagulant heparin was studied in a BALB/c mouse model with subcutaneous EMT6 mammary carcinomas. Mice were randomized into three groups: control, PDT‐only, and PDT with heparin. The photosensitizer Photofrin® was used in our experiments. Light transmission, blood perfusion, and local production of reactive oxygen species (ROS) were monitored during the treatment. The corresponding histological examinations were performed to determine the thrombosis immediately after irradiation and to evaluate tumor necrosis 48 hours after the treatment.

Results

The results clearly demonstrated that PDT combined with pre‐administered heparin can significantly reduce thrombosis during light irradiation. The blood perfusion, oxygen supply, and light delivery are all improved. Improved tumor responses in the combined therapy, as shown with the histological examination and tumor growth assay, are clearly demonstrated and related to an increased local ROS production.

Conclusion

Transitory anticoagulation treatment significantly enhances the antitumor effect of PDT. It is mainly due to the improvement of the light delivery and oxygen supply in tumor, and ultimately the amount of ROS produced during PDT. Lasers Surg. Med. 42:671–679, 2010. © 2010 Wiley‐Liss, Inc.
Enhanced Thermal Diffusivity by Vertical Double Percolation Structures in Polyimide Blend Films Containing Silver Nanoparticles
Authors: Yorifuji Daisuke , Ando Shinji
Published: September 2010

The thermal diffusivity along the out‐of‐plane direction (D⟂) in polyimide (PI) blend films containing silver nanoparticles (Ag‐NPs) was investigated. PI blend films composed of a sulfur‐ and a fluorine‐containing PI were prepared via spin‐coating and thermal curing of the precursor solutions dissolving silver nitrate. Micro‐phase‐separated structures with a “vertical double percolation (VDP)” morphology were spontaneously formed in the films, in which two phases are separately aligned along the out‐of‐plane direction, and Ag‐NPs were preferentially precipitated in the sulfur‐containing PI phase. The blend films exhibited higher D⟂ values than monophase PI films containing homogeneously dispersed Ag‐NPs. These results indicate that the VDP structure functions as an effective thermal conductive pathway.

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“Tree‐Shaped” Copolymers Based on Poly(ethylene glycol) and Atactic or Isotactic Polylactides: Synthesis and Characterization
Authors: Izzo Lorella , Pappalardo Daniela
Published: September 2010

“Tree‐shaped” copolymers constituted by an m‐PEG trunk and poly(L‐lactide) or poly(D,L‐lactide) branches were obtained. The m‐PEG was functionalized at the terminal chain with two (G1) and four (G2) hydroxyl groups, then reacted with Al(CH3)3 to produce aluminum alkoxide species, active as initiators in the ROP of L‐ or D,L‐lactide. Copolymers were characterized by 1H and 13C NMR, GPC and DSC, and compared with analogous linear copolymers. Characterization of a low‐molecular‐weight G1 copolymer confirmed the architecture. GPC curves showed monomodal and narrow molecular weight distribution for all the samples, while the melting points of the copolymers seemed more correlated to the architecture than to the composition.

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Alternating Poly(Pt‐salphen)‐(p‐phenyleneethynylene) as Phosphorescent Conjugated Linear‐Rod and Coilable Sensory Materials
Authors: Sun Shenmei , Tong Wah‐Leung , Chan Michael C.W.
Published: September 2010

Phosphorescent conjugated polymers consisting of alternating p‐phenylene‐ethynylene and ‘para‐’ or ‘meta‐type’ Pt(II)‐salphen luminophore units have been synthesized. Side‐arms bearing different substituents (n‐alkoxy and acetylated‐sugar) have afforded contrasting emission properties that are attributed to the polymer conformation, extent of π‐stacking interactions and differences in chemical structure. Intriguing selectivity in luminescent sensing of metal ions has been observed.

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Transparent, Versatile Chemical Vapor Sensor Using Supramolecular Assembly of Block Copolymer and Carbon Nanotubes
Authors: Kuila Biplab K. , Stamm Manfred
Published: September 2010

Here, a simple and novel approach is reported for developing a new class of transparent chemical vapor sensors with a low power consumption, high sensitivity, good selectivity, and excellent environmental stability by depositing multiwalled carbon nanotubes on prepatterned polymer substrates using supramolecular assembly. The patterned polymer substrates were fabricated from block copolymers, whereas the supramolecular assembly between the carbon nanotubes and block copolymer is utilized for the selective localization of carbon nanotubes at the block copolymer–air interface. The thin film devices made from the block copolymer and carbon nanotubes are highly transparent (transmittance > 90%) and respond to a wide range of solvents of different polarity, both hydrophilic and hydrophobic, with good selectivity and fast response time.

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