bluuebunny/crossref_metadata_2025 huggingface dataset:
TBA Production by Acid Hydrolysis of MTBE During Heated Headspace Analysis and Evaluation of a Base as a Preservative
Authors: McLoughlin Patrick W. , Pirkle Robert J. , Fine Dennis , Wilson John T.
Published: November 2010

At room temperature (20° ± 3°C), purge and trap samplers provide poor sensitivity for analysis of the fuel oxygenates that are alcohols, such as tertiary butyl alcohol (TBA). Because alcohols are miscible or highly soluble in water, they are not efficiently transferred to a gas chromatograph for analysis. To improve the efficiency of transfer, the water in a purge and trap sampler can be heated. Alternatively, the sensitivity for TBA can be improved by preparing the sample in a heated static headspace sampler. In a heated water sample, the acid used as a preservative may cause chemical hydrolysis of methyl tertiary butyl ether (MTBE) to produce TBA. This effect is well illustrated in this paper using data collected by the U.S. Environmental Protection Agency Office of Research and Development on a plume of MTBE in California. Samples were analyzed using a static head‐space sampler heated to 80°C. The ground water samples were preserved in the field with HCl to a pH ≤ 2. The extent of MTBE hydrolysis to TBA during sample analysis varied from 19% to 87%; the average extent of hydrolysis was 59%. To confirm and document the importance of acid hydrolysis of MTBE at higher temperatures during sample preparation, the rate of hydrolysis of MTBE was measured at 80°C. At pH = 1, the rate of hydrolysis was 1.22/h, while the rate at pH = 2 was 0.15/h. Acid hydrolysis of MTBE during sample preparation in a heated headspace sampler can be avoided by preserving the sample with 1% (w/w) trisodium phosphate dodecahydrate (TSP) instead of using HCl, or by neutralizing the acid before analysis. In the presence of an acclimated microbial culture, TSP prevented biodegradation of MTBE, as well as benzene, toluene, ethylbenzene, and xylene compounds, in ground water at room temperature for 66 d. However, in a spike recovery experiment, TSP caused based catalyzed hydrolysis of bromomethane. It is not appropriate as a universal preservative.
A New Complex Design for Air-Breathing Polymer Electrolyte Membrane Fuel Cells Aided by Rapid Prototyping
Authors: Chen Chen-Yu , Wen Yun-Che , Lai Wei-Hsiang , Chou Ming-Chang , Weng Biing-Jyh , Hsieh Ching-Yuan , Kung Chien-Chih
Published: November 2010

One of the most difficult issues to fabricate a fuel cell with a complex design is the manufacturing method. To solve this difficulty, the authors applied an innovative method of fuel cell fabrication, i.e., rapid prototyping technology. The rapid prototyping technology can both fabricate the complex design and shorten the fabrication time. In this paper, the authors used a 3D software (CATIA) on the fuel cell design and utilized the rapid prototyping to accelerate the prototype development of complex stack designs and to verify the practicability of the new fabrication for fuel cells. The honeycomb shape methanol reservoir and cathode structure design of a direct methanol fuel cell (DMFC) and the complex flow distributor design of a monopolar air-breathing proton exchange membrane fuel cell (PEMFC) stack, which were almost impossibly manufactured by traditional manufacturing, were made in this study. The performance of the traditional air-pumping DMFC and that of an air-breathing DMFC were compared in this study. The feasibility of a complex pseudobipolar design DMFC stack was also verified. For the miniature air-breathing PEMFC made by rapid prototyping with ABS material, its performance is close to the state-of-the-art compared to previous published literatures (Hsieh et al. 2006, “Study of Operational Parameters on the Performance of Micro PEMFCs With Different Flow Fields,” Energy Convers. Manage., 47, pp. 1868–1878; Schmitz, A., Wagner, S., Hahn, R., Uzun, H., and Hebling, C., 2004, “Stability of Planar PEMFC in Printed Circuit Board Technology,” J. Power Sources, 127, pp. 197–205; Hottinen, T., Mikkola, M., and Lund, P., 2004, “Evaluation of Planar Free-Breathing Polymer Electrolyte Membrane Fuel Cell Design,” J. Power Sources, 129, pp. 68–72). A new solution to manufacture complex fuel cell design, rapid prototyping, has been first applied to the fabrication of complicated flow channels in ABS materials and directly used in both DMFC and PEMFC in this paper. Its feasibility was verified and its promising performance was also proved.
Design, Optimization, and Fabrication of Slotted-Interdigitated Thin Metallic Bipolar Plates for PEM Fuel Cells
Authors: Peng Linfa , Lai Xinmin , Yi Peiyun , Mai Jianming , Ni Jun
Published: November 2010

Thin metallic sheet bipolar plates (BPPs) with sustainable coating are promising candidates to replace conventional graphitic or machined thick metal plates due to their lightweight and low cost. Interdigitated flow field design is easier for two stamped thin metallic sheets joined together to compose reactant flow fields in both sides and serpentine coolant flow field in the middle. Unfortunately, this kind of BPP inevitable brings two main defects: rupture of material during forming process and uneven flow distribution in practical operation. First, we propose a slotted-interdigitated configuration of the flow field for proton exchange membrane fuel cell with consideration of the characteristics of the metallic sheet forming process. In order to relieve the uneven flow distribution, an analytic model is introduced to analyze the reactant gas flow based on the similarity between the gas flow and the electrical current. Furthermore, an optimization model is proposed. The depth of the slot on the channel rib is optimized to eliminate the uneven flow distribution to obtain high reaction performance. Second, we studied the BPPs from the manufacturability perspective because it is also another important factor that should be considered in the design stage. The key geometric dimensions of flow field section, where the rupture occurs, are extracted and parametrized. Finite element analysis model is established to analyze the formability of BPP by flexible forming process (FFP). In addition, different dies with various flow channel sections are prepared and experiments are performed. Some design principles about material selection and key geometric dimension definition are proposed to improve the formability of BPPs. In the end, based on the design principles and experimental results, the dies are carefully design and fabricated experimental setup for FFP is prepared and practical experiments are performed. High quality metallic BPPs are achieved eventually by FFP.
Hydrophilic ePTFE-Based Composite Membranes for PEMFCs
Authors: Shi Jinjun , Jang Bor
Published: November 2010

A hydrophilic expanded poly(tetrafluoroethylene) (ePTFE) based composite membrane was prepared and tested for proton exchange fuel cell applications. The composite membrane was prepared by impregnating hydrophilic ePTFE membrane with 5% Nafion solution (equivalent weight=1000). This new composite membrane showed higher water uptake (12.7%) than that of normal hydrophobic ePTFE based composite membrane (6.3%) and better proton conductivity. Scanning electron microscopy micrographs showed that the hydrophilic ePTFE based membrane can easily form a dense composite membrane while hydrophobic ePTFE based composite membranes tend to have micropores inside. The hydrophilic ePTFE based composite membrane showed better thermal and dimensional stability than recast Nafion membrane.
A Numerical Model for Predicting Gas Diffusion Layer Failure in Proton Exchange Membrane Fuel Cells
Authors: Yi Peiyun , Peng Linfa , Lai Xinmin , Ni Jun
Published: November 2010

Gas diffusion layer (GDL) is one of the critical components in proton exchange membrane fuel cells (PEMFCs) and plays several important roles, such as structural support, reactants permeation, water removal, electrons, and heat conduction. The assembly pressure on bipolar plate is an important factor that affects the performance of PEMFC stack. Not enough assembly pressure leads to leakage of fuels and high contact resistance. Too much pressure, on the other hand, results in damage to the GDL, which increases the GDL Ohmic resistance and interfacial contact resistance, and in turn influences the reactant transport and water removal. The objective of the present study is to develop a numerical model to predict the onset of GDL failure and obtain the maximum assembly pressure on bipolar plate. Composite micromechanical model is applied to calculate the effective elastic properties of GDL; strength failure criterion is established to judge GDL damage with the stress distribution; finite element method model is developed to show the failure zone and the failure propagation in GDL combining the estimated elastic properties and strength failure criterion. Toray TGP-H-060 carbon paper is introduced as a numerical example and the numerical results show good agreements with experimental results. This numerical prediction model is beneficial to understand the basic mechanism of GDL failure and helpful to guide the assembling of PEMFC stack.
Convective Heat Transfer on a Rotating Disk With Transverse Air Crossflow
Authors: Latour Benjamin , Bouvier Pascale , Harmand Souad
Published: November 2010

In this study, the local convective heat transfer from a rotating disk with a transverse air crossflow was evaluated using an infrared thermographic experimental setup. Solving the inverse conduction heat transfer problem allows the local convective heat transfer coefficient to be identified. We used the specification function method along with spatio-temporal regularization to develop a model of local convective heat transfer in order to take lateral conduction and 2D geometry into account. This model was tested using rotational Reynolds numbers (based on the cylinder diameter and the peripheral speed) between 0 and 17,200 and air crossflow Reynolds numbers between 0 and 39,600. In this paper, the distribution of the local heat transfer on the disk allows us to observe the combined effect of the rotation and air crossflow on heat exchanges. This coupling is able to be taken into account in a correlation of mean Nusselt number relative to both Reynolds numbers.
Insights into Membrane Association of
Klebsiella pneumoniae
NifL under Nitrogen-Fixing Conditions from Mutational Analysis
Authors: Milenkov Maria , Thummer Robert , Glöer Jens , Grötzinger Joachim , Jung Sascha , Schmitz Ruth A.
Published: November 2010

In
Klebsiella pneumoniae
nitrogen fixation is tightly controlled in response to ammonium and molecular oxygen by the NifL/NifA regulatory system. Under repressing conditions, NifL inhibits the
nif
-specific transcriptional activator NifA by direct protein-protein interaction, whereas under anaerobic and nitrogen-limited conditions sequestration of reduced NifL to the cytoplasmic membrane impairs inhibition of cytoplasmic NifA by NifL. We report here on a genetic screen to identify amino acids of NifL essential for sequestration to the cytoplasmic membrane under nitrogen-fixing conditions. Overall, 11,500 mutated
nifL
genes of three independently generated pools were screened for those conferring a Nif
−
phenotype. Based on the respective amino acid changes of nonfunctional derivatives obtained in the screen, and taking structural data into account as well, several point mutations were introduced into
nifL
by site-directed mutagenesis. The majority of amino acid changes resulting in a significant
nif
gene inhibition were located in the N-terminal domain (N46D, Q57L, Q64R, N67S, N69S, R80C, and W87G) and the Q-linker (K271E). Further analyses demonstrated that positions N69, R80, and W87 are essential for binding the FAD cofactor, whereas primarily Q64 and N46, but also Q57 and N67, appear to be crucial for direct membrane contact of NifL under oxygen and nitrogen limitation. Based on these findings, we propose that those four amino acids most likely located on the protein surface, as well as the presence of the FAD cofactor, are crucial for the correct overall protein conformation and respective surface charge, allowing NifL sequestration to the cytoplasmic membrane under derepressing conditions.
The Atypical OmpR/PhoB Response Regulator ChxR from
Chlamydia trachomatis
Forms Homodimers
In Vivo
and Binds a Direct Repeat of Nucleotide Sequences
Authors: Hickey John M. , Weldon Lindsey , Hefty P. Scott
Published: November 2010

Two-component signal transduction systems are widespread in bacteria and are essential regulatory mechanisms for many biological processes. These systems predominantly rely on a sensor kinase to phosphorylate a response regulator for controlling activity, which is frequently transcriptional regulation. In recent years, an increasing number of atypical response regulators have been discovered in phylogenetically diverse bacteria. These atypical response regulators are not controlled by phosphorylation and exhibit transcriptional activity in their wild-type form. Relatively little is known regarding the mechanisms utilized by these atypical response regulators and the conserved characteristics of these atypical response regulators.
Chlamydia
spp. are medically important bacteria and encode an atypical OmpR/PhoB subfamily response regulator termed ChxR. In this study, protein expression analysis supports that ChxR is likely exerting its effect during the middle and late stages of the chlamydial developmental cycle, stages that include the formation of infectious elementary bodies. In the absence of detectable phosphorylation, ChxR formed homodimers
in vitro
and
in vivo
, similar to a phosphorylated OmpR/PhoB subfamily response regulator. ChxR was demonstrated to bind to its own promoter
in vivo
, supporting the role of ChxR as an autoactivator. Detailed analysis of the ChxR binding sites within its own promoter revealed a conserved
cis
-acting motif that includes a tandem repeat sequence. ChxR binds specifically to each of the individual sites and exhibits a relatively large spectrum of differential affinity. Taken together, these observations support the conclusion that ChxR, in the absence of phosphorylation, exhibits many of the characteristics of a phosphorylated (active) OmpR/PhoB subfamily response regulator.
Waiting for the Nuclear Renaissance: Exploring the Nexus of Expansion and Disposal in Europe
Authors: Darst Robert , Dawson Jane I.
Published: November 2010

This article focuses on the growing prospects for a nuclear power renaissance in Europe. While accepting the conventional wisdom that the incipient renaissance is being driven by climate change and energy security concerns, we argue that it would not be possible without the pioneering work of Sweden and Finland in providing a technological and sociopolitical solution to the industry's longstanding “Achilles' heel”: the safe, permanent, and locally acceptable disposal of high‐level radioactive waste. In this article, we track the long decline and sudden resurgence of nuclear power in Europe, examining the correlation between the fortunes of the industry and the emergence of the Swedish model for addressing the nuclear waste problem. Through an in‐depth exploration of the evolution of the siting model initiated in Sweden and adopted and successfully implemented in Finland, we emphasize the importance of transparency, trust, volunteerism, and “nuclear oases”: locations already host to substantial nuclear facilities. Climate change and concerns about energy independence and security have all opened the door for a revival of nuclear power in Europe and elsewhere, but we argue that without the solution to the nuclear waste quandary pioneered by Sweden and Finland, the industry would still be waiting for the nuclear renaissance.
Characterizations of Continuous and Discrete q-Ultraspherical Polynomials
Authors: Ismail Mourad E. H. , Obermaier Josef
Published: November 2010

We characterize the continuous q-ultraspherical polynomials in terms of the special form of the coefficients in the expansion DqPn(x) in the basis {Pn(x)}, Dq being the Askey-Wilson divided difference operator. The polynomials are assumed to be symmetric, and the connection coefficients are multiples of the reciprocal of the square of the L2 norm of the polynomials. A similar characterization is given for the discrete q-ultraspherical polynomials. A new proof of the evaluation of the connection coefficients for big q-Jacobi polynomials is given.
A method to calculate the multiphase flow properties of heterogeneous porous media by using network simulations
Authors: Tsakiroglou Christos D.
Published: November 2010

A method is suggested to compute the capillary pressure and relative permeability curves of heterogeneous porous media. The broad pore radius distribution (PRD) and throat radius distribution (TRD) are decomposed into relatively narrow component distribution functions which are used for the computer‐aided construction of pore‐and‐throat networks. The quasi‐static motion of menisci in pores and throats is tracked by accounting for capillary forces. The presence of fractal roughness along pore walls ensures the coexistence of both phases in pores. The calculation of the hydraulic conductance of each phase is based on the concept of constricted unit cell. Simulations in component pore networks constructed from narrow PRD and TRD produce a set of capillary pressure and relative permeability functions, the arithmetic averaging of which yields the corresponding functions for a heterogeneous synthetic pore network. This information is used by a dynamic simulator of drainage in permeability networks to predict experimental results of soil columns. © 2010 American Institute of Chemical Engineers AIChE J, 2011
Alterations in Wnt pathway activity in mouse serum and kidneys during lupus development
Authors: Tveita Anders Aune , Rekvig Ole Petter
Published: November 2010

Objective

The canonical Wnt/β‐catenin pathway was recently identified as a factor in the pathogenesis of several renal diseases. The aim of this study was to evaluate Wnt signaling activity during disease development in a murine model of lupus nephritis.

Methods

Wnt activity and Dkk‐1 expression were serially assayed in the serum and kidneys of (NZB × NZW)F1 mice during progression of lupus nephritis. The effects of serum obtained from mice with lupus and serum‐equivalent concentrations of Dkk‐1 on mesangial cells were assessed in vitro.

Results

Gene expression analyses revealed increased canonical Wnt pathway activity in kidneys during development of lupus nephritis, paralleled by an increase in renal and serum levels of the Wnt inhibitor Dkk‐1. Sera obtained from proteinuric‐stage (NZB × NZW)F1 mice showed strong Wnt‐inhibitory effects in vitro. Dkk‐1 concentrations comparable to those observed in lupus‐prone mice induced apoptosis in tubular and mesangial cells in vitro, whereas no such effect was seen for the range of concentrations observed in young prediseased mice and control BALB/c mice.

Conclusion

These data demonstrate that renal Wnt signaling activity is increased in lupus and is accompanied by an increase in renal and serum levels of Dkk‐1. The Wnt pathway is involved in the turnover of extracellular matrix constituents and represents a potential mediator of the morphologic changes that occur within the glomerulus during the development of nephritis. Furthermore, increased levels of Dkk‐1 serve as a potential proapoptotic stimulus in vitro and possibly in vivo and could be an important element in the initiation and progression of systemic and end‐organ disease manifestations in systemic lupus erythematosus.
Surgical outcome after incomplete endoscopic submucosal dissection of gastric cancer
Authors: Jung H , Bae J M , Choi M G , Noh J H , Sohn T S , Kim S
Published: November 2010

Background

Endoscopic resection of early gastric cancer is a relatively new and attractive treatment, but occasionally fails to remove all cancer lesions completely. This study aimed to elucidate clinicopathological factors that could be helpful in predicting residual tumour in the surgical specimen after incomplete endoscopic submucosal dissection (ESD).

Methods

Patients who underwent gastrectomy because of incomplete ESD between August 2004 and August 2008 were analysed. Clinicopathological characteristics were reviewed retrospectively from prospectively collected medical records. Patients were classified into groups with and without residual tumour. Pathology results following gastrectomy were compared with those of incomplete ESD.

Results

A total of 118 patients were included. The incidence of residual tumour in the surgical specimen was 24·6 per cent after incomplete ESD. Elevated/flat-type cancers, large tumours (at least 2 cm) and those limited to the mucosa had significantly higher incomplete ESD rates. Cancer limited to the mucosa and the presence of tumour in the lateral margin were associated with residual tumour in the surgical specimen (both P = 0·001).

Conclusion

Radical gastrectomy should be performed if pathological examination reveals a positive lateral resection margin after ESD.
Mechanistic Insights into the cis–trans Isomerization of Ruthenium Complexes Relevant to Catalysis of Olefin Metathesis
Authors: Poater Albert , Ragone Francesco , Correa Andrea , Szadkowska Anna , Barbasiewicz Michał , Grela Karol , Cavallo Luigi
Published: November 2010

The mechanism of the trans to cis isomerization in Ru complexes with a chelating alkylidene group has been investigated by using a combined theoretical and experimental approach. Static DFT calculations suggest that a concerted single‐step mechanism is slightly favored over a multistep mechanism, which would require dissociation of one of the ligands from the Ru center. This hypothesis is supported by analysis of the experimental kinetics of isomerization, as followed by 1H NMR spectroscopy. DFT molecular dynamics simulations revealed that the variation of geometrical parameters around the Ru center in the concerted mechanism is highly uncorrelated; the mechanism actually begins with the transformation of the square‐pyramidal trans isomer, with the RuCHR bond in the apical position, into a transition state that resembles a metastable square pyramidal complex with a Cl atom in the apical position. This high‐energy structure collapses into the cis isomer. Then, the influence of the N‐heterocyclic carbene ligand, the halogen, and the chelating alkylidene group on the relative stability of the cis and trans isomers, as well as on the energy barrier separating them, was investigated with static calculations. Finally, we investigated the interconversion between cis and trans isomers of the species involved in the catalytic cycle of olefin metathesis; we characterized an unprecedented square‐pyramidal metallacycle with the N‐heterocyclic carbene ligand in the apical position. Our analysis, which is relevant to the exchange of equatorial ligands in other square pyramidal complexes, presents evidence for a remarkable flexibility well beyond the simple cis–trans isomerization of these Ru complexes.
ChemInform Abstract: Humidity‐Sensitive Magnet Composed of a Cyano‐Bridged CoII—NbIV Dimetallic Assembly.
Authors: Imoto Kenta , Takahashi Daisuke , Tsunobuchi Yoshihide , Kosaka Wataru , Arai Michio , Tokoro Hiroko , Ohkoshi Shin‐ichi
Published: November 2010

Co2[Nb(CN)8]·8H2O is prepared by addition of an aqueous solution of K4[Nb(CN)8] to an aqueous solution of CoCl2.
ChemInform Abstract: The Phase Relationships in the Al—Zr—Ho Ternary System at 773 K.
Authors: Pang Mingjun , Zhan Yongzhong , Yang Wenchao , Li Chunliu , Du Yong
Published: November 2010

The phase relations of the title system at 773 K are determined over the whole composition range by powder XRD and DTA.
ChemInform Abstract: Selective Detection of Cs+ in Water Solutions via One‐Step Formation of a New Type of Struvite‐Like Phosphate.
Authors: Ferdov Stanislav , Lin Zhi
Published: November 2010

NaMnH(P0.9O4)2 is synthesized from an aqueous solution of NaH2PO4, MnSO4, and 2‐methyl‐1, 5‐pentanediamine (autoclave, 150 °C, 6 d).
ChemInform Abstract: Metal Salt Mediated Radical Reactions of 2‐Substituted‐1,4‐naphthoquinones.
Authors: Lin Zhen‐Yu , Chen Yu‐Ling , Lee Chih‐Shone , Chuang Che‐Ping
Published: November 2010

Silver‐catalyzed reaction of hydroxymethyl‐substituted naphthoquinones (I) with α‐oxocarboxylic acids (II) provides access towards naphtho‐fused furan derivatives (III).
ChemInform Abstract: One‐Pot Reductive Cleavage of exo‐Olefin to Methylene with a Mild Ozonolysis—Clemmensen Reduction Sequence.
Authors: Xu Shu , Toyama Takayuki , Nakamura Jun , Arimoto Hirokazu
Published: November 2010

Interestingly, the internal olefin (V) can be cleaved and reduced under similar conditions.
ChemInform Abstract: One‐Pot Reductive Amination of Carbonyl Compounds Using Sodium Borohydride‐Cellulose Sulfuric Acid.
Authors: Alinezhad Heshmatollah , Tollabian Zakieh
Published: November 2010

A novel protocol for the fast and efficient reductive amination of carbonyl compounds (25 examples) is developed that is comparable with various reducible functional groups such as NO2‐ and CN‐groups as well as C=C double bonds.
ChemInform Abstract: Commercial Zinc Oxide (Zn2+) as an Efficient and Environmentally Benign Catalyst for Homogeneous Benzoylation of Hydroxyl Functional Groups.
Authors: Tayebee Reza , Cheravi Fatemeh , Mirzaee Mehdi , Amini Mojtaba M.
Published: November 2010

A reaction pathway is proposed with zinc oxide serving as pre‐catalyst to form Zn2+ as the catalytically active species.
ChemInform Abstract: Unprecedented Copper(I)‐Catalyzed Photochemical Reaction of Diethyl Ether with Vicinal Diols and Ketals.
Authors: Mondal Sujit , Yadav Ram Naresh , Ghosh Subrata
Published: November 2010

1,2‐Diols and their ketals can be converted into the corresponding acetals via a novel process.
ChemInform Abstract: Synthesis and Reactions of Halo‐, Arylazo‐Substituted 3‐(3‐(1‐Naphthyl)acryloyl)tropolones. Formation of ((Naphthalen‐1‐yl)‐vinyl)substituted Heterocycle‐Fused Troponoid Compounds.
Authors: Gao Wentao , Sun Mingchun , Li Yang
Published: November 2010

The first synthesis and some electrophilic substitution and condensation reactions of naphthylacryloyltropolone (III) are described.
ChemInform Abstract: Enantioselective Catalytic α‐Alkylation of Aldehydes via an SN1 Pathway.
Authors: Brown Adam R. , Kuo Wen‐Hsin , Jacobsen Eric N.
Published: November 2010

Primary aminothiourea derivatives are shown to catalyze enantioselective alkylation of α‐branched aldehydes with diarylbromomethane.
ChemInform Abstract: Transition Metal Catalyzed Cross‐Couplings of Aryl Tosylates or Mesylates with Organoindium Reagents.
Authors: Zhang Liang , Luo Yong , Wu Jie
Published: November 2010

The title reactions give the corresponding coupling products in good yields.
ChemInform Abstract: Synthesis and Fluorescence Properties of α,α′‐Bis(substituted‐benzylidene)cycloalkanones Catalyzed by 1‐Methyl‐3(2‐(sulfooxy)ethyl)‐1H‐imidazol‐3‐ium Chloride.
Authors: Wan Yu , Chen Xiu‐Mei , Pang Li‐Ling , Ma Rui , Yue Cai‐Hui , Yuan Rui , Lin Wei , Yin Wei , Bo Rong‐Cheng , Wu Hui
Published: November 2010

Cyclohexanone derivatives have stronger fluorescence emission than cyclopropanone derivatives.
ChemInform Abstract: One‐Pot Synthesis of α‐Alkylidene‐γ‐butyrolacton‐2‐ones (Tetronic Acid Derivatives): Polar Solvent Induces a New Type of γ‐Lactonization.
Authors: Alizadeh Abdolali , Sabahnoo Hamideh , Noaparast Zohreh , Zohreh Nasrin , Mikaeili Azadeh
Published: November 2010

Stepwise reaction of alkyl acetoacetates such as (I) with primary amines and haloacetyl halides followed by thermal cyclization in a mixture of polar solvents offers an easy entry to E/Z‐mixtures of the title compounds, substructures of biologically active compounds.
ChemInform Abstract: Efficient Synthesis of Highly Functionalized 5‐Oxo‐4,5‐dihydro‐1H‐pyrroles and 5‐Oxo‐2,5‐dihydro‐1H‐pyrroles Derivatives.
Authors: Souldozi Ali , Dadrass Ali Reza , Ranjdost Zahra
Published: November 2010

Title compounds (III) and (V) are prepared via intramolecular Wittig‐reaction between dialkyl acetylenedicarboxylates and strong NH‐acids.
ChemInform Abstract: Synthesis of Chlorin‐Fused Monospirooxindolopyrrolidines Through a Facile [3 + 2]‐Cycloaddition of Azomethine Ylides.
Authors: Saravanan P. , Babu A. R. Suresh , Raghunathan R.
Published: November 2010

The title compounds (IV) are stable when exposed to air for 2—3 months.
ChemInform Abstract: Synthesis and Antimicrobial Activities of Some Novel 4‐Substituted Pyrazoline Derivatives.
Authors: Godhasra J. N. , Patel M. C. , Kansagara N. N. , Thanki B. P. , Shah V. R.
Published: November 2010

Some of the novel compounds (III) and (IV) possess significant antimicrobial activities.
ChemInform Abstract: Synthesis of Novel Halobenzyloxy and Alkoxy 1,2,4‐Triazoles and Evaluation for Their Antifungal and Antibacterial Activities.
Authors: Wan Kun , Zhou Cheng‐He
Published: November 2010

A variety of halobenzyloxy‐ and alkoxy‐1,2,4‐triazoles (VI) and their corresponding hydrochlorides is synthesized and screened for their antimicrobial activities.
ChemInform Abstract: Clay‐Catalyzed Synthesis of 5‐Substituent 1‐H‐Tetrazoles.
Authors: Chermahini Alireza Najafi , Teimouri Abbas , Momenbeik Fariborz , Zarei Amin , Dalirnasab Zeinab , Ghaedi Aseyeh , Roosta Mostafa
Published: November 2010

5‐Aryl‐1H‐tetrazoles (II) are obtained from aromatic nitriles and sodium azide in the presence of montmorillonite K‐10 or kaolin as catalyst.
ChemInform Abstract: Envirocat EPZ‐10: A Solid Acid Catalyst for the Synthesis of 1,8‐Dioxo‐octahydroxanthenes in Aqueous Medium.
Authors: Pore D. M. , Shaikh T. S. , Patil N. G. , Dongare S. B. , Desai U. V.
Published: November 2010

An ecofriendly method is used for the preparation of title compounds, e.g. (III).
ChemInform Abstract: Synthesis of Highly Functionalized Piperidines by One‐Pot Multicomponent Reaction Using Tetrabutylammonium Tribromide (TBATB).
Authors: Khan Abu T. , Lal Mohan , Khan Md. Musawwer
Published: November 2010

The process allows the synthesis of moderate to good yields of the target compounds, required as synthons for natural products and bioactive substances.The method fails if α‐naphthylamine is used.
ChemInform Abstract: Microwave‐Assisted Synthesis of 3‐Cyano‐2‐(1H‐indol‐3‐yl)pyridine Derivatives by a Multicomponent Reaction.
Authors: Geng Li‐Jun , Feng Guo‐Liang , Yu Jiu‐Gao
Published: November 2010

Advantages of the title procedure are experimental simplicity, easy work‐up and compatibility with various functional groups.
ChemInform Abstract: Two Novel Diterpenoids from Isodon rubescens var. lushanensis.
Authors: Pu Jian‐Xin , et al. et al.
Published: November 2010

Luanchunin A (I) and B (II) are isolated together with their precursor kamebakaurin (III).
ChemInform Abstract: Studies Toward Synthesis of Arteminolides: Intramolecular [5 + 2] Oxidopyrylium Ion Cycloaddition Reactions with Silicon Tether.
Authors: Sohn Jeong‐Hun
Published: November 2010

Compound (III), which has the common ring skeleton of the B‐ and B′‐rings of arteminolides, is synthesized in eight steps starting from 1,3‐propanediol via an unprecedented intramolecular [5 + 2] oxidopyrylium cycloaddition reaction with vinylsilyl ether tether as key step.
ChemInform Abstract: Synthesis of Novel Organogermanium Derivative (IV) Conjugated with Vitamin C and Study of Its Antioxidant Effects.
Authors: Lim Doo Hyeon , Li Minghua , Kim Eun‐hye , Ham Seung Wook
Published: November 2010

The title compound (IV) is found to display better antioxidant activity than ascorbic acid.
ChemInform Abstract: Cytotoxic Sesquilignans from the Roots of Saururus chinensis
Authors: Chin Young‐Won , Cai Xing‐Fu , Ahn Kyung‐Seop , Lee Hyeong‐Kyu , Oh Sei‐Ryang
Published: November 2010

structure elucidation and cytotoxicity of 7′′R,8′′S‐saucernol (I) and saucerneol J (7′′R,8′′S‐configuration) (II) along with six known compounds
ChemInform Abstract: Hygrobafilomycin, a Cytotoxic and Antifungal Macrolide Bearing a Unique Monoalkylmaleic Anhydride Moiety, from Streptomyces varsoviensis.
Authors: Ndejouong Basile Le S. Tchize , Sattler Isabel , Maier Armin , Kelter Gerhard , Menzel Klaus‐Dieter , Fiebig Heinz‐Herbert , Hertweck Christian
Published: November 2010

Hygrobafilomycin (I) shows strong antifungal, antiproliferative and cytotoxic activities.
ChemInform Abstract: Synthetic Routes and Plasmonic Properties of Noble Metal Nanoplates
Authors: Pastoriza‐Santos Isabel , Alvarez‐Puebla Ramon A. , Liz‐Marzan Luis M.
Published: November 2010

Review: 75 refs.
ChemInform Abstract: Tautomerism of the Metal Complexes with 1‐Amino‐4‐hydroxyanthaquinone
Authors: Fain V. Ya. , Zaitsev B. E. , Ryabov M. A.
Published: November 2010

Review: 25 refs.
ChemInform Abstract: Chemistry of the Cortistatins — A Novel Class of Antiangiogenic Agents.
Authors: Chen David Yu‐Kai , Tseng Chih‐Chung
Published: November 2010

Review: 66 refs.
ChemInform Abstract: A Novel Utilization of Acylsilanes in Organic Synthesis
Authors: Honda Mitsunori , Segi Masahito
Published: November 2010

Review: ca. 50 refs.
ChemInform Abstract: Catalytic Intramolecular Ketone Hydroacylation: Enantioselective Synthesis of Phthalides
Authors: Willis Michael C.
Published: November 2010

Review: 18 refs.
ChemInform Abstract: The Reach of Chemical Synthesis: Creation of a Mini‐Pipeline from an Academic Laboratory
Authors: Wilson Rebecca M. , Danishefsky Samuel J.
Published: November 2010

Review: about 100 refs.
ChemInform Abstract: COSMO—RS as a Tool for Property Prediction of IL Mixtures
Authors: Diedenhofen Michael , Klamt Andreas
Published: November 2010

Review: 58 refs.
ChemInform Abstract: Pyridyl‐amination as a Means of Analyzing Complex Sugar Chains
Authors: Hase Sumihiro
Published: November 2010

Review: 48 refs.
ChemInform Abstract: Nuclear Magnetic Resonance (NMR) Parameters of Transition Metal Complexes: Methods and Applications
Authors: Kaupp Martin , Buehl Michael
Published: November 2010

Review: 160 refs.
Quantitative dynamic‐memory analysis for Java
Authors: Garbervetsky Diego , Yovine Sergio , Braberman Víctor , Rouaux Martín , Taboada Alejandro
Published: November 2010

Space‐ and time‐predictability are hard to achieve for object‐oriented languages with automated dynamic‐memory management. Although there has been significant work to design APIs, such as the Real‐Time Specification for Java (RTSJ), and to implement garbage collectors to enable real‐time performance, quantitative space analysis is still in its infancy. This work presents the integration of a series of compile‐time analysis techniques to help predicting quantitative memory usage. In particular, we focus on providing tool assistance for identifying RTSJ scoped‐memory regions, their sizes, and overall memory usage. First, the tool‐suite synthesizes a memory organization where regions are associated with methods. Second, it infers their sizes inparametricclosed form in terms of relevant program variables. Third, it exhibits a parametric upper bound on the amount of available free memory required to execute a method. The experiments carried out with a RTSJ benchmark, a real‐time aircraft collision detector, show that semi‐automatic, tool‐assisted generation of scoped‐based code is both helpful and doable. Copyright © 2010 John Wiley & Sons, Ltd.
Ion permeation simulations by Gromacs—an example of high performance molecular dynamics
Authors: Krüger J. , Fels G.
Published: November 2010

The loss of inter‐neuron communication is related to many neuronal diseases such as Alzheimer's dementia. The nicotinic acetylcholine receptor (nAChR) plays a crucial role in this process and is severely affected upon disease progression. Successful therapy approaches rely on modulation of response signals, initiated by the flux of ions through the receptor integrated ion channel at the post‐synaptic membrane. We present here the comparison of two methods for calculating the energy barrier of nAChR mediated ion permeation, in terms of accuracy and performance. Detailed descriptions of archetypical Gromacs characteristics are given offering better insight into computational service providers to meet the needs of scientists. Copyright © 2010 John Wiley & Sons, Ltd.
Bayesian intelligent semantic mashup for tourism
Authors: Wang Wei , Zeng Guosun , Tang Daizhong
Published: November 2010

A common perception is that there are two competing visions for the future evolution of the Web: the Semantic Web and Web 2.0. In fact, Semantic Web technologies must integrate with Web 2.0 services for both to leverage each other's strengths. This paper illustrates how Semantic Web technologies can support information integration and make it easy to create semantic mashups. An intelligent recommendation system for tourism is presented to show the efficiency of our method. Through the ontology of tourism, the system allows the integration of heterogeneous online travel information. An integrated knowledge process is developed to guarantee the whole engineering procedure. Based on the Bayesian network technique, the system recommends tourist attractions to a user by taking into account the travel behavior both of the user and of other users. Copyright © 2010 John Wiley & Sons, Ltd.
An accurate power delivery system (PDS) design methodology for high‐speed digital systems
Authors: Nabil Shaymaa M. , El‐Rouby Alaa B. , Khalil Ahmed H.
Published: November 2010

The trend in high‐speed digital circuits is to increase speed and density and to operate at lower voltage. This fast increase in the switching speed combined with the decrease of the operating voltage causes the allowable absolute voltage variations to decrease, which makes the PDS design a more challenging task than ever.

Moreover, the complex 3D nature of the modern PDS causes it to be more sensitive to capacitors' placement as well as capacitance value.

In this paper, we introduce an efficient complete solution for the design of high‐speed digital PDS. This solution (a) takes the effects of the decoupling capacitor placement into consideration through a 3D electromagnetic simulation of the PDS, (b) defines a more‐realistic PDS design target, and (c) presents a clear capacitor value selection methodology. Finally, we applied our methodology to an industrial test case, compared its results with that of industrial design, and showed its advantages. Copyright © 2010 John Wiley & Sons, Ltd.
Metformin and atorvastatin combination further protect the liver in type 2 diabetes with hyperlipidaemia
Authors: Matafome P. , Louro T. , Rodrigues L. , Crisóstomo J. , Nunes E. , Amaral C. , Monteiro P. , Cipriano A. , Seiça R.
Published: November 2010

Background

Non‐alcoholic fatty liver disease (NAFLD) and type 2 diabetes are associated with dyslipidaemia, inflammation and oxidative stress. However, the pathophysiology of NAFLD in type 2 diabetes with hyperlipidaemia is not fully known, as well as the utility of the commonly prescribed anti‐diabetic and lipid‐lowering drugs in ameliorating liver injury markers.

Methods

Hepatic complications of type 2 diabetes with hyperlipidaemia and the effects of atorvastatin and metformin, isolated and in association, in systemic and hepatic inflammatory and oxidative stress markers were tested using genetic type 2 diabetic Goto–Kakizaki rats fed with a high‐fat diet.

Results

The high‐fat diet aggravated the overall metabolic state and the hepatic markers of injury. All treatments decreased fasting glycaemia, insulin resistance and free fatty acid levels. Combined treatment further decreased C‐reactive protein (CRP), adiponectin, liver tumour necrosis factor‐α (TNF‐α) and interleukin‐6 (IL‐6), systemic and hepatic oxidative stress and portal inflammation.

Conclusions

Our data provides evidence of a greater benefit with a combination of atorvastatin and metformin in improving liver injury in type 2 diabetes with hyperlipidaemia. Copyright © 2010 John Wiley & Sons, Ltd.
Advanced motion as a hybrid system
Authors: Suzuki Tatsuya
Published: November 2010

This paper presents a modeling and analysis strategy for advanced complex human motion based on a hybrid system framework. The motion modeling problem is addressed as a parameter estimation problem under the piecewise ARX model, which is a class of hybrid dynamical system. The advantages of motion modeling based on hybrid dynamics are: (1) complex dynamical behavior can be represented in terms of dynamical primitives together with the mechanism of switching between them; (2) the resulting model may be useful for various applications, such as the design of assist controllers, recognition of human behavior, and so on. Finally, the newly developed strategy is applied to a driver's vehicle following task and a peg‐in‐hole task, which represent two typical classes of complex human motion. The results obtained show the usefulness of hybrid dynamics for representing complex human motion. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(12): 35–43, 2010; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.10236
A study of spectral correction for self‐absorption of radiation unit in integrating sphere spectral photometer
Authors: Mishima Syunsuke , Oshima Kosei
Published: November 2010

Integrating sphere spectral photometers are used to measure the spectral distribution, to calculate the total luminous flux, and to calculate the chromaticity coordinates of LEDs. When measuring the light source emission in an integrating sphere it is necessary to take account of self‐absorption. LEDs with colored parts, such as printed circuit boards, heat sinks, etc., require special attention. In case of a large enough sphere, the self‐absorption spectrum of an LED has a nearly flat spectral distribution and a low absorption level. Hence, the calculated total luminous flux and chromaticity coordinates of the LED are almost the same regardless of whether the self‐absorption correction is applied or not. In the case of a small integrating sphere, the spectral distribution of LED self‐absorption is slightly affected by spectrum correction samples. The correction spectrum can be measured individually for each color piece with an auxiliary lamp set up in the integrating sphere. After spectral correction, the values of the total luminous flux and chromaticity coordinates measured in a small integrating sphere closely match the results obtained in the large sphere. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(12): 10–16, 2010; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.10293
Regulatory T cells exhibit enhanced migratory characteristics, a feature impaired in patients with multiple sclerosis
Authors: Schneider‐Hohendorf Tilman , Stenner Max‐Philipp , Weidenfeller Christian , Zozulya Alla L. , Simon Ole J. , Schwab Nicholas , Wiendl Heinz
Published: November 2010

Migration of immune cells characterizes inflammation and plays a key role in autoimmune diseases such as MS. CD4+Foxp3+ regulatory T cells (Treg) have the potential to dampen immune responses but show functional impairment in patients with MS. We here show that murine Treg exhibit higher constitutive cell motility in horizontal migration on laminin, surpass non‐Treg in transwell assays through microporous membranes as well as across primary brain endothelium and are present in the naïve CNS to a significantly higher extent compared to spleen, lymph nodes and blood. Likewise, human Treg from healthy donors significantly exceed non‐Treg in migratory rates across primary human brain endothelium. Finally, we investigated whether the propensity to migrate is impaired as a feature of autoimmunity and therefore tested patients with MS. Treg from patients with stable relapsing‐remitting MS show significantly impaired migratory capacity under non‐inflammatory conditions compared to healthy donors. We hypothesize that the enhanced propensity to migrate is a feature of Treg that allows for an equilibrium in parenchymal immune surveillance, e.g. of the CNS. Impaired Treg migration across the intact blood–brain barrier, as observed for Treg from patients with MS, indicates a broader functional deficiency hypothetically contributing to early CNS lesion development or phases of MS remissions.
Chemical synthesis of phytosterol esters of polyunsaturated fatty acids with ideal oxidative stability
Authors: Qianchun Deng , Pin Zhang , Qingde Huang , Fenghong Huang , Fang Wei , Mingming Zheng , Xiao Yu , Qi Zhou , Chang Zheng
Published: November 2010

In this study, direct esterification of phytosterols with polyunsaturated fatty acid (PUFA) catalyzed by sodium bisulfate to produce sterol esters of PUFA was performed without organic solvent. Considering on both degree of esterification (DE) and oxidative stability, response surface methodology (RSM) was employed for modeling the phytosterol esters of PUFA production to obtain a food grade process. The optimal and mild reaction conditions were obtained as follows: mass ratio of PUFA:phytosterols = 4:1; amount of catalyst: 3% of the raw materials weight; reaction temperature 130°C; reaction time 8 h. Under these conditions, the degree of esterification was up to 96%, GC, TLC, NMR and GC‐MS results showed that purity of purified sterol ester was above 99%, and β‐sitosterol linolenate account for about 88%. Sterol ester of PUFA possessed low peroxide value (PV) (0.96 meq/kg) and conjugated diene (CD) value (2.15 mmol/kg), and high oxidative induction period (OIP) (10.4 h). Addition amount of sterol ester of PUFA into soybean oil, rapeseed oil, and flaxseed oil below 1, 1, and 3%, respectively, could increase OIP of the vegetable oil. The primrose phytosterol esters of PUFA possessed very low melting point, crystallization temperature, and greater solubility in oils. All the characteristics favored the wide application of sterol ester of PUFA produced by the food grade process in different formulations of functional foods.
A Simple and Effective Method for α‐Hydroxylation of β‐Dicarbonyl Compounds Using Oxone as an Oxidant without a Catalyst
Authors: Yu Jun , Cui Jian , Zhang Chi
Published: November 2010

Oxone has been found to be a highly efficient reagent for the introduction of a hydroxy group at the α position of a variety of β‐dicarbonyl compounds in the homogeneous solvent mixture of water and 1,4‐dioxane at 60 °C.
Nanoporous Gold Leaf for Amperometric Determination of Nitrite
Authors: Ge Xingbo , Wang Liqin , Liu Zhaona , Ding Yi
Published: November 2010

Ultra‐thin free‐standing nanoporous gold leaf made by dealloying exhibits excellent electrocatalytic activities toward nitrite oxidation. The electrochemical responses of nitrite ions on this novel nano‐electrode is found not dependent on pH over a wide range from 4.5 to 8.0, which is markedly different from that of gold oxidation, a process known to be highly pH‐sensitive. Amperometric study shows a linear relationship for nitrite determination in a concentration range from 1 µM to 1 mM. This nanostructured gold electrode displays good stability, repeatability and selectivity which suggests its potential for the development of new electrochemical sensors.
Electrochemical Study of Gliclazide and Its Complexation with β‐Cyclodextrin
Authors: Radi Abd‐Elgawad , Eissa Shimaa
Published: November 2010

The electrochemical oxidation of gliclazide has been investigated at glassy carbon electrode in phosphate buffer solutions over the pH range 2.7–11.8 using cyclic and differential pulse voltammetry (DPV). Gliclazide exhibited one anodic peak in the pH range of 2.7–6.3 and a second peak was produced above pH 6.3. The oxidation processes have been shown to be irreversible and diffusion controlled. The formation of an inclusion complex of gliclazide with β‐cyclodextrin (β‐CD) has been investigated by cyclic and differential pulse voltammetry. A phase solubility study with spectrophotometric detection has been also applied. The stability constant of the complex was determined to be 839 and 360 M−1 using the differential pulse voltammetric method and the phase solubility method, respectively.