bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and implement a virtual learning architecture for troubleshooting practice of automotive chassis
Authors: Liang Janus S.
Published: February 2009

In this research, a web‐based troubleshooting architecture of automobile chassis is constructed, and it can support distance learning of practical courses in automotive chassis repair and maintenance. This system allows remote learners to operate a practical training module for troubleshooting through the Internet. There are several subjects discussed in this research: (1) developing the learning contents for repairing automotive chassis; (2) building the virtual and interactive platform for browsing and practice of troubleshooting; (3) creating the online evaluation tools and effectiveness analysis. The framework has been tested and implemented in the course, “Automotive Practice: Chassis,” in the Department of Mechanical Engineering at Yung‐Ta Institute of Technology and Commerce during the spring semester of 2005. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 18: 512–525, 2010; View this article online atwileyonlinelibrary.com; DOI 10.1002/cae.20219
Downer‐to‐Riser Coupling Technique for Petroleum Refining
Authors: Wu C. , Cheng Y. , Jin Y.
Published: February 2009

Many recent developments in the fluid catalytic cracking (FCC) technique have focused on achieving cleaner gasoline with less olefins and maximizing light olefins such as propylene. A coupled high‐density downer‐to‐riser reactor was proposed to utilize the advantages of both downer and riser to improve the gasoline quality and to efficiently control the product distribution. The basic idea is to decompose the complex FCC reactions into two reaction zones with distinct operating conditions. The downer accommodates high‐severity operation at the initial stage with the benefit of near plug‐flow while the riser is operated at a lower temperature with longer contacting time to promote hydrogen shift reactions. A comprehensive 2D reactor model is presented to predict the reactor performances for different reactor designs. The coupled downer‐to‐riser reactor design was found to have more light olefins and cleaner gasoline than the conventional riser and the coupled riser‐to‐riser reactor design.
A Novel Liquid‐Solid Circulating Fluidized‐Bed Bioreactor for Biological Nutrient Removal from Municipal Wastewater
Authors: Chowdhury N. , Zhu J. , Nakhla G. , Patel A. , Islam M.
Published: February 2009

Biological nutrient removal (BNR) using a novel liquid‐solid circulating fluidized‐bed (LSCFB) bioreactor was assessed with and without particle recirculation. The LSCFB employs attached microbial films for the biodegradation of both organics and nutrients within a single circulating fluidized‐bed unit. This new technology combines the more compact and efficient fixed‐film process with the BNR process that provides the additional removal of nitrogen and phosphorous. A lab‐scale LSCFB was demonstrated to treat degritted municipal wastewater (MWW), operated at an empty‐bed contact time of 0.82 h. The system removed 94, 80 and 65 % of organic (chemical oxygen demand, COD), nitrogen (N), and phosphorous (P), respectively, without particle recirculation, whereas with particle recirculation the system removed excess phosphorus and achieved overall removal efficiencies of 91, 78 and 85 % for C, N, and P, respectively. The system generated effluent characterized by <5 mg biological oxygen demand/L, <5 mg total suspended solids/L, <1 mg NH4‐N/L, <7 mg total nitrogen/L, and <1 mg PO4‐P/L. Combination of nitrification, denitrification and enhanced biological phosphorus removal in one unit saves space, reduces energy consumption, and also produces less sludge at approximately 0.12–0.13 g volatile suspended solids/g COD consumed. Excellent lab‐scale results led to the establishment of a pilot‐scale LSCFB for MWW treatment at a capacity of 5000 L/day. Initial results of the pilot‐study showed a similar trend in BNR as observed in the lab‐study.
Making sense of CSR communication
Authors: Ziek Paul
Published: February 2009

Although a great deal of research has focused on communicating Corporate Social Responsibility (CSR), the literature is diverse and encompasses a plethora of theories and approaches. It is still unclear what communicative behaviors carry the messages of organizational virtuosity and the implementation of responsible initiatives. What is missing is a simple, inclusive assessment of how organizations explicitly communicate the behaviors that constitute CSR. Accordingly, the purpose of this paper is to provide an illustration of the accounts that constitute CSR communication. Fifty US firms are examined for CSR moves within a variety of organizational contexts. The results show that communicating CSR is limited to large organizations and primarily, that they communicate CSR by conveying information about classically accepted responsible and virtuous behaviors. This patterned communicative behavior is a process that organizations engage in to make sense of CSR. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Stakeholder engagement and corporate social responsibility reporting: the ownership structure effect
Authors: Prado‐Lorenzo Jose‐Manuel , Gallego‐Alvarez Isabel , Garcia‐Sanchez Isabel M.
Published: February 2009

Social disclosure, according to Ullmann's conceptual framework (1985), could be explained by stakeholder power, strategic posture and economic performance, where the power of stakeholders is a function of the resources they control that are essential to the company.

The aim of this work is to test the effect that shareholder power and dispersed ownership structure have on the decision to disclose corporate social responsibility (CSR) information in the Spanish context, controlling for the rest of the dimensions.

Our results allow us to affirm that this paper tests a stakeholder theory approach to analyzing corporate social disclosures and is consistent with the framework proposed, although the power of shareholders is quite limited. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Monitoring and numerical modelling of riverbank erosion processes: a case study along the Cecina River (central Italy)
Authors: Luppi Laura , Rinaldi Massimo , Teruggi Liliana B. , Darby Stephen E. , Nardi Laura
Published: February 2009

Riverbank retreat along a bend of the Cecina River, Tuscany (central Italy) was monitored across a near annual cycle (autumn 2003 to summer 2004) with the aim of better understanding the factors influencing bank changes and processes at a seasonal scale. Seven flow events occurred during the period of investigation, with the largest having an estimated return period of about 1·5 years. Bank simulations were performed by linking hydrodynamic, fluvial erosion, groundwater flow and bank stability models, for the seven flow events, which are representative of the typical range of hydrographs that normally occur during an annual cycle. The simulations allowed identification of (i) the time of onset and cessation of mass failure and fluvial erosion episodes, (ii) the contributions to total bank retreat made by specific fluvial erosion and mass‐wasting processes, and (iii) the causes of retreat. The results show that the occurrence of bank erosion processes (fluvial erosion, slide failure, cantilever failure) and their relative dominance differ significantly for each event, depending on seasonal hydrological conditions and initial bank geometry. Due to the specific planimetric configuration of the study bend, which steers the core of high velocity fluid away from the bank at higher flow discharges, fluvial erosion tends to occur during particular phases of the hydrograph. As a result fluvial erosion is ineffective at higher peak discharges, and depends more on the duration of more moderate discharges. Slide failures appear to be closely related to the magnitude of peak river stages, typically occurring in close proximity to the peak phase (preferentially during the falling limb, but in some cases even before the peak), while cantilever failures more typically occur in the late phase of the flow hydrograph, when they may be induced by the cumulative effects of any fluvial erosion. Copyright © 2008 John Wiley & Sons, Ltd.
The effect of CeO2 on Pt/CeO2/CNT catalyst for CO electrooxidation
Authors: Yuan H. , Guo D. , Li X. , Yuan L. , Zhu W. , Chen L. , Qiu X.
Published: February 2009

Pt/CeO2/CNT catalysts were prepared by adsorbing Pt nanoparticles on the supports of CNTs coated with CeO2. The electrocatalytic performances in respect to the electrooxidation of chemisorbed CO were tested using potential step and stripping voltammetry methods under variable sweep rate and temperature conditions. At 10 mV s–1, the CO stripping voltammogram exhibited the peak splitting phenomenon. The oxidation charge and the peak potential of the two voltammetric peaks changed regularly with the number of Pt and CeO2 neighbours, the sweep rate, and the temperature. We considered that the low potential peak originated from the reaction of COads with hydroxyl groups on CeO2 adjacent to Pt sites, while the high potential peak came from the reaction of COads with hydroxyl groups produced on pure Pt. Furthermore, the experimental results of the peak potential against the logarithm of the sweep rate and the logarithm of the current maximum time against the step potential were plotted and intersecting lines with different slopes in high and low potential regions in the plot were observed. The lines intersected at lower potentials on the Pt/CeO2/CNT electrode than on the Pt/CNT electrode, which was attributed to the contribution of hydroxyl groups on CeO2.
Bone marrow‐derived cells in the central nervous system of a mouse model of amyotrophic lateral sclerosis are associated with blood vessels and express CX3CR1
Authors: Lewis Coral‐Ann B. , Solomon Jennifer N. , Rossi Fabio M. , Krieger Charles
Published: February 2009

Amyotrophic lateral sclerosis (ALS) is associated with increased numbers of microglia within the CNS. However, it is unclear to what extent bone marrow (BM)‐derived cells contribute to this microgliosis. We have studied the adoptive transfer of green fluorescent protein (GFP)‐labeled whole BM cells and BM from mice that express GFP only in CX3CR1+ cells (CX3CR1+/GFP) into the CNS of a murine model of ALS having over‐expression of mutant superoxide dismutase (mSOD), and wt littermates. We find that most GFP+ and CX3CR1+/GFP cells are found adjacent to the microvasculature within the CNS, both in mSOD and wt mice. GFP+ and CX3CR1+/GFP cells within the CNS have a variety of morphologies, including cells with an elongated appearance, weak Iba‐1 immunoreactivity, and often mannose receptor immunoreactivity, indicating that these cells are perivascular microglia. Typically, less than 10% of BM‐derived cells had a stellate‐shape and expressed strong Iba‐1 immunoreactivity, as expected for parenchymal microglia, indicating that BM‐derived cells uncommonly generate parenchymal microglia. Adoptive transfer of BM‐derived cells from CX3CR1+/GFP mice revealed that many elongated cells are GFP+, demonstrating that some perivascular cells are derived from BM cells of the CX3CR1+ lineage. The significantly greater numbers of BM cells in mSOD than in control mice indicate that the presence of these BM cells in the spinal cord is regulated by conditioning stimuli that may include irradiation and inflammatory factors within the CNS. © 2009 Wiley‐Liss, Inc.
Comparative screening of glial cell types reveals extracellular matrix that inhibits retinal axon growth in a chondroitinase ABC‐resistant fashion
Authors: Siddiqui Sonia , Horvat‐Broecker Andrea , Faissner Andreas
Published: February 2009

Glial cells provide an optimal surface for attachment, migration, and growth of CNS neurons. This study was designed to investigate the ability of four glia cell types, retinal Müller Glia (MG), cortical astrocytes (CA), A7, and Oli‐neu to support the outgrowth of embryonic day 18 rat retinal explants. Extracellular matrix (ECM) prepared by water lysis of monolayers of A7, CA, and MG cells significantly increased, whereas Oli‐neu‐derived ECM inhibited fiber growth. Analogous results were obtained with explants on live monolayers. The inhibitory effect of Oli‐neu matrix, but not of live cells, could be neutralized with the Rho‐kinase inhibitor Y27632. Studies on the message and protein level revealed the expression of a range of ECM glycoproteins and the major chondroitin sulfate proteoglycans (CSPGs). Oli‐neu produced large amounts of tenascin‐C (TN‐C), DSD‐1‐PG/phosphacan, and NG2, correlating with its inhibitory properties. Upon treatment with chondroitinase ABC (ChABC), retinal axon growth was increased on CA, MG, and A7, in accordance with the degradation of inhibitory CSPGs. In contrast, inhibition exerted by Oli‐neu or postnatal oligodendrocytes was not abolished. When the neurite growth promoting properties of TN‐C were neutralized by the monoclonal antibody J1/tn2, retinal axon growth was clearly diminished on MG, indicating a dominance of the FNIII domain D of TN‐C in this cell type. The results suggest that glial cells construct complex ECM structures with distinct properties ranging from promotion to inhibition of retinal axons, depending on their composition. Furthermore, inhibitory ECM may resist ChABC treatment in some situations. © 2009 Wiley‐Liss, Inc.
Low folate transport across intestinal basolateral surface is associated with down‐regulation of reduced folate carrier in in vivo model of folate malabsorption
Authors: Hamid Abid , Kiran Manjula , Rana Satyavati , Kaur Jyotdeep
Published: February 2009

The process of folate transport regulation across biological membranes is of considerable interest because of its ultimate role in providing one‐carbon moieties for key cellular metabolic reactions and exogenous requirement of the vitamin in mammals. Although, intestinal folate malabsorption is established phenomena in alcoholism; however, there is no knowledge regarding the mechanism of folate exit across intestinal basolateral membrane (BLM) to circulation during alcohol associated malabsorption. In the present study, male Wistar rats were fed 1 g/kg body weight/day ethanol (20% solution) orally for 3 months and regulatory characteristics of folate transport at BLM surface were evaluated. The folate transport was found to be carrier mediated, saturable, with pH optima at 7.0, besides exhibiting Na+ independence. The chronic alcohol ingestion resulted in alteration of transport kinetics, shifting the process to K+ dependent one besides affecting the status of SS linkage of the transport system. Importantly, chronic ethanol ingestion reduced the folate exit across the BLM by decreasing the affinity of transporter (high Km) for substrate and by decreasing the number of transporter molecules (low Vmax) on the surface. The decreased basolateral transport activity was associated with down‐regulation of the reduced folate carrier (RFC) which resulted in decreased RFC protein levels in BLM in rat model of alcoholism. The study suggests that during alcohol ingestion, RFC mediated deregulated folate transport across BLM also attributes to folate malabsorption. © 2009 IUBMB IUBMB Life, 61(3): 236–243, 2009
RNase P RNA‐mediated cleavage
Authors: Kirsebom Leif A. , Trobro Stefan
Published: February 2009

Metal(II)‐induced hydrolysis of RNA produce products with 5′‐hydroxyls and 2′;3′‐cyclic phosphates at the ends. Ribozymes are RNA molecules that act as catalysts. Some ribozymes that cleave RNA also generate 5′‐hydroxyls and 2′;3′‐cyclic phosphates whereas others produces 5′‐phosphates and 3′‐hydroxyls at the ends of the cleavage products. RNase P is an essential endoribonuclease involved in RNA processing. The catalytic RNA subunit of RNase P is a trans‐acting ribozyme that cleaves various RNA substrates in vitro generating 5′‐phosphates and 3′‐hydroxyls as cleavage products. The activity depends on the presence of metal(II) ions such as Mg2+. RNase P RNA has therefore to facilitate a nucleophilic attack that generates the correct product ends and prevent metal(II)‐induced hydrolysis of the RNA substrate. In this review, we will discuss our current understanding of the interactions between RNase P RNA and its substrate, role of specific residues with respect to catalysis and positioning of functionally important Mg2+ at and in the vicinity of the cleavage site that ensures that products with correct ends are generated. Moreover, we will discuss the composition of RNase P and its RNA subunit in an evolutionary perspective. © 2009 IUBMB IUBMB Life, 61(3):189–200, 2009
Computational analysis of the cathepsin B inhibitors activities through LR‐MMPBSA binding affinity calculation based on docked complex
Authors: Zhou Zhigang , Wang Yanli , Bryant Stephen H.
Published: February 2009

Cathepsin B, a ubiquitous lysosomal cysteine protease, is involved in many biological processes related to several human diseases. Inhibitors targeting the enzyme have been investigated as possible diseases treatments. A set of 37 compounds were recently found active in a high throughput screening assay to inhibit the catalytic activity of Cathepsin B, with chemical structures and biological test results available to the public in the PubChem BioAssay Database (AID 820). In this study, we compare these experimental activities to the results of theoretical predictions from binding affinity calculation with a LR‐MM‐PNSA approach based on docked complexes. Strong correlations (r2 = 0.919 and q2 = 0.887 for the best) are observed between the theoretical predictions and experimental biological activity. The models are cross‐validated by four independent predictive experiments with randomly split compounds into training and test sets. Our results also show that the results based on protein dimer show better correlations with experimental activity when compared to results based on monomer in the in silico calculations. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009
Exploring the parameter space of the coarse‐grained UNRES force field by random search: Selecting a transferable medium‐resolution force field
Authors: He Yi , Xiao Yi , Liwo Adam , Scheraga Harold A.
Published: February 2009

We explored the energy‐parameter space of our coarse‐grained UNRES force field for large‐scaleab initiosimulations of protein folding, to obtain good initial approximations for hierarchical optimization of the force field with new virtual‐bond‐angle bending and side‐chain‐rotamer potentials which we recently introduced to replace the statistical potentials. 100 sets of energy‐term weights were generated randomly, and good sets were selected by carrying out replica‐exchange molecular dynamics simulations of two peptides with a minimal α‐helical and a minimal β‐hairpin fold, respectively: the tryptophan cage (PDB code: 1L2Y) and tryptophan zipper (PDB code: 1LE1). Eight sets of parameters produced native‐like structures of these two peptides. These eight sets were tested on two larger proteins: the engrailed homeodomain (PDB code: 1ENH) and FBP WW domain (PDB code: 1E0L); two sets were found to produce native‐like conformations of these proteins. These two sets were tested further on a larger set of nine proteins with α or α + β structure and found to locate native‐like structures of most of them. These results demonstrate that, in addition to finding reasonable initial starting points for optimization, an extensive search of parameter space is a powerful method to produce a transferable force field. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009
Gibbs energy of activation for thermal isomerization of (1Z)‐acetaldehyde hydrazone and (1Z)‐acetaldehyde N,N‐dimethylhydrazone by Gaussian‐4 theory and CCSD(T)/CBS computations
Authors: Lu Shih‐I
Published: February 2009

In this article, we examined the Gibbs energy of activation for the Z/E thermal isomerization reaction of (1Z)‐acetaldehyde hydrazone and (1Z)‐acetaldehyde N,N‐dimethylhydrazone, at 298.15 K in the solvent of cyclohexane. We carried out computations employing both the Gaussian‐4 (G4) theory and the coupled cluster method using both single and double substitutions and triple excitations noniteratively, CCSD(T). The CCSD(T) energy is extrapolated to the complete basis set (CBS). We compared the calculated results to the available experimental observation. It appeared that both G4 and CCSD(T)/CBS computations overestimated the experimental value by as much as about 6 and 12 kcal/mol in the present two cases. We discussed possible sources of error and proposed the experimental kinetic data could be questionable. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009
Molecular dynamics simulation exploration of cooperative migration mechanism of calcium ions in sarcoplasmic reticulum Ca2+‐ATPase
Authors: Huang Yongqi , Li Huifang , Bu Yuxiang
Published: February 2009

Calcium ATPase is a member of the P‐type ATPase, and it pumps calcium ions from the cytoplasm into the reticulum against a concentration gradient. Several X‐ray structures of different conformations have been solved in recent years, providing basis for elucidating the active transport mechanism of Ca2+ ions. In this work, molecular dynamics (MD) simulations were performed at atomic level to investigate the dynamical process of calcium ions moving from the outer mouth of the protein to their binding sites. Five initial locations of Ca2+ ions were considered, and the simulations lasted for 2 or 6 ns, respectively. Specific pathways leading to the binding sites and large structural rearrangements around binding sites caused by uptake of calcium ions were identified. A cooperative binding mechanism was observed from our simulation. Firstly, the first Ca2+ ion binds to site I, and then, the second Ca2+ ion approaches. The interactions between the second Ca2+ and the residues around site I disturb the binding state of site I and weaken its binding ability for the first bound Ca2+. Because of the electrostatic repulsion of the second Ca2+ and the electrostatic attraction of site II, the first bound Ca2+ shifts from site I to site II. Concertedly, the second Ca2+ binds to site I, forming a binding state with two Ca2+ ions, one at site I and the other at site II. Both of Glu908 and Asp800 coordinate with the two Ca2+ ions simultaneously during the concerted binding process, which is believed to be the hinge to achieve the concerted binding. In our simulations, four amino acid residues that serve as the channel to link the outer mouth and the binding sites during the binding process were recognized, namely Tyr837, Tyr763, Asn911, and Ser767. The analyses regarding the activity of the proteins via mutations of some key residues also supported our cooperative mechanism. © 2009 Wiley Periodicals, Inc. J Comput Chem 2009
Fusions of pyrido[4′,3′:4,5]thieno[2,3‐d]pyrimidines withN‐heterocyclic moieties
Authors: Ahmed E. Kh. , Sensfuss U. , Habicher W. D.
Published: February 2009

Versatile 2‐thioxopyrimidine‐type building blocks ethyl 3‐(2‐ethoxy‐2‐oxoethyl)‐4‐oxo‐2‐thioxo‐1,2,3,4,5,6,7,8‐octahydropyrido[4′,3′:4,5]thieno[2,3‐d]pyrimidine‐7‐carboxylate (4) and ethyl 4‐oxo‐2‐thioxo‐1,2,3,4,5,6,7,8‐octahydropyrido[4′,3′:4,5]thieno[2,3‐d]pyrimidine‐7‐carboxylate (8) were synthesized from diethyl 2‐amino‐4,5,6,7‐tetrahydrothieno[2,3‐c]pyridine‐3,6‐dicarboxylate (1). Derivatives of linear and angular heterocyclic systems having the imidazole and 1,2,4‐triazole ring were obtained from the key intermediates4and8, respectively.
Synthesis of some 3,6‐disubstituted pyridazines
Authors: Shin Mi‐Seon , Kang Young‐Jin , Chung Hyun‐A , Park Jung‐Won , Kweon Deok‐Heon , Lee Woo Song , Yoon Yong‐Jin , Kim Sung‐Kyu
Published: February 2009

Some novel 3‐halo‐6‐(4‐substituted‐phenoxy)pyridazines and 3,6‐di‐(4‐substituted‐phenoxy)pyridazines were synthesized from 3,6‐dichloropyridazine or 3,6‐diiodopyridazine. 3,6‐Diiodopyridazine was prepared from 3,6‐dichloropyridazine using hydriodic acid/iodine monochloride.
Synthesis of 3,4‐diaminopyridine and imidazo[4,5‐c]pyridines by nitration of 4‐acylaminopyridines
Authors: Bakke J. M. , Riha J.
Published: February 2009

New methods for the preparation of 3,4‐diaminopyridine (5) and imidazo[4,5‐c]pyridines 7a,7b based on direct nitration of 4‐acylaminopyridines 3a, 3b have been explored.
Attempts to prepare some 3‐substituted azolo[1,2‐x]azines, intermediates in the synthesis of azaaplysinopsin derivatives
Authors: Jukić Lucija , Čopar Anton , Stanovnik Branko , Svete Jurij , Malešič Mateja , Krbavčič Aleš
Published: February 2009

Some 3‐substituted pyrrolo[1,2‐a]azines 4a‐d were prepared in low yields from the corresponding 2‐methylpyridines 1a,b and pyrazine derivatives 1c,d by quaternization with methyl bromoacetate followed by treatment with N,N‐dimethylformamide dimethyl acetal. Ethyl 2‐pyridinylacetate (5) and 2‐pyridinylaceto‐nitrile (6) were converted with 4‐(2‐bromo‐1‐dimethylaminoethylidene)‐2‐phenyl‐5(4H)‐oxazolone (9) into pyrrolo[1,2‐a]pyridine derivatives 10 and 12, intermediates in the synthesis of azaaplysinopsins.
Synthesis of 4,5‐disubstituted benzo[c][2,7]naphthyridines as precursors of pyrido[2,3,4‐kl]acridones and related natural products
Authors: Guillier F. , Nivoliers F. , Godard A. , Marsais F. , Quéguiner G.
Published: February 2009

A methodical investigation on functionalization by carbonylated groups in position 4 and 5 of the benzo[c][2,7]naphthyridine skeleton has been undertaken. In particular the study has shown the complex influence of these two sites on each other. A careful choice of both substituents in 4 and 5 permitted the synthesis of an interesting pyrido[2,3,4‐kl]acridone tetracyclic structure through an intramolecular Mukayama aldolisation reaction. The structure is supposed to be a potential precursor to various marine alkaloids of the pyridoacridine family.
Synthesis ofbis‐3‐alkyl‐5‐arylhydantoins andbis‐3‐alkyl‐5‐arylthiohydantoins separated by two and four carbon atoms
Authors: Salerni O. Leroy , Van Tyle W. Kent , Mustra David J. , Emerich Kevin S. , Fuerst Douglas E. , Zia‐Ebrahimi M.
Published: February 2009

Synthesis of 1,2‐ and 1,4‐bis‐thiohydantoins and hydantoins employing ethylenediamine and 1,4‐diaminobutane as spacers is described. Compounds containing a two carbon bridge were synthesized by alkylation of ethylenediamine with two equivalents of N‐t‐butyl‐α‐(p‐toluenesulfonyloxy)phenylacetamide3. The phenyl isothiocyanate adduct of 3 cyclized in refluxing toluene to form1a. Other isothiocyanate or isocyanate adducts derived from alkylation product 4 required hydrolysis to induce cyclization. Compounds1b‐1fwere obtained in this way. Compounds with a four carbon bridge were obtained by reaction of two equivalents of methyl α‐bromophenyl acetate and 1,4‐diaminobutane to produceN,N'‐bis‐[(α‐phenyl‐α‐methoxycarbonyl)methyl]butylenediamine6. The isothiocyanate or isocyanate adducts from 6 cyclized, without hydrolysis, to form compounds2a‐2e.
A facile synthesis of 3,5‐diaminopyrazole‐4‐carbothioamides and 3,5‐diaminopyrazole‐4‐carboxylates
Authors: Cocco Maria Teresa , Congiu Cenzo , Onnis Valentina , Bernard Angela Maria , Piras Pier Paolo
Published: February 2009

Simple and convenient synthesis of hitherto unknown 3,5‐diaminopyrazole‐4‐carbothioamides 3 as well as new ethyl 3,5‐diaminopyrazole‐4‐carboxylates 7 is reported. The key intermediates were 2‐cyano‐propenethioamides 2 and 2‐(ethoxycarbonyl)propenethioamides 5 which were readily obtained by reaction of phenyl isothiocyanate with 3‐(2‐acylhydrazino)‐3‐aminopropenenitriles 1 and ethyl 3‐(2‐acylhydrazino)‐3‐aminopropenoates 4 respectively. Intramolecular cyclization of compounds 2 afforded pyrazole‐4‐carbothioamides 3 while propenethioamides 5 gave pyrazole‐4‐carboxylates 7.
Convenient synthesis of 1,6,7,8‐substituted 2‐(3′,4′‐substituted‐phenyl)‐4‐quinolones via a 4‐ethoxyflavylium salt
Authors: Sato Shingo , Watanabe Takeshi , Kumagai Hironobu , Kitamura Nobuo , Matsuba Shigeru , Kumazawa Toshihiro , Onodera Jun‐Ichi , Suzuki Masanobu
Published: February 2009

Condensation of 2‐hydroxyacetophenone with benzaldehyde in the presence of 70% perchloric acid in ethyl orthoformate gave the corresponding 4‐ethoxyflavylium perchlorate, which was treated with aqueous ammonia or methylamine solution to afford 1,6,7,8‐substituted 2‐(3′,4′‐substituted‐phenyl)‐4‐quinolone in fair to good yield.
1,2,3‐Triazolo[4,5‐e]‐1,2,4‐triazolo[3,4‐c]pyrimidines
Authors: Biagi Giuliana , Giorgi Irene , Livi Oreste , Manera Clementina , Scartoni Valerio
Published: February 2009

Some new 1,2,3‐triazolo[4,5‐e]‐1,2,4‐triazolo[3,4‐c]pyrimidmes were prepared starting from the corresponding 1,2,3‐triazolo[4,5‐d]pyrimidines via the formation of the 1,2,4‐triazole ring. Thus suitable hydrazino derivatives 6 were condensed with triethyl orthoformate, triethyl orthoacetate and triethyl orthobenzoate to give the expected tricyclic derivatives 7, 8 and 9. Intramolecular cyclization of the ethoxycarbonylhydrazino derivatives 10 gave the tricyclic compounds 11 bearing an hydroxyl group in the 3 position. The v‐triazolo‐s‐triazolopyrimidine derivatives were tested towards the A1 and A2A adenosine receptors in binding assays, but they did not show any receptor affinity.
Ring transformations of heterocyclic compounds. XVIII . Spiro[cyclohexadiene‐indolines] with three stereocenters from pyrylium salts and chiral methyleneindolines — an example of a high diastereoselective ring transformation
Authors: Zimmermann Thomas , Abram Ulrich
Published: February 2009

The diastereoselective synthesis of 6‐aroyl‐3,5‐diarylspiro[cyclohexa‐2,4‐diene‐1,2′‐indolines] 4 possessing three stereocenters from 2,4,6‐triarylpyrylium perchlorates 1 and chiral methyleneindolines 3 (generated in situ by deprotonation of the corresponding 3H‐indolium perchlorates 2) in the presence of triethylamine/acetic acid in ethanol by a 2,5‐[C4+C2] pyrylium ring transformation is reported. Structure elucidation is performed by X‐ray structure determinations of the spiro[cyclohexadiene‐indolines] 4a, 4p and 4t. The influence of various substituents at C‐3 of the methyleneindolines 3 on the stereochemistry of the transformation, mechanistic details as well as spectroscopic data of the products 4 are discussed.
Behaviour of 5,6‐dihydrothieno[2,3‐h]cinnolin‐3(2H)‐one and 5,6‐dihydrothieno[3,2‐h]cinnolin‐3(2H)‐one towards hydrazine. Synthesis of thienocinnolinones and of 4‐aminothienocinnolinones
Authors: Villa Stefania , Cignarella Giorgio , Curzu Michela M. , Pinna Gérard A. , Pini Elena , Toma Lucio
Published: February 2009

The isomeric compounds 5,6‐dihydrothieno[2,3‐h]cinnolin‐3(2H)‐one (7a) and 5,6‐dihydrothieno‐[3,2‐h]cinnolin‐3(2H)‐one (7b) rapidly tautomerise to the corresponding 1,4‐dihydrothienocinnolinones 8a,b when kept in refluxing hydrazine hydrate. With longer reaction times the initially formed 8a,b dehydrogenate to the thienocinnolinones 9a,b which eventually are aminated to 4‐aminothienocinnolinones 10a,b. This behaviour recalls that reported for the related 5,6‐dihydrobenzocinnolin‐3(2H)‐one (1) which under the same conditions undergoes dehydrogenation to benzo[h]cinnolin‐3(2H)‐one (2) followed by 4‐amination to 3, but differs for the stability of the intermediates, for the mechanism of the final amination, and for the higher reaction rate. All these differences can be rationalised in terms of the heats of formation of the intermediates and products of the two series of transformations.
2,4,6‐Trichloropyrimidine. Reaction with sodium amide
Authors: Delia Thomas J. , Meltsner Bernard R. , Schomaker Jennifer M.
Published: February 2009

The first reaction between 2,4,6‐trichloropyrimidine 1 and anionic nitrogen nucleophiles is described. Treatment of 1 with one equivalent of sodium amide gave mixtures of 4‐amino‐2,6‐dichloropyrimidine 2 and 2‐amino‐4,6‐dichloropyrimidine 3. Additional quantities of sodium amide failed to provide either diamino‐ or triaminopyrimidines. Instead, the strongly basic nature of sodium amide led to higher molecular products that were not characterized.
Synthesis of novel quinoxaline‐5‐carboxylic acid derivatives
Authors: Kornberg Brian E. , Nikam Sham S. , Rafferty Michael F.
Published: February 2009

This paper describes the synthesis of several new 2,3‐dimethoxy‐6‐methyl‐7‐nitro‐quinoxaline‐5‐carboxylic acid derivatives (13a‐m) via a multistep synthetic route from 5‐methyl‐1H‐benzo[d][1,3]oxazine‐2,4‐dione (1).
Synthesis of 4,5‐dichloro‐1‐(4,5‐dichloropyridazin‐3‐yl)pyridazin‐6‐one
Authors: Kweon Deok‐Heon , Kang Young‐Jin , Chung Hyun‐A , Park Jung‐Won , Lee Woo Song , Yoon Yong‐Jin , Kim Sung‐Kyu , Shiro Motoo
Published: February 2009

This paper presents the synthesis of 4,5‐dichloro‐1‐(4,5‐dichloropyridazin‐3‐yl)pyridazin‐6‐one from 4,5‐dichloropyridazin‐6‐one.
Synthesis and X‐ray structure of new spiro‐imidazo[2,1‐b]thiazole
Authors: Feng Yaqing , Zhang Weihong , Chen Ligong , Froelich J. , Meretter K. , Sauter F.
Published: February 2009

Spiro[5,5]undecane‐3‐one 1 was converted to 4,7‐dihydrospiro[benzo[d]thiazole‐6(5H),1′‐cyclohexane]‐2‐amine 3, which is condensed with bromomethyl (halo)phenyl ketones and cyclized to compounds 5a‐5c. The X‐ray crystallography of the 5b reveals that formation route for 5 is via 3‐position‐substituted‐spiro‐iminothiazole 4.
Synthesis of 5‐cyanopyrazolo[3,4‐b]pyridines in the reaction of 5‐amino‐3‐methyl‐1‐phenylpyrazole with arylidene derivatives of malonodinitrile and ethyl cyanoacetate
Authors: Quiroga Jairo , Alvarado Mario , Insuasty Braulio , Moreno Rodolfo , Raviña Enrique , Estevez Isabel , De Almeida S. Regina H.
Published: February 2009

This paper describes the synthesis of a new series of 6‐amino‐4‐aryl‐5‐cyanopyrazolo[3,4‐b]pyridines 4 and 4‐aryl‐5‐cyano‐6H‐pyrazolo[3,4‐b]pyridin‐6‐ones 5 from the reaction of 5‐amino‐3‐methyl‐1‐phenylpyrazole 1 with arylidene derivatives of malonodinitrile 2 and ethyl cyanoacetate 3. The structure of the final compounds was determined on the basis of nmr measurements, especially by 1H, 1H‐, 1H, 13C‐COSY, DEPT and X‐ray diffraction.
A new selective preparation of ethyl 7‐aminopteridine‐6‐ carboxylate derivatives and related compound
Authors: Yamada Yoichi , Yasuda Heinosuke , Yoshihara Yuichi , Yoshizawa Kazue
Published: February 2009

A series of ethyl 7‐amino‐2,4‐dioxopteridine‐6‐carboxylates 4 and ethyl 7‐amino‐4‐oxo‐2‐thioxopteridine‐6‐carboxylates 5, of interest biologically, has been prepared in one step from the reaction of such vicinal‐diamines as 1,3‐dialkyl‐5,6‐diaminouracils 2 or 1,3‐dialkyl‐5,6‐diamino‐2‐thiouracils 3 with diethyl (E)‐2,3‐dicyanobutenedioate (1). Moreover, ethyl 3‐amino[1,2,4]triazino[2,3‐a]‐1H‐benzimidazole‐2‐carboxylate (11) was also obtained from the reaction between 1,2‐diamino‐1H‐benzimidazole (10) and 1. The structural studies of 4, 5, and 11 prepared were carried out by nmr experiments in some details.
Synthesis and reactivity of 1,2,4‐triazolo[1,5‐c]quinazolines
Authors: Pfeiffer Wolf‐Diethard , Bodtke Anja , Mücke Jana , Hetzheim Annemarie , Pazdera Pavel
Published: February 2009

The preparation of 1,2,4‐triazolo[1,5‐c]quinazolines 4a‐d, 5, 8a‐d by cyclocondensation of 1a‐c with carboxylic acids and carboxylic anhydrides, respectively, is described. By different pathways, the 5‐thioxo‐5,6‐dihydro‐1,2,4‐triazolo[1,5‐c]quinazolines 4a‐d react with hydrazine hydrate or amines with the formation of 5‐substituted 1,2,4‐triazolo[1,5‐c]quinazolines 9 and 10a‐d. Cyclocondensation of 9 with carboxylic acids, carboxylic anhydrides, and nitrous acid, respectively, leads to the new anellated heterocycles bis‐1,2,4‐triazolo[4,3‐a:1,5‐c]quinazoline 13 and tetrazolo [1,5‐a]‐1,2,4‐triazolo[1,5‐c]quinazoline (14).
New synthesis of substituted isoindolines from furans via epoxyisoindolines
Authors: Mance A. D. , Borovička B. , Karaman B. , Jakopčić K.
Published: February 2009

The preparation of substituted N‐arylisoindolines 3 from simple furan derivatives 1 is reported. Oxatricycloadducts 2, readily accessible by intramolecular Diels‐Alder reaction are susceptible to acidic reagents yielding aromatized products 3 by a ring‐opening reaction via intermediate carbocation.
Techniques of cardiac output measurement during liver transplantation: Arterial pulse wave versus thermodilution
Authors: Nissen Peter , Van Lieshout Johannes J. , Novovic Srdan , Bundgaard-Nielsen Morten , Secher Niels H.
Published: February 2009

In this study, we compared continuous cardiac output (CO) obtained from the femoral arterial pressure by simulation of an aortic input impedance model [model-simulated cardiac output (MCO)] to thermodilution cardiac output (TDCO) determined by bolus injection during liver transplantation. Both variables were measured in 39 adult patients (13 females) every 10th minute during liver transplant surgery. Paired measurements were compared during the 4 phases of surgery—dissection, anhepatic phase, early reperfusion (the first 15 minutes after reperfusion), and late reperfusion (15-60 minutes after reperfusion)—without the detection of any significant difference between the 2 estimates of CO. TDCO ranged from 2.3 to 17.2 L/minute, and the bias (the mean difference between MCO and TDCO) prior to calibration was −0.4 ± 1.6 L/minute (mean ± standard deviation; 1309 paired measurements; 95% limits of agreement: −3.4 to 2.6 L/minute). After calibration of the first determined MCO by the simultaneously determined TDCO, the bias was 0.1 ± 1.5 L/minute, with 57% (n = 744) of the comparisons being less than 1 L/minute and 35% (n = 453) being less than 0.5 L/minute; this was independent of the level of CO, and the mutual correlation coefficient was 0.812 (P < 0.001). This study indicates that during liver transplantation surgery, MCO reflects TDCO throughout the operation. Thus, for CO, this less invasive method appears to provide a reliable uninterrupted measurement during orthotopic liver transplantation.
Microdialysis monitoring of porcine liver metabolism during warm ischemia with arterial and portal clamping
Authors: Ungerstedt Johan , Nowak Greg , Ungerstedt Urban , Ericzon Bo-Göran
Published: February 2009

Early detection of vascular complications following liver surgery is crucial. In the present study, intrahepatic microdialysis was used for continuous monitoring of porcine liver metabolism during occlusion of either the portal vein or the hepatic artery. Our aim was to assess whether microdialysis can be used to detect impaired vascular inflow by metabolic changes in the liver. Changes in metabolite concentrations in the hepatic interstitium were taken as markers for metabolic changes. After laparotomy, microdialysis catheters were introduced directly into the liver, enabling repeated measurements of local metabolism. Glucose, lactate, pyruvate, and glycerol were analyzed at bedside every 20 minutes, and the lactate/pyruvate ratio was calculated. In the arterial clamping group, the glucose, lactate, glycerol, and lactate/pyruvate ratio significantly increased during the 2-hour vessel occlusion and returned to baseline levels during the 3-hour reperfusion. In the portal occlusion group and in the control group, the measured metabolites were stable throughout the experiment. Our findings show that liver metabolism, as reflected by changes in the concentrations of glucose, lactate, and glycerol and in the lactate/pyruvate ratio, is markedly affected by occlusion of the hepatic artery. Surprisingly, portal occlusion resulted in no major metabolic changes. In conclusion, the microdialysis technique can detect and monitor arterial vascular complications of liver surgery, whereas potential metabolic changes in the liver induced by portal occlusion were not seen in the current study. Microdialysis may thus be suitable for use in liver surgery to monitor intrahepatic metabolic changes.
Thermal‐ and Sun‐Promoted Generation of Silver Nanoparticles Embedded into Poly(vinyl alcohol) Films
Authors: Bernabò Marco , Pucci Andrea , Galembeck Fernando , Leite Carlos Alberto de Paula , Ruggeri Giacomo
Published: February 2009

Nanocomposites based on poly(vinyl alcohol) and silver nanoparticles were efficiently prepared by sun‐ and thermal‐promoted reduction processes. Uniaxial drawing of the Ag/PVA nanocomposites favoured the anisotropic distribution of silver particles, providing oriented films with polarisation‐dependent tunable optical properties. These dichroic properties were more pronounced for nanocomposites produced by sun exposition, which provided more compact and interacting metal clusters. The results obtained suggest the nanocomposite films could find potential applications as colour polarising filters, radiation responsive polymeric objects and smart flexible films in packaging applications.

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Vibrational spectroscopy of bare and solvated ionic complexes of biological relevance
Authors: Polfer Nick C. , Oomens Jos
Published: February 2009

The low density of ions in mass spectrometers generally precludes direct infrared (IR) absorption measurements. The IR spectrum of an ion can nonetheless be obtained by inducing photodissociation of the ion using a high‐intensity tunable laser. The emergence of free electron lasers (FELs) and recent breakthroughs in bench‐top lasers based on nonlinear optics have now made it possible to routinely record IR spectra of gas‐phase ions. As the energy of one IR photon is insufficient to cause dissociation of molecules and strongly bound complexes, two main experimental strategies have been developed to effect photodissociation. In infrared multiple‐photon dissociation (IR‐MPD) many photons are absorbed resonantly and their energy is stored in the bath of vibrational modes, leading to dissociation. In the “messenger” technique a weakly bound van der Waals atom is detached upon absorption of a single photon. Fundamental, historical, and practical aspects of these methods will be presented. Both of these approaches make use of very different methods of ion preparation and manipulation. While in IR‐MPD ions are irradiated in trapping mass spectrometers, the “messenger” technique is generally carried out in molecular beam instruments. The main focus of this review is the application of IR spectroscopy to biologically relevant molecular systems (amino acids, peptides, proteins). Particular issues that will be addressed here include gas‐phase zwitterions, the (chemical) structures of peptides and their collision‐induced dissociation (CID) products, IR spectra of gas‐phase proteins, and the chelation of metal–ligand complexes. Another growing area of research is IR spectroscopy on solvated clusters, which offer a bridge between the gas‐phase and solution environments. The development of state‐of‐the‐art computational approaches has gone hand‐in‐hand with advances in experimental techniques. The main advantage of gas‐phase cluster research, as opposed to condensed‐phase experiments, is that the systems of interest can be understood in detail and structural effects can be studied in isolation. It will be shown that IR spectroscopy of mass‐selected (bio)molecular systems is now well‐placed to address specific questions on the individual effect of charge carriers (protons and metal ions), as well as solvent molecules on the overall structure. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 28:468–494, 2009
Hyperglycemic choreoathetosis: Role of the putamen in pathogenesis
Authors: Kandiah Nagaendran , Tan Kevin , Lim C.C. Tchoyoson , Venketasubramanian Narayanaswamy
Published: February 2009

Hyperglycemic choreoathetosis (HC) is an uncommon syndrome often associated with hyperintensity of the basal ganglia on MRI. We performed a retrospective review of cases with HC to characterize the clinical, biochemical, and neuroimaging (CT, MRI, and MR spectroscopy) findings and to propose a mechanism for this syndrome. Seven HC patients with a mean age of 75.1 years, mean blood glucose of 27.4 mmol/L, and mean plasma osmolarity of 313.4 mmol/L were studied. All had MR‐T1 hyperintensity of the putamen on the side contralateral to the choreoathetosis. Two patients had additional hyperintensity of the globus pallidus while one also had involvement of the caudate. On MR‐T2, 2 patients showed hyperintensity, 2 isointensity, and 3 hypointensity in the putamen. MR spectroscopy showed elevated choline and reduced N‐acetylaspartate; two patients also had elevated myoinositol levels. Our findings suggest that the putamen has a central role in HC, and MR spectroscopy supports neuronal dysfunction in the putamen. Biochemical and neuroimaging findings support hyperviscosity as the most plausible mechanism. © 2009 Movement Disorder Society
Cysteine elevation in levodopa‐treated patients with Parkinson's disease
Authors: Müller Thomas , Kuhn Wilfried
Published: February 2009

Homocysteine, cysteine, and cysteinyl‐glycine are all metabolically interrelated. Levodopa/decarboxylase inhibitor (LD/DCI) administration increases total homocysteine (tHcy) plasma levels. Objectives were to investigate associations between LD/DCI intake, concentrations of tHcy, cysteine, and cysteinyl‐glycine in PD patients and healthy controls. Cysteine levels were significant lower in controls and PD patients with tHcy below the treshold of 15 [μmol/L] when compared with PD patients with tHcy above 15. Cysteinyl‐glycine did not significantly differ between the three cohorts. Significant associations appeared between tHcys and cysteine in PD patients. tHcy and cysteine concentrations correlated to LD/DCI intake and severity of PD. The cysteine increase may be due to the significant higher dosing of daily LD/DCI and the significant higher morning LD/DCI dose 1 hour before blood sampling in PD patients with tHcy above 15 when compared with the remaining PD patients and the controls. The correlation outcomes support the view that LD/DCI intake may also increase cysteine. © 2009 Movement Disorder Society
Technical note: Traffic intensity estimation
Authors: Kiessler Peter C. , Lund Robert
Published: February 2009

This note examines estimation of the traffic intensity in an M/G/1 queue. We show that the ratio of sample mean service times to the sample mean interarrival times has undesirable sampling properties. To remedy this, two alternative estimators are introduced. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009
Space‐Mapping and Optimal Shape Design
Authors: Marburger Jan
Published: February 2009

Optimal shape design is a common problem in practice. In most cases this means that a complex geometry has to be optimized such that it satisfies a desired quantity. The direct optimization is very difficult and time consuming, if it is possible at all. Therefore, often only simplified models are derived and optimized. In general this does not yield an optimal solution. For this reason the space–mapping method is introduced, which combines the results of the complex model, e.g. a 3D model, and a simplified model, e.g. a 1D or 2D model. The derivation of a simplified model of a filter device and the following optimization is presented. Finally, the advantages of the space–mapping method applied to this example is shown. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimal PID controller of robots under stochastic uncertainty
Authors: Schacher Michael
Published: February 2009

In practice often it is not possible to specify exact model parameters. Hence, precomputed controller based on some parameter estimates can produce bad results.

In this presentation the aim is to combine classical PID control theory and stochastic optimisation methods in order to obtain robust optimal feedback control.

The method works with cost functions being minimized and takes into account stochastic parameter varations.

After Taylor expansion to calculate expected cost functions and a few transformations an approximate deterministic substitute PID control problem follows. Here, retaining only linear terms, approximation of expectations and variances of the expected cost functions can be calculated explicitly. By means of splines, numerical approximations of the objective function and the differential equations are obtained then.

Using stochastic optimization methods, random parameter variations are incorporated into the optimal control process. Hence, robust optimal feedback controls are obtained. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)