bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diastereoselective Additions to C—C Double Bonds Applied to the Enantioselective Synthesis of Pyrethroic Acids
Authors: Krief Alain , Froidbise Alexandre 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Iodine in Organic Synthesis
Authors: Banerjee Ajoy K. , Vera William , Mora Henry , Laya Manuel S. , Bedoya Liadis , Cabrera Elvia V. 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Palladium‐Mediated Cascade or Multicomponent Reactions: A New Route to Carbo‐ and Heterocyclic Compounds
Authors: Balme Genevieve , Bouyssi Didier , Monteiro Nuno 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Asymmetric Synthesis of Hydroxylated Pyrrolidines, Piperidines and Related Bioactive Compounds: From N‐Acyliminium Chemistry to N‐α‐Carbanion Chemistry
Authors: Huang Pei‐Qiang 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Novel Synthetic Protocol for Supramolecules and Polymers by Molecular Construction and Integration Based on Dynamic Covalent Chemistry
Authors: Takata Toshikazu , Otsuka Hideyuki 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
The Predicted 3D Structures of the Human M1 Muscarinic Acetylcholine Receptor with Agonist or Antagonist Bound
Authors: Peng Joyce Yao‐chun , Vaidehi Nagarajan , Hall Spencer E. , Goddard William A. 
Published: August 2006

AbstractThe muscarinic acetylcholine G‐protein‐coupled receptors are implicated in diseases ranging from cognitive dysfunctions to smooth‐muscle disorders. To provide a structural basis for drug design, we used the MembStruk computational method to predict the 3D structure of the human M1 muscarinic receptor. We validated this structure by using the HierDock method to predict the binding sites for three agonists and four antagonists. The intermolecular ligand–receptor contacts at the predicted binding sites agree well with deductions from available mutagenesis experiments, and the calculated relative binding energies correlate with measured binding affinities. The predicted binding site of all four antagonists is located between transmembrane (TM) helices 3, 4, 5, 6, and 7, whereas the three agonists prefer a site involving residues from TM3, TM6, and TM7. We find that Trp 157(4) contributes directly to antagonist binding, whereas Pro 159(4) provides an indirect conformational switch to position Trp 157(4) in the binding site (the number in parentheses indicates the TM helix). This explains the large decrease in ligand binding affinity and signaling efficacy by mutations of Trp 157(4) and Pro 159(4) not previously explained by homology models. We also found that Asp 105(3) and aromatic residues Tyr 381(6), Tyr 404(7), and Tyr 408(7) are critical for binding the quaternary ammonium head group of the ligand through cation–π interactions. For ligands with a charged tertiary amine head group, we suggest that proton transfer from the ligand to Asp 105(3) occurs upon binding. Furthermore, we found that an extensive aromatic network involving Tyr 106(3), Trp 157(4), Phe 197(5), Trp 378(6), and Tyr 381(6) is important in stabilizing antagonist binding. For antagonists with two terminal phenyl rings, this aromatic network extends to Trp 164(4), Tyr 179(extracellular loop 2), and Phe 390(6) located at the extracellular end of the TMs. We find that Asn 382(6) forms hydrogen bonds with selected antagonists. Tyr381(6) and Ser 109(3) form hydrogen bonds with the ester moiety of acetylcholine, which binds in the gauche conformation.
Apoptosis in the developing mouse heart
Authors: Barbosky Laura , Lawrence David K. , Karunamuni Ganga , Wikenheiser Jamie C. , Doughman Yong‐Qiu , Visconti Richard P. , Burch John B.E. , Watanabe Michiko 
Published: August 2006

AbstractApoptosis occurs at high frequency in the myocardium of the developing avian cardiac outflow tract (OFT). Up‐ or down‐regulating apoptosis results in defects resembling human conotruncal heart anomalies. This finding suggested that regulated levels of apoptosis are critical for normal morphogenesis of the four‐chambered heart. Recent evidence supports an important role for hypoxia of the OFT myocardium in regulating cell death and vasculogenesis. The purpose of this study was to determine whether apoptosis in the outflow tract myocardium occurs in the mouse heart during developmental stages comparable to the avian heart and to determine whether differential hypoxia is also present at this site in the murine heart. Apoptosis was detected using a fluorescent vital dye, Lysotracker Red (LTR), in the OFT myocardium of the mouse starting at embryonic day (E) 12.5, peaking at E13.5–14.5, and declining thereafter to low or background levels by E18.5. In addition, high levels of apoptosis were detected in other cardiac regions, including the apices of the ventricles and along the interventricular sulcus. Apoptosis in the myocardium was detected by double‐labeling with LTR and cardiomyocyte markers. Terminal deoxynucleotidyl transferase–mediated deoxyuridinetriphosphate nick end‐labeling (TUNEL) and immunostaining for cleaved Caspase‐3 were used to confirm the LTR results. At the peak of OFT apoptosis in the mouse, the OFT myocardium was relatively hypoxic, as indicated by specific and intense EF5 staining and HIF1α nuclear localization, and was surrounded by the developing vasculature as in the chicken embryo. These findings suggest that cardiomyocyte apoptosis is an evolutionarily conserved mechanism for normal morphogenesis of the outflow tract myocardium in avian and mammalian species. Developmental Dynamics 235:2592–2602, 2006. © 2006 Wiley‐Liss, Inc.
Luminescent Open‐Framework Antiferromagnet – Hydrothermal Syntheses, Structures, and Luminescent and Magnetic Properties of Two Novel Coordination Polymers: [Zn(pdoa)(bipy)]n and {[Mn(pdoa)(bipy)](bipy)}n [pdoa = 2,2′‐(1,3‐phenylenedioxy)bis(acetate); bipy = 4,4′‐bipyridine]
Authors: Hong Xian‐Lan , Bai Junfeng , Song You , Li Yi‐Zhi , Pan Yi 
Published: August 2006

AbstractTwo coordination polymers of mixed ligands, 2,2′‐(1,3‐phenylenedioxy)bis(acetate) (pdoa) and 4,4′‐bipyridine (bipy),namely [Zn(pdoa)(bipy)]n (1) and {[Mn(pdoa)(bipy)](bipy)}n (2), have been hydrothermally synthesized and characterized by single‐crystal X‐ray diffraction and IR spectra. Complex 1 crystallizes in the triclinic space group P with a = 6.8826(18) Å, b = 11.202(3) Å, c = 12.295(3) Å, α = 86.854(4)°, β = 85.759(5)°, γ = 72.629(4)° and is a novel folded‐paper‐shaped coordination compound with polymeric sheets formed by the five‐coordinate ZnII centers and bridging pdoa and bipy. Complex 2 crystallizes in the monoclinic space group P21/c with a = 11.507(2) Å, b = 23.254(5) Å, c = 9.8710(19) Å, β = 96.418(4)° and exhibits a robust three‐dimensional framework with nanosized rectangular channels (11.627 × 11.507 Å). They both display blue fluorescent emission and could be considered as new luminescent materials. In addition, the magnetic properties of complex 2 were investigated and the magnetic susceptibility data were rationally fitted with g = 2.072(5), J = –1.11(4) cm–1, and zJ′ =–0.161(7) cm–1, showing it is an unprecedented luminescent open‐framework antiferromagnet.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Application of palm olein in the production of zero‐trans Iranian vanaspati through enzymatic interesterification
Authors: Farmani Jamshid , Safari Mohammad , Hamedi Manouchehr 
Published: August 2006

AbstractThe utilization of palm olein in the production of zero‐trans Iranian vanaspati through enzymatic interesterification was studied. Vanaspati fat was made from ternary blends of palm olein (POL), low‐erucic acid rapeseed oil (RSO) and sunflower oil (SFO) through direct interesterification of the blends or by blending interesterified POL with RSO and SFO. The slip melting point (SMP), the solid fat content (SFC) at 10–40 °C, the carbon number (CN) triacylglycerol (TAG) composition, the induction period (IP) of oxidation at 120 °C (IP120) and the IP of crystallization at 20 °C of the final products and non‐interesterified blends were evaluated. Results indicated that all the final products had higher SMP, SFC, IP of crystallization and CN 48 TAG (trisaturated TAG), and lower IP120, than their non‐interesterified blends. However, SMP, SFC, IP120, IP of crystallization and CN 48 TAG were higher for fats prepared by blending interesterified POL with RSO and SFO. A comparison between the SFC at 20–30 °C of the final products and those of a commercial low‐trans Iranian vanaspati showed that the least saturated fatty acid content necessary to achieve a zero‐trans fat suitable for use as Iranian vanaspati was 37.2% for directly interesterified blends and 28.8% for fats prepared by blending interesterified POL with liquid oils.
Fire behaviour of plastic parts in electrical appliances—standards versus required fire safety objectives
Authors: Babrauskas Vytenis , Simonson Margaret 
Published: August 2006

AbstractFor most categories of consumer electrical appliances, UL and IEC standards are typically the only widely used safety standards. A number of these standards are examined to determine if they incorporate technical provisions so that complying products would thereby meet expected fire safety objectives. Specifically, the provisions are examined governing plastic parts in electrical appliances. It is found that the standards do not consistently contain provisions that would, by themselves, suffice for a designer to produce a fire‐safe design. Instead, major shortcomings exist, and if an appliance were designed solely to meet the standards and without any additional fire safety considerations, it would not have a reasonable degree of safety. A typical outcome could be a product which is readily ignitable by a small external ignition source and which shows fierce burning upon being so ignited. Furthermore, an internal electrical fault in such a product would probably not be contained within the unit and, rather, would spread to its easily combustible exterior surfaces and produce a similar, fierce fire. It is urged that UL and IEC standards be upgraded so that compliance with the standards would carry a reasonable assurance that fire safety objectives have been met. The recommendations made are intended to cover all UL and IEC appliance standards, not limited to the example cases considered. Copyright © 2006 John Wiley & Sons, Ltd.
Morphology and alkaloidal profile of the seedlings of Erythrina americana MILL. and E. coralloides A.DC.
Authors: San Miguel‐Chávez R. , Soto‐Hernández M. , Terrazas T. , Kite G. 
Published: August 2006

AbstractThe morphological characteristics and the alkaloid content of seedlings of the closely related Erythrina americana and E. coralloides were studied in order to document new taxonomic evidence for the separation of these species. Seedlings of E. americana have a slim hypocotyl, opposed trifoliate juvenile leaves with entire margin and acuminated apex. The seedlings of E. coralloides are distinguished by a hypocotyl that becomes swollen, grooved and curved during growth, and opposed unilobate juvenile leaves with whole margin and mucronated apex. Moreover, leaves, hypocotyls and roots develop in a different manner in each species. The alkaloids erysosalvine, erythraline‐N‐oxide, erythrartine and 8‐oxo‐α‐erythroidine are present only in seedlings of E. americana, whilst erythraline and erysopine are exclusive to E. coralloides . It is reasoned that the morphological and chemical evidence revealed in this study supports the recognition of both taxa as independent species. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Seed morphology of Cuscuta L. (Convolvulaceae) in Egypt and its systematic significance
Authors: Abdel Khalik K. N. 
Published: August 2006

AbstractThe seed morphology of eight taxa of Cuscuta from Egypt has been studied using light and scanning electron microscopy, to determine the significance of seed coat features as taxonomic characters. Macro‐ and micromorphological characters, including seed shape, colour, size, epidermal cell shape, anticlinal boundaries, outer periclinal cell wall and relief of outer cell walls are presented. Three types of anticlinal cell wall boundaries are recognized and two different shapes of outer periclinal cell wall are described. The secondary sculpture of the cell wall varies from striate to micro‐reticulate, and smooth to fine folds. A key for the identification of the investigated taxa based on seed characters is provided. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Distributed and integrated response of a geographic information system‐based hydrologic model in the eastern Palouse region, Idaho
Authors: Brooks Erin S. , Boll Jan , McDaniel Paul A. 
Published: August 2006

AbstractVerification of distributed hydrologic models is rare owing to the lack of spatially detailed field measurements and a common mismatch between the scale at which soil hydraulic properties are measured and the scale of a single modelling unit. In this study, two of the most commonly calibrated parameters, i.e. soil depth and the vertical distribution of lateral saturated hydraulic conductivity Ks, were eliminated by a spatially detailed soil characterization and results of a hillslope‐scale field experiment. The soil moisture routing (SMR) model, a geographic information system‐based hydrologic model, was modified to represent the dominant hydrologic processes for the Palouse region of northern Idaho. Modifications included Ks as a double exponential function of depth in a single soil layer, a snow accumulation and melt algorithm, and a simple relationship between storage and perched water depth (PWD) using the drainable porosity. The model was applied to a 2 ha catchment without calibration to measured data. Distributed responses were compared with observed PWD over a 3‐year period on a 10 m × 15 m grid. Integrated responses were compared with observed surface runoff at the catchment outlet. The modified SMR model simulated the PWD fluctuations remarkably well, especially considering the shallow soils in this catchment: a 0·20 m error in PWD is equivalent to only a 1·6% error in predicted soil moisture content. Simulations also captured PWD fluctuations during a year with high spatial variability of snow accumulation and snowmelt rates at upslope, mid‐slope, and toe slope positions with errors as low as 0·09 m, 0·12 m, and 0·12 m respectively. Errors in distributed and integrated model simulations were attributed mostly to misrepresentation of rain events and snowmelt timing problems. In one location in the catchment, simulated PWD was consistently greater than observed PWD, indicating a localized recharge zone, which was not identified by the soil morphological survey. Copyright © 2006 John Wiley & Sons, Ltd.
Assessing regional land‐use/cover influences on New Jersey Pinelands streamflow through hydrograph analysis
Authors: Dow Charles L. 
Published: August 2006

AbstractRelative baseflow volume and streamflow flashiness indices were used to assess relationships between land use/cover and streamflow regime in nine New Jersey (NJ) Pinelands streams. Baseflow index (BFI) and Richards–Baker flashiness index (RBI) were estimated on an October–September water year, with period‐of‐record changes assessed by trend analysis and differences between watersheds assessed by examining index versus land‐use/cover relationships using a data period common to all study sites. Four streams, among the more urbanized watersheds of the nine study sites, were found to have significant (α = 0·05) trends in both indices. The two most urbanized study sites showed decreasing baseflow and increasing flashiness; however, the other two streams showed the opposite trends. An apparent slowdown in urbanization towards the second half of the streamflow period of record, along with potential changes in wetland agricultural practices in the latter two watersheds, may explain their trend results. A marginally significant (α = 0·10) decreasing relationship was found between mean annual BFI and wetland agriculture, whereas a significant (α = 0·05) increasing relationship was determined between mean annual RBI and artificial lakes/reservoirs. Principal component analysis showed an association between wetland agriculture and artificial lakes/reservoirs which suggested that both of the significant index versus land‐use/cover relationships reflect wetland agricultural activities. Because these significant relationships involved land uses/covers with small spatial extents (⩽5%), they demonstrated that land‐use practices can have a greater impact than spatial extent on stream hydrology. This study is the first step in assessing the effect on the NJ Pinelands stream ecology by streamflow alteration due to wetland agricultural activities. Copyright © 2006 John Wiley & Sons, Ltd.
Methyl‐CpG binding proteins are involved in restricting differentiation plasticity in neurons
Authors: Setoguchi Hiroki , Namihira Masakazu , Kohyama Jun , Asano Hirotsugu , Sanosaka Tsukasa , Nakashima Kinichi 
Published: August 2006

AbstractNeurons and astrocytes are generated from common neural precursors, yet neurogenesis precedes astrocytogenesis, which normally commences at later stages of development. We have previously reported that a particular cytosine residue within a STAT3‐binding site in the astrocyte‐specific marker glial fibrillary acidic protein (GFAP) gene promoter becomes demethylated in neuroepithelial cells as gestation proceeds. This demethylation correlates tightly with the onset of astrocyte differentiation, suggesting that a change in DNA methylation at cell‐type‐specific gene promoters controls the switch from neurogenesis to astrocytogenesis in the developing brain. Here, we show that late‐gestation neuroepithelial cells, which have already lost the methylation in the STAT3‐binding site within the GFAP promoter, can still give rise to neurons and that these neurons do not respond to a STAT3‐activating cytokine to express GFAP. Members of a transcriptional repressor family, the methylated‐CpG binding proteins (MBDs), including MeCP2, are predominantly expressed in neurons, and ectopic MeCP2 expression inhibited astrocyte differentiation of neuroepithelial cells. Moreover, we found that exon 1 of the GFAP gene remains hypermethylated even in neuroepithelial cells at a late developmental stage and in neurons differentiated from such neuroepithelial cells. We further demonstrate that MeCP2 actually binds to the highly methylated exon 1 of the GFAP gene in neurons. These results suggest that region‐specific DNA methylation and MBDs play an important role in the regulation of differentiation plasticity in neurons. © 2006 Wiley‐Liss, Inc.
Gene expression and protein localization of calmodulin‐dependent phosphodiesterase in adult rat retina
Authors: Santone Rocco , Giorgi Mauro , Maccarone Rita , Basso Manuela , Deplano Stefania , Bisti Silvia 
Published: August 2006

AbstractCalcium calmodulin‐dependent cyclic nucleotide phosphodiesterase (PDE1) was identified in crude extract and immunolabeled sections of rat retina. Both cAMP and cGMP PDE activities were stimulated by calcium‐calmodulin (4.7‐fold and 2.3‐fold, respectively). To characterize PDE1 isoforms in retinal cells further, we used antibodies that specifically recognize PDE1 gene products. PDE1B antibody stained a band at molecular mass of 63 kDa whereas PDE1C antibody recognized two bands at 74‐ and 70‐kDa molecular masses. Two PDE1A antibodies (against N‐terminal and C‐terminal peptides) detected a band at 79 kDa never described before. Immunohistochemical analysis showed a distribution of PDE1A in the outer retina with a bright fluorescence in the outer segments of photoreceptors. PDE1B is uniformly distributed across the retina. PDE1C is confined mainly to the inner retina, with a precise localization in the inner nuclear layer. Immunostaining with choline acetyltransferase antibody indicates localization in cholinergic amacrine cell. The present data provide evidence of expression of PDE1 isoforms in mammalian retina with a complementary distribution of PDE1A and PDE1C, suggesting different roles in retinal function. © 2006 Wiley‐Liss, Inc.
Phonon confinement studies in nanocrystalline anatase‐TiO2 thin films by micro Raman spectroscopy
Authors: Balaji S. , Djaoued Y. , Robichaud J. 
Published: August 2006

AbstractRaman studies were performed on titania thin films prepared by polyethylene glycol (PEG) assisted, low‐temperature, sol–gel method. The Raman spectra of the films show a systematic blue shift in the peak position and a broadening in the full width at half‐maximum (FWHM) when compared with those of the bulk anatase TiO2 powder. Several reports have appeared indicating this kind of peak shift and broadening of FWHM, which were attributed to the confinement of phonons in the anatase nanocrystallites. In this paper, we report an analysis of quantum size effect in the Raman spectra of nanocrystalline TiO2 thin films performed by utilizing the phonon dispersion relation of the anatase phase which has been obtained from a work based on density functional perturbation theory (DFPT). For comparison purposes the quantum size effect calculations have also been done utilizing the dispersion relations of the rutile phase. There is good agreement between the crystallite sizes evaluated from the equally weighted Raman line intensity of the dispersion relations obtained from the DFPT and those determined by X‐ray diffraction. Copyright © 2006 John Wiley & Sons, Ltd.
Comparison of two capillary electrophoresis online stacking modes by analysis of polycyclic aromatic hydrocarbons in airborne particulates
Authors: Song Guan‐Qun , Peng Zhen‐Lei , Lin Jin‐Ming 
Published: August 2006

AbstractNaphthalene, fluorene, pyrene, anthracene, phenanthrene, and chrysene were successfully separated by CD‐modified MEKC (CD‐MEKC) using 20 mM borate (pH 9.0) containing 90 mM SDS and 75 mM β‐CD. Two online stacking methods, i. e., sweeping and field‐enhanced sample injection (FESI), were explored to enhance the detection sensitivity. The influences of some crucial parameters in sweeping and FESI procedures were investigated. For FESI method, a plug of water and low‐conductivity sample matrix was used to increase the stacking efficiency. Compared with the sweeping method, FESI can increase the sensitivity in the range of 10–20‐fold. The proposed method was used for the analysis of polycyclic aromatic hydrocarbons in airborne particulates.