bluuebunny/crossref_metadata_2025_split huggingface dataset:
Peculiarities of the Synthesis of Lithium Ion Conducting Lanthanum Tantalate by Solid‐State Reaction and Precipitation from Solutions
Authors: Belous Anatolii , Gavrilenko Oksana , Pashkova Olena , Galven Cyrille , Bohnké Odile 
Published: March 2006

AbstractSynthesis of lithium ion conducting tantalates has been carried out by conventional solid‐state reaction (SSR) techniques and by precipitation from solutions (PS). It is shown that the latter chemical route leads to the formation of a pure perovskite phase, made up of nanosized particles, and uses milder conditions when compared with the solid‐state reaction technique. Thermal analyses, X‐ray powder diffraction (XRD) and infrared (IR) spectroscopy are used to investigate the phase transformations that occur during the preparation of these tantalates from powder precursors. After sintering, the nanosized particles of the powder obtained by the (PS) route are preserved and pellets with good compactness (89 %) are obtained. The electrical properties of the sintered ceramics have been investigated by ac impedance spectroscopy. These experiments showed that the total ionic conductivity (bulk and grain boundaries) of the (PS) pellet is slightly lower than that of the (SSR) pellet. This decrease of conductivity is attributed to an enhancement of the blocking effect of the grain boundaries resulting from the microstructure of the fine‐grain ceramics. The bulk conductivity is not affected by the synthetic route. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
The First Example of a Dinuclear Platinum(III) Complex with Three Bridging Ligands
Authors: Pellicani Raffaella Z. , Intini Francesco P. , Maresca Luciana , Mesto Ernesto , Pacifico Concetta , Natile Giovanni 
Published: March 2006

AbstractThe first triply bridged dinuclear platinum(III) compound with acetamidate ligands, X[Pt2Cl4{N(H)C(CH3)O}3] (X = K+ or AsPh4+), has been isolated in the solid state and characterized by one‐ and two‐dimensional NMR spectroscopy and X‐ray crystallography. Owing to the asymmetry of the bridging acetamidate ligands, three isomers can be formed (HHH, HHT, and HTH), although only two are found in the crude reaction product: HHT and HTH. The HTH species is thermodynamically less stable and slowly (half life of around two days at room temperature) isomerizes into the HHT form. The more stable and less symmetric HHT isomer crystallizes from chloroform/pentane (AsPh4+ counter ion). The two [Pt2Cl4{N(H)C(CH3)O}3]– anions of the unit cell are linked by two strong N–H···O H‐bonds while contiguous anions of adjacent cells are linked together by two, slightly weaker N–H···Cl H‐bonds. The result is a chain of anions running along the a direction. The crystal packing allows for the formation of one‐dimensional pore channels, also running along the a direction, which are filled with disordered pentane molecules. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Formation of Two 1D Polymeric Water Morphologies
Authors: Li Feng , Li Tao‐Hai , Su Wei , Gao Shui‐Ying , Cao Rong 
Published: March 2006

AbstractTwo complexes with double‐ or triple‐stranded chain structures, {[Cd(pg)(phen)]·3H2O}n (1) and {[Cd3(cpg)3(phen)2]·3H2O}n (2), have been hydrothermally synthesized [H2pg = 3‐phenylglutaric acid, H2cpg = 3‐(4‐chlorophenyl)glutaric acid, phen = 1,10‐phenanthroline]. In the crystal lattices of 1 and 2, two 1D polymeric water morphologies are observed (a treelike chain for 1 and a staircaselike tape for 2), both of which contain (H2O)6 subunits. The geometrical parameters of water chains and tapes are similar to those in ice, Ih, and liquid water, respectively. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis and Conformational Analysis of Saturated cis‐and trans‐1,3,2‐Benzodiazaphosphinine 2‐Oxides
Authors: Zalán Zita , Kivelä Henri , Lázár László , Fülöp Ferenc , Pihlaja Kalevi 
Published: March 2006

AbstractBy cyclization of N‐unsubstituted, and N1‐ or N3‐methyl‐substituted cis‐ and trans‐2‐(aminomethyl)cyclohexylamines with phenylphosphonic dichloride, phenyl dichlorophosphate and bis(2‐chloroethyl)phosphoramidic dichloride, P epimeric diastereomers a and b of the corresponding 1,3‐unsubstituted and 1‐ or 3‐methyl‐substituted 2‐phenyl‐, 2‐phenoxy‐ and 2‐[bis(2‐chloroethyl)amino]decahydro‐1,3,2‐benzodiazaphosphinine 2‐oxides have been synthesized. The stereochemistry and conformations of the prepared saturated 1,3,2‐benzodiazaphosphinine 2‐oxides were determined by 1H, 13C and 31P NMR spectroscopy aided by DFT geometry optimizations and J‐coupling‐constant calculations for selected structures. The 2‐phenoxy‐substituted trans‐fused derivatives with an equatorial phenoxy group in a hypothetical double‐chair conformation (14a, 16a, 18a) were observed to adopt nonchair heteroring conformations with a pseudoaxial P–OPh bond instead. The corresponding b epimers, as well as the trans‐fused 2‐phenyl and 2‐[bis(2‐chloroethyl)amino] derivatives (both P epimers) were found to retain double‐chair conformations. In the cis‐fused series, the position of the N‐in/N‐out equilibrium was dependent on the steric and stereoelectronic requirements of the phosphorus substituents (and thus on the phosphorus configuration) as well as on the substituents at the ring nitrogen atoms. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Dendritic Encapsulation – “Postsynthetic” Functionalizations of a Single Benzophenone Shielded by Shape‐Persistent Polyphenylene Dendrons
Authors: Bernhardt Stefan , Baumgarten Martin , Müllen Klaus 
Published: March 2006

AbstractFirst‐ and second‐generation polyphenylene dendrimers were synthesized starting from benzophenone as core. Variation of the size and the density of the dendrimer shell resulted in different isolation of the cores. To investigate the effect of shielding upon the reactivity of the core, chemical functionalizations as well as the alkali‐metal reduction of the encapsulated benzophenone core were performed. The herein presented synthetic concept opens the way to spatially well‐defined spherical nanoparticles bearing a single isolated function in the center. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis of 5a‐α‐Tocopheryl Azide and Its Reaction to 1‐(5a‐α‐Tocopheryl)‐1,2,3‐triazols by [2+3]‐Cycloaddition
Authors: Adelwöhrer Christian , Rosenau Thomas , Kloser Elisabeth , Mereiter Kurt , Netscher Thomas 
Published: March 2006

Abstract1,2,3‐Triazoles with 1‐position substituents, derived from α‐tocopherol (vitamin E), were synthesized by 1,3‐dipolar cycloaddition reactions of 5a‐azido‐α‐tocopheryl acetate with alkynes, and were fully analytically characterized. NMR spectra of the compounds and crystal structures of derivatives with a truncated isoprenoid side chain are presented. The tocopheryl moiety is readily cleaved in basic media, as a prerequisite for the use in delivery systems showing pH‐dependent drug release. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis of Aromatic Analogs of 8(S)‐HETE and Their Biological Evaluation as Activators of the PPAR Nuclear Receptors
Authors: Caijo Frédéric , Mosset Paul , Grée René , Audinot‐Bouchez Valérie , Boutin Jean , Renard Pierre , Caignard Daniel‐Henri , Dacquet Catherine 
Published: March 2006

AbstractA new family of 8‐HETE analogs has been synthesized as dual PPAR α and γ agonists. A versatile strategy has been developed to allow modulations not only around the aromatic core but also on the side chains of these analogs. The affinity of these compounds towards the PPARα and PPARγ receptors is reported, together with their transactivation percentage. The derivatives having a propargylic type side chain gave the most promising results as dual agonists. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Photoinduced Nucleophilic Substitution of Aryl Halides with Potassium Thioacetate – A One‐Pot Approach to Aryl Methyl and Diaryl Sulfides
Authors: Schmidt Luciana C. , Rey Valentina , Peñéñory Alicia B. 
Published: March 2006

AbstractAryl methyl sulfides and diaryl sulfides were prepared by photoinduced reactions of potassium thioacetate with aryl halides under entrainment conditions. Without isolation, the arene thiolates obtained by the aromatic substitution were quenched with methyl iodide to afford the aryl methyl sulfides in 26–59 % yields in a “one‐pot” procedure together with the diaryl sulfides in variable yields (3–31 %). By optimization of the reaction conditions it was possible to improve the formation of the Ar2S, going from moderate to good yields (64–83 %). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Calculating the optimal number of contaminant samples by means of data worth analysis
Authors: Norberg Tommy , Rosén Lars 
Published: March 2006

AbstractThis is a study of Bayesian data worth analysis in environmental clean‐up applications. Its focus is on calculating the worth of simultaneously taking several (soil) samples in a small homogeneous area and on finding the optimal number of samples to take, by relating the reduction in risk cost from sampling, that is, data worth, to the cost of the samples. Even though the cost of one sample may be higher than the risk cost reduction it provides, this study shows that several samples may be cost‐efficient. This is mainly due to two factors: one is that the unit sample cost often decreases as the number of samples increase; another, more important, factor is that the data worth of several samples typically is higher than the worth of fewer samples. Copyright © 2006 John Wiley & Sons, Ltd.
A systematic review and quantitative appraisal of fMRI studies of verbal fluency: Role of the left inferior frontal gyrus
Authors: Costafreda Sergi G. , Fu Cynthia H.Y. , Lee Lucy , Everitt Brian , Brammer Michael J. , David Anthony S. 
Published: March 2006

AbstractThe left inferior frontal gyrus (LIFG) has consistently been associated with both phonologic and semantic operations in functional neuroimaging studies. Two main theories have proposed a different functional organization in the LIFG for these processes. One theory suggests an anatomic parcellation of phonologic and semantic operations within the LIFG. An alternative theory proposes that both processes are encompassed within a supramodal executive function in a single region in the LIFG. To test these theories, we carried out a systematic review of functional magnetic resonance imaging studies employing phonologic and semantic verbal fluency tasks. Seventeen articles meeting our pre‐established criteria were found, consisting of 22 relevant experiments with 197 healthy subjects and a total of 41 peak activations in the LIFG. We determined 95% confidence intervals of the mean location (x,y, andzcoordinates) of peaks of blood oxygenation level‐dependent (BOLD) responses from published phonologic and semantic verbal fluency studies using the nonparametric technique of bootstrap analysis. Significant differences were revealed in dorsal–ventral (z‐coordinate) localizations of the peak BOLD response: phonologic verbal fluency peak BOLD response was significantly more dorsal to the peak associated with semantic verbal fluency (confidence interval of difference: 1.9–17.4 mm). No significant differences were evident in antero–posterior (x‐coordinate) or medial–lateral (y‐coordinate) positions. The results support distinct dorsal–ventral locations for phonologic and semantic processes within the LIFG. Current limitations to meta‐analytic integration of published functional neuroimaging studies are discussed. Hum Brain Mapp, 2006. © 2006 Wiley‐Liss, Inc.
Regional brain variations of cytochrome oxidase activity in Relnrl‐orl mutant mice
Authors: Strazielle C. , Hayzoun K. , Derer M. , Mariani J. , Lalonde R. 
Published: March 2006

AbstractCell malpositioning has been described in laminated structures of the spontaneous mutation, reeler, including the cerebellum, the hippocampus, and the neocortex. Despite the ectopic positions of different neuronal populations, the specificity of synaptic connections is maintained. The metabolic consequences of this form of neuropathology were examined in Relnrl mutant mice by quantitative measures of cytochrome oxidase (CO) activity, a mitochondrial enzyme essential for oxidative metabolism in neurons. Despite severe tissue disorganization but in line with the intact synaptic organization, the reeler mutation did not affect global metabolic activity of the laminated structures of the brain. CO activity, however, was altered in specific subregions of the cerebellum, hippocampus, and neocortex, as well as in septum and various brainstem (medial pontine, paramedial reticular, paragigantocellular reticular) regions anatomically related to these structures, attesting to large functional alterations in Relnrl‐orl brain. Metabolic activity variations were also detected in the ventral tegmental area and ventral neostriatum of the mesolimbic dopaminergic pathway. The results are discussed and compared to the regional CO variations found in other ataxic mice, in regard to the structural defects, the integrity of the connections, and the mutation‐specific effects. © 2006 Wiley‐Liss, Inc.
Characterization and location of secretory phospholipase A2 groups IIE, V, and X in the rat brain
Authors: Kolko Miriam , Christoffersen Nanna R. , Barreiro Sebastian G. , Miller Martin L. , Pizza Andrew J. , Bazan Nicolas G. 
Published: March 2006

AbstractSecretory phospholipases A2 (sPLA2) form a diverse family of enzymes involved in a variety of physiologic and pathologic processes. Common among all sPLA2 is the ability to cleave the second position of phospholipids, thereby releasing fatty acid and a lysophospholipid. Several sPLA2 have been cloned and characterized in various tissues and receptors have been identified. In the nervous system, sPLA2 groups IB, IIA, IIE, IIF, V, and XII have been identified, and binding sites for sPLA2 have been found. Here, we report sPLA2‐IIE and sPLA2‐X in rat brain as well as in neurons in primary culture. We furthermore confirm the presence of sPLA2‐V in rat brain and demonstrate the presence of sPLA2‐V in primary neuronal cultures. The distribution of sPLA2‐IIE, V, and ‐X seems to be mainly neuronal, with the highest abundance occurring in the cerebral cortex and hippocampus. We also find that sPLA2‐IIE, ‐V, and ‐X are differentially induced by kainic acid. This study supports the concept that sPLA2 heterogeneity in brain is functionally relevant and responsive to seizures. © 2006 Wiley‐Liss, Inc.
Role of Purα in targeting mRNA to sites of translation in hippocampal neuronal dendrites
Authors: Johnson Edward M. , Kinoshita Yayoi , Weinreb David B. , Wortman Margaret J. , Simon Ruth , Khalili Kamel , Winckler Bettina , Gordon Jennifer 
Published: March 2006

AbstractUsing genetic inactivation in the mouse, PURA, encoding Purα, is demonstrated to be essential for developmentally‐timed dendrite formation in the cerebellum and hippocampus. Comparison of RNA species bound by Purα prompts the hypothesis that Purα functions with non‐coding RNA in transport of certain mRNA molecules to sites of translation in dendrites. Purα binds to human BC200 RNA, implicated in dendritic targeting, and this has homologies to 7SL RNA, implicated in compartmentalized translation. Results using hippocampal rat neurons in situ show that Purα binds to BC1 RNA, implicated in dendritic targeting as a mouse counterpart of BC200, and to mRNA molecules translated in dendrites; Purα is specifically located in dendrites, where it is colocalized with Map2, but not in axons, where it fails to colocalize with Ankyrin G. Purα and Staufen are colocalized at dendritic sites of mRNA translation. Microtubule disruptors inhibit Purα dendritic targeting and allow its mislocalization to axons. Using mouse brain, double‐RNA immunoprecipitation places Purα together with Staufen or FMRP on BC1 RNA and specific mRNA species in vivo. These results help define a mechanism by which Purα targets specific mRNA molecules to sites of dendritic translation. © 2006 Wiley‐Liss, Inc.
Phosphorylated cAMP response element‐binding protein levels in guinea pig brainstem auditory nuclei after unilateral cochlear ablation
Authors: Mo Zhicheng , Suneja Sanoj K. , Potashner Steven J. 
Published: March 2006

AbstractAfter left unilateral cochlear ablation (UCA) in young adult guinea pigs, the appearance of plasticities in auditory pathways suggested altered gene expression and modified phenotypic behaviors of auditory neurons. Because phosphorylated cyclic‐AMP response element‐binding protein (CREB‐P) is a transcription factor that binds to certain genes to facilitate their expression, CREB‐P levels were measured after UCA and correlated with postablation plasticities. After UCA, Western blotting was employed to quantify CREB‐P levels and illustrate CREB levels in the anteroventral (AVCN), posteroventral (PVCN), and dorsal (DCN) cochlear nucleus; the lateral (LSO) and medial superior olive (MSO); the medial nucleus of the trapezoid body (MNTB); and the central nucleus of the inferior colliculus (ICc) for up to 145 days. We also quantified the levels of several protein synthesis regulators and synaptic markers in the AVCN at 60 days. Sucrose‐based extraction buffer improved CREB‐P recovery. CREB‐P levels became depressed at 3 and 7 postablation days, except in the PVCN, where they were elevated at 7 days, and in the ICc, where they were elevated at both times. At 60 days, CREB‐P levels in all the nuclei were elevated. In the AVCN, levels of the protein synthesis regulators and synaptic markers were also elevated at 60 days. By 145 days, CREB‐P levels again declined, except in the AVCN, where elevations persisted and increased on the ablated side, and in the ICc, where CREB‐P elevations remained. The changes in CREB‐P levels coincided with several plasticities in glutamatergic and glycinergic transmitter release and receptor activities, and alterations in neurotrophic support, that developed after UCA. These findings suggest that UCA altered CREB‐P levels, which in turn might have contributed to plasticities that appear after UCA. © 2006 Wiley‐Liss, Inc.
Characterization of chronic constriction of the saphenous nerve, a model of neuropathic pain in mice showing rapid molecular and electrophysiological changes
Authors: Walczak Jean‐Sébastien , Pichette Vincent , Leblond François , Desbiens Karine , Beaulieu Pierre 
Published: March 2006

AbstractNeuropathic pain is one of the most inextricable problems encountered in clinics, because few facts are known about its etiology. Nerve injury often leads to allodynia and hyperalgesia, which are symptoms of neuropathic pain. The aim of this study was to understand some molecular and electrophysiological mechanisms of neuropathic pain after chronic constriction of the saphenous nerve (CCS) in mice. After surgery, CCS mice displayed significant allodynia and hyperalgesia, which were sensitive to acute systemic injection of morphine (4 mg/kg), gabapentin (50 mg/kg), amitriptyline (10 mg/kg), and the cannabinoid agonist WIN 55,212‐2 (5 mg/kg). These behavioral changes were accompanied after surgery by an increase of c‐Fos expression and by an overexpression of μ‐opioid and cannabinoid CB1and CB2receptors in the spinal cord and the dorsal hind paw skin. In combination with the skin‐nerve preparation, this model showed a decrease in functional receptive fields downstream to the injury and the apparition of A‐fiber ectopic discharges. In conclusion, CCS injury induced behavioral, molecular, and electrophysiological rearrangements that might help us in better understanding the peripheral mechanisms of neuropathic pain. This model takes advantage of the possible use in the future of genetically modified mice and of an exclusively sensory nerve for a comprehensive study of peripheral mechanisms of neuropathic pain. © 2006 Wiley‐Liss, Inc.
Multidimensional liquid chromatography for sample characterisation
Authors: Toups E. Peter , Gray Michael J. , Dennis Gary R. , Reddy Narsimha , Wilson Michael A. , Shalliker R. Andrew 
Published: March 2006

AbstractWhile LC finds enormously widespread use in almost all areas of chemical science, the technique is limited as a means of identification because compounds do not elute with unique retention times. This limitation spurred the growth of hyphenated instrumental methods of analysis, such as LC–MS/MS, which because of the MS/MS detection became a method of identification. However, techniques like LC–MS/MS are specialised and require high initial purchase and running costs, inhibiting the more widespread growth of the technique. In an attempt to increase the separation power of LC, multi‐dimensional LC was developed. This expanded the separation space and subsequently has allowed the development of methods with fingerprinting ability due to the lower probability of component overlap. The work in this study illustrates the application of 2‐D LC as a means of chemical fingerprinting. We employed a sample base of various low molecular weight oligostyrenes and their diastereomers that represent a population of compounds whose selectivities in a one‐dimensional separation are almost unity and hence essentially impossible to separate. Yet in a 2‐D domain almost all individual components occupy unique 2‐D retention times.
Controlling LC–SPE–NMR systems
Authors: Wilson Steven Ray , Malerød Helle , Petersen Dirk , Simic Nebojsa , Bobu Maria‐Magdalena , Rise Frode , Lundanes Elsa , Greibrokk Tyge 
Published: March 2006

AbstractThere are several stages of the LC–SPE–NMR process that should be monitored closely to ensure an efficient isolation and concentration of the target analyte, for instance analyte break‐through and compound transfer from the LC–SPE to the NMR probe. In this study, analyte break‐through monitoring was performed with a UV detector and a mass spectrometer placed after the SPE unit. Easy break‐through was a problem when attempting multiple trapping of various compounds using C18 SPE cartridges with the original commercial system. However, on lowering the flow rate over the SPE system and using SPE cartridges packed with porous carbon, the number of trappings possible increased five‐fold. To increase control over the on‐line SPE–NMR transfer, a gradient pump‐UV system was used to elute compounds trapped on an SPE to an NMR probe. The analyte band was placed in the active volume of the probe by a stop‐flow mechanism. The modified LC–SPE system was also coupled with off‐line NMR analysis for determination of a degradation product of the insecticide monuron, present in the low ppm range.
Direct sensitive quantitative LC/MS analysis of C‐peptide from human urine by two dimensional reverse phase/reverse phase high‐performance liquid chromatography
Authors: Rogatsky Eduard , Tomuta Vlad , Cruikshank Greg , Vele Louis , Jayatillake Harsha , Stein Daniel 
Published: March 2006

AbstractWe describe for the first time the direct quantitative analysis of human C‐peptide from urine by isotope dilution assay. Implementation of 2‐D reverse phase‐reverse phase chromatography (2‐D RP‐RP) with SIM detection resulted in high assay sensitivity (LOQ = 5 pg on column), accuracy, and method ruggedness. Our experiments demonstrate the strong resolving capability of our proposed 2‐D RP‐RP platform which significantly reduces strong matrix effects and their resulting quantitation error over a wide range of urine concentrations. In contrast, single column methods (both SIM and multiple reaction monitoring) were found acceptable only for strongly diluted urine samples.