bluuebunny/crossref_metadata_2025_split huggingface dataset:
Michael Additions of Oxygen and Sulfur Nucleophiles to 3,4-Di-t-butyl-1-[(p-tolyl)sulfonylimino]-1,1-dihydrothiophene. A Comparison Study with 3,4-Di-t-butylthiophene 1-Oxide and 1,1-Dioxide
Authors: Otani Takashi , Sugihara Yoshiaki , Ishii Akihiko , Nakayama Juzo 
Published: November 2004

Abstract
The reactions of 3,4-di-t-butyl-1-[(p-tolyl)sulfonylimino]-1,1-dihydrothiophene with RONa and RSNa furnished 2-alkoxy- and 2-alkylthio-substituted thiophenes, respectively, through Michael adduct formation. The reaction of 3,4-di-t-butylthiophene 1-oxide with RSNa gave 1,6-Michael adducts, whereas the corresponding reaction of 3,4-di-t-butylthiophene 1,1-dioxide produced a mixture of 1,4- and 1,6-adducts.
New Chronoamperometric Technique Using Laser Ablation
Authors: Ohno Masashi , Hinoue Teruo 
Published: November 2004

Abstract
New chronoamperometry, in which a diffusion layer is renewed with laser ablation of an electrode surface, was compared with conventional potential step chronoamperometry. While the two methods gave similar current–time curves obeying the Cottrell equation for oxidation of hexacyanoferrate(II), only the new method gave the well-defined current–time curve for oxidation of ascorbic acid, which has a tendency to foul the electrode surface.
Low Threshold Gain-Narrowing Characteristics of Fluorescent Styrylbenzene Derivatives as a Guest Molecule in an Organic Thin-Film Optical Waveguide
Authors: Okumura Yasuaki , Nagawa Michifumi , Adachi Chihaya , Satsuki Makoto , Suga Sadaharu , Koyama Toshiki , Taniguchi Yoshio 
Published: November 2004

Abstract
We demonstrate that fluorescent styrylbenzene derivatives (SBDs) as a guest molecule (10 mol%) in an organic thin-film optical waveguide show excellent gain-narrowing performance by optical pumping. In particular, an extremely low threshold for gain narrowing is obtained with 4,4′-bis[4-(di-p-tolyl-amino)styryl]biphenyl (LD3). In addition, the incorporation of heterocyclic moieties into the styrylbenzene skeletons results in a higher threshold and also causes no spectral narrowing.
Photoinduced Intramolecular Hydrogen Atom Transfer of N-Salicylideneaniline in the Triplet State
Authors: Suzuki Toshihide , Kaneko Yuji , Arai Tatsuo 
Published: November 2004

Abstract
The excited triplet state of N-salicylideneanilines, benzylideneaniline derivatives, was successfully observed for the first time due to the intramolecular hydrogen bonding by means of transient absorption spectroscopy in solution. And the adiabatic intramolecular hydrogen atom transfer in the triplet state is proposed.
Preparation of Pd Cluster/Polymer Composites Using Bis(acetylacetonato)palladium(II) Vapor
Authors: Nakao Yukimichi 
Published: November 2004

Abstract
Composites consisting of Pd clusters and commodity polymers such as Nylon 6 and poly(ethylene terephthalate) are easily prepared by exposing the polymers to bis(acetylacetonate)palladium(II) vapor.
Hydrothermal Synthesis of a Novel Titanosilicate with MWW Topology
Authors: Wu Peng , Tatsumi Takashi , Komatsu Takayuki , Yashima Tatsuaki 
Published: November 2004

Abstract
A novel titanosilicate with the MWW topology hydrothermally synthesized in the presence of boron shows catalytic activity for the liquid-phase oxidation reaction of cyclohexene after removal of the extraframework Ti species by an acid treatment.
CO2-Encapsulated Clathrate Hydrate Formed by Sulfonate-Assisting Hydrogen Bonds and Template Contribution from Helper Species of Zinc(II)
Authors: Ichikawa Kazuhiko , Nakata Kou , Ibrahim M M 
Published: November 2004

Abstract
The CO2-encapsulated clathrate hydrate was formed, under a room temperature and atmosphere, by sulfonate-assisting hydrogen bonds among water molecules, where the geometry of the three sulfonate groups in zinc complex with nitrilotris(2-benzimidazolylmethyl-6-sulfonate) L1, was controlled by coordination of Zn2+.
The Formation of Quinolin-2(1H)-ones via Electrocyclic Reaction of o-Isocyanatostyrenes Generated in situ from o-Isocyanostyrenes
Authors: Kobayashi Kazuhiro , Kitamura Taichi , Yoneda Keiichi , Morikawa Osamu , Konishi Hisatoshi 
Published: November 2004

Abstract
A convenient one-pot preparation of 4-substituted or 3,4-disubstituted quinolin-2(1H)-ones from 2-isocyanostyrene derivatives, which involves mCPBA oxidation to the corresponding isocyanate intermediates followed by electrocyclization, is described.
Intramolecular Magnetic Interaction of Phenylene-Linked Bis-β-diketone Metal Complexes
Authors: Matsushita Michio M , Yasuda Tomohiro , Kawano Ryuji , Kawai Tadashi , Iyoda Tomokazu 
Published: November 2004

Abstract
Dinuclear metal complexes of phenylene-linked bis-β-di-ketone ligands were prepared and the magnetic interactions between the complex units along the &#960-conjugated linkers were investigated. Both ferro- and antiferromagnetic interactions were observed for the m- and p-phenylene-linked dimers, respectively.
A New Self-Assembled Porphyrin-Silver(I) Network
Authors: Kondo Mitsuru , Kimura Yu , Wada Kenji , Mizutani Tadashi , Ito Yoshikatsu , Kitagawa Susumu 
Published: November 2004

Abstract
A new self-assembled porphyrin compound, [Ag(H2TPyP)]·PF6 (H2TPyP = 5,10,15,20-tetrakis(4-pyridyl)porphyrin) (1), was synthesized and structurally characterized. Among four pyridyl groups of the H2TPyP molecule, the two groups in the trans positions are coordinated to the silver atom, resulting in the formation of a linear one-dimensional network, in which the other two pyridyl moieties remain metal-free. Each of the chain is associated by a weak π–π interaction to afford a slipped-stack structure.
Polishable Amperometric Hydrogen Peroxide Sensor Based on Sol-Gel-Derived Conductive Composite Containing Vanadium-17-molybdodiphosphate
Authors: Wang Peng , Wang Xiangping , Zhu Guoyi 
Published: November 2004

Abstract
A new kind of conductive vanadium-17-molybdodiphosphate/graphite/methylsilicate composite was firstly prepared by the sol-gel technique and used as electrode material for the fabrication of amperometric hydrogen peroxide sensor. The remarkable advantage of the sensor is its excellent reproducibility of surface renewal by simple mechanical polishing.
Monodispersed Microporous Polyoxotungstate with Regular Shape
Authors: Ito Takeru , Inumaru Kei , Misono Makoto 
Published: November 2004

Abstract
Monodispersed fine particles of (NH4)3PW12O40 having regular shape were successfully prepared as precipitates by the titration of NH4HCO3 solution to H3PW12O40 solution. The particles were ca. 1 µm in size and microporous with 151 m2 g−1 of BET surface area. AFM image demonstrated that these particles were aggregates of nanocrystallites of ca. 15 nm in size.
Synthesis of Energy Donors Appended Dithiaporphyrin Systems
Authors: Ravikanth M , Agarwal Neeraj , Kumaresan D 
Published: November 2004

Abstract
A dithiaporphyrin building block with N2S2 core is synthesized and used for the construction of N2S2 porphyrin appended with four N,N-difluoroboryl-1,9-dimethyl-5-(4-iodophenyl) dipyrrin (BDPY) units and N2S2 porphyrin appended with four N4 porphyrin units. Steady state fluorescence spectra indicated that there is no energy transfer from an excited BDPY unit to N2S2 porphyrin unit. However, an efficient energy transfer is observed from N4 porphyrin unit to N2S2 porphyrin unit.
Enhanced Catalytic Activity of Non-platinum Catalyst for Oxygen Reduction in Alkaline Solution
Authors: Sawai Keijiro , Suzuki Nobuhisa 
Published: November 2004

Abstract
Remarkable enhancement in catalytic activity of a non-platinum catalyst for oxygen reduction in alkaline solutions has been achieved by an oxidative pretreatment of a high-area carbon support before dispersion of catalyst precursor (cobalt hexacyanoferrate), followed by pyrolyzing the precursor under an inert atmosphere. The polarization potential for oxygen reduction at substantial current densities at room temperature under air was higher than a potential corresponding to a limit of relative predominance for O2/HO2− couple.
Photochemical and Enzymatic Synthesis of Methanol from HCO3− with Dehydrogenases and Zinc Porphyrin
Authors: Amao Yutaka , Watanabe Tomoe 
Published: November 2004

Abstract
Photochemical and enzymatic methanol synthesis from HCO3− with formate dehydrogenase (FDH), aldehyde dehydrogenase (AldDH), and alcohol dehydrogenase (ADH) via the photoreduction of MV2+ using ZnTPPS photosensitization was developed and the amount of produced methanol was 0.55 μmol dm−3 after 4-h irradiation.
Gene Detection Based on the Tetrakis-acridinyl Peptide (TAP) Cassette
Authors: Mizuki Keiji , Nojima Takahiko , Takenaka Shigeori 
Published: November 2004

Abstract
The TAP cassette, formed by the reaction of TAP with a DNA probe carrying a continuous AT sequence, was used for the detection of target DNA by the sandwich assay on the titer plate. This was achieved by the characteristics of TAP having high affinity and high preference for double stranded DNA and dramatic enhancement of fluorescence of TAP bound to [poly(dA-dT)]2.
The Hydrogen Salicylate Ion as Ligand. Complex Formation Equilibria with Dioxouranium(VI), Neodymium(III) and Lead(II)
Authors: Furia Emilia , Porto Raffaella 
Published: November 2004

AbstractThe complexation equilibria of the hydrogen salicylate ion, HL‐, have been studied, at 25 °C, by potentiometric measurements with a glass electrode in 1 M NaClO4 for uranyl and Nd(III) ions and in 3 M NaClO4 for Pb(II) ion. The ligand concentration (CL) was varied between 10‐3 and 0.05 M. In the system with U(VI) the concentrations ranged between: 10‐3 ≤ [U(VI)] ≤ 0.01 M, 0.5 ≤ CL /[U(VI)] ≤ 10 and 10‐2 d[H+]≤ 10‐5 M; for neodymium system: 2.10‐3 ≤ [Nd(III)] < 0.01, 1 ≤ CL /[Nd(III)] ≤ 10 and 10‐2 ≤ [H+] ≤ 10‐7 M; for lead system: 10‐3 ≤ [Pb(II)] ≤ 3.10‐3, 1 ≤ CL /[Pb(II)] ≤ 2 and 10‐5 ≤ [H+] ≤ 10‐7.3 M. The experimental data have been explained with the formation of UO2HL+, UO2L, UO2(OH)L , (UO2)2(OH)L2 UO2(HL)L , NdHL2+, NdL+, Nd(OH)L, PbHL+, PbL and PbL22—. Equilibrium infinite dilution.
Screening of Urban Aerosol Particulate Composites for Selected Metal Distribution and Their Dependence on Meteorological Parameters
Authors: Shah Munir H. , Shaheen Nazia , Jaffar M. 
Published: November 2004

AbstractLocal atmospheric aerosol particulate samples, collected as composites on daily 6‐12 hour basis, at Quaid‐i‐Azam University campus, Islamabad, Pakistan, using high volume sampling technique, were analysed for Pb, Na, K, Fe, Mn, Cd, Cr, Ni, Zn and Co by FAAS method. The monitoring period ran from October, 2001 through March, 2002, with a total of 105 samples collected on cellulose filters, treated in part with the HNO3‐based wet digestion method for metal quantification, and for particle size distribution separately. The metal content of the aerosols was examined in relation to dependence on meteorological parameters, such as temperature, relative humidity, wind speed, sun shine and pan evaporation. Statistical correlation analysis was conducted for multiple metal pairs in aerosols, and the data were examined in relation to meteorological parameters and relevant aerosol particle size fractions. The study revealed no viable strong correlation between the meteorological parameters and metal levels; in general, however, a significant positive correlation was found for temperature. A strong positive correlation was observed for PM<2.5 and PM2.5‐10. For coarse particles (PM10‐100 and PM>100), however, a negative correlation was observed. The levels of Na, K, Fe and Zn were found in the range of 1‐5 μg/m3 while those for the rest of the metals in the sub μg/m3 range. Principal component analysis and cluster analysis were performed on dataset for source identification and appointment. Largest contribution (33%) was shown by the industrial emissions followed by traffic/road dust (16.7%).
The Acidity Constants of Some Pyrimidine Bases in Various Water Organic Solvent Media
Authors: Ahmed Iman T. , Soliman Ekram S. , Boraei Ahmed A. A. 
Published: November 2004

AbstractThe acid ionization constants of some pyrimidine bases of nucleic acids were determined pH‐metrically at 25 °C and at the constant ionic strength I = 0.10 mol l‐1 (KNO3) in pure water as well as in aqueous media containing variable mole percentages (5—30 %) of organic solvents. The organic solvents used were methanol, ethanol, N, N‐dimethylformamide (DMF), dimethylsulfoxide (DMSO), acetonitrile, acetone and dioxane. The results obtained indicated that the acidity constants are generally decreased as the content of an organic solvent in the medium is increased. It was deduced that the hydrogen bonding interactions and the solvent basicity in addition to the electrostatic effect are the major effects influencing significantly the acid ionization process of pyrimidine bases in the different water organic solvent media. Some thermodynamic parameters (ΔH, ΔG°, ΔS°) of the ionization process over the temperature range 5—45°C in pure water were also determined and discussed.
Browsing image collections with representations of common‐sense activities
Authors: Gordon Andrew S. 
Published: November 2004

AbstractTo support browsing‐based subject access to image collections, it is necessary to provide users with networks of subject terms that are organized in an intuitive, richly interconnected manner. A principled approach to this task is to organize the subject terms by their relationship to activity contexts that are commonly understood among users. This article describes a methodology for creating networks of subject terms by manually representing a large number of common‐sense activities that are broadly related to image subject terms. The application of this methodology to the Library of Congress Thesaurus for Graphic Materials produced 768 representations that supported users of a prototype browsing‐based retrieval system in searching large, indexed photograph collections.
Structured natural‐language descriptions for semantic content retrieval of visual materials
Authors: Tam A. M. , Leung C. H. C. 
Published: November 2004

AbstractKeyword search of multimedia collections lacks precision and automatic parsing of unrestricted natural language annotations lacks accuracy. We propose a structure for natural language descriptions of the semantic content of visual materials that requires descriptions to be (modified) keywords, phrases, or simple sentences, with components that are grammatical relations common to many languages. This structure makes it easy to implement a collection's descriptions as a relational database, enabling efficient search via the application of well‐developed database‐indexing methods. Description components may be elements from external resources (thesaurus, ontology, database, or knowledge base). This provides a rich superstructure for the meaningful retrieval of images by their semantic contents.
A conceptual framework and empirical research for classifying visual descriptors
Authors: Jörgensen Corinne , Jaimes Alejandro , Benitez Ana B. , Chang Shih‐Fu 
Published: November 2004

AbstractThis article presents exploratory research evaluating a conceptual structure for the description of visual content of images. The structure, which was developed from empirical research in several fields (e.g., Computer Science, Psychology, Information Studies, etc.), classifies visual attributes into a “Pyramid” containing four syntactic levels (type/technique, global distribution, local structure, composition), and six semantic levels (generic, specific, and abstract levels of both object and scene, respectively). Various experiments are presented, which address the Pyramid's ability to achieve several tasks: (1) classification of terms describing image attributes generated in a formal and an informal description task, (2) classification of terms that result from a structured approach to indexing, and (3) guidance in the indexing process. Several descriptions, generated by naive users and indexers, are used in experiments that include two image collections: a random Web sample, and a set of news images. To test descriptions generated in a structured setting, an Image Indexing Template (developed independently over several years of this project by one of the authors) was also used. The experiments performed suggest that the Pyramid is conceptually robust (i.e., can accommodate a full range of attributes), and that it can be used to organize visual content for retrieval, to guide the indexing process, and to classify descriptions obtained manually and automatically.
The role of individual differences in Internet searching: An empirical study
Authors: Ford Nigel , Miller David , Moss Nicola 
Published: November 2004

AbstractThis article reports the results of a study of the role of individual differences in Internet searching. The dimensions of individual differences forming the focus of the research consisted of: cognitive styles; levels of prior experience; Internet perceptions; study approaches; age; and gender. Sixty‐nine Masters students searched for information on a prescribed topic using the AltaVista search engine. Results were assessed using simple binary relevance judgements. Factor analysis and multiple regression revealed interesting differences, retrieval effectiveness being linked to: male gender; low cognitive complexity; an imager (as opposed to verbalizer) cognitive style; and a number of Internet perceptions and study approaches grouped here as indicating low self‐efficacy. The implications of these findings for system development and for future research are discussed.
A quantitative categorical analysis of metadata elements in image‐applicable metadata schemas
Authors: Greenberg Jane 
Published: November 2004

AbstractThis article reports on a quantitative categorical analysis of metadata elements in the Dublin Core, VRA Core, REACH, and EAD metadata schemas, all of which can be used for organizing and describing images. The study found that each of the examined metadata schemas contains elements that support the discovery, use, authentication, and administration of images, and that the number and proportion of elements supporting functions in these classes varies per schema. The study introduces a new schema comparison methodology and explores the development of a class‐oriented functional metadata schema for controlling images across multiple domains.
Radioisotope bone scans in the preoperative staging of hepatopancreatobiliary cancer
Authors: Sheth H , Javed S S , Hilson A J W , Buscombe J R , Davidson B R 
Published: November 2004

Abstract

Background
The aim of the study was to determine the value of radioisotope bone scans in the preoperative staging of patients with hepatopancreatobiliary (HPB) cancer.

Methods
Bone scanning was performed as part of a routine staging protocol in 402 consecutive patients with HPB cancer over a period of 5 years. Patients with positive bone scans underwent coned radiography, computed tomography with review on bone windows, or a bone biopsy. Bone scans were reviewed along with staging investigations, surgical and histological findings. Patients were followed for a minimum of 6 months.

Results
There were 171 patients with colorectal liver metastases, 106 with suspected pancreatic cancer, 47 with hepatocellular cancer, 52 with gallbladder cancer or cholangiocarcinoma, and 26 with other types of HPB cancer. Bone scans were negative in 377 patients (93·8 per cent) and positive in 25 patients (6·2 per cent). Of the 25 positive scans, 16 were falsely positive as a result of degenerative bone disease. Of nine patients with a true-positive bone scan, four had locally irresectable disease and four distant metastases. In only one patient did the bone scan result alone influence the decision to resect the HPB cancer. Overall sensitivity was 100 per cent, specificity 95·9 per cent, positive predictive value 36·0 per cent and negative predictive value 100 per cent.

Conclusion
Bone scanning should not be included in the routine staging protocol for HPB cancer.
DARPP‐32‐like immunoreactivity in AII amacrine cells of rat retina
Authors: Partida Gloria J. , Lee Sherwin C. , Haft‐Candell Leah , Nichols Grant S. , Ishida Andrew T. 
Published: November 2004

AbstractPrevious studies demonstrated that the dopamine‐ and adenosine 3′,5′‐monophosphate‐regulated phosphatase inhibitor known as “DARPP‐32” is present in rat, cat, monkey, and human retinas. We have followed up these studies by asking what specific cell subtypes contain DARPP‐32. Using a polyclonal antibody directed against a peptide sequence of human DARPP‐32, we immunostained adult rat retinas that were either transretinally sectioned or flat mounted and found DARPP‐32‐like immunoreactivity in some cells of the amacrine cell layer across the entire retinal surface. We report here, based on the shape and spatial distribution of these cells, their staining by an anti‐parvalbumin antibody, and their juxtaposition with processes containing tyrosine hydroxylase, that DARPP‐32‐like immunoreactivity is present in AII amacrine cells of rat retina. These results suggest that the response of AII amacrine cells to dopamine is not mediated as simply as previously supposed. J. Comp. Neurol. 480:251–263, 2004. © 2004 Wiley‐Liss, Inc.
Septal columns in rodent barrel cortex: Functional circuits for modulating whisking behavior
Authors: Alloway Kevin D. , Zhang Mengliang , Chakrabarti Shubhodeep 
Published: November 2004

AbstractIn rodents, each mystacial whisker is represented in the granular layer of primary somatosensory (SI) cortex by a compact cluster of cells known as a barrel, and barrels are separated from each other by domains that are called septa. Vertical columns of neurons aligned with each barrel act as a functional assembly to process information from a “principal” whisker, but a functional role has not been identified for vertical columns of neurons that are aligned with the septa. To determine whether these septal columns provide the main source of projections to primary motor (MI) cortex, we placed retrograde tracers in MI cortex and analyzed the location of the retrogradely labeled neurons with respect to the septal and barrel compartments of SI barrel cortex. In cases in which SI barrel cortex was sectioned tangentially, retrogradely labeled neurons in the extragranular layers of SI were plotted and superimposed onto reconstructions of the layer IV barrel field. In each of these cases, most labeled neurons were located above or below the septal regions of layer IV. When SI barrel cortex was sectioned coronally, we observed multiple columns of labeled SI neurons that were vertically aligned with the septal zones of layer IV. These results indicate that columns of neurons that are vertically aligned with the septa, or septal columns, are functionally linked by virtue of their projections to MI cortex. We hypothesize that these septal columns represent an interconnected and functionally distinct circuit that transmits information to MI and other brain regions involved in motor control. J. Comp. Neurol. 480:299–309, 2004. © 2004 Wiley‐Liss, Inc.