bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nitration of Alkanes with Nitric Acid by Vanadium‐Substituted Polyoxometalates
Authors: Shinachi Satoshi , Yahiro Hidenori , Yamaguchi Kazuya , Mizuno Noritaka 
Published: November 2004

AbstractThe nitration of alkanes by using nitric acid as a nitrating agent in acetic acid was efficiently promoted by vanadium‐substituted Keggin‐type phosphomolybdates such as [H4PVMo11O40], [H5PV2Mo10O40], and [H6PV3Mo9O40] as catalyst precursors. A variety of alkanes including alkylbenzenes were nitrated to the corresponding nitroalkanes as major products in moderate yields with formation of oxygenated products under mild reaction conditions. The carboncarbon bond cleavage reactions hardly proceeded. ESR, NMR, and IR spectroscopic data show that the vanadium‐substituted polyoxometalate, for example, [H4PVMo11O40], decomposes to form free vanadium species and [PMo12O40]3− Keggin anion. The reaction mechanism involving a radical‐chain path is proposed. The polyoxometalates initially abstract the hydrogen of the alkane to form the alkyl radical and the reduced polyoxometalates. The reduced polyoxometalates subsequently react with nitric acid to produce the oxidized form and nitrogen dioxide. This step would be promoted mainly by the phosphomolybdates, [PMo12O40]n−, and the vanadium cations efficiently enhance the activity. The nitrogen dioxide promotes the further formation of nitrogen dioxide and an alkyl radical. The alkyl radical is trapped by nitrogen dioxide to form the corresponding nitroalkane.
Convergent Synthesis of Platinum–Acetylide Dendrimers
Authors: Onitsuka Kiyotaka , Fujimoto Masanori , Kitajima Hotaka , Ohshiro Nobuaki , Takei Fumie , Takahashi Shigetoshi 
Published: November 2004

AbstractAn efficient convergent route to the main chain type of organometallic dendrimers, in which platinum moieties are linked by 1,3,5‐triethynylbenzene, has been developed. The synthesis of platinum–acetylide dendrons involved the use of two types of trialkylsilyl groups for protection of the terminal acetylene. The platinum–acetylide dendrimers were prepared up to the third generation by reacting dendrons with a triplatinum core and a tetraplatinum core. Spectroscopic characterization and trace experiments by gel permeation chromatography indicated that the dendrimer molecules have no structural defects. Although a π‐conjugated system was used as the bridging ligand, electronic and fluorescence spectra suggested that the interaction among the platinum–acetylide moieties in the dendrimers was small.
Chiral Molecular Glass: Synthesis and Characterization of Enantiomerically Pure Thiophene‐Based [7]Helicene
Authors: Miyasaka Makoto , Rajca Andrzej , Pink Maren , Rajca Suchada 
Published: November 2004

AbstractSynthesis of thiophene‐based [7]helicenes, which are functionalized for both design of organic chiral glasses with strong chiroptical properties and for further homologation to higher [n]helicenes, is reported. The key synthetic transformations are kinetic resolution of the intermediate diketone and the annelation step forming the center benzene ring by means of an intramolecular McMurry reaction. Based upon X‐ray crystallographic determinations of the absolute configurations for (+)‐enantiomers of the diketone and the [7]helicene, stereochemical correlation between the (R) axial chirality of the diketone and the (M) helical chirality of the [7]helicene is established. One such enantiopure trimethylsilyl‐substituted [7]helicene possesses enchanced chiroptical properties and forms a chiral molecular glass.
Titanium(IV) and Zirconium(IV) Sulfato Complexes Containing the Kläui Tripodal Ligand: Molecular Models of Sulfated Metal Oxide Surfaces
Authors: Zhang Qian‐Feng , Lam Tony C. H. , Yi Xiao‐Yi , Chan Eddie Y. Y. , Wong Wai‐Yeung , Sung Herman H. Y. , Williams Ian D. , Leung Wa‐Hung 
Published: November 2004

AbstractTreatment of titanyl sulfate in about 60 mM sulfuric acid with NaLOEt (LOEt−=[(η5‐C5H5)Co{P(O)(OEt)2}3]−) afforded the μ‐sulfato complex [(LOEtTi)2(μ‐O)2(μ‐SO4)] (2). In more concentrated sulfuric acid (>1 M), the same reaction yielded the di‐μ‐sulfato complex [(LOEtTi)2(μ‐O)(μ‐SO4)2] (3). Reaction of 2 with HOTf (OTf=triflate, CF3SO3) gave the tris(triflato) complex [LOEtTi(OTf)3] (4), whereas treatment of 2 with Ag(OTf) in CH2Cl2 afforded the sulfato‐capped trinuclear complex [{(LOEt)3Ti3(μ‐O)3}(μ3‐SO4){Ag(OTf)}][OTf] (5), in which the Ag(OTf) moiety binds to a μ‐oxo group in the Ti3(μ‐O)3 core. Reaction of 2 in H2O with Ba(NO3)2 afforded the tetranuclear complex (LOEt)4Ti4(μ‐O)6 (6). Treatment of 2 with [{Rh(cod)Cl}2] (cod=1,5‐cyclooctadiene), [Re(CO)5Cl], and [Ru(tBu2bpy)(PPh3)2Cl2] (tBu2bpy=4,4′‐di‐tert‐butyl‐2,2′‐dipyridyl) in the presence of Ag(OTf) afforded the heterometallic complexes [(LOEt)2Ti2(O)2(SO4){Rh(cod)}2][OTf]2 (7), [(LOEt)2Ti(O)2(SO4){Re(CO)3}][OTf] (8), and [{(LOEt)2Ti2(μ‐O)}(μ3‐SO4)(μ‐O)2{Ru(PPh3)(tBu2bpy)}][OTf]2 (9), respectively. Complex 9 is paramagnetic with a measured magnetic moment of about 2.4 μB. Treatment of zirconyl nitrate with NaLOEt in 3.5 M sulfuric acid afforded [(LOEt)2Zr(NO3)][LOEtZr(SO4)(NO3)] (10). Reaction of ZrCl4 in 1.8 M sulfuric acid with NaLOEt in the presence Na2SO4 gave the μ‐sulfato‐bridged complex [LOEtZr(SO4)(H2O)]2(μ‐SO4) (11). Treatment of 11 with triflic acid afforded [(LOEt)2Zr][OTf]2 (12), whereas reaction of 11 with Ag(OTf) afforded a mixture of 12 and trinuclear [{LOEtZr(SO4)(H2O)}3(μ3‐SO4)][OTf] (13). The ZrIV triflato complex [LOEtZr(OTf)3] (14) was prepared by reaction of LOEtZrF3 with Me3SiOTf. Complexes 4 and 14 can catalyze the Diels–Alder reaction of 1,3‐cyclohexadiene with acrolein in good selectivity. Complexes 2–5, 9–11, and 13 have been characterized by X‐ray crystallography.
Fine‐needle aspiration of primary and recurrent benign fibrous histiocytoma: Classic, aneurysmal, and myxoid variants
Authors: Klijanienko Jerzy , Caillaud Jean‐Michel , Lagacé Réal 
Published: November 2004

AbstractThere is a limited number of correlative cytopathological studies of fibrous histiocytoma (FHC). To better define cytopathological criteria of diagnosis, we have reviewed fine‐needle aspirates (FNA) from 36 FHCs (32 classical, 1 myxoid, and 3 aneurysmal variants on corresponding histological sections).Original cytological diagnoses were benign in 33 (91.7%) cases (22 accurate) and false positive in 3 (8.3%) cases. All smears were surprisingly homogenous and composed of histiocytic cells with finely vacuolated cytoplasm in 27 (75%) cases, small regular spindle cells in 25 (69%) cases, and giant cells in 17 (47%) cases. Histiocytic cells were attached to vascular structures in 9 (25%) cases. Slight cytonuclear atypia was seen in five (14%) cases. Three (8.3%) cases showed numerous siderophages. In two (5.6%) cases, there were abundant inflammatory backgrounds and in one (3%) case there was a scant myxoid background. Storiform patterns, round cells, prominent atypia, necroses, or mitotic figures were not seen.FHC should be differentiated from other benign, low‐ and intermediate‐grade spindle‐cell neoplasms such as low‐grade fibrosarcoma, dermatofibrosarcoma protuberans, nodular fasciitis, spindle‐cell malignant melanoma, and monophasic synovial sarcoma. Some cases may be misinterpreted as malignant, especially in cases of recurrence or in patients with a cancer history. Diagn. Cytopathol. 2004;31:387–391. © 2004 Wiley‐Liss, Inc.
A target detection algorithm using polarimetric notch filter
Authors: Suwa Kei , Yamamoto Kazuhiko , Nonaka Chikafusa , Imamura Akihito , Kirimoto Tetsuo 
Published: November 2004

AbstractWhen vehicles and ships are observed by radar, echoes from the target are buried in the echoes (clutter) from the ground and the sea surface in the background and detection becomes difficult. Previously, a method known as a Polarimetric Whitening Filter (PWF) was proposed as a target detection technique that focuses on the difference in the polarizations of the clutter and the target and verified its effectiveness. In addition, the authors proposed the Polarimetric Notch Filter (PNF) as a clutter suppression scheme in an environment with a low signal‐to‐clutter power ratio (SCR) and verified the achievement of superior improvement in the SCR performance. In this paper, we propose a target detection algorithm that obtains a constant probability of false alarm by whitening the polarization characteristic of the residual clutter power after suppressing the clutter power by the PNF. From the results of evaluations by computer simulation, we see that the SCR improvement factor of the proposed method was on average about 1.5 dB better than conventional PWF, but the target detection probability was nearly identical. In addition, the results of the performance evaluation of the polarization data of the noise of asphalt and vehicles acquired by polarimetric FMCW radar in the 95‐GHz band where the SCR improvement factors of PNF and PWF were 7.44 and 5.85 dB, respectively, and the SCR improvement factor of PNF was 1.59 dB better. Although the target detection probability was somewhat higher for PNF than PWF, they were nearly identical. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 88(3): 33–43, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20158
Ideological beliefs as determinants of discrimination in positive and negative outcome distributions
Authors: Amiot Catherine E. , Bourhis Richard Y. 
Published: November 2004

AbstractSocial identity theory proposes that discrimination contributes favourably to group members' social identity. In minimal group paradigm (MGP) studies involving positive outcome distributions (e.g. money), discrimination is associated with a more positive social identity. But studies on the positive‐negative asymmetry effect show that categorization leads to less discrimination when negative (salary cuts) than when positive outcomes (salary increases) are distributed. Using structural equation modelling, this study (N = 279) tested whether discrimination involving negative outcome distributions could contribute as much to group members' positive social identity as discrimination on positive outcomes. The study also tested if ideological beliefs (i.e. social dominance orientation, authoritarianism), measured one month before the MGP experiment, could predict positive and negative outcome discrimination. While the fit of the hypothesized model was adequate, only social dominance orientation predicted both positive and negative outcome discrimination. Also, discrimination on positive outcomes but not on negative ones contributed to positive social identity. Copyright © 2004 John Wiley & Sons, Ltd.
Genetic polymorphism of drug‐metabolizing enzymes and styrene‐induced DNA damage
Authors: Buschini Annamaria , De Palma Giuseppe , Poli Paola , Martino Anna , Rossi Carlo , Mozzoni Paola , Scotti Eleonora , Buzio Luca , Bergamaschi Enrico , Mutti Antonio 
Published: November 2004

AbstractA cross‐sectional study was carried out on 48 workers exposed to styrene and 14 unexposed healthy controls in order to investigate the genotoxic potential of styrene exposure. DNA damage was assessed in peripheral blood leukocytes (WBCs) by the comet assay. Polymorphisms in glutathione S‐transferase genes (GSTM1, GSTT1, GSTP1) and the gene encoding microsomal epoxide hydrolase (EPHX) were characterized to assess their possible modifying role in styrene metabolism and subsequent DNA damage. Exposed workers showed significantly higher levels of DNA damage compared to controls. Among workers, the GSTM1 and GSTT1 polymorphisms significantly affected comet parameters. Subjects bearing a GSTM1pos genotype showed a significantly higher proportion of damaged nuclei compared to people lacking GSTM1‐1 expression (GSTM1null), whereas GSTT1pos workers showed significantly lower DNA damage than GSTT1null individuals. Styrene‐7,8‐oxide (SO)‐induced DNA damage was assessed in vitro in WBCs isolated from the healthy controls. A clear dose–response relationship at micromolar doses of SO was found for the whole group. WBCs collected from subjects bearing the homozygous wildtype GSTP1 genotype showed a significant protection compared to cells from subjects bearing at least one GSTP1 variant allele. The field survey confirms that styrene exposure is associated with increased DNA damage and indicates a modulating role for GSTM1 and GSTT1 genotypes. In vitro experiments suggest that the extent of SO‐induced DNA strand breaks depends, at least in part, on interindividual differences in GSH‐conjugation capabilities. Environ. Mol. Mutagen. 41:243–252, 2003. © 2003 Wiley‐Liss, Inc.
Detection of ghost cells in the standard alkaline comet assay is not a good measure of apoptosis
Authors: Meintières Sophie , Nesslany Fabrice , Pallardy Marc , Marzin Daniel 
Published: November 2004

AbstractThe single cell gel electrophoresis assay, or Comet assay, is a powerful tool for measurement of DNA strands breaks, oxidative damage, and alkali labile sites, and the assay was recently modified to detect DNA cross‐links. It has also been proposed as a measure of apoptosis since apoptotic cells are suspected to result in total migration of the DNA from the nucleus into the tail. Cells with this appearance are called ghost cells, clouds, hedgehogs, or NDCN (nondetectable cell nuclei). The aim of this study was to determine if ghost cells can be used to measure apoptosis in the standard alkaline comet assay. To answer this question, we made use of two cell lines: CTLL‐2 cells that can enter apoptosis upon addition of apoptosis stimuli or IL‐2 deprivation, and CTLL‐2 bcl2 cells that are protected from apoptosis due to the overexpression of the apoptosis inhibitor gene bcl2. The two cell lines were treated with cytotoxins (nongenotoxic apoptosis inducers, nongenotoxic necrotic agents) or genotoxins. They were also subjected to growth factor withdrawal, which induced apoptosis in the CTLL‐2 cell line. The level of apoptosis was measured by the Annexin V‐FITC method in parallel with performing the Comet assay. The results obtained in the two cell lines suggest that apoptotic or necrotic death does not correlate well with the detection of ghost cells, presumably because these cells are lost upon electrophoresis. A variant of the alkaline Comet assay that was performed without electrophoresis (halo method) was able to efficiently detect cells undergoing apoptosis, but it was unable to clearly distinguish between apoptosis and genotoxic damage. Environ. Mol. Mutagen. 41:260–269, 2003. © 2003 Wiley‐Liss, Inc.
Fine mapping of chromosome 10q deletions in mycosis fungoides and sezary syndrome: Identification of two discrete regions of deletion at 10q23.33–24.1 and 10q24.33–25.1
Authors: Wain E. Mary , Mitchell Tracey J. , Russell‐Jones Robin , Whittaker Sean J. 
Published: November 2004

AbstractPrevious cytogenetic studies in mycosis fungoides (MF) and Sezary syndrome (SS) have identified a large and poorly defined area of chromosomal deletion on chromosome 10q. We report an extensive fine‐mapping allelotyping study using 19 microsatellite markers in the region 10q22.3–10q26.13. Allelic loss was identified by loss of heterozygosity analysis in 26 of 60 (43%) cases: 15 of 45 (33%) with MF and 11 of 15 (73%) with SS. MF and SS samples showed similar patterns of allelic loss with the identification of two discrete regions of deletion which were mutually exclusive in all but two cases. Within the first region of deletion at 10q23.33–10q24.1, around microsatellite marker D10S185 (2.77 Mb), 23 genes were identified, including three (KIF11, HHEX, and HELLS) with functions that, if dysregulated, could be critical in MF and SS. The second region of deletion, 10q24.33–10q25.1, around microsatellite marker D10S530 (3.92 Mb), encodes 11 genes, the majority of which have poorly identified functions. This extensive allelotyping study provides the basis for future highly selective candidate gene analyses. © 2004 Wiley‐Liss, Inc.
Participatory management: Would it be a turning point in the history of the Gezira scheme?
Authors: Abdelhadi A. W. , Adam H. S. , Hassan Mohamed A. , Hata Takeshi 
Published: November 2004

AbstractSince its establishment in 1925 decisions in the Sudan's Gezira irrigated scheme have been top‐down from the central headquarters of the Sudan Gezira Board (SGB). The irrigation system is divided into the upper system (US) that includes the dam, main, branch and major canals and the lower system that comprises the minor, tertiary and field channels. The Ministry of Irrigation and Water Resources (MOIWR) is responsible for the O&M of the US in addition to the maintenance of the Minor canals. The operation of the minor canals is handled by the SGB. The maintenance of the minor canals was given to the SGB in 1999, thus unifying O&M for the first time in 75 years. This opened the door for the O&M to be handed to tenants in a pilot project (PP) supported by the FAO during 2000–2002. Crop yields in the PP outyielded the neighboring blocks as well as the scheme average during the two years of the project. The PP is to be extended to at least one block in each of the 18 Gezira administrative groups. The PP established the base of legalization and institutional arrangements that govern the water users' activities and resulted in a great change in tenants' attitudes towards water management. Copyright © 2004 John Wiley & Sons, Ltd.
Field measurement and simulation of advance rates for continuous and surge irrigated furrows in Pakistan
Authors: Latif Muhammad , Mahmood Sajid 
Published: November 2004

AbstractField tests were conducted with inflow rates of 1.7–2.4 l s−1 to compare the advance rates both in continuous and surge‐irrigated furrows. The furrows were 149 m long, with 0.2–1.5% slopes. Water applied and rate of water advance were measured during five irrigation events. During the first irrigation, a reduction in applied water volume of 23–60% was observed in surge‐irrigated furrows compared with continuous irrigation. It was further noted during the course of the experiments that the surging effect was more pronounced during the first irrigation than in the subsequent irrigation events. However, it was noted that there would be hardly any benefit of the surge for smaller field lengths of 61 m, which are commonly used in Pakistan and many other developing countries. Results simulated by the SIRMOD model revealed that the water front advance curves matched closely with the observed ones in most surge treatments. The simulated performance efficiencies encourage the use and adaptation of surge irrigation in Pakistan, but more field studies are needed for its verification and for making concrete recommendations for its use in farmers' fields. Copyright © 2004 John Wiley & Sons, Ltd.
A water budget technique for the design of open drainage systems
Authors: Panda Rabindra Kumar , Rajput T. B. S. 
Published: November 2004

AbstractA computer‐based water budget technique was developed considering the land gradient [{vertical interval between two adjacent field bunds (levees)=20 cm} ÷ the distance between the bunds] and paddy field bunds (viz. 16, 18, 20, 22, 24 cm) in its formulation for computing daily runoff from coastal paddy areas in India. The inputs used in the water budget technique consist of limited meteorological data that are easily available in India. The water budget technique was validated with the modified curve number method and the measured data collected during 2001 in a coastal paddy area of Orissa (east coast of India close to Bay of Bengal), India and its superiority was found. In most of the cases (barring a few events of 16 cm and 18 cm paddy field bunds for the water budget technique), statistically both methods differed significantly from each other while generating daily runoff. The estimate of the surface drainage coefficient (the amount of excess surface runoff water to be drained from the crop field during a 24‐hour period) for a 5‐year return period was computed as 100 mm day−1 (taking the 22 cm paddy field bund) and 109 mm day−1 in case of the water budget technique and modified curve number method, respectively. Copyright © 2004 John Wiley & Sons, Ltd.
Improved gene transfer and normalized enzyme levels in primitive hematopoietic progenitors from patients with mucopolysaccharidosis type I using a bioreactor
Authors: Pan Dao , Stroncek David F. , Whitley Chester B. 
Published: November 2004

AbstractBackgroundOne of the major barriers to the clinical application of hematopoietic stem cell (HSC) gene therapy has been relatively low gene transfer efficiency. Other inadequacies of current transduction protocols are related to their multi‐step procedures, e.g., using tissue‐culture flasks, roller bottles or gas‐permeable bags for clinical application.MethodsIn comparison with a conventional bag transduction protocol, a ‘closed’ hollow‐fiber bioreactor system (HBS) was exploited to culture and transduce human peripheral blood CD34+ progenitor cells (PBPCMPS) from patients with mucopolysaccharidosis type I (MPS I) using an amphotropic retroviral vector based on a murine Moloney leukemia virus LN prototype. Both short‐term colony‐forming cell (CFC) and long‐term culture initiating cell (LTCIC) assays were employed to determine transduction frequency and transgene expression in committed progenitor cells and primitive progenitors with multi‐lineage potentials.ResultsA novel ultrafiltration‐transduction method was established to culture and transduce enzyme‐deficient PBPCMPS over a 5‐day period without loss in viability and CD34 identity (n = 5). Significantly higher transduction efficiencies were achieved in primary CFC that derived from the HBS (5.8–14.2%) in comparison with those from gas‐permeable bags (undetectable to 1.7%; p < 0.01). Up to 15‐fold higher‐than‐normal enzyme activity was found in selected PBPCMPS‐LP1CD transductants. Moreover, higher gene transfer (4.4‐fold) and expression in very primitive progenitors were observed in products from the HBS compared with bag experiments as indicated by CFC derived from primitive LTCIC. Remarkably, with relatively modest gene transfer levels in LTCIC from HBS experiments, the expression of the IDUA transgene corrected the enzyme‐deficiency in 5‐week long‐term cultures (LTC).ConclusionsMPS I progenitor cells achieved normalized enzyme levels in LTC after transduction in a HBS system. These studies demonstrate the advantages of a bioreactor‐transduction system for viral‐mediated stem cell gene transfer. Copyright © 2004 John Wiley & Sons, Ltd.
Improved high‐performance liquid chromatographic determination of guanidino compounds by pre‐column dervatization with ninhydrin and fluorescence detection
Authors: Buchberger Wolfgang , Ferdig Matthias 
Published: November 2004

AbstractNinhydrin has been investigated as a pre‐column derivatization reagent for guanidino compounds. The reaction takes place under strongly alkaline conditions, followed by a second step at low pH and elevated temperature. This procedure yields derivatives with favourable fluorescence properties (excitation at 390 nm, emission at 470 nm). Amino acids do not react with ninhydrin under these conditions so that the method can easily be used for biological samples. Reversed‐phase HPLC separations of the derivatives of several representative guanidino compounds in human blood have been achieved with gradients consisting of aqueous formic acid and methanol. Fluorescence detection yields quantification limits of about 20 μg L–1. Hyphenation with electrospray mass spectrometry has been used to confirm the identity of the derivatives.