bluuebunny/crossref_metadata_2025_split huggingface dataset:
Glaucoma: mode of action and properties of current treatments
Authors: McAllister FRCS James 
Published: February 2007

AbstractOur Drug review of glaucoma management describes the concept of target intraocular pressures and the properties of the drugs employed in primary open‐angle glaucoma. This is followed by an analysis of prescription data, sources of further information and the Datafile. Copyright © 2006 Wiley Interface Ltd
Electrical properties of CuGaSe2 single crystals and polycrystalline coevaporated thin films
Authors: Amara A. , Rezaiki W. , Ferdi A. , Hendaoui A. , Drici A. , Guerioune M. , Bernède J. C. , Morsli M. 
Published: February 2007

Abstract CuGaSe2 single crystals were grown by iodine vapour transport method, whereas polycrystalline thin films were obtained by coevaporation technique from three sources. The variation of the hole concentration with temperature of CuGaSe2 single crystal in the high temperature region is interpreted assuming thermal activation in the valence band. The density of states effective mass of the holes is deduced. Acceptor and donor concentrations as well as their compensation ratio are reported. The temperature dependence of the hole mobility in valence band is analysed by taking into account several scattering mechanisms of the charge carriers. To account for the temperature dependant conductivity of polycrystalline CuGaSe2 thin film, grain boundary conduction process was suggested. Quantitative values of the mean potential barrier height at grain boundaries and the standard deviation are reported. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comment on “Transport Properties of Tl5Te3 Single Crystals” [phys. stat. sol. (a) Vol. 191, No. 1, 322–329 (2002)]
Authors: Cankurtaran M. , Çelik H. 
Published: February 2007

AbstractRecently, Gamal et al. [phys. stat. sol. (a) 191, 322 (2002)] reported the results of electrical conductivity, Hall effect and thermoelectric power (TEP) measurements on Tl5Te3 single crystals. The samples used in the study were p‐type semiconductors. From the experimental data for the temperature dependence of TEP, Gamal et al. determined the values of 1.6 × 10–41 kg and 1.5 × 10–40 kg, respectively, for the effective masses of electrons and holes in p‐type Tl5Te3, which are about ten orders of magnitude smaller than the free electron mass, 9.11 × 10–31 kg. We argue that the anomalously small values obtained for the effective mass of charge carriers in Tl5Te3 have no physical significance. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pressure‐induced ferroelectric to antiferroelectric phase transformation in porous PZT95/5 ceramics
Authors: Zeng T. , Dong X. L. , He H. L. , Chen X. F. , Yao C. H. 
Published: February 2007

AbstractThe hydrostatic pressure‐induced ferroelectric to antiferroelectric (FE–AFE) phase transformation of PZT95/5 ceramics was investigated as a function of porosity, pore shape and pore size. FE–AFE phase transformations were more diffuse and occurred at lower hydrostatic pressures with increasing porosity. The porous PZT95/5 ceramics with spherical pores exhibited higher transformation pressures than those with irregular pores. Moreover, FE–AFE phase transformations of porous PZT95/5 ceramics with polydisperse irregular pores were more diffuse than those of porous PZT95/5 ceramics with monodisperse irregular pores. The relation between pore structure and hydrostatic pressure‐induced FE–AFE transformation was established according to stress concentration theory. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multipole expansions for numerical orbital products
Authors: Talman James D. 
Published: February 2007

AbstractThe product of two numerically defined atomic angular momentum orbitals at different centers is considered. The product can be expanded about a third center on the line segment joining the two centers. A numerical procedure for evaluating the expansion functions is developed. The application of the expansion to the evaluation of four‐center electron–electron repulsion integrals is discussed. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Multiplex target protein imaging in tissue sections by mass spectrometry – TAMSIM
Authors: Thiery Gwendoline , Shchepinov Mikhail S. , Southern Edwin M. , Audebourg Anne , Audard Virginie , Terris Benoît , Gut Ivo G. 
Published: February 2007

AbstractMatrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐MS) is becoming a popular tool for imaging histological sections. Currently, this technology is used to image naturally occurring molecules. Here we report a novel development for multiplex imaging of candidate proteins. Rather than detecting whatever molecules happen to be present and above the detection threshold in the desorption pixel, we attach photocleavable mass tags to antibodies to target proteins. ‘Staining’ of histological sections is carried out similarly to common immunohistochemical procedures with chemiluminescent or fluorescent detection using all antibodies of a multiplex simultaneously. Mass tags with discrete masses are released from their respective antibodies by a laser pulse at 355 nm without added matrix. After scanning, mass spectrometry images are created for the mass of each tag. In contrast to fluorescent tags, mass tags do not exhibit mutual quenching. Sections of healthy human pancreatic tissue were imaged to visualize synaptophysin in neuroendocrine cells, and sections from human lymph node and liver invaded by metastatic melanoma to localize the cancer markers PS100 and HMB45 simultaneously. All these proteins are below the detection threshold of direct MALDI‐MS imaging. This method is termed TAMSIM for TArgeted multiplex Mass Spectrometry IMaging. Copyright © 2007 John Wiley & Sons, Ltd.
A modified peptide mapping strategy for quantifying site‐specific deamidation by electrospray time‐of‐flight mass spectrometry
Authors: Stroop Steven D. 
Published: February 2007

AbstractA modified peptide mapping strategy using electrospray time‐of‐flight mass spectrometry with high‐performance liquid chromatography (HPLC/MS) provides an improved measure of deamidation by performing proteolytic digestion at low temperature (4°C), low pH (6.0) and in organic solvent (≥10% acetonitrile). HPLC resolution of the native (N) and deamidated (D) peptides is achieved, and the ratio of ion counts is converted into percent deamidation. The percent deamidation is established for a reference lot using a time course of digestion (24–120 h) and extrapolation to time zero. Test samples are compared against the reference lot to quantitate changes in site‐specific deamidation. A recombinant purified protein (antigen A) having a single labile Asn‐Gly site is analyzed using this strategy. The N and D peptides from an endoproteinase Lys C (Lys C) digestion (pH 6, 4°C) resolve to near homogeneity on HPLC which results in equivalent percent deamidation when calculated by either UV or ion counts. Deamidation increases with time and pH of proteolysis. Lys C peptide maps of antigen A and bovine serum albumin (BSA) digested at pH 5–8 are comparable. A Lys C digestion time course of a reference lot of antigen A extrapolates to 18% deamidation of the Asn‐Gly site at time zero. This strategy may be generally applicable to protease–protein combinations for improved accuracy in measuring site‐specific deamidation by peptide mapping LC/MS. Copyright © 2007 John Wiley & Sons, Ltd.
Rapid structural elucidation of composite bacterial hopanoids by atmospheric pressure chemical ionisation liquid chromatography/ion trap mass spectrometry
Authors: Talbot Helen M. , Rohmer Michel , Farrimond Paul 
Published: February 2007

AbstractBacteriohopanepolyols (BHPs) are membrane lipids produced by a wide range of eubacteria. Their use, however, as molecular markers of bacterial populations and processes has until recently been hampered by the lack of a suitable rapid method for fingerprinting their composition in complex environmental matrices. New analytical procedures employing ion trap mass spectrometry now allow us to investigate the occurrence of BHPs in diverse biological and environmental samples including bacterial cultures, soils, and recent and ancient sediments. Here, we describe the structural characterisation using atmospheric pressure chemical ionisation liquid chromatography/ion trap mass spectrometry (APCI‐LC/MSn) of a number of previously identified but less commonly occurring BHPs such as adenosylhopane and ribonylhopane. Many of the structures described here have previously only been reported in one or just a small number of cultured organisms having been isolated from large amounts of cellular mass (4–26 g) and identified by nuclear magnetic resonance (NMR) techniques after purification of individual compounds. Now, having established characteristic APCI fragmentation patterns, it is possible to rapidly screen many more bacterial cultures using only small amounts of material (<50 mg) as well as environmental samples for these atypical structures and a rapidly growing suite of novel structures. Copyright © 2007 John Wiley & Sons, Ltd.
Infusion mass spectrometry as a fingerprint to characterize varnishes in oil pictorial artworks
Authors: Peris‐Vicente J. , Garrido‐Medina R. , Simó‐Alfonso E. , Gimeno‐Adelantado J. V. , Doménech‐Carbó M. T. 
Published: February 2007

AbstractMass spectrometry methodology to characterize drying oil used as binding media and varnishes in pictorial artworks, prior to conservation or restoration treatment, is proposed. The analytical treatment requires prior basic hydrolysis of the samples to release the fatty acids: caprylic, pelargonic, capric, sebacic, azelaic, suberic, eicosanoic, lauric, mirystic, palmitic, linolenic, linoleic, oleic and stearic, followed by separation from the matrix by a hexane/water extraction. After removing the solvent, the remaining solid is dissolved in potassium hydroxide, propanol and methanol. The mixture is directly infused into a mass spectrometer without any previous derivatization or separation steps. The detector is operated in electrospray negative ion mode and the [MH]− ions of the fatty acids enable identification of the acids. Obtained data for fatty acid ion abundances are analyzed by linear discriminant analysis. The drying oils studied (linseed, poppy seed and walnut) were satisfactorily distinguished. The analytical method shows adequate sensitivity, reproducibility, speed and ease. The proposed methodology has been successfully applied to samples from artistic samples belonging to the Cultural Heritage of Valencia (Spain). Copyright © 2007 John Wiley & Sons, Ltd.
Fractionation factors for stable isotopes of N and O during N2O reduction in soil depend on reaction rate constant
Authors: Vieten Beatrix , Blunier Thomas , Neftel Albrecht , Alewell Christine , Conen Franz 
Published: February 2007

AbstractNitrous oxide (N2O) is a major greenhouse gas that is mainly produced but also reduced by microorganisms in soils. We determined factors for N and O isotope fractionation during the reduction of N2O to N2 in soil in a flow‐through incubation experiment. The absolute value of the fractionation factors decreased with increasing reaction rate constant. Reaction rates constants ranged from 1.7 10−4 s−1 to 4.5 10−3 s−1. The minimum, maximum and median of the observed fractionation factors were for N −36.0‰, −1.0‰ and −9.3‰ and for O −74.0‰, −6.9‰ and −26.3‰, respectively. The ratio of O isotope fractionation to N isotope fractionation was 2.4 ± 0.3 and it was independent from the reaction rate constants. This leads us to conclude that fractionation factors are variables while their ratio in this particular reaction might be a constant. Copyright © 2007 John Wiley & Sons, Ltd.
Viral metagenomics
Authors: Delwart Eric L. 
Published: February 2007

AbstractCharacterisation of new viruses is often hindered by difficulties in amplifying them in cell culture, limited antigenic/serological cross‐reactivity or the lack of nucleic acid hybridisation to known viral sequences. Numerous molecular methods have been used to genetically characterise new viruses without prior in vitro replication or the use of virus‐specific reagents. In the recent metagenomic studies viral particles from uncultured environmental and clinical samples have been purified and their nucleic acids randomly amplified prior to subcloning and sequencing. Already known and novel viruses were then identified by comparing their translated sequence to those of viral proteins in public sequence databases. Metagenomic approaches to viral characterisation have been applied to seawater, near shore sediments, faeces, serum, plasma and respiratory secretions and have broadened the range of known viral diversity. Selection of samples with high viral loads, purification of viral particles, removal of cellular nucleic acids, efficient sequence‐independent amplification of viral RNA and DNA, recognisable sequence similarities to known viral sequences and deep sampling of the nucleic acid populations through large scale sequencing can all improve the yield of new viruses. This review lists some of the animal viruses recently identified using sequence‐independent methods, current laboratory and bioinformatics methods, together with their limitations and potential improvements. Viral metagenomic approaches provide novel opportunities to generate an unbiased characterisation of the viral populations in various organisms and environments. Copyright © 2007 John Wiley & Sons, Ltd.
Semicopositive linear complementarity systems
Authors: Shen Jinglai , Pang Jong‐Shi 
Published: February 2007

AbstractInspired by the dynamic complementarity problem introduced by Mandelbaum, we define several matrix classes in terms of some integral conditions and discuss their connection with the existing class of strictly semicopositive matrices in linear complementarity theory. Using a time‐stepping approximation scheme, we establish the existence of an integrable solution to a class of index‐one linear complementarity systems (LCSs) involving these matrices, and that such a solution is ‘short‐time’ unique if the initial state belongs to a semiobservable cone defined in the recent paper (IEEE Trans. Autom. Control2007, in press). In contrast to the existing well‐posedness theory for the LCS, our result is based on a well‐known matrix property that has not been used in the LCS literature before. Copyright © 2007 John Wiley & Sons, Ltd.
Phase transition of the minimum degree random multigraph process
Authors: Kang Mihyun , Seierstad Taral Guldahl 
Published: February 2007

AbstractWe study the phase transition of the minimum degree multigraph process. We prove that for a constant hg ≈︁ 0.8607, with probability tending to 1 as n → ∞, the graph consists of small components on O(log n) vertices when the number of edges of a graph generated so far is smaller than hgn, the largest component has order roughly n2/3 when the number of edges added is exactly hgn, and the graph consists of one giant component on Θ(n) vertices and small components on O(log n) vertices when the number of edges added is larger than hgn. © 2007 Wiley Periodicals, Inc. Random Struct. Alg., 2007
ARXPS investigation of diffusion as a limiting process in the incorporation of adatoms into polystyrene surfaces treated by nitrogen plasmas
Authors: Paynter R. W. , Roy‐Guay D. , Parent G. , Ménard M. 
Published: February 2007

AbstractPolystyrene films were exposed to nitrogen plasmas for periods up to 4 min. ARXPS measurements revealed the presence of oxygen and nitrogen in the surface because of the plasma treatment. The depth profiles of these adatoms were determined by fitting a Thomas–Windle model profile to the data. As found previously, the best‐fit depth profiles resembled a step function, consistent with case II diffusion. However, the depth of penetration of the adatom species into the polymer surface was not found to vary with plasma duration, which is inconsistent with Case II diffusion, and provides evidence that diffusion processes do not limit the loading of adatom species into the surface during nitrogen plasma treatment. A possible reason for the generation of erroneous step function depth profiles is discussed. Copyright © 2007 John Wiley & Sons, Ltd.
New confidence bounds for QT studies
Authors: Boos Dennis D. , Hoffman David , Kringle Robert , Zhang Ji 
Published: February 2007

AbstractThe proposed guidelines for the assessment of the effect of new pharmaceutical agents on the QT interval (beginning of QRS complex to end of T wave on the electrocardiogram) are based on the maximum of a series over time of simple one‐sided 95 per cent upper confidence bounds. This procedure is typically very conservative as a procedure for obtaining a 95 per cent bound for the maximum of the population parameters. This paper proposes new bounds for the maximum, both analytical and bootstrap‐based, that are lower but still achieve correct coverage in the context of crossover and parallel designs for the most realistic portions of the parameter space. Copyright © 2007 John Wiley & Sons, Ltd.
Assessment of sediment toxicity during anaerobic biodegradation of vegetable oil using Microtox® and Hyalella azteca bioassays
Authors: Li Zhengkai , Lee Kenneth , Cobanli Susan E. , King Thomas , Wrenn Brian A. , Doe Kenneth G. , Jackman Paula M. , Venosa Albert D. 
Published: February 2007

AbstractThe potential ecological impacts of anaerobic degradation of vegetable oil on freshwater sediments were investigated. Sediment toxicity was evaluated using two regulatory biotests: the Microtox® Solid Phase Test and an amphipod (Hyalella azteca) bioassay. The results of the Microtox test showed that the toxicity of the vegetable‐oil‐contaminated sediments (about 17–33 g oil/kg dry sediments) increased after 2 weeks incubation and then decreased to near background levels after incubation for 8 weeks under anaerobic conditions. The amphipod toxicity bioassay showed that the toxicity of fresh contaminated sediments decreased over time and returned to background levels within 8 weeks. These results suggest that the impact of vegetable oils on organisms within sediments may be limited. To account for the significance of environmental conditions, additional studies over a wide range of incubation conditions (e.g., temperature, nutrient concentration) and other test organisms at various trophic levels are recommended for both acute and chronic toxicity assessment. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 1–8, 2007.
Phosphate regulates uranium(VI) toxicity to Lemna gibba L. G3
Authors: Mkandawire Martin , Vogel Kerstin , Taubert Barbara , Dudel E. Gert 
Published: February 2007

AbstractThe influence of phosphate on the toxicity of uranium to Lemna gibba G3 was tested in semicontinuous culture with synthetic mine water developed as an analogue of surface water of two abandoned uranium mining and ore processing sites in Saxony, Germany. Six concentrations of uranium were investigated under five different supply regimes of PO43− at constant pH (7.0 ± 0.5) and alkalinity (7.0 ± 1.6 mg L−1 total CO32−). The results showed significant inhibition of specific growth rates in cultures exposed to the highest uranium concentrations (3500 and 7000 μg U L−1) at lowest PO43− supply of 0.01 mg L−1. An increase of phosphate concentration from 0.01 to 8.0 mg L−1 resulted in an increase of EC50 from 0.9 ± 0.2 to 7.4 ± 1.9 mg L−1 (significant with Student's t test, P > 0.05). The accumulation of uranium in L. gibba increased exponentially with the increase in uranium concentration in cultures with 0.01 and 0.14 mg PO43− L−1. Accumulation also increased significantly when PO43− supply was increased from 0.14 to 1.36 mg PO43− L−1 for all uranium concentrations. However, as the supply of PO43− gradually increased from 1.36 to 8.0 mg PO43− L−1, uranium bioaccumulation increased slightly but insignificantly before leveling off. Uranium speciation modeling with PhreeqC geochemical code predicted increases in the proportions of uranyl phosphate species when PO43− concentrations increase in the media. Most of these uranyl phosphate species have a high probability of precipitation [saturation indices (SI) > 0.93]. Therefore, the alleviation of uranium toxicity to L. gibba with phosphates is due to interactions among components of the media, mainly uranyl and phosphate which results in precipitation. Consequently, bioavailable fractions of uranium to L. gibba are reduced. This might explain lack of consistent EC50 values for uranium to most aquatic organisms. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 9–16, 2007.
Effects of dietary boron on cervical cytopathology and on micronucleus frequency in exfoliated buccal cells
Authors: Korkmaz Mehmet , Uzgören Engin , Bakırdere Sezgin , Aydın Fırat , Ataman O. Yavuz 
Published: February 2007

AbstractRecent evidence indicates that boron and borates may have anticarcinogenic properties. In this study, we have investigated the incidence of adverse cytological findings in cervical smears and the micronucleus (MN) frequency in women living in boron‐rich and boron‐poor regions. Cervical smears were prepared from 1059 women with low socioeconomic status; 472 of the women lived in relatively boron‐rich rural areas, while 587 lived in relatively boron‐poor regions. The average and standard deviation values for the age of the women screened with the cervical Pap smear test were 41.55 ± 8.38. The mean dietary intake of boron was 8.41 mg/day for women from the boron‐rich regions, and 1.26 mg/day for women living in the boron‐poor regions (P < 0.0001). Women from the boron‐rich regions had no cytopathological indications of cervical cancer, while there were cytopathological findings for 15 women from the boron‐poor areas (χ2 = 10.473, P < 0.05). Sixty women, 30 from each region, were chosen for evaluating MN frequencies in exfoliated buccal cells. MN frequencies for women from the boron‐rich and boron‐poor regions were not significantly different (t = −0.294, P > 0.05). Also, there were no significant correlations between age and MN frequency for women from both the boron‐rich (r = 0.133, P = 0.48, P > 0.05) and boron‐poor (r = −0.033, P = 0.861, P > 0.05) regions. The results suggest that ingestion of boron in the drinking water decreases the incidence of cervical cancer‐related histopathological findings. There was no correlation between the pathological findings from the cervical smears and buccal cell MN frequency suggesting that the two study populations were exposed equally to gentotoxic agents. Nonetheless, cervical cancer‐related histopathological findings should be validated by other researchers. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 17–25, 2007.