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991.
Media literacy interventions partly aim at preventing undesirable media effects at a later point of time. However, longitudinal research on the interaction between media literacy education and media effects is lacking. In this longitudinal study among 1,947 13–25-year-olds, we started to address this lacuna by examining the potential of porn literacy education at schools to attenuate the longitudinal relationship between exposure to sexually explicit Internet material (SEIM) and views of women as sex objects. A two-way interaction effect emerged: The relationship between SEIM and sexist views became weaker, the more users had learned from porn literacy education. No gender or age differences occurred. This study thus provides some first evidence for the role of media education in reducing undesirable media effects. 相似文献
992.
Multimodal Bioactivation of Hydrophilic Electrospun Nanofibers Enables Simultaneous Tuning of Cell Adhesivity and Immunomodulatory Effects 下载免费PDF全文
Laura Wistlich Juliane Kums Angela Rossi Karl‐Heinz Heffels Harald Wajant Jürgen Groll 《Advanced functional materials》2017,27(46)
Biomaterials research usually focuses on functional and structural mimicry of the extracellular matrix or tissue hierarchy and morphology. Most recently, material‐induced modulatory effects on the immune system to arouse a healing response is another upcoming strategy. Approaches, however, that integrate both aspects to induce healing and facilitate specific cell adhesion are so far little explored. This study exploits manifold but chemical crosslinker free functionalization of hydrophilic and nonadhesive electrospun fiber surfaces with peptides for controlled cell adhesion, and with neutralizing antibodies targeting the master cytokine tumor necrosis factor (TNF) to dampen proinflammatory reactions by the fiber adherent cells. It is demonstrated that cell attachment and immunomodulatory properties of a textile can be tailored at the same time to generate meshes that combine immunosuppressive activity with specific cell adhesion properties. 相似文献
993.
Lohier JF Foucoin F Jaffrès PA Garcia JI Sopková-de Oliveira Santos J Perrio S Metzner P 《Organic letters》2008,10(6):1271-1274
A straightforward and high-yielding access to various [2.2]paracyclophanes possessing a sulfur-based functional group is reported, the key step being a SEAr reaction mediated by a sulfonium salt. The versatility of the methodology was exemplified by an original application in sulfenate salt chemistry, from which a remarkable chirality transfer was observed. 相似文献
994.
Toribio L del Nozal MJ Bernal YL Alonso C Jiménez JJ 《Journal of separation science》2008,31(8):1307-1313
The semipreparative chiral separation of lansoprazole and two related compounds (pantoprazole and rabeprazole) using supercritical fluid chromatography (SFC) is presented in this work. Different loads were evaluated in order to obtain high enantiomeric purities and production rates. The volumes injected were 1, 2 and 4 mL. The concentrations of the racemic mixtures were 3 and 6 g/L for lansoprazole and 1.5 g/L for pantoprazole and rabeprazole. In all the cases, the recoveries, for a purity higher than 99.9%, were better for the second eluted enantiomer than for the first one. This fact conditioned the production rate of the first eluted enantiomer that, considering a fixed purity, was always lower than that obtained for the other one. In the case of lansoprazole it was possible to obtain 0.025 and 0.090 mg/min of the first and second eluted enantiomer, respectively, with an enantiomeric purity of 99.9%. For rabeprazole enantiomers 0.037 and 0.062 mg/min, and in the case of pantoprazole the results were better (0.062 and 0.122 mg/min) due to the higher resolution. 相似文献
995.
Mercolini L Addolorata Saracino M Bugamelli F Ferranti A Malaguti M Hrelia S Raggi MA 《Journal of separation science》2008,31(6-7):1007-1014
An original analytical method has been developed for the determination of the antioxidants trans-resveratrol (t-RSV) and cis-resveratrol (c-RSV) and of melatonin (MLT) in red and white wine. The method is based on HPLC coupled to fluorescence detection. Separation was obtained by using a RP column (C8, 150 mm x 4.6 mm id, 5 mum) and a mobile phase composed of 79% aqueous phosphate buffer at pH 3.0 and 21% ACN. Fluorescence intensity was monitored at lambda = 386 nm while exciting at lambda = 298 nm, mirtazapine was used as the internal standard. A careful pretreatment of wine samples was developed, using SPE with C18 cartridges (100 mg, 1 mL). The calibration curves were linear over the following concentration ranges: 0.03-5.00 ng/mL for MLT, 3-500 ng/mL for t-RSV and 1-150 ng/mL for c-RSV. The LOD values were 0.01 ng/mL for MLT, 1 ng/mL for t-RSV and 0.3 ng/mL for c-RSV. Precision data, as well as extraction yield and sample purification results, were satisfactory. Thus, the method seems to be suitable for the analysis of MLT and resveratrol isomers in wine samples. Moreover, wine total polyphenol content and antioxidant activity were evaluated. 相似文献
996.
Benzodiazepines (BZDs) are often prescribed to schizophrenic or depressed patients, as a part of polypharmacy regimens. An HPLC method has been developed for the simultaneous determination of 15 BZDs in human plasma. Separation was obtained by using a C8 RP column and a mobile phase composed of 65% aqueous phosphate buffer at pH 3.0 and 35% ACN. The UV detector was set at 220 nm and clomipramine was used as the internal standard. A careful pretreatment procedure of plasma samples was developed, using SPE with C1 cartridges, which gives high extraction yields (> 97%). The LOQs were always lower than 7.6 ng/mL and the LODs always lower than 2.6 ng/mL for all analytes. The method was successfully applied to plasma samples from depressed and schizophrenic patients undergoing polypharmacy with one or more BZDs. Precision data, as well as accuracy results, were satisfactory and no interference from other drugs was found. Hence, the method seems to be suitable for the therapeutic drug monitoring (TDM) of patients undergoing therapy with one or more BZDs. 相似文献
997.
Zarei M Kirsch S Müthing J Bindila L Peter-Katalinić J 《Analytical and bioanalytical chemistry》2008,391(1):289-297
The coupling of nano high-performance liquid chromatography (nanoHPLC) with matrix-assisted laser desorption/ionization (MALDI)
mass spectrometry (MS) via an automatic spotting roboter was developed and adapted for the first time for the analysis of
complex mixtures of glycosphingolipids (GSLs). The 2,5-dihydroxybenzoic acid and 6-azo-2-thiothymine matrix systems were adjusted
to concurrently meet the requirements for reproducible and homogeneous crystal formation with the liquid chromatography (LC)
eluent under the variable LC solvent composition over the course gradient and high ionization efficiency of the GSL species,
without the need for recrystallization. Precise adjustment of the automatic spotting parameters in terms of matrix flow rate,
on-tip collection time of the matrix/LC eluent solution and the matrix spotting mode, i.e., continuous and discontinuous,
was accomplished to collect individually nanoHPLC-separated species within distinct spots and consequently recover by MALDI
MS screening all major and minor GSL species in the mixtures. The nanoHPLC/MALDI MS coupling protocol was developed and applied
to a mixture of neutral GSLs purified from human erythrocytes and a monosialoganglioside mixture expressed by the murine MDAY-D2
cell line. Additionally, on-line nanoHPLC/MALDI doping with lithium cations of individually separated neutral GSLs was introduced
to enhance data interpretation of the GSL MS pattern, while preserving the same level of information and ultimately to enhance
structural assignment of components of interest. The method is demonstrated to be highly sensitive, reaching the low femtomole
level of detection of individual GSL species and is highlighted as a versatile analytical tool for glycolipidomic studies.
Figure
Automatic LC/MALDI MS profiling of glycosphingolipids
Mostafa Zarei and Stephan Kirsch contributed equally to this work. 相似文献
998.
Choi Yun Sung; Garcia Domingo; Maestre Manuel; Martin Miguel 《Quarterly Journal of Mathematics》2008,59(4):455-474
We study the relation between the polynomial numerical indicesof a complex vector-valued function space and the ones of itsrange space. It is proved that the spaces C(K, X) and L(µ,X) have the same polynomial numerical index as the complex Banachspace X for every compact Hausdorff space K and every -finitemeasure µ, which does not hold any more in the real case.We give an example of a complex Banach space X such that, forevery k 2, the polynomial numerical index of order k of X isthe greatest possible, namely 1, while the one of X** is theleast possible, namely kk/(1–k). We also give new examplesof Banach spaces with the polynomial Daugavet property, namelyL(µ, X) when µ is atomless, and Cw(K, X), Cw*(K,X*) when K is perfect. 相似文献
999.
Stephan Ramon Garcia 《Integral Equations and Operator Theory》2008,60(3):357-367
If denotes the polar decomposition of a bounded linear operator T, then the Aluthge transform of T is defined to be the operator . In this note we study the relationship between the Aluthge transform and the class of complex symmetric operators (T iscomplex symmetric if there exists a conjugate-linear, isometric involution so that T = CT*C). In this note we prove that: (1) the Aluthge transform of a complex symmetric operator is complex symmetric, (2) if T is complex symmetric, then and are unitarily equivalent, (3) if T is complex symmetric, then if and only if T is normal, (4) if and only if T
2 = 0, and (5) every operator which satisfies T
2 = 0 is necessarily complex symmetric.
This work partially supported by National Science Foundation Grant DMS 0638789. 相似文献
1000.
Aurlien Pitois Laura Aldave de Las Heras Maria Betti 《International journal of mass spectrometry》2008,270(3):118-126
Determination of fission products and of their isotopic composition is of high importance for the characterisation and complete inventory of nuclear fuels. Radiometric and mass spectrometric methods, which are currently used, enable only an incomplete determination of the fission products. Radiometric methods cannot be applied to all fission products and mass spectrometric methods are hindered by the existence of isobaric interferences, therefore a previous chemical separation is required before mass spectrometric analysis. Capillary electrophoresis (CE) has been coupled with inductively coupled plasma mass spectrometry (both ICP-QMS and ICP-SFMS). Typical detection limits of 6 ng/mL and 4 pg/mL for caesium as well as 8 ng/mL and 7 pg/mL for lanthanides have been obtained by CE-ICP-QMS and CE-ICP-SFMS, respectively. In addition to these very low detection limits, the procedures present the advantages to be fast (6 min for caesium and 13 min for lanthanides, respectively), to require a low microliter range sample volume and a nanoliter range injection volume. The radiation dose for the personnel as well as the volume of nuclear liquid wastes generated during the measurements are consequently reduced.The procedures have been applied to nuclear samples from PUREX process and leachates from MOX fuels. 相似文献