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101.
102.
Christian Gumpenberger Juan Gorraiz Martin Wieland Ivana Roche Edgar Schiebel Dominique Besagni Claire François 《Scientometrics》2013,95(1):277-297
Negative results are not popular to disseminate. However, their publication would help to save resources and foster scientific communication. This study analysed the bibliometric and semantic nature of negative results publications. The Journal of Negative Results in Biomedicine (JNRBM) was used as a role model. Its complete articles from 2002–2009 were extracted from SCOPUS and supplemented by related records. Complementary negative results records were retrieved from Web of Science in “Biochemistry” and “Telecommunications”. Applied bibliometrics comprised of co-author and co-affiliation analysis and a citation impact profile. Bibliometrics showed that authorship is widely spread. A specific community for the publication of negative results in devoted literature is non-existent. Neither co-author nor co-affiliation analysis indicated strong interconnectivities. JNRBM articles are cited by a broad spectrum of journals rather than by specific titles. Devoted negative results journals like JNRBM have a rather low impact measured by the number of received citations. On the other hand, only one-third of the publications remain uncited, corroborating their importance for the scientific community. The semantic analysis relies on negative expressions manually identified in JNRBM article titles and abstracts and extracted to syntactic patterns. By using a Natural Language Processing tool these patterns are then employed to detect their occurrences in the multidisciplinary bibliographical database PASCAL. The translation of manually identified negation patterns to syntactic patterns and their application to multidisciplinary bibliographic databases (PASCAL, Web of Science) proved to be a successful method to retrieve even hidden negative results. There is proof that negative results are not only restricted to the biomedical domain. Interestingly a high percentage of the so far identified negative results papers were funded and therefore needed to be published. Thus policies that explicitly encourage or even mandate the publication of negative results could probably bring about a shift in the current scientific communication behaviour. 相似文献
103.
Dush Claire M. Kamp; Kotila Letitia E.; Schoppe-Sullivan Sarah J. 《Canadian Metallurgical Quarterly》2011,25(3):356
Supportive coparenting after relationship dissolution is associated with increased father involvement which can buffer against the negative effects of parental relationship dissolution. Low-income, at-risk families are much more likely to experience relationship dissolutions; hence, supportive coparenting after dissolution is particularly important in these families. We examined whether relationship (commitment and quality) and child (difficult temperament and gender) characteristics predicted initial levels of, and change in, supportive coparenting after relationship dissolution in the Fragile Families and Child Wellbeing Study (N = 1,603). We used structural equation modeling of latent growth curves to examine four time points collected at the focal child's birth and first, third, and fifth birthdays. Ninety-percent of the mothers had nonmarital births, and about three-quarters had a high school diploma or less education. Overall, supportive coparenting decreased over time. Mothers in more committed relationships prior to the dissolution initially had significantly lower supportive coparenting. But over time, mothers who had been in more committed relationships increased in supportive coparenting. Mothers who had been in higher quality relationships prior to dissolution initially reported more supportive coparenting. At each time point, if a mother was romantically involved with a new partner, she reported significantly lower supportive coparenting compared to mothers who were single. With regard to child characteristics, mothers who reported their child as more difficult had significantly lower initial supportive coparenting. Similar results for fathers are discussed. Overall, the relationship characteristics of parents were important predictors of supportive coparenting both initially and over time. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
104.
Combining scanning force and fluorescent microscopy allows simultaneous identification of labeled biomolecules and analysis of their nanometer level architectural arrangement. Fluorescent polystyrene nano-spheres were used as reliable objects for alignment of optical and topographic images. This allowed the precise localization of different fluorescence particles within complex molecular assemblies whose structure was mapped in nanometer detail topography. Our experiments reveal the versatility of this method for analysis of proteins and protein–DNA complexes. 相似文献
105.
Ahmed Sheikh Hassan Anne Sapin Nathalie Ubrich Philippe Maincent Claire Bolzan 《Drug development and industrial pharmacy》2013,39(10):1064-1070
A simple and sensitive high-performance liquid chromatography (HPLC) assay applied to the measurement of ibuprofen in rat plasma has been developed. Two parameters have been investigated to improve ibuprofen detectability using fluorescence detection: variation of mobile phase pH and the use of β-cyclodextrin (β-CD). Increasing the pH value from 2.5 to 6.5 and adding 5 mM β-CD enhanced the fluorescence signal (λexc = 224 nm; λem = 290 nm) by 2.5 and 1.3-fold, respectively, when using standards. In the case of plasma samples, only pH variation significantly lowered detection and quantification limits, down to 10 and 35 ng/mL, respectively. Full selectivity was obtained with a single step for plasma treatment, that is, protein precipitation with acidified acetonitrile. The validated method was applied to a pharmacokinetic study of ibuprofen encapsulated in microspheres and subcutaneously administered to rats. 相似文献
106.
Claire Bourlieu Mariana Ferreira Bruno Barea Valérie Guillard Pierre Villeneuve Stéphane Guilbert Nathalie Gontard 《European Journal of Lipid Science and Technology》2009,111(5):489-498
Four acetostearin products with increasing acetylation degree were synthesized by chemical interesterification followed by fractionation/blending stages. Their physical properties and functional barrier properties were studied and compared to the properties of technical tristearin. Increasing acetylation degree (AD) modified the triacylglycerols crystal habits and probably led to an increase in acyl chain fluidity, which induced, at macroscopic levels, a decrease in solid fat content (SFC), in melting point, in surface and bulk material hydrophobicity, and an increased moisture effective diffusivity. Water vapor permeability (WVP) coefficients of the materials were partially influenced by the AD factor, but also by the development of macroscopic cracks in lipids presenting high SFC. Acetylated stearin up to 47% (acetyl mol/mol of esterified chain) presented the lowest WVP at 20 °C resulting from an adequate balance between hydrophobicity and mechanical properties of the material. 相似文献
107.
Self-concept development in the toddler years. 总被引:1,自引:0,他引:1
108.
MA‐NOTMP: A Triazacyclononane Trimethylphosphinate Based Bifunctional Chelator for Gallium Radiolabelling of Biomolecules 下载免费PDF全文
Sophie Poty Dr. Pauline Désogère Dr. Jakub Šimeček Dr. Claire Bernhard Dr. Victor Goncalves Dr. Christine Goze Dr. Frédéric Boschetti Dr. Johannes Notni Prof. Dr. Hans J. Wester Prof. Dr. Franck Denat 《ChemMedChem》2015,10(9):1475-1479
In the past few years, gallium‐68 has demonstrated significant potential as a radioisotope for positron emission tomography (PET), and the optimization of chelators for gallium coordination is a major goal in the development of radiopharmaceuticals. Methylaminotriazacyclononane trimethylphosphinate (MA‐NOTMP), a new C‐functionalized triazacyclononane derivative with phosphinate pendant arms, presents excellent coordination properties for 68Ga (low ligand concentration, labelling at low pH even at room temperature). A “ready‐to‐be‐grafted” bifunctional chelating agent (p‐NCS‐Bz‐MA‐NOTMP) was prepared to allow 68Ga labelling of sensitive biological vectors. Conjugation to a bombesin(7–14) derivative was performed, and preliminary in vitro experiments demonstrated the potential of MA‐NOTMP in the development of radiopharmaceuticals. This new chelator is therefore of major interest for labelling sensitive biomolecules, and further in vivo experiments will soon be performed. 相似文献
109.
110.
Claire Jamieson 《The Journal of Architecture》2015,20(1):122-151
Nigel Coates graduated from Bernard Tschumi's unit at the Architectural Association in 1974, before joining him in 1977 to develop a new unit together. These were formative years for Coates, a period that shaped his architectural preoccupations for the following decades – yet they remain relatively unexplored. Between 1974 and 1977, Coates produced a number of installation and performance works with the artist Antonio Lagarto and fellow AA graduate Jenny Lowe, influenced by Tschumi's own explorations with the curator RoseLee Goldberg, and their exhibition at the Royal College of Art, A Space: A Thousand Words (1975). The works considered the potential for space to be amplified by the introduction of markers, representations of other spaces and the movement of the body. This article exposes these works for the first time, tracing the changes in Coates's thinking during this period and how it was reflected in the Unit 10 briefs that he and Tschumi developed in the period 1977–80. It chronicles Coates's pivotal trips to New York during 1980–81 to teach at Bennington College, where his exposure to a dynamic club-scene and influential new art would mark a step change in the young architect's trajectory. Charting Coates's development through his own work and his teaching at the AA, the article constructs the background from which the radical architectural group NATØ emerged in 1983. 相似文献