1,721,068 research outputs found
Prefazione a: Città e mare: Palermo dalle vedute dell’800 alla fotografia contemporanea
No full textComplexation of the sunscreen agent, 4-methylbenzylidene camphor with cyclodextrins. Effect on photostability and human stratum corneum penetration
No full textThe interaction between the sunscreen agent, 4-methylbenzylidene camphor (4-MBC) and hydrophilic α-, p- and γ-cyclodextrin derivatives was investigated in water by phase-solubility analysis. Among the studied cyclodextrins, random methyl-β-cyclodextrin (RM-β-CD) had the greatest solubilizing activity. The complexation of the sunscreen agent with RM-p-CD was confirmed by nuclear magnetic resonance spectroscopy and powder X-ray diffractometry. The light-induced decomposition of 4-MBC in emulsion vehicles was markedly decreased by complexation with RM-p-CD (the extent of degradation, determined by HPLC, was 7.1% for the complex compared to 21.1% for free 4-MBC). The influence of RM-P-CD on the human skin penetration of the sunscreen was investigated in vivo using the tape stripping method, a useful procedure for selectively removing the outermost cutaneous layers. Considerable quantities (21.2-25.1% of the applied dose) of 4-MBC permeated in the stratum corneum. However, no significant differences in the amounts of UV filter in the 10 first strips of the horny layer were observed between the formulations containing 4-MBC free or complexed with RM-p-CD. Therefore, RM-p-CD complexation did not alter the retention of 4-MBC in the superficial layers of the stratum corneum, where its action is more desirable
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Reversed-phase HPLC study on the in vitro enzymic degradation of dermorphin
No full textA high-performance liquid chromatographic (HPLC) method for the separation of the opioid heptapeptide dermorphin and related fragments has been developed. The chromatographic system was applied in the study of the kinetics of degradation of dermorphin (Der) in various tissues. Der was found to be extremely resistant to human and rat plasma (T 1/2 greater than 180 min). Upon incubation with homogenates of rat brains and kidneys, Der was cleaved with a half-life of 20.8 +/- 2.2 min and 2.4 +/- 0.3 min respectively. The catabolite formed was identified, in both tissues, as the N-terminal tetrapeptide H-Tyr-D-Ala-Phe-Gly-OH. The stability to rat kidney and brain of the N-terminal hexa- and pentapeptides and of the [4 psi 5, NHCO] Der analogue was also investigated. The nature of the enzyme systems involved in the in vitro degradations is discussed
Microparticelle lipidiche - Veicolazione del Butil metossidibenzoilmetano
No full textLa veicolazione del BMDBM in microparticelle lipidiche permette di ridurne in maniera significativa la decomposizione indotta dalla luce
Formulations containing Ursodeoxycholic acid for the improvement of the dissolution behaviour of drug.
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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