1,720,998 research outputs found
Gain of Function of Tbx1 Affects Pharyngeal and Heart Development in the Mouse
No full textMammalian development is highly sensitive to Tbx1 gene dosage reduction. Gene function insights can also be learned from increased or ectopic expression. The authors generated a novel mouse transgenic line, named COET, which expresses Tbx1 upon Cre-mediated recombination. The authors crossed this transgenic line with Tbx1(Cre) animals to activate expression in the Tbx1-expression domain. Compound mutant COET;Tbx1(Cre/+) animals died after birth and showed heart enlargement. At E18.5, compound mutants showed ventricular septal defects and thymic abnormalities. The authors crossed compound mutants into a Tbx1 null background to understand whether this phenotype is caused by gene overdosage. Results showed that gene dosage reduction at the endogenous locus could not rescue heart and thymic defects, although the transgene rescued the loss of function phenotype. Thus, the transgenic phenotype appears to be due to gain of function. Resultant data demonstrate that Tbx1 expression must be tightly regulated to be compatible with normal embryonic development. genesis 47:188-195, 2009. (c) 2009 Wiley-Liss, Inc
Le donne imprenditrici, evoluzione del loro ruolo nella storia
No full textUn cammino, quello delle donne imprenditrici, iniziato nell’Antica Roma e tutt’ora in atto, teso alla crescita, ad un più equo riconoscimento, ad una reale ed oggettiva condizione di pari opportunità. Dall’assenza, dalla relegazione al ruolo di moglie e madre, a un lento ma costante affacciarsi della donna nel mondo del lavoro, dominio un tempo dell’uomo.
Un percorso accidentato, visto con sospetto, duro. Da qui nasce la pubblicazione “Le donne imprenditrici, evoluzione del loro ruolo nella storia”, promossa dalla Confesercenti di Napoli e finanziato dalla Camera di Commercio. La curatrice, Francesca Vitelli, ci racconta che«l’idea di questa pubblicazione nasce dalla volontà di restituire al patrimonio collettivo l’esperienza e le imprese di donne invisibili che hanno contribuito, nel tempo, allo sviluppo dell’economia locale. Dalle donne che hanno saputo creare una attività imprenditoriale in epoca romana, passando per l’Ottocento e il Novecento, fino a giungere ai giorni nostri»
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
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