1,723,152 research outputs found
Hansenula polymorpha NMR2 and NMR4, two new loci involved in nitrogen metabolite repression.
No full textIn the yeast Hansenula polymorpha (Pichia angusta) nitrate assimilation is tightly regulated and subject to a dual control: nitrogen metabolite repression (NMR), triggered by reduced nitrogen compounds, and induction, elicited by nitrate itself. In a previous paper [Serrani, F., Rossi, B. and Berardi, E (2001) Nitrogen metabolite repression in Hansenula polymorpha: the nmrl-l mutation. Curr. Genet. 40, 243-250], we identified five loci (NMR1-NMR5) involved in NMR, and characterised one of them (NMR1), which likely identifies a regulatory factor. Here, we describe two more mutants, namely nmr2-1 and nmr4-1. The first one possibly identifies a regulatory factor involved in nitrogen metabolite repression by various nitrogen sources alternative to ammonium. The second one, apparently involved in ammonium assimilation, probably has sensor functions
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
Influence of tonsillectomy on the progression of mesangioproliferative glomerulonephritis
No full textNephrol Dial Transplant. 2010 Aug;25(8):2583-9. Epub 2010 Mar 2.
Influence of tonsillectomy on the progression of mesangioproliferative glomerulonephritis.
Piccoli A, Codognotto M, Tabbi MG, Favaro E, Rossi B.
Source
Department of Medical and Surgical Sciences, Nephrology Clinic, University of Padova, Padova, Italy. [email protected]
Abstract
BACKGROUND:
Little information is available about the efficacy of tonsillectomy on long-term renal survival of patients with primary IgA nephropathy (IgAN).
METHODS:
In this retrospective cohort study, we considered 61 patients with IgAN who had tonsillectomy (n = 15) or not (n = 46) and compared them with 121 control patients with mesangioproliferative glomerulonephritis (MesGN) free of IgA deposits, who had tonsillectomy (n = 49) or not (n = 72). We evaluated the progression from a normal function [estimated glomerular filtration rate 60-220 mL/min/1.73 m(2), chronic kidney disease (CKD) stage 1 and 2] to a moderate renal dysfunction in CKD stage 3, which was considered the outcome.
RESULTS:
The mean duration of follow-up was 250 months (12-300 months) in the whole group of 182 patients. The survival to progression to stage 3 was 88% after 10 years, 71% after 20 years and 53% after 25 years. It was 72% after 20 years in both groups. Tonsillectomy was not significantly associated with CKD progression. Significant prognostic factors were age (P = 0.01), initial CKD stage (P = 0.03), proteinuria (P = 0.03), persistent proteinuria (P < 0.001) and diastolic blood pressure (P = 0.01). In the multivariate analysis (Cox model), there was no significant effect of tonsillectomy adjusted for the type of glomerulonephritis, initial CKD stage, persistent proteinuria, diastolic blood pressure and age. Only persistent proteinuria adjusted for the other factors was significantly associated with CKD progression (hazard ratio of 6.2, 95% confidence interval 3.1-12.7, P < 0.001).
CONCLUSIONS:
Tonsillectomy was not associated with a different progression rate of IgAN nor of MesGN after 20 years of follow-up
Variations 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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Visual-spatial processing in children with Developmental Dyspraxia: fist data on a test of Mental Rotation
No full text
- …
