130,829 research outputs found
Studi sulla tradizione manoscritta dell'Eutifrone di Platone: la prima famiglia
No full textIl contributo analizza un ramo della tradizione manoscritta dell’Eutifrone di Platone, dialogo trasmesso nella sua interezza da sessanta testimoni (ante 1600), cui si aggiungono gli excerpta dotati di valore primario del Vat. Pal. 173 (P). La prima famiglia comprende tre manoscritti primari, Bodl. Clarke 39 (B, a. 895), Tubing. Mb 14 (C, XI sec.), Marc. gr. 185 (D, XI o XII sec.), e tredici apografi, di ciascuno dei quali si fornisce in apertura una breve descrizione: se ne esaminano in seguito i rapporti stemmatici che intercorrono tra di loro sulla base di nuove collazioni. Per quanto riguarda l’Eutifrone, B non ha avuto discendenza, mentre la discendenza di C è limitata al solo Laur. Plut. 89 sup. 78 prodotto in ambiente crisolorino: nuovi elementi sono stati individuati riguardo alla storia di C. Tutti i restanti apografi derivano da D, a seguito di ciascuna delle tre stratificazioni diortotiche che hanno interessato il manoscritto, due delle quali ne hanno contaminato il testo con lezioni delle altre due famiglie. Da D+D2 fu copiato un testimone interessante seppure per lo più ignorato dagli studiosi, il Bonon. gr. 3630. Gli apografi di D+D2+d1 si dividono in due ramificazioni: il ‘ramo α’ comprende lo Haun. gr. Gks 415a, 2° e i suoi discendenti Ambros. N 269 sup., e Par. gr. 2011; il ‘ramo ε’ è costituito dal Par. gr. 1810, con la sua copia Laur. Conv. Soppr. 103, dal Vat. gr. 229 e dal Par. gr. 2010, col suo discendente Par. Suppl. gr. 69. Dopo l’ultima diorthosis di d2, D fu copiato da Demetrio Trivolis nell’Esc. Ψ. I. 1, a sua volta modello del Bern. 579, in parte collegato a Costantino Lascaris
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
Asymptomatic homozygous nt 20210 G to A prothrombin polymorphism in two blood donors belonging to two different kindreds
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Application of D-Crustacean Hyperglycemic Hormone Induces Peptidases Transcription and Suppresses Glycolysis-Related Transcripts in the Hepatopancreas of the Crayfish Pontastacus leptodactylus—Results of a Transcriptomic Study
No full textThe crustacean Hyperglycemic Hormone (cHH) is a neuropeptide present in many decapods. Two different chiral isomers are simultaneously present in Astacid crayfish and their specific biological functions are still poorly understood. The present study is aimed at better understanding the potentially different effect of each of the isomers on the hepatopancreatic gene expression profile in the crayfish Pontastacus leptodactylus, in the context of short term hyperglycemia. Hence, two different chemically synthesized cHH enantiomers, containing either L- or D-Phe3, were injected to the circulation of intermolt females following removal of their X organ-Sinus gland complex. The effects triggered by the injection of the two alternate isomers were detected after one hour through measurement of circulating glucose levels. Triggered changes of the transcriptome expression profile in the hepatopancreas were analyzed by RNA-seq. A whole transcriptome shotgun sequence assembly provided the assumedly complete transcriptome of P. leptodactylus hepatopancreas, followed by RNA-seq analysis of changes in the expression level of many genes caused by the application of each of the hormone isomers. Circulating glucose levels were much higher in response to the D-isoform than to the L-isoform injection, one hour from injection. Similarly, the RNA-seq analysis confirmed a stronger effect on gene expression following the administration of D-cHH, while just limited alterations were caused by the L-isomer. These findings demonstrated a more prominent short term effect of the D-cHH on the transcription profile and shed light on the effect of the D-isomer on specific functional gene groups. Another contribution of the study is the construction of a de novo assembly of the hepatopancreas transcriptome, consisting of 39,935 contigs, that dramatically increases the molecular information available for this species and for crustaceans in general, providing an efficient tool for studying gene expression patterns in this organ
Water Tank Simulation of a Dense Fluid Release
No full textThe turbulent velocity field of a dense fluid release has been measured in a water tank experiment carried out in the TURLAB laboratory in Turin (Italy). A vertical density driven current was created releasing a saline solution in a water tank with no mean flow. The experiment reproduces in physical similarity, based on the density Froud number, the release of a dense gas in the atmosphere and the PIV technique has been used to analyse the buoyancy generated velocity field. The high temporal and spatial resolution of the measurements gives a deep insight to the problems of the bouncing of dense gases and of the creation of the outflow velocity at the ground. The experimental findings are used to test and improve an original method for the dispersion of a positively and negatively buoyant plume. The method is based on the idea of Alessandrini and Ferrero (Phys. A 388:1375–1387, 2009) for the treatment of a background substance entrainment into the plume and it consists on the introduction of two fictitious scalars inside the Lagrangian Model SPRAY. The fictitious scalars represent the density and momentum difference between the plume and the environment air that naturally takes into account the interaction between the plume and the environment. As a consequence, no more particles than those inside the plume are released to simulate the entrainment of the background air temperature. In this way the entrainment is properly simulated and the plume sink is calculated from the local property of the flow. The approach is wholly Lagrangian
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Different transcription regulation routes are exerted by L- And D-amino acid enantiomers of peptide hormones
No full textConversion of one or more amino acids in eukaryotic peptides to the D-enantiomer configuration is catalyzed by specific L/D-peptide isomerases and it is a poorly investigated post-translational modification. No common modified amino acid or specific modified position has been recognized, and mechanisms underlying changes in the peptide function provided by this conversion are not widely studied. The 72 amino acid crustacean hyperglycemic hormone (CHH) in Astacidea crustaceans exhibits a co-existence of two peptide enantiomers with either D- or L-phenylalanine as their third residue. It is a pleiotropic hormone regulating several physiological processes in different target tissues and along different time scales. CHH enantiomers differently affect time courses and intensities of examined processes. The short-term effects of the two isomers on gene expression were examined in the hepatopancreas, gills, hemocytes and muscles of the astacid Pontastacus leptodactylus. Gene expression in muscles and hemocytes was not affected by either of the isomers. Two modes of action for CHH were elucidated in the hepatopancreas and the gills: specific gene induction in both organs by D-CHH, and targeted attenuation caused by both enantiomers in the gills. Consequently, a two-receptor system is proposed for conveying the effect of the two CHH isomers. © 2014. Published by The Company of Biologists Ltd
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