130,818 research outputs found
Carta de Antonio González Garbin a Pedro Dorado Montero
No full textCarta de D. Antonio González Garbin a D. Pedro Dorado Montero, encargándole la recogida de tres ejemplares y algún dinero que como liquidación le adeuda el librero salmantino Gabriel Mulas. Adjunta carta de Gabriel Mulas en la que le inserta la orden de entrega
¿Cómo piensan los alumnos entres 16 y 20 años en el infinito?: la influencia de los modelos, las representaciones y los lenguajes matemáticos
No full textThe ideas, results and reflections that we develop, are product of studies and part of investigations (Garbin 2000, 2003, 2005 and Garbin & Azcárate, 2001) that have intended to contribute with the debate of the problems of the mathematical infinite in their potential-actual duality (Fischbein, Tirosh & Hess (1979), Sierspinska (1987), Tall (1980), Tirosh, (1991), Moreno & Waldegg (1991), Tsamir & Tirosh, (1994), D' Amore (1997), Tall (2001), Fischbein, 2001) that generates the influence of the representations and different mathematical languages on the perceptions of the infinite and mathematical reasoning associates, and in the weaknesses and inconsistencies of the student¿s answers to problems in which infinite processes are present.Les idées, résultats et pensées que nous exposons sont produit des études et sont partie des recherches (Garbin 2000, 2003, 2005 et Garbin et Azcárate, 2001) qui ont essayé de répondre au débat de la problématique de l'infini mathématique dans sa dualité potentiel-actuel (Fischbein, Tirosh et Hess (1979), Sierspinska (1987), Tall (1980), Tirosh, (1991), Moreno et Waldegg (1991), Tsamir et Tirosh, (1994), D'Amore (1997), Tall (2001), Fischbein 2001), du point de vue spécifique, qui génère l'influence des représentations et des langages mathématiques différentes sur les perceptions de l'infini et raisonnements mathématiques associés, et dans les incohérences des réponses des étudiants aux problèmes qui incluent l'infini. Cet article est écrit comme partie de la Relme 18 (Réunion Latino-américaine des Mathématiques Pédagogiques qui a eu lieu a Chiapas, Mexique, juillet 2004).As ideais, resultados e reflexões que desenvolvemos, são produtos de estudos e parte de investigações (Garbin 2000, 2003, 2005 e Garbin e Azcárate, 2001) que hão pretendido contribuir com o debate da problemática do infinito matemático na sua dualidade potencial - atual (Fischbein, Tirosh e Hess (1979), Sierspinska (1987), Tall (1980), Tirosh, (1991), Moreno e Waldegg (1991), Tsamir e Tirosh, (1994), D¿Amore (1997), Tall (2001), Fischbein, 2001), desde a especifica, que gera a influência das representações e distintas linguagens matemáticas sobre as percepções do infinito e raciocínios matemáticos associados, e nas inconsistências e incoerências das respostas dos alunos a problemas que estão presentes processos infinitos. Este escrito foi desenvolvido como curso: corso na Relme 18 (Reunión Latinoamericana de Matemática Educativa realizada en Chiapas, México, Julio 2004).Las ideas, resultados y reflexiones que desarrollamos, son producto de estudios y parte de investigaciones (Garbin 2000, 2003, 2005 y Garbin y Azcárate, 2001) que han pretendido contribuir con el debate de la problemática del infinito matemático en su dualidad potencial-actual (Fischbein, Tirosh y Hess (1979), Sierspinska (1987), Tall (1980), Tirosh, (1991), Moreno y Waldegg (1991), Tsamir y Tirosh, (1994), D¿Amore (1997), Tall (2001), Fischbein, 2001), desde la específica, que genera la influencia de las representaciones y distintos lenguajes matemáticos sobre las percepciones del infinito y razonamientos matemáticos asociados, y en las inconsistencias e incoherencias de las respuestas de los alumnos a problemas que están presentes procesos infinitos. Este escrito fue desarrollado como curso corto en la Relme 18 (Reunión Latinoamericana de Matemática Educativa realizada en Chiapas, México, Julio 2004)
On phenomenology of remote vision: the panoramas of the first lunar probes
No full textAn examination of the extensive collection of images produced by the probes sent to the Moon and other planets of the solar system during the last decades allows to recognize some recurring forms and characteristics of distant vision. For this purpose a phenomenological and topological approach proves more useful than an exclusively morphological one. First satellites placed in orbit around the Earth, or first probes sent to the Moon by the Soviets, such as Luna 1 and Luna 2, are not equipped to take pictures but are limited to providing data on their position and little more. American probes of Ranger, Surveyor and Orbiter programs transmit to Earth a large number of images of the Moon, taken mainly in three characteristic ways of space shooting: that of the linear sequence, that of the central panorama and that of the orbital mapping. Panorama has become one of the characteristic forms of distant vision. In particular, panoramas obtained from Surveyors’ photos are the first views of non-terrestrial landscapes, and can be considered as an elaborate anticipation of the most recent terrestrial and non terrestrial panoramas, and in particular those of Mars
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
Going 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
EZETIMIBE PROTECTS THP-1 CELLS FROM ISCHEMIA-REPERFUSION INJURY REDUCING OXIDATIVE STRESS AND UP-REGULATING NRF2/ ARE GENE EXPRESSION
No full textBackground and Aims: We demonstrated that physical training, characterized by repeated ischemia-reperfusion (I-R) episodes (ischemic conditioning, IC), protects circulating cells from peripheral artery disease (PAD) patients against ischemic harms by reducing oxidative stress (OS) and by up-regulating nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway expression. Ezetimibe (Eze) has been shown to alleviate OS enhancing Nrf2 nuclear translocation in an AMPK/p62-dependent manner. In a cellular I-R and IC model, we aimed to investigate: 1) the effect of Eze on OS and Nrf2/ARE gene expression 2) whether Eze could have a synergistic effect on IC. Methods: THP-1 cells were treated with or without Eze (50mM) overnight, then subjected to 1 or 6 repetitive I-R cycles using EVOS FL Auto Imaging System. Reactive oxygen species (ROS) formation was evaluated with DCF in cytofluorimetry. Nrf2/ARE and p62 gene expression were evaluated by RT-PCR and western blotting. Results: When THP-1 cells were exposed to 1 I-R cycle, the preincubation with Eze significantly reduced ROS formation (p<0.01) and up-regulated Nrf2/ARE pathway expression and p62 phosphorylation (p<0.001). Multiple I-R cycles, acting as IC, significantly reduced ROS formation and upregulated Nrf2/ARE gene expression (p<0.001); in these conditions, Eze preincubation was able not only to almost abolish ROS formation (p<0.01) but also further up-regulate Nrf2/ARE expression. Conclusions: In our I-R model, Eze not only restores I-R-induced oxidative damages through Nrf2/ARE signaling up-regulation but also has a synergistic effect on IC. This new “pleiotropic” effect, if confirmed in vivo, may strengthen the use of Eze in PAD patien
Genetic and morphological evidences for the existence of a new species of Contracaecum (Nematoda: Anisakidae) parasite of Phalacrocorax brasilianus (Gmelin) from Chile and its genetic relationships with congeners from fish-eating birds.
No full textContracaecum australe n. sp. is described from the Neotropic cormorant Phalacrocorax brasilianus in Chile based on morphology and the sequence analyses of multiple loci, i.e., mitochondrial cytochrome oxidase 2, mtDNA cox-2, the small subunit of the mitochondrial ribosomal RNA gene, rrnS, and the ITS-1 and ITS-2 regions of nuclear ribosomal DNA. Moreover, sequence analysis of the same genes was carried out on the morphospecies Contracaecum chubutensis Garbin et al. (2008) from Phalacrocorax atriceps. Further, genetic relationships are presented between C. australe n. sp. and C. chubutensis with respect to the related congeners from fish-eating birds previously characterized genetically on the same genetic markers, i.e., Contracaecum rudolphii A, B, C, D, and E, Contracaecum septentrionale, Contracaecum microcephalum, Contracaecum bioccai, Contracaecum pelagicum, Contracaecum micropapillatum, Contracaecum gibsoni, and Contracaecum overstreeti. Several phylogenetic analyses (MP, NJ, and BI) inferred from mitochondrial genes (cox-2 , rrnS) were congruent in depicting C. australe n. sp. and C. chubutensis as forming distinct clades, highly supported, from the remainder of the Contracaecum taxa considered; thus, it validates their specific status. Further, analyses of the ITS-1 and ITS-2 sequence data of C. australe n. sp. and C. chubutensis supported their distinction with respect to the 2 sibling species, C. rudolphii D and C. rudolphii E, previously detected from Phalacrocoracidae of Australia. Morphological analysis and the differential diagnosis of male specimens of C. australe n. sp. enabled the detection of differences in a number of characters, including spicule length, peculiar shape of male tail, paracloacal papillae disposition, and shape and bifurcation depth of interlabia. According to the genetic and morphological results obtained, the erection of a new taxon from fish-eating birds of the Austral region is given and its formal description is presented. Phylogenetic trees support both C. australe n. sp. and C. chubutensis as being included in the same clade with the previously detected species from cormorants, i.e., C. rudolphii A, B, C, and C. septentrionale. The finding of C. australe n. sp. and C. chubutensis parasites of Ph. brasilianus and Ph. atriceps, respectively, appears to support a host-parasite association between the C. rudolphii A, B, and C, C. septentrionale, C. chubutensis, and C. australe n. sp. and different species of cormorants belonging to Phalacrocorax
FEM modelling of CFRP strips bond behaviour for bed joints reinforcement technique
No full textThis work presents the main results of a numerical analysis of the local effects connected to the application of the bed reinforcement technique in historic masonry walls. In particular, CFRP thin strips and lime-based mortar are considered, as reinforcing and embedding materials. On the basis of experimental results, a detailed micro-model has been developed. Mechanical characterization of the basic materials and of the local behaviour of the mutual interaction among them allowed defining the main parameters and constitutive laws to adopt in the model. The model is able to describe the bond phenomenon at local level up to the ultimate loads, identifying the chemical bond stress peak ad its migration along the anchorage lengt
Fig. 16. BMNH 39837 in A taxonomic revision of geoemydid turtles from Siwalik-age of India and Pakistan
No full textFig. 16. BMNH 39837, referred to Pangshura flaviventer Günther, 1864 by Lydekker (1885a), here identified as Pangshura sp. A. Photograph of carapace. B. Illustration of carapace. C. Photograph of plastron. D. Illustration of plastron. Scale bar: 3 cm.Published as part of Garbin, Rafaella C., Bandyopadhyay, Saswati & Joyce, Walter G., 2020, A taxonomic revision of geoemydid turtles from Siwalik-age of India and Pakistan, pp. 1-67 in European Journal of Taxonomy 652 on page 24, DOI: 10.5852/ejt.2020.652, http://zenodo.org/record/386023
"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.
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