297 research outputs found
Assisted Code Point Positioning at Sub-meter Accuracy Level with Ionospheric Corrections Estimated in a Local GNSS Permanent Network
No full textIt is well know that GNSS permanent networks for real-time positioning with stations spaced at few tens of kilometers in the average were mainly designed to generate and transmit products for RTK (or Network-RTK) positioning. In this context, RTK products are restricted to users equipped with geodetic-class receivers which are continuously linked to the network processing center through Internet plus mobile phone. This work is a first step toward using a local network of permanent GNSS stations to generate and make available products devoted to ionospheric delay correction that could remarkably improve positioning accuracy for C/A receiver users, without forcing them to keep a continuous link with the network. A simple experiment was carried out based on data from the RESNAP-GPS network (w3.uniroma1.it/resnap-gps), located in the Lazio Region (Central Italy) and managed by DITS-Area di Geodesia e Geomatica, University of Rome "Sapienza". C/A raw observations were processed with Bernese 5.0 CODSPP module (single point positioning based on code measurements) using IGS precise ephemeris and clocks. Further, the RINEX files were corrected for the Differential Code Biases (DCBs) according to IGS recommendations. One position per epoch (every 30 s) was estimated from C/A code; the vertical coordinate errors showed a typical signature due to the ionospheric activity: higher errors for day-time (up to 5 m) and smaller ones for night-time (around 1.5 m). In order to improve the accuracy of the solution, ionospheric corrections were estimated using the La Plata Ionospheric Model, based on the dual-frequency observations from the RESNAP-GPS network. This procedure allowed to reduce horizontal and vertical errors within 0.5 m (CE95) and 1 m (LE95) respectively. Finally, the possibility to predict the ionospheric model for few hours was preliminary checked. Our approach shows the possibility of a novel use of the measurements collected by GNSS permanent networks designed for real-time positioning services, which can assist and remarkably improve the C/A code real-time positioning supplying off-line predicted ionospheric corrections, acting as a local Ground Based Augmentation System
Pseudorange single point positioning con accuratezza submetrica per mezzo di correzioni ionosferiche basate su reti di stazioni permanenti
No full textComparison of anti-inflammatory mechanisms between doxofylline and theophylline in human monocytes
No full textMethylxanthines are important pharmacological agents in the treatment of asthma and of chronic obstructive pulmonary diseases. The present study was designed to compare the ability of doxofylline and theophylline to modulate inflammatory pathways in human monocytes
Geodetic Reference Frame for the Americas
No full textSIRGAS (an acronym of the Spanish term for ‘Geocentric Reference System for the Americas’) is an international organisation under the umbrella of the International Association of Geodesy (IAG) and the Pan-American Institute of Geography and History (PAIGH). Its main objective is the defi nition, realisation and maintenance of a state-of-the-art geodetic reference frame in Latin America and the Caribbean. This reference frame must support both highly demanding scientifi c studies and the development of a Spatial Data Infrastructure for the Americas. More than 50 institutions from 19 countries, including the national mapping agencies of Latin America, are committed to SIRGAS in a voluntary partnership.Fil: Brunini, Claudio Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; ArgentinaFil: Sánchez, Laura. SIRGAS; Alemani
The role of monocytes in ANCA-associated vasculitides
No full textThe anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitides (AAV) are a heterogeneous group of diseases causing inflammation in small blood vessels and linked by the presence of circulating ANCA specific for proteinase 3 (PR3) or myeloperoxidase (MPO). These antigens are present both in the cytoplasmic granules and on the surface of neutrophils, and the effect of ANCA on neutrophil biology has been extensively studied. In contrast, less attention has been paid to the role of monocytes in AAV. These cells contain PR3 and MPO in lysosomes and can also express them at the cell surface. Monocytes respond to ANCA by producing pro-inflammatory and chemotactic cytokines, reactive-oxygen-species and by up-regulating CD14. Moreover, soluble and cell surface markers of monocyte activation are raised in AAV patients, suggesting an activated phenotype that may persist even during disease remission. The presence of monocyte-derived macrophages and giant cells within damaged renal and vascular tissue in AAV also attests to their role in pathogenesis. In particular, their presence in the tertiary lymphoid organ-like granulomas of AAV patients may generate an environment predisposed to maintaining autoimmunity. Here we discuss the evidence for a pathogenic role of monocytes in AAV, their role in granuloma formation and tissue damage, and their potential to both direct and maintain autoimmunity. ANCA-activation of monocytes may therefore provide an explanation for the relapsing–remitting course of disease and its links with infections. Monocytes may thus represent a promising target for the treatment of this group of life-threatening diseases
Adaptation of bean (Phaseolus vulgaris L.) to water deficit.
No full textMade available in DSpace on 2011-06-06T16:56:33Z (GMT). No. of bitstreams: 1
BIC199302.pdf: 72155 bytes, checksum: 7c6a4fb6911415377e6acf339a76b219 (MD5)
Previous issue date: 1994-06-1
Diferential root density and water extraction rate of bean (Phaseolus vulgaris L.) drought-sensitive and tolerant cultivars.
No full textMade available in DSpace on 2011-06-06T16:56:32Z (GMT). No. of bitstreams: 1
BIC199303.pdf: 55799 bytes, checksum: 1a4ccb42b2376e75c8b82bc2ebce67ac (MD5)
Previous issue date: 1994-06-1
The existence of a planet beyond 50 au and the orbital distribution of the classical Edgeworth–Kuiper-Belt objects
No full textWe study the effects of a Mars-like planetoid with a semimajor axis at about ∼60 AU orbiting embedded in the primordial Edgeworth–Kuiper belt (EKB). The origin of such an object can be explained in the framework of our current understanding of the origin of the outer Solar System, and a scenario for the orbital transport mechanism to its present location is given. The existence of such an object would produce a gap in the EKB distribution with an edge at about 50 AU, which seems to be in agreement with the most recent observations. No object at low eccentricity with semimajor axis beyond 50 AU has been detected so far, even though the present observing capabilities would allow an eventual detection (B. Gladman et al. 1998, Astron. J. 116, 2042–2054; D. Jewitt et al. 1998, Astron. J. 115, 2125–2135; E. I. Chiang and M. E. Brown 1999, Astron. J. 118, 1411–1422; R. L. Allen et al. 2000, Astrophys. J. 549, 241–244; C. A. Trujillo et al. 2001, Astron. J. 122, 457–473; B. Gladman et al. 2001, Astron. J. 122, 1051–1066; C. A. Trujillo and M. E. Brown 2001, Astrophys. J. 554, 95–98). Finally, ranges for the magnitude and proper motion of the proposed object are given.Fil: Brunini, Adrian. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Melita, Mario Daniel. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. City University of London; Reino Unid
Adaptação do feijoeiro comum (Phaseolus vulgaris L.) à seca.
No full textRealizou-se este trabalho tendo em vista o propósito de se estudar a adaptação de genótipos de feijoeiro comum (Phaseolus vulgaris L.) à seca, como suporte a programas de melhoramento que visem à criação de cultivares para regiões sujeitas a deficiência hídrica, mediante a avaliação do potencial da água nas folhas e da resistência difusiva estomática. Adicionalmente avaliou-se a técnica de medição da temperatura do dossel pela termometria de infravermelho para inferir o estado hídrico da planta. Os genótipos Carioca e RAB 96 foram submetidos, dos 20 dias após a emergência até a colheita, a dois tratamentos hídricos: irrigação adequada e com deficiência hídrica. Em geral, a cultivar Carioca manteve potenciais de água na folha mais altos e também melhor capacidade de recuperação hídrica, além de apresentar resistência difusiva estomática e temperatura do dossel mais baixas que a linhagem RAB 96 sendo, portanto, melhor adaptada à seca. A temperatura do dossel correlacionou-se significativamente com o potencial da água nas folhas e, devido a sua medição ser rápida e não-destrutiva, mostrou tratar-se de uma técnica útil no processo de seleção de genótipos para regiões sujeitas a deficiência hídrica
Adaptação do feijoeiro (Phaseolus vulgaris L.) à seca. I. Densidade e eficiência radicular.
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