Search results for "MACRO"
showing 10 items of 3471 documents
Modeling, evaluation, and scale on artificial pedestrians: a literature review
2017
Modeling pedestrian dynamics and their implementation in a computer are challenging and important issues in the knowledge areas of transportation and computer simulation. The aim of this article is to provide a bibliographic outlook so that the reader may have quick access to the most relevant works related to this problem. We have used three main axes to organize the article's contents: pedestrian models, validation techniques, and multiscale approaches. The backbone of this work is the classification of existing pedestrian models; we have organized the works in the literature under five categories, according to the techniques used for implementing the operational level in each pedestrian …
A macroeconomic analysis of the farmland value determinants in Italy
2013
The determinants of farmland value and the factors that have caused its changes over time have been discussed extensively in the economic literature. This studies offer different classifications of the determinants of the farmland value. The aim of this paper is to investigate the influence on the farmland value of the some macro-economic variables related to the agricultural sector both directly and indirectly. A multiple regression model is adopted to answer the research questions. The results showed, on the one hand, a strong influence of agricultural productivity, a regional expenditure allocated to the sector and an increasing diffusion in the regions of protected areas on the farmland…
Experimental Study on the Diet of Mosquitofish (Gambusia holbrooki) under Different Ecological Conditions in a Shallow Lake
2004
We studied the diet of the eastern mosquitofish Gambusia holbrooki with in situ experimental mesocosms located in a shallow lake. Different nutrient concentrations (phosphorus and nitrogen) and fish population densities were tested. Our results confirm that it is a planktivorous species, with also a great ingestion of algae and detritus. Nutrient fertilization caused almost no changes in this species feeding behavior, but larger mosquitofish stocks induced a shift to zooplanktivory and a decline in detritivory. When macrophytes were present, the predation effect focused on zooplankton and plant-associated animals, otherwise predation on bottom macroinvertebrates increased. Females preyed up…
Microcephaly and macrocephaly. A study on anthropometric and clinical data from 308 subjects
2019
Head circumference is the auxological parameter that most correlates with developmental anomalies in childhood. Head circumference (HC) two standard deviations (SD) below or above the mean defines microcephaly and macrocephaly, respectively. The aim of this retrospective study was to explore anthropometric parameters and clinical characteristics among subjects with abnormalities in HC who had been referred for developmental assessment. One hundred and sixty four subjects with microcephaly and 144 subjects with macrocephaly were enrolled from birth to 18 months of age. Head circumference at birth and the association with variables related to maternal health status, gestational age, growth pa…
Biodiversidad y ecología de metacomunidades de macroinvertebrados acuáticos de las malladas de la Devesa y del Racó de l'Olla (PN de l'Albufera de Va…
2015
Las malladas de la Devesa y del Racó de l’Olla se sitúan sobre la restinga dunar que separa el lago de l’Albufera y el mar Mediterráneo. Se trata de casi un centenar de encharcamientos temporales o permanentes que se distribuyen sobre una superficie de poco más de 600 ha. En los años 1970-80 estuvieron a punto de desaparecer bajo una fuerte presión urbanística. Tienen una gran importancia como reducto de fauna y flora al ser un hábitat poco común, y por ello posee diferentes figuras de protección dentro del entorno del Parque Natural de l’Albufera. El presente trabajo versa sobre diferentes aspectos de la biodiversidad y ecología de los invertebrados acuáticos de las malladas. Durante los a…
GW170817: Measurements of Neutron Star Radii and Equation of State
2018
On 17 August 2017, the LIGO and Virgo observatories made the first direct detection of gravitational waves from the coalescence of a neutron star binary system. The detection of this gravitational-wave signal, GW170817, offers a novel opportunity to directly probe the properties of matter at the extreme conditions found in the interior of these stars. The initial, minimal-assumption analysis of the LIGO and Virgo data placed constraints on the tidal effects of the coalescing bodies, which were then translated to constraints on neutron star radii. Here, we expand upon previous analyses by working under the hypothesis that both bodies were neutron stars that are described by the same equation…
POLYASPARTAMIDE-POLYLACTIDE GRAFT COPOLYMERS WITH TUNABLE PROPERTIES FOR THE REALIZATION OF FLUORESCENT NANOPARTICLES FOR IMAGING
2015
Here, the synthesis and the characterization of novel amphiphilic graft copolymers with tunable properties, useful in obtaining polymeric fluorescent nanoparticles for application in imaging, are described. These copolymers are obtained by chemical conjugation of rhodamine B (RhB) moieties, polylactic acid (PLA), and O-(2-aminoethyl)-O'-methyl poly(ethylene glycol) (PEG) on α,β-poly(N-2-hydroxyethyl)-D,L-aspartamide (PHEA). In particular, PHEA is first functionalized with RhB to obtain PHEA-RhB with a derivatization degree in RhB (DDRhB ) equal to 0.55 mol%. By varying the reaction conditions, different amounts of PLA are grafted on PHEA-RhB to obtain PHEA-RhB-PLA with DDPLA equal to 1.9, 4…
Pneumocisternographic exploration of the posterior fossa
1958
A method previously proposed by the Author for the pneumographic visualization of the posterior fossa has been utilized for the study of several cases. Of these some are reported in this paper. The indications and the advantages of the method are discussed.
Pressure-induced phase transformations in mineral chalcocite, Cu2S, under hydrostatic conditions
2014
Abstract High-pressure room-temperature angle-dispersive powder X-ray diffraction measurements on Cu2S chalcocite were performed up to 30 GPa using a diamond-anvil cell, He as pressure transmitting medium and synchrotron radiation. Two first-order phase transitions were found at 3.2 and 7.4 GPa. The indexation of the powder diffraction patterns suggests three different monoclinic cells for the low-pressure chalcocite and the two high-pressure phases. Subtle changes in the X-ray diffraction patterns suggest a third pressure-induced transition above 26 GPa. Structural parameters and compressibility are discussed and compared to those reported in a previous study on Cu2S nanowires.
AB$$_{2}$$O$$_{4}$$ Compounds at High Pressures
2014
In this chapter, we present an overview of the effects of pressure on the crystalline structure and physical properties of oxygen-based spinels and other related oxides. Recent X-ray diffraction and Raman spectroscopy studies are summarized. A brief description of pressure-driven transitions and post-spinel structures is also provided. We also compare the response to high-pressure of several spinel oxides. We conclude with an examination of elastic and magnetic properties.