Search results for "Vertical"

Palaeogeographical evolution of the Egadi Islands (western Sicily, Italy). Implications for late Pleistocene and early Holocene sea crossings by huma…

2019

Abstract The continental shelf morphology offshore of western Sicily suggests that during the Last Glacial Maximum (LGM, 20 ka cal BP), two of the Egadi Islands, Favignana and Levanzo, were connected to Sicily by a wide emerged plain, while Marettimo was only separated from the other islands by a narrow channel. We studied the relative sea-level variation from the LGM until today, focussing on two important time slices: the Mesolithic (9.5–13 ka cal BP) and the Neolithic (6.5–7.5 ka cal BP). In this research, we discuss a sea-level rise model by means of geomorphological, archaeological and geophysical observations and new radiocarbon dating of marine and terrestrial fossil fauna. The resul…

A comparison of HONO budgets for two measurement heights at a field station within the boreal forest in Finland

2015

Atmospheric concentrations of nitrous acid (HONO), one of the major precursors of the hydroxyl radical (OH) in the troposphere, significantly exceed the values predicted by the assumption of a photostationary state (PSS) during daytime. Therefore, additional sources of HONO were intensively investigated in the last decades. This study presents budget calculations of HONO based on simultaneous measurements of all relevant species, including HONO and OH at two different measurement heights, i.e. 1 m above the ground and about 2 to 3 m above the canopy (24 m above the ground), conducted in a boreal forest environment. We observed mean HONO concentrations of about 6.5 × 108 molecules cm−3 (26 p…

Congenital \textittoxoplasma infection: monthly prenatal screening decreases transmission rate and improves clinical outcome at age 3 years

2013

Background. Toxoplasma infection during pregnancy exposes the fetus to risks of congenital infection and sequelae that depend heavily on gestational age (GA) at time of infection. Accurate risk estimates by GA are necessary to counsel parents and improve clinical decisions. Methods. We analyzed data from pregnant women diagnosed with acute Toxoplasma infection in Lyon (France) from 1987 to 2008 and assessed how the risks of congenital toxoplasmosis and of clinical signs at age 3 years vary depending on GA at the time of maternal infection. Results. Among 2048 mother-infant pairs, 93.2% of mothers received prenatal treatment and 513 (24.7%) fetuses were infected. Because of a significant red…

Differential effects of vertical and horizontal transmission in the fitness of an RNA virus: A reanalysis

2002

Cooperation and conflict in host manipulation: interactions among macro-parasites and micro-organisms.

2014

10 pages; International audience; Several parasite species are known to manipulate the phenotype of their hosts in ways that enhance their own transmission. Co-occurrence of manipulative parasites, belonging to the same species or to more than one species, in a single host has been regularly observed. Little is known, however, on interactions between co-occurring manipulative parasites with same or different transmission routes. Several models addressing this problem have provided predictions on how cooperation and conflict between parasites could emerge from multiple infections. Here, we review the empirical evidence in favor of the existence of synergistic or antagonistic interactions bet…

Transmission bottlenecks and the evolution of fitness in rapidly evolving RNA viruses

2003

We explored the evolutionary importance of two factors in the adaptation of RNA viruses to their cellular hosts, size of viral inoculum used to initiate a new infection, and mode of transmission (horizontal versus vertical). Transmission bottlenecks should occur in natural populations of viruses and their profound effects on viral adaptation have been previously documented. However, the role of transmission mode has not received the same attention. Here we used a factorial experimental design to test the combined effects of inoculum (bottleneck) size and mode of transmission in evolution of vesicular stomatitis virus (VSV) in tissue culture, and compared our results to the predictions of a …

Evaluating European railway deregulation using different approaches

2012

Abstract There has recently been a great deal of interest in the impacts of the deregulating and restructuring measures in the European railway sector. A vast amount of literature is devoted to analyzing the effects of these deregulation and restructuring measures on efficiency and productivity and the results are not totally unambiguous. However, while most of the papers show that the introduction of competition within the sector (in both passenger and freight markets) has had a positive impact in terms of efficiency and productivity, the impact of vertical separation has produced different results in the literature. The contribution of this paper to the existing literature is twofold. Fir…

Offshoring along the production chain

2009

Recent contributions on offshoring often assume that firms can freely split their production process into separate steps which can be ranked according to the cost savings from producing abroad. We replace this assumption by the notion of a technologically determined sequence of production steps. In our model, cost savings from offshoring fluctuate along the production chain, and moving unfinished goods across borders causes transport costs. We show that, in such a setting, firms may refrain from offshoring even if relocating individual steps would be advantageous in terms of offshoring costs, or they may offshore (almost) the entire production chain to save transport costs. Small variations…

Guión para la intervención en el "Fórum Cultural Mundial" de la Sra. Ministra de Cultura

2004

Como indica el propio título, se trata de un texto escrito por José Vidal-Beneyto para la Ministra de Cultura en el contexto del "Fórum Universal de las Culturas 2004", celebrado en Barcelona entre el 9 de mayo y el 26 de septiembre de ese año.

Validity and reliability of a 3-axis accelerometer for measuring weightlifting movements

2016

The purpose of the current study was to assess the validity and reliability of measures obtained by a 3-axis commercial accelerometer during weightlifting movements in comparison with kinematic data derived from the 3D videography. Kinematic data from 3D videography were obtained from 11 track & field throwers performing 3 trials each one at different loads in power snatch, power clean and jerk from the rack. The results showed that the accelerometer measures were highly correlated with derived acceleration data from 3D videography data in the vertical plane (Z axis) taking up to the pull phase (including first pull, transition and second pull) for power snatch and power clean and up t…