665 research outputs found

    Severe rhabdomyolysis associated with pemetrexed-based chemotherapy

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    Pemetrexed is an antifolate metabolite that inhibits several enzymes involved in the folate pathway. It has activity against various solid tumours, and has been approved for treatment of malignant pleural mesothelioma on the basis of findings from a randomised phase III trial.1 The main toxic effects noted for pemetrexed have been rash, myelosuppression, diarrhoea, mucositis, and reversible elevation of liver enzymes—effects that are preventable partly by vitamin supplementation.

    Unsteady Simulation of CO/H2/N2/air Turbulent Non-Premixed Flame

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    The Sandia/ETH-Zurich CO/H2/N2 non-premixed unconfined turbulent jet flame (named ‘Flame A’) is numerically simulated by solving the unsteady compressible reactive Navier– Stokes equations in a three-dimensional axisymmetric formulation, hence, in a formally twodimensional domain. The turbulent combustion closure model adopted is the Fractal Model, FM, developed as a subgrid scale model for Large Eddy Simulation. The fuel is injected from a straight circular tube and the corresponding Reynolds number is 16 700, while the air coflows. Since the thickness of the nozzle is 0.88 mm, and the injection velocity high, ?104ms?1, capturing the stabilization mechanism of the actual flame requires high spatial resolution close to the injector. Results are first obtained on a coarse grid assuming a fast-chemistry approach for hydrogen oxidation and a single step mechanism for carbon monoxide oxidation.With this approach the flame is inevitably anchored. Then, to understand the actual flame stabilization a more complex chemical mechanism, including main radical species, is adopted. Since using this chemistry and the coarse grid of previous simulation the flame blows off numerically, attention is focused on understanding the actual flame stabilization mechanism by simulating a small spatial region close to the injection with a very fine grid. Then, analysing these results, an artificial anchoring mechanism is developed to be used in simulations of the whole flame with a coarse grid. Unsteady characteristics are shown and some averaged radial profiles for temperature and species are compared with experimental data

    Effect of coil charge duration on combustion variability and flame morphology in a GDI engine working in lean burn conditions

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    Spark ignition (SI) and subsequent flame front development exert a significant influence on cyclic variability of internal combustion engines (ICEs). The increasing exploitation of lean air-fuel mixtures in SI engines to lower fuel consumption and CO2 emissions is driving the scientific community towards the search for innovative combustion strategies. Moreover, although lean combustion has been widely investigated and an important number of studies is already present in literature, the high cyclic variability typical of this combustion process still represents a major hinder to its exploitation. This study aims to investigate the effects of increasing ignition energy on combustion characteristics of lean mixtures. Tests were performed on an optically accessible gasoline direct injection (GDI) engine that allowed to investigate the correlation between the thermodynamic results and spark arc-flame morphology. Engine speed was fixed at 2000 rpm, a relative air fuel ratio (AFRrel) of about 1.3 was selected and ignition timing was set at 12 crank angle degrees (CAD) bTDC. Coil charge duration was swept from 10 to 40 CAD. Two intake pressure levels were investigated, the first corresponding to wide open throttle under naturally aspirated operating mode, the second with an intake pressure of 1.2 bar, thus corresponding to a boosted operating condition. Two dedicated scripts built using NI Vision were employed for image processing, allowing the evaluation of temporal and spatial evolution of the early stages of combustion. Arc elongation and flame front contour were used as correlation parameters that characterize flame kernel inception and development. The results confirm that, as expected, the increase of the coil charge duration tends to reduce cyclic variability in terms of engine output. The optical investigations revealed that for both examined cases the standard deviation related to the wrinkling effect on flame edge at CA5 decreased as the coil charge duration increased

    Prestimulus EEG power predicts conscious awareness but not objective visual performance

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    Prestimulus oscillatory neural activity has been linked to perceptual outcomes during performance of psychophysical detection and discrimination tasks. Specifically, the power and phase of low frequency oscillations have been found to predict whether an upcoming weak visual target will be detected or not. However, the mechanisms by which baseline oscillatory activity influences perception remain unclear. Recent studies suggest that the frequently reported negative relationship between power and stimulus detection may be explained by changes in detection criterion (i.e., increased target present responses regardless of whether the target was present/absent) driven by the state of neural excitability, rather than changes in visual sensitivity (i.e., more veridical percepts). Here, we recorded EEG while human participants performed a luminance discrimination task on perithreshold stimuli in combination with single-trial ratings of perceptual awareness. Our aim was to investigate whether the power and/or phase of prestimulus oscillatory activity predict discrimination accuracy and/or perceptual awareness on a trial-by-trial basis. Prestimulus power (3–28 Hz) was inversely related to perceptual awareness ratings (i.e., higher ratings in states of low prestimulus power/high excitability) but did not predict discrimination accuracy. In contrast, prestimulus oscillatory phase did not predict awareness ratings or accuracy in any frequency band. These results provide evidence that prestimulus power influences the level of subjective awareness of threshold visual stimuli but does not influence visual sensitivity when a decision has to be made regarding stimulus features. Hence, we find a clear dissociation between the influence of ongoing neural activity on conscious awareness and objective performance

    Year-round variation in the isotopic niche of Scopoli's shearwater (Calonectris diomedea) breeding in contrasting sea regions of the Mediterranean Sea

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    Top marine predators are key components of marine food webs. Among them, long-distance migratory seabirds, which travel across different marine ecosystems over the year, may experience important year-round changes in terms of oceanographic conditions and availability of trophic resources. We tested whether this was the case in the Scopoli's shearwater (Calonectris diomedea), a trans-equatorial migrant and top predator, by sampling birds breeding in three environmentally different regions of the Mediterranean Sea. The analysis of positional data and stable isotopes (δ1³C and δ15N) of target feathers revealed that birds from the three regions were spatially segregated during the breeding period while they shared non-breeding areas in the Atlantic Ocean. Isotopic baseline levels of N and C (meso-zooplankton) were significantly different among marine regions during breeding. Such variation was reflected at the higher trophic levels of pelagic and demersal fish muscles as well as in shearwater feathers grown in the Mediterranean. δ15N- and δ13C-adjusted values of shearwaters were significantly different among populations suggesting that birds from different breeding areas relied on prey species from different trophic levels. Conversely, the non-breeding spatial and isotopic niches overlapped greatly among the three populations. Shearwater trophic niches during breeding were narrower and segregated compared to the non-breeding period, revealing a high plasticity in trophic resource use. Overall, this study highlights seasonal and region-specific use of trophic resources by Scopoli's shearwater, suggesting a broad trophic plasticity and possibly a high adaptability to environmental changes

    Long-term data prove useful to keep track of non-indigenous seaweed fate

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    The Mar Piccolo of Taranto (southern Italy, Mediterranean Sea), a site of the European LTER network, is a transitional water system, where a century-old intensive mussel farming activity has been carried out, together with an intense import-export business of bivalve mollusks. Previous studies showed that this basinisthirdforNISseaweedintroductionintheMediterraneanSea,aftertheThau LagoonandtheVeniceLagoon.Thepresentpaperdealswiththeresultsof11-year monitoring activity on non-indigenous species (NIS) of seaweeds, which was performed in the Mar Piccolo. In the studied period (2011–2021), two different time frames (i.e., 2011–2015 and 2016–2021) were considered, since they were based on a different number of sampling sites. To investigate spatial and temporal differences in the seaweed assemblage, a multivariate analysis was performed considering the NIS and the most important native species in terms of temporal occurrence. Fourteen NIS were recorded in total in the Mar Piccolo of Taranto duringthisperiod,withvariableabundancesamongsitesandyears:ninespeciesin the firsttimeperiod,andthirteenspeciesinthesecondone.Caulerpacylindracea, recorded with negligible biomass in the first period, was absent in the secondperiod samplings. Molecular analyses confirmed the taxonomy of three species (i.e., Grateloupia minima, Neopyropia koreana, and Polysiphonia morrowii), previously identified only through morphological features. The most abundant specieswasHypneacorona,whichalmostdoubleditsbiomassinthesecondtime period compared to the first one. Three species (i.e., Caulacanthus okamurae, G. minima, and P. morrowii) increased their biomass by an order of magnitude in the second time period. No significant differences were found over years. Site 1 resulted in significant differences among the sites and different seasonal pattern occurred among the investigated sites. No significant long-term changes occurred in the seaweed assemblages, suggesting the absence of strong disturbances due to the settlement of NIS

    Inter-individual differences in foraging tactics of a colonial raptor : consistency, weather effects, and fitness correlates

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    Background: Consistent inter-individual differences in behavioural phenotypes may entail differences in energy efficiency and expenditure, with different fitness payoffs. In colonial-breeding species, inter-individual differences in foraging behaviour may evolve to reduce resource use overlap among conspecifics exploiting shared foraging areas. Furthermore, individual differences in foraging behaviour may covary with individual characteristics, such as sex or physiological conditions. Methods: We investigated individual differences in foraging tactics of a colonial raptor, the lesser kestrel (Falco naumanni). We tracked foraging trips of breeding individuals using miniaturized biologgers. We classified behaviours from GPS data and identified tactics at the foraging trip level by cluster analysis. We then estimated energy expenditure associated to each tactic from tri-axial accelerometer data. Results: We obtained 489 foraging trips by 36 individuals. Two clusters of trips were identified, one (SF) characterized by more static foraging behaviour and the other (DF) by more dynamic foraging behaviour, with a higher proportion of flying activity and a higher energy expenditure compared to SF. Lesser kestrels showed consistent inter-individual differences in foraging tactics across weather condition gradients, favouring DF trips as solar radiation and crosswind intensity increased. DF trips were more frequent during the nestling-rearing than during the egg incubation stage. Nestlings whose tracked parent was more prone to perform DF trips experienced higher daily mass increase, irrespective of nestling feeding rates. Conclusions: Our study provided evidence that breeding lesser kestrels flexibly adopted different foraging tactics according to contingent weather landscapes, with birds showing consistent inter-individual differences in the tendency to adopt a given tactic. The positive correlation between the tendency to perform more energy-demanding DF trips and nestling growth suggests that individual differences in foraging behaviour may play a role in maintaining key life-history trade-offs between reproduction and self-maintenance

    The INGV Mobile Telemetered Network (Re.Mo.Tel.): long-term monitoring analysis.

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    Since 2008, the Istituto Nazionale di Geofisica e Vulcanologia (INGV) developed a temporary real-time telemetered seismic network infrastructure (Re.Mo.Tel.) to densify the Italian National Seismic Network in epicentral area, thus improving the location of the aftershocks distribution after a mainshock. This infrastructure consists of various mobile and autonomous seismic stations that in group of three are telemetered to a Very Small Aperture Terminal (VSAT). Using a dedicated bandwidth on UHF, Wi-Fi and satellite frequency, the system is able to stream real-time data to the INGV acquisition centers in Rome and Grottaminarda. The deployment of the seismic network is supported by a geographical information system (GIS) that visualizes, for the epicentral area, information about instrumental seismicity, seismic risk, macroseismic felts and territorial data. The April, 6th, 2009 Mw 6.3 L'Aquila destructive earthquake represented the first real-case where the entire Re.Mo.Tel. infrastructure has been deployed. Less than 6 hours after the earthquake occurrence, a first accelerometric station was streaming data to the INGV seismic monitoring headquarters. A total number of 9 seismic stations was installed within 4 days after the main event, with the aim of recording continuous data to contribute in the aftershocks detection. In detail the first day a number of 3 stations was installed, surrounding the mainshock. Then the rest of the stations was deployed on the third and the fourth day to the south and the north, following the post-seismic evolution. A project funded by the Dipartimento di Protezione Civile (DPC-Civil Defense) gave the opportunity to maintain some of the deployed stations throughout the duration of the project of one year (although the stations are still installed) to assure the long-term monitoring of the triggered seismic sequence. In this work, we investigate: • The impact of the Re.Mo.Tel. on earthquakes detection and real-time monitoring of the sequence evolution; • The location improvement due to the deployment of stations closer to the epicentral area (with installations that followed the early evolution and complexity of fault fractures); • The network reliability in terms of data stored throughout the working period

    Factors Affecting Infestation by Triatoma infestans in a Rural Area of the Humid Chaco in Argentina: A Multi-Model Inference Approach

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    Vector-borne transmission of Chagas disease remains a major public health problem in parts of Latin America. Triatoma infestans is the main vector in the countries located in the South American Cone, particularly in the Gran Chaco ecoregion where residual insecticide control has achieved only a moderate, irregular impact. To contribute to improved control strategies, we analyzed the factors associated with the presence and abundance of T. infestans in 327 inhabited houses in a well-defined rural area with no recent vector control interventions in the humid Argentine Chaco. Bugs were found mainly in domiciles, kitchens, storerooms, and chicken coops and nests, particularly where adequate refuge and animal hosts (humans, dogs, cats or poultry) were available. Domiciles constructed from mud were the most often infested, but brick-and-cement domiciles, even in good conditions, were also found infested. Availability of refuge and hosts for T. infestans are key targets for vector control. Ten-fold variations in domestic infestation observed across neighboring villages, and differences in the relevant factors for T. infestans presence with respect to other areas of the Gran Chaco region suggest that host management, building techniques and insecticide use need to be tailored to the local environment, socio-economic characteristics, and climatic conditions

    Seismic activity in the Pollino region (Basilicata-Calabria border)

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    The Pollino region and the whole Calabria-Lucania border are known for the absence of destructive (M>6) historical earthquakes. This lack of historical seismicity is noticeable in the analysis of Southern Apennines and Calabria earthquake history (Rovida et al., 2011). At the same time, paleoseismological studies found evidence for significant active faulting (Cinti et al., 1997; Michetti et al., 1997) pointing to the Pollino area as a seismic gap. Instrumental seismicity in the region is characterized by the occurrence of seismic sequences, one of the most significant in the last decades is the Mercure seismic sequence, Mw 5.6 in September 1998 (Brozzetti et al., 2008). For this reason, the sequence started in 2010 raised a big concern in the population and local authorities. INGV is following the evolution of the sequence since its beginning, in March 2010, increasing the seismic monitoring and planning several activities and projects. The area was proposed by INGV to DPC (Dipartimento di Protezione Civile nazionale) for inclusion in the projects to be carried out in the present INGV-DPC agreement. This project has just started and will try to provide better constraints to the active tectonics and fault identification of the region. In this paper we describe what INGV is doing to understand better the tectonics of the region using microseismicity, and try to offer some cue to the discussion about the seismogenic faults in the area.Published5-92T. Tettonica attivaN/A or not JCRope
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