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Context. Galactic cosmic rays (GCRs) and solar particles with energies greater than tens of MeV penetrate spacecraft and instruments hosted aboard space missions. The Solar Orbiter Metis coronagraph is aimed at observing the solar corona in both visible (VL) and ultraviolet (UV) light. Particle tracks are observed in the Metis images of the corona. An algorithm has been implemented in the Metis processing electronics to detect the VL image pixels crossed by cosmic rays. This algorithm was initially enabled for the VL instrument only, since the process of separating the particle tracks in the UV images has proven to be very challenging. Aims. We study the impact of the overall bulk of particles of galactic and solar origin on the Metis coronagraph images. We discuss the effects of the increasing solar activity after the Solar Orbiter mission launch on the secondary particle production in the spacecraft. Methods. We compared Monte Carlo simulations of GCRs crossing or interacting in the Metis VL CMOS sensor to observations gathered in 2020 and 2022. We also evaluated the impact of solar energetic particle events of different intensities on the Metis images. Results. The study of the role of abundant and rare cosmic rays in firing pixels in the Metis VL images of the corona allows us to estimate the efficiency of the algorithm applied for cosmic-ray track removal from the images and to demonstrate that the instrument performance had remained unchanged during the first two years of the Solar Orbiter operations. The outcome of this work can be used to estimate the Solar Orbiter instrument's deep charging and the order of magnitude for energetic particles crossing the images of Metis and other instruments such as STIX and EUI. [ABSTRACT FROM AUTHOR]

Context. The Metis coronagraph is one of the remote sensing instruments of the ESA-NASA Solar Orbiter mission. The goal for the instrument is to enable the study of the solar atmosphere and solar wind by simultaneously acquiring images of the solar corona at two different wavelengths: visible light (VL), within a band ranging from 580 nm to 640 nm, and ultraviolet light, in the HI Lyα 121:6 ± 10 nm. The visible-light channel of the coronagraph includes a polarimeter with electro-optically modulating liquid crystal variable retarders to measure the linearly polarized brightness of the K-corona and derive the electron density. Aims. In this paper, we present the first in-flight validation results of the Metis polarimetric channel together with a comparison to the on-ground calibrations. This paper seeks to validate the first use of an electro-optical device, the liquid crystal-based polarimeter, in deep space and within a hard radiation environment. Methods. We used the orientation of the K-corona's linear polarization vector during the roll maneuvers of the Space Orbiter spacecraft for the in-flight calibration. Results. The Metis coronagraph on board the Solar Orbiter shows good agreement with the on-ground measurements. The in-flight validation confirms the expected performance of the visible-light channel polarimeter. Furthermore, a comparison between the first polarized brightness value obtained by Metis and the polarized brightness values obtained by the space-based coronagraph LASCO and the ground-based coronagraph K-Cor shows the consistency of the Metis calibrated results. [ABSTRACT FROM AUTHOR]

The slow solar wind belt in the quiet corona, observed with the Metis coronagraph on board Solar Orbiter on May 15, 2020, during the activity minimum of the cycle 24, in a field of view extending from 3.8 R ⊙ to 7.0 R ⊙ , is formed by a slow and dense wind stream running along the coronal current sheet, accelerating in the radial direction and reaching at 6.8 R ⊙ a speed within 150 and 190 km s−1, depending on the assumptions on the velocity distribution of the neutral hydrogen atoms in the coronal plasma. The slow stream is separated by thin regions of high velocity shear from faster streams, almost symmetric relative to the current sheet, with peak velocity within 175 and 230 km s−1 at the same coronal level. The density–velocity structure of the slow wind zone is discussed in terms of the expansion factor of the open magnetic field lines that is known to be related to the speed of the quasi-steady solar wind, and in relation to the presence of a web of quasi-separatrix layers, S-web, the potential sites of reconnection that release coronal plasma into the wind. The parameters characterizing the coronal magnetic field lines are derived from 3D MHD model calculations. The S-web is found to coincide with the latitudinal region where the slow wind is observed in the outer corona and is surrounded by thin layers of open field lines expanding in a non-monotonic way. [ABSTRACT FROM AUTHOR]

Context. The Solar Orbiter spacecraft will be equipped with a wide range of remote-sensing (RS) and in situ (IS) instruments to record novel and unprecedented measurements of the solar atmosphere and the inner heliosphere. To take full advantage of these new datasets, tools and techniques must be developed to ease multi-instrument and multi-spacecraft studies. In particular the currently inaccessible low solar corona below two solar radii can only be observed remotely. Furthermore techniques must be used to retrieve coronal plasma properties in time and in three dimensional (3D) space. Solar Orbiter will run complex observation campaigns that provide interesting opportunities to maximise the likelihood of linking IS data to their source region near the Sun. Several RS instruments can be directed to specific targets situated on the solar disk just days before data acquisition. To compare IS and RS, data we must improve our understanding of how heliospheric probes magnetically connect to the solar disk. Aims. The aim of the present paper is to briefly review how the current modelling of the Sun and its atmosphere can support Solar Orbiter science. We describe the results of a community-led effort by European Space Agency's Modelling and Data Analysis Working Group (MADAWG) to develop different models, tools, and techniques deemed necessary to test different theories for the physical processes that may occur in the solar plasma. The focus here is on the large scales and little is described with regards to kinetic processes. To exploit future IS and RS data fully, many techniques have been adapted to model the evolving 3D solar magneto-plasma from the solar interior to the solar wind. A particular focus in the paper is placed on techniques that can estimate how Solar Orbiter will connect magnetically through the complex coronal magnetic fields to various photospheric and coronal features in support of spacecraft operations and future scientific studies. Methods. Recent missions such as STEREO, provided great opportunities for RS, IS, and multi-spacecraft studies. We summarise the achievements and highlight the challenges faced during these investigations, many of which motivated the Solar Orbiter mission. We present the new tools and techniques developed by the MADAWG to support the science operations and the analysis of the data from the many instruments on Solar Orbiter. Results. This article reviews current modelling and tool developments that ease the comparison of model results with RS and IS data made available by current and upcoming missions. It also describes the modelling strategy to support the science operations and subsequent exploitation of Solar Orbiter data in order to maximise the scientific output of the mission. Conclusions. The on-going community effort presented in this paper has provided new models and tools necessary to support mission operations as well as the science exploitation of the Solar Orbiter data. The tools and techniques will no doubt evolve significantly as we refine our procedure and methodology during the first year of operations of this highly promising mission. [ABSTRACT FROM AUTHOR]

This paper describes the innovative optical design of the Metis coronagraph for the Solar Orbiter ESA-NASA mission. Metis is a multi-wavelength, externally occulted telescope for the imaging of the solar corona in both the visible and ultraviolet wavelength ranges. Metis adopts a novel occultation scheme for the solar disk, that we named "inverse external occulter", for reducing the extremely high thermal load on the instrument at the spacecraft perihelion. The core of the Metis optical design is an aplanatic Gregorian telescope common to both the visible and ultraviolet channels. A suitable dichroic beam-splitter, optimized for transmitting a narrow-band in the ultraviolet (121.6 nm, HI Lyman-α) and reflecting a broadband in the visible (580–640 nm) spectral range, is used to separate the two optical paths. Along the visible light optical path, a liquid crystal electro-optical modulator, used for the first time in space, allows making polarimetric measurements. [ABSTRACT FROM AUTHOR]

We derived maps of the solar wind outflow velocity of coronal neutral hydrogen atoms at solar minimum in the altitude range 1.5–4.0 R⊙. We applied the Doppler dimming technique to coronagraphic observations in the UV H I Lyα line at 121.6 nm. The technique exploits the intensity reduction in the coronal line with increasing velocities of the outflowing plasma to determine the solar wind velocity by iterative modelling. The Lyα line intensity is sensitive to the wind outflow velocity and also depends on the physical properties of coronal particles and underlying chromospheric emission. Measurements of irradiance by the chromospheric Lyα radiation in the corona are required for a rigorous application of the Doppler dimming technique, but they are not provided by past and current instrumentations. A correlation function between the H I 121.6 nm and He II 30.4 nm line intensities was used to construct Carrington rotation maps of the non-uniform solar chromospheric Lyα radiation and thus to compute the Lyα line irradiance throughout the outer corona. Approximations concerning the temperature of the scattering H I atoms and exciting solar disc radiation were also adopted to significantly reduce the computational time and obtain a faster procedure for a quick-look data analysis of future coronagraphic observations. The effect of the chromospheric Lyα brightness distribution on the resulting H I outflow velocities was quantified. In particular, we found that the usual uniform-disc approximation systematically leads to an overestimated velocity in the polar and mid-latitude coronal regions up to a maximum of about 50−60 km s−1 closer to the Sun. This difference decreases at higher altitudes, where an increasingly larger chromospheric portion, including both brighter and darker disc features, contributes to illuminate the solar corona, and the non-uniform radiation condition progressively approaches the uniform-disc approximation. [ABSTRACT FROM AUTHOR]

The magnetic field shapes the structure of the solar corona, but we still know little about the interrelationships between the coronal magnetic field configurations and the resulting quasi-stationary structures observed in coronagraphic images (such as streamers, plumes, and coronal holes). One way to obtain information on the large-scale structure of the coronal magnetic field is to extrapolate it from photospheric data and compare the results with coronagraphic images. Our aim is to verify whether this comparison can be a fast method to systematically determine the reliability of the many methods that are available for modeling the coronal magnetic field. Coronal fields are usually extrapolated from photospheric measurements that are typically obtained in a region close to the central meridian on the solar disk and are then compared with coronagraphic images at the limbs, acquired at least seven days before or after to account for solar rotation. This implicitly assumes that no significant changes occurred in the corona during that period. In this work, we combine images from three coronagraphs (SOHO/LASCO-C2 and the two STEREO/SECCHI-COR1) that observe the Sun from different viewing angles to build Carrington maps that cover the entire corona to reduce the effect of temporal evolution to about five days. We then compare the position of the observed streamers in these Carrington maps with that of the neutral lines obtained from four different magnetic field extrapolations to evaluate the performances of the latter in the solar corona. Our results show that the location of coronal streamers can provide important indications to distinguish between different magnetic field extrapolations. [ABSTRACT FROM AUTHOR]

Fusarium oxysporum f. sp. lactucae (FOL) is a soil‐ and seedborne pathogen and the causal agent of fusarium wilt on lettuce. Four races have been identified within FOL, with different worldwide distribution. Several molecular techniques have been used to detect and identify this pathogen; however, not all of them have the optimal characteristics in terms of sensitivity to perform FOL detection in plant and seed material. A loop‐mediated isothermal amplification (LAMP) assay was developed based on the sequence‐characterized amplified region (SCAR) obtained in a previous rapid amplification of polymorphic DNA (RAPD) study. The LAMP assay has been validated according to the EPPO standard PM7/98. The LAMP assay was tested with lettuce seeds, soil and plant material, and can be used successfully to amplify DNA from each of these matrices. In seed lots artificially inoculated with FOL, the detection limit of the LAMP test was 0.004% infected seed. [ABSTRACT FROM AUTHOR]

Aims. We investigate the increase of the differential emission measure (DEM) towards the chromosphere due to small and cool magnetic loops (height ≲8 Mm, T ≲ 105 K). In a previous paper, we analysed the conditions of existence and stability of these loops through hydrodynamic simulations, focussing on their dependence on the details of the optically thin radiative loss function. Methods. In this paper, we extend those hydrodynamic simulations to verify if this class of loops exists and is stable when using an optically thick radiative loss function. We study two cases: constant background heating and a heating depending on the density. The contribution to the transition region extreme-UV output of these loops is also calculated and presented. Results. We find that stable, quasi-static cool loops can be obtained using an optically thick radiative loss function and a background heating depending on the density. The DEMs of these loops, however, fail to reproduce the observed DEM for temperatures between 4.6 < log T < 4.8. We also show the transient phase of a dynamic loop obtained by considering constant heating rate and find that its average DEM, interpreted as a set of evolving dynamic loops, reproduces the observed DEM very well. [ABSTRACT FROM AUTHOR]

Optical tweezers are a key technique for trapping and contactless manipulation of particles at the micro- and nanoscale that can exert and sense forces from hundreds of piconewton down to few femtonewton. In their simplest implementation, they are based on a single laser beam tightly focused to a high-intensity diffraction-limited spot. Here, after reviewing the general theoretical background on optical forces, we focus on their calibration and show a comparison between frequency and time domain methods. Then, we show novel measurements and calculations of optical forces on gold nanoparticles discussing their size scaling behavior. Finally, we describe recent applications of chiral optical trapping to soft materials, and integration of optical tweezers with Raman spectroscopy for ultra-sensitive spectroscopy of biomolecules in liquids. [ABSTRACT FROM AUTHOR]

Aims To identify cultivable filamentous fungi before ensiling, after silage conservation, in farm-silos covered with two different plastic films (polyethylene (PE) vs biodegradable (MB)), as well as after aerobic exposure of whole-crop corn silage. Methods and Results Molecular techniques coupled with traditional microbial counting were utilized to identify the predominant fungal species. The cultivable fungal population changed remarkably from harvesting to silo opening. Anaerobiosis and low pH reduced mould count and the presence of Fusarium species both under PE and MB film. However, in the peripheral areas of the silo, where air penetration could not be completely prevented, the fungal population did not decrease. The predominant fungal species after aerobic exposure of silage was Aspergillus fumigatus, without differences between the two plastic films. Conclusions Maintenance of anaerobiosis and a low pH also in the upper layer of the silo reduce the risk of mould growth during corn silage feed-out. Significance and Impact of the Study Even if the new MB plastic film did not completely maintain the anaerobiosis in the upper layer of silage, the overall silage quality was not compromised and was similar to that observed under PE, indicating that the development and use of MB film to cover silage is promising, but needs some improvement. [ABSTRACT FROM AUTHOR]

The present work studies the characteristics of an equatorial streamer visible above the east limb of the Sun on March 2008, during the most recent minimum of solar activity. We analysed the visible light coronagraphic images of SOHO/LASCO and the ultraviolet observations in the HI Lyα spectral line obtained by SOHO/UVCS, and exploited the Doppler dimming effect of the coronal Lyα line to derive the outflow velocity profile of the scattering neutral hydrogen atoms in the streamer region. Taking advantage of the synergy between visible light and ultraviolet observations, we were able to determine all the properties of the coronal structure. In particular, the actual extent of the streamer along the line of sight has been evaluated for the first time. In so doing, the solar wind outflow velocity turned out to be the only free parameter in the theoretical modelling of the Lyα intensity. We found nearly static conditions below 3.5 R☉ along the streamer axis, whereas the solar wind flows at velocities from 40 kms-1 to 140 km s-1 in the altitude range 2.5-5.0 R☉ along the southern boundary of the streamer. We also derived the intensity distribution of the F coronal component in the LASCO C2 field of view, by combining total and polarized brightness data. Finally, we investigated the dependence of the Lyα resonant scattering process on the kinetic temperature of the coronal neutral hydrogen atoms and found that the value of this temperature mostly affects the scattering process at low heliocentric distances, where the solar wind flows with low velocity. [ABSTRACT FROM AUTHOR]

Samples of Ag nanoparticles (AgNPs) in a poly-methacrylic acid (PMA) matrix have been prepared by a photo-induced reduction process. They have been widely characterized by SEM, EDX-mapping, TEM, XRD and XPS measurements. The results have shown that the morphological and microstructural characteristics of AgNPs formed in a PMA matrix depend on the Ag/PMA molar ratio. Thick films of these samples deposited on ceramic substrates have also been prepared. The formation of Ag dendritic structures has been evidenced in samples with a low Ag/PMA ratio, whereas at a higher Ag/PMA ratio the film surface was found to be highly heterogeneous, along with an increase in Ag species in the ionic form. Loading AgNPs/PMA samples with multi-walled carbon nanotubes (MWCNTs) allowed production of conductive films suitable for sensing applications. The samples synthesized were investigated as sensing materials for fabricating ammonia (NH3) gas resistive sensors. The novel sensors developed are active at low temperature, exhibiting fast response/recovery times in a wide range of detection levels from ppm to v/v (%). [ABSTRACT FROM AUTHOR]

We investigated the substantial restructuring of the outer solar corona in the aftermath of the halo CME that occurred on 9 March 2012. To perform our analysis, we used SOHO/LASCO, STEREO/COR1 and SDO/AIA data, which provide observations from different viewpoints. In particular, we applied the polarization ratio technique to the COR1 calibrated images to derive the three-dimensional structure of the CME and determine its direction and speed of propagation. We also estimated the CME mass from a sequence of four observations of the event and obtained values of up to 2.2×1016 g. The COR1 images show a brightness decrease in the coronal sector where the CME propagates. We verified that this intensity reduction is due to a plasma depletion. Moreover, the combined analysis performed by the two STEREO satellites allowed us to deduce that a preexisting streamer is located along the propagation direction of the CME and disappears after the passage of the event. The coronal mass loss associated with the plasma depletion is much lower than the mass expelled from the Sun in the COR1-B data. Conversely, the COR1-A obsevations allowed us to infer that the mass of the streamer carried away from the outer corona corresponds to about half of the CME mass. The results highlight the importance of stereoscopic observations in the study of corona restructuring in the aftermath of a CME event. [ABSTRACT FROM AUTHOR]

This research note extends a previous work focused on the 2D reconstruction of the spatial distribution and temporal evolution of the plasma density fluctuations in the outer solar corona and based on STEREO COR1-A white-light observations. By using the corresponding total brightness images obtained in the same observational period with the coronagraph COR1-B onboard the "Behind" twin STEREO-B spacecraft, and adopting the same methodological approach as for COR1-A data, it was possible to confirm the results of the previous work and argue for the 3D configuration of the fluctuations of the coronal plasma. This provides further evidence in support of a scenario in which the fluctuating features, which are recurrent and spatially coherent, are localized along the magnetic field lines and points out the crucial role played by the 3D magnetic field topology in the confinement and evolution of the plasma density fluctuations. [ABSTRACT FROM AUTHOR]

In this work we study the kinematics of three small-scale (0.01 R☉) blobs of chromospheric plasma falling back to the Sun after the huge eruptive event of June 7, 2011. From a study of 3D trajectories of blobs made with the Solar TErrestrial RElations Observatory (STEREO) data, we demonstrate the existence of a significant drag force acting on the blobs and calculate two drag coefficients, in the radial and tangential directions. The resulting drag coefficients CD are between 0 and 5, comparable in the two directions, making the drag force only a factor of 0.45-0.75 smaller than the gravitational force. To obtain a correct determination of electron densities in the blobs, we also demonstrate how, by combining measurements of total and polarized brightness, the Hα contribution to the white-light emission observed by the COR1 telescopes can be estimated. This component is significant for chromospheric plasma, being between 95 and 98% of the total white-light emission. Moreover, we demonstrate that the COR1 data can be employed even to estimate the Hα polarized component, which turns out to be in the order of a few percent of Hα total emission from the blobs. If the drag forces acting on small-scale blobs reported here are similar to those that play a role during the CME propagation, our results suggest that the magnetic drag should be considered even in the CME initiation modelling. [ABSTRACT FROM AUTHOR]

This work focuses on the first results from the identification and characterization of periodic plasma density fluctuations in the outer corona, observed in STEREO-A COR1 white-light image time series. A two-dimensional reconstruction of the spatial distribution and temporal evolution of the coronal fluctuation power has been performed over the whole plane of the sky, from 1.4 to 4.0 R☉. The adopted diagnostic tool is based on wavelet transforms. This technique, with respect to the standard Fourier analysis, has the advantage of localizing non-persistent fluctuating features and exploring variations of the relating wavelet power in both space and time. The map of the variance of the coronal brightness clearly outlines intermittent spatially coherent fluctuating features, localized along, or adjacent to, the strongest magnetic field lines. In most cases, they do not correspond to the visible coronal structures in the brightness maps. The results obtained provide a scenario in which the solar corona shows quasi-periodic, non-stationary density variations characterized by a wide range of temporal and spatial scales and strongly confined by the magnetic field topology. In addition, structures fluctuating with larger power are larger in size and evolve more slowly. The characteristic periodicities of the fluctuations are comparable to their lifetimes. This suggests that plasma fluctuations lasting only one or two wave periods and initially characterized by a single dominant periodicity either rapidly decay into a turbulent mixed flow via nonlinear interactions with other plasma modes, or they are damped by thermal conduction. The periodic non-stationary coronal fluctuations outlined by the closed field lines at low and mid latitudes might be associated with the existence of slow standing magneto-acoustic waves excited by the convective supergranular motion. The fluctuating ray-like structures observed along open field lines appear to be linked either to the intermittent nature of the processes underlying the generation of magnetic reconnection in the polar regions or to the oscillatory transverse displacements of the coronal ray itself. [ABSTRACT FROM AUTHOR]

Aims. We investigate the capability of multistranded loop models subject to nanoflare heating to reproduce the properties recently observed in coronal loops at extreme ultraviolet (EUV) wavelengths. Methods. One-dimensional hydrodynamic simulations of magnetic loop strands were performed with an impulsive, footpoint-localised heating, with a moderate asymmetry between the two loop halves that was produced either by a sequence of identical nanoflares with a given cadence time tC or by a single energy pulse. The temporal evolution of the emission of a multistranded loop was modelled by simply combining the results of independent single-strand simulations, neglecting any spatial interaction among the strands, and was compared with TRACE and SDO/AIA light curves. The density excess with respect to hydrostatic equilibrium (the ψ factor) was evaluated with the filter-ratio technique. Results. Both loop models exhibit a density excess compared with hydrostatic equilibrium models, which agrees well with the observed values (1 ≲ ψ ≲ 12). However, in the single-pulse model the light curve and density excess maxima do not match. On the other hand, the models with a sequence of nanoflares predict strong emission at lower temperatures that cannot be reconciled with the available observations. [ABSTRACT FROM AUTHOR]

Aims. We aim to investigate the increase of the differential emission measure (DEM) towards the chromosphere. In the past 30 years, small and cool magnetic loops (height ≲8 Mm, T ≲ 105 K) have been proposed as an explanation for this effect. Methods. We present hydrodynamic simulations of low-lying cool loops in which we studied the loops' conditions of existence and stability, and their contribution to the transition region EUV output. Results. We find that stable, quasi-static cool loops (with velocities <1 kms-1) can be obtained under different and more realistic assumptions on the radiative loss function with respect to previous works. Amixture of the DEMs of these cool loops plus intermediate loops with temperatures between 105 and 106 K can reproduce the observed emission of the lower transition region at the critical turnup temperature point (T ∼ 2 × 105 K) and below T = 105 K. [ABSTRACT FROM AUTHOR]

Aspergillus carbonarius is known to colonize and produce ochratoxin A (OTA) on grapes and its derived products which is harmful to humans. We screened and tested A. carbonarius strains which isolated from grapes for production of OTA and selected three high OTA producing strains (ACSP1, ACSP2, ACSP3) for this study. These strains were further tested for their ability to produce OTA at different ecological factors [temperature 15, 25, 30, 35°C; water activity (aw) 0.98, 0.95, 0.90, 0.88; and pH 4.0, 7.0, 9.0, 10.0]. Out of the three strains tested, A. carbonarius ACSP3 produced high levels of OTA than ACSP2 and ACSP1 in all the ecological factors. At 30°C A. carbonarius strains produced the highest OTA compared with other temperature regimes. With reference to water activity, aw 0.98 favoured mycelial growth and accumulation of more OTA with all the three A. carbonarius strains. Further, pH 4.0 was encouraged the greatest production of OTA in all the strains. No growth was observed at aw 0.88 and pH 10.0 in all the three strains except the strain ACSP3 at high pH. Our work demonstrated that temperature 30°C, aw 0.98 and pH 4.0 is optimum for growth and production of OTA by A. carbonarius strains. Maximum amounts of OTA were found at earlier growth stages (7-9 days of incubation) in all the strains of A. carbonarius. The present study revealed that different ecological factors had great impact on OTA production by A. carbonarius which is useful for understanding OTA contamination and to develop proper management practices in future research programmes. [ABSTRACT FROM AUTHOR]

Between 2006 and 2008, 146 isolates of Fusarium spp. were obtained from bakanae-diseased rice plants and seeds from the major rice-growing regions of Italy. These isolates were identified based on translation elongation factor (EF-1α) sequence and pathogenicity tests were used to assess their aggressiveness against the susceptible rice cultivar Galileo. Use of the EF-1α sequence gave reliable identification and showed that Fusarium fujikuroi, the causal agent of bakanae disease, was the most abundant Fusarium spp. isolated. These data were confirmed by inoculation of the isolates to rice seeds which were then germinated in the greenhouse, showing that only F. fujikuroi isolates were able to cause bakanae disease. Pathogenic isolates were identified with different levels of aggressiveness. Phylogenetic analysis based on EF-1α sequences generated a tree which separated the various Fusarium species into different clusters with high bootstrap values. [ABSTRACT FROM AUTHOR]

Titanium oxide nanoparticles in H2O-distilled solvent were prepared by irradiating a Ti target with a Nd:YAG laser (second harmonic, 532 nm), varying the operative fluence in the range 1-8 J/cm2 and the ablation time from 10 to 60 min. The as-prepared nanocolloid samples have been examined and the effects of the ablation parameters on the morphological and structural properties of the grown nanostructures have been investigated by means of UV-VIS and transmission electron microscopy (TEM) measurements, in relation to ablation parameters. At low fluences and long ablation times, TEM measurements pointed out the presence of a high density of nanostructures with diameters of 2-3 nm. While varying the ablation parameters in the operative range, the presence of 50-100 nm diameter nanoparticles becomes predominant. Moreover, as shown by X-ray photoelectron spectroscopy analysis, both the structural typologies are formed by different Ti suboxide phases with a predominance of the TiO2 phase. [ABSTRACT FROM AUTHOR]

Indium oxide nanoparticles (NPs) have been produced by means of a laser ablation in liquid technique by irradiating with a second harmonic (532 nm) Nd:YAG laser beam a metallic indium (In) target immersed in distilled water and varying the laser fluence up to 10 J/cm2 for an ablation time up to 30 min. The colloidal solutions have been examined and the effects of the fluence on the morphological properties have been investigated by means of TEM and SEM-EDX microscopy. Nanostructures of small diameter (2-5 nm) accompanied by larger NPs (about 10-20 nm in diameter) have been observed at all of the operative fluence values that, as shown from UV-VIS measurements, seem to be mainly effective only on the amount of the NPs produced. [ABSTRACT FROM AUTHOR]

Carbon nitride thin films have been deposited by pulsed laser ablation of graphite targets in a controlled nitrogen/argon atmosphere. The experiments were performed by irradiating the targets with the output of a KrF laser at two different laser fluences and both in a plasma regime of free expansion and of shock wave formation. The sample compositions were determined by means of X-ray photoelectron spectroscopy. A study of the C1s and N1s core level photoemission bands evidenced nitrogen atomic contents up to 26%, with respect to carbon. Raman and XPS spectroscopy results clearly indicate that there is a strong correlation between the plasma expansion dynamics and the laser fluence with the structural properties of the deposited thin films. [ABSTRACT FROM AUTHOR]

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Pear, peach, apricot, and mixed juices (125 samples) were purchased in Italian supermarkets and organic food shops and analysed for patulin content. An overall incidence of 34.4? was observed in the fruit juices, with a mean contamination level of 3.6 µg kg-1. No one sample exceeded 50 µg kg-1, the maximum permitted limit according to European legislation. However, 19 positive samples contained more than 10 µg kg-1 of patulin, which is the maximum level permitted for baby food. The incidence of patulin contamination was significantly higher in pear juices (64.1?) than in apricot, peach, or mixed juices. Statistical analysis (p = 0.002; Kruskal-Wallis test) showed a significantly higher level of patulin in pear (5.1 µg kg-1) and mixed juices (4.9 µg kg-1) than in the other juices. A slightly higher incidence of positive samples was found in conventional juices (35.7?) compared with the organic ones (29.6?). The magnitude between the mean contamination levels was similar in conventional (3.6 µg kg-1) and organic (3.3 µg kg-1) juices (p = 0.474; Mann-Whitney U-test). Samples were further divided based on the fruit content in fruit juices, fruit nectars, and fruit drinks. In fruit nectars the incidence of positive samples (37.8?) was slightly higher than in fruit drinks (27.2?), but the mean patulin contamination was higher in fruit drinks (5.2 µg kg-1) than in fruit nectars (3.4 µg kg-1). However, the magnitude between the two means was not statistically different (p = 0.734; Mann-Whitney U-test). Italian juices had a higher incidence of patulin (35.3?), with a lower mean content (3.5 µg kg-1), compared with the incidence (22.2?) and level (4.1 µg kg-1) foreign juices commercially available in Italy. The magnitude of the means between Italian and foreign juices was not statistically different, according to the Mann-Whitney U-test (p = 0.616). The estimated intake of patulin ranged from 0.1 to 1.5 ng kg-1 body weight for the whole population and from 0.3 to 5.1 ng kg-1 body weight for the consumers only. The highest patulin intake was estimated for consumers of pear juices, followed by consumers of mixed juices. The daily intake of patulin derived from the consumption of pear juice suggests that also pear juices, though a minor patulin source, could be monitored for their patulin content in order to control the mycotoxin contamination, especially in countries, such as Italy, where pear nectars are preferred as fruit drinks. [ABSTRACT FROM AUTHOR]

The amphipod Melita plumulosa is commonly used to assess the toxicity of contaminated sediments. Seven-day-old M. plumulosa are <1 mm in size, and during 10-day tests in sandy sediments with low nutritional value, starvation can cause >50% mortality. In sediment toxicity tests, therefore, it can be difficult to determine if toxicity is due to contaminants or starvation, particularly in contaminated sandy sediments. This study investigated the influence of amphipod age and food addition on amphipod survival in toxicity tests. The 4-day LC50 increased linearly from 120 to 470 μg/L when M. plumulosa age at the beginning of the test increased from 5 to 30 days. The addition of food as algae or fish food did not significantly affect the sensitivity of 11-day-old M. plumulosa (11-d Mp) to dissolved copper over 4 days in water-only tests. The survival of 11-d Mp in water-only tests over 10 days was poor without feeding, but when fed fish food, the 10-day LC50 was 76 ± 15 μg/L. In sediment tests, feeding 0.063 mg fish food/amphipod on days 3 and 7 of 10-day tests consistently resulted in greater than 80% survival of 11-d Mp for a range of clean, sandy sediments, which had low amphipod survival without added food. Algae were not always suitable as a food source, as their growth can be stimulated by nutrients released from sediment and was inhibited by contaminants. The toxicity of most contaminated sediments was not ameliorated by the addition of food, suggesting that food addition was suitable for inclusion in routine testing protocols for this amphipod. [ABSTRACT FROM AUTHOR]

Background In postmenopausal women, an increase in insulin resistance is associated with an increased risk of diabetes, cardiovascular disease and breast cancer. Hormone replacement therapy (HRT) can reduce insulin resistance and coffee use is reported to decrease the incidence of diabetes. The aim of our study was to assess possible concurrent effects of HRT and espresso coffee intake on insulin resistance and on interdependent nutritional and clinical features. Methods A total of 478 healthy postmenopausal, non-diabetic women (aged 54.5 ± 4.2 years) were studied: 360 had been on HRT for at least 2 years and 118 were not treated. Insulin resistance was assessed by a conventional homeostasis model (HOMA-IR). Results Insulin resistance is directly related to body mass index (p < 0.0001), and not with age and blood pressure; hypertensive menopausal women have a slightly higher body mass index but the same degree of insulin resistance as normotensive women. Women on HRT show lower insulin resistance, but not lower prevalence of arterial hypertension. Coffee use is associated with a decrease in insulin resistance in non-obese women receiving HRT, but not in other subsets. Conclusions The combination of coffee consumption and HRT could lower insulin resistance in postmenopausal women. In overweight women, greater insulin sensitivity is associated with intake of espresso coffee and not with HRT; in normal weight women, only HRT is associated with lower insulin resistance. [ABSTRACT FROM AUTHOR]

The objectives of this study were to determine whether patients would be willing to pay for pharmacist self-care services on proper use of over-the-counter medications. In addition, we examined whether patients’ willingness to pay was associated with community pharmacy setting and patients’ socio-economic factors.A self-administered questionnaire was handed out to patrons of community pharmacies in Arkansas, USA. The questionnaire contained question items related to patients’ willingness to pay, community pharmacy setting, prescription drug insurance and socio-economic information. Patients’ willingness to pay was measured using the checklist method.A total of 262 questionnaires were completed. More than twice as many patients (51%) are now willing to pay for pharmacist services for patient self care than a decade ago. They were willing to pay about$5 for a 5-min consultation. Willingness to pay was significantly associated with community pharmacy setting (chi-square,P = 0·030). Grocery/chain pharmacy patrons were more willing to pay than independent pharmacy patrons.This increased patient willingness to pay, along with growing self-care markets, provides pharmacists with opportunities to develop self-care clinics or services. [ABSTRACT FROM AUTHOR]

We investigated the UV emission expected from solar coronal transients, selecting some spectral lines which will be observed with the UVCS spectrocoronagraph onboard the SOHO spacecraft. The line intensities were calculated starting from a representative, simplified model of coronal transient. We discuss how the considered intensities depend on the physical parameters of the examined structures. This work is aimed to give a contribution in defining and preparing the future observations of coronal transients and coronal mass ejections by the UVCS/SOHO. [ABSTRACT FROM AUTHOR]

The SOHO Ultraviolet Coronagraph Spectrometer (UVCS/SOHO) is being used to observe the extended solar corona from 1.25 to 10 R⊙ from Sun center. Initial observations of polar coronal holes and equatorial streamers are described. The observations include measurements of spectral line profiles for HI Lα and Lβ, Ovi 1032 Å and 1037 Å, Mgx 625 Å, Fexii 1242 Å and several others. Intensities for Mgx 610 Å, Sixii 499 Å, and 520 Å, Sx 1196 Å, and 22 others have been observed. Preliminary results for derived H0, O5+, Mg9+, and Fe11+ velocity distributions and initial indications of outflow velocities for O5+ are described. In streamers, the H0 velocity distribution along the line of sight (specified by the value at e-1, along the line of sight) decreases from a maximum value of about 180 km s-1 at 2 R⊙ to about 140 km s-1 at 8 R⊙. The value for O5+ increases with height reaching a value of 150 km s-1 at 4.7 R⊙. In polar coronal holes, the O5+ velocity at e-1 is about equal to that of H0 at 1.7 R⊙ and significantly larger at 2.1 R⊙. The O5+ in both streamers and coronal holes were found to have anisotropic velocity distributions with the smaller values in the radial direction. [ABSTRACT FROM AUTHOR]

The Ultraviolet Coronagraph Spectrometer on the SOHO satellite covers the 940–1350 Å range as well as the 470–630 Å range in second order. It has detected coronal emission lines of H, N, O, Mg, Al, Si, S, Ar, Ca, Fe, and Ni, particularly in coronal streamers. Resonance scattering of emission lines from the solar disk dominates the intensities of a few lines, but electron collisional excitation produces most of the lines observed. Resonance, intercombination and forbidden lines are seen, and their relative line intensities are diagnostics for the ionization state and elemental abundances of the coronal gas. The elemental composition of the solar corona and solar wind vary, with the abundance of each element related to the ionization potential of its neutral atom (First Ionization Potential–FIP). It is often difficult to obtain absolute abundances, rather than abundances relative to O or Si. In this paper, we study the ionization state of the gas in two coronal streamers, and we determine the absolute abundances of oxygen and other elements in the streamers. The ionization state is close to that of a log T = 6.2 plasma. The abundances vary among, and even within, streamers. The helium abundance is lower than photospheric, and the FIP effect is present. In the core of a quiescent equatorial streamer, oxygen and other high-FIP elements are depleted by an order of magnitude compared with photospheric abundances, while they are depleted by only a factor of 3 along the edges of the streamer. The abundances along the edges of the streamer (‘legs’) resemble elemental abundances measured in the slow solar wind, supporting the identification of streamers as the source of that wind component. [ABSTRACT FROM AUTHOR]

We describe a CME event, occurred in NOAA 11059 on April 3 2010, using STEREO and MDI/SOHO data. We analyze the CME evolution using data provided by SECCHI-EUVI and COR1 onboard STEREO satellites, and we perform a 3D reconstruction of the CME using the LCT-TP method. Using MDI/SOHO line-of-sight magnetograms we analyze the magnetic configuration of NOAA 11059 and we determine the magnetic helicity trend. [ABSTRACT FROM PUBLISHER]

We investigate whether temperature sensitive EUV line ratios can be used as observational signatures for the presence of non-equilibrium ionization in transition region plasma. We compute the total intensity of some EUV lines of carbon and oxygen expected from coronal loop models with a steady-state flow and which are known to have significant departures from ionization equilibrium, selecting lines whose intensity ratios are useful for deducing the electron temperature in the coronal plasma. We calculate the intensity ratios with and without the approximation of ionization equilibrium, in order to determine the effects of any deviations from equilibrium on the numerical values of the line ratios examined. [ABSTRACT FROM AUTHOR]

An abstract of the article "New Microbial Antagonists and Thermotherapy as Seed Treatmens Against Fusarium fujikuroi on Rice" by D. Spadaro and colleagues is presented.

An abstract on the study pertaining to the expression of defense-related genes and production of phytoalexins in rice cultivars resistant to Fusarium fujikuroi is presented.

Due to the reduction in pesticide availability, in recent years the incidence of bakanae disease on rice has grown in Italy. Fusarium fujikuroi is the causal agent of bakanae disease and a species in the Gibberella fujikuroi species complex (GFSC). Other Fusarium spp. also occur on rice including two other species of the GFSC, Fusarium verticillioides and Fusarium proliferatum. In particular, F. proliferatum is morphologically indistinguishable from F. fujikuroi and can only be distinguished by making tests of sexual cross-fertility or through DNA sequencing. Multiple alignment of translation elongation factor (TEF) gene sequences of different Fusarium spp., showed a deletion of six nucleotides in F. fujikuroi sequence and a two nucleotide polymorphism in the same region of F. proliferatum sequence. These elements of variability were used to develop a conventional and real-time PCR assay for diagnosis. The species specific primer pairs (Fuji1F/TEF1R and Proli1F/TEF1R) gave a product of 179 and 188 bp for F. fujikuroi and F. proliferatum, respectively. Primer specificity was confirmed by analysing the DNA of the most representative species of the GFSC and 298 strains of Fusarium spp. isolated from rice plants and seeds in Italy. The specific primers were also successfully used to detect fungal presence directly from infected rice tissues and seeds, providing a rapid tool for the early detection of pathogen contamination. The early and correct identification of this species is very important for the rice seed industry to set up, when necessary, good control strategies, and to sell disease-free certified seeds. [ABSTRACT FROM AUTHOR]