In the framework of the Sardinia Radio Telescope (SRT) Early Science Program, we obtained single-dish high-resolution imaging of the Supernova Remnants IC443 and W44 at 7 GHz. By coupling them with SRT 1.5 GHz maps, we provided spatially-resolved spectral measurements that are highlighting a spread in spectral slope distribution. The observed features range from flat or slightly inverted spectra corresponding to bright radio limbs and filaments, to relatively steep spectra in fainter radio regions. Different theoretical possibilities explaining the above challenging findings are discussed. In particular, we exclude that the observed region-dependent wide spread in spectral slope distribution could be related to absorption processes. Our high-frequency results can be directly related to distinct electron populations in the SNRs including secondary hadronic electrons and resulting from different shocks conditions and/or undergoing different cooling processes. Integrated fluxes associated with the whole SNRs obtained by SRT in comparison with previous results in the literature support the evidence for a slight spectral steepening above 1 GHz for both sources, which could be related to primary electrons or more likely secondary hadronic electrons cut-offs.

We present single-dish imaging of the well-known Supernova Remnants (SNRs) IC443 and W44 at 1.5 GHz and 7 GHz with the recently commissioned 64-m diameter Sardinia Radio Telescope (SRT). Our images were obtained through on-the-fly mapping techniques, providing antenna beam oversampling, automatic baseline subtraction and radio-frequency interference removal. It results in high-quality maps of the SNRs at 7 GHz, which are usually lacking and not easily achievable through interferometry at this frequency due to the very large SNR structures. SRT continuum maps of our targets are consistent with VLA maps carried out at lower frequencies (at 324 MHz and 1.4 GHz), providing a view of the complex filamentary morphology. New estimates of the total flux density are given within 3% and 5% error at 1.5 GHz and 7 GHz respectively, in addition to flux measurements in different regions of the SNRs.

In the framework of the Astronomical Validation and Early Science activities of the Sardinia Radio Telescope (SRT, www.srt.inaf.it), we performed 22 GHz imaging observations of SNR W44 and IC443. Thanks to the single-dish imaging performances of SRT and innovative ad hoc imaging techniques, we obtained maps that provide a detailed view of the structure of the remnants. We are planning to exploit the high-frequency radio data of SNRs to better characterize the spatially-resolved spectra and search for possible spectral steepening or breaks in selected SNR regions, assessing the high-energy tail of the region-dependent electron distribution.

This work shows that realistic irradiation-induced phase separation and the resulting microstructures can be obtained via an adapted Phase Field (PF) modelling combined with atomistic Monte Carlo simulations in the pseudo-grand canonical ensemble. The last allow for calculating the equilibrium phase diagram of the silver-copper alloy, chosen as a model of binary systems with large miscibility gap and, for extracting the parameters of the excess free-energy PF functional. Relying on this methodology, the equilibrium phase diagram of the alloy is predicted in excellent agreement with its experimental counterpart whereas, under irradiation, the predicted microstructures are functions of the irradiation parameters. Different irradiation conditions trigger the formation of various microstructures consistently presented as a non-equilibrium “phase diagram” aiming at facilitating the comparison with experimental observations.

We have used a hydrogel templating technique followed by the subsequent evaporation of water present to fabricate porous cement and porous PDMS composites, and we have analyzed their sound absorption properties. All experiments were carried out with hydrogel slurries of broad bead size distributions. Porous PDMS and cement composites were produced with porosities of up to 80% and 70%, respectively. Scanning electron microscope analysis shows fibrous domains within the voids created by the hydrogel in the cement samples and open pore network in the PDMS composites of initial hydrogel content higher than 70 vol%. Sound absorption was improved with respect to control nonporous samples in all composites with porosities higher than 60 vol%, where an open pore structure was formed. The porous PDMS and porous cement produced by this method show better sound absorption at 200–400 Hz and 1200–1800 Hz frequency ranges when compared with the sound absorption in the intermediate frequencies range between 400 and 1000 Hz.

This work clearly demonstrates that the X Ray Reflectometry technique (XRR), extensively used to assess the quality of microelectronic devices can be a useful tool to study the first stages of ion beam mixing. This technique allows measuring the evolution of the Si concentration profile in irradiated Cr/Si layers. From the analysis of the XRR profiles, it clearly appears that the Si profile cannot be described by a simple error function.

In the past fifty years, experimental works based on TEM or grazing incidence X ray diffraction have clearly shown that alloys and ceramics exhibit a nano pattering under irradiation [1,2,3]. Many works were devoted to study the nano patterning induced by ion beam mixing in solids [17,18,19]. Understanding the nano patterning will provide scientific bases to tailor materials with well-defined microstructures at the nanometric scale. The slowing down of impinging particles in solids leads to a complex distribution of subcascades. Each subcascade will give rise to an athermal diffusion of atoms in the medium. In this work, we focused on this point. Based on the well-known Cahn Hilliard Cook (CHC) equation, we analytically calculate the structure factor describing the nano patterning within the mean field approximation. It has shown that this analytical structure factor mimics the structure factor extracted from direct numerical simulations of the time dependent CHC equation. It appears that this structure factor exhibits a universal feature under irradiation.

We have fabricated novel shellac-cells composite microcapsules capable of pH-stimulus induced release of cells in a narrow pH range. The microcapsules were produced with yeast cells as a model for probiotics which were co-precipitated from an aqueous solution of ammonium shellac doped with pH-sensitive polyelectrolytes. The yeast cells in the composite shellac-cell microcapsules retained their viability even when treated with aqueous solutions of very low pH and subjected to shear stress. We studied the pH triggered release of cells from these microcapsules and measured their disintegration times. These microcapsules showed versatile responses ranging from slow release to explosive swelling at higher pH depending on the type and concentration of the polyelectrolyte integrated in the shellac microcapsules. We also observed growth-triggered release of cells from these microcapsules upon exposure to culture media. In both cases the cells retained their viability following their release from the microcapsules into the aqueous solution.

We used sporopollenin prepared from Lycopodium Clavatum to encapsulate living yeast cells as a model for probiotics. The microencapsulation of cells was achieved by using the trilite scars of the sporopollenin microcapsules which can open up by compressing the sporopollenin into a pellet. Such compressed pellets were exposed to an aqueous suspension of yeast cells in the presence of a biocompatible surface active agent which allowed living cells to be loaded inside the sporopollenin particles by the influx of liquid to the sporopollenin interior as the deformed microcapsules re-inflated to their original state. We demonstrated that the cells viability and biological activity is preserved after the microencapsulation in the sporopollenin. Such microencapsulation technology could find application in preserving cells from mechanical stress and aggressive environments which can be used in protection of probiotics in food formulations.

We have developed a novel class of colloidal particles capable of shape and size recognition as well as specific binding to the target cells. These colloid particles were fabricated using a nanoimprinting technology which yields inorganic imprints of the chosen target microorganisms. The products of the templating process are partially fragmented inorganic shells which can selectively bind to their biological counterparts, therefore impairing microbial cell growth, replication and infection. We have named this class of particles, which are capable of selectively recognizing bacterial shape and size, “nanoantibiotics”, which can be further functionalized to kill the target cells. The selective binding is driven by the increased area of contact upon recognition of the cell shape and size between the cells and their matching inorganic shell fragments. Here, we demonstrate the cell recognition and binding action of such particles using two different microbial test organisms.

We present in this text a new experimental tool to study the mixing of atoms under irradiation. Based on physics of x ray diffraction, the specular reflectivy of x ray was used to estimate the Auto Correlation Function associated with the electron density gradient. The accuracy of the ACF is around 1 nanometer and does not evolve with the thickness of the probed layer. Thus, this point allows accurately measuring the broadening of the electron density gradient spreading induced by irradiation. Such an accurate profile extracted over a large range of fluences (about 3 decades) would lead to the determination of the functional dependence of this spreading with the fluence. This could allow pointing out the main mechanisms triggering the atomic mixing over large distances when atomic mixing occurring in thermal spikes is washed out.

The relationship between varying intensities of Trichuris trichiura infection and iron status was examined in Jamaican schoolchildren, aged 7 to 11 years. A total of 409 children was identified with T. trichiura (epg > 1200). A control group comprised 207 uninfected children who were matched by school and class to every pair of infected subjects. Blood samples were obtained from 421 children: 264 infected and 157 controls. Compared to the rest of the children, those with heavy infections (epg > 10 000) had significantly lower (P < 0·05) Hb (11·5 ± 1·3 vs. 12·1 ± 1·1 g/dl), MCV (78·6 ± 6·3 vs. 81·2 ± 5·5 fl), MCH (26·2 ± 2·9 vs. 27·5 ± 2·5 pg) and MCHC (33·2 ± 1·5 vs. 33·9 ± 1·4 g/dl). Similarly, the prevalence of anaemia (Hb < 11·0 g/dl) amongst heavily infected children (33%) was significantly higher (P < 0·05) than the rest of the sample (11%). These differences remained significant after controlling for confounding variables including socio-economic status, age, gender, area of residence and the presence of Ascaris infections. Differences in red cell count, ferritin, and free erythrocyte protoporphyrin were not statistically significant and showed no association with the infectious load. These results suggest that in the Jamaican children studied, iron deficiency anaemia is associated with Trichuris infections over 10 000 epg, but not with less intense infections.

The effects of mild to moderate infections of Trichuris trichiura on cognitive functions were investigated in Jamaican children aged 7 to 10 years. In all, 189 infected children and 100 uninfected classmates were studied. The infected children were randomly assigned to receive treatment (albendazole) or a placebo. All children were given cognitive tests on enrolment and 14 weeks later. These included verbal fluency (generation of ideas), digit span (working memory), number choice (speed of processing of visual stimuli), visual search (sustained attention) and a French Vocabulary test (paired-associate learning). At baseline, the infected children had lower scores than the uninfected ones in fluency (P = 0·01), search (P = 0·02) and French (P = 0·01). Treatment effects were examined among infected children and there was no significant treatment effect for any of the tests. However, there was a significant treatment by weight-for-age interaction in fluency (P < 0·05). The children with low weight-for-age (Z-score < – 1) improved with treatment while there was no improvement with treatment among the other children. We concluded that treatment of children with mild to moderate T. trichiura infections using albendazole produces little benefit in cognition if they are adequately nourished; however, undernourished children are more likely to benefit.

Zirconia, oxidation product of Zircaloy cladding elements of nuclear plants, exhibits an unusual behaviour under irradiation. Impinging ions and neutrons induce a monoclinic to tetragonal phase transition at room temperature in this solid. To understand this modification of the positions of the stability lines in such a solid under irradiation, we have studied the monoclinic to tetragonal first order phase transition versus temperature in pure micrometric and nanometric zirconia samples. From these works, it was possible to understand the behaviour of this material under irradiation pointing out the key role of defects induced irradiation on its phase diagram.

The growth technique, the micromorphological and microstructural characterization by means of atomic force microscopy (AFM) and secondary ions mass spectrometry (SIMS) as well as the magnetic properties of a novel class of magnetic multilayers, based on radio frequency (RF) sputtered thin amorphous garnet films, are presented. One, three and five thin film multilayers composed by amorphous pure yttrium iron garnet (a:YIG) and amorphous gadolinium gallium garnet (a:GGG) have been grown on GGG single crystal substrates. The multilayer interfaces have been found to be comparable in both, the three and five-layers structure. Low field susceptibility measurements, showed a paramagnetic behaviour for the single layer YIG film. For the three and five layers samples, irreversibility effects were observed, giving evidence of magnetic clusters at the interface YIG/GGG.