In the present work, an improved numerical solution for determining the ratio, R Mott , of the unscreened Mott differential cross section (MDCS) with respect to Rutherford's formula is proposed for ...the scattering of electrons and positrons on nuclei with 1 <= Z <= 118 . It accounts for incoming lepton energies between 1 keV and 900 MeV. For both electrons and positrons, a fitting formula and a set of fitting coefficients for the ratio R Mott on nuclei are also presented. The found average error of the latter practical interpolated expression is typically lower than 1% also at low energy for electrons and lower than 0.05% for positrons for all nuclei over the entire energy range.
The expression profile of flavour-related genes during ripening was investigated in two peach genotypes, Bolero and OroA, which have been selected for their contrasting aroma/ripening behaviour. A ...new peach microarray containing 4776 oligonucleotide probes corresponding to a set of ESTs specifically enriched in secondary metabolism (μPEACH2.0) was designed to investigate transcriptome changes during three fruit ripening stages, revealing 1807 transcripts differentially expressed within and between the two genotypes. Differences in the expression of genes involved in the biosynthesis of aroma compounds were detected during the ripening process within and between the two genotypes. In particular, a subset of 12 transcripts involved in metabolism of esters, norisoprenoids, phenylpropanoids and lactones, varied in expression during ripening and between Bolero and OroA.
The cosmic rays differential intensity inside the heliosphere, for energy below 30 GeV/nuc, depends on solar activity and interplanetary magnetic field polarity. This variation, termed solar ...modulation, is described using a 2D (radius and colatitude) Monte Carlo approach for solving the Parker transport equation that includes diffusion, convection, magnetic drift, and adiabatic energy loss. Since the whole transport is strongly related to the interplanetary magnetic field (IMF) structure, a better understanding of his description is needed in order to reproduce the cosmic rays intensity at the Earth, as well as outside the ecliptic plane. In this work an interplanetary magnetic field model including the standard description on ecliptic region and a polar correction is presented. This treatment of the IMF, implemented in the HelMod Monte Carlo code (version 2.0), was used to determine the effects on the differential intensity of Proton at 1 AU and allowed one to investigate how latitudinal gradients of proton intensities, observed in the inner heliosphere with the Ulysses spacecraft during 1995, can be affected by the modification of the IMF in the polar regions.
Abstract Background and aims Behçet syndrome is a systemic inflammatory condition characterized by muco-cutaneous and ocular manifestations, with central nervous system, vascular and/or ...gastro-intestinal involvement. The association of microbiota with Behçet syndrome has not been shown yet. Our work was aimed to compare the gut microbiota structure and the profiles of short-chain fatty acids production in Behçet syndrome patients and healthy control relatives. Methods Here, we compared the fecal microbiota of 22 patients with Behçet syndrome and that of 16 healthy co-habiting controls, sharing the same diet and lifestyle by pyrosequencing of the V3–V4 hypervariable regions of the 16 rDNA gene and biochemical analyses. Results Our analyses showed significant differences in gut microbiota between Behçet patients and healthy cohabitants. In particular we found that Behçet's patients were significantly depleted in the genera Roseburia and Subdoligranulum. Roseburia showed a relative abundance value of 10.45 ± 6.01% in healthy relatives and 4.97 ± 5.09% in Behçet's patients, and Subdoligranulum , which reached a relative abundance of 3.28 ± 2.20% in healthy controls, was only at 1.93 ± 1.75% of abundance in Behçet's patients. Here we report, for the first time, that a peculiar dysbiosis of the gut microbiota is present in patients with Behçet syndrome and this corresponds to specific changes in microbiome profile. A significant decrease of butyrate production ( P = 0.0033) in Behçet's patients was demonstrated. Butyrate is able to promote differentiation of T-regulatory cells, and consequently the results obtained prompt us to speculate that a defect of butyrate production might lead to both reduced T-reg responses and activation of immuno-pathological T-effector responses. Conclusions Altogether, our results indicate that both a peculiar dysbiosis of the gut microbiota and a significant decrease of butyrate production are present in patients with Behçet syndrome.
Bacterial genotoxins, produced by several Gram-negative bacteria, induce DNA damage in the target cells. While the responses induced in the host cells have been extensively studied in vitro, the role ...of these effectors during the course of infection remains poorly characterized. To address this issue, we assessed the effects of the Salmonella enterica genotoxin, known as typhoid toxin, in in vivo models of murine infection. Immunocompetent mice were infected with isogenic S. enterica, serovar Typhimurium (S. Typhimurium) strains, encoding either a functional or an inactive typhoid toxin. The presence of the genotoxic subunit was detected 10 days post-infection in the liver of infected mice. Unexpectedly, its expression promoted the survival of the host, and was associated with a significant reduction of severe enteritis in the early phases of infection. Immunohistochemical and transcriptomic analysis confirmed the toxin-mediated suppression of the intestinal inflammatory response. The presence of a functional typhoid toxin further induced an increased frequency of asymptomatic carriers. Our data indicate that the typhoid toxin DNA damaging activity increases host survival and favours long-term colonization, highlighting a complex cross-talk between infection, DNA damage response and host immune response. These findings may contribute to understand why such effectors have been evolutionary conserved and horizontally transferred among Gram-negative bacteria.
Solar energetic particles (SEP) are a key target of heliophysics research, not only as exemplars of particle acceleration and transport processes that are ubiquitous in astrophysical plasmas, but ...also as the most intense transient radiation hazard for human and robotic space explorers. SEPs are very well-observed by spacecraft covering particle energies below several hundred MeV/nucleon. Multiple missions, stretching back over decades, have yielded a fairly complete description of SEP intensity, energy spectra, and composition up to a few hundred MeV/nucleon. SEP characteristics at higher energies are, by comparison, only poorly understood due to the relative dearth of high-energy measurements. This lack of high energy measurements has contributed to a disagreement within the heliophysics community regarding the source regions and mechanisms that accelerate particles up to GeV energies. In solar cycle 24, the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) and the Alpha Magnetic Spectrometer (AMS) have been taking measurements of the highest energy SEPs from ∼100MeV to the GeV. Since the literature has discussed SEP acceleration to GeV energies in terms of Ground Level Enhancements (GLE), we will review the findings for GLEs in solar cycle 23. We will discuss the models and theories that address acceleration up to the GeV and how AMS and PAMELA measurements have the potential to advance the current understanding of SEP acceleration physics. Lastly, only 1–2 GLEs have occurred during solar cycle 24, so we will explore a set of SEP events that were observed in the ⩾100MeV GOES channels, most of which were also observed by PAMELA and AMS.
A simple, non-destructive procedure is described to determine the quality of DNA arrays before they are used. It consists of a preliminary staining step of the DNA microarray by using SYBR green II, ...a fluorophore with specific affinity for ssDNA, followed by a laser scan analysis. The surface quality, integrity and homogeneity of each DNA spot of the array can thus be assessed. After this preliminary control, which may avoid further analytical steps that lead to the waste of precious biological samples, a fully reversible staining procedure is performed that produces an array ready for subsequent use.
We show the design, development and assessment of disposable, biocompatible, fully plastic microreactors, which are demonstrated to be highly efficient for genomic analyses, such as amplification of ...DNA, quantitative analyses in real time, multiplex PCR (both in terms of efficiency and selectivity), as compared to conventional laboratory equipment for PCR. The plastic microreactors can easily be coupled to reusable hardware, enabling heating/cooling processes and, in the case of qPCR applications, the real-time detection of the signal from a suitable fluorescent reporter present in the reaction mixture during the analysis. The low cost production of these polymeric microreactors, along with their applicability to a wide range of biochemical targets, may open new perspectives towards practical applications of biochips for point of care diagnostics.
We implemented a quasi time-dependent 2-D stochastic model of solar modulation describing the transport of cosmic rays (CR) in the heliosphere. Our code can modulate the Local Interstellar Spectrum ...(LIS) of a generic charged particle (light cosmic ions and electrons), calculating the spectrum at 1 AU. Several measurements of CR antiparticles have been performed. Here we focused our attention on the CR antiproton component and the antiproton over proton ratio. We show that our model, using the same heliospheric parameters for both particles, fit the observed p/p ratio. We show a good agreement with BESS-97 and PAMELA data and make a prediction for the AMS-02 experiment.
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