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The ECN3 Beam Delivery Task Force was mandated by the PBC Study Group to assess the technical feasibility of increasing the proton beam intensity to the ECN3 hall of the North Area to satisfy the demands of a compelling set of PBC experimental physics proposals. This report summarises the findings of the Task Force that converge on a technically feasible solution with an implementation timeline that could exploit and build upon the investment already foreseen as part of Phase 1 of the NA-CONS project, and take the SPS complex into a new intensity frontier for Fixed Target physics in Run4.

Gut microbial acquisition during the early stage of life is an extremely important event since it affects the health status of the host. In this contest the healthy properties of the genus Bifidobacterium have a central function in newborns. The aim of this thesis was to explore the dynamics of the gut microbial colonization in newborns and to suggest possible strategies to maintain or restore a correct balance of gut bacterial population in infants. The first step of this work was to review the most recent studies on the use of probiotics and prebiotics in infants. Secondly, in order to prevent or treat intestinal disorders that may affect newborns, the capability of selected Bifidobacterium strains to reduce the amount of Enterobacteriaceae and against the infant pathogen Streptococcus agalactiae was evaluated in vitro. Furthermore, the ability of several commercial fibers to stimulate selectively the growth of bifidobacterial strains was checked. Finally, the gut microbial composition in the early stage of life in response to the intrapartum antibiotic prophylaxis (IAP) against group B Streptococcus was studied using q-PCR, DGGE and next generation sequencing. The results globally showed that Bifidobacterium breve B632 strain is the best candidate for the use in a synbiotic product coupled to a mixture of two selected prebiotic fibers (galactooligosaccharides and fructooligosaccharides) for gastrointestinal disorders in infants. Moreover, the early gut microbial composition was affected by IAP treatment with infants showing lower counts of Bifidobacterium spp. and Bacteroides spp. coupled to a decrement of biodiversity of bacteria, compared to control infants. These studies have shown that IAP could affect the early intestinal balance in infants and they have paved the way to the definition of new strategies alternative to antibiotic treatment to control GBS infection in pregnant women.

Novel bio-based and biodegradable electrospun membranes, containing bactericidal ricinoleic acid (RA) units either by copolymerization with butylene succinate (BS) units or by blending PRA and PBS homopolymers, are characterized in their chemical, thermal, mechanical and surface properties. In the blends E. coli and S. aureus mortality rate increases with PRA amount, while the copolymer shows lower bactericidal activity compared to the blend with similar composition. XPS demonstrates that in the blends an enrichment of RA units at the fiber surface occurs during electrospinning due to phase separation, while in the copolymer RA units are homogeneously dispersed along fiber cross-section.

Introduction. With the ban of dietary antimicrobial agents in animal farms, the use of probiotics, prebiotics or synbiotics to reduce pathogen load has attracted a great attention. In particular, Campylobacter jejuni has emerged as a leading bacterial cause of food-borne gastroenteritis in humans, mainly due to poultry food chain and poultry products. In a recent work a synbiotic mixture were administered for 15 days to young broilers and qPCR revealed an increase of the beneficial bacteria (i.e. bifidobacteria, lactobacilli) and a reduction of C. jejuni. In the current study the microbial gut community profiles and C. jejuni were evaluated in treated and untreated broilers by PCR-DGGE analysis to better understand the impact of the tested synbiotic product and support qPCR results. Methods. The synbiotic product was composed by the microencapsulated B. longum subsp. longum PCB133 (>109 UFC/g) and a galactooligosaccharide (3% w/w). It was administered to broilers for 15 days directly mixed to normal feed; faecal samples were collected three times along the trial (t0, t15, t20). DNA extracted from faecal samples was analyzed with DGGE technique after amplification with universal primers and with Campylobacter-specific primers (fla-DGGE). Obtained profiles analysed using the GelCompareII software package version 6.1 (Applied Maths, Kortrijk, Belgium). After normalization, a cluster analysis was performed using the Pearson similarity coefficient and unweighted pair group mathematical average (UPGMA) clustering algorithm. Results. DGGE profiles provided evidence that synbiotic consumption did not alter microbial profiles in the fecal microbiota of both untreated and treated animals; nevertheless a shift in the faecal microbiota of both groups was observed, due probably to animal growth and development. Moreover, DGGE results showed that the band corresponding to the administered probiotic strain PCB133 was detected in all treated animals and was persistent after the wash-out period. Preliminary fla-DGGE analysis underlined the effectiveness of the treatment on naturally infected animals. Discussion. The experimental study highlights the positive effect of the synbiotic approach in broiler chickens, confirming the efficacy of the probiotic PCB133 against C. jejuni without perturbation of gut microbial community.