A multi-physics approach to simulate the RF heating 3D power map induced by the proton beam in a beam intercepting device

The project High Luminosity Large Hadron Collider (HL-LHC) calls for a streaking beam intensity and brightness in the LHC machine. In such a scenario, beam-environment electromagnetic interactions are a crucial topic: they could lead to uneven power deposition in machine equipment. The resulting irregular temperature distribution would generate local thermal gradients, this would create mechanical stresses which could lead to cracks and premature failure of accelerator devices. This work presents a method to study this phenomenon by means of coupled electro-thermomechanical simulations. Further, an example of application on a real HL-LHC device is also discussed

Analysis on the mechanical effects induced by beam impedance heating on the HL-LHC target dump injection segmented (TDIS) absorber

The High Luminosity Large Hadron Collider (HL-LHC) Project at CERN calls for increasing beam brightness and intensity. In such a scenario, critical accelerator devices need to be redesigned and rebuilt. Impedance is among the design drivers, since its thermo-mechanical effects could lead to premature device failures. In this context, the current work reports the results of a multiphysics study to assess the electromagnetic and thermo-mechanical behaviour of the Target Dump Injection Segmented (TDIS). It first discusses the outcomes of the impedance analysis performed to characterise the resistive wall and the high order resonant modes (HOMs) trapped in the TDIS structures. Then, their RF-heating effects and the related temperature distribution are considered. Finally, mechanical stresses induced by thermal gradients are studied in order to give a final validation on the design qualit

A general model of dioxin contamination in breast milk: results from a study on 94 women from the Caserta and Naples areas in Italy.

BackgroundThe Caserta and Naples areas in Campania Region experience heavy environmental contamination due to illegal waste disposal and burns, thus representing a valuable setting to develop a general model of human contamination with dioxins (PCDDs-PCDFs) and dioxin-like-PCBs (dl-PCBs).Methods94 breastfeeding women (aged 19-32 years; mean age 27.9 ± 3.0) were recruited to determine concentrations of PCDDs-PCDFs and dl-PCBs in their milk. Individual milk samples were collected and analyzed according to standard international procedures. A generalized linear model was used to test potential predictors of pollutant concentration in breast milk: age, exposure to waste fires, cigarette smoking, diet, and residence in high/low risk area (defined at high/low environmental pressure by a specific 2007 WHO report). A Structural Equation Model (SEM) analysis was carried out by taking into account PCDDs-PCDFs and dl-PCBs as endogenous variables and age, waste fires, risk area and smoking as exogenous variables.ResultsAll milk samples were contaminated by PCDDs-PCDFs (8.6 pg WHO-TEQ/98g fat ± 2.7; range 3.8-19) and dl-PCBs (8.0 pg WHO-TEQ/98g fat ± 3.7; range 2.5-24), with their concentrations being associated with age and exposure to waste fires (p < 0.01). Exposure to fires resulted in larger increases of dioxins concentrations in people living in low risk areas than those from high risk areas (p < 0.01).ConclusionsA diffuse human exposure to persistent organic pollutants was observed in the Caserta and Naples areas. Dioxins concentration in women living in areas classified at low environmental pressure in 2007 WHO report was significantly influenced by exposure to burns

Dioxins levels in breast milk of women living in Caserta and Naples : Assessment of environmental risk factors

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Thermotolerant Campylobacter spp. in chicken and bovine meat in Italy: Prevalence, level of contamination and molecular characterization of isolates

Campylobacter species are common foodborne pathogens associated with cases of human gastroenteritis worldwide. A detailed understanding of the prevalence, contamination levels and molecular characteristics of Campylobacter spp. in cattle and chicken, which are likely the most important sources of human contamination, is imperative. A collection of 1243 poultry meat samples (665 chicken breasts and 578 chicken thighs) and 1203 bovine meat samples (689 hamburgers and 514 knife-cut meat preparations) were collected at retail outlets, in randomly selected supermarkets located in different Italian regions during one year. Of these samples, 17.38% of the poultry meat and 0.58% of the bovine meat samples tested positive for Campylobacter, of which 131 were Campylobacter jejuni (57.96%) and 95 were Campylobacter coli (42.03%). Campylobacter isolates were genotyped with the aim of assessing the genetic diversity, population structure, source distribution and Campylobacter transmission route to humans. All isolates were molecularly characterized by pulse field gel electrophoresis (PFGE), and further genotyped using multilocus sequence typing (MLST) and fla-SVR sequencing to gain better insight into the population structure. Antibiotic resistance was also investigate. The highest levels of resistance among chicken strains were observed for ciprofloxacin (88.25%), nalidixic acid (81.45%) and tetracycline (75.6%). PFGE analysis revealed 73 pulsotypes for C. jejuni and 54 pulsotypes for C. coli, demonstrating the existance of different and specific clones circulating in Italy. MLST of C.jejuni isolates mainly clustered in the CC353, CC354, CC21, CC206 and CC443; while C.coli isolates clustered only in CC828. The most common flaA alleles were 287 for C. jejuni and 66 for C. coli. Our study confirms that poultry meat is the main source of Campylobacteriosis, whereas red meat had a low level of contamination suggesting a minor role in transmission. The high presence of Campylobacter in retail chicken meat, paired with its increased resistance to antimicrobials with several multidrug resistance profiles detected, is alarming and represents a persistent threat to public health

Polybrominated dibenzo-p-dioxins and furans (PBDD/Fs) in Italian food: Occurrence and dietary exposure

Human exposure to polychlorinated dioxins and furans (PCDD/Fs) through the dietary pathway is widely recognised and regulations in some regions of the world help to limit food contamination. Similar information on the analogous polybrominated dioxins and furans (PBDD/Fs) is scarce, partly due to the higher threshold to analytical access and unavailability of some standard materials. The analytical methodology developed here determined twelve planar PBDD/F congeners using 13Carbon labelled PBDD/F surrogates and high resolution mass spectrometric detection, and was extensively validated prior to the analysis of a range of commonly consumed Italian foods. The methodology also allowed simultaneous determination of PCDD/Fs and polychlorinated biphenyls (PCBs). The results show that PBDD/Fs occurred in different foods over a range of concentrations from <0.001 pg/g to 4.58 pg/g in fish. The dietary exposure (upper bound) of different Italian population groups, resulting from these occurrence levels was estimated using the toxic equivalency (TEQ) approach that is commonly used for dioxin-like contaminants and ranged from 0.17 to 0.42 pg TEQ/kg bodyweight/day (lower bound – 0.01 pg TEQ/kg bodyweight/day) depending on the population subgroup. Although precautionary, upper bound values may provide a more realistic estimate of toxicity as not all congeners and foods were measured. As expected, children were more highly exposed than adults due to lower body weight. These exposure levels were between a quarter and a third of that arising from the sum of PCDD/Fs and PCBs (0.61 to 1.38 pg WHO-TEQ/kg bodyweight/day), but they contribute to the dioxin-like toxicity. If this data is considered in view of the revised tolerable dioxin-like dietary intake published by EFSA in 2018, it is evident that the tolerable weekly intake of 2 pg/kg bodyweight/week would be exceeded by some of the assessed population sub-groups, or all sub-groups if the cumulative intake is considered

Gastroenteritis Outbreak at Holiday Resort, Central Italy

Gastroenteritis Outbreak at Holiday Resort, Central Ital

Assessment of dietary exposure to some persistent organic pollutants in the Republic of Karakalpakstan of Uzbekistan.

A 1999 study heightened long-standing concerns over persistent organic pollutant contamination in the Aral Sea area, detecting elevated levels in breast milk and cord blood of women in Karakalpakstan (western Uzbekistan). These findings prompted a collaborative research study aimed at linking such human findings with evidence of food chain contamination in the area. An international team carried out analyses of organochlorine and organophosphate pesticides, polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) on samples of 12 foods commonly produced and consumed in Karakalpakstan. Analysis consistently detected long-lasting organochlorine pesticides and their metabolites in all foods of animal origin and in some vegetables such as onions and carrots--two low-cost components of many traditional dishes. Levels of PCBs were relatively low in all samples except fish. Analyses revealed high levels of PCDDs and PCDFs (together often termed "dioxins") in sheep fat, dairy cream, eggs, and edible cottonseed oil, among other foodstuffs. These findings indicate that food traditionally grown, sold, and consumed in Karakalpakstan is a major route of human exposure to several persistent toxic contaminants, including the most toxic of dioxins, 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). Intake estimations demonstrate that consumption of even small amounts of locally grown food may expose consumers to dioxin levels that considerably exceed the monthly tolerable dioxin intake levels set by the World Health Organization. Data presented in this study allow a first assessment of the risk associated with the consumption of certain food products in Karakalpakstan and highlight a critical public health situation

Bacteriophage therapy to reduce colonization of campylobacter jejuni in broiler chickens before slaughter

Campylobacteriosis is the most commonly reported gastrointestinal disease in humans. Campybacter jejuni is the main cause of the infection, and bacterial colonization in broiler chickens is widespread and difficult to prevent, leading to high risk of occurrence in broiler meat. Phage therapy represents an alternative strategy to control Campylobacter in poultry. The aim of this work was to assess the efficacy of two field-isolated bacteriophages against experimental infections with an anti-microbial resistant (AMR) Campylobacter jejuni strain. A two-step phage application was tested according to a specific combination between chickens’ rearing time and specific multiplicities of infections (MOIs), in order to reduce the Campylobacter load in the animals at slaughtering and to limit the development of phage-resistant mutants. In particular, 75 broilers were divided into three groups (A, B and C), and phages were administered to animals of groups B and C at day 38 (Φ 16-izsam) and 39 (Φ 7-izsam) at MOI 0.1 (group B) and 1 (group C). All broilers were euthanized at day 40, and Campylobacter jejuni was enumerated in cecal contents. Reductions in Campylobacter counts were statistically significant in both group B (1 log10 colony forming units (cfu)/gram (gr)) and group C (2 log10 cfu/gr), compared to the control group. Our findings provide evidence about the ability of phage therapy to reduce the Campylobacter load in poultry before slaughtering, also associated with anti-microbial resistance pattern

Outbreak of unusualSalmonella entericaserovar Typhimurium monophasic variant 1,4 [5],12:i:-, Italy, June 2013 to September 2014

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