EUSO-SPB1 mission and science

The Extreme Universe Space Observatory on a Super Pressure Balloon 1 (EUSO-SPB1) was launched in 2017 April from Wanaka, New Zealand. The plan of this mission of opportunity on a NASA super pressure balloon test flight was to circle the southern hemisphere. The primary scientific goal was to make the first observations of ultra-high-energy cosmic-ray extensive air showers (EASs) by looking down on the atmosphere with an ultraviolet (UV) fluorescence telescope from suborbital altitude (33 km). After 12 days and 4 h aloft, the flight was terminated prematurely in the Pacific Ocean. Before the flight, the instrument was tested extensively in the West Desert of Utah, USA, with UV point sources and lasers. The test results indicated that the instrument had sensitivity to EASs of ⪆ 3 EeV. Simulations of the telescope system, telescope on time, and realized flight trajectory predicted an observation of about 1 event assuming clear sky conditions. The effects of high clouds were estimated to reduce this value by approximately a factor of 2. A manual search and a machine-learning-based search did not find any EAS signals in these data. Here we review the EUSO-SPB1 instrument and flight and the EAS search

Microbiological Evaluation of Carcasses of Wild Boar Hunted in a Hill Area of Northern Italy

This study evaluated the prevalence of potential pathogenic bacteria (mainly Campylobacter spp., but also Listeria monocytogenes and Salmonella) in wild boar (S us scrofa) and the hygiene of carcasses of wild boar hunted in a hill area of northern Italy during a hunting season (October to December). In total, 62 animals were submitted to microbiological analyses of the tonsils (detection of Listeria spp. and Listeria monocytogenes), caecal content (detection of Salmonella and Campylobacter spp.), mesenteric lymph glands (detection of Salmonella), and carcasses. In addition to analyzing pathogen prevalence and carcass hygiene of these animals, we performed an enumeration of total viable count (TVC), Enterobacteriaceae, Escherichia coli, coagulase-positive staphylococci, and spores of sulfite-reducing clostridia. Influencing factors considered were sex, weight, and age of the animals and environmental temperature on the day of hunting. A high prevalence was observed for L. monocytogenes in tonsils (35.3%) and for Campylobacter spp. in caecal content (51.8%), whereas Salmonella enterica strains (mainly serovar Thompson) were only occasionally isolated (7% in caecal content and 3.5% in lymph glands). The prevalence of L. monocytogenes was influenced by animal age and environmental temperature. Campylobacter spp. were the only pathogens detected on the carcasses (16.7%). Carcasses were characterized by low levels of contamination: TVC, 3.21 ± 0.80 log CFU/cm2, Enterobacteriaceae, 1.32 ± 0.89 log CFU/cm2; E. coli, 1.31 ± 0.93 log CFU/cm2; and occasional detection of low counts of staphylococci and clostridia. TVC was positively influenced only by high environmental temperature, and higher Enterobacteriaceae counts were detected on heavy male carcasses than on females. The results confirmed the potential role of wild boars as reservoirs for the most important foodborne pathogens. But a low carcass contamination level is achievable if hunters are properly trained about hygienic carcass management and slaughtering procedures

Pathogenic potential of Listeria monocytogenes isolated from cattle faeces in Adoekiti

Listeria monocytogenes is an opportunistic food-borne pathogen causing listeriosis especially among immune-compromised persons. Its high rate of morbidity and mortality has classed the organism among the top watch list in foods. It is known to produce several virulence factors which aid its survival in harsh conditions and its dissemination within host cells. The pathogenicity of L. monocytogenes, isolated from cattle faeces in Ado-Ekiti, was determined in Wister albino rats for two weeks and the relative virulence was calculated. Rats were challenged with isolates producing listeriolysin O and phospholipase orally, intraperitoneally and subcutaneously. Biochemical parameters and haematoxylin and eosin (H and E) stained sections of selected organs were examined for significant changes (p < .05) and histopathological effects post-experiment. Relative virulence was recorded at 0% with rats showing no signs of infection or death. However, significant changes in total protein, lipid profile and some selected antioxidant enzymes, as well as cytological changes in the examined H and E sections of organs showed that an infection had occurred. Bacteria may have however been eradicated by the immune-competent rats. This study therefore concludes that isolates may be pathogenic especially for persons tagged ‘high risk’ due to low immunity.Keywords:  L. monocytogenes, listeriosis, pathogenicity, histopathology, cattle feace

Revisiting the implications of Liouville's theorem to the anisotropy of cosmic rays

We present a solution to Liouville's equation for an ensemble of charged particles propagating in magnetic fields. The solution is presented using an expansion in spherical harmonics of the phase space density, allowing a direct interpretation of the distribution of arrival directions of cosmic rays. The results are found for chosen conditions of variability and source distributions. We show there are two conditions for an initially isotropic flux of particles to remain isotropic while traveling through a magnetic field: isotropy and homogeneity of the sources. The formalism is used to analyze the data measured by the Pierre Auger Observatory, contributing to the understanding of the dependence of the dipole amplitude with energy and predicting the energy in which the quadrupole signal should be measured

Characterisation of Listeria monocytogenes Isolates from Hunted Game and Game Meat from Finland

Listeria monocytogenes is an important foodborne zoonotic bacterium. It is a heterogeneous species that can be classified into lineages, serogroups, clonal complexes, and sequence types. Only scarce information exists on the properties of L. monocytogenes from game and game meat. We characterised 75 L. monocytogenes isolates from various game sources found in Finland between 2012 and 2020. The genetic diversity, presence of virulence and antimicrobial genes were studied with whole genome sequencing. Most (89%) of the isolates belonged to phylogenetic lineage (Lin) II and serogroup (SG) IIa. SGs IVb (8%) and IIb (3%) of Lin I were sporadically identified. In total, 18 clonal complexes and 21 sequence types (STs) were obtained. The most frequent STs were ST451 (21%), ST585 (12%) and ST37 (11%) found in different sample types between 2012 and 2020. We observed 10 clusters, formed by closely related isolates with 0–10 allelic differences. Most (79%) of the virulence genes were found in all of the L. monocytogenes isolates. Only fosX and lin were found out of 46 antimicrobial resistance genes. Our results demonstrate that potentially virulent and antimicrobial-sensitive L. monocytogenes isolates associated with human listeriosis are commonly found in hunted game and game meat in Finland

Biological characterization, mechanistic investigation and structure‐activity relationships of chemically stable TLR2 antagonists

Toll‐like receptors (TLRs) build the first barrier in the innate immune response and therefore represent promising targets for the modulation of inflammatory processes. Recently, the pyrogallol‐containing TLR2 antagonists CU‐CPT22 and MMG‐11 were reported; however, their 1,2,3‐triphenol motif renders them highly susceptible to oxidation and excludes them from use in extended experiments under aerobic conditions. Therefore, we have developed a set of novel TLR2 antagonists (1 –9 ) based on the systematic variation of substructures, linker elements, and the hydrogen‐bonding pattern of the pyrogallol precursors by using chemically robust building blocks. The novel series of chemically stable and synthetically accessible TLR2 antagonists (1 –9 ) was pharmacologically characterized, and the potential binding modes of the active compounds were evaluated structurally. Our results provide new insights into structure‐activity relationships and allow rationalization of structural binding characteristics. Moreover, they support the hypothesis that this class of TLR ligands bind solely to TLR2 and do not directly interact with TLR1 or TLR6 of the functional heterodimer. The most active compound from this series (6 ), is chemically stable, nontoxic, TLR2‐selective, and shows a similar activity with regard to the pyrogallol starting points, thus indicating the variability of the hydrogen bonding pattern

Observation of a large-scale anisotropy in the arrival directions of cosmic rays above 8 × 10 18 eV

Cosmic rays are atomic nuclei arriving from outer space that reach the highest energies observed in nature. Clues to their origin come from studying the distribution of their arrival directions. Using 3 × 10 4 cosmic rays with energies above 8 × 10 18 electron volts, recorded with the Pierre Auger Observatory from a total exposure of 76,800 km2 sr year, we determined the existence of anisotropy in arrival directions. The anisotropy, detected at more than a 5.2σ level of significance, can be described by a dipole with an amplitude of 6.5 +1.3 -0.9 percent toward right ascension αd = 100 ± 10 degrees and declination δd = -24 +12 -13 degrees. That direction indicates an extragalactic origin for these ultrahighenergy particles.La nómina completa de autores puede verse en el archivo asociado a este ítem.Facultad de Ciencias Exacta

Observation of a large-scale anisotropy in the arrival directions of cosmic rays above 8 × 10 18 eV

Cosmic rays are atomic nuclei arriving from outer space that reach the highest energies observed in nature. Clues to their origin come from studying the distribution of their arrival directions. Using 3 × 10 4 cosmic rays with energies above 8 × 10 18 electron volts, recorded with the Pierre Auger Observatory from a total exposure of 76,800 km2 sr year, we determined the existence of anisotropy in arrival directions. The anisotropy, detected at more than a 5.2σ level of significance, can be described by a dipole with an amplitude of 6.5 +1.3 -0.9 percent toward right ascension αd = 100 ± 10 degrees and declination δd = -24 +12 -13 degrees. That direction indicates an extragalactic origin for these ultrahighenergy particles.La nómina completa de autores puede verse en el archivo asociado a este ítem.Facultad de Ciencias Exacta

Prevalence, virulence and antimicrobial susceptibility of Salmonella spp., Yersinia enterocolitica and Listeria monocytogenes in european wild boar (Sus scrofa) hunted in Tuscany (central Italy)

Wild boar is an animal the population of which constantly increases in Europe. This animal plays an important role as a reservoir for several pathogens, including three of the most important zoonoses: salmonellosis, yersiniosis and listeriosis. The aim of this investigation was to eval-uate the occurrence of antimicrobial-resistant and virulence factor genes of Salmonella spp., Yersinia enterocolitica and Listeria monocytogenes isolated from wild boar in Tuscany (Central Italy). During two consequent hunting seasons (2018/2019 and 2019/2020), rectal swabs, spleens and livers were collected from 287 hunted wild boar to isolate strains. Each isolate was tested to investigate its an-timicrobial resistance and to detect virulence factor genes by PCR. Eighteen Salmonella strains (6.27%) were isolated. Of these, 66.7% were resistant to streptomycin, 13.4% to cephalothin, 6.67% to imipenem and one isolate (6.67%) was resistant simultaneously to five antimicrobials. Moreover, the most detected genes were sopE (73.4%), pipB (66.7%), sodCI (53.3%), spvR and spvC (46.7%). In total, 54 (17.8%) Yersinia enterocolitica were isolated; of them, 26 (48.1%), 9 (16.7%), 17 (31.5%), 1 (1.85%) and 1 (1.85%) belonged to biotypes 1, 2, 3, 4 and 5, respectively. All strains (100%) demon-strated resistance to cephalothin and 70.4% to amoxicillin-clavulanic acid, 55.6% to ampicillin, and 37.0% to cefoxitin. Additionally, the most detected genes were ystA (25.9%), inv (24.1%), ail (22.2%), ystB (18.5%) and virF (14.8%). Finally, only one Listeria monocytogenes isolate (0.35%) was obtained, belonging to serogroup IVb, serovar 4b, and it was found to be resistant to cefoxitin, cefotaxime and nalidixic acid. The results highlighted the role of wild boar as a carrier for pathogenic and antimi-crobial-resistant Salmonella spp., Yersinia enterocolitica and Listeria monocytogens, representing a possible reservoir for domestic animals and human pathogens

Exploring the mechanisms of action of human secretory RNase 3 and RNase 7 against Candida albicans

Human antimicrobial RNases, which belong to the vertebrate RNase A superfamily and are secreted upon infection, display a wide spectrum of antipathogen activities. In this work, we examined the antifungal activity of the eosinophil RNase 3 and the skin-derived RNase 7, two proteins expressed by innate cell types that are directly involved in the host defense against fungal infection. Candida albicans has been selected as a suitable working model for testing RNase activities toward a eukaryotic pathogen. We explored the distinct levels of action of both RNases on yeast by combining cell viability and membrane model assays together with protein labeling and confocal microscopy. Site-directed mutagenesis was applied to ablate either the protein active site or the key anchoring region for cell binding. This is the first integrated study that highlights the RNases' dual mechanism of action. Along with an overall membrane-destabilization process, the RNases could internalize and target cellular RNA. The data support the contribution of the enzymatic activity for the antipathogen action of both antimicrobial proteins, which can be envisaged as suitable templates for the development of novel antifungal drugs. We suggest that both human RNases work as multitasking antimicrobial proteins that provide a first line immune barrier