Aggregative oviposition varies with density in processionary moths—Implications for insect outbreak propensity

1. In gregarious insects, groups commonly originate from females laying eggs in masses and feeding groups are established as soon as larvae hatch. Some groupliving insect species may aggregate beyond the individual parent level, such that offspring from two or more egg masses develop within a common resource. 2. Here we show that aggregative oviposition can vary with population density at oviposition and possibly be an important factor in outbreak dynamics of phytophagous insects. 3. We analysed density data with respect to egg mass aggregation for two species of pine processionary moths, Thaumetopoea pinivora (in Sweden 2005–2019) and T. pityocampa (in Spain 1973–1991). Both species lay their eggs in egg masses and feed in groups. During the study periods, insect population density for both species varied by at least an order of magnitude. 4. The two species showed strikingly similar patterns of egg mass aggregation. Egg masses were overdispersed at high population density, with few trees showing a high load of egg masses. 5. Our data suggest that aggregative oviposition can be important in explaining the previously documented higher propensity for outbreaks in insects laying eggs in clusters, compared with those laying individual eggs.European Union's Horizon 2020 Program for Research and Innovation 771271Spanish Governmen

New technology based on clamping for high gradient radio frequency photogun

High gradient rf photoguns have been a key development to enable several applications of high quality electron beams. They allow the generation of beams with very high peak current and low transverse emittance, satisfying the tight demands for free-electron lasers, energy recovery linacs, Compton/Thomson sources and high-energy linear colliders. In the present paper we present the design of a new rf photogun recently developed in the framework of the SPARC_LAB photoinjector activities at the laboratories of the National Institute of Nuclear Physics in Frascati (LNF-INFN, Italy). This design implements several new features from the electromagnetic point of view and, more important, a novel technology for its realization that does not involve any brazing process. From the electromagnetic point of view the gun presents high mode separation, low peak surface electric field at the iris and minimized pulsed heating on the coupler. For the realization, we have implemented a novel fabrication design that, avoiding brazing, strongly reduces the cost, the realization time and the risk of failure. Details on the electromagnetic design, low power rf measurements and high power radiofrequency and beam tests performed at the University of California in Los Angeles (UCLA) are discussed in the paper

School-age vaccination, school openings and Covid-19 diffusion

This article investigates the relationship between school openings and Covid-19 diffusion when school-age vaccination becomes available. The analysis relies on a unique geo-referenced high frequency database on age of vaccination, Covid-19 cases and hospitalization indicators from the Italian region of Sicily. The study focuses on the change of Covid-19 diffusion after school opening in a homogeneous geographical territory (i.e., with the same control measures and surveillance systems, centrally coordinated by the Regional Government). The identification of causal effects derives from a comparison of the change in cases before and after school opening in the school year 2020/21, when vaccination was not available, and in 2021/22, when the vaccination campaign targeted individuals of age 12-19 and above 19. Results indicate that, while school opening determined an increase in the growth rate of Covid-19 cases in 2020/2021, this effect has been substantially reduced by school-age vaccination in 2021/2022. In particular, we find that an increase of approximately 10% in the vaccination rate of school-age population reduces the growth rate of Covid-19 cases after school opening by approximately 1%

On the effect of the temperature-humidity index on buffalo bulk milk composition and coagulation traits

Little is known about the effects of high levels of environmental temperature and humidity on milk yield and quality in buffaloes since this species is known to be more heat tolerant than cattle. However, the distribution of sweat glands and the dark skin color can negatively affect heat tolerance. Moreover, due to increased global temperatures, concerns regarding heat stress and thermoregulation in dairy animals, including buffaloes, have been extended to the northern hemisphere. In this study, the effects of both the temperature-humidity index (THI) and the maximum daily temperature-humidity index (MTHI) were estimated on bulk milk traits, namely fat, protein, lactose, urea content, pH levels, somatic cell score, coagulation properties, and bacteria count. The dataset consisted of repeated data from 99 Mediterranean water buffalo farms, and mixed models were used for the analyses. Supporting the negative correlations observed, bulk milk fat, protein, and lactose content were significantly lower when THI and MTHI were higher. Similarly, milk pH was lower when THI and MTHI were high; however, high levels of THI or MTHI seemed to not be markedly associated with the milk’s coagulation ability. According to both analysis of variance and correlations, the somatic cell score was not significantly affected by the THI and MTHI. This is the first study based on a large dataset that evaluates the impact of high temperature and humidity in Italian buffalo milk and that provides correlations with traits of interest for the dairy industry, i.e., milk acidity and coagulation ability. In general, findings show that the effects of elevated THI and heat stress on bulk milk quality in buffalo is less evident than in cattle. These preliminary results intend to open debate on the issue of heat stress in dairy buffaloes that are reared in temperate regions. Further studies should focus on individual milk and performance and should investigate the relationship between high THI and buffalo fertility, behavior, and welfare

Characterization of Salmonella Occurring at High Prevalence in a Population of the Land Iguana Conolophus subcristatus in Galapagos Islands, Ecuador

The aim of the study was to elucidate the association between the zoonotic pathogen Salmonella and a population of land iguana, Colonophus subcristatus, endemic to Galápagos Islands in Ecuador. We assessed the presence of Salmonella subspecies and serovars and estimated the prevalence of the pathogen in that population. Additionally, we investigated the genetic relatedness among isolates and serovars utilising pulsed field gel electrophoresis (PFGE) on XbaI-digested DNA and determined the antimicrobial susceptibility to a panel of antimicrobials. The study was carried out by sampling cloacal swabs from animals (n = 63) in their natural environment on in the island of Santa Cruz. A high prevalence (62/63, 98.4%) was observed with heterogeneity of Salmonella subspecies and serovars, all known to be associated with reptiles and with reptile-associated salomonellosis in humans. Serotyping revealed 14 different serovars among four Salmonella enterica subspecies: S. enterica subsp. enterica (n = 48), S. enterica subsp. salamae (n = 2), S. enterica subsp. diarizonae (n = 1), and S. enterica subsp. houtenae (n = 7). Four serovars were predominant: S. Poona (n = 18), S. Pomona (n = 10), S. Abaetetuba (n = 8), and S. Newport (n = 5). The S. Poona isolates revealed nine unique XbaI PFGE patterns, with 15 isolates showing a similarity of 70%. Nine S. Pomona isolates had a similarity of 84%. One main cluster with seven (88%) indistinguishable isolates of S. Abaetetuba was observed. All the Salmonella isolates were pan-susceptible to antimicrobials representative of the most relevant therapeutic classes. The high prevalence and absence of clinical signs suggest a natural interaction of the different Salmonella serovars with the host species. The interaction may have been established before any possible exposure of the iguanas and the biocenosis to direct or indirect environmental factors influenced by the use of antimicrobials in agriculture, in human medicine or in veterinary medicine

Could β-hemolytic, group B Enterococcus faecalis be mistaken for Streptococcus agalactiae?

AbstractA β-hemolytic Enterococcus faecalis strain agglutinating Lancefield group A, B, C, D, F, and G antisera was observed from a rectovaginal swab, in the context of antenatal screening for Streptococcus agalactiae (group B Streptococcus [GBS]). This is the first multi-Lancefield antisera-agglutinating isolate of this species, and it raised particular concern, as it may mimic GBS, leading to false reporting and useless receipt of intrapartum antibiotics

Molecular Epidemiology of mcr-Encoded Colistin Resistance in Enterobacteriaceae From Food-Producing Animals in Italy Revealed Through the EU Harmonized Antimicrobial Resistance Monitoring

Colistin resistance by mobilisable mcr genes has been described in bacteria of food-animal origin worldwide, which has raised public health concerns about its potential foodborne transmission to human pathogenic bacteria. Here we provide baseline information on the molecular epidemiology of colistin-resistant, mcr-positive Escherichia coli and Salmonella isolates in food-producing animals in Italy in 2014-2015. A total 678, 861 and 236 indicator E. coli, Extended Spectrum Beta-Lactamase (ESBL)/AmpC-producing E. coli, and Salmonella isolates, respectively, were tested for colistin susceptibility. These isolates were collected according to the EU harmonized antimicrobial resistance monitoring program and are representative of at least 90 and 80% of the Italian poultry (broiler chickens and turkeys) and livestock (pigs and bovines < 12 months) production, respectively. Whole genome sequencing by Illumina technology and bioinformatics (Center for Genomic Epidemiology pipeline) were used to type 42 mcr-positive isolates by PCR. Colistin resistance was mainly observed in the ESBL/AmpC E. coli population, and was present in 25.9, 5.3, 6.5, and 3.9% of such isolates in turkeys, broilers, pigs, and bovines, respectively. Most colistin-resistant isolates (141/161, 87.5%) harbored genes of the mcr-1 group. mcr-1 was also detected in a small proportion of Salmonella isolates (3/146, 2.0%) in turkeys. Additional mcr types were mcr-3 in four ESBL-producing E. coli from bovines, and two mcr-4 in ESBL (n = 1) and indicator E. coli (n = 1) from pigs and bovines. We describe notable diversity of mcr variants with predominance of mcr-1.1 and mcr-1.2 on conjugative IncX4 plasmids in E. coli and in Salmonella serovars Typhimurium, Newport, Blockley from turkey. A new variant, mcr-1.13 was detected in the chromosome in E. coli in turkey and pig isolates. Additionally, we describe mcr-3.2 and mcr-4.3 in E. coli from bovines, and mcr-4.2 in E. coli from pigs. These findings elucidate the epidemiology of colistin resistance in food-producing animals in Italy along with its genetic background, and highlight the likelihood of mcr horizontal transfer between commensal bacteria and major food-borne pathogens (Salmonella) within the same type of productions. Thorough action and strategies are needed in order to mitigate the risk of mcr transfer to humans, in a “One Health” perspective

Niemann-Pick type C disease mutations of NPC1 gene and evidence of abnormal expression of some mutant alleles in fibroblasts

We analyzed Niemann-Pick type C disease 1 (NP44406) gene in 12 patients with Niemann-Pick type C disease by sequencing both cDNA obtained from fibroblasts and genomic DNA. All the patients were compound heterozygotes. We found 15 mutations, eight of which previously unreported. The comparison of cDNA and genomic DNA revealed discrepancies in some subjects. In two unrelated patients carrying the same mutations (P474L and nt 2972del2) only one mutant allele (P474L), was expressed in fibroblasts. The mRNA corresponding to the other allele was not detected even in cells incubated with cycloheximide. The promoter variants (−1026T/G and −1186T/C or −238 C/G), found to be in linkage with 2972del2 allele do not explain the lack of expression of this allele, as they were also found in control subjects. In another patient, (N1156S/Q922X) the N1156S allele was expressed in fibroblasts while the expression of the other allele was hardly detectable. In a fourth patient cDNA analysis revealed a point mutation in exon 20 (P1007A) and a 56 nt deletion in exon 22 leading to a frameshift and a premature stop codon. The first mutation was confirmed in genomic DNA; the second turned out to be a T→G transversion in exon 22, predicted to cause a missense mutation (V1141G). In fact, this transversion generates a donor splice site in exon 22, which causes an abnormal pre-mRNA splicing leading to a partial deletion of this exon. In some NPC patients, therefore, the comparison between cDNA and genomic DNA may reveal an unexpected expression of some mutant alleles of NPC1 gene

Design, realization, and high power test of high gradient, high repetition rate brazing-free S -band photogun

In this paper, we address the energy spread and slice energy spread of an externally injected electron beam in plasma wakefield accelerators operating in the linear or quasilinear regime. The energy spread is first derived taking into account the phase dependence of the wakefield along the finite-length bunch together with the dephasing during acceleration and found to be strongly dependent on the bunch length. This could be compensated by the beam loading effect, the energy spread from which is then derived and found to be nearly independent of the bunch length. However, the transverse dependence of the beam loading effect also makes the particles at the same longitudinal position experience different accelerating fields, introducing a significant slice energy spread. To estimate the slice energy spread, a theoretical analysis was conducted by taking the transverse betatron motion into account. As a study case, 3D simulations for the 5 GeV laser-plasma acceleration stage of the European Plasma Research Accelerator with eXcellence in Applications project have been performed. Careful optimization of the parameters allows one to obtain an energy spread of ≤1% and a slice energy spread of ≤0.1%, with good agreement between theories and simulations