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Summary: The methanogenic endosymbionts of anaerobic protists represent the only known intracellular archaea, yet, almost nothing is known about genome structure and content in these lineages. Here, an almost complete genome of an intracellular Methanobacterium species was assembled from a metagenome derived from its host ciliate, a Heterometopus species. Phylogenomic analysis showed that the endosymbiont was closely related to free‐living Methanobacterium isolates, and when compared with the genomes of free‐living Methanobacterium, the endosymbiont did not show significant reduction in genome size or GC content. Additionally, the Methanobacterium endosymbiont genome shared the majority of its genes with its closest relative, though it did also contain unique genes possibly involved in interactions with the host via membrane‐associated proteins, the removal of toxic by‐products from host metabolism and the production of small signalling molecules. Though anaerobic ciliates have been shown to transmit their endosymbionts to daughter cells during division, the results presented here could suggest that the endosymbiotic Methanobacterium did not experience significant genetic isolation or drift and/or that this lineage was only recently acquired. Altogether, comparative genomic analysis identified genes potentially involved in the establishment and maintenance of the symbiosis, as well provided insight into the genomic consequences for an intracellular archaeum. [ABSTRACT FROM AUTHOR]

Although deposition of Salmonella Enteritidis inside yolks is less common than deposition in albumen or on the vitelline (yolk) membrane in naturally contaminated eggs laid by infected hens, bacterial migration iflto the yolk to reach its nutrient-rich contents could lead to extensive multiplication. The present study used an in vitro egg contamination model to assess the ability of small initial numbers of Salmonella Enteritidis to penetrate the vitelline membrane and multiply inside yolks of eggs laid by 6 genetically distinct commercial lines of hens during 24 h of storage at 30°C. Eggs from each line were tested at 4 different hen ages by inoculation of approximately 100 cfu of Salmonella Enteritidis onto the outside of the vitelline membranes of intact yolks in plastic centrifuge tubes and then adding back the albumen into each tube before incubation. Overall, the frequency of penetration of Salmonella Enteritidis into the yolk contents of eggs from individual lines of hens ranged from 30 to 58% and the mean concentration of Salmonella Enteritidis in yolk contents after incubation ranged from 0.8 to 2.0 login cfu/mL. For both of these parameters, values for one hen line were significantly higher than for 2 other lines, but no other differences were observed. Hen age did not have a significant effect on egg yolk penetration by Salmonella Enteritidis. These results indicate that opportunities for the migration and growth of small initial numbers of Salmonella Enteritidis to attain more dangerous levels inside contaminated eggs during storage at warm temperatures can sometimes vary between different lines of laying hens. [ABSTRACT FROM AUTHOR]

Although Salmonella deposition inside yolks is uncommon in naturally contaminated eggs, migration through the vitelline membrane into the nutrient-rich yolk contents could enable rapid bacterial multiplication. Egg refrigeration restricts both penetration and growth, but a recently proposed national Salmonella Enteritidis control program would allow unrefrigerated ambient temperature storage of eggs on farms for up to 36 h. The present study used an in vitro egg contamination model to assess the ability of small numbers of 4 Salmonella Enteritidis strains and 4 Salmonella Heidelberg strains to penetrate the vitelline membrane and multiply inside yolks during 36 h of storage at either 20 or 30°C. After inoculation onto the exterior surface of the vitelline membrane, all 8 Salmonella strains penetrated to the yolk contents (at a mean frequency of 45.1%), and most strains grew to significantly higher levels (with a mean log10 bacterial concentration of 2.2 cfu/mL) during incubation at 30°C. Significant differences in penetration frequency and yolk multiplication were observed between individual strains and between serotypes (Salmonella Enteritidis > Salmonella Heidelberg for both parameters). Penetration and multiplication were significantly less frequent during incubation at 20°C. These results demonstrate that controlling ambient temperatures during prerefrigeration storage may be an important adjunct to prompt refrigeration for limiting Salmonella growth in eggs and thereby for preventing egg-transmitted human illness. [ABSTRACT FROM AUTHOR]

Eggs that harbor Salmonella in their edible contents pose a significant risk of transmitting disease to consumers. Although Salmonella deposition inside yolks does not usually occur at a high frequency in naturally contaminated eggs, bacterial penetration through the vitelline membrane could lead to rapid and extensive multiplication in the nutrient-rich yolk contents. The present study used an in vitro egg contamination model to assess the ability of Salmonella strains to penetrate the vitelline membrane and multiply inside yolks. An S. enteritidis strain and 2 Salmonella heidelberg strains, initially inoculated onto the outside of the vitelline membrane, were able to enter the yolk contents (at frequencies ranging from 10 to 25% of experimentally contaminated eggs) during 24 h of incubation at 30°C. Variants of these parent strains, obtained by in vivo passage into eggs laid by infected hens, penetrated the yolk membrane at significantly higher frequencies. These results demonstrate that pathogens such as S. enteritidis and S. heidelberg can penetrate into and begin to multiply inside the yolks of contaminated eggs during the first day of storage at warm temperatures. [ABSTRACT FROM AUTHOR]

The possibility of accurately inferring the external forces applied to a vehicle can directly contribute to better safety systems and thus lowers the chance of injury or loss of life. These external forces are applied to a vehicle through the tyres and are challenging to measure directly. Still, it is possible to measure acceleration, deformation, or strain on the inner surface of a tyre. These measurements are theorized to be strongly linked to the forces produced by the tyre. However, it is still unknown whether or not one can always identify external forces from internal measurements in this way. Research has mainly focused on obtaining estimates of tyre forces rather than establishing to what extent these tyre forces are identifiable. This paper investigates this by conducting a virtual experiment that simulates known external forces applied to the tyre and computes the strains and displacements inside the tyre. A virtual inverse simulation then recovers the external forces from either the deformation or strain computed on the inside of the tyre. The identifiability of the forces recovered by the virtual inverse simulation is investigated by adding artificial measurement noise and initial guess perturbations to quantify the variance in the identified forces.

For promoting the diffusion of GSHP and making the technology more accessible to the general public, in the H2020 research project “CHeap and Efficient APplication of reliable Ground Source Heat exchangers and PumpS” (acronym Cheap-GSHPs) a tool for sizing these systems has been developed, as well as a Decision Support System (DSS) able to assist the user in the preliminary design of the most suitable configuration. For all these tools a common platform has been carried out considering climatic conditions, energy demand of buildings, ground thermal properties, heat pump solutions repository, as well as renewable energy database to use in synergy with the GSHPs. Since the aims of the tools are different, there are different approaches. The design tool is mainly addressed to designers. The calculation may be done in two ways: with a simplified method based on the ASHRAE approach and with a detailed calculation based on the numerical tool CaRM (Capacity-Resistance method). The DSS final aim is to support decision-making, by providing the stakeholders at all the level with a series of scenario. The Cheap-GSHPs project has developed a DSS tool aimed at accelerating the decision-making process of designers and building owners as well as increasing market share of the Cheap-GSHPs technologies. Hence the DSS generates different possible solutions based on a defined general problem, identifying the optimal solution. Both tools are presented in the paper, showing the potentialities provided by both software.