Optimal social distancing in epidemic control: cost prioritization, adherence and insights into preparedness principles.

The COVID-19 pandemic experience has highlighted the importance of developing general control principles to inform future pandemic preparedness based on the tension between the different control options, ranging from elimination to mitigation, and related costs. Similarly, during the COVID-19 pandemic, social distancing has been confirmed to be the critical response tool until vaccines become available. Open-loop optimal control of a transmission model for COVID-19 in one of its most aggressive outbreaks is used to identify the best social distancing policies aimed at balancing the direct epidemiological costs of a threatening epidemic with its indirect (i.

High-resolution X-ray tomographic workflow to investigate the stress distribution in vitreous enamel steels.

Vitreous enamel steels (VES) are a class of metal-ceramic composite materials realised with a low carbon steel basement coated by an enamel layer. During the firing phase to adhere the enamel to the metal, several gas bubbles remain entrapped inside the enamel volume modifying its internal structure. In this work high-resolution X-ray computed tomography (micro-CT) was used to investigate these composite materials.

Insights into the genetic organization of the Bacillus mycoides cryptic plasmids pDx14.2 and pSin9.7 deduced from their complete nucleotide sequence.

Bacillus mycoides, a member of the Bacillus cereus group of bacteria, can be easily distinguished from close species because of colony shape, made by filaments of cells, resembling fungal hyphae, curving clock- or counterclockwise depending on the strain. Two plasmids, one from a strain curving to the right (pDx14.2), the other from a strain curving to the left (pSin9.

Colony shape as a genetic trait in the pattern-forming Bacillus mycoides.

Background: Bacillus mycoides Flügge, a Gram-positive, non-motile soil bacterium assigned to Bacillus cereus group, grows on agar as chains of cells linked end to end, forming radial filaments curving clock- or counter-clockwise (SIN or DX morphotypes). The molecular mechanism causing asymmetric curving is not known: our working hypothesis considers regulation of filamentous growth as the prerequisite for these morphotypes.

Results: SIN and DX strains isolated from the environment were classified as B.

Molecular analysis of two rolling-circle replicating cryptic plasmids, pBMYdx and pBMY1, from the soil gram-positive Bacillus mycoides.

Two cryptic plasmids of two environmental strains of the soil Bacillus mycoides were cloned and sequenced. They are of a small size (3377 and 3476 bp) and carry regions homologous to double- and single-strand origins of replication of rolling-circle replication modules. In addition, both plasmids have ORFs with homologies with Mob and Rep proteins, in the same relative position and orientation.

The binding sites for Xenopus laevis FIII/YY1 in the first exon of L1 and L14 ribosomal protein genes are dispensable for promoter expression.

The genes coding for the ribosomal proteins (rp genes) L14 and L1 in the toad Xenopus laevis are contacted in the first exon by the frog protein, FIII/YY1, homolog of the human zinc-finger protein YY1, acting as repressor, activator and initiator of transcription. To investigate the functional significance of FIII/YY1 in the context of the two rp genes, the L14 region at nucleotide positions -105 to +44, including all of the first exon was linked to the chloramphenicol acetyltransferase (CAT) reporter gene; constructs with wild-type and mutated sites for FIII/YY1 were injected into nuclei of stage V-VI oocytes and analyzed for CAT activity. The same procedure was followed for constructs made with L1 sequences at nucleotide positions -17 to +1567.

Characterization of FIII/YY1, a Xenopus laevis conserved zinc-finger protein binding to the first exon of L1 and L14 ribosomal protein genes.

The cDNA coding for the Xenopus laevis homolog of the transcriptional activator/repressor protein delta/YY1 was isolated from a lambda gt11 oocyte cDNA library. The deduced aminoacid sequence shows that the four zinc fingers of the DNA binding domain are 99% conserved when compared to the mouse (delta) and 95% to the human (YY1) proteins, while differences are found in the N-terminal region. In particular, the long run of consecutive glycines and histidines of delta and YY1 is missing.