To date, viruses closely related to SARS-CoV-2 have been reported in four bat species: Rhinolophus acuminatus, Rhinolophus affinis, Rhinolophus malayanus, and Rhinolophus shameli. Here, we analysed 343 sequences of the mitochondrial cytochrome c oxidase subunit 1 gene (CO1) from georeferenced bats of the four Rhinolophus species identified as reservoirs of SARS-CoV-2-like viruses. Haplotype networks were constructed in order to investigate patterns of genetic diversity among bat populations of Southeast Asia. No strong geographic structure was found for the four Rhinolophus species, suggesting high dispersal capacity. The ecological niche of SARS-CoV-2 like viruses was predicted using the four localities of bat SARS-CoV-2-like viruses and the localities where bats showed identical or very similar CO1 haplotypes than virus-positive bats. The ecological niche of SARS-CoV-like viruses was deduced from the localities where bat SARS-CoV-like viruses were previously detected. The results show that the ecological niche of SARS-CoV2-like viruses includes several regions of mainland Southeast Asia whereas that of SARS-CoV-like viruses is mainly restricted to China. In agreement with these results, human populations in Laos, Vietnam, Cambodia, and Thailand appear to be much less affected by the Covid-19 pandemic than other countries of Southeast Asia. In the climatic transitional zone between the two ecological niches (southern Yunnan, northern Laos, northern Vietnam, and possibly Hainan and Taiwan), genomic recombination between highly divergent viruses is more likely to occur. Since recombinant viruses can threaten the benefit of vaccination campaigns, these regions should be under surveillance.

This paper first discusses a fractional-order Liu system of order as low as 2.7 and shows its chaotic characteristics by carrying out numerical simulations such as Lyapunov exponents, bifurcation diagrams and phase portraits. Then, by using the topological horseshoe theory and computer-assisted proof, the existence of chaos in the system is verified theoretically. Finally, the fractional-order system is implemented on a Field Programmable Gate Array (FPGA) and the results obtained show that the fractional-order Liu system is indeed chaotic.

Well-intentioned regulations to protect Canada’s most productive farmland restrict large-scale so-lar photovoltaic (PV) development. The recent innovation of agrivoltaics, which is the co-development of land for both PV and agriculture, makes these regulations obsolete. Burgeoning agrivoltaics research has shown agricultural benefits including increased yield for a wide range of crops, plant protection from excess solar energy and hail, improved water conservation while maintaining agricultural employment and local food supplies. In addition, the renewable electricity generation decreases greenhouse gas emissions while increasing farm revenue. As Canada in general, and Ontario in particular, is at a strategic disadvantage in agricultural without agrivoltaics, this study investigates the policy changes necessary to capitalize on the benefits of using agrivoltaics in Ontario. Land use policies in Ontario are reviewed. Then, three case studies (peppers, sweet corn and winter wheat) are analyzed for agrivoltaic potential in Ontario. These results are analyzed in conjunction with potential policies that would continue to protect the green-belt of the Golden Horseshoe, while enabling agrivoltaics in Ontario. Four agrivoltaic policy areas are discussed: increased research and development, enhanced education/public awareness, mechanisms to support Canada’s farmers converting to agrivoltaics and using agrivoltaics as a potential source of trade surplus with the U.S.

Horseshoe crabs represent the most ancestral chelicerate lineage characterized by marine ecology and the possession of lateral compound eyes. While considered living fossils, recent studies reported an unusual number of Pax6 transcription factor genes in the Atlantic horseshoe crab Limulus polyphemus. Pax genes encode a family of ancient metazoan transcription factors, which comprise seven subfamilies. Among these, the members of the Pax6 subfamily confer critical functions in the development of the head, the visual system, and further body plan components. Arthropods are characterized by two Pax6 subfamily homologs that were discovered in Drosophila and named eyeless (ey) and twin of eyeless (toy). However, whole genome sequence searches uncovered three homologs of ey and two homologs of toy in L. polyphemus. These numbers are explained by the occurrence of three whole genome duplications (WGD) in the lineage to the last common ancestor of L. polyphemus and its closely related three additional members of the extant horseshoe crab species cluster. Here we report comparative sequence evidence for the functional conservation of the five L. polyphemus Pax6 transcription factor homologs. Our analyses reveal that all paralogs are conserved in the approximately 135 million-year-old horseshoe crab species cluster and that they evolve under strong purifying selection. These findings identify subfunctionalization as the likeliest post-WGD outcome for the five Pax6 homologs. While awaiting confirmation by gene expression studies, this scenario would reconcile the discrepancy between the WGD-expanded gene repertoires and phenotypic stasis in the horseshoe crabs.