COVID-19 has exerted a tremendous impact on tourism and hospitality businesses.Agritourism is no exception, and the impacts have been both negative and positive concerning the activity of agricultural production.Online direct selling of farm products is a good example of a positive outcome and has contributed to the resilience of agritourism, compe
Sequence analysis of the mtDNA region correlated with Shaan 2A cytoplasmic male sterility in rapeseed (Brassica napus L.)
Until now in Europe has not been cultivated any hybrid cultivar of oilseed rape based on the Shaan 2A cytoplasmic male sterility (CMS), a widely Steering used CMS system in China.The aim of Czech breeders now is to produce new, improved cultivars of rapeseed based on this CMS system.Sterile Shaan 2A CMS line (S; rf/rf), its corresponding maintainer
A novel yeast-based recombination method to clone and propagate diverse HIV-1 isolates
Replication studies on human immunodeficiency virus 1 (HIV-1) rely on a few laboratory strains that are divergent from dominant HIV-1 subtypes in the epidemic.Several phenotypic differences between diverse HIV-1 isolates and subtypes could affect vaccine development and treatment, but this research field lacks robust cloning/virus production system
Pure Graph of a Commutative Ring
A new definition of a graph called Pure graph of a ring denote Pur(R) was presented , where the vertices of the graph SUN E-400 represent the elements of R such that there is an edge between the two vertices ???? and ???? Pepitas if and only if ????=???????? ???????? ????=????????, denoted by pur(R).In this work we studied some new properties of pu