A Model Behind the Standard Model

In spite of its many successes, the Standard Model makes many empirical assumptions in the Higgs and fermion sectors for which a deeper theoretical basis is sought. Starting from the usual gauge symmetry $u(1) \times su(2) \times su(3)$ plus the 3 assumptions: (A) scalar fields as vielbeins in internal symmetry space \cite{framevec}, (B) the ``confinement picture'' of symmetry breaking \cite{tHooft,Banovici}, (C) generations as ``dual'' to colour \cite{genmixdsm}, we are led to a scheme which offers: (I) a geometrical significance to scalar fields, (II) a theoretical criterion on what scalar fields are to be introduced, (III) a partial explanation of why $su(2)$ appears broken while $su(3)$ confines, (IV) baryon-lepton number (B - L) conservation, (V) the standard electroweak structure, (VI) a 3-valued generation index for leptons and quarks, and (VII) a dynamical system with all the essential features of an earlier phenomenological model \cite{genmixdsm} which gave a good description of the known mass and mixing patterns of quarks and leptons including neutrino oscillations. There are other implications the consistency of which with experiment, however, has not yet been systematically explored. A possible outcome is a whole new branch of particle spectroscopy from $su(2)$ confinement, potentially as rich in details as that of hadrons from colour confinement, which will be accessible to experiment at high energy.Comment: 66 pages, added new material on phenomenology, and some new reference

18th IEEE Real-Time Systems Symposium: Work in Progress Sessions

Dear Colleagues: Following, the success of last year's Work In Progress (WIP) Sessions during RTSS'96, I am pleased to continue that tradition by presenting you 10 excellent WIP reports for RTSS'97. The prime purpose of RTSS WIP sessions is to provide researchers in Academia and Industry an opportunity to discuss their evolving ideas and gather feedback thereon from the real-time community at large. There were 16 submissions for WIP presentations, of which 10 have been accepted for presentation during the symposium and for inclusion in RTSS'97 WIP proceedings. If you would like to reference any article included in the RTSS'97 WIP Proceedings, please note that theses proceedings are published as a Technical Report from Boston University, Computer Science Department (BUCS-TR-97- 021). Many people worked hard to make the idea of holding the WIP sessions a reality. In particular, I would like to thank Kwei-Jay Lin for accommodating the WIP sessions within the busy schedule of RTSS'97. Also, I would like to thank all members of the RTSS'97 Program Committee who helped me review these submissions. Finally, I would like to thank all those who submitted their work to RTSS'97 WIP Sessions. I hope these sessions will prove beneficial, both to the WIP presenters and to RTSS'97 attendees. Azer Bestavros RTSS'97 WIP Chair December 1997.IEEE-CS TC-RT

Diversity of dromedary camel coronavirus HKU23 in African camels revealed multiple recombination events among closely related betacoronaviruses of the Subgenus embecovirus

International audienceGenetic recombination has frequently been observed in coronaviruses. Here, we sequenced multiple complete genomes of dromedary camel coronavirus HKU23 (DcCoV-HKU23) from Nigeria, Morocco, and Ethiopia and identified several genomic positions indicative of cross-species virus recombination events among other betacoronaviruses of the subgenus Embecovirus (Glade A beta-CoVs). Recombinant fragments of a rabbit coronavirus (RbCoV-HKU14) were identified at the hemagglutinin esterase gene position. Homolog fragments of a rodent CoV were also observed at 8.9-kDa open reading frame 4a at the 3' end of the spike gene. The patterns of recombination differed geographically across the African region, highlighting a mosaic structure of DcCoV-HKU23 genomes circulating in dromedaries. Our results highlighted active recombination of coronaviruses circulating in dromedaries and are also relevant to the emergence and evolution of other betacoronaviruses, including Middle East respiratory syndrome coronavirus (MERS-CoV). IMPORTANCE Genetic recombination is often demonstrated in coronaviruses and can result in host range expansion or alteration in tissue tropism. Here, we showed interspecies events of recombination of an endemic dromedary camel coronavirus, HKU23, with other Glade A betacoronaviruses. Our results supported the possibility that the zoonotic pathogen MERS-CoV, which also cocirculates in the same camel species, may have undergone similar recombination events facilitating its emergence or may do so in its future evolution