Symmetry breaking problems are among the most well studied in the field of distributed computing and yet the most fundamental questions about their complexity remain open. In this paper we work in the LOCAL model (where the input graph and underlying distributed network are identical) and study the randomized complexity of four fundamental symmetry breaking problems on graphs: computing MISs (maximal independent sets), maximal matchings, vertex colorings, and ruling sets. A small sample of our results includes• An MIS algorithm running in O(log 2 ∆ + 2 O( √ log log n) ) time, where ∆ is the maximum degree. This is the first MIS algorithm to improve on the 1986 algorithms of Luby and Alon, Babai, and Itai, when log n ∆ 2 √ log n , and comes close to the Ω(log ∆) lower bound of Kuhn, Moscibroda, and Wattenhofer.• A maximal matching algorithm running in O(log ∆ + log 4 log n) time. This is the first significant improvement to the 1986 algorithm of Israeli and Itai. Moreover, its dependence on ∆ is provably optimal. • A (∆ + 1)-coloring algorithm requiring O(log ∆ + 2 O( IntroductionBreaking symmetry is one of the central themes in the theory of distributed computing. At initialization the nodes of a distributed system are assumed to be in the same state, possibly with distinct * A preliminary version of this paper appeared in the

We analyzed p53 cDNA and genomic clones from a variety of normal and transformed cells. Sequence analysis of these clones revealed that amino acid residue 72 can be an arginine, proline, or cysteine. This single codon difference results in electrophoretically distinct forms of human p53 seen in normal and transformed cells.

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Regulations to contain the spread of COVID-19 have affected corporations, institutions, and individuals to a degree that most people have never seen before. Information systems researchers have initiated a discourse on information technology's role in helping people manage this situation. This study informs and substantiates this discourse based on an analysis of a rich dataset: Starting in March 2020, we collected about 3 million tweets that document people's use of web-conferencing systems (WCS) like Zoom during the COVID-19 crisis. Applying text-mining techniques to Twitter data and drawing on affordance theory, we derive five affordances of and five constraints to the use of WCS during the crisis. Based on our analysis, our argument is that WCS emerged as a social technology that led to a new virtual togetherness by facilitating access to everyday activities and contacts that were "locked away" because of COVID-19-mitigation efforts. We find that WCS facilitated encounters that could not have taken place otherwise and that WCS use led to a unique blending of various aspects of people's lives. Using our analysis, we derive implications and directions for future research to address existing constraints and realise the potentials of this period of forced digitalisation.

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