Hopf bifurcations of twisted states in phase oscillators rings with nonpairwise higher-order interactions

Synchronization is an essential collective phenomenon in networks of interacting oscillators. Twisted states are rotating wave solutions in ring networks where the oscillator phases wrap around the circle in a linear fashion. Here, we analyze Hopf bifurcations of twisted states in ring networks of phase oscillators with nonpairwise higher-order interactions. Hopf bifurcations give rise to quasiperiodic solutions that move along the oscillator ring at nontrivial speed. Because of the higher-order interactions, these emerging solutions may be stable. Using the Ott–Antonsen approach, we continue the emergent solution branches which approach anti-phase type solutions (where oscillators form two clusters whose phase is π apart) as well as twisted states with a different winding number

Hopf Bifurcations of Twisted States in Phase Oscillators Rings with Nonpairwise Higher-Order Interactions

Synchronization is an essential collective phenomenon in networks of interacting oscillators. Twisted states are rotating wave solutions in ring networks where the oscillator phases wrap around the circle in a linear fashion. Here, we analyze Hopf bifurcations of twisted states in ring networks of phase oscillators with nonpairwise higher-order interactions. Hopf bifurcations give rise to quasiperiodic solutions that move along the oscillator ring at nontrivial speed. Because of the higher-order interactions, these emerging solutions may be stable. Using the Ott--Antonsen approach, we continue the emergent solution branches which approach anti-phase type solutions (where oscillators form two clusters whose phase is $\pi$ apart) as well as twisted states with a different winding number.Comment: 24 pages, 8 figure

Using a Logic Programming Framework to Control Database Query Dialogues in Natural Language

We present a natural language question/answering system to interface the University of Évora databases that uses clarification dialogs in order to clarify user questions. It was developed in an integrated logic programming framework, based on constraint logic programming using the GnuProlog(-cx) language [2,11] and the ISCO framework [1]. The use of this LP framework allows the integration of Prolog-like inference mechanisms with classes and inheritance, constraint solving algorithms and provides the connection with relational databases, such as PostgreSQL. This system focus on the questions’ pragmatic analysis, to handle ambiguity, and on an efficient dialogue mechanism, which is able to place relevant questions to clarify the user intentions in a straightforward manner. Proper Nouns resolution and the pp-attachment problem are also handled. This paper briefly presents this innovative system focusing on its ability to correctly determine the user intention through its dialogue capability

Metabolic Versatility in Melainabacteria, a Close Relative of Cyanobacteria

A New Member of Melainabacteria, the Closest Relatives of Cyanobacteria Melainabacteria are the recently discovered, closest non-photosynthetic relatives of cyanobacteria, the organisms responsible for the oxygenation of Earth\u27s atmosphere. Previous work has shown that Melainabacteria live in a wide range of environments, including deep groundwater, anoxic sediments, and the digestive tracts of termites and mammals. These bacteria have been suggested to play a significant role in the latter environments and may contribute to neurodegenerative and gastrointestinal disease in human populations. However, our knowledge of Melainabacteria diversity and metabolism is still very limited, principally because no member of this group has been successfully cultured in the laboratory. Recently, DNA sequencing has revealed that a member of the Melainabacteria is growing in co-culture with an established diatom strain at the University of Montana’s Miller lab. In this study, we obtained a nearly complete Melainabacteria genome from metagenomic sequencing data. We then compared this genome to other previously sequenced Melainabacteria genomes to better understand genome architecture and the metabolic capacity of this bacterium. These data will guide further culturing efforts and future experiments. Together, our work will help clarify the functional role(s) of Melainabacteria in its environment and how it “makes a living” energetically. It will also provide new insights regarding the metabolic capabilities of the cyanobacterial ancestor and the origin of oxygenic photosynthesis

Jury deliberation: An observation study.

In this article, the way that the jury works is considered from a group-analytic perspective. Observational fieldwork of simulated jury deliberations is presented. The data was gathered from a joint funded Home Office and Law Commission project at the Socio- Legal Studies Centre, Oxford in 1995. Inferences are drawn from the observations and the unconscious group processes are considered. The efficacy of the jury process is discussed

The Lorentzian distance formula in noncommutative geometry

For almost twenty years, a search for a Lorentzian version of the well-known Connes' distance formula has been undertaken. Several authors have contributed to this search, providing important milestones, and the time has now come to put those elements together in order to get a valid and functional formula. This paper presents a historical review of the construction and the proof of a Lorentzian distance formula suitable for noncommutative geometry.Comment: 16 pages, final form, few references adde

Cloning of a cDNA coding for an amino acid carrier from Ricinus communis (RcAAP1) by functional complementation in yeast: kinetic analysis, inhibitor sensitivity and substrate specificity

AbstractA cDNA for the amino acid permease gene RcAAP1 has been isolated from Ricinus communis by yeast complementation and subjected to a detailed kinetic analysis. RcAAP1 cDNA is 1.5 kb with an open reading frame that codes for a protein with 486 amino acids and a calculated molecular mass of 53.1 kDa. RcAAP1-mediated histidine uptake was pH dependent with highest transport rates at acidic pH; it was sensitive to protonophores and uncouplers and the Km for histidine uptake was 96 μM. The substrate specificity was investigated by measuring the levels of inhibition of histidine uptake by a range of amino acids. The basic amino acids (histidine, lysine and arginine) showed strongest inhibition of uptake whereas acidic amino acids competed less effectively. Alanine was the most efficient competitor of the neutral amino acids. Glutamine, serine, asparagine, methionine and cysteine showed moderate inhibition whereas threonine, isoleucine, leucine, phenylalanine, tyrosine and tryptophan showed only low levels of inhibition. Glycine, proline and citrulline caused slight stimulation. More detailed competition kinetics indicated that both lysine and arginine showed simple competitive inhibition of histidine uptake. When direct uptake measurements were carried out, both lysine and arginine were found to be effective substrates for RcAAP1