Rectifiable paths with polynomial log-signature are straight lines

The signature of a rectifiable path is a tensor series in the tensor algebra whose coefficients are definite iterated integrals of the path. The signature characterises the path up to a generalised form of reparametrisation. It is a classical result of K. T. Chen that the log-signature (the logarithm of the signature) is a Lie series. A Lie series is polynomial if it has finite degree. We show that the log-signature is polynomial if and only if the path is a straight line up to reparametrisation. Consequently, the log-signature of a rectifiable path either has degree one or infinite support. Though our result pertains to rectifiable paths, the proof uses results from rough path theory, in particular that the signature characterises a rough path up to reparametrisation.Comment: 11 page

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

Anna Friz : The Clandestine Transmissions of Pirate Jenny

This recording by Anna Friz comprises the clandestine transmissions of Pirate Jenny, a fictional character who lives inside a radio and broadcasts at night, hoping to contact someone. The artist introduces the piece and explains that since the sounds in it are taken from the airwaves of Montreal, one can consider it a portrait of the city

There's a Risk of Arrest if You Turn Right

This recording by Friz and Williams explores sound as a site of resistance. The artists introduce the piece and describe the sounds of the protests recorded in Quebec City during the Summit of the Americas as “aural occupations.” In opposition to the singular perspective of the mainstream media, the artists present the space of protest as complex and multi-layered, while furthering the sounds of dissent in radiophonic space

Steve Heimbecker : Songs of Place

"The 2 DVD-Video represent video and surround sound portraits of four places: Halifax (NS), Montréal (QC), Vancouver (BC), and Springwater (SK). In production since 2000, this series was re-mastered for publication in the New Media Lab of Oboro in Montréal, while Steve Heimbecker was in residence in 2004. In the bookwork, five contributors were invited to reflect on the “portraits”: Vincent Bonin, Anna Friz, Christof Migone, F Scott Taylor, and Barry Truax. The artist himself contributes a text, which analyzes his last ten years of research." -- Actuellecd website