512 research outputs found
Dimensional properties of the harmonic measure for a random walk on a hyperbolic group
International audienceThis paper deals with random walks on isometry groups of Gromov hyperbolic spaces, and more precisely with the dimension of the harmonic measure associated with such a random walk. We first establish a link of the form between the dimension of the harmonic measure, the asymptotic entropy of the random walk and its rate of escape . Then we use this inequality to show that the dimension of this measure can be made arbitrarily small and deduce a result on the type of the harmonic measure
Weighted One-Deterministic-Counter Automata
We introduce weighted one-deterministic-counter automata (ODCA). These are
weighted one-counter automata (OCA) with the property of counter-determinacy,
meaning that all paths labelled by a given word starting from the initial
configuration have the same counter-effect. Weighted ODCAs are a strict
extension of weighted visibly OCAs, which are weighted OCAs where the input
alphabet determines the actions on the counter.
We present a novel problem called the co-VS (complement to a vector space)
reachability problem for weighted ODCAs over fields, which seeks to determine
if there exists a run from a given configuration of a weighted ODCA to another
configuration whose weight vector lies outside a given vector space. We
establish two significant properties of witnesses for co-VS reachability: they
satisfy a pseudo-pumping lemma, and the lexicographically minimal witness has a
special form. It follows that the co-VS reachability problem is in P.
These reachability problems help us to show that the equivalence problem of
weighted ODCAs over fields is in P by adapting the equivalence proof of
deterministic real-time OCAs by B\"ohm et al. This is a step towards resolving
the open question of the equivalence problem of weighted OCAs. Furthermore, we
demonstrate that the regularity problem, the problem of checking whether an
input weighted ODCA over a field is equivalent to some weighted automaton, is
in P. Finally, we show that the covering and coverable equivalence problems for
uninitialised weighted ODCAs are decidable in polynomial time. We also consider
boolean ODCAs and show that the equivalence problem for (non-deterministic)
boolean ODCAs is in PSPACE, whereas it is undecidable for (non-deterministic)
boolean OCAs.Comment: 36 pages, 11 figure
Recombinant immunomodulating lentogenic or mesogenic oncolytic newcastle disease virus for treatment of pancreatic adenocarcinoma
Oncolytic Newcastle disease virus (NDV) might be a promising new therapeutic agent for the treatment of pancreatic cancer. We evaluated recombinant NDVs (rNDVs) expressing interferon (rNDV-hIFNβ-F0) or an IFN antagonistic protein (rNDV-NS1-F0), as well as rNDV with increased virulence (rNDV-F3aa) for oncolytic efficacy in human pancreatic adenocarcinoma cells. Expression of additional proteins did not hamper virus replication or cytotoxic effects on itsel
Serum Midkine, estimated glomerular filtration rate and chronic kidney disease-related events in elderly women: Perth Longitudinal Study of Aging Women
© 2020, The Author(s). Midkine (MDK), a heparin-binding growth factor cytokine, is involved in the pathogenesis of kidney diseases by augmenting leukocyte trafficking and activation. Animal models and small case control studies have implicated MDK as a pathological biomarker in chronic kidney diseases (CKD), however this is yet to be confirmed in prospective human studies. In a prospective study of 499 elderly, predominantly Caucasian women aged over 70 years the association between serum MDK collected in 1998, and renal function change and the risk of CKD-related hospitalisations and deaths at 5 and 14.5 years, respectively, was examined. Baseline serum MDK was not associated with 5-year change in estimated glomerular filtration rate using the CKD Epidemiology Collaboration creatinine and cystatin C equation (Standardised β = − 0.09, 95% confidence interval − 3.76–0.48, p = 0.129), 5-year rapid decline in renal function (odds ratio = 0.97, 95% confidence interval 0.46–2.02, p = 0.927) or the risk of 14.5-year CKD-related hospitalisations and deaths (hazard ratio = 1.27, 95% confidence interval.66–2.46, p = 0.470) before or after adjusting for major risk factors. In conclusion, in this cohort of elderly women with normal or mildly impaired renal function, serum MDK was not associated with renal function change or future CKD-related hospitalisations and deaths, suggesting that MDK may not be an early biomarker for progression of CKD
Thermochromic Metal Halide Perovskite Windows with Ideal Transition Temperatures
Urban centers across the globe are responsible for a significant fraction of
energy consumption and CO2 emission. As urban centers continue to grow, the
popularity of glass as cladding material in urban buildings is an alarming
trend. Dynamic windows reduce heating and cooling loads in buildings by passive
heating in cold seasons and mitigating solar heat gain in hot seasons. In this
work, we develop a mesoscopic building energy model that demonstrates reduced
building energy consumption when thermochromic windows are employed. Savings
are realized across eight disparate climate zones of the United States. We use
the model to determine the ideal critical transition temperature of 20 to 27.5
{\deg}C for thermochromic windows based on metal halide perovskite materials.
Ideal transition temperatures are realized experimentally in composite metal
halide perovskite film composed of perovskite crystals and an adjacent
reservoir phase. The transition temperature is controlled by co-intercalating
methanol, instead of water, with methylammonium iodide and tailoring the
hydrogen-bonding chemistry of the reservoir phase. Thermochromic windows based
on metal halide perovskites represent a clear opportunity to mitigate the
effects of energy-hungry buildings
Investigation of SOA-based wavelength conversion at 80 Gb/s using bandpass filtering
This paper presents a simple and effective 80 Gb/s wavelength conversion scheme by using Cross Gain Modulation in a Semiconductor Optical Amplifiers (SOA) in conjunction with filtering the blue shifted component of the probe spectrum to give a non-inverted output signal
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