Search results for "threshold"
showing 10 items of 688 documents
Serum uric acid levels threshold for mortality in diabetic individuals: The URic acid Right for heArt Health (URRAH) project
2022
Background and aim: The URRAH (URic acid Right for heArt Health) Study has identified cut-off values of serum uric acid (SUA) predictive of total mortality at 4.7 mg/dl, and cardiovascular (CV) mortality at 5.6 mg/dl. Our aim was to validate these SUA thresholds in people with diabetes. Methods and results: The URRAH subpopulation of people with diabetes was studied. All-cause and CV deaths were evaluated at the end of follow-up. A total of 2570 diabetic subjects were studied. During a median follow-up of 107 months, 744 deaths occurred. In the multivariate Cox regression analyses adjusted for several confounders, subjects with SUA ≥5.6 mg/dl had higher risk of total (HR: 1.23, 95%CI: 1.04-…
$(BV,L^p)$-decomposition, $p=1,2$, of Functions in Metric Random Walk Spaces
2019
In this paper we study the $(BV,L^p)$-decomposition, $p=1,2$, of functions in metric random walk spaces, a general workspace that includes weighted graphs and nonlocal models used in image processing. We obtain the Euler-Lagrange equations of the corresponding variational problems and their gradient flows. In the case $p=1$ we also study the associated geometric problem and the thresholding parameters.
Tensor product multiresolution analysis with error control for compact image representation
2002
A class of multiresolution representations based on nonlinear prediction is studied in the multivariate context based on tensor product strategies. In contrast to standard linear wavelet transforms, these representations cannot be thought of as a change of basis, and the error induced by thresholding or quantizing the coefficients requires a different analysis. We propose specific error control algorithms which ensure a prescribed accuracy in various norms when performing such operations on the coefficients. These algorithms are compared with standard thresholding, for synthetic and real images.
Dual-kind Q-switching of erbium fiber laser
2014
Two different regimes of Q-switching in the same implementation of an actively Q-switched erbium-doped fiber laser are demonstrated. Depending on the active fiber length and repetition rate of an intracavity Q-cell (acousto-optic modulator), the laser operates either in the regime of common, rather long and low-power, pulses composed of several sub-pulses or in the one of very short and powerful stimulated Brillouin scattering-induced pulses. The basic physical reason of the laser system to oscillate in one of these two regimes is the existence or absence of CW narrow-line “bad-cavity” lasing in the intervals when the Q-cell is blocked.
Automated analysis of images for molecular quantification in immunohistochemistry.
2018
The quantification of the expression of different molecules is a key question in both basic and applied sciences. While protein quantification through molecular techniques leads to the loss of spatial information and resolution, immunohistochemistry is usually associated with time-consuming image analysis and human bias. In addition, the scarce automatic software analysis is often proprietary and expensive and relies on a fixed threshold binarization. Here we describe and share a set of macros ready for automated fluorescence analysis of large batches of fixed tissue samples using FIJI/ImageJ. The quantification of the molecules of interest are based on an automatic threshold analysis of im…
Conditions for the spread of conspicuous warning signals: A numerical model with novel insights
2007
The initial evolution of conspicuous warning signals presents an evolutionary problem because selection against rare conspicuous signals is presumed to be strong, and new signals are rare when they first arise. Several possible solutions have been offered to solve this apparent evolutionary paradox, but disagreement persists over the plausibility of some of the proposed mechanisms. In this paper, we construct a deterministic numerical simulation model that allows us to derive the strength of selection on novel warning signals in a wide range of biologically relevant situations. We study the effects of predator psychology (learning, rate of mistaken attacks, and neophobia) on selection. We a…
Work places with stipend programme and its impact on poverty risk decrease: Case of Latvia
2012
The aim of the paper is to analyze theoretical concepts of poverty risk and to estimate the impact of the Workplaces with Stipend Programme (hereinafter WWS) on poverty risk decrease in Latvia. In order to assess the effects of the WWS three different surveys were carried out: of households with WWS participants, of experts in Latvian labour market issues, and of municipality representatives. The results were analyzed, together with analysis of statistical data. The paper concludes that in general the WWS has a very positive impact on WWS participants? household budgets (more than 95% of the WWS participants in all Latvian regions noted a significant impact of the WWS on their household bud…
Romanian Households Dealing with Precariousness: A life-course approach
2016
This paper addresses the main pathways through which households avoid slipping into poverty in Romania by employing a life-course approach. Recent researches on social stratification found that in every country we can delineate a particular social layer composed of households living just above the poverty threshold, whose members struggle to reach a more secure prosperity while facing constant threats of downward mobility. Drawing on recent precarious prosperity research, and based on in-depth interviews carried out in 2013 with 25 households situated in between poverty and prosperity from a Romanian city (Cluj-Napoca), we use a life-course approach in order to account for the main routes i…
From custom to law, an economic rationale behind the black lettering
2018
This article employs the number of rule recipients in order to explain the transformation of some customs into laws. The publication of rules may mark the reaching of the threshold number beyond which the spontaneous rule leaves room for the State intervention. In addition, the publication resolves a couple of questions that Hayek left unresolved. Examples are provided from ancient merchant customs and contemporary international law.
A critical empirical study of three electricity spot price models
2012
We conduct an empirical analysis of three recently proposed and widely used models for electricity spot price process. The first model, called the jump-diffusion model, was proposed by Cartea and Figueroa (2005), and is a one-factor mean-reversion jump-diffusion model, adjusted to incorporate the most important characteristics of electricity prices. The second model, called the threshold model, was proposed by Roncoroni (2002) and further developed by Geman and Roncoroni (2006), and is an exponential Ornstein–Uhlenbeck process driven by a Brownian motion and a state-dependent compound Poisson process. It is designed to capture both statistical and pathwise properties of electricity spot pri…