Search results for " coherence"
showing 10 items of 429 documents
In Vitro Measurement of Strain Localization Preceding Dissection of the Aortic Wall Subjected to Radial Tension
2020
AbstractBackgroundAortic dissection (AD) is a common pathology and challenging clinical problem. A better understanding of the biomechanical effects preceding its initiation is essential for predicting adverse events on a patient-specific basis. Moreover, the predictability of patient-specific biomechanics-based computational models is hampered by uncertainty about boundary conditions and material properties.ObjectivePredisposition of thoracic aortic aneurysms (TAA) to ADs can be related to the degradation of biomechanically important constituents in the aortic wall of TAAs. The goal of the present study is to develop a new methodology to measure strain fields in aortic tissues subjected to…
Quasi Conjunction and Inclusion Relation in Probabilistic Default Reasoning
2011
We study the quasi conjunction and the Goodman & Nguyen inclusion relation for conditional events, in the setting of probabilistic default reasoning under coherence. We deepen two recent results given in (Gilio and Sanfilippo, 2010): the first result concerns p-entailment from a family F of conditional events to the quasi conjunction C(S) associated with each nonempty subset S of F; the second result, among other aspects, analyzes the equivalence between p-entailment from F and p-entailment from C(S), where S is some nonempty subset of F. We also characterize p-entailment by some alternative theorems. Finally, we deepen the connections between p-entailment and the Goodman & Nguyen inclusion…
Homotopy limits for 2-categories
2008
AbstractWe study homotopy limits for 2-categories using the theory of Quillen model categories. In order to do so, we establish the existence of projective and injective model structures on diagram 2-categories. Using these results, we describe the homotopical behaviour not only of conical limits but also of weighted limits. Finally, pseudo-limits are related to homotopy limits.
Conditional Random Quantities and Iterated Conditioning in the Setting of Coherence
2013
We consider conditional random quantities (c.r.q.’s) in the setting of coherence. Given a numerical r.q. X and a non impossible event H, based on betting scheme we represent the c.r.q. X|H as the unconditional r.q. XH + μH c , where μ is the prevision assessed for X|H. We develop some elements for an algebra of c.r.q.’s, by giving a condition under which two c.r.q.’s X|H and Y|K coincide. We show that X|HK coincides with a suitable c.r.q. Y|K and we apply this representation to Bayesian updating of probabilities, by also deepening some aspects of Bayes’ formula. Then, we introduce a notion of iterated c.r.q. (X|H)|K, by analyzing its relationship with X|HK. Our notion of iterated conditiona…
Intraoperative dexamethasone intravitreal implant in diabetic macular edema patients undergoing phacoemulsification: The CataDex study
2021
Purpose To assess the impact of preoperative intravitreal dexamethasone implant (DexI) on functional and anatomic outcomes in patients with diabetic macular edema (DME) who underwent phacoemulsification cataract surgery. Methods Prospective and non-comparative study conducted on consecutive DME patients undergoing cataract surgery. DexI was administered 15 days before surgery and in a pro re nata regime after surgery. Main outcome measures were mean change in central retinal thickness (CRT), central subfield thickness (CST), total macular volume (TMV), and central subfield volume (CSV) from baseline to month-12. Secondary outcome was mean change in best corrected visual acuity (BCVA). Resul…
A wavelet analysis of the ripple effect in UK regional housing markets
2021
Abstract The paper aims at gaining insights on the spatio-temporal mechanism of house price spillovers, also known as ripple effect, among 12 UK regional housing markets, over the period 1973–2018. From a policy perspective, it is essential to discriminate if the effects of a shock decay more slowly along the geographical dimension as compared to the decay along the time dimension. We enter the debate in a novel manner by using some wavelet analysis tools (wavelet coherence and phase differences amongst others) which reveal the spectral characteristics of a series and show how different periodic components of housing returns evolve over time. Results are interesting. Spillovers from London …
Dynamique induite par champ laser femtoseconde intense : alignement moléculaire en milieu gazeux dense et effet Kerr
2011
This thesis is devoted to the study of dynamics induced by intense femtoseconds lasers pulses. The first studied dynamics deals with molecular alignment of CO2-X mixtures (X=CO2, Ar, N2), in dense gases (up to 20 bar). Up to now, this regime has never been studied experimentally. In the field-free regime (after laser/matter interaction), molecular alignment exhibits two components : a permanent alignment and a transient one. The influence of collisions appears through population transfers between rotational states, which leads to a decrease of these two contributions. Permanent alignment relaxation time is only tied to inelastics collisions whereas transient alignment relaxation time is tie…
The structure of Antonovsky's Orientation to Life Questionnaire
1998
The present study investigated the structure of Antonovsky's (1987) short-form (13-item) Orientation to Life Questionnaire (OLQ). The OLQ was developed to measure sense of coherence, which consists of three interrelated components: meaningfulness, comprehensibility and manageability. Confirmatory factor analyses were carried out using data on three occupational groups (technical designers n = 989, teachers n = 1012, managers n = 1035). The factor analysis models were specified and compared in the study: (1) a first-order one-factor model; (2) a first-order correlated-three-factor model; and (3) a second-order model with three first-order factors. The results suggested that the first-order c…
On the interpretability and computational reliability of frequency-domain Granger causality
2017
This Correspondence article is a comment which directly relates to the paper “A study of problems encountered in Granger causality analysis from a neuroscience perspective” (Stokes and Purdon, 2017). We agree that interpretation issues of Granger causality (GC) in neuroscience exist, partially due to the historically unfortunate use of the name “causality”, as described in previous literature. On the other hand, we think that Stokes and Purdon use a formulation of GC which is outdated (albeit still used) and do not fully account for the potential of the different frequency-domain versions of GC; in doing so, their paper dismisses GC measures based on a suboptimal use of them. Furthermore, s…
Probabilistic entailment in the setting of coherence: The role of quasi conjunction and inclusion relation
2013
In this paper, by adopting a coherence-based probabilistic approach to default reasoning, we focus the study on the logical operation of quasi conjunction and the Goodman-Nguyen inclusion relation for conditional events. We recall that quasi conjunction is a basic notion for defining consistency of conditional knowledge bases. By deepening some results given in a previous paper we show that, given any finite family of conditional events F and any nonempty subset S of F, the family F p-entails the quasi conjunction C(S); then, given any conditional event E|H, we analyze the equivalence between p-entailment of E|H from F and p-entailment of E|H from C(S), where S is some nonempty subset of F.…