Search results for "points"
showing 10 items of 415 documents
Forecasts on the development of hydrogen refuelling infrastructures in Portugal
2021
In Portugal, the transition to new forms of mobility has begun in recent years, but there are still obstacles to overcome. Currently, hybrid vehicles (PHEVs) are the most widespread and accepted by the community and that is probably due to range anxiety, having in fact the possibility of double charging (both through the thermal engine and the electric battery). Furthermore, it must be considered that in addition to electric vehicles, another valid alternative to mobility in the near future is the hydrogen vehicles one. These appear to be even more sustainable from the point of view of air emissions, but on the other hand the costs for the production of hydrogen are still too high. Then, th…
On a step method and a propagation of discontinuity
2019
In this paper we analyze how to compute discontinuous solutions for functional differential equations, looking at an approach which allows to study simultaneously continuous and discontinuous solutions. We focus our attention on the integral representation of solutions and we justify the applicability of such an approach. In particular, we improve the step method in such a way to solve a problem of vanishing discontinuity points. Our solutions are considered as regulated functions.
The budding yeast Start repressor Whi7 differs in regulation from Whi5, emerging as a major cell cycle brake in response to stress
2020
ABSTRACT Start is the main decision point in the eukaryotic cell cycle at which cells commit to a new round of cell division. It involves the irreversible activation of a transcriptional programme through the inactivation of Start transcriptional repressors: the retinoblastoma family in mammals, or Whi5 and its recently identified paralogue Whi7 (also known as Srl3) in budding yeast. Here, we provide a comprehensive comparison of Whi5 and Whi7 that reveals significant qualitative differences. Indeed, the expression, subcellular localization and functionality of Whi7 and Whi5 are differentially regulated. Importantly, Whi7 shows specific properties in its association with promoters not share…
Primitives detection by a discrete and non linear approach : application to the detection and caracterization of interest points for 3D meshes
2010
This manuscript is dedicated to the detection and caracterization of interest points for 3D meshes. First of all, we show the limitations of the curvature measure on sharp edges, the measure usually used for the analysis of meshes. Then, we present a generalization of the SUSAN operator for meshes, named SUSAN-3D. The saliency measure proposed quantify the local variation of the surface and classify directly the analysed vertices in five classes: salient, crest, flat, valley and cavity. The meshes under consideration are manifolds and can be closed or non-closed, regulars or irregulars, dense or not and noised or not. The accuracy of the SUSAN-3D operator is compared to two curvature operat…
Two Times Four Integrative Levels of Analysis: A Framework
2001
Walsham (2000) urged Information Systems researchers to truly cover all levels of analysis from the individual to the societal in their research agenda. In this paper, we accept his challenge by proposing a research framework offour integrative levels of analysis: individual, group/activity, organizational, and societal. Each level is divided into two viewpoints: intra (single case) and inter (multiple cases, relational, comparative). In addition, the temporal/historical dimension should be applied on all levels and viewpoints. We argue that although all of the levels and viewpoints of the “2 × 4 + history” framework cannot be thoroughly covered in any single study, researchers should alway…
Periodic solutions for a class of second-order Hamiltonian systems
2005
Multiplicity results for an eigenvalue second-order Hamiltonian system are investigated. Using suitable critical points arguments, the existence of an exactly determined open interval of positive eigenvalues for which the system admits at least three distinct periodic solutions is established. Moreover, when the energy functional related to the Hamiltonian system is not coercive, an existence result of two distinct periodic solutions is given.© 2005 Texas State University - San Marcos.
A fast and efficient picking algorithm for earthquake early warning application based on the variance piecewise constant models
2020
An earthquake warning system, or earthquake early warning system, is a system of accelerometers, seismometers, communication, computers, and alarms that is devised for notifying adjoining regions of a substantial earthquake while it is in progress. This is not the same as earthquake prediction, which is currently incapable of producing decisive event warnings. The implementation of efficient and computationally simple picking algorithm is necessary for this purpose, as well as automatic picking of seismic phases for seismic surveillance and routine earthquake location for fast hypocenter determination. In this paper a method for picking based on the detection of signals changes in variance …
Frame analysis of psychotherapists’ perspectives on the development of psychological disorders
2021
AbstractThe development of psychological disorders has been explained by several psychological theories and remains under debate. Psychotherapists, however, have insights into the emergence and development of psychological disorders that stem from both theory and practice. The constantly evolving field of psychotherapy prompts reconsideration, specifically when psychotherapists’ views on the development of disorders impacts their treatment approach. In addition, theoretical orientation and years of clinical experience, while known to influence psychotherapists’ viewpoints also merit further study. Applying Erving Goffman’s frame analysis, semi structured interviews with psychotherapists wer…
Drawings, Gestures and Discourses: A Case Study with Kindergarten Students Discovering Lego Bricks
2020
This paper presents a study aimed at investigating the didactic potentiality of the use of an artefact, useful to construct mathematical meanings concerning the coordination of different points of view, in the observation of a real object/toy. In our view, the process of meaning construction can be fostered by the use of adequate artefacts, but it requires a teaching/learning model, which explicitly takes care of the evolution of meanings, from those personal, emerging through the activities, to the mathematical ones, aims of the teaching intervention. The main hypothesis of this study is that the alternation between different semiotic systems, graphical system, verbal system and system of …
DNA damage causes TP53-dependent coupling of self-renewal and senescence pathways in embryonal carcinoma cells.
2013
Recent studies have highlighted an apparently paradoxical link between self-renewal and senescence triggered by DNA damage in certain cell types. In addition, the finding that TP53 can suppress senescence has caused a re-evaluation of its functional role in regulating these outcomes. To investigate these phenomena and their relationship to pluripotency and senescence, we examined the response of the TP53-competent embryonal carcinoma (EC) cell line PA-1 to etoposide-induced DNA damage. Nuclear POU5F1/OCT4A and P21CIP1 were upregulated in the same cells following etoposide-induced G 2M arrest. However, while accumulating in the karyosol, the amount of OCT4A was reduced in the chromatin fract…