Search results for " box"

Oscillatory integrals and fractal dimension

2021

Theory of singularities has been closely related with the study of oscillatory integrals. More precisely, the study of critical points is closely related to the study of asymptotic of oscillatory integrals. In our work we investigate the fractal properties of a geometrical representation of oscillatory integrals. We are motivated by a geometrical representation of Fresnel integrals by a spiral called the clothoid, and the idea to produce a classification of singularities using fractal dimension. Fresnel integrals are a well known class of oscillatory integrals. We consider oscillatory integral $$ I(\tau)=\int_{; ; \mathbb{; ; R}; ; ^n}; ; e^{; ; i\tau f(x)}; ; \phi(x) dx, $$ for large value…

Carbocysteine counteracts the effects of cigarette smoke on cell growth and on the SIRT1/FoxO3 axis in bronchial epithelial cells

2016

Abstract Background Cigarette smoke may accelerate cellular senescence by increasing oxidative stress. Altered proliferation and altered expression of anti-aging factors, including SIRT1 and FoxO3, characterise cellular senescence. The effects of carbocysteine on the SIRT1/FoxO3 axis and on downstream molecular mechanisms in human bronchial epithelial cells exposed to cigarette smoke are largely unknown. Aims Aim of this study was to explore whether carbocysteine modulated SIRT1/FoxO3 axis, and downstream molecular mechanisms associated to cellular senescence, in a bronchial epithelial cell line (16-HBE) exposed to cigarette smoke. Methods 16HBE cells were stimulated with/without cigarette …

Do Pied Flycatcher Females Defend an Extra Nest Hole Against Conspecific Females?

1999

AbstractIn birds, females are often aggressive against conspecific females during the breeding. There are many explanations for this intrasexual aggression by females: e.g., nest site or food resource defence, prevention of intraspecific brood parasitism or infanticide, and monopolization of paternal care. A pair might also benefit by defending an alternative nest site in addition to the current nest site. Here, I study by experimentation whether pied flycatcher (Ficedula hypoleuca) females defend an extra nest box as an alternative nesting site. Further, I examine whether females behave differently when their mate is present vs not present. I measured the reactions by resident females to a…

Regulation of Protein-DNA Interactions at the Interferon-gamma Gene Promoter by Corticosteroids

1998

Explaining Individual and Collective Programming Students’ Behavior by Interpreting a Black-Box Predictive Model

2021

Predicting student performance as early as possible and analysing to which extent initial student behaviour could lead to failure or success is critical in introductory programming (CS1) courses, for allowing prompt intervention in a move towards alleviating their high failure rate. However, in CS1 performance prediction, there is a serious lack of studies that interpret the predictive model’s decisions. In this sense, we designed a long-term study using very fine-grained log-data of 2056 students, collected from the first two weeks of CS1 courses. We extract features that measure how students deal with deadlines, how they fix errors, how much time they spend programming, and so forth. Subs…

Resveratrol-mediated apoptosis of hodgkin lymphoma cells involves SIRT1 inhibition and FOXO3a hyperacetylation

2012

Resveratrol (RSV), a plant-derived stilbene, induces cell death in Hodgkin lymphoma (HL)-derived L-428 cells in a dose-dependent manner (IC50 = 27 μM, trypan blue exclusion assay). At a lower range (25 μM), RSV treatment for 48 hr causes arrest in the S-phase of the cell cycle, while at a higher concentration range (50 μM), apoptosis can be detected, with activation of caspase-3. The histone/protein deacetylase SIRT1 has been described as a putative target of RSV action in other model systems, even though its role in cancer cells is still controversial. Here we show that RSV, at both concentration ranges, leads to a marked increase in p53, while a decrease of SIRT1 expression level, as well…

Ectoparasites, nest site choice and breeding success in the pied flycatcher

1994

It has recently been suggested that nest box studies might bias the measurement of behavioural and life-history traits, because the removal of old nests may reduce the load of ectoparasites. This experimental artefact may have notable effects on nest site choice and breeding success in cavity-breeding birds. We tested (i) if pied flycatchers Ficedula hypoleuca prefer clean nest boxes and (ii) if old nest material affects the number of parasites and the breeding success of pied flycatchers. In the first experiment we offered birds one cleaned nest box and one nest box with old nest material from the previous year. The two nest boxes were placed in very similar sites near each other. In this …

Computing the Cell

2015

Here I call for the need to revisit cell theory. The idea that the cell is the basic unit of life is well-known and foundational to Biology, but it has not received sufficient attention. We have increasingly detailed knowledge of the intracellular world and all its components, but these are often considered independently. On the other hand, there is excessive theorising about the cell on the basis of its being a black box. The time is ripe to formulate an integrative cell theory .

Combining conjunctive rule extraction with diffusion maps for network intrusion detection

2013

Network security and intrusion detection are important in the modern world where communication happens via information networks. Traditional signature-based intrusion detection methods cannot find previously unknown attacks. On the other hand, algorithms used for anomaly detection often have black box qualities that are difficult to understand for people who are not algorithm experts. Rule extraction methods create interpretable rule sets that act as classifiers. They have mostly been combined with already labeled data sets. This paper aims to combine unsupervised anomaly detection with rule extraction techniques to create an online anomaly detection framework. Unsupervised anomaly detectio…

Optimized spatio-temporal descriptors for real-time fall detection: comparison of support vector machine and Adaboost-based classification

2013

We propose a supervised approach to detect falls in a home environment using an optimized descriptor adapted to real-time tasks. We introduce a realistic dataset of 222 videos, a new metric allowing evaluation of fall detection performance in a video stream, and an automatically optimized set of spatio-temporal descriptors which fed a supervised classifier. We build the initial spatio-temporal descriptor named STHF using several combinations of transformations of geometrical features (height and width of human body bounding box, the user’s trajectory with her/his orientation, projection histograms, and moments of orders 0, 1, and 2). We study the combinations of usual transformations of the…