scholarly journals Primality, Fractality, and Image Analysis

Entropy ◽  
2019 ◽  
Vol 21 (3) ◽  
pp. 304 ◽  
Author(s):  
Emanuel Guariglia
Keyword(s):  
Color Image ◽  
Prime Numbers ◽  
Cantor Set ◽  
Integer Sequences ◽  
Binary Images ◽  
Fractal Sets ◽  
Chaotic Dynamical Systems ◽  
Numerical Studies ◽  
Relevant Role

This paper deals with the hidden structure of prime numbers. Previous numerical studies have already indicated a fractal-like behavior of prime-indexed primes. The construction of binary images enables us to generalize this result. In fact, two-integer sequences can easily be converted into a two-color image. In particular, the resulting method shows that both the coprimality condition and Ramanujan primes resemble the Minkowski island and Cantor set, respectively. Furthermore, the comparison between prime-indexed primes and Ramanujan primes is introduced and discussed. Thus the Cantor set covers a relevant role in the fractal-like description of prime numbers. The results confirm the feasibility of the method based on binary images. The link between fractal sets and chaotic dynamical systems may allow the characterization of the Hénon map only in terms of prime numbers.

scholarly journals Presenting a Semi-Automatic, Statistically-Based Approach to Assess the Sharpness Level of Optical Images from Natural Targets via the Edge Method. Case Study: The Landsat 8 OLI–L1T Data

2021 ◽  
Vol 13 (8) ◽  
pp. 1593
Author(s):  
Luca Cenci ◽  
Valerio Pampanoni ◽  
Giovanni Laneve ◽  
Carla Santella ◽  
Valentina Boccia
Keyword(s):  
Landsat 8 ◽  
Image Sharpness ◽  
Optical Images ◽  
Data Quality Assessment ◽  
Relevant Role ◽  
Edge Method ◽  
Selection Of ◽  
Statistical Criteria

Developing reliable methodologies of data quality assessment is of paramount importance for maximizing the exploitation of Earth observation (EO) products. Among the different factors influencing EO optical image quality, sharpness has a relevant role. When implementing on-orbit approaches of sharpness assessment, such as the edge method, a crucial step that strongly affects the final results is the selection of suitable edges to use for the analysis. Within this context, this paper aims at proposing a semi-automatic, statistically-based edge method (SaSbEM) that exploits edges extracted from natural targets easily and largely available on Earth: agricultural fields. For each image that is analyzed, SaSbEM detects numerous suitable edges (e.g., dozens-hundreds) characterized by specific geometrical and statistical criteria. This guarantees the repeatability and reliability of the analysis. Then, it implements a standard edge method to assess the sharpness level of each edge. Finally, it performs a statistical analysis of the results to have a robust characterization of the image sharpness level and its uncertainty. The method was validated by using Landsat 8 L1T products. Results proved that: SaSbEM is capable of performing a reliable and repeatable sharpness assessment; Landsat 8 L1T data are characterized by very good sharpness performance.

scholarly journals Lights and Shadows in the Genetics of Syndromic and Non-Syndromic Hearing Loss in the Italian Population

Genes ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1237
Author(s):  
Anna Morgan ◽  
Stefania Lenarduzzi ◽  
Beatrice Spedicati ◽  
Elisabetta Cattaruzzi ◽  
Flora Maria Murru ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Disease Genes ◽  
Italian Population ◽  
Essential Information ◽  
Whole Exome ◽  
Relevant Role ◽  
Multiplex Ligation Probe Amplification ◽  
Syndromic Hearing Loss

Hearing loss (HL), both syndromic (SHL) and non-syndromic (NSHL), is the most common sensory disorder, affecting ~460 million people worldwide. More than 50% of the congenital/childhood cases are attributable to genetic causes, highlighting the importance of genetic testing in this class of disorders. Here we applied a multi-step strategy for the molecular diagnosis of HL in 125 patients, which included: (1) an accurate clinical evaluation, (2) the analysis of GJB2, GJB6, and MT-RNR1 genes, (3) the evaluation STRC-CATSPER2 and OTOA deletions via Multiplex Ligation Probe Amplification (MLPA), (4) Whole Exome Sequencing (WES) in patients negative to steps 2 and 3. Our approach led to the characterization of 50% of the NSHL cases, confirming both the relevant role of the GJB2 (20% of cases) and STRC deletions (6% of cases), and the high genetic heterogeneity of NSHL. Moreover, due to the genetic findings, 4% of apparent NSHL patients have been re-diagnosed as SHL. Finally, WES characterized 86% of SHL patients, supporting the role of already know disease-genes. Overall, our approach proved to be efficient in identifying the molecular cause of HL, providing essential information for the patients’ future management.

Une Caractérisation des Polynômes Prenant des Valeurs Entières Sur Tous les Nombres Premiers

1996 ◽  
Vol 39 (4) ◽  
pp. 402-407 ◽  
Author(s):  
Jean-Luc Chabert
Keyword(s):  
Prime Numbers

AbstractWe give a characterization of polynomials with rational coefficients which take integral values on the prime numbers: to test a polynomial of degree n, it is enough to consider its values on the integers from 1 to 2n —1.

Experimental Characterization of FSW T-Joints of Light Alloys

2007 ◽  
Vol 344 ◽  
pp. 751-758 ◽  
Author(s):  
Livan Fratini ◽  
Fabrizio Micari ◽  
Antonio Squillace ◽  
G. Giorleo
Keyword(s):  
Rolling Direction ◽  
Mechanical Analysis ◽  
T Joints ◽  
Light Alloys ◽  
Friction Stir ◽  
Relevant Role ◽  
Numerous Data ◽  
Few Data ◽  
Welding Direction

Welding is playing a growing role in transport industry due to relevant advantages it allows. Friction Stir Welding is considered one of the most promising joining technologies, especially when it is applied to light alloys. Focusing attention on FSW of T-joints, several parameters have to be considered, and due to thermo-mechanical features of process, T joints need a dedicated approach. A set of previously developed experiments has shown that the tilt angle plays a relevant role in the joint strength. Furthermore it should be observed that T-joints are very often utilized in aerospace industries since the produced structures are composed of joined skins and stingers. Numerous data are reported in literature about FSW of butt joints, very few data, to authors’ knowledge, exists on T joints. In this paper a micro structural and mechanical analysis has been developed on FSW T-joints of AA 6082 T6 rolled plates, realized setting welding direction both parallel and perpendicular to rolling direction. The obtained results can be considered as a further acquired knowledge in the comprehension and the design of FSW processes.

Electron Paramagnetic Resonance as a Probe for Metal Ions and Radicals in Paper

2015 ◽  
Vol 36 (4) ◽  
Author(s):  
Alfonso Zoleo ◽  
Laura Speri ◽  
Maddalena Bronzato
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Metal Ions ◽  
Chemical Species ◽  
Paramagnetic Species ◽  
Paramagnetic Resonance ◽  
Relevant Role ◽  
Historic Paper ◽  
Electron Paramagnetic ◽  
Identification And Characterization

AbstractElectron Paramagnetic Resonance (EPR) is a technique devoted to the identification and characterization of paramagnetic species, i.e. chemical species with unpaired electrons. Very common paramagnetic species which can be detected through EPR in historic paper are Fe(III), Mn(II), Cu(II) ions and radicals, where Fe(III), Cu(II) and radicals play a relevant role in paper degradation. Specifically, Fe(III) is almost ubiquitous in historic paper. Here we propose an overview of the EPR signals in historic and artificially aged paper, and in particular, we would like to show how a deep analysis of EPR signals from paper could provide useful information about the paper’s origin and unique indications of the degradation and oxidation level of the paper.

scholarly journals Functional Characterization of Cholinergic Receptors in Melanoma Cells

Cancers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3141
Author(s):  
Anna Maria Lucianò ◽  
Ada Maria Tata
Keyword(s):  
Nervous System ◽  
Acetylcholine Receptors ◽  
Epithelial Mesenchymal Transition ◽  
Functional Characterization ◽  
Physiological Role ◽  
Melanoma Cells ◽  
Cholinergic Receptors ◽  
Mesenchymal Transition ◽  
Relevant Role

In the last two decades, the scientific community has come to terms with the importance of non-neural acetylcholine in light of its multiple biological and pathological functions within and outside the nervous system. Apart from its well-known physiological role both in the central and peripheral nervous systems, in the autonomic nervous system, and in the neuromuscular junction, the expression of the acetylcholine receptors has been detected in different peripheral organs. This evidence has contributed to highlight new roles for acetylcholine in various biological processes, (e.g., cell viability, proliferation, differentiation, migration, secretion). In addition, growing evidence in recent years has also demonstrated new roles for acetylcholine and its receptors in cancer, where they are involved in the modulation of cell proliferation, apoptosis, angiogenesis, and epithelial mesenchymal transition. In this review, we describe the functional characterization of acetylcholine receptors in different tumor types, placing attention on melanoma. The latest set of data accessible through literature, albeit limited, highlights how cholinergic receptors both of muscarinic and nicotinic type can play a relevant role in the migratory processes of melanoma cells, suggesting their possible involvement in invasion and metastasis.

Correcting Measurement Nonlinearity in Dynamic Nanoindentation

2006 ◽  
Author(s):  
Brian P. Mann ◽  
Jian Liu ◽  
Siddharth Hazra
Keyword(s):  
Contact Force ◽  
Electrostatic Force ◽  
Primary Resonance ◽  
Capacitive Transducer ◽  
Material Surface ◽  
Secondary Resonances ◽  
Numerical Studies ◽  
Different Sources ◽  
Dynamic Nanoindentation

This paper investigates methods of improving measurement interpretations in dynamic nanoindentation. In particular, a shift in the system's primary resonance is observed experimentally and investigated through modeling and numerical studies. The result of these investigations is that different sources of nonlinearity, namely, nonlinearities from the tip-sample contact force and the indenter's capacitive transducer, compete to alter the system's primary and secondary resonances. Furthermore, this study implies that the accurate characterization of a material surface requires the implementation of higher fidelity models that include nonlinear expressions, as opposed to linearized versions, for the tip-sample contact force and transducer electrostatic force.

scholarly journals Scattering from generalized Cantor fractals

2010 ◽  
Vol 43 (4) ◽  
pp. 790-797 ◽  
Author(s):  
A. Yu. Cherny ◽  
E. M. Anitas ◽  
A. I. Kuklin ◽  
M. Balasoiu ◽  
V. A. Osipov
Keyword(s):  
Fractal Dimension ◽  
Small Angle ◽  
Cantor Set ◽  
Small Angle Scattering ◽  
Three Dimensions ◽  
Radius Of Gyration ◽  
Large Wave ◽  
Fractal Sets ◽  
Power Law Decay ◽  
Angle Scattering

A fractal with a variable fractal dimension, which is a generalization of the well known triadic Cantor set, is considered. In contrast with the usual Cantor set, the fractal dimension is controlled using a scaling factor, and can vary from zero to one in one dimension and from zero to three in three dimensions. The intensity profile of small-angle scattering from the generalized Cantor fractal in three dimensions is calculated. The system is generated by a set of iterative rules, each iteration corresponding to a certain fractal generation. Small-angle scattering is considered from monodispersive sets, which are randomly oriented and placed. The scattering intensities represent minima and maxima superimposed on a power law decay, with the exponent equal to the fractal dimension of the scatterer, but the minima and maxima are damped with increasing polydispersity of the fractal sets. It is shown that, for a finite generation of the fractal, the exponent changes at sufficiently large wave vectors from the fractal dimension to four, the value given by the usual Porod law. It is shown that the number of particles of which the fractal is composed can be estimated from the value of the boundary between the fractal and Porod regions. The radius of gyration of the fractal is calculated analytically.

Sign in / Sign up

Export Citation Format

Share Document