Palindromic Vectors, Symmetropy and Symmentropy as Symmetry Descriptors of Binary Data

Today, the palindromic analysis of biological sequences, based exclusively on the study of “mirror” symmetry properties, is almost unavoidable. However, other types of symmetry, such as those present in friezes, could allow us to analyze binary sequences from another point of view. New tools, such as symmetropy and symmentropy, based on new types of palindromes allow us to discriminate binarized 1/f noise sequences better than Lempel–Ziv complexity. These new palindromes with new types of symmetry also allow for better discrimination of binarized DNA sequences. A relative error of 6% of symmetropy is obtained from the HUMHBB and YEAST1 DNA sequences. A factor of 4 between the slopes obtained from the linear fits of the local symmentropies for the two DNA sequences shows the discriminative capacity of the local symmentropy. Moreover, it is highlighted that a certain number of these new palindromes of sizes greater than 30 bits are more discriminating than those of smaller sizes assimilated to those from an independent and identically distributed random variable.

Dipole Moment and Pressure Dependent Interlayer Excitons in MoSSe/WSSe Heterostructures

The broken mirror symmetry of the two-dimensional (2D) Janus material brings novel quantum properties and various application prospects. Particularly, when stacking into heterostructure, its intrinsic dipole moments and large band...

Interocular Symmetry Analysis of Corneal Elevation Using the Fellow Eye as the Reference Surface and Machine Learning

Unilateral corneal indices and topography maps are routinely used in practice, however, although there is consensus that fellow-eye asymmetry can be clinically significant, symmetry studies are limited to local curvature and single-point thickness or elevation measures. To improve our current practices, there is a need to devise algorithms for generating symmetry colormaps, study and categorize their patterns, and develop reference ranges for new global discriminative indices for identifying abnormal corneas. In this work, we test the feasibility of using the fellow eye as the reference surface for studying elevation symmetry throughout the entire corneal surface using 9230 raw Pentacam files from a population-based cohort of 4613 middle-aged adults. The 140 × 140 matrix of anterior elevation data in these files were handled with Python to subtract matrices, create color-coded maps, and engineer features for machine learning. The most common pattern was a monochrome circle (“flat”) denoting excellent mirror symmetry. Other discernible patterns were named “tilt”, “cone”, and “four-leaf”. Clustering was done with different combinations of features and various algorithms using Waikato Environment for Knowledge Analysis (WEKA). Our proposed approach can identify cases that may appear normal in each eye individually but need further testing. This work will be enhanced by including data of posterior elevation, thickness, and common diagnostic indices.

СИМЕТРІЯ В ДИЗАЙНІ ВІЗУАЛЬНИХ КОМУНІКАЦІЙ: СПОСОБИ ПОБУДОВИ ДИНАМІЧНОГО ХУДОЖНЬОГО ОБРАЗУ

The purpose of the study is to reveal methods of image creation in dynamic visual communications based on symmetry. Methodology. Research methodology is interdisciplinary. It is based on systems and synergistical approaches. They consider dynamic visual communications as an integral field of interaction between human and environment. We systematized design methods of the image creation of a visual message by using the system and functional, structural and dynamic, composition, artistic and image design-analyses according to the principles of symmetry. Results. We represent symmetry as a method of dynamic visual communications form and image creation. Symmetrical relations are formed at the object structure level (mirror symmetry and central symmetry), the process level (translational symmetry, multilevel central symmetry and radial symmetry) and environment level (scale invariance and recursion). Integrative basis strengthening allows forming the structure of the image content providing fusion with an environment. Rethinking of the design methods on the based on the principles of symmetry increases the efficiency of perception and visual communications dynamic in the context of changeable external conditions. Scientific novelty. In the research we rethought the role of symmetry in dynamic visual communications design based on the systems approach for the first time. It is well-proven that the symmetric transformations support increasing of aesthetic, functional and communicative qualities of dynamic visual information. Practical significance. Research materials can serve as basis for harmonization and optimization of the form and content of different visual communications types. Their image structurization according to the principles of symmetry provides new development strategies of the integrated visual communications. It is important to increase perception efficiency in the conditions of continuously growing information volumes. Researched design methods of visual communications symmetric structures can be used by specialists in order to arrange the modern space. We also use them as the basis for designers’ system thinking forming as an educational technology.

Euclidean D-branes in type IIB string theory on Calabi-Yau threefolds

We compute the contribution of Euclidean D-branes in type IIB string theory on Calabi-Yau threefolds to the metric on the hypermultiplet moduli space in the large volume, weak coupling limit. Our results are in perfect agreement with the predictions based on S-duality, mirror symmetry and supersymmetry.

Connecting 5d Higgs branches via Fayet-Iliopoulos deformations

We describe how the geometry of the Higgs branch of 5d superconformal field theories is transformed under movement along the extended Coulomb branch. Working directly with the (unitary) magnetic quiver, we demonstrate a correspondence between Fayet-Iliopoulos deformations in 3d and 5d mass deformations. When the Higgs branch has multiple cones, characterised by a collection of magnetic quivers, the mirror map is not globally well-defined, however we are able to utilize the correspondence to establish a local version of mirror symmetry. We give several detailed examples of deformations, including decouplings and weak-coupling limits, in (Dn, Dn) conformal matter theories, TN theory and its parent PN, for which we find new Lagrangian descriptions given by quiver gauge theories with fundamental and anti-symmetric matter.

Degenerate topological line surface phonons in quasi-1D double helix crystal SnIP

Degenerate points/lines in the band structures of crystals have become a staple of the growing number of topological materials. The bulk-boundary correspondence provides a relation between bulk topology and surface states. While line degeneracies of bulk excitations have been extensively characterised, line degeneracies of surface states are not well understood. We show that SnIP, a quasi-one-dimensional van der Waals material with a double helix crystal structure, exhibits topological nodal rings/lines in both the bulk phonon modes and their corresponding surface states. Using a combination of first-principles calculations, symmetry-based indicator theories and Zak phase analysis, we find that two neighbouring bulk nodal rings form doubly degenerate lines in their drumhead-like surface states, which are protected by the combination of time-reversal symmetry $${{{\mathcal{T}}}}$$ T and glide mirror symmetry $${\bar{M}}_{y}$$ M ¯ y . Our results indicate that surface degeneracies can be generically protected by symmetries such as $${{{\mathcal{T}}}}{\bar{M}}_{y}$$ T M ¯ y , and phonons provide an ideal platform to explore such degeneracies.

Fluorescence Spectroscopy of Enantiomeric Amide Compounds Enforced by Chiral Light

Chirality, the absence of mirror symmetry, governs behavior in most biologically important molecules, thus making the chiral recognition of great importance in the pharmaceutical and agrochemical industries, as well as medicine. Chiral molecules can be characterized by means of optical experiments based on chiro-optical excitation of molecules. Specifically, chiral absorptive materials differently absorb left- and right-circular polarized light, i.e., they possess circular dichroism (CD). Unfortunately, the natural CD of most molecules is very low and lies in the ultraviolet range. Fluorescence-detected CD is a fast and sensitive tool for investigation of chiral molecules which emit light; ultralow CD in absorption can be detected as the difference in emission. In this work, we perform fluorescence-detected CD on novel chiral amide compounds, designed specifically for visible green emission; we synthesize two enantiomeric fluorescent compounds using low-cost starting compounds and easy purification. We investigate different solutions of the enantiomers at different concentrations, and we show that the fluorescence of the intrinsically chiral compounds depends on the polarization state of the penetrating light, which is absorbed at 400 nm and emits across the green wavelength range. We believe that these compounds can be coupled with plasmonic nanostructures, which further shows promise in applications regarding chiral sensing or chiral emission.