Person:
Maciá Barber, Enrique Alfonso

Profile Picture
First Name
Enrique Alfonso
Last Name
Maciá Barber
URI
https://hdl.handle.net/20.500.14352/75005
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Físicas
Department
Física de Materiales
Area
Física de la Materia Condensada
Identifiers
UCM identifierORCIDScopus Author IDWeb of Science ResearcherIDDialnet ID

Filters

2021 - 20244
Reset filters

Settings

Start date: 2020 ×

Search Results

Now showing 1 - 4 of 4
  • Thumbnail Image
    Item
    Alloy quasicrystals: perspectives and some open questions at forty years
    (Symmetry, 2023) Maciá Barber, Enrique Alfonso
    Four decades have elapsed since the first quasiperiodic crystal was discovered in the Al-Mn alloy system, and much progress has been made during this time on the science of quasicrystals (QCs). Notwithstanding this, a significant number of open questions still remain regarding both fundamental and technological aspects. For instance: What are QCs good for? How can we improve the current provisional QC definition? What is the role of the underlying quasiperiodic order and the characteristic inflation symmetry of these compounds in the emergence of their unusual physicochemical properties? What is the nature of chemical bonding in QCs formed in different sorts of materials such as alloys, oxides, or organic polymers? Herein these and other closely related issues are discussed from an interdisciplinary perspective as well as prospective future work in the field in the years to come.
  • Thumbnail Image
    Item
    Aperiodic crystals in biology
    (Journal of physics-condensed matter, 2022) Maciá Barber, Enrique Alfonso
    Biological systems display a broad palette of hierarchically ordered designs spanning over many orders of magnitude in size. Remarkably enough, periodic order, which profusely shows up in non-living ordered compounds, plays a quite subsidiary role in most biological structures, which can be appropriately described in terms of the more general aperiodic crystal notion instead. In this topical review I shall illustrate this issue by considering several representative examples, including botanical phyllotaxis, the geometry of cell patterns in tissues, the morphology of sea urchins, or the symmetry principles underlying virus architectures. In doing so, we will realize that albeit the currently adopted quasicrystal notion is not general enough to properly account for the rich structural features one usually finds in biological arrangements of matter, several mathematical tools and fundamental notions belonging to the aperiodic crystals science toolkit can provide a useful modeling framework to this end.
  • Thumbnail Image
    Item
    Synchronized oscillations in double-helix B-DNA molecules with mirror-symmetric codons
    (Symmetry, 2021) Maciá Barber, Enrique Alfonso
    A fully analytical treatment of the base-pair and codon dynamics in double-stranded DNA molecules is introduced, by means of a realistic treatment that considers different mass values for G, A, T, and C nucleotides and takes into account the intrinsic three-dimensional, helicoidal geometry of DNA in terms of a Hamitonian in cylindrical coordinates. Within the framework of the Peyrard-Dauxois-Bishop model, we consider the coupling between stretching and stacking radial oscillations as well as the twisting motion of each base pair around the helix axis. By comparing the linearized dynamical equations for the angular and radial variables corresponding to the bp local scale with those of the longer triplet codon scale, we report an underlying hierarchical symmetry. The existence of synchronized collective oscillations of the base-pairs and their related codon triplet units are disclosed from the study of their coupled dynamical equations. The possible biological role of these correlated, long-range oscillation effects in double standed DNA molecules containing mirror-symmetric codons of the form XXX, XX'X, X'XX', YXY, and XYX is discussed in terms of the dynamical equations solutions and their related dispersion relations.
  • Thumbnail Image
    Item
    Project number: PIMCD77/23-24
    Aprendizaje por proyectos en Mecánica Clásica en el grado en Física
    (2024) González Romero, Luis Manuel; González López, Artemio; Maciá Barber, Enrique Alfonso; Rubiera García, Diego; Herráez Centellas, Santiago; Zapata Ferguson, Martín; González Romero, Luis Manuel
    El objetivo principal del proyecto es el desarrollo de los materiales adecuados para la implementación de un aprendizaje parcial mediante proyectos en la asignatura de Mecánica Clásica del grado en Física/ doble grado en Física y Matemáticas, utilizando proyectos de simulación de problemas mecánicos mediante el lenguaje Python (Jupyter-notebook). El proyecto intenta así paliar la falta de motivación en el proceso de aprendizaje de las asignaturas que venimos detectando entre algunos estudiantes. Lo que pretende el proyecto es fomentar que los estudiantes se involucren de manera más activa en el proceso de aprendizaje.