Estudio y comparación del esqueleto axial de un saurópodo (Dinosauria, Sauropodomorpha) procedente de la Formación Villar del Arzobispo (Titónico-Berriasiense) de Galve, Teruel

The great vertebrate fossil record, Tithonian-Barremian in age, found in the outcrops of Galve (Teruel, Spain), has been recently increased with the discovery of sauropod remains in Cuesta Lonsal locality. The dorsal vertebral record of this sauropod is described in this paper. It was found in the Villar del Arzobispo Formation, which means the transition between the Upper Jurassic shallow marine environments to the continental environments of the Lower Cretaceous in this area of the Iberian Range. Plesiomorphic characters are present in the studied material together with derived and eight autapomorphic characters. Comparison with most representative sauropod genera of all the clades, especially Losillasaurus giganteus, from the same Formation, and a cladistic analysis, allows the conclusion that the studied material belongs to a basal neosauropod not described yet, and different than Macronaria and Diplodocidae+Dicraeosauridae. Cladistic analysis also shows a politomy in Neosauropoda node, in which the Cuesta Lonsal sauropod is included. In the future a complete study of all the material of this sauropod will provide new data to the neosauropod origin and evolutive radiation that affected them. Key words: Sauropoda, Neosauropoda, axial squeleton, Tithonian-Berriasian, Galve.El abundante registro fósil de vertebrados del intervalo Titónico-Barremiense presente en los yacimientos de Galve, ha sido engrosado en los últimos años con el hallazgo de los restos de un saurópodo en el yacimiento de Cuesta Lonsal, del cual se describe y compara en este trabajo el registro vertebral dorsal. Proviene de la Formación Villar del Arzobispo, muy rica en restos directos e indirectos de dinosaurios, y que representa la transición entre los medios marinos someros de finales del Jurásico y los medios continentales de la base del Cretácico Inferior en esta zona de la Cordillera Ibérica. Del material estudiado destaca la presencia de caracteres plesiomórficos para los saurópodos, combinados con caracteres derivados y con ocho caracteres autapomórficos. Una comparación con los géneros más representativos de los diversos clados de saurópodos, y en especial con Losillasaurus giganteus, hallado en la misma formación geológica, y un análisis cladístico, permite concluir que el registro estudiado pertenece a un neosaurópodo basal sin describir y distinto de Macronaria y de Diplodocidae + Dicraeosauridae. El análisis cladístico muestra además una amplia politomía en el nodo Neosauropoda, en el que se incluye el saurópodo de Cuesta Lonsal, cuyo estudio completo aportará en el futuro nuevos datos sobre las relaciones filogenéticas que rodean al origen de los neosaurópodos y las radiaciones evolutivas que les afectaron. Palabras clave: Sauropoda, Neosauropoda, esqueleto axial, Titónico-Berriasiense, Galvé

Observation of a Distribution of Internal Transverse Magnetic Fields in a Mn12-Based Single Molecule Magnet

A distribution of internal transverse magnetic fields has been observed in single molecule magnet (SMM) Mn12-BrAc in the pure magnetic quantum tunneling (MQT) regime. Magnetic relaxation experiments at 0.4 K are used to produce a hole in the distribution of transverse fields whose angle and depth depend on the orientation and amplitude of an applied transverse ``digging field.'' The presence of such transverse magnetic fields can explain the main features of resonant MQT in this material, including the tunneling rates, the form of the relaxation and the absence of tunneling selection rules. We propose a model in which the transverse fields originate from a distribution of tilts of the molecular magnetic easy axes.Comment: 4 page

Automated Weighing System for the Health Care of Guinea Pigs (Cavia Porcellus)

It is estimated that in Nariño (Colombia) there are 20,000 small guinea pig farms, which provide livelihoods for thousands of families and generate monthly transactions of a thousand million Colombian pesos. This sector has a trend of constant growth. However, the production of guinea pigs (Cavia porcellus) is done by hand due to the lack of technification of this sector. A problem identified in the breeding of these animals is weight loss, which can be caused by injuries in the traditional weighing process. In this process, the animal is immobilized and manually taken to the scale, which can cause injuries, stress, weight variations, reduced mobility and, in the worst cases, death. Being aware that these problems could be solved through technology, this article presents the design of an automated weighing and identification system that allows producers to carry out the weighing process without human intervention, with the purpose of safeguarding the animal’s health. The article also discusses the parameter design and information about guinea pigs, from a structural and operative point of view. Some experimental results are shown which gave rise to a patent. Finally, conclusions about the reach and use of the device are presented. Keywords: automated weighing system, RFID tagging, guinea pigs, Cavia porcellus. RESUMEN Se estima que en Nariño (Colombia) existen 20.000 criaderos pequeños de cuyes que son la base económica de miles de familias los cuales producen transacciones mensuales por mil millones de pesos colombianos. Un sector que está en constante crecimiento. Sin embargo, la producción de cuyes (Cavia porcellus) se realiza de forma artesanal debido a la falta de tecnificación. Una problemática identificada en la cría de estos animales es la pérdida de peso que puede ocasionarse por lesiones causadas en el pesaje de forma tradicional. En este proceso, el animal es inmovilizando y llevado manualmente hacia la báscula, lo que puede ocasionar lesiones, reducción de movilidad y hasta la muerte. Conscientes que dichas problemáticas podrían solucionarse a través de la tecnología, en este artículo se plantea el diseño de un sistema de pesaje e identificación automatizado que permita a los productores realizar el proceso de pesaje sin intervención humana, con el propósito de mantener el estado de salud del animal. Para esto se presenta la información recopilada y parámetros establecidos para realizar el diseño, desde un punto de vista estructural y operativo. Además, se presentan algunos resultados experimentales que dieron origen a una Patente del dispositivo, y finalmente algunas conclusiones sobre el alcance y uso del dispositivo propuesto. Palabras claves: sistema de pesaje automatizado, identificación RFID, cuyes de granja, Cavia porcellus. &nbsp

Low temperature microwave emission from molecular clusters

We investigate the experimental detection of the electromagnetic radiation generated in the fast magnetization reversal in Mn12-acetate at low temperatures. In our experiments we used large single crystals and assemblies of several small single crystals of Mn12-acetate placed inside a cylindrical stainless steel waveguide in which an InSb hot electron device was also placed to detect the radiation. All this was set inside a SQUID magnetometer that allowed to change the magnetic field and measure the magnetic moment and the temperature of the sample as the InSb detected simultaneously the radiation emitted from the molecular magnets. Our data show a sequential process in which the fast inversion of the magnetic moment first occurs, then the radiation is detected by the InSb device, and finally the temperature of the sample increases during 15 ms to subsequently recover its original value in several hundreds of milliseconds.Comment: changed conten

Relaxation and Landau-Zener experiments down to 100 mK in ferritin

Temperature-independent magnetic viscosity in ferritin has been observed from 2 K down to 100 mK, proving that quantum tunneling plays the main role in these particles at low temperature. Magnetic relaxation has also been studied using the Landau-Zener method making the system crossing zero resonant field at different rates, alpha=dH/dt, ranging from 10^{-5} to 10^{-3} T/s, and at different temperatures, from 150 mK up to the blocking temperature. We propose a new Tln(Delta H_{eff}/tau_0 alpha) scaling law for the Landau-Zener probability in a system distributed in volumes, where Delta H_{eff} is the effective width of the zero field resonance.Comment: 13 pages, 4 postscript figure

High frequency resonant experiments in Fe8_8 molecular clusters

Precise resonant experiments on Fe$_{8}$ magnetic clusters have been conducted down to 1.2 K at various tranverse magnetic fields, using a cylindrical resonator cavity with 40 different frequencies between 37 GHz and 110 GHz. All the observed resonances for both single crystal and oriented powder, have been fitted by the eigenstates of the hamiltonian ${\cal H}=-DS_z^2+ES_x^2-g\mu_B{\bf H}\cdot {\bf S}$. We have identified the resonances corresponding to the coherent quantum oscillations for different orientations of spin S = 10.Comment: to appear in Phys.Rev. B (August 2000

Magnetic qubits as hardware for quantum computers

We propose two potential realisations for quantum bits based on nanometre scale magnetic particles of large spin S and high anisotropy molecular clusters. In case (1) the bit-value basis states |0> and |1> are the ground and first excited spin states Sz = S and S-1, separated by an energy gap given by the ferromagnetic resonance (FMR) frequency. In case (2), when there is significant tunnelling through the anisotropy barrier, the qubit states correspond to the symmetric, |0>, and antisymmetric, |1>, combinations of the two-fold degenerate ground state Sz = +- S. In each case the temperature of operation must be low compared to the energy gap, \Delta, between the states |0> and |1>. The gap \Delta in case (2) can be controlled with an external magnetic field perpendicular to the easy axis of the molecular cluster. The states of different molecular clusters and magnetic particles may be entangled by connecting them by superconducting lines with Josephson switches, leading to the potential for quantum computing hardware.Comment: 17 pages, 3 figure

Definitive spectroscopic determination of the transverse interactions responsible for the magnetic quantum tunneling in Mn12-acetate

We present detailed angle-dependent single crystal electron paramagnetic resonance (EPR) data for field rotations in the hard plane of the S=10 single molecule magnet Mn12-acetate. A clear four-fold variation in the resonance positions may be attributed to an intrinsic fourth order transverse anisotropy (O44). Meanwhile, a four-fold variation of the EPR lineshapes confirms a recently proposed model wherein disorder associated with the acetic acid of crystallization induces a locally varying quadratic (rhombic) transverse anisotropy (O22). These findings explain most aspects of the magnetic quantum tunneling observed in Mn12-acetate.Comment: 7 pages, including figures, accepted for publication in Phys. Rev. Let

Procesos de transición hacia el retiro deportivo: una revisión sistemática usando la herramienta PRISMA

The phenomena of sports retreat is a topic relatively new in sports science, for this reason it is addressed currently ideas about the process towards the sports retreat as the last stage in a professional sport career and competitive longevity in long-term athletes. The objective of this systematic revision is to identify researches which involve the way how they assume the transition process towards the sports retreat and the detraining of athletes.   To carry out this work, it was necessary an examination of the data. Scopus, Ebsco and Sciencedirect along august 2022.  The analysis was done through a combination of the terms: Detraining, Retirement and Sport using the inclusion criteria. Published review articles in the last ten years, In English or Spanish that allow access to complete texts. During the search 16.642 articles were found. After applying different filters and keeping in mind the title and the research objectives, 165 of them were taken into consideration, which were examined with the application of the check list suggested by the PRISMA tool. It provided us 17 articles to be considered in this research. From these, two of them come from systematic revision, one of them with PRISMA methodology, besides four quantitative and 11 qualitative. El fenómeno del retiro deportivo es una temática relativamente nueva en el campo de las ciencias del deporte, por ello se abordan ideas actuales acerca del proceso hacia el retiro deportivo, como la última etapa dentro de sus carreras profesionales y longevidad competitiva en deportistas de alto rendimiento. El objetivo de esta revisión sistemática es identificar las investigaciones que hablan sobre la manera como se asume el proceso de transición hacia el retiro deportivo y desentrenamiento en los deportistas. Para ello se realizó una búsqueda en las bases de datos. Scopus, Ebsco y Sciencedirect durante el mes de agosto del año 2022. La consulta se realizó combinando los términos: Detraining, Retirement y Sport utilizando los criterios de inclusión. Artículos de revisión, publicados en los últimos diez años, en idiomas inglés o español y que se tuviera acceso al texto completo. Durante la búsqueda se encontraron 16.642 artículos. Luego de aplicar los diferentes filtros teniendo en cuenta el título y los objetivos de la investigación se tuvieron en cuenta 165 de ellos, a los cuales se les aplicaron de nuevo los ítems incluidos en el check list de la herramienta PRISMA teniendo como resultado 17 artículos para ser contemplados en esta investigación. De estos, dos son de revisión sistemática, 1 de ellos con metodología PRISMA, además cuatro cuantitativas y once de carácter cualitativo

Optimal Routing and Scheduling of Charge for Electric Vehicles: A Case Study

There are increasing interests in improving public transportation systems. One of the proposed strategies for this improvement is the use of Battery Electric Vehicles (BEVs). This approach leads to a new challenge as the BEVs’ routing is exposed to the traditional routing problems of conventional vehicles, as well as the particular requirements of the electrical technologies of BEVs. Examples of BEVs’ routing problems include the autonomy, battery degradation, and charge process. This work presents a differential evolution algorithm for solving an electric vehicle routing problem (EVRP). The formulation of the EVRP to be solved is based on a scheme to coordinate the BEVs’ routing and recharge scheduling, considering operation and battery degradation costs. A model based on the longitudinal dynamics equation of motion estimates the energy consumption of each BEV. A case study, consisting of an airport shuttle service scenario, is used to illustrate the proposed methodology. For this transport service, the BEV energy consumption is estimated based on experimentally measured driving patterns