Excitations and S-matrix for su(3) spin chain combining 3{3} and ${3^{*}}

The associated Hamiltonian for a su(3) spin chain combining ${3}$ and ${3^{*}}$ representations is calculated. The ansatz equations for this chain are obtained and solved in the thermodynamic limit, and the ground state and excitations are described. Thus, relations between the number of roots and the number of holes in each level have been found . The excited states are characterized by means of these quantum numbers. Finally, the exact S matrix for a state with two holes is found.Comment: 17 pages, plaintex, harvmac (to be published in J. of Phys. A

Dipolar condensates confined in a toroidal trap: ground state and vortices

We study a Bose-Einstein condensate of 52Cr atoms confined in a toroidal trap with a variable strength of s-wave contact interactions. We analyze the effects of the anisotropic nature of the dipolar interaction by considering the magnetization axis to be perpendicular to the trap symmetry axis. In the absence of a central repulsive barrier, when the trap is purely harmonic, the effect of reducing the scattering length is a tuning of the geometry of the system: from a pancake-shaped condensate when it is large, to a cigar-shaped condensate for small scattering lengths. For a condensate in a toroidal trap, the interaction in combination with the central repulsive Gaussian barrier produces an azimuthal dependence of the particle density for a fixed radial distance. We find that along the magnetization direction the density decreases as the scattering length is reduced but presents two symmetric density peaks in the perpendicular axis. For even lower values of the scattering length we observe that the system undergoes a dipolar-induced symmetry breaking phenomenon. The whole density becomes concentrated in one of the peaks, resembling an origin-displaced cigar-shaped condensate. In this context we also analyze stationary vortex states and their associated velocity field, finding that this latter also shows a strong azimuthal dependence for small scattering lengths. The expectation value of the angular momentum along the z direction provides a qualitative measure of the difference between the velocity in the different density peaks.Comment: 9 pages, 12 figure

Estudio en un caso particular de osteopatía craneomandibular en un West Highland White Terrier

Se realiza el estudio de un caso de osteopatía craneomandibular en un West Highland White Terrier cuya característica más evidente consistió en la proliferación ósea mandibular. Tras un tratamiento paliativo, el proceso sigue su curso evolutivo, ya que hasta el momento no existe terapia curativa.We realized a study of a Craneomandibular Ostheopathy in a West Highland White Terrier dog which main characteristic consisted in a proliferation process of the jaw. Following a palliative treatment, the process continues its evolutional course and sofar no curative therapy is known

Three-dimensional flow structure and bed morphology in large elongate meander loops with different outer bank roughness characteristics

© 2016. American Geophysical Union. All Rights Reserved. Few studies have examined the three-dimensional flow structure and bed morphology within elongate loops of large meandering channels. The present study focuses on the spatial patterns of three-dimensional flow structure and bed morphology within two elongate meander loops and examines how differences in outer bank roughness influence near-bank flow characteristics. Three-dimensional velocities were measured during two different events—a near-bankfull flow and an overbank event. Detailed data on channel bathymetry and bed form geometry were obtained during a near-bankfull event. Flow structure within the loops is characterized by strong topographic steering by the point bar, by the development of helical motion associated with flow curvature, and by acceleration of flow where bedrock is exposed along the outer bank. Near-bank velocities during the overbank event are less than those for the near-bankfull flow, highlighting the strong influence of the point bar on redistribution of mass and momentum of the flow at subbankfull stages. Multiple outer bank pools are evident within the elongate meander loop with low outer bank roughness, but are not present in the loop with high outer bank roughness, which may reflect the influence of abundant large woody debris on near-bank velocity characteristics. The positions of pools within both loops can be linked to spatial variations in planform curvature. The findings indicate that flow structure and bed morphology in these large elongate loops is similar to that in small elongate loops, but differs somewhat from flow structure and bed morphology reported for experimental elongate loops

Simulation of Suspensions, Torsion Bars, and Fifth Wheel for Semitrailers Using Finite Elements

The objective of this paper is the simulation of some different types of elements for semitrailers, like the suspension, both mechanical with springs and pneumatic with a spring anddiapresses; other parts like the wheels, the torsion bars, the fifth wheel and the suspension of the tractor unit have also been simulated. Then, the numerical simplified FE model of these elements that allows simulating the real behavior of the suspension to apply adequately the boundary conditions of a heavy vehicle has been obtained for a structural simulation using numerical tools with a good accuracy of the local and global behavior of the vehicle

't Hooft Expansion of 1/2 BPS Wilson Loop

We revisit the 't Hooft expansion of 1/2 BPS circular Wilson loop in N=4 SYM studied by Drukker and Gross in hep-th/0010274. We find an interesting recursion relation which relates different number of holes on the worldsheet. We also argue that we can turn on the string coupling by applying a certain integral transformation to the planar result.Comment: 21 pages; v2: minor correction

Relación entre el tipo de percha y el comportamiento de agresividad en el lagarto Norops polylepis (Squamata: Dactyloidae)

A intensidade da agressão contra intrusos por detentores de um território tem sido relacionada ao tipo de recurso disponível para um indivíduo no interior de seu território. A influência das características do poleiro sobre o comportamento de agressão de machos residentes de Norops polylepis na presença de um macho intruso foi investigada neste estudo. Em cada poleiro, foram conduzidos encontros nos quais foi registrado o comportamento agressivo dos machos residentes, além do diâmetro do poleiro e o número de poleiros das proximidades. O comportamento agressivo de machos residentes aumentou em poleiros maiores e em algum grau em áreas com maior densidade de plântulas ao redor. São discutidas explicações potenciais para o alto grau de comportamento de agressão de N. polylepis em poleiros grandes e com elevado número de plântulas ao redor.The intensity of aggression against intruders by owners of a territory has been related to the type of resources available to an individual within its territory. The influence of perch-site characteristics on aggressive behavior of resident male Norops polylepis in presence of an intruder male was investigated in this study. At each perch site, pairwise encounters were conducted in which the aggressive behavior of resident males was recorded, along with the diameter of the perch and the number of nearby perches. Aggressive behavior of resident males increased on larger perches and to some extent in areas having greater density of nearby saplings. Potential explanations for the high aggressive behavior of N. polylepis on broad perches with high number of neighboring saplings are explored.La intensidad de agresión por individuos que son dueños de un territorio hacia los intrusos se ha relacionado con el tipo de recurso disponible en sus territorios. La influencia de las características del sitio de percha con el comportamiento de agresividad de los machos residentes de Norops polylepis en presencia de un macho intruso se investigó en este estudio. En cada sitio de percha se registró el comportamiento agresivo de los residentes, junto con los diámetros de percha y árboles jóvenes alrededor. Se encontró evidencia de que la agresión de los residentes incrementó en perchas con mayor diámetro y áreas con mayor densidad de árboles jóvenes. Explicaciones potenciales por el alto nivel de agresividad de N. polylepis en perchas anchas y con mayor número de árboles jóvenes alrededor fueron exploradas

A forced migration due to covid19 from a face-to-face university education service to a total online learning management system support: UDELAS-Panamá study case

The Covid-19 pandemic forced the Specialized University of the Americas (UDELAS, Panamá) to transform their educational service from almost 100% face-to-face to 100% virtual in approximately three weeks. This change involved creating 2,500 virtual courses and integrating nearly 9,000 students and 1,200 teachers into them. The research question to answer: Is it possible to schedule a proposed Learning Management System (LMS) tested on the go, in two effective months to institutionally can adopting latter an effective teaching-learning process total online? For testing which LMS online service to choose, two types of well-known LMS were selected: Moodle, which is an open source LMS centralized with a complete control over its components and services, and Google's Classroom, as a decentralized LMS running essentially in the cloud, which is conducive to a user/personal management, avoiding in the short term, to attend many hardware and software technical issues. Under a methodological process alike Agile style, the expansion of technological capabilities in the Moodle implementation took three weeks. In parallel, to implement Classroom, 12,000 institutional Google accounts were generated using the G Suite for Education license (in agreement with Google Mexico chapter). An institutional email account was established as the digital identity of professors and students, throughout they can access both LMSs. In addition, a group of the professors chose to combine applications instead of using Moodle or Classroom alone, it was called the combined option