New spin Calogero-Sutherland models related to B_N-type Dunkl operators

We construct several new families of exactly and quasi-exactly solvable BC_N-type Calogero-Sutherland models with internal degrees of freedom. Our approach is based on the introduction of two new families of Dunkl operators of B_N type which, together with the original B_N-type Dunkl operators, are shown to preserve certain polynomial subspaces of finite dimension. We prove that a wide class of quadratic combinations involving these three sets of Dunkl operators always yields a spin Calogero-Sutherland model, which is (quasi-)exactly solvable by construction. We show that all the spin Calogero-Sutherland models obtainable within this framework can be expressed in a unified way in terms of a Weierstrass P function with suitable half-periods. This provides a natural spin counterpart of the well-known general formula for a scalar completely integrable potential of BC_N type due to Olshanetsky and Perelomov. As an illustration of our method, we exactly compute several energy levels and their corresponding wavefunctions of an elliptic quasi-exactly solvable potential for two and three particles of spin 1/2.Comment: 18 pages, typeset in LaTeX 2e using revtex 4.0b5 and the amslatex package Minor changes in content, one reference adde

Seguridad emocional y relaciones familiares de estudiantes universitarios españoles

[Abstract] This study is grounded on Systems Theory and Emotional Security Theory, and aims at extending past work by examining relations among children’s emotional security in the family system and the quality of family relationships among college students, a population scarcely addressed by the Emotional Security Theory. Participants were 236 female and male students attending a public Spanish University (meanage = 20.13 years old). We used the Security in the Family System Scale (SIFS), the Family Stress Scale, the Family Satisfaction Scale, the Bidirectional Parent-Adolescent Relationships Scale (BiPAR), and measures of destructive and constructive interparental conflict. The variables “living with family” and “parental divorce” were also studied. Results showed that parental divorce related to higher family stress, less interparental conflict resolution and worse bidirectional relationships with fathers. There were not significant differences in any of the variables under analyses between students who lived with their families while at college compared to those who did not live with their families. Emotional security in the family explained 52% of the variance of family satisfaction. This study has theoretical implications as it applies Emotional Security Theory to study young adults from divorced and intact families and who either live or not with their families while attending college. Our results agree and support this Theory. It also has practical implications for mental health and counselling services pointing to potential risk and protective family variables in college students.[Resumen] Este trabajo tiene como base teórica la Teoría Sistémica y la Teoría de la Seguridad Emocional, y su objetivo es ampliar estudios previos al analizar las relaciones entre la seguridad emocional en el sistema familiar y la calidad de las relaciones familiares de los estudiantes universitarios, una población poco estudiada desde la Teoría de la Seguridad Emocional. Participaron 236 hombres y mujeres que estudiaban en una universidad pública española (mediaedad = 20.13 años). Se usó la Escala de Seguridad en el Sistema Familiar (SIFS), La Escala de Estrés Familiar, La Escala de Satisfacción Familiar y la Escala de Relaciones Bidireccionales Padres-Hijos (BiPAR), así como medidas de conflicto interparental constructivo y destructivo. También se consideraron las variables “vivir con la familia” y “divorcio de los padres”. Los resultados indicaron que el divorcio de los progenitores se relacionó con mayor estrés familiar, menos resolución constructiva de los conflictos y peores relaciones bidireccionales con los padres. No se hallaron diferencias significativas entre los estudiantes que vivían con sus familias y los que no. La seguridad emocional explicaba el 52% de la varianza de la satisfacción familiar. Este trabajo tiene implicaciones teóricas al aplicar la teoría de la Seguridad Emocional al estudio de jóvenes adultos de familias intactas y con padres divorciados, y que vivían o no con sus familias mientras estudiaban en la Universidad. Los resultados se ajustan y sustentan dicha Teoría. Igualmente tiene implicaciones prácticas para los servicios de apoyo al señalar variables familiares de riesgo y protectoras de los universitarios.

Solid-state Li-ion batteries operating at room temperature using new borohydride argyrodite electrolytes

Using a new class of (BH4)- substituted argyrodite Li6PS5Z0.83(BH4)0.17, (Z = Cl, I) solid electrolyte, Li-metal solid-state batteries operating at room temperature have been developed. The cells were made by combining the modified argyrodite with an In-Li anode and two types of cathode: an oxide, LixMO2 (M = 1/3Ni, 1/3Mn, 1/3Co; so called NMC) and a titanium disulfide, TiS2. The performance of the cells was evaluated through galvanostatic cycling and Alternating Current AC electrochemical impedance measurements. Reversible capacities were observed for both cathodes for at least tens of cycles. However, the high-voltage oxide cathode cell shows lower reversible capacity and larger fading upon cycling than the sulfide one. The AC impedance measurements revealed an increasing interfacial resistance at the cathode side for the oxide cathode inducing the capacity fading. This resistance was attributed to the intrinsic poor conductivity of NMC and interfacial reactions between the oxide material and the argyrodite electrolyte. On the contrary, the low interfacial resistance of the TiS2 cell during cycling evidences a better chemical compatibility between this active material and substituted argyrodites, allowing full cycling of the cathode material, 240 mAhg-1, for at least 35 cycles with a coulombic efficiency above 97%

Afrodescendientes en América Latina. Estudio de caso de la movilización etnopolítica afroamericana de la Costa Chica de Guerrero y Oaxaca, México (1997-2016)

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Derecho, Departamento de Ciencia Política y Relaciones Internacionales. Fecha de lectura: 26-09-201

Exactly solvable D_N-type quantum spin models with long-range interaction

We derive the spectra of the D_N-type Calogero (rational) su(m) spin model, including the degeneracy factors of all energy levels. By taking the strong coupling limit of this model, in which its spin and dynamical degrees of freedom decouple, we compute the exact partition function of the su(m) Polychronakos-Frahm spin chain of D_N type. With the help of this partition function we study several statistical properties of the chain's spectrum, such as the density of energy levels and the distribution of spacings between consecutive levels.Comment: 12 pages, 2 figure

Declarative Choreographies and Liveness

Part 1: Full PapersInternational audienceWe provide the first formal model for declarative choreographies, which is able to express general omega-regular liveness properties. We use the Dynamic Condition Response (DCR) graphs notation for both choreographies and end-points. We define end-point projection as a restriction of DCR graphs and derive the condition for end-point projectability from the causal relationships of the graph. We illustrate the results with a running example of a Buyer-Seller-Shipper protocol. All the examples are available for simulation in the online DCR workbench at http://dcr.tools/forte19

Using Machine Learning Techniques to Predict Adolescents’ Involvement in Family Conflict

[Abstract] Many cases of violence against children occur in homes and other close environments. Machine leaning is a novel approach that addresses important gaps in ways of examining this socially significant issue, illustrating innovative and emerging approaches for the use of computers from a psychological perspective. In this paper, we aim to use machine learning techniques to predict adolescents’ involvement in family conflict in a sample of adolescents living with their families(community adolescents) and adolescents living in residential care centers, who are temporarilyseparated from their families because of adverse family conditions. Participants were 251 Spanish adolescents (Mage= 15.59), of whom 167 lived in residential care and 84 lived with their families.We measured perceived interparental and family conflict, adolescents’emotional security,emotional, cognitive, and behavioral immediate responses to analog interparental conflict (IPC),and adolescents’ sociodemographic variables (i.e., age, gender). With a prediction accuracy of 65%, our results show that adolescents in residential care are not at greater risk for involvement in family conflict compared to adolescents living with their families. Age and gender are not salient predictive variables. We could identify that responses to analog IPC, adolescents’emotiona lsecurity, triangulation in IPC, and the presence of insults or blame during family disputes predict adolescents’ involvement in family conflict. These results point to variables with a potential predictive capacity, which is relevant for research and intervention.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was partially supported by projects PLEC2021-007,662 (MCIN/AEI/10.13,039/501100011033, Ministerio de Ciencia e Innovación, Agencia Estatal de Investigación, Plan de Recuperación, Transformación y Resiliencia, Unión Europea-Next GenerationEU), RTI2018-093,336-B-C21 & RTI2018-093,336-B-C22 (Ministerio de Ciencia e Innovación, Agencia Estatal de Investigación & ERDF). The fourth and fifth authors also thank the financial support supplied by the Consellería de Educación, Universidade e Formación Profesional (accreditation 2019–2022 ED431G-2019/01 and GPC ED431 B 2019/03) and the European Regional Development Fund, which acknowledges the CITIC Research Center in ICT of the University of A Coruña as a Research Center of the Galician University System. The third author also thanks the financial support supplied by the Consellería de Educación, Universidade e Formación Profesional (accreditation 2019–2022 ED431G-2019/04, ED431 C 2018/29) and the European Regional Development Fund, which acknowledges the CiTIUS-Research Center in Intelligent Technologies of the University of Santiago de Compostela as a Research Center of the Galician University SystemXunta de Galicia; ED431G-2019/01Xunta de Galicia; ED431 B 2019/03Xunta de Galicia; ED431G-2019/04Xunta de Galicia; ED431 C 2018/2

Electrooxidation of formic acid on gold : An ATR-SEIRAS study of the role of adsorbed formate

Funding from the DGI (Spanish Ministry of Education and Science) through Projects CTQ2009-07017 and PLE2009-0008 is gratefully acknowledged. M.E.-E. acknowledges an FPI fellowship from the Spanish Ministry of Science and Innovation and an accommodation grant at the Residencia de Estudiantes from the Madrid City Council. C. V.-D. acknowledges a JAE-Doc fellowship from CSIC.Peer reviewedPostprin

Inozemtsev's hyperbolic spin model and its related spin chain

In this paper we study Inozemtsev's su(m) quantum spin model with hyperbolic interactions and the associated spin chain of Haldane-Shastry type introduced by Frahm and Inozemtsev. We compute the spectrum of Inozemtsev's model, and use this result and the freezing trick to derive a simple analytic expression for the partition function of the Frahm-Inozemtsev chain. We show that the energy levels of the latter chain can be written in terms of the usual motifs for the Haldane-Shastry chain, although with a different dispersion relation. The formula for the partition function is used to analyze the behavior of the level density and the distribution of spacings between consecutive unfolded levels. We discuss the relevance of our results in connection with two well-known conjectures in quantum chaos.Comment: 22 pages, RevTeX, 7 figure

Thermodynamics of spin chains of Haldane-Shastry type and one-dimensional vertex models

We study the thermodynamic properties of spin chains of Haldane-Shastry type associated with the A_{N-1} root system in the presence of a uniform external magnetic field. To this end, we exactly compute the partition function of these models for an arbitrary finite number of spins. We then show that these chains are equivalent to a suitable inhomogeneous classical Ising model in a spatially dependent magnetic field, generalizing the results of Basu-Mallick et al. for thezero magnetic field case. Using the standard transfer matrix approach, we are able to compute in closed form the free energy per site in the thermodynamic limit. We perform a detailed analysis of the chains' thermodynamics in a unified way, with special emphasis on the zero field and zero temperature limits. Finally, we provide a novel interpretation of the thermodynamic quantities of spin chains of Haldane-Shastry type as weighted averages of the analogous quantities over an ensemble of classical Ising models.Comment: LaTeX, 39 pages, 13 figure