Revival of Bulgarian Folk Music During Socialism and the Post-Socialist Transition: Music and Cultural Identity

This article juxtaposes two periods of Bulgarian folk music revival, which were separated by a period of rejection of Bulgarian traditions and cultural values, and problematizes the success of chalga, a pan-Balkan musical phenomenon from the post-socialist period. By engaging current research of American and Bulgarian scholars and reflecting on the author’s recent fieldwork and personal experiences as a performer of Bulgarian folk music, this study raises questions regarding the relationships between state-imposed nationalism and folk traditions, village culture and modern life, the role of media in the dissemination of musical traditions, and the importance of folk music in the construction of modern Bulgarian cultural identity

Integrable mixing of A_{n-1} type vertex models

Given a family of monodromy matrices {T_u; u=0,1,...,K-1} corresponding to integrable anisotropic vertex models of A_{(n_u)-1}-type, we build up a related mixed vertex model by means of glueing the lattices on which they are defined, in such a way that integrability property is preserved. Algebraically, the glueing process is implemented through one dimensional representations of rectangular matrix algebras A(R_p,R_q), namely, the `glueing matrices' zeta_u. Here R_n indicates the Yang-Baxter operator associated to the standard Hopf algebra deformation of the simple Lie algebra A_{n-1}. We show there exists a pseudovacuum subspace with respect to which algebraic Bethe ansatz can be applied. For each pseudovacuum vector we have a set of nested Bethe ansatz equations identical to the ones corresponding to an A_{m-1} quasi-periodic model, with m equal to the minimal range of involved glueing matrices.Comment: REVTeX 28 pages. Here we complete the proof of integrability for mixed vertex models as defined in the first versio

The current crisis of academia-led research: A threat to the common good? Preliminary data from Europe and the United States

Objective: This research note aimed to analyze the scientific productivity trends 2015-2019, focusing on the top 30 universities in Europe and United States and on the top 30 private companies - as classified in the SCImago Institutions Ranking. Our hypothesis is that private companies are gaining an increasingly prominent role in the research field, while academia is losing its predominance. Results: From 2015 to 2019, all universities in Europe and the United States lost positions in the scientific production ranking, while private companies gained positions. These trends seem to be driven mainly by the scientific productivity sub-indicator "Innovation". These data suggest that the role private companies will play in the future will not be limited to support research economically or influence it from "outside". Private companies have taken a path that may lead them to directly control all stages of production/communication of knowledge, including research - a role once bestowed on universities. Our data, although preliminary, seem to suggest that, at present, academia risks losing its predominance in the research field. This scenario deserves attention because of the threats it may pose to the independence of research and its role in supporting human equity and sustainable health for all

Spectrum generating algebra for the continuous spectrum of a free particle in Lobachevski space

In this paper, we construct a Spectrum Generating Algebra (SGA) for a quantum system with purely continuous spectrum: the quantum free particle in a Lobachevski space with constant negative curvature. The SGA contains the geometrical symmetry algebra of the system plus a subalgebra of operators that give the spectrum of the system and connects the eigenfunctions of the Hamiltonian among themselves. In our case, the geometrical symmetry algebra is $\frak{so}(3,1)$ and the SGA is $\frak{so}(4,2)$. We start with a representation of $\frak{so}(4,2)$ by functions on a realization of the Lobachevski space given by a two sheeted hyperboloid, where the Lie algebra commutators are the usual Poisson-Dirac brackets. Then, introduce a quantized version of the representation in which functions are replaced by operators on a Hilbert space and Poisson-Dirac brackets by commutators. Eigenfunctions of the Hamiltonian are given and "naive" ladder operators are identified. The previously defined "naive" ladder operators shift the eigenvalues by a complex number so that an alternative approach is necessary. This is obtained by a non self-adjoint function of a linear combination of the ladder operators which gives the correct relation among the eigenfunctions of the Hamiltonian. We give an eigenfunction expansion of functions over the upper sheet of two sheeted hyperboloid in terms of the eigenfunctions of the Hamiltonian.Comment: 23 page

A human tau seeded neuronal cell model recapitulates molecular responses associated with Alzheimer's disease

Cellular models recapitulating features of tauopathies are useful tools to investigate the causes and consequences of tau aggregation and the identification of novel treatments. We seeded rat primary cortical neurons with tau isolated from Alzheimer's disease brains to induce a time-dependent increase in endogenous tau inclusions. Transcriptomics of seeded and control cells identified 1075 differentially expressed genes (including 26 altered at two time points). These were enriched for lipid/steroid metabolism and neuronal/glial cell development genes. 50 genes were correlated with tau inclusion formation at both transcriptomic and proteomic levels, including several microtubule and cytoskeleton-related proteins such as Tubb2a, Tubb4a, Nefl and Snca. Several genes (such as Fyn kinase and PTBP1, a tau exon 10 repressor) interact directly with or regulate tau. We conclude that this neuronal model may be a suitable platform for high-throughput screens for target or hit compound identification and validation

A Sustainable Multi-objective Optimization Model for Design of Supply Chain Under Uncertain Products Demands and Products Prices: a Real Case of Dairy Industry

Dairy production has a significant environmental impact related with wastewater and air pollution. In addition, it is a large consumer of water and energy. The most effective way to improve its sustainability is through analysis of the food-water-energy nexus, which can be done by optimizing all activities in the supply chain (SC) from the raw materials to the end user while meeting environmental, economic and social criteria. However, the presence of uncertainties regarding the main parameters of the SC would lead to problems related to the implementation of processes and the operating the system as a whole. To solve these problems an implementation of models for optimal design of dairy SCs that handle these uncertainties is needed. The present study proposes an extended version of already developed mixed integer non-linear programming (MINLP) approach to optimal design of a sustainable SC for the production of different dairy products according different recipes under uncertain products demands and products prices. The model has taken into account economic, environmental and social aspects. The obtained results show that the increase in the uncertainty level leads to an increase of values of economic, environmental and social costs as well as the profit, with the standard deviation of the same being the highest at the lowest level of uncertainty, while at the others it is preserved relatively constant. The number of workers employed by the supply centers, dairies and markets is kept constant regardless of the variation in the level of uncertainty of products demands and products prices