Export Growth and Factor Market Competition: Theory and Evidence

Empirical evidence suggests that sectoral export growth decreases exporters\' survival probability, whereas non{exporters are unaffected. Models with firm heterogeneity in total factor productivity predict the opposite. To solve this puzzle, we develop a two-factor framework where firms differ in factor shares. In this model, export growth increases competition for the factor used intensively by exporters, eliminating some of them, while non-exporters benefit. Our empirical analysis shows that the forces highlighted in the model drive the firm selection experienced by the Chilean manufacturing sector, suggesting that heterogeneity in factor shares is crucial to understand how firms react to trade liberalization.Firm Dynamics, Two-Factor Trade Model, Firm Heterogeneity in Factor Shares, Chile, Manufacturing Industry

Temporal disorder in up-down symmetric systems

The effect of temporal disorder on systems with up-down Z2 symmetry is studied. In particular, we analyze two well-known families of phase transitions: the Ising and the generalized voter universality classes, and scrutinize the consequences of placing them under fluctuating global conditions. We observe that variability of the control parameter induces in both classes "Temporal Griffiths Phases" (TGP). These recently-uncovered phases are analogous to standard Griffiths Phases appearing in systems with quenched spatial disorder, but where the roles of space and time are exchanged. TGPs are characterized by broad regions in parameter space in which (i) mean first-passage times scale algebraically with system size, and (ii) the system response (e.g. susceptibility) diverges. Our results confirm that TGPs are quite robust and ubiquitous in the presence of temporal disorder. Possible applications of our results to examples in ecology are discussed

Active split-ring metamaterial slabs for magnetic resonance imaging

In this work, it is analyzed the ability of split-ring metamaterial slabs with zero/high permeability to reject/confine the radiofrequency magnetic field in magnetic resonance imaging systems. Using an homogenization procedure, split-ring slabs have been designed and fabricated to work in a 1.5T system. Active elements consisting of pairs of crossed diodes are inserted in the split-rings. With these elements, the permeability of the slabs can be automatically switched between a unity value when interacting with the strong excitation field of the transmitting body coil, and zero or high values when interacting with the weak field produced by protons in tissue. Experiments are shown for different configurations where these slabs can help to locally increase the signal-to-noise-ratio.Comment: 6 pages, 4 figure

Strange matter in the universe

The strange quark matter hypothesis is one of the most exciting speculations of the XX Century Physics. If this hypothesis is correct, the ground state of the matter would be the strange matter, which could form the core of compact objects like neutron stars or even more exotic objects like quarks stars. Due to the high-density and low-temperature regime in these stars, the interaction between quarks through gluon exchange could favor the appearance of a color superconducting state, significantl modifying the equation of state of the system. In this paper we present a general overview of this Subject, taking also into account the effect of strong magnetic field in the quark stars

Good-bye email, welcome Slack

[EN] Email is the standard in communication with university students; as a one-to-one communication device, students repeat their doubts along multiple messages, multiplying the teacher's work and preventing the participation and learning of other students. The topic forums on virtual campuses allow better a management of doubts but require the active participation of all the students to achieve a final outcome. We propose to abandon the email and traditional forums of the campuses and enter tools with a higher professional profile to manage communication with the students. The results of this first experience, carried out with more than 90 postgraduate students, encourage its mass employment in both undergraduate and postgraduate. The survey conducted over 102 students in three different subjects of two different MSc shows how Slack, the tool we used, has been highly valued, with differences depending on the studies but neither on the gender nor on the intensity of use of the social networks.Lopez-Zafra, JM.; De Paz-Cobo, S.; Queralt Sánchez, RA. (2020). Good-bye email, welcome Slack. En 6th International Conference on Higher Education Advances (HEAd'20). Editorial Universitat Politècnica de València. (30-05-2020):635-642. https://doi.org/10.4995/HEAd20.2020.11119OCS63564230-05-202

Composición química de la Alcachofa de Tudela a lo largo de su desarrollo.

En el presente trabajo se ha estudiado la composición química -K, N, Ca, P, Mg, Fe, Mn, Zn y Cu- de la planta entera de alcachofa de Tudela, a lo largo de todas las fases de su ciclo vital, cultivada sobre suelo agrícola, en dos parcelas distintas. Así mismo, se han realizado dos análisis completos de los suelos de ambas parcelas. Con este estudio se pretende adquirir un conocimiento básico que pueda servir de comparación en otros estudios aplicados con vistas a la denominación de calidad. Se ha observado que cerca del 55% de variación de la diversidad del conjunto de los contenidos en elementos a lo largo del ciclo vital, queda explicada por N, P, Zn y Cu, y un 29% por Mn, Ca y K; el Mg y Fe tienen comportamiento diferente en las plantas de las distintas parcelas. Y además que, existe una gran similitud en las concentraciones de los 9 elementos en las distintas alcachofas

Prospectus, August 21, 2013

OBAMA SIGNS STUDENT LOAN DEAL; States tightening rules on college loans; College survival guide money matters: How to survive your first year on campus - without going broke; Essential skills for college freshmen; Boosting inclusion on campus; Are humans hard-wired for racial prejudice?; Tanney\u27s shot at the real thinghttps://spark.parkland.edu/prospectus_2013/1009/thumbnail.jp