[Review of] Clara E. Rodriguez, ed. Latin Looks: Images of Latinas and Latinos in the U.S. Media

The anthology Latin Looks is an important contribution to the literature on Latinos and their relationship to the mass media in the United States. It builds on the earlier work by Rosa Linda Fregoso, George Hadley-Garcia, Chon Noriega, Luis Reyes, Peter Ruble, Allen Woll, and others. The book focuses primarily on television and film; however, there is no discussion of the films produced in other countries, or the Spanish language films produced in the United States. The images that are developed in music, literature, or magazines are also not discussed, although there is an admission that these are an important sources which require analysis

Afrocentrism and the Peopling of the Americas

This essay focuses on a theory of human development that has been promoted aggressively by a group of Afrocentrists in recent years - that the Western Hemisphere was first populated by Africoids or Black people who came to the Americas by way of Asia and the Bering Straits with little or no change in their physical or racial characteristics. As discussed in this article, the theory has no support in the evidence collected by scientists in various fields. The essay focuses on the basic claims and methods used by the Afrocentrists to support their theory, including their misuse or misinterpretation of mostly outdated scholarship produced in Europe and the United States during the late nineteenth and early twentieth centuries. A brief concluding section makes reference to the potential repercussions of this theory on relations between African Americans, Native Americans and Latinos of Native American and part Native American background

Exchange rate stabilization in developed and underdeveloped capital markets

The target zone model by Krugman (1991) assumes that foreign exchange intervention targets exchange rate levels. We argue that the fit of this model depends on the stage of development of capital markets. Foreign exchange intervention of countries with highly developed capital markets is in line with Krugman’s (1991) model as the exchange rate level is targeted (mostly to sustain the competitiveness of exports) and the volatility of day-to-day exchange rate changes are left to market forces. In contrast, countries with underdeveloped capital markets control both volatility of day-to-day exchange rate changes as well as long-term fluctuations of the exchange rate levels to sustain the competitiveness of exports as well as to reduce the risk for short-term and long-term payment flows. Estimations of foreign exchange intervention reaction functions for Japan and Croatia trace the asymmetric pattern of foreign exchange intervention in countries with developed and underdeveloped capital markets. JEL Classification: F31foreign exchange intervention, reactions functions, target zones, underdeveloped capital markets

Does the Impact of Oportunidades Program Increases in Highly Competitive Regions?

Evidence on Oportunidades, a successful anti-poverty program in Mexico, has suggested that changes to the current grant structure may induce considerable improvements to its effectiveness. Moreover, there are proposals addressing the importance of regional, observable and unobservable characteristics, regarding its implementation. It is employed competitiveness level outcomes to investigate if this social policy has heterogeneous performance in different regions of intervention. For this purpose, a Difference-in-Difference model is applied to estimate short and mid-term impacts on enrolment rates. Results indicate that the general competitiveness effect is positive but not robust, given the considerable level of aggregation of the data used, whereas if it is distinguised Oportunidades treatment by selected competitiveness outcomes, states with highly efficient government institutions, middle competitive economic sectors and middle inclusive, educated and healthy individuals, present a larger program impact on enrolment rates. It is confirmed the significant improvements to program effectiveness and the impact of the competitiveness variables when it is considered only a sample of older children.Social policy effectiveness, competitiveness outcomes, school enrolment rates, regional effects, difference-in-difference (DID) model

Improved Model of TiO2 Memristor

Analysis of Pickett’s model of the HP TiO2 memristor presented in this paper reveals an ambiguity of its port equation, which may cause non-convergence, numerical errors, and non-physical solutions during time-domain simulation. As there is no easy fix of the original model a new behavioral approximation of static I-V characteristics has been proposed. The approximation matches well the original model and is unambiguous

Analytical Computation of the Area of Pinched Hysteresis Loops of Ideal Mem-Elements

The memory elements, memristor being the best known of them, driven by a periodical waveform exhibit the well-known pinched hysteresis loops. The hysteresis is caused by a memory effect which results in a nonzero area closed within the loop. This paper presents an analytical formula for the loop area. This formula is then applied to memory elements whose parameter-vs.-state maps are modeled in the polynomial form. The TiO2 memristor, a special subset of the above elements, is analyzed as a demonstration example

Differential Equations of Ideal Memristors

Ideal memristor is a resistor with a memory, which adds dynamics to its behavior. The most usual characteristics describing this dynamics are the constitutive relation (i.e. the relation between flux and charge), or Parameter-vs-state- map (PSM), mostly represented by the memristance-to-charge dependence. One of the so far unheeded tools for memristor description is its differential equation (DEM), composed exclusively of instantaneous values of voltage, current, and their derivatives. The article derives a general form of DEM that holds for any ideal memristor and shows that it is always a nonlinear equation of the first order; the PSM forms are found for memristors which are governed by DEMs of the Bernoulli and the Riccati types; a classification of memristors according to the type of their dynamics with respect to voltage and current is carried out

Immediate Analysis of Periodic Steady States in Switched DC-DC Converters via SPICE

The method of immediate analysis of periodic steady states in switched DC-DC converters operating in the continuous current mode is described. The initial conditions, which correspond to the periodic steady state, are found in the first step. They are used consequently for the conventional transient analysis. A special SPICE model of the converter finds automatically these initial conditions, which are then available within the transient analysis. The method works both for the well-known behavioral models of switched converters and also for models which employ complex nonlinear SPICE models of semiconductor switches