Regional Economic Development and Mexican Out-Migration

This paper shows evidence of positive effects in the economic development of sending communities in Mexico due to migration. The principal hypothesis of this study is that remittances, knowledge and experience acquired by migrants during their migratory cycle, can be translated into larger economic growth in the out migration municipalities. This result presupposes that Government could create complementary incentives to take advantage of profitable activities. Economic and migration data for each municipality is used which allows to associate characteristics of communities, migratory flows and the effects in profitable activities. There are three sections. A first section describes the sending municipalities according to migratory intensity and their urban /rural nature. The second section analyzes the relation between remittances and socioeconomic conditions of the communities. In a third section the effect over time is estimated, relating per capita income growth and migratory flows intensity. The most relevant results are the existence of income convergence over time between high and low migration municipalities in the North and South of Mexico. As well, we find a positive and significant relation between per capita income growth and the percentage of households that receive remittances across communities, both at the country level and for the northern and southern regions separately.

La organización industrial, productividad y estrategias empresariales en México

This work adjusts the conventional industrial organization concepts to include the evolutionary approach that characterises sectors according to major trends of technical change, estimating sectoral changes of total factor productivity. The first section shows estimates of high concentration in Mexican industry, but identifies a wide variety of competitive conditions and of competitive factors according to the industrial sectors and the dominant economic agents. In the second section we further explore the importance of alternative productive strategies for foreign and national firms, and consider these in the context of the national system of innovation. Major agents in the analysis are transnational corporations (TNC) and large domestic conglomerates competing in export markets. The competitive success can be based in productivity gains, though these are not necessarily related to new investment modernization measures. In fact, there are many industries, and many of them in control of TNC, where productivity advances through the rationalization of idle capacity and the new design of existing plants. The two kinds of competitive strategy imply very different effects on the long term growth, and most notably on their distinct contribution to the domestic integration of industrial clusters, including traditional industries and science and technology related industries.

Productividad, desarrollo tecnológico y competitividad exportadora en la industria mexicana

El exitoso crecimiento de las exportaciones manufactureras mexicanas durante la década pasada se ha atribuido a varios factores y medidas de política, derivadas de los programas de ajuste estructural y apertura externa que se han puesto en práctica. Entre los cambios que contribuyen a aumentar la competitividad exportadora mexicana, como en otras partes, se postulan los incrementos en la productividad (total y del trabajo) y la liberalización de los flujos de tecnología. En la explicación más convencional de los determinantes del comercio, ambos factores deben resultar en ganancias de la competitividad, y por tanto en aumento de las exportaciones. No obstante la persuasión intuitiva de dichos argumentos, los datos recientes no los confirman. De hecho, aquí mostraremos que la dirección de causalidad entre aumento de exportaciones y ganancias de competitividad corre en la dirección contraria, porque son las exportaciones las que aumentan en realidad la competitividad de las industrias exportadoras y no al revés, como la teoría postula. Este resultado abre nuevas incógnitas respecto de los determinantes de la capacidad exportadora, dudas para las que aquí sugerimos algunas explicaciones tentativas.

Goals and challenges in hybrid software development approaches

The number of companies that use agile methods increases steadily. However, these companies often do not implement a pure agile approach but combine agile and plan-based methods to so-called hybrid development approaches. However, the development of these approaches is rather difficult for the companies, since agile and plan-based approaches often follow opposite concepts. To benefit from agile and plan-based approaches at the same time, the companies have to identify and address the conflicts between agile and plan-based methods. The conflicts depend on the goals that are pursued with the implementation of agile and plan-based methods. However, there is no overview of the exact goals that are pursued in hybrid approaches and which challenges and conflicts arise with them. Therefore, we conducted a systematic mapping study to gather and analyze the goals and challenges in hybrid development approaches. The mapping study is focused on literature that presents the actual needs and goals of companies and projects. Based on our results, we present the influence factors that cause conflicts in hybrid approaches and discuss how these conflicts can be addressed

Crystallographically Defined Silicon Macropore Membranes

Laser ablation with nanosecond-pulsed Nd:YAG laser irradiation combined with anisotropic alkaline etching of Si wafers creates 4–20 µm macropores that extend all the way through the wafer. The walls of these macropores are crystallographically defined by the interaction of the anisotropy of the etchant with the orientation of the single-crystal silicon substrate: rectangular/octagonal on Si(001), parallelepiped on Si(110), triangular/hexagonal on Si(111). Laser ablation can create pillars with peak-tovalley heights of over 100 µm. However, with nanosecondpulsed irradiation at 532 nm, the majority of this height is created by growth above the original plane of the substrate whereas for 355 nm irradiation, the majority of the height is located below the initial plane of the substrate. Repeated cycles of ablation and alkaline etching are required for membrane formation. Therefore, irradiating with 355 nm maintained better the crystallographically defined nature of the through-pores whereas irradiation at 532 nm led to more significant pore merging and less regularity in the macropore shapes. Texturing of the substrates with alkaline-etching induced pyramids or near-field modulation of the laser intensity by diffraction off of a grid or grating is used to modulate the growth of ablation pillars and the resulting macropores. Texturing causes the macropores to be more uniform and significantly improves the yield of macropores. The size range of these macropores may make them useful in single-cell biological studies

La estructura industrial y comercial de los Estados Unidos: reflexiones para el estudio de la internacionalización de la producción

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Crystallographically Determined Etching and Its Relevance to the Metal-Assisted Catalytic Etching (MACE) of Silicon Powders

Metal-assisted catalytic etching (MACE) using Ag nanoparticles as catalysts and H2O2 as oxidant has been performed on single-crystal Si wafers, single-crystal electronics grade Si powders, and polycrystalline metallurgical grade Si powders. The temperature dependence of the etch kinetics has been measured over the range 5–37◦C. Etching is found to proceed preferentially in a h001i direction with an activation energy of ∼0.4 eV on substrates with (001), (110), and (111) orientations. A quantitative model to explain the preference for etching in the h001i direction is developed and found to be consistent with the measured activation energies. Etching of metallurgical grade powders produces particles, the surfaces of which are covered primarily with porous silicon (por-Si) in the form of interconnected ridges. Silicon nanowires (SiNW) and bundles of SiNW can be harvested from these porous particles by ultrasonic agitation. Analysis of the forces acting between the metal nanoparticle catalyst and the Si particle demonstrates that strongly attractive electrostatic and van der Waals interactions ensure that the metal nanoparticles remain in intimate contact with the Si particles throughout the etch process. These attractive forces draw the catalyst toward the interior of the particle and explain why the powder particles are etched equivalently on all the exposed faces