11.4.06

Agua, Usos y Abusos. La hidroelectricidad en Mesoamerica.



Gian Carlo Delgado-Ramos
(Ceiich, Unam., 2006)

Este es el más reciente título publicado por el autor. Se trata de un libro editado por el Centro de Investigaciones Interdisciplinarias en Ciencias y Humanidades de la Universidad Nacional Autónoma de México.

Sinópsis:

La gradual pérdida de reservas de agua dulce de buena calidad debido a su contaminación, la relocalización de eses reservas como producto del calentamiento global y los ecológicamente insostenibles ritmos de consumo que amenazan con aumentar, son algunos factores que dificultan cada vez más el acceso al vital líquido. no es casual entonces que desde finales del siglo XX, el agua dulce sea considerada un recuros particularmente estratégico que viene revalorando los espacios geográficos con abundancia del líquido, de por sí heterogéneos. Tal ventaja comparativa hídrica de los espacios geográficos, de frente a la variedad de usos del agua, se perfila como una característica de trascendencia, en términos político-económicos y vitales (sociales-ecológicos).
Agua: usos y abusos, indaga los proyectos y potenciales escenarios de acceso, control y usufructo de las principales reservas de agua en la región, a partir de examinar los diferentes aspectos que conforman la apropiación privada del líquido por medio de la construcción de represas y otras infraestructuras hídricas que, en el grueso de los casos, figuran como parte nodal del emplazamiento de "corredores de desarrollo" (dígase productivos, económicamente hablando). La amplia revisión de documentos oficiales y de denuncia popular que aporta una base informativa sólida al presente volumen permite ofrecer al lector un mapeo de los proyectos y escenarios abordados, así como un nítido análisis de los actores involucrados y sus intereeses. El propósito: presentar con relativa precisión el rompecabezas de la ecología política del agua en Mesoamérica.

"...de suma importancia para fortalecer nuestra lucha contra los planes imperialistas de explotación y saqueo de los recursos naturales de nuestra región." --Frente Petenero Contra Represas

Para escuchar el programa de radio del autor sobre "El carácter estratégico del agua en el mundo del siglo XXI" véase:
http://www.iiec.unam.mx/enlace_a_programas_de_radio/200603S4.mp3


***Para más información sobre las publicaciones del autor y vínculos de publicaciones en la web, véase:
http://base.google.com/base/search?q=gian+delgado&btnG=Search+Base ***

Magazine on European Research


Down to the nearest billionth
Magazine on European Research No. 47, enero 2006.

"There is plenty of room at the bottom," the US physicist and 1965 Nobel prizewinner Richard Feynman declared back in 1959. This witticism was his way of saying that there was nothing – save for the lack of suitable tools – to prevent scientists one day from working directly on the atomic scale. The world would then witness a revolution, with researchers breaking free of the confines of conventional physics to enter a universe governed by the rules of quantum physics. That day has now arrived – over the past decade the ‘nano’ prefix has been applied to activities in a wide range of fields that involve studies or operations on the atomic scale.


The suitable tools began to appear in the 1980s when a team of researchers in Zurich developed a new family of microscopes(1) enabling them to observe and handle individual atoms. It was not long before these tools spread from the physics laboratories to applications in other fields. Thus, from 1995, the double concept of nanosciences and nanotechnologies emerged progressively – terms coined in reference to the nanometre, a unit of measurement equivalent to one billionth of a metre, or the space occupied by ten atoms of average size.

All the rage
Over the past decade, the ‘nano’ has been ‘all the rage’ in the research world, with conferences, journals, seminars and patents all dedicated to the concept. It has also given rise to a growing number of neologisms – nanoparticles, nanomachines, nanomaterials, nanoelectronics, nanochemistry, nanotechnology, nanomedicine, etc. – which refer to activities that involve the study or handling of living or inanimate matter on the atomic scale. These ‘nano approaches’ are seen as revolutionary in the sciences and technologies whose applications are transforming our everyday lives. “Nanotechnologies hold the promise of stimulating economic growth by creating new products that improve the quality of life in nearly all fields,” believes Renzo Tomellini of the Nanosciences and Nanotechnologies Unit at the European Commission’s Research Directorate-General(2).

But why does this focus on the nanoworld and its new vocabulary have such particular resonance today? The answer varies depending on the discipline. In the field of physics or chemistry, for example, it is clear that the usual properties of materials, such as their conductivity or fusion point, change when one reaches the nanometric scale, at which point they are governed by the laws of quantum physics. This change of scale also has important practical consequences. Transistors are one example. In a few years’ time, their miniaturisation will come up against the physical limit of the size of the silicon atoms, below which it will not be possible to descend. Electronics will therefore have to be rethought in quantum terms, thereby opening up a whole new field of research. Another example is chemistry, or materials science, where nanotechnologies have opened up exciting new prospects for designing new forms of matter by assembling molecules one by one.

Enthusiasm and prudence in biology
In the field of biology, opinions are divided. “Yes,” asserts Kees Eijkel of the University of Twente (the Netherlands), “the nano approach is revolutionary because it makes it possible to think of life as a very complex nanotechnological system constructed as a result of a series of self-assembly processes.” But Rogério Gaspar, of Coimbra University (Portugal), is more modest in his claims: “Nanotechnologies simply repeat the former approaches on a smaller scale”. As to Shimshon Belkin of the Hebrew University of Jerusalem, he cleverly sidesteps without coming down on one side or another: “I studied microbiology at university and I am told that what I am doing now is nanobiology. Does this change of prefix have anything to do with promoting the concept I wonder?”

But there is one point on which the majority of researchers agree and that is the medical benefits that can be expected, whether or not there is any change in the scientific paradigm. Yet here too there remains a certain ‘modesty’ in the face of some announcements that could ultimately result in disappointments. “By making it possible to bring together what were previously isolated technologies, nanotechnologies promise dramatic progress in the field of the early detection of tumours and cancer treatment,” confirms Mauro Ferrari, Head of nanotechnologies at the National Cancer Institute (USA), whose aim is to reduce cancer deaths dramatically “by 2015”.

But it should also be remembered that it was President Nixon who announced – back in 1971 – that cancer would be eradicated within 20 years. And the biologists of the 1980s were rather too quick to announce gene therapy by the year 2000, too. This mythical year is now behind us and, although promising, the technique is still at the research stage. “There is widespread confusion between the reality of nanotechnologies (in the short term), their potential (in the medium and long term) and the stuff of science fiction,” explains Gian Carlo Delgado Ramos of the Autonomous University of Barcelona, who subtly adds “and no doubt not only on the part of the general public”.

Realistic prospects
One can nevertheless venture to make certain predictions as to what the most likely progress in the field of nanomedicine will be – which is precisely the mission of two joint initiatives launched earlier this year with the support of the European Commission.

In September 2005, the new Nanomedicine Technology Platform, an assembly of some 40 experts with their roots in academic or industrial research, presented its Vision Paper for 2020 which sets out the expected changes. The essential basis for its predictions is the belief that, in the future, nanotechnologies will make it possible to “carry out complex repairs at the cell level inside the human body” because “artificial nanostructures have the unique property, due to their size, of being able to interact with biomolecules on the surface of the cell and inside it”. As a result, these specialists anticipate developments in three principal fields: diagnostics (including imaging), the targeted and controlled release of medicines in diseased organs and, finally, regenerative medicine.

The year 2005 also saw the third annual EuroNanoForum(3), held in Edinburgh (Scotland) in September, at which these three subjects were central to the debates.

In a context where the economies of the developed countries are all facing growing health expenditure linked to ageing populations, it is not difficult to understand why nanomedicine is viewed as highly significant for public health, a key issue for research policy-makers and a strategic market for the pharmaceutical industry.

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