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Nuevas reflexiones sobre por qué he dejado de crear e-Literatura
Eugenio Tisselli
Caracteres : Estudios Culturales y Críticos de la Esfera Digital , 2012,
Abstract: I have stopped creating new works of e-Literature. I feel that the ethical questions which surround the creation of artworks within an electronic medium are too important to be ignored. In this essay, I reflect upon the note through which I originally announced my decision, whose main intention is to point the attention of the e-Literature community towards the serious absence of ethical assessments within the discipline. I believe these assessments should be considered and integrated as parameters for both the creation and the study of the works of e-Literature. In face of the undeniable materialness of digital technologies, whose manufacturing processes imply the dismantling of natural and social systems in different parts of the world, I believe that rethinking the relationships between literature and its new medium becomes an urgent task, which should be approached in a multidimensional way, including ethics, transdisciplinary research and critical engineering.
The Risks of Inappropriateness in Cardiac Imaging
Eugenio Picano
International Journal of Environmental Research and Public Health , 2009, DOI: 10.3390/ijerph6051649
Abstract: The immense clinical and scientific benefits of cardiovascular imaging are well-established, but are also true that 30 to 50% of all examinations are partially or totally inappropriate. Marketing messages, high patient demand and defensive medicine, lead to the vicious circle of the so-called Ulysses syndrome. Mr. Ulysses, a typical middle-aged “worried-well” asymptomatic subject with an A-type coronary personality, a heavy (opium) smoker, leading a stressful life, would be advised to have a cardiological check-up after 10 years of war. After a long journey across imaging laboratories, he will have stress echo, myocardial perfusion scintigraphy, PET-CT, 64-slice CT, and adenosine-MRI performed, with a cumulative cost of >100 times a simple exercise-electrocardiography test and a cumulative radiation dose of >4,000 chest x-rays, with a cancer risk of 1 in 100. Ulysses is tired of useless examinations, exorbitant costs. unaffordable even by the richest society, and unacceptable risks.
Mammography and beyond: developing technologies for the early detection of breast cancer
Eugenio Paci
Breast Cancer Research , 2002, DOI: 10.1186/bcr429
Abstract: Following a short presentation of the history of mammography, the theory of efficacy evaluation through randomized clinical trials (all referenced) and the more recent evaluations of screening programmes that are ongoing in several countries are critically re-examined. The second chapter discusses new developments in breast imaging and in related technologies; a table presents the current status of imaging technologies for a large number of devices, few of which are currently of interest with regard to early detection. Most of the technologies discussed pertain to clinical diagnosis, and are unlikely to surpass mammography in the field of early detection in the near future.A chapter entitled Technologies in development: genetic and tumor markers reports on the progress that has been made in this important field, but it states that "... the ability to predict who will develop breast cancer is modest at best." We are still in the realm of basic research, and application of these technologies in screening is far from reaching routine daily practice. However, the authors emphasize the opportunity to improve predictive oncology in the early stages of breast cancer. Furthermore, with private companies developing genetic tests, and the fact that "The tests are not subject to FDA [Food and Drug Administration] regulation and thus clinical validity and utility did not have to be documented before entry into the market", there is a need for a new policy and for genetic counselling for women who request testing.The following chapter on the development and regulation of new technologies (which is referred to only within the context of the USA) is original to the best of my knowledge, at least for a European audience. The narrative of the initiatives and collaborations that have been active between government agencies, private industries and associations, and the examples of funding mechanisms for medical technology development confirm the massive investment into breast cancer c
Economic and biological costs of cardiac imaging
Eugenio Picano
Cardiovascular Ultrasound , 2005, DOI: 10.1186/1476-7120-3-13
Abstract: A Renaissance of cardiac imaging occurred in the 1980s [1]. New technologies allowed the non-invasive description of cardiac function, perfusion, and metabolism in a polychrome, three-dimensional, overwhelming fashion. Almost unlimited resources were devoted to patient care in the economic framework of the affluent society. At the beginning of the 1990s, The Renaissance made its transition into the splendid decadence of the Baroque. The increasing technological burden in clinical cardiology paradoxically did not bring a parallel increase in the quality of care but rather an increase in cost. The economic climate had changed; the illusion of unlimited economic resources had come to an end [2]. Keeping in mind that each test represents a cost, often a risk, and always a diagnostic hypothesis, we can agree that every unnecessary and unjustifiable test is one test too many. Small individual costs, risks, and wastes multiplied by billions of examinations per year represent an important population [3], society [4] and environmental [5] burden. Unfortunately, the appropriateness of cardiac imaging is usually extra-ordinarily low and there is little awareness among patients and physicians of the elementary physical basis, differential costs, radiological doses, and long term risks of different imaging modalities [6]. It is also well known that – in the words of Bernard Lown – "technology in medicine is frequently untested scientifically, often applied without data relating to cost benefit, and driven by market forces rather than by patient needs." Bernard Lown, 2004 [7]."Ten years ago, medical imaging wasn't even in the radar screen for most health insurers. In 2004, it' s one of the highest cost items in a health plan's medical budget, and also one of the fastest growing". (Atlantic info service newsletter, 2004) [8]. As an example, in U.S. during the year 2002, 7.8 million cardiac perfusion scans were performed, with a growth of 40% in the last 3 years [9]. Still in U.S.,
Anniversary Editorial: One year of Cardiovascular Ultrasound
Eugenio Picano
Cardiovascular Ultrasound , 2004, DOI: 10.1186/1476-7120-2-3
Abstract: Cardiovascular Ultrasound is an Open Access, peer-reviewed online journal covering clinical, technological, experimental, biological, and molecular aspects of ultrasound applications in cardiovascular physiology and disease.Cardiovascular Ultrasound is aimed at providing a suitable tribune for the most current, clinically and biologically relevant, and high quality research in the field of ultrasound of heart and vessels. The journal publishes peer-reviewed original research, updated reviews, case reports on challenging and/or unusual diagnostic aspects, and expert opinions on new techniques and technologies. Other feature of interest to the cardiologist, the sonographer and allied scientists is the "natural born digital" nature of the journal, with the possibility to publish colour illustrations and video clips with no extra costs. This feature is especially attractive in a field so dynamic (both in a conceptual and in a cinematic sense) as ultrasound. The possibility to go immediately to Pubmed, and the publication of video-clips, will tremendously increase the scientific impact of your material. Cardiovascular Ultrasound might become a good first choice for much of your "hot material", when time is not an independent variable.The cardiovascular ultrasound community needs an Open Access forum in which to publish peer-reviewed articles with speed (in revision and publication), and versatility (in arguments, ranging from biology to engineering to clinical echocardiography). Cardiovascular Ultrasound aims to be that forum.Manuscripts must be submitted to Cardiovascular Ultrasound electronically using the online submission system. Full details of how to submit a manuscript are given in the instructions for authors. Cardiovascular Ultrasound reviews all the material it receives. About 10 % of articles are rejected after review in-house. The usual reasons for rejection at this stage are insufficient originality or serious scientific flaws. We aim to reach a decision on
Zinc and ageing: third Zincage conference
Eugenio Mocchegiani
Immunity & Ageing , 2007, DOI: 10.1186/1742-4933-4-5
Abstract: Zincage [1] is a specific targeted research project (STREP) funded by the European Union in the 6th Framework Program (FP6). It includes epidemiological studies on the influence of diet and lifestyle on healthy ageing, aimed at preventing adult degenerative disease, particularly focusing on cardiovascular diseases and also addressing malnutrition of the elderly. The conference held in Ancona, January 2007, was focussed particularly on the effects of Zn supplementation in the elderly and on the possible influences of dietary, biochemical and genetic factors on the individual response. Zn deficiency, cell-mediated immune dysfunction and increased oxidative stress are common in elderly subjects and it is quite clear that dietary habits including Zn consumption have a great impact on these factors. Zn supplementation in the elderly can improve the immune response and reduce oxidative stress markers, thereby contributing to a reduced incidence of infections. However, individual differences in the response to Zn can lead to contradictory results even with supplementation trials performed in elderly people of the same age-groups. One of the reasons for these individual differences is the different genetic background of the subjects enrolled in the study. In fact, some proteins with documented polymorphic sites are involved in regulating Zn homeostasis. One important class of such proteins are the metallothioneins (MT), which bind Zn with high affinity but, at the same time, release free Zn ions in response to oxidative/nitrosative stress and thereby modulate the expression of Zn-dependent genes and activate antioxidant enzymes. Differences in Zn status have also been observed in individuals carrying different alleles for polymorphisms of pro-inflammatory cytokines (i.e. IL-6 and TNF-alpha). In addition, the individual response can be modulated by dietary habits because Zn absorption and availability is dependent on the intake of other nutrients and trace elements.These asp
Potential emissions of Kyoto and Non-Kyoto climate active compounds in the production of sugarcane ethanol
Sanhueza,Eugenio;
Interciencia , 2009,
Abstract: sugarcane ethanol is the most commercially developed liquid biofuel. the potential emissions of kyoto and non-kyoto protocol climate active compounds in the production of sugarcane ethanol in agricultural lands are evaluated herein. various scenarios are considered, such as low or high n2o emission from n-fertilizers, inclusion or not of pre-harvest burning, uncontrolled or controlled emissions in bagasse based boilers, and 20 or 100 years time horizons in gwps. the co2 emitted in ethanol fuel combustion is recycled during sugarcane "re-growing" and does not count as greenhouse gas. however, even though many uncertainties remain, the available information allows estimating that co2-eq emissions are very large when ethanol production is based on pre-harvest burning and there is non-controlled particle emission in boilers. in these scenarios, compared with the combustion of equivalent amounts of gasoline, higher co2-eq emission would take place. halting sugarcane field burning would not be sufficient to revert the situation, especially in a 20-years time horizon. only when more environmental friendly procedures are applied, a significant saving of co2-eq emissions occurs at 20 and 100-years horizon scenarios. in all scenarios, non-kyoto protocol compounds make an important net contribution. therefore, if a real evaluation of climate active compounds emissions is to be reached, it would be crucial to include these compounds in life cycles studies. to reduce uncertainties, especially of non-kyoto compounds, additional research is needed.
Agroetanol ?un combustible ambientalmente amigable?
Sanhueza,Eugenio;
Interciencia , 2009,
Abstract: concerns about energetic security and climate change have driven the present boom of agrofuels. unfortunately, their development occurs before appropriate environmental impact studies have been made and a strong debate has been generated. the main arguments against agroethanol are reviewed herein. agrofuels have a positive net energy balance; for sugarcane ethanol it is ~8 while for corn ethanol it is <1.5; in theory, cellulosic ethanol may reach up to 36. co2 emitted by bioethanol combustion does not count as a greenhouse gas; however, during its production such gases are emitted. in the production of corn ethanol there is only a small saving of emissions. the reduction with sugarcane ethanol is very favorable when only gases included in the kyoto protocol are considered; however, when other climate active compounds are considered, co2-eq emission would surpass that produced by equivalent amounts of gasoline. agroethanol production promotes the transformation of natural soils, with loss of biodiversity and enormous co2 emissions. intensive mono-crops promote erosion, pollute waters and decrease productivity and stability of ecosystems. agrofuels compete for arable soils and are, in part, responsible for food price increases. the polemics about genetically engineering organisms will be exacerbated with the increased use of agrofuels. ethanol combustion in vehicles presents some disadvantages to gasoline, does not decrease cancer risk, increases photochemical smog in cities and increases methane emission. the eventual arrival of cellulosic ethanol could improve the situation. however, the present production potential could only replace a small percentage of liquid fossil fuels, maintaining oil dependence.
Methane soil-vegetation-atmosphere fluxes in tropical ecosystems
Sanhueza,Eugenio;
Interciencia , 2007,
Abstract: recently, a surprising discovery indicated that, by an unknown process, vegetation emits methane to the atmosphere. this finding could have serious implications in atmospheric chemistry, climate, and mitigation of global change. in order to evaluate the magnitude of the tropical vegetation source, a re-evaluation of results obtained at various venezuelan ecosystems is made. ch4 fluxes from the soil-grass system in savanna ecosystems indicate that grasses produce ch4 at ~10ng·m-2·s-1. furthermore, ch4 accumulation within the nocturnal mixing layer at the guri site, which is affected by savanna and forest emissions, was used to make a rough upper limit estimation of <70ng·m-2·s-1 for ch4 emission from forest vegetation. these estimates are likely to be somewhat low as they do not take into account the light-induced production of ch4 by the vegetation. global extrapolation of these fluxes indicates that, ignoring the possible stimulating effects of solar radiation, savanna and forest vegetation result in ch4 emissions of ~5tg·yr-1 and <22tg·yr-1, respectively. these estimates are in agreement with the lower estimates based on laboratory ch4 flux measurements, reported in the literature. on the other hand, the global extrapolation of the atmosphere-soil uptake fluxes results ch4 sinks of ~1.3tg·yr-1 in savannas and of 3.3tg·yr-1 in forests. in conclusion, venezuelan field measurements support the discovery that vegetation emits ch4. however, global extrapolation indicates that tropical vegetation would contribute modestly to global methane emission, which, additionally, is offset in part by savanna and forest ch4 soil uptake. most likely, carbon sequestration benefits from forestation should not be significantly affected by ch4 emissions by trees.
MECáNICA ESTADíSTICA, NEODARWINISMO Y LA PREFIGURACIóN DE LAS CIENCIAS DE LA COMPLEJIDAD
EUGENIO,ANDRADE;
Acta Biológica Colombiana , 2009,
Abstract: this paper aims to illustrate: 1. that for the founders of population genetics, fisher and wright, there was a close relationship between physics and biology. 2. the mathematics of population genetics aimed at placing evolutionary theory as a -hard science- at the same level as boltzmann and maxwell?s physics. 3. this effort showed that the concept of evolution by natural selection does not contradict the laws of thermodynamics that rule the evolution of physical systems. 4. the metaphor that paradoxically represents living beings as -maxwellian demons- anticipated some aspects of the present day evolutionary theories that recur to the thermodynamic of complex adaptive systems as developed by prigogine, 1970, and kauffman, 1993. 5. to conclude, i contrast darwin and einstein in order to clarify, how can be understood today, the bridges and bidirectional connections between physics and biology.
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