Causas emocionales y dinámicas de las actuales expectativas en Neurociencia

Los avances de las últimas dos décadas en el estudio del sistema nervioso y en el desarrollo de neuro-tecnología parecen justificar las elevadas expectativas en lo que a este campo concierne. No obstante, cada vez son más los autores que advierten, desde dentro y fuera de la neurociencia, que es excesivo tal grado de optimismo así como perjudicial el neuro-esencialismo que genera. En el presente artículo analizamos el origen y el papel de las expectativas neurocientíficas. En las conclusiones defendemos, primero, que las principales causas no son las evidencias y las teorías científicas, como suele pensarse y, segundo, que precisamente esta generalizada falsa creencia perjudica seriamente el avance científico y el progreso social

Del escepticismo al misticismo científico. El itinerario de Aldous Huxley

Aldous Huxley vivió un periodo muy particular del siglo XX, uno en el que el debate entre racionalistas y escépticos marcó a toda una generación. Precisamente, ese fue el gran tema en torno al que girarían sus principales ensayos literarios y filosóficos. Es también en ese contexto donde hay que encuadrar el crucial papel que otorgó a la biotecnología en el progreso individual y social. No obstante, Huxley avisa de los peligros que de la biotecnología pueden derivarse de no lograr conciliar la postura del mundo objetivo con la del mundo de la vida. El autor de Un mundo feliz propuso como remedio a dicho divorcio y como prevención a los males que estaban por venir el devolver la unidad perdida a las ciencias y, en último término, al hombre. En dicha tarea, el hecho religioso, lejos de quedar excluido, es considerado un elemento sine qua non en todo proyecto interdisciplinar y vital. Es por ello que, para Huxley, todo el que aspira a la unidad intelectual debe quedar comprometido existencialmente. Como no podía ser de otra manera, esta conclusión es fruto de su extraordinaria trayectoria vital: partiendo de una posición escéptica marcada por la crítica a la racionalidad científico-tecnológica y a la religión, Huxley terminará convirtiéndose a un misticismo abierto y dialogante para con el discurso científico. La actitud de Huxley con respecto a la ciencia no es novedosa, por lo menos si valoramos en algo la filosofía premoderna. Aún y todo, Huxley presenta este ideal --el de la Filosofía perenne, como lo denomina-- con aires nuevos y accesibles para una sociedad donde los signos del pesimismo y del desconcierto eran cada vez más patentes. En tanto que esos signos son hoy visiblemente manifiestos, reflexionar sobre la vida-pensamiento de quien es uno de los más clarividentes, transgresores y obstinados intelectuales del siglo XX, resulta un ejercicio fecundo, por lo menos para quienes no han renunciado a la senda interdisciplinar. Ofrecer contenidos para dicha reflexión es el objetivo último de nuestro artículo.Aldous Huxley lived in a very particular period of the twentieth century, one in which the debate between rationalists and skeptics marked an entire generation. Indeed, it was the central issue around which his primary literary and philosophical work evolved. It is also in this context that we should frame the crucial role he afforded to biotechnology in individual and social progress. Nevertheless, Huxley warns of the dangers to be derived from biotechnology for failing to reconcile the stance of the objective world with that of the world of life. The author of Brave New World proposed returning that lost unity to the sciences and, ultimately, to mankind as a remedy for that divorce and to prevent the ills that were to come. In this task, the religious factor, far from being excluded, is considered a sine qua non of any interdisciplinary and life project. Accordingly, for Huxley, one who aspires to intellectual unity must be existentially committed. It could not be otherwise. This conclusion is the result of the extraordinary course of his life. Starting from a skeptical position marked by criticism of scientific-technological rationality and religion, Huxley converted in the end to an open and dialoguing mysticism for scientific discourse. Huxley's attitude with respect to science is not new, at least if we place any value in pre-modern philosophy. Still and all, he presents this ideal -- that of perennial philosophy, as it is called -- with a new air and as being accessible to a society where the signs of pessimism and confusion were increasingly evident. To the extent these signs are visibly manifest today, reflecting on the life and thinking of one of the most clear-signed, contravening and exasperating intellectuals of the twentieth century is a fruitful exercise, at least for those who have not renounced the interdisciplinary path. Offering substance for that reflection is the ultimate goal of this article

Las multifacéticas remolachas: una reevaluación de sus posibilidades productivas a la luz de los conocimientos actuales

La especie Beta vulgaris subsp. vulgaris comprende a las comúnmente llamadas remolachas, de las que existen tres tipos: hortícola, azucarera y forrajera. Aunque el principal órgano de interés es en todos los casos la raíz engrosada, las tres remolachas constituyen cultivos muy diferentes entre sí, tanto en cuanto a sus características agronómicas como a los productos que se obtienen de ellos, por lo que generalmente se han estudiado por separado. Sin embargo, la capacidad de esta especie de acumular en sus raíces altas concentraciones de compuestos bioactivos valiosos, junto con su probada adaptación a vastas áreas de clima templado han incentivado recientemente a escala global el interés por su cultivo, en concordancia con la creciente preocupación por la salud humana, la calidad de la alimentación y el cuidado del medioambiente. Este renovado interés plantea la necesidad de revisar el estado actual del conocimiento sobre la ecofisiología de los tres tipos de remolacha, de modo de contar con herramientas que permitan optimizar la productividad y la calidad de los productos obtenidos. En la presente revisión se realiza un análisis integrador de la información actualmente disponible sobre los distintos tipos de remolacha. Para ello, se reseñan las nuevas posibilidades de utilización, se analiza comparativamente la ecofisiología de los distintos tipos a lo largo del ciclo de cultivo, y se evalúan los aspectos críticos de la producción y calidad para cada uso. Muchos de los nuevos usos propuestos involucran a la remolacha hortícola, de la cual la información ecofisiológica disponible es relativamente escasa. Finalmente, se analiza en qué medida los conocimientos existentes acerca de un tipo de remolacha son extrapolables a los otros, y se discuten los estudios que podrán ser necesarios para en última instancia facilitar la difusión y adopción de los cultivos de remolacha con diferentes propósitos.The species Beta vulgaris subsp. vulgaris includes the so-called beets, of which there are three types, red (vegetable) beet, sugar beet and forage beet. Although in every case the main organ of agronomic interest is the storage root, the three beet types constitute very different crops, both in terms of crop characteristics and products obtained. This may be the reason why they have generally been studied separately. The ability of this species to accumulate in its roots bioactive compounds at high concentration, together with its proven adaptation to vast areas of temperate climate, have prompted global interest in its cultivation. This is also supported by a growing concern for human health, food quality and care for the environment. This renewed interest raises the need to review the current state of knowledge about the ecophysiology of the three beet types, which in turn may provide tools that will allow optimizing crop productivity and quality. In the present review, an integrative analysis of the information currently available on the different types of beet is carried out, and new possibilities of beet utilization are outlined. The ecophysiology of the three beet types is comparatively analyzed throughout the growth cycle, and critical aspects of production and quality are analyzed for the different crop purposes. Many of the proposed new uses involve red beets, for which eco-physiological information available is relatively scarce. Finally, it is discussed up to what extent the existing knowledge about one type can be extrapolated to the others, and which studies may be needed to maximize crop achievements, and ultimately, facilitate adoption of beet crops for different purposes.EEA BalcarceFil: Rattin, Jorge Edgardo. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.Fil: Echarte, María Mercedes. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina.Fil: Echarte, María Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Echarte, María Mercedes. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.Fil: Barrera, L. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.Fil: Tognetti, Jorge. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Tognetti, Jorge. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires; ArgentinaFil: Di Benedetto, Adalberto. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Di Benedetto, Adalberto. Universidad de Buenos Aires. Facultad de Agronomía; Argentin

On the structure of maximal solvable extensions and of Levi extensions of nilpotent algebras

We establish an improved upper estimate on dimension of any solvable algebra s with its nilradical isomorphic to a given nilpotent Lie algebra n. Next we consider Levi decomposable algebras with a given nilradical n and investigate restrictions on possible Levi factors originating from the structure of characteristic ideals of n. We present a new perspective on Turkowski's classification of Levi decomposable algebras up to dimension 9.Comment: 21 pages; major revision - one section added, another erased; author's version of the published pape

Specific Visualization of Glioma Cells in Living Low-Grade Tumor Tissue

BACKGROUND: The current therapy of malignant gliomas is based on surgical resection, radio-chemotherapy and chemotherapy. Recent retrospective case-series have highlighted the significance of the extent of resection as a prognostic factor predicting the course of the disease. Complete resection in low-grade gliomas that show no MRI-enhanced images are especially difficult. The aim in this study was to develop a robust, specific, new fluorescent probe for glioma cells that is easy to apply to live tumor biopsies and could identify tumor cells from normal brain cells at all levels of magnification. METHODOLOGY/PRINCIPAL FINDINGS: In this investigation we employed brightly fluorescent, photostable quantum dots (QDs) to specifically target epidermal growth factor receptor (EGFR) that is upregulated in many gliomas. Living glioma and normal cells or tissue biopsies were incubated with QDs coupled to EGF and/or monoclonal antibodies against EGFR for 30 minutes, washed and imaged. The data include results from cell-culture, animal model and ex vivo human tumor biopsies of both low-grade and high-grade gliomas and show high probe specificity. Tumor cells could be visualized from the macroscopic to single cell level with contrast ratios as high as 1000: 1 compared to normal brain tissue. CONCLUSIONS/SIGNIFICANCE: The ability of the targeted probes to clearly distinguish tumor cells in low-grade tumor biopsies, where no enhanced MRI image was obtained, demonstrates the great potential of the method. We propose that future application of specifically targeted fluorescent particles during surgery could allow intraoperative guidance for the removal of residual tumor cells from the resection cavity and thus increase patient survival

Temporal and Spatial Profiling of Root Growth Revealed Novel Response of Maize Roots under Various Nitrogen Supplies in the Field

A challenge for Chinese agriculture is to limit the overapplication of nitrogen (N) without reducing grain yield. Roots take up N and participate in N assimilation, facilitating dry matter accumulation in grains. However, little is known about how the root system in soil profile responds to various N supplies. In the present study, N uptake, temporal and spatial distributions of maize roots, and soil mineral N (Nmin) were thoroughly studied under field conditions in three consecutive years. The results showed that in spite of transient stimulation of growth of early initiated nodal roots, N deficiency completely suppressed growth of the later-initiated nodal roots and accelerated root death, causing an early decrease in the total root length at the rapid vegetative growth stage of maize plants. Early N excess, deficiency, or delayed N topdressing reduced plant N content, resulting in a significant decrease in dry matter accumulation and grain yield. Notably, N overapplication led to N leaching that stimulated root growth in the 40–50 cm soil layer. It was concluded that the temporal and spatial growth patterns of maize roots were controlled by shoot growth and local soil Nmin, respectively. Improving N management involves not only controlling the total amount of chemical N fertilizer applied, but also synchronizing crop N demand and soil N supply by split N applications