164 research outputs found
The method of instructing children rationally in the arts of writing and reading. By J. Neef.
No full text338 p
Manfred Max Neef y la revolución ambientalista para América Latina, 1932-2019 (in memoriam)
No full textWith the article, it is offered a tribute to the work of Manfred Max Neef, Chilean intellectual,
politician, ecologist and economist, Alternative Nobel Prize winner in Economics, a pioneer in ecological
criticism of both productivism and extractivism in Latin America. The methodology used in this work
is based on the review of the main books published by the author, such as Barefoot Economy (1982),
Development on a Human Scale (1986), The Lost Dimension (2007), and The Unmasked Economy
(2014). It is held as an assumption that Max Neef’s work fits into a Latin American theoretical body,
which breaks intellectually with macroeconomic models, be they developmentalist or neoliberal in
nature. The originality of his contribution is in the defense of the ecological foundations for human
development at a local scale.Con el artículo, se ofrece un homenaje a la obra de Manfred Max Neef, intelectual, político, eco-
logista y economista chileno, Premio Nobel Alternativo en Economía, pionero en la crítica ecológica,
tanto en el productivismo como en el extractivismo en América Latina. La metodología empleada
en este trabajo se funda en la revisión de los principales libros publicados por el autor, tales como
Economía descalza (1982), Desarrollo a escala humana (1986), La dimensión perdida (2007) y La
economía desenmascarada (2014). Se sostiene como supuesto que la obra de Max Neef se encuadra
en un cuerpo teórico latinoamericano, que rompe intelectualmente con los modelos macroeconómi-
cos, sean de corte desarrollista o de tipo neoliberal. La originalidad de su aporte se encuentra en la
defensa de los fundamentos ecológicos para el desarrollo humano a una escala local
Author response: The synaptic ribbon is critical for sound encoding at high rates and with temporal precision
No full textWe studied the role of the synaptic ribbon for sound encoding at the synapses between inner hair cells (IHCs) and spiral ganglion neurons (SGNs) in mice lacking RIBEYE (RBEKO/KO). Electron and immunofluorescence microscopy revealed a lack of synaptic ribbons and an assembly of several small active zones (AZs) at each synaptic contact. Spontaneous and sound-evoked firing rates of SGNs and their compound action potential were reduced, indicating impaired transmission at ribbonless IHC-SGN synapses. The temporal precision of sound encoding was impaired and the recovery of SGN-firing from adaptation indicated slowed synaptic vesicle (SV) replenishment. Activation of Ca2+-channels was shifted to more depolarized potentials and exocytosis was reduced for weak depolarizations. Presynaptic Ca2+-signals showed a broader spread, compatible with the altered Ca2+-channel clustering observed by super-resolution immunofluorescence microscopy. We postulate that RIBEYE disruption is partially compensated by multi-AZ organization. The remaining synaptic deficit indicates ribbon function in SV-replenishment and Ca2+-channel regulation
Author response: Gender bias in scholarly peer review
No full textPeer review is the cornerstone of scholarly publishing and it is essential that peer reviewers are appointed on the basis of their expertise alone. However, it is difficult to check for any bias in the peer-review process because the identity of peer reviewers generally remains confidential. Here, using public information about the identities of 9000 editors and 43000 reviewers from the Frontiers series of journals, we show that women are underrepresented in the peer-review process, that editors of both genders operate with substantial same-gender preference (homophily), and that the mechanisms of this homophily are gender-dependent. We also show that homophily will persist even if numerical parity between genders is reached, highlighting the need for increased efforts to combat subtler forms of gender bias in scholarly publishing
Modelling Capillary Effects in Heterogeneous Porous Media
No full textElectrical Engineering, Mathematics and Computer Scienc
Instabilities of active polar fluids in the Taylor-Couette geometry and migration analysis of human immune cells
No full textEine wesentliche Eigenschaft lebendiger Materie ist ihre „Aktivität“, also die Fähigkeit, chemische in mechanische Energie umzuwandeln. Das Konzept des „aktiven polaren Fluids“ ermöglicht eine Kontinuumsbeschreibung einer Vielzahl von biologischen Systemen unter besonderer Berücksichtigung gebrochener räumlicher Symmetrien. Wir untersuchen die Dynamik eines solchen Fluids in einer planaren Taylor-Couette-Geometrie, einer ebenen Fläche, die durch konzentrische Zylinder begrenzt wird. Wir finden in Abhängigkeit von der Aktivität des Systems eine Vielzahl spontaner Strömungsmuster, insbesondere auch in Abwesenheit externer Drehmomente.
Als Beispiel für ein aktives System analysieren wir die Migration von CD8⁺ T-Zellen und Natürlichen Killerzellen (NK-Zellen), zweier wesentlicher Bestandteile des menschlichen Immunsystems. Die zugrunde liegenden in-vitro Experimente wurden von Mitarbeitern der Arbeitsgruppe Markus Hoth (Lehrstuhl für Biophysik, Universität des Saarlandes) durchgeführt. Von besonderem Interesse sind dabei die Geschwindigkeit sowie die Persistenz der Bewegungsrichtung der Zellen. Wir modellieren die Bewegung der Zellen als persistenten Random Walk mit Ruhezeiten und vergleichen dies mit alternativen Modellen.An essential property of living matter is its “Activity”, i.e. its ability to transform chemical into mechanical energy. The concept of “active polar fluids” enables us to mathematically describe a large class of such biological systems while considering broken spatial symmetries. We analyze the dynamics of an active polar fluid in a planar Taylor-Couette geometry. i.e. a planar space bounded by two concentric cylinders. Depending on the system's activity we find several classes of spontaneous flow patterns, even in the absence of external torques.
As an example of an active system, we analyze the migration of CD8⁺ T-cells as well as natural killer cells (NK cells), which are essential components of the human immune response. The in-vitro experiments have been performed by members of the group of Markus Hoth (Biophysics, Saarland University). We are especially interested in the velocities as well as the persistence of direction of the cells' motion. We model the motion as persistent random walks with resting phases and compare this model to alternative ones
Conceptualizing Contract Farming in the Global Land Grabbing Debate
No full textContract farming, a system of vertical coordination between a grower and a buyer, maintains an ambivalent position in the global land grabbing literature. It appears variously as a form of land grabbing itself, as a potentially inclusive and therefore desirable alternative to land grabbing, and as a way to organize production post-land grab. Given this ambiguity, this chapter aims to clarify conceptualizations of contract farming and land. We discuss the three approaches identified above, arguing that each suffers from a weak theorization of the phenomenon of contract farming itself. The chapter then introduces a fourth thesis that provides a deeper conceptualization of the relationship between contract farming and land, arguing that it is not analytically useful to consider contract farming as a form of land grabbing. Instead, we position contract farming as a way for capital to control land without owning land. In doing so, we invite the global land grabbing literature to engage deeply with the significant historical body of critical analysis of contract farming, including how contract farming itself shapes processes of agrarian change and socio-economic dynamics in different but equally important ways to land acquisition. We believe such a cross-fertilization of ideas about land, agricultural and agrarian change will be beneficial for both literatures
Social indicators for real-life economics
No full textDiscusses three approaches to measuring social welfare which might overcome the problems and limitations inherent in the use of GNP statistics. The first is a modified and improved GNP; the second is a quality of life (QOL) measurement arrived at either by condensing statistics into one scale or by using subjective indicators such as how happy people say they are; and the third approach uses social reports which summarise aspects of welfare but does not attempt to give a single statistic. The author argues that the first and the third lines of analysis are of most value and suggest a four-component indicator framework. This comprises: environmental and resource accounts; an adjusted National Product; a household production account; and a social indicator framework. -M.Amos</p
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