1,815 research outputs found
CALCULATION OF TEMPERATURE RISE IN DEEPLY BURIED RADIOACTIVE CYLINDERS
Temperatures were calculated relative to the storage of radioactive solid waste as a function of time and radial distance for radioactive solid cylinders in infinite solid media of "average soil," "average rock," and salt. A resistance at the cylinder--infinite medium boundary was included in the form of an air space. For the range of parameters used and withia the practical limits of accuracy, the maximum temperature rise increased linearly with the heat generation rate. The fission product spectrum was not significant in the determination of the maximum temperature rise. Under the pessimistic storage conditions assumed, the storage of cylinders of a practical size appears feasible without excessive temperature rise. A maximum temperature rise of 1000 deg F would be produced with an initial heat generation rate of 1300 to 1600 Btu/hr-ft/ sup 3/ for cylinders with a 5-in. radius, with 350 to 450 Btu/hr-ft/sup 3/ for a 10-in. radius, and with 175 to 210 Btu/hr-ft/sup 3/ for a 15-in. radius, assuming a thermal conductivity of the radioactive cylinder of 0. 1 Btu/hr-ft- deg F. (auth
tRNA-Dependent Active Site Assembly in a Class I Aminoacyl-tRNA Synthetase
AbstractThe crystal structure of ligand-free E. coli glutaminyl-tRNA synthetase (GlnRS) at 2.4 Å resolution shows that substrate binding is essential to construction of a catalytically proficient active site. tRNA binding generates structural changes throughout the enzyme, repositioning key active site peptides that bind glutamine and ATP. The structure gives insight into longstanding questions regarding the tRNA dependence of glutaminyl adenylate formation, the coupling of amino acid and tRNA selectivities, and the roles of specific pathways for transmission of tRNA binding signals to the active site. Comparative analysis of the unliganded and tRNA-bound structures shows, in detail, how flexibility is built into the enzyme architecture and suggests that the induced-fit transitions are a key underlying determinant of both amino acid and tRNA specificity
Systems and Methods for Behavior Detection Using 3D Tracking and Machine Learning
Systems and methods for performing behavioral detection using three-dimensional tracking
and machine learning in accordance with various embodiments of the invention are
disclosed. One embodiment of the invention involves a the classification application that
directs a microprocessor to: identify at least a primary subject interacting with a secondary
subject within a sequence of frames of image data including depth information; determine
poses of the subjects; extract a set of parameters describing the poses and movement of at
least the primary and secondary subjects; and detect a social behavior performed by at least
the primary subject and involving at least the second subject using a classifier trained to
discriminate between a plurality of social behaviors based upon the set of parameters
describing poses and movement
Intestinal epithelial cell-intrinsic deletion of Setd7 identifies role for developmental pathways in immunity to helminth infection
The intestine is a common site for a variety of pathogenic infections. Helminth infections continue to be major causes of disease worldwide, and are a significant burden on health care systems. Lysine methyltransferases are part of a family of novel attractive targets for drug discovery. SETD7 is a member of the Suppressor of variegation 3-9-Enhancer of zeste-Trithorax (SET) domain-containing family of lysine methyltransferases, and has been shown to methylate and alter the function of a wide variety of proteins in vitro. A few of these putative methylation targets have been shown to be important in resistance against pathogens. We therefore sought to study the role of SETD7 during parasitic infections. We find that Setd7-/- mice display increased resistance to infection with the helminth Trichuris muris but not Heligmosomoides polygyrus bakeri. Resistance to T. muris relies on an appropriate type 2 immune response that in turn prompts intestinal epithelial cells (IECs) to alter differentiation and proliferation kinetics. Here we show that SETD7 does not affect immune cell responses during infection. Instead, we found that IEC-specific deletion of Setd7 renders mice resistant to T. muris by controlling IEC turnover, an important aspect of anti-helminth immune responses. We further show that SETD7 controls IEC turnover by modulating developmental signaling pathways such as Hippo/YAP and Wnt/β-Catenin. We show that the Hippo pathway specifically is relevant during T. muris infection as verteporfin (a YAP inhibitor) treated mice became susceptible to T. muris. We conclude that SETD7 plays an important role in IEC biology during infection
Tourmaline records the hydrothermal events related to Zn-Pb mineralization around the Murguía diapir (Basque Cantabrian Basin, N Spain)
The chemical composition of tourmaline has been used as a host environment register as well as a potential exploration tool for mineral deposits. In this study, the textural and chemical composition of tourmalines associated with Zn-Pb mineralizations around the Murguía diapir (Basque Cantabrian Basin, N Spain) are examined to verify if they record the mineralizing events in the area. Petrographically, tourmalines have been differentiated between inherited and authigenic. Colorless authigenic tourmalines are present as halos partially around green and pleochroic detrital grains or as individual crystals. Inherited and authigenic tourmalines are also chemically distinct. Authigenic tourmalines show different X-site occupancies, a Mg/(Mg+Fe) ratio above 0.77, and are aluminum rich and plot to the right of the povondraite-oxidravite join, above the schorl-dravite join. Inherited tourmalines plot within the alkaline (Na+K) group field, and have a Mg/(Mg+Fe) ratio below 0.77. These data suggest that authigenic tourmalines grew under reducing conditions, compatible with the hydrothermal event responsible for the ore deposition and caprock formation during the diapir ascent
Pessimistic Fallibilism and Cognitive Vulnerability
In this text, the relationship between fallibilism and cognitive vulnerability is examined using Richard Rorty’s thinking as an example. First, some of Rorty’s central ideas are collected and commented on, especially the substitution of objectivity for solidarity, since it affects relevant issues of epistemology and of reflection on rationality. Next, the notions of fallibilism and cognitive vulnerability are examined, which will be connected to an existential dimension of vulnerability. Examples of all those things are also given from Rorty’s thinking and it is highlighted that the author operates with both a negative and a positive sense of existential vulnerability. It is then stated that Rorty’s proposal implies pessimistic fallibilism and an excess of cognitive vulnerability. First, it is argued that the cause of this lies in the fact that his approach is imprisoned in what Richard Bernstein called Cartesian anxiety and secondly, this generates unwanted consequences for the Rortyan goals themselves to raise his ethnocentric proposal as a non-relativistic alternative to realism and authoritarianism. In this respect, it is maintained that the priority that Rorty attributes to solidarity is accompanied by the rejection of any notion of evidence. This produces a conceptual lacuna in the structure of his thought that makes it impossible to reflect philosophically on an epistemic activity (the activity of adducing or requesting evidence) that is a normal part of day-to-day conversational exchanges as important as controversies to determine the best option in each case. In response, we will argue that one can better work towards the achievement of Rortyan goals if we bear in mind that reasons based on solidarity do not replace and do not deactivate the value of epistemic reasons, although they do combine and reinforce each other
The construction of the concept of citizenship in modernity
Se reflexiona aquí sobre las dificultades que la corriente mayoritaria del pensamiento dela modernidad encontró para engarzar en un paradigma igualitario y universal un conceptorestrictivo y elitista de ciudadanía. Esta posición se contrasta con los argumentos y críticas dela corriente minoritaria, defensora de un concepto universal y plural de ciudadania. Los aspectosontológicos de las diversas nociones ofrecidas de razón y naturaleza constituyen el eje argumentalde las tesis políticas de ambas corrientes. La incoherente solución ofrecida por la corrientemayoritaria supone mantener un concepto premoderno de sujeto, cuyo referente son las mujeres,junto al concepto moderno que alude (al menos virtualmente) a todos los varones.The focus of this paper are the problems that Modernity's mainstream thought encounteredwhen it attempted to fit an elitist and narrow concept of citizenship into an equalitarian anduniversal paradigm. This attitude opposes the arguments and criticism of the minoritarian stancewhich defends an universal and plural concept of citizenship. At the basis of both stances politicaltheses are the ontological aspects of the various concepts of reason and nature. The incoherentsolution posed by the majoritarian stance implies keeping a pre-modern concept of the subjectwhose reference are women, together with the modern concept which (at least virtually) refersto all men
La política como resistencia, la vulnerabilidad y algunos cabos sueltos
Butlerian notion of politics as resistance stands out for its originality, as it includes performativity and, at the same time, an openness to alliances. In this text I will argued that its singularity comes from the materialistic theoretical framework elaborated by Butler, since she portrays human beings as being socially tied by their mutual dependence and vulnerability. Finally, I will comment on three confused or problematic aspects of Butler’s proposal: the first related to reconciliation, the second with emancipation and the third with universality.La noción butleriana de política como resistencia destaca por su originalidad, pues se dobla de performatividad y, al mismo tiempo, está abierta a las alianzas. En este texto se argumenta que su singularidad proviene del marco teórico materialista elaborado por Butler, pues ofrece una caracterización de los seres humanos que los vincula socialmente por su mutua dependencia y vulnerabilidad. Finalmente, comentaré tres aspectos confusos o problemáticos de la propuesta butleriana: el primero relacionado con la reconciliación, el segundo con la emancipación y el tercero con la universalidad
Una herramienta para pensar nuestro tiempo
Pocas dudas hay hoy en día sobre la importancia de contar con buenas traducciones y ediciones de textos filosóficos relevantes. Más si se trata de textos clásicos, y más aún cuando las propuestas filosóficas que contienen no manifiestan el punto de vista hegemónico sobre el tema en cuestión. Estas son, precisamente, las circunstancias que acompañan a la reciente traducción al español realizada por Ángel Manuel Faerna de Lógica: La Teoría de la Investigación de John Dewey. No es la primera tra..
Modeling macroroughness contribution to fish habitat-suitability curves
Improved water management strategies necessitate a solid understanding of environmental impacts associated with various flow release policies. Habitat suitability models use hydrodynamic simulations to generate weighted usable area curves, which are useful in characterizing the ecological suitability of flow release rules. However, these models are not conveniently run to resolve the hydrodynamics at the smaller scales associated with macroroughness elements (e.g., individual stones), which produce wakes that contribute significantly to habitat suitability by serving as shelter zones where fishes can rest and feed. In this study, we propose a robust environmental indicator that considers the habitat generated by the wakes downstream of stones and can thus be used to assess the environmental efficiency of flow release rules for impounded streams. We develop an analytical solution to approximate the wake areas behind macroroughness elements, and the statistical distribution of wake areas is then found using the derived distribution approach. To illustrate the concept, we apply our theory to four exemplary river streams with dispersed stones having different statistical diameter size distributions, some of which allow for an analytical expression of the weighted usable area. We additionally investigate the impact of spatiotemporal changes in stone size distributions on the usable area and the consequent threshold flows. Finally, we include the proposed environmental indicator to solve a multiobjective reservoir optimization problem. This exemplifies its practical use and allows stakeholders to find the most favorable operational rules depending on the macroroughness characteristics of the impounded stream
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