Convoy screening against a mixed submarine threat (U)

(U) The problem of convoy defense against a mixed threat of conventional and nuclear submarines is posed. A general, conceptual method of solution is offered from which a simple analytical model is constructed. Use of the model for obtaining optimal policies of screening force disposition is demonstrated. Underlying assumptions of the model and related tactical problem areas are discussed and analyzed.http://archive.org/details/convoyscreeningg109453040

LA EDUCACIÓN PARA UNA CIUDADANÍA PELIGROSA

El concepto de educación pública se encuentra bajo la influencia de las imágenes dominantes y dominadoras más que en la autentica comprensión de la complejidad de las realidades diarias del aula. Basándose en los trabajos de Debord y Foucault, especialmente en sus visiones libertarias y antiestáticas del poder, de la autoridad y del control en la sociedad contemporánea, este artículo examina cómo el control social se ejerce a través de las imágenes dominantes y una mezcla de vigilancia y espectáculo. En respuesta a estas condiciones, desarrollamos el concepto de «ciudadanía peligrosa». Reclamamos que las condiciones contemporáneas requieren de una Educación para la Ciudadanía antiopresiva, que se tome en serio las desigualdades sociales y económicas, y la opresión fruto del capitalismo neoliberal que restringe las posibilidades antiopresivas y establece unas pedagogías oficiales y sancionadoras. El poder pedagógico de la ciudadanía peligrosa reside: 1) en la capacidad de alentar al alumnado y al profesorado sobre las implicaciones de su propia enseñanza y aprendizaje; 2) en visualizar una educación focalizada en la libertad y en la democracia, y 3) en interrogar y deconstruir sus bienintencionadas complicidades con el sistema a partir de prácticas y textos culturales, especialmente para relacionar las condiciones opresivas con las prácticas culturales del mismo estilo, y viceversaConceptualizations of public schooling rest upon the influence of dominant and dominating images rather than on more authentic understandings of the complex realities of classroom life. Drawing upon the work of both Debord and Foucault, particularly their libertarian and anti-statist visions of power, authority, and control in contemporary society, this article examines how social control is exercised via controlling images and a merger of surveillance and spectacle. In response to these conditions we develop the concept of “dangerous citizenship.” We argue that contemporary conditions demand an antioppressive citizenship education, one that takes seriously social and economic inequalities and oppression that result from neoliberal capitalism and that builds upon the antioppressive possibilities of established and offi cially sanctioned pedagogies. The pedagogical power dangerous citizenship resides in its capacity to encourage students and educators to challenge the implications of their own education/instruction, to envision an education that is free and democratic to the core, and to interrogate and uncover their own well-intentioned complicity in the conditions within which various cultural texts and practices appear, especially to the extent that oppressive conditions create oppressive cultural practices, and vicevers

Humanización de la Pedagogía Crítica ¿Qué clase de profesores? ¿Qué clase de ciudadanía? ¿Qué clase de futuro? / Humanizing critical pedagogy: What kind of teachers? What kind of citizenship? What kind of future?

La pedagogía crítica es entendida (y malentendida) en muchos sentidos. Generalmente, asociada con Paulo Freire (1970) en su oposición al método bancario de la educación, también está muy asociada a los análisis neomarxistas basados en la teoría crítica de la educación, la escolarización y la sociedad. A pesar de las percepciones y las conceptualizaciones difundidas de la pedagogía crítica, por parte de sus más reconocidos autores, no hay una perspectiva ideológica única o un movimiento social, que defina a la pedagogía crítica. Las conceptualizaciones dominantes sobre la pedagogía crítica son innecesariamente limitadas, tanto política como filosóficamente. Como resultado, este enfoque pedagógico de poder innegable ha sido socavado y su impacto mellado. La pedagogía crítica se ha convertido más en una serie de creencias a priori sobre el mundo presentadas como mapas a seguir que un proceso por el cual losestudiantes investigan el mundo y construyen comprensiones personales y significativas que les ayudan en la lucha para superar la opresión y lograr la libertad. En otras palabras, la pedagogía crítica ha encontrado el enemigo, somos nosotros, o al menos nos incluye. Si la pedagogía crítica, como proceso educativo, pretende lograr sus objetivos, no puede exceptuarse a si misma del desarraigo y el examen de sus propios supuestos subyacentes, pronunciamientos, clichés y conocimientos alcanzados. Mi objetivo aquí es ampliar la concepción acerca de la pedagogía crítica, mientras se mantienen sus características definitorias, que la convierten en una práctica educativa distinta a los abordajes tradicionales. Ejemplificaré cómo podríamos hacer de la pedagogía crítica una práctica cada vez más adoptada por el profesorado y adelantaré las consecuencias sobre los individuos. escuelas y sociedad si se optara por una concepción menos ortodoxa de lo que significa practicar la pedagogía crítica

Educación en estudios sociales y reforma de la educación basada en estándares en Norte América: Estandarización del currículo, pruebas de alta exigencia y resistencia.

Social studies have a contentious history as a school subject and this article begins with an overview of the historically competing viewpoints on the nature and purposes of social studies education in the North American context. Next, we provide a critical examination of recent educational reforms in the USA (No Child Left Behind and Common Core State Standards), which use high-stakes testing as a tool for standardizing the social studies curriculum and teaching methods. The final section of the article examines both the significant levels of resistance to high-stakes testing and curriculum standardization by students, teachers, and the public and the question of whether social studies education will promote citizenship that is adaptive to the status quo or the reconstruction society in more equitable and socially just ways

The global distribution of Bacillus anthracis and associated anthrax risk to humans, livestock and wildlife.

Bacillus anthracis is a spore-forming, Gram-positive bacterium responsible for anthrax, an acute infection that most significantly affects grazing livestock and wild ungulates, but also poses a threat to human health. The geographic extent of B. anthracis is poorly understood, despite multi-decade research on anthrax epizootic and epidemic dynamics; many countries have limited or inadequate surveillance systems, even within known endemic regions. Here, we compile a global occurrence dataset of human, livestock and wildlife anthrax outbreaks. With these records, we use boosted regression trees to produce a map of the global distribution of B. anthracis as a proxy for anthrax risk. We estimate that 1.83 billion people (95% credible interval (CI): 0.59-4.16 billion) live within regions of anthrax risk, but most of that population faces little occupational exposure. More informatively, a global total of 63.8 million poor livestock keepers (95% CI: 17.5-168.6 million) and 1.1 billion livestock (95% CI: 0.4-2.3 billion) live within vulnerable regions. Human and livestock vulnerability are both concentrated in rural rainfed systems throughout arid and temperate land across Eurasia, Africa and North America. We conclude by mapping where anthrax risk could disrupt sensitive conservation efforts for wild ungulates that coincide with anthrax-prone landscapes

Mojave Applied Ecology Notes Summer 2011

Thoughts on fire possibilities on Mount Charleston, estimating historical densities of Ponderosa pine in northern AZ, over-understory changes in the Spring Mountains, seeding effectiveness in Red Rock Canyon, workshop announcements

The role of electronic symmetry in charge-transfer-to-solvent reactions: Quantum nonadiabatic computer simulation of photoexcited sodium anions

Since charge-transfer-to-solvent (CTTS) reactions represent the simplest class of solvent-driven electron transfer reactions, there has been considerable interest in understanding the solvent motions responsible for electron ejection. The major question that we explore in this paper is what role the symmetry of the electronic states plays in determining the solvent motions that account for CTTS. To this end, we have performed a series of one-electron mixed quantum/classical nonadiabatic molecular dynamics simulations of the CTTS dynamics of sodide, Na-, which has its ground-state electron in an s orbital and solvent-supported CTTS excited states of p-like symmetry. We compare our simulations to previous theoretical work on the CTTS dynamics of the aqueous halides, in which the ground state has the electron in a p orbital and the CTTS excited state has s-like symmetry. We find that the key motions for Na- relaxation involve translations of solvent molecules into the node of the p-like CTTS excited state. This solvation of the electronic node leads to migration of the excited CTTS electron, leaving one of the p-like lobes pinned to the sodium atom core and the other extended into the solvent; this nodal migration causes a breakdown of linear response. Most importantly, for the nonadiabatic transition out of the CTTS excited state and the subsequent return to equilibrium, we find dramatic differences between the relaxation dynamics of sodide and the halides that result directly from differences in electronic symmetry. Since the ground state of the ejected electron is s-like, detachment from the s-like CTTS excited state of the halides occurs directly, but detachment cannot occur from the p-like CTTS excited state of Na- without a nonadiabatic transition to remove the node. Thus, unlike the halides, CTTS electron detachment from sodide occurs only after relaxation to the ground state and is a relatively rare event. In addition, the fact that the electronic symmetry of sodide is the same as for the hydrated electron enables us to directly study the effect of a stabilizing atomic core on the properties and solvation dynamics of solvent-supported electronic states. All the results are compared to experimental work on Na- CTTS dynamics, and a unified picture for the electronic relaxation for solvent-supported excited states of any symmetry is presented. (C) 2003 American Institute of Physics

Historical Mammal Extinction on Christmas Island (Indian Ocean) Correlates with Introduced Infectious Disease

It is now widely accepted that novel infectious disease can be a leading cause of serious population decline and even outright extinction in some invertebrate and vertebrate groups (e.g., amphibians). In the case of mammals, however, there are still no well-corroborated instances of such diseases having caused or significantly contributed to the complete collapse of species. A case in point is the extinction of the endemic Christmas Island rat (Rattus macleari): although it has been argued that its disappearance ca. AD 1900 may have been partly or wholly caused by a pathogenic trypanosome carried by fleas hosted on recently-introduced black rats (Rattus rattus), no decisive evidence for this scenario has ever been adduced. Using ancient DNA methods on samples from museum specimens of these rodents collected during the extinction window (AD 1888–1908), we were able to resolve unambiguously sequence evidence of murid trypanosomes in both endemic and invasive rats. Importantly, endemic rats collected prior to the introduction of black rats were devoid of trypanosome signal. Hybridization between endemic and black rats was also previously hypothesized, but we found no evidence of this in examined specimens, and conclude that hybridization cannot account for the disappearance of the endemic species. This is the first molecular evidence for a pathogen emerging in a naïve mammal species immediately prior to its final collapse

Galaxy Zoo and SPARCFIRE: constraints on spiral arm formation mechanisms from spiral arm number and pitch angles

In this paper, we study the morphological properties of spiral galaxies, including measurements of spiral arm number and pitch angle. Using Galaxy Zoo 2, a stellar mass-complete sample of 6222 SDSS spiral galaxies is selected. We use the machine vision algorithm sparcfire to identify spiral arm features and measure their associated geometries. A support vector machine classifier is employed to identify reliable spiral features, with which we are able to estimate pitch angles for half of our sample. We use these machine measurements to calibrate visual estimates of arm tightness, and hence estimate pitch angles for our entire sample. The properties of spiral arms are compared with respect to various galaxy properties. The star formation properties of galaxies vary significantly with arm number, but not pitch angle. We find that galaxies hosting strong bars have spiral arms substantially (4°-6°) looser than unbarred galaxies. Accounting for this, spiral arms associated with many-armed structures are looser (by 2°) than those in two-armed galaxies. In contrast to this average trend, galaxies with greater bulge-to-total stellar mass ratios display both fewer and looser spiral arms. This effect is primarily driven by the galaxy disc, such that galaxies with more massive discs contain more spiral arms with tighter pitch angles. This implies that galaxy central mass concentration is not the dominant cause of pitch angle and arm number variations between galaxies, which in turn suggests that not all spiral arms are governed by classical density waves or modal theories