Home About us Contact
|
Home About us Contact | ||
|
|
||
Physical Entities (physical + entity)
Selected AbstractsIn search of simple structures in climate: simplifying EOFsINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 1 2006A. Hannachi Abstract Empirical orthogonal functions (EOFs) are widely used in climate research to identify dominant patterns of variability and to reduce the dimensionality of climate data. EOFs, however, can be difficult to interpret. Rotated empirical orthogonal functions (REOFs) have been proposed as more physical entities with simpler patterns than EOFs. This study presents a new approach for finding climate patterns with simple structures that overcomes the problems encountered with rotation. The method achieves simplicity of the patterns by using the main properties of EOFs and REOFs simultaneously. Orthogonal patterns that maximise variance subject to a constraint that induces a form of simplicity are found. The simplified empirical orthogonal function (SEOF) patterns, being more ,local', are constrained to have zero loadings outside the main centre of action. The method is applied to winter Northern Hemisphere (NH) monthly mean sea level pressure (SLP) reanalyses over the period 1948,2000. The ,simplified' leading patterns of variability are identified and compared to the leading patterns obtained from EOFs and REOFs. Copyright © 2005 Royal Meteorological Society. [source] Reasoning across ontologically distinct levels: Students' understandings of molecular geneticsJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 7 2007Ravit Golan Duncan Abstract In this article we apply a novel analytical framework to explore students' difficulties in understanding molecular genetics,a domain that is particularly challenging to learn. Our analytical framework posits that reasoning in molecular genetics entails mapping across ontologically distinct levels,an information level containing the genetic information, and a physical level containing hierarchically organized biophysical entities such as proteins, cells, tissues, etc. This mapping requires an understanding of what the genetic information specifies, and how the physical entities in the system mediate the effects of this information. We therefore examined, through interview and written assessments, 10th grade students' understandings of molecular genetics phenomena to uncover the conceptual obstacles involved in reasoning across these ontologically distinct levels. We found that students' described the genetic instructions as containing information about both the structure and function of biological entities across multiple organization levels; a view that is far less constrained than the scientific understandings of the genetic information. In addition, students were often unaware of the different functions of proteins, their relationship to genes, and the role proteins have in mediating the effects of the genetic information. Students' ideas about genes and proteins hindered their ability to reason across the ontologically distinct levels of genetic phenomena, and to provide causal mechanistic explanations of how the genetic information brings about effects of a physical nature. © 2007 Wiley Periodicals, Inc. J Res Sci Teach 44: 938,959, 2007 [source] The properties of the heterogeneous Shakhbazyan groups of galaxies in the SDSSMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2009D. Capozzi ABSTRACT We present a systematic study of the subsample of Shakhbazyan (SHK) groups covered by the Sloan Digital Sky Survey Data Release 5 (SDSS DR5). SHK groups probe an environment with characteristics which are intermediate between those of loose and very compact groups. Surprisingly, we found that several groups identifying algorithms, e.g. Berlind et al. and Tago et al., miss this type of structures. Using the SDSS DR5 spectroscopic data and the photometric redshifts derived in D'Abrusco et al., we identified possible group members in photometric redshift space and derived, for each group, several individual properties (richness, size, mean photometric redshift, fraction of red galaxies, etc.). We also combined pointed and stacked Rosat All Sky Survey (RASS) data to investigate the X-ray luminosities of these systems. Our study confirms that the majority of groups are physical entities with richness in the range 3,13 galaxies, and properties ranging between those of loose and compact groups. We confirm that SHK groups are richer in early-type galaxies than the surrounding environment and the field, as expected from the morphology,density relation and from the selection of groups of red galaxies. Furthermore, our work supports the existence of two subclasses of structures, the first one being formed by compact and isolated groups and the second formed by extended structures. We suggest that while the first class of objects dwells in less dense regions like the outer parts of clusters or the field, possibly sharing the properties of Hickson Compact Groups, the more extended structures represent a mixture of [core + halo] configurations and cores of rich clusters. X-ray luminosities for SHK groups are generally consistent with these results and with the expectations for the LX,,v relation, but also suggest the velocity dispersions reported in literature are underestimated for some of the richest systems. [source] John Donne, godly inscription, and permanency of self in Devotions upon Emergent OccasionsRENAISSANCE STUDIES, Issue 3 2010Matthew Horn I argue that throughout his career but especially during his sickness of 1623, Donne fears self annihilation in death. Examining critical views on Donne's concept of death and the self, I identify this as a fear of a temporal blackout of the self between the body's death and the final Resurrection. Donne believes that the self is the result of the combination of the body and the soul, and although the soul can survive the body's dissolution, the self cannot. In order to counter this fear of the self's temporal disappearance, Donne seeks to inscribe himself in his Devotions upon Emergent Occasions, assuming the posture of an anatomist to distance himself from his physical body to capture the observations of his body in a text using a corporeal register. Donne preserves this textual encoding of himself by addressing God as the main audience for the Devotions: when God reads the text, the content of the text (Donne's self) becomes archived in the eternally stable mind of God. Ultimately, Donne's authorship of the Devotions is his imitation of God's own activity. Donne sees God's nature, his ,core self', as a system of eternally preserved propositions, and God's activity in creation is an act of copious literary expression using an alphabet of physical things that are used not for their own endurance qua physical entities but for their ability to figurative reveal God's self, which stands beyond and above them. Donne imitates this nature and activity in his act of writing the Devotions. [source] Organizational sticking points on NK LandscapesCOMPLEXITY, Issue 5 2002Jan W. Rivkin Abstract Scholars studying human organizations have recently adopted the notion of fitness landscapes, a concept pioneered in the biological and physical sciences. Such scholars have generally assumed that organizations will migrate toward the local peaks of these landscapes, as biological and physical entities do. We use an agent-based simulation to show, to the contrary, that a hierarchical human organization may very well come to rest at a "sticking point" that is not a local peak on the fitness landscape of the overall organization. Three pervasive features of human organizations create the distinction between sticking points and local peaks: the delegation of choices to separate decision makers, interdependencies between the domains of those decision makers, and differences between local incentives and global incentives. Our results illustrate both that it is valuable to use tools developed to study one type of complex adaptive system in order to examine another type and that researchers must adapt the tools with care as they attempt to do so. © 2002 Wiley Periodicals, Inc. [source] Thomas Pynchon: Gravity's Rainbow.ORBIS LITERARUM, Issue 3 2009The Ideas of the Opposite Thomas Pynchon's highly complex novel deals with the personal and social difficulty of accepting a new worldview. Set at the end of World War II and in its aftermath, the protagonists find themselves at the crossroads between Newtonian mechanics, epitomized by the V2 rockets, and the foreshadowed atom bomb, which is based on the theory of relativity and quantum mechanics. The style of Gravity's Rainbow resembles the scene of a subatomic world: it is presented as an ever-changing kaleidoscope of characters, places, events and interactions, which are constantly redetermined in relation to each other in an unpredictable manner. Pynchon manages to create a unifying theme by making all the twists in the plot comprehensible as manifestations of the underlying attempt to reconstruct selfhood. In addition, he refers recurrently to the motif of light, both as a physical entity at the center of modern physics and as a literary symbol of classical stability. In the end, his main protagonist himself turns into a mysterious source of light. [source] Producing North and South: a political geography of hydro development in QuébecTHE CANADIAN GEOGRAPHER/LE GEOGRAPHE CANADIEN, Issue 2 2004Caroline Desbiens Since the 1970s, the tapping of James Bay's hydroelectric potential has been synonymous with the tapping of divergent national imaginaries for native and non-native people in Québec. Exploitation of natural resources in the region has activated different narratives of political identity for each community. I explore this evolving political context by examining how, for each group, water has emerged simultaneously as a physical entity possessing economic value and a social artefact supporting the consolidation of national boundaries. I do so by analysing three phases of changing relationships around resource management, namely: hydroelectric development on the La Grande river in the 1970s; the Cree opposition to Great Whale in the 1990s; and the recent agreement concerning a new relationship between the two parties. In each of these phases, nature has been both the symbolic and material tie that binds different national identities and materialises their boundaries. While these are not boundaries in the traditional geopolitical understanding of the term, the forging of an equitable framework of development in the region depends on the recognition of nature as a historical and political formation that answers to different sets of national preoccupations. Depuis les années 70, le développement hydroélectrique de la Baie James a favorisé l'expression de deux imaginaires nationaux dans la province, celui des autochtones en parallèle avec celui des non-autochtones. L'exploitation des ressources naturelles de la région a donné lieu à des récits identitaires propres à chaque communauté. J'explore les changements dynamiques de ce contexte politique en examinant comment, pour chacun de ces groupes, l'eau est à la fois une entité physique possédant une certaine valeur économique, ainsi qu'un objet social capable de consolider les frontières nationales de chaque peuple. L'analyse se fait à travers trois phases de gérance des ressources: la construction du Complexe La Grande dans les années 70; l'opposition des Cris au projet Grande Baleine dans les années 90; et la signature récente d'une nouvelle entente entre les deux parties. Dans chacune de ces phases, la nature a constitué un terrain à la fois symbolique et matériel consolidant des frontières nationales divergentes. Même s'il ne s'agit pas de frontières ,géopolitiques' au sens propre du terme, la création d'une structure de développement équitable dans la région exige que la nature soit perçue dans toute sa dimension historique et politique afin de dégager les différentes priorités nationales qui s'expriment en son nom. [source] | ||||||||||