196 research outputs found
¿Qué tienen las asociaciones de la sociedad civil que promueven la democracia?
El autor analiza las asociaciones de la sociedad civil y su efecto como fuerzas democratizantes, desde el punto de vista de metas, estructuras internas, nexos con otros organismos, diversidad y multiplicidad, asà como la distribución de los distintos tipos de asociaciones, y los patrones de cambio ante nuevos retos. Concluye afirmando que aunque las asociaciones no son una panacea para promover la democracia, aparentemente sà acompañan su crecimiento y forman parte de cualquier sistema moderno.The author analyzes associations in civil society and their effect as democratizing forces, from the point of view of goals, internal structures, links with other organisms, diversity and multiplicity, as well as and the distribution of the different kinds of associations, and the patterns of change before new challenges. He concludes that although associations are not a panacea to promote democracy, apparently they do accompany its growth and are part of any modern system
The Enhancon, Multimonopoles and Fuzzy Geometry
The presentation at Strings 2000 was intended to be in two main parts, but
there was only time for part one. However both parts appeared on the online
proceedings, and are also included in this document. The first part concerns an
exploration of the connection between the physics of the `enhancon' geometry
arising from wrapping N D6-branes on the K3 manifold in Type IIA string theory
and that of a charge N BPS multi-monopole. This also relates to the physics of
2+1 dimensional SU(N) gauge theory with eight supercharges. The main results
uncovered by this exploration are: a) better insight into the non-perturbative
geometry of the enhancon; b) the structure of the moduli space geometry, and
its characterisation in terms of generalisations of an Atiyah-Hitchin-like
manifold; c) the use of Nahm data to describe aspects of the geometry, showing
that the enhancon locus itself has a description as a fuzzy sphere. Part two
discusses the addition of extra D2-branes into the geometry. Two probe
computations show the difference between the geometry as seen by D2-branes and
that seen by wrapped D6-branes, and the accompanying gauge theory
interpretations are discussed.Comment: 10 pages. Two figures. LaTeX, IJMP style. Contribution to proceedings
of Strings 2000, held at Michigan
Gauge Theory and the Excision of Repulson Singularities
We study brane configurations that give rise to large-N gauge theories with
eight supersymmetries and no hypermultiplets. These configurations include a
variety of wrapped, fractional, and stretched branes or strings. The
corresponding spacetime geometries which we study have a distinct kind of
singularity known as a repulson. We find that this singularity is removed by a
distinctive mechanism, leaving a smooth geometry with a core having an enhanced
gauge symmetry. The spacetime geometry can be related to large-N Seiberg-Witten
theory.Comment: 31 pages LaTeX, 2 figures (v3: references added
The Final Fate of the Rolling Tachyon
We propose an alternative interpretation of the boundary state for the
rolling tachyon, which may depict the time evolution of unstable D-branes in
string theory. Splitting the string variable in the temporal direction into the
classical part, which we may call "time" and the quantum one, we observe the
time dependent behaviour of the boundary. Using the fermion representation of
the rolling tachyon boundary state, we show that the boundary state correctly
describes the time-dependent decay process of the unstable D-brane into a
S-brane at the classical level.Comment: 9 pages, revte
Ligand and Receptor Dynamics Contribute to the Mechanism of Graded PPARÎł Agonism
SummaryLigand binding to proteins is not a static process, but rather involves a number of complex dynamic transitions. A flexible ligand can change conformation upon binding its target. The conformation and dynamics of a protein can change to facilitate ligand binding. The conformation of the ligand, however, is generally presumed to have one primary binding mode, shifting the protein conformational ensemble from one state to another. We report solution nuclear magnetic resonance (NMR) studies that reveal peroxisome proliferator-activated receptor Îł (PPARÎł) modulators can sample multiple binding modes manifesting in multiple receptor conformations in slow conformational exchange. Our NMR, hydrogen/deuterium exchange and docking studies reveal that ligand-induced receptor stabilization and binding mode occupancy correlate with the graded agonist response of the ligand. Our results suggest that ligand and receptor dynamics affect the graded transcriptional output of PPARÎł modulators
Twistors, Harmonics and Holomorphic Chern-Simons
We show that the off-shell N=3 action of N=4 super Yang-Mills can be written
as a holomorphic Chern-Simons action whose Dolbeault operator is constructed
from a complex-real (CR) structure of harmonic space. We also show that the
local space-time operators can be written as a Penrose transform on the coset
SU(3)/(U(1) \times U(1)). We observe a strong similarity to ambitwistor space
constructions.Comment: 34 pages, 3 figures, v2: replaced with published version, v3: Added
referenc
Prime beef cuts : culinary images for thinking 'men'
The paper contributes to scholarship theorising the sociality of the brand in terms of subject positions it makes possible through drawing upon the generative context of circulating discourses, in this case of masculinity, cuisine and celebrity. Specifically, it discusses masculinity as a socially constructed gender practice (Bristor and Fischer, 1993), examining materialisations of such practice in the form of visualisations of social relations as resources for 'thinking gender' or 'doing gender'. The transformative potential of the visualisations is illuminated by exploring the narrative content choreographed within a series of photographic images positioning the market appeal of a celebrity chef through the medium of a contemporary lifestyle cookery book. We consider how images of men 'doing masculinity'are not only channelled into reproducing existing gender hierarchy and compulsory heterosexuality in the service of commercial ends, but also into disrupting such enduring stereotyping through subtle reframing. We acknowledge that masculinity is already inscribed within conventionalised representations of culinary culture. In this case we consider how traces of masculinity are exploited and reinscribed through contemporary images that generate resources for rethinking masculine roles and identities, especially when viewed through the lens of stereotypically feminised pursuits such as shopping, food preparation, cooking, and the communal intimacy of food sharing. We identify unsettling tensions within the compositions, arguing that they relate to discursive spaces between the gendered positions written into the images and the popular imagination they feed off. Set against landscapes of culinary culture, we argue that the images invoke a brand of naively roughish "laddishness" or "blokishness", rendering it in domesticated form not only as benign and containable, but fashionable, pliable and, importantly, desirable. We conclude that although the images draw on stereotypical premeditated notions of a feral, boisterous and untamed heterosexual masculinity, they also set in motion gender-blending narratives
Moduli Spaces of Instantons on the Taub-NUT Space
We present ADHM-Nahm data for instantons on the Taub-NUT space and encode
these data in terms of Bow Diagrams. We study the moduli spaces of the
instantons and present these spaces as finite hyperkahler quotients. As an
example, we find an explicit expression for the metric on the moduli space of
one SU(2) instanton. We motivate our construction by identifying a
corresponding string theory brane configuration. By following string theory
dualities we are led to supersymmetric gauge theories with impurities.Comment: 26 pages, 7 figure
Systematic reviews: a cross-sectional study of location and citation counts
BACKGROUND: Systematic reviews summarize all pertinent evidence on a defined health question. They help clinical scientists to direct their research and clinicians to keep updated. Our objective was to determine the extent to which systematic reviews are clustered in a large collection of clinical journals and whether review type (narrative or systematic) affects citation counts. METHODS: We used hand searches of 170 clinical journals in the fields of general internal medicine, primary medical care, nursing, and mental health to identify review articles (year 2000). We defined 'review' as any full text article that was bannered as a review, overview, or meta-analysis in the title or in a section heading, or that indicated in the text that the intention of the authors was to review or summarize the literature on a particular topic. We obtained citation counts for review articles in the five journals that published the most systematic reviews. RESULTS: 11% of the journals concentrated 80% of all systematic reviews. Impact factors were weakly correlated with the publication of systematic reviews (R(2 )= 0.075, P = 0.0035). There were more citations for systematic reviews (median 26.5, IQR 12 â 56.5) than for narrative reviews (8, 20, P <.0001 for the difference). Systematic reviews had twice as many citations as narrative reviews published in the same journal (95% confidence interval 1.5 â 2.7). CONCLUSIONS: A few clinical journals published most systematic reviews. Authors cited systematic reviews more often than narrative reviews, an indirect endorsement of the 'hierarchy of evidence'
Establishing a library of resources to help people understand key concepts in assessing treatment claimsâThe âCritical thinking and Appraisal Resource Libraryâ (CARL)
Background
People are frequently confronted with untrustworthy claims about the effects of treatments. Uncritical acceptance of these claims can lead to poor, and sometimes dangerous, treatment decisions, and wasted time and money. Resources to help people learn to think critically about treatment claims are scarce, and they are widely scattered. Furthermore, very few learning-resources have been assessed to see if they improve knowledge and behavior.
Objectives
Our objectives were to develop the Critical thinking and Appraisal Resource Library (CARL). This library was to be in the form of a database containing learning resources for those who are responsible for encouraging critical thinking about treatment claims, and was to be made available online. We wished to include resources for groups we identified as âintermediariesâ of knowledge, i.e. teachers of schoolchildren, undergraduates and graduates, for example those teaching evidence-based medicine, or those communicating treatment claims to the public. In selecting resources, we wished to draw particular attention to those resources that had been formally evaluated, for example, by the creators of the resource or independent research groups.
Methods
CARL was populated with learning-resources identified from a variety of sourcesâtwo previously developed but unmaintained inventories; systematic reviews of learning-interventions; online and database searches; and recommendations by members of the project group and its advisors. The learning-resources in CARL were organised by âKey Conceptsâ needed to judge the trustworthiness of treatment claims, and were made available online by the James Lind Initiative in Testing Treatments interactive (TTi) English (www.testingtreatments.org/category/learning-resources).TTi English also incorporated the database of Key Concepts and the Claim Evaluation Tools developed through the Informed Healthcare Choices (IHC) project (informedhealthchoices.org).
Results
We have created a database of resources called CARL, which currently contains over 500 open-access learning-resources in a variety of formats: text, audio, video, webpages, cartoons, and lesson materials. These are aimed primarily at âIntermediariesâ, that is, âteachersâ, âcommunicatorsâ, âadvisorsâ, âresearchersâ, as well as for independent âlearnersâ. The resources included in CARL are currently accessible at www.testingtreatments.org/category/learning-resources
Conclusions
We hope that ready access to CARL will help to promote the critical thinking about treatment claims, needed to help improve healthcare choices
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