19,634 research outputs found
Social Conformity Despite Individual Preferences for Distinctiveness
We demonstrate that individual behaviors directed at the attainment of
distinctiveness can in fact produce complete social conformity. We thus offer
an unexpected generative mechanism for this central social phenomenon.
Specifically, we establish that agents who have fixed needs to be distinct and
adapt their positions to achieve distinctiveness goals, can nevertheless
self-organize to a limiting state of absolute conformity. This seemingly
paradoxical result is deduced formally from a small number of natural
assumptions, and is then explored at length computationally. Interesting
departures from this conformity equilibrium are also possible, including
divergence in positions. The effect of extremist minorities on these dynamics
is discussed. A simple extension is then introduced, which allows the model to
generate and maintain social diversity, including multimodal distinctiveness
distributions. The paper contributes formal definitions, analytical deductions,
and counterintuitive findings to the literature on individual distinctiveness
and social conformity.Comment: 11 pages, 6 figures, appendi
Effects of Aprons on Pitfall Trap Catches of Carabid Beetles in Forests and Fields
This study compared the efficacy of three types of pitfall traps in four forest and two field habitats. Two traps had aprons and one did not. The two apron traps were the same except for a gap between the trap and the plywood-apron, allowing captures from above or below. Traps were placed in a split-plot design and had three replicates of the three trap types per habitat. The traps were emptied each week from May to September. ANOVA\u27s were performed on 12 trapped species separately over habitats, weeks, and the in- teractions between them. The nonapron trap captured over 40% more individuals than either apron trap, though apron traps tended to be more effective in fields for species found in both habitats. Habitat-trap interactions were only significant in two species. Trap-week interactions were significant in four species
Effect of prolonged space flight on cardiac function and dimensions
Echocardiographic studies were performed preflight 5 days before launch and on recovery day and 1, 2, 4, 11, 31 and 68 days postflight. From these echocardiograms measurements were made. From these primary measurements, left ventricular end-diastolic volume, end-systolic volume, stroke volume, and mass were derived using the accepted assumptions. Findings in the Scientist Pilot and Pilot resemble those seen in trained distance runners. Wall thickness measurements were normal in all three crewmembers preflight. Postflight basal studies were unchanged in the Commander on recovery day through 68 days postflight in both the Scientist Pilot and Pilot, however, the left ventricular end-diastolic volume, stroke volume, and mass were decreased slightly. Left ventricular function curves were constructed for the Commander and Pilot by plotting stroke volume versus end-diastolic volume. In both astronauts, preflight and postflight data fell on the same straight line demonstrating that no deterioration in cardiac function had occurred. These data indicate that the cardiovascular system adapts well to prolonged weightlessness and suggest that alterations in cardiac dimensions and function are unlikely to limit man's future in space
Instability and spatiotemporal rheochaos in a shear-thickening fluid model
We model a shear-thickening fluid that combines a tendency to form
inhomogeneous, shear-banded flows with a slow relaxational dynamics for fluid
microstructure. The interplay between these factors gives rich dynamics, with
periodic regimes (oscillating bands, travelling bands, and more complex
oscillations) and spatiotemporal rheochaos. These phenomena, arising from
constitutive nonlinearity not inertia, can occur even when the steady-state
flow curve is monotonic. Our model also shows rheochaos in a low-dimensional
truncation where sharply defined shear bands cannot form
Explicit Zeta Functions for Bosonic and Fermionic Fields on a Noncommutative Toroidal Spacetime
Explicit formulas for the zeta functions corresponding to
bosonic () and to fermionic () quantum fields living on a
noncommutative, partially toroidal spacetime are derived. Formulas for the most
general case of the zeta function associated to a quadratic+linear+constant
form (in {\bf Z}) are obtained. They provide the analytical continuation of the
zeta functions in question to the whole complex plane, in terms of series
of Bessel functions (of fast, exponential convergence), thus being extended
Chowla-Selberg formulas. As well known, this is the most convenient expression
that can be found for the analytical continuation of a zeta function, in
particular, the residua of the poles and their finite parts are explicitly
given there. An important novelty is the fact that simple poles show up at
, as well as in other places (simple or double, depending on the number of
compactified, noncompactified, and noncommutative dimensions of the spacetime),
where they had never appeared before. This poses a challenge to the
zeta-function regularization procedure.Comment: 15 pages, no figures, LaTeX fil
Fiscal federalism vs fiscal decentralization in healthcare: a conceptual framework
INTRODUCTION: Fiscal federalism and fiscal decentralization are distinct policy options in public services in general and healthcare in particular, with possibly opposed effects on equity, effectiveness, and efficiency. However, the pertinent discourse often reflects confusion between the concepts or conflation thereof. METHODS: This paper performs a narrative review of theoretical literature on decentralization. The study offers clear definitions of the concepts of fiscal federalism and fiscal decentralization and provides an overview of the potential implications of each policy for healthcare systems. RESULTS: The interpretation of the literature identified three different dimensions of decentralization: political, administrative, economic. Economic decentralization can be further implemented through two different policy options: fiscal federalism and fiscal decentralization. Fiscal federalism is the transfer of spending authority of a centrally pooled public health budget to local governments or authorities. Countries like the UK, Cuba, Denmark, and Brazil mostly rely on fiscal federalism mechanisms for healthcare financing. Fiscal decentralization consists of transferring both pooling and spending responsibilities from the central government to local authorities. Contrarily to fiscal federalism, the implementation of fiscal decentralization requires as a precondition the fragmentation of the national pool into many local pools. The restructuring of the pooling system may limit the cross-subsidization effect between high- and low-income groups and areas that a central pool guarantees; thus, severely affecting local equality and equity. With the limited availability of local public resources in poorer regions, the quality of services drops, increasing the disparity gap between areas. Evidence from Italy, Spain, China, and Ivory Coast -countries with a strong fiscal decentralization element in their healthcare services- suggests that fiscal decentralization has positive effects on the infant mortality rate. However, it decreases healthcare resources as well as access to services, fostering spatial inequities. CONCLUSION: If public resources are and remain adequate, allocation follows equitable criteria, and local communities are involved in the decision-making debate, fiscal federalism -rather than fiscal decentralization- appear to be an adequate policy option to improve the healthcare services and population's health nationwide and achieve health sector economic decentralization. HIPPOKRATIA 2020, 24(3): 107-113
Expanding direction of the period doubling operator
We prove that the period doubling operator has an expanding direction at the
fixed point. We use the induced operator, a ``Perron-Frobenius type operator'',
to study the linearization of the period doubling operator at its fixed point.
We then use a sequence of linear operators with finite ranks to study this
induced operator. The proof is constructive. One can calculate the expanding
direction and the rate of expansion of the period doubling operator at the
fixed point
Causal perturbation theory in terms of retarded products, and a proof of the Action Ward Identity
In the framework of perturbative algebraic quantum field theory a local
construction of interacting fields in terms of retarded products is performed,
based on earlier work of Steinmann. In our formalism the entries of the
retarded products are local functionals of the off shell classical fields, and
we prove that the interacting fields depend only on the action and not on terms
in the Lagrangian which are total derivatives, thus providing a proof of
Stora's 'Action Ward Identity'. The theory depends on free parameters which
flow under the renormalization group. This flow can be derived in our local
framework independently of the infrared behavior, as was first established by
Hollands and Wald. We explicitly compute non-trivial examples for the
renormalization of the interaction and the field.Comment: 76 pages, to appear in Rev. Math. Phy
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