8,829 research outputs found
A study of the probability of depositing viable organisms on Mars during the Mariner 1964 mission
Probability of depositing viable organisms on Mars during 1964 Mariner missio
The Language and Logic of Law: A Case Study
Law is a social practice that consists of argument, in large part. This article is a case study of legal argument. The author has undertaken the study in the belief that the forms assumed by legal argument relate to lawyers\u27 conscious or unconscious understanding about what is persuasive in a given legal context. One can articulate these understandings by identifying and describing particular forms of argument and by determining the circumstances in which lawyers use each form. The author examines a set of Supreme Court opinions, using as a guide one of the few contemporary attempts to organize and classify forms of argument
Supramolecular Coordination Complexes as Optical Biosensors
In recent years, luminescent supramolecular coordination complexes (SCCs), including 2D-metallacycles and 3D-metallacages have been utilised for biomolecular analysis. Unlike small-molecular probes, the dimensions, size, shape, and flexibility of these complexes can easily be tuned by combining ligands designed with particular geometries, symmetries and denticity with metal ions with strong geometrical binding preferences. The well-defined cavities that result, in combination with the other non-covalent interactions that can be programmed into the ligand design, facilitate great selectivity towards guest binding. In this Review we will discuss the application of luminescent metallacycles and cages in the binding and detection of a wide range of biomolecules, such as carbohydrates, proteins, amino acids, and biogenic amines. We aim to explore the effect of the structural diversity of SCCs on the extent of biomolecular sensing, expressed in terms of sensitivity, selectivity and detection range
Rotorcraft contingency power study
Twin helicopter engines are often sized by the power requirement of a safe mission completion after the failure of one of the two engines. This study was undertaken for NASA Lewis by General Electric Co. to evaluate the merits of special design features to provide a 2-1/2 Contingency Power rating, permitting an engine size reduction. The merits of water injection, turbine cooling airflow modulation, throttle push, and a propellant auxiliary power plant were evaluated using military Life Cycle Cost (LCC) and commercial helicopter Direct Operating Cost (DOC) merit factors in a rubber engine and a rubber aircraft scenario
Experimental determination of the state-dependent enhancement of the electron-positron momentum density in solids
The state-dependence of the enhancement of the electron-positron momentum
density is investigated for some transition and simple metals (Cr, V, Ag and
Al). Quantitative comparison with linearized muffin-tin orbital calculations of
the corresponding quantity in the first Brillouin zone is shown to yield a
measurement of the enhancement of the s, p and d states, independent of any
parameterizations in terms of the electron density local to the positron. An
empirical correction that can be applied to a first-principles state-dependent
model is proposed that reproduces the measured state-dependence very well,
yielding a general, predictive model for the enhancement of the momentum
distribution of positron annihilation measurements, including those of angular
correlation and coincidence Doppler broadening techniques
Galaxy Peculiar Velocities and Infall onto Groups
We perform statistical analyses to study the infall of galaxies onto groups
and clusters in the nearby Universe. The study is based on the UZC and SSRS2
group catalogs and peculiar velocity samples. We find a clear signature of
infall of galaxies onto groups over a wide range of scales 5 h^{-1} Mpc<r<30
h^{-1} Mpc, with an infall amplitude on the order of a few hundred kilometers
per second. We obtain a significant increase in the infall amplitude with group
virial mass (M_{V}) and luminosity of group member galaxies (L_{g}). Groups
with M_{V}<10^{13} M_{\odot} show infall velocities V_{infall} \simeq 150 km
s^{-1} whereas for M_{V}>10^{13} M_{\odot} a larger infall is observed,
V_{infall} \simeq 200 km s^{-1}. Similarly, we find that galaxies surrounding
groups with L_{g}<10^{15} L_{\odot} have V_{infall} \simeq 100 km s^{-1},
whereas for L_{g}>10^{15} L_{\odot} groups, the amplitude of the galaxy infall
can be as large as V_{infall} \simeq 250 km s^{-1}. The observational results
are compared with the results obtained from mock group and galaxy samples
constructed from numerical simulations, which include galaxy formation through
semianalytical models. We obtain a general agreement between the results from
the mock catalogs and the observations. The infall of galaxies onto groups is
suitably reproduced in the simulations and, as in the observations, larger
virial mass and luminosity groups exhibit the largest galaxy infall amplitudes.
We derive estimates of the integrated mass overdensities associated with groups
by applying linear theory to the infall velocities after correcting for the
effects of distance uncertainties obtained using the mock catalogs. The
resulting overdensities are consistent with a power law with \delta \sim 1 at r
\sim 10 h^{-1}Mpc.Comment: 25 pages, 10 figure
Transport and diffusion in the embedding map
We study the transport properties of passive inertial particles in a
incompressible flows. Here the particle dynamics is represented by the
dissipative embedding map of area-preserving standard map which models
the incompressible flow. The system is a model for impurity dynamics in a fluid
and is characterized by two parameters, the inertia parameter , and the
dissipation parameter . We obtain the statistical characterisers of
transport for this system in these dynamical regimes. These are, the recurrence
time statistics, the diffusion constant, and the distribution of jump lengths.
The recurrence time distribution shows a power law tail in the dynamical
regimes where there is preferential concentration of particles in sticky
regions of the phase space, and an exponential decay in mixing regimes. The
diffusion constant shows behaviour of three types - normal, subdiffusive and
superdiffusive, depending on the parameter regimes. Phase diagrams of the
system are constructed to differentiate different types of diffusion behaviour,
as well as the behaviour of the absolute drift. We correlate the dynamical
regimes seen for the system at different parameter values with the transport
properties observed at these regimes, and in the behaviour of the transients.
This system also shows the existence of a crisis and unstable dimension
variability at certain parameter values. The signature of the unstable
dimension variability is seen in the statistical characterisers of transport.
We discuss the implications of our results for realistic systems.Comment: 28 pages, 14 figures, To Appear in Phys. Rev. E; Vol. 79 (2009
Functional analysis in behavior therapy: behavioral foundations and clinical application
This theoretical study reviews the theoretical and applied foundations of
a functional analysis strategy in clinical case-formulation. Functional relations between
variables are those that demonstrate a mathematical association. Causal functional relations
between variables require: (a) covariance, (b) a logical connection, (c) temporal precedence
of the causal variable, and (d) absence of a third variable explaining the relation. There
are unidirectional, bidirectional, moderating, and mediating (i.e., explanatory) causal
functional relations. In a functional analysis the relevant, controllable, and causal functional
relations that apply to particular behaviors of an individual are identified. A functionalanalytic
approach to case-formulation is designed to minimize clinical judgment bias
and optimize clinical decision-making in the assessment and treatment processes.
Additional features of a functional analysis and its use for intervention design are
discussed within the context of a patient diagnosed with Schizophrenia Paranoid Type.
This article also considers the conditional nature and limitations of a functional-analytic
approach in clinical psychology.En este estudio teórico se revisan los fundamentos teóricos y aplicados de
un modelo de análisis funcional en formulación clínica de casos. Las relaciones funcionales
entre variables demuestran una asociación matemática; el subconjunto de relaciones
funcionales causales requiere además: (a) covarianza, (b) conexión lógica, (c)
precisión temporal de la variable causal y (d) exclusión de terceras variables que
expliquen la relación. Hay relaciones funcionales cuasales unidireccionales, bidireccionales,
moderadoras y mediadoras (explicativas). En el análisis funcional se identifican las
relaciones funcionales relevantes, controlables y causales que se asocian a determinados
comportamientos del individuo. Una aproximación analítico-funcional a la formulación
clínica de casos está concebida para minimizar los sesgos de juicio clínico y
optimizar la toma de decisiones durante los procesos de evaluación y tratamiento.
Aspectos adicionales del análisis funcional y de su uso para el diseño de intervenciones
se ilustran en el contexto de un caso diagnosticado de esquizofrenia tipo paranoide;
entre ellos, un modelo matemático sencillo para estimar la eficacia del tratamiento
basado en análisis funcional. Finalmente, consideramos las limitaciones en el contexto
clínico de la aproximación al análisis funcional propuesta.Neste estudo teórico revêem-se os fundamentos teóricos e aplicados de um
modelo da análise funcional em formulação clínica de casos. As relações funcionais
entre variáveis demonstram uma associação matemática; o subconjunto de relações
funcionais causais requer: (a) covariância, (b) conexão lógica, (c) precisão temporal da
variável causal e (d) exclusão de terceiras variáveis que expliquem a relação. Há relações
funcionais causais unidireccionais, bidireccionais, moderadoras e mediadoras (explicativas).
Na análise funcional identificam-se as relações funcionais relevantes, controláveis
e causais que se associam a determinados comportamentos do indivíduo. Uma aproximação
analítico-funcional à formulação clínica de casos está concebida para minimizar os viés
de juízo clínico e optimizar a tomada de decisões durante os processos de avaliação e
tratamento. Aspectos adicionais da análise funcional e do seu uso para o planeamento
de intervenções ilustram-se no contexto de um caso diagnosticado com esquizofrenia
tipo paranoide; entre eles, um modelo matemático sensível para estimar a eficácia do
tratamento baseado na análise funcional. Finalmente, consideramos as limitações no
contexto clínico da aproximação à análise funcional proposta.This article was composed during a scholarship at the Psychology Department of the University of Hawai’i at Manoa (October 2003-May 2004) granted by the Servicio Andaluz de Salud as part of a three-years
internship program (PIR) in the Complejo Hospitalario de Jaén (Jaén, Spain)
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