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Adult basic education : a comparative survey of Massachusetts public school superintendents and adult education administrators.
Creep motion of a model frictional system
We report on the dynamics of a model frictional system submitted to minute
external perturbations. The system consists of a chain of sliders connected
through elastic springs that rest on an incline. By introducing cyclic
expansions and contractions of the springs we observe a reptation of the chain.
We account for the average reptation velocity theoretically. The velocity of
small systems exhibits a series of plateaus as a function of the incline angle.
Due to elastic e ects, there exists a critical amplitude below which the
reptation is expected to cease. However, rather than a full stop of the creep,
we observe in numerical simulations a transition between a continuous-creep and
an irregular-creep regime when the critical amplitude is approached. The latter
transition is reminiscent of the transition between the continuous and the
irregular compaction of granular matter submitted to periodic temperature
changes
Effects of NHC-Backbone Substitution on Efficiency in Ruthenium-Based Olefin Metathesis
series of ruthenium olefin metathesis catalysts bearing N-heterocyclic carbene (NHC) ligands with varying degrees of backbone and N-aryl substitution have been prepared. These complexes show greater resistance to decomposition through C−H activation of the N-aryl group, resulting in increased catalyst lifetimes. This work has utilized robotic technology to examine the activity and stability of each catalyst in metathesis, providing insights into the relationship between ligand architecture and enhanced efficiency. The development of this robotic methodology has also shown that, under optimized conditions, catalyst loadings as low as 25 ppm can lead to 100% conversion in the ring-closing metathesis of diethyl diallylmalonate
On Integral Class field theory for varieties over -adic fields
Let be a finite extension of the -adic numbers with ring
of integers , a regular scheme, proper, flat, and
geometrically irreducible over of dimension , and its generic fiber. We show, under some assumptions on , that
there is a reciprocity isomorphism of locally compact groups
from a new cohomology theory to an integral model of the abelianized geometric fundamental groups . After removing the contribution from the base field, the map
becomes an isomorphism of finitely generated abelian groups
Realizing students’ every day realities: Community analysis as a model for social justice
This article examines the implications and effect of the Community Analysis (CA) Project assignment that we utilize in the Multicultural Education (MCE) course1 at New Mexico State University, located in Las Cruces, New Mexico. The CA enables pre-service teachers to critically examine, through a social justice lens, the manifestations and intersectionalities of race, class, gender, sexual orientation, language, ability, and religion in PreK-12 students’ communities, which may be rejected and ignored, or embraced, serving to connect students’ lives to learning contexts and opportunities in their schools. The CA compels pre-service teachers to analyze systemic inequities and inequalities in communities which impact the everyday lives of students. They discover organic knowledge possessed by students and families to bridge students’ knowledge and the knowledge promoted within the school curriculum. Pre-service teachers also contemplate how their privileged or disadvantaged identity statuses intersect with their future students’ privileged or disadvantaged statuses, or impact how they read communities
Gemini Planet Imager Observational Calibrations III: Empirical Measurement Methods and Applications of High-Resolution Microlens PSFs
The newly commissioned Gemini Planet Imager (GPI) combines extreme adaptive
optics, an advanced coronagraph, precision wavefront control and a
lenslet-based integral field spectrograph (IFS) to measure the spectra of young
extrasolar giant planets between 0.9-2.5 um. Each GPI detector image, when in
spectral model, consists of ~37,000 microspectra which are under or critically
sampled in the spatial direction. This paper demonstrates how to obtain
high-resolution microlens PSFs and discusses their use in enhancing the
wavelength calibration, flexure compensation and spectral extraction. This
method is generally applicable to any lenslet-based integral field spectrograph
including proposed future instrument concepts for space missions.Comment: 10 pages, 6 figures. Proceedings of the SPIE, 9147-282 v2: reference
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Fluctuations of the Casimir-like force between two membrane inclusions
Although Casimir forces are inseparable from their fluctuations, little is
known about these fluctuations in soft matter systems. We use the membrane
stress tensor to study the fluctuations of the membrane-mediated Casimir-like
force. This method enables us to recover the Casimir force between two
inclusions and to calculate its variance. We show that the Casimir force is
dominated by its fluctuations. Furthermore, when the distance d between the
inclusions is decreased from infinity, the variance of the Casimir force
decreases as -1/d^2. This distance dependence shares a common physical origin
with the Casimir force itself.Comment: 5 pages, 3 figure
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