1,884 research outputs found
What Does an Exemplary Middle School Mathematics Teacher Look Like? The Use of a Professional Development Rubric
A School University Research Network (SURN) committee composed of current mathematics teachers, central office math supervisors, building administrators, mathematicians, and mathematics educators researched numerous sources regarding best practices in mathematics instruction. The resulting professional development rubric synthesizes their findings and can serve a professional development role by providing teachers and administrators with a tool to develop clarity and consensus on best mathematics instructional practices, and how these practices are implemented in the classroom. It is also being used as a tool for cooperating teachers in their supervision of student teachers and as a reflective method for self-evaluation
VLBI Observations of Southern Gamma-Ray Sources. III
We report the results of Long Baseline Array observations made in 2001 of ten southern sources proposed by Mattox et al. as counterparts to EGRET > 100 MeV gamma-ray sources. Source structures are compared with published data where available and possible superluminal motions identified in several cases. The associations are examined in the light of Fermi observations, indicating that the confirmed counterparts tend to have radio properties consistent with other identifications, including flat radio spectral index, high brightness temperature, greater radio variability, and higher core dominance
Post-agrarian aspirations: tourism and rural politics in Ecuador
This ethnographic study examines post-agrarian aspirations and rural politics in Ecuador. After decades of urban outmigration under a neoliberal agrarian order, many rural places have witnessed efforts to develop local tourism economies as a possibility to transcend stigmatised agrarian livelihoods and to (re)constitute communities. We build on anthropological studies of aspiration to explore how visions of post-agrarian futures are shifting the actors, scales and terms of rural politics in the present. Through two case studies, we observe how state actors have come to re-inscribe their role within post-agrarian imaginaries, partially rewriting the terms of state legitimacy in rural places
Antisense Suppression of the Small Chloroplast Protein CP12 in Tobacco Alters Carbon Partitioning and Severely Restricts Growth
Abstract
The thioredoxin-regulated chloroplast protein CP12 forms a multienzyme complex with the Calvin-Benson cycle enzymes phosphoribulokinase (PRK) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). PRK and GAPDH are inactivated when present in this complex, a process shown in vitro to be dependent upon oxidized CP12. The importance of CP12 in vivo in higher plants, however, has not been investigated. Here, antisense suppression of CP12 in tobacco (Nicotiana tabacum) was observed to impact on NAD-induced PRK and GAPDH complex formation but had little effect on enzyme activity. Additionally, only minor changes in photosynthetic carbon fixation were observed. Despite this, antisense plants displayed changes in growth rates and morphology, including dwarfism and reduced apical dominance. The hypothesis that CP12 is essential to separate oxidative pentose phosphate pathway activity from Calvin-Benson cycle activity, as proposed in cyanobacteria, was tested. No evidence was found to support this role in tobacco. Evidence was seen, however, for a restriction to malate valve capacity, with decreases in NADP-malate dehydrogenase activity (but not protein levels) and pyridine nucleotide content. Antisense repression of CP12 also led to significant changes in carbon partitioning, with increased carbon allocation to the cell wall and the organic acids malate and fumarate and decreased allocation to starch and soluble carbohydrates. Severe decreases were also seen in 2-oxoglutarate content, a key indicator of cellular carbon sufficiency. The data presented here indicate that in tobacco, CP12 has a role in redox-mediated regulation of carbon partitioning from the chloroplast and provides strong in vivo evidence that CP12 is required for normal growth and development in plants.</jats:p
TANAMI - Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry
We present a summary of the observation strategy of TANAMI (Tracking Active
Galactic Nuclei with Austral Milliarcsecond Interferometry), a monitoring
program to study the parsec-scale structure and dynamics of relativistic jets
in active galactic nuclei (AGN) of the Southern Hemisphere with the Australian
Long Baseline Array (LBA) and the trans-oceanic antennas Hartebeesthoek, TIGO,
and O'Higgins. TANAMI is focusing on extragalactic sources south of -30 degrees
declination with observations at 8.4 GHz and 22 GHz every ~2 months at
milliarcsecond resolution. The initial TANAMI sample of 43 sources has been
defined before the launch of the Fermi Gamma Ray Space Telescope to include the
most promising candidates for bright gamma-ray emission to be detected with its
Large Area Telescope (LAT). Since November 2008, we have been adding new
sources to the sample, which now includes all known radio- and gamma-ray bright
AGN of the Southern Hemisphere. The combination of VLBI and gamma-ray
observations is crucial to understand the broadband emission characteristics of
AGN and the nature of relativistic jets.Comment: Conference proceedings "2009 Fermi Symposium" eConf Proceedings
C09112
Phase Fluctuations and Pseudogap Properties: Influence of Nonmagnetic Impurities
The presence of nonmagnetic impurities in a 2D ``bad metal'' depresses the
superconducting Berezinskii-Kosterlitz-Thouless transition temperature, while
leaving the pairing energy scale unchanged. Thus the region of the pseudogap
non-superconducting phase, where the modulus of the order parameter is non-zero
but its phase is random, and which opens at the pairing temperature is
substantially bigger than for the clean system. This supports the premise that
fluctuations in the phase of the order parameter can in principle describe the
pseudogap phenomena in high- materials over a rather wide range of
temperatures and carrier densities. The temperature dependence of the bare
superfluid density is also discussed.Comment: 11 pages, LaTeX, 1 EPS figure; final version to appear in
Low.Temp.Phy
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