The Relationship of Scores on Dynamic Indicators of Basic Early Literacy Skills, Word Use Fluency to Word Knowledge and Shyness

Limited research has been conducted to determine the link between the Dynamic Indicators of Basic Early Literacy Skills (DD3ELS); Word Use Fluency, and reading ability. In addition, a link between the personality trait of shyness and lower performance on language tests has been established. The purpose of the present study was two fold. First this study aimed to determine how well the DIBELS Word Use Fluency indicator measures vocabulary knowledge. Second, the strength of the relationship between scores on the DIBELS measure and shyness was established. This helped to understand if Word Use Fluency underestimated the vocabulary knowledge of students who are shy. Participants included 35 second-grade students from upstate New York schools, rated by their teachers as shy or not shy. Each participant was evaluated with the DIBELS: Word Use Fluency and Oral Reading Fluency, Receptive One Word Picture Vocabulary Test, and the Expressive One Word Picture Vocabulary Test. A significant negative correlation existed between the shyness rating and Word Use Fluency. In addition Word Use Fluency was significantly correlated with expressive vocabulary for not shy students. A Multivariate Analysis of Variance indicated a significant difference between the performance of shy students and not shy students on Word Use Fluency, but no difference on the Expressive One Word Picture Vocabulary Test

Spin Blockade in Capacitively Coupled Quantum Dots

We present transport measurements on a lateral double dot produced by combining local anodic oxidation and electron beam lithography. We investigate the tunability of our device and demonstrate, that we can switch between capacitive and tunnel coupling. In the regime of capacitive coupling we observe the phenomenon of spin blockade in a magnetic field and analyze the influence of capacitive interdot coupling on this effect.Comment: 4 pages, 3 figure

Combined atomic force microscope and electron-beam lithography used for the fabrication of variable-coupling quantum dots

We have combined direct nanofabrication by local anodic oxidation with conventional electron-beam lithography to produce a parallel double quantum dot based on a GaAs/AlGaAs heterostructure. The combination of both nanolithography methods allows to fabricate robust in-plane gates and Cr/Au top gate electrodes on the same device for optimal controllability. This is illustrated by the tunability of the interdot coupling in our device. We describe our fabrication and alignment scheme in detail and demonstrate the tunability in low-temperature transport measurements.Comment: 4 pages, 3 figure

Sheared magnetospheric plasma flows and discrete auroral arcs: a quasi-static coupling model

We consider sheared flows in magnetospheric boundary layers of tangential discontinuity type, forming a structure that is embedded in a large-scale convergent perpendicular electric field. We construct a kinetic model that couples the magnetospheric structure with the topside ionosphere. The contribution of magnetospheric electrons and ionospheric electrons and ions is taken into account into the current-voltage relationship derived for an electric potential monotonically decreasing with the altitude. The solution of the current continuity equation gives the distribution of the ionospheric potential consistent with the given magnetospheric electric potential. The model shows that a sheared magnetospheric flow generates current sheets corresponding to upward field-aligned currents, field-aligned potential drops and narrow bands of precipitating energy, as in discrete auroral arcs. Higher velocity magnetospheric sheared flows have the tendency to produce brighter and slightly broader arcs. An increase in arc luminosity is also associated with enhancements of magnetospheric plasma density, in which case the structures are narrower. Finally, the model predicts that an increase of the electron temperature of the magnetospheric flowing plasma corresponds to slightly wider arcs but does not modify their luminosity

Kondo effect in a few-electron quantum ring

A small quantum ring with less than 10 electrons was studied by transport spectroscopy. For strong coupling to the leads a Kondo effect is observed and used to characterize the spin structure of the system in a wide range of magnetic fields. At small magnetic fields Aharonov-Bohm oscillations influenced by Coulomb interaction appear. They exhibit phase jumps by $\pi$ at the Coulomb-blockade resonances. Inside Coulomb-blockade valleys the Aharonov-Bohm oscillations can also be studied due to the finite conductance caused by the Kondo effect. Astonishingly, the maxima of the oscillations show linear shifts with magnetic field and gate voltage.Comment: 4 pages, 4 figure

Fingerprinting and Identification of Bacteria Present in UASB Granules Used to Treat Winery, Brewery, Distillery or Peach-lye Canning Wastewater

The effective operation of the anaerobic digestion process in an upflow anaerobic sludge blanket (UASB) bioreactoris dependent on the microbial composition of the UASB granules. The granules contain a consortium of bacteria,with a specific metabolic function for each group, contributing to the overall efficiency and stability of thebioreactor. The aim of this study was to fingerprint and identify the bacteria present in four different types of SouthAfrican UASB granules that are used to treat winery, brewery, distillery and peach-lye canning wastewaters. Thiswas done by combining conventional microbiological platings with PCR-based denaturing gradient gelelectrophoresis (DGGE) and DNA sequence analysis. Each granule type showed distinct PCR-based DGGEfingerprints with unique bands, while other bands were found to be present in all the granules, regardless of thewastewater being treated. Sixty-eight different bacteria (40 pure isolates and 28 clones) were partially sequencedand identified from the winery, brewery, distillery and peach-lye canning granules. Thirty-five percent of theidentified bacteria represented the unculturable bacteria and 65% represented the culturable bacteria, whichincluded members of the following genera: Bacillus, Pseudomonas, Bacteroides, Enterococcus, Alcaligenes,Clostridium, Shewanella, Microbacterium, Leuconostoc, Sulfurospirillum, Acidaminococcus, Vibrio, Aeromonas,Nitrospira, Synergistes, Rhodococcus, Rhodocyclus and Syntrophobacter. A DGGE marker was successfullyconstructed, representing members of the bacterial consortium in UASB granules