Bottom Morphology and Tectonics of the Southern Ocean

The paper gives the brief characteristics of the main bottom morpho-structures, revealed as the result of geomorphological analysis and according to separate geophysical data taken by expeditions of different countries. Differences in the type of the earth\u27s crust under ocean floor serve as the main taxonomic principle. Thus the shelf on the margin of Antarctica is characterized by purely continental features. To the transition continental-oceanic area belong the continental slopes, the zones of island arcs and the basins of marginal seas. Structure areas of the oceanic crust are represented by gigantic depressions of oceanic basins and arched uplifts of oceanic swells, by linear folded-block elevations of median ridges, by oceanic trenches and their marginal swells. Seven bathymetrical, geomorphological and tectonic maps have been compiled for "The Atlas of the Antarctic"

Investigation of Structure, Chemical and Phase Composition of Silicon Spring Steel Scale

The article presents the results of investigation of structure, chemical and phase composition of scale formed on siliceous spring steels during high-temperature heating prior to rolling. It is established that in 40S2 steel, the hematite layer bordering furnace atmosphere has a minimum thickness of about 40–60 μm, the magnetite layer has thickness of 250 ± 280 μm, the largest thickness of 800 ± 900 μm has wustite layer with secondary ferriferous oxide released during cooling, bordering the steel surface. The scale layer adjacent to the steel surface is characterized by a much greater macrostructural, chemical, and phase inhomogeneity. In addition towustite–ferriferous oxide mixture, iron silicates with an increased silicon content are present. Approaching the steel surface, the number of zones enriched with silicon increases. When 60S2ChA steel is heated to 1180–1200∘С, zones enriched with silicon are observed in the scale at a distance of 200 ± 250 μm from the metal surface, and when heated to temperatures of 1310 ± 1315∘C at a much larger distance, reaching700–800 μm. Keywords: scale, steel heating, siliceous springs steel, scale microstructur

Predicting Academic Outcomes for Third Grade Students: Examining the Reading Achievement of Diverse Students Using the Diagnostic Lens of the Dynamic Indicators of Basic Early Literacy Skills

Despite the billions of dollars spent in the last forty years, America\u27s efforts toward closing the achievement gaps among diverse learners and their receptive counterparts have not been realized. Limitations noted in previous research discussed the need to examine the unique contributions of diverse learner variables as a way of determining their specific academic needs. The purpose of this study was to examine the intra- and inter-group growth trajectories of two diverse student groups (English Language Learners and Students with Specific Learning Disabilities) on reading achievement. The study employed a longitudinal, quasi-experimental research design utilizing archival data from 26,947 students\u27 files to answer two research questions. The first research question examined growth relationships between 3rd grade English Language Learner student categories on reading achievement while holding gender and socio-economic variables constant. The second research question explored the extent to which the initial levels and slopes of 3rd grade students with specific learning disabilities differed across racial and ethnic groups. Growth curve analyses were employed to answer both research questions. Findings revealed significant intercept and slope relationships for the two groups on reading fluency measures. Significant differences were found between the reference group (i.e., Non-ELL females who were ineligible for free and or reduced lunch) and two of the ELL subgroups. The slope relationships were only significant for ELL students (ELL-LY) who were in the currently enrolled (i.e., receiving some type of ELL instructional support or service) category. Gender and socio-economic variables were significant suggesting a negative influence on initial reading levels. Reading fluency (DORF) achievement findings relative to students with disabilities and their race and ethnic subgroups revealed White students\u27 initial DORF scores were significantly different from Hispanic and Black students\u27 scores. Race and ethnic slope variables were insignificant and homogeneous in nature. A discussion about these findings and their implications for closing the achievement gap for diverse students is provided in the document

Selective IT neurons are selective along many dimensions

Our visual abilities are unsurpassed because of a sophisticated code for objects located in the inferior temporal (IT) cortex. This code has remained a mystery because IT neurons show extremely diverse shape selectivity with no apparent organizing principle. Here, we show that there is an intrinsic component to selectivity in IT neurons. We tested IT neurons on distinct shapes and their parametric variations and asked whether neurons selective along one dimension were also selective along others. Selective neurons responded to fewer shapes and were narrowly tuned to local variations of these shapes, both along arbitrary morph lines and along variations in size, position, or orientation. For a subset of neurons, selective neurons were selective for both shape and texture. Finally, selective neurons were also more invariant in that they preserved their shape preferences across changes in size, position, and orientation. These observations indicate that there is an intrinsic constraint on the sharpness of tuning for the features coded by each IT neuron, making it always sharply tuned or always broadly tuned along all dimensions. We speculate that this may be an organizing principle throughout visual cortex

Texture discriminability in monkey inferotemporal cortex predicts human texture perception

Shape and texture are both important properties of visual objects, but texture is relatively less understood. Here, we characterized neuronal responses to discrete textures in monkey inferotemporal (IT) cortex and asked whether they can explain classic findings in human texture perception. We focused on three classic findings on texture discrimination: 1) it can be easy or hard depending on the constituent elements; 2) it can have asymmetries, and 3) it is reduced for textures with randomly oriented elements. We recorded neuronal activity from monkey inferotemporal (IT) cortex and measured texture perception in humans for a variety of textures. Our main findings are as follows: 1) IT neurons show congruent selectivity for textures across array size; 2) textures that were easy for humans to discriminate also elicited distinct patterns of neuronal activity in monkey IT; 3) texture pairs with asymmetries in humans also exhibited asymmetric variation in firing rate across monkey IT; and 4) neuronal responses to randomly oriented textures were explained by an average of responses to homogeneous textures, which rendered them less discriminable. The reduction in discriminability of monkey IT neurons predicted the reduced discriminability in humans during texture discrimination. Taken together, our results suggest that texture perception in humans is likely based on neuronal representations similar to those in monkey IT