Science experiences for the blind in grades four, five, and six

Thesis (Ed.M.)--Boston Universit

Hemispheric specialization in selective attention and short-term memory: a fine-coarse model of left- and right-ear disadvantages.

Serial short-term memory is impaired by irrelevant sound, particularly when the sound changes acoustically. This acoustic effect is larger when the sound is presented to the left compared to the right ear (a left-ear disadvantage). Serial memory appears relatively insensitive to distraction from the semantic properties of a background sound. In contrast, short-term free recall of semantic-category exemplars is impaired by the semantic properties of background speech and is relatively insensitive to the sound’s acoustic properties. This semantic effect is larger when the sound is presented to the right compared to the left ear (a right-ear disadvantage). In this paper, we outline a speculative neurocognitive fine-coarse model of these hemispheric differences in relation to short-term memory and selective attention, and explicate empirical directions in which this model can be critically evaluated

Connecting algebra to geometry: A transition summer camp for at-risk students

The authors share how they designed curriculum for a summer algebra camp, for eighth graders in a district serving high proportions of Latino students. They discuss the impact the algebra camp had on students’ confidence in mathematics and mathematical ability

NCTM 2015 summer high school institute

NCTM’s 2015 High School Interactive Institute engaged teachers in learning opportunities to promote effective mathematics teaching. Through keynote speeches, interactive workshops, and facilitated task discussion groups, teachers reflected on current and best practices, participated in classroom-ready lessons, and collaborate with other educators

Forebrain dopamine receptors in cognitive, memory and learning processes

Neurons that utilize dopamine (DA) as a neurotransmitter have attracted great interest because of their involvement in the behavioral, endocrine and descending control of major brain functions. DA is known to exert its physiological effects on target neurons through D1-like (D1 and D5) and D2-like (D2, D3 and D4) receptor subtypes. To better understand the DA modulation of brain functions, the distribution and cellular localization of D1 and D2 DA receptors in the rat forebrain is reviewed, and their possible role in cognitive aspects of behavior is discussed. In general, DA receptors are differentially expressed and mostly distributed in different target fields of DA neurons. Both D1 and D2 receptor gene products are found in the cerebral cortex, basal ganglia and hippocampal formation, albeit in different cell groups or neuronal subpopulations, whereas D3 receptors are mainly located in limbic regions. In the cortex, mRNA signals are seen in all the areas and cortical layers except layer I. In the striatum, the most intense signal is found in the caudate-putamen, nucleus accumbens and olfactory tubercle where a large number of cells are strongly labeled for D1 and D2. In the globus pallidus only scattered D2 mRNA-containing cells are present. In contrast, no D1 or D2 messages can be seen in the ventral pallidum. In the basal forebrain, mRNA encoding the D1 receptor is detected in the islands of Calleja. The medial and lateral septal nuclei show a low D2 signal. In the amygdaloid nuclear complex, the strongest D1 receptor message is observed in the basomedial and basolateral nuclei. Conversely, the highest density of D2 mRNA-expressing cells is revealed in the central nucleus. Moderately labeled for D1 and D2 cells are scattered throughout the anterior and posterior subdivisions of the bed nucleus of stria terminalis, and within all subfields of the hippocampal formation and dentate granule cell layer. Differential regional and cellular distribution of DA receptors in the forebrain provides anatomical evidence for an area-specific regulation of the DAergic neurotransmission. It can be inferred that DA facilitates learning, memory and cognition processes via activation of both the D1 and D2 receptors.Biomedical Reviews 2005; 16: 59-75

Thurston equivalence of topological polynomials

We answer Hubbard's question on determining the Thurston equivalence class of ``twisted rabbits'', i.e. images of the ``rabbit'' polynomial under n-th powers of the Dehn twists about its ears. The answer is expressed in terms of the 4-adic expansion of n. We also answer the equivalent question for the other two families of degree-2 topological polynomials with three post-critical points. In the process, we rephrase the questions in group-theoretical language, in terms of wreath recursions.Comment: 40 pages, lots of figure

Concepts of Online Text: Examining Online Literacy Skills of Elementary Students

Reading online text presents unique challenges for elementary students as they develop and extend fundamental literacy skills to various media. Traditional assessments of concepts about print inspired the authors’ research, which applies a similar approach to address “screen handling” instead of book handling. The purpose of their ongoing research has been to develop an instrument to assess concepts related to online reading. The Concepts of Online Text (COT) assessment measures knowledge of online navigation and text features. Quantitative analysis of student performance data using the COT has the potential to provide developmental insight into elementary students’ proficiencies in conducting internet research and to provide input to teachers for targeted instruction. In this article, the authors share results from administering the instrument to 80 elementary students in first through fifth grades

The phonon theory of liquid thermodynamics

Heat capacity of matter is considered to be its most important property because it holds information about system's degrees of freedom as well as the regime in which the system operates, classical or quantum. Heat capacity is well understood in gases and solids but not in the third state of matter, liquids, and is not discussed in physics textbooks as a result. The perceived difficulty is that interactions in a liquid are both strong and system-specific, implying that the energy strongly depends on the liquid type and that, therefore, liquid energy can not be calculated in general form. Here, we develop a phonon theory of liquids where this problem is avoided. The theory covers both classical and quantum regimes. We demonstrate good agreement of calculated and experimental heat capacity of 21 liquids, including noble, metallic, molecular and hydrogen-bonded network liquids in a wide range of temperature and pressure.Comment: 7 pages, 4 figure

The Octarepeat Domain of the Prion Protein Binds Cu(II) with Three Distinct Coordination Modes at pH 7.4

The prion protein (PrP) binds Cu2+ in its N-terminal octarepeat domain. This unusual domain is comprised of four or more tandem repeats of the fundamental sequence PHGGGWGQ. Previous work from our laboratories demonstrates that at full copper occupancy, each HGGGW segment binds a single Cu2+. However, several recent studies suggest that low copper occupancy favors different coordination modes, possibly involving imidazoles from histidines in adjacent octapeptide segments. This is investigated here using a combination of X-band EPR, S-band EPR, and ESEEM, along with a library of modified peptides designed to favor different coordination interactions. At pH 7.4, three distinct coordination modes are identified. Each mode is fully characterized to reveal a series of copper-dependent octarepeat domain structures. Multiple His coordination is clearly identified at low copper stoichiometry. In addition, EPR detected copper−copper interactions at full occupancy suggest that the octarepeat domain partially collapses, perhaps stabilizing this specific binding mode and facilitating cooperative copper uptake. This work provides the first complete characterization of all dominant copper coordination modes at pH 7.4

Dynamical Belyi maps

We study the dynamical properties of a large class of rational maps with exactly three ramification points. By constructing families of such maps, we obtain infinitely many conservative maps of degree $d$; this answers a question of Silverman. Rather precise results on the reduction of these maps yield strong information on the rational dynamics.Comment: 21 page