Music\u27s Effect on Performance During Writers\u27 Workshop

This research attempted to.answer the question, how does music affect the time on task and the number of words/sentences written during writers\u27 workshop. The researcher collected data from a first grade class in an urban school. The researcher used classical music from various artists during writers\u27 workshop. Organized charts and surveys were used to collect the data. The data was analyzed to determine if their was an increase in students\u27 progress

Changes in fine structure of the frog lung induced by substances altering transcapillary exchange

Thesis (Ph.D.)--Boston UniversityIn order to evaluate the possible role of dynamic alterations, both reversible and irreversible, in the ultrastructure of the capillary wall as related to permeability, chemical substances known to alter transvascular exchange (moccasin snake venom, histamine and serotonin) were applied topically to the exposed lung of frogs, Rana pipiens and Rana catesbiana. Progressive stages of damage to lung and vascular tissues were revealed by electron microscopy. The speed of the response varied directly with the concentration and duration of application. The chemical concentrations were adjusted to produce all of the observable effects in about one half hour [TRUNCATED

The effect of sterilization on biological, organic geochemical and morphological information in natural samples

The loss of biological, organic geochemical, and morphological science information that may occur should a Mars surface sample be sterilized prior to return to earth is examined. Results of experimental studies are summarized

Promoting Leadership in the Ongoing Professional Development of Teachers: Responding to Globalization and Inclusion

This paper explores the need for innovative leadership in teacher education in the Canadian context, with a particular call for renewed professional development of current teachers. Within a country defined as multicultural, recent demographic shifts, interregional migration, growing ethnic diversity, and the emergence of a paradigm of inclusion, contemporary classrooms are evolving at a pace faster than projected. While inclusive education emerged from the growth of services for children with disabilities, it is now a concept much broader than initially con-ceived. Expanded concepts of learner differences are necessitating an urgent need for leadership in redeveloping effective training for current teachers. This paper argues that ongoing professional development must be characterized by six focus areas in order to empower teachers with pragmatic skills to balance the needs of their diverse classes. The authors conclude that a first step in this process is training for administrators who lead professional development in schools

Electron Microscope Studies of Early Stages of Sperm Penetration in Hydroides Hexagonus (Annelida) and Saccoglossus Kowalevskii (Enteropneusta)

1. The early events of sperm entry in Saccoglossus and Hydroides are described and examined in relation to present knowledge of the acrosome reaction and of egg membrane lysins. In Saccoglossus and several other species these events occur in two phases. First. The acrosome filament of the spermatozoön spans the egg membrane barriers, reaches the reactive egg protoplasm, and causes the egg to begin its fertilization reaction. Second. The filament and its connected sperm head move through the egg membrane barriers and enter the egg proper. The first phase is completed in a matter of seconds but the second phase usually requires several minutes. 2. The peripheral areas of the eggs of the two species differ as seen in sections. In Hydroides, but not in Saccoglossus, the vitelline membrane is bounded by a distinct outer border layer of small concentrically differentiated bodies and penetrated by microvilli from the egg. 3. The acrosome filament, seen in the living condition as a delicate thread in Hydroides and as an exceedingly tenuous thread in Saccoglossus, appears to be tubular in both species when seen in electron micrographs of thin sections. 4. The acrosomal region of Hydroides appears to consist of two components—a peripheral one, which may collapse during the acrosome reaction, and a central one related to the acrosome filament. 5. Deliberately induced polyspermic material was used to increase the probability of finding examples of sperm penetration in thin sections. 6. As seen in sections, areas of low electron density, interpreted as spaces or pits from which the material of the membrane is absent, surround the attached or penetrating spermatozoa. (a) In Hydroides the spaces vary greatly in many characteristics including shape, position in the membrane, and size with relation to the enclosed sperm head. In one specimen a portion of the membrane is missing from border to border; no spermatozoön is seen but immediately beneath the space is the apex of a fertilization cone. (b) In every case in which a determination could be made, the spermatozoön in the membrane has undergone its acrosome reaction. (c) In Saccoglossus some pits are found with which several spermatozoa are associated. Generally, where the spermatozoa are more numerous the pit is larger. (d) Pits similar to those seen in Saccoglossus sections are observed in living eggs. They remain in Membrane I after sperm entry. (e) From the above and other considerations it is suggested that the pits and spaces are formed by local action of a lysin or lysins emanating from the individual spermatozoön at the site of sperm entry. 7. It is considered that the suggested lysin would participate in sperm entry by eroding the membrane barrier in the vicinity of the sperm head, thus permitting the sperm head to pass through the membrane. Since the acrosome filament much earlier stimulates the egg\u27s initial fertilization response, this lysin would facilitate the second phase of the early events of sperm entry

Hes6 is required for MyoD induction during gastrulation

AbstractThe specification of mesoderm into distinct compartments sharing the same lineage restricted fates is a crucial step occurring during gastrulation, and is regulated by morphogenic signals such as the FGF/MAPK and activin pathways. One target of these pathways is the transcription factor XmyoD, which in early gastrulation is expressed in the lateral and ventral mesoderm. Expression of the hairy/enhancer of split transcription factor hes6, is also restricted to lateral and ventral mesoderm in gastrula stage Xenopus embryos, leading us to investigate whether it has a role in XmyoD regulation. In vivo, Xhes6 is required for FGF-mediated induction of XmyoD expression but not for induction of early mesoderm. The WRPW domain of Xhes6, which binds Groucho family transcriptional co-regulators, is essential for the XmyoD-inducing activity of Xhes6. Two Groucho proteins, Xgrg2 and Xgrg4, are expressed in lateral and ventral mesoderm, and inhibit expression of XmyoD. Xhes6 binds both Xgrg2 and Xgrg4 and relieves their inhibition of XmyoD expression. We also find that lowering Xhes6 expression levels blocks normal myogenic differentiation at tail bud stage. We conclude that Xhes6 is essential for XmyoD induction and acts by relieving Groucho-mediated repression of gene expression

Increasing signal-to-noise ratio in over-determined Mueller matrices

This work investigates how the signal-to-noise ratio (SNR) of an over-determined Mueller matrix can be improved by changing the method of calculation. Specifically, our investigation focused on comparing SNRs achieved using the vector methodology from the field of partial Mueller polarimetry, and the matrix methodology. We use experimentally derived measurements from an investigation into the time-varying signal produced by the Mueller matrix of an electro-optic Bismuth Silicon Oxide (BSO) crystal undergoing cyclical impact of a Helium plasma ionisation wave. Our findings show that the vector methodology is superior to the matrix methodology, with a maximum SNR of 7.54 versus 4.97. We put forth that the superiority of the vector methodology is due to its greater flexibility, which results in the Mueller matrix being calculated with better condition matrices, and higher levels of SNR in the intensity measurements used for calculation.</p