What Professional Development Practices Support The Successful Integration Of Technology Within A Standards-Based Educational (SBE) System

The purpose of this quantitative study was to explore the relationship between K-12 teachers’ current technology skill level, their self-efficacy as teachers, and their attitude toward changes required to integrate 21st-century technologies into their classrooms. Twenty-five members of the teaching staff from a rural School Department in Maine participated. This study describes the following: (a) What is the relationship between teachers’ current skills/ability using technology and their attitude towards integrating 21st-century technologies in the classroom? (b) What is the relationship between teachers’ current self-efficacy towards using technology, and their capacity towards integrating 21st-century technologies in the classroom? and (c) What components of professional development, measured through survey data, are required to support change and prepare teachers to successfully integrate 21st-century technologies in the classroom? This study evaluated data from two different needs-based professional development surveys that were designed to gather individual teacher input about their technology learning needs and which were correlated to formulate a hypothesis on teacher attitudes and current practices. Relevant organizational data was collected within the School Department. This study utilized a descriptive, quantitative method employing a non-experimental design that studied the phenomena of attitude toward change. The educational research was conducted for the purpose of describing and planning improvement related to a teachers’ current skills/ability using technology and their attitude towards integrating 21st-century technologies in the classroom. Using a Likert scale, variables within the cross-sectional surveys were identified and measured carefully to identify trends in the data

Determinants of farmer adoption of organic production methods in the fresh-market produce sector in California: A logistic regression analysis

This research uses binomial and multinomial logistic regression models to identify the factors that influence farmers adoption of organic technology. Using a sample of 175 farmers growing fresh-market produce in three California counties, the first model examines farmers choice between conventional-only and organic-only production. The second model compares conventional-only and "dual-method" (combined conventional and organic) production, while the third model employs all three choices in a multinomial model. These results, which indicate that gross sales, direct marketing, number of crops and acres, farmer age, and computer usage are significant determinants, have implications on policies that regulate the organic foods sector.Production Economics,

ESTIMATION OF EXPORT DEMAND FUNCTIONS FOR U.S. WHEAT

Export demand functions for U.S. wheat were estimated for five world regions. Estimates of the effects of income, price, and nonprice variables on U.S. wheat exports were obtained using various econometric procedures. The major finding of the paper indicates that exchange rate changes have had a substantial impact on U.S. wheat exports. This result, conditioned on the aggregative nature of the study, supports the belief expressed by some researchers in recent years.Demand and Price Analysis, International Relations/Trade,

Hydrodynamic propulsion of human sperm

The detailed fluid mechanics of sperm propulsion are fundamental to our understanding of reproduction. In this paper, we aim to model a human sperm swimming in a microscope slide chamber. We model the sperm itself by a distribution of regularized stokeslets over an ellipsoidal sperm head and along an infinitesimally thin flagellum. The slide chamber walls are modelled as parallel plates, also discretized by a distribution of regularized stokeslets. The sperm flagellar motion, used in our model, is obtained by digital microscopy of human sperm swimming in slide chambers. We compare the results of our simulation with previous numerical studies of flagellar propulsion, and compare our computations of sperm kinematics with those of the actual sperm measured by digital microscopy. We find that there is an excellent quantitative match of transverse and angular velocities between our simulations and experimental measurements of sperm. We also find a good qualitative match of longitudinal velocities and computed tracks with those measured in our experiment. Our computations of average sperm power consumption fall within the range obtained by other authors. We use the hydrodynamic model, and a prototype flagellar motion derived from experiment, as a predictive tool, and investigate how sperm kinematics are affected by changes to head morphology, as human sperm have large variability in head size and shape. Results are shown which indicate the increase in predicted straight-line velocity of the sperm as the head width is reduced and the increase in lateral movement as the head length is reduced. Predicted power consumption, however, shows a minimum close to the normal head aspect ratio

Latent image diffraction from submicron photoresist gratings

Light scattering from latent images in photoresist is useful for lithographic tool characterization, process monitoring, and process control. In particular, closed‐loop control of lithographic processes is critical for high yield, low cost device manufacturing. In this work, we report use of pulsed laser diffraction from photoresist latent images in 0.24 μm pitch distributed feedback laser gratings. Gated detection of pulsed light scattering permits high spatial resolution probing using ultraviolet light without altering the latent image. A correlation between latent image and etched grating diffraction efficiencies is demonstrated and shows the value of "upstream" monitoring

Past trauma and future choices: Differences in discounting in low-income, urban African Americans

AbstractBackgroundExposure to traumatic events is surprisingly common, yet little is known about its effect on decision making beyond the fact that those with post-traumatic stress disorder are more likely to have substance-abuse problems. We examined the effects of exposure to severe trauma on decision making in low-income, urban African Americans, a group especially likely to have had such traumatic experiences.MethodParticipants completed three decision-making tasks that assessed the subjective value of delayed monetary rewards and payments and of probabilistic rewards. Trauma-exposed cases and controls were propensity-matched on demographic measures, treatment for psychological problems, and substance dependence.ResultsTrauma-exposed cases discounted the value of delayed rewards and delayed payments, but not probabilistic rewards, more steeply than controls. Surprisingly, given previous findings that suggested women are more affected by trauma when female and male participants’ data were analyzed separately, only the male cases showed steeper delay discounting. Compared with nonalcoholic males who were not exposed to trauma, both severe trauma and alcohol-dependence produced significantly steeper discounting of delayed rewards.ConclusionsThe current study shows that exposure to severe trauma selectively affects fundamental decision-making processes. Only males were affected, and effects were observed only on discounting delayed outcomes (i.e. intertemporal choice) and not on discounting probabilistic outcomes (i.e. risky choice). These findings are the first to show significant differences in the effects of trauma on men's and women's decision making, and the selectivity of these effects has potentially important implications for treatment and also provides clues as to underlying mechanisms.</jats:sec

Hot Subdwarf Stars Among the Objects Rejected from the PG Catalog: a First Assessment Using GALEX Photometry

The hot subdwarf (sd) stars in the Palomar Green (PG) catalog of ultraviolet excess (UVX) objects play a key role in investigations of the frequency and types of binary companions and the distribution of orbital periods. These are important for establishing whether and by which channels the sd stars arise from interactions in close binary systems. It has been suggested that the list of PG sd stars is biased by the exclusion of many stars in binaries, whose spectra show the Ca II K line in absorption. A total of 1125 objects that were photometrically selected as candidates were ultimately rejected from the final PG catalog using this K-line criterion. We study 88 of these "PG-Rejects" (PGRs), to assess whether there are significant numbers of unrecognized sd stars in binaries among the PGR objects. The presence of a sd should cause a large UVX. We assemble GALEX, Johnson V, and 2MASS photometry and compare the colors of these PGR objects with those of known sd stars, cool single stars, and hot+cool binaries. Sixteen PGRs were detected in both the far- and near- ultraviolet GALEX passbands. Eleven of these, plus the 72 cases with only an upper limit in the far-ultraviolet band, are interpreted as single cool stars. Of the remaining five stars, three are consistent with being sd stars paired with a cool main sequence companion, while two may be single stars or composite systems of another type. We discuss the implications of these findings for the 1125 PGR objects as a whole. (slightly abridged)Comment: 32 pages with 3 figures and 4 tables. Uses AASTEX style files. To be published in The Astronomical Journal (August 2009 issue