Guidelines for Teaching Object Orientation with Java

How to best teach object orientation to first year students is currently a topic of much debate. One of the tools suggested to aid in this task is BlueJ, an integrated development environment specifically designed for teaching. BlueJ supports a unique style of introduction of OO concepts. In this paper we discuss a set of problems with OO teaching, present some guidelines for better course design and show how BlueJ can be used to make significant improvements to introductory OO courses. We end by esenting a description of a possible project sequence using this teaching approach

An Investigation of Students’ Use of a Computational Science Simulation in an Online High School Physics Class

Science educators have begun to explore how students have opportunities to not only view and manipulate simulations, but also to analyze the complex sources of data they generate. While scholars have documented the characteristics and the effects of using simulations as a source of data in face-to-face, K-12 classrooms, how simulations can be taken up and used in such a way in fully-online classes is less-explored. In this study, we present results from our initial qualitative investigation of students’ use of a simulation in such a way across three lessons in an online, Advanced Placement high school physics class. In all, 13 students participated in the use of a computational science simulation that we adapted to output quantitative data across the lesson sequence. Students used the simulation and developed a class data set, which students then used to understand, interpret, and model a thermodynamics-related concept and phenomenon. We explored the progression of students’ conceptual understanding across the three lessons, students’ perceptions of the strengths and weaknesses of the simulation, and how students balanced explaining variability and being able to interpret their model of the class data set. Responses to embedded assessment questions indicated that a few developed more sophisticated conceptual understanding of the particle nature of matter and how it relates to diffusion, while others began the lesson sequence with an already-sophisticated understanding, and a few did not demonstrate changes in their understanding. Students reported that the simulation helped to make a complex idea more accessible and useful and that the data generated by the simulation made it easier to understand what the simulation was representing. When analyzing the class data set, some students focused on fitting the data, not considering the interpretability of the model as much, whereas other students balanced model fit with interpretability and usefulness. In all, findings suggest that the lesson sequence had educational value, but that modifications to the design of the simulation and lesson sequence and to the technologies used could enhance its impact. Implications and recommendations for future research focus on the potential for simulations to be used to engage students in a variety of scientific and engineering practices in online science classes

An Investigation of Students’ Use of a Computational Science Simulation in an Online High School Physics Class

Science educators have begun to explore how students have opportunities to not only view and manipulate simulations, but also to analyze the complex sources of data they generate. While scholars have documented the characteristics and the effects of using simulations as a source of data in face-to-face, K-12 classrooms, how simulations can be taken up and used in such a way in fully-online classes is less-explored. In this study, we present results from our initial qualitative investigation of students’ use of a simulation in such a way across three lessons in an online, Advanced Placement high school physics class. In all, 13 students participated in the use of a computational science simulation that we adapted to output quantitative data across the lesson sequence. Students used the simulation and developed a class data set, which students then used to understand, interpret, and model a thermodynamics-related concept and phenomenon. We explored the progression of students’ conceptual understanding across the three lessons, students’ perceptions of the strengths and weaknesses of the simulation, and how students balanced explaining variability and being able to interpret their model of the class data set. Responses to embedded assessment questions indicated that a few developed more sophisticated conceptual understanding of the particle nature of matter and how it relates to diffusion, while others began the lesson sequence with an already-sophisticated understanding, and a few did not demonstrate changes in their understanding. Students reported that the simulation helped to make a complex idea more accessible and useful and that the data generated by the simulation made it easier to understand what the simulation was representing. When analyzing the class data set, some students focused on fitting the data, not considering the interpretability of the model as much, whereas other students balanced model fit with interpretability and usefulness. In all, findings suggest that the lesson sequence had educational value, but that modifications to the design of the simulation and lesson sequence and to the technologies used could enhance its impact. Implications and recommendations for future research focus on the potential for simulations to be used to engage students in a variety of scientific and engineering practices in online science classes

Negotiated Development Denial Meets People\u27s Court: Del Monte Dunes Brings New Wildcards to Exactions Law

The United States Supreme Court Answered YES to the $1.45 million over exaction question for 1999. In City of Monterey v. Del Monte Dunes at Monterey Ltd., a unanimous court extended the scope of compensatory takings review beyond land dedication conditions into the realm of regulatory denial. Justice Kennedy\u27s opinion vitalized the legitimate state interests test from Agins v. City of Tiburon to sustain an inverse condemnation conclusion and damage award to the frustrated developer. A majority of the court also concurred that the trial court may delegate this takings conclusion to the jury under federal civil rights law. The activation of Agins\u27 substantive takings test in such challenges and the prospect of continued lay application of constitutional law to development restrictions add uncertain dimensions to exactions litigation at the millennium. In Del Monte Dunes, the Court also distinguished the instant development denial of an inverse condemnation claim from the land dedication conditions at issue in Dolan v. City of Tigard. This distinction enabled the unanimous Court to uphold the trial verdict based on Agins and avoid elements of the Ninth Circuit\u27s reasoning invoking the Dolan rough proportionality test. Other recent federal and state decisions also decline to extend Dolan\u27s applicability beyond individual land dedication development conditions to other forms of economic exactions. This year\u27s exactions and impact fee report focuses on Del Monte Dunes, namely its effects on negotiated development, trial practice, and on regulatory takings doctrine as defined by judges and juries in civil rights litigation

Negotiated Development Denial Meets People\u27s Court: Del Monte Dunes Brings New Wildcards to Exactions Law

The United States Supreme Court Answered YES to the $1.45 million over exaction question for 1999. In City of Monterey v. Del Monte Dunes at Monterey Ltd., a unanimous court extended the scope of compensatory takings review beyond land dedication conditions into the realm of regulatory denial. Justice Kennedy\u27s opinion vitalized the legitimate state interests test from Agins v. City of Tiburon to sustain an inverse condemnation conclusion and damage award to the frustrated developer. A majority of the court also concurred that the trial court may delegate this takings conclusion to the jury under federal civil rights law. The activation of Agins\u27 substantive takings test in such challenges and the prospect of continued lay application of constitutional law to development restrictions add uncertain dimensions to exactions litigation at the millennium. In Del Monte Dunes, the Court also distinguished the instant development denial of an inverse condemnation claim from the land dedication conditions at issue in Dolan v. City of Tigard. This distinction enabled the unanimous Court to uphold the trial verdict based on Agins and avoid elements of the Ninth Circuit\u27s reasoning invoking the Dolan rough proportionality test. Other recent federal and state decisions also decline to extend Dolan\u27s applicability beyond individual land dedication development conditions to other forms of economic exactions. This year\u27s exactions and impact fee report focuses on Del Monte Dunes, namely its effects on negotiated development, trial practice, and on regulatory takings doctrine as defined by judges and juries in civil rights litigation

The ACS Survey of Galactic Globular Clusters: M54 and Young Populations in the Sagittarius Dwarf Spheroidal Galaxy

We present new Hubble Space Telescope photometry of the massive globular cluster M54 (NGC 6715) and the superposed core of the tidally disrupted Sagittarius (Sgr) dSph galaxy as part of the ACS Survey of Galactic Globular Clusters. Our deep (F606W~26.5), high-precision photometry yields an unprecedentedly detailed color-magnitude diagram showing the extended blue horizontal branch and multiple main sequences of the M54+Sgr system. The distance and reddening to M54 are revised usingboth isochrone and main-sequence fitting to (m-M)_0=17.27 and E(B-V)=0.15. Preliminary assessment finds the M54+Sgr field to be dominated by the old metal-poor populations of Sgr and the globular cluster. Multiple turnoffs indicate the presence of at least two intermediate-aged star formation epochs with 4 and 6 Gyr ages and [Fe/H]=-0.4 to -0.6. We also clearly show, for the first time, a prominent, 2.3 Gyr old Sgr population of near-solar abundance. A trace population of even younger (0.1-0.8 Gyr old), more metal-rich ([Fe/H]\sim0.6) stars is also indicated. The Sgr age-metallicity relation is consistent with a closed-box model and multiple (4-5) star formation bursts over the entire life of the satellite, including the time since Sgr began disrupting.Comment: Accepted to ApJ Letter; 11 pages, 2 figures; figure 1 uploaded as jpg; paper in ApJ format with full-resolution figures available at: http://www.astro.ufl.edu/~ata/public_hstgc/paperIV/paperIV.p

High-pulse energy supercontinuum laser for high-resolution spectroscopic photoacoustic imaging of lipids in the 1650-1850 nm region

We propose a cost-effective high-pulse energy supercontinuum (SC) source based on a telecom range diode laser-based amplifier and a few meters of standard single-mode optical fiber, with a pulse energy density as high as ∼25 nJ/nm in the 1650-1850 nm regime (factor >3 times higher than any SC source ever used in this wavelength range). We demonstrate how such an SC source combined with a tunable filter allows high-resolution spectroscopic photoacoustic imaging and the spectroscopy of lipids in the first overtone transition band of C-H bonds (1650-1850 nm). We show the successful discrimination of two different lipids (cholesterol and lipid in adipose tissue) and the photoacoustic cross-sectional scan of lipid-rich adipose tissue at three different locations. The proposed high-pulse energy SC laser paves a new direction towards compact, broadband and cost-effective source for spectroscopic photoacoustic imaging

Imaging Active Infection in vivo Using D-Amino Acid Derived PET Radiotracers.

Occult bacterial infections represent a worldwide health problem. Differentiating active bacterial infection from sterile inflammation can be difficult using current imaging tools. Present clinically viable methodologies either detect morphologic changes (CT/ MR), recruitment of immune cells (111In-WBC SPECT), or enhanced glycolytic flux seen in inflammatory cells (18F-FDG PET). However, these strategies are often inadequate to detect bacterial infection and are not specific for living bacteria. Recent approaches have taken advantage of key metabolic differences between prokaryotic and eukaryotic organisms, allowing easier distinction between bacteria and their host. In this report, we exploited one key difference, bacterial cell wall biosynthesis, to detect living bacteria using a positron-labeled D-amino acid. After screening several 14C D-amino acids for their incorporation into E. coli in culture, we identified D-methionine as a probe with outstanding radiopharmaceutical potential. Based on an analogous procedure to that used for L-[methyl-11C]methionine ([11C] L-Met), we developed an enhanced asymmetric synthesis of D-[methyl-11C]methionine ([11C] D-Met), and showed that it can rapidly and selectively differentiate both E. coli and S. aureus infections from sterile inflammation in vivo. We believe that the ease of [11C] D-Met radiosynthesis, coupled with its rapid and specific in vivo bacterial accumulation, make it an attractive radiotracer for infection imaging in clinical practice