Many new curricular andinstructionalmodels must be developedor adapted as the nationmoves towards educational reform in science classrooms. This article describes how problem-based learning, an innovative curricular and instructionalmodel developed inmedical graduate schoolprograms, has been adapted for use in elementary and high school settings. Included in the integration of problem-based learning and science are components of allproblem-based episodes including initiating learning with an ill-structuredproblem, using the problem to structure the learning agenda, and teacher as metacognitive coach, wth important goals of a reformed science curriculum such as learning based on concepts of significance, student-designed experiments, and development of scientific reasoning skills, The community ofscience educators seems poised for action. There is widespread agreement that an understanding of science is increasingly critical to effective functioning in a democratic society, as issues

Classroom instruction in problem solving often takes the form of presenting neat, verification-style problems to students at the end of a period of learning. This practice stands in stark contrast to professional problem solving, where the problem comes first, and is a catalyst for investigation and learning. Problem-based learning provides students with an opportunity to grapple with realistic, ill-structured problems using the same kinds of techniques and habits of mind professionals use. The problem-based curriculum and instruction design puts students in the role of professional problem solvers by designing instruction around the investigation of an ill-structured problem. Teachers act as metacognitive coaches and tutors instead of “experts” who have the “right answer” to the problem. Two different applications of problem-based learning at the Illinois Mathematics and Science Academy are described in this article. One application is in an interdisciplinary senior elective course entitled Science, Society and the Future where problems investigate modern dilemmas resulting in modern advances in science and technology; the other is in a more traditional sophomore required course, American Studies, where the problems studied provide students with a feel for the critical decisions which drove the development of the Nation. A description of research projects underway to document the effectiveness of the program is also provided.

The high dose+adjuvant (100 μg antigen+AlOH) formulation administered at 0-7-30 days elicited the best immune response profile, including functional antibody responses, through Day 180 and was selected for use in subsequent clinical trials.

Hydrophobic ion pairing (HIP) can successfully increase the drug loading and control the release kinetics of ionizable hydrophilic drugs, addressing challenges that prevent these molecules from reaching the clinic. Nevertheless, polymeric nanoparticle (PNP) formulation development requires trial-and-error experimentation to meet the target product profile, which is laborious and costly. Herein, we design a preformulation framework (solid-state screening, computational approach, and solubility in PNP-forming emulsion) to understand counterion–drug–polymer interactions and accelerate the PNP formulation development for HIP systems. The HIP interactions between a small hydrophilic molecule, AZD2811, and counterions with different molecular structures were investigated. Cyclic counterions formed amorphous ion pairs with AZD2811; the 0.7 pamoic acid/1.0 AZD2811 complex had the highest glass transition temperature (T g; 162 °C) and the greatest drug loading (22%) and remained as phase-separated amorphous nanosized domains inside the polymer matrix. Palmitic acid (linear counterion) showed negligible interactions with AZD2811 (crystalline-free drug/counterion forms), leading to a significantly lower drug loading despite having similar log P and pK a with pamoic acid. Computational calculations illustrated that cyclic counterions interact more strongly with AZD2811 than linear counterions through dispersive interactions (offset π–π interactions). Solubility data indicated that the pamoic acid/AZD2811 complex has a lower organic phase solubility than AZD2811-free base; hence, it may be expected to precipitate more rapidly in the nanodroplets, thus increasing drug loading. Our work provides a generalizable preformulation framework, complementing traditional performance-indicating parameters, to identify optimal counterions rapidly and accelerate the development of hydrophilic drug PNP formulations while achieving high drug loading without laborious trial-and-error experimentation.

Since inexpensive computers possessing sophisticated graphics were introduced in the late 1970s, program development research has focused on syntax-directed editors that are based on the grammars of their underlying languages. The system presented here automatically generates object-oriented, syntax-directed editors for visual languages, which are described by a family of editing operations.

The object-oriented approach to software design together with the programming languages (C++, Java, and Ada95) and design notations (e.g. UML) that support this paradigm, have precipitated new interest in developing and tailoring software metrics to more effectively quantify properties of OO systems. To be specific, this research on OO software is motivated by two related problems. 1) In many computer science courses instructors are torn between two conflicting goals: (a) increasing the number and difficulty of programming assignments to raise students' problem solving skills and maturity, while on the other hand, (b) giving meaningful feedback on the correctness and quality of programs they write. To address this problem, we are developing an automated Java program grading system. This system will compare student programs to an oracle program prepared by the instructor for a given assignment. The oracle program represents the "ideal" solution. In addition to computing a quantitative score for a student program, the grading program will also provide feedback on modifications or changes the student could or should make to improve the quality of the design of his or her solution. 2)A problem that is all too common in the computing industry is software theft. This has led to much copyright infringement litigation within our court system. As an expert witness in such cases, one of the tasks I have been frequently asked to perform is evaluate two programs to determine the nature and extent of their similarity. A tool, such as our planned program grading system, is needed to facilitate the kind of analysis required in such cases. In the academic world, the equivalent to software theft is plagiarism. Therefore, as an application complementary to program grading, our proposed system will also serve as a tool for identifying "cheaters" by comparing two student programs to one another, rather than to the oracle. So, in summary, our goal is to develop the key algorithms and eventually a program analysis system that will effectively determine the similarity of two programs written in the same language. Since Java is becoming one of the most widely used programming languages, and because of its relatively "clean" syntax and semantics, Java will provide the focus for our initial investigation. Java programs are composed of three essential building blocks: packages, classes, and methods. Methods are the functional or procedural units that perform or realize the algorithms necessary to solve a computational problem. Methods are grouped with encapsulated data to define classes -new types that extend Java's set of primitive types. Finally, classes are organized into subsystems or libraries using packages. Thus, when comparing two Java programs to determine their similarity, we must establish a correspondence between the packages, classes, and methods of the two programs under consideration. This suggests we must ascertain for a given pair of units, one from each program whether or not they are sufficiently similar to warrant being identified as "matching" in our correspondence analysis. To be similar, they must be "doing the essentially the same thing" -that is, they must both serve the same computational purpose. Assuming we are successful in developing some technique for determining similarity of purpose, we are still faced with the potentially large numbers of unit-pairs that must be considered in our analysis. The sheer magnitude of our computational problem thus looms as a major obstacle to obtaining any real practical solution. Using the names of units to limit what pairs need to be compared, while certainly reducing the potential computational load, is not a very reliable strategy --- particularly if the author of one program has made a deliberate attempt to disguise similarity with another program by uniformly changing names. Thus, in an attempt to address the computational load problem and the identification problem for comparison analysis, we plan to make an initial pass over each program to categorize methods and classes according to their purpose. The rationale for this is: two units will be selected for detailed comparison analysis only if they belong to of the same purpose category. The focus of this paper, therefore, is to present definitions and examples of the purpose categories for methods and classes. How these purpose categories will be used in a larger comparison strategy is beyond the scope of this work. Refer to Lan[13] for further a more complete and detailed description of our methodology.

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