Measuring Reform Practices in Science and Mathematics Classrooms: The Reformed Teaching Observation Protocol

The National Science Foundation has funded 22 Collaboratives for Excellence in Teacher Preparation. Despite the remarkable allocation of resources to this effort, it has proven exceptionally difficult to demonstrate the effectiveness of collaborative reform. In large part, this has resulted because of the difficulty of defining and measuring reform. The Reformed Teaching Observation Protocol (RTOP) was designed by the Evaluation Facilitation Group of the Arizona Collaborative for Excellence in the Preparation of Teachers (ACEPT). It is a 25‐item classroom observation protocol that is (a) standards based, (b) inquiry oriented, and (c) student centered. This instrument has provided the definition for reform and the basis for evaluation of the ACEPT collaborative. The data upon which this report is based were collected over a period of more than 2 years from 153 public school, college, and university mathematics and science classrooms. A trained team of observers consisting of two faculty members and seven graduate students was able to achieve exceptionally high levels of interrater reliability. Internal consistency, as estimated by Cronbach's alpha, was also remarkably high. Correlation coefficients ranging from 0.88 to 0.97 between RTOP scores for classrooms, and mean normalized gain scores for students in those classrooms on achievement measures demonstrate that reform, as defined by ACEPT and measured by the RTOP, has been effective.     

A-B quasiconvexity and implicit partial differential equations

The study of existence of solutions of boundary-value problems for differential inclusions where , is an open subset of , is a compact set, and B is a -valued first order differential operator, is undertaken. As an application, minima of the energy for large magnetic bodies where the magnetization is taken with values on the unit sphere is the induced magnetic field satisfying and is the anisotropic energy density, and the applied external magnetic field is given by , are fully characterized. Setting with , it is shown that E admits a minimizer with if and only if either 0 is on a face of or , where denotes the convex hull of Z. Received: 6 November 2000 / Accepted: 23 January 2001 / Published online: 23 April 2001     

Synthese neuer Indolderivate

The synthesis of the ,-unsaturated ketones4, 5 und6 via the regiospecific aldol- andWittigreaction with some indolealdehydes is described.4 and5 are stable enough for NaBH₄-reduction to the corresponding alcohols.

     

On the Estimation of Jump Points in Smooth Curves

Two-step methods are suggested for obtaining optimal performance in the problem of estimating jump points in smooth curves. The first step is based on a kernel-type diagnostic, and the second on local least-squares. In the case of a sample of size n the exact convergence rate is n ^{– 1}, rather than n ^{– 1 +} (for some > 0) in the context of recent one-step methods based purely on kernels, or n ^{– 1} (log n)^{1 +} for recent techniques based on wavelets. Relatively mild assumptions are required of the error distribution. Under more stringent conditions the kernel-based step in our algorithm may be used by itself to produce an estimator with exact convergence rate n ^{– 1} (log n)^1/2. Our techniques also enjoy good numerical performance, even in complex settings, and so offer a viable practical alternative to existing techniques, as well as providing theoretical optimality.     

Ionic‐Liquid‐Based Polymer Electrolytes for Battery Applications

The advent of solid‐state polymer electrolytes for application in lithium batteries took place more than four decades ago when the ability of polyethylene oxide (PEO) to dissolve suitable lithium salts was demonstrated. Since then, many modifications of this basic system have been proposed and tested, involving the addition of conventional, carbonate‐based electrolytes, low molecular weight polymers, ceramic fillers, and others. This Review focuses on ternary polymer electrolytes, that is, ion‐conducting systems consisting of a polymer incorporating two salts, one bearing the lithium cation and the other introducing additional anions capable of plasticizing the polymer chains. Assessing the state of the research field of solid‐state, ternary polymer electrolytes, while giving background on the whole field of polymer electrolytes, this Review is expected to stimulate new thoughts and ideas on the challenges and opportunities of lithium‐metal batteries.     

Glucose–Nucleobase Pseudo Base Pairs: Biomolecular Interactions within DNA

Noncovalent forces rule the interactions between biomolecules. Inspired by a biomolecular interaction found in aminoglycoside–RNA recognition, glucose‐nucleobase pairs have been examined. Deoxyoligonucleotides with a 6‐deoxyglucose insertion are able to hybridize with their complementary strand, thus exhibiting a preference for purine nucleobases. Although the resulting double helices are less stable than natural ones, they present only minor local distortions. 6‐Deoxyglucose stays fully integrated in the double helix and its OH groups form two hydrogen bonds with the opposing guanine. This 6‐deoxyglucose‐guanine pair closely resembles a purine‐pyrimidine geometry. Quantum chemical calculations indicate that glucose‐purine pairs are as stable as a natural T‐A pair.     

Interpolation Problems for Certain Classes of Slice Hyperholomorphic Functions

A general interpolation problem (which includes as particular cases the Nevanlinna–Pick and Carathéodory–Fejér interpolation problems) is considered in two classes of slice hyperholomorphic functions of the unit ball of the quaternions. In the Hardy space of the unit ball we present a Beurling–Lax type parametrization of all solutions, and the formula for the minimal norm solution. In the class of functions slice hyperholomorphic in the unit ball and bounded by one in modulus there (that is, in the class of Schur functions in the present framework) we present a necessary and sufficient condition for the problem to have a solution, and describe the set of all solutions in the indeterminate case.