A Statewide Implementation of the Critical Features of Professional Development: Impact on Teacher Outcomes

This study is focused on a statewide implementation of the core conceptual framework for effective professional development in the United States. and associated impact on teacher quality and attitudes. The framework included content focus, active learning, coherence, duration, and collective participation. There were 252 participants in the study, who were involved in one of the five science or six mathematics programs. Findings indicated a significant impact on teacher quality for all participating programs. Teacher attitudes were positive at the baseline, and remained positive with some improvement at the end of the program. However, teacher perceived preparedness increased significantly across the duration of the program. Discussion of the findings and implications for professional development programs internationally are shared.     

A variational approach to define robustness for parametric multiobjective optimization problems

In contrast to classical optimization problems, in multiobjective optimization several objective functions are considered at the same time. For these problems, the solution is not a single optimum but a set of optimal compromises, the so-called Pareto set. In this work, we consider multiobjective optimization problems that additionally depend on an external parameter ${\lambda \in \mathbb{R}}$ , so-called parametric multiobjective optimization problems. The solution of such a problem is given by the λ-dependent Pareto set. In this work we give a new definition that allows to characterize λ-robust Pareto points, meaning points which hardly vary under the variation of the parameter λ. To describe this task mathematically, we make use of the classical calculus of variations. A system of differential algebraic equations will turn out to describe λ-robust solutions. For the numerical solution of these equations concepts of the discrete calculus of variations are used. The new robustness concept is illustrated by numerical examples.     

Anti-Self-Dual Instantons with Lagrangian Boundary Conditions I: Elliptic Theory

We study nonlocal Lagrangian boundary conditions for anti-self-dual instantons on 4-manifolds with a space-time splitting of the boundary. We establish the basic regularity and compactness properties (assuming L^p-bounds on the curvature for p>2) as well as the Fredholm theory in a compact model case. The motivation for studying this boundary value problem lies in the construction of an instanton Floer homology for 3-manifolds with boundary. The present paper is part of a program proposed by Salamon for the proof of the Atiyah-Floer conjecture for homology-3-spheres.Acknowledgement I would like to thank Dietmar Salamon for his constant help and encouragement in pursuing this project. Part of this research was supported by the Swiss National Science Foundation.     

Tip-enhanced Raman scattering: Influence of the tip-surface geometry on optical resonance and enhancement

The tip-sample distance (z) dependence of tip-enhanced Raman scattering (TERS) has been investigated. The intensities of both, the Raman lines and the broad TERS background, exhibit strong decays with increasing z, which are nearly complete within 10 nm withdrawal of the STM tip in z direction. Interestingly, the maximum of the broad Lorentzian-shaped TER background is substantially blue shifted in energy with z. This effect is ascribed to a corresponding blue shift of the energies of localized plasmon modes upon tip retraction. Both experimental results fit very well data of a simple theoretical near-field model.     

Miniaturized highly brilliant diode laser modules for future display applications

We demonstrate diode laser modules with high spectral radiance larger than 1 GW/cm²/sr/nm in the visible spectral range. These highly brilliant laser light sources enable the development of next-generation 3D displays. About 1W output power from small-sized modules was achieved at 635 nm by direct diode laser emission and at 530 nm using single pass second harmonic generation (SHG) of a highly brilliant near-infrared laser diode.     

Anti-Self-Dual Instantons with Lagrangian Boundary Conditions II: Bubbling

We study bubbling phenomena of anti-self-dual instantons on where Σ is a closed Riemann surface. The instantons satisfy a global Lagrangian boundary condition on each boundary slice . The main results establish the energy quantization and removal of singularities near such boundary slices. This completes the analytic foundations for the definition of a new instanton Floer homology for 3-manifolds with boundary. In the interior case, for anti-self-instantons on our methods provide a new approach to the removable singularity theorem by Sibner-Sibner for codimension 2 singularities with a holonomy condition.     

Antileishmanial Anthracene Endoperoxides: Efficacy In Vitro,Mechanisms and Structure-Activity Relationships

Leishmaniasis is a vector-borne disease caused by protozoal Leishmania parasites. Previous studies have shown that endoperoxides (EP) can selectively kill Leishmania in host cells. Therefore, we studied in this work a set of new anthracene-derived EP (AcEP) together with their non-endoperoxidic analogs in model systems of Leishmania tarentolae promastigotes (LtP) and J774 macrophages for their antileishmanial activity and selectivity. The mechanism of effective compounds was explored by studying their reaction with iron (II) in chemical systems and in Leishmania. The correlation of structural parameters with activity demonstrated that in this compound set, active compounds had a LogP_OW larger than 3.5 and a polar surface area smaller than 100 Ų. The most effective compounds (IC₅₀ in LtP < 2 µM) with the highest selectivity (SI > 30) were pyridyl-/tert-butyl-substituted AcEP. Interestingly, also their analogs demonstrated activity and selectivity. In mechanistic studies, it was shown that EP were activated by iron in chemical systems and in LtP due to their EP group. However, the molecular structure beyond the EP group significantly contributed to their differential mitochondrial inhibition in Leishmania. The identified compound pairs are a good starting point for subsequent experiments in pathogenic Leishmania in vitro and in animal models.     

Hierarchical self-assembly of aminopyrazole peptides into nanorosettes in water

Self-association of aminopyrazole peptide hybrid 1 leads to stacked nanorosettes. This remarkable, well-ordered structure obeys the laws of nucleic acid self-assembly. In a strictly hierarchical process, formation of aminopyrazole "base" triplets via a hydrogen bond network is accompanied by pi-stacking with a second rosette and final dimerization of two double rosettes to a four-layer superstructure, stabilized by a six-fold half-crown alkylammonium lock. The final complex is soluble in organic as well as in aqueous solution. It was characterized in the solid state by X-ray crystallography, in water by NMR spectroscopy, and in silico by quantum chemical shift calculation. All these methods provide strong evidence for the same hexameric complex geometry. Its structural features bear striking similarity to nucleic acid architectures and their peptidic counterparts, especially alanyl-PNA. The whole self-assembly process is highly solvent- and temperature-dependent and occurs with a high degree of cooperativity--no intermediates are observed. Formation and dissociation of the nanorosette, however, are kinetically slow. The limitation to a hexameric aggregate can be explained by six sterically demanding valine residues, whose replacement by alanines may result in formation of infinite fibers.     

Density functional theory study of water adsorption on FeOOH surfaces

Using density functional theory (DFT) calculations with an on-site Coulomb repulsion term, we study the composition, stability, and electronic properties of the most common FeOOH surfaces goethite(101), akaganeite(100), and lepidocrocite(010), and their interaction with water. Despite the differences in surface structure, the trends in surface stability of these FeOOH polymorphs exhibit remarkable similarities. We find that the reactivity and the binding configuration of adsorbates depend strongly on the coordination of surface iron: at the fourfold coordinated Fe2 site water is chemisorbed, whereas at the fivefold coordinated Fe1 water is only loosely bound with hydrogen pointing towards the surface. Our results show that the oxidation state of surface iron can be controlled by the surface termination where ferryl (Fe^4 +) species emerge for oxygen terminated surfaces and ferrous iron (Fe^2 +) at iron and water terminations leading to a reduced band gap. In contrast, the fully hydroxylated surfaces, identified as stable surface configurations at standard conditions from the surface phase diagram, show electronic properties and band gaps closest to bulk FeOOH with ferric surface iron (Fe^3 +). Only in the case of goethite(101), a termination with mixed surface hydroxyl and aquo groups is stabilized.