A new augmented penalty function technique for optimal control problems

This note presents an extension of the Miele—Cragg-Iyer-Levy augmented function method for finite-dimensional optimization problems to optimal control problems. A numerical study is provided.     

The decay of 235U

Twenty-eight γ-rays, ten of which are reported for the first time, have been observed in the decay of ²³⁵U, and all have been placed in a revised level scheme for ²³¹Th. Three new levels at 390.27, 317.42 and 240.82 keV respectively have been proposed and the data are in accord with he results of coincidence studies. Reduced transition probabilities of inter-band γ-ray transitions are calculated from the data and compared with theory and an estimate of the intrinsic quadrupole moment, Q_O has been computed.     

A [3+2] annulation procedure for methylenecyclopentanes

A two step sequence converts certain cyclic enones to fused methylenecyclopentanes using the annulation reagent 2-chloromethyl-3-trimethylsilylpropene.     

A second-order iterative technique for differential-integral systems

This note considers the optimal control of a system represented by nonlinear differential-integral equations with a general cost function. A second-order iterative method of solution based on the fixed-point contraction mapping principle is proposed.     

Peak alignment of urine NMR spectra using fuzzy warping

Proton nuclear magnetic resonance (1H NMR) spectroscopic analysis of mixtures has been used extensively for a variety of applications ranging from the analysis of plant extracts, wine, and food to the evaluation of toxicity in animals. For example, NMR analysis of urine samples has been used extensively for biomarker discovery and, more simply, for the construction of classification models of toxicity, disease, and biochemical phenotype. However, NMR spectra of complex mixtures typically show unwanted local peak shifts caused by matrix and instrument variability, which must be compensated for prior to statistical analysis and interpretation of the data. One approach is to align the spectral peaks across the data set. An efficient and fast warping algorithm is required as the signals typically contain ca. 32,000-64,000 data points and there can be several thousand spectra in a data set. As demonstrated in our study, the iterative fuzzy warping algorithm fulfills these requirements and can be used on-line for an alignment of the NMR spectra. Correlation coefficients between the aligned and target spectra are used as the evaluation function for the algorithm, and its performance is compared with those of other published warping methods.     

Multidimensional custom-made non-linear microscope: from ex-vivo to in-vivo imaging

We have built a custom-made multidimensional non-linear microscope equipped with a combination of several non-linear laser imaging techniques involving fluorescence lifetime, multispectral two-photon and second-harmonic generation imaging. The optical system was mounted on a vertical honeycomb breadboard in an upright configuration, using two galvo-mirrors relayed by two spherical mirrors as scanners. A double detection system working in non-descanning mode has allowed both photon counting and a proportional regime. This experimental setup offering high spatial (micrometric) and temporal (sub-nanosecond) resolution has been used to image both ex-vivo and in-vivo biological samples, including cells, tissues, and living animals. Multidimensional imaging was used to spectroscopically characterize human skin lesions, as malignant melanoma and naevi. Moreover, two-color detection of two photon excited fluorescence was applied to in-vivo imaging of living mice intact neocortex, as well as to induce neuronal microlesions by femtosecond laser burning. The presented applications demonstrate the capability of the instrument to be used in a wide range of biological and biomedical studies. PACS  87.64.mn; 78.47.Cd; 87.19.lw     

Expanded Analogs of Three-Dimensional Lead-Halide Hybrid Perovskites

Replacing the Pb−X octahedral building unit of A^IPbX₃ perovskites (X=halide) with a pair of edge-sharing Pb−X octahedra affords the expanded perovskite analogs: A^IIPb₂X₆. We report seven members of this new family of materials. In 3D hybrid perovskites, orbitals from the organic molecules do not participate in the band edges. In contrast, the more spacious inorganic sublattice of the expanded analogs accommodates larger pyrazinium-based cations with low-lying π* orbitals that form the conduction band, substantially decreasing the band gap of the expanded lattice. The molecular nature of the conduction band allows us to electronically dope the materials by reducing the organic molecules. By synthesizing derivatives with A^II=pyridinium and ammonium, we can isolate the contributions of the pyrazinium-based orbitals in the band gap transition of A^IIPb₂X₆. The organic-molecule-based conduction band and the inorganic-ion-based valence band provide an unusual electronic platform with localized states for electrons and more disperse bands for holes upon optical or thermal excitation.