Metal-semiconductor hybrid heteronanostructures may exhibit synergistically reinforced optical responses and significantly enhanced optical tunability that essentially arise from the unique nanoscale interactions between the metal and semiconductor components. Elaboration of multi-component hybrid nanoparticles allows us to achieve optimized or diversified material functionalities through precise control over the dimension and morphology of the constituent building units, on one hand, and through engineering their relative geometrical arrangement and interfacial structures, on the other hand. Here we study the geometry-dependent optical characteristics of metal-cuprous oxide (Cu(2)O) core-shell hybrid nanoparticles in great detail through combined experimental and theoretical efforts. We demonstrate that several important geometrical parameters, such as shell thickness, shell crystallinity, shell porosity, and core composition, of the hybrid nanoparticles can be tailored in a highly precise and controllable manner through robust wet chemistry approaches. The tight control over the particle geometries provides unique opportunities for us to develop quantitative understanding of how the dimensions, morphologies, and electronic properties of the semiconducting shells and the geometry and compositions of the metallic cores affect the plasmon resonance frequencies, the light scattering and absorption cross sections, and the overall extinction spectral line shapes of the hybrid nanoparticles. Mie scattering theory calculations provide further insights into the origin of the geometrically tunable optical responses and the interesting extinction spectral line shapes of the hybrid nanoparticles that we have experimentally observed.

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Peanuts are a cause of one of the most common food allergies. Allergy to peanuts not only affects a significant fraction of the population, but it is relatively often associated with strong reactions in sensitized individuals. Peanut and tree nut allergies, which start in childhood are often persistent and continue through life, as opposed to other food allergies that resolve with age. Therefore, peanut allergens are one of the most intensively studied food allergens. In this review we focus on the structural studies of peanut allergens.

The production of macromolecular crystals suitable for structural analysis is one of the most important and limiting steps in the structure determination process. Often, preliminary crystallization trials are performed using hundreds of empirically selected conditions. Carboxylic acids and/or their salts are one of the most popular components of these empirically derived crystallization conditions. Our findings indicate that almost 40 % of entries deposited to the Protein Data Bank (PDB) reporting crystallization conditions contain at least one carboxylic acid. In order to analyze the role of carboxylic acids in macromolecular crystallization, a large-scale analysis of the successful crystallization experiments reported to the PDB was performed. The PDB is currently the largest source of crystallization data, however it is not easily searchable. These complications are due to a combination of a free text format, which is used to capture information on the crystallization experiments, and the inconsistent naming of chemicals used in crystallization experiments. Despite these difficulties, our approach allows for the extraction of over 47,000 crystallization conditions from the PDB. Initially, the selected conditions were investigated to determine which carboxylic acids or their salts are most often present in crystallization solutions. From this group, selected sets of crystallization conditions were analyzed in detail, assessing parameters such as concentration, pH, and precipitant used. Our findings will lead to the design of new crystallization screens focused around carboxylic acids.