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Recent advances in alkaline earth (Ae) metal hydrogenation catalysis have broadened the spectrum of potential catalysts to include candidates from the main group, providing a sustainable alternative to the commonly used transition metals. Although Ae-amides have already been demonstrated to catalyze hydrogenation of imines and alkenes, a lucid understanding of how different metal/ligand combinations influence the catalytic activity is yet to be established. In this article, we use linear scaling relationships and molecular volcano plots to assess the potential of the Ae metal-based catalysts for the hydrogenation of alkenes. By analyzing combinations of eight metals (mono-, bi-, tri-, and tetravalent) and seven ligands, we delineate the impact of metal-ligand interplay on the hydrogenation activity. Our findings highlight that the catalytic activity is majorly determined by the charge and the size of the metal ions. While bivalent Ae metal cations delicately regulate the binding and the release of the reactants and the products, respectively, providing the right balance for this reaction, ligands play only a minor role in determining their catalytic activity. We show how volcano plots can be utilized for the rapid screening of prospective Ae catalysts to establish a guideline to achieve maximum activity in facilitating the hydrogenation process. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate medium-term clinical outcomes with microstent XEN® 45 Gel Stent (Allergan Dublin, Ireland) for treatment of primary open-angle glaucoma (POAG). Material and methods: This is a retrospective, descriptive and observational study involving 93 eyes from 63 patients who had undergone POAG surgery with a XEN® 45 Gel Stent implantation and had been followed up and controlled between 12 and 36 months. Results: IOP dropped from 18.23 ± 5.00 mmHg pre-op to 14.16 ± 2.14, 14.47 ± 2.16 and 14.63 ± 1.91 at 1, 2 and 3 years after surgery (p = 0.000, 0.000 and 0.001) consecutively. Mean number of medications dropped from 1.87 ± 0.94 preoperatively to 0.31 ± 0.69, 0.34 ± 0.63 and 1.00 ± 0.88 (p = 0.000, 0.000 and 0.017) at 12, 24 and 36 months. Mean visual field deviation values never turned out to be significant for any of the follow-up visit data. A total of 94.6% of the surgical procedures turned out to be complication-free. In one surgery, the procedure failed and 18 months later other device was implanted. Conclusion: POAG surgical procedures with XEN® 45 Gel Stent implants are a safe and effective treatment approach. [ABSTRACT FROM AUTHOR]

Describing non-covalent interactions (NCIs) has shown to be of paramount importance in many areas of theoretical chemistry and related disciplines, such as biochemistry and material science. However, non-covalent interactions are subtle effects, very difficult to reproduce from most common computational approaches. Electron density studies have shown to provide a good semiquantitative visual approach to such interactions, which are much less prone to method dependency. But to which extent? This is the question addressed in this contribution. The NCI approach based on the reduced density gradient is given the third degree so as to provide the user with a benchmark on how it is affected by the computational method and the basis set of choice. We have assessed the dependence of the NCI results on the geometry. This last question is addressed in detail to dissect how, why and when the NCI method can be used to understand dispersion interactions. Along various examples, we will show that the NCI index is very little dependent on the method and basis set used in the calculation of the electron density as long as the geometry is kept fixed. Indeed, the biggest variations in NCI come from changes in the geometry. Thus, methods which provide descriptions of a given interaction type of different accuracies will yield different electron density organizations. This gives no qualitative variations in the NCI 3D picture. But it is reflected in quantitative NCI measures even in very subtle cases. Moreover, in the case of a failure of the calculation method, NCI can also reveal the sources of its error. NCI volumes are able to locate the energetic ordering in various conformational situations, but always in a relative manner. Absolute values should not be used in comparisons, nor between compounds that do not belong to the same family. [ABSTRACT FROM AUTHOR]

We present an optical system that performs polarimetric spectral imaging with a detector with no spatial resolution. This fact is possible by applying the theory of compressive sampling to the data acquired by a sensor composed of an analyzer followed by a commercial fiber spectrometer. The key element in the measurement process is a digital micromirror device, which sequentially generates a set of intensity light patterns to sample the object image. For different configurations of the analyzer, we obtain polarimetric images that provide information about the spatial distribution of light polarization at several spectral channels. Experimental results for colorful objects are presented in a spectral range that covers the visible spectrum and a part of the NIR range. The performance of the proposed technique is discussed in detail, and further improvements are suggested. [ABSTRACT FROM AUTHOR]

Microalgae are the main component of first tropic level in aquatic food chain; it is for this reason that they are used as food in aquaculture. Also due to its biotechnological potential properties, they are used in the production of diverse components, dyes, antioxidants, enzymes, emulsifiers, etc. The extended ways of microalgae applications require physiologically and genetically stable cultures as well as correctly identified organisms to guarantee reproducibility and reliability. But the variety of species and the morphological similarity between some of them make difficult the identification of some microalgae. The use of molecular markers has supplied a very useful tool for identification of microalgae in fast mode, such as in classification. The present study has worked on the molecular characterization of main species of microalgae used in aquaculture in base of the molecular markers 18S rRNA and 16S rRNA. Microalgae DNA has been amplified and sequenced, and the resultant sequences were analyzed and reflected in phylogenetic trees. The phylogenetic analyses obtained reflect as both molecular markers allow to differentiate the main genus used in aquaculture. [ABSTRACT FROM AUTHOR]