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The photochemical behavior of four arylidenoxindole derivatives are examined in the context of the solid-state reactivity of (hetero)arylidenoxindoles. Data indicate that the photochemistry is quite structure-dependent and has a bearing on the mechanism of solid-state photodimerization.

Noninvasive prenatal testing (NIPT) consists of determining fetal aneuploidies by quantifying copy number alteration from the sequencing of cell-free DNA (cfDNA) from maternal blood. Due to the presence of cfDNA of fetal origin in maternal blood, in silico approaches have been developed to accurately predict fetal aneuploidies. Although NIPT is becoming a new standard in prenatal screening of chromosomal abnormalities, there are no integrated pipelines available to allow rapid, accurate and standardized data analysis in any clinical setting. Several tools have been developed, however often optimized only for research purposes or requiring enormous amount of retrospective data, making hard their implementation in a clinical context. Furthermore, no guidelines have been provided on how to accomplish each step of the data analysis to achieve reliable results. Finally, there is no integrated pipeline to perform all steps of NIPT analysis. To address these needs, we tested several tools for performing NIPT data analysis. We provide extensive benchmark of tools performances but also guidelines for running them. We selected the best performing tools that we benchmarked and gathered them in a computational pipeline. NiPTUNE is an open source python package that includes methods for fetal fraction estimation, a novel method for accurate gender prediction, a principal component analysis based strategy for quality control and fetal aneuploidies prediction. NiPTUNE is constituted by seven modules allowing the user to run the entire pipeline or each module independently. Using two cohorts composed by 1439 samples with 31 confirmed aneuploidies, we demonstrated that NiPTUNE is a valuable resource for NIPT analysis. [ABSTRACT FROM AUTHOR]

The article presents a study which develops a theory to identify the kinematic diffraction response to a periodic perturbation of a crystal. It shows that the diffracted signal doubles the function of the stimulation frequency when a part of a local electron density varies linearly with an external stimulus. It discusses two ways of filtering, demodulation and correlation, with respect to extracting information from the experiment.

The heating process (30–200 °C) of a palygorskite-indigo mixture has been monitored in situ and simultaneously by synchrotron powder diffraction and Raman spectroscopy. During this process, the dye and the clay interact to form Maya blue (MB), a pigment highly resistant to degradation. It is shown that the formation of a very stable pigment occurs in the 70–130 °C interval; i.e., when palygorskite starts to loose zeolitic water, and is accompanied by a reduction of the crystallographic a parameter, as well as by alterations in the C=C and C=O bonds of indigo. Mid- and near-infrared spectroscopic work and microporosity measurements, employed to study the rehydration process after the complex formation, provide evidence for the inhibition of the rehydration of MB as compared with palygorskite. These results are consistent with the blocking of the palygorskite tunnel entrance by indigo molecules with a possible partial penetration inside the tunnels. The surface silanols of palygorskite are not perturbed by indigo, suggesting that MB is not a surface complex. [ABSTRACT FROM AUTHOR]

This paper proposes a decentralized, distributed and secure communication infrastructure for indexing and retrieving multimedia contents with associated digital rights. The lack of structured metadata describing the enormous amount of multimedia contents distributed on the the web leads to simple search mechanisms that usually arc limited to queries by title or by author. Our approach is based on structured peer-to-peer networks and allows complex queries using standard MPEG-7 and MPEG-21 multimedia metadata. Moreover, security aspects limit the development of general purpose real applications using a peer-to-peer routing infrastructure for sharing digital items with an associated license. Accordingly, we propose a framework made up of a secure Distributed Hash Table layer based on Kademlia, including an identity based scheme and a secure communication protocol, providing an effective defense against well known attacks. [ABSTRACT FROM AUTHOR]

Abstract: The structure of the [Os(bpy)2(CO)Cl]+Otf– complex (where bpy=2,2′-bipyridine and Otf– =triflate, CF3SO3 –) has been solved by single crystal X-ray diffraction analysis and the NMR technique has been employed for the characterization of the complex in solution. Theoretical calculations have been performed to unravel the structural disorder found in the solid state and for the characterization of the geometric and energetic features of the complex in apolar solution. This study is part of our investigation of Os(bpy)2(CO) complexes and in this paper we also intend to investigate the effect of different anions on the solid and solution properties of the [Os(bpy)2(CO)Cl]+ cation. To cite this article: G. Croce et al., C. R. Chimie 8 (2005) . [Copyright &y& Elsevier]

Multivariate analysis (MA) is becoming a fundamental tool for processing in an efficient way the large amount of data collected in X-ray diffraction experiments. Multi-wedge data collections can increase the data quality in case of tiny protein crystals; in situ or operando setups allow investigating changes on powder samples occurring during repeated fast measurements; pump and probe experiments at X-ray free-electron laser (XFEL) sources supply structural characterization of fast photo-excitation processes. In all these cases, MA can facilitate the extraction of relevant information hidden in data, disclosing the possibility of automatic data processing even in absence of a priori structural knowledge. MA methods recently used in the field of X-ray diffraction are here reviewed and described, giving hints about theoretical background and possible applications. The use of MA in the framework of the modulated enhanced diffraction technique is described in detail. [ABSTRACT FROM AUTHOR]

Plasticized–Poly(vinyl chloride) (P-PVC) for cables and insulation requires performances related to outdoor, indoor and submarine contexts and reduction of noxious release of HCl-containing fumes in case of thermal degradation or fire. Introducing suitable nanomaterials in polymer-based nanocomposites can be an answer to this clue. In this work, an industry-compliant cable-grade P-PVC formulation was added with nanostructured materials belonging to the family of Polyhedral Oligomeric Silsesquioxane (POSS). The effects of the nanomaterials, alone and in synergy with HCl scavenging agents as zeolites and hydrotalcites, on the thermal stability and HCl evolution of P-PVC were deeply investigated by thermogravimetric analysis and reference ASTM methods. Moreover, hardness and mechanical properties were studied in order to highlight the effects of these additives in the perspective of final industrial uses. The data demonstrated relevant improvements in the thermal stability of the samples added with nanomaterials, already with concentrations of POSS down to 0.31 phr and interesting additive effects of POSS with zeolites and hydrotalcites for HCl release reduction without losing mechanical performances. [ABSTRACT FROM AUTHOR]

The title compound, 1-(2′,3′-di­deoxy-β- d- glycero-pent-2-eno­furan­osyl)­thymine 1-methyl-2-pyrrolidone solvate, C10H12N2O4·­C5H9NO, is an NMPO solvate of the anti-AIDS agent D4T. In its crystal structure, both the pyrimidine and the furan­ose rings are planar and approximately perpendicular [82.1 (4)°]. The value of the torsion angle defining the orientation of the thymine with respect to the joined furane, χ = −100.8 (4)°, and that of the torsion angle giving the orientation of the hydroxyl group linked to the furane ring, γ = 52.9 (5)°, show that the gly­cosyl­ic link adopts the so-called high- anti conformation and the 5′-hydroxyl group is in the + sc position. The NMPO solvate is linked to the nucleoside through a fairly strong hydrogen bond. [ABSTRACT FROM AUTHOR]