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Generation of well-defined organic-inorganic hybrid materials with controllable size and morphology is challenging and an active area of modern research in view of their unique properties and thus multifunctional applications. Specifically polyoxometalates (POMs) were recognized as a very promising group for the construction of those systems, nonetheless there are domains where the profound understanding of hierarchical mutual interactions and assembly are lacking. We present an efficient approach towards the synthesis of a novel group of POM-based nanocomposites that we name Complex-Decorated Surfactant Encapsulated-Clusters (CD-SECs). In the investigated system the organic surfactant may behave as a metal-coordinating agent, thus allowing for derivatization of the synthesized SECs via utilization of the non-covalent interactions. We demonstrate possibilities and limitations of three types of hybrid systems (H1-H3) generated via seven distinct constructing approaches (routes A-G). These systems have the potential to exhibit multiresponsive functions depending on the nature of their building blocks and could find many potential applications in biology or materials science.

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BACKGROUND: Less invasive alternatives to optical colonoscopy (OC) may improve patient compliance with investigation, but study of patient preference is limited. OBJECTIVES: The aims of this study were to determine patient tolerance and acceptability of OC, computed tomography colonography (CTC) and colon capsule endoscopy (CCE) and also to determine the choice of investigation made by fully informed members of the lay public. PATIENTS AND METHODS: Patients assigned a Gloucester Comfort Score (GCS, 1-5; as did endoscopists), an overall test experience score (visual analogue scale, 0-10) and completed a 'Friends and Family Test' following OC, CTC or CCE. In the second part of the study, members of the public were given information detailing the nature, tolerance, acceptability, risks and outcomes and invited to choose which test they would prefer in the event that one was needed. RESULTS: Assessed by endoscopist and patient, respectively, 24.2 and 49.3% (P<0.005) of symptomatic and 27.3 and 22.1% (P=0.4) of Bowel Cancer Screening Programme patients suffered moderate to severe discomfort (GCS: 4-5) [GCS (mean±SEM): 3.32±0.085, 1.96±0.083 and 1.30±0.088 (P<0.001); overall experience: 5.43, 2.35 and 3.80 (P<0.001)]. In all, 93.6, 96.1 and 85.7% of OC, CTC and CCE patients, respectively, were willing to undergo the same test under the same circumstances. The lay public (n=100) chose a noninvasive test (CTC or CCE) in 55% of the cases to investigate symptoms and chose a Bowel Cancer Screening Programme test in 29% of the cases (P<0.001). CONCLUSION: Patient tolerance and experience favours CTC and CCE over OC and informed about all aspects of each procedure; a noninvasive option is commonly chosen by the lay public.

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A linear-scaling implementation of the elongation cutoff technique (ELG/C) that speeds up Hartree-Fock (HF) self-consistent field calculations is presented. The cutoff method avoids the known bottleneck of the conventional HF scheme, that is, diagonalization, because it operates within the low dimension subspace of the whole atomic orbital space. The efficiency of ELG/C is illustrated for two model systems. The obtained results indicate that the ELG/C is a very efficient sparse matrix algebra scheme.

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The elongation cutoff technique at restricted Hartree-Fock (HF) level of theory in conventional type of calculations, i.e., with two electron integrals (TEI) stored on a disc, is presented for two model systems. It is demonstrated that the number of TEI in the elongation cutoff calculations increases linearly with the system size thus, allowing to extend the conventional type of calculations to bigger systems. The step CPU (central processing unit) time in the elongation cutoff calculations is much lower than in the HF reference calculations. Such behavior reduces significantly the prefactor in the quadratic scaling relation. The total CPU time in the elongation calculation is about 40% lower than in the conventional HF calculations or comparable to direct type of calculations with the quantum fast multipoles method employed. It is shown that by introducing the interaction radius one can obtain linear scaling in the SCF calculations. Figure: The structure of density matrix and total CPU timings for polyglycine clusters in the elongation cutoff calculations.

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An improved method for peptide sequencing based on acetylation/deuteroacetylation in conjunction with ESI MS is introduced. Derivatization with a 1:1 mixture of acetic anhydride and deuterated acetic anhydride incorporates a stable isotope label into the analyzed molecule. This approach has been initially applied to FAB. Using MS/MS, the technique provides a fast, highly sensitive and reliable determination of the primary structure of unknown peptides. This procedure labels N-terminal fragments formed during MS/MS analysis, resulting in a simplification and faster interpretation of the spectra. The performance of the method has been tested with several synthetic peptides and applied to an efficient sequencing of the peptide map, using a nano-scale LC coupled on-line to a tandem mass spectrometer.

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