Isomorphic A-Site Substitution on Sillenite-Type Compounds

Investigations of A-site substitution in sillenite-type compounds showed that only a substituent ion with a lone-electron pair can be successfully incorporated onto the A-site in place of Bi³⁺. This is because the stability of sillenite structural polyhedra is conditioned by the presence of a stereochemically active lone-electron pair. Accordingly, the substitutional experiments combined with an X-ray diffraction analysis, energy- and wavelength-dispersive microanalysis, and Rietveld refinement showed that Nd³⁺ and La³⁺ ions, which do not possess a lone-electron pair, cannot be incorporated into the sillenite-type structure above the detection limits of the applied analytical techniques. In contrast, the A-site substitution of Pb²⁺, Tl⁺, and Sb³⁺ ions, which do possess a lone-electron pair, was experimentally confirmed. Te⁴⁺ also possesses a lone-electron pair, but the substitutional experiments showed that this ion did not incorporate into the sillenite structure.     

Ultrasonic Evaluation of Initiation and Development of Oxidation Damage in Ceramic-Matrix Composites

In this paper we report on the development of a method for ultrasonic nondestructive characterization of oxidation damage in ceramic-matrix composites. The method is based on ultrasonic measurement of elastic moduli of the composite, which are then used to determine the elastic moduli of the fiber-matrix interphase. Thus the interphasial damage may be estimated quantitatively. As a model system we used, to demonstrate applicability of the method, a unidirectional SiC-fiber-reinforced reaction-bonded silicon nitride matrix composite (SiC/RBSN). The composite samples were oxidized in flowing oxygen for 0.1, 1, 10, and 100 h at 600°, 900°, 1200°, and 1400°C. The ultrasonic phase velocity in the composite was measured at room temperature before and after oxidation; the data were then used to find the composite moduli, which quantify the induced damage. Significant changes in ultrasonic velocities and composite moduli were found as a result of oxidation. Fiber-matrix interphasial moduli were determined by multiphase micromechanical analysis. We found that oxidation of the carbon interphasial layer is the dominant mechanism in decreasing the elastic moduli of the composite. The critical exposure time for transition from the nondamaged to the damaged state at different oxidation temperatures has been determined.     

Slowly on,Slowly off: Bisubstrate‐Analogue Conjugates of 5‐Iodotubercidin and Histone H3 Peptide Targeting Protein Kinase Haspin

The atypical protein kinase haspin is a key player in mitosis by catalysing the phosphorylation of Thr3 in histone H3, and thus ensuring the normal function of the chromosomal passenger complex. Here, we report the development of bisubstrate‐analogue inhibitors targeting haspin. The compounds were constructed by linking 5‐iodotubercidin to the N terminus of histone H3 peptide. The new conjugates show high affinity (sub‐nanomolar K_D) towards haspin as well as slow kinetics of association and dissociation (residence time of several hours). This reflects a unique binding mode and translated into improved selectivity. The latter was confirmed in a biochemical binding/displacement assay with a panel of ten protein kinases, in a thermal shift assay with off‐targets of 5‐iodotubercidin (adenosine kinase and the Cdc2‐like kinase family) and in assay with spiked HeLa cell lysate.     

Peptide‐Enhanced Selective Surface Deposition of Polymer‐Based Fragrance Delivery Systems

Surface deposition is a critical step in the application of fragrance‐containing products. This contribution presents a novel strategy to enhance the deposition of polymer‐based fragrance delivery systems onto cotton substrates from the application medium using phage display identified peptides. Following the identification of cotton binding peptide ligands under fabric softening conditions via phage display, the strongest binding peptide ligand is incorporated into two model polymer‐based fragrance delivery systems, viz., polymer profragrances and polymer nanoparticles. The model polymer profragrance used is a linear, water soluble poly(N‐(2‐hydroxypropyl)methacrylamide) conjugate, while poly(styrene‐co‐acrylic acid) (PS‐co‐PAA) nanoparticles prepared via miniemulsion polymerization are chosen as the second model system. The incorporation of the cotton binding peptide ligand into these fragrance delivery systems enhances their surface deposition two‐ to three‐fold, as evidenced by fluorescence intensity measurements. In the case of the fragrance‐containing PS‐co‐PAA nanoparticles, the enhanced surface deposition also translates into an increased fragrance release from the cotton surface according to dynamic headspace sampling measurements.     

Metabolome-Driven Regulation of Adenovirus-Induced Cell Death

A viral infection that involves virus invasion, protein synthesis, and virion assembly is typically accompanied by sharp fluctuations in the intracellular levels of metabolites. Under certain conditions, dramatic metabolic shifts can result in various types of cell death. Here, we review different types of adenovirus-induced cell death associated with changes in metabolic profiles of the infected cells. As evidenced by experimental data, in most cases changes in the metabolome precede cell death rather than represent its consequence. In our previous study, the induction of autophagic cell death was observed following adenovirus-mediated lactate production, acetyl-CoA accumulation, and ATP release, while apoptosis was demonstrated to be modulated by alterations in acetate and asparagine metabolism. On the other hand, adenovirus-induced ROS production and ATP depletion were demonstrated to play a significant role in the process of necrotic cell death. Interestingly, the accumulation of ceramide compounds was found to contribute to the induction of all the three types of cell death mentioned above. Eventually, the characterization of metabolite analysis could help in uncovering the molecular mechanism of adenovirus-mediated cell death induction and contribute to the development of efficacious oncolytic adenoviral vectors.     

Rational representations of behaviors: Interconnectability and stabilizability

This paper presents an analysis of representation and stability properties of dynamical systems whose signals are assumed to be square summable sequences. Systems are defined as families of trajectories with no more structure than linearity and shift invariance. We depart from the usual input-output and operator theoretic setting and view relationships among system variables as a more general starting point for the study of dynamical systems. Parametrizations of two model classes are derived in terms of analytic functions which define kernel and image representations of dynamical systems. It is shown how state space models are derived from these representations. Uniqueness and minimality of these representations are completely characterized. Elementary properties like stabilizability, regularity, and interconnectability of dynamical systems are introduced and characterized in this set theoretic framework.Part of this research has been made possible by a grant from the European Community for the Systems Identification and Modeling Network (SIMONET).This research has been made possible by a fellowship of the Royal Netherlands Academy of Sciences and Arts.     

The effect of structural properties of natural silica precursors in the mesoporogen-free synthesis of hierarchical ZSM-5 below 100 °C

The low-temperature synthesis of zeolite ZSM-5 below 100 °C is gaining new attention. This is due to the fact that such synthesis may simultaneously implement the introduction of mesopores into crystalline microporous zeolite structure. Herein, we report the use of natural silica precursors from rice husks in the mesoporogen-free synthesis of hierarchical ZSM-5 below 100 °C and their structural properties which govern the course of crystallization. Rice husks are agricultural wastes with high silica content, which should be exploited to give a positive impact, i.e. highly value-added materials. In this study, the amorphous silica from rice husks was extracted using sequential base-acid treatment. The extracted silica was similarly reactive as Ludox HS-40, even with the reduced amounts of the organic structure-directing agent (OSDA). The product was highly crystalline ZSM-5 with spherical morphology composed of small crystallites, enabling the presence of intercrystallite mesopores. The subjection of extracted silica into the calcination at 550 °C for 6 h, prior to the low-temperature synthesis, altered the silica structure via hydroxyl condensation. The distinct structural properties affected the occurring crystallization in which the resulted products were ZSM-5–disordered-mesoporous silica composites. The possible mechanisms of these two different results may involve the dual roles of tetrapropylammonium ion (TPA⁺) as zeolite OSDA and non-templating structure directing agent. These insights were based on the spectroscopic (FTIR, Raman, ²⁹Si and ²⁷Al MAS NMR spectroscopy), microscopic (TEM and HRTEM) and physicochemical characterizations (XRD and N₂ adsorption-desorption isotherm).     

Engineering Chemically Active Defects in Monolayer MoS2 Transistors via Ion‐Beam Irradiation and Their Healing via Vapor Deposition of Alkanethiols

Irradiation of 2D sheets of transition metal dichalcogenides with ion beams has emerged as an effective approach to engineer chemically active defects in 2D materials. In this context, argon‐ion bombardment has been utilized to introduce sulfur vacancies in monolayer molybdenum disulfide (MoS₂). However, a detailed understanding of the effects of generated defects on the functional properties of 2D MoS₂ is still lacking. In this work, the correlation between critical electronic device parameters and the density of sulfur vacancies is systematically investigated through the fabrication and characterization of back‐gated monolayer MoS₂ field‐effect transistors (FETs) exposed to a variable fluence of low‐energy argon ions. The electrical properties of pristine and ion‐irradiated FETs can be largely improved/recovered by exposing the devices to vapors of short linear thiolated molecules. Such a solvent‐free chemical treatment—carried out strictly under inert atmosphere—rules out secondary healing effects induced by oxygen or oxygen‐containing molecules. The results provide a guideline to design monolayer MoS₂ optoelectronic devices with a controlled density of sulfur vacancies, which can be further exploited to introduce ad hoc molecular functionalities by means of thiol chemistry approaches.     

Design assessment of a multiple passenger vehicle component using load transfer index ($$ {\text{U}}^{*} $$) method

In recent years, the study of the load transfer in the structure has achieved a growing attention from mechanical engineers, specifically in the vehicle industry. To further develop this relatively new branch of structural analysis and in particular the \( {\text{U}}^{*} \) index theory for load transfer analysis, it seems necessary to apply this method to different vehicle components. Therefore, in this study, one of the main load carrying components of a multiple passengers carrying vehicle was chosen for load transfer analysis. This choice has significant importance due to the focus of previous \( {\text{U}}^{*} \) index studies on small passenger vehicles, which have completely different structure and load paths. Another important feature of this study is the application of a sophisticated and detailed approach for choosing the loading and boundary condition. To address an actual working condition, a full model of the vehicle was analyzed under different working loads and the most severe loading condition was selected for this study. Then, a detailed \( {\text{U}}^{*} \) index analysis was performed on the structure to evaluate the load transfer for both loading and reaction forces. Based on the results of this analysis, parts with questionable stiffness were located and a design modification was proposed to improve the structural behavior. In addition, to verify the computer model and conclusions of the \( {\text{U}}^{*} \) index analysis, the structure was tested physically under same loading condition. Finally, the proposed modified design of the structure was analyzed with \( {\text{U}}^{*} \) index theory, and using the design criteria suggested in the theory, it was shown that the new design has great potential for better performance and more efficient load transfer.     

#Psychology: a bibliometric analysis of psychological literature in the online media

Online media and especially social media are becoming more and more relevant to our everyday life. Reflecting this tendency in the scientific community, alternative metrics for measuring scholarly impact on the web are increasingly proposed, extending (or even replacing) traditional metrics (e.g., citations, journal impact factor, etc.). This paper explores the relationship between traditional metrics and alternative metrics for psychological research in the years from 2010 to 2012. Traditional publication metrics (e.g., number of citations, impact factor) and alternative metrics (collected from Altmetric, a website that collects and counts references as they appear in Wikipedia, public policy documents, research blogs, mainstream media, or social networks) were extracted and compared, using a dataset of over 245,000 publications from the Web of Science. Results show positive, small to medium, correlations on the level of individual publications, and frequently medium to high correlations on the level of research fields of Psychology. The more accumulated the level of analysis, the higher the correlations. These findings are fairly robust over time and comparable to findings from research areas other than Psychology. Additionally, a new metric, the Score Factor, is proposed as a useful alternative metric to assess a journal’s impact in the online media.