FAIR and scalable management of small-angle X-ray scattering data.

A modular research data management toolbox based on the programming language Python, the widely used computing platform Jupyter Notebook, the standardized data exchange format for analytical data (AnIML) and the generic repository Dataverse has been established and applied to analyze small-angle X-ray scattering (SAXS) data according to the FAIR data principles (findable, accessible, interoperable and reusable). The SAS-tools library is a community-driven effort to develop tools for data acquisition, analysis, visualization and publishing of SAXS data. Metadata from the experiment and the results of data analysis are stored as an AnIML document using the novel Python-native pyAnIML API. The AnIML document, measured raw data and plots resulting from the analysis are combined into an archive in OMEX format and uploaded to Dataverse using the novel easyDataverse API, which makes each data set accessible via a unique DOI and searchable via a structured metadata block. SAS-tools is applied to study the effects of alkyl chain length and counterions on the phase diagrams of alkyltrimethyl-ammonium surfactants in order to demonstrate the feasibility and usefulness of a scalable data management workflow for experiments in physical chemistry.

Influence of the Template Removal Method on the Mechanical Stability of SBA-15.

Removing the template from the pores after the polycondensation of the silica precursor is a necessary step in the synthesis of mesoporous silica materials. In our previous work, we developed a method for the efficient and spatially controlled functionalization of SBA-15. First, the silanol groups on the particle surface and in the pore entrances were passivated. After extraction of the template, a pretreatment step in N2 converted the silanol groups to the single and geminal state. Afterwards, an azide functionality was introduced exclusively into the mesopores. This ensured that the catalyst could afterwards be immobilized unambiguously in the mesopores. The mechanical stability of a material functionalized in such a spatially controlled manner is studied and compared to other template removal methods. Even though several studies investigated the influence of the calcination temperature, the presence or the absence of oxygen during the template removal, the specific conditions used during the herein reported selective functionalization procedure have not been covered yet.

The effects of a music intervention during port catheter placement on anxiety and stress.

Studies have shown that perioperative music interventions can reduce patients' anxiety levels. However, in small operations like port catheter surgery evidence is sparse. The present single-blinded, randomised controlled two-armed study included 84 female patients undergoing port catheter placement who were randomly assigned to either listening to music during surgery vs. no music intervention. The medical staff was blind to group allocation. On the day of the surgery anxiety and stress levels were evaluated using subjective (STAI questionnaire, visual analogue scales) and objective (vital parameters, salivary cortisol) parameters at different time points (before the surgery, at the end of the surgery and 1 h post-surgery). The music group showed significant reductions of systolic blood pressure (from 136.5 mmHg ± 26.1 to 123.3 mmHg ± 22.0, p = .002) and heart rate (from 75.6 bpm ± 12.3 to 73.1 bpm ± 12.2, p = .035) from beginning of the surgery to skin suture, whereas the control group did not. No significant effects of the music intervention on subjective anxiety measures or salivary cortisol were revealed. In sum, the study demonstrates that a music intervention during port catheter placement positively influences physiological anxiety levels, whereas no effects were revealed for subjective anxiety and salivary cortisol. Thus, music can be considered as a low cost addition in clinical routine in order to reduce patients' heart rate and blood pressure. Future studies are encouraged to further explore the differential effects of intraoperative music interventions on physiological, endocrinological and subjective anxiety levels.

Mechanisms and Intermediates in the True Liquid Crystal Templating Synthesis of Mesoporous Silica Materials.

Mesoporous silica materials (MSMs) produced by true liquid crystal templating (TLCT) are often considered as direct inverted replicas of the initial lyotropic liquid crystal (LLC) phase. However, the predictive design of tailor-made MSMs requires the full knowledge of the TLCT process, which is still incomplete. Here, we tackle this issue by monitoring the structural evolution during the templating process by small-angle X-ray scattering, showing that after the addition of the silica source the reaction mixture is first isotropic and then an intermediary liquid crystal phase appears, which is the key to the success of the templating process, namely the formation of ordered MSMs. We analyze the structure and the formation dynamics of this intermediary phase and present a simple theoretical model, which allows us to connect the structural parameters of the initial LLC and the MSM. These results provide an enhanced understanding of the TLCT process and are an important step toward the predictable synthesis of new MSMs in the future.

Self-Assembly and Fluorescence of Tetracationic Liquid Crystalline Tetraphenylethene.

A series of tetraguanidinium tetraphenylethene (TPE) arylsulfonates with different chain lengths was prepared via ionic self-assembly of tetraguanidinium TPE chloride and the respective methyl arylsulfonates. Liquid crystalline properties were studied by differential scanning calorimetry, polarizing optical microscopy and X-ray diffraction. Tetraguanidinium TPE arylsulfonates with chain lengths of C8 -C12 displayed hexagonal columnar mesophases over a broad temperature range, while derivatives with longer chains showed oblique columnar phases. In solution all compounds displayed aggregation-induced emission behaviour. Temperature-dependent luminescence spectra of the bulk phase of the tetraguanidinium TPE arylsulfonate with C14 side chains revealed a strong luminescence both in the solid state and the oblique columnar mesophase. The emission behaviour was rationalized by a unique combination of restriction of intramolecular rotation of the TPE core, Coulomb interaction between the guanidinium cations and π-π interactions of the anionic arylsulfonate moieties.

Enhancing Self-Assembly in Cellulose Nanocrystal Suspensions Using High-Permittivity Solvents.

Helical liquid crystal self-assembly in suspensions of cellulose nanocrystals (CNCs), bioderived nanorods exhibiting excellent mechanical and optical properties, opens attractive routes to sustainable production of advanced functional materials. For convenience, in most studies until now, the CNCs were suspended in water, leaving a knowledge gap concerning the influence of the solvent. Using a novel approach for aggregation-free solvent exchange in CNC suspensions, here we show that protic solvents with a high dielectric permittivity εr significantly speed up self-assembly (from days to hours) at high CNC mass fraction and reduce the concentration dependence of the helix period (variation reducing from more than 30 µm to less than 1 µm). Moreover, our computer simulations indicate that the degree of order at constant CNC content increases with increasing εr, leading to a shorter pitch and a reduced threshold for liquid crystallinity. In low-εr solvents, the onset of long-range orientational order is coupled to kinetic arrest, preventing the formation of a helical superstructure. Our results show that the choice of solvent is a powerful parameter for tuning the behavior of CNC suspensions, enhancing our ability to control the self-assembly and thereby harvesting valuable novel cellulose-based materials.

Origin of the Director Tilt in the Lyotropic Smectic†C* Analog Phase: Hydration Interactions and Solvent Variations.

The origin and long-range correlation of the director tilt in the recently discovered Lα'* phase, which is the lyotropic analog of the thermotropic smectic C* (SmC*) liquid crystalline phase, are investigated. Polarized micro-Raman spectroscopy reveals that the director tilt in the Lα'* phase originates from a tilting of the aromatic 2-phenylpyrimidine cores of the surfactant molecules. Optical measurements of the tilt angle show that its magnitude decreases with increasing solvent concentration, suggesting that the long-range inter-lamellar correlation of the tilt directions is reduced at increasing thickness of the solvent layers. The phase diagrams with four different solvents (water, formamide, N-methylformamide, N,N-dimethylformamide) are investigated, showing that the Lα'* phase is only formed with those solvents that exhibit a dense network of hydrogen bonds. This observation suggests that these hydrogen bond networks play an essential role in the long-range correlation of the director tilt between adjacent surfactant layers. To verify this assumption, mixtures with deuterated solvents are investigated, showing that the tilt angle in the Lα'* phase is indeed reduced by this modification of the solvent's hydrogen bond network.

Drawing and handedness of preschoolers: a repeated-measurement approach to hand preference.

This study investigated handedness and drawing by preschoolers. An observational method for repeated measurement of hand preference is presented. A sample of 381 children (191 girls, 190 boys) ranging in age from 48 to 71 mo. was tested for drawing and hand preference on 14 tasks. Consistent hand preference was defined as always using a particular hand (left or right) for the same task. Girls with consistent hand preference showed better drawing scores compared to girls with inconsistent hand preference. The results showed the importance of a reliable method for measuring hand preference within a single task as early as preschool age.