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Boron nitride nanotubes (BNNTs) are an emerging class of molecular container offering new functionalities and possibilities for studying molecules at the nanoscale. Herein, BNNTs are demonstrated as highly effective nanocontainers for polyoxometalate (POM) molecules. The encapsulation of POMs within BNNTs occurs spontaneously at room temperature from an aqueous solution, leading to the self-assembly of a POM@BNNT host-guest system. Analysis of the interactions between the host-nanotube and guest-molecule indicate that Lewis acid-base interactions between W═O groups of the POM (base) and B-atoms of the BNNT lattice (acid) likely play a major role in driving POM encapsulation, with photoactivated electron transfer from BNNTs to POMs in solution also contributing to the process. The transparent nature of the BNNT nanocontainer allows extensive investigation of the guest-molecules by photoluminescence, Raman, UV-vis absorption, and EPR spectroscopies. These studies revealed considerable energy and electron transfer processes between BNNTs and POMs, likely mediated via defect energy states of the BNNTs and resulting in the quenching of BNNT photoluminescence at room temperature, the emergence of new photoluminescence emissions at cryogenic temperatures (100 K), a photochromic response, and paramagnetic signals from guest-POMs. These phenomena offer a fresh perspective on host-guest interactions at the nanoscale and open pathways for harvesting the functional properties of these hybrid systems.

The paradigmatic shift from traditional flood defense toward integrated flood risk management has widened the sectors and policies affected and has spurred a growing interest of scholars to understand cross-sectoral flood policy integration. In this paper we argue that the cross-sectoral goal relationship—ranging from complementary to conflictual policy goals—is a useful conceptual framework to understand (1) the policy integration challenge at hands and (2) in particular the unfolding policy integration from a processual perspective. For our empirical analysis we identify three policy subsystems that are highly important for sectoral interplay in flood risk management: agriculture, hydropower generation, and spatial planning. Using Austria as a case study we illustrate the goal relationships and sectoral policy integration challenges in each of these fields of interaction. Based on 45 expert interviews in the selected policy sectors we provide useful insights into the current processes of flood policy integration. The empirical findings from our case studies show that sectoral goal relationships and the nature of the policy integration challenge drive flood policy integration. More pronounced land use conflicts are more strongly reflected in different actor interests, policy frames, policy goals, and the choice of policy instruments. Sectoral goal relationships are an important factor to explain the unfolding policy integration process. Complementary policy goals result in rather informal, harmonious integrative negotiations on strengthening synergies by using soft policy instruments. On the contrary, conflictual policy goals lead to more formal negotiations among the affected sectors relying on hard, regulative instruments.

Density functional theory is the workhorse of materials simulations. Unfortunately, the quality of results often varies depending on the specific choice of the exchange-correlation functional, and this significantly limits the predictive power of this approach. Coupled cluster theory, including single, double and perturbative triple particle-hole excitation operators, is widely considered as the `gold standard` of quantum chemistry as it can achieve chemical accuracy for non-strongly correlated applications. Because of the high computational cost, the application of coupled cluster theory in materials simulations is rare, and this is particularly true if finite-temperature properties are of interest for which molecular dynamics simulations have to be performed. By combining recent progress in machine learning models with low data requirements for energy surfaces and in the implementation of coupled cluster theory for periodic materials, we show that chemically accurate simulations of materials are practical and could soon become significantly widespread. As an example of this numerical approach, we consider the calculation of the enthalpy of adsorption of CO2 in a porous material.

Monolayer transition-metal dichalcogenide (TMD) semiconductors exhibit strong excitonic effects and hold promise for optical and optoelectronic applications. Yet, electron doping of TMDs leads to the conversion of neutral excitons into negative trions, which recombine predominantly non-radiatively at room temperature. As a result, the photoluminescence (PL) intensity is quenched. Here we study the optical and electronic properties of a MoS2/WSe2 heterostructure as a function of chemical doping by Cs atoms performed under ultra-high vacuum conditions. By PL measurements we identify two interlayer excitons and assign them to the momentum-indirect Q-Gamma and K-Gamma transitions. The energies of these excitons are in a very good agreement with ab initio calculations. We find that the Q-Gamma interlayer exciton is robust to the electron doping and is present at room temperature even at a high charge carrier concentration. Submicrometer angle-resolved photoemission spectroscopy (micro-ARPES) reveals charge transfer from deposited Cs adatoms to both the upper MoS2 and the lower WSe2 monolayer without changing the band alignment. This leads to a small (10 meV) energy shift of interlayer excitons. Robustness of the momentum-indirect interlayer exciton to charge doping opens up an opportunity of using TMD heterostructures in light-emitting devices that can work at room temperature at high densities of charge carriers.

Background and aims: High lipoprotein(a) [Lp(a)] concentrations are associated with increased coronary artery disease (CAD) risk. Lp(a) is regulated mainly genetically by the LPA gene but involved genetic variants have not been fully elucidated. Improved understanding of the entanglements of genetic Lp(a) regulation may enhance genetic prediction of Lp(a) and CAD risk. We investigated an interaction between the well-known LPA missense SNP rs41272110 (known as Thr3888Pro) and the frequent LPA splicing mutation KIV-2 4925G>A. Methods: Effects on Lp(a) concentrations were investigated by multiple quantile regression in the German Chronic Kidney Disease (GCKD) study, KORA-F3 and KORA-F4 (ntotal = 10,405) as well as in the UK Biobank (UKB) 200k exome dataset (n = 173,878). The impact of the interaction on CAD risk was assessed by survival analysis in UKB. Results: We observed a significant SNP-SNP interaction in all studies (p = 1.26e-05 to 3.03e-04). In quantile regression analysis, rs41272110 as a predictor shows no impact on Lp(a) (β = −0.06 [-0.79; 0.68], p = 0.879), but in a joint model including both SNPs as predictors, rs41272110 is associated with markedly higher Lp(a) (β = +9.40 mg/dL [6.45; 12.34], p = 4.07e-10). Similarly, rs41272110 shows no effect on CAD in UKB (HR = 1.01 [0.97; 1.04], p = 0.731), while rs41272110 carriers not carrying 4925G>A show an increased CAD risk (HR = 1.10 [1.04; 1.16], p = 6.9e-04). This group corresponds to 4% of the population. Adjustment for apolipoprotein(a) isoforms further modified the effect estimates markedly. Conclusions: This work emphasizes the complexity of the genetic regulation of Lp(a) and the importance to account for genetic subgroups in Lp(a) association studies and when interpreting genetic cardiovascular risk profiles.

Computationally efficient and accurate quantum mechanical approximations to solve the many-electron Schrödinger equation are crucial for computational materials science. Methods such as coupled cluster theory show potential for widespread adoption if computational cost bottlenecks can be removed. For example, extremely dense k-point grids are required to model long-range electronic correlation effects, particularly for metals. Although these grids can be made more effective by averaging calculations over an offset (or twist angle), the resultant cost in time for coupled cluster theory is prohibitive. We show here that a single special twist angle can be found using the transition structure factor, which provides the same benefit as twist averaging with one or two orders of magnitude reduction in computational time. We demonstrate that this not only works for metal systems but also is applicable to a broader range of materials, including insulators and semiconductors.

Precision laser spectroscopy of the 229-thorium nuclear isomer transition in a solid-state environment would represent a significant milestone in the field of metrology, opening the door to the realization of a nuclear clock. Working toward this goal, experimental methods require knowledge of various properties of a large band-gap material, such as calcium fluoride doped with specific isotopes of the heavy elements thorium, actinium, cerium, neptunium, and uranium. By accurately determining the atomic structure of potential charge compensation schemes by using a generalized gradient approximation within the ab-initio framework of density functional theory, calculations of electric field gradients on the dopants become accessible, which cause a quadrupole splitting of the nuclear-level structure that can be probed experimentally. Band gaps and absorption coefficients in the range of the 229-thorium nuclear transition are estimated by using the G0W0 method and by solving the Bethe–Salpeter equation.

Patterns formed in monolayer graphene (Gr) and hexagonal boron nitride (h-BN) upon ion irradiation in the temperature range from 950 to 1530 K using 500 eV He+ at normal or 500 eV Xe+ at grazing incidence and fluences up to 2.5×1019 ions/m2 are investigated by room-temperature scanning tunneling microscopy. Subnanometer pores are created and are distributed with the periodicity of the moiré which results from the interaction of the monolayers with their Ir(111) substrate. The moiŕe contains trapping sites for vacancies within each moiré unit cell as is investigated in detail for the case of h-BN with the help of ab initio calculations. The density of the nanopores is extremely high in the order of 1017 pores/m2 and their size distribution is limited by the size of the vacancy traps causing excess vacancies to be expelled from the array and to anneal at preexistent defects. Successful delamination of a perforated Gr monolayer from the substrate is demonstrated and makes the material accessible for membrane research.

A magnetic field modifies optical properties and provides valley splitting in a molybdenum disulfide (MoS

Periodic structures of silicon are of interest in quantum-dot-based applications because of their unique optical and electronic properties. We report on the fabrication of stable quasi-ordered Si nanocluster arrays on the moiré of a hexagonal boron nitride (h-BN) monolayer on Ir(111). The h-BN monolayer promotes the growth of regular Si nanoclusters at 130 K and electronically decouples the clusters from the underlying metallic substrate. Using scanning tunneling microscopy and spectroscopy, we have investigated the cluster binding sites, their electronic structure, and their thermal stability. We find that the clusters display a size-dependent bandgap and that they are stable up to 577 K, after which cluster coalescence degrades the arrays.

Background: Lp(a) (lipoprotein [a]) is a highly atherogenic lipoprotein strongly associated with coronary artery disease (CAD). Lp(a) concentrations are chiefly determined genetically. Investigation of large pedigrees with extreme Lp(a) using modern whole-genome approaches may unravel the genetic determinants underpinning this pathological phenotype. Methods: A large family characterized by high Lp(a) and increased CAD incidence was recruited by cascade screening. Plasma lipids, lipoproteins, and apolipoproteins concentrations, as well as the size of apo(a) isoforms, were determined enzymatically by high-resolution mass spectrometry and Western blot, respectively. Whole-exome sequencing was performed to search for rare defects in modifier genes. Genetic risk scores (GRS) for Lp(a) and CAD were calculated and their discriminative power was assessed. Results: Seventeen individuals displayed extreme Lp(a) levels including 6 with CAD. Whole-exome sequencing showed no hint for genetic defects outside the LPA locus. The extreme Lp(a) phenotype segregated with the presence of a short apo(a) isoform containing 21 Kringle IV domains. This allele was characterized by the presence of three rare strongly Lp(a) increasing single nucleotide polymorphisms and a significantly increased load of oxidized phospholipids per Lp(a) particle. An Lp(a) GRS consisting of 48 single nucleotide polymorphisms that represent 2001 genome-wide significant LPA single nucleotide polymorphisms, efficiently captured the hyper-Lp(a) phenotype and discriminated affected and nonaffected individuals with great accuracy. The genome-wide GRS for CAD, encompassing 6.6 million single nucleotide polymorphisms, was very high for most family members (>97.5 percentile of the reference population), but this observation was no longer valid when the contribution of the LPA locus was omitted. Conclusions: High-Lp(a) phenotypes can be successfully captured using the Lp(a) GRS even among closely related family members. In hyper-Lp(a) individuals, LPA can be a major locus driving a very high CAD GRS. This underpins the large contribution of the LPA locus to the cardiovascular genetic risk in families.

Das Ziel dieser Arbeit ist, aufzuzeigen, ob die entwickelten Themenboxen einen Beitrag dazu leisten, dass Größen im Mathematikunterricht nachhaltig geübt werden können. Dazu wurde folgende Forschungsfrage gestellt: Wie gut sind Themenboxen für nachhaltiges Üben von Größen im Mathematikunterricht geeignet? Um die Forschungsfrage zu beantworten, wurde eine Erprobung im Unterricht durchgeführt. Dazu wurden zwei Lernstandserhebungen durchgeführt in jeweils einer Treatmentklasse und einer Kontrollklasse einer 5. und 8. Schulstufe, eine vor dem Einsatz der Themenboxen und eine nach dem Einsatz. Um Auskunft darüber zu bekommen, wie ihnen die Arbeit mit den Boxen gefallen hat, wurde von den Lernenden der Treatmentklasse zusätzlich ein Fragebogen ausgefüllt. Der Vergleich der Lernstandserhebungen hat gezeigt, dass die Themenboxen einen Beitrag dazu leisten, dass sich die Leistungen der Schülerinnen und Schüler verbessern. Die Auswertung des Fragebogens hat gezeigt, dass den Lernenden vor allem das regelmäßige Arbeiten an einem Thema, die selbstständige Auswahl der Aufgaben und die Abwechslung zum herkömmlichen Unterricht gut gefallen. Viele Lernenden sind bereits der Meinung, dass sie die Inhalte nun besser können als vorher und sie sich diese nun langfristiger merken können. Auf dieser Grundlage ist es empfehlenswert, Themenboxen gelegentlich im Unterricht einzusetzen, um Themen nachhaltig zu sichern. eingereicht von Carola Grüneis, BEd Angefertigt an der Privaten Pädagogischen Hochschule der Diözese Linz Masterarbeit Universität Linz 2022 Arbeit auf den öffentlichen PCs in den Bibliotheken der JKU+Medizin abrufbar