Glycerol, a primary by-product of biodiesel production, can be oxidized into various value-added chemicals, significantly enhancing the techno-economic value of photoelectrochemical (PEC) cells. Several studies have explored various photoelectrode materials and co-catalysts, but the influence of electrolytes on PEC glycerol oxidation has remained relatively unexplored despite its significance. Here, we explore the impact of various acidic (pH = 2) electrolytes, namely NaNO3, NaClO4, Na2SO4, K2SO4, and KPi, on PEC glycerol oxidation using nanoporous thin film BiVO4 as a model photoanode. Our experimental findings reveal that the choice of electrolyte anion and cation significantly affects the PEC performance (i.e., photocurrent, onset potential, stability, and selectivity towards value-added products) of BiVO4 for glycerol oxidation. To explain this interesting phenomenon, we correlate the observed performance trend with the ion specificity in the Hofmeister series as well as the buffering capacity of the electrolytes. Notably, NaNO3 is identified as the optimal electrolyte for PEC glycerol oxidation with BiVO4 when considering various factors such as stability and production rates for glycerol oxidation reaction (GOR) products, surpassing the previously favored Na2SO4. Glycolaldehyde emerges as the most dominant product with ∼50% selectivity in NaNO3. The general applicability of our findings is confirmed by similar observation in electrochemical (EC) GOR with a polycrystalline platinum anode. Overall, these results emphasize the critical role of electrolyte selection in enhancing the efficiency of EC/PEC glycerol oxidation.
Weniger anzeigenMicroorganisms often live in habitats characterized by fluid flow, and their adhesion to surfaces in industrial systems or clinical settings may lead to pipe clogging, microbially influenced corrosion, material deterioration, food spoilage, infections, and human illness. Here, a novel microfluidic platform was developed to investigate biofilm formation under precisely controlled (i) cell concentration, (ii) temperature, and (iii) flow conditions. The developed platform central unit is a single-channel microfluidic flow cell designed to ensure ultrahomogeneous flow and condition in its central area, where features, e.g., with trapping properties, can be incorporated. In comparison to static and macroflow chamber assays for biofilm studies, microfluidic chips allow in situ monitoring of biofilm formation under various flow regimes and have better environment control and smaller sample requirements. Flow simulations and experiments with fluorescent particles were used to simulate bacteria flow in the platform cell for calculating flow velocity and direction at the microscale level. The combination of flow analysis and fluorescent strain injection in the cell showed that microtraps placed at the center of the channel were efficient in capturing bacteria at determined positions and to study how flow conditions, especially microvortices, can affect biofilm formation. The microfluidic platform exhibited improved performances in terms of homogeneity and robustness for in vitro biofilm formation. We anticipate the presented platform to be suitable for broad, versatile, and high-throughput biofilm studies at the microscale level.
Weniger anzeigenIn the dynamic field of mathematics teacher education, the Journal of Mathematics Teacher Education (JMTE) serves as a vital platform for exploring and advancing the education and professional development of mathematics teachers from an international perspective. This issue of JMTE explores the profound impact of cultural, social and institutional contexts on mathematics teacher education and highlights the diversity of educational experiences that contribute to a global understanding of teaching and learning. By examining the rich and diverse studies presented in this issue, we can appreciate how local insights can be used to contribute to the global discourse on mathematics teacher education.
Weniger anzeigenSupramolecular delivery systems with the prolonged circulation, the potential for diverse functionalization, and few toxin-related limitations have been extensively studied. For the present study, we constructed a linear polyglycerol-shelled polymersome attached with the anti-HER-2-antibody trastuzumab. We then covalently loaded the anticancer drug DM1 in the polymersome via dynamic disulfide bonding. The resulted trastuzumab-polymersome-DM1 (Tra-PS-DM1) exhibits a mean size of 95.3 nm and remarkable drug loading efficiency % of 99.3%. In addition to its superior stability, we observed the rapid release of DM1 in a controlled manner under reductive conditions. Compared to the native polymersomes, Tra-PS-DM1 has shown greatly improved cellular uptake and significantly reduced IC50 up to 17-fold among HER-2-positive cancer cells. Moreover, Tra-PS-DM1 demonstrated superb growth inhibition of HER-2-positive tumoroids; specifically, BT474 tumoroids shrunk up to 62% after 12 h treatment. With exceptional stability and targetability, the PG-shelled Tra-PS-DM1 appears as an attractive approach for HER-2-positive tumor treatment.
Weniger anzeigen1. Recent years have witnessed a surge in research on the effects of multiple stressors in freshwater ecosystems. While studies have increased, the synthesis of their findings into a broader understanding of ecosystem-level effects remains an ongoing endeavour. Leaf litter decomposition, a frequently investigated and pivotal ecosystem function in freshwaters, is sensitive to changes in abiotic conditions and biotic communities, and therefore susceptible to multiple-stressor effects. 2. Here, we synthesize findings from 27 manipulative experimental studies encompassing 61 responses of litter decomposition to paired stressors such as warming, nutrient enrichment and emerging pollutants in freshwater ecosystems. We calculated the individual and overall interaction effect sizes resulting from two stressors occurring simultaneously. Furthermore, we analysed the effect of moderator variables in the size and direction of interaction effect sizes using a meta-analytical approach. 3. Although the vote-counting method showed additive interactions to dominate individual observations (91.8%), weighted random-effects meta-analysis revealed an overall antagonistic interaction between stressors (i.e. the cumulative effect of paired stressors on litter decomposition was less than the sum of their single effects). Our results emphasized the influence of experimental characteristics such as macroinvertebrate involvement, habitat type (lentic vs. lotic) and litter quality (assumed from plant mycorrhizal association) in shaping the responses of litter decomposition to multiple stressors. 4. Our meta-analysis highlights the need to incorporate local ecological complexities in manipulative experiments to improve predictions of multiple-stressor effects on biodiversity and ecosystem functions. The present study underscores the importance of considering biotic interactions and adopting the metacommunity framework in conservation and restoration actions to support the management of freshwater ecosystems in an era of rapid global change.
Weniger anzeigenWe introduce a new class of random Gottesman-Kitaev-Preskill (GKP) codes derived from the cryptanalysis of the so-called NTRU cryptosystem. The derived codes are good in that they exhibit constant rate and average distance scaling Δ∝√n with high probability, where n is the number of bosonic modes, which is a distance scaling equivalent to that of a GKP code obtained by concatenating single mode GKP codes into a qubit-quantum error correcting code with linear distance. The derived class of NTRU-GKP codes has the additional property that decoding for a stochastic displacement noise model is equivalent to decrypting the NTRU cryptosystem, such that every random instance of the code naturally comes with an efficient decoder. This construction highlights how the GKP code bridges aspects of classical error correction, quantum error correction as well as post-quantum cryptography. We underscore this connection by discussing the computational hardness of decoding GKP codes and propose, as a new application, a simple public key quantum communication protocol with security inherited from the NTRU cryptosystem.
Weniger anzeigenThe serine protease trypsin forms a tightly bound inhibitor complex with the bovine pancreatic trypsin inhibitor (BPTI). The complex is stabilized by the P1 residue Lys15, which interacts with negatively charged amino acids at the bottom of the S1 pocket. Truncating the P1 residue of wildtype BPTI to α-aminobutyric acid (Abu) leaves a complex with moderate inhibitor strength, which is held in place by additional hydrogen bonds at the protein–protein interface. Fluorination of the Abu residue partially restores the inhibitor strength. The mechanism with which fluorination can restore the inhibitor strength is unknown, and accurate computational investigation requires knowledge of the binding and unbinding pathways. The preferred unbinding pathway is likely to be complex, as encounter states have been described before, and unrestrained umbrella sampling simulations of these complexes suggest additional energetic minima. Here, we use random acceleration molecular dynamics to find a new metastable state in the unbinding pathway of Abu-BPTI variants and wildtype BPTI from trypsin, which we call the prebound state. The prebound state and the fully bound state differ by a substantial shift in the position, a slight shift in the orientation of the BPTI variants, and changes in the interaction pattern. Particularly important is the breaking of three hydrogen bonds around Arg17. Fluorination of the P1 residue lowers the energy barrier of the transition between the fully bound state and prebound state and also lowers the energy minimum of the prebound state. While the effect of fluorination is in general difficult to quantify, here, it is in part caused by favorable stabilization of a hydrogen bond between Gln194 and Cys14. The interaction pattern of the prebound state offers insights into the inhibitory mechanism of BPTI and might add valuable information for the design of serine protease inhibitors.
Weniger anzeigenThe Babylonian horoscopes, edited by Rochberg in 1998, contain sets of astronomical and astrological data on dates of, or close to, individuals’ births. Each element of these short and concise texts reflects the astral divinatory practices and astronomical observation developed over the first millennium BC, as well as the latest innovations, including the zodiac as coordinate system and the occurrence of new astrological schemes partly based on it, which had previously remained obscure. In this paper, I present a new interpretation of the astrological terminology and the schemes that underly some of the data in the Babylonian horoscopes.
Weniger anzeigenStandardised terminology in science is important for clarity of interpretation and communication. In invasion science – a dynamic and rapidly evolving discipline – the proliferation of technical terminology has lacked a standardised framework for its development. The result is a convoluted and inconsistent usage of terminology, with various discrepancies in descriptions of damage and interventions. A standardised framework is therefore needed for a clear, universally applicable, and consistent terminology to promote more effective communication across researchers, stakeholders, and policymakers. Inconsistencies in terminology stem from the exponential increase in scientific publications on the patterns and processes of biological invasions authored by experts from various disciplines and countries since the 1990s, as well as publications by legislators and policymakers focusing on practical applications, regulations, and management of resources. Aligning and standardising terminology across stakeholders remains a challenge in invasion science. Here, we review and evaluate the multiple terms used in invasion science (e.g. ‘non-native’, ‘alien’, ‘invasive’ or ‘invader’, ‘exotic’, ‘non-indigenous’, ‘naturalised’, ‘pest’) to propose a more simplified and standardised terminology. The streamlined framework we propose and translate into 28 other languages is based on the terms (i) ‘non-native’, denoting species transported beyond their natural biogeographic range, (ii) ‘established non-native’, i.e. those non-native species that have established self-sustaining populations in their new location(s) in the wild, and (iii) ‘invasive non-native’ – populations of established non-native species that have recently spread or are spreading rapidly in their invaded range actively or passively with or without human mediation. We also highlight the importance of conceptualising ‘spread’ for classifying invasiveness and ‘impact’ for management. Finally, we propose a protocol for classifying populations based on (i) dispersal mechanism, (ii) species origin, (iii) population status, and (iv) impact. Collectively and without introducing new terminology, the framework that we present aims to facilitate effective communication and collaboration in invasion science and management of non-native species.
Weniger anzeigenAnthropogenic activity has irreparably altered the ecological fabric of Earth. The emergence of ecological novelty from diverse drivers of change is an increasingly challenging dimension of ecosystem restoration. At the same time, the restorationist's tool kit continues to grow, including a variety of powerful and increasingly prevalent technologies. Thus, ecosystem restoration finds itself at the center of intersecting challenges. How should we respond to increasingly common emergence of environmental system states with little or no historical precedent, whilst considering the appropriate deployment of potentially consequential and largely untested interventions that may give rise to organisms, system states, and/or processes that are likewise without historical precedent? We use the term bionovelty to encapsulate these intersecting themes and examine the implications of bionovelty for ecological restoration.
Weniger anzeigenWhole Institution Approaches (WIAs) to sustainability in education emphasize the strong link between the socio-physical environment and the learning processes and outcomes. However, there has been a lack of instruments for quantifying the implementation of WIAs based on the experience of learners and educators. In this article, we present the systematic development, pretesting, validation and first application of a novel WIA-Scale (learners: 13 items, educators: 15 items). As part of a large-scale assessment in Germany (school education, vocational education and higher education; n = 2,985), we apply the WIA-Scale and assess how WIAs are related to the effectiveness of sustainability learning. Based on extensive validation, the scale quality was evaluated as high. The application showed that young people who experience more sustainability in line with the WIA feel strongly more motivated and empowered by their educational institution to contribute to sustainability. Also, regression modeling revealed that WIA implementation is the strongest of various predictors of how sustainable learners act beyond the educational institution. Further, educators who experience more sustainability in line with the WIA feel considerably more motivated and report more sustainable behavior. They also view Education for Sustainable Development (ESD) as more relevant and participate more frequently in training on ESD. For future use, we provide the WIA-Scale in its original version, a 7/8-item variant and a one-item proxy. The scale may be used as a process indicator for high-quality sustainability education and as part of organizational development. Overall, the study shows that experienced WIAs are measurable and highly effective for quality sustainability learning.
Weniger anzeigenPurpose
To propose a paradigm change for the validation procedures of medication adherence questionnaires.
Methods
A total of 121 validation procedures of unique questionnaires for medication adherence were analyzed.
Results
“Construct validity” and “internal consistency” were most often assessed, and test results varied largely. A more in-depth analysis indicated that the assessment of medication non-adherence included distinct but related constructs, such as the extent to which doses are missed, and the attempt to identify different facets of medication-taking behavior. Consequently, each construct requires a different measurement approach with different psychometric tests for establishing its validity and reliability.
Conclusion
Results show that assessing the validity and reliability of adherence questionnaires with standard procedures including statistical tests is inconclusive. Refinement of the constructs of non-adherence is needed in pharmacy and medical practice. We suggest a distinction between the (i) extent of missed doses over the past 2 weeks, (ii) modifiable reasons for non-adherence behavior, and (iii) unmodifiable factors of non-adherence. Validation procedures and corresponding statistical methods should be selected according to the specific single constructs.
Weniger anzeigenWe established confrontations between two different fungi, i.e., the maize anthracnose and stalk rot pathogen Colletotrichum graminicola, and the ubiquitous fungus Aspergillus nidulans, and different biocontrol species, i.e., Bacillus subtilis, Bacillus velezensis, and Bacillus amyloliquefaciens. In all fungus–bacterium confrontations tested, growth arrest and, thus, distance inhibition was observed on solid substrata. LC–MS/MS analyses of culture filtrates suggested formation of several metabolites only synthesized in confrontations. Interestingly, microscopy of fungal hyphae grown in liquid medium showed protrusions and color changes occurred only in media harboring fungus-bacterium confrontations. These observations indicate metabolic re-programming and suggest formation of putative secondary metabolites in interactions involving microbial biocontrol agents.
Weniger anzeigenLaser-induced forward transfer (LIFT) of polymers is a versatile printing method for parallel in situ synthesis of peptides on microarrays. Chemical building blocks embedded in a polymer matrix are transferred and coupled in a desired pattern to a surface, generating peptides on microarrays by repetitive in situ solid-phase synthesis steps. To date, the approach is limited to simple, heat induced chemical reactions. The VaporLIFT method, disclosed here, combines LIFT with chemical vapor glycosylation to rapidly generate glycans on microarray surfaces while maintaining inert, low temperature conditions required for glycosylations. Process design and parameter optimization enables the synthesis of a collection of glycans at defined positions on a glass surface. The synthetic structures are detected by mass spectrometry, fluorescently labeled glycan-binding proteins, and covalent staining with fluorescent dyes. VaporLIFT is ideal for parallel screening of other chemical reactions, that require inert and well-defined reaction conditions.
Weniger anzeigenThe monazite-cheralite solid solutions LnPO4-Ca0.5Th0.5PO4 with Ln = La, Gd were prepared via a co-precipitation route, showcasing an optimised, scalable synthesis procedure for a possible waste form accommodating high level liquid waste streams. A distortion of the cheralite structure with respect to the monazite structure was observed throughout both solid solutions as evidenced by a deviation of the lattice parameters from the linear behaviour known from other monazite solid solutions. Using a high temperature flux method, cheralite single crystals were grown for the first time for in-depth structural investigations. Both thorium and calcium were found to deviate from the central position of the LnO9 polyhedron, supporting previous neutron diffraction investigations of identical cheralite samples.
Weniger anzeigenZirconia-based ceramics are promising host matrices for the immobilization of radionuclides in high-level waste streams due to their high radiation resistance and chemical stability. This study explores coprecipitation and different solid-state synthesis techniques to produce phase-pure zirconia-based ceramics with varying cerium and neodymium co-doping. Varying the dopant concentration enabled the synthesis of zirconates with monoclinic, cubic defect fluorite, and cubic pyrochlore structures. Powder X-ray diffraction was used for phase identification. In the case of coprecipitation, all synthesized compositions were predominantly phase-pure. Solid-state synthesis techniques included manual mixing of metal oxide powders with mortar and pestle, mechanical mixing in a ball mill, and magnetic mixing in a slurry. All solid-state mixing methods produced heterogeneous ceramics, featuring multiple phases, with manual mixing yielding the most phase-pure product. Extending the grinding time, re-sintering of the solid phases, and an increased Nd content were found to enhance the phase purity.
Weniger anzeigenThis article undertakes a crucial examination of Kant’s depiction of the interconnectedness between human reason and the divine. The argument posits that Kant conceptualizes reason as inherently founded on a divine basis. The primary objective of this article is not to delve into whether Kant endorses or dismisses specific Christian doctrines, or if his portrayal of reason aligns with a particular strand of Christian thought. Instead, the aim is to chart an interpretive middle path – one that embraces the profound philosophical underpinnings embedded in Kant’s rationalist legacy while recognizing the inherent limitations he imposes on human reason. The conclusion drawn is that Kant’s account of reason tends towards the divine, though the precise nature of this interconnectedness remains shrouded in mystery.
Weniger anzeigenThe self-identification of Sweden and Canada as exceptionally caring and ethical states committed to the goal of global gender justice has been reinforced through their adoption of feminist foreign policies (FFPs). However, despite the enthusiasm surrounding the potential of feminism as an ethical approach to foreign policy making, critics have drawn attention to the many failings of FFPs that hamper their ability to bring about transformative change. This article posits that the shortcomings of Swedish and Canadian FFPs are rooted in an unacknowledged legacy of colonial power relations. It is from within this history of violence that Swedish and Canadian practices of feminism both “at home” and “abroad” can be seen as a re-articulation of colonialism. Through two illustrative narrative readings of reconciliation efforts, the article examines state provisions of hierarchically imposed, paternalistic expressions of care that silence Indigenous “articulations of self-care.” As such, it addresses a significant gap in the literature on FFPs by highlighting the risk of self-proclaimed “caring” feminist states reproducing colonial power relations within and beyond borders.
Weniger anzeigenThis study investigates the determinants and dynamics of the linguistic features of key audit matters (KAMs) in European countries. Using natural language processing algorithms, including FINBERT, I quantify stylistic and content-based text characteristics at the KAM level and find that KAM length, readability, sentiment, quantitative density, specificity, the degree of forward-looking statements, and the extent of boilerplate language are associated with the type of KAM topics, client attributes, and audit firm characteristics. In additional analyses, I also find early empirical evidence of a time trend in these linguistic features. Since their introduction in 2016, KAMs are becoming longer, more quantitative, more specific, but also include more boilerplate phrases. Collectively, the results of the study contribute to a more nuanced understanding of the determinants and dynamics of KAM disclosures.
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