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Negotiating contingency : between personalisation and customisation in digital hearing systems
No full textThis paper explores how digital hearing systems transform auditory experiences through system-sided personalisation and user-sided customisation. Drawing on Niklas Luhmann’s concept of contingency, it critiques a central paradox: while these devices aim to minimise unpredictability, their rigid settings create new uncertainties that users must actively address. Users navigate the tension between professionally standardised adaptations of digital hearing devices to meet their personal needs and the individual responsibility of customising their hearing through continuous self-monitoring and self-fitting. This challenges traditional notions of “natural” or “normal” and hearing with digital hearing systems, revealing a complex interplay between algorithmic control and user autonomy. By analysing research, ads and exemplary consumer insights in an online hearing forum the paper highlights how digital hearing systems embody a techno-mediated approach to hearing. Users are tasked with reconciling structured auditory norms with personal listening preferences, transforming hearing into a “self-technology” shaped by individual agency within a framework of contingency.publishe
Thermomonospora spp. are implicated in the biodegradation of long-chain aliphatic polyester bioplastics during thermophilic composting
No full textBiodegradable plastics are an important component for achieving a circular polymer economy. To be considered biodegradable at the regulatory level, plastics must pass standardized tests, for example under industrial composting conditions at 58 °C (ISO 14855-1). Although such tests are frequently applied, little is known about the microorganisms catalyzing these degradation processes. Recently, bioplastics with properties similar to polyethylene, Long-Chain Aliphatic Polyesters (LCAP), for example polyester 1,18-octadecanediol- alt -1,18-octadecanedioic acid (abbreviated PE-18,18), were shown to biodegrade under industrial composting conditions. In this work, we analyzed the microbial communities that had developed in the compost treatments at the end of the biodegradation test for three different LCAPs (PE-18,18, PE-12,12 and PE-2,18) relative to the untreated controls, via amplicon-sequencing of bacterial 16S and fungal ITS2 rDNA. This revealed significant treatment-induced shifts in the bacterial communities ( p < 0.05), with Pseudonocardia and Thermomonospora ASVs enriched in all LCAP-treated samples compared to the controls ( p ≤ 0.0001), while no pronounced shifts were observed for the fungal community. Thermomonospora sequences showed high similarity to T. curvata DSM43183, which encodes the known polyester hydrolase Tcur1278, and the presence of gene tcur1278 was confirmed in LCAP-treated samples via PCR. Enzyme assays with heterologously expressed and partially purified Tcur1278 demonstrated its activity on PE-2,18 LCAP, releasing up to 230 μmol of soluble monomers over 48 h at 50 °C. Hence, our study implicated Thermomonospora species in LCAP degradation during thermophilic composting, based on taxonomic enrichment, and provided evidence linking the detected phylotypes to Tcur1278, the first bacterial enzyme demonstrated to depolymerize LCAP. It thereby is the first evidence for an ecological relevance of Tcur1278-encoding Thermomonospora phylotypes for bioplastic degradation in situ .publishe
How to increase consumer demand for GHG-mitigating ingredients? : A case study of green restaurants in Taiwan
No full textThe hospitality industry’s commercial activities contribute to many negative environmental impacts; hence, promoting green restaurants is necessary. Considering the prevalent dining-out culture, green restaurants also bear the responsibility of changing people’s dietary habits to reduce greenhouse gas (GHG) emissions. This study examines how to increase people’s demand for green restaurants while changing their dietary habits to include more GHG-mitigating ingredients. Using the Attention, Interest, and Desire (AID) model and questionnaire survey, this study found that individuals exhibit a negative correlation between label attention and desire when interest is not considered. This may be attributed to the absence of sustainable social norms and values. In light of this, this study suggests that relevant government authorities could enhance subsidies for green restaurants, enabling them to compete with regular restaurants in terms of pricing, thereby accelerating the integration of green restaurants and GHG-mitigating ingredients into people’s daily lives.publishe
Patterns and Processes of Genomic Evolution Inferred From the Ten Smallest Vertebrate Genomes
No full textPufferfish exhibit the smallest vertebrate genomes, making them ideal models for investigating evolutionary patterns and processes that affect genome size. While the Takifugu rubripes genome was fully sequenced two decades ago, key evolutionary drivers remain elusive. We sequenced 10 pufferfish genomes and generated 35 transcriptomes and 13 methylomes to understand genomic evolutionary mechanisms. Comparative genomics revealed that transposable element suppression—rather than lineage‐specific conserved element loss—primarily underlies genome compaction. This is mediated by reductions in transposon‐associated enzymes that limit transposable element propagation and modify DNA repair mechanisms that promote genomic streamlining. Based on resolved phylogeny among nine Takifugu , it is found that introgression drives speciation of T. niphobles and T. oblongus , while long‐term linked selection dominates divergence in other species. Positive selection analyses highlighted mechanotransduction pathway genes (integrins, ion channel transport) that are functionally convergent with mammalian lung cell mechanisms, potentially supporting inflation‐based anti‐predatory strategies. Additionally, positive selection variants in genes that control lineage‐specific skin patterning and coloration, which are either selected for or are rewired in regulatory processes, might suggest a role for pigmentation during the rapid speciation of this lineage. This findings shed light on mechanisms enabling extreme vertebrate genome compaction and provide insights for genome engineering applications.publishe
Enlargement as high politics : New insights on the integration of the German Democratic Republic into the European Community
No full textAn essential part of the restructuring of the European security order after the Cold War is the Eastern enlargement of the European Community (EC). This article provides the hitherto missing explanation for the integration of the German Democratic Republic (GDR) into the EC. In alignment with neoclassical realism, I claim that high politics took precedence in this exceptional enlargement. Established theories underestimate the importance of security and power and, thereby, fall short in accounting for the fast-track accession of the GDR to the EC. I argue that the Federal Republic of Germany (FRG) pressed for a rapid reunification including the automatic accession of the GDR to the EC. Motivated by internal factors, the FRG’s government ventured a take-it-or-leave-it-offer that the other EC states acquiesced to under the threat of a German withdrawal from the EC with unforeseeable geopolitical consequences. The analysis builds on recently declassified, original documents collected from different archives.publishe
Produktionstechnologien für hochperformante kostengünstige IBC-Solarzellen - POPEI; Teilprojekt 3: "Materialuntersuchungen und Defektreaktionen von Ga-dotiertem kristallinem Si für IBC Solarzellen"
No full textpublishe
Amino acid metabolism of the thermophilic acetogen Thermacetogenium phaeum
No full textAnaerobic microbial degradation of the amino acids glycine and serine either occurs through enzymes of the so-called Stickland reaction or alternatively through the glycine cleavage system (GCS). In the mesophilic anaerobe Peptoclostridium acidaminophilum, initial glycine degradation proceeds through disproportionation to methylene tetrahydrofolate (THF) and acetyl-phosphate by GCS and glycine reductase. The thermophilic acetogen Thermacetogenium phaeum is able to utilize glycine, serine or threonine as sole carbon source, although it lacks genes for glycine reductase. In contrast, T. phaeum possesses genes for the GCS as well as for serine-converting enzymes, and the corresponding enzymes were specifically overabundant in the proteome and active. Among these enzymes, serine dehydratase was most active in serine-grown cells, even though its abundance in the proteome was comparably low. We suggest that two serine-converting enzyme systems (serine dehydratase, and the combination of glycine hydroxymethyltransferase and GCS) are used under different growth conditions: for breakdown of serine, T. phaeum most likely converts serine to pyruvate and ammonia by serine dehydratase, followed by acetate and ATP production via pyruvate dehydrogenase, phosphate acetyltransferase and acetate kinase. Electron carriers are then re-oxidized through CO2-fixation via the Wood-Ljungdahl pathway (WLP) of acetogenesis. When grown with glycine, the GCS most likely converts glycine to methylene-THF, which is then disproportionated to methenyl-THF and methyl-THF in the WLP. Glycine and serine both are excellent substrates for T. phaeum, yet in syntrophic cocultures with Methanothermobacter thermautotrophicus, acetate from glycine or serine degradation cannot be degraded further, as in syntrophic cultures with acetate as sole carbon source. This indicates an inhibitory or regulatory effect of glycine or serine degradation on acetate-degrading enzymes, resulting in the inability of T. phaeum to transition directly to syntrophic acetate oxidation after amino acid degradation.publishe
Homoterpene Biosynthesis in Fungi
No full textHomoterpenes carrying an additional methyl group in their carbon backbones are an emerging class of natural products that challenge the biogenic isoprene rule, stating that terpenes are composed of integer multiples of C5 units. We and others have recently shown that biosynthetic pathways to homoterpenes are widespread in bacteria, leading either to specialized scaffolds such as the “Greek philosophers homoterpenes” in Pseudomonadota or to simple methyl analogs of central eudesmanes and germacranes (“humanists homoterpenes”) in Actinomycetota. Here we report the discovery of the first homoterpene biosynthetic pathway in the fungal kingdom using targeted genomic data mining in combination with in vitro pathway reconstitution. Functional analyses of a fungal methyltransferase (NdiMT) and terpene cyclase (NdiTC) pair from the plant-pathogenic fungus Neonectria ditissima, the causative agent of apple canker, led to the discovery of a novel homosesquiterpene featuring an intriguing heptamethylbicyclo[3.3.1]nonane scaffold. Phylogenetic analyses indicate that the fungus acquired the key methyltransferase via horizontal gene transfer from bacteria, whereas the terpene cyclase appears to have evolved from a fungal ancestor. The discovery raises fundamental questions about the evolutionary rationale and functional consequences of terpene methylation in nature.publishe
Topological classification of driven-dissipative nonlinear systems
No full textIn topology, averaging over local geometrical details reveals robust global features. These are crucial in physics for understanding quantized bulk transport and exotic boundary effects of linear wave propagation in (meta-)materials. Beyond linear Hamiltonian systems, topological physics strives to characterize open (non-Hermitian) and interacting systems. Here, we establish a framework for the topological classification of driven-dissipative nonlinear systems by defining a graph index for their Floquet semiclassical equations of motion. Our index builds upon the topology of vector flows and encodes the particle-hole nature of excitations around all out-of-equilibrium stationary states. Thus, we uncover the topology of nonlinear resonator’s dynamics under external and parametric forcing. Our framework sheds light on the topology of driven-dissipative phases, including under- to overdamped responses and symmetry-broken phases linked to population inversion. We therefore expose the pervasive link between topology and nonlinear dynamics, with broad implications for interacting topological insulators, topological solitons, neuromorphic networks, and bosonic codes.publishe
UniCor and UniCorP : A Novel Metric and Hierarchical Feature Selection Algorithm for Microbial Community Analysis
No full textThe rapid advancement of technologies and methods in the life sciences has significantly increased the availability of big data, presenting new challenges for its analysis. Microbiome datasets, in particular, are characterized by extensive feature sets with defined but complex hierarchical structures that are often overlooked or underutilized. Here we introduce a novel metric, UniCor, to identify UNIquely CORrelated eNtities (UNICORNs) in quantitative datasets associated with continuous target variables. These datasets may include microbiome community structures in relation to environmental factors (e.g., temperature, pH, salinity) or biotic variables (e.g., thermal tolerance, oxidative stress). The UniCor metric combines the uniqueness of a given feature within a dataset with its correlation to a target variable of interest. To further enhance its utility, we developed a propagation algorithm (UniCorP), which exploits inherent dataset hierarchies, such as taxonomic levels in microbiome datasets, by selecting and propagating features based on their UniCor metric. Using bacterial community datasets with hierarchical taxonomic annotations and various continuous environmental variables, we demonstrate the ability of the novel metric to reduce features and increase predictive performance in cross-validated Random Forest Regressions (RFR). After propagating features with UniCorP and enriching the hierarchical levels with UNICORNs, the predictive performance consistently outperformed control trials for taxonomic aggregation, even at the least granular hierarchical level, allowing a substantial reduction of the feature space. We also compared the metric to existing methods for feature aggregation, showing that it offers stable, competitive predictive performance and feature reduction, within a simple and adaptable framework.publishe