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Mitochondrial Genomes of Three Melampus Species (Ellobiidae; Gastropoda)
No full textMelampus bidentatus was recently divided into three genetically divergent cryptic species: Melampus bidentatus, Melampus jaumei, and Melampus gundlachi. We have assembled and annotated a mitochondrial genome for each of these species. Comparisons with other taxa showed that these three species possess a gene order that is distinct from the conserved gene order found in the six (out of nine available) Ellobiid genera. Among the species with a derived gene order, mean nucleotide divergence over all genes was on average 1.57× higher than among mitogenomes with the conserved gene order. This suggests varying evolutionary rates of mitochondrial genes in this family.</p
Red-to-Near-Infrared Electroluminescence and Low-Threshold Amplified Spontaneous Emission from Solution-Processable Fluorescent Diketopyrrolopyrrole Derivatives
No full textA detailed investigation of the photophysical, electroluminescence, and amplified spontaneous emission (ASE) properties of two solution-processable fluorescent diketopyrrolopyrrole derivatives is reported. Photophysical measurements are carried out in solution and blend films containing a 4,4′-bis(N-carbazolyl)-1,10-biphenyl (CBP) or a poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,8-diyl)] host, to gain important insights into the excited state behavior of these dyes. Quantum chemical calculations are also carried out to support the experimental findings. An optimization of the doping concentration in the CBP blends is necessary to reduce the strong aggregation. This optimization led for both near-infrared-emitting dyes to a substantial increase of the photoluminescence quantum yield, which can reach values as high as 60%. It is also found that the blend films show excellent ASE properties with a threshold as low as 3.5–4.5 μJ cm−2 for peak wavelengths of 739 and 727 nm. In addition, the electroluminescence properties of the two organic laser dyes are examined in organic light-emitting diodes (OLEDs). The best OLED device shows a maximum external quantum efficiency value of around 2%. Overall, this study demonstrates the excellent potential of diketopyrrolopyrrole derivatives for high-performance near-infrared organic semiconductor lasers and provides useful information for the design of new efficient near-infrared emitters for optoelectronic applications.</p
Model informed drug development and CAR-T cells:A review of their use and credibility assessment in the context of EMA centralized procedures
No full textNeuro-symbolic procedural semantics for explainable visual dialogue
No full textThis paper introduces a novel approach to visual dialogue that is based on neuro-symbolic procedural semantics. The approach builds further on earlier work on procedural semantics for visual question answering and expands it with neuro-symbolic mechanisms that handle the challenges that are inherent to dialogue, in particular the incremental nature of the information that is conveyed. Concretely, we introduce (i) the use of a conversation memory as a data structure that explicitly and incrementally represents the information that is expressed during the subsequent turns of a dialogue, and (ii) the design of a neuro-symbolic procedural semantic representation that is grounded in both visual input and the conversation memory. We validate the methodology using the MNIST Dialog and CLEVR-Dialog benchmark challenges and achieve a question-level accuracy of 99.8% and 99.2% respectively. The methodology presented in this paper contributes to the growing body of research in artificial intelligence that tackles tasks that involve both low-level perception and high-level reasoning using a combination of neural and symbolic techniques. It thereby leads the way towards the development of conversational agents that will be able to hold more explainable, natural and coherent conversations with their human interlocutors
Evidence That Dmrta2 Acts through Repression of Pax6 in Cortical Patterning and Identification of a Mutation Impairing DNA Recognition Associated with Microcephaly in Human
No full textDmrta2 (also designated Dmrt5) is a transcriptional regulator expressed in cortical progenitors in a caudomedialhigh/rostrolaterallow gradient with important roles at different steps of cortical development. Dmrta2 has been suggested to act in cortex development mainly by differential suppression of Pax6 and other homeobox transcription factors such as the ventral telencephalic regulator Gsx2, which remains to be fully demonstrated. Here we have addressed the epistatic relation between Pax6 and Dmrta2 by comparing phenotypes in mutant embryos or embryos overexpressing both genes in various allelic combinations. We show that Dmrta2 cooperates with Pax6 in the maintenance of cortical identity in dorsal telencephalic progenitors and that it acts as a transcriptional repressor of Pax6 to control cortical patterning. Mechanistically, we show that in P19 cells, Dmrta2 acts as a DNA binding-dependent repressor on the Pax6 E60 enhancer and that a point mutation that affects its DNA binding properties identified in a consanguineous family leads to agenesis of the corpus callosum, pachygyria, and the absence of the cingulate gyrus. Finally, we provide evidence that Dmrta2 binds components of the NuRD repressor complex and interacts with zinc finger proteins such as Zfp423. Together, our results highlight the importance and conserved function of Dmrta2 in cortical development and provide novel insights into its mechanism of action.</p
Time-resolved proteomic profiling of Cupriavidus metallidurans CH34 in the copper-induced viable-but-nonculturable state
No full textCopper-based materials are actively explored for their potential as antimicrobial agents. However, recent studies show that sublethal concentrations of Cu ions can induce the viable-but-nonculturable (VBNC) cell state in certain bacteria, hampering contamination control, and monitoring. In this study we contribute to the unravelling of this largely enigmatic phenomenon by determining the time-resolved proteome of Cu-treated Cupriavidus metallidurans CH34 during VBNC induction and resuscitation. High-throughput quantitative liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis was performed at multiple sample time points, revealing the cellular adaptations that trigger VBNC formation and the characteristic spontaneous recovery of culturability. Entry into the VBNC state correlated with a widespread response to oxidative stress as well as downregulated pyruvate metabolism. The expression of specific metal resistance determinants changed with Cu exposure time and culminated in the strong upregulation of proteins linked to periplasmic Cu ion detoxification during the resuscitation phase. We suggest that this delayed induction of Cu resistance proteins is paralleled by the gradual reconstitution of energy reserves through metabolization of intracellular polyhydroxybutyrate, as supported by flow cytometric fluorescence measurements. Furthermore, Cu-treated cells showed upregulation of several motility and chemotaxis proteins, and increased cell motility was observed phenotypically. Our results reveal a highly dynamic proteomic response, provide fundamental insights into the VBNC state and emphasize the advantages of time-resolved proteomic analysis.</p
Tracing online flood conversations across borders:A watershed level analysis of geo-social media topics during the 2021 European flood
No full textIn the face of rapid population growth, urbanisation, and accelerating climate change, rapid and accurate disaster detection has become critical to minimise human and material losses. In this context, geo-social media (referring to georeferenced social media posts) data have proven to be a sensible data source for tracing disaster-related conversations, especially during flood events. However, current research often neglects the relationship between information from social media posts and their corresponding geographical context. In this paper, we examine the emergence of disaster-related social media topics in relation to hydrological and socio-environmental features at the watershed level during the 2021 western European flood, while focusing on transboundary river basins. Building on an advanced machine-learning-based topic modelling approach, we show the emergence of flood-related geo-social media topics in both river-basin-specific and cross-basin contexts. Our analysis reveals distinct spatio-temporal dynamics in the public discourse, showing that timely topics describing heavy rainfall or flood damage were closely tied to immediate environmental conditions in upstream areas, while post-disaster topics about helping victims or volunteering were more prevalent in less affected areas located in both upstream and downstream areas. These findings highlight how social media responses to disasters differ spatially across watersheds and underscore the importance of integrating geo-social media analysis into disaster coordination efforts, opening new opportunities for transboundary collaborations and the coordination of emergency response along border-crossing rivers
A Two-Dimensional Swarmalator Model with Higher-Order Interactions
No full textWe study a simple two-dimensional swarmalator model that incorporates higher-order phase interactions, uncovering a diverse range of collective states. The latter include spatially coherent and gas-like configurations, neither of which appear in models with only pairwise interactions. Additionally, we discover bistability between various states, a phenomenon that arises directly from the inclusion of higher-order interactions. By analyzing several of these emergent states analytically, both for identical and nonidentical populations of swarmalators, we gain deeper insights into their underlying mechanisms and stability conditions. Our findings broaden the understanding of swarmalator dynamics and open new avenues for exploring complex collective behaviors in systems governed by higher-order interactions
Système hospitalier, transition écologique et bioéthique:repenser la question de l'autonomie
No full textLes hôpitaux modernes représentent une source majeure de pollution, liée à leur forte consommation énergétique, à la production massive de déchets et à la croissance des flux numériques. Or, leur fonctionnement repose sur un modèle libéral centré sur l’autonomie individuelle et la satisfaction du patient, ce qui freine la transition écologique du secteur. Un changement radical de valeurs s’impose. La bioéthique, traditionnellement mobilisée pour guider les pratiques hospitalières, est elle-même ancrée dans ces mêmes valeurs individualistes. Pourtant, un retour à ses racines – notamment chez Potter et Jahr – révèle une conception intégrative, relationnelle et écologique de l’éthique, orientée vers l’interdépendance humaine et le respect du vivant. Réactiver cette bioéthique oubliée pourrait fournir les bases d’un véritable tournant éco-responsable des institutions de santé