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Molecular basis of specificity in alternative splicing regulation through splicing regulator SRSF6
No full textAn overview of the rock art of AlUla: tracing changes in content and form across 12,000 years of human history
No full textBetween 2018 and 2021, the Identification and Documentation of Immovable Heritage Assets (IDIHA) Project recorded over 19,000 rock art panels in the AlUla (al-?Ul?) region of north-western Saudi Arabia. This study presents a chronological assessment of the corpus, drawing on superimpositions, datable motifs, inscriptions, and varnish formation, alongside a diachronic analysis of recurring themes. The rock art of AlUla spans more than 12,000 years, from the early Holocene to the recent past, with notable peaks in production during the Neolithic and, more substantially, the Iron Age and ?pre-Islamic? periods. These temporal fluctuations contrast with patterns observed at other northern Arabian sites and likely reflect population increase in the AlUla valley during the first millennium BCE and CE. Scenes of Neolithic cattle herding, Iron Age camel caravans, and Islamic-era battles offer insight into the lived experiences and symbolic expressions of AlUla's inhabitants across millennia.1 Introduction 2 Methods, Data and Technical Observations 2.1 Survey Methods and Data 2.2 Chronology 2.3 Rock Art Medium and Technique 3 Results 3.1 Distribution 3.2 Early Holocene Rock Art of the AlUla Region 3.3 Pre‐Neolithic/Neolithic Rock Art of the AlUla Region 3.3.1 Hunting Scenes 3.3.2 Neolithic Cattle and Other Livestock 3.3.3 Neolithic Human Figures 3.4 Bronze Age Rock Art of the AlUla Region 3.5 The Iron Age/‘Pre‐Islamic’ Rock Art of the AlUla Region 3.5.1 Camel Depictions 3.5.2 Livestock: Cattle, Sheep and Goat 3.5.3 Ibex 3.5.4 Riders and Battle Scenes 3.5.5 Human Figures 3.5.6 Hunting Scenes and Conflict With Carnivores 3.5.7 Herding Scenes 3.5.8 Caravans and Chariots 3.6 Recent Rock Art in the AlUla Region 3.6.1 Objects 4 Discussion 5 Conclusio
Isolating the global in the prehistory of the Ryūkyū islands
No full textHudson argues that the prehistoric Ryūkyū Islands were marked by a dynamic form of ‘global’ history despite their late adoption of farming, metallurgy, and state structures. Tracing early seafaring from Taiwan and Kyushu, the shell-bracelet trade with Kyushu elites, and contacts with Korea and Han China, the chapter situates the Ryūkyūs within wider Bronze Age processes of globalisation and ‘bronzisation’. At the same time, Hudson highlights patterns of cultural refusal and episodes of extreme isolation, particularly in the southern islands, positioning the Ryūkyūs within global networks while underscoring their distinctive, often resistant, historical trajector
Combining evolution and machine learning-guided pathway optimization to engineer a novel methylsuccinate module for synthetic C1 metabolism in vivo
No full textDe novo metabolic pathways open possibilities for sustainable biotransformations in microbes. However, the in vivo-implementation of such new-to-nature pathways is highly challenging and heavily relies on adaptive laboratory evolution (ALE) of the host's native metabolic network. Here, we assess how much this need for host-centric ALE can be overcome and/or complemented through the informed design of the newly introduced pathway. Exemplifying for a synthetic CO2-fixation module via methylsuccinate, we established methylsuccinate-dependent growth of Escherichia coli over six months by ALE of E. coli's native metabolism. In parallel, we developed a machine-learning guided workflow (MEVIS) for the automated engineering of the synthetic pathway, resulting in methylsuccinate-dependent growth within three weeks. Critically, performing MEVIS in the background of the ALE-evolved strain is necessary to further approach wild-type like growth, demonstrating how ALE in combination with machine-learning-guided lab automation holds great potential to accelerate and improve design-build-test-learn cycles in contemporary metabolic engineering.Competing Interest StatementThe authors have declared no competing interest.Max Planck Society, https://ror.org/01hhn8329Bosch Research Foundatio
Hydrological impact of near-surface soil warming in China’s Three Rivers Source Region during the seasonally heterogeneous precipitation period from 1998-2017
No full textThe Tibetan Plateau (TP) has experienced pronounced wetting since 1998. The Three Rivers Source Region (TRSR), an interior region of the TP, is underlain by both permafrost and seasonally frozen ground (SFG) that exhibit divergent thermal responses to climate change. However, the differential hydrological consequences of permafrost versus SFG degradation remain uncertain. Using observed soil temperatures from 21 meteorological stations for the period 1998–2017, we compare thermal dynamics throughout the soil profile between permafrost- and SFG-dominated watersheds of the TRSR and quantify their respective impacts on basin-scale hydrology during this marked wetting period. The results indicate that the observed precipitation pattern, which characterized by increased rainfall during warm season but decreased snow depth during cold season, accelerates near-surface soil warming in SFG catchments while amplifying subsurface thermal sensitivity in permafrost-dominated basins. As a whole, thermal degradation in permafrost-dominated catchments exerts a more immediate influence on streamflow than in SFG basins. Hydrological responses in permafrost catchments are contingent upon thermal stability: basins with low thermal stability (rapid Ground freezing index (GFI) decline) exhibit strong runoff sensitivity to permafrost dynamics, whereas basins with high thermal stability (moderate GFI decline) display significant streamflow effects only over longer timescales. Projected increased in precipitation will substantially modify the spatial heterogeneity of permafrost thermal stability, thereby exerting profound impacts on terrestrial water cycles within the “Asian Water Tower”
Accelerating the Development of Organic Solar Cells: A Standardized Protocol with Machine Learning Integration
No full textOrganic Photovoltaic (OPV) devices show a large gap between laboratory-recorded cells with over 20% efficiency and commercial roll-to-roll printed modules reaching a maximum half that efficiency. A novel OPV material not only needs high efficiency, but must be processable in architectures suited for large-scale applications and provide sufficient stability under various stress factors. We present a holistic screening protocol to cover all relevant aspects of OPV material development. Using machine learning techniques together with systematic experimental protocols, only a minimum amount of a novel semiconductor is necessary. We utilize process parameters, optical features, and IV data to explore the processing window, benchmark process stability, and enable structure-property predictions. We implement a combinatorial degradation protocol that investigates key stress factors, like temperature, oxygen, and illumination, at different stages of device fabrication. Testing partially finished devices, conventional and inverted architectures, as well as hole-only and electron-only devices, enables the identification of individual layers responsible for degradation. The protocol includes a solvent test to investigate processability with green solvents. The systematic data collected in this protocol provides a general and reliable basis for material development and the imminent creation of digital twins for OPV
Biomethanation of alkaline waste sludge in haloalkaline conditions: combined proof of concept experiments and technical economic evaluation
No full textA highly pure biomethane stream (≈97% CH4) was produced continuously under halo-alkaline conditions (pH > 9, 0.6 M Na+) from complex alkaline organic waste residue originating from biopolymer extraction from sewage sludge. During the proof-of-concept operation, the substrate was degraded with similar efficiency (40% of the volatile solids, VS) compared to neutral conditions (36% of the VS). Operational data was utilised in a technical evaluation to identify bottlenecks for full-scale implementation at an early stage of process development and for comparison to conventional biogas upgrading using pressure swing and membranes. Initially identified bottlenecks for alkaline fermentation were related to overcautious assumptions, while others could be technically solved. Alkaline fermentation offers an attractive method for supplying increasingly needed high-purity biomethane using various recalcitrant substrates that have undergone alkaline pre-treatment. This is more feasible than the conventional ex-situ biogas upgrading. Next, upscaling steps for alkaline fermentation should be pursued. Strategies for integrated CO2 sequestration and nutrient recovery are outlined, which will offer additional benefits in the future
Cell position is more important than cell shape or age for the acquisition of cell identity in the brown alga Ectocarpus
No full textThe brown alga Ectocarpus is a complex yet morphologically simple organism in which cells of the growing filament undergo changes in shape and relative position over time. Here we have investigated the role of cell age, cell position and cell shape in the establishment of cell identity in Ectocarpus. To understand how these factors act and combine to determine cell identity, we used laser capture microdissection (LCM) to isolate specific cell types from young sporophytes of Ectocarpus and then performed differential RNA-Seq analysis. Transcriptome data were used to allocate molecular signatures to cell identities and then cell populations were distinguished on the basis of age, shape, and position. Transcriptome profiling of a wild-type strain provided molecular signatures of five distinct cell identities. To dis-associate cell shape, age and position, we then analysed transcriptomes of two mutants in which the relationships between the three parameters were altered. Collectively our data revealed that molecular cell signatures are dependent primarily on cell position along the filament, and secondarily on cell shape
