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It has been shown in \cite{Tong:2022gpg} that shallow water in the Euler description admits a dual gauge theory formulation. We show in the Lagrange description this gauge symmetry is a manifestation of the 2 dimensional area-preserving diffeomorphisms. We find surface charges associated with the gauge symmetry and their algebra, and study their physics in the shallow water system. In particular, we provide a local generalization of the Kelvin circulation theorem. In the linear shallow water case, the charges form a u(1) current algebra with level proportional to the Coriolis parameter over the height of the fluid. We also study memory effect for the gauge theory description of the linearized shallow water and show Euler, Stokes and Darwin drifts can be understood as a memory effect and/or change of the surface charges in the gauge theory description., Comment: 26 pages, 1 figure

The interaction of sedimentary systems with oceanographic processes in deep-water environments is not well understood yet, despite its importance for palaeoenvironmental reconstructions, and for a full understanding of source-to-sink sediment transport. The aim of this study is to improve the understanding of how contourite moats, elongated depressions formed by bottom currents associated with contourite drifts, develop and of the link between moat-drift system morphology and bottom current dynamics. This study provides a systematic comparison of 185 cross-sections of moat-drift systems distributed at 39 different locations worldwide, and a detailed analysis of the morphology of six moats that cover a wide range of typical geological and hydrodynamic settings. Additionally, in situ measured current data were analysed to better link hydrodynamics to moat morphology. The median of all profiles across all moat-drift systems reveals a 50 m relief, a width of 2.3 km, a relief to width ratio of 0.022, a slope angle of 6°, a drift angle of 3° and a concave-up shaped morphology. Moats can be over 100 km long. Some moats are driven by sediment erosion while others are depositional and primarily exist due to differential sedimentation inside the moat compared to the drift alongside the moat. A new sub-classification of moat-drift systems based on their stratigraphy is proposed. This classification distinguishes moats depending on the degree of erosion versus deposition. No relation is found between latitude and moat-drift morphology or stratigraphy in the analysed examples. The combined data indicate that a steeper slope focuses the current more than a gentle slope, resulting in an increase of the relief-width ratio and drift angle. Thus, this study provides new insides into the interaction of ocean currents with sedimentary morphology, which thereby affects the evolution of a poorly understood deepwater sedimentary system.

Environmental cues, such as physical forces and heterotypic cell interactions play a critical role in cell function, yet their collective contributions to transcriptional changes are unclear. Focusing on human endothelial cells, we performed broad individual sample analysis to identify transcriptional drifts associated with environmental changes that were independent of genetic background. Global gene expression profiling by RNA sequencing and protein expression by liquid chromatography-mass spectrometry directed proteomics distinguished endothelial cells in vivo from genetically matched culture (in vitro) samples. Over 43% of the transcriptome was significantly changed by the in vitro environment. Subjecting cultured cells to long-term shear stress significantly rescued the expression of approximately 17% of genes. Inclusion of heterotypic interactions by co-culture of endothelial cells with smooth muscle cells normalized approximately 9% of the original in vivo signature. We also identified novel flow dependent genes, as well as genes that necessitate heterotypic cell interactions to mimic the in vivo transcriptome. Our findings highlight specific genes and pathways that rely on contextual information for adequate expression from those that are agnostic of such environmental cues.

Alla avloppslösningar kräver skötsel och underhåll för att fungera ändamålsenligt under hela sin livslängd. Underhållsbehovet varierar beroende på storlek, typ och reningsgrad. I Havs- och vattenmyndighetens vägledning om prövning av små avlopp finns ett avsnitt om drift- och underhållsinstruktion samt ett översiktligt informationsblad. Redan i tillståndsansökan bör sökanden redovisa anläggningens behov av underhåll, kontroll och service i en så kallad drift- och underhållsinstruktion. Instruktionen bör innehålla både den egenkontroll som verksamhetsutövaren själv avser utföra och den eventuella kontroll som behöver utföras av sakkunnig. Instruktionen måste sammanfattningsvis innehålla nödvändiga uppgifter för att säkerställa anläggningens funktion i drift. Tidigare studier om uppföljande besök på prefabricerade markbädd visade att det finns brist på tydliga skötselinstruktioner till fastighetsägaren och brist på insikt om skötselansvar hos fastighetsägarna. Syftet med detta projekt var att undersöka i vilken utsträckning det finns drifts- och underhållsinstruktioner som motsvarar HaV:s nuvarande vägledning för markbaserade avloppsprodukter på marknaden, samt att i dialog med branschen utvärdera om det finns anledning att göra förändring i vägledning, i drift- och underhållsinstruktioner för markbaserade avloppsprodukter på marknaden och/eller i fysisk utformning av anläggningarna.

The encoding and exploitation of semantics has been gaining popularity, as exemplified by the uptake of digital ontologies and knowledge graphs. However, the semantics of domain objects usually do not reflect how they evolved over time, i.e., which events their dynamic transitions are based on. While a number of methods have been proposed to trace events and their impacts on a domain, there is a paucity of approaches to effectively join them. Thus, we combine event calculus as an analytical approach for modeling causal relationships between events and effects with semantic drifts as an empirical approach for quantifying the impact of domain updates. We demonstrate how their respective weaknesses can be addressed and how their interaction can improve the representation of semantic transitions.

Promoting the performance of catalytic systems by incorporating small amount of alkali has been proved effective for several reactions whilst controversial outcomes are reported for the synthetic natural gas production. This work studies a series of Ni catalysts for CO2 and CO methanation reactions. In-situ DRIFTS spectroscopy evidenced similar reaction intermediates for all evaluated systems and it is proposed a reaction mechanism based on: i) formate decomposition and ii) hydrogenation of lineal carbonyl species to methane. Compared to bare Ni, the enhanced CO2 methanation rates attained by NiFe/Al and NiFeK/Al systems are associated to promoted formates decomposition into lineal carbonyl species. Also for CO methanation, the differences in the catalysts’ performances were associated to the relative concentration of lineal carbonyl species. Under CO methanation conditions and opposing the CO2 methanation results where the incorporation of K delivered promoted catalytic behaviours, worsened CO methanation rates were discerned for the NiFeK/Al system.