Colloidal stabilisation of all malt and adjunct lager beers through selective removal of haze sensitive glycoproteins using silica gel and tannoid polyphenols using polyvinylpolypyrrolidone (PVPP) or a polyvinylpyrrolidone (PVP)-modified silica gel has been demonstrated during full brewery production. At this scale PVPP and the PVP-modified silica gel exhibited equivalent binding capability for tannoid polyphenols although PVPP removed additional polyphenolic species. Characterisation of proanthocyanidins following treatment at 4°C with PVPP and the PVP-modified silica gel silica co-product confirmed that PVPP removes a wider range of polyphenolics. Both products exhibited poorer polyphenolic binding capability at 4°C as would be expected for a physical adsorption process.

A fundamental problem in developmental biology is understanding how complex patterns and organised tissues develop from a small group of nearly identical cells. A wealth of experimental data has exposed the complexity of the molecular networks guiding cellular decisions of organisation and patterning – networks whose output evolves over space and time as development progresses. Integrating this data into reaction–diffusion (RD) mathematical models that describe the spatiotemporal dynamics of molecular species during development provides a rigorous approach to test the plausibility of hypothesised mechanisms guiding pattern formation, to understand how the complexity is regulated and to optimise experimental design. RD modelling provides a complementary mode of inquiry that both depends on and informs experimental research. RD systems are used in developmental biology to model morphogen‐mediated pattern formation. Key Concepts Integrating wet lab experiments with spatiotemporal mathematical modelling enables greater hypothesis testing ability than either method alone. Viewing developing embryos as engineered dynamical systems designed to satisfy performance objectives is a helpful mental framework for model‐based analysis in developmental biology. Reaction‐transport equations (simplified to reaction–diffusion here) are indispensable when studying developmental patterning and morphogenesis. Turing networks and positional information are the primary conceptual bases of pattern specification. Model reproducibility is as important to consider as experimental reproducibility and should be the focus during implementation and communication of the model definition.

Positional information encoded in signaling molecules is essential for early patterning in the prosensory domain of the developing cochlea. The cochlea contains an exquisite repeating pattern of sensory hair cells and supporting cells. This requires precision in the morphogen signals that set the initial radial compartment boundaries, but this has not been investigated. To measure gradient formation and morphogenetic precision in developing cochlea, we developed a quantitative image analysis procedure measuring SOX2 and pSMAD1/5/9 profiles in mouse embryos at embryonic day (E)12.5, E13.5, and E14.5. Intriguingly, we found that the pSMAD1/5/9 profile forms a linear gradient in the medial ~75% of the PSD during E12.5 and E13.5. This is a surprising activity readout for a diffusive BMP4 ligand secreted from a tightly constrained lateral region since morphogens typically form exponential or power-law gradient shapes. This is meaningful for gradient interpretation because while linear profiles offer the theoretically highest information content and distributed precision for patterning, a linear morphogen gradient has not yet been observed. In addition to the information-optimized linear profile, we found that while pSMAD1/5/9 is stable during this timeframe, an accompanying gradient of SOX2 shifts dynamically. Third, we see through joint decoding maps of pSMAD1/5/9 and SOX2 that there is a high-didelity mapping between signaling activity and position in the regions soon to become Kolliker's organ and the organ of Corti, where radial patterns are more intricate than lateral regions. Mapping is ambiguous in the prosensory domain precursory to the outer sulcus, where cell fates are uniform. Altogether, this research provides new insights into the precision of early morphogenetic patterning cues in the radial cochlea prosensory domain.

Positional information encoded in signaling molecules is essential for early patterning in the prosensory domain of the developing cochlea. The sensory epithelium, the organ of Corti, contains an exquisite repeating pattern of hair cells and supporting cells. This requires precision in the morphogen signals that set the initial radial compartment boundaries, but this has not been investigated. To measure gradient formation and morphogenetic precision in developing cochlea, we developed a quantitative image analysis procedure measuring SOX2 and pSMAD1/5/9 profiles in mouse embryos at embryonic day (E)12.5, E13.5, and E14.5. Intriguingly, we found that the pSMAD1/5/9 profile forms a linear gradient up to the medial ~ 75% of the PSD from the pSMAD1/5/9 peak in the lateral edge during E12.5 and E13.5. This is a surprising activity readout for a diffusive BMP4 ligand secreted from a tightly constrained lateral region since morphogens typically form exponential or power-law gradient shapes. This is meaningful for gradient interpretation because while linear profiles offer the theoretically highest information content and distributed precision for patterning, a linear morphogen gradient has not yet been observed. Furthermore, this is unique to the cochlear epithelium as the pSMAD1/5/9 gradient is exponential in the surrounding mesenchyme. In addition to the information-optimized linear profile, we found that while pSMAD1/5/9 is stable during this timeframe, an accompanying gradient of SOX2 shifts dynamically. Last, through joint decoding maps of pSMAD1/5/9 and SOX2, we see that there is a high-fidelity mapping between signaling activity and position in the regions that will become Kölliker’s organ and the organ of Corti. Mapping is ambiguous in the prosensory domain precursory to the outer sulcus. Altogether, this research provides new insights into the precision of early morphogenetic patterning cues in the radial cochlea prosensory domain.

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