Polysorbate identity and quantity dictate the extensional flow properties of protein-excipient solutions

While protein medications are promising for treatment of cancer and autoimmune diseases, challenges persist in terms of development and injection stability of high-concentration formulations. Here, the extensional flow properties of protein-excipient solutions are examined via dripping-onto-substrate extensional rheology, using a model ovalbumin (OVA) protein and biocompatible excipients polysorbate 20 (PS20) and 80 (PS80). Despite similar PS structures, differences in extensional flow are observed based on PS identity in two regimes: at moderate total concentrations where surface tension differences drive changes in extensional flow behavior, and at small PS:OVA ratios, which impact the onset of weakly elastic flow behavior. Undesirable elasticity is observed in ultra-concentrated formulations, independent of PS identity; higher PS contents are required to observe these effects than in analogous polymeric excipient solutions. These studies reveal novel extensional flow behaviors in protein-excipient solutions, and provide a straightforward methodology for assessing the extensional flow stability of new protein-excipient formulations.     

DFT simulation of HCl leaching over cellulase-mimetic solid acid catalyst for possible application in biohydrogen production

Cellulase-mimetic solid acid catalysts (CMSAC), having both cellulose-binding and catalytic sites, are known to have much lower activation energy and higher catalytic activity than traditional solid acid catalysts. It is an emerging greener and cost-friendly solution for producing biofuel, such as bio-hydrogen, from lignocellulose. However, in 2018 the widely used CMSAC, sulfonated chloromethyl polystyrene, was found to have its catalytic activity attributed to the in-situ release of HCl during catalytic hydrolysis, which is unexpected. An ab initio quantum calculation based on density functional theory (DFT) is performed to study its reaction mechanism. Results have shown that the most probable mechanism responsible for the in-situ release of HCl is through SN1 nucleophilic substitution. The simulation also predicted a surface reaction activation energy of 1.56 eV (35.97 kcal/mol), along the predicted minimum energy path (MEP). This is the first ab initio study to theoretically predict the HCl leaching mechanism from CMSAC before its industrial application.     

‘Problem families’ in public housing: discourse,commentary and (dis)order

This article contributes to a chain of literature extending back to the late nineteenth century on the ‘problem family’, particularly when encountered by housing providers as the ‘problem’ tenant. Using archival evidence of the techniques employed by one social housing provider in the mid-1970s to identify a definitive solution to the challenges posed by ‘problem’ households, I trace the patterns and practices in ‘problem family’ discourse more broadly, and their intersection with those of other discursive fields, particularly eugenics and social work. I show how attempts to define, identify and design models of rehabilitation for ‘problem families’ can be understood as forms of a discursive strategy which Foucault identified as ‘commentary’, and argue that such commentary remains intrinsic to welfare state efforts to tackle entrenched disadvantage.     

Recent Developments and Practical Feasibility of Polymer‐Based Antifouling Coatings

While nature has optimized its antifouling strategies over millions of years, synthetic antifouling coatings have not yet reached technological maturity. For an antifouling coating to become technically feasible, it should fulfill many requirements: high effectiveness, long‐term stability, durability, ecofriendliness, large‐scale applicability, and more. It is therefore not surprising that the search for the perfect antifouling coating has been going on for decades. With the discovery of metal‐based antifouling paints in the 1970s, fouling was thought to be a problem of the past, yet its untargeted toxicity led to serious ecological concern, and its use became prohibited. As a response, research shifted focus toward a biocompatible alternative: polymer‐based antifouling coatings. This has resulted in numerous advanced and innovative antifouling strategies, including fouling‐resistant, fouling‐release, and fouling‐degrading coatings. Here, these novel and exciting discoveries are highlighted while simultaneously assessing their antifouling performance and practical feasibility.     

Modelling vicious networks with P-graph causality maps

Clean Technologies and Environmental Policy - P-graph causality maps were recently proposed as a methodology for systematic analysis of intertwined causal chains forming network-like structures....     

A fuzzy optimization model for planning integrated terrestrial carbon management networks

Clean Technologies and Environmental Policy - Biochar application and enhanced weathering are negative emission technologies (NETs) with the potential for large-scale deployment for the removal of...     

Ozonation reduces sludge production and improves denitrification

The effectiveness of partial ozonation of return activated sludge for enhancing denitrification and waste sludge minimization were examined. A pair of nitrifying sequencing batch reactors was operated in either aerobic or alternating anoxic/aerobic conditions, with one control and one ozonated reactor in each set. The amount of solids produced decreased with the ozone dose. Biomass in the anoxic/aerobic reactor was easier to destroy (up to 25% of the initial excess sludge) than in the aerobic (10%) one, generating approximately twice as much soluble COD by cell lysis. Denitrification rate improved up to 60% due to additional carbon released by ozonation. Nitrification rates deteriorated much more in the aerobic than in the alternating reactor, possibly as a result of direct destruction of nitrifying autotrophs as well as competition created by growth of heterotrophs receiving the additional COD. Overall, ozonation provided the expected benefits in denitrification and had less impact on nitrification in the alternating reactors.     

Thoor Ballylee: icon of an Irish imaginary

W.B. Yeats' restoration and recreation of Ballylee Castle in the west of Ireland from 1916 as ‘Thoor Ballylee’ saw it become the symbol and metaphor of his work as a poet. With the help of the architect, William Scott, an exponent of the English Arts and Crafts school, Yeats placed the tower and its landscape at the centre of his vision of the Irish past. The Arts and Crafts aesthetic that underpinned Yeats' idealisation of Irish society opposed and decried the modernisation of rural Ireland, attempting to preserve it as an idyll for the urban intelligentsia. In his appropriation and reconstruction of Ballylee Castle Yeats sought both to locate himself amongst the peasantry of the west of Ireland whom he idealised in his work and to reassert his own roots amongst the dying colonial order. This paper explores the ambivalence of Yeats' cultural nationalism against the backdrop of republican violence and the emergence of the Free State.     

Atmospheric deposition of carbon and nutrients across an arid metropolitan area

Urbanization is increasing rapidly in semi-arid environments and is predicted to alter atmospheric deposition of nutrients and pollutants to cities as well as to ecosystems downwind. We examined patterns of wet and coarse dry deposition chemistry over a five-year period at 7 sites across the Central Arizona-Phoenix (CAP) study area, one of two urban sites within the National Science Foundation's Long-Term Ecological Research (LTER) program. Wet and dry deposition of organic carbon (oC) were significantly elevated in the urban core; in contrast, mean annual wet and dry fluxes of nitrogen (N) were low (<6 kg ha(-1) yr(-1)) compared to previous estimates and did not differ significantly among sites. Wet deposition of sulfate (SO(4)2-) was high across CAP (mean 1.39 kg ha(-1) yr(-1) as S) and represented the dominant anion in rainfall. Dry deposition rates did not show strong seasonal trends with the exception of oC, which was 3-fold higher in winter than in summer; ammonium (NH4+) deposition was high but more variable. Dry deposition of NO3- and oC was strongly correlated with particulate base cations and dust-derived soluble reactive phosphorus (SRP), suggesting that urban-derived dust is scrubbing the atmosphere of acidic gases and entrained particles and increasing local deposition. Differences between measured and predicted rates of dry N deposition to the urban core may be explained by incomplete collection of gas phase N on surrogate deposition surfaces in this hot and arid environment. The extent of urban enhancement of cations and oC inputs to desert ecosystems appears to be restricted to the urbanized metropolitan area rather than extending far downwind, although a low number of sites make it difficult to resolve this spatial pattern. Nevertheless, wet and dry inputs may be important for biogeochemical cycles in nutrient and carbon-poor desert ecosystems within and near arid cities.