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Aim: Diverticular disease is an increasingly common problem in Western society with a variety of treatment options for those presenting with acute diverticulitis, dependent on clinical presentation. Additionally, there is significant international variability in the index management, and few published data on real‐world clinical practice. The aim of DAMASCUS is to identify areas of practice variability and their potential association with differences in short‐ and medium‐term clinical outcomes. Methods and analysis: DAMASCUS is an international, collaborative, prospective observational study, recruiting patients from over 200 sites across six continents. The study opened in October 2020, with a rolling start. Identification of new sites ceased in February 2021 and data collection will cease in August 2021. All adult patients diagnosed with acute diverticulitis (radiologically or intra‐operatively) at each participating centre will be included. The primary objective of DAMASCUS is to assess for national and international variability in the presentation and index management of acute diverticulitis (medical, interventional radiology and surgical). Secondary objectives include assessing 30‐day and 6‐month clinical outcome data (readmission, re‐intervention, morbidity and mortality) and variations in surgical procedures for those undergoing surgery. All data will be recorded and managed using a secure REDCap electronic data capture tool and analysed using Stata (SE) version 16.1. The results will be reported in accordance with the STROBE statement. Conclusion: By analysing variations in the management of acute diverticulitis and the subsequent outcomes, DAMASCUS will be an important step towards identifying optimal care for patients with diverticulitis. [ABSTRACT FROM AUTHOR]

We recently reported on the strong interactions of zoospores of the green alga, Ulva linzawith an arginine-rich oligopeptide self-assembled monolayer (SAM) [Biofouling2008, 24, 303−312], where the arginine-rich peptide induced not only high spore settlement, but also a form of abnormal settlement, or “pseudo-settlement”, whereby a proportion of spores do not go through the normal process of surface exploration, adhesive exocytosis, and loss of flagella. Further, it was demonstrated that both the total number of settled spores and the fraction of pseudosettled spores were related to the surface density of the arginine-rich peptide. Here we present a further investigation of the interactions of zoospores of Ulvawith a set of oligomeric, de novodesigned, arginine-rich peptides, specifically aimed to test the effect of peptide primary structure on the interaction. Via variations in the peptide length and by permutations in the amino acid sequences, we gain further insight into the spore−surface interactions. The interpretation of the biological assays is supported by physicochemical characterization of the SAMs using infrared spectroscopy, ellipsometry, and contact angle measurements. Results confirm the importance of arginine residues for the anomalous pseudosettlement, and we found that settlement is modulated by variations in both the total length and peptide primary structure. To elucidate the causes of the anomalous settlement and the possible relation to peptide−membrane interactions, we also compared the settlement of the “naked” zoospores of Ulva(which present a lipoprotein membrane to the exterior without a discrete polysaccharide cell wall), with the settlement of diatoms (unicellular algae that are surrounded by a silica cell wall), onto the peptide SAMs. Cationic SAMs do not notably affect settlement (attachment), adhesion strength, or viability of diatom cells, suggesting that the effect of the peptides on zoospores of Ulvais mediated via specific peptide−membrane interactions. [ABSTRACT FROM AUTHOR]

Identification of settlement cues for marine fouling organisms opens up new strategies and methods for biofouling prevention, and enables the development of more effective antifouling materials. To this end, the settlement behaviour of zoospores of the green alga Ulva linza onto cationic oligopeptide self-assembled monolayers (SAMs) has been investigated. The spores interact strongly with lysine- and arginine-rich SAMs, and their settlement appears to be stimulated by these surfaces. Of particular interest is an arginine-rich oligopeptide, which is effective in attracting spores to the surface, but in a way which leaves a large fraction of the settled spores attached to the surface in an anomalous fashion. These 'pseudo-settled' spores are relatively easily detached from the surface and do not undergo the full range of cellular responses associated with normal commitment to settlement. This is a hitherto undocumented mode of settlement, and surface dilution of the arginine-rich peptide with a neutral triglycine peptide demonstrates that both normal and anomalous settlement is proportional to the surface density of the arginine-rich peptide. The settlement experiments are complemented with physical studies of the oligopeptide SAMs, before and after extended immersion in artificial seawater, using infrared spectroscopy, null ellipsometry and contact angle measurements. [ABSTRACT FROM AUTHOR]

The swimming patterns of zoospores of the green alga Ulva linza in the vicinity of a surface were investigated by digital in-line holography. Full 3D motion patterns were retrieved from measurements and the traces obtained were compared with known swimming patterns of spores of the brown alga Hincksia irregularis and the green alga Ulva linza as seen in a conventional optical microscope. Quantitative information such as swimming velocity was calculated from the 3D traces. The results demonstrate the potential of digital in-line holography to image and quantify exploratory patterns of behavior of motile spores close to surfaces. This technique can give detailed insight into mechanisms of surface colonization by spores and larvae of fouling organisms in response to changes in surface properties. [ABSTRACT FROM AUTHOR]

Driver distraction is a safety-critical issue that has been bought to greater public attention with the recent developments of more advanced driver support systems (DSS), e.g. navigation systems. Such systems have the potential to distract drivers significantly from the primary task of controlling their vehicle, potentially resulting in an accident. DSS developers need to be able to assess distraction potential in the early stages of design. In this respect, the occlusion technique and its associated measures are claimed to be reliable indicators of potential visual demand. In particular, it has been argued that the technique provides more information than other economical methods based on task time whilst stationary (static task time), such as the ‘15-second rule’. To investigate these assertions, a study compared results from an occlusion assessment and a road-based assessment. Sixteen drivers carried out two tasks using two user-interfaces under three conditions: statically, full vision, statically, restricted vision (occlusion), and whilst driving. Occlusion was found to be a valid technique. In particular, it may be used to distinguish between tasks based on their level of visual demand. It is concluded that occlusion offers advantages over other methods but requires a robust prototype for results to be meaningful. [ABSTRACT FROM AUTHOR]

The optimal ratio of tryptophan (Trp):lysine (Lys) relative to the ratio of threonine (Thr):Lys was studied in 288 crossbred (Cambrough 15 × Canabrid) nursery pigs from 7.1 to 15.6 kg BW. Treatments were arranged in a 3 × 3 factorial with three calculated ratios of true digestible Thr:Lys (0.55, 0.60, or 0.65) in combination with three Trp:Lys ratios (0.145, 0.170, or 0.195). Treatments were replicated with eight pens of four pigs each. The experiment lasted 28 day with Phase II (222.6 g CP and 11.9 g true digestible Lys/kg diet, initially 24 day of age and 7.1 kg BW) and Phase III (196.2 g CP and 10.1 kg true digestible Lys/kg diet, initially 38 day of age and 9.8 kg BW) diets each fed for 14 day. Threonine by Trp interactions were observed for average daily gain during each period, and for daily feed intake during Phase III and overall. Generally, Trp addition linearly increased gain and feed intake at a Thr:Lys ratio of 0.60 and 0.65 but not at a Thr:Lys ratio of 0.55. Gain:feed was increased linearly with increasing levels of Trp during both periods. There were no main effects of Thr in either time period or overall. Overall, optimal performance was obtained in pigs fed the true digestible Trp:Lys ratio of 0.195 at Thr:Lys ratios 0.60 or 0.65. These results indicate that Trp:Lys ratios above 0.195 may be needed to maximize performance in diets containing wheat and barley. [ABSTRACT FROM AUTHOR]

Fouling species produce adhesive polymers during the settlement, adhesion and colonization of new surfaces in the marine environment. The present paper tests the hypothesis that enzymes of the appropriate specificity may prevent biofouling by hydrolysing these adhesive polymers. Seventeen commercially available enzyme preparations designed originally for bulk use in a range of end-use applications were tested for their effects on the settlement and/or adhesion of three major fouling species, viz. the green alga Ulva linza , the diatom Navicula perminuta and the barnacle Balanus amphitrite . The serine-proteases were found to have the broadest antifouling potential reducing the adhesion strength of spores and sporelings of U. linza , cells of N. perminuta and inhibiting settlement of cypris larvae of B. amphitrite . Mode-of-action studies on the serine-protease, Alcalase, indicated that this enzyme reduced adhesion of U. linza in a concentration-dependent manner, that spores of the species could recover their adhesive strength if the enzyme was removed and that the adhesive of U. linza and juvenile cement of B. amphitrite became progressively less sensitive to hydrolysis as they cured. [ABSTRACT FROM AUTHOR]