The flatwormMacrostomum lignanofeatures a duo-gland adhesive system that allows it to repeatedly attach to and release from substrates in seawater within a minute. However, little is known about the molecules involved in this temporary adhesion. In this study, we show that the attachment ofM. lignanorelies on the secretion of two large adhesive proteins,M. lignanoadhesion protein 1 (Mlig-ap1) and Mlig-ap2. We revealed that both proteins are expressed in the adhesive gland cells and that their distribution within the adhesive footprints was spatially restricted. RNA interference knockdown experiments demonstrated the essential function of these two proteins in flatworm adhesion. Negatively charged modified sugars in the surrounding water inhibited flatworm attachment, while positively charged molecules impeded detachment. In addition, we found thatM. lignanocould not adhere to strongly hydrated surfaces. We propose an attachment–release model where Mlig-ap2 attaches to the substrate and Mlig-ap1 exhibits a cohesive function. A small negatively charged molecule is secreted that interferes with Mlig-ap1, inducing detachment. These findings are of relevance for fundamental adhesion science and efforts to mitigate biofouling. Further, this model of flatworm temporary adhesion may serve as the starting point for the development of synthetic reversible adhesion systems for medicinal and industrial applications.

In the past many mechanisms of action have been proposed to explain the surfactant‐induced uptake of agrochemicals applied to foliage. These are reviewed briefly and discussed in relation to potential sites of uptake activation, particularly in the light of recent radiochemical work on the foliar uptake behaviour of surfactants on intact plants in the presence or absence of model penetrants and pesticides. The body of evidence available is examined in relation to the many outstanding problems that still exist in understanding the role and use of surfactants as uptake activators in agrochemical formulations.

The development of sodium ion batteries is largely motivated by the growing cost and limited resources of lithium. Titanium dioxide (TiO 2 ), in the form of selforganized and well-oriented nanotube arrays, are considered as a highly attractive anode material for sodium ion batteries, due to their inherent safety, low cost, and structural stability. This work reports on the sodiation and desodiation characteristics of anodically grown, self-organized TiO 2 nanotubes annealed in an Ar/C 2 H 2 atmosphere (TiO 2−x − C). It is found that anatase TiO 2−x −C nanotubes demonstrate substantial self-improving charge storage capacities as cycling proceeds, leading to a specific capacity of 202.2 ± 50.6 mAh g −1 at a current rate of 30 mA g −1 (C/20). Subsequent kinetic analysis reveals a pseudocapacitive contribution which dominates the Na storage process in TiO 2−x −C nanotubes at fast sodiation rates. This pseudocapacitance in TiO 2−x −C nanotubes is found to enable exceptional high-rate capabilities with a specific capacity of 58.4 ± 14.6 mAh g −1 at a current rate of 12 A g −1 (20C).

Interactions occurring during the surfactant‐enhanced foliar uptake of seven model organic compounds were examined using two homogeneous surfactants, hexaethylene glycol monotridecyl ether (C13E6) and hexadecaethylene glycol monododecyl ether (C12E16). Surfactant–compound and compound–surfactant interactions were detected by measurement of their relative uptake rates following application of c. 0·2 μl droplets of the corresponding radiolabelled formulations. The magnitude of surfactant–compound interaction was found to vary according to the physicochemical properties of both the compound and the surfactant, and was influenced by surfactant concentration and target plant species. Interactive and non‐interactive mechanisms, both leading to substantial enhancement of compound uptake, could be identified, but their precise nature could not be elucidated. Although penetration of C13E6 into the site of application appeared to be essential in order to activate the uptake of a compound, substantial absorption of C12E16 was not always required to produce the same effect. The results are discussed in the light of possible sites and modes of action for activator polyoxyethylene surfactant adjuvants.

Composition‐concentration relationships between a series of C13/C14 polyoxyethylene primary alcohol (AE) surfactants and the foliar uptake enhancement of five model neutral organic compounds were examined in factorially designed experiments on wheat (Triticum aestivum L.) and field bean (Vicia faba L.) plants grown under controlled environment conditions. Model compounds were applied to leaves as c.0.2‐μl droplets of 0.5 g litre−1 solutions in aqueous acetone in the absence or presence of surfactants at 0.2, 1 and 5g litre−1. Uptake of the highly water‐soluble compound, methylglucose (log octanol‐water partition coefficient (P) = ‐ 3.0) was best enhanced by surfactants with high E (ethylene oxide) contents (AE15, AE20), whereas those of the lipophilic compounds, WL110547 (log P = 3.5) and permethrin (log P = 6.5), were increased more by surfactants of lower E contents, especially AE6. However, there was little difference between AE6, AE11, AE15 and AE20 in their ability to promote uptake of the two model compounds of intermediate polarity, phenylurea (log P = 0.8) and cyanazine (log P = 2.1). Absolute amounts of compound uptake were also influenced strongly by both surfactant concentration and plant species. Greatest amounts of uptake enhancement were often observed at high surfactant concentration (5 g litre−1) and on the waxy wheat leaves compared with the less waxy field bean leaves. The latter needed higher surfactant thresholds to produce significant improvements in uptake. Data from our experiments were used to construct a simple response surface model relating uptake enhancement to the E content of the surfactant added and to the physicochemical properties of the compound to be taken up. Qualitative predictions from this model might be useful in rationalising the design of agrochemical formulations.