The activities of thermodynamic components of clay minerals corresponding in composition to pyrophyllite, muscovite, paragonite, and margarite were computed from chemical analyses reported in the literature assuming ideal mixing of atoms on homological sites in the minerals. These activities were then used to generate stability fields for smectites, illites, and mixed-layer clays on logarithmic activity diagrams representing equilibrium among minerals and aqueous solutions at 25°C and 1 bar. Comparative analysis indicates that the approach affords close approximation of both mineral and water compositions in geologic systems.

Magnetic active regions on the Sun are harbingers of space weather. Understanding the physics of how they form and evolve will improve space weather forecasting. Our aim is to characterise the surface magnetic field and flows for a sample of active regions with persistent magnetic bipoles prior to emergence. We identified 42 emerging active regions (EARs), in the Solar Dynamics Observatory Helioseismic Emerging Active Region survey (Schunker et al. 2016, A&A. 595, A107), associated with small magnetic bipoles at least one day before the time of emergence. We then identified a contrasting sample of 42 EARs that emerge more abruptly without bipoles before emergence. We computed the supergranulation-scale surface flows using helioseismic holography. We averaged the flow maps and magnetic field maps over all active regions in each sample at each time interval from 2 d before emergence to 1 d after. We found that EARs associated with a persistent pre-emergence bipole evolve to be, on average, lower flux active regions than EARs that emerge more abruptly. Further, we found that the EARs that emerge more abruptly do so with a diverging flow of $(3\pm 0.6) \times 10^{-6}$ s$^{-1}$ on the order of 50–100 ms$^{-1}$. Our results show that there is a statistical dependence of the surface flow signature throughout the emergence process on the maximum magnetic flux of the active region.

Common marmosets, Callithrix jacchus, are widely used by research laboratories and are commonly provided with food in bowls. These centralised, unchallenging sources of food result in high foraging success for low foraging effort. Foraging devices, which require more skill and effort for foraging success, may broaden the behavioural profiles of marmosets by including more elements of their natural ethogram, reflecting improved welfare. The behaviour of eight female common marmosets was examined as a function of four different food distributions: food centrally located in a stationary bowl; food in a bowl that changed location each day; food centrally located in a stationary bowl, in addition to hidden food in a clustered food source (cluster feeder) or hidden food in dispersed food sources (dispersed feeders). Both the cluster and dispersed feeder distributions increased foraging, and there was a trend for reduced scratching and grooming in the presence of the feeders compared with the bowl-only treatments. The cluster feeder increased the amount of time a marmoset spent in a large room annexed to the home rooms more than the dispersed feeders, and this effect was sustained throughout the day after the feeders had been removed. Both feeders increased activity and movements within all areas of the annexed room compared with the bowl-only treatments; therefore, both feeder types improved the welfare of the captive marmosets more than the provision of food bowls.

Chimpanzees (Pan troglodytes) that are kept in captivity come from a wide variety of backgrounds, and a proportion of them have been subjected to maternal separation and social deprivation during development. The long-term effects of such practices have received little investigation. This study investigates whether the removal of infants from their mothers and/or other chimpanzees affects their activity levels and abnormal behaviours later in life. A total of 69 resocialised chimpanzees were studied at six zoos in the United Kingdom. Chimpanzees were categorised into one of three rearing conditions: reared by their mother in a group of conspecifics (MGR); reared with other conspecifics but separated from their mothers (RO); and reared apart from their mother or other conspecifics for a period of time during infancy (RA). Results indicate that ‘socially deprived’ individuals show reduced levels of normal activity, elevated levels of abnormal behaviours and a wider repertoire of abnormal behaviours. These differences were more pronounced in younger individuals, with adults from the three different rearing conditions performing abnormal behaviour patterns at comparable levels. It is concluded that human-rearing, either alone or with conspecifics, influences behaviour through suppression of normal activity levels as a result of separation and elevation of levels of abnormal behaviours as a mechanism for coping with maternal loss and restricted rearing. However, these effects are not irreversible and recovery of ‘normal’ behaviours may occur with access to an enriched social environment.

Ferric heme b (= ferric protoporphyrin IX = hemin) is an important prosthetic group of different types of enzymes, including the intensively investigated and widely applied horseradish peroxidase (HRP). In HRP, hemin is present in monomeric form in a hydrophobic pocket containing among other amino acid side chains the two imidazoyl groups of His170 and His42. Both amino acids are important for the peroxidase activity of HRP as an axial ligand of hemin (proximal His170) and as an acid/base catalyst (distal His42). A key feature of the peroxidase mechanism of HRP is the initial formation of compound I under heterolytic cleavage of added hydrogen peroxide as a terminal oxidant. Investigations of free hemin dispersed in aqueous solution showed that different types of hemin dimers can form, depending on the experimental conditions, possibly resulting in hemin crystallization. Although it has been recognized already in the 1970s that hemin aggregation can be prevented in aqueous solution by using micelle-forming amphiphiles, it remains a challenge to prepare hemin-containing micellar and vesicular systems with peroxidase-like activities. Such systems are of interest as cheap HRP-mimicking catalysts for analytical and synthetic applications. Some of the key concepts on which research in this fascinating and interdisciplinary field is based are summarized, along with major accomplishments and possible directions for further improvement. A systematic analysis of the physico-chemical properties of hemin in aqueous micellar solutions and vesicular dispersions must be combined with a reliable evaluation of its catalytic activity. Future studies should show how well the molecular complexity around hemin in HRP can be mimicked by using micelles or vesicles. Because of the importance of heme b in virtually all biological systems and the fact that porphyrins and hemes can be obtained under potentially prebiotic conditions, ideas exist about the possible role of heme-containing micellar and vesicular systems in prebiotic times.

Fast-growing broiler chickens use pen-space heterogeneously and have low activity levels, related in part to leg problems. The aim of this study was to test the effects of the addition of string and sand trays to rearing pens on the use of space, levels of activity and leg problems. Broiler chickens were reared in 12 pens (40 birds per pen). Drinkers and feeders only were present in the six control pens (C group), whereas the six other pens were enriched (E group) with two sand trays and string. Behaviour was recorded by scan and focal sampling on days 2-3, 13-14, 23-24 and 34-35. Bodyweight, the occurrence of tarsal deformities and the composition of tibiotarsi were measured on day 37. Chickens from the E group spent more time and stood more often in the area enriched with sand than did the g group birds. ghickens in the E group foraged in the sand throughout the rearing period, and their foraging activities were greater than those of the C group birds. They had little interest in the strings. Locomotor activity during standing bouts was enhanced in the E group on days 2-3 only. Bodyweight at day 37, the occurrence of tarsal deformities and the composition of tibiotarsi were not significantly different between groups. These results indicate that sand could attract chickens into areas that are usually rarely used, which may reduce problems resulting from their heterogeneous distribution. However, the results also indicate the difficulty of stimulating locomotion.

Accelerometers are used to remotely monitor activity in various species in studies that quantify pain, document behavioural patterns, and measure individual activity differences. Studies validating accelerometers typically quantify various active states; however, targeting states specific to periods of inactivity, such as sitting, sleeping, and standing, has the potential to more accurately quantify inactive behaviours commonly associated with behavioural changes related to pain, sickness, or injury. Our objectives were two-fold: first, validate a commercially available accelerometer (Actical®) for quantifying inactivity in laying hens and, second, compare inactivity levels between hens with severely fractured keel bones and hens with minimal to no keel damage. Correlation between the inactivity level as measured by the accelerometer compared to live, focal observation of stationary, inactive behaviours was high; therefore, the Actical® accurately quantifies inactive states in laying hens. Following validation, the Actical® accelerometer was used to quantify inactivity level differences between hens with or without keel-bone damage. Severely fractured hens spent less time motionless, than hens with minimal to no keel damage. Further investigation into inactivity differences related to keel status before and after acquisition of keel fractures is warranted. Use of the accelerometer has the potential to improve animal welfare research by quantifying the effect of pain or sickness on activity level, mapping daily activity patterns, and measuring individual differences in general activity.