Non‐verbal mate retention behaviour in women and its relation to couple's relationship adjustment and satisfaction

The function of mate retention strategies is to preserve the bond between romantic partners and to prevent desertion, which is also why such behaviours are often elicited by the presence of a potential rival. Most existing studies on mate retention are based on self‐reports, which are prone to various biases. In this study, we observed non‐verbal behaviour of 47 long‐term romantic heterosexual couples during their interview with a female experimenter, whom the women in the couples may have perceived as a potential rival. We measured non‐verbal displays of mate retention tactics (direct guarding, intimacy inducement, appearance enhancement, and love and care display), as well as relationship maintenance strategies of openness and positivity. We expected that relationship quality as reported by both partners in the couple would be positively associated with ‘benefit‐provisioning’ mate retention behaviours and negatively associated with a ‘cost‐inflicting’ mate retention tactic (direct guarding). Relationship quality was assessed by Spanier's Dyadic Adjustment Scale using both the total score of dyadic adjustment and a Dyadic Satisfaction subscale. We found a significant association between both partners' dyadic adjustment and satisfaction and woman's appearance enhancement behaviours (such as self‐touch, hair flip and primp) in the presence of her partner and a potential rival. We also found a negative association between partner's dyadic adjustment and woman's direct guarding of partner using short looks, and a positive association between woman's intimacy‐inducing behaviour using long gaze and her own dyadic satisfaction and her partner's dyadic adjustment. Our results highlight the specific role of female attractiveness in later stages of romantic relationships within the context of mate retention and draw attention to the significance of the use of observational techniques in addition to self‐reports.     

The VGVAPG Peptide Regulates the Production of Nitric Oxide Synthases and Reactive Oxygen Species in Mouse Astrocyte Cells In Vitro

Neurochemical Research - The products of elastin degradation, namely elastin-derived peptides (EDPs), are detectable in the cerebrospinal fluid of healthy individuals and in patients after ischemic...     

Design and synthesis of a stereodynamic catalyst with reversal of selectivity by enantioselective self‐inhibition

Chirality plays a pivotal role in an uncountable number of biological processes, and nature has developed intriguing mechanisms to maintain this state of enantiopurity. The strive for a deeper understanding of the different elements that constitute such self‐sustaining systems on a molecular level has sparked great interest in the studies of autoinductive and amplifying enantioselective reactions. The design of these reactions remains highly challenging; however, the development of generally applicable principles promises to have a considerable impact on research of catalyst design and other adjacent fields in the future. Here, we report the realization of an autoinductive, enantioselective self‐inhibiting hydrogenation reaction. Development of a stereodynamic catalyst with chiral sensing abilities allowed for a chiral reaction product to interact with the catalyst and change its selectivity in order to suppress its formation, which caused a reversal of selectivity over time.     

Fine scale waterbody data improve prediction of waterbird occurrence despite coarse species data

While modelling habitat suitability and species distribution, ecologists must deal with issues related to the spatial resolution of species occurrence and environmental data. Indeed, given that the spatial resolution of species and environmental datasets range from centimeters to hundreds of kilometers, it underlines the importance of choosing the optimal combination of resolutions to achieve the highest possible modelling prediction accuracy. We evaluated how the spatial resolution of land cover/waterbody datasets (meters to 1 km) affect waterbird habitat suitability models based on atlas data (grid cell of 12 × 11 km). We hypothesized that the area, perimeter and number of waterbodies computed from high resolution datasets would explain distributions of waterbirds better because coarse resolution datasets omit small waterbodies affecting species occurrence. Specifically, we investigated which spatial resolution of waterbodies better explain the distribution of seven waterbirds nesting on ponds/lakes with areas ranging from 0.1 ha to hundreds of hectares. Our results show that the area and perimeter of waterbodies derived from high resolution datasets (raster data with 30 m resolution, vector data corresponding with map scale 1:10 000) explain the distribution of the waterbirds better than those calculated using less accurate datasets despite the coarse grain of the species data. Taking into account the spatial extent (global vs regional) of the datasets, we found the Global Inland Waterbody Dataset to be the most suitable for modelling distribution of waterbirds. In general, we recommend using land cover data of a resolution sufficient to capture the smallest patches of the habitat suitable for a given species’ presence for both fine and coarse grain habitat suitability and distribution modelling.     

Egg investment in response to helper presence in cooperatively breeding Tibetan ground tits

Life‐history theory predicts a trade‐off between current and future reproduction to maximize lifetime fitness. In cooperatively breeding species, where offspring care is shared between breeders and helpers, helper presence may influence the female breeders’ egg investment, and consequently, survival and future reproductive success. For example, female breeders may reduce egg investment in response to helper presence if this reduction is compensated by helpers during provisioning. Alternatively, female breeders may increase egg investment in response to helper presence if helpers allow the breeders to raise more or higher quality offspring successfully. In the facultatively cooperative‐breeding Tibetan ground tit Pseudopodoces humilis, previous studies found that helpers improve total nestling provisioning rates and fledgling recruitment, but have no apparent effects on the number and body mass of fledglings produced, while breeders with helpers show reduced provisioning rates and higher survival. Here, we investigated whether some of these effects may be explained by female breeders reducing their investment in eggs in response to helper presence. In addition, we investigated whether egg investment is associated with the female breeder's future fitness. Our results showed that helper presence had no effect on the female breeders’ egg investment, and that egg investment was not associated with breeder survival and reproductive success. Our findings suggest that the responses of breeders to helping should be investigated throughout the breeding cycle, because the conclusions regarding the breeders’ adjustment of reproductive investment in response to being helped may depend on which stage of the breeding cycle is considered.     

Ergosterol and Fusarium mycotoxins content in two maize cultivars under different forms of nitrogen fertilizers

Mycotoxins are secondary metabolites produced by many filamentous fungi, such as Fusarium, and are widespread in nature and can adversely affect almost all organisms. Mycotoxins can be formed in very different conditions such as when plants are growing or in crops that are stored in improper conditions. One of the methods to prevent the formation of mycotoxins in powdered feed is using varieties of appropriate quality and proper mineral fertilization, primarily nitrogen. In this study, the concentration of ergosterol and mycotoxins in the kernels of two maize cultivars from different maturity groups in Poland during the harvest of 2011 and 2012 was investigated using HPLC methods. We aimed to analyse the concentration of ergosterol as a fungal biomass indicator and mycotoxins from two maize cultivars under six different forms of nitrogen fertilizers. The “stay‐green” hybrid ES Paroli was characterized by a significantly lower ergosterol and the ability to accumulate the mycotoxins, compared to the classic cultivar ES Palazzo. The varieties of maize that remain green for a longer time period, the so‐called stay‐green type, are characterized by a different coefficient of nitrogen remobilization compared to the classic hybrids. Their dynamics of growth and accumulation of nutrients indicates a nitrogen fertilization system, indicating that slow‐release fertilizers are potentially more adapted to the cycles of maize vegetation. Hence, compared to the classic variant, the “stay‐green” variety uses nitrogen more effectively from mineral fertilizers. Such hybrids are healthier and remain in good condition for a longer time; therefore, they are characterized by a lower pathogen pressure. Thus, the cultivation of such varieties can be considered as one of the elements of integrated maize production. We observed identical reactions of the studied experimental factors for both vegetation seasons, which indicates the lack of environmental impact on the functioning and interaction of experimental factors.     

Nematode ascaroside enhances resistance in a broad spectrum of plant–pathogen systems

Recognition of specific molecule signatures of microbes, including pathogens, induces innate immune responses in plants, as well as in animals. Analogously, a nematode pheromone, the ascaroside ascr#18, induces hallmark plant defences including activation of (a) mitogen‐activated protein kinases, (b) salicylic acid‐ and jasmonic acid‐mediated defence signalling pathways and (c) defence gene expression and provides protection to a broad spectrum of pathogens. Ascr#18 is a member of an evolutionarily conserved family of nematode signalling molecules and is the major ascaroside secreted by plant–parasitic nematodes. Here, we report the effects of ascr#18 on resistance in four of the major economically important crops: maize, rice, wheat and soybean to some of their associated pathogens. Treatment with low nanomolar to low micromolar concentrations of ascr#18 provided from partial to strong protection in seven of eight plant–pathogen systems tested with viruses, bacteria, fungi, oomycetes and nematodes. This research may have potential to improve agricultural sustainability by reducing use of potentially harmful agrochemicals and enhance food security worldwide.     

Energy conservation characterizes sleep in sharks

Sharks represent the earliest group of jawed vertebrates and as such, they may provide original insight for understanding the evolution of sleep in more derived animals. Unfortunately, beyond a single behavioural investigation, very little is known about sleep in these ancient predators. As such, recordings of physiological indicators of sleep in sharks have never been reported. Reduced energy expenditure arising from sustained restfulness and lowered metabolic rate during sleep have given rise to the hypothesis that sleep plays an important role for energy conservation. To determine whether this idea applies also to sharks, we compared metabolic rates of draughtsboard sharks (Cephaloscyllium isabellum) during periods ostensibly thought to be sleep, along with restful and actively swimming sharks across a 24 h period. We also investigated behaviours that often characterize sleep in other animals, including eye closure and postural recumbency, to establish relationships between physiology and behaviour. Overall, lower metabolic rate and a flat body posture reflect sleep in draughtsboard sharks, whereas eye closure is a poorer indication of sleep. Our results support the idea for the conservation of energy as a function of sleep in these basal vertebrates.