Critically engineered stiffness and strength of a scaffold are crucial for managing maladapted stress concentration and reducing stress shielding. At the same time, suitable porosity and permeability are key to facilitate biological activities associated with bone growth and nutrient delivery. A systematic balance of all these parameters are required for the development of an effective bone scaffold. Traditionally, the approach has been to study each of these parameters in isolation without considering their interdependence to achieve specific properties at a certain porosity. The purpose of this study is to undertake a holistic investigation considering the stiffness, strength, permeability, and stress concentration of six scaffold architectures featuring a 68.46–90.98% porosity. With an initial target of a tibial host segment, the permeability was characterised using Computational Fluid Dynamics (CFD) in conjunction with Darcy's law. Following this, Ashby's criterion, experimental tests, and Finite Element Method (FEM) were employed to study the mechanical behaviour and their interdependencies under uniaxial compression. The FE model was validated and further extended to study the influence of stress concentration on both the stiffness and strength of the scaffolds. The results showed that the pore shape can influence permeability, stiffness, strength, and the stress concentration factor of Ti6Al4V bone scaffolds. Furthermore, the numerical results demonstrate the effect to which structural performance of highly porous scaffolds deviate, as a result of the Selective Laser Melting (SLM) process. In addition, the study demonstrates that stiffness and strength of bone scaffold at a targeted porosity is linked to the pore shape and the associated stress concentration allowing to exploit the design freedom associated with SLM.

Lattice structure based morphologically matched scaffolds is rapidly growing facilitated by developments in Additive Manufacturing. These porous structures are particularly promising due to their potential in reducing stress shielding and maladapted stress concentration. Accordingly, this study presents Extra Low Interstitial (ELI) Titanium alloy based morphological scaffolds featuring three different porous architecture. All scaffolds were additively manufactured using Selective Laser Melting from Ti6Al4V ELI with porosities of 73.85, 60.53 and 55.26% with the global geometry dictated through X-Ray Computed Tomography. The elastic and plastic performance of both the scaffold prototypes and the bone section being replaced were evaluated through uniaxial compression testing. Comparing the data, the suitability of the Maxwell criterion in evaluating the stiffness behaviour of fully porous morphological scaffolds are carried out. The outcomes show that the best performing scaffolds presented in this study have high strength (169 MPa) and low stiffness (5.09 GPa) suitable to minimise stress shielding. The matching morphology in addition to high porosity allow adequate space for flow circulation and has the potential to reduce maladapted stress concentration. Finally, the Electron Diffraction X-ray analysis revealed a small difference in the composition of aluminium between the particle and the bonding material at the scaffold surface.

Humans and their associated anthropogenic factors may strongly affect the demographics, activity, and fragmentation of wild animal populations. Yet, the degree and nature of such impact on indicators of animals’ social relationships remain largely under-investigated, despite the well-documented importance of strong social ties for an individuals’ health and fitness. Here, we examined whether interactions with humans may affect core aspects of social life in a primate species, by constraining the time available for individuals to engage in social interactions. Specifically, we predicted that individuals who spent more time monitoring or interacting with humans reduce their time socializing with conspecifics (i.e., the time constraints hypothesis). Alternatively, human presence may result in increased levels of stress, leading to an increase in social behaviours which serve as a coping mechanism (i.e., the social stress hypothesis). We collected data between September 2016 and September 2017 on four groups of long-tailed macaques in Malaysia at two sites with differing levels of human impact. In support of the time constraints hypothesis, we found that at the site with moderate human impact, monkeys who monitored human activity more frequently engaged less often in grooming. In contrast, at the site with high human impact, we found evidence supporting the social stress hypothesis, as indicators of stress were positively associated with social interactions, although we could not link them to the presence of humans. Our results suggest that the nature of human impact on macaques’ social behaviour is dependent upon the intensity of human activity and interaction with the macaques. These findings therefore provide insights into how humans may influence individual fitness and group social structure in animals living in an anthropogenic environment. More broadly, our results may lead to a better understanding of animal behaviour in anthropogenic environments, implementing conservation and population management strategies, and mitigating human-wildlife conflict.

This paper primarily discusses the assessment of stray DC and AC-induced corrosion phenomena on steel fibres and the analysis of the main influencing parameters. Instrumental methods in electrochemistry including Tafel polarization, Cyclic Potentiodynamic (CP) polarization and Electrochemical Impedance Spectroscopy (EIS) were used to assess the corrosion resistance of steel fibres which has great potential to replace conventional steel reinforcement in railway tunnel construction. The analytical model based on electric circuit modelling indicates that concrete containing discrete steel fibres has an inherent corrosion resistance to stray AC interference due to the electrical double layer developed on the surface.

In humans, infants respond positively to slow, gentle stroking—processed by C-tactile (CT) nerve fibers—by showing reductions in stress and increases in eye contact, smiling, and positive vocalizations. More frequent maternal touch is linked to greater activity and connectivity strength in social brain regions, and increases children’s attention to and learning of faces. It has been theorized that touch may prime children for social interactions and set them on a path towards healthy social cognitive development. However, less is known about the effects of touch on young infants’ psychological development, especially in the newborn period, a highly sensitive period of transition with rapid growth in sensory and social processing. It remains untested whether newborns can distinguish CT-targeted touch from other types of touch, or whether there are benefits of touch for newborns’ social, emotional, or cognitive development. In the present study, we experimentally investigated the acute effects of touch in newborn monkeys, a common model for human social development. Rhesus macaques (Macaca mulatta), like humans, are highly social, have complex mother-infant interactions with frequent body contact for the first weeks of life, making them an excellent model of infant sociality. Infant monkeys in the present study were reared in a neonatal nursery, enabling control over their early environment, including all caregiver interactions. One-week-old macaque infants (N = 27) participated in three 5-minute counter-balanced caregiver interactions, all with mutual gaze: stroking head and shoulders (CT-targeted touch), stroking palms of hands and soles of feet (Non-CT touch), or no stroking (No-touch). Immediately following the interaction, infants watched social and nonsocial videos and picture arrays including faces and objects, while we tracked their visual attention with remote eye tracking. We found that, during the caregiver interactions, infants behaved differently while being touched compared to the no-touch condition, irrespective of the body part touched. Most notably, in both touch conditions, infants exhibited fewer stress-related behaviors—self-scratching, locomotion, and contact time with a comfort object—compared to when they were not touched. Following CTtargeted touch, infants were faster to orient to the picture arrays compared to the other interaction conditions, suggesting CT-targeted touch may activate or prime infants’ attentional orienting system. In the No-touch condition infants attended longer to the nonsocial compared to the social video, possibly reflecting a baseline preference for nonsocial stimuli. In contrast, in both touch conditions, infants’ looked equally to the social and nonsocial videos, suggesting that touch may influence the types of visual stimuli that hold infants’ attention. Collectively, our results reveal that newborn macaques responded positively to touch, and touch appeared to influence some aspects of their subsequent attention, although we found limited evidence that these effects are mediated by CT fibers. These findings suggest that newborn touch may broadly support infants’ psychological development, and may have early evolutionary roots, shared across primates. This study illustrates the unique insight offered by nonhuman primates for exploring early infant social touch, revealing that touch may positively affect emotional and attentional development as early as the newborn period.

© 2019 Elsevier Ltd Natural bioactive materials with wound healing properties such as curcumin are attracting interest due to the emergence of resistant bacterial strains. The hydrophobicity of curcumin has been counteracted by using solubility enhancing cyclodextrins. Hydrogels facilitate wound healing due to unique properties and 3D network structures which allows encapsulation of healing agents. In this study, biosynthetic cellulose produced by Gluconacetobacter xylinus (ATCC 23770) was loaded with water soluble curcumin:hydroxypropyl-β-cyclodextrin supramolecular inclusion complex produced by a solvent evaporation method to synthesise hydrogel dressings. The ratios of solvents to solubilise curcumin and hydroxypropyl-β-cyclodextrin were tested for the production of the inclusion complex with optimum encapsulation efficacy. The results confirmed that hydroxypropyl-β-cyclodextrin enhanced the aqueous solubility of curcumin and allowed loading into bacterial cellulose hydrogels. These hydrogels were characterised for wound management applications and exhibited haemocompatability, cytocompatability, anti-staphylococcal and antioxidant abilities and therefore support the potential use of the curcumin:hydroxypropyl-β-cyclodextrin-loaded-bacterial cellulose as hydrogel dressings.

Current authentication protocols seek to establish authenticated sessions over insecure channels while maintaining a small footprint considering the energy consumption and computational overheads. Traditional authentication schemes must store a form of authentication data on the devices, putting this data at risk. Approaches based on purely public/private key infrastructure come with additional computation and maintenance costs. This work proposes a novel noninteractive zero knowledge (NIZKP) authentication protocol that incorporates the limiting factors in IoT communication devices and sensors. Our protocol considers the inherent network instability and replaces the ZKP NP-hard problem using the Merkle tree structure for the creation of the authentication challenge. A series of simulations evaluate the performance of NIZKP against traditional ZKP approaches based on graph isomorphism. A set of performance metrics has been used, namely the channel rounds for client authentication, effects of the authentication processes, and the protocol interactions to determine areas of improvements. The simulation results indicate empirical evidence for the suitability of our NIKP approach for authentication purposes in resourceconstrained IoT environments.

Capping failure, edge chipping, and non-uniform mechanical properties of convexfaced pharmaceutical tablets are common problems in pharma industry. In this paper, Finite Element Modelling (FEM) and Design of Experiment (DoE) techniques are adopted to find the optimal shape of convex-faced (CF) pharmaceutical tablet which has more uniform mechanical properties and less capping and chipping tendency. The effects of the geometrical parameters and friction on the compaction responses of convex-faced pharmaceutical tablets were first identified and analysed. The finite element model of the tabletting process was generated using the implicit code (ABAQUS) and validated against experimental measurements. Response Surface Methodology (RSM) was employed to establish the relationship between the design variables, represented by the geometrical parameters and the friction coefficient, and compaction responses of interest including residual die pressure, the variation of relative density within the tablet, and the relative shear stress of the edge of the tablet. A statistical-based optimisation approach is then employed to undertake shape optimisation of CF tablets. The obtained results demonstrated how the geometrical parameters of CF tablet and the friction coefficient have significant effects on the compaction behaviour and quality of the pharmaceutical tablet.

Context The 25th anniversary of the founding of the UK chapter of the International Association for Landscape Ecology (ialeUK) was marked in 2017. Objectives To assess trends in UK landscape ecology research over ialeUK’s first 25 years, to compare these trends to changes elsewhere in the world, and to consider how ialeUK can continue to support landscape ecology research and practice. Methods A database of conference abstracts was compiled and examined in combination with a questionnaire that surveyed existing and former active members of ialeUK. Results Across 1992–2017 we observe noticeable trends including the declining roles of statutory bodies, the development of the ecosystem services concept, and a decrease in use of empirical methods. Analysis of questionnaire results highlighted four key areas: Developing new researchers; Facilitating conferences for networking, learning and discussion; Linking policy with practice; and Driving the continued growth of landscape ecology as a discipline. Challenges were also noted, especially regarding the adoption of a wider understanding of landscape ecological principles in management. Conclusions Increases in qualitative research, decreases in studies explicitly examining connectivity/fragmentation and an absence of landscape genetics studies in the UK are seemingly distinct from US landscape ecology and elsewhere around the world, based on published accounts. ialeUK has had success in increasing the role of landscape ecology in policy and practice, but needs to continue to aim for improved collaboration with other landscape-related professional bodies and contributions to wider sustainability agendas.

Academic psychology in the USA is a gender success story in terms of overturning its early male dominance but there are still relatively few senior female psychology researchers. To assess whether there are gender differences in citation impact that might help to explain either of these trends, this study investigates psychology articles since 1996. Seven out of eight Scopus psychology categories had a majority of female first-authored journal articles by 2018. From regression analyses of first and last author gender and team size, female first authors associate with a slightly higher average citation impact, but extra authors have a ten times stronger association with higher average citation impact. Last author gender has little association with citation impact. Female first authors are more likely to be in larger teams and if team size is attributed to the first author’s work, then their apparent influence of female first authors on citation impact doubles. Whilst gender differences in average citation impact are too small to account for gender-related trends in academic psychology, they warn that male dominated citation-based ranking lists of psychologists do not reflect the state of psychology research today.