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The aim of this work is to investigate the relationship among rheology, tribology and traditional standardized technological parameters of lithium lubricating greases.

Lubricating greases having the same composition but differing in processing protocols have been manufactured and characterized in order to isolate the rheological behaviour from the formulation.

Some successful empirical correlations between rheological (viscous and viscoelastic) and technological standardized parameters, with the friction factor obtained from a ball‐disc tribometer, have been established in order to elucidate the role of the rheological behaviour of lubricating greases on the friction process. In addition to this, an energetic evaluation of the structural degradation of greases during the friction process has been carried out by performing stress‐growth experiments. Thus, the storage energy density, which is related to the grease capacity to accumulate energy in the elastic deformation, and the limiting energy density, which represents the dissipation of energy in the flow process, have been satisfactorily correlated with the friction factor.

The complex rheological behaviour of lubricating greases, the extreme deformations and the high‐shear stresses resulting in a tribological contact imply that it is difficult to develop a model to describe their behaviour in an elastohydrodynamic lubricating contact.

This paper provides a resource of practical data to be applied in tribological systems.

Lubricants are very complex mixtures of components. To predict their behaviour over a long time it is necessary to make a lot of machinery element tests. This paper tries to give an insight into how lubricants can be estimated in their structure by IR‐microscopy and how this procedure could lead to a short prediction of their long‐time behaviour in time‐ and cost‐expansive machinery element testing.

Greases are non‐Newtonian fluids with a special rheological and tribological behaviour. They have a wide range of applications, for example, ball bearings and gears. This paper reports a study of the reaction of model greases in a tribological contact. The influence of the grease topography has been measured in several tests and the tribological process is modelled. All investigations were done from an energy point of view.

In 2018, the Centers for Disease Control and Prevention (CDC) released the statistic that 1 out of every 59 children had a diagnosis of autism spectrum disorder (ASD). Young children with ASD have unique needs specifically related to the characteristics that impact their communication and social emotional and behavioral development. These unique needs require early and intensive intervention to minimize their lifelong impact. It is important to identify and use evidence-based interventions to help parents support their children at home, and as a continuation of the skills they are being taught in other settings. This chapter will address the prevalence of young children with ASD, the impact and need for family involvement in intervention, and service provision and potential interventions.

The aim of this paper is to characterize some selected formulations based on castor oil and a variety of biogenic thickeners from a tribological point of view and compare them with some traditional lithium greases.

The evolution of the friction coefficient in several tribological tests performed using several ball‐on‐disc configurations and coupling materials was monitored for the different oleogels proposed as biodegradable lubricating greases. Both a rotational ball‐on‐disc classical tribometer designed at MuT laboratory and a nanotribometer were used in rotational and oscillatory modes.

Generally, the use of castor oil‐based formulations potentially applicable as biodegradable lubricating greases provides similar or lower values of the friction coefficient than traditional lithium greases, depending on the nature of thickener agent employed and tribological contact. In all cases, biodegradable formulations provide significantly lower values of the friction coefficient in tribological tests performed in the oscillatory mode. Weak oleogels like those thickened with glyceryl and sorbitan monostearates or acylated chitosan, provide the lowest values of the friction coefficient in every type of configuration or frictional test analysed. Biogrease formulations containing cellulose or chitin derivatives as thickener agents generally yield higher values of the friction coefficient, which may be comparable to those obtained with the reference lithium greases depending on the thickener and tribological configuration. In frictional tests performed in the rotational mode, the inclusion of ethyl cellulose in the formulation yields high values of the friction coefficient, which was attributed to the castor oil viscosity modification exerted by this additive. Wear results depend on the balance between the frictional behaviour, especially in the initial transient regime, and oleogel mechanical stability.

This investigation proposes different new alternatives to replace the traditional thickener agent in lubricating greases with others based on renewable resources in order to obtain a completely biodegradable formulation for different industrial applications.

This paper provides a resource of new practical friction coefficient data as well as a comparative analysis of the tribological response of these new formulations based on biogenic thickeners and other traditional lithium greases.

A rapid increase in global smartphone ownership and digital health technologies offers the potential for mobile phone applications (apps) to deliver mental health interventions. The purpose of this paper is to bring together evidence reporting on mental health mobile apps to gain an understanding of the quality of current evidence, the positive and adverse effects of apps and the mechanisms underlying such effects.

A systematic search was carried out across six databases, for any systematic reviews or meta-analyses conducted up to 2020. Review quality was assessed using the Assessment of Multiple Systematic Reviews.

Across a total of 24 articles, a variety of clinical outcomes were assessed. Most compelling support was shown for apps targeting anxiety symptoms; some evidence favoured the use of apps for depression symptoms. Less evidence was available for the remaining clinical symptoms such as bipolar disorder, schizophrenia, post-traumatic stress disorder, sleep disorders and substance use. Overall, there was limited evidence pertaining to adverse effects and change mechanisms and a lack of quality reporting across a large proportion of included reviews. The included reviews demonstrate the need for further robust research before apps are recommended clinically.

This paper makes a valuable contribution to the current status of research and reviews investigating mental health mobile apps. Recommendations are made for improved adherence to review guidelines and to ensure risk of bias is minimised.

The thixotropy of lubricating grease thickened with lithium 12-hydroxystearate with mineral base oil was investigated. The thixotropy has a significant influence on the flow resistance and pressure drop in the structural components of lubrication systems, which is of major importance as today the latter are being centralized and automated. The paper aims to discuss these issues.

Rheometer studies on thixotropy were carried out and the grease microstructure was visualized using atomic force microscopy (AFM). Total reflection Fourier transform infrared spectroscopy (ATR-FTIR) was used to study the physicochemical interactions which indicate the disintegration and recovery of the grease microstructure.

A qualitative assessment of the physicochemical interactions between lithium soap floccules was made and a theory of the self-ordering effect of lithium 12-hydroxystearate associated molecules during shearing and their aggregation and flocculation during relaxation has been proposed.

Because of the complexity of the disintegration and recovery of the lubricating grease thickener microstructure, there is still limited physical understanding of the mechanism of this process. Therefore, the present research was undertaken to identify the phenomena involved.

The purpose of this article is to explore Maggie Kuhn's theoretical and analytical contributions to social gerontology and more broadly to the advancement of critical and public sociology.

This paper is an theoretical exploration of ageing. Maggie Kuhn's and the Gray Panthers theoretical contributions include analyses of, and related to: identity politics, intersectionality, cultural and media studies and the cognitive sciences, the forces and factors in the developing political economy of ageing including critiques of the ageing enterprise and the medical industrial complex, the sociology of knowledge of gerontology and globalization and world imperialism. The concluding section argues that the post‐retirement career of Maggie Kuhn was one of a Public Sociologist.

Maggie Kuhn fulfils the promise of the Project of Public Sociology, which “is to make visible the invisible, to make the private public, to validate these organic connections as part of our sociological life”. Maggie Kuhn's example moved forward the work of multiple generations of scholars. She lived and produced critical social analyses in pursuit of emancipatory knowledges. Her work is one of the earliest forms, if not the first, of critical pedagogy in gerontology; she promoted and advanced discourses of resistance. Maggie Kuhn was an engaged and outraged, practicing organic intellectual – the epitome of what bell hooks means by “teaching to transgress” and “education as the practice of freedom”. In the 24 years after her involuntary retirement, this was Maggie Kuhn's full‐time transformational agenda.

The paper looks at how the biography of Maggie Kuhn helped to engender the rise of radical social gerontology.

The advent of grocery sales through online channels necessitates that bricks-and-mortar retailers redefine their logistics networks if they want to compete online. Because the general understanding of such bricks-and-clicks logistics systems for grocery is still limited, the purpose of this paper is to analyze the internal logistics networks used to serve customers across channels by means of an exploratory study with retailers from different contexts.

A total of 12 case companies from six European countries participated in this exploratory study. Face-to-face interviews with managers were the primary source for data collection. The heterogeneity of the sample enabled the authors to build a typology of logistics networks in grocery retailing on multiple channels and to understand the advantages of different warehousing, picking, internal transportation and last-mile delivery systems.

Bricks-and-mortar grocery retailers are leveraging their existing logistics structures to fulfill online orders. Logistics networks are mostly determined by the question of where to split case packs into customer units. In non-food logistics, channel integration is mostly seen as beneficial, but in grocery retailing, this depends heavily on product, market and retailer specifics. The data from the heterogeneous sample reveal six distinct types for cross-channel order fulfillment.

The qualitative analysis of different design options can serve as a decision support for retailers developing logistics networks to serve customers across channels.

The paper shows the internal and external factors that drive the decision-making for omni-channel (OC) logistics networks for previously store-based grocery retailers. Thereby, it makes a step toward building a contingency and configuration theory of retail networks design. It discusses in particular the differences between grocery and non-food OC retailing, last-mile delivery systems and market characteristics in the decision-making of retail networks design.