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Inspired by the high-friction performance of the soft toe pads of tree frogs, this study aims to investigate the effect of elastic deformation on the lubrication properties of squeezing films inside soft tribocontacts with microstructured surface under wet conditions.

A one-dimensional hydrodynamic extrusion model was used to study the film lubrication characteristics of conformal contact. The lubrication characteristics of the extruded film, including load-carrying capacity, liquid flow and surface elastic deformation, were obtained through the simultaneously iterative solution of the fluid-governing and deformation equations.

The results show that the hydrodynamic pressure is approximating parabolically and symmetrically distributed in the contact area, and the peak value appears in the center of the extrusion surface. Elastic deformation increases the thickness of the liquid film, weakens the bearing capacity and homogenizes the liquid flow rate of inside soft friction contact. The magnitude of this effect greatly increases as the initial liquid film thickness decreases. Moreover, the elastic deformation directly affects the average film thickness of the extrusion contact. Narrow and shallow microchannels are found to result in a more prominent elastic deformation on the microstructured soft surface.

These results present a design for soft tribocontacts suitable for submerged or wet environments involving high friction, such as wiper blades, in situ flexible electrons and underwater robots.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2024-0049/

The lubricating fluid stored in the porous matrix will spontaneously exude to supplement the lubricating film in the damaged area, thus ensuring the long-term self-lubricating function of the porous surface. To reveal the repair mechanism of oil film, it is necessary to understand the flow characteristics of oil in micropores. The purpose of this study guides the design of micropore structure to realize the rapid exudation of oil to the porous surface and the rapid repair of the lubricating film.

In this paper, cylindrical orifice, convergent orifice and divergent orifice were studied. The numerical model of lubricating oil exudation in micropores was established. The distribution characteristics of oil pressure, velocity and three-phase contact line in the process of oil exudation were investigated. The effects of different orifice shapes and orifice structure parameters on the pinning and spreading characteristics of oil droplet were analyzed. Then the internal mechanisms of oil droplet formation and spread on the orifice surface were summarized.

The results show that during the process of oil exudation, the three-phase contact line of the oil drop is pinned once at the edge of the cylindrical and convergent orifice. Compared with the three orifice structures, the inlet pressure of the oil drop is low, and the oil velocity at the pinning point is stable in the divergent orifice. Resulting in favorable oil exudation. It is easier for oil droplet to depin by appropriately reducing the wall wetting angle, increasing the aperture or controlling the wall inclination angle. Ensure the self-healing and long-lasting lubrication film of porous oil-bearing surfaces.

The effect of pore structure on the flow behavior of lubricating fluid has always been concerned. But the mechanism by which different orifice shape affect the pinning behavior of oil droplets is not yet clear, which is crucial for understanding the self-healing mechanism of oil films on porous surfaces. It is meaningful to analyze the mechanism of oil exudation and spreading on the porous surface of oil in the special orifice, to optimize the design of the orifice structure.

Orifice shape has influence on internal flow field parameters. There is no report on the influence of orifice shape on the film formation process of oil seepage and diffusion from pores. The effects of different orifice shapes and orifice structure parameters on the characteristics of oil droplet pinning and diffusion were studied.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0118/

The traditional VeoVa10-VAc copolymer latex, which prepared via the emulsion polymerization of the mixed monomers of VAc and VeoVa10, has the poor water resistance and thermal stability because of the migration of the conventional emulsifier molecules and the low bond energy of C-C bond. The purpose of this work is that the fluorinated monomer is used to modify the latex. The film of the resultant latex has the C-F bond with high bond energy and low surface energy, which can effectively improve the heat resistance and water resistance of the resultant film. In addition, the reactive emulsifier is used to replace the conventional emulsifier. The drawbacks of the conventional emulsifier molecules migrate and desorb can be avoided when the polymer latex is stored, thereby also improving the water resistance.

The modified VAc-VeoVa10 latex has been successfully synthesized via the semi-continuous seeded emulsion polymerization, which VAc and VeoVa10 is used as the main monomers and HFMA was used as the functional monomer. KPS and reactive surfactants of SE-10 were used as the initiator and emulsifier, respectively. The structure of resultant latex film was characterized by Fourier transform infrared spectroscopy (FTIR). The latex films were tested by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and contact angle (CA). The particle size and its distribution of the latex were measured by the nano particle size analyzer.

The factors that had an influence on the properties of the latex and the film were investigated in detail. The stability of the resultant latex is good. The average particles of the latex and its distribution are small and uniform, respectively. In comparison with the conventional latex film, the thermal stability and hydrophobicity of the resultant latex film are improved obviously.

The resultant latex can be used in both the waterborne interior and exterior wall coatings, pickering stabilized waterborne polymer dispersions, polymer powders, environmentally friendly polymer-modified waterproof mortar and other fields, which can be satisfied with the high demand of thermal stability and hydrophobicity.

The modification of poly (VAc-VeoVa10) by reactive surfactant and fluorinated monomer is seldom reported. In this study, the fluorinated poly (VAC-VeoVa) latex is prepared via the reactive surfactants, which VAc and VeoVa10 is used as the main monomers and hexafluorobutyl methacrylate is used as the functional monomer. Potassium persulfate (KPS) and allyl nonyl phenoxy propyl alcohol polyoxyethylene ether ammonium sulfate are used as the initiator and emulsifier, respectively.

In this study, I use currere to examine excessive entitlement in my own high school education. By “excessive entitlement,” I emphasize teachers' actions and systemic conditions related to an excessive educational mindset justifying (and manifesting) self-infallibility. Teachers displaying excessive entitlement might take for granted, for example, the correctness of their actions, closing self-awareness, and more equitable relations with others (especially students). On a structural level, it includes, for example, societal norms, school policies, educational traditions, and often laws. Specifically, I present findings examining three levels of curriculum – the formal or explicit, the implicit or hidden, and the null or present/absent. I offer my own story as a case study of how schools and teachers may silence and erase student identity and culture as well as how more inclusive and dialogic teaching approaches (and methods of inquiry) can counteract and offer alternatives to such oppressive forces. My framework includes professional ethics, moral ethics, and social justice ethics. Looking back at my history as a gay high school student, I discovered that my school's explicit curriculum provided teachers with a safe haven for bigotry and hostility toward LGBTQ students (as well as female students and students of color), and its hidden curriculum projected messages that privileged such a curriculum (and denigrated epistemologies more on the margin). It was only in the null curriculum that I began to experience a sense of liberation and inclusion and an awareness of the multiplicity of epistemology and ontology.

Food marketing has long been recognized to influence food preferences, consumption and health, yet little is known about the nature and extent of food marketing to young adults – especially with respect to their real-world encounters with food marketing and the appeals they find persuasive. This study aims to engage young adults to explore the persuasive power of food marketing and its platforms of exposure.

Participatory research with 45 young adults, who used a specially designed mobile app to capture the food marketing they encountered for seven days, including information on brand, product, platform and “power” (i.e. the specific techniques that made the advertisement persuasive).

A total of 618 ads were captured for analysis. Results revealed the dominance of digital platforms (especially Instagram, comprising 43% of ads), fast food and beverage brands (48% of ads) and the top persuasive techniques of visual style, special offer and theme.

This study uniquely draws from framing theory to advance the notions of selection and salience to understand food marketing power. It is the first study of its kind to provide a comprehensive look at the platforms and persuasive techniques of food marketing to adults as selected, captured and tagged by participants. It provides timely insights into young adults and food marketing to adults, including where it is encountered, the (generally unhealthy) brands and products promoted and how it is made meaningful.

Fairy tales and their movie counterparts have, for decades, been a means of socialising children and audiences regarding gender (e.g., Shewmaker, 2015; Whitley, 2013). Specifically, Disney movies that portray fairy tales have strongly influenced how young children learn gender roles and gendered behaviours, yet deeper examination is needed of how Disney portrayals of masculinities have evolved among these films and across character type to understand how Disney may be reflecting or impacting dominant representations of masculinity that privilege certain identities and characteristics over others (Brode, 2016). While previous work has examined Pixar films as socio-culturally meaningful for representations of boyhood that remain grounded in traditional, hegemonic notions of masculinity (Wooden & Gillam, 2014), this chapter adds to the body of work by employing a critical content analysis of Disney films from Snow White and the Seven Dwarfs to Disney's most recent addition of Strange World to answer the questions about how masculinities are portrayed. Through answering these questions of evolved representation throughout close to a century amount of work, we contribute to scholarship that attempts to understand media influences on boyhood culture, which is considered in crisis due to overemphasised representations of powerful, strong male characters that hide their emotions (Brode, 2016; Wooden & Gillam, 2014).

This study aims to improve detection efficiency of fluorescence biosensor or a graphene field-effect transistor biosensor. Graphene field-effect transistor biosensing and fluorescent biosensing were integrated and combined with magnetic nanoparticles to construct a multi-sensor integrated microfluidic biochip for detecting single-stranded DNA. Multi-sensor integrated biochip demonstrated higher detection reliability for a single target and could simultaneously detect different targets.

In this study, the authors integrated graphene field-effect transistor biosensing and fluorescent biosensing, combined with magnetic nanoparticles, to fabricate a multi-sensor integrated microfluidic biochip for the detection of single-stranded deoxyribonucleic acid (DNA). Graphene films synthesized through chemical vapor deposition were transferred onto a glass substrate featuring two indium tin oxide electrodes, thus establishing conductive channels for the graphene field-effect transistor. Using π-π stacking, 1-pyrenebutanoic acid succinimidyl ester was immobilized onto the graphene film to serve as a medium for anchoring the probe aptamer. The fluorophore-labeled target DNA subsequently underwent hybridization with the probe aptamer, thereby forming a fluorescence detection channel.

This paper presents a novel approach using three channels of light, electricity and magnetism for the detection of single-stranded DNA, accompanied by the design of a microfluidic detection platform integrating biosensor chips. Remarkably, the detection limit achieved is 10 pm, with an impressively low relative standard deviation of 1.007%.

By detecting target DNA, the photo-electro-magnetic multi-sensor graphene field-effect transistor biosensor not only enhances the reliability and efficiency of detection but also exhibits additional advantages such as compact size, affordability, portability and straightforward automation. Real-time display of detection outcomes on the host facilitates a deeper comprehension of biochemical reaction dynamics. Moreover, besides detecting the same target, the sensor can also identify diverse targets, primarily leveraging the penetrative and noninvasive nature of light.

Like most in education, I rarely take the opportunity to question and slow down enough to reflect on ideas and intentionally notice the subtle shifts in my thoughts. Life is hurried, and finding quiet reflective moments is difficult but not impossible. Encouraged to confront experiences of excessive entitlement in relation to the social, cultural, and political world, I learned that as with much in life there is a give and take, a negotiation of sorts, which if allowed leads to understanding. The interconnectedness of practitioners' varying experiences with administrators and educational policies raises the question of who affects whom and causes me to reflect on my research questions: 1. What is my relationship with excessive teacher entitlement? 2. Am I implicit in its production? If so, how and why?

In this chapter, I reflect on my cognitive and emotional relationship with excessive entitlement as an embodied experience through autoethnography methodology and phenomenology. By troubling or worrying the notion of excessive entitlement, I confront my beliefs through conversations with student teachers and veteran teachers, examining the interconnectedness of how people are implicit in its production. As a researcher and participant, the theoretical underpinnings of phenomenology allow me to orient myself to my lived experiences as an art teacher, teacher leader, and faculty member and leader at a private university. Pulling from journal entries, emails, written “ponderings,” noted conversations, and memory, data support the notion that excessive entitlement occurs at all levels in education, and awareness is the first step toward understanding.

Children's film and fiction often portray a witch as either an evil hag or an incompetent older woman yet when the male witch is within the narrative, he is named Sorcerer or Wizard, suggesting therefore that (unlike the hag) age and gender is not a factor when performing witchcraft. Moreover, the male witch identity is introduced from the position of empowerment and competency rather than prejudice. Witch identities are gendered, and the male witch is underappreciated and overlooked by the historical identity of the female witch.

This chapter analyses how the male witch is presented in selected children's film and fiction through the frameworks of Hegemonic, Hybrid, and Mosaic Masculinity. Hegemonic Masculinity demonstrates the toxic performance of the male witch, indicating to readers and audiences that to be male and a witch, a heterosexual man must be cruel and manipulative. Hybrid Masculinities relate to some patriarchal behaviours such as violent outbursts, that also blend with more empathetic and emotional behaviours. Mosaic Masculinity presents the male witch in a way that is fluid and disrupts the binary of Hegemonic and Hybrid Masculinity.

This chapter acknowledges the absence of presence of the male witch and encourages a more authentic representation of the male witch that is akin to those who practice witchcraft. There are non-toxic examples of masculinity that challenge the potential for stereotyping, hence there is a need for a better representation of what it means to be a witch within popular culture.

Gillette’s historically successful “razor and blade” business model (RBM) has been a promising benchmark for multiple businesses across diverse industries worldwide in the past several decades. The extant literature deals with very few nuances of this business model notwithstanding the fact that there are several variants of this business model being put to practical use by firms in diverse industries in grossly metaphorically equivalent situations.

This study adopts the 2 × 2 truth table framework from the domains of mathematical logic and combinatorics in fleshing out all possible (four logical possibilities) variants of the razor and blade business model for further analysis. This application presents four mutually exclusive yet collectively exhaustive possibilities on any chosen dimension. Two major dimensions (viz., provision of subsidy and intra- or extra-firm involvement in the making of razors or blades or both) form part of the discussion in this paper. In addition, this study synthesizes and streamlines entrepreneurial wisdom from multiple intra-industry and inter-industry benchmarks in terms of real-time firms explicitly or implicitly adopting several variants of the RBM that suit their unique context and idiosyncratic trajectory of evolution in situations that are grossly reflective of the metaphorically equivalent scenario of razor and recurrent blades. Inductive method of research is carried out with real-time cases from diverse industries with a pivotally common pattern of razor and blade model in some form or the other.

Several new variants of the razor and blade model (much beyond what the extant literature explicitly projects) have been discovered from the multiple metaphorically equivalent cases of RBM across industries. All of these expand the portfolio of options that relevant entrepreneurial firms can explore and exploit the best possible option chosen from them, given their unique context and idiosyncratic trajectory of growth.

This study has enriched the literature by presenting and analyzing a more inclusive or perhaps comprehensive palette of explicit choices in the form of several variants of the RBM for the relevant entrepreneurial firms to choose from. Future research can undertake the task of comparing these variants of RBM with those of upcoming servitization business models such as guaranteed availability, subscription and performance-based contracting and exploring the prospects of diverse combinations.

Smart entrepreneurial firms identify and adopt inspiring benchmarks (like razor and blade model whenever appropriate) duly tweaked and blended into a gestalt benchmark for optimal profits and attractive market shares. They target diverse market segments for tied-goods with different variants or combinations of the relevant benchmarks in the form of variegated customer value propositions (CVPs) that have unique and enticing appeal to the respective market segments.

Value-sensitive customers on the rise globally choose the option that best suits them from among multiple alternatives offered by competing firms in the market. As long as the ratio of utility to price of such an offer is among the highest, even a no-frills CVP may be most appealing to one market segment while a plush CVP may be tempting to yet another market segment simultaneously. While professional business firms embrace resource leverage practices consciously, amateur customers do so subconsciously. Each party subliminally desires to have the maximum bang-to-buck ratio as the optimal return on investment, given their priorities ceteris paribus.

Prior studies on the RBM have explicitly captured only a few variants of the razor and blade model. This study is perhaps the first of its kind that ferrets out many other variants (more than ten) of the razor and blade model with due simplification and exemplification, justification and demystification.