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Additive manufacturing (AM) offers substantial flexibility in shape, but much less flexibility in materials and functionality – particularly at small size scales. A system for automatically incorporating microscale components would enable the fabrication of objects with more functionality. The purpose of this paper is to consider the potential of self‐assembly to serve as an automated programmable integration method. In particular, it addresses the ability of random self‐assembly processes to successfully assemble objects with high performance despite the possibility of assembly errors.

A self‐assembled thermoelectric system is taken as a sample system. The performance expectations for these systems are then predicted using modified one‐dimensional models that incorporate the effects of random errors. Monte‐Carlo simulation is used to predict the likely performance of self‐assembled thermoelectric systems and evaluate the impact of key process and system design parameters.

While assembly yield can drop quickly with increasing numbers of assembled parts, large functional assemblies can be constructed by arranging components in parallel to provide redundancy. In some cases, the performance losses are minimal. Alternatively, sensing can be incorporated to identify perfect assemblies. For small assemblies, the probability of perfection may be high enough to achieve an acceptable assembly rate. Small assemblies could then be combined into larger functional systems.

The paper identifies two strategies that can guide the development of AM processes that incorporate miniature components to increase the system functionality. The analysis shows that this may be possible despite significant errors in the self‐assembly process because systems may be tolerant of significant assembly errors.

Academia’s overwhelming reliance on non-tenure track, or contingent, faculty is a well-known fact. While the status and working conditions of contingent classroom faculty have been well studied and documented, the corresponding trend in academic libraries has not been explored as deeply. As this paper reviews the limited LIS literature on the subject, the purpose of this paper is to provide administrators and managers with a deeper understanding of the benefits and drawbacks of contingent appointments. It also offers strategies for fostering a workplace culture that recognizes contingent librarians’ contributions and promotes their professional growth.

An overview of scholarly and professional literature on contingent librarianship, this paper is based on published research studies and academic articles; given the prominence of anecdotal and personal writing on the subject, columns and first-person essays from trade publications, as well as library-related blogs and job search sites, are also included.

Contingent librarians have been a steady presence in academic libraries for the last few decades. The trend is continuing. There are specific practices that can be applied to effectively manage contingent librarians.

The paper offers academic library administrators and managers a concise yet comprehensive overview of the issues related to contingent appointments.

The purpose of this study is to obtain the numerical as well as regularity results for the nonlinear elliptic set of equations arising in the study of fluid flow in microchannel induced by the pressure in the presence of interfacial electrokinetic effects.

For the numerical study, the authors implemented traditional FDM approach, and for the regularity results they used the classical energy estimates. The interfacial electrokinetic effects result in an additional source term in classical momentum equation, hence affecting the characteristics of the flow and heat transfer. The sinusoidal temperature variation is assumed on side walls.

The results were obtained for various combinations of physical parameters appearing in the governing equations. This study concludes that in the presence of electric double layer, the average heat transfer rate reduces along with larger values of Reynolds number. It is observed that the heat transfer increases with the increase in amplitude ratio and phase deviation. The flow behavior and heat transfer rate inside the microchannel are also strongly affected by the presence of κ (kappa).

To the best of the authors’ knowledge, the problem of heat transfer through microchannel in combination with sinusoidal temperature variation at boundary with electric double layer effects has not been considered previously. Hence, this paper focuses on the influence of the sinusoidal boundary temperature distributions on both sidewalls of a rectangular microchannel through parallel plates with electrokinetic effects on the pressure-driven laminar flow. In addition, a detailed mathematical analysis is also to be carried out to verify the regularity of this model with the proposed boundary conditions. The study used the classical energy method to get the regularity results.

The purpose of this study is to analyze the heat transfer and flow enhancement of an Al₂O₃-water nanofluid filling an inclined channel whose lower wall is embedded with periodically placed discrete hydrophobic heat sources. Formation of a thin depletion layer of low viscosity over each hydrophobic heated patch leads to the velocity slip and temperature jump condition at the interface of the hydrophobic patch.

The mixed convection of the nanofluid is analysed based on the two-phase non-homogeneous model. The governing equations are solved numerically through a control volume approach. A periodic boundary condition is adopted along the longitudinal direction of the modulated channel. A velocity slip and temperature jump condition are imposed along with the hydrophobic heated stripes. The paper has validated the present non-homogeneous model with existing experimental and numerical results for particular cases. The impact of temperature jump condition and slip velocity on the flow and thermal field of the nanofluid in mixed convection is analysed for a wide range of governing parameters, namely, Reynolds number (50 ≤ Re ≤ 150), Grashof number ( 103≤Gr≤5×104), nanoparticle bulk volume fraction ( 0.01≤φb≤0.05), nanoparticle diameter ( 30≤dp≤60) and the angle of inclination ( −60°≤σ≤60°).

The presence of the thin depletion layer above the heated stripes reduces the heat transfer and augments the volume flow rate. Consideration of the nanofluid as a coolant enhances the rate of heat transfer, as well as the entropy generation and friction factor compared to the clear fluid. However, the rate of increment in heat transfer suppresses by a significant margin of the loss due to enhanced entropy generation and friction factor. Heat transfer performance of the channel diminishes as the channel inclination angle with the horizontal is increased. The paper has also compared the non-homogeneous model with the corresponding homogeneous model. In the non-homogeneous formulation, the nanoparticle distribution is directly affected by the slip conditions by virtue of the no-normal flux of nanoparticles on the slip planes. For this, the slip stripes augment the impact of nanoparticle volume fraction compared to the no-slip case.

This paper finds that the periodically arranged hydrophobic heat sources on the lower wall of the channel create a significant augmentation in the volume flow rate, which may be crucial to augment the transport process in mini- or micro-channels. This type of configuration has not been addressed in the existing literature.

During disturbances and unprecedented events, firms are required to be resilient to confront crises, recover from losses, and even capitalize on new opportunities. The aim of this paper is twofold: (1) to examine how different types of capabilities (routine, dynamic or ad hoc) steer an entrepreneurial firm into ecological, engineering and evolutionary resilience and (2) to identify strategic activities that are deployed by firms with different capabilities to achieve resilience.

Data were gathered using structured qualitative interviews with 26 entrepreneurial resilient firms that managed to survive a multitude of coinciding crises.

The findings show that each type of capability enhances the ability to achieve a specific resilience outcome: ad hoc capability for partial engineering resilience, routine capability for ecological resilience and dynamic capability for evolutionary resilience. Furthermore, ad hoc capabilities are shown to be favored when firms' losses are severe. In contrast, routine and dynamic capabilities are preferred when losses are mild. The most significant capability deployment activities related to building resilience are corporate strategic changes, global export strategy, cost reduction, stakeholder support, positive mindset, fund raising, network building, product development, efficiency improvement and restructuring. These activities are segregated based on capability and resilience types.

Practitioners are encouraged to cast off limiting assumptions and beliefs that firms are conditioned to fail when faced with unprecedented crises. This study provides an integrative portfolio of capabilities and activities as a toolbox that can be used by different entrepreneurs and policy makers to achieve resilience and better performance.

The paper undertakes a first of its kind empirical examination of the association between capabilities and resilience. The context is unique as it involves a multitude of coinciding crises including Covid-19 pandemic, city explosion, economic collapse, political instability and a severe banking crisis.

This study aims to assess the relationship between sleep habits and obesity in children.

This is an observational cross-sectional case–control study conducted on 100 children aged 6–12 years, selected randomly from the OPC of the Pediatric Hospital, Ain-Shams University. The subjects were subdivided into two groups: the control group of 50 and the target group of children who are classed overweight or obese. Subjects were excluded where the obesity could be explained owing to an endocrinal and/or any identified disease, those who have a medical or psychiatric illness, and those whose parents refused to give consent. All patients had a full history taken, and each child’s parent fulfilled one questionnaire on sleep behaviors.

This study found that 72% with bedtime resistance compared to only 14% among the control subjects, 68% of children experienced a delay with sleep onset compared to 14% among controls, 68% experienced sleep duration abnormalities compared to 12% in the control group, 60% of children stated they needed their parents while going to sleep, compared to 12% among controls, 64% of cases suffered from walking during the night compared to 12% among controls, 64% of cases had a Parasomnia compared to 12% among controls, 66% of cases snoring loudly compared to 12% among controls, and 66% suffering from Apnea, compared to 6% in the control group, and 50% of cases had daytime sleepiness compared to 14% among controls.

It is hoped that this research will be remedied through the adoption of a child-centered approach inspired by the rights to health and play, and the general principles of the Convention on the Rights of the Child (CRC).

The results showed a strong association between excessive weight and increased risk of sleep problems, which were broadly diffused in the population childhood.

This current study has given us a base for the overwhelming fact that these children are directly affected by obesity. A chronic medical condition has enormous implications on health and can lead to many associated disease processes.

A low‐cost, open source, self‐replicating rapid prototyper (RepRap) has been developed, which greatly expands the potential user base of rapid prototypers. The operating cost of the RepRap can be further reduced using waste polymers as feedstock. Centralized recycling of polymers is often uneconomic and energy intensive due to transportation embodied energy. The purpose of this paper is to provide a proof of concept for high‐value recycling of waste polymers at distributed creation sites.

Previous designs of waste plastic extruders (also known as RecycleBots) were evaluated using a weighted evaluation matrix. An updated design was completed and the description and analysis of the design is presented including component summary, testing procedures, a basic life cycle analysis and extrusion results. The filament was tested for consistency of density and diameter while quantifying electricity consumption.

Filament was successfully extruded at an average rate of 90 mm/min and used to print parts. The filament averaged 2.805 mm diameter with 87 per cent of samples between 2.540 mm and 3.081 mm. The average mass was 0.564 g/100 mm length. Energy use was 0.06 kWh/m.

The success of the RecycleBot further reduces RepRap operating costs, which enables distributed in‐home, value added, plastic recycling. This has implications for municipal waste management programs, as in‐home recycling could reduce cost and greenhouse gas emissions associated with waste collection and transportation, as well as the environmental impact of manufacturing custom plastic parts.

This paper reports on the first technical evaluation of a feedstock filament for the RepRap from waste plastic material made in a distributed recycling device.

A finite element method is applied to evaluate the performance of microchannel heat exchangers that are used in electronic packaging. The present approach is validated against the CFD data available in the literature. A comparison of the predicted results with other available results obtained from different concepts shows that the present method is able to predict the surface temperature, the fluid temperature and thus the total thermal resistance of the microchannel heat sink satisfactorily. The present methodology has an added advantage in that non‐uniform surface heat flux distribution over the package base can also be analysed easily. The method used in the present analysis is an alternative to massive CFD calculations.

The purpose of this paper is to advance our understanding of the challenges of health information literacy (IL) education in disadvantaged and disengaged at-risk populations; and from the perspective of professionals out with information professions occupying everyday support roles.

A qualitative in-depth case study. The participants were a team of UK Family Nurses providing outreach support to young expectant mothers from areas of multiple deprivations, and the mothers themselves. The data collection methods were observation, survey, interviews and focus groups.

Information needs of mothers are multiple, and not always recognised as information problems, or revealed. Several felt overwhelmed, and actively avoided health information. There is low awareness and/or use of state sources of online health information. Family nurses provide an important information intermediary role, but are unfamiliar with IL concepts and models; consequently, there is limited evidence of client transitions to independent information seeking, or underpinning pedagogical practices to achieve such goals.

Further research is required into appropriate pedagogical approaches to IL education adaptable to semi-structured everyday situations. Recognition of information need requires particular attention, including methods of elicitation and specification in the problematic context.

In an era of digital transitions and public service reforms, the authors raise important questions regarding the true reach of public health policy.

The paper holistically examines nurse–client information behaviours, and extends the discussion of low IL in nurses beyond issues of evidence-based practice to issues of developing healthcare self-efficacy in at-risk clients.

This paper aims to discuss the concept of “literacy” within the new literacy, new literacies and library and information science (LIS) discourses. It proposes widening the prevailing LIS conceptualization of adolescent literacy, which focuses largely on information literacy in academic settings, to a broader, information practice-based, sociocultural framing that encompasses the full range of adolescents’ everyday life contexts.

The author presents a literature review and personal reflection on a series of adolescent information activities to show the value of framing the LIS discourse on adolescent literacy within a broader sociocultural perspective.

Based on the discussion, the author proposes a framework for future investigations of adolescents’ literacy practices that views adolescent literacy as fundamentally social and communicative; multiformat; multicontextual; multigenerational; and culturally situated.

A broader sociocultural approach to the LIS information literacy discourse can lead to deeper understanding of the co-constructed and collaborative nature of adolescents’ new literacies practices. It can also enable stronger recognition of the impact of power and privilege on adolescent literacy practices. Finally, this essay shows the value of reflecting on adolescent information activities for challenging narrow views of literacy and highlights the social embeddedness of new literacies activities in adolescents’ everyday lives.