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The purpose of this paper is to provide a comprehensive historical review of the role of the Federal Reserve in retail payments in the USA.

It reviews the literature on the role of the Federal Reserve and assessments of its involvement.

In addition to its oversight and operational role, the Federal Reserve has conducted R&D and facilitated technology adoption. It has provided effective competition to the private sector without subsidies.

The Federal Reserve has served the public interest and private networks have benefited from the “visible hand” of government.

Migration to electronic payments will likely change its role from an operator to setting standards for safety and security.

The historical review provides context against which the future strategy of the Federal Reserve may be assessed.

After fifteen years of use by U.S. Federal government agencies, purchase cards are still caught in a debate between the drive to improve governmental efficiency and the need to prudently manage and control spending of taxpayer resources. This paper gives decision makers facts by which to evaluate the purchase card experience to date by providing a brief history of legislative actions related to purchase cards, analyzing patterns of purchase card spending by Federal government agencies, estimating the potential size of the purchase card program, and identifying the costs and benefits of shifting low-value transactions to the purchase card. The paper concludes with recommendations for government action.

An ideal method for predicting the fatigue life of spherical thrust elastomeric bearings has not been reported, thus far. This paper aims to present a method for predicting the fatigue life of laminated rubber spherical thrust elastomeric bearings.

First, the mechanical properties of standard rubber samples were tested; the axial stiffness, cocking stiffness, torsional stiffness and fatigue life of several full-size spherical thrust elastomeric bearings were tested. Then, the stiffness results were calculated using the neo-Hookean, Mooney–Rivlin and Yoeh models. Using a modified Mooney–Rivlin constitutive model, this paper proposes an improved method for fatigue life prediction, which considers the laminated characteristics of a spherical thrust elastomeric bearing and loads of multiple multi-axle conditions.

The Mooney–Rivlin model could accurately describe the stiffness characteristics of the spherical thrust elastomeric bearings. A comparative analysis of experimental results shows that the model can effectively predict the life of a spherical thrust elastomeric bearing within its range of use and the prediction error is within 20%.

The fatigue parameters of elastomeric bearings under multiaxial loads were fitted and corrected using experimental data and an accurate and effective multiaxial fatigue-life prediction expression was obtained. Finally, the software was redeveloped to improve the flexibility and efficiency of modeling and calculation.

This paper aims to theoretically and numerically investigate the steady two-dimensional (2D) Hiemenz flow with heat transfer of Reiner-Rivlin fluid over a linearly stretching/shrinking sheet.

The Navier–Stokes equations are transformed into self-similar equations using appropriate similarity transformations and then solved numerically by using shooting technique. A simple but effective mathematical analysis has been used to prove the existence of a solution for stretching case (λ> 0). Moreover, an attempt has been laid to carry the asymptotic solution behavior for large stretching. The obtained asymptotic solutions are compared with direct numerical solutions, and the comparison is quite remarkable.

It is observed that the self-similar equations exhibit dual solutions within the range [λ_c, −1] of shrinking parameter λ, where λ_c is the turning point from where the dual solutions bifurcate. Unique solution is found for all stretching case (λ > 0). It is noticed that the effects of cross-viscous parameter L and shrinking parameter λ on velocity and thermal fields show opposite character in the dual solution branches. Thus, a linear temporal stability analysis is performed to determine the basic feasible solution. The stability analysis is based on the sign of the smallest eigenvalue, where positive or negative sign leading to a stable or unstable solution. The stability analysis reveals that the first solution is stable that describes the main flow. Increase in cross-viscous parameter L resulting in a significant increment in skin friction coefficient, local Nusselt number and dual solutions domain.

This work’s originality is to examine the combined effects of cross-viscous parameter and stretching/shrinking parameter on skin friction coefficient, local Nusselt number, velocity and temperature profiles of Hiemenz flow over a stretching/shrinking sheet. Although many studies on viscous fluid and nanofluid have been investigated in this field, there are still limited discoveries on non-Newtonian fluids. The obtained results can be used as a benchmark for future studies of higher-grade non-Newtonian flows with several physical aspects. All the generated results are claimed to be novel and have not been published elsewhere.

A previously presented finite element shell formulation is extended to the application of large strains. The finite elements are those based on the concept of ‘the degenerated solids’, which are widely used in non‐linear finite element programs. The constitutive equation of hyperelastic incompressible material is adopted and specialized to the Mooney‐Rivlin law. The additional state variable, the hydrostatic pressure, which occurs for incompressible materials, is eliminated on element level using the plane stress condition. Attention is drawn to the efficient calculation of the element matrices by applying a layer concept. The effectiveness of the proposed total Lagrangian formulation is demonstrated in a number of example problems.

Nano‐imprint forming (NIF) is a manufacturing technology capable of achieving high resolution, low‐cost and high‐throughput fabrication of fine nano‐scale structures and patterns. The purpose of this paper is to use modelling technologies to simulate key process steps associated with the formation of patterns with sub‐micrometer dimensions and use the results to define design rules for optimal imprint forming process.

The effect of a number of process and pattern‐related parameters on the quality of the fabricated nano‐structures is studied using non‐linear finite element analysis. The deformation process of the formable material during the mould pressing step is modelled using contact analysis with large deformations and temperature dependent hyperelastic material behaviour. Finite element analysis with contact interfaces between the mould and the formable material is utilised to study the formation of mechanical, thermal and friction stresses in the pattern.

The imprint pressure, temperature and the aspect ratio of grooves which define the pattern have significant effect on the quality of the formed structures. The optimal imprint pressure for the studied PMMA is identified. It is found that the degree of the mould pattern fulfilment as function of the imprint pressure is non‐linear. Critical values for thermal mismatch difference in the CTE between the mould and the substrate causing thermally induced stresses during cooling stage are evaluated. Regions of high stresses in the pattern are also identified.

Design rules for minimising the risk of defects such as cracks and shape imperfections commonly observed in NIF‐fabricated nano‐structures are presented. The modelling approach can be used to provide insights into the optimal imprint process control. This can help to establish further the technology as a viable route for fabrication of nano‐scale structures and patterns.

This work presents a review of the application of hyperelastic models to the analysis of fabrics using finite element analysis (FEA).

In general, a combination of uniaxial tension (compression), biaxial tension, and simple shear is required for the characterization of a hyperelastic material. However, the use of these deformation tests to obtain the mechanical properties of a fabric may be complicated and also expensive. A methodology for characterizing the fabric employing a different experimental test is presented. The methodology consists of a comparison of the results of the fabric characterization with only a tensile test and the combination of shear, biaxial, and tension experimental tests by using FEA.

Numerical results of the fabric behavior contribute to estimate the effects of experimental limitations in the material characterization and to select the best fit material model to modeling fabrics. Finally, a comparison of hyperelastic material models is illustrated through an example of a rigid body in contact with a hyperelastic fabric in 3D.

Hyperelastic models are used to characterize textile materials.

The purpose of this study is to synthesise the available peer-reviewed literature on the impact of time out of cell (TOOC) and time in purposeful activity (TIPA) on adverse mental outcomes amongst people in prison.

The outcomes of interest of this literature review were mental health, suicide, deliberate self-harm (DSH) and violence. Exposures of interest were TOOC, TIPA or a partial or indirect measure of either. In total, 14 studies were included. An abbreviated review methodology was used because of time constraints.

There was consistent evidence of an association between lower TOOC and TIPA and worse mental health and higher suicide risk. Limited evidence suggests a link between TOOC and DSH. No evidence was identified regarding the relationship between TOOC/TIPA and violence.

A lack of longitudinal studies prevents conclusions regarding causality. Significant heterogeneity of mental health outcomes limits the comparability of studies.

These findings highlight the importance of considering the impact of TOOC and TIPA on adverse mental outcomes for prisoners when designing prison regimes, including during urgent adaptation of such regimes in response to Covid-19. They are likely to be of interest to practitioners and policymakers concerned with prison regime design.

This paper is the first to synthesise the existing literature on the impact of TOOC and TIPA on mental health outcomes.

The United States’ population is rapidly aging. As older people require more expensive medical and nursing attention, health-care/nursing costs keep rising, to the extent that they are not sustainable. As a result, the USA is faced with an ethical dilemma. While egalitarian ethical principles and the provisions of the American Nurses Association (ANA) code of ethics require the provision of medical/nursing care to everyone regardless of age, severity of disease and productivity, utilitarians view that as impossible. Assuming that provisions ANA’s codes of ethics are the same as ethical principles, this paper aims to discuss the debate between those two sides in detail.

The paper, viewing the rise of health-care/nursing costs as the cause of the above ethical dilemma, discusses Daniel Callahan’s utilitarian argument that, given the ever-rising health/nursing costs as a percentage of GDP, the USA will be forced to ration health care/nursing on the basis of age. The ethical arguments opposing Callahan’s arguments will also be presented.

While the debate between those two viewpoints is bond to continue, some writers have tried to find a compromise, a solution by assuming that, through efficiency, health/nursing costs can be lowered, making Callahan’s age-based rationing unnecessary.

This paper is original as it, by including nursing costs as an inseparable component of health-care costs, makes the aforementioned debate applicable to nursing care.

The purpose of this paper is to investigate the correlates of suicidal ideation in offenders incarcerated in three Belgian prisons.

A cross-sectional questionnaire design was used. In total, 60 participants were recruited from three Belgian prisons. In addition to a questionnaire regarding demographic, social, institutional, and criminological factors, validated self-report instruments of psychological and psychiatric variables (coping, hopelessness, and depressive symptomatology) were administered. Associations with suicidal ideation were tested using regression analysis.

Coping style, life events, and social support were most strongly associated with suicidal ideation in prisoners. In particular, a passive coping style, feelings of loneliness, and the loss of a significant other contributed most to the presence of suicidal ideation, whereas a close partner relationship constituted a protective factor of suicidal thoughts.

This pilot study used a convenience sampling strategy, prone to sampling bias. Additionally, given the small sample size, results must be interpreted with caution, as they might not be representative of the general population of prisoners in Belgium.

Interventions focussing on improving coping skills and social support and on impeding the availability and accessibility of suicide methods are promising suicide prevention strategies in custodial settings.

To date, no studies have been conducted in Belgium focussing on suicidality in prisoners. Furthermore, the examination of suicidal ideation in prison settings has received relatively scant attention in international research.