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This measuring system is designed to effectively simulate the mechanical reliability of the operated bone fixators. It can be used to pre-evaluate the mechanical performance of the operated fixator on the patients, including the static mechanical properties and fatigue properties when the patient walks after the operation.

It is mainly composed of a one-dimensional platform, a force sensor, a high measuring precision displacement sensor and a servo motor. Loading (which is used to simulate the loading status of the fixators after the operation) of the system is realized by the rotation of the servo motor. It can be read by a high precision force sensor. The relative displacement of the broken bone is obtained by a high precision laser displacement sensor. Corresponding theoretical analysis is also carried out.

Calibrated results of the system indicate that the output voltage and the measured force of the force sensors possess an excellent linear relationship, and the calculated nonlinear error is just 0.0002%. The maximum relative displacement between the operated broken bone under 700 N axial force is about 1 mm. Fatigue test under 550 N loading for 85,000 cycles also indicates the feasibility of the design.

This device is successfully designed and fabricated to pre-evaluate the mechanical performance of the bone fixators. High precision force sensor and displacement sensor are used to successfully increase the measuring ability of the system. This will offer some help to pertinent researchers.

In this paper, the standard Peridynamic Timoshenko beam model accounting for the shear deformation is chosen to describe the thick beam kinematics. Unfortunately, when applied to very thin beam structures, the standard Peridynamics (PD) encounters the shear locking phenomenon, leading to incorrect solutions.

PD differs from classical continuum mechanics and other nonlocal theories that do not involve spatial derivatives of the displacement field. PD is based on the integral equation instead of differential equations to handle discontinuities and other singularities.

The shear locking can be successfully alleviated using the developed selective integration method. In particular, this technique has been implemented in the standard PD, which allows an accurate result for a wide range of slenderness from very thin to thick (10 < L/t < 10³) structures. It can also accelerate the computational time for particular dynamic problems using fewer neighboring integration particles. Several numerical examples are solved to demonstrate the effectiveness of the proposed method for modeling beam structures.

The paper highlights the severe shear locking phenomenon in the Peridynamic Timoshenko beam available in the literature, especially for very thin structures. A new alternative for the alleviation of shear locking in the Peridynamic Timoshenko beam, using selective integration. Hence the developed Peridynamic Timoshenko beam model is effective for thin and thick structures. A new peridynamic formulation for the low-velocity impact beam models is presented and validated.

1. The paper highlights the severe shear locking phenomenon in the Peridynamic Timoshenko beam proposed in the literature, especially for very thin structures.

2. The developed Peridynamic Timoshenko beam model based on selective integration is effective for thin and thick structures.

3. A new peridynamic formulation for the low-velocity impact beam models is presented and validated.

The paper highlights the severe shear locking phenomenon in the Peridynamic Timoshenko beam proposed in the literature, especially for very thin structures.

The developed Peridynamic Timoshenko beam model based on selective integration is effective for thin and thick structures.

A new peridynamic formulation for the low-velocity impact beam models is presented and validated.

The purpose of this paper is to propose a casting process for the production of double-chamber soft fingers, which avoids the problems of air leakage and fracture caused by multistep casting. This proposed method facilitates the simultaneous casting of the inflation chamber and the jamming chamber.

An integrated molding technology based on the lost wax casting method is proposed for the manufacture of double-chamber soft fingers. The solid wax core is assembled with the mold, and then liquid silicone rubber is injected into it. After cooling and solidification, the mold is stripped off and heated in boiling water, so that the solid wax core melts and precipitates, and the integrated soft finger is obtained.

The performance and fatigue tests of the soft fingers produced by the proposed method have been carried out. The results show that the manufacturing method can significantly improve the fatigue resistance and stability of the soft fingers, while also avoiding the problems such as air leakage and cracking.

The improvement of the previous multistep casting method of soft fingers is proposed, and the integrated molding manufacturing method is proposed to avoid the problems caused by secondary bonding.

This study aimed to develop a method to calculate the mattress indentation for further estimating spinal alignment.

A universal indentation calculation model is derived based on the system theory, and the deformation characteristics of each component are analyzed by the finite element (FE) model of a partial air-spring mattress under the initial air pressure of 0.01–0.025 MPa. Finally, the calculation error of the model is verified.

The results indicate that the indentation calculation model could describe the stain of a mattress given the load and the constitutive model of each element. In addition, the FE model of a partial air-spring mattress can be used for further simulation analysis with an error of 1.47–3.42 mm. Furthermore, the deformation of the series system is mainly contributed by the air spring and the components directly in contact with it, while the top component is mainly deflection deformation. In addition, the error of the calculation model is 2.17–5.59 mm on the condition of 0.01–0.025 MPa, satisfying the engineering application. Finally, the supine spinal alignment is successfully extracted from the mattress indentation.

The limitation of this study is that it needs to verify the practicality of the indentation calculation model for the Bonnier spiral spring mattress. The main feature of the Bonnier spring mattress is that all springs are connected, so the mattress deflection and neighborhood effect are more significant than those of the air-spring mattress. Therefore, the applicability of the model needs to be tested. Moreover, it is worth further research to reduce the deformation error of each component.

As part of the series of studies on the intelligent air-spring mattress, the indentation-based evaluation method of spinal alignment in sleep postures will be studied for hardness and intelligent regulation based on this study.

The results of this research are ultimately used for the intelligent adjustment of air-spring mattresses, which automatically adjusts the hardness according to the user's sleep postures and spinal alignment, thus maintaining optimal spinal biomechanics. The successful application of this result could improve the sleep health of the general public.

Based on the series system theory, an indentation calculation model for mattresses with arbitrary structure is proposed, overcoming the dependence of parameters on materials and their combinations when fitting the Burgers model. Further, the spinal alignment in supine posture is extracted from the indentation, laying a theoretical foundation for further recognition and adjustment of the spinal alignment of the intelligent mattress.

This study aims to comprehensively investigate the mixed-mode fracture behavior and mechanical properties of selective laser sintering (SLS) polyamide 12 (PA12) components, considering different build orientations and layer thicknesses. The primary objectives include the following. Conducting mixed-mode fracture and mechanical analyses on SLS PA12 parts. Investigating the influence of build orientation and layer thickness on the mechanical properties of SLS-printed components. Examining the fracture mechanisms of SLS-produced Arcan fracture and tensile specimens through experimental methods and finite element analyses.

The research used a combination of experimental techniques and numerical analyses. Tensile and Arcan fracture specimens were fabricated using the SLS process with varying build orientations (X, X–Y, Z) and layer thicknesses (0.1 mm, 0.2 mm). Mechanical properties, including tensile strength, modulus of elasticity and critical stress intensity factor, were quantified through experimental testing. Mixed-mode fracture tests were conducted using a specialized fixture, and finite element analyses using the J-integral method were performed to calculate fracture toughness. Scanning electron microscopy (SEM) was used for detailed morphological analysis of fractured surfaces.

The investigation revealed that the highest tensile properties were achieved in samples fabricated horizontally in the X orientation with a layer thickness of 0.1 mm. Additionally, parts manufactured with a layer thickness of 0.2 mm exhibited favorable mixed-mode fracture behavior. The results emphasize the significance of build orientation and layer thickness in influencing mechanical properties and fracture behavior. SEM analysis provided valuable insights into the failure mechanisms of SLS-produced PA12 components.

This study contributes to the field of additive manufacturing by providing a comprehensive analysis of the mixed-mode fracture behavior and mechanical properties of SLS-produced PA12 components. The investigation offers novel insights into the influence of build orientation and layer thickness on the performance of such components. The combination of experimental testing, numerical analyses and SEM morphological observations enhances the understanding of fracture behavior in additive manufacturing processes. The findings contribute to optimizing the design and manufacturing of high-quality PA12 components using SLS technology.

This study aimed at exploring support for older people in protracted displacement in Nigeria, emphasising the available support and the gap in the support provided to them.

Qualitative interviews were used to collect data from ten displaced older people in New-Kuchingoro internally displaced persons (IDP) camp Abuja, Nigeria. The collected data were analysed thematically with NVivo 12.

Results show that older people received material, emotional and psychological supports from their families, neighbours, friends, religious organisations and non-governmental organisations. Several gaps were identified in the support provided to displaced older people. For example, their special nutritional or medical needs were neglected, and their support was primarily material, sporadic and spontaneous, as there is no existing framework guiding the care and support of older people in displacement.

This study provides a foundation for further research on older people in displacement, an area that has received minimal scholarly attention.

The paper recommends that researchers and displaced persons’ care providers should pay more attention to the peculiar support needs of this less visible vulnerable group and adopt the internal displacement policy for the long-term protection of older people in displacement.

Older people in displacement remain less visible as humanitarian aid programmes and research focus more on women and children. This lack of attention may put older people in displacement at more risk as their peculiar needs may not be met. To the best of the authors’ knowledge, this study is the first to examine the gap in support for older people in displacement in Nigeria.

Parent–child relationships formed in early childhood have profound implications for a child’s development and serve as a determinant for bio-social outcomes in adulthood. Positive parenting behaviors play a strong role in this development and are especially impactful during times of crisis because they buffer stressors that may lead to externalizing and internalizing behaviors. Children of forced migrants experience numerous extreme stressors and their parents may struggle with parenting due to their own adjustment and trauma histories. The purpose of this study is to understand how these parents conceptualize their struggles with parenting upon resettlement.

The authors conducted semi-structured interviews with 27 migrant parents from three communities (Afghan, Burmese and Congolese) to understand their parenting experiences. The authors applied thematic text analysis to analyze the data.

The authors identified four interrelated themes on parenting challenges across responses: adjustment to a new culture, acculturation differences, fear for children and balancing multiple responsibilities. The findings demonstrate that parents of different cultural backgrounds share certain experiences when negotiating a new cultural identity after resettlement. Providing educational programs that focus on these concerns may result in better outcomes for both parent and child.

These findings extend and reinforce the existing literature on parenting in a new context. While the parents in this research come from different cultures, they share certain experiences that are important to consider when developing parenting programs, social services and other interventions, such as what may be negotiable and nonnegotiable practices for parents of different cultures.

This study focused on Ivorian track and field athletes who were current or former members of the Ivorian national team to understand athletes’ experiences with migration, diaspora and sport.

Participatory action research (PAR) methodology was used in this research study (Lenette and Nesvaderani, 2021). According to Schinke and Blodgett (2016), PAR is a type of qualitative research used to engage the researcher and researched. The researcher and researched work together to understand the issues of a situation and communicate a plan to work toward resolving those issues (Kemmis et al., 2014). Using PAR helped to engage multiple people in the study, and as more research studies explore forced migration and sport, more scholars are starting to lean on the methodology to create a more diverse perspective and to include marginalized populations in the world of scholarly research (Stone, 2018; Robinson et al., 2019).

Key findings illustrate Ivorian athletes’ ability to forge a bond that transcended tribal and political differences through geographical proximity and sport opportunity, allowing them to (re)connect with their Ivorian diaspora by representing the national team.

This research paper expands on past studies in sport and migration by showcasing the fluid nature of how diaspora constructs an athlete’s national identity once they are forced to leave their homeland.