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This study aims to predict the compression behavior of ultra-high molecular weight polyethylene (UHMWPE) at various temperatures (25, 40, and 55[degrees]C) and strain rates (~[10.sup.-4]/s and ~[10.sup.-2]/s) using a single set of three-network (TN) viscoplastic model parameters. The TN model is made up of three parallel networks: networks A and B use nonlinear springs and dashpots to control the responses of the crystalline phase and confined amorphous phases, respectively, while network C captures the macromolecular amorphous networks using a single nonlinear spring. A single set of TN model parameters captures the yield and post-yield hardening responses of the stress-strain curves at experimental temperatures and strain rates. When these TN model calibrated parameters are used as material property in a commercial finite element tool to simulate UHMWPE compression, the predicted and simulated results match well, showing the model's fidelity. Additionally, the model predicts experiments conducted at 40 and 70[degrees]C with loading rates of ~[10.sup.-3]/s and ~[10.sup.-2]/s, respectively. The study also correlates the deformations of UHMWPE's crystalline structure and macromolecular amorphous networks with its global stress versus strain response by extracting stresses from individual networks of the TN model at different strain rates and temperatures. Highlights * UHMWPE's mechanical behavior predicted by a single set of TN model parameters * TN model predicts mechanical response at various strain rates and temperatures. * TN model explains microstructural crystalline and amorphous phase deformations. KEYWORDS compression properties, numerical simulations, three-network (TN) viscoplastic model, UHMWPE, 1 | INTRODUCTION Ultra-high molecular weight polyethylene (UHMWPE) is one such polymer, which demonstrates an encouraging potential as an impact, chemical, and wear-resistant material. (1) UHMWPE has found diverse applications, [...]

Simple Summary: The cancer journey is often characterized by significant physical and mental health challenges for people with cancer during and after treatment; LGBTQ2S+-identifying people with cancer may face additional issues surrounding their identity and discrimination in health care settings. However, there is limited research that explores the unique experiences of LGBTQ2S+ people with cancer. This study investigates the resilience of LGBTQ2S+-identifying people with cancer to understand how they experienced and coped with cancer. Most participants' cancer journeys were characterized by a 'Second Coming-Out' phenomenon, where LGBTQ2S+ people with cancer use coping strategies, similar to those used when coming out, to produce resilience throughout their cancer journey. Identifying this phenomenon is critical to providing comprehensive care for LGBTQ2S+ people with cancer that draws on their unique strengths. We propose the LGBTQ2S+ Cancer Care Model where the individual is centered and the influences of personal support, professional support, and queer representation are integrated in an accessible and clinically relevant way. People with cancer may suffer negative psychosocial outcomes due to the challenges of cancer. LGBTQ2S+ people routinely experience negative psychosocial outcomes in health care settings, but have showcased resilience in the face of discrimination; however, this has never been studied in a cancer context. Thus, this study aims to assess coping and resilience in LGBTQ2S+-identifying people diagnosed with cancer using a strengths-based approach. A qualitative exploratory design was used. Ten self-identified LGBTQ2S+ people who have completed their cancer treatment were recruited. Participants completed clinical, health, and demographic questionnaires and, subsequently, semi-structured qualitative interviews. Conceptualizations of coping and resilience in the semi-structured interviews were analyzed using interpretative phenomenological analysis (IPA). Participants were members of various gender identities and sexual orientations. In addition to identifying needed LGBTQ2S+-specific resources, four narratives emerged: support networks, regaining control in life, conflicting identities, and traditional coping methods. Most participants' cancer journeys were characterized by a 'Second Coming-Out' phenomenon, where LGBTQ2S+ people with cancer use coping strategies, similar to those used when coming out, to produce resilience throughout their cancer journey. This work provides exploratory insight into LGBTQ2S+ people with cancer, but more research is required with a larger sample. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the compression characteristics of the 3D-printed polylactic acid (PLA) samples at temperatures below the glass transition temperature (Tg) with varying strain rates and develop a thermo-mechanical viscoplastic constitutive model to predict the finite strain compression response using a single set of material parameters. Also, the micro-mechanical damage processes are linked to the global stress–strain response at varied strain rates and temperatures through scanning electron microscopy (SEM). Design/methodology/approach: Tg of PLA was determined using a dynamic mechanical analyzer. Compression experiments were conducted at strain rates of 2 × 10–3/s and 2 × 10–2/s at 25°C, 40°C and 50°C. The failure mechanisms were examined using SEM. A finite strain thermo-mechanical viscoplastic constitutive model was developed to analyze the deformations at the considered strain rates and temperatures. Findings: Tg of PLA was determined as 55°C. While the yield and post-yield stresses drop with increasing temperature, their trend reverses with an increased strain rate. SEM imaging indicated plasticizing effects at higher temperatures, while filament fragmentation and twisting at higher strain rates were identified as the dominant failure mechanisms. Using a non-linear regression analysis to predict the experimental data, an overall R2 value of 0.98 was achieved between experimental and model prediction, implying the robustness of the model's calibration. Originality/value: In this study, a viscoplastic constitutive model was developed that considers the combined effect of temperature and strain rate for FDM-printed PLA experiencing extensive compression. Using appropriate temperature-dependent modulus and flow rate properties, a single set of model parameters predicted the rise in the gap between yield stress and degree of softening as strain rates and temperatures increased. [ABSTRACT FROM AUTHOR]

This study aims to predict the compression behavior of ultra‐high molecular weight polyethylene (UHMWPE) at various temperatures (25, 40, and 55°C) and strain rates (~10−4/s and ~10−2/s) using a single set of three‐network (TN) viscoplastic model parameters. The TN model is made up of three parallel networks: networks A and B use nonlinear springs and dashpots to control the responses of the crystalline phase and confined amorphous phases, respectively, while network C captures the macromolecular amorphous networks using a single nonlinear spring. A single set of TN model parameters captures the yield and post‐yield hardening responses of the stress–strain curves at experimental temperatures and strain rates. When these TN model calibrated parameters are used as material property in a commercial finite element tool to simulate UHMWPE compression, the predicted and simulated results match well, showing the model's fidelity. Additionally, the model predicts experiments conducted at 40 and 70°C with loading rates of ~10−3/s and ~10−2/s, respectively. The study also correlates the deformations of UHMWPE's crystalline structure and macromolecular amorphous networks with its global stress versus strain response by extracting stresses from individual networks of the TN model at different strain rates and temperatures. Highlights: UHMWPE's mechanical behavior predicted by a single set of TN model parametersTN model predicts mechanical response at various strain rates and temperatures.TN model explains microstructural crystalline and amorphous phase deformations. [ABSTRACT FROM AUTHOR]

Short or nanofillers‐reinforced composites increase the thermo‐mechanical characteristics of additive manufacturing (AM) base materials. Effective outputs were regulated via parametric optimisation and custom production. One of the most used AM method, Vat photopolymerization (VPP), creates complex and geometrically precise photopolymer parts. This study prepares photopolymer composite (PPC) samples with 2.0, 4.0, 6.0, and 8.0 volume percentages of short glass fiber (SGF) using an inter‐stage stirring method in DLP‐based VPP process. An adequate curing time and formable layer thickness were evaluated for the printability performance of SGF‐photopolymer composite. The 4.0% PPC‐sample showed a 20% higher compressive yield strength than pure photopolymer and other volume fractions. The consequences of increased strength values were assessed by the effect of stirring method and the fractography analysis of PPC specimen. The investigation additionally encompassed numerical simulations that employed an innovative technique for constructing and simulating three‐dimensional representative volume elements (RVEs). The RVEs were designed to replicate the experimental outcomes by randomly situating and orienting fillers within the matrix. The study employs the calibrated Three Network (TN) viscoplastic constitutive material model as the matrix property, and the simulation results demonstrate a margin of error of 5%–10% when compared to the experimental findings. Highlights: Layer‐wise availability of SGFs through inter‐stage stirring methodThe exposure time and layer thickness were determined by Jacob's working curveConcept of RVE is used to combine individual SGF layers into a single layerSEM showed that increasing SGF layer resists cracking better than neat matrixExperimental data and numerical simulations are in good agreement [ABSTRACT FROM AUTHOR]

Highlights This study aims to improve the compressive strength of epoxy at operating temperatures below the glass transition temperature by introducing micron‐sized spherical and milled glass fillers at varying volume fractions. Test specimens were prepared by mixing spherical and milled fillers up to 20% and 15% volume fractions. The room temperature (27°C) results showed that 15% and 10% volume fractions of spherical and milled filler‐reinforced epoxy composites, respectively, exhibited the highest stress‐bearing ability among their respective filler volume fractions and hence were further tested at 45°C and 60°C. 15% spherical and 10% milled fillers enhanced epoxy's yield strength from 103 MPa to 111 MPa and 123 MPa at 27°C and from 67 MPa to 73 MPa and 80 MPa at 60°C. Scanning electron microscopic imaging revealed matrix cracking and filler breakage as the primary failure mechanisms at ambient temperature, while matrix softening at 60°C caused filler‐matrix debonding to dominate. The Three‐Network viscoplastic model was used as matrix property in ABAQUS to simulate the representative volume elements reinforced with milled and spherical fillers at mentioned temperatures. The modulus, yield, and strain softening stresses for both filler‐reinforced epoxy composites are well predicted by the simulations. Simulations revealed that milled fibers endure higher compressive stress than spherical particles at the given temperatures, although matrix stress remains almost the same. Milled fiber epoxy composites exhibit higher yield strength than spherical ones. 10% milled fiber endures the highest strength among all the fillers used. Matrix and filler breakages are witnessed at ambient temperature. Filler‐matrix debonding dominates at elevated temperature. Three‐Network model captures well the milled and spherical epoxy composite's experimental data. [ABSTRACT FROM AUTHOR]

Background: Having been diagnosed with and treated for cancer can have negative psychosocial repercussions that may differ across the lifespan. Mind-body therapies (MBTs), such as tai-chi/qigong (TCQ) or mindfulness-based cancer recovery (MBCR), have shown promise in decreasing negative psychosocial outcomes in cancer survivors, but few studies have explored potential differences in MBT use and effectiveness across age groups., Methods: A descriptive phenomenological qualitative design was used. Participants included young (18-39), middle (40-64), and older (65+) adult cancer survivors who were diagnosed with any type of cancer and had participated in Mindfulness-Based Cancer Recovery (MBCR) or Tai Chi/Qigong (TCQ) MBTs. Semi-structured qualitative interviews explored participants' experiences in MBTs and these were analyzed using descriptive phenomenological analysis., Results: Among the interviews (n = 18), young (n = 6), middle-aged (n = 8), and older (n = 4) adults participated. 5 themes emerged: influences in joining the program, unique lifestyles, positive class experiences, use of media, and program impacts. Though all age groups benefitted from MBT participation, variations between age groups with respect to the benefits received and motivations for joining the program were observed., Discussion: MBTs had beneficial physical and mental health effects on survivors of all age groups. These benefits were particularly connected to the ongoing life stresses common to each age cohort, such as relief from work and family roles for young adults or support during retirement transition for older adults. Hence, access to MBT programs may be beneficial as part of the survivorship plan for patients and the recruitment strategies or content can be adapted by MBT providers to better target and support age-specific groups. More research is required with a larger sample., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.