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Aims: To describe the development and report the first‐stage validation of a digital version of the digit symbol substitution test (DSST), for assessment of cognitive function in older people with diabetes. Materials and Methods: A multidisciplinary team of experts was convened to conceptualize and build a digital version of the DSST and develop a machine‐learning (ML) algorithm to analyse the inputs. One hundred individuals with type 2 diabetes (aged ≥ 60 years) were invited to participate in a one‐time meeting in which both the digital and the pencil‐and‐paper (P&P) versions of the DSST were administered. Information pertaining to demographics, laboratory measurements, and diabetes indices was collected. The correlation between the digital and P&P versions of the test was determined. Additionally, as part of the validation process, the performance of the digital version in people with and without known risk factors for cognitive impairment was analysed. Results: The ML model yielded an overall accuracy of 89.1%. A strong correlation was found between the P&P and digital versions (r = 0.76, p < 0.001) of the DSST, as well as between the ML model and the manual reading of the digital DSST (r = 0.99, p < 0.001). Conclusions: This study describes the development of and provides first‐stage validation data for a newly developed digital cognitive assessment tool that may be used for screening and surveillance of cognitive function in older people with diabetes. More studies are needed to further validate this tool, especially when self‐administered and in different clinical settings. [ABSTRACT FROM AUTHOR]

Introduction: Non Specific Low Back Pain (NSLBP) is a frequent problem faced by the majority of postmenopausal women at some stage of their lives, resulting in a significant level of disability. Aim: To evaluate the effectiveness of core stabilisation exercises compared to traditional physical treatment in postmenopausal women with NSLBP. Materials and Methods: A prospective longitudinal study was conducted from January 2022 to August 2022, including 50 postmenopausal women aged 45-60 years with NSLBP. They were placed into two groups. Conventional LBP physical therapy methods were administered to group 2. The identical traditional and Core muscle Stabilisation Exercises (CSE) were implemented in the group 1. The Modified Oswestry Disability Index (MODI) was used for the assessment of disability. The Mann-Whitney U test and Friedman Analysis of Variance (ANOVA) were conducted to analyse changes in disability scores across and among groups at the ends of the second, fourth, and sixth weeks of treatment. Results: Of 50 patients initially enrolled in the study, 33 patients were available for the final follow-up. Group 1 consisted of 16 patients, while group 2 had 17 patients. Significant reduction in disability was found across the two groups at the second, fourth, and sixth weeks of treatment (p-value<0.05). In the sixth week of treatment, group 1 had a statistically greater decrease in ODI score (41.16±13.53) than group 2 (30.74±13.28) (p-value =0.003). Conclusion: CSE were found to be more effective than conventional physical therapy in reducing disability associated with NSLBP in postmenopausal women. [ABSTRACT FROM AUTHOR]

Likened to both thermosets and thermoplastics, vitrimers are a unique class of materials that combine remarkable stability, healability, and reprocessability. Herein, this work describes a photopolymerized thiol‐ene‐based vitrimer that undergoes dynamic covalent exchanges through uncatalyzed transamination of enamines derived from cyclic β‐triketones, whereby the low energy barrier for exchange facilitates reprocessing and enables rapid depolymerization. Accordingly, an alkene‐functionalized β‐triketone, 5,5‐dimethyl‐2‐(pent‐4‐enoyl)cyclohexane‐1,3‐dione, is devised which is then reacted with 1,6‐diaminohexane in a stoichiometrically imbalanced fashion (≈1:0.85 primary amine:triketone). The resulting networks exhibit subambient glass transition temperature (Tg = 5.66 °C) by differential scanning calorimetry. Using a Maxwell stress‐relaxation fit, the topology‐freezing temperature (Tv) is calculated to be −32 °C. Small‐amplitude oscillatory shear rheological analysis enables to identify a practical critical temperature above which the vitrimer can be successfully reprocessed (Tv,eff). Via the introduction of excess primary amines, this work can readily degrade the networks into monomeric precursors, which are in turn reacted with diamines to regenerate reprocessable networks. Photopolymerization provides unique spatiotemporal control over the network topology, thereby opening the path for further investigation of vitrimer properties. As such, this work expands the toolbox of chemical upcycling of networks and enables their wider implementation. [ABSTRACT FROM AUTHOR]

This work studies the effect of interlayer adhesion on mechanical performance of fluorinated thermoplastics produced by fused deposition modeling (FDM). Here, we study the anisotropic mechanical response of 3D-printed binary blends of poly (vinylidene fluoride) (PVDF) and poly (methyl methacrylate) (PMMA) with the isotropic mechanical response of these blends fabricated via injection molding. Various PVDF/PMMA filament compositions were produced by twin-screw extrusion and, subsequently, injection-molded or 3D printed into dog-bone shapes. Specimen mechanical and thermal properties were evaluated by mode I tensile testing and differential scanning calorimetry, respectively. Results show that higher PMMA concentration not only improved the tensile strength and decreased ductility but reduced PVDF crystallization. As expected, injection-molded samples revealed better mechanical properties compared to 3D printed specimens. Interestingly, 3D printed blends with lower PMMA content demonstrated better diffusion (adhesion) across interfaces than those with a higher amount of PMMA. The present study provides new findings that may be used to tune mechanical response in 3D printed fluorinated thermoplastics, particularly for energy applications. [ABSTRACT FROM AUTHOR]

To probe reaction kinetics and polymer decomposition, energetic filaments composed of aluminum (Al) and poly(vinylidene fluoride) (PVDF) with varying hexafluoropropylene (HFP) content are tested for processability and combustion characteristics. Rheological and crystallization findings indicate that the Al‐binder interfacial interactions are disrupted by HFP content. Thermal analysis shows that fuel consumption scales with Al particle size due to the diffusion‐driven Al‐fluoropolymer reaction regardless of HFP concentration. Char yield analysis shows that more solid product is retained in samples with smaller particle diameters, which further reflects the diffusive nature of both Al‐PVDF and Al‐P(VDF‐HFP) reactions. Burn rates reveal two competing mechanisms for reaction efficiency: 1) accelerated binder decomposition through Al‐PVDF interactions and 2) more energetic fluorination due to higher fluorine content in the P(VDF‐HFP) binders. Finally, powder X‐ray diffraction (PXRD) patterns show that AlF3 is the primary product from self‐propagating burns. However, in larger Al particle sizes, filaments are unable to burn completely and result in high levels of Al2O3 and Al4C3 formation, which indicates that these binders are not amenable with low surface area, metallic fuels. These findings aim to improve fluorinated feedstock selection for potential binder candidates in energetic additive manufacturing (AM). [ABSTRACT FROM AUTHOR]

Polyhedral oligomeric silsesquioxane (POSS) nanostructured chemicals, when incorporated at low levels in thermoplastics, provide processability enhancement and viscosity reduction without compromising other bulk physical properties. POSS has been relatively unexplored in high performance polymers, and there is incomplete understanding of the mechanisms by which POSS produces flow improvements. In this study, polyethersulfone (PES) was melt‐blended with trisilanolphenyl (TSP)‐POSS and dodecaphenyl (DP)‐POSS; and rheological, dielectric spectroscopy, and scanning electron microscopy evaluations were conducted to identify structure/property/processing relationships. TSP‐POSS yielded greater processability improvements and viscosity reductions than DP‐POSS, suppressed low temperature relaxations to a larger extent, and displayed a greater degree of nanoscale dispersion in the polymer matrix. The findings are evaluated in terms of competing theories of POSS viscosity reduction. [ABSTRACT FROM AUTHOR]