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The introduction of Massive Open Online Courses (MOOCs) as a vehicle for education delivery presents opportunities and challenges. In the context of the Wicking Dementia Research and Education Centre (Wicking Centre), the driver to develop a MOOC was the promise of addressing the international deficit in evidence-based dementia education, as well as the lack of research into international perspectives on dementia. The Wicking Centre's activity integrates research and education, framed by the concept of "quality of life across the trajectory of dementia." With dementia emerging as the public health issue of the 21st century, lack of dementia education at multiple levels, professional and non-professional, is of increasing concern. The disruptive character of MOOCs, with associated risks and uncertainties, warranted the application of a research-oriented project management approach to development. This included investing resources in gathering and analysing data to underpin each phase of decision-making. We used a design-based research approach incorporating the concept of "life-cycle of an e-learning design" (Phillips et al. 2012). Data collection and analysis focused on three dynamically interacting components: 1) expertise in dementia knowledge and dementia education; 2) a cohort-centric approach to design and delivery, and 3) models and designs for MOOCs currently promoted, discussed and reported in the higher education discipline. Laurillard's Conversational Framework, relating types of learning, teaching-learning activities and the digital technologies that support them (2012), informed the selection of digital technology elements for massive-scale engagement of our identified cohort. The paper describes the initial design process and the outcomes of the limited release pilot that informed the first full offering of the MOOC.

The article focuses on decisions to exercise and hold company stock at the maturity of a broad‐based employee stock options plan. It investigates why some participants choose an uncertain and risky future reward when an immediate and certain increase in wealth could be secured at exercise. It draws on and expands the "mixed gambles" perspective in behavioral agency theory, utilizing a combination of stock price data and employee survey data from British companies with tax‐approved stock option plans. It is found that the decision to take a gamble is influenced (negatively) by the extent of stock price lows (relative to prices at exercise) in the year prior to exercise, and by the risk preferences of the option holder. The findings contribute to further development of the "mixed gambles" perspective as an explanation of stock option behavior, showing that individual characteristics as well as some stock price movements affect behavior. [ABSTRACT FROM AUTHOR]

Prior studies examining the nonlinear material properties of 6000 series aluminum alloys have predominantly concentrated on analyzing the stress–strain characteristics of these materials under monotonic tensile loading. Limited research has been conducted on their behavior under cyclic loading conditions. To address these gaps, a series of monotonic tensile and variable increasing amplitude cyclic loading tests was conducted on coupons made from 6082-T6, 6063-T6, and 6060-T5 aluminum alloys. The experimental results revealed that as strain amplitude increased the material showed isotropic strain hardening. This combined with the adequate hysteretic energy dissipation capacity demonstrates their potential advantage to be used as in structural components in earthquake prone regions. The experimental results are used to calibrate the material parameters of the uniaxial Giuffrè–Menegotto–Pinto constitutive model to be able to predict the nonlinear stress–strain behavior under monotonic and cyclic loading. Furthermore, using fiber element modeling in OpenSees software, employing a modified Giuffrè–Menegotto–Pinto model, the flexural buckling performance of 6082-T6 aluminum alloy columns is analyzed. The results are compared with existing experimental and finite element data, demonstrating the accuracy of the model in predicting the flexural buckling behavior. [ABSTRACT FROM AUTHOR]

Background: While mid-life hypertension represents a risk factor for the development of Alzheimer's disease (AD), the risk after the age of 65 is less certain. Establishing relationships between late life hypertension and the pathological changes of AD could be crucial in understanding the relevance of blood pressure as a risk factor for this disorder. Objective: We investigated associations between self-reported late-life hypertension, cognitive status and AD pathology at death. The impact of antihypertensive medication was also examined. Methods: Using the Cornell Medical Index questionnaire, we ascertained whether participants had ever reported hypertension. We also noted use of antihypertensive medication. The donated brains of 108 individuals were assessed for AD pathology using consensus guidelines. Statistical analysis aimed to elucidate relationships between hypertension and AD pathology. Results: We found no associations between self-reported hypertension and cognitive impairment at death. However, those with hypertension were significantly more likely to exhibit lower levels of AD pathology as measured by Thal phase, Braak stage, CERAD score, and NIA-AA criteria—even after controlling for sex, level of education and presence of APOEɛ4 allele(s). No significant associations could be found when examining use of antihypertensive medications. Conclusions: Our findings suggest that late-life hypertension is associated with less severe AD pathology. We postulate that AD pathology may be promoted by reduced cerebral blood flow. [ABSTRACT FROM AUTHOR]

This article explores how the immunoreactivity of phosphorylated TDP-43 (pTDP-43) in fixed post-mortem brain tissue can be affected by factors such as long-term storage and prolonged formalin fixation. The study reveals that extended fixation and long-term storage can weaken the immunoreactivity of pTDP-43, but it remains detectable for diagnostic purposes. These findings have implications for the use of brain tissue stored in brain banks for scientific research. The study also found that other proteins, such as amyloid-β and phosphorylated α-synuclein, are not affected by extended fixation or long-term storage, suggesting that existing tissue samples in brain banks can still be used for research, even if they have been stored for many years. [Extracted from the article]

Polymeric heart valves offer the potential to overcome the limited durability of tissue based bioprosthetic valves and the need for anticoagulant therapy of mechanical valve replacement options. However, developing a single‐phase material with requisite biological properties and target mechanical properties remains a challenge. In this study, a composite heart valve material was developed where an electrospun mesh provides tunable mechanical properties and a hydrogel coating confers an antifouling surface for thromboresistance. Key biological responses were evaluated in comparison to glutaraldehyde‐fixed pericardium. Platelet and bacterial attachment were reduced by 38% and 98%, respectively, as compared to pericardium that demonstrated the antifouling nature of the hydrogel coating. There was also a notable reduction (59%) in the calcification of the composite material as compared to pericardium. A custom 3D‐printed hydrogel coating setup was developed to make valve composites for device‐level hemodynamic testing. Regurgitation fraction (9.6 ± 1.8%) and effective orifice area (1.52 ± 0.34 cm2) met ISO 5840‐2:2021 requirements. Additionally, the mean pressure gradient was comparable to current clinical bioprosthetic heart valves demonstrating preliminary efficacy. Although the hemodynamic properties are promising, it is anticipated that the random microarchitecture will result in suboptimal strain fields and peak stresses that may accelerate leaflet fatigue and degeneration. Previous computational work has demonstrated that bioinspired fiber microarchitectures can improve strain homogeneity of valve materials toward improving durability. To this end, we developed advanced electrospinning methodologies to achieve polyurethane fiber microarchitectures that mimic or exceed the physiological ranges of alignment, tortuosity, and curvilinearity present in the native valve. Control of fiber alignment from a random fiber orientation at a normalized orientation index (NOI) 14.2 ± 6.9% to highly aligned fibers at a NOI of 85.1 ± 1.4%. was achieved through increasing mandrel rotational velocity. Fiber tortuosity and curvilinearity in the range of native valve features were introduced through a post‐spinning annealing process and fiber collection on a conical mandrel geometry, respectively. Overall, these studies demonstrate the potential of hydrogel‐polyurethane fiber composite as a heart valve material. Future studies will utilize the developed advanced electrospinning methodologies in combination with model‐directed fabrication toward optimizing durability as a function of fiber microarchitecture. [ABSTRACT FROM AUTHOR]