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Review of the use of waste resources in sustainable concrete : aggregate types, recycling procedures, fresh and hardened properties, structural characteristics, and numerical formulation
No full textCivil engineering is strongly associated with the construction of various structures as one of the main human needs. However, construction materials production could damage human and animal health and threaten the environment due to using natural resources. Therefore, using recycling and waste materials derived from old building devastation plays a crucial role in less natural resource consumption and reducing waste materials dumping. For this aim, many studies have been done on using waste and natural materials instead of natural coarse and fine aggregates. This article includes a review of the literature on the production and use of waste resources instead of natural aggregates to produce egocentric concrete in concrete. Due to its larger water absorption and minor density, the waste particles may result in a little drop in the slump and compressive resistance. The author investigated methods for removing mortar that has adhered to aggregates to increase the material quality. Also, it was shown the practicality of using structural components constructed of recycled aggregate concrete in full-scale projects or laboratory tests. Finally, this study could help engineers, agencies, and standards to have a comprehensive view of the using waste and recycled aggregates to produce concrete structures and elements
Parametric study of low-rise buildings using a smart hybrid rocking structural system with vertical dampers
No full textIn the recent past, smart and resilient cities, and their expansion, have become a global concern. It is vital to design a more seismically resistant structure without having to demolish and rebuild the entire building or repair broken connections caused by natural environmental threats, such as major earthquakes. The theoretical model of rocking systems consists of three separate structures and a variety of unique features and auxiliary devices. They are supposed to meet the performance requirements and withstand massive deformations while sustaining controlled sequential failures. There are also principal auxiliary devices that eliminate residual stresses within the ductile elements and restore the structure to its initial position. It is possible to take advantage of all other components to reduce seismic demand on the combined system as well. The primary focus of the current chapter is to analyze the influence of the change in the rocking core's devices that were used to dissipate the seismic energy and to evaluate the post-earthquake behavior and seismic performance of the low-rise structure, comprising gravity frames and a rocking core. Furthermore, the time-history dynamic approach was used to investigate the effects of near-field ground motion characteristics on the suggested structures' responses
Do environmental scores become multinational corporations' strategic "greenwashing" tool for window-dressing carbon reduction? : a cross-cultural analysis
No full textOwing to the urgency of the climate change crisis and the emerging greenwashing issue that companies face, greenwashing in companies' carbon reduction is exceptionally important in the progress of global carbon reduction and the achievement of the Paris Agreement goals. Therefore, this study focused on multinational corporations (MNCs) listed on the 2021 Fortune Global 500 list (2001–2020) and used institutional theory to theoretically discuss and empirically test the relationship between MNCs' environmental scores and carbon emissions/intensity, as well as the moderating effect of national culture. Our results demonstrate that the environmental scores of MNCs positively affect their carbon emissions and intensity, meaning that managers tend to use high scores to hide their poor carbon reduction, showing a typical “talk” more and “act” less (i.e., greenwashing) behavior. Meanwhile, the moderating effects of individualism, masculinity, and uncertainty avoidance were negative. These revealed that the balance of MNCs' “talk” and “act” can be influenced by the domestic national cultural characteristics. Further analysis showed that the Paris Agreement did not prevent MNCs' greenwashing in carbon reduction. Such greenwashing behavior has become even worse in societies with power distance characteristics after the Paris Agreement. To the best of our knowledge, this is the first study to investigate companies' greenwashing in terms of carbon reduction. The goal is to enhance our understanding of why and how greenwashing occurs based on the institutional theory perspective, extend the application of institutional theory, enrich the literature on companies' greenwashing and national culture, and offer insight into interdisciplinary research between national culture and green transition management. Finally, suggestions for policymakers on how to prevent MNCs' greenwashing in carbon reduction, considering national cultural influence, were provided
Effects of metallicity on the instability mass ratio of low-mass contact binary systems
No full textThe orbital stability of contact binary systems has been receiving considerable attention recently. Theoretical studies indicate that merger is likely to occur at very low-mass ratios, but the actual mass ratio at which merger may take place is likely to be variable and dependent on the mass of the primary. We consider the effects of metal content on the orbital stability of contact binary systems by modelling the gyration radius of a rotating and tidally distorted primary component at various values of [Fe/H] in the range −1.25 to +0.5. We determine the instability mass ratio range for contact binary systems with a low-mass primary 0.6 Mʘ ≤ M1 ≤ 1.4 Mʘ at various metallicity levels and show that systems with low metallicity have an instability mass ratio lower than those with higher metal content and therefore are likely to be more stable. We illustrate the effect through light-curve analysis of two otherwise very similar contact binary systems, except for different metallicity. While both would be considered unstable if metallicity was not taken into consideration, only one remains in that category after appropriate adjustments based on metallicity have been made
Examining plurilingual repertoires : a focus on policy, practice, and assessment in the Australian context
No full textThis chapter discusses policy, practice, and assessment research pertaining to plurilingualism in the Australian context, with a focus on mainstream classrooms. In the recent past, Australian language policy was pioneering in its support and promotion of the maintenance and acquisition of languages other than English. However, since the late 1980s, languages and education policy have predominantly been characterised by a relentless move towards monocultural and monolingual conceptualisations of language and literacy in curriculum, pedagogy, and assessment across Australian education systems. Discussion centres on the role of educational policy and practice and the affordances and challenges offered when plurilingualism is placed at the centre of teaching and learning in mainstream Australian classrooms. The chapter considers the linguistic, cognitive, and social benefits that can be derived from recognising and harnessing students' plurilingual repertoires, and the competing tensions of predominantly monolingual, monoglossic educational policies, curricula, and assessment frameworks. The central contention is that assessment practices are failing to keep pace with conceptual and pedagogical progress in the education system and are perpetuating reductive interpretations of language and literacy that continue to limit the effectiveness of current pedagogical change
Distributed leader-following consensus of feedforward nonlinear delayed multiagent systems via general switched compensation control
No full textThis work examines the distributed leader-following consensus problem of feedforward nonlinear delayed multiagent systems involving directed switching topologies. In contrast to the existing studies, we focus on time delays acting on the outputs of feedforward nonlinear systems, and we permit that the partial topology dissatisfy the directed spanning tree condition. In the cases, we present a novel output feedback-based general switched cascade compensation control method that addresses the above-mentioned problem. First, we put forward a distributed switched cascade compensator by introducing multiple equations, and we design the delay-dependent distributed output feedback controller with the compensator. Subsequently, when the control parameters-dependent linear matrix inequality is met and the switching signal of the topologies obeys a general switching law, we prove that the established controller can render that the follower’s state asymptotically tracks the leader’s state by employing an appropriate Lyapunov–Krasovskii functional. The given algorithm allows output delays to be arbitrarily large and increases the switching frequency of the topologies. A numerical simulation is presented to demonstrate the practicability of our proposed strategy
Performativity and affective atmospheres in digitally mediated care labour
No full textThis paper offers an exploration of women’s experiences of engaging in digitally mediated care work. Data for this article is drawn from qualitative interviews conducted with 15 young women in Australia to explore their experiences of securing care work through a digital platform. Importantly, we focus on both online and offline dimensions of securing work, thus contributing to the extant literature which has tended to focus on the online aspects of securing platform work. Through the complementary lenses of performativity and affective atmospheres, we examine the complexities of presenting an idealised self to obtain work opportunities from an online pool of diverse care-seekers, and the bodily performances and attributes required offline to secure actual work. We conclude by reflecting on how online and offline interactions explicate the normative performativity required by young women to successfully access digitally mediated service work
Upregulation of Nrf2 signaling : a key molecular mechanism of Baicalin's neuroprotective action against diabetes-induced cognitive impairment
No full textBackground and aim: Diabetes-associated cognitive impairment (DCI) is a prevalent complication of diabetes. However, there is a lack of viable strategies for preventing and treating DCI. This study aims to explore the efficacy of baicalin (Bai) in attenuating DCI and elucidating the underlying mechanisms.
Experimental procedure: GK rats fed a high-fat and high-glucose diet were utilized to investigate the therapeutic potential of Bai. Cognitive function was assessed using the Morris water maze and novel object recognition tests. To gain insight into the molecular mechanisms underlying Bai’s neuro-protective effects, co-cultured BV2/HT22 cells were established under high-glucose (HG) stimulation. The modes of action of Bai were subsequently confirmed in vivo using the DCI model in db/db mice.
Key results: Bai restored cognitive and spatial memory and attenuated neuron loss, along with reducing expressions of Aβ and phosphorylated Tau protein in diabetic GK rats. At the cellular level, Bai exhibited potent antioxidant and anti-inflammatory effects against HG stimulation. These effects were associated with the upregulation of Nrf2 and supressed Keap1 levels. Consistent with these in vitro findings, similar mechanisms were observed in db/db mice. The significant neuroprotective effects of Bai were abolished when co-administered with ATRA, a Nrf2 blocker, in db/db mice, confirming that KEAP1-Nrf2 signaling pathway was responsible for the observed effect.
Conclusions and implications: Bai demonstrates a great therapeutic potential for attenuating DCI. The antioxidant defense and anti-inflammatory actions of Bai were mediated through the KEAP1-Nrf2 axis. These findings advance our understanding of potential treatment approaches for DCI, a common complication associated with diabetes
Commoning repair : framing a community response to transitioning waste economies
No full textIn this paper we sketch-out community economies of reuse and repair to address questions of look and scale posed by the session abstract titled Scales of Reuse and Repair: Diversity, Degrowth and Transformative Circularity. With a focus on community-led activities in two local government areas, the paper identifies plural economies of material circulation alive in social practices of reuse, repair and share in western Sydney, aligning with national, state and local government agendas to move to a circular economy as integral to the sustainable future of Australian cities. We propose that amongst the first tasks in the transition to a circular economy is creating a ‘repair commons’ that includes the contribution of local civic society. Drawing on two studies exploring cultures of repair and community waste practices in western Sydney—one of the most culturally diverse and rapidly transforming urban areas in the world—we show that transition means a recalibration of the relationship between governments and communities, and a renegotiation of responsibilities for managing household waste. Employing a community economies lens, our vignette of a community of repair commoners is enabled by an ‘identikit’ of a locality transformed by possibilities of making and remaking from the already made. We intend to enact the ‘transformative thinking’ that Miller and Gibson-Graham (2019) call for in making other possibilities visible in the midst of the world we have now. The provocation offered by this session is to consider how our picture of a repair commons generates a different scalar imaginary with potential to contribute to planning and policy environments prioritising a shared civic responsibility for material culture
Character strength-based cognitive-behavioral therapy focusing on adolescent and young adult cancer patients with distress : a randomized control trial of positive psychology
No full textPositive psychological therapy has been found to be effective in psychological health in the broader cancer patient population. However, specific evidence regarding its effectiveness for adolescent and young adult (AYA) cancer patients remains limited. More research is needed to determine the optimal approaches for alleviating distress in this particular group. We evaluated the efficacy of character strength-based cognitive-behavioral therapy (CS-CBT) versus cognitive-behavioral therapy (CBT) for distress in AYA patients with cancer. In a randomized controlled three-arm trial, cancer patients aged 15-39 years were assigned to one of three groups using a random number table to ensure equal group sizes: (1) CS-CBT, which incorporated specific exercises focused on identifying and utilizing character strengths within the CBT framework; (2) CBT; or (3) control group. The primary outcome was improvement in patients’ overall mental health on the Distress Thermometer and the Hospital Anxiety and Depression Scale 3 months after assignment to the groups. Analyses used generalized estimating equations. A total of 162 AYAs were randomly and equally assigned to three groups. Improvements in primary outcomes were significantly greater after CS-CBT than after CBT, and no significant differences were found between the CBT and control group. Among all primary and secondary outcomes, the only non-significant difference found was in quality of life with CS-CBT compared to CBT. AYA cancer patients rated their overall mental health and sense of thriving as more improved after CS-CBT than after CBT. However, quality-of-life indicators supported equal intervention effects in both groups. These findings support the effectiveness of the use of CS-CBT intervention in reducing distress and improving thriving