Scientific Community Research Articles

Combinatorial Effects of 5-Fluorouracil and Menadione on Wnt/β-Catenin Pathway in Human Colorectal Cancer Cells.

The incidence and mortality rates of colorectal cancer (CRC) are alarmingly high, and the scientific community is consistently engaged in developing newer therapeutic options for cancer cure or prevention. The fluoropyrimidine drug, 5-fluorouracil (5FU), remains the first line of treatment against CRC; nevertheless, relapses frequently occur since the cells gain resistance over time through various mechanisms. Studies have highlighted the significance of combinatorial treatment of a Wnt signaling inhibitor and 5FU as a better treatment strategy to overcome 5FU resistance. Small molecules that specifically target and disrupt β-catenin-TCF interaction, a crucial step of the Wnt signaling, are promising in CRC treatment. In this study, we investigated the synergistic cytotoxic activity of menadione with 5FU as the former has previously been shown to downregulate Wnt signaling in CRC cells. Docking and experimental results suggest that the drug combination interfered with key protein-protein interactions in the β-catenin-TCF complex, exerted synergistic anti-cancerous effects in CRC cells, and downregulated the expression of Wnt signaling proteins. Taken together, our data suggest that the simultaneous binding of 5FU and menadione to β-catenin can block Wnt signaling by disrupting β-catenin-TCF interaction and inhibit the proliferation of CRC cells.

Historical Architecture and BIM Modelling: Between Representation of Reality and Conceptual Abstraction

The essay aims to explore the applications of BIM to design regarding historic buildings, which will become mandatory in Italy from 2025 for public works above €1 million. Despite the advantages in coordinated data management and information sharing among the actors involved in contracts, problems related to the geometric representation and semantic definition of the virtual entities that populate the models have been recognized by the scientific community. Critical issues that have emerged from the study of significant experiences can be traced back to the difficulty of adapting tools designed for the projects of new buildings to the characteristics of the cultural heritage. In particular, the complexity of proposing congruent categorisations and parameterisations seems related to only partial correspondence between historical building components, IFC classes and BIM software categories. These limitations often lead to the identification of contingent solutions and expedients, which solve only the problems of geometric representation. In contrast, the ability to adequately share information stored in databases, interoperable through the IFC format, is conveyed by an appropriate semantic description. Formal representation in the BIM environment effectively refers to standardized industrial production, reproducibility of building elements and, more generally, to the goals of globalisation. Thus, the proposed reflections aim to encourage a conscious use of these tools and to outline implementation perspectives useful to bring the digital environment closer to the concrete reality of historical architecture, unique and irreproducible in origin and transformation, often realized through artisanal processes and anchored to specific contexts in multiple aspects.

Functionally Graded Metamaterials: Fabrication Techniques, Modeling, and Applications—A Review

Functionally Graded Metamaterials (FGMMs) constitute an innovative class of materials within the realm of additive manufacturing (AM), attracting substantial attention from material science and research communities. These materials, characterized by unique designs and gradient properties, are not commonly found in nature but are deliberately engineered through the arrangement of subwavelength structures. The distinct attributes of such materials have propelled them into significant prominence across various industries, including automotive, aerospace, medical, electronics, and agriculture. This review paper aims to present a comprehensive overview of a range of techniques applied in the fabrication, design, theoretical models, and simulation methods related to these materials. It delves into the assessment of such material’s performance, specifically focusing on mechanical, thermal, and electromagnetic properties. Moreover, this review addresses advancements, challenges, and potential solutions in the field. Ultimately, it delivers valuable insights to researchers, practitioners, and stakeholders, enhancing their understanding of FGMMs and their significance in the broader context.

Advancing Nuclear Research and Education in Slovenia and EU: From Operating the TRIGA Reactor to Building a New Generation Facility

AbstractThe TRIGA Mark II research reactor at the Jožef Stefan Institute in Slovenia achieved first criticality in 1966. Since then, the reactor has been playing an important role in developing nuclear technology. The reactor has been mainly used for research, education of university students, training of operators of the Krško nuclear power plant (start of operation in 1983) and other nuclear specialists, isotope production and beam applications. The reactor is experiencing a high level of activity today, engaging in a diverse range of experiments and studies across reactor physics, environmental research, radiation hardness testing as well training and education. The future of nuclear technology in Slovenia is focused on new NPPs, while the research community is looking forward to a possible new nuclear reactor. The basic initiatives are at a very preliminary stage: the primary choice is dual-core pool-type reactor, with a zero-power core and a separate MW-size core, cooled and moderated with light water. Such a dual-core configuration is designed to meet the varied requirements of the European Union member states. Another option would be hosting one or more micro-reactors with electrical and/or heating power producing capability that could offer stronger support toward demonstration of prototype small modular reactors in prototype future electrical grids.

Artificial intelligence and adolescents’ socialization: risks of influence

Importance. To date, there is an active introduction of artificial intelligence into all spheres of human activity, leading to significant changes in the factors that influence the socialization of the younger generation. Along with this, smart devices have also begun to act as agents of socialization for modern teenagers, with whom they interact both in educational and extracurricular settings. In this regard, the scientific and pedagogical community is interested in identifying both the positive and negative aspects of AI’s influence on the formation of the social experience of minors. The aim of the study is to examine the features and analyse the risks associated with the artificial intelligence impact on the adolescents’ socialisation.Research Methods. The work is based on a comprehensive review of psychological, pedagogical, legal, sociological, scientific, and technical literature on artificial intelligence the introduction in various fields of human activity, particularly in the education sector. The study is grounded in personal-activity, multi-subject, and environmental perspectives, which allowed for the synthesis and analysis of relevant information, as well as an assessment of the potential risks associated with the artificial intelligence influence on the positive socialization process of school students. Within these frameworks, several research methodologies are employed, including analysis, comparison, generalization, systematization, and structured information organization.Results and Discussion. The main areas of artificial intelligence application in education are: adaptive learning, automated assessment, examination management, personalized learning, customized educational materials creation, consultation and recommendation systems, gaming and virtual reality, extending the range of opportunities for students with special needs, and monitoring student engagement in learning. However, along with the potential benefits of introducing AI technologies into the adolescents’ cognitive development, there are several risks associated with the intelligent devices’ use: a potential decrease in the education quality, challenges with social skills and self-regulation development, value orientation, adaptation, and self-regulatory resources. Additionally, there is a risk of subjectivity loss, the formation of an unrealistic self-image, aggressive behavior, and the development of digital autism and information pseudoliteracy.Conclusion. Based on the analysis, it is revealed that the artificial intelligence influence on modern adolescents can be traced not only in changing the educational process of the school, which is a factor and institution of socialization, but also in the direct interaction between a minor and a smart device. At the same time, this process has both positive and negative aspects, the consideration and correction of which is necessary when introducing artificial intelligence into education and other spheres of human activity and society.

Some Comments on the Nature of Glasses Or a brief history of time and temperature in glass-forming liquids*

Abstract Here we undertake a brief presentation of the early history of the development of our modern understanding of glass-forming liquids that provides a look at how the scientific and technological communities were viewing the state of the art and how the knowledge in the field developed. We discuss aspects of our understanding from how the VFT equation became known to questions about the development of the concept of the “ideal” glass transition. The framework for this history leads us to ask the question whether some of the cautions that the pioneering researchers provided should have been taken more seriously by the community. We discuss in particular: The view presented by Tammann and Hesse (G. Tammann and W. Hesse, “Die Abhängigkeit der Viscosität von der Temperatur bie unterkühlten Flüssigkeiten,” Z. Anorg. Allg. Chem., 156, 245–257 (1926)) cautioning that the apparent singularity of the viscosity at a finite temperature was not physical and the, now famous, VFT equation is accurate for interpolation rather than for extrapolation. The other point is the strong sense by much of the glass community that the so-called Kauzmann (W. Kauzmann, "The nature of the glassy state and the behavior of liquids at low temperatures," Chem. Rev., 43, 219-256 (1948)) paradox is fundamental to glass-formation despite the comment by Kauzmann, himself, that the extrapolation of the entropy to negative values is “operationally meaningless”. We build on these ideas through a presentation of our own data and that of others that addresses the Tammann and Hesse comment through experiments that show there is not a viscosity (or relaxation time) divergence near to the Kauzmann or VFT temperatures and we show that the equilibrium entropy of a polymer that cannot crystallize shows no evidence of an “ideal” glass transition that is often invoked as a means of avoiding the Kauzmann paradox. In addition to providing some sense of the history of time and viscosity we think that the data we present leads to the conclusion that much of our understanding of the problem of glass-formation is based on misleading interpretations of the original works as well as being inconsistent with the newer data that has been published over that past 25 years or so. On an optimistic note, there are newer models that do not rely on the VFT divergence or the Kauzmann paradox to account for glass-formation in supercooled or equilibrium liquids. In addition, the experimental situation clearly leads to the possibility of deeper investigations into the “deep glassy state” through “finessing” the geological time-scale issue of creating equilibrium glasses. Such investigations are ultimately important to understanding behavior of glassy materials, especially polymers, that are used deep in the glassy state, but still close enough to the glass temperature that models able to reliably predict their behavior require better representations of glass-formation to engineer their performance.

Quest for Orthologs in the Era of Biodiversity Genomics.

The era of biodiversity genomics is characterised by large-scale genome sequencing efforts that aim to represent each living taxon with an assembled genome. Generating knowledge from this wealth of data has not kept up with this pace. We here discuss major challenges to integrating these novel genomes into a comprehensive functional and evolutionary network spanning the tree of life. In summary, the expanding datasets create a need for scalable gene annotation methods. To trace gene function across species, new methods must seek to increase the resolution of ortholog analyses, e.g., by extending analyses to the protein domain level and by accounting for alternative splicing. Additionally, the scope of orthology prediction should be pushed beyond well-investigated proteomes. This demands the development of specialised methods for the identification of orthologs to short proteins and non-coding RNAs, and for the functional characterization of novel gene families. Furthermore, protein structures predicted by machine learning are now readily available, but this new information is yet to be integrated with orthology-based analyses. Finally, an increasing focus should be placed on making orthology assignments adhere to the FAIR principles. This fosters green bioinformatics by avoiding redundant computations and helps integrating diverse scientific communities sharing the need for comparative genetics and genomics information. It should also help with communicating orthology-related concepts in a format that is accessible to the public, to counteract existing misinformation about evolution.

A (sub)field guide to quality control in hippocampal subfield segmentation on high-resolution T2-weighted MRI.

Inquiries into properties of brain structure and function have progressed due to developments in magnetic resonance imaging (MRI). To sustain progress in investigating and quantifying neuroanatomical details in vivo, the reliability and validity of brain measurements are paramount. Quality control (QC) is a set of procedures for mitigating errors and ensuring the validity and reliability of brain measurements. Despite its importance, there is little guidance on best QC practices and reporting procedures. The study of hippocampal subfields in vivo is a critical case for QC because of their small size, inter-dependent boundary definitions, and common artifacts in the MRI data used for subfield measurements. We addressed this gap by surveying the broader scientific community studying hippocampal subfields on their views and approaches to QC. We received responses from 37 investigators spanning 10 countries, covering different career stages, and studying both healthy and pathological development and aging. In this sample, 81% of researchers considered QC to be very important or important, and 19% viewed it as fairly important. Despite this, only 46% of researchers reported on their QC processes in prior publications. In many instances, lack of reporting appeared due to ambiguous guidance on relevant details and guidance for reporting, rather than absence of QC. Here, we provide recommendations for correcting errors to maximize reliability and minimize bias. We also summarize threats to segmentation accuracy, review common QC methods, and make recommendations for best practices and reporting in publications. Implementing the recommended QC practices will collectively improve inferences to the larger population, as well as have implications for clinical practice and public health.

Ten simple rules to bridge ecology and palaeoecology by publishing outside palaeoecological journals.

Owing to its specialised methodology, palaeoecology is often regarded as a separate field from ecology, even though it is essential for understanding long-term ecological processes that have shaped the ecosystems that ecologists study and manage. Despite advances in ecological modelling, sample dating, and proxy-based reconstructions facilitating direct comparison of palaeoecological data with neo-ecological data, most of the scientific knowledge derived from palaeoecological studies remains siloed. We surveyed a group of palaeo-researchers with experience in crossing the divide between palaeoecology and neo-ecology, to develop Ten Simple Rules for publishing your palaeoecological research in non-palaeo journals. Our 10 rules are divided into the preparation phase, writing phase, and finalising phase when the article is submitted to the target journal. These rules provide a suite of strategies, including improved networking early in the process, building effective collaborations, transmitting results more efficiently and cross-disciplinary, and integrating concepts and methodologies that appeal to ecologists and a wider readership. Adhering to these Ten Simple Rules can ensure palaeoecologists' findings are more accessible and impactful among ecologists and the wider scientific community. Although this article primarily shows examples of how palaeoecological studies were published in journals for a broader audience, the rules apply to anyone who aims to publish outside specialised journals.

Fruit Wastes and Crop Residues as Nutrient Sources for Bacterial Nanocellulose Production: A Review

Nanocellulose has been developed and used as a bio-based advanced material in modern biotechnology. Lately, bacterial nanocellulose (BNC) emerged as a prominent biopolymer because of its multi-functional application in various industries, such as food, biomedical, cosmetics, and environmental. The emerging concern for large-scale BNC production is the high fermentation costs, low productivity, and expensive culture medium. To minimise this issue, agro-industrial wastes can be used as feedstock. Recently, many studies have investigated the utilization of agro-industrial wastes as potential nutrient sources for BNC production. However, a comprehensive review of BNC production from fruit wastes and crop residues is lacking. To address this gap, the current review focuses on the utilization of fruit wastes and crop residues for BNC production, including its advantages and disadvantages. This study contributes to the scientific community by (a) providing an insight into fruit waste and crop residue utilization for BNC synthesis (b) an overview on its advantages and disadvantages (c) providing recommendations and future perspectives on BNC production from agro-industrial waste utilization. The sustainable concept of BNC production utilizing agro-industrial wastes opens a way for industries to produce BNC on a larger scale.

The Different Concentrations of Applied Exogenous Sugars Widely Influence the Specificity, Significance and Physiological Relevance of Study Outcomings.

Plant growth and development are governed via signal networks that connect inputs from nutrient status, hormone signals, and environmental cues. Substantial researches have indicated a pivotal role of sugars as signalling molecules in plants that integrate external environmental cues and other nutrients with intrinsic developmental programmes regulated via multiple plant hormones. Therefore, plant growth and development are controlled through complication signalling networks. However, in many studies, to obtain more obviously experimental findings, excess concentrations of applied exogenous sugars have aggravated the complexity of this signalling networks. Once researchers underestimate this complexity, a series of contradictory or contrasting findings will be generated. More importantly, in terms of these contradictory findings, more contradictory study outcomings are derived. In this review, we carefully analyze some reports, and find that these reports have confused or neglected that the sugar-antagonism of ethylene signalling is specific or conditional. As a result, many contradictory conclusions are generated, which will in turn misdirect the scientific community.

AVR/I/SSAPDB: a comprehensive & specialised knowledgebase of antimicrobial peptides to combat VRSA, VISA, and VSSA.

The rise of multi-drug resistant (MDR) bacteria, especially strains of Staphylococcus aureus like Vancomycin-resistant S. aureus (VRSA), Vancomycin-intermediate S. aureus (VISA), and Vancomycin-susceptible S. aureus (VSSA), poses a severe threat to global health. This situation underscores the urgent need for novel antimicrobial agents to combat these resistant strains effectively. Here, we are introducing the Anti-Vancomycin-Resistant/Intermediate/Susceptible StaphylococcusaureusPeptide Database (AVR/I/SSAPDB), a manually curated comprehensive and specialised knowledgebase dedicated to antimicrobial peptides (AMPs) that target VRSA, VISA, and VSSA with clinical and non-clinical significance. Our database sources data from PubMed, cataloging 491 experimentally validated AMPs with detailed annotations on peptides, activity, and cross-references to external databases like PubMed, UniProt, PDB, and DrugBank. AVR/I/SSAPDB offers a user-friendly interface with simple to advanced and list-based search capabilities, enabling researchers to explore AMPs against VRSA, VISA, and VSSA. We are hoping that this resource will be helpful to the scientific community in developing targeted peptide-based therapeutics, providing a crucial tool for combating VRSA, VISA, and VSSA, and addressing a major public health concern. AVR/I/SSAPDB is freely accessible via any web-browser at URL: https://bblserver.org.in/avrissa/ .

Characterizing coagulation responses in humans and nonhuman primates following kidney xenotransplantation-A narrative review.

The recent report of the first pig kidney transplant in a living human brings hope to thousands of people with end-stage kidney failure. The scientific community views this early success with caution as kidney xenotransplantation exhibits many challenges and barriers. One of these is coagulation dysregulation. This includes (i) pig von Willebrand Factor (vWF) interaction with human platelets, which can induce abnormal clotting responses, heightening the risk of graft failure, (ii) the inefficiency of pig thrombomodulin in activating human protein C, which emphasizes the species-specific variations that aggravate coagulation challenges, and (iii) the development of thrombotic microangiopathy in the pig grafts and the occurrence of systemic consumptive coagulopathy in the recipients. Indeed, coagulation dysregulation largely results from differences in endothelial cell response and incompatibilities between pig and human coagulation-anticoagulation pathways. These barriers can be resolved by modifications to pig vWF and the expression of human thrombomodulin and endothelial protein C receptors in pig cells, serving as strategic interventions to align the coagulation systems of the two species more closely. These coagulation challenges have clinical implications in how they affect graft survival and patient outcome. Genetic engineering of the organ-source pig and the administration of various drugs have assisted in correcting this coagulation dysregulation. Hence, comprehending and controlling coagulation dysregulation is crucial for progress in xenotransplantation as a viable option for treating patients with terminal kidney disease.

Reasons for retraction of clinical research articles in PubMed indexed medical journals from 2012 to 2022

Background: Misconduct in the publication of research articles is a serious concern for the scientific community. This study was conducted with the objective to assess various reasons for retraction of clinical research articles published in PubMed indexed journals from all over the world since 2012 to 2022. Methods: A search was performed on the PubMed database for retracted research articles using filters for “retracted publication”. A total of 314 eligible research articles were assessed for studying basic details. The study outcome measures were to evaluate the reasons for the retraction and authors’ and journal editors’ responses to retractions. Results: Of the original research articles retracted, 150/242 (61.98%) were clinical trial publications. Of the total 314 retracted research articles, the most retractions were in 2014 (47, 14.96%) and 2013 (40, 12.73%) while the fewest retractions were in 2012 (3, 0.95%) and 2022 (9, 2.86%). The most common reasons for retraction were data errors or data analysis errors (120/314, 38.21%) followed by plagiarism (37/314, 11.8%), duplicate publication (35/314, 11.1%), ethical concerns (23/314, 7.3%) and methodological flaws (22/314, 7%). These concerns were raised mainly by the editor or editor-in-chief (228/314, 72.61%), followed by authors (29/314, 9.23%). Out of 228 editorial concerns on publications, authors of only 91/228 (39.91%) agreed and 17/228 (7.45%) completely disagreed with the editorial decision. Conclusion: Authors need to be more careful about data analysis errors, fabricated or falsified data, and plagiarism while submitting their research papers. On the part of editors, detecting misconduct at the submission and peer review stages will help lower the retraction rate and avoid citation of such articles by other authors.

Research Hotspots and Development Trends of Theme Activities in Kindergartens since 21st Century—Based On Visual Co-word Analysis

In order to accurately and objectively understand the composition and development trend of research hotspots on kindergarten theme activities in the past decade, China National Knowledge Infrastructure (CNKI) was used as the literature search source. The Co-word analysis software Bicomb2.0 and data statistical software SPSS27.0 were used to conduct time-series, research strength, high-frequency key, cluster analysis, and multidimensional scale analysis on 1674 literature on kindergarten theme activities from 2005 to 2023, and to draw knowledge graphs at different time periods. Research has found that the study of kindergarten theme activities generally revolves around five major areas: research on the selection of theme activity content, research on the connotation and characteristics of theme activities, research on the design of theme activities, research on the implementation and value of theme activities, and research on the theory and reform of theme activities. Strengthening the construction of theme activities in kindergartens is an effective breakthrough for achieving high-quality preschool education curriculum. Therefore, future research should focus on the combination of educational theory workers and educational practice workers to form a research community; Exploring diverse perspectives, deep learning and STEAM courses will become new academic growth points for themed activities; Innovative research paradigm, emphasizing the combination of theoretical research and empirical research.

Teacher Use of Generative AI for Read‐Aloud Question Prompts

AbstractThe advent of Generative AI technologies, such as ChatGPT, in November 2022, necessitated immediate and critical attention from the educational research community. The impact of GenAI in education, though not yet clear, has the potential to be transformative. More specifically, the focus of this paper is on how to integrate GenAI into elementary literacy education. We, as teacher educators, aim to showcase how to prompt ChatGPT to generate high‐quality questions during a read‐aloud. We discuss the easy access teachers have to GenAI tools and stress the pivotal role they have in decision‐making. We encourage teachers to explore, learn, and understand how to work with GenAI tools to get the most out of it and thus facilitate their agency, teaching, and learning.

The Role of Media Education in Qualification of Students for Media Work Market (Survey Study)

This research aims to identify the role of media education in qualifying students for the media job market. And investigating the role of media education in developing media talents among media students in universities and government institutes in the Kurdistan Region - Iraq. For its type of descriptive study, the research relied on a sample survey method for the community of graduates of media departments in universities and government institutes. The sample was drawn from the original research community in a non-random, intentional manner. The total number of respondents included (134) media graduates from all governorates of the region. Among the most important findings of the research: The results showed a positive role for media education in qualifying students for the media work market in universities, technical and governmental academic institutes in the Kurdistan Region - Iraq, and a somewhat negative role, related to the lack of availability of media departments with the necessary equipment and applied means for producing media work.

Hu.MAP3.0: Atlas of human protein complexes by integration of > 25,000 proteomic experiments.

Macromolecular protein complexes carry out most functions in the cell including essential functions required for cell survival. Unfortunately, we lack the subunit composition for all human protein complexes. To address this gap we integrated >25,000 mass spectrometry experiments using a machine learning approach to identify > 15,000 human protein complexes. We show our map of protein complexes is highly accurate and more comprehensive than previous maps, placing ∼75% of human proteins into their physical contexts. We globally characterize our complexes using protein co-variation data (ProteomeHD.2) and identify co-varying complexes suggesting common functional associations. Our map also generates testable functional hypotheses for 472 uncharacterized proteins which we support using AlphaFold modeling. Additionally, we use AlphaFold modeling to identify 511 mutually exclusive protein pairs in hu.MAP3.0 complexes suggesting complexes serve different functional roles depending on their subunit composition. We identify expression as the primary way cells and organisms relieve the conflict of mutually exclusive subunits. Finally, we import our complexes to EMBL-EBI's Complex Portal ( https://www.ebi.ac.uk/complexportal/home ) as well as provide complexes through our hu.MAP3.0 web interface ( https://humap3.proteincomplexes.org/ ). We expect our resource to be highly impactful to the broader research community.

Perceptions about dementia clinical trials among underrepresented populations: a nationally representative survey of U.S. dementia caregivers

BackgroundThe research community has historically failed to enroll diverse groups of participants in dementia clinical trials. A unique aspect of dementia care research is the requirement of a study partner, who can attest to the care recipient’s clinical and functional capacity. The aim of this study is to assess racial and ethnic differences and the importance of various trial considerations among dementia caregivers, in their decision to participate in clinical research as study partners.MethodWe embedded a vignette about a hypothetical dementia clinical trial in a nationally representative survey of U.S. dementia caregivers, oversampling non-Hispanic Black and Hispanic caregivers. Dementia caregivers were asked about their willingness to participate in the trial with their care recipient and rated the importance of nine considerations in hypothetical decisions to participate. Caregiver demographic characteristics were analyzed as predictors of trial participation in a base demographic model. In a second reasons model caregiver demographic characteristics and the rated importance of the nine considerations were separately analyzed as predictors; both models used survey-weighted logistic regression.ResultThe sample consisted of 610 dementia caregivers, including 156 non-Hispanic Black and 122 Hispanic caregiver participants. In the base demographic model, hypothetical trial participation was negatively associated with older caregiver age (OR (odds ratio) = 0.72, p = < 0.001). In the reasons model, the rated importance of a social responsibility to help others by participating in research was significantly associated with participation (OR = 1.56, p = 0.049), while the importance of the possibility of the care recipient experiencing serious side effects was negatively associated with participation (OR = 0.51, p = 0.003). In both models there was no significant difference in hypothetical participation between non-Hispanic Black and non-Hispanic White caregivers, or between Hispanic and non-Hispanic White caregivers.ConclusionHispanic and non-Hispanic Black dementia caregivers were not less likely than non-Hispanic White dementia caregivers to participate in a hypothetical dementia clinical trial. Our study suggests that failures to recruit diverse populations in dementia clinical research are not attributable to less willingness among members of underrepresented groups but may instead reflect structural barriers and historic exclusion from trial participation.

Exploring the potential of rigid polyurethane foam waste in structural lightweight concrete

The structural lightweight concrete is gaining significant interest in the research community due to its reduced dead load. The reduction in the self-weight not only lowers the gravity load but can also lower the seismic demands for the structural members and hence can potentially reduce the overall cost. This study examines the feasibility of developing a sustainable structural lightweight concrete by utilizing rigid polyurethane foam waste as coarse aggregates (5–10 mm). The silica fume was incorporated as a cement replacement to enhance the compressive strength of the mix. A total of three composite mix formulations consisting of polyurethane foam, cement-coated polyurethane foam, and pumice (control specimens) as coarse aggregates were tested. The testing was performed for workability, compressive strength, flexural strength, elastic modulus, absorption, permeable voids, chloride-ion penetration, freeze and thaw resistance, and drying shrinkage. The results achieved for elastic modulus, chloride ion penetrability, and drying shrinkage, were meeting the minimum requirements of the standards making this composite suitable for the structural application. The results revealed that uncoated polyurethane based lightweight aggregate concrete resulted in an air-dry density of 1829 kg/m3 with the corresponding compressive strength of 19.5 MPa and flexural strength of 2.78 MPa at 28 days. Besides, the polyurethane-based lightweight concrete also showed lower internal structure damage against freeze and thaw action, along with improved thermal conductivity.