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The Great Gatsby meets Alain Badiou : rethinking fidelity in film adaptation
(AOSIS Books, 2023) Vooght, Ursula
The subject of this book is a consideration of the usefulness of the concept of fidelity put forward by the philosopher Alain Badiou in the discussion of film adaptation. Fidelity or faithfulness is primarily a consideration that emerges in relation to so-called canonical texts in adaptation: Fitzgerald's The Great Gatsby occupies a position of global recognisability and, within the United States, cultural mythology that has triggered strong reactions to the four Hollywood adaptations. The various adaptations allow for the differing approaches to the adaptation of this novel to be meaningfully explored. The film adaptations' paratextual elements will be discussed in order to show how these acted as limiting lenses. The strategies of the films for handling elements of Fitzgerald's prose and themes will be compared across the adaptations. This will culminate in an assertion of the worth of a larger application of a Badiouian fidelity within the field.
Use of secondary gold tailings as fine aggregate in concrete
(Springer Nature Switzerland, 2025) Adeyeye, Rhoda A.; Ikotun, Jacob O.; Otieno, Mike
This research investigates the utilization of secondary gold mine tailings (SGT) in concrete production to address waste management concerns. This approach offers an environmentally friendly substitute for conventional sand, exploring various SGT proportions (ranging from 0% to 100%) as replacements for fine aggregate in concrete. The investigation assessed the fresh, mechanical, and durability properties of concrete made with SGT. The incorporation of SGT diminishes concrete workability while replacement levels of up to 75% exhibit higher fresh concrete density than reference concrete. The findings show that replacing up to 25% enhanced compressive strength, while up to 50% replacement improved splitting tensile strength compared to the reference concrete. Nevertheless, all concrete specimens achieved satisfactory strengths. Furthermore, the durability findings show the concrete specimens were less vulnerable to oxygen, water, and chloride attacks, signifying good-quality concrete. The study proposes substituting SGT for crusher sand to address environmental concerns, lower production costs, and conserve natural resources.
Analyzing the influence of manufactured sand and fly ash on concrete strength through experimental and machine learning methods
(Springer Science and Business Media LLC, 2025-2) Sathvik, S.; Oyebisi, Solomon; Kumar, Rakesh; Shakor, Pshtiwan; Adejonwo, Olutosin; Tantri, Adithya; Suma, V.
River sand supplies are decreasing due to overexploitation and illicit sand mining. One ton of Portland cement production (the main binder in concrete) emits about one ton of carbon dioxide into the atmosphere. Thus, this study replaced conventional cement and river sand (R sand) with recycled waste materials (fly ash and manufactured sand (M sand)). The concrete mix proportions were designed using M40 grade, and the Ordinary Portland cement (OPC) and R sand were replaced with 0-85 wt% of fly ash and 0-100 wt% of M sand. The concrete samples were tested for compressive strength after 3-90 days of curing. Furthermore, machine learning (ML) techniques were engaged to predict the compressive strength of the concrete samples using Extreme Gradient Boosting (XGBoost), Long Short-Term Memory (LSTM), Support Vector Machine (SVM), and Gaussian Process Regression (GPR). Besides, the concrete samples containing fly ash, M sand, and R sand were characterized for microstructures and elemental compositions using SEM-EDS. The results revealed improved concrete compressive strength by incorporating fly ash and M sand. After 28 days of curing, OPC and R sand were partially replaced with 25 and 50 wt% of fly ash and M sand attained the designed strength of M 40 grade concrete. XGBoost model yielded the most accurate performance metrics for forecasting the compressive strength in training and testing phases with R<sup>2</sup> values equal to 0.9999 and 0.9964, respectively, compared to LSTM, SVM, and GPR. Thus, the XGBoost approach can be a viable technique for forecasting the strength of concrete incorporating fly ash and M sand. SEM-EDS analyses revealed compact formations with high calcium and silicon counts. Thus, the XGBoost approach can be a viable technique for forecasting the strength of concrete incorporating fly ash and M sand.
Impact of Bambara groundnut protein modification on complexation behaviour with gum arabic for improved stability and functionality in food applications
(2025) Ojesanmi, Abiola Adenike; Amonsou, Eric Oscar
Protein-polysaccharides complexation has attracted considerable research interest over the past several decades, particularly regarding its role in the encapsulation of bioactive compounds, emulsion stabilization, meat mimetics, and fat replacers. However, complexes usually form within a narrow pH range characterized by weak interactions owing to a tightly packed structure and limited molecular flexibility of the native proteins. Consequently, this restricts the number of oppositely charged groups on globular proteins that can interact with polysaccharides and limits the applications of complexes in certain foods, particularly in acidic beverages. Enhancing the interactions between globular proteins and polysaccharides to achieve stable complex formation requires modifications to the protein structure, composition, and functional properties. Hence, the purpose of this study was to evaluate the influence of various protein modification methods on their physicochemical and structural properties, as well as how these structural changes affect their ability to form complexes with polysaccharides. To achieve this aim, pH-induced fractionation and ionic concentration were utilized as a protocol for extracting and structurally modifying Bambara protein prior to complexation with gum arabic. Additionally, limited trypsin hydrolysis and atmospheric cold plasma were done to modify the protein, and their impact on the stability and properties of complexes was investigated. Finally, encapsulation of riboflavin in a model beverage using Bambara protein hydrolysates (DH 5)- gum arabic soluble complex as a delivery system was determined. Response surface methodology was employed to optimise the pH-induced fractionation of Bambara protein. Thirteen experimental trials were conducted under varying extraction conditions of pH (2.0 to 9.0) and NaCl concentrations (0.0 to 0.6 M), which were considered as independent variables within a central composite design. Complexation behaviour was evaluated through turbidimetric analyses, while structural and conformational changes in fractionated proteins were examined to elucidate their interaction with gum-arabic. Bambara protein fraction obtained at pH 2.95, 0.28 M NaCl produced the most pronounced shift in pHopt (3.4) with spherical microparticles complex and 70% coacervate yield. The modification of protein-gum arabic complexation profile was corroborated by increased content of β-sheet, enriched legumin subunits, and basic amino acids of the protein fraction. Trypsin hydrolysis was done at a controlled degree of 2, 5, and 7.5 prior to complexation with gum arabic focusing on the critical pH structures formations. The hydrolysates were characterized using SEC-HPLC, zeta potential, surface hydrophobicity, and intrinsic fluorescence. Electrostatic interactions between the biopolymers were monitored through turbidimetry analysis. The stability property of the complexes was investigated using differential scanning calorimetry and rheometry. Among the hydrolysates, DH 5 produced the most stable soluble complexes over a broader pH range (7.0 - 4.3), compared to DH 2, DH 7.5, and the unhydrolyzed isolate showed enhanced binding strength and structural stability. This was evidenced by its rheological fingerprints, with DH 5 showing a more pronounced plateau value of Gʹ, indicating a stronger molecular interaction and binding strength between the hydrolysate and gum arabic. This suggests a higher degree of internal structure and makes the complex more stable. Additionally, DH 5 showed a shift in thermal transition temperature, increased negative charge, and surface hydrophobicity. Bambara protein was subjected to atmospheric cold plasma treatment (2, 5 and 10 min) prior to complexation with gum arabic. The impact of the exposure time on composition, structural changes of protein and complex behaviour was analysed. The optimum complexation, pHopt of cold plasma treated Bambara protein-gum arabic complexes significantly shifted to acidic pH following the treatment in an exposure time-dependent manner. The structural changes coincide with the observed shift from α-helix to β-sheet structure, indicating opening of the structure of protein. Crosslinking effects of cold plasma corroborated the breaking of the cross linking disulfide bonds and oxidative modification of proteins, respectively by the chemically reactive species. The variation in the protein composition was associated with a significant rise in positively charged amino acids throughout the cold plasma treatment compared to the untreated protein. The slight red shift in fluorescence intensity data of the plasma protein suggests partial unfolding of the protein structure, correlating with increased hydrophobicity and negative surface charge. The difference between the Gʹ and Gʺ values of the insoluble complex for the untreated proteins increased from < 1 log to ~ 1 log after 10 min exposure time indicating the formation of a stable network structure. The complexes formed at optimal pH (pHopt) of 3.2 and 3.0 could be useful in acidic beverages and may serve as fat replacers in low fat food products. Hence, cold plasma treatment for 5 min could be recommended for a more stable structure. The complexes formed at optimal pH (pHopt) of 3.2 and 3.0 could be useful in acidic beverages and may serve as fat replacers in low-fat food products. Hence, cold plasma treatment for 5 min could be recommended for a more stable structure. Three methods of protein modifications were employed in this study, pH fractionation in the presence of salt, limited enzymatic hydrolysis and emerging atmospheric cold plasma technology. Due to the observed structural changes following each method of modification, a choice of modification strategy depends on the intended objective. The pH fractionation with salt may be adequate for protein sources where high yield is required to produce mild acidic food products. Limited enzymatic hydrolysis and polysaccharides could be appropriate for food products with more stable and better network structure in a wider pH range while atmospheric cold plasma being a non-thermal treatment may be appropriate for heat sensitive food products and where crosslinking of the protein is required. The results of this study are uniquely differentiated by the key variables associated with each modification method, namely: exposure time in cold plasma treatment, enzyme selection in limited hydrolysis, and the range of pH and salt concentrations applied during the extraction fractionation process. This variability highlights the complexity of the research topic and suggests that further investigation is needed to fully understand the relationships between these variables. Additionally, there is a need to determine different results that could be produced when the variables are extended and their applications in other food products.
Extraction and assessing the reinforcing properties of collagen derived from fish on the mechanical properties of polymeric composite : a case of epoxy resin and polyurethane
(2025) Naidoo, Deneshree; Mokhothu, Thabang Hendrica; Onwubu, Stanley C.; Mdluli, Phumlane Selby
Epoxy resin and polyurethane are among the commonly and widely used polymeric materials. However, the high brittleness of cured epoxy polymers promotes crack propagation and limits their impact resistance. Polyurethane (PU), on the other hand, while prized for its flexibility and biocompatibility, is mainly made from petrochemicals, which are now facing environmental concerns. In addition, natural biobased PU foams reportedly have a relatively low mechanical strength. To overcome this, reinforcing epoxy and PU with toughening agents such as collagen is proposed in the literature to enhance its mechanical properties. The fish scale has tremendous unexploited potential for adding these values to waste. Particularly, the fish scale consists of a high amount of collagen, a valuable biomaterial that has found many applications in many fields, including biomedical and pharmaceutical industries. Hence, fish scale-derived collagen has emerged as a promising natural filler, offering eco-friendly, cost-effective, high-performance reinforcement for polymeric composites. The study aims to extract fish scale-derived collagen (FSC) and assess its reinforcing properties as a filler on polymeric composite with special emphasis on epoxy and polyurethane. A quantitative approach following an experimental research design was adopted in this study. The research design comprises three phases. In the first phase, collagen and milled fish scale powder were extracted from fish scale bio-waste using acid hydrolysis and ball-milling techniques, respectively. The extracted collagen was optimised by varying the extraction time, solvent concentration, solvent volume, and tris-glycine buffer. In the second phase, the extracted collagen (FSC) and milled fish scales powder (FS) were characterised with techniques such as X-ray diffraction, Fourier Transform Infrared spectroscopy, Scanning Electron Microscopy, and High-Transmission Electron Microscopy. Additionally, amino acid analysis was conducted to quantify and identify the type and amount of collagen extracted. In the third phase, epoxy (5, 10, 15, 20, and 25 wt.%) and polyurethane (0.5 and 1 wt.%), as well as laminates containing 2.5, 5, and 10 wt.%, were produced following ASTM standards. Mechanical properties, including tensile strength, elongation at break, tear resistance, and flexural strength, were evaluated according to ASTM standards for testing polymeric materials. The thermal stability of the composites was analysed using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). One-way analysis of variance (ANOVA) was performed to assess differences in reinforcing properties (α = .05). The validity of the study was verified using ASTM standards, while reliability was ensured through the processes of repeatability and reproducibility. Paper 1 investigates the incorporation of milled fish scales (MFS) into ether-based polyurethane foam (PUF), revealing enhancements in mechanical properties such as tensile strength, elongation at break, and tear resistance, especially under heat-aging conditions. Paper 1 established that 0.5 wt.% FS improved tensile strength by 18.8% and tear resistance by 22% at elevated temperatures. Additionally, the composites demonstrated reduced density and enhanced flame-retardant properties, underscoring the material's suitability for lightweight and thermally resilient applications. Paper 2 evaluates fish scale collagen (FSC) as a filler, highlighting its amino acid composition and superior mechanical performance. Paper 2 established that the addition of 2.5 wt.% FSC increased tensile strength by 12.66% during heat aging, while 5 wt.% FSC enhanced elongation by 6.65% at standard temperatures. Comparative analysis with traditional fillers, such as calcium carbonate, revealed that FSC could serve as a sustainable substitute without compromising mechanical properties. However, excessive FSC content negatively impacted material flexibility and strength, indicating an optimal concentration of 2.5 wt.%. Paper 3 investigates the reinforcement of epoxy resin composites with fish scale-derived collagen (FSC) to enhance their mechanical and thermal properties. Results indicated significant improvements in tensile strength, Young's modulus, and thermal stability at lower FSC concentrations (5 and 10 wt.%), attributed to effective stress transfer and good interfacial bonding. Overall, this research highlights the potential of natural materials to enhance mechanical properties while addressing sustainability concerns. The findings contribute to the development of eco-friendly and cost-effective materials for various applications, from construction to consumer products.