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Multi-status Bayesian network for analyzing collapse risk of excavation construction
No full textIn response to the need for effective collapse risk analysis in engineering projects, a decision support approach is presented. It is rooted in multi-status Bayesian network (MSBN) and fuzzy set theory, encompassing MSBN construction, risk analysis, and management. This research addresses the causative correlation between influential factors and excavation collapse, considering the inherent uncertainty and fuzziness of the project. To enhance the reliability of evaluation results, an expert confidence index, integrating judgment ability, subjective reliability, and risk preference, is introduced. The approach is applied to an excavation case study, demonstrating its viability and capacity. Furthermore, it offers actionable insights for decision-makers to proactively mitigate accident probabilities. Notably, sensitivity analysis identifies critical risk factors. This research contributes to the field of engineering project risk assessment and management. It serves as a foundation for future research and development, guiding the way for improved strategies and decision support systems
Molecular characterisation of interactions between β-lactoglobulin and hexanal – An off flavour compound
No full textUsing molecular docking and multispectral analytical techniques, the present work investigates the binding characteristics between hexanal and β-lactoglobulin at near neutral pH and ambient temperature. Fluorescence quenching demonstrates that binding between β-lactoglobulin and hexanal is of low to medium strength, having a KA ranging from 9.6 × 102 to 4.0 × 104 M−1, with UV–vis and MALDI-TOF analysis suggesting that interactions are non-covalent in nature. Analysis of secondary structure using both FTIR and CD, shows that the complexation of the ligand with the protein induces an increase in β-sheet structure and a corresponding decrease in α-helical components. The method of continuous variation reveals a 1:1.5 (2:3) binding ratio under the present experimental conditions, suggesting that each β-lactoglobulin dimer may bind 3 hexanal molecules. Molecular docking simulations were consistent with these findings, showing three potential binding locations with distinct binding energies for the dimer. One binding site is located within the hydrophobic calyx of each monomer, while the third site is located at the interface between the two monomers. Knowledge achieved presently may advance our understanding of the fate of flavour compounds in dairy based beverage formulations
Proactive defense mechanism: Enhancing IoT security through diversity-based moving target defense and cyber deception
No full textThe Internet of Things (IoT) has become increasingly prevalent in various aspects of our lives, enabling billions of devices to connect and communicate seamlessly. However, the intricate nature of IoT connections and device vulnerabilities exposes the devices to security threats. To address the security challenges, we propose a proactive defense framework that leverages a model-based approach for security analysis and facilitates the defense strategies. Our proposed approach incorporates proactive defense mechanisms that combine Moving Target Defense techniques with cyber deception. The proposed approach involves the use of a decoy nodes as a deception technique and operating system based diversity as a moving target defense strategy to change the attack surface area of IoT networks. Additionally, we introduce a technique known as Important Measure-based Operating System Diversity to reduce defense cost. The effectiveness of the defense mechanisms was evaluated by using a graphical security model in a Software Defined Networking-based IoT network. Simulation results demonstrate the effectiveness of our approach in mitigating the impact of attacks while maintaining high performance levels in IoT networks
Optimization of secondary air operation parameters of waste incineration boiler based on response surface methodology
No full textTo reduce the NOx emission concentration of waste incineration boilers and improve the thermal efficiency of incinerators, the combustion process of a 600 t/d incineration boiler was numerically investigated. First, the influences of the secondary air injection angle, velocity and temperature on the NOx concentration at the waste incineration boiler outlet and the thermal efficiency of the incinerator were analyzed through a single factor simulation test. Then, coupling optimization of key operating parameters, including the secondary air injection angle, velocity and temperature, was conducted via the response surface design method to obtain the specific functional relationships between outlet NOx concentration, incinerator thermal efficiency, front wall secondary air injection angle, rear wall secondary air velocity and secondary air temperature, as well as the optimal operating parameters for the boiler. The results showed that when the secondary air injection angle of the front wall ranges from 68 degrees similar to 80 degrees and the secondary air injection angle of the back wall is 67 degrees, the minimum NOx concentration is 142.23 mg/m(3), and the maximum thermal efficiency of the incinerator reaches 85.51 %. When the secondary air velocity at the front wall is 42 m/s and the secondary air velocity at the back wall ranges from 42 similar to 66 m/s, the NOx concentration at the outlet is the lowest at 140.05 mg/m(3), and the thermal efficiency of the incinerator is the highest at 85.63 %. When the secondary air temperature ranges from 297.16 similar to 309.16 K, the NOx concentration at the outlet is the lowest at 155.45 mg/m(3), and the thermal efficiency of the incinerator is the highest at 84.64 %. The secondary air injection angle, velocity and temperature impose significant effects on the NOx concentration at the outlet and thermal efficiency of the incinerator. The optimal parameters, as determined in the multifactor simulation test, include a 77 degrees secondary air injection angle of the front wall, 69 m/s secondary air velocity at the back wall, and 297.15 K secondary air temperature. Under these conditions, the NOx concentration at the outlet is 134.98 mg/m(3), and the thermal efficiency of the incinerator reaches 86.11 %. This study has important guiding significance for reducing pollution and improving the efficiency of waste incineration boilers
Design of alkyl-substituted aminothiazoles to optimise corrosion inhibition for galvanised steel: A combined experimental and molecular modelling approach
No full textThis work proposes a combined experimental and molecular modelling approach to clarify the complex substitution effect of aminothiazole as corrosion inhibitor for galvanised steel in saline aqueous environments. Electrochemical results have shown that introducing alkyl residues ameliorates inhibition efficiency to varied degrees. Umbrella sampling simulations supplemented by a newly developed GFN-force-field-based molecular approach reveal that the particular adsorption state renders a hydrophobic environment at the outer surface, where increased alkyl size leads to greater hydrophobicity for corrosion inhibition. Such an effect becomes less prominent with increasing concentration, attributed to the enhanced intermolecular interaction destabilising the adsorption process
Calorie restriction partially attenuates sickness behavior induced by viral mimetic poly I:C
No full textCalorie restriction (CR) has been shown to extend the mean and maximum lifespan in both preclinical and clinical settings. We have previously demonstrated that CR attenuates lipopolysaccharide (LPS)-induced fever and sickness behavior. CR also leads to reductions in pro-inflammatory and increases in anti-inflammatory profiles. LPS is a bacterial mimetic; however, few studies have explored this phenomenon utilizing a viral mimetic, such as polyinosinic:polycytidylic acid (poly I:C). Dose-dependently, poly I:C induced an increase in core body temperature (Tb), with the largest dose (5000 µg/kg) resulting in a 1.62 °C ( ± 0.23 °C) Tb increase at 7 h post-injection in ad libitum mice and was associated with reduced home-cage locomotor activity. We then investigated the effect of 50% CR for 28 days to attenuate fever and sickness behavior induced by a poly I:C (5000 µg/kg) viral immune challenge. CR resulted in the partial attenuation of fever and sickness behavior measures post-poly I:C. The freely fed, control mice demonstrated a 2.02 °C ( ± 0.22 °C) increase in Tb at 7 h post-injection compared to the CR poly I:C group which demonstrated an increase in Tb of 0.94 °C ( ± 0.27 °C). Locomotor patterns post-injection were different, CR mice displayed a reduction in activity during the light phase, and the control group displayed a reduction during the dark phase. CR moderately attenuated the neuroinflammatory response with a reduction in microglial density in the ventromedial nucleus of the hypothalamus. The fever and sickness behavior attenuation seen after CR may be driven by similar anti-inflammatory processes as after LPS; however, further investigation is required
Prevention of post-pandemic crises: A green sustainable and reliable healthcare supply chain network design for emergency medical products
No full textThe COVID-19 pandemic happened exactly when no one expected it and many people died due to the lack of medical equipment. Although pulse oximeters and thermometers were only one of the virus detection equipment, the lack of that equipment could lead to people not knowing about the disease and then the death of those people. Given that these medical devices are very vital in the era of a pandemic, and much less in the later, it is required to provide the best conditions for their use in a closed-loop healthcare supply chain network in post-pandemic. In this paper, a scenario-based two-stage stochastic programming three-objective model for designing a green closed-loop supply chain network is presented. Cost minimization, reliability maximization, and critical response maximization are the objectives of the proposed model. The third objective function is considered for the critical response based on the choice of transportation method. The greenhouse gas emissions for all supply chain elements are considered uncertain and controlled in several possible scenarios. By using an accelerated Benders decomposition algorithm, the mathematical model was solved in different dimensions and the result was analyzed and evaluated in different scenarios. The results demonstrate that the acceleration of Benders bonds reduces the convergence speed of the algorithm by 41%. Our study provides managerial insights into sustainability and reliability, enhancing healthcare supply chain resilience during and after pandemics
Recombinase polymerase amplification-lateral flow assay (RPA-LFA) as a rapid and sensitive test for Escherichia coli O157:H7 detection in food and beverage: A comparative study
No full textEarly and rapid detection of Escherichia coli O157:H7 is required to prevent food and water-borne outbreaks. Several diagnostic methods have been developed in recent decades; it is imperative to find the most sensitive and specific detection method to identify E. coli O157:H7 at the point-of-care (POC) settings. Recombinase polymerase amplification-lateral flow assay (RPA-LFA) has emerged with significant potential of POC application. Therefore, this study aimed to compare RPA-LFA with polymerase chain reaction (PCR), real-time PCR (qPCR), and loop-mediated amplification (LAMP) for use in the diagnosis of E. coli O157:H7. A total of 10 different food and beverages were collected, spiked, and tested, with all four detection methods combined with a lab-dependent (commercial kit) and field-deployable nitrocellulose paper-based DNA extraction method. A comparison of all four techniques based on important parameters such as Affordability, Sensitivity, Specificity, User-friendly, Rapid, Equipment-free, and Deliverability (ASSURED) was also conducted. In addition, the quantitative signal amplification by RPA-LFA was achieved through integration with a benchtop lateral flow strip reader. No significant difference was observed in terms of specificity (100% specific) among the detection techniques regardless of the DNA extraction method. In terms of sensitivity, for the commercial DNA extraction kit, the sensitivity of RPA-LFA was significantly higher compared to the other 3 techniques when applied to food and beverage samples (p < 0.05). The RPA-LFA was found the most sensitive method while LAMP was the least sensitive in detecting E. coli O157:H7 from solid matrices. For the field-deployable DNA extraction method, the sensitivity was also found to be significantly higher for RPA than qPCR, PCR, and LAMP (p < 0.05), irrespective of matrices type. The overall sensitivity of RPA-LFA was higher for beverages than foods. In summary, the inhouse developed nitrocellulose strips can be used to extract DNA from E. coli O157:H7 in under 1 min which can be amplified using RPA at 39 C-degrees for 15 min. Moreover, Sanger sequencing confirmed the specificity of the RPA technique for target amplification. The RPA-LFA, combined with an in-house developed field-deployable DNA extraction method showed potential as a POC detection tool to identify contamination in less than 25 min
Strength design of porous materials using B-spline based level set method
No full textThe inverse homogenization method can tailor some mechanical and physical effective properties by laying out materials in a periodic representative volume element. However, studies on strength design are yet to be developed because of the difficulties in numerically retrieving its value. Unlike traditional asymptotic homogenization, the fast Fourier transform-based homogenization method based on the augmented Lagrangian approach uses a Green operator in the frequency domain to replace time-consuming finite element analysis and inherently meet the periodic boundary conditions. Thus, it is developed in this work to retrieve material strength in terms of the von Mises yield criterion. The zero-level contour of a linear combination of cubic B-spline basis functions with repeated knots is used to represent the microstructure profile in the design of material strength. The effective strength or its squared difference with a prescribed target is minimized within the framework of the reaction diffusion-based B-spline level set method. The filtered, non-consistent discrete Green operator is adopted to avoid slow convergence of porous material. Examples of porous material demonstrate that the proposed method guarantees surface smoothness, optimization flexibility, and structural periodicity in strength design
Unpacking the ‘anti-diet movement’: domination and strategies of resistance in the broad anti-diet community
No full textThis paper explores how those who adopt an ‘anti-diet’ stance use strategies to challenge weight-loss dieting norms. We used a qualitative survey to examine how a heterogenous collective of feminists, fat activists and health professionals (and those on the margins of these groups) define the source(s) of power underlying diet culture and discuss the strategies they use to challenge it. One hundred and eighteen people (Mage = 36.67, SD = 10.50) took part. Most were female (n = 112), heterosexual (69%), and residing in Australia (59%). A small proportion (13%) had a culturally and linguistically diverse (CALD) background. Thirty-seven per cent were health professionals, and over half identified as non-diet activists (52%). We generated three themes in our thematic analysis: ‘Describing diet culture: Unpacking cultural and material forms of power,’ ‘Self-care as a political strategy: Refusals and ambivalence in the anti-diet community,’ and ‘Relational strategies: Challenging diet culture in work and everyday interactions.’ Participants viewed diet culture as being reinforced through internalized multi-institutional patriarchal, Eurocentric and capitalist systems. They challenged cultural norms and institutions that reinforce diet culture by being critical of gender norms and rejecting consumerist dieting practices. We argue that the self-care and relational strategies used by participants across communities signify an awkward but unified ‘anti-diet movement.’ Future research should recruit a more culturally and ethnically diverse sample and examine the ‘anti-diet’ movement beyond the Global North context