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Abstract Background Renal failure in diabetes is mediated by multiple pathways. Experimental and clinical evidences suggest that renin-angiotensin-aldosterone system (RAAS) has a crucial role in diabetic kidney disease. A relationship between the RAAS genotypes and chronic renal insufficiency (CRI) among type 2 diabetes subjects has therefore been speculated. We investigated the contribution of selected RAAS gene polymorphisms to CRI among type 2 diabetic Asian Indian subjects. Methods Twelve single nucleotide polymorphisms (SNPs) from six genes namely-renin (REN), angiotensinogen (ATG), angiotensin converting enzyme I (ACE), angiotensin II type 1 receptor (AT1) and aldosterone synthase (CYP11B2) gene from the RAAS pathway and one from chymase pathway were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method and tested for their association with diabetic CRI using a case-control approach. Successive cases presenting to study centres with type 2 diabetes of ≥2 years duration and moderate CRI diagnosed by serum creatinine ≥3 mg/dl after exclusion of non-diabetic causes of CRI (n = 196) were compared with diabetes subjects with no evidence of renal disease (n = 225). Logistic regression analysis was carried out to correlate various clinical parameters with genotypes, and to study pair wise interactions between SNPs of different genes. Results Of the 12 SNPs genotyped, Glu53Stop in AGT and A>T (-777) in AT1 genes, were monomorphic and not included for further analysis. We observed a highly significant association of Met235Thr SNP in angiotensinogen gene with CRI (O.R. 2.68, 95%CI: 2.01–3.57 for Thr allele, O.R. 2.94, 95%CI: 1.88–4.59 for Thr/Thr genotype and O.R. 2.68, 95%CI: 1.97–3.64 for ACC haplotype). A significant allelic and genotypic association of T>C (-344) SNP in aldosterone synthase gene (O.R. 1.57, 95%CI: 1.16–2.14 and O.R. 1.81, 95%CI: 1.21–2.71 respectively), and genotypic association of GA genotype of G>A (-1903) in chymase gene (O.R. 2.06, 95%CI: 1.34–3.17) were also observed. Conclusion SNPs Met235Thr in angiotensinogen, T>C (-344) in aldosterone synthase, and G>A (-1903) in chymase genes are significantly associated with diabetic chronic renal insufficiency in Indian patients and warrant replication in larger sample sets. Use of such markers for prediction of susceptibility to diabetes specific renal disease in the ethnically Indian population appears promising.

The electrochemical corrosive processes compromise the passivity of reinforcing steel, potentially leading to structural integrity loss and, in extreme cases, concrete infrastructure failures. While bio-inspired concretes show promise in mitigating strength degradation and enabling self-healing of concrete flaws, their interaction with steel reinforcement remains underexplored. Thus, this investigation aimed to establish a protective strategy by fostering biofilm growth on rebar surfaces. To achieve this, Bacillus subtilis and Escherichia coli bacteria were utilized as biofilm-forming agents, aided by magnetic iron oxide and zeolite micro-nano particles. The study encompassed a thorough assessment of split tensile strength, corrosion resistance of bio-treated embedded steel bars, and a comprehensive biofilm characterization, along with a meticulous examination of the microstructure at the steel-concrete interface. The findings underscored a significant improvement in split tensile strength, demonstrating a remarkable 84.2 % increase when bacterial species were combined with iron oxide nanoparticles, in contrast to the control specimens. Furthermore, the bio-treated bars exhibited an impressive corrosion inhibition potential of 78.5 % relative to their unaltered counterparts. These outcomes are attributed to the discernible refinement of microstructural features surrounding the steel reinforcement and the heightened densification of the inter-transitional zone between steel and concrete.

The strain hardening fiber reinforced concrete—generally known as the Engineered Cementitious Composite (ECC)—has rapidly gained the attention of researchers in recent years. However, most of the research on ECC is limited to material and member level, leaving a gap in the understanding of its behavior at the structural scale. Therefore, this study investigates the global seismic response of ECC structures and compares their performance with conventional reinforced concrete (RC) structures. For this purpose, a case study long span building structure (an aircraft hangar having a span length of 40 m) is selected. Under the design-level gravity and lateral loads, its members are separately designed using the conventional RC and ECC. It is observed that for ECC members, the requirement of longitudinal steel is reduced by 30% when compared with the conventional RC members. Similarly, owing to an improved tensile behavior, the ECC members also exhibited a higher shear capacity than RC members, resulting in a significant reduction in the requirement of transverse reinforcement. The detailed inelastic finite element models for both design cases (RC and ECC) were subjected to the pushover analysis and nonlinear response history analysis (NLRHA) to assess their seismic performance. It is observed that (in terms of local and global seismic demands, structural damage, and ductile behavior) the performance of the ECC structure is significantly improved when compared to the conventional RC structure. The comparative cost analysis showed a reduction of 11.9% in the overall material cost of the ECC structure as compared to RC. These results show that ECC can be effectively used at the full structural level as an economic solution to ensure the ductile response and superior seismic performance.

The construction industry is responsible for around 5% of total CO2 emissions globally. As a result, recent research is focused on the sustainability aspects of construction materials. Engineered cementitious Composites (ECC) are high-performance fiber reinforced composites with improved ductility and tensile strength but utilize higher cement content, raising concerns about their sustainability. In this study, nano-lime and calcined clay are combined with cement to develop a high strength sustainable nano lime calcined clay cement (nLC3) based Engineered Cementitious Composite (ECC). Initially, the packing density model was employed to develop a high strength nLC3-based matrix by combining the particle packing models and chemical compatibility while keeping costs to a minimum. Micromechanical modeling was then applied to determine the critical volume of fibers for the novel matrix using single fiber pullout tests and matrix toughness tests. According to the micromechanical model, the critical volume fraction is found to be 1.93% for the nLC3 mix. This was further confirmed by casting dog bone samples containing 2% fibers by volume which confirmed strain hardening response. The uniaxial test results indicated a strength of around 5.85 MPa in tension and 51 MPa in compression with about 3% tensile strain. These results are comparable to conventional ECC and better than previously developed LC3 based ECC. This study reveals that nLC3-based ECC is a more sustainable composite as compared to conventional ECC mix without any compromise on strength and cost.

Fiber reinforced concrete (FRC) is attracting many researchers' attention due to its excellent mechanical and fracture properties. However, its widespread implementation is hampered by the issues related to the dispersion and orientation of its fibers. According to the fracture mechanics, the reinforcement would provide maximum bridging when placed perpendicular to the crack propagation. This study is focused on the magnetic-based orientation of synthetic fibers which are mostly used in strain hardening FRC also termed as Engineered Cementitious Composites (ECC). Initially, the PVA fibers were coated with waste iron particles using a hydrothermal synthesis procedure. This was done to make synthetic fibers magnetically responsive by the formation of a physical bond between iron and PVA fibers. A solenoid was used to provide a high-intensity magnetic flux to orient these fibers in the direction of magnetic lines. Three different ECC mixes were prepared and cast in wooden molds. The molds were then placed one by one into the magnetic field for the orientation of the fibers. The fibers were successfully aligned perpendicular to the flexure cracks in only flexure dominant regions with the aid of a magnetic field. The orientation of fibers was verified with the help of microscopic images of the tortured surfaces. As a result of well aligned fibers dispersed in the ECC mix, the flexural strength was increased by 21%.

The global construction industry is shifting toward eco-friendly building materials to reduce environmental impact while ensuring affordability, energy efficiency, and resource conservation. Interlocking compressed earthen bricks (ICEBs) offer a sustainable alternative to traditional bricks. However, ICEB composition significantly impacts their performance. This study investigates the interplay of stabilizer, water, and fine aggregate content to optimize ICEBs. Soil properties were assessed through particle size gradation analysis, Atterberg limits, and the modified Proctor test. ICEBs were manufactured using cement as a stabilizer, with various combinations of stabilizer proportions, water-to-soil ratios, and inclusion of fine aggregates. Compressive strength tests were conducted for each mix. Results showed that increased cement content enhanced ICEB compressive strength by promoting the formation of calcium silicate hydrate gel. Water content increments from 12% to 21% improved strength up to 18% but declined thereafter. Higher sand percentages initially reduced compressive strength but improved it with higher cement proportions. The optimal mix ratio was selected for ICEB production, followed by tests including flexural strength assessment, forensic investigations, curing regimes impact, and comprehensive durability and structural performance evaluation. Findings highlight ICEBs’ potential as a sustainable alternative to conventional brick masonry.

In nonstructural infill panels, common materials like expanded polystyrene panels face fire susceptibility, autoclaved aerated concrete (AAC) incurs high production costs, and traditional bricks come with a significant carbon footprint and weight. So, there is a requirement for infill panels that are not just resilient and lightweight but sustainable as well. This study seeks to address these issues by introducing sustainable and lightweight expanded clay aggregate (ECA) in concrete. Firstly, eight ECA mix designs were prepared by integrating fly ash and kerosene with clay, and ECA with a bulk density of 0.59 g/cm³ and compressive strength of up to 1.73 MPa were prepared. The lightest ECA mix was then chosen to explore their use in lightweight aggregate concrete (LWAC) along with fly ash as a secondary cementitious material. The resulting LWAC had a minimum density of 1,050 kg/m³ and a compressive strength of 6.8 MPa, fulfilling the standard requirements of a minimum of 3.5 MPa for nonstructural concrete.

Urbanization, industrialization, and economic growth all contribute to the rising demand for bricks. The world is heading towards sustainable, eco-friendly, recyclable materials to enhance the circular economy and mitigate the issues of carbon footprint, overburdened landfills, and waste of natural resources. Therefore, the mix design of bricks has evolved with time by incorporating recycled waste materials, i.e., glass, etc. This paper presents a unique approach to developing machine learning models to predict the mechanical properties of eco-efficient bricks incorporating waste glass, as it requires extensive experimentation to comprehend the properties. This research assesses four essential input parameters affecting mechanical properties. To predict the outcomes, four machine learning models were generated, and their results were compared. These four models include artificial neural networks (ANN), the Gaussian process of regression (GPR), the classification and regression tree (CART), and the support vector machine (SVM). A unique and advanced approach known as the generative adversarial network (GAN) has been employed for augmenting data and enhancing accuracy as the data available in published literature were limited. As a result, artificial neural network (ANN) has the highest accuracy among all models. Therefore, it is the most efficient model with RMSE and R2 of 3.86 MPa and 0.81 for predicting the compressive strength, and RMSE and R2 of 0.82 % and 0.995 for predicting the Shrinkage of bricks incorporating glass. This study proposes a distinctive tool using machine learning for the sustainable brick production sector via predicting the mechanical properties of brick incorporating waste glass.

Compressive strength determination of high-performance concrete (HPC) is necessary for its practical usage. However, experimental testing for this purpose is resource intensive and time-consuming. Recently, machine learning has emerged in this field, especially data-driven modeling. In this study, a novel hybrid model for the compressive strength prediction of HPC is developed using the cascade forward neural network (CFNN) and artificial bee colony (ABC) optimization. The hybrid model used the ABC optimization method to select the optimal architecture of the neural network. A comprehensive database of 2171 data points containing information about cement, blast furnace slag, fly ash, water, coarse aggregate, sand, and age as input variables, and compressive strength as output variable is used to develop the model. Results indicated that the optimal neural network architecture selected by the ABC method consists of 2 layers and the developed model (CFNN-ABC) could accurately predict the compressive strength of HPC with correlation (R) and determination coefficients (R2) of 0.976 and 0.953, respectively. The feature importance of the model revealed that the cement and sand were more influential features as compared to the other features. The partial dependence analysis demonstrated the effect of variation in input parameters on the attained compressive strength. Furthermore, the model validation with previously developed models using performance indices showed that the proposed hybrid model outperformed other models in all performance indices including root mean square error (RMSE ∼ 4.04) and mean absolute error (MAE ∼ 3.10). Therefore, the present work provides a novel and efficient option to predict the compressive strength of HPC which can aid in the design of sustainable infrastructures without going through costly and time-intensive experimentation.

Due to an increase in global warming, the construction industry, like the rest of the world is turning towards sustainable solutions. The construction industry is the major contributor to global warming primarily due to the use of cement. Geopolymer is an eco-friendly construction material that utilizes zero cement for its production. However, the major issue that limits its commercial implementation is its complex mix design, which is not as straightforward as conventional concrete. As geopolymer contains more elements than conventional concrete, its mix design process is more challenging. Alongside there are no defined guidelines for material designing of geopolymer concrete, which makes the task of designing it quite time-consuming, uneconomical, and iterative. The objective of this research is to develop a machine learning model that can predict the mechanical and rheological properties of geopolymer concrete. An Artificial Neural Network-based model was developed, which takes the input of the mix's constituents and predicts both mechanical and rheological properties as a result. MAE (Mean square error) for compressive strength, elastic modulus, flexural strength, and slump value for a training set were 2.53, 0.72, 0.121, and 8.9, respectively, while MAE for the testing set was 4.32, 1.5, 0.65, and 19.7. These performance results of MAE seem excellent to be used for prediction. This paper will help in the effective design of geopolymer concrete with limited experimentation.

Summary Microbially induced calcite precipitation (MICP), secreted through biological metabolic activity, secured an imperative position in remedial measures within the construction industry subsequent to ecological, environmental and economical returns. However, this contemporary recurrent healing system is susceptible to microbial depletion in the highly alkaline cementitious environment. Therefore, researchers are probing for alkali resistant calcifying microbes. In the present study, alkaliphilic microbes were isolated from different soil sources and screened for probable CaCO3 precipitation. Non‐ureolytic pathway (oxidation of organic carbon) was adopted for calcite precipitation to eliminate the production of toxic ammonia. For this purpose, calcium lactate Ca(C3H5O3)2 and calcium acetate Ca(CH3COO)2 were used as CaCO3 precipitation precursors. The quantification protocol for precipitated CaCO3 was established to select potent microbial species for implementation in the alkaline cementitious systems as more than 50% of isolates were able to precipitate CaCO3. Results suggested 80% of potent calcifying strains isolated in this study, portrayed higher calcite precipitation at pH 10 when compared to pH 7. Ten superlative morphologically distinct isolates capable of CaCO3 production were identified by 16SrRNA sequencing. Sequenced microbes were identified as species of Bacillus, Arthrobacter, Planococcus, Chryseomicrobium and Corynebacterium. Further, microstructure of precipitated CaCO3 was inspected through scanning electron microscopy (SEM), X‐ray diffraction (XRD) and thermal gravimetric (TG) analysis. Then, the selected microbes were investigated in the cementitious mortar to rule out any detrimental effects on mechanical properties. These strains showed maximum of 36% increase in compressive strength and 96% increase in flexural strength. Bacillus, Arthrobacter, Corynebacterium and Planococcus genera have been reported as CaCO3 producers but isolated strains have not yet been investigated in conjunction with cementitious mortar. Moreover, species of Chryseomicrobium and Glutamicibacter were reported first time as calcifying strains.

In this paper performance of graphite nano platelets and carbon nanotubes was investigated in both conventional as well as self-compacting mortar. Workability, linear-shrinkage, rheological properties, flexural and compressive strength, air content and water absorption tests were conducted. Results reveal that by addition of nano media in cement matrix workability, shrinkage, air content, and water absorption adamantly reduces as compared to control mixtures. On the other hand yield stress, plastic viscosity, compressive and flexural strength enhances significantly. The shrinkage response of SCM-3 and CCM-3 depicts reduction of 66% and 61% respectively. Furthermore, yield stress and plastic viscosity increase 53% and 12% respectively. By addition of nano media deviation in crack propagation, more nucleation sites, capturing the micro voids, filling the pores and dense packing of the hydrated products were found. Increase in compressive strength and flexural strength was observed. Hence hybrid nano media can be intruded as a potential candidate in cement matrix for enhancing the structural properties. Keywords: Linear shrinkage, Rheological properties, Stress strain response, Air content, Water absorption and microstructure

Purpose: The purpose of this paper is to determine the impact of management control systems such as self-control and organization’s norms on the sustainability of an organization with mediating role of corporate social responsibility (CSR) practices. The study focused on small and medium enterprises in the agricultural sector and how they can be sustainable by using these factors. Design/Methodology/Approach: This is a primary study based on quantitative data. The non-probability, convenience sampling is used. The research design includes hypotheses testing whether they are accepted or rejected. Data collection was done through closed-ended questionnaires with a Likert scale. The chosen sample size was 200 however, 184 questionnaires were received back after filling. Smart PLS was used for data analysis. Findings: Based on the analysis, all the hypotheses were accepted which show that there is indeed an impact of management control systems and organizations norms on an organization’s sustainability and CSR practices play the role of mediator. Implications/Originality/Value: Originality this study is testing the mediating effect of CSR practices on control systems, organizations norms and sustainability of the firm in the agricultural sector of Pakistan where small and medium enterprises related to the agricultural sector are targeted. There are very few researches that focused on SME’S in the agricultural sector of Pakistan, this study provided a detailed insight into this sector. The study will be of great value to agricultural and SME’s owners on how they can create sustainability in their firm.

The precise evaluation of the potential damage caused by large commercial aircraft crash into civil structures, especially nuclear power plants (NPPs), has become essential design consideration. In this study, impact of Boeing 767 against rigid wall and outer containment building (reinforced concrete) of an NPP are simulated in ANSYS/LS-DYNA by using both force time history and missile target interaction methods with impact velocities ranging from 100 m/s to 150 m/s. The results show that impact loads, displacements, stresses for concrete and steel reinforcement, and damaged elements are higher in case of force time history method than missile target interaction method, making the former relatively conservative. It is observed that no perforation or scabbing takes place in case of 100 m/s impact speed, thus preventing any potential leakage. With full mass of Boeing 767 and impact velocity slightly above 100 m/s, the outer containment building can prevent local failure modes. At impact velocity higher than 120 m/s, scabbing and perforations are dominant. This concludes that in design and assessment of NPP structures against aircraft loadings, sufficient thickness or consideration of steel plates are essential to account for local failure modes and overall structural integrity. Furthermore, validation and application of detail 3D finite element and material models to full-scale impact analysis have been carried out to expand the existing database. In rigid wall impact analysis, the impact forces and impulses from FE analysis and Riera's method correspond well, which satisfies the recommendations of relevant standards and further ensure the accuracy of results in full-scale impact analysis. The methodology presented in this paper is extremely effective in simulating structural evaluation of full-scale aircraft impact on important facilities such as NPPs.

After fire exposure the reinforced concrete structures lose strength and durability. Mapping the damage caused by fire exposure becomes extremely important to assess the serviceability of a fire exposed building. This case study covers in brief the structural health assessment of a fire damaged structure. To unravel the heating history various techniques were adopted. Non-destructive testing (NDT) methods were employed to assess the residual durability properties. Similarly, core extraction tests were performed to evaluate the residual mechanical properties. Further, a framework was developed with the help of microstructural and thermal analyses to reasonably estimate the exposure temperatures of various structural units. This methodology has efficiently predicted the degraded quality of Reinforced concrete based on Microstructural Structural Analysis and Non-Destructive Testing. Keywords: Non-destructive testing, Structural heath assessment, Ultrasonic pulse velocity, Microstructural analysis, Compressive strength

Lately a strong correlation has been established between diet and cancer. For ages, cumin has been a part of the diet. It is a popular spice regularly used as a flavoring agent in a number of ethnic cuisines. In the present study cancer chemopreventive potentials of different doses of a cumin seed-mixed diet were evaluated against benzo(a)pyrene [B(a)P]-induced forestomach tumorigenesis and 3-methylcholanthrene (MCA)-induced uterine cervix tumorigenesis. Results showed a significant inhibition of stomach tumor burden (tumors per mouse) by cumin. Tumor burden was 7.33 ± 2.10 in the B(a)P-treated control whereas it reduced to 3.10 ± 0.57 (P < 0.001) by a 2.5% dose and 3.11 ± 0.60 (P <0.001) by a 5% dose of cumin seeds. Cervical carcinoma incidence, compared with the MCA-treated control group (66.67%), reduced to 27.27% (P < 0.05) by a diet of 5% cumin seeds and to 12.50% (P < 0.05) by a diet of 7.5% cumin seeds. The effect of 2.5 and 5% cumin seed-mixed diets was also examined on carcinogen/xenobiotic metabolizing phase I and phase II enzymes, antioxidant enzymes, glutathione content, lactate dehydrogenase (LDH), and lipid peroxidation in the liver of Swiss albino mice. Levels of cytochrome P-450 (cyt P-450) and cytochrome b5 (cyt b5) were significantly augmented (P < 0.05) by the 2.5% dose of cumin seed diet. The levels of cyt P-450 reductase and cyt b5 reductase were increased (significance level being from P < 0.05 to P < 0.01) by both doses of cumin. Among the phase II enzymes, glutathione S-transferase specific activity increased (P < 0.005) by the 5% dose, whereas that of DT-diaphorase increased significantly (P < 0.05) by both doses used (2.5 and 5%). In the antioxidant system, significant elevation of the specific activities of super-oxide dismutase (P < 0.01) and catalase (P < 0.05) was observed with the 5% dose of cumin. The activities of glutathione peroxidase and glutathione reductase remained unaltered by both doses of cumin. The level of reduced elutathione measured as nonprotein sulfhydryl content was elevated (significance level being from P < 0.05 to P < 0.01) by both doses of cumin. Lipid peroxidation measured as formation of MDA production showed significant inhibition (P < 0.05 to P < 0.01) by both doses of cumin. LDH activity remained unaltered by both doses of cumin. The results strongly suggest the cancer chemopreventive potentials of cumin seed and could be attributed to its ability to modulate carcinogen metabolism. [ABSTRACT FROM AUTHOR]

For preserving concrete structures and hindering ingress of chemicals through cracks and fissures, repair is inevitable. Microbial calcite precipitation is an intrinsic approach for crack rectification and emulating way of sustainability for reducing anthropogenic greenhouse gases (GHGs) along with conserving the natural resources. In this study, Bacillus subtilis strain is applied for intrinsic repair of concrete’s cracks because of its high pH endurance and capability of sporulation. For prolonged survival of microorganisms, immobilization technique was employed. B. subtilis was immobilized through limestone powder (LSP) before adding into cement matrix. Self-healing proficiency of B. subtilis was deliberated in terms of mechanical strength regain after cracking at 3, 7, 14, and 28 days. To examine the microstructure and characterization of healing precipitate, micrographical (field emission scanning electron microscopy), chemical (energy dispersive X-ray), and thermal (thermogravimetric analysis) analyses were performed after the healing period of 28 days. The results revealed evident signs of calcite precipitation in nano-/microcracks subsequent to microbial activity. Furthermore, immobilized LSP improved the compressive strength of the analyzed formulations.