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The self-healing of cracks via biomineralization in bacteria-based concrete has shown remarkable results in recent decades. This novel technique uses the ability of bacteria to precipitate CaCO3 for sealing cracks, and is termed microbially induced calcite precipitation (MICP). However, most previous studies focused on extensive laboratory-based procedures before incorporating them into concrete. This investigation developed a ready-to-use silica fume (SF) based bacterial agent that can be used directly to achieve CaCO3 precipitation. This will aid in the use of MICP for field-scale repair in concrete structures. Furthermore, most previous studies addressed crack remediation in the horizontal orientation of concrete structures. This study developed a remediation strategy to repair realistic cracks in existing concrete structures. The developed SF-based inoculum at an age of 180 days stored at 4°C was used to design biocementitious grouts. Various biogrouts were examined for fresh and hardened properties in order to develop the most effective biogrout. The effectiveness of the surface restored using biogrout was evaluated in terms of mechanical and watertightness properties. Microstructural analysis was conducted at the end of testing to evaluate its physicochemical attributes. The electromechanical impedance technique was used to quantify the microbial activity in the biorestored concrete during curing. The results suggested that precipitates led to the densification of pores, ultimately lowering the water permeability and the recovery of mechanical strength of the repaired specimens. Conclusively, the SF-based bacterial agent can increase MICP activity to seal cracks in actual concrete structures. [ABSTRACT FROM AUTHOR]

This study demonstrates the use of computational methods to simulate the molecular dynamics involved in hemoglobin concentration sensing, utilizing Material Studio and the TCAD Silvaco device simulator. A non-invasive and flexible Graphene/MoS2 heterostructure has been proposed for sensing hemoglobin concentration in blood samples. The findings reveal a notable shift in the wavelength-dependent refractive index and extinction coefficient, as well as significant changes in the absorption coefficient and reflectivity of the Graphene/MoS2 heterostructure in response to different hemoglobin concentrations, specifically within an approximate range of 0.3 μm to 1 μm. Moreover, the spectral response of the heterostructure demonstrates that at a particular wavelength of approximately 600 nm, a maximum response is obtained. This wavelength can be considered optimal for detecting various levels of hemoglobin using this heterostructure. The anticipated outcome is a comprehensive understanding of the fundamental principles, ultimately resulting in the development of an exceptionally sensitive platform for detecting hemoglobin concentration. [ABSTRACT FROM AUTHOR]

Synergistic effects of ectomycorrhizal (ECM) fungal inoculation and biochar augmentation on plant growth, nutrient uptake and soil enzymes were investigated. A nursery experiment was conducted to assess the influence of ECM fungi (Suillus indicus and S. sibiricus) and biochar amendment (2% v/v) on the growth of Pinus wallichiana seedlings. Mycorrhizal colonisation significantly increased in biochar-amended soil compared to without biochar. Inoculation with ECM fungi in biochar-amended soils significantly increased the growth, biomass and phosphorus and nitrogen uptake of P. wallichiana seedlings compared with control as well as without biochar. The physicochemical properties of the soil were improved due to biochar augmentation and ECM inoculation. Activities of soil enzymes such as acid phosphatase, urease, dehydrogenase and protease were significantly increased in biocharamended soil along with ECM fungal inoculation. These results suggest that combined use of ECM fungal inoculation and biochar amendment had a positive impact on growth, nutrient uptake and mycorrhizal colonisation of P. wallichiana seedlings. Also, biochar prepared from pine needles has potential for enhancing plant growth and soil fertility. Additional keywords: biochar, ectomycorrhizal fungi, nutrient uptake, Pinus wallichiana, soil enzymes, Suillus species. Received 17 March 2020, accepted 14 July 2020, published online 6 August 2020, Introduction Biochar is a material produced from the thermal conversion of organic biomass during pyrolysis under low oxygen conditions (Abbott et al. 2018). Biochar amendment can increase soil carbon reserves, [...]