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The construction industry is looking for sustainable and cost-effective alternatives to conventional building materials. As the world faces increasing environmental challenges, the need for greener construction practices has become more urgent. Cement production is known for its high energy consumption and significant carbon dioxide emissions. Therefore, it is essential to find ways to reduce the environmental impact of cement production and use. One promising area of research is the use of industrial byproducts such as steel slag to partially replace cement in concrete. The use of these by-products not only solves the problem of waste disposal but also provides a sustainable solution to improve the properties of building materials. When mixed with cement, steel slag participates in pozzolanic reactions, in which reactive silica from the slag reacts with calcium hydroxide, produced during the hydration of cement, to form calcium silicate hydrate gel (CSH). This CSH gel is responsible for the strength and durability of concrete. Incorporating steel slag can improve the mechanical properties of concrete, including compressive, flexural, and tensile strength. In addition, steel slag can improve the durability properties of concrete, such as resistance to chemical attack, reduced permeability, and increased resistance to physical and chemical degradation over time. This paper investigates the durability properties of cement when partially replaced by steel slag, focusing on various aspects of durability, including resistance to chemical attack, mechanical strength, and long-term performance under various environmental conditions. The study includes a comprehensive experimental program designed to evaluate the impact of steel slag on the durability of concrete through a series of tests and analyses. [ABSTRACT FROM AUTHOR]

The establishment of many industries produces a large amount of by-products in solid, semi-solid, and liquid form because industrial waste can be toxic or non-toxic in nature, causing serious damage to the environment. India has a vast network of existing industries, and in the future, many more will produce millions of tons of various by-product materials. Pollution and disposal problems can be reduced by using these materials effectively in civil engineering projects. This paper examined the evaluation of red mud produced in the alumina processing industry to determine its suitability as a construction material based on physical, chemical, and other civil engineering properties. Red mud is the fine-grained residue that remains after alumina has been extracted from bauxite ore. About 10 million metric tons of red mud waste is generated every year in India, causing very serious and alarming environmental problems. Neutralizing this red mud would be very beneficial, as it would reduce pollution. In addition, the neutralized red mud could be reused in construction mixes and as a raw material. The physical, chemical, and geotechnical characteristics of these waste materials were critically evaluated for this purpose. It was found that red mud can be used as building material. [ABSTRACT FROM AUTHOR]

The dipole-multipole transition in rapidly rotating dynamos is investigated through the analysis of forced magnetohydrodynamic waves in an unstably stratified fluid. The focus of this study is on the inertia-free limit applicable to planetary cores, where the Rossby number is small not only on the core depth but also on the length scale of columnar convection. By progressively increasing the buoyant forcing in a linear magnetoconvection model, the slow magnetic-Archimedean-Coriolis (MAC) waves are significantly attenuated so that their kinetic helicity decreases to zero; the fast MAC wave helicity, on the other hand, is practically unaffected. In turn, polarity reversals in low-inertia spherical dynamos are shown to occur when the slow MAC waves disappear under strong forcing. Two dynamically similar regimes are identified - the suppression of slow waves in a strongly forced dynamo and the excitation of slow waves in a moderately forced dynamo starting from a small seed field. While the former regime results in polarity reversals, the latter regime produces the axial dipole from a chaotic multipolar state. For either polarity transition, a local Rayleigh number based on the mean wavenumber of the energy-containing scales bears the same linear relationship with the square of the peak magnetic field measured at the transition. The self-similarity of the dipole-multipole transition can place a constraint on the Rayleigh number for polarity reversals in the Earth. [ABSTRACT FROM AUTHOR]

This article discusses the limitations of vibration controlled transient elastography (VCTE) in the evaluation of liver fibrosis in the setting of living donor liver transplantation (LDLT). The authors present a case study of a 21-year-old male who underwent LDLT and experienced graft dysfunction. Despite high liver stiffness measurements (LSM) suggestive of advanced fibrosis, further evaluations including liver biopsy showed no evidence of fibrosis or rejection. The authors highlight the importance of considering the eccentric location of the liver in LDLT settings as a potential limitation of VCTE, particularly in cases involving left lobe graft recipients and right lobe donors. [Extracted from the article]

The evolution of a buoyancy disturbance in a stratified incompressible fluid permeated by a uniform vertical magnetic field is investigated. Two regimes are considered in the absence of background rotation – that of strong stratification, where the internal gravity wave frequency $\omega _A$ is much higher in magnitude than the magnetic (Alfvén) wave frequency $\omega _M$ , and that of strong magnetic field, where $\omega _M$ is dominant. For small but finite magnetic diffusion, perturbations that initially lie in the strong-field regime are shown to cross over to the regime of strong stratification, so that small-scale motions may exist as damped internal gravity waves at large times. The induced magnetic field propagates as damped Alfvén waves for a much longer time than the velocity before undergoing the above transition. With strong rotation, the unstably stratified system that satisfies the inequality $|\omega _C| > |\omega _M| \gg |\omega _A| \gg |\omega _\eta |$ , where $\omega _C$ is the inertial wave frequency and $\omega _\eta$ is the diffusion frequency, is of relevance to convection-driven dynamos. Here, a parameter space with $|\omega _M/\omega _C| \sim 0.1$ is found wherein the flow intensity of the slow magnetic-Archimedean-Coriolis (MAC) waves is of the same order of magnitude as that of the fast MAC waves. Slow wave motions at horizontal length scales much smaller than the width of the fluid layer can therefore generate substantial helicity in rapidly rotating dynamos. The excitation of slow MAC waves at scales of $\sim$ 10 km in the Earth's core may play a crucial role in the generation of the axial dipole field. [ABSTRACT FROM AUTHOR]

Acute gastric volvulus associated with congenital diaphragmatic hernia is an unusual surgical emergency and its presentation in adulthood is extremely rare. Gastric volvulus is an uncommon condition which is difficult to diagnose and treat. This case describes a middle aged man presenting with post-traumatic acute abdomen and finally being diagnosed as a case of gastric volvulus due to congenital diaphragmatic hernia which was till now asymptomatic and undiagnosed. Clinical examination and chest x-ray was suggestive of hiatus hernia. Contrast-enhanced CT of thorax and abdomen revealed hiatus hernia and gastric volvulus. A provisional diagnosis of post-traumatic hiatus hernia with associated gastric volvulus was made and was operated on an emergency basis. Surprisingly, the intraoperative findings revealed significant adhesions near the diaphragm suggestive of congenital diaphragmatic hernia. Hence, a diagnosis of gastric volvulus due to congenital diaphragmatic hernia was made which remained asymptomatic and undiagnosed till adulthood. He responded well to operative management and remained asymptomatic afterwards. [ABSTRACT FROM AUTHOR]

Cirrhotic or hepatic myelopathy is a rare neurological complication of chronic liver disease usually seen in adults and presents as a progressive pure motor spastic paraparesis which is usually associated with overt liver failure and a surgical or spontaneous systemic portocaval shunt. We describe the development of progressive spastic paraparesis, in a patient with alcoholic cirrhosis with portal hypertension and portal colopathy who presented with the first episode of hepatic encephalopathy. The patient had not undergone any shunt procedure. [ABSTRACT FROM AUTHOR]

Scattering of a time-harmonic anti-plane shear wave due to either a pair of crack tips or a pair of rigid constraint tips on square lattice is considered. The two problems correspond to the so-called zero-offset case of scattering due to a pair of identical Sommerfeld screens. The peculiar structural symmetry allows the reduction of coupled equations to two scalar Wiener-Hopf equations and a total of four geometrically reduced problems on lattice half-plane. Exact solution of each problem for incidence from the bulk lattice, as well as from an associated lattice waveguide, is constructed. A suitable superposition of the four expressions is used to construct the solution of the main problem. The discrete paradigm involving the wave mode incident from the waveguide is relevant for modern applications where an investigation of mechanisms of electronic and thermal transport at nanoscale remains an interesting problem. This article is part of the theme issue 'Modelling of dynamic phenomena and localization in structured media (part 2)'.