Development of colorimetric cholesterol detection kit using TPU nanofibre/cellulose acetate membrane

In this study, the authors report a simple fabrication of thermoplastic polyurethane (TPU) nanofibres‐based kit for cholesterol detection. TPU is a polymer that is highly elastic, resistant to microorganisms, abrasion and compatible with blood; thus, making it a natural selection as an immobilisation matrix for cholesterol oxidase (ChOx) enzyme. The nanofibre was fabricated by electrospinning process and was characterised using scanning electron microscopy and Fourier transform‐infrared spectroscopy. ChOx was covalently immobilised on TPU nanofibre and cholesterol level/concentration was visually found using 4‐aminoantipyrine, a dye that reacts with H₂ O₂ produced from the oxidation of cholesterol by ChOx and changes colour from yellow to red. The efficacy of the nanofibre to act as a detecting substrate was compared with cellulose acetate (CA) membrane, a well‐documented enzyme immobilisation matrix. The optimisation of enzyme concentration and dye quantity were performed using standard ChOx spectrophotometric assay and the same was used in CA membrane and TPU nanofibre. The ChOx immobilised nanofibre showed good linear range from 2 to 10 mM with a lower detection limit of 2 mM and was highly stable compared to that of CA membrane. The enzyme immobilised nanofibre was further validated in serum samples.Inspec keywords: colorimetry, nanofibres, biomembranes, biosensors, nanosensors, nanofabrication, polymer fibres, elasticity, nanomechanics, biomechanics, blood, nanomedicine, biomedical equipment, enzymes, molecular biophysics, molecular configurations, biochemistry, abrasion, biomedical materials, electrospinning, scanning electron microscopy, Fourier transform infrared spectra, dyes, oxidation, spectrophotometryOther keywords: colorimetric cholesterol detection kit, TPU nanofibre‐cellulose acetate membrane, thermoplastic polyurethane nanofibres‐based kit, highly elastic polymer, microorganisms, abrasion, blood compatibility, natural selection, immobilisation matrix, cholesterol oxidase ChOx enzyme, electrospinning, scanning electron microscopy, Fourier transform‐infrared spectroscopy, TPU nanofibre, cholesterol level‐concentration, 4‐aminoantipyrine, H₂ O₂ production, oxidation, cellulose acetate membrane, enzyme immobilisation matrix, enzyme concentration, optimisation, dye quantity, standard ChOx spectrophotometric assay, enzyme immobilised nanofibre, serum samples     

Valence Charge Fluctuations and Tc Retention in Tl1?xPbxSr1+xLa1?xCuO5?y (0.0 ≤ x ≤0.5) System

Structural and x-ray photoelectron spectroscopy (XPS) studies of the Tl_1–xPb_xSr_1+xLa_1–xCuO_5–y (0.0x0.5) system have been carried out. The unit cell parameters increase with x. Irrespective of x the T_c is retained in this series and the optimum hole concentration (n_h) is maintained for x 0.5. An increase in Tl 4f and O ls binding energy with x suggests a reduction in their oxidation state. Origin of holes is discussed in terms of charge transfer between Tl, Pb and CuO₂ layers.     

Virtual environments and autism: a developmental psychopathological approach

Individuals with autism spectrum disorders supposedly have an affinity with information and communication technology (ICT), making it an ideally suited media for this population. Virtual environments (VEs) – both two‐dimensional and immersive – represent a particular kind of ICT that might be of special benefit. Specifically, this paper discusses the importance of psychological theory for VE designed for this population. I describe the contribution that different theories of autism (e.g., theory of mind, executive function, weak central coherence theory) have made and can make, as well as the potential of other non‐autism‐specific theories (e.g., embodied cognition). These technologies not only illuminate our understanding of autism, but they can also be used to develop new technologies for people without autism. So, as well as being an area of specialism, I argue that VE research in autism has extended – and will go onto – the boundaries of human–computer interaction more generally. This is because autism provides a unique window into human social communication and learning. Further, this field offers a chance for better inclusivity for individuals with autism within a digital society.     

Production of ultrafine alpha alumina powders and fabrication of fine grained strong ceramics

Hydrous alumina powders, pure, seeded with alpha alumina, containing ammonium nitrate and containing both ammonium nitrate and seeds, were prepared by hydroxide precipitation. Their crystallization and sintering behaviour were investigated and mechanical properties of the ceramics were tested. Pure hydrous alumina transformed to alpha alumina crystals, with a size of ca. 200 nm, at 1200°C, after undergoing the usual metastable phase changes during heat-treatment. The powder needed to be sintered at 1600°C to achieve a high density. The ceramic had an average grain size of ca. 9 m. Seeding lowered the transformation temperature to ca. 1120°C and caused the transformation to begin at ca. 600°C. The material could be sintered at 1500°C and had a grain size of 2 m. The nitrate, predominantly present as ammonium nitrate, lowered the transformation temperature to ca. 1150°C and altered the proportion of the intermediate phases. However, the materials still had to be sintered at 1500°C to achieve >97% density. When both seed particles and nitrate ions were present the material almost completely transformed at 950°C to uniform crystals of alpha alumina with a size <60 nm that sintered to >99% theoretical density at 1450°C. The final ceramic had a uniformly grained (<1.0 m) microstructure and exhibited strength up to 800 M Pa.     

Influence of the concentration of capping agent on synthesizing and analyses of Ceria nano-filler using modified co-precipitation technique

The pure crystalline cerium oxide (CeO₂) nanoparticles were synthesized using optimized content of Ce(NO₃)₃. 6H₂O with varying concentrations of sodium hydroxide (NaOH) (0.5, 1, 1.5, and 2 M) as a precipitation agent in presence of 2.5 wt% poly(vinylpyrrolidone) PVP. All the samples are prepared via the modified coprecipitation technique. The synthesized materials have been analyzed using X-ray diffraction (XRD), Fourier transform infrared (FT-IR), laser Raman, high-resolution scanning electron microscope (HR-SEM), and photo luminescence (PL) analyses. The optimized sample was identified with the help of the above studies that could be analyzed through transverse electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) studies. The cubic structure with the Fm-3 m space group has been confirmed through XRD (JCPDS: 81-0792) and Raman analyses. The FT-IR and energy dispersive X-ray spectroscopy (EDX) analyses ascertain the occurrence of Ce and O species. The as-prepared CeO₂ filler (0, 3, 6, 9, and 12 wt%) is dispersed through the optimized polymer electrolyte Poly (styrene-co-methyl methacrylate) P(S-MMA) (27 wt%)–lithium perchloride (LiClO₄) (8 wt%)–ethylene carbonate + propylene carbonate (EC + PC) (1;1 of 65 wt%) complex system using solution casting technique. P(S-MMA) (27 wt%)–LiClO₄ (8 wt%)–EC + PC (1;1 of 65 wt%)–6 wt% of CeO₂ shows the high ionic conductivity 8.13 × 10⁻⁴ S cm⁻¹.     

Semantic data integration in hierarchical domains

A major challenge in building the Semantic Web is resolving differences among heterogeneous databases. This article describes one approach for handling semantic data integration problems in hierarchical domains. It also describes a declarative approach for specifying pairwise mappings between a centrally maintained ontology and each local data repository maintained by an autonomous agency. In this context, it outlines a method for specifying the mappings' semantics and encoding them to resolve heterogeneities. It focuses on XML-based applications in which entities in the centrally maintained ontology are hierarchically related to those in the local data repositories.     

Year around distilled water production,energy, and economic analysis of solar stills—A comparative study

In this paper, a year around energy efficiency (EnE) and economic analysis of single slope solar still (SSSS), the single slope solar still with glass cooling (SSSSGC), the single slope solar still with basin heating (SSSSBH), and the single slope solar still with glass cooling and basin heating (SSSSGCBH) was carried out based on the distilled water production. The annual yield production from the SSSS, SSSSGC, SSSSBH, and SSSSGCBH were 476.16, 637.44, 970.24, and 1167.36 kg, respectively. The yearly yield produced from the SSSSBH and SSSSGCBH was increased by 50.92% and 59.21%, respectively, as compared with the SSSS. Moreover, the annual EnE of the SSSSGCBH was 28.75%. However, the EnE of the SSSS was 11.73%. Also, freshwater making cost is found to be 18.9, 24.9, 37.9, and 45.6 Rs/day for the SSSS, SSSSGC, SSSSBH, and SSSSGCBH, respectively, if the buying cost of freshwater is Rs 10.     

Characterisation of [(1−x)PMMA-xPVdF] polymer blend electrolyte with Li ion

The possible use of polymeric materials in thin-film solid electrolytes for battery systems, fuel cells, sensors and other electrochemical applications has stimulated worldwide interest in metal salt solvating macromolecules. Polymer electrolyte membranes comprising of poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride) (PVdF) and lithium perchlorate are prepared using a solvent casting technique. Polymer blends have been characterised by FTIR and XRD studies to determine the molecular environment for the conducting ions. The role of interaction between polymer hosts on conductivity is discussed using the results of ac impedance studies. The ionic conductivity is presented as a function of temperature and PVdF content. Room temperature conductivity of 3.14×10⁻⁵ S cm⁻¹ has been obtained for the [0.25PMMA/0.75PVdF]-LiClO₄ polymer complex.     

Microstructural modeling in f.c.c. crystalline materials in a unified dislocation-density framework

A unified physically based microstructural representation of f.c.c. crystalline materials, has been developed such that evolving microstructural behavior at different physical scales can be accurately predicted. This microstructural framework is based on coupling a multiple-slip crystal plasticity formulation to three distinct dislocation densities, which pertain to statistically stored dislocations, geometrically necessary dislocations, and grain boundary dislocations. This interrelated dislocation-density formulation is then used with specialized finite-element modeling techniques to predict the evolving heterogeneous microstructure and the localized phenomena that can contribute to failure initiation as a function of inelastic deformation.     

美国艾默生公司压缩机应用技术讲座——第三十二讲全年能效比：一种更好的制冷系统性能的量度

本文的目的是对现有的制冷空调系统的效率测量方法进行审视，并提出一种更为精确的衡量制冷系统的实际运行情况的新方法。