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Biomolecules play important roles in physiological functions and pharmacological characteristics of human body. Uric acid (UA) is the end product of purine. Dopamine (DA) is a neurotransmitter of catecholamine group. l-tryptophan is an essential amino acid that can be metabolized to neuroactive substances. Pyridoxine is a water-soluble vitamin playing an important role in nervous system. The abnormalities in their concentration levels led to a wide range of significant mental and physical illnesses. Thus, electrochemical analysis of these analytes on an array system would be beneficial from clinical or scientific points of view. This work was aimed at the development of practical sensor array for determination of multiple analytes on a single sensing platform using individually addressable microelectrodes. The occurrence of adsorption–desorption phenomenon on the surface of palladium microelectrode array (Pd MEA) printed on the silicon wafer through photolithography was exploited for electro-oxidation of UA, DA, l-tryptophan and pyridoxine. The sensing of electroactive UA was done using carbon nanotubes(CNTs) grown Pd MEA as a working electrode, while selectivity for other analytes was achieved by the modification of CNTs/Pd MEA through electrodeposition of poly(l-lysine) (poly(l-lysine)/CNTs/Pd MEA) for DA sensing, poly(l-arginine) (poly(l-arginine)/CNTs/Pd MEA) for l-tryptophan sensing and reduced graphene oxide (rGO/CNTs/Pd MEA) for pyridoxine sensing. The electrochemical differential pulse voltammetry (DPV) analyses reveal excellent linearity in the concentration ranges of 50–6000 µmol/L, 2–8000 µmol/L, 20–15,000 µmol/L, and 10–5000 µmol/L with detection limits of 15.0, 0.5, 10.0, and 1.0 µmol/L for UA, DA, l-tryptophan, and pyridoxine, respectively. The proposed multiple analytes sensor has shown very high sensitivities of 140, 9580, 2280, and 940 µA·(µmol·L−1)−1·cm−2for UA, DA, l-tryptophan, and pyridoxine sensing, respectively. Further, accuracy and reliability of the fabricated sensor were also tested in real samples.

The successful isolation of single layers from two-dimensional (2D) van der Waals (vdW)-layered materials has opened new frontiers in condensed matter physics and materials science. Their discovery and unique properties laid the foundation for exploring 1D counterparts. However, the isolation of 1D vdW-wired materials has thus far remained a challenge, and effective techniques are demanded. Here we report the facile synthesis of isolated transition-metal monochalcogenide MoTe nanowires by using carbon nanotubes (CNTs) as molds. Individual nanowires are perfectly separated by CNTs with a minimal interaction, enabling detailed characterization of the single wires. Transmission electron microscopy revealed unusual torsional motion of MoTe nanowires inside CNTs. Confinement of 1D vdW-wired materials to the nanotest tubes might open up possibilities for exploring unprecedented properties of the nanowires and their potential applications such as electromechanical switching devices.

In this paper, we develop a game theory model in which freight service providers seek to maximize their expected utility by competing for business from shippers and also investing in security. The focus is on high-value cargo, which has been the target of attacks globally. Shippers reflect their preferences for freight service providers through the prices they are willing to pay which depend on quantities shipped and security levels invested in. The Nash Equilibrium is formulated as a variational inequality problem for which existence is guaranteed. Numerical examples illustrate the framework and give essential freight security investment policy related information.

Workforce flexibility in regard to the time and location of work can offer many advantages for individuals, businesses, communities and countries. Whilst neither universally viable nor uniformly valuable, there are those who may have a preference for such flexibility and there is certainly untapped positive potential to be explored across multiple impact categories. The COVID 19 pandemic has improved acceptability from both employee and employer perspectives and delivered a global ‘crash course’ in remote working. The varied potentials to work from anywhere, as well as differences in associated impact outcomes point to the value of targeted supports and careful planning. The Working from Anywhere Index (WFAI) offers a transferable fine scale spatial methodology to identify both the preferences and potential for working from anywhere. The value for policy support is demonstrated through application to a case country, Ireland, where illustrative scenarios explore the role of broadband provision, the placement of remote working hubs and the effect of shifts in employment types on the preferences and potential for working from anywhere. Impact analysis indicates that the scale of annual benefits for a plausible ‘2 day a week’ national working from anywhere scenario are substantial and offer the potential to save in the region of 1 bn car commuting kilometres per annum with associated societal benefits for emissions reduction and individual time savings.