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The sodium/proton exchanger-3 (NHE3) plays a major role in acid–base and extracellular volume regulation and is also implicated in calcium homeostasis. As calcium and phosphate balances are closely linked, we hypothesized that there was a functional link between kidney NHE3 activity, calcium, and phosphate balance. Therefore, we examined calcium and phosphate homeostasis in kidney tubule–specific NHE3 knockout mice (NHE3loxloxPax8mice). Compared to controls, these knockout mice were normocalcemic with no significant difference in urinary calcium excretion or parathyroid hormone levels. Thiazide-induced hypocalciuria was less pronounced in the knockout mice, in line with impaired proximal tubule calcium transport. Knockout mice had greater furosemide-induced calciuresis and distal tubule calcium transport pathways were enhanced. Despite lower levels of the sodium/phosphate cotransporters (NaPi)-2a and -2c, knockout mice had normal plasma phosphate, sodium-dependent 32Phosphate uptake in proximal tubule membrane vesicles and urinary phosphate excretion. Intestinal phosphate uptake was unchanged. Low dietary phosphate reduced parathyroid hormone levels and increased NaPi-2a and -2c abundances in both genotypes, but NaPi-2c levels remained lower in the knockout mice. Gene expression profiling suggested proximal tubule remodeling in the knockout mice. Acutely, indirect NHE3 inhibition using the SGLT2 inhibitor empagliflozin did not affect urinary calcium and phosphate excretion. No differences in femoral bone density or architecture were detectable in the knockout mice. Thus, a role for kidney NHE3 in calcium homeostasis can be unraveled by diuretics, but NHE3 deletion in the kidneys has no major effects on overall calcium and phosphate homeostasis due, at least in part, to compensating mechanisms.

A stoichiometric cubic phase of zinc bismuth oxide ZnBi38O60(ZBO) is introduced as an anode for rechargeable Na-ion batteries. ZBO is synthesized using a coprecipitation method and characterized by various physicochemical techniques. Pristine ZBO shows a high cyclability in an ether-based electrolyte due to the formation of a robust interphase coupled with high Na+conductivity. Fast charge-transfer kinetics and high chemical compatibility between the electrolyte and electrode result in a high reversible stable capacity of ∼300 mA h/g at 100 mA/g and ∼180 mA h/g at 1000 mA/g for the as-synthesized ZBO. Using in situ diffraction (XRD) experiments, both conversion and alloying reactions are found to be responsible for the observed good performance. A robust, multilayered SEI composed of an inner bismuth-rich inorganic layer and an outer polyether layer with high ionic conductivity is observed using X-ray photoelectron spectroscopy analysis. The battery characteristics are found to be superior to the individual binary oxides, Bi2O3and ZnO, thus bringing out the advantages of the addition of zinc and the ternary system studied. Preliminary full cell studies with the ZBO anode and Na3V2(PO4)3cathode show good performance with high energy density and stability. The present investigations reveal a great potential for the anode, ZBO, comprising earth-abundant elements, and will likely lead to an alternate anode material for rechargeable batteries.

Mg-Zn-Ca alloy is a promising candidate for orthopaedic implants such as bone plates and screws, as it has a similar mechanical strength and elastic modulus to bone, and it degrades in the body without causing toxicity or inflammation. Drilling studies are necessary to optimize the drilling process parameters, to evaluate the machinability and surface integrity of Mg-Zn-Ca alloy, and to ensure the effective and efficient drilling for various applications in the medical and engineering fields. The present experimental study emphasizes the influence of Ca content, biofriendly coolants and their combined effect with standard drill bits on the surface quality and axial thrust force in the drilling operation of Mg-Zn-Ca alloy. The drilling parameters such as cutting speed, feed rate, standard tools, bio-compatible coolants were optimized with respect to the amount of Ca in the Mg-Zn alloy. The axial thrust force and average surface roughness of drilled holes were considered as response of the experiments. The drilled surfaces were measured for average surface roughness in the transverse direction along the centre path of the drilled hole and a qualitative analysis was also carried out using advanced confocal microscope. The results revealed that the cutting speed among continuous factors significantly influenced the axial thrust force and average surface roughness. The effect of categorical factors was assessed using a regression based ranking method. The results of statistical analysis revealed that high speed steel, and vegetable oil offered improved surface quality, whereas the coconut oil showed low axial thrust force. The liquid nitrogen showed high value of axial thrust force and average surface roughness due to the brittleness induced by cryogenic coolant before drilling operation.

•Binder-free 0D NiCo2S4/2D rGO nanocomposite electrodes for high-performance supercapacitors.•Synergistic effect of NiCo2S4/rGO delivers specific capacitance of 1202.57 F/g.•Symmetric device of the NCS-rGO(2:1) electrodes delivers high specific capacitance of 310.45 F/g.•Significant capacitance retention of ∼145% after 1000 cycles for symmetric device.•Asymmetric device of rGO||2:1 delivered energy and power densities of 70.9 Wh/kg and 163.6 kW/kg.

Platinum (Pt) and palladium (Pd) -based catalysts have sparked intense research interest for many important reactions in green energy and sustainable technologies such as key industrial petrochemical processes, fine chemical synthesis, environmental protection, renewable energy conversion and microbial, as their specific activity, stability and selectivity are greatly higher. However, the availability of low-cost electrodes/catalysts with high activity and stable electrochemical performance is crucial for the development of long-term and cost-effective green energy, environmental and sustainable technologies. In response to the growing demand for these products, the development of strategies to produce various materials is being intensified. This review summarizes the recent research efforts to develop advanced noble metal-based electrocatalysts with excellent performance for water splitting catalysis, CO2reduction, electrochemical sensors and antimicrobial applications. Pt and Pd co-catalysts in photocatalytic water splitting are examined for their contributions to clean hydrogen production, with a focus on bandgap adjustment, reduced recombination time, and enhanced charge carrier separation. The electrochemical reduction of carbon dioxide is also explored, highlighting the selectivity and efficiency of Pt and Pd systems, addressing both carbon capture and the generation of valuable chemicals. Similarly, their role as co-catalysts in photocatalytic carbon dioxide reduction is discussed for improved efficiency and selectivity. The review also addresses Pt- and Pd-based electrochemical sensors, emphasizing their catalytic roles in medical diagnostics and gas sensing. Further, the antimicrobial properties of Pt and Pd nanoparticles are explored, showcasing their potent inhibition of bacterial growth, disruption of biofilm formation, and effectiveness against multidrug-resistant bacteria. Additionally, the unique attributes of metal nanoclusters for biomedical sensing and imaging applications are discussed. Finally, a personal outlook is given to highlight the challenges and opportunities for the development of novel electrocatalysts suitable for a wide range of commercial applications in fostering advancements in sustainable technologies and materials.

•Fiber with particulates in epoxy has remarkable resistance to microbial growth.•Composite showed improvements in mechanical behaviours, suitable for structural applications.•Impact tests show a high capacity for energy absorption of 0.019 J/mm2.•The finding encourages polymer composites for a range of applications in multiple sectors.•This work highlights environmentally friendly, as well as antimicrobials effective materials.