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This study examines the potential of iron nanoparticle-coated copper oxychloride in mitigating its toxic effects on earthworms, a key component of sustainable agriculture due to their role in enhancing soil quality and promoting plant growth. While earthworms and their coelomic fluid play a crucial role in enhancing soil health and promoting plant growth. Copper oxychloride, a commonly used fungicide, induces oxidative stress by disrupting antioxidant defense mechanisms in living systems. Through probit analysis, the median lethal concentration (LC50) of copper oxychloride was determined to be 2511.9 mg/kg. Artificial soil was treated with copper oxychloride at 60% and 80% of LC50, but the addition of iron nanoparticle-coated fungicide successfully reduced earthworm mortality to 0%. These findings offer promising insights into protecting non-target organisms from fungicide toxicity while maintaining agricultural productivity. The findings present a potential breakthrough in sustainable agriculture by demonstrating how nanotechnology can mitigate the harmful effects of fungicides on essential soil fauna. The use of iron nanoparticle-coated fungicides not only protects earthworms but also offers a path to maintaining ecological balance and enhancing crop productivity without compromising soil health., (© 2024. The Author(s).)

Reducing defects boosts room-temperature performance of a thermoelectric device.

UV radiation-induced DNA damages have adverse effects on genome integrity and cellular function. The most prevalent UV-induced DNA lesion is the cyclobutane pyrimidine dimer (CPD), which can cause skin disorders and cancers in humans. Rad4/XPC is a damage sensing protein that recognizes and repairs CPD lesions with high fidelity. However, the molecular mechanism of how Rad4/XPC interrogates CPD lesions remains elusive. Emerging viewpoints indicate that the association of Rad4/XPC with DNA, the insertion of a lesion-sensing β-hairpin of Rad4/XPC into the lesion site and the flipping of CPD's partner bases (5'-dA and 3'-dA) are essential for damage recognition. Characterizing these slow events is challenging due to their infrequent occurrence on molecular time scales. Herein, we have used enhanced sampling and molecular dynamics simulations to investigate the mechanism and energetics of lesion recognition by Rad4/XPC, considering multiple plausible pathways between the crystal structure of the Rad4-DNA complex and nine intermediate states. Our results shed light on the most likely sequence of events, their potential coupling and energetics. Upon association, Rad4 and DNA form an encounter complex in which CPD and its partner bases remain in the duplex and the BHD3 β-hairpin is yet to be inserted into the lesion site. Subsequently, sequential base flipping occurs, with the flipping of the 5'-dA base preceding that of the 3'-dA base, followed by the insertion of the BHD3 β-hairpin into the lesion site. The results presented here have significant implications for understanding the molecular basis of UV-related skin disorders and cancers and for paving the way for novel therapeutic strategies., (© The Author(s) 2023. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Recently, superionic thermoelectrics have attracted enormous attention due to their ultralow thermal conductivity and high figure-of-merit (zT). However, their high zT is generally obtained deep inside the superionic phase, e.g., near 1000 K in Cu 2 X (X: chalcogen atom) family despite a relatively low superionic transition temperature of ∼400 K. At such high temperatures, the liquid-like flow of the metal ions results in material's degradation. Here, we present thermoelectric properties of superionic Ag 2 Te synthesized by various methods. The sintered Ag 2 Te samples are shown to exhibit an unpredictable behavior with respect to the sign of thermopower (S) in the superionic phase and the magnitude of electrical conductivity (σ). We overcome this issue using an all-room-temperature fabrication technique leading to an excellent reproducibility from one sample to another. To improve the zT of Ag 2 Te beyond the phonon-liquid electron-crystal limit (∼0.64 at 575 K in the ingot samples), we adopted a heirarchical nanostructuring technique, which effectively suppressed the thermal conductivity, leading to a significant improvement in the zT values for both n-type and p-type samples. We obtained zT of 1.2 in the n-type and 0.64 in the p-type Ag 2 Te at 570 K. These values supersede the zT of any Ag 2 Te previously reported. At 570 K, for our ball-milled/cold-pressed samples, the critical current density for metal-ion migration exceeds 15 A cm -2 , which further confirms that Ag 2 Te is a promising thermoelectric material. Our results are supported by first-principles density functional theory calculations of the electronic and thermal properties.

The semiconductor Cu 2 ZnSnSe 4 (CZTSe) is a promising candidate for both thermoelectric and photovoltaic energy harvesting applications due to a combination of features such as direct band gap, high absorption coefficient, and low thermal conductivity. We report the solid-state synthesis and characterization of Mn-doped Cu 2 Zn 1- x Mn x SnSe 4 ( x = 0, 0.05, 0.10, and 0.15) in an attempt to explore the effect of isovalent substitution at the Zn site. X-ray diffraction and Raman spectroscopy of all specimens confirmed the formation of a single-phase tetragonal kesterite structure (space group I 4̅). The band gap obtained by UV-visible diffuse reflectance measurements was 1.42 eV for all compositions. Thermoelectric properties were measured in the range 300-785 K. Electrical resistivity was metallic and reduced on Mn doping, while the Seebeck coefficient exhibited a p-type semiconducting behavior that enhanced on Mn doping, with associated enhancement of the power factor. Lattice thermal conductivity showed a 1/ T behavior, falling from about 1.9-2.7 W m -1 K -1 at 300 K to 0.51-0.9 W m -1 K -1 above 750 K. The combined effect of enhanced power factor and reduced lattice thermal conductivity resulted in a figure of merit ZT in the range of 0.19-0.42 above 750 K. Thin-film photovoltaic devices with a CZTSe absorber and an SnSe electron transport layer gave 3.2% efficiency.

Interleukin-4 (IL-4) is a multifunctional cytokine that plays a critical role in apoptosis, differentiation and proliferation. The intensity of IL4 response depends upon binding to its receptor, IL-4R. The therapeutic efficiency of interleukins can be increased by generating structural mutants having greater stability. In the present work, attempts were made to increase the stability of human IL-4 using in-silico site directed mutagenesis. Different orthologous sequences of IL4 from Pan troglodytes , Aotusnigriceps , Macacamulatta , Papiohamadryas , Chlorocebusaethiops , Vicugnapacos , Susscrofa and Homo sapiens were aligned using Clustal Omega that revealed the conserved and non-conserved positions. For each non-conserved position, possible favorable and stabilizing mutations were found using CUPSAT with predicted ΔΔG (kcal/mol). The one with highest ΔΔG (kcal/mol) among all possible mutations, for each non-conserved position was selected and introduced manually in human IL-4 sequence resulting in multiple mutants of IL-4. Mutant proteins were modeled using structure of IL4 (PDB ID: 2B8U) as a template by SWISS MODEL. The mutants A49L and Q106T were identified to have stability centre using SCide. Molecular dynamics and docking analysis also confirmed the mutants stability and binding respectively. Mutants A49L and Q106T had -7.580079 kcal/mol and -39.418124 kcal/mol respectively lesser energy value than the wild type IL4. The result suggested that, the stability of human IL-4 has been increased by mutation.