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Lanthanum (La), the second most abundant rare earth element (REE) is emerging as an environmental issue, with the potential to impact ecosystems and human health. Major sources of soil contamination by La include agricultural, and industrial activities. Lanthanum is non-essential for plant growth but accumulates in various plant parts. The uptake of La by plants is intricately influenced by various factors such as soil pH, redox potential, cation exchange capacity, presence of organic acids and rhizosphere composition. These factors significantly impact the availability and absorption of La ions. Lanthanum impact on plants depends on soil characteristics, cultivated species, developmental stage, La concentration, treatment period, and growth conditions. Excessive La concentrations affect cell division, DNA structure, nutrient uptake, and photosynthesis and induce toxicity symptoms. Plants employ detoxification mechanisms like vacuolar sequestration, osmolyte synthesis, and antioxidant defense system. However, higher concentrations of La can overwhelm these defense mechanisms, leading to adverse effects on plant growth and development. Further, accumulation of La in plants increases the risk for human exposure. Strategies to mitigate La toxicity are, therefore, vital for ecosystem protection. The application of phytoremediation, supplementation, chelation, amendments, and biosorption techniques contributes to the mitigation of La toxicity. This review provides insights into La sources, uptake, toxicity, and alleviation strategies in plants. Identifying research gaps and discussing advancements aims to foster a holistic understanding and develop effective strategies for protecting plant health and ecosystem resilience against La contamination., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In the fast-evolving realm of communication technology, microstrip patch antennas (MPAs) are in high demand owing to their compact size, lightweight, inexpensive, ease of integration, and compatibility with modern electronic devices. This research focuses on the synthesis of ZnAl 2 O 4 Ca (ZAC) ceramic nanoparticles using an economical sol-gel method suitable for microstrip patch antenna applications. The structural analysis study of ZAC nanoparticles confirmed the polycrystalline nature with 8.1 nm of crystallite size whereas an investigation of functional groups showed the corresponding vibration modes. Morphological investigation revealed the spherical grains having their mean diameter of 12.32 nm. The dielectric property's examination, revealed the dielectric permittivity of 13, loss tangent of 0.02, and conductivity of 67 μΩ -1  cm -1 . Furthermore, a prototype patch antenna fabricated using ZAC ceramics demonstrated a dual-band performance at frequencies 2.8 GHz and 4.8 GHz, with return losses of - 25.78 dB and - 28.5 dB, respectively. This work suggests the suitability of ZAC ceramic nanoparticles for use in WLAN applications., (© 2024. The Author(s).)

Soil salinization significantly affects crop production by reducing crop quality and decreasing yields. Climate change can intensify salinity-related challenges, making the task of achieving global food security more complex. To address the problem of elevated salinity stress in crops, nanoparticles (NPs) have emerged as a promising solution. NPs, characterized by their small size and extensive surface area, exhibit remarkable functionality and reactivity. Various types of NPs, including metal and metal oxide NPs, carbon-based NPs, polymer-based NPs, and modified NPs, have displayed potential for mitigating salinity stress in plants. However, the effectiveness of NPs application in alleviating plant stress is dependent upon multiple factors, such as NPs size, exposure duration, plant species, particle composition, and prevailing environmental conditions. Moreover, alterations to NPs surfaces through functionalization and coating also play a role in influencing plant tolerance to salinity stress. NPs can influence cellular processes by impacting signal transduction and gene expression. They counteract reactive oxygen species (ROS), regulate the water balance, enhance photosynthesis and nutrient uptake and promote plant growth and yield. The objective of this review is to discuss the positive impacts of diverse NPs on alleviating salinity stress within plants. The intricate mechanisms through which NPs accomplish this mitigation are also discussed. Furthermore, this review addresses existing research gaps, recent breakthroughs, and prospective avenues for utilizing NPs to combat salinity stress., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Mine tailings are the discarded materials resulting from mining processes after minerals have been extracted. They consist of leftover mineral fragments, excavated land masses, and disrupted ecosystems. The uncontrolled handling or discharge of tailings from abandoned mine lands (AMLs) poses a threat to the surrounding environment. Numerous untreated mine tailings have been abandoned globally, necessitating immediate reclamation and restoration efforts. The limited feasibility of conventional reclamation methods, such as cost and acceptability, presents challenges in reclaiming tailings around AMLs. This study focuses on phytorestoration as a sustainable method for treating mine tailings. Phytorestoration utilizes existing native plants on the mine sites while applying advanced principles of environmental biotechnology. These approaches can remediate toxic elements and simultaneously improve soil quality. The current study provides a global overview of phytorestoration methods, emphasizing the specifics of mine tailings and the research on native plant species to enhance restoration ecosystem services., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Cadmium (Cd) is a highly toxic heavy metal that adversely affects humans, animals, and plants, even at low concentrations. It is widely distributed and has both natural and anthropogenic sources. Plants readily absorb and distribute Cd in different parts. It may subsequently enter the food chain posing a risk to human health as it is known to be carcinogenic. Cd has a long half-life, resulting in its persistence in plants and animals. Cd toxicity disrupts crucial physiological and biochemical processes in plants, including reactive oxygen species (ROS) homeostasis, enzyme activities, photosynthesis, and nutrient uptake, leading to stunted growth and reduced biomass. Although plants have developed defense mechanisms to mitigate these damages, they are often inadequate to combat high Cd concentrations, resulting in yield losses. Nanoparticles (NPs), typically smaller than 100 nm, possess unique properties such as a large surface area and small size, making them highly reactive compared to their larger counterparts. NPs from diverse sources have shown potential for various agricultural applications, including their use as fertilizers, pesticides, and stress alleviators. Recently, NPs have emerged as a promising strategy to mitigate heavy metal stress, including Cd toxicity. They offer advantages, such as efficient absorption by crop plants, the reduction of Cd uptake, and the enhancement of mineral nutrition, antioxidant defenses, photosynthetic parameters, anatomical structure, and agronomic traits in Cd-stressed plants. The complex interaction of NPs with calcium ions (Ca 2+ ), intracellular ROS, nitric oxide (NO), and phytohormones likely plays a significant role in alleviating Cd stress. This review aims to explore the positive impacts of diverse NPs in reducing Cd accumulation and toxicity while investigating their underlying mechanisms of action. Additionally, it discusses research gaps, recent advancements, and future prospects of utilizing NPs to alleviate Cd-induced stress, ultimately promoting improved plant growth and yield., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Miniaturization of microstrip patch antennas (MPAs) is vital in applications such as wireless networks, mobile devices, global positioning satellites, and upcoming wireless terminals. This miniaturization has led to a demand for new materials with higher permittivity compared to the existing ones. Zinc aluminate (ZnAl 2 O 4 ) ceramic is an exceptional and versatile material in this context, thanks to its high dielectric permittivity and low tangent loss, making it suitable for microwave applications. This article explores the feasibility of sol-gel-prepared Ca-doped ZnAl 2 O 4 ceramic nanoparticles to be useful in fabricating a MPA. These nanoparticles were examined using X-ray diffraction, which confirmed their polycrystalline structure, and the morphological investigation evidenced the spherical grains having a mean diameter of 16 nm. The dielectric permittivity of the ZnAl 2 O 4 Ca nanoparticles is 21.11, with a tangential loss of 0.0247. A prototype MPA made by using Ca-doped ZnAl 2 O 4 nanoparticles showed a return loss of -20.92 dB at a resonance frequency of 6.8 GHz with a bandwidth of 600 MHz. These results indicate that Ca-doped ZnAl 2 O 4 ceramic nanoparticles possess exceptional dielectric characteristics, which make them a promising candidate for MPA applications., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Methanol is noxious to insect pests, but most plants do not make enough of it to shield themselves from encroaching insects. Methanol emission is known to increase in the instance of herbivory. In the current study, we showed that Aspergillus niger pectin methylesterase over-expression increases methanol emission and confers resistance to polyphagous insect pests on transgenic cotton plants by impeding the possible methanol detoxification pathways. Transgenic plants emitted ∼11 fold higher methanol displaying insect mortality of 96% and 93% in Helicoverpa armigera and Spodoptera litura, respectively. The larvae were unable to survive and finish their life cycle and the surviving larvae exhibited severe growth retardation. Insects try to detoxify methanol via catalase, carboxylesterase and cytochrome P450 monooxygenase enzymes, amongst which cytochrome P450 plays a major role in oxidizing methanol to formaldehyde and formaldehyde to formic acid, which is broken down into carbon dioxide and water. In our study, catalase and esterase enzymes were found to be upregulated, but cytochrome P450 monooxygenase levels were not much affected. Leaf disc assays and In-planta bioassays also showed 50-60% population reduction in the sap sucking pests, such as Bemisia tabaci and Phenacoccus solenopsis. These findings imply that elevated methanol emissions confer resistance in plants against chewing and sap-sucking pests by tampering the methanol detoxification pathways. Such mechanism will be useful in imparting expansive resistance against pests in plants., Competing Interests: Declaration of Competing Interest Authors declare no conflict of interest with anyone., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Chromium (Cr), one of the hazardous pollutants, exists predominantly as Cr(VI) and Cr(III) in the environment. Cr(VI) is more toxic than Cr(III) due to its high mobility and solubility. Elevated levels of Cr in agricultural soil due to various anthropogenic activities cause Cr accumulation in plants, resulting in a significant reduction in plant yield and quality due to Cr-induced physiological, biochemical and molecular alterations. It can infiltrate the food chain through crop plants and cause harmful effects in humans via biomagnification. Cr(VI) is linked to cancer in humans. Therefore, mitigation strategies are required to remediate Cr-polluted soils and limit its accumulation in plants for safe food production. Recent research on metal and metal oxide nanoparticles (NPs) has shown that they can effectively reduce Cr accumulation and phytotoxicity. The effects of these NPs are influenced by their type and dose, exposure method, plant species and experimental settings. In this review, we present an up-to-date compilation and comprehensive analysis of the existing literature regarding the process of uptake and distribution of Cr and impact and potential mechanisms of metal and metal oxide nanoparticles led mitigation of Cr-induced stress in plants. We have also discussed recent developments, existing research gaps and future research directions in the field of Cr stress mitigation by NPs in plants. Overall, this review can provide valuable insights in reducing Cr accumulation and toxicity using metal and metal oxide nanoparticles, thereby promoting safe and sustainable cultivation of food and phytostabilization of Cr-polluted soil., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Cotton is a significant industrial crop, playing an essential role in the global economy that suffers several setbacks due to biotic and abiotic adversities. Despite such problems, biotechnological advances in cotton are limited because of genetic transformation and regeneration limitations. Here, we present a detailed protocol optimized based on previously published papers, along with our modifications. These involve changes in Agrobacterium concentration, co-cultivation time and temperature, hormones used for regeneration, media manipulation for embryogenic callus production, and efficient rescue of deformed embryos. Further, this protocol has been used in genetic studies on biotic and abiotic stress in cotton. This protocol assures a reproducible stable transgenic cotton development procedure via somatic embryogenesis that can be used by researchers worldwide. This protocol was validated in: Nat Biotechnol (2016), DOI: 10.1038/nbt.3665., Competing Interests: Competing interestsThe authors declare that there are no existing conflicts of interest as to their knowledge., (Copyright © 2023 The Authors; exclusive licensee Bio-protocol LLC.)

This paper reports the sol-gel preparation of ZnAl 2 O 4 (ZA) and ZnAl 2 O 4 -TiO 2 (ZAT) dielectric ceramic nanoparticles for fabricating prototype microstrip patch antennas. The prepared nanoparticles were polycrystalline in nature with their crystallite sizes of 9.4 and 11 nm, along with average grain diameters of 16 and 12 nm corresponding to samples ZA and ZAT. Dielectric properties were investigated using an LCR meter, which endorsed enhanced dielectric permittivity and decreased dielectric loss. Finally, prototype microstrip patch antennas named AZA and AZAT were fabricated using the prepared nanoparticles, and their performances were evaluated. Both antennas exhibited resonant peaks in the frequency range from 6.4 to 6.5 GHz. The antenna AZAT showed a return loss of -37.07 dB with a voltage standing wave ratio (VSWR) of 1.02 compared to the return loss of -19.42 dB, and a VSWR of 1.24 corresponds to AZA. The AZAT antenna's improved return loss can be regarded as the increased dielectric permittivity and reduced tangent loss of the ZAT sample. Furthermore, the ZAT antenna evidenced increased/decreased forwarded/reflected power decreased reflection coefficient and an optimal VSWR value compared to that of the AZA antenna., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Zinc aluminate (ZnAl 2 O 4 ) is a well-recognized ceramic demanded in several microwave applications. Further, the addition of dielectric materials in ZnAl 2 O 4 improved its dielectric properties, which is promising for the realization of a microstrip patch antenna. This article reports the investigation of ZnAl 2 O 4 TiO 2 (ZAT) dielectric ceramic nanoparticles synthesized by the sol-gel process. The X-ray diffraction analysis revealed the crystalline nature of the prepared nanoparticles, with a tetragonal structure of anatase-, and rutile-TiO 2 phases coexisting with the cubic phase of ZnAl 2 O 4 . The estimated crystallite size of the dielectric ceramic is 13.3 nm. Transmission electron microscopy (TEM) micrographs demonstrated the spherical grains with their mean diameter of 14.75 nm, whereas the selected-area electron diffraction (SAED) pattern endorsed the crystallinity of the sample. Raman measurement revealed the vibrational modes in accordance with the TiO 2 and ZnAl 2 O 4 compounds. The dielectric properties of the ZAT sample showed the dielectric permittivity in the range of 22.12-21.63, with its minimum loss from 0.056 to 0.041. Finally, a prototype microstrip antenna was fabricated using the prepared nanoparticles, which demonstrated a return loss of - 30.72 dB at the resonant frequency of 4.85 GHz with its bandwidth of 830 MHz., (© 2022. The Author(s).)