Dhemaji College

There is a consistent increase in persistent organic pollutants and co-contaminants across diverse ecosystems. The polychlorinated biphenyls, polycyclic aromatic hydrocarbons and organochlorine pesticides along with heavy metals pose serious threats to our ecosystem and environment. Use of conventional physical and chemical decontamination technologies of persistent organic pollutant removal is often discouraged due to their operational complexities and potential environmental hazards. The pollutant removing potential of certain plants has been attributed to the assemblance of putative microbial populations residing in their inner tissues, popularly known as the endophytes. The current review addresses the potential of endophyte microbial mutualists as significant contributors in phytoremediation. The intrinsic metabolic machineries of the endophytic fungal cell factories accelerate the host plant’s mechanism in pollutant decontamination. Notwithstanding significant progress in the field, a comprehensive understanding of host-endophyte interaction during pollutant removal is still challenging. In this context, the current review has been designed to study the mechanistic interactions of endophyte fungi-mediated phytoremediation of persistent organic pollutants and co-contaminants. The review delineates the characteristics of various persistent organic pollutants, provides a concise overview of endophytic and arbuscular mycorrhizal fungi, and elucidates their essential mechanisms in augmenting the phytoremediation of persistent organic pollutants and associated contaminants. The recent update discusses technological interventions in host-fungal endophyte interactions that enhance phytoremediation efficiency and highlights potential in future research approaches.

With the growing demand for compact, high-performance and reconfigurable antenna systems in mid-band 5G communication (3.3–6 GHz), polarization agility has become essential for improving link reliability and spectral efficiency. This paper presents the design, simulation and experimental validation of a polarization reconfigurable microstrip patch antenna capable of dynamically switching between vertical (VP) and horizontal (HP) linear polarization states using a single RF excitation port. The antenna employs two orthogonal microstrip feedlines connected via PIN diode switches to a common feed, enabling selective excitation of adjacent patch edges. This facilitates activation of the fundamental TM01​ or TM10​ mode, producing vertical or horizontal polarization, respectively. Fabricated on an FR4 substrate, the antenna features a low-profile, planar configuration ideal for compact RF systems. Simulated and measured resonances occur at 5.31/5.40 GHz (VP) and 5.27/5.33 GHz (HP), respectively. The antenna achieves –10 dB impedance bandwidths of 3.52% (VP) and 6.01% (HP), peak gains of 2.48 dBi and 2.76 dBi and axial ratios above 48 dB, confirming high polarization purity and low cross-polarization. Radiation patterns show good agreement with simulations. The proposed design offers a compact and efficient solution for applications demanding polarization reconfigurability, making it well-suited for advanced wireless communication systems.

The increasing global demand for maintaining sustainable agriculture has focused on the critical role played by endophytic entomopathogenic fungi as dual-purpose microbial agents facilitating plant growth promotion and pest management. Endophytic entomopathogenic fungi as natural endosymbionts, provide multifaceted benefits, such as improving plant growth and nutrient uptake, enhancing tolerance to biotic and abiotic stresses, and protecting the crops against devastating insect pests, pathogens, nematodes, and weeds. Addressing the potential of endophytic entomopathogenic fungi in agriculture has eventually reduced the dependence on toxic agrochemicals, thereby assists to adopt key alarms of environmental safety and agricultural sustainability. Direct application of this category of fungi involves seed treatment, soil inoculation, and foliar sprays, resulting enhancement in plant endosphere colonization, assisting in optimum plant protection and growth promotion. Indirect applications include the potential use of bioformulations, thereby reducing the reliance on toxic chemical fertilizers and pesticides. Customized strategies for integrating entomopathogenic fungi into sustainable pest and disease management frameworks must be generated to boost their use efficiency under field evaluations. These strategies must ensure that the fungi are compatible with other biocontrol agents and recommended dosages of agrochemicals. The integration of advanced technologies, including the genetic engineering, myconanoformulations, artificial intelligence, and the internet of things, alongside Fuzzy logics, has recently revolutionized the strategic advancements in entomopathogenic research for sustainable plant growth promotion and crop protection, leading to the development of climate-smart agriculture.

Abstract This work explores the design, synthesis, and analytical investigations of novel fluorogenic chemosensors based on the 1,2,3-triazole moiety engineered to respond selectively to fluoride and cyanide anions. The rationale for selecting the triazole-based receptor lies on the ability of 1,2,3-triazoles to recognize anions through their polarized Csp2−H proton, together with an ortho-substituted phenolic-OH group through a cooperative mechanism. The ortho-substituted phenolic-OH provides receptor preorganization as well as an acidic hydrogen, facilitating analyte-induced deprotonation by a basic anion. The resulting phenoxide is stabilized by conjugative delocalization, producing a pronounced UV−visible response toward F− and CN−. The sensing behavior has been evaluated in DMSO using both UV−visible absorption and fluorescence emission spectroscopy. The appearance of a new absorption peak along with the original absorption peak of the sensor as well as quenching of the emission peak upon addition of the analyte to the sensor significantly implies successful recognition. Key performance metrics, such as binding affinities of 4.09 × 103 M−1 for CN− with phenyl 2-((1-(2-hydroxyphenyl)-1H-1,2,3-triazol-4-yl)methoxy)benzoate (3aa), stoichiometric ratios, as well as detection limits of 17.2 μM for CN− with 3aa have been evaluated with the help of UV−visible absorption spectroscopy and have been performed for all the receptor molecules. To demonstrate practical utility, the chemosensor was successfully employed to detect cyanide in sprouted potatoes quantitatively. Further, a DFT study has also been conducted which successfully validates the proposed sensing mechanism.