Highly efficient Co3O4/GO adsorbent recycled from spent Lithium-Ion Batteries toward cationic dye from aqueous solutions

Eusociality is exceptionally rare in mammals, and its proximate mechanisms remain poorly understood. Naked mole-rats provide a striking example, with reproduction restricted to a single queen, while all other females remain infertile¹. Here we identify a chemical signal in queens that can regulate this reproductive hierarchy. Isopropyl myristate is a low-volatility ester that is enriched in queens and nearly absent from non-breeding animals. Isopropyl myristate is detected by peripheral and central olfactory neurons and elicits avoidance in high-ranking animals. Exposure alters levels of prolactin and progesterone in non-breeders to suppress reproduction. Daily addition of isopropyl myristate to a queenless colony prevented queen succession, whereas withdrawal triggered aggression and reproductive competition. Isopropyl myristate was also detected in breeding females of several Fukomys mole-rat species, but reaches higher levels in naked mole-rats, paralleling their extreme reproductive skew. These findings reveal a chemical cue that can mediate reproductive suppression in a mammal, linking insect and mammalian eusociality.

Background

The expansive usage of metal oxide nanoparticles (NPs) as a potential constituent in modern nano-enabled products raises threats to environmental safety and crop production. Key lime is an economic plant enriched with secondary metabolites and imperative bioactive compounds. NPs can alter lime’s essential components, making it an ideal model for monitoring NPs’ toxicity. Hence, a comparative analysis of two synthesized metallic NPs, aluminum (Al2O3) and copper (CuO) at concentrations of 0, 100, 200, and 500 mg/L, was conducted to assess their impact on the growth and quality attributes of lime plants under controlled micro-conditions.

Results

Observations from germination, growth, physiological, biochemical, and ionomic attributes showed that Al2O3-NPs had variable effects in a concentration-dependent manner, while CuO-NPs were toxic at all concentrations. Heatmap and principal component analysis revealed that CuO-NPs instigated more pronounced toxic effects compared with Al2O3-NPs at each applied concentration, as evidenced by heightened oxidative stress symptoms. CuO-NPs exerted their toxicity by over-accumulating reactive oxygen radicals and methylglyoxal and elevating lipoxygenase activity, causing peroxidation of membrane lipids and attenuation of photosynthetic pigments. Al2O3-NPs-treated plants relatively up-regulated the pool of phenolics, flavonoids, anthocyanins, ascorbic acid, and α-tocopherol as well as stimulated the activity of enzymatic antioxidants. Ionomics analysis showed excessive copper accumulation in toxic levels (~ 15-fold), which triggered nutritional imbalance (Mg, Si, P, S, Cl, K, Ca, Fe, Cu, and Zn) and disruption of chelating molecules, nitric oxide, and hydrogen sulfide.

Conclusions

This work provides precious insights into the differential impacts of metallic NPs on the development and quality of lime plants and the underlying mechanisms involved in NPs accumulation, highlighting the possible hazards of manufactured NPs in the environment, especially for valuable plant species. However, the controlled use of NPs—particularly aluminum oxide—may offer agronomic benefits, but their application must be carefully handled to prevent toxicity.

Aluminum (Al) toxicity exhibits a challenge for growing strawberries (Fragaria x ananassa Duch), impacting their growth and nutritional value. Considerably in this study, we explored how melatonin, an endogenous plant hormone, can help alleviate Al stress in strawberry plants. The current research examined the effects of foliar spraying melatonin (0,50, and 100 ppm) on growth indicators, photosynthetic pigment levels, carbon and nitrogen assimilation, oxidative stress markers, and fruit quality attributes under Al stress (100 µM) in a controlled pot experiment conducted in a greenhouse. The results revealed that exposure to Al stress significantly reduced the adequate growth, as well as the yield and quality of fruits. Melatonin application improved plant growth parameters, especially at a concentration of 100 ppm, enhancing the levels of photosynthetic pigments and boosting carbohydrate and nitrogen metabolism. Moreover, melatonin played a role in reducing stress markers while increasing enzymatic antioxidant activities (catalase, superoxide dismutase, ascorbate peroxidase, glutathione peroxide, glutathione-S-transferase, and phenylalanine ammonia-lyase) and secondary metabolites (proline, ascorbic acid, flavonoids, reduced glutathione, and phytochelatins), while decreasing polyphenol oxidase activity as well as phenolics content, implying a role in ROS scavenging. The results underscore the promise of melatonin as a method to enhance the ability of strawberries to withstand Al toxicity and promote friendly agricultural practices in polluted soils.

Abstract: A general procedure was developed to synthesize and characterize some new 1,2,4-triazole, 3-cyanopyridine, 3-aminothienoquinoline and 5,6,7,8-tetrahydroisoquinoline derivatives bearing a 4-aminosalicylic acid ester moiety as substructure. Some of them were further modified to give new derivatives. This work allowed the preparation of 18 new compounds obtained in good yields and under simple experimental conditions. These compounds were evaluated for their antimicrobial activity against four strains of bacteria and two fungal species.