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Zinc (Zn) is a crucial micronutrient essential for the growth and development of crops. Recently, there has been growing interest in harnessing its benefits through the application of zinc oxide (ZnO) nanoparticles (NPs) as an alternative to conventional fertilizers. Different types of ZnO NPs were synthesized in the laboratory by a co-precipitation method using different precursor metal (Zn(NO3)2 for ZnO-1 and ZnSO4 for ZnO-2) and sources of hydroxyl groups (NaOH for ZnO-1 and NH4OH for ZnO-2) or by a sol–gel method, using ZnC4H6O4 (ZnO-3) or ZnSO4 (ZnO-4) as precursor metal. This study focused on the effect of these Zn sources on the impact on lettuce (Lactuca sativa L.) cultivation under acidic and Zn-deficient soil conditions. The efficacy of these Zn sources was evaluated by measuring the lettuce fresh weight, the stem diameter, the Zn concentrations in young leaves and mature leaves, the photosynthetic pigment content (chlorophyll and carotenoid), and the overall Zn status in the soil and soil pore water. The ZnO NPs with particle sizes of 76–104 nm positively affected the stem thickness (with an increase of up to 1.4 times that of the control) and crop biofortification with Zn (up to 3.2 and 12.6 times the Zn in young leaf and mature leaf, compared to the control). The smaller ZnO NPs (ZnO-1 and ZnO-3) showed the highest concentrations of bioavailable Zn and Zn in pore water at the end of the cultivation period (with an average increase of 41% compared to larger sources), resulting in high biofortification levels in both mature and young leaves. Peak concentrations of dissolved Zn in soil pore water were observed at 18 days after planting, followed by a decline attributed to the retention of Zn in more insoluble forms in the soil. The difference in Zn concentration between mature leaves and young leaves indicated its limited mobility in the plant, with more Zn accumulating in mature leaves. [ABSTRACT FROM AUTHOR]

The micronutrient Zinc (Zn) is essential for the proper growth and development of crops. Zinc oxide nanoparticles (NPs) and fine particles are presented as an emerging alternative to more traditional fertilizers. In this study, the possible toxic effect of four laboratory-synthesized ZnO NPs and fine particles with different characteristics on tomato seed germination and vigor parameters was examined in comparison to bulk ZnO. Different metal precursors were used for the chemical synthesis of the particles: Zn(NO3)2 and ZnSO4, for particles named NIT-. and SUL-., respectively. In addition, the synthesis process was modified to obtain coated particles (denoted as UW-, NIT-UW and SUL-UW) and washed particles (denoted as W-, NIT-W and SUL-W). These particles were applied at different toxic doses (0, 1.4, 2.8, 5.6 and 11.2 g L−1). The results indicated that although the constant contact time between the ZnO particles did not affect the germination capacity of the seeds, it affected the growth of roots and hypocotyls, with a higher impact on the roots' development. This toxicity was more evident from the lowest particle dose used, although it did not prevent radicle and hypocotyl elongation during the development period studied (14 days). The synthesized coated particles (NIT-UW, SUL-UW) generated high toxicity on radicle and hypocotyl development, and this effect was observed from the first days of contact with the particles. The observed toxic effects on radicle length were minimized by the application of bulk ZnO particles. In the case of hypocotyl growth, these minor toxic effects were observed by using NIT-W particles and bulk ZnO. The possibility of positive effects on seed germination and development (radicle and hypocotyl length) when in continuous contact with ZnO, whether in fine particles, nanoparticles, or bulk sizes, was excluded. Furthermore, no benefits on germination parameters were observed by suppressing the final washing step in the particle's synthesis process, suggesting that particle coating did not provide any advantage for seed germination under these continuous contact conditions. [ABSTRACT FROM AUTHOR]

Fe and Mn (hydr)oxides are widely used as contaminant sorbents in water/wastewater systems but their potential use as micronutrient fertilizers is still poorly known. In this research, four nano-metal (hydr)oxides (amorphous Mn oxide (AMO), Fe-Mn binary oxide (FMBO), two-line ferrihydrite (2L-Fh) and goethite) were successfully synthesized and completely characterized (infrared and Mössbauer spectroscopy, X-ray diffraction particle size, specific surface area, point of zero charge). AMO, FMBO and 2L-Fh were introduced to interact with AgNO3 (20.0 µM) and TlNO3 (100.0 µM) diluted solutions for three days to check their potential capability as potential Ag+ and Tl+ adsorbents. AMO and FMBO (4% w/w) were tested as nanofertilizers by arranging a hydroponic bioassay for 35 days on white lupin culture as a Mn-hyperaccumulator plant model. AMO structure was identified as an amorphous mixture of Mn oxides while FMBO was an Fe dopped birnessite. Both materials were efficient in extracting Ag+ and Tl+ although large Mn concentration was released from FMBO to the solutions. AMO and FMBO promoted Fe and Mn nutrition in plants. Synthetic iron chelate (Fe-EDDHA), present in the nutrient dissolution, could be adsorbed onto AMO surface by producing Fe and Mn accumulation in roots and increasing Mn uptake rate without toxicity symptoms. Therefore, AMO and FMBO not only demonstrated their efficiency as adsorbents, but also displayed they would be promising nanomaterials as micronutrient fertilizers. [ABSTRACT FROM AUTHOR]

Diagnostic imaging is crucial to the diagnosis and monitoring of spondyloarthropathies. Magnetic resonance imaging is the most relevant tool for the early detection of sacroiliitis, allowing the institution of therapeutic strategies to impede the progression of the disease. This study illustrates the major criteria for a magnetic resonance imaging-based diagnosis of spondyloarthropathy. The cases selected here present images obtained from the medical records of patients diagnosed with sacroiliitis over a two-year period at our facility, depicting the active and chronic, irreversible forms of the disease. Although computed tomography and conventional radiography can also identify structural changes, such as subchondral sclerosis, erosions, fat deposits, and ankylosis, only magnetic resonance imaging can reveal active inflammatory lesions, such as bone edema, osteitis, synovitis, enthesitis, and capsulitis.