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This long-term field trial aimed at remediating a Cu-contaminated soil to promote crop production and soil functions at a former wood preservation site. Twenty-eight field plots with total topsoil Cu in the 198-1,169 mg kg −1 range were assessed. Twenty-four plots (OMDL) were amended in 2008 with a compost (made of pine bark chips and poultry manure, OM, 5% w/w) and dolomitic limestone (DL, 0.2%), and thereafter annually phytomanaged with a sunflower-tobacco crop rotation. In 2013, one untreated plot (UNT) was amended with a green waste compost (GW, 5%) whereas 12 former OMDL plots received a second compost dressing using this green waste compost (OM2DL, 5%). In 2011, one plot was amended with the Carmeuse basic slag (CAR, 1%) and another plot with a P-spiked Linz-Donawitz basic slag (PLD, 1%). Thus six soil treatments, i.e., UNT, OMDL, OM2DL, GW, CAR, and PLD, were cultivated in 2016 with sunflower (Helianthus annuus L. cv Ethic). Shoots were harvested and their ionome analyzed. At high soil Cu contamination, the 1M NH 4 NO 3-extractable vs. total soil Cu ratio ranked in decreasing order: Unt (2.35) > CAR (1.02), PLD (0.83) > GW (0.58), OMDL (0.44), OM2DL (0.37), indicating a lower Cu extractability in the compost-amended plots. All amendments improved the soil nutrient status and the soil pH, which was slightly acidic in the UNT soil. Total organic C and N and extractable P contents peaked in the OM2DL soils. Both OMDL and OM2DL treatments led to higher shoot DW yields and Cu removals than the GW, CAR, and PLD treatments. Shoot DW yields decreased as total topsoil Cu rose in the OMDL plots, on the contrary to the OM2DL plots, demonstrating the benefits to repeat compost application after 5 years. Shoot Cu concentrations notably of OMDL and OM2DL plants fitted into their common range and can be used by biomass Mench et al. Phytomanagement of Cu-Contaminated Soils processing technologies and oilseeds as well. In overall, there is a net gain in soil physico-chemical properties and underlying soil functions. HIGHLIGHTS-Compost incorporated into Cu-contaminated soils improves the sunflower growth.-Soil organic matter increases in compost-amended soils.-Extractable soil Cu decreases in compost-amended soils.-Shoot Cu removal by sunflower reaches 26-88 g Cu ha −1 year −1 .

Doping material with nanoparticles is increasingly used as an effective method for improving their mechanical, optical, and sturdiness properties in many fields. More specifically, effective material development will depend on our ability to control nanoparticles’ shape, composition, and size. While crystalline nanophase can be examined easily, characterization of amorphous nanoparticles remains a challenge. Here, we investigate the chemical composition of sub-20-nm oxide nanoparticles grown in rare-earth doped silicate glass through the phase separation mechanism occurring under heat treatment. Using a combination of analytical techniques, we demonstrate that nanoparticle composition and, therefore, the chemical environment of encapsulated rare-earth ions, is nanoparticle size dependent. This new experimental evidence of composition change contributes unique insights on the phase separation mechanism that will lead to better comprehension and will guide development of future materials.

Purpose: Several preclinical studies have reported the presence of gadolinium (Gd) in different chemical forms in the brain, depending on the class (macrocyclic versus linear) of Gd-based contrast agent (GBCA) administered. The aim of this study was to identify, with a special focus on insoluble species, the speciation of Gd retained in the deep cerebellar nuclei (DCN) of rats administered repeatedly with gadoterate or gadodiamide 4 months after the last injection. Methods: Three groups (N = 6/group) of healthy female Sprague-Dawley rats (SPF/OFA rats; Charles River, L'Arbresle, France) received a cumulated dose of 50 mmol/kg (4 daily intravenous administrations of 2.5 mmol/kg, for 5 weeks, corresponding to 80-fold the usual clinical dose if adjusted for man) of gadoterate meglumine (macrocyclic) or gadodiamide (linear) or isotonic saline for the control group (4 daily intravenous administrations of 5 mL/kg, for 5 weeks). The animals were sacrificed 4 months after the last injection. Deep cerebellar nuclei were dissected and stored at −80°C before sample preparation. To provide enough tissue for sample preparation and further analysis using multiple techniques, DCN from each group of 6 rats were pooled. Gadolinium species were extracted in 2 consecutive steps with water and urea solution. The total Gd concentrations were determined by inductively coupled plasma mass spectrometry (ICP-MS). Soluble Gd species were analyzed by size-exclusion chromatography coupled to ICP-MS. The insoluble Gd species were analyzed by single-particle (SP) ICP-MS, nanoscale secondary ion mass spectroscopy (NanoSIMS), and scanning transmission electron microscopy with energy-dispersive X-ray spectroscopy (STEM-EDX) for elemental detection. Results: The Gd concentrations in pooled DCN from animals treated with gadoterate or gadodiamide were 0.25 and 24.3 nmol/g, respectively. For gadoterate, the highest amount of Gd was found in the water-soluble fractions. It was present exclusively as low-molecular-weight compounds, most likely as the intact GBCA form. In the case of gadodiamide, the water-soluble fraction of DCN was composed of high-molecular-weight Gd species of approximately 440 kDa and contained only a tiny amount (less than 1%) of intact gadodiamide. Furthermore, the column recovery calculated for this fraction was incomplete, which suggested presence of labile complexes of dissociated Gd 3+ with endogenous molecules. The highest amount of Gd was detected in the insoluble residue, which was demonstrated, by SP-ICP-MS, to be a particulate form of Gd. Two imaging techniques (NanoSIMS and STEM-EDX) allowed further characterization of these insoluble Gd species. Amorphous, spheroid structures of approximately 100-200 nm of sea urchin-like shape were detected. Furthermore, Gd was consistently colocalized with calcium, oxygen, and phosphorous, strongly suggesting the presence of structures composed of mixed Gd/Ca phosphates. No or occasional colocalization with iron and sulfur was observed. Conclusion: A dedicated analytical workflow pr...

DOI: 10.1002/9783527694907.ch4International audienceThis chapter presents four complementary element-specific bioimaging techniques: laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), nano secondary ion mass spectrometry (NanoSIMS), transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy (TEM/X-EDS), and synchrotron-based X-ray fluorescence (SXRF). LA-ICP-MS is a spatially resolved analytical technique mainly measuring metallic elements in solidmaterials. LA-ICP-MS bioimaging analysis has been applied to cancer studies to investigate metal-ion distribution changes in diseased versus healthy tissues. SIMS is an analytical technique that relies on the sputtering of ions from a solid surface by focused positive or negative primary ion beams and the subsequent analysis of the produced secondary ions by a mass spectrometer under high vacuum. NanoSIMS and TEM/X-EDS are operated under high vacuum where the sample is exposed to a high-energy ion beam or electron beam. These facts demand specific sample preparation strategies for biological samples, which are similar for both techniques and can be regarded together

Abstract:The political transformation of the Central Asian region has induced the implosion of the interconnected physical hydraulic infrastructure and its institutional management system. Land-locked Central Asian countries, with their climatic conditions and transboundary water resources, have been striving to meet their food security, to increase agricultural production, to sustain energy sectors, and to protect the environment. The existing water reservoirs are strategic infrastructures for irrigation and hydropower generation. Upstream countries (Tajikistan and Kyrgyzstan) favor the reservoirs' operation for energy supply, while downstream countries (Uzbekistan, Turkmenistan and Kazakhstan) push for irrigation use. This paper provides an overview of the current challenges and perspectives (technical, institutional, and legal regulations) and presents recommendations for the sustainable management of man-made water reservoirs in Uzbekistan.

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