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Glaucoma is a multifactorial eye disease, characterized by progressive optic neurodegeneration. Elevation of the intraocular pressure is the main risk factor for glaucoma and is a consequence of an imbalance in the aqueous humor hydrodynamics, the physiology of which is influenced by the homeostatic equilibrium of essential elements, oxidative stress, and antioxidants. The aim of this work was to study local alterations in glaucomatous patients from two different, but connected, points of view: (i) the total antioxidant capacity (as an indicator of oxidative damage) and (ii) the concentration of mineral elements and their isotopic composition. Such objective was pursued using aqueous humor from patients diagnosed with pseudoexfoliation glaucoma (PEXG, n = 17) and primary open-angle glaucoma (POAG, n = 5) and age-matched control subjects (n = 16). The total antioxidant capacity (TAC) was examined in both aqueous humor and 60 serum samples (n = 20 controls, n = 20 for PEXG, and n = 20 for POAG), both showing higher TAC for the glaucoma population. The concentrations of the essential mineral elements (Cu, Fe, Mg, Na, P, and Zn) and the isotopic compositions of Cu and Zn were determined in aqueous humor using single-collector and multi-collector inductively coupled plasma–mass spectrometry, respectively. Significant differences were established for Mg and P levels when comparing the results for glaucomatous patients with those for the control population (p < 0.01 and p < 0.05 for Mg and P respectively, ANOVA and Kruskal-Wallis). The Zn isotopic composition was significantly shifted from that for the control population for PEXG patients. A significant difference in the isotopic composition of Zn was also established between the PEXG and POAG glaucoma cohorts.

Eye fluids (aqueous humour and vitreous humour) may be helpful in estimating ante-mortem blood levels, since some parameters measured in these fluids have proved to be stable or to change in a predictable way after death. This would help in diagnosing the cause of death in some diseases or to evaluate ante-mortem blood levels in certain animals not easy to handle or with difficult access. In order to establish reference values of some parameters in blood and eye fluids (aqueous humour and vitreous humour), as well as the possible correlation among these three different fluids, various minerals and electrolytes (Ca, P, Mg, K, Na, Fe, Cr, Co, Ni, Cu, Zn, Se and Mo) were measured in 15 four to five year-old Lidia bulls, all dying after a period of significant stress and major exertion. Plasmatic values of Mg and P were much greater than reported in the literature. In general, mineral plasmatic values were greater than those found in ocular fluids (aqueous and vitreous), while Na, K and Cr were similar in the three fluids. We have verified the existence of correlations in P, Co and Mo among the three fluids measured, and between Se of plasma and vitreous humour. But the most marked correlations were observed in Mo (plasma -aqueous humour, r = 0.893, plasma-vitreous humour, r = 0.945, HA -HV, r = 0.849), in P (plasma-vitreous humour, r = 0.726) and in Co (plasma-vitreous humour, r = 879).

Opacification of intraocular lenses (IOLs) due to the formation of calcium phosphate occurs because of their contact with the aqueous humor (AH), which is supersaturated with respect to calcium phosphate. Calcification of IOLs was simulated in vitro using a batch reactor in which the IOLs were exposed to solutions simulating AH. Based on the precise and reproducible measurement of the rates of formation of mineral deposits on the IOLs, it is possible to develop reliable screening tests of different types of IOL materials. Depending on their material composition, IOLs are expected to present different active sites for the growth of deposits. Measurements of the kinetics of formation of hydroxyapatite (Ca 5 (PO 4 ) 3 OH; HAP) were used to compare the relative tendency of IOL towards calcification. The trend the IOLs tested showed towards calcification was found to correlate with contact angle values. In the case of hydrophobic IOLs, the surface charge calculated from the corresponding zeta potential measurements was low in comparison with the respective high (absolute) values of the mineralizing hydrophilic IOLs, suggesting strong correlation between surface charge and tendency to calcify. The in vitro results align with the in vivo tests, suggesting that in vivo tests can be safely substituted or at least significantly reduced by the in vitro model. Graphical Abstract

Orientation: Even though there has been a phenomenal increase in the number of women employed in the mining industry, the figures hide many gender inequalities as the gendered impediments to career advancement persist despite South Africa’s remarkable equity policy regime. However, it is unclear, from the perspective of the women themselves, how their career advancement is encumbered. Research purpose: This study reflects on the prospects for career advancement by exploring the work and organisational experiences of women in core mining positions in an open-cast mining organisation in South Africa. Motivation for the study: To reflect on the prospects for career advancement of women in core mining positions. Research approach, design and method: Eight professional women, selected through a purposive sampling procedure, participated in in-depth unstructured interviews. Data were analysed using Creswell’s simplified version of the Stevick–Colaizzi–Keen method, guided by the lens of gendered organisations. Main findings: Three themes emerged: (1) male domination that has marginalised women and compelled them to emulate masculinity has legitimised existing gender barriers, (2) the long, awkward and unpredictable hours of work have deepened women’s time constraints because they have to combine the home or family caretaker role with work, and (3) the essence of being a woman in a mining organisation. Practical/managerial implications: The study may present South African managers with a better understanding of how work and organisational features, policies, daily practices and discourses impede career advancement of women in core mining positions. Organisations should train managers to create conditions that minimise barriers and maximise performance and advancement, and align retention strategies. Contribution/value-add: This study builds on existing knowledge about career advancement of women by providing new and valuable information specific to women in core mining positions in an open-cast mining organisation in South Africa, seen through the lens of gendered organisational theory. The findings highlight the need for organisational theory research that is responsive to the subtle issues and gendered assumptions that sustain encumbrances to women’s career trajectories.

Melting is an efficient method to turn municipal solid waste incineration (MSWI) fly ash (FA) into non-hazardous material. Coal fly ash (CFA) was selected as the silica-alumina source to carry out co-melting research with MSWI FA in this work. The effects of the temperature and the CFA content on mineral transformation and the migration characteristics of heavy metals were analyzed. The results showed that the mixtures of MSWI FA and CFA reacted at high temperatures to mainly generate Ca 2 Al 2 SiO 7 , Ca 2 SiO 4 , and CaAl 2 Si 2 O 8 primarily and then melted and formed the amorphous-phase vitreous body when the CFA content was more than 40% and the temperature was higher than 1300 °C. During the melting process, Cd and Pb were almost volatilized, while Cr, Mn, and Ni were almost retained. Besides, the volatilization rates of Cu and Zn fluctuated with the temperature and the CFA content. Suitable treatment temperature and CFA content were conducive to the transformation of the heavy metals in the FA into stable forms, and the melting products were no longer hazardous wastes because the vitreous body could effectively encapsulate heavy metals. This study aims to help reuse the FA and CFA collaboratively and be more environmentally friendly.

The resource utilization and stabilization disposal of stainless steel pickling sludge has received more and more attention from domestic and foreign scholars. Here, a sustainable treatment process of low-silica reduction smelting for stainless steel pickling sludge, followed by low-temperature vitrification for the reduced slag, has been proposed. The metal yield can reach more than 98% and metal content in the slag is lower than 0.6% under the optimal conditions of 1400 C temperature, 15% coal ratio, 10% SiO 2 addition, and 1.5 h reaction time. The distinguishable crystal phase in the alloy mainly contained FeNi intermetallic compounds. The reduced slag mainly consisted of fluorite, anorthite, and magnesium silicate. The vitrification experiments implied that it was conducive to increase the vitreous body content of reduced slag via lowering the temperature. The vitreous body content of vitrification products can reach more than 85% when the SiO 2 addition is in the range of 10–20% at 1250°C. This work puts forward a new perspective to achieve both the recovery of valuable metals and the reduction of the slag amount.

Hydro-sodalites are zeolitic materials with a wide variety of applications. Fly ash is an abundant industrial solid waste, rich in silicon and aluminum, from which hydro-sodalite can be synthesized. However, traditional hydrothermal synthesis methods are complex and cannot produce high-purity products. Therefore, there is a demand for processing routes to obtain high-purity hydro-sodalites. In the present study, high-purity hydro-sodalite (90.2wt%) was prepared from fly ash by applying a hydrothermal method to a submolten salt system. Samples were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry and differential thermal analysis (TG-DTA), and Fourier transform infrared spectroscopy (FUR) to confirm and quantify conversion of the raw material into the product phase. Purity of the samples prepared with an H 2 O/NaOH mass ratio of 1.5 and an H 2 O/fly ash mass ratio of 10 was calculated and the conversion process of the product phase was studied. Crystallinity of the product was influenced more by the NaOH concentration, less by the H 2 O/fly ash mass ratio. The main reaction process of the system is that the S i O 3 2 - ions produced by dissolution of the vitreous body in the fly ash and Na + ions in the solution reacted on the destroyed mullite skeleton to produce hydro-sodalite. This processing route could help mitigate processing difficulties, while producing high-purity hydro-sodalite from fly ash.