Search Results (112)

Background/Objectives: Scoliosis in children leads to complex physical, psychosocial, and functional impairments, yet evidence from low-resource settings is limited. To evaluate health-related quality of life (HRQoL) in Ethiopian children with scoliosis using WHODAS 2.0 and EQ-5D-Y, and to identify clinical and demographic correlates of disability. Methods: A hospital-based cross-sectional study was conducted at CURE Children’s Hospital of Ethiopia (1 April 2024–31 March 2025). Ninety-seven children aged 6–15 years with confirmed scoliosis were assessed. WHODAS 2.0 (36-item) captured disability across six domains, while EQ-5D-Y measured physical, psychosocial, and pain-related HRQoL. Clinical severity indicators (Cobb angle, trunk rotation, thoracic morphometrics, anthropometrics) were recorded. Analyses in Python 3.12 included descriptive statistics, correlation, and multiple regression to examine associations between scoliosis severity and HRQoL outcomes. Results: Ninety-seven Ethiopian children diagnosed with scoliosis (mean age 11.4 years, mean Cobb angle 73.5°) were assessed; congenital scoliosis was most common (45.4%), followed by idiopathic (38.1%) and neuromuscular (16.5%). WHODAS 2.0 revealed substantial disability, particularly in mobility (46.4%) and social participation (62.8%), with life activities and participation as the strongest contributors. Greater deformity, younger age, and smaller body size were linked to worse outcomes, with neuromuscular and very severe thoracolumbar cases most affected. EQ-5D-Y showed marked HRQoL impairments across domains, with psychological distress (mean 2.24/3), pain, and self-care limitations emerging as key burdens. The mean EQ score was 8.89/15 (59.2%), indicating reduced quality of life. Regression analyses highlighted pain, psychological distress, and self-care limitations as the domains most strongly associated with poorer HRQoL, while greater Cobb angle and higher ATR degree were also correlated with reduced quality of life. Conclusions: Ethiopian children with scoliosis experience significant multidimensional impairments in HRQoL, with mobility, social participation, pain, and psychological distress as dominant burdens. WHODAS 2.0 and EQ-5D-Y proved complementary in capturing these impacts, supporting their use for early detection, clinical care, and public health planning in resource-limited settings. Full article

Rare earth elements (REEs) flotation from carbonatitic ores remains challenging due to the complex association between REE-bearing minerals and carbonate-rich gangue phases. Although previous studies have reported REE beneficiation from the Fen Deposit, the influence of depressant type, sodium silicate dosage, EDTA addition, and collector selection on flotation selectivity remains poorly understood. Therefore, this study presents a preliminary assessment of different reagent schemes for the flotation of REE-bearing minerals from the Fen Deposit. Chemical and mineralogical characterization confirmed the predominance of light REEs, mainly Ce and La, associated with monazite and fluorocarbonate minerals of the bastnäsite–parisite–synchysite group. Flotation screening tests revealed limited gangue rejection, particularly for Ca- and Ba-bearing minerals, indicating that mineralogical complexity strongly influences flotation selectivity. Among the depressants evaluated, sodium silicate and citric acid exhibited the most promising performance, while EDTA enhanced the total rare earth oxides (TREO) grade at higher sodium silicate dosages. Collector tests resulted in moderate REE enrichment in the overflow products, with NaOL yielding the highest recovery (~62%). However, TREO grades remained relatively low (~2.3–2.7%), suggesting that reagent selection alone is insufficient to overcome the flotation limitations imposed by the ore from the Fen Deposit. The results provide an exploratory evaluation of reagent schemes for Fen carbonatite ore and identify key challenges and opportunities for future process optimization. Full article

Commercial-scale dairy farms produce large volumes of manure, posing environmental, animal health, and public health risks due to persistent pathogens and the accumulation of organic pollutants. This field-scale study evaluated the effects of covered anaerobic lagoons (CLs) and open facultative lagoons (OLs) on microbial reduction, solids stabilization, and manure biogeochemical characteristics on commercial dairy farms in California’s Central Valley during the summer months. Manure samples collected from lagoon inlets, outlets, and secondary lagoons were analyzed for Escherichia coli, total solids (TS), volatile solids (VS), and genomic DNA degradation. CL systems achieved substantially greater E. coli reductions (98.38%; 1.82 log) than OL systems (54.88%; 0.35 log), indicating enhanced pathogen suppression under anaerobic conditions. Progressive declines in genomic DNA concentrations and electropherogram signal intensities across treatment stages further demonstrated microbial biomass degradation during storage. In the CL system, TS concentrations decreased from approximately 0.985% at the inlet to 0.485% at the outlet, representing a 50.7% reduction, with an additional 56% reduction observed in the secondary lagoon. For moisture content, both CL and OL systems exhibited increases of approximately 0.37–0.5% from their respective inlets to outlets, with only marginal increases observed in the secondary lagoon. Comparable trends were observed in the OL system. Significant differences in TS, VS, moisture content, pH, electrical conductivity, and major cations (Na⁺, K⁺, Ca²⁺) occurred between CL and OL systems and among treatment stages. The secondary lagoon further enhanced microbial and solids reductions in both systems. Overall, the findings show that CL systems provide superior pathogen reduction and support biogas recovery, whereas OL systems demonstrate stronger VS stabilization. These results offer practical, field-based insights to inform improved manure management and pathogen mitigation strategies for commercial dairy operations. Full article

Palladium catalysts modified with chitosan (CS) and supported on MgO, SiO₂, TiO₂, and Al₂O₃ were prepared by a precipitation method and evaluated in the low-temperature hydrogenation of 2-propen-1-ol. Chitosan was first deposited onto the oxide supports by adjusting the suspension pH to 7.5, followed by immobilization of palladium via reductive deposition using NaBH₄. For comparison, analogous non-modified catalysts were synthesized. Physicochemical characterization (TGA, XPS, HAADF-STEM, SEM, viscosimetry, and elemental analysis) confirmed successful incorporation of Pd (1 wt.%) and CS (10 wt.%). HAADF-STEM revealed that Pd particle size and aggregation strongly depended on the support nature, with the most uniform distribution observed for Al₂O₃-supported catalysts. Chitosan modification reduced Pd nanoparticle size from 4–11 to 3–4 nm and improved dispersion. XPS showed a pronounced increase in the fraction of oxidized Pd species for the Al₂O₃- and TiO₂-supported catalysts, whereas only minor changes were observed for the SiO₂-based system. For unmodified catalysts, the nature of the oxide support strongly influenced their performance, resulting in a wide variation in catalytic activity (TOF = 1650–13,100 h⁻¹) and selectivity toward propanol (65–75%). Chitosan modification resulted in a support-dependent convergence of catalytic activity (TOF = 3130–8840 h⁻¹) and selectivity (76–81%). Stability tests were performed for Pd–CS(10%)/MgO and Pd–CS(10%)/Al₂O₃, which showed stable performance over 20 cycles without significant loss in catalytic activity. Overall, chitosan modification significantly influences Pd dispersion, oxidation state, and catalytic performance, with effects strongly dependent on the oxide support. Full article

This study investigated the influence of solvent composition on the extraction efficiency and selectivity of phenolic compounds from the Amazonian fruits açaí (Euterpe oleracea) and bacaba (Oenocarpus bacaba). Six choline chloride-based natural deep eutectic solvents (NaDES), combined with different hydrogen bond donors (glycerol, 1,2-propanediol, citric acid, lactic acid, oxalic acid, and urea), were compared with acidified methanol. Extracts were evaluated for total phenolic content (TPC), total flavonoid content (TFC), and antioxidant capacity using FRAP, DPPH, and ORAC assays. In açaí, methanol exhibited the highest TPC and reducing capacity, whereas acid-based NaDESs enhanced phenolic recovery in a matrix-dependent manner. In bacaba, choline chloride–citric acid enhanced total phenolic recovery compared to methanol, highlighting matrix-dependent solvent performance. Differences among FRAP, DPPH, and ORAC responses reflected variations in phenolic composition rather than total concentration alone. HPLC-DAD analysis revealed solvent-selective enrichment of anthocyanins, chlorogenic acid, flavan-3-ols, and rutin, particularly with acid-based NaDES formulations. Molecular docking provided complementary mechanistic insight by indicating favorable interactions between major phenolics and polyphenol oxidase. Overall, the results indicate that choline chloride-based NaDESs can function as tunable extraction systems capable of modulating phenolic profiles in a matrix-dependent manner, representing promising alternatives to conventional organic solvents for phenolic recovery from Amazonian fruits. Full article

In this study, the characteristics of sulfide minerals during the acidic double reverse flotation of phosphate ore and the adsorption mechanisms of sodium oleate (NaOL) and dodecyl trimethyl ammonium bromide (DTAB) were investigated. Micro-flotation test results indicated that NaOL effectively collected galena, sphalerite, and pyrite at a concentration of 1 × 10⁻³ mol/L and pH 4–5.5, whereas DTAB exhibited selectivity for galena at 1 × 10⁻⁴ mol/L. Mixed mineral flotation revealed that NaOL induced a non-selective bulk flotation of sulfides with dolomite, resulting in a high froth yield of 93.23%, while the DTAB system showed superior selectivity with a froth yield of 54.91%. Surface analyses (Zeta potential, FTIR, and XPS) confirmed that NaOL chemisorbs onto sulfide surfaces via metal-oleate complexes, whereas DTAB adsorption is dominated by electrostatic attraction. Bench-scale tests validated the “double-rejection” flowsheet, significantly upgrading the P₂O₅ grade from 23.38% to 31.47% by sequentially partitioning Pb, Zn and Fe into the froth tailings. Size-by-assay analysis indicated that the sulfide separation was primarily controlled by the extent of mineral liberation. These findings provide a robust theoretical framework and practical guidance for the simultaneous management of sulfide minerals during phosphate beneficiation. Full article

Industrial processing of apple to obtain products like juice or cider generates a significant amount of pomace, which represents 25–30% of the fresh fruit mass. Different technologies are needed to valorize apple pomace (AP), considering its significant amount of high-value compounds, such as fiber, vitamins, and polyphenols. Hot-air convection (CA) and infrared (IR) drying are widely used methods for preserving polyphenols from by-products, such as apple pomace (AP), while also extending their shelf life. This study aimed to evaluate the influence of CA and IR drying on drying kinetics, color parameters, and the preservation of polyphenolic compounds, as well as to identify a sustainable extraction approach. Both drying methods significantly affected the color characteristics and content of polyphenols with high antioxidant activity. A significant impact was noticed at higher temperatures, which may be associated with the partial inactivation of browning enzymes. IR drying resulted in a shorter drying time and lower specific energy consumption compared to CA. Furthermore, the assessment of solvent efficiency in ultrasound-assisted extraction (UAE) indicated that the natural deep eutectic solvent (NaDES) composed of choline chloride and glycerol (1:1 molar ratio) provided superior recovery of phenolic compounds with high antioxidant activity compared to conventional solvents and the other NaDES analyzed. Optimization of UAE conditions using this polyol-based NaDES allowed for achieving an extract characterized by a polyphenolic profile dominated by flavan-3-ols (catechin and epigallocatechin), followed by phenolic acids, mainly chlorogenic acid. These results confirm the potential of AP as a valuable source of bioactive compounds and of polyol-based NaDESs as a sustainable and efficient alternative for their recovery. Full article

Fluorite (CaF₂) and barite (BaSO₄) commonly occur together in the same deposits. Due to their similar surface chemical properties, their flotation separation is often challenging. In flotation pulps, dissolved metal ions can further interfere with separation and exert a pronounced influence on the flotation behavior of these minerals. This study investigated the effects of metal ions frequently encountered in industrial pulps (Fe³⁺, Al³⁺, Mg²⁺, Ca²⁺, and Zn²⁺) on the floatability of fluorite and barite in a sodium oleate (NaOL) collector system. The aims were to clarify how metal ions affect flotation behavior and to evaluate the feasibility of enhancing fluorite–barite separation via metal-ion regulation. Flotation results showed that, in the NaOL system, the largest floatability difference between fluorite and barite occurred at pH 10. Al³⁺ exhibited the strongest depression on barite while only weakly affecting fluorite flotation. Fe³⁺ and Mg²⁺ caused slight depression of barite, whereas Ca²⁺ and high concentrations of Zn²⁺ (>20 mg/L) promoted barite flotation. Overall, these metal ions had little influence on fluorite flotation. Adsorption measurements indicated that Al³⁺ reduced NaOL adsorption by more than 40% and decreased the contact angle from 35.6° to 23.1°, resulting in a sharp loss of surface hydrophobicity. ICP adsorption tests revealed that Al³⁺ showed the highest uptake on barite surfaces. Density functional theory (DFT) calculations further confirmed that surface SO₄²⁻ groups on barite form strong chemisorption with hydrolyzed Al species (adsorption energy: −436.19 kJ/mol), whereas only weak physisorption occurs on hydroxylated fluorite surfaces (adsorption energy: −43.73 kJ/mol). This study provides insights into the flotation separation of non-metallic minerals dominated by polar ionic bonding and offers practical guidance for efficient fluorite–barite separation under complex ionic environments. Full article

Biosurfactants produced by halophilic bacteria are gaining attention as eco-friendly and biocompatible alternatives to synthetic surfactants due to their high surface activity, stability under extreme conditions, and intrinsic antimicrobial properties. These amphiphilic biomolecules hold great promise for bioremediation, biomedical, and pharmaceutical applications. In this study, moderately halophilic bacteria capable of biosurfactant production were isolated from saline mud collected at the Burgas solar salterns (Bulgaria). The halophilic microbiota was enriched in Bushnell–Haas (BH) medium containing 10% NaCl amended with different carbon sources. Primary screening in BH liquid medium evaluated the isolates’ ability to degrade n-hexadecane while at the same time producing biosurfactants. Thirty halophilic bacterial strains were isolated on BH agar plates supplemented with 2% n-hexadecane, 2% olive oil, or 2% glycerol. Four isolates—BS7OL, BS8OL, BS9GL, and BS10HD—with strong emulsifying activity (E₂₄ = 56%) and reduced surface tension in the range of 27.3–45 mN/m were derived after 7 days of batch fermentation. Strain BS10HD was chosen as the most potent biosurfactant producer. Its phylogenetic affiliation was determined by 16S rRNA gene sequence analysis; according to the nucleotide sequence, it was assigned to Halomonas ventosae. The extract material was analysed by thin-layer chromatography (TLC) and Fourier transform infrared spectroscopy (FTIR). Upon spraying the TLC plate with ninhydrin reagent, the appearance of a pink spot indicated the presence of amine functional groups. FTIR analysis showed characteristic peaks for both lipid and peptide functional groups. Based on the observed physicochemical properties and analytical data, it can be suggested that the biosurfactant produced by Halomonas ventosae BS10HD is a lipopeptide compound. Full article

Polyelectrolyte-based complexes have attracted attention, as the interaction of the oppositely charged components results in nanoparticle formation through an easy but highly efficient method, avoiding the use of strong solvents, extreme temperatures, and toxic chemicals. Sodium oleate (NaOL) is a widely used surfactant in the pharmaceutical industry due to its availability, eco-friendliness, and low cost. In the present study, the neutral-cationic block copolymer poly(oligo(ethylene glycol) methyl ether methacrylate)–b–quaternized poly(2-(dimethylamino) ethyl methacrylate) (POEGMA-b-Q(PDMAEMA)) is mixed with the anionic surfactant sodium oleate for the formation of nanoscale polyelectrolyte complexes through electrostatic interactions. Different weight ratios of copolymer to surfactant are studied. Then, the co-solvent protocol was implemented, and curcumin is successfully loaded in the formed particles for drug delivery applications. The size and morphology of the macromolecular complexes are examined via Dynamic Light Scattering (DLS) and Cryogenic Transmission Electron Microscopy (cryo-TEM). The methods that we have used have indicated that the polymer–surfactant complexes form spherical complexes, worm-like and vesicle-like structures. When curcumin was introduced, encapsulation was effectively achieved into micelles, giving rise to vesicle-like shapes. The success of curcumin encapsulation is confirmed by Ultraviolet–Visible absorption (UV–Vis) and fluorescence (FS) spectroscopy. POEGMA-b-Q(PDMAEMA)–sodium oleate polyelectrolyte complexes revealed promising attributes as efficient drug carrier systems for pharmaceutical formulations. Full article

Calcium ions, primarily introduced through flotation reagents and mineral dissolution, progressively accumulate a considerable amount due to the process of water recycling, significantly impacting the flotation behavior of minerals. In this paper, the adsorption of calcium ions on a calcite surface was initially studied by surface characteristic analysis, and then further evaluated for its influence on the separation of scheelite from calcite using single mineral flotation and atomic force microscopy (AFM) measurements. The results indicate that calcium ions significantly reduce the hydrophobicity of calcite surface induced by sodium oleate (NaOL) adsorption, while enhancing the adsorption of sodium silicate (SS). In addition, SS forms a strong chemical adsorption on calcite, rendering the surface negatively charged. However, the surface charge diminishes under the combined influence of calcium and silicate ions. AFM measurements further reveal that the adhesion forces between scheelite and calcite are weakened by silicate adsorption. Nevertheless, these forces are markedly restored in the presence of calcium ions, thereby considerably reducing the selectivity of SS and hindering effective particle separation. These findings align with the results of mixed binary flotation, confirming that calcium ions indeed interfere with the separation of scheelite from calcite. Full article

Flotation separation of fluorite and calcite, by adding AWG (acidified water glass) as inhibitor and NaOL (sodium oleate) as collector, has been investigated by means of micro-flotation tests, flotation solution chemistry, zeta potential measurements, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) in this study. The micro-flotation results demonstrate that NaOL exhibits strong collecting power toward both fluorite and calcite, making effective separation of the two minerals unachievable in the absence of depressants. When AWG is applied as a depressant, it shows selective depression toward calcite, while exhibiting little effect on fluorite. Solution chemistry analysis, contact angle measurements, zeta potential measurements, FTIR, and XPS analyses collectively confirm that AWG can adsorb onto the calcite surface, but not onto fluorite. This adsorption prevents NaOL from interacting with the calcite surface. In contrast, the absence of AWG adsorption on fluorite allows NaOL to freely adsorb and thereby collect fluorite particles. Full article

Extensive studies have established that ultrasonic micro-jets and acoustic cavitation selectively intensify interfacial interactions at multiphase boundaries, thereby enhancing the flotation of soluble salt minerals and oxide ores. Although a growing body of evidence shows that pulp-borne nanoparticles (i.e., nanosolids, colloids, and nanoscale gas nuclei) mediate these effects, their role in the flotation of ultrafine smithsonite after collector addition has not yet been systematically examined. To fill this gap, we compared the flotation response of ultrafine smithsonite under conventional stirring (SC) and ultrasonic conditioning (UC), using sodium oleate (NaOL) as the collector, and dissected the governing mechanisms across three pillars, mineral–NaOL interaction, particle aggregation, and frothability, with particular attention paid to how nanoparticles modulate each dimension. The flotation results show that flotation performance under UC is dictated by NaOL concentration. At low NaOL levels (i.e., below 4 × 10⁻⁴ M), UC depresses both recovery and kinetics relative to SC, while at high NaOL levels, the trend reverses and UC outperforms SC. Mechanistic analysis reveals that sonication erodes mineral surfaces and generates cavitation, flooding the pulp with various nanoparticles. When NaOL is scarce, zinc-containing components and zinc-rich nanosolids sequester the collector through non-selective adsorption and precipitation, leaving smithsonite poorly hydrophobized. Consequently, particle aggregation and pulp frothability are markedly inferior to those in the SC system, so the flotation recovery and kinetics remain lower. As the NaOL concentration rises, smithsonite becomes adequately hydrophobized, and the pulp fills with hydrophobic zinc-rich nanosolids, along with cavitation-induced gas nuclei or tiny bubbles. These nanoparticles now act as bridges, accelerating the aggregation of ultrafine smithsonite once sonication stops and agitation begins, while simultaneously improving frothability. Although the strong dispersive action of ultrasound still suppresses initial flotation kinetics, cumulative recovery ultimately surpasses that of SC. The findings delineate a nanoparticle-regulated flotation paradigm and establish a critical NaOL concentration window for effective UC in ultrafine smithsonite flotation. This framework is readily transferable to the beneficiation of other ultrafine, soluble oxidized minerals (rhodochrosite, dolomite, etc.). Full article

Although opioids are effective in treating pain, they cause serious side effects. The use of regional anesthesia, although effective in the perioperative period, may not be suitable if mobility and lack of numbness is desired. Hence, there is a clear need for novel pain therapies. Low-voltage activated (T-type) calcium channels (Ca_V3.2 isoform) could be a promising therapeutic target for the development of novel pain therapies. Indeed, our published findings suggest that novel neuroactive steroid (NAS) analogs that modulate the activity of Ca_V3.2 channels have unique anti-nociceptive properties. However, the concern with current NASs appears to be their hypnotic/sedative properties, thus potentially hindering the future development of NASs for novel pain therapies. Hence, we developed a new line of NASs that are effective blockers of neuronal Ca_V3.2 channels in pain pathways while having more favorable pharmacodynamic properties, i.e., lack of sedative/hypnotic side effects. We present two promising novel analogs of NASs—B372 ((3β,5α,17β)-3-Hydroxyandrostan-17-carbonitrile) and YX23 ((3β,5α,17β)-3-Methoxyestran-17-ol). Using an in vitro approach, we show that B372 and YX23 are effective in blocking Ca_V3.2 channels. Using an in vivo approach, we show that they are effective anti-nociceptives in wild-type but not Ca_V3.2 knock-out mice. Importantly, we show that they lack sedative/hypnotic effects. Full article

Developments of new research tools in flotation studies, including bubble–particle attachment time efficiency and dynamic froth analysis, can help improve our understanding of particle–bubble interactions in flotation processes. In particular, the selection of new collectors and frothers, and their mixtures can provide a wide distribution of bubble sizes at their respective concentrations. In the literature, several studies have reported the effect of different frothers and collector mixtures on bubble characteristics like bubble size and critical coalescence concentration (CCC). The general trend obtained from these studies showed that the addition of frothers, along with collectors, which also act as frothers during flotation, resulted in finer bubbles and required lower concentrations of frothers, which in turn positively affected the flotation recoveries. In this study, an attempt was made to study fine-sized magnesite in the presence of sodium oleate (NaOL) and five different types of frothers (PPG600, PPG400, BTPG, BDPG, and MIBC). Bubble–particle attachment time with different sized capillary tubes and dynamic froth analysis values in a liquid–air system, along with flotation recoveries in a micro-flotation cell, were interpreted to show possible correlations and provide an optimum bubble/particle size ratio in the presence of different frothers. Full article