Intradiscal quantitative chemical exchange saturation transfer MRI signal correlates with discogenic pain in human patients

Low back pain (LBP) is often a result of a degenerative process in the intervertebral disc. The precise origin of discogenic pain is diagnosed by the invasive procedure of provocative discography (PD). Previously, we developed quantitative chemical exchange saturation transfer (qCEST) magnetic resonance imaging (MRI) to detect pH as a biomarker for discogenic pain. Based on these findings we initiated a clinical study with the goal to evaluate the correlation between qCEST values and PD results in LBP patients. Twenty five volunteers with chronic low back pain were subjected to T2-weighted (T2w) and qCEST MRI scans followed by PD. A total of 72 discs were analyzed. The average qCEST signal value of painful discs was significantly higher than non-painful discs (p = 0.012). The ratio between qCEST and normalized T2w was found to be significantly higher in painful discs compared to non-painful discs (p = 0.0022). A receiver operating characteristics (ROC) analysis indicated that qCEST/T2w ratio could be used to differentiate between painful and non-painful discs with 78% sensitivity and 81% specificity. The results of the study suggest that qCEST could be used for the diagnosis of discogenic pain, in conjunction with the commonly used T2w scan.

Application of robust parameter design in the development of a quantitative chemical analysis procedures in metallurgy

The paper presents the results of experimental research for the quantitative chemical analysis procedures using the robust parameter design methodology. There is an example of the parameter design in development of the measurement procedure for the mass fraction of chlorine in dusty waste in the ferronickel production. Results of experiment analysis has provided an information about the optimal conditions for sample preparation procedure.

A Promising Method of Utilization of Ash and Slag Waste of Variable Composition at Coal-fired Power Plants

A comparative analysis of ash and slag waste (ASW) of six deposits, differing in quantitative chemical and phase composition, granulometry, melting temperature and other properties, is presented, and the production of a material promising for the construction industry is proposed – aggloporite, the production technology of which practically does not depend on the composition and properties of TPP ash. Aggloporite can also be used in road construction to form side slopes. The proposed method of recovery of large volumes of ash and slag waste accumulated at a number of power plants opens up opportunities to improve the environmental situation in the areas located in the vicinity of coal power plants, free up significant land areas occupied by ash and slag waste storage facilities, and reduce the harmful effect of waste on soil, water and air.

Conventional synthesis of perovskite structured LaTixFe1-xO3: A comprehensive evaluation on phase formation, opto-magnetic, and dielectric properties

Perovskite structured LaTixFe1-xO3 (x = 0, 0.05, 0.15, 0.25) lanthanum ferrites were synthesized by conventional solid-state reaction. The structural Rietveld refinement and Raman analysis were conducted and confirmed that single-phase orthorhombic phase with Pbnm symmetry formed. The positions of the ions and their bonds of these ferrites were investigated. The spherical shaped morphology of these ferrites was examined. The quantitative chemical composition and distribution of these ferrites were confirmed. The excitonic absorption edge was observed at 590 nm; ascribed to the electronic transition from O2p→Fe3d and optical band gap values increased from 1.85– 2.02 eV as Ti concentration increased. The dielectric and magnetic behavior of these ferrites was studied. It is suggested that synthesized LaTixFe1xO3 powders with different properties could be tailored for different requirements.

Allantoin and Natrosulfatourea, Two New Bat-Guano Minerals from the Rowley Mine, Maricopa County, Arizona, USA

ABSTRACT The new minerals allantoin (IMA2020–004a), C4H6N4O3, and natrosulfatourea (IMA2019–134), Na2(SO4)[CO(NH2)2], were found in the Rowley mine, Maricopa County, Arizona, USA, where they occur together in bat guano in association with aphthitalite and urea. Allantoin properties: colorless, transparent, untwinned blades to 0.3 mm; white streak; vitreous luster; brittle; Mohs hardness 1½; conchoidal fracture; good {100} cleavage; 1.72(2) g/cm3 density; biaxial (+) with α = 1.558(2), β = 1.593(2), γ = 1.715(3); 2V = 60(1)°; slight r > v dispersion; optical orientation: Y = b, Z ^ a = 30° in obtuse β. Natrosulfatourea properties: colorless, transparent, untwinned prisms to 0.3 mm; white streak; vitreous luster; brittle; Mohs hardness 1½; irregular fracture; perfect {100} cleavage; 1.97(2) g/cm3 density; biaxial (+) with α = 1.456(2), β = 1.464(5), γ = 1.524(2); 2V = 42(1)°; no dispersion; optical orientation: X = a, Y = c, Z = b. Quantitative chemical analyses could not be obtained for allantoin. Electron microprobe analyses provided the empirical formula Na2.02(S0.98O4)[CO(NH2)2] for natrosulfatourea. Allantoin is monoclinic, P21/c, a = 8.0304(9), b = 5.1596(5), c = 14.8011(18) Å, β = 93.017(7)°, V = 612.41(11) Å3, and Z = 4. Natrosufatourea is orthorhombic, Pbcn, a = 5.5918(4), b = 18.1814(14), c = 6.7179(5) Å, V = 682.98(9) Å3, and Z = 4. The crystal structure of allantoin (R1 = 0.0432 for 1073 I > 2σI) is the same as that reported for the equivalent organic compound. In the structure of natrosulfatourea (R1 = 0.0413 for 785 I > 2σI) NaO6 polyhedra and SO4 tetrahedra form polyhedral layers. The O atom of the CO(NH2)2 (urea) group ligates to two Na atoms and projects into the space between polyhedral layers, linking adjacent layers through hydrogen bonds.