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Background: The correlation between thalassemia and malignancies other than hepatocellular carcinoma (HCC) and the possible relationship between other hemoglobinopathies and tumor risk have been poorly evaluated. Methods: Eight Italian specialized centers evaluated the incidence of malignant neoplasms in hemoglobinopathies as well as their sites and features. The study cohort included 4631 patients followed between 1970 and 2021 (transfusion‐dependent β‐thalassemia, 55.6%; non–transfusion‐dependent thalassemia, 17.7%; sickle cell disease, 17.6%; hemoglobin H disease, 8.3%). Results: A total of 197 diagnoses of cancer were reported (incidence rate, 442 cases per 100,000 person‐years). The liver was the most frequent site of tumors in both sexes, with a higher incidence (190 cases per 100,000 person‐years) in comparison with the general population found in all types of hemoglobinopathies (except hemoglobin H disease). In recent years, tumors have become the second cause of death in patients with transfusion‐dependent thalassemia. A lower risk of breast and prostate cancer was observed in the whole group of patients with hemoglobinopathies. The first cancer diagnoses dated back to the 1980s, and the incidence rate sharply increased after the 2000s. However, although the incidence rate of cancers of all sites but the liver continued to show an increasing trend, the incidence of HCC showed stability. Conclusions: These findings provide novel insights into the relationship between cancer and hemoglobinopathies and suggest that the overall risk is not increased in these patients. HCC has been confirmed as the most frequent tumor, but advances in chelation and the drugs that have led to the eradication of hepatitis C may explain the recent steadiness in the number of diagnoses that is reported here. Except for hepatocellular carcinoma, cancers are not more frequent in patients with hemoglobinopathies in comparison with the general Italian population. The incidence of hepatocellular carcinoma over time showed an increasing trend until 2012; since then, there has been a steady number of new diagnoses despite the increasing age of patients with hemoglobinopathies. [ABSTRACT FROM AUTHOR]

Electrical conductivities of polycrystalline garnets ranging in chemical composition from almandine ([Fe.sub.3][Al.sub.2][Si.sub.3] [O.sub.12]) to pyrope ([Mg.sub.3][Al.sub.2][Si.sub.3][O.sub.12]) were measured at 10 GPa and 19 GPa at temperatures ranging from 300 to 1700[degrees]C using complex impedance spectroscopy in a multianvil device. Mossbauer spectroscopy of each sample was carried out both before and after the electrical measurements to characterize the oxidation state of Fe in the almandine bearing garnets. Similar to the behavior of other ferromagnesian silicates, the substitution of Fe for Mg along this compositional join dramatically increases electrical conductivity, but this compositional effect is reduced with increasing temperature. Conductivities increase with increasing total Fe content, as the average [Fe.sup.2+]-[Fe.sup.3+] distance decreases. At 10 GPa, activation energies for conductivity vary smoothly with composition and increase rapidly toward the pyrope end-member composition, where it reaches a value of 2.5 eV. The results are consistent with an electrical conductivity mechanism involving small polaron mobility in the Fe-bearing garnets at 10 GPa. At 19 GPa, however, there is virtually no change in the activation energy as a function of Fe-Mg substitution for the pyrope-rich garnets. These higher pressure measurements reflect a mechanism involving oxygen related point defects, as conductivities increase with pressure at constant T for each garnet, and the effect of pressure is greater for the more Mg-rich garnets. The data also allow for a more quantitative evaluation of the effect of chemical composition, specifically Fe-Mg substitution, on the electrical conductivity profile of the mantle, using a recently developed laboratory-derived model. We apply the model using these data to a portion of the transition zone between 520 and 660 km, in which we vary the garnet composition from [Py.sub.100] to [Py.sub.85] [Alm.sub.15]. Although only a minor effect on bulk mantle conductivity results, we conclude that the overall garnet composition may, however, be important in characterizing the magnitude of any EC discontinuity with respect to the above-lying mantle. Keywords: Electrical conductivity, pyrope-almandine, high pressure, cation substitution

The local structure of vanadium (V) in synthetic glasses of basaltic composition has been studied by means of high-resolution V K-edge X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy to obtain quantitative data on distances. V coordination number (CN), and oxidation state. The compositions and experimental conditions were chosen so as to verify the effect of bulk-glass composition (using a diopside-anorthite composition, a sodium disilicate glass, and an iron-titanium-bearing basaltic glass) and V content (from 0.1 to 5 [V.sub.2][O.sub.5] wt%) on the structural role of V in these glasses. The combined analysis of high-resolution XANES spectra and EXAFS data indicate that on average, the Fe-free glasses synthesized in air show vanadium in the [V.sup.5+] state, mainly in tetrahedral coordination (less than 20% [sup.[5]][V.sup.5+] and with distances of 1.697 ([+ or -] 0.020) [Angstrom], in agreement with the values found for tetrahedral V in minerals. In contrast, the Fe-bearing basaltic glasses display a mixture of [V.sup.5+] in fourfold and fivefold coordination, 40% [sup.[4]][V.sup.5+]-60% [sup.[5]][V.sup.5+] in proportion, and the EXAFS-derived distances and coordination numbers are in agreement with this interpretation. No significant changes in the V local structure were found in the glasses analyzed as a function of V-contents in the 0.1 to 5 [V.sub.2][O.sub.5] wt% range. The data obtained suggest that the structural role of vanadium in these melts is rather insensitive to bulk composition, in terms of V and alkali content, but can be strongly affected by the presence of other transition elements, e.g., [Fe.sup.3+] competing with V to enter the tetrahedral framework.

We have measured multicomponent chemical diffusion coefficients in a melt near to the low pressure water-saturated eutectic granite composition in the system [K.sub.2]O-[Na.sub.2]O-[Al.sub.2][O.sub.3]Si[O.sub.2]-[H.sub.2]O at 1.0 GPa and temperatures of 1300 and 1600 [degrees] C. The measured diffusion profiles can be accounted for within the analytical error by diffusion coefficients, which are not dependent on composition within the range of compositions accessed by our experiments. The multicomponent diffusion coefficient matrix [D] has a highly degenerate set of real, positive eigenvalues that show a regular relation to melt viscosity on an Arrhenius diagram. The smallest eigenvalue is that associated predominantly with Si-Al exchange. The larger two eigenvalues are those associated with Si-Na and Si-K exchange and are effectively degenerate, with the result that exchanges of alkalis for silica or for each other can proceed in pseudo-binary fashion without inducing fluxes of other components. The eigenvalne associated with H-Si exchange is smaller than the alkali-silica eigenvalues, but analytical uncertainties make it also effectively degenerate with the alkalis. Uphill diffusion, notably of water and alkalis, was observed in several experiments, and this would lead to transient partitioning of water and alkalis across diffusion interfaces showing large [Al.sub.2][O.sub.3] concentration gradients. Such partitioning in natural systems would persist until Al concentration gradients were erased by continued, much slower Al-Si interdiffusion.

A new method, based on the principle that volume relaxation of the melt influences the rate of contraction of inclusion cavities during quenching, helps determine the glass transition temperature of hydrous silicate melts at high pressure. A microscope heating-stage assembly helps evaluate the liquid-vapor homogenization temperatures of the trapped inclusion. Kinetic studies reveal the nonlinear dependence of glass transition on the composition. This method enables the determination of glass transition temperature in seven compositions on the join albite-orthoclase.