Lattice dynamic calculations for the sepiolite and palygorskite structures using polarized Raman and FTIR spectra provide a fundamental basis for interpreting spectral features by assigning vibrational modes. The Si-O stretch and O-Si-O bond bending force constants determined for palygorskite are similar to equivalent values calculated previously for other phyllosilicates. The Mg-O bond stretch values, on the other hand, are about half of those determined for the equivalent Al-O and Mg-O bond stretch environments in other phyllosilicates, suggesting that the bonding within the octahedral ribbons in palygorskite and sepiolite is weaker than that in the continuous octahedral sheets in micas. The weaker bonding allows more flexible octahedral environments in palygorskite and sepiolite, giving rise to higher probabilities for cation substitutions and vacancies relative to the micas. Above ∼700 cm−1 in the IR and 750 cm−1 in the Raman spectra, the eigenmodes are dominated by atomic displacements within the silicate sheets. Below 700 cm−1 the eigenmodes become mixed with motions among the Mg octahedra and the silicate sheets; the eigenmodes assigned to the most prominent peaks in the Raman spectra (near 700 cm−1) belong to this group. As mode frequencies decrease, the corresponding eigenmodes evolve from more localized Mg-O stretch, O-Mg-O bend and O-Si-O bend motions to longer-range motions such as silicate sheet deformations caused by silicate tetrahedra rotation and silicate sheet shearing around the Mg-octahedral sheets.

Hepatitis A virus (HAV) infection is a notifiable disease in Ireland, with national coverage of clinical and laboratory surveillance. In December 2020, a cluster of 11 HAV cases among the Irish Traveller community was detected. The outbreak investigation identified 61 total HAV cases from September 2020 to November 2021. Sequenced isolates were sub-genotype IA with identical genome sequence. Case-patients were predominantly aged under 18 (77%), hospitalised (46%) and lived on communal residential sites. Mass onsite HAV vaccination was employed following failure of initial ring vaccination to contain the outbreak. This is the largest outbreak of HAV described in Ireland, involving spillover to the UK and Netherlands. We recommend mass HAV vaccination and tailored communication for outbreak control in migratory subpopulations.

Highly crystalline core-shell FeCo-CoFe2O4 nanowires were obtained from a three step process. Initially, CoFe2O4 nanowires were grown using electrospinning and annealing at higher temperatures. Through a thermal reduction under controlled conditions, CoFe2O4 nanostructures were converted to FeCo alloy nanowires. Then by natural oxidation, a highly crystalline shell of CoFe2O4 formed over the FeCo core structure. Structural and magnetic characterizations revealed the presence of highly crystalline FeCo-Co2FeO4 core-shell structure. Magnetically, the soft FeCo phase switches at a lower magnetic field compared to the hard CoFe2O4 phase, yielding an irregular hysteresis loop with a squeezed loop in the middle. The FeCo/CoFe2O4 core-shell is stable and it retains its structure for a prolonged duration.

The potential to reduce cardiovascular morbidity through dietary modification remains an area of intense clinical and scientific interest. Any putatively beneficial intervention should be tested within a randomised controlled trial which records appropriate endpoints, ideally incident CVD and death. However, the large sample sizes required for these endpoints and associated high costs mean that the majority of dietary intervention research is conducted over short periods among either healthy volunteers or those at only slightly increased risk, with investigators using a diverse range of surrogate measures to estimate arterial health in these studies. The present review identifies commonly employed techniques, discusses the relative merits of each and highlights emerging approaches.

Technetium (Tc), found in some nuclear wastes, is of particular concern with regard to long-term storage, because of its long-lived radioactivity and high mobility in the environment. Tc and rhenium (Re), commonly used as a non-radioactive surrogate for Tc, were studied to assess their behavior in borosilicate glass under hydrothermal conditions in the Vapor Hydration Test (VHT). X-ray absorption spectroscopy (XAS) and scanning electron microscopy (SEM) measurements were made on the original Tc- and Re-containing glasses and their corresponding VHT samples, and show different behavior for Tc and Re under VHT conditions. XAS indicates that, despite starting with different Tc(IV) and Tc(VII) distributions in each glass, the VHT samples have 100% Tc(IV)O6 environments. SEM shows complete alteration of the original glass, Tc enrichment near the sample surface, and Tc depletion in the center. Perrhenate (Re(VII)O4−) is dominant in both Re-containing samples before and after the VHT, where Re is depleted near the VHT sample surface and more concentrated toward the center.

A series of glass samples were prepared analogously to high level waste glass using either glass frit or glass precursors combined with a high level waste surrogate containing NaTcO4. Three different technetium species were observed in these glasses depending upon the synthesis conditions. If the glasses were prepared by reducing NaTcO4 to TcO2•2H2O with hydrazine or if a large amount of organic material was present, inclusions of TcO2 were observed. If no organic material was present, technetium was incorporated as TcO4−. If only a small amount of organic material was present, isolated Tc(IV) sites were observed in the glass. The relative technetium retention of these glasses was estimated from the Tc K-edge height, and had no correlation with the oxidation state of the technetium. Pertechnetate was well retained in these glasses.

XANES and EXAFS data were collected and analyzed to characterize vanadium in borosilicate glasses used for immobilization of sulfur-containing nuclear wastes. Earlier studies suggested that adding vanadium to the melt improves sulfur solubility. Data are presented for a variety of borosilicate glasses, some containing sulfur and some sulfur-free, that have V2O5 concentrations as high as 12 wt%, and for crystalline vanadium sulfide, silicate, and oxide standards. The data for all glasses investigated indicate that most or all vanadium has a +5 valence and is tetrahedrally coordinated by oxygen atoms. Both XANES and EXAFS also show that glasses synthesized under reducing conditions can have pentacoordinated V+4 populations up to approximately 20 to 25% of all vanadium present with the remainder being V+5O4. There is no evidence from XANES or EXAFS of V-S bonds in any of the glasses investigated.

A range of compositions of high-zirconia borosilicate glasses were formulated and their structures investigated by a combination of techniques. These compositions have potential applications for high-level nuclear waste storage in combination with advanced reprocessing methods. Raman and Zr EXAFS data were collected for a series of glasses spanning a range of zirconia concentrations. The Raman spectra indicate that Zr acts as a silicate network modifier, where the silicate tetrahedral network depolymerizes as the zirconia content increases. Zr EXAFS analysis indicates that Zr is found in octahedral sites, and to a minor extent, sevencoordinated sites. As the zirconia content increases, the fraction of seven-coordinated Zr-sites increases; this may be the cause of ZrO2 baddeleyite crystallization that was observed in some Zr-rich glasses investigated.

X-ray absorption spectroscopy has been used to characterize the local structure surrounding Ga and Ge in BaO-Ga2O3-GeO2 glasses. Based on comparisons with results for crystalline standards of known structure, Ge and Ga in all of the glasses are primarily in tetrahedral coordination; no evidence for octahedral coordination is observed. Bond length and coordination values derived from fitting calculations are fairly uniform for all glasses, however disorder increases with increase in BaO and decrease in GeO2 content, especially in the second shell surrounding Ge and Ga. Ge absorption edges for all glasses resemble smoothed BGG-An or GeO2 [quartz] edges. Ga absorption edges of the glasses also resemble the BGG-An edge which has two edge maxima, but in the glasses the relative intensities of the two maxima vary with composition.

XANES and EXAFS data indicate that chrysocolla does not contain domains of Cu-metal or Cu-oxides as previously hypothesized, but is most similar to dioptase, a chemically homogeneous crystalline Cu-silicate. The first shell around Cu in chrysocolla is similar to that in dioptase, indicating Cu is coordinated by four oxygens. However, the second shell around Cu in chrysocolla is significantly different than the second shell surrounding Cu in dioptase. The larger amplitude second shell for chrysocolla compared with dioptase is found to be primarily due to differences in the Cu-Cu environments between these two materials.