Features of the distribution of molecular hydrogen in groundwater in various geological and tectonic conditions of Uzbekistan

As a result of generalization and analysis of previously performed work on the determination of hydrogen on the day surface, a picture of the distribution of hydrogen concentration in the aeration zone was obtained. The increased concentration of hydrogen on the day surface and in the aeration, zone is associated with the most favourable conditions for the transit of fluids from the folded Palaeozoic basement to the surface cover (upper part of the Earth’s crust). These zones are zones of active fluid conductivity, which leads to a high concentration of hydrogen on the day surface. Intense linear anomalies are confined to the zone of intersection of the Tuzkoy-Rometan transverse fault with the Bukhara-Gissar regional fault, with which seismic events are associated (epicentres Gazli earthquakes occurred 08.04.1976, 17.05.1976 and 19.03.1984). Analysis of long-term observations of gas composition on an example of molecular hydrogen in groundwater southwestern part Karzhantaus fault, covering the territory of Tashkent city and its surroundings, obtained hydrogen concentration distribution pattern area. A different concentration of hydrogen in the fault zone was revealed, associated with the heterogeneity of the geological and structural structure.

Anomalous normal fluid response in a chiral superconductor UTe2

Chiral superconductors have been proposed as one pathway to realize Majorana normal fluid at its boundary. However, the long-sought 2D and 3D chiral superconductors with edge and surface Majorana normal fluid are yet to be conclusively found. Here, we report evidence for a chiral spin-triplet pairing state of UTe2 with surface normal fluid response. The microwave surface impedance of the UTe2 crystal was measured and converted to complex conductivity, which is sensitive to both normal and superfluid responses. The anomalous residual normal fluid conductivity supports the presence of a significant normal fluid response. The superfluid conductivity follows the temperature behavior predicted for an axial spin-triplet state, which is further narrowed down to a chiral spin-triplet state with evidence of broken time-reversal symmetry. Further analysis excludes trivial origins for the observed normal fluid response. Our findings suggest that UTe2 can be a new platform to study exotic topological excitations in higher dimension.

Cation-Exchange Capacity Distribution within Hydrothermal Systems and Its Relation to the Alteration Mineralogy and Electrical Resistivity

Cation-exchange capacity (CEC) measurements are widely used to quantify the smectite content in altered rocks. Within this study, we measure the CEC of drill cuttings in four wells from three different high-temperature geothermal areas in Iceland. The CEC measurements in all four wells show similar depth/temperature related pattern, and when comparing the CEC with electrical resistivity logs, we could show that the low resistivity zone coincides with CEC values >5 meq/100 g. The measurements show, in general, an exponential decrease of the CEC with increasing depth. At the facies boundary between the mixed-layer clay and epidote-chlorite zone, the CEC reaches a steady state at about 5 meq/100 g and below that it only decreases slightly within a linear trend with increasing depth. The facies boundary overlaps with the transition where the electrical resistivity logs show an increase in resistivity. It is shown that the measured CEC can be related to the clay mineral alteration within the geothermal system and the CEC reflects the smectite component within the interstratified chlorite/smectite minerals for similar alteration degree. Furthermore, CEC was measured in seven core samples from different alteration zones that had previously been studied in detail with respect to petrophysical and conductivity properties. The results show a clear correlation between CEC and the iso-electrical point, which describes the value of the pore fluid conductivity where transition from surface conductivity to pore fluid conductivity occurs. The presented study shows that the CEC within hydrothermal altered basaltic systems mimics the expandable clay mineral alteration zones and coincides with electrical logs. The presented method can, therefore, be an easy tool to quantify alteration facies within geothermal exploration and drilling projects.

P1214RELATIONSHIP BETWEEN CHANGE IN DIALYSATE CONDUCTIVITY AND INTRAPERITONEAL VOLUME DURING PET

Background and Aims Bioimpedance spectroscopy (BIS) has been widely applied to measure fluid volume in dialysis patients. A fundamentally important, yet unanswered question is how changes in fluid conductivity affects the accuracy of BIS measurements. The aim of this study was to investigate whether the change in intraperitoneal volume (IPV) is – as hypothesized - linearly correlated with the change in dialysate conductivity during a peritoneal equilibrium test (PET). Method Four PD patients (age 58±13 years, three males, weight 87.8±28 kg) were studied during a standard PET. Segmental BIS was continuously measured with eight electrodes placed between rib and buttock on both sides of the body using a Hydra 4200 (Xitron Technologies Inc ). IPV was calculated based on BIS recordings as recently published (Zhu, Kidney Blood Press Res 2019;44:1465–1475). Dialysate samples were collected hourly from baseline to the end of dwell. Dialysate conductivity was measured with a portable conductivity meter (CDH-280-KIT, Omega Engineering Inc, CT, USA). Results In all patients dialysate conductivity increased significantly (p<0.0001) from baseline (11.14±0.15 mS/cm) to the end of dwell (12.5±0.58 mS/cm) (Fig a). In 2 patients (Fig b and c) IPV and conductivity were linearly correlated; in one patient (Fig d) the relationship was nonlinear and absent in another one (Fig e). Conclusion Although the number of patients in this study was small, the results clearly indicated that dialysate conductivity increased linearly over time during PET. The correlation between dialysate conductivity and IPV is not linear and may be driven by other factors, such as dialysate electrolyte levels. In future studies measurements of dialysate electrolytes are necessary to better understand the drivers of the IPV / conductivity relationship.

Iris and its relevance to angle closure disease: a review

Glaucoma is a leading cause of irreversible visual impairment, and primary angle closure glaucoma (PACG) affects Asians disproportionately. Whereas advances in ocular imaging have identified several anatomical risk factors, our ability to predict PACG still requires considerable improvement. The iris plays a crucial role in the pathophysiology of angle closure disease, either through a mechanical or vascular mechanism. Irises of closed-angle eyes inhibit vastly different structural constituents as compared with those of open-angle eyes, thereby effecting variations in biomechanical properties and iris fluid conductivity. The clinical consequences include a smaller change in iris volume on pupil dilation in closed-angle eyes, thereby bringing the iris and trabecular meshwork closer in apposition. In this review, we summarise the potential role of the iris in the pathogenesis of angle closure disease.