Assessment of the degree of violations of hemostasis parameters, rheology, markers of inflammation in patients with arterial hypertension and different risks of venous thromboembolic complications

The aim of the work is to investigate the parameters of hemostasis, electrical and viscoelastic parameters of red blood cells and markers of inflammation in persons suffering from arterial hypertension to determine the possibility of assessing the severity of hemorheological disorders.Material and methods. The study included 203 patients (156 patients with arterial hypertension and 47 patients without hypertension). The parameters of hemostasis, markers of inflammation and red blood cells were studied.Results. The possibilities of assessing the severity of hemorheological disorders in patients with arterial hypertension, based on the study of parameters: hemostasis, erythrocytes (by dielectrophoresis). In patients with hypertension, as the risk of venous thromboembolic complications increased, acceleration of leukocyte-platelet aggregation, increased fibrinogen level and decreased activity of XII-dependent fibrinolysis, which creates prerequisites for rheological disturbances, were revealed. The most accurate prediction of result according to severity of hemorheological disorders (differentiation moderate and expressed disorders from the lungs) is provided by such indicators of electric and viscoelastic parameters of erythrocytes, as the polarizability of red blood cells at a frequency of 106 Hz (AUC = 0,750 in), the speed of movement of cells to the electrodes (AUC = 0,746), deformation degree at a frequency of 5 × 105 Hz (AUC = 0,733), conductivity cell (AUC = 0,730), the generalized viscosity (AUC = 0,729), the index of aggregation of erythrocytes (AUC = 0,716), graduation according to the degree of strain at all frequencies (AUC = 0,716), generalized stiffness (AUC = 0,714), the deformation amplitude at frequency of 106 Hz (AUC = 0,711), the capacity of the cells (AUC = 0,693). The measure of specificity for different indices of erythrocytes is 75.4–99,3 % and a sensitivity of 84.1–98.6 %.Conclusions. The study of the parameters of hemostasis, markers of inflammation, red blood cells allowed us to determine the key indicators for assessing the severity of hemorheological disorders in patients with arterial hypertension. The work was carried out within the framework of the budgetary theme under the State Assignment No. 121090800102-4.

Accuracy and Long-Term Stability Assessment of Inductive Conductivity Cell Measurements on Argo Floats

This study demonstrates the long-term stability of salinity measurements from Argo floats equipped with inductive conductivity cells, which have extended float lifetimes as compared to electrode-type cells. New Argo float sensor payloads must meet the demands of the Argo governance committees before they are implemented globally. Currently, the use of CTDs with inductive cells designed and manufactured by RBR, Ltd., has been approved as a Global Argo Pilot. One requirement for new sensors is to demonstrate stable measurements over the lifetime of a float. To demonstrate this, data from four Argo floats in the western Pacific Ocean equipped with the RBRargo CTD sensor package are analyzed using the same Owens–Wong–Cabanes (OWC) method and reference datasets as the Argo delayed-mode quality control (DMQC) operators. When run with default settings against the standard DMQC Argo and CTD databases, the OWC analysis reveals no drift in any of the four RBRargo datasets and, in one case, an offset exceeding the Argo target salinity limits. Being a statistical tool, the OWC method cannot strictly determine whether deviations in salinity measurements with respect to a reference hydrographic product (e.g., climatologies) are caused by oceanographic variability or sensor problems. So, this study furthermore investigates anomalous salinity measurements observed when compared with a reference product and demonstrates that anomalous values tend to occur in regions with a high degree of variability and can be better explained by imperfect reference data rather than sensor drift. This study concludes that the RBR inductive cell is a viable option for salinity measurements as part of the Argo program.

Challenges of Measuring Abyssal Temperature and Salinity at the Kuroshio Extension Observatory

The deep ocean is severely undersampled. Whereas shipboard measurements provide irregular spatial and temporal records, moored records establish deep ocean high-resolution time series, but only at limited locations. Here, highlights and challenges of measuring abyssal temperature and salinity on the Kuroshio Extension Observatory (KEO) mooring (32.3°N, 144.6°E) from 2013 to 2019 are described. Using alternating SeaBird 37-SMP instruments on annual deployments, an apparent fresh drift of 0.03–0.06 psu was observed, with each newly deployed sensor returning to historical norms near 34.685 psu. Recurrent salinity discontinuities were pronounced between the termination of each deployment and the initiation of the next, yet consistent pre- and postdeployment calibrations suggested the freshening was “real.” Because abyssal salinities do not vary by 0.03–0.06 psu between deployment locations, the contradictory salinities during mooring overlap pointed toward a sensor issue that self-corrects prior to postcalibration. A persistent nepheloid layer, unique to KEO and characterized by murky, sediment-filled water, is likely responsible for sediment accretion in the conductivity cell. As sediment (or biofouling) increasingly clogs the instrument, salinity drifts toward a fresh bias. During ascent, the cell is flushed, clearing the clogged instrument. In contrast to salinity, deep ocean temperatures appear to increase from 2013 to 2017 by 0.0059°C, whereas a comparison with historical deep temperature measurements does not support a secular temperature increase in the region. It is suggested that decadal or interannual variability associated with the Kuroshio Extension may have an imprint on deep temperatures. Recommendations are discussed for future abyssal temperature and salinity measurements.

Fabrication of Thermal Conductivity Detector Based on MEMS for Monitoring Dissolved Gases in Power Transformer

In this work, a high sensitivity micro-thermal conductivity detector (μTCD) with four thermal conductivity cells was proposed. Compared with conventional TCD sensors, the thermal conductivity cell in this work was designed as a streamlined structure; the thermistors were supported by a strong cantilever beam and suspended in the center of the thermal conductivity cell, which was able to greatly reduce the dead volume of the thermal conductivity cell and the heat loss of the substrate, improving the detection sensitivity. The experimental results demonstrated that the μTCD shows good stability and high sensitivity, which could rapidly detect light gases with a detection limit of 10 ppm and a quantitative repeatability of less than 1.1%.

Thermal Shock Response of Yeast Cells Characterised by Dielectrophoresis Force Measurement

Dielectrophoresis is an electric force experienced by particles subjected to non-uniform electric fields. Recently, several technologies have been developed focused on the use of dielectrophoretic force (DEP) to manipulate and detect cells. On the other hand, there is no such great development in the field of DEP-based cell discrimination methods. Despite the demand for methods to differentiate biological cell states, most DEP developed methods have been focused on differentiation through geometric parameters. The novelty of the present work relies upon the point that a DEP force cell measurement is used as a discrimination method, capable of detecting heat killed yeast cells from the alive ones. Thermal treatment is used as an example of different biological state of cells. It comes from the fact that biological properties have their reflection in the electric properties of the particle, in this case a yeast cell. To demonstrate such capability of the method, 279 heat-killed cells were measured and compared with alive cells data from the literature. For each cell, six speeds were taken at different points in its trajectory inside a variable non-uniform electric field. The electric parameters in cell wall conductivity, cell membrane conductivity, cell membrane permittivity of the yeast cell from bibliography explains the DEP experimental force measured. Finally, alive and heat-treated cells were distinguished based on that measure. Our results can be explained through the well-known damage of cell structure characteristics of heat-killed cells.