In this paper, we describe and present a Virtual Instrument, a tool that allows the determination of the electromechanical, dielectric, and elastic coefficients in polarised ferroelectric ceramic ...discs (piezoceramics) in the linear range, including all of the losses when the piezoceramics are vibrating in radial mode. There is no evidence in the recent scientific literature of any automatic system conceived and implemented as a Virtual Instrument based on an iterative algorithm issued as an alternative to solve the limitations of the ANSI IEEE 176 standard for the characterisation of piezoelectric coefficients of thin discs in resonant mode. The characterisation of these coefficients is needed for the design of ultrasonic sensors and generators. In 1995, two of the authors of this work, together with other authors, published an iterative procedure that allowed for the automatic determination of the complex constants for lossy piezoelectric materials in radial mode. As described in this work, the procedures involved in using a Virtual Instrument have been improved: the response time for the characterisation of a piezoelectric sample is shorter (approximately 5 s); the accuracy in measurement and, therefore, in the estimates of the coefficients has been increased; the calculation speed has been increased; an intuitive, simple, and friendly user interface has been designed, and tools have been provided for exporting and inspecting the measured and processed data. No Virtual Instrument has been found in the recent scientific literature that has improved on the iterative procedure designed in 1995. This Virtual Instrument is based on the measurement of a unique magnitude, the electrical admittance (Y = G + iB) in the frequency range of interest. After measuring the electrical admittance, estimates of the set of piezoelectric coefficients of the device are obtained. The programming language used in the construction of the Virtual Instrument is LabVIEW 2019®.
Background The Atellica Solution comprises chemistry (CH) and immunoassay (IM) analyzers. Recently, six early adopter clinical laboratories across Europe evaluated the analytical performance of 20 CH ...and IM assays. To measure analytical performance quality, Sigma metrics were calculated for individual-site and pooled-site results. Methods Precision, detection capability, linearity, and method comparison studies were performed according to Clinical Laboratory Standards Institute protocols. Global Sigma metrics across sites were calculated from pooled data at the medical decision level using total allowable error (TEa) goals from CLIA for CH assays, and TEa goals from RiliBÄK for IM assays; and, the equation: Sigma metrics=%TEa-%bias/%CV. A pooled %CV was calculated by combining the imprecision obtained from individual sites. Bias calculations were performed against the ADVIA Chemistry system or ADVIA Centaur system using Deming regression analysis (Passing-Bablok regression for electrolytes) on the pooled-site data. The 103 individual-site Sigma metric calculations used individual-site imprecision and pooled-bias. Results The limits of blank and detection results agreed with the manufacturer's claims. Most assays were linear across the assay range tested. Pooled Sigma metrics were good or better (>4 Sigma) for 18 of 20 assays; and, acceptable for urea nitrogen (3.1) and sodium (3.9), the latter values attributable to higher imprecision at one of five sites. Conclusions Sigma metrics for data generated across multiple real-world sites evaluating the Atellica Solution demonstrated good or better performance of greater than 4 Sigma for 18 of 20 assays tested. Overall, results verified the manufacturer's claims that methods were fit for use in clinical laboratories.
This paper describes a virtual instrument capable of the automatic and quasi-instantaneous classification of a vehicle according to category when it is driving along the road. The vehicle’s ...classification is based on accurate measurements of both the vehicle’s speed and its wheelbase. Our research is focused on achieving accurate speed and wheelbase measurements and then determining the category of the vehicle through the developed software. The vehicle categorization is based on the wheelbase measurements and the number of axles and metal masses of the vehicle. The system has a complementary magnetic sensor, which helps in classifying the vehicle when the wheelbase measurement could be representative of different categories, and a camera to confirm the results of the experiment. The proposed measurement system presents a novel method for classifying vehicles according to type using piezoelectric transducers (piezo sensors). In addition, no system references have been found that encompass the functionalities of the presented system based on the information of only two piezoelectric transducers. The system has important advantages over current alternatives (systems based on inductive loops, cameras, fiber optic sensors or lasers), the installation is simple and non-invasive and with a success rate of the classification greater than 90%. The system consists of a signal acquisition point on the pavement, signal conditioning hardware and a data acquisition (DAQ) module, which links the hardware and the virtual instrument developed in LabVIEW®. Finally, the system has been tested on the road with real traffic, and the experimental results are presented and discussed in this paper.
The Fourth Universal Definition of Myocardial Infarction Global Taskforce recommends the use of high sensitive troponin (hs-Tn) assays in the diagnosis of acute myocardial infarction. We evaluated ...the analytical performance of the Atellica IM High-sensitivity Troponin I Assay (hs-TnI) (Siemens Healthcare Diagnostics Inc., Tarrytown, USA) and compared its performance to other hs-TnI assays (Siemens Advia Centaur, Dimension Vista, Dimension EXL, and Abbott Architect (Wiesbaden, Germany)) at one or more sites across Europe.
Precision, detection limit, linearity, method comparison, and interference studies were performed according to Clinical and Laboratory Standards Institute protocols. Values in 40 healthy individuals were compared to the manufacturer’s cut-offs. Sample turnaround time (TAT) was examined.
Imprecision repeatability CVs were 1.1–4.7% and within-lab imprecision were 1.8–7.6% (10.0–25,000 ng/L). The limit of blank (LoB), detection (LoD), and quantitation (LoQ) aligned with the manufacturer’s values of 0.5 ng/L, 1.6 ng/L, and 2.5 ng/L, respectively. Passing-Bablok regression demonstrated good correlations between Atellica IM analyser with other systems; some minor deviations were observed. All results in healthy volunteers fell below the 99th percentile URL, and greater than 50% of each sex demonstrated values above the LoD. No interference was observed for biotin (≤ 1500 µg/L), but a slight bias at 5.0 g/L haemoglobin and 50 ng/L Tn was observed. TAT from was fast (mean time = 10.9 minutes) and reproducible (6%CV).
Real-world analytical and TAT performance of the hs-TnI assay on the Atellica IM analyser make this assay fit for routine use in clinical laboratories.
DHX15 is a downstream substrate for Akt1, which is involved in key cellular processes affecting vascular biology. Here, we explored the vascular regulatory function of DHX15. Homozygous DHX15 gene ...deficiency was lethal in mouse and zebrafish embryos. DHX15
zebrafish also showed downregulation of VEGF-C and reduced formation of lymphatic structures during development. DHX15
mice depicted lower vascular density and impaired lymphatic function postnatally. RNAseq and proteome analysis of DHX15 silenced endothelial cells revealed differential expression of genes involved in the metabolism of ATP biosynthesis. The validation of these results demonstrated a lower activity of the Complex I in the mitochondrial membrane of endothelial cells, resulting in lower intracellular ATP production and lower oxygen consumption. After injection of syngeneic LLC1 tumor cells, DHX15
mice showed partially inhibited primary tumor growth and reduced lung metastasis. Our results revealed an important role of DHX15 in vascular physiology and pave a new way to explore its potential use as a therapeutical target for metastasis treatment.
Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide, ranging from steatosis to non-alcoholic steatohepatitis (NASH). Recently, cerium oxide ...nanoparticles (CeO
NPs) have emerged as a new antioxidant agent with hepatoprotective properties in experimental liver disease. The aim of the current investigation was to elucidate whether CeO
NPs display beneficial effects in an experimental model of NAFLD.Therefore, fifteen Wistar rats were subjected to a methionine and choline deficient diet (MCDD) for 6 weeks and intravenously treated with CeO
NP or vehicle during the weeks three and four of the diet. The effect of CeO
NPs on serum biochemistry, hepatic steatosis, inflammation, fatty acid content and expression of reactive oxygen species (ROS) and lipid metabolism related genes was assessed. MCDD fed rats showed increased inflammation, enhanced hepatic lipid accumulation of both saturated and unsaturated fatty acids (FAs) and overexpression of genes related to fatty liver and ROS metabolism. Treatment with CeO
NPs was able to reduce the size and content of hepatocyte lipid droplets, the hepatic concentration of triglyceride- and cholesterol ester-derived FAs and the expression of several genes involved in cytokine, adipokine and chemokine signaling pathways. These findings suggest that CeO
NPs could be of beneficial value in NAFLD.
Blood flow (Qb) is one of the dialysis parameters most strongly influencing the performance of dialysis modalities. However, few studies have compared different dialysis modalities in patients with ...low Qb. We conducted a prospective, single‐center study in 21 patients. Each patient underwent four dialysis sessions with routine dialysis parameters: high‐flux hemodialysis (HD), predilution hemodiafiltration (pre‐HDF), expanded HD (HDx), and postdilution HDF (post‐HDF). The removal ratios (RR) of urea, creatinine, ß2‐microglobulin, myoglobin, prolactin, α1‐microglobulin, free kappa and lambda immunoglobulin light chains (ķFLC and λFLC), α1‐acid glycoprotein, and albumin were compared intraindividually. A proportional part of the dialysate was collected to quantify albumin loss. There were no differences in urea and creatinine RRs. The β2‐microglobulin RR was higher in pre‐HDF and post‐HDF. Myoglobin and prolactin RRs were higher with HDx and post‐HDF. The α1‐microglobulin and α1‐acid glycoprotein RRs were significantly higher with post‐HDF than with other treatments, and RRs obtained with HDx were higher than obtained with HD and pre‐HDF. Free ķFLC and λFLC RRs showed the following results in ascending order: HD, pre‐HDF, HDx, and post‐HDF, most of them with statistical significance. Albumin loss varied from 0.45 g with HD to 3.5 g with post‐HDF. The global removal score values were 41.0 ± 4.8% with HD, 44.0 ± 5.2% with pre‐HDF, 49.5 ± 4.6% with HDx, and 54.8 ± 5.3% with post‐HDF, with significant differences between all treatment modalities. In conclusion, this study confirms the superiority of post‐HDF over high‐flux HD, pre‐HDF, and HDx in patients with low Qb. HDx was the closest alternative to post‐HDF and was clearly superior to HD and pre‐HDF. Finally, pre‐HDF was also superior to HD. With this Qb, there was a higher risk of underdialysis, both diffusive and convective, especially in patients with a session duration of less than 5 h.
Patients and rats with cirrhosis and ascites have portal hypertension and circulatory dysfunction. Synthetic arginine vasopressin (AVP) receptor agonists able to induce systemic and mesenteric ...vasoconstriction have shown their usefulness in reducing portal pressure (PP) in this condition. We assessed the potential therapeutic value of a new V1a‐AVP receptor partial agonist with a preferential splanchnic vasoconstrictor effect (FE 204038) in rats with cirrhosis and ascites. The hemodynamic effects of cumulative intravenous doses of FE 204038, terlipressin, or vehicle were investigated. Mean arterial pressure and PP were continuously recorded and cardiac output and systemic vascular resistance (SVR) assessed at 30‐minute intervals for 90 minutes. Urine volume, urine osmolality, and urinary excretion of sodium and creatinine were measured in basal conditions and following twice‐daily subcutaneous doses of FE 204038 or vehicle. PP, mean arterial pressure, cardiac output, SVR, and ascites volume were also measured after 6 days. The expression of an array of vasoactive genes was assessed in the thoracic aorta and the mesenteric circulation of control rats and rats with cirrhosis and ascites. FE 204038 dose‐dependently decreased PP, did not modify mean arterial pressure, and increased SVR. The effect of the V1a‐AVP receptor partial agonist on PP was associated with an improvement in urine volume and urinary excretion of sodium during the first day of treatment. SVR was higher and cardiac output and ascites volume were lower in rats with cirrhosis and ascites treated with FE 204038. V1a‐AVP receptor expression in rats with cirrhosis and ascites was markedly enhanced in the mesenteric circulation compared to the thoracic aorta. Conclusion: FE 204038 increases sodium excretion and reduces portal hypertension and ascites in experimental cirrhosis. V1a‐AVP receptor partial agonism could be a useful pharmacological treatment in decompensated patients with cirrhosis. (Hepatology 2016;63:207–216)
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