Nonlinear behavioral models of HEMTs using response surface methodology

In this paper, the response surface methodology is proposed to model nonlinear microwave devices using different sampling techniques. Each of the methods represents a distinct approach: exploration-oriented (Voronoi tessellation), nonlinearity-exploitation-oriented (LOcal Linear Approximation) and model-error-minimization-oriented. This allows to build accurate and compact global behavioral models of drain voltage at different harmonics of a 0.15 mu m GaAs HEMT transistor with only few hundreds of samples. After choosing the best sampling technique, two types of global models are compared: Radial Basis Function and Kriging. It is shown that the modeling convergence depends on the model type, and better results are obtained using the Kriging model

Cardiac Surgery is Associated with Biomarker Evidence of Neuronal Damage

BACKGROUND: Anesthesia and surgery is commonly associated with central nervous system sequelae and cognitive symptoms, which may be caused by neuronal injury. Neuronal injury can be monitored by plasma concentrations of the neuronal biomarkers tau and neurofilament light protein (NFL). Currently, there are no studies examining whether neuronal injury varies between surgical procedures. OBJECTIVE: Our aim was to investigate if neuronal damage is more frequent after cardiac than after otolaryngeal surgery, as estimated by tau and NFL concentrations in plasma. METHODS: Blood samples were drawn before, during, and after surgery and concentrations of tau, NFL, Aβ40, and Aβ42 were measured in 25 patients undergoing cardiac surgery (9 off-pump and 16 on-pump) and 26 patients undergoing otolaryngeal surgery. RESULTS: Tau increased during surgery (1752%, p = 0.0001) and NFL rose seven days post-surgery (1090%, p < 0.0001) in patients undergoing cardiac surgery; even more in patients on-pump than off-pump. No changes were observed in patients undergoing otolaryngeal surgery and only minor fluctuations were observed for Aβ40 and Aβ42. CONCLUSION: Cardiac surgery is associated with neuronal injury, which is aggravated by extracorporeal circulation. Analyses of NFL and tau in blood may guide development of surgical procedures to minimize neuronal damage, and may also be used in longitudinal clinical studies to assess the relationship of surgery with future neurocognitive impairment or dementia

Planning of New Products Technological Mastering and its Influence on Economic Indicators of Companies

Improving the quality of services or improve product quality at the modern stage of economic development is one of the most important factors in the growth of production efficiency. The quality of products or services is essential to “stay afloat” and an important factor towards success in the market in conditions of tough competition. In the conditions of market relations in various companies and organizations the relevance of quality management is characterized by its focus on the formation of such level of quality products and services, which can absolutely meet all the needs of consumers. Maintaining the high quality of services and products is the main component that determines their competitiveness. Without consistency of quality, which meets the requirements of consumers in the market, it becomes impossible to integrate the national economy into the global economic management and to take in it high. A stable increase in the quality of products by enterprises is regarded currently as the main condition of its competitiveness on internal and foreign markets. The competitiveness of products or services largely determines the status of the country and is a fundamental factor of increasing its national wealth. Keywords: competitiveness, planning, technological development, investment costs, product quality, economic performance, R&D JEL Classifications: O14, O21, O32, O3

Increased percentage of L-selectin+ and ICAM-1+ peripheral blood CD4+/CD8+ T cells in active Graves' ophthalmopathy.

The purpose of the study was to evaluate the percentage of CD4+/CD8+ peripheral T cells expressing CD62L+ and CD54+ in patients with Graves' disease and to assess if these estimations could be helpful as markers of active ophthalmopathy. The study was carried out in 25 patients with Graves' disease (GD) divided into 3 groups: 1/ 8 patients with active Graves' ophthalmopathy (GO) (CAS 3-6, GO complaints pound 1 year), 2/ 9 patients with hyperthyroid GD without symptoms of ophthalmopathy (GDtox) and 3/ 8 patients with euthyroid GD with no GO symptoms (GDeu). The control group consisted of 15 healthy volunteers age and sex matched to groups 1-3. The expression of lymphocyte adhesion molecules was evaluated by using three-color flow cytometry. In GO group the percentage of CD8+CD54+, CD8+CD62L+, CD4+CD54+ and CD4+CD62L+ T cells was significantly higher as compared to controls (p&lt;0.001, p&lt;0.05, p&lt;0.01, p&lt;0.001 respectively). The percentage of CD8+CD54+ T lymphocytes was also elevated in GO group in comparison to hyperthyroid GD patients (p&lt; 0.05). CD4+CD62L+ and CD8+CD54+ percentages were also increased in GDtox and GDeu as compared to controls. We found a positive correlation between the TSHRab concentration and the percentage of CD8+CD62L+ T cells in all studied groups (r= 0.39, p&lt;0.05) and between the TSHRab level and CAS (r= 0.77, p&lt;0.05). The increased percentage of CD8+CD54+ and CD8+CD62L+ T cells in patients with Graves' ophthalmopathy may be used as a marker of immune inflammation activity

Global patterns and drivers of ecosystem functioning in rivers and riparian zones

River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth's biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented "next-generation biomonitoring" by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale.peerReviewe

A measurement setup for digital predistortion using direct RF undersampling

This work presents a measurement setup for digital predistortion which utilizes single channel direct RF undersam-pling, removing the need for mixer-based analog downconversion. The setup is tested on a commercial power amplifier, with a 10 MHz QPSK-modulated input signal, yielding an improvement in normalized mean square error from 0.0087 to 4.54e-04