Search results for "dynamic"
showing 10 items of 12329 documents
Microalbuminuria fractional clearance and early renal permselectivity changes in essential hypertension.
1992
In order to verify if, in essential hypertension (EH), the microalbuminuria (AER) increase could be due to hemodynamic modifications or to glomerular structural changes, in 15 essential hypertensives (EHs) with 24-hour AER16 micrograms/min and in 15 EHs with 24-hour AERor = 16 micrograms/min, the day- and nighttime behavior of creatinine clearance (Ccr), as well as AER clearance (AER-C) and fractional clearance (AER-FC), and behavior of blood pressure (BP) was evaluated. Patients with 24-hour AER16 micrograms/min showed significantly higher values of 24-hour and daytime Ccr than the other group of EHs, while during the night period, there were no significant differences between the two grou…
Targeted Hybrid Nanocarriers as a System Enhancing the Skin Structure
2021
The skin is constantly exposed to external and internal factors that disturb its function. In this work, two nanosystems-levan nanoparticles and a surfactin-stabilized nanoemulsion were preserved (tested for microbial growth) and characterized (size, polydispersity, Zeta potential, and stability). The nanosystems were introduced in the model formulations-cream, tonic, and gel, and confirmed by TEM. The analysis showed that nanoemulsion has a spherical morphology and size 220–300 nm, while levan nanoparticles had irregular shapes independently of the use of matrix and with particle size (130–260 nm). Additionally, we examined the antiradical effect of levan nanoparticles and nanoemulsion in …
Numerical approach to problems of gravitational instability of geostructures with advected material boundaries
1998
SUMMARY We present a numerical approach for solving 2-D mantle flow problems where the chemical composition changes abruptly across intermediate boundaries. The method combines a Galerkin-spline technique with a method of integration over regions bounded by advected interfaces to represent discontinuous variations of material parameters. It allows direct approximation of a natural free surface position, instead of a posteriori calculation of topography from the normal stress at the upper free-slip boundary. We formulate a model where a viscous incompressible fluid filling a square box is divided into layers (not necessarily horizontal) by advected boundaries, across which the density and vi…
Aerodynamics of Ski Jumping
2016
Ski jumping is an exciting and primarily competitive sport involving both ballistic and aerodynamic factors. The ballistic factors are release velocity and release position of a ski jumper from the take-off table, whereas aerodynamic factors include the gliding properties of the jumper/ski system (velocity, suit design, surface area, posture of the jumper/ski system, resisting and lifting forces). Both ballistic and aerodynamic factors place special demands on the jumper so that he/she can, for example, optimally maximize the vertical lift and minimize the drag forces. Ski jumping has attracted spectators 200 years and it has undergone several notable steps in the development of performance…
Unconventional Aeronautical Investigatory Methods: The Case of Alitalia Flight AZ 112
2021
Viene svelato scientificamente la causa del disastro aereo di Montagna Longa del 5 maggio 1972 Based on unconventional air investigation techniques, this book highlights the mysterious crash of Alitalia flight AZ 112 on 5 May 1972, which killed 115 people, and was blamed solely on pilot negligence. Its findings show the cause of the disaster was not actually related to any pilot negligence, but, rather, it was the result of a criminal act. It argues that this attack was a symptom of the geopolitical tensions in Italy and Europe in that decade. Based on unconventional air investigation techniques, this book highlights the mysterious crash of Alitalia flight AZ 112 on 5 May 1972
Towards comprehensive non-target screening using heart-cut two-dimensional liquid chromatography for the analysis of organic atmospheric tracers in i…
2021
Abstract Non-target screening of secondary organic aerosol compounds in ice cores is used to reconstruct atmospheric conditions and sources and is a valuable tool to elucidate the chemical profiles of samples with the aim to obtain as much information as possible from one mass spectrometric measurement. The coupling of mass spectrometry to chromatography limits the results of a non-target screening to signals of compounds within a certain polarity range based on the utilized stationary phases of the columns. Comprehensive two-dimensional liquid chromatography (LCxLC) introduces a second column of different functionality to enable the analysis of a broader range of analytes. Conventional LCx…
Comparison of UV and charged aerosol detection approach in pharmaceutical analysis of statins
2009
Abstract CAD (charged aerosol detector) has recently become a new alternative detection system in HPLC. This detection approach was applied in a new HPLC method for the determination of three of the major statins used in clinical treatment—simvastatin, lovastatin and atorvastatin. The method was optimized and the influence of individual parameters on CAD response and sensitivity was carefully studied. Chromatography was performed on a Zorbax Eclipse XDB C18 (4.6 mm × 75 mm, 3.5 μm), using acetonitrile and formic acid 0.1% as mobile phase. The detection was performed using both CAD (20 pA range) and DAD (diode array detector—238 nm) simultaneously connected in series. In terms of linearity, …
TAKEOFF AND LANDING ROBUST CONTROL SYSTEM FOR A TANDEM CANARD UAV
2005
In spite of modern wide improvements in UAV’s technologies, a few number of such a vehicles is fully autonomous from takeoff to landing . So, either autonomous operation or operation with minimal human intervention is, actually, the primary design goal for the UAV’s researchers. The core of the problem is the design of the landing and takeoff control system. The objective of this paper is to design a control system in which the same state variables are controlled during both the descending/ascending path and the flare, tacking into account the actual ground effect. Robust control techniques are employed with the aim to cope with atmospheric turbulence, measurement noise, parameter variation…
MYCOTOXINS | Detection and Analysis by Classical Techniques
2014
This article is a revision of the previous edition article by Imad Ali Ahmed, volume 2, pp. 1526–1532, © 1999, Elsevier Ltd.
The Artificial Society Analytics Platform
2020
Author's accepted manuscript Social simulation routinely involves the construction of artificial societies and agents within such societies. Currently there is insufficient discussion of best practices regarding the construction process. This chapter introduces the artificial society analytics platform (ASAP) as a way to spark discussion of best practices. ASAP is designed to be an extensible architecture capable of functioning as the core of many different types of inquiries into social dynamics. Here we describe ASAP, focusing on design decisions in several key areas, thereby exposing our assumptions and reasoning to critical scrutiny, hoping for discussion that can advance debate over be…