1,188 research outputs found
Dissipative quantum metrology in manybody systems of identical particles
No full textEstimation of physical parameters is essential in almost any part of science and technology. The enhancement of performance in this task (e.g. beating the standard classical shot-noise limit) using available physical resources is a major goal in metrology. Quantum metrology in closed systems has indicated that entanglement in such systems may be a useful resource. However, whether in open quantum systems such enhancements may still show up is not yet fully understood. Here, we consider a dissipative (open) quantum system of identical particles in which a parameter of the open dynamics itself is to be estimated. We employ a recently developed dissipative quantum metrology framework, and investigate whether the entanglement produced in the course of the dissipative dynamics may help the estimation task. Specifically, we show that, even in a Markovian dynamics in which states become less distinguishable in time, at small enough times the entanglement generated by the dynamics may offer some advantage over the classical shot-noise limit
Investigation of the Effect of Aging on Health Costs: A Systematic Review
No full textBackground & Objectives: Aging and the need for more health care in the elderly population have incurred large expenditures. Based on the importance of the aging population phenomenon and the increase in lifetime in recent decades, this study aimed to systematically review the studies on costs of elderly health care.
Methods: In this systematic review, the articles published in PubMed Google Scholar, Science Direct, Scopus, and Ovid Medline databases from 2000 to 2017 were derived using a systematic search strategy.
Results: The results of the reviewed studies showed that by increasing the consumption of long-term care and home care, the costs would increase and by reducing the consumption of acute hospital care, such costs would decrease. Based on the results, the average cost of elderly health care in the reviewed studies was 48101 US dollars in 2015. Moreover, the highest average costs were for inpatient services (19003US dollars) and long-term care and home care (12583US dollars).
Conclusion: Considering the high costs of hospitalization of the elderly, measures like establishment of day care centers and home care instead of hospitalization should be taken into consideration in the elderly health care programs to reduce the number of hospitalizations.
Key¬words: Aging, the Elderly, Health Costs, Hospital Costs, Systematic Review
Citation: Rezapour A, Arabloo J, Alipour V, Alipour S. Investigation of the Effect of Aging on Health Costs: A Systematic Review. Journal of Health Based Research 2020; 5(4): 411-22. [In Persian
Screening of 20 species from Lamiaceae family based on phytochemical analysis, antioxidant activity and HPLC profiling
No full textThe Lamiaceae family encompasses numerous species highly valued for their applications in medicine, food, and cosmetics. In order to screen the Lamiaceae family and discover new sources of phytochemicals and antioxidants, we comprehensively evaluated 20 species from this family, including Phlomis herba-venti, P. tuberosa, P. olivieri, P. kurdica, Nepeta sp., N. cataria, N. saccharata, Stachys sp., S. inflata, Scutellaria albida, Marrubium parviflora, Mentha pulegium, Thymus kotschyanus, Lamium album, Salvia officinalis, S. multicaulis, S. macrochlamys, S. candidissima, S. verticillata, and S. nemorosa. The aerial parts of these species were analyzed to determine their total phenolic (TPC) and flavonoid (TFC) contents, total tannin content (TTC), ascorbic acid content (AAC), antioxidant capacity (assessed by FRAP and DPPH assays), and polyphenolic components (by HPLC). The phytochemical compounds and antioxidant properties varied widely among different species. The highest concentrations of TPC (70.93 mg GAE/g DW), TFC (17.89 mg Que/g DW), TTC (6.49 mg TAE/100 g), and AAC (1.15 mg AA/g DW), as well as the greatest antioxidant activity, were observed in different Salvia species. Additionally, chlorogenic and rosmarinic acids were the primary phenolic compounds identified in the extracts from the investigated Lamiaceae family. According to Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA), three groups of species were identified, characterized by variations in phytochemical composition and antioxidant capacity. The results obtained can provide new natural sources of phytochemicals and antioxidant agents, particularly from Salvia species, for the advancement of new products in the food, agricultural, cosmetics and health industries
A hybrid Pt/NbO/CNTs catalyst with high activity and durability for oxygen reduction reaction in PEMFC
No full textTo improve the kinetics and durability of Pt-based electrodes toward the oxygen reduction reaction (ORR), high electroactive and stable catalysts were synthesized by depositing Pt over niobium oxide (NbO) supported on commercial multi-wall carbon nanotubes (CNTs). The Pt/NbO/CNTs, exhibits excellent electroactivity and stability toward ORR, reaching a high electroactivity of 57 mA mgPt−1, higher than the Pt/CNTs and commercial Pt/C (20% Pt/C HiSPECTM). Moreover, the developed Pt/NbO/CNTs demonstrated outstanding durability under accelerated stress testing (AST) according to load cycling and startup/shutdown stability protocols. Proton exchange membrane fuel cells (PEMFC) tests with an MEA fabricated using Pt/NbO/CNTs showed excellent performance, with a low Pt loading down to 0.15 mg cm−2, achieving a maximum power density of 772 mW cm−2. Furthermore, a short-term durability test in PEMFC demonstrated only a 4% loss on the maximum power density at 80 °C. The superior electrocatalytic activity and durability of Pt/NbO/CNTs can be ascribed to the anchoring effect of Pt nanoparticles over the NbO/CNTs hybrid support, showing that the developed Pt/NbO/CNTs is a promising durable electrocatalyst for PEMFC applications
Long non-axisymmetric fibres in turbulent channel flow
No full textIn this work, we investigate the dynamics of long non-axisymmetric fibres in turbulent channel flow. The experimental facility is the TU Wien Turbulent Water Channel, consisting of a closed water channel (aspect ratio of 10), and the experiments are performed at a shear Reynolds number of 360. Fibres are neutrally buoyant rods that are curved and characterised by a length-to-diameter ratio of 120. Illumination is provided by a laser sheet and the motion of fibres is recorded by four high-speed cameras in a fully developed flow section. We apply multiplicative algebraic reconstruction techniques to the recorded images from four high-speed cameras to identify the three-dimensional location, shape and orientation of the fibres. The fibres are also tracked in time to obtain their three-dimensional vectors of velocity and rotation rate. We investigate the behaviour of the fibres, from the near-wall region to the channel centre, and we produce original statistics on the effect of curvature of the fibres on their orientation and rotation rate. Specifically, we measured the orientation and rotation rate of the fibres, and we can confirm that in the centre, the most homogeneous part of the channel, statistics, although influenced by the curvature, bear similarities to those obtained in previous investigations in homogeneous isotropic turbulence. In addition, we have been able to compare the tumbling rate of our long non-axisymmetric fibres with previous solutions for curved ellipsoids in simple shear flow
Entropy production and non-Markovian dynamical maps
No full textIn the weak-coupling limit approach to open quantum systems, the presence of the bath is eliminated and accounted for by a master equation that introduces dissipative contributions to the system reduced dynamics: within this framework, there are no bath entropy contributions to the entropy balance. We show that, as a consequence, the entropy production fails to be positive for a class of physically legitimate, that is completely positive and trace preserving, non-Markovian dynamical maps. Moreover, in absence of the semigroup property, if the reduced dynamics has a thermal asymptotic state, this need not be stationary. Then even the integrated entropy production becomes negative. These observations imply that, when the conditions leading to reduced dynamics of semigroup type are relaxed, a consistent formulation of the second law of thermodynamics requires that the environment contribution to the entropy balance be explicitly taken into account
Internal Model Control of Cycloid Trajectory for Video-Rate AFM Imaging with a SOI-MEMS Nanopositioner
No full textWe demonstrate high-performance tracking of a cycloid trajectory for video-rate atomic force microscopy imaging by employing internal model control. To acquire sequential images using cycloid scanning, the stage needs to follow a slow periodic triangular wave superimposed on a sinusoidal signal along one axis with the remaining axis tracking a purely sinusoidal signal. The sharp turnarounds in the triangular signal result in a large tracking error. We utilize a trapezoidal signal to address this issue. To obtain high-precision positioning, the controller comprises the internal model of harmonic waveforms and the ramp signal plus additional integrator to compensate for stage nonlinearities. The controller is implemented on a two degree of freedom microelectromechanical system nanopositioner and operated at scan frequencies ranging from 500 Hz to 2580 Hz in a window size of 5 µm by 10 µm. While the pitch size of the trajectory is set to be 46 nm, the RMS value of tracking error remains below 7 nm. The highest scan rate of 20 frames per second is achieved at f =2580 Hz with the maximum transient tracking error of 15 nm.Erik Jonsson School of Engineering and Computer Scienc
Highly active platinum supported Mo-doped titanium nanotubes suboxide (Pt/TNTS-Mo) electrocatalyst for oxygen reduction reaction in PEMFC
No full textIn this study, an innovative carbon-free electrocatalyst for oxygen reduction reaction was synthesized depositing platinum on titanium nanotube suboxide (trititanium pentoxide nanotubes, TNTS) obtained from titania doped with molybdenum (Pt/TNTS-Mo). The TNTS-Mo support was synthesized in autoclave, while the Pt/TNTS-Mo using the polyol method. The carbon-free support and the Pt-based catalyst were fully characterized via rotating disk electrode (RDE) technique and polymer exchange membrane fuel cell (PEMFC) station by preparing a membrane electrode assembly (MEA) with Nafion® 115, loaded with 0.35 mgPt cm−2 of Pt/TNTS-Mo at the cathode, and 0.35 mgPt cm−2 of commercial Pt/C (E-TEK) at the anode. In RDE experiments, the Pt/TNTS-Mo exhibited low overpotential and remarkable electroactivity toward oxygen reduction reaction (ORR: mass activity of 110.7 mA mgPt−1 at 0.9 V vs SHE). Moreover, the Pt/TNTS-Mo demonstrated excellent stability. Tests in a 25 cm2 single cell PEMFC resulted to maximum power density of 0.52 Wcm−2
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