Improvement of the fast impedance spectroscopy method using square pulse excitation

Published in: Proceedings of the 14th Joint International IMEKO TC1 + TC7 + TC 13 Symposium : "Intelligent quality measurements - theory, education and training" ; in conjunction with the 56th IWK, Ilmenau University of Technology and the 11th SpectroNet Collaboration Forum ; 31. August - 2. September 2011, JenTower Jena, Germany. - Ilmenau : Univ.-Bibliothek, ilmedia, 2011. URN: urn:nbn:de:gbv:ilm1-2011imeko:

Charakterystyki i obszary zastosowań telekomunikacyjnych usług multimedialnych. Telekomunikacja i Techniki Informacyjne, 2002, nr 1-2

Przedstawiono modele i omówiono charakterystyki funkcjonalne pięciu standaryzowanych kategorii telekomunikacyjnych usług multimedialnych, takich jak: wideotelefonia, wideotekst, interaktywna prezentacja audiowizualna, wideokonferencja i telekonferencja audiograficzna. Dla każdej z opisanych kategorii usług określono potencjalne obszary zastosowań, wskazano jej najbardziej popularne aplikacje i zaprezentowano prognozy zapotrzebowania na te aplikacje. Ponadto dla każdej z tych aplikacji podano wymagania dotyczące pasma i inne uwarunkowania sieciowe

Investigation of micromechanical properties and tribological behavior of WE43 magnesium alloy after deep cryogenic treatment combined with precipitation hardening

This study investigated the micromechanical and tribological properties of WE43 alloy (Mg-Y-Nd-Zr) alloy subjected to cryogenic treatment and precipitation hardening. Microindentation tests were carried out in the range of load from 100 to 1000 mN. The introduction of deep cryogenic treatment (DCT) was shown to increase hardness and Young’s modulus, and reduce the total indentation work. As the load set during the tests increased, a gradual decrease in the measured values was observed, indicating a significant relationship between the indent size and the value of the measured parameters. Cryogenic treatment used in conjunction with precipitation hardening (after solutioning and after aging) reduces the tribological wear of the alloy. Tests have shown an almost twofold reduction in the area of the wear trace and in the volumetric wear of the alloy, as well as a more than twofold reduction in linear wear, with relatively small fluctuations in the coefficient of friction. Abrasion was the main mechanism of wear. Areas where microcutting, adhesion and plastic deformation occurred were also observed. The results indicate the significant effectiveness of the applied heat treatment in improving the service life of the WE43 alloy containing rare earth metals

Relationship between renal resistive index and target organ damage in patiens with treated primary hypertension

Wstęp Celem pracy była ocena związku między wskaźnikiem oporu wewnątrznerkowego (RI) a wartościami ciśnienia tętniczego uzyskanymi w trakcie automatycznej całodobowej rejestracji ciśnienia i powikłaniami narządowymi u pacjentów z leczonym nadciśnieniem tętniczym pierwotnym. Materiał i metody W badaniu wzięło udział 220 osób: 125 chorych z leczonym nadciśnieniem tętniczym pierwotnym oraz 95 zdrowych osób z prawidłowym ciśnieniem - grupa kontrolna. U każdego pacjenta wykonano badania biochemiczne, całodobowy ambulatoryjny pomiar ciśnienia tętniczego oraz badanie dopplerowskie tętnic szyjnych i tętnic nerkowych i badanie echokardiograficzne. Wyniki Wartości RI w grupie nadciśnienia tętniczego były znamiennie wyższe w porównaniu z wartościami RI w grupie kontrolnej (0,63 &#177; 0,07 vs. 0,59 &#177; 0,05; p < 0,01); powyższa różnica była również znamienna po uwzględnieniu podziału pod względem płci. Również wartości wskaźnika pulsacji (PI) były istotnie wyższe w grupie nadciśnienia tętniczego w porównaniu z osobami z grupy kontrolnej (1,16 &#177; 0,26 vs. 1,05 &#177; 0,19; p < 0,01). W grupie nadciśnienia tętniczego w jednoczynnikowej liniowej analizie korelacji wykazano istotny związek między RI a wiekiem, wysokością ciśnienia tętna i ambulatoryjnego wskaźnika sztywności tętnic (AASI) oraz średnią wartością rozkurczowego ciśnienia z okresu doby, GFR, IMT, wskaźnikiem E/E&#8217; i RWT. W analizie wieloczynnikowej tylko korelacja między RI a IMT była niezależna statystycznie od innych zmiennych uwzględnionych w modelu. Wnioski Wyniki pracy wskazują na istnienie dodatniej korelacji RI z wczesnymi powikłaniami narządowymi nadciśnienia tętniczego, a zwłaszcza z IMT tętnicy szyjnej. Wykazano ponadto, że wartości RI są większe u pacjentów z leczonym hipotensyjnie nadciśnieniem tętniczym w porównaniu z grupą osób z prawidłowym ciśnieniem tętniczym.Background The objective of the study was to evaluate renal resistive index (RI) value in patients with treated hypertension in relation to ABPM values and target organ damage. Material and methods The study included two groups. Group 1 consisted of 125 patients aged 51.2 &#177; 12.2 with treated essential hypertension (EH), group 2 consisted of 95 normotensive, healthy subjects aged 37.9 &#177; 10.4. In both groups biochemical evaluations, ABPM, echocardiography, carotid and renal arteries ultrasound and Doppler studies were performed. Results RI values in patients with treated EH were significantly higher as compared to RI values in the normotensive, control group (0.63 &#177; 0,07 vs. 0.59 &#177; 0.05; p < 0.01). This difference was still significant after dividing according to the sex. PI values in EH group were also significantly higher as compared with control group. In an univariate analysis, in the hypertensive group, RI values correlated with age, PP and AASI values, mean 24-h diastolic blood pressure values, GFR, carotid IMT and with echocardiographic parameters: E/E&#8217; ratio and RWT. In the multivariate analysis, RI values correlated independently only with carotid IMT. Conclusions In our study renal resistive values were positively correlated with early target organ damage. The resistive index was higher in those with a long-standing treated hypertension as compared to normotensive subjects

Total arterial revascularization coronary artery bypass surgery in patients with atrial fibrillation

Background: Atrial fibrillation (AF) is a relatively common comorbidity among patients referred for coronary artery bypass grafting (CABG) associated with poorer prognosis. However, little is known about how surgical technique influences survival in this population.Aim: The aim of the current analysis was to determine whether total arterial revascularization (TAR) is associated with improved long-term outcomes in patients with preoperative AF.Methods: We analyzed patient’s data from a HEIST (HEart surgery In atrial fibrillation and Supraventricular Tachycardia) registry. The registry, to date, involves five tertiary high-volume centers in Poland. Between 2006 and 2019, 4746 patients presented with pre-operative AF and multivessel coronary artery disease and underwent CABG. We identified cases of TAR and used propensity score matching to determine non-TAR controls. Median follow-up was 4.1 years (IQR, 1.9–6.8).Results: Propensity matching resulted in 295 pairs of TAR vs. non-TAR. The mean (standard deviation [SD]) number of distal anastomoses was 2.5 (0.6) vs. 2.5 (0.6) (P = 0.94) respectively. Operative and 30-day mortality were not different between TAR and non-TAR patients (hazard ratio [HR] and 95% confidence intervals [CIs], 0.17 (0.02–1.38); P = 0.12 and 0.74 [0.40–1.35]; P = 0.33), respectively. On contrary, TAR was associated with a nearly 30% improved late survival: HR, 0.72 (0.55–0.93); P = 0.01. This benefit was sustained in subgroup analyses, yet most appraised in low-risk patients (&lt;70 years old; EuroSCORE II &lt;2; no diabetes) and when off-pump CABG was performed.Conclusions: TAR in patients with pre-operative AF is safe and associated with improved survival with particular survival benefit in younger low-risk patients undergoing off-pump CABG

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements