Use of a non-invasive electrocardiographic mapping system may aid in rapid diagnosis of atrial or ventricular arrhythmias or the detection of ventricular dyssynchrony. The aim of the present study ...was to validate the mapping accuracy of a novel non-invasive epi- and endocardial electrophysiology system (NEEES).
Patients underwent pre-procedural computed tomography or magnetic resonance imaging of the heart and torso. Radiographic data were merged with the data obtained from the NEEES during pacing from implanted pacemaker leads or pacing from endocardial sites using an electroanatomical mapping system (CARTO 3, Biosense Webster). The earliest activation as denoted on the NEEES three-dimensional heart model was compared with the true anatomic location of the tip of the pacemaker lead or the annotated pacing site on the CARTO 3 map. Twenty-nine patients mean age: 62 ± 11 years, 6/29 (11%) female, 21/29 (72%) with ischaemic cardiomyopathy were enrolled into the pacemaker verification group. The mean distance from the non-invasively predicted pacing site to the anatomic reference site was 10.8 ± 5.4 mm for the right atrium, 7.7 ± 5.8 mm for the right ventricle, and 7.9 ± 5.7 mm for the left ventricle activated via the coronary sinus lead. Five patients mean age 65 ± 4 years, 2 (33%) females underwent CARTO 3 verification study. The mean distance between non-invasively reconstructed pacing site and the reference pacing site was 7.4 ± 2.7 mm for the right atrium, 6.9 ± 2.3 mm for the left atrium, 6.5 ± 2.1 mm for the right ventricle, and 6.4 ± 2.2 for the left ventricle, respectively.
The novel NEEES was able to correctly identify the site of pacing from various endo- and epicardial sites with high accuracy.
The process of current collection with a non-autonomous power source used for electric motors of a rolling stock occurs in a contact pair: pantograph's skid (head) - contact wire. The main indicator ...of the quality of current collection is the contact pressure, which depends on many factors. The dominant factor is static pressure generated by spring mechanisms of the pantograph. The pressure is a result of dynamic and other random factors. It is difficult to keep it constant. One of the solutions for optimizing contact pressure can be a cable cam-spring mechanism installed in the lifting unit of the contact part of the pantograph. Due to the special cam shape, it is possible to stabilize forces of the contact insert. Static pressing does not depend on its altitude. Dynamic forces can be smoothed.
Recently, it has been paid more and more attention to the concept of sustainable development. One of these technologies is the production of "green concrete". It can be created by replacing natural ...concrete aggregate with secondary one. Therefore, white glass cullet was used as a replacement for 30% of coarse and fine aggregates in this study to design "green concrete". It was designed four concrete mixes for the investigation. Measurement of the fresh concrete mixes' performance showed that the use of glass aggregates reduces its workability. But it can be increased by using chemical admixtures. The highest strength - 28.94% more than the control sample, was obtained by a sample that contained coarse of glass aggregate and had low water-cement ratio. Sample №3 had lower strength only for 1.62% than sample №1 among mixtures with normal W/c ratio. Исследование фазовых превращений показало
New data on both total and differential cross sections of the production of η mesons in proton–deuteron fusion to He3η in the excess energy region 13.6MeV≤Qη≤80.9MeV are presented. These data have ...been obtained with the WASA-at-COSY detector setup located at the Forschungszentrum Jülich, using a proton beam at 15 different beam momenta between pp=1.60GeV/c and pp=1.74GeV/c. While significant structure of the total cross section is observed in the energy region 20MeV≲Qη≲60MeV, a previously reported sharp variation around Qη≈50MeV cannot be confirmed. Angular distributions show the typical forward-peaking that was noted earlier. For the first time, it is possible to study the development of these angular distributions with rising excess energy over a wide interval.
Ecological efficiency photocatalytic concrete Sopov, V P; Shyshko, N S; Kondrashchenko, V I ...
IOP conference series. Materials Science and Engineering,
08/2020, Letnik:
907, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The process of urbanization is accompanied by the formation of a high density of street highways, buildings, people, transport and industrial enterprises, high energy consumption, an increase in the ...amount of waste and the release of a large amount of pollutants into the atmosphere and the aquatic environment. Air pollution is one of the most serious environmental problems in cities and poses a threat to vegetation, animals, materials and human health. One of the main environmental pollutants is nitrogen oxides (NOx). Finding ways to remove NOx from the surrounding air is a necessity today, as it will help to improve the ecology of large cities, as well as reduce O3 concentration at ground level. Titanium Dioxide (TiO2) is a natural semiconductor material that is widely used in many industries. In construction, titanium dioxide is used to create building materials with a self-cleaning surface. In recent years, a fairly powerful photocatalytic effect of surfaces with titanium dioxide has been discovered. Self-cleaning combined with the photocatalytic effect of TiO2 makes it an ideal additive in the production of building materials for urban environments. Depending on the application, TiO2 can be used as a coating, additive in concrete, gypsum or paint. TiO2 can be used for surfaces of paving elements or building facades, retaining walls, tunnels. In this paper, we study the effect of the addition of titanium dioxide on the formation of the physicochemical properties of concrete.
The foundations of wind farms are massive structures that require temperature control of concrete hardening during their construction. This is due to the need to ensure crack resistance and specific ...operating conditions of engineering networks located in the body of the structure. The work describes a comprehensive study of the foundations construction on the Zaporizhzhya wind farm. The study included calorimetric analysis using adiabatic calorimetry and on-site temperature monitoring of the object using a continuous temperature measurement system. Laboratory studies allowed verify the composition of concrete proposed by the concrete manufacturer and develop recommendations for concreting. The data obtained showed that the hardening conditions approach adiabatic ones with a foundation slab thickness of more than 2.5 m. This leads to a temperature gradient of more than 25 ° C between the internal and external parts of the structure. The adopted recipe and technological solutions have ensured the achievement of acceptable conditions for the foundation slab construction in the winter.
In a given research using the example of traction network area with high asymmetry of power supply parameters, the sequence of comparative assessment of power losses in DC traction network with ...parallel and traditional separated operating modes of traction substation feeders was shown. Experimental measurements were carried out under these modes of operation. The calculation data results based on statistic processing showed the power losses decrease in contact network and the increase in feeders. The changes proved to be critical ones and this demonstrates the significance of potential effects when converting traction network areas into parallel feeder operation. An analytical method of calculation the average power losses for different feed schemes of the traction network was developed. On its basis, the dependences of the relative losses were obtained by varying the difference in feeder voltages. The calculation results showed unreasonableness transition to a two-sided feed scheme for the considered traction network area. A larger reduction in the total power loss can be obtained with a smaller difference of the feeders' resistance and / or a more symmetrical sectioning scheme of contact network.
We report on the search for the rare decay η→π0e+e− which is of interest to study C violation in the electromagnetic interaction which would indicate contributions from physics beyond the Standard ...Model, since the allowed decay via a two-photon intermediate state is strongly suppressed. The experiment has been performed using the WASA-at-COSY installation, located at the COSY accelerator of the Forschungszentrum Jülich, Germany. In total 3×107 events of the reaction pd→3Heη have been recorded at an excess energy of Q=59.8MeV. Based on this data set the C parity violating decay η→π0γ⁎→π0e+e− via a single-photon intermediate state has been searched for, resulting in new upper limits of Γ(η→π0e+e−)/Γ(η→π+π−π0)<3.28×10−5 and Γ(η→π0e+e−)/Γ(η→all)<7.5×10−6 (CL=90%), respectively.
This letter reports a first quantitative analysis of the contribution of higher partial waves in the charge symmetry breaking reaction dd→4Heπ0 using the WASA-at-COSY detector setup at an excess ...energy of Q=60MeV. The determined differential cross section can be parametrized as dσ/dΩ=a+bcos2θ⁎, where θ⁎ is the production angle of the pion in the center-of-mass coordinate system, and the results for the parameters are a=(1.55±0.46(stat)+0.32−0.8(syst))pb/sr and b=(13.1±2.1(stat)−2.7+1.0(syst))pb/sr. The data are compatible with vanishing p-waves and a sizable d-wave contribution. This finding should strongly constrain the contribution of the Δ isobar to the dd→4Heπ0 reaction and is, therefore, crucial for a quantitative understanding of quark mass effects in nuclear production reactions.
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