Investigation of Corrosion Behavior of Bioactive Coverings on Commercially Pure Titanium and its Alloys

A microporous and macroporous bioactive coatings on boimedical titanium alloys (VT1-0, VT6, Ti-6Al-7Nb) were formed by a micro-arc oxidation method. The effect of the phase composition of microporous and macroporous coatings on corrosion behavior titanium and its alloys was investigated. The results show that phase composition of the coatings microporous presented only titanium oxides: anatase and rutile, at that the phase composition macroporous coatings consists of anatase, rutile and calcium phosphate compounds: tricalcium phosphate (TCP) α-Ca3(PO4)2 and calcium deficient hydroxyapatite Ca9HPO4(PO4)5OH. Corrosion behavior of MAO coatings was investigated in solution 0.9 % NaCl using potentiodynamic polarization tests. The microporous coatings exhibited a more highest corrosion resistance than macroporous coatings, it is connected with containing calcium phosphate compounds in macroporous coatings

Investigation of Corrosion Behavior of Bioactive Coverings on Commercially Pure Titanium and its Alloys

A microporous and macroporous bioactive coatings on boimedical titanium alloys (VT1-0, VT6, Ti-6Al-7Nb) were formed by a micro-arc oxidation method. The effect of the phase composition of microporous and macroporous coatings on corrosion behavior titanium and its alloys was investigated. The results show that phase composition of the coatings microporous presented only titanium oxides: anatase and rutile, at that the phase composition macroporous coatings consists of anatase, rutile and calcium phosphate compounds: tricalcium phosphate (TCP) α-Ca3(PO4)2 and calcium deficient hydroxyapatite Ca9HPO4(PO4)5OH. Corrosion behavior of MAO coatings was investigated in solution 0.9 % NaCl using potentiodynamic polarization tests. The microporous coatings exhibited a more highest corrosion resistance than macroporous coatings, it is connected with containing calcium phosphate compounds in macroporous coatings

Quantum Correlations in Two-Boson Wavefunctions

We present the Schmidt decomposition for arbitrary wavefunctions of two indistinguishable bosons, extending the recent studies of entanglement or quantum correlations for two fermion systems [J. Schliemann et al., Phys. Rev. B {\bf 63}, 085311 (2001) and quant-ph/0012094]. We point out that the von Neumann entropy of the reduced single particle density matrix remains to be a good entanglement measure for two identical particles.Comment: in press at Phys. Rev.

Методы анализа микроальтернации ЭКГ-сигнала

The paper presents the methods of analysis of the ECG-signal alternations, which are increasingly being used in everyday clinical practice. Evaluation of these indicators is an important component of the analysis of myocardial electrical instability and the development of potentially dangerous arrhythmias. New technologies of reception and analysis of the electric field of the heart reflect the creation of a new generation of functional diagnostic methods. Now the method of dispersion mapping is increasingly being used for the screening in Russia.В работе представлены используемые методы анализа альтернаций ЭКГ-сигнала, которые все шире используются в повседневной клинической практике. Оценка данных показателей является важной составляющей анализа электрической нестабильности миокарда и развития потенциально-опасных аритмий. Новые технологии получения и анализа электрического поля сердца отражают создание нового поколения методов функциональной диагностики. Метод дисперсионного картирования находит все большее применение в РФ в настоящее время для проведения скрининга

Rift- and arc-type basaltic volcanism of the Sredinny Ridge, Kamchatka: case study of the Payalpan volcano-tectonic structure

Trace element data for volcanic rocks of the Payalpan volcano-tectonic structure (Sredinny ridge, Kamchatka) allows distinguishing typical island-arc, rift and transitional series of rocks. Island-arc basaltic and differentiated magmas erupted in the Late Miocene and Pliocene. In the Late Pliocene – Early Pleistocene, there was a voluminous event dominated by the basaltic magmas of rift-type series. This event followed by voluminous eruptions of mainly basaltic andesites of transitional series. At the end of the Pleistocene and probably during the Holocene volume of eruptions diminished and composition of magmas shifted towards rift-type basaltic series. Practically in the same area in the Pleistocene and Holocene the Icha volcano produced basaltic andesite to rhyolite magmas of the island-arc and transitional series. Reasons for spatial overlapping and temporal evolution of the island-arc and rift magma types are also discussed

Использование устройств аспирации тромба при острых окклюзиях коронарных артерий

There were analyzed 38 patients with acute coronary syndrome with ST segment elevation. Every patient was revealed by coronary angiography to have an occlusion in one of the main coronary arteries. The patients were divided in two groups by the technique of percutaneous coronary intervention. In the first group (n = 18) after mechanical recanalisation with wire we used a catheter for thrombus aspiration. Furthermore according to results after coronary angiography these patients underwent either direct stenting or predilatation with further stenting. After mechanical recanalisation in the second group (n = 20) routine stenting with predilatation were performed. The reperfusion quality was evaluated by TIMI scale by the angiography and ST segment decrease during 30 minutes after the intervention. It was statistically proved that adequate reperfusion was achieved in the group with thrombus aspiration catheter.Проанализированы результаты обследования и лечения 38 пациентов с инфарктом миокарда с подъемом сегмента ST. По результатам коронарной ангиографии во всех наблюдениях определялась окклюзия одной из магистральных коронарных артерий. Пациенты были разделены на две группы в зависимости от тактики выполнения чрескожного коронарного вмешательства. В первой группе (n = 18) после механической реканализации проводником в зону окклюзии вводили катетер для аспирации тромба. Далее в зависимости от ангиографического результата выполнялось прямое стентирование поражения или предварительная баллонная ангиопластика с последующим стентированием. Во второй группе (n = 20) после механической реканализации выполнялась баллонная ангиопластика с последующим стентированием. Адекватность реперфузии оценивалась по степени восстановления кровотока по шкале TIMI по результатам коронарной ангиографии и по снижению сегмента ST по данным ЭКГ через 30 минут после окончания вмешательства. При сравнении результатов первой и второй групп установлено, что достоверно чаще в первой группе пациентов удавалось достигнуть адекватной реперфузии

Radiative Corrections to One-Photon Decays of Hydrogenic Ions

Radiative corrections to the decay rate of n=2 states of hydrogenic ions are calculated. The transitions considered are the M1 decay of the 2s state to the ground state and the E1(M2) decays of the $2p_{1/2}$ and $2p_{3/2}$ states to the ground state. The radiative corrections start in order $\alpha (Z \alpha)^2$, but the method used sums all orders of $Z\alpha$. The leading $\alpha (Z\alpha)^2$ correction for the E1 decays is calculated and compared with the exact result. The extension of the calculational method to parity nonconserving transitions in neutral atoms is discussed.Comment: 22 pages, 2 figure

Enhancement of bichromatic high-harmonic generation with a high-frequency field

Using a high-frequency field superposed to a linearly polarized bichromatic laser field composed by a wave with frequency $\omega$ and a wave with frequency $2\omega$, we show it is possible to enhance the intensity of a group of high harmonics in orders of magnitude. These harmonics have frequencies about 30% higher than the monochromatic-cutoff frequency, and, within the three-step-model framework, correspond to a set of electron trajectories for which tunneling ionization is strongly suppressed. Particular features in the observed enhancement suggest that the high-frequency field provides an additional mechanism for the electron to reach the continuum. This interpretation is supported by a time-frequency analysis of the harmonic yield. The additional high frequency field permits the control of this group of harmonics leaving all other sets of harmonics practically unchanged, which is an advantage over schemes involving only bichromatic fields.Comment: 6 pages RevTex, 5 figures (ps files), Changes in text, figures, references and equations include

Cardiosynchronous electromyostimulation in patients with acute heart failure

Material and methods: The study included 62 AHF patients: Group I - those receiving only standard pharmacological therapy; and Group II - those in whom standard pharmacological therapy was ineffective after 12 hours, and who were also administered ECSEMS sessions for the next 7 days. The examination included multi-frequency bio-impedance measurement and dispersion mapping.Aim: To study the effectiveness of the external cardiosynchronous electromyostimulation (ECSEMS) in patients with different variants of acute heart failure (AHF).Results: Clinical symptoms were less severe in Group I. In 64% of the Group II patients, the combination treatment was associated with a positive dynamics of the water balance parameters. The 7-day ECSEMS, as a part of the complex management of AHF patients, significantly reduced the one-month lethality, although did not change the one-year survival.Conclusion: The ECSEMS method could be used in order to increase the effectiveness of the conservative treatment of AHF patients