259 research outputs found
Methods of predicting relapsing hemorrhage.
In this article the authors presented their own original methods for predicting ulcerous gastroduodenal bleeding defended by Patent of Ukraine. The implementation of these procedures led to substantial lowing of recurrent hamorrhage rate – more than twice. All methods have pathogenetic foundation and are based on ulcerogenesis mechanisms revealed during the longlasting complex clinical and experimental research. In such a way surgeons obtain some possibilities of early diagnostics of bleeding relapses and adequate treatment and effective hemorrhage prevention accordingly.
Design, characterisation and validation of a haptic interface based on twisted string actuation.
This paper presents the design and experimental characterisation of a wrist haptic interface based on a twisted string actuator. The interface is designed for controlled actuation of wrist flexion/extension and is capable of rendering torque feedback through a rotary handle driven by the twisted string actuator and spring-loaded cable mechanisms. The interface was characterised to obtain its static and dynamic haptic feedback rendering capabilities. Compliance in the spring and actuation mechanism makes the interface suitable for smooth rendering of haptic feedback of large magnitudes due to the high motion transmission ratio of the twisted strings. Haptic virtual wall rendering capabilities are demonstrated
Laser acceleration of ion beams
We consider methods of charged particle acceleration by means of
high-intensity lasers. As an application we discuss a laser booster for heavy
ion beams provided, e.g. by the Dubna nuclotron. Simple estimates show that a
cascade of crossed laser beams would be necessary to provide additional
acceleration to gold ions of the order of GeV/nucleon.Comment: 4 pages, 4 figures, Talk at the Helmholtz International Summer School
"Dense Matter in heavy Ion Collisions and Astrophysics", August 21 -
September 1, 2006, JINR Dubna, Russia; v2, misprints correcte
Methods of predicting relapsing hemorrhage.
In this article the authors presented their own original methods for predicting ulcerous gastroduodenal bleeding defended by Patent of Ukraine. The implementation of these procedures led to substantial lowing of recurrent hamorrhage rate – more than twice. All methods have pathogenetic foundation and are based on ulcerogenesis mechanisms revealed during the longlasting complex clinical and experimental research. In such a way surgeons obtain some possibilities of early diagnostics of bleeding relapses and adequate treatment and effective hemorrhage prevention accordingly
Right Handed Weak Currents in Sum Rules for Axialvector Constant Renormalization
The recent experimental results on deep inelastic polarized lepton scattering
off proton, deuteron and He together with polari% zed neutron
-decay data are analyzed. It is shown that the problem of Ellis-Jaffe
and Bjorken sum rules deficiency and the neutron paradox could be solved
simultaneously by assuming the small right handed current (RHC) admixture in
the weak interaction Lagrangian. The possible RHC impact on pion-nucleon
-term and Gamow-Teller sum rule for nuclear reactions is
pointed out.Comment: to be published in Phys. Rev. Lett. LaTeX, 8 pages, 21 k
Analysis of solar neutrino induced double beta processes for several nuclei
We investigate neutrino flux induced double beta transitions in targets built
of Cd112, Cd114, Cd116 and O18 isotopes. In addition to known beta^- beta^-
channel we consider new beta^- beta^+ and beta^- beta^+ gamma modes of the
neutrino induced double beta process. A possibility of detection of the solar
neutrinos via the induced double beta transitions of interest is discussed. We
note that the beta^- part of the solar neutrino induced beta^- beta^+ process
in O18 was already discussed in Ref. [9,10] in connection with a possible
influence of high energy electron production of this origin on the
SuperKamiokande results.Comment: 5 pages, LaTeX. Talk presented by S. V. Semenov on International
Workhop on Non-Accelerator New Physics (NANP'01), Dubna, Russia, June 2001,
to be published in Phys. Atom. Nucl. (2002
"The obesity paradox" in patients with atrial fibrillation according to the results of the REKUR-AF study
To evaluate the effect of excess body weight (EBW) and obesity on the survival of patients with atrial fibrillation (AF) in the REKUR-AF stud
The spark-associated soliton model for pulsar radio emission
We propose a new, self-consistent theory of coherent pulsar radio emission
based on the non-stationary sparking model of Ruderman & Sutherland (1975),
modified by Gil & Sendyk (2000) in the accompanying Paper I. According to these
authors, the polar cap is populated as densely as possible by a number of
sparks with a characteristic perpendicular dimension D approximately equal to
the polar gap height scale h, separated from each other also by about h. Each
spark reappears in approximately the same place on the polar cap for a time
scale much longer than its life-time and delivers to the open magnetosphere a
sequence of electron-positron clouds which flow orderly along a flux tube of
dipolar magnetic field lines. The overlapping of particles with different
momenta from consecutive clouds leads to effective two-stream instability,
which triggers electrostatic Langmuir waves at the altitudes of about 50
stellar radii. The electrostatic oscillations are modulationally unstable and
their nonlinear evolution results in formation of ``bunch-like'' charged
solitons. A characteristic soliton length along magnetic field lines is about
30 cm, so they are capable of emitting coherent curvature radiation at radio
wavelengths. The net soliton charge is about 10^21 fundamental charges,
contained within a volume of about 10^14 cm^3. For a typical pulsar, there are
about 10^5 solitons associated with each of about 25 sparks operating on the
polar cap at any instant. One soliton moving relativisticaly along dipolar
field lines with a Lorentz factor of the order of 100 generates a power of
about 10^21 erg/s by means of curvature radiation. Then the total power of a
typical radio pulsar can be estimated as being about 10^(27-28) erg/s.Comment: 27 pages, 5 figures, accepted by Ap
Cultivars and lines from ICARDA in spring durum wheat (<i>Triticum durum</i> Desf.) breeding in the Lower Volga region
Background. In 1991, under the cooperation agreement, the Federal Center of Agriculture Research (FCAR) of the South-East Region received the first improved accessions from the International Center for Agricultural Research in the Dry Areas (ICARDA). The objective of this work was to study the source material developed under comparable conditions of dryland agriculture and include the best accessions in scientific breeding programs.Material and methods. The presented data resulted from the study of spring durum wheat cultivars and lines from ICARDA (Aleppo, Syria), conducted in 1991–1998. Accessions with the best indicators of grain quality, adapted to the conditions of the Lower Volga, were selected and included into the crossing program. Grain analysis was carried out using the conventional methods for durum wheat as well as those modified by the Spring Durum Wheat Breeding Laboratory of the FCAR of the South-East.Result and conclusion. Many years of work led to identifying 22 lines of spring durum wheat, selected in the breeding nursery of the Main Competitive Trails (MCT) and in different years involved in complex multistep hybridization. The spring durum wheat cultivar ‘Lilek’ was included into the State Register for Selection Achievements in 2009, while cv. ‘Tamara’ was submitted to the State Variety Trials in 2020
Particle Motion in Rapidly Oscillating Potentials: The Role of the Potential's Initial Phase
Rapidly oscillating potentials with a vanishing time average have been used
for a long time to trap charged particles in source-free regions. It has been
argued that the motion of a particle in such a potential can be approximately
described by a time independent effective potential, which does not depend upon
the initial phase of the oscillating potential. However, here we show that the
motion of a particle and its trapping condition significantly depend upon this
initial phase for arbitrarily high frequencies of the potential's oscillation.
We explain this novel phenomenon by showing that the motion of a particle is
determined by the effective potential stated in the literature only if its
initial conditions are transformed according to a transformation which we show
to significantly depend on the potential's initial phase for arbitrarily high
frequencies. We confirm our theoretical findings by numerical simulations.
Further, we demonstrate that the found phenomenon offers new ways to manipulate
the dynamics of particles which are trapped by rapidly oscillating potentials.
Finally, we propose a simple experiment to verify the theoretical findings of
this work.Comment: 9 pages, 8 figures, published in PR
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