161 research outputs found
Some questions of space bioengineering
Zero-gravity offers selective effect on growth and metabolic activity unicellular organisms as well as unique opportunities in purification of organic compounds. These make it possible to consider the biosynthesis and recovery of certain metabolites economically feasible in space. Design, construction and operation of systems for the above mentioned purposes requires interdisciplinary actions within the scope of a new discipline: space bioengineering. The problems and perspectives of this discipline particularly in the application of bioreactor-recovery systems in space to manufacture metabolites of high economic and scientific value. Special attention is paid to pivotal factors such as various mass transport phenomena, contamination control, automatic control of optimum environment and synchronization of the operation of the biological (biosynthesis) and the physiochemical (recovery-purification) systems
The 3rd Flow Component as a QGP Signal
Earlier fluid dynamical calculations with QGP show a softening of the
directed flow while with hadronic matter this effect is absent. On the other
hand, we indicated that a third flow component shows up in the reaction plane
as an enhanced emission, which is orthogonal to the directed flow. This is not
shadowed by the deflected projectile and target, and shows up at measurable
rapidities, . To study the formation of this effect initial stages
of relativistic heavy ion collisions are studied. An effective string rope
model is presented for heavy ion collisions at RHIC energies. Our model takes
into account baryon recoil for both target and projectile, arising from the
acceleration of partons in an effective field. The typical field strength
(string tension) for RHIC energies is about 5-12 GeV/fm, what allows us to talk
about "string ropes". The results show that QGP forms a tilted disk, such that
the direction of the largest pressure gradient stays in the reaction plane, but
deviates from both the beam and the usual transverse flow directions. The
produced initial state can be used as an initial condition for further
hydrodynamical calculations. Such initial conditions lead to the creation of
third flow component. Recent measurements are promising that this effect
can be used as a diagnostic tool of the QGP
Modified Boltzmann Transport Equation and Freeze Out
We study Freeze Out process in high energy heavy ion reaction. The
description of the process is based on the Boltzmann Transport Equation (BTE).
We point out the basic limitations of the BTE approach and introduce Modified
BTE. The Freeze Out dynamics is presented in the 4-dimensional space-time in a
layer of finite thickness, and we employ Modified BTE for the realistic Freeze
Out description.Comment: 9 pages, 2 figure
Quark structure of hadrons and high energy collisions
There exists a large field for phenomenological models in which the knowledge
of the structure of hadrons in terms of QCD constituents obtained from deep
inelastic scatterings is related to their behaviour in soft processes. One of
the simplest and oldest models is the additive quark model, with the rules of
quark statistics following from it. Originally, the relations of quark
combinatorics for hadron yields were based on the qualitative description of a
multiparticle production process as a process of the production of
non-correlated quarks and antiquarks followed by their subsequent fusion into
hadrons [20],[21]. As a large amount of new precision measurements appear, and,
on the other hand, our understanding of QCD becomes deeper, a new level of
understanding of quark-gluon physics in the region of soft interactions forces
us to review the relations of quark combinatorics. To do so, an especially good
possibility is provided by the experimental data for hadronic Z^0 decays which
allow us to check the relations of quark combinatorics for a new type of
processes: quark jets in the decays Z^0 -> q\bar{q} -> hadrons [32].Comment: 55 pages, 23 figure
AtĂpusos aortacoarctatiĂłk sebĂ©szi kezelĂ©sĂ©nek hosszĂș tĂĄvĂș eredmĂ©nyei
Absztrakt
Bevezetés: Az aortacoarctatio a leggyakoribb congenitalis
cardiovascularis elvĂĄltozĂĄsok egyike, azok 5â8%-ĂĄban fordul elĆ. TĂpusos
elĆfordulĂĄsi helye az isthmicus szakasz. AtĂpusos helyen kialakulĂł coarctatio az
esetek mintegy 1%-ĂĄban fordul elĆ Ă©s többnyire sĂșlyos hypertoniĂĄval szövĆdik.
CĂ©lkitƱzĂ©s: A szerzĆk cĂ©lul tƱztĂ©k ki a kĂłrkĂ©p sebĂ©szi
kezelĂ©si lehetĆsĂ©geinek Ă©s azok hosszĂș tĂĄvĂș eredmĂ©nyeinek ismertetĂ©sĂ©t 27 beteg
mƱtéti kezelésével szerzett tapasztalataik alapjån. Módszer: A
35 Ă©vet felölelĆ utĂĄnkövetĂ©s sorĂĄn a diagnosztika Ă©s a kezelĂ©si mĂłdszerek
vĂĄltoztak. Napjainkban a morfolĂłgiai diagnĂłzis legĂĄltalĂĄnosabb mĂłdszerei a
komputertomogrĂĄfiĂĄs angiogrĂĄfia Ă©s a mĂĄgneses rezonanciĂĄs angiogrĂĄfia. Az
aortarekonstrukciĂł lehetĆsĂ©gei az endovascularis technikĂĄk bevezetĂ©sĂ©vel
gazdagodtak, de atĂpusos aortacoartatio esetĂ©ben a szerzĆk ma is tĂșlnyomĂłan
våltozatos sebészi megoldåsokat alkalmaznak. Eredmények: A
mƱtĂ©tek utĂĄn nem veszĂtettek el beteget. A hypertonia minden esetben jelentĆsen
csökkent. Gyermekkorban operålt esetekben a növekedés okozta testméretvåltozåsok
3 esetben Ășjabb rekonstrukciĂłs mƱtĂ©tet indokoltak.
KövetkeztetĂ©sek: Az atĂpusos aortacoarctatio individuĂĄlis
sebĂ©szi mĂłdszerekkel eredmĂ©nyesen kezelhetĆ. Gyermekkorban operĂĄlt esetekben a
testmĂ©ret-növekedĂ©s a rekonstruĂĄlt aortaszakasz revĂziĂłjĂĄt teheti szĂŒksĂ©gessĂ©.
Orv. Hetil., 2016, 157(26), 1043â1051
Photo-antagonism of the GABAA receptor
Neurotransmitter receptor trafficking is fundamentally important for synaptic transmission and neural network activity. GABAA receptors and inhibitory synapses are vital components of brain function, yet much of our knowledge regarding receptor mobility and function at inhibitory synapses is derived indirectly from using recombinant receptors, antibody-tagged native receptors and pharmacological treatments. Here we describe the use of a set of research tools that can irreversibly bind to and affect the function of recombinant and neuronal GABAA receptors following ultraviolet photoactivation. These compounds are based on the competitive antagonist gabazine and incorporate a variety of photoactive groups. By using site-directed mutagenesis and ligand-docking studies, they reveal new areas of the GABA binding site at the interface between receptor ÎČ and α subunits. These compounds enable the selected inactivation of native GABAA receptor populations providing new insight into the function of inhibitory synapses and extrasynaptic receptors in controlling neuronal excitation
Future air quality in Europe: a multi-model assessment of projected exposure to ozone
In order to explore future air quality in Europe at the 2030 horizon, two emission scenarios developed in the framework of the Global Energy Assessment including varying assumptions on climate and energy access policies are investigated with an ensemble of six regional and global atmospheric chemistry transport models. <br><br> A specific focus is given in the paper to the assessment of uncertainties and robustness of the projected changes in air quality. The present work relies on an ensemble of chemistry transport models giving insight into the model spread. Both regional and global scale models were involved, so that the ensemble benefits from medium-resolution approaches as well as global models that capture long-range transport. For each scenario a whole decade is modelled in order to gain statistical confidence in the results. A statistical downscaling approach is used to correct the distribution of the modelled projection. Last, the modelling experiment is related to a hind-cast study published earlier, where the performances of all participating models were extensively documented. <br><br> The analysis is presented in an exposure-based framework in order to discuss policy relevant changes. According to the emission projections, ozone precursors such as NO<sub>x</sub> will drop down to 30% to 50% of their current levels, depending on the scenario. As a result, annual mean O<sub>3</sub> will slightly increase in NO<sub>x</sub> saturated areas but the overall O<sub>3</sub> burden will decrease substantially. Exposure to detrimental O<sub>3</sub> levels for health (SOMO35) will be reduced down to 45% to 70% of their current levels. And the fraction of stations where present-day exceedences of daily maximum O<sub>3</sub> is higher than 120 ÎŒg m<sup>â3</sup> more than 25 days per year will drop from 43% down to 2 to 8%. <br><br> We conclude that air pollution mitigation measures (present in both scenarios) are the main factors leading to the improvement, but an additional cobenefit of at least 40% (depending on the indicator) is brought about by the climate policy
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