109 research outputs found

    The analysis of pi^{-} mesons produced in nucleus-nucleus collisions at a momentum of 4.5 GeV/c/nucleon in light front variables

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    The light front analysis of pi^{-} mesons in He(Li,C), C-Ne, C-Cu and O-Pb collisions is carried out. The phase space of secondary pions is divided into two parts in one of which the thermal equilibrium assumption seems to be in a good agreement with the data. Corresponding temperatures T are extracted and their dependence on (A_{P}*A_{T})^{1/2} is studied. The results are compared with the predictions of the Quark-Gluon String Model (QGSM). The QGSM satisfactorily reproduces the experimental data for light and intermediate-mass nuclei.Comment: 14 pages with 9 postscript figure

    Light-Front Analysis of pi^{-} Mesons Produced in Mg - Mg Collisions at 4.3 a Gev/c

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    Light-front analysis of pi^{-} mesons in Mg-Mg collisions is carried out. The phase space of secondary pions is naturally divided into two parts in one of which the thermal equilibration assumption seems to be in a good agreement with data. Corresponding temperatures are extracted and compared to the results of other experiments. The experimental results have been compared with the predictions of the Quark Gluon String Model (QGSM) and satisfactory agreement between the experimental data and the model has been found.Comment: 14 pages with 7 postscript figures. accepted for publication in Nucl. Phys.

    The Light Front Analysis of pi^{-} Mesons Produced in the Relativistic Nucleus-Nucleus Collisions

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    The light front analysis of pi^{-} mesons in A_{P} (He, C, Mg, O) + A_{T} (Li,C, Ne, Mg,Cu,Pb) collisions is carried out. The phase space of secondary pions is naturally divided into two parts in one of which the thermal equilibration assumption seems to be in a good agreement with data. Corresponding temperatures are extracted and compared to the results of other experiments. The dependence of the average temperature T on (A_{P}*A_{T})^{1/2} is studied.Comment: 15 pages with 13 postscript figure

    Eta-mesic nuclei in relativistic mean-field theory

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    With the eta-nucleon (eta N) interaction Lagrangian deduced from chiral perturbation theory, we study the possible eta-mesic nuclei in the framework of relativistic mean-field theory. The eta single-particle energies are sensitive to the eta N scattering length, and increase monotonically with the nucleon number A. If the scattering length is in the range of a^{eta N}=0.75-1.05 fm and the imaginary potential V_{0}-15 MeV, some discrete states of C, O and Ne eta bound states should be identified in experiments. However, when the scattering length a^{eta N} 30 MeV, no discrete eta meson bound states could be observed in experiments.Comment: 6 page

    Differential Transverse Flow in Central C-Ne and C-Cu Collisions at 3.7 GeV/nucleon

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    Differential transverse flow of protons and pions in central C-Ne and C-Cu collisions at a beam energy of 3.7 GeV/nucleon was measured as a function of transverse momentum at the SKM-200-GIBS setup of JINR. In agreement with predictions of a transversely moving thermal model, the strength of proton differential transverse flow is found to first increase gradually and then saturate with the increasing transverse momentum in both systems. While pions are preferentially emitted in the same direction of the proton transverse flow in the reaction of C-Ne, they exhibit an anti-flow to the opposote direction of the proton transverse flow in the reaction of C-Cu due to stronger shadowing effects of the heavier target in thr whole range of transverse momentum.Comment: 15 pages, 5 figure

    Homobivalent Lamellarin-Like Schiff Bases: In Vitro Evaluation of Their Cancer Cell Cytotoxicity and Multitargeting Anti-Alzheimer's Disease Potential

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    Marine alkaloids belonging to the lamellarins family, which incorporate a 5,6-dihydro-1-phenylpyrrolo[2,1-a]isoquinoline (DHPPIQ) moiety, possess various biological activities, spanning from antiviral and antibiotic activities to cytotoxicity against tumor cells and the reversal of multidrug resistance. Expanding a series of previously reported imino adducts of DHPPIQ 2-carbaldehyde, novel aliphatic and aromatic Schiff bases were synthesized and evaluated herein for their cytotoxicity in five diverse tumor cell lines. Most of the newly synthesized compounds were found noncytotoxic in the low micromolar range (<30 μM). Based on a Multi-fingerprint Similarity Search aLgorithm (MuSSeL), mainly conceived for making protein drug target prediction, some DHPPIQ derivatives, especially bis-DHPPIQ Schiff bases linked by a phenylene bridge, were prioritized as potential hits addressing Alzheimer's disease-related target proteins, such as cholinesterases (ChEs) and monoamine oxidases (MAOs). In agreement with MuSSeL predictions, homobivalent para-phenylene DHPPIQ Schiff base 14 exhibited a noncompetitive/mixed inhibition of human acetylcholinesterase (AChE) with Ki in the low micromolar range (4.69 μM). Interestingly, besides a certain inhibition of MAO A (50% inhibition of the cell population growth (IC50) = 12 μM), the bis-DHPPIQ 14 showed a good inhibitory activity on self-induced β-amyloid (Aβ)1-40 aggregation (IC50 = 13 μM), which resulted 3.5-fold stronger than the respective mono-DHPPIQ Schiff base 9

    Polarization of Lambda^0 hyperons in nucleus-nucleus collisions at high energies

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    The measurement of Lambda^0 hyperons polarization in nucleus-nucleus collisions is considered as one of possible tools to study the phase transition. Fixed target and collider experiments are discussed for the case of Lambda^0's production from Au-Au central collisions at \sqrt{s_{NN}} of several GeV.Comment: 15 pages, 6 figure

    ВЛИЯНИЕ СОСТАВА ТОРФОБРИКЕТОВ НА ФОРМИРОВАНИЕ РАССАДЫ ОГУРЦА В ИНТЕНСИВНОЙ СВЕТОКУЛЬТУРЕ

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    Obtaining high-quality seedlings is an essential condition for growing vegetables in modern cultivation facilities of protected ground. The influence of the composition and properties of peat briquettes on the growth and development of hybrid F1 of cucumber Zozulya seedlings, indicators of plant leaves photosynthetic activity, their net productivity in cultivation under controlled conditions of intensive light culture were investigated. It is shown how the change in the composition of peat briquettes affects their hydrophysical properties: volume, density, moisture absorbing capacity, etc., which is reflected in the state of cucumber seedlings. Thus, for the grown cucumber seedlings, peat briquettes had more favorable hydrophysical properties, which included, in addition to neutralized peat, Cambrian clay, separately or in combination with straw in the amount of 10% of the peat volume, or with sapropel. The moisture absorbing capacity in the considered peat briquettes was optimal for growing plants in conditions of intensive light culture and ranged from 617 to 774%. Optimization of the hydrophysical properties of peat briquettes was positively reflected in the photosynthetic activity of the leaves. The photosynthetic potential increased by 20-29%, the leaf surface area – by 19-40%; net productivity of plants photosynthesis – by 0.6-3.2 g/m2 per day, which eventually led to the formation of plants with a higher biomass – by 10-48%. An increase in the content of straw in the peat briquette to 20% led to a decrease in the moisture absorbing capacity of the peat briquette, which contributed to a certain deterioration in the physiological state of plants and, as a consequence, to a tendency towards to reduce the mass of plant seedlings.Получение качественной рассады является неотъемлемым условием при выращивании овощных культур в современных культивационных сооружениях защищенного грунта. Исследовано влияние состава и свойств торфобрикетов на рост и развитие рассады гибрида F1 огурца Зозуля, показатели фотосинтетической активности листьев растений, их нетто-продуктивность при культивировании в регулируемых условиях интенсивной светокультуры. Показано, как изменение состава торфобрикетов влияет на их гидрофизические свойства: объем, плотность, водопоглощающую способность и др., что отражается на состоянии рассады огурца. Так, для выращиваемой рассады огурца более благоприятными гидрофизическими свойствами обладали торфобрикеты, в состав которых кроме нейтрализованного торфа входили кембрийская глина, отдельно или в сочетании с соломой в количестве 10% от объема торфа, или с сапропелем. Влагопоглощающая способность в рассматриваемых торфобрикетах была оптимальной для выращивания растений в условиях интенсивной светокультуры и находилась в диапазоне от 617 до 774%. Оптимизация гидрофизических свойств торфобрикетов, положительным образом отражалась на показателях фотосинтетической деятельности листьев. Фотосинтетический потенциал увеличивался на 20-29%, площадь листовой поверхности листьев возрастала на 19-40%; чистая продуктивность фотосинтеза растений – на 0,6-3,2 г/м2 сутки, что в конечном итоге приводило к формированию растений с более высокой биомассой – на 10- 48%. Увеличение содержания соломы в торфобрикете до 20% приводило к снижению влагопоглощающей способности торфобрикета, что способствовало некоторому ухудшению физиологического состояния растений и, как следствие, проявлению тенденции к снижению массы рассады растений
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