148 research outputs found
Аналіз епізоотичного стану з класичної чуми свиней у світі за період 2000–2009 та 2012–2020 роки
Using information from the International Epizootic Bureau (IEB), an analysis of the epizootic status of classical swine fever (Swine Fever) in the countries of the world for nine years (2012–2020) was carried out, taking into account the continental affiliation. The epizootic state, concerning SF, depends on the economic situation in the states, the control of vaccinations in homesteads, the presence of grazing pigs, and their contact with wild boars. During the specified period, 1 case of SF from wild animals was registered on the territory of Ukraine in the Kyiv region. The number of disease outbreaks was calculated, and the data obtained were compared with the previously analyzed period of 2000–2009. According to the results of the analysis, it was established that the number of cases of SF for the period 2012–2020 indicates a higher degree of intensity of the epizootic state in Asia, South America, and Europe in comparison with the previous period – 2000–2009, and during the period 2012–2020, the Emergencies were registered on the territory of Europe (179 cases), South America (2586 cases), Asia (1452 cases). In our opinion, in the countries of Asia and South America, the intensity of the epizootic state with SF depends on the low level of biosecurity in homesteads (feeding uninfected food waste to pigs, free grazing and contact with wild boars in the absence of their vaccination against SF), unlike in Europe, where the intensity of the epizootic the situation is primarily related to the cases of this disease among the population of wild pigs, since there is a reliable level of biosecurity in pig farms and the lack of livestock vaccination. In the countries of Asia, the stress of the epizootic state regarding SF is also explained by the fact that a highly virulent strain of the SF virus was introduced into the territory of these countries. Thanks to the implementation by the State Veterinary Services of Asian countries of appropriate programs to fight against SF, where the main thing was the destruction and disposal of sick and dead pigs in negative points in dangerous zones, it was possible to stop the spread and manifestation of this disease. We believe that the permanent epizootic well-being with SF on the territory of Ukraine gives grounds for the development and implementation of a system of measures to eradicate the pathogen on its territory, which can be effectively achieved only by stopping the preventive vaccination of the pig herd.Використовуючи інформацію Міжнародного епізоотичного бюро (МЕБ) проведено аналіз епізоотичного стану щодо класичної чуми свиней (КЧС) у країнах світу за 9 річний період (2012–2020 рр.) з урахуванням континентальної належності. Епізоотичний стан, щодо КЧС залежить від економічної ситуації в державах, контролю щеплень присадибних господарствах наявність випасу поголів’я свиней та їх контакту з дикими кабанами. За зазначений період на території України реєструвався 1 випадок КЧС від диких тварин в Київській області. Здійснено підрахунок кількості спалахів хвороби та проведено порівняння отриманих даних з раніше аналізованим періодом 2000–2009 рр. За результатами проведеного аналізу встановлено, що кількість випадків КЧС за період 2012–2020 свідчить про більш високий ступінь напруженості епізоотичного стану в Азії, Південній Америці та Європі порівняно з попереднім періодом – 2000–2009 роки, так за період 2012–2020 рр. КЧС реєструвалась на території Європи (179 випадків), Південної Америки (2586 випадків), Азії (1452випадків). На нашу думку у країнах Азії та Південної Америки напруженість епізоотичного стану з КЧС залежить від низького рівня біобезпеки присадибних господарствах (згодовування незнезаражених харчових відходів свиням, вільний випас та контакт з дикими кабанами відсутності їх вакцинації проти КЧС), на відміну від Європи, де напруженість епізоотичної ситуації у першу чергу пов’язана саме з випадками цього захворювання серед популяції диких свиней, оскільки у свиногосподарствах існує надійний рівень біобезпеки, та відсутність щеплення поголів’я. У країнах Азії напруження епізоотичного стану щодо КЧС пояснюється ще й тим, що на територію цих країн був занесений високовірулентний штам вірусу КЧС. Завдяки впровадженню Державними ветеринарними службами країн Азії відповідних програм боротьби з КЧС, де основним було знищення та утилізація хворих і загиблих свиней в неблагополучних пунктах за загрозливих зонах вдалося припинити поширення та прояв цієї хвороби. Ми вважаємо, що стале епізоотичне благополуччя з КЧС на території України дає підстави до розробки та впровадження системи заходів з ерадикації збудника на її території, яку можна ефективно досягнути лише шляхом припинення профілактичного щеплення свинопоголів’я
Multiparticle angular correlations: a probe for the sQGP at RHIC
A novel decomposition technique is used to extract the centrality dependence
of di-jet properties and yields from azimuthal correlation functions obtained
in Au+Au collisions at =200 GeV. The width of the
near-side jet shows very little dependence on centrality. In contrast, the
away-side jet indicates substantial broadening as well as hints for for a local
minimum at for central and mid-central events. The yield of
jet-pairs (per trigger particle) slowly increases with centrality for both the
near- and away-side jets. These observed features are compatible with several
recent theoretical predictions of possible modifications of di-jet
fragmentation by a strongly interacting medium. Several new experimental
approaches, including the study of flavor permutation and higher order
multi-particle correlations, that might help to distinguish between different
theoretical scenarios are discussed.Comment: Proceedings of the MIT workshop on correlations and fluctation
The Cold Peace: Russo-Western Relations as a Mimetic Cold War
In 1989–1991 the geo-ideological contestation between two blocs was swept away, together with the ideology of civil war and its concomitant Cold War played out on the larger stage. Paradoxically, while the domestic sources of Cold War confrontation have been transcended, its external manifestations remain in the form of a ‘legacy’ geopolitical contest between the dominant hegemonic power (the United States) and a number of potential rising great powers, of which Russia is one. The post-revolutionary era is thus one of a ‘cold peace’. A cold peace is a mimetic cold war. In other words, while a cold war accepts the logic of conflict in the international system and between certain protagonists in particular, a cold peace reproduces the behavioural patterns of a cold war but suppresses acceptance of the logic of behaviour. A cold peace is accompanied by a singular stress on notions of victimhood for some and undigested and bitter victory for others. The perceived victim status of one set of actors provides the seedbed for renewed conflict, while the ‘victory’ of the others cannot be consolidated in some sort of relatively unchallenged post-conflict order. The ‘universalism’ of the victors is now challenged by Russia's neo-revisionist policy, including not so much the defence of Westphalian notions of sovereignty but the espousal of an international system with room for multiple systems (the Schmittean pluriverse)
Transverse energy production and charged-particle multiplicity at midrapidity in various systems from to 200 GeV
Measurements of midrapidity charged particle multiplicity distributions,
, and midrapidity transverse-energy distributions,
, are presented for a variety of collision systems and energies.
Included are distributions for AuAu collisions at ,
130, 62.4, 39, 27, 19.6, 14.5, and 7.7 GeV, CuCu collisions at
and 62.4 GeV, CuAu collisions at
GeV, UU collisions at GeV,
Au collisions at GeV, HeAu collisions at
GeV, and collisions at
GeV. Centrality-dependent distributions at midrapidity are presented in terms
of the number of nucleon participants, , and the number of
constituent quark participants, . For all collisions
down to GeV, it is observed that the midrapidity data
are better described by scaling with than scaling with . Also presented are estimates of the Bjorken energy density,
, and the ratio of to ,
the latter of which is seen to be constant as a function of centrality for all
systems.Comment: 706 authors, 32 pages, 20 figures, 34 tables, 2004, 2005, 2008, 2010,
2011, and 2012 data. v2 is version accepted for publication in Phys. Rev.
Medium modification of jet fragmentation in Au+Au collisions at sqrt(s_NN)=200 GeV measured in direct photon-hadron correlations
The jet fragmentation function is measured with direct photon-hadron
correlations in p+p and Au+Au collisions at sqrt(s_NN)=200 GeV. The p_T of the
photon is an excellent approximation to the initial p_T of the jet and the
ratio z_T=p_T^h/p_T^\gamma is used as a proxy for the jet fragmentation
function. A statistical subtraction is used to extract the direct photon-hadron
yields in Au+Au collisions while a photon isolation cut is applied in p+p. I_
AA, the ratio of jet fragment yield in Au+Au to that in p+p, indicates
modification of the jet fragmentation function. Suppression, most likely due to
energy loss in the medium, is seen at high z_T. The fragment yield at low z_T
is enhanced at large angles. Such a trend is expected from redistribution of
the lost energy into increased production of low-momentum particles.Comment: 562 authors, 70 insitutions, 8 pages, and 3 figures. Submitted to
Phys. Rev. Lett. v2 has minor changes to improve clarity. Plain text data
tables for the points plotted in figures for this and previous PHENIX
publications are (or will be) publicly available at
http://www.phenix.bnl.gov/papers.htm
Transverse momentum and centrality dependence of dihadron correlations in Au+Au collisions at sqrt(s_NN)=200 GeV: Jet-quenching and the response of partonic matter
Azimuthal angle \Delta\phi correlations are presented for charged hadrons
from dijets for 0.4 < p_T < 10 GeV/c in Au+Au collisions at sqrt(s_NN) = 200
GeV. With increasing p_T, the away-side distribution evolves from a broad to a
concave shape, then to a convex shape. Comparisons to p+p data suggest that the
away-side can be divided into a partially suppressed "head" region centered at
Delta\phi ~ \pi, and an enhanced "shoulder" region centered at Delta\phi ~ \pi
+/- 1.1. The p_T spectrum for the "head" region softens toward central
collisions, consistent with the onset of jet quenching. The spectral slope for
the "shoulder" region is independent of centrality and trigger p_T, which
offers constraints on energy transport mechanisms and suggests that the
"shoulder" region contains the medium response to energetic jets.Comment: 420 authors from 58 institutions, 6 pages, 4 figures. Submitted to
Physical Review Letters. Plain text data tables for the points plotted in
figures for this and previous PHENIX publications are (or will be) publicly
available at http://www.phenix.bnl.gov/papers.htm
Measurements of elliptic and triangular flow in high-multiplicity HeAu collisions at GeV
We present the first measurement of elliptic () and triangular ()
flow in high-multiplicity HeAu collisions at
GeV. Two-particle correlations, where the particles have a large separation in
pseudorapidity, are compared in HeAu and in collisions and
indicate that collective effects dominate the second and third Fourier
components for the correlations observed in the HeAu system. The
collective behavior is quantified in terms of elliptic and triangular
anisotropy coefficients measured with respect to their corresponding
event planes. The values are comparable to those previously measured in
Au collisions at the same nucleon-nucleon center-of-mass energy.
Comparison with various theoretical predictions are made, including to models
where the hot spots created by the impact of the three He nucleons on the
Au nucleus expand hydrodynamically to generate the triangular flow. The
agreement of these models with data may indicate the formation of low-viscosity
quark-gluon plasma even in these small collision systems.Comment: 630 authors, 9 pages, 4 figures, 2 tables. v2 is the version accepted
for publication by Physical Review Letters. Plain text data tables for the
points plotted in figures for this and previous PHENIX publications are (or
will be) publicly available at http://www.phenix.bnl.gov/papers.htm
Quantitative Constraints on the Transport Properties of Hot Partonic Matter from Semi-Inclusive Single High Transverse Momentum Pion Suppression in Au+Au collisions at sqrt(s_NN) = 200 GeV
The PHENIX experiment has measured the suppression of semi-inclusive single
high transverse momentum pi^0's in Au+Au collisions at sqrt(s_NN) = 200 GeV.
The present understanding of this suppression is in terms of energy-loss of the
parent (fragmenting) parton in a dense color-charge medium. We have performed a
quantitative comparison between various parton energy-loss models and our
experimental data. The statistical point-to-point uncorrelated as well as
correlated systematic uncertainties are taken into account in the comparison.
We detail this methodology and the resulting constraint on the model
parameters, such as the initial color-charge density dN^g/dy, the medium
transport coefficient , or the initial energy-loss parameter epsilon_0.
We find that high transverse momentum pi^0 suppression in Au+Au collisions has
sufficient precision to constrain these model dependent parameters at the +/1
20%-25% (one standard deviation) level. These constraints include only the
experimental uncertainties, and further studies are needed to compute the
corresponding theoretical uncertainties.Comment: 422 authors, 13 pages text, RevTeX-4, 9 figures, 2 tables. This
version is updated with changes made during the review process and is now the
same as what was published in Physical Review C. Plain text data tables for
the points plotted in figures for this and previous PHENIX publications are
publicly available at http://www.phenix.bnl.gov/papers.htm
Measurement of high-p_T Single Electrons from Heavy-Flavor Decays in p+p Collisions at sqrt(s) = 200 GeV
The momentum distribution of electrons from decays of heavy flavor (charm and
beauty) for midrapidity |y| < 0.35 in p+p collisions at sqrt(s) = 200 GeV has
been measured by the PHENIX experiment at the Relativistic Heavy Ion Collider
(RHIC) over the transverse momentum range 0.3 < p_T < 9 GeV/c. Two independent
methods have been used to determine the heavy flavor yields, and the results
are in good agreement with each other. A fixed-order-plus-next-to-leading-log
pQCD calculation agrees with the data within the theoretical and experimental
uncertainties, with the data/theory ratio of 1.72 +/- 0.02^stat +/- 0.19^sys
for 0.3 < p_T < 9 GeV/c. The total charm production cross section at this
energy has also been deduced to be sigma_(c c^bar) = 567 +/- 57^stat +/-
224^sys micro barns.Comment: 375 authors from 57 institutions, 6 pages, 3 figures. Submitted to
Physical Review Letters. Plain text data tables for the points plotted in
figures for this and previous PHENIX publications are (or will be) publicly
available at http://www.phenix.bnl.gov/papers.htm
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