The global polarization of Λ hyperons along the total orbital angular momentum of a relativistic heavy-ion collision is presented based on the high statistics data samples collected in Au+Au ...collisions at sNN=2.4 GeV and Ag+Ag at 2.55 GeV with the High-Acceptance Di-Electron Spectrometer (HADES) at GSI, Darmstadt. This is the first measurement below the strangeness production threshold in nucleon-nucleon collisions. Results are reported as a function of the collision centrality as well as a function of the hyperon's transverse momentum (pT) and rapidity (yCM) for the range of centrality 0–40%. We observe a strong centrality dependence of the polarization with an increasing signal towards peripheral collisions. For mid-central (20 – 40%) collisions the polarization magnitudes are 〈PΛ〉(%)=6.8±1.3(stat.)±2.1(syst.) for Au+Au and 〈PΛ〉(%)=6.2±0.4(stat.)±0.6(syst.) for Ag+Ag, which are the largest values observed so far. This observation thus provides a continuation of the increasing trend previously observed by STAR and contrasts expectations from recent theoretical calculations predicting a maximum in the region of collision energies about 3 GeV. The observed polarization is of a similar magnitude as predicted by 3D-fluid-dynamics and the UrQMD plus thermal vorticity model and significantly above results from the AMPT model.
Cherenkov Electromagnetic Calorimeter (ECAL) was recently installed to complement the dilepton spectrometer HADES currently operating at SIS18 accelerator (GSI, Darmstadt, Germany). ECAL will be used ...to measure the meson and photon production in heavy ion collisions at the beam energy range of 1–10 A GeV. The calorimeter will also improve the electron–hadron separation. ECAL covers forward polar angles 16°<θ<45° and almost full azimuthal angle of the HADES acceptance. ECAL consists of 978 modules divided into 6 sectors. Each module consists of a lead glass Cherenkov block with light readout by a photomultiplier. The test bench to measure the light output of the ECAL modules from the cosmic muons and “in-situ” measurements at HADES are discussed. The relative energy resolution for cosmic muons was estimated during the tests.
Since the incidence of transplant renal artery stenosis (TRAS) in renal allografts varies from 1% to 23%, we sought to examine its incidence, to analyze treatment options, and to ascertain its ...outcomes. Retrospective analysis of 793 kidney allograft recipients transplanted between 1996 and 2004 revealed an incidence of 0.9% (n = 7). Time from kidney transplantation to the first symptoms varied from 1 week to 3 years (median, 4 months). Three patients experiences refractory hypertension and six patients developed allograft dysfunction. Screening color Doppler ultrasonography showed hemodynamic changes in six patients with the definitive diagnosis confirmed by angiography in all patients. One patient with an anastomotic stenosis was treated with a surgical operation and six patients, percutaneous transluminal angioplasty (PTA), with stenting in three cases. Both surgical as well as PTA treatment were successful in all but one patient, who underwent PTA alone, developed chronic renal insufficiency necessitating hemodialysis and finally lost his allograft. In the other patients all symptoms resolved after treatment and the patients are doing well with functioning allografts. Although TRAS was an uncommon complication, if recognized promptly it could be treated by surgery or PTA with a high success rate.
A feasibility study has been performed in order to investigate the performance of the HADES detector to measure the electromagnetic decays of the hyperon resonances
Σ
(
1385
)
0
,
Λ
(
1405
)
and
...Λ
(
1520
)
as well as the production of double strange baryon systems
Ξ
-
and
Λ
Λ
in p + p reactions at a beam kinetic energy of
4.5
GeV
. The existing HADES detector will be upgraded by a new Forward Detector, which extends the detector acceptance into a range of polar angles that plays a crucial role for these investigations. The analysis of each channel is preceded by a consideration of the production cross-sections. Afterwards the expected signal count rates using a target consisting of either liquid hydrogen or polyethylene are summarized.
Abstract The production of $$\Sigma ^{0}$$ Σ 0 hyperons in proton proton collisions at a beam kinetic energy of 3.5 GeV impinging on a liquid hydrogen target was investigated using data collected ...with the HADES setup. The total production cross section is found to be $${\sigma (pK^{+}\Sigma ^{0}) = 17.7 \pm 1.7 (stat) \pm 1.6 (syst)}$$ σ ( p K + Σ 0 ) = 17.7 ± 1.7 ( s t a t ) ± 1.6 ( s y s t ) µb. Differential cross section distributions of the exclusive channel $${pp \rightarrow pK^{+}\Sigma ^{0}}$$ p p → p K + Σ 0 were analyzed in the center-of-mass, Gottfried–Jackson and helicity reference frames for the first time at the excess energy of 556 MeV. The data support the interplay between pion and kaon exchange mechanisms and clearly demonstrate the contribution of interfering nucleon resonances decaying to $$\textrm{K}^{+}\Sigma ^{0}$$ K + Σ 0 . The Bonn–Gatchina partial wave analysis was employed to analyse the data. Due to the limited statistics, it was not possible to obtain an unambiguous determination of the relative contribution of intermediate nucleon resonances to the final state. However nucleon resonances with masses around 1.710 $${\textrm{GeV}/\textrm{c}^{2}}$$ GeV / c 2 ( $${\textrm{N}^{*}(1710)}$$ N ∗ ( 1710 ) ) and 1.900 $${\textrm{GeV}/\textrm{c}^{2}}$$ GeV / c 2 ( $${\textrm{N}^{*}(1900)}$$ N ∗ ( 1900 ) or $${\Delta ^{*}(1900)}$$ Δ ∗ ( 1900 ) ) are preferred by the fit.
The production of
Σ
0
hyperons in proton proton collisions at a beam kinetic energy of 3.5 GeV impinging on a liquid hydrogen target was investigated using data collected with the HADES setup. The ...total production cross section is found to be
σ
(
p
K
+
Σ
0
)
=
17.7
±
1.7
(
s
t
a
t
)
±
1.6
(
s
y
s
t
)
µb. Differential cross section distributions of the exclusive channel
p
p
→
p
K
+
Σ
0
were analyzed in the center-of-mass, Gottfried–Jackson and helicity reference frames for the first time at the excess energy of 556 MeV. The data support the interplay between pion and kaon exchange mechanisms and clearly demonstrate the contribution of interfering nucleon resonances decaying to
K
+
Σ
0
. The Bonn–Gatchina partial wave analysis was employed to analyse the data. Due to the limited statistics, it was not possible to obtain an unambiguous determination of the relative contribution of intermediate nucleon resonances to the final state. However nucleon resonances with masses around 1.710
GeV
/
c
2
(
N
∗
(
1710
)
) and 1.900
GeV
/
c
2
(
N
∗
(
1900
)
or
Δ
∗
(
1900
)
) are preferred by the fit.
The aim of the study was to assess the molecular background of the alloimmune response by the detection of low-abundance mRNA of cytokines in 34 core needle biopsies from kidney allografts with ...histopathological findings of acute rejection (AR). Recipients were immunosuppressed with a calcineurin inhibitor (CNI), cyclosporine or tacrolimus, and prednisone and azathioprine or mycophenolate mofetil (MMF). Tubular and glomerular expression of IL-2, IL-6, IL-10, IFN-γ, TGF-β1, and PDGF-B mRNA were assessed using semiquantitative evaluations of RT-PCR in situ on paraffin tissue sections. This procedure resulted in light microscopy visualization of granular precipitates at the sites of the corresponding mRNA chains. The tubular expression of mRNA for IL-6 and TGF-β1 was significantly lower in biopsies with AR (n = 34) obtained from patients treated with MMF (n = 12) than in biopsies obtained from patients treated with azathioprine (n = 22) (
P < .02). Responsiveness to corticosteroids tended to be more frequent among the MMF group (11 of 12 recipients vs 15 of 22 recipients,
P = ns). Moreover, 8 of 12 recipients in the MMF-treated group displayed serum creatinine levels equal or less than 167 mmol/L 1 year after biopsy compared to 7 of 22 recipients in the azathioprine-treated group. There was no significant difference between the groups that had or had not received corticosteroids or between those treated with each type of CNI. These results suggest stronger inhibition of humoral responses and down-regulation of fibrosis by MMF among recipients with AR.
The evolution of Czech standards requires higher efficiency of nutrient removal from municipal wastewaters. At the beginning of the last decade of 20th century, a new activated sludge configuration ...called R-AN-D-N process has been described, successfully tested and now largely used at several wastewater treatment plants (WWTP) in the Czech republic. The main feature of the R-AN-D-N process is the introduction of a regeneration zone in sludge recycle, which enables to increase sludge age in the system without any substantial increase in WWTP volume. Performances of three Czech large WWTP with R-AN-D-N configuration have been monitored and compared within a period of one and a half years. The results confirmed excellent nutrient removal efficiency for wastewaters with different proportion between sewage and industrial effluents. Two of three monitored WWTP received wastewaters from breweries (Budweiser and Pilsner Urquell). The settleability of activated sludge from all three WWTP was correct, with SVI values usually ranging from 50 to 150 ml/g. Monitoring of sludge composition indicated proliferation of several filamentous bacteria, particularly types 0581, 0092 and M. parvicella. No severe bulking events were observed. Finally, the operational costs expressed in CZK (Czech crown: 1 CZK = see symbol in text0.0322) per cubic metre of treated sewage or per capita amounts respectively from 2.24 to 6.52, and from 285 to 342.
PDF
