87 research outputs found
The role of resonances in reaction and its important implications
The reaction is a very good isospin 3/2 filter for
studying decaying to . With an effective Lagrangian
approach, contributions from a previous ignored sub--threshold
resonance are fully included in addition to those
already considered in previous calculations. It is found that the
resonance gives an overwhelmingly dominant
contribution for energies very close to threshold, with a very important
contribution from the t-channel exchange. This solves the problem that
all previous calculations seriously underestimate the near-threshold cross
section by order(s) of magnitude. Many important implications of the results
are discussed.Comment: 11 pages, 3 figure
Role of the N*(1440) resonance in the pp->pnpi+ reaction
New measurement by CELSIUS-WASA Collaboration on the pp->pn pi+ reaction
reveals clear evidence for the presence of the Roper resonance N*(1440) which
has been ignored in previous theoretical calculations. In this article, based
on an effective Lagrangian approach and available knowledge on the Roper
resonance, we investigate the role of the Roper resonance for the pp->pn pi+
reaction. It is found that the contribution from the Roper resonance N*(1440)
becomes significant for kinetic energy above 1.1 GeV, consistent with the new
experimental observation. The t-channel sigma-meson exchange is dominant for
the production of the Roper resonance.Comment: 13 pages, 4 figure
The role of in and reactions
The near threshold meson production in proton-proton and
collisions is studied with the assumption that the production mechanism is due
to the sub--threshold resonance. The , and
-meson exchanges for proton-proton collisions are considered. It is
shown that the contribution to the reaction from the t-channel
meson exchange is dominant. With a significant
coupling ( = 0.13), both and
data are very well reproduced. The significant coupling of
the resonance to is compatible with previous indications
of a large component in the quark wave function of the
resonance and may be the real origin of the significant enhancement of the
production over the naive OZI-rule predictions.Comment: 15 pages, 6 figure
High Resolution Continuous Flow Analysis System developed at the Ice Core Research Center National Institute of Polar Research
第6回極域科学シンポジウム[OM] 極域気水圏11月16日(月) 統計数理研究所 セミナー室2(D304
Oxidative stress induction of DJ-1 protein in reactive astrocytes scavenges free radicals and reduces cell injury
Astrocytes, one of the predominant types of glial cells, function as both supportive and metabolic cells for the brain. Under cerebral ischemia/reperfusion-induced oxidative conditions, astrocytes accumulate and activate in the ischemic region. DJ-1 has recently been shown to be a sensor of oxidative stress in living cells. However, the function of astrocytic DJ-1 is still unknown. In the present study, to clarify the effect of astrocytic DJ-1 protein under massive oxidative insult, we used a focal ischemic rat model that had been subjected to middle cerebral artery occlusion (MCAO) and reperfusion. We then investigated changes in the distribution of DJ-1 in astrocytes, DJ-1 release from cultured astrocytes, and the effects of recombinant DJ-1 protein on hydrogen peroxide (H2O2)-induced death in normal and DJ-1-knockdown SH-SY5Y cells and on in vitro scavenging of hydroxyl radicals (•OH) by electron spin resonance spectrometry. At 24 h after 2-h MCAO and reperfusion, an infarct lesion was markedly observed using magnetic resonance imaging and 2,3,5-triphenyltetrazolium chloride staining. In addition, reactive astrocytes enhanced DJ-1 expression in the penumbral zone of the ischemic core and that DJ-1 protein was extracellularly released from astrocytes by H2O2 in in vitro primary cultures. Although DJ-1-knockdown SH-SY5Y cells were markedly vulnerable to oxidative stress, treatment with glutathione S-transferase-tagged recombinant human DJ-1 protein (GST-DJ-1) significantly inhibited H2O2-induced cell death. In addition, GST-DJ-1 protein directly scavenged •OH. These results suggest that oxidative stress induces the release of astrocytic DJ-1 protein, which may contribute to astrocyte-mediated neuroprotection
New structure around 3250 MeV in the baryonic B decay and the molecular hadron
In this work, we first propose the isovector molecular
state to explain the enhancement structure around 3250 MeV () in
the invariant mass spectrum newly observed by the
BaBar Collaboration. Under this molecular state configuration, both the
analysis of the mass spectrum and the study of its dominant decay channel can
well depict its resonance parameters measured by BaBar. Our investigation also
shows that the isovector molecular state can decay into
, which is consistent with the experimental
observation. These studies provide the direct support to the isovector
molecular state assignment to .Comment: 5 pages, 1 table, 4 figures. Accepted by Eur. Phys. J.
The Gender–Age–Physiology system as a prognostic model in patients with idiopathic pulmonary fibrosis treated with nintedanib: a longitudinal cohort study
Introduction: The Gender-Age-Physiology (GAP) system is a tool for predicting prognosis in patients with idiopathic pulmonary fibrosis (IPF). Yet, to date, the GAP system has not been evaluated in patients with IPF who received nintedanib. Material and methods: This single-center retrospective study included 89 patients with IPF who received Nintedanib for at least 3 months. All-cause mortality was set as the end point. Clinical parameters, including the GAP stage, were statistically analyzed for risk factors leading to mortality using the Cox proportional hazard model.Results: The median follow-up was 16.4 months (range 3.7–37.4 months), during which 23 patients died. Univariate analysis revealed that the GAP stage (hazard ratio [HR] 3.00, 95% confidence interval [CI] 1.52–5.92, p = 0.0014) and PaO2 (HR 0.95, 95% CI 0.92–0.98, p = 0.0063) were significant prognostic factors. Multivariate analysis revealed that the GAP stage was a significant prognostic factor (HR 2.26, 95% CI 1.07–4.78, p = 0.031). Log-rank analysis revealed that there were no significant differences in “Gender” (p = 0.47) and “Age” (p = 0.18) factors. However, there were significant differences in “Physiology” factors (% of forced vital capacity, p = 0.018; % of diffusing capacity of lung carbon monoxide, p < 0.001). The cumulative incidences of mortality at 1 and 2 years were as follows: GAP I: 5.1% and 6.8%; GAP II: 9.5% and 29.3%; and GAP III: 18.9% and 84.2%.Conclusions: The GAP system is useful as a prognostic tool in patients with IPF who have been treated with nintedanib
Feasibility of cord blood transplantation in chemosensitive adult T-cell leukemia/lymphoma: a retrospective analysis of the Nagasaki Transplantation Network
It has been reported that cord blood transplantation (CBT) for patients with aggressive adult T-cell leukemia/ lymphoma (ATL) results in poorer outcomes than transplantation using other stem cell sources. To identify a subset of ATL in which CBT is feasible, we retrospectively analyzed 27 patients treated with CBT at three institutions in Nagasaki Prefecture, Japan. The estimated overall survival (OS) rate at 3 years was 27.4 %. Of 16 patients who received CBT during remission (complete, CR, or partial, PR), the OS rate at 3 years was 50 %, while during refractory periods (non-CR or non-PR), the OS rate was 9.1 %. Reduced intensity conditioning (RIC) was given to 18 patients, and myeloablative conditioning (MAC) was used in nine, with 3-year OS of 50.0 and 0 %, respectively. Of the 19 deaths, nine were due to progressive disease, eight (five MAC and three RIC) to infection, and two to multiple organ failure. These results suggest that CBT provides similar results with those in other transplantation procedures for selected ATL patients, such as those in CR or PR. Further studies are needed to evaluate the use of CBT in aggressive ATL
Risk factors for acute exacerbation following bronchoalveolar lavage in patients with suspected idiopathic pulmonary fibrosis: A retrospective cohort study
Introduction: Bronchoalveolar lavage (BAL) is useful for diagnosing diffuse lung disease and excluding other conditions. However, acute exacerbations (AEs) are recognized as important complications of BAL in patients with idiopathic pulmonary fibrosis (IPF). This study aimed to identify risk factors for BAL-induced AEs in patients with IPF.Material and methods: We retrospectively analyzed the data of 155 patients with suspected IPF who had undergone BAL between January 2013 and December 2018. BAL-related AE was defined as the development of AE within 30 days after the procedure. We compared clinical features and parameters between patients with AE (AE group) and without AE (non-AE group). We also reviewed the relevant reported literature.Results: Among the 155 patients, 5 (3.2%) developed AE within 30 days after BAL. The average duration from BAL to AE onset was 7.8 days (2–16 days). Results from the univariate analysis revealed PaO2 < 75 mm Hg (p = 0.036), neutrophil content in BAL ≥ 7% (p = 0.0061), %DLCO < 50% (p = 0.019), Gender-Age-Physiology (GAP) stage III (p = 0.034), and BAL recovery rates < 30% (p < 0.001) as significant risk factors for post-BAL AE. All five patients who developed AE recovered and were discharged.Conclusions: Disease severity, high neutrophil levels in BAL, and poor BAL recovery rates may be risk factors for BAL-induced AE
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