210 research outputs found
How Critical is Early Initiation of Extracorporeal Membrane Oxygenation for Rescue Support in Severe Refractory Cardiogenic Shock?
The nonmesonic weak decay of the hypertriton
The nonmesonic decay of the hypertriton is calculated based on a hypertriton
wavefunction and 3N scattering states, which are rigorous solutions of 3-body
Faddeev equations using realistic NN and hyperon-nucleon interactions. The
pion-exchange together with heavier meson exchanges for the transition is considered. The total nonmesonic decay rate is found to be 0.5%
of the free decay rate. Integrated as well as differential decay
rates are given. The p- and n- induced decays are discussed thoroughly and it
is shown that the corresponding total rates cannot be measured individually.Comment: 27 pages, 20 figures, revtex, submitted to Phys. Rev.
Pion-Lambda-Sigma Coupling Extracted from Hyperonic Atoms
The latest measurements of the atomic level width in Sigma-hyperonic Pb atom
offer the most accurate datum in the region of low-energy Sigma-hyperon
physics. Atomic widths are due to the conversion of Sigma-nucleon into
Lambda-nucleon. In high angular momentum states this conversion is dominated by
the one-pion exchange. A joint analysis of the data of the scattering of
negative-Sigma on proton converting into a Lambda and a neutron and of the
atomic widths allows to extract a pseudovector pion-hyperon-Sigma coupling
constant of 0.048 with a statistical error of +-0.005 and a systematic one of
+-0.004. This corresponds to a pseudoscalar coupling constant of 13.3 with a
statistical uncertainty of 1.4 and a systematic one of 1.1.Comment: 12 pages, 1 figure, Use of Revtex.st
Surgery versus stereotactic radiotherapy for treatment of pulmonary metastases. A systematic review of literature
It is not clear as to which is the best treatment among surgery and stereotactic radiotherapy (SBRT) for lung oligometastases. A systematic review of literature with a priori selection criteria was conducted on articles on the treatment of pulmonary metastases with surgery or SBRT. Only original articles with a population of patients of more than 50 were selected. After final selection, 61 articles on surgical treatment and 18 on SBRT were included. No difference was encountered in short-term survival between pulmonary metastasectomy and SBRT. In the long-term surgery seems to guarantee better survival rates. Mortality and morbidity after treatment are 0-4.7% and 0-23% for surgery, and 0-2% and 4-31% for SBRT. Surgical metastasectomy remains the treatment of choice for pulmonary oligometastases. Patients with metastatic cancer with a limited number of deposits may benefit from surgical removal or irradiation of tumor nodules in addiction to chemotherapy. Surgical resection has been demonstrated to improve survival and, in some cases, can be curative. Stereotactic radiotherapy is emerging as a less invasive alternative to surgery, but settings and implications of the two treatments are profoundly different. The two techniques show similar results in the short-term, with lower complications rates for radiotherapy, while in the long-term surgery seems to guarantee higher survival rates
Inclusive and exclusive photoproduction on the deuteron: - and -threshold phenomena
Inclusive and exclusive photoproduction on the deuteron are
investigated theoretically. Modern hyperon-nucleon forces and a recently
updated kaon photoproduction operator for the process are
used. Sizable effects of the hyperon-nucleon final state interaction are found
near the and thresholds in the inclusive reaction.
Angular distributions for the exclusive process show clear final state
interaction effects in certain kinematic regions. Precise data especially for
the inclusive process around the threshold would help to clarify
the strength and property of the interaction.Comment: 14 pages, 10 figure
Quantification of recirculation as an adjuvant to transthoracic echocardiography for optimization of dual-lumen extracorporeal life support
Proper cannula positioning in single site veno-venous extracorporeal life support (vv-ELS) is cumbersome and necessitates image guidance to obtain a safe and stable position within the heart and the caval veins. Importantly, image-guided cannula positioning alone is not sufficient, as possible recirculation cannot be quantified. We present an ultrasound dilution technique allowing quantification of recirculation for optimizing vv-ELS. We suggest quantification of recirculation in addition to image guidance to provide optimal vv-ELS
Hyperon-hyperon interactions and properties of neutron matter
We present results from Brueckner-Hartree-Fock calculatons for beta stable
neutron star matter with nucleonic and hyperonic degress degrees of freedom,
employing the most recent parametrizations of the baryon-baryon interaction of
the Nijmegen group. It is found that the only strange baryons emergin in beta
stable matter up to total barionic densities of 1.2 fm^-3 are and
. The corresponding equations of state are then used to compute
properties of neutron stars such as masses and radii.Comment: 27 pages, LateX, includes 8 PostScript figures, (submitted to PRC
Associated strangeness production at threshold
The associated strangeness dissociation at threshold has been studied at the
COSY-11 facility measuring the hyperon - and the K+K- meson pair production.
Measurements of the near threshold Lambda and Sigma0 production via the pp ->
pK+ Lambda / Sigma0 reaction at COSY-11 have shown that the Lambda / Sigma0
cross section ratio exceeds the value at high excess energies (Q >= 300 MeV) by
an order of magnitude. For a better understanding additional data have been
taken between 13 MeV and 60 MeV excess energy.
The near threshold production of the charged kaon-antikaon pair is related to
the discussion about the nature of the scalar states in the 1 GeV/c^2 mass
range, i.e. the f0(980) and a0(980). The interpretation as a K anti-K molecule
is strongly dependent on the K anti-K interaction which can be studied via the
production channel. A first total cross section value on the reaction pp ->
ppK+K- at an excess energy of 17 MeV i.e. below the phi production threshold
was measured.Comment: 3 pages, 2 figures, Presented at Conference on Quarks and Nuclear
Physics (QNP 2002), Julich, Germany, 9-14 Jun 200
Effectiveness and cost-effectiveness of rubber band ligation versus sutured mucopexy versus haemorrhoidectomy in patients with recurrent haemorrhoidal disease (Napoleon trial):Study protocol for a multicentre randomized controlled trial
Background: Currently, there is no consensus regarding the best treatment option in recurrent haemorrhoidal disease (HD), due to a lack of solid evidence. The Napoleon trial aims to provide high-level evidence on the comparative effectiveness and cost-effectiveness of repeat rubber band ligation (RBL) versus sutured mucopexy versus haemorrhoidectomy in patients with recurrent HD. Methods: This is a multicentre randomized controlled trial. Patients with recurrent HD grade II and III, >= 18 years of age and who had at least two RBL treatments in the last three years are eligible for inclusion. Exclusion criteria include previous rectal or anal surgery, rectal radiation, pre-existing sphincter injury or otherwise pathologies of the colon and rectum, pregnancy, presence of hypercoagulability disorders, and medically unfit for surgery (ASA > III). Between June 2020 and May 2022, 558 patients will be randomized to receive either: (1) RBL, (2) sutured mucopexy, or (3) haemorrhoidectomy. The primary outcomes are recurrence after 52 weeks and patient-reported symptoms measured by the PROM-HISS. Secondary outcomes are impact on daily life, treatment satisfaction, early and late complication rates, health-related quality of life, costs and cost-effectiveness, and budget impact. Cost-effectiveness will be expressed in societal costs per Quality Adjusted Life Year (QALY) (based on EQ-5D-5L), and healthcare costs per recurrence avoided. Discussion: The best treatment option for recurrent HD remains unknown. The comparison of three generally accepted treatment strategies in a randomized controlled trial will provide high-level evidence on the most (cost) effective treatment
Strangeness Production in Proton-Proton Collisions Close to Threshold
Exclusive data on the reactions pp -> ppK+K- and pp -> pK+ Lambda/Sigma0 have
been taken at the cooler synchrotron COSY close to threshold. At equal excess
energies, an enhancement of the Lambda/Sigma0 ratio by one order of magnitude
has been observed compared to data at higher excess energies. New results
obtained at the COSY-11 facility explore the transition region between this
low-energy Sigma0 suppression and excess energies of 60 MeV. A first total
cross section for elementary antikaon production below the phi threshold has
been determined, two orders of magnitude smaller compared to kaon production at
the same excess energy.Comment: 4 pages, 2 figures, Talk given by P. Moskal at 16th International
Conference on Particles and Nuclei (PANIC 02), Osaka, Japan, 30 Sep - 4 Oct
200
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