22 research outputs found
First application of mass measurement with the Rare-RI Ring reveals the solar r-process abundance trend at A=122 and A=123
The Rare-RI Ring (R3) is a recently commissioned cyclotron-like storage ring
mass spectrometer dedicated to mass measurements of exotic nuclei far from
stability at Radioactive Isotope Beam Factory (RIBF) in RIKEN. The first
application of mass measurement using the R3 mass spectrometer at RIBF is
reported. Rare isotopes produced at RIBF, Sn, In, Cd,
Ag, Pd, were injected in R3. Masses of In, Cd,
and Pd were measured whereby the mass uncertainty of Pd was
improved. This is the first reported measurement with a new storage ring mass
spectrometery technique realized at a heavy-ion cyclotron and employing
individual injection of the pre-identified rare nuclei. The latter is essential
for the future mass measurements of the rarest isotopes produced at RIBF. The
impact of the new Pd result on the solar -process abundances in a
neutron star merger event is investigated by performing reaction network
calculations of 20 trajectories with varying electron fraction . It is
found that the neutron capture cross section on Pd increases by a
factor of 2.2 and -delayed neutron emission probability,
, of Rh increases by 14\%. The neutron capture cross
section on Pd decreases by a factor of 2.6 leading to pileup of
material at , thus reproducing the trend of the solar -process
abundances. The trend of the two-neutron separation energies (S)
was investigated for the Pd isotopic chain. The new mass measurement with
improved uncertainty excludes large changes of the S value at
. Such large increase of the S values before was
proposed as an alternative to the quenching of the shell gap to
reproduce -process abundances in the mass region of
Epidemiology and Clinical Features of Pulmonary Nontuberculous Mycobacteriosis in Nagasaki, Japan
Background and Objectives: Recent reports indicate that the incidence of nontuberculous mycobacterial-lung disease (NTM-LD) is increasing. This study aimed to investigate the epidemiology and clinical features of NTM-LD patients in Nagasaki prefecture, Japan to identify the negative prognostic factors for NTM-LD in Japan. Methods: The medical records of patients newly diagnosed with NTM-LD in eleven hospitals in Nagasaki prefecture between January 2001 and February 2010 were reviewed. Data regarding the annual population of each region and the incidence of all forms of tuberculosis were collected to assess geographic variations in NTM-LD incidence, isolates, and radiological features. Results: A total 975 patients were diagnosed with NTM-LD. The incidence increased over the study period and reached 11.0 and 10.1 per 100,000 population in 2008 and 2009, respectively. M. intracellulare was the most common pathogen in the southern region, and M. avium most common in other regions. The most common radiographic pattern was the nodular-bronchiectatic pattern. Age >60 years, body mass index <18.5 kg/m2, underlying lung disease, and cavitary pattern were the negative prognostic factors at the 1-year follow-up. Conclusions: The incidence of NTM-LD has been increasing in Nagasaki prefecture. The isolates and radiographic features of patients vary markedly by region