Measurements of neutron total and capture cross sections of 139^{139}La and evaluation of resonance parameters

Neutron total and capture cross sections of Lanthanum(La)-139 were measured at the Accurate Ne-utron-Nucleus Reaction measurement Instrument (ANNRI) of the Materials and Life Science Experimental Facility (MLF) in the Japan Proton Accelerator Research Complex (J-PARC). The total cross section was largely different from that in evaluated libraries, such as JENDL-5, in the energy range from 80 to 900~eV. Resonance parameters for four resonances including one negative resonance were obtained using a resonance analysis code, REFIT. The resonance analysis revealed discrepancies in several resonance parameters with the evaluated libraries. Furthermore, the information about the scattering radius was also extracted from the results of the total cross section. The obtained scattering radius was larger than that recorded in the evaluated libraries.Comment: 12 pages, 16 figure

De Novo Design of a Nanopore for DNA Detection Incorporating a β-hairpin Peptide

The amino acid sequence of a protein encodes information on its three-dimensional structure and specific functionality. De novo protein design has emerged as a method to manipulate the primary structure for the development of artificial proteins and peptides with desired functionality. This paper describes the de novo design of a pore-forming peptide that has a β-hairpin structure and assembles to form a stable nanopore in a bilayer lipid membrane. This large synthetic nanopore is an entirely artificial device with practical applications. This peptide, named SV28, forms nanopore structures ranging from 1.6 to 6.2 nm in diameter assembled from 7 to 18 monomers. The nanopore formed with a diameter of 5 nm is able to detect long double-stranded DNA (dsDNA) with 1 kbp length, and measurement of current signals allowed us to investigate the translocation behavior of dsDNA at the single molecule level. Such de novo design of peptide sequences has the potential to create assembled structure in lipid membrane such as novel nanopores, which would also be applicable in molecular transporter between inside and outside of lipid membrane

Successful treatment of acyclovir‐resistant herpes simplex virus infection with amenamevir in a patient who received umbilical cord blood transplantation for T‐cell prolymphocytic leukemia

Abstract A 34‐year‐old woman received umbilical cord blood transplantation for refractory T‐cell prolymphocytic leukemia after salvage therapy with alemtuzumab. She developed right angular cheilitis on the 46th day after transplantation, which worsened after receiving systemic steroid therapy for extensive chronic graft versus host disease. The treatment dosage of acyclovir (ACV), ganciclovir, and vidarabine ointment was not effective due to ACV‐resistant mutations of the herpes simplex virus type 1 (HSV‐1) in the thymidine kinase domain. Foscarnet is expected to be effective against ACV‐resistant HSV‐1 infection. However, it could not be used because the patient developed renal dysfunction. Several viral thymidine kinase mutations related to ACV resistance were found in the patient's sample. Nevertheless, amenamevir, a helicase‐primase complex inhibitor, was effective in our patient who was significantly immunocompromised after allogeneic hematopoietic stem cell transplantation (allo‐HSCT). ACV‐resistant HSV infection after allo‐HSCT is an rare but important complication in the era of low‐dose long‐term ACV prophylaxis. To date, there is no established treatment against ACV‐resistant HSV infection. This case report showed that amenamevir could be a promising treatment option for ACV‐resistant HSV infection in patients with renal failure after allo‐HSCT

Present Status of Spectroscopy of the Hyperfine Structure and Repolarization of Muonic Helium Atoms at J-PARC

The mass mμ− of the negative muon is one of the parameters of the elementary particle Standard Model and it allows us to verify the CPT (charge–parity–time) symmetry theorem by comparing mμ− value with the mass mμ+ of the positive muon. However, the experimental determination precision of mμ− is 3.1ppm, which is an order of magnitude lower than the determination precision of mμ+ at 120ppb. The authors aim to determine mμ− and the magnetic moment μμ− with a precision of O(10ppb) through spectroscopy of the hyperfine structure (HFS) of muonic helium-4 atom (4Heμ−e−) under high magnetic fields. He4μ−e− is an exotic atom where one of the two electrons of the He4 atom is replaced by a negative muon. To achieve the goal, it is necessary to determine the HFS of He4μ−e− with a precision of O(1ppb). This paper describes the determination procedure of the HFS of He4μ−e− in weak magnetic fields reported recently, and the work towards achieving the goal of higher precision measurement

Offline analysis of the chemical composition and hygroscopicity of sub-micrometer aerosol at an Asian outflow receptor site and comparison with online measurements

Filter-based offline analysis of atmospheric aerosol hygroscopicity coupled to composition analysis provides information complementary to that obtained from online analysis. However, its application itself and comparison to online analysis have remained limited to date. In this study, daily submicrometer aerosol particles (PM0.95, 50 % cutoff diameter 0.95 µm) were collected onto quartz fiber filters on Okinawa Island, a receptor of East Asian outflow, in the autumn of 2015. The chemical composition of water-soluble matter (WSM) in PM0.95, PM0.95 itself, and their respective hygroscopicities were characterized through the offline use of an aerosol mass spectrometer and a hygroscopicity tandem differential mobility analyzer. Thereafter, results were compared with those obtained from online analyses. Sulfate dominated the WSM mass (59 %), followed by water-soluble organic matter (WSOM, 20 %) and ammonium (13 %). WSOM accounted for most (91 %) of the mass of extracted organic matter (EOM) and the atomic O-to-C ratios (O : C) of WSOM and EOM were high (mean ± standard deviation were 0.84 ± 0.08 and 0.78 ± 0.08, respectively), both of which indicate highly aged characteristics of the observed aerosol. The hygroscopic growth curves showed clear hysteresis for most samples. At 85 % relative humidity (RH), the calculated hygroscopicity parameter κ values of the WSM (κWSM), WSOM, EOM, andPM0.95 (κPM0.95 ) were 0.50 ± 0.03, 0.22 ± 0.12, 0.20 ± 0.11, and 0.47 ± 0.03, respectively. An analysis using the thermodynamic Extended Aerosol Inorganics Model (E-AIM) shows, on average, that inorganic salts and WSOM contributed 88 % and 12 %, respectively, of the κWSM (or κPM0.95 ). High similarities were found between offline and online analysis for chemical compositions that are related to particle hygroscopicity (the mass fractions and O : C of organics and the degree of neutralization) and also for aerosol hygroscopicity. As possible factors governing the variation in κWSM, the influences of WSOM abundance and the neutralization of inorganic salts were assessed. At high RH (70 %–90 %), the hygroscopicity of WSM and PM0.95 was affected considerably by the presence of organic components; at low RH (20 %–50 %), the degree of neutralization could be important.This study not only characterized aerosol hygroscopicity at the receptor site of East Asian outflow but also shows that offline hygroscopicity analysis is an appropriate method, at least for aerosols of the studied type. The results encourage further applications to other environments and to more in-depth hygroscopicity analysis, in particular for organic fractions