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Optical model or coupled-channels calculation serves as an entrance to sophisticated calculation of nuclear data. It gives the optical quantities such as total, shape elastic scattering, absorption cross sections, direct inelastic scattering cross sections, angular distributions of elastic and inelastic scattering, and transmission coefficients for subsequent statistical model calculations. Traditionally, coupling of the elastic scattering channel to excited states of the target nucleus was ignored or treated with a simplified model such as rigid rotor or harmonic oscillator. It was a great contribution of Dr. Efrem Sh. Soukhovitsukii who has developed an excellent computation scheme which takes account of the low-lying collective nuclear structure in terms of the soft-rotator + vibrational model, and integrated it into the coupled-channels calculation. This methodology was realized as 2 computer codes, SHEMMAN and OPTMAN. In Japan, we had a fortuitous experience with him to employ this methodology in nuclear data evaluation, which started as a nuclear physics work to analyze neutron-scattering cross section of 12 C which were published as a series of 3 papers in Nuclear Physics A journal. After recognizing the usefulness of this methodology, it was applied to evaluation of nuclear data gradually and extensively, which resulted in obtaining awards of Atomic Energy Society of Japan (AESJ) by one of the authors (SK). This paper describes our collaborative works and recent findings on light-nuclei based on what he had developed. [ABSTRACT FROM AUTHOR]

Intensive neutron sources using deuteron accelerators have been proposed not only in science but also in engineering and medical fields. For the design study of such facilities, accurate and comprehensive nuclear database for deuteron-induced reactions are indispensable. Due to the limited experimental data, theoretical model calculations play key roles in the development of nuclear database. Under these circumstances, we have been developing a code system for deuteron-induced reactions, called the DEUteron-induced Reaction Analysis Code System (DEURACS). In this paper, we present some analysis results of experimental data using DEURACS in terms with (d, xn), (d, xp), and (d, xd) reactions that are important in deuteron transport simulation for the design study of the accelerator-based neutron sources. [ABSTRACT FROM AUTHOR]

Saxitoxin (STX), a neurotoxin isolated from Alaskan butter clam, Saxidomus giganteus, inhibits voltage-gated sodium channels by binding to the pore-forming p-loop region. Here we describe stereospecific syntheses of STX and its natural derivatives, (+)-decarbamoylsaxitoxin (dcSTX) and (+)-gonyautoxin3 (GTX3). [ABSTRACT FROM AUTHOR]

Several quantities that can be observed in surrogate ratio methods (SRM) are investigated for nuclei of uranium region to see if they can be used to infer the spin-and-parity distributions that are crucially important to the validity of SRM. The evaporation neutron spectra and cascading γ-ray spectra are calculated by the Hauser-Feshbach theory, while fission fragment mass distributions are calculated by the fluctuation-dissipation theorem. It was found that the energy spectrum of cascading γ rays and those of evaporated neutrons become softer as the spin of the decaying nuclei increases. The multiplicity of emitted γ rays increases drastically as the spin increases. Both these effects are brought about by the fact that transition from high-spin states to low-lying levels are hindered. The mass distribution of fission fragments also shows a clear spin dependence, namely, the mass-symmetric fission is enhanced when the spin of the decaying system is large. This can be interpreted as an enhancement of mass division controlled by the liquid-drop energy relative to the shell correction part. The present results indicate that there are possibilities to use these observables to infer populated spin distributions in the surrogate reactions. [ABSTRACT FROM AUTHOR]

The neutron capture cross sections of 129 I and 127 I were measured from the thermal to the keV energy regions with the NaI(Tl) spectrometer of the Accurate Neutron-Nucleus Reaction Measurement Instrument beamline in the Materials and Life Science Experimental Facility of the Japan Proton Accelerator Research Complex. The neutron capture yield was determined by means of the total energy detection principle with the pulse-height weighting technique. The present cross section results for 127 I were normalized using the saturated resonance method with a thick-enough 197 Au sample and provide good overall agreement with JENDL-5 from thermal to about 500 keV. A resonance analysis with the REFIT code was performed and the resonance parameters for both 129 I and 127 I below 100 eV are presented in this work. In the case of 129 I, four large resonances of 127 I were employed for the cross section normalization since it was included as an impurity. The present results for 129 I are the first experimental data to cover a wide neutron region from 10 meV to about 30 keV. In the neutron region between thermal and 20 eV, the present results display a different energy dependence than that in the JENDL-5 and JEFF-3.3 and much similar to that in ENDF/B-VIII.0. Notwithstanding, good agreement was found at the thermal region between the present measurement of 31.0 ± 1.4 b and both evaluated and most experimental data. [ABSTRACT FROM AUTHOR]

The neutron total and capture cross sections of 181Ta were measured at the Accurate Neutron-Nucleus Research Measurement Instrument of the Materials and Life Science Experimental Facility in the Japan Proton Accelerator Research Complex to improve the accuracy of the current resonance parameters. The total cross section was determined from the transmission measurement in the energy range from 0.2 to 150 eV. The capture cross section was derived from the capture yield using the pulse height weighting technique in the energy range from thermal to 150 eV. The thermal neutron capture cross section was measured as $$21.3 \pm 0.3(stat) \pm 0.6(sys)$$ 21.3 ± 0.3 (stat) ± 0.6 (sys) b. The obtained transmission and capture cross section were simultaneously fitted using the resonance analysis code REFIT, and the resonance parameters for resonances below 150 eV were evaluated. The present resonance parameters were compared to reported measurements. [ABSTRACT FROM AUTHOR]

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 deduced from transmission measurement using a Li-glass detector in the energy range from 0.5 to 1500 eV, and the capture cross section was measured by a NaI detector in the energy range from 0.5 to 74 eV. 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. [ABSTRACT FROM AUTHOR]

Review: 43 refs. [ABSTRACT FROM AUTHOR]

Double-differential cross-sections of the 9Be(p,xn) reaction are newly evaluated based on the Wakabayashi's function and neutronics analysis up to 12 MeV for a new nuclear data library, JENDL-5. We devoted our efforts especially to the re-optimization of the absolute cross-sections and the interpolation of the neutron energy spectra. Through the comparisons between the thick target yield measurements and Monte-Carlo simulations at different proton energies and neutron emission angles, we conclude that JENDL-5 gives the best evaluation in the world. [ABSTRACT FROM AUTHOR]

The measurements of Cs isotopic ratios by TIMS were performed for the sample analysis used to evaluation of the nuclear data of 135Cs. To obtain a high intensity and stable ion beam, the effects of additive agents on the ionization of Cs were examined. The effect of silicotungstic acid on the ionization of Cs was the largest among the additive agents discussed in this study, while this also showed the largest isobaric interference of polyatomic ions. After examining of the analytical conditions, such as the interference effect due to Ba, the sample analysis of two radioactive Cs samples were conducted. [ABSTRACT FROM AUTHOR]

Novel thienopyrimidine compounds 2 and 3 were discovered from high-throughput screening as Natriuretic Peptide Receptor A (NPR-A) agonists. Scaffold hopping of a thienopyrimidine ring to a quinazoline ring, introduction of the basic functional group and optimization of the substituent on the 6-position of the benzene ring of quinazoline led to improved agonistic activity. We discovered compound 48 , which showed potent agonistic activity for NPR-A with an EC 50 value of 0.073 μM, indicating 350-fold potency compared to the hit compound 3 . [ABSTRACT FROM AUTHOR]

A 27-year-old female was referred to our hospital with a chief complaint of removal of an impacted right mandibular third molar. Panoramic radiography showed two small circular radiolucencies on the right mandibular ramus. Computed tomography revealed that one of the radiolucencies was an accessory foramen located lateral to the mandibular ramus, and the other radiolucency was an accessory foramen located medial to the ramus; it was also connected to the mylohyoid groove. Continuity with the mandibular canal was confirmed for both accessory foramina. After explaining the risks of extraction, the patient decided against surgery and the impacted tooth was left in situ. Most patients have at least one or more accessory foramina in the mandible; however, accessory foramina of the lateral aspect of the mandibular ramus have not been reported. The high resolution of cone-beam computed tomography and three-dimensional reconstructed images enable improved detection of accessory foramina. Therefore, additional accessory foramina that are similar to those found in the present case could be found in the future using such imaging modalities. [ABSTRACT FROM AUTHOR]

We present a diastereoselective synthesis of disubstituted cyclopentane 8 having a nitrogen-containing quaternary carbon center, which is found in axinellamine A ( 5) and related compounds. During this work, we found that the 1,3-dipolar cycloaddition product 24 immediately underwent intramolecular redox reaction at the newly formed morpholin-2-one moiety, thus affording disubstituted cyclopentane containing a tertiary amine ( 9) stereoselectively in good yield. The amine 9 was successfully converted into guanidine 31, which corresponds to 8, through iminium cation-enamine isomerization. [ABSTRACT FROM AUTHOR]

The occurrence of angiosarcoma in the oral cavity is extremely rare, and optimal management of this tumor is undefined. These tumors are aggressive, with a high propensity for local recurrence. We present here a case of primary gingival angiosarcoma successfully treated by intra-arterial chemotherapy concurrent with radiation therapy. A 69-year-old female with a primary angiosarcoma in the right maxillary gingiva was admitted to our hospital. The diagnosis of angiosarcoma was established by immunohistochemistry. The patient refused surgical treatment, and so intra-arterial cisplatin and concurrent radiation were given. The gingival tumor disappeared after completion of the therapeutic regimen. However, the patient died 8 months after initial treatment because of multiple lung metastases. Locoregional control was achieved up to her death. To our knowledge, this is the first report of this treatment for angiosarcoma of the oral cavity. [ABSTRACT FROM AUTHOR]

To examine whether cancer cell dissemination results from incisional biopsy, we tried to detect squamous cell carcinoma (SCC) cells in peripheral blood before and after incisional biopsy by means of cytokeratin 19 (CK19) reverse-transcriptase polymerase chain reaction (RT-PCR). The study population consisted of 20 patients with oral SCC; 10 were given incisional biopsies followed by radical excision (the incisional biopsy group), and the remaining 10 were treated by excisional biopsy alone (the excisional biopsy group). Ten non-oral cancer patients with benign oral lesions served as controls. Five-ml blood aspirates collected before and after incision were used for CK19 RT-PCR. Two (20.0%) of 10 patients from the incisional biopsy group were positive for CK19 transcripts in their peripheral blood drained 15 min after incision. In contrast, CK19 transcript was not detected either in the excisional biopsy group or in controls. Surgical invasiveness for oral cancer, including incisional biopsy, causes dissemination of cancer cells into circulation, resulting in increased risk of metastasis. [ABSTRACT FROM AUTHOR]

A neutron filtering system has been introduced in the Accurate Neutron–Nucleus Reaction Measurement Instrument (ANNRI) beamline in the Materials and Life Science (MLF) facility of the Japan Proton Accelerator Research Complex (J-PARC) in order to produce quasi-monoenergetic neutron beams. The filtered neutron spectrum by the filter assemblies was analyzed by means of capture and transmission measurements and also by Monte Carlo simulations using PHITS. The characteristics of the filtered neutron beam are discussed alongside its viability in future applications for neutron cross-section measurements in the fast neutron region. [ABSTRACT FROM AUTHOR]