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Investigating the antiproton cross section on nuclei at low energies (1 eV – 1 MeV) is of great interest for fundamental cosmology and nuclear physics as well. The process is of great relevance for the models which try to explain the matter/antimatter asymmetry in the universe assuming the existence of the so-called “island” where antinucleon-nucleon annihilations occur in the border region [1]. For the nuclear physics point of view, the annihilation process is considered a useful tool to evaluate the neutron/proton ratio probing the external region of the nucleus. Moreover, the cross section measured at LEAR in the 80s–90s showed an unexpected behaviour for energies below 1 MeV. The results showed a saturation with the atomic mass number against the A2/3 trend which is known for higher energies. The ASACUSA collaboration at CERN measured 5.3 MeV antiproton annihilation cross section on different nuclei whose results demonstrated to be consistent with the black-disk model with the Coulomb correction [2]. So far, experimental limits prevented the data acquisition for energies below 1 MeV. In 2012 the 100 keV region has been investigated for the first time [3]. We present here the results of the experiment.

The ASACUSA (Atomic Spectroscopy and Collisions Using Slow Antiprotons) collaboration is currently attempting to observe a laser-induced resonant transition of antiprotonic helium atoms at wavelength of 1154.9 nm. Motivations to observe this transition and a nanosecond near-infrared laser prepared for this work are presented.

The ASACUSA (Atomic Spectroscopy And Collisions Using Slow Antiprotons) collaboration of CERN is currently attempting to measure the antiproton-nucleus in-flight annihilation cross sections on thin target foils of C, Pd, and Pt at 130 keV of kinetic energy. The low-energy antiprotons were supplied by the Antiproton Decelerator (AD) and a radio-frequency quadrupole decelerator. For this measurement, a beam profile monitor based on secondary electron emission was developed. Data from this monitor was used to ensure that antiprotons were precisely tuned to the position of an 80-mm-diameter experimental target, by measuring the spatial profile of 200-ns-long beam pulses containing 105 − 106 antiprotons with an active area of 40 mm × 40 mm and a spatial resolution of 4 mm. By using this monitor, we succeeded in finely tuning antiproton beams on the target, and observed some annihilation events originating from the target.

Using an isolated Milky Way-mass galaxy simulation, we compare results from nine state-of-the-art gravito-hydrodynamics codes widely used in the numerical community. We utilize the infrastructure we have built for the AGORA High-resolution Galaxy Simulations Comparison Project. This includes the common disk initial conditions, common physics models (e.g., radiative cooling and UV background by the standardized package Grackle) and common analysis toolkit yt, all of which are publicly available. Subgrid physics models such as Jeans pressure floor, star formation, supernova feedback energy, and metal production are carefully constrained across code platforms. With numerical accuracy that resolves the disk scale height, we find that the codes overall agree well with one another in many dimensions including: gas and stellar surface densities, rotation curves, velocity dispersions, density and temperature distribution functions, disk vertical heights, stellar clumps, star formation rates, and Kennicutt-Schmidt relations. Quantities such as velocity dispersions are very robust (agreement within a few tens of percent at all radii) while measures like newly formed stellar clump mass functions show more significant variation (difference by up to a factor of ∼3). Systematic differences exist, for example, between mesh-based and particle-based codes in the low-density region, and between more diffusive and less diffusive schemes in the high-density tail of the density distribution. Yet intrinsic code differences are generally small compared to the variations in numerical implementations of the common subgrid physics such as supernova feedback. Our experiment reassures that, if adequately designed in accordance with our proposed common parameters, results of a modern high-resolution galaxy formation simulation are more sensitive to input physics than to intrinsic differences in numerical schemes.

Aim: To develop a sensitive and selective liquid-chromatographic method for the determination of histamine in microdialysis samples from guinea pig skin following allergenic provocation. Methods: The novel fluorescence derivatization method is based on an intramolecular excimer-forming reaction between 2 amino moieties of histamine and 2 molecules of 4-(1-pyrene)butanoyl chloride (PBC) yielding the corresponding dipyrene-labeled derivative. Results: The PBC derivative of histamine was separated within 20 min, and the detection limit (signal-to-noise ratio = 3) of histamine was 0.6 fmol/20 μl volume injected. The basal extracellular levels of histamine in guinea pig skin microdialysates were 20.6 ± 1.7 fmol/10 μl. Subcutaneous administration of histamine liberator compound 48/80 (3 mg/kg) increased the extracellular histamine levels in the skin dialysates by about 860%, whereas ovalbumin challenge (2 mg/kg i.v.) in the sensitized guinea pigs increased the extracellular histamine levels by about 3,030%. Conclusion: The novel technique for histamine determination in microdialysis samples from the guinea pig skin may be utilized in preclinical research of antihistaminergic drugs and evaluation of allergenic properties of various dermal preparations such as transdermal drug delivery systems. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Goals Of Work: The objective of this study was to determine how psychological characteristics, subjective symptoms, a family history of breast cancer, and age impact psychological distress in outpatients at the first hospital visit prior to breast cancer diagnosis.Materials and Methods: Participants were prediagnosed women with complaints of breast symptoms who either came to our hospital directly, or with a referral from another clinic. Patients were asked to complete questionnaires to determine the following: trait anxiety (State-Trait Anxiety Inventory), negative emotional suppression (Courtauld Emotional Control Scale), life stress events (Life Experiences Survey), and psychological distress (Profile of Mood States). We examined subjective symptoms (lumps, pain, abnormal nipple discharge, or deformed nipple) and family history of breast cancer based on answers to the interview sheet filled out by patients on their first visit. We analyzed a total of 154 patients who completed the questionnaires out of 237 eligible patients.Main Results: A significant model was obtained by multiple regression analysis (adjusted R (2) = 0.574, p < 0.01) in which the standard partial regression coefficients for trait anxiety, suppression of anxiety, negative life change events, positive life change events, and subjective symptoms were statistically significant (beta = 0.623, 0.133, 0.155, 0.108, and 0.124, respectively; p < 0.05).Conclusions: Psychological distress prior to diagnosis was higher in patients who had high trait anxiety, suppression of anxiety, many life stress events, and subjective symptoms. In particular, trait anxiety had a large impact on psychological distress, underscoring the need for and importance of adequate psychological care. [ABSTRACT FROM AUTHOR]

We performed a precision missing-mass spectroscopy experiment of the deeply bound pionic states in a 121Sn atom using the (d,3He) reaction near the π− emission threshold. The experiment serves as a pilot experiment for our new ‘pionic atom factory project’ at RIBF, which aims at precision spectroscopy of the energy spectrum of the pionic atom of isotopes and isotones. The result of the pilot experiment demonstrated the potentiality of BigRIPS and of the RIBF facilities for the project. The current status of the analysis is reported.

We have performed an inclusive spectroscopy of 122Sn(d, 3He) reaction near the pion emission threshold at an incident energy of Td = 250 MeV/nucleon. The first experiment aims as devloping the high precision spectroscopy of pionic atoms at the RI beam factory (RIBF) of RIKEN, which leads to a new project, pionic Atom Factory project (piAF) to measure pionic atoms for a wide range of elements. We report the analysis status of the pilot experiment.